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1.
Hudaverdi Turker Akyildiz Ozge 《Bulletin of Engineering Geology and the Environment》2019,78(1):177-187
Bulletin of Engineering Geology and the Environment - A novel classification approach was proposed for prediction of flyrock throw distance based on the site measurements performed in a sandstone... 相似文献
2.
Nanocomposites consisting of thermoplastic polyurethane–urea (TPU) and silica nanoparticles of various size and filler loadings were prepared by solution blending and extensively characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), thermal analysis, tensile tests, and nanoindentation. TPU copolymer was based on a cycloaliphatic diisocyanate and poly(tetramethylene oxide) (PTMO-2000) soft segments and had urea hard segment content of 20% by weight. TPU/silica nanocomposites using silica particles of different size (29, 74 and 215 nm) and at different loadings (1, 5, 10, 20 and 40 wt. %) were prepared and characterized. Solution blending using isopropyl alcohol resulted in even distribution of silica nanoparticles in the polyurethane–urea matrix. FTIR spectroscopy indicated strong interactions between silica particles and polyether segments. Incorporation of silica nanoparticles of smaller size led to higher modulus and tensile strength of the nanocomposites, and elastomeric properties were retained. Increased filler content of up to about 20 wt. % resulted in materials with higher elastic moduli and tensile strength while the glass transition temperature remained the same. The fracture toughness increased relative to neat TPU regardless of the silica particle size. Improvements in tensile properties of the nanocomposites, particularly at intermediate silica loading levels and smaller particle size, are attributed to the interactions between the surface of silica nanoparticles and ether linkages of the polyether segments of the copolymers. 相似文献
3.
Sacide Alsoy Altinkaya Ozge TopcuogluYilmaz Yurekli Devrim Balkose 《Progress in Organic Coatings》2010
Diffusion coefficients and sorption isotherms of water in waterborne acrylic paint films and in the pure binder of the paints have been measured by gravimetric sorption. Solubility of water was found to enhance with the increased binder content in the paint films while the diffusivity of water decreased significantly. Sorption isotherms in the paint and pure copolymer films were correlated with the Flory Huggins theory and ENSIC model, respectively. Fickian diffusion was observed in both types of films and the kinetic data were best correlated with a numerical model which takes into account the concentration dependency of the diffusion coefficient and the dimensional change of the film due to sorption. It was concluded that the utilization of a simplified analytical solution may lead to significant errors in the estimation of diffusivities. 相似文献
4.
In this study, the removal of copper(II) and cadmium(II) ions from aqueous solutions by biosorption onto pine cone was studied. Variables that affect the biosorption process such as pH, biosorbent dosage, initial metal ion concentration, contact time and temperature of solution were optimized. Experimental data were fitted to Langmuir, Freundlich, Dubinin Radushkevich and Temkin isotherm models to investigate the equilibrium isotherms. Pseudo-first-order, pseudo-second-order and intraparticle diffusion kinetic models were used to determine the biosorption mechanism. The thermodynamics of biosorption were studied for predicting the nature of biosorption. Experimental results showed that pine cone could be evaluated as an alternative precursor for removal of heavy metal ions from aqueous solutions, due to its high biosorption capacity, availability, and low cost. 相似文献
5.
Semin Ozge Keskin Serpil Oztürk Serpil Sahin Hamit Koksel Gülüm Sumnu 《European Food Research and Technology》2005,220(5-6):546-551
The effects of halogen lamp–microwave combination baking on the quality of cookies in terms of texture, color and spread ratio were studied. In addition, gelatinization and pasting properties of cookies baked in different ovens were assessed by using a Rapid Visco Analyzer. The hardness values of the cookies increased with increasing baking time and/or halogen power. The microwave power also contributed to cookie hardness. The lightness values of the cookies decreased, while the a* and E values increased linearly during baking at different halogen lamp and microwave powers. The spread ratio of conventionally baked cookies was significantly lower than that of the other cookies. Halogen lamp power, microwave power and baking time were found to have a significant effect on the spread ratio of the cookies. The moisture contents of the cookies decreased during baking as the halogen lamp and/or the microwave power level increased. The best baking condition in a halogen lamp–microwave combination oven to produce cookies having similar quality parameters as conventionally baked ones was baking at 70% halogen lamp and 20% microwave power levels for 5.5 min. The baking time of these cookies is half of that required in conventional baking. 相似文献
6.
In this study an agricultural residue, sesame stalk, was evaluated for the removal of Ni(II) and Zn(II) metal ions from aqueous solutions. Biosorption studies were carried out at different pH, biosorbent dosage, initial metal ion concentrations, contact time, and solution temperature to determine the optimum conditions. The experimental data were modeled by Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models. Langmuir model resulted in the best fit of the biosorption data. The pseudo-first-order and pseudo-second-order kinetic models were used to describe the kinetic data and to evaluate rate constants. The best correlation was provided by the second-order kinetic model. The thermodynamic parameters such as ΔG°, ΔH° and ΔS° were calculated for predicting the nature of adsorption. The experimental results showed that sesame stalk can be used as an effective and low-cost biosorbent precursor for the removal of heavy metal ions from aqueous solutions. 相似文献
7.
Ozge Sakiyan Gulum Sumnu Serpil Sahin Venkatesh Meda 《The Journal of microwave power and electromagnetic energy》2007,41(1):20-26
The aim of this study was to determine the effect of different formulations on color and textural characteristics of different cakes during baking in microwave and near infrared-microwave combination ovens. For comparison, cakes were also baked in conventional ovens. Color and hardness for both types of baking schemes were found to be dependent on formulation. Cakes containing Simplesse, a fat replacer consisting mostly of whey protein, baked in microwave and near infrared-microwave combination ovens were found to be the firmest cakes. 相似文献
8.
Mehmet M. Kose Ozge Karslioglu 《The Structural Design of Tall and Special Buildings》2009,18(8):907-920
In this study, the effects of infill walls to the response of a selected building under earthquake loading were investigated. Although various suggestions have been offered, designers usually neglect the effect of infill walls on building behaviour when designing a building. In this study, the effects of infill walls on a building, which consists of two storeys of basement, one storey of ground floor, one storey of mezzanine floor and 10 storeys of flats, were investigated. Three‐dimensional models of the building with and without infill walls were modelled in SAP2000. Then, nonlinear time history analysis was performed on the models with and without infill walls. Infill walls were modelled both as mass and structural elements. The results of two analyses were compared. Consequently, the effect of infill walls on the behaviour of buildings such as period, maximum roof displacement, base columns end‐forces and soft‐storey formation coefficient was determined. Addition of infill wall to the structures caused changes in maximum roof displacement, modal periods, maximum base column end‐forces, shear force and soft‐storey formation coefficient. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
9.
Banu Kocaaga Ozge Kurkcuoglu Melkon Tatlier Saime Batirel F. Seniha Guner 《应用聚合物科学杂志》2019,136(24):47640
This study presents the design of novel hydrogel films, based on low-methoxyl (LM) pectin and NaA- or ZnA-zeolite particles, to serve as wound dressing materials with controlled drug delivery properties. We studied the effects of the preparation method of hydrogels, the amounts of crosslinker, drug and zeolite, and the type of cation in zeolites on the drug release mechanisms from the hydrogels. Ionic strengths of both film and external medium dictated the drug release behavior of the films, while the other parameters also played essential roles. NaA-zeolite hydrogels prepared using membrane diffusion controlled system, could reach a drug release ratio of 86% within 5 h. The drug-free hydrogels displayed no cytotoxicity while supporting cell proliferation and migration. Our cost-effective LM pectin–zeolite hydrogels promise to be effective wound dressing materials with controlled drug delivery ability, transparency, good swelling properties, ability to hold fluids, good oxygen transmission rate, and biocompatibility. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47640. 相似文献
10.
Hadiseh Taheri Mehmet Altay Unal Melike Sevim Cansu Gurcan Okan Ekim Ahmet Ceylan Zois Syrgiannis Konstantinos C. Christoforidis Susanna Bosi Ozge Ozgen Manuel Jos Gmez Mine Turktas Erken igdem Soydal Zafer Erolu Ceylan Verda Bitirim Umut Cagin Fikret Ar Asuman Ozen Ozlem Kuuk Lucia Gemma Delogu Maurizio Prato
nder Metin Aelya Yilmazer 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(10)