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排序方式: 共有162条查询结果,搜索用时 31 毫秒
41.
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
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43.
Celal Duran Mustafa Soylak Volkan Numan Bulut Ali Gundogdu Mehmet Tufekci Latif Elci Hasan Basri Senturk 《中国化学会会志》2007,54(3):625-634
A method for speciation of Cr(III) and Cr(VI) in real samples has been developed. Cr(VI) has been separated from Cr(III) and preconcentrated as its pyrrolidinedithiocarbamate (APDC) complex by using a column containing Amberlite XAD–2000 resin and determined by FAAS. Total chromium has also been determined by FAAS after conversion of Cr(III) to Cr(VI) by oxidation with KMnO4. Cr(III) has been calculated by subtracting Cr(VI) from the total. The effect of pH, flow‐rate, adsorption and batch capacity and effect of various metal cations and salt anions on the sorption onto the resin were investigated. The adsorption is quantitative in the pH range of 1.5–2.5, and Cr(VI) ion was desorbed by using H2SO4 in acetone. The recovery of Cr(VI) was 97 ± 4 at a 95% confidence level. The highest preconcentration factor was 80 for a 200 mL sample volume. The adsorption and batch capacity of sorbent were 7.4 and 8.0 mg g?1 Cr(VI), respectively, and loading half time was 5.0 min. The detection limit of Cr(VI) is 0.6 μg/L. The procedure has been applied to the determination and speciation of chromium in stream water, tap water, mineral spring water and spring water. Also, the proposed method was applied to total chromium preconcentration in microwave digested moss and rock samples with satisfactory results. The developed method was validated with CRM‐TMDW‐500 (Certified Reference Material Trace Metals in Drinking Water) and BCR‐CRM 144R s (Certified Reference Material Sewage Sludge, Domestic Origin) and the results obtained were in good agreement with the certified values. The relative standard deviations were below 6%. 相似文献
44.
A new sesquiterpene (1), and a halogenated C15 acetogenin (2), a stereoisomer of neoisoprelaurefucin were isolated from Laurencia obtusa. Four known compounds laurencienyne (3), rogiolenyne B (4), obtusenol (5), and (3E)-dactomelyne (6) were also isolated from this alga. Rogiolenyne B (4) and (3E)-dactomelyne (6) were found for the first from this species. The structures of these compounds were elucidated by spectroscopic methods. The unambiguous assignments of the 1H and 13C NMR spectral data of (5) and 13C NMR data of (6) were also reported for the first time. 相似文献
45.
A library of 1,3-disubstituted indoles has been prepared via an iterative Mannich reaction sequence. The first Mannich reaction with secondary amines and formaldehyde preferentially yields 3-aminomethyl indoles, while the second Mannich reaction introduces an additional aminomethyl group at the N1-position of the indole ring. A library of 25 substituted indoles has thus been prepared in moderate to good yields with purity. 相似文献
46.
Investigation of equilibrium, kinetic, thermodynamic and mechanism of Basic Blue 16 adsorption by montmorillonitic clay 总被引:1,自引:0,他引:1
The adsorption of a cationic dye, Basic Blue 16 (BB16), by montmorillonitic clay was studied in detail. Changes in the molecular structure during adsorption were analyzed by FTIR spectroscopy. BB16 adsorption onto the clay mainly results from hydrogen bonding between OH and NH2 groups of dye molecules and OH groups of clay and electrostatic interaction between the negatively charged clay surface and cationic dye. The montmorillonitic clay dose had an inverse effect on the adsorption performance, while the highest dye removal was 305 mg/g at pH 3.6. An increase in temperature and dye concentration positively enhanced the adsorption capacity of the montmorillonitic clay. Temperature had no effect on the adsorption at a dye concentration less than 500 mg/L, while dye adsorption was positively enhanced at elevated dye concentrations. Three-parameter equations provided higher better fitting than two-parameter equations while the Freundlich model had the highest correlation coefficient and the lowest error values with experimental data. The BB16 adsorption was well followed by pseudo-second order model and the rate of adsorption process was controlled by surface and intraparticle diffusion. Thermodynamic evaluations revealed that the adsorption process was spontaneous and endothermic, while the randomness increased during adsorption. Experimental results indicate that montmorillonitic clay from Eskisehir is a promising adsorbent for the removal of cationic dye molecules from aqueous solutions. 相似文献
47.
In this paper, we have introduced elliptical harmonic motion in terms of elliptical numbers. In addition, we have found the relationships between the absolute, the relative and the sliding velocities and accelerations of the aforesaid motion. Furthermore, the canonical relative system of the motion has been defined. At last, we have obtained the Euler–Savary formula for the motion with the help of this relative system. 相似文献
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49.
In electrical machines, sheet-layered lamination stacks play an important role for the mechanical behavior of the system. Especially the interlayer between individual sheets and their interaction have a severe influence on the structure. In the context of performance and computational effort, it is desirable to avoid a full FE simulation of a lamination stack with every single sheet. Therefore, homogenization techniques are presented to identify a transversely isotropic surrogate material model, while Zero-Thickness elements are utilized during this process to cover the interplay of single sheets. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
50.
Volkan Eyupoglu Recep Ali Kumbasar Mustafa Isik 《Journal of Dispersion Science and Technology》2013,34(9):1309-1319
The study was conducted to investigate synergistic extraction of nickel from simulated spent Cr–Ni electroplating bath solutions by emulsion liquid membrane (ELM) process using 5,8-diethyl-7-hydroxydodecan-6-one oxime (LIX 63) and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A) as carriers. The importance of ELM composition and the properties of simulated spent electroplating bath solution have been optimized to synergistically extract nickel. The important parameters affecting the nickel extraction efficiency and ELM stability, such as acid concentration, stripping solution type and concentration, extractant concentration, surfactant concentration, and phase ratio, were experimentally studied. Along with obtained results, higher than 99% of nickel was selectively extracted within 30 minutes from simulated electroplating bath solutions that their metal concentrations was in the range of 100–500 mg/L. in the optimum conditions. The higher separation factor value of nickel over chromium (βNi/Cr) was obtained as 898. As a result, the nickel extraction kinetic was found to depend on PC88A, since extraction mechanism of PC88A is slower than that of LIX63. So, the combined use of LIX63 and PC88A improved the selective extraction of nickel in that process. 相似文献