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51.
52.
Jin Yan Dong Ye Gao Chen Hong Chuan Song Yan Ping He Lei Li Yong Ping Zhong Yan Hui Zhu Jie Cao Luo Wang Ke Qin Zhang Laboratory for Conservation Utilization of Bioresources Yunnan University Kunming China Department of Chemistry Yunnan Normal University Kunming China Provincial Key Lab of Rural Energy Engineering Yunnan Normal University Kunming China 《中国化学快报》2007,18(2):165-167
Microbial transformation of nigranoic acid by Caryospora carllicarpa YMF1.01026 afforded the new derivative 6β-hydro-xynigranoic acid. Its structure was elucidated by spectroscopic methods. 相似文献
53.
复合Fe2O3纳米粒子的高分子微球的结构表征 总被引:6,自引:0,他引:6
近年来,复合有机、无机粒子的高分子微球及其特殊性质越来越引起人们的兴趣与关注[1].获得有机、无机复合微球的方法很多,如在无机粒子存在下的乳液或无皂乳液聚会[2,3],通过可聚合的表面活性剂在粒子表面形成胶囊化层[4]以及共沉淀法等[5].这些无机粒子包括氧化钛、氧化铁、氧化铝及氧化硅等.Haga等[6]增发现包覆在聚合物粒子中的CdS与其本体的光电性质不同;单分散的聚合物微球可以在基片上被组装成二维乃至三维有序的结构[7].这为信息存储、立体印刷等领域提供了新途径.因此,将无机粒子与聚合物复合成为功能化粒子是一项有… 相似文献
54.
用共振电离飞行时间质谱仪分析土壤中超痕量气态金 总被引:2,自引:0,他引:2
采用激光共振电离飞行时间质谱技术(简称RIS-TOF技术)对土壤中超痕量气态金的含量进行了分析研究。RIS-TOF谱仪具有极高的灵敏度和很强的选择性,避免了对样品的预富集过程。本文给出了该谱仪对金元素的检测限和65个土壤中气态金样品的分析结果,以及用中子活化法随机抽样检查的结果。 相似文献
55.
Li-Juan Jia Yuan-Yuan Wang Hui Chen Yong-Kui Shan Li-Yi Dai 《Reaction Kinetics and Catalysis Letters》2005,86(2):267-273
Summary The alkylation of benzene with 1-hexene has been investigated in different triethylamine hydrochloride-ferric chloride (Et3NHCl-FeCl3) and triethylamine hydrochloride-aluminium chloride (Et3NHCl-AlCl3) ionic liquids. Both high catalyst activity and monoalkylation selectivity were observed for these two type of ionic liquids.
Systems prepared by modification with HCl in Et3NHCl-FeCl3ionic liquids prove to be very suitable solvents and catalysts for the reaction. When employing Et3NHCl-AlCl3ionic liquids as catalysts, the reaction takes place in biphasic mode with facile catalyst separation and catalyst recycling. 相似文献
56.
Two-dimensional protein database of human pancreas 总被引:7,自引:0,他引:7
We report here the two-dimensional protein database of human pancreas. The proteins were analyzed by two-dimensional electrophoresis followed by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS). Totally, 302 proteins were identified, of which about 27% were enzymes with a broad range of catalytic activities. Several of these are specifically expressed in pancreas, such as pancreatic amylase, pancreatic stone protein, pancreatitis-associated protein, pancreatic lipase, pancreatic elastase, etc. Structural and cytoskeletal proteins are also strongly represented on the gels. Thus, the pancreatic proteome reflects the organ's function. This work paves the way for further studies on pancreatic protein expression in health and disease, such as diabetes and pancreatic cancer. 相似文献
57.
微乳液介质—1—(2—吡啶偶氮)—2—萘酚光度法测定汽油中环烷酸铁的含量 总被引:8,自引:2,他引:8
本研究了微乳液为介质时,铁与1-(2-吡啶偶氮)-2-萘酚(PAN)的显色反应。选择730nm处为测定波长,ε为1.4×10^4L.mol^-^1.cm^-^1,铁量在0-50μg/25ml范围内符合比耳定律,该法适用于汽油中环烷酸铁的测定。 相似文献
58.
59.
根据Flory热力学统计理论和比容-熔融热作国法,由DSC结果得到了不同联苯含量的聚醚醚酮酮-含联苯聚醚醚酮酮(PEEKK-PEBEKK)共聚物的熔融热,两种方法获得的结果吻合。在此基础上给出了PEEKK-PEBEKK共聚物不同联苯含量的熔点计算表达式。结果还表明,随着联苯含量nB,的变化,明显改变;当nB=0.35时,PEEKKPEBEKK共聚物的值最小。 相似文献
60.
N,N-Dimethyl diethyl, dipropyl, dibutyl, and N-monoisopropylaminoaphthylenesulfonyl derivatives of melanotropin inhibiting factor (MIF) and its metabolites were prepared, and their chromatographic behavior was investigated with thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC), using five solvent systems on polyamide layers and ten solvent systems on muBondapak C18 and muBondapak phenyl columns. A mixture of MIF and its metabolites derivatized with Dns chloride was adequately resolved by two-dimensional chromatography on polyamide layer with solvent systems, formic acid-water (3:97) and benzene-acetic acid (9:1). Bns-MIF and its metabolites were separated with muBondapak C18 column with the solvent system acetonitrile-0.01 M sodium sulphate buffer, pH 7 (50:50). They were separated into five groups: Gly and Bns acid; Pro-Leu, Leu-Gly and Leu; Pro; Gly-NH2; and MIF. The alkylaminonaphthylenesulfonyl derivates had strong fluorescence, which permitted their detection at the level of 10(-11) to 10(-9) mol. Dns-MIF and its derivatives had the lowest detectable amounts. HPLC with the aid of the Dns derivation is reliable and fast, and is the preferable method for study of neuropeptide breakdown. 相似文献