The Relationship of Radiation Embrittlement and Swelling for Austenitic Steels for WWER Internals

2009 ◽  
Author(s):  
B. Z. Margolin ◽  
I. P. Kursevich ◽  
A. A. Sorokin ◽  
V. S. Neustroev
Keyword(s):  
Phase Transformation ◽  
Austenitic Steel ◽  
Sharp Decrease ◽  
Austenitic Steels ◽  
Radiation Swelling ◽  
Temperature Dependences ◽  
Temperature Ranges ◽  
Radiation Conditions ◽  
Relationship Of ◽  
The Relationship

To investigate the effect of swelling upon mechanical properties of irradiated austenitic steel the investigations were conducted with steel 18Cr-10Ni-Ti and its weld irradiated up to same damage doses in two different temperature ranges: at the irradiation temperature of 330÷340°C when swelling is practically absent and at 400÷450°C when a considerable swelling level of 3÷13% is observed. Basing on the investigation results the temperature dependences of tensile properties of irradiated metal were constructed and analyzed. Fracture surfaces for ruptured specimens were examined by SEM. Comparative investigations of magnetization of irradiated metal at different irradiation temperatures were performed. It was concluded from the performed analysis of the results that in highly irradiated austenitic steel with considerable swelling a ductile to brittle transition is observed, which is caused of the Feγ→Feα phase transformation. The investigations of magnetization of metals with different swelling, as well as on the available literature data confirm a possibility of the Feγ→Feα phase transformation under considerable radiation swelling. The criterion is proposed allowing one to determine the radiation conditions under which the Feγ→Feα transformation make it possible a brittle fracture. The mechanism resulting in a sharp decrease of the ultimate tensile strength of highly irradiated metal is considered.

The Temperature Dependence of CO2 Production of the North American Lizards Cnemidophorus velox and Sceloporus undulatus

1986 ◽  
Vol 7 (4) ◽  
pp. 347-351
Author(s):  
Deborah K. Anderson ◽  
Ann M. Sweet ◽  
Richard G. Bowker
Keyword(s):  
Temperature Dependence ◽  
Individual Variability ◽  
Co2 Production ◽  
Sceloporus Undulatus ◽  
The North ◽  
Daily Energy ◽  
Temperature Ranges ◽  
Relationship Of ◽  
The Relationship ◽  
Activity Times

AbstractThe relationship of body temperature and resting CO2 production was examined for the lizards Cnemidophorus velox and Sceloporus undulatus. The CO2 production of both species was characterized by broad temperature ranges (30-38°C) in which no temperature dependence of CO2 production was observed. Also, both species showed considerable betwee individual variability. The metabolic rate of the widely foraging species, C. velox, is significantly higher than that of the wait-and-ambush species S. undulatus. However, this difference is eliminated when the size of the animals and activity times are considered; both species then have similar estimated average daily energy costs.

Inner Connection of Bainite and Pearlite Transformation in Steels

2014 ◽  
Vol 900 ◽  
pp. 64-67
Author(s):  
Jian Hao Chen ◽  
Xiao Ling· Zhou ◽  
Lan Meng ◽  
Wen Liu
Keyword(s):  
Magnetic Field ◽  
Phase Transformation ◽  
Driving Force ◽  
Spontaneous Magnetization ◽  
Martensite Phase ◽  
Bainite Transformation ◽  
Relationship Of ◽  
The Relationship ◽  
New Phase ◽  
Magnetic Drive

Decomposition of austenite in steels from high to low temperatures is pearlite, bainite and martensite phase transformation. According to studies, magnetic field promotes the three transformations. The phenomenons indicate the three transformations have coherence in magnetics. There is a transformation from paramagnetism (γ) to ferromagnetism (α) among all these three. Magnetic drive ΔGm plays an important role in the phase transition. The bainite transformation was carried out at 300°C during different isothermal time. Combining the results, it studied the relationship of bainite and pearlite transformation from characteristics of the nucleation of BF, microstructures etc. Even without magnetic field, spontaneous magnetization makes contributions to phase transformation driving force. Small deflections cause by spontaneous magnetization may promote the lattice reorganization from FCC to BCC in a certain extent, while promote the formation of the new phase with BCC cube.

scholarly journals Textured Sr2Sc0.1Nb0.1Co1.5Fe0.3O6−2δ Thin Film Cathodes for IT-SOFCs

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 777
Author(s):  
Zhaoxin Zhu ◽  
Chuan Zhou ◽  
Wei Zhou ◽  
Nan Yang
Keyword(s):  
Thin Film ◽  
Solid Oxide Fuel Cells ◽  
Operating Temperature ◽  
Reduction Reaction ◽  
Cathode Side ◽  
Temperature Ranges ◽  
Chemical States ◽  
Orr Activity ◽  
Relationship Of ◽  
The Relationship

Reducing the operating temperature of solid oxide fuel cells (SOFCs) to intermediate (650–850 °C) or even lower levels (400–650 °C) is an important practical requirement. However, the main obstacle to lowering the operating temperature is the poor oxygen reduction reaction (ORR) activity on the cathode side and, therefore, it is essential to explore cathode materials with good ORR activity in these temperature ranges. In this work, we investigated the possibility of using Sr2Sc0.1Nb0.1Co1.5Fe0.3O6−2δ (SSNCF) as a suitable intermediate temperature cathode material. SSNCF thin films with different orientations were prepared using the pulsed laser deposition technique, and the relationship of the surface chemical states and ORR activity was discussed in terms of crystallographic orientation. The results showed that the SSNCF/YSZ grown along the [110] direction exhibited superior ORR activity compared to the SSNCF/SDC/YSZ thin film electrode grown along the [100] direction. This was explained by the variation in the Sr-surface enrichment and cobalt ion oxidation state using X-ray photoemission spectroscopy.

Electrical Conductivity in Alkali Iron Phosphate Glasses

2008 ◽  
Vol 368-372 ◽  
pp. 1446-1448 ◽  
Author(s):  
Tong Wei Li ◽  
Zheng Xin Tang ◽  
Wei Wei Ju ◽  
Xiao Yang Gong
Keyword(s):  
Activation Energy ◽  
Arrhenius Equation ◽  
Iron Phosphate ◽  
Phosphate Glasses ◽  
Arrhenius Behavior ◽  
Exponential Factor ◽  
Temperature Ranges ◽  
Iron Phosphate Glasses ◽  
Relationship Of ◽  
The Relationship

The electrical properties of 10M2O-36Fe2O3-54P2O5 (M=Li, Na and K) glasses were studied in the temperature range from 323 to 573 K. Non-linear Arrhenius behavior was observed for all the samples examined. It was shown that in both high- and low-temperature ranges, the replacement of Li, Na and K would result in decreases in both the dc conductivity and the activation energy. Analysis of the relationship of the parameters included in the Arrhenius equation, activation energy and the pre- exponential factor for each sample, preliminary explanations for these experimental phenomena have been presented.

Mechanical Behaviors of Torsion Actuator of Shape Memory Alloy

2008 ◽  
Vol 385-387 ◽  
pp. 213-216 ◽  
Author(s):  
Bo Zhou ◽  
Zhen Qing Wang ◽  
Sung Ho Yoon ◽  
Guang Ping Zou
Keyword(s):  
Phase Transformation ◽  
Shape Memory Alloy ◽  
Shape Memory ◽  
Mechanical Model ◽  
Solid Mechanics ◽  
Mechanical Behaviors ◽  
Thin Walled Tube ◽  
Thin Walled ◽  
Relationship Of ◽  
The Relationship

A shape memory alloy (SMA) torsion actuator is designed by using SMA wires and a thin-walled tube. A mechanical model, which predicts the thermo-mechanical behaviors of the SMA torsion actuator, is developed based on the knowledge of solid mechanics and constitutive relation of SMA. The relationship of the torsion-angle and temperature of the SMA torsion actuator is numerically described by using the mechanical model coupled with Tanaka’s, Liang’s and Zhou’s phase transformation models of SMA respectively. Results show the mechanical model well predict the thermo-mechanical behaviors of the SMA torsion actuator.

The relationship of the scleractinian corals to the rugose corals

Paleobiology ◽  
1980 ◽  
Vol 6 (02) ◽  
pp. 146-160 ◽  
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.

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

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.

Studies on Leukemogenic and Sarcomagenic Viruses

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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