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11.
Hacer Bilgin Ellidokuzoğlu & Serkan Demiriz 《分析论及其应用》2021,37(4):557-571
Başar and Braha [1], introduced the sequence spaces $\breve{\ell}_\infty$, $\breve{c}$ and $\breve{c}_0$ of Euler-Cesáro bounded, convergent and null difference sequences and studied their some properties. Then, in [2], we introduced the sequence spaces ${[\ell_\infty]}_{e.r}, {[c]}_{e.r}$ and ${[c_0]}_{e.r}$ of Euler-Riesz bounded, convergent and null difference sequences by using the composition of the Euler mean $E_1$ and Riesz mean $R_q$ with backward difference operator $\Delta$. The main purpose of this study is to introduce the sequence space ${[\ell_p]}_{e.r}$ of Euler-Riesz $p-$absolutely convergent series, where $1 \leq p <\infty$, difference sequences by using the composition of the Euler mean $E_1$ and Riesz mean $R_q$ with backward difference operator $\Delta$. Furthermore, the inclusion $\ell_p\subset{[\ell_p]}_{e.r}$ hold, the basis of the sequence space ${[\ell_p]}_{e.r}$ is constructed and $\alpha-$, $\beta-$ and $\gamma-$duals of the space are determined. Finally, the classes of matrix transformations from the ${[\ell_p]}_{e.r}$ Euler-Riesz difference sequence space to the spaces $\ell_\infty, c$ and $c_0$ are characterized. We devote the final section of the paper to examine some geometric properties of the space ${[\ell_p]}_{e.r}$. 相似文献
12.
Fluorine (F) incorporated polycrystalline SnO2 films have been deposited onto glass substrates by ultrasonic spray pyrolysis technique. To possess information about the electrical properties of all films, their electrical conductivities were investigated depending on the temperature, and their activation and trap energies were analyzed. The crystalline structure, surface properties and elemental analysis of the SnO2 films were examined to determine the effect of the F element. After all investigations, it was concluded that each fluorine incorporation rate has a different and important effect on the physical properties, and SnO2:F (3 at%) films were found to be the most promising sample for energy conversion devices, especially as conducting electrode in solar cells with its improved structural and electrical properties as compared to others. 相似文献
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Carbon fiber (CF)‐based WO3/TiO2 composite catalysts (WO3/TiO2/CF) were successfully synthesized by solvothermal method. The catalysts were characterized by XPS, SEM, BET, XRD, FTIR, Raman and UV–Vis. The analyses confirmed the WO3/TiO2 nanoparticles with high crystallinity deposited on the carbon structure. The photocatalytic degradation of Orange II azo dye under UV and sunlight illumination with the synthesized catalyst was explored. The composite catalyst displayed high performance (85%) for Orange II degradation while that of for WO3/TiO2 was found as 76%. The effects of CF amount, solution pH, initial dye concentration and catalyst dose on photocatalytic performance were studied. It was found that the degradation efficiency increased from 68% to 90% with the increasing CF amount from 3 wt% to 5 wt%, while the further increase in CF amount (7–10 wt%) decreased the photodegradation due to the blocking the active sites of WO3/TiO2. The enhanced photocatalytic efficiency was mainly attributed to the electrical properties of the CF and reduced bandgap. 相似文献
15.
Adsorption characteristics of herbicide 4-chloro-2-methylphenoxyacetic acid (MCPA) have been evaluated using bituminous shale
(BS) as a model adsorbent-containing solid organic matter in a mineral matrix. The adsorption of MCPA on BS has been studied
with varying concentration, temperature, pH and contact time, using batch technique. Adsorption ability of BS increases with
increasing temperature and decreasing pH in the studied concentration range of (0.6–4.0) × 10−4 M. Theoretical curves calculated from Freundlich, Dubinin-Radushkevich (D-R), Langmuir and Temkin isotherm equations show
a two-step isotherm shape. The results could be explained by assuming the presence of two-type sites with different affinity
on adsorbent surface. Adsorption process is endothermic and entropy controlled at the first stage, and exothermic and enthalpy
controlled at the second stage. The mechanism proposed based on surface ionization and complexation model is consistent with
the pH dependent experimental results. Kinetic data fit well to both Paterson’s and Nernst Planck model based on homogeneous
solid phase diffusion (HSPD). The values of particle diffusion coefficients (D
p
) predicted from both models are comparable each other and independent of temperature and concentration.
相似文献
16.
Dr. Artur Ciesielski Jürgen Weippert Dr. Artur Böttcher Yuyoung Shin Georgian Melinte Prof. Dr. Ovidiu Ersen Dr. Cinzia Casiraghi Prof. Dr. Xinliang Feng Prof. Dr. Klaus Müllen Prof. Dr. Manfred M. Kappes Prof. Dr. Paolo Samorì Dr. Marco Cecchini 《Chemphyschem》2016,17(3):352-357
Providing a quantitative understanding of the thermodynamics involved in molecular adsorption and self‐assembly at a nanostructured carbon material is of fundamental importance and finds outstanding applications in the graphene era. Here, we study the effect of edge perchlorination of coronene, which is a prototypical polyaromatic hydrocarbon, on the binding affinity for the basal planes of graphite. First, by comparing the desorption barrier of hydrogenated versus perchlorinated coronene measured by temperature‐programmed desorption, we quantify the enhancement of the strength of physisorption at the single‐molecule level though chlorine substitution. Then, by a thermodynamic analysis of the corresponding monolayers based on force‐field calculations and statistical mechanics, we show that perchlorination decreases the free energy of self‐assembly, not only enthalpically (by enhancing the strength of surface binding), but also entropically (by decreasing the surface concentration). The functional advantage of a chemically modulated 2D self‐assembly is demonstrated in the context of the molecule‐assisted liquid‐phase exfoliation of graphite into graphene. 相似文献
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Ersen Beyatl? Solmaz Naghizadeh Adnan Kurt Alphan Sennaroglu 《Applied physics. B, Lasers and optics》2012,109(2):221-225
We report a low-threshold continuous-wave Tm:YAG laser that can be excited near 785?nm with low-cost, single-mode AlGaAs laser diodes. Low-threshold operation was achieved using a tightly focused, astigmatically compensated x-cavity containing a 2-mm-thick Tm:YAG crystal with 5?% Tm3+ concentration. Two linearly polarized single-mode diodes operating at 785.8?nm were polarization coupled to end pump the resonator. With a 6?% output coupler, as high as 32?mW of output power could be obtained at 2016?nm with 184?mW of incident pump power. The output could be further tuned in the 1935?C2035?nm range. Slope efficiency measurements indicated that cross-relaxation was very effective at this doping level. With a 2?% output coupler, lasing could be obtained with as low as 32.3?mW of pump power. In the limit of vanishing output coupling, the incident threshold pump power could be reduced to as low as 25?mW. To our knowledge, this is among the lowest lasing thresholds reported to date for continuous-wave, room-temperature thulium lasers. 相似文献
18.
Ilknur Babahan Ali Özmen Mehran Aksel Mehmet Dincer Bilgin Rukiye Gumusada Muhammet Emin Gunay Fatih Eyduran 《应用有机金属化学》2020,34(7):e5632
In this study, a novel bidentate ligand containing oxime, hydrazone, and indole moieties and its BF2+-bridged transition metal complexes [Ni(II), Cu(II), and Co(II)] were synthesized and their cytotoxic activities against prostate and breast cancer cells were investigated. The vic-dioxime ligand bearing indole–hydrazone side groups was synthesized by reacting antiglyoximehydrazine (GH2) with 3-methoxy indole. The ligand forms mononuclear complexes with a metal-to-ligand ratio of 1:2 with M = Co(II)(H2O)2, Ni(II), and Cu(II). These metal complexes were then reacted with BF3(C2H5)2O to obtain BF2+-bridged transition metal complexes. The Co(II) complex of the ligand is proposed to be octahedral with water molecules as axial ligands, whereas the Ni(II) and Cu(II) complexes are proposed to be square planar. Spectral studies showed that the ligand bonded to the metal ion in a neutral bidentate fashion through the azomethine nitrogen atom and the imine oxime group. Structural assignments are supported by a combination of 1H nuclear magnetic resonance (NMR), 13C NMR, Fourier-transform infrared, LC/MS, elemental analyses, and magnetic susceptibility testing. For determining the cytotoxic effects of the novel anticancer products, cancer cells were cultured. The antiproliferative effects were determined using the MCF-7 breast cancer and PC-3 prostate cancer cell lines. The antiproliferative effects of the products were analyzed and their apoptotic or necrotic effects were determined with the Hoechst/propidium iodide double staining method in both cancer cell lines. Paclitaxel was used as the positive control (1 μm ). The results indicated that the newly synthesized compounds are effective on both cell lines between concentrations of 5 and 40 μm and show their effects by apoptotic mechanisms. Besides, these products were found to be more effective on the MCF-7 cell line. The cytotoxic efficiency of the newly synthesized products was more than that of paclitaxel (depending on concentration), which is a chemotherapeutic agent used in cancer therapy. 相似文献
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We present an extremely simple and inexpensive way to obtain controlled-size and density Co metallic particles on Si(1 1 1) using electrodeposition. When unpatterned substrates are used, the particle density and size can be controlled by adjusting the pulse frequency and the total deposition time. Randomly arranged cobalt particles with diameters of few tens of nanometres are obtained for short deposition times. Continuing the deposition, the particle size and density can be increased until coalescence. Magnetic force microscopy images show magnetically coupled/uncoupled particles depending on the size and distance between them. For small decoupled particles, no in-plane uniaxial anisotropy is found, in agreement with transmission electron microscopy observations which show randomly oriented single crystal particles. As the particle coalescence increases, the in-plane anisotropy evaluated from magnetization loops increases as well. When deposited on focused ion beam patterned substrates, well organized nanoparticles with adjustable magnetic anisotropy are obtained. Ferromagnetic resonance measurements performed on these samples reveal that the magnetic anisotropy originates mainly from the particle shape. 相似文献
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The eutectic mixture of octacosane (C28)–heptadecane (C17) as core material was successfully encapsulated with an acrylic-based polymer (polymethylmethacrylate; PMMA) as shell material through emulsion polymerization. The polymeric reaction occurred around the core material was characterized by FTIR spectroscopy analysis. The polarized optical microscopy, scanning electron microscopy and particle size distribution investigations showed that the most of the prepared capsules had almost spherical shape with non-unimodal size distribution in micro-nano range. The differential scanning calorimetry analysis results exhibited that the capsules including highest amount of the eutectic PCM had a melting temperature of about 21°C and a latent heat capacity of about 98 J/g. The high thermal durability of the prepared capsules was confirmed by thermogravimetric analysis. The thermal cycling test designated that the synthesized capsules had good long-term usage latent heat thermal energy storage (LHTES) performance and chemical stability. Furthermore; the fabricated capsules with (1: 2) shell/core ratio had a reasonable thermal conductivity. It can be drawn a conclusion from all results that the prepared capsules especially PMMA/(C28–C17) (1: 2) product is a hopeful PCM that can be evaluated for low-temperature LHTES applications. 相似文献