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1.
《云南化工》2018,(12):93-94
石油和天然气的储存和运输,即石油和天然气资源的储存和运输,是有效利用石油和天然气资源的重要先决条件。随着中国经济社会的快速发展和油气储运技术的更新和发展,油气储运业面临着重大机遇和挑战。针对油气储运技术发展现状,确定基于安全,环保,节能的油气储运技术要不断的创新,才能促进油气进一步发展。  相似文献   

2.
油气是重要的战略资源,关系国计民生。随着工业化和城镇化的加速推进以及汽车进入普及期,我国油气供需形势日趋严峻。解决我国油气供应不足的问题。应首先立足于开发利用国内的油气资源,不断提高自给水平,然而却存在管理体制和政策的掣肘。世界油气主产国都不断改善其油气资源开发利用的管理体制与政策,促进更加有效与合理地开发利用和保护油气资源。本文总结了该领域的国际经验,从加强油气资源法律法规体系建设、促进油气资源管理体制改革、完善油气资源矿业管理等方面提出了对我国的启示和改革建议。  相似文献   

3.
Isomerization of isopropylidene glycerol ketals and benzylidene glycerol acetals was studied, and isoraerization equilibria were established. Reaction of benzaldehyde with glycerol gave four benzylidene glycerol isomers, which were separated by column chromatography and characterized by NMR spectroscopy and other methods. Isomerization of 1- and 2-monoglycerides and of 1,2- and 1,3-diglycerides, and their separation by column chromatography, are described. Mechanisms of isomerization in mono- and diglycerides and factors which affect them are discussed. Isomerization of 1- and 2-glycerophosphates and of cyclic glycerophosphates by acid and base was also studied. Hydrolysis products of L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine were separated by column chromatography and characterized by periodic acid oxidation, optical rotation, and NMR spectroscopy. No isomerization of unhydrolyzed L-3-glycerylphosphorylcholine and 2-glycerylphosphorylcholine was observed. Evidence indicated that acid-catalyzed hydrolyses of phosphoglycerides are under thermodynamic control whereas most base-catalyzed hydrolyses are under kinetic control.  相似文献   

4.
感光科学与光化学   总被引:1,自引:0,他引:1  
《感光科学与光化学》2005,23(5):F0004-F0004
本刊主要刊登感光科学和光化学领域的研究成果,同时刊登有关信息科学及信息材料,包括信息储存稀己录、信息的处理和加工及信息显示材料等;光/电化学及光电子技术,包括光/电转换及储存材料、电光材料、非线性光学材料、纳米材料、电致发光材料及器件研究以及化学和物理发光等领域;光生物,光医学及生命科学与环境科学中的有关问题的新理论、新概念、新技术和新方法,以促进国内外的学术交流。  相似文献   

5.
论述了近年来全球食用油和非食用油的产量和消耗量以及2020年全球油脂的需求及产量预测。指出全球油脂产量受各种条件影响和限制,存在许多可变因素,并对全球油脂价格的波动进行了分析。  相似文献   

6.
分析了火炸药与武器信息化的关联性;论述了火炸药在武器装备发展中的综合地位与作用;提出作为武器信息化条件下火炸药发展策略和基本点的六项技术,即火炸药相关信息量的整合与准确表达、高能量与高安全性的统一、能量释放的可控制性、洁净燃烧与爆炸技术、燃烧爆炸的物理与化学作用延伸、非致命武器与化学战剂等.  相似文献   

7.
以山核桃、油茶和板栗3类果蓬为原料,研究了此类原料与杉木、松木屑在不同配比条件下对果蓬类致密成型特征及其机制炭质量的影响。证实了果蓬类原料因纤维素含量、木质素含量与杉木、松木存在差异,且因较高的灰分含量限制,需与杉木或松木屑等原料在一定配比条件下才可实现良好的致密成型。而配比选择试验结果则表明,果蓬原料与杉木、松木屑混合原料以3:7比例配料为宜;在此条件下,制备的机制炭外形平直无裂缝,得率为 33.85%~36.73%,固定碳含量 79.80%~86.20%,热值28.96~31.92 MJ/kg。  相似文献   

8.
临兴地区位于鄂尔多斯盆地东缘河东煤田中部,前期勘探和试井生产显示该区块具有良好的煤层气、页岩气和致密砂岩气资源前景。通过对3种非常规天然气资源勘探和开发地质条件的系统分析,结果表明,临兴地区具有煤层气、页岩气和致密砂岩气优越的成藏条件和良好的配置关系,煤层—页岩—致密砂岩3种储层中天然气连续聚集成藏,受物质基础和保存条件的影响,不同的层位和构造位置上存在差异。提出了该地区非常规天然气的勘探开发可遵循以下原则:东部浅层进行太原组煤层气、页岩气以及山西组煤层气的合探共采,西部深层集中进行山西组页岩气、致密砂岩气以及太原组致密砂岩气的合探共采。从而为该地区非常规天然气的利用提供科学依据。  相似文献   

9.
Carbon aerogels were prepared by sol-gel polymerization of phenolic novolak and furfural followed by supercritical drying and pyrolysis. The porosity and morphologies of carbon aerogels were characterized by nitrogen adsorption, apparent density, He- pycnometer method, and transmission electronic microscopy (TEM). Effect of ratios of phenolic novolak to furfural (Ra) and total concentration of reactants (C) in sol-gel step on porosity and morphologies of carbon aerogels was investigated. The carbon aerogels synthesized are rich in meso- and macropores. The Ra determines the cross-linking density of polymers, thereby the compatibility of the polymers, and ultimately the shrinkage of gels in the drying and pyrolysis. The network sizes and the porosity of organic and carbon aerogels are mainly determined by Ra. The C has no effect on volume shrinkage of gels in drying and pyrolysis and has only dilute effect in determining bulk density of organic and carbon aerogels, and ultimately the porosity of carbon aerogels. Conversion of mesopores to micro- and macropores is observed, which is related to combination of C and Ra, and determines the partition of micro-, meso- and macropores.  相似文献   

10.
Cycloaliphatic C21 di- and C22 tricarboxylic acids were prepared by the Diels-Alder reaction of dehydrated castor oil (DCO) fatty acids (containing 48% conjugated and 42% nonconjugated dienes) with acrylic and fumaric acids, respectively. The reaction temperature, time, catalyst concentration, and mole ratio of reactants were varied to get maximum yields of the di- and tricarboxylic acids. The unreacted DCO fatty acids were removed from the products by partition between aqueous methanol and n-hexane. The products were converted to methyl esters and characterized as the substituted cyclohexene derivatives before and after dehydrogenation with Pd/C in xylene, hydrogenation with Pd/C in decalin and oxidation with periodate-permanganate reagent and by mass and proton nuclear magnetic resonance spectrometry. The acids were converted to sodium soaps, mono- and diethanolamides and the corresponding diol and triol sulfates, and the resulting products were evaluated for their surface-active properties. The sodium soaps showed better calcium tolerance and poorer foaming power than sodium oleate. The diethanolamides were inferior to lauroyl diethanolamide in wetting and emulsifying power. The monoethanolamides were better than the respective diethanolamides and lauroyl diethanolamide in wetting property. The diol and triol sulfates were poorer in wetting and emulsifying ability and better in calcium tolerance than sodium lauryl sulfate.  相似文献   

11.
萜类化学品中试设备的中央数字化监控系统的研究与设计   总被引:1,自引:1,他引:0  
在认真分析了萜类化学品中试工艺现状及特征的基础上,提出了该类工艺和设备进行中央监控系统集成及数字化技术改造的DCS技术应用及实施方案。研究开发了具有友好人机操作界面、可组态实时控制功能、集成工艺参数检测和控制手段、人性化报表输出和记录功能的中央数字化监控系统(CDMCS)。由设备、工艺和 CDMCS 集成的萜类化学品中试装置已得到实际应用,经过 90 多天成功试运行,表明该系统测控准确,运行稳定,操作便捷,工艺技术试验数据达到了设计要求。  相似文献   

12.
Skeletal structure and body composition may be altered permanently in response to aggressions during critical periods of growth. This increases propensity to adverse effects in adulthood. The study explored the association of anthropometric variables of body size and proportions and of body composition with systolic (SBP) and diastolic (DBP) blood pressure (BP) in young adults. We studied 166 men and 246 women age 20-34. SBP, DBP, weight, stature, sitting height, circumferences (waist, hip), breadths (biacromial, biiliac) and skinfolds (bicipital, tricipital, subscapular, suprailiac) were assessed. BMI, waist-hip ratio (WHR), waist-stature ratio, and Sigma skinfolds-stature were calculated. Pearson correlations were determined for anthropometric variables with SBP and DBP and linear regression models for SBP and DBP were developed by sex. Correlation coefficients between indicators and BP were significant, except for stature and SBP and DPB, and WHR with DBP in women; and stature with DBP, biiliac breadth and WHR with SBP, and sitting height with SBP and DPB in men. SBP and DPB were explained by weight, BMI, and biiliac breadth in multivariable analysis in women, where 15.4% and 10.8% of variance of SBP and DPB was explained. In men, SBP was explained by weight, Sigma skinfolds and WHR, and DBP by Sigma skinfolds; models explained almost 20% of SBP and DPB variance. No association was found between BP and past malnutrition indicators. Biiliac breadth, weight and BMI in women, and weight, WHR and Sigma skinfolds in men explained BP. The use of biiliac breadth in the assessment of hypertension risk in women should be explored further.  相似文献   

13.
高等院校和科研机构等在实施科技产业化或技术转化过程中,工程公司的桥梁作用不可或缺,应得到从事科技产业化或技术转化管理部门的认同和重视。  相似文献   

14.
烯烃催化氧化反应的研究进展   总被引:1,自引:0,他引:1  
刘晓红  由宏君 《当代化工》2004,33(3):146-149
介绍了烯烃催化氧化的发展现状,论述了烯烃催化氧化的具体方法,其中包括烯烃气固相催化环氧化反应、烯烃液相催化环氧化反应、模拟酶催化烯烃环氧化反应、以次氯酸钠和过氧化氢为氧源的烯烃环氧化反应和光催化烯烃直接环氧化反应。以H2O2为氧化剂,烯烃进行环氧化反应时,不污染环境,并且有利于环境保护。  相似文献   

15.
The important factors to be considered in the provision, storage and handling of dyes and chemicals are discussed and related to their contribution to the efficient use of production resources in modern dyeing and finishing plants. The conditions necessary for optimum storage of materials in the dye-store are outlined and the advantages and limitations of bulk storage systems and methods of stock control are briefly summarized. Dispensing methods for dyes and chemicals in the colour kitchen are briefly reviewed in the light of recent developments and related to improvements in process and quality control. In addition, some general views on health and safety and on the selection and training of operatives for colour kitchens are presented.  相似文献   

16.
《Ceramics International》2023,49(8):12201-12213
Tetracycline (TC) and oxytetracycline (OTC) are antibiotic compounds increasingly detected in various water sources. In this study, Fe-metal organic framework incorporated biopolymer-clay hydrogels (CAMIL-MMT and CAMIL-SEP) were prepared to remove TC and OTC from water. The physicochemical properties of the as-prepared hydrogels were thoroughly characterized, and the effect of various operating parameters on the adsorption performance was systematically examined. The CAMIL-MMT hydrogel showed the maximum adsorption capacity for TC and OTC (24.59 and 26.14 mg/g, respectively) compared to the CAMIL-SEP and other forms of biopolymer hydrogel precursors. The effects of the contact time and initial concentration on TC and OTC adsorption by CAMIL-MMT and CAMIL-SEP hydrogels were well suited to the pseudo-second-order kinetics and Freundlich isotherm models. The adsorption performance of CAMIL-MMT and CAMIL-SEP hydrogels slightly decreased with an increase in solution pH, while it was not much influenced by the co-existing anions. The thermodynamic study indicated that the reactions for the uptake of TC and OTC were spontaneous and highly favorable. Moreover, the as-synthesized CAMIL-MMT and CAMIL-SEP hydrogels demonstrated strong potential for reuse in TC and OTC removal with high reusability and strong stability. The photocatalysis study revealed that residual TC and OTC after adsorption could be further degraded by CAMIL-MMT and CAMIL-SEP hydrogels under visible light irradiation. From the above-mentioned results, the as-synthesized CAMIL-MMT and CAMIL-SEP hydrogels are promising to be considered alternative materials for the adsorptive and photocatalytic removal of TC and OTC in practical application of water and wastewater treatment.  相似文献   

17.
综述了2013年国内外高活性聚异丁烯现有的装置能力和实际开工情况,对国内外高活性聚异丁烯的生产工艺和成本情况进行了对比。介绍了国内外高活性聚异丁烯主要应用领域及应用现状。介绍了近几年国内外高活性聚异丁烯市场需求变化和价格情况,分析了国内高活性聚异丁烯市场与国际市场的关联。介绍了国内高活性聚异丁烯技术现状及研发方向,对国内高活性聚异丁烯今后应用领域及市场发展趋势进行了分析和预测。  相似文献   

18.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

19.
丁训慎 《清洗世界》2006,22(5):27-32
核电站在运行时,腐蚀产物和杂质会从二回路迁移到蒸汽发生器中,这些物质中有很大一部分将残留在蒸汽发生器内,成为泥渣和污垢,并逐渐在管板和支撑板上部、管子表面、支撑板与管子的缝隙内沉积。如果这些泥渣与污垢未被清除,将越积越厚,越来越硬,不易渗透,会使蒸汽发生器降质并影响其性能。文章介绍了泥渣与污垢的形成及其危害,泥渣与污垢中的物理化学过程、管板与管束的清洗方法、泥渣与污垢的数量及其清洗。  相似文献   

20.
The pot experiment conducted in calcareous soil of Saurashtra, India showed that application of lime (20% CaCO3) and excess water (irrigation at –0.3 bar) to the soil enhanced chlorosis in groundnut leaves caused by induced deficiencies of iron, sulphur and zinc, which was recovered by applying agricultural grade chemicals containing iron, sulphur and zinc. This chlorosis caused 29.8 and 19.1% reduction in pod yield of groundnut due to lime and excess water, respectively in the untreated control pot and 17.1 and 9.6%, respectively in the pot treated with different chemicals.Application of iron sulphate, zinc sulphate, iron pyrite, gypsum, phospho-gypsum, elemental sulphur, wettable sulphur and Fe-EDTA decreased chlorosis and increased chlorophyll and carotenoid contents of leaves, uptake of Fe, S and Zn and pod yield of groundnut significantly. The foliar spray of 0.5% aqueous solution of iron sulphate, zinc sulphate and Fe-EDTA at 20, 35, 50 and 65 days after emergence (DAE) was more effective than their soil applications. The Fe-EDTA corrected only iron chlorosis, and gypsum, phosphogypsum and elemental sulphur only sulphur chlorosis. However, iron sulphate and iron pyrite corrected iron and sulphur and zinc sulphate corrected zinc and sulphur chlorosis. Among the soil amendments, application of iron sulphate and iron pyrite showed better responses to groundnut and showed higher Fe and S uptake than other treatments. The responses of gypsum, phosphogypsum and elemental sulphur were at par. The correlation study showed that pod yield of groundnut was negatively correlated with chlorosis and positively correlated with the chlorophyll and carotenoid contents in groundnut leaves.  相似文献   

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