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61.
62.
Gozde Tansuğ Nur Kicir Onur Demirkol Elife Sultan Giray Tunc Tuken 《Journal of Adhesion Science and Technology》2016,30(18):1984-2000
Phenyldithiocarbamate compound has been synthesized and studied as corrosion inhibitor for steel. Dithiocarbamate (DTC) compounds with linear alkyl groups are good inhibitors, but their stability is quite low in acidic solutions. It should be noted that long-term stability is important for practical applications, in order to avoid excess use of chemicals. So, we have synthesized phenyl substituted DTC which offers strong inhibition efficiency and extra stability. This new inhibitor is chemically adsorbed on steel through its DTC group, while the aromatic ring provides extra stability and long-term efficiency. For the assessment of corrosion kinetics, we have utilized potentiodynamic and ac impedance studies; also solution assay analysis was realized with atomic absorption spectroscopy. It was revealed that inhibitor exhibits remarkably high efficiency, even under elevated temperature conditions. At 55 °C temperature conditions, icorr value decreased from 5050 to 154 μA cm?2, with the addition of 500 ppm inhibitor. The long-term stability of inhibitor was also tested and 85.93% efficiency was obtained after three days of exposure period for 500 ppm concentration. 相似文献
63.
64.
Benjamin P. Thompson Stuart D. Anderson Jeffrey S. Russell Awad S. Hanna 《Canadian Metallurgical Quarterly》2002,18(3):129-137
This paper presents guidelines for implementing the construction warranty contracting method in the highway construction industry. A logical, step-by-step method for effectively applying the warranty contracting program for use in the highway construction industry is developed. Relevant issues that may present obstacles to the implementation are addressed, while the best practices, compiled from an evaluation of the current industry’s state-of-the-art practices, will assist an interested state highway agency in creating a warranty specification. In performing this research, the current use of warranty specifications among state highway agencies was examined, and an in-depth case study of the Wisconsin Department of Transportation’s warranty program was conducted. 相似文献
65.
Mainstream American journalism rests on a pluralist model of democracy that conserves the status quo, essentializes culture, and trivializes diversity. A very different understanding of diversity emerges from a multiculturalist perspective that questions existing arrangements, posits a relational view of culture, and defines diversity in terms of patterns of discrimination and inequality. A case study of coverage of a local issue in the mainstream and minority press underpins a discussion of the importance of diversifying journalism by restructuring the American press. Journalism diversity matters most not only as it heightens sensitivity to cultural differences but as it strengthens the role of minority media in the struggle to achieve the social justice and political parity that a culturally diverse society demands. 相似文献
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67.
This paper provides a continuation of ideas presented by Davvaz and Mahdavipour [B. Davvaz, M. Mahdavipour, Roughness in modules, Inform. Sci. 176 (2006) 3658-3674]. The notion of hypermodule is a generalization of the notion of module. In this paper, we consider the quotient hypermodule M/A and interpret the lower and upper approximations as subsets of the quotient hypermodule M/A. Then, we introduce the concept of quotient rough sub-hypermodule. Also, using the concept of fuzzy sets, we introduce and discuss the concept of fuzzy rough hypermodules and then we obtain the relation between fuzzy rough sub-hypermodules and level rough sets. This relation is characterized as a necessary and sufficient condition. 相似文献
68.
Mohamed Fawzy Ramadan Mohamed Mostafa Afify Amer Ahmed El-Said Awad 《European Food Research and Technology》2008,227(4):1173-1182
Coriander (Coriandrum sativum L.) seed oil (COR) is a promising oil with high levels of bioactive compounds. Very little information, however, is available
on the effect of administration of COR on different aspects of plasma lipid profile in experimental animals. In view of the
important implications, the effect of administration of COR and oil blend [a mixture of soybean oil, coriander oil and sunflower
oil (4:2:4, w/w/w; Blend)] on the profile of plasma lipids was investigated in 24 male albino rats placed on a cholesterol-rich
(1%) basal diet as compared to rats on a cholesterol-free basal diet. Coriander seed oil and Blend were analyzed for composition
of fatty acid, sterol and tocopherol. The levels of bioactive compounds (sterols and tocopherols) were higher in COR than
in the Blend. In addition, the antiradical potential of COR and Blend was measured and the results showed that COR had stronger
radical scavenging activity than Blend. In the biological experiment, rats were divided into four diet groups. The negative
control group (control) consumed the basal diet (BD) only, which contained wheat starch, casein and cellulose, as well as
mineral and vitamin mixtures. To the BD were added 1 g/100 g cholesterol (Chol/group), or both (Chol/COR group) and (Chol/Blend
group). The groups did not differ before the experiment, which lasted 60 days. Plasma total lipids (TL), triacylglycerols
(TAG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and high-density lipoprotein-cholesterol (HDL-C) were measured at day 15, 30, 45 and 60 during the experiment period. Generally, COR and Blend-supplemented diets decreased
the levels of TL, TC, TAG and LDL-C in plasma. In addition, significant increase in the levels of HDL-C was observed for Chol/COR
and Chol/Blend groups. The results demonstrated that COR, and to a relatively lesser degree Blend, have hypocholesterolemic
properties in rats fed a cholesterol-rich diet. 相似文献
69.
As part of graduation requirements, the Department of Civil Engineering at the University of Wisconsin-Madison requires a minimum of one three credits course in a capstone design experience. The main objective of this course is to allow students the opportunity of undertaking and completing an open-ended design project. Supervision of the projects is performed by practicing engineers and department faculty. The course is a practice oriented design class that integrates several civil engineering areas. Special emphasis is placed on integrating constructability concepts with structural engineering, mechanical systems, electrical systems, and other project details. Student groups not only complete project designs, but also perform feasibility studies, value engineering, and prepare a construction schedule and cost estimate based on the designs they have generated. The objective of this paper is to describe the senior level capstone design experience at the University of Wisconsin-Madison. 相似文献
70.
Effect of sampling jitter on some sine wave measurements 总被引:3,自引:0,他引:3
The effect of sampling jitter on some periodic signal measurements, namely, the amplitude and phase of a pure sinusoid, is investigated. The parameters are determined by the fast Fourier transform (FFT) algorithm, which is used for manipulating samples in a data-acquisition system. Results are expressed in terms of mean values and variances of the measured parameters. Computer simulation results, based on Gaussian jitter, show the changes of amplitude and phase standard deviations versus the changes of standard deviation of jitter and signal amplitude for different numbers of FFT points 相似文献