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101.
The Cox–Merz rule and Laun’s rule are two empirical relations that allow the estimation of steady shear viscosity and first normal stress difference, respectively, using small amplitude oscillatory shear measurements. The validity of the Cox–Merz rule and Laun’s rule imply an agreement between the linear viscoelastic response measured in small amplitude oscillatory shear and the nonlinear response measured in steady shear flow measurements. We show that by using a lesser-known relationship also proposed by Cox and Merz, in conjunction with Laun’s rule, a relationship between the rate-dependent steady shear viscosity and the first normal stress difference can be deduced. The new empirical relation enables a priori estimation of the first normal stress difference using only the steady flow curve (i.e., viscosity vs shear rate data). Comparison of the estimated first normal stress difference with the measured values for six different polymer solutions and melts show that the empirical rule provides values that are in reasonable agreement with measurements over a wide range of shear rates, thus deepening the intriguing connection between linear and nonlinear viscoelastic response of entangled polymeric materials. 相似文献
102.
Vivek?Kandiah Bertrand?Georgeot Olivier?GiraudEmail author 《The European Physical Journal B - Condensed Matter and Complex Systems》2014,87(10):246
We analyze the game of go from the point of view of complex networks. We construct three different directed networks of increasing complexity, defining nodes as local patterns on plaquettes of increasing sizes, and links as actual successions of these patterns in databases of real games. We discuss the peculiarities of these networks compared to other types of networks. We explore the ranking vectors and community structure of the networks and show that this approach enables to extract groups of moves with common strategic properties. We also investigate different networks built from games with players of different levels or from different phases of the game. We discuss how the study of the community structure of these networks may help to improve the computer simulations of the game. More generally, we believe such studies may help to improve the understanding of human decision process. 相似文献
103.
104.
A total of 49 protein sequences of alkaline proteases retrieved from GenBank representing different species of Aspergillus have been characterized for various physiochemical properties, homology search, multiple sequence alignment, motif, and super
family search and phylogenetic tree construction. The sequence level homology was obtained among different groups of alkaline
protease enzymes, viz alkaline serine protease, oryzin, calpain-like protease, serine protease, subtilisin-like alkaline proteases.
Multiple sequence alignment of alkaline protease protein sequence of different Aspergillus species revealed a stretch of conserved region for amino acid residues from 69 to 110 and 130–204. The phylogenetic tree
constructed indicated several Aspergillus species-specific clusters for alkaline proteases namely Aspergillus fumigatus, Aspergillus niger, Aspergillus oryzae, Aspergillus clavatus. The distributions of ten commonly observed motifs were analyzed among these proteases. Motif 1 with a signature amino acid
sequence of 50 amino acids, i.e., ASFSNYGKVVDIFAPGQDILSCWIGSTTATNTISGTSMATPHIVGLSCYL, was uniformly observed in proteases
protein sequences indicating its involvement with the structure and enzymatic function. Motif analysis of acidic proteases
of Aspergillus and bacterial alkaline proteases has revealed different signature amino acid sequences. The superfamily search for these
proteases revealed the presence of subtilases, serine-carboxyl proteinase, calpain large subunit, and thermolysin-like superfamilies
with 45 representing the subtilases superfamily. 相似文献
105.
John Texter Vivek Arjunan Vasantha Rene Crombez Rafael Maniglia Lisa Slater Thomas Mourey 《Macromolecular rapid communications》2012,33(1):69-74
The controlled atom transfer radical polymerization of an ionic liquid, 1‐(11‐acryloylundecyl)‐3‐methyl imidazolium bromide (ILBr), from both ends of a telechelic poly(propylene oxide) (PPO) macroinitiator, end‐functionalized with bromoisobutyryloyl is reported. The resulting highly water‐soluble triblock, poly(ILBr‐b‐PO‐b‐ILBr) is multistimuli responsive. This new class of triblocks exhibits classical surface activity in lowering surface tension at the air–water interface and in modifying wetting in waterborne coatings. It also immunizes model colloids against coagulation induced by Debye–Hückel (indifferent electrolyte) electrostatic screening. Further, sol–gel thermoreversibility is unexpectedly found as an additional form of stimuli responsiveness. 相似文献
106.
An averaged system to approximate the slow dynamics of a two timescale nonlinear stochastic control system is introduced.
Validity of the approximation is established. Special cases are considered to illustrate the general theory. 相似文献
107.
In this note a dual problem is formulated for a given class of disjunctive linear fractional programming problems. This result generalizes to fractional programming the duality theorem of disjunctive linear programming originated by Balas. Two examples are given to illustrate the result. 相似文献
108.
Sundaravel Vivek Kumar Mani Anusha Rani Abdulrahman I. Almansour Raju Suresh Kumar S. Athimoolam Raju Ranjith Kumar 《Tetrahedron》2018,74(35):4569-4577
A facile syntheses of novel poly-substituted pyridine/benzo fused cyclododecane hybrid heterocycles have been achieved through one-pot multi-component tandem strategy employing cyclododecanone, aromatic aldehydes and malononitrile. 相似文献
109.
Kinetic investigations on interaction of carbon monoxide with RuIICl2(PPh3)3 in mixed aqueous medium
Vivek K. Srivastava Ram S. Shukla Sharad D. Bhatt Raksh V. Jasra 《Reaction Kinetics and Catalysis Letters》2004,81(1):99-105
Kinetics, equilibrium and thermodynamics of interaction of CO with RuCl2(PPh3)3 (1) have been investigated in 1:1(v/v) water — 1,4-dioxan mixture in which 1 dissociates to RuCl2(PPh3)2 (1a), by losing a coordinated PPh3. The kinetics of complexation of (1a) with CO to form RuCl2(CO)(PPh3)2 (2) indicated first order dependence in [1a] and [CO]. The thermodynamic parameters for the formation of 2 were determined.This revised version was published online in December 2005 with corrections to the Cover Date. 相似文献
110.
There has been an increasing awareness conceming the adequacy of trace elements in diet as their deficiency or excess may cause abnormal changes in the biochemical processes. Typical Indian vegetarian diet and dietary components such as cereals, grains, pulses, vegetables and spices have been analysed for 19 elements (Br, Cl, Co, Cr, Cu, Fe, Hg, K, Mn, Mo, Na, P, Rb, Sb, Sc, Se, Sr, Th and Zn) by instrumental neutron activation analysis (INAA). Several Standard Reference Materials (SRMs) were analysed for quality assurance. Based on the elemental contents, the daily dietary intake has been calculated and the data compared with those from other countries, Recommended Dietary Allowances (RDAs) and permissible body burden. It has been observed that, although vegetarian, the Indian diet has an adequate content of essential trace elements compared to non-vegetarian oriental (Japan and Taiwan) and western (Germany, Denmark and USA) diets. 相似文献