检索结果-南通市图书馆

Mechanism and monitoring and early warning technology for rockburst in coal mines

在线全文

学校读者我要写书评

暂无评论

International Journal of minerals,Metallurgy and Materials 2021年第7期28卷 1097-1111页

作者： Xue-qiu He Chao Zhou Da-zhao Song Zhen-lei Li An-ye Cao Shen-quan He Majid Khan School of Civil and Resources Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory of Ministry of Education for Efficient Mining and Safety of Metal mine University of Science and Technology BeijingBeijing 100083China State Key Laboratory of Coal Resource and mine Safety China University of Mining and TechnologyXuzhou 221116China

On the basis of the massive amount of published literature and the long-term practice of our research group in the field of prevention and control of rockburst,the research progress and shortcomings in understanding the rockburst phenomenon have been comprehensively *** study focuses on the occurrence mechanism and monitoring and early warning technology for rockburst in coal *** showed that the prevention and control of rockburst had made significant ***,with the increasing mining depth,several unre-solved concerns remain *** the in-depth research and analysis,it can be inferred that rockburst disasters involve three main problems,i.e.,the induction factors are complicated,the mechanism is still unclear,and the accuracy of the monitoring equipment and multi-source stereo monitoring technology is *** monitoring and warning standards of rockburst need to be further clarified and *** with the Internet of Things,cloud computing,and big data,a study of the trend of rockburst needs to be ***-more,the mechanism of multiphase and multi-field coupling induced by rockburst on a large scale needs to be explored.A multisystem and multiparameter integrated monitoring and early warning system and remote monitoring cloud platform for rockburst should be explored and ***-reliability sensing technology and equipment and perfect monitoring and early warning standards are considered to be the de-velopment direction of rockburst in the *** research will help experts and technicians adopt effective measures for controlling rock-burst disasters.

关键词： coal mine rockburst mechanism monitoring and early warning technology multiparameter

Study on the chaotic behavior of mining rock seepage system

在线全文

学校读者我要写书评

暂无评论

Mining Science and Technology 2011年第6期21卷 755-759页

作者： Wan Shiwen Xu Jinhai Li Chong State Key Laboratory of Coal Resources and mine Safety School of Mines China University of Mining ＆ Technology Xuzhou 221008 China Shaanxi Lu＇an Mining group Changzhi 046204 China

One dimensional non-steady, non-Darcy flow of water in a rock stratum was reduced into a system described by six ordinary differential equations involving five controlling parameters. Through response computations and time series analysis, chaotic behavior in the reduced system was discussed in details. Firstly, the dynamical response of the reduced system under a set of parameters was calculated, and the power spectrum of the attractor was obtained through fast Lagrangian transformation; then the phase space was reconstructed by fixing embedding dimension to be 6 and delay time to range from 1 to 20, and the correlation dimension of the attractor was calculated based on the curves under the coordinates of logarithm of correlation integral vs. logarithm of covering radius; and lastly, the Lyapunov indices of the attractor were calculated by using Gram-Schmit's orthogonalization method. The results show that the power spectrum of the attractor is continuous; the correlation dimension of the attractor is equal to 2.36; among the Lyapunov indices, LE1, LE2, LE3 are positive, LE5, LE6 are negative, and LE4 fluctuates near zero. All the analysis indicates that there may exist chaos in the system of non-steady, non-Darcy flow.

关键词： Non-Darcy flow Chaos Power spectrum Correlation dimension Lyapunov indices

Crocus sativus *** anti-inflammatory effects and regulates the NLRP3–NF-κB pathway

在线全文

学校读者我要写书评

暂无评论

Acupuncture and Herbal Medicine 2024年第3期4卷 375-385页

作者： Liang Yang Huanhua Xu Qian Hong Nuo Xu Yan Zhang Rui Tao Shuai Li Zizheng Zhang Jiahao Geng Zihan Wang Huizi Hu Yan Dong Zhaoyi Chu Bin Zheng Jinmiao Zhu Ming Geng Yue Gao School of Chemistry and Pharmaceutical Engineering Hefei Normal UniversityHefeiChina National Key Laboratory for the Modernization of Classical and Famous Prescriptions of Chinese Medicine Jiangxi University of Chinese MedicineNanchangChina Huaihai Hospital Affiliated to xuzhou Medical University/PLA 71st group Military Hospital XuzhouChina Beijing Institution of Radiation Medicine BeijingChina

Objective:This study aimed to evaluate the anti-inflammatory effects of petal and stamen extracts of saffron crocus(Crocus sativus)and explore the underlying ***:Local and systemic inflammation models were used to investigate the anti-inflammatory effects of ***.A xyleneinduced inflammation model or lipopolysaccharide(LPS)-induced inflammation model was used in this *** petal and stamen extracts were each administered to the mice in the xylene and LPS models by gavage for 14 d at 0.1 and 0.4 g/kg doses,***-linked immunosorbent assay(ELISA)was used to measure the concentrations of tumor necrosis factor(TNF)-αand interleukin(IL)-1βin mouse *** and eosin(H&E)staining was used to observe the pathological changes in the ear in the xylene-induced inflammation model and in the spleen in the LPS-induced inflammation ***-like receptor thermal protein domain associated protein 3(NLRP3)protein levels within the nuclear factor-kappa B(NF-κB)pathway were assessed using western ***264.7 cells were treated with LPS(5μg/mL)and LPS+***(0.05,0.1,and 0.2 mg/mL)for 24 h,and a Cell Counting Kit-8 was used to measure cell *** in NLRP3 and NF-κB levels were evaluated by western ***:Petal and stamen extracts of *** attenuated the anti-inflammatory effects in local or systemic inflammatory models and repaired pathological changes in the ear in the xylene-induced inflammation model and spleen in the LPS-induced inflammation *** extracts also decreased the concentrations of TNF-αand IL-1βin the mouse serum in the LPS-induced inflammation *** downregulated NLRP3 protein level through the NF-κB pathway and downregulated LC-3 and BECLIN1 in vivo and in *** Cyanide3-ChloroPhenylhydrazone(CCCP)weakened the effects of *** on the NLRP3–NF-κB ***:*** has anti-inflammatory effects and regulates the NLRP3-NF-κB pathway.

关键词： Autophagy Crocus sativus L. Inflammatory NOD-like receptor thermal protein domain associated protein 3 Nuclear factor kappa B

Huge thick conglomerate movement induced by full thick longwall mining huge thick coal seam

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2012年第3期22卷 399-404页

作者： Ma Liqiang Qiu xiaoxiang Dong Tao Zhang Jixiong Huang Yanli School of mines China University of Mining & Technology Xuzhou 221116 China State Key Laboratory of Coal Resources & mine Safety Xuzhou 221008 China China Yongcheng Coal and Electric Power group Corporation Ltd. Yongcheng 476600 China

A discrete elemental method was used to study the thickness of conglomerate layer in a full thick seam mining activities under the influence of the law, pointing out the thickness of the conglomerate at different seam mining, and during the destruction and instability of existing state of laws. At 21141 thick seam mining, the face toward the direction of separation between the thick layer of conglomerate rock and the next bit after reaching its maximum capacity due to pull from the bottom of the plastic zone, formed a stratified and hierarchical down collapse. The shape of caving area is a ''triangular block'', the length of the plastic zone and face advancement from the linear fit between the height of the plastic zone and the advancing face is a quadratic function of distance, while the top layer of thick gravel layer is the overall bending subsidence trend. Tilting the direction of the face, a thick gob of collapsed conglomerate layer is formed in the coal gob entity on both sides of the thick conglomerate at the top of the overall fracture morphology performance, thus forming a mutual extrusion of articulated block structure. The instability, separation and balance of the thick conglomerate layer in the hinged block stope stress leads to abnormal occurrence of rock burst induced by face as the major factor in the accident. This research reveals the form of stress distribution in the destroyed layer of the thick conglomerate rock, analyzes the stope law of coupling for the pressure burst behavior law for the mining work face, and the choice of preventive measures to provide a theoretical basis and implementation.

关键词： Huge thick conglomerateHuge thick coal seamSeparationCollapseRock burst

Directional hydraulic fracturing to control hard-roof rockburst in coal mines

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2012年第2期22卷 177-181页

作者： Fan Jun Dou Linming He Hu Du Taotao Zhang Shibin Gui Bing Sun Xinglin State Key Laboratory of Coal Resources and mine Safety School of MinesChina University of Mining&TechnologyXuzhou 221116China Coal Mining&Designing Branch China Coal Research InstituteBeijing 100013China Jisan Coal mine of Yanzhou Mining Industry group fining 272000China

Hard roof is the main factor that induces *** view of the present obvious weakness of control measures for hard roof rockburst in domestic collieries,the mechanism and field application of directional hydraulic fracturing technology for rock-burst prevention have been investigated in this paper using theoretical analysis and numerical *** results show that the weighting span of the main roof and the released kinetic energy as well as the total elastic energy decreased greatly after the directional fracturing of hard roof with the mining progression,thereby reducing the rockburst hazard degree to coal *** directional hydraulic fracturing technology was carried out in 6305 working face of Jisan Coal mine to prevent *** practices have proved that this technology is much simpler and safer to operate with better prevention effect compared with *** optimizing the operation procedures and developing a new technology of automated high-pressure delivery pipe,the maximum fracturing radius now reaches more than 9 m and the borehole depth exceeds 20 ***,drilling cutting method was applied to monitor the stress of the coal mass before and after the fracturing,and the drill cuttings dropped significantly which indicates that the burst prevention effect of directional hydraulic fracturing technology is very *** research results of this paper have laid a theoretical and practical foundation for the widespread application of the directional hydraulic fracturing technology in China.

关键词： Hard roofRockburstDirectional hydraulic fracturingSimulation

Propagation and sealing efficiency of chemical grouting in a two-dimensional fracture network with flowing water

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2023年第7期33卷 903-917页

作者： Guosheng Zheng Wanghua Sui Gailing Zhang Jiaxing Chen Dingyang Zhang School of Resources and Geosciences Institute of Mine Water Hazards Prevention and Controlling TechnologyChina University of Mining and TechnologyXuzhou 221116China Shandong Provincial Communications Planning and Design Institute group CO. Ltd.Jinan 250031China National Coal mine Water Hazard Prevention Engineering Technology Research Center Suzhou 234000China School of Geology and Geomatics Tianjin Chengjian UniversityTianjin 300380China

In this study, an orthogonal array experiment is conducted by using a transparent fracture network replica. Image processing and theoretical analysis are performed to investigate the model sealing efficiency(SE), factors influencing SE, and the effect of flowing water on propagation. The results show that grout propagation can be classified into three patterns in the fracture network: sealing off, partial sealing,and major erosion. The factors controlling the SE in a descending order of the amount of influence are the initial water flow speed, fracture aperture, grout take, and gel time. An optimal value for the combination of the gel time and grout take(artificial factors) can result in a good SE. The grouting and seepage pressures are measured, and the results reveal that their variations can indicate the SE to some extent. The SE is good when the seepage pressure at each point increases overall;the frequent fluctuations in the seepage pressure indicate a moderately poor SE, and an overall decline in the seepage pressure indicates a major erosion type. The deflection effect of grouting shows an approximately elliptical propagation with the long axis expanding along the wider fracture opening, demonstrating further application in grouting design.

关键词： Fracture network Grouting Propagation Sealing efficiency Physical modeling Deflection effect of grouting

Technology and application of pressure relief and permeability increase by jointly drilling and slotting coal

在线全文

学校读者我要写书评

暂无评论

International Journal of Mining Science and Technology 2012年第4期22卷 545-551页

作者： Lin Baiquan Zhang Jianguo Shen Chunming Zhang Qizhi Sun Chen State Key Laboratory of Coal Resources and mine Safety China University of Mining&TechnologyXuzhou 221008China School of Safety Engineering China University of Mining 6"TechnologyXuzhou 221008China Zhongping Energy Chemical group Pingdingshan 467000China

Difficulties with soft coal seams having a high gas content and high stress levels can be addressed by a technology of pressure relief and permeability *** the seam by auxiliary drilling with a water jet that breaks the coal and slots the coal seam during the process of retreat drilling achieves pressure relief and permeability *** efficiency of gas extraction from a field test,high gas coal seam was *** the theory of pressure relief and permeability increase required analyzing the characteristics of the double power slotting process and the effects of coal pressure relief and permeability *** influence of confining pressure on coal physical properties was examined by using FLAC3D software code to simulate changes of coal stress within the tool destruction *** double power joint drilling method was *** experiments were performed and the effects are *** research shows that there is an ''islanding effect'' in front of the joint double power drill and slotting *** failure strength of the coal seam is substantially reduced within the tool destruction *** depths are increased by 72% and the diameter of the borehole is increased by 30%.The amount of powdered coal extracted from the drill head increases by 17 times when using the new method.A 30 day total flow measurement from the double power drilled and slotted bores showed that gas extraction increased by 1.3 times compared to the standard drilled *** concentrations increased from 30% to 60% and were more stable so the overall extraction efficiency increased by a factor of two times.

关键词： Collaborative drillingDouble powerSlottingPressure relief and permeability increase

The test research on partial relieving pressure for the entry in the deep mine under high stress and friable surrounding rock

在线全文

学校读者我要写书评

暂无评论

Journal of Coal Science & Engineering(China) 2007年第3期13卷 359-361页

作者：杜计平候朝炯朱亚平郝明奎 School of Resources and Safety Engineering State Key Laboratory of Coal Resources and Mine Safety China University Mining and Technology Xuzhou 221008 China xuzhou group Corporation of Coal Mining Industry Xuzhou 221141 China

Based on the geological condition of Zhangxiaolou deep mine in xuzhou mining area, under 986 m in depth, 20.6-31.6 MPa in maximum horizontal principal stress, and friable and fractured surrounding rock, test researches on partial relieving pressure were completed for the entry with U-steel arched yielding support. The relieving pressure parameters, technology process and results of springing blasting by boreholes and excavating pockets in the two sides of entry were introduced. It is demonstrated that springing will not be shaped under the condition of single borehole arrangement after exploded, the arrangement by a group, it will make borehole bottom form springing in 0.6-0.8 m in diameter, that convergence of two sides and roof to floor have some increments by using springing blasting for reliving pressure. This kind of method for reliving pressure is not suitable to use in the deep mine, and that the convergence of two sides obviously declined by excavating pocket in two sides, it can be still used in the entry with metal support, while maintenance of entry in deep mines is difficult, and can not be supported by bolt or bolt with wire mesh.

关键词： deep mine high stress friable and fractured surrounding rock entry springing blasting relieving pressure excavating pocket relieving pressure

A novel method for producing benzene polycarboxylic acids by electrochemical oxidation of Zhaotong lignite in aqueous NaCl solution

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Carbon Resources Conversion 2024年第2期7卷 88-94页

作者： Ze-Zheng Li Wei-Jia Jiang Yu-Gao Wang Zhi-Lei Wang Jun Shen Xian-Yong Wei College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024ShanxiChina School of Basic Medicine Shanxi University of Chinese MedicineJinzhong 030619China Institute of Environmental Science Shanxi UniversityTaiyuan 030031China Shanxi Huayang New Material Technology group Co. Ltd.YangquanShanxi 045000China Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationChina University of Mining&TechnologyXuzhou 221116JiangsuChina

The development of a coal-based synthetic route to produce benzene polycarboxylic acids(BPCAs)is of great importance for the highly efficient utilization of *** this paper,aqueous NaCl^(-)electrolytic system was used to oxidize Zhaotong lignite to prepare *** electrochemical oxidation of lignite in aqueous NaCl solution could produce more BPCAs than that in aqueous NaOH *** aqueous NaCl electrolytic system could in-suit produce a stable OCl^(-),which was synthesized by the combination reaction between Cl_(2)and OH􀀀generated in the anode or cathode,*** in-suit produced OCl^(-)would degrade the organic structures of the lignite dispersing in the electrolyte to generate *** formation of BPCAs could be greatly affected by current density,electrolysis time and the addition amount of NaCl in the electrolytic system,which resulted from that the factors played an important role in the generation of OCl^(-).The coal related model compounds including anthracene and phenanthrene were used to investigate the electrochemical oxidation mechanism of the *** results indicated that the aromatic ring structures in the lignite were attacked by O_(2)•^(-)from the OCl^(-)to afford BPCAs.

关键词： Lignite Benzene polycarboxylic acids Electrochemical oxidation Aqueous NaCl electrolytic system Coal related model compounds