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21.
Seong Ik Yoo Tae Yeon Lee Jin‐San Yoon Ik‐Mo Lee Mal‐Nam Kim Han Sup Lee 《应用聚合物科学杂志》2002,83(4):767-776
The interfacial reaction of the polyethylene (PE)/starch blend system containing the reactive compatibilizer maleated polyethylene (m‐PE) was directly characterized by Fourier transform infrared (FTIR) spectroscopy. A significant amount of anhydride groups on m‐PE existed as hydrolyzed forms, resulting in a large amount of carboxyl groups. Using a vacuum‐heating‐cell designed in the laboratory, the carboxyl groups were successfully transformed into the dehydrolyzed state (i.e., anhydride group). This result enabled the direct spectroscopic observation of chemical reaction occurring at the interface. For the PE/starch blend system containing m‐PE, the chemical reaction at the interface was verified by the evolution of ester and carboxyl groups in the FTIR spectra. The effect of the reactive compatibilizer on the interfacial morphology was also examined by scanning electron micrography (SEM). Enhanced interfacial adhesion was clearly observed for the blend system containing reactive compatibilizer. Tensile strengths of blend systems containing m‐PE also increased noticeably compared with the corresponding system without compatibilizer. A similar observation was made for the breaking elongation data. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 767–776, 2002 相似文献
22.
Shirshova E. P. Mal’tseva A. L. Astashkina O. V. Lysenko A. A. Fomenko Yu. A. 《Fibre Chemistry》2021,53(3):189-193
Fibre Chemistry - The article is devoted to the development of two-layer composites with a fluoroplastic matrix and fiberglass reinforcing elements. The fluoroplastic matrix acts as a protective... 相似文献
23.
Kazantsev Yu. N. Kraftmakher G. A. Mal’tsev V. P. Solosin V. S. 《Journal of Communications Technology and Electronics》2022,67(8):930-937
Journal of Communications Technology and Electronics - The characteristics of an artificial magnetic conductor (AMC) based on an anisotropic composite material consisting of capacitive gratings... 相似文献
24.
Jani Das Ajit Paul Abraham Prakash C. Ghosh Rangan Banerjee 《Clean Technologies and Environmental Policy》2018,20(1):65-80
Electricity supply in India is from a centralized grid. Many parts of the country experience grid interruptions. Life cycle energy and environmental analysis has been done for a 27 kWp photovoltaic system which acts as grid backup for 3 h outage in an Indian urban residential scenario. This paper discusses energy requirements and carbon emission for a PV storage system for five different battery technologies in Indian context. This can be used as a metric for comparative analysis for new batteries, with an undeveloped market. The energy requirements for the components are quantified and are compared in terms of energy payback time (EPBT) and Net Energy Ratio (NER). All the calculations are done for Indian context. EPBT is found to be in the range of 2–4.5 years for all the systems, while NER is in the range of 6.6–2.52. NaS has the highest emission factor of 0.67 kgCO2/kWh and the least for NiCd (0.091 kgCO2/kWh). These factors can be used to select a PV battery option and to target selection of materials and systems based on the reported values. 相似文献
25.
Ajit Kumar MahapatraAuthor Vitae Giridhari HazraAuthor VitaeNirmal Kumar DasAuthor Vitae Shyamaprosad GoswamiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):456-462
A new triphenylamine-based fluorogenic probe bearing an indolylmethane unit (R1) was developed as a fluorescent chemosensor with high selectivity toward Cu2+ over other cations tested. The new probe R1 only sensed Cu2+ among heavy and transition metal (HTM) ions in CH3CN/H2O (70/30, v/v) solution. The capture of Cu2+ by the receptor resulted in deprotonation of the secondary amine conjugated to the triphenylamine, so that the electron-donation ability of the “N” atom would be greatly enhanced; thus sensor showed a 250 nm change in the new absorption band (from 291 nm to 541 nm) and a large colorimetric response, it also exhibited the large decrease in fluorescence intensity at 378 nm and affinity to Cu2+ over other cations such as Hg2+, Fe3+, Pb2+, Zn2+, Cd2+, Ni2+, Co2+ and Mn2+ make this compound a useful chemosensor for Cu2+ detection in CH3CN/H2O (70/30, v/v) mixture. The probe R1 (c = 1.0 × 10−6 M) displayed significant fluorescence change and colorimetric change upon addition of Cu2+ among the metal ions examined. 相似文献
26.
Mursalin Akon Towhidul Islam Xuemin Shen Ajit Singh 《Peer-to-Peer Networking and Applications》2010,3(2):83-99
In this paper, we introduce Systematic P2P Aided Cache Enhancement or SPACE, a new collaboration scheme among clients in a computer cluster of a high performance computing facility to share their caches
with each other. The collaboration is achieved in a distributed manner, and is designed based on peer-to-peer computing model.
The objective is to provide (1) a decentralized solution, and (2) a near optimal performance with reasonably low overhead.
Simulation results are given to demonstrate the performance of the proposed scheme. In addition, the results show that SPACE
evenly distributes work loads among participators, and entirely eliminates any requirement of a central cache manager. 相似文献
27.
Diane de Zlicourt Liang Ge Chang Wang Fotis Sotiropoulos Anvar Gilmanov Ajit Yoganathan 《Computers & Fluids》2009,38(9):1749-1762
Image guided computational fluid dynamics is attracting increasing attention as a tool for refining in vivo flow measurements or predicting the outcome of different surgical scenarios. Sharp interface Cartesian/Immersed-Boundary methods constitute an attractive option for handling complex in vivo geometries but their capability to carry out fine-mesh simulations in the branching, multi-vessel configurations typically encountered in cardiovascular anatomies or pulmonary airways has yet to be demonstrated. A major computational challenge stems from the fact that when such a complex geometry is immersed in a rectangular Cartesian box the excessively large number of grid nodes in the exterior of the flow domain imposes an unnecessary burden on both memory and computational overhead of the Cartesian solver without enhancing the numerical resolution in the region of interest. For many anatomies, this added burden could be large enough to render comprehensive mesh refinement studies impossible. To remedy this situation, we recast the original structured Cartesian formulation of Gilmanov and Sotiropoulos [Gilmanov A, Sotiropoulos F. A hybrid Cartesian/immersed boundary method for simulating flows with 3D, geometrically complex, moving bodies. J Comput Phys 2005;207(2):457–92] into an unstructured Cartesian grid layout. This simple yet powerful approach retains the simplicity and computational efficiency of a Cartesian grid solver, while drastically reducing its memory footprint. The method is applied to carry out systematic mesh refinement studies for several internal flow problems ranging in complexity from flow in a 90° pipe bend to flow in an actual, patient-specific anatomy reconstructed from magnetic resonance images. Finally, we tackle the challenging clinical scenario of a single-ventricle patient with severe arterio-venous malformations, seeking to provide a fluid dynamics prospective on a clinical problem and suggestions for procedure improvements. Results from these simulations demonstrate very complex cardiovascular flow dynamics and underscore the need for high-resolution simulations prior to drawing any clinical recommendations. 相似文献
28.
Soumya Priyadarsini Panda Ajit Kumar Nayak 《International Journal of Speech Technology》2017,20(4):959-976
Designing text-to-speech systems capable of producing natural sounding speech segments in different Indian languages is a challenging and ongoing problem. Due to the large number of possible pronunciations in different Indian languages, a number of speech segments are needed to be stored in the speech database while a concatenative speech synthesis technique is used to achieve highly natural speech segments. However, the large speech database size makes it unusable for small hand held devices or human computer interactive systems with limited storage resources. In this paper, we proposed a fraction-based waveform concatenation technique to produce intelligible speech segments from a small footprint speech database. The results of all the experiments performed shows the effectiveness of the proposed technique in producing intelligible speech segments in different Indian languages even with very less storage and computation overhead compared to the existing syllable-based technique. 相似文献
29.
S. V. Antonenko O. S. Malinovskaya S. N. Mal’tsev 《Instruments and Experimental Techniques》2007,50(4):543-544
A new method for manufacturing multiwall carbon nanotubes by the current annealing in vacuum of the graphite paper saturated with Ni, Co, and Fe catalysts is designed. By using a scanning tunnel microscope, structural characteristics of the modified graphite paper are studied. Y- and V-shaped nanotubes are found. 相似文献
30.
A small single-cylinder diesel engine is used to thermally age model (Pt + Rh/Ba/γ-Al2O3) lean NOx traps (LNTs) under lean/rich cycling at target temperatures of 600 °C, 700 °C, and 800 °C. During an aging cycle, fuel is injected into the exhaust to achieve reproducible exotherms under lean and rich conditions with the average temperature approximating the target temperature. Aging is performed until the cycle-average NOx conversion measured at 400 °C is approximately constant. Engine-based NOx conversion decreased by 42% after 60 cycles at 600 °C, 36% after 76 cycles at 700 °C and 57% after 46 cycles at 800 °C. The catalyst samples were removed and characterized by XRD and using a microreactor that allowed controlled measurements of surface area, precious metal size, NOx storage, and reaction rates. Three aging mechanisms responsible for the deactivation of LNTs have been identified: (i) loss of dispersion of the precious metals, (ii) phase transitions in the washcoat materials, and (iii) loss of surface area of the storage component and support. These three mechanisms are accelerated when the aging temperature exceeds 850 °C—the γ to δ transition temperature of Al2O3. Normalization of rates of NO reacted at 400 °C to total surface area demonstrates the biggest impact on performance stems from surface area losses rather than from precious metal sintering. 相似文献