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Regulating ethane and ethylene synthesis by proton corridor microenvironment for CO_(2) electrolysis

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Journal of Energy Chemistry 2023年第12期87卷 368-377,I0010页

作者： Xiaowen Zhang Bohua Ren Hao Li Shuxuan liu Haoyang Xiong silong Dong Yifan Li Dan Luo Yi Cui Guobin Wen Xin Wang South China Academy of Advanced Optoelectronics International Academy of Optoelectronics at ZhaoqingSouth China Normal UniversityGuangzhou 510006GuangdongChina Department of Chemical Engineering Waterloo Institute for NanotechnologyUniversity of Waterloo200 University Avenue WestWaterlooOntario N2L 3G1Canada School of Nano Technology and Nano Bionics University of Science and Technology of ChinaHefei 230026AnhuiChina i-lab Nano-X Vacuum Interconnected WorkstationSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123JiangsuChina State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and DevicesCollege of Chemistry and Chemical EngineeringNational Supercomputer Centers in ChangshaHunan UniversityChangsha 410082HunanChina

Electrocatalytic reduction of carbon dioxide is one of the most effective strategies to achieve carbon neutrality and energy *** high-value multi-carbon products have been widely studied,limited electrocatalysts have been reported for the selective conversion of *** importantly,the factors tuning the selectivity between ethane and ethylene have not been ***,Zn@Cu nanowire arrays(Zn@Cu-NWAs) catalyst is proposed to stimulate the maintenance of efficient CO_(2)-to-C_(2)H_(6) conversion at high current ***,in order to investigate the factors affecting the interconversion between ethane and ethylene,the counterpart catalyst that facilitates C–C coupling to ethylene was also ***-of-flight secondary-ion mass spectroscopy(TOF-SIMS),in-situ Raman spectroscopy,and simulation results show that Zn@Cu-NWAs can provide a localized proton corridor environment for the formation of ethane,accelerating the further proton-coupled CO_(2) reduction reaction(CO_(2)RR)***,this catalyst delivered an ethane Faraday efficiency of over 65% at-1.14 V *** with a total current density of 142.3 mA/cm^(2).This work provides a new perspective on regulating the local microenvironment to modify the selectivity of multi-carbon products.

关键词： Proton microenvironment CO_(2)reduction C2+product Selective conversion Cu-Zn materials

A circuit from dorsal hippocampal CA3 to parvafox nucleus mediates social novelty preference deficits induced by chronic social defeat stress

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中国药理学与毒理学杂志 2023年第7期37卷 536-537页

作者： ZOU Rousi liu Yang DENG silong WANG Fang CHEN Jianguo Department of Pharmacology Tongji Medical CollegeHuazhong University of Science and Technology

OBJECTIVE The preference for social novelty is crucial to the social life of humans and ***,the neural mechanisms underlying social novelty preference are poorly *** hippocampal CA3 (dCA3) is an important brain area that responds to social defeat stress,and the neural circuitry of dCA3→lateral septum (LS) participates in the context-associated ***,the parvafox nucleus (PFN) Foxb1+neurons regulate the defensive reaction to life-threatening ***,we investigate a cell-specific circuit of dCA3CaMKⅡα+→dorsal LSGABA+→PFNFoxb1+in social novelty *** Chronic social defeat stress (CSDS) and three-chamber social interaction test were performed in adult male C57BL/6J mice to detect social *** and chemical-genetic experiments were conducted to regulate the *** CSDS reduced the preference for social novelty in mice and the response of dCA3CaMKⅡα+neurons during approach to an unfamiliar mouse was impaired by *** inhibition of dCA3CaMKⅡα+→dLS projection reduced the preference for the unfamiliar mouse versus a familiar ***,optogenetic activation of dCA3CaMKⅡα+→dLS projection rescued the preference for social novelty of CSDS-treated *** dLSGABA+→PFN projection activation regulated the preference for social novelty in *** activation of PFNFoxb1+→lPAG projection reduced the preference for a familiar C57BL/6J mouse versus a novel object in control *** decreased the excitability of dCA3CaMKⅡα+neurons by up-regulation of Kir2.4 (Kcnj14)*** Our present study suggested that activation of a cell-specific circuit of dCA3CaMKⅡα+→dLSGABA+→PFNFoxb1+→lPAG reverses the deficits of social novelty preference in defeated mice,and inhibition of this circuit reduces the preference for social *** circuit that regulates the preference for social novelty deficits may provide a new information for the potential therapeutic t

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GH3625合金在75%Na_(2)SO_(4)-25%NaCl环境中热腐蚀行为研究

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大型铸锻件 2024年第2期 57-63页

作者：熊健强刘仕伟代琦江辉盛耀戈管红亮符思龙二重(德阳)重型装备有限公司四川德阳618000

将GH3625合金置于750℃下,75%Na_(2)SO_(4)-25%NaCl熔盐环境中以研究GH3625合金的热腐蚀行为,使用扫描电镜、能谱仪以及X射线衍射仪等设备对腐蚀后合金表面形貌、元素分布以及物相鉴定等进行研究分析。研究结果表明:组织为奥氏体等轴晶... 详细信息

将GH3625合金置于750℃下,75%Na_(2)SO_(4)-25%NaCl熔盐环境中以研究GH3625合金的热腐蚀行为,使用扫描电镜、能谱仪以及X射线衍射仪等设备对腐蚀后合金表面形貌、元素分布以及物相鉴定等进行研究分析。研究结果表明:组织为奥氏体等轴晶的GH3625合金腐蚀增重曲线呈现“两级”增重规律。合金在熔盐中腐蚀后,由腐蚀层最外层到合金基体结构依此为尖晶状NiO和片层状NiCr_(2)O_(4)、存在少许缺陷但相对致密的Cr_(2)O_(3)氧化层、带有孔洞的“蜂窝”状Ni_(2)S_(3)硫化层、基体贫Cr层以及合金基体。GH3625合金在750℃下,75%Na_(2)SO_(4)-25%NaCl熔盐环境中造成氧化膜失效的主要腐蚀反应为Cr_(2)O_(3)与Cl-以及Na_(2)O的反应,反应生成CrO_(2)Cl_(2)和NiCr_(2)O_(4)铬酸盐。

关键词： GH3625合金熔盐腐蚀表面形貌氧化反应腐蚀机制

Nonlinear dynamics of cell migration in anisotropic microenvironment

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Chinese Physics B 2021年第9期30卷 166-177页

作者： Yanping liu Da He Yang Jiao Guoqiang Li Yu Zheng Qihui Fan Gao Wang Jingru Yao Guo Chen silong Lou Liyu liu Chongqing Key Laboratory of Soft Condensed Matter Physics and Smart Materials College of PhysicsChongqing UniversityChongqing 401331China Spine Surgery Beijing Jishuitan HospitalBeijing 100035China Department of Physics Arizona State UniversityTempeArizona 85287USA Materials Science and Engineering Arizona State UniversityTempeArizona 85287USA Beijing National Laboratory for Condensed Matter Physics and CAS Key Laboratory of Soft Matter Physics Institute of PhysicsChinese Academy of Sciences(CAS)Beijing 100190China Department of Neurosurgery Chongqing University Cancer HospitalChongqing 400030China

Cell migration in anisotropic microenvironment plays an important role in the development of normal tissues and organs as well as neoplasm progression,e.g.,osteogenic differentiation of embryonic stem cells was facilitated on stiffer substrates,indicating that the mechanical signals greatly affect both early and terminal differentiation of embryonic stem ***,the effect of anisotropy on cell migration dynamics,in particular,in terms of acceleration profiles which is important for recognizing dynamics modes of cell migration and analyzing the regulation mechanisms of microenvironment in mechanical signal transmission,has not been systematically *** this work,we firstly rigorously investigate and quantify the differences between persistent random walk and anisotropic persistent random walk models based on the analysis of cell migration trajectories and velocity auto-covariance function,both qualitatively and ***,we introduce the concepts of positive and negative anisotropy based on the motility parameters to study the effect of anisotropy on acceleration profiles,especially the nonlinear decrease and non-monotonic *** particularly elaborate and discuss the mechanisms,and physical insights of non-monotonic behaviors in the case of positive anisotropy,focusing on the force exerted on migrating ***,we analyze two types of in vitro cell migration experiments and verify the universality of nonlinear decrease and the consistence of non-monotonic behaviors with numerical *** conclude that the anisotropy of microenvironment is the cause of the non-monotonic and nonlinear dynamics,and the anisotropic persistent random walk can be as a suitable tool to analyze in vitro cell migration with different combinations of motility *** analysis provides new insights into the dynamics of cell migration in complex microenvironment,which also has implications in tissue engineering and cancer research.

关键词： cell migration nonlinear behavior motility parameter acceleration profile anisotropic microenvironment

Nitrogen Deposition and Its Spatial Pattern in Main Forest Ecosystems along North-South Transect of Eastern China

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Chinese Geographical Science 2014年第2期24卷 137-146页

作者： ZHAN Xiaoyun YU Guirui HE Nianpeng FANG Huajun JIA Bingrui ZHOU Mei WANG Chuankuan ZHANG Junhui ZHAO Guangdong WANG silong liu Yunfen YAN Junhua Synthesis Research Center of Chinese Ecosystem Research Network Key Laboratory of Ecosystem Network Observation and ModelingInstitute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Botany Chinese Academy of Sciences College of Ecology and Environmental Science Inner Mongolia Agricultural University College of Forestry Northeast Forestry University Institute of Applied Ecology Chinese Academy of Sciences Institute of Forest Ecology Environment and Protection Chinese Academy of Forestry South China Botany Garden Chinese Academy of Sciences

A continuous three-year observation(from May 2008 to April 2011)was conducted to characterize the spatial variation of dissolved inorganic nitrogen(DIN)deposition at eight main forest ecosystems along the north-south transect of eastern China(NSTEC).The results show that both throughfall DIN deposition and bulk DIN deposition increase from north to south along the *** DIN deposition varies greatly from 2.7 kg N/(ha·yr)to 33.0 kg N/(ha·yr),with an average of 10.6 kg N/(ha·yr),and bulk DIN deposition ranges from 4.1 kg N/(ha·yr)to 25.4 kg N/(ha·yr),with an average of 9.8 kg N/(ha·yr).NH4+-N is the dominant form of DIN deposition at most sampling ***,the spatial variation of DIN deposition is controlled mainly by ***,in the northern part of the NSTEC,bulk DIN deposition is 17%higher than throughfall DIN deposition,whereas the trend is opposite in the southern part of the *** results demonstrate that DIN deposition would likely threaten the forest ecosystems along the NSTEC,compared with the critical loads(CL)of N deposition,and DIN deposition in this region is mostly controlled by agricultural activities rather than industrial activities or transportation.

关键词： forest ecosystem nitrogen deposition NH4+-N NO3-N eastern China

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相似尺度图像融合算法

计算机研究与发展 2005年第12期42卷 2126-2131页

作者：陈涛易沫刘忠轩彭思龙中国科学院自动化研究所国家专用集成电路设计工程研究中心北京100080

提出了一种新的融合思想,即图像应在相似尺度(si milar scale,SS)上进行融合·当融合低分辨率多光谱图像与高分辨率全色图像时,一般的方法没有考虑到插值的多光谱图像和高分辨率的全色图像的尺度不一致性·基于相似尺度的思想,图像融合... 详细信息

提出了一种新的融合思想,即图像应在相似尺度(si milar scale,SS)上进行融合·当融合低分辨率多光谱图像与高分辨率全色图像时,一般的方法没有考虑到插值的多光谱图像和高分辨率的全色图像的尺度不一致性·基于相似尺度的思想,图像融合算法如下·首先,使用“劋trous”离散小波变换分解高分辨率全色图像,使其低通分量与插值后的多光谱图像具有相似的尺度·然后,用加权多尺度基本形式(weighted mutlitscale fundamental form,WMFF)来融合它们得到合成的最低频带·最后,“劋trous”逆小波变换用来重建高分辨率的多光谱图像·与其他的基于小波变换的图像融合算法相比,基于相似尺度的融合方法取得了更好的融合结果·

关键词：图像融合相似尺度加权多尺度基本形式小波变换

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一种基于先验知识的分水线彩色图像分割方法

计算机工程 2006年第21期32卷 28-30页

作者：刘佳璐杨明辉彭思龙国家专用集成电路设计工程技术研究中心中国科学院自动化所北京100080

提出了一个结合彩色信息的分水线图像分割方法,在LUV颜色空间的分水线图像上,使用贝叶斯推理的图像分割方法。对图像进行LUV彩色空间上的分水线变换,在分水线图像上进行基于彩色信息的各个区域能量的计算,通过选择最小能量的目标,依次... 详细信息

提出了一个结合彩色信息的分水线图像分割方法,在LUV颜色空间的分水线图像上,使用贝叶斯推理的图像分割方法。对图像进行LUV彩色空间上的分水线变换,在分水线图像上进行基于彩色信息的各个区域能量的计算,通过选择最小能量的目标,依次找出最理想的目标区域。设计了一个先验密度惩罚图像当中分水线变换后的相似的区域,图像分割进而变成对目标子集的最大后验估计。逐步地找出最理想目标区域和背景区域。这一方法同时结合使用了彩色信息和空间信息;可以有效地解决分水线变换后的过分割问题,利用了先验知识和彩色信息。实验结果显示,该方法有较好的分割结果。

关键词：贝叶斯框架 LUV色彩空间分水线变换 MAP估计

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低氧气氛下煤粉燃烧特性及动力学

锅炉技术 2020年第1期51卷 37-41页

作者：刘煜陈思龙闫凯上海锅炉厂有限公司上海200245

采用热重分析仪研究了不同煤粉在烟气气氛下的燃烧特性,考虑了升温速率和氧气浓度对燃烧特性的影响。研究结果表明:低氧条件、高升温速率下,煤粉的TG、DTG曲线均向高温区靠近,燃烧速率变慢,燃尽时间增长;改变氧气浓度和升温速率对煤的... 详细信息

采用热重分析仪研究了不同煤粉在烟气气氛下的燃烧特性,考虑了升温速率和氧气浓度对燃烧特性的影响。研究结果表明:低氧条件、高升温速率下,煤粉的TG、DTG曲线均向高温区靠近,燃烧速率变慢,燃尽时间增长;改变氧气浓度和升温速率对煤的着火温度影响不大,在一定氧浓度(5%~15%)范围内,高水分低阶煤采用烟气干燥输送的制粉系统,能满足其安全性要求;氧气浓度和升温速率主要对煤的燃烧阶段产生影响,随着升温速率的升高和氧浓度的降低,燃尽温度明显升高,且氧浓度对燃烧特征参数的影响大于升温速率的影响。此外,采用Coats-Redfern积分法对煤粉在程序升温过程中的燃烧反应做了相应的动力学分析。结果表明:氧气浓度和升温速率的变化均对活化能产生影响,且随着氧气浓度的降低,煤阶对活化能的影响逐渐减弱。

关键词：热重分析低氧浓度燃烧特性动力学分析

基于AHP-熵权法的水环境承载力模糊综合评价

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环境科学与技术 2021年第9期44卷 206-212页

作者：王晓艳章四龙刘磊北京师范大学水科学研究院北京100875 北京师范大学珠海校区水安全研究院广东珠海519087 北京师范大学珠海校区粤港水安全保障联合实验室广东珠海519087

针对水环境承载力评价存在的不确定性和模糊性问题,该研究采用层次分析法和熵权法进行组合赋权,利用模糊综合评价法对粤港澳大湾区9个城市的水环境承载力进行评价,并引入障碍度模型确定影响水环境承载力的主要障碍度因素。结果表明:2013... 详细信息

针对水环境承载力评价存在的不确定性和模糊性问题,该研究采用层次分析法和熵权法进行组合赋权,利用模糊综合评价法对粤港澳大湾区9个城市的水环境承载力进行评价,并引入障碍度模型确定影响水环境承载力的主要障碍度因素。结果表明:2013-2018年9个城市的水环境承载力总体呈上升趋势,但城市间的变化差异明显;9个城市水环境承载力的障碍指标差异明显,其中人均水资源量以20.7%的障碍度均值成为首要障碍度指标;通过障碍度频率分析可得9个城市的主要障碍度指标包括人均水资源量、生态用水率、万元GDP污(废)水排放量和第三产业比重,这4项指标的频率均为89%。将该方法应用于区域水环境承载力的评价,其结果可为区域水环境的管理和相关政策的制定提供依据。

关键词：水环境承载力 AHP-熵权法模糊综合评价障碍度粤港澳大湾区