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991.
992.
Wang H Liu X Wang Z Li H Li D Meng Q Chen L 《The journal of physical chemistry. B》2006,110(12):5970-5974
It was observed that the ionic conductivity of the solid-state electrolyte LiI/3-hydroxypropionitrile (HPN) = 1:4 (molar ratio) decreased dramatically with increasing iodine (I(2)) concentration, which differs from the conduction behavior of the Grotthuss transport mechanism observed in liquid or gel electrolytes. The short-circuit photocurrent density (J(sc)) of the dye-sensitized solar cell (DSSC) based on this electrolyte system increases with increasing I(2) concentration until LiI/I(2) is 1:0.05 (molar ratio). Beyond this limitation, the J(sc) decreases. At low I(2) concentrations (I(2)/LiI < or = 0.05), the J(sc) is mainly affected by the diffusion of I(3)(-). An increase of the I(2) concentration leads to the enhancement of the diffusion of I(3)(-) and an increase of the J(sc). At high I(2) concentrations (I(2)/LiI > 0.05), the factors, including the increased light absorption by the I(3)(-), the increased recombination of electrons at the photoanode with I(3)(-), and the reduced ionic conductivity of the electrolyte, lead to a decrease of J(sc). At the same time, the open-circuit voltage (V(oc)) of the DSSC decreases monotonically with the ratio of I(2)/LiI due to increased dark current in the DSSC. The increased absorption of visible light by the electrolyte, the enhanced dark current, and the reduced ionic conductivity of the electrolyte contribute to the performance variation of the corresponding solid-state DSSC with increasing I(2) concentration. 相似文献
993.
Reaction of lithium salts of anilido-imine ligands bearing bulky substituentes on the nitrogen donor atoms with trans-chloro(phenyl)bis(triphenylphosphane)nickel(II) results in the formation of two rare three-coordinate nickel(I) complexes [(Ar1N=CHC6H4NAr2)Ni(I)PPh3] (1: Ar1 = Ar2 = 2,6-i-Pr2C6H3; 2: Ar1 = 2,6-Me2C6H3, Ar2 = 2,6-i-Pr2C6H3). The molecular structures of complexes 1 and 2 have been confirmed by single crystal X-ray analyses. These two complexes exhibit paramagnetic properties as measured by their EPR and 1H NMR spectra. After being activated with methylaluminoxane (MAO) these complexes could polymerize norbornene to afford addition-type polynorbornene (PNB) with high molecular weight M(w) (10(6) g mol(-1)), catalytic activities being high, up to 2.82 x 10(7) g(PNB) mol(-1)(Ni) h(-1). 相似文献
994.
Metal–Organic Framework/PVDF Composite Membranes with High H2 Permselectivity Synthesized by Ammoniation 下载免费PDF全文
Dr. Wanbin Li Prof. Dr. Qin Meng Dr. Congyang Zhang Prof. Dr. Guoliang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(19):7224-7230
Herein we report a new ammoniation‐based chemical modification strategy for synthesis of continuous and uniform metal–organic framework (MOF)/polyvinylidene fluoride (PVDF) membranes with attractive performance. Ammoniation can promote the support PVDF membrane to produce amino groups, form a nanoparticle structure, and be well cross‐linked; therefore, the high‐density heterogeneous nucleation sites for MOFs growth were provided and the thermal stability and chemical resistance of composite membranes can be greatly improved. The high‐quality layers of representative Cu‐BTC and ZIF‐8 were synthesized on the chemically modified PVDF membranes. By ammoniation, ZIF‐7 can even be grown under harsh synthetic conditions such as in DMF precursor solutions at 403 K. The fabricated MOF/PVDF composite membranes with excellent hollow fiber structures and enhanced structural stability exhibited high H2 permselectivities for H2/CO2 and H2/N2. 相似文献
995.
ZOU DingBiao QIU YaTao TU ZhengChao LIAO ChenZhong LUO JinFeng MENG QingQing YAO RiSheng LI Zheng JIANG Sheng 《中国科学:化学(英文版)》2014,57(6):823-832
We designed a series of 2-methylpyrimidine derivatives as new BCR-ABL inhibitors using scaffold-hopping strategy.These synthetic compounds exhibited significant inhibition against a broad spectrum of Bcr-Abl mutants including the gatekeeper T315I mutant.Compound 7u showed very potent kinase inhibitory activities against Bcr-Abl WT,Bcr-Abl E255K,Bcr-Abl Q252H,Bcr-Abl G250E and Bcr-Abl T315I,with IC50 values of 0.13 nM,0.17 nM,0.24 nM,0.19 nM and 0.65μM,respectively.This compound also displayed anti-proliferation activity against K562 cell line with an IC50 value of 1.1 nM,thus representing a new lead for further optimization. 相似文献
996.
Jason L. Nyrop Arash Soheili Rong Xiang Fanyu Meng Jacob H. Waldman Xiujuan Jia Rubina Giarre Parmar Benjamin W. Thuronyi J. Michael Williams Lisa DiMichele Michel Journet Bonnie J. Howell Bing Mao Ian W. Davies Steven L. Colletti Laura Sepp‐Lorenzino Erin N. Guidry 《Journal of polymer science. Part A, Polymer chemistry》2014,52(8):1119-1129
Synthetic polymers represent a modifiable class of materials that can serve as adjuvants to address challenges in numerous biomedical and medicinal chemistry applications including the delivery of siRNA. Polymer‐based therapeutics offer unique challenges in both synthesis and characterization as compared to small molecule therapeutics. The ability to control the structure of the polymer is critical in creating a therapeutic. Reported herein, are batch and flow polymerization processes to produce amphiphilic terpolymers through a Lewis acid BF3OEt2‐catalyzed polymerization. These processes focus on controlling reaction variables, which affect polymer structure in this rapid, exothermic, nonliving cationic polymerization. In addition to analytical characterization of the polymers, the in vivo activity of the polymer‐siRNA conjugates is also highlighted—demonstrating that the method of synthesis does affect the in vivo activity of the resulting polymer conjugate. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1119–1129 相似文献
997.
Sheng‐Run Zheng Xi‐Ling Wen Zi‐Meng Liu Tao Xie Jing‐Bo Tan Jun Fan Shuang‐Shuang Hou Wei‐Guang Zhang 《无机化学与普通化学杂志》2014,640(10):2057-2061
Two coordination polymers (CPs), namely, [Cu(Hptz)2(Hhba)2]n ( 1 ) [Hptz = 5‐(4‐pyridyl)‐1H‐tetrazole, H2hba = 2‐hydroxybenzoic acid] and [Zn3(ptz)2(hpa)2]n ( 2 ) (H2hpa = 2‐hydroxy‐2‐phenylacetic acid), were synthesized by solvothermal reactions. Both complexes were characterized by elemental analysis, infrared spectroscopy, powder X‐ray diffraction, thermogravimetric analysis, and single‐crystal X‐ray diffraction analysis. Compound 1 exhibits a 2D (4,4) network, where each layer connects to four adjacent layers to construct a 3D supramolecular framework. Compound 2 has a 3D framework structure composed of 1D SUBs, which are formed by both carboxyl and tetrazole groups. The complexes represent two rare examples of CPs constructed from Hptz and organic carboxyl acid ligands. Complex 2 exhibits intense, red‐shifted emissions in the visible region at room temperature. 相似文献
998.
Chunhua Luo Zhitao Shen Xiangjian Meng Li Han Shuo Sun Tie Lin Jinglan Sun Hui Peng Junhao Chu 《先进技术聚合物》2014,25(8):809-815
Three of conjugated polymers based on pyromellitic diimide (PMDI) as the acceptor unit and thienothiophene (TT) as the donor unit were successfully synthesized by Stille coupling. The effect of the side chain length and thiophene π‐bridge on the polymers' optical and electrochemical properties was investigated. Electrochemical characterization indicated that these polymers have deep highest occupied molecular orbital energy levels between ?5.7 and ?5.8 eV. Polymer solar cells were fabricated by using these PMDI‐based polymers as the donor and [6,6]‐phenyl‐C61‐butyric acid methyl ester as the acceptor. The polymer P1 whose PMDI unit was functionalized with 2‐ethylhexyl side chain shows the higher short‐circuit current (Jsc) and fill factor (FF) compared with that of P2 with a 2‐octyldodecyl side chain on the PMDI unit. The results also illustrate that the insertion of a thiophene π‐bridge between PMDI and TT (the polymer P3) leads to the broader absorption and better photovoltaic performance. The best performance was obtained from the cell based on the polymer P3 with a power conversion efficiency of 0.43% under the illumination of AM 1.5 G, 100 mW/cm2. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
999.
Hao Guo Lie-Wei Zhang Hao Zhou Dr. Wei Meng Dr. Yu-Fei Ao Prof. Dr. De-Xian Wang Prof. Dr. Qi-Qiang Wang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(7):2645-2649
An artificial system of substrate-induced dimerization assembly of chiral macrocycle catalysts enables a highly cooperative hydrogen-bonding activation network for efficient enantioselective transformation. These macrocycles contain two thiourea and two chiral diamine moieties and dimerize with sulfate to form a sandwich-like assembly. The macrocycles then adopt an extended conformation and reciprocally complement the hydrogen-bonding interaction sites. Inspired by the guest-induced dynamic assembly, these macrocycles catalyze the decarboxylative Mannich reaction of cyclic aldimines containing a sulfamate heading group. The imine substrate can be activated toward nucleophilic attack of β-ketoacid by a cooperative hydrogen-bonding network enabled by sulfamate-induced dimerization assembly of the macrocycle catalysts. Highly efficient (>95 % yield in most cases) and enantioselective (up to 97.5:2.5 er) transformation of a variety of substrates using only 5 mol % macrocycle was achieved. 相似文献