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41.
L. Olsen 《Indagationes Mathematicae》2004,15(4):535-547
We give a systematic and detailed account of the Hausdorff dimensions of sets of d-tuples of numbers defined in terms of the asymptotic behaviour of the frequencies of strings of digits in their N-adic expansion. 相似文献
42.
Sayaka Wada Kazuhiko Fujiwara Hideaki Monjushiro Hitoshi Watarai 《Analytical sciences》2004,20(11):1489-1491
The direct measurement of the circular dichroism (CD) spectra of liquid/liquid interface has been achieved for the first time by the centrifugal liquid membrane (CLM) method combined with a conventional CD spectropolarimetry. In the sample chamber of the CD spectropolarimeter, a cylindrical glass cell containing small amounts of organic and aqueous phases was rotated at ca. 7000 rpm to generate a two-phase liquid membrane with a high specific interfacial area. The CD spectra of the J-aggregate of protonated 5,10,15,20-tetraphenylporphyrin formed at the toluene/sulfuric acid interface in the rotating cell have been measured. The results demonstrated the novelty and advantages of this method. 相似文献
43.
Kyoko TakahashiKenichiro Hashimoto Ayako FujiyamaJunko Yamada Noriko KobayashiMasuo Morisaki Sayaka NakanoNoriyuki Hara Yoshinori Fujimoto 《Tetrahedron letters》2003,44(2):341-344
Feeding of the chemically prepared [24-13C, 24-2H]desmosterol to cell-free systems derived from rat liver and silkworm gut and to cultured cells of Oryza sativa followed by deuterium-decoupled 1H, 13C shift correlation NMR analysis of the biosynthesized cholesterol revealed the stereospecific incorporation of hydrogen atoms from the re-face of the C-24 position of desmosterol. 相似文献
44.
The computational Grid is currently gaining in popularity, and it enables computers scattered all over the world to be connected
by the Internet as if they are part of a large computational infrastructure. While the computational Grid gathers more and
more computational resources and the number of the applications for the computational Grid is increasing, load balancing for
the computational Grid is still not effective enough. Because the computers are connected by a wide area network on the computational
Grid, the significant communication latency and the frequency of large wave throughputs make it difficult to achieve effective
load balancing. Thus, in this paper, we propose an algorithm to predict networking loads on the computational Grid to make
the use of computational resources more efficient. The proposed algorithm based on the Markov model is evaluated using an
actual networking load. As a result, the Markov model based algorithm offers the most accurate predictions compared with the
related work.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
45.
Tage Christensen Bo Jakobsen Jon Papini Tina Hecksher Jeppe C. Dyre Niels Boye Olsen 《Journal of Non》2011,357(2):346-350
In order to describe relaxation the thermodynamic coefficient can be generalized into a complex frequency-dependent cross response function. We explore theoretically the possibility of measuring for a supercooled liquid near the glass transition. This is done by placing a thermistor in the middle of the liquid which itself is contained in a spherical piezoelectric shell. The piezoelectric voltage response to a thermal power generated in the thermistor is found to be proportional to but factors pertaining to heat diffusion and adiabatic compressibility κS(ω) do also intervene. We estimate a measurable piezoelectric voltage of 1 mV to be generated at 1 Hz for a heating power of 0.3 mW. Together with κS(ω) and the longitudinal specific heat cl(ω) which may also be found in the same setup a complete triple of thermoviscoelastic response functions may be determined when supplemented with shear modulus data. 相似文献
46.
47.
Cover Picture: On The Potential of Dynamic Nuclear Polarization Enhanced Diamonds in Solid‐State and Dissolution 13C NMR Spectroscopy (ChemPhysChem 17/2016) 下载免费PDF全文
48.
Johan P. Olsen Bryon S. Donohoe Kim Borch Peter Westh Michael G. Resch 《Cellulose (London, England)》2016,23(4):2349-2361
It is well documented that the enzymatic hydrolysis of cellulose follows a reaction pattern where an initial phase of relatively high activity is followed by a gradual slow-down over the entire course of the reaction. This phenomenon is not readily explained by conventional factors like substrate depletion, product inhibition or enzyme instability. It has been suggested that the underlying reason for the loss of enzyme activity is connected to the heterogeneous structure of cellulose, but so far attempts to establish quantitative measures of such a correlation remain speculative. Here, we have carried out an extensive microscopy study of Avicel particles during extended hydrolysis with Hypocrea jecorina cellobiohydrolase 1 (CBH1) and endoglucanase 1 and 3 (EG1 and EG3) alone and in mixtures. We have used differential interference contrast microscopy and transmission electron microscopy to observe and quantify structural features at μm and nm resolution, respectively. We implemented a semi-automatic image analysis protocol, which allowed us to analyze almost 3000 individual micrographs comprising a total of more than 300,000 particles. From this analysis we estimated the temporal development of the accessible surface area throughout the reaction. We found that the number of particles and their size as well as the surface roughness contributed to surface area, and that within the investigated degree of conversion (<30 %) this measure correlated linearly with the rate of reaction. Based on this observation we argue that cellulose structure, specifically surface area and roughness, plays a major role in the ubiquitous rate loss observed for cellulases. 相似文献
49.
Two high temperature beryllium allotropes have been stabilized at room temperature through the addition of transition elements. Superconductivity has been observed in almost all of them. Beryllium films reported superconducting in the past appear in all probability to require the presence of transition element impurities, in order to show the phenomenon. 相似文献
50.
J. L. Olsen 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1958,9(3):293-294
Ohne Zusammenfassung 相似文献