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The mechanisms of thermal solidification agent promoting steam diversion in heavy oil reservoirs
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作者 Zhan-Xi Pang Qian-Hui Wang +2 位作者 Qiang Meng Bo Wang Dong Liu 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1902-1914,共13页
At high cycles of steam huff&puff,oil distribution in reservoirs becomes stronger heterogeneity due to steam channeling.Thermal solidification agent can be used to solve this problem.Its solution is a lowviscosity... At high cycles of steam huff&puff,oil distribution in reservoirs becomes stronger heterogeneity due to steam channeling.Thermal solidification agent can be used to solve this problem.Its solution is a lowviscosity liquid at normal temperature,but it can be solidified above 80℃.The plugging degree is up to 99%at 250℃.The sweep efficiency reaches 59.2%,which is 7.3%higher than pure steam injection.In addition,simultaneous injection of viscosity reducer and/or nitrogen foams can further enhance oil recovery.The mechanism of this technology depends on its strong plugging ability,which changes the flowing pattern of steam to effectively mobilize remaining oil.Viscosity reducer and nitrogen foams further expand the sweep range and extends the effective period.Therefore,thermal solidification agent can plug steam channeling paths and adjust steam flowing direction to significantly enhance oil recovery at high cycles of steam huff&puff. 展开更多
关键词 Heavy oil reservoir Steam huff&puff Steam channeling Steam diversion Plugging performance mechanism analysis
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Mechanical mechanism analysis of tension type anchor based on shear displacement method 被引量:18
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作者 肖淑君 陈昌富 《Journal of Central South University of Technology》 EI 2008年第1期106-111,共6页
Based on the fact that the shear stress along anchorage segment is neither linearly nor uniformly distributed, the load transfer mechanism of the tension type anchor was studied and the mechanical characteristic of an... Based on the fact that the shear stress along anchorage segment is neither linearly nor uniformly distributed, the load transfer mechanism of the tension type anchor was studied and the mechanical characteristic of anchorage segment was analyzed. Shear stress?strain relationship of soil surrounding anchorage body was simplified into three-folding-lines model consisting of elastic phase, elasto-plastic phase and residual phase considering its softening characteristic. Meanwhile, shear displacement method that has been extensively used in the analysis of pile foundation was introduced. Based on elasto-plastic theory, the distributions of displacement, shear stress and axial force along the anchorage segment of tension type anchor were obtained, and the formula for calculating the elastic limit load was also developed accordingly. Finally, an example was given to discuss the variation of stress and displacement in the anchorage segment with the loads exerted on the anchor, and a program was worked out to calculate the anchor maximum bearing capacity. The influence of some parameters on the anchor bearing capacity was discussed, and effective anchorage length was obtained simultaneously. The results show that the shear stress first increases and then decreases and finally trends to the residual strength with increase of distance from bottom of the anchorage body, the displacement increases all the time with the increase of distance from bottom of the anchorage body, and the increase of velocity gradually becomes greater. 展开更多
关键词 ANCHOR anchorage segment tension type ELASTO-PLASTICITY mechanical analysis shear displacement method residual strength
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MECHANISM DESIGN AND MOTION ANALYSIS OF A SPHERICAL MOBILE ROBOT 被引量:17
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作者 Zhan Qiang Jia Chuan +1 位作者 Ma Xiaohui Zhai Yutao 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2005年第4期542-545,共4页
A new spherical mobile robot BHQ-1 is designed. The spherical robot is driven by two internally mounted motors that induce the ball to move straight and turn around on a fiat surface. A dynamic model of the robot is d... A new spherical mobile robot BHQ-1 is designed. The spherical robot is driven by two internally mounted motors that induce the ball to move straight and turn around on a fiat surface. A dynamic model of the robot is developed with Lagrange method and factors affecting the driving torque of two motors are analyzed. The relationship between the turning radius of the robot and the length of two links is discussed in order to optimize its mechanism design. Simulation and experimental results demonstrate the good controllability and motion performance of BHQ-1. 展开更多
关键词 Spherical mobile robot mechanism design Motion analysis
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Mechanism Analysis of Stiffness Improvement by Waterborne Epoxy Resin Surface Sizing Agent 被引量:5
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作者 Hui Xu ShuMei Wang +1 位作者 YuanYuan Li HongQi Dai 《Paper And Biomaterials》 2016年第1期44-50,共7页
Low-basis-weight paper lacks normal strength and stiffness. Waterborne epoxy resin could be employed with oxidized starch to improve paper stiffness through surface sizing. In this study,the mechanism of enhancing sti... Low-basis-weight paper lacks normal strength and stiffness. Waterborne epoxy resin could be employed with oxidized starch to improve paper stiffness through surface sizing. In this study,the mechanism of enhancing stiffness by adding waterborne epoxy resin was fully investigated. The results indicated that through surface sizing with epoxy resin,the paper thickness was preserved,whereas the elastic modulus increased significantly and the epoxy resin had positive impact on single fiber strength. A rigid resin layer and interpenetrating polymer network formed on the surface and in the inner layer of the paper,respectively. The formed resin layer and interpenetrating polymer network strongly supported the paper,leading to the improvement of the elastic modulus and stiffness. The stiffness improvement through surface sizing was mainly due to the formation of a fibrous composite layer and penetration of the sizing agent into the inner layers of the paper. The better the combination between fiber and sizing agent,the higher were the elastic modulus and the stiffness of the whole paper. 展开更多
关键词 surface sizing STIFFNESS mechanism analysis waterborne epoxy resin
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Analysis of Frequency Characteristics and Sensitivity of Compliant Mechanisms 被引量:7
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作者 LIU Shanzeng DAI Jiansheng +3 位作者 LI Aimin SUN Zhaopeng FENG Shizhe CAO Guohua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第4期680-693,共14页
Based on a modified pseudo-rigid-body model,the frequency characteristics and sensitivity of the large-deformation compliant mechanism are studied.Firstly,the pseudo-rigid-body model under the static and kinetic condi... Based on a modified pseudo-rigid-body model,the frequency characteristics and sensitivity of the large-deformation compliant mechanism are studied.Firstly,the pseudo-rigid-body model under the static and kinetic conditions is modified to enable the modified pseudo-rigid-body model to be more suitable for the dynamic analysis of the compliant mechanism.Subsequently,based on the modified pseudo-rigid-body model,the dynamic equations of the ordinary compliant four-bar mechanism are established using the analytical mechanics.Finally,in combination with the finite element analysis software ANSYS,the frequency characteristics and sensitivity of the compliant mechanism are analyzed by taking the compliant parallel-guiding mechanism and the compliant bistable mechanism as examples.From the simulation results,the dynamic characteristics of compliant mechanism are relatively sensitive to the structure size,section parameter,and characteristic parameter of material on mechanisms.The results could provide great theoretical significance and application values for the structural optimization of compliant mechanisms,the improvement of their dynamic properties and the expansion of their application range. 展开更多
关键词 compliant mechanism pseudo-rigid-body model frequency characteristic sensitivity analysis finite element analysis
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Analysis of Dissociation Mechanism of CO_2 in a Micro-Hollow Cathode Discharge 被引量:1
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作者 程将领 王海兴 孙素蓉 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第10期153-157,共5页
Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk... Considering the feature of distributions of parameters within the micro-hollow cathode discharge, we use a simple method to separate the sheath region characterized by drastic changes of plasma parameters and the bulk plasma region characterized by smooth changes of plasma parameters. A zero-dimensional chemical kinetic model is used to analyze the dissociation mechanism of CO2 in the bulk plasma region of a micro-hollow cathode discharge and is validated by comparisons with previous modeling and experimental results. The analysis of the chemical kinetic processes has shown that the electron impact dissociation and heavy species impact dissociation are dominant in different stages of the rnicro-hollow cathode discharge process for a given applied voltage. The analysis of energy consumption distributions under different applied voltages reveals that the main reason of the conversion improvement with the increase of the applied voltage is that more input energy is distributed to the heavy species impact dissociation. 展开更多
关键词 of on is MHCD analysis of Dissociation mechanism of CO2 in a Micro-Hollow Cathode Discharge in CO
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Analysis and Design of the Globoidal Indexing Cam Mechanism 被引量:3
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作者 FU Yan ming School of Mechanical and Electronic Engineering and Automation, Shanghai University, Shanghai 200072, China 《Advances in Manufacturing》 2000年第1期54-59,共6页
We first design and analyze the contour surface of the globoidal indexing cam with the aid of computer, and then do optimum design according to the requirements of dynamics. Finally, we discuss the problem of the pres... We first design and analyze the contour surface of the globoidal indexing cam with the aid of computer, and then do optimum design according to the requirements of dynamics. Finally, we discuss the problem of the pressure angle of the globoidal indexing cam mechanism in detail and put forward a new concept of equivalent pressure angle. 展开更多
关键词 globoidal indexing cam analysis of cam mechanism design of cam mechanism dynamics of mechanism pressure angle
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Analysis of fluoxetine-induced plasticity mechanisms as a strategy for understanding plasticity related neural disorders 被引量:1
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作者 Francesco Mattia Rossi 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第4期547-548,共2页
Fluoxetine hydrochloride,better known for its commercial name Prozac,is one of the most widely prescribed antidepressant drugs all over the world.This drug was considered a"breakthrough drug"for the treatment of dep... Fluoxetine hydrochloride,better known for its commercial name Prozac,is one of the most widely prescribed antidepressant drugs all over the world.This drug was considered a"breakthrough drug"for the treatment of depression because of its very high selectivity as a serotonin reuptake inhibitor and because it presented a lower side-effectprofile than previous drugs (Wong et al., 2005). 展开更多
关键词 analysis of fluoxetine-induced plasticity mechanisms as a strategy for understanding plasticity related neural disorders
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Application of Task-Oriented Method of Serial Robot for Mechanism Analysis and Evaluation
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作者 Zhi-Juan Sun Jing Zhao Li-Ming Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2014年第2期13-20,共8页
Revealing the relations among robotic comprehensive performance,configuration,scales and working tasks is the basis to optimize robotic mechanism. Due to the correlation and diversity of the single performance indexes... Revealing the relations among robotic comprehensive performance,configuration,scales and working tasks is the basis to optimize robotic mechanism. Due to the correlation and diversity of the single performance indexes,statistical principles of linear dimension reduction and nonlinear dimension reduction are introduced into comprehensive performance analysis and evaluation for typical serial robot. The robotic mechanism's configuration,scales and task with the best comprehensive performance can be obtained by principal component analysis( PCA) and kernel principal component analysis( KPCA) respectively. The results show that KPCA can reveal the nonlinear relations among different single performance indexes more effectively and provide more comprehensive performance information than PCA. Thus,task-oriented method of serial robot for mechanism analysis and evaluation is proposed,which also provides scientific research basis for the mechanism synthesis and optimum task order. 展开更多
关键词 serial robot mechanism analysis mechanism synthesis optimum task PCA KPCA
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AUTOMATIC DISPLACEMENT ANALYSIS OF PLANAR MECHANISMS WITH MATCHING BASIC KINEMATIC CHAINS METHOD
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作者 WangYuxin MuXihui 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2003年第2期113-116,共4页
A simple, efficient, automatic and universal method to fulfill displacementanalysis of a great deal of mechanisms regenerated by Yan's mechanism creative theory has beendeveloped. For a regenerated mechanism, at f... A simple, efficient, automatic and universal method to fulfill displacementanalysis of a great deal of mechanisms regenerated by Yan's mechanism creative theory has beendeveloped. For a regenerated mechanism, at first, the method identifies its type and structure andchanges it into a rigid structure by fixing the ground link and the input link. And then this rigidstructure is decomposed into a set of basic kinematic chains (BKCs). By matching the type of BKC,the displacement analysis equations can be set up, and all possible configurations, in whichpositions of all movable links are considered, can be given out. 展开更多
关键词 mechanism analysis computerized method matching basic kinematic chains
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THE ANALYSIS OF MECHANISM OF IMPACT OF AEROSOLS ON EAST ASIAN SUMMER MONSOON INDEX AND ONSET
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作者 沈新勇 黄文彦 陈宏波 《Journal of Tropical Meteorology》 SCIE 2017年第4期357-367,共11页
RegCM4.3, a high-resolution regional climate model, which includes five kinds of aerosols(dust, sea salt,sulfate, black carbon and organic carbon), is employed to simulate the East Asian summer monsoon(EASM) from 1995... RegCM4.3, a high-resolution regional climate model, which includes five kinds of aerosols(dust, sea salt,sulfate, black carbon and organic carbon), is employed to simulate the East Asian summer monsoon(EASM) from 1995 to 2010 and the simulation data are used to study the possible impact of natural and anthropogenic aerosols on EASM.The results show that the regional climate model can well simulate the EASM and the spatial and temporal distribution of aerosols. The EASM index is reduced by about 5% by the natural and anthropogenic aerosols and the monsoon onset time is also delayed by about a pentad except for Southeast China. The aerosols heat the middle atmosphere through absorbing solar radiation and the air column expands in Southeast China and its offshore areas. As a result, the geopotential height decreases and a cyclonic circulation anomaly is generated in the lower atmosphere. Northerly wind located in the west of cyclonic circulation weakens the low-level southerly wind in the EASM region. Negative surface radiative forcing due to aerosols causes downward motion and an indirect meridional circulation is formed with the low-level northerly wind and high-level southerly wind anomaly in the north of 25° N in the monsoon area, which weakens the vertical circulation of EASM. The summer precipitation of the monsoon region is significantly reduced,especially in North and Southwest China where the value of moisture flux divergence increases. 展开更多
关键词 aerosol climate effect regional climate model East Asian summer monsoon monsoon index onset time indirect circulation mechanism analysis
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Mechanism Analysis of " 7·21" Extremely Heavy Rainstorm Process in 2012 in Beijing
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作者 Mao Weiping Yan Yan +1 位作者 Wang Tingfang Zhang Youshu 《Meteorological and Environmental Research》 CAS 2015年第1期4-8,共5页
Extremely heavy rainstorm occurred in Beijing on July 21,2012, which was the most serious since 1961. Based on analyzing the precipitation characteristics, formation mechanism of the rainstorm process was analyzed. Re... Extremely heavy rainstorm occurred in Beijing on July 21,2012, which was the most serious since 1961. Based on analyzing the precipitation characteristics, formation mechanism of the rainstorm process was analyzed. Results showed that when the precipitation process occurred, it was stable east-high and west-low situation at 500 hPa, and there was a steady stream of water vapor transportation at middle and low layers and strong vertical ascending motion at 700 hPa. The distribution of physical quantity field (relative humidity, vorticity and divergence) showed that they were all benefited to the formation of rainstorm. Then, falling zone of rainstorm and the movement of rain belt, generation, development and weakening of precipitation were analyzed. Finally, according to circulation situation and the distribution of physical quantity at each layer, vertical distribu- tion of physical quantity and distribution of water vapor and jet stream, "7 · 21" rainstorm model was summarized. 展开更多
关键词 Extremely heavy rainstorm mechanism analysis Rainstorm model China
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Dynamics analysis on transverse cutting mechanism of straw checkerboard paving robot
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作者 Yu Ye ShuFa Sun JinHao Liu 《Research in Cold and Arid Regions》 2012年第5期439-445,共7页
The transverse cutting mechanism of the checkerboard paving robot, which directly affects the robot's operation, is regarded as the most important part in a transverse pavement system This research aims at designing ... The transverse cutting mechanism of the checkerboard paving robot, which directly affects the robot's operation, is regarded as the most important part in a transverse pavement system This research aims at designing a new system which is appropriate for desert wofidng en- vironments and finishing cutting the rope of straw. In this paper, computer emulating technology is applied, and with three-dimensional modeling by Pro/ENGINEER software, can observe whether or not interference exists. Also, the speed and displacement parameters of the main parts of the cutting system are given by the dynamic emulation by Automatic Dynamic Analysis of Mechanical System (ADAMS), which theoretically assures the feasibility and appropriateness of the cutting mechanisrn~ Finally, results of the experinaent shows that the cutting mechanism can cut the straw strand as designed. 展开更多
关键词 straw checkerboard cutting mechanism dynamic analysis Automatic Dynamic analysis of Mechanical System
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KINEMATIC ANALYSIS OF THE GENERAL SPATIAL 7R MECHANISM
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作者 陈惟荣 卢醒庸 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1989年第10期933-945,共13页
The displacement, velocity and acceleration analysis of the general spatial 7R mechanism is discussed in this paper, fused on the method proposed in Ref. [2], an input-output algebra equation of the 16th degree in the... The displacement, velocity and acceleration analysis of the general spatial 7R mechanism is discussed in this paper, fused on the method proposed in Ref. [2], an input-output algebra equation of the 16th degree in the tan-half-angle of the output angular displacement is derived. The derivation process and computation are considerably simple. A program written in Allanguage is used to derive the coefficients of displacement equations: therefore the amount of manual work is greatly decreased. The results are verified by a numerical example. The researches of this paper and Ref. [5]found a base for establishing an expert system of spatial mechanism analysis in the future. 展开更多
关键词 KINEMATIC analysis OF THE GENERAL SPATIAL 7R mechanism LISP LINK
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Sulfur poisoning mechanism of three way catalytic converter and its grey relational analysis
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作者 蔡皓 刘亚飞 +3 位作者 龚金科 鄂加强 耿玉鹤 余立平 《Journal of Central South University》 SCIE EI CAS 2014年第11期4091-4096,共6页
Combining a detailed catalytic surface reaction mechanism with noble metal and promoter elementary reactions, a new three-way catalytic converter(TWC) reaction mechanism is established. Based on the new mechanism, ste... Combining a detailed catalytic surface reaction mechanism with noble metal and promoter elementary reactions, a new three-way catalytic converter(TWC) reaction mechanism is established. Based on the new mechanism, steady condition numerical simulation is carried out, and the change of light-off temperatures and conversion efficiency with various SO2 contents is obtained. By grey relational analysis(GRA), the relational grade between conversion efficiency and SO2 content is obtained. And, the result shows that SO2 content has the most important influence on C3H6 and NOX conversion efficiency. This provides an important reference to the improvement of activity design of TWC, and may provide guidance for the condition design and optimization of TWC. 展开更多
关键词 sulfur poisoning three-way catalytic converter reaction mechanism numerical simulation grey relational analysis
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An analysis on the formation mechanism of the distributionof high content of chlorophyll-a in the continentalshelf edge waters of East China Sea
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作者 Fei Zunle First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第1期97-107,共11页
On the basis of the data obtained from the comprehensive Kuroshio surveys in 1987-1988,this paper analyses the oceanographic characteristics in the area (125°-130° E,27°-31° N) of the continental s... On the basis of the data obtained from the comprehensive Kuroshio surveys in 1987-1988,this paper analyses the oceanographic characteristics in the area (125°-130° E,27°-31° N) of the continental shelf edge of the East China Sea (E. C. S. ) and its adjacent waters and discusses the effects of the Kuroshio front,thermocline and upwelling of the Kuroshio subsurface water on the distribution of standing stock of phytoplankton (chlorophyll-a). The distribution of high content of chlorophylly-a has been detected at 20-50 in depth in the water body on the left side of the Kuroshio front in the continental shelf edge waters of the E. C. S. The high content of chlorophyll-a spreads from the shelf area to the Kuroshio area in the form of a tongue and connects with the maximum layer of subsurface chlorophyll-a of the Kuroshio and pelagic sea. The author considers that the formation of the distribution of high content chlorophyll-a in this area results from the bottom topography and oceanic environment and there are close correlations between the high content of chlorophyll-a and the light-nutrient environment. 展开更多
关键词 Ph Th An analysis on the formation mechanism of the distributionof high content of chlorophyll-a in the continentalshelf edge waters of East China Sea HIGH
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A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone
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作者 Zhang Qiuqing and Ding Yihui 1. National Research Center for Marine. Environment Forecasts, Beijing 100081, China2. Academy of Meteorological Science, State Meteorological Administration, Beijing 100081, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第4期525-535,共11页
A diagnostic study is performed in the paper on the process of typhoon Norris (1980) transforming into an ex-tratropical cyclone after its landing over Southeast China. The main findings are as follows:The changes of ... A diagnostic study is performed in the paper on the process of typhoon Norris (1980) transforming into an ex-tratropical cyclone after its landing over Southeast China. The main findings are as follows:The changes of kinetic energy are mainly attributed to the generation due to non-divergent wind. During the early stage of the typhoon landing, there exits only a small quantity of kinetic energy exchanging with the environment. And after it is transformed into an extratropical cyclone, a large amount of kinetic energy is exported from the system toward the environment.The horizontal and vertical flux-divergence terms of eddy available potenlial energy are the prominent sinks in the budgets of eddy kinetic energy. The generations of eddy kinetic energy due to both the barotropic and baroclinic processes are source terms. The former is remarkable during the initial stage. But after the depression is transformed into an extratropical cyclone, the roles of the generation by the barotropic and baroclinic processes are reversed, 1. e. , the latter has become more significant than the former.Diabatic heating is the most dominant heat source. The terms of vertical heat flux by cumulus and large-scale motion are the major sinks. And the latter is prominent after the system is transformed into an extratropical cycfone. 展开更多
关键词 A preliminary analysis of physical mechanism of transformation process from a landed typhoon into an extratropical cyclone
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Revealing the contribution of basilar membrane's biological activity to the mechanism of the cochlear phonosensitive amplification
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作者 J.Y.LIANG Wenjuan YAO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第5期823-840,共18页
Explaining the mechanism of the cochlear active phonosensitive amplification has been a major problem in medicine.The basilar membrane(BM)is the key infrastructure.In 1960,Nobel Laureate von B′ek′esy first discovere... Explaining the mechanism of the cochlear active phonosensitive amplification has been a major problem in medicine.The basilar membrane(BM)is the key infrastructure.In 1960,Nobel Laureate von B′ek′esy first discovered BM's traveling wave motion.Since that time,BM's models only have considered the traveling wave but not the biological activity.Therefore,a new model considering changes of BM's stiffness in space and time is established based on the immersed boundary method to describe its biological activity.It not only reproduces the results of traveling wave motion but also explains the mechanization on the generation of traveling wave.An important discovery is that changes of BM's stiffness in space and time will cause the unstable global resonance,which will induce amplification of sounds in cochlea.An important inference is that biological activity shall be included in the application of mechanical principles to the analysis of life,which is the essential difference between biomechanics and general mechanics. 展开更多
关键词 basilar membrane(BM) biological activity mechanical analysis cochlear phonosensitive amplification
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Experimental Study and Failure Criterion Analysis of Rubber Fibre Reinforced Concrete under Biaxial Compression-Compression
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作者 Yanli Hu Peiwei Gao +2 位作者 Furong Li Zhiqing Zhao Zhenpeng Yu 《Journal of Renewable Materials》 SCIE EI 2023年第4期2055-2073,共19页
In order to examine the biaxial compression-compression properties of rubber fibre reinforced concrete(RFRC),an experimental study on RFRC under different lateral compressive stresses was carried out by considering di... In order to examine the biaxial compression-compression properties of rubber fibre reinforced concrete(RFRC),an experimental study on RFRC under different lateral compressive stresses was carried out by considering different rubber replacement rates and polypropylene fibre contents.The failure modes and mechanical property parameters of different RFRC working conditions were obtained from the experiment to explore the effects of rubber replacement rate and polypropylene fibre content on the biaxial compression-compression properties of RFRC.The following conclusions were drawn.Under the influence of lateral compressive stress,the biaxial compression-compression failure mode gradually developed from a columnar pattern to a flaky pattern,suggesting that the incorporation of rubber and polypropylene fibres into the concrete resulted in a significant change in the development of cracks.For different rubber replacement rates and polypropylene fibre contents,the vertical compressive stress exhibited the same developing trend under the influence of lateral compressive stress.Specifically,the lateral compressive stress imposed the minimum effect on the vertical compressive stress when the rubber replacement rate and polypropylene fibre content were 20%and 0.4%,respectively,and imposed the maximum effect when the rubber replacement rate and polypropylene fibre content were 20%and 0%,respectively.With the increase of rubber replacement rate,the vertical peak stress was significantly reduced,which implies that an appropriate amount of polypropylene fibres can increase the vertical peak stress to a certain extent.Then,the biaxial compression-compression mechanism of RFRC was analysed from the microscopic level by using scanning electron microscope(SEM).Meanwhile,based on Kupfer’s biaxial compression-compression failure criterion and the octahedral stress space,a biaxial compression-compression failure criterion for RFRC was proposed,which was proven to have good applicability.The research results of this study provide important theoretical basis for the engineering application and development of RFRC. 展开更多
关键词 Rubber fibre reinforced concrete(RFRC) biaxial compression-compression mechanical properties mechanism analysis failure criterion
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The Mechanism Analysis of Solar Energy Origin
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作者 WU Zhimin 《Aerospace China》 2020年第2期39-46,共8页
Why has the sun burnt for billions of years? What is the mechanism of combustion? What will happen to the trend of solar combustion? Modern humans have only just begun their close-up exploration of the sun. By studyin... Why has the sun burnt for billions of years? What is the mechanism of combustion? What will happen to the trend of solar combustion? Modern humans have only just begun their close-up exploration of the sun. By studying the sun, we can learn more about other stars. The more we understand other stars, the more we will know about the universe in the end. The exploration of the origin of solar energy will help people to deepen their understanding of the origin of the universe as well as the development of the universe. Solar probes will help us further understand the characteristics of the sun, validate relevant theories and make new discoveries. 展开更多
关键词 solar structure energy origin mechanism analysis PROBE
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