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钻柱振动声波录井技术方法及应用实例 总被引:1,自引:0,他引:1
钻柱振动声波录井技术DVL(Drillstring Vibro-acoustic Logging)经过多年的室内研究和现场验证,已经取得了可喜成果,为了进一步完善其解释评价方法,该课题尚需要在现场试用中不断地深化应用研究,近期又一次开展了现场试验。简介了该技术的工作原理、配套硬件构成和无线数据传输系统的特点。结合现场应用实例.阐述了DVL技术发展最新的理论分析方法和研究成果;给出了DVL技术分析中的相关分析法和信号能量计算法;列举了频聚法、能聚法和归一化数据处理方法的理论公式和其应用方法。通过应用实例证实,依据DVL频谱图、频聚和能聚曲线、能量和相位差曲线,能有效地识别地层岩性,划分地层和油藏。同时在钻具工况的分析、辅助识别上能起到了一定的作用,为DVL技术的发展奠定了理论基础。 相似文献
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分析了杂质Al元素在工业硅中的存在形式,并采用加压浸出方法对其进行有效去除。比较了盐酸浓度、反应温度、反应压强、液固比、硅粉颗粒粒度、反应时间等因素对杂质Al脱除效率的影响。实验结果表明,加压浸出过程的较佳反应条件为盐酸浓度4 mol.L-1,反应温度150~160℃,反应压强1.5~1.6 MPa,硅粉最大颗粒尺寸为50μm,液固比:4∶1,反应时间2 h,在此反应条件下,杂质Al的去除效率达到75%,重现性实验研究表明加压浸出处理后的工业硅中杂质Al的残余量小于3×10-4。 相似文献
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We reported on the synthesis and gas-sensor application of copper oxide particles and plates. CuO particles were prepared by a thermal decomposition method, while CuO plates were obtained by a hydrothermal route. The sensitivity of the as-prepared CuO to NO2 gas and alcohol at varied temperatures was studied systematically. The results revealed that the as-synthesized products had high sensitivity and quick response/recovery time at an operating temperature of 200 °C. Furthermore, the CuO plates displayed higher sensitivity to NO2 gas than that of the corresponding particles. This research indicated that CuO plates have potentials in the applications of sensors. 相似文献
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为了掌握野化白云茶树鲜叶加工成黄茶加工过程的影响因素,该研究对比分析了野化白云茶加工的黄茶、烘青绿茶、半烘半炒绿茶的主要品质成分;分析了野化白云茶鲜叶加工黄茶过程中的依工艺阶段取8个茶样(茶青、杀青叶、揉捻叶、再炒叶(除水叶)、闷黄24 h、闷黄48 h、闷黄72 h、毛茶)可培养菌种的变化。野化白云茶与烘青绿茶、半烘半炒绿茶比较,除氨基酸、咖啡碱含量略有下降外,水浸出物含量分别高出4.80%、7.11%,可溶性糖含量分别高出0.41%、0.36%,茶多酚含量、儿茶素总含量呈下降趋势,酯型儿茶素总量下降21.62 mg/g、19.08 mg/g,EGCG下降9.99 mg/g、6.98 mg/g,GCG下降14.23 mg/g、13.80 mg/g,以上成分变化均差异显著(p<0.05);非酯型儿茶素组分中除C减小2.49 mg/g、1.75 mg/g(p<0.05)外,其余非酯型儿茶素组分和总含量变化差异不显(p>0.05);闷黄24 h,酵母菌数量明显,至72 h霉菌成优势菌种(3.5×105 CFU/g);分离鉴出8株微生物,包括1株拟盘多毛孢属,4株青霉属,1株枝孢属及2株酵母菌属,其中Penicillium exsudans菌首次从茶叶加工中和茶叶中分离并鉴定。说明闷黄使茶叶水溶性物质、可溶性糖增加,茶多酚、酯型儿茶素下降,闷黄阶段有微生物繁殖并参与黄茶品质的形成。 相似文献
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Weiyi Sun Pan Li Xue Liu Jiajia Shi Hongming Sun Zhanliang Tao Fujun Li Jun Chen 《Nano Research》2017,10(7):2210-2222
Transition metal dichalcogenide nanodots (NDs) have received considerable interest.We report a facile bottom-up synthetic route for MoS2 NDs by using molybdenum pentachloride and L-cysteine as precursors in oleylamine.The synthesis of NDs with a narrow size distribution ranging from 2.2 to 5.3 nm,was tailored by controlling the reaction time.Because of its coating characteristics,oleyalmine leads to uniformity and monodispersity of the NDs.Moreover,the NDs synthesized have large specific surface areas providing active sites.Graphene possesses outstanding conductivity.Combining the advantages of the two materials,the 0D/2D material exhibits superior electrochemical performance because of the 2D permeable channels for ion adsorption,energy storage,and conversion.The as-prepared MoS2/rGO (~2.2 nm) showed a stable capacity of 220 mAh·g-1 after 10,000 cycles at the current density of 20 A·g-1.Furthermore,a reversible capacity ~140 mAh·g-1 was obtained at a much higher current density of 40 A·g-1.Additionally,this composite exhibited superior catalytic performance evidenced by a small overpotential (222 mV) to afford 10 mA·cm-2,and a small Tafel slope (59.8 mV·decade-1) with good acid-stability.The facile approach may pave the way for the preparation of NDs with these nanostructures for numerous applications. 相似文献
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Carbon-sulfur composites as the cathode of rechargeable Li-S batteries have shown outstanding electrochemical performance for high power devices. Here, we report the promising electrochemical charge-discharge properties of a carbon-sulfur composite, in which sulfur is impregnated in porous hollow carbon spheres (PHCSs) via a melt-diffusion method. Instrumental analysis shows that the PHCSs, which were prepared by a facile template strategy, are characterized by high specific surface area (1520 m2·g?1), large pore volume (2.61 cm3·g?1), broad pore size distribution from micropores to mesopores, and high electronic conductivity (2.22 S·cm?1). The carbon-sulfur composite with a sulfur content of 50.2 wt.% displays an initial discharge capacity of 1450 mA·h·g?1 (which is 86.6% of the theoretical specific capacity) and a reversible discharge capacity of 1357 mA·h·g?1 after 50 cycles at 0.05 C charge-discharge rate. At a higher rate of 0.5C, the capacity stabilized at around 800 mA·h·g?1 after 30 cycles. The results illustrate that the porous carbon-sulfur composites with hierarchically porous structure have potential application as the cathode of Li-S batteries because of their effective improvement of the electronic conductivity, the repression of the volume expansion, and the reduction of the shuttling loss. 相似文献