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Chinese Chemical Letters 2018年第9期29卷 1363-1366页

作者： Genhua Xiao Hao Min zhilei zheng Guobo Deng Yun Liang National & Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research Ministry of Education Key Laboratory of the Assembly and Application of Organic Functional Molecules College of Chemistry and Chemical Engineering Hunan Normal University

In this work, an efficient copper-catalyzed three-component reaction for the synthesis of sulfenylimidazo [1,2-a]pyridines using elemental sulfur as the sulfenylating agents has been developed. The reaction could proceed smoothly with a high degree of functional group tolerance and provide the desired products in moderate to good yield.

关键词： Copper Three-component Pyridine Sulfur Arylboronic acids

Investigation into co-pyrolysis characteristics of oil shale and coal

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International Journal of Mining Science and Technology 2012年第2期22卷 245-249页

作者： Miao Zhenyong Wu Guoguang Li Ping Meng Xianliang zheng zhilei School of Chemical Engineering and Technology China University of Mining&TechnologyXuzhou 221116China Key Laboratory of Coal Processing and Efficient Utilization Ministry of EducationXuzhou 221116China Jiangsu CUMT Dazheng Surface Engineering Technology Co.Ltd. Xuzhou 221116China

Samples of five types of coal and oil shale from the Daqing region have been subjected to co-pyrolysis in different blending ratios with thermo-gravimetry （TG）, given a heating rate of 30 ℃/min to a final tem- perature of 900 ℃. Investigations on pyrolysis of mixing coal and oil shale in different proportions were carried out, indicating that the main scope of weight loss corresponding to hydrocarbon oil and gas release was between 350 and 550 ℃. At higher temperatures, significant weight loss was attributed to coke decomposition. Characteristic pyrolysis parameters of blends from oil shale and the high ranked XZ coal varied with the blending ratio, but oil shale dominated the process. At the same blending propor- tions, highly volatile medium and low ranked coal of low moisture and ash content reacted well during pyrolysis and could easily create synergies with oil shale. Medium and high ranked coal with high mois- ture content played a negative role in co-pyrolysis.

关键词： Oil shaleCo-pyrolysisBlending coal samplesBlending ratio

基于有限时间状态观测器的永磁同步直线电机递归终端滑模控制

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中国电机工程学报 2024年第2期44卷 755-765,I0027页

作者：王立俊赵吉文盘真保于子翔郑智磊合肥工业大学电气与自动化工程学院安徽省合肥市230009

针对载荷变化、非线性摩擦、推力波动和外部扰动等不确定性降低永磁同步直线电机位置跟踪性能的问题,提出一种基于有限时间状态观测器的递归终端滑模控制方法。首先,建立考虑有界集总不确定性的直线电机动力学模型。其次,设计快速终端... 详细信息

针对载荷变化、非线性摩擦、推力波动和外部扰动等不确定性降低永磁同步直线电机位置跟踪性能的问题,提出一种基于有限时间状态观测器的递归终端滑模控制方法。首先,建立考虑有界集总不确定性的直线电机动力学模型。其次,设计快速终端滑模函数和积分滑模函数的递归结构,强制系统直接从滑模面启动,减少了跟踪误差的收敛时间。然后,引入有限时间状态观测器实时估计集总不确定性并前馈补偿到控制率中,提高系统的鲁棒性和减少抖振。接着,利用李雅普诺夫理论分析闭环控制器的稳定性和有限时间收敛性。最后,搭建基于半实物AD5435的实验平台,实验结果验证了所提方法的可行性和优越性。

关键词：永磁同步直线电机位置跟踪终端滑模鲁棒性有限时间状态观测器李雅普诺夫

维普期刊数据库博看期刊

煤直接液化残渣催化热解过程中官能团演变特性研究

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当代化工 2024年第9期53卷 2078-2083页

作者：王思琼王云飞郑志磊任耀楠鄂尔多斯应用技术学院化学工程系内蒙古鄂尔多斯017000

采用原位红外催化反应装置,利用傅里叶变换红外光谱仪(FT-IR),以CaCl_(2)·6H_(2)O、FeCl_(3)·6H_(2)O和Cs_(2)SO_(4)为催化剂,对比分析了添加3种不同催化剂以及不同含量的Fe^(3+)在煤直接液化残渣(DCLR)催化热解过程中官能团的演变特... 详细信息

采用原位红外催化反应装置,利用傅里叶变换红外光谱仪(FT-IR),以CaCl_(2)·6H_(2)O、FeCl_(3)·6H_(2)O和Cs_(2)SO_(4)为催化剂,对比分析了添加3种不同催化剂以及不同含量的Fe^(3+)在煤直接液化残渣(DCLR)催化热解过程中官能团的演变特性。结果表明:3种催化剂一定程度上都促进了DCLR的缩聚反应;对于以FeCl_(3)·6H_(2)O为催化剂的样品,当热解温度为500℃左右时苯骨架结构峰位由1546 cm^(-1)向1600 cm^(-1)偏移,表明DCLR内的缩聚反应大于分解反应,其芳香骨架结构缩聚程度提高,稠环体系变大;对比不同浓度FeCl_(3)·6H_(2)O在升温过程中对脂肪侧链甲基和亚甲基在热解过程中的催化效果,发现Fe^(3+)在DCLR热解过程中对脂肪族甲基的脱除起到了抑制作用,且随着样品中Fe^(3+)含量的增加(在质量分数为1%~10%时),其抑制作用越强。

关键词：煤直接液化残渣催化热解官能团演变

部分脱灰及碱金属对煤直接液化渣热化学过程的影响

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广东化工 2024年第16期51卷 13-16页

作者：郑志磊王云飞鞠丽颖侯丽华庞颖哲杨晓亭鄂尔多斯应用技术学院内蒙古鄂尔多斯017000

以煤直接液化渣为原料,利用热重分析仪,考察了部分脱灰和碱金属对其在水蒸气气氛下热化学过程的影响,并计算了气化阶段的表观活化能。结果表明:部分脱灰提高了煤直接液化渣在热解和气化阶段的转化率,降低了半焦的表观活化能,对热化学过... 详细信息

以煤直接液化渣为原料,利用热重分析仪,考察了部分脱灰和碱金属对其在水蒸气气氛下热化学过程的影响,并计算了气化阶段的表观活化能。结果表明:部分脱灰提高了煤直接液化渣在热解和气化阶段的转化率,降低了半焦的表观活化能,对热化学过程产生积极的影响;NaCl在热解和气化过程中均未表现出明显的催化作用;KCl在热解过程中同样没有表现出明显的催化作用,在气化阶段,则提高了半焦在低温下的气化转化率,表现出了催化作用,并使半焦的气化反应进入到了内扩散过渡区。

关键词：煤直接液化渣部分脱灰碱金属热化学过程动力学

新《世界反兴奋剂条例》下涉特定物质违纪处罚研究

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武汉体育学院学报 2016年第11期50卷 42-48页

作者：郑志磊姜世波山东大学体育教学部山东威海264209 山东大学体育法学研究中心山东威海264209 山东大学法学院山东威海264209

涉特定物质案件是争议最多的一类兴奋剂案件。在本次《世界反兴奋剂条例》修订之前,在涉特定物质违纪案件中,就体育界对社会毒品的管制强度问题、"提高比赛成绩的意图"的证明问题、过错程度的划分等问题就存在着很大的争议。2015年版《... 详细信息

涉特定物质案件是争议最多的一类兴奋剂案件。在本次《世界反兴奋剂条例》修订之前,在涉特定物质违纪案件中,就体育界对社会毒品的管制强度问题、"提高比赛成绩的意图"的证明问题、过错程度的划分等问题就存在着很大的争议。2015年版《世界反兴奋剂条例》对这些问题都做出了回应,对规则进行了大幅度的调整,但仍存在着社会毒品政策不统一、"提高比赛成绩的意图"问题难以回避、过错程度的分类仍待调整、主观故意的证明、涉仅赛内禁用的特定物质案件中故意的认定等问题,有待继续研究。

关键词：世界反兴奋剂条例特定物质违纪处罚

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水联网渠道可控性判别指标研究

水力发电学报 2019年第7期38卷 57-66页

作者：郑志磊王忠静清华大学水利水电工程系北京100084 清华大学水沙科学与水利水电工程国家重点实验室北京100084 青海大学省部共建三江源生态与高原农牧业国家重点实验室西宁810016

渠道是调水和输配水的主要工程型式,渠道可控性是渠道水联网控制安全与高效运行的重要前提。本文根据一阶时滞系统的一般可控性原理,提出了基于积分时滞模型参数的渠道可控性概念及其判别指标,建立了渠道可控性与自动控制方法选择的判... 详细信息

渠道是调水和输配水的主要工程型式,渠道可控性是渠道水联网控制安全与高效运行的重要前提。本文根据一阶时滞系统的一般可控性原理,提出了基于积分时滞模型参数的渠道可控性概念及其判别指标,建立了渠道可控性与自动控制方法选择的判别关系。以疏勒河昌马南灌区二分干渠为例,模拟验证了上述可控性指标及算法选择合理性。研究表明,案例渠道可控性指标为0.2~0.3,比例积分算法对此系统无法有效控制,线性二次型算法控制效果受扰动幅度影响较大,而模型预测算法能有效控制。这一结论进一步说明了渠道控制效果是渠道可控性与控制算法的综合结果,可控性判别指标可用于判断渠道可控性并合理选择控制算法以及指导渠道设计。

关键词：水联网渠道自动控制积分时滞模型一阶时滞系统渠道可控性判别指标控制算法

Plate tectonics in the Archean:Observations versus interpretations

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Science China Earth Sciences 2024年第1期67卷 1-30页

作者： YongFei zheng School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China Key Laboratory of Crust-Mantle Materials and Environment Chinese Academy of SciencesHefei 230026China Center of Excellence for Comparative Planetology Chinese Academy of SciencesHefei 230026China

Plate tectonics theory,established in the 1960s,has been successful in explaining many geological phenomena,processes and events that occurred in the ***,the theory has often struggled to provide a coherent framework in interpreting geological records in continental interior and Precambrian *** dealing with the relationship between plate tectonics and continental geology,continental interior tectonics was often separated from continental margin tectonics in the inheritance and development of their structure and *** separation led to the illusion that the plate tectonics theory is not applicable to Precambrian geology,particularly in explaining the fundamental geological characteristics of Archean *** this illusion does not mean that the Archean continental crust did not originate from a regime of plate tectonics,it led to the development of alternative tectonic models,often involving vertical movements under a regime of stagnant lid tectonics,including not only endogenous processes such as gravitational sagduction,mantle plumes and heat pipes but also exogenous processes such as bolide *** vertical processes were not unique to the Archean but persisted into the *** result from mantle poloidal convection at different depths,not specific to any particular *** the plate tectonics theory from the traditional kinematic model in the 20th century to a holistic kinematic-dynamic model in the 21st century and systematically examining the vertical transport of matter and energy at plate margins,it is evident that plate tectonics can explain the common geological characteristics of Archean cratons,such as lithological associations,structural patterns and metamorphic *** deciphering the structure and composition of convergent plate margins as well as their dynamics,the formation and evolution of continental crust since the Archean can be divided into ancient plate tectonics in the Preca

关键词： Plate tectonics Archean geology Continental origin Crustal reworking Plate interior Plate margin

Discovery of the Significant Impacts of Swell Propagation on Global Wave Climate Change

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Journal of Ocean University of China 2024年第3期23卷 594-604页

作者： zheng Chongwei Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China

This study compared the differences in the wave climate in the South China Sea and North Indian Ocean under these two datasets:ERA-40 wave reanalysis and Mei’s hindcast wave *** the numerical calculation of regional ocean waves,the wave climate characteristics exhibited significant bias if the influence of external swells(swells from afar)was not fully considered,which may provide an incorrect basis for global climate change analysis.1)The trends of the significant wave height(SWH)obtained from the two datasets showed significant differences,such as those of the Bay of Bengal and the Java Sea in *** the past 45 years,SWH from ERA-40(SWH-ERA)exhibited a significant annual increase in low-latitude waters of the North Indian Ocean(0.2-0.6 cm yr^(-1))and South China Sea(0.2-0.8 cm yr^(-1)).2)In the Bay of Bengal,the SWH-ERA in each month was generally 0.5 m higher than the SWH from Mei’s hindcast wave data(SWH-Mei)and can reach 1.0 m higher in some months.3)In the Bay of Bengal,SWH-ERA and SWH-Mei increased significantly at annual rates of 0.13 and 0.27 cm yr^(-1),*** increasing trend was mainly reflected after ***-ERA showed a trough in 1975(1.33 m)and a crest in 1992(1.83 m),which were not reflected in SWH-Mei.

关键词： wave climate climatic trend monthly variation annual variation external swell

A positive trend in the stability of global offshore wind energy

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Acta Oceanologica Sinica 2024年第1期43卷 123-134页

作者： Chongwei zheng Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China Shandong Provincial Key Laboratory of Ocean Engineering Ocean University of ChinaQingdao 266100China

The recognition on the trend of wind energy stability is still extremely rare,although it is closely related to acquisition efficiency,grid connection,equipment lifetime,and costs of wind energy *** the 40-year(1979–2018)ERA-Interim data from the European Center for Medium-Range Weather Forecasts,this study presented the spatial-temporal distribution and climatic trend of the stability of global offshore wind energy as well as the abrupt phenomenon of wind energy stability in key regions over the past 40 years with the climatic analysis method and Mann-Kendall(M-K)*** results show the following 5 points.(1)According to the coefficient of variation(C_(v))of the wind power density,there are six permanent stable zones of global offshore wind energy:the southeast and northeast trade wind zones in the Indian,Pacific and Atlantic oceans,the Southern Hemisphere westerly,and a semi-permanent stable zone(North Indian Ocean).(2)There are six lowvalue zones for both seasonal variability index(S_(v))and monthly variability index(M_(v))globally,with a similar spatial distribution as that of the six permanent stable zones.M_(v) and S_(v) in the Arabian Sea are the highest in the world.(3)After C_(v),M_(v) and S_(v) are comprehensively considered,the six permanent stable zones have an obvious advantage in the stability of wind energy over other sea areas,with C_(v) below 0.8,M_(v) within 1.0,and S_(v) within 0.7 all the year round.(4)The global stability of offshore wind energy shows a positive climatic trend for the past four decades.C_(v),M_(v) and S_(v) have not changed significantly or decreased in most of the global ocean during 1979 *** is,wind energy is flat or more stable,while the monthly and seasonal variabilities tend to shrink/smooth,which is beneficial for wind energy utilization.(5)C_(v) in the low-latitude Pacific and M_(v) and S_(v) in both the North Indian Ocean and the low-latitude Pacific have an obvious abrupt phenomenon at the end of

关键词： global oceans wind energy stability spatial-temporal distribution climatic trend