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101.
Environmental concerns and limited resource of petroleum fuels have caused interests in the development of alternative fuels for internal combustion (IC) engines. For diesel engines, alcohols are receiving increasing attention because they are oxygenated and renewable fuels. Therefore, in this study, the effect of injection timing on the exhaust emissions of a single cylinder, naturally aspirated, four-stroke, direct injection diesel engine has been experimentally investigated by using methanol-blended diesel fuel from 0% to 15% with an increment of 5%. The tests were conducted for three different injection timings (15°, 20° and 25 °CA BTDC) at four different engine loads (5 Nm, 10 Nm, 15 Nm, 20 Nm) at 2200 rpm. The experimental test results showed that Bsfc, NOx and CO2 emissions increased as BTE, smoke opacity, CO and UHC emissions decreased with increasing amount of methanol in the fuel mixture. When compared the results to those of original injection timing, NOx and CO2 emissions decreased, smoke opacity, UHC and CO emissions increased for the retarded injection timing (15 °CA BTDC). On the other hand, with the advanced injection timing (25 °CA BTDC), decreasing smoke opacity, UHC and CO emissions diminished, and NOx and CO2 emissions boosted at all test conditions. In terms of Bsfc and BTE, retarded and advanced injection timings gave negative results for all fuel blends in all engine loads. 相似文献
102.
103.
Murat Manguoglu Ahmed H. Sameh Tayfun E. Tezduyar Sunil Sathe 《Computational Mechanics》2008,43(1):73-80
We present an effective preconditioning technique for solving the nonsymmetric linear systems encountered in computation of
incompressible flows in long domains. The application category we focus on is arterial fluid mechanics. These linear systems
are solved using a nested iterative scheme with an outer Richardson scheme and an inner iteration that is handled via a Krylov
subspace method. Test computations that demonstrate the robustness of our nested scheme are presented. 相似文献
104.
Optimal Distributed Location Management in Mobile Networks 总被引:4,自引:0,他引:4
Krishnamurthi Govind Azizoğlu Murat Somani Arun K. 《Mobile Networks and Applications》2001,6(2):117-124
An important issue in the design of future Personal Communication Services (PCS) networks is the efficient management of location information. In this paper, we consider a distributed database architecture for location management in which update and query loads of the individual databases are balanced. We obtain lower bounds to the worst-case delay in locating a mobile user, to the average delay, and to the call blocking probability. We then propose a dynamic location management algorithm that meets these lower bounds. The optimality of this algorithm with respect to these three performance measures, as well as simplicity, make it an appealing candidate for distributed location management in PCS networks. 相似文献
105.
Murat Oztas Peter Rojan 《流程工业》2008,(1):56-57
通过将滤布翻转过来的方法将过滤出来的固体物质排出,这一获取高价值过滤材料的基本方法30多年来一直被成功使用,没有改变。然而现在一切似乎都在悄悄地发生着变化,本文所介绍的德国Heinkel公司第三代翻袋过滤器式离心机就印证了这种变化。 相似文献
106.
Synthesis and characterization of a Zr‐containing silicate‐based epoxy‐functional polymer nanocomposite system 下载免费PDF全文
As a continuation of efforts to explore the potential of certain types of polymer nanocomposites to be successful candidates as dental restoration/adhesion materials, a Zr‐containing and organically modified silicate‐based material system with epoxy functionality was prepared by use of a sol–gel synthesis method, and UV light‐ and visible light (VL)‐curing processes. Comparative influences of the synthesis and processing parameters on the mechanical, thermal, and microstructural/nanostructural properties of the system were detailed. Zr‐containing species proved to more effectively catalyze the epoxy polymerization/crosslinking reactions than those containing Ti. Incorporation of Zr into the nanocomposite network led to significantly advanced mechanical properties. An elastic (Young's) modulus value of 23 MPa was achieved. The system with relatively high Zr content was successfully obtained, which also had higher thermal stability. Overall observations and results suggested that Zr content, and the UV light‐ or VL‐curing process could be capitalized on to modify the structure, and to improve the final properties of these material systems, which indicated a prospective opportunity for this material system to be utilized in dental restoration/adhesion applications. POLYM. ENG. SCI., 55:792–798, 2015. © 2014 Society of Plastics Engineers 相似文献
107.
Carolin Braun Eduard Spuling Niklas B. Heine Murat Cakici Martin Nieger Stefan Brse 《Advanced Synthesis \u0026amp; Catalysis》2016,358(10):1664-1670
Pyridyl‐substituted [2.2]paracyclophanes build a multifunctional structural motif that is useful in material chemistry, catalysis and for luminescent structures. Nonetheless, there is still a lack of general methods for the synthesis of these structures tolerating easily accessible bromides as well as different isomeric pyridyl groups. Hence the coupling of functionalized [2.2]paracyclophanes with various substituted and functionalized pyridyl derivatives was achieved using Stille, Suzuki and Kumada coupling conditions. Hereby the Stille coupling of a [2.2]paracyclophane is presented as a versatile reaction for the formation of heteromeric [2.2]paracyclophane‐containing biaryl structures.
108.
109.
Ayhan Baştürk Şebnem Badem M. Murat Ceylan 《European Journal of Lipid Science and Technology》2023,125(9):2200213
In this study, safflower oil oleogels were made using propolis wax and carnauba wax in three different concentrations each, and their effectiveness as a fat substitute in cake was evaluated afterward. Oleogels' oxidative stability and characterization were looked into. In oleogels, the oil binding capacity, solid fat content, and crystallization time were all assessed. The cakes underwent an examination for moisture content, texture, and sensory evaluation. Additionally, analyses of fatty acid composition, free fatty acidity, oxidative stability (peroxide value, conjugated diene-triene), 3-monochloropropane-1,2-diol (3-MCPD), and glycidyl were carried out both before and after baking in oleogels and shortening. Several of the physical, textural, and sensory qualities of the oleogel-based cakes were acceptable when compared to those of the shortening-based cakes. The general acceptability of cakes made with carnauba wax was very high and almost under control. The acceptability of cakes made with propolis wax oleogels was lower than this. The study of these criteria has shown that safflower oil-based carnauba and propolis wax oleogels can be utilized to produce high-quality, healthful cakes with a high amount of unsaturated fatty acids. Practical Applications : To replace fat phases in cake products high in saturated fatty acids and to enhance the fatty acid profile of the cakes, safflower oil-based oleogels with propolis wax and carnauba wax are a very good option. The results obtained provide useful information for the production of high-quality cakes with higher unsaturated fatty acid content, recommended for a healthier diet, with these oleogels containing different concentrations of oleogelator. 相似文献
110.
In an effort to explore the potential of certain types of polymer nanocomposites to be successful candidates as dental restoration/adhesion materials, a Ti‐ or Zr‐containing and organically modified silicate‐based material system with epoxy functionality was prepared by use of a sol–gel synthesis method, and ultraviolet light‐ and visible light (VL)‐curing processes. Comparative influences of certain synthesis/processing parameters on the properties of the system were detailed. It was shown that both Ti‐ and Zr‐containing species could play significant roles in determining the structure and hence the properties of the nanocomposites. VL‐curing was demonstrated to be a relatively advantageous process that could be employed in applications such as dental restoration/adhesion. Moreover, the mechanical properties of the nanocomposites were shown to be promisingly high. Overall observations and results indicated a prospective opportunity for this material system to be utilized in dental restoration/adhesion applications. POLYM. COMPOS., 35:1879–1887, 2014. © 2014 Society of Plastics Engineers 相似文献