A New Steroidal Alkaloid from Bulbs of Fritillaria Hupehensis Hsiao et K. C. Hsia

Fritillaria hupehensis Hsiao et K. C. Hsia is a liliaceous plant growing in the southwest district of Hubei Province, China. Its bulbs have been recorded in the Pharmacopoeia of the People‘s Republic of China as one of the principal traditional Chinese herbs named “Hubeibeimu”.     

RECIPROCAL A.C.OSCILLOPOLAROGRAM

In this paper a new electrochemical method“Reciprocal a.c.oscillololarography”is discussed.Both principle and experimental work aredescribed.     

C.A.索引图表分析

一、C.A.有哪些索引美国《化学文摘》(Chemical Abstracts——C.A.)从1907年创刊至今七十余年,索引从少到多,从简单     

N. K. Kochetkov (18.05.1915–21.12.2005)

In Memoriam

N. K. Kochetkov (18.05.1915–21.12.2005)     

A new coumarin from Wikstroemia indica （L.） C. A. Mey

A new coumadn was obtained from the stems and roots of Wikstroemia indica (L.) C.A.Mey.Its structure was elucidated as methyl 3-(2-hydroxy-4-(7-hydroxy-6-methoxy-2-oxo-2H-chromen-3-yloxy) phenyl) propanoate by spectroscopic methods.     

K.齐格勒博士和G.纳塔博士的业绩

K.齐格勒和G.纳塔两位博士是世界闻名的卓越的化学家,是齐格勒-纳塔型催化剂体系的创始人,也是诺贝尔化学奖的获得者。五十年代中期,由于齐格勒-纳塔型催化剂的出现而使聚烯烃工业崛起,从而使高分子合成材     

FREQUENCY-SPECTRUM ANALYSIS OF A.C.OSCILLOPOLAROGRAM

Application of Frequency-Spectrum analysis to a.c,oscillopolarogram using Fourier transform technique is given in this paper.Harmonic equations of E-t curve of base solution are derived.The measurementof concentration of the depolarizer by means of the second and third harmoniopotentials were also described.     

F.A.凯库勒生平简介

100年前的1890年3月10日,德国化学会为纪念凯库勒(F.A.Kekulé)教授提出苯的环状结构学说25周年,举行了隆重仪式,他以前的学生拜耳(A.von.Baeyer,1835～1917)做了有关凯库勒学术贡献的长篇发言。凯库勒也做了有关他本人学术经历与生平的讲演,向公众第一次提到了他在近似梦幻的状况下解决苯的环状结构的情景。     

著名美国无机化学家F.A.科顿

弗兰克·阿伯特·科顿(Frank Albert Cotton)这个名字对我国化学工作者,特别是无机化学工作者来说并不陌生。他的著作《群论在化学中的应用》早就被译为中文,成为我国读者学习化学中的群论时所用的一本很好教科书或参考书。澳大利亚皇家化学研究院评价他和G.威尔金森合著的《高等无机化学》时,认为“这是每个化学家‘必须’看的书”。科顿于1930年4月9日出生于美国宾夕法尼亚     

A review of: “Handbook of Derivatives for Chromatography. K. Blau and G. S. King (editors). Heyden Publishers,London, Bellmawr,N.J., Rheine, 1977. xvi f 576 pages. Price £24.00: U.S.A. $48.0: DM 154.00.”

Abstract

Urban particulate matter, collected from Washington, DC and certified by the National Institute of Standards and Technology (NIST) as Standard Reference Material 1649, was extracted and fractionated into acid, base and neutral fractions. Each fraction was tested for biological activity using a microbial mutagenesis assay system. The organic acid fraction showed unexpectedly high mutagenic activity, and was subjected to chemical characterization studies. Following derivatization, analysis by GC/MS showed the presence of fatty acids, aromatic acids (including phenolic compounds), and a significant number of compounds that could not be identified from mass spectral compendia. Spectroscopic and elemental analysis data supported the characterization of the fraction as predominantly aromatic. Mass spectra from both GC/MS and direct probe analysis showed the presence of a chlorinated substance, subsequently identified as the fungicide Dichlorophen. The compound was shown to comprise over 50% of the mass of the organic acid fraction. A reference standard of Dichlorophen was not mutagenic. The presence of the fungicide in the NIST certified urban aerosol is, in all probability, due to artifactual processes. Attempts to concentrate the observed mutagenic activity by preparative chromatography and acid/base partition experiments were not successful.