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Stability analysis and control technology of gob‑side entry retaining with double roadways by flling with high‑water material in gently inclined coal seam

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International Journal of Coal Science & Technology 2022年第4期9卷 147-164页

作者： Shengrong Xie en wang Dongdong Chen hui Li Zaisheng Jiang Hongzeng Yang School of energy and Mining engineering China University of Mining and Technology-BeijingBeijing 100083China Beijing Key Laboratory for Precise Mining of Intergrown energy and Resources China University of Mining and Technology-BeijingBeijing 100083China Department of Civil engineering University of British ColumbiaVancouverBC V6T 1Z4Canada Hebei Coal Science Research Institute Corporation Ltd. Xingtai 054000China

To ameliorate the defects of insufcient support resistance of traditional roadside flling bodies for gob-side entry retaining(GER),overcome the inability to adapt to the deformation of surrounding rock,and isolate the goaf efectively,a new type of high-water material as a roadside flling body for GER technology with double roadways was *** instability analysis and control technology of GER with double roadways by flling high-water material into a gently inclined coal seam were *** basic mechanical properties of the new high-water material were investigated through laboratory experiments,and their main advantages were *** reasonable width of the roadside flling wall of a high-water material was obtained by combining ground pressure observation and theoretical *** distribution characteristics of the stress and plastic zone of surrounding rock of GER after being stabilized by the disturbance of the working face were studied using numerical simulations,and the failure range of GER by flling with high-water material was *** on this,a coupling control technology of anchor cables and bolts+single props+metal mesh+anchor bolts is *** the coupling methods of arranging borehole peeping and observing the convergences of surrounding rock,the results demonstrate that GER with double roadways by flling with a 1.8-m-wide high-water material has a good control *** above research will play an active role in promoting the application of high-water materials in GER roadside flling.

关键词： High-water material Gob-side entry retaining with double roadways Stability analysis Gently inclined coal seam Control technology

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基于半导体桥芯片的钝感高瞬发底火设计

火工品 2025年第1期 7-12页

作者：牛惠媛任炜褚恩义李慧常英珂金豪杰陕西应用物理化学研究所瞬态化学效应与控制全国重点实验室陕西西安710061 杭州电子科技大学微电子研究院浙江杭州310018

针对超高速射武器弹药对高频高安全及高一致性点火的发展需求,基于半导体桥芯片点火技术,设计了一种新型钝感高瞬发底火。通过对比研究4种半导体桥芯片及其2种封装结构,选用斯蒂芬酸铅和亚铁氢化铅/高氯酸钾作为两级复合装药,优化形成... 详细信息

针对超高速射武器弹药对高频高安全及高一致性点火的发展需求,基于半导体桥芯片点火技术,设计了一种新型钝感高瞬发底火。通过对比研究4种半导体桥芯片及其2种封装结构,选用斯蒂芬酸铅和亚铁氢化铅/高氯酸钾作为两级复合装药,优化形成了模块化结构的半导体桥底火样机。该底火满足了与弹药接口的匹配要求,并达到1 A 1 W 5 min不发火的安全性要求。发火性能试验表明,所研制的半导体桥底火作用时间不大于200μs,散布不大于30μs,与传统桥丝电底火相比瞬发度和作用时间一致性显著提高,综合性能更好。

关键词：底火半导体桥模块化设计高瞬发高安全

On water in nominally anhydrous minerals from mantle peridotites and magmatic rocks

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Science China Earth Sciences 2016年第6期59卷 1157-1172页

作者： hui HeJiu XU YongJiang PAN Ming'en State Key Laboratory for Ore Deposit Research School of Earth Sciences and Engineering Nanjing University

Trace amount of water associated with the lattice defects of nominally anhydrous minerals （NAMs） can be measured using Fourier transform infrared spectroscopy （FTIR） and secondary ion mass spectrometry （SIMS）. Lots of data on water in NAMs from different lithologies, especially mantle peridotite xenoliths, have been published. The water distribution in olivine from peridotite xenoliths often displays a diffusion profile with high water concentration in the core and low at the rim, which indicates water loss via diffusion during the ascent of host magma. On the other hand, water is homogeneously distributed in pyroxene and its concentration is typically interpreted to represent a mantle value. The water concentration of magma in equilibrium with NAM can be estimated using specific partition coefficient, from which the water content of parental magma and the mantle source can be inferred. The accuracy of this method, however, depends on the selection of appropriate partition coefficient for the system. Using hydrogen isotope compositions and H2O/Ce ratios of mantle NAMs, water source regions can be traced and water heterogeneity can be mapped in the upper mantle. Water plays an important role in the stability of cratonic mantle. The water contents and vertical distribution patterns can be significantly different among different cratonic manties, which may result from different geologic activities. However, the mantle-plume interaction may not necessarily result in significant change of water content in cratonic mantle. The estimation of the water content in the upper mantle is still largely based on geochemical models due to the limitations of data on water in mantle NAMs.

关键词： Nominally anhydrous minerals Fourier transform infrared spectroscopy Craton stability Water in the upper mantle Magma ascent rate Water in magma

Reconstructed rheometer for direct monitoring of dewatering performance and torque in tailings thickening process

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1430-1437页

作者： Yong wang Ai-xiang Wu Zhu-en Ruan Zhi-hui wang Zong-su Wei Gang-feng Yang Yi-ming wang School of Civil and Resource engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of the Ministry of Education of China for High-Efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Section for Biological and Chemical engineering Department of EngineeringAarhus UniversityHangøvej 2DK-8200Aarhus NDenmark

To further clarify the dewatering performance and torque evolution during the tailings thickening process,a self-made rake was connected to a rheometer to monitor the shear stress and *** dewatering performance of the total tailings was greatly improved to a solid mass fraction of 75.33%in 240 *** dewatering process could be divided into three stages:the rapid torque growth period,damping torque growth period,and constant torque thickening *** machine restart was found to have a significant effect on the rake torque;it could result in rake ***,the simultaneous evolution of the torque and solid mass fraction of thickened tailings was analyzed.A relationship between the torque and the solid mass fraction was established,which followed a power *** the experimental and theoretical results provide a reference for the deep cone thickener design and operation to enhance the dewatering performance.

关键词： tailings dewatering rake reconstructed rheometer torque monitoring

Nano-TiO_2 Decorated Radial-Like Mesoporous Silica: Preparation,Characterization, and Adsorption-Photodegradation Behavior

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Journal of Materials Science & Technology 2017年第11期33卷 1314-1322页

作者： Tingting Qian Xiaoping Yin Jinhong Li Hong'en Nian hui Xu Yong Deng Xiang wang Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes National Laboratory of Mineral Materials School of Materials Science and Technology China University of Geosciences Qinghai Institute of Salt Lakes Chinese Academy of Sciences

Supported nanocrystalline TiO2 with a diameter of 15–30 nm was prepared from previously synthesized radial mesoporous silica（RMS） by a post-synthesis method. In addition, their adsorption-photocatalytic activity toward the degradation of methylene blue（MB） was determined. RMS was tailor-made with the main template of CTAB and the SiO2 precursor of TEOS through a facile self-assembly process. The structural, morphological and textural properties of the well-designed TiO2/RMS samples were *** RMS structure was retained after loading TiO2, but its surface area and pore diameter decreased as a result of partial pore blocking. The removal activity of MB for TiO2/RMS was significantly higher than that of commercial TiO2 nanoparticles. The optimal TiO2 loading（20 wt%） on the support could achieve the complete removal of MB within 70 min. The prepared TiO2/RMS particles can be easily separated and display good durability after six reaction cycles.

关键词： Radial-like mesoporous silica Nano-TiO2 Adsorption-photocatalytic degradation

The Nonexistence of Expansive Z^d Actions on Graphs

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Acta Mathematica Sinica,english Series 2005年第6期21卷 1509-1514页

作者： en hui SHI Li Zhen ZHOU Department of Mathematics University of Science and Technology of China Hefei 230026 P. R. China Department of Mathematics Suzhou University Suzhou 215006 P. R. China

It is well known that if X is an arc or a circle, then there is no expansive homeomorphism on X. In this paper we prove that there is no expansive Z^d action on X, which answers the two questions raised by us before, In 1979, Mané proved that there is no expansive homeomorphism on infinite dimensional spaces. Contrary to this result, we construct an expansive Z^2 action on an infinite dimensional space. We also construct an expansive Z^2 action on a zero dimensional space but no element in Z^2 is expansive.

关键词： Expansive homeomorphism Arc Circle Group action

Effect of variations in the polar and azimuthal angles of coarse particles on the structure of drainage channels in thickened beds

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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2321-2333页

作者： Cuiping Li Gezhong Chen Zhu’en Ruan Raimund Bürger Yuan Gao Hezi Hou hui wang Key Laboratory of the Ministry of Education of China for High-efficient Mining and Safety of Metal Mines University of Science and Technology BeijingBeijing 100083China Shunde Innovation School University of Science and Technology BeijingFoshan 528399China CI2MA and Departamento de Ingeniería Matemática Facultad de Ciencias Físicas y MatematicasUniversidad de ConcepcionCasilla 160-CConcepciónChile School of Metallurgical and Ecological engineering University of Science and Technology BeijingBeijing 100083China School of Civil and Resource engineering University of Science and Technology BeijingBeijing 100083China

The 3D reconstruction and quantitative characterization of drainage channels and coarse tailings particles in a bed were conducted in this *** influence of variations in the azimuthal angle(θ)and polar angle(φ)of coarse particles on drainage channel structure was analyzed,and the drainage mechanism of the bed was *** showed that water discharge in the bed reduced the size of pores and throat channels,increasing slurry *** throat channel structure was a key component of the drainage ***φandθof particles changed predominantly along the length *** changes inφhad a cumulative plugging effect on the drainage channel and increased the difficulty of water *** rake and rod formed a shear ring in the tailings bed with shear,and theθdistribution of particles changed from disorderly to orderly during the rotation *** drainage channel was squeezed during the shearing process with the change inθ,which broke the channel structure,encouraged water discharge in the bed,and facilitated a further increase in slurry *** findings of this work are expected to offer theoretical guidance for preparing high-concentration underflow in the tailings thickening process.

关键词： tailings thickening coarse particle azimuthal angle polar angle drainage channels

Preparation and Characterization of Cyano-Silicon-Containing Arylacetylene Resins and Their Composites:Dual enhancement Strategy Involving Physical Interfacial Interactions and Chemical Crosslinking

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Chinese Journal of Polymer Science 2024年第11期42卷 1719-1729,I0009页

作者： Chao-en Jin Hua-Mei Zhu Lei wang Fan wang Ya-Ping Zhu Shi-Feng Deng hui-Min Qi Lei Du Key Laboratory of Specially Functional Polymeric Materials and Related Technology of Ministry of Education School of Materials Science and EngineeringEast China University of Science&TechnologyShanghai200237China

Silicon-containing arylacetylene (PSA) resins have broad application prospects because of their excellent heat ***,improving their mechanical properties and interfacial bonding with reinforcement fibers while maintaining heat resistance is a challenge in engineering ***,poly(diethynylbenzene-methylsilyl-3-benzonitrile)(DEB-CN) and poly(diethynylbenzene-methylsilyl-3,6-diethynylcarbazole-3-benzonitrile)(DEC-CN) were synthesized via an isopropylmagnesium chloride lithium-chloride complex (i-PrMgCl·LiCl),overcoming the compatibility problem between cyano groups and Grignard *** cyano and alkyne groups in the resin underwent cyclization to form pyridine,catalyzed by the-NH-moiety in DEC-CN,resulting in extremely high thermal stability (5%weight loss temperature:669.3°C,glass transition temperature>650°C).The combination of cyano dipole-dipole pairing and hydrogen bonding greatly enhanced the resin-fiber interface properties,while the generated pyridine promoted stress relief in the crosslinked network,substantially improving the mechanical properties of the cyano-silicon-containing arylacetylene resin *** flexural strength of quartz fiber cloth/DEC-CN composites was 298.2 MPa at room temperature and 145.9 MPa at 500°C,corresponding to 84.0%and 127.6%enhancements,respectively,over the cyano-free *** cyano-silicon-containing arylacetylene resins exhibited a dual reinforcement mechanism involving physical interfacial interactions and chemical crosslinking,achieving a good balance between thermal stability and mechanical properties.

关键词： Silicon-containing arylacetylene resins Cyano group Heat resistance Composite interfaces Mechanical properties

Highly Oriented Diamond Film Growth by Atomic Force Microscopy

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Chinese Physics Letters 1998年第11期15卷 822-824页

作者： LI Jian-long MenG Ge WU Ke-hui wang en-ge State Key Laboratory for Surface Physics Institute of PhysicsChinese Academy of SciencesBeijing 100080

Diamond thin films are grown with microwave plasma chemical vapor deposition method on silicon(100)substrates from methane/hydrogen gas mixture,and characterized with atomic force microscopy The results show that most of the diamond crystallites are highly oriented with the(100)planes parallel to the silicon *** structures are found in the film,indicating a combination of layer-by-layer and island *** spectrum and x-ray diffraction also confirm the present results.

关键词： Diamond layer island