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Petroleum Research 2024年第1期9卷 61-71页

作者： Aymen A.Lazim Maher J.Ismail Maher M.Mahdi Geoscience Department Zubair Field Operation DivisionBasra Oil CompanyIraq Basrah Oil Company WQ1 FODBasrahIraq University of Basrah College of ScienceGeology Dept.BasrahIraq

The Mishrif Formation(Cenomanian-E Turonian)is one of the most important geological formations in the Middle East and Iraq because it contains enormous petroleum *** is considered to be the first reservoir in the region,and is still being studied because of its economic *** carbonate of the Mishrif Formation derives from a variety of depositional settings,including mid-ramp,shoal,lagoon,and *** five main microfacies discussed in this paper are wackestone,packstone,grainstone,floatstone,and *** most frequent fossilised components found in the Mishrif Formation are rudists,benthic foraminifera,echinoderms,burrows molluscs,and *** to the microfacies and analysed wireline log data,the sequence stratigraphy of the studied formation is composed of two regression *** parasequences of transgressive-regressive cycles make up the depositional sequence of the Mishrif *** standard depositional environments seem to demonstrate a gradual regression,beginning with a short period of the outer ramp,then a steady period of the mid-ramp,and ending in the intertidal ***,the study recorded two regional maximum flooding surfaces:K-135 and *** former is present in the lowermost part of the formation,while the other lies in the *** study shows a close relationship between facies(environments)and hydrocarbon *** increased accumulation focuses on the lower part of the studied formation,and seems to be lower in the upper part of the formation as a result of changes in the environment of deposition.

关键词： Mishrif formation Cenomanian Sequence stratigraphy Zubair oilfield Iraq

Optimization of magnetic field design for Hall thrusters based on a genetic algorithm

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Plasma Science and Technology 2024年第7期26卷 82-92页

作者：谭睿杭观荣王平阳 School of Mechanical Engineering Shanghai Jiaotong UniversityShanghai 200240People’s Republic of China division of Electric Propulsion Shanghai Institute of Space PropulsionShanghai 201112People’s Republic of China

Magnetic field design is essential for the operation of Hall *** study focuses on utilizing a genetic algorithm to optimize the magnetic field configuration of SPT70.A 2D hybrid PIC-DSMC and channel-wall erosion model are employed to analyze the plume divergence angle and wall erosion rate,while a Farady probe measurement and laser profilometry system are set up to verify the simulation *** results demonstrate that the genetic algorithm contributes to reducing the divergence angle of the thruster plumes and alleviating the impact of high-energy particles on the discharge channel wall,reducing the erosion by 5.5%and 2.7%,*** analysis indicates that the change from a divergent magnetic field to a convergent magnetic field,combined with the upstream shift of the ionization region,contributes to the improving the operation of the Hall thruster.

关键词： magnetic field design genetic algorithm divergence angle erosion of discharge channel convergent magnetic field

Study on Temperature Disaster Indicators of Passion Fruit in Southwest Fujian, China

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Journal of Geoscience and Environment Protection 2024年第1期12卷 1-12页

作者： Shiyun Mou Ping Shao Yuchen Shi Shujie Yuan Lixin Su Plateau Atmosphere and Environment Key Laboratory of Sichuan Province School of Atmospheric Sciences Chengdu University of Information Technology Chengdu China Airport operation Management Committee of Korla Licheng Airport Korla China Jilin Institute of Meteorogical Sciences Changchun China Jilin Provincial Key Laboratory of Changbai Mountain Meteorology & Climate Change Changchun China

In China, meteorological forecasting relies on meteorological data obtained from regional and national stations. However, there were discrepancies between the data collected from the meteorological station at the passion fruit growing base and the data from regional and national stations. Consequently, the high and low temperature disaster indicators determined by the meteorological station at the passion fruit growing base cannot be applied to meteorological forecasting. To address this issue and facilitate the monitoring and early warning of high and low temperature disasters in passion fruit cultivation in Fujian, China, we used multi-source hourly temperature data (including the data from meteorological observation stations in passion fruit growing bases, the nearest regional stations, and national surface conventional meteorological observation stations) in three cities in southwestern Fujian (Longyan, Sanming, and Zhangzhou) spanning the years 2020 to 2022. By employing comprehensive statistical analysis methods (0.5 interval division and Cumulative frequency), we identified that passion fruit in southwestern Fujian was susceptible to high temperature disasters during the blooming-fruiting period, as well as low temperature disasters during the sprouting period. Consequently, we developed high and low temperature disaster indicators based on data from regional and national stations for different phenological periods of passion fruit in this region.

关键词： Passion Fruit High Temperature Disaster Indicator Low Temperature Disaster Indicator Disaster Frequency Disaster Degree

Running Temperature and Mechanical Stability of Grease as Maintenance Parameters of Railway Bearings

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International Journal of Automation and computing 2010年第2期7卷 160-166页

作者： Jan Lundberg Aditya Parida Peter Sderholm division of operation and Maintenance Engineering Lule University of Technology

Spherical roller bearings in railway car wheels are critical components whose failure may have catastrophic consequences. The present study aims to analyse the mechanical stability of greases and temperature of bearings as indicators for condition-based bearing maintenance. The performed case study includes nine fully-formulated commercial greases examined in the wheel bearings of five ore cars operated in northern Scandinavia. The studied ore cars travelled a distance of about 300 000 km during a period of three years. Small samples of the greases were taken on eight occasions to test their mechanical stability. In addition, the temperatures of the bearings were continuously recorded. After the test period, the wear, electrical damage, and corrosion of the bearings were examined. One of the findings is that the shear stress of the grease at a certain shear velocity （the certain yieldstress （CEY） value） is a good maintenance indicator and is highly dependent on the grease type. The bearing＇s wear, electrical damage and corrosion also depend on the grease type. However, no oxidation of the greases was identified. The paper also outlines a systematic methodology to determine an overall maintenance indicator for railway roller bearings which is based on the field measurements.

关键词： Maintenance mechanical stability railway roller bearings grease lubrication.

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高压输电线路雷击闪络的实验室研究(英文)

高电压技术 2011年第11期37卷 2707-2714页

作者： Thongchai Disyadej Stanislaw Grzybowski northern region operation division Electricity Generating Authority of ThailandPhitsanulok 65000Thailand Department of Electrical and Computer Engineering Mississippi State UniversityMississippi StateMS 39762USA

This paper presents an investigation on the attractive width of high voltage transmission lines to lightning *** order to design the optimal lightning protection,the estimated number of lightning flashes on the line, which is based on its attractive width,needs to be *** investigation was performed using experiments with model tests at the Mississippi State University High Voltage *** laboratory experiments,a total of 2,100 negative and positive switching impulse voltages were applied to transmission line models from a conducting rod,which represented a lightning downward *** tested models of transmission lines on a scale of 1:100 were *** effects of overhead ground wires,phase conductors,tower structures,and the magnitude and polarity of lightning strokes were also *** attractive width increased gradually with the height of overhead ground wires and towers as well as the magnitude of the lightning stroke *** polarity had an impact on the attractive width,and the attractive width for negative polarity was larger than that for positive *** taller tower had more effect on flash distribution to transmission lines than the shorter *** experimental results agree with the actual transmission line observations published in *** new expressions for the attractive width of transmission lines,based on the experimental results,were *** accurate estimation of the attractive width can help electric power utilities plan transmission systems reliably and *** detailed description of the background problem,proposed method,experimental results,and analysis are presented in this paper.

关键词： lightning high voltage transmission line laboratory experiment test model

Comparison between surgical outcomes of colorectal cancer in younger and elderly patients

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World Journal of Gastroenterology 2011年第12期17卷 1642-1648页

作者： Longxue Jin Norio Inoue Naoki Sato Susumu Matsumoto Hitoshi Kanno Yuko Hashimoto Kazuhiro Tasaki Kinya Sato Shun Sato Katsutoshi Kaneko Center for Digestive Diseases Northern Fukushima Medical Center Fukushima 960-0502 Japan Department of Pathology Fukushima Medical University Hospital Fukushima 960-1295 Japan division of Anesthesiology Northern Fukushima Medical Center Fukushima 960-0502 Japan

AIM:To compare the outcome of surgical treatment of colorectal adenocarcinoma in elderly and younger ***:The outcomes of 122 patients with colorectal adenocarcinoma who underwent surgical treatment between January 2004 and June 2009 were *** clinicopathological and blood biochemistry data of the younger group(operation time,intraoperative blood loss,hospital stay,time to resumption of oral intake,or *** elderly group had a significantly higher rate of hypertension and cardiovascular *** perioperative serum total protein and albumin levels were significantly lower in the elderly than in the younger *** serum carcinoembryonic antigen level was lower in the elderly than in the younger group,and there was a significant decreasing trend after the operation in the elderly ***:The short-term outcomes of surgical treatment in elderly patients with colorectal adenocarcinoma were *** treatment in elderly patients was considered a selectively effective approach.

关键词： Colorectal 肿瘤老病人病态 Carcinoembryonic 抗原 C 反应的蛋白质

Method for generating non-circular gear with addendum modification and its application in transplanting mechanism

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International Journal of Agricultural and Biological Engineering 2020年第6期13卷 68-75页

作者： Maile Zhou Yuchao Yang Mingxu Wei Daqing Yin School of Agricultural Engineering Jiangsu UniversityZhenjiang 212013China College of Engineering Northeast Agricultural UniversityHarbin 150030China Key Laboratory of Modern Agricultural Equipment Technology in northern Cold region Harbin 150030China

With a focus on the design of tooth profiles of non-circular gears with addendum modifications that conform to the given complex transmission ratio curves and based on a series of discrete point sets on the pitch curves,the criteria for tooth profile distortion and undercut in non-circular gears were *** the constraint of no tooth profile distortion and undercut,the addendum modification coefficient was introduced into the calculation of the distorted and undercut segments of the tooth profile of a non-circular gear,and the addendum modification coefficient of each contact point of the non-circular gear was *** on the generating principle for gear shaping with gear cutters,a theoretical model for calculating the tooth profile of non-circular gears with addendum modification was *** cutting and radial feeding motions of the pinion cutter were ignored,and only the meshing motion was *** involute tooth profiles of the pinion cutter enveloped the tooth profile of the non-circular gear.3D automatic non-circular gear model generation software was developed,which was a secondary development product of the software UG.A non-circular gear in a rice potted seedling transplanting mechanism was designed,and the transplanter was developed and *** test results showed that the designed tooth profile of non-circular gear achieved the variable transmission ratios required by the transplanting *** the transplanting efficiencies were 140 plants/min,160 plants/min and 180 plants/min,the transplanter completed the rice potted seedling transplanting operation with high quality.

关键词： non-circular gear tooth profile generation addendum modification coefficient enveloping characteristics transplanting mechanism

Simulation evaluation and future prediction of the IPCC—AR4 GCMs on the extreme temperatures in China

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Acta Oceanologica Sinica 2008年第3期27卷 112-123页

作者： WANG Ji JIANG Zhihong SONG Jie LOU Dejun Beijing region Climate Center Beijing 100089 China Jiangsu Province Key Laboratory of Meteorological Disaster Nanjing University of Information Science ＆ Technology Nanjiang 210044 China Department of Geography Northern Illinois University DeKalb Illinois 60115 USA Qiqihar Meteorological Bureau Qiqihar 161006 China

On the basis of the temperature observations during 1961-2000 in China, seven coupled general circulation models＇（GCMs） extreme temperature products are evaluated supplied by the Intergovernmental Panel on Climate Change＇ s 4th Assessment Report （IPCC-AR4）. The extreme temperature indices in use are frost days （FD）, growing season length （GSL）, extreme temperature range （ETR）, warm nights （TN90）, and heat wave duration index （HWDI）. Results indicate that all the seven models are capable of simulating spatial and temporal variations in temperature characteristics, and their ensemble acts more reliable than any single one. Among the seven models, GFDL-CM2.0 and MIROC3.2 performances are much better. Besides, most of the models are able to present linear trends of the same positive/negative signs as the observations but for weaker intensities. The simulation effects are different on a nationwide basis, with 110°N as the division, east （west） of which the effects are better （worse） and the poorer over the Qinghai-Tibetan Plateau in China. The predictions for the 21st century on emissions scenarios show that except decreases in the FD and ETR, other indices display significant increasing trend, especially for the indices of HWDI and TN90, which represent the notable extreme climate. This indicates that the temperature-related climate is moving towards the extreme. In the late 21st century, the GSL and TN90 （HWDI） increase most notably in southwest China （the Qinghai-Tibetan Plateau）, and the FD decrease most remarkably in the Qinghai-Tibetan Plateau, northwest and northeast of China. Apart from South China, the yearly change range of the extreme temperature is reduced in most of China.

关键词： IPCC-AR4 GCMs extreme climate assessment extreme temperature index

Optimization model and algorithm for system operation division of labor at two-way marshaling station

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Science China(Technological Sciences) 1998年第5期41卷 511-518页

作者：牛惠民胡安洲 Department of Transportation Management Engineering Northern Jiaotong University Beijing China

Based on the systematic analysis of the operation process at two-way marshaling station, the operation ways of through car flows, sorting car flows and loading car flows are comprehensively studied. An optimal model of system operation division of labor based on resource constraint is constructed. The model is solved by using genetic algorithm, and the improving strategy for solving the model is proposed. The application example indicates that the model and algorithm can effectively solve the problem of operation division of labor at two-way marshaling station.

关键词： two-way marshaling station operation division of labor car flows joining operation process model genetic algorithm.

Characteristics of PM_(2.5) and Its Reactive Oxygen Species in Heating Energy Transition and Estimation of Its Impact on the Environment and Health in China——A Case Study in the Fenwei Plain

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Advances in Atmospheric Sciences 2023年第7期40卷 1175-1186页

作者： Zexuan WANG Hongmei XU Rong FENG Yunxuan GU Jian SUN Suixin LIU Ningning ZHANG Dan LI Tao WANG Linli QU Steven Sai Hang HO Zhenxing SHEN Junji CAO Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Loess and Quaternary Geology(SKLLQG) Key Lab of Aerosol Chemistry&PhysicsInstitute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Agricultural Technology&Extension Central of Xi'an City Xi’an 710061China Hong Kong Premium Services and Research Laboratory KowloonHong Kong Special Administrative Region(SAR)China division of Atmospheric Sciences Desert Research InstituteRenoNV 89512United States

To reduce the adverse effects of traditional domestic solid fuel,the central government began implementing a clean heating policy in northern China in *** coal is an alternative low-cost fuel for rural households at the present *** this study,18 households that used lump coal,biomass,and clean coal as the main fuel were selected to evaluate the benefits of clean heating transformation in Tongchuan,an energy city in the Fenwei Plain,*** indoor and personal exposure(PE)samples of fine particulate matter(PM_(2.5))were synchronically *** with the lump coal and biomass groups,the indoor PM_(2.5)concentration in the clean coal group is 43.6%and 20.0%lower,respectively,while the values are 16.8%and 21.3%lower,respectively,in the personal exposure ***_(2.5)-bound elements Cd,Ni,Zn,and Mn strongly correlated with reactive oxygen species(ROS)levels in all fuel groups,indicating that transition metals are the principal components to generate oxidative *** a reliable estimation method,it is predicted that after the substitution of clean coal as a household fuel,the all-cause,cardiovascular,and respiratory disease that causes female deaths per year could be reduced by 16,6,and 3,respectively,in the lump coal group,and 22,8,and 3,respectively,in the biomass *** though the promotion of clean coal has led to impressive environmental and health benefits,the efficiencies are still *** environmental-friendly energy sources must be promoted in the rural regions of China.

关键词： clean energy transition solid fuel combustion PM_(2.5) ROS Fenwei Plain