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51.
52.
Apparent molar adiabatic compressibilities (K?, s) of glycine, L-alanine, L-valine, and L-leucine have been determined in aqueous and mixed aqueous solutions of lactose (2 to 6 mass%) at T = (293.15, 298.15, 303.15, and 308.15) K. From these data partial molar adiabatic compressibilities at infinite dilution (K?, s0) have been evaluated to calculate corresponding transfer function. The transfer partial molar adiabatic compressibilities at infinite dilution (ΔK?, s0) are found to be positive. The decrease in the magnitude of transfer partial molar adiabatic compressibilities from glycine to L-leucine indicates the dominance of hydrophobic-hydrophobic interactions between the increasing side chains of amino acids. Also, the contributions of NH3+COO− , and CH2 groups have been calculated by the linear correlation of K?, s0 with number of carbon atoms in the alkyl chain of amino acids. 相似文献
53.
Narendra P. S. Chauhan 《Journal of Thermal Analysis and Calorimetry》2012,110(3):1377-1388
A terpolymer resin involving p-acetylpyridine oxime and p-methylacetophenone with formaldehyde (APOMAF) was synthesized by condensation polymerization in the presence of an acid catalyst. The structure of terpolymer was elucidated by FT-IR, 1H NMR, pyrolysis gas chromatography mass spectrometer (Py?CGC?CMS), nitrogen adsorption/desorption analysis, Ubbelohde viscometer and non-aqueous conductometric titration, TG?CDTG and DSC. Molar fractions of monomer, condensing and comonomer unit (m 1, m 2, and m 3) in APOMAF using 1H NMR analysis data were calculated as 1.67; 0.27 and 0.66?mol%, respectively. The apparent activation energy of terpolymer by using various degradation models including the Flynn?CWall?COzawa (FWO), Kissinger?CAkahira?CSunose (KAS), and Friedman methods were 140.3; 144.9 and 129.9?kJ?mol?1, respectively. The results from isoconversional degradation kinetics and Pyrolysis (GC?CMS) indicates that the degradation mechanism of terpolymer are likely limited by at least two-reaction step, the first being associated with the loss of the pendent methyl, acetyl, and oxime groups (side group elimination) while the second mass loss being due to the degradation of the terpolymer backbone (random scission) which clearly indicates that grafting pendant groups to the terpolymer backbone yields polymers with lower thermal stability. From the calculation, the solid state thermal degradation mechanism is proposed to be D3 (three-dimensional diffusion) at initial stage and F 1 (Random nucleation with one nucleus on the individual particles) at final stage. 相似文献
54.
Satyaveer S. Chauhan 《Operations Research Letters》2005,33(3):249-254
The supply scheduling problem consists in finding a minimum cost delivery plan from a set of providers to a manufacturing unit, subject to given bounds on the shipment sizes and subject to the demand at the manufacturing unit. We provide a fully polynomial time approximation scheme for this problem. 相似文献
55.
Discrimination of bacteria from Jamaican bauxite soils using laser-induced breakdown spectroscopy 总被引:1,自引:0,他引:1
Lewis DE Martinez J Akpovo CA Johnson L Chauhan A Edington MD 《Analytical and bioanalytical chemistry》2011,401(7):2225-2236
Soil bacteria are sensitive to ecological change and can be assessed to gauge anthropogenic influences and ecosystem health.
In recent years, there has been a significant increase in the focus on new technologies that can be applied to the evaluation
of soil quality. Laser-induced breakdown spectroscopy (LIBS) is a promising technique that has been used for the investigation
and characterization of explosives, solids, liquids, gases, biological and environmental samples. In this study, bacteria
from un-mined and a chronosequence of reclaimed bauxite soils were isolated on Luria–Bertani agar media. Polymerase chain
reaction amplification of the bacterial 16S rDNA, sequencing, and phylogenetic analysis were applied to each isolated soil
bacteria from the sample sites resulting in the identification and classification of the organisms. Femtosecond LIBS performed
on the isolated bacteria showed atomic and ionic emission lines in the spectrum containing inorganic elements such as sodium
(Na), magnesium (Mg), potassium (K), zinc (Zn), and calcium (Ca). Principal component analysis and partial least squares regression
analysis were performed on the acquired bacterial spectra demonstrating that LIBS has the potential to differentiate and discriminate
among bacteria in the un-mined and reclaimed chronosequence of bauxite soils. 相似文献
56.
We consider a two-echelon timber supply chain in which the first echelon consists of several stands to be harvested and the
second echelon consists of mills to be supplied with logs of different length. This problem aims at minimizing harvesting
and transportation costs for one production period, while satisfying demand expressed as a mix of volumes of specific log
types. Harvesting cost, which includes felling, bucking and hauling to roadside, depends upon the number of log type to be
produced and sorted. Each stand to be harvested is modeled individually with a limited number of trees of various classes
of diameter and total length, which affects the productivity factors of the bucking patterns to be used. To take these characteristics
into account, we propose heuristics based on columns generation to solve the supply network problem at the forest level with
an anticipation of bucking operations at the stand level. 相似文献
57.
We consider a two-phase model of melt spinning including flow induced crystallization. Introducing slight modifications in the model we perform numerical simulations on it. We present comparison of our velocity profiles with the experimental profiles provided by the company Freudenberg & Co. 相似文献
58.
Graphite oxide and graphene oxides have been used as solid catalysts for the synthesis of 5,5-dialkyldipyrromethanes and calix[4]pyrroles in organic and aqueous solutions at room temperature. 相似文献
59.
Chauhan Varsha Sharma Anuradha Sharma Sandeep Yadav Monika 《Designs, Codes and Cryptography》2021,89(8):1787-1837
Designs, Codes and Cryptography - Let $${\mathbb {F}}_q$$ denote the finite field of order q, and let $$n = m_1+m_2+\cdots +m_\ell ,$$ where $$m_1,m_2,\ldots ,m_\ell $$ are arbitrary... 相似文献
60.
Sunil K. Singhal Veeresh Kumar K. Stalin Amit Choudhary Satish Teotia Gade B. Reddy Rakesh B. Mathur Surinder P. Singh Renu Pasricha 《Particle & Particle Systems Characterization》2013,30(5):445-452
Synergetic cooperation of individual components of the nanocomposites (NCs) is responsible for their novel properties that lead to various technological applications. A simple chemical process depicting the deposition of functionalized gold nanoparticles on the surface of boron nitride nanosheets (BNNSs) in solution is reported. The structure, chemical composition, and optical properties of nanosheets are systematically studied. The deposition of Au nanoparticles on BNNS (BNNSAu) results in plasmonic band modulation, thus altering the optoelectronic properties of BNNSs. The intense surface plasmon absorption band of BNNSAu is narrowed and red‐shifted relative to the absorption band of as synthesized monometallic BNNSs. The observations reflect the strong interfacial interaction between BNNS and Au nanoparticles. This approach constitutes a basis for a simple process leading to the preparation of functionalized BNNSs and their utilization as nanoscale templates for assembly and integration with other nanoscale materials for futuristic optoelectronic devices. 相似文献