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1.
陈余万 《大庆石油地质与开发》2003,22(1):44-46
江苏油田的庄 2、韦 2油田属强水敏油田 ,采用热 (水 )洗油井和化学清防蜡效果较差 ,两油田每年因洗井造成地层污染影响的产量损失在 5 0 0 0t以上 ,约占油田产量的 4 5 %。根据集肤效应 ,采用油管电热清蜡技术 ,在含水小于 6 0 %、井斜小于 4 0°的油井上可正常使用 ,一般通电加热 4 0~ 80min后 ,油井井口温度能达到 5 0℃左右 ,最高可达到 6 5℃以上 ,连续加热 5~ 6h即可达到清蜡目的 ,电热清蜡为周期 6 0~ 90d。影响电热清蜡主要指标因素是油井的产液量 ,产液量越小 ,所需要的加热电流和加热电压也越小 ,井口温度达到最高值越低 ,清蜡效果越差。试验的 7口井平均年度投入产出比达到 1∶5 ,经济效益和社会效益十分明显。 相似文献
2.
Nanoscale Hybrid Langmuir-Blodgett Films Based on Cerium-Substituted Heteropolymolybdate and Polyquinoline 总被引:2,自引:0,他引:2
Nanoscale hybrid organic/inorganic Langmuir-Blodgett films of cerium-substituted heteropolymolybdates (CeHPMo) and π-conjugated macromolecule poly(1,2-dihydro-2,2,4-trimethyl) quinoline (PQ) were obtained with auxiliary film-forming material stearic acid(SA) or octadecylamine(ODA). The surface pressure-area isotherms illuminate the formation of the hybrid LB films of PQ/ODA/Ce-HPMo and PQ/SA/Ce-HPMo. The different film-forming mechanism was discussed when the different auxiliary film-forming materials were used in the system. The absorption spectra indicate that the molecules of PQ and Ce-HPMo are incorporated into the LB films. Tapping-mode AFM image reveals a granular surface texture of nanosized Ce-substituted heteropolymolybdate. STM image shows that the conductivity is greatly improved after Ce-substituted heteropolymolybdates are incorporated in the films. 相似文献
3.
朱珉 《电气电子教学学报》2002,24(6):55-56
本文介绍由东南大学组织编写,东南大学出版社出版的《电工电子实践课程丛书》的编写背景,每本教材内容的简要内容,特色与使用情况。 相似文献
4.
This article reports the effect of three cobalt carboxylates—cobalt stearate (CoSt3), cobalt palmitate (CoPal3), and cobalt laurate (CoLau3)—on the thermo‐oxidative degradation of low‐density polyethylene (LDPE) films prepared by sheeting process. The carboxylates were blended with LDPE in the concentration range of 0.05–0.2% (w/w). The degradation was monitored by techniques such as FTIR spectroscopy, change in the mechanical properties (tensile strength and elongation at break), viscometry, surface electron microscopy, melt flow index measurements, and apparent density measurements. Studies indicate that films containing these additives are highly susceptible to thermo‐oxidative degradation. Oxygen containing functionalities such as carbonyl and vinyl species are generated on the surface of polyethylene because of thermo‐oxidation, as indicated by FTIR studies. This oxidative process is accelerated in the presence of cobalt carboxylates. The degradation of LDPE was found to increase proportionally with concentration as well as with increasing chain length of the cobalt carboxylate, and follow the order CoSt3 > CoPal3 > CoLau3. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3758–3765, 2007 相似文献
5.
珍珠粉、珍珠层粉、珍珠母粉的热重及热重动力学 总被引:1,自引:0,他引:1
采用热重及热重动力学方法 ,分别研究珍珠粉、珍珠层粉和珍珠母粉的热分解过程及其反应机理。结果表明 ,珍珠粉和珍珠层粉的热分解可分为二个阶段 :第一阶段为 2 50~ 370℃之间 ,失重率约 3% ,反应级数为 1 .6,活化能为 1 0 5~ 1 1 0 k J/ mol属于有机质的热分解 ;第二阶段为 60 0~ 770℃ ,失重率约为 40 % ,反应级数为 1 .3,活化能为 2 80~ 2 90 k J/ mol,属于碳酸钙的分解。珍珠母粉在 2 50~ 370℃之间不存在明显的失重。根据这一现象 ,可以通过热重分析来鉴别珍珠及其制品。 相似文献
6.
热化学反应法镁合金陶瓷涂层的制备及性能的影响 总被引:4,自引:0,他引:4
采用热化学反应法在镁合金基体上制备陶瓷涂层,并对涂层进行耐磨、耐蚀等性能分析.通过XRD物相分析,涂层中有新相生成.且涂层相对基体耐磨、耐蚀性能均有所提高. 相似文献
7.
8.
以无创检测人体血糖为应用需求,采用高灵敏度锇氧化还原聚合物修饰在薄膜电极上,并通过戊二醛交联法固定酶分子制备成新型生物传感器。实验结果表明:在0~700μmol/L的葡萄糖标准浓度范围内,传感器灵敏度为23.955 nA/(μmol.L-1),最低检测限为0.3μmol/L,相关系数为0.999;在标准皮下葡萄糖浓度0~19mmol/L浓度范围内,被抽取出的葡萄糖电流响应值与皮下葡萄糖的浓度成线性关系,线性相关系数为0.994,灵敏度为4.03 nA/(mmol.L-1);单只传感器对100μmol/L葡萄糖检测的精度为4.07%(n=10),不同传感器之间对100μmol/L葡萄糖测量的精度为3.22%(n=10),在4℃条件下,传感器的寿命可达450 d。 相似文献
9.
Pimpisut Worakajit Pinit Kidkhunthod Thanasee Thanasarnsurapong Saran Waiprasoet Hideki Nakajima Taweesak Sudyoadsuk Vinich Promarak Adisak Boonchun Pichaya Pattanasattayavong 《Advanced functional materials》2023,33(25):2209504
Solution-processed copper(I) thiocyanate (CuSCN) typically exhibits low crystallinity with short-range order; the defects result in a high density of trap states that limit the device's performance. Despite the extensive electronic applications of CuSCN, its defect properties are not understood in detail. Through X-ray absorption spectroscopy, pristine CuSCN prepared from the standard diethyl sulfide-based recipe is found to contain under-coordinated Cu atoms, pointing to the presence of SCN− vacancies. A defect passivation strategy is introduced by adding solid I2 to the processing solution. At small concentrations, the iodine is found to exist as I− which can substitute for the missing SCN− ligand, effectively healing the defective sites and restoring the coordination around Cu. Computational study results also verify this point. Applying I2-doped CuSCN as a p-channel in thin-film transistors shows that the hole mobility increases by more than five times at the optimal doping concentration of 0.5 mol.%. Importantly, the on/off current ratio and the subthreshold characteristics also improve as the I2 doping method leads to the defect-healing effect while avoiding the creation of detrimental impurity states. An analysis of the capacitance-voltage characteristics corroborates that the trap state density is reduced upon I2 addition. 相似文献
10.
Yannick Schellander Marius Winter Maurice Schamber Fabian Munkes Patrick Schalberger Harald Kuebler Tilman Pfau Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(5):363-372
In this work, real-time ultraviolet photodetectors are realized through metal–semiconductor–metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) is used as semiconductor material and gold as metal electrodes. The readout of an individual sensor is implemented by a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. The photosensor and the transimpedance amplifier are both manufactured on glass substrates. The measured photosensor possesses a high responsivity R , a low response time t R E S , and a good noise equivalent power value NEP . 相似文献