东莞市石碣镇幼儿园儿童发铅水平调查分析

报道了东莞市石碣镇 969名 2～ 6岁幼儿园入托儿童发铅含量的调查分析。结果显示 ,石碣镇幼儿园 2～ 6岁儿童发铅含量为 ( 1 0 51± 3 0 0 )× 1 0 - 6 ,儿童发铅≥ 1 0 0× 1 0 - 6 者占调查人数的 63 88% ;男、女童之间发铅水平无特别显著差异 ,但两者的高发铅比率有明显差异 ;5岁前后的儿童在发铅水平及高发铅比率方面均存在显著差异。通过发铅检测 ,可早期发现高发铅儿童 ,并及时采用干预措施 ,对预防儿童铅中毒是非常重要的     

学龄期儿童头发铅水平的调查

采用原子吸收光谱法测定南城县小学 541名学龄期儿童头发中铅的水平。调查所得资料属非正态性资料。儿童发铅中位数为 7 4 5× 10 - 6 ;四分位数间距为 10 0 5× 10 - 6 ;发铅 >10× 10 - 6 者占 37 33% ;男女发铅“超标流行率”有显著性差异 ;无论男女年龄与发铅值均无相关。     

沙棘颗粒对发铅高儿童的干预治疗

为探讨发铅值升高儿童的干预治疗方法,将45例发铅水平在10.14×10-6-17.38×10-6的儿童随机分为两组:治疗组口服沙棘颗粒冲剂;对照组口服“迪巧”。分别于干预2个月后复查了发铅水平。结果表明,治疗组(n=23)干预后的发铅水平由15.34×10-6±4.62×10-6下降到9.03×10-6±3.76×10-6,下降了41.1％;对照组(n=22)由14.82×10-6±4.37×10-6下降到10.54×10-6±3.62×10-6.下降了28.9％。干预前各组问发铅的水平没有差异(P>0.05),而干预后治疗组与对照组比较,对照组与治疗组之间有显著差异。提示沙棘冲剂有降低发铅水平的作用,效果较单用钙剂为好。     

160例学龄前,学龄儿童发铅含量测定

采用日本岛津AA-670型全自动原子吸收分光光度计、Air／C2H2标准曲线法测定学龄前儿童（2-6岁）100例,学龄儿童（7-11岁）60例头发中铅的含量.结果表明,学龄前儿童发铅含量为11.05×10-6±5.06×10-6.学龄后儿童发铅含量为7.53×10-6±4.28×10-6.经t检验：P＜0.01,两者具有高显著性差异.     

儿童发铅与智商关系的研究

为探讨环境中低浓度铅对儿童智商的影响，选择131名合肥市某小学四年级学生，以其发铅水平作为铅暴露指标，智商为效应指标。结果发现：131名儿童发铅值水平在0．05×10－6～8．35×10-6（均数上标准差为2．57×10－6±1．87±10-6，拟和智商（FIQ）水平在72～135（均数±标准差为105．27±12．68）。以3．5×10-6和1．5×10－6发铅值为分界线进行t检验，结果发现，发铅值在较低水平时（1．5×10－6）时，仍对智商有影响（P＜0．05）。控制11个对智商有影响的混杂因素后，经多元逐步回归分析，发铅值排在11个影响因素中的第2位。     

齿铅与儿童心理缺陷

在 2 0世纪 80年代以前 ,许多人探讨了铅对儿童神经心理的影响。Ｎｅｅｄｌｅｍａｎ发现 ,低水平铅暴露即可影响儿童的语言、听觉、注意力和课堂行为 ,1 1项课堂行为的教师评分与齿铅水平有剂量 -效应关系。如果按齿铅含量将儿童分为高铅组 (ｎ =5 8,齿铅 >2 0× 1 0 6 )和低铅组 (ｎ =1 0 0 ,齿铅 <1 0× 1 0 6 ) ,在 1 1项多动行为评分中有 9项有显著差异 ,总评分也有十分显著的差异。在心理测试前四年测定的血铅水平 ,高铅组平均值为 1 71 5± 0 487μｍｏｌ/Ｌ ( 3 5 5± 1 0 1 μｇ/ｄＬ) ,低铅组平均值为 1 1 49± 0 2 89μｍ…     

清远市幼儿发铅水平调查和相关因素分析

为调查清远市幼儿发铅水平和相关因素 ,对 96名年龄在 2～ 3岁的健康幼儿进行了发铅检测 ,并根据居住环境、父母职业、饮食习惯进行了分组比较。结果表明 ,居住于市内组发铅(8 1 2± 1 1 1 )× 1 0 - 6 高于居住于市外组 (7 3 5± 0 5 5 )× 1 0 - 6 ,P <0 0 1 ,父母职业可能接触铅组(8 1 9± 1 0 5 )× 1 0 - 6 高于父母职业不接触铅组 (7 41± 0 62 )× 1 0 - 6 ,P <0 0 0 1。喝牛奶组 (7 2 7± 0 5 0 )× 1 0 - 6 低于不喝牛奶组 (8 2 7± 0 99)× 1 0 - 6 ,P <0 0 0 1。可见居住环境、父母职业、饮食习惯的影响发铅含量     

32例反复呼吸道感染患儿发铅研究

研究了铅对儿童免疫系统的影响。选择了32例反复呼吸道感染患儿作为研究对象,38例健康儿童为对照。结果表明,患儿发铅含量(26.7±14.1)×10~(-6),高于对照组发铅含量(19.4±9.1)×10~(-6),经统计学处理,两者有显著性差异,t=2.59,P<0.05。证实铅对人体免疫力具有抑制作用,可增加小儿对致病微生物的敏感性。     

阳江市儿童微量元素防治研究

对阳江市 1～ 7岁儿童采用微量元素防治前、后头发中的元素含量进行了对照研究。结果显示 ,防治后儿童头发Zn [( 84 37± 1 6 32 )× 1 0 -6]、Ca [( 71 7 62± 83 1 8)× 1 0 -6]、Mn[( 3 2 3± 0 93)× 1 0 -6]均显著高于防治前儿童的发Zn [( 82 1 5± 1 9 0 0 )× 1 0 -6,P <0 0 1 ]、Ca[( 5 1 1 5 6± 93 5 5 )× 1 0 -6,P <0 0 1 ]、Mn [( 1 81± 0 86)× 1 0 -6,P <0 0 1 ]的含量。而儿童在防治后的发Pb含量 [( 1 0 1 6± 2 2 8)× 1 0 -6]则显著低于防治前的发Pb [( 1 2 82± 7 4 3)×1 0 -6,P <0 0 1 ]。还分别对男童和女童在防治前、后头发中的微量元素含量进行了对比研究。结果表明 ,阳江地区采取的干预措施是提高当地儿童体内微量元素水平的一条有效途径。     

糖尿病人及糖尿病孕妇铅代谢观察

采用高频等离子体发射光谱法测定75例糖尿病患者头发铅含量，平均值为（2．68±2．23）×10－6，而健康对照组头发铅平均值为（1．61±1．68）×10－6，两者相比较有显著性差异，糖尿病患者组显著高于对照组。但因怀孕而引起糖尿病的孕妇与正常孕妇的发铅含量比较，两者并没有显著性差异，分别为（1．51±1．17）×10－6和（1．25±1．25）×10－6（P＞0．05），说明一般糖尿病患者与糖尿病孕妇的铅代谢并不一致。本研究还就糖尿病的不同分型、遗传、有无并发症等因素分析了铅的代谢情况。结果显示非胰岛素依赖型的糖尿病人铅含量明显高于胰岛素依赖型糖尿病人，铅在糖尿病的形成和发展中所起的作用值得进一步深人探讨。     

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.     

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.     

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^-。     

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。