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Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells 被引量:1
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作者 Yukai Zhang Keyong Tian +9 位作者 Wei Wei Wenjuan Mi Fei Lu Zhenzhen Liu Qingwen Zhu Xinyu Zhang Panling Geng Jianhua Qiu Yongli Song Dingjun Zha 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1119-1125,共7页
The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechani... The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period. 展开更多
关键词 apoptosis ATP release Ca2+transients COCHLEA mitochondrial function reactive oxygen species spontaneous electrical activity supporting cells
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Roles of supporting cells in the maintenance and regeneration of the damaged inner ear:A literature review
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作者 Jing-Ying Guo Jun-Yi Xu +1 位作者 Shu-Sheng Gong Guo-Peng Wang 《Journal of Otology》 CAS CSCD 2024年第4期234-240,共7页
The inner ear sensory epithelium consists of two major types of cells:hair cells(HCs)and supporting cells(SCs).Critical functions of HCs in the perception of mechanical stimulation and mechanosensory transduction have... The inner ear sensory epithelium consists of two major types of cells:hair cells(HCs)and supporting cells(SCs).Critical functions of HCs in the perception of mechanical stimulation and mechanosensory transduction have long been elucidated.SCs are indispensable components of the sensory epithelia,and they maintain the structural integrity and ionic environment of the inner ear.Once delicate inner ear epithelia sustain injuries(for example,due to ototoxic drugs or noise exposure),SCs respond immediately to serve as repairers of the epithelium and as adapters to become HC progenitors,aiming at morphological and functional recovery of the inner ear.This regenerative process is extensive in non-mammals,but is limited in the mammalian inner ear,especially in the mature cochlea.This review aimed to discuss the important roles of SCs in the repair of the mammalian inner ear. 展开更多
关键词 EPITHELIUM INJURIES supporting
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Meter-Scale Thin-Walled Structure with Lattice Infill for Fuel Tank Supporting Component of Satellite:Multiscale Design and Experimental Verification
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作者 Xiaoyu Zhang Huizhong Zeng +6 位作者 Shaohui Zhang Yan Zhang Mi Xiao Liping Liu Hao Zhou Hongyou Chai Liang Gao 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期201-220,共20页
Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be f... Lightweight thin-walled structures with lattice infill are widely desired in satellite for their high stiffness-to-weight ratio and superior buckling strength resulting fromthe sandwich effect.Such structures can be fabricated bymetallic additive manufacturing technique,such as selective laser melting(SLM).However,the maximum dimensions of actual structures are usually in a sub-meter scale,which results in restrictions on their appliance in aerospace and other fields.In this work,a meter-scale thin-walled structure with lattice infill is designed for the fuel tank supporting component of the satellite by integrating a self-supporting lattice into the thickness optimization of the thin-wall.The designed structure is fabricated by SLM of AlSi10Mg and cold metal transfer welding technique.Quasi-static mechanical tests and vibration tests are both conducted to verify the mechanical strength of the designed large-scale lattice thin-walled structure.The experimental results indicate that themeter-scale thin-walled structure with lattice infill could meet the dimension and lightweight requirements of most spacecrafts. 展开更多
关键词 Thin-walled structure lattice infill supporting component selective laser melting SATELLITE
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Experimental and Numerical Investigation on the Aerodynamic Characteristics of High-Speed Pantographs with Supporting Beam Wind Deflectors
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作者 Shiyang Song Tongxin Han 《Fluid Dynamics & Materials Processing》 EI 2024年第1期127-145,共19页
Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips,which exacerbates wear and affects the current collection performance of the pantograph-catenary system,a study has been conducted to s... Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips,which exacerbates wear and affects the current collection performance of the pantograph-catenary system,a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics(CFD)simulations.The results demonstrate that the size,position,and installation orientation of the wind deflectors significantly influence the amount of force compensation.They also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards,thereby forming a“π”shape.Moreover,the lift force compensation provided by the wind deflectors increases with the size of the deflector.Alternative wind compensation strategies,such as control circuits,are also discussed,putting emphasis on the pros and cons of various pantograph types and wind compensation approaches. 展开更多
关键词 High-speed pantograph aerodynamic lift force supporting beam wind deflectors computational fluid dynamics(CFD)
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Science and Technology Commissioners Supporting High-Quality Development Project for Hundreds of Counties, Thousands of Towns, and Myriads of Villages in the Context of Rural Revitalization
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作者 Wenwen WEI Cuihong YANG Xiguang ZHU 《Asian Agricultural Research》 2024年第4期1-2,7,共3页
This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization... This paper discusses the important role of science and technology commissioners in the high-quality development of hundreds of counties,thousands of towns,and myriads of villages in the context of rural revitalization,including building bridges,accelerating the transformation of achievements,promoting the value-added of the whole agricultural industry chain,and promoting the rapid development of rural industrial economy.It also discusses the working achievements of science and technology commissioners,in order to promote further development of rural revitalization in Guangdong Province. 展开更多
关键词 SCIENCE and TECHNOLOGY COMMISSIONERS Hundreds of counties thousands of TOWNS and myriads of VILLAGES SCIENCE and TECHNOLOGY support
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Teachers’ Perceptions of the Challenges and Strategies in Supporting Students with Reading Difficulties
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作者 Kristel P.Alcayde Ma.Leticia Jose C.Basilan 《Journal of Contemporary Educational Research》 2024年第8期238-252,共15页
The purpose of this study is to determine the teacher’s perceptions of the challenges and strategies in supporting students with reading difficulties.This study used qualitative method of research and descriptive app... The purpose of this study is to determine the teacher’s perceptions of the challenges and strategies in supporting students with reading difficulties.This study used qualitative method of research and descriptive approach as its research design,in addition to a set of structured interview questions administered through Google Forms to gather data from elementary teachers of Taal Central School,located at Taal Batangas.These structured interview questions were carefully designed to cover various dimensions of the study,including the types of challenges perceived by teachers,strategies employed,and possible solutions for addressing the problems encountered in the process of supporting students with reading difficulties.The results revealed that teachers faced several challenges when teaching students with reading difficulties such as emotional and motivational issues/factors,lack of resources or teaching aids,deficits in knowledge and skills,and problems with student engagement and participation.This study also showed common approaches utilized by the teachers in supporting students with reading difficulties,which were fostering a positive and supportive environment,adopting individualized and multifaceted approaches,and utilizing effective teaching tools and strategies.Lastly,teachers also concluded varied solutions in addressing the challenges perceived in teaching students with reading difficulties towards fostering reading proficiency.These include developing peer support,use of positive reinforcement,and parental involvement.Moreover,specialized resources,professional development for teachers,and specific teaching strategies are also highlighted as crucial components.By integrating these approaches,teachers concluded that it can create a supportive and effective learning environment tailored to the needs of students with reading difficulties. 展开更多
关键词 Reading difficulties Supportive environment Positive reinforcement Parental involvement Professional development
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Corroborative Activities and Recognition Between Community Comprehensive Care Unit’s Nurses and Care Managers in Supporting Discharge of Elderly from Hospital - A Secondary Publication
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作者 Yukie Sakamoto Shizuko Omote +2 位作者 Rie Okamoto Yutaro Takahashi Satomi Ikeuchi 《Journal of Clinical and Nursing Research》 2024年第4期381-392,共12页
Objective: The purpose of this study was to clarify the collaborative activities and mutual recognition between community comprehensive care unit nurses (Ns) and care managers (CM) in supporting the discharge of the e... Objective: The purpose of this study was to clarify the collaborative activities and mutual recognition between community comprehensive care unit nurses (Ns) and care managers (CM) in supporting the discharge of the elderly from the hospital. Methods: A total of 300 nurses working in community comprehensive care wards and 360 care managers working in B City in A Prefecture were surveyed using an anonymous self-administered questionnaire. Results: The highest percentage of responses regarding necessary collaborative activities with multiple professions in supporting hospital discharge were the same for Ns and CMs. The items regarding practice with the highest percentages were “relationship as a team” for Ns, and “user-centered awareness” for CM. While these professionals were willing to share information about their patients’ lives after discharge, the percentage of those explaining their expertise was low. It is thought that collaborative activities focusing on these aspects would lead to more appropriate discharge support. 展开更多
关键词 Discharge support Community comprehensive care ward Ward nurses Care managers Collaborative activities
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慢性心力衰竭患者社会衰弱现状及其影响因素可解释性分析研究 被引量:1
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作者 卢静 孙国珍 +5 位作者 王洁 高敏 于甜栖 孙姝怡 王琴 温高芹 《中国全科医学》 CAS 北大核心 2025年第2期220-227,共8页
背景心力衰竭(简称心衰)合并衰弱的综合管理对衰弱评估提出了多维需求,然而作为心衰患者不良健康结局的增量预测因子,衰弱的社会维度尚未得到充分关注。目的分析慢性心衰患者社会衰弱现状及其影响因素。方法采用便利抽样法,选取2022年9... 背景心力衰竭(简称心衰)合并衰弱的综合管理对衰弱评估提出了多维需求,然而作为心衰患者不良健康结局的增量预测因子,衰弱的社会维度尚未得到充分关注。目的分析慢性心衰患者社会衰弱现状及其影响因素。方法采用便利抽样法,选取2022年9月—2023年7月在南京医科大学第一附属医院心血管内科住院治疗的慢性心衰患者作为调查对象。采用一般资料调查表、社会衰弱量表(HALFT量表,评估社会衰弱)、中文简化版孤独感量表(评估孤独感)、简化版双向社会支持量表(评估社会支持)、个人掌控感量表(PMS,评估个人掌控感)、患者健康问卷(PHQ-9,评估抑郁情况)进行调查。采用单因素分析、支持向量机-特征递归消除进行特征筛选,构建支持向量机分类模型,引入SHAP值进行影响因素分析。结果本研究筛选患者228例,其中8例拒绝填写,共计发放问卷220份,回收有效问卷213份,有效问卷回收率为96.81%。慢性心衰患者中社会衰弱前期及社会衰弱人数占比分别为46.0%(98/213)、17.8%(38/213)。不同社会衰弱情况的慢性心衰患者文化程度、居住地、工作状态、疾病经济负担、个人月收入、病程、运动习惯、就医满意度、交通出行、孤独感量表得分、简化版双向社会支持量表得分、PMS得分、PHQ-9得分比较,差异有统计学意义(P<0.05)。支持向量机-特征递归消除模型性能最佳时,采用最优特征子集(以3∶7拆分样本作为测试集和训练集)构建分类模型后进行SHAP值可解释性分析,模型预测准确率在训练集和测试集中分别为0.73和0.63,此时特征重要性排序及影响方向从高到低为无运动习惯(+)、个人掌控感(-)、疾病经济负担重(+)、双向社会支持(-)、抑郁(+)、孤独感(+)、无业(+)。结论慢性心衰患者中社会衰弱占60%以上,医护人员应对患者的社会功能予以重视,关注患者缺失的社会资源属性及其上游因素,通过强化外部支持系统、培养患者内在信念、克服负性情绪体验,统筹制订管理方案,整合医疗资源实施干预延缓或逆转患者社会衰弱进程,改善其预后及生活质量。 展开更多
关键词 慢性心力衰竭 社会衰弱 影响因素分析 支持向量机 SHAP
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Emerging role of A-kinase anchoring protein 5 signaling in reward circuit function
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作者 William J.Flerlage Mark L.Dell’Acqua +1 位作者 Brian M.Cox Fereshteh S.Nugent 《Neural Regeneration Research》 SCIE CAS 2025年第10期2913-2914,共2页
There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons... There is a strong evidence supporting the hypothesis of synaptic dysfunction as a major contributor to neural circuit and network disruption underlying emotional and mood dysregulation in psychiatric disorders(Simmons et al.,2024).Diverse sets of distinct molecular signaling pathways converge on the synapse to regulate synaptogenesis,synaptic function,and synaptic plasticity in brain regions and circuits through complex interactions organized by numerous multivalent protein scaffolds,including the family of proteins known as A-kinase anchoring proteins(AKAPs). 展开更多
关键词 FUNCTION supporting
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Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
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作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction Supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
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基于Supporting-Ellipsoid方法的自由曲面构造 被引量:3
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作者 顾国超 刘洪波 +1 位作者 陈家奇 高雁 《中国光学》 EI CAS 2014年第5期823-829,共7页
为了在特定平面上获得任意形式的辐照分布,采用了Supporting-Ellipsoid设计方法来构造自由曲面反射镜。介绍了其设计思想和设计过程,并以具体的设计实例为例构建了自由曲面光学系统。仿真结果表明,在不计反射损失的情况下,系统效率达到... 为了在特定平面上获得任意形式的辐照分布,采用了Supporting-Ellipsoid设计方法来构造自由曲面反射镜。介绍了其设计思想和设计过程,并以具体的设计实例为例构建了自由曲面光学系统。仿真结果表明,在不计反射损失的情况下,系统效率达到了97%,较传统太阳模拟器光学系统提升了3倍以上,不均匀度达到5.26%,与理想状态有一定差距,这是因为设计中兼顾了计算时间和自由曲面光滑性所造成的。 展开更多
关键词 supporting-Ellipsoid方法 自由曲面 均匀照明
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敏感环境下地下水池基坑围护施工技术
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作者 苏宇 《山西建筑》 2025年第2期68-71,81,共5页
杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水... 杨树浦水厂深度处理改造工程具有地质条件复杂、场地工况敏感、施工组织及环境保护要求高等特点。结合周边建筑物密集,且离运营中的文保工业建筑最近距离仅为15 m的特点,从支撑选型、回填及降水、土方开挖等方面介绍了敏感环境下地下水池处理改造基坑围护施工技术,有效地保障了重大工程的高效、安全实施,为今后类似环境下地下结构建造涉及到的基坑施工提供了借鉴和参考。 展开更多
关键词 硬咬合排桩 复杂地质 文保建筑 双C环形支撑 基坑开挖 工期高效
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纤维肌痛综合征生物标记物的筛选及免疫细胞浸润分析
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作者 刘雅妮 杨静欢 +5 位作者 陆慧慧 易玉芳 李智翔 欧阳福 吴璟莉 魏兵 《中国组织工程研究》 CAS 北大核心 2025年第5期1091-1100,共10页
背景:纤维肌痛综合征作为常见风湿病,其发病与中枢敏化及免疫异常有关,但具体过程尚未阐明,缺乏特异性诊断标志物,不断探索该病的发病机制具有重要的临床意义。目的:基于加权基因共表达网络分析(WGCNA)等生物信息学方法和机器学习算法... 背景:纤维肌痛综合征作为常见风湿病,其发病与中枢敏化及免疫异常有关,但具体过程尚未阐明,缺乏特异性诊断标志物,不断探索该病的发病机制具有重要的临床意义。目的:基于加权基因共表达网络分析(WGCNA)等生物信息学方法和机器学习算法筛选纤维肌痛综合征潜在的诊断相关标志基因,并分析其免疫细胞浸润特征。方法:对来自基因表达综合数据库(GEO)的纤维肌痛综合征数据集转录谱进行差异分析和WGCNA分析,整合筛选出差异共表达基因,进一步采用机器学习套索回归(LASSO)算法、支持向量机递归特征消除(SVM-RFE)机器学习算法来识别核心生物标志物,并绘制受试者工作特征(ROC)曲线以评估诊断价值。最后,采用单样本基因集富集分析(ssGSEA)和基因集富集分析(GSEA)评估纤维肌痛综合征的免疫细胞浸润情况及通路富集。结果与结论:①对GSE67311数据集按照log2|(FC)|>0,P<0.05的条件进行差异分析后获得8个下调的差异表达基因;进行WGCNA分析后获得正相关性最高(r=0.22,P=0.04)的模块(MEdarkviolet)内含基因497个,负相关性最高(r=-0.41,P=6×10-5)的模块(MEsalmon2)内含基因19个;将差异表达基因与WGCNA的2个高相关性模块基因取交集,获得7个基因。②对上述7个基因进行LASSO回归算法筛选出4个基因,进行SVM-RFE机器学习算法筛选出5个基因,两者取交集后确定了3个核心基因,分别为重组1号染色体开放阅读框150蛋白(germinal center associated signaling and motility like,GCSAML)、整合素β8(Integrin beta-8,ITGB8)和羧肽酶A3(carboxypeptidase A3,CPA3);绘制3个核心基因的ROC曲线下面积分别为0.744,0.739,0.734,提示均具有很好的诊断价值,可作为纤维肌痛综合征的生物标志物。③免疫浸润分析结果显示,与对照组相比纤维肌痛综合征患者记忆B细胞、CD56 bright NK细胞和肥大细胞显著下调(P<0.05),且与上述3个生物标志物显著正相关(P<0.05)。④富集分析结果提示,纤维肌痛综合征的富集途径包括9条,主要与嗅觉传导、神经活性配体-受体相互作用及感染等通路密切相关。⑤上述结果显示,纤维肌痛综合征的发生发展与多基因参与、免疫调节异常及多个通路失调有关,但这些基因与免疫细胞之间的相互作用,以及它们与各通路之间的关系尚需进一步研究。 展开更多
关键词 纤维肌痛综合征 生物信息学 机器学习 免疫浸润 加权基因共表达网络分析 套索回归 支持向量机递归特征消除算法 单样本基因集富集分析 基因集富集分析
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Study on Repairing Permanent Transportation Roadway in Deep Mining by Bolt-Shotcrete and Mesh Supporting 被引量:10
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作者 宋宏伟 鹿守敏 《International Journal of Mining Science and Technology》 SCIE EI 1999年第2期167-171,共5页
The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production... The roadway support in many places of Jiulongkou Colliery, Fengfeng Mining Bureau, such as in the Permanent transportation roadway, was failed or locally caved, which seriously affected the colliery’s coal production performance and safety. Based on analysis of supporting objects for roadway repairing, this paper proposes the supporting parameters and condruction technics. The industrial ted of 70m long roadway repairing shows that the proposed parameters and technics of bolt shotcrete and mesh support for roadway repairing are reasouable, bring good technical and economic results for the colliery, and the repairing is successful. 展开更多
关键词 ROADWAY repairing soft ROCK support bolt-shotcrete supporting broken ROCK zone
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紧邻在建城市轨道交通特别保护区开口基坑支护实践
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作者 吴亮 《山西建筑》 2025年第2期77-81,共5页
基坑北侧距离济南市在建城市轨道交通R2线特别保护区仅1.9 m,特别保护区内严禁支护结构进入,务必在该有限的空间内实现支护桩和止水桩的布置,因此济南市常规的桩锚支护体系难以应用。基坑南侧为先开挖到底的居住地块基坑,因其邻近本基... 基坑北侧距离济南市在建城市轨道交通R2线特别保护区仅1.9 m,特别保护区内严禁支护结构进入,务必在该有限的空间内实现支护桩和止水桩的布置,因此济南市常规的桩锚支护体系难以应用。基坑南侧为先开挖到底的居住地块基坑,因其邻近本基坑侧采用放坡支护,导致本基坑在南侧形成开口,难以满足支撑支点设置要求。通过在居住地块侧设置专门的支撑传力结构作为支座,在解决支撑支点设置问题的同时还增加了地下室的实际使用面积,使本基坑成为R2线特别保护区边首个采用钢管支撑的地下2层深基坑,在确保基坑本身安全的同时,满足了R2线的建设控制要求。 展开更多
关键词 城市轨道交通 特别保护区 基坑支护 钢管支撑 支撑传力结构
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Mechanical properties and supporting effect of CRLD bolts under static pull test conditions 被引量:10
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作者 Xiao-ming Sun Yong Zhang +3 位作者 Dong Wang Jun Yang Hui-chen Xu Man-chao He 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第1期1-9,共9页
A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large d... A device for supporting soft rock masses combined with a constant resistance structure characterized by constant resistance and large deformation at the end of a steel bar, known as the constant resistance and large deformation(CRLD) bolt, has recently been developed to counteract soft rock swelling that often occurs during deep mining. In order to further study the mechanical properties of the CRLD bolt, we investigated its mechanical properties by comparison with the conventional strength bolt(rebar) using static pull tests on many aspects, including supporting capacity, elongation, radial deformation, and energy absorption. The tests verified that the mechanical defects of the rebar, which include the decrease of bolt diameter, reduction of supporting capacity, and emergence and evolution of fracture until failure during the whole pull process, were caused by the Poisson's ratio effect. Due to the special structure set on the CRLD bolt, the bolt presents a seemingly unusual phenomenon of the negative Poisson's ratio effect, i.e., the diameter of the constant resistance structure increases while under-pulling. It is the very effect that ensures the extraordinary mechanical properties, including high resistance, large elongation, and strong energy absorption. According to the comparison and analysis of numerical simulation and field test, we can conclude that the CRLD bolt works better than the rebar bolt. 展开更多
关键词 deep mining BOLTS mechanical properties rock support static pull test
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Iterative FEA Method for Load Distribution of Flexible Supporting Thin-section Ball Bearing 被引量:2
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作者 Ju Shu Liqin Wang +1 位作者 Yuze Mao Yuting Ding 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第1期9-14,共6页
To figure out the load distribution of thin-section rolling bearing supported by flexible structure with squirrel cage and the distribution's influence on bearing life,an iterative FEA method is proposed to use th... To figure out the load distribution of thin-section rolling bearing supported by flexible structure with squirrel cage and the distribution's influence on bearing life,an iterative FEA method is proposed to use the result calculated from the Quasi-Dynamic model based on the rigid support hypothesis. The contact angle,contact position and stiffness of equivalent spring are modified during the iterative FEA to optimize the FEA model,and then the bearings' life can be predicted when the error is below 0.5%. It can be concluded that from the analysis results the load distribution under flexible support is more uniform than that of the rigid support,while the maximum load decreases by 11.2% and bearing life increases by 14.7%. The analysis result of different values of thickness of bearing house,rings and hollow shaft demonstrates the thicknesses of bearing house and hollow shaft have a greater influence on the load's uniformity and bearing's life than those of the rings. 展开更多
关键词 FLEXIBLE SUPPORT with SQUIRREL CAGE ITERATIVE FEA
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Cable-truss supporting system for gob-side entry driving in deep mine and its application 被引量:3
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作者 Yin Qian Jing Hongwen +3 位作者 Dai Dapeng Zhu Tantan Zhao Honghui Meng Bo 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第5期885-893,共9页
In order to solve the large deformation controlling problem for surrounding rock of gob-side entry driving under common cable anchor support in deep mine, site survey, physical modeling experiment, numerical simulatio... In order to solve the large deformation controlling problem for surrounding rock of gob-side entry driving under common cable anchor support in deep mine, site survey, physical modeling experiment, numerical simulation and field measurement were synthetically used to analyze the deformation and failure characteristics of surrounding rock. Besides, applicability analysis, prestress field distribution characteristics of surrounding rock and the control effect on large deformation of surrounding rock were also further studied for the gob-side entry driving in deep mine using the cable-truss supporting system. The results show that, first, compared with no support and traditional bolt anchor support, roof cable-truss system can effectively restrain the initiation and propagation of tensile cracks in the roof surrounding rock and arc shear cracks in the two sides, moreover, the broken development of surrounding rock, roof separation and extrusion deformation between the two sides of the roadway are all controlled; second, a prestressed belt of trapezoidal shape is generated in the surrounding rock by the cable-truss supporting system, and the prestress field range is wide. Especially, the prestress concentration belt in the shallow surrounding rock can greatly improve the anchoring strength and deformation resisting capability of the rock stratum;third, an optimized support system of ‘‘roof and side anchor net beam, roof cable-truss supporting system and anchor cable of the narrow coal pillar" was put forward, and the support optimization design and field industrial test were conducted for the gob-side entry driving of the working face 5302 in Tangkou Mine, from which a good supporting effect was obtained. 展开更多
关键词 Deep mine Gob-side entry driving Cable-truss supporting system Deformation and failure STABILITY
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Application of a combined supporting technology with U-shaped steel support and anchor-grouting to surrounding soft rock reinforcement in roadway 被引量:17
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作者 王辉 郑朋强 +1 位作者 赵文娟 田洪铭 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第5期1240-1250,共11页
Soft rock surrounding deep roadway has poor stability and long-term rheological effect. More and larger deformation problems of surrounding rock occur due to adverse supporting measures for such roadways, which not on... Soft rock surrounding deep roadway has poor stability and long-term rheological effect. More and larger deformation problems of surrounding rock occur due to adverse supporting measures for such roadways, which not only affects the engineering safety critically but also improves the maintenance costs. This paper takes the main rail roadway with severely deformation in China's Zaoquan coal mine as an example to study the long-term deformation tendency and damage zone by means of in-situ deformation monitoring and acoustic wave testing technique. A three-dimensional finite element model reflecting the engineering geological condition and initial design scheme is established by ABAQUS. Then, on the basis of field monitoring deformation data, the surrounding rock geotechnical and theological parameters of the roadway are obtained by back analysis. A combined supporting technology with U-shaped steel support and anchor-grouting is proposed for the surrounding soft rock. The numerical simulation of the combined supporting technology and in-situ deformation monitoring results show that the soft rock surrounding the roadway has been held effectively. 展开更多
关键词 soft rock roadway rheological effect supporting technology numerical simulation REINFORCEMENT
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Upper bound solutions for supporting pressures of shallow tunnels with nonlinear failure criterion 被引量:20
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作者 YANG Xiao-li ZHANG Dao-bing WANG Zuo-wei 《Journal of Central South University》 SCIE EI CAS 2013年第7期2034-2040,共7页
Linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of... Linear failure criterion is widely used in calculation of earth pressure acting on shallow tunnels. However, experimental evidence shows that nonlinear failure criterion is able to represent fairly well the failure of almost all types of rocks, A nonlinear Hock-Brown failure criterion is employed to estimate the supporting pressures of shallow tunnels in limit analysis framework. Two failure mechanisms are proposed for calculating the work rate of extemal force and the internal energy dissipation. A tangential line to the nonlinear failure criterion is used to formulate the supporting pressure problem as a nonlinear programming problem. The objective function formulated in this way is minimized with respect to the failure mechanism and the location of tangency point. In order to assess the validity, the supporting pressures for the proposed failure mechanisms are calculated and compared with each other, and the present results are compared with previously published solutions when the nonlinear criterion is reduced to linear criterion. The agreement supports the validity of the proposed failure mechanisms. An experiment is conducted to investigate the influences of the nonlinear criterion on collapse shape and supporting pressures of shallow tunnels. 展开更多
关键词 shallow tunnel nonlinear criterion limit analysis supporting pressure failure mechanism
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