Aiming at the challenge of how oral drug delivery systems protect drug molecules from environmental influences in human body, a pH value-sensitive sodium alginate-montmorillonite composite microsphere (MMT/SA) was synthesized by an emulsification gel method, which was used to load anticancer drug doxorubicin hydrochloride (DOX), and overcome the biochemical barrier of gastrointestinal tract while protecting drug molecules. The effect of raw material (MMT pretreatment and content) on the morphology of microspheres was investigated, and the size of microspheres with a uniform distribution was controlled to be 20 μm. The drug loading rate of DOX/MMT/SA is 14.7%, indicating different drug release effects in simulated gastric juice and artificial intestinal juice. The cumulative release rate of DOX/MMT/SA in simulated gastric juice (i.e., 31.7%) is greater than that in artificial gastric juice (i.e., 15.8%), and it has a killing effect on the cancer cells.

Natural molybdenite has the advantages of low cost and high lithium storage capacity, which can be directly used as an anode material of lithium-ion batteries. In this paper, expanded molybdenite/carbon (EM/C) composites were constructed via expanding molybdenite and surface modification with dopamine. The worm-like structure of expanded molybdenite (EM) has a high specific surface area that is conducive to electrolyte infiltration and diffusion of lithium ions. The amorphous carbon layer effectively increases its electrical conductivity and provides a buffer space for volume enlargement during MoS2 cycle. The EM/C composites have a long cycle life and a high capacity, with a capacity of 1 213 mA·h/g at 100 mA/g after 200 cycles and a reversible capacity of 623 mA·h/g even at 1 A/g. The strategy of EM/C composite material constructed from molybdenite fine powder has a specific guiding significance to achieve the superior electrochemical performance of lithium-ion battery.

Nanozyme can quickly and sensitively detect biomarkers to prevent the outbreak of diseases. However, the low catalytic activity and poor affinity for substrates restrict the detection performance. Montmorillonite, as a typical 2:1 layered silicate clay mineral, has a good adsorption and cation exchange ability. Thus, Fe3+ can be anchored into the layers to prepare Fe doping montmorillonite nanozyme with a peroxidase-like property, enhancing the affinity for H2O2 and realizing the colorimetric detection of H2O2. The results show that the linear range and detection limit of H2O2 are 20-500 μmol/L and 5.8 μmol/L under neutral conditions, respectively. The colorimetric method for silicate clay mineral nanozyme has a good application prospect in the fields of analytical detection and disease diagnosis.

To obtain materials with superior antibacterial properties, Ag-ZnO/Talc ternary composite was prepared by a water-bath heating method with black talc (from Guangfeng, Jiangxi) as a matrix material. The composite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, respectively. Escherichia coli and staphylococcus aureus were used as the experimental strains. The antibacterial properties of the composite were examined by a plate counting method and a bacteriostatic zone method. The results show that the layered structure of talc sheet promotes the dispersion of nanoparticles and increases the contact area between the composite and bacteria. The Ag-ZnO/Talc composite displays a high antibacterial activity, and the antibacterial rate against escherichia coli and staphylococcus aureus reaches more than 99%.

Intercalation is a significant control method to achieve high value of kaolinite. It is important to investigate the intercalation process of kaolinite for the perspective of atomic and molecular scale and energy. This review represented recent work on theoretical calculation of intercalated kaolinite, i.e., the intercalation of inorganic and organic small molecules as well as organic macromolecular. In addition, the future development direction of intercalation of kaolinite was also prospected.

Lithium metal batteries are considered as one of the most promising energy storage batteries due to their high energy density. However, the growth of lithium dendrites in the lithium metal anode can lead to the capacity degradation and even safety problems. In this paper, attapulgite was loaded on fiber membrane for the application of lithium metal anode protection, assembling them into symmetrical cells and lithium iron phosphate full cells for electrochemical testing. The results show that the growth of lithium dendrites can be effectively inhibited due to the addition of attapulgite to the fibrous membrane. The polarization voltage of the symmetric cell is only 83.2 mV at a current density of 2 mA/cm2 and deposition capacity of 1 mA·h/cm2 for 500 h. The specific capacity of the full cell with attapulgite added to the fibrous membrane remains 84.92 mA·h/g after 1 000 cycles at 1 C. The inhibition of lithium dendrites by attapulgite provides an approach for the protection of lithium metal batteries with negative electrodes.

Lithium-rich cathode materials have attracted great interests due to their advantages, such as high energy density and wide voltage window. However, their shortcomings like low initial coulombic efficiency and poor cycle performance have hindered their commercial application. Lithium-rich cathode materials Li1.2Ni0.13Co0.13Mn0.54O2-xClx (x=0, 0.025, 0.050, 0.100) with different molar ratios of chloride ion (Cl-) doping were prepared by a co-precipitation method. The regulation mechanism of Cl- doping on the improvement of the electrochemical performance was investigated by X-ray photoelectron spectroscopy, in-situ X-ray diffraction and galvanostatic intermittent titration analysis. Compared with the pristine material, the initial coulombic efficiency of the cathode material with Cl-doping in a molar ratio of 0.05 increases from 72.8% to 81.5% at 0.2 C, and the capacity retention increases from 57.9% to 79.1% after 200 cycles at 1 C. It is indicated that Cl-doping can regulate the electrochemical behavior of O2- by oxidizing the more into On- (n<2) and less production of oxygen gas, thus reducing the structural deterioration. Meanwhile, the larger ion radius of Cl- can expand the layer spacing, reduce the polarization and accelerate the lithium ions diffusion in the lithium-rich and manganese-based cathode material, thereby enhancing the initial coulombic efficiency and the cycle performance.

Silicon has become the most promising anode material for lithium-ion batteries since its theoretical lithium intercalation capacity is as high as 4 200 mA?偸h/g. However, its commercial application as a negative electrode for Li-ion batteries is limited due to the huge volume expansion (≥300%) during intercalation and delithiation. In this paper, a C@Si/C silicon-based composite anode was prepared by an electrospinning technique with carbon source precursor coating. The phase structure and microstructure of the material were characterized by X-ray diffraction and scanning electron microscopy. The change of the quality of the obtained material after polyvinypyrrolidone coating with temperature was investigated by thermo-gravimetric analysis. Graphite transformation degree of the silicon-based negative electrode material obtained after carbonization was determined by Raman spectroscopy. The prepared silicon-based anode materials were analyzed by galvanostatic charge-discharge, cyclic voltammetry and alternating current impedance spectroscopy. The results show that the electrochemical performance of the carbon-coated electrospun Si/C fibers is improved compared to the uncoated fibers. At a current density of 0.1 A/g, the first discharge capacity can reach 1 401.4 mA?偸h/g, the first coulombic efficiency is as high as 70.22%, and the capacity remains at 582.6 mA?偸h/g after 100 cycles. The results of rate test show that after a large current density test of 1.0 A/g, C@Si/C silicon-based composite anode still has a reversible capacity of 622.2 mA?偸h/g at a current density of 0.1 A/g.

CH4 concentration of underground drainage coal mine methane is rather low, which is of the explosion risk and difficult to be used. Therefore, a safe and high-efficiency power generation method of low concentration coal mine methane (LC-CMM) was proposed based on the solid oxide fuel cell (SOFC). The deoxygenation and methane enrichment experiment based on the pressure swing adsorption (PSA) was conducted to eliminate the explosion risk of LC-CMM, the large-scale SOFC single cell experiment using the LC-CMM was carried out, and the multi-physics coupling model of SOFC was developed. The results show that the CH4 concentration can be increased by 1.36 times, the deoxygenation ratio can reach 84.5% through the PSA experiment, and the produced gas can meet the requirement of safe and efficient power generation of SOFC. The power density of large-scale single cell using LC-CMM can reach 110.2 mW/cm2, but the anodic carbon deposition occurs after the long-term discharging, thus causing the SOFC performance degradation. The results of numerical simulation show that the decrease of discharging voltage, the increase of volume ratio between O2 and CH4 of fuel and the decrease of fuel inlet rate can decrease the carbon deposition, but reducing the power generation performance of SOFC.

In order to construct a high-efficiency paper catalysts for soot removal, it is very important to design different active elements and realize the synergistic effects with the matrix fibers. A series of La1-xKxMnO3 (x = 0, 0.1, 0.2, 0.3, 0.4, 0.5) nanofiber catalysts were prepared via electrospinning. The oxidation performance of the catalyst for soot particles was examined by temperature programmed oxidation reaction. The defect effects induced by doping K+ ions in the LaMnO3 lattice on their catalytic performance evaluated by soot temperature-programmed oxidation were investigated by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and temperature programmed reduction analysis. The results show that all the nanofiber catalysts have a perovskite structure, while K2Mn4O8 as a new phase appears in the samples as x ≥ 0.3. The amount of active oxygen in the sample is affected by K+ ions replacing La3+ ions and Mn3+ ions transferring into Mn4+ ions. The replacement of A-site ions increases the degree of oxygen defects in the system, while the transformation of Mn3+ ions into Mn4+ ions determining the number of oxygen vacancies as a new phase can occur at a great content of K+ ions doped in the system. The sample La0.6K0.4MnO3 has an optimum catalytic activity at T50 of 347 ℃. The paper-structured catalyst prepared with a nanofiber to matrix fiber ratio of 1:1 has a good catalytic activity at T50 of 478 ℃.

In the field of catalysis, ZnO nanorods have attracted much attention because of their small size effect in the radial direction and the macroscopic characteristics of bulk materials in the longitudinal direction. In this paper, ZnO nanorods were synthesized by an improved solvothermal method, and Zn2 + ions and NaOH were added by a step-by-step method. The samples were characterized by X-ray diffraction and scanning electron microscopy. The mechanism of PEG-assisted synthesis of ZnO nanorods and the effect of NaOH addition on the morphology of ZnO nanorods were investigated. The desulfurization performance of ZnO nanorods with different length to diameter ratios was analyzed. The results show that the molecular weight of PEG has a significant effect on the morphology of ZnO nanorods. ZnO nanorods with a length of 3-4 ?倕 m and a diameter of approximately 250 nm can be synthesized under mild solvothermal conditions when the molecular weight of PEG is 20000. Also, the step-by-step method of adding NaOH is better than the one-step method of adding NaOH. NiO is loaded on the synthesized ZnO nanorods as a desulfurizer. The desulfurization rate of ZnO nanorods desulfurizer with a large length to diameter ratio can achieve 98.2%, and the desulfurizer has a better regeneration performance.

The effective joining between silicon nitride ceramics and metals is crucial for making full use of their excellent properties and meeting the service requirements of materials or components in complex environments. The gradient joining of silicon nitride ceramic (Si3N4) and molybdenum (Mo) with large physical properties difference was realized by a powder metallurgy gradient composite technology. The reaction mechanism of Si3N4 and Mo in each gradient layer under different sintering temperatures and Si3N4 additions was investigated. The transition layer structure of Si3N4/MoxSiy/Mo gradient material was optimized based on the reaction mechanism and the concentration distribution index p, obtaining the gradient connection of Si3N4 to Mo and improving the mechanical properties. The results show that Si3N4 and Mo mainly form molybdenum-silicon compounds through the diffusion reaction between Mo and Si. The reaction process follows (Mo+Si)→(Mo3Si/MoSi2+Si)→(Mo5Si3). The bending strength of Si3N4/MoxSiy/Mo gradient material reaches the maximum value of 371.42 MPa, the shear strength reaches the maximum value of 30.58 MPa, and the elements in the transition layer appear a quasi-continuous gradient distribution when p=1.5.

Preparation of hydrogenated tetrahedral amorphous carbon (ta-C:H) films with good mechanical properties by plasma-enhanced chemical vapor deposition (PECVD) is expected to meet requirement in industrial application. This paper reported the microstructure and mechanical properties of (ta-C:H) films prepared by a self-designed PECVD technique. As the bias voltage varies from -200 V to -500 V, the hardness and elastic modulus first decrease and then increase, reaching the maximum values of 34.0 GPa and 282.0 GPa respectively. The evolution of compressive stress with bias voltage shows a similar trend. In this case, the hardness and elastic modulus of films prepared by the self-designed PECVD technique both are improved, compared with those by the conventional PECVD methods. The mole fraction of sp3 hybridized bond is greater than 62.3% when the bias voltage changes from -200 V to -500 V. Carbon films were deposited using the self-designed PECVD technique, showing the typical characteristics of ta-C:H films. This can be attributed to the increased ion bombardment and ionization due to the incorporation of a water-cooled radio frequency double helix electrode and a plate electrode resulting in an enhanced sp3 content. This paper provides a promising technology to fabricate ta-C:H films with high hardness and elastic modulus for industrial applications.

Molybdenum is one of elements concentrated in power reactor high-level waste liquid. The dissolution of MoO3 in iron phosphate glass and the influence of MoO3 content on glass structure are the focus of researches on the iron phosphate glass formulation for immobilizing power reactor high-level waste liquid. To investigate the dissolution of MoO3 in iron phosphate glass and the effect of MoO3 content on the glass structure, a series of 60% P2O5-19%Fe2O3-8%Al2O3-13%Na2O(in mole fraction, the same below) samples doped with MoO3 at different ratios (i.e., 1%-8%) were prepared by a melting-quenching method. The phase and microscopic morphology were analyzed by X-ray diffraction (XRD) and electron probe microanalysis (EPMA). The structure of the samples was characterized by Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Mssbauer spectroscopy. Molybdenum can be completely dissolved into the glass structure without forming the crystallite and phase separation when the actual content of MoO3 is less than 6.38%. Molybdenum exists mainly in the form of ［MoM6］ octahedral in the glass, and Mo-O-P bonds are observed with the MoO3 content of more than 4%. The Q1 and Q2 units are the main structures in the glass phase, and the relative content of the Q1 unit increases with MoO3 doping content. The content of Fe3+ decreases slightly, while the valence state of Mo ions remains unchanged with the increase of MoO3 doping content.

Iron oxide dry desulphurization is an effective method for H2S removal. In this paper, three limonite materials from Yeshan, Xinqiao and Shao jilao iron mines were selected as desulfurizers for hydrogen sulfide removal. The effects of calcination temperature and reaction temperature on the desulfurization performance of limonite were investigated at medium-high temperatures, and a desulfurization cycle regeneration experiment was conducted. The removal mechanism of hydrogen sulfide was analyzed by X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. The results show that SJL-300 as an effective desulfurizer has a total desulfurization capacity of 1 525.7mg/g after seven cycles. In the evolution process of the reaction between limonite and hydrogen sulfide, pyrite and pyrrhotite are the desulfurization products at 300-400 ℃, while only pyrrhotite appears at > 500 ℃.

To investigate the problems of high loss of nickel metal in slag for nickel flash smelting, the mechanism of Fe/SiO2 ratio(mass ratio of Fe element to silica, hereinafter referred to as Fe/SiO2 ratio) on the separation characteristics of matte and slag was analyzed based on the bridge oxygen structure, FeO activity and valence change law of Fe in molten slag. The results show that the activity of FeO and the contents of Fe2+ and Fe3 + in nickel slag increase with increasing the addition of Fe/SiO2 ratio from 1.1 to 1.5. The increased Fe2+, Fe3+ and O2- promote the dissociation of complex silicate ion groups. The contents of Q1 and Q2 in silicate are reduced from 32.54% and 50.25% to 23.84% and 38.81%, respectively, while the content of Q0 is increased from 17.21% to 37.33%. The main structure of nickel slag is gradually transformed from a complex silicate structure to a Fe3+ connected SiO44- tetrahedron structure. The mass distribution ratio of Ni in matte and slag reaches the maximum value when m(Fe)/m(SiO2) = 1.2, which is greater than that of the original smelting slag under the same condition.

The acetaldehyde vapor produced in industrial production and life needs to be monitored in real time and efficiently, WO3 nanoplates and a series of Ti3C2Tx-WO3 composite materials were synthesized by a hydrothermal method. The structure and morphology of the as-prepared materials were investigated by X-ray diffraction, scanning electron microscopy, and X-ray photoelectron spectroscopy. The gas sensing properties of materials were analyzed. The results show that the addition of Ti3C2Tx can enhance the gas sensing performance of WO3 nanoplates. The optimized gas sensing operation temperature is 80 ℃ for 7%(mass fraction) Ti3C2Tx-WO3 composite material. The sensitivity of 7% Ti3C2Tx-WO3 composite material to 100 μL/L acetaldehyde vapor at 80 ℃ is 32.9 within a low detection limit of 0.1 μL/L.

The calcium leaching resistance of bonding interface between engineered cementitious composite (ECC) and existing concrete is a key issue in reinforcement engineering. A nitric acid solution of 0.5 mol/L was used to carry out the accelerated leaching test, and the time-dependent influences of interface treatment methods (i.e., roughening, wet saturation and interfacial agent) were investigated via indications of bonding strength, leaching depth and cumulative leached calcium ion. The improvement mechanism in micro scale was analyzed by scanning electron microscopy. The results show that the three interface treatment methods can effectively improve the bonding quality, and their time-dependent influences are similar. The bonding strength before leaching can be used to evaluate the leaching resistance of bonding interface. Roughening is more effective to improve the initial bonding strength, while interfacial agent is helpful to slow down the deterioration rate of interface treatment effect in the leaching process. The improvement effect of combined treatment methods is better than that of single treatment method.

To clarify the mechanism of water transport in mortar, a three-phase model consisting of fine aggregate-interfacial transition zone (ITZ) -cement paste was developed to represent mortar, and then the water transport process in mortar was simulated by a partial bounce-back lattice Boltzmann method (PBB-LBM). The influences of aggregate volume fraction, the ITZ’s thickness and pore structure on the water permeability of mortar were evaluated. The results show that mortar’s water permeability declines at an increased aggregate content and it is always below cement paste’s water permeability at a thin thickness of ITZ and a low porosity. Once the thickness of ITZ exceeds 150 μm or its effective porosity is two times greater than that of cement paste, the permeability of mortar is close to or even above the matrix’s water permeability. This is attributed to the competitions among the ITZ effect, aggregate dilution effect and tortuous transport path in mortar.

The hydration activity of ternesite is crucial for the development of the mechanical properties of the new Belite-ye’elimite-ternesite cement. To explore a suitable sintering procedure for improving the hydration activity of ternesite, ternesite was synthesized by different sintering procedures with analytical reagents. The effect of sintering procedure on the microstructure, crystal structure, hydration activity and mechanical properties of ternesite was investigated by scanning electron microscopy, X-ray powder diffraction with Rietveld refinement, 29Si solid-state nuclear magnetic resonance, comprehensive thermal analysis and isothermal calorimetry. The results show that ternesite grains obtained by a single-stage sintering process are irregular in shape and generally larger in size (~10 μm), while the shape of ternesite grains obtained by a two-stage sintering process are regular as granular, and the size of the grains decreases to approximately 5 μm. Air quenching can reduce the crystallinity of ternesite, thereby improving its early hydration activity and promoting the rapid development of its early mechanical properties. Among them, ternesite obtained by a single-stage sintering process and air quenching has the minimum degree of crystal structure development, but has the maximum early hydration activity and development strength. Ternesite obtained by cooling in a furnace has a higher crystallinity and a lower hydration activity in the early period, but its mechanical properties can develop rapidly in the middle and later periods.

The demand for lithium-ion batteries (LIBs) is increasing with a rapid development of new energy vehicles. Massive waste LIBs pollute the environment and have a risk of insufficient supply of lithium resources. Recycling metal lithium from waste LIBs thus becomes a recent research hotspot. Effective battery recycling can alleviate the shortage of resources and realize resource utilization, as well as reduce environmental pollution and promote the sustainable development of the industry. Also, research work on recovering lithium by preferential extraction and step-by-step separation has attracted much attentions to realize the efficient recovery of lithium metal in waste LIBs. This review represented the existing situation and methods of recycling waste LIBs, described recent research work on pyrometallurgy, hydrometallurgy, bio metallurgy and electrochemical methods in the process of selective lithium recovery, and analyzed the technical features of electrode electric field drive and membrane electrodialysis in the field of selective lithium recovery. Also, the advantages and disadvantages of each recovery process were summarized, and the problems faced by lithium recovery were analyzed in combination with economic benefits and environmental impact. In addition, the challenges and limitations of LIBs recycling were given, and the future development on LIBs recycling was prospected. This review thus provides a reference for the research and development of more energy-saving, environment-friendly and efficient recycling process of lithium metal in waste LIBs.

Ultrahigh-temperature ceramics (UHTCs) are a kind of thermal protecting material used in the extreme thermal environment due to their excellent temperature resistance. However, their intrinsic brittleness and poor thermal shock resistance restrict the engineering applications. Graphene as a two-dimensional (2D) nano-material where carbon atoms are arranged in a honeycomb structure has superior mechanical, electrical and thermal properties. It is often used as an additive phase to modify the ceramic matrix, and is considered as an ideal toughening material in ceramic composites to realize the functionalization and structuralization of composites. This review represented recent research work on the preparation process, bionic construction method, microstructure and macro properties of graphene/UHTCs. The toughening effects and mechanism, thermal properties, thermal shock resistance and oxidation resistance of UHTCs doped with graphene were discussed. In addition, some challenges and future development of this field were also put forwarded.