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61.
向兴金 《油田化学》1992,9(4):370-375
聚合物抑制剂是聚合物泥浆的重要组成部分。本文报导了聚合物抑制剂的发展动向,介绍了作为聚合物泥浆抑制剂的阳离子型聚合物、复合离子型聚合物、非离子型聚合物及改性的部分水解聚丙烯酰胺。  相似文献   
62.
含H_2S井完井液对井下金属管串具有腐蚀性。采用锌基或铁基螯合物除硫剂及咪唑啉缓蚀剂可有效地防止这种腐蚀的发生。本文对H_2S的腐蚀、除硫剂和缓蚀剂产品及其对产层的损害作了介绍与探讨。  相似文献   
63.
钢蜗轮摩擦副边界润滑状态判断及润滑油添加剂选择   总被引:3,自引:0,他引:3  
使用Johnson和Hooke编制的润滑状态区域图,对实验所用的中心距为120mm钢蜗轮减速器摩擦副的润滑状态进行了计算与判断,根据润滑类型,合理选择了润滑油添加剂。  相似文献   
64.
碱木素油田化学剂研究进展   总被引:5,自引:0,他引:5  
谌凡更  李忠正 《油田化学》1996,13(2):183-188
本文综述了碱木素类油田化学剂的研究进展。以碱木素为主要原料,可以制成许多油田化学剂,如钻井液添加剂、油井水泥添加剂、堵水调剖剂、表面活性剂采油的牺牲剂、原油乳化降粘剂等。利用碱木素制备油田化学剂可降低油田化学剂的成本,减少纸厂制浆黑液对环境的污染,有发展前景。  相似文献   
65.
顾军  王学良 《油田化学》1996,13(3):269-272
本文综述了国内钻井液转化成水泥浆技术(MTC技术)研究和应用简况并作了分析讨论。  相似文献   
66.
An internet website (http://cpf.jrc.it/smt/) has been produced as a means of dissemination of methods of analysis and supporting spectroscopic information on monomers and additives used for food contact materials (principally packaging). The site which is aimed primarily at assisting food control laboratories in the European Union contains analytical information on monomers, starting substances and additives used in the manufacture of plastics materials. A searchable index is provided giving PM and CAS numbers for each of 255 substances. For each substance a data sheet gives regulatory information, chemical structures, physico-chemical information and background information on the use of the substance in particular plastics, and the food packaging applications. For monomers and starting substances (155 compounds) the infra-red and mass spectra are provided, and for additives (100 compounds); additionally proton NMR are available for about 50% of the entries. Where analytical methods have been developed for determining these substances as residual amounts in plastics or as trace amounts in food simulants these methods are also on the website. All information is provided in portable document file (PDF) format which means that high quality copies can be readily printed, using freely available Adobe Acrobat Reader software. The website will in future be maintained and up-dated by the European Commission's Joint Research Centre (JRC) as new substances are authorized for use by the European Commission (DG-ENTR formerly DGIII). Where analytical laboratories (food control or other) require reference substances these can be obtained free-ofcharge from a reference collection housed at the JRC and maintained in conjunction with this website compendium.  相似文献   
67.
Pre-rigor filleting as well as brining with a mixture of phosphates and salt could influence several quality parameters of cod fillets. The aim of this work was to evaluate which of these processes that affected selected quality parameters of farmed cod the most. The analyses were performed at several points during storage, enabling that the effects of time of filleting, brining and storage could be evaluated simultaneously.Pre- and post-rigor non-brined fillets had similar and significant weight loss during storage. The weight increase of pre- and post-rigor fillets due to brining were 2% and almost 10%, respectively, and brining significantly reduced the weight loss during storage. Liquid loss and total viable count (TVC) were significantly influenced by rigor state at time of filleting, brining and storage time, while water content was influenced significantly by time of filleting and brining. Brining and storage time significantly influenced the whiteness, while time of filleting and storage time had significant influence upon the fillet index. The growth of Photobacterium phosphoreum was affected by storage time only, and the pH of the fillets was not influenced significantly by any of the parameters tested.  相似文献   
68.
Silica fume is used as an admixture to concrete to improve the engineering properties. Additions of silica fume improve the bond between concrete and steel reinforcing bars. The authors describe a laboratory study which explores the ultimate pullout load of steel reinforcing bars from concrete enhanced with silica fume. Les fumees de silice utilisees comme adjuvant ameliorent les proprietes techniques du beton et notamment l'adherence entre le beton et les fers d'armature. Les auteurs decrivent une etude de laboratoire qui porte sur la resistance a l'arrachement des fers d'armature dans du beton traite aux fumees de silice.  相似文献   
69.
Thermal reactions between cathode particles (LiNi0.8Co0.2O2, LiCoO2, LiMn2O4 and LiFePO4) and ternary electrolyte (1.0 M LiPF6 in 1:1:1 diethyl carbonate/dimethyl carbonate/ethylene carbonate) with or without the thermal stabilizing additive dimethyl acetamide (DMAc) have been investigated. Ternary electrolyte reacts with the surface of lithiated metal oxides (LiNi0.8Co0.2O2, LiCoO2 and LiMn2O4) upon storage to corrode the surface and generate a complex mixture of organic and inorganic surface species, but the bulk ternary electrolyte does not decompose. There is little evidence for reaction between the surface of carbon coated LiFePO4 and ternary electrolyte upon storage at elevated temperature (>60 °C), but the bulk ternary electrolyte decomposes. Addition of DMAc to ternary electrolyte reduces the surface corrosion of the lithiated metal oxides and stabilizes the electrolyte in the presence of LiFePO4.  相似文献   
70.
Physicochemical properties and quality of Pacific white shrimp (Litopenaeus vannamei) treated with alkaline soaking solution (ASS; 0.75% NaOH with 2.5% NaCl) containing 3% monosodium glutamate (MSG), pH 11.5 (ASS+3% MSG) were investigated, in comparison with those treated with mixed phosphates or ASS alone. Muscle proteins underwent conformational changes as evidenced by the shift of Tmax to the lower temperature and the increased negative charge when treated with ASS+3% MSG. This coincided with the higher moisture and NaCl contents (P < 0.05). Such a treatment led to the pronounced swelling of muscle fibrils as visualised by scanning electron microscope. Highest likeness score for all attributes except for flavour was observed in sample treated with ASS+3% MSG. Slightly fishy odour in the treated sample was associated with higher abundance of volatile compounds, especially alcohol and aldehyde. Thus, ASS+3% MSG could be used as the replacer of phosphate and bicarbonate for shrimp processing.  相似文献   
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