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Investigation of Formation Process of the Chrome-free Passivation Film of Electrodeposited Zinc

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Chinese Journal of Aeronautics 2007年第2期20卷 129-133页

作者： ZHU li-qun yang Fei HUANG Hui-jie School of Materials Science and Engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

The feasibility was investigated to substitute chrome-free passivation treatment of electrodeposited zinc in a titanium bath for chromate passivation treatment. The formation mechanism of the chrome-free passivation film was further analyzed. The surface mor- phologies and the elemental compositions of the treated samples with varied immersion times were observed by scanning electron mi- croscopy （SEM） and determined by energy dispersion spectrometry （EDS）, respectively. The electrode potential of the sample surface was recorded in the film formation process. The changes of the electrode potential are in accordance with that of SEM and EDS of the sample surface. The results of X-ray photoelectron spectroscopy （XPS） show the chrome-free passivation film composed ofZnO, SiO2, TiO2, Zn4Si207（OH）2, and SrF2. The anode zinc dissolution and the local pH value increase due to the cathode hydrogen ion reduction process result in the formation of the chrome-free passivation film. The macro-images of the chrome-free passivation films formed on electrodeposited zinc show that the color of the film changes from blue to iridescence with the increase of the immersion times.

关键词： electrodeposited zinc chrome-free pasivation film film formation process

Double hard X-ray peaks in RHESSI flares as evidence of chromospheric evaporation and implications for modifying the Neupert effect

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Research in Astronomy and Astrophysics 2009年第10期9卷 1155-1164页

作者： You-Ping li Wei-qun Gan yang Su Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

Among the RHESSI flare samples, we concentrated on a kind of flare that presents two successive peaks （that is, it presents both an impulsive phase and a gradual phase） in 12 - 25 keV light curves. Taking the C1.4 flare on 2002 August 12 as an example, we studied the light curves, spectra, and images in detail. Making full use of the capabilities of RHESSI, we showed some evidence to support the expected causal relationship between these two peaks; the first peak is mainly nonthermal, while the second peak is mainly thermal; the energy carried by nonthermal electrons during the first peak seems to be comparable to the thermal energy of the second peak. The morphologies of X-ray images and their evolutions provide additional evidence for this causality. We conclude that two such peaks in the 12 - 25 keV light curve are good evidence for the chromospheric evaporation. However, the maximum time of the second peak is later than the end time of the first peak, suggesting that for some events, a modification of the traditional Neupert effect could be necessary by inclusion of a time delay, which might be partly related to the filling of the loop by evaporated material.

关键词： Sun flares -- Sun X-rays, gamma-rays

Ensuring consistency of Web services transaction

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 59-66页

作者： WANG Xiao-jun li yang-qun WU Xiao-mei MIN li-juan Institute of Information and Network Technology Nanjing University of Posts and Telecommunications Nanjing 210003 China Foreign Languages Office Nanjing Institute of Politics Nanjing 210003 China

Composite Web services provide promising prospects for conducting cross-organizational Web service transactions. Such transactions generally require longer processing time and manipulate financially critical data. To efficiently manage these Web services transactions, isolation is commonly relaxed, but inconsistency will be caused by concurrently executing isolation-relaxing transactions. This article proposes an extension to the WS-Business Activity Protocol, which ensures the consistent executions of isolation-relaxing Web service transactions, and which is based on transaction dependency graphs distributed over multiple nodes. Furthermore, this article presents several algorithms implementing the protocol, and introduces the implement of a prototype system.

关键词： Web services transaction model transaction management protocol consistency

Ca^(2+) cytochemical changes of hepatotoxicity caused by halothane and sevoflurane in enzyme-induced hypoxic rats

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World Journal of Gastroenterology 2005年第32期11卷 5025-5028页

作者： Wei-Feng Yu li-qun yang Mai-Tao Zhou Zhi-Qiang liu Quan li Department of Anesthesiology Eastern Hepatobiliary Surgery Hospital the Second Military Medical University Shanghai 200438 China

AIM： To investigat the relation between hepatotoxicity of halothane and sevoflurane and altered hepatic calcium homeostasis in enzyme-induced hypoxic rats. METHODS： Forty-eight rats were pretreated with phenobarbital and randomly divided into six groups （eight in each group） and exposed to O2/N2/1.2 MAC anesthetics for 1 h： normal control （NC）, 21% O2/79% N2; hypoxic control （HC）, 14% O2/86% N2; normal sevoflurane （NS）, 21% O2/ N2/1.2MAC sevoflurane; hypoxic sevoflurane （HS）, 14% O2/N2/1.2MAC sevoflurane; normal halothane （NH）21%O2/79%N2/1.2MAC halothane; hypoxic halothane （HH）, 14%O2/N2/1.2MAC halothane. liver specimens and blood were taken 24 h after exposure to calcium and determined by EDX microanalysis. RESULTS： The liver of all rats given halothane （14% O2） had extensive centrilobular necrosis and denaturation. Morphologic damage was accompanied with an increase in serum glutarnic pyruvic transminase. In groups NH and HH, more calcium was precipitated in cytoplasm and mitochondria. CONCLUSION： These results suggest that halothane increases cytosolic Ca^2＋ concentration in hepatocytes. Elevation in Ca^2＋ concentration is implicated in the mechanism of halothane-induced hepatotoxicity. sevoflurane is less effective in affecting hepatic calcium homeostasis than halothane.

关键词： Ca^2+ cytochemistry Hepatotoxicity Calcium homeostasis Halothane Sevoflurane

Na^+ and Water Uptake in Relation to the Radial Reflection Coefficient of Root in Arrowleaf Saltbush Under Salt Stress

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Journal of Integrative Plant Biology 2007年第9期49卷 1334-1340页

作者： Xin-Fu Bai Jian-Jun Zhu Ping Zhang Yan-Hua Wang li-qun yang Lei Zhang College of life Sciences Ludong University Yantai 264025 China

The response of halophyte arrowleaf saltbush （Atriplex triangularis Willd） plants to a gradient of salt stress were investigated with hydroponically cultured seedlings. Under salt stress, both the Na^＋ uptake into root xylem and negative pressures in xylem vessels increased with the elevation of salinity （up to 500 mol/m^3） in the root environment. However, the increment in negative pressures in root xylem far from matches the decrease in the osmotic potential of the root bathing solutions, even when the osmotic potential of xylem sap is taken into consideration. The total water potential of xylem sap in arrowleaf saltbush roots was close to the osmotic potential of root bathing solutions when the salt stress was low, but a progressively increased gap between the water potential of xylem sap and the osmotic potential of root bathing solutions was observed when the salinity in the root environment was enhanced. The maximum gap was 1.4 MPa at a salinity level of 500 mol/m^3 without apparent dehydration of the tested plants. This discrepancy could not be explained with the current theories in plant physiology. The radial reflection coefficient of root in arrowleaf saltbush decreased with the enhanced salt stress was and accompanied by an increase in the Na^＋ uptake into xylem sap. However, the relative Na^＋ in xylem exudates based on the corresponding NaCl concentration in the root bathing solutions showed a tendency of decrease. The results showed that the reduction in the radial reflection coefficient of roots in the arrowleaf saltbush did not lead to a mass influx of NaCl into xylem when the radial reflection coefficient of the root was considerably small; and that arrowleaf saltbush could use small xylem pressures to counterbalance the salt stresses, either with the uptake of large amounts of salt, or with the development of xylem pressures dangerously negative. This strategy could be one of the mechanisms behind the high resistance of arrowleaf saltbush plants to

关键词： anti-osmosis arrowleaf saltbush (Atriplex triangularis Willd) radial reflection coefficient of root salt stress xylem pressure

Controlled low central venous pressure reduces blood loss and transfusion requirements in hepatectomy

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World Journal of Gastroenterology 2014年第1期20卷 303-309页

作者： Zhi li Yu-Ming Sun Fei-Xiang Wu li-qun yang Zhi-Jie Lu Wei-Feng Yu Department of Anesthesiology Eastern Hepatobiliary Surgery Hospitalthe Second Military Medical University

AIM: To evaluate the effect of low central venous pressure (LCVP) on blood loss and blood transfusion in patients undergoing hepatectomy.

关键词： Low central venous pressure Hepatectomy Blood loss Blood transfusion

Prediction of the thermal conductivity of Mg–Al–La alloys by CALPHAD method

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 129-137页

作者： Hongxia li Wenjun Xu Yufei Zhang Shenglan yang lijun Zhang Bin liu qun Luo Qian li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al *** accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high thermal ***,databases for predicting temperature-and composition-dependent thermal conductivities must be *** this study,Mg-Al-La alloys with different contents of Al2La,Al3La,and Al11La3phases and solid solubility of Al in the α-Mg phase were *** influence of the second phase(s) and Al solid solubility on thermal conductivity was *** results revealed a second phase transformation from Al_(2)La to Al_(3)La and further to Al_(11)La_(3)with the increasing Al content at a constant La *** degree of the negative effect of the second phase(s) on thermal diffusivity followed the sequence of Al2La>Al3La>Al_(11)La_(3).Compared with the second phase,an increase in the solid solubility of Al in α-Mg remarkably reduced the thermal *** the basis of the experimental data,a database of the reciprocal thermal diffusivity of the Mg-Al-La system was established by calculation of the phase diagram (CALPHAD)*** a standard error of±1.2 W/(m·K),the predicted results were in good agreement with the experimental *** established database can be used to design Mg-Al alloys with high thermal conductivity and provide valuable guidance for expanding their application prospects.

关键词： magnesium alloy thermal conductivity thermodynamic calculations materials computation

Impact of Sky Conditions on Net Ecosystem Productivity over a “Floating Blanket” Wetland in Southwest China

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Advances in Atmospheric Sciences 2024年第2期41卷 355-368页

作者： Yamei SHAO Huizhi liU qun DU yang liU Jihua SUN Yaohui li Jinlian li State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100029China Yunnan Meteorological Observatory Kunming 530100China College of Aviation Meteorology Civil Aviation Flight University of ChinaGuanghan 618307China Meteorological Bureau of Tengchong County Baoshan 679100China

Based on eddy covariance(EC) measurements during 2016–20, the effects of sky conditions on the net ecosystem productivity(NEP) over a subtropical “floating blanket ” wetland were investigated. Sky conditions were divided into overcast, cloudy, and sunny conditions. On the half-hourly timescale, the daytime NEP responded more rapidly to the changes in the total photosynthetic active radiation(PARt) under overcast and cloudy skies than that under sunny skies. The increase in the apparent quantum yield under overcast and cloudy conditions was the greatest in spring and the least in summer. Additionally, lower atmospheric vapor pressure deficit(VPD) and moderate air temperature were more conducive to enhancing the apparent quantum yield under cloudy skies. On the daily timescale, NEP and the gross primary production(GPP) were higher under cloudy or sunny conditions than those under overcast conditions across seasons. The daily NEP and GPP during the wet season peaked under cloudy skies. The daily ecosystem light use efficiency(LUE) and water use efficiency(WUE) during the wet season also changed with sky conditions and reached their maximum under overcast and cloudy skies, respectively. The diffuse photosynthetic active radiation(PAR_d) and air temperature were primarily responsible for the variation of daily NEP from half-hourly to monthly timescales, and the direct photosynthetic active radiation(PAR_b) had a secondary effect on NEP. Under sunny conditions, PAR_b and air temperature were the dominant factors controlling daily NEP. While daily NEP was mainly controlled by PAR_d under cloudy and overcast conditions.

关键词： diffuse radiation eddy covariance NEP controlling factors wetland path analysis

Effect of remote ischemic preconditioning among donors and recipients following pediatric liver transplantation:A randomized clinical trial

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World Journal of Gastroenterology 2021年第4期27卷 345-357页

作者： Bo Qi Xiao-Qiang Wang Shu-Ting Pan Pei-Ying li ling-Ke Chen Qiang Xia li-qun yang Wei-Feng Yu Department of Anesthesiology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Clinical Center for Investigation Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200127China Department of Transplantation and Hepatic Surgery Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200120China

BACKGROUND Studies suggested that remote ischemic preconditioning(RIPC)may effectively lessen the harmful effects of ischemia reperfusion injury during organ transplantation *** To investigate the protective effects of RIPC on living liver donors and recipients following pediatric liver *** From January 2016 to January 2019 at Renji Hospital Affiliated with Shanghai Jiao Tong University School of Medicine,208 donors were recruited and randomly assigned to four groups:S-RIPC group(no intervention;n=55),D-RIPC group(donors received RIPC;n=51),R-RIPC group(recipients received RIPC,n=51)and DR-RIPC group(both donors and recipients received RIPC;n=51).We primarily evaluated postoperative liver function among donors and recipients and incidences of early allograft dysfunction,primary nonfunction and postoperative complications among *** RIPC did not significantly improve alanine transaminase and aspartate aminotransferase levels among donors and recipients or decrease the incidences of early allograft dysfunction,primary nonfunction,and postoperative complications among *** protective effects were observed,including a lower creatinine level in the D-RIPC group than in the S-RIPC group on postoperative day 0(Plimited for recipients who received living liver transplantation,and no significant improvement of the prognosis was observed in recipients.

关键词： Pediatric liver transplantation Remote ischemic preconditioning Postoperative complications Ischemia reperfusion injury Primary nonfunction Hepatology