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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 warming.The 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 lacking.Here,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 Station.Using seasonal differences and statistical methods,we calculated the relative contribution rates of vegetation to changes in atmospheric oxygen concentration.Our 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 differences.Vegetation significantly impacts the oxygen concentration,with a contribution rate of 16.7%–24.5%,which is underestimated in existing research.Our findings provide important insights into the factors that influence atmospheric oxygen concentration and highlight the contribution of vegetation.To 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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Geomorphology-oriented theoretical framework and construction method for value-added DEM

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Journal of Geographical Sciences 2024年第1期34卷 165-184页

作者： ZHANG haiping tang Guoan XIONG Liyang YANG Xin LI Fayuan Key Laboratory of Virtual Geographic Environment Ministry of EducationNanjing Normal UniversityNanjing 210023China School of Geography Nanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Digital elevation model(DEM)plays a fundamental role in the study of the earth system by expressing surface configuration,understanding surface process,and revealing surface mechanism.DEM is widely used in analysis and modeling in the field of geoscience.However,traditional DEM has the defect of single attribute,which is difficult to support the research in earth system science oriented to geoscience process and mechanism mining.Hence,realizing the value-added data model on the basis of traditional DEM is necessary to serve digital elevation modeling and terrain analysis under the background of a new geomorphology research paradigm and earth observation technology.A theoretical framework for value-added DEM that mainly includes concept,connotation,content,and categories,is constructed in this study.The relationship between different types of value-added DEMs as well as the research significance and application category of this theoretical framework are also proposed.The following are different methods of value-added DEMs:(1)value-added methods of DEM space and time dimensions that emphasize the integration of the ground and underground as well as coupling of time and space,(2)attribute-based value-added methods composed of material(including underground,surface,and ground)and morphological properties,and(3)value-added methods of features and physical elements that consider geographical objects and landform features formed by natural processes and artificial effects.The digital terrace,slope,and watershed models are used as examples to illustrate application scenarios of the three kinds of value-added methods.This study aims to improve expression methods of DEMs under the background of new surveying and mapping technologies by adding value to the DEM at three levels of dimensions,attributes,and elements as well as support knowledge-driven digital geomorphological analysis in the era of big data.

关键词： spatial data model value-added DEM digital terrain analysis geomorphological ontology geomorphology

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Construction of a Metallacyclopentadiene Ring through the Attack of Carbanions to M≡C Bond Followed by C—H Activation

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Chinese Journal of Chemistry 2024年第3期42卷 235-242页

作者： Chun tang Shengjie Zhang Zhengyu Lu Qian Li Ming Luo Dafa Chen haiping Xia State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringCollaborative Innovation Center of Chemistry for Energy MaterialsXiamen UniversityXiamenFujian361005 China Shenzhen Grubbs Institute and Guangdong Provincial Key Laboratory of Catalysis Department of ChemistrySouthern University of Science and TechnologyShenzhenGuangdong518055 China

Metallacyclopentadienes are important metallacycles and regarded as intermediates in many reactions,therefore,new methods to achieve them are anticipated.In this study,a formal[3+2]method,through the reactions of an osmapentalyne with benzyl carbanions,was developed.The reactions underwent a nucleophilic attack of carbanions to the Os≡C bond,followed by C—H activation to form the five-membered osmacyclopentadiene ring.Most of the reactions were carried out at room temperature,the substituents on the aromatic rings of benzyl carbanions are diverse,and the resulting products contain an Os—H bond,representing a novel type of 10C-carbolong complexes.This work provides a new convenient route to construct metallacyclopentadienes,which is expected to further promote the development of such a type of substances.

关键词： Metallacyclopentadiene Carbolong chemistry Osmium C–H activation Nucleophilic addition

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青藏高原典型地区近地表大气氧含量及其影响因素

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地理教学 2024年第10期 4-6页

作者：刘冬唐海萍北京师范大学地理科学学部北京100875

在广泛的地理空间尺度上,海拔是影响青藏高原近地表大气氧含量的主要因素。近期研究表明,海拔与氧含量的关系在青藏高原典型地区有较大差异。本文利用典型地段调查法,研究了青藏高原六个典型区海拔、气候和植被因子与近地表氧含量关系... 详细信息

在广泛的地理空间尺度上,海拔是影响青藏高原近地表大气氧含量的主要因素。近期研究表明,海拔与氧含量的关系在青藏高原典型地区有较大差异。本文利用典型地段调查法,研究了青藏高原六个典型区海拔、气候和植被因子与近地表氧含量关系的地域性特征。在所研究的变量中,海拔、植被净初级生产力、植被盖度、植被生长季长度、气温和降水是预测氧气含量的重要变量。海拔与氧含量在不同典型区的关系表现为负相关或无相关性。与青藏高原区域的整体研究相比,典型地段调查强调了植被是海拔以外影响近地表氧含量的重要因素,而非气候条件。

关键词：近地表氧含量典型地区青藏高原海拔

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Driving mechanisms of desertification process in the Horqin Sandy Land—a case study in Zhalute Banner,Inner Mongolia of China

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Frontiers of Environmental Science & Engineering 2008年第4期2卷 487-493页

作者： haiping tang Yufu CHEN Xinyu LI College of Resources Science and Technology Key Laboratory of Environmental Change and Natural Disaster of the Ministry of EducationBeijing Normal UniversityBeijing 100875China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of SciencesBeijing 100101China Institute of Beijing Landscape Gardening Beijing 100102China

Both natural and human factors contributing to desertification were examined to understand the driving mechanisms of the desertification process in Zhalute Banner,Inner Mongolia of China.The coefficient of variation(CV)and climate departure index(Z)were calculated to examine the fluctuations and trends of interannual variations of temperature and precipitation;TM remote sensing data was extracted to obtain the sandy land area;linear regression analysis was used to analyze climate changes and the socio-economic evolution over the years,and it was also used to standardize the variables,which included annual temperature,annual precipitation,human population,and livestock number,in order to measure the difference in the rate of change between climate and anthropogenic factors.The results showed that there was a rise of about 1.6uC in temperature but no significant change in precipitation from 1961 to 2000,which indicated a short-term climatic trend toward aridity in this area,a condition necessary for desertification.The fraction of precipitation in spring tended to increase whilst the fraction in autumn and winter decreased.Both the human population and livestock population had tripled and the cultivated area had doubled from 1961 to 2000,suggesting that socio-economic factors might have contributed more significantly to the desertification.Between 1988 and 1997,the sandy land area increased by 12.5%,nearly 2.4 times in the farming section.It could be concluded that the driving mechanisms of the desertification processes in Zhalute banner are mainly the policy of cropland expansion and the rising populations of humans and their livestock,which has affected the land use pattern in the past decades.

关键词： climatic change potential evapo-transpiration(PE) human activities land use change

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Overexpression of SIRT3 disrupts mitochondrial proteostasis and cell cycle progression

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Protein & Cell 2016年第4期7卷 295-299页

作者： Xiaofei Wang haiping tang Yuling Chen Binghuan Chi Shiyu Wang Yang Lv Di WU Renshan Ge Haiteng Deng MOE Key Laboratory of Bioinformatics School of Life Sciences Tsinghua University Beijing 100084 China Wenzhou Medical College Wenzhou 325035 China Center of Nephrology The General Hospital of the PLA Beijing 100853 China

Dear Editor, As a mitochondrial deacetylase, SIRT3 deacetylates many enzymes involved in central metabolism and maintains mitochondrial proteostasis （Verdin et al., 2010; Papa and Germain, 2014）. Substrates of SIRT3 include components of the respiratory complexes, proteins involved in fatty acid oxidation and TCA cycle （Yu et al., 2012）. SIRT3 activates MnSOD to maintain reactive oxygen species （ROS） home- ostasis and a loss of SIRT3 contributes to the age-associ- ated diseases （McDonnell et al., 2015; Qiu et al., 2010）. SIRT3 plays dual roles functioning as a tumor suppressor or a promoter in tumorigenesis and progression （Alhazzazi et al., 2011 ）. On one hand, SIRT3 regulates the cellular ROS level and maintains genomic stability, and mediates meta- bolic reprogramming to prevent tumorigenesis （Finley and Haigis, 2012）. As a result, the low expression of SIRT3 has been found in breast cancer, glioblastoma, colon cancer, osteosarcoma, prostate, and ovarian cancers （Kim et al., 2010; Finley and Haigis, 2012）. On the other hand, SIRT3 is a prosurvival factor that modulates p53 activities and is upregulated in oral cancer, the node-positive breast cancer, and bladder cancer （Ashraf et al., 2006; Alhazzazi et al., 2011）. These results suggest that SIRT3 possesses the tumor-type dependent function and its precise role needs to be elucidated in the context of a specific cancer. Clear cell renal cell carcinoma （ccRCC） is the most common histo- logical subtype of renal cancer （Cohen and McGovern, 2005）. The aims of the present study were to examine the expression of SIRT3 in ccRCC and to characterize effects of SIRT3 on tumorigenesis and progression using 293T human embryonic kidney cells as the model system that has cancer stem cell-like features （Debeb et al., 2010）.

关键词： Respiratory Complex 293T Human Embryonic Kidney SIRT3 Overexpression Cellular Reactive Oxygen Species Level 293T Human Embryonic Kidney Cell

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在役环境磁场对L360管线钢及焊接接头腐蚀行为的影响

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中国腐蚀与防护学报 2024年第2期44卷 471-479页

作者：邓志彬胡枭刘应彦岳航张千汤海平鲁锐中国民用航空飞行学院民航安全工程学院广汉618307 民机火灾科学与安全工程四川省重点实验室广汉618307 中国民用航空飞行学院航空油料管理处广汉618307 中国石油天然气股份有限公司云南销售分公司昆明650000

为明确磁场对L360输油管道腐蚀行为的影响,通过电化学测试及腐蚀形貌观察等手段,研究了L360管线钢母材及其焊接接头在不同强度磁场作用下3.5%NaCl溶液中的腐蚀行为。结果表明:随着磁场强度的增大,L360管线钢母材及其焊接接头的电荷转移... 详细信息

为明确磁场对L360输油管道腐蚀行为的影响,通过电化学测试及腐蚀形貌观察等手段,研究了L360管线钢母材及其焊接接头在不同强度磁场作用下3.5%NaCl溶液中的腐蚀行为。结果表明:随着磁场强度的增大,L360管线钢母材及其焊接接头的电荷转移电阻先增大后减小,腐蚀电流密度先减小后增大,较低强度磁场(60 mT)抑制了腐蚀,而较高强度磁场(120 mT)加速了腐蚀。相同磁场强度下,焊接接头腐蚀速率大于母材。机理分析表明:磁场作用力诱导金属离子吸附于电极界面,形成腐蚀产物膜阻碍腐蚀进行;高强度磁场作用下,Lorentz力能够破坏腐蚀产物膜,加速离子扩散,进而加速金属腐蚀。

关键词：磁场 L360 管线钢焊接接头 3.5%NaCl溶液腐蚀行为

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陆相混合细粒岩沉积微相及其对甜点的控制作用——以吉木萨尔凹陷芦草沟组为例

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沉积学报 2024年第3期42卷 839-856页

作者：朱柏宇印森林郭海平唐攀赵俊威陈旭雷章树长江大学录井技术与工程研究院湖北荆州434023 中国石化江汉油田分公司工程院武汉430100 中国石油新疆油田公司新疆克拉玛依834000 长江大学地球科学学院武汉430100

【目的】吉木萨尔凹陷二叠系芦草沟组发育了一套陆相混积沉积体系,混积细粒岩沉积微相类型及甜点储层分布规律等研究的不足制约了该区页岩油高效开发。【方法】综合岩心、露头、测井、X射线荧光光谱(X-Ray Fluorescence,XRF)元素录井、... 详细信息

【目的】吉木萨尔凹陷二叠系芦草沟组发育了一套陆相混积沉积体系,混积细粒岩沉积微相类型及甜点储层分布规律等研究的不足制约了该区页岩油高效开发。【方法】综合岩心、露头、测井、X射线荧光光谱(X-Ray Fluorescence,XRF)元素录井、分析化验和试油试采等资料,采用岩相构型、沉积微相耦合分析和动静结合等方法,开展了沉积微环境及微相类型划分、沉积模式及其对甜点的控制作用等研究。【结果】(1)研究区主要发育浪成交错层理、水平层理、同生变形构造、黄铁矿、方解石条带、鸟眼构造和结核、缝合线构造、含生物化石和白云岩溶蚀孔8类沉积构造。研究区分为半深湖—深湖、混合浅湖和碎屑浅湖亚相,细分为半深湖泥、云坪、混合滩坝、混合浅湖泥、浅湖砂坝和碎屑浅湖泥等6种微相,不同微相沉积特征及其沉积机制差异明显。(2)建立了咸化湖泊相混积细粒岩沉积微相模式。芦一段自下而上从深湖—半深湖—浅湖演化过程,发育了浅湖砂坝、混合滩坝与云坪微相。其中,云坪呈连片状大范围分布,混合滩坝呈土豆状分布,发育程度较高,不同层规模有差异,浅湖砂坝发育程度一般,呈断续状局限分布,垂向上呈薄储集层与厚层泥岩叠置状。芦二段以浅湖为主,微相类型与芦一段类似,但形态、规模与叠置样式差异较大。云坪和混合滩坝发育数量和规模大大减小,浅湖砂坝则发育程度较高,呈大规模分散土豆状发育,垂向上呈厚层叠置状。不同位置剖面微相的叠置样式不同。(3)甜点段XRF元素分析显示,目的层沉积时为干燥炎热的半咸水环境到咸水过渡环境,古生产力水平较高;下甜点段为富氧环境,上甜点段则为厌氧亚还原到还原环境。(4)沉积微相控制了甜点分布和开发对策。混合滩坝微相Ⅰ类甜点发育程度高,非均质性弱,开发效果最好,采用大规模部署水平井平台化作业进行效益开发。云坪微相Ⅲ类甜点发育,非均质性强,开发效果一般,是后续接替区域。浅湖砂坝Ⅱ类甜点发育,整体分散状,连续性较差,非均质性强,开发效果较好。【结论】后续应在沉积微相空间分布精细研究基础上,参考核磁曲线参数部署水平井开发。

关键词：细粒沉积岩混合浅湖沉积微相页岩油芦草沟组吉木萨尔凹陷

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木质素催化氢解制备高附加值化学品研究进展

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燃料化学学报（中英文） 2024年第7期52卷 945-958页

作者：刘菊平唐紫玥陈应泉王贤华陈汉平杨扬杨海平华中科技大学能源与动力工程学院煤燃烧与低碳利用全国重点实验室湖北武汉 430074

开发和利用可再生生物质资源是实现二氧化碳减排的有效途径.而生物质结构复杂,整体反应性和利用率较低.木质素是自然界中唯一具有高能量密度的可再生芳香族聚合物,其转化和利用在全球范围内引起了广泛关注.然而,木质素结构的复杂性、连... 详细信息

开发和利用可再生生物质资源是实现二氧化碳减排的有效途径.而生物质结构复杂,整体反应性和利用率较低.木质素是自然界中唯一具有高能量密度的可再生芳香族聚合物,其转化和利用在全球范围内引起了广泛关注.然而,木质素结构的复杂性、连接方式的不确定性、侧链连接的稳定性以及反应片段不可避免的再缩合,使得将木质素解聚成生物燃料或芳香化学品成为一项艰巨的挑战.催化氢解技术可将木质素转化为高选择性、高收率的酚类单体.但是木质素催化解聚过程中化学键的定向剪切,产物与结构之间的转化机理仍不清晰.本工作针对木质素的催化氢解生产高值化学品的最新研究进展,重点总结了木质素的催化氢解过程中催化剂及其高值化学品产物间的耦合关联,着重讨论了不同催化剂体系对木质素解聚产物过程机理的影响,尤其对于金属基催化剂,综述了贵金属基催化剂、过渡基金属催化剂、水滑石催化剂和金属有机框架催化剂对于产物分布影响的最新进展,并进一步总结了不同催化剂存在的问题和转化机制;同时木质素加氢催化裂解过程中溶剂是促进木质素溶解、加速传热传质、促进反应物和催化剂在反应器中均匀分散的关键.本工作并对木质素液化的主要溶剂,例如水、醇类和新型溶剂体系对木质素的解聚效应进行综述.最后,就领域所面临的机遇和挑战进行了总结和展望,为木质素高效定向转化与高值化利用提供了理论参考.

关键词：木质素催化氢解化学品

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嵌合抗原受体T细胞序贯异基因造血干细胞移植治疗Ph样急性淋巴细胞白血病21例的疗效及安全性

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中华血液学杂志 2024年第1期45卷 35-40页

作者：戴海萍沈宏杰李正崔巍崔庆亚郦梦云陈思帆朱明清吴德沛唐晓文苏州大学附属第一医院血液内科国家血液系统疾病临床医学研究中心江苏省血液研究所血液学协同创新中心苏州大学造血干细胞移植研究所苏州215006

目的评估嵌合抗原受体T细胞(CAR-T细胞)序贯异基因造血干细胞移植(allo-HSCT)治疗Ph样急性淋巴细胞白血病(Ph样ALL)患者的疗效及安全性。方法纳入2018年3月至2023年8月在苏州大学附属第一医院接受CAR-T细胞序贯allo-HSCT治疗的21例Ph样... 详细信息

目的评估嵌合抗原受体T细胞(CAR-T细胞)序贯异基因造血干细胞移植(allo-HSCT)治疗Ph样急性淋巴细胞白血病(Ph样ALL)患者的疗效及安全性。方法纳入2018年3月至2023年8月在苏州大学附属第一医院接受CAR-T细胞序贯allo-HSCT治疗的21例Ph样ALL患者,对其临床资料进行回顾性分析。结果21例患者中,男14例,女7例。接受CAR-T细胞治疗时的中位年龄为22(6~50)岁。7例为ABL1样重排,14例为JAK-STAT重排。接受CAR-T细胞治疗前,12例为血液学未缓解,7例为多参数流式细胞术微小残留病(MFC-MRD)阳性,2例为MFC-MRD阴性。CAR-T细胞均来自患者自体淋巴细胞。9例接受CD19 CAR-T细胞治疗,12例接受CD19/CD22双靶点CAR-T细胞治疗。CAR-T细胞治疗后28 d评估,完全缓解率为95.2%,其中MFC-MRD阴性缓解率75.0%。19例患者出现0~2级细胞因子释放综合征(CRS),2例患者出现3级CRS,经治疗后均恢复。所有患者CAR-T细胞治疗后均接受allo-HSCT。CAR-T细胞治疗后桥接移植的中位时间为63(38~114)d。5例患者CAR-T细胞治疗后出现复发,4例为血液学复发,1例为分子学复发。ABL1组和JAK-STAT组患者的3年总生存率分别为(83.3±15.2)%和(66.6±17.2)%,3年无复发生存率分别为(50.0±20.4)%和(55.6±15.4)%,差异均无统计学意义(P值均>0.05)。结论CAR-T细胞桥接allo-HSCT,能使大部分Ph样ALL患者迅速达到深度缓解,显著延长患者的无白血病生存。

关键词：嵌合抗原受体T细胞异基因造血干细胞移植 Ph样白血病淋巴细胞急性

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