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291.
We surveyed well-acquainted dyads about two key moral character traits (Honesty–Humility, Guilt Proneness), as well as several other individual differences. We examined self-other agreement, similarity, assumed similarity, and similarity-free agreement (i.e., self-other agreement controlling for similarity and assumed similarity). Participants projected their own level of moral character onto their peers (i.e., moderately high assumed similarity), but were nonetheless able to judge moral character with reasonable accuracy (moderately high self-other agreement and similarity-free agreement), suggesting that moral character traits can be detected by well-acquainted others. Regardless of reporting method, Honesty–Humility and Guilt Proneness were correlated with delinquency, unethical decision making, and counterproductive work behavior, suggesting that unethical behavior is committed disproportionately by people with low levels of these character traits.  相似文献   
292.
The present study explores gender differences in help-seeking attitudes and the effects of counsellor gender and problem type on those attitudes among Turkish high school students. The Attitudes towards Seeking Help Scale and a survey instrument concerning related factors were administered to 342 adolescents. ANOVAs show that male and female students displayed different help-seeking attitudes. Females held much more positive help-seeking attitudes than did males. For females, neither counsellor gender, problem type nor their interaction affected help-seeking attitudes. By contrast, among males, the interaction of counsellor gender and problem type influenced total help-seeking attitudes as well as two of the subscales – psychological distress and confidence in mental health professionals. Limitations, suggestions for further research and implications are discussed.  相似文献   
293.
294.
A U(3) model proposed by Iachello for superconductivity in cuprate materials is analyzed. The model consists of s and d pairs (approximated as bosons) in a two-dimensional Fermi system with a surface. The transition occurs between a phase in which the system is a condensate of one type of boson, and a phase which is a mixture of two types of bosons. In the current work we have investigated the validity of the Bogoliubov approximation, and we used a reduced Hamiltonian to determine a phase diagram, the symmetry of the phases, and the temperature dependence of the heat capacity.  相似文献   
295.

Microstructural changes associated with the martensitic transformation from cubic (parent phase) to trigonal (R phase) which occurs with decreasing temperature in Ti50Ni48Fe2 have been intensively studied by in-situ electron microscopy. Although the parent phase shows a characteristic microstructure with small domains, which are due to lattice modulation as a precursor to the transformation, their temperature dependence is contrasted with that of domains which appear below the transformation temperature in the R phase. The observations convince us that there is an essential difference between the natures of the domains observed in each state, and also reveal the formation of peculiar antiphase-like boundaries within a needle-like variant of the R phase. We also estimate the approximate size of the R phase just after nucleation and compare this with a theoretical consideration on the size of nuclei in martensites.  相似文献   
296.
Abstract

A highly tetragonal (large c/a ratio) martensite in a Fe-4 wt% Al-1·6 wt% Mn-2 wt% Calloy, which is not aged and considered to be as ‘fresh’ as possible, has been observed by high-resolution electron microscope. From the arrangement of atom rows in the [010] structure image and the corresponding electron diffraction pattern, it is concluded that carbon atoms are clustered on the (305) plane. The unit structure of these carbon-clustered regions is similar to that of the modulated structure observed in Fe-C alloys, although a periodic layer distribution of carbon atoms is not observed.  相似文献   
297.
In this study, (Gd1? x Nd x )2(Zr1? x Ce x )2O7 (0 ≤ x ≤ 0.5) ceramics have been prepared by pressureless sintering at 1973 K to investigate the influence of Nd and Ce co-doping on their electrical conductivity. The electrical conductivity of the ceramics was investigated by impedance spectroscopy measurements from 723 to 1173 K over the frequency range of 20 Hz to 2 MHz in air. The measured values obey the Arrhenius relation. For each composition, the grain conductivity gradually increases with increasing temperature from 723 to 1173 K. At a given temperature, it gradually decreases with increasing neodymium and cerium contents from x = 0 to 0.3; thereafter, the grain conductivity exhibits a slight increase with further increasing neodymium and cerium contents up to x = 0.5.  相似文献   
298.
ABSTRACT

We present results for the structural, electronic, vibrational, and electron-phonon coupling properties of LaSn3 and CaSn3 adopting the simple cubic AuCu3-type structure obtained using the the generalised gradient approximation of the density functional theory and plane wave ab initio pseudopotential method. Our electronic results show that both materials display metallic character with several bands, which have mainly Sn 5p character, crossing the Fermi level. The calculated phonon spectrum of LaSn3 accords very well with reported experimental measurements. The weights of the peaks in the Eliashberg spectral function of both compounds are enhanced with the use of experimental lattice constant in our electron-phonon calculation, increasing the value of average electron phonon coupling parameter from 0.876 to 0.937 for LaSn3 (by 7%) and from 0.642 to 0.725 for CaSn3 (by 13%). The use of experimental lattice constant also improves the agreement between theoretical and experimental values of the superconducting temperature for both compounds.  相似文献   
299.

Single-crystal 15R-SiC boules have been successfully grown by sublimation. The Vickers hardness of a Si-terminated (0001) face has been measured in the temperature range 25-1300C. As expected, the hardness decreases with increasing temperature from about 30GPa at room temperature to about 10GPa at 1300C. The fracture toughness is estimated to be about 1.0MPam 1/2 at room temperature. Transmission electron microscopy investigation of the dislocations introduced by indentation at 900 and 1300C shows that they are activated predominantly on the basal plane. Most of them consist of a single leading partial without the corresponding trailing partial.  相似文献   
300.
High-pressure X-ray diffraction studies on gadolinium sesquioxide (Gd2O3) have been carried out up to a pressure of ~25 GPa in a diamond-anvil cell at room temperature. Gadolinium oxide, which has a cubic or bixbyite structure under ambient conditions, undergoes an irreversible structural phase at around 12 GPa. The high-pressure phase has been identified as a hexagonal La2O3-type structure. The bulk modulus and its pressure derivative of this phase have been calculated.  相似文献   
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