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331.
Abid M. Amin Li Wang Haojie Yu Wael A. Amer Jingmin Gao Tai Yulei 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11):937-946
Polydichlorophosphazenes (PDCP) were synthesized through ring opening polymerization of hexachlorocyclotriphosphazene (HCCP). The polymerization behavior of HCCP under varying conditions of time and amount of catalyst was investigated. The chlorine atoms in polydichlorophosphazenes (PDCP) were substituted with p-oxybenzaldehyde and (or) diethylamine to synthesize poly[bis(p-oxybenzaldehyde diethylamino)phosphazenes](PPOBADEAP), poly[bis(p-oxybenzaldehyde)phosphazenes] (PPOBAP) and poly[bis(diethyl amino) phosphazenes] (PDEAP). The supporting evidence for the success of this synthesis was provided by nuclear magnetic resonance (1H-NMR, and 31P-NMR), gel permeation chromatography (GPC), and energy-dispersive X-ray spectroscopy (EDAX). The self-assembly behavior of PPOBADEAP, PPOBAP and PDEAP was observed in different solvents by the same concentration of polymers. The optical microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images indicated that PPOBADEAP formed various morphologies in different solvents while PPOBAP and PDEAP did not show self-assembly behavior at the same conditions. 相似文献
332.
Jian Tai Fajun Li Yanqing Zhou Zhenzhen Fan Huimin Wei Dong Zhang Lixu Lei 《Journal of Solid State Electrochemistry》2018,22(9):2829-2835
Although tribasic lead sulphate (3BS) has been chemically prepared and found in the cured negative plates of lead-acid batteries (LABs), little was known about its behaviour if it is used directly as their negative active material (NAM). Here, we report a much more facile and energy-saving route to prepare phase pure 3BS powders: after β-PbO is reacted with PbSO4 at 30 °C, elongated 3BS plates of 4~8 μm in length, 1~3 μm in width and 0.1~0.2 μm in thickness are obtained in 4 h. Compared with electrodes prepared from β-PbO, α-PbO and leady oxide, the as-prepared 3BS electrode shows much better performance, which discharges more than 90 at 120 mA g?1 within 100 cycles of 100% DOD (depth of discharge) in a flooded cell. Therefore, 3BS can be used directly as NAM of LABs. It is also worth to notice that using 3BS can reduce the curing/drying time of the plates, thus save energy and produce uniformity in LAB production. 相似文献
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334.
Xue Li Dr. Yonggang Shi Dr. Nan Wang Prof. Tai Peng Prof. Suning Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(22):5757-5767
In order to examine competitive photoisomerization, a series of novel photochromic PtII molecules that contain both dithienylethene (DTE) and B(ppy)Mes2 units (ppy=2-phenylpyridine, Mes=mesityl) were successfully synthesized and fully structurally characterized. Their photochromic properties were examined by UV/Vis, emission and NMR spectroscopy. It was found that the DTE unit in all three compounds is the preferred photoisomerization site, exhibiting reversible photochromism with irradiation. The B(ppy)Mes2 unit does not undergo photoisomerization in these molecules, but likely enhances the photoisomerization quantum efficiency of the DTE moiety through the antenna effect. Extended irradiation with UV light leads to the rearrangement of the ring-closed isomers of DTE. TD-DFT computational studies indicate that the DTE photocyclization proceeds via a triplet pathway through an efficient energy transfer process. 相似文献
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336.
Dr. Ting‐Jen R. Cheng Shi‐Yun Wang Dr. Wen‐Hsien Wen Dr. Ching‐Yao Su Mengi Lin Wen‐I Huang Dr. Ming‐Tsan Liu Dr. Ho‐Sheng Wu Nung‐Sen Wang Chung‐Kai Cheng Chun‐Lin Chen Dr. Chien‐Tai Ren Dr. Chung‐Yi Wu Prof. Jim‐Min Fang Dr. Yih‐Shyun E. Cheng Prof. Chi‐Huey Wong 《Angewandte Chemie (International ed. in English)》2013,52(1):366-370
337.
The development and implementation of quality assurance programs to support nutritional measurements
L. C. Sander M. Bedner D. L. Duewer K. A. Lippa M. M. Phillips K. W. Phinney C. A. Rimmer M. M. Schantz K. E. Sharpless S. S. -C. Tai J. B. Thomas S. A. Wise L. J. Wood J. M. Betz P. M. Coates 《Analytical and bioanalytical chemistry》2013,405(13):4437-4441
The National Institute of Standards and Technology administers quality assurance programs devoted to improving measurements of nutrients and related metabolites in foods, dietary supplements, and serum and plasma samples. These programs have been developed in collaboration with the National Institutes of Health to assist measurement communities in their efforts to achieve accurate results that are comparable among different laboratories and over time. Targeted analytes include micronutrients, botanical markers, nutritional elements, contaminants, fatty acids, and vitamin D metabolites. 相似文献
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339.
Phenylethylamines are important intermediates for many biologically active compounds. As known, phenylethylamines can be obtained by reduction of phenylacetonitrile with Raney nickel or 10% Pd/C1, it also can be prepared from β-nitro-styrene by hydrogenation under high hydrogen pressure1or reduction with LiAlH4 2, borane with catalytic amount of NaBH43 and other methods4. However, the limits of all above methods are high cost , high toxicity and the need of autoclave apparatus. Additional… 相似文献
340.
Dr. Igor O. Koshevoy Yuh‐Chia Chang Dr. Antti J. Karttunen Julia R. Shakirova Prof. Janne Jänis Prof. Matti Haukka Prof. Tapani Pakkanen Prof. Pi‐Tai Chou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(16):5104-5112
A new series of homoleptic alkynyl complexes, [{Au2Cu2(C2R)4}n] (R=C3H7O ( 1 ), C6H11O ( 2 ), C9H19O ( 3 ), C13H11O ( 4 )), were obtained from Au(SC4H8)Cl, Cu(NCMe)4PF6, and the corresponding alkyne in the presence of a base (NEt3). Complexes 1 – 4 aggregate upon crystallization into polymeric chains through extensive metallophilic interactions. The cluster that contains fluorenolyl functionalities, C13H9O ( 5 ), crystallizes in its molecular form as a disolvate, [Au2Cu2(C2C13H9O)4] ? 2 THF. The substitution of weakly bound THF molecules with pyridine molecules leads to the complex [Au2Cu2(C2C13H9O)4] ? 2 py ( 6 ), thus giving two polymorphs in the solid state. Such structural diversity is established through metal‐chain and hydrogen‐bond formation, which depends on the stereochemical characteristics of the organic ligands. More interestingly, this solid‐state structural arrangement affords good emission properties, such as intensity and spectroscopic profile, which are otherwise very weakly emissive in solution. Metallophilic aggregation of the {Au2Cu2} cluster units, as observed in the crystals, results in dramatic enhancement of the room‐temperature phosphorescence, thereby reaching a maximum quantum efficiency of 95 % ( 4 ). A theoretical approach further indicates a synergistic effect of the array of the metal chain upon aggregation, which greatly enhances the spin‐orbit coupling and, hence, the phosphorescence, thereby opening up a new direction in the field of aggregate‐enhanced emission. 相似文献