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排序方式: 共有124条查询结果,搜索用时 31 毫秒
31.
Gorkem Yildiz Ayfer Yurt Kilcar E. Ilker Medine Volkan Tekin Ozge Kozgus Guldu F. Zumrut Biber Muftuler 《Journal of Radioanalytical and Nuclear Chemistry》2017,311(2):1043-1052
Encapsulation with PLGA of I3C and radioiodination have been performed. Anticancerogenic effects of I3C and I3C-PLGA have been investigated utilizing in vitro methods on breast adenocarcinoma epithelial (MCF7), colon adenocarcinoma epithelial (Caco2), prostate carcinoma epithelial (PC3) cells. Characterization of I3C-PLGA have been performed with DLS method and SEM analysis. I3C and I3C-PLGA compounds have been radiolabeled in high yields with 131I which is widely used for diagnosis and treatment in Nuclear Medicine. All experimental results demonstrated that radioiodinated compounds are promising in order to be used in Nuclear Medicine as well as present study contributed previously reported studies. 相似文献
32.
Bilsen Tural ?. Betül Sopac? Ayhan S. Demir Mürvet Volkan 《Journal of Physics and Chemistry of Solids》2011,72(8):968-973
γ-Fe2O3 (maghemite)-silica nanocomposite particles were synthesized using a sol-gel method. The condensation products of 3-glycidoxy propyltrimethoxy silane (GPTMS) and nitrilotriacetic acid (NTA) were introduced onto the surfaces of the γ-Fe2O3-silica nanocomposite particles and subsequently, these modified surfaces were complexed with cobalt (Co+2) metal ions. A possibility of using these surface modified γ-Fe2O3-silica particles for the purification of 6×histidine tagged recombinant benzaldehyde lyase (BAL, EC 4.1.2.38) based on magnetic separation was investigated. X-ray diffraction (XRD), thermal analysis, and vibrating sample magnetometry (VSM) methods were used to characterize the surface modified superparamagnetic γ-Fe2O3 (maghemite)-silica nanoparticles. XRD (Scherer's equation) results indicate that the primary particle size of maghemite was around 11 nm. Magnetic characterization results confirmed that the γ-Fe2O3 (maghemite)-silica nanoparticles were superparamagnetic. According to sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) results, these superparamagnetic nanoparticles specifically capture 6×His-tagged BAL from crude extract of Escherichia coli (E. coli) BL21(DE3)pLysS/BALHIS. This study shows that the surface modified γ-Fe2O3 (maghemite)-silica nanoparticles are eligible for immobilized metal-ion affinity adsorption for histidine tagged recombinant proteins with its high capacity (3.16±0.4 mg/g) and selectivity. 相似文献
33.
Adina Jung Volkan Filiz Sofia Rangou Kristian Buhr Petra Merten Janina Hahn Juliana Clodt Clarissa Abetz Volker Abetz 《Macromolecular rapid communications》2013,34(7):610-615
The formation of integral asymmetric membranes from ABC triblock terpolymers by non‐solvent‐induced phase separation is shown. They are compared with the AB diblock copolymer precursors. Triblock terpolymers of polystyrene‐block‐poly(2‐vinylpyridine)‐block‐poly(ethylene oxide) (PS‐b‐P2VP‐b‐PEO) with two compositions are investigated. The third block supports the formation of a membrane in a case, where the corresponding diblock copolymer does not form a good membrane. In addition, the hydrophilicity is increased by the third block and due to the hydroxyl group the possibility of post‐functionalization is given. The morphologies are imaged by scanning electron microscopy. The influence of the PEO on the membrane properties is analyzed by water flux, retention, and dynamic contact angle measurements.
34.
The investigation of K‐shell fluorescence parameters of Zn–Fe alloys with different grain size and microstrain values 下载免费PDF全文
N. Kup Aylikci J.M. Sampaio A. Kahoul V. Aylikci I.H. Karahan M. Guerra J.P. Santos J.P. Marques E. Tiraşoğlu 《X射线光谱测定》2017,46(4):242-251
It is known that zinc alloys with iron group metals have better corrosion resistance than pure zinc. Owing to the corrosion resistance of these alloys, Zn–Fe coatings are widely used in automotive industry and have excellent mechanical performance. In this work, we investigated the relationship between the changes in the measured X‐ray fluorescence parameters (Kβ/Kα, σKα and σKβ) and the changes in the structural parameters such as microstrain or grain size values for Zn–Fe alloys that were prepared with different pH values. To explain these changes, the Kα and KβX‐ray production cross sections, and the Kβ/KαX‐ray intensity ratio values were calculated by three different ways for the elemental forms of Zn and Fe. The structural parameters, such as microstrain and grain size, were also calculated. We expect that the outer shell electronic distribution affects the structural parameters of the produced Zn–Fe alloys, changing the measured Kα and KβX‐ray production cross sections, and the Kβ/KαX‐ray intensity ratio values. We also show that Zn–Fe alloy mi nimum microstrain value corresponds to the maximum changes in KβX‐ray production cross‐section values of Fe and Zn. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
35.
Quantum Fisher Information of Decohered W and GHZ Superposition States with Arbitrary Relative Phase
Volkan Erol 《International Journal of Theoretical Physics》2017,56(10):3202-3208
Quantum Fisher Information (QFI) is a very useful concept for analyzing situations that require phase sensitivity. It become a popular topic especially in Quantum Metrology domain. In this work, we study the changes in quantum Fisher information (QFI) values for one relative arbitrary phased quantum system consisting of a superposition of N Qubits W and GHZ states. In a recent work (Ozaydin et al. Int. J. Theor. Phys. 52, 2977, 2013), QFI values of this mentioned system for N qubits were studied. In this work, we extend this problem for the changes of QFI values in some noisy channels for the studied system. We show the changes in QFI depending on noise parameters. We report interesting results for different type of decoherence channels. We show the general case results for this problem. 相似文献
36.
37.
Zekeriyya Bahadır Volkan Numan Bulut Arif Mermer Neslihan Demirbaş Celal Duran Mustafa Soylak 《Journal of the Iranian Chemical Society》2018,15(6):1347-1354
A selective separation and preconcentration method for the determination of gold ions in water and ore samples has been developed using dispersive liquid–liquid microextraction, followed by flame atomic absorption spectrometry. 4-Ethyl-1(2-(4-(4-nitrophenyl)piperazin-1-yl)acetyl)thiosemicarbazide) (NPPTSC) has been used for the first time as new chelating reagent. A mixture of ethanol (dispersive solvent) and carbon tetrachloride (extraction solvent) was used. Some parameters affecting the extraction procedure including the type and volume of the extracting and dispersive solvents, HNO3 concentration, the chelating agent amount, volume of sample, and foreign ions have optimized. Also, the complex formation between gold ions and the ligand has been investigated in a methanol–water solution (1:1) using UV–visible spectrometry. The spectrophotometric titration data showed that of Au–NPPTSC complex composition was found to be 3:2. After optimizing the instrumental and experimental parameters, we achieved a detection limit of 1.5 µg L?1, a preconcentration factor of 50, and a linear dynamic range of 10.0–400.0 µg L?1. The relative standard deviation obtained 2.1% at 50 µg L?1 for gold ions (n = 10). The proposed method was successfully performed for the determination of gold in certified reference material, environmental water, and ore samples. 相似文献
38.
We report the development of 4D scanning transmission ultrafast electron microscopy (ST-UEM). The method was demonstrated in the imaging of silver nanowires and gold nanoparticles. For the wire, the mechanical motion and shape morphological dynamics were imaged, and from the images we obtained the resonance frequency and the dephasing time of the motion. Moreover, we demonstrate here the simultaneous acquisition of dark-field images and electron energy loss spectra from a single gold nanoparticle, which is not possible with conventional methods. The local probing capabilities of ST-UEM open new avenues for probing dynamic processes, from single isolated to embedded nanostructures, without being affected by the heterogeneous processes of ensemble-averaged dynamics. Such methodology promises to have wide-ranging applications in materials science and in single-particle biological imaging. 相似文献
39.
A new chloride generation system was designed for the direct, sensitive, rapid and accurate determination of the total germanium in complex matrices. It was aimed to improve the detection limit of chloride generation technique by increasing the vapor pressure of germanium tetrachloride (GeCl4). In order to do so, a novel joint vapor production and gas-liquid separation unit equipped with a home-made oven was incorporated to an ordinary nitrous oxide-acetylene flame atomic absorption spectrometer. Several variables such as reaction time, temperature and acid concentration have been investigated. The linear range for germanium determination was 0.1-10 ng mL−1 for 1 mL sampling volume with a detection limit (3 s) of 0.01 ng mL−1. The relative standard deviation (RSD) was 2.4% for nine replicates of a 1 ng mL−1 germanium solution. The method was validated by the analysis of one non-certified and two certified geochemical reference materials, respectively, CRM GSJ-JR-2 (Rhyolite), and GSJ-JR-1 (Rhyolite), and GBW 07107 (Chinese Rock). Selectivity of the method was investigated for Cd2+, Co2+, Cu2+, Fe3+, Ga3+, Hg2+, Ni2+, Pb2+, Sn2+, and Zn2+ ions and ionic species of As(III), Sb(III), Te(IV), and Se(IV). 相似文献
40.
Cloud-point extraction (CPE) using the non-ionic surfactant Triton X-100 was used successfully to remove a highly toxic dye, rhodamine 6G (R6G), from water and wastewater. The effects of different analytical parameters such as pH, concentration of Triton X-100 (TX-100) and salts, equilibrium temperature, and incubation time on the efficiency of the extraction of R6G were studied in detail, and optimum conditions for dye extraction were obtained. Thermodynamic parameters including changes in Gibbs free energy, enthalpy, and entropy were also calculated, and these parameters indicated that the CPE of R6G was feasible, spontaneous, and endothermic in the temperature range of 75-95 degrees C. The equilibrium solubilization capacity of TX-100 was found to be 1.10 mmol/mol by using Langmuir isotherm models. No significant interference effects were observed in the presence of phenol and its derivatives, some acidic and basic dyes and most of the anions and cations. It was concluded that the CPE process described in this paper can be an alternative technique for removal of dyes and other pollutants from waters and wastewaters. 相似文献