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Details the process whereby several pyrazole disperse dye derivatives are synthesized. Tests these dyes for dyeing characteristics on nylon, polyester and cellulose acetate fabrics as disperse dyes. Also determines properties such as washing, perspiration and rubbing fastness of the dyed fabrics.

In recent years heterocyclic azo dyes have been the subject of an intense research by dye manufacturers. Even so, little has been devoted to technical properties, so we have recently directed our research activities towards studying the ability of thiazole azo and hydrazono disperse dyes for dyeing of polyester and cellulose acetate.

Describes the synthesis and testing of a group of dyes, derived from heterocyclic compounds containing thiazole ring systems. Gives a comparative analysis of the dyes’ washing, perspiration and rubbing fastness when applied to synthetic fabrics.

The notable dyeing performance and characteristics of polyfunctional heterocyclic azo dyestuff promoted us to design a programme specifically aiming to investigate efficient synthesis of several new isoxazole azo dyes. In the present work we investigate the dyeing performance of the newly synthesized isoxazole azo dyes.

A new series of the title pyrazole azo dye systems has been synthesized. The new dyes are applied on nylon and cellulose acetate fibers to give dyed fabrics with excellent properties of colour intensity and fastness properties. The physical and spectral data of the investigated dyes are illustrated. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are discussed. The data of these studies are listed. The colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

The purpose of this study is to illustrate that Reformism dominates much of Arab thought, and it has continued to be a major source of inspiration for contemporary Islamic philosophy. Thereafter, it shows that Amin Elkholy was a pioneer of reformism whose innovative thinking led Abd-el-Jabaar Elrefa’I and others to recognize him as the first hermeneuticist in the history of Islam.

The research traces Islamic Reformism's rise and development, evaluates its status in the map of modern Arab/Islamic thought and determines its main figures until arriving at Amin Elkholy. Then, it shows that through evolutionism and a comprehensive evolutionistic approach, Elkholy undertook renewal in Islamic reformism as a multidimensional innovation. So, the interaction between traditional renovation and Western evolutionism produced a highly fruitful philosophy of innovation and progress.

First, Islamic Reformism contains potential for continuous advancement and development. Second, Amin Elkholy has introduced a model of Islamic Reformism and achieved the situation of authenticity/modernization in a way that seems very compatible with our postmodernism era and postmodernist philosophy.

The research framework has been Modern Arab Thought and Contemporary Islamic Philosophy since the beginning of the 19th Century. The approach entails some future expectations.

The approach entails some future expectations and suggests topics for further research.

To the best of the author’s knowledge, it is the first time to notice some compatibility between Islamic Reformism and postmodernism.

This work aims to synthesize a series of novel acyclic and/or heterocyclic systems, as precursors for dyes with potential antimicrobial activity that could be used for simultaneous dyeing and antimicrobial textile finishing. Thus, a series of novel pyridine, thiophene and pyrazolo[3,4-b]pyridine derivatives were synthesized, and their antimicrobial and textile finishing properties were studied and evaluated.

The synthesis, structure elucidation and antimicrobial activities of the newly synthesized compounds based on 4,4-dicyano-3-phenyl-but-3-enoic acid phenylamide (1) were demonstrated. The minimal inhibitory concentration in μg/mL of the compounds showed significant antimicrobial activity against most of the tested organisms. On the other hand, their spectral characteristics and fastness properties were measured and evaluated. Antimicrobial activities of the dyed fabrics in terms of inhibition zones (mm) were measured and evaluated.

A series of novel heterocyclic compounds (Schemes 1-3) were synthesized based on starting material (1). Compounds (1), 2, 4a, 8a and 9c exhibited comparable or even higher antibacterial activities than the selected standards (ampicillin), while compounds 2, 3c, 3d, 4a and 8b revealed higher antifungal activities than the selected standard (cycloheximide). On the other hand, some dyes showed high antimicrobial evaluation on the dyed fabrics (nylon 66, acetate and polyester) expressed as size (mm) of inhibition zones (Tables I-IV).

Results revealed that many hydrazo and azo derivatives were synthesized from some pyridines and thiophenes. The antimicrobial evaluation and textile finishing of the newly synthesized products revealed significant and potent values of antimicrobial activity.

All the synthesized compounds were novel and most of them exhibited higher antimicrobial activities than the selected standards antibiotics, thus are valuable for simultaneous dyeing and antimicrobial functional finishing of textile fabrics.

Three series of azo dye systems are considered, namely, 5‐oxo‐2‐pyrazoline azo dye systems 9 a‐d,1‐oxo‐pyrazolo pyrazole azo dye systems 10 a, b, c, e, 11 a, b, c, e, 12 a, b, c, e, 13 a‐d and 6‐oxo‐pyranopyrzole azo dye systems 14 a‐d. The shifts of ultraviolet‐visible absorption maxima affected by the structural configuration of the pyrazole dye systems are investigated. The structural effects of the polyfunctionally substituted pyrazole dye systems on the intensity of colour and fastness properties of the dyed fabrics are also discussed. The data of these studies are listed. Colour shades of the synthesized dyes on nylon and acetate fabrics are indicated.

This study aims to represent a successful simple method for the synthesis of some novel dyes based on thiazole derivatives and their applications in textile printing.

2-(benzo[d]thiazol-2-ylmethyl)thiazol-4(5H)-one compound is prepared by convention heating and microwave technique then used as a coupling agent, which reacts with different diazonium Salt to form diazo dyes.

The synthesized diazo dyes are confirmed via spectral data (IR,1H-NMR, 13C-NMR and Mass spectra). The dyes are used to print polyester fabric. The obtained results clarified that the prints have good color strength, brilliant color and highly durable antibacterial activity.

The authors designed efficient synthesis for some novel thiazolone dyes. The novel procedure features short-reaction time, very good yields and a simple workup. The authors studied the antibacterial activity and their application in printing polyester fabrics.

Granular flow lubrication is developed in recent years as a new lubrication method which can be used in extreme environments, while the stick-slip mechanisms of granular flow lubrication are an urgent obstacle remains unsolved in fully establishing the granular flow lubrication theory.

A granular flow lubrication research model is constructed by the discrete element method. Using this numerical model, the mesoscopic and macroscopic responses of stick-slip that influenced by the shear velocity, and the influence of the shear velocity and the normal pressure on the vertical displacement are studied.

Research results show that movement states of granular flow lubrication medium gradually transform from the stick-slip state to the sliding state with increased shear velocity, in which these are closely related to the fluctuations of force chains and friction coefficients between granules. The stick-slip phenomenon comes up at lower shear velocity prior to the appearance of granular lift-off between the two friction pair, which comes up at higher shear velocity. Higher normal pressure restrains the dilatation of the granular flow lubrication medium, which in turn causes a decrease in the displacement.

These findings reveal the stick-slip mechanism of granular flow lubrication and can also offer the helpful reference for the design of the new granular lubrication bearing.