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Crystallography Reports - A new air cooler design (“specific two-level crystallization incubator”) with a specific arrangement of laboratory vessels by levels and double-branch air... 相似文献
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Kaloper N 《Physical review letters》2005,94(18):181601
We construct exact gravitational field solutions for a relativistic particle localized on a tensional brane in brane-induced gravity. They are a generalization of gravitational shock waves in 4D de Sitter space. We provide the metrics for both the normal branch and the self-inflating branch Dvali-Gabadadze-Porrati brane worlds, and compare them to the 4D Einstein gravity solution and to the case when gravity resides only in the 5D bulk, without any brane-localized curvature terms. At short distances the wave profile looks the same as in four dimensions. The corrections appear only far from the source, where they differ from the long distance corrections in 4D de Sitter space. We also discover a new nonperturbative channel for energy emission into the bulk from the self-inflating [corrected] branch, when gravity is modified at the de Sitter radius. 相似文献
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We show that for every there exists C > 0 such that if then asymptotically almost surely the random graph contains the kth power of a Hamilton cycle. This determines the threshold for appearance of the square of a Hamilton cycle up to the logarithmic factor, improving a result of Kühn and Osthus. Moreover, our proof provides a randomized quasi‐polynomial algorithm for finding such powers of cycles. Using similar ideas, we also give a randomized quasi‐polynomial algorithm for finding a tight Hamilton cycle in the random k‐uniform hypergraph for . The proofs are based on the absorbing method and follow the strategy of Kühn and Osthus, and Allen et al. The new ingredient is a general Connecting Lemma which allows us to connect tuples of vertices using arbitrary structures at a nearly optimal value of p. Both the Connecting Lemma and its proof, which is based on Janson's inequality and a greedy embedding strategy, might be of independent interest. 相似文献
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Nemanja Trišović Nebojša Banjac Nataša Valentić Gordana Ušćumlić 《Journal of solution chemistry》2009,38(2):199-208
The absorption spectra of nine compounds structurally related to phenytoin (5,5-diphenylhydantoin) were recorded in twelve
solvents over the range of 200 to 400 nm. The effects of solvent dipolarity/polarizability and solvent/solute hydrogen bonding
interactions were analyzed by means of the linear solvation energy relationship (LSER) concept proposed by Kamlet and Taft.
The lipophilic activity of the investigated hydantoins was estimated by calculation of their log 10
P values. The calculated values of log 10
P were correlated with the ratio of the contributions of specific and non-specific solute/solvent interactions. The correlation
equations were combined with the corresponding ED50 values to generate new equations that demonstrate exact relationship between solute/solvent interactions and the structure-activity
parameters. 相似文献
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Izabela Spaleniak Simon Gross Nemanja Jovanovic Robert J. Williams Jon S. Lawrence Michael J. Ireland Michael J. Withford 《Laser \u0026amp; Photonics Reviews》2014,8(1):L1-L5
The first demonstration of narrowband spectral filtering of multimode light on a 3D integrated photonic chip using photonic lanterns and waveguide Bragg gratings is reported. The photonic lanterns with multi‐notch waveguide Bragg gratings were fabricated using the femtosecond direct‐write technique in boro‐aluminosilicate glass (Corning, Eagle 2000). Transmission dips of up to 5 dB were measured in both photonic lanterns and reference single‐mode waveguides with 10.4‐mm‐long gratings. The result demonstrates efficient and symmetrical performance of each of the gratings in the photonic lantern. Such devices will be beneficial to space‐division multiplexed communication systems as well as for units for astronomical instrumentation for suppression of the atmospheric telluric emission from OH lines. 相似文献
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A model of an air-cooled tube (“air-heat saw”) installed in a laboratory tube furnace is presented. The setup (“crystallization tests bench”) allows easy regulation and simultaneous crystallization tests of a series of different crystallization parameters in crucible columns, enabling fast studies of obtaining crystals from materials with unknown crystallization parameters. The relationships between the crystallization rate and parameters of air-cooled tube are given and numerically analyzed. This method can also be applied in crucible or chamber furnaces. 相似文献
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Gordana Ćirić-Marjanović Igor Pašti Nemanja Gavrilov Aleksandra Janošević Slavko Mentus 《Chemical Papers》2013,67(8):781-813
Polyaniline (PANI) and polypyrrole (PPY) undergo carbonisation in an inert/reduction atmosphere and vacuum, yielding different nitrogen-containing carbon materials. This contribution reviews various procedures for the carbonisation of PANI and PPY precursors, and the characteristics of obtained carbonised PANI (C-PANI) and carbonised PPY (C-PPY). Special attention is paid to the role of synthetic procedures in tailoring the formation of C-PANI and C-PPY nanostructures and nanocomposites. The review considers the importance of scanning and transmission electron microscopies, XPS, FTIR, Raman, NMR, and EPR spectroscopies, electrical conductivity and adsorption/desorption measurements, XRD, and elemental analyses in the characterisation of C-PANIs and C-PPYs. The application of C-PANI and C-PPY in various fields of modern technology is also reviewed. 相似文献