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101.
102.
A bifunctional reactive disperse dye containing two temporarily anionic sulphatoethylsulphone groups was synthesised and applied to nylon 6 fabric by exhaust dyeing at a variety of pH levels and temperatures. A monofunctional reactive disperse dye containing one temporarily anionic sulphatoethylsulphone group was also synthesised, and its dyeing behaviour was compared with the bifunctional dye. The bifunctional reactive disperse dye exhibited high exhaustion and total fixation yield under alkaline conditions. The results also indicate that the introduction of two temporarily anionic sulphatoethylsulphone groups of the bifunctional dye gave an enhancement in dyeing performance compared with that of the monofunctional dye. The dyes also showed very good levelling and fastness properties on nylon 6 fabric. 相似文献
103.
Saoud A. M. Metwally Mohamed S. K. Youssef Mansour I. Younes 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1980,30(1):513-519
1-Hydroxy and/or 1-aminoanthraquinone was allowed to react with formaldehyde in an alkaline medium to give 1-hydroxy or 1-amino-2-hydroxymethyl-9,10-dihydroxy-anthracenes, which gave on air oxidation, hydroxymethylanthraquinone derivatives (I). Interaction of 1-amino-2-hydroxymethylanthraquinone or its 4-bromo derivative with carbonyl compounds in the presence of an acid catalyst gave (1,3)oxazine derivatives (II). The methylene group in position-2 of the (1,3)oxazine ring was found to be highly reactive and reacted with carbonyl compounds to form the corresponding arylidenes (III). Selective oxidation of dimethyl oxazine derivatives with SeO2 gave the corresponding dialdehyde (IV), which interacted with aromatic amines to give the corresponding Schiff bases (V). The bromine atom in the 6-position of II was easily replaced by aromatic amines to give blue disperse dyes (VI). 相似文献
104.
105.
Mustafa Bozkurt Mark Harman Youssef Hassoun 《Software Testing, Verification and Reliability》2013,23(4):261-313
Service‐oriented architecture (SOA) is gaining momentum as an emerging distributed system architecture for business‐to‐business collaborations. This momentum can be observed in both industry and academic research. SOA presents new challenges and opportunities for testing and verification, leading to an upsurge in research. This paper surveys the previous work undertaken on testing and verification of service‐centric systems, which in total are 177 papers, showing the strengths and weaknesses of current strategies and testing tools and identifying issues for future work. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
106.
In this paper a cylindrical model of human body exposed to the extremely low frequency (ELF) electromagnetic field is presented. The analysis is based on the solution of the simplified integral equation for thick wires. The numerical solution of the integral equations is performed by the Galerkin–Bubnov variant of the boundary element method. Several numerical results for the ELF exposures are presented. 相似文献
107.
Youssef F. Rashed 《计算机、材料和连续体(英文)》2004,1(4):319-326
The present paper develops a new technique for treatment of self-weight for building slabs in the boundary element method (BEM). Due to the use of BEM in the analysis, all defined variables are presented on the slab boundary (mesh is defined only along the slab boundary). Self-weight, however, is usually defined over slab domain, hence domain discretisation is required, which spoils the main advantage of the BEM. In this paper a new method is presented to transform self-weight domain integrals to the boundary for such slabs. The proposed method is based on using the so-called Green's first identity. All new kernels for generalized displacements, stress-resultants, and tractions are derived and listed explicitly. The present formulation is implemented into computer code and several examples are tested. Results are compared against results obtained from other numerical method to prove the accuracy and validity of the present formulation. 相似文献
108.
Ahmed M. Youssef Norbert H. Maerz 《Bulletin of Engineering Geology and the Environment》2012,71(1):171-186
The Missouri Rock Fall Hazard Rating System (MORFH RS) was recently developed for the State of Missouri. It is a system that separates the risk of failure from the consequences of failure factors, thus allowing better assessment of the hazards of rock falls. Efficiency is gained by video logging of highway rock cuts from vehicles moving at highway speeds, pre-screening of rock cuts from video images, making some of the measurements needed for the rating system on digital images, and using GPS receivers to collect field data and GIS to organize all the data. This paper describes the rationale behind the parameters selected for the system using factor analysis and other methods and the verification of the system through sensitivity studies and multiple rater tests. Simulations of remediation techniques were applied to recognize the most effective methods for remediation. 相似文献
109.
The production of cationised cotton fabrics, via Sandene 8425, 1, 1-dimethyl-3-hydroxy azetidinium chloride and 1, 1-diethyl-3-hydroxy azetidinium chloride, greatly enhances the exhaustion and fixation of acid dyes. This paper shows that these dyes can be used in the absence of salt in a neutral medium. Wash fastness, light fastness and other properties were studied. 相似文献
110.