On the relationship of the viscoelastic functions of polymeric solids at different temperatures

NiTi shape memory alloy is an intelligent drive and awareness materials which develop very rapidly and is used in many fields in recent years, whose mechanical properties are not only related to chemical composition, but also closely related to the temperature. This article aims to study the NiTi shape memory alloy wire’s constitutive behavior coupled thermal and mechanical properties at different temperatures. By analyzing the results, the relationship of NiTi shape memory alloy between deformation and the restoring force at elevated temperature is obtained, thus providing a basis for the engineering design and simulation process of NiTi intelligent material.

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Solubility of Bismuth in Liquid Bi-S Based Free Cutting Steel

High Temperature Materials and Processes ◽

10.1515/htmp-2013-0047 ◽

2014 ◽

Vol 33 (2) ◽

pp. 187-191 ◽

Cited By ~ 1

Author(s):

Haitao Liu ◽

Weiqing Chen ◽

Wenying Li ◽

Yanchong Yu

Keyword(s):

Atmospheric Pressure ◽

Boiling Point ◽

Recovery Rate ◽

Equilibrium Partial Pressure ◽

Cutting Steel ◽

Different Temperatures ◽

Mn Content ◽

Increasing Temperature ◽

Relationship Of ◽

The Relationship

AbstractSolubility of bismuth in liquid Bi-S based free cutting steel was measured using a vapor-liquid equilibration method at 1540–1600 °C, and the recovery rate of bismuth in the steel with different temperatures under an atmospheric pressure was also measured. The results showed that the solubility of bismuth in liquid Bi-S based free cutting steel from experiment under a constant volume at 1540, 1560, 1580, and 1600 °C were 0.174, 0.181, 0.205, and 0.220 mass%, respectively, and the relationship of bismuth solubility vs. temperature could be expressed as lg[%Bi] = −6049/T + 2.572. Meanwhile, the solubility of bismuth increased with the increase of Mn content, but decreased with the increase of C content. The recovery of bismuth in this experiment reached a maximum when the temperature was at bismuth boiling point or so, and then it was decreased with the increase of temperature when the temperature was above 1560 °C, which might be attributed to the accelerating of bismuth evaporation that were caused by the increase of bismuth equilibrium partial pressure above the surface of the molten steel with increasing temperature.

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Characteristics Analysis and Testing of SMA Spring Actuator

Advances in Materials Science and Engineering ◽

10.1155/2013/823594 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Jianzuo Ma ◽

Haolei Huang ◽

Jin Huang

Keyword(s):

Shape Memory ◽

Load Capacity ◽

Output Displacement ◽

Output Force ◽

Characteristics Analysis ◽

Different Temperatures ◽

Sma Spring ◽

Increasing Temperature ◽

Relationship Of ◽

The Relationship

The biasing form two-way shape memory alloy (SMA) actuator composed of SMA spring and steel spring is analyzed. Based on the force equilibrium equation, the relationship between load capacity of SMA spring and geometric parameters is established. In order to obtain the characteristics of SMA spring actuator, the output force and output displacement of SMA spring under different temperatures are analyzed by the theoretical model and the experimental method. Based on the shape memory effect of SMA, the relationship of the SMA spring actuator's output displacement with the temperature, the stress and strain, the material parameters, and the size parameters is established. The results indicate that the trend of theoretical results is basically consistent with the experimental data. The output displacement of SMA spring actuator is increased with the increasing temperature.

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Thermoelectric Efficiency of Silicon–Germanium Alloys in Finite-Time Thermodynamics

Entropy ◽

10.3390/e22101116 ◽

2020 ◽

Vol 22 (10) ◽

pp. 1116 ◽

Cited By ~ 1

Author(s):

Patrizia Rogolino ◽

Vito Antonio Cimmelli

Keyword(s):

Thermal Conductivity ◽

Finite Time ◽

Silicon Germanium ◽

Finite Time Thermodynamics ◽

Thermoelectric Efficiency ◽

Thermoelectric Energy ◽

Different Temperatures ◽

Nonlinear Regression Method ◽

Relationship Of ◽

The Relationship

We analyze the efficiency in terms of a thermoelectric system of a one-dimensional Silicon–Germanium alloy. The dependency of thermal conductivity on the stoichiometry is pointed out, and the best fit of the experimental data is determined by a nonlinear regression method (NLRM). The thermoelectric efficiency of that system as function of the composition and of the effective temperature gradient is calculated as well. For three different temperatures (T=300 K, T=400 K, T=500 K), we determine the values of composition and thermal conductivity corresponding to the optimal thermoelectric energy conversion. The relationship of our approach with Finite-Time Thermodynamics is pointed out.

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The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽

10.1017/s0094837300025707 ◽

1980 ◽

Vol 6 (02) ◽

pp. 146-160 ◽

Cited By ~ 29

Author(s):

William A. Oliver

Keyword(s):

Critical Points ◽

Scleractinian Corals ◽

Convincing Evidence ◽

Early Triassic ◽

Rugose Corals ◽

History Of ◽

The Subject ◽

Relationship Of ◽

The Relationship ◽

Biologic Factors

The Mesozoic-Cenozoic coral Order Scleractinia has been suggested to have originated or evolved (1) by direct descent from the Paleozoic Order Rugosa or (2) by the development of a skeleton in members of one of the anemone groups that probably have existed throughout Phanerozoic time. In spite of much work on the subject, advocates of the direct descent hypothesis have failed to find convincing evidence of this relationship. Critical points are:(1) Rugosan septal insertion is serial; Scleractinian insertion is cyclic; no intermediate stages have been demonstrated. Apparent intermediates are Scleractinia having bilateral cyclic insertion or teratological Rugosa.(2) There is convincing evidence that the skeletons of many Rugosa were calcitic and none are known to be or to have been aragonitic. In contrast, the skeletons of all living Scleractinia are aragonitic and there is evidence that fossil Scleractinia were aragonitic also. The mineralogic difference is almost certainly due to intrinsic biologic factors.(3) No early Triassic corals of either group are known. This fact is not compelling (by itself) but is important in connection with points 1 and 2, because, given direct descent, both changes took place during this only stage in the history of the two groups in which there are no known corals.

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Skeletal elements of crinoid echinoderms: High-resolution structural and microanalytical results

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074768 ◽

1983 ◽

Vol 41 ◽

pp. 194-195

Author(s):

D. F. Blake ◽

L. F. Allard ◽

D. R. Peacor

Keyword(s):

High Resolution ◽

Marine Invertebrates ◽

Sea Urchins ◽

Structural Features ◽

Sea Stars ◽

High Resolution Tem ◽

Relationship Of ◽

The Relationship ◽

Insight Into

Echinodermata is a phylum of marine invertebrates which has been extant since Cambrian time (c.a. 500 m.y. before the present). Modern examples of echinoderms include sea urchins, sea stars, and sea lilies (crinoids). The endoskeletons of echinoderms are composed of plates or ossicles (Fig. 1) which are with few exceptions, porous, single crystals of high-magnesian calcite. Despite their single crystal nature, fracture surfaces do not exhibit the near-perfect {10.4} cleavage characteristic of inorganic calcite. This paradoxical mix of biogenic and inorganic features has prompted much recent work on echinoderm skeletal crystallography. Furthermore, fossil echinoderm hard parts comprise a volumetrically significant portion of some marine limestones sequences. The ultrastructural and microchemical characterization of modern skeletal material should lend insight into: 1). The nature of the biogenic processes involved, for example, the relationship of Mg heterogeneity to morphological and structural features in modern echinoderm material, and 2). The nature of the diagenetic changes undergone by their ancient, fossilized counterparts. In this study, high resolution TEM (HRTEM), high voltage TEM (HVTEM), and STEM microanalysis are used to characterize tha ultrastructural and microchemical composition of skeletal elements of the modern crinoid Neocrinus blakei.

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Studies on Leukemogenic and Sarcomagenic Viruses

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067777 ◽

1970 ◽

Vol 28 ◽

pp. 156-157

Author(s):

Leon Dmochowski

Keyword(s):

Electron Microscopy ◽

Electron Microscope ◽

Morphological Properties ◽

Mode Of Development ◽

Relationship Of ◽

The Relationship

Electron microscopy has proved to be an invaluable discipline in studies on the relationship of viruses to the origin of leukemia, sarcoma, and other types of tumors in animals and man. The successful cell-free transmission of leukemia and sarcoma in mice, rats, hamsters, and cats, interpreted as due to a virus or viruses, was proved to be due to a virus on the basis of electron microscope studies. These studies demonstrated that all the types of neoplasia in animals of the species examined are produced by a virus of certain characteristic morphological properties similar, if not identical, in the mode of development in all types of neoplasia in animals, as shown in Fig. 1.

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The relationship of IGE receptor topography to signaling activity in RBL-2H3 mast cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100085484 ◽

1991 ◽

Vol 49 ◽

pp. 236-237

Author(s):

J.R. Pfeiffer ◽

J.C. Seagrave ◽

C. Wofsy ◽

J.M. Oliver

Keyword(s):

Mast Cells ◽

Protein A ◽

Scattered Electron ◽

Ige Receptor ◽

Receptor Complexes ◽

Ige Binding ◽

Electron Imaging ◽

Small Clusters ◽

Relationship Of ◽

The Relationship

In RBL-2H3 rat leukemic mast cells, crosslinking IgE-receptor complexes with anti-IgE antibody leads to degranulation. Receptor crosslinking also stimulates the redistribution of receptors on the cell surface, a process that can be observed by labeling the anti-IgE with 15 nm protein A-gold particles as described in Stump et al. (1989), followed by back-scattered electron imaging (BEI) in the scanning electron microscope. We report that anti-IgE binding stimulates the redistribution of IgE-receptor complexes at 37“C from a dispersed topography (singlets and doublets; S/D) to distributions dominated sequentially by short chains, small clusters and large aggregates of crosslinked receptors. These patterns can be observed (Figure 1), quantified (Figure 2) and analyzed statistically. Cells incubated with 1 μg/ml anti-IgE, a concentration that stimulates maximum net secretion, redistribute receptors as far as chains and small clusters during a 15 min incubation period. At 3 and 10 μg/ml anti-IgE, net secretion is reduced and the majority of receptors redistribute rapidly into clusters and large aggregates.

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