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Ecological risk assessment of the Gannan Plateau,northeastern Tibetan Plateau

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Journal of Mountain Science 2018年第6期15卷 1254-1267页

作者： YUE Dong-xia zeng jian-jun YANG Chao ZOU Ming-liang LI Kai CHEN Guan-guang GUO jian-jun Xu Xiao-feng Meng Xing-min Key Laboratory of Western China＇s Environmental Systems （Ministry of Education） College of Earth and Environmental Sciences Lanzhou University Lanzhou 730000 China Key Laboratory of Desert and Desertification Northwest Institute of Eeo-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China School of Management Lanzhou University Lanzhou 730000 China

Desertification, soil salinization and grassland degradation are the major environmental hazards faced by the Gannan Plateau, northeastern Tibetan Plateau. Ecological risk assessment plays an important role in formulating environmental management strategies yet little attention to this region. In this study, we established an ecological risk assessment index system based on 30 evaluation indices in the categories of hydrometeorology, ecological environment, ground surface disturbance, and society and economy for the Gannan Plateau. An entropy method was used to calculate an index weight,and subsequently the matter-element method was used together with extension theory to establish a matter-element extension model of ecological risk. We assessed the ecological risk in this region by calculating the degree of association between index layer, system layer and target layer, and the cumulative ecological risk index. The degrees of ecological risk for the counties of the region were determined by using Arc GIS which would represent a spatial heterogeneity of the risk grade in production. Our results showed that the areas of high ecological risk were in Zhouqu County and Zhuoni County, and others were of low risk(Hezuo City, Diebu County, Xiahe County and Lintan County) or intermediate risk(Maqu County). The results of the assessment were in accord with the actual observed situation. Thus, our ecological risk assessment index system is appropriate for this region and suggests that high risk counties need a priori ecological protection. Such research could provide a technological support which would potentially prevent or reduce disasters by establishing an ecological barrier to promote the sustainable development of Gannan Plateau.

关键词： Matter-element Extension theory Ecological risk assessment Ecosystem GannanPlateau

Wide local excision could be considered as the initial treatment of primary anorectal malignant melanoma

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Chinese Medical Journal 2010年第5期123卷 585-588页

作者： ZHOU Hai-tao ZHOU Zhi-xiang ZHANG Hai-zeng BI jian-jun ZHAO Ping Department of Abdominal Surgery Cancer Hospital (Institute) Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100021 China

Background Anorectal malignant melanoma was a rare disease with extremely poor prognosis. The aim of this study was to explore the clinical characteristic, diagnosis and treatment strategies of anorectal malignant melanoma. Methods The data of 57 patients with anorectal malignant melanoma was collected and retrospectively analyzed. Results Rectal bleeding and anal mass were found to be common symptoms of anorectal malignant melanoma. The preoperative diagnosis rate of anorectal malignant melanoma was 48.6%. The overall 3-year and 5-year survival rate was 38.0% and 21.3% respectively. The 3-year survival rates of stage I and II patients were 63.0% and 16.7% respectively （P=0.000）, and the 5-year survival rates were 33.3% and 11.1% （P=0.001）, which both had significant statistic differences. The 3-year survival rate of patients undergone abdmoninoperineal resection and patients undergone wide local excision were 36.7% and 53.0% respectively （P=0.280）, while the 5-year survival rate were 24.1% and 23.1% （P=0.642）, which both had no significant statistic differences. Conclusions This study identified no survival advantage to abdominoperineal resection in treatment of anorectal malignant melanoma, and we propose that wide local excision could be considered as the initial treatment of choice.

关键词： anal rectal melanoma prognosis

工程教育专业认证下的课程建设实践探索——以“现代交流传动及其控制系统”为例

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教育教学论坛 2024年第6期 96-99页

作者：章勇高刘鹏叶满园曾建军华东交通大学电气与自动化工程学院江西南昌330013

课程建设是工程教育专业认证体系中的重要指标,通过“现代交流传动及其控制系统”课程建设,探索工程专业的课程建设模式。围绕专业培养目标和毕业要求,制定了课程教学大纲,确定了课程教学目标及与毕业要求的对应关系,讨论了课堂教学模... 详细信息

课程建设是工程教育专业认证体系中的重要指标,通过“现代交流传动及其控制系统”课程建设,探索工程专业的课程建设模式。围绕专业培养目标和毕业要求,制定了课程教学大纲,确定了课程教学目标及与毕业要求的对应关系,讨论了课堂教学模式和教学方式的组织形式,设计了课程考核方式及考核指标的标准,最后提出课程教学改进措施。从大纲制定、课堂教学组织、课程考核、考核评估及改进措施五个方面说明课程建设如何实现课程目标及与毕业要求的对应关系,满足工程教育专业认证要求,提升课程教学质量。

关键词：工程教育专业认证课程教学现代交流传动及其控制系统

Early gastric cancer recurrence after endoscopic submucosal dissection:Not to be ignored!

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World Journal of Gastrointestinal Oncology 2024年第1期16卷 8-12页

作者： Yan zeng jian Yang jun-Wen Zhang Department of Psychology The Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China Department of Gastroenterology Changdu People's Hospital of XizangChangdu 854000Tibet Autonomous RegionChina Department of Gastroenterology The First Affiliated Hospital of Chongqing Medical UniversityChongqing 400016China

This editorial comments on the article“Efficacy of multi-slice spiral computed tomography in evaluating gastric cancer recurrence after endoscopic submucosal dissection”.We focus on the importance of paying more attention to postendoscopic submucosal dissection(ESD)gastric cancer recurrence in patients with early gastric cancer(EGC)and how to manage it *** has been a wellknown treatment and the mainstay for EGC,with the advantages of less invasion and fewer complications when compared with traditional surgical *** a lower local recurrence rate after ESD,the problem of postoperative recurrence in patients with EGC has become increasingly non-ignorable with the global popularization of ESD technology and the increasing number of post-ESD patients.

关键词： Early gastric cancer Recurrence Endoscopic submucosal dissection Postoperative Prediction

地理科学专业“地理信息系统”课程的研究与实施

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教育教学论坛 2024年第28期 98-103页

作者：斯朗旺修曾建军范若冰王振禄兰州城市学院城市环境学院甘肃兰州730700 兰州城市学院教务处甘肃兰州730700 西安理工大学西北旱区及生态水利国家重点实验室陕西西安710048 甘肃农业大学资源环境学院甘肃兰州730070

地理科学专业“地理信息系统”课程是研究地理要素或者地理综合体空间分布规律、时间演变过程和区域特征的一门课程,是培育地理学专业人才队伍的关键课程,也是地理科学专业课程建设的重要组成部分。以兰州城市学院城市环境学院地理学专... 详细信息

地理科学专业“地理信息系统”课程是研究地理要素或者地理综合体空间分布规律、时间演变过程和区域特征的一门课程,是培育地理学专业人才队伍的关键课程,也是地理科学专业课程建设的重要组成部分。以兰州城市学院城市环境学院地理学专业为调查对象,深入分析了地理科学专业“地理信息系统”课程的教学现状,指出教学实施过程中存在的问题:一是教学大纲要求过高,二是教学内容与实际内容应用差距过大,三是教学方法单一,四是考核方式有待改革。根据上述问题,结合所学专业知识制定了行之有效的改善对策:一是明确“地理信息系统”课程教学大纲的教学改革方向,二是“地理信息系统”课程教学内容要符合实际应用需求,三是丰富“地理信息系统”课程教学方法,四是推动“地理信息系统”课程教学考核方式改革。以期有效推动“地理信息系统”课程教学的创新改革,为培育更多新时代地理科学专业人才队伍奠定基础。

关键词：地理信息系统(GIS) 教学技术地理科学专业

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen jian-jun He Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

Time-history performance optimization of flapping wing motion using a deep learning based prediction model

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Chinese Journal of Aeronautics 2024年第5期37卷 317-331页

作者： Tianqi WANG Liu LIU jun LI Lifang zeng School of Aeronautics and Astronautics Zhejiang UniversityHangzhou 310027China Huanjiang Laboratory Zhuji 311800China

Flapping Wing Micro Aerial Vehicles(FWMAVs)have caused great concern in various fields because of their high efficiency and *** wing motion is a very important factor that affects the performance of the aircraft,and previous works have always focused on the time-averaged performance ***,the time-history performance is equally important in the design of motion mechanism and flight control *** this paper,a time-history performance optimization framework based on deep learning and multi-island genetic algorithm is presented,which is designed in order to obtain the optimal two-dimensional flapping wing ***,the training dataset for deep learning neural network is constructed based on a validated computational fluid dynamics *** aerodynamic surrogate model for flapping wing is obtained after the convergence of *** surrogate model is tested and proved to be able to accurately and quickly predict the time-history curves of lift,thrust and ***,the optimization framework is used to optimize the flapping wing motion in two specific cases,in which the optimized propulsive efficiencies have been improved by over 40%compared with the ***,a dimensionless parameter C_(variation)is proposed to describe the variation of the time-history characteristics,and it is found that C_(variation)of lift varies significantly even under close time-averaged *** the importance of time-history performance in practical applications,the optimization that integrates the propulsion efficiency as well as C_(variation)is carried *** final optimal flapping wing motion balances good time-averaged and time-history performance.

关键词： FWMAV Flapping wing motion Deep learning Unsteady aerodynamic performance Optimization Time-history curve

Mass transfer in heap leaching of weathered crust elution deposited rare earth ore with Al_(2)(SO_(4))_(3) solution

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Journal of Rare Earths 2024年第6期42卷 1175-1181,I0007页

作者： Jingqun Yin Dedong zeng jun Tian Yaqing Weng Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang330096China School of Chemistry and Chemical Engineering Nanchang UniversityNanchang330031China

In order to increase efficiency and avoid NH^(4+)-N pollution in the leaching process of weathered crust elution-deposited rare earth ores,the mass transfer in heap leaching with Al_(2)(SO_(4))_(3) solution was simulated with column elution and experimentally *** results indicate that the leaching yield is also up to 99%for leaching with aluminum sulfate instead of ammonium *** optimal flow rate is 60 mL/h,the height equivalent to a theoretical plate(HETP)is 1.29 mm *** peak value position of RE^(3+)is 60 mL/h,Fe^(3+)is 100 mL/h,however,Al^(3+)is 150 mL/h,and the heap leaching process has kinetic separation effect.

关键词： Raree arths Mass transfer Process optimization Heapleaching Weathered crust elution-deposited rare earth ore

Strain-tuned electronic and valley-related properties in Janus monolayers of SWSiX2 (X = N, P, As)

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CHINESE PHYSICS B 2024年第9期33卷 487-492页

作者： Qi, Yunxi Zhao, jun zeng, Hui Nanjing Univ Posts & Telecommun New Energy Technol Engn Lab Jiangsu Prov Nanjing 210023 Peoples R China Nanjing Univ Posts & Telecommun Sch Sci Nanjing 210023 Peoples R China Nanjing Univ Sci & Technol Sch Microelect Nanjing 210094 Peoples R China

Exploring novel two-dimensional (2D) valleytronic materials has an essential impact on the design of spintronic and valleytronic devices. Our first principles calculation results reveal that the Janus SWSiX2 (X = N, P, As) monolayer has excellent dynamical and thermal stability. Owing to strong spin-orbit coupling (SOC), the SWSiX2 monolayer exhibits a valence band spin splitting of up to 0.49 eV, making it promising 2D semiconductor for valleytronic applications. The opposite Berry curvatures and optical selection rules lead to the coexistence of valley and spin Hall effects in the SWSiX2 monolayer. Moreover, the optical transition energies can be remarkably modulated by the in-plane strains. Large tensile (compressive) in-plane strains can achieve spin flipping in the SWSiN2 monolayer, and induce both SWSiP2 and SWSiAs(2 )monolayers transit from semiconductor to metal. Our research provides new 2D semiconductor candidates for designing high-performance valleytronic devices.

关键词： first-principles calculations two-dimensional valleytronic spintronic MOLECULAR-DYNAMICS MOS2 POLARIZATION LAYER