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951.
Non-Newtonian ink transfer in gravure-offset printing 总被引:2,自引:0,他引:2
Fatemeh GhadiriDewan Hasan Ahmed Hyung Jin Sung Ebrahim Shirani 《International Journal of Heat and Fluid Flow》2011,32(1):308-317
The inks used in gravure-offset printing are non-Newtonian fluids with higher viscosities and lower surface tensions than Newtonian fluids. This paper examines the transfer of a non-Newtonian ink between a flat plate and a groove when the plate is moved upward with a constant velocity while the groove is held fixed. Numerical simulations were carried out with the Carreau model to explore the behavior of this non-Newtonian ink in gravure-offset printing. The volume of fluid (VOF) method was implemented to capture the interface during the ink transfer process. The effects of varying the contact angle of the ink on the flat plate and groove walls and geometrical parameters such as the groove angle and the groove depth on the breakup time of the liquid filament that forms between the plate and the groove and the ink transfer ratio were determined. Our results indicate that increasing the groove contact angle and decreasing the flat plate contact angle enhance the ink transfer ratio and the breakup time. However, increasing the groove depth and the groove angle decreases the transfer ratio and the breakup time. By optimizing these parameters, it is possible to achieve an ink transfer from the groove to the flat plate of approximately 92%. Moreover, the initial width and the vertical velocity of the neck of the ink filament have significant influences on the ink transfer ratio and the breakup time. 相似文献
952.
Sanaz Khan-Afshar Umair Siddique Mohamed Yousri Mahmoud Vincent Aravantinos Ons Seddiki Osman Hasan Sofiène Tahar 《Mathematics in Computer Science》2014,8(1):39-70
Optical systems are becoming increasingly important by resolving many bottlenecks in today’s communication, electronics, and biomedical systems. However, given the continuous nature of optics, the inability to efficiently analyze optical system models using traditional paper-and-pencil and computer simulation approaches sets limits especially in safety-critical applications. In order to overcome these limitations, we propose to employ higher-order-logic theorem proving as a complement to computational and numerical approaches to improve optical model analysis in a comprehensive framework. The proposed framework allows formal analysis of optical systems at four abstraction levels, i.e., ray, wave, electromagnetic, and quantum. 相似文献
953.
Idris Cerkez Hasan B. Kocer S. D. Worley R. M. Broughton T. S. Huang 《Cellulose (London, England)》2012,19(3):959-966
Three heterocyclic N-halamine structures containing amine, amide, or both functional groups were immobilized onto cotton fabric through epoxide
tethering. The coatings were rendered biocidal upon exposure to dilute household bleach solution. The coatings exhibited superior
biocidal functionality with complete inactivation of about 6 logs of Staphylococcus aureus and Escherichia coli O157:H7 within 2–10 min contact time depending on the structure. Moreover, the coatings were quite stable against repeated
laundering so that recharging was not even necessary after 50 washing cycles. Stability of the coatings against ultraviolet
light exposure was studied with a comparison of the amide- and amine-containing N-halamines. 相似文献
954.
Viktor O. Iaroshenko Sajid AliTariq Mahmood Babar Sergii DudkinSatenik Mkrtchyan Nasim Hasan RamaAlexander Villinger Peter Langer 《Tetrahedron letters》2011,52(3):373-376
4-Chloro-3-(trifluoroacetyl)coumarin was synthesized for the first time via direct TMSCl-mediated acylation of 4-hydroxycoumarin with TFAA followed by the treatment with POCl3. The reaction of 4-chloro-3-(trifluoroacetyl)coumarin with commercially available anilines is a two-step method, which affords a set of 7-(trifluoromethyl)-6H-chromeno[4,3-b]quinolin-6-ones in good to excellent yields. 相似文献
955.
Javad Azizian Khadijeh Yadollahzadeh Hasan Tahermansouri Davood Chobfrosh Khoei Akram Sadat Delbari 《合成通讯》2013,43(14):2110-2120
Urea polyfunctional derivatives were successfully synthesized via a one-pot, five-component nucleophilic addition/Ugi reaction sequence. Simplicity, solvent-free conditions, and good yields of products are advantages of this method. 相似文献
956.
Md. Aminul Haque Md. Mahedi Hasan Tamanna Islam Md. Abdur Razzak Nabeel H. Alharthi Abdullah Sindan Mohammad R. Karim Shaik Inayath Basha Md. Abdul Aziz A. J. Saleh Ahammad 《Electroanalysis》2020,32(9):1957-1970
We have prepared activated porous carbon material through simple pyrolysis method from rice husks (rhAC) for sensitive detection of dopamine (DA) and uric acid (UA). The prepared rhAC material was thoroughly characterized using various spectroscopic, microscopic, and electroanalytical techniques. Analysis of the voltammetric data showed that the analytes followed a first order reaction kinetics while following a 2e?/2H+ transfer process. We have discussed the possible oxidation mechanism for the analytes based on the results from our experimental analysis. The rhAC_GCE sensor was tested for interference, reproducibility, and stability. The sensor was also tested to evaluate its applicability in real life. 相似文献
957.
New bis(isatins-thio/carbohydrazones) based on Schiff bases were prepared from terephthalaldehyde biscarbohydrazone and 5-substituted isatins in the presence of a drop of sulfuric acid under reflux in ethanol. Terephthalaldehyde bis(thio/carbohydrazone) was synthesized by the reaction of (thio)/carbohydrazide and terephthalaldehyde in the presence of a few drops of acetic acid under reflux in ethanol. The structures of these synthesized compounds were determined using IR, 1H NMR, and 13C NMR spectroscopy and elemental analysis. The in vitro antioxidant activity of all the compounds was determined by the 1,1-diphenyl-2-picryl hydrazyl (DPPH.) free radical scavenging method. Compound 2 showed the best antioxidant activity. 相似文献
958.
Yakan Hasan Bakır Temel Kan Çavuş M. Serdar Muğlu Halit 《Research on Chemical Intermediates》2020,46(12):5417-5440
Research on Chemical Intermediates - Five new Schiff bases of isatin and its derivatives were prepared from monothiocarbohydrazides and 5-chloro isatin. The chemical structures of the synthesized... 相似文献
959.
Mobina Alimohammady Mansour Jahangiri Farhoush Kiani Hasan Tahermansouri 《Research on Chemical Intermediates》2018,44(1):69-92
Carboxylated multi-walled carbon nanotubes (MWCNTs-COOH) were chemically modified with 3-aminopyrazole (MWCNTs-f) and applied as an efficient adsorbent to mercury and arsenic adsorption from aqueous solutions. The adsorbents were characterized by FT-IR, EDX, FE-SEM, TGA, and BET. The effects of pH, adsorbent dose, and initial ions concentration on the adsorption efficiency and the optimum conditions were investigated by central composite design. The optimum conditions were obtained at pH 7.6–7.9, adsorbent dose 20 mg, and initial ions concentration 20 ppm. So the maximum adsorption efficiencies in these conditions were 80.5 and 72.4% for the removal of Hg(II) and As(III) by MWCNTs-f, respectively. The quadratic model was used for the analysis of variance and indicated that adsorption of metal ions strongly depends on pH. Also, the pseudo-second-order model has been achieved from the adsorption kinetic studies. Furthermore, the experimental data were well fitted to the Langmuir isotherm and the maximum adsorption capacities obtained were 112 and 133 mg g?1 for the adsorption of Hg(II) and As(III) by MWCNTs-f, respectively. Moreover, a thermodynamic study revealed that the adsorption reactions were spontaneous and endothermic with the increase in randomness. In addition, a desorption study showed the favorable regeneration ability of MWCNTs-f even after three adsorption–desorption cycles. Therefore, the MWCNTs-f adsorbent has good potential for the removal of Hg(II) and As(III) pollutants from aqueous solutions. 相似文献
960.
Avcıbaşı Uğur Demiroğlu Hasan Sakarya Serhan Ünak Perihan Tekin Volkan Ateş Buket 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):275-287
Journal of Radioanalytical and Nuclear Chemistry - The aim of this study was to investigate the 131I and 127I labeled linezolid and moxifloxacin effects of minimum inhibitory concentration, and... 相似文献