Terahertz waves (THz,T-ray) lie between far-infrared and microwave inelectromagnetic spectrum with frequency from 0.1 to 10 THz. Many chemical agentexplosives show characteristic spectral features in the terahertz. Compared withconventional methods of detecting a variety of threats, such as weapons andchemical agent, THz radiation is low frequency and non-ionizing, and does notgive rise to safety concerns. The present paper summarizes the latest progress inthe application of terahertz time domain spectroscopy (THz-TDS) to chemical agentexplosives. A kind of device on laser radar detecting and real time spectrummeasuring was designed which measures the laser spectrum on the bases of Fourieroptics and optical signal processing. Wedge interferometer was used as the beamsplitter to wipe off the background light and detect the laser and measure thespectrum. The result indicates that 10 ns laser radar pulse can be detected andmany factors affecting experiments are also introduced. The combination of laserradar spectrum detecting, THz-TDS, modern pattern recognition and signalprocessing technology is the developing trend of remote detection for chemicalagent explosives.

According to Stark broadening theory, Stark broadening spectral lineprofile is asymmetric in essence considering plasma ions impact. The electricmicrofield distribution function is very important for the spectral line profile.The Stark broadening spectral line profile is described with different electricmicrofield distribution functions. The results show that the Stark broadeningspectral line profile is similar with the Holtsmark distribution and nearest-neighbor field distribution, and it is diversification with Mayer model. With thedecrease in the electrons impact broadening parameter, the influence of differentelectric microfield distribution functions is diminished. With the decrease inthe plasma ions impact parameter, the influence of different electric microfielddistribution functions is trailing off. The results also show that the action ofelectric microfield distribution functions is similar when the plasma ions impactparameter is very small. It is illustrated that the intense impact of plasma ionshas great influence on the spectral line profile. The results may have importantreference for the plasma diagnosis.Spectral diagnosis2006000950)和河北大学科研基金项目(2006Q10)资助

The molecular geometries of four 2,4-dimethyl-7-amino-1,8-naphthyridinederivatives were optimized with B3LYP/6-31G(d) method. The energies of theirfrontier molecular orbitals and the molecular structures were investigatedtheoretically. The theoretical electronic spectra were calculated with TD-DFT ingas phase, PCM-TD-B3LYP/6-31+G(d) and semiempirical ZINDO in CH2Cl2 solution. Theinfluences of solvent model and calculation methods on the electronic absorptionspectra were also probed. The calculated results show that delocalized π bondsexist in the four 1,8-naphthyridine derivatives, and their energy gaps (ΔE)between HOMO and LUMO are relatively small. The variation in their ΔE valuesgives a consistent trend with that of their electronic absorption with λmax.Theoretical spectra achieved prove that their absorptions are red-shifted whenthe delocalization of π electrons is enhanced or the capability to donateelectron by a substituted group is increased. The maximum absorption peaks of thefour derivatives originate from π(HOMO)→π*(LUMO) transition. The spectracalculated at the PCM-B3LYP/6-31+G(d) level have little difference fromexperimental results: the differences in wavelength are 2.6, 10.3, 5.3 and 6.9nm, whereas those in energies are 0.03, 0.09, 0.04 and 0.08 eV, respectively. Theobtained results suggest that electronic spectra calculated by TD-DFT on thebases of geometries optimized with B3LYP/6-31(d) are in agreement withexperimental ones, and can account for the different spectroscopic properties ofthe four 1,8-naphthyridine derivatives.spectra; TD-DFT

Nanocrystalline ZnO films were deposited on quartz substrates by radio-frequency magnetron sputtering (RFMS) method. The authors discussed the effectcaused by the change in the ratio of oxygen to argon and quartz substratestemperature on the qualities of thin films and blue photoluminescence spectrum ofZnO films. Relationship between XRD intensity and FWHM of nanocrystalline ZnOfilms at different ratio of O2/Ar in processing was given. Photoluminescencespectrum (PL), absorption spectra (ABS), photoluminescence excitation spectrum(PLE) and X-ray diffraction pattern (XRD) of nanocrystalline ZnO film withexcitation wavelength 300 nm were measured at room temperature. XRD patternindicates that nanocrystalline ZnO film has a hexagonal wurtzite structure and ispolycrystalline. Blue visible emission bands (430-460 nm) were observed, and itscentral wavelength is 445 nm. The relationship between PL area of integration andPL intensity of maximum of nanocrystalline ZnO films at different ratio of O2/Arin processing was given. The luminescence emission peak located at 450 nmcorresponds to the transition from the shallow level of oxygen vacancy to valenceband or the interstitial.(2007RFXXG038)资助

The electroluminescence effect can be observed by the micro N-typewide-gap CBN semiconductor crystal under the condition of static eletric field.The micro N-type CBN crystal was fixed on the focus of the parabolic reflector ofgrating monochromator, and the maximum value of transmission ratio and the idealsignal-noise ratio can be obtained. Under the condition of static ectric-fieldintensity (4.7×106 V?cm-1), the blue-violet light-emitting spectrum of the CBNcrystal was measured in the range from 350 to 450 nm. The construction of the CBNenergy band, which was calculated with the First-principles method, the nonlinearrelationship between current density and the ectric-field intensity that wasmeasured and the phenomenon of electrical break-down were considered together toenable us to discuss the luminescence mechanism. Finally, the authors came upwith the luminescence mechanism concerning electron migration from Γ energyvalley to X energy valley. The large number of excited electrons we talked aboutwere generated by polarization and breakdown of defect dipole before avalanchebreakdown occurred.valey; Generalized gradient approximation(GGA)

With the development of organic light-emitting diodes, interests in themechanisms of charge carrier photo generation, separation, transport andrecombination continue to grow. Phosphorescent organic light-emitting diodes havegained considerable interest in the last 10 years because of high luminanceefficiency. In the present paper, the authors investigated the optical andelectrical characteristics of the devices based on Ir(ppy)3 and Ir(piq)3 dopedPVK matrix emission layer at room temperature. The PL spectra show that theenergy transfer from PVK to Ir(piq)3 is harder than that of PVK to Ir(ppy)3. TheLuminescence characteristics of devices with different doping ratio show that itis not the energy transfer from matrix, but the recombination of injectedcarriers on phosphorescent molecules that is the main origin of EL emissions.From the viewpoint of energy level, the characteristics of carrier-trap andtransport in Ir(piq)3 are better than in Ir(ppy)3 due to the high HOMO and lowLUMO in Ir(piq)3.基金项目(20090009110027, 20070004024), 博士点新教师基金项目(20070004031), 北京市科技新星计划项目(2007A024), 北京市自然科学基金项目(1102028)和中埃科技合作联委会中方项目(5-Ⅲ-19)资助

High-resolution X-ray imaging systems require materials with goodscintillation performances, especially X-ray absorption performance. Comparedwith powder phosphors display devices, those with transparent crystallinephosphors are very interesting due to their higher contrast and resolution forhaving no optical scattering, superior thermal conductivity as well as highdegree of uniformity and better adhesion. Europium-doped gadolinium oxide is apromising candidate due to its high density (7.62 g?cm-3), good light yield(18.5×103 photons/MeV), and the red emission of Eu3+ ion. The sol-gel method isone of the most important techniques for deposition of functional films, becauseit possesses a number of advantages over conventional film formation techniques,such as low processing temperature, easy coating of large surfaces, andhomogenous multicomponent oxide films. In X-ray imaging application, thethickness of the film is the most important factor for commercial use, which canincrease X-ray absorption of the film and then strengthen its luminescence yield.In the present work, transparent Gd2O3∶Eu3+ thick film was successfully preparedusing sol-gel method and spin-coating technique by choosing Ln2O3 (Ln=Gd, Eu) asraw materials, 2-methoxyethanol as solvent, PVP as adhesive and PEG200 as surfacemodifier. The film was homogeneous and crack free. The thickness of the filmcould achieve 1.5 μm after 2 times of coating, and its transmittance wasapproximately 80% in visible region. It was shown that PVP played an importantrole in film preparation, which could suppress stress and increase viscidity ofthe sol. In addition, the excitation, emission and decay time of the Gd2O3∶Eu3+scintillator film were studied. Their performances were quite good, which impliedthat the film would have promising applications in high-spatial-resolution X-rayimaging and flat panel display devices.properties(07dz22302)资助

Mn-doped ZnS nanopatricles synthesized by solvothermal method weresuccessfully coated with SiO2 shells of various thicknesses by hydrolysisreaction of tetraethyl orthosilicate (TEOS). The samples were characterized by X-ray diffraction(XRD), transmission electron microscopy images (TEM), X-rayphotoelectron spectroscopy (XPS) and the room temperature photoluminescence (PL)spectra. When the ZnS∶Mn nanoparticles were coated with SiO2 shells, an obviousincrease in particle size and a clear shell of SiO2 can be observed. The XPSmeasurement also gave the evidence for the core/shell structure of ZnS∶Mn/SiO2nanoparticles. Because the surface modification effect and the decrease inluminescent centers effect are concurrent in the SiO2 shells, the Mn emissionintensity first increased and then decreased with the thickening of the SiO2shell. The intensity, which attained its maxium at 5 shell thickness, was as 7times as that for the bare ZnS∶Mn nanoparticles.(2006BS04034)和2008年教育部新世纪优秀人才支持计划项目(NCET-08-0511)资助

A new europium (Ⅲ) complex, EuL3phen, ［HL=4,4,4-trifluoro-1-(4’-m-terphenyl)-1, 3-butanedione, phen=1,10-phenanthroline］ was synthesized. Itsstructure was characterized by elemental analysis, IR and FAB-MS. The complexexhibits strongly red emission due to the 5D0—7FJ(J=0-4) transitions of Eu3+ions under irradiation of UV or 395 nm emission light of InGaN chip. Thestrongest emission peak is located at 613 nm. The luminescence quantum yieldis13%. The lifetime of the complex is 470 μs. The decay curve can be fit with asingle exponential. The thermogravimetric analyses curve for the complex showsthat the complex is stable up to 220 ℃, which meets the requirement offabrication of LED device. A red luminescent LED was successfully fabricated bycoating complex EuL3phen onto 395 nm emitting InGaN chip. The mass ratio ofcomplex to the silicone is related to the chromaticity coordinates and efficiencyof fabricated LED. When the mass ratio of complex to the silicone is 1∶25, thechromaticity coordinates of the fabricated LED with the europium complex arex=0.64 and y=0.35 and the efficiency achieves 0.89 lm?W-1. The results indicatethat the complex may act as a potential red component in the fabrication of whiteLEDs.Luminescence

Series of Tm3+/Yb3+ co-doped GdF3 powders were synthesized through aneasy and mild hydrothermal method. The phase and purity of powders werecharacterized by powder X-ray diffraction (XRD) (Rigaku RU-200b). Themorphologies of the samples were characterized by field emission scanningelectron microscopy (FE-SEM) (Hitachi S-4800). The ultraviolet (UV) up-conversion(UC)emission spectra were recorded by a fluorescence spectrophotometer (HitachiF-4500) with a 980 nm semiconductor continuous wave laser diode as the excitationsource. And the luminescent dynamics was measured by excitation with 980 nm usingan optical parameter oscillator (OPO) laser pumped by a pulsed Nd∶YAG laser witha pulse duration of 10 ns, repetition frequency of 10 Hz, and the signal wasrecorded by using a monochromator and an oscillograph. Under 980 nm excitation,Gd3+, acting as a kind of host ion in the studied system, and its UV UC emissionswere observed and studied. The luminescent dynamics of the characteristicemission of Gd3+ (311.6 nm, 6P7/2→8S7/2) was explored and studied. Theluminescent dynamics analysis results indicated that, on UV UC emissions of Gd3+,Yb3+ ions served as primary sensitizer ions successively transferring energy toTm3+ to populate the 3P2 level. Then, Tm3+ ions served as secondary sensitizerions transferring energy to populate the multiple 6IJ states of Gd3+ 3P2→3H6(Tm3+): 8S7/2→6IJ (Gd3+). Further, 6DJ levels were populated through otherenergy transfer processes between Gd3+ and Yb3+ or Tm3+. Finally, UV UC emissionsfrom the excited 6D9/2, 6IJ, 6P5/2, and 6P7/2 states to the ground state 8S7/2were observed. Meanwhile, Tm3+ acted as activator in its own UC emissions, andthe article did not put emphasis on those except the 3P2 and 1I6 levels to theground state 3H6 transitions. Especially, the dependences of UV UC emissions ofGd3+ on the Yb3+ concentrations, the Tm3+ concentrations, the annealingtemperatures, and the excitation power densities of the 980 nm semiconductorcontinuous wave laser diode were studied, too.Luminescent dynamics(2009GQW0010)和江西省教育厅科技计划项目(GJJ10203)资助

An improved conical bubble sonoluminescence U-tube was built. Usingthis setup, the spectra and light pulses of conical bubble luminescence inglycerin were detected. Results show that the spectra are continuum, which arewell fitted by blackbody radiation. The cavitational temperature ranging from 2600 to 3 050 K was calculated from the fitted spectra. The reasons for theexistence of blackbody radiation in conical bubble luminescence were discussedboth from special and temporal sides. The value of radius of cavitational bubbleis about 1.7 cm theoretically, which is greater than that of the bubbleacoustically excited. The width of light pulses of cavitational bubble reached40-60 ms,and this provided enough time for the blackbody radiation. In addition,the light pulses at different wavelength were measured, and results show that thewidth of light pulses increased with the raise of wavelength of spectra, whichproved the mechanism of blackbody radiation. Finally, based on the spectra andlight pulses, the intensity of luminescence was calculated to be about 0.18 J.Intensity

Double-layer organic light-emitting devices (OLEDs) based on a blendsystem of novel small molecule fluorene material 6,6′-(9H-fluoren-9,9-diyl)bis(2,3-bis(9,9-dihexyl-9H-fluoren-2-yl) quinoxaline) (BFLBBFLYQ) and holetransporting material N,N′-biphenyl-N,N′-bis-(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD) were fabricated. The structure of the double-layer device wasITO/BFLBBFLYQ∶TPD/tris(8-hydroxyquinolinato)aluminum(Alq)/Mg∶Ag. Thephotoluminescence (PL) spectra of BFLBBFLYQ and TPD were located at 447 and 414nm, respectively. The spectral characteristics of the blend system and thedouble-layer device were investigated, which indicated that a new long wavelengthemission peaking at 530 nm was appeared both in PL spectra andelectroluminescence (EL) spectra. The exciplex between BFLBBFLYQ and TPD may playthe role in long wavelength emission in the blend device and the spin-coatedfilm. Based on the absorption spectra of a red fluorescent dye 4-(dicyanomethylene)-2-tert-butyl-6(1,1,7,7-tetramethyljulolidyl-9-enyl)-4H-pyran(DCJTB) as probe and the PL spectra of the blend system showing good overlap,energy transfer from the blend system to DCJTB could be expected. Therefore,DCJTB could be selected as a molecular dopant to investigate the influence on ELspectra and the recombination of the devices. It was found that the excitonsrecombine at the interior Alq layer near to the BFLBBFLYQ∶TPD layer.Energy transfer; Recombination(60721001), (863计划)项目(2007AA03Z424), 教育部新世纪优秀人才计划项目(NCET-06-0812)和电子科技大学中青年学术带头人计划项目(060206)资助

In the present paper, the functional groups of PES/micro-nano cellulosecomposite membrane materials were characterized by Fourier transform infraredspectroscopy (FTIR). Also, changes in crystallinity in composite membranematerials were analyzed using X-ray diffraction (XRD). The effects of micro-nanocellulose content on hydrophilic property of composite membrane material werestudied by measuring hydrophilic angle. The images of support layer structure ofpure PES membrane material and composite membrane material were showed withscanning electron microscope (SEM). These results indicated that in the infraredspectrogram, the composite membrane material had characteristic peaks of both PESand micro-nano cellulose without appearance of other new characteristics peaks.It revealed that there were no new functional groups in the composite membranematerial, and the level of molecular compatibility was achieved, which was basedon the existence of inter-molecular hydrogen bond association between PES andmicro-nano cellulose. Due to the existence of micro-nano cellulose, thecrystallinity of composite membrane material was increased from 37.7% to 47.9%.The more the increase in micro-nano cellulose mass fraction, the better the vande waal force and hydrogen bond force between composite membrane material andwater were enhanced. The hydrophilic angle of composite membrane material wasdecreased from 55.8°to 45.8°and the surface energy was raised from 113.7 to123.5 mN?m-2. Consequently, the hydrophilic property of composite membranematerial was improved. The number of pores in the support layer of compositemembrane material was lager than that of pure PES membrane. Apparently, poreswere more uniformly distributed.高等教育学科创新引智计划项目(B08005)资助

Near-infrared reflectance spectroscopy (NIRS) was used as a rapid andnondestructive method to determine the protein content and gossypol content incotton kernel powder samples, using 49 upland cotton (Gossypium hirsutum L.)germplasms and 188 recombinant inbred lines (RILs). The cottonseed samplesharvested from the upland cotton germplasms and RILs grown in different cottongrowing regions in different years were analyzed chemically for protein andgossypol contents, as well as scanned in the reflectance mode of a scanningmonochromator. Using ISI software for scanning and data analysis, protein andgossypol calibration equations were obtained with a standard normal variate +detrending scatter correction and a 2, 4, 4, 1 math treatment and modifiedpartial least square (MPLS) as the regression method. The protein contentcalibration results revealed that the multiple correlation coefficients (RSQ) andstatistic 1-variance ratio (1-VR) for the determination of protein content incottonseed kernels were 0.933 and 0.929, respectively, and its standard error ofcalibration (SEC) and standard error of cross validation (SECV) were 0.623 and0.638, respectively. As the calibration equations were judged by the calibrationRSQ (or 1-VR) and SEC (or SECV), the results indicated that NIRS is comparable tochemical methods in both accuracy and prediction and is reliable in thedetermination of protein content in cottonseed kernels. However, the RSQ, SEC, 1-VR and SECV for gossypol content determination of NIRS were 0.836, 0.811, 0.074and 0.079, respectively. Although it was weaker than that of protein content, theNIRS method is still good enough for the determination and prediction of thegossypol content in cottonseed kernels. Therefore, NIRS models were successfullydeveloped for protein content and gossypol content analysis of cotton kernelpowder sample in the present study and they could be introduced into the cottongermplasm evaluation and breeding program for the cottonseed quality improvement.Gossypol content; Protein content)科研专项经费项目(nyhyzx07-052)资助

Fourier transform spectroscopy (FTIR) and two-dimensional correlationspectroscopy were used to analyze different compatibility forms ofsargentgloryvine stem, radix paeoniae rubra and cortex moutan in order to studythe FTIR spectra of different proportion formulas. The results indicate thatdifferent proportion formulas have distinct change regularity in FTIR spectra,second derivative spectra and synchronous 2D. Key components of sargentgloryvinestem’s characteristic absorption band are 1 610, 1 518 and 1 446 cm-1 which arecharacteristic absorption band of aromatic material, and in the original formula,that shows stronger peak than others, suggesting that original formula can makethe best of composition of drug action. In the different proportion formulas, 1614 cm-1 is nearer to 1 610 cm-1, which is sargentgloryvine stem’scharacteristic absorption band, than to 1 706 cm-1, illustrating thatsargentgloryvine stem is more influential formula than others. According toidentification and ascription of characteristic absorption band, it was initiallyrevealed that different proportion of drug dosage can affect pharmacodynamicaction of integral formula.

The present study introduced the generalized morphological filter intothe denoising of visible and near infrared spectra for the first time, andprovided a new method for denoising the reflectance spectra by combiningmathematical morphology methods with the wavelet packet transformation. Theauthors used vegetable spectra from USGS spectral library as the referencespectra, and obtained the noised spectra by adding noises with different signal-to-noise ratios to the referenced spectra. The results were evaluated by signal-to-noise ratio (SNR), root mean squared error (RMSE), normalized correlationcoefficient (NCC) and smoothness ratio (SR) of the denoised spectra. The authors’ results showed that both the thresholding on wavelet packet decomposition bestbases method and the generalized morphological filter method could maintain thespectral shape and the spectral smoothness after denoising. The generalizedmorphological filter method can remove larger amplitude random noise whereas thecontinuous small amplitude random noise could not be removed well. Hence, thedenoised spectra were not smooth. Nevertheless, the denoised spectra using thethresholding on the best base groups of wavelet packet decomposition method weresmooth, but the larger amplitude noise could not be removed completely. Theauthors’ method by combining the two methods has the merits of the two methodsbut removing their defects. The results showed that both large and smallamplitude noise could be removed completely, meanwhile the normalized correlationcoefficient (NCC) and smoothness ratio (SR) were improved, which indicated thatthe authors’ method is superior to other methods in denoising visible and nearinfrared spectra.morphological filter; Thresholding on wavelet packet decomposition best bases与中国科学院创新项目(Kzcx2-yw-107)联合资助

Near infrared (NIR) spectroscopy was investigated to predict trashcontent and classify types of ginned cotton by using a fiber-optic in diffusereflectance mode. Different spectra preprocessing methods were compared, andpartial least-squares (PLS) regression was established to predict the trashcontent of ginned cotton. Discriminant analysis (DA) was used to classify varioustypes of lint and content level of trash. The correlation coefficient r was 0.906for optimal PLS model using three factors based on first-order derivativespectra, and RMSEC and RMSEP was 0.440 and 0.823 respectively. To classify ginnedcotton with and without plant trash, the accuracy rate reached 95.4% using 15principal components (PCs) via DA, whereas the prediction accuracy rate was only80.9% for the classification of sample types due to containing foreign fiber, andthe classification result for the content level of trash in lint was not good forthe samples without any preprocessing. The result indicated that the NIR spectraof sample can be used to predict trash content in ginned cotton, which is oftendisturbed by type, content and distribution of foreign matters, and the accuracyof some prediction model is unsatisfactory. In order to improve the predictionaccuracy, some methods would be applied in future research, such as pretreatmentaccording to acquisition request of solid sample, or using transmission mode.Classification1)资助

In the present paper, after middle pressure chromatograph separationusing both positive phase and reversed-phase conditions, the organic additives inethylene-propylene rubber were identified by infrared spectrometer. At the sametime, by using solid phase extraction column to maintain the main component-fueloil in organic additves to avoid its interfering with minor compounds, otherorganic additves were separated and analysed by GC/Ms. In addition, the remainingactive compound such as benzoyl peroxide was identified by CC/Ms, throughanalyzing acetone extract directly. Using the above mentioned techniques, softenagents (fuel oil, plant oil and phthalte), curing agent (benzoylperoxide),vulcanizing accelerators (2-mercaptobenzothiazole, ethyl thiuram and butylthiuram), and antiagers (2,6-Di-tert-butyl-4-methyl phenol and styrenated phenol)in ethylene-propylene rubber were identified. Although the technique wasestablished in ethylene-propylene rubber system, it can be used in other rubbersystem.

The infrared radiation experiments on bolt and rock in the process ofloading were carried out. It was found that the infrared radiation temperaturesrose wholly and uniformly before stress peak with increase in loading. The boltedrock presented local dissimilation in the thermal image after stress peak. Themulti-layer round infrared radiation isothermal lines were formed around bolt.The temperature was gradually reduced from inside to outside. There were twokinds of infrared omens for bolted rock fracturing, i.e., the infrared thermalimage anomaly and curve of infrared radiation temperature and time anomaly, whichreflected the spatial and temporal features of infrared omens respectively. Thecurve of infrared radiation temperature and time anomaly was temperature drop.The infrared thermal image omen was classified as high-temperature strip and low-temperature strip.(2002CB412701)资助

In the present work, the combination of attenuated total reflectance-Fourier transform infrared spectrometry (ATR-FTIR) and pattern recognition,including principal components analysis (PCA) and hierarchical cluster analysis(HCA), is used as a fast and convenient analytical tool to classify oil samples.Twenty five samples including crude oils and fuel oils with different totalcontents of n-alkanes were analyzed. It was found that multiplicative scattercorrection (MSC) and continuous wavelet transform (CWT) as a pretreatment methodcould improve the classification results of pattern recognition. Theclassification results were proved to be in agreement with the origin of the oilsamples. The oils with high content of n-alkanes and those with low content wereclassified clearly by this developed method, but it still had some constraint todifferentiating oils with little difference. The present work provides a feasiblemethod for quick classification of oils, which can be used for the initialidentification of spill oils and afford useful information for the furtheridentification of the oils.infrared spectrometry (ATR-FTIR); Principal components analysis (PCA);Hierarchical cluster analysis (HCA)验室课题项目(200816)资助

A practical gas sensing system utilizing absorption spectrum scanningtechniques was developed. Using the narrow-band transmission of a fiber tunablefilter (TOF) and wavelength modulation technique, the so-called cross-sensingeffects of the traditional spectrum absorption based gas sensor were reducedeffectively and thus the target gas was detected sensitively and selectively. Inorder to reduce the effects of nonlinearity of TOF on the measurement results andimprove the system stability in operation, the reflection spectrum of a referenceFBG was monitored and employed to control the modulation region and center of TOFwavelength precisely. Moreover, a kind of weak signal detecting circuits wasdeveloped to detect the weak response signal of the system with high sensitivity.The properties of the proposed system were demonstrated experimentally bydetection of acetylene. Approximate linear relationships between the systemresponses and the input acetylene concentrations were demonstrated byexperiments. The minimum detectable acetylene of 5×10-6, with signal-noise ratioof 3, was also achieved by experiments.(FBGs); Tunable fiber filter助项目

CuO-CeO2 series catalysts are the effective catalysts for the selectiveCO oxidation in hydrogen-rich gas. The adsorption species on the CuO-CeO2catalysts doped with alkali and alkaline earth metal oxides were investigatedwith in situ diffuse reflectance FTIR spectroscopy (in-situ DRIFTS) technique.The results showed that a bane at 2 106 cm-1, due to the carbonyl species,appeared on the CuO-CeO2 catalysts. In the reaction atmosphere, the intensity ofthis band increased first and then decreased with increasing the temperatures. Itwas noted that the main active adsorption sites of the CuO-CeO2 catalysts wereCu+ species. At lower temperatures, the carbonyl species were desorbed from thesurface of CuO-CeO2 catalysts in the reversible form, while they were desorbedmainly in the irreversible form at the higher temperatures. A sharp peak at 3 660cm-1, attributed to the geminal Ce(OH)2 group, was also apparent on the surfaceof reduced CuO-CeO2 catalyst. The peaks at 1 568, 2 838 and 2 948 cm-1 wereattributed to formate species and the peaks centered at 1 257 and 1 633 cm-1 wereassigned to carbonate species. CO could react with the active hydroxyl speciesand generate formate species. At higher temperatures, the C—H bond of formatespecies could break and form carbonate species. These two species would decreasethe performance of CuO-CeO2 catalysts at higher temperatures. The stronger IRpeaks attributed to CO2 and formate species were observed, moreover there wasstill a weak IR peak assigned to carbonyl species for Cu1Li1Ce9Oδ catalyst whenthe temperature was above 180 ℃. It was shown that as the electron donor, thedoping of Li2O on CuO-CeO2 catalyst could contribute to the irreversibledesorption of CO at lower temperatures and inhibit the adsorption of H2 on thecatalytic surface, and benefit the formation of formate species as well. Althoughthe amounts of CO adsorption on Cu1Mg1Ce9Oδ and Cu1Ba1Ce9Oδ catalysts were muchmore than other catalysts at lower temperatures, they were mainly desorbed in thereversible form, which had no contribution to the selective CO oxidation.situ DRIFTS; Gas adsorption

The present study explored the efficiency of quantitative analysis forthe contents of total nitrogen (TN), total phosphorus (TP) and total potassium(TK) during chicken manure composting with chrysanthemum residue in a plant fieldusing a Thermo Nicolet Antaris near-infrared reflectance spectral apparatusequipped with InGaAs detectors (Thermo Nicolet Corporation, Chicago, USA). Thesamples used in this study were collected from different positions duringcomposting and were scanned in polyethylene bags at 2 cm-1 interval from 10 000to 4 000 cm-1 with 32 co-added scans. Regression models were developed usingspectral data and reference data by partial least square (PLS). In order toenhance chemical information and reduce data systemic noise, different datapreprocessing methods such as smoothing, 1st and 2nd derivative, standard normalvariety (SNV) and multiplicative scatter correction (MSC) were tested. Theoptimum preprocessing method was selected with the lowest root mean square errorof cross-validation (RMSECV). Outliers were removed on the basis of being labeledas compositional outliers by the criteria that the predicted-actual differencefor the sample was three standard deviations from the mean difference. Accordingto the concentration gradient of each parameter, all samples were divided into acalibration set (3/4 samples) and a validation set (1/4 samples). Leave-one-outcross validation was performed to avoid over-fitting on the calibration sets.Based on the values of determination coefficient (Ｒ2) and relative predictiondeviation (RPD) in validation sets, the prediction results were evaluated asexcellent for TP and TK, and approximate for TN. Hereinto, Ｒ2 and RPD valueswere greater than 0.82 and 2.0 for TN, and greater than 0.90 and 3.0 for TP andTK, respectively.Plant-field composting

The present research was focused on determination of the pH valueonline by visible and near-infrared spectroscopy. In the part of data gathering,fresh pork longissimus dorsi was moving at the constant velocity of 0.25 m?s-1on the conveyor belt, and the visible and near-infrared diffuse reflectancespectrum (350-1 000 nm) was captured. In the part of data processing, band of510-980 nm of the spectra was chosen to calibrate reflex distance, then to set uponline detection model of pH value in fresh pork by partial least squaresregression (PLSR). Kennard-stone algorithm was applied to divide the samples tothe calibration set and validation set. The performances of several PLSR modelsemploying various preprocessing methods including multiple scatter correction,derivative and both of them combined were compared. Further, the best performancemodel was optimized by interval PLSR to decrease the modeling variables ofwavelength. The results indicated that the PLSR model based on preprocessing ofmultiple scatter correction (MSC) combined with first derivative gave the bestperformance with 0.905 of the correlation coefficient for validation set and0.051 of the root of mean square errors for validation set. For the best PLSRmodel performance, the correlation coefficient of validation set increased to0.926 and the root of mean square errors for validation set to 0.045 in theoptimization interval PLSR model. However, only half of variables were used. Theresearch demonstrates that using visible and near-infrared spectroscopy todetermine fresh pork pH online is feasible.On-line determination; Fresh pork; pH(Y307441)资助

The aim of the present study was to develop a near-infrared reflectance(NIR) spectroscopy rapid method for evaluation of beef quality. Partial leastsquares (PLS) prediction model for the physic-chemical characteristics such asmoisture, fat, protein, pH, color and WBSF in beef was established with goodveracity. One hundred fourteen samples from five different parts of beef carcass(tenderloin, ribeye, topside, shin, striploin) were collected from meat packerafter 48 h aging. Spectra were obtained by scanning sample from 950 to 1 650 nmand pretreated the model by MSC, SNV and first derivative. Predictive correlationcoefficients of physic-chemical parameters in beef were 0.947 2(moisture), 0.9245(fat), 0.934 6(protein), 0.620 2(pH), 0.820 3(L), 0.864 6(a*), 0.753 0(b*) and0.475 9(WBSF) respectively. Root mean square errors of calibration (RMSEC) were0.313 3(moisture), 0.221 0(fat), 1.243 2(protein), 0.744 6(pH), 1.778 3(L*),1.394 2(a*), 1.763 9(b*) and 1.0743(WBSF). They were externally validated withadditional 30 beef samples. Statistics showed that there was no significantdifference between predicted value and those obtained with conventionallaboratory methods. The results showed that NIRS is a rapid, effective techniquefor evaluating beef quality. The predictions for chemical characteristics gavehigher accuracy than prediction for physical characteristics.(2004DA1251840802)资助

The Raman scattering coefficients of the fundamental ν1(992 cm-1) ofC6H6 and the fundamental ν１(656 cm-1) of CS2 changed dramatically with relativeconcentration of the binary solution of CS2 and C6H6. The Raman spectra of thebinary solution with different relative concentrations were measured. The resultsshow that both the ν1 fundamentals intensities changed dramatically with therelative concentration of the solution and the fundamental ν1 of C6H6 has littleeffect on the Fermi resonance ν１＋ν６～ν８. On the contrary, the change inthe ν１ fundamental intensity of the CS2 changed which has more effect not onlyon the Fermi resonance ν１～２ν２ but also on the ν２ fundamental. In thisreport, the experimental results were analyzed based on the J. F. Bertran theoryand group theory.

Confocal Raman microscopy system was used to investigate the etiologyof colorectal cancer at the molecular level. A total of two hundred and thirtyfour micro-Raman spectra were measured from thirty nine patients for surgicallyresected colorectal cancer specimens and adjacent normal tissues in the region900-2 100 cm-1. Two bands at 1 064 and 1 134 cm-1 which are attributed to theall-trans bond stretching vibrations of the C—C lipid skeleton decreased incolorectal cancer tissue samples. The ratio of the Raman band intensity at 1 299cm-1assigned to in-phase CH2 twisting vibrations of lipids to that at 1 264 cm-1from CH in-plane deformation was different for colorectal cancerous and normaltissues. The mean values of the (I1 299/I1 264) were 3.17 for normal tissues and1.33 for cancer tissues using the software function of “Compare Means”.Further, the scatter plots were used for grouping the ratio of Raman intensity at1 299 to 1 264 cm-1 according to tissue pathologic types by graph of theSPSS16.00 software. The decision lines (I1 299/I1 264=1.96) separates betweencancer and normal tissue with a coincidence rate of 94% (188/200) according tothe histological results by graph. The results show that the differences betweencancer and normal tissue spectra appear to arise from a decrease in the degree ofthe longitudinal order and an increase in the degree of unsaturation of lipid,which causes the fluidity of lipid to increases when normal cells are transformedinto cancerous cells.Cancer

In the present paper, the best experimental conditions for producinghydrates in the NaCl-H2O and MgCl2-H2O systems were found through the cryogenicRaman spectroscopy. This experimental condition is rapidly cooling to -180 ℃ andslowly warming to observe hydrate formation process (that is manifested as adarkening of the vision in the microscope), and finally, rapidly cooling down to-180 ℃. Moreover, a qualitative or semiquantitative analytical method for NaCl-MgCl2-H2O system was established. This method is that 3 537 cm-1 may instruct theexistence of NaCl hydrates, 3 514 cm-1 may instruct the existence of MgCl2hydrates, and comparison of the intensity of 3 537 and 3 514 cm-1 peaks can beused to estimate the ratio of NaCl and MgCl2 in the system. All these are thefoundations for quantifying the components of natural fluid inclusions. Theauthor supports Samson’s idea through observing the phenomenon of experiments inthe controversy of the meta-stable eutectics formation model, that is ice formson initial cooling, leaving a residual, interstitial, hypersaline liquid. Onwarming, the salt hydrates crystallize from this liquid.systems; Low temperature; Raman spectroscopy技部(973计划)项目(2002CB412605)资助

As the general method of defect characterization is destructive, duringthe current research on the effect of defect on device, nondestructive defectcharacterization is important especially. The defects of 4H-SiC homoepitaxiallayer had been observed and studied, based on the principle ofcathodoluminescence(CL). The results show that the intrinsic stacking faults(SFs), threading edge dislocations(TEDs), threading screw dislocations(TSDs) andbasal plane dislocations(BPDs) can be observed by cathodoluminescence. The shapeare rightangle triangle, dot and stick, repectively. So this method is availablefor nondestructive defect characterization. The correlation between 4H-SiCsubstrate defects and epilayer defects will be established if we characterize thedefects of 4H-SiC wafers with and without an epilayer. In addition, if wecharacterize the defects of device before and after operation, the correlationbetween SiC defects of the devices before and after operation will beestablished, too.characterization； Dislocations and stacking faults防基金项目(9140A08050508)资助

Taking ponceau 4R and amaranth as an example, concentration predictionand kind identification of synthetic food colors by fluorescence spectroscopy andradial basis function neural networks are introduced. By using SP-2558multifunctional spectral measuring system, the fluorescence spectra were measuredfor solution of ponceau 4R and amaranth excited respectively by the light withthe wavelength of 300 and 400 nm. For each sample solution of ponceau 4R, 15emission wavelength values were selected. The fluorescence intensitycorresponding to the selected wavelength was used as the network characteristicparameters, and a radial basis function neural network for concentrationprediction was trained and constructed. It was employed to predict ponceau 4Rsolution concentration of the three kinds of samples, and the relative errors ofprediction were 1.42%, 1.44% and 3.93% respectively. In addition, for solution ofponceau 4R and amaranth, the fluorescence intensity corresponding to thefluorescence wavelength was used as the network characteristic parameters, and aradial basis function neural network for kind identification was trained andconstructed. It was employed to identify the kind of food colors, and theaccuracy is 100%. These results show that the method is convenient, fast, andhighly accurate, and can be used for the detection of synthetic food color infood safety supervision and management.neural networks; Concentration prediction; Kind identification; Food safety(JH08-18)和研究生创新项目(CX08B-088Z)资助

An ASD Field Spec Pro Full Range spectrometer was used to acquire thespectral reflectance of healthy and diseased leaves infected by riceAphelenchoides besseyi Christie, which were cut from rice individuals in thepaddy field. Firstly, foliar pigment content was investigated. As compared withhealthy leaves, the total chlorophyll and carotene contents (mg?g-1) of diseasedleaves decreased 18% and 22%, respectively. The diseased foliar content ratio oftotal chlorophyll to carotene was nearly 82% of the healthy ones. Secondly, theresponse characteristics of hyperspectral reflectance of diseased leaves wereanalyzed. The spectral reflectance in the blue (450-520 nm), green (520-590 nm)and red (630-690 nm) regions were 2.5, 2 and 3.3 times the healthy onesrespectively due to the decrease in foliar pigment content, whereas in the nearinfrared (NIR, 770-890 nm) region was 71.7 of the healthy ones because of leaftwist, and 73.7% for shortwave infrared (SWIR, 1 500-2 400 nm) region, owing towater loss. Moreover, the hyperspectral feature parameters derived from the rawspectra and the first derivative spectra were analyzed. The red edge position(REP) and blue edge position (BEP) shifted about 8 and 10 nm toward the shortwavelengths respectively. The green peak position (GPP) and red trough position(RTP) shifted about 8.5 and 6 nm respectively toward the longer wavelengths.Finally, the area of the red edge peak (the sum of derivative spectra from 680 to740 nm) and red edge position (REP) as the input vectors entered into C-SVC,which was an soft nonlinear margin classification method of support vectormachine, to recognize the healthy and diseased leaves. The kernel function wasradial basis function (RBF) and the value of punishment coefficient (C) wasobtained from the classification model of training data sets (n=138). Theperformance of C-SVC was examined with the testing sample (n=126), and healthyand diseased leaves could be successfully differentiated without errors. Thisresearch demonstrated that the response feature of spectral reflectance wasobvious to disease stress in rice leaves, and it was feasible to discriminatediseased leaves from healthy ones based on C-SVC model and hyperspectralreflectance.Christie; Derivative spectrum; Support vector classification machine(SVC)

The canopy spectral reflectance and chlorophyll content of corn weremeasured and analyzed under different nitrogen treatments. The trends ofchlorophyll content were discussed based on different growth stages and differentnitrogen levels. It was observed that the chlorophyll content increased with theincrease in nitrogen, and could be affected by the environment changes includingthe temperature, rain, fertilizer treatment and so on. The characteristics ofcanopy spectral reflectance indicated that the canopy spectral reflectancechanged significantly at different stages. In the visible region (400-750 nm),the reflectance increased and reached the maximum until the shooting stage, anddecreased subsequently with the growth progress. In near-infrared region (750-1000 nm), the spectral reflectance climbed sharply. It increased from tilleringstage to shooting stage first, and then began to decline at trumpet stage and wasraised again at anthesis-silking stage. At milking stage, the reflectance wasdecreased again. There were clear distinctions of visible reflectance indifferent nitrogen regions. At shooting stage, with the increase in nitrogen thereflectance decreased at chlorophyll absorption band (430-450 nm, 640-660nm).Investigating the reflectance of the corn canopy under the different nitrogentreatment, it was found that the reflectance was higher in normal fertilizingregion than others in 550 nm, with RNormal>RLow>RHigh. At trumpet stage, thecanopy reflectance in low fertilizing region was higher than others in thevisible region. It was clear that the corn canopy reflectance of normalfertilizing region was the same as high fertilizing region. The results indicatedover fertilizing could not help increase the corn nitrogen uptake. The studyprovided the basic information of chlorophyll measurement based on spectraltechnology and could help to guide the precision fertilizer in the field.

Highly fluorescent and stable ZnSe quantum dots were synthesized by afacile colloid aqueous phase route. It overcame the defects such as instabilityand low quantum yields of the quantum dots synthesized by early aqueous phaseroute. Optimum conditions were found. L-glutathione was used as the stabilizer,the molar ratio of L-glutathione, Se2- and Zn2+ is 5∶1∶5, the reaction media ispH 10.5, and the proper temperature is between 90 and 100 ℃. Quantum yields(QYs) could reach to 50.1% without post irradiation in prime syntheticalconditions. And the fluorescence intensity of ZnSe QDs almost didn’t changeafter 3 months. Its water-soluble property is also excellent. The properties ofZnSe QDs were characterized by means of ultraviolet visible spectra, fluorescencespectra, and transmission electron microscopy. The synthesized ZnSe QDs emitblue-purple fluorescence (370 nm) when excited at 300 nm. And the excellentphotochemical characteristics of the ZnSe QDs will be advantageous in theapplication in optothermal device manufacture and chemistry biology domain.

In the present paper a new 5-nitrosalicylaldehyde was prepared by thereaction of salicylaldehyde with mix acid, and this semicarbazide Schiff baseligand and its complex containing Cu(Ⅱ) and Ni(Ⅱ) were synthesized. Itscompositions and structure were characterized by elemental analyses, thermalanalyses,IR spectra and UV spectra,1H NMR and molar conductivity. The dismutationto O－2 free radical was also investigated. The result shows that the structureand thermodynamic properties were stable. The complexes showed a distinct -2scavenging effect and some protective effects on hemoglobin of human erythrocytein the system of -2 generating riboflavin with irradiation.Zinc(Ⅱ)

Models based on microfacet were used to describe spectropolarimetricBRDF (short for bidirectional reflectance distribution function) withexperimental data. And the spectropolarimetric BRDF values of targets weremeasured with the comparison to the standard whiteboard, which was considered asLambert and had a uniform reflectance rate up to 98% at arbitrary angle of view.And then the relationships between measured spectropolarimetric BRDF values andthe angles of view, as well as wavelengths which were in a range of 400-720 nmwere analyzed in details. The initial value needed to be input to the LMoptimization method was difficult to get and greatly impacted the results.Therefore, optimization approach which combines genetic algorithm and Levenberg-Marquardt (LM) was utilized aiming to retrieve parameters of nonlinear models,and the initial values were obtained using GA approach. Simulated experimentswere used to test the efficiency of the adopted optimization method. And thesimulated experiment ensures the optimization method to have a good performanceand be able to retrieve the parameters of nonlinear model efficiently. Thecorrectness of the models was validated by real outdoor sampled data. Theparameters of DoP model retrieved are the refraction index of measured targets.The refraction index of the same color painted target but with differentmaterials was also obtained. Conclusion has been drawn that the refraction indexfrom these two targets are very near and this slight difference could beunderstood by the difference in the conditions of paint targets’ surface, notthe material of the targets.BRDF； Microfacet model等学校博士学科点专项科研基金项目(20060699032), 航空科学基金项目(2007ZC53037)和西北工业大学英才计划基金项目资助

Alkali-alkaline earth borate LiCaBO3∶Ce3+, LiSrBO3∶Ce3+ and LiBaBO3∶Ce3+ were investigated by solid-state method. CaCO3(99.9%), SrCO3(99.9%), BaCO3(99.9%), Li2CO3(99.9%), Na2CO3(99.9%), K2CO3(99.9%), H3BO3(99.9%) and CeO2(99.9%)were used as starting materials, After these individual materials were blendedand ground thoroughly in an agate mortar, the homogeneous mixture was heated at700 ℃ for 2 h in a reduced atmosphere (5∶95(H2/N2)), and these three phosphorswere obtained. The excitation and emission spectra of these phosphors weremeasured by a SHIMADZU RF-540 fluorescence spectrophotometer. The spectralcharacteristics of Ce3+ in alkali-alkaline earth borate LiCaBO3, LiSrBO3 andLiBaBO3 were investigated. The emission spectra of Ce3+ in these three phosphorsall exhibited a dissymmetrical band, and the emission peaks were located at 428,436 and 440 nm, respectively. The excitation spectra for 428, 436 and 440 nmemission of these three phosphors showed a dissymmetrical band at 364, 369 and370 nm, respectively. The effects of Li+, Na+ and K+ on the emission intensitiesof these three phosphors were studied. The results show that the emissionintensities of these phosphors were enhanced, and the maximal emission intensityof doping Li+ is higher than that of Na+ and K+.教育厅基金项目(2009313)资助

The authors set up an experiment instrument to measure the ultraviolet(UV) characteristic of oil spill simulation targets for the marine oil spill.After selecting appropriate conditions for experiments, the authors tested UVreflective spectrum of four simulation targets for oil spill (gasoline, kerosene,diesel fuel, lubricating oil). The authors calculated the UV absolute spectrumreflectivity of all testing targets from the standard white board as reference,whose UV reflectivity was given. With processing and analyzing the data fromexperiments, the authors got the reflective characteristics of them in contrastto the reflectivity of water, which was measured in the same conditions. Alltargets were tested from 320 to 400 nm, and UV reflectivity wave-band between 360and 380 nm was representative. Testing data were shown as follows: (1) Thereflectivity of water was from 5.3% to 5.5%. (2) When the thickness of oil filmwas 400 μm, the reflectivity of gasoline was from 8.5% to 8.8%, 5.4%-5.8% forkerosene, 8.3%-8.4% for diesel fuel, and 9.4%-9.7% for lubricating oil in thesame wave-band between 360 and 380 nm. Correspondingly, the indeterminacy ofreflectivity was 0.32%, 0.45%, 0.25%, and 0.33% respectively. (3) Hence thethickness of oil film changed, the rule of the UV reflectivity varied dependingon the sort of oil spill. The results show that there were some obviousreflectivity differences among oil films and water, which were mainly determinedby the sort and thickness of oil film. This experiment method is also fit for theactual oil spill target, and it will fulfill some theory and experimentalfoundation for inspecting the marine oil spill by UV remote sensing in thefuture.targets(40776100)资助

Endmember (EM) selection is an important prerequisite task for mixedspectral analysis of hyperspectral imagery. In all kinds of EM selection methods,N-FINDR has been a popular one for its full automation and efficient performance.Unfortunately, the implementation of the algorithm needs dimensional reduction inoriginal data, and the algorithm includes innumerable volume calculation. Thisleads to a low speed of the algorithm and so becomes a limitation to itsapplications. In the present paper, an improved N-FINDR algorithm was proposedbased on linear least square support vector machines (LLSSVM), which is free ofdimensional reduction and makes use of distance measure instead of volumeevaluation to speed up the algorithm. Additionally, it was also proposed to endowthe algorithm with robustness by controlling outliers. Experiments show that thecomputational load for EM selection using the improved N-FINDR algorithm based onLLSSVM was decreased greatly, and the selection effectiveness and the speed ofthe proposed algorithm were further improved by outlier removal and the pixelpre-sorting method respectively.support vector machines(LLSSVM); N-FINDR algorithm水下智能机器人技术国防科技重点实验室项目资助

In the present article, NaGDC was used to study the Ca2+-bufferingcapability of bile salt micelles. NaGDC is a naturally occurring bile salt whichconstitutes approximately 10 molar percent of bile salt composition ingallbladder. The authors selected glycine conjugated bile salts NaGDC because itprecipitates with Ca2+ ions fast. The Ca2+-buffering property of sodiumglycodeoxycholate (NaGDC) micelles was studied by utilizing turbidity titration,quasi-elastic light scattering (QELS), transmission electron microscopy (TEM) andFourier transform infrared spectroscopy (FTIR). When the concentration of NaGDCwas above the CMC, the precipitation of Ca2+ ions with NaGDC was buffered. TheCa2+-buffering capability was enhanced when the concentration of NaGDC increased.The possible mechanism of Ca2+-buffering by NaGDC micelles was discussed. Whenthe concentration of NaGDC was below the CMC, the Ca2+ ions reacted with GDC-anions to form the Ca(GDC)2 precipitation. However, at the concentration abovethe CMC, NaGDC simple micelles were connected by Ca2+-bridge to form largerfibriform micelles via the interaction of carboxyl groups of NaGDC simplemicelles with Ca2+ ions. When the ratio of Ca2+ to Na+ was enhanced to the fixedvalue, NanCam(GDC)n+2m complexes were precipitated by the further addition ofCa2+ ions.

Polycrystalline CdTe thin films were prepared by close-spacedsublimation (CCS) and were annealed in different condition. The thin films werecharacterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) andX-ray photoelectron spectroscopy(XPS). The content distribution and valence stateof all elements after annealing were studied. All results show that the as-deposited CdTe thin films are in a cubic phase and have the preferred orientationin (111) direction. After annealing, the peak intensity of (111), (220), (311)grows and the crystal grains grow up, while the crystal boundary decreases. Sothe compound probabilities of current carrier decrease, therefore shuntresistance and drain current are improved. From detailed analysis of X-rayphotoelectron data, it is proposed that tellurium oxides present and its contentreduces with depth increasing and that there are TeCl2O building blocks.础项目(2006J13-083)资助

The research object of the present paper is the water quality of HanShiqiao wetland water. Water spectrum and quality parameters were measured on thesite and in the lab. The authors simulated the relationships between waterquality parameters and the best bands or combination, and built the multiplelinear regression equation to obtain characteristic spectrum of the key waterquality parameters. Besides, several key issues involved in applying ASTERsatellite imagery to water quality include atmospheric correction, discussingmethods for ASTER data bands analysis, and choosing the best bands and bandcombination. Results indicated that although the simulation model is notuniversal, the analysis of spectral characteristics based on ground spectrometercould provide foundations for the choice of remote sensing characteristics bands.The band ratio of water quality parameters simulated from ASTER spectralcharacteristics moves to relatively long-wave band. Finally, based on theanalysis of ASTER remote sensing characteristics bands, the authors built waterquality parameters regression model. The models for water quality parameters wererecommended, and the accuracies of these models were analyzed. Making use ofregression model, we executed spatial distribution map of water qualityparameters to achieve wetland water monitoring with remote sensing in terms ofvariation in space and with time.Semi-empirical algorithms(2006BAD10A06-03, 2006BAB15B05)资助

In the present paper, a laboratory-made high-performanceelectrophoresis microcolumn unit was prepared for UV-Vis spectrophotometer. X-raydiffraction was used in the preparation of electrophoretic microcolumns. And ananalytical technique of microcolumn electrophoresis coupled with UV-Visspectrophotometry was introduced. Uniform quartz microncrystals were prepared byhydrothermal synthesis. Their crystalline phase and morphology were identified byX-ray diffraction and scanning electron microscope, respectively. The quartzmicroncrystals were packed into a 2-mm i.d. fused-silica tube to prepare theelectrophoretic microcolumn. With 1.5 mmol?L-1 disodium phosphate buffersolution (pH 11.5) containing 25% (φ) methanol and 10% (φ) acetonitrile,tryptophan, phenylalanine and tyrosine were on-line separated on line anddetected by microcolumn electrophoresis coupled with UV-Vis spectrophotometrywithout derivatization. The limits of detection were 0.037, 0.20 and 0.20 μmol?L-1, respectively. The separation efficiency of tryptophan was 4.5×104 plates/m.The sample capacity of the electrophoretic microcolumn achieved 35 μL. It wasfound that the electrophoretic microcolumn packed with quartz microncrystals wasable to limit Joule heat, increase sample capacity and enhance detectionsensitivity. The laboratory-made electrophoretic microcolumn could be a high-performance separation unit for conventional UV-Vis spectrophotometer. The on-line coupling of microcolumn electrophoresis and UV-Vis spectrophotometry couldseparate and determine samples with complicated matrices, reduce zone broadeningand enhance separation efficiency, so expand the analytical function ofspectrophotometer in the trace analysis of mixed components with overlappedspectra.spectrophotometer; Hydrothermal synthesis; Quartz microncrystals; X-raydiffraction; Amino acids

Anatase-type TiO2 fine powders were synthesized under hydrothermalcondition. The precursor was obtained via precipitation route using Ti(SO4)2. Thecharacterization of the as-prepared sample was confirmed by TEM, XRD, UV-Vis andlow temperature N2 adsorption measurements(BET). The photocatalytic activity wasalso investigated by the degradation of methyl orange solutions. The particles ofthe as-synthesized sample with narrow size distribution had an average diameterof about 24 nm. The specific BET surface area of the as-synthesized sample wasabout 56 m2?g-1,which is similar to the commercial TiO2(P25). The preparedmaterials showed the similar photocatalytic activity when compared with theperformance of commercial TiO2(P25).(20060001032), 国防科工委军工遗留专项基金(科工计［2007］840)项目和国家大学生创新训练计划项目资助

An innovative technology of spectral navigation is presented in thepresent paper. This new method adopts reflectance spectra of fruits, leaves andbranches as one of the key navigation parameters and positions the fruits offruit trees relying on the diversity of spectral characteristics. The researchresults show that the distinct smoothness as effect is available in the spectrumof leaves of fruit trees. On the other hand, gradual increasing as the trend isan important feature in the spectrum of branches of fruit trees while thespectrum of fruit fluctuates. In addition, the peak diversity of reflectance ratebetween fruits and leaves of fruit trees is reached at 850 nm of wavelength. Sothe limit value can be designed at this wavelength in order to distinguish fruitsand leaves. The method introduced here can not only quickly distinguish fruits,leaves and branches, but also avoid the effects of surroundings. Compared withthe traditional navigation systems based on machine vision, there are still somespecial and unique features in the field of positioning the fruits of fruit treesusing spectral navigation technology.Navigation parameters合作计划项目(BZ2008060)和国家留学基金项目(2008104769)资助

According to the difficulty in selecting parameter of least squaresupport vector machine (LS-SVM) when modeling on the gas mixture, and the highcomputational complexity of the infrared spectrum data, LS-SVM optimized byparticle swarm optimization (PSO) algorithm was proposed to build an infraredspectrum quantitative analysis model with feature extracted by principalcomponent analysis (PCA). Firstly, seven feature variables were extracted by PCAas the input of the model from 550 infrared spectrum data of the main absorptionapex field, so the computational complexity was reduced. This model aimed atthree components of gas mixture, in which methane, ethane and propane gases areincluded. The concentration of each component ranged from 0.1% to 1%, 0.1% to 1%and 0.1% to 1.5% respectively. Each component quantitative analysis model wasbuilt by LS-SVM and the parameters were optimized by PSO algorithm, then theregression model would be reconstructed according to the optimal parameters. Thismethod replaced the traditional ergodic optimization. The experiment results showthat the time of offline modeling by PSOwas reduced to one fortieth of that ofergodic optimizing. The precision of the model was corresponsive. It can meet therequirement of the measure. PSO algorithm has more superior performance on globaloptimization and convergence speed. So it is feasible to combine PSO algorithmwith LS-SVM to create the infrared spectrum quantitative analysis model. It hasdefinite practice significance and application value.square support vector machine; Quantitative analysis; Gas mixture; Principalcomponent analysis

In order to study wear characteristics of a 6-cylinder diesel engine,six different working statuses were arranged by altering the clearance betweencylinder and piston. Sixty-nine oil samples were taken from engine at differentloads under 6 working statuses and analyzed by Spectroil M Instrument made in US.Principal component analysis (PCA) was applied to analyzing spectrometric data ofsixty-nine oil samples and clustering those data according to elements and oilsamples separately based on the weighted coefficient and principal componentscores. All 21 elements were used in element clustering and only 6 wear-relatedelements, namely iron, chromium, aluminum, copper, plumbum and silicon, were usedin sample clustering. It is shown that PCA effectively clustered oilspectrometric data into three different principal components according toelements. The projection of two different principal components exhibited fivetypes of elements combinations, namely wear elements (Fe, Cr, Cu, Al and Pb),high concentration additives elements (Na, Zn, P, Ca and Mg), low concentrationadditives elements (Ba and B), base constituent of lubricating oils (C and H) andinterferential elements (Ni, Ti, Mo, V, Ag and Sn). Furthermore, PCA clearlyclustered oil samples according to different clearance between cylinder andpiston in the diesel engine. The study suggests that analyzing oil spectrographicdata by PCA could find the sources of different elements,monitor engineconditions and diagnose wear faults.Diesel engine; Lubricating oil

The laser-induced breakdown spectroscopy (LIBS) technique is a fast,non-contact method with no need for any sample preparation, and can be carriedout under various atmospheric conditions. These properties make LIBS applicableto process control in metallurgy. In the present paper, a series of high alloysteel GBW01605—01609 samples were determined by laser induced plasmaspectroscopy, based on a Nd∶YAG Q-switched solid laser with wavelength 1 064 nmas an excitation source and CCD as detector. Experimental study on theinteraction between laser and high alloy steel samples was completed. The effectson LIBS in high alloy steel such as observation distance and laser power densitywere systematically studied. The time-resolved spectrum of LIBS was alsoinvestigated. The optimum experiment conditions for the application of LIBS tothe trace analysis in high alloy steel were obtained firstly.alloy steel(O8A3260301)资助

In the present study, the system of nonradioactive iodine-labeled-antibodies linking inductively coupled plasma mass spectrometry for immunoassaywas reported. The goat-anti-Escherichia coli and goat anti rabbit were consideredas simulant antigen and antibody respectively in order to establish a new methodof immunoassay by inductively coupled plasma mass spectrometry which has theadvantage of high sensitivity, low detection limit and preferable linearityrange. During the experiment, the N-bromosuccinimide, a mild oxidant, was used tooxidize the non-radioactive iodine (127I) that labeled the protein. The method ofnonradioactive iodine labeled protein was established and the best labelingcondition was explored. The compound of I was purified by Sephadex G50 columnchromatography, then the stability and activity were examined. The results showedthat the labeling program was simple, reaction time was within two minutes, thelabeling yield achieved 63.12% and none of I shed from the compound after 96hours. The simulant antigen and antibody reacted on polystyrene microtiter plateand the I was detected by ICP-MS, the detection limit of the method was 0.12 mg?L-1, relative standard deviation (n=9) was less than 3% and the linearlydependent coefficient was 0.998 7. This system can also be used in analysis ofother protein, nucleic acid and so on.环境保护及节能减排专项项目资助

A new type of surface ion-imprinted polymer was synthesized in aqueousmedia with sodium trititanate whisker in the presence of Cd(Ⅱ), chitosan and γ-glycidoxypropyl trimethoxysilane (KH-560). A batch of adsorption experimentswere performed to evaluate its adsorption of Cd(Ⅱ) using inductively coupledplasma atomic emission spectrometry (ICP-AES). The factors affecting adsorptioncapacity, including pH and sorbent amount, were discussed. The adsorptionkinetics and adsorption isothermals were also obtained. The Langmuir isotherm canfit in the experimental equilibrium data. Under the optimum conditions, the valueof the adsorption was above 99 %, and the maximum adsorption capacity was 52.34mg?g-1. In accordance with the parameters distribution coefficient (Kd) andselectivity coefficient (K), the selectivity for Cd(Ⅱ) of the prepared imprintedpolymer was estimated. Finally, the adsorption mechanism was discussed and thedetection limit of 0.024 μg?mL-1 with the relative standard deviation (RSD) of1.74% (ｃ=1.0 μg?mL-1, n=13) for Cd(Ⅱ) was obtained. Results showed that thesurface Cd(Ⅱ)-imprinted polymer was a solid sorbent with high efficiency, low-cost, convenient separation/enrichment for environmental trace Cd(Ⅱ).spectrometry; Adsorption; Cadmium (Cd(Ⅱ))学技术基金项目(05C26213100474)资助

The compositions and contents of chemical compounds in traditionalChinese medicines would be changed after being processed using different methods,and their pharmacological activity may be influenced. ICP-AES, AAS and AFS werethe first methods to be used to scan and analyze macro elements, trace elementsand heavy metals in Foeniculum vulgare and its nine different processed samplesin the present paper, which were correlated with people’s health and lives. Theexperiment results showed that the three kinds of analyzing methods could be usedto judge the contents and the changing trend of all elements in traditionalChinese medicine quickly and truly. Thirty two elements were found in F. vulgare,and there were noticeable changes in the contents of some elements in processedsamples compared with F. vulgare without processing. These results indicated thatthere is great relevance between changes in the contends of elements withdifferent processing methods, and auxiliary materials can not only change thecontents of elements but also play a role in treating ills with effectiveconstituents. Also, it was firstly found that the content of Hg rose greatly inthe experiment, and these showed there was notable potential safety hazard whenprocessed Foeniculum vulgare was used. These experiments widen the application ofspectrum analyzing methods in safety evaluation of traditional Chinese medicine.范大学化学生物学及中药分析教育部重点实验室开放基金项目(KLCBTCMR2008-03)资助

The root and rhizome of danshen (salvia miltiorrhiza bunge), one of theearliest and also the most commonly used herbal drugs in practice of traditionalChinese medicines, has been confirmed effective for coronary heart disease,including angina pectoris, coronary artery spasm, myocardial infarction, etc.,based on modern investigations. And some trace elements were found related tothese diseases. Therefore it was important to research trace elements and theircontents in the root for studying pharmic mechanism of danshen. The contents of22 trace elements, including Ca, Mg, Fe, Zn, V, Mn, Cr, Cu, Rb, Sr, Ba, Pb, B,As, Se, Li, Co, Ni, Mo, Cd, Sn and Hg, in the roots of danshen germplasm,originating from four planting regions and grew in the same place, were analyzedby ICP-MS/ICP-AES. The results showed that the contents of trace elements in theroot of Shandong white flower danshen were higher as a whole. And the contents ofCa, Fe, Zn, Mn, Cu, Ba, Li, Co, Ni and Hg in the root of Shandong white flowerdanshen were the highest among the four kinds of original danshen,in which thecontents of Zn, Mn, Cu, Ni and Hg were significantly higher than those in thethree kinds of original violet flower danshen. The contents of Rb and Mo in theroot of Shanxishangluo violet flower danshen were the smallest and that of Ni wasthe highest among the three kinds of original violet flower danshen. Comparedwith the difference between white flower danshen and violet flower danshen, thedifference of rest nineteen kinds of trace elements contents among the threekinds of original violet flower danshen was smaller. The difference in thecontents of trace elements has an important effect on the research into thecontents of officinal ingredients and their curative effect of the roots of fourkinds of original danshen germplasm.(20090450327)资助

A method of microwave digestion technique was proposed to determine thecontent of Zn, Fe, Cu, Mn, K, Ca, Mg, Ni, Cd, Pb, Cr, Co, Al, Se and As inlophatherum gracile brongn of different habitat by atomic absorptionspectroscopy. The RSD of the method was between 1.23% and 3.32%, and the recoveryrates obtained by standard addition method were between 95.8 ％and 104.2％. Theresults of the study indicate that the proposed method has the advantages ofsimplicity, speediness and sensitivity. It is suitable for the determination ofthe contents of metal elements in lophatherum gracile brongn. The experimentalresults also indicated that different areas’ lophantherum gracile brongn haddifferent trace elements content. The content of trace elements K, Mg, Ca, Fe andMn beneficial to the human body was rich. The content of the heavy metal traceelement Pb in lophantherum gracile brongn of Hunan province was slightly high.The content of the heavy metal trace element Cu in lophantherum gracile brongn ofGuangdong province and Anhui province is also slightly higher. Beside, thecontents of harmful trace heavy metal elements Cd, Cu, Cr, Pb and As inlophatherum gracile brongn of different habitat are all lower than the limits ofChinese Pharmacopoeia and Green Trade Standard for Importing and ExportingMedicinal Plant and Preparation and National Food Sanitation Standard. Thesedetermination results provided the scientific data for further discussing therelationship between the content of trace elements in lophantherum gracile brongnand the medicine efficacy.Lophatherum gracile; Trace elements(200510)资助

A flow injection- hydride generation-atomic absorption spectrometricmethod for the determination of selenium in poultry eggs was developed. Varioustesting conditions and effect factors for the determination of selenium werestudied. The authors also discussed the content of selenium in poultry eggs andthe application of scientific feed method in improving selenium content inpoultry eggs. The detection limit for selenium was 0.25 μg?L-1 under optimumconditions. The linear range for selenium was 0.25-60 μg?L-1. The relativestandard deviation was less than 2.5% and the recovery was 95%-108%. This methodovercame the problem of severe matrix interferences of graphite furnace atomicabsorption spectrometry, in which matrix modifier must be added to eliminatematrix interference by raising ashing temperature. Additionally this methodovercame the shortcoming of slow analysis procedure, complex operation and errorcaused by manual injection in traditional interval hydride generation-atomicabsorption spectrometry. It is a simple, rapid, highly sensitive and automaticmethod and has been applied to the determination of selenium in poultry eggs withsatisfactory results.Poultry eggs; Selenium; Determination of content

Microwave digestion technique was used in the decomposition of Ginkgobiloba leaves from six different trees at the same age in the same area. HNO3-H2O2 (5∶1 v/v) was used as microwave digestion agent at a suitable temperatureand time. The contents of Ca, Mg, K, Na, Cu, Zn and Zn/Cu were determined byflame atomic absorption spectrometry to study the distribution rule of metallicelements in the trees at the same age and in the same area. The recovery ratioranged from 95.2% to 104.6%. The results showed that there were certaindifferences between different trees in the distribution of metallic elements. Thecontents of calcium were from 39 586 to 48 320 μg?g-1, and those of magnesiumfrom 10 076 to 12 918 μg?g-1, of potassium from 2 004 to 5 240 μg?g-1, ofsodium from 9.05 to 35.30 μg?g-1, and of copper from 1.50 to 3.05 μg?g-1,while Zn/Cu values were from 2.68 to 5.93 in the leaves of 6 different trees inthe same growing area. Therefore there were abounding calcium, magnesium andpotassium, while the content of sodium and Zn/Cu values were lower, and the metalcontents were different in the leaves. The experimental results provided usefulbases for studying the distribution rule of metallic elements in Ginkgo bilobaleaves, the relationship between the contents of calcium, magnesium, potassiumand sodium and the Zn/Cu value in ginkgo biloba leaves and the treatment forcardio-cerebral vascular disease.

A simple and reliable method was developed for the determination ofserum copper and zinc in different chemical forms by graphite furnace atomicabsorption spectrometry (GFAAS) with ethanol-EDTA precipitation. The serum andethanol were mixed with volume ratio 1∶2. The mixture was incubated at 70 ℃ andultra-centrifuged to precipitate proteins. Zinc and copper can be released fromalbumin after EDTA treating. Thus, macroglobulin-zinc, ceruloplasmin-copper, andalbumin-bound zinc or copper could be determined by two proposed precipitationsteps. The determination limit of copper (3σ) was 1.2 μg?L-1 and the recoverywas 92.3%-104%, while the determination limit of zinc (3σ) was 0.098 μg?L-1,and the recovery was 90%-107%. This two-step precipitation method can be used todetermine serum zinc and copper in various chemical forms in tumor, Wilsonpatients and heathy human.

The changes in three endogenous hormones, phytohormones gibberrelicacid (GA3), indoles-3-acid (IAA) and abscisic acid (ABA), were studied aroundgermination and under tress of different density of Pb2+ between two species ofAmmopiptanathus. It was found that (1) around germination, in XinjiangAmmopiptanthus the rate IAA decreased 77.80%, and the rate of ABA decreased98.90%; and in Mongolia Ammopiptanthus the rate of IAA decreased 75.80%, the rateof ABA decreased 66.20%, and the GA3 contents in both had no big change. (2) Withthe increase in Pb2+ concentration (20-1 500 mg?L-1), the IAA decreasedsignificantly; and only under the high density (more than 1 000 mg?L-1) of Pb2+,the GA3 was affected by it; the ABA did not change regularly. So the threeendogenous hormone levels of Mongolia Ammopiptanthus were higher than those ofXinjiang Ammopiptanthus.(3)the distributions of Pb2+ in Ammopiptanthus seedlingsare the root＞stems＞leaves. (4) the stress of high concentration of Pb2+ damagesirreversibly the leaf cells of Ammopiptanthus. This study can provide the basisof reference data for further research on the growth characteristics, resilienceand the mechanism of specific broad-leaved evergreen shrubs-Ammopiptanthus indesertification area.(XJEDU2004I08), 土壤学新疆自治区重点学科项目资助

Due to the impact of lead-zinc mining and smelting, the soil of lead-zinc orefield and nearby areas has been widely polluted. Moreover, theconcentration of lead and zinc was high, and their concentration range was wide.Furthermore, the impact of overlapping interference between low concentration Asand high Pb was serious, and the lack of soil standards of lead and zinc was alsoa problem. According to these problems, the present work studied an effectivesolution to setting up the EDXRF analysis of Pb, As, Cd, Cu and Zn of soil onlead-zinc orefield. The measurable concentration of Pb was 4.4-23 600 μg?g-1,and that of Zn was 7.0-39 400 μg?g-1. The detection limit was 1.1 μg?g-1 forPb and 0.9 μg?g-1 for Zn. The average relative error was 7.6% for Pb and 6.2%for Zn.fluorescence (EDXRF)

A rapid multi-element analysis method for clay mineral samples wasdescribed. This method utilized a polarized wavelength dispersive X-rayfluorescence spectrometer—Axios PW4400,which had a maximum tube power of 4 000watts. The method was developed for the determination of As, Mn, Co, Cu, Cr, Dy,Ga, Mo, P, Pb, Rb, S, Sr, Ni, ,Cs, Ta, Th, Ti, U, V, Y, Zn, Zr, MgO, K2O, Na2O,CaO, Fe2O3, Al2O3, SiO2 and so on. Thirty elements in clay mineral species weremeasured by X-ray fluorescence spectrometry with pressed powder pellets. Spectralinterferences, in particular the indirect interferences of each element, werestudied. A method to distinguish the interference between each other periodicelements in element periodic table was put forward. The measuring conditions andexistence were mainly investigated,and the selected background position as wellas corrected spectral overlap for the trace elements were also discussed. It wasfound that the indirect spectral overlap line was the same important as directspectral overlap line. Due to inducing the effect of indirect spectral overlap,some elements jlike Bi, Sn, W which do not need analysis were also added to theelements channel. The relative standard deviation (RSD) was in the range of 0.01%to 5.45% except three elements Mo, Cs and Ta. The detection limits, precisionsand accuracies for most elements using this method can meet the requirements ofsample analysis in clay mineral species.mineral； Reference material科发人教字)资助

The effects of dynamic ultra high-pressure microfluidization on thestructure of waxy rice starch solutions (6%) were analyzed using SEM, UV-Visspectra, polarized light microscopy, and X-ray diffraction spectra. The resultsshowed that: SEM graphs demonstrated that the crystal structure of waxy ricestarch under different pressure treatment was destroyed with different degreesand impacted into flake up to 160 MPa; from the ultraviolet-visible spectrum weknow the reduction in the blue iodine value and the decrease in the amylopectincontent, which illustrated that the structure of waxy rice starch was fractured;polarized microscopic images showed that the polarization crosses of starchmolecules became misty with the pressure increasing, and most of starch moleculeslost polarization cross when the pressure reached 160 MPa; X-ray diffractionspectra indicated that relative crystallinity began to decline at 120 MPa withpressure treatment, and the decreased amplitude was slightly lower.spectra(IRT0540)资助

The rapid development of astronomical observation has led to many largesky surveys such as SDSS (Sloan digital sky survey) and LAMOST (large sky areamulti-object spectroscopic telescope). Since these surveys have produced verylarge numbers of spectra, automated spectral analysis becomes desirable andnecessary. The present paper studies the spectral classification method based onBayes decision theory, which divides spectra into three types: star, galaxy andquasar. Firstly, principal component analysis (PCA) is used in featureextraction, and spectra are projected into the 3D PCA feature space; secondly,the class conditional probability density functions are estimated using the non-parametric density estimation technique, Parzen window approach; finally, theminimum error Bayes decision rule is used for classification. In Parzen windowapproach, the kernel width affects the density estimation, and then affects theclassification effect. Extensive experiments have been performed to analyze therelationship between the kernel widths and the correct classification rates. Theauthors found that the correct rate increases with the kernel width being closeto some threshold, while it decreases with the kernel width being less than thisthreshold.(201008282)资助

The light emitting diode (LED) chip spectrum inspection is a keytechnology in LED chip scaled manufacturing. According to the principle ofspectrum inspection and aiming at the demand of applications of LED chip spectruminspection, the present paper studies the spectrum acquisition system based oncomplex programmable logic device (CPLD). The CPLD, the main chip, provides theworking timing signal to the linear charge coupled device (CCD) and controls thesignal modulating, conversion and storage, and transmission of sampling rate anddata in transfer module. The system adopts raster monochromator as prismaticparts of apparatus and linear CCD as photoelectricity conversion parts to inspectthe opposite spectrum energy distributing curve, and meanwhile calculate thespectrum parameter of LED chip photics characteristic. Based on the CPLD , theLED chip spectrum acquisition system with the virtues of simplicity and celeritysatisfies the precision request of LED chip spectrum inspection.

A novel near-infrared spectrum detection system based on grating lightmodulators is proposed in the present paper. A new spectrum detection method thatcombines MEMS grating light modulators with a single near infrared detector isapplied in the system, which can avoid using costly near infrared detector array.Firstly, the optical structure of the spectra detection system was designed.Secondly, the spectra detection principle of this system was addressed in detailthat with a series of voltages actuated on the grating light modulators array,the optical energy of each wavelength is reflected onto the single near-infrareddetector by corresponding grating light modulator pixel orderly and thetransmission spectra can be acquired after a scanning period. Finally, thegrating light modulators array device was fabricated by surface micromachiningprocessing and a near-infrared spectra detection system was set up to test thekey parameters such as resolving power, wavelength accuracy, system stability andresponse characteristics of grating light modulators. The experimental resultsilluminated that the spectrum range of this spectra detection system is from 1320 to 1 400 nm, the resolving power is below 10nm, the wavelength accuracy iswithin 1nm,the stability of the system is below 0.5% and the response frequencyis 5 kHz. The results of theory analysis and experiments demonstrated thefeasibility of the spectra detection system. It could give theoretical andexperimental guidance to the design and fabrication of miniature near-infraredspectrometer based on grating light modulators.MEMS

The new scheme of using a long period grating for simultaneousdiscriminating measurement of temperature and strain is proposed. The scheme isbased on the long period grating’s spectrum characteristics. The spectrum iscomposed of multiple and different loss peak. The resonant wavelength of thefirst and fourth-order loss peak with different temperature and strainsensitivity was selected in this experiment. The wavelength shift resulting fromparameter variation can be obtained by observing its corresponding spectrum. Thetemperature was acquired by a study on the temperature characteristic of a LPG.The strain sensitivity was obtained by the research on the strain characteristicof a LPG. The standard matrix equation was set up and solved according to thecorresponding parameter. The authors know by calculating the standard matrixequation that the cross-sensitivity has little influence on the measurement ofthe parameter. As the effect of cross-sensitivity is lower than the resolution ofthe LPG in this case, we can eliminate the deviation due to the cross-sensitiveby appropriate compensation. The errors of temperature and strain were calculatedto be ±0.92 ℃ and ±22 με respectively. The cross-sensitivity betweentemperature and strain was decreased and the measuring precision of the systemwas improved by using this scheme in which a single long period grating was usedto test two measurands. By comparison between the applied and the calculatedtemperature and strain of a LPG, the experiment results showed that the methodsare feasible.The experimental system is small and the cost is relatively low. Theexperimental device is simple and practical and has good application prospect.Simultaneous measurement; FiberBK2009370), 航空科学基金项目(2008ZD52047)和南京航空航天大学研究生创新基地(实验室)开放基金项目(200901001)资助

Fourier transform imaging spectrometer is a new technic, and has beendeveloped very rapidly in nearly ten years. The data catched by Fourier transformimaging spectrometer is indirect data, can not be used by user, and need to beprocessed by various approaches, including data pretreatment, apodization, phasecorrection, FFT, and spectral radicalization calibration. No paper so far hasbeen found roundly to introduce this method. In the present paper, the authorwill give an effective method to process the interfering data to spectral data,and with this method we can obtain good result.processing究员

In the static interferometer system, the variable refractive crystalLiNbO3 with electro-optic modulation was used in static Fourier transforminterferometer, where both sides load phase opposite modulation signal separatelyso to raise the spectrum resolution in the same size of the instrument by theincrement of optical path difference. According to the derivation of the opticalpath difference function with refraction modulation, the maximum optical pathdifference was calculated and the spectrum resolution was analyzed to be 16.7times previous one when the refraction modulation was 0.030 in the same size ofinterferometer. The simulation result indicated that the refractive modulationwould be reduced when the wavelength increased, and the value of optical pathdifference will be bigger when the x′ increased. In actual detection process,because spectral region 500-1 100 nm is relatively narrow, the spectrumdistortion by the wavelength change is not big and may be compensated through thedemarcation. This method can increase the optical path difference withoutmechanical scanning, and possibly raises spectrum resolution of the staticinterferometer.-optic modulation; Spectrum resolution