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1.
V Ravindran Pankaj Agrawal Rahul Basu Satyaki Bhattacharya J Blümlein V Del Duca R Harlander D Kosower Prakash Mathews Anurag Tripathi 《Pramana》2006,67(5):983-992
This is the report of the subgroup QCD of Working Group-4 at WHEPP-9. We present the activities that had taken place in the
subgroup and report some of the partial results arrived at following the discussion at the working group meetings. 相似文献
2.
We give an overview of studies of models for semiflexible, equilibrium polymers with special emphasis on our work on both lattice and continuum models for such systems. We show, principally by Monte Carlo simulations, that, once monomers self assemble to form polymers, their semiflexibility leads to nematic phases at low temperatures. Attractive wall potentials encourage the adsorption of these equilibrium polymers on surfaces. Rapid cooling leads to the formation of glasses with entangled polymers. Shear promotes nematic ordering, but, at high shear rates, this tendency decreases since the equilibrium polymers are torn apart. A version of our model in which the polymers are directed shows the polymer analog of bosonic Mott-insulating, mass-density-wave, and supersolid phases. We give a brief comparison of our work with other studies and also explore the experimental implications of our study. 相似文献
3.
We consider the effects of quark masses to the perturbative thrust in e
+
e
− annihilation. In particular we show that perturbative power corrections resulting from non-zero quark masses considerably
alters the size of the non-perturbative power corrections and consequently, significantly changes the fitted value of αs. 相似文献
4.
For an innovative product characterized by short product lifecycle and high demand uncertainty, investment in capacity buildup has to be done cautiously. Otherwise either the product’s market diffusion is impeded or the manufacturer is left with unutilized capacity. Using the right information for making capacity augmentation decisions is critical in facing this challenge. In this paper, we propose a method for identifying critical information flows using the system dynamics model of a two-echelon supply chain. The fundamental premise of system dynamics methodology is that (system) structure determines (its) behavior. Using loop dominance analysis method we study the feedback loop structure of the supply chain system. The outcome is a set of dominant loops that determine the dynamics of capacity growth. It is revealed that the delivery delay information has little effect while the loop that connects retail sales with production order affects the dynamics significantly. Modifying this loop yields appropriate capacity augmentation decisions resulting in higher performance. What-if analyses bring out effects of modifying other structural elements. In conclusion, we claim that the information feedback based methodology is general enough to be useful in designing decision support systems for capacity augmentation. The limitations of the model are also discussed and possible extensions identified. 相似文献
5.
An energy-dependent partitioning scheme is explored for extracting a small number of eigenvalues of a real symmetric matrix with the help of genetic algorithm. The proposed method is tested with matrices of different sizes (30 × 30 to 1000 × 1000). Comparison is made with Löwdin’s strategy for solving the problem. The relative advantages and disadvantages of the GA-based method are analyzed 相似文献
6.
Raj Gandhi Kamales Kar S. Uma Sankar Abhijit Bandyopadhyay Rahul Basu Pijushpani Bhattacharjee Biswajoy Brahmachari Debrupa Chakraborti M. Chaudhury J. Chaudhury Sandhya Choubey E. J. Chun Atri Desmukhya Anindya Datta Gautam Dutta Sukanta Dutta Anjan Giri Sourendu Gupta Srubabati Goswami Namit Mahajan H. S. Mani A. Mukherjee Biswarup Mukhopadhyaya S. N. Nayak M. Randhawa Subhendu Rakshit Asim K. Ray Amitava Raychaudhuri D. P. Roy Probir Roy Suryadeep Roy Shiv Sethi G. Sigl Arunansu Sil N. Nimai Singh Mark Vagins Urjit Yagnik 《Pramana》2003,60(2):405-409
This is the report of neutrino and astroparticle physics working group at WHEPP-7. Discussions and work on CP violation in
long baseline neutrino experiments, ultra high energy neutrinos, supernova neutrinos and water Cerenkov detectors are discussed. 相似文献
7.
The results of the electronic structures and conduction properties of four novel donor-acceptor polymers based on polysilole, obtained on the basis of ab initio Hartree-Fock crystal orbital method using their optimized geometries, are reported. The repeat unit of these polymers consists of bicyclopentadisilole unit bridged by an electron-accepting group Y(Y=CCH2 in PSICH, CO in PSICF, CCF2 and CC(CN)2 in PSICN). All the polymers on the basis of their geometries and π-bond order values are found to have benzenoid-type electronic structures. Comparison of the important electronic properties such as ionization potential, electron affinity and band-gap of these polymers indicates PSICN to be the best candidate for intrinsic conductivity and reductive (n-) doping while PSICH is predicted to be the best candidate for oxidative (p-) doping. All these polymers are estimated to have band-gap values ranging between 1 and 2 eV. The low band-gap values of these polymers are rationalised on the basis of the patterns of their frontier orbitals. 相似文献
8.
Insertion of CS(2) into the Ru-H bond of cis-[(dppe)(2)Ru(H)(2)] takes place to afford the hydride dithioformate complex trans-[(dppe)(2)Ru(H)(SC(S)H)]. The hydride dithioformate complex reacts under very mild conditions with MeX (X = OTf, I) to give the hydride methyldithioformate derivative trans-[(dppe)(2)Ru(H)(SC(SMe)H)][X]. Three different pathways have been found to cleave off the ester moiety from the metal complex. A method to recover the ruthenium starting material upon elimination of the methyldithioformate is presented. This is a novel case of C(1) chemistry using carbon disulfide. 相似文献
9.
Addition of excess carbon disulfide to cis/trans-[(dppm)(2)Ru(H)(2)] results in the methanedithiolate complex [(dppm)(2)Ru(eta(2)-S(2)CH(2))] 4 via the intermediacy of cis-[(dppm)(2)Ru(H)(SC(S)H)] 2. The X-ray crystal structure of this species has been determined. 相似文献
10.
Sutka RL Ostrom NE Ostrom PH Gandhi H Breznak JA 《Rapid communications in mass spectrometry : RCM》2003,17(7):738-745
The relative importance of individual microbial pathways in nitrous oxide (N(2)O) production is not well known. The intramolecular distribution of (15)N in N(2)O provides a basis for distinguishing biological pathways. Concentrated cell suspensions of Methylococcus capsulatus Bath and Nitrosomonas europaea were used to investigate the site preference of N(2)O by microbial processes during nitrification. The average site preference of N(2)O formed during hydroxylamine oxidation by M. capsulatus Bath (5.5 +/- 3.5 per thousand) and N. europaea (-2.3 +/- 1.9 per thousand) and nitrite reduction by N. europaea (-8.3 +/- 3.6 per thousand) differed significantly (ANOVA, f((2,35)) = 247.9, p = 0). These results demonstrate that the mechanisms for hydroxylamine oxidation are distinct in M. capsulatus Bath and N. europaea. The average delta(18)O-N(2)O values of N(2)O formed during hydroxylamine oxidation for M. capsulatus Bath (53.1 +/- 2.9 per thousand) and N. europaea (-23.4 +/- 7.2 per thousand) and nitrite reduction by N. europaea (4.6 +/- 1.4 per thousand) were significantly different (ANOVA, f((2,35)) = 279.98, p = 0). Although the nitrogen isotope value of the substrate, hydroxylamine, was similar in both cultures, the observed fractionation (delta(15)N) associated with N(2)O production via hydroxylamine oxidation by M. capsulatus Bath and N. europaea (-2.3 and 26.0 per thousand, respectively) provided evidence that differences in isotopic fractionation were associated with these two organisms. The site preferences in this study are the first measured values for isolated microbial processes. The differences in site preference are significant and indicate that isotopomers provide a basis for apportioning biological processes producing N(2)O. 相似文献