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Deep learning has gone through breakthroughs in many research fields including computer vision, natural language processing, etc. due to multiple driving factors such as knowledge, data, algorithms and computing power. In addition, it has gradually spawned a number of new research directions with the migration and application as well as cross-integration among various disciplines. Cheminformatics is a discipline that solves chemical problems with the applied informatics methods, and deep learning can be useful since it is very powerful in nonlinear learning. Deep learning model can be used to screen and predict in the data set, and then verify the feasibility of the results based on theoretical calculation. Finally, the results are represented by experiments, which shortens the experimental period, reduces the labor cost and accelerates the intelligence of cheminformatics. This paper briefly introduces the development history and main network model architecture of deep learning as well as the latest research and application status of deep learning in synthesis planning, compound structure-activity relation and catalyst design in recent years, and also discusses and expects the future development direction. [ABSTRACT FROM AUTHOR]

In this paper, Cu2O/CuO graphite carbon nitride adsorbent is prepared by one-step thermal polymerization with cuprous oxide and dicyandiamide as precursors. The introduction of copper oxide expands the π conjugation system of g-C3N4 effectively, which is conducive to the adsorption of dyes with benzene ring structure through π-π interaction； Cu2O/CuO-g-C3N4 adsorbent has mesoporous structures with various pore sizes, which increases its specific surface area and provides sufficient active sites for dye adsorption. The adsorption influencing factors of methyl orange, such as the preparation conditions of adsorbent, dosage, dye concentration, adsorption time, stirring speed, pH, etc., are studied. The maximal absorption ratio is 96. 11% under the optimal conditions. The kinetic analysis shows that the adsorption process is a quasi first-order kinetic model. According to the adsorption isothermal experiment, the adsorption isotherm belongs to Langmuir adsorption isotherm. In the whole adsorption experiment, the maximum equilibrium adsorption amount is 241. 25 mg/g. [ABSTRACT FROM AUTHOR]

Lithium-sulfur batteries (LSBs) have high theoretical energy density (2600 Wh/kg) and high theoretical specific capacity (1675 mA·h/g) and are regarded as one of the most promising electrochemical energy storage systems to replace lithium-ion batteries for commercial applications. However, the inherent slow redox kinetics and the “shuttle effect” of lithium polysulfides (LiPSs) seriously affect cycle performances of LSBs. At present, most of the reviews focus on the design of sulfur host materials for LSBs under excess electrolyte, researches on improvement of battery performances under lean electrolyte are less. Herein, this paper introduces the regulation of different electrocatalysts on the redox reaction kinetics of LSBs under lean electrolytes. It is mainly divided into two categories: non-metallic catalysts (non-metallic compounds, graphene, carbon nanotubes and heteroatom doped carbon materials) and metal catalysts (cobalt-based, molybdenum-based, iron-based and multi-metal-based heterogeneous structures). Finally, further researches are proposed and prospected to promote the commercial application of LSBs. [ABSTRACT FROM AUTHOR]

As an emerging material, multifunctional metal-organic framework MIL-88A (Fe) poses a potential application in water treatment. Considering the unique physical and chemical properties of MIL-88A (Fe) (i. e. porous structure, unsaturated metal sites and excellent visible light absorption ability), MIL-88A (Fe) can heterogeneously combine with other functional materials (i. e. carbon materials, inorganic semiconductor materials) to improve its adsorption and catalytic performance. This paper reviews the application of MIL-88A (Fe) and its composites as adsorbents and catalysts in water treatment. The mechanism of adsorption removal of pollutants in water by MIL-88A (Fe) and its composites (especially heavy metal ions) is summarized, and the reaction mechanism for degradation of organic pollutants in water by MIL-88A (Fe) and its composites in photocatalytic technology, Fenton-like technology, peroxydisulfate advanced oxidation technology and ozone-catalytic technology is introduced. It is pointed out that the MIL-88A (Fe) -based functional materials have problems such as narrow applicable pH range and difficulty in recycling in the process of wastewater treatment. Future research needs to optimize the preparation condition of MIL-88A (Fe) to improve the yield and ensure the regular morphology, small size and high crystallinity of MIL-88A (Fe), improve the stability of MIL-88A (Fe) by surface coating technology, and enhance the recycling performance of MIL-88A (Fe) by endowing its magnetic property. In addition, according to the structure of the target organic pollutants and water quality condition, it is necessary to reasonably adjust the degradation contribution of the free radical pathway and the non-radical pathway to the target pollutant in the MIL-88A (Fe) -based advanced oxidation process, thus achieving the best decontamination effect. [ABSTRACT FROM AUTHOR]

Uranium is an efficient and clean fuel for nuclear energy， but it inevitably produces uranium containing wastewater in the nuclear industry. If it is not treated in time and leaked into the environment， it will pose a threat to the health of animals， plants and human beings. Therefore， the separation process of U (Ⅵ) in aqueous solution is urgent based on the perspective of energy recovery and environmental protection. Adsorption techniques have especially attracted attentions because of their advantages on feasibility， efficiency and simple operation. As an ideal adsorbent， functionalized mesoporous silica material has the advantages of large specific surface area， high pore capacity and adsorption capacity. It has a wide range of applications in the field of adsorption and separation for uranium. In this paper， the characterization and adsorption mechanism of U (Ⅵ) adsorption in aqueous solutions at home and abroad are reviewed on the basis of functionalized mesoporous silica preparation methods， combined with X-ray photoelectron spectroscopy， Fourier transform infrared spectroscopy， X-ray absorption fine structure spectroscopy， X-ray energy spectrum analysis and Raman spectroscopy. Although there have been encouraging and potential developments in functionalized mesoporous silica adsorbed uranium， the design and mass production of novel multifunctional adsorbents for applications in actual environments remain challenging. [ABSTRACT FROM AUTHOR]

Molecular imprinting technology（MIT） has predetermination, recognition and usability, and has been widely used in chromatographic separation， solid phase extraction, drug analysis, chiral recognition and other fields. In recent years， researchers have introduced macrocyclic compounds into MIT， which not only increases the types of functional monomers， but also effectively improves the specificity of molecularly imprinted polymers and the selectivity of target molecules. In this paper， the research progress and application of macrocyclic compounds such as cyclodextrin， calixarene， pillararene， crown ether, cucurbituril and other supramolecular compounds in MIT in the past ten years are reviewed and its development prospects are prospected. [ABSTRACT FROM AUTHOR]

In this paper, five compounds（D1-D5） are successfully synthesized from 3,5-diamino-1,2,4-triazole and substituted benzaldehyde. The in vitro antifungal activities of the compounds against Fusarium graminearum are studied by the mycelial growth rate method and molecular docking technology. The results show that, except for compound D3, the activities of the others are superior to that of the control drug fluconazole, and the inhibitory effect of compound D1 is about 1. 8 times than that of the control drug, which could be used as the lead compound against Fusarium graminearum. The results of molecular docking are consistent with the biological activity, that is, the lower the docking binding energy, the stronger the activity against Fusarium graminearum, and hydrogen bonding is the key factor to maintain the stable binding between the drug molecule and the receptor protein. In order to overcome the drug resistance of pathogenic bacteria, the antibacterial effect of the most active compounds D1 and D2 with the fluconazole combined system are investigated, and the results exhibit that co-toxicity coefficient（CTC） values are greater than 120, which shows the synergistic effect when the mass ratio of compound D1 and fluconazole is 1∶2, D2 and fluconazole is 1∶1, 1∶1, 1∶2, 1∶4 and 4∶1, so compound D2 is expected to be a promising compound dispensing agent. [ABSTRACT FROM AUTHOR]

Ginseng，American ginseng and notoginseng are closely related species of Panax genus. They have similar morphologies and chemical compositions. These three species all have the characteristics of continuous cropping obstacle. After continuous cropping of Panax，the soil environment gradually becomes unsuitable for its growth and the plant growth becomes weak and susceptible to disease，leading to inhibited growth, serious root rot, fibrous root loss, and even plant death. One of the main reasons for the continuous cropping obstacles of Panax genus is allelopathic autotoxicity. The residue degradation product of Panax genus is one of the main sources of ginseng allelochemicals. It can reduce the germination rate of seeds, increased mortality of seedlings, aggravates diseases such as root rot and eventually cause continuous cropping obstacles. During the continuous crop of Panax genus, the soil is also directly or indirectly affected by changes in soil physicochemical properties through the exchange of allelochemicals with the soil. In this paper, the research progress of decomposed allelopathy of Panax genus and the effect of decomposition on soil components are reviewed. It provides references for decomposed allelopathy of Panax genus and soil utilization research. [ABSTRACT FROM AUTHOR]

Ammonia synthesis in the traditional Haber-Bosch process requires large energy consumption and complex plant infrastructure. Driven by the development of renewable energy, electrocatalysts for the nitrogen reduction reaction（NRR） have attracted ever-growing attention and have been considered as the most efficient alternative to the catalyst in the Haber-Bosch process. However, this process suffers from low NH3 production and Faradaic efficiency. Therefore, the development of more efficient electrocatalysts is crucial for their practical applications. Among the previously reported catalysts, single-atom catalysts（SACs） exhibit significant advantages in efficient utilization of atoms and unsaturated coordination, providing a huge scope for optimizing catalyst performance. In this paper, the theoretical research of single-atom catalysts in electrochemical ammonia synthesis is reviewed, and the performance of three types of single-atom catalysts, namely noble metal catalysts, non-precious metal catalysts and metal-free catalysts, is analyzed in detail, aiming to provide new ideas for the development of electrochemical ammonia synthesis technology. [ABSTRACT FROM AUTHOR]

The unique black soil resources and natural environment of Jilin province provide the proper conditions for the growth of ginseng-the king of herb. Ginseng industry has effectively promoted the development of medical and health industry, and brought considerable economic income for ginseng farmers. However, long-term continuous cropping of ginseng causes the chemical, biological, and physical properties deterioration of soil, which influences the yield and the quanlity of ginseng, and results in the occurrence of replant obstacle. Identifying the malignant soil factors in continuous cropping obstacles, then analyzing the evolution process, and putting forward the improvement strategies is the primary task of ginseng research at present. This paper reviews the influence of ginseng cultivation on the physicochemical property, nutrient, enzyme activity, microecology and ecotoxicity of the soil, and the achievements of improving ginseng soil by chemical and biological techniques and methods in recent 10 years. [ABSTRACT FROM AUTHOR]

Recently, the use of computational methods such as Molecular Dynamics (MD)simulations and Hansen Solubility Parameters (HSPs)to study the behavior of small molecule gelators has attracted much attention. MD simulation is a computational method based on classical mechanics and is one of the preferred techniques for understanding the process of small molecule gelators. The MD simulation can more accurately analyze the gelation trend or assembly behavior of small molecule gelators, dynamically and graphically display the self-assembly process, effectively reveal the relationship between the structure of small molecule gelators and related gelation behavior, and quantitatively analyze non-covalent bond interactions such as hydrogen bonds, π-π stacking, van der Waals interactions, ionic bonding and solvophobic interactions. By performing molecular dynamics simulations on known gelators/non-gelators, parameters related to gelation behavior in the simulated data are extracted, and the linear correlation is measured by fitting the Pearson correlation coefficient to finally predict the gelation behavior of a certain class of small molecules. On the other hand, the empirical model developed according to the HSPs is the most representative, which consists of the energy of dispersion interaction (δd), the energy of polar interaction (δp)and H-bonding energy (δh)between molecules. These three parts determine the coordinate point of the three-dimensional space (Hansen space). According to the range of the point, it can be determined whether the organic small molecule can form a gel in a specific solvent. In this paper, representative works published recently in the field of organic small molecule gels by using MD simulations and empirical models are reviewed. Some comments on the assembly behavior of gelators, the regulation and prediction of non-covalent bond interactions on gelation ability are made. [ABSTRACT FROM AUTHOR]

Fuel cell is a new type of energy conversion device using hydrogen，methanol，etc. as fuel，among which the proton exchange membrane fuel cell（PEMFC）has been widely used in mobile power，submarines and electric vehicles by virtue of its high energy power，fast start-up speed and long service life. Proton exchange membranes（PEM）have the greatest impact on the performance of PEMFC. Efficient PEMFC requires PEM with high proton conductivity，good thermal stability and mechanical properties，low fuel permeability and excellent physical and chemical stability. Most of the membranes currently used in the market are Nafion membranes with excellent proton conductivity，but they have disadvantages such as difficulty in preparation， expensive cost，and heavy dependence on humidity for proton conductivity，which limits their development to some extent. In order to make more options for proton exchange membranes，scientists have been focusing on using new materials to replace Nafion membranes. In recent years，scientists have simulated the Nafion structure by synthesizing various side chain polyaryl ether structures containing sulfonic acid groups，allowing the formation of microphase separation structures between hydrophilic sulfonic acid groups and hydrophobic groups，resulting in a series of proton exchange membranes with excellent overall performance. This paper focuses on the synthesis methods and properties of several common strategies，such as side chain alkyl sulfonated type，side chain sulfonated block type，side chain partially dense sulfonated type，side chain sulfonated cross-linked type and side chain sulfonated composite type. Finally，the advantages and development prospects of side chain sulfonated polyaryl ethers in the field of proton exchange membranes are reviewed. [ABSTRACT FROM AUTHOR]

Rice starch particles have small and uniform particle size, good dispersibility in water and film-forming property, and can be degraded in nature. At present, starch is widely used in food packaging, medical dressings and cosmetics industries. Using rice starch as raw material, sodium hydroxide as paste, glycerol as plasticizer and citric acid as crosslinking agent and solution pH regulator, starch film was prepared by tape casting. By measuring the morphology of starch particles, the gelatinization conditions of starch particles, gelatinization temperature, apparent viscosity and pH value of starch solution, mechanical properties, light transmittance and potassium glycyrrhizinate release performance of starch film tostudy the gelatinization conditions of rice starch, the effects of mass fractions of citric acid, starch and glycerol on the properties of starch film and the release of carrier substances. The results show that the rice starch used in this paperexists in the state of dispersed particles, and the gelatinization temperature ranges from 82. 5 to 100. 8 ℃. Citric acid interacts with starch molecules in the process of starch film formation, and can adjust the pH value of the solution to adapt to human skin. When the concentration of starch in the starch film becomes higher, the hardness after film formation is greater. The higher the concentration of glycerol, the better the elongation at break of starch film and the worse the tensile strength. In addition, the transmittance of starch film is the best when the concentration is 3. 0%, which with good light transmittance has low crystallinity. Finally, the starch film prepared in this paper can contain the effective substance dipotassium glycyrrhizinate, which can be used as a skin repair film in cosmetics. [ABSTRACT FROM AUTHOR]

In order to improve the utilization ratio of pesticides and reduce the harm of pesticides to the environment， nano loss control chlorpyrifos (NLCC) is fabricated by loading chlorpyrifos (CPF) on attapulgite(ATP). The loss control effect of ATP on CPF is studied by filter paper and sugarcane leaves and the interaction of NLCC system is studied by SEM，FT-IR，XRD，and so on. Furthermore，the loss control effect of ATP on CPF is also investigated by field test. These results show that ATP could adsorb CPF by hydrogen bonds and the adhesion amount of CPF before and after rainfall increases by 5. 4 μg and 5. 6 μg， respectively. The maximum loading amount of attapulgite to chlorpyrifos is 500 mg/g. In addition，the mortality of corn borers increases by 20% respectively. Moreover，the field test also shows that NLCC could reduce 21% of sugarcane damaged by pests，4. 3% of sugarcane stalks damaged by pests，and the wormholes of 2 per plant and increase the height by 23. 1 cm. These results indicate that NLCC could effectively reduce pests and promote the growth of sugarcane. Therefore，this study provides a simple and practical method for reducing pesticide loss，improving pesticide utilization rate，and decreasing environmental pollution，which has a high application value for the development of green agriculture. [ABSTRACT FROM AUTHOR]

As an economic crop, ginseng has been planted in China for thousands of years. Because of its various pharmacological activities, ginseng is widely used in food, medicine, cosmetics and other fields, but the actual output of ginseng can't meet the market demand at present. Improving the production efficiency of ginseng is still the primary objective of ginseng planting research. In recent years, many new modes, technologies, methods and instruments have emerged in the production, such as site election, seed treatment, sowing, scaffolding, cultivation and harvesting. This paper summarizes the research status of ginseng cultivation from cultivation mode and techniques, hoping to provide reference for improving the production efficiency of ginseng. [ABSTRACT FROM AUTHOR]

In this paper, Fe/V doped cubic Sb2O3 crystalline composites are successfully prepared by chemical deposition and roasting methods. The samples are characterized by using infrared spectroscopy and ultraviolet spectrophotometry, and elemental composition and characteristics are also analyzed by X-ray diffraction and X-ray photoelectron spectroscopy. The mechanism of photo-degradation of pharmaceutical wastewater TC is studied by the addition of inhibitors. Spectral characterization shows that the light absorption of the Fe/V doped cubic Sb2O3 crystalline composites with the sulfuric acid dipping gradually extends from ultraviolet region to visible region, in which, the absorption peak of the impregnation concentration of 4 mol/L H2SO4 is the strongest. The photocatalytic degradation rate of TC can reach 99. 3% by using optimized composites as the photocatalyst with the reaction time of 180 min. It also performs the smallest band gap value for 2. 15 eV, the maximum photocurrent value（0. 79 mA）and the smallest AC impedance value (355 Ω). The results of capture experiment and the analysis of catalytic mechanism are consistent that the hydroxyl radical produced during photodegradation plays a leading role. [ABSTRACT FROM AUTHOR]

The low-k dielectric materials with their low mechanical strength and high porosity for advanced IC processes pose great challenges in barrier CMP slurries, requiring favorable advantages in high removal rate, adjustability, lower surface defects and improved edge over erosion (EOE). In this paper, the effects of polyether amines on the removal rate and defects toward low-k materials are studied. The results show that the removal rate of low-k material decreases by 68%~85%, the number of residual particles on the surface of low-k material decreases by 80%, and EOE decreases by 2/3, which meets the requirements of advanced technology for barrier CMP slurries. [ABSTRACT FROM AUTHOR]

The specific interaction between receptor and ligand on cell surface plays an important role in cell biology. However, the distribution of receptor molecules on the cell membrane is discontinuous and dynamically different from that in the homogeneous solutions. The receptor-ligand interactions on the cell surface usually exhibit complex nonlinear binding patterns. In order to reveal the mechanisms, framework nucleic acids, as a class of DNA nanostructures with definite geometric shapes, could be used for the coupling of multivalent ligands. With the addressability at nanoscale, the number, spacing and spatial conformation of ligands are precisely regulated on framework nucleic acids. The binding characteristics between receptor and ligand on cell surface are studied, and efficient molecular recognition and targeted therapy could be achieved by optimizing these influencing factors. In this paper, the research progress of receptor-ligand interactions on cell surface based on framework nucleic acids is reviewed. By discussing the important influencing factors and biological applications, the future development of receptor-ligand interactions on cell surface based on framework nucleic acids is prospected. [ABSTRACT FROM AUTHOR]

Covalent organic framework materials（COFs）are a new type of crystalline porous materials，and their chiral materials have good application prospects in various fields. In this paper，TpBD（NH2 ）2 synthesized by the reaction of 1，3，5-trialdehyde phloroglucinol（Tp）and 3，3´-dinitrobenzidine（BD）was used as the covalent organic skeleton，and reacts with（1S）-（+）-10-camphorsulfonyl chloride（Cam）to prepare（1S）-（+）-10-camphorsulfonyl chloride derivative TpBD-1S-（+）-Cam. The derivative is a newly synthesized chiral covalent organic framework material. TpBD-1S-（+）-Cam was immobilized on silica gel to prepare a chiral column for high performance liquid chromatography to separate racemates. The experimental results show that the prepared COF，TpBD-1S-（+）-Cam，can separate warfarin，chlorpheniramine maleate， atenolol，metoprolol，zopiclone，10-（9-anthryl）-2，2，2-trifluoroethanol，1，2-benzophenone，ketoprofen， mexiletine hydrochloride，timolol 10 kinds of racemates and o，m，p-bromoaniline，o，m，p-iodoaniline are two kinds of positional isomers of benzene series. This material has potential as the stationary phase of high performance liquid chromatography. [ABSTRACT FROM AUTHOR]

As the third generation of new concept solar cells，perovskite solar cells have the advantages of high photoelectric conversion efficiency，low-cost and flexible processing. They have been developed rapidly in recent years. Their photoelectric conversion efficiency has increased from 3. 8% at the beginning to 25. 5% in the near future. They are gradually comparable to silicon cells and have been close to the level of commercial application. At present，the key link to realize the industrial application of perovskite solar cells is battery packaging. It can not only solve the stability problem of perovskite photovoltaic devices，but also meet the requirements of battery safety，environmental protection and prolonging service life. Combined with the development status of perovskite photovoltaic cell packaging materials and packaging technology in recent ten years，this paper introduces the achievements and shortcomings in the field of perovskite cell packaging， and discusses the advantages and disadvantages of the existing packaging technologies，as well as their applicable different device types. Under different temperature and humidity conditions，the effects of different packaging material properties and packaging process conditions on the efficiency and stability of perovskite battery are compared，and three key factors affecting the packaging effect of perovskite battery thin film are summarized：elastic modulus of polymer，water vapor transmittance and processing temperature. The suitable processing temperature，advantages and disadvantages and processing cost of different polymer film packaging materials are compared. It can be seen that with the strong growth of industrial demand for perovskite photovoltaic cells and the deepening of people's research on their packaging materials，it will be an inevitable trend to study new functional polymer packaging materials suitable for large-scale production and photovoltaic building integration. [ABSTRACT FROM AUTHOR]

Under an external voltage，the optical properties（e. g. color，transmittance，etc.）of electrochromic materials can controllably and reversibly be changed，which has an important application prospects in the fields of energy conservation and emission reduction. With the continuous innovation and development of related research，the single-component electrochromic materials cannot show the expected electrochromic properties due to the limitations of their own structure and performance，and cannot be designed and regulated in their structure and performance，so it is increasingly unable to meet the needs of practical applications. Comparing with the non-composite electrochromic materials，the composite materials have obvious advantages in this aspect. Through the reasonable material design and with the coordination of each component，the core competitiveness of the composite materials is mainly represented by the electrochromic materials with excellent structure and performance can be obtained by stimulating the advantages and overcoming the disadvantages of each component. Therefore，more and more research focus on the composite electrochromic materials in recent years. At present many kinds of composite electrochromic materials have been researched，which mainly can be divided into three categories as inorganic-inorganic composite，organic-inorganic composite and organic-organic composite according to whether the composite components are inorganic or organic materials. Compared with the organic electrochromic materials，the inorganic electrochromic materials have significant advantages in material composition control，mechanical properties，optical modulation，service stability，life and other aspects. Therefore，either the single-component or the composite inorganic electrochromic materials have always been an important direction of research in this field. Hence，this paper devotes to the research status and development tendency of the inorganic-inorganic composite electrochromic materials，devices and electrolytes，including the research progress，the existing problems and the development trend. It will provide a basis for the further development and application of composite electrochromic materials. [ABSTRACT FROM AUTHOR]

Posaconazole， as the second generation of triazole antifungal drugs， has a wide antifungal spectrum and strong antibacterial activity. It is widely used in clinical practice. However， it has been eight years since its publication before it is approved in China. In order to better understand posaconazole， a first-line drug with great clinical demand， this paper summarizes the pharmacokinetics， pharmacological properties， clinical application and synthetic route of posaconazole in the literature at home and abroad. It is hoped that it can fill the gap in the domestic API market， break the current situation that the API is completely dependent on import， and provide a useful reference for the industrial R ＆ D. [ABSTRACT FROM AUTHOR]

Some short peptides can spontaneously self-assemble into various nanostructures via the synergistic driving forces of non-covalent interactions. These non-covalent interactions，including electrostatic interaction，hydrogen bonding，aromatic interactions and other non-covalent interactions，are usually highly coupled together. Through rational sequence design and proper modification of short peptide molecules，the driving forces could be regulated purposively，and the nanostructures and morphologies of the self-assemblies could be controlled accordingly，and thus so as to achieve the fabrication of peptide-based supramolecular biomaterials and develop their functions. In this paper，the effects of hydrogen bonding，π - π stacking， electrostatic interaction，hydrophobic interaction，metal ion coordination and chiral center on the selfassembly behavior of peptide self-assembly have been reviewed. The driving force regulation strategies， including sequence design，pH and concentration adjustment and metal ion coordination，and the resulted nanostructures have also been discussed. We also make the outlooks on the development of peptide-based supramolecular biomaterials with specific functions in biomedicines and biocatalysis. [ABSTRACT FROM AUTHOR]

Two kinds of thermoplastic polyurethanes （TPUs） with the same molecular composition and different hardness are used to prepare TPU blends with different hardness. The relationship betweenthe hardness and impact properties of TPU blends is investigated.The impact properties of TPU blends are characterized by the falling ball impact test， pressuresensitive paper test and sample surface temperature test before and after impact. When the hardness of the sample is lower， the peak impact force is smaller， the impact duration is longer， the maximum strain of the sample is larger， the maximum impact area of the sample increases， and the value of maximum stress decreases. The energy dissipation ratio of samples with different hardness has little difference， but it shows a trend of slight increase with the decrease of hardness. The surface temperature of samples after impact increases compared with that before impact， indicating that part of energy is dissipated by heat. The temperature difference of samples with different hardness is similar， which is similar to the change of energy dissipation ratio of samples. All samples have high energy dissipation ratios. TPU can dissipate most of the impact energy， and has good impact resistance. [ABSTRACT FROM AUTHOR]

Based on the phenomenon that rhodamine derivatives（4-N-acrylamide-（3'，6'-bis（diethylamino）- spiro［isobenzofuran-1，9'-xanthene］-3-one）（AM-RhB）will open the lactone ring to display color or emit fluorescence under moderate acidic conditions（4. 425%） and fluorescence intensity modulation （>700） before and after stimulating with water ，and good reversibility （> 5 times）. This work will provide a promising way for the development of new hydrochromic materials. [ABSTRACT FROM AUTHOR]

Heavy metal ions have caused serious harm to the ecological environment and human health. It is urgent to treat heavy metal ions in water. In this paper，a co-precipitation method was used to prepare ethyl cellulose magnetic composite material（EC/Fe3O4）by using ethyl cellulose as a template to compound Fe3O4 nanoparticles with ethyl cellulose. The influence of the adsorption dosage，pH value of the solution， adsorption time and other factors on the adsorption process of Cu（II）in the solution was explored. The results show that EC/Fe3O4 exhibits good adsorption rate and adsorption performance. The adsorption equilibrium can be reached within 4 min. Under the adsorption conditions of Cu（II）concentration of 20 mg/L，solution pH of 7，and adsorption time of 160 min，the unit adsorption qe of EC/Fe3O4 is 76. 98 mg/g，and the maximum removal rate is 94. 68%. After 8 adsorption cycles，the unit adsorption capacity is 62. 21 mg/g. [ABSTRACT FROM AUTHOR]

Lead is a toxic heavy metal which is widely distributed in nature and affects the ecological environment and human health. Therefore，it is of significance to detect lead ions in the environment. In this paper，a modified glassy carbon electrode is fabricated by Ce2Zr2O7. 04 nanocomposites that are prepared by the hydrothermal method. Scanning electron microscope （SEM）， X-ray diffractometer （XRD） and X-ray photoelectron spectroscopy（XPS）are used to characterize the composition，morphology and valence state of the as prepared materials. Square wave anodic stripping voltammetry（SWASV）is applied to detect Pb2+，and it is found that the modified electrode has a good current response to Pb2+ . Meanwhile，the examined conditions such as buffer solution，deoxidization time，enrichment potential and pH are optimized. The results show that the linear range of Pb2+ is 0. 0025~3. 5 μmol/L，the detection limit（LOD）（3S/N） is 0. 198 nmol/L，and the recovery rate is between 97. 6% and 104. 4% under the optimized test conditions. The method used in the determination of Pb2+ in water samples manifests good reproducibility，stability and antiinterference ability，which provides a new method for the detection of Pb2+ in water samples. [ABSTRACT FROM AUTHOR]

As a substitute for inorganic glass, organic optical resin has the advantages of light mass, good impact resistance, easy processing, and strong adjustability. The refractive index is one of the main parameters of optical resins. The level of refractive index can directly affect the thickness, aesthetics and comfort of the finished lens. Improving the refractive index of optical resins without reducing the overall performance of optical resins has always been a hot and difficult point in this field. The introduction of sulfur with high molar refractive index into optical resins is considered to be one of the most effective and commonly used methods. In this paper, sulfur-containing optical resins are divided into olefins, epoxys, episulfides, sulfur heterocyclic rings, and polyurethanes. The research progress in recent years at home and abroad is briefly reviewed, involving monomer synthesis, monomer polymerization, and the influences of monomer structures on the comprehensive performances of optical resins. The properties and development of the above materials are also analyzed. [ABSTRACT FROM AUTHOR]

Carbon quantum dots (CQDs) are a category of semiconductor-like nano-materials with small particle sizes, significant photo properties and outstanding charge transportation properties, and have been extensively utilized in the modulation and amelioration for the photovoltaic performance of perovskite solar cells (PSCs). Herein, on the basis of syntheses, properties and applications of CQDs, this paper mainly reviews the recent progress on the utilization of CQDs in the electron transportation layer (ETL), perovskite light absorbent layer, hole transportation layer (HTL) of PSCs. Finally, the future development trend of perovskite solar device performance modulation with these CQDs materials is also prospected. [ABSTRACT FROM AUTHOR]

DNA denaturation by thermal melting is critical for DNA amplification and detection. However, the uneven heat distribution and temperature change hinders its application in DNA amplification and detection. It's highly desired to explore a fast and efficient approach to regulating DNA degeneration. In this paper, we propose to apply acid, instead of thermal melting, to accelerate the DNA denaturation by regulating DNA conformation quickly and precisely via protonation of cytosine. We find that the thermodynamic properties of DNA highly depend on its molecular conformation. Furthermore, compared with traditional thermal method, pH method significantly increases the rate of DNA denaturation by more than 6 times. We further found that the mechanism of the pH control method to improve DNA denaturation by rapidly decreasing the enthalpy of double-stranded DNA (160 kJ/mol), and hope that this method can be used in applications of DNA amplification and detection. [ABSTRACT FROM AUTHOR]

Photocatalytic nano-TiO2 is favored for its excellent photocatalysis, chemical stability and broadspectrum antibacterial properties. However, some problems, such as wide gap, high overpotential and fast recombination of photocarriers, limit its photocatalytic performance. This paper reviews the recent progress of TiO2 photocatalysis in antibacterial research. The mechanism of photocatalytic antibacterial activity of nano- TiO2 is discussed, and several strategies to improve the photocatalytic antibacterial activity of nano-TiO2 are discussed, including the structural design of nano-TiO2, the regulation of light, the doping of metal ions, the doping of non-metal ions, the modification of precious metals and the coupling of other materials. The modified TiO2 photocatalyst inhibits the growth of bacterial cells significantly, which has a unique application prospect in biomedical engineering. [ABSTRACT FROM AUTHOR]

In this paper, the effects of three different anodic materials (copper wire, galvanized steel and nickel wire) on the structure and morphology of carbon materials prepared by electrochemical reduction of CO2 in molten salt were studied. Three carbon structures, e. g., hollow quadrilateral carbon (HQC, the product with Cu as an anode), carbon nanosheet (CNS, the product with galvanized steel as an anode) and sponge porous carbon (SPC, the product with Ni as an anode), were prepared, and their electrocatalytic properties towards the two-electron oxygen reduction reaction (2e− ORR) were explored. The results show that the CNS prepared by using galvanized steel as the anode material is composed of a large number of carbon nanosheets, in which there are abundant pore structure defects. Compared with HQC and SPC, CNS shows the highest 2e− ORR electrocatalytic activity and H2O2 selectivity (close to 90%. The high activity and selectivity of CNS are attributed to its high ID/IG (ID/IG is the ratio of the intensity of D peak and G peak in Raman spectrum, and its ratio reflects the defective degree of the material） value and high C—O/C==O ratio, indicating that structural defects and C—O/C==O functional groups are crucial to the catalytic performance of CNS. In addition, CNS exhibits excellent electrocatalytic stability, and the ring current almost does not decay after 14 hours potentiostatic test. The use of CO2 as the carbon source to synthesize electrocatalytic carbon materials not only can be used as a potential option to mitigate the greenhouse effect, but also provide a new idea for the practical application of CO2 derived carbons. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) is a key reaction in electrochemical systems such as metal-air batteries and hydrogen production by electrolysis of water. Research on high-efficiency and stable nonprecious metal electrocatalysts is very important. In this paper, nickel-cobalt bimetallic phosphides (NiCo-P) with multi-shell hollow structures were prepared by high-temperature calcination with metal-organic framework (MOF) as precursors. The unique structure is conducive to the penetration of the electrolyte and mass transfer, and can provide a wealth of exposed active sites. At the same time, the nickel-cobalt bimetal has a synergistic effect to promote electrochemical performance. The results show that the NiCo-P-0. 1 catalyst prepared with a molar ratio of nickel to cobalt of 0. 1 exhibits good catalytic activity and stability in 1. 0 mol/L KOH electrolyte, which has good application prospects. This work provides a brand new approach for the development of electrocatalytic oxygen evolution catalysts with highly activity and stability. [ABSTRACT FROM AUTHOR]

Lithium-sulfur (Li-S) batteries are one of the promising next-generation energy storage technologies due to their high theoretical specific capacity and energy density. However, in practical applications, low conductivity of sulfur and lithium sulfide, dissolution of polysulfides (LIPSs), and poor conversion of LIPSs to Li2S2/Li2S result in the short lifespan and low rate performance of Li-S batteries. Recent studies show that single-atoms (SAs) with superior catalytic activities are ideal anchoring centers and catalytic sites for LIPSs. Modification of cathodes and separators with SAs helps to adsorb polysulfide, improve reaction kinetics and inhibit the shuttle effect. In addition, introduction of SAs into the anode can significantly improve the reversibility of Li deposition/stripping and inhibit the growth of dendrites. In this paper, we review the research progress of SAs in lithium-sulfur batteries, including material synthesis, characterization methods, application direction and catalytic mechanism. Finally, the key challenges and future developmental trends of SAs are summarized and discussed. [ABSTRACT FROM AUTHOR]

The effect of alkali/alkaline earth metals (AAEM) on biomass pyrolysis and the composition of pyrolysis products can provide important theoretical basis for the study of biomass pyrolysis characteristics and the efficient utilization of pyrolysis products. In this paper, pine sawdust was used as pyrolysis raw materials, and the acid washed sample was soaked with potassium, calcium, sodium and magnesium chloride solution, respectively. The samples were rapidly pyrolyzed at 500℃under Ar atmosphere. The influence of four metal ions on the composition and distribution of pine sawdust pyrolysis products was investigated. The pyrolysis characteristics of each sample were investigated by thermo-gravimetric analysis. The tar components of the fast pyrolysis were investigated by gas chromatography/mass spectrometry (GC/MS). The results show that: AAEM has obvious catalytic effect on pine sawdust, the existence of AAEM ions can improve the yield of pyrolysis gas and solid, reduce the yield of tar; AAEM can reduce the pyrolysis temperature and make the pyrolysis easier; the tar components of fast pyrolysis mainly include phenols, ketones, aldehydes, aromatics, alcohols, dehydrated sugars, furans, acids and AAEM will cause changes in the relative contents of these substances, especially furans and aromatics. These experimental results provide an important reference for optimizing the pyrolysis conditions of biomass and improving the quality of pyrolysis bio-oil. [ABSTRACT FROM AUTHOR]

Crystallization of poly (1-butene) (PB) can be manipulated by addition of isotactic polypropylene (PP), and therefore PB/PP blends have attracted considerable attention. Despite many studies on this system in the literature, the miscibility of the two components remains a controversy. In the present paper, we investigated the compositions of the micro phases in PB/PP blends by atomic force microscopy-infrared (AFM-IR). A Fourier transform infrared (FT-IR) quantitative analysis method was first established to determine the PB content in a PB/PP blend based on the peak area ratio of the 1460 cm-1band to the 1378 cm-1band, and then taking advantage of the consistency between the AFM-IR and the FT-IR spectra, the calibration was applied to extract the micro phase composition from the AFM-IR spectra acquired for the micro phases. It is found that a PB/PP blend containing 70% mass fraction of PB phase separates into a PB-rich phase and a PP-rich one, with PB mass fractions of 78% and 19%, respectively, indicating that the two components are partially miscible to one another. [ABSTRACT FROM AUTHOR]

Excessive emission of sulfur dioxide (SO2) poses a serious threat to the natural environment, making the capture and utilization of SO2 widely concerned in industrial production. Currently, technologies of capturing SO2 have been relatively mature, and the value-added utilization of the captured SO2 has become a hot-point issue. Among various SO2 utilization technologies, chemical utilization is considered to be one of the most promising methods for realizing value-addition of SO2 because of the advantages of excellent atomic economy and low energy consumption. In this paper, the oxidation and reduction of SO2 and organic synthesis using SO2 in inorganic and organic reactions are reviewed. The reaction mechanism and reaction conditions of conversion of SO2, and the influence of different catalysts on the reactions are introduced. The challenges of severe reaction conditions and high dependence on catalysts in chemical utilization of SO2 are pointed out. The further research directions of chemical utilization of SO2 are prospected. [ABSTRACT FROM AUTHOR]