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Global significance of the carbon cycle in the karst dynamic system:evidence from geological and ecological processes

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China Geology 2018年第1期1卷 17-27页

作者： jian-hua Cao Xia Wu Fen huang Bill hu Chris Groves hui Yang Chun-lai Zhang Institute of Karst Geology CAGSKarst Dynamics LaboratoryMNRGuilin 541004China International Research Center on Karst UNESCOGuilin 541004China National Center for International Research of Karst Dynamic System and Global Change Guilin 541004China Florida State University TallahasseeFL 32395USA Western Kentucky University Bowling GreenKY42101USA

On the basis of proposing the existence of a karst carbon cycle and carbon sink at a watershed scale,this paper provides four pieces of evidence for;the integration of geology and ecology during the carbon cycle processes m the karst dynamic system,and estxmated the karst carbon sink effect using the methods of comparative monitoring of paired watersheds and the carbon stable isotope tracer *** results of the soil carbon cycle in Maocun,Guilin,showed that the soil carbon cycle in the karst area,the weathering and dissolution of carbonate rocks under the soil,resulted in a lower soil respiration of 25% in the karstoarea than in a non-karst area (sandstone and shale),and the carbon isotope results indicated that 13.46% of the heavy carbon of the hmestone is involved in the soil carbon *** comparative monitoring results m paxred watersheds,suggesting that the HCO3 concentration m a karst spring is 10 times that of a rivulet in a non-karst area,while the concentration of inorganic carbon flux is 23.8 *** both chemical stoichiometry and carbon stable isotopes,the proportion of carbon in karst springs derived from carbonate rocks was found to be 58.52% and 37.65% *** comparison on carbon exchange and isotopes at the water-gas interface between the granite and carbonate rock basins in the Li River showed that the CO2 emission of the karst water is 10.92 times that of the allogenic water from the non-karst area,while the carbon isotope of HCO3^- in karst water is lighter by 8.62%.However,this does not mean that the karst water body has a larger carbon source *** the contrary,it means the karst water body has a greater karst carbon sink *** the karst subterranean stream in Zhaidi,Guilin,is exposed at the surface,carbon-rich karst water stimulated the growth of aquatic *** values of carbon stable isotopes in the same species of submerged plants gradually becomes heavier and heavier,and the 512 m flow process has a maxim

关键词： Karst carbon cycle Carbon stable isotope Carbon sink effect Submerged plants Guilin

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NUMERICAL SIMULATION AND ANALYSIS ON THE HEMODYNAMICS OF AN ELASTIC ANEURYSM

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Journal of Hydrodynamics 2008年第2期20卷 216-224页

作者： ZHAO jun-wei YIN Wen-yi DING Guang-hong YANG Xin-jian SHI Wan-chao ZHANG Xiao-long Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China Beijing Institute ofNeurosurgery Beijing 100050 China huashan Hospital Affiliated to Fudan University Shanghai 200040 China

Intracranial aneurysms are pathological dilatations which endanger people＇s health. Hemodynamics is thought to be an important factor in the pathogenesis and treatment of aneurysms. To date, the bulk of investigations into hemodynamics have been conducted by making use of mathematically idealized models for rigid aneurysms and associated arteries. However the walls of aneurysms and associated arteries are elastic in vivo. This study shows the differences of the simulation between elastic and rigid wall models. The numerical simulation of elastic aneurysm model is made fi＇om a representative Digital Subtraction Angiography （DSA） image and calculated with CFD software to get the wall deformation and the velocity field. Then the results are analyzed. By comparing the simulation results of the two models from their velocity vectors and shear stress distribution, many differences can be noted. The main difference exists in the distribution of velocity magnitude at some sections, with one outlet having obviously off-center distribution for the elastic wall model. The currents of the distribution of wall shear stress along the wall of aneurysm simulated in rigid and elastic wall models were similar. But there were apparent differences between the two models on the values of wall shear stress especially at the neck of aneurysm. The off-center distribution of velocity magnitude affects the distribution of wall shear stress and the exchange of substance through the wall. The analysis demonstrated clearly that the results of 2-D elastic numerical simulation were in good agreement with the clinical and pathological practice. The results of this study play an important role in the formation, growth, rupture and prognosis of an aneurysm on clinic application.

关键词： aneurysm 2-D numerical simulation elastic wall medical image

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Effect of heat treatment on microstructure,mechanical and tribological properties of in-situ (TiC+TiB)/TC4 composites by casting

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China Foundry 2023年第3期20卷 207-217页

作者： Bo-wen Zheng Shuai Chen Chun-yu Yue Xue-jian Lin Fu-yu Dong Hong-jun huang Xiao-jiao Zuo Yin-xiao Wang Xiao-guang Yuan School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China

To enhance the performance of in-situ synthesized 6vol.%(Ti C+Ti B)/TC4 titanium matrix composites fabricated by casting,a variety of heat treatment processes were carried *** conducting microstructure observations following various heat treatments,it was found that the composites exhibit a basketweave microstructure,consisting of an α phase and a transformed β *** sizes of(α+β) phases were found to be refined to varying degrees after the heat treatment processes,while the morphology of Ti B remains largely unchanged and Ti C becomes *** testing revealed that all composites subjected to different heat treatments demonstrate a notable increase in ultimate compressive strength as well as a slight improvement in plasticity compared to the as-cast *** results of the tribological performance test indicated that the heat-treated composites exhibit lower average friction coefficient,specific wear rate,and worn surface roughness compared to the as-cast *** the heat treatment processes studied,the composite solution heated at 1,150 °C/1 h followed by air cooling,then 950 °C/1 h followed by air cooling,and finally 500 °C/4 h followed by air cooling,demonstrates the highest levels of hardness,compressive strength,and wear *** improvements are attributed to the combined effects of solid solution strengthening,grain refinement,and the pinning of dislocation slip.

关键词： titanium matrix composites heat treatment mechanical properties tribological properties

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Systematic adsorption process of petroleum hydrocarbon by immobilised petroleum-degradation bacteria system in degradation pathways

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Petroleum Science 2021年第5期18卷 1543-1550页

作者： Xin-Ge Fu Ke Shi jian-Liang Xue Chuan Chen Yu Bai Yan-Lu Qiao Yi-Xuan Liu Xiang-Ming hu Yu Gao Hao Yu College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdaoShandong266590China School of Environment Harbin Institute of TechnologyHaerbinHeilongjiang150001China Chinaunicom System Integration Co LtdNo.131Xidan North RoadBeijing100085China College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdaoShandong266590China

In order to effectively control petroleum hydrocarbon pollution by immobilisation technology,it is necessary to understanding the degradation pathways of petroleum hydrocarbon in immobilised petroleum-degradation bacteria ***,the adsorption in degradation process is rarely *** this study,adsorption process of petroleum hydrocarbon was synergistically studied by means of the surface properties,adsorption thermodynamics and molecular *** results indicate that the immobilised petroleum-degradation bacteria have many holes for the bacteria to *** diesel adsorption by immobilised petroleum-degradation bacteria is a spontaneous,entropy-increasing and endothermic *** is first adsorbed to the surface of immobilised petroleum-degradation bacteria through hydrogen bonding,and then is *** study provided substantial knowledge of immobilised technology in controlling petroleum hydrocarbon pollution.

关键词： Petroleum hydrocarbon pollution Immobilisation Adsorption-biodegradation Molecular simulation Bioremediation

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Antidepressant-like effects of albiflorin involved the NO signaling pathway in rats model of chronic restraint stress

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Chinese Journal of Natural Medicines 2020年第11期18卷 872-880页

作者： Zhu Ying-Li WANG Lin-Yuan ZHAO Dan-Ping WANG Cheng-Long ZHANG Rui FEI Wen-Ting WANG Jing-Xia ZHANG jian-jun School of Chinese Materia Medica Bejing University of Chinese MedicineBejing100029China School of Traditional Chinese Medicine Bejing University of Chinese MedicineBeijing100029China

The depressant-like effects of albiflorin(AF) were studied on stressed chronic restraint stress(CRS) rats. Experimental rats were subjected to immobilization stress for a daily 6 h-restraining in a plastic restrainer for continuous 21 d and were treated with 30 or 15 mg·kg-1 of AF for 21 d. Control rats were maintained in completely non stressed conditions. Behavioral tests and biochemical analysis were applied to investigating a regulatory mechanism of anti-stress of AF. Treatment with AF significantly restored the depressant-like behaviors. Besides, AF increased the levels of 5-hydroxytryptophan(5-HT), 5-hydroxyindoleacetic acid(5-HIAA),noradrenaline(NE) and dopamine(DA) in the hippocampus and increased the level of brain-derived neurotrophic factor(BDNF) in serum and protein expression in hippocampus. In addition, AF decreased the levels of hypothalamo-pituitary-adrenal(HPA) cascade,reduced the level of NO and c GMP in serum and inhibited the overexpression of 5-HT2AR m RNA and protein expression. Taken together, AF can modulate the NO-mediated network pathway in the hippocampus against stress-induced depressive-like *** physiological and behavioral changes allow rats to avoid potential deleterious effects of stress that may result from chronically elevated levels of glucocorticosteroids over days.

关键词： Paeonia lactiflora Albiflorin Chronic restraint stress Anti-stress NO-mediated pathway

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Perioperative advantages of modified laparoscopic vs open splenectomy and azygoportal disconnection

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World Journal of Gastroenterology 2014年第27期20卷 9146-9153页

作者： Guo-Qing jiang Ping Chen jian-jun Qian Jie Yao Xiao-Dong Wang Sheng-Jie Jin Dou-Sheng Bai Department of Hepatobiliary Surgery Clinical Medical College of Yangzhou University

AIM: To investigate perioperative outcomes in patients undergoing modified laparoscopic splenectomy or open splenectomy and azygoportal disconnection for portal hypertension.

关键词： Portal hypertension Laparoscopy Splenectomy Azygoportal disconnection Inflammatory response

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Positive Regulation of Phytochrome B on Chlorophyll Biosynthesis and Chloroplast Development in Rice

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Rice science 2013年第4期20卷 243-248页

作者： ZHAO Jie ZHOU Jin-jun WANG Ying-ying GU jian-wei XIE Xian-zhi Shandong Rice Research Institute College of Life Sciences Shandong Normal University

Phytochromes in rice are encoded by a gene family composed of three members, PHYA, PHYB, and PHYC. Through characterizing the phytochrome mutants and wild type （WT） in terms of photomorphogenesis, roles of individual phytochromes have been preliminarily explored in regulating rice de-etiolation, flowering time and fertility. However, little information has been reported about whether or how phytochromes affect chlorophyll biosynthesis and chloroplast development in rice. In this study, we compared the chlorophyll contents of wild type and the phyA, phyB and phyAphyB mutants grown under either white light （WL） or red light （R）. The results suggest that phyB perceives R to positively regulate chlorophyll biosynthesis, while the role of phyA can be detected only in the phyB-deficient mutant. Analyses of the expression levels of genes involved in chlorophyll biosynthesis revealed that phytochromes affected the chlorophyll biosynthesis by regulating protochlorophyll oxidoreductase A （PORA） expression. The role of phyB in chloroplast development was also analyzed, and the results suggest that phyB perceives R to regulate chloroplast development by affecting the numbers of chloroplasts and grana, as well as the chloroplast membrane system.

关键词： rice -phytochrome chlorophyll biosynthesis protochlorophyll oxidoreductase A chloroplastdevelopment

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A VUV photoionization mass spectrometric study on the OH-initiated photooxidation of isoprene with synchrotron radiation

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Journal of Environmental Sciences 2012年第12期24卷 2075-2082页

作者： Gang Pan Changjin hu Mingqiang huang Zhenya Wang Yue Cheng Zhi Liu Weixiong Zhao Weijun Zhang jun Chen Fuyi Liu Xiaobin Shan Liusi Sheng Key Laboratory of Atmospheric Composition and Optical Radiation Anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China Laboratory of Enviromental Spectroscopy nhui Irritate of Optics and Fine Mechanics Chinese Academy of Sciences Hefei 230031 China Department of Environental Science and Engineer'in Xiamen University Tan Kah Kee College ~Zt~angzhou 3'631~05 China National Synchrotron Radiation Laboratory School of Nuclear Science and Technology University of Science and Technology of China Hefei 230029 China

The gas-phase organic compounds resulting from OH-initiated photooxidation of isoprene have been investigated on-line by VUV photoiortization mass spectrometry based on synchrotron radiation for the first time. The photoionization efficiency curves of the corresponding gaseous products as well as the chosen standards have been deduced by gating the interested peaks in the photoionization mass spectra while scanning the photon energy simultaneously, which permits the identification of the pivotal gaseous products of the photooxidation of isoprene, such as formaldehyde （10.84 eV）, formic acid （11.38 eV）, acetone （9.68 eV）, glyoxal （9.84 eV）, acetic acid （10.75 eV）, methacrolein （9.91 eV）, and methyl vinyl ketone （9.66 eV）. Proposed reaction mechanisms leading to the formation of these key products were discussed, which were completely consistent with the previous works of different groups. The capability of synchrotron radiation photoionization mass spectrometry to directly identify the chemical composition of the gaseous products in a simulation chamber has been demonstrated, and its potential application in related studies of atmospheric oxidation of ambient volatile organic compounds is anticipated.

关键词： isoprene photooxidation smog chamber VUV photoionization mass spectrometry synchrotron radiation

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炭化气氛对黑液煤浆及不同煤种气化反应特性的影响

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燃烧科学与技术 2007年第2期13卷 101-106页

作者：匡建平周俊虎周志军刘建忠岑可法浙江大学能源清洁利用国家重点实验室杭州310027

煤气化前阶段的炭化气氛(温度、时间)影响到煤焦的气化反应特性.采用不同的炭化温度和炭化时间制备了黑液水煤浆、普通水煤浆以及其他5种煤的焦样,得到了各种煤焦气化反应的碳转化率;同时,通过扫描电子显微镜分析手段鉴别焦炭表面孔隙... 详细信息

煤气化前阶段的炭化气氛(温度、时间)影响到煤焦的气化反应特性.采用不同的炭化温度和炭化时间制备了黑液水煤浆、普通水煤浆以及其他5种煤的焦样,得到了各种煤焦气化反应的碳转化率;同时,通过扫描电子显微镜分析手段鉴别焦炭表面孔隙分布情况.试验结果表明,相同炭化气氛下得到的7种不同煤焦中,黄陵煤焦的气化活性最高,说明煤化程度越高反应性越低;由于黑液中有机物和无机物钠盐的影响,黑液水煤浆焦的气化特性高于普通水煤浆焦和新汶煤焦.煤焦的气化反应性,不仅与煤阶有关,还和煤焦中含氧官能团和无机化合物的含量有关,同时煤浆中外在添加的无机物组分也影响到煤焦的气化活性.

关键词：黑液水煤浆焦气化煤阶碳转化率

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Efficient ternary organic solar cells with high absorption coefficient DIB-SQ as the third component

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Chinese Physics B 2018年第5期27卷 558-563页

作者： hui-Xin Qi Bo-Han Yu Sai Liu Miao Zhang Xiao-Ling Ma jian Wang Fu-jun Zhang Key Laboratory of Luminescence and Optical Information of Mimstry of Education Beijing Jiaotong UniversityBeijing 100044China College of Physics and Electronic Engineering Taishan UniversityTaian 271021China

A series of organic solar cells(OSCs)are prepared with PTB7:PC71 BM as the host materials and DIB-SQ as the third *** power conversion efficienty(PCE)of OSCs can be improved from 6.79%to 7.92%by incorporating 6 wt%DIB-SQ into donors,resulting from the enhanced short circuit current density(J_(SC))and fill factor(FF).The increased JSCof the optimized ternary OSCs should be attributed to the enhanced photon harvesting of teranry active layer by incorporating ***,FF of the optimized ternary OSCs should be due to the optimied phase *** open circuit voltage(V_(OC))of tenray OSCs can be maintained at a constant of 0.75 V,indicating that all photogenerated holes willl be transported along the channels formed by PTB7.

关键词： organic solar cells power conversion efficiency the third component

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