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修正Hoek-Brown强度准则在钻孔稳定性分析中的应用 被引量:10
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作者 吴顺川 姜日华 +1 位作者 张诗淮 张敏 《岩土力学》 EI CAS CSCD 北大核心 2018年第S2期1-13,共13页
钻孔稳定性分析是深部钻探工程的重要科学问题之一,选择合理的强度准则有助于提高钻孔稳定性预测的准确性,可有效地减少钻孔崩落事件的发生。由于广泛使用的Hoek-Brown准则忽略了中间主应力的影响,应用时无法充分发挥岩石强度潜能。引... 钻孔稳定性分析是深部钻探工程的重要科学问题之一,选择合理的强度准则有助于提高钻孔稳定性预测的准确性,可有效地减少钻孔崩落事件的发生。由于广泛使用的Hoek-Brown准则忽略了中间主应力的影响,应用时无法充分发挥岩石强度潜能。引入一种有效克服诸多经典强度准则的奇异性与非外凸性缺陷的修正Hoek-Brown强度准则,将其应用于水平、垂直和倾斜钻孔稳定性分析中的最小泥浆压力计算,同时与Mohr-Coulomb、Drucker-Prager、Hoek-Brown、3D Hoek-Brown、Mogi-Coulomb和修正Lade准则等经典强度准则预测值进行对比。研究结果表明,修正Hoek-Brown准则与修正Lade、Mogi-Coulomb和3DHoek-Brown准则的预测结果相近,且修正Hoek-Brown预测值与实际工程所用泥浆的相对误差分别为2.1%和0.76%,证明修正Hoek-Brown准则应用于钻孔稳定性分析的适用性与准确性;最小泥浆压力随钻孔深度增加呈线性递增,且受钻孔方位角和倾斜角的影响;Mohr-Coulomb与Hoek-Brown准则所预测的最小泥浆压力值最大,增加了实际工程泥浆的用量,Drucker-Prager准则所预测的最小泥浆压力最小,但给出的预测结果偏于危险,易发生钻孔失稳;基于修正Hoek-Brown准则可得到理论上最佳的钻孔位置(即所需最小泥浆压力值达到最小),为钻井工程师进行钻孔位置优化提供有益参考。 展开更多
关键词 钻孔稳定性 修正Hoek-Brown强度准则 钻孔崩落 最小泥浆压力
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Damage characteristics of thermally treated granite under uniaxial compression: Insights from active and passive ultrasonic techniques 被引量:2
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作者 GUO Pei WU Shun-chuan +1 位作者 jiang ri-hua ZHANG Guang 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第12期4078-4093,共16页
To explore the effects of thermal treatment on cracking processes in granite, granite samples were thermally treated at 25-400 ℃ and then loaded under uniaxial compression. Active ultrasonic testing and passive acous... To explore the effects of thermal treatment on cracking processes in granite, granite samples were thermally treated at 25-400 ℃ and then loaded under uniaxial compression. Active ultrasonic testing and passive acoustic emission(AE) monitoring were combined to monitor the damage characteristics of the samples. The uniaxial compression strength(UCS) of the sample treated at 200 ℃ shows no apparent change compared with that of the nonheated sample, while the UCS increases at 300 °C and decreases at 400 ℃. As the temperature increases from 25 to 400 ℃, the initial P-wave velocity(Vp) decreases gradually from 4909 to 3823 m/s, and the initial Vpanisotropy ε increases slightly from 0.03 to 0.09. As the axial stress increases, ε increases rapidly in the crack closure stage and unstable cracking stage. The attenuation of ultrasonic amplitude spectra also shows an obvious anisotropy. Besides, the main location magnitude of AE events decreases after thermal treatment, and low-frequency AE events and high-amplitude AE events increasingly occur. However, there is insufficient evidence that the treatment temperature below 400 ℃ has a significant effect on the temporal characteristics, source locations, and b-values of AE. 展开更多
关键词 uniaxial compression thermal treatment acoustic emission ULTRASONIC B-VALUE dominant frequency
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10kV配电线路安全运行维护与管理的研究 被引量:2
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作者 姜明凯 李辉光 +1 位作者 黎日华 邓明 《电力系统装备》 2020年第8期100-101,共2页
最近几年,我国社会经济发展极为迅速,很多地方工业用电增长迅速,居民生活用电量也在逐步增加,对配电系统的要求也越来越高.10kV配电网属于社会供电结构中非常重要的环节,由于配电网的分布广泛,走向错综复杂,成为了安全运行难度较高的环... 最近几年,我国社会经济发展极为迅速,很多地方工业用电增长迅速,居民生活用电量也在逐步增加,对配电系统的要求也越来越高.10kV配电网属于社会供电结构中非常重要的环节,由于配电网的分布广泛,走向错综复杂,成为了安全运行难度较高的环节.文章对电力系统10kV配电线路在运行时容易出现的问题进行分析,并将能够提高线路安全运行的维护管理措施列举出来,使配电线路可以安全稳定运行. 展开更多
关键词 电力系统 10KV配电线路 安全运行 维护管理 分析
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Genetic diversity center of cultivated soybean(Glycine max) in China——New insight and evidence for the diversity center of Chinese cultivated soybean 被引量:2
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作者 WANG Li-xia LIN Fan-yun +16 位作者 LI Lin-hai LI Wei YAN Zhe LUAN Wei-jiang PIAO ri-hua GUAN Yuan NING Xue-cheng ZHU Li MA Yan-song DONG Zhi-min ZHANG Hai-yan ZHANG Yue-qiang GUAN Rong-xia LI Ying-hui LIU Zhang-xiong CHANG Ru-zhen QIU Li-juan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2016年第11期2481-2487,共7页
Information on the center of genetic diversity of soybean(Glycine max) will be helpful not only for designing efficient strategies for breeding programs, but also for understanding the domestication and origin of th... Information on the center of genetic diversity of soybean(Glycine max) will be helpful not only for designing efficient strategies for breeding programs, but also for understanding the domestication and origin of this species. Here, we describe an analysis of genetic diversity based on simple-sequence repeat(SSR) variations within a core collection of 2 111 accessions of Chinese soybean landraces. Prior to the diversity assessment, the geographic origin of each accession was mapped. The map was then divided into grids each 2.5° in latitude and 5° in longitude. We found two regions that had higher number of alleles(NA) and greater polymorphic information content(PIC) values than the others. These regions are adjacently located within grid position of 30°–35°N×105°–110°E, which includes the valley of the middle and lower reaches of the Wei River, and the valley of the upper reaches of the Hanjiang River. It was also observed that in many regions, genetic diversity decreased with the increase in distance from the center. Another region, in northern Hebei Province(115°–120°E×40°–42.5°N), was observed having higher diversity than any surrounding regions, indicating that this is a sub-center of soybean diversity. Based on the presented results, the domestication and origin of soybean are also discussed. 展开更多
关键词 Glycine max genetic resources SSRS diversity center DOMESTICATION
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Association of UCP3,APN,and TNF-α Gene Polymorphisms with Type 2 Diabetes in a Population of Northern Chinese Han Patients 被引量:1
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作者 WANG Ling-ling DU Zhen-wu +4 位作者 LIU Jia-nan WU Mei SONG Yang jiang ri-hua ZHANG Gui-zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期255-258,共4页
We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-α-308G/A on the onset and development of T2DM in a Northern Chin... We observed the polymorphism distribution and coaction of uncoupling protein 3(UCP3)-55C/T,adiponectin(APN)+45T/G and tumor necrosis factor(TNF)-α-308G/A on the onset and development of T2DM in a Northern Chinese Han population of 213[100 type 2 diabete(T2DM) patients and 113 health control subjects] by polymerase chain reaction-restriction fragment length polymorphisum(PCR-RFLP) method.Results demonstrate the polymorphism of UCP3-55C/T,APN+45T/G,and TNF-α-308G/A related to T2DM onset and developement.And the individuals carrying UCP3-55T,APN+45G and TNF-α-308A allele had higher T2DM risk.Those results are the first report to evaluate the association of the coaction of UCP3,APN,TNF-α genes polymorphism on T2DM risk and the susceptibility of T2DM in the Northern Chinese Han population. 展开更多
关键词 Uncoupling protein 3(UCP3) Adiponectin(APN) Tumor necrosis factor(TNF)-α Gene polymorphism Type 2 diabete(T2DM) risk
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Microwave-assisted Palladium-micelle-catalyzed Suzuki Cross-coupling Reaction in Water 被引量:1
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作者 LIN Li LI Sheng-hai jiang ri-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期589-591,共3页
A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids(GILs) stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd ... A microwave-accelerated Suzuki coupling procedure was developed via guanidinium ionic liquids(GILs) stabilized Pd-micelle.The Pd micelle/GILs play a key role in enhancing the activity,due to the highly dispersed Pd active sites and the phase transfer function of GILs,which ensures the adsorption of reactants and facilitates the translation of the intermediates to the surface of the micelle. 展开更多
关键词 Microwave irradiating Pd micelle Suzuki reaction Guanidinium ionic liquid
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Immunofluorescent Labeling of Human HepG2 Cells with CdTe Quantum Dot Probe Conjugated with Anti-pan CK MAb
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作者 SUI Yu-jie ZHANG Gui-zhen +5 位作者 WANG Qian WANG Ya-li WU Mei DU Zhen-wu ZHANG Jie jiang ri-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第2期277-281,共5页
A relatively sensitive, specific, and photostable method for the detection of cytokeratin of cancer cells via conjugation with cadmium telluride quantum dots(CdTe QDs) was described. Water soluble CdTe QDs were conj... A relatively sensitive, specific, and photostable method for the detection of cytokeratin of cancer cells via conjugation with cadmium telluride quantum dots(CdTe QDs) was described. Water soluble CdTe QDs were conjugated to anti-pan-cytokeratin(CK) monoclonal antibody(MAb) through coupling reagent [1-ethyl-3-(3-dimethyla- mino propyl)carbodiimide, EDC] and the conjugates were purified by dialysis. The expression of pan CK protein in HepG2 cells was observed by immunocytochemistry and direct immunofluorescence via QDs-Ab conjugates respectively. Fluorescence intensity and photostability of QDs were compared with those of FITC(fluorescein isothiocyanate). The results show that the QDs-Ab conjugates recognized specifically pan CK protein in HepG2 cells. Compared with FITC, CdTe QDs had higher brightness and photostability without obvious photobleaching under continuous exciting light illumination for 30 min and after the placement at room temperature for 3 d. The results indicate that conjugates of CdTe quantum dot with anti-pan CK MAb can be used for labeling cancer cells derived from epithelial tissues, which provides the basis for the detection of circulating tumor cells(CTCs). 展开更多
关键词 Quantum dot Pan-cytokeratin Immunofluorescence labeling Fluorescence photostability
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修正Hoek-Brown准则的等效Mohr-Coulomb强度参数确定方法研究 被引量:14
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作者 吴顺川 张敏 +1 位作者 张诗淮 姜日华 《岩土力学》 EI CAS CSCD 北大核心 2019年第11期4165-4177,共13页
合理确定岩石材料强度参数是工程设计的关键问题之一。为有效描述岩石的强度特性,众多学者提出了大量三维强度准则,其中基于两参数偏函数的修正Hoek-Brown(H-B)准则取得了良好效果,能够有效地反映岩石的静水压力效应、Lode角效应及中间... 合理确定岩石材料强度参数是工程设计的关键问题之一。为有效描述岩石的强度特性,众多学者提出了大量三维强度准则,其中基于两参数偏函数的修正Hoek-Brown(H-B)准则取得了良好效果,能够有效地反映岩石的静水压力效应、Lode角效应及中间主应力效应等强度特性。确定修正H-B准则的等效Mohr-Coulomb(M-C)参数有利于提高其在工程应用中的便利性,因此提出一种基于I1-√J2平面计算三维强度准则瞬时等效M-C参数的方法,应用于修正H-B准则,并对计算方法的合理性及瞬时等效M-C参数与岩石强度特性的关系进行讨论。结果表明:瞬时等效M-C参数可有效表征非线性静水压力效应,且合理反映Lode角效应和中间主应力效应的区间性特点;瞬时等效M-C参数可有效表征静水压力对Lode角效应的影响和最小主应力对中间主应力效应的影响,静水压力增大时,Lode角效应更为明显,且当最小主应力增大时,瞬时等效内聚力反映出更为显著的中间主应力效应;该方法能够合理地计算瞬时等效M-C参数,修正H-B准则具有准确预测岩石强度的能力。上述成果对修正H-B准则在实际工程中的应用具有较强的指导意义。 展开更多
关键词 三维强度准则 瞬时等效Mohr-Coulomb强度参数 修正Hoek-Brown准则 强度特性
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“互联网+”时代社区智能养老模式分析 被引量:3
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作者 贾俊芳 张叶娥 蒋日华 《山西大同大学学报(自然科学版)》 2023年第1期28-31,共4页
人口老龄化已成为社会各界日益关注的问题,随之而来的养老问题尤为突出。社会的进步和科学的发展使养老服务模式呈现多样性。利用“互联网+”技术、大数据技术、人工智能等技术开发的具有信息化、智能化、可视化养老模式使养老服务更加... 人口老龄化已成为社会各界日益关注的问题,随之而来的养老问题尤为突出。社会的进步和科学的发展使养老服务模式呈现多样性。利用“互联网+”技术、大数据技术、人工智能等技术开发的具有信息化、智能化、可视化养老模式使养老服务更加方便、快捷、周全。从技术层面和设备层面介绍智能养老模式在社区养老中的应用并用模糊K-Means算法对资源配置进行分析,对智能养老模式进行更深一步的研究。 展开更多
关键词 “互联网+”时代 智能养老 养老系统 资源配置
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网络时代高校计算机实验室的建设与维护 被引量:3
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作者 蒋日华 《软件》 2019年第3期130-133,共4页
当今科技快速发展,计算机应用普及到各行各业,高校计算机实验室的有序建设和全面维护,对于培养网络时代与时俱进的大学生发挥着重要作用,它不仅提供了学生学习的环境,还能有效地拓展学生的思维和动手操作能力。从哪些方面着手抓好计算... 当今科技快速发展,计算机应用普及到各行各业,高校计算机实验室的有序建设和全面维护,对于培养网络时代与时俱进的大学生发挥着重要作用,它不仅提供了学生学习的环境,还能有效地拓展学生的思维和动手操作能力。从哪些方面着手抓好计算机实验室建设,是高校共同面对的问题。本文针对目前高校计算机实验室运行遇到的问题,从网络安全意识的不断提升和开放盘符的有效整理、上机课程的科学安排和共享资源的合理配置、网络同传的前期准备和机房屏幕广播软件的配置、考试前期网络安全的合理设置和考试后相关软件的合理取舍等方面对网络时代高校实验室的建设与维护提出了相关的思考,期望有助于更好地发挥高校实验室人才培育功能和社会服务功能。 展开更多
关键词 网络时代 高校实验室 建设 维护
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