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Variations of methane stable isotopic values from an Alpine peatland on the eastern Qinghai-Tibetan Plateau

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Acta Geochimica 2021年第5期40卷 473-483页

作者： qian guo Haijun Peng Bing Hong Hu Yao Yongxuan Zhu Hanwei Ding Ning An Yetang Hong State Key Laboratory of Environmental Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Bayinbuluk Alpine Wetland Carbon Flux Research Station Chinese Flux Observation and Research NetworkBeijingChina CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

Isotopic signature is a powerful tool to discriminate methane(CH_(4)) source types and constrain regional and global scale CH_(4) *** on the Qinghai-Tibetan Plateau are poorly understood about the isotopic signature of CH_(4) due to the limited experimental *** this study,three campaigns of diurnal air samples spacing 2-3 h were taken from an alpine peatland on the eastern Qinghai-Tibetan Plateau to investigate its source signal *** CH_(4) concentration and its stable carbon isotope(δ^(13)C-CH_(4)) were measured to derive the carbon isotopic signature of the CH_(4) source using the Keeling plot *** variation patterns in CH_(4) concentration and δ^(13)C-CH_(4) were observed during summertime,with depleted δ^(13)C-CH_(4) signals and high CH_(4) concentration appearing at *** δ^(13)C-CH4 signature during summer was calculated to be-71 % ± 1.3%,which falls within the range of other wetland studies and close to high-latitude *** boundary layer dynamic and CH_(4) source were supposed to influence the measured CH_(4) concentration and δ^(13)C-CH_(4.)Further investigations of CH_(4) isotopic signals into the nongrowing season are still needed to constrain the δ^(13)C-CH_(4) signature and its environmental controls in this region.

关键词： Stable carbon isotope Methane Alpine peatland Qinghai-Tibetan plateau Diurnal variation

Optical multi-color monitoring of OJ 287 from 2006 to 2012

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Research in Astronomy and Astrophysics 2017年第8期17卷 57-68页

作者： qian guo Ding-Rong Xiong Jin-Ming Bai Xu-Liang Fan Wei-Min Yi Yunnan Observatories Chinese Academy of Sciences Kunming 650216 China Key Laboratory for the Structure and Evolution of Celestial Objects Chinese Academy of Sciences Kunming 650216 China Center for Astronomical Mega-Science Chinese Academy of Sciences Beijing 100012 China University of Chinese Academy of Sciences Beijing 100049 China

We present our optical multi-color monitoring of the BL Lac object OJ 287 from January 2006to December 2012 in the V,R and I bands.A relatively active state in OJ 287 has been found over all monitored epochs,among which the variations of average magnitude in V/R/I bands were measured with ?V=1.956 mag,?R=2.067 mag and ?I=2.115 mag,*** reliable intraday variability is detected,but possible variability is detected on 16 *** relative variation amplitudes fall into the range between 1% and 8%,with the majority between 2% and 4%.No time lags have been detected,but strong correlations exist among light curves in the three *** bluer-when-brighter trend is dominant over intraday timescales,which supports the shock-in-jet *** combining with additional V/R band data obtained from SMARTS and the Steward Observatory,we also find a bluer-when-brighter trend over a long-term *** possible periods of 513,176,36,30,26,17 and 14 d are found in all time-series data sets from 2006 to *** explanations about these periods are given.

关键词： BL Lacertae objects individual(OJ 287)—galaxies active—galaxies photometry

Simplified Calculation of Flow Resistance of Suspension Bridge Main Cable Dehumidification System

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Fluid Dynamics & Materials Processing 2021年第6期17卷 1195-1211页

作者： Zhiyuan Tu Fusheng Peng Zijie Wei guo qian Jie Wang Chunjie Huang College of National Defense Engineering Army Engineering University of PLANanjing210007China 92318 Troops Beijing100089China

To calculate the flow resistance of a main cable dehumidification system,this study considers the air flow in the main cable as the flow in a porous medium,and adopts the Hagen–Poiseuille equation by using average hydraulic radius and capillary bundle models.A mathematical derivation is combined with an experimental study to obtain a semi-empirical flow resistance ***,Fluent software is used to simulate the flow resistance across the main cable relative to the experimental *** on the actual measured results for a Yangtze River bridge,this study verifies the semi-empirical formula,and indicates that it can be applied in actual engineering.

关键词： Main cable dehumidification computational fluid dynamics dry air semi-empirical flow resistance formula

Determination of the controlled landing trajectory of Chang’E-1 satellite and the coordinate analysis of the landing point on the Moon

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Chinese Science Bulletin 2010年第13期55卷 1240-1245页

作者： LI JinLing guo Li qian ZhiHan JIANG DongRong ZHENG WeiMin HONG XiaoYu Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

Based on the tracking observations of radio ranges and VLBI delays of Chang’E-1 (CE-1) satellite during the controlled landing on the Moon on March 1, 2009, the landing trajectory and the coordinates of the landing point are determined by positioning analysis. It is shown that the landing epoch (the emission epoch of the last signal) of CE-1 satellite on the Moon was at UTC8h13m6.51s. The lunar longitude, latitude and surface height of the landing point in the lunar primary axes frame are respectively 52.2732°, 1.6440° and –3.56 km (the reference lunar radius is 1738 km). The uncertainties are 0.0040°, 0.0168° and 0.18 km. The corresponding uncertainty in the tangential direction of the lunar surface is 0.52 km and the three-dimensional (3D) positioning uncertainty is 0.55 km. It is accordingly deduced that even with the present technical specifications of the radio ranges and VLBI delays, the 1 km 3D positioning precision could be guaranteed for the lander in the second stage of China’s Lunar Explora- tion Project. Concerning the trace determination of the rover on the lunar surface, because only telemetry signal will be emitted, VLBI would be the sole tracking technique from the Earth. The application of the constraint of geocentric distance is shown to be helpful to improving the positioning precision. It is worthy to pay close attention to the applications of the same beam VLBI technique, the lunar topographic model and the on-board observations of the lander and rover to the position/trace determination of the rover.

关键词：卫星轨道控制嫦娥一号着陆点月球测定

Compared effects of “solid-based” hydrogen peroxide pretreatment on disintegration and properties of waste activated sludge

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Chinese Chemical Letters 2022年第3期33卷 1293-1297页

作者： Hai-Chao Luo Wan-qian guo Qi Zhao Hua-Zhe Wang Nan-Qi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China

The effects of two solid-based hydrogen peroxides sodium percarbonate(SPC) and calcium peroxide(CP)on waste activated sludge(WAS) disintegration were investigated. Both oxidants achieved efficient WAS disintegration for the synergistic effect of alkaline and oxidation. The strong alkaline condition led to the leakage of ammonia and the existence of abundant calcium ions accelerated the fixation of phosphorus via precipitation in CP WAS disintegration process. However, the spongy-like layer and low p H condition retarded the release of gaseous ammonia in SPC group. Hydroxyl radical was the main oxygen reactive species in SPC approaches which were more intense than CP by electron spin resonance(ESR) *** treated WAS contented more small particle size matter and total suspended solids(TSS) increased dramatically. In conclusion, CP pretreated sludge was more suitable for fertilization, while SPC was in favor of anaerobic digestion. This study clarified the differences between these two oxidants and their intermediates on nutrients release in sludge disintegration.

关键词： Waste activated sludge “Solid-based”hydrogen peroxide Oxygen reactive species Sludge disintegration Nutrients release

Inadvertent perioperative hypothermia and surgical site infections after liver resection

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Hepatobiliary & Pancreatic Diseases International 2024年第6期23卷 579-585页

作者： Yi-De Zhou Wen-Yuan Zhang guo-Hao Xie Hui Ye Li-Hua Chu Yu-qian guo Yi Lou Xiang-Ming Fang Department of Anesthesiology and Intensive Care Medicine the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Background:In the overall surgical population,inadvertent perioperative hypothermia has been associated with an increased incidence of surgical site infection(SSI).However,recent clinical trials did not validate this *** study aimed to investigate the potential correlation between inadvertent perioperative hypothermia and SSIs following liver ***:This retrospective cohort study included all consecutive patients who underwent liver resection between January 2019 and December 2021 at the First Affiliated Hospital,Zhejiang University School of *** temperature managements were implemented for all patients included in the *** propensity score matching(PSM)was performed to reduce the baseline imbalances between the normothermia and hypothermia *** and after PSM,univariate analyses were performed to evaluate the correlation between hypothermia and *** regression analysis was performed to determine whether hypothermia was an independent risk factor for postoperative transfusion and major *** analyses were performed for diabetes mellitus,age>65 years,and major liver ***:Among 4000 patients,2206 had hypothermia(55.2%),of which 150 developed SSI(6.8%).PSM yielded 1434 individuals in each *** PSM,the hypothermia and normothermia groups demonstrated similar incidence rates of SSI(7.0%vs.6.3%,P=0.453),postoperative transfusion(13.7%vs.13.3%,P=0.743),and major complications(10.1%vs.9.0%,P=0.309).Univariate regression analysis revealed no significant effects of hypothermia on the incidence of SSI in the group with the highest hypothermia exposure[odds ratio(OR)=1.25,95%confidence interval(CI):0.84-1.87,P=0.266],the group with moderate exposure(OR=1.00,95%CI:0.65-1.53,P=0.999),or the group with the lowest exposure(OR=1.11,95%CI:0.73-1.65,P=0.628).The subgroup analysis revealed similar *** liver function,patients in the hypothermia group demonstrated l

关键词： Surgical site infection Perioperative hypothermia Liver resection Postoperative complications Intraoperative care

Body mass index and outcomes of patients with cardiogenic shock:A systematic review and meta-analysis

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World Journal of Clinical Cases 2022年第30期10卷 10956-10966页

作者： Wen-Xia Tao guo-Ying qian Hong-Dan Li Feng Su Zhou Wang Department of Cardiovascular Medicine Huzhou Cent HospitalAffiliated Cent Hospital Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina

BACKGROUND Cardiogenic shock continues to be a highly morbid complication that affects around 7%-10% of patients with acute myocardial infarction or heart ***,obesity has become a worldwide *** To analyze the impact of higher body mass index(BMI) on outcomes of patients with cardiogenic *** A systematic and comprehensive search was undertaken on the electronic databases of PubMed,Embase,ScienceDirect,CENTRAL,and Google Scholar for all types of studies comparing mortality outcomes of patients with cardiogenic shock based on *** studies defined overweight or obese patients based on the World Health Organization BMI *** data were then extracted and assessed on the basis of the Reference Citation Analysis(https://***/).RESULTS Five studies were *** pooled analysis of multivariable-adjusted ratios,we noted a statistically significantly reduced risk of mortality in overweight/obese vs normal patients(three studies;odds ratio [OR] = 0.92,95% confidence interval [CI]:0.85-0.98,I~2 = 85%).On meta-analysis,we noted that crude mortality rates did not significantly differ between overweight/obese and normal patients after cardiogenic shock(OR = 0.95,95%CI:0.79-1.15,I~2 = 99%).The results were not stable on sensitivity analysis and were associated with substantial *** Current evidence on the association between overweight/obesity and mortality after cardiogenic shock is scarce and *** obesity paradox might exist in patients with cardiogenic shock but could be confounded by the use of mechanical circulatory *** is a need for further studies to clarify this relationship.

关键词： Obese Overweight Myocardial infarction Shock Mortality

Feasibility and simulation model of a pilot scale membrane bioreactor for wastewater treatment and reuse from Chinese traditional medicine

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Journal of Environmental Sciences 2007年第2期19卷 129-134页

作者： REN Nan-qi YAN Xian-feng CHEN Zhao-bo HU Dong-xue GONG Man-li guo Wan-qian School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China School of Power and Nuclear Engineering Harbin Engineering University Harbin 150001 China

The lack and pollution of water resource make wastewater reuse necessary. The pilot scale long-term tests for submerged membrane bioreactor were conducted to treat the effluents of anaerobic or aerobic treatment process for the high-strength Chinese traditional medicine wastewater. This article was focused on the feasibility of the wastewater treatment and reuse at shorter hydraulic retention time （HRT） of 5.0, 3.2 and 2.13 h. MLSS growth, membrane flux, vacuum values and chemical cleaning periods were also investigated. The experimental results of treating two-phase anaerobic treatment effluent demonstrated that the CODfilt was less than 100 mg/L when the influent COD was between 500-10000 mg/L at HRT of 5.0 h, which could satisfy the normal discharged standard in China. The experimental results to treat cross flow aerobic reactor effluent demonstrated that the average value of CODfilt was 17.28 mg/L when the average value of influent COD was 192.84 mg/L at HRT of 2.13 h during 106 d, which could completely meet the normal standard for water reuse. The maximum MLSS and MLVSS reached 24000 and 14500 mg/L at HRT of 3.2 h respectively. Membrane flux had maximal resume degrees of 94.7% at vacuum value of 0.02 MPa after cleaning. Chemical cleaning periods of membrane module were 150 d. A simulation model of operational parameters was also established based on the theory of back propagation neural network and linear regression of traditional mathematical model. The simulation model showed that the optimum operational parameters were suggested as follows： HRT was 5.0 h, SRT was 100 d, the range of COD loading rate was between 10.664-20.451 kg/（m3.d）, the range of MLSS was between 7543-13694 mg/L.

关键词： submerged membrane bioreactor (SMBR) Chinese traditional medicine wastewater hydraulic retention time (HRT) simulation model pilot scale test

Effect of Axial Magnetic Field on the Microstructure, Hardness and Wear Resistance of TiN Films Deposited by Arc Ion Plating

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Acta Metallurgica Sinica(English Letters) 2015年第8期28卷 984-993页

作者： Yan-Hui Zhao Wen-Jin Yang Chao-qian guo Yu-Qiu Chen Bao-Hai Yu Jin-Quan Xiao Institute of Metal Research Chinese Academy of Sciences School of Chemistry and Material Science University of Science and Technology of China

TiN films were deposited on stainless steel substrates by arc ion plating. The influence of an axial magnetic field was examined with regard to the microstructure, chemical elemental composition, mechanical properties and wear resistance of the films. The results showed that the magnetic field puts much effect on the preferred orientation, chemical composition, hardness and wear resistance of TiN films. The preferred orientation of the TiN films changed from（111） to（220） and finally to the coexistence of（111） and（220） texture with the increase in the applied magnetic field intensity. The concentration of N atoms in the TiN films increases with the magnetic field intensity, and the concentration of Ti atoms shows an opposite trend. At first, the hardness and elastic modulus of the TiN films increase and reach a maximum value at 5 m T and then decrease with the further increase in the magnetic field intensity. The high hardness was related to the N/Ti atomic ratio and to a well-pronounced preferred orientation of the（111） planes in the crystallites of the film parallel to the substrate surface. The wear resistance of the Ti N films was significantly improved with the application of the magnetic field, and the lowest wear rate was obtained at magnetic field intensity of 5 m T. Moreover, the wear resistance of the films was related to the hardness H and the H3/E＊2 ratio in the manner that a higher H3/E＊2 ratio was conducive to the enhancement of the wear resistance.

关键词： Magnetic field Arc ion plating TiN films Hardness Wear resistance