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61.
Goldstein Irving S. Bayat-Makooi Fred Sabharwal H. S. Singh T. M. 《Applied biochemistry and biotechnology》1989,(1):95-106
Satisfactory separation of either hydrochloric or sulfuric acid from sugars in wood hydrolyzates by application of membrane
technology is technically feasible. The permeability of disaccharides is less than 1% that of the acids. Acid flux in diffusion
dialysis is only 6% of acid flux at optimum current density in electrodialysis. Critical parameters for economic feasibility
are acid to wood ratio in hydrolysis, current efficiency, and membrane service life. Best case estimates project total costs
for sulfuric acid recovery and loss of about $0.02 per pound of glucose produced. 相似文献
62.
Wong KL Chu MS Luce TC Petty CC Politzer PA Prater R Chen L Harvey RW Austin ME Johnson LC La Haye RJ Snider RT 《Physical review letters》2000,85(5):996-999
Experimental evidence is reported of an internal kink instability driven by a new mechanism: barely trapped suprathermal electrons produced by off-axis electron cyclotron heating on the DIII-D tokamak. It occurs in plasmas with an evolving safety factor profile q(r) when q(min) approaches 1. This instability is most active when ECCD is applied on the high field side of the flux surface. It has a bursting behavior with poloidal/toroidal mode number = m/n = 1/1. In positive magnetic shear plasmas, this mode becomes the fishbone instability. This observation can be qualitatively explained by the drift reversal of the barely trapped suprathermal electrons. 相似文献
63.
Focsa C Poclet A Pinchemel B Le Roy RJ Bernath PF 《Journal of Molecular Spectroscopy》2000,203(2):330-338
The A'(1)Pi-X(1)Sigma(+) near-infrared system of CaO was observed for the first time at high resolution using a Fourier transform spectrometer. The A'(1)Pi-X(1)Sigma(+) chemiluminescence was excited in a Ca + N(2)O flame produced in a Broida-type oven. More than 3000 rotational lines, classified into 19 bands involving the A'(1)Pi 0 = v' = 3 and the X(1)Sigma(+) 1 = v" = 7 vibrational levels were measured in the 4000-10 000 cm(-1) region with a precision of 0.005 cm(-1). The X(1)Sigma(+) (v = 0, 1) millimeter-wave and X(1)Sigma(+) (v = 0-3) infrared data available in the literature were merged with our new electronic data in order to obtain improved Dunham constants for the ground state of CaO. Very peculiar perturbations are observed in the higher vibrational levels of the A'(1)Pi state, so the upper levels of transitions with v' = 2 and 3 were represented by term values in our least-squares analysis. The interaction of the A'(1)Pi (v >/= 2) levels with the nearby b(3)Sigma(+) (v-2) levels has been detected. An extended set of A'(1)Pi (v = 0-3) data has been obtained which is suitable for use in a future multistate deperturbation analysis of the a(3)Pi approximately A'(1)Pi approximately b(3)Sigma(+) approximately A(1)Sigma(+) complex of excited states. The new near-infrared spectra of the A'(1)Pi-X(1)Sigma(+) transition of CaO also permits the first direct high-resolution linkage between the orange and green systems and the near-infrared bands. Copyright 2000 Academic Press. 相似文献
64.
65.
The backscattered peak and albedos are important for the estimation of exposure distribution and for better understanding the phenomenon of the backscattering of gamma photons. To characterize the backscattering probability of gamma photons interacting with different atomic numbers (Z), number (A N), energy (A E) and dose (A D) albedos are experimentally evaluated. The response function converts the observed pulse-height distribution of a NaI(Tl) scintillation detector to a true photon spectrum. For each of the incident gamma photon energies, the number and energy albedos show an increase with the increasing target thickness, and finally saturate. The energy albedos are found to be decreasing with the increase in the atomic number of the target material and incident gamma photon energy. The dose albedos do not differ significantly from the energy albedos for the chosen incident gamma photon energies. 相似文献
66.
Sanjeev Kumar Bikramjit S. Bajwa Arvind D. Sabharwal 《Isotopes in environmental and health studies》2013,49(4):446-455
Radon concentration levels in water and soil gas from 36 locations pertaining to some areas of Malwa region of Punjab have been measured on an in situ basis using a continuous active radon detector (AlphaGuard, Model – PQ 2000 PRO, Genitron instruments, Germany). Exhalation rate measurements have also been carried out at these places, using a closed-circuit technique. The radon concentrations in soil and water varied from 1.9 to 16.4 kBq m?3 and 5.01 to 11.6 kBq m?3, respectively. The exhalation rate (E Rn) ranged between 7.48 and 35.88 mBq m?2 s?1 with an average value of 18.17 mBq m?2 s?1. Annual dose rates have been calculated for water radon concentrations. The minimum to maximum values of dose rates were found to be 13.42–31.08 μSv y?1. The recorded values of radon concentration in water are within the safe limit of 11 Bq l?1 recommended by the US Environment Protection Agency [National Research Council, Risk Assessment of Radon in Drinking Water (Academy Press, Washington, DC, USA, 1999)]. All measurements were made in similar climatic and environmental conditions to ensure minimal variations in meteorological parameters. An intermediate correlation coefficient (0.5) was observed between radon exhalation rates and soil gas values. 相似文献
67.
S. K. Gupta V. R. Katti D. P. Gandhi D. K. Aswal S. C. Sabharwal M. K. Gupta 《Phase Transitions》2013,86(1-2):125-130
Anomalies in the resistance versus temperature plots of some Y-Ba-Cu-O sputtered thin films have been observed. Compositional variations over some portion of the film are found responsible for the appearance of the anomalies. The need for exercising caution in the interpretation of such anomalies is emphasized. 相似文献
68.
S. C. Gadkari K. P. Muthe K. D. Singh S. C. Sabharwal M. K. Gupta 《Applied Physics A: Materials Science & Processing》1989,49(3):331-334
The preparation of ceramic superconductors based on the Bi-Sr-Ca-Cu-O system in a reproducible manner with zero-resistance transition temperatures (T
c) tailored between 65 and 85 K is described. Partial melting of the sample pellet during preparation helps in raising itsT
c. Thick crystallographically oriented films of the material withT
c=77 K have been prepared on sintered SrTiO3 substrates. 相似文献
69.
Karanjule NS Markad SD Sharma T Sabharwal SG Puranik VG Dhavale DD 《The Journal of organic chemistry》2005,70(4):1356-1363
[reaction: see text] The synthesis and evaluation of glycosidase inhibitory activity of polyhydroxylated indolizidine alkaloids namely 2-hydroxy-1-deoxycastanospermine 3a,b and 2-hydroxy-1-deoxy-8a-epi-castanospermine 3c,d is reported. The key step involves the intermolecular 1,3-dipolar cycloaddition of allyl alcohol to d-glucose-derived nitrone 4, followed by tosylation, that afforded four diastereomeric sugar-substituted isoxazolidines 5a-d with the desired regioselectivity. The one-pot conversion of 5a-d to pyrrolidines 8a-d by hydrogenolysis, removal of 1,2-acetonoide functionality, and hydrogenation afforded corresponding target molecules 3a-d. 相似文献
70.
An efficient strategy for the synthesis of 5-hydroxy substituted isofagomine analogues and , having both -CH2OH/CH3 and -OH functionality at the C-5 position, and evaluation of their inhibitory potency is reported. The synthetic methodology involves the aldol-Cannizzaro reaction of easily available alpha-d-xylopentodialdose followed by hydrogenolysis to afford the triol . Selective amidation of the alpha- and beta-hydroxymethyl group at C-4, deprotection of the 1,2-acetonide group and hydrogenation gave the target molecules, which were found to be potent against beta-glycosidases with IC50 values in the micro molar range. Compound showed excellent potency against glycosidases and human salivary amylase. 相似文献