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Extracts from rabbit skin inflamed by the vaccinia virus attenuate bupivacaine-induced spinal neurotoxicity in pregnant rats

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Neural Regeneration Research 2013年第11期8卷 983-990页

作者： Rui Cui Shiyuan Xu Liang Wang Hongyi Lei qingxiang cai Hongfei Zhang Dongmei Wang Department of Anesthesiology Zhujiang Hospital of Southern Medical University Department of Anesthesiology Shenzhen Maternity & Child Healthcare Hospital Southern Medical University

Extracts from rabbit skin inflamed by the vaccinia virus can relieve pain and promote repair of nerve injury. The present study intraperitoneally injected extracts from rabbit skin inflamed by the vaccinia virus for 3 and 4 days prior to and following intrathecal injection of bupivacaine into pregnant rats. The pain threshold test after bupivacaine injection showed that the maximum possible effect of tail-flick latency peaked 1 day after intrathecal injection of bupivacaine in the extract-pretreatment group, and gradually decreased, while the maximum possible effect in the bupivacaine group continued to increase after intrathecal injection of bupivacaine. Histological observation showed that after 4 days of intrathecal injection of bupivacaine, the number of shrunken, vacuolated, apoptotic and caspase-9-positive cells in the dorsal root ganglion in the extract-pretreatment group was significantly reduced compared with the bupivacaine group. These findings indicate that extracts from rabbit skin inflamed by the vaccinia virus can attenuate neurotoxicity induced by intrathecal injection of bupivacaine in pregnant rats, possibly by inhibiting caspase-9 protein expression and suppressing nerve cell apoptosis.

关键词： neural regeneration peripheral nerve injury vaccinia virus extract bupivacaine neurotoxicity caspase-9 apoptosis local anesthetic grants-supported paper neuroregeneration

Optimization of transport passage with dragline system in thick overburden open pit mine

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International Journal of Mining Science and Technology 2013年第6期23卷 901-906页

作者： Zhang Weishi cai qingxiang Chen Shuzhao School of Mining Engineering China University of Mining&Technology Shenhua Group Zhungeer Energy Co.Ltd. State Key Laboratory of Coal Resources and Mine Safety China University of Mining&Technology

According to the characteristics of opencast coal resources and dragline technology system application in China,the structure and shifting step of transport passage are optimized in this paper.Typical coal transport passage is analyzed in aspects such as the internal dump occupation,dragline operation efficiency,coal transport distance,upper stripping distance and shifting quantities.The middle passage should be given priority in thick overburden open pit mine because the dragline system is only responsible for part stripping task.According to characteristics of middle passage,the transport passage is divided into parallel climbing,vertical climbing and horizontal transport.In addition,the transport passage structure optimization model and shifting distance optimization model are established in this paper.The case study in Heidaigou open pit mine shows that,the parallel climbing height is accounted for about 60%of the total height,and reasonable shifting distances of the first mining area and the second mining area are 240 and 320 m.Sensitivity analysis shows that,the total passage height has important influence on the shifting step,so it is with the stripping height and passage construction cost to the passage structure.

关键词： Open pit mine Dragline Transport passage Middle passage Internal dump

A comparison of the energy consumption and carbon emissions for different modes of transportation in open-cut coal mines

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International Journal of Mining Science and Technology 2015年第2期25卷 261-266页

作者： Liu Fuming cai qingxiang Chen Shuzhao Zhou Wei School of Mines China University of Mining & Technology State Key Laboratory of Coal Resources and Safe Mining China University of Mining & Technology

Transportation accounts for 80% of open-cut coal mine carbon emissions.With regard to the energy consumption and carbon emissions of transportation within an open-cut mine,this paper systematically compared the work and energy consumption of a truck and belt conveyor on a theoretical basis,and constructed a model to calculate the energy consumption of open-cut mine transportation.Life cycle carbon emission factors and power consumption calculation model were established through a Process Analysis–Life Cycle Analysis(PA–LCA).The following results were obtained:(1) the energy consumption of truck transportation was four to twelve times higher than that of the belt conveyor;(2) the CO2 emissions from truck transportation were three to ten times higher than those of the belt conveyor;(3) with the increase in the slope angle for transportation,the ratio of truck to belt conveyor for both energy consumption and carbon emissions gradually decreased;(4) based on 2013 prices in China,the energy cost of transportation using a belt conveyor in open-cut coal mines could save 0.6–2.4 Yuan/(t km) compared to truck transportation.

关键词：二氧化碳排放量能源消耗交通运输煤矿明挖矿用带式输送机生命周期分析卡车运输

3D stability analysis method of concave slope based on the Bishop method

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International Journal of Mining Science and Technology 2017年第2期27卷 365-370页

作者： Zhang Tianwen cai qingxiang Han Liu Shu Jisen Zhou Wei School of Mines China University of Mining and TechnologyXuzhou 221116China Xiaolongtan Mining Administration Kaiyuan 661699China

In order to study the stability control mechanism of a concave slope with circular landslide, and remove the influence of differences in shape on slope stability, the limit analysis method of a simplified Bishop method was employed. The sliding body was divided into strips in a three-dimensional model, and the lateral earth pressure was put into mechanical analysis and the three-dimensional stability analysis methods applicable for circular sliding in concave slope were deduced. Based on geometric structure and the geological parameters of a concave slope, the influence rule of curvature radius and the top and bottom arch height on the concave slope stability were analyzed. The results show that the stability coefficient decreases after growth, first in the transition stage of slope shape from flat to concave, and it has been confirmed that there is a best size to make the slope stability factor reach a maximum. By contrast with average slope, the stability of a concave slope features a smaller range of ascension with slope height increase, which indicates that the enhancing effect of a concave slope is apparent only with lower slope heights.

关键词：简化Bishop法边坡稳定性稳定分析方法三维模型稳定系数侧向土压力稳定控制极限分析

Distribution of Methyl Mercury in Rana chensinensis and Environmental Media in Gold-mining Areas of Upper Reaches of Songhua River,China

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Chinese Geographical Science 2010年第4期20卷 330-336页

作者： WANG Ning ZHANG Gang LIU Te cai qingxiang College of Urban and Environment Sciences Northeast Normal University Changchun 130024 China

The distribution characteristics of methyl mercury in Rana chensinensis and water,sediment and soil in gold-mining areas of the upper reaches of the Songhua River,China were studied by field sampling and laboratory testing.The results show that the methyl mercury contents in water,sediment and soil in gold-mining areas are much higher than those in the control site,indicating that gold-mining activities intensify the methyl mercury pollution in the study area.Methyl mercury contents are in a descending order of sediment > soil > water in the environment,and in a descending order of brain > viscera > muscle > skin in Rana chensinensis.There are significant correlation between methyl mercury contents in Rana chensinensis and those in water and sediment.In particular,the methyl mercury content in the skin of Rana chensinensis is positively correlated with those in water and sediment in spring.Therefore,skin is one of main intake pathways for methyl mercury due to its high permeability.

关键词：松花江开采区林蛙环境介质上游中国汞分布金矿

Mechanical properties of material in a mine dump at the Shengli#1 Surface Coal Mine,China

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International Journal of Mining Science and Technology 2017年第3期27卷 545-550页

作者： Gao Shiyou Zhou Wei Shi Xuyang cai qingxiang Crusoe Garmondyu E.Jr. Jisen Shu Huang Yuejun School of Mines China University of Mining&TechnologyXuzhou 221116China Shenhua Beidian Shengli Energy Co.Ltd. Xilinhaote 026000China

In-situ experiments were conducted to investigate the mechanical properties of the soil-rock mixture in the internal dump of the Shengli #1 Surface Coal Mine, China. Based on the experimental results, this study used comparative analysis and found that the shear strength of the soil-rock mixture in the dump was greater than the residual shear strength of the original rock. The results showed that the material presented in the dump as large blocks was the main factor affecting the strength of the soil-rock mixture.Numerical simulation was carried out for the analyses of three factors: different combinations of shear failure, rolling failure along with different large-block radius ratios, and mixture densities. The results illustrated that the cohesion and angle of internal friction of the soil-rock mixture are 12 kPa and 32.26°. However, in some cases the bench angle in the dump was controlled by a coupling relationship of rocks in the material. Finally, the stability of a soil slope showed a linear relationship with the large-block radius ratio and the bulk density.

关键词： Surface coal mine Soil-rock mixture Residual strength In-situ experiment Mechanical model

Zonal extraction technology and numerical simulation analysis in open pit coal mine

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International Journal of Mining Science and Technology 2012年第4期22卷 487-491页

作者： Chen Yanlong cai qingxiang Shang Tao Peng Hongge Zhou Wei Chen Shuzhao School of Mines China University of Mining&TechnologyXuzhou 221116China Department of Earth Resources Engineering Faculty of EngineeringKyushu UniversityFukuoka 819-0395Japan

In order to enhance coal recovery ratio of open pit coal mines,a new extraction method called zonal mining system for residual coal around the end-walls is presented.The mining system can improve economic benefits by exploiting haulage and ventilation roadways from the exposed position of coal seams by utilizing the existing transportation systems.Moreover,the main mining parameters have also been discussed.The outcome shows that the load on coal seam roof is about 0.307 MPa and the drop step of the coal seam roof about 20.3 m when the thickness of cover and average volume weight are about 120 m and 0.023 MN/m 3 respectively.With the increase of mining height and width,the coal recovery ratio can be improved.However,when recovery ratio is more than 0.85,the average stress on the coal pillar will increase tempestuously,so the recovery ratio should also be controlled to make the coal seam roof safe.Based on the numerical simulation results,it is concluded that the ratio of coal pillar width to height should be more than 1.0 to make sure the coal pillars are steady,and there are only minor displacements on the end-walls.

关键词：数值模拟分析露天煤矿提取技术煤层顶板分区平均体重煤柱应力煤柱宽度

Calculation of slope-cover height under price fluctuation in open-pit mines

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International Journal of Mining Science and Technology 2014年第3期24卷 293-297页

作者： Ma Jinyan cai qingxiang Liu Fuming Chen Shuzhao School of Mines China University of Mining and Technology State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology China Coal Import and Export Corporation

Leaving ditches between adjacent mining areas can effectively reduce re-stripping in the latter mining area and simultaneously lead to an increment in internal dumping costs in the former mining area. This paper establishes calculation models for these two marginal costs. The optimizing model for slope cover height can be determined by including marginal cost models in the objective function. The paper has two main contributions:(a) it fully considers redistribution of dumping space in the model;(b) it introduces price fluctuations and cash discounts in the model. We use the typical open-pit mine as an example to test and prove the model. We conclude that a completely covered slope is reasonable in Haerwusu open pit mine; in addition to an increasing price index, the slope cover height can be reduced; and that price changes are one of the most important influencing factors of slope cover height optimization in an open-pit mine.

关键词：计算模型价格波动完全覆盖露天矿边坡边际成本优化模型目标函数

A　Proposed　Program　for　Technological　Development　of　Opencast　Mining　in　China

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China Coal 1996年第1期 27-31页

作者： Zhang Youdi cai qingxiang et al.

ＡＰｒｏｐｏｓｅｄＰｒｏｇｒａｍｆｏｒＴｅｃｈｎｏｌｏｇｉｃａｌＤｅｖｅｌｏｐｍｅｎｔｏｆＯｐｅｎｃａｓｔＭｉｎｉｎｇｉｎＣｈｉｎａ￥ＺｈａｎｇＹｏｕｄｉ；ＣａｉＱｉｎｇｘｉａｎｇｅｔａｌ．１．Ｔｅｃｈｎｏｌｏｇｉｃ... 详细信息

ＡＰｒｏｐｏｓｅｄＰｒｏｇｒａｍｆｏｒＴｅｃｈｎｏｌｏｇｉｃａｌＤｅｖｅｌｏｐｍｅｎｔｏｆＯｐｅｎｃａｓｔＭｉｎｉｎｇｉｎＣｈｉｎａ￥ＺｈａｎｇＹｏｕｄｉ；ＣａｉＱｉｎｇｘｉａｎｇｅｔａｌ．１．Ｔｅｃｈｎｏｌｏｇｉｃａｌｒｅｓｅａｒｃｈｏｎｏｐｅｎｃ...

关键词： Program