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压裂改造是低渗透油藏油井增产和提高原油采收率的重要措施。压裂效果的好坏与压裂液的性能息息相关,目前国内常用的田菁胶与改性田菁胶压裂液残渣含量较高,对地层伤害较大。本文提出一种优于田菁胶类的新型压裂液——SC-1型植物胶压裂液,它具有耐温性能好、携砂能力强、滤失低、破胶化水彻底、残渣含量低、对地层伤害小等特点,适合于地层温度为80℃~140℃的油层进行压裂改造,该压裂液已在现场应用一百余井次,取得了较好的经济效益。 相似文献
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G02/G03在数控编程中的快速判定 总被引:2,自引:0,他引:2
在数控手工编程学习中,对圆弧编程中顺时针G02插补与逆时针G03插补,常常理解错误,导致所编程序与实际加工路线相反.根据数控编程标准,圆弧插补指令描述如下: 相似文献
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1 INTRODUCTIONSn-doped In2O3(ITO) is one kind of n-typesemiconductor material[1].It has excellent electro-optical properties , such as electrical conductivityand high transparency under visible light[2],andiswidely used in electronic , transparent electrode ,solar cells and electro-irradiance , especially inscreen display[3 ,4].Recently nearly half of the met-al indium has been used to prepare ITO materialsin the developed countries[5], such as Japan, A-merica ,France and so on.So the… 相似文献
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Synthesis of mesoporous cerium-zirconium mixed oxides by hydrothermal templating method 总被引:1,自引:0,他引:1
Mesoporous cerium-zirconium mixed oxides were prepared by hydrothermal method using cetyl trimethyl ammonium bromide (CTAB) as template. The effects of amount of template, pH value of solution and hydrothermal temperature on mesostructure of samples were systematically investigated. The final products were characterized by XRD, TEM, FT-IR, and BET. The results indicate that all the cerium-zirconium mixed oxides present a meso-structure. At molar ratio of n(CTAB)/n((Ce)+(Zr))= 0.15, pH value of 9, and hydrothermal temperature of 120 ℃, the samples obtained possess a specific surface area of 207.9 m^2/g with pore diameter of 3.70 nm and pore volume of 0.19 cm^3/g. 相似文献
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Sn-doped In2O3 (ITO) nanopowders were prepared in ethanol solvent by solvothermal process. The effects of the solvothermal temperature, coprecipitation pH value and SnO2 content on the products phase and microwave absorption were investigated by X-ray diffractometry and microwave reflectance. ITO nanopowders with cubic structure can be respectively prepared at 250 and 270 ℃ for 6 h. The prepared product is InOOH or the mixture of InOOH and In3Sn4O12 when the solvothermal temperature is below 250℃. With rising solvothermal temperature and prolonging time, the absorption of the ITO powders gradually decreases. The products are ITO nanopowders by coprecipitating at pH=9 or 11, but ITO powders with Sn3O4 at pH=6. The absorption of powders prepared at pH=6 is better than that at any other pH value. The products are all ITO nanopowders and crystal size reduces with increasing SnO2 content. The microwave absorption of ITO nanopowders with SnO2 content of 8% (mass fraction) is the best among samples with different SnO2 contents. 相似文献