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91.
长25-29井在完井阶段通井过程中发生粘附卡钻事故,在处理卡钻过程中又发生卡套铣筒、井漏、溢流等事故及复杂情况。通过对井下情况的认真分析,采取先堵漏后循环再解卡的处理方案,顺利地解除了该次卡钻事故,大大地减少了经济损失。 相似文献
92.
进行了PAA(PolyacrylicAcid)-PSF(Polysulfone)交联复合膜的制备,研究了交联剂、添加剂对膜性能的影响,并通过扫描电镜观察了膜的断面结构.研究了PAA-PSF交联复合膜对低浓度有机醇类水溶液反渗透分离性能.发现对于1000×10-6乙醇水溶液截留率达到66.2%,透过流束可达0.9×10-6(m3·m-2·s-1).随醇的分子量的增加,截留率不断上升,对戊醇的截留率达94.3%,而透过流束则保持相对稳定.对不同结构醇类的分离性能研究表明,截留率存在有:tert->sec->iso->n-的规律. 相似文献
93.
混合型表面活性剂液膜法处理含酚废水研究 总被引:25,自引:1,他引:24
研究了兰-113B=Span-80--煤油NaOH液膜体系处理苯酚废水的最佳操作工用于对高浓度含酚废水进行处理,实验结果表明,混合型表面活性剂各项指标均较好,除酚效率可达99%以上,对内相NaOH的最佳浓度的确定给出了估算方法。 相似文献
94.
介绍一种新型聚炔离子导体湿敏材料-聚对二炔苯的Langmuir-Boldgett成膜原理与制备,淀积有10层PDEB LB膜层的声表面波延迟线型湿度传感器的特性。由于LB成膜技术拉制的膜可以在分子水平上进行定量控制,保证了膜的均匀性和一致性。 相似文献
95.
Tadashi Hano Michiaki Matsumoto Takahisa Kawazu Takaaki Ohtake 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1995,62(1):60-63
The extraction equilibria of various di- and tripeptides with di-2-ethylhexylphosphoric acid (D2EHPA) were studied at low pH values. The complex extracted to organic phase consisted of one molecule of peptide and two molecules of D2EHPA dimer. The extraction constants of the peptides correlated well with the distribution coefficients of peptides between 1-octanol and water, which is a measure of hydrophobicity. The permeation rates of peptides through an emulsion liquid membrane were examined by using D2EHPA as a carrier, Span 80 as an emulsifier and kerosene as a diluent. The rates varied considerably with peptide type, depending upon the hydrophobicity. 相似文献
96.
本文对CIMS装配线和拆卸线的可靠性问题进行研究。文中分析了它们的运行状况,求出了两种生产线的稳态可用度,并用一个例子加以说明。 相似文献
97.
本文利用等效工作站理论和工件流平衡原理,推导出非串行离散事件生产线可以等价于串联系统,并归结为装配和拆卸两条定理,解决了系统的建模、分析与设计问题。 相似文献
98.
P Sarkar D Ghosh D Bhattacharya R Kataky SJ Setford SF White APF Turner 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(12):1389-1394
Allergen levels in indoor environments, leading to many diseases, eg asthma, rhinitis and conjunctivitis, affect a large and increasing fraction of the population. A quite effective and inexpensive method of a rough but very rapid overall assessment of total allergen level in the environment has been developed. The method involved estimation of protein in allergen extracts by screen‐printed electrodes using two different techniques. The biosensor comprised a rhodinised carbon working electrode, a silver/silver chloride reference electrode and a carbon counter electrode. In the first method the enzyme protease reacted with allergen protein to release amino acid, which produced hydrogen peroxide in the presence of amino acid oxidase. This was detected amperometrically. The second method used potassium bromide as electrolyte and the electrode was subjected to dual potential. Bromine, released due to electrolysis at higher potential, was consumed by the allergen protein at lower potential. In the first method, a unique technique was used to microencapsulate the enzyme protease and immobilise it on the surface of the electrode by in‐situ polymerisation to avoid contact with the amino acid oxidase. A total of seven allergens were tested and the results gave a good correlation with the standard protein measurement method. Environmental specimens from indoors, schools and workplaces can be evaluated for the aeroallergens produced by dust mites, animal hairs, cockroach debris, pollens, etc as a means of determining the exposure risk. Copyright © 2005 Society of Chemical Industry 相似文献
99.
Selectivity of partial hydrogenation reactions performed in a pore-through-flow catalytic membrane reactor 总被引:2,自引:0,他引:2
The selectivity of partial hydrogenation reactions of unsaturated substrates was studied in a membrane reactor operating at 323 K and 40 bar hydrogen pressure. The reactor system was constructed as a loop of a saturation vessel and a membrane module in which the reaction mixture was resaturated with hydrogen up to 100 times. In a porous membrane made from cross-linked polyacrylic acid palladium nanoparticles were incorporated as catalysts. A well-defined residence time within the membrane was achieved due to a defined pore structure of the membrane and a convective mass flow of the reaction mixture through the membrane. The selectivity for the partially hydrogenated products was investigated as a function of the pore size of the PAA membrane and was compared to commercially available catalysts. Compared to experiments with supported catalysts (Pd/C and Pd/Al2O3) in a slurry and a fixed bed reactor the selectivity for the desired products could be increased by 3% (1-octyne) up to 40% (geraniol). 相似文献
100.
在氯化铵-氨水(pH=11)支持电解质中用微银汞膜电极进行试验,锰、铁不干扰测定,用EDTA滴定氯化钙获得令人满意的结果。对三种样品进行分析,变异系数为0.08%—0.11%。该法快速准确,适用于氯化钙主要成份的测定。 相似文献