Fast electron-hole recombination issues during titanium dioxide(TiO_(2))photocatalysis limit its application in preventing bacterial infection during bone defect *** this study,TiO_(2)@reduced graphene oxide(rGO)compo...
详细信息
Fast electron-hole recombination issues during titanium dioxide(TiO_(2))photocatalysis limit its application in preventing bacterial infection during bone defect *** this study,TiO_(2)@reduced graphene oxide(rGO)composites were synthesized using a hydrothermal method in which rGO,which possesses very high electrical conductivity,promotes the separation of photoelectron-hole pairs of TiO_(2),thus improving the efficiency of photocatalytic production of reactive oxygen species(ROS).Subsequently,TiO_(2)@rGO composites were introduced into poly-l-lactic acid(PllA)to prepare bone scaffolds with photocatalytic antibacterial function via selective laser *** results showed that TiO_(2)grew on the surface of rGO and formed a covalent bond connection(Ti-O-C)with rGO.A decreased electrochemical impedance of TiO_(2)@rGO composites was observed,and the transient photocurrent intensity increased from 0.05 to 0.5μA/cm^(2).Analysis of electron spin resonance found that the photocatalytic products of TiO_(2)were·OH and·O^(2-),two kinds of ROS capable of killing bacteria via disrupting the structure of the bacterial membrane in *** experiments showed that the PllA/TiO_(2)@rGO scaffolds had good antibacterial properties against Escherichia coli and Staphylococcus ***,we report that these scaffolds exhibited both enhanced mechanical properties due to the addition of TiO_(2)@rGO as a reinforcement material and good biocompatibility during cell proliferation.
Nitrate and nitrite， as long-standing additives used in food industry and particularly prevalent in meat products， are often perceived negatively by consumers due to their potential to produce carcinogenic nitrosami...
Nitrate and nitrite， as long-standing additives used in food industry and particularly prevalent in meat products， are often perceived negatively by consumers due to their potential to produce carcinogenic nitrosamines. Within the past decades， the importance of nitric oxide (NO) has been established for human health， including cardiovascular health， immunizing and defending system， skeletal muscle contraction and relaxation， nervous system， and cognitive function. Gradually， nitrate and nitrite， as the main NO donors， have also been demonstrated to have numerous health benefits in clinical studies. likewise， NO has showed positive effect on postharvest fruits and vegetables. In view of different controversies， this review comprehensively discussed the effect of nitrate， nitrite on meat products and NO on fruits and vegetables， the intake of nitrate and nitrite by diet， the physiological functions， synthesis and metabolism of nitrate， nitrite， and NO in human body. It is hoped to provide some new understanding for nitrate， nitrite， and NO in food preservation and human health.
Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse ***,the development of simple and efficient reactions to prepare hyperbranched polymers is of great *** this work,tria...
详细信息
Functional hyperbranched polymers,as an important class of materials,are widely applied in diverse ***,the development of simple and efficient reactions to prepare hyperbranched polymers is of great *** this work,trialdehydes,diamines,and trimethylsilyl cyanide could easily undergo multicomponent polymerization under mild conditions,producing hyperbranched poly(α-aminonitrile)s with high molecular weights(M_(w) up to 4.87×10^(4))in good yields(up to 85%).The hyperbranched poly(α-aminonitrile)s have good solubility in commonly used organic solvents,high thermal stability as well as morphological ***,due to the numerous aldehyde groups in their branched chains,these hb-poly(α-aminonitrile)s can undergo one-pot,two-step,four-component post-polymerization with high *** work not only confirms the efficiency of our established catalyst-free multicomponent polymerization of aldehydes,amines and trimethylsilyl cyanide,but also provides a versatile and powerful platform for the preparation of functional hyperbranched polymeric materials.
Ensuring the safety and performance of lithium-ion batteries(lIBs)is a significant challenge for electric *** tackle this issue,an innovative liquid-immersed battery thermal management system(lIBTMS)using bionic baffl...
详细信息
Ensuring the safety and performance of lithium-ion batteries(lIBs)is a significant challenge for electric *** tackle this issue,an innovative liquid-immersed battery thermal management system(lIBTMS)using bionic baffles with fish-like perforations is *** thermal-flow-electric coupling characteristics of lIBTMSs with different baffle structures(no baffle,conventional baffle,baffle with circular perforations and baffle with fish-like perforations)are systematically investigated using experimental and numerical *** results indicate that the forced flow scheme exhibits better thermal management performance and voltage equalization than static ***,the lIB temperatures and voltage deviations of different lIBTMSs increase quickly with increasing discharge *** importantly,the innovative lIBTMS exhibits the best thermoelectric performance due to its excellent thermoelectric equilibrium behavior caused by high electrical and temperature consistency,as well as the best overall performance involving the balance between the pressure loss and heat transfer capacity of the *** with other structures,the innovative lIBTMS using baffles with fish-like perforations exhibits a maximum reduction of 10.1%,15.2%,25.8%and 9.0%in lIB maximum temperature,maximum temperature difference,system pressure drop and voltage deviation,respectively,under the same operating ***,for the lIBTMS using baffles with fish-like perforations,the bottom inlet and top outlet configuration and coolant precooling are suggested to enhance cooling performance.
The “sergeants-and-soldiers” effect is a significant feature of helical copolymers, where a small fraction of chiral components can endow the copolymers with an intense optical activity close to that of chiral homop...
The “sergeants-and-soldiers” effect is a significant feature of helical copolymers, where a small fraction of chiral components can endow the copolymers with an intense optical activity close to that of chiral homopolymer. With the development of helical polymers, some abnormal examples have also been discovered, in which the twisting sense of main chain can be inversed with the increment of chiral unit content, termed as abnormal “sergeants-and-soldiers” effect. In this review, we detailedly summarize the development of “sergeants-and-soldiers” effect and its theoretical model in chiral polymer systems, including normal and abnormal “sergeants-and-soldiers” effects, modification of Ising model, dynamic transformation of the above two chiral amplification effects, as well as their applications in chiral separation, asymmetric catalysis, and circularly polarized ***, the remaining challenges are discussed to provide an outlook on the future directions.
维普期刊数据库
同方期刊数据库
暂无评论