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951.
The Role of Processing Solvent on Morphology Optimization for Slot-Die Printed Organic Photovoltaics
Wang Lei Zhan Jun-Zhe Zhong Wen-Kai Zhu Lei Zhou Guan-Qing Hao Tian-Yu Zou Ye-Cheng Wang Zhen-Hua Wei Gang Zhang Yong-Ming Liu Feng 《高分子科学》2023,41(6):842-850
Chinese Journal of Polymer Science - The morphology manipulation of the active layers is important for improving the performance of organic photovoltaics (OPVs). The choice of processing solvent... 相似文献
952.
采用Rajagopal和Wineman所提出本构方程,对电流变液在二维平行平板间非零压力梯度Couette流动的线性稳定性问题进行研究.通过分析和数值计算发现,任何壁面运动都将使流动稳定性增强.在外加电场存在的情况下,电流变液效应也将使流动稳定性增强. 相似文献
953.
[reaction: see text]. Protein and peptide conjugates such as glycopeptides, prenylated peptides, and lipopeptides play essential roles in biology. A rapid and convergent entry into a variety of these compounds is described. The methodology involves the introduction of a dehydroalanine into peptides and subsequent chemoselective conjugate addition of an appropriate thiolate nucleophile, including farnesylthiolate or thioglycosides. 相似文献
954.
Polynuclear Pd(II) and Ni(II) complexes of macrocyclic polyamine 3,6,9,16,19,22‐hexaazatricyclo[22.2.2.211,14]‐triaconta 11,13,24,26(l),27,29‐hexaene (L) in solution were investigated by electrospray ionization mass spectrometry (ESIMS). For methanol solution of complexes M2LX4 (M = Pd(II) and Ni(II), X= Cl and I), two main clusters of peaks were observed which can be assigned to [M2LX3]+ and [M2LX2]2+. When Pd2LCl4 was treated with 2 or 4 mol of AgNO3, it gave rise formation of Pd2LCl2 (NO3)2 · H2O and [Pd2L(H2O)m(NO3)n](4‐n)+, respectively. ESMS spectra show that the dissociation of the former in the ionization process gave peaks of [Pd2LCl2]2+ and [(Pd2LCl2)NO3]+, while dissociation of the later gave the peaks of [Pd2L(CH3CO2)2]2+ and [Pd2L(CH3CO2)2](NO3) + in the presence of acetic acid. Similar species were observed for Pd2LI4 when treated with 4 mol of AgNO3. When [Pd2L · (H2O)m(NO3)n](4‐n)+ reacted with 2 mol of oxalate anions at 40°C, [Pd4L2(C2O4)2(NO3)2]2+ and [Pd4L2(C2O4)2 (NO3)]3+ were detected. This implies the formation of square‐planar molecular box Pd4L2(C2O4)2(NO3)4 in which C2O4? may act as bridging ligands as confirmed by crystal structure analysis. The dissociation form and the stability of complex cations in gaseous state are also discussed. This work provides an excellent example of the usefulness of ESIMS in the identification of metal complexes in solution. 相似文献
955.
He X Li Q Li Y Wang N Song Y Liu X Yuan M Xu W Liu H Wang S Shuai Z Zhu D 《The journal of physical chemistry. B》2007,111(28):8063-8068
A chiral tripod-terpyridine ligand is known to coordinate with Ag+. These complexes self-assemble into chiral aggregates at room temperature. Molecular dynamic simulation reveals the cooperation of tripodal ligand structures with Ag(I) cations, which leads to the formation of helical aggregations, thus the chirality. 相似文献
956.
957.
A new method has been developed to prepare smart microgels that consist of well-defined temperature-sensitive cores with pH-sensitive shells. The microgels were obtained directly from aqueous graft copolymerization of N-isopropylacrylamide and N,N′-methylenebisacrylamide from water-soluble polymers containing amino groups such as poly(ethyleneimine) and chitosan. The gel diameters ranged from 300 to 400 nm with narrow size distribution. The unique core-shell nanostructures exhibited tuneable responses to pH and temperature. 相似文献
958.
Tuning the Reactivity of Isocyano Group: Synthesis of Imidazoles and Imidazoliums from Propargylamines and Isonitriles in the Presence of Multiple Catalysts 下载免费PDF全文
Dr. Shuo Tong Dr. Qian Wang Prof. Dr. Mei‐Xiang Wang Prof. Dr. Jieping Zhu 《Angewandte Chemie (International ed. in English)》2015,54(4):1293-1297
The reaction of propargyl amines with tert‐butylisonitrile in the presence of a catalytic amount of both Yb(OTf)3 and AgOTf afforded imidazoles, whereas the same reaction with primary and secondary alkylisonitriles, as well as arylisonitriles, in the presence of three metal salts [Yb(OTf)3/AgOTf/KOTf] resulted in the 1,3,4,5‐tetrasubstituted imidazoliums in excellent yields. Both chiral amines and chiral isonitriles can be used to provide corresponding chiral heterocycles without racemization. In this multiple catalytic system, Yb(OTf)3 catalyzed the insertion of isonitriles to the N? H bond of amines, AgOTf catalyzed the 5‐exo‐dig cyclization of the resulting amidine nitrogen to the tethered triple bond, and KOTf promoted the salt metathesis, thus providing at the same time the counterion to the imidazolium. Against common knowledge, the isocyano group acted in these reactions as a polarized triple bond instead of conventional carbene‐like function. 相似文献
959.
The direct preparation of a kind of fluorinating reagent 1 [F‐TEDA‐N(SO2Ph)2] was realized in high yield via the complexation of N‐fluorobenzenesulfonimide (NFSI) with 1‐(chloromethyl)‐1,4‐diazabicyclo[2.2.2]octan‐1‐ium N′,N′‐bis‐(benzenesulfonylimide) salt. In its fluorination to oxindoles, the fluorinating products 6 were afforded in moderate to high yields. 相似文献
960.
Jing-Jing Zhu Chao-Feng Zhang Mian Zhang S.W. Annie Bligh Li Yang Zhi-Min Wang Zheng-Tao Wang 《Journal of chromatography. A》2010,1217(33):5384-5388
Six C-glucosyl anthrones were characterized as three pairs of epimers by on-line high performance liquid chromatography–circular dichroism (HPLC–CD) analysis and isolated from the roots of Rumex dentatus by column chromatography. Their structures were elucidated by mass spectrometry, nuclear magnetic spectroscopy and HPLC–CD analysis. They are 10R-C-β-d-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide E, 1) and 10S-C-β-d-glucosyl-10-hydroxyemodin-9-anthrone (rumejaposide F, 2), 10R-C-β-d-glucosylemodin-9-anthrone (rumejaposide G, 3) and 10S-C-β-d-glucosylemodin-9-anthrone (rumejaposide H, 4), 10S-C-β-d-glucosyl-10-hydroxychrysophanol-9-anthrone (cassialoin, 5) and 10R-C-β-d-glucosyl-10-hydroxychrysophanol-9-anthrone (rumejaposide I, 6). Rumejaposides F–I (2–4 and 6) were new C-glucosyl anthrones. Rumejaposide E (1) and cassialoin (5) were isolated for the first time in Rumex plants. On-line HPLC–UV–CD analysis was a useful tool for structure elucidating epimeric C-glycosides anthrones 3–6 because of the poor stability of the pure isomers (3 and 4) and the minute quantity of 5 and 6 in the mixture. 相似文献