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71.
Measurements of the skylight polarized radiance distribution were performed at different measurement sites, atmospheric conditions, and three wavelengths with our newly developed Polarization Radiance Distribution Camera System (RADS-IIP), an analyzer-type Stokes polarimeter. Three Stokes parameters of skylight (I, Q, U), the degree of polarization, and the plane of polarization are presented in image format. The Arago point and neutral lines have been observed with RADS-IIP. Qualitatively, the dependence of the intensity and polarization data on wavelength, solar zenith angle, and surface albedo is in agreement with the results from computations based on a plane-parallel Rayleigh atmospheric model. 相似文献
72.
Skin smoothing effects of Dead Sea minerals: comparative profilometric evaluation of skin surface 总被引:2,自引:0,他引:2
The skin smoothing effects of three different liquid gels were compared on 20 mature women. Treatment applications were performed twice a day over a period of 4 weeks, and the skin roughness parameter (Rz) of all test participants was determined at the beginning and at the end of the study using a computer-aided laser profilometry, in accordance with DIN 4768 ff. At the end of the application period, the liquid gel with 1% of a Dead Sea mineral solution had an average skin roughness parameter reduction of 40.7%. The liquid gel without mineral additives showed an average reduction in skin roughness of 27.8%. The control gel without anti-wrinkle agents or the additives showed an average reduction of only 10.4%. 相似文献
73.
74.
Insung Park Michael Voss Brian Armstrong Rudolf Eigenmann 《International journal of parallel programming》1998,26(5):541-561
This paper contributes to the solution of several open problems with parallel programming tools and their integration with performance evaluation environments. First, we propose interactive compilation scenarios instead of the usual black-box-oriented use of compiler tools. In such scenarios, information gathered by the compiler and the compiler's reasoning are presented to the user in meaningful ways and on-demand. Second, a tight integration of compilation and performance analysis tools is advocated. M any of the existing, advanced instruments for gathering performance results are being used in the presented environment and their results are combined in integrated views with compiler information and data from other tools. Initial instruments that assist users in data mining this information are presented and the need for much stronger facilities is explained. The URSA Family provides two tools addressing these issues. URSA MINOR supports a group of users at a specific site, such as a research or development project. URSA MAJOR complements this tool by making available the gathered results to the user community at large via the World-wide Web. This paper presents objectives, functionality, experience, and next development steps of the URSA tool family. Two case studies are presented that illustrate the use of the tools for developing and studying parallel applications and for evaluating parallelizing compilers. 相似文献
75.
76.
Self-assembled quantum dots are grown on wetting layers and frequently in an array-like assembly of many similar but not exactly equal dots. Nevertheless, most simulations disregard these structural conditions and restrict themselves to simulating a pure single quantum dot. For reasons of numerical efficiency we advocate the effective one-band Hamiltonian with energy-?and position-dependent effective mass approximation and a finite height hard-wall 3D confinement potential for computation of the energy levels of the electrons in the conduction band. Within this model we investigate the geometrical effects mentioned above on the electronic structure of a pyramidal InAs quantum dot embedded in a GaAs matrix. We find that the presence of a wetting layer may affect the electronic structure noticeably. Furthermore, we establish that, in spite of the large bandgap of the InAs/GaAs heterostructure, if the dots in a vertically aligned array are sufficiently close stacked there is considerable interaction between their eigenfunctions. Moreover, the eigenfunctions of such an array are quite sensitive to certain structural perturbations. 相似文献
77.
Arnett Peter A.; Higginson Christopher I.; Voss William D.; Wright Bruce; Bender William I.; Wurst John M.; Tippin Jon M. 《Canadian Metallurgical Quarterly》1999,13(3):434
Because it is theorized that depression results in reduced available attentional capacity that, in turn, can explain the impaired performance on capacity-demanding tasks in depressed individuals, the authors predicted that multiple sclerosis (MS) patients with depressed mood would have difficulty with these types of tasks. Twenty depressed mood MS participants were compared with 41 nondepressed mood MS participants and 8 nondepressed mood controls on 5 attentional capacity-demanding clinical memory and attentional tasks and 3 tasks with minimal capacity demands. Depressed mood MS patients performed significantly worse than both nondepressed mood groups on the 3 speeded capacity-demanding attentional measures but not on any of the tasks requiring few capacity demands, supporting the authors' predictions. The possibility that the impaired performance of depressed mood MS patients on speeded attentional tasks was mediated by reduced verbal working memory capacity, impaired deployment of executive strategies that access working memory capacity, or psychomotor slowing is explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
Recently, Chlorindazone DS 1 has become an important analytical reagent for the detection of gunshot residues from newly introduced ammunition. A simplified synthesis of the precursor of the azo dye 1 , 3‐amino‐6‐chloroindazole ( 2 ), from commercially available 2,4‐dichlorobenzonitrile ( 3a ) has been described. The physical and spectroscopical properties of the known compounds 1 and 2 have been completed. 2‐Chloro‐4‐hydrazinobenzonitrile ( 4a ), 2‐bromo‐4‐hydrazinobenzonitrile (4b) and a new azo dye, 1‐(3′‐chloro‐4′‐cyanobenzene‐1′‐ylazo)‐2‐hydroxynaphthalene‐3,6‐disulfonic acid, disodium salt ( 5 ), have been investigated. 相似文献
79.
The cathodic reduction of dibenzofuran ( 2 ), 2-chlorodibenzofuran ( 4 ), and 3-chlorodibenzofuran ( 1 ) in deuterated methanol is investigated. The Birch-type reduction product 1,4-dibenzofuran ( 3 ) is formed from 1 via 2 , whereas 2-chloro-1,4-dihydrodibenzofuran ( 5 ) is obtained as by-product besides 3 from 4 as starting compound. Deuterium is only incorporated into the reduction products if CH3OD or CD3OD but not if CD3OH are used. This observation is strongly indicative of a polar mechanism involving protonation rather than a radical mechanism with hydrogen atom abstraction to be operative. 相似文献
80.
Gerhard Voss 《真空研究与实践》2002,14(4):228-233
Graphs of “high‐vacuum pressure as a function of backing pressure” (“pHV versus pVV”) and “compression as a function of backing pressure” (“K versus pVV”) are presented in this article. The performance of any turbomolecular pump can be fully and reliably evaluated with the aid of these graphs. Until now these graphs have only seldom been shown in catalogs. The catalogs generally lack the so‐called “limit lines” (“Q as a function of pVV, Kmax”). For a prescribed gas throughput Q, the limit line indicates what minimum pressure must be generated by the backing pump at the fore‐line port of the turbomolecular pump so that a stable pressure exists at the high‐vacuum side of the turbomolecular pump. Using the gas‐type‐specific limit line and the corresponding, usually well‐documented pumping‐speed curve, one can already describe the functional proficiency and performance of a selected combination of turbomolecular pump plus backing pump in an approximate manner – but not yet completely. In this article we also indicate analytical functions which excellently describe the pressure dependence of the compression and pumping speed. 相似文献