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51.
Analytical models for virus transport in saturated, homogeneous porous media are developed. The models account for three-dimensional dispersion in a uniform flow field, and first-order inactivation of suspended and deposited viruses with different inactivation rate coefficients. Virus deposition onto solid particles is described by two different processes: nonequilibrium adsorption which is applicable to viruses behaving as solutes; and colloid filtration which is applicable to viruses behaving as colloids. The governing virus transport equations are solved analytically by employing Laplace/Fourier transform techniques. Instantaneous and continuous/periodic virus loadings from a point source are examined. 相似文献
52.
Isolation and structure determination of a novel furanic ester from the aerial part of Prasium majus
The aerial part of Prasium majus provided a new furanic ester, 2-2-[(5-formyl-6[(5-formylfuran-2-yl)methoxy] succinic acid dimethyl ester, (+/-)-hiziprafuran. Its structure was principally established by one- and two-dimensional NMR spectroscopy. 相似文献
53.
Cho S Youn SJ Kim Y DiVenere A Wong GK Freeman AJ Ketterson JB 《Physical review letters》2001,87(12):126403
We have observed an epilayer-thickness-dependent polarity inversion for the growth of CdTe on Sb(Bi)/CdTe(111)B. For films with Sb(Bi) thicknesses of less than 40 A (15 A), the CdTe layer shows a B (Te-terminated) face, but it switches to an A (Cd-terminated) face for thicker layers. On the other hand, a CdTe layer grown on Bi(Sb)/CdTe(111)A always shows the A face regardless of Sb or Bi layer thicknesses. In order to address the observations we have performed ab initio calculations, which suggest that the polarity of a polar material on a nonpolar one results from the binding energy difference between the two possible surface configurations. 相似文献
54.
55.
Ing Youn Chen Chih-Yung Tseng Yur-Tsai Lin Chi-Chuan Wang 《International Journal of Multiphase Flow》2009
This study investigates the pressure change and flow pattern subject to the influence of sudden contractions. The air and water mixture flows from small rectangular channels (2 × 4, 2 × 6, 4 × 4 and 4 × 6 mm, respectively) into a 2 mm diameter tube. The total mass flux (G) ranges from 100 to 700 kg/m2 s with gas quality (x) being varied from 0.001 to 0.8. In general the contraction pressure change increases with the rise of mass flux, and gas quality but an unique deflection of contraction pressure change pertaining to liquid vena contracta at a very low gas quality is encountered at a very low gas quality in the 4 ± 6 mm test section. For a low gas quality, elongated bubble prevails after the contraction, yet the size of elongated bubbles is reduced when the aspect ratio is increased. Comparisons amid the pressure change data of this study and available literature data with the predictions of existing model/correlations indicate that none of them can accurately predict the data. It is found that the influence of surface tension and outlet tube size, or equivalently the Bond number plays a major role for the departure of various models/correlations. Among the models/correlations being examined, the homogeneous model shows a little better than the others. Hence by taking account the influences of gas quality, Bond number, Weber number and area contraction ratio into the homogeneous model, a modified homogeneous correlation is proposed that considerably improves the predictive ability over existing correlations with a mean deviation of 30% to all the data. 相似文献
56.
Samit Mandal J Gerl H Geissel K Hauschild M Hellström Z Janas I Kojouharov Y Kopatch RC Lemmon P Mayet Z Podolyak PH Regan H Schaffner C Schlegel J Simpson HJ Wollersheim 《Pramana》2001,57(1):161-164
Feasibility of gamma-ray spectroscopy at relativistic energies with exotic heavy-ions and new generation of germanium detectors
(segmented Clover) is discussed. An experiment with such detector array and radioactive is discussed. 相似文献
57.
58.
HJ. Mellin 《Acta Mathematica》1886,8(1):37-80
Ohne Zusammenfassung
Vergl. meine Abhandlung:Om en ny klass af transcendenta functioner, hvilka ?ro n?ra besl?gtade med gammafunktionen, Acta soc. scient. Fennic?, Tom. XIV, XV; 1885, 1886. 相似文献
59.
Prof. Dr. So Won Youn Tae Yun Ko Young Ho Jang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(23):6736-6740
A Pd-catalyzed intermolecular oxidative annulation between N-Ts-anilines and styrenes was developed. This method offers a straightforward and robust approach to a wide range of 3-arylindoles using readily available starting materials with good functional-group tolerance and high regioselectivity and efficiency. Further elaboration of the products obtained from this process provided access to highly functionalized and structurally diverse indoles, for example, 3-(indol-3-yl)carbazoles, 1,9-dihydropyrrolo-[2,3-b]carbazoles, and 3′-aryl-3,5′-biindoles. 相似文献
60.
Heat and Mass Transfer in MHD Micropolar Flow Over a Vertical Moving Porous Plate in a Porous Medium
Youn J. Kim 《Transport in Porous Media》2004,56(1):17-37
An analysis is presented for the problem of free convection with mass transfer flow for a micropolar fluid via a porous medium bounded by a semi-infinite vertical porous plate in the presence of a transverse magnetic field. The plate moves with constant velocity in the longitudinal direction, and the free stream velocity follows an exponentially small perturbation law. A uniform magnetic field acts perpendicularly to the porous surface in which absorbs the micropolar fluid with a suction velocity varying with time. Numerical results of velocity distribution of micropolar fluids are compared with the corresponding flow problems for a Newtonian fluid. Also, the results of the skin-friction coefficient, the couple stress coefficient, the rate of the heat and mass transfers at the wall are prepared with various values of fluid properties and flow conditions. 相似文献