Interfacial solar steam generation is emerging as a promising high-efficiency strategy to produce clean water by harvesting and converting clean solar energy into localized heat. Here, we demonstrate a facile and effective approach to improve the photothermal performance by combining porous Ni mesh and carbon nanotube (CNTs) to construct an all-in-one Ni/CNTs solar absorber. In this work, due to the multiple reflections of incident light inside Ni/CNTs and the electronic transitions in the molecule, the Ni/CNTs solar absorber can efficiently utilize solar energy (94.3%) with an excellent evaporation rate of 2.13 kg m(-2) h(-1) under one sun illumination. The interfacial solar evaporator based on the Ni/CNTs solar absorber effectively removed heavy metal ions and dye molecules from contaminated water and displayed stable rate (1.96 kg m(-2) h(-1)) for 46 h of cyclic evaporation, showing its great potential for practical seawater desalination.

通过有限元分析,利用COMSOL软件模拟计算了Nano-LED半极性面InGaN/GaN单量子阱距离边缘不同位置的应变和压电极化分布,并结合模拟得到的量子阱极化电场,采用Silvaco软件计算得到了Nano-LED InGaN/GaN单量子阱距离边缘不同位置的发光光谱。应变和压电极化分布结果表明,其在距离半极性面量子阱边缘100 nm的范围内变化明显。然而,在半极性面内部,应力释放现象消失,压电极化电场变强,量子限制Stark效应导致InGaN/GaN单量子阱发光强度降低。发光光谱分析表明,60 mA工作电流下,Nano-LEDInGaN/GaN半极性面量子阱边缘位置的光谱峰值最大蓝移达21 nm,其原因在于边缘的应力释放作用。Nano-LED非极性面和半极性面的整体光谱分析表明,在固定Nano-LED高度条件下,Nano-LED的直径越大,半极性面占比越高,器件整体发光光谱的双峰值现象越明显,这将为多波长Nano-LED器件的设计提供借鉴。

Covalent organic framework (COFs) and conjugated microporous polymers (CMPs) adopt rigid structure directing motifs as building blocks, which are connected by covalent bonds in a specific polymerization reaction with crystalline and amorphous morphology, respectively. They usually possess high specific surface area, controllable porous structure, as well as physical and chemical stability. Due to the diversity of organic monomers and organic reactions, COFs and CMPs can be synthesized by designing suitable monomers and organic polymerization reactions for specific applications. In recent years, COFs and CMPs as functional materials have received extensive attention, and great progress have been made in electrochemical energy storage and conversion. In this review, we systematically sorted out the design principles of COFs and CMPs as lithium-ion batteries (LIBs) and supercapacitors (SC) electrode materials, as well as water-splitting electrocatalysts. Subsequently, the latest advances in COFs and CMPs for energy storage and conversion systems were introduced from the perspective of synthesis strategies. Finally, we put forward the outlook and prospects of COFs and CMPs for LIBs, supercapacitors, hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) with high-efficiency. (C) 2021 Elsevier B.V. All rights reserved.

根据红外焦平面读出电路输出缓冲器的大输出摆幅和大压摆率的特点,设计了一种应用于红外焦平面读出电路的新型输出缓冲器,由于输出缓冲器需要一个较大的输出摆幅,所以采用轨对轨输入以及AB类输出的全差分运放,使其在不损失增益的情况下提高带宽和输出摆幅;并在轨对轨结构中插入恒定跨导电路,使电路更加稳定;在输出缓冲器高压摆率的要求下,输出级插入压摆率提高电路,使电路达到更好的性能.该输出缓冲器采用TSMC 0.18 μm CMOS工艺,50 pF电容负载、100 kΩ电阻负载,5 V工作电压.仿真结果表明,在输入摆幅1～4.8 V的情况下输出摆幅能到达1～4.8 V,增益能达到100.34 dB,带宽为58 MHz,正负压摆率分别为89 V/μs、-92 V/μs,其他仿真结果也均满足缓冲器的设计要求.

随着资源的枯竭以及环境问题的日益严峻,可再生绿色资源的高值化利用日益受到重视。乙酰丙酸作为一种新一代生物质基绿色平台化合物,可用来制备燃料和高附加值的化学品。笔者详细介绍了木质纤维生物质制备乙酰丙酸的最新研究进展,重点介绍了乙酰丙酸的两条重要制备路径和各种催化体系的制备方法以及乙酰丙酸的应用。生产乙酰丙酸最原始的方法是在水溶液中进行。虽然液体酸制备乙酰丙酸具有反应效率高、反应时间短等优点,但也存在一些缺点,比如酸回收成本高、乙酰丙酸分离困难、对设备的要求高等,而固体酸的应用很好地克服了以上问题。固体酸催化剂制备过程需要考虑的是强酸位点的数量和酸位点的类型,这是生成目标化学品乙酰丙酸的关键因素。离子液体和γ-戊内酯作为绿色溶剂,也应用于乙酰丙酸的生产。此外,还对乙酰丙酸的衍生物5-氨基乙酰丙酸、γ-戊内酯和2-甲基四氢呋喃作了详细描述。最后分析了乙酰丙酸制备面临的可能挑战,提出了未来的研究方向,以期为广大研究者提供有益参考。

γ?戊内酯是以木质纤维素生物质为原料制备的一种潜力巨大的平台化合物,它既可转化为高密度燃料、相关高分子材料以及其他高价值化学品,也可作为绿色溶剂促进木质生物质向其他高值方向转化.在化石能源日益紧俏、环境问题日益严重的今天,对γ?戊内酯进行深入研究显得尤为重要.但在实际生产中,仍存在产量低、除杂难等经济环保类问题需要解决.基于γ?戊内酯研究的最新进展,从γ?戊内酯的制备与应用两方面进行了论述,综述了生物质催化生产γ?戊内酯的研究进展,说明不同底物生产γ?戊内酯的理论基础与优缺点,并以贵金属和非贵金属催化剂为界,分类讨论了多种用于合成γ?戊内酯的催化剂.最后,结合γ?戊内酯在纤维素生物质转化应用方面的进展情况,探索了γ?戊内酯与其他相关有机物之间的制备关系,为γ?戊内酯的进一步开发利用提供了思路.

非金属矿物是我国造纸工业中重要的填料和颜料,目前应用在造纸领域的已有约50余种,其中碳酸钙、高岭土、滑石、硅灰石、膨润土和硅藻土最为常见.随着我国造纸产业的发展,对于造纸用非金属矿物粉体的功能特性要求也越来越高,需要在传统矿物属性的基础上进行改性处理,以赋予矿物粉体更多新的性能.围绕6种造纸用非金属矿物,对已有研究进行了综述,旨在为推动我国造纸产业高质量发展和非金属矿物高效利用提供新的思路.

The research progress on each functional layer material of quantum dot light emitting diodes (QLEDs) fabricated by the spin-coating method are reviewed.The characteristics and applications of various materials for carrier injection layers and transport layers prepared by spincoating are compared and summarized.Numerous studies show that the inorganic metal oxide materials (ZnO,TiO2,etc) are superior to organic materials in the electron mobility and device reliability as the electron transport layer (ETL),and the organic polymer materials (poly [double (4-phenyl) (4-butyl phenyl) amine] (Poly-TPD),poly (9-vinyl carbazole) (PVK),etc) with higher hole mobility and better film quality are more widely used as the hole transport layer (HTL).Moreover,a few inorganic metal oxide materials such as MoOx and WOx,etc are widely used as the hole injection layer due to their better energy level matching and higher reliability.With the technology maturity and the demands of higher efficiency and higher reliability in QLEDs applications,inorganic metal oxide materials prepared by low-cost spin-coating method will become more and more widespread,which will promote the commercialization of QLEDs.

The photo-instability and degradation of colloidal quantum dots (QDs) are major challenges in their applications.We report photo-stability enhancement of colloidal CdSe/ZnS QDs passivated in SiO2 thin film deposited by RF magnetron sputtering.First,the red (615 nm emission) CdSe/ZnS QDs were synthesized by tri-n-octylphosphine assisted successive ionic layer adsorption and reaction method.The QDs were then spin-coated to the SiO2/Si substrate,and a SiO2 film with a thickness of 20 nm was deposited on the QDs as a passivation layer by magnetron sputtering.The photoluminescence spectra of passivated and un-passivated QDs were investigated by using a continuous wave laser source,which was irradiated in air and vacuum respectively.The results show that the PL intensity of the QDs without SiO2 passivation decreases significantly,and the PL peak shifts to blue and the FWHM increases continuously with the increasing of the irradiation time.Comparative analysis shows that SiO2 film can prevent the oxidation of QD surface from water vapor and oxygen molecules and thus the stability of CdSe/ZnS QDs is significantly improved.

In order to realize the preparation of large-area periodic micro-nano structures to enhance the luminous efficiency of LEDs, Lloyd laser interference lithography (LIL) system was established.The working principle of LIL system was simply analyzed and the experimental process of preparing the one-dimensional gratings, two-dimensional lattice and hole arrays was introduced.Finally, the nano-structures were transferred into suitable functional substrates for further applications.The experimental results indicate that the uniform gratings or two-dimensional lattice arrays structures with the period of 450 nm, whose duty cycle can also be changed, are successfully fabricated on 20 mm×20 mm ITO substrates by using the LIL system.

The purpose of this study is to investigate the differences in physical and chemical characteristics of soybean sprouting at different time and provide theoretical bases for edible and processing use of sprouting soybean.Seven soybean materials with different sprouting periods were used to measure the length of sprouts,the contents of protein,total sugar,fat,ash,reducing sugar,vitamin C,calcium,magnesium,iron,manganese,copper and zinc by using conventional chemical methods and the atomic absorption spectroscopy analysis (AAS).The relationships between sprout time and quality characters were analyzed by principal component analysis (PCA) and hierarchical cluster analysis (HCA).The results showed that there was a certain correlation between most nutrient quality characters.The cumulative variance contribution of two extracted principal components was 92.18％ approximately.The first principal component was related to length of sprouts,fat,ash,reducing sugar,vitamin C,calcium,magnesium and iron contents,which were the basic quality factors.The second principal component was related to protein and total sugar contents,which were the feature factors.Based on the component score plots and cluster analysis,the seven kinds of soybean were classified into three groups.The first group was rich in basic nutrition,the second group had higher sugar and lower protein,and the third group was related to higher protein,higher vitamin C and lower sugar content.These results preliminarily made sure the nutrition characteristics of soybean sprouts germinated at different time,and could provide references for direct eating and further processing of soybean sprouts.

汽车车灯为汽车行驶必不可少的安全部件，在汽车主动安全方面的作用至关重要。80年代后期伴随高亮度发光二级管技术的出现，LED在汽车外部照明的应用成为可能。 LED可靠性强、使用寿命长、色纯度高、响应速度快、体积小便于设计等优点，使其在车外照明方面得到越来越普遍的应用。进入21世纪，LED 车灯已经成为汽车潮流的新宠，被广泛应用于转向灯、制动灯、前照灯等信号灯具上。本产品是基于研究高亮度LED汽车灯驱动与控制电路的基础上，实现基于LED汽车灯的车联网系统，实现相邻行车之间通过车灯进行光通信，在前后车辆间传递车辆状态、前方路况、语音等信息。

Ribbon-like ultramicroporous conjugated polycarbazole network P-TCzTAT was synthesized having high BET surface area and narrow pore width distribution.

通过对不同研磨时间磷块岩样品的粒度、比表面积、XRD分析、SEM分析以及元素溶出性能的测试,系统的研究了湿法研磨时磷块岩的机械力化学效应.结果表明:在湿法超细研磨体系中,研磨时间的增加可以显著降低磷块岩颗粒粒径、增大比表面积、改善矿粉表面形貌并提高品格结构无序化程度.这些物理性质的改变促进了磷块岩中P、Ca和Mg元素的溶出,在研磨25h时,3种元素释放量最大,分别为28.51、24.65和10.04g/kg.

介绍了静止无功补偿器(STATCOM)的结构和原理,研究了STATCOM中换流链的瞬时功率特性,并求得了换流链的充放电功率的解析表达式.提出换流链的等效充放电电路,并根据换流链的瞬时功率,忽略掉电容电压的波动分量,求得换流链的充放电电流,进而求出电容电压的解析表达式.根据电容电压的解析表达式,同时考虑到STATCOM的过压和过流倍数,推导出子模块电容的设计方程;根据实际工程参数设计了子模块的电容.电容电压的计算波形、仿真波形和实际波形的对比说明了电容电压解析表达式的正确性,电容的设计方法能够满足工程需要.

The bias-enhanced performance of visible-blind ultraviolet (UV) detection of GaN Schottky barrier diodes has been studied. The UV response of the Schottky diodes was found to be vastly amplified at elevated reverse bias, leading to the observation of the voltage-dependent gain arising from the defect-induced Schottky barrier lowering effect. In contrast, the visible light response of the GaN Schottky diodes shows insignificant voltage dependence because of the dominance of the internal photoemission absorption. Thus, the visible rejection ratio, defined as the responsivity of UV over visible range, can be greatly enhanced at high operating bias for the UV detectors based on the GaN Schottky barrier diodes. The observation has been supported by both experimental results and simulation data, and has been utilized to minimize the interference between the monolithically integrated GaN photodetectors and power light-emitting diodes (LEDs) in the present study of LED communication.

A solution-processed acceptor-π-donor-π-acceptor (A-π-D-π-A) type small molecule, namely DCATT, has been designed and synthesized for the application as donor material in organic solar cells. The fused aromatic unit thieno[3,2-b]thiophene (TT) flanked with thiophene is applied as π bridge, while 4,8-bisthienyl substituted benzodithiophene (BDT) and 2-ethylhexyl cyanoacetate are chosen as the central building block and end group, respectively. Introduction of fused ring to the small molecule enhances the conjugation length of the main chain, and gives a strong tendency to form π-π stacking with a large overlapping area which favors to high charge carrier transport. Small-molecule organic solar cells based on blends of DCATT and fullerene acceptor exhibit power conversion efficiencies as high as 5.20 % under the illumination of AM 1.5G, 100 mW cm(-2) .

采用CdSe/ZnS红光量子点(QD),利用旋涂和真空蒸镀工艺制备了结构为ITO/TPD+PVK/QDs/Alq3/LiF/Al的量子点发光器件(QD-LED),并对器件的发光性能做了测试.研究了ITO表面处理、TPD空穴传输层和QD发光层的厚度对QD-LED性能的影响,并通过调整QD发光层和Alq3电子传输层的厚度,制备了可用于照明的白光QD-LED.实验结果表明,ITO的表面处理可有效降低器件的开启电压,开启电压从9V降到7V左右;TPD空穴传输层和QD发光层的厚度对器件的电流密度和发光亮度有较大的影响,而Alq3电子传输层和QD发光层的合理配比可以混合出较高色温的白光.通过优化器件各参数,当TPD和PVK质量比为5∶1、QD度为1.0 mg/ml和Alq3厚为60 nm时,制备的器件在15V电压时发光效率达到了1 500 cd/m2,色坐标为(0.362 8,0.3796),显色指数为88.1.

The enantioselective alpha-chlorination of cyclic beta-ketoesters catalyzed by chiral 2-aminoalcohol derivatives (2t) has been developed. For the optically active a-chlorinated products, the isolated yields are in the range of 85-94% and the enantiomeric excesses are up to 84% ee.

表面等离子体能够增强氮化镓发光二极管的发光效率,为高效发光二极管芯片的研究提供了可行的方案.近年来,国内外研究小组在利用表面等离子体增强氮化镓发光二极管发光效率的实验中,取得了很多有价值的结果.介绍了具有金属薄膜、金属颗粒和金属光子晶体等典型结构的氮化镓发光二极管.重点探讨了表面等离子体增强发光二极管发光的机理、结构和关键技术.对具有二维金属光子晶体的氮化镓发光二极管发光增强机理进行了分析和预测,认为利用二维光子晶体可以从内量子效率和外量子效率两方面增强器件发光,并且有很好的可控制性,是提高发光效率的可行方案.