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21.
A crying need of the day in India is to supply safe drinking water to its villages, towns and cities. Though the urban needs are partially met by organized water supply schemes, acute water shortages are felt at various times in this sector also with the expanding industrialization of the country. In many areas of arid and semi-arid regions, only brackish waters are available which are unfit for human consumption.Research and development effort at CSMCRI on the two membrane processes, reverse osmosis and electrodialysis, during the past decade has been reviewed. Some of the current activities in the rural sector and the future potential for these two processes in tackling the pressing needs of potable water to the rural masses in India are outlined. In the industrial sector, these two processes have immense potentialities in pollution abatement and water reuse.  相似文献   
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The computation of a six-dimensional density matrix is the crucial step for the evaluation of kinetic energy in electronic structure calculations. For molecules with heavy nuclei, one has to consider a very refined mesh in order to deal with the nuclear cusps. This leads to high computational time and needs huge memory for the computation of the density matrix. To reduce the computational complexity and avoid discretization errors in the approximation, we use mesh-free canonical tensor products in electronic structure calculations. In this paper, we approximate the six-dimensional density matrix in an efficient way and then compute the kinetic energy. Accuracy is examined by comparing our computed kinetic energy with the exact computation of the kinetic energy.  相似文献   
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Journal of Electronic Testing - Error-Tolerant applications regularly accomplish more data adaption. Approximate computing is one of the optimum strategies for data manipulation in several...  相似文献   
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Developing light weight polymer based composites dispersed with novel reinforcements which can function well in the presence of aggressive environments is an active research field in the materials engineering. Hence, in the current work, halloysite nanotubes (1 %, 2 %, 4 %, 6 %, 8 % and 10 % by weight) were reinforced into acrylonitrile butadiene styrene/polycarbonate blend and the role of reinforcing phases on the mechanical performance under aggressive environmental conditions has been evaluated. Hardness was measured as gradually increased in the composites with the increased content of the reinforcements. Impact strength of the composites was observed as increased in the composites up to 4 % reinforcement and further decreased. Increased strength was measured for the composite up to 2 % reinforcement. Ductility of the composites was decreased as reflected form the decreased % of elongation with the higher fraction of reinforcements due to induced brittleness. The composites were exposed to diluted sulfuric acid for 3 h and 6 h at 60 °C and then subjected to tensile loading. With the increased time of exposure, composites with 1 % and 2 % reinforcement exhibited relatively better performance.  相似文献   
28.
Defense frontier analysis of quantum cryptographic systems   总被引:1,自引:0,他引:1  
Slutsky B  Rao R  Sun PC  Tancevski L  Fainman S 《Applied optics》1998,37(14):2869-2878
When a quantum cryptographic system operates in the presence of background noise, security of the key can be recovered by a procedure called key distillation. A key-distillation scheme effective against so-called individual (bitwise-independent) eavesdropping attacks involves sacrifice of some of the data through privacy amplification. We derive the amount of data sacrifice sufficient to defend against individual eavesdropping attacks in both BB84 and B92 protocols and show in what sense the communication becomes secure as a result. We also compare the secrecy capacity of various quantum cryptosystems, taking into account data sacrifice during key distillation, and conclude that the BB84 protocol may offer better performance characteristics than the B92.  相似文献   
29.
Critical current densities of the superconducting Y-Ba-Cu-O (YBCO) films have been observed to decrease with the increase of power of microwave radiation. Presence of Josephson type of junctions in the microbridges has been established from the microwave irradiation and magnetic field studies. BCS energy gap parameter (2/kT c ) has been calculated from thedI/dV characteristics and found to be 3.7 at 13 K.  相似文献   
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