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Law of gas production during coal heating oxidation

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International Journal of Mining Science and Technology 2019年第4期29卷 617-620页

作者： Xianwei Dong zhichao wen Fusheng Wang Yaning Meng School of Mining Engineering North China University of Science and TechnologyTangshan 063210China Key Laboratory of Mining Development and Safety Technology in Hebei Province Tangshan 063210China

Coal spontaneous combustion is a great threat to mine safety,and gas is the key index to describe coal spontaneous combustion.Taking the coal samples of different kinds of coal as research object,the temperature programmed oxidation experiment was carried out,and the gases produced by coal samples at different temperatures were collected and analyzed by gas chromatography.This research studied the variation characteristics of gas species and gas concentrations in different coal samples during heating oxidation.The experimental results show that different coal samples produce different kinds of gases in the process of heating and oxidation.The order of gas production is CO,C2H6,C2H4,C3H8,and the relationship between gas production and temperature is approximately exponential.With the increase of coal metamorphic degree,the turning point temperature of sharp rise in coal sample gas production rate become higher,the oxidation ability of coal sample decreases,and the quantity of gas production decreases during the same time period.

关键词： Heating and oxidation Metamorphic degree of coal Oxidizing ability Gas chromatography

Agriculture green development in China: insights and advances

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 5-19,I0005页

作者： Jianbo SHEN Qichao ZHU Yong HOU wen-Feng CONG wen XU Jiuliang XU zhichao AN Xiaoqiang JIAO Kai ZHANG Tianxiang YU Lin MA Oene OENEMA William J.DAVIES Fusuo ZHANG State Key Laboratory of Nutrient Use and Management College of Resources and Environmental SciencesNational Academy of Agriculture Green DevelopmentChina Agricultural UniversityBeijing 100193China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Wageningen Environmental Research Wageningen University&ResearchWageningen6700 AAthe Netherlands Lancaster Environment Centre University of LancasterLancasterLA14YQUK

Reconciling the tasks of producing adequate amounts of nutritious food for the increasing global population while preserving the environment and natural ecosystems simultaneously is an enormous challenge. The concept of agriculture green development(AGD) and the necessary governmental policies were developed to address the aforementioned challenge in China and to help achieve the related global sustainable development goals. Agriculture green development emphasizes the synergy between green and development;current agriculture has to transform from the intensive farming with high inputs, high environmental impacts and low resource-use efficiency to a more sustainable agriculture, in order to ensure an adequate supply of nutritious food while delivering environmental integrity, improved economic profitability,and social equity. A research program on AGD was established by China Agricultural University with four research themes, namely: green crop production, green integrated crop-animal production, green food and industry,and green ecological environment and ecosystem services, to provide a scientific basis for future developments and to facilitate the implementation of AGD in practice. AGD requires a multistakeholder approach, fueled by innovative and interdisciplinary research. Joint actions have to be taken by governments, farmers, supply industries, consumers, educators, extension services and researchers to support AGD. This requires strong coordination and public awareness campaigns. This review presents the progress that has been made over the past 5 years and makes recommendations for more research and development, in order to better deliver agricultural green and sustainable development on national and international scales.

关键词： Agriculture ecosystem services environmental protection food security green development multi-sectoral cooperation sustainable development

“双碳”目标下我国天然气行业存在的问题及政策建议

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油气田环境保护 2022年第6期32卷 1-5页

作者：温志超国家信息中心

在“双碳”(碳达峰、碳中和)目标导向下,天然气肩负着从化石能源向可再生能源过渡的重要使命。2021年以来天然气消费增速显著,天然气领域体制机制改革不断深化。在“双碳”目标下,当前我国天然气行业面临着上游勘探开采市场仍需进一步放... 详细信息

在“双碳”(碳达峰、碳中和)目标导向下,天然气肩负着从化石能源向可再生能源过渡的重要使命。2021年以来天然气消费增速显著,天然气领域体制机制改革不断深化。在“双碳”目标下,当前我国天然气行业面临着上游勘探开采市场仍需进一步放开,管网运营协调性有待提高,城市燃气储气能力仍需提高,气电发展政策体系仍需健全,市场化的天然气价格机制仍未理顺等问题与挑战。建议完善油气探矿权竞争性出让,加强天然气管网协调管理和储备能力建设,强化气电发展政策支持,完善天然气市场化定价机制,持续推进天然气产供储销体系建设,加快天然气行业高质量发展。

关键词： “双碳” 天然气行业问题产供储销高质量发展

俄乌冲突对全球和我国粮食安全短期影响及建议

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中国物价 2022年第7期 111-114页

作者：温志超国家信息中心经济预测部

随着作为全球重要粮食生产和出口国的俄乌两国冲突不断加剧,粮食短缺的风险日益为各方所关注,联合国粮食及农业组织(FAO)和世界粮食计划署(WFP)相继发出警告称“全球粮食系统受到严重威胁”。本文认为,俄乌冲突极有可能推倒全球粮食危... 详细信息

随着作为全球重要粮食生产和出口国的俄乌两国冲突不断加剧,粮食短缺的风险日益为各方所关注,联合国粮食及农业组织(FAO)和世界粮食计划署(WFP)相继发出警告称“全球粮食系统受到严重威胁”。本文认为,俄乌冲突极有可能推倒全球粮食危机的“多米诺骨牌”,对全球粮食贸易和粮食价格产生剧烈冲击,短期将对一些国家和人群产生巨大影响,但对我国短期影响总体有限且基本可控。我国可采取积极应对的方针,在化解本次粮食危机、维护全球粮食供应链安全中发挥更加重要的作用。

关键词：俄乌冲突粮食危机短期影响

中国产业创新能力评价研究及政策建议——基于我国A股上市公司数据

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中国物价 2022年第12期 46-49页

作者：温志超国家信息中心经济预测部

本文参考熊彼特创新理论与麦肯锡创新理论及相关研究成果,结合我国国情,基于我国A股上市公司数据,从企业创新全链条角度,借助于大数据技术,首次建立了技术创新和模式创新并重的我国产业创新能力评价指标体系。利用构建的评价指标体系从... 详细信息

本文参考熊彼特创新理论与麦肯锡创新理论及相关研究成果,结合我国国情,基于我国A股上市公司数据,从企业创新全链条角度,借助于大数据技术,首次建立了技术创新和模式创新并重的我国产业创新能力评价指标体系。利用构建的评价指标体系从总体创新能力、技术创新能力和模式创新能力三个维度对我国产业创新能力进行了科学评价,并依据评价结果提出相关政策建议,为我国产业转型升级和创新驱动发展提供科学支撑。

关键词：产业创新创新评价上市公司

Genomic surveillance of emerging SARS-CoV-2 Omicron variations in Tianjin Municipality, China 2022

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Biosafety and Health 2024年第2期6卷 61-69页

作者： Xin Gao Ming Zou Yue Lei Zhaolin Tan zhichao Zhuang Baolu Zheng Aiping Yu Yanzhen Han Xiaohui Lu Xiaochang Liu Ying Wang Yuan Wang Liru Guo Guangwen Liu wen Li Yang Liu Likun Lv Peiyong Ning Xiaoyan Li Tianjin Centers for Disease Control and Prevention Tianjin 300011China Tianjin Key Laboratory of Pathogenic Microbiologyof Infectious Disease Tianjin Centers for Disease Controland PreventionTianjin 300011China

The coronavirus disease 2019(COvID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has severely impacted public health.In 2022,the Omicron variant of SARS-CoV-2 rapidly became the dominant circulating variant in the local COVID-19 outbreaks in Tianjin Municipality,China.To gain a deeper understanding of the genetic variations of the Omicron variant in Tianjin,specimens from indi-viduals who tested positive for SARS-CoV-2 between December 2021 and November 2022 were used for virus whole genome sequencing and phylogenetic analysis.A total of 1,674 high-quality Omicron sequences were obtained,consisting of 1,339 sequences from local cases belonging to 20 Phylogenetic Assignment of Named Global Outbreak(PANGO)lineages and 335 sequences from imported cases belonging to 70 lineages.Tianjin experienced five waves of local outbreaks,accompanied by multiple substitutions among subvariants,ranging from the initial BA.1.1 lineage to the subsequent BA.2,BF.7,and BA.5.2 lineages.The evolutionary rate of local strains,estimated to be 28.999 substitutions per year,and the evolutionary rate of imported strains,estimated to be 24.946 substitutions per year,were lower than that of the strains circulating globally.The addi-tional substitutions and deletions of local strains have been used to identify and disrupt the virus transmission chains.The subvariants such as BA.5.2.48,BA.5.2.49,BF.7.14,and XBB.1 circulating in the fifth epidemic wave presented criterial immune escape mutations including S:R346T,S:L452R and S:F486V.It is essential to implement genomic surveillance strategies to investigate further the development of genomic mutation char-acteristics in the SARS-CoV-2 variant.This ongoing monitoring will contribute to a better understanding of the virus's genetic changes and aid in effective control measures.

关键词： Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) Coronavirus disease 2019(COVID-19) Omicron variant Whole genome sequencing(WGS)

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分类政策下北京市生活垃圾管理进展与挑战

环境卫生工程 2023年第5期31卷 99-105页

作者：刘婷婷张前曹婧温志超薛婕北京工业大学循环经济研究院北京100124 北京市燃气集团有限责任公司高压管网分公司北京100010 国家信息中心北京100045 中国环境科学研究院北京100012

通过文献调研、问卷调查以及成本测算的方法,对北京市生活垃圾分类政策的实施效果进行了评估,比较垃圾分类政策实施前后北京市生活垃圾收运处理情况,对北京市生活垃圾的管理现状及存在问题进行了剖析。结果表明:垃圾分类政策的实施促进... 详细信息

通过文献调研、问卷调查以及成本测算的方法,对北京市生活垃圾分类政策的实施效果进行了评估,比较垃圾分类政策实施前后北京市生活垃圾收运处理情况,对北京市生活垃圾的管理现状及存在问题进行了剖析。结果表明:垃圾分类政策的实施促进了垃圾减量化和资源化,提升了居民环保意识;虽然现有生活垃圾处理设施能够匹配当下的处理需求,但随着垃圾分类工作的推进和垃圾处理设施的新建,焚烧企业将出现“吃不饱”的状况,因此需要对垃圾分类和设施建设进行利弊权衡,进一步优化布局并做合理规划。在此基础上,充分考虑北京市垃圾分类政策实施过程中面临的机遇与挑战,从提升分类质量、调整设施建设、创新分类模式、建立协调机制等多方面提出深入推进北京市生活垃圾分类的对策建议,为城市生活垃圾管理规划与政策制定提供了理论基础与现实依据。

关键词：垃圾分类生活垃圾政策作用收运处理

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泥沙异重流稳定水跃的耗能与掺混实验研究

水力发电学报 2023年第9期42卷 11-21页

作者：温志超黄哲徐海珏白玉川张金良黄河勘测规划设计研究院有限公司郑州450003 水利部黄河流域水治理与水安全重点实验室郑州450003 天津大学水利工程安全与仿真国家重点试验室天津300072

异重流稳定水跃是非连续异重流中的一种典型流态,反映着由急流过渡到缓流时的运动特征。其运动过程伴随着复杂的耗能和掺混过程,目前的研究还不能很好地解释两者间的对应关系。本文利用水槽实验,观测了泥沙异重流在斜坡与平底交界处的... 详细信息

异重流稳定水跃是非连续异重流中的一种典型流态,反映着由急流过渡到缓流时的运动特征。其运动过程伴随着复杂的耗能和掺混过程,目前的研究还不能很好地解释两者间的对应关系。本文利用水槽实验,观测了泥沙异重流在斜坡与平底交界处的水跃现象,通过推导水头损失公式,分析了水跃耗能和掺混关系。研究发现增加入口含沙量或初始水深,或减小入口流速,均导致水跃强度减弱,共轭水深比值减小,异重流层厚度增加受限。这种实验现象伴随着水跃耗能过程的强弱,入口含沙量或初始水深的增加,或入口流速的减小,均导致水跃前后的水头损失降低,减少了被卷吸的上层清水流量,共轭水深比值进而减小,异重流层密度也有小幅降低。通过对异重流水跃的耗能过程分析,可知耗能减小表明流层间的紊动强度减弱,能有效地降低异重层和上层清水的掺混速率。通过回归分析,发现共轭水深比值与水头损失比∆hf/hf1,以及∆hf/h f1与掺混系数K_(Q)均呈现出正比例线性关系。本文推导的能量指标是分析异重流水跃过程、揭示异重流掺混机制过程的可行方法。

关键词：泥沙异重流稳定水跃共轭水深水头损失局部掺混

正交约束域适应的跨工况滚动轴承剩余使用寿命预测方法

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电子与信息学报 2024年第3期46卷 1043-1050页

作者：韩延林志超黄庆卿向敏文瑞张焱重庆邮电大学自动化学院重庆400065 重庆邮电大学工业互联网研究院重庆401122

针对跨工况轴承剩余使用寿命(RUL)预测模型的决策边界不明显、特征可辨识性低的问题,该文提出一种正交约束的最大分类器差异方法(MCD_OC)。首先,将采集的轴承原始振动信号进行快速傅里叶变换,得到振动信号的频域信号作为模型的输入;然后... 详细信息

针对跨工况轴承剩余使用寿命(RUL)预测模型的决策边界不明显、特征可辨识性低的问题,该文提出一种正交约束的最大分类器差异方法(MCD_OC)。首先,将采集的轴承原始振动信号进行快速傅里叶变换,得到振动信号的频域信号作为模型的输入;然后,通过卷积神经网络(CNN)和门控循环神经网络(GRU)提取轴承信号的深层时空特征,利用最大分类器差异将源域和目标域特征对齐,并对目标域轴承深层特征进行正交约束,增大无标签目标域样本特征之间的可辨识性;最后,基于轴承寿命数据集开展了跨工况轴承寿命预测对比实验,对该文所提方法进行评估,并在多组实验中取得最优结果。

关键词：滚动轴承剩余使用寿命正交约束最大分类器差异