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611.
Weak growth in industrial (nonagricultural) U.S. sulfur demand has slowed the growth of total sulfur demand. Evaluating prospects for trend reversal is hampered by inadequate detailed data published by industry, and the lack of an easily measured demand component that reliably depicts total demand. In this article, I try to overcome this data deficiency by constructing an industry-by-industry breakdown of published data on total industrial sulfur consumption. Industrial sulfur consumptions were estimated from data on consuming industry activity, characteristics of relevant industrial processes, and analyses of the conditions affecting choice among alternative industrial processes. Subjective projections of the industry detail data are presented.In addition to cyclical factors, past declines in industrial sulfur demand were due to replacement of sulfur-using industrial processes with alternative processes that use less or no sulfur to achieve production cost economies. In some, but not all, cases, changeovers of process were in response to impositions of environmental-related requirements. The demand for industrial sulfur has good prospects for positive growth as shrinkage of some markets reaches natural limits and total market growth comes increasingly to be dominated by markets with positive growth prospects. Positive growth has been generated by environmentally related regulation in several markets, such as petroleum alkylation and copper production.  相似文献   
612.
于伯杉 《盐湖研究》1994,2(2):70-75
渗透蒸馏是适用于浓缩生物制品的一种新型膜过程.以NaCl—柠檬酸稀溶液为研究体系,对渗透蒸馏的传质过程进行了研究,实验结果表明,水通量大于67Kg/m2·d,柠檬酸可由300g/L浓缩到500g/L以上,同时还探索了渗透蒸馏和膜蒸馏浓缩柠檬酸的集成膜过程.  相似文献   
613.
黑龙江省冷硅锶质矿泉水赋存规律和形成机制的探讨   总被引:1,自引:0,他引:1  
近年来,黑龙江省境内发现了多处含硅质或硅锶质天然矿泉水,这种矿泉水属珍贵的矿泉水类型之一。本文就冷硅或硅锶质矿泉水的赋存规律和形成机制提出初浅认识。  相似文献   
614.
溶胶-凝胶法制备纳米氧化镁研究   总被引:4,自引:0,他引:4       下载免费PDF全文
以硝酸镁和硬脂酸为原料,用溶胶—凝胶(Sol-Gel)法制备得到了纳米氧化镁微粒,并用热重(TG)分析、X-射线粉末衍射(XRD)、红外光谱(IR)和透射电镜(TEM)等对该纳米微粒的结构与形貌进行了表征。结果表明,控制Mg(NO3)2和CH3(CH2)16COOH物质的量比为1∶4,在90℃反应20 min并于360℃热处理4 h,得到立方相氧化镁纳米微粒,形貌为椭球体,分散性好,平均粒径约为33 nm。  相似文献   
615.
Abstract. Sandstones with high reservoir quality occur in the Paleogene and Upper Cretaceous coal measures off Sanriku and Sohma in the Pacific coast of northeast Honshu. The sandstone porosity was generally produced by the dissolution of calcite cement and clastic grains such as feldspar and glassy volcanics. The most probable cause of dissolution is the organic acids generated from the maturation of coal and coaly matter in the deeply subsiding source area prior to thermogenic hydrocarbon generation. The pore fluid including organic acids dissolved calcite and clastic silicates to form a small amount of laumontite and kaolinite at around 60C. The acidic and not neutralized pore fluid was responsible for the formation of kaoli-nite. On the other hand, laumontite was formed when the acidic pore fluid was neutralized and then made alkaline after the reaction with minerals such as plagioclase, glassy volcanics and calcite cement. Therefore, laumontite and kaolinite generally occur separately. Laumontite is 0.6–4.6 % by volume, whereas kaolinite is 0.6–9.8 % and the sandstone porosity remains from 10 to 22 %. This type of laumontization after the secondary pore formation might not give a severe damage to the reservoir property of the Paleogene and Upper Cretaceous coal measures in the Pacific coast of northeast Honshu and indicates further exploration possibility.  相似文献   
616.
粘土对丙烯基复合吸水树脂性能的影响研究   总被引:6,自引:0,他引:6  
以丙烯酰胺(AM)、丙NN(AA)为原料,以不同粒径的粘士(MMT)为无机填料采用水溶液聚合法合成了复合吸水树脂,讨论了MMT对其吸水性、保水性、韧性、抗温性、抗盐性的影响及其影响机理。结果表明,MMT的粒径越小,吸水树脂吸水倍率越低,韧性、抗盐性、抗温性等性能就越好;可通过调整MMT粒径来提高树脂的综合性能。  相似文献   
617.
Heike Koppitz   《Limnologica》2004,34(1-2):37
Changes in the contents and composition of dissolved amino acids and carbohydrates were monitored in different Phragmites australis stands in Germany. Four different reed clones planted in 1997 in a degraded fen area in NE-Germany were compared with respect to the seasonal development in the total amount of amino acids and sugars in the basal culm internodes. The individual Phragmites clones showed significant differences in the absolute content of both parameters indicating an influence of the genotype. Flooding affected the ratio of amino acids to carbohydrates within the reed clones. Plants grown in flooded parts of the fen area revealed a significantly higher total amino acid content together with a lower total content of carbohydrates.Furthermore, the effects of extreme flooding on the content and composition of amino acids and carbohydrates in the basal culm internodes of Phragmites australis were studied in nine reed stands with different degrees of damage on Lake Constance. Shoots from extremely damaged reed stands were characterised by a significant decrease in the total content of carbohydrates, an increase in the total content of amino acids and an increase in the share of γ-aminobutyric acid. These changes in the content and composition of carbohydrates and amino acids were discussed with respect to their value as stress indicators, such as for oxygen deprivation which causes a hypoxic metabolic state in Phragmites australis stands.  相似文献   
618.
剪切对非饱和土土-水特征曲线影响的探讨   总被引:4,自引:1,他引:4  
用净平均应力和吸力等于常数、偏应力增大的三轴排水剪切试验,探讨了剪切对非饱和土水量变化的影响。试验结果表明,土-水特征曲线依赖于偏应力,改进了非饱和土中水量变化的本构关系,建立了含水量.吸力.净平均应力.偏应力形式的土.水特征曲线。  相似文献   
619.
针对流速对D403型苯乙烯系多羟基类弱碱性硼特效离子交换树脂从盐湖卤水中提取硼酸的影响进行了研究,讨论了这种树脂对硼的吸附量与卤水流速的关系。  相似文献   
620.
锌精矿氧压酸浸液中铟的提取研究   总被引:2,自引:0,他引:2  
对锌精矿氧压酸浸液中铟的提取进行了研究,在1.0m o l/L的H2SO4介质中,铟可被P204定量萃取,当萃取相比为O/A=1/4,进行三级萃取,平衡时间为3m in时,In萃取率达97%以上;对负载有机相用3m o l/L的HC l进行三级反萃,O/A=5/1,平衡时间为3m in,In反萃率为99.62%。  相似文献   
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