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Superconducting fluctuation induced conductance corrections near a pair-breaking quantum phase transition in doubly connected ultrathin cylinders of Al

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Science China(Physics,Mechanics & Astronomy) 2020年第3期63卷 89-97页

作者： Ke Zhang zongli wang Da Xu YaZhe wang H.wang Ying Liu Department of Physics Zhejiang UniversityHangzhou 310027China Key Laboratory of Artificial Structures and Quantum Control(MOE)and Shanghai Center for Complex Physics School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China Materials Research Institute and Department of Physics Pennsylvania State UniversityUniversity ParkPA 16802USA Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

We report measurements on ultrathin,doubly connected superconducting cylinders of Al that exhibit a destructive regime,which refers to the loss of superconductivity in a doubly connected superconductor near applied half flux quanta due to the sample topology and the small size of the sample.A depairing quantum phase transition(QPT)between a superconducting and metallic state tuned by the magnetic flux enclosed in the quasi one-dimensional(1D)cylinder was found at the onset of the destructive *** on magnetic flux and temperature dependent sample resistance as well as current-voltage characteristics revealed the presence of both thermally activated and quantum phase slips near the depairing *** the superconducting side of the QPT,thermally activated phase slips as described by the Langer-Ambegaokar and McCumber-Halperin(LAMH)theory were found to describe the sample resistance as the system was pushed towards the QPT by a magnetic field applied along the cylinder ***,deviation from this behavior was found at low temperatures,signaling the presence of the quantum phase *** importantly,we observed a highly unusual negative slope in the resistance versus temperature curves on the metallic side of the QPT as predicted by the diagrammatic calculation of the dc conductivities in a 1D system near a depairing *** work suggests that fluctuations from both the phase and the amplitude of the superconducting order parameter are important for the superconductor-to-metal depairing QPT.

关键词： mesoscopic superconductor quantum phase transition superconducting fluctuation

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Ultra-early treatment of bone marrow-derived mesenchymal stem cells for focal cerebral ischemia/ reperfusion injury

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Neural Regeneration Research 2010年第17期5卷 1296-1302页

作者： Hongjie Fan Weidong Yu zongli wang Qian wang Zhiyi He Department of Neurology Shengjing HospitalChina Medical UniversityShenyang 110004Liaoning ProvinceChina Department of Cadre Diagnosis and Treatment First Hospital of China Medical UniversityShenyang 110002Liaoning ProvinceChina Department of Neurology First Hospital of China Medical UniversityShenyang 110002Liaoning ProvinceChina

The time point at which bone marrow-derived mesenchymal stem cells（BMSCs）can be used in transplantation for the treatment of ischemic brain injury remains *** the present study,BMSCs were transplanted to the ischemic site 90 minutes *** results demonstrated that the transplanted BMSCs improved neurological function,reduced infarct volume,increased survivin expression,decreased caspase-3 expression and reduced *** suggests that BMSCs transplanted at an ultra-early stage ameliorated brain ischemia by increasing survivin expression,decreasing caspase-3 expression and reducing apoptosis at the ischemia/reperfusion injury site.

关键词： bone marrow-derived mesenchymal stem cells cerebral ischemia/reperfusion survivin caspase-3 cell apoptosis brain injury neural regeneration

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Monitoring the secretion from single cells with temporal and spatial resolution

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Chinese Science Bulletin 2000年第4期45卷 289-295页

作者： Weihua Huang Shen Hu Daiwen Pang zongli wang Jieke Cheng Wuhan Univ Analyt Sci Ctr Dept Chem & Environm Sci Wuhan 430072 Peoples R China

The secretion from cells plays a significant role in life activites and in the fields of neurobiology, cell biology, clinic, pathology, pharmacology ete. Thus to investigate the secretion at the single cell level with the developing methods is a frontiercross-discipline research activity. The contents, methods and new progress of this research have been reviewed by electrochemical monitoring combined with patch-clamp techniques, fluorescent detection and immunoassay, and the prospects on the frontier of the research area have been discussed.

关键词： single cell secretion neurotransmitters exocytosis electrochemical monitoring fluorescent method.

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Reliability of radiocarbon dating on various fractions of loess-soil sequence for Dadiwan section in the western Chinese Loess Plateau

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Frontiers of Earth Science 2014年第4期8卷 540-546页

作者： zongli wang Hui ZHAO Guanghui DONG Aifeng ZHOU Jianbao LIU Dongju ZHANG MOE Key Laboratory of West China's Environmental System Lanzhou University Lanzhou 730000 China Key Laboratory of Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The accurate radiocarbon dating of loess-soil sequences plays an essential role in the reconstruction of the environmental and climatic changes in continental settings during the last glaciation and Holocene. However, our knowledge about the reliability of radiocarbon ages of various fractions of soil and loess samples is still insufficient. Here, we present our study results on radio- carbon ages based on bulk organic matter, humin fraction, and carbonate of samples collected from a loess-paleosol section in the western Chinese Loess Plateau. We compare these observations with the optically stimulated luminescence ages and charcoal radiocarbon ages to evaluate the reliability of these fractions. We observed that the radio- carbon ages of humin fraction are very close to those of charcoal and are consistent with the optically stimulated luminescence ages within the experimental errors. We observed a significant deviation in the radiocarbon ages of carbonate and bulk organic matter from those of charcoal and optically stimulated luminescence ages, likely due to the dilution of these fractions during the pedogenetic process. Our results reveal that, except for charcoal, the humin fraction may yield reliable laC ages for the Chinese loess-soil sequence.

关键词： loess-soil sequence humin fraction charcoal,organic matter radiocarbon dating

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Amperometric Detection of Histamine and Amino Acid Neurotransmitters in Capillary Electrophoresis with Copper Microelectrodes

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Wuhan University Journal of Natural Sciences 1998年第3期3卷 87-90页

作者： Hu, Shen Huang, Weihua Pang, Daiwen wang, zongli Cheng, Jieke College of Chemistry Wuhan University Wuhan China

Copper microelectrodes were used in microvoltammetry to detect histamine and several amino acid neurotransmitters. High sensitivity was obtained through the use of copper microelectrodes, and detection limits of 50 nmol/L and 90 nmol/L were obtained for histamine and histidine, respectively. Furthermore, histamine and several amino acids neurotransmitters were firstly separated and detected by capillary electrophoresis with amperometric detection on copper microelectrodes. Mass limits of 490 amol and 440 amol were achieved for histamine and histidine, respectively, by using this mothod.

关键词： capillary electrophoresis amperometric detection copper microelectrode

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Humid Medieval Warm Period recorded by magnetic characteristics of sediments from Gonghai Lake, Shanxi, North China

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Chinese Science Bulletin 2011年第23期56卷 2464-2474页

作者： LIU JianBao CHEN FaHu CHEN JianHui XIA DunSheng XU QingHai wang zongli LI YueCong Key Laboratory of Western China's Environmental System (Ministry of Education) Lanzhou University Lanzhou 730000 China College of Resources and Environment Hebei Normal University Shijiazhuang 0500161 China

Variations in monsoon strength, moisture or precipitation in eastern China during the MWP reflected by different climatic records have shown apparent discrepancies. Here, detailed environmental magnetic investigations and mineralogical analyses were conducted on lacustrine sediments of Core GH09B1 (2.8 m long) from Gonghai Lake, Shanxi, North China, concerning the monsoon history during the MWP. The results demonstrate that the main magnetic mineral is magnetite. The sediments with relatively high magnetic mineral concentrations were characterized by relatively fine magnetic grain sizes, which were formed in a period of relatively strong pedogenesis and high precipitation. In contrast, the sediments with low magnetic mineral concentrations reflected an opposite process. The variations of magnetic parameters in Gonghai Lake sediments were mainly controlled by the degree of pedogenesis in the lake drainage basin, which further indicated the strength of the Asian summer monsoon. The variations in the and S 300 parameters of the core clearly reveal the Asian summer monsoon history over the last 1200 years in the study area, suggesting generally abundant precipitation and a strong summer monsoon during the Medieval Warm Period (MWP, AD 910–1220), which is supported by pollen evidence. Furthermore, this 3–6-year resolution environmental magnetic record indicates a dry event around AD 980–1050, interrupting the generally humid MWP. The summer monsoon evolution over the last millennium recorded by magnetic parameters in sediments from Gonghai Lake correlates well with historical documentation (North China) and speleothem oxygen isotopes (Wanxiang Cave), as well as precipitation modeling results (extratropical East Asia), which all indicate a generally humid MWP within which centennial-scale moisture variability existed. It is thus demonstrated that environmental magnetic parameters could be used as an effective proxy for monsoon climate variations in high-resolution lacustr

关键词：湖泊沉积物中世纪暖期磁性矿物中国北方潮湿特征记录山西季风强度

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Electrocatalysis of Metalloporphyrins(Ⅷ)——Electrocatalytic Reduction of Molecular Oxygen with Water-Soluble Cobalt (Ⅱ) Tetrakis(4-Trimethyl Ammonium Phenyl) Porphyrin Catalyst

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Chemical Research in Chinese Universities 1990年第2期6卷 102-109页

作者： wang zongli, Zhang Hui and Pang Daiwen (Department of Chemistry, Wuhan University , Wuhan)

Reported here is the electrocatalytic reduction of molecular oxygen in the presence of water-soluble cobalt(Ⅱ) tetrakis(4-trimethyl ammonium phenyl) porphyrin (Co(Ⅱ)TTAPP) as catalyst in solutions of various pH values. The overpotential of molecular oxygen reduction is reduced by ca. 200-400 mV in acidic and neutral solutions compared with several decades of millivolts in alkaline solutions, indicating that Co(Ⅱ)TTAPP possesses much higher catalytic activity in acidic and neutral solutions than in alkaline. H2TTAPP in solutions of various pH exhibits no significant catalytic activity for oxygen reduction. The significant difference in the electrocatalytic activity of Co(Ⅱ)TTAPP from that of H2TTAPP for oxygen reduction indicates that the electrocatalytic activity of Co(Ⅱ)TTAPP should be attributed to the central cobalt atom (Co(Ⅱ)) coordinated by N4 internal ring in Co(Ⅱ)TTAPP. The total number of electrons involved in oxygen reduction electrocatalyzed by Co (Ⅱ)TTAPP is 2, and the product of such reaction is H2O2 or HO2-in solutions of various pH. The reaction mechanism of oxygen reduction in acidic and alkaline solutions is also discussed.

关键词： Electrocatalysis Metalloporphyrins Electrocatalytic reduction

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Pollen-inferred vegetation and environmental changes since 16.7 ka BP at Balikun Lake, Xinjiang

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Chinese Science Bulletin 2010年第22期55卷 2449-2457页

作者： TAO ShiChen AN ChenBang CHEN FaHu TANG LingYu wang zongli LU YanBin LI ZhiFei ZHENG TongMing ZHAO JiaJu MOR Key Laboratory of West China's Environmental System Lanzhou University Lanzhou 730000 China Nanjing Institute of Geology and Paleontology Chinese Academy of Sciences Nanjing 210008 China

A high-resolution fossil pollen record from the sedimentary cores of Balikun Lake, northwestern China, combined with modern surface pollen data, is used to reconstruct the history of vegetation and climatic change since 16.7 cal. ka BP. Fossil pollen assem-blages and lithology indicate that the study area was dominated by desert. The desert had extremely arid climate and lower effec-tive moisture during 16.7–7.9 cal. ka BP, especially from 16.7 to 8.9 cal. ka BP when the lake maybe dried up. During 8.9–7.9 cal. ka BP, the environment gradually recovered in this area. It was then followed by the optimum period from 7.9 to 4.3 cal. Ka BP, when the effective moisture obviously increased. It was characterized by the typical desert-steppe/steppe vegetation and was ac-companied with several patch-birch woodlands around the lake. After that, a short but extremely arid climatic event occurred during 4.3–3.8 cal. ka BP, and the vegetation quickly changed from desert-steppe/steppe to desert. It was a relatively optimum period from 3.8 to 0.53 cal. ka BP showing typical desert-steppe/meadow-steppe landscape. Since 0.53 cal. ka BP, the climate has shown signs of deteriorating again. Furthermore, regional comparison shows that the characteristics of climatic and environmental evolution in this area were clearly different from East Asia monsoonal area during the last 16.7 cal. ka BP. It was characterized by the arid climate during the late-glacial and early Holocene, and relatively wet during the mid-late Holocene.

关键词：环境变化巴里坤湖花粉记录 BP 植被中晚全新世新疆气候变化

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Study on Composition of Inclusions in Minerals and Simulation Experiment on Hydrothermal Metasomatic Process of the Bayan Obo Iron Deposit

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Acta Geologica Sinica(English Edition) 1986年第4期60卷 43-55页

作者： Zeng Yishan, wang Fengzhen, He zongli, Liu Guoping, wang Chengqiang and Hao Jicheng Department of Geology, Peking University, Beijing Department of Geology Peking University Beijing

On the basis of the mechanism of formation of mineral inclusions, it may be assumed that a certain relation exists between the compositions of fluid inclusions in various minerals formed at the same stage of hydrothermal activity. In order to study the genetic relationships between different minerals in the Bayan Obo iron deposit, the compositions(K;, Na;, Ca;, Mg;, F;, Cl;, CO;, ΣSO;and pH) of inclusions in fluorite（23）, hematite（13）, magnetite（3）, sodium pyroxene（2） and dolomite（5） from the main mine and the eastern mine were determined by using the vacuum decrepitation and leaching methods, and cluster analyses of the data on the compostions were made. The Q-mode cluster analysis indicates that some iron oxide minerals in the deposit are related to dolomite of sedimentary origin, while others are related to fluorite and sodium pyroxene--products of hydrothermal activity. The R-mode cluster analysis shows that the components of the leaching solution may be divided into two groups: one includes CO;, Mg;and H;（pH）, which are obviously associated with dolomite; the other comprises Na;, K;, Ca;, F;, Cl;and SO;, which may possibly represent the composition of hydrothermal *** reaction of the Na-F-Cl solution（pH 4.72） with hematite dolomite at 300℃ and 5 × 10;Pa and under alternately"static and dynamic" conditions produced large amounts of hematite and fluorite and small amounts of smectite and Na（Fe） silicates, and the hematite-fluorite assemblage accords with the actual geological conditions in the deposit. From a comparison between the compositions of"static" and"dynamic" solution samples, it may be known that the flow reaction facilitates the migration of Fe, F, Ca and other components as well as Na-metasomatism（Na and Si are fixed in a solid phase）.The study of the compositions of mineral inclusions and simulation experiments on hydrothermal metasomatism have provided new evidence for the hypothesis of metamorphosed-sedimentary and hydrothermal-remoulding

关键词： Study on Composition of Inclusions in Minerals and Simulation Experiment on Hydrothermal Metasomatic Process of the Bayan Obo Iron Deposit

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新中国成立70年来现代化中国道路及其理论超越

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中国特色社会主义研究 2019年第4期 31-38页

作者：王宗礼西北师范大学马克思主义学院

中国实质意义上的现代化道路是从新中国成立后才开启的。70年来,中国的现代化道路经历了现代化道路的初创期、曲折探索期、形成发展期以及社会主义现代化强国新征程四个发展阶段。现代化中国道路既不是对西方现代化道路的简单模仿,也不... 详细信息

中国实质意义上的现代化道路是从新中国成立后才开启的。70年来,中国的现代化道路经历了现代化道路的初创期、曲折探索期、形成发展期以及社会主义现代化强国新征程四个发展阶段。现代化中国道路既不是对西方现代化道路的简单模仿,也不是对苏联东欧现代化模式的照抄照搬,更不是对东亚现代化道路的简单复制。它的基本规定性是:中国共产党的坚强领导和强有力的国家制度;现代化目标、民族复兴目标和理想社会目标的相互叠加;中国特色社会主义制度的制度基础;社会主义市场经济体制的突出优势以及改革开放的强大动力。现代化中国道路突破了西方现代化理论关于传统社会与现代社会二分法的理论,超越了西方现代化理论关于西方价值观念和文化是现代化的根本动因的理论,也是对西方政治发展理论、经济发展理论、人的现代化理论的超越和突破。

关键词：新中国成立70年现代化现代化中国道路社会主义现代化改革开放

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