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51.
Gregor D. Wehinger 《化学,工程师,技术》2021,93(7):1049-1057
This article introduces assistant professor Gregor D. Wehinger of the Institute of Chemical and Electrochemical Process Engineering at Clausthal University of Technology. Besides recent research projects and teaching activities, he gives an overview about his commitment to the community. He reports on current research results in the field of CFD modeling of packed-bed reactors, redox-flow batteries, and multiphase systems. Furthermore, the use of virtual reality in teaching is presented. 相似文献
52.
Synthesis and Antiangiogenic Properties of Tetrafluorophthalimido and Tetrafluorobenzamido Barbituric Acids 下载免费PDF全文
Dr. Agnieszka Ambrożak Christian Steinebach Dr. Erin R. Gardner Shaunna L. Beedie Dr. Gregor Schnakenburg Dr. William D. Figg Prof. Dr. Michael Gütschow 《ChemMedChem》2016,11(23):2621-2629
The development of novel thalidomide derivatives as immunomodulatory and anti‐angiogenic agents has revived over the last two decades. Herein we report the design and synthesis of three chemotypes of barbituric acids derived from the thalidomide structure: phthalimido‐, tetrafluorophthalimido‐, and tetrafluorobenzamidobarbituric acids. The latter were obtained by a new tandem reaction, including a ring opening and a decarboxylation of the fluorine‐activated phthalamic acid intermediates. Thirty compounds of the three chemotypes were evaluated for their anti‐angiogenic properties in an ex vivo assay by measuring the decrease in microvessel outgrowth in rat aortic ring explants. Tetrafluorination of the phthalimide moiety in tetrafluorophthalimidobarbituric acids was essential, as all of the nonfluorinated counterparts lost anti‐angiogenic activity. An opening of the five‐membered ring and the accompanying increased conformational freedom, in case of the corresponding tetrafluorobenzamidobarbituric acids, was well tolerated. Their activity was retained, although their molecular structures differ in torsional flexibility and possible hydrogen‐bond networking, as revealed by comparative X‐ray crystallographic analyses. 相似文献
53.
Bjarne Kreitz Jens Friedland Robert Güttel Gregor D. Wehinger Thomas Turek 《化学,工程师,技术》2019,91(5):576-582
Investigating the effect of concentration forcing of the CO2 methanation is not only relevant for power‐to‐gas plants but also for the study of dynamic phenomena of this reaction. In this study a Ni/Al2O3 catalyst is investigated under concentration forcing at industrially relevant conditions. The dynamic experiments allow an evaluation in terms of the reaction rate and enable the study of the reaction mechanism. The experiments show that no methane is formed in the CO2‐rich part of the cycle, whereas a fast hydrogenation of carbonaceous species to methane takes place upon switching to H2. 相似文献
54.
An empirical examination of application frameworks success based on technology acceptance model 总被引:1,自引:0,他引:1
Gregor Polan?i? Author Vitae Marjan Heri?ko Author VitaeAuthor Vitae 《Journal of Systems and Software》2010,83(4):574-584
Framework-based development is currently regarded as one of the most promising software development approaches when it comes to improvements in lead time, productivity and quality. However, many frameworks and projects based on frameworks still report failures, which indicate that there are problems related to both frameworks technology and frameworks usage. The objective of our research was to examine the major drivers that have an impact on a framework’s acceptance and a framework’s success. We used the technology acceptance model (TAM) and Seddon’s information systems success model as our underlying theory. Data collected from an online survey of 389 active framework users was used to test hypothesized models. Data analysis was performed via structural equation modeling. Our findings support the post-adoption version of TAM and the relationship between continuous use and the successful use of systems, where more use also means more net benefits. We found that the successful use of frameworks is mainly dependent on two factors: continuous framework usage intention and the perceived usefulness of the framework. Several practical and theoretical implications can be foreseen including advances in framework development guidelines and insight into the relationship between the acceptance and success of frameworks. 相似文献
55.
Shin-ichiro Ohno Gregor P. C. Drummen Masahiko Kuroda 《International journal of molecular sciences》2016,17(2)
Many types of cells release phospholipid membrane vesicles thought to play key roles in cell-cell communication, antigen presentation, and the spread of infectious agents. Extracellular vesicles (EVs) carry various proteins, messenger RNAs (mRNAs), and microRNAs (miRNAs), like a “message in a bottle” to cells in remote locations. The encapsulated molecules are protected from multiple types of degradative enzymes in body fluids, making EVs ideal for delivering drugs. This review presents an overview of the potential roles of EVs as natural drugs and novel drug-delivery systems. 相似文献
56.
Michael J Zvolensky Laura E Gibson Anka A Vujanovic Kristin Gregor Amit Bernstein Christopher Kahler C W Legues Richard A Brown Matthew T Feldner 《Nicotine & tobacco research》2008,10(8):1415-1427
The present investigation examined whether daily smokers with posttraumatic stress disorder (PTSD), as compared to daily smokers with either anxiety psychopathology or no current Axis I psychopathology, have decreased success in the early phases of a self-guided smoking quit attempt. Participants were 140 daily smokers (81 women; M (age) = 29.5; SD = 11.9; range = 18-65 years); approximately one-third of the sample met criteria for current PTSD (n = 47), one-third met criteria for other current anxiety disorders (without PTSD; n = 33), and one-third did not meet criteria for any current Axis I disorder (n = 60). Consistent with prediction, membership in the PTSD group, compared to membership in the other anxiety disorders group and the group with no current Axis I psychopathology, was associated with increased risk of lapse during the first week following quit day. Additionally, daily smokers with PTSD and other anxiety disorders were at significantly increased risk of relapse during the first week post-cessation compared to persons without Axis I psychopathology. However, the PTSD group and the other anxiety disorders group did not differ from one another in terms of relapse. Results suggest that PTSD is associated with increased risk of smoking lapse and relapse compared to smokers with no current Axis I psychiatric problems, and increased risk of early smoking lapse but not relapse, as compared to those with other anxiety disorders. Findings provide novel evidence that PTSD, and perhaps anxiety disorders more generally, may be important factors in reducing the odds of successful unaided quit attempts in the early phases of cessation. 相似文献
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Gregor Schinkel Immo Garrn Benjamin Frank Ulrich Gernert Helmut Schubert Reinhard Schomcker 《Materials Chemistry and Physics》2008,111(2-3):570-577
The engineering aspects of the preparation of nanostructured alumina ceramic precursors by alcoholate hydrolysis using microemulsions as reaction media are investigated here. The precipitate was subjected to several treatment steps. Although the properties of the primary precipitated powders are independent of the chemical or reaction engineering parameters of the precipitation procedure, the structure of treated powders and sintered, dense ceramics strongly depends on thermal and mechanical handling like crystallization or grinding of the alumina ceramic precursor. Strong differences are manifested in relative densities and sintering kinetics and can be observed by SEM analysis. 相似文献
60.