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51.
Chen C. Y. Kao C. L. Yeh H. C. Li H. T. Wu M. D. Cheng M. J. Li W. J. 《Chemistry of Natural Compounds》2022,58(3):385-386
Chemistry of Natural Compounds - A new ketone, vicamazone (4-(2-butoxyethoxy)-4-methylpentan-2-one) (1), was isolated from the leaves of Victoria amazonica (Nymphaeaceae). The structure of the new... 相似文献
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53.
Chemistry of Natural Compounds - A novel cyclopropanoid, 4-(2-(benzo[d][1,3]dioxol-5-yl)cyclopropoxy)-2,6-dimethoxyphenol (1) was isolated from the stems of Cinnamomum osmophloeum (Lauraceae). The... 相似文献
54.
Wei-Jie Ou Chen-Shan Kao Yih-Shing Duh Jing-Ming Hsu 《Journal of Thermal Analysis and Calorimetry》2014,116(3):1111-1116
Thermal instability of lithiated cathode materials with organic carbonate were investigated using DSC. Lithium transition metal oxides of LiFePO4, LiMn2O4, and LiCoO2 were mixed with diethyl carbonate, dimethyl carbonate, ethylene carbonate, ethyl methyl carbonate, and propylene carbonate then dynamically screened to about 500 °C. Curves were acquired and analyzed to determine exothermic onset temperatures and reaction enthalpies. These data for assessing the thermal hazards of lithium-ion batteries under discharged conditions were compared to those data published in the literature. 相似文献
55.
We reported the first syntheses of 2- and 3-(2-(benzo[b]selenophen-2-yl)-indoles and their Diels–Alder reactions to furnish six unique annulated benzoselenphene carbazoles. This facile route can be used to synthesize selenium-containing biindolyl derivatives that possessed potential pharmaceutical activities. 相似文献
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57.
Shyh-Dar Lee Ging-Ho Hsiue Chen-Yu Kao 《Journal of polymer science. Part A, Polymer chemistry》1996,34(1):141-148
Polyacrylic acid (PAA) was grafted onto the surface of silicone rubber membrane (SR) by plasma-induced graft copolymerization (PIP). Ar-plasma was used to activate the surface of SR. Also, a determination was made of the influences of plasma treatment power, pressure, time, grafted copolymerization reaction time, and monomer concentration on polymerization yield. The surface properties of SR were measured by ATR-FTIR, ESCA, and SIMS. In those analyses, the elemental composition and different carbon bindings on the surface of SR were examined by ESCA with the amount of O1s/C1s being approximately 0.7 at 60 s by Ar-plasma treatment (60 W, 200 mtorr). The peroxide group introduced on SR was measured via 1,1-diphenyl-2-picryhydrazyl (DPPH). The optimum amount of peroxide groups was 6.85 × 10−8 mol/cm2 at 60 s of Ar-plasma treatment. The peroxide group (33D peak) was introduced onto the surface of SR by negative spectra of SIMS analysis after SR treatment by Ar-plasma. An increase was obtained in grafted polymerization yield with a region of 5 to 50% (v/v) of acrylic acid aqueous solution. Both sites of polyacrylic acid were detected after staining by toluidine blue O. That is, a homobifunctional membrane was developed via this surface modification method. © 1996 John Wiley & Sons, Inc. 相似文献
58.
Addition of hydrochloric or hydrobromic acid to a solution of potassium permanganate in acetonitrile produced a homogeneous mixture, which is suitable for laboratory chlorination or bromination, respectively. Aromatic compounds more reactive than alkylbenzenes can be chlorinated or brominated without additional catalyst. Alkenes and alkynes give the corresponding vicinal dihaloalkanes and vinyl halides. All reactions complete within two hours under mild condition (25-60 °C) with excellent to moderate yields. 相似文献
59.
Ab initio molecular orbital theory with the STO-3G and 4-31G basis sets is used to determine the equilibrium geometries, enthalpies of formation, strain energies and spiro-interactions for spiro[3.3]heptane and spiro[3.3]hepta -1,5 - diene. For spiro[3.3]heptane, molecular mechanics calculations suggest that the component cyclobutane rings are puckered to a greater extent than in cyclobutane itself. For spiro[3.3]hepta - 1,5 - diene, STO-3G calculations predict that the component cyclobutene rings deviate slightly from an orthogonal arrangement. Spiro-interactions in spiro[3.3]hepta - 1,5 - diene are revealed by comparing the calculated structural parameters and strain energies with those of appropriate reference systems. The π-orbitals in spiro[3.3]hepta -1,5 -diene are predicted to be split by about 0.4 eV. 相似文献
60.
银环蛇蛇蜕的化学成分研究Ⅱ . 脂肪酸和氨基酸组分 总被引:1,自引:0,他引:1
用色谱-质谱(GC-MS)联用技术分析了银环蛇蛇蜕的脂肪酸成分,鉴定出36种脂肪酸(饱和酸28种不饱和酸8种),在蛇蜕中发现16种饱和二元酸,并发现了自然界中少见的奇数碳脂肪酸14种及支链酸2种,用氨基酸自动分析仪测定了蛇蜕水提取液中的13种游离氨基酸,酸性水解液中17种氨基酸,在蛇蜕中发现存在牛 磺酸。 相似文献