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limestone mechanical deformation behavior and failure mechanisms： a review

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Acta Geochimica 2018年第2期37卷 153-170页

作者： Wei li Xianjin An heping li Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China State Engineering Technology Institute for Karst Desertfication Control Guiyang 550001 China University of Chinese Academy of Sciences Beijing 100049China School of Karst Science Guizhou Normal UniversityGuiyang 550001 China

In this paper, several mechanical deformation curves of limestone are reviewed, and the effects of temperature, confining pressure, and fluid are discussed. Generally, Mohr–Coulomb is used for limestone brittle fracture. The characteristic of low temperature cataclastic flow and the conditions and constitutive equations of intracrystal plastic deformation such as dislocation creep,diffusion creep, and superplastic flow are discussed in detail. Specifically, from the macroscopic and microscopic view, inelastic compression deformation(shear-enhanced compaction) of large porosity limestone is *** with other mechanics models and strength equations, the dual porosity(macroporosity and microporosity) model is superior and more consistent with experimental data. Previous research has suffered from a shortage of high temperature and high pressure limestone research; we propose several suggestions to avoid this problem in the future:(1) fluid-rock interaction research;(2) mutual transition between natural conditions and laboratory research;(3) the uniform strength criterion forshear-enhanced compaction deformation;(4) test equipment; and(5) superplastic flow mechanism research.

关键词： Mechanical deformation Brittle fracture Ductility failure Strength criterion

时效性激励对脑梗死合并吞咽障碍患者吞咽功能营养状况及神经功能的影响

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临床心身疾病杂志 2024年第3期30卷 76-80页

作者：张佳李和平郑州大学第一附属医院河南郑州450000

目的探讨时效性激励对脑梗死合并吞咽障碍患者吞咽功能、营养状况及神经功能的影响。方法将293例脑梗死合并吞咽障碍患者根据入院建档顺序分为对照组146例和观察组147例。对照组患者给予直接摄食训练,观察组患者在对照组基础上联合时效... 详细信息

目的探讨时效性激励对脑梗死合并吞咽障碍患者吞咽功能、营养状况及神经功能的影响。方法将293例脑梗死合并吞咽障碍患者根据入院建档顺序分为对照组146例和观察组147例。对照组患者给予直接摄食训练,观察组患者在对照组基础上联合时效性激励。观察两组患者干预前后吞咽功能、营养状态[白蛋白(ALB)、前白蛋白(PA)、转铁蛋白(TRF)]、功能恢复情况[美国国立卫生研究院卒中量表(NIHSS)、Barthel指数量表(BI)评分]及并发症。结果干预后两组患者吞咽期通过时间(PTT)、吞咽障碍评分、食管上括约肌(UES)完全开放率以及NIHSS、BI评分均较干预前改善,且观察组优于对照组(P<0.01);两组患者血清ALB、PA、TRF水平均较干预前升高,且观察组高于对照组(P<0.01);观察组患者并发症发生率低于对照组(P<0.01)。结论时效性激励联合直接摄食训练可改善脑梗死合并吞咽障碍患者吞咽功能、神经功能、日常生活能力及机体营养状况,降低并发症发生率。

关键词：时效性激励吞咽障碍摄食训练吞咽功能并发症

Influences of the inner diameter of the solid shielding tube on the characteristics of the radio-frequency cold atmospheric plasma jet

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Plasma Science and Technology 2019年第9期21卷 82-90页

作者： Jing li heping li Department of Engineering Physics Tsinghua University

Active control of the local environment of the cold atmospheric plasma(CAP) jet is of great importance in actual applications since the CAP operates in an open atmosphere with the inevitable entrainment of the surrounding cold air. In this paper, the solid shielding effects of the cylindrical quartz tubes with different inner diameters on the characteristics of the CAP jets driven by a radio-frequency(RF) power supply are studied experimentally. The experimental results show that the total length of the shielded plasma jet can be increased significantly by an appropriate combination of the quartz tube inner diameter and that of the plasma generator nozzle exit with other parameters being unchanged. This phenomenon may be qualitatively attributed to the loss of diffusion of the charged particles in the radial direction under different inner diameters of the quartz tubes. Compared with the plasma free jet, the plasma shielding jet is produced with optimized parameters including longer plasma jet length, higher concentrations of chemically reactive species, higher rotational, vibrational, and electron excitation temperatures when the inner diameters of the solid shielding tube and the generator nozzle exit are the same. A maximum plasma jet length of 52.0 cm is obtained in contrast to that of 5.0 cm of the plasma free jet in this study. The experimental results indicate that the solid shielding effect provides a new method for the active control of the local environment of the RF-CAP jet operating in an open atmosphere.

关键词： cold atmospheric plasma jet radio-frequency glow discharge solid shielding effect effect of the tube inner diameter active control of plasma jet characteristics

An experimental study of interaction between pure water and alkaline feldspar at high temperatures and pressures

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Acta Geochimica 2018年第1期37卷 60-67页

作者： Tao li heping li liping Xu University of Chinese Academy of Sciences Beijing 100049China Laboratory for High Temperature and High Pressure Study of the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 China

Due to the important scientific significance of the interaction between alkaline feldspar and high-temperature and high-pressure fluids. We have conducted a series of autoclave experiments of feldspar dissolution and secondary mineral precipitation in conditions of 250–500℃, 8-50 MPa, and pH = 3.0 and 5.5. Based on the interaction experiments between alkaline feldspar and fluid of high-temperatures and high-pressures, we get the main results as follows:(1) The law that people have grasped below the critical point about the influence of temperature, pressure, and pH value on the alkaline feldspar dissolution behavior is still held above the critical point.(2) Due to the experimental techniques of autoclave flip 180°—sharp quenching and based on electron microprobe analysis of mineral new formed, theoretical analysis has determined that the new altered minerals distributed on the island dissolution surface of feldspar are products of precipitation on a feldspar surface after saturation of the relative ion concentration in water fluid.

关键词： Alkaline feldspar Autoclave High-temperature and high-pressure experiments

基于改进YOLOv5的Video SAR动目标检测算法

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科技创新与应用 2024年第26期14卷 54-59页

作者：白浩琦李和平中国科学院空天信息创新研究院北京100094 中国科学院大学电子电气与通信工程学院北京100049

视频合成孔径雷达图像中动目标阴影可反映其真实位置,针对目前利用深度学习检测阴影的方法来检测动目标存在检测概率低和虚警等问题,提出一种改进的YOLOv5模型。该算法以YOLOv5框架为基础,一方面添加小目标检测层、引入兼顾通道和空间... 详细信息

视频合成孔径雷达图像中动目标阴影可反映其真实位置,针对目前利用深度学习检测阴影的方法来检测动目标存在检测概率低和虚警等问题,提出一种改进的YOLOv5模型。该算法以YOLOv5框架为基础,一方面添加小目标检测层、引入兼顾通道和空间的三维注意力机制,并调整损失函数计算方法为最小点距交并比方法,来提升网络对动目标阴影的感知能力;另一方面增加道路提取作为判定条件,来降低道路外侧静止物体阴影对检测动目标阴影的干扰。经实验验证,该算法与YOLOv5相比在平均精度上提高7.12%,满足动目标检测需求。

关键词：视频SAR 运动目标检测深度学习 YOLOv5 阴影检测

收缩型历史城镇的系统风险评估及保护路径——以渝东地区典型历史城镇为例

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规划师 2024年第4期40卷 32-39页

作者：李和平高黎月林涛赖文韬重庆大学建筑城规学院、自然资源部国土空间规划监测评估预警重点实验室、山地城镇建设与新技术教育部重点实验室北京清华同衡规划设计研究院有限公司西北分公司重庆大学建筑城规学院成都市规划设计研究院

在分析收缩型历史城镇系统风险构成的基础上,探索收缩型历史城镇系统风险评估方法,并以渝东地区典型历史城镇为例开展评估。结果显示,收缩型历史城镇整体上呈现“功能—物质—文化”螺旋式负向转化的规律,个体呈现“空心化、异质化、弃... 详细信息

在分析收缩型历史城镇系统风险构成的基础上,探索收缩型历史城镇系统风险评估方法,并以渝东地区典型历史城镇为例开展评估。结果显示,收缩型历史城镇整体上呈现“功能—物质—文化”螺旋式负向转化的规律,个体呈现“空心化、异质化、弃置化”的风险分异特征,并分别引发了活力、特色、消亡的危机。根据评估结果,从要素分类治理、风险分级响应两个方面提出收缩型历史城镇的保护路径,以期为破解历史城镇收缩困境、化解其系统风险提供借鉴。

关键词：收缩型历史城镇系统风险评估保护路径渝东地区

维普期刊数据库博看期刊

Electrochemical behavior of pyrite in acidic solution with different concentrations of NaCl

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Chinese Journal Of Geochemistry 2014年第4期33卷 374-381页

作者： liN Sen liU Qingyou li heping Laboratory for High Temperature & High Pressure Study of the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The role of chloride ions in metal sulfides leaching has been well established by researchers, the complexation of chloride ions was considered to be the main effect of chloride ions. In this work, the complexation of chloride ions was neglected by addition of EDTA, a strong complexing agent. In this way, further study was conducted on the effect of chloride ions. The increase of chloride ions concentration from 0 to 2 mol/L, decreased the open circuit potential of pyrite from 264 to 91 m V. Unless otherwise stated, all potentials in this paper are based on the potential of saturated calomel electrode. At 600 m V, the increase of chloride ions concentration acceleraed pyrite oxidation; at 800 and 1000 m V, however, the increase of chloride ions concentration lowered pyrite oxidation rate, and the proportion of elemental sulfur was also decreased with increasing chloride ions concentration; when chloride ions concentration increased from 0 to 2 mol/L, the proportion of elemental sulfur decreased from 32% to 28.4% at 800 m V, and 7.1% to 2.4% at 1000 m V.

关键词：氯离子浓度黄铁矿电化学行为酸性溶液氯化钠金属硫化物络合剂研究人员

Characteristics of a radio-frequency cold atmospheric plasma jet produced with a hybrid cross-linear-field electrode configuration

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Plasma Science and Technology 2019年第5期21卷 102-112页

作者： Jing li heping li Department of Engineering Physics Tsinghua University

Cold atmospheric plasma(CAP)jet has wide applications in various fields including advanced materials synthesis and modifications,biomedicine,environmental protection and energy saving,*** control on the volume,temperature and chemically reactive species concentratio ns of the CAP jet is of great importance in actual *** this paper,an radio-frequency atmospheric-pressure glow discharge(RF-APGD)plasma generator with a hybrid cross-linear-field electrode configuration is *** experimental results show that,with the aid of the copper mesh located at the downstream of the traditional co-axial-type plasma generator with a cross-field electrode configuration,a linear field between the inner powered electrode of the traditional plasma generator and the copper mesh can be *** linerfield can,to some extent,enhance the discharges at the upstream of the copper mesh,resulting in small increments(all less than 12.5%)of the species emission intensities,electron excitation temperatures and gas temperatures by keeping other parameters being *** due to the intrinsic transparent and conducting features of the grounded copper mesh to the gas flowing,electric current and heat flux of the plasma plumes,a plasma region with higher concentrations of chemically reactive species and larger plasma plume diameters is obtained at the downstream of the grounded copper mesh on the same level of the gas temperature and electron excitation temperature compared to those of the plasma free *** addition,the charged particle number densities at the same downstream axial location of the grounded copper mesh decrease significantly compared to those of the plasma free *** means that the copper mesh is also,to some extent,helpful for separating the chemically reactive neutral species from the charged particles in side a plasma *** preceding results indicate that the cross-linear-field electrode configuration of the plasma generator

关键词： cold atmospheric plasma hybrid-cross-linear-field electrode configuration grounded copper mesh plasma jet characteristics modulation

Full length cDNA cloning and expression analysis of annexinA2 gene from deer antler tissue

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Journal of Forestry Research 2014年第4期25卷 953-957页

作者： li Hao Xianghong Xiao heping li College of Wildlife Resource Northeast Forestry University

ANXA2（AnnexinA2）, a calcium-dependent phospholipid bind- ing protein, is involved in various Ca2＋-related biological activities. In the present study, full-length cDNA of ANXA2 was isolated from the velvet antler tip tissue of sika deer （Cervus nippon hortulomm）; the amino acid sequence and gene expression was analyzed by using bioinformatics and real-time reverse transcdptase polymerase chain reaction （RT-PCR） techniques. Nucleotide sequence analysis reveals that the full-length cDNA of the ANXA2 gene was 1372 bp, of which 1020 bp was in the opan-reading frame （OR.F） encoding 339 amino acids; its relative mo- lecular weight was 38.3 kDa; and isoelectrie point was 6.72. Sequence analysis indicates that the protein includes four conserved tan- dem-duplication ANX domains. The gene-aceession nucleotide sequence number in GenBank is JX315571. Expression analysis by RT-PCR re- veals that ANXA2 gene expression has a significant positive correlation with the antler-tissue mineralization process, indicating that this gene may play an important role in the regulation of antler-tissue mineraliza- tion.

关键词： velvet antler AnnexinA2 (ANXA2) gene cDNA library clone real-time quantitative RT-PCR