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121.
Haolin Zhu Ashish Dhall Subrata Mukherjee Ashim K. Datta 《Transport in Porous Media》2010,84(2):335-369
A thermomechanical theory for multiphase transport in unsaturated swelling porous media is developed on the basis of Hybrid
Mixture Theory (saturated systems can also be modeled as a special case of this general theory). The aim is to comprehensively
and non-empirically describe the effect of viscoelastic deformation on fluid transport (and vice versa) for swelling porous
materials. Three phases are considered in the system: the swelling solid matrix s, liquid l, and air a. The Coleman–Noll procedure is used to obtain the restrictions on the form of the constitutive equations. The form of Darcy’s
law for the fluid phase, which takes into account both Fickian and non-Fickian transport, is slightly different from the forms
obtained by other researchers though all the terms have been included. When the fluid phases interact with the swelling solid
porous matrix, deformation occurs. Viscoelastic large deformation of the solid matrix is investigated. A simple form of differential-integral
equation is obtained for the fluid transport under isothermal conditions, which can be coupled with the deformation of the
solid matrix to solve for transport in an unsaturated system. The modeling theory thus developed, which involves two-way coupling
of the viscoelastic solid deformation and fluid transport, can be applied to study the processing of biopolymers, for example,
soaking of foodstuffs and stress-crack predictions. Moreover, extension and modification of this modeling theory can be applied
to study a vast variety of problems, such as drying of gels, consolidation of clays, drug delivery, and absorption of liquids
in diapers. 相似文献
122.
D. T. Khathing S. P. Tripathy R. Mishra B. K. Verma K. K. Dwivedi 《Radiation measurements》2001,34(1-6):305-308
Heavy ion range and energy-loss data provide useful information for designing several nuclear physics experiments where the polymers employed find their use as absorber, in chamber windows and target backings. In the present work, the range and energy-loss rate of 118 MeV 28Si in LR-115 (cellulose nitrate) and polypropylene (PP) have been calculated by track technique where polyallyldiglycol carbonate was used as a backing detector. The mean range of 28Si in LR-115 has been calculated to be 59.4±2 μm and that in PP is calculated to be 74.9±2 μm. The experimentally evaluated range values are in agreement with the theoretical range values derived from some computer codes. The Bragg peak has also been obtained at 1.1 MeV/nucleon for 28Si in both LR-115 and PP. 相似文献
123.
Amita Singh Archisman Dutta Ashish Kumar Singh Manoj Trivedi Gabriele Kociok-Köhn Mohd. Muddassir Abhinav Kumar 《应用有机金属化学》2020,34(10):e5879
Five new heteroleptic complexes of Cu(I), Ag(I), and Ni(II) having formulae [Cu3(dtc)2(dppf)2]PF6 ( Cu-I ), [Cu3(dtc)2(dppe)2]PF6 ( Cu-II ), [Cu(PPh3)2(dtc)] ( Cu-III ), [Ag3(dtc)2(PPh3)2]NO3 ( Ag-I ), and [Ni(dtc)(dppf)]PF6 ( Ni-I ) (dtc = N-ethanol-N-methylferrocenyl-dithiocarbamate; dppf = 1,1′-bis(diphenylphosphino)ferrocene; dppe = 1,1′-bis(diphenylphosphino)ethane; PPh3 = tripheylphosphine) have been synthesized and characterized using elemental analysis, Fourier-transform infrared, multinuclear nuclear magnetic resonance, UV–Vis spectroscopy, and single-crystal X-ray diffraction. The single-crystal X-ray diffraction studies indicate that Ag-I forms a rare trinuclear cluster in which the geometry around the two silver centers Ag1 and Ag3 is distorted tetrahedral, whereas the third silver center Ag2 shows a distorted trigonal planar geometry. The Ni-I complex has a distorted square-planar geometry around the Ni center. In addition, a side product [Ag2{S2(dppf)2}] ( Ag-II ) was obtained during an attempt to synthesize [Ag(dppf)(dtc)], where the two Ag centers are bridged by two sulfido centers and coordinated with two phosphorus centers of the dppf ligand to give rise to a distorted tetrahedral geometry. The solid-state structures of Ag-I , Ni-I , and Ag-II are stabilized by a variety of weak interactions. The nature of these interactions has been addressed with the help of Hirshfeld surface analyses. In addition, the weak argentophilic interaction in Ag-I and Ag-II have been studied using quantum theory of atoms in molecules and natural bond orbital calculations. The electrochemical properties of the complexes have been investigated using cyclic voltammetry, where Cu-I and Cu-II exhibited two quasi-reversible waves, whereas Cu-III , Ag-I , Ag-II , and Ni-I exhibited only one quasi-reversible peak. 相似文献
124.
The upsurge interest in the development of efficient methodologies for the construction of nitrogen‐containing frameworks via the use of expedient reagents have been creating a renaissance in contemporary organic chemistry. In this perspective, tertbutyl nitrite (TBN) is an emerging building block. Due to its unique structural features, it shows differential reactivity under different reaction conditions. These diverse reactivities have resulted in the construction of a diverse array of complex N‐containing molecules. The primary objective of the present review is to bring the latest findings of TBN in terms of its applications in reactions (oxidation, diazotization, nitrosation, nitration, oximation, N‐synthon, and miscellaneous reactions) into the limelight. For simplicity and brevity, reactions in each section are explained with the mechanism of formation and selected examples are given. 相似文献
125.
Kilby Seth Jin Zhongmin Avachat Ashish Kanies Bryant Woolstenhulme Nicolas Lee Hyoung K. Graham Joseph 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(1):445-446
Journal of Radioanalytical and Nuclear Chemistry - In the original article, Equation 4 was incorrectly published. The correct equation is provided in this correction 相似文献
126.
In recent years, angular and linear phenoxazines and their derivatives and polymers have attracted much attention due to their great pharmacological and industrial utility. So it becomes imperative to review the work done in this area more frequently. Therefore, various synthetic routes for phenoxazines are reviewed here comprehensively. 相似文献
127.
Considering the Boltzmann response of the plasma ions and electrons and inertial dynamics of the charged dust grains, the
possibility of very weak compressive soliton near the continuum limit of the dust population has been inferred. It is concluded
that the behaviour of such coherent structures could be well described by the numerical analysis of the derived nonlinear
classical energy integral equation for bounded solutions. These seem to be higher order dispersive structures within acoustic
limit of the nonlinear turbulence. It is observed that the dust density enhancement beyond the continuum threshold causes
regular increment in width and amplitude of the soliton structures. It is found that the soliton amplitude sensitively depends
on the massive impurity’s population. These coherent structures could be visualized as weakly charged solitary dust clouds
of finite extension (∼ plasma Debye length) within Boltzmann environment of plasma particles in their local surroundings.
The seeding mechanism of such clouds may be attributed to some plasma instabilities driven by either internal or external
free energy sources. Numerical analysis of the problem concludes that the experimental observations of such clouds could be
possible in low density plasma regime. It is deduced that for plasma density ∼ 106 cm-3 at temperatures of a few electron volts and for micron to l0nm sized dust grains, the observation of such structures could
be possible within wide range variability of the dust population density. 相似文献
128.
The variation of the range of 2.72 GeV 209Bi with crystalline anisotropy has been studied using an anisotropic detector - muscovite mica and an isotropic detector - polycarbonate (Bayer). The two detectors were irradiated at five different angles ranging between 15° and 75°. The effect of the crystal structure on the range variance has also been discussed. 相似文献
129.
M. Ochs I. G. Abdullaev I. Adam J. C. Adloff I. G. Bersina V. Bradnova R. Brandt M. Bognitzki V. S. Butsev M. Debeauvais K. K. Dwivedi F. Fernandes S. -L. Guo M. I. Krivopustov B. A. Kulakov E. -J. Langrock G. Modolo R. Odoj V. P. Perelygin A. N. Priemyshev V. S. Pronskich T. Schmidt A. N. Sosnin V. I. Stegailov R. Sudowe P. Vater J. -S. Wan M. Zamani V. M. Zupko-Sitnikov 《Radiation measurements》1997,28(1-6):255-268
Extended targets were irradiated for transmutation studies with relativistic heavy ions. For this, a metal core was surrounded by a paraffin moderator. The metal is either copper or lead and it was irradiated with deuterium, alpha, or carbon beams of 1.5 or 3.7 GeV/u at the SYNCHROPHASOTRON, LHE, JINR, Dubna, Russia. During this irradiation copious amounts of secondary neutrons are produced and studied with SSNTD detectors and radiochemical sensors, for example 139La (n, γ) 140La→β−. The yield of reaction products allows an estimation of secondary neutron fluxes. The yields of all kinds of reactions produced with deuterium and alpha beams obey to some extent the law of “limiting fragmentation”, i.e. they show little influence on the energy and the kind of incoming particles. However, one observes with 44 GeV 12C ions always enhanced nuclear cross-sections induced by secondary particles. This behavior could not be confirmed with theoretical estimations based on the Dubna Cascade Model in its Cascade Evaporation Model version (DCM-CEM). Finally, some results for transmutation studies on 127I and Cu will be presented. 相似文献
130.
Summary The present paper reports a study of photocrystallization in a-Se70Te30−xCdx films (0≤x≤4). The photocrystallization is achieved by shining white light at room temperature for different exposure times.
The results indicate that the photocrystallization is suppressed on addition of Cd in binary Se70Te30 system. This is explained in terms of the structure of Se-Te-Cd system.
Work supported by University Grants Commission.
The authors of this paper have agreed to not receive the proofs for correction. 相似文献