中国化学会通讯

第20届国际化学奥林匹克竞赛,于1988年7月2日至8日在芬兰埃斯波举行。此届竞赛,共有26个国家104名选手参赛。中国化学会组织选拔了四名中学生参加,四名选手全部获奖,并荣获团体总分第一名的优异成绩。     

第十八届国际化学奥林匹克简讯

1986.7.6—7.15第十八届国际化学奥林匹克在荷兰来顿举行。22个国家86名中学生参加了竞赛。我国派遣王夔、吴国庆作为观察员出席,为下届参赛作了准备。竞赛分理论试题和化学实验两项,分别为五小时和五个半小时。理论试题共七题,其中无机化学两题、有机化学两题、生物化学一题、结构化学一题、化学工程一题。实验试题为无机合成与容量分析。竞赛结果11人获金质奖,15人获银质奖,25人获铜质奖,此外还向各题最高得分手发了单项奖。荷兰选手成绩最佳,获金质奖、银质奖的各两名。亚洲国家仅科威特参赛,未获奖。据悉,第十九届国际化学奥林匹克将于1987年7月在匈牙利举行。我国已决定组团参赛。从全图选拔选手的工作正在紧张筹备。     

参加第28届国际化学奥林匹克竞赛的中国代表队凯旋归来

以北京大学段连运教授为领队哈尔滨师范大学周宏立教授为副领队的我国参加在俄国首都莫斯科举行的第28届国际化学奥林匹克竞赛的代表队已于7月25日凯旋归来。此届竞赛有45个代表队175名选手参赛。     

第23届国际化学奥林匹克竞赛在波兰举行

第23届国际化学奥林匹克竞赛,于1991年7月7日至14日在波兰罗兹举行。本届竞赛共有30个国家118名中学生参加,通过化学理论和化学实验两项考试,我国选手荣获团体总分第一名和两位并列冠军。我国有4名选手参赛,共获3枚金牌和1枚银牌。     

第31届国际化学奥林匹克竞赛纪实

第31届国际化学奥林匹克竞赛于1999年7月4日至11日在泰国曼谷举行.51个代表队,194名选手参赛(其中印度尼西亚、乌拉圭和委内瑞拉分别只3名选手,而古巴队只1名).另有克罗地亚和乌兹别克斯坦派了观察员.     

我国中学生获第20届国际化学奥林匹克竞赛团体总分第一名

中国化学会在中国科协领导下,受国家教委、国家自然科学基金委员会和中国科协青少年部的委托,组成中国代表团,由王夔教授为领队,一行七人,于今年七月二日至九日在芬兰埃斯波(ESPOO)参加了第20届国际化学奥林匹克竞赛活动。此届竞赛有民主德国、荷兰、英国、苏联、澳大利亚、联邦德国等26个国家的104名选手参赛。我国选手湖北武汉华中师范大学附属中学汪琛以总分93.25分的好成绩夺冠,荣获金牌。     

全国高中学生化学竞赛章程

第一条全国高中学生化学竞赛的目的是：（1）普及化学知识,鼓励青少年接触化学发展的前沿,了解化学对科学技术、社会经济和人民生活的意义,学习化学家的思想方法和工作方法,以激发他们学习化学的兴趣和爱好;（2）探索早期发现和培养优秀中学生和未来人才的思想、方法和途径;（3）促进化学教学新思想与新方法的交流,推动化学教学改革,提高化学教学的水平;（4）选拔参加一年一度的国际化学竞赛的选手。第二条竞赛联合体、时间与选手第一款全国高中学生化学竞赛分两个阶段：第一阶段称XXXX年全国高中学生化学竞赛（初赛）,第二阶段…     

第42届国际化学奥林匹克理论试题

<正>第42届国际化学奥林匹克于2010年7月19～28日在日本东京举行,来自68个国家和地区共267名学生参加了本届竞赛。我国派出了由8人组成的代表队参赛。代表队成员为:选手王汝一(南京师大附     

第35届国际化学奥林匹克竞赛理论考试题

第 35届国际化学奥林匹克竞赛于 2 0 0 3年 7月 5日 - 13日在希腊首都雅典市举行。 5 9个国家和地区共 2 32位选手参加了本届竞赛。竞赛设金牌 30枚 ,银牌 5 3枚 ,铜牌 70枚。我国 4名选手全部获得金牌。他们是 :周焱 (山西省实验中学 )、晏琦帆 (湖北省华中师大一附中 )、倪博 (江苏省启东中学 )和胡蓉蓉 (湖南省师大附中 )。带领他们参赛的是北京大学段连运教授、武汉大学程功臻教授、季振平教授及北京大学裴坚副教授。第一部分　普通化学1　难溶钍盐Th(IO3 ) 4 的溶解度s(摩尔溶解度 ,mol/L)是其溶度积Ksp的函数 ,它们的关系式为 (　…     

第29届国际化学奥林匹克竞赛实验题浅析

第29届国际化学奥林匹克竞赛分两部分进行,即实验与理论。两部分的考试各为5小时,考试日期相隔一天。理论试题共8题60分,中国4名选手的成绩分别为58. 00, 57. 25, 57.00和51. 00,在参赛选手中名列前茅。但实验成绩很不理想,三个实验题共40分,4名选手得分均低于20分(若能高于25分即为金牌)。赛后,教师与学生进行了认真的分析,作为今后参赛的借鉴。     

Dichroism of absorption and polarization of phosphorescence of molecules of the closed form of nitrobenzospirothiopyran

The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997.     

非那雄胺合成工艺改进

非那雄胺能抑制5α-还原酶的活性,明显降低二氢睾酮水平,是一种治疗良性前列腺增生的有效药品。该合成工艺以甾烯酮酸为原料,将其与氯化亚砜反应,无须分离即与叔丁胺反应得17β-酰胺化合物,再氧化开环,环合,氢化,脱氢合成了非那雄胺。经元素分析、IR、1HNMR、13CNMR、MS分析表征了其结构。该法无须使用昂贵的2,2-二吡啶二硫化物和剧毒药品苯亚硒酸酐,且以乙酸铵代替氨气,降低了对设备的要求和腐蚀,更适用于工业生产。     

Determination of heats of detonation and influence of components of composite explosives on heats of detonation of high explosives

The heats of detonation of 20 simple high explosives and explosive mixtures were determined by means of an adiabatic detonation calorimeter designed by the authors. The results indicated that the performance of the instrument was reliable and the experimental data were very accurate. For explosive mixtures, there was a linear accumulative relationship between the heats of detonation of the explosive mixture and its components. Accordingly, the heats of detonation of explosive mixtures could be calculated directly from the heats of detonation of simple explosives and the characteristic heats of other components. The experiments showed that the gold or brass shell of the cylindrical charge could be substituted by a thick-walled porcelain shell, which had the advantage of cheapness.

     

Synthesis of phenolic components of Grains of Paradise

Two vanilloids, (5E)-8-(4-hydroxy-3-methoxyphenyl)oct-5-en-4-one (1) and 4-[3-hydroxydecyl]-2-methoxyphenol (2), isolated from the dried seeds of Grains of Paradise (Aframomum melegueta), were synthesized; the latter compound was made as the S-enantiomer and the material derived from the seeds was found to be a 1:1.7 mixture of the R and S isomers. The synthetic route used should allow the preparation of analogs having extended alkyl chains and consequently different lipophilicity, and 3, a homolog of 2, was also prepared.     

Summary of development of the theory of stability of colloids and thin films

In this review, the research of the author in the field of colloidal systems is summarized. The factors influencing colloidal stability are systematized and analyzed. Examples are presented to illustrate the practical utilization of the theory of stability of colloids and thin films.This review was prepared on the basis of the works of the author, which were awarded the State Premium for 1991 in the field of science and technology, chemistry section.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 8, pp. 1708–1717, August, 1992.     

氯氧化镁生成热的研究

用氧化镁氯化镁水溶液制备了8水合氯氧化镁[nMg(OH)2·MgCl2·8H2O], 并测定了其在盐酸中的溶解热, 实验结果表明, 氯氧化镁溶解热与n值呈线性关系, 根据溶解热求出5Mg(OH)2·MgCl2·8H2O和3Mg(OH)2·MgCl2·8H2O的生成热分别为-7727.1和5888.1kJ·mol^1^-。     

Study of hydration of two cements of different strengths

Main hydration products of two cement pastes, i.e. CSH-gel, portlandite (P) (and specific surface S) were studied by static heating, and by SEM, TEM and XRD, as a function of cement strength (C-33 and C-43) hydration time (th) and subsequent hydration in water vapour.Total change in mass on hydration and air drying, M_o, increased with strength of cement paste and with hydration time. Content of water escaping at 110 to 220°C, defined as water bound with low energy, mainly interlayer and hydrate water, was independent on cement strength but its content increased with (th). Content of chemically bound (zeolitic) water in CSH-gel, escaping at 220-400°C, was slightly dependent on strength and increased with (th). It was possibly derived from the dehydroxylation of CSH-gel and AFm phase. Portlandite water, escaping at 400-500°C, was independent on cement strength and was higher on longer hydration. Large P crystals were formed in the weaker cement paste C-33. Smaller crystals were formed in C-43 but they increased with (th). Carbonate formated on contact with air (calcite, vaterite and aragonite), decomposed in cement at 600-700^oC. It was high in pastes C-33(1 month) and C-43(1 month), i.e. 5.7 and 3.3%, respectively; it was less than 1% after 6 hydration months (low sensitivity to carbonation) in agreement with the XRD study showing carbonates in the air dry paste (1month), and its absence on prolonged hydration (6 months) and on acetone treatment. Water vapour treatment of (6 months) pastes or wetting-drying increased this sensitivity.Nanosized P-crystals, detected by TEM, could contribute to the cement strength; carbonate was observed on the rims of gel clusters.This revised version was published online in November 2005 with corrections to the Cover Date.     

Thermodynamics of the formation of oxosulfides of rare-earth elements

The enthalpies of solution of several oxosulfides of rare-earth elements and the high-temperature enthalpies of oxosulfides and oxosulfates of lanthanum and yttrium were measured using solution calorimetry and high-temperature microcalorimetry techniques. Standard enthalpies of formation and some thermodynamic properties of oxosulfides and oxosulfates were calculated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2 pp. 294–297, February, 1997.     

恶臭嗅辨实验室建设探讨

针对恶臭测试的环境影响问题,提出了解决的实例方案,并对方案的要点及优缺点进行讨论,此方案在实际操作中具有较好的效果。