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171.
Truong TN Nayak M Huynh HH Cook T Mahajan P Tran LT Bharath J Jain S Pham HB Boonyasiriwat C Nguyen N Andersen E Kim Y Choe S Choi J Cheatham TE Facelli JC 《Journal of chemical information and modeling》2006,46(3):971-984
With the expansion of the Internet and World Wide Web (or the Web), research environments have changed dramatically. As a result, the need to be able to efficiently and securely access information and resources from remote computer systems is becoming even more critical. This paper describes the development of an extendable integrated Web-accessible simulation environment for computational science and engineering called Computational Science and Engineering Online (CSE-Online; http://cse-online.net). CSE-Online is based on a unique client-server software architecture that can distribute the workload between the client and server computers in such a way as to minimize the communication between the client and server, thus making the environment less-sensitive to network instability. Furthermore, the new software architecture allows the user to access data and resources on one or more remote servers as well as on the computing grid while having the full capability of the Web-services collaborative environment. It can be accessed anytime and anywhere from a Web browser connected to the network by either a wired or wireless connection. It has different modes of operations to support different working environments and styles. CSE-Online is evolving into middleware that can provide a framework for accessing and managing remote data and resources including the computing grid for any domain, not necessarily just within computational science and engineering. 相似文献
172.
We report the influence of catalyst formulation and reaction temperature on the formation of carbon nanotube (CNT) thin films
by the chemical vapour deposition (CVD) method. Thin films of CNTs were grown on Fe-Mo/Al2O3-coated silicon wafer by thermal decomposition of methane at different temperatures ranging from 800 to 1000°C. The electron
microscopic investigations, SEM as well as HRTEM, of the as-grown CNT thin films revealed the growth of uniform multi-walled
CNTs in abundance. The intensity ratio of D-band to G-band and FWHM of G-band through Raman measurements clearly indicated
the dependency of structural defects and crystallinity of CNTs in thin films on the catalyst formulation and CVD growth temperature.
The results suggest that thin films of multi-walled CNTs with negligible amount of defects in the nanotube structure and very
high crystallinity can be obtained by thermal CVD process at 925°C. 相似文献
173.
Basic Theory in Construction of Boolean Functions with Maximum Possible Annihilator Immunity 总被引:9,自引:0,他引:9
So far there is no systematic attempt to construct Boolean functions with maximum annihilator immunity. In this paper we present
a construction keeping in mind the basic theory of annihilator immunity. This construction provides functions with the maximum
possible annihilator immunity and the weight, nonlinearity and algebraic degree of the functions can be properly calculated
under certain cases. The basic construction is that of symmetric Boolean functions and applying linear transformation on the
input variables of these functions, one can get a large class of non-symmetric functions too. Moreover, we also study several
other modifications on the basic symmetric functions to identify interesting non-symmetric functions with maximum annihilator
immunity. In the process we also present an algorithm to compute the Walsh spectra of a symmetric Boolean function with O(n2) time and O(n) space complexity.
We use the term “Annihilator Immunity” instead of “Algebraic Immunity” referred in the recent papers [3–5, 9, 18, 19]. Please
see Remark 1 for the details of this notational change 相似文献
174.
Analytical study for investigating the behaviour of Nd-doped Glass, YAG and GGG under the heat capacity mode of operation 总被引:1,自引:0,他引:1
In this paper, detailed analytical studies on heat capacity operation in Nd-doped glass, YAG and GGG has been reported. The effect of the rising temperature on gain and hence on the output energy/power has been numerically worked out. The studies predicted that several kilowatts of the useful output power can be extracted out from the laser materials under investigation when operated under the heat capacity mode. The studies also revealed that output power levels can be scaled up by increasing the number of disks and by increasing the disk aperture size. The factors limiting the power enhancement are also discussed. The estimated results are in good agreement with the other reported experimental results. 相似文献
175.
Recent interest in the study of stacking faults and non-basal slip in Mg alloys is partly based on the argument that these phenomena positively influence mechanical behaviour. Inspection of the published literature, however, reveals that there is a lack of fundamental information on the mechanisms that govern the formation of stacking faults, especially I1-type stacking faults (I1 faults). Moreover, controversial and sometimes contradictory mechanisms have been proposed concerning the interactions between stacking faults and dislocations. Therefore, we describe a fundamental transmission electron microscope investigation on Mg 2.5 at. % Y (Mg–2.5Y) processed via hot isostatic pressing (HIP) and extrusion at 623 K. In the as-HIPed Mg–2.5Y, many 〈c〉 and 〈a〉 dislocations, together with some 〈c + a〉 dislocations were documented, but no stacking faults were observed. In contrast, in the as-extruded Mg–2.5Y, a relatively high density of stacking faults and some non-basal dislocations were documented. Specifically, there were three different cases for the configurations of observed stacking faults. Case (I): pure I2 faults; Case (II): mixture of I1 faults and non-basal dislocations having 〈c〉 component, together with basal 〈a〉 dislocations; Case (III): mixture of predominant I2 faults and rare I1 faults, together with jog-like dislocation configuration. By comparing the differences in extended defect configurations, we propose three distinct stacking fault formation mechanisms for each case in the context of slip activity and point defect generation during extrusion. Furthermore, we discuss the role of stacking faults on deformation mechanisms in the context of dynamic interactions between stacking faults and non-basal slip. 相似文献
176.
Akshay Kumar Vivek SharmaJasneet Kaur Vikas KumarSuhel Mahajan Naveen KumarSwapandeep Singh Chimni 《Tetrahedron》2014
A highly enantioselective addition of diphenyl phosphite to ketimines derived from isatins has been developed employing bifunctional thiourea-tertiary amine organocatalysts. A variety of isatins derived ketimines react well with diphenyl phosphite in the presence of Cinchona-derived thiourea (epiCDT) to provide biologically important chiral 3-substituted 3-amino-2-oxindoles (3a–l) in good yield (up to 88%) and good enantioselectivity (up to 97% ee). The three-component version of the reaction through a domino aza-Wittig/phospha-Mannich sequence has successfully been explored. 相似文献
177.
Asymmetric reduction of aromatic ketones, with the reagent (1) prepared from borane-methyl sulfide (EMS) and (15, 25)-(+)-2-amino-3-methoxy-1-phenyl-1-propanol (3a) yielded the corresponding alcohols in 30–65% e.e. This reagent (1) is also effective for the asymmetric hydroboration of 2-phenyl-1-alkenes, isoelectronically similar to the aromatic ketones, and yielded the corresponding alcohols in 8–37% e.e. 相似文献
178.
Ulhas S. Mahajan 《合成通讯》2013,43(15):2674-2682
A facile method for direct thiocyanation of activated arenes using iodic acid in combination with ammonium thiocyanate is described. 相似文献
179.
Antibacterial activity of nanoparticles has received significant attention worldwide because of their great physical and chemical stability, excellent magnetic properties, and large lattice constant values. These properties are predominate in the food science for enhancing the overall quality, shelf life, taste, flavor, process-ability, etc., of the food. Nanoparticles exhibit attractive antibacterial activity due to their increased specific surface area leading to enhanced surface reactivity. When nanoparticles are suspended in the biological culture, they encounter various biological interfaces, resulting from the presence of cellular moieties like DNA, proteins, lipids, polysaccharides, etc., which helps antibacterial properties in many ways. This paper reviews different methods used for the synthesis of nanoparticles but is specially focusing on the green synthesis methods owing to its non-toxic nature towards the environment. This review highlights their antibacterial application mainly in the food sector in the form of food-nanosensors, food-packaging, and food-additives. The possible mechanism of nanoparticles for their antibacterial behavior underlying the interaction of nano-particles with bacteria, (i) excessive ROS generation including hydrogen peroxide (H2O2), OH? (hydroxyl radicals), and O?2 2 (peroxide); and (ii) precipitation of nano-particles on the bacterial exterior; which, disrupts the cellular activities, resulting in membranes disturbance. All these phenomena results in the inhibition of bacterial growth. Along with this, their current application and future perspectives in the food sector are also discussed. Nanoparticles help in destroying not only pathogens but also deadly fungi and viruses. Most importantly it is required to focus more on the crop processing and its containment to stop the post-harvesting loss. So, nanoparticles can act as a smart weapon towards the sustainable move. 相似文献
180.
M. M. Aggarwal S. K. Badyal V. S. Bhatia S. Chattopadhyay A. K. Dubey M. R. Dutta Majumdar M. S. Ganti A. Kumar T. K. Nayak S. Mahajan D. P. Mahapatra L. K. Mangotra B. Mohanty S. Pal S. C. Phatak B. V. K. Potukuchi R. Raniwala S. Raniwala N. KRao R. N. Singaraju Bikash Sinha M. D. Trivedi R. J. Veenhof Y. P. Viyogi 《Pramana》2003,60(5):1023-1027
A novel gas-based detector using large arrays of honeycomb cells has been developed and tested for use as a pre-shower photon
multiplicity detector (PMD) for STAR and ALICE experiments. The appropriate cell design was arrived at using GARFIELD simulations.
Prototype chambers with cell dimensions corresponding to STAR and ALICE were fabricated and tested at CERN PS and SPS. The
charged particle detection efficiency and the pre-shower characteristics have been studied using pion and electron beams. 相似文献