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21.
The aim of this study was to label ascorbic acid with (99m)Tc and to investigate its radiopharmaceutical potential in rats. Ascorbic acid was labeled with (99m)Tc using the stannous chloride method. The radiochemical purity of [(99m)Tc]ascorbic acid ((99m)Tc-AA) was determined by RTLC, paper electrophoresis, and RHPLC methods. The labeling yield was found to be 93+/-5.0%. The maximum labeling yield of (99m)Tc-AA was determined at pH 5 and 25 degrees C. The biodistribution studies related to (99m)Tc-AA were done in male albino Wistar rats. (99m)Tc-AA, which has a specific activity of 13.02 GBq/mmol, was administered into the tail vein of the rats. The rats were sacrificed at 15, 30, 60, and 120 min after the injection by heart puncture under ether anaesthesia. The organs were weighed after removal. Their activities were counted using a Cd(Te) detector equipped with a RAD 501 count system. The %ID/g (% of injected dose per gram of tissue weight) in each organ and in blood was calculated. Maximum uptake of (99m)Tc-AA was observed in prostate and kidneys at the 60th min. (99m)Tc-AA may be a promising radiopharmaceutical for the imaging of prostate and kidneys.  相似文献   
22.
As the service industries grow, tasks are not directly assigned to the skills but the knowledge of the worker which is to be valued more in finding the best match. The problem becomes difficult mainly because the match has to be seen with the objectives of both sides. Assignment methods fail to respond to a multi-objective, multi-constraint problem with complicated match; whereas, metaheuristics is preferable based on computational simplicity. A conditional genetic algorithm is developed in this study to propose both global and composite match using different fitness functions. This algorithm kills the infeasibilities to achieve the maximum number of matches. The proposed algorithm is applied on an academic problem of multi-alternative candidates and multi-alternative tasks (m × n problem) in two stages. In the first stage, four different fitness functions are evaluated and in the second stage using one of the fitness functions global and composite matching have been compared. The achievements will contribute both to the academic and business world.  相似文献   
23.
We demonstrate a proof-of-concept optical spectroscopic system for bioaerosol-particle fluorescence detection, in which a pulsed high-power laser is replaced by a highly compact linear array of sequentially fired light from blue light-emitting diodes. The results suggest that low-cost, compact optical aerosol detection may be feasible with the contemporary emergence of efficient UV light-emitting diodes.  相似文献   
24.
As a result of major developments in communication technology, the electromagnetic spectrum is now a ‘significant’ but ‘scarce’ resource. The broadcasting frequencies/channels/ bands must be assigned to applicants in an optimal manner so that larger numbers of applicants can be accommodated. This problem is constructed as a 0–1 programming problem. Numerical examples are also presented.  相似文献   
25.
Hydrogen evolution at polarized liquid–liquid interfaces [water/1,2‐dichloroethane (DCE)] by the electron donor decamethylferrocene (DMFc) is catalyzed efficiently by the fabricated cobalt sulfide (CoS) nanoparticles and nanocomposites of CoS nanoparticles formed on multi‐walled carbon nanotubes (CoS/CNT). The suspended CoS/CNT nanocomposite catalysts at the interface show a higher catalytic activity for the hydrogen evolution reaction (HER) than the CoS nanoparticles due to the high dispersity and conductivity of the CNT materials, which can serve as the main charge transport pathways for the injection of electrons to attain the catalytic sites of the nanoparticles. The reaction rate increased more than 1000‐fold and 300‐fold by using CoS/CNT and CoS catalysts, respectively, when compared to a non‐catalyzed reaction.  相似文献   
26.
18FDG conjugated magnetic iron oxide nanoparticles (MNPs) were synthesized as PET-MR hybrid imaging agent. Synthesized and characterized NPs were then applied to MCF-7 human breast cancer cells. 18FDG conjugated MNPs exhibited the cell incorporation ratio up to 30 %. As well as the characterization studies, apoptotic effects were observed depending on the cellular incorporations by the time. In conclusion, synthesized structures could have a potential as hybrid imaging agent in PET-MR imaging systems besides apoptotic effect on cancer cells.  相似文献   
27.
The thermal and magnetothermal properties of La0.5Pr0.5Mn2Si2 and isostructural LaFe2Si2 intermetallic compounds in the temperature range 4.5-303 K are reported with and without applied magnetic field. The electronic, lattice, and magnetic contributions to the heat capacity of La0.5Pr0.5Mn2Si2 are determined and analyzed. We have determined and from heat capacity experiments; the values are in line with those from the magnetization measurements. We conclude that in order to observe the anomaly in the heat capacity data around in the system, the transition around should occur in a narrow temperature interval.  相似文献   
28.
Polyhedral Oligomeric Silsesquioxanes (POSS) are cage‐structured inorganic–organic hybrid materials which can be used in various industrial applications. It is recently discovered that POSS structures with certain functional groups can be solubilized in supercritical CO2 allowing their applications in environmentally benign supercritical processing of materials. In this theoretical study, nature and energetics of the interactions of octatrifluoropropyl POSS, octatrifluoromethyl POSS, and octamethyl POSS with CO2 are investigated according to the principles of density functional theory (DFT) by use of Gaussian 09 software. Simulations show that CO2‐octamethyl POSS pair has hydrogen bonding between the O atom of CO2 and the H atom of the methyl group, and CO2‐octatrifluoromethyl POSS pair has interactions between the C atom of CO2 and the F atom of the trifluoromethyl group. CO2‐octatrifluoropropyl POSS pair is found to have both interaction types. The octamethyl, the octatrifluoromethyl and the octatrifluoropropyl POSS structures have interaction energies of ?2.18 kcal/mol, ?3.10 kcal/mol, and ?3.77 kcal/mol, respectively. This shows that the presence of Lewis acid–Lewis base interaction between C and F instead of hydrogen bonding between O and H atoms enhances the interaction of the molecule with CO2, while the presence of both interactions between the octatrifluoropropyl POSS‐CO2 pair makes the intermolecular interaction even stronger.  相似文献   
29.
Aqueous colloidal suspension of iron oxide nanoparticles has been synthesized. Z-potential of iron oxide nanoparticles stabilized by citric acid was −35±3 mV. Iron oxide nanoparticles have been characterized by the light scattering method and transmission electron microscopy. The polyelectrolyte/iron oxide nanoparticle thin films with different numbers of iron oxide nanoparticle layers have been prepared on the surface of silicon substrates via the layer-by-layer assembly technique. The physical properties and chemical composition of nanocomposite thin films have been studied by atomic force microscopy, magnetic force microscopy, magnetization measurements, Raman spectroscopy. Using the analysis of experimental data it was established, that the magnetic properties of nanocomposite films depended on the number of iron oxide nanoparticle layers, the size of iron oxide nanoparticle aggregates, the distance between aggregates, and the chemical composition of iron oxide nanoparticles embedded into the nanocomposite films. The magnetic permeability of nanocomposite coatings has been calculated. The magnetic permeability values depend on the number of iron oxide nanoparticle layers in nanocomposite film.  相似文献   
30.
In this small note, we will characterize the boundedness, compactness and closedness of the range of the multiplication operators on Lorentz-Karamata-Bochner spaces L p,q;b (Ω,X) for p, q ∈ (0,∞].  相似文献   
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