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101.
102.
Der Wandel in Kommunikation und Informationsbeschaffung hat auch vor Schulen nicht halt gemacht. Das Lernen mit modernen Medien
ist inzwischen notwendiger Bestandteil jeder Schulausbildung geworden. Der folgende Beitrag gibt einen überblick über die
M?glichkeiten der Nutzung von Lernsoftware im Internet und zeigt die damit verbundenen datenschutzrechtlichen Probleme auf. 相似文献
103.
The halogenated boron-doped diamond (BDD) surfaces were reacted with sodium azide through a nucleophilic substitution reaction. The resulting azide-terminated BDD surfaces were used to trigger the "click" reaction. Because of the attractive electrochemical properties of ferrocene-containing molecules, such as fast electron transfer rates, reversible redox activities, and favorable redox potentials, we show that ferrocene derivatives can be grafted onto non-oxidized diamond surfaces by click"chemistry". These redox-active ferrocene-containing layers on a BDD surface, because of their ability to store and release charges reversibly, have the potential to be used as hybrid molecular/semiconductor memory devices. 相似文献
104.
105.
106.
Summary Poly (1,4-butadiene-b-4-vinylpyridine) blockcopolymers are made conductive by formation of the complex salt of the 4-VP-block with tetracyanoquinodimethane (TCNQ). Microphase separated morphologies are obtained where the conductive 4-VP phase is continous or forms a network on a submicron scale in a continous elastomer phase. While the absolute value of the conductivity of 10-3–10-4 Scm-1 depends on the morphology the activation energy typical for an electron hopping process is approximately the same as in the low molecular weight complex with ethylpyridine. 相似文献
107.
This study examined work-related outcomes of recovery during leisure time. A total of 147 employees completed a questionnaire and a daily survey over a period of 5 consecutive work days. Multilevel analyses showed that day-level recovery was positively related to day-level work engagement and day-level proactive behavior (personal initiative, pursuit of learning) during the subsequent work day. The data suggest considerable daily fluctuations in behavior and attitudes at work, with evidence that these are related to prior experience and opportunity for recovery in the nonwork domain. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Andrea Goldson Melanie Lam Christine H Scaman Sabine Clemens Allison Kermode 《Journal of the science of food and agriculture》2008,88(4):619-625
BACKGROUND: Oral therapy with phenylalanine ammonia lyase (PAL), naturally encapsulated in plant cells, may provide a potential alternative treatment for hyperphenylalaninemic patients, including those with phenylketonuria. Therefore different sources of plant tissue were investigated for PAL activity. RESULTS: Enzyme activity was highest in grain seedlings, with maximal enzyme activity in 7‐day‐old red spring wheat (Triticum aestivum L.) seedlings. The PAL activities of leaves and roots/endosperm of wheat seedlings were 11.90 ± 2.64 and 6.48 ± 1.59 µmol h?1 g?1 dry weight respectively. Three PAL‐related polypeptides with molecular weights of 74, 83 and 103 kDa were identified in wheat seedling leaf tissues, while only the 74 kDa polypeptide was detected in root/endosperm tissues. Dehydration was investigated as a method of concentrating PAL in wheat seedlings. Freeze‐drying was found to retain the most PAL activity (>90% recovery on a dry weight basis) compared with air drying and vacuum microwave drying for both leaf and root/endosperm samples. CONCLUSION: This study has led to a better understanding of PAL activity and stability in plant tissues and provides the basis for developing a natural plant preparation as a dietary supplement for the treatment of hyperphenylalaninemia. Copyright © 2007 Society of Chemical Industry 相似文献
109.
Dikkers Josje; Geurts Sabine; den Dulk Laura; Peper Bram; Kompier Michiel 《Canadian Metallurgical Quarterly》2004,11(4):323
In the present study, we examined the associations among work-home culture (WHC), the utilization of work-home arrangements (WHAs), and work-home interference (WHI) among 638 workers from a Dutch financial consultancy firm. We (a) developed a typology of WHC, (b) examined whether the utilization of 6 WHAs differed for various types of WHC, (c) determined whether various types of WHC and the utilization of WHAs were related to WHI, and (d) studied these associations for subgroups of workers. Results showed that WHCs can be characterized by 2 dimensions, i.e., support and hindrance. More supportive and less hindering WHCs were not associated with a higher utilization of WHAs, but did covary with lower levels of WHI. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
110.
Herschbach Peter; Duran Gabriele; Waadt Sabine; Zettler Angela; Amm Christoph; Marten-Mittag Birgit; Strian Friedrich 《Canadian Metallurgical Quarterly》1997,16(2):171
This study reports the psychometric properties of a 45-item diabetes-specific questionnaire, the Questionnaire on Stress in Patients with Diabetes—Revised (QSD-R), a modified and shortened version of the QSD (G. Duran et al; see record 1996-18805-001). The QSD-R was filled out by 1,930 individuals with insulin-dependent diabetes mellitus and noninsulin-dependent diabetes mellitus. Eight consistent scales were identified (values of Cronbach's α: .69–.81). The test-retest reliability for the total score after a 5-week interval was rtt?=?.63. The results provide evidence for the reliability and validity of this instrument. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献