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Failure mechanism and control countermeasures of surrounding rock at deep large section chamber intersection in the Wanfu Coal Mine

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Journal of Mountain Science 2023年第7期20卷 2058-2075页

作者： SUN Xiao-ming QI Zhen-min ZHANG Yong MIAO cheng-yu zhao cheng-wei HE Man-chao State Key Laboratory for GeoMechanics and Deep Underground Engineering China University of Mining&Technology BeijingBeijing 100083China School of Mechanics and Civil Engineering China University of Mining&Technology-BeijingBeijing 100083China Institute of Rock and Soil Mechanics Chinese Academy of SciencesWuhan 430060China

In order to solve the problem of large deformation at the intersection of deep large section soft rock roadway,this paper takes the intersection of kilometer-deep roadway in the Wanfu Coal Mine as an engineering example and applies Negative Poisson’s Ratio(NPR)steel anchor cable in roadway support for the first *** combining numerical simulation indoor test,theoretical analysis and field test,the deformation mechanism of surrounding rock at the intersection of deep-buried roadway was analyzed,and the control strategy with micro NPR steel anchor cable as the core was put *** numerical simulation,the numerical analysis model of roadway intersection with different intersection angles and excavation sequence was constructed,and the impact of two key variables of rake angle and excavation sequence on the stability of surrounding rock at roadway intersection was *** optimal dip angle is 90°and the optimal excavation sequence was determined as pump house-pump house *** mechanical properties of the micro-NPR steel anchor cable were studied through the static tensile test in the *** results showed that the micro-NPR steel anchor cable showed high constant resistance,uniform tensile,no yield platform,and no obvious necking phenomenon during *** theoretical derivation,it was calculated that the vertical stress of roadway intersection is 45 MPa,and the bearing capacity of superposed arch composed of micro NPR steel anchor cable is 1257 kN,which is enough to guarantee the overall stability of *** application test and monitoring were carried out on site,and it was verified that the combined support strategy of short and long micro NPR steel anchor cable has a good control effect on large deformation of surrounding rock at intersection,which provides a new support material and support means for the safety and stabilization control of surrounding rock at intersection.

关键词： Mountain tunnel Composite lining Surrounding rock grade Force variation Primary support Secondary lining

咖啡果皮与枯落物覆盖对土壤有机碳组分的影响

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热带作物学报 2024年第7期45卷 1420-1430页

作者：张昂陈苏森谭军林兴军赵青云孙燕董云萍闫林龙宇宙中国热带农业科学院香料饮料研究所/海南省热带香辛饮料作物遗传改良与品质调控重点实验室/农业农村部香辛饮料作物遗传资源利用重点实验室/国家农业科学万宁观测实验站海南万宁571533 云南农业大学热带作物学院云南普洱665000 云南省董云萍专家工作站云南普洱665099 云南省闫林专家工作站云南保山678000

农田土壤有机碳库作为陆地土壤碳库的重要组成部分,其有机碳储量受到种植模式等人为干预的强烈影响。咖啡作为世界热带地区种植面积较大的的经济作物之一,其栽培模式的微小变化即可显著影响陆地生态系统的碳收支平衡。覆盖栽培是咖啡的... 详细信息

农田土壤有机碳库作为陆地土壤碳库的重要组成部分,其有机碳储量受到种植模式等人为干预的强烈影响。咖啡作为世界热带地区种植面积较大的的经济作物之一,其栽培模式的微小变化即可显著影响陆地生态系统的碳收支平衡。覆盖栽培是咖啡的传统栽培模式之一,然而其对咖啡园土壤有机碳组分的影响仍不明确。因此,本研究基于课题组前期使用咖啡果皮与枯落物等咖啡废弃物替代传统覆盖物对咖啡进行覆盖栽培,采用完全随机区组设计,分别设置未覆盖咖啡废弃物(CK)、覆盖咖啡枯落物(L)、覆盖咖啡果皮(P)和覆盖咖啡枯落物+果皮(PL)4种处理;监测咖啡园的土壤微环境、微生物群落多样性及生物量碳、有机碳组分等指标,通过分析土壤微环境、微生物群落结构与有机碳组分之间的内在关系,明确覆盖咖啡废弃物对土壤碳组分的影响及其关键驱动因子。结果显示:覆盖咖啡果皮与枯落物均不影响土壤有机碳、重组有机碳和可溶性有机碳含量,而分别显著提高土壤轻组有机碳含量13.31%和14.12%。覆盖咖啡废弃物不影响土壤微环境指标与微生物群落多样性。覆盖咖啡果皮显著提高土壤微生物量碳14.05%,并且分别显著增加变形菌门(Proteobacteria)和厚壁菌门(Firmicutes)相对丰度18.60%和80.77%,并减少蓝细菌门(Cyanobacteria)相对丰度70.14%,却对土壤真菌群落的影响较小;而覆盖咖啡枯落物分别显著增加变形菌门和厚壁菌门相对丰度14.43%和57.63%,并减少蓝细菌门相对丰度73.43%,同时显著提高真菌子囊菌门(Ascomycota)相对丰度14.79%。本研究中咖啡废弃物覆盖不影响土壤有机碳含量主要归因于重组有机碳等主要土壤有机碳组分对咖啡废弃物覆盖处理不敏感;而咖啡废弃物覆盖引起微生物量碳的提高以及厚壁菌门在土壤微生物群落相对丰度的增加,促进了外源有机碳输入引起的激发效应,是显著提高土壤轻组有机碳含量的主要原因之一。咖啡废弃物短期覆盖显著提高土壤轻组有机碳含量,有助于提升咖啡园土壤碳固存以及为优化咖啡绿色低碳生产模式提供理论支撑。

关键词：咖啡果皮枯落物土壤有机碳组分土壤微生物

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钙镍基单/双金属催化甲壳素热解特性研究

太阳能学报 2024年第8期45卷 628-634页

作者：陈志文崔晓敏程彬海刘晓吉魏威赵明清华大学环境学院北京100084 中节能(肥西)环保能源有限公司合肥231200 清华苏州环境创新研究院苏州215163

以甲壳素为生物质模拟物,采用热重-质谱联用技术研究钙基单/双金属催化热解特性。相比于Ni单金属催化剂,NiFe双金属催化剂的比表面积、平均孔径和孔体积分别提高了309.01%、11.61%和100%,有利于改善热解气与催化剂的接触效果。催化甲壳... 详细信息

以甲壳素为生物质模拟物,采用热重-质谱联用技术研究钙基单/双金属催化热解特性。相比于Ni单金属催化剂,NiFe双金属催化剂的比表面积、平均孔径和孔体积分别提高了309.01%、11.61%和100%,有利于改善热解气与催化剂的接触效果。催化甲壳素热解从易到难排序为Ni、Fe、FeCu=CuNi、Cu、FeNi;催化制氢效果从强到弱排序为Ni>CuNi>FeNi>Cu>FeCu>Fe。Ni单金属有最大产氢峰值,为0.5943 mmol/(g·min),过高温度不利于催化剂发挥活性。Ni和Cu单金属催化剂可增大NH3的析出峰值,分别增大了94.17%和72.96%;提高热解温度有利于NH3的析出,建议催化热解温度不超过600℃。研究探明钙基Ni、Cu、Fe及其双金属催化剂催化生物质(甲壳素)热解特性,并揭示NH3在热解过程中的释放特性。

关键词：生物质甲壳素催化剂单金属催化剂双金属催化剂热解

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Ellipsometric Studies of Polyaniline-Effective Dimension of“Conducting”States

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Chinese Physics Letters 1998年第3期15卷 219-220页

作者： YU zhao-xian lin Yong-yao MO Dang Department of Physics Zhongshan UniversityGuangzhou 510275

A model of fractional-dimensional space is employed to study the measured ellipsometric spectra of polyaniline with acid doping *** from some band parameters,the important dimensional properties of electronic states in the system associated with direct interband transitions can be *** results indicate that as doping density is increased,the effective dimension(D)of electron states in the polyaniline changes from about 1.5D t o near 2.6D,in the same time the polyaniline shows an insulator-metal transition.A brief discussion about the results is given.

关键词： transition doping polyaniline

Guanine-assisted N-doped ordered mesoporous carbons as efficient capacity decaying suppression materials for lithium–sulfur batteries

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Journal of Materials Science & Technology 2022年第6期101卷 155-164页

作者： Riguang cheng Yanxun Guan Yumei Luo Chenchen Zhang Yongpeng Xia Sheng Wei Mengmeng zhao Qi lin Hao Li Shiyou Zheng Federico Rosei Lixian Sun Fen Xu Hongge Pan School of Material Science&Engineering Guangxi Key Laboratory of Information Materials and Guangxi Collaborative Innovation Center of Structure and Property for New Energy and MaterialsGuilin University of Electronic TechnologyGuilin 541004China School of Mechanical&Electrical Engineering Guilin University of Electronic TechnologyGuilin 541004China School of Material Science&Engineering University of Shanghai for Science&TechnologyShanghai 200093China CentreÉnergie Matériaux et TélécommunicationsInstitut National de la Recherche Scientifique1650 Boul.Lionel BouletVarennesJ3×1S2QuébecCanada School of New Energy Science and Technology Xi’an Technological UniversityChina

Lithium–sulfur(Li–S)batteries are considered promising next-generation energy storage devices due to their high weight capacities and theoretical energy densities,which are significantly higher than those of conventional lithium-ion ***,the sulfur cathode presents two major drawbacks,specifically low specific capacity caused by the poor electrical conductivities of the active materials and fast capacity decay caused by polysulfide dissolution/***,a high-rate and high-stability dendritic material consisting of N-doped ordered mesoporous carbons(NOMCs)was successfully synthesized via a facile and low-cost calcination *** highly ordered mesoporous carbon skeleton limited the growth of the sulfur nanofiller within its channels and provided the necessary electrical contact with the insulating ***,N-doped heteroatoms presented strong binding sites for trapping polysulfide intermediates,achieving high electrochemical activity,which promoted polysulfide conversion *** a result,the prepared NOMC-2/S cathode material with 1.2-1.5 mg cm^(-2)of sulfur displayed excellent electrochemical performance with a high-rate capability of 460.5 m Ah g^(-1)at 1 C,a high specific capacity of 530.9 m Ah g^(-1)after 200 cycles at 0.1 C,and a decay rate of~0.19%per cycle.

关键词： Lithium–sulfur batteries N-doped ordered mesoporous carbons Electrochemistry

Effects of Sodium Sulfate as Electrolyte Additive on Electrochemical Performance of Lead Electrode

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Chemical Research in Chinese Universities 2013年第2期29卷 374-378页

作者： YU Jin-yu QIAN zhao-hong zhao Meng WANG Yu-jie NIU lin Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China

Sodium sulfate as an electrolyte additive was studied via electrochemical methods including linear sweep voltammetry（LSV）, cyclic voltammetry（CV） and electrochemical impedance spectroscopy（EIS） to deeply understand its effect on the hydrogen evolution current and overpotential as well as the formation and structure of anodic passi- vation films on lead surface during the redox processes. The results achieved will be valuable to improve the cycle life and maintenance-free properties of lead-acid batteries.

关键词： Electrolyte additive Sodium sulfate Lead electrode Hydrogen evolution reaction Anodic film

不同贮藏方式对黄变发酵萝卜贮藏稳定性的影响

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中国酿造 2024年第4期43卷 186-191页

作者：曾雪晴赵楠杨馨雨林长彬黄巧莲葛黎红四川省农业科学院农产品加工研究所(四川省农业科学院食物与营养健康研究所) 四川成都610066 四川师范大学生命科学学院四川成都610101

为了探究不同包装(真空、盐水)及温度(10℃、20℃、30℃)对黄变发酵萝卜贮藏期间品质的影响,对不同贮存方式的萝卜在贮藏过程中颜色参数、质构及理化指标变化进行分析测定。结果表明,10℃条件下盐水包装能更好稳定萝卜的金黄色泽,延缓萝... 详细信息

为了探究不同包装(真空、盐水)及温度(10℃、20℃、30℃)对黄变发酵萝卜贮藏期间品质的影响,对不同贮存方式的萝卜在贮藏过程中颜色参数、质构及理化指标变化进行分析测定。结果表明,10℃条件下盐水包装能更好稳定萝卜的金黄色泽,延缓萝卜L*值下降、褐变及质构软化。10℃条件下贮藏7 d,盐水包装萝卜L*值、硬度、咀嚼性分别为66.04、10621.81 N、3331.42 mJ,比其他处理组分别高2.93%~31.68%、0.48%~27.65%、3.44%~48.07%;10℃条件下贮藏14 d,盐水包装萝卜还原糖为4.77 g/100 g,比其他组高2.80%~26.19%,细菌对数值降低0.42~0.96 lg(CFU/mL),完全抑制乳酸菌和酵母菌生长。10℃贮藏过程中,盐水包装萝卜pH较稳定,亚硝酸盐未超标(<1.0 mg/kg)且显著低于其他处理(P<0.05)。因此,10℃条件下盐水包装可维持萝卜在贮藏过程中的品质,延缓萝卜褐变,稳定萝卜的金黄色泽和质构。

关键词：黄变发酵萝卜色泽包装方式理化指标贮藏品质

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海委终端IPv6地址分配方式思考

海河水利 2024年第6期 98-101页

作者：谷立成宗华丽赵满胜海河水利委员会水利信息网络中心天津300170

随着全球网络信息技术的加速创新变革和信息化基础设施的快速演进升级,IPv4地址已经无法满足日益增长的互联网需求,加快推进IPv6的规模部署成为加快网络强国建设的迫切要求。探讨了几种常用的终端IPv6地址分配方式及其优缺点,分析了使... 详细信息

随着全球网络信息技术的加速创新变革和信息化基础设施的快速演进升级,IPv4地址已经无法满足日益增长的互联网需求,加快推进IPv6的规模部署成为加快网络强国建设的迫切要求。探讨了几种常用的终端IPv6地址分配方式及其优缺点,分析了使用不同地址分配方式可能面临的问题,可为类似局域网的IPv6地址科学分配提供有价值的参考。

关键词： IPv6地址分配 DHCPv6 SLAAC 有状态地址自动配置

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微型发光二极管全彩色显示研究进展(特邀)

激光与光电子学进展 2024年第1期61卷 420-429页

作者：黄丽香韩冰闫龙赵项杰朱酉良林肖李梓维潘安练湖南大学材料科学与工程学院湖南光电集成创新研究院湖南长沙410082 诺视科技(苏州)有限公司江苏苏州215011

基于发光二极管的显示技术在电视、电脑、手机等终端产品上获得了广泛应用。与传统液晶显示器和有机发光二极管屏幕相比,微型发光二极管(Micro-LED)显示器件在尺寸、性能、功耗、使用寿命等方面均具有显著优势。总结了Micro-LED全彩色... 详细信息

基于发光二极管的显示技术在电视、电脑、手机等终端产品上获得了广泛应用。与传统液晶显示器和有机发光二极管屏幕相比,微型发光二极管(Micro-LED)显示器件在尺寸、性能、功耗、使用寿命等方面均具有显著优势。总结了Micro-LED全彩色显示的技术类别和产品应用场景,综述了实现Micro-LED全彩色显示的最新研究进展,包括巨量转移技术、色转换层集成技术和外延芯片单片集成技术,并进一步比较分析这些技术的优缺点,展望了Micro-LED全彩色显示技术的未来发展。

关键词：发光二极管显示技术单片集成巨量转移氮化镓