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31.
A novel ICT project in rural India uses long-distance Wi-Fi networking to enable high-quality videoconferencing between eye hospitals and remote village clinics. The project highlights the importance of sustainability as a first-class goal for systems research. 相似文献
32.
Ru(II)–CO complexes of thioarylazoimidazoles: Syntheses,structures, spectroscopy and DFT calculation
T.K. Mondal P. Raghavaiah A.K. Patra C. Sinha 《Inorganic chemistry communications》2010,13(2):273-277
The complexes, cis-(CO)-trans-(Cl)-[Ru(SRaaiNR)(CO)2Cl2] (2) and trans-(Cl)-[Ru(SRaaiNR)(CO)Cl2] (3) (SRaaiNR = 1-alkyl-2-{(o-thioalkyl)phenylazo}imidazoles; R = Me (1a) and Et (1b)) have been synthesized and characterized. The structural confirmation is achieved by single crystal X-ray structure determinations. The complexes show Ru(III)/Ru(II) couple and ligand reductions. Electronic structure and spectral properties of the complexes have been explained with the DFT and TDDFT calculation. 相似文献
33.
Ashish Chakraborty Ravi Gunupuru Debdeep Maity Subrata Patra E. Suresh Parimal Paul 《Inorganic chemistry communications》2010,13(12):1522-1526
A family of fluoroionophores have been synthesized incorporating Ru(II)-bipyridine moiety as fluorogenic unit and amino/benzenesulphonamido functionalized 1,10-phenanthroline moiety, attached to Ru(II), as binding sites. Two of the ligands and one of the complexes have been characterized crystallographically. Anion recognition property, studied by luminescence, UV–vis and 1H NMR spectroscopy, with a large number of anions exhibit strong complexation with F?, H2PO4? and AcO?. Binding constants have been determined from luminescence titration and 1H NMR study gave insight about binding site of anions. Bidentate chelating nature of the H2PO4? and AcO? anions and steric crowding created by benzenesulphonamide moiety has significantly influenced binding constants and selectivity. 相似文献
34.
35.
H. A. Lanjewar Pranavkumar Tripathi M. Singhai P. K. Patra 《Journal of Materials Engineering and Performance》2014,23(10):3600-3609
Hot ductility studies have been performed on C-Mn and C-Mn-Nb steels with an approach to simulate the effect of cooling conditions experienced by steel in secondary cooling zone during continuous casting. Thermal oscillations prior to tensile straining deteriorate hot ductility of steel by deepening and widening the hot ductility trough. C-Mn steels are found to exhibit ductility troughs in three distinct zones whereas C-Mn-Nb steel shows drop in ductility only at low temperature in the vicinity of ferrite transformation temperatures. Start of ferrite transformation in steels causes yield ratio to increase while work hardening rates and strength coefficient decrease with decrease in test temperature in presence of thermal oscillation prior to tensile testing. Inhibition of recrystallization due to build-up of AlN particles along with the presence of MnS particles in structure and low work hardening rates causes embrittlement of steel in austenitic range. Alloying elements enhancing work hardening rates in austenitic range can be promoted to improve hot ductility. The presence of low melting phase saturated with impurities along the austenitic grain boundaries causes intergranular fracture at high temperature in C-Mn steels. 相似文献
36.
Amlan K Patra 《Journal of the science of food and agriculture》2010,90(15):2700-2708
BACKGROUND: A meta‐analysis study was conducted to investigate the changes in rumen fermentation characteristics when methane inhibition by phytochemicals is employed. The whole database containing 185 treatment means from 36 published studies was divided into four subsets according to the major phytochemicals used in the studies, i.e. saponins, tannins, essential oils (EO) and organosulfur compounds (OS). RESULTS: Changes in protozoal numbers showed linear relationships with changes in methane production by saponins (R2 = 0.48), tannins (R2 = 0.30) and EO (R2 = 0.20) but not OS. Concentrations of total volatile fatty acids (VFA) and acetate did not show any relationship (P > 0.1) with changes in methane due to saponins. However, propionate production increased linearly with increasing inhibition of methane (R2 = 0.31), which resulted in a linear (R2 = 0.26) decrease in acetate/propionate ratio (A/P) with decreasing methane production. Concentrations of total VFA, acetate and propionate did not change with changes in methane production by tannins. However, A/P showed a significant linear relationship (R2 = 0.27) with decreasing methane formation. Concentrations of total VFA (R2 = 0.44) and propionate (R2 = 0.15) changed linearly and positively with changes in methane production by EO. However, acetate production (R2 = 0.22) and A/P (R2 = 0.17) increased linearly with increasing inhibition of methane by EO. Changes in concentrations of total VFA (R2 = 0.60) and acetate (R2 = 0.35) decreased linearly while those of propionate increased linearly (R2 = 0.23) with increasing inhibition of methane by OS. Consequently, A/P decreased linearly (R2 = 0.30) with decreasing methane production by OS. Digestibilities of organic matter (OM) and neutral detergent fibre were not affected by inhibition of methane production by saponins, EO and OS, but digestibility of OM decreased with decreasing methane production by tannins. CONCLUSION: The inhibition of methane production by phytochemicals results in changes in rumen fermentation that differ depending on the types of phytochemicals. Copyright © 2010 Society of Chemical Industry 相似文献
37.
A novel DCT domain CRT-based watermarking scheme for image authentication surviving JPEG compression
Digital watermarking techniques have been proposed for copyright protection and authentication of multimedia data. In this paper, we propose a novel Chinese Remainder Theorem (CRT)-based technique for digital watermarking in the Discrete Cosine Transform (DCT) domain that is robust to several common attacks. We compared the performance of the proposed technique with recently proposed Singular Value Decomposition (SVD)-based and spatial CRT-based watermarking schemes. Experimental results have shown that the proposed technique successfully makes the watermark perceptually invisible and has better robustness to common image manipulation techniques such as JPEG compression, brightening and sharpening effects compared to the spatial domain-based CRT scheme. The proposed scheme is able to achieve a Tamper Assessment Function (TAF) value of less than 10% when the watermarked image undergoes JPEG compression between a range of 50 to 70%, where as, the spatial CRT-based scheme produce TAF value of more than 35% and the SVD-based scheme produces TAF value between 10 to 40% depending on the host image, for the same range of compression. When the watermark capacity is doubled, the proposed technique is still able to maintain imperceptibility and low TAF values, for most of the attacks. 相似文献
38.
This paper presents a simple method for evaluating the reliability of a multistate flow network. A system is considered reliable only if it successfully transmits at least the required system capacity from the transmitter to the receiver station. All successful states are obtained from the knowledge of the max-flow min-cuts of the system graph. Examples are solved to demonstrate the applicability of proposed method. It is observed that the method is simple, computationally fast and efficient. 相似文献
39.
Kim S. Bey Abani Patra J. Tinsley Oden 《International journal for numerical methods in engineering》1995,38(22):3889-3908
This paper describes a parallel algorithm based on discontinuous hp-finite element approximations of linear, scalar, hyperbolic conservation laws. The paper focuses on the development of an effective parallel adaptive strategy for such problems. Numerical experiments suggest that these techniques are highly parallelizable and exponentially convergent, thereby yielding efficiency many times superior to conventional schemes for hyperbolic problems. 相似文献
40.
Jayaprakash Behera Swapnita Patra Shaikh Nazrul Satendra Kumar Sharma Deepak Kumar Mahendra Kumar Verma Anil Kumar Katare Sarat K. Swain 《应用聚合物科学杂志》2024,141(16):e55246
Herein, nano boron nitride (BN) laminated poly(ethyl methacrylate) (PEMA)/poly(vinyl alcohol) (PVA) nanocomposite films are fabricated by using a simple in situ polymerization technique with incorporation of silver nanoparticles (Ag NPs). Structural investigations of PEMA/PVA/Ag@BN nanocomposite thin films are carried out by Fourier-transform infrared spectroscopy, dynamic light scattering, X-ray diffraction analysis, 1H nuclear magnetic resonance, 13C nuclear magnetic resonance, and mass spectrometry. The change in morphology of PEMA/PVA matrix due to the reinforcement of BN platelets are identified by electron microscopic studies. The unique tortuous paths are achieved by the dispersion of BN platelets by which gas penetration is restricted with enhancing the barrier properties of the material by 6.5 folds at 5 wt% BN content as compared with neat PEMA/PVA. Acid and alkali resistant along with biodegradability behavior of as-synthesized nanocomposites are studied. From limiting oxygen index (LOI) results, it is found that the prepared materials are fire retardant in nature owing to effective reinforcement of BN layers. Antibacterial activities of PEMA/PVA/Ag@BN nanocomposite are studied by Xanthomonas citri or axonopodis pv. Citri, Escherichia coli, and Xanthomonas oryzae pv. Oryzae because of Ag NPs reinforcement. The substantial improvements in gas barrier, fire retardant, and antibacterial properties enable the materials for packaging application. 相似文献