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The Li+ adsorption and separation from low concentration solution by lithium-ion sieve has become one of the most promising methods due to the high selectivity, adsorption capacity and adsorption rate towards lithium ion (Li+). However, the industrial application of lithium manganese oxide ion-sieve is limited due to its difficult recovery, high Mn dissolution loss rate and poor circulation performance. In this paper, the spinel-structure chromium-iron composite doped lithium-ion sieves were prepared by high-temperature solid state reaction method using LiOH·H2O, MnO2, Fe2O3, and Cr2O3 as raw materials. The effects of Cr doping amounts and calcination temperature on the phase structure, adsorption performance, and Mn dissolution loss rate of the lithium-ion sieve precursors were investigated. The results showed that the adsorption capacity of the synthesized lithium-ion sieve could reach 27.30 mg/g and the Mn dissolution loss rate was only 0.43% when the molar ratio of Li, Mn, Fe and Cr was 1∶2∶0.05∶0.05 and the calcination temperature was 550 °C. The selection adsorption experiments showed that the lithium-ion sieve presents excellent selection performance for Li+. Furthermore, the recycling performance of chromium-iron doped lithium-ion sieve showed that the adsorption capacity could still remain 89% of the second cycle (18.51 mg/g) after five cycles, which is greater than 56% of the undoped lithium-ion sieve. [ABSTRACT FROM AUTHOR]

Amorphous alloys have attracted much attention in the field of high-speed motors because of their excellent comprehensive soft magnetic properties, especially their extremely low loss at high frequencies. In this paper, the advantages and types of amorphous motor are summarized, the key preparation processes of amorphous stator core are reviewed, and the advantages and disadvantages of radially laminated and axially wound core, modular splicing and integral forming core, slotted and slotless core are compared. The effects of the above-mentioned preparation processes on the properties of amorphous strip and iron core are summarized from the perspectives of annealing treatment, dipping curing and processing forming methods. Finally, combining with the latest research progress of amorphous motor, the problems existing in the application of amorphous alloy to the stator core of amorphous motor are analyzed, and the development of machining methods for amorphous motor stator core in the future is prospected. [ABSTRACT FROM AUTHOR]

As a new type of non-metallic polymer semiconductor, graphite phase carbon nitride (g-C3N4) has the properties of easy synthesis, non-toxic and harmless, acid and alkali corrosion resistance, and good environmental affinity. The unique layered structure gives it a high specific surface area, and the moderate band gap width gives it better photocatalytic performance. However, pure phase g-C3N4 has the disadvantages of small specific surface area, insufficient active site, rapid carrier recombination and weak redox ability, which restrict its effective application in the field of photocatalysis. Studies have shown that the structural regulation of g-C3N4 using a template induction process can effectively solve the above problems. In this paper, the template methods commonly used for the preparation of graphite phase carbon nitride (hard template method, soft template method and biological template method) are reviewed, the progress of multiphase composite process is discussed, and the application of g-C3N4 based materials in photocatalytic degradation, CO2 conversion and hydrogen produc- tion are summarized. [ABSTRACT FROM AUTHOR]

Carbon based materials are currently the most commonly used electrode materials for lithium-ion batteries, although significant capacity loss in carbon based lithium-ion batteries (LIBs) is caused by low temperature. In this paper, porous carbon was prepared from rice husks through high-temperature carbonization. Porosity provides more transport pathways and active sites for Li+, as well as promotes the transport and diffusion. The results indicated that carbonization temperatures have an impact on the microstructure of rice husk derived active carbon (RHC), and the performance of batteries constructed based on various RHC electrodes was different. The RHC-10 negative electrode obtained at 1000 °C has the highest residual reversible specific capacity, reaching 230 mA/g at 0.2 C magnification and 147 mAh/g at 2 C magnification after 100 cycles, respectively. After 10 cycles at different magnification, the highest reversible specific capacity can still be maintained when cycling again at 0.2 C magnification. The reversible specific capacity can reach 175 mAh/g and 98 mAh/g at -20 °C and -40 °C, respectively, demonstrating excellent low-temperature charging and discharging performance. [ABSTRACT FROM AUTHOR]

Tn this paper, the goal is to realize the 3d Printing of low-carbon magnesium phosphate cement materials prepared from light-burned magnesium oxide as raw material. With the help of the self-developed mixing and extrusion function-based building 3d Printing equipment, the influence of different fly ash content on the properties and printing properties of magnesium phosphate cement materials prepared from light-burned magnesium oxide was investigated. The influence of fly ash on its hydration products and crystal appearance was further analyzed by XRT) and SEM micro-tests. The results show that the setting time of magnesium phosphate cement prepared from light burned magnesium oxide is greatly shortened compared with that of heavy burned magnesium oxide. The addition of fly ash has a little effect on the setting time of the material, which is about 2-3 min, but it has a negative effect on the compressive strength and interfacial bond strength. When the content of fly ash is 30% of the mass of magnesium phosphate cement, the compressive strength and interfacial bond strength decrease by about 34.24% and 48.94%, respectively. When the content of fly ash is less than 20%, it can effectively improve the dry shrinkage rate of light-burned magnesia-based magnesium phosphate cement material and increase the volume stability. The active substances in fly ash participate in the hydration reaction, and the generated hydration products show good chemical compatibility with magnesium phosphate cement, making the structure more compact. When the content of fly ash is 20%--25%, the prepared light burned MgO-based magnesium phosphate cement for 3d Printing has good working performance, volume stability, extrusion performance and construction performance, and meets the mechanical requirements of 3d Printing for cementbased materials. [ABSTRACT FROM AUTHOR]

The graphite conductive phase material is used to replace the fine aggregate to prepare the functional conductive concrete, and the concrete matrix can be heated by electricity heating to achieve the purpose of snow melting and ice melting. Resistivity is the main index to measure the electrical conductivity of concrete, which is easily affected by factors such as concrete moisture content and ambient temperature. Tn this paper, graphite, graphite ore and graphite tailings were used as conductive phases to prepare conductive concrete. The mechanical properties of three kinds of graphite conductive phase concrete, the resistivity evolution law and microscopic properties of graphite concrete under different temperatures and water contents were studied, and the conductive mechanism of graphite concrete was analyzed. The results show that the increase of conductive phase content, temperature and water content reduces the resistivity of concrete, and the incorporation of conductive phase reduces the resistivity most significantly. Tn addition, the results of SEM and EDS tests showed that the content of carbon in the concrete matrix increased significantly under different dosage conditions, which verified that the addition of graphite materials could promote the electrical conductivity of concrete, but it would cause holes and micro-cracks in the concrete matrix, which had an adverse effect on the strength of graphite concrete. [ABSTRACT FROM AUTHOR]

The mechanical properties and thermal stability of Fe/PbTe thermoelectric joints are poor due to the mismatch of thermal expansion coefficient and mechanical interlocking interface connection. Considering the controllability of the thermal expansion coefficient of the alloy, specific active elements are added to Fe to form metallurgical bonding at the interface through diffusion and reaction, which can improve the interface bonding performance. Tn this paper, we selected FMn. (x = 0, 5, 1(), 15) alloy as electrodes through high-throughput experiments and connected them with n-type 氏Te using spark plasma sintering (SPS) technology. The results show that the thermal expansion coefficient of FeMn alloy becomes closer to that of 那 Ga Te with the increase of Mn content, which effectively reduces the interface mismatch. The Fe-Pb-Ga element interdiffusion layer appeared at the interface after aging 1 5 d, which demonstrating metallurgical bonding characteristics. The contact resistivity of Fe供;Mn脚 Ga Te./FeMn is 10.12 • cm² after aging for 1 5 d. The conversion efficiency remains stable at about 4.3%, The shear strength increases to 21.44 MPa, Based on the high-throughput selection of alloy electrodes, the above technical route provides a new way to design the thermoelectric interface. [ABSTRACT FROM AUTHOR]

The electrical contact materials are widely used in various low-volt age switching devices such as electrical switches, relays, contactors and circuit breakers, and their characteristics are of great importance to the switching capacity, reliability, stability and service life of the overall electrical system. The conventional Ag- based contact materials have good performance, but still suffer from defects such as high contact resistance, low interfacial bonding strength, and poor plasticity, and their applications are limited to some extent. Tn recent years, domestic and foreign researchers have reported new group element contact materials such as Ag-Sn()2- Me(), Ag-GNPs, Ag-MAX and Ag-RE on the basis of the traditional Ag-based contact materials. This paper will review the current research status of new Ag-based contact materials in terms of their organization and properties as well as arc erosion performance, and finally summarize the key scientific issues and challenges facing new Ag-based contact materials and look forward to their future development trends. [ABSTRACT FROM AUTHOR]

Biomass-derived carbon materials have attracted more and more attention as efficient and cheap super--capacitor electrode materials due to their renewability and flexible microstructure tunability. However, the original biomass-derived carbon has the disadvantages of low porosity, low specific surface area and insufficient specific capacitance. The specific surface area, pore structure and conductivity of electrode materials will affect the energy storage performance of supercapacitors. Therefore, how to fabricate electrode materials with high specific capacitance, fast charge and discharge and certain flexibility has become the focus of current research. Tn this paper, the classification and energy storage mechanism of supercapacitors and the preparation methods and research status of biomass-based carbon materials are reviewed. The key performance evaluation parameters of high-quality load electrodes are analyzed, and the influencing factors of their electrochemical performance are systematically discussed. The future development trend is to integrate different types of energy storage devices into composite energy storage devices to meet the needs of various fields. Composite energy storage devices have greatly improved the comprehensive performance of supercapacitors. Therefore, the development of efficient and stable energy storage technology is of great significance for alleviating energy shortage, reducing environmental pollution and promoting sustainable development. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO), as a derivative of graphene (G), has excellent mechanical properties and thermal conductivity similar to graphene, and its hydrophilic functional groups make it easier to disperse in water and combine with cement-based materials. A large number of studies have shown that adding GO into cement matrix can not only enhance the mechanical properties and durability of cement matrix, but also enhance the electromagnetic shielding properties and thermal conductivity of cement matrix, which provides the possibility for the development of multifunctional and intelligent concrete. Focusing on the application of GO mixed with other functional fiber materials in cement-based materials, this paper briefly describes the performance characteristics and structural characteristics of GO, thus indicating the breadth and scope of its application in cementbased materials, emphatically summarizes the research on the dispersion of GO and the working performance, hydration process, mechanical properties, durability and functional properties of GO mixed with fiber cementbased materials, and looks forward to the future research direction of GO mixed with fiber cement-based materials. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO) has promising applications in improving the microstructure and mechanical properties of cementitious materials due to its excellent properties. However, the enhancement effect of GO is largely dependent on its dispersion in the cement matrix. This paper summarizes the research results of GO in cementitious materials in recent years, focusing on the review of GO dispersion methods, dispersion mechanisms, and the corresponding mechanical property improvement mechanisms, comparing the advantages and disadvantages of different GO dispersion methods, and analyzing the effects on the microstructure and mechanical properties of cementitious materials before and after GO dispersion. The problems of the current research are pointed out, and an outlook on future research trends is provided, aiming to provide a basis for subsequent GO in cementitious materials for stable applications, in order to promote the preparation of highly functionalized GO cementitious composite reinforced materials. [ABSTRACT FROM AUTHOR]

In this paper, a large number of hydrogen bonds were constructed between B4C particles and poly(vinyl alcohol) (PVA) matrix by means of surface modification to enhance the interaction between the two phases, and highly filled B4C/PVA fibers and their fabrics were successfully prepared by wet spinning technology, which provided both neutron protection and air- and moisture-permeability. The results show that cetyltrimethylammonium bromide (CTAB) is uniformly coated on the surface of B4C particles and alkyl tail entanglement with OP-10, which makes the high-filled B4C particles stable in suspension in PVA spinning solution and stable in spinning process, and the B4C/PVA fibers and their textile fabrics are obtained with up to 50% filling capacity. Neutron protection and air permeability and moisture permeability of textile fabrics need to be provided 50% wt% B4C-CTAB-OP-10/PVA fabrics with a single-layer neutron shielding rate of 49.43%. The present work provides a new solution for wearing comfort and radiation protection safety of the products. [ABSTRACT FROM AUTHOR]

In this paper, the intrinsic structure model of SiCp/Al composites was constructed based on the analysis of static and dynamic mechanical properties of SiCp/Al composites. Quasi-static tensile tests were conducted for SiCp/2a14Al composites with 20% volume fraction using an electronic universal testing machine to study the static mechanical properties of the material. Dynamic compression tests were conducted at different temperatures (20 °C-400 °C) and strain rates (500 /s-3000 /s) using a Hopkinson compression bar test to analyze the dynamic mechanical properties of the material. The Johnson-Cook (JC) intrinsic structure model of SiCp/Al composites was constructed based on the material stress-strain test data under static and dynamic conditions, and the model was optimized by genetic algorithm. The results show that the SiCp/Al composites exhibit a strain-reinforcement effect under quasi-static conditions; under dynamic loading conditions, the material flow stress increases with the strain rate and exhibits a strain-rate reinforcement effect, which is related to the volume fraction of silicon carbide particles. With the increase of temperature, the flow stress decreases and exhibits a temperature-softening effect. The average error between the least squares fitted JC model and the experimental values is large, and the model error is reduced after optimization by genetic algorithm, which can accurately predict the rheological behavior of SiCp/2a14Al composites. [ABSTRACT FROM AUTHOR]

AgInS2 quantum dots are an interesting material with a near-infrared band gap ranging from 1.87 to 1.98 eV. As a direct band gap semiconductor, it can adjust the band gap by adjusting the Ag/In ratio, and it also has a wide PL peak and a large Stokes shift. At the same time, the characteristics of low toxicity and environmental protection also make it an ideal material to replace binary quantum dots containing heavy metal elements such as Cd, Hg and Pb, and has a wide application prospect in the field of optoelectronic devices, especially in light emitting diodes. In this paper, the crystal structure and luminescence mechanism of AgInS2 quantum dots are described in detial, the characteristics of synthesis methods are summarized, and the strategies of regulating AgInS 2 quantum dots by shell engineering and doping methods are reviewed. Finally, the application progress of AgInS2 quantum dots in light-emitting diodes is introduced. [ABSTRACT FROM AUTHOR]

Aluminum matrix composites prepared via in-situ synthesis technology weigh the contradiction between strength and plasticity, which is expected to realize the integration of structure and function of aluminum matrix composites. In-situ synthesis of TiB2 particles reinforced aluminum matrix composites has high specific stiffness and modulus, excellent mechanical properties, corrosion resistance, wear resistance and fatigue resistance, which is one of the research hotspots of metal matrix composites in recent years and has broad application prospects in automobile manufacturing, highspeed trains, aerospace and national defense and military fields. In this paper, the characteristics and advantages of three reaction systems, Al-K2TiF6-KBF4 system, Al-TiO2 B2 O3 system and Al-Ti-B system, for in-situ synthesis of TiB2 particles reinforced aluminum matrix are summarized, the research status of the influence of TiB2 particles on the grain size, interfacial bonding and wettability of aluminum matrix is summarized, and the mechanism of TiB2 particles reinforced aluminum composites is discussed. The unsolved problems in this field are summarized, and the potential development space of TiB2 particles reinforced aluminum matrix composites prospected, so as to provide reference for the research and development of in-situ synthesized particles reinforced aluminum matrix composites. [ABSTRACT FROM AUTHOR]

Starch is a natural polymer material composed of α-glucose molecules with a wide range of sources, and mainly in the roots and stems of plants. It is inexpensive, renewable and biodegradable. The preparation of natural degradable plastic films from starch is of great significance to solve the problem of environmental pollution. Compared with starch-based materials, synthetic thermoplastic polymers such as polyethylene, polypropylene and polystyrene have disadvantages such as irritating odor, non-biodegradable and polluting the environment. Biodegradable thermoplastic materials made from starch have become a hot research topic for researchers. In this paper the structure and properties of starch is described, together with the plasticization methods, the ways to improve the barrier and mechanical properties of thermoplastic starch. Also the research progress and the outlook of thermoplastic starch-based materials are summarize. [ABSTRACT FROM AUTHOR]

Biomass is an excellent carbon source with abundant production, wide variety, low price and environmentally friendly, and the preparation of carbon catalytic material from biomass is undoubtedly turning waste into treasure, which can fundamentally solve the problems of environmental pollution and resource waste. This paper introduces the effects of biomass species, components and structure on the performance of biomass carbon-based catalytic materials, compares the two common methods of pyrolysis and hydrothermal carbonization for the preparation of biomass carbon-based catalytic materials, discusses the three ways to further enhance the catalyst activity, heteroatom doping, metal-ion modification, and functionalization, and analyzes and summarizes the challenges faced by biomass carbon-based catalytic materials. [ABSTRACT FROM AUTHOR]

With the rapid development of emerging industries such as big data, internet of things and new energy vehicles, related electronic devices and components are evolving towards high performance, high integration, lightweight and precision. The resulting electromagnetic interference can pose a threat to human health, information security and normal operation of various electronic devices. Therefore, high-performance electromagnetic shielding materials are urgently needed. Carbon fiber has excellent mechanical properties and good electrical conductivity, and is resin matrix composites have many advantages, such as light weight, high specific strength/modulus, good fatigue resistance, strong designability and excellent electromagnetic shielding performance. However, compared with traditional metal materials, carbon fiber composites have lower electromagnetic shielding performance. In order to further improve the electromagnetic shielding performance of carbon fiber composites, it is usually necessary to modify the surface of carbon fiber to increase its electrical conductivity. In this paper, the electromagnetic shielding mechanism of carbon fiber composites is introduced. The various surface modification methods of carbon fiber and their effects on the electromagnetic shielding performance of resin matrix composites are reviewed. The advantages and disadvantages of various carbon fiber surface modification methods are analyzed. The development trend of carbon fiber reinforced resin matrix electromagnetic shielding composites is further prospected. [ABSTRACT FROM AUTHOR]

With the development of modern industry, heavy metal water pollution has become one of the most important environmental problems. Heavy metal ions are highly toxic and difficult to degrade, being harmful to humans, aquatic animals, and plants to a large extent and damaging ecosystems. The advantages of low cost, high removal efficiency and recyclability of the adsorption method make it one of the important methods of wastewater treatment. Biomass materials are rich in resources, low cost, green and environmentally friendly, and have been widely studied as new adsorbent raw materials. Based on this, taking metal-organic framework, zeolite and biochar biomass materials as examples, this paper first reviews the preparation and modification methods of biomass matrix composites and summarizes the influence of the properties of adsorbents on metal ion adsorption, secondly elaborates the adsorption mechanism between them and metal ions, and finally puts forward the prospect of biomass matrix composites in the development of water pollution control. [ABSTRACT FROM AUTHOR]

Tn this paper, a flexible carbon cloth was used as the fluid collector of the composite electrode, and the high-conductivity carbon nanotubes (CNTs) were embedded into the polyvinylidiene fluoride (PVDF) binder by electrostatic flocking to obtain a composite structure with a larger electrochemically active surface area. Then, polyaniline (PANT) with pseudo capacitance characteristics was plated on the surface of CNTs by electrochemical deposition, and a binary composite electrode with carbon nanotubes/polyaniline (CNTs/PANT) was obtained. The structure of the electrode material was characterized by scanning electron microscopy (SEM). The flexible solid-state supercapacitor (SSC) with symmetrical structure was assembled with polyvinyl alcohol (PVA) hydrogel electrolyte containing sulfuric acid, and its electrical performance was tested by electrochemical workstation. The results show that the SSC has a specific capacity of 517 mF/cniJ at a current of 1 mA/cm2. After 250() cycles, it has a capacity retention rate of 79.8% and a Coulomb efficiency of more than 97%. The study shows that electrostatic flocking technology can be used as an effective way to prepare high performance electrode materials. [ABSTRACT FROM AUTHOR]

ZnO is limited in its application due to its own high charge complex and active chemical nature. Compounding by surface modification can realize electron-hole separation and improve its chemical stability. Tn this paper, Zn()/Ti()2 single heterojunctions were prepared by combining sol-gel, hydrothermal and liquid phase deposition with zinc acetate di hydrate, zinc nitrate hexahyd rate, and ammonium hexafluorotitanate as raw materials under low temperature conditions. XRD, SEM, EDS, TEM and PL were used to characterize the samples and test their optoelectronic properties. The results show that the morphology of Zn()/Ti()2 co re-she 11 structure is the most regular at the deposition time of 20 min, in which the diameter of ZnO is about 115 nm, and the thickness of Ti()2 film is about 7.6 nm. The loading of Ti()2, which reduces the photogenerated charge complex in the electrode and improves the collection of photons by ZnO, and the photocurrent density is enhanced by about 1 0 times to reach 0.21/.a A/cm", which exhibiting excellent photoelectro ch emi cal performance. [ABSTRACT FROM AUTHOR]

Tn this paper, N-CT)s and N-CT)s-X@Nb9 ()5-AMMC nano mate rials modified with different contents of N-CT)s have been successfully prepared by a simple hydrothermal method. N-CT)s-X@ Nb ()5-AMMC was characterized by XRT), SEM, TEM, FT-TR, XPS, UV-vis DRS and so on, and the results indicate that the band gap of Nb()5-AMMC is narrowed after N-CT)s modification, and the absorption band edge of the sample shows redshift and wider light absorption range, which is conducive to improving the photocatalytic performance. Tn addition, N-CT)s reduces the resistance of electron transport, which is conducive to the transfer of photogenerated electrons to the N-CT)s structure. At the same time, the migration and separation efficiency of photogenerated carriers are improved, which is conducive to the photocatalytic reaction. Compared with pure Nb ()5-AMMC. N-CT)s-X@ Nb O-AMMC has improved photocatalytic degradation performance of TC-HC1 under visible light, in which N-CT)s-l ©NbO-AMMC has the highest degradation efficiency. The degradation rate of N-CT)s-1 @ Nb ()5-AMMC for TC-HC1 reaches 63.2% within 1 h, which is 1.59 times of pure Nb ()5-AMMC. [ABSTRACT FROM AUTHOR]

Solid polymer electrolytes (SI〉Es) have received increasing attention due to their unique safety properties. Tn this paper, a novel SPE (PILCPEO SPE) was prepared by introducing poly(ionic liquid) (PTL) using poly(ethylene oxide) (PEO) as the matrix. By interspersing PTL in PEO chain segments, the crystallinity of PEO was effectively reduced, and the ionic conductivity of SPE was improved (6.63X1 0-'1 S/cm). The solidstate battery prepared showed a high first discharge capacity of 147.6 mAh/g for Li/LiFePOi cells at 0.5C, 6() °C, and the capacity retention remained above 9()% after up to 3()() turns of charge/discharge cycles. [ABSTRACT FROM AUTHOR]

Organic framework compounds have great application potential in photocatalytic water hydrogen production due to the advantages of controllable molecular structure, large specific surface area, high porosity, dispersed chemical active sites and good stability. Tn this paper, the metal-organic framework NH-UiO-SS was introduced into the synthesis process of the covalent organic framework PyPD-COF by solvothermal method, and NHv-UiO-SS/PyPD-C'OF heterojunction was formed in situ. The samples were characterized by TEM, EDS, XPS, FTTR, UV-Vis and photocurrent analysis, as well as photocatalytic performance test. The constructed NH-UiO-SS/PyPDC'OF heterojunction could not only retain the excellent properties of the original MOF and COF components, but also form bonds at the heterogeneous interface. Tt is beneficial to promote interfacial charge transfer, reduce electron-hole recombination rate, and increase photocatalytic hydrogen production efficiency to 20.68 mmol/(h • g), which is 86 times and 3 times of the original NH2-Ui()-66 and PyPD-COF, respectively. At the same time, the covalent bond at the interface makes the composite sample have good hydrogen production stability, which provides a new strategy for the construction of efficient photocatalytic decomposition of aquatic hydrogen heterojunction photo catalysts. [ABSTRACT FROM AUTHOR]

Tn this paper, the dispersion mechanism of thermal reduction graphene oxide (TRGO) and graphene oxide (GO) in cement mortar environment was studied, and the effect of single and multiple mixing of these two conductive phases on the mechanicai/electricai properties of mortar was explored. The results show that GO can promote the dispersion of TRGO in calcium-rich and high-alkali environment, and the optimal dispersion mass ratio is 3: 1 0 wt%. Compared with TRGO mixed alone, the compound mixing of GO promotes the formation of sheet structure and interweaving of mortar hydration products, which significantly improves mechanical properties. When GO: TRG() = ().: 3: 1.0 wt%, the flexural and compressive strength of 28 d cements increases by 21.34% and 34.52% compared with single mixed TRGO, but the mechanical properties decrease with the increase of mixing amount. The electrical conductivity of cement mortar increases with the increase of GO and TRGO conductive phases. When GO: TRGO = 0.12: ().4 wt%, the resistivity of the 28-day age cement shows a sudden change, indicating that the system has a percolation threshold. Under the optimal dispersion ratio, when TRGO' amount exceeds ().7 wt%, the increasing content on the resistivity tends to be flat and lower, implying that ().7 wt% TRGO is the threshold of adding content to the resistivity. [ABSTRACT FROM AUTHOR]

In this paper, a green carboxymethyl cellulose sodium (CMC)/gelatin (GL)-glut ar aldehyde (GA) composite aerogel (CL-A) was prepared by using the principle of chemical cross-linking and freeze-drying technology. The effects of different proportions of carboxymethyl cellulose sodium (CMC), gelatin (GL) and different contents of glutaraldehyde (GA) on the microstructure, thermal stability, mechanical strength and thermal insulation and thermal insulation properties of the aerogel were investigated. The experimental results obtained after trying different raw material ratios showed that the compression modulus of the composite aerogel (Cj I弋一Ain)with the ratio of sodium carboxymethyl cellulose (CMC) to gelatin (GL) of 1:2 and the addition of glutar-aldehyde (GA) of 15% is the highest of 3.()3 Mpa, which is 7 times higher than that of pure sodium carboxym-ethyl cellulose (CMC) aerogel, and the mechanical properties have been enhanced effectively. The thermal conductivity of composite aerogel (Ci I<_) is the lowest, which is as low as ().022 W/(m • k) with a better heat preservation effect. At the same time, the composite aerogel (Ci I-) has a denser porous three-dimensional network, which improves the morphology of the composite aerogel to a certain degree. Lastly, the composite aerogel (C J弋-八")has up to 37% residual carbon, which improves the thermal stability to some extent. Tn summary, the compression modulus, microstructure, thermal stability, and thermal insulation properties of the composite aerogel (C-! I<-AI5) after the addition of gelatin (GL) and glutaraldehyde (GA) are improved. [ABSTRACT FROM AUTHOR]

Tn recent years, graphene/polyurethane nanocomposites have attracted much attention due to their superior comprehensive properties. Incorporating graphene or its derivatives into I〉U matrix could significantly improve the physical mechanical, thermal, electromagnetic and other properties, which meets the special requirements of high-performance and multi-functional polymer composites. Tn this paper, the functional modification methods of graphene nanosheets, including covalent modification and non-covalent modification were first introduced. Furthermore, the fabrication processes of graphene/poly urethane nanocomposites, including in-situ polymerization, solution blending, melt blending, aqueous (latex) blending, etc., were briefly introduced. The recent research progress of graphene/poly urethane composites in mechanical, electrical, dielectric, thermal, gas barrier, flame retardant, electromagnetic interference shielding and corrosion resistant properties were all reviewed in detail. The future challenges and development prospects of high-performance graphene/poly urethane nanocomposites were also prospected. [ABSTRACT FROM AUTHOR]

In recent years, with the research on the application of superhydrophobic materials in condensation heat transfer, oil-water separation, deicing and anti-fogging, surface corrosion prevention, pipeline resistance reduction and other aspects gradually becoming mature. The application prospect of superhydrophobic materials in the biomedical field has also attracted the attention of scholars. Coagulation thrombus and hemorrhagic shock caused by massive hemorrhage when medical equipment contacts with blood will pose great threat to the life safety of patients. Tn order to effectively solve that problems of thrombus occurrence and massive blood loss, many scholars at home and abroad have carried out a great deal of research. Due to the special surface wettability and lower surface free energy of the super-hydrophobic material, the platelet adhesion amount on the surface of the material can be significantly reduced. The combination of the super-hydrophobic material and hydrophilic material can reduce the bleeding amount and the possibility of secondary laceration bleeding of a wound on the premise of hemostasis. Meanwhile, the research shows that the super-hydrophobic material also has good antibacterial property. Therefore, the research on superhydrophobic materials has become a hot spot and direction in this field. Based on this, this paper first introduces the basic theory of superhydrophobic surfaces, mainly including the Young wetting model, Wenzel wetting model and Cassie-Baxter wetting model, then the mechanism of superhydrophobic materials in the process of anti-coagulation and pro-coagulation is expounded in detail. The current research status of superhydrophobic materials in the field of blood contact is discussed, and the main problems in the application of superhydrophobic materials in this field are pointed out. Finally, the future development of superhydrophobic materials is prospected. [ABSTRACT FROM AUTHOR]

With the continuous implementation of the "double carbon" policy and the continuous improvement of peoples awareness of environmental protection, carbon monoxide (CO), as a typical air pollutant, has become the main control object of industrial and automobile exhaust emissions. Noble metal catalysts for CX) oxidation are one of the most effective means for CO catalytic oxidation treatment due to their excellent low-temperature activity, anti poisoning and anti-corrosion properties. Based on the research status of noble metal type CX) oxidation catalysts, this paper focuses on the noble metal regulation technology and carrier controllable technology of Pt, Pd, Au, Ag and Rh noble metal catalysts, summarises the performance optimization ways and development directions of noble metal type CO oxidation catalysts, and provides guidance for the development of better performance CO oxidation catalysts. [ABSTRACT FROM AUTHOR]

Semi conduct or-based photocataiytic technology was selected as a "green" sustain able solution for environmental remediation and energy storage with solar energy. Tn this paper, the advantages and limitations of g-C-3 N-i, as well as the advantages and disadvantages of S-type semiconductors are first introduced, then the electronic structure and photocataiytic properties of g-C3 Ni-based S-type heterojunction photocataiytic materials are introduced. Then the strategies with which to improve the photocataiytic performance of S-type heterojunction photocataiytic materials based on different types of g-C3 N.-i are reviewed, and some of their applications are reviewed. Finally, this review gives the challenges and future development trends of S-heterojunction based on g-C3 N-i, which is expected to provide important references for the development and practical application of g-C3 Ni-based S-heterojunction photocataiytic materials. [ABSTRACT FROM AUTHOR]

Elastomer damping materials have unique dynamic viscoelastic behavior and are widely used in many fields such as vibration damping and noise reduction. Tn practical applications, elastomer damping materials often face the problems of narrow effective damping temperature range and low loss factor. Widening the effective damping temperature range and increasing the loss factor are the main directions for the development of high performance elastomer damping materials. Based on the damping mechanism of elastomer damping materials, this paper expounds the influence of molecular structure, operating temperature and vibration frequency, and e-lastomer composition system on the damping performance of elastomer damping materials. The modification methods of elastomer damping materials and the latest research progress in recent years are also introduced. [ABSTRACT FROM AUTHOR]

Due to the poor light transmission, anti-protein adsorption capacity and flexibility, methacryloylated gelatin (GelMA) hydrogel is limited in artificial cornea. This paper aims to introduce methacryloxyethyl sulfo--betaine (SBMA) with excellent bioadsorption resistance and outstanding bio compatibility to GelMA hydrogel, and construct a series of zwitterionic hydrogel Ge 1MA-SBMA system. The physicochemical and biological properties of hydrogels are discussed, and the vitro cell experiments are conducted to discuss the effects of composite hydrogels on cell growth and proliferation. The results show that GelMA-SBMA hydrogel in ratio of 5: 1, at a wavelength of 700 nm, presents a light transmittance of 94%. The good anti-protein adsorption ability is reflected by the contact angle with fibrin above 9()1 The vitro cell experiments show that SBMA is more conducive to cell growth and proliferation with good biocompatibility. [ABSTRACT FROM AUTHOR]

The carbon coating strategy is an effective way to solve the pulverization problem caused by the volume expansion/shrinkage of transition metal oxide (TMO) materials for lithium-ion battery anodes during charge and discharge. Tn this paper, bio-based edible ice jelly powder was used as carbon source and ferric ammonium oxalate hydrogel was used as precursor, and nitrogen-doped ice jelly powder-based carb on-coated Fe3 ()i was prepared by one-step high-temperature pyrolysis. The morphology, structure and electrochemical properties of the samples were studied by XRD, SEM, TEM, XPS, TG A, Raman spectroscopy, ga Iva no static charge-discharge test, cyclic voltammetry and electrochemical impedance spectroscopy. The results show that this method can quickly and massively prepare nitrogen-doped carbon-coated Fe$Oi porous composites (N-C@Fe3 O.-i), and excellent electrochemical performance can be obtained by adjusting the ratio of raw materials and heat treatment conditions. N-C@Fe3O.j-5 as a lithium ion battery anode material has good cycle stability (762.74 mAh/g specific capacity after 80 cycles at a current density of ().1 A/g) and high rate capability. Relevant mechanism studies have shown that the good rate performance of N-C@ Fes O.-i composites is mainly due to the contribution of pseudo capacitive capacity. The excellent electrochemical performance of the composite is attributed to the carbon coating that prevents nanoparticle agglomeration, improves electrical conductivity, and forms a stable solid electrolyte interface (SET) film. This work shows that ice jelly powder-based carb on-coated TMO is an effective way to improve the electrochemical lithium storage performance of TMO, which can be extended and improved the lithium storage performance of other lithium-ion battery oxide anodes. [ABSTRACT FROM AUTHOR]