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Characteristics of Gas Emission at Super-Length Fully-Mechanized Top Coal Caving Face

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Journal of China University of Mining and Technology 2007年第4期17卷 447-452页

作者： xu jia-lin YU Bei-jian LOU Jin-fu WANG Dong-ping State Key Laboratory of Coal Resource and Mine Safety Xuzhou Jiangsu 221008 China School of Mineral and Safety Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China Yangquan Coal Group Yangquan Shanxi 045008 China

Characteristics of gas emission at the K8206 working face in the Third mine of the Yangquan Coal Group were investigated. The effects of strata movement,advancing velocity of working face,production capacity of working face and gas extraction capability of strike high-level entry on gas emission at K8206 working face were analyzed. A regression equation,reflecting the relationship between relative gas emission rate and the production capacity of work-ing faces,was established. Another regression equation showing the relationship between the gas emission rate from adjacent layers when the working face was advancing for one metre and advancing velocity was derived. It can be con-cluded that,1) the amount of gas emitted at the K8206 working face is far greater than that of ordinary top coal caving faces with a dip length of 180-190 m; 2) the dynamic process of gas emission from adjacent layers during the initial mining stage is controlled by the movement of key strata; 3) the amount of gas emitted that needs to be forced out by air is greatly affected by the capability of gas extraction; 4) when the advancing velocity is between 3.5-5.5 m/d or when the output is up to 8-12 kt/d,the gas emission from adjacent layers is almost constant.

关键词： super-length fully-mechanized top coal caving face characteristics of gas emission strata movement

Phase noise sensitivity analysis of lattice constellation

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The Journal of China Universities of Posts and Telecommunications 2010年第2期17卷 36-40页

作者： YU Guang-wei NIU Kai HE Zhi-qiang WANG xu-zhen lin jia-ru Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

Based on the assumption of large number of constellation points and high signal-to-noise ratio （SNR）, phase noise sensitivity of lattice constellation is analyzed. The upper bound of symbol error rate （SER） in additive white Gaussian noise （AWGN） channel is derived from pairwise error probability. For small phase noise, phase noise channel is transformed to AWGN channel. With the aid of Wiener model, the obtained upper bound can be extended to phase noise channel. The proposed upper bound can be used as performance criterion to analyze the sensitivity of phase noise in multi-dimensional lattice constellation. Simulation results show that with the same normalized spectral efficiency, higher dimensional lattice constellations are more sensitive than lower ones in phase noise channel. It is also shown that with the same dimension of constellation, larger normalized spectral efficiency means more performance loss in phase noise channel.

关键词： lattice constellation symbol error rate (SER) phase noise

A High Power Single Frequency Diode Side-Pumped Nd:YAG Ring Laser

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Chinese Physics Letters 2011年第8期28卷 122-125页

作者： XIE Shi-Yong BO Yong xu jia-lin WANG Zhi-Chao PENG Qin-Jun CUI Da-Fu xu Zu-Yan RCLPT Key Lab of Functional Crystal and Laser TechnologyTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 Laboratory of Optical Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190 Graduate School of the Chinese Academy of Sciences Beijing 100190

We demonstrate a high-power single-frequency diode-side pumped Nd:YAG laser at 1064 nm.A bow-tie ring cavity configuration comprising two plane and two curved mirrors with two-rod birefringence compensation is *** influence of length Lx between two curved mirrors on output power and beam quality is investigated theoretically and experimentally while the separation of the flat mirrors is set to be 656 mm and the fold angle is 10°.When the pump powers are 358,343 and 329 W at 808 nm,the maximal output powers of 31.9,26 and 14.1 W are obtained with beam quality factors M2=1.41,1.12 and 1.20 for Lx=205,215 and 230 mm,respectively.

关键词： Nd:YAG pumped pump

A 171.4 W Diode-Side-Pumped Q-Switched 2 μm Tm:YAG Laser with a 10 kHz Repetition Rate

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Chinese Physics Letters 2012年第4期29卷 104-107页

作者： CAO Dong DU Shi-Feng PENG Qin-Jun BO Yong xu jia-lin GUO Ya-Ding ZHANG Jing-Yuan CUI Da-Fu xu Zu-Yan RCLPT Key Lab of Functional Crystal and Laser TechnologyTechnical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190 Graduate University of the Chinese Academy of Sciences Beijing 100190

A 785 nm diode-side-pumped high-power high-pulse-repetition-frequency Q-switched 2 μm Tm:YAG laser system is *** a pump power of 1300 W,a 171.4 W average output power is achieved at a pulse repetition frequency of 10 *** our knowledge,this is the highest average output power for a diode-pumped all solid-state Q-switched 2 μm Tm:YAG *** laser output corresponds to an optical-to-optical conversion efficiency of 13.3% and a slope efficiency of 18.9%.

关键词： pumped switched power

Brnsted Acidic Ionic Liquids: Efficient and Recyclable Catalytic Systems for Beckmann Rearrangement

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Chemical Research in Chinese Universities 2011年第6期27卷 973-976页

作者： WU Mao-cheng DUAN Hai-feng CAO Jun-gang LIANG Da-peng jiaNG Feng GAO Han jia xu-dong lin Ying-jie College of Chemistry Jilin University Changchun 130012 P. R. China

Six Brnsted acidic ionic liquids（ILs） 1a―1f were synthesized and used as the dual solvent-catalyst systems for Beckmann rearrangement reactions. Among ILs 1a―1f, IL 1a exhibited the highest catalytic activity and successfully catalyzed the Beckmann rearrangement of ketoximes, and the corresponding amides were obtained in good to excellent yields（74%―92%）. In addition, IL 1a could be recovered easily and reused at least three times without any loss of catalytic activity.

关键词： Brnsted acidic ionic liquid Beckmann rearrangement Oxime

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浅埋近距离煤层出煤柱开采压架防治对策

采矿与安全工程学报 2013年第3期30卷 323-330页

作者：鞠金峰许家林中国矿业大学煤炭资源与安全开采国家重点实验室矿业工程学院江苏徐州221116

针对浅埋近距离煤层工作面在推出上覆遗留煤柱过程中普遍出现的压架灾害,采用理论分析和模拟实验,结合压架发生的机理,提出了相应的防治对策。结果表明:出煤柱开采时,煤柱上方2关键块体形成的三铰式结构是不稳定的,该结构的相对回转运... 详细信息

针对浅埋近距离煤层工作面在推出上覆遗留煤柱过程中普遍出现的压架灾害,采用理论分析和模拟实验,结合压架发生的机理,提出了相应的防治对策。结果表明:出煤柱开采时,煤柱上方2关键块体形成的三铰式结构是不稳定的,该结构的相对回转运动会造成煤层间关键层断裂结构的载荷过大而失稳,最终引起工作面的压架。因此,控制关键块体的回转运动是防治压架的关键。据此提出了以促使关键块体提前回转、阻止和破坏其回转3个方面为思路的压架灾害防治措施,各措施的防治效果得到了相似材料模拟实验的验证,现场应用效果显著。

关键词：浅埋煤层近距离煤层煤柱关键层压架防治

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“政府—企业”节能减排互动机制研究

中国人口·资源与环境 2011年第6期21卷 102-109页

作者：王琳肖序许家林中南大学商学院湖南长沙410083 湖南工业职业技术学院经济管理系湖南长沙410208 中南财经政法大学会计学院湖北武汉430073

我国正处于工业化进程的中后期,能源资源的短缺、环境污染破坏等问题对经济发展的制约日渐显著。企业作为节能减排工作的主要参与者,经常陷入节能减排投入成本高、担负责任大,却经济效益少的现实境地。与之相反,政府则可以在不承担风险... 详细信息

我国正处于工业化进程的中后期,能源资源的短缺、环境污染破坏等问题对经济发展的制约日渐显著。企业作为节能减排工作的主要参与者,经常陷入节能减排投入成本高、担负责任大,却经济效益少的现实境地。与之相反,政府则可以在不承担风险的情况下,享受到企业节能减排所带来的各项收益和资源保存收益,这将影响企业节能减排的积极性。本文构建了一种政府—企业节能减排互动机制激励模型,可求得政府与企业在节能减排战略中最优的责任分摊比例,并依据模型测度出企业节能减排的成本投入和各项经济、环境效益指标,从而为政府合理分摊企业节能减排压力提供科学的依据,并使得企业更有动力实施节能减排战略,最终实现整个社会的帕累托最优。

关键词：能源消耗节能减排互动机制责任分摊