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Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects

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International Journal of Minerals,Metallurgy and Materials 2024年第4期31卷 611-627页

作者： Tao Wang Weiwei ye Liyuan Liu Kai Liu Naisheng jiang Xianhui feng School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Department of Engineering Science University of OxfordParks RoadOxford OX13PJUK School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

This article reviews the current status on the dynamic behavior of highly stressed rocks under ***,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy ***,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in ***,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly ***,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are *** work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions.

关键词： deep rock with high stress highly stressed rock rock failure residual stress energy release

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带蒂颞肌筋膜瓣修补硬脑膜缺损

中华神经医学杂志 2005年第1期4卷 83-84页

作者：江野峰梁庆新何锦庄志浩广东省佛山市中医院神经外科 528000

目的总结带蒂颞肌筋膜瓣修补硬脑膜缺损的应用经验。方法对实施该项手术的56例患者进行回顾性总结。结果术后恢复良好40例,中残8例,重残4例,植物状态1例,死亡3例。没有出现脑嵌顿、皮下积液、脑脊液切口漏、感染和颞肌下坠等并发症。结... 详细信息

目的总结带蒂颞肌筋膜瓣修补硬脑膜缺损的应用经验。方法对实施该项手术的56例患者进行回顾性总结。结果术后恢复良好40例,中残8例,重残4例,植物状态1例,死亡3例。没有出现脑嵌顿、皮下积液、脑脊液切口漏、感染和颞肌下坠等并发症。结论带蒂颞肌筋膜瓣是一种理想的硬脑膜修补材料,具有裁剪方便,手术操作简单等优点。

关键词：颞肌筋膜瓣硬脑膜缺损并发症植物状态术后恢复手术操作嵌顿皮下积液切口患者

Changes in distribution and microstructure of bauxite residue aggregates following amendments addition

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Journal of Environmental Sciences 2019年第4期31卷 276-286页

作者： Shengguo Xue Yuzhen ye feng Zhu Qiongli Wang Jun jiang William Hartley School of Metallurgy and Environment Central South University Crop and Environment Sciences Department Harper Adams UniversityNewport

Bauxite residue is a highly alkaline byproduct which is routinely discarded at residue disposal areas. Improving soil formation process to revegetate the special degraded lands is a promising strategy for sustainable management of the refining industry. A laboratory incubation experiment was used to evaluate the effects of gypsum and vermicompost on stable aggregate formation of bauxite residue. Aggregate size distribution was quantified by fractal theory, whilst residue microstructure was determined by scanning electron microscopy and synchrotron-based X-ray micro-computed tomography. Amendments addition increased the content of macro-aggregates(> 250 μm) and enhanced aggregate stability of bauxite residue. Following gypsum and vermicompost addition, fractal dimension decreased from 2.84 to 2.77, which indicated a more homogeneous distribution of aggregate particles. Images from scanning electron microscopy and three-dimensional microstructure demonstrated that amendments stimulate the formation of improved structure in residue aggregates. Pore parameters including porosity, pore throat surface area, path length, and path tortuosity increased under amendment additions. Changes in aggregate size distribution and microstructure of bauxite residue indicated that additions of gypsum and vermicompost were beneficial to physical condition of bauxite residue which may enhance the ease of vegetation.

关键词： Bauxite residue Fractal characteristics Aggregate microstructure Substrate amendment Soil formation

Microstructure, tensile properties and creep behavior of Al-12Si-3.5Cu-2Ni-0.8Mg alloy produced by different casting technologies

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Journal of Materials Science & Technology 2018年第7期34卷 1222-1228页

作者： Lijie Zuo Bing ye Jian feng Xiangyang Kong Haiyan jiang Wenjiang Ding National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composites Shanghai Jiao Tong University Shanghai 200240 China Institute of Materials for Mobile Energy School of Materials Sdence and Engineering ShanghaiJiao Tong University Shanghai 200240 China

The relationship between the as-cast microstructure and mechanical properties of the ***- 2Ni-0.8Mg alloys produced by permanent mold casting （PMC） and high pressure die casting （HPDC） is investigated. The alloys in both PMC and HPDC consist of Al, Si, A15 Cu2 MgsSi6, Al3 CuNi, and Al Cu4Ni phase. However, the microstructure of the HPDC alloy is significantly refined. Compared to the PMC alloy, the ultimate tensile strength of the HPDC alloy is significantly increased from 244 MPa to 310 MPa, while the elongation shows a reverse trend at room temperature. At low stress and temperature range, slight variations of stress exponent and activation energy indicate that the minimum creep rate is controlled by the grain boundary creep. Then the minimum creep rate is higher for the specimen with the smaller grain size, where grain boundary creep is the dominant creep mechanism. At high stress region, the stress exponent for the PMC alloy and HPDC alloy is 5.18 and 3.07, respectively. The different stress exponents and activation energies measured at high stress and high temperature range indicates that the creep mechanism varies with the casting technologies.2017 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science ＆ Technology.

关键词： Microstructure Tensile properties CreepHigh pressure die casting

Estimation of vector static magnetic field by a nitrogen-vacancy center with a single first-shell ^(13)C nuclear(NV–^(13)C)spin in diamond

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Chinese Physics B 2018年第5期27卷 474-480页

作者： feng-Jian jiang Jian-feng ye Zheng Jiao Zhi-Yong Huang Hai-jiang Lv School of Information Engineering Huangshan University Huangshan 245041 China

We suggest an experimental scheme that a single nitrogen-vacancy（NV） center coupled to a nearest neighbor ^13C nucleus as a sensor in diamond can be used to detect a static vector magnetic field. By means of optical detection magnetic resonance（ODMR） technique, both the strength and the direction of the vector field could be determined by relevant resonance frequencies of continuous wave（CW） and Ramsey spectrums. In addition, we give a method that determines the unique one of eight possible hyperfine tensors for an（NV–^13C） system. Finally, we propose an unambiguous method to exclude the symmetrical solution from eight possible vector fields, which correspond to nearly identical resonance frequencies due to their mirror symmetry about ^14N–Vacancy–^13 C（^14N–V–^13C） plane.

关键词： color centers optical detection magnetic resonance (ODMR) magnetometer

考虑虚拟惯性的VSC-MTDC改进下垂控制策略

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能源工程 2020年第6期40卷 85-90页

作者：钱一辉汪震吴佳良江叶峰高晖胜浙江大学电气工程学院浙江杭州310027 国网江苏省电力有限公司江苏南京210024

针对多端柔性直流(简称多端柔直)系统用于异步互联时各交流电网的频率稳定问题,提出了一种考虑虚拟惯性的多端柔直系统改进下垂控制策略。该控制策略以提高整个系统的惯性水平为目标,利用直流电压建立起交流电网频率和换流站传输的有功... 详细信息

针对多端柔性直流(简称多端柔直)系统用于异步互联时各交流电网的频率稳定问题,提出了一种考虑虚拟惯性的多端柔直系统改进下垂控制策略。该控制策略以提高整个系统的惯性水平为目标,利用直流电压建立起交流电网频率和换流站传输的有功功率之间的联系,使得在单个交流电网因故障而产生频率偏差时,其余交流电网可以提供一定的频率支援能力,在保证直流电压稳定性的前提下改善故障交流电网的频率响应特性。最后,在PSCAD/EMTDC仿真平台上搭建三端柔直系统以验证所提控制策略的有效性。

关键词：多端柔性直流电压下垂控制﹔虚拟惯性频率支援

A New Type of Submerged-Arc Flux-Cored Wire Used for Hardfacing Continuous Casting Rolls

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Journal of Iron and Steel Research International 2011年第11期18卷 74-79页

作者： YANG Ke ZHANG Zhi-xi HU Wang-qin BAO ye-feng jiang Yong-feng College of Mechanical and Electrical Engineering Hohai University Changzhou 213022 Jiangsu China

It is expected that the welding hardfacing of continuous casting rolls has better welding performance and higher wear resistance. A new type of submerged-arc hardfacing flux-cored wire has been developed through nitrogen replacing part of carbon and addition of the nitrogen-fixing elements of niobium and titanium. And microstructure, degree of hardness and high-temperature wear resistance of its deposited metal samples were also investigated. It is found that the microstructure is martensite, residual austenite and carbonitride precipitates. As a result, the hardfacing metal with homogeneous distribution of very fine carbonitride particles had high hardness and excellent wear-re- sisting property during high-temperature wear, which could significantly extend the service life of continuous casting rolls.

关键词： submerged-arc flux-cored wire hardfacing high-temperature wear resistance continuous casting roll

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直流线路功率缺失后受端电网恢复优化模型

信息技术 2020年第2期44卷 28-32页

作者：仇晨光张莉陈刚江叶峰冯树海王珂程锦闽国网江苏省电力有限公司南京210000 南京千智电气科技有限公司南京210019 中国电力科学研究院北京100192

针对直流线路功率缺失后受端电网恢复优化模型难以实现对电网频率偏差、恢复成本及恢复时间等信息的有效控制问题,文中在实施紧急控制切负荷之后,综合考虑紧急控制成本、恢复控制成本以及故障失稳停电成本,提出直流线路功率缺失后受端... 详细信息

针对直流线路功率缺失后受端电网恢复优化模型难以实现对电网频率偏差、恢复成本及恢复时间等信息的有效控制问题,文中在实施紧急控制切负荷之后,综合考虑紧急控制成本、恢复控制成本以及故障失稳停电成本,提出直流线路功率缺失后受端电网恢复优化模型。采用遗传算法在具有单馈入直流接入的IEEE 39节点、及双馈直流接入的IEEE 39节点上进行计算验证,算例结果表明,采用文中优化模型在改善电网频率偏差的同时,可以有效降低电网的恢复成本及恢复时间。

关键词：直流功率缺失受端电网恢复紧急控制负荷恢复

Experimental investigation of vector static magnetic field detection using an NV center with a single first-shell ^(13)C nuclear spin in diamond

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Chinese Physics B 2018年第5期27卷 481-486页

作者： feng-Jian jiang Jian-feng ye Zheng Jiao Jun jiang Kun Ma Xin-Hu Yan Hai-jiang Lv School of Information Engineering Huangshan University Huangshan 245041 China

We perform a proof-of-principle experiment that uses a single negatively charged nitrogen–vacancy（NV） color center with a nearest neighbor ^13C nuclear spin in diamond to detect the strength and direction（including both polar and azimuth angles） of a static vector magnetic field by optical detection magnetic resonance（ODMR） technique. With the known hyperfine coupling tensor between an NV center and a nearest neighbor ^13C nuclear spin, we show that the information of static vector magnetic field could be extracted by observing the pulsed continuous wave（CW） spectrum.

关键词： color centers optical detection magnetic resonance (ODMR) magnetometer