不同类型镜质体的气态烃碳同位素生成动力学

金管封闭体系热模拟条件下镜质体生烃动力学研究表明：活化能随镜质体类型、结构的不同而有很大差异．均质镜质体裂解活化能最高而基质镜质体活化能分布相对较低．而由不同类型镜质体裂解生成的甲烷均具有非常相似的碳同位素分布，热模拟早期δ^13C1随温度的升高而下降，晚期逐渐上升，更高温度热解时保持平衡或略有下降．由此可见镜质体的热解天然气碳同位素分馏主要受时间、温度及总碳同位素值的控制，而镜质体结构及活化能分布对碳同位素分馏影响较小．早期δ^13C1下降的趋势可能是由于镜质体的不均质性或在不同的活化能区间^12C-^12C及^12C-^13C之间的活化能差值(△E)有所不同造成的．     

微电解处理对染料废水脱色的影响

对微电解法处理染料废水进行了脱色实验。对停留时间、pH、铁碳比、染料废水初始色度、活性炭表面处理等因素进行分析。结果表明，在一定条件下，用微电解法处理色度为800的染料废水，色度的去除率可达90％以上。     

苦参碱在玻碳电极上的直接电化学行为及电分析方法研究

研究了生理介质中苦参碱在玻碳电极上的直接电化学行为,结果发现,在0.30～1.20V(相对于SCE)的电位窗口内及0.15mol/LNaCl水溶液中,苦参碱在0.92V附近产生了一个不可逆氧化峰,并且在一定条件下电极反应受扩散步骤控制.运用差分脉冲伏安法研究了苦参碱的峰电流与其浓度的关系,确定了浓度测定线性范围4.0×10-4～1.4×10-2mol/L,检测限为(4.0±0.02)×10-4mol/L.用该方法测定了相应药物中苦参碱的含量,相对偏差在0.6%以内,平均回收率为100.0%～101.0%,测定的精密度和准确度符合测定要求.     

土壤水分胁迫下大麦籽粒形成期碳氮代谢及其互作效应

利用防雨棚研究了土壤水分胁迫对大麦籽粒形成期碳氮代谢生理特性的影响。结果表明：淀粉和蛋白质沉积的生理机制的明显差异是导致干旱胁迫下籽粒淀粉沉积降低、蛋白质积累增加的内在因素；同时，籽粒形成后期的碳氮代谢互作在竞争和能量方面的差异也对籽粒淀粉沉积减少、蛋白质含量增加起到了一定的作用。     

羌塘盆地中晚侏罗世旋回地层初步分析

羌塘盆地是中国海相侏罗系最为发育的地区之一,对该套地层开展了旋回地层学研究,初步的研究结果表明羌塘盆地中上侏罗统至少存在四种旋回类型,即沉积旋回、古生物旋回、地球化学旋回和磁化率旋回,并按级别将低频旋回划分为3个旋回级次.其中一级旋回是由顶底不整合面限制的一个总体向上变粗变浅的充填序列,持续时间为48 Ma;二级旋回显示为大型的海进-海退旋回,旋回的时间跨度为27～29 Ma;三级旋回显示为向上变粗或向上变细的不完整旋回,旋回的时间跨度为7～14 Ma.古生物旋回、地球化学旋回(碳氧稳定同位素、微量元素)和磁化率旋回与沉积旋回具有良好的响应,并与特提斯同期低频旋回具有很好的对比性.     

CaO对CaO-Al_2O_3-SiO_2系微晶玻璃析晶行为的影响

利用烧结工艺制备微晶玻璃以CaO Al2O3 SiO2三元系微晶玻璃为研究对象,通过DTA,XRD,SEM分析方法,对玻璃析晶动力学进行研究·利用Kissinger方程来计算微晶玻璃析晶转变的活化能E,发现随着氧化钙含量的增加,析晶温度降低,析晶活化能降低,并最终推导出析晶机理参数n=2,体系属于整体析晶·实验结果发现:微晶玻璃的析晶相均为硅灰石结构;氧化钙含量的增加有利于微晶玻璃的晶化,但表面缺陷更明显,如:坑点、突起、断裂等·     

广州夏季大气中碳气溶胶浓度水平及污染特征

2002年6-7月于广州市3个采样点采集PM10和PM25样品,测定了PM10,PM25以及元素碳(EC)和有机碳(OC)的浓度.PM10和PM2.5平均浓度分别为124.77μg@m-3及78.13μg@m-3.PM10和PM2.5中的OC浓度分别为22.3μg@m-3和15.80μg@m-3,EC浓度分别为7.78和5.90μg@m-3,其中73.8%的OC和77.7%的EC存在于PM25中.在3个采样点PM10和PM25中,OC/EC比值均大于2.0,表明广州夏季大气存在二次污染.各种气象条件对OC、EC浓度及其比值的变化都有不同程度的影响,其中降水和风速是OC、EC浓度变化的主要气象因素.     

SEM analysis of the changes of carbon layer structure of mesocarbon microbeads heat-treated at different temperatures

Mesocarbon microbeads (MCMB) with narrow size distribution, excellent sphericity and no obvious conglutination have been prepared with a coal tar pitch containing quinoline insolubles (QI) as the raw material. Optical microscopy and scanning electron microscopy (SEM) are used to examine the structure of the MCMB. It has been found that SEM technique shows the structural information of MCMB clearly in the form of micrographs even when the structure of MCMB is complex, while the optical technique is useful for analysis of the regular structure of the mesophase spheres but cannot be effectively used to analyze either the complex structure of the green MCMB or the structures of the further heat-treated ones at different temperatures. According to the characteristics of the carbon layers, the structures of the as-prepared MCMB in the present experiment could be classified as (I) Parallel Layer type structure and (2) Bent Layer type structure with the carbon layers gathering at one or two points in the MCMB. In the experiments, SEM is also utilized to investigate the structures of MCMB that are heat-treated at different temperatures. It has been found that the MCMB without any further heat-treatment show no layered-carbons, while the ones heat-treated at temperaturehigher than 1000℃ exhibit obvious layered carbons across their sections. When increasing the heat-treatment temperature, the carbon layers become thinner and flatter.     

Analysis of carbon isotopes in airborne carbonate and implications for aeolian sources

Methods were developed to determine the mass ratios of carbon isotopes in trace amounts of aerosol carbonate. A Finnigan MAT 252 mass spectrometer fitted with an on-line Kiel device was to determine the ^13C/^12C ratio in CO2 produced from the carbonate. A study using these methods was conducted to characterize the carbonate carbon isotopes in aerosol samples collected in Xi‘an on dusty and normal days during March and April 2002. Results of the study demonstrate that insights into the origin of the dust can be deduced from its isotopic composition. That is, the δ^13C ofcarbonate for dust storm samples ranged from -1.4‰ to -4.2‰, and this is consistent with sandy materials in dust source regions upwind. In contrast, for non-dusty days δ^13C ranged from -7.5% to -9.3‰, which is more similar to fine particles emitted from local surface soils. Comparisons of dust storm aerosols with surface soils from source regions and with aerosol samples collected downwind indicate that the δ^13C values did not change appreciably during longrange transport. Therefore, carbon isotopes have the potential for distinguishing among source materials, and this approach provides a powerful new tool for identifying dust provenance.     

陶瓷玻璃餐具出台新规定

《环境标志产品认证技术要求》对与食物接触的陶瓷、微晶玻璃和玻璃餐具制品作了如下定义:陶瓷为由黏土及长石、石英等天然原料经混合、成形、干燥和烧制而成的耐水、耐火、坚硬的材料和制品的总称,包括陶器、瓷器和炻器等。微晶玻璃为在高温条件下将原材料熔化为均匀的液体,冷