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Degradation of warm permafrost and talik formation on the Qinghai-Tibet Plateau in 2006-2021

Advances in Climate Change Research 2024年第2期15卷 275-284页

作者： Qi-Hang MEI Ji CHEN You-Qian LIU Shou-Hong ZHANG Jing-Yi ZHAO Tian-Chun DONG jun-cheng WANG Yao-jun ZHAO Beiluhe Observation and Research Station of Frozen Soil Engineering and Environment Key Laboratory of Cryospheric Science and Frozen Soil EngineeringNorthwest Institute of Eco-Environmental and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co.Ltd Xining 810007China University of Chinese Academy of Sciences Beijing 100049China

Permafrost is degrading globally,particularly those with low thermal stability on the Qinghai-Tibet Plateau,owing to climate ***,the inadequacy of direct research on permafrost degradation based on in-situ monitoring limits the prediction of permafrost degradation and engineering *** study explored the processes and modes of permafrost degradation into talik by analyzing ground temperature data from five points in the hinterland of the Qinghai-Tibet Plateau from 2006 to *** results showed that the degradation of the warm permafrost layer with a geothermal gradient of zero occurred simultaneously in the top and bottom *** rate of permafrost degradation from the top down and bottom up increase during the degradation process,but the increase of the former is more drastic after the formation of thawed ***,the construction of the Qinghai-Tibet Railway changed the degradation modes of the permafrost in adjacent natural sites through horizontal heat transfer,particularly after through talik formation under the *** findings suggest that taking countermeasures before or immediately after forming thawed interlayer is more *** evaluating the thermal impact of projects in warm permafrost regions,special attention should be given to the horizontal heat transfer process that may result from the formation of a through talik.

关键词： Warm permafrost Degradation Talik Qinghai-Tibet Plateau Climate change

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Tracing the provenance of aeolian loess in the Yangtze River Delta through zircon U–Pb age and geochemical investigations

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Journal of Mountain Science 2018年第4期15卷 708-721页

作者： QIAN Peng ZHENG Xiang-min cheng jun HAN Yu-jie DONG Yan ZHANG Jian-guo School of Geography Nantong University Department of Geography East China Normal University School of Geosciences University of South Florida

Given the conflicts over the proposed formation mechanisms of Xiashu loess, the question of the provenance of sediments comprising the Xiashu loess in the Yangtze River Delta has not been satisfactorily resolved. In this study, the provenance of aeolian sediments of the Yangtze River Delta, China was examined by applying the detrial zircon U–Pb dating technique, Sr–Nd isotopic and trace element compositional analysis. U-Pb dating analysis was conducted on the Xiashu loess at three locations over the Yangtze River Delta, including Huangnishan(HNS) hill, Shengshan(SS) island and the Xuancheng(XC) area. The Xiashu loess and the sediments of the Yangtze River Valley share considerable similarity in their zircon U-Pb age spectra with the same main age peak and comparable age distribution. By contrast, significant differences in the age spectra, existbetween the Xiashu loess and loess deposits of Chinese Loess Plateau(CLP). Coarse grains of the Yangtze River Delta loess may have a proximal material source identical to the sediments from the Yangtze River valley. Sr–Nd isotopic values of the Xiashu loess match those from the northern margin of the Tibetan Plateau. Rare earth element ratios independent of grain size illustrate that the values from loess of the Yangtze River Delta mostly overlap with those of CLP loess. This feature implies that loess from the Yangtze River Delta has a dominant source of distant material similar as the CLP loess. As such, we conclude that multi-proxy analysis of sediments can shed new light on tracing the provenance of aeolian loess in the Yangtze River Delta.

关键词： Aeolian loess Provenance tracing Zircon U-Pb age Geochemistry Yangtze River Delta

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Detrital apatite fission track constraints on Cenozoic tectonic evolution of the northeastern Qinghai-Tibet Plateau, China： Evidence from Cenozoic strata in Lulehe section, Northern Qaidam Basin

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Journal of Mountain Science 2018年第3期15卷 532-547页

作者： DU Ding-ding ZHANG cheng-jun MUGHAL Muhammad Saleem WANG Xiao-yu BLAISE Dembele GAO jun-ping MA Yuan LUO Xin-rong School of Earth Sciences and Mineral Resources Lanzhou University Lanzhou 730000 China Key Laboratory of Western China's Mineral Resources of Gansu Prouince Lanzhou 730000 China Institute of Geology University of Azad Jammu and Kashmir Muzaffarabad 13100 Pakistan

The Northern Qaidam Basin is located at the northeastern part of the Qinghai-Tibetan Plateau. It contains very thick Cenozoic terrestrial clastic sediments, which records the formation of the northern Qaidam Basin due to compressional deformation during the Indo-Asian collision. In this paper, we used detrital apatite fission-track thermochronology, including 4 sandstones and 2 conglomerates samples from the Lulehe section, to reveal the Cenozoic evolution of the northern Qaidam Basin. Fission-track dating indicated the source region of the Lulehe section has experiencedimportant cooling and uplifting in the Late Cretaceous(at ~85.1 Ma and ~65 Ma) and the Eocene(~52 Ma), respectively. The AFT age distribution on the section suggested that the provenance of Lulehe section sediments were mainly derived from the south Qilian Shan(Qilian Mountains) and Altun Shan(Altun Mountains), and two significantly provenance changes may occur at 43.4-46.1 Ma and ~37.8 Ma, respectively. The results may have strong constrains on the Cenozoic deformation and tectonic evolution of the northern Qaidam Basin and Qinghai-Tibet Plateau.

关键词： Northern Qaidam Basin Apatite Fission-Track Tectonic evolution Provenance analysis

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Form transition of sodium during combustion of black liquor coal slurry

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Journal of China University of Mining and Technology 2008年第1期18卷 6-12页

作者： LAN Ze-quan CAO Xin-yu ZHOU jun-hu LIU Jian-zhong2, cheng jun CEN Ke-fa North China Institute of Science and Technology Yanjiao Hebei 065201 China State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou Zhejiang 31.0027 China

Several typical ash samples from a 0.25 MW test furnace fired black liquor coal slurry were selected for investigation. The phases and compounds containing sodium in ash samples were acquired from X-ray diffraction analyses. As well, detailed analyses of the amounts of major mineral elements along thickness gradients of representative ash samples were carried out. The elements, including Na, Si, A1, S and C1 were analyzed by the advanced electron probe microanalyzer equipment, which provid evidence and interpretation for the analytical results of XRD. The findings indicate that the occurrence form of sodium has experi- enced important changes during the combustion of black liquor coal slurry, which translated into nepheline, thenardite, sodium sulfate, sodium chloride, sodium silicoaluminate, hanyne and other phases containing sodium, from NaOH, Na2CO3 and Na2S in raw fuel. Of all the sodium compounds, nepheline, thenardite and sodium sulfate are the most important forms of Na in solid com- bustion residues. Such a transformation of Na during the combustion of black liquor coal slurry resulted in a considerable impact on ash deposition and is not only different from the raw coal and papermaldng black liquors, but is also affected by local circum- stances in the combustion furnace. Amounts of Na, S and C1 in ash deposits from low temperature zones were larger than those from high temperature zones. Our findings should provide important theoretical instructions for industrial applications of black liquor coal slurry.

关键词： black liquor coal slurry sodium form transition ash deposition

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Cp_2ZrCl_2-catalyzed synthesis of 2-aminovinyl benzimidazoles under microwave conditions

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Chinese Chemical Letters 2015年第3期26卷 297-300页

作者： Qi Sun cheng-jun Wang Shan-Shan Gong Yong-Jian Ai Hong-Bin Sun Jiangxi Key Laboratory of Organic Chemistry Jiangxi Science and Technology Normal University Department of Chemistry Northeastern University

A microwave-assisted general method for the synthesis of 2-aminovinyl benzimidazoles has been *** of the 1,2-phenylenediamines and N-arylated/N,N-dialkylated 3-aminoacroleins with bis（cyclopentadienyl）zirconium（IV） dichloride（Cp2Zr Cl2） as the catalyst under microwave irradiation for 3–5 min followed by in situ Mn O2 oxidation afforded thirteen 2-aminovinyl benzimidazoles in good yields.

关键词： microwave irradiation catalyzed heating spectrometer sized ethanol silica equiv facile

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Integrated Chinese and Western Medicine in Treatment of Bronchopleural Fistula with Mycobacterium abscessus:A Case Report

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Chinese Journal of Integrative Medicine 2024年第8期30卷 742-746页

作者： WANG Qian-yun cheng Miao BAN cheng-jun ZHANG Li-shan WANG Hong-wu YANG Bing ZOU Heng WANG Ming-zhe The First Clinical Medical College of Beijing University of Chinese Medicine Beijing100700China Department of Respiratory Dongzhimen HospitalBeijing University of Chinese MedicineBeijing100700China

Bronchopleural fistula(BPF)is defined as a pathological connection between the trachea or bronchus and the pleural *** may occur as a serious complication after lung surgery.^((1))It has a low incidence of 1%-3%^((2.3... 详细信息

关键词： pleural lung surgery

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Model evidence for climatic impact of thermohaline circulation on China at the century scale

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Chinese Science Bulletin 2010年第27期55卷 3215-3221页

作者： cheng jun LIU ZhengYu HE Feng GUO PinWen CHEN ZhongXiao OTTO-BLIESNER Bette Key Laboratory of Meteorological Disaster of Ministry of Education College of Atmospheric Sciences Nanjing University of Information Science and Technology Nanjing 210044 China Center for Climatic Research & Department Atmospheric and Oceanic Sciences University of Wisconsin-Madison Madison WI53706 USA Climate and Global Dynamics Division National Center for Atmospheric Research Boulder CO 80307-3000 USA

Based on transient simulation of the last deglaciation(significant global warming period)using a fully coupled model and sensitivity experiment,we show explicitly how the thermohaline circulation(THC)affects the climate of China,especially during periods of abrupt climate *** simulated evolution of the Chinese climate was consistent with the paleoclimate record during the last *** example,the whole Chinese region warmed significantly during the BФlling-AllerФd warming event(BA).When the magnitude of the THC was reduced in the sensitivity experiment during BA,warming of the Chinese region was greatly *** work shows that in addition to orbital forcing and greenhouse gases,the THC is an important factor influencing climate change in China at the century scale.

关键词：中国地区气候突变温盐环流耦合模型敏感性试验末次冰消期证据古气候记录

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Genome-wide identification and characterization of long non-coding RNAs in Tribolium castaneum

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Insect Science 2021年第5期28卷 1262-1276页

作者： Liu Yang You-Wei Wang Yao-Yao Lu Bin Li Ke-Ping Chen cheng-jun Li School of Life Sciences Jiangsu UniversityZhenjiangJiangsu Province 212013China Jiangsu Key Laboratory for Biodiversity and Biotechnology College of Life SciencesNanjing Normal UniversityNanjing210023China

Long non-coding RNAs(lncRNAs)are poorly understood in *** this study,we performed genome-wide analysis of lncRNAs in Tribolium castaneum by *** total,4516 lncRNA transcripts corresponding to 3917 genes were identified from late embryos,early larvae,late larvae,early pupae,late pupae and early adults of ***,including 3152 novel lncRNAs and 1364 known *** lncRNAs have few exons and transcripts,and are short in *** development,they exhibited nine different expression ***,they can act either by targeting messenger RNAs(1813 lncRNAs)and lncRNAs(45 lncRNAs)or as micro RNA(miRNA)precursors(46 lncRNAs).LncRNAs were observed to target the metabolic enzymes of glycolysis,TCA cycle and amino acids,demonstrating that lncRNAs control metabolism by regulating metabolic ***,lncRNAs were shown to participate in cell differentiation and development via their *** miRNA precursors,lncRNAs could participate in the ecdysone signaling *** study provides comprehensive information for lncRNAs of ***,and will promote functional analysis and target identification of lncRNAs in the insect.

关键词： glycolysis lncRNA metabolism TCA cycle Tribolium castaneum

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Unified neutron star EOSs and neutron star structures in RMF models

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Communications in Theoretical Physics 2022年第9期74卷 105-119页

作者： cheng-jun Xia Toshiki Maruyama Ang Li Bao Yuan Sun Wen-Hui Long Ying-Xun Zhang Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China School of Information Science and Engineering NingboTech UniversityNingbo 315100China Advanced Science Research Center Japan Atomic Energy AgencyShirakata 2-4TokaiIbaraki 319-1195Japan Department of Astronomy Xiamen UniversityXiamen 361005China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Frontiers Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China China Institute of Atomic Energy Beijing 102413China Guangxi Key Laboratory Breeding Base of Nuclear Physics and Technology Guilin 541004China

In the framework of the Thomas-Fermi approximation,we systematically study the EOSs and microscopic structures of neutron star matter in a vast density range with n_(b)≈10^(-10)-2 fm^(-3),where various covariant density functionals are adopted,i.e.,those with nonlinear self couplings(NL3,PK1,TM1,GM1,MTVTC)and density-dependent couplings(DD-LZ1,DDME-X,PKDD,DDME2,DD2,TW99).It is found that the EOSs generally coincide with each other at nb■10^(-4)fm^(-3)and 0.1 fm^(-3)■n_(b)■0.3 fm^(-3),while in other density regions they are sensitive to the effective interactions between *** adopting functionals with a larger slope of symmetry energy L,the curvature parameter K_(sym)and neutron drip density generally increases,while the droplet size,proton number of nucleus,core-crust transition density,and onset density of non-spherical nuclei,*** functionals predict neutron stars with maximum masses exceeding the two-solar-mass limit,while those of DD2,DD-LZ1,DD-ME2,and DDME-X predict optimum neutron star radii according to the observational ***,the corresponding skewness coefficients J are much larger than expected,while only the functionals MTVTC and TW99 meet the start-of-art constraints on *** accurate measurements on the radius of PSR J0740+6620 and the maximum mass of neutron stars are thus essential to identify the functional that satisfies all constraints from nuclear physics and astrophysical *** linear correlations between neutron stars’radii at M=1.4M⊙and 2M⊙,the slope L and curvature parameter K_(sym)of symmetry energy are observed as well,which are mainly attributed to the curvature-slope correlations in the functionals adopted *** results presented here are applicable for investigations of the structures and evolutions of compact stars in a unified manner.

关键词： neutron star EOS nuclear pasta covariant density functionals

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Minimally invasive thoracoscopic left atrial appendage occlusion compared with transcatheter left atrial appendage closure for stroke prevention in recurrent nonvalvular atrial fibrillation patients after radiofrequency ablation:a prospective cohort study

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Journal of Geriatric Cardiology 2021年第11期18卷 877-885页

作者： Jian-Long WANG Kuo ZHOU Zheng QIN Wan-jun cheng Ling-Zhi ZHANG Yu-Jie ZHOU Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijingChina Interventional Department Luanzhou People’s HospitalTangshanChina Department of Cardiology Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of Heart Lung and Blood Vessel DiseaseBeijing Key Laboratory of Precision Medicine of Coronary Atherosclerot1ic DiseaseClinical Center for Coronary Heart DiseaseBeijingChina

BACKGROUND Tanscatheter left atrial appendage(LAA)closure and minimally invasive thoracoscopic LAA occlusion are local interventions of LAA for stroke prevention in patients with nonvalvular atrial fibrillation(NVAF).However,the safety and efficacy of these methods have not been *** prospective cohort study aimed to assess the safety and efficacy of those two treatment approaches for stroke prevention in NVAF *** Two hundred and nine recurrent NVAF patients who received radiofrequency ablation were *** pa-tients were treated with transcatheter LAA closure or thoracoscopic LAA *** patients were followed up from the first postoperative day and evaluated for efficacy endpoints(stroke/transient ischemic attack(TIA),systemic embolism(SE),and death)and a safety endpoint(bleeding events).Perioperative complications were *** After a median follow-up of 1.8 years(383 patient-years),the overall rate of the composite efficacy endpoints was similar between the two groups(3.8 vs.2.7 events per 100 patient-years;HR=0.71;95%CI:0.225−2.237;P=0.559).However,regarding primary safety endpoint,there were 1.5 bleeding events per 100 patient-years in the thoracoscopic LAA occlusion group,com-pared with 6.4 in transcatheter LAA closure group(HR=0.246;95%CI:0.074−0.819;P=0.022).The incidence of operative com-plications was 3/138(2.17%)in thoracoscopic LAA occlusion group and 1/71(1.41%)in transcatheter LAA closure *** Thoracoscopic LAA occlusion and transcatheter LAA closure have similar efficacy in preventing stroke in NVAF ***,the thoracoscopic group had fewer bleeding events than the transcatheter group,but the former group required a longer hospital stay.

关键词： prevention patients transcatheter

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