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Black Hole Complementarity in Terms of the Outsider and Insider Perspectives
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作者 Eugene Terry Tatum 《Journal of Modern Physics》 2024年第2期184-192,共9页
A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation... A complementarity hypothesis concerning outsider and insider perspectives of a gargantuan black hole is proposed. The two thought experiments presented herein are followed by a brief discussion of a new interpretation of black hole interior “space-and-time-reversal”. Specifically, it is proposed that the “singularity” space of the black hole interior is time-like and the expansion time of the black hole interior is space-like. The resemblance of this new insider interpretation to our own expanding and redshifting big bang universe is compelling. 展开更多
关键词 Black holes Complementarity Cosmological Models Rh = ct Models Flat Space Cosmology Schwarzschild Cosmology Thought experiment Dark Energy Quantum Vacuum
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Experimental and numerical study of the effect of pulsatile flow on wall displacement oscillation in a flexible lateral aneurysm model 被引量:3
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作者 L.Z.Mu X.Y.Li +5 位作者 Q.Z.Chi S.Q.Yang P.D.Zhang C.J.Ji Y.He G.Gao 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2019年第5期1120-1129,共10页
This study experimentally and numerically investigated the effect of pulsatile flow of different frequencies and outflow resistance on wall deformation in a lateral aneurysm.A method for constructing a flexible aneury... This study experimentally and numerically investigated the effect of pulsatile flow of different frequencies and outflow resistance on wall deformation in a lateral aneurysm.A method for constructing a flexible aneurysm model was developed,and a self-designed piston pump was used to provide the pulsatile flow conditions.A fluid-structure interaction simulation was applied for comparison with and analysis of experimental findings.The maximum wall displacement oscillation increased as the pulsation frequency and outflow resistance increased,especially at the aneurysm dome.There is an obvious circular motion of the vortex center accompanying the periodic inflow fluctuation,and the pressure at the aneurysm dome at peak flow increased as the pulsatile flow frequency and terminal flow resistance increased.These results could explain why abnormal blood flow with high frequency and high outflow resistance is one of the risk factors for aneurysm rupture. 展开更多
关键词 LATERAL ANEURYSM in VITRO experiment PULSATILE flow wall DISPLACEMENT OSCILLATION Fluid-structure interaction simulation
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EXPERIMENT OF SHORT WAVE COMMUNICATION AND THE INVESTIGATION OF THE PROPAGATION BEARINGS BETWEEN THE GREAT WALL STATION AND XINXIANG 被引量:1
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作者 Sun Xianru and Li Zhongqin China Research Institute of Radio Wave Propagation, Xinxiang 453003 《Chinese Journal of Polar Science》 1990年第1期67-74,共8页
The distance from the Great Wall Station (62.2°S, 58.9°W) to Xinxiang (35.3°N, 113.8°E) is 16981 km. The path passes through the polar cap absorption region and the auroral absorption zone, and it ... The distance from the Great Wall Station (62.2°S, 58.9°W) to Xinxiang (35.3°N, 113.8°E) is 16981 km. The path passes through the polar cap absorption region and the auroral absorption zone, and it is across the equator.In this paper firstly the effects of short wave communication and usable time blocks and frequency ranges between the Antarctic Great Wall Station and Xinxiang from December 1985 to March 1986 are introduced. The comparison between the usable frequency ranges with the estimated MUF is made. The upper limit of frequency ranges of communication along the short great circle path basically agrees with the MUF but there is difference between them along the long great circle path.Secondly, the result of the propagation bearings experiment in January to February 1986 is introduced in more detail, The propagation along the great circle path from the Great Wall Station to Xinxiang is the main propagation mode. But the propagation along non great circle paths occurs at times between Great Wall Station and Xinxiang. The non great circle path propagation varies with time because the ionospheric absorption and other conditions which support the non great circle path propagation are the function of the time. So the courses of the non great circle path propagation may be different in the different time. The mechanism of the constructing non great circle path propagation has been analysed. We preliminarily think the main cause of propagation along non great circle path is the ground scatter. The stronger radialization of the side lobes of the antenna and the less absorption of the ionosphere contribute to forming non great circle path propagation. 展开更多
关键词 Communication experiment Great wall Station Xinxiang Station Propagation bearings.
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Did LIGO Really Detect Gravitational Waves?—The Existence of Electromagnetic Interaction Made the Experiments of LIGO Invalid 被引量:4
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作者 Xiaochun Mei Ping Yu 《Journal of Modern Physics》 2016年第10期1098-1104,共7页
The paper proves that due to the existence of electromagnetic interaction, the experiments of LIGO cannot detect gravitational waves. This is also the reason why Weber’s experiments of gravitational waves failed. In ... The paper proves that due to the existence of electromagnetic interaction, the experiments of LIGO cannot detect gravitational waves. This is also the reason why Weber’s experiments of gravitational waves failed. In fact, the formulas of general relativity that gravitational waves affect distances are only suitable for particles in vacuum. LIGO experiments are carried out on the earth. The laser interferometers are fixed on the steel pipes on the earth’s surface in the balanced state of electromagnetic force. Electromagnetic force is 10<sup>40</sup> times greater than gravity. Gravitational waves are too weak to overcome electromagnetic force and change the length of steel pipes. Without considering this factor, the design principle of LIGO experiment has serious problem. The experiments to detect gravitational waves should move to space to avoid the influence of electromagnetic interaction. Besides, LIGO experiments have the following problems. 1) No explosion source of gravitational waves is really founded. 2) The argument that the Einstein’s theory of gravity is verified is a vicious circle and invalid in logic. 3) The results of experiments cause sharp contradiction for the energy currents of gravitational waves. The difference reaches to 10<sup>24</sup> times and is unacceptable. 4) The method of numerical relativity causes great errors due to the existence of singularities. The errors are enlarged by the effect of butterfly due to the non-linearity of Einstein’s equation of gravity. 5) The so-called change of length 10<sup>-18</sup> m between two glasses of interferometers detected in the experiment exceeds the ability of current technique. This kind of precise has entered micro-scalar. The uncertain principle of quantum mechanics makes it impossible. The signs appeared in LIGO experiments are not caused by distance change. 6) LIGO experiments have not detected gravitational waves. What detected may be the signs of disturbances coming from the middle region between two laser interferometers. 展开更多
关键词 LIGO experiments Gravitational Waves General Relativity Electromagnetic interaction Laser interferometer Weber experiment Singularity Black holes
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Landscape Design of the Ming Dynasty Outer City Wall in Nanjing from the Perspective of Experience Tourism
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作者 YU Ziping 《Journal of Landscape Research》 2018年第6期134-136,共3页
Taking a section of the Ming Dynasty Outer City Wall from Xianhe Gate to Qilin Gate for example, this paper proposed the landscape design from the perspective of experience tourism, highlighted the wal, and took the b... Taking a section of the Ming Dynasty Outer City Wall from Xianhe Gate to Qilin Gate for example, this paper proposed the landscape design from the perspective of experience tourism, highlighted the wal, and took the beautiful environment and rich history and cultures of the Ming Dynasty Outer City Wall as the essential experience elements, to build cultural recreational corridors with the theme of "experiencing the Ming Dynasty culture", so that visitors will get unforgettable experience, tourism quality, popularity of the Ming Dynasty Outer City Wall as well as its cultural and educational significance will be further promoted. 展开更多
关键词 Experience TOURISM the Ming DYNASTY Outer City wall CULTURAL CORRIDOR LANDSCAPE
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The Theoretically Studies and Field Testing of Self-Insulation Exterior Wall in the Hot Summer and Cold Winter Zone
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作者 Huifang Yu Quanbiao Xu +2 位作者 Sanming Zhang Weijun Gao Jianfeng Xu 《Energy and Power Engineering》 2017年第10期654-686,共33页
The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation o... The energy efficiency design of the exterior wall in the buildings of the hot summer and cold winter zone of China should consider the heat prevention in summer and the heat insulation in winter. The self-insulation of the exterior?wall is a more feasible design to satisfy the energy efficiency of buildings in the?zone. However, the systematic research is urgently needed for the self-insulation of the exterior wall in the hot summer and cold winter zone of China. The paper tested the thermal performance of the common non-clay materials such as shale sintered hollow brick, sand autoclaved aerated concrete block, etc. by means of indoor experiments. The energy efficiency effect of the common materials was verified using dynamic calculation soft PKPM and several constitutions of exterior wall with different main bricks and insulation materials on the heat bridge were simulated, too. Besides, the tests of the thermal performance of exterior wall in real constructions were carried out to testify the practical effect of the recommended constitutions of exterior wall with different main bricks and insulation materials on the heat bridge. The conclusions are: the physical and thermal properties of the six non-clay wall material are better than the clay porous brick;the thermal performance of the non-clay brick can be improved obviously through the rational arrangement of the holes;shale sintered hollow brick after increasing the holes and rationalizing the hole arrangement and sand autoclaved aerated concrete block are recommended for buildings in the hot summer and cold winter area of China. The dynamic calculation results show that the thermal performances?of the non-clay materials are all satisfied with the energy efficiency;The heat transfer coefficient of the exterior wall with composition?③,?in which?the main wall was sand autoclaved aerated concrete block and the material on the heat bridge was sand autoclaved aerated concrete plate, is the smallest among the three recommended compositions. 展开更多
关键词 SELF-inSULATION EXTERIOR wall inDOOR experiments Dynamic Simulation Field Testing Hot SUMMER and COLD WinTER Zone
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The Role of Flow in Crisis Intervention and Emotional Counseling in Tree-Hole Rescue
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作者 WU Jiatong 《Psychology Research》 2022年第1期11-18,共8页
Flow is the experience of working full time and enjoying the flow of your life,regardless of the rewards,like a flowing stream of water.Based on the literature review,this paper discusses the role of flow in the actua... Flow is the experience of working full time and enjoying the flow of your life,regardless of the rewards,like a flowing stream of water.Based on the literature review,this paper discusses the role of flow in the actual rescue work,combined with the actual work of the rescue mission in the tree hole baby crisis intervention and emotional counseling and accompanying.The effect of flow intervention is positive.It can reduce the rumination of young tree hole babies and increase and enhance their sense of life meaning and subjective well-being.Since the term“Flow”is rarely used in the process of intervention,this paper also looks forward to the further application of flow intervention. 展开更多
关键词 flow experience crisis intervention ruminant thinking sense of meaning of life tree hole action
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Research on the mechanical properties of the reinforced materials of retaining wall
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作者 ZHU Yunfei 《International English Education Research》 2016年第4期72-72,共1页
The main research purpose of this paper is to study the mechanical properties of the sand gravel packing of the retaining wall under the creep condition of reinforced materials, in order to figure it out, Indoor physi... The main research purpose of this paper is to study the mechanical properties of the sand gravel packing of the retaining wall under the creep condition of reinforced materials, in order to figure it out, Indoor physical experiments were carried out. 展开更多
关键词 mechanical properties retaining wall enforced materials indoor physical experiments
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Subleading terms of thermodynamic quantities around static spherical black holes
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作者 李固强 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期66-69,共4页
The thermodynamic quantities for the gases of massless particles with spin s = 1/2, 1, 3/2, 2 around static spherical black holes are investigated by using the brick-wall method. The appearance of the spin-dependent s... The thermodynamic quantities for the gases of massless particles with spin s = 1/2, 1, 3/2, 2 around static spherical black holes are investigated by using the brick-wall method. The appearance of the spin-dependent subleading terms is demonstrated and the terms are shown to contain not only the linear and quadratic terms of the spins but also a zero-power terra of the spins. 展开更多
关键词 thermodynamic quantity brick-wall method Boulware vacuum state static spherical black holes
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Neural Network Approach for Estimating the Hole Damage in Drilling Process of Reactive Powder Concrete (RPC)
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作者 Annamaria Gisario Alberto Boschetto Francesco Veniali 《材料科学与工程(中英文版)》 2011年第3期304-313,共10页
关键词 神经网络模型 活性粉末混凝土 损伤程度 RPC 网络方法 工艺孔 钻井 估计
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THEORY OF THICK-WALLED SHELLS AND ITS APPLICATION IN CYLINDRICAL SHELL
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作者 房营光 潘纪浩 陈维新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第11期1055-1065,共11页
In this paper, a theory of thick-walled shells is established by means of Hellinger-Reissner's variational principle, with displacement and stress assumptions. The displacements are expanded into power series of t... In this paper, a theory of thick-walled shells is established by means of Hellinger-Reissner's variational principle, with displacement and stress assumptions. The displacements are expanded into power series of the thickness coordinate. Only the first four and the first three terms are used for the displacements parallel and normal to the middle surface respectively. The normal extruding and transverse shear stresses are assumed to be cubic polynomials and to satisfy the boundary stress conditions on the outer and inner surfaces of the shell. The governing equations and boundary conditions are derived by means of variational principle. As an example, a thick-walled cylindrical shell is disscussed with the theory proposed. Furthermore, a photoelastic experiment has been carried out, and the results are in fair agreement with the computations. 展开更多
关键词 thick-walled shell cylindrical shell normal extruding stress variational principle photoelastic experiment
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Research of precise pulse plasma arc powder welding technology of thin-walled inner hole parts 被引量:3
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作者 Li Zhanming Du Xiaokun +1 位作者 Sun Xiaofeng Song Wei 《China Welding》 EI CAS 2017年第3期57-62,共6页
The inner hole parts played an oriented or supporting role in engineering machinery and equipment,which are prone to appear surface damages such as wear,strain and corrosion. The precise pulse plasma arc powder weldin... The inner hole parts played an oriented or supporting role in engineering machinery and equipment,which are prone to appear surface damages such as wear,strain and corrosion. The precise pulse plasma arc powder welding method is used for surface damage repairing of inner hole parts in this paper. The working principle and process of the technology are illustrated,and the microstructure and property of repairing layer by precise pulse plasma powder welding and CO2 gas shielded welding are tested and observed by microscope,micro hardness tester and X-ray residual stress tester etc. Results showed that the substrate deformation of thin-walled inner hole parts samples by precise pulse plasma powder welding is relatively small. The repair layer and substrate is metallurgical bonding,the transition zones( including fusion zone and heat affected zone) are relatively narrow and the welding quality is good. It showed that the thin-walled inner hole parts can be repaired by this technology and equipment. 展开更多
关键词 PRECISE pulse plasma arc POWDER WELDinG thin walled inNER hole PARTS WELDinG repairing layer
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Wall Effect of Underwater Explosion Load Based on Wave Motion Theories 被引量:2
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作者 肖巍 姚熊亮 郭君 《China Ocean Engineering》 SCIE EI CSCD 2014年第5期587-598,共12页
Owing to the existence of the flow field boundary, the shock wave load near the boundary is different from the freefield shock wave load. In the present paper, the hull plate load subjected to underwater shock wave is... Owing to the existence of the flow field boundary, the shock wave load near the boundary is different from the freefield shock wave load. In the present paper, the hull plate load subjected to underwater shock wave is investigated based onwave motion theories; in addition, the experimental study of the hull plate load is carried out. According to the theoreticalanalysis of the hull plate pressure, we find that the hull plate pressure oscillates repeatedly and decays rapidly with timepassing, the maximum hull plate pressure is 2/(1+n) times the maximum free field pressure, where n is the ratio ofimpedance, and the impulse is much smaller than the free field impulse. Compared with the experimental study, thetheoretical results agree well with the experimental data. 展开更多
关键词 underwater explosion wave motion theories wall effect IMPEDANCE experiment
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Numerical investigation of particle deposition on converging slot-hole film-cooled wall 被引量:1
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作者 ZHOU Jun-hui ZHANG Jing-zhou 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2819-2828,共10页
Numerical research on the dilute particles movement and deposition characteristics in the vicinity of converging slot-hole(console) was carried out, and the effect of hole shape on the particle deposition characterist... Numerical research on the dilute particles movement and deposition characteristics in the vicinity of converging slot-hole(console) was carried out, and the effect of hole shape on the particle deposition characteristics was investigated. The EI-Batsh deposition model was used to predict the particle deposition characteristics. The results show that the console hole has an obvious advantage in reducing particle deposition in comparison with cylindrical hole, especially under higher blowing ratio. The coolant jet from console holes can cover the wall well. Furthermore, the rotation direction of vortices near console hole is contrary to that near cylindrical hole. For console holes, particle deposition mainly takes place in the upstream area of the holes. 展开更多
关键词 gas–solid flow particle deposition film-cooled wall converging SLOT FILM COOLinG hole numerical simulation
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Entropy of quantum field in toroidal black hole without brick wall 被引量:1
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作者 王波波 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期467-472,共6页
In this paper the entropy of a toroidal black hole due to a scalar field is investigated by using the DLM scheme. The entropy is renormalized to the standard Bekenstein-Hawking formula with a one-loop correction arisi... In this paper the entropy of a toroidal black hole due to a scalar field is investigated by using the DLM scheme. The entropy is renormalized to the standard Bekenstein-Hawking formula with a one-loop correction arising from the higher curvature terms of the gravitational action. For the scalar field, the renormalized Newton constant and two renormalized coupling constants in the toroidal black hole are the same as those in the Reissner-Nordstrom black hole except for other one. 展开更多
关键词 black hole entropy renormalization brick-wall model scalar field
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Simulation and Experiment on Workability for Cold Pressure Forming of Sheet Metal Part with Step Cross-section 被引量:3
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作者 LU Xianfeng LI Hufeng +1 位作者 ZHANG Yuerong ZHOU Yong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第2期161-165,共5页
In modem manufacturing, a new type of sheet metal part with step cross-section in both inner hole and outer edge is proposed. The traditional stamping separating processes can only produce sheet metal part with vertic... In modem manufacturing, a new type of sheet metal part with step cross-section in both inner hole and outer edge is proposed. The traditional stamping separating processes can only produce sheet metal part with vertical cross-section. According to the latest developing theory and potential of cold pressure forming: combination of pressure and cold forging, a new flow control forming of sheet metal(FCF) is excogitated based on blanking process of general stamping and combined with cold forging processes such as extrusion and coining, etc, which is aiming at the above-mentioned new type of sheet metal part. With utilization of this new process, the new type of sheet metal parts can be manufactured. In order to shorten the testing period, the numerical simulation was carried out by using DEFORM-3D software, and both deformation and mechanics rules were analyzed. Based on the simulation, both punching part and blanked parts of this new type were successfully developed. Then a new conception of optimal distance between the step walls of inner hole and outside edge was proposed and the design principle for its numerical value was inferred. Furthermore, a mold set for combination of stamping & cold forging was designed and manufactured, by which the technologic experiments were taken for validation with Aluminum plate of thickness 2.35 mm for power battery cover board, which verified the principle of the distance between the step walls. The research of cold pressure forming of thin sheet metal with step cross-section is significant, not only to the development of modem mechanical manufacture, but also to metal plastic forming science. 展开更多
关键词 sheet metal step cross-section numerical simulation distance between walls technologic experiment
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Experimental study on seismic behavior of semi-rigid connection between steel beam and concrete wall 被引量:2
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作者 刘爱民 周德源 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第1期129-137,共9页
Beam-column or beam-wall connections are an important problem in high-rise buildings. In this study, based on the analysis of an example structure, an analytical model for design of the semi-rigid connections between ... Beam-column or beam-wall connections are an important problem in high-rise buildings. In this study, based on the analysis of an example structure, an analytical model for design of the semi-rigid connections between steel beams and RC walls in high-rise hybrid buildings is proposed. Also, the mechanical characteristics of these connections subjected to low-reversed cyclic loading are investigated through comparison of experimental results from three semi-rigid connections and two rigid connections. Moreover, some latent problems for design of these connections as well as the corresponding solutions are discussed. The results from the experiments and analyses indicate that semi-rigid connections exhibit satisfactory capacity and seismic performance, and the proposed design can be used in practice. 展开更多
关键词 Key words high rise building hybrid structure BEAM wall connection seismic performance experiment study
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Seed and Wasp Production in the Mutualism of Figs and Fig Wasps 被引量:1
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作者 YaoJin-yan ZhaoNan-xian +3 位作者 ChenYi-zhu JiaXiao-cheng DengYuan YuHui 《Forestry Studies in China》 CAS 2005年第1期25-28,共4页
Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ov... Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait., we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity), in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However, at the male flower phase, production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating ones. This might be related with the weaker competition among wasps since bagged figs were not easy to reach by wasps from outside. 展开更多
关键词 FICUS Ficus wasp mutualism conflicts seed and wasp production Seed and Wasp Production in the Mutualism of Figs and Fig Wasps Yao Jin-yan1 2 Zhao Nan-xian1 Chen Yi-zhu1* Jia Xiao-cheng1 2 Deng Yuan1 2 Yu Hui1 2 1South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 P. R. China 2Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China ABSTRACT Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait. we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity) in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However at the male flower phase production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating
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Static inelastic analysis of RC shear walls
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作者 陈勤 钱稼茹 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2002年第1期94-99,共6页
A macro-model of a reinforced concrete (RC) shear wall is developed for static inelastic analysis.The model is composed of RC column elements and RC membrane elements.The column elements are used to model the boundary... A macro-model of a reinforced concrete (RC) shear wall is developed for static inelastic analysis.The model is composed of RC column elements and RC membrane elements.The column elements are used to model the boundary zone and the membrane elements are used to model the wall panel.Various types of constitutive relationships of concrete could be adopted for the two kinds of elements.To perform analysis,the wall is divided into layers along its height.Two adjacent layers are connected with a rigid beam.There are only three unknown displacement components for each layer.A method called single degree of freedom compensation is adopted to solve the peak value of the capacity curve.The post-peak stage analysis is performed using a forced iteration approach.The macro-model developed in the study and the complete process analysis methodology are verified by the experimental and static inelastic analytical results of four RC shear wall specimens. 展开更多
关键词 RC shear wall macro-model static inelastic analysis experiment
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Filling mode and regularity of vertical centrifugal casting process of titanium alloy in thin-walled cylinder cavity 被引量:3
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作者 Qin Xu Xing Wang +1 位作者 Yong-gang Guo Shi-ping Wu 《China Foundry》 SCIE 2019年第2期105-109,共5页
The mold filling process of titanium alloy in a thin-walled cylinder cavity under vertical centrifugal casting process was studied by means of the hydraulic simulation experiments. Results show that the filling mode o... The mold filling process of titanium alloy in a thin-walled cylinder cavity under vertical centrifugal casting process was studied by means of the hydraulic simulation experiments. Results show that the filling mode of the melt in the cylinder cavity varies with casting wall-thickness. When the casting wall-thickness is less than or equal to the thickness of the first layer during the filling process, the melts fill the cavity from the bottom to the top.When the casting wall-thickness is greater than the thickness of the first layer during the filling process, the melts first fill the largest radius parts of the cavity with a certain thickness of the first layer from the bottom to the top of the cavity, and then they fill the cavity from the larger radius part to the smaller radius part. The melt filling ability increases with the increment of the mold rotational speed and the pouring temperature. In another aspect, the melt filling ability rises with the decrement of the melt viscosity, and the melt with the better filling ability is prone to fill the cylinder cavity layer by layer. 展开更多
关键词 titanium alloy THin-wallED CASTinG vertical CENTRIFUGAL CASTinG cylinder-shape CAVITY hydraulic experiment mold FILLinG
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