摘要：Optical control of exotic properties in strongly correlated electron materials is very attractive owing to their potential applications in optical and electronic ***,we demonstrate a vertical heterojunction made of a correlated electron oxide thin film VO_(2) and a conductive 0.05 wt% Nb-doped TiO_(2) single crystal,whose metal-insulator transition(MIT)across the nanoscale heterointerface can be efficiently modulated by visible light *** magnitude of the MIT decreases from ~350 in the dark state to ~7 in the illuminated state,obeying a power law with respect to the light power *** junction resistance is switched in a reversible and synchronous manner by turning light on and *** optical tunability of it is also exponentially proportional to the light power density,and a 320-fold on/off ratio is achieved with an irradiance of 65.6 mW cm^(-2) below the MIT *** the VO_(2) thin film is metallic above the MIT temperature,the optical tunability is remarkably weakened,with a one-fold change remaining under light *** results are co-attributed to a net reduction(~15 meV)in the apparent barrier height and the photocarrier-injection-induced metallization of the VO_(2) heterointerface through a photovoltaic effect,which is induced by deep defect level transition upon the visible light irradiance at low ***,the optical tunability is minimal,resulting from the quite weak modulation of the already metallic band structure in the Schottky-type junction above the MIT *** work enables a remotely optical scheme to manipulate the MIT,implying potential uncooled photodetection and photoswitch applications.

摘要：Maltose is a natural α-(1,4)-linked disaccharide with wide applications in food industries and microbial fermentation. However,maltose has scarcely been used for in vitro biosynthesis, possibly because its phosphorylation by maltose phosphorylase (MP)yields β-glucose 1-phosphate (β-G1P) that cannot be utilized by α-phosphoglucomutase (α-PGM) commonly found in in vitrosynthetic enzymatic biosystems previously constructed by our group. Herein, we designed an in vitro synthetic enzymaticreaction module comprised of MP, β-phosphoglucomutase (β-PGM), and polyphosphate glucokinase (PPGK) for thestoichiometric conversion of each maltose molecule to two glucose 6-phosphate (G6P) molecules. Based on this syntheticmodule, we further constructed two in vitro synthetic biosystems to produce bioelectricity and fructose 1,6-diphosphate (FDP),respectively. The 14-enzyme biobattery achieved a Faraday efficiency of 96.4% and a maximal power density of 0.6mW/cm^(2),whereas the 5-enzyme in vitro FDP-producing biosystem yielded 187.0mM FDP from 50 g/L (139mM) maltose by adopting afed-batch substrate feeding strategy. Our study not only suggests new application scenarios for maltose but also provides novelstrategies for the high-efficient production of bioelectricity and value-added biochemicals.

摘要：The ability to widely tune the optical properties of amorphous alloys is highly desirable especially for their potential applications in optoelectronic *** this work,we demonstrate that introducing oxygen into an amorphous alloy system of Co-Fe-Ta-B enables the formation of various amorphous derivatives ranging from metals to semiconductors,and eventually to *** oxygencontaining amorphous derivatives gradually become transparent with the opened bandgaps,leading to a continuous increase in their optical ***,the reflective metal-type amorphous alloy and transparent insulator-type amorphous oxide of the system can be integrated together to realize the full-color tuning over the entire visible spectral *** provides a new way to develop large-area color coatings with high design flexibility and full-color *** envisage that the design concept proposed in this work is also applicable to many other amorphous alloy systems,from which all types of amorphous materials including alloys,semiconductors and insulators may be developed to show unprecedented optical functionalities.

摘要：在核燃料后处理流程中,需对工艺中的铀浓度进行准确测量。利用X射线管照射铀溶液,通过测量铀的L边界X射线透射谱确定铀浓度。文章设计了铀的L边界X射线透射谱测量系统。通过配制1~200g·L^(-1)铀标准溶液,建立铀浓度测量工作曲线,并对系统的精密度、准确度和稳定性进行测试。结果表明,铀浓度测量工作曲线线性拟合参数R2=0.999 9;系统对57.004g·L^(-1)铀溶液测量精密度为0.21%,对38.255g·L^(-1)铀溶液测量相对误差为0.32%;对2.236g·L^(-1)铀溶液进行连续测量,99.67%数据落在μ±3s。

摘要：基于遗传算法和数值分析一体式优化平台,以设计压力因子为目标函数,结构失稳和材料静强度破坏为约束条件,纤维缠绕策略和铺层方式为变量,对静水压力作用下碳/环氧、硼/环氧和玻璃/环氧等三种复合材料壳体的耐压因子进行优化设计。结果表明,复合材料耐压壳体在深海环境下能够提供充足的正浮力;对于不同的复合材料,最大设计压力受限的因素有所不同,主要受限于结构失稳或材料强度破坏;纤维缠绕策略和铺层方式对设计压力因子具有显著影响。文中最后提出变厚度设计、复合材料肋骨等增强方式,旨在解决结构失稳或材料强度破坏对最大设计压力的限制,研究成果可为复合材料耐压壳体结构设计提供参考。

摘要：利用InP基共振隧穿二极管(RTD)和加载硅透镜的片上天线设计实现了超过1 THz的振荡器。采用Silvaco软件对RTD模型进行仿真研究,分析了不同发射区掺杂浓度、势垒层厚度、隔离层厚度以及势阱层厚度等对器件直流特性的影响规律。对研制的RTD器件直流特性测试显示:峰值电流密度J_(p)为359.2 kA/cm^(2),谷值电流密度J_(v)为135.8 kA/cm^(2),峰谷电流比PVCR为2.64,理论计算得到的器件最大射频输出功率和振荡频率(f_(max))分别为1.71 mW和1.49 THz。利用透镜封装的形式对采用Bow-tie片上天线和RTD设计的太赫兹振荡器进行封装,测试得到振荡频率超过1 THz,输出功率为2.57μW,直流功耗为8.33 mW,是国内首次报道超过1 THz的振荡器。

摘要：有机电极具有结构可设计性强、容量大、可容纳大离子等优点.然而,在钠离子电池中,有机电极材料的容量仍然很低,且其在有机电解质中的高溶解度导致其寿命较短.如何通过化合物设计来提高其性能一直是研究人员关注的问题.本研究通过简单方法将氨基酸接枝到有机化合物上,提高了其容量和循环稳定性.首先,氨基酸之间的氢键使其形成更稳定的层状结构;氨基酸基团在有机电极材料和羧甲基纤维素粘合剂之间形成分子间相互作用,降低界面阻力,显著提高循环稳定性,使得钠离子电池循环次数超过2000次.其次,实验和计算结果表明,氨基酸基团提供了Na^(+)转运途径和额外的可逆存储位点,从而提高了比容量(~300 mA h g^(-1)).本策略可以启发未来钠离子电池的有机分子设计.

摘要：The buffeting performance of kilometer-level high-speed railway suspension bridges has a great impact on the smooth operation of high-speed *** investigate the buffeting performance of the structure significantly different from traditional suspension bridges,the first long-span high-speed railway suspension bridge,Wufengshan Yangtze River Bridge(WYRB),is taken as a numerical example to demonstrate the effects of structural parameters and wind field parameters on the buffeting *** on the design information,the spatial finite element model(FEM)of WYRB is established before testing its *** fluctuating wind fields are simulated via both classical and stochastic wave based spectral representation method(SRM).Finite element method is further taken to analyze the parametric sensitivity on wind induced buffeting responses in time *** results show that the vertical displacement is more sensitive to the changing dead load than the lateral and torsional *** larger stiffness of the main girder and the lower sag-to-span ratio are both helpful to reduce the buffeting *** spectrum and coherence function are key influencing factors to the responses so setting proper wind field parameters are essential in the wind-resistant design *** analytical results can provide references for wind resistance analysis and selection of structural and fluctuating wind field parameters for similar long-span high-speed railway suspension bridges.

摘要：快速、高通量的实验方法对材料基因工程技术的发展具有重要意义。高温热处理对无机非金属材料的制备往往是必不可少的环节,然而针对材料基因工程所需的材料样品库快速热处理技术目前尚是空白。本文报道了一种可用于快速高温热处理阵列样品的多束激光并行加热系统,介绍了多束激光并行加热系统的设计原理、工作方式、结构细节和软件设计。该装置具有激光加热时间、功率、光斑大小可独立调节、自动化程度高等优点,最大单束激光功率大于100W,每束激光的最大稳定加热温度约为2000℃。作为典型的应用示范,进行了一系列Ce^(3+)掺杂钇铝石榴石发光陶瓷的烧结实验,加热温度分别为1400、1500和1600℃,保温时间分别为180、360和540s,仪器按照设置好的加热位置和加热曲线自动运行。结果表明:采用多束激光并行加热系统,可以在几分钟的热处理时间内获得结晶度和发光性能良好的烧结样品,比传统制备工艺十余小时的烧结时间大幅缩短。这将为高温热处理的条件筛选和高通量制备提供一种节能省时的新技术方案。

摘要：Recently,tissue engineering (TE)is one of the fast growing research fields due the accessibility of extra-molecular matrix (ECM)at cellular and molecular level with valuable potential prospective of *** enhancement in the production of hydrogel-based cellular scaffolds with the structural composition of ECM has been accelerated with involvement of rapid prototyping ***,the recreation of ECM has been derived from naturally existed or synthetic hydrogelbased *** rapid utilization of hydrogels in TE puts forward the scope of bioprinfing for the fabrication of the functional biological tissues,cartilage,skin and artificial *** main focus of the researchers is on biofabrication of the biomaterials with maintaining the biocompatibility,biodegradability and increasing growth *** this review, biological development in the structure and cross-linking connections of natural or synthetic hydrogels are *** methods and design criteria that influence the chemical and mechanical properties and interaction of seeding cells before and after the implantations are also *** methodology of bioprinting techniques along with recent development has also been *** the end,some capabilities and shortcomings are pointed out for further development of hydrogels-based scaffolds and selection of bioprinting technology depending on their application.