properties

摘要： In this study,different molar of methylolureas(MMU)were used to improve the properties and drying speed of the raw lacquer(RL).The drying time,gloss,pencil hardness and impact resistance of the lacquer film were tested.The thermal behaviors and chemical structures of the lacquer membrane were also discussed by thermal gravimetric analysis(TGA),fourier infrared spectrometer(FT-IR)and nuclear magnetic resonance(NMR)analysis,respectively.The results demonstrated that lower molar ratio MMU can significantly improve the properties of lacquer.The TGA analysis showed that the modified lacquer had high thermal stability than that of the control.The FT-IR and 13C NMR analysis revealed that the structures of the modified lacquer were significantly improved by cross-linking with the hydroxymethyl groups and methylene methyl ethers of MMU.In addition,through scanning electron microscopy(SEM)characterization,it was found that the introduction of MMU can effectively improve the surface smoothness of the lacquer film.

摘要： A novel Ti-6.38Al-3.87V-2.43Mo alloy was designed with a cluster formula of 12[Al-Ti12](V0.75Mo0.25Ti2)+4[Al-Ti12](Al3)by replacing Ti with Mo/V on the basis of the Ti-Al congruent alloy.The effects of laser power and scanning speed on the molten pool size,surface roughness,relative density,microstructure,and micro-hardness of single-track and bulk Ti-6.38Al-3.87V-2.43Mo samples prepared via laser additive manufacturing(LAM)were investigated.The results show that processing parameters significantly affect the formability,microstructure,and micro-hardness of the alloy.With decreasing laser power from 1,900 W to 1,000 W,the relative density is decreased from 99.86%to 90.91%due to the increase of lack-of-fusion;however,with increasing scanning speed,the relative density does not change significantly,but exceeds 99%.In particular,Ti-6.38Al-3.87V-2.43Mo samples of single-track and bulk exhibit a good formability under an input laser power of 1,900 W and a scanning speed of 8 mm·s_(-1),and display the lowest surface roughness(Ra=13.33μm)and the highest relative density(99.86%).Besides,the microstructure of LAM Ti-6.38Al-3.87V-2.43Mo alloy coarsens with increasing laser power or decreasing scanning speed due to the greater input energy reducing the cooling rate.The coarsening of the microstructure decreases the microhardness of the alloy.

摘要： Perovskites have been widely utilized as active materials in various optoelectronic devices, e.g. light-emitting diodes(LEDs), photodetectors(PDs), and solar cells(SCs), etc., due to their facile processability and outstanding optoelectronic properties.

摘要： We review recent developments on the synthesis and properties of two-dimensional materials which, although being mainly of an sp^(2) bonding character, exhibit highly disordered, non-uniform and structurally random morphologies. The emergence of such class of amorphous materials, including amorphous graphene and boron nitride, have shown superior properties compared to their crystalline counterparts when used as interfacial films. In this paper we discuss their structural,vibrational and electronic properties and present a perspective of their use for electronic applications.

摘要： The composition and structure of substrate materials have important influences on coating performance,especially in terms of bond-ing strength and coating hardness,which determine whether the coating can be used for a given application.In this study,a TiAlN coating is deposited on Ti(C,N)-based cermet(TC)substrates with 0wt%-20wt%WC by arc ion plating.The influence of cermet substrate characterist-ics on the structure and properties of the TiAlN coating is then researched.Results show that the TiAlN coating deposited on the TC substrate has a columnar grain structure.As WC increases,the strength ratio of I(111)/I(200)and adhesive strength of TiAlN gradually increases.In the ab-sence of WC in the substrate,the preferred orientation of the TiAlN coating is(200).As WC increases,the preferred orientation of the TiAlN coating becomes(111)and(200).Notable differences in adhesive strength between the coating and substrate could be attributed to the micro-structure and composition of the latter.Scratching results show that the adhesive strengths of the TiAlN coating on the 0wt%-20wt%WC cer-met substrate are 52-65 N.Among the coatings obtained that on the TC substrate with 15wt%WC presents the highest H/E and H3/E2,which indicates that this coating also features the best wear resistance.The failure mechanisms of the coated tools include coating peeling,adhesive wear,and abrasive wear.As the cutting speed increases,the degree of flank wear increases and the durability of the coating decreases accord-ingly.Increases in WC result in an initial decrease followed by a gradual increase in the flank wear of the coated cermet inserts.

摘要： The influence of food and nutrition on health and immunity for both human and animals are being demonstrated. Phytochemicals are natural compounds present in cereals, beans, fruits, vegetable, and other plants, believed to enhance immune response for both human and animals. One of these phytochemicals is β-Glucans that are heterogeneous polysaccharides consisted of branched long chains of D-Glucose units present in cereals such as barley, wheat, and oats, and also present in microbial cell walls for yeasts, fungi, bacteria, and algae. β-Glucans extracted from cereals and mushroom were investigated for their positive impact on immunomodulation for both human and animal health. These β-Glucans proved to enhance immune system for innate response as the first defense against microbial infection, toxins, and self-tumor cells, and also, enhance adaptive immune that also referred to specific immunity as the second defense in response to antigen-specific lymphocytes against microbial infection, toxins, and self-tumor cells.

摘要： Identification of regulatory genes from chalky/floury endosperm mutants is an important approach to understand the mechanism of starch biosynthesis to accelerate rice grain quality improvement.A mutant GM645,identified from 60Coγ-irradiation of an indica rice Guanglu’ai 4(GLA4),exhibited white-core endosperm and altered starch physicochemical properties.However,the causal gene responsible for the white-core endosperm in GM645 has not been identified.Here,we developed a recombined inbred line(RIL,F7)population derived from a cross between GM645 and a japonica rice Tainong 67(TN67)with translucent endosperm.Bulkedsegregant analysis combined with next generation sequencing revealed five single nucleotide polymorphisms(SNPs)in four candidate genes that were highly associated with the white-core endosperm.Among them,one base pair deletion in Os04g0645100 resulted in a frame shift mutation after the 983th amino acid(aa),and a premature stop codon occurred after the other 11 aa.Moreover,functional annotation revealed that Os04g0645100 was previously characterized as the FLOURY ENDOSPERM2(FLO2)gene.Full-length coding sequence from Os04g0645100 driven by the maize ubiquitin promoter was transformed into GM645,and seeds from these transgenic plants expressing Os04g0645100 were largely rescued to translucent,indicating that Os04g0645100 was responsible for the whitecore endosperm in GM645.

摘要： High-entropy alloys (HEAs) are emerging materials that are developed based on entropy, anddraw significant attention for the potential to design their chemical disorder to bring outdifferent structural and physical characteristics. Over the past two decades, significant salientefforts have been conducted to explore many unique and useful properties of HEAs, such asovercoming the strength–ductility trade-off, outstanding thermal stability, and excellent lowtemperature plasticity. Here, we review the key research topic of HEAs in the following threeaspects: (a) performance advantages and composition design, (b) performance-driven HEAs and(c) fabrication process-driven HEAs. Towards their industrial applications, our article reviews alarge range of methods to synthesise, fabricate and process HEAs. We also discuss the currentchallenges and future opportunities, mainly focusing on performance breakthroughs in HEAs.

摘要： Starch is the most abundant organic compound in nature,second only to cellulose.However,the conserved structure of native starches limits their properties and applications.Therefore,it is often necessary to modify them to obtain specific properties.As a common green and safe physical modification method,pre-gelatinization can improve the cold water solubility and swelling power of starch.The typical preparation methods of pre-gelatinized starch include spray drying,extrusion,and drum drying.Spray-dried pre-gelatinized starch still had good granule shape,but the increase of cold water solubility and cold paste viscosity was relatively small.Extruded and drum-dried pre-gelatinized starch showed serious structure destruction,significant increases in cold water solubility and cold paste viscosity,but relatively low hot paste viscosity.The properties of pre-gelatinized starch obtained by different methods are different,so do their effects on the quality of flour products.Wheat flour products,as one of the leading staple food for the people all over the world,play a vital role in people's daily life.With the improvement of people's living standards,more and more special flour products with unique features have received attentions of consumers and researchers.However,the sensory characteristics of special flour products are often inferior to traditional flour products,which limits its development.The unique functional characteristics of pre-gelatinized starch make it expected to play an essential role in the quality improvement of featured flour products.In this paper,the granule morphology,crystal structure,hydration and gelatinization properties of pre-gelatinized starch prepared by three common methods and their application in flour products were reviewed,which provides a theoretical basis for the application of pre-gelatinized starch in food industry.

摘要： Fibers are used in many forms in engineering applications–one of the most common being used as reinforcement.Due to its renewable short natural growth cycle and abundance of bamboo resources,bamboo fiber has attracted attention over other natural fibers.Bamboo fiber has a complex natural structure but offers excellent mechanical properties,which are utilized in the textile,papermaking,construction,and composites industry.However,bam-boo fibers can easily absorb moisture and are prone to corrosion limiting their use in engineering applications.Therefore,a better understanding of bamboo fiber is particularly important.This paper reviews all existing research on the mechanical characterization of bamboo fiber with an emphasis on the extraction and treatment techniques,and their effect on relevant properties.The chemical composition of bamboo fibers has also been thoroughly investigated and presented herein.Current applications and future opportunities for bamboo fibers in various fields have been presented with a focus on research needs.This work can serve as a reference for future research on bamboo fiber.

摘要： 本发明公开了一种基于Spring的property文件的密码加密方法，所述方法通过在Spring中新写一个类，继承spring的PropertyPlaceholderConfigurer类，并覆盖PropertyPlaceholderConfigurer类的convertProperty方法，然后将property文件注入到新写的类中，从而实现密码加密。本发明方法适用Spring构建的web项目，避免密码泄露，能够通过简单有效的可统一密码加密的一个类，而不需其他地方修改。