Suchergebnisse

Die Zahl der Legehennenfarmen stieg von 23 im Jahre 1983 auf 466 im Jahre 1991 an. Entsprechend stieg auch der Anteil der Eierproduktion im Bereich der tierischen Produktion an. Der Beitrag gibt einen Überblick über die Ausdehnung der Legehennenhaltung, über Hindernisse, die bei der lokalen Eierproduktion aufgetreten sind und Empfehlungen zur Beseitigung der Schwierigkeiten. (DÜI-Ott)

The quaternary alloy of Cu2CdSnS4 (CCSS) is one type of thin film materials that contributes to the field of photovoltaic devices manufacturing, the importance of which has not been commonly enlightened as most of the other materials. For the preparation of CCSS thin films at 350 °C on glass substrates, the chemical spray pyrolysis technique was used. The optical properties of thin films prepared under the influence of the variation of copper solution molarity (0.03, 0.05, 0.07, and 0.09 M) on the quaternary compound were examined using a UV-vis spectrophotometer. The findings of the AFM study showed the atoms on the surface that are acclimatized in the form of nanorods with an increase in the average grain size from 62.72 to 79.17 nm. The results also showed an improvement in the average surface roughness from 5.69 to 12.8 nm when copper concentration increased from 0.03 to 0.09 M. The UV-vis results showed that the optical transmittance of CCSS decreases by increasing the solution molarity of copper, with a change in the absorption edge toward the low energy side (redshift). With an increase in the wavelength between 725 and 960 nm, a low absorption coefficient was found in the infrared region, while a strong absorption coefficient in the visible range was observed with the increase in copper solution molarity. The energy gap values decreased from 1.6 to 1.47 eV when copper solution molarity increased from 0.03 to 0.09 M. By raising copper solution molarity to 0.09 M, the refractive index at the absorption edge was increased from 1.6 to 1.97, while the extinction coefficient reduced.

Introduction Research to date on social support for adolescents with visual impairments (that is, blindness or low vision) has been primarily carried out in developed countries, and very little is known about the social support systems that are available for such adolescents in developing countries such as those in the Arab world. In the present study, social support among adolescents with and without visual impairments was investigated in Jordan, which is considered a developing country. Methods Study participants included 86 adolescents with visual impairments and 73 sighted adolescents. The instrument used to collect information in this study was an Arabic version of the Multidimensional Scale of Perceived Social Support (MSPSS). Results The level of social support reported by adolescents with visual impairments was higher than that reported by sighted adolescents. In all three domains of the MSPSS (family, friends, and significant others), students with visual impairments reported receiving more social support than those without impairments. However, there was no statistically significant effect for gender. Discussion The results of the study are not consistent with findings of previous studies, all of which were conducted in Western countries. The disparities in experiences of adolescents with visual impairments in developed and developing countries may be attributed to differences in cultural values as well as to the conceptualization of support by those involved. Implications for practitioners Special education teachers need to be aware of the cultural backgrounds of their students and to develop and implement culturally appropriate programs for them.