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11.
We have presented a method for the fabrication of poly(3-thiophenyl acetic acid) (P3TAA)-BaFe12O19 nanocomposites by the in situ polymerization of P3TAA in the presence of synthesized BaFe12O19 nanoparticles. The nanoparticles and the nanocomposite were analyzed by XRD, FTIR, TGA, TEM, VSM and conductivity techniques for structural and physicochemical characteristics. Crystallographic analysis revealed the phase as hexaferrite and X-ray line profile fitting yielded a crystallite size of 32 nm. The particles, observed by TEM, exhibit irregular shapes and sizes between 100 and 500 nm, revealing polycrystalline character when compared with the crystallite size from XRD. FTIR and TGA analysis results show that P3TAA is conjugated to the particle surface via a carboxylate group and that the composite has a polymer content of ∼10%. Magnetic hysteresis curves do not saturate at high fields, which is a characteristic feature of fine particle systems with grain sizes smaller than 1 μm. Conductivity measurements showed a semiconductor character of the nanocomposite. 相似文献
12.
Semih Durmus 《Tetrahedron》2005,61(1):97-101
The synthesis and structural characterization of a dicationic imidazolium-linked cyclophane 7 is reported. In 7, two imidazolium units that have histamine dihydrochloride as a precursor are bridged by two 2,6-bis(bromomethyl)-pyridine. 相似文献
13.
Analytic solutions of the partial differential equations are needed to explain many phenomena seen in thermodynamics, aerodynamics, plasma physics, and other fields. In this paper, variational principle is analyzed of the integrable nonlinear Korteweg–de Vries (KdV) typed equation. In addition, exact solutions of this equation are obtained by using various methods such as direct integration, homogeneous balance method, Exp-function method, and Kudryashov method. 相似文献
14.
Analyses of temperature-dependent interface states,series resistances,and AC electrical conductivities of Al/p Si and Al/Bi_4Ti_3O_(12)/p Si structures by using the admittance spectroscopy method 下载免费PDF全文
In this study, Al/p-Si and Al/Bi4Ti3O12/p-Si structures are fabricated and their interface states (Nss), the values of series resistance (Rs), and AC electrical conductivity (σac) are obtained each as a function of temperature using admit- tance spectroscopy method which includes capacitance-voltage (C-V) and conductance-voltage (G-V) measurements. In addition, the effect of interfacial Bi4Ti3012 (BTO) layer on the performance of the structure is investigated. The voltage- dependent profiles of Nss and Rs are obtained from the high-low frequency capacitance method and the Nicollian method, respectively. Experimental results show that Nss and Rs, as strong functions of temperature and applied bias voltage, each exhibit a peak, whose position shifts towards the reverse bias region, in the depletion region. Such a peak behavior is attributed to the particular distribution of Nss and the reordering and restructuring of Nss under the effect of temperature. The values of activation energy (Ea), obtained from the slope of the Arrhenius plot, of both structures are obtained to be bias voltage-independent, and the Ea of the metal-ferroelectric-semiconductor (MFS) structure is found to be half that of the metal-semiconductor (MS) structure. Furthermore, other main electrical parameters, such as carrier concentration of acceptor atoms (NA), built-in potential (Vbi), Fermi energy (EF), image force barrier lowering (△φb), and barrier height (φb), are extracted using reverse bias C 2-V characteristics as a function of temperature. 相似文献
15.
Zehra Durmus Hüseyin Kavas Abdulhadi Baykal Muhammet S. Toprak 《Central European Journal of Chemistry》2009,7(3):555-559
A novel environmental friendly, room temperature route using an ionic liquid 1-n-butyl-3-methylimidazolium hydroxide ([BMIM]OH)
for the synthesis of Mn3O4 nanoparticles is presented. The product was characterized using Fourier transform infrared spectroscopy, X-ray powder diffraction,
and transmission electron microscopy. Phase purity was confirmed by XRD, and X-ray line profile fitting determined a crystallite
size of 42 ± 11 nm. TEM analysis revealed various morphologies. EPR measurements have indicated the existence of long-range
interactions, due to the wide range of particle sizes and morphologies observed.
相似文献
16.
Radiotherapy is one of the most common therapies for treating human cancers. Several studies have indicated that irradiation induces reactive oxygen species (ROS), which play an important role in radiation damage of the cell. It has been shown that Nigella sativa L. (NS) and reduced glutathione (GSH) have both an antiperoxidative effect on different tissues and a scavenger effect on ROS. The purpose of this study was to determine the antioxidant and radio-protective roles of NS and GSH against irradiation-induced oxidative injury in an experimental model. The NS group was administrated NS (1 mL/kg body weight), the GSH group was injected GSH (150 mg/kg body weight) and the control group was given physiologic saline solution (1 mL/kg body weight) for 30 consecutive days before exposure to a single dose of 6 Gy of radiation. Animals were sacrificed after irradiation. Malondialdehyde, nitrate, nitrite (oxidative stress markers) and ascorbic acid, retinol, beta-carotene, GSH and ceruloplasmin (nonenzymatic antioxidant markers) levels and peripheral blood lymphocytes were measured in all groups. There were statistically significant differences between the groups for all parameters (P < 0.05). Whole-body irradiation caused a significant increase in blood malondialdehyde, nitrate and nitrite levels. The blood oxidative stress marker levels in irradiated rats that were pretreated with NS and GSH were significantly decreased; however, non-enzymatic antioxidant levels were significantly increased. Also, our results suggest that NS and GSH administration prior to irradiation prevent the number of alpha-naphthyl acetate esterase peripheral blood T lymphocytes from declining. These results clearly show that NS and GSH treatment significantly antagonize the effects of radiation. Therefore, NS and GSH may be a beneficial agent in protection against ionizing radiation-related tissue injury. 相似文献
17.
Zehra Durmus Belma Zengin Kurt Işıl Gazioğlu Ece Sevgi Cagla Kizilarslan Hancer 《应用有机金属化学》2020,34(3):e5375
MIL53(Al)-SiO2@Fe3O4 composite was prepared by co-precipitation route with a typical Stöber synthetic process and ultrasonic-agitation, then subsequently utilized as a multi-component novel sorbent in solid-phase microextraction (SPME) of aflatoxin B1 in winter herbal teas. Microstructural properties of MIL53(Al)-SiO2@Fe3O4 composite was characterized by using Fourier transform infrared (FTIR) spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) methods, and Brunauer–Emmett–Teller (BET) surface area measurement. The MIL53(Al)-SiO2@Fe3O4 composite was found to be a very effective sorbent in spectrofluorimetric determination of aflatoxin B1 (AFB1) in winter herbal teas via magnetic solid-phase extraction (SPE) route. The proposed method showed a wide linear range from 0.5 to 150 ng/ml, low limit of detection (LOD = 0.5 ng/ml), and an acceptable recovery values (70.7–96.5%) in real samples analysis. This study shows that the suggested method possesses an important potential to use for detecting AFB1 in quality control laboratories. 相似文献
18.
Cansu Uzaras Uğur Avcıbaşı Hasan Demiroğlu Emin İlker Medine Ayfer Yurt Kılçar Fazilet Zümrüt Biber Müftüler Perihan Ünak 《Journal of Radioanalytical and Nuclear Chemistry》2016,307(1):131-140
The aim of this study is to determine the incorporations of PHT radiolabeled with 131I (131I-PHT) on U-87 MG, Daoy and A549 cancerous cell lines. For this, cold and radio-labeling studies were carried out. The radio-labeling yield of 131I-PHT was obtained about 95 %. Subsequently, cell culture studies were carried out and radio-labeling yields of 131I, 131I-PHT on U-87 MG, Daoy and A549 cancerous cells were investigated. Cell culture studies demonstrated that the incorporation values of 131I-PHT on the three cell lines decreased with increasing radioactivity. Consequently, 131I-PHT may be a good radiopharmaceutical for targeting radionuclide therapy of Central Nervous System Tumors. 相似文献
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20.
Perihan A. Khalaf-Alla 《应用有机金属化学》2020,34(5):e5628
New expected biologically active complexes for some of the first (Mn (II), Ni (II), Cu (II) and Zn (II)) and second (Rh (III) and Cd (II)) transitional metals rows with N-(2-Aminoethyl)-1,3-propanediamine as a ligand (AEPD)have been synthesized. All synthesized complexes were formed with 1:1 (metal: AEPD) stoichiometry except Ni (II) 1:2 (Ni: AEPD). The compounds were characterized by different analysis tools such as; elemental analysis, Fourier transform infrared (FTIR), 1H-NMR, mass spectra, thermal analysis, electronic spectra, magnetic measurement and molar conductance techniques. AEPD ligand interacted with all metal ions as tridentate ligand by using the nitrogen atoms. On the other hand, density functional theory (DFT) calculations have been performed to confirm the optimized geometrical structures for both AEPD and its complexes. Furthermore, coordination compounds were screened for their potential antibacterial activities against six pathogenic bacteria as well as one kind of fungi in comparison to standard antibiotics by agar well diffusion method. The results show that most of the complexes exhibit antibacterial and antifungal activities against these organisms. Rh (III)-AEPD complex exhibited the strongest antibacterial effect followed by the Cd (II) complex but as antifungal agents Cd (II) was the first and the second was Rh (III). Also, the anticancer activity was screened for these metal complexes against growth of human liver cancer HEPG2 tumor cell line and this inhibition activity of Cd (II) chelate was noticed to be more active with lowest IC50 than that of all other synthesized complexes. Unfortunately, Mn (II) and Rh (III) chelates lacked anticancer activity. The docking active sites interactions were evaluated using the selected protein for anticancer activity. Finally, antioxidant activity was studied. Mn (AEPD) showed maximum activity followed by complex of Rh (III). 相似文献