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81.
T. Bak J. Nowotny C. C. Sorrell M. F. Zhou E. R. Vance 《Journal of Materials Science: Materials in Electronics》2004,15(10):645-650
The present work describes the method of the measurement of thermoelectric power of oxide materials under the gas phase of controlled oxygen activity with high accuracy. The present study reports the thermopower data for undoped CaTiO3 at elevated temperatures (973–1323 K) and under the oxygen partial pressure in the range 10–105 Pa. The obtained experimental data indicate lack of consistency between the thermopower data determined in this work and the electrical conductivity data reported before with respect to the n–p transition point, that is, the p(O2) corresponding to the minimum of electrical conductivity differs from that at which S=0. The thermopower data were used to establish the temperature dependence of the electrical conductivity at constant thermopower. The obtained activation energy is in the range 119 kJ/mol in the n- and n–p transition regimes and assumes 146 kJ/mol in the p-type regime. 相似文献
82.
Andrzej Neimitz 《Engineering Fracture Mechanics》2004,71(11):1585-1600
In the paper the classical Dugdale model has been generalized taking into account the influence of the specimen thickness, in-plane constraint as well as the effect of the strain hardening on the level of stress distribution within the strip yield zone (SYZ). Modification has been performed utilizing Huber, Mises, Hencky as well as Tresca yield hypotheses and Guo Wanlin Tz coefficient. Results are presented in a form useful for applications. As an example, the modified model has been applied to draw the failure assessment diagram (FAD). New FAD’s have been compared with others adopted from the SINTAP procedures. 相似文献
83.
In this paper, we investigate formulation of non-local memory effect hysteretic loops in presliding domain of friction by examining the dynamic responses of a single-degree-of-freedom friction oscillator. We modify the Maxwell slip model introducing characteristic features of asperities and perform detailed examination of the system from two perspectives. The first one, termed by us as microscale, presents contribution of each individual asperity to the total friction force, whereas the second one, termed by us as macroscale, concerns friction force behaviour of the whole model treated as the unity, with a special emphasis on non-local memory effect hysteretic loops formulation, complemented by time responses. 相似文献
84.
An advanced x-ray imaging crystal spectrometer (XICS) for KSTAR tokamak has been developed by utilizing a segmented two dimensional (2D) position-sensitive multiwire proportional counter. The XICS for the KSTAR tokamak provides time-resolved measurements of the radial ion and electron temperature profiles, toroidal plasma rotation velocity, and ionization equilibrium. The segmented 2D detector with delay-line readout and supporting electronics has been adopted to improve the photon count rate capability. The current fabrication status of the XICS for the KSTAR tokamak and the first performance test results of the prototype segmented 2D detector are presented. 相似文献
85.
86.
Housing preweaned dairy calves in pairs rather than individually has been found to positively affect behavioral responses in novel social and environmental situations, but concerns have been raised that close contact among very young animals may impair their health. In previous studies, the level of social contact permitted in individual housing has been auditory, visual, or physical contact. It is unclear how these various levels of social contact compare with each other and to pair housing, when their effects on behavior and health are considered, and whether the timing of pair housing has an effect. To investigate this, 110 Holstein calves (50 males, 60 females) in 11 blocks were paired according to birth date. Within 60 h of birth, each pair of calves was allocated to 1 of 5 treatments: individual housing with auditory contact (I), individual housing with auditory and visual contact (V), individual housing with auditory, visual, and tactile contact (T), pair housing (P), or individual housing with auditory and visual contact the first 2 wk followed by pair housing (VP). At 6 wk of age, calves were subjected to a social test and a novel environment test. In the social test, all pair-housed calves (P and VP) had a shorter latency to sniff an unfamiliar calf than did individually housed calves (I, V, and T), whereas calves with physical contact (T, P, and VP) sniffed the unfamiliar calf for longer than calves on the remaining treatments (I and V). In the novel environment test, calves with physical contact (T, P, and VP) had a lower heart rate, and more of these calves vocalized during the test compared with calves without physical contact (I and V). No effect of treatment was found for clinical scores, levels of the 5 most common pathogens in feces, or in development of serum antibodies against the 3 most common respiratory pathogens. Calves housed individually are more fearful of unfamiliar calves than are pair-housed calves. Contrary to common belief, the allowance of physical contact and pair housing had no effects on the health of the calves. 相似文献
87.
A. V. Akimov V. E. Akimov P. A. Bak V. D. Bochkov L. T. Vekhoreva A. A. Korepanov P. V. Logachev A. N. Panov D. A. Starostenko O. V. Shilin 《Instruments and Experimental Techniques》2012,55(2):218-224
A pulse power system of the induction electron accelerator intended for parameters of 2 MeV, 2 kA, and operating in the double-pulse
mode is presented. The schematic diagram and main elements of the pulse system are described, and the main technical solutions
intended to produce a set of pulses with 21-kV peak voltages, peak currents of up to 8 kA, and 200-ns durations across a resistive-inductive
load are indicated. The experimental data, which were obtained when separate units and the whole power system operated on
the rated duty, are given. 相似文献
88.
Urszula Krupa-Kozak Natalia Drabińska Cristina M. Rosell Costantino Fadda Andrzej Anders Tomasz Jeliński Anita Ostaszyk 《International Journal of Food Science & Technology》2019,54(4):1121-1129
Broccoli by-products, in particular leaves, are rich sources of nutritional and bioactive components thus could constitute a valuable food additive. Although an upsurge in quantity of gluten-free products is observed further studies are required on improvement of their nutritional quality and palatability. This study aimed to investigate the influence of broccoli leaf powder (BLP) on dough behaviour, and technological characteristics and sensory quality of gluten-free mini sponge cake (GFS). Broccoli leaf powder replaced an equivalent amount (2.5%, 5%, 7.5%; w/w) of corn and potato starches in GFS formulation. Applied BLP increased the instrumental firmness of GFS but sensorial attributes (elasticity, crustiness, mastication and adhesiveness) were similar to the control. All broccoli GFS were vividly green, had small size pores properly distributed. Among them, sample with 2.5% BLP was distinguished for its desirable sensory quality, despite a slightly perceived cabbage aroma and taste. Moderate amount of BLP allows to preserve a good quality GFS improving its attractiveness and palatability. 相似文献
89.
90.
A practical computing algorithm has been developed for calculating the reflection high-energy electron diffraction (RHEED) from the molecular beam epitaxy growing surface. The calculations are based on the use of the dynamical diffraction theory in which the electrons are taken to be diffracted by a potential, which is periodic in the dimension perpendicular to the surface. The computer program presented in this paper enables calculations for three basic types of diffuse potential for crystalline heteroepitaxial structures, including the possible existence of various diffuse scattering models through the layer parallel to the surface. 相似文献