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121.
Structural Chemistry - 相似文献
122.
Structural Chemistry - Sydney Brenner was among those who created the modern science of molecular genetics. He was primarily an experimentalist yet his philosophical views on science will also have... 相似文献
123.
Structural Chemistry - Nadrian (Ned) Seeman (1945-2021) was a crystallographer turned nanoscientist who pioneered a new direction of research at the borderline of the two fields. He constructed new... 相似文献
124.
Structural Chemistry - On April 8, 1982, Dan Shechtman conducted an electron diffraction experiment on an aluminum/manganese alloy. The diffraction pattern showed tenfold symmetry although the... 相似文献
125.
Satya P. Jammy Gihan R. Mudalige Istvan Z. Reguly Neil D. Sandham Mike Giles 《International Journal of Computational Fluid Dynamics》2016,30(6):450-454
abstractIn this paper, we report the development and validation of a compressible solver with shock capturing, using a domain-specific high-level abstraction framework, OPS, that is being developed at the University of Oxford. OPS uses an active library approach for block-structured meshes, capable of generating codes for a variety of parallel implementations with different parallelisation strategies. Performance results on various architectures are reported for the 1D Shu–Osher test case. 相似文献
126.
Ashok Kumar Malik Agnes Fekete Istvan Gebefuegi Michael Rothballer Philippe Schmitt-Kopplin 《Mikrochimica acta》2009,166(1-2):101-107
N-acylated homoserine lactones (AHLs) are produced by Gram-negative bacteria as communication signals and are frequently studied as mediators of the “quorum sensing” response of bacterial communities. AHLs are optically active components and the L-form is known to have activity in the quorum sensing. However, the knowledge regarding the stereospecific production of the AHLs in bacterial cultures is limited; therefore, there is a need for a fast and easy method for their chiral analysis. A method was developed for the preconcentration of the AHLs using single drop microextraction or liquid-liquid microphase extraction in toluene for their analysis using GC-MS. The performance of the method were determined and discussed for the chiral separation of these autoinducers using a capillary column coated with heptakis-(2,3-di-O-acetyl-6-O-t-butyldimethyl-silyl)-β-cyclodextrin. The salient feature of this study is the demonstration, that Burkholderia cepacia LA3 produced D-decanoyl-homoserine lactone beside L-decanoyl- and L-octaonyl- enantiomers. 相似文献
127.
By a well known result of Philipp (1975), the discrepancy D
N
(ω) of the sequence (n
k
ω)
k≥1 mod 1 satisfies the law of the iterated logarithm under the Hadamard gap condition n
k + 1/n
k
≥ q > 1 (k = 1, 2, …). Recently Berkes, Philipp and Tichy (2006) showed that this result remains valid, under Diophantine conditions
on (n
k
), for subexpenentially growing (n
k
), but in general the behavior of (n
k
ω) becomes very complicated in the subexponential case. Using a different norming factor depending on the density properties
of the sequence (n
k
), in this paper we prove a law of the iterated logarithm for the discrepancy D
N
(ω) for subexponentially growing (n
k
) without number theoretic assumptions.
C. Aistleitner, Research supported by FWF grant S9603-N13.
I. Berkes, Research supported by FWF grant S9603-N13 and OTKA grants K 61052 and K 67961.
Authors’ addresses: C. Aistleitner, Institute of Mathematics A, Graz University of Technology, Steyrergasse 30, 8010 Graz,
Austria; I. Berkes, Institute of Statistics, Graz University of Technology, Steyrergasse 17/IV, 8010 Graz, Austria 相似文献
128.
Sven?ScharnowskiEmail author Istvan?Bolgar Christian?J.?K?hler 《Flow, Turbulence and Combustion》2017,98(4):947-967
A transonic backward-facing step flow, at a free stream Mach number of 0.8 and a Reynolds number of 1.86 × 105 with respect to the step height, was investigated experimentally by means of planar and stereo Particle Image Velocimetry (PIV) measurements for multiple fields of view. The primary aim of this analysis is to examine whether the large temporal variations of the reattachment location is associated with the presence of large scale coherent flow structures. The mean flow reattaches ≈6.1±0.2 times the step height downstream of the step. This value fluctuates temporally as much as ±3 step heights. Measurements of the wake flow in horizontal planes show that the strong variations of the reattachment length are associated with spanwise variations of the streamwise velocity. Two-point correlations revealed large–scale coherent regions with a length of up to 7 step heights and a dominant spanwise wave-length of 1.5…2.5 step heights. Furthermore, close to the step large structures are found, which span more than 5 step heights in spanwise direction. The Reynolds stress distribution of the separated region strongly suggests that the initial streamwise momentum is transferred to the vertical component as well as to the spanwise component in comparable portions by the deformation of the initial Kelvin-Helmholtz vortices and the generation of secondary ones. As a result, the separated shear layer is characterized by eddies of various sizes and orientations. The mean flow field only shows the primary separation bubble and a secondary recirculation region. No stationary streamwise vortices could be found for the tested Reynolds number. 相似文献
129.
Sandor I. Nagy Istvan Kiss Brian Beagley Pekka Pyykkö 《Structural chemistry》1991,2(3-4):(263)471-(266)474
130.
Petrov AN Mosyagin NS Isaev TA Titov AV Ezhov VF Eliav E Kaldor U 《Physical review letters》2002,88(7):073001
A method and codes for two-step correlation calculations of heavy-atom molecules have been developed, employing the generalized relativistic effective core potential (GRECP) and relativistic coupled cluster (RCC) methods at the first step, followed by nonvariational one-center restoration of proper four-component spinors in the heavy cores. Electron correlation is included for the first time in an ab initio calculation of the interaction of the permanent P,T-odd proton electric dipole moments with the internal electromagnetic field in a molecule. Inclusion of electron correlation by GRECP/RCC has a major effect on the P,T-odd parameters of 205TlF, decreasing M by 17% and X by 22%. 相似文献