NONHYDROCARBON AND NOBLE GAS GEOCHEMISTRY IN NATURAL GAS OF EASTERN CHINA

The isotopic composition of 15 natural gas samples, which were collected from northern Jiangsu Province, south Songliao, Sanshui County of Guangdong Province, have been analysed in terms of δ~(13)C of CO_2 and CH_4, δD of CH_4, δ~(15)N of N_2, ~3He/~4He, ~(40)Ar/~(36)Ar and R/R_A. Based on the isotopic and chemical composition of the natural gas and the geological background of these areas, such aspects as the genesis of nonhydrocarbon gas, geochemical characteristics of noble gases by contrast with the data of Sichuan Province~([1]), the Xinjiang Autonomous Region and the Yaojie Coal Mine of Gansu Province are discussed. It is pointed out that hydrocarbon and nonhydrocarbon gases reservoired in the same stratum may be of different genesis and that the helium of He-rich gas pool of Huangqiao, northern Jiangsu is closely related to the mantle, and is of the mantle degasification. It is an example of commerical gas pool that helium was accumulated in sedimentary beds. The He and CO_2 of Wanjinta at the     

气相色谱法与麻油纯度试验法在芝麻油掺伪鉴定中的应用

用气相色谱法和麻油纯度试验法对芝麻油掺伪情况进行分析。用气相色谱法分析脂肪酸组成,测定植物油中的主要脂肪酸,来确定是何种油或掺入其它何种植物油;麻油纯度试验法用于定量。两者可结合起来使用。     

TECTONIC FRAMEWORK OF THE CONTINENTAL BASEMENT OF SOUTHEAST CHINA

The chronology and tectonic evolution model of the continental basement in southeast China margin is an important debatable geological subject. The Cathaysia is shown in this paper to be in accordance with many geological facts and also with the age data obtained by multi-dating method. Its age has been determined to range from 900 to 2000 Ma. The age of the unconformity plane in the Cathaysia is 1400 Ma. The collision and suture between the Jiangnan oldland and the Cathaysia took place during the early Jinning Period. Toward Jiangxi, Hunan, Guangdong and Guangxi, these two continents gradually opened to form a residual oceanic basin. The sedimentation centre of the basin continuously migrated southwestward from the Jinning through the Caledonian Period, and finally closed in the Guangxi Movement and Dongwu Movement. The drift-rotation of the Cathaysia after the Jinning Period has been inferred.     

毛细管气相色谱法测定深海鱼油中的EPA和DHA含量

用氢氧化钾－甲醇酯化法将深海鱼油中的脂肪酸快速、有效地转化成脂肪酸甲酯,然后进行毛细管气相色谱法测定,以二十二碳饱和脂肪酸甲酯为内标物,建立了5,8,11,14,17－二十碳五烯酸（EPA）和4,7,10,13,16,19－二十二碳六烯酸（DHA）的定量分析方法,并用于实际样品分析。该方法对EPA和DHA定量分析的相对标准偏差分别为4．6％和5．0％,回收率分别为99．7％和99．4％。     

当前我国放射性核素迁移的实验研究

本文综述了当前我国放射性核素主要是锶铯碘铀的迁移研究，并指出了今后的发展方向。     

毛细管气相色谱法测定食用油中的酚类抗氧化剂BHA、BHT、TBHQ

建立了同时测定植物油中BHA、BHT、TBHQ等3种酚类抗氧化剂的测定方法。样品中的抗氧化剂经石油醚提取、乙腈萃取后采用HP-5毛细管柱分离。样品加标回收率为82.8?.6%,相对标准偏差为1.06%~3.11%,BHA、BHT、TBHQ的最低检出量分别为5、10、5ng。该方法具有快速、灵敏度高、重现性好、前处理简单等优点。     

MICROFOSSILS FROM LATE PROTEROZOIC MANGANESE ORE DEPOSITS IN WESTERN HUNAN PROVINCE AND EASTERN GUIZHOU PROVINCE, SOUTH CHINA

Abundant microfossils and organic residuals have been discovered by SEM and normal palynological maceration from manganese ore beds intercalated in late Proterozoic glacial rock units in western Hunan Province and eastern Guizhou Province. Taking isotopic dating into consideration, the age of manganese ore deposits in both regions is suggested to be about 750 Ma. A distinct character is that a great quantity of colonial microfossil——Sphaerocongregus (or Bavlinella) and their degradational variants have been obtained from rhodochrosite. Their biological and biochemical functions, combined with the geochemical effect of manganese in different ways, may play an important role in the manganese cycle.     

溶出伏安法连续测定粮油制品中营养强化剂锌和铁

研究了在ｐＨ４．８介质中,锌和铁在ＨＯＡｃ－ＮａＯＡｃ底液中各产生一个灵敏吸附波的最佳条件。应用于连续测定粮油制品中强化剂锌和铁含量,方法简便、快速,灵敏度、回收率均较高。     

反相高效液相色谱法测定油脂中抗氧化剂特丁基对苯二酚

采用反相高效液相色谱法分离并测定了加入于油脂中的抗氧化剂t-丁基对苯二酚 (t-BHQ)。适量的油脂试样溶于n-已烷中,其中的t-BHQ用甲醇萃取。含有t-BHQ的甲醇溶液进样至仪器中进行分离和测定。采用Symmetry Shield RP-C18作固定相;流动相系由甲醇及 0．001 mol·L-1磷酸按60比40的体积比混合配成,并用0．001 mol·L-1乙酸及0．001 mol·L-1 磷酸组成的缓冲控制流动相的酸度至pH 5．0。t-BHQ浓度在0．010 07-0．402 8 g·L-1范围内与所测主峰面积之间呈线性关系。方法的检出限(S／N=2)为0．020 14 μg。无论日间或日内测定的保留时间值或峰面积值,计算所得的RSD值均小于3．4％,说明仪器的重复性和稳定性良好。回收试验的结果表明测定的回收率在91．8％-94．0％之间,一次分析仅需6 min。     

裂化气、乙炔尾气及产品乙炔中H_2S、CS_2的测定

原料天然气常含有300mg/m~3以上的硫化氢、甲硫醇、乙硫醇、甲硫醚、乙硫醚等硫化物,经脱硫精制处理后,仍有少量硫化物转入到裂化气、尾气、产品乙炔中。这些硫化物的存在对甲醇合成触媒和醋酸乙烯合成触媒均有不利影响。因此,硫化物的检测对生产控制极为     

STUDY ON COAL-BED GAS COMPOSITIONS AND ITS GEOCHEMICAL CHARACTERISTICS IN CHINA

This paper considers, through a lot of measured data of coal-bed gas, that the coal-bed gas is a kind of mixed gas of complex composition with some heavy hydrocarbons. In general, it is not a dry gas. The coal-bed hydrocarbon gases can obviously be divided into three stages of gas-storage: "poor hydrocarbon-storing stage", "rich hydrocarbon-storing stage" and "declining hydrocarbon stage". Authors point out that the normal gas geochemical indexes can relatively well show the geochemical chatacteristics of coal-bed gas. But, "the Benzene Index (B)" is a good indicator to identify the gas original types, and "the Hexane Index(H)" can show the gas evolution law and the organic matter maturity.     

CLAY MINERALS IN THE CHINA SEA AND ADJACENT SEAS

The clay minerals in the surface sediments from 354 stations have been analyzed qualita-tively and semiquantitatively. The obtained data are dealt mathematically. According to thecalculated results, the distribution laws and the trends of content changes of clay mineralsare discussed. The studied area is divided into four main provinces of sediments with differ-ent sources. Finally the author approached the laws of the migration and dispersal of thefine-grained matter carried into the seas by the Huanghe River, the Changjiang River, theZhujiang River and the Philippine Archipelagoes, and set up the transport model of the fine-grained matter in the China Sea and adjacent seas.     

气相色谱质谱法测定植物油中脂肪酸

建立了气相色谱质谱法测定食用植物性油中脂肪酸检测的方法。植物油中的脂肪酸甘油酯在碱性条件下被水解为游离脂肪酸,随后采用三氟化硼将其转化为脂肪酸甲酯。采用同位素标记脂肪酸进行加标回收试验,回收率在94%以上。通过质谱的选择离子检测模式对硬脂酸、油酸、亚油酸等10种目标脂肪酸进行了检测,结果显示,该方法可用于油品的质量检测和日常分析。     

气体基本定律在建立气体测量仪计量检定装置中的应用

遵循道尔顿定律建立的双压力法恒湿气体发生器,各项技术指标高于湿度计量一等标准要求,可用于校准和测量湿度仪器及测湿元件;遵循理想气体状态方程及静态容积法配制乙醇标准气体,建立的呼出气体酒精含量探测器检定装置,其不确定度优于被检探测器允许相对误差的三倍以上,可以满足呼出气体酒精含量探测器检定的需要。     

毛细管气相色谱法同时测定白酒中的甲醇和杂醇油

采用PEG20000石英毛细管柱直接进样、氢火焰离子化检测器检测,建立了毛细管气相色谱同时测定白酒中的甲醇和杂醇油的分析方法。甲醇和杂醇油的检出限均为2.0×10-4g/(100mL),回收率分别为96.4%~99.1%、91.2%~98.3%,相对标准偏差不大于4.3%。该方法适用于白酒中甲醇和杂醇油的同时分析测定。     

气相色谱-质谱联用分析茶树油的成分

采用常规水蒸气蒸馏法从茶树枝叶中提取茶树油，经气相色谱-质谱联用分析，分离出47种成分，检索NI蚋8质谱数据库，与标准谱图对照鉴定了其中32种成分。应用Hewlett—Packard软件，按峰面积归一化法定量，所鉴定成分的馏出峰面积占总馏出峰面积的96．08％。     

吹扫捕集气相色谱法测定水中苯系物

采用吹扫捕集-气相色谱法测定生活饮用水中苯系物(笨、甲苯、乙苯、邻、间、对二甲苯、异丙苯、苯乙烯),并对吹扫捕集的条件进行优化,缩短了分析周期,提高了方法的灵敏度和准确度.方法的最低检出浓度为0.9～1.7μg/L,相对标准偏差为0.63%～1.36%(n=7),平均加标回收率为97.4%～101.3%.本方法适合于地表水和生活饮用水中苯系物的测定.     

气相色谱法分析尿液样品中阿特拉津及其代谢物

建立尿液样品中阿特拉津(ATZ)及其代谢物脱乙基阿特拉津(DEA)、脱异丙基阿特拉津(DIA)、脱乙基脱异丙基阿特拉津(DEDIA)的气相色谱分析方法。样品通过乙酸乙酯萃取,硫酸钠干燥,弗罗里硅土净化,浓缩后用气相色谱ECD检测器分析。对方法中pH值等条件进行了优化,获得了较好的回收率。方法的检出限为DEDIA:2.5ng/mL,DEA、DIA、ATZ:均为5ng/mL。利用本方法对阿特拉津生产工人的实际尿液样品进行了分析。     

气体分析中的气相色谱技术展望

介绍气相色谱技术在气体分析中的应用,对气相色谱新技术进行了展望。     

吹扫捕集-气相色谱法测定水中苯系物

利用HP-Innowax毛细管色谱柱,对对二甲苯和间二甲苯进行了分离研究,并建立吹扫捕集-气相色谱法测定水中6种常见苯系物的方法。当水样进样体积为25mL时,方法检出限为0．08～0．30μg/L,用该方法对实际水样中的6种苯系物进行测定,回收率为69．0％～111.9％,测定结果的相对标准偏差均小于4％。