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961.
樊良鑫  何方雨  史力军  李晓  徐翠莲 《化学通报》2022,85(9):1077-1082,1089
吲唑酮作为氮杂环分子当中的重要一员,其分子骨架不仅是有机合成当中的重要中间体,还是许多天然产物和药物分子的核心结构。因此,该类化合物的高效合成一直是合成化学家们的研究热点。本文综述了近二十年来利用过渡金属、高价碘、酸、碱、光、过氧化物以及付-克环化等方法合成吲唑酮骨架的研究进展并展望了吲唑酮化合物合成的研究方向和应用前景  相似文献   
962.
Fu  Enfa  Zhang  Sijia  Luan  Yu  Zhang  Yuting  Saghir  Summaira  Xiao  Zhenggang 《Cellulose (London, England)》2022,29(3):1727-1737
Cellulose - Most superabsorbent polymers (SAPs) are prepared based on synthetic polymers (from petroleum resources), making them costly, nondegradable, and not ecofriendly. To overcome these...  相似文献   
963.
杨霄  万译文  黄华伟  索纹纹  肖维  李小玲 《色谱》2022,40(7):625-633
建立了分散固相萃取-超高效液相色谱-串联质谱法同时测定水产品中5种硝基咪唑类和6种苯二氮卓类药物残留的方法。样品用1%(v/v)氨水乙腈提取,提取液经十八烷基键合硅胶(C18)和N-丙基乙二胺(PSA)吸附剂净化,在45℃下用氮气吹至近干,用1 mL甲醇-水(1∶9,v/v)溶液复溶,过0.22μm尼龙-66滤膜后用超高效液相色谱-串联质谱测定。目标化合物采用Kinetex F5色谱柱(100 mm×3.0 mm,2.6μm)分离,以0.1%(v/v)甲酸水溶液和甲醇作为流动相进行梯度洗脱,在电喷雾离子源(ESI)、正离子扫描和多反应监测(MRM)模式下进行测定,基质匹配外标法定量。结果表明,5种硝基咪唑类和6种苯二氮卓类药物在8.5 min内完成色谱分离分析,目标物在0.5~20μg/L范围内线性关系良好,相关系数均大于0.995,检出限和定量限分别为0.2~0.5μg/kg和0.5~1.0μg/kg。以草鱼、对虾和大黄鱼为样品基质,在3个不同的添加水平下,5种硝基咪唑类和6种苯二氮卓类药物的平均回收率为73.2%~110.6%,相对标准偏差(RSD)小于15%。本研究建立的方法具有简单、快速、灵敏度高和成本低等优势,可用于水产品中5种硝基咪唑类和6种苯二氮卓类药物的快速检测。该方法的建立为我国水产品质量安全相关监管部门同时监控水产品中硝基咪唑类和苯二氮卓类药物残留提供了技术支持。  相似文献   
964.
吉林大学应用化学学科始建于1986年,依托吉林大学化学学科深厚理论基础与学术优势,经过几代应用化学学科人的不懈努力,逐渐形成了“理工兼备”的学科特色。在吉林大学化学学科70华诞之际,回顾了应用化学学科的发展历程,着重介绍了应用化学学科在本科教学与专业特色、科学研究与平台建设、人才培养与社会服务等3个方面取得的成绩,以及今后发展的设想。  相似文献   
965.
966.
The purpose of this paper is to fabricate novel nanoparticles (NPs) from a single disulfide bond-bridged block copolymer poly(hydroxyethyl methacrylate)-S-S-polycaprolactone (PHEMA-S-S-PCL). The novel biomaterial was synthesized by ring-opening polymerization and reversible addition–fragmentation chain transfer polymerization. The cargo-free NPs were fabricated with the solvent evaporation method, and studies on NPs' characterizations were carried out. The hydrogen nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy spectra confirmed the synthesis of PHEMA-S-S-PCL copolymer. Thermo-gravimetric analysis curves indicated that the obtained PHEMA-S-S-PCL copolymer had good thermostability. Transmission electron microscopy and dynamic light scatter results suggested that the cargo-free NPs were in round shapes with an average diameter of 103.6 ± 0.12 nm. The low critical micelle concentration of cargo-free NPs (7.9 × 10?4 mg/ml) indicated that these NPs would keep their spherical shapes after being attenuated by abundant liquid (e.g., blood or body fluid). Furthermore, these NPs showed high stability at the presence of bovine serum albumin. Therefore, it could be speculated that these NPs would not be absorbed by proteins in blood, and they could be used as a candidate carrier for drug delivery.  相似文献   
967.
Adding insulating polymers to conjugated polymers is an efficient strategy to tailor their mechanical properties for flexible organic electronics. In this work, we selected two insulating polymers as additives for high-performance photoactive layers and investigated the mechanical and photovoltaic properties in organic solar cells (OSCs). The insulating polymers were found to reduce the electron mobilities in the photoactive layers, and hence the power conversion efficiencies were significantly decreased. More importantly, we found that the insulating polymers exhibited negative effect on the mechanical properties of the photoactive layers, with reduced Young's modulus and low crack onset strains. Further studies revealed that the insulating polymers had poor miscibility with the photoactive layers, providing large domains and more cavities in blend thin films, which act as negative effect for the tensile test. The studies indicate that rational selection of insulating polymers, especially enhancing the non-covalent interaction with the photoactive layers, will be critically important for the stretchable OSCs.  相似文献   
968.
Zheng  Ming  Gao  Bing  Tang  Suwen  Zhu  Min  Tang  Liang  Wu  Minghong 《Catalysis Surveys from Asia》2022,26(3):174-182

Zinc molybdate (ZnMoO4), a layer perovskite material, has the advantages of high stability, excellent optical and charge properties. However, its high band gap and high electron–hole recombination efficiency limit its application in the photocatalytic reduction field like hydrogen production. In this study, we used CdS as a co-catalyst and successfully prepared CdS/ZnMoO4 composite photocatalysts with different loadings. The hydrogen evolution rate of CdS/ZnMoO4 reached 530.2 µmol h?1 g?1, which was approximately 11 and 100 times more than rates of pure CdS and ZnMoO4 under the same conditions, respectively. It is the presence of CdS that contributed to this improved performance, which acted as an electron acceptor to separate electrons and holes. Besides, a reasonable mechanism was provided based on photoelectrochemical characterizations. CdS loading greatly improved the hydrogen evolution performance of ZnMoO4 under visible light, providing a direction to improving the performance of perovskite based photocatalysts.

  相似文献   
969.
Electrochemical reduction of carbon dioxide into value-added products is a promising way to recycle the greenhouse gas, thus solving the crisis of global warming. Pressing challenges remain in regulating the catalytic selectivity. In this work, we demonstrated a metal-organic frameworks-assisted approach to synthesizing In species loaded on the surface of N doped carbon matrix. By controlling the particle sizes, the catalytic selectivity can be easily altered. The obtained Inc/NC possesses the outstanding capability for converting CO2 into CO. And 80.09% Faraday efficiency (FE) of CO can be achieved at 0.8 V vs. RHE. While the In2O3/C exhibits different catalytic behaviors, the main product is formic acid and the FE is more than 50% at 0.8 V vs. RHE. The selectivity reversal can be attributed to the strong interactions between In clusters and N atoms of carbon supports, which efficiently inhibits the formation of the by-product, formic acid. Our research has paved a new way to modulate catalytic selectivity by manipulating the fine structures of the catalysts.  相似文献   
970.
Two-dimensional covalent organic frameworks(2D COFs)bearing various topologies can be precisely designed based on the symmetry of monomers.Their pore environment can be further regulated via either pre-functionalization of the monomers or post-modification of the skeleton.Among them,sub-stoichiometric synthesis is an efficient method which can mediate uncondensed functional moieties periodically arranged in the COF skeletons.Herein,a series of imine-linked 2D COFs with specifically decorated formyl or amino groups were selectively synthesized via sub-stoichiometric formyl transamination.The molar ratios of the monomers directly determine the structures of the resulting COFs with periodic vertex vacancies.The COF with polar amino sites could efficiently capture CO2 and H2O.This work demonstrates tuning the stoichiometry of the monomers could facilely modulate the functions of the pore channels.It also provides insights into constructing novel COFs with complex structures for targeted applications.  相似文献   
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