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71.
本文以离子膜电解氯化钾制取碳酸钾工艺产生的淡盐水为原料,系统地研究了聚四氟乙烯平板型气态膜回收氯过程中膜性能和次氯酸钠水溶液的制备。初步研究表明,次氯酸钠含量大于100g/L,氢氧化钠有效利用率为90%;聚四氟乙烯膜有传质快、对离子截留性能好、使用寿命长等优点,在工业上有较好的应用前景。 相似文献
72.
G. A. Herbert R. C. Schnell H. A. Bridgman B. A. Bodhaine S. J. Oltmans G. E. Shaw 《Journal of Atmospheric Chemistry》1989,9(1-3):17-48
The second Arctic Gas and Aerosol Sampling Program (AGASP-II) was conducted across the Alaskan and Canadian Arctic in April 1986, to study the in situ aerosol, and the chemical and optical properties of Arctic haze. The NOAA WP-3D aircraft, with special instrumentation added, made six flights during AGASP-II. Measurements of wind, pressure, temperature, ozone, water vapor, condensation nuclei (CN) concentration, and aerosol scattering extinction (bsp) were used to determine the location of significant haze layers. The measurements made on the first three flights, over the Arctic Ocean north of Barrow and over the Beaufort Sea north of Barter Island, Alaska are discussed in detail in this report of the first phase of AGASP II. In the Alaskan Arctic the WP-3D detected a large and persistent region of haze between 960 and 750 mb, in a thermally stable layer, on 2, 8, and 9 April 1986. At its most dense, the haze contained CN concentrations >10,000 cm–3 and bsp of 80×10–6 m–1 suggesting active SO2 to H2SO4 gas-to-particle conversion. Calculations based upon observed SO2 concentrations and ambient relative humidities suggest that 104–105 small H2SO4 droplets could have been produced in the haze layers. High concentrations of sub-micron H2SO4 droplets were collected in haze. Ozone concentrations were 5–10 ppb higher in the haze layers than in the surrounding troposphere. Outside the regions of haze, CN concentrations ranged from 100 to 400 cm–3 and bsp values were about (20–40)×10–6 m–1. Air mass trajectories were computed to depict the air flow upwind of regions in which haze was observed. In two cases the back trajectories and ground measurements suggested the source to be in central Europe. 相似文献
73.
Methods for the determination of three compound classes, i. e. diaminotoluenes, nitrophenols, and chloroaromatics in groundwater of a former ammunition plant are reported. Diaminotoluenes were extracted by discontinuous liquid/liquid-, nitrophenols by continuous liquid/liquid-extraction using dichloromethane, and chloroaromatics by solid-phase extraction. These compound classes may be analyzed by gas chromatography (GC) or gas chromatography coupled to mass spectrometry (GC/MS) without derivatization or after derivatization with N-methyl-bis(trifluoroacetamide) (MBTFA) or heptafluorobutyric anhydride (HFBA) in the case of diaminotoluenes and HFBA or acetic anhydride in the case of nitrophenols. An atomic emission detector (AED) coupled to a gas chromatograph may be employed for the analysis of chloroaromatics. High selectivity can be achieved using the characteristic wavelengths of chlorine. A variety of these compounds were identified and quantified in a groundwater sample from the former ammunition plant Elsnig (Saxony, Germany). Concentrations were in the lower ppb range. Thus, dichlorobenzenes which may have been used as substituents at the end of World War II could be identified in groundwater samples at this site. 相似文献
74.
Recent improvements in both Infra-red spectroscopy and equilibrator techniqueshave allowed to determine, for the first time, pCO2using simultaneously and continuously both the direct and indirect methods in an estuary where pCO2 values range from 500 to 8500 atm and salinity from 0 to 30. Our results show that both methods are in excellent agreement in the wholeestuary (r2 = 0.999, n = 1075, p < 0.0001). Thus, the NBS (US National Bureau of Standards) scale, although inadequate for seawater samples, is appropriate for estuarine waters and can be applied with confidence to calculate pCO2. 相似文献
75.
加油站的雷电防护设计 总被引:7,自引:1,他引:7
通过对加油站所处环境特点、系统特点中雷电灾害各因素的分析,对加油棚、油罐及附属建筑的直击雷防护和接地,加油站电源、信号系统的雷电系统防护和静电防护等,依据GB50057、IEC61312、GB50156—2002标准对雷电防护的要求,提出了系统的解决方案。 相似文献
76.
沉积物粒度对水合物形成的制约:来自IODP 311航次证据 总被引:1,自引:0,他引:1
对取自IODP 311航次(东北太平洋Cascadia大陆边缘)所有5个站位、采样间距约为1.5 m的614件沉积物样品,利用Beckman Coulter LS 230激光粒度仪进行了沉积物粒度分析,获得了沉积物粒度随深度变化特征,进而与水合物层位的替代指标进行了位置对比,这些指标包括特殊沉积构造(soupy和mousse like构造)、测井数据(LWD)推算出来的水合物饱和度(Sh)、岩芯红外图像和实际钻取的含水合物沉积物等。发现沉积物粒度分别为31~63 μm和63~125 μm的2组较粗粒径的沉积物数量变化增多的位置与水合物出现层位之间存在较好的位置对应关系。如在U1326站位海底以下5~8 m、21~26 m、50~123 m、132~140 m、167~180 m、195~206 m、220~240 m深度位置出现了沉积物粒度明显偏向粗粒的趋势,而这些位置正好对应于大多数特殊沉积构造出现的深度,也对应于水合物饱和度(Sh)值相对较高的深度,并与一些实际钻取的赋含水合物的浊积沙层观察结果一致。因此,初步研究后认为,沉积物粒度在水合物形成过程中扮演了重要角色,天然气水合物可能偏向形成于粒度大于31 μm的粗粒沉积物中。
相似文献
77.
Recent Geochemical Variation of the Hot-Spring Gases from the Tianchi Volcano, Changbai Mountains, Northeast China 总被引:1,自引:0,他引:1
Recent fluid monitoring work shows that the contents of mantle-derived CO_2,He and CH_4 increased anomalously in 2002 and 2003. The 3He/4He ratio of the deep-fault-type Jinjiang hot springs increased highly anomalously in 2003, and then decreased in 2004. The 3He/4He ratio from the thermal-reservoir-type Changbaijulong hot springs increased slowly in 2003, and the increase continued in 2004. The mantle-derived He content of the He released from the Changbaijulong springs increased obviously in 2004. The anomaly of the released gases and the isotopic He was consistent with the trends of seismic activities in the Tianchi volcanic area between 2002 and 2004. The abnormal release of the Jinjiang hot springs apparently decreased after the seismic activities ceased in the second half of 2004, while the abnormal release from the Changbaijulong increased significantly after these seismic activities. It shows that the abnormal release of magmas-derived gases from the thermal-reservoir-type springs lags behind that of the deep-fault-type springs. These characteristics may be of great significance for identifying deep magmatic activity and predicting volcanic earthquakes in the future. 相似文献
78.
日本南海海槽天然气水合物研究现状 总被引:8,自引:3,他引:8
本文介绍日本在其周围海域特别是南海海槽的海洋天然气水合物研究工作,首先介绍其研究简史,研究计划,研究队伍及早期研究成果,其次,介绍了西南海海槽天然气水合物的勘探、研究状况,然后,介绍了五年计划实施的东南海海槽地球物理勘探、钻探状况,最后指出,南海海槽的一些新资料深入的综合研究无疑会给世界水合物研究增添新的内容。 相似文献
79.
80.
天然气水合物的地热研究进展 总被引:8,自引:0,他引:8
天然气水合物的地热研究在以下几个方面都取得了重要进展,热流与似海底反射层的关系,水合物稳定带的研究;水合物热物理参数的确定;水合物形成过程中的热状态;热导率的应用,指出了今后水合物的地热学研究方向。 相似文献