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Geomorphic features of Quaternary glaciation in the Taniantaweng Mountain, on the southeastern Qinghai-Tibet Plateau

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Journal of Mountain Science 2019年第2期16卷 256-274页

作者： ZHANG Wei CHAI Le IAN S.Evans LIU Liang LI Ya-peng QIAO Jing-ru tang qian-yu SUN Bo College of Urban and Environmental Sciences Liaoning Normal University Geography Department Durham University

We present geomorphological evidence for multiple glacial fluctuations during the Quaternary in the Taniantaweng Mountain, which is situated at the transition zone of the southeastern Qinghai-Tibet Plateau and the yunnan-Guizhou Plateau. To reconstruct the history of glacial evolution during the Quaternary Glaciation, we present a ~13000 km^2 geomorphologic map(1:440,000) for the Quaternary glaciations, as well as three electron spin resonance(ESR) ages and three optically stimulated luminescence(OSL) ages from the landforms. By integrating these with ages from previous studies, four major glacial advances are identified during marine oxygen isotope stages(MIS) 6, 3, 2 and 1. This glacial chronology is in reasonable agreement with existing glacial chronologies from other parts of the Hengduan Mountains and surrounding mountains. Glaciers had extended to the yuqu River during the glacial maximum advance(MIS 6), but became successively more restricted from MIS 3 to MIS 1. The glacial distribution show that precipitation brought by the south Asian monsoon might play a primary role in driving glacial advances during the last glacial period in the southeastern Qinghai-Tibet Plateau.

关键词： Qinghai-Tibet Plateau Taniantaweng Mountain Glacial landform ESR dating OSL dating South Asian monsoon

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成都青羊区背街小巷行道树孢粉致敏风险分析

应用生态学报 2022年第6期33卷 1615-1621页

作者：唐雨倩吴晓奕宗桦西南交通大学建筑学院风景园林系成都610031

为研究背街小巷行道树的孢粉致敏风险,以成都市青羊区410条背街小巷为例,在记录背街小巷行道树特征的基础上,计算其孢粉致敏风险指数(I_(UGZA))并叠加区域人口密度图,获得青羊区背街小巷的孢粉致敏风险地图。结果表明:410条背街小巷共... 详细信息

为研究背街小巷行道树的孢粉致敏风险,以成都市青羊区410条背街小巷为例,在记录背街小巷行道树特征的基础上,计算其孢粉致敏风险指数(I_(UGZA))并叠加区域人口密度图,获得青羊区背街小巷的孢粉致敏风险地图。结果表明:410条背街小巷共有行道树32461棵,属27科、41属、52种。树种分布严重不均,过度使用小叶榕(占比31.8%)、银杏(12.9%)和香樟(8.5%)。背街小巷的I_(UGZA)均值为2.61,致敏风险较高,春季为首要风险季。其中,175条背街小巷的致敏程度低(I_(UGZA)为0~1),174条致敏程度相对较低(I_(UGZA)为1~5),6条致敏风险极高(I_(UGZA)为15~20)。相关性分析显示,背街小巷平均树高和树冠与街道面积比是影响其I_(UGZA)的关键因素。叠加人口密度图后显示,青羊区行道树孢粉致敏风险较高的街区主要是少城街道、草市街道、西御河街道、府南街道和苏坡街道片区。

关键词：背街小巷行道树孢粉致敏城市绿地致敏指数

Discovery of a new family member of arsenic–vanadium polyoxometalates with high catalytic performance for one-pot coupling of CO2, epoxides and amines

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Tungsten 2025年第1期7卷 80-87页

作者： Fang-qian Wang Yin Zhang Wei-Wei Wang Mei-qian Fu Hong-Bing Mo Wei-Dong yu Chao Liu Jun Yan College of Chemistry and Chemical Engineering Central South University Junior Education Department Changsha Normal University School of Science Hunan University of Technology and Business

Arsenic-vanadium polyoxometalates（POMs） represent a family of tremendous potential catalysts owing to their peculiar physical and chemical *** in CO2conversion,using POMs to catalyze the conversion of CO2and epoxide into chemical intermediates is the research ***,A new family number of arsenic-vanadium POMs,[N（CH3）4]4[As8V12O38（H2O）]·2H2O({As8V12O38}),was reported and characterized by single-crystal X-ray diffraction,fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,*** from other allotropicity,{As8V12O38}shows a different structure pattern with an I-43d *** obtained {As8V12O38} was employed as a catalyst for the *** initial catalytic reaction confirmed that {As8V12O38} can catalyze the formation of epoxy carbonate by using 1.01 kPa CO2and epoxide at 70℃.Furtherly,when added amine in the catalytic system,oxazolidinone could be obtained by high yields,which provides an efficient way to convert CO2into profitable ***,a possible catalytic reaction mechanism was proposed by using different characterization analyses.{As8V12O38} first catalyzes the epoxide and CO2to form an epoxy carbonate and then catalyzes epoxy carbonate and benzylamine into oxazolidinone.

关键词： Arsenic CO2 conversion Oxazolidinone Polyoxometalates Vanadium

Recent progress in exploring heterogeneous catalyst surface chemistry with near ambient pressure XPS

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Science China Chemistry 2025年

作者： yuanjie Xu Zemin An yu tang Institute of Molecular Engineering Plus Institute of Molecule Catalysis and In Situ/Operando Studies College of Chemistry Fuzhou University

X-ray photoelectron spectroscopy(XPS) is a crucial surface analysis technique that has become a key tool in the study of heterogeneous catalysis. Detecting surface chemistry under conditions that closely mimic actual industrial catalytic processes is essential for understanding the mechanisms involved. In the past decade, near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) has been increasingly utilized to study the surface chemistry of catalysts during heterogeneous catalytic processes, offering insights into structure-performance correlations. This review begins with a brief overview of NAP-XPS instrumentation. Next, we discuss the application of NAP-XPS in the study of thermal catalysis reactions, followed by a summary of the research on catalyst restructuring under reaction conditions. Additionally, we address the challenges and future perspectives for the development and application of NAP-XPS. Catalysis is inherently dynamic, requiring an understanding of the real-time behavior of catalysts under varying conditions. Therefore, future improvements in the ability to probe reaction intermediates with higher spatial and temporal resolution under conditions that closely mimic industrial environments are needed.

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Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries

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Nano-Micro Letters 2025年第1期17卷 176-190页

作者： Xiaohong Zou qian Lu Mingcong tang Jie Wu Kouer Zhang Wenzhi Li yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Jiangsu Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and TechnologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Department of Chemistry The Chinese University of Hong KongMa Lin BuildingShatinHong Kong SAR 999077People’s Republic of China WA School of Mines:Minerals Energy and Chemical Engineering(WASM‑MECE)Curtin UniversityPerthWA 6102Australia Research Institute for Advanced Manufacturing The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China Research Institute for Smart Energy The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong SARPeople’s Republic of China

Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe *** is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe *** the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts.

关键词： Catalyst-support interaction Supported catalysts Heterointerface Oxygen evolution reaction Zn-air batteries

Vector meson's spin alignments in high energy reactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 5-20页

作者： Jin-Hui Chen Zuo-tang Liang yu-Gang Ma Xin-Li Sheng Qun Wang Key Laboratory of Nuclear Physics and Ion-beam Application (MoE) Institute of Modern PhysicsFudan University Institute of Frontier and Interdisciplinary Science Key Laboratory of Particle Physics and Particle Irradiation (MOE)Shandong University INFN-Firenze Department of Modern Physics University of Science and Technology of China School of Mechanics and Physics Anhui University of Science and Technology

The global spin alignment of vector mesons has been observed by the STAR collaboration at the Relativistic Heavy Ion Collider （RHIC） at Brookhaven National Laboratory （BNL）.It provides a unique opportunity to probe the correlation between the polarized quark and antiquark in the strongly coupled quark-gluon plasma （sQGP） produced in relativistic heavy ion collisions,opening a new window to explore the properties of s *** addition,spin alignments of vector mesons have also been observed in other high-energy particle collisions such as e+e-annihilations at high energies where hadron production is dominated by quark fragmentation *** results obtained are quite different from those obtained in heavy ion collisions where quark coalescence/combination mechanism dominates suggesting strong dependence on hadronization *** comprehensive studies in different hadronization processes are *** this article,we present a brief review of theoretical and experimental advances in the study of vector meson’s spin alignments in a variety of high-energy particle collisions,with emphasis on hadronization mechanisms.

关键词： vector meson spin alignment global polarization relativistic heavy ion collisions fragmentation

温度梯度区域熔化作用下熔池迁移的元胞自动机模拟

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物理学报 2019年第4期68卷 279-288页

作者：方辉薛桦汤倩玉张庆宇潘诗琰朱鸣芳江苏省先进金属材料高技术研究重点实验室东南大学材料科学与工程学院南京211189 南京理工大学材料科学与工程学院南京210094

本文采用耦合凝固和熔化效应的二维元胞自动机(cellular automaton, CA)模型,对温度梯度区域熔化(temperature gradient zone melting, TGZM)效应引起的熔池在固液两相区中的迁移现象进行模拟研究.模拟分析了抽拉速度、熔池初始位置、... 详细信息

本文采用耦合凝固和熔化效应的二维元胞自动机(cellular automaton, CA)模型,对温度梯度区域熔化(temperature gradient zone melting, TGZM)效应引起的熔池在固液两相区中的迁移现象进行模拟研究.模拟分析了抽拉速度、熔池初始位置、温度梯度和合金成分等因素对TGZM动力学的影响,并将模拟结果与解析模型的预测结果进行比较验证.通过模拟发现,在温度梯度作用下,熔池总是向着高温方向迁移;当抽拉速度低于或高于临界抽拉速度时,熔池朝向移动的液相线或固相线迁移;对于给定的抽拉速度,位于糊状区内临界位置以上的熔池会迁移进入液相,而位于临界位置以下的熔池会逐步靠近固相线.此外,温度梯度越高,合金成分越低,熔池的迁移速度越快.

关键词：定向凝固温度梯度区域熔化熔池迁移元胞自动机

Multicomponent polymerization of elemental sulfur,difluoromethylene phosphobetaine and aryl silyl ethers toward aromatic poly(O,O′-monothiocarbonate)s

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Science China Chemistry 2025年

作者： Yongjiang yu Rongrong Hu Ben Zhong tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular Aggregates South China University of Technology School of Science and Engineering Shenzhen Institute of Aggregate Science and Technology The Chinese University of Hong Kong AIE Institute

Polythiocarbonates with similar structures to polycarbonates, have emerged as a group of promising sulfur-containing polymers with a range of practical applications, taking advantages of their excellent optical properties, good thermal stability and filmforming ability, and so on. However, the synthesis of polythiocarbonates generally suffered from mixed isomeric structures of repeating units, and hazardous sulfur-containing reagents. In this work, an efficient multicomponent reaction of elemental sulfur,difluoromethylene phosphobetaine（PDFA）, and aryl silyl ethers was designed with the assistance of organic base 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene（MTBD） to produce 12 kinds of O,O′-monothiocarbonate compounds in up to 93% yields,taking advantages of the unique chemical property of difluorocarbene, and the deprotection of silyl group by F-generated from PDFA. Most importantly, the MTBD-assisted multicomponent polymerization of bis（aryl silyl ether）s, elemental sulfur, and PDFA was developed, affording 12 kinds of poly（O,O′-monothiocarbonate）s with well-defined structures, high Mws of up to16900 g/mol and high yields（up to 99%）. These poly（O,O′-monothiocarbonate）s possessed good film-forming properties and thermal stability, high light refractive indices and transmittance. The facile synthesis of these polymonothiocarbonates might pave the way for the development of promising sulfur-containing polymer materials.

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可降解玉米赤霉烯酮的重组过氧化物酶A4-Prx的纯化与活性研究

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现代食品科技 2015年第8期31卷 65-70页

作者：钟凤吴晖刘思利唐语谦华南理工大学轻工与食品学院广东广州510640

以来源于不动杆菌Acinetobacter ***04的过氧化物酶A4-Prx的毕赤酵母工程表达菌株GS115/p PIC9K-A4-Prx为研究对象,从培养液中纯化重组过氧化物酶A4-Prx,分析其ZEA降解活力,并研究过氧化物酶A4-Prx的酶学特性。本论文首先研究了蛋白的... 详细信息

以来源于不动杆菌Acinetobacter ***04的过氧化物酶A4-Prx的毕赤酵母工程表达菌株GS115/p PIC9K-A4-Prx为研究对象,从培养液中纯化重组过氧化物酶A4-Prx,分析其ZEA降解活力,并研究过氧化物酶A4-Prx的酶学特性。本论文首先研究了蛋白的纯化方法,通过一系列分离纯化手段得到纯的过氧化物酶A4-Prx,最终纯化倍数约为12,HPLC实验结果表明纯化后的过氧化物酶A4-Prx具有ZEA降解能力,且ZEA降解率达到63%。对过氧化物酶A4-Prx进行酶学特性研究,结果表明,p H和温度均对A4-Prx的过氧化物酶酶活有显著影响,p H 9.0和反应温度60℃时酶活最高,A4-Prx的最大酶活是204.1 U,此时过氧化氢浓度为9.7 m M。A4-Prx过氧化物酶反应受EDTA的抑制作用明显。本研究为过氧化物酶的酶学研究奠定了基础,为后续的A4-Prx降解机理研究提供先决条件,推动生物降解ZEA研究的进展。

关键词：过氧化物酶玉米赤霉烯酮毕赤酵母酶学特性