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161.
Summary An efficient, reproducible and rapid gas chromatographic method for the analysis of nitrochlorobenzenes has been described
in this paper. The method uses FFAP as stationary phase and 3,4-dichloronitrobenzene as internal standard. The total analysis
time of the method is less than 15 minutes with a coefficient of variation ranging from 0.41% to 1.19% for different levels
of three isomers. 相似文献
162.
Audrey Yoke Yee Ho Emma Luong Van Chee Tiong Lim Sriram Natarajan Noha Elmouelhi Hong Yee Low Murty Vyakarnam Kevin Cooper Isabel Rodriguez 《Journal of Polymer Science.Polymer Physics》2014,52(8):603-609
The super hydrophobic, self‐cleaning properties of natural species derive from the fine hierarchical topography evolved on their surfaces. Hierarchical architectures which are function‐mimetic of the lotus leaf are here described and created from multi‐scale hierarchical assembled templates. The first level of hierarchy was a micromachined dome structure template and the second level of hierarchy was added by layering a thin nanoporous membrane such as porous anodized alumina or an ion track etch membrane. The assembled templates were nanoimprinted by a single step process on thermoplastic films. The wetting angle of the surfaces reached a value of 160° and the self‐cleaning behavior was observed. The superhydrophobic behavior remained over 1 year after fabrication, which demonstrates the stability of these polymeric self‐cleaning topographies. © 2014 Wiley Periodicals, Inc. J. Polym. Sci. Part B. Polym. Phys. 2014 , 52, 603–609 相似文献
163.
Erratum for paper “Theory of extreme correlations using canonical Fermions and path integrals”, B.S. Shastry, Ann. Phys. 343, 164–199 (2014) http://dx.doi.org/10.1016/j.aop.2014.02.005 AOP69618. 相似文献
164.
Diallyltin dibromide reacts with β-keto-aldehydes possessing no aromatic side groups and with (hydroxy) aryl imines to afford the expected homoallyl alcohols or amines respectively. With β-ketoaldehydes having aromatic side groups, skipped or conjugated dienes are obtained depending on whether or not an aqueous work up procedure is used. 相似文献
165.
G. Mugunthan Dharmarajan Sriram Perumal Yogeeswari K. P. Ravindranathan Kartha 《Journal of carbohydrate chemistry》2013,32(7):553-570
O-Galactopyranosides were synthesized as potential mimics of uridine 5c-diphosphate galactopyranose (UDP-Galp), which is the substrate of the mutase enzyme involved in the mycobacterial cell wall biosynthesis by converting UDP-Galp to UDP-Galf. In vitro assay against the Mycobacterium tuberculosis H37Rv strain gave promising results with minimum inhibitory concentration (MIC) values in the range of 3.13 to 25 μg/mL. 相似文献
166.
Rajinder Kumar Sriram S. Nivarthi H. Ted Davis D.M. Kroll Robert S. Maier 《国际流体数值方法杂志》1999,31(5):801-819
The lattice‐Boltzmann (LB) method, derived from lattice gas automata, is a relatively new technique for studying transport problems. The LB method is investigated for its accuracy to study fluid dynamics and dispersion problems. Two problems of relevance to flow and dispersion in porous media are addressed: (i) Poiseuille flow between parallel plates (which is analogous to flow in pore throats in two‐dimensional porous networks), and (ii) flow through an expansion–contraction geometry (which is analogous to flow in pore bodies in two‐dimensional porous networks). The results obtained from the LB simulations are compared with analytical solutions when available, and with solutions obtained from a finite element code (FIDAP) when analytical results are not available. Excellent agreement is found between the LB results and the analytical/FIDAP solutions in most cases, indicating the utility of the lattice‐Boltzmann method for solving fluid dynamics and dispersion problems. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
167.
T.N. Sriram A. Bhattacharya M. González R. Martínez I. del Puerto 《Stochastic Processes and their Applications》2007
Controlled branching processes (CBP) with a random control function provide a useful way to model generation sizes in population dynamics studies, where control on the growth of the population size is necessary at each generation. An important special case of this process is the well known branching process with immigration. Motivated by the work of Wei and Winnicki [C.Z. Wei, J. Winnicki, Estimation of the mean in the branching process with immigration, Ann. Statist. 18 (1990) 1757–1773], we develop a weighted conditional least squares estimator of the offspring mean of the CBP and derive the asymptotic limit distribution of the estimator when the process is subcritical, critical and supercritical. Moreover, we show the strong consistency of this estimator in all the cases. The results obtained here extend those of Wei and Winnicki [C.Z. Wei, J. Winnicki, Estimation of the mean in the branching process with immigration, Ann. Statist. 18 (1990) 1757–1773] for branching processes with immigration and provide a unified limit theory of estimation. 相似文献
168.
169.
Gelatin-methylmethacrylate copolymers were prepared using two initiators, viz. potassium persulphate and ceric ammonium nitrate. Grafting experiments were carried out at 60 and 70° using a short polymerization time (20 min) and a prolonged polymerization time (60 min). The composition of the graft copolymer depended upon the type of initiator and the experimental conditions. The number of grafting sites was small and the molecular weight of the grafted branches was very high. These results could be attributed to the heterogeneity of the system. 相似文献
170.
Fluorine substituted cadmium oxide (Cd n O n?1F) cluster for n = 2–6 of linear, ring and three dimensional structures were studied using B3LYP exchange correlation function with LanL2DZ as basis set. Different isomers were optimized to obtain structural stability and various parameters such as dipole moment, HOMO–LUMO gap, ionization potential, electron affinity, stability factor, binding energy, vibrational studies and optical absorption were studied and reported. The stability of the cluster depends on the binding energy and vibrational intensity. 相似文献