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951.
The cohesive behavior of aerated solids controls fluidization behavior of bulk materials. Very cohesive materials cannot be easily fluidized. However, aeration is often used in contact bed situations to help maintain some cohesive materials in flowable conditions. The cohesive properties of aerated materials are not well understood. This paper presents a new test method to measure the effect of aeration on cohesive flow properties. These measurements could be used along with new design equations to predict arching and stable rathole formation of cohesive materials in aerated process equipment. Experimental results on fine silica powder and fluid catalytic cracking (FCC) catalyst show the evolution of the yield locus shape and the effective yield locus shape as a function of the degree of aeration. It was found that both the cohesion intercept and the yield locus slope are functions of the degree of aeration. 相似文献
952.
Lukosiute I. Levinskas R. Sapragonas J. Kviklys A. 《Mechanics of Composite Materials》2004,40(2):151-158
Composite structures consisting of an epoxy resin matrix filled with a porous perlite containing a finely dispersed polyvinyl chloride are investigated. Models of the composites are analyzed in which the formation of a transition layer between the filler particles and the matrix may arise as a result of interaction between the separate components. The influence of the perlite and plasticized polyvinyl chloride particles on epoxy composite characteristics, such as the bending, tensile, impact, and adhesion strengths, are studied. 相似文献
953.
Analysis of the fiber length dependence of its strength by using the weakest-link approach 2. Analysis of test data 总被引:1,自引:0,他引:1
A method for estimating the model parameters is described, the results found in processing glass, flax, and carbon fiber and
carbon bundle datasets are reported, and a comparison of different models is given.
Translated from Mekhanika Kompozitnykh Materialov, Vol. 45, No. 1, pp. 65–74, January–February, 2008. 相似文献
954.
对130MeV 3He+natAg→110,112In和890以及714MeV 84Kr+27Al →111In反应中的核耗散行为进行了一个比较分析. 数据分析建议除了已知的温度和/或形变依赖性以外, 核耗散强度可能对角动量也存在一定的依赖性. 相似文献
955.
Yu. Paramonov J. Andersons M. Kleinhofs A. Paramonova 《Mechanics of Composite Materials》2008,44(4):389-396
The possibility of using a unified mathematical model, based on the theory of Markov chains, to describe the distribution
of the conditional fatigue limit at a fixed number of loading cycles and the residual strength of a specimen after cyclic
loading is demonstrated. Numerical examples are presented.
__________
Translated from Mekhanika Kompozitnykh Materialov, Vol. 44, No. 4, pp. 559–568, July–August, 2008. 相似文献
956.
Thesdg interacting boson model (sdgIBM), which includes monopole (s), quadrupole (d) and hexadecupole (g) degrees of freedom, enables one to analyze hexadecupole (E4) properties of atomic nuclei. Various aspects of the model, both analytical and numerical, are reviewed emphasizing the
symmetry structures involved. A large number of examples are given to provide understanding and tests, and to demonstrate
the predictiveness of thesdg model. Extensions of the model to include proton-neutron degrees of freedom and fermion degrees of freedom (appropriate for
odd mass nuclei) are briefly described. A comprehensive account ofsdgIBM analysis of all the existing data on hexadecupole observables (mainly in the rare-earth region) is presented, includingβ
4 (hexadecupole deformation) systematics,B(IS4; 0
GS
+
→4
γ
+
) systematics that give information about hexadecupole component in γ-vibration,E4 matrix elements involving few low-lying 4+ levels,E4 strength distributions and hexadecupole vibrational bands in deformed nuclei.
The survey of literature for this review was concluded in December 1991. 相似文献
957.
Collision strengths for all the transitions between the 15 lowest states of neon-like Ni XIX have been calculated for electron
impact in the 80–140 Ry energy range. Configuration-interaction wavefunctions have been used to represent the target states.
The standardR-matrix code has been used to calculate the lower scattering partial waves (L≤9), while a no-exchange version of the same code has been used to compute efficiently the higher partial waves (L≥10). Effective collision strengths for 105 excitation transitions between the ground state 2s
22p
6
1
S
e and the 142s
22p
53l Rydberg states are tabulated for electron temperatures in the range logT=5.40 to logT=7.00, withT expressed in °K. 相似文献
958.
Ahmed Jalal Uddin Norihiro Katayama Yutaka Ohkoshi Yasuo Gotoh Masanobu Nagura 《Journal of Polymer Science.Polymer Physics》2002,40(21):2449-2462
For monofilament biodegradable sutures fabricated from the L ‐lactide–ε‐caprolactone (75/25) copolymer [P(LLA/CL)], there have been some concerns regarding their mechanical properties, such as the knot‐pull strength and stiffness. This article demonstrates the further potentiality of these sutures through improvements in those properties. With the aim of diminishing the molecular orientation, particularly in the suture surface region, we adopted an expedient method to treat P(LLA/CL) sutures with an acetone/water mixture, using different times and time patterns. The changes in the molecular orientation distributions across the suture cross sections were characterized by the specific index of birefringence measured with an interference microscope. The crystal orientations, knot‐pull strengths, tensile strengths, and bending rigidity were measured. The conformational changes in suture breaking during knot‐pull tests were analyzed with high‐speed‐video observations. Morphological analyses of the fractural surfaces were performed with scanning electron microscopy. The knot‐pull strength tended to rise, in comparison with that of untreated samples, up to a certain treatment time and was accompanied by a minimal decrement of the tensile strength. The knot‐pull strength did not show an increasing trend with further treatment, whereas the tensile strength declined remarkably. The birefringence, crystal orientation, bending rigidity, fractured surface analysis, and high‐speed‐video observations revealed molecular disorientation mainly in the filament outer layers for that particular treatment causing the sutures to be considerably softer. The suture softness played a role in changing the deformation behavior of the knot when a load was applied and caused the knot‐pull strength to rise. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 2449–2462, 2002 相似文献
959.
湿敏陶瓷感湿机理的新模型讨论 总被引:3,自引:0,他引:3
本讨论了湿敏陶瓷感湿机理比较接近于实际的“镶嵌模型”,对“镶嵌模型”的线性方程进行了求解,并对结果进行了分析,为各种多孔陶瓷湿敏元件的开发提供了新途径。 相似文献
960.
LY—12铝高温屈服强度的测量 总被引:1,自引:0,他引:1
本文介绍LY-12铝合金在常温至400℃动载下(应变率为 10~3/秒),屈服强度的测试及研究。采用一维Hopkinson压杆实验装置及管式高温炉。利用一维应力波传播理论及应变片直接测量两种方法,得到了LY-12铝合金的屈服强度随温度变化的曲线。 相似文献