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1.
Several ways to produce microporous and mesoporous carbon monoliths by template assisted synthesis routes are described. Pressed zeolite (HY) and silica powder tablets have been used as templates. Sucrose acts as a carbon precursor and as a binder between the carbon particles as well. In the case of zeolite template, the carbon porosity could be increased by additional loading of the template with ethene. Due to the balance between mechanic stability and porosity of the carbon monolith, an optimal amount of sucrose is required. The final products were characterized by low temperature nitrogen adsorption. 相似文献
2.
150~500 mm长度的各种X射线光学元件可用于光束导引,光束调整,以及单色化。本文介绍了两种不同的大型X射线反射镜。第一种为单层反射镜,这种反射镜以2°掠入射角在软X射线区(50~200 eV)起全反射镜作用,可用于自由电子激光器,如德国汉堡的FLASH。第二种是多层镜,由于它的布喇格反射特性,适于作为反射镜以0.4~1°的入射角用于硬X射线区(20~50 keV),如层析光束线的同步辐射存储环中。两种反射镜都用最新物理汽相淀积法制备,并用磁控溅射来实现X射线光学应用所需要的优良光学品质。这一淀积工艺使不同批次的镀膜稳定性良好,有利于实际反射镜在优质衬底上的最后淀积。单层镜和多层镜在它们的相关能量范围内都有很高的反射率,表面粗糙度也很低,且在整个光学波长区这些特性表现均匀。文中所叙相关研究都是借助X射线反射计量(XRR)法,透射电子显微镜(TEM)、光学轮廓仪(OP),以及原子力显微镜(AFM)完成的。 相似文献
3.
Klaus Goffart Michael Schermann Christopher Kohl Jörg Preißinger Helmut Krcmar 《International journal of human-computer interaction》2016,32(1):39-50
Gaining a better understanding of human–computer interaction in multiple-goal environments, such as driving, is critical as people increasingly use information technology to accomplish multiple tasks simultaneously. Extensive research shows that decision biases can be utilized as effective cues to guide user interaction in single-goal environments. This article is a first step toward understanding the effect of decision biases in multiple-goal environments. This study analyzed data from a field experiment during which a comparison was made between drivers’ decisions on parking lots in a single-goal environment and drivers’ decisions in a multiple-goal environment when being exposed to the default option bias. The article shows that the default option bias is effective in multiple-goal environments. The results have important implications for the design of human–computer interaction in multiple-goal environments. 相似文献
4.
In this paper we describe two projects on contextualized computer systems and audio augmented environments we are currently
working on at the Fraunhofer Institutes FIT and IMK. In this paper we will only focus on the world models and the augmentation
layer. Both projects are based on completely different technologies, and use different representation methods and interaction
facilities. While in hippie users are moving with small laptop computers or wearable computers with a small visual display,
in LISTEN users will have only a wireless headphone displaying spatially rendered sound-scenes.
Correspondence to: J. Goβmann, Fraunhofer-IMK, Schloss Birlinghoven, D-53754 St Augustin, Germany. 相似文献
5.
E. Dinslage Beckel Schwaibold F. Frhr v. Falkenhausen Mohr Griebel Rauen C. I. Kruisheer von Gierke H. Mohler I. Stahn L. Maaskant H. J. Steinbeck Brüning Pawletta W. Schreiber Kanitz Schnetka H. Ketterl Damm G. Stamm W. Ludorff Edmund Baertich H. Ketterl Ketterl Lars Erlandsen Riffart Lars Erlandsen Masling v. Noël Jesser Jahr W. Brandt Schönfeld W. Preiß K. Höll J. J. van Eck W. Wodsak Bomskov C. Pyriki Schönfeld Werner Kluge W. Hämmerle W. Bartels Flury Wrede W. Bartels 《European Food Research and Technology》1938,76(2):160-208
6.
R. Grau O. Windhausen J. Großfeld Kanitz W. Ludorff H. J. Steinbeck K. Höll Fr. Bartschat H. Mohler J. Ph. Bruno Roßmann C. Griebel H. Damm W. Schreiber H. Ketter C. I. Kruisheer W. Bartels W. Sutthoff Schnetka Brüning G. Stamm W. Wodsak L. W. Jirak Kluge Riffart W. Wodsak Jesser W. Preiß K. Müller Reichard Jahr 《European Food Research and Technology》1937,73(1):51-119
7.
Near infrared calibrations have been derived and used routinely in the measurement of fat, moisture, protein, collagen free protein and starch in meat patties. The lower standard error of prediction (SEP) values for moisture, protein, fat and starch content determination were recorded with the first derivative calibration than with those of the second derivative treatment. The prediction for the moisture and protein content determinations with first derivative transforms were satisfactory, the correlation coefficients (r) being 0.99 and 0.98, respectively. Determining the fat content with both first and second derivative data showed excellent results, r amounting to more than 0.99. The result obtained for the starch and collagen free protein (CFP) content determination with the first derivative calibration, as well as with the second derivative treatment, showed a deviation from the chemical data and r was less than 0.97 in both cases. It is recommended that a sample preparation, such as demoisturizing or defatting, is needed to get a high correspondence with reference methods for starch and hydroxyproline determination in meat patties. 相似文献
8.
9.
R. Weiβ 《Cement and Concrete Research》1979,9(4):405-416
The residual strength of damaged concrete having a structure similar to a pile of fragments is determined by the frictional resistance to slide of the elements. In the statistical-rheological model this fact is taken into consideration by connecting in parallel extended friction elements. Their load capacity can be expressed by a critical stress which is assumed to be at random in the system and can be described by a steady distribution. A criterion of stability is formulated as an unequation making it possible to compute the stress the system becomes unstable and fail s as well as the total strain at any load. Two examples - the stress-strain relation at elevated temperatures and the restriction of thermal expansion under non-steady state conditions - demonstrate efficiency and bounds of the model. 相似文献
10.
The structure of thin iron films of thickness about 1500 Å was studied by means of X-ray diffraction analysis. Evaporation and X-ray examination were carried out in the 10?10 Torr range without exposing the films to the atmosphere using a recently developed ultrahigh vacuum diffraction chamber. The films were deposited onto glass substrates at a rate of 10 Å min?1 at room temperature and were subsequently annealed at 320°C. They show a (110) fibre texture with a mean crystallite size of the (110)-oriented crystals that was distincly smaller than the film thickness. The lattice parameter was found to be always less than the corresponding value for a bulk iron standard, which can be ascribed to the formation of thermally induced strains. 相似文献