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81.
Benedikt Scherger Steffen Wietzke Maik Scheller Nico Vieweg Matthias Wichmann Martin Koch Karin Wiesauer 《Journal of Infrared, Millimeter and Terahertz Waves》2011,32(7):943-951
We investigate different micro-powders that can be used as base materials for THz lenses fabricated by compression molding.
For this application materials with a very weak THz absorbance and low dispersion are required. By measuring the THz absorption
coefficient and refractive index of pellets pressed from the different micro-powders, we identify several materials that are
well suited for the fabrication of compression molded THz lenses (CMLs). In addition, a considerable range of the refractive
index is covered by the samples, which will allow for the fabrication of CMLs with different focal lengths for one and the
same lens design. 相似文献
82.
Soraya Abdelhaleem A. E. Hassanien Rameez Ahmad Matthias Schuster A. H. Ashour Monica Distaso Wolfgang Peukert P. J. Wellmann 《Journal of Electronic Materials》2018,47(12):7085-7092
Highly dispersive Cu2ZnSnS4 (CZTS) nanoparticles were successfully synthesized by a simple solvothermal route. A low cost, non-vacuum method was used to deposit CZTS nanoparticle ink on glass substrates by a doctor blade process followed by selenization in a tube furnace to form Cu2ZnSn (S,Se)4 (CZTSSe) layers. Different selenization conditions and particle concentrations were considered in order to improve the crystallinity and surface morphology; the annealing temperature was varied between 400°C and 550°C and the annealing time was varied between 5 min and 20 min in a selenium-nitrogen atmosphere. The influence of annealing conditions on structural, compositional, optical and electrical properties of CZTSSe thin films was studied. An improvement in the structural and surface morphology was observed with increasing of annealing temperature (up to 500°C). An enhancement in the crystallinity and surface morphology were observed for thin films annealed for 10–15 min. Absorption study revealed that the band gap energy of as-deposited CZTS thin film was approximately 1.43 eV, while for CZTSSe thin films it ranged from 1.15 eV to 1.34 eV at different annealing temperatures, and from 1.33 eV to 1.38 eV for different annealing times. 相似文献
83.
Britta Marko Paulina Heurich Patrick Thon Frieda Zimmer Lars Bergmann Hartmuth Nowak Katharina Rump Bjrn Koos Michael Adamzik Matthias Unterberg Tim Rahmel 《International journal of molecular sciences》2022,23(14)
The functionally important NF-κB1 promoter polymorphism (−94ins/delATTG) significantly shapes inflammation and impacts the outcome of sepsis. However, exploratory studies elucidating the molecular link of this genotype-dependent pattern are lacking. Accordingly, we analyzed lipopolysaccharide-stimulated peripheral blood mononuclear cells from both healthy volunteers (n = 20) and septic patients (n = 10). All individuals were genotyped for the −94ins/delATTG NF-κB1 promoter polymorphism. We found a diminished nuclear activity of the NF-κB subunit p50 in ID/DD genotypes after 48 h of lipopolysaccharide stimulation compared to II genotypes (p = 0.025). This was associated with higher TNF-α (p = 0.005) and interleukin 6 concentrations (p = 0.014) and an increased production of mitochondrial radical oxygen species in ID/DD genotypes (p = 0.001). Although ID/DD genotypes showed enhanced activation of mitochondrial biogenesis, they still had a significantly diminished cellular ATP content (p = 0.046) and lower mtDNA copy numbers (p = 0.010) compared to II genotypes. Strikingly, these findings were mirrored in peripheral blood mononuclear cells taken from septic patients. Our results emphasize the crucial aspect of considering NF-κB subunits in sepsis. We showed here that the deletion allele of the NF-κB1 (−94ins/delATTG) polymorphism was associated with the lower nuclear activity of subunit p50, which, in turn, was associated with aggravated inflammation and mitochondrial dysfunction. 相似文献
84.
Matthias Rass Martin Dumbach Frank Danzinger Angelika C. Bullinger Kathrin M. Moeslein 《Creativity & Innovation Management》2013,22(2):177-194
This article examines the role of social relations and networks in open innovation settings. Building on extant open innovation literature as well as on social capital theory, we develop a model that conceptualizes social capital as a mediator between the implementation of open innovation instruments and firm performance. In doing so, this paper adds to the understanding of the role of structure and content of social relations in open innovation contexts as well as of sustainable side‐effects of open innovation. In particular, we argue that apart from a direct effect of open innovation instruments on firm performance, there is also a mediated relationship between these variables. More precisely, we propose that the implementation of open innovation instruments strengthens an organization's social capital, which is, in turn, positively related to firm performance. 相似文献
85.
Daniel Schreckling Johannes Köstler Matthias Schaff 《Information Security Technical Report》2013,17(3):71-80
We introduce Kynoid, a real-time monitoring and enforcement framework for Android. Kynoid is based on user-defined security policies which are defined for data-items. This allows users to define temporal, spatial, and destination constraints which have to hold for single items. We introduce an innovative approach to allow for the real-time tracking and enforcement of such policies. In this way, Kynoid is the first extension for Android which enables the enforcement of security policies of data-items stored in shared resources. We outline Kynoid's architecture, present its operation and discuss it in terms of applicability, and performance. By providing a proof-of-concept implementation we further show the feasibility of our framework. 相似文献
86.
87.
Horst Brodowsky Matthias Albus Qiyuan Chen Zhongliang Xiao Zhoulan Yin 《Journal of Electronic Materials》2011,40(5):907-914
The thermoelectric power of Rh and Ir was redetermined between 100 K and 1400 K. It varies almost linearly from +1.7 μV K−1 to −3.8 μV K−1 for Rh and from +1.5 μV K−1 to −2.2 μV K−1 for Ir. The diffusive part of the thermopower could be calculated from the density of states. It is approximately equal to the temperature dependence of the electrochemical potential of the electrons divided by the electronic charge. This is attributed to the approximate establishment of local equilibrium between electrons and lattice atoms above 400 K—a condition not fulfilled in the phonon-drag regime below 300 K. 相似文献
88.
Reconfigurable handling system 总被引:1,自引:0,他引:1
Rainer M��ller Martin Esser Markus Jan?en Matthias Vette Burkhard Corves Mathias H��sing Martin Riedel 《Production Engineering》2011,5(4):453-461
The demand for more versatile assembly and handling systems to facilitate customized production is gaining in importance, especially with regard to the constantly-increasing cost pressure, to expansion of the range of product versions and the shortening of innovation cycles. As a cost-effective approach for frequently changing assembly tasks, a novel manipulation concept has been developed by combining given robot technologies. This new handling system has a modular and adaptable layout, which consists of several mobile arms to manipulate the object in six-dimensional Cartesian space. After grasping, when the arms are attached to the object, the mechanical architecture is similar to parallel manipulators or cooperating robots. As the mounting and gripping points of the arms can easily be changed, the manipulator can be reconfigured so as to match the user’s preferences and needs. In addition to the kinematic adaption the regarding task, the hardware and new functions can be reconfigured as well. Contact elements, measurement and assembly devices as well as testing modules can easily be in integrated in the concept. A modular automatic control concept combined with a self-optimizing planning tool helps the user to find the optimal configuration and realize it in an economic way. 相似文献
89.
Stefan Linsinger Matthias Eul Christian Schwickert Rodolphe Decourt Bernard Chevalier Ute Ch. Rodewald Jean-Louis Bobet Rainer Pöttgen 《Intermetallics》2011,19(10):1579-1585
New ordered Laves phases RENi4Mg (RE = Sc, Sm, Tb–Lu) were synthesized from the elements in sealed tantalum ampoules in an induction furnace. Six of the structures were refined on the basis of X-ray single crystal data. The diffraction experiments gave hint for small homogeneity ranges RE1+xNi4Mg1?x. Magnetic susceptibility measurements show Curie–Weiss behavior for RE = Gd, Dy, Ho, Tm, Yb and the resulting effective magnetic moments suggest both stable trivalent states for all RE and a non-magnetic state for Ni. Gd1+xNi4Mg1?x (x ≈ 0.12) orders antiferromagnetically at a Néel temperature of TN = 4.6(5) K. Resistivity measurements reflect the metallic nature of these compounds. 相似文献
90.
Berking Matthias; Margraf Matthias; Ebert David; Wupperman Peggilee; Hofmann Stefan G.; Junghanns Klaus 《Canadian Metallurgical Quarterly》2011,79(3):307
Objective: As emotion regulation is widely considered to be a primary motive in the misuse of alcohol, our aim in the study was to investigate whether deficits in adaptive emotion-regulation skills maintain alcohol dependence (AD). Method: A prospective study investigated whether emotion-regulation skills were associated with AD and whether these skills predicted alcohol use during and after treatment for AD. Participants were 116 individuals treated for AD with cognitive–behavioral therapy. Emotion regulation and severity of AD symptoms were assessed by self-report. Alcohol use during treatment was assessed by Breathalyzer and urine analysis for ethyl glucuronide; alcohol use during the 3-month follow-up interval was assessed by self-report. Results: Pretreatment emotion-regulation skills predicted alcohol use during treatment, and posttreatment emotion-regulation skills predicted alcohol use at follow-up, even when controlling for other predictors potentially related to emotion regulation. Among a broad range of specific emotion-regulation skills, the ability to tolerate negative emotions was the only skill that negatively predicted subsequent alcohol consumption when controlling for the other skills. Individuals in the AD sample reported significantly larger deficits in emotion-regulation skills than did those in a nonclinical control sample but significantly less than did those in a sample of individuals exclusively meeting criteria for major depressive disorder. Conclusions: Enhancement of general emotion-regulation skills, especially the ability to tolerate negative emotions, appears to be an important target in the treatment of AD. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献