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991.
A variety of surface active compounds were synthesized by the quaternization of some straight chain amide derivatives with triethylamine or pyridine. Their structure FT-IR and 1H-NMR spectra were recorded. In addition their physical properties and corrosion prevention efficiencies were investigated. All compounds were tested with steel coupons in acidic media by the gravimetric method. As acidic media 1.5 M HCl and 1.5 M H2SO4 were used and the corrosion inhibition tests fulfilled at room temperature for 24 h. Almost all prepared cationic surfactants showed efficient inhibition around their critical micelle concentrations. The effects of HCl concentration on corrosion inhibition of some synthesized compounds were also investigated. The corrosion tests were supported by contact angle measurements. 相似文献
992.
993.
Nasanjargal Purev Ladislav Burgert Petr Prichystal Radim Hrdina Jiri Kühn Michal Cerny Jamyan Oyuntulkhuur 《Coloration Technology》2013,129(6):412-417
CI Acid Black 210 was microencapsulated into liposomic systems, and the effects of the microencapsulation on dyebath exhaustion, depth of shade, colour fastness properties and through‐dyeing of chrome‐tanned leather were studied. In comparison with the original dyestuff form, the microencapsulated dye showed a deeper shade and a greater depth of through‐dyeing. Exhaustion and colour fastness values were the same. 相似文献
994.
Tilo Welker Thomas Geiling Heike Bartsch Jens Müller 《International Journal of Applied Ceramic Technology》2013,10(3):405-412
Low‐temperature co‐fired ceramics (LTCC) enable the fabrication of microfluidic elements such as channels and embedded cavities in electrical devices. Hence, LTCC facilitate the realization of complex and integrated microfluidic devices. Examples can be applied in many areas like reaction chambers for synthesis of chemical compounds. However, for many applications it is necessary to have an optically transparent interface to the surroundings. The integration of optical windows in LTCC opens up a wide field of new and innovative applications such as the observation of chemiluminescent reactions. These chemical reactions emit electromagnetic radiation and thus offer a method for noninvasive detection. Thin glasses (≤500 μm) were bonded by thermocompression onto a LTCC substrate. As the bonding agent, a glass frit paste was used. Borosilicate glasses, fused silica as well as silicon were successfully bonded onto LTCC. To join materials with a large coefficient of thermal expansion mismatch (i.e., fused silica and LTCC), it is necessary to limit the heat input to the bond interface. Therefore, a heating structure was integrated into the LTCC substrate beneath the bond interface. This bonding process provides a gas‐tight optical port with a high bond strength. 相似文献
995.
Mateus Carlesso Renan Giacomelli Stefan Günther Dietmar Koch Stephen Kroll Stefan Odenbach Kurosch Rezwan 《Journal of the American Ceramic Society》2013,96(3):710-718
We present an interesting processing route for obtaining alumina/mullite‐based ceramics with controlled porosity and airflow resistance leading to promising microstructures for application as sound absorbers. The use of ceramic materials aims for potential applications where high temperatures or corrosive atmospheres are predominant, e.g., in combustion chambers of gas turbines. For the production of the porous ceramics we combined freeze gelation and sacrificial templating processes to produce near‐net‐shaped parts with low shrinkage (<3%) based on environmental‐friendly and low cost conditions. The obtained microstructure presents a bimodal pore size distribution, with small pores derived from the freeze gelation process (~30 μm) connecting large pores (2–5 mm diameter) originated from the expanded polystyrene template particles. These connections, called “windows” in this study, show a significant impact on the sound absorption properties, allowing the pressure diffusion effect to take place, resulting in a significant improvement of the sound absorption coefficient. By varying the template particle content and the slurry solid content, it is possible to control the sound absorption behavior at different frequencies of the open‐celled ceramics. These ceramics feature a high open porosity, from 77% to 82%, combined with sufficient compressive strength ranging from 0.27 to 0.68 MPa and sound absorption coefficients of 0.30–0.99, representing a highly promising combination of properties for noise control and reduction at corrosive environments and high temperatures. 相似文献
996.
Ayça Bal Tülin Banu İyim Saadet Özgümüş 《Polymer-Plastics Technology and Engineering》2013,52(10):990-995
Waterborne acrylic emulsion was obtained by using methyl methacrylate, ethyl and butyl acrylate monomers. Emulsions containing nanoparticles were prepared by blending the stable dispersions containing SiO2 or MMT nanoparticles. The films were prepared from emulsions and coating tests were applied. The physical properties of prepared emulsions are better than the commercial emulsions. The addition of the nanoparticles especially SiO2 have positive effect on the resistance to environmental conditions of emulsions. Waterborne acrylic emulsions containing nanoparticles prepared in this study can be used in the manufacturing of the semi-lustrous emulsion type nano paint with low cost, high performance and environmentally friendly. 相似文献
997.
Lemi Türker 《Polycyclic Aromatic Compounds》2013,33(3):213-219
Semi-empirical molecular orbital treatment at the level of AM1 type has been performed on Hückel type silacyclacenes having arenoid rings (R) of 2-9. The first and second type cryptoannulenic effects are defined. 相似文献
998.
M. Hamdi Karagöz Özlem Selçuk Zorer Zülfiye İlter 《Polymer-Plastics Technology and Engineering》2013,52(7):785-789
In this study, physical and thermodynamic properties of poly(2-phenyl-1,3-dioxolane-4-yl-methyl-methacrylate-co-styrene) (PDMMA-ST) were investigated by using inverse gas chromatography. Two groups of solvents with different chemical natures and polarities were used to obtain information about PDMMA-ST-solvent interactions: alcohols and alkanes. The specific retention volume (Vg 0), the sorption enthalpy (ΔH1 S), sorption free energy (ΔG1 S), sorption entropy (ΔS1 S), the weight fraction activity coefficients of solute probes at infinite dilution (Ω 1 ∞), and Flory-Huggins interaction parameters (χ 12 ∞) between polymer and solvents were determined for the interactions of PDMMA-ST with alcohols and alkanes by inverse gas chromatography in the temperature range of 333–473 K. Also, the solubility parameters of PDMMA-ST at infinite dilution were found by plotting the graph of [(δ 1 2/RT) - χ 12 ∞/V1] versus solubility parameters, δ 1, of probes. 相似文献
999.
Münir Taşdemir 《Polymer-Plastics Technology and Engineering》2013,52(11):1207-1211
This article reports on an experimental study of the physical and mechanical properties of Polystyrene (PS) and Fe-PS polymer composites containing 5, 10, and 15 vol.% of Fe powder. After mixing Fe powder and PS in a twin-screw extruder, an injection-molding machine was used to prepare unfilled PS and Fe-PS polymer composite samples. After that, the material properties were experimentally determined for each sample. The investigated material properties included the modulus of elasticity, yield and tensile strength, % elongation, Izod impact strength (notched), hardness (Shore D), melt flow index (MFI), heat deflection temperature (HDT), Vicat softening point, and glass transition temperature (T g ). The results indicated that, compared to the unfilled PS, an addition of Fe into PS decreases the yield and tensile strength, % elongation, and Izod impact strength. Furthermore, it was determined that the Fe particles increase the modulus of elasticity, hardness, MFI, Vicat softening point, and HDT values. 相似文献
1000.
Erol Erbay Tülidotn Bidotlgidotç Metidotn Karali Ö. Tunç Savaşçi 《Polymer-Plastics Technology and Engineering》2013,52(7-8):589-605
Effects of polymerization parameters are studied to better understand interactions between parameters in stirred-tank polymerization reactors and to derive a regression model correlating polymer particle size and particle-size distribution with agitator speed, agitator diameter, tricalcium phosphate, dodecyl benzene sodium sulfonate concentrations, and mass cycle period. The derived equations give way to prediction of the polymerization conditions in order to obtain desired particle size and particle-size distributions which covers particle sizes between 0.3 and 5 mm. The roles of some other parameters and limiting agitation parameters are also investigated. 相似文献