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71.
AbstractIn this work, the coupled NLSE is studied that appears in a cascased system. Exact solutions of this coupled system acquire by using Jacobi elliptic functions. The presented system will be studied with two forms of nonlinearity. The forms are kerr law and power law. Dark, bright, singular solitons and Jacobi elliptic solutions will be acquired. We present constraint conditions for the existence of obtained solitons. Our obtained solitons will be controlled by changing the diffraction coefficients. 相似文献
72.
İbrahim Uslu Arda Aytimur Mustafa Kemal Öztürk Serhat Koçyiğit 《Ceramics International》2012,38(6):4943-4951
In this study, a new method to synthesize neodymium doped ceria ceramic nanopowders by the electrospinning of the hybrid polymers solution of their composite precursor was put forward. Calcined and sintered nanopowders were characterized by FT-IR, XRD, BET, SEM, and AFM techniques. According to the XRD analysis, the obtained powders are single phase and independent of the dopant concentration in the range investigated. The crystallite sizes were calculated using Scherrer equation. Moreover, lattice parameters, dislocation densities and microstrain values were calculated. BET results show that the increase of the neodymium doped content decrease the surface area of the composite powders, confirming the highly ordered micro and mesostructure. SEM and AFM results show that the samples have spherical grains. According to the surface roughness measurements, the increase in the amount of neodymium and the decrease in the amount of cerium decreased the surface roughness. 相似文献
73.
Ebru Mensur Alkoy Canan Dagdeviren Melih Papila 《Journal of the American Ceramic Society》2009,92(11):2566-2570
Lead zirconate titanate (PZT) nanofibers are obtained by electrospinning a sol–gel based solution and polyvinyl pyrrolidone (PVP) polymer, and by subsequent sintering of the electrospun precursor fibers. The average diameter of the precursor PZT/PVP green fibers has increased with the aging of the precursor solution along with an increase in the viscosity. Bead-free uniform green PZT/PVP fibers were collected at about an ∼230 nm average fiber diameter using a 28 wt% PVP ratio solution with a viscosity of 290 mPa. Shrinkage of 40% was recorded on the fiber diameter after sintering. The X-ray diffraction pattern of the annealed PZT fibers exhibits no preferred orientation and a perovskite phase. Preparation of 3–3 nanocomposites by the infusion of polyvinylester into the nanofiber mat facilitates successful handling of the fragile mats and enables measurements of the dielectric properties. The dielectric constant of the PZT/polyvinylester nanocomposite of about 10% fiber volume fraction was found to be fairly stable and vary from 72 to 62 within the measurement range. The dielectric loss of the composite is below 0.08 at low frequencies and reaches a stable value of 0.04 for most of the measured frequencies. 相似文献
74.
Besides the new developments in agricultural technology, intensive use of pesticides poses a great environmental hazard. The unthinking use of pesticides leads to contamination of air, water and soil. There are several pesticide risk indicator models available in the literature to assess pesticide impacts on the applicator and the ecosystem which is an important issue. This paper refers to an application of a pesticide risk indicator model, called Environmental Impact Quotient (EIQ) which was developed to measure the environmental impacts of pesticide active ingredients used in vegetable and fruit production. The application site is the Kumluca region of Turkey, which is well known for its intensive agricultural activities. As the first step in the model application, EIQ values have been calculated for 35 commonly used pesticides in Kumluca. EIO values were then turned into EIQ field use rating results based on the active ingredient percent and application rate. Furthermore, some pesticide management scenarios were evaluated to select the least detrimental pesticide by comparing EIO model results. The EIO model is an easily applied and very helpful tool for pest management practitioners and agricultural specialists. It can be used efficiently to compare different agricultural pest management strategies or programs. 相似文献
75.
This study investigated architects' and nonarchitects' evaluative and cognitive judgments of color on building exteriors. Thirty architects and 30 high school teachers living in Izmir, Turkey participated in the study. The experiment had two phases. First, participants viewed eight images, in which the color of a building exterior was manipulated with hues selected from HSB (hue, saturation, and brightness) color space. Participants were then asked to rate each image on 7‐point semantic differential scales measuring preference (like–dislike), arousal (arousing–sleepy), naturalness (natural–artificial), and relaxation (relaxing–distressing). Second, participants viewed the same building in nine saturation and lightness levels for each hue and picked the most preferred lightness and saturation level for each hue. Findings showed that for a building exterior: (1) yellow and blue were the most liked colors, (2) some hues were rated as more arousing, more natural, and more relaxing over the others, (3) gender had an effect on color preference and semantic ratings of naturalness and relaxation, (4) architects and nonarchitects differed in their color preference and semantic ratings of arousal and naturalness, and (5) full bright and moderate to low saturated colors and full saturated and moderate to high bright colors were preferred more. The results have practical implications for architects and urban designers. A successful coloration of a building exterior may increase its use frequency and economical value. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 395–405, 2008 相似文献
76.
77.
Berksoy-Yavuz Ayse Kaya Mustafa Yunus Avcı Tubanur Cakırbas Gizem Menşur Ebru 《Journal of Materials Science: Materials in Electronics》2022,33(5):2336-2349
Journal of Materials Science: Materials in Electronics - The effect of crystallographic texture on the properties of 0.94(Na0.5Bi0.5TiO3)–0.06BaTiO3 (0.94NBT–0.06BT) ceramics were... 相似文献
78.
79.
Emre Çinar Serhat Koçyiğit Arda Aytimur İbrahim Uslu Ahmet Akdemir 《Metallurgical and Materials Transactions A》2014,45(9):3929-3937
In this study, the boron-doped barium-stabilized bismuth cobalt oxide thermoelectric nanocrystalline ceramic powders were produced by the polymeric precursor technique. The powders were characterized by X-ray diffraction, scanning electron microscopy, and the physical properties measurement system. The X-ray diffraction results showed that these patterns have mixture of two phases as face-centered cubic and body-centered cubic. Values of the crystallite size, the dislocation density, and the microstrain were calculated by the Scherrer equation. According to these values, the crystallite size decreased from 60 to 51 nm with the boron addition in the boron-undoped and boron-doped samples, respectively. The scanning electron microscope results showed that nanograins are rarely seen in the boron-undoped samples, but nanograins turn into needle-like and layered structures with boron addition. The diameters distribution of nanofibers was calculated. The average diameter of the boron-doped sample is smaller than the boron-undoped sample. The physical properties measurement system values showed that the electrical and thermal conductivity, the Seebeck coefficient, and the figure of merit increased with the temperature rise for both samples. The boron-doping effect increased the electrical and thermal conductivity, decreased the Seebeck coefficient, and decreased the figure of merit. 相似文献
80.
Instruments and Experimental Techniques - Currently, plastic (organic) scintillators are using in new type positron emission tomography (PET) devices such as J-PET. But, these type scintillators... 相似文献