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Molecular structure characterization of middle-high rank coal via^(13)C NMR,XPS,and FTIR spectroscopy

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China Geology 2024年第4期7卷 702-713页

作者： xiao-ming ni Jing-shuo Zhang xiao-kai Xu Bao-yu Wang School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China Institute of Resources&Environment Henan Polytechnic UniversityJiaozuo 454000China

Elemental analysis,nuclear magnetic resonance carbon spectroscopy(^(13)C-NMR),X-ray photoelectron spectroscopy(XPS)and Fourier transform infrared spectroscopy(FTIR)experiments were carried out to determine the existence of aromatic structure,heteroatom structure and fat structure in ***(materials studio)software was used to optimize and construct a 3D molecular structure model of coal.A method for establishing a coal molecular structure model was formed,which was“determination of key structures in coal,construction of planar molecular structure model,and optimization of three-dimensional molecular structure model”.The structural differences were compared and *** results show that with the increase of coal rank,the dehydrogenation of cycloalkanes in coal is continuously enhanced,and the content of heteroatoms in the aromatic ring *** heteroatoms and branch chains in the coal are reduced,and the structure is more orderly and *** stability of the structure is determined by theπ-πinteraction between the aromatic rings in the nonbonding energy *** Stretching Energy The size of EB determines how tight the structure *** research results provide a method and reference for the study of the molecular structure of medium and high coal ranks.

关键词： Molecular structure model Carbon-13 nuclear magnetic resonance(NMR) X-ray photoelectron spectroscopy(XPS) Fourier transform infrared spectroscopy(FTIR) Coal

Coal matrix deformation characteristics in the process of carbon dioxide displacing different gas saturation coal-bed methane

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Journal of Coal Science & Engineering(China) 2013年第3期19卷 303-308页

作者： xiao-ming ni Quan-Zhong LI Yan-Bin WANG Sha-Sha GAO School of Energy Science and Engineering Henan Polytechnic University Jiaozuo 454000 China State Key Laboratory Cultivation Base for Gas Geology and Gas Control Henan Polytechnic University Jiaozuo 454000 China College of Geo-science and Surveying Engineering China University of Mining & Technology (Beijing) Beijing 100083 China

It is fundamental that changes in coal reservoir permeability are researched, in particular, the accurate determination of variations in the coal matrix caused by CO2 replacing CH4 at different gas saturation conditions. Based on the surface free energy, the extended Langmuir isothermal adsorption model, combined with CO2 replacing CH4 in experimental trials, and calling on the more general principles and characteristics of the field, mathematical models describing the coal matrix as it undergoes different processes such as CO2 injection and desorption were established. Combined with laboratory data about CO2 replacement under different methane saturation conditions, a law governing the variations in coal matrix CO2 replacement under different methane gas saturation conditions was obtained. The results showed that： in the injection process, the coal matrix expansion rate caused by CO2 or CH4 was exponentially increased with the CO2 pressure increase, the expansion caused by CO2 was far greater than the expansion caused by CH4 in the desorption process, the coal matrix shrinkage caused by CO2 or CH4 was exponentially increased with the pressure decrease, the shrinkage caused by CO2 was larger than the shrinkage caused by CH4 under the same pressure and different gas saturation, the total shrinkage in the desorption process in the coal matrix was greater than the total expansion in the injection process. At higher gas saturations, the total coal matrix shrinkage volume exceeded the total expansion corresponding to pressure points higher in the desorption process.

关键词： carbon dioxide coal matrix adsorption swelling desorption contraction

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我国人为源挥发性有机物反应性排放清单

环境科学 2017年第3期38卷 845-854页

作者：梁小明张嘉妮陈小方石田立孙西勃范丽雅叶代启华南理工大学环境与能源学院广州510006 广东省大气环境与污染控制重点实验室广州510006 大气污染控制广东高校工程技术研究中心广州510006

以我国人为源挥发性有机物(VOCs)为研究对象,使用具有代表性的VOCs总量排放清单、各污染源成分谱及物种最大增量反应活性值(MIR),建立了2010年我国人为源VOCs基于臭氧生成潜势(OFP)的反应性排放清单.结果表明,2010年我国人为源挥发性有... 详细信息

以我国人为源挥发性有机物(VOCs)为研究对象,使用具有代表性的VOCs总量排放清单、各污染源成分谱及物种最大增量反应活性值(MIR),建立了2010年我国人为源VOCs基于臭氧生成潜势(OFP)的反应性排放清单.结果表明,2010年我国人为源挥发性有机物总OFP为84 187.61 kt,其中,烷烃6 882.53 kt,烯炔烃41 496.92 kt,芳香烃32 945.32 kt,卤代烃161.45kt,含氧有机化合物2 701.40 ***贡献前10种物种分别为丙烯、乙烯、间/对-二甲苯、甲苯、1-丁烯、邻-二甲苯、1,2,4-三甲苯、1,3-丁二烯、间-乙基甲苯和乙苯,占人为源总OFP的63.95%,仅占VOCs排放总量的31.84%.人为源三大污染源中,工业源贡献了49.29%的OFP,为最大贡献源,其次是交通源28.31%和农业源22.40%.建筑装饰、石油炼制、储存与运输、机械设备制造、交通设备制造和包装印刷为工业OFP主要贡献源;轻型载客汽车、重型载客汽车及摩托车为交通源OFP污染控制的重点;生物质燃烧两类子源均为农业源OFP重点控制对象.山东、江苏、广东、浙江和河南是我国人为源OFP贡献最大的省份,占人为源总OFP的39.65%.该反应性清单的建立,对我国基于反应性臭氧(O3)控制对策的制定具有重要意义.

关键词： VOCs 物种排放清单臭氧生成潜势人为源中国

The golden age for popularizing big data

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Science China(Information Sciences) 2016年第10期59卷 239-241页

作者： Lionel ming-shuan ni Jiang xiao Haoyu TAN Department of Computer and Information Science the University of Macau Department of Computer Science and Engineering Hong Kong University of Science and Technology

The fast development of the Internet and Mobile Internet has opened up the era of big *** academia and industry have realized that the potential knowledge hidden in big data is huge and great business opportunities can be created by exploiting the data deeply and *** in 2000,as legacy RDBMS[1]could no longer meet the requirements of handling large volumes of data,new technologies that can provide efficient query and fast processing of big data were in urgent need.A big data technology pioneer,Google,

关键词： RDBMS The golden age for popularizing big data SQL

甾体不对称合成的研究 Ⅸ.直链1,5-羟酮化合物经由氧化铝引起的手性转移

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化学学报 1984年第7期42卷 706-709页

作者：周维善周小鸣倪元中国科学院上海有机化学研究所中国科学院上海有机化学研究所

周维善等曾报道从微生物不对称还原所得（+）-（1S,2R）-单环1,5-羟酮化合物1的苯溶液,用氧化铝柱层析纯化得到了另一个（+）-（3’R）-单环1,5-羟酮化合物2.它们仅在羟基和酮基的位置不同,可能是由于与Al2O3形成六员环过渡态（A）而... 详细信息

周维善等曾报道从微生物不对称还原所得（+）-（1S,2R）-单环1,5-羟酮化合物1的苯溶液,用氧化铝柱层析纯化得到了另一个（+）-（3’R）-单环1,5-羟酮化合物2.它们仅在羟基和酮基的位置不同,可能是由于与Al2O3形成六员环过渡态（A）而发生分子内的负氢离子转移,即分子内的氧化还原啪,从而引起了手性转移.因为羟酮处于1,5-位置,故也可称其为1,5-手性转移.以后我们又用与1结构类似的单环1,5-羟酮化合物3,也得到相同的结

关键词：不对称合成柱层析纯化负氢离子过渡态半缩酮酮基氧化还原癸酸周维核磁共振谱

Application of Holdridge life-zone model based on the terrain factor in Xinjiang Automous Region

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Journal of Environmental Sciences 2005年第6期17卷 1042-1046页

作者： ni Yong-ming OUYANG Zhi-yun WANG xiao-ke Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

This study improved the application of the Holdridge life-zone model to simulate the distribution of desert vegetation in China which gives statistics to support eco-recovery and ecosystem reconstruction in desert area. This study classified the desert vegetation into four types：（1） LAD： little arbor desert; （2） SD： shrub desert：（3） HLHSD： half-shrub, little half-shrub desert; （4） LHSCD： little halfshrub cushion desert. Based on the classification of Xinjiang desert vegetation, the classical Holdridge life-zone model was used to simulate Xinjiang desert vegetation＇s distribution and compare the Kappa coefficient result of the model with table of accuracy represented by Kappa values. The Kappa value of the model was only 0.19, it means the simulation result was poor. To improve the life-zone model application to Xinjiang desert vegetation type, a set of plot standards for terrain factors was developed by using the plot standard as the reclassification criterion to climate sub-regime. Then the desert vegetation in Xinjiang was simulated. The average Kappa value of the second simulation to the respective climate regime was 0.45. The Kappa value of final modeling result was 0.64, which is the better value. The modification of the model made it in more application region. In the end, the model＇ s ecological relevance to the Xinjiang desert vegetation types was studied.

关键词： Xinjiang desert vegetation types Holdridge life-zone terrain climate regime

基于STM32的步进电机离散化S形曲线加减速控制方法

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自动化与仪表 2017年第6期32卷 57-61页

作者：周团坤张莹杨晓明张尼沈坤西安西北有色地质研究院有限公司西安710054

步进电机是一种将脉冲信号转换为相应角位移的执行元件,具有控制简单、无累计误差等优点,广泛应用于工业控制领域。然而步进电机直接以较高速度启动或者停止时,由于电机的惯性原因,可能会发生失步或者过冲,解决失步或过冲是步进电机定... 详细信息

步进电机是一种将脉冲信号转换为相应角位移的执行元件,具有控制简单、无累计误差等优点,广泛应用于工业控制领域。然而步进电机直接以较高速度启动或者停止时,由于电机的惯性原因,可能会发生失步或者过冲,解决失步或过冲是步进电机定位控制的关键。该文基于对STM32的研究,提出了一种离散化的S形曲线加减速控制方法,很好地实现了对步进电机的加减速精确控制。采用S形曲线加减速控制可以很好地解决失步或过冲这类问题。

关键词：步进电机加/减速控制 S形曲线离散化单片机STM32

Performance analysis of the mooring system of a two-module scientific research and demonstration platform

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Journal of Hydrodynamics 2021年第5期33卷 901-914页

作者： Xin-yun ni xiao-ming Cheng Bo Wu Jun Ding Yong-lin Ye Ze Sun China Ship Scientific Research Center Wuxi 214082China

A mooring system has been designed for the position keeping of a two-module semi-submersible platform which is connected by hinge-type *** the excitation of ocean waves,the relative motion between the two modules can be *** is therefore no longer adequate to model the platform as a single rigid body in the analysis of the performance of the mooring *** this study,an analysis method has been developed based on the three-dimensional frequency domain hydroelasticity theory in conjunction with the time domain quasi-static analysis method of mooring actions,which takes into account of the coupling effect of the platform motion and mooring *** proposed method is verified by comparing the numerical results with the measured data obtained from the on-site *** comparison shows a good agreement,and demonstrates the feasibility and effectiveness of the proposed method for the analysis of the module responses and mooring tensions of multi-module floating platforms.

关键词： Mooring system coupled analysis sea trial verification two-module floating platform hydroelasticity theory numerical comparison

Fluidized-bed pyrolysis of waste bamboo

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1495-1499页

作者： xiao Gang ni ming-jiang HUANG He CHI Yong xiao Rui ZHONG Zhao-ping CEN Ke-fa Key Lab. on Clean Coal Power Generation and Combustion Technology of Ministry of Education School of Energ3＂ and Environment Southeast University Nanjing 210096. China State Key Lab. of Clean Energy Utilization College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China College of Lfe Science and Pharmaceutical Engineering Nanjing University of Technology Nanjing 210009 China

Bamboo was a popular material substituting for wood, especially for one-off commodity in China. In order to recover energy and materials from waste bamboo, the basic characteristics of bamboo pyrolysis were studied by a thermogravimetric analyzer. It implied that the reaction began at 190-210℃, and the percentage of solid product deceased from about 25% to 17% when temperature ranged from 400℃ to 700℃. A lab-scale fluidized-bed furnace was setup to research the detailed properties of gaseous, liquid and solid products respectively. When temperature increased from 400℃ to 700℃, the mass percent of solid product decreased from 27% to 17% approximately, while that of syngas rose up from 19% to 35%. When temperature was about 500℃, the percentage of tar reached the top, about 31%. The mass balance of these experiments was about 93%-95%. It indicated that three reactions involved in the process： pyrolysis of exterior bamboo, pyrolysis of interior bamboo and secondary pyrolysis of heavy tar.

关键词： Bamboo Pyrolysis Fluidized beds Syngas Tar