夏季东海一氧化碳的浓度分布、海-气通量和微生物消耗研究

研究了夏季东海海水中和大气中一氧化碳(CO)的浓度分布、海-气通量和表层海水中CO的微生物消耗。夏季东海大气中CO的体积分数范围为63×10-9~120×10-9,平均值为87×10-9(SD=18×10-9,n=37),呈现出近岸高,远海低和北高南低的特点。夏季东海表层海水中CO的浓度范围为0.24~5.51nmol/L,平均值为1.48nmol/L(SD=1.46,n=37),CO的浓度受太阳辐射影响明显;CO在垂直分布上表现出浓度随深度增加迅速减小的特征,浓度最大值出现在表层。调查期间表层海水中CO相比大气处于过饱和状态,过饱和系数变化范围为3.65~113.55,平均值为23.63(SD=24.56,n=37),这表明调查海域是大气中CO的源。CO的海-气通量变化范围为0.25~78.50μmol/(m2·d),平均值为9.97μmol/(m2·d)(SD=14.92,n=37)。在CO的微生物消耗培养实验中,CO的浓度随时间增长呈指数降低,消耗过程表现出一级反应的特点,速率常数KCO范围为0.043~0.32/h,平均值为0.18/h(SD=0.088,n=9),KCO与盐度之间存在负相关关系。     

Methane,carbon monoxide and methylchloroform in the southern hemisphere

New observational data on CH₄, CO and CH₃CCl₃ in the southern hemisphere are reported. The data are analysed for long term trends and seasonal cycles. CH₃CCl₃ data are used to scale the OH fields incorporated in a two dimensional model, which in turn, is used to constrain the magnitude of a global CH₄ source function. The possible causes of observed seasonality of CH₃CCl₃, CH₄ and CO are identified, and several other aspects of observed CH₄ variability are discussed.Possible future research directions are also given.     

民居CO中毒事件气象条件分析及数值模拟

应用伯努利原理和CFD应用软件FLUENT,对影响北方民居通风排烟和CO中毒事件的气象因子进行分析和数值模拟,研究基于气象条件的CO中毒事件预警方法。结果表明：影响民居通风排烟的气象条件主要有风速、气温（室内外温度差）、变压和相对湿度等。风速是影响通风排烟和CO中毒的主要气象因素;在弱风条件下,室内外温度差和气压的变化对通风排烟也有重要影响。在上述工作基础上,建立了民居通风排烟气象指数的计算方法和基于气象条件的CO中毒事件预警方法,经检验表明该方法对中毒事件有一定的预警能力。     

氯盐渍土土-水特征曲线的试验研究

采用滤纸法和压力板法测定不同含盐量盐渍土的土-水特征曲线（SWCC）,探讨土中含盐量对盐渍土土-水特征曲线的影响。试验结果表明,粉土中含盐量对基质吸力土-水特征曲线的影响不大。采用滤纸法测得的总吸力与基质吸力之间的差值随着土中盐溶液浓度的增加而增加,且该差值要大于相同浓度纯盐溶液的渗透吸力,其原因是由于土颗粒表面对溶液吸附作用引起的,用滤纸法测得的基质吸力土-水特征曲线处于脱湿曲线和吸湿曲线之间。采用蒸汽平衡法测定Whatman 42号滤纸在高吸力阶段的总吸力的率定曲线,使得高吸力时用滤纸法测定吸力更为精确。     

Cl/Br of scapolite as a fluid tracer in the earth's crust: insights into fluid sources in the Mary Kathleen Fold Belt,Mt. Isa Inlier,Australia

A combination of analytical methods, including trace element analysis of Br in scapolite by LA‐ICP‐MS, was employed to unravel the fluid–rock interaction history of the Mary Kathleen Fold Belt of northern Australia. Halogen ratios in the metamorphic and hydrothermally derived scapolite from a range of rock‐types record interaction between the host rocks and magmatic‐hydrothermal fluids derived from granite plutons and regional metamorphism. The results show that halite‐dissolution supplied at best only minor chlorine to fluids in the Fold Belt. Chlorine/bromine ratios in metamorphic scapolite indicate that fluids were dominantly derived from basinal brines formed from sub‐aerial evaporation of seawater beyond the point of halite saturation. This bittern fluid infiltrated the underlying sedimentary sequences prior to regional metamorphism. Zoned scapolite in a major late metamorphic mineralized shear‐zone records three discrete pulses of magmatic and metamorphic fluid, and it is suggested that fluid mixing may have assisted mineralization along and around this shear‐zone. As a crucial prerequisite for halogen fluid tracer studies using scapolite, we find in our samples that Cl and Br do not fractionate when incorporated in scapolite. Furthermore, unaltered rims of heavily retrogressed scapolite show indistinguishable Cl/Br signatures compared with fresh grains from the same sample indicating retrograde metamorphism did not significantly affect Cl and Br signatures in scapolite group minerals.     

柴达木盆地氯同位素组成特征

采用正热电离高精度测定Ｃｌ同位素的方法对我国柴达木盆地水体及盐类沉积的Ｃｌ同位素组成进行了精确测定，结果表明，柴达木盆地Ｃｌ同位素组成存在着明显的变化。各种水体的平均δ＾３７Ｃｌ值顺序为：河水（０．９４‰）〉咸水湖水（－０．２‰）〉油田水（－０．６２‰）〉盐湖卤水（－０．９７‰）。卤水具有低的δ＾３７Ｃｌ值，这是盐湖卤水蒸发析盐的结果。盐湖卤水与共存盐类矿物间的分馏系数为１．０００１－１．００２１     

鄂尔多斯白垩系盆地地下水的形成与演化：来自Cl及其同位素36Cl的证据

鄂尔多斯自垩系地下水盆地地处中国西部干旱-半干旱地区,其南部和北部分别被黄土和沙漠覆盖,地下水水化学组成在区域上差异显著,北部以淡水为主,南部以微咸-半咸水为主.在沙漠区和黄土区的深层含水层中(埋深大于400 m)分别采集了5组和3组水化学同位素样品.T和14C的分析结果表明,地下水的滞留时间在20343 a内,并且未...     

稳定氯同位素地球化学研究进展

地球卤素元素含量相对稀少,相对而言氯为最常见的卤素元素。氯是一种挥发性元素,具有强烈的亲水性。自然界氯两个稳定同位素³⁵Cl和³⁷Cl,其相对丰度分别为75.76%和24.24%。文章综述了氯在各个地质储库的特征、稳定氯同位素分馏的控制因素以及氯同位素的地质应用三大方面的研究进展。地球主要储库中蒸发岩、海水、岩浆岩、沉积物、变质岩、地幔的氯同位素组成分别为-0.5‰~+0.8‰、0.00±0.05‰、-1.12‰~+0.79‰、-3.0‰~+2.0‰、-3.6‰~0、-1.9‰~+7.2‰。地外(月球、火星及其他小行星4-Vesta)氯同位素组成变化范围分别为-4‰~+81.1‰、-5.6‰~+8.6‰、-3.8‰~+7.7‰。相对地球上氯同位素(δ³⁷Cl)的变化范围(-14‰~+16‰),月球和火星δ³⁷Cl的变化范围可达-5.6‰~+81‰,表明挥发分氯在地内和地外迁移循环过程中有显著不同同位素分馏主控机制。已经探明氯同位素分馏受控于物理过程(如扩散、离子过滤、沉淀溶解作用、火山作用)和化学作用(如水岩作用、变质作用,尤其是蛇纹石化作用)等。扩散作用、淋滤作用和火山作用富集重同位素,沉淀作用结晶盐δ³⁷Cl先减小后上升,而蛇纹石化过程中多种因素共同影响。与其他指标结合,氯同位素地球化学可用于有效指示钾盐矿床远景区,评估示踪地下水的来源和演化路径、示踪污染物源区和量化生物修复、探究矿化流体来源、指示行星演化岩浆海洋脱气等过程。     

The F,Cl, Br and I Contents of Reference Glasses BHVO‐2G,BIR‐1G,BCR‐2G,GSD‐1G,GSE‐1G,NIST SRM 610 and NIST SRM 612

Halogen contents for the widely distributed reference glasses BHVO‐2G, BIR‐1G, BCR‐2G, GSD‐1G, GSE‐1G, NIST SRM 610 and NIST SRM 612 were investigated by pyrohydrolysis combined with ion chromatography, total reflection X‐ray fluorescence analysis, instrumental neutron activation analysis, the noble gas method, electron probe microanalysis and laser ablation‐inductively coupled plasma‐mass spectrometry. Glasses BHVO‐2G, GSD‐1G and GSE‐1G have halogen contents that can be reproduced at the 15% level by all bulk techniques and cover a significant range in halogen mass fractions for F (~ 20–300 μg g^?1), Cl (~ 70–1220 μg g^?1) and Br (~ 0.2–285 μg g^?1) and I (~ 9–3560 ng g^?1). The BIR‐1G glass has low F (< 15 μg g^?1), Cl (~ 20 μg g^?1), Br (15 ng g^?1) and I (3 ng g^?1). The halogen contents for the silica‐rich NIST SRM 610 and 612 glasses were poorly reproduced by the different techniques. The relatively high Cl, Br and I abundances in glasses GSD‐1G and GSE‐1G mean that these glasses are well suited for calibrating spatially resolved micro‐analytical studies on silicate glasses, melt and fluid inclusions. Combined EPMA and laser ablation‐inductively coupled plasma‐mass spectrometry data for glass GSE‐1G demonstrate homogeneity at the 10% level for Cl and Br.     

X射线荧光光谱法测定地质样品中的氯和硫

使用粉末压片-X射线荧光光谱法测定地质样品中的Cl和S，探讨了样品放置时间、环境以及建立真空的时间对测量结果的影响。Cl的精密度(RSD，n=6)小于10％，S的精密度(RSD，n=6)小于5％。Cl和S的方法检出限分别为14和11μg／g，采用国家标准物质分析验证方法，其结果与标准值相符。