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1.
Alkenyl boron-esters and acrylonitrile groups are key structural functional groups found in dyes, pesticides, fluorescent compounds, functional materials, and biologically active drugs. Considerable efforts have been devoted for the introduction of boron-esters and acrylonitrile groups by using alkenes and alkynes conversion routes for boronation, hydroboronation, dehydrogenative boronation, cyanation, hydrocyanation, alkylcyanation, cyanomethylation. These reported methodologies are very valuable for the industrial production of acrylonitriles and alkenyl boron esters.  相似文献   
2.
近年来,设计和合成高性能非富勒烯受体(NFAs)材料已经成为太阳能电池研究领域的前沿课题。基于DA'D型稠环结构的NFAs由于具有吸光系数高、能级和带隙可调、结构易于修饰、分子可高效合成、光电学性能优异等优点而受到了越来越广泛的关注。在短短7年的时间里,能量转换效率(PCE)从3%~4%提高到18%。2019年初邹应萍等报道了一个优秀的受体分子Y6,与PM6共混制备单结电池,获得了15.7%的能量转换效率。Y6类受体材料的中心给电子单元为DA'D型稠环结构,缺电子单元(A')通过氮原子与两个给电子单元(D)并联形成稠环结构,这有助于降低前线分子轨道能级并增强吸收,同时与氮相连的两个烷基链和位于噻吩并噻吩β位的两个侧链则有助于提高溶解度及调节结晶性。自Y6问世以来,人们对分子的结构剪裁进行了深入的研究,并报道了数十种新的结构。在这些新的受体中,DA'D部分的结构裁剪对提高器件效率和太阳能电池的性能起着至关重要的作用。本文对A'、D单元和侧链结构修饰的研究进展进行了综述。通过选择几组受体,对最近报道的分子进行分类,并将它们的光学、电化学、电学和光电性质与精确的结构修饰相关联,从而对结构-性能关系进行全面概述。  相似文献   
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4.
The contribution of electrospun nanofibrous membranes (e.NFMs) in the biosensing platforms opens up a new prospect for the invention of faster and more sensitive analytical devices. In this paper, we utilized e.NFM of polyethersulfone (PES) as a solid substrate for the protein immobilization through two different approaches: physical and covalent. Scanning electron microscopy (SEM) and Fourier‐transform‐infrared (FTIR) tests were performed to study the effect of plasma treatment on protein immobilization efficacy. Moreover, taking advantage of ELISA technique, the influence of different parameters, namely, nanofibers diameter, membrane thickness, plasma treatment time, an incubation time of ethyl‐3‐(3‐dimethylaminopropyl)‐carbodiimide/N‐hydroxysuccinimide (EDC/NHS), and their ratio on antibody immobilization efficacy through two mentioned approaches, was also assessed.  相似文献   
5.
在管式反应器中采用苯甲酸、聚乙二醇、固体古马隆树脂(S)、液体古马隆树脂(L)为添加剂来降低煤沥青中有害物质苯并芘的含量,以期使得煤沥青可绿色化应用。采用紫外-可见分光光度计分析煤沥青中苯并芘含量。考察了反应温度、反应时间、添加剂添加量、催化剂等工艺条件对添加剂脱除煤沥青中苯并芘的影响。结果表明,不同工艺条件能降低煤沥青中苯并芘的含量。在优化条件下,不同添加剂对苯并芘脱除率由高到低依次为:液体古马隆树脂、聚乙二醇、苯甲酸和固体古马隆树脂。分析其反应机理,这与催化剂的酸性相关,发生亲电取代反应。结果表明,液体古马隆树脂(L)在催化剂存在下对煤沥青中苯并芘脱除率可达73.0%,显示了良好的应用前景。  相似文献   
6.
A bisphenol bearing pendant maleimide group, namely, N‐maleimidoethyl‐3, 3‐bis(4‐hydroxyphenyl)‐1‐isobenzopyrrolidone (PPH‐MA) was synthesized starting from phenolphthalein. Aromatic (co)polyesters bearing pendant maleimide groups were synthesized from PPH‐MA and aromatic diacid chlorides, namely, isophthaloyl chloride (IPC), terephthaloyl chloride (TPC), and 50:50 mol % mixture of IPC and TPC by low temperature solution polycondensation technique. Copolyesters were also synthesized by polycondensation of different molar proportions of PPH‐MA and bisphenol A with IPC. Inherent viscosities and number‐average molecular weights of aromatic (co)polyesters were in the range of 0.52–0.97 dL/g and 20,200–32,800 g/mol, respectively indicating formation of medium to reasonably high‐molecular‐weight polymers. 13C NMR spectral analysis of copolyesters revealed the formation of random copolymers. The 10% weight loss temperature of (co)polyesters was found in the range 470–484 °C, indicating their good thermal stability. A selected aromatic polyester bearing pendant maleimide groups was chemically modified via thiol‐maleimide Michael addition reaction with two representative thiol compounds, namely, 4‐chlorothiophenol and 1‐adamantanethiol to yield post‐modified polymers in a quantitative manner. Additionally, it was demonstrated that polyester containing pendant maleimide groups could be used to form insoluble crosslinked gel in the presence of a multifunctional thiol crosslinker. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 630–640  相似文献   
7.
The biodegradability of phtalic acid esters in marine and freshwater environments was characterized by their binding free energy with corresponding degrading enzymes. According to comprehensive biodegradation effects weights, the binding free energy values were converted into dimensionless efficacy coefficient using ratio normalization method. Then, considering comprehensive dual biodegradation effects value and the structural parameters of PAEs in both marine and freshwater environments, a 3D-QSAR pharmacophore model was constructed, five PAE derivatives (DBP−COOH, DBP−CHO, DBP−OH, DINP−NH2, and DINP−NO2) were screened out based on their environmental friendliness, functionality and stability. The prediction of biodegradation effects on five PAE derivatives by biodegradation models in marine and freshwater environment increased by 15.90 %, 15.84 %, 27.21 %, 12.33 %, and 8.32 %, and 21.57 %, 15.21 %, 20.99 %, 15.10 %, and 9.74 %, respectively. By simulating the photodegradation path of the PAE derivative molecular, it was found that DBP−OH can generate .OH and provides free radicals for the photodegradation of microplastics in the environment.  相似文献   
8.
随着光学测量与遥感领域的不断发展,折反式光学系统对重量、体积和环境适应性等需求不断提高。基于增材制造技术的金属反射镜以其便于实现优化设计、快速制造和加工工艺性好等优点,逐渐获得国内外学者的关注与研究。与传统金属反射镜相比,增材制造金属反射镜可以提高反射镜的结构刚度,同时可实现更高程度的轻量化。增材制造反射镜可以满足光学系统对环境适应性和快速性的需求。本文首先讨论了金属反射镜的评价指标;其次,综述了国内外在基于增材制造技术制备金属反射镜领域的发展现状和技术参数,从增材制造金属反射镜的基体设计与制备和基体的后处理2个方面展开论述;然后,通过分析,总结了增材制造金属反射镜的技术路线和关键技术;最后,对增材制造反射镜的应用前景提出了展望。  相似文献   
9.
《Comptes Rendus Chimie》2015,18(6):619-625
A new terdentate acyclic pincer ligand, 2,6-bis(tert-butylthiomethyl)pyridine (tbtmp), was synthesized and reacted with several complexes of iron, zinc, nickel, cobalt, and copper. The ligand and its coordination compounds were characterized using elemental analysis, infrared, 1H- and 13C-NMR-spectroscopy, thermal analyses, plus—for the Zn complex—single-crystal X-ray diffractometry. The structure of [Zn(L)Br2] was solved in the tetragonal crystal system, chiral space groups P41212 and P43212 (No. 92 and No. 96, a = 947.2(1) pm, c = 2265.2(5) pm), revealing five-fold coordination of the metal atoms. According to spectroscopy, all complexes share the same coordination environment around the metal atoms, consisting of two halide anions and a sulfur-methylene-pyridine-methylene-sulfur entity; tbtmp acts as a tridentate ligand with the pyridine N atom and both tert-butylthio S atoms coordinating to the metal ions (NS2). The analysis results indicate that the metal ions are coordinated as distorted pseudo-bipyramids, LMX2, with the chelate ligand meridionally arranged. One of the complexes contains ethanol as an additional ligand, resulting in a pseudo-octahedral coordination sphere [Ni(L)Cl2EtOH]. The latter was obtained in the form of green crystals, which turn into a red powder with loss of the ethanol molecule. Fe (III), Co(II), Ni(II) and Cu(II) metal complexes [M(L)Cl2] were screened for their antibacterial activity against B. subtilis G(+) and Escherichia coli G(−) bacteria, and fungus (Candida albicans and Aspergillus flavus).  相似文献   
10.
The surface grafting of attapulgite (ATP) with polystyrene (PS) was established via a simultaneous reverse and normal initiation atom transfer radical polymerization (SR&NIATRP). 4‐(chloromethyl)phenyltrimethoxysilane (CMPTMS) chemical bounded on the surface of ATP (ATP‐Cl, Cl‐I) was prepared via one‐step self‐assembly. SR&NI ATRP of styrene was conducted using CuCl2 complex tris(2‐(dimethylamino)ethyl)amine (Me6‐TREN) as the catalytic system, initiated by 2,2‐azobis(isobutyronitrile) (AIBN) and ATP‐Cl. FT‐IR, XRD, XPS, TGA and TEM data were consistent with the grafting of benzyl chloride groups and PS chains on ATP surface. The controllability of polymerization was investigated by the kinetics behavior under different molar ratio of AIBN and CuCl2. The obtained polymer possessed a uniform distribution of molecular weights with a lower polydispersity index of 1.2~1.4. The relationship between polymerization on the surface of ATP and in solution was discussed in detail based on TGA data of hybrid particles and GPC trace of free polymer in solution. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1508–1516  相似文献   
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