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81.
Corrosion Inhibition and Adsorption Behavior of Sodium Lauryl Ether Sulfate on L80 Carbon Steel in Acetic Acid Solution and Its Synergism with Ethanol
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Mohamed Abdel Moneim Deyab 《Journal of surfactants and detergents》2015,18(3):405-411
The application of sodium lauryl ether sulfate (SLES) as an anionic surfactant and its synergistic combination with ethanol for inhibition of corrosion of L80 carbon steel in acetic acid solutions were investigated by means of potentiodynamic polarization measurements, scanning electron microscopy (SEM), X‐ray diffraction (XRD), and energy‐dispersive X‐ray (EDX) investigations. The inhibition efficiency increases with an increase in concentration of SLES. The adsorption of SLES on the surface of L80 carbon steel obeys the Freundlich isotherm. SLES acts predominately as an anodic inhibitor. XRD, EDX, and SEM examinations of the electrode surface confirmed the adsorption of SLES on the electrode surface. The addition of ethanol with SLES significantly enhances the inhibition effectiveness and generates a strong synergistic effect. 相似文献
82.
A new polymer nanocomposites of an epoxy resin matrix with randomly dispersed nano‐vanadium sesquioxides (V2O3) in various amounts were prepared. The structure of the nanocomposites were characterized by scanning and transmission electron microscopy (SEM and TEM), X‐ray diffraction, hardness, packing factor, extent of filler reinforcement, glass transition temperature, and sound velocity. The percolation threshold in the conductivity of the composites is lesser than 8 wt % and the dielectric constant can reach as high as 103. The resistivity—temperature curve of the composites shows a positive temperature coefficient (PTC) effect. The thermal stability of the composites was examined in terms of thermal gravimetry and differential scanning calorimetry (TG and DTA) and isothermal resistivity–time check. Because of the interfacial interaction among filler particles and the epoxy matrix, the nanocomposites exhibit higher thermal stability. The current–voltage–temperature curves behave as switching current. The temperature increases linearly with the applied voltage which makes this PTC nanocomposites very useful for temperature probe. Finally, electromagnetic interference shielding effectiveness (SE) values have been calculated and measured for the nanocomposites in the frequency range 1–12 GHz. It is found that the SE properties of the nanocomposite improve with increase in wt % of V2O3. A maximum SE of 42 dB for V20 sample at 12 GHz has been achieved. These nanocomposites are potentially useful in suppression of electromagnetic interference and reduction of radar signature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
83.
A. A. El-Neshawy A. M. Rabie A. A. Abdel Baky M. M. Nasr E. A. Emara 《Molecular nutrition & food research》1985,29(3):255-267
Trials were carried out to produce Ras cheese of good quality without the use of starter. Cheese was made from pasteurized cow's milk acidified with lactic acid or citric acid to pH 5.8 alone or coupled with mixing the curd with glucono δ lactone (4.5 g/kg curd). Control cheese was made from milk ripened with a starter culture of S. lactis. Resultant cheeses showed poor body and texture, weak flavour intensity and low levels of soluble nitrogen compounds and free volatile fatty acids. Incorporation into the cheese curd of mixtures containing Fromase 100 (fungal protease) and Piccantase B (fungal lipase) or Fromase 100 and Capalase K (animal lipase) enhanced flavour intensity, improved body characteristics and accelerated the formation of both soluble nitrogen compounds and free volatile fatty acids. The organoleptic properties of the experimental cheeses with added enzymes were comparable to those of the control cheese. 相似文献
84.
85.
Mahmoud M. Elghoul Doaa M. Zaghloul Kareem Morsy Mohamed M. A. Abumandour 《Microscopy research and technique》2022,85(6):2076-2082
Testicular parenchyma is split into lobules, each lobule contains convoluted seminiferous tubules surrounded by myoid cells and the interstitial tissue contains groups of Leydig cells. The seminiferous tubules are lined by two groups of cells the first one is the spermatogenic cells and the second one is Sertoli cells. 相似文献
86.
Kavita Mathur David Hinks Abdel‐Fattah M. Seyam Robert Alan Donaldson 《Color research and application》2009,34(3):225-232
Jacquard woven fabrics are made from colored yarns and different weaves for designing complex pictorial and other patterning effects. The final visualized color effect is the result of assigning weave designs to different areas of the pattern to be created. The current practice in creating Jacquard woven fabric designs is to produce many samples in a trial‐and‐error attempt to match artwork colors. An ability to simulate accurately the appearance of a design prior to manufacture is highly desirable to reduce trial‐and‐error sample production. No automated accurate digital color methodology is yet available to assist designers in matching the patterned woven fabric to the desired artwork. To achieve this, we developed a geometrical model to predict the color contribution of each yarn on the face of the fabric. The geometrical model combined with a Kubelka‐Munk based color mixing model allowed the prediction of the reflectance properties of the final color for a given design. We compared the predicted and experimental values of the reflectance properties for a range of fabrics using the same geometric model with three separate color mixing models. The geometrical model combined with a log‐based color mixing model produced reasonable agreement between predicted and measured ΔEab, with an average ΔEab of approximately five. © 2009 Wiley Periodicals, Inc. Col Res Appl, 34, 225–232, 2009 相似文献
87.
88.
M. Abdel Monem W. L. Lindsay R. Sommer J. Ryan 《Nutrient Cycling in Agroecosystems》2010,86(3):357-366
Fertilizer-applied Nitrogen (N) may be lost from the soil by various mechanisms, i.e., runoff, leaching, denitrification,
and volatilization. The latter process is of primary concern in calcareous soils of arid and semi-arid regions, especially
when urea is used. In this field study from northern Syria, urea alone, urea with either an incorporated urease inhibitor,
phenylphosphorodiamidate, or an experimental bran-wax coating were evaluated on wheat for two cropping seasons at two experimental
stations with varying average seasonal rainfall (340 mm, 270 mm). Loss of N was assessed with 15N by mass balance, i.e., the amount of N applied minus the crop N uptake and N remaining in the soil. Crop yields and N uptake
were related to seasonal rainfall. Losses of N, apparently as volatilized NH3, were relatively low at both sites, i.e., 11–18%. However, compared to the unmodified urea, neither the incorporated urease
inhibitor nor the bran-wax coating had any effect on yields, N uptake or N loss. While urea hydrolysis is normally rapid,
it may be delayed by dry conditions at the soil surface; similarly, unusually cold periods may delay nitrification following
hydrolysis. Thus, under the cool-season conditions of rainfed cropping in the Middle East, efficient use of urea is not likely
to be achieved by modification of the urea but by conventional management practices that ensure pre-plant soil incorporation
or topdressing during early spring rains. 相似文献
89.
Staples Julie K.; Abdel Atti Jamil Ahmed; Gordon James S. 《Canadian Metallurgical Quarterly》2011,18(3):246
A mind-body skills group program was evaluated to determine its effects on symptoms of posttraumatic stress disorder (PTSD) and depression, and on hopelessness in children and adolescents in Gaza. The 10-session mind-body skills groups included meditation, guided imagery, breathing techniques, autogenic training, biofeedback, genograms, and self-expression through words, drawings, and movement. Data were analyzed from 129 children and adolescents meeting criteria for PTSD. Significant improvements in PTSD and depression symptoms and a significant decrease in a sense of hopelessness were observed immediately following participation in the program. At 7-month follow-up, the improvements in the total PTSD and depression scores were largely maintained and the decreased sense of hopelessness was fully maintained despite ongoing violent conflict and economic hardship. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
90.
2,7‐Di‐tert‐butylpyrene was oxidized to 2,7‐di‐tert‐butylpyrene‐4,5,9,10‐tetraone. The latter through condensation reaction with vicinal diamine such as diaminomaleodinitrile afforded heterocyclic monomer, 2,7‐di‐tert‐butyl pyrene[4,5][9,10]bis(2,3‐pyrazine‐5,6‐dinitrile), which was cyclotetramerized to the corresponding 2H‐ and metal‐pyrazinoporphyrazine‐based network polymers (2H‐PyzPz and M‐PyzPz, M = Co, Ni, Zn, or Cu). Elemental analytical results, Infrared, and NMR spectral data of the new prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents of the synthesized polymers proved to be of high molecular masses, which confirm the efficiency of tetramerization polymerization and complexation reactions. Dielectric permittivity, ε′, loss tangent, tan δ, and ac conductivity, σac(ω), of 2H‐PyzPz and M‐PyzPz films were studied as a function of temperature and frequency. It was found that dielectric permittivity, ε′, decreases with the increase of frequency and increases with the increase in temperature. Ac conductivity, σac(ω), is found to vary as Bωs and the frequency exponent, s, is less than unity around room temperature indicating a dominant hopping process. On the other hand, σac(T) of all samples is thermally activated with low activation energies. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011. 相似文献