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Experimental Investigation of Second Interface Cement Bond Evaluation

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Petroleum Science 2007年第2期4卷 39-43页

作者： Che Xiaohua qiao wenxiao School of Resources and Information China University of Petroleum Beijing 102249 China

Cement bond model wells （1：10 scaled-down） were made with a gradually degrading cement annulus for cement bond evaluation of the first interface （between the casing and the cement annulus） and the second interface （between the cement annulus and the formation）. Experimental simulation on cement bond logging was carried out with these model wells. The correlation of acoustic waveforms, casing wave energy and flee casing area before and after cement bonding of the second interface was established. The experimental results showed that the arrival of the casing waves had no relationship with the cement bonding of the second interface, but the amplitude of the casing head wave decreased obviously after the second interface was bonded. So, cement bonding of the second interface had little effect on the evaluation of the cement bond quality of the first interface by using casing head wave arrivals. Strong cement annulus waves with early arrivals were observed before the second interface was bonded, while obvious ＂formation waves＂ instead of cement annulus waves were observed after the second interface was bonded.

关键词： Cement bonding quality second interface cement annulus wave casing wave

Numerical simulation of an acoustic field generated by a phased arc array in a fluid-filled borehole

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Petroleum Science 2009年第3期6卷 225-229页

作者： Che Xiaohua qiao wenxiao State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

The acoustic tools widely used in borehole well logging and being developed in borehole acoustic reflection imaging do not have the function of azimuthal measurement due to a symmetric source, so they can not be used to evaluate the azimuthal character of borehole formation. In this paper, a 3D finite difference method was used to simulate the acoustic fields in a fluid-filled borehole generated by a traditional monopole source and a phased arc array. Acoustic waveforms were presented for both cases. The analysis of the simulated waveforms showed that different from the monopole source, the acoustic energy generated by the phased arc array transmitter mainly radiated to the borehole in a narrow azimuthal range, which was the key technique to implement azimuthal acoustic well logging. Similar to the monopole source, the waveforms generated by the phased arc array in the fluid-filled borehole also contain compressional （P） waves and shear （S） waves refracted along the borehole, which is the theoretical foundation of phased arc array acoustic well logging.

关键词： Phased arc array acoustic field acoustic well logging azimuth finite difference method

Numerical simulation of an acoustic field generated by a phased arc array in a fluid-filled cased borehole

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Petroleum Science 2014年第3期11卷 385-390页

作者： Che Xiaohua qiao wenxiao Wang Ruijia Zhao Yuhong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Key Laboratory of Earth Prospecting and Information Technology China University of Petroleum China National Oil & Gas Exploration & Development Company

Transducers that are widely applied in cement bond evaluation tools, such as cement bond logs and variable density logs, cannot radiate acoustic energy directionally because of the characteristics of monopole sources. A phased arc array transmitter, which is a novel transducer that differs from monopole and dipole transducers, is presented in this study. To simulate the acoustic field generated by a phased arc array in a fluid-filled cased borehole with different channelings, a 3D finite-difference time-domain method is adopted. The acoustic field generated by a traditional monopole source is also simulated and compared with the field generated by the phased arc array transmitter. Numerical simulation results show that the phased arc array radiates energy directionally in a narrow angular range in the borehole, thereby compressing the acoustic energy into a narrow range in the casing pipe, the cement, and the formation. We present the analyses of first-arrival waveforms and the amplitudes of casing waves at different azimuthal angles for the two different sources. The results indicate that employing a directional source facilitates azimuthal identification and analysis of possible channeling behind the casing pipe.

关键词： Phased arc array azimuthal angle first-arrival amplitude acoustic field cased borehole

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益气除瘟方治疗气虚感冒的临床观察

中国民间疗法 2024年第9期32卷 72-74页

作者：李典薛晓明孟丽红张晔乔文晓山西中医药大学山西太原030024 山西省中医院山西太原030012

目的:观察益气除瘟方治疗气虚感冒的临床疗效。方法:将60例气虚感冒患者随机分为对照组和观察组,每组30例。对照组采用玉屏风胶囊治疗,观察组采用益气除瘟方治疗。治疗5d后,比较两组患者的临床疗效、不良反应发生情况,以及治疗前后的中... 详细信息

目的:观察益气除瘟方治疗气虚感冒的临床疗效。方法:将60例气虚感冒患者随机分为对照组和观察组,每组30例。对照组采用玉屏风胶囊治疗,观察组采用益气除瘟方治疗。治疗5d后,比较两组患者的临床疗效、不良反应发生情况,以及治疗前后的中医证候积分。结果:治疗后,两组患者中医证候积分均低于治疗前,且观察组低于对照组,差异均有统计学意义(P<0.05)。观察组总有效率为90.00%(27/30),高于对照组的66.67%(20/30),差异具有统计学意义(P<0.05)。两组患者在治疗期间均未发生严重不良反应。结论:益气除瘟方治疗气虚感冒可获得显著疗效,安全性较高。

关键词：气虚感冒益气除瘟方玉屏风胶囊

Effects of boundary conditions on vibrating mode of acoustic logging dipole transducer

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Science China Earth Sciences 2008年第S2期51卷 195-200页

作者： qiao wenxiao,CHE XiaoHua & ZHANG Fei State Key Laboratory of Petroleum Resource and Prospecting,China University of Petroleum,Beijing 102249,China 1. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China

Acoustic transducer is an important part of acoustic well logging tool. In this paper,ANSYS software package is used to design acoustic dipole transducer and simulate vibrating mode of the dipole transducer in different mechanical boundary conditions. The results show that boundary conditions influence the number of vibrating mode in the same frequency band and the frequency value of the same vibrating mode. Several acoustic dipole transducers are designed according to the results of numerical simulation and laboratory measurements. The basic frequency of vibrating mode of experi-ment has good agreement with that of simulation. The numerical simulation plays a good guidance role in designing,producing and correctly installing the acoustic dipole transducer.

关键词： acoustic dipole transducer vibrating mode basic frequency acoustic well logging

First-principles study on the heterogeneous formation of environmentally persistent free radicals(EPFRs)overα-Fe2O3(0001)surface:Effect of oxygen vacancy

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Journal of Environmental Sciences 2024年第8期142卷 279-289页

作者： wenxiao Pan Shuming He qiao Xue Xian Liu Jianjie Fu Kang Xiao Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310012China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China

Metal oxides with oxygen vacancies have a significant impact on catalytic activity for the transformation of organic pollutants in waste-to-energy(WtE)incineration *** study aims to investigate the influence of hematite surface oxygen point defects on the formation of environmentally persistent free radicals(EPFRs)from phenolic compounds based on the first-principles *** oxygen-deficient conditions were considered:oxygen vacancies at the top surface and on the *** simulations indicate that the adsorption strength of phenol on theα-Fe_(2)O_(3)(0001)surface is enhanced by the presence of oxygen ***,the presence of oxygen vacancies has a negative impact on the dissociation of the phenol molecule,particularly for the surface with a defective point at the top ***-kinetic parameters were established over a temperature range of300-1000 K,and lower reaction rate constants were observed for the scission of phenolic O-H bonds over the oxygen-deficient surfaces compared to the pristine *** negative effects caused by the oxygen-deficient conditions could be attributed to the local reduction of FeⅢto FeⅡ,which lower the oxidizing ability of surface reaction *** findings of this study provide us a promising approach to regulate the formation of EPFRs.

关键词： EPFR formation Phenol dissociation Oxygen-vacancy impact Hematite surface First-principles calculation

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薛晓明辨治顽固性咳嗽的临证经验

中国民间疗法 2024年第11期32卷 40-42,116页

作者：张晔陈晶晶薛晓明孟丽红李典乔文晓山西中医药大学山西太原030024 山西省中医院山西太原030012 山西省中医药研究院山西太原030012

该文介绍薛晓明教授治疗顽固性咳嗽的独到经验。薛晓明教授认为,治疗顽固性咳嗽应以辨风邪为先导,以辨寒热为纲目,以改善咽部不适为切入点,以活血化瘀为基点。

关键词：顽固性咳嗽风邪止嗽散温肺散寒止咳汤清肺止咳化痰方咽部不适薛晓明

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相控圆弧阵声源在TI地层井孔中产生的声场

声学学报 2016年第3期41卷 315-320页

作者：王瑞甲乔文孝中国石油大学油气资源与探测国家重点实验室北京102249 北京市地球探测与信息技术重点实验室北京102249

研究了相控圆弧阵声源在各向异性地层井孔中产生的声场的特征,重点分析了该声源对于地层横波各向异性的方位敏感性,旨在探索一种新的地层声学各向异性测量方法。结果显示:相控圆弧阵声源在地层中可激发多种方位阶数的声场,主要成分为单... 详细信息

研究了相控圆弧阵声源在各向异性地层井孔中产生的声场的特征,重点分析了该声源对于地层横波各向异性的方位敏感性,旨在探索一种新的地层声学各向异性测量方法。结果显示:相控圆弧阵声源在地层中可激发多种方位阶数的声场,主要成分为单极子波场和偶极子波场;在HTI地层竖直井中,方位角不同的圆弧阵声源激发的波动的速度不同,相控圆弧阵声源对于地层横波速度的方位各向异性的敏感性主要是它所激发的弯曲波的贡献。相比于传统的正交偶极子声波测井而言,采用相控圆弧阵声源可以评价井附近地层的周向非均质性,可以提高井周测量覆盖次数,提高反演结果的可靠性。另外,相控圆弧阵声源兼具备多极子声源的功能,优化的相位控制方式可以实现方位各向异性的最佳测量。

关键词： TI 相控井孔横波速度声波测井波场覆盖次数非均质偶极子单极子

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套管井中相控线阵声源激发的声场研究

声学学报 2007年第4期32卷 328-332页

作者：陈雪莲乔文孝中国石油大学(华东)地球资源与信息学院山东257061 中国石油大学(北京)资源与信息学院北京102249

利用相控线阵声源的动态声束偏转技术可大大增强套管井孔中有用模式波的幅度。通过实轴积分方法计算了相控线阵声源在多种胶结状况下的充液套管井中的声场,计算结果表明在Ⅰ、Ⅱ界面均胶结良好时随着相控线阵阵元间激励延迟时间的增加,... 详细信息

利用相控线阵声源的动态声束偏转技术可大大增强套管井孔中有用模式波的幅度。通过实轴积分方法计算了相控线阵声源在多种胶结状况下的充液套管井中的声场,计算结果表明在Ⅰ、Ⅱ界面均胶结良好时随着相控线阵阵元间激励延迟时间的增加,地层滑行纵波和滑行横波的幅度逐渐增强,当相控线阵声源的声束偏转角先后等于地层第一临界角和第二临界角时可使滑行纵波和滑行横波幅度分别加强到最大;在Ⅰ(或Ⅱ)界面存在微环时,单个点声源激发的套管井全波波形中观测不到地层信息,当采用相控线阵声源做发射器时,通过选择相邻阵元间合适的激励延迟时间,可有效地增强地层滑行纵横波的幅度,同时还可较好的抑制套管波的能量。

关键词：相控线阵点声源套管井声场激发地层信息计算结果延迟时间