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Influence of Blade Thickness on Transient Flow Characteristics of Centrifugal Slurry Pump with Semi-open Impeller

Chinese Journal of Mechanical Engineering 2016年第6期29卷 1209-1217页

作者： tao Yi YUAN Shouqi LIU Jianrui ZHANG Fan tao jianping National Research Center of Pumps and Pumping System Engineering and Technology Jiangsu University Zhenjiang 212013 China Yixing taoye Nonmetallic Chemical Machinery Factory Co. Ltd. Wuxi 214222 China

As the critical component, the impellers of the slurry pumps usually have blades of a large thickness. The increasing excretion coefficient of the blades affects the flow in the impeller resulting in a relatively higher hydraulic loss, which is rarely reported. In order to investigate the influence of blade thickness on the transient flow characteristics of a centrifugal slurry pump with a semi-open impeller, transient numerical simulations were carried out on six impellers, of which the meridional blade thickness from the leading edge to trailing edge varied from 5-10 mm, 5-15 mm, 5-20 mm, 10-10 mm, 10-15 mm, and 10-20 mm, respectively. Then, two of the six impellers, namely cases 4 and 6, were manufactured and experimentally tested for hydraulic performance to verify the simulation results. Results of these tests agreed reasonably well with those of the numerical simulation. The results demonstrate that when blade thickness increases, pressure fluctuations at the outlet of the impeller become severe. Moreover, the standard deviation of the relative velocity in the middle portion of the suction sides of the blades decreases and that at the outlet of the impeller increases. Thus, the amplitude of the impeller head pulsation for each case increases. Meanwhile, the distribution of the time-averaged relative flow angle becomes less uniform and decreases at the outlet of the impeller. Hence, as the impeUer blade thickness increases, the pump head drops rapidly and the maximum efficiency point is offset to a lower flow rate condition. As the thickness of blade trailing edge increases by 10 mm, the head of the pump drops by approximately 5 m, which is approximately 10 % of the original pump head. Futhermore, it is for the first time that the time-averaged relative flow angle is being considered for the analysis of transient flow in centrifugal pump. The presented work could be a useful guideline in engineering practice when designing a centrifugal slurry pump with thick i

关键词： centrifugal slurry pump blade thickness transient flow characteristics time-averaged relative flow angle semi-openimpeller

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Driving forest succession in karst areas of Chongqing municipality over the past decade

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Forest Ecosystems 2020年第1期7卷 26-36页

作者： Qiang Xiao Yang Xiao Yuan Liu jianping tao Key Laboratory of Eco-environments in Three Gorges Reservoir Region(Ministry of Education) Chongqing Key Laboratory of Plant Ecology and Resources Research in Three Gorges Reservoir RegionSchool of Life SciencesSouthwest UniversityChongqing 400715China Chongqing University of Arts and Sciences Chongqing 402160China College of Biology and Environmental Sciences Jishou UniversityJishou 416000China

Background:Karst areas in southwestern China exhibit ecological degradation in the form of rocky *** governments launched large-scale afforestation and other ecological restoration programs to curb this *** thickness is a key limiting factor for vegetation restoration in Karst areas,but the relationship between ecological restoration and soil thickness remains ***,afforestation consumes large amounts of water,which impacts water supply in karst *** this study,we used GIS and statistical analyses to determine rocky desertification sensitivity and its driving factors in karst areas of Chongqing municipality over the past ***:Soil thickness is one of the key factors that restrict ecological restoration of rocky *** 2000 to 2010,rocky desertification sensitivity in karst areas was on the rise along with an increase in *** of high sensitivity were mainly distributed in Pengshui County,Wulong District,and Youyang County;Shizhu County had the lowest overall incidence of *** distribution of rocky desertification was significantly affected by rainfall and soil *** analysis showed that the main factors controlling changes in rocky desertification in natural forest over time were precipitation which explained 23.73%of total variance,and soil thickness which explained 23.42%of total *** thickness and soil water content had a higher correlation coefficient(at 0.516)in natural forests than in planted ***:This study showed that increases in soil thickness in a karst area had a significant positive impact on the fragile ecological *** indicates that ecosystem restoration in karst areas will benefit from addressing soil thickness.

关键词： Rocky desertification GIS Karst areas Ecological restoration Ecological drivers

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Response of clonal plasticity of Fargesia nitida to different canopy conditions of subalpine coniferous forest

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Frontiers in Biology 2008年第4期3卷 463-469页

作者： jianping tao Lixia SONG Yongjian WANG Weiyin ZHANG Key Laboratory of Eco-environments in Three Gorges Reservoir Region(Ministry of Education) School of Life ScienceSouthwest UniversityChongqing 400715China Institute of Forest Ecology Environment and ProtectionChinese Academy of ForestryBeijing 100091China

The aim of this study is to explore the effects of canopy conditions on clump and culm numbers,and the morphological plasticity and biomass distribution patterns of the dwarf bamboo species Fargesia ***,we investigated the effects of canopy conditions on the growth and morphological characteristics of ***,and the adaptive responses of *** to different canopy conditions and its ecological *** results indicate that forest canopy had a significant effect on the genet density and culm number per clump,while it did not affect the ramet *** tended to be few and large in gaps and forest edge plots,and small under forest understory *** ramets showed an even distribution under the closed canopy,and cluster distribution under gaps and forest edge *** forest canopy had a significant effect on both the ramets’biomass and biomass *** light conditions promoted ramet growth and biomass *** amounts of biomass in gaps and forest edge plots were shown by the higher number of culms per clump and the diameter of these *** closed canopy,the bamboos increased their branching angle,leaf biomass allocation,specific leaf area and leaf area ratio to exploit more favourable light conditions in these *** spacer length,specific spacer length and spacer branching angles all showed significant differences between gaps and closed canopy *** larger specific spacer length and spacer branching angle were beneficial for bamboo growth,scattering the ramets and exploiting more favourable light *** summary,this study shows that to varying degrees,*** exhibits both a wide ecological amplitude and high degree of morphological plasticity in response to differing forest canopy ***,the changes in plasticity enable the plants to optimize their light usage efficiency to promote growth and increase access to resources available in heterogeneous light environments.

关键词： Fargesia nitida clonal plant plasticity subalpine coniferous forest Wolong Nature Reserve

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Research Progress and Prospect of County-wide Finance in China between 1991 and 2013 Based on Bibliometric Method

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Asian Agricultural Research 2016年第1期8卷 1-6,12页

作者： Qi HUANG jianping tao College of Economics & Management Huazhong Agricultural University Hubei Rural Development Research Center

In order to visually and comprehensively grasp scientific research progress of the county-wide finance in China,and explore new breakthrough point of county-wide finance studies,this paper took China National Knowledge Infrastructure( CNKI) database as research platform and made a bibliometrical study of literature indexed in CNKI between 1991 and 2013 by advanced search method. Results indicate that relevant researches take on the trend of firstly increasing then decreasing and finally steady; research hot spots mainly focus on county-wide finance and county-wide economy,county-wide inclusive finance,and county-wide finance exclusion. Based on literature review,it found subject research of county-wide finance and county-wide economic issue has become a relatively mature issue. The extension research of countywide finance exclusion and inclusive finance is devoted to remove finance exclusion. This research is a blind spot in this field and may become a breakthrough point of stimulating re-growth of county-wide finance researches.

关键词： County-wide finance Research progress Prospect Bibliometrical analysis

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Detection of Praziquantel Content in Praziquantel Injection by HPLC

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Animal Husbandry and Feed Science 2014年第6期6卷 342-344页

作者： Xiao Wenhua Yang Haifeng Jin Liqin Li Yongjun Bu Shijin tao jianping Jiangsu Agri-animal Husbandry Vocational College Jiangsu Beikang Pharmaceutical Co. Ltd

[ Objective] To detect the praziquantel content in praziquantel injection by HPLC. [ Methods ] Chromatographic conditions were as follows： chromato- graphic colmnn was Diamonsil Cls column （ 150 mm x 4.6 mm, 5 μm） ; column temperature was 25 ℃ ; mobile phase was acetonitrile-water （60：40） ; flow rate was 1.0 mL/min ; UV detection wavelength was 210 nm; and injection volume was 20 μL. [ Results ] Praziquantel showed good linear relationship within the con- centration of 6.037 - 90.55 g/L （ r = 0. 999 4） ; the average recovery rate was 99.24%, and RSD was 0. 769%. [Condusions ] This method was simple, rap- id, sensitive and repeatable, and could be used for the quality control of praziquantel injection.

关键词： Praziquantel HPLC Detection

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渣浆泵叶轮磨损的数值模拟及试验

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农业工程学报 2014年第21期30卷 63-69,F0004页

作者：陶艺袁寿其张金凤张帆陶建平江苏大学流体机械工程技术研究中心镇江212013 国家水泵及系统工程技术研究中心镇江212013 江苏省宜兴市陶冶非金属化工机械有限公司无锡214222

为研究渣浆泵运行过程中叶轮的磨损情况,该文以一台离心式工程塑料渣浆泵为研究对象,对其全流场进行了结构化网格划分,首先对包括设计工况点在内的5个工况进行了清水条件下的数值模拟,并与试验数据进行对比,发现最大误差不超过5%,设计... 详细信息

为研究渣浆泵运行过程中叶轮的磨损情况,该文以一台离心式工程塑料渣浆泵为研究对象,对其全流场进行了结构化网格划分,首先对包括设计工况点在内的5个工况进行了清水条件下的数值模拟,并与试验数据进行对比,发现最大误差不超过5%,设计工况点误差不超过3%,说明所用数值模拟方法得到的结果是可信的。随后基于ANSYS CFX商用软件中的Particle欧拉多相流模型,对模型泵内流场进行了固液两相数值模拟并进行了快速磨损试验,模拟与试验结果表明:叶轮磨损较严重的部位位于叶片进口边、流道中前段靠近叶片压力面的后盖板内侧、叶片压力面与后盖板交界处及叶片压力面端面;背叶片的磨损主要发生在叶片压力面外缘,并由此处开始往轮毂处发展,磨损形状大致呈抛物线型,分析认为隔舌处的高压引起流道中颗粒相回流撞击背叶片外缘是造成背叶片磨损的主要原因。通过模拟结果与试验结果的对比,证明所采用的数值模拟方法可以有效地预测渣浆泵运行时叶轮的磨损,其结果可较好地解释磨损产生的原因,该研究可为今后渣浆泵叶轮抗磨损性能的优化设计提供参考。

关键词：泵数值方法叶轮渣浆泵试验研究固液两相流磨损

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三四级市场连锁超市的促销策略

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中国市场 2008年第2期 84-86页

作者：陶剑平丽水职业技术学院

连锁超市的迅速发展给人们的生活带来很多方便,而在三四级市场中连锁超市的经营状态和经营业绩却不尽理想,超市彼此之间的竞争也日益激烈,为扩大销售额,吸引更多的消费者购物,连锁超市采用适当的促销策略尤其重要。本文针对连锁超市在... 详细信息

连锁超市的迅速发展给人们的生活带来很多方便,而在三四级市场中连锁超市的经营状态和经营业绩却不尽理想,超市彼此之间的竞争也日益激烈,为扩大销售额,吸引更多的消费者购物,连锁超市采用适当的促销策略尤其重要。本文针对连锁超市在经营中,从促销理念、促销产品、促销技巧等方面所存在的问题进行分析思考,提出了相应的对策,为连锁超市在促销经营中达到预期目的而提供参考。

关键词：三四级市场连锁超市促销策略

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浅析广西与东盟文化产业的交流与合作

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东南亚纵横 2009年第12期 75-78页

作者：陶剑平浙江丽水职业技术学院财贸管理分院

中国与东盟都重视文化产业的发展,积极开展双方文化产业交流合作。广西在参与中国—东盟自由贸易区建设中具有得天独厚的优势,这在一定程度上推动广西走上国际文化交流的前沿。本文主要分析广西文化产业的发展现状、存在问题及广西在中... 详细信息

中国与东盟都重视文化产业的发展,积极开展双方文化产业交流合作。广西在参与中国—东盟自由贸易区建设中具有得天独厚的优势,这在一定程度上推动广西走上国际文化交流的前沿。本文主要分析广西文化产业的发展现状、存在问题及广西在中国—东盟背景下的文化产业交流与合作的优势及前景。

关键词：广西-东盟文化产业交流与合作

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政策性农业保险对农业生产水平影响效应的实证研究——基于全国31个省份面板数据分位数回归

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中国农业大学学报 2017年第12期22卷 163-173页

作者：代宁陶建平华中农业大学经济管理学院武汉430070 湖北农村发展研究中心武汉430070

基于2007—2015年全国31个省份的面板数据,利用面板分位数回归方法从农业保险发展水平与农业保险赔付水平2个维度实证分析了政策性农业保险对我国农业生产的影响,并针对实证结果进行了子样本的稳健性检验。分析结果表明:农业保险发展水... 详细信息

基于2007—2015年全国31个省份的面板数据,利用面板分位数回归方法从农业保险发展水平与农业保险赔付水平2个维度实证分析了政策性农业保险对我国农业生产的影响,并针对实证结果进行了子样本的稳健性检验。分析结果表明:农业保险发展水平可以显著促进农业生产水平的提高,但在不同分位下其影响效应存在差别,在较低分位上,农业保险发展水平对农业生产水平促进作用较大,随着分位点的提高,农业保险发展水平对农业生产水平的促进作用逐渐降低。然而农业保险赔付水平对农业生产水平的促进作用相对较小。因此完善政策性农业保险制度应当努力扩大农业保险覆盖面,重点扩大农业生产水平较低地区的农业保险覆盖面,着力提高农业保险保障和赔付水平,增加农业保险险种。

关键词：农业保险面板分位数回归农业生产影响效应

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扶贫效率、形态分布与精准优化:秦巴山片区例证

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改革 2016年第5期 76-88页

作者：黄琦陶建平华中农业大学经济管理学院湖北武汉430070

以秦巴山集中连片特困区为例,采用数据包络分析和区域差异分析方法,进行金融扶贫效率测度、形态分布及精准优化研究。研究表明:片区金融扶贫效率不足且区域差异大;金融扶贫的主要支撑为技术效率,技术进步层面的金融改革是提高秦巴山片... 详细信息

以秦巴山集中连片特困区为例,采用数据包络分析和区域差异分析方法,进行金融扶贫效率测度、形态分布及精准优化研究。研究表明:片区金融扶贫效率不足且区域差异大;金融扶贫的主要支撑为技术效率,技术进步层面的金融改革是提高秦巴山片区金融效率的核心路径,但部分县域与其市整体扶贫政策导向不同,应采取差异化金融扶贫策略。为提升片区金融扶贫效率,应根据潜力型、朝阳型、黄金型、夕阳型四种效率形态分布类型,以及金融资源投入目标值优化分析,采取精准的金融扶贫优化策略。

关键词：秦巴山片区扶贫精准扶贫策略小康社会目标

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