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排序方式: 共有455条查询结果,搜索用时 15 毫秒
81.
The structures of two new biologically active chlorinated metabolites isolated from submerged cultures of the ascomycete Lachnum papyraceum have been elucidated by NMR and mass spectroscopy. The compounds, lachnumon (1) and lachnumol A (2), which structurally are related with mycorrhizin A that also is produced by the fungus, contain an unusual chlorinated epoxide group. 相似文献
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84.
Zhong-Xin Chen Joost van der Eyden† Wouter Koot Rob van den Berg Jan van Mechelen Anke Derking 《Journal of the American Ceramic Society》1995,78(11):2993-3001
Homogeneous thin films of zinc titanate have been successfully prepared on Si(100) wafers by depositing a film of zinc and titanium oxides (ZnO-TiO2 ) by low-pressure metalorganic chemical vapor deposition (MOCVD), followed by an annealing treatment. The precursors used for the deposition were diethylzinc (DEZ), tetraisopropoxide titanium (TPT), and water. By performing the deposition at temperatures between 140 and 350C, the stoichiometry of the as-deposited films could be effectively controlled over Zn/Ti ratios between 0.5 and 2.5, which cover the composition of various zinc titanate phases identified in the literature. The as-deposited ZnO-TiO2 films are amorphous, and possess a fairly smooth surface. XPS and SIMS analysis showed that the composition of these films is uniform over the wafer as well as through the films bulk. An annealing treatment of the as-deposited films at high temperature 相似文献
85.
Collybia nivalis, Favolaschia sp. 87129, Pterula sp. 82168 and Omphalotus olearius were cultivated on natural substrates. The antibiotic metabolites oudemansin A. strobilurins A, D, illudin S and pterulone were isolated and identified. A new antifungal metabolite, pterulone B, was described from cultures of Pterula sp. 82168 on wood. Collybia nivalis was found to be the first species of this genus to produce strobilurins and oudemansin A. As compared to rich media the cultivation on natural substrates resulted in the production of fewer metabolites. The concentrations of the antibiotics, however, were sufficient to inhibit other saprophytic fungi. 相似文献
86.
Hofmann Stefan G.; Newman Michelle G.; Ehlers Anke; Roth Walton T. 《Canadian Metallurgical Quarterly》1995,104(1):224
Individuals meeting criteria of the revised third edition of Diagnostic and Statistical Manual for Mental Disorders (American Psychiatric Association, 1987) for social phobia with a fear of speaking in front of people were subdivided into those with (n?=?16) and without (n?=?14) avoidant personality disorder (APD). These individuals and nonanxious controls (n?=?22) spoke in front of a small audience while speaking time, subjective anxiety, fearful thoughts, and electrocardiographic and respiratory measures were recorded. Controls spoke for longer than either social phobia group. Those with social phobia and APD reported more subjective anxiety and more fear cognitions than the other two groups; phobic individuals without APD showed greater heart rates in the phobic situation than either social phobics with APD or controls. The latter two groups did not differ in heart rate. These results indicate incongruent subjective and heart rate responses to the feared situation. A similar pattern of results was found when participants were divided into generalized and specific social phobia groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
87.
Intrusive reexperiencing in posttraumatic stress disorder (PTSD) has been linked to perceptual priming for trauma-related material. A prospective longitudinal study (N = 69) investigated perceptual priming for trauma-related, general threat, and neutral words in assault survivors with and without PTSD, using a new version of the word-stem completion task. Survivors with PTSD showed enhanced priming for trauma-related words. Furthermore, priming for trauma-related words measured soon after the trauma was associated with subsequent PTSD severity at 3, 6, and 9 months. The enhanced priming effect was specific to trauma-related words. Enhanced perceptual priming for traumatic material appears to be one of the cognitive processes operating in PTSD. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Hans-Georg Fill Anke Gericke Dimitris Karagiannis Robert Winter 《WIRTSCHAFTSINFORMATIK》2007,49(6):419-429
The development of models and methods is a vital element of design science in information systems research. In this paper a formal process modeling language is developed which incorporates IEB (Integrated Enterprise Balancing)/4R (Risk, Return, Regulation, Reporting) requirements formulated by Faisst and Buhl [FaBu05]. This is realized through the inclusion of 4R elements and 4R relations into the new 4R process modeling language. An evaluation of the process modeling language with regard to the assessment criterion “feasibility of implementation” was successfully executed using the meta modeling platform ADONIS. For that purpose the ADONIS modeling language for business processes (ADONIS BPMS) was extended with additional 4R modeling elements. Furthermore a new model type as well as required classes and relation classes have been developed which enable the connection of the 4R process modeling language to the research results of the above mentioned contribution. 相似文献
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90.
Fengjing Jiang Anke Kaltbeitzel Junliang Zhang Wolfgang H. Meyer 《International Journal of Hydrogen Energy》2014
Poly(4-vinyl pyridine) nano-spheres (P4VP-NS) stabilized poly(vinyl phosphonic acid) (PVPA) membranes were prepared as proton conducting membranes for fuel cells. The acid–base interactions between P4VP-NS and PVPA were utilized to improve the dimensional and thermal stability of PVPA. In this work, the effects of acid–base interactions on proton conductivity and thermal stability were quantitatively determined and discussed based on the results of 1H magic-angle-spin NMR (1H MAS NMR), Fourier transfer infrared spectroscopy (FTIR) and impedance spectroscopy measurements. 相似文献