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Linkage Between Winter Temperatures in the Yellow Sea and Atmospheric Circulation Indices

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Journal of Ocean University of China 2019年第2期18卷 261-270页

作者： YUAN Chengyi wei Hao LUO Xiaofan kuang Xiaodi College of Marine and Environmental Sciences Tianjin University of Science and Technology School of Marine Science and Technology Tianjin University National Marine Environmental Forecasting Center

This study investigated the linkage between winter temperature in the Yellow Sea(YS), China, and atmospheric indices and established this linkage through statistical models. The water temperature was obtained through hindcast simulation using a global–regional nested ocean model for the period of 1958–2007. The interannual variations of the simulated temperature were validated using satellite and in-situ observations. In the YS, the winter sea surface temperature(SST) had obvious interannual variations, with the maximum SST exceeding 2℃, and a significant shift from the cold to warm phase during 1988–1989. Based on the mechanism study, statistical models for the variations of water temperature in the YS were established using suitable atmospheric indices as predictors. For the northern YS(NYS) and the coastal region of the southern YS(SYS), statistical models of SST were established using linear regression based on the December–January–February mean Arctic oscillation index(AOI), representing the dominant large-scale atmospheric variability in boreal winter. For the YS warm current(YSWC) region, statistical models were established using both the AOI and the first principal component of the local wind stress curl(PC1-Curl), derived from the empirical orthogonal functions analysis. The PC1-Curl represents the influence of the local wind stress curl on the west-to-east shifts of the YSWC pathway. The applications proved that the models presented in this study have the ability to estimate winter temperatures in the YS within the recent years.

关键词： water temperature statistical model interannual variations atmospheric variability empirical orthogonal function analysis

Review of molar tooth structure research

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Journal of Palaeogeography 2014年第4期3卷 359-383页

作者： Hong-wei kuang Institute of Geology Chinese Academy of Geological Sciences

For more than a century, molar tooth structure （MTS） has been studied. The study developed in three stages. During the first stage （before 1980）, researchers described three basic morphologies of MTS, mainly from the Belt Supergroup in North America, and they provided several hypotheses for the origin of MTS. During the second stage （1980-1999）, the frequent discoveries of MTS on all continents resulted in many detailed descriptions of their shape and in several hypotheses concerning the origin of MTS. Notably, hypotheses of MTS＇s origin such as seismic activity and biological activity were developed. Since 2000, research has progressed into a new stage （the third stage）. This is due to discoveries of MTS in the Me- so-Neoproterozoic of China and elsewhere, and the ongoing debate on the seismic or biologi- cal origin is replaced by a hypothesis that involves gas expansion and chemically-controlled carbonate precipitation （both of them possibly affected by biological activities）. This latter idea has gradually been commonly recognized as the mainstream theory. Despite continued disa- greements, researchers now agree that microsparry calcite played a controlling role regarding the development and the global distribution of MTS in time and space during the Proterozoic, the morphological diversity, and the impact on the sedimentary environment. The present con- tribution analyses the three major hypotheses regarding the origin of MTS; it also discusses the shortcomings of the hypotheses regarding a seismic or biologic origin, and it details the modern hypothesis that links formation of cracks to the precipitation of sparry calcite. It is de- duced that important questions dealing with the Precambrian can be answered, among other aspects regarding the depositional palaeogeography and stratigraphic correlations.

关键词： molar tooth structure sparry calcite Precambrian

Catalytic recycling of plastics into value-added products

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Nano Research 2024年第11期17卷 9428-9445页

作者： Tianyu wei Pengcheng Zhou Wenxian Liu Xijun Liu Tairong kuang Functional Polymers and Advanced Materials (FPAM) Lab Zhejiang Key Laboratory of Plastic Modification and Processing Technology College of Materials Science and Engineering Zhejiang University of Technology Hangzhou 310014 China State Key Laboratory of Featured Metal Materials and Life-cycle Safety for Composite Structures Guangxi Key Laboratory of Processing for Nonferrous Metals and Featured Materials MOE Key Laboratory of New Processing Technology for Nonferrous Metals and Materials School of Resources Environment and Materials Guangxi University Nanning 530004 China

The overuse and ineffective management of plastics have led to significant environmental pollution. Catalytic upcycling into value-added chemicals has emerged as a promising solution. This review provides a comprehensive overview of recent advances in catalytic upcycling, focusing on the cleavage of chemical bonds such as carbon-carbon (C-C), carbon-oxygen (C-O), and carbon-hydrogen (C-H) in plastics. It systematically discusses plastics conversion via electrocatalysis, thermal catalysis, and photocatalysis. Additionally, it explores the conversion of plastics into value-added chemicals and functional polymers. The review also addresses the challenges in this field and aims to offer insights for developing sustainable and effective plastics upcycling technologies.

关键词： plastics recycling catalysis chemical recycling value-added chemicals functional polymers

Extraction and separation of heavy rare earths from chloride medium byα-aminophosphonic acid HEHAPP

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Journal of Rare Earths 2018年第3期36卷 304-310页

作者： Shengting kuang Zhifeng Zhang Yanling Li Haiqin wei Wuping Liao State Key Laboratory of Rare Earth Resource Utilization ERCfor the Separation and Purification of REs and ThoriumChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China University of Science and Technology of China Hefei 230026China

The extraction and separation of heavy rare earths（REs） using newly synthesized a-aminophosphonic acid extractant 2-ethylhexyl-3-（2-ethylhexylamino）pentan-3-yl phosphonic acid（HEHAPP, HA） in nheptane were investigated from chloride medium. The extraction stoichiometries of lanthanum, gadolinium, yttrium and lutetium are determined to be REA3 by the slope analysis method. The favorable separation factors of adjacent heavy REs（Ⅲ）,i.e. β（Y/Ho）, β（Er/Y）,β（Tm/Er）,β（Yb/Tm） and β（Lu/Yb）, are determined to be1.87,1.36, 3.21,3.22 and 1.93, respectively, when extracted from a binary system at proper condition. The loading capacities of HA for Ho, Er, Yb and Lu increase in the order Ho 〈 Er 〈 Yb 〈 Lu with the values being 0.201, 0.205, 0.216 and 0.229 mol/L, respectively. So HA would be a potential extractant for the separation of heavy REs（Ⅲ）. Among inorganic acids such as H2 SO4, HNO3 and HCl, HCl is tested to be the most effective stripping agent.

关键词： Heavy rare earths α-aminophosphonic acid Solvent extraction Separation

Assessing gray matter volume in patients with idiopathic rapid eye movement sleep behavior disorder

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Neural Regeneration Research 2019年第5期14卷 868-875页

作者： Xian-Hua Han Xiu-Ming Li wei-Jun Tang Huan Yu Ping Wu Jing-Jie Ge Jian Wang chuan-Tao Zuo kuang-Yu Shi PET Center Huashan Hospital Fudan University Department of Radiology Huashan Hospital Fudan University Department of Neurology Huashan Hospital Fudan University Department of Nuclear Medicine Technical University Munich

Idiopathic rapid eye movement sleep behavior disorder(iRBD) is often a precursor to neurodegenerative disease. However, voxel-based morphological studies evaluating structural abnormalities in the brains of iRBD patients are relatively rare. This study aimed to explore cerebral structural alterations using magnetic resonance imaging and to determine their association with clinical parameters in iRBD patients. Brain structural T1-weighted MRI scans were acquired from 19 polysomnogram-confirmed iRBD patients(male:female 16:3; mean age 66.6 ± 7.0 years) and 20 age-matched healthy controls(male:female 5:15; mean age 63.7 ± 5.9 years). Gray matter volume(GMV) data were analyzed based on Statistical Parametric Mapping 8, using a voxel-based morphometry method and two-sample t-test and multiple regression analysis. Compared with controls, iRBD patients had increased GMV in the middle temporal gyrus and cerebellar posterior lobe, but decreased GMV in the Rolandic operculum, postcentral gyrus, insular lobe, cingulate gyrus, precuneus, rectus gyrus, and superior frontal gyrus. iRBD duration was positively correlated with GMV in the precuneus, cuneus, superior parietal gyrus, postcentral gyrus, posterior cingulate gyrus, hippocampus, lingual gyrus, middle occipital gyrus, middle temporal gyrus, and cerebellum posterior lobe. Furthermore, phasic chin electromyographic activity was positively correlated with GMV in the hippocampus, precuneus, fusiform gyrus, precentral gyrus, superior frontal gyrus, cuneus, inferior parietal lobule, angular gyrus, superior parietal gyrus, paracentral lobule, and cerebellar posterior lobe. There were no significant negative correlations of brain GMV with disease duration or electromyographic activity in iRBD patients. These findings expand the spectrum of known gray matter modifications in iRBD patients and provide evidence of a correlation between brain dysfunction and clinical manifestations in such patients. The protocol was approved by the Et

关键词： nerve regeneration idiopathic rapid eye movement sleep behavior disorder synucleinopathies magnetic resonance imaging gray matter volume statistic parametric mapping voxel-based morphometry structure Parkinson’s disease neurodegenerative diseases neural regeneration

Hydrothermal Synthesis,Crystal Structure and Electrochemical Properties of the Copper(II) Complex [Cu_4O_4(phen)_4(ClC_6H_4COO)_2(H_2O)_2]·(H_2O)_3

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Chinese Journal of Structural Chemistry 2006年第11期25卷 1331-1336页

作者： LI wei LI Chang-Hong YANG Ying-Qun kuang Yun-Fei Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China Department of Chemical Engineering Hunan Institute of Technology Hengyang 421008 China

The title complex of copper（Ⅱ） with m-chlorobenzoic acid, 1,10-phenanthroline （phen） and copper perchlorate has been synthesized and characterized in the solvent mixture of water and methanol. Crystal data for this complex： triclinic, space group PI^-, a = 1.06853（12）, b = 1.30740（16）, c = 1.49546（17） nm, α= 101.791（2）,β = 103.413（2）, γ = 105.815（2）°, V= 1.8736（4） nm^3, Mr = 904.67, Dc = 1.604 g/cm^3, Z = 2,/7（000） = 924,μ = 1.34 mm^-1, GOOF = 1.049, the final R = 0.0324 and wR = 0.0797. The structure analysis shows that a chair-like structure [Cu4O4] is defined by three quadrilaterals shaped by four copper and four oxygen atoms, and every copper ion is coordinated by three oxygen atoms from three wate： molecules and two nitrogen atoms from one 1,10-phenanthroline molecule, giving a distorted square-pyramidal coordination geometry. The CV analysis results indicate that the electron transfer in the electrode reaction is quasi-reversible.

关键词： copper(Ⅱ) complex hydrothermal synthesis electrochemical property

Anti-parity-time symmetry hidden in a damping linear resonator

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Science China(Physics,Mechanics & Astronomy) 2023年第10期66卷 22-32页

作者： Xun-wei Xu Jie-Qiao Liao Hui Jing Le-Man kuang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China

Phase transition from the over-damping to under-damping states is a ubiquitous phenomenon in physical systems. However, what kind of symmetry is broken associated with this phase transition remains unclear. Here, we discover that this phase transition is determined by an anti-parity-time(anti-PT) symmetry hidden in a single damping linear resonator, which is significantly different from the conventional anti-PT-symmetric systems with two or more modes. We show that the breaking of the anti-PT symmetry yields the phase transition from the over-damping to under-damping states, with an exceptional point(EP) corresponding to the critical-damping state. Moreover, we propose an optomechanical scheme to show this anti-PT symmetry breaking by using the optical spring effect in a quadratic optomechanical system. We also suggest an optomechanical sensor with the sensitivity enhanced significantly around the EPs for the anti-PT symmetry breaking. Our work unveils the anti-PT symmetry hidden in damping oscillations and hence opens up new possibilities for exploiting wide anti-PT symmetry applications in single damping linear resonators.

关键词： anti-parity-time symmetry exceptional points damping linear resonator optomechanics

Hydrothermal Synthesis and Electrochemical Properties of Complex Cu(CH_3C_6H_4COOH)_2(2,2′-bipy)·(H_2O)

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Chinese Journal of Structural Chemistry 2006年第5期25卷 616-620页

作者： LI wei LI Chang-Hong YANG Ying-Qun kuang Dai-Zhi XU wei-Jian Department of Chemistry and Materials Science Hengyang Normal University Hengyang 421008 China Department of Chemical Engineering Hunan Institute of Technology Hengyang 421008 China College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China

The title complex has been synthesized by 4-methylbenzoic acid and 2,2′-bipyridine （bipy） in the mixed solvent of water and methanol. It crystallizes in the triclinic system, space group P1^- with a = 0.7047（3）, b = 1.1217（5）, c = 1.6718（7） nm, α = 103.826（7）, β = 90.772（6）, γ = 104.195（6）°, C26H25CuN2O5.50, Mr = 517.02, V = 1.2404（9） nm^3, Dc = 1.384 g/cm^3, Z = 2, F（000） = 536,μ（MoKα） = 0.921 mm^-1, R = 0.0782 and wR = 0.2172. Structural analysis shows that the copper atom is coordinated with three oxygen atoms from two 4-methylbenzoic acids and one water molecule together with two nitrogen atoms from 2,2＇-bipyridine, giving a distorted square-pyramid coordination geometry. The cyclic voltametric behavior of the complex has also been described.

关键词： copper(Ⅱ) complex hydrothermal synthesis electrochemical property

Laboratory investigation on hydraulic fracture propagation in sandstone-mudstone-shale layers

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Petroleum Science 2022年第4期19卷 1664-1673页

作者： Jiang-chuan He kuang-Sheng Zhang Han-Bin Liu Mei-Rong Tang Xue-Lin Zheng Guang-Qing Zhang PetroChina Changqing Oilfield Company Xi′an710018ShaanxiChina College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China

During the stimulating unconventional reservoirs, the vertical propagation of hydraulic fractures is crucial for enlarging the stimulated reservoir volume, especially in multi-layers of sandstone, mudstone and shale(sand-mud-shale). To investigate the effects of lithological interface and fracturing fluid viscosity on the fracture propagation vertically in the multi-layers, hydraulic fracturing experiments in laboratory were performed on the outcrop samples of 30 cm × 30 cm × 30 cm collected from Yanchang Formation in Ordos Basin. The results show that hydraulic fractures are multi-branched and zig-zagged when they initiate in shale, simple when they commence in sandstone or mudstone. Hydraulic fractures created with low-viscosity fracturing fluid can only cross sandstone from mudstone, but those induced by high-viscosity fracturing fluid can cross the sand-mud-shale layers. Furthermore, the high-viscosity fracturing fluid reduces the fractures complexity in shale, facilitating vertical fracture propagation. The injection pressure fluctuates slightly as the hydraulic fracture extends from shale to sandstone or mudstone, otherwise it fluctuates significantly. From the laboratory investigation, a hydraulic fracturing scheme for Chang 7 Member was proposed, with its feasibility proved in field tests.

关键词： Sandstone-mudstone-shale Multi-layers Hydraulic fracturing experiments Lithological interface