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3-D RIGID PLASTIC FEM SIMULATION OF EXTRUDING-BULGING PROCESS OF TEE TUBES

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中国有色金属学会会刊：英文版 1999年第2期9卷 45-50页

作者： wang, Chenlu shan, Debin Lu, Yan Harbin Inst of Technology Harbin China

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关键词： FEMextrudingbulging processtee tubes

Effects on the mixing process of a coiled tube after a T-junction:Simulation and correlation

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2441-2447页

作者： shan Zhu Kai wang Yangcheng Lü State Key Laboratory of Chemical Engineering Department of Chemical Engineering Tsinghua University

Simulations were performed to examine the effects of a coiled tube after a T-junction on the mixing and flow characteristics. A coiled tube was found to have two effects: inducing a radial flow and flattening the axial velocity distribution, which enhances and weakens the mixing, respectively. In the straight tube section connecting the Tjunction and coiled tube, the latter may dominate and cause the mixing to deteriorate. An experiment was performed with the Villermaux/Dushman method to verify the simulation results. Based on a mixing performance simulation with various fluid and geometric structure parameters, a dimensionless correlation was obtained that can be used to determine the mixing intensity along the coiled tube with a deviation of less than 1.5%.These results provide guidance for designing a coiled tube or optimizing the operating conditions to meet the mixing requirements of specific chemical processes.

关键词： Mixing T-junction Simulation Coiled tube Correlation Flow

Improving performance by creating a native join-index for OLAP

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Frontiers of Computer Science 2011年第2期5卷 236-249页

作者： Yansong ZHANG shan wang Jiaheng LU National Survey Research Center at Renmin University of China Beijing 100872 China Key Laboratory of the Ministry of Education for Data Engineering and Knowledge Engineering Renmin University of China Beijing 100872 China School of Information Renmin University of China Beijing 100872 China

The performance of online analytical processing （OLAP） is critical for meeting the increasing requirements of massive volume analytical applications. Typical techniques, such as in-memory processing, column-storage, and join indexes focus on high perfor- mance storage media, efficient storage models, and reduced query processing. While they effectively perform OLAP applications, there is a vital limitation： main- memory database based OLAP （MMOLAP） cannot provide high performance for a large size data set. In this paper, we propose a novel memory dimension table model, in which the primary keys of the dimension table can be directly mapped to dimensional tuple addresses. To achieve higher performance of dimensional tuple access, we optimize our storage model for dimension tables based on OLAP query workload features. We present directly dimensional tuple accessing （DDTA） based join （DDTA- JOIN）, a technique to optimize query processing on the memory dimension table by direct dimensional tuple access. We also contribute by proposing an optimization of the predicate tree to shorten predicate operation length by pruning useless predicate processing. Our experimental results show that the DDTA-JOIN algorithm is superior to both simulated row-store main memory query processing and the open-source column-store main memory database MonetDB, thanks to the reduced join cost and simple yet efficient query processing.

关键词： directly dimensional tuple accessing (DDTA) – DDTA JOIN – native join index – predicate tree

Structural investigation of the zirconium-titanium based amino trimethylene phosphonate hybrid coating on aluminum alloy

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Acta Metallurgica Sinica(English Letters) 2009年第3期22卷 161-166页

作者： Shuanghong wang Changsheng LIU Fengjun shan Key Laboratory for Anisotropy and Texture of Materials Ministry of Education Northeastern University Shenyang 110004 China Material ＆ Chemical Engineering College Liaoning University of Technology Jinzhou 121001 China

A zirconium-titanium based amino trimethylene phosphonate hybrid coating on AA6061 aluminum alloys was formed by dipping in a fluorotitanate/zirconate acid and amino trimethylene phosphonic acid （ATMP） solution for improving the lacquer adhesion and corrosion resistance as a substitute of chromate coatings. The morphology and structure of the hybrid coating were studied by means of scanning electron microscopy （SEM） and atomic force microscopy （AFM）. The surface composition and structure characteristics were also investigated by means of X-ray photoelectron spectroscopy （XPS） and Fourier transformation infra-red spectroscopy （FTIR）. The results of SEM and AFM show that the hybrid coating present piece particle distribution which is much denser than that of the zirconium-titanium coating. The results of XPS and FTIR indicate that the hybrid coating is a hybrid composite structure composed of both the zirconium-titanium and amino trimethylene phosphonate coatings.

关键词： Fluorotitanate/fluorozirconate Amino trimethylene phosphonic acid Hybrid coating Aluminum alloys Corrosion resistance

Organic semiconductor heterojunctions: electrode-independent charge injectors for high-performance organic light-emitting diodes

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Light(Science & Applications) 2016年第1期5卷 570-576页

作者： Yong-Hua Chen Dong-Ge Ma heng-Da Sun Jiang-shan Chen Qing-Xun Guo Qiang wang Yong-Biao Zhao State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Macromolecular Science and Engineering School of EngineeringCase Western Reserve UniversityClevelandOH 44106USA School of Materials Science and Engineering Shaanxi Normal UniversityXi’an 710062China Luminous Center of Excellence for Semiconductor Lighting and DisplaysSchool of Electrical and Electronic EngineeringNanyang Technological UniversitySingapore 639798Singapore

Organic light-emitting diodes(OLEDs)are driven by injected charges from an anode and a *** low and high work function metals are necessary for the effective injection of electrons and holes,***,we introduce a fully novel design concept using organic semiconductor heterojunctions(OSHJs)as the charge injectors for achieving highly efficient OLEDs,regardless of the work functions of the *** contrast to traditional injected charges from the electrodes,the injected charges originate from the *** device performance was shown to be significantly improved in efficiency and stability compared to conventional ***,the OLEDs based on OSHJs as charge injectors still exhibited an impressive performance when the low work function Al was replaced by air-and chemistry-stable high work function metals,such as Au,Ag,and Cu,as the cathode contact,which has been suggested to be difficult in conventional *** concept challenges the conventional design approach for the injection of charges and allows for the realization of practical applications of OLEDs with respect to high efficiency,selectable electrodes,and a long lifetime.

关键词： charge injection OLEDs organic semiconductor heterojunctions

Natural astaxanthin enhanced antioxidant capacity and improved semen quality through the MAPK/Nrf2 pathway in aging layer breeder roosters

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Journal of Animal Science and Biotechnology 2022年第2期13卷 578-592页

作者： shan Gao Nuo heng Fang Liu Yong Guo Yu Chen Liang wang Hemin Ni Xihui Sheng Xiangguo wang Kai Xing Longfei Xiao Xiaolong Qi Animal Science and Technology College Beijing University of AgricultureBeijing 102206China School of Economics and Management Beijing University of AgricultureBeijing 102206China Department of Livestock and Poultry Products Testing Beijing General Station of Animal HusbandryBeijing 100107China

Background:Natural astaxanthin(ASTA)has strong antioxidant properties and has been widely used as a health product to improve human ***,the effects of ASTA on the reproductive performance of aging roosters have been poorly *** aimed to investigate the effects of dietary ASTA on semen quality and antioxidant capacity in aging roosters and to explore the potential mechanism of semen quality change via antioxidation defense ***:In the present study,9653-week-old Jinghong No.1 layer breeder roosters were fed a corn-soybean meal basal diet containing 0,25,50,or 100 mg/kg ASTA for 6 ***:Semen quality in the ASTA groups remarkably improved than that in the control group,and antioxidant activities,the abilities to scavenge hydroxyl radicals and superoxide anions,increased gradually with ASTA addition(P<0.05).In addition,the mRNA levels of antioxidant enzymes as well as the mRNA and protein levels of the mitogen-activated protein kinase(MAPK)and nuclear factor-erythroid 2-related factor 2(Nrf2)were markedly increased in the 50-100 mg/kg ASTA group(P<0.05).Conclusions:Collectively,these results demonstrate that dietary ASTA may improve semen quality by increasing antioxidant enzyme activities and the ability to scavenge hydroxyl radicals,which may be related to upregulation of the MAPK/Nrf2 pathway.

关键词： Aging rooster Antioxidant capacity MAPK/Nrf2 pathway Natural astaxanthin Semen quality

From basic to clinical:Anatomy of Denonvilliers’fascia and its application in laparoscopic radical resection of rectal cancer

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World Journal of Gastrointestinal Surgery 2023年第10期15卷 2108-2114页

作者： Zhou Chen Xiao-Jing Zhang Hao-Dong Chang Xiao-Qian Chen shan-shan Liu Wei wang Zhi-heng Chen Yu-Bin Ma Liang wang Department of Gastrointestinal Oncology Surgery TheAffiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina Department of General Surgery The Affiliated Hospital of Qinghai UniversityXining 810000Qinghai ProvinceChina

The total mesorectal excision(TME)approach has been established as the gold standard for the surgical treatment of middle and lower rectal *** approach is widely accepted to minimize the risk of local recurrence and increase the long-term survival rate of patients undergoing ***,standardized TME causes urogenital dysfunction in more than half of patients,thus lowering the quality of life of *** note,pelvic autonomic nerve damage during TME is the most pivotal cause of postoperative urogenital *** anatomy of the Denonvilliers’fascia(DVF)and its application in surgery have been investigated both nationally and ***,controversy exists regarding the basic to clinical anatomy of DVF and its application in ***,it is a hotspot of concern and research to improve the postoperative quality of life of patients with rectal cancer through the protection of their urinary and reproductive functions after radical ***,this study systematically describes the anatomy of DVF and its appli-cation in surgery,thus providing a reference for the selection of surgical treatment modalities and the enhancement of postoperative quality of life in patients with middle and low rectal cancer.

关键词： Denonvilliers’fascia Total mesorectal excision Middle and low rectal cancer Laparoscopic surgery Dissect

基于RFM分析的公共图书馆科技信息服务社会价值探究——以吉林省图书馆为例

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四川图书馆学报 2025年第1期 36-44页

作者：张勇郭山王桂敏吉林省图书馆长春130021

以经济学的思维方式认识与分析公共图书馆科技信息服务社会价值,有利于公共图书馆找准自身发展定位,为未来的长足发展提供依据。文章通过对公共图书馆及用户开展调研,并采用RFM分析方法,对服务的社会价值与现实困境进行探究。结果显示,... 详细信息

以经济学的思维方式认识与分析公共图书馆科技信息服务社会价值,有利于公共图书馆找准自身发展定位,为未来的长足发展提供依据。文章通过对公共图书馆及用户开展调研,并采用RFM分析方法,对服务的社会价值与现实困境进行探究。结果显示,科技信息服务的社会价值度与用户的推荐意愿、使用频率、消费意愿三大因素相关,在主观意愿选择上与满意度、服务了解程度、服务多样性等因素存在着相关性。针对影响因素,探讨提升公共图书馆科技信息服务社会价值的实现路径,以便促进服务工作的有效开展。

关键词：公共图书馆科技创新科技信息服务社会价值 RFM分析

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近62年我国极端高温事件的时空变化特征

高原气象 2025年第1期44卷 201-213页

作者：卢珊胡泽勇沈姣姣王百朋王能辉赵乾甲陕西省气象服务中心陕西西安710014 中国科学院西北生态环境资源研究院寒旱区陆面过程与气候变化重点实验室甘肃兰州730000 陕西省突发事件预警信息发布中心陕西西安710015 陕西秦盾防雷技术有限公司陕西西安710014

利用1961-2022年全国664个地面观测站的逐日最高气温资料,系统分析了全国和各分区极端高温事件及其起讫日期的时空分布及演变特征。结果表明,我国有近9成极端高温事件集中在夏季,其中出现在7月的极端高温事件占全年总数的39.3%。全国极... 详细信息

利用1961-2022年全国664个地面观测站的逐日最高气温资料,系统分析了全国和各分区极端高温事件及其起讫日期的时空分布及演变特征。结果表明,我国有近9成极端高温事件集中在夏季,其中出现在7月的极端高温事件占全年总数的39.3%。全国极端高温事件在近62年迅速增加,极端高温日数和高温极值在9成以上的站点监测到增加趋势。极端高温事件在高海拔地区的增加更为明显,青藏地区的极端高温日数每10年增加2.9天,高温极值增幅为0.34℃·(10a)^(-1)。极端高温事件开始日期和结束日期在全国大部分站点分别呈现出明显的提前和推迟趋势,受起讫日期的反向变化影响,极端高温事件持续期的增加趋势更为突出。西南地区是各分区中极端高温事件持续期增加最快的地区,其增加速度达10.8 d·(10a)^(-1)。长时间维持的连续性极端高温过程对人民生产生活造成严重威胁,进入21世纪以来,连续性极端高温过程在我国呈现出高发态势。华南和西南地区的连续性极端高温过程的增加较为明显,其中华南地区的连续性极端高温过程频次和累积日数每10年分别增加0.5次和2.5天,均为各分区中最高。

关键词：极端高温事件连续性极端高温过程起讫日期时空演变