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21.
Single crystals of MoSe2 of fairly large size have been grown by the sublimation method. A careful study of microstructures on the as-grown faces has revealed a variety of surface patterns. All these features have been critically studied and the implications have been discussed. 相似文献
22.
Response surface methodology (RSM) was employed for optimization of medium components and cultural parameters in cost effective
cane molasses based medium for attaining high yield of succinic acid. The important factors obtained by “one-variable-at-a-time-approach”
(cane molasses, corn steep liquor, sodium carbonate, and inoculum density) were further optimized by RSM. The optimum values
of the parameters obtained through RSM (cane molasses 12.5%, corn steep liquor 7.5%, and sodium carbonate 25 mM) led to almost
double yield of succinic acid (15.2 g/l in 36 h) as against “one-variable-at-a-time-approach” (7.1 g/l in 36 h) in 500-ml
anaerobic bottles containing 300-ml cane molasses based medium. Subsequently, in 10-l bioreactor succinic acid production
from Escherichia coli was further improved to 26.2 g/l in 30 h under conditions optimized through RSM. This fermentation-derived succinic acid
will definitely help in replacing existing environmentally hazardous and cost-intensive chemical methods for the production
of succinic acid. 相似文献
23.
R. K. Sinha A. Dhal P. Agarwal S. Kumar Monika B. B. Singh R. Kumar P. Bringel A. Neusser R. Kumar K. S. Golda R. P. Singh S. Muralithar N. Madhavan J. J. Das K. S. Thind A. K. Sinha I. M. Govil R. K. Bhowmik J. B. Gupta P. K. Joshi A. K. Jain S. C. Pancholi L. Chaturvedi 《The European Physical Journal A - Hadrons and Nuclei》2006,28(3):277-281
High-spin states in 79Rb were populated in the reaction
at E(beam) = 60 MeV. The lifetimes of the excited states of the
positive-parity yrast band and of the
negative-parity band in 79Rb were measured by the Doppler Shift Attenuation Method. The deduced transition quadrupole moments Qt are found to have a decreasing trend with rotational frequency for both the bands, consistent with those found experimentally
in neighbouring nuclei.
An erratum to this article is available at . 相似文献
24.
In this paper thermal performance of graphite-based sensible heat storage system with embedded helical coil in rectangular shell was studied. Plain water at four flow rates (0.25 LPM–1.0 LPM) and four inlet temperatures (60°C–90°C) was passed through the graphite bed and charging time was measured. Expanded graphite/water suspension and Al2O3/water nanofluid were also used to study charging behavior of graphite. Results showed that charging time of packed bed was reduced with increase in flow rate and inlet temperature of heat transfer fluid. Charging time using expanded graphite/water solution and nanofluid was 14.2% and 21.2% lesser than water.Abbreviations: hi: internal heat transfer coefficient (W m?2 K?1); HTF: Heat transfer fluid; ho: External heat transfer coefficient (W m?2 K?1); LPM: liter per minute; k: thermal conductivity (W m?1 K?1); TSU: Thermal storage unit 相似文献
25.
Agarwal GS 《Physical review letters》2000,84(24):5500-5503
We demonstrate how the anisotropy of the vacuum of the electromagnetic field can lead to quantum interferences among the decay channels of close lying states. Our key result is that interferences are given by the scalar formed from the antinormally ordered electric field correlation tensor for the anisotropic vacuum and the dipole matrix elements for the two transitions. We present results for emission between two conducting plates as well as for a two photon process involving fluorescence produced under coherent cw excitation. 相似文献
26.
We investigate the unsteady state temperature distribution in human skin where subcutaneous tissues are not present. The mathematical model is employed for a onedimensional unsteady state case, taking the blood mass flow rate and metabolic heat generation variable with respect to the position in the dermis. The metabolic heat generation depends on the tissue temperature. The thermal conductivity is taken constant but different in two layers. The problem has been solved using Laplace transform and Bessel functions. Numerical results for a simple case are discussed. 相似文献
27.
Journal of Statistical Physics - In this work we discuss connections between a one-dimensional system of N particles interacting with a repulsive inverse square potential and confined in a harmonic... 相似文献
28.
Over the last decade, the synthetic chemist's community has attracted attention towards aldo-x precursors due to their versatility to afforded variety of heterocyclic frameworks. The aldo-x bifunctional building blocks (AXB3s) contain two or more reactive sites with different reactivity, which may offer new opportunities for the introduction of diversity in core skeleton, which may be of great biological and medicinal relevance. In this context, pyrazole based AXB3s such as 4-iodopyrazole-3/5-carbaldehyde may be explored for achieving pyrazole fused/linked heterocyclic skeletons by employing different organic transformations. Specifically, iodo substituted pyrazoles provide a new platform for the installation of desired pattern via transition-metal catalyzed approaches. Herein, we have assembled the strategies towards the development of pyrazole substituted and fused molecular architectures by using 4-iodopyrazole-3/5-carbaldehydes and pyrazole C-3)/C5- carbaldehydes. The photophysical data of some fluorescent pyrazole derivatives have also been discussed. 相似文献
29.
30.
Shubham Deolka Ramadoss Govindarajan Serhii Vasylevskyi Michael C. Roy Julia R. Khusnutdinova Eugene Khaskin 《Chemical science》2022,13(44):12971
We describe a “ligand-free” Ni-catalyzed perfluoroalkylation of heteroarenes to produce a diverse array of trfiluoromethyl, pentafluoroethyl and heptafluoropropyl adducts. Catalysis proceeds at room temperature via a radical pathway. The catalytic protocol is distinguished by its simplicity, and its wide scope demonstrates the potential in the late-stage functionalization of drug analogues and peptides.A ligand-free, room temperature, Ni-catalyzed perfluoroalkylation of heteroarenes produced a diverse array of polyfluorinated adducts; potential in the late-stage functionalization of drugs and peptides is also demonstrated. 相似文献