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Prevention and forecasting of rock burst hazards in coal mines

Mining Science and Technology 2009年第5期19卷 585-591页

作者： DOU Lin-ming LU cai-ping MU Zong-long GAO Ming-shi State Key Laboratory for Coal Resource and Mine Safety China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

Rock bursts signify extreme behavior in coal mine strata and severely threaten the safety of the lives of miners, as well as the effectiveness and productivity of miners. In our study, an elastic-plastic-brittle model for the deformation and failure of coal/rock was established through theoretical analyses, laboratory experiments and field testing, simulation and other means, which perfectly predict sudden and delayed rock bursts. Based on electromagnetic emission (EME), acoustic emission (AE) and microseism (MS) effects in the process from deformation until impact rupture of coal-rock combination samples, a multi-parameter identification of premonitory technology was formed, largely depending on these three forms of emission. Thus a system of classification for forecasting rock bursts in space and time was established. We have presented the intensity weakening theory for rock bursts and a strong-soft-strong (3S) structural model for controlling the impact on rock surrounding roadways, with the objective of laying a theoretical foundation and establishing references for parameters for the weakening control of rock bursts. For the purpose of prevention, key technical parameters of directional hydraulic fracturing are revealed. Based on these results, as well as those from deep-hole controlled blasting in coal seams and rock, integrated control techniques were established and anti-impact hydraulic props, suitable for roadways subject to hazards from rockbursts have also been developed. These technologies have been widely used in most coal mines in China, subject to these hazards and have achieved remarkable economic and social benefits.

关键词： rock bursts elastic-plastic-brittle model multi-parameter premonitory intensity weakening strong-soft-strong (3S) structure directional hydraulic fracturing anti-impact hydraulic prop

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Effect of nitrogen addition on microstructure and erosion-corrosion behavior of stainless steel in acidic slurry

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China Foundry 2009年第3期6卷 197-201页

作者： Li ping cai Qi zhou Wei Bo kang Li Feng jun School of Material Science and Engineering Henan Polytechnic UniversityJiaozuo 454000HenanChina China Yituo Group Co. Ltd.Luoyang 471004HenanChina School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China China Yituo Group Co.Ltd.Luoyang 471004HenanChina

Effect of nitrogen content on the microstructure and erosion-corrosion (E-C) behavior of stainless steel (containing about 25% Cr, 5%-6% Ni, and 1%-2% Mo) was investigated by using optical microscope(OM), potentiodynamic polarization curve and immersion method, a self-made rotating disk apparatus and scanning electron microscopy (SEM) and so on. The results show that with the increase of nitrogen content from 0 (no adding) to 0.485 wt.%, the Cr(eq)/Ni(eq) ratio of the tested materials decreases from 4.14 to 1.23 and the ferrite volume percentage of the steel tested linearly decreases approximately from 90% to 10%. The effect of nitrogen content on polarization behavior of the studied steel was not significant. All the passive current densities (I(p)) and pure corrosion rates (V(c)) of the different N content specimens in the acidic solution (slurry containing 0.1 M H(2)SO(4)+0.06% Cl(-)+0.4% F(-), the simplified zinc hydrometallurgy slurry) are too low and nearly negligible. Whereas the pure erosion rates (V(e)) of the four scenarios of the steels tested (N content, wt.%: N1, no adding; N2, 0.143%; N3, 0.289%; N4, 0485%, respectively) are much higher than their V(c) values. The V(e) values of the tested steels are in the order of N4 > N1 > N3 > N2, at the same time, the total weight loss rates (V(t)) follow the order of N4 > N1 > N3 > N2, too. N2 steel consisting of approximately equal volume fractions of ferrite (alpha) and austenite (gamma) exhibits the most excellent E-C resistance and erosion resistance, while the stainless steels possessing the big difference between alpha phase and gamma phase, such as N1 steel nearly possessing single ferrite or N4 steel nearly possessing single austenite, show poorer E-C resistance and erosion resistance.

关键词： nitrogen microstructure erosion-corrosion (E-C) duplex stainless steels

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Comparison of the Kinetics of 1-Hexene Metathesis by Ruthenium Carbene Catalysts

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Chinese Chemical Letters 2006年第7期17卷 988-990页

作者： Chen Xi BAI Wen Zhen ZHANG Ren HE Yan Hong SUN Xiao ping cai Research Institute of Jilin Petrochemical Company Ltd. Petrochina Jilin 132021 State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012

A kinetic study of two ruthenium carbene catalysts, （PCy3）2Cl2Ru=CHPh 1 （Grubbs catalyst） and a new catalyst [1,3-bis（2,6-dimethylphenyl）4,5-dihydroimidazol-2-ylidene]（PPh3）（Cl）2Ru-CHPh 3, were conducted in metathesis of 1-hexene. The kinetic behavior of these catalysts at 40, 50, 60 and 70℃ was compared. Complex 3 has the more active catalytic effect at temperatures 40-70℃.

关键词： Ruthenium carbene metathesis.

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Three-dimensional nitrogen-doped graphene hydrogel supported Co-CeOx nanoclusters as efficient catalysts for hydrogen generation from hydrolysis of ammonia borane

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Chinese Chemical Letters 2018年第11期29卷 1671-1674页

作者： Yana Men Jun Su Chaozhang Huang Lijing Liang ping cai Gongzhen Cheng Wei Luo College of Chemistry and Molecular Sciences. Wuhan University Wuhon 430072 China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology Wuhan 430074 China Technical Center of Fujian Tobacco Industrial Co. Ltd. Xiamen 361022 China

The development of highly active noble-metal-flee catalysts for catalytic hydrolysis of ammonia borane is mandatory for its application in hydrogen storage. Herein, Co-CeOx nanoclusters have been successfully anchored on a three-dimensional nitrogen-doped graphene hydrogel （NGH） by a simple coreduction method and further used as efficient catalysts to catalytic hydrolysis of ammonia borane at room temperature. Thanks to the strong synergistic electronic effect between Co and CeOx, as well as the strong metal-support interaction between Co-CeOx and 3D NGH, the as-synthesized Co-（CeOx）0.91/NGH catalyst exhibits superior catalytic activity toward hydrolysis of ammonia borane, with the turnover frequency （TOF） value of 79.5 min 1, which is almost 13 times higher than that of Co]NGH, and higher than most of the reported noble-metal-free catalysts.

关键词： Nitrogen-doped graphene hydrogel Co-CeOx Hydrogen storage Ammonia borane Noble-metal-free

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Recent Progress in All-Solution-Processed Organic Solar Cells

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Chinese Journal of Chemistry 2024年第2期42卷 190-198页

作者： Yixuan Xu Qian Wang Wentao Zou Xu Zhang Yanna Sun Yuanyuan Kan ping cai Ke Gao School of Materials Science and Engineering&Guangxi Key Laboratory of Information Materials Guilin University of Electronic TechnologyGuilinGuangxi 541004China Shandong Provincial Key Laboratory for Science of Material Creation and Energy Conversion Science Center for Material Creation and Energy ConversionInstitute of Frontier and Interdisciplinary ScienceShandong UniversityQingdaoShandong 266237China

All-solution-processed organic solar cells(OSCs)(from the bottom electrode to the top electrode)are highly attractive thanks to their low cost,lightweight and high-throughput ***,achieving highly efficient all-solution-processed OSCs remains a significant *** of the key issues is the lack of high-quality solution-processed electrode systems that can replace indium tin oxide(ITO)and vacuum-deposited metal *** this paper,we comprehensively review recent advances in all-solution-processed osCs,and classified the devices as the top electrode materials,including silver nanowires(AgNWs),conducting polymers and composite conducting *** correlation between electrode materials,properties of electrodes,and device performance in all-solution-processed OSCs is *** addition,the critical roles of the active layer and interface layer are also ***,the prospects and challenges of all-solution-processed OSCs are presented.

关键词： Organic solar cells All-solution-processed organic solar cells Solution-processed electrodes High performance Silver nanowires Conductive polymers Composite conducting materials

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Controlling paths of high-order harmonic generation by orthogonal two-color fields

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Chinese Physics B 2020年第4期29卷 242-245页

作者： Ze-Hui Ma cai-ping Zhang Jun-Lin Ma Xiang-Yang Miao College of Physics and Information Engineering Shanxi Normal UniversityLinfen 041004China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityLinfen 041004China

Controlling paths of high-order harmonic generation from H^2+ is theoretically investigated by numerically solving the time-dependent Schrodinger equation based on the Born-Oppenheimer approximation in orthogonal two-color *** simulations show that the change of harmonic emission paths is dependent on time-dependent distribution of *** with one-dimensional linearly polarized long wavelength laser,multiple returns are suppressed and short paths are dominant in the process of harmonic emission by two-dimensional orthogonal ω/2ω laser ***,not only are multiple returns weaken,but also the harmonic emission varies from twice to once in an optical cycle by orthogonalω/1.5ωlaser *** the time-frequency distributions and the time-dependent electron wave packets probability density,the mechanism of controlling paths is further *** a result,a 68-as isolated attosecond pulse is obtained by superposing a proper range of the harmonics.

关键词： high-order harmonic generation orthogonal two-color fields attosecond pulse generation

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Novel multi-path routing scheme for UWB Ad hoc network

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通信学报 2005年第10期26卷 89-96页

作者： XU ping-ping YANG cai-yu SONG Shu-qing BI Guang-guo National Mobile Communication Research Laboratory Southeast University Nanjing 210096 China

The routing protocols play an important role for ad hoc networks *** some problems with DSR,SMR,and AMR protocols were analyzed,a new routing protocol suitable for UWB Ad hoc networks was proposed in this *** new routing protocol utilize an act of orientation of UWB and tries to get sufficient route information and decrease the network load caused by route discovery at the same *** results show that the routing load of the new protocol is lower and throughput is higher than that of *** the node’s mobility increases,these advantages become more obvious.

关键词：多路技术邮件路由 UWB通信动态系统

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A novel static shape-adjustment technique for planar phased-array satellite antennas

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Acta Mechanica Sinica 2018年第6期34卷 1145-1155页

作者： Ji-Yang Zhou Guang-Yu Lu Guo-ping cai Guang-Qiang Fang Liang-Liang Lv Jun-Wei Shi Department of Engineering Mechanics State Key Laboratory of Ocean EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Institute of Aerospace System Engineering Shanghai 201109China

Planar phased-array satellite antennas deform when subjected to external disturbances such as thermal gradients or slewing *** distortion can degrade the coherence of the antenna and must therefore be eliminated to maintain *** support planar phased-array satellite antennas,a truss with diagonal cables is often applied,generally pretensioned to improve the stiffness of the antenna and maintain the integrity of the structure.A new technique is proposed herein,using the diagonal cables as the actuators for static shape adjustment of the planar phased-array satellite *** this technique,the diagonal cables are not pretensioned;instead,they are slack when the deformation of the antenna is *** using this technique,there is no need to add redundant control devices,improving the reliability and reducing the mass of the *** finite element method is used to establish a structural model for the satellite antenna,then a method is introduced to select proper diagonal cables and determine the corresponding *** simulations of a simplified two-bay satellite antenna are first carried out to validate the proposed ***,a simplified 18-bay antenna is also studied,because spaceborne satellite antennas have inevitably tended to be large in recent *** numerical simulation results show that the proposed technique can be effectively used to adjust the static shape of planar phased-array satellite antennas,achieving high precision.

关键词： Planar phased-array satellite antenna Static shape adjustment Diagonal cables Active control

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Response of axillary bud development in garlic(Allium sativum L.) to seed cloves soaked in gibberellic acid(GA3) solution

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Journal of Integrative Agriculture 2020年第4期19卷 1044-1054页

作者： LIU Hong-jiu HUANG cai-ping TONG Pei-jiang YANG Xue CUI Ming-ming CHENG Zhi-hui College of Horticulture Northwest A&F UniversityYangling 712100P.R.China College of Plant Protection Northwest A&F UniversityYangling 712100P.R.China

Gibberellins(GAs) are important phytohormones that regulate many developmental processes in plants. Clove, as the reproductive organ of garlic, dramatically affected garlic bulb development. Considering the potential of gibberellins in plant development and our previous studies, we investigated the effect of soaking two types of seed cloves(seed clove-I: without root/shoot sprouting;seed clove-II: with root/shoot sprouting) in GA3 solution on axillary bud development and examined the effect of soaking seed cloves in GA3 solution on bulb development, phytohormone level and sugar content in this *** indicated seed clove types, soaking liquids and their interaction significantly affected the number of cloves per bulb and the rate of single-clove bulb. Moreover, soaking seed cloves in 1 mmol L^-1 GA3 solution for 24 h not only promoted axillary bud formation and secondary plant growth(equal to tillering or branching), but also slightly increased the number of cloves per bulb and changed bulb structure with a low yield and marketable quality. On the 40 th day after GA3 treatment(at axillary bud outgrowth stage), zeatin riboside(ZR) and soluble protein in stem were sharply increased with the increase of GA3, sucrose, fructose and soluble protein in leaf. However, GA3, indole-3-acetic acid(IAA), soluble sugar and sucrose in stem(3.52 ng g^-1 fresh weight(FW), 19.88 ng g^-1 FW, 237.3 mg g^-1 FW, and 8.24 mg g^-1 FW, respectively) were significantly decreased on the 40 th day after GA3 treatment, compared to the control of water treatment(5.56 ng g^-1 FW, 32.96 ng g^-1 FW, 263.6 mg g^-1 FW, and 10.37 mg g^-1 FW, respectively). To our knowledge, these novel results indicate seed cloves soaked in GA3 solution promotes axillary bud formation and outgrowth that caused the changes in plant architecture and bulb structure. Meanwhile, our findings suggest that the level of endogenous plant hormone(GA3, IAA and ZR) cooperates with the content of sugar(sucrose and fructose)

关键词： garlic(Allium sativum) gibberellic acid seed clove axillary bud plant hormone sugar

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Modifying the Electron Dynamics in High-Order Harmonic Generation via a Two-Color Laser Field

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Chinese Physics Letters 2023年第12期40卷 40-45页

作者：张彩萍苗向阳 College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityTaiyuan 030031China

We investigate the harmonic emission from bichromatic periodic potential by numerically solving the timedependent Schro¨dinger equation in the velocity gauge. The results show that the harmonic minimum is sensitive to the wavelength. Moreover, distinct crystal momentum states contribute differently to harmonic generation. In momentum space, the electron dynamics reveal a close relationship between the spectral minimum and the electron distribution in higher conduction bands. Additionally, by introducing an ultraviolet pulse to the fundamental laser field, the suppression of the harmonic minimum occurs as a result of heightened electron populations in higher conduction bands. This work sheds light on the harmonic emission originating from a solid with a two-atom basis.

关键词： harmonic momentum bands

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