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排序方式: 共有940条查询结果,搜索用时 15 毫秒
931.
Fast depletion of fossil fuels is demanding an urgent need to carry out research work to find out the viable alternative fuels for meeting sustainable energy demand with minimum environmental impact. In the future, our energy systems will need to be renewable and sustainable, efficient and cost-effective, convenient and safe. The technology for producing hydrogen from a variety of resources, including renewable, is evolving and that will make hydrogen energy system as cost-effective. Hydrogen safety concerns are not the cause for fear but they simply are different than those we are accustomed to with gasoline, diesel and other fossil fuels. For the time being full substitution of diesel with hydrogen is not convenient but use of hydrogen in a diesel engine in dual fuel mode is possible. So Hydrogen has been proposed as the perfect fuel for this future energy system. The experiment is conducted using diesel–hydrogen blend. A timed manifold induction system which is electronically controlled has been developed to deliver hydrogen on to the intake manifold. The solenoid valve is activated by the new technique of taking signal from the rocker arm of the engine instead of cam actuation mechanism. In the present investigation hydrogen-enriched air has been used in a diesel engine with hydrogen flow rate at 0.15 kg/h. As diesel is substituted and hydrogen is inducted, the NOx emission is increased. In order to reduce NOx emission an EGR system has been developed. In the EGR system a lightweight EGR cooler has been used instead of bulky heat exchanger. In this experiment performance parameters such as brake thermal efficiency, volumetric efficiency, BSEC are determined and emissions such as oxides of nitrogen, carbon dioxide, carbon monoxide, hydrocarbon, smoke and exhaust gas temperature are measured. Dual fuel operation with hydrogen induction coupled with exhaust gas recirculation results in lowered emission level and improved performance level compared to the case of neat diesel operation. 相似文献
932.
933.
A simple and straightforward derivation of the eigenvectors of the DFT matrix is given. The multiplicity of each of the four eigenvalues of a two-dimensional DFT matrix is then supplied in closed form that is generalizable to higher dimensions. 相似文献
934.
Stephen Manova Lazarus Godson Asirvatham Rajesh Nimmagadda Jefferson Raja Bose Somchai Wongwises 《亚洲传热研究》2020,49(8):4834-4856
The feasibility of using multiport minichannel (MPMC) as thermosyphon for cooling miniaturized electronic products is experimentally investigated with acetone as the working fluid. A detailed analysis on thermal performance and entropy generation due to heat transfer and pressure drop with the effects of heat load (10-50 W), filling ratio (FR; 40%, 50%, and 60%), and inclination angle (45°, 60°, and 90°) has been carried out. The results showed a reduction of 22.2% and 9.31% in thermal resistance and evaporator wall temperature at optimum filling ratio (OFR) of 50%. Reduction in entropy generation due to heat transfer and pressure drop of 16.6% and 12.3%, respectively, was observed at OFR. Internal fins in MPMC increase the surface area and evaporation rate by enhancing heat transfer leading to a decrease in the rate of entropy generation. Multiport increases surface tension of condensate at right angles to the flow direction along with the effects of gravity and enhancing rate of condensation. A new correlation is developed to predict evaporator wall temperature as a function of heat load and FR. The proposed correlation agrees well with a deviation of ±20% with present experimental results and also with the published literature. Thus, the obtained results will be useful in cooling miniaturized electronic devices. 相似文献
935.
Ria Ghosh Soumendra Singh Dipanjan Mukherjee Susmita Mondal Monojit Das Uttam Pal Aniruddha Adhikari Aman Bhushan Surajit Bose Siddharth Sankar Bhattacharyya Debasish Pal Tanusri Saha-Dasgupta Maitree Bhattacharyya Debasis Bhattacharyya Asim Kumar Mallick Ranjan Das Samir Kumar Pal 《Chembiochem : a European journal of chemical biology》2022,23(9):e202200109
Drug delivery to a target without adverse effects is one of the major criteria for clinical use. Herein, we have made an attempt to explore the delivery efficacy of SDS surfactant in a monomer and micellar stage during the delivery of the model drug, Toluidine Blue (TB) from the micellar cavity to DNA. Molecular recognition of pre-micellar SDS encapsulated TB with DNA occurs at a rate constant of k1 ∼652 s−1. However, no significant release of encapsulated TB at micellar concentration was observed within the experimental time frame. This originated from the higher binding affinity of TB towards the nano-cavity of SDS at micellar concentration which does not allow the delivery of TB from the nano-cavity of SDS micelles to DNA. Thus, molecular recognition controls the extent of DNA recognition by TB which in turn modulates the rate of delivery of TB from SDS in a concentration-dependent manner. 相似文献
936.
Bidhan Das Debabrata Chakrabarty Avik Mukherjee Chandan Guha Saswata Bose 《Polymer Engineering and Science》2023,63(2):546-561
This study encompasses the characterization of corona-treated milky white co-extruded polyethylene films. The surface energies developed at various applied voltages were investigated by standard wetting (dyne) solutions of binary liquid mixtures. A maximum treatment of 40 dynes/cm was achieved at 3.0 kW of the applied load. Maximum heat seal joint strength of 1.05 kN/m was achieved only when an untreated/untreated surface combination was sealed, while a treated/treated surface combination exhibited the minimum heat seal joint strength of 0.98 kN/m. Standard Scotch tape method was employed for testing peel adhesion. An applied load of more than 3.0 kW shows a decreasing trend in surface energy. The coefficient of friction on the treated surface was also investigated. Aging under different environmental conditions had hardly any impact on the treatment levels within the time period under study. A sufficiently opaque (Opacity—99%) white film at Titanium dioxide (TiO2) loading of 7.5% resulted in a very good barrier film. 相似文献
937.
938.
Babitha Selvananthan Omar Aziz Arvind D. Lee Keagan Werner-Gibbings Bhadran Bose Kamal Sud 《Hemodialysis international. International Symposium on Home Hemodialysis》2023,27(2):E19-E22
Blood leak alarms are increasingly rare and may be triggered by rupture of the dialyzer membrane, or intravascular hemolysis. We report two patients who developed hemolysis following Angiojet™ thrombolysis and thrombectomy of thrombosed arteriovenous fistulas, triggering blood leak alarms on hemodialysis, the occurrence of which has not been reported before. AngioJet™-induced hemolysis should be considered in the differential diagnosis for blood leak alarms occurring soon after an intervention on an arterio-venous (AV) fistula. 相似文献
939.
Das Rahul Chattopadhyay Ankush Chanda Manash Sarkar Chandan K. Bose Chayanika 《SILICON》2022,14(15):9417-9430
Silicon - In this paper, analytical modeling of a Dielectric Modulated Double Gate Field Effect Transistor (DM-DGFET) for biosensing application is presented with extensive data analysis. Firstly,... 相似文献
940.
Rajiva Lochan Mohanty Sumanta Chaudhuri Paromita Chakraborty Vijay Kumar Mishra Kunja Bihari Sahu Bitanjaya Das 《亚洲传热研究》2023,52(7):4711-4731
Investigations are conducted on electromagnetohydrodynamic (EMHD) flow and heat transfer in a third-grade fluid flowing through large parallel plates, which are maintained at constant temperatures. The impact of convective heat transmission is disregarded since the space between the plates is small. The influence of viscous dissipation is considered. Despite being addressed for Newtonian fluids, the conduction problem with the viscous dissipation effect is not examined in third-grade fluids for EMHD flow and heat transfer behavior. The least-square method is adopted to solve nondimensional, nonlinear momentum and energy conservation equations to get the dimensionless velocity, temperature distribution, and heat flux. Temperature and heat flux are investigated in relation to the third-grade fluid parameter, the Hartmann number, the electric field parameter, and the Brinkman number. The findings show a rise in the Brinkman number dramatically increases heat transfer from both walls, necessitating cooling of both plates. The heat flow from both walls increases as the parameters of third-grade fluid increases. 相似文献