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161.
A series of novel 4-arylazo-3-hydroxythiophene disperse dyes was synthesized by heterocyclization of ethyl 2-arylhydrazono-2-phenylthiocarbamoyl
acetates with a variety of α-halogenated reagents. The structures of the synthesized dyes were confirmed by UV-Vis, IR, 1H NMR, and MS spectroscopic techniques and elemental analysis. The dyes were applied to conventional polyester fabric by high
temperature exhaust dyeing. These dyes were found to give orange to reddish-violet shades with very good depth, levelness,
and brightness on polyester fabric. The dyed fabric showed moderate to good light fastness and very good fastness to washing
and perspiration. Also the position of color in CIELAB coordinates (L*, a*, b*, H*, and C*) was assessed. 相似文献
162.
A series of novel 4-arylazo-3-hydroxythiophene disperse dyes was synthesized by heterocyclization of ethyl 2-arylhydrazono-2-phenylthiocarbamoyl
acetates with a variety of α-halogenated reagents. The structures of the synthesized dyes were confirmed by UV-Vis, IR, 1H NMR, and MS spectroscopic techniques and elemental analysis. The dyes were applied to conventional polyester fabric by high
temperature exhaust dyeing. These dyes were found to give orange to reddish-violet shades with very good depth, levelness,
and brightness on polyester fabric. The dyed fabric showed moderate to good light fastness and very good fastness to washing
and perspiration. Also the position of color in CIELAB coordinates (L*, a*, b*, H*, and C*) was assessed.
Correspondence: Ehab Abdel-Latif, Department of Chemistry, Faculty of Science, Mansoura University, 35516 Mansoura, Egypt 相似文献
163.
S. Jha C. Mitros Amer Lahamer Sherif Yehia Glenn M. Julian R. A. Dunlap G. Stroink Z. M. Stadnik 《Hyperfine Interactions》1989,50(1-4):607-612
Mössbauer effect studies of57Co-doped La2CuO4?y were performed at temperatures between 4.2 K and room temperature. These confirm the antiferromagnetic ordering of these compounds below room temperature. Temperature dependence of the quadrupole splitting shows that the hyperfine field is at an angle with thec-axis. 相似文献
164.
A sensitive spectrophotometric procedure is described for the determination of 1,4-benzodiazepine (clorazepate dipotassium) in the presence of its degradation products. The procedure is based on acid hydrolysis of clorazepate dipotassium to yield its final degradation products viz., 2-amino-5-chlorobenzophenone and glycine. The amino-chlorobenzophrenone is extracted from the neutralized hydrolysate with diethyl ether, the extract is evaporated, the residue is dissolved in methanol and its absorbance measured at about 240 nm or 380 nm. Glycine, left in the aqueous layer after etherial extraction of aminochlorobenzophenone, is treated with ninhydrin reagent in the presence of pyridine and the bluish violet colour formed is measured at about 560 nm. The suggested procedures determine 20–100 mg of clorazepate dipotassium via its degradation products aminochlorobenzophenone and glycine with mean accuracies of 100.0 ± 0.5% at 560 nm, 100.2 ± 0.6% at 380 nm and 99.8 ± 0.5%. The suggested procedures are suitable for stability-testing of clorazepate dipotassium in bulk powder and in pharmaceutical preparations. 相似文献
165.
Synthesis of Novel Fused Heterocycles Based on 6‐Amino‐4‐phenyl‐2‐thioxo‐1,2‐dihydropyridine‐3,5‐dicarbonitrile
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H. Abdel‐Ghany A. M. El‐Sayed A. A. Amer A. M. Ahmed 《Journal of heterocyclic chemistry》2016,53(6):2013-2019
Under phase transfer catalysis conditions, 6‐amino‐4‐phenyl‐2‐thioxo‐1,2‐dihydropyridine‐3,5‐dicarbonitrile ( 1 ) was allowed to react with halo compounds, acrylonitrile, chloroacetyl chloride, ethyl cyanoacetate, formamide, triethylorthoformate, or formic acid to give new derivatives of fused pyridines 2–22, respectively. Acetylation of compound 1 using acetic anhydride afforded product 23 , which in turn underwent intramolecular cyclization in pyridine to give the corresponding pyrido[2,3‐d]pyrimidine 24 . 相似文献
166.
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169.
This paper presents a study of the non-linear response of a simple rigid disk-rotor, supported by active magnetic bearings (AMB), without gyroscopic effects. The case of primary resonance is examined under multi-excitation forces. The rotating shaft is described by a coupled second order non-linear ordinary differential equations. Approximate solutions are sought applying the method of multiple scales. Numerical simulations are carried out to illustrate the steady-state response and the stability of the solutions for various parameters using the frequency response function method. It is shown that the system parameters have different effects on the non-linear response of the rotor. For steady-state response, however, multiple-valued solutions and jump phenomenon occur. Results are compared to previously published work. 相似文献
170.
Amer H. H. Al-Khaladi 《Results in Mathematics》2010,57(3-4):313-318
This paper studies the problem on meromorphic functions sharing one small function with their kth derivative. The result here improves and generalizes some results of Al-Khaladi (Result Math 47:1–5, 2005), Brück (Result Math 30:21–24, 1996) and Zhang (Kodai Math J 21:179–184, 1998). 相似文献