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1.
按东西南北中五个方位抽取了襄樊市70所小学2800名8-10岁儿童进行了碘营养状况调查。以解诊和B超法检查甲状腺肿大率为主要指标,盐碘含量、尿碘水平为重要参考指标。结果表明:8-10岁儿童甲肿率触诊法和B超法分别为10.25%和8.25%,两者符合率为96.64%,甲肿率均超过5%,尿碘中位数为439.81μg/L,尿碘值大于100μg/L得占96.67%;儿童家中食盐含碘中位数为31.30*10  相似文献   

2.
对哈尔滨市平房区7~10岁学龄儿童尿碘、甲状腺肿及用户碘盐进行调查,其结果为:尿碘中位数为315μg/L,<50μg/L者占5.7%,<100μg/L者占10.6%;甲状腺肿大率为21.80%;盐碘中位数为46.4×10-6,<20×10-6者占3.9%,按照WHO、UNICEF、ICCIDD三个国际组织提供的考核评估标准,尿碘、盐碘水平已达标,但甲状腺肿大率未达标。  相似文献   

3.
对襄樊市区孕妇尿碘含量进行了监测。监测结果:尿碘低于100μg/L者,30岁以上年龄组为高,达48.39%,9-11月季节组为高,达44.35%;7个月以上的孕期组为高,达30.64%,农民缺磺情况远远高于工人(26.07%)、干部(22.3%)、商人(15.98%),其尿碘平均含量低于100μg/L者,高达40.45%,为各职业之冠,可见孕妇尿碘含量监测的重点应是病区农民。  相似文献   

4.
为了解甲状腺肿大率与尿碘“分离”现象产生的原因 ,用B超检查甲状腺肿大率 ,用酸消化砷 -铈接触法测定尿碘 ,用直接滴定法测定盐碘。结果表明 ,全市甲状腺肿大率为 7 1% ;尿碘中位数为 2 0 5 5 μg/L ,盐碘中位数为 43 4× 10 -6。甲状腺肿大率与尿碘水平无明显相关性 ,与盐碘浓度也无差异显著性。提示出现病情与尿碘分离现象 ,可能存在其它致甲肿的原因。  相似文献   

5.
石墨炉原子吸收光谱法测定尿镉   总被引:8,自引:1,他引:8  
采用磷酸作为基体改进剂,石墨炉原子吸收光谱法测定了尿镉,其检测限为0.07μg/L,标准曲线线性范围0.0-5.0μg/L回收率99.91%,方法准确、简便、快速、污染少。  相似文献   

6.
应用高效的流动注射在线离子交换预浓集火焰原子吸收光谱测定系统直接测定了人尿中痕量镉。选择200μL锥形离子交换柱,内装多孔玻璃固定化的8-羟基喹啉离子交换剂,在pH9条件下样品流速为3.5mL/min,40s装样,用2mol/LHCl洗脱,在分析速度为60样/h,获得30倍的富集倍率。检出限为0.3μg/L。镉含量水平为40μg/L的尿样,连续测定11次的相对标准偏差为1.5%。尿标准参考物...?  相似文献   

7.
过碘酸钾氧化鸡冠花红动力学光度法测定食品中痕量碘   总被引:16,自引:0,他引:16  
张爱梅  王术皓 《分析化学》1998,26(8):967-969
基于硫酸介质中,草酸钠作活化剂,碘催化过碘酸钾氧化鸡冠花红而使其褪色的反应,建立了测定痕量碘的新方法。方法灵敏、简便、选择性好。测定碘的线性范围为0-20μg/L;检出限为0.66μg/L。用于食品中痕量碘的测定,结果满意。  相似文献   

8.
金同顺  贝源 《分析化学》1996,24(3):360-363
研究了一种小型同心氢化物发生配置一个气液分离器后与多道ICP-AES联用,同时测定水和生物样品中砷、铋、锑、硒的方法。检出限为砷0.4μg/L,铋0.5μg/L,锑1.4μg/L,硒0.5μg/L,相对标准偏差为砷2.7%,铋1.5%,锑2.7%,硒1.9%。用本法测定美国和国家标准物质中的氢化元素,结果满意。  相似文献   

9.
重庆地区食盐加碘含量下调的可行性研究   总被引:1,自引:0,他引:1  
为探讨重庆市食盐加碘含量下调的可行性,分析比较了重庆市碘盐和碘缺乏病监测结果(儿童甲状腺肿大率、智商、尿碘、家庭食用碘盐)。结果表明,碘盐含量稳定,全民食盐加碘防治碘缺乏病的措施成功,但尿碘水平高于适宜水平,甲肿率居高不下,可能存在补碘过量,引起高碘性甲状腺肿大。为有效控制甲肿率和尿碘水平,建议下调食盐加碘含量。  相似文献   

10.
氯胺T氧化孔雀绿动力学光度法测定食品中痕量碘   总被引:18,自引:0,他引:18  
李建国  乔艳  魏永前 《分析化学》1999,27(9):1072-1075
基于在稀土盐酸介质中,碘催化氯胺T氧化孔雀绿而使其褪色的反应同效毛细管建立了测定痕量碘的新方法。测定碘的线性范围为0 ̄80μg/L;检出限为1.6μg/L,方法灵敏、简便、选择性好,用于食品中靖量碘的测定,结果满意。  相似文献   

11.
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.  相似文献   

12.
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。  相似文献   

13.

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.

  相似文献   

14.
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.  相似文献   

15.
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。  相似文献   

16.
翟宗玺  刘树深  夏树屏 《化学学报》1990,48(10):946-950
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^-。  相似文献   

17.
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.  相似文献   

18.
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, Mo, 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 600-700oC. 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.  相似文献   

19.
袁丽秋 《化学教育》2006,27(5):8-10
面对日益枯竭的能源危机,氢能是一种洁净、最有前景的替代能源。目前在各种制氢的方法中光催化分解水制氢的研究最多,光解水过程中催化剂最关键,本文对利用太阳能光解水的途径、提高光催化反应效率以及光催化剂的开发研究进行了综述。  相似文献   

20.
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