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991.
The crop science of Sichuan Agricultural University is an authorized first-class discipline. As the strategic supporting department for innovative talent cultivation in agriculture and forestry major, we are facing a long-term challenge in reforming the teaching mode for basic course-organic chemistry and cultivating talented students with solid basic knowledge and strong sense of innovation. Herein a thorough survey was performing to establish the executable teaching programs for this course during the "Double-First Class Universities Plan" period. A multidimensional teaching resource library for organic chemistry course was also constructed. The new classroom teaching mode "Interest cultivation-Creative thought development-Autonomous and Cooperative learning", along with a stepwise practice teaching mode "Foundation skills-Integrated application-Innovative trial" was proposed and practiced among thirty-five majors including agriculture, forestry and veterinary, to improve the quality for innovative talent cultivation and support our first-class discipline construction. This research could probably serve as a reference for congeneric agricultural university.  相似文献   
992.
以偏苯三甲酸和六水合硝酸钴为原料,通过水热法合成了2种反应时间不同的钴基金属有机聚合物(Co-MOP)。采用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)和N2吸附-脱附对Co-MOP材料进行了结构和形貌表征。将2种Co-MOP材料用作锂离子电池负极材料,并进行了电化学性能测试。结果表明,Co-MOP-12(水热反应12 h)展示出了优异的电化学性能,在100 mA·g-1的电流密度下,Co-MOP-12电极的首圈可逆比容量达到979 mAh·g-1,循环100圈后比容量高达1 345 mAh·g-1。  相似文献   
993.
Shang  Ao  Luo  Siwei  Zhang  Jianquan  Zhao  Heng  Xia  Xinxin  Pan  Mingao  Li  Chao  Chen  Yuzhong  Yi  Jicheng  Lu  Xinhui  Ma  Wei  Yan  He  Hu  Huawei 《中国科学:化学(英文版)》2022,65(9):1758-1766

Side-chain engineering has been demonstrated as an effective method for fine-tuning the optical, electrical, and morphological properties of organic semiconductors toward efficient organic solar cells (OSCs). In this work, three isomeric non-fullerene small molecule acceptors (SMAs), named BTP-4F-T2C8, BTP-4F-T2EH and BTP-4F-T3EH, with linear and branched alkyl chains substituted on the α or β positions of thiophene as the side chains, were synthesized and systematically investigated. The results demonstrate that the size and substitution position of alkyl side chains can greatly affect the electronic properties, molecular packing as well as crystallinity of the SMAs. After blending with donor polymer D18-Cl, the prominent device performance of 18.25% was achieved by the BTP-4F-T3EH-based solar cells, which is higher than those of the BTP-4F-T2EH-based (17.41%) and BTP-4F-T2C8-based (15.92%) ones. The enhanced performance of the BTP-4F-T3EH-based devices is attributed to its stronger crystallinity, higher electron mobility, suppressed biomolecular recombination, and the appropriate intermolecular interaction with the donor polymer. This work reveals that the side chain isomerization strategy can be a practical way in tuning the molecular packing and blend morphology for improving the performance of organic solar cells.

  相似文献   
994.
1,3-二羟基丙酮(DHA)是一种重要的化工原料,广泛应用于医药、化妆品及食品等领域.通过催化选择性氧化甘油制备DHA是一条高效、经济的工艺路线,而催化剂的种类及反应方式被证明对DHA的产率有较大影响.因此,结合近些年来相关文献,系统阐述了热、光和电这3种催化反应方式在甘油氧化制取DHA上的研究进展,并重点介绍了热催化路径中所选用的催化剂、相关研究实例及反应机理.最后,对甘油制备DHA的多路径选择性氧化的研究前景进行了展望.  相似文献   
995.
石墨烯的制备、功能化及在化学中的应用   总被引:2,自引:0,他引:2  
石墨烯是最近发现的一种具有二维平面结构的碳纳米材料, 它的特殊单原子层结构使其具有许多独特的物理化学性质. 有关石墨烯的基础和应用研究已成为当前的前沿和热点课题之一. 本文仅就目前石墨烯的制备方法、功能化方法以及在化学领域中的应用作一综述, 重点阐述石墨烯应用于化学修饰电极、化学电源、催化剂和药物载体以及气体传感器等方面的研究进展, 并对石墨烯在相关领域的应用前景作了展望.  相似文献   
996.
Near-infrared(NIR) fluorescent materials with high photoluminescent quantum yields(PLQYs) have wide application prospects. Therefore, we design and synthesize a D-A type NIR organic molecule, TPATHCNE, in which triphenylamine and thiophene are utilized as the donors and fumaronitrile is applied as the acceptor. We systematically investigate its molecular structure and photophysical property. TPATHCNE shows high Tgof 110℃ and Td of 385℃ and displays an aggregation-induced emission(AIE) property. A narrow optical bandgap of 1.65 eV is obtained. The non-doped film of TPATHCNE exhibits a high PLQY of 40.3% with an emission peak at 732 nm, which is among the best values of NIR emitters. When TPATHCNE is applied in organic light-emitting diode(OLED), the electroluminescent peak is located at 716 nm with a maximum external quantum efficiency of 0.83%. With the potential in cell imaging, the polystyrene maleic anhydride(PMSA) modified TPATHCNE nanoparticles(NPs) emit strong fluorescence when labeling HeLa cancer cells, suggesting that TPATHCNE can be used as a fluorescent carrier for specific staining or drug delivery for cellular imaging. TPATHCNE NPs fabricated by bovine serum protein(BSA) are cultivated with mononuclear yeast cells, and the intense intracellular red fluorescence indicates that it can be adopted as a specific stain for imaging.  相似文献   
997.
Wacker oxidation is an industry-adopted process to transform olefins into value-added epoxides and carbonyls. However, traditional Wacker oxidation involves the use of homogeneous palladium and copper catalysts for the olefin addition and reductive elimination. Here, we demonstrated an ultrahigh loading Cu single atom catalyst(14% Cu, mass fraction) for the palladium-free Wacker oxidation of 4-vinylanisole into the corresponding ketone with N-methylhydroxylamine hydrochloride as an additive under mild conditions. Mechanistic studies by 18O and deuterium isotope labelling revealed a hydrogen shift mechanism in this palladium-free process using N-methylhydroxylamine hydrochloride as the oxygen source. The reaction scope can be further extended to Kucherov oxidation. Our study paves the way to replace noble metal catalysts in the traditional homogeneous processes with single atom catalysts.  相似文献   
998.
The Bcl-2 family small molecule inhibitor navitoclax is being clinically evaluated to treat multiple cancers including lymphoid malignancies and small cell lung cancer. A sensitive and reliable method was developed to quantitate navitoclax in human plasma using liquid chromatography with tandem mass spectrometry with which to perform detailed pharmacokinetic studies. Sample preparation involved protein precipitation using acetonitrile. Separation of navitoclax and the internal standard, navitoclax-d8, was achieved with a Waters Acquity UPLC BEH C18 column using isocratic flow over a 3 min total analytical run time. A SCIEX 4500 triple quadrupole mass spectrometer operated in positive electrospray ionization mode was used for the detection of navitoclax. The assay range was 5–5,000 ng/ml and proved to be accurate (89.5–104.9%) and precise (CV ≤ 11%). Long-term frozen plasma stability for navitoclax at −70°C was at least 43 months. The method was applied for the measurement of total plasma concentration of navitoclax in a patient receiving a 250 mg daily oral dose.  相似文献   
999.
CuSe2微纳米晶具有独特的光电特性而受到广泛关注.本文通过微波辅助多元醇介种生长法控制一系列条件制备出十四面体的CuSe2微纳米晶,并研究其生长过程以及电极反应过程动力学.产物制备结果表明:PVP的用量,TETA的用量,反应温度均对CuSe2微纳米晶的形貌有显著的影响;电化学结果表明:CuSe2电极在Na2SO4溶液...  相似文献   
1000.
Molybdenum(VI) bis(imido) complexes [Mo(NtBu)2(LR)2] (R=H 1 a ; R=CF3 1 b ) combined with B(C6F5)3 ( 1 a /B(C6F5)3, 1 b /B(C6F5)3) exhibit a frustrated Lewis pair (FLP) character that can heterolytically split H−H, Si−H and O−H bonds. Cleavage of H2 and Et3SiH affords ion pairs [Mo(NtBu)(NHtBu)(LR)2][HB(C6F5)3] (R=H 2 a ; R=CF3 2 b ) composed of a Mo(VI) amido imido cation and a hydridoborate anion, while reaction with H2O leads to [Mo(NtBu)(NHtBu)(LR)2][(HO)B(C6F5)3] (R=H 3 a ; R=CF3 3 b ). Ion pairs 2 a and 2 b are catalysts for the hydrosilylation of aldehydes with triethylsilane, with 2 b being more active than 2 a . Mechanistic elucidation revealed insertion of the aldehyde into the B−H bond of [HB(C6F5)3]. We were able to isolate and fully characterize, including by single-crystal X-ray diffraction analysis, the inserted products Mo(NtBu)(NHtBu)(LR)2][{PhCH2O}B(C6F5)3] (R=H 4 a ; R=CF3 4 b ). Catalysis occurs at [HB(C6F5)3] while [Mo(NtBu)(NHtBu)(LR)2]+ (R=H or CF3) act as the cationic counterions. However, the striking difference in reactivity gives ample evidence that molybdenum cations behave as weakly coordinating cations (WCC).  相似文献   
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