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41.
The depletion of fossil fuels and increasing demand leads to research in alternate fuels. The alternate fuels are bio-degradable, renewable and non-toxic. Many types of oils are re-used in biodiesel production, considering their availability, among which linseed oil is the most significant one. Injection timing plays a major role among various injection parameters which affects its performance and emission characteristics. This paper focuses on experimental investigation on a single cylinder, four-stroke direct injection diesel engine with output of 5.2?kW at 1500?rpm at various injection timings, 20, 23, 26 degree BTDC for observing the performance and emission characteristics of direct injection diesel engine using methyl esters of linseed oil and its blends. The blends are B10, B20, and fuel characteristics are observed. The results show that when compared with diesel it gives an increase in BTHE and reduction in SFC. Both the biodiesel blends give lesser NOx. Slightly higher CO and HC emission were found. The performance and emissions were increased in when injection increased. 相似文献
42.
采用由氧化锌12g/L、氢氧化钠94 g/L、2-氨基-3-羧基吡啶4.2 g/L、四乙烯五胺17g/L、三乙醇胺2g/L、专利表面活性剂0.5 g/L及碳三氧化二铬(粒径2μm)0~ 11 g/L组成的镀液,于温度50℃、pH 6.5和电流密度4A/dm2的条件下,在低碳钢上电镀Zn-Cr2O3复合镀层.其显微硬度采... 相似文献
43.
T. Karthikeyan Arup Dasgupta S. Saroja M. Vijayalakshmi 《Journal of Materials Engineering and Performance》2005,14(2):241-248
The successful replacement of the present generation of corrosion-resistant materials (nitric acid-grade stainless steel and
Ti) by Ti-5Ta-1.8Nb, which has better corrosion resistance, depends on its weldability characteristics. This article presents
the results of a study on the fabrication, qualification, and microstructural characterization of the welds. Welding was carried
out using the direct current electrode negative (DCEN) polarity tungsten inert gas (TIG) (manual) welding method with high-purity
Ar shielding. Testing was carried out as per the ASME standard (section IX, welding and brazing). Qualification tests found
that the weldment met the required properties. The weldment showed heterogeneous microstructures, which are rationalized based
on differences in phase transformation mechanisms that are dictated by the thermal cycles experienced by various microscopic
regions. The results, described in this article, confirm that the weldability of the developmental Ti-Ta-Nb alloy is excellent.
A preliminary evaluation of the corrosion behavior of the welds showed rates comparable to that of the base metal, establishing
that this alloy could be considered as an alternative material for use in highly corrosive environments. 相似文献
44.
Dash Manmath Kumar Karthikeyan T. Mythili R. Vijayanand V. D. Saroja S. 《Metallurgical and Materials Transactions A》2017,48(10):4883-4894
Metallurgical and Materials Transactions A - This paper presents the results of microstructural evolution and mechanical properties in 304H Cu grade austenite stainless (SS 304HCu) during long-term... 相似文献
45.
Karthikeyan Rajan Thangaraju Shanmugasundaram Vadlamani Subramanya Sarma B. S. Murty 《Metallurgical and Materials Transactions A》2013,44(9):4037-4041
Nanocrystalline mechanically alloyed powders of 9Cr-1Mo ferritic steels with and without yttria dispersoids were densified using spark plasma sintering (SPS) to near-theoretical density at a temperature of 1073 K (800 °C). Studies on densification behaviour revealed that steels with dispersoids densified faster when compared to Fe-9Cr-1Mo steel. The evaluation of densification mechanisms during SPS reveals that grain boundary and lattice diffusion to be predominant at relative densities ranging from >0.7 to 0.9 in both the alloys. 相似文献
46.
Mercy J. Lilly Prakash S. Krishnamoorthy A. Ramesh S. Anand D. Alex 《Journal of Mechanical Science and Technology》2017,31(8):3777-3785
Journal of Mechanical Science and Technology - Self-healing materials heal partially or completely when damage occurs to restore the functionality of the material. Self-healing technology has found... 相似文献
47.
Power plants are one of the major industries suffering from severe erosion–corrosion (E‐C) problems resulting in substantial losses. One way of tackling this problem is by the use of thermal spray coatings. In the current investigation a new emerging technique i.e. cold spray coating process was used to deposit Ni‐20Cr and Ni‐50Cr powder on SA 516 (grade 70) boiler steel. The bare as well as the coated steels were subjected to cyclic experimental studies, in the superheater zone of a coal fired boiler. Weight change, thickness loss, XRD, FE‐SEM/EDS and X‐ray mapping techniques were used to analyse the eroded‐corroded specimens. The uncoated steel showed weight gain after exposure in the actual boiler environment, whereas, for the coated steels there was initial weight loss followed by negligible weight change. Based upon thickness loss data the cold‐sprayed Ni‐50Cr coating was found to provide better E‐C resistance than the Ni‐20Cr coating. 相似文献
48.
Krishnamoorthy A.V. Ron Ho Xuezhe Zheng Schwetman H. Jon Lexau Koka P. GuoLiang Li Shubin I. Cunningham J.E. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2009,97(7):1337-1361
We present a computing microsystem that uniquely leverages the bandwidth, density, and latency advantages of silicon photonic interconnect to enable highly compact supercomputer-scale systems. We describe and justify single-node and multinode systems interconnected with wavelength-routed optical links, quantify their benefits vis-a-vis electrically connected systems, analyze the constituent optical component and system requirements, and provide an overview of the critical technologies needed to fulfill this system vision. This vision calls for more than a hundredfold reduction in energy to communicate an optical bit of information. We explore the power dissipation of a photonic link, suggest a roadmap to lower the energy-per-bit of silicon photonic interconnects, and identify the challenges that will be faced by device and circuit designers towards this goal. 相似文献
49.
Kyle Kai-Hung Yu Karthikeyan S. M. Pillai Praveen R. Nalla Oliver Chyan 《Journal of Applied Electrochemistry》2010,40(1):143-149
On-chip microscopic corrosion, originating from contact of dissimilar metals, can cause serious reliability issues for integrated circuits and microelectromechanical devices. A new micropattern corrosion screening method combined with Tafel plots were employed to study Cu bimetallic corrosion in acid and base solutions relevant to the chemical–mechanical planarization process. The results demonstrated that Cu corrosion on Ru is much more severe compared to Cu corrosion on Ta substrates. Tafel plots confirm the nobility trend of Ru > Cu > Ta. The micropattern corrosion study shows the Cu bimetallic corrosion depends on specific chemicals and bimetallic contacts. Strong complexing ligands like NH3 combined with energetically favorable Cu/Ru bimetallic contact promote faster Cu corrosion under alkaline conditions (9 ≤ pH ≤ 11.4). Micropattern corrosion screening was shown to be useful in identifying the metastable surface layer during Cu corrosion and determining the optimal benzotriazole concentration for Cu corrosion inhibition. 相似文献
50.
This paper presents an experimental evaluation of the combined temporal and spectral processing methods for speaker recognition
task under noise, reverberation or multi-speaker environments. Automatic speaker recognition system gives good performance
in controlled environments. Speech recorded in real environments by distant microphones is degraded by factors like background
noise, reverberation and interfering speakers. This degradation strongly affects the performance of the speaker recognition
system. Combined temporal and spectral processing (TSP) methods proposed in our earlier study are used for pre-processing
to improve the speaker-specific features and hence the speaker recognition performance. Different types of degradation like
background noise, reverberation and interfering speaker are considered for evaluation. The evaluation is carried out for the
individual temporal processing, spectral processing and the combined TSP method. The experimental results show that the combined
TSP methods give relatively higher recognition performance compared to either temporal or spectral processing alone. 相似文献