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951.
952.
Yuan AH Qian SY Liu WY Zhou H Song Y 《Dalton transactions (Cambridge, England : 2003)》2011,40(19):5302-5306
Reactions of the precursors [Ni(macrocyclic ligand)](2+) with [W(CN)(8)](3-) afford two octacyanotungstate-based assemblies, (H(2)L(1))(0.5)[Ni(L(1))][W(CN)(8)]·2DMF·H(2)O (L(1) = 5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane) (1) and [Ni(L(2))](3)[W(CN)(8)](2)·4H(2)O (L(2) = 3,10-dipropyl-1,3,5,8,10,12-hexaazacyclotetradecane) (2). Single crystal X-ray diffraction shows that 1 consists of anionic one-dimensional (1D) linear chains, while 2 is built of 2D graphite-like layers with (6, 3) topology. Magnetic studies reveal that both complexes exhibit metamagnetic behavior from the spin-canted antiferromagnet to the ferromagnet induced by field. 相似文献
953.
The UV‐cured organic‐inorganic hybrid nanocomposite (nano‐Si‐m‐PI) was prepared through the photopolymerization of acrylic resin initiated by ethoxysilane‐modified multifunctional oligomeric photoinitiator (Si‐m‐PI). The esterification reaction of 2‐hydroxy‐4′‐(2‐hydroxyethoxy)‐2‐methylpropiophenone (Irgacure 2959) with thioglycolic acid, and the following addition reactions with dipentaerythritol hexaacrylate and then 3‐aminopropyltriethoxysilane were carried out for preparing the Si‐m‐PI. The Si‐m‐PI exhibits the similar UV absorption and molar extinction coefficient with Irgacure 2959. The photoinitiating activity study by photo‐DSC analysis showed that the Si‐m‐PI possesses high photopolymerization rate at the peak maximum (Rpmax) and final unsaturation conversion (Pf) in the cured hybrid films. From the scanning electron microscope (SEM) observation, the SiO2 nanoparticles dispersed uniformly in the formed nano‐Si‐m‐PI, whereas the aggregation of nanoparticals occurred in nano‐Irg, which was prepared through the photopolymerization of acrylic resin initiated by Irgacure 2959. Moreover, compared with the UV‐cured pure polymer and nano‐Irg, the nano‐Si‐m‐PI showed remarkably enhanced thermal stability and mechanical properties. 相似文献
954.
955.
956.
Two new Fischer-type carbene-containing trinuclear transition-metal clusters: (μ
3-S)Co3(CO)7[μ, η
2-SCNEt2] 1 and CoRu2(CO)9[μ
3, η
2-SCNEt2] 2 were obtained by the reaction of tris(N,N-diethyldithiocarbamato)cobalt with Co2(CO)8 and Ru3(CO)12. These clusters contain thiocarboxamido ligand in different coordination modes. The thiocarboxamido ligand served as monometalated
or dimetalated sulfur(diethy1amino) carbene ligand in these clusters. Clusters 1 and 2 were characterized by IR, 1H NMR, and single-crystal X-ray diffraction. 相似文献
957.
Yu Huilan Dong Junjun Hu Zhen Pei Chengxin Liu Shilei Xiang Yu 《Phosphorus, sulfur, and silicon and the related elements》2016,191(1):111-116
A new method for the synthesis of organophosphorylated adducts of the nonapeptide FGESAGAAS is presented. The adducts were obtained by using sarin (GB) or soman (GD) as the organophosphorylating reagents and cesium carbonate as the acid scavenger. Greater than 50% of the peptide was modified on serine 4. MS/MS spectra acquired on an Agilent 6520 quadrupole time of flight mass spectrometer demonstrated that serine 4, but not serine 9 in the nonapeptide, was modified. The adducts included the characteristic isopropyl group of sarin and the pinacolyl group of soman, indicating that aging had not occurred. It was concluded that the new synthetic method yielded sarin and soman-modified peptides that could be used as references when analyzing human exposure to these nerve agents. 相似文献
958.
Yan Guochun Li Xinhai Wang Zhixing Guo Huajun Peng Wenjie Hu Qiyang 《Journal of Solid State Electrochemistry》2016,20(2):507-516
Journal of Solid State Electrochemistry - Lithium bis(fluorosulfony)imide (LiFSI) is a promising alternative lithium salt to replace lithium hexafluorophosphate (LiPF6) due to its high conductivity... 相似文献
959.
Hydrogen evolution bothers stripping analysis significantly. Dioctyl phthalate-based carbon paste electrode exhibits extremely wide cathodic potential window. It is explored as a powerful substrate electrode to solve the problem of hydrogen evolution and further improve reproducibility for stripping analysis using bismuth-coated electrodes for the first time. It was successfully applied to the simultaneous determination of Zn2+, Cd2+, and Pb2+. Linear responses are obtained for Zn2+ in the range of 10–100 μg L−1 and for Pb2+ and Cd2+ in the range of 5–100 μg L−1. The detection limits for Zn2+, Cd2+, and Pb2+ are 0.1 μg L−1, 0.22 μg L−1 and 0.44 μg L−1, respectively. The method has been successfully applied to the determination of Zn2+, Cd2+, and Pb2+ in waste water samples. The detection strategy based on the combination of dioctyl phthalate-based carbon paste electrode and bismuth-coated electrodes holds great promise for stripping analysis. 相似文献
960.
Junfeng Xiao Yuan Hu Ling Yang Lei Song Weicheng Fan 《Polymer Degradation and Stability》2006,91(9):2093-2100
The fire retardant efficiency of melamine (MA) and triphenyl phosphate (TPP) in poly(butylene terephthalate) (PBT) was studied by the limiting oxygen index (LOI) and the UL94 test. On adding 10 wt. % MA and 20 wt. % TPP, LOI increased from 20.9 to 26.6 and the UL94 V-0 rating was achieved. SEM and DSC analyses show that the fire retardants are compatible with PBT and facilitate crystallization of PBT. The occurrence of an interaction between MA + TPP and PBT was elucidated by TGA, dynamic FTIR, and pyrolysis/GC/MS. MA + TPP changes the degradation path of PBT and modifies the compositions of the gas and condensed-phase products. 相似文献