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41.
C. Acar S. Teksoz P. ünak F. Z. Biber Müftüler E. I. Medine 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(2):375-380
The aim of this study is to investigate stereoisomeric behavior of penicillamine and the effect of temperature on labeling.
In addition, it was explored how stereoisomerism affected biological behavior of them. In the present work, D- and L-enantiomers
of penicillamine(D-PA, L-PA) were labeled with 99mTc using SnCl2 as reducing agent and their radiopharmaceutical potentials were investigated. Quality control procedures were carried out
using thin layer radiochromatography (TLRC), electrophoresis and high performance liquid radiochromatography (HPLRC). HPRLC
chromatograms showed two peaks for 99mTc-D-PA, while a single peak was observed for 99mTc-L-PA at room temperature. However, the single peak was observed at 90 °C for both isomers. Labeling yields of each isomer
were found to be over 98%. Biological activity of these complexes was determined on male Albino Wistar rats by biodistribution
studies. While the biodistribution result of 99mTc-D-PA showed high uptake in the liver, maximum uptake of 99mTc-L-PA was observed in the kidneys. Both two complexes were cleared rapidly from the blood, mainly by the renal system. Since
the activity concentration of 99mTc-D-PA at the 30th minute in the kidneys and the liver reached a maximum value and at the 120th minute, it was removed by
renal and hepatobiliary excretion. As a result, it can be concluded that stereoisomerism affect not only the chemical behavior,
but also differs their biological behavior of these compounds. 相似文献
42.
Alper Tolga ?olak G?nül Pamuk Okan Zafer Ye?ilel Filiz Y?lmaz Orhan Büyükgüng?r 《Journal of chemical crystallography》2012,42(1):76-82
Abstract
The [Co(H2O)6][Co(pydc)2(en)]2·14H2O (1) compound (H2pydc = Pyridine-2,3-dicarboxylic acid and en = ethylenediamine) was synthesized and characterized by elemental analysis, magnetic and spectroscopic measurements (UV–Vis and IR spectra) and single crystal X-ray diffraction technique. There are two coordination spheres with different charges inside this aqueous compound of ionic character. The cationic part is composed of Co(II) encircled by six aqua ligand. Whereas the anionic part contains two anions complex unit each with −1 charge and have Co(III) ions in the centre. As a result different coordination spheres have cobalt ions with different states. The crystallographic analysis revealed that 1 consists of both discrete one-cationic and two-anionic entities, [Co(H2O)6]2+ and [Co(pydc)2(en)]2− and fourteen crystal water molecules. Two water molecules within the water cluster act as hydrogen-bonding acceptors, whereas one water molecule acts as a hydrogen-bonding donor to form a discrete water trimer. These water molecules have stabilized the crystal structure by strong hydrogen bonding interactions. 相似文献43.
The Pollution-Routing Problem (PRP) is a recently introduced extension of the classical Vehicle Routing Problem with Time Windows which consists of routing a number of vehicles to serve a set of customers, and determining their speed on each route segment so as to minimize a function comprising fuel, emission and driver costs. This paper presents an adaptive large neighborhood search for the PRP. Results of extensive computational experimentation confirm the efficiency of the algorithm. 相似文献
44.
Dr. Baran Sarac Dr. Yurii P. Ivanov Dr. Tolga Karazehir Dr. Barbara Putz Prof. A. Lindsay Greer Prof. A. Sezai Sarac Prof. Jürgen Eckert 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(37):8244-8253
Nanostructured metallic glass films (NMGF) can exhibit surface and intrinsic effects that give rise to unique physical and chemical properties. Here, a facile synthesis and electrochemical, structural, and morphologic characterization of Pd-Au-Si based MGs of approximately 50 nm thickness supported on Si/SiO2 is reported. Impressively, the maximum total hydrogen charge stored in the Pd-Au-Si nanofilm is equal to that in polycrystalline Pd films with 1 μm thickness in 0.1 m H2SO4 electrolyte. The same NMGF has a volumetric desorption charge that is more than eight times and 25 % higher than that of polycrystalline PdNF and Pd-Cu-Si NMGF with the same thickness supported on Si/SiO2, respectively. A significant number of nanovoids originating from PdHx crystals, and an increase in the average interatomic spacing is detected in Pd-Au-Si NMGF by high-resolution TEM. Such a high amount of hydrogen sorption is linked to the unique density fluctuations without any chemical segregation exclusively observed for this NMGF. 相似文献
45.
Journal of Thermal Analysis and Calorimetry - In this study, the geothermal energy powered Kalina cycle (GEP-KC) was optimized by using a multi-stage artificial neural network (ANN) analysis. The... 相似文献
46.
Elif Gungor Mustafa Burak Coban Hulya Kara Yasemin Acar 《Journal of Cluster Science》2018,29(3):533-540
A new open-cubane MnIII, [{(H2O)MnIIIL}{MnIIIL}]2·2(CH3OH).2(CH3CH2OH)·2Cl, 1 where H 2 L=[N-(2-hydroxyethyl)-3-methoxysalicylaldimine] has been synthesized and characterized by element analysis, FT-IR, solid UV–Vis spectroscopy and single crystal X-ray diffraction. The crystal structure determination shows an open-cubane tetranuclear complex. The Mn1 (Mn1i) ions is hexacoordinate by NO5 donor sets while the Mn2 (Mn2i) is pentacoordinate by NO4 donor sets. The solid state photoluminescence properties of complex 1 and its ligand H 2 L have been investigated under UV light at 349 nm in the visible region. H 2 L exhibits blue emission while complex 1 shows orange-red emission at room temperature. Variable-temperature magnetic susceptibility measurements on the complex 1 in the range 2–300 K indicate an antiferromagnetic interaction. 相似文献
47.
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
48.
Orhan Acar A. Rehber Türker Ziya Kl? 《Fresenius' Journal of Analytical Chemistry》1997,357(6):656-660
A comparative study on the efficiency of some tungsten containing chemical modifiers such as W, W+Pd, W+Rh, W+Pt and W+Ru
for thermal stabilization of Bi, In, Pb and Sb has been performed systematically by a Zeeman electrothermal atomization atomic
absorption spectrometer (ETAAS). The addition of tartaric acid (TA) as a reducing agent additionally to the mixed modifiers
was studied. A mixture of W+Pd+TA was found to be a powerful mixed modifier for the determination of Bi, In, Pb and Sb. Pretreatment
temperatures could be increased up to 1250–1500° C using this mixed modifier. The use of the mixed modifier results in an
enhanced accuracy and precision of the method and recovery rates above 97% for all samples. The W+Pd+TA mixed modifier was
applied to the determination of Bi and Pb in dissolved geological reference samples.
Received: 14 March 1996 / Revised: 3 June 1996 / Accepted: 30 June 1996 相似文献
49.
Pointwise convergence of q-Bernstein polynomials and their q-derivatives in the case of 0 < q < 1 is discussed. We study quantitative Voronovskaya type results for q-Bernstein polynomials and their q-derivatives. These theorems are given in terms of the modulus of continuity of q-derivative of f which is the main interest of this article. It is also shown that our results hold for continuous functions although those are given for two and three times continuously differentiable functions in classical case. 相似文献
50.