Adaptive photo-EMF detectors based on CdTe and their solid solutions
The complex measurements of V(Ti)-doped CdTe (crystals and films) and their solid solutions were carried out. This allowed to establish the nature and energy structure of the intrinsic defects and impurity centers and to propose the micromechsnism of photo-EMF effect. The adaptive photodetectors based on these crystals and CdTe polycrystalline films were developed.
Energy structure and micromechanism of photo‐electromotive force effect in V‐doped CdTe crystals
For the first time photo‐electromotive force (photo‐EMF) measurements were carried out for CdTe crystals doped with V atoms as a result of the photogeneration of carriers from deep impurity centers to the conduction band. Tilted geometry was applied that allowed two‐dimensional monitoring of the vi‐ bration source. The CdTe:V crystals were excited by a He–Ne laser with a wavelength of 1.15 μm (ħω = 1.08 eV) and P = 2 mW. The mechanism of the appearance of the holographic current in the CdTe:V crystals taking into account real defect structure was proposed. The frequency dependence of the ac photo‐EMF (holographic) current for the CdTe:V crystals was measured. It was shown that a low cut‐off frequency for a laser intensity I = 0.2 mW/mm2 equals 6.0 kHz, which corresponds to a response time of 26 μs. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonprofit Communication and Fundraising in China: Exploring the Theory of Situational Support in an International Context
Using a survey of 586 college students from Beijing, China, this study tested the theory of situational support by exploring Chinese students’ motivations to participate in nonprofit fundraising events. This study also compared theory variables between Chinese and U.S. college students by looking at similar data from a survey previously conducted with 514 U.S. students. There were differences between the two groups regarding constraint recognition, subjective norms, attitudes toward fundraising, and other variables, perhaps because of Confucianism, collectivism, and other differences between China and the United States. The findings generate a range of theoretical and practical implications including how nonprofit practitioners in China might develop better communication and messaging strategies to segment publics, motivate potential donors, and advance future fundraising efforts.