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161.
Emissions of greenhouse gases such as CO2, CO, CH4 and NOX from fossil fuel use are implicated in climate change. The use of bioethanol is one means to reduce fossil fuel use and emissions of greenhouse gases. This study investigated research to produce ethanol from sugar beet and use as fuel in Turkey. The calculated demand for bioethanol amounted to some 220,000 m3 where a 5% ethanol mix in petrol was used. Turkey has the potential to produce 30 million ton of sugar beet, which is sufficient to meet the bioethanol demand. 相似文献
162.
Mehmet Uz D. K. Rehbein O. N. Carlson 《Metallurgical and Materials Transactions A》1986,17(11):1955-1966
Thermotransport experiments were performed on two-phase V-C and Nb-C alloys for various times, temperature ranges, and compositions.
A one-phase region develops in the hotter portion of the sample accompanied by an increase in carbide concentration in the
colder region. A mathematical equation in which the direction of transport is described by the sum of the heat of solution,A―H, and the heat of transport,Q*, was fitted to the experimental data for all of the alloys studied. No evidence was found to support the physical motion
of the carbide particles predicted by some models. On the assumption that local equilibrium exists between the particles and
the matrix, points on the V-C solvus were determined from the temperature corresponding to the one-phase/two-phase interface
in the different experiments. The solid solubility for carbon in vanadium was determined to be log C (at. pct C) = 2.918 -
4536/T with a heat of solution of 86.8 ± 2.9 kJ/mol.
Formerly a Graduate Research Assistant, Ames Laboratory, Iowa State University 相似文献
163.
164.
The dehydration behaviors of two different hydrated zinc borate species, Zn[B3O3(OH)5] · H2O and Zn[B3O4(OH)3], which are industrially important flame retardants, were studied by thermal gravimetric(TG) analysis and in situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. Dehydration onset temperatures of Zn[B3O3(OH)5] · H2O and Zn[B3O4(OH)3] were 129 and 320°C, respectively, at a 10°C/min ramp rate. A very small amount of boric acid was volatilized in addition to water vapor when both samples were heated at 250°C. A significant amount of water vapor was adsorbed by Zn[B3O3(OH)5] · H2O from air at 25°C. However, Zn[B3O4(OH)3] adsorbed a very small amount of water under the same conditions. Both zinc borates did not have a tendency to cake during storage. 相似文献
165.
This review summarizes the studies related to chemical functionalization of polysulfones used in many different applications such as membranes with special functions, nanocomposites, biofilm formation, fuel cells etc. reported in recent years from the literature since 2000. Various strategies have been applied for the functionalization of polysulfones. One strategy is to add desired functionality into starting monomers in the solution containing the main components of commercial polysulfones, the aromatic dihalide sulfone and bisphenol monomers, or to functionalize the related monomers before the condensation. Another approach is to form difunctional polysulfone oligomers. Then, functional groups can be utilized to react with monomers or other polymers to obtain functional polymers or block copolymers. The most applied method is post‐modification of commercially available polysulfones by incorporation of functional groups to their aromatic groups and their use in the formation of graft polymers or polysulfone‐based networks. © 2013 Society of Chemical Industry 相似文献
166.
Perturbation–iteration theory is systematically generated for both linear and nonlinear second-order differential equations and applied to Bratu-type equations. Different perturbation–iteration algorithms depending upon the number of Taylor expansion terms are proposed. Using the iteration formulas derived using different perturbation–iteration algorithms, new solutions of Bratu-type equations are obtained. Solutions constructed using different perturbation–iteration algorithms are contrasted with each other as well as with numerical solutions. It is found that algorithms with more Taylor series expansion terms yield more accurate results. 相似文献
167.
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169.
Relations are developed for first‐ and second‐law analyses of the simple Linde–Hampson cycle used in gas liquefaction systems. An expression for the minimum work requirement, which is applicable to any gas liquefaction system, is developed with the help of a Carnot refrigerator. It is shown that the minimum work depends only on the properties of the incoming and outgoing gas streams and the environment temperature. Numerical calculations are performed to obtain the performance parameters of different gases while parametric studies are done to investigate the effects of liquefaction and inlet gas temperatures on various first‐ and second‐law performance parameters. As the liquefaction temperature increases and the inlet gas temperature decreases, the liquefied mass fraction, the coefficient of performance (COP) and the exergy efficiency increase while actual and reversible work consumptions decrease. The exergy efficiency values appear to be low, indicating significant potential exists for improving efficiency and thus decreasing the required work consumption for a specified amount of liquefaction. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
170.
Multirelational k-Anonymity 总被引:1,自引:0,他引:1
Nergiz Mehmet Ercan Clifton Christopher Nergiz Ahmet Erhan 《Knowledge and Data Engineering, IEEE Transactions on》2009,21(8):1104-1117
k-Anonymity protects privacy by ensuring that data cannot be linked to a single individual. In a k-anonymous data set, any identifying information occurs in at least k tuples. Much research has been done to modify a single-table data set to satisfy anonymity constraints. This paper extends the definitions of k-anonymity to multiple relations and shows that previously proposed methodologies either fail to protect privacy or overly reduce the utility of the data in a multiple relation setting. We also propose two new clustering algorithms to achieve multirelational anonymity. Experiments show the effectiveness of the approach in terms of utility and efficiency. 相似文献