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    题名 作者 年代 出处 被引量
1一种服务聚合中QoS全局最优服务动态选择算法显示文摘Web服务作为一种新型的Web应用模式,近年来得到了迅速的发展.如何动态地把现存的各种Web服务整合起来以形成新的、满足不同用户需求的、增值的复杂服务已成为新的应用需求和研究热点.针对现有服务聚合中服务选择技术的不足,提出了一种解决服务聚合中服务动态选择QoS全局最优化问题的实现算法GODSS(global optimal of dynamic Web services selection).算法的主要思想是把服务动态选择全局最优化问题转化为一个带QoS约束的多目标服务组合优化问题,利用多目标遗传算法的智能优化原理,通过同时优化多个目标函数,最终产生一组满足约束条件的Pareto优化服务聚合流程集.理论分析和实验结果说明了算法的可行性和有效性.刘书雷 刘云翔 张帆 唐桂芬 景宁 2007软件学报2007,18,3:146
2动态对比增强MRI的应用与进展显示文摘定量MRI不仅能提供组织器官的基本结构信息,也能提供病变发生发展过程中丰富的生物学和病理生理学信息,是目前国际MRI应用研究的热点。动态对比增强(dynamic contrast-enhanced, DCE)-MRI是一种非常有价值的定量MRI技术,在临床研究中发挥了较大作用。因获得的病理生理信息受成像设备、成像技术、分析方法及患者个体差异的影响,其结果变异较大,临床应用有一定的挑战性,其潜能亟须开发。卢光明 2015中华放射学杂志2015,49,6:45
3Estimation of internal nutrient release in large shallow Lake Taihu, China显示文摘Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, China, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition),both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in sediments.As for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4+-N for whole lake is ca. 10,000 ton/a, and PO43--P is ca. 900 ton/a. In the dynamic condition, nutrient release following sediment suspension was estimated according to three different intensities of wind forcing which were defined as 'calm' (wind speed is less than 2 m/s), 'gentle' (wind speed is greater than 2 m/s and less than 6 m/s) and 'gust' (wind speed is greater than 6 m/s). The release rate in the condition of 'calm' was estimated in terms of the nutrient release in the laboratory experimental static condition; whereas the release rate in conditions of 'gentle' and 'gust' was estimated in terms of measurement during sediment resuspension conducted in flume experiments. With the observation of wind velocity and frequency in 2001, each type of wind forcing took the frequency of 12%, 82% and 6% for 'calm', 'gentle' and 'gust', respectively. The yearly release of nitrogen was 81,000 ton and phosphorus was 21,000 ton, which is about 2-6 folds of annual external loading, respectively.QIN Boqiang, ZHU Guangwei, ZHANG Lu, LUO Liancong, GAO Guang & GU Binhe Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Everglades Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL 33406, USA 2006Science China Earth Sciences2006,49,z1:37
4基于撬棒并联动态电阻的自适应双馈风力发电机低电压穿越显示文摘当电网故障引起电压跌落时,为防止大装机容量风电场的风机脱网,双馈风力发电机(DFIG)多采用Crowbar电路来实现低电压穿越(LVRT)。传统Crowbar电路采用固定阻值的电阻,很难兼顾对转子电流和直流母线电压的抑制以及对Crowbar的投入工作时间的控制。针对传统Crowbar的不足提出了一种基于Crowbar并联动态电阻的双馈风力发电机低电压穿越方案,制定了该方案的自适应控制策略以及其阻值的整定方法。仿真分析不同跌落深度下所提方案的LVRT特性,并与改变IGBT的导通脉宽的变电阻Crowbar方案进行了比较,结果表明带并联动态电阻Crowbar方案的LVRT效果较好,不仅兼顾了对转子过电流和直流母线过电压的抑制,而且在电压深度跌落时可缩短Crowbar的投入时间,有利于系统电压的恢复。张曼 姜惠兰 2014电工技术学报2014,29,2:37
5Delayed hepatocarcinogenesis through antiangiogenic intervention in the nuclear factor-kappa B activation pathway in rats显示文摘BACKGROUND:The active form of nuclear factor-kappa B(NF- κB)is involved in the initiation,generation,and development of hepatocellular carcinoma(HCC),and is up-regulated in inflammation-associated malignancies.We investigated the dynamic expression of NF-κB and its influences on the occurrence of HCC through antiangiogenic(thalidomide) intervention in NF-κB activation. METHODS:Hepatoma models were induced with 2-fluorenyl- acetamide(2-FAA,0.05%)in male Sprague-Dawley rats,and thalidomide(100 mg/kg body weight)was administered intragastrically to intervene in NF-κB activation.The pathological changes in the liver of sacrificed rats were assessed after hematoxylin and eosin staining.NF-κB mRNA was amplified by RT-nested PCR.The alterations of NF-κB and vascular endothelial growth factor(VEGF)expression were analyzed by enzyme-linked immunosorbent assay,immunohistochemistry,and Western blotting. RESULTS:Rat hepatocytes showed denatured,precancerous,and cancerous stages in hepatocarcinogenesis,with an increasing tendency of hepatic NF-κB,NF-κB mRNA,and VEGF expression,and their values in the HCC group were higher than those in controls(P<0.001).In the thalidomide- treated group,the morphologic changes generated only punctiform denaturation and necrosis at the early or middle stages,and nodular hyperplasia or a little atypical hyperplasia at the final stages,with the expression of NF-κB (χ2=9.93,P<0.001)and VEGF(χ2=8.024,P<0.001)lower than that in the 2-FAA group. CONCLUSION:NF-κB is overexpressed in hepatocarcinogenesis and antiangiogenic treatment down-regulates the expression of NF-κB and VEGF,and delays the occurrence of HCC.Dong, Zhi-Zhen Yao, Deng-Fu Wu, Wei Yao, Min Yu, Hong-Bo Shen, Jun-Jun Qiu, Li-Wei Yao, Ning-Hua Sai, Wen-Li Yang, Jun-Ling 2010Hepatobiliary & Pancreatic Diseases International2010,9,2:31
6DYNAMIC RECOVERY AND DYNAMIC RECRYSTALLIZATION OF 7005 ALUMINIUM ALLOY DURING HOT COMPRESSION显示文摘Dynamic recovery and dynamic recrystallizatin behaviors of AA7005 aluminium alloy (Al - Zn - Mg) during hot compression are investigated by isothermal compression testing.The interdependence of flow stress,stress, strain rate,true strain and deformation temperature for the alloy is analyzed by introduc- ing Zener-Hollomon parameter. A steady - state flow of the 7005 alloy is confirmed to be a thermal- ly activated process.which is governed by rate-controlling mechanisms of dislocations.A hyperbolic sine relationship can satisfactorily correlate temperature, strain rate with flow stress through an Arrhe- nius term that involves thermal activation parameters. The dynamic recovery mechanisms of the alloy are discussed.Cross- slip of jogged screw dislocations is the main dynamic recovery mechanism over the deformation temperatures and strain rates.Subgrains are highly developed in the originally elongat- ed grains.The size of the subgrain increases with decrease of the natural logarithm of Zener- Hol - lomon parameter.Local dynamic recrystallization is operative when the alloy is deformed at temperature of 500℃ and strain rate of 0. 001s - 1.J. Shen S. S. Xie and J. H. tang (General Research Institute for Non - ferrous Metals,Beijing 100088, China) 2000Acta Metallurgica Sinica(English Letters)2000,13,1:33
7湖泊水动力模型外部输入条件不确定性和敏感性分析显示文摘以我国典型的大型浅水湖泊太湖为研究区域,采用国内外常用的环境流体动力学模型(EFDC),结合拉丁超立方取样(LHS)方法,研究湖泊水动力模型中4个重要的外部输入条件,即3个边界输入条件(出入湖流量、风速、风向)和1个初始输入条件(初始水位),对模型水动力模拟结果(水位、水龄以及流场)的影响与贡献.结果表明,初始水位的设定对模拟全湖水位和水龄产生决定性影响,不确定性的贡献率分别达到85.73%.和1166.125%,对垂向平均流速影响的贡献率只有3%;风速对表面流速模拟结果影响较大,贡献率达到58.70%,而对水位和水龄的贡献率分别为5.25%和3.00%.在垂向上,各层流速受外部输入条件不确定性的影响规律相似,贡献率排序为风速(55%-60%)〉风向(10%-15%)〉初始水位≈出入湖流量(1%~5%).因此在模拟大型浅水湖泊水动力过程时,可以根据不同的输出目标能够有针对性地提高外部输入条件的准确度,为提高模型精确度提供有效信息.李一平 邱利 唐春燕 布旻晟 田威 余钟波 Kumud Acharya 2014中国环境科学2014,34,2:30
8Quantitative analysis of hepatic hypoxia-inducible factor-1α and its abnormal gene expression during the formation of hepatocellular carcinoma显示文摘BACKGROUND:Hepatic hypoxia-inducible factor-1(HIF-1) is activated in the progression of hepatocellular carcinoma (HCC).This study aimed to investigate the dynamic alterations of HIF-1αand its gene expression so as to explore the relationship between HIF-1αexpression and hepatocarcinogenesis at the early stage of HCC. METHODS:A hepatoma model was made with 2-fluorenyl- acetamide(2-FAA)in male Sprague-Dawley rats.Morphological changes of rat hepatocytes were assessed pathologically (HE staining).The dynamic expression of hepatic and circulating HIF-1αwas quantitatively analyzed by ELISA. The gene fragments of hepatic HIF-1αmRNA were amplified by RT-PCR and confirmed by sequencing.The cellular distribution of hepatic HIF-1αexpression was confirmed by immunohistochemistry. RESULTS:Histological examination confirmed granulelike degeneration to atypical hyperplasia and HCC development in rat hepatocytes and progressive increases in the levels of hepatic and circulating HIF-1αand its gene expression during the course.The levels of HIF-1α expression in the liver and blood of rats with hepatoma were significantly higher than those in normal ratsand those with degeneration.Immunohistochemical analysis confirmed the positive expression and hepatocyte distribution of HIF-1αin the development of rat hepatoma. A positive relationship was found between HIF-1α expression in the liver and blood(P<0.01). CONCLUSIONS:The above observations support the hypothesis that the overexpression of HIF-1αand its gene are closely associated with the malignant transformation of hepatocytes and play an important role at the stage of hepatocarcinogenesis.Deng-Fu Yao,Hua Jiang,Min Yao,Yue-Ming Li,Wen-Jing Gu,Yu-Cheng Shen, Li-Wei Qiu,Wei Wu,Xin-Hua Wu and Wen-Li Sai Research Center of Clinical Molecular Biology,Department of Laboratory Science,and Department of Oncology,Affiliated Hospital of Nantong University,Nantong 226001, China Third Department of Medicine,Jiaonan People’s Hospital,Jiaonan 266400,China 2009Hepatobiliary & Pancreatic Diseases International2009,8,4:28
9Episodic rifting of continental marginal basins and tectonic events since 10 Ma in the South China Sea显示文摘Integrated study on the tectonic, basin filling and thermal evolution of the Tertiary basins on the northern margin of the South China Sea has indicated that the rift continental margin on the northern South China Sea is not a passive margin and that the western margin is characteristic of the transformextension. Episodic rifting and the thermal events since 10 Ma in the area have been documented by the integrated analysis of dynamic process. It has been clarified that the tectono-thermal events have exerted a significant influence on basin features and hydrocarbon accumulation, and particularly, the westward collision of the Lusong Island Arc, the generation of densely spaced faults in the Pearl River Mouth Basin, the rapid subsidence, high heat flow and large-scale over pressure and thermal-fluid breakthrough in the Yinggehai and the Qiongdongnan basins have proved to be the important factors determining the formation of oil and gas in these basins.Sitian Li Changsong Lin Qiming Zhang Shigong Yang Peikan Wu 1999Chinese Science Bulletin1999,44,1:27
10Nonlinear balance constraints in 3DVAR data assimilation显示文摘In many applications of 3DVAR, the balance constraints can be considered via two main approaches: weak constraint method which adds penalty terms to the cost function; and proper defi- nition of the background error covariance matrix with non-zero cross-correlation sub-matrices. The weak constraint approach requires determining the weighting matrices of the penalty terms. The background error covariance approach does not require determining those additional weighting ma- trices. However, it is only applicable to those linear or linearized balance constraints. A novel ap- proach is proposed based on the background error covariance approach by generalizing the so-called Derber-Bouttier formulation. An assimilation experiment of estimating temperature and salinity from the sea surface dynamic height observation is given to illustrate the proposed treatments of nonlinear balance constraints.ZHU Jiang YAN Changxiang 2006Science China Earth Sciences2006,49,3:24
11A comprehensive physical pattern of land-air dynamic and thermal structure on the Qinghai-Xizang Plateau显示文摘According to the boundary layer observations of three stations (Garze, Damxung and Qamdu) and relevant earth satellite, radiosonde and surface observations during the intensive observational period (IOP) of the second Tibetan (Qinghai-Xizang) Plateau Experiment of atmospheric science (TIPEX), the land-air physical process and dynamic model on the Tibetan Plateau were comprehensively analyzed in this study. The dynamic characteristics of boundary layer and the rules of turbulent motion on the plateau were illustrated. The characteristics of distributions of wind speed and direction with mutiple-layer structure and deep convective mixed layer on the plateau, the strong buoyancy effect in turbulent motion on the plateau on which the air density is obviously smaller than on the plain, and the Ekman spiral and its dynamic pump effect of the plateau deep boundary layer have been found. The local static distribution of water vapor and the horizontal advection of water vapor in the plateau boundary layer were studied. The abnomal thermodynamic structure on the plateau surface and boundary layer, including the plateau strong radiation phenomenon and strong heating source characteristics of the middle plateau, was also analyzed. The authors synthesized the above dynamic and thermodynamic structures of both surface and boundary layers on the plateau and posed the comprehensive physical model of the turbulence and convective mixture mechanism on the plateau boundary layer. The characteristics of formation, development and movement for convective cloud cluster over the plateau influencing floods in the Yangtze River area of China were studied. The conceptual model of dynamic and thermodynamic structures of turbulent motion and convective plume related to the frequent occurrence of 'pop-corn-like' cloud system is given as well.徐祥德 卞林根 李诗明 索朗多吉 周明煜 张光智 张宏升 王继志 陈家宜 刘辉志 赵翼俊 2002Science China Earth Sciences2002,45,7:24
12Assessment and sequencing of air target threat based on intuitionistic fuzzy entropy and dynamic VIKOR显示文摘In view of the fact that traditional air target threat assessment methods are difficult to reflect the combat characteristics of uncertain, dynamic and hybrid formation, an algorithm is proposed to solve the multi-target threat assessment problems. The target attribute weight is calculated by the intuitionistic fuzzy entropy(IFE) algorithm and the time series weight is gained by the Poisson distribution method based on multi-times data. Finally,assessment and sequencing of the air multi-target threat model based on IFE and dynamic Vlse Kriterijumska Optimizacija I Kompromisno Resenje(VIKOR) is established with an example which indicates that the method is reasonable and effective.ZHANG Kun KONG Weiren LIU Peipei SHI Jiao LEI Yu ZOU Jie 2018Journal of Systems Engineering and Electronics2018,29,2:24
13Rock burst mechanism analysis in an advanced segment of gob-side entry under different dip angles of the seam and prevention technology显示文摘In order to investigate the frequent occurrences of rock burst in gob-side entry during the mining process of the mining zone No. 7, the mechanical model of main roof of fully-mechanized caving mining before breaking was established by the Winkler foundation beam theory, and the stress evolution law of surrounding rock with different dip angles of the seam during the mining process was analyzed by using FLAC3 D. The results show that: with the dip angle changing from 45° to 0°, the solid-coal side of gobside entry begins to form an L-shaped stress concentration zone at a dip angle of 30°, and the stress concentration degree goes to higher and higher levels. However, the stress concentration degree of the coalpillar side goes to lower and lower levels; the influence range and peak stress of the abutment at the lateral strata of adjacent gob increase with dip angle decreasing and reach a maximum value at a dip angle of 0°, but the tailgate is not affected; the abutment pressure superposition of two adjacent gobs leads to stress concentration further enhancing in both sides of gob-side entry. With the influence of strong mining disturbance, rock burst is easily induced by dynamic and static combined load in the advanced segment of gob-side entry. To achieve stability control similar to that in the roadway, the key control strategy is to reinforce surrounding rock and unload both sides. Accordingly, the large-diameter drilling and high-pressure water injection combined unloading and reinforced support cooperative control technology was proposed and applied in field test. The results of Electromagnetic Emission(EME) and field observation showed that unloading and surrounding rock control effect was obvious.Yang Zengqiang Liu Chang Tang Shichuan Dou Linming Cao Jinglong 2018International Journal of Mining Science and Technology2018,28,6:24
14Analysis of sensitivity and errors in Maglev vibration test system显示文摘In order to improve work performance of M aglev vibration test systems,the relationships of operating parameters between different components and system were researched. The working principle of photoelectric displacement sensor was analyzed. The relationship between displacement of transducer and the infrared light area received by sensor was given. The method of expanding the dynamic range of vibrator was proposed,which makes dynamic range of Maglev vibrator doubled. By increasing the amplification of the amplifier,the sensitive photoelectric displacement sensor can be maintained. Two modes of operation of the controller were analyzed. Bilateral work of vibration test system designed can further improve the stability of the system.An object vibration was measured by Maglev vibration test system designed when different vibration exciter frequencies were loaded. Experiments showthat the output frequency measured by Maglev vibration test system and loaded are the same. Finally,the errors of test system were analyzed. These errors of vibration test system designed can meet the requirements of application. The results laid the foundation for the practical application of magnetic levitation vibration test system.JIANG Dong LIU Xukun WANG Deyu YANG Jiaxiang 2016Instrumentation2016,3,1:24
15DEVELOPMENT OF POLYMER MINERAL COMPOSITE AND ITS DAMPING PROPERTY显示文摘The principle of production of polymer mineral composite was analyzed. Property parameters and the procedure for producing PMC components were also given. Damping property and principle of vibration absorption of polymer mineral composite were also investigated. Reduced experiment was conducted for two jigs which are similar in structure only different in material that one made of PMC the other made of casting iron to test their dynamic characteristic.J.Sun 1) ,J.F.Li 2) ,B.J.Lu 1) ,J.F.Zhong 3) and X.P. Huang 1) 1) Dept. of Agri. Eng., Laiyang Agriculture College, Laiyang 265200,China 2) Dep. of Mech. Eng., Shandong University of Technology, Jinan 250061,China 3) Agruculture S 1999Acta Metallurgica Sinica(English Letters)1999,12,5:23
16腰椎后路椎间融合术后椎间融合的X线片及三维CT评价显示文摘目的 探讨X线片和三维CT(3D-CT)在判定单节段后路腰椎椎间融合术后椎间融合情况的临床价值.方法 选取接受后路腰椎椎间融合术并随访1年以上的患者43例,男19例,女24例;年龄16~74岁,平均47.2岁.峡部裂性滑脱21例,退变性滑脱15例,腰椎间盘突出并不稳症3例,腰椎间盘突出症复发3例,极外侧椎间盘突出症1例.单纯骨粒植骨26例,骨粒加椎间融合器17例.单节段内固定24例,双节段内固定19例.均为单节段椎间融合,其中L3,4,6例,L4,5,17例,L5 S1 20例.应用改良Brantigan评分判定腰椎正侧位X线片及3D-CT扫描所示椎间融合程度;动力位X线片判断椎间稳定性.结果 随访12~85个月,平均18个月.末次随访时X线片及3D-CT所示椎间融合率分别为64%(28/43例)和40%(17/43例).3D-CT的Brantigan评分小于正侧位X线片(P<0.05).根据诊断、固定节段及融合方式不同分组,各组3D-CT评分均低于正侧位X线片(P<0.05).动力位X线片示椎间不稳定者仅3例(7%).结论 腰椎3D-CT能更准确地评价椎间融合情况.拆除内固定前进行3D-CT检查非常必要.拆除内固定前摄动力位X线片对判定椎体间融合的临床意义不大.郑燕平 刘新宇 贾龙 王延国 黎君彦 2009中华骨科杂志2009,29,12:22
17基于DSR的改性沥青及混合料动态黏弹性能显示文摘为了在相似加载条件下比较改性沥青及混合料的动态黏弹性能,选择4种不同特点的改性沥青,成型了混合料小梁试件.应用动态剪切流变仪(DSR)分别进行了不同温度下的频率扫描试验,根据时间-温度等效原理构建了改性沥青及混合料的流变主曲线,对主曲线形态和流变模型拟合结果进行了对比分析.研究表明:改性沥青及混合料的复数剪切模量主曲线形态相似,采用改进型CAM模型进行拟合的效果很好,相关系数在0.996以上;平衡复数剪切模量G*e可用来区分不同类型改性沥青及其混合料的高温性能;高强改性沥青的高温抗车辙性能明显优于其他改性沥青,但软化点和60℃动力黏度不适用于评价高强改性沥青.改性沥青的动态力学响应能够反映其混合料的黏弹性能.郭咏梅 倪富健 2014东南大学学报(自然科学版)2014,44,2:22
18Island partition of the distribution system with distributed generation显示文摘In this paper, a novel optimum island partition model based on Tree Knapsack Problem (TKP) is presented for the distribution system integrated with distributed generation (DG), and a Depth-first Dynamic Programming Algorithm (DPA) is used to solve this model. With the considerations of the load priority, controlled/uncontrolled loads, and the constraints of power balance, voltage and equipment capacity, the model can meet the practical engineering requirements very well. The island partition problem of the distribution system integrated with multiple DGs is first decomposed into multiple TKPs, each of which is solved by DPA respectively. Then, the initial optimum island partition scheme is gained through an island combination procedure, and the final island partition scheme is obtained after feasibility checking and adjustment. Since the algorithm proposed owns the advantages of strong theoretical foundation and low computational complexity, it can find the approximate optimal solution within a limited time. The results of examples demonstrate the validity of the new model and algorithm.WANG XuDong & LIN JiKeng* Key laboratory of Power System Simulation and Control of Ministry of Education, Tianjin University, Tianjin 300072, China 2010Science China(Technological Sciences)2010,53,11:21
19Chebyshev Fitting Way and Error Analysis for Propeller Atlas across Four Quadrants显示文摘A Chebyshev fitting way for a propeller atlas across four quadrants is discussed. As an example, Chebyshev polynomialfitting results and its error analysis are given. Because it’s difficult generally to get a propeller atlas across four quadrants,a wayis used to construct an alternative with higher accuracy based on the properties. As an application example, an alternative forthe propeller property of a Deep Submergence Vebicle across four quadrants is given practically and a simulation model ofLI Dian-pu, WANG Zong-yi, CHI Hai-hong College of Automation , Harbin Engineering University, Harbin 150001, China 2002Journal of Marine Science and Application2002,1,1:20
20Experimental study on dynamic mechanical property of cemented tailings backfill under SHPB impact loading显示文摘Cemented tailings backfill(CTB) have increasingly been used in recent years to improve the stability of mining stopes in deep underground mines. Deep mining processes are often associated with rock bursting and high-speed dynamic loading conditions. Therefore, it is important to investigate the characteristics and dynamic mechanical behavior of CTB. This paper presents the results of dynamic tests on CTB specimens with different cement and solid contents using a split Hopkinson pressure bar(SHPB). The results showed that some CTB specimens exhibited one to two lower stress peaks after reaching dynamic peak stress before they completely failed. The greater the cement-to-tailings ratio is, the more obvious the strain reaction. This property mainly manifested as follows. First,the dynamic peak stress increased with the increase of the cement-to-tailings ratio when the impact velocity was fixed. Second, the dynamic peak stress had a quadratic relationship with the average stress rate. Third, the cement-to-tailings ratio could enhance the increase rate of dynamic peak stress with strain rate. In addition, the dynamic strength enhancement factor K increased with the increase of strain rate, and its value was larger than that of the rock samples. The failure modes of CTB specimens under low-speed impact were tensile failure and X conjugate shear failure, where were nearly the same as those under static uniaxial and triaxial compression. The CTB specimens were crushed and broken under critical strain, a failure mode similar to that of low-strength concrete. The results of the experimental research can improve the understanding of the dynamic mechanical properties of CTB and guide the strength design of deep mining backfills.Yu-ye Tan Xin Yu Davide Elmo Lin-hui Xu Wei-dong Song 2019International Journal of Minerals,Metallurgy and Materials2019,26,4:19
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