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Vanadiummetall     
Ohne Zusammenfassung  相似文献   
45.
A particular interpretation of Mach's Principle led us to ask if it was possible to have a globally inertial universe that was irreducibly associated with a non-trivial global matter distribution, Roscoe [1]. This question received a positive answer, subject to the condition that the global matter distribution is necessarily fractal, D = 2. The present paper shows how gravitational processes can arise in this universe. We begin by showing how classical Newtonian gravitation arises from point-source perturbations of this D = 2 inertial background. We then use the insights gained from this initial analysis to arrive at a general theory for arbitrary material distributions. We illustrate the process by using it to model an idealized spiral galaxy. One particular subclass of solutions, (the logarithmic spiral) has already been extensively tested (Roscoe [2, 3]), and shown to resolve large samples of optical rotation curve data to a very high statistical precision. These analyses also led to the discovery of a major new phenomenology in spiral discs—that of discrete dynamical classes, [3]. In this paper, we analyse the theory more comprehensively, showing how this phenomenology has a possible explanation in terms of an algebraic consistency condition which must necessarily be satisfied.Of equal significance, we apply the theory with complete success to the detailed modelling of eight Low Surface Brightness spirals (LSBs) which, hitherto, have been successfully modelled only by the MOND algorithm (Milgrom [5–7]. We are able to conclude that the essence of the MOND algorithm must be contained within the presented theory.  相似文献   
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Recent developments in scanning holographic microscopy that offer the prospects of new quantitative tools and imaging modalities in bio, micro, and nano sciences are reviewed. The versatility of the method is emphasized. Scanning holography can operate in an incoherent mode for fluorescence imaging, in a coherent mode for quantitative phase imaging, or in a tomographic mode for axial sectioning and rejection of the out-of-focus haze. Possible applications are illustrated with examples, and future prospects ...  相似文献   
48.
The rate constant for the reaction of O(3P) with H2O2 was measured as a function of temperature and the [H2O2]0/[O]0 ratio. The numerical solution of the appropriate rate equations was used to arrive at a mechanism which adequately describes our results and the rather divergent data in the literature. A recommended expression for the temperature dependence of the absolute rate constant is presented from consideration of the available experimental data.  相似文献   
49.
The photolysis of azomethane in the near UV has been studied at room temperature and pressures from 10 mtorr to 10 torr. The main products, C2H6 and N2, accounted for more than 99% of the reaction. Minor hydrocarbon products observed were (with quantum yields) C3H8 (3.5 × 10?3), C2H4 (3.2 × 10?4), CH4 (3 × 10?3), and n-C4H10 (trace). Quantum yields of H2 of 4 × 10?5 and 2 × 10?5 were measured at azomethane pressures of 0.1 and 1.0 torr, respectively. The minor hydrocarbon products can be accounted for by reactions of CH3 and C2H5 radicals following hydrogen abstraction from azomethane by CH3. The H2 product observed represents an upper limit for the H2 elimination from vibrationally excited C2H6 formed by CH3 combination in the system, corresponding to a rate of elimination ca. 5 × 10?5 times the competing rate of dissociation to 2CH3. Assuming a frequency factor of 1013 s?1 for the H2 elimination, a lower limit of about 90 kcal mol?1 was estimated for the energy barrier.  相似文献   
50.
Let F= {C1,C2,...,C} be a family of ndisjoint convex bodies in the plane. We say that a set Vof exterior light sources illuminates F, if for every boundary point of any member of Fthere is a point in Vsuch that is visible from ,i.e. the open line segment joining and is disjoint from F. An illumination system Vis called primitive if no proper subset of Villuminates F. Let pmax(F) denote the maximum number of points forming a primitive illumination system for F, and letpmax(n) denote the minimum of F) taken over all families Fconsisting of ndisjoint convex bodies in the plane. The aim of this paper is to investigate the quantities pmax(F) and pmax(n).  相似文献   
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