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煤中可溶性有机质荧光光谱特征及其对微量元素赋存的影响

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煤炭学报 2017年第1期42卷 257-266页

作者：孟庆俊李小孟高波冯启言李梓菡何文元中国矿业大学环境与测绘学院江苏徐州221116

煤中微量元素的赋存状态有多种形式,其中大部分微量元素都能与煤中有机质结合。煤中有机质的含量与煤的煤化程度有一定联系。实验选取了褐煤、烟煤、无烟煤3种共7个煤样进行分析,采用ICP-AES方法测定了煤中微量元素含量,采用三维荧光光... 详细信息

煤中微量元素的赋存状态有多种形式,其中大部分微量元素都能与煤中有机质结合。煤中有机质的含量与煤的煤化程度有一定联系。实验选取了褐煤、烟煤、无烟煤3种共7个煤样进行分析,采用ICP-AES方法测定了煤中微量元素含量,采用三维荧光光谱仪分析了3种煤的可溶性有机质(DOM)的荧光光谱特征,并运用平行因子法对荧光数据进行了深入分析,探讨了煤中溶解性有机质与煤中微量元素赋存形态之间的关系。结果表明,煤中不同微量元素在褐煤、烟煤、无烟煤中的分布有差异,As,Mg,Cd,Mn在褐煤中含量最高,li,Sr在无烟煤中含量最高,而Cu,Co在3种煤中含量差异不明显。褐煤中可溶性有机质以腐殖酸类为主,烟煤的荧光基团有腐殖类和类蛋白类,而无烟煤中未能检测出荧光峰。荧光强度亦随着煤化程度的递增呈现递减。煤中As和Mg的赋存与煤中可溶性有机质可能存在着一定联系,即煤中可溶性腐殖酸荧光强度越大,As和Mg越丰富,而li和Sr则相反。

关键词：煤微量元素溶解性有机质三维荧光光谱平行因子

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang yang Jianfeng Zheng Guoyu Wang Yifei Gao Yatao yang Jia li Xiaojin Han yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Ethanol

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体外预应力加固混凝土双向板的试验研究

合肥工业大学学报（自然科学版） 2007年第4期30卷 478-481,501页

作者：胡成吴元李延和合肥工业大学土木建筑工程学院安徽合肥230009 东南大学土木工程学院江苏南京210096 江苏建华建设有限责任公司江苏南京210009

体外预应力加固技术已广泛应用于RC梁的加固工程中。文章进行了单向张拉体外预应力钢筋加固RC双向板的试验和理论研究,探讨了体外预应力对双向板承载能力工作性能的影响,分析说明了体外预应力钢筋在双向板的中间板带“集中布置”时的加... 详细信息

体外预应力加固技术已广泛应用于RC梁的加固工程中。文章进行了单向张拉体外预应力钢筋加固RC双向板的试验和理论研究,探讨了体外预应力对双向板承载能力工作性能的影响,分析说明了体外预应力钢筋在双向板的中间板带“集中布置”时的加固效果较好。

关键词：加固体外预应力钢筋混凝土双向板极限荷载

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全光网节点规模的分析

中国激光 2001年第9期28卷 851-853页

作者：郑小平李艳和张汉一郭奕理清华大学电子工程系北京100084

导出了光信噪比与光节点数量 ,掺铒光纤放大器 (EDFA)噪声系数 ,增益的关系公式 ,并分析了光节点数目与EDFA特性参数的关系。分析表明 ,当光节点中EDFAs设置成输入EDFA补偿节点损耗 ,输出EDFA补偿光纤损耗的工作方式时 ,要保持光信号的... 详细信息

导出了光信噪比与光节点数量 ,掺铒光纤放大器 (EDFA)噪声系数 ,增益的关系公式 ,并分析了光节点数目与EDFA特性参数的关系。分析表明 ,当光节点中EDFAs设置成输入EDFA补偿节点损耗 ,输出EDFA补偿光纤损耗的工作方式时 ,要保持光信号的信噪比不低于 2 0dB ,则光节点数目最多为 19左右 ,改善EDFA的噪声系数对提高光节点数目的作用不大 ;如降低光节点内部损耗 ,优化两个EDFA的增益 ,可以最大程度地提高网络节点规模 ,网络节点数最大可达 5 6。

关键词：全光网光节点掺铒光纤放大器光纤通信

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论现代生活方式

宁夏党校学报 2003年第5期5卷 55-60页

作者：李彦和中共宁夏回族自治区委党校宁夏银川750021

改革、环境革命、信息化和知识经济等催生了现代生活方式。现代生活方式具有时代性、创新性,更加追求精神消费、共生性、个体性、多样性等特点。要从营造消费文化、创造丰富的物质财富和优美的生活环境、全面完善生活方式内容等方面创... 详细信息

改革、环境革命、信息化和知识经济等催生了现代生活方式。现代生活方式具有时代性、创新性,更加追求精神消费、共生性、个体性、多样性等特点。要从营造消费文化、创造丰富的物质财富和优美的生活环境、全面完善生活方式内容等方面创造现代生活方式,与此同时要摒弃不健康的生活方式。

关键词：消费文化生活方式现代生活方式

Epigenetics in the modern era of crop improvements

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Science China life Sciences 2025年

作者： yan Xue Xiaofeng Cao Xiangsong Chen Xian Deng Xingwang Deng Yong Ding Aiwu Dong Chengguo Duan Xiaofeng Fang Lei Gong Zhizhong Gong Xiaofeng Gu Chongsheng he Hang he Shengbo he Xinjian he yan he Yuehui he Guifang Jia Danhua Jiang Jianjun Jiang Jinsheng Lai Zhaobo Lang Chenlong li Qing li Xingwang li Bao liu Bing liu Xiao Luo Yijun Qi Weiqiang Qian Guodong Ren Qingxin Song Xianwei Song Zhixi Tian Jiawei Wang Yuan Wang liang Wu Zhe Wu Rui Xia Jun Xiao lin Xu Zhengyi Xu Wenhao yan Hongchun yang Jixian Zhai Yijing Zhang Yusheng Zhao Xuehua Zhong Daoxiu Zhou Ming Zhou Yue Zhou Bo Zhu Jiankang Zhu Qikun liu College of life Sciences Institute of Life Science and Green Development Hebei University Biotechnology Research Institute Chinese Academy of Agricultural Sciences College of Biology Hunan Key Laboratory of Plant Functional Genomics and Developmental Regulation Hunan Engineering and Technology Research Center of Hybrid Rapeseed Hunan University Institute of Advanced Agricultural Sciences School of Advanced Agricultural Sciences Peking University State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern Agriculture South China Agricultural University National Institute of Biological Sciences Key Laboratory of Seed Innovation Institute of Genetics and Developmental Biology Chinese Academy of Sciences School of Advanced Agricultural Sciences Peking-Tsinghua Center for Life Sciences Peking University Synthetic and Functional Biomolecules Center Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education College of Chemistry and Molecular Engineering Peking University Key Laboratory of Seed Innovation State Key Laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences State Key Laboratory of Wheat Improvement Peking University Institute of Advanced Agricultural Sciences Shandong Laboratory of Advanced Agricultural Sciences in Weifang State Key Laboratory of Crop Stress Adaptation and Improvement School of Life Sciences Henan University State Key Laboratory of Maize Bio-breeding National Maize Improvement Center Department of Plant Genetics and Breeding China Agricultural University Frontiers Science Center for Molecular Design Breeding China Agricultural University Center for Crop Functional Genomics and Molecular Breeding China Agricultural University Sanya Institute of China Agricultural University Hainan Yazhou Bay Seed Laboratory Institute of Advan

Epigenetic mechanisms are integral to plant growth, development, and adaptation to environmental stimuli. Over the past two decades,our comprehension of these complex regulatory processes has expanded remarkably, producing a substantial body of knowledge on both locus-specific mechanisms and genome-wide regulatory patterns. Studies initially grounded in the model plant Arabidopsis have been broadened to encompass a diverse array of crop species, revealing the multifaceted roles of epigenetics in physiological and agronomic traits. With recent technological advancements, epigenetic regulations at the single-cell level and at the large-scale population level are emerging as new focuses. This review offers an in-depth synthesis of the diverse epigenetic regulations, detailing the catalytic machinery and regulatory functions. It delves into the intricate interplay among various epigenetic elements and their collective influence on the modulation of crop traits. Furthermore, it examines recent breakthroughs in technologies for epigenetic modifications and their integration into strategies for crop improvement. The review underscores the transformative potential of epigenetic strategies in bolstering crop performance, advocating for the development of efficient tools to fully exploit the agricultural benefits of epigenetic insights.

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Lung-targeted polyzwitterionic lipid nanoparticles for effective treatment of lung inflammation

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Science China Chemistry 2025年

作者： Wen Zhang Jiaxin li Nan Wang Muzi li Chen Peng Xinyue Zhang Guanghui Ouyang yan li Beijing Key Laboratory for Bioengineering and Sensing Technology School of Chemistry and Biological Engineering University of Science and Technology Beijing CAS Key Laboratory of Colloid Interface and Chemical Thermodynamics Institute of Chemistry Chinese Academy of Sciences

lipid nanoparticles (LNPs) are non-viral nucleic acid delivery systems that show great potential in vaccine development and disease treatment. Although LNPs are particularly advantageous for in vivo delivery, the wide application of LNPs is impeded as their systemic delivery of nucleic acid drugs to extrahepatic tissues remains highly challenging. To address this issue, we developed lung-targeted polyzwitterionic LNPs with zwitterionic polymer poly(2-methyacryloyloxyethyl phosphorylcholine)(PMPC) modified 1,2-dimyristoyl-sn-glycerol lipid for the delivery of small interfering RNA (siRNA). Three libraries with 90PMPC-LNPs@siRNA were established. The polyzwitterionic PMPC-LNPs had high siRNA encapsulation efficiency of about90%. The findings revealed that polyzwitterionic PMPC-LNPs@siRNA absorbed protein corona with the main component of Vitronectin, mediating lung-targeted delivery of siRNA. With good cellular uptake and endo/lysosomal escape ability, in vitro and in vivo studies demonstrated that polyzwitterionic PMPC-LNPs with siRNA against tumor necrosis factor-α (TNF-α) could significantly down-regulate the TNF-α in mRNA and protein levels, and improved the pathological features of lung inflammation. Polyzwitterionic PMPC-LNPs@siRNA achieved safe and efficient treatment of lung inflammation. Therefore, this work offered a promising siRNA therapeutic approach for lung diseases.

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某复杂铝合金盒形件模具降载方案的优化研究

热加工工艺 2018年第5期47卷 135-138页

作者：冯岩李国俊贺晨晨中北大学材料科学与工程学院

针对一种形状并非完全对称的盒形件,设计了2种不同结构的凸模,并进行了等温挤压。利用有限元模拟分析软件模拟了挤压过程,分析比较了2种方案的挤压成形结果、凸模的载荷-行程曲线、凸模的等效应变分布等,获得优化的挤压方案,并通过试验... 详细信息

针对一种形状并非完全对称的盒形件,设计了2种不同结构的凸模,并进行了等温挤压。利用有限元模拟分析软件模拟了挤压过程,分析比较了2种方案的挤压成形结果、凸模的载荷-行程曲线、凸模的等效应变分布等,获得优化的挤压方案,并通过试验对模拟结果进行了验证。结果表明,带有内孔的凸模可以有效地降低挤压过程中的载荷,并获得合格的零件。

关键词：铝合金热挤压盒形件数值模拟

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输卵管镜在不孕症诊治中的应用

中国内镜杂志 2006年第4期12卷 437-438页

作者：胡小良徐宏里李延河暨南大学第二临床医学院深圳市人民医院妇产科广东深圳518020

目的探讨输卵管镜应用于不孕症的价值。方法于2003年4月￣2005年3月对13例不孕症患者在施行宫腔镜与腹腔镜联合手术的同时施行经宫颈输卵管镜检查。观察患者宫腔、腹腔及输卵管腔,输卵管腔的观察内容为黏膜色泽、皱襞是否清晰或平坦、... 详细信息

目的探讨输卵管镜应用于不孕症的价值。方法于2003年4月￣2005年3月对13例不孕症患者在施行宫腔镜与腹腔镜联合手术的同时施行经宫颈输卵管镜检查。观察患者宫腔、腹腔及输卵管腔,输卵管腔的观察内容为黏膜色泽、皱襞是否清晰或平坦、毛细血管是否正常或稀少、管腔有无粘连及管腔内组织。结果腹腔镜显示盆腔粘连8例、多囊卵巢1例、盆腔正常4例。宫腔镜显示慢性宫内膜炎5例、宫内膜息肉2例、宫腔正常6例;宫腔镜下输卵管口插管通液术后输卵管双侧通畅8例,一侧通畅3例,双侧通而不畅1例,双侧阻塞1例。输卵管镜成功进入8例患者的12条输卵管腔。其中全程观察5条,半程观察3条,少于半程观察4条。输卵管腔全程正常5条,输卵管腔观察段正常4条(其余段输卵管未被观察到),3条输卵管腔异常。3条异常者输卵管内膜苍白或稍苍白,黏膜皱襞欠清晰或平坦,毛细血管少或很少,其中2例有蛛网状粘连。14条输卵管未能被插入输卵管镜。2条输卵管发生穿孔,但无出血。结论输卵管镜对输卵管性不孕有一定的诊断和治疗作用,但由于目前技术的限制,其诊治效果有限。

关键词：不育女(雌)性输卵管镜检查宫腔镜检查腹腔镜检查