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Logging prediction and evaluation of fracture toughness for the shales in the Longmaxi Formation, Southern Sichuan Basin

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Petroleum 2021年第3期7卷 254-262页

作者： Jian Xiong kaiyuan liu Changyou Shi Xiangjun liu Linlin Huang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina Geophysical Technology Research Center of BGP INC China National Petroleum CorporationChengduChina

The mode-I fracture toughness is of great significance for evaluating the fracturing ability of shale *** this study,the mode-I fracture toughness of the shale in the Lower Silurian Longmaxi Formation,Southern Sichuan Basin was determined with the Cracked Chevron Notched Brazilian Disc(CCNBD).Based on the experimental data,the relationships among the mode-I fracture toughness,the density,the acoustic time and the clay mineral content were *** shale samples for fracture toughness test from cores were commonly limited,the investigation of fracture toughness using well logs was ***,a prediction model was proposed by correlating the fracture toughness with well logs *** results indicate that the fracture toughness of shale samples is from 0.4744 MPa$m1/2 to 1.0607 MPa$m1/2 with an average of 0.7817 MPa$m1/2,indicating that the anisotropy of fracture toughness of the Longmaxi Formation *** clay mineral content and the density have a positive effect on the fracture toughness,whereas the acoustic time plays a negative role on the fracture *** clay mineral content has an important effect on the relationships among fracture toughness,acoustic time and *** prediction model can provide continuous data of mode-I fracture toughness along the wellbore for field hydraulic fracturing operation,and it has certain guiding significance in the exploration and development of oil and gas reservoirs.

关键词： Rock mechanics Longmaxi formation shale CCNBD Mode-I fracture Toughness Prediction method

Influences of bedding characteristics on the acoustic wave propagation characteristics of shales

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Petroleum 2021年第1期7卷 33-38页

作者： Jian Xiong kaiyuan liu Xiangjun liu Lixi Liang Chongyang Zhang State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengduChina Geophysical Technology Research Center of BGP INC. China National Petroleum CorporationChengduChina

The acoustic response characteristics of shales were investigated by the acoustic transmission experiment,which is the basis of solving geological and engineering problems using the seismic or logging information during the process of the exploration and development of shale gas *** on the theory of acoustic wave and the background of acoustic transmission experiment,the initial condition,vibration source condition,boundary condition and stability condition were constructed,and the numerical simulation of acoustic transmission experiment of shales were completed through Matlab *** results show that under the same bedding angle,the acoustic time and attenuation coefficient of shales shown positive correlation with the bedding density;whereas under the same bedding density,the variation laws of the acoustic time and the attenuation coefficient of shales were more complex with the change of the bedding angle,that is,the acoustic time and attenuation coefficient of shales increased first,then decreased and then increased again with the increase of the bedding angle.

关键词： Shale Bedding characteristics Acoustic wave Numerical simulation

The atomic interface effect of single atom catalysts for electrochemical hydrogen peroxide production

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Nano Research 2023年第8期16卷 10724-10741页

作者： kaiyuan liu Pengwan Chen Zhiyi Sun Wenxing Chen Qiang Zhou Xin Gao State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China Advanced Technology Research Institute Beijing Institute of TechnologyJinan 250307China Energy&Catalysis Center School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China China Academy of Ordnance Science Beijing 100089China

Producing hydrogen peroxide(H_(2)O_(2))through an electrochemical oxygen reduction reaction(ORR)is a safe,green strategy and a promising alternative to traditional energy-intensive anthraquinone *** and renewable power could be utilized for onsite and decentralized H_(2)O_(2)production,demonstrating significant application ***,single atom catalysts(SACs)have demonstrated significant advantages in the catalytic production of H_(2)O_(2)in 2e−***,the selectivity of SACs in ORR once puzzled *** article reviews the research on the development and achievements of H_(2)O_(2)production by SACs catalysis in recent ***,the structure-performance relationship is a guide to designing new *** advanced characterization techniques and theoretical calculation methods,researchers have a clearer and more thorough understanding of the impact of the atomic interface of SACs on ORR catalytic *** coordination moiety formed between the active metal center atom and the support seriously determines the selectivity of SACs,mainly manifested in the adsorption of*OOH ***,the atomic interface of metal atoms together with O/N co-coordination exhibit high selectivity and mass activity,and heteroatoms or functional groups on carbon supports present synergistic effects to promote the production of H_(2)O_(2)in 2e−*** and accurate regulation of the atomic interface of SACs directly affects the 2e−ORR performance of the ***,it is important to deeply understand the atomic interface of SACs and contribute to the development of novel catalysts.

关键词： single atom catalysts(SACs) atomic interface effect hydrogen peroxide(H_(2)O_(2))production electrochemical catalysis

ID-OCTA:OCT angiography based on inverse SNR and decorrelation features

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Journal of Innovative Optical Health Sciences 2021年第1期4卷 3-17页

作者： Huakun Li kaiyuan liu Lin Yao Xiaofeng Deng Ziyi Zhang Peng Li State Key Laboratory of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang UniversityHangzhouZhejiang 310027P.R.China

Optical coherence tomography angiography(OCTA)takes the flowing red blood cells(RBCs)as intrinsic contrast agents,enabling fast and three-dimensional visualization of vasculature per-fusion down to capillary level,without a requirement of exogenous fluorescent *** motion-contrast OCTA algorithms have been proposed to effectively extract dynamic blood flow from static tissues utilizing the different components of OCT signals(including amplitude,phase and complex)with various operations(such as differential,variance and decorrelation).Those algorithms promote the application of OCTA in both clinical diagnosis and scientific *** purpose of this paper is to provide a systematical review of OCTA based on the inverse SNR and decorrelation features(ID-OCTA),mainly including the OCTA contrast origins,ID-OCTA imaging,quantification and applications.

关键词： Medical and biological imaging optical coherence tomography angiography(OCTA) motion-contrast multi-features classifier OCTA quantification

Swept source intraoperative OCT angiography

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Journal of Innovative Optical Health Sciences 2021年第1期4卷 91-99页

作者： Ziyi Zhang Tiepei Zhu Tongtong Cao Zhaoyu Gong Lin Yao kaiyuan liu Juan Ye Peng Li State Key Lab of Modern Optical Instrumentation College of Optical Science and Engineering Zhejiang University Hangzhou Zhejiang 310027P.R.China Eye center of the Second Affiliated Hospital College of Medicine Zhejiang UniversityHangzhouZhejiang 310003P.R.China International Research Center for Advanced Photonics Zhejiang University Hangzhou Zhejiang 310027P.R.China

To accurately guide surgical instruments during ophthalmic procedures,some necessary intraoperative depth perception is required,which standard surgical microscopes supply *** optical coherence tomography(iOCT),combining optical coherence to-mography(OCT)technology and surgical microscope,enables noninvasive,real-time and high-resolution cross-sectional ***,though iOCT enables structural imaging,little research has been done on intraoperative *** this work,we presented a swept-source intraoperative OCT angiography(SS-iOCTA)system based on a standard surgical microscope,which provides both structural and angiographic *** feasibility of the proposed SS-iOCTA was confirmed through deep anterior lamellar keratoplasty(DALK)of ex vivo porcine eyes and blood perfusion imaging of in vivo rat ***-resolution intraoperative feedback,including sub-surface structure and angiogram of biological tissue,can be visualized simulta-neously with the SS-iOCTA system,which expand the surgeon's capabilities and could be widely used in clinical surgery.

关键词： Biomedical imaging optical coherence tomography optical coherence tomography angiography ophthalmology deep anterior lamellar keratoplasty

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连续管套管除垢空化射流喷头优化设计与应用

石油机械 2024年第2期52卷 44-49页

作者：刘锴沅大庆油田第三采油厂

采用常规方法解决大庆油田油水井结蜡、结垢严重的问题,以及其射孔层段炮眼附近堵塞等引发的单井产液量下降、水井不吸水等问题,具有施工效率低、费用高、作业周期长的缺点。为此,通过优选空化射流喷嘴类型,开展空化射流靶距和角度的优... 详细信息

采用常规方法解决大庆油田油水井结蜡、结垢严重的问题,以及其射孔层段炮眼附近堵塞等引发的单井产液量下降、水井不吸水等问题,具有施工效率低、费用高、作业周期长的缺点。为此,通过优选空化射流喷嘴类型,开展空化射流靶距和角度的优化研究,计算喷嘴使用参数,再通过数值模拟的方式验证该喷头在小直径连续管套管除垢空化射流的效果;同时,制定炮眼除垢选井原则,优化连续管除垢工艺参数。通过结垢结蜡套管除垢、射孔层段炮眼除垢等现场应用表明,连续管套管除垢空化射流喷头在套管内和射孔层段炮眼除垢效果明显。所得结论可为解决油水采出井套管除垢工具研制与工艺参数优选提供借鉴。

关键词：空化射流喷头套管除垢炮眼除垢结蜡结垢连续管技术

无网格局部Petrov-Galerkin方法在弹塑性断裂力学问题中的应用

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固体力学学报 2009年第1期30卷 48-53页

作者：刘凯远龙述尧尚守平涂传林湖南大学土木工程学院长沙410082 中南勘测设计研究院长沙410082 湖南大学力学与航天航空学院长沙410082

采用无网格局部Petrov-Galerkin方法来分析弹塑性断裂力学问题.这种无网格方法采用移动最小二乘法(MLS)来构造近似试函数和采用Heaviside函数作为加权残值法中的权函数,由于近似函数不满足Kronecker Delta条件,因此采用直接插值法来施... 详细信息

采用无网格局部Petrov-Galerkin方法来分析弹塑性断裂力学问题.这种无网格方法采用移动最小二乘法(MLS)来构造近似试函数和采用Heaviside函数作为加权残值法中的权函数,由于近似函数不满足Kronecker Delta条件,因此采用直接插值法来施加本质边界条件.如果不考虑体力,所形成的整体刚度矩阵只包含局部边界积分,而不包含局部域积分和奇异积分.采用增量Newton-Raphson迭代法来求解弹塑性增量形式的局部Petrov-Galerkin方程.数值算例结果表明,该文方法对于弹塑性断裂力学问题的求解是可行的和有效的,并且所得到的结果具有较好的精度.

关键词：无网格局部Petrov-Galerkin方法 MLS 直接插值法增量Newton-Raphson迭代法

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平行光透过折射率线性变化介质的传播规律

信阳师范学院学报（自然科学版） 2015年第4期28卷 489-492页

作者：刘开源鞍山师范学院物理科学与技术学院辽宁鞍山114007

从光的折射定律出发,研究平行光束在折射率呈横向线性变化的光学介质中的传播规律,给出了光的传播轨迹随着介质的长度、折射率的变化率的改变而呈现的汇聚、发散及成像情况.

关键词：平行光束光学介质折射率线性变化数值模拟

基于PI-Lead控制的永磁同步电机双环位置伺服系统

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电工技术学报 2023年第8期38卷 2060-2072页

作者：杨明刘铠源陈扬洋徐殿国哈尔滨工业大学电气工程及自动化学院哈尔滨150001

为提高位置伺服系统轨迹跟踪精度及极限带宽,该文研究了一种位置-电流双环伺服结构,其位置控制采用结合相位超前环节的比例积分控制器(PI-Lead)。首先,探讨了P-PI-PI和PI-P-PI两种传统三环位置控制结构在轨迹跟踪精度上存在的局限,研究... 详细信息

为提高位置伺服系统轨迹跟踪精度及极限带宽,该文研究了一种位置-电流双环伺服结构,其位置控制采用结合相位超前环节的比例积分控制器(PI-Lead)。首先,探讨了P-PI-PI和PI-P-PI两种传统三环位置控制结构在轨迹跟踪精度上存在的局限,研究了速度前馈提升精度的机理及问题;然后,证明了PI-Lead双环结构相位超前环节对维持系统稳定的意义,详细分析了低通滤波器对系统性能的影响及其参数设计方法,给出了PI-Lead双环位置伺服系统基于闭环频域指标的参数整定策略;最后,对比分析了双环结构与传统三环结构的特点,推导了三种结构的位置极限带宽。实验结果表明,PI-Lead双环结构无需任何前馈补偿即可基本消除系统动态跟踪误差,并具有更高的位置环极限带宽。此外,由于减少了速度控制环节,其无需速度测量且参数整定更加简单。

关键词：永磁同步电机无速度环位置伺服动态跟踪误差参数整定策略