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Factors contributing to the oxygen concentration over the Qinghai-Tibetan Plateau and its contribution rate calculation

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Science China Earth Sciences 2024年第2期67卷 497-509页

作者： Peijun SHI Ying ZHANG yanqiang chen Wenquan ZHU Xiaokang HU Heyi YANG Lu JIANG Yonggui MA Haiping TANG State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing100875China Key Laboratory of Environmental Change and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing100875China The Institute for Disaster Management and Reconstruction Sichuan UniversityChengdu610065China Academy of Plateau Science and Sustainability People’s Government of Qinghai Province&Beijing Normal UniversityXining810016China

A decline in atmospheric oxygen concentration is projected in the 21st century given the background of global *** Qinghai-Tibetan Plateau is located at a high altitude,and thus,it faces a hypoxia challenge;however,knowledge of the factors contributing to its atmospheric oxygen concentration is still ***,we conducted joint observations of ecosystem oxygen production and carbon sinks and near-surface atmospheric oxygen concentrations on the Qinghai-Tibetan Plateau and meteorological elements at Beijing Fangshan *** seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen *** results indicate that solar radiation,atmospheric humidity,and ecosystem oxygen consumption and production have a significant impact on the atmospheric oxygen concentration,and the impact shows temporal and spatial *** significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing *** findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of *** better understand the oxygen dynamics of the Qinghai-Tibetan Plateau,we recommend further field observations of soil respiration and vegetation photosynthesis to clarify the contributions of carbon storage,carbon sinks and other factors to the near-surface atmospheric oxygen concentration.

关键词： Qinghai-Tibetan Plateau Oxygen concentration Relative contribution rate Air temperature Vegetation

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水泥基材料中Ca^(2+)对矿化微生物的碳酸酐酶产量、活性和矿化的影响

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材料导报 2024年第8期38卷 131-136页

作者：张俊杰陈燕强钱春香东南大学材料科学与工程学院南京211189 东南大学绿色建材与固碳研究中心南京211189 中国建筑行业微生物矿化技术重点实验室南京211189 东南大学江苏省土木工程材料重点实验室南京211189

本工作针对一种适用于水泥基材料的耐碱矿化微生物,研究了水泥基材料中Ca^(2+)浓度变化(0~5 mmol/L)对矿化微生物的产酶量、碳酸酐酶活性以及诱导CaCO_(3)矿化能力的影响。对分离纯化不同Ca^(2+)浓度菌液中的碳酸酐酶进行酶产量测定,并... 详细信息

本工作针对一种适用于水泥基材料的耐碱矿化微生物,研究了水泥基材料中Ca^(2+)浓度变化(0~5 mmol/L)对矿化微生物的产酶量、碳酸酐酶活性以及诱导CaCO_(3)矿化能力的影响。对分离纯化不同Ca^(2+)浓度菌液中的碳酸酐酶进行酶产量测定,并通过测定矿化微生物的细菌生长曲线和单菌产酶量分析Ca^(2+)浓度对其的影响机理;基于酯酶法测定不同Ca^(2+)浓度下碳酸酐酶的活性,并利用FTIR测定官能团,分析二级结构变化和氢键变化,进而得到Ca^(2+)浓度对碳酸酐酶活性的影响机理;最后基于热重分析不同Ca^(2+)浓度溶液中矿化微生物的诱导矿化能力,并测定矿化产物晶形。试验结果表明,当Ca^(2+)浓度为2.5 mmol/L时,矿化微生物生长增殖最快,单菌产酶量最高,因此整体酶产量最高;碳酸酐酶活性在Ca^(2+)浓度为5 mmol/L时达到最大值,但Ca^(2+)会破坏碳酸酐酶结构的有序性;当Ca^(2+)浓度为5 mmol/L时,矿化微生物的诱导矿化能力最强,矿化3 d后Ca(OH)_(2)向CaCO_(3)的转化率达到82.67%,且得到的CaCO_(3)晶体形貌主要为球状或椭圆状。

关键词：矿化微生物碳酸酐酶酶产量酶活性诱导矿化

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Carbon Emission Risk and Governance

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International Journal of Disaster Risk Science 2022年第2期13卷 249-260页

作者： Lu Jiang Xiaokang Hu Gangfeng Zhang yanqiang chen Honglin Zhong Peijun Shi Academy of Plateau Science and Sustainability People’s Government of Qinghai Province and Beijing Normal UniversityXining 810016China State Key Laboratory of Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Academy of Disaster Reduction and Emergency Management Ministry of Emergency Management and Ministry of EducationBeijing Normal UniversityBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Institute of Blue and Green Development Weihai Institute of Interdisciplinary ResearchShandong UniversityWeihai 264209China

Within the hazard and disaster risk research field, explicitly treating carbon emissions as a hazard remains rather nascent. Applying hazard and disaster risk research perspectives to seek new insights on integrated mitigation and adaptation approaches and policy measures is equally elusive. Since China’s pledge to achieve carbon neutrality by 2060, the ‘‘dual carbon” goals of carbon emission peaking and neutrality have stimulated nationwide attention, research, and policies and action *** to ensure that the transition pathways are on track and well-contextualized is one of the crucial challenges for policymakers and practitioners. This article examines the‘‘risks” of missing the carbon neutrality goal at a regional scale in China, denoted as Carbon Emission Risk(CER).Carbon emissions(CE) as hazard, combined with the human socioeconomic system as exposure and human living environment, constitute the regional carbon emission environmental risk system. The ‘‘risks” of missing(or achieving) the carbon neutrality target for any region at any time, the article argues, is essentially determined by the ratio of CE to carbon absorption(CA, for uptake and removal). These variables are modified by a broadly defined ‘‘vulnerability coefficient”(Cv) that embodies both the potential for changes(decreasing CE and increasing CA), and the uncertainties of measuring CE and CA. Thus,the ratio of CE to CA is a measure of reality at any moment of time, whereas Cv indicates the overall propensity or capacity for moving the CE/CA ratio towards 1, that is,realizing carbon neutrality. Based on our calculation, CER at the provincial level in eastern China is higher than in western China. The article also calls for strengthening CER research and summarizes key measures for carbon emission risk governance.

关键词： Carbon emission risks Carbon neutrality Low-carbon economy Risk governance Vulnerability coefficient

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Empowering smart city situational awareness via big mobile data

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 286-307页

作者： Zhiguang SHAN Lei SHI Bo LI yanqiang ZHANG Xiatian ZHANG Wei chen State Information Center Beijing100045China School of Computer Science and Engineering Beihang UniversityBeijing100191China Zhongguancun Laboratory Beijing100094China Beijing Tendcloud Tianxia Technology Co. Ltd.Beijing100027China The State Key Lab of CAD&CG Zhejiang UniversityHangzhou310027China

Smart city situational awareness has recently emerged as a hot topic in research societies,industries,and governments because of its potential to integrate cutting-edge information technology and solve urgent challenges that modern cities *** example,in the latest five-year plan,the Chinese government has highlighted the demand to empower smart city management with new technologies such as big data and Internet of Things,for which situational awareness is normally the crucial first *** traditional static surveillance data on cities have been available for decades,this review reports a type of relatively new yet highly important urban data source,i.e.,the big mobile data collected by devices with various levels of mobility representing the movement and distribution of public and private agents in the *** especially focus on smart city situational awareness enabled by synthesizing the localization of hundreds of thousands of mobile software Apps using the Global Positioning System(GPS).This technique enjoys advantages such as a large penetration rate(∼50%urban population covered),uniform spatiotemporal coverage,and high localization *** first discuss the pragmatic requirements for smart city situational awareness and the challenges *** we introduce two suites of empowering technologies that help fulfill the requirements of(1)cybersecurity insurance for smart cities and(2)spatiotemporal modeling and visualization for situational awareness,both via big mobile *** main contributions of this review lie in the description of a comprehensive technological framework for smart city situational awareness and the demonstration of its feasibility via real-world applications.

关键词： Smart city Mobile data Situational awareness

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小盒商标纸在线压痕装置的设计与应用

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包装工程 2024年第5期45卷 151-156页

作者：李宇飞李建军卢良海李欢覃树良陈炎强彭品刘瑱广西中烟工业有限责任公司柳州卷烟厂广西柳州545006

目的解决中支双铝包小盒商标纸因模切压痕不稳定出现的烟包小盒侧边弹开翻折、烟包变形等问题。方法设计小盒商标纸在线压痕装置,该装置包括机架、传动轴、辗送轮、压痕件、导纸轮、对压轮、压痕避让部和托纸轮,同时开展正交试验,获取... 详细信息

目的解决中支双铝包小盒商标纸因模切压痕不稳定出现的烟包小盒侧边弹开翻折、烟包变形等问题。方法设计小盒商标纸在线压痕装置,该装置包括机架、传动轴、辗送轮、压痕件、导纸轮、对压轮、压痕避让部和托纸轮,同时开展正交试验,获取压痕件半径、刃缘弧长和包装机作业速度最佳参数组合。结果应用在线压痕装置后,小盒商标纸压痕挺度的平均绝对误差由6.0减小至1.9,次品烟包频率由37.6包/班次降低至8.4包/班次,改进后比改进前降低了77.7%。结论设计的小盒商标纸在线压痕装置可使商标纸挺度处于适宜水平,降低了该类缺陷烟包频率,提高了烟包包装质量。该技术可为提高双铝包包装机的产品质量、作业效率及稳定性提供支持。

关键词：小盒商标纸压痕装置包装机次品烟包压痕挺度

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皮疽诺卡菌导致中枢神经系统感染一例

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脑与神经疾病杂志 2024年第7期32卷 444-448页

作者：张亚楠张永亮赵萌郑立恒陈颜强河北省胸科医院石家庄050000 河北医科大学第二医院

目的分析河北省胸科医院神经内科收治的1例皮疽诺卡菌导致中枢神经系统感染患者的临床资料,为临床医师提供参考。方法本文报道1例由皮疽诺卡菌引起的脑脓肿病历,该患者早期主要表现为发热伴头痛,后期表现为意识障碍伴抽搐。患者先后曾住... 详细信息

目的分析河北省胸科医院神经内科收治的1例皮疽诺卡菌导致中枢神经系统感染患者的临床资料,为临床医师提供参考。方法本文报道1例由皮疽诺卡菌引起的脑脓肿病历,该患者早期主要表现为发热伴头痛,后期表现为意识障碍伴抽搐。患者先后曾住院3次,于2019年7月6日就诊于河北省胸科医院,通过脑脊液二代基因测序中发现病原体为皮疽诺卡菌,肺泡灌洗液培养发现诺卡菌,实施靶向复方磺胺甲噁唑治疗,症状未见缓解,后期合并了肺部念珠菌感染,并死于急性呼吸窘迫综合征。结果患者通过二代基因测序检测为诺卡菌,同时肺泡灌洗液发现该菌,并给予靶向抗生素治疗,后因急性呼吸窘迫症死亡。结论诺卡菌病临床表现无特异性,易被误诊。二代基因测序是一种无需培养的快速检测方法,可用于直接鉴定临床标本中的微生物;皮疽诺卡菌感染中枢神经系统的诊断以及鉴别诊断有更重要的意义。

关键词：皮疽诺卡菌中枢神经系统感染结核菌二代基因测序

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Thermo-Flow Performances for the Main-Auxiliary Integrated Natural Draft Dry Cooling System

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Journal of Thermal Science 2024年第3期33卷 1010-1025页

作者： ZHANG Zongyang HOU Yichen ZHOU Hanyu JIA He chen Lei KONG yanqiang WANG Weijia YANG Lijun DU Xiaoze Key Laboratory of Power Station Energy Transfer Conversion and System of Ministry of Education School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

Recently,natural draft dry cooling system with the main-auxiliary integrated air-cooled heat exchangers in the up and lower layers,has drawn attention to the electric power *** research firstly develops two physical models for the integrated cooling system,namely Case A and Case *** Case A,the main air-cooled heat exchanger is arranged in the upper layer and the auxiliary air-cooled heat exchanger arranged in the lower layer,while in Case B,the two heat exchanger systems are arranged in the opposite *** then,directing at the engineering TMCR and TRL 1 working conditions,the unit-local-overall thermo-flow characteristics of Case A and Case B are obtained and compared by numerical *** findings show that,for the auxiliary air-cooled exchanger,Case A has obviously higher cooling performances than Case B,with the difference varying from 5.46%to 7.55%.Whereas,for the main air-cooled exchanger,Case B shows the recovered cooling performances,with the difference changing from 1.15%to 2.99%.Case A is preferably recommended to the engineering application in consideration of more strict cooling demand of the auxiliary cooling ***,this research will provide some theoretical guidelines for the design and construction of the main-auxiliary integrated natural draft dry cooling system.

关键词： integrated dry cooling system main air-cooled heat exchanger auxiliary air-cooled heat exchanger upper layer and lower layer thermo-flow performances

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Spatiotemporal Changes of Hazard Intensity-Adjusted Population Exposure to Multiple Hazards in Tibet During 1982–2015

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International Journal of Disaster Risk Science 2018年第4期9卷 541-554页

作者： Anyu Zhang Jingai Wang Yao Jiang yanqiang chen Peijun Shi Key Laboratory of Environmental Evolution and Natural Disaster Ministry of EducationBeijing Normal UniversityBeijing 100875China Faculty of Geographical Science Beijing Normal UniversityBeijing 100875China Key Laboratory of Regional Geography Beijing Normal UniversityBeijing 100875China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijing 100875China Qinghai Normal University Xining 810008QinghaiChina

The dynamic changes of population exposure to hazards in high-altitude areas are an important factor in the scientific evaluation of environmental risks. In this study,the hazards of hypoxia, earthquakes, and snowstorms in Tibet were respectively described by the percentage of oxygen at sea level, earthquake intensity, and mean annual maximum snow depth. The rates of population affected by hypoxia, earthquakes, and snowstorms were calculated by chronic mountain sickness and historical disaster *** on these, the study examined the change in population exposure to the three hazards and their combinations by hazard intensity level at the 1 km 9 1 km grid scale in1982–2015. The results show that population exposures to hypoxia, earthquakes, and snowstorms were about 745 thousand, 97 thousand, and 168 thousand in 2015,respectively, among a total population in Tibet of 3.24 million. These exposures were mainly concentrated in the3400–5000 m above sea level zone. The population exposed to hypoxia and earthquakes showed a rising trend from 1982 to 2015, while the population exposed tosnowstorms decreased after 2000 due to reduced snowstorm intensity. Hypoxia-earthquake and hypoxia-snowstorm are the main multiple hazard combinations that people in Tibet suffered from and their personátime exposures were estimated at around 842 thousand and 913 thousand in 2015, respectively, with an average annual increase of 1.7% and 1.3%. Hypoxia is the most important health risk in Tibet. The areas of high personátime exposure to multiple hazards of hypoxia-earthquake-snowstorm are the key areas for strengthening integrated risk governance.

关键词： Earthquake High altitude Hypoxia Population exposure Snowstorm Tibet

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Progress on Space Medicine in 2008-2010

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空间科学学报 2010年第5期30卷 499-503页

作者： Li Yinghui Liu Zhaoxia Zhang Xiaoyou Bai yanqiang chen Shanguang China Astronaut Research and Training Center Beijing 100094 China

Space Medicine is a special subject to be rising with the development of manned *** China,Space Medicine has achieved great development during the past two *** this paper,the basic research of Space Medicine and its a... 详细信息

关键词：航天医学载人航天飞行基础研究中国

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材料参数对清水混凝土表观气孔控制的影响

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材料导报 2022年第S1期36卷 225-233页

作者：陈燕强钱春香张健东南大学材料科学与工程学院南京211189 东南大学绿色建材与固碳利用研究中心南京211189

材料参数是影响清水混凝土表观质量的重要因素。本工作采用不同种类的水泥、粉煤灰、粗细骨料和外加剂等组分研究了初始含气量、粗骨料最大粒径、塑性粘度系数、初始屈服应力和泌水率对清水混凝土表观气孔的影响,并分别给出了每种材料... 详细信息

材料参数是影响清水混凝土表观质量的重要因素。本工作采用不同种类的水泥、粉煤灰、粗细骨料和外加剂等组分研究了初始含气量、粗骨料最大粒径、塑性粘度系数、初始屈服应力和泌水率对清水混凝土表观气孔的影响,并分别给出了每种材料参数的适宜范围。此外,基于表面气孔面积率、气孔分布标准差和最大气孔直径三个参数提出了清水混凝土表观气孔评价标准。最后得出,将不同的材料参数调控至相应范围更易制备出表观质量优异的清水混凝土。

关键词：清水混凝土材料参数表观气孔评价标准

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