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761.
Posidonia oceanica (L.) Delile is an important endemic sea plant in the Mediterranean Sea. Its dead leaves are accumulated in the beaches and cause bad view and also odour in the touristical beaches. Therefore, these dead leaves accumulated on the beaches are collected and then burned in some beaches in Turkey. In the present study, the adsorption between dead leaves and uranium were studied in the aqueous solutions. The adsorption data obeyed the pseudo-second order kinetics. Among the studied isotherms, the data were well in line with the Freundlich and Dubinin-Raduschkevich models and the maximum adsorption capacities obtained from these models were found as 5.67 and 9.81?mg?g?1, respectively. Negative values of Gibbs free energy showed that the adsorption was in spontaneous nature. In conclusion, the dead leaves of P. oceanica from touristic beaches might be collected and evaluated as a low-cost adsorbent for removal of uranium(VI) from aqueous solutions.  相似文献   
762.
Labeling of acetaminophen with I-131 and biodistribution in rats   总被引:1,自引:0,他引:1  
The aim of the present study was to label acetaminophen (APAP) with I-131 and to determine its radiopharmaceutical potential in rats. Acetaminophen was labeled with I-131 using the iodogen method. The radiochemical purity of (131)I-APAP was determined by RTLC and paper electrophoresis. The labeling yield was 94 +/- 4%. The biodistribution studies of the labeled compound (specific activity; 56.60 GBq/mmol) were performed in male Albino Wistar rats. The uptake of (131)I-APAP in some organs were determined at different time after injection to the rats. The radioactivity in each organ was counted and the percentage of injected activity per gram of tissue weight (%ID/g) for each organ and blood was calculated. (131)I-APAP uptake in the lung, liver, kidneys, pancreas, blood, stomach and some brain region, were observed. Thus, (131)I-APAP may be radiopharmaceutical for the imaging of the brain.  相似文献   
763.
In the present work, octachlorocyclotetraphosphazatetraene (1), N4P4Cl8, is reacted with aniline (2), 1-napthylamine (4) and 2-aminoanthracene (6) to give octakis(arylamino)cyclotetraphosphazenes (3, 5 and 7). These cyclotetraphosphazene compounds (3, 5 and 7) have been fully characterized by elemental analysis, mass (MS), FT-IR, 1H and 31P NMR spectroscopies. The molecular and crystal structures of 5 have been characterized by X-ray crystallography. The structure of 5 is monoclinic with the space group P21/c. The octakis(1-napthylamino)-(5) and octakis(2-aminoanthracene)-(7) cyclotetraphosphazene compounds have been synthesised for the first time in this study. The fluorescence properties of 3, 5 and 7 have been investigated in tetrahydrofuran (THF) and have been shown to have highly fluorescence behavior. This work also presents the quenching of arylamino substituted cyclotetraphosphazene derivatives (3, 5 and 7) by p-benzoquinone (BQ) or hydroquinone (HQ).  相似文献   
764.
Synthesis of four different types of ligands Ar[COC(NOH)R] n (Ar = biphenyl, n = 1, HL1; Ar = biphenyl, n = 2, H2L2; Ar = diphenylmethane, n = 1, HL3; Ar = diphenylmethane, n = 2, H2L4; R = furfurylamine in all ligands) and their dinuclear Co2+, Ni2+, Cu2+, and Zn2+ complexes is reported herein. These compounds were characterized by elemental analysis, ICP-OES, FT-IR spectra, and magnetic susceptibility measurements. The ligands were further characterized by 1H NMR. The results suggest that dinuclear complexes of HL1 and HL3 have a metal to ligand mole ratio of 2: 2 and dinuclear complexes H2L2 and H2L4 have a metal to ligand mole ratio of 2: 1. Square pyramidal or octahedral structures are proposed for complexes of oxime ligands. Furthermore, extraction abilities of the four ligands were also evaluated in chloroform using selected transition metal picrates such as Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Hg2+, Pb2+. The ligands show strong binding ability towards Hg2+ and Cu2+ ions.  相似文献   
765.
5,6-Dihydrobenzo[h]quinoline derivatives 4af and 5ac were prepared via condensation of the corresponding arylidenes 2, with 1-tetralone in the presence of ammonium acetate and sodium methoxide, respectively, following thermal, microwave and ultrasound methodologies. The yields of 4af were moderate when the latter two methodologies used, but the products were pure. Ultrasound and microwave irradiation methods were also used in the synthesis of 4-aryl-3-cyano-1,2,5,6-tetrahydro-benzo[h]quinoline-2-ones (6ae) and its analogues 7a,b. The majority of compounds 47 were synthesized via one-pot multicomponent reactions of aldehydes, active cyanomethylene compounds, 1-tetralone and ammonium acetate. Attempts to cyclocondensation of the aminocyano derivative 4a,d with acetic anhydride in presence of conc. H2SO4 failed; instead the acetylamino derivative 8 was isolated. On the other hand, refluxing of 4d with formamide in DMF led to the formation of dihydrobenzo-pyrimidoquinoline 9 giving good yield. All prepared condensates were structurally elucidated by various spectroscopic methods. Screening of the potential cytotoxicity for compounds 4af on five cell lines, namely: colorectal carcinoma (HCT-116), Hepatocellular carcinoma (HEPG2), Human breast adenocarcinoma (MCF7), Cervix adenocarcinoma (HELA) and Glioblastoma (U251), did not show any cytotoxic activity.  相似文献   
766.
Selecting the most suitable registry alternative for shipping fleets has become a highly complex strategic activity for ship owners in the maritime transportation industry, and necessitates consideration of both internal and external environmental factors, which can be both qualitative and quantitative. The aim of this paper is to propose an originally structured multi-methodological approach based on the systematic application of the SWOT analysis, the AHP and the TOPSIS methods to support the critical decision process on shipping registry selection under multiple criteria. In the proposed approach, the SWOT analysis is utilized to determine the key assessment factors on the shipping registry decision and to structure the decision hierarchy. While the AHP is used to measure the relative importance of evaluation criteria in this decision hierarchy, the TOPSIS is applied to rank the shipping registry alternatives. As a case study, major open registries are analyzed to select the most suitable of them for the fleet that is operated by a worldwide ship owner. The results show that the proposed multi-methodological approach takes the advantages of the SWOT analysis, the AHP and the TOPSIS to select the most suitable shipping registry. The proposed approach also provides a relatively simple and very well suited decision-making tool for this type of strategic decision making problem.  相似文献   
767.
Size matters: Nanometer‐sized gaps in aggregates of silver nanoparticles are generated by covering the nanoparticle surface with a bilayer of cetyltrimethylammonium bromide. The nanometer‐ to micrometer‐sized wells are lithographically generated on polydimethylsiloxane surfaces. The wells filled with the modified nanoparticles (see picture) and the effect of the aggregate size on SERS enhancement are investigated.

  相似文献   

768.
This paper is concerned with the broad class of Liner Thermoelastic (LTE) models for Shape Memory Polymers (SMPs) which unifies numerous constitutive theories proposed in the literature for this kind of smart material. It is shown that the response functions for the general model of this class may be determined directly from experimental data measured in standard thermomechanical cyclic tests. (© 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
769.
A simple and sensitive spectrofluorimetric method was developed for the determination of ezetimibe in its pharmaceutical formulations. The proposed method is based on investigation of the fluorescence spectral behavior of ezetimibe in sodium dodecyl sulfate (SDS) micellar system. In aqueous solution of acetate buffer pH 5.0, the fluorescence intensity of ezetimibe was greatly enhanced, 200% enhancement, in the presence of SDS. The fluorescence intensity of ezetimibe was measured at 380 nm after excitation at 268 nm. The fluorescence-concentration plot was rectilinear over the range of 0.03–3.0 μg/mL with lower detection limit of 3.08 × 10−3 μg/mL. The method was successfully applied to the analysis of ezetimibe in its commercial tablets; the results were in good agreement with those obtained with the reported method. The application of the proposed method was extended to the stability studies of ezetimibe after exposure to different forced degradation conditions, such as acidic, alkaline, photo and oxidative conditions, according to ICH guidelines.  相似文献   
770.
Leaves and aerial parts of Malva neglecta Wallr. have been traditionally used in Anatolia for the treatment of pain, inflammation, hemorrhoids, renal stones, constipation, and infertility. This study investigated the effects of M. neglecta leaves in a rat endometriosis model. The dried plant material was extracted with n-hexane, ethyl acetate, and methanol, successively. Experimental endometriosis was surgically induced in six-week-old female, non-pregnant, Wistar albino rats by autotransplant of endometrial tissue to the abdominal wall. After twenty-eight days, rats were evaluated for a second laparotomy. Endometrial foci areas were assessed, and intraabdominal adhesions were scored. Rats were divided into five groups as control, n-hexane, ethyl acetate, methanol, and aqueous extracts, as well as reference. At the end of the treatment, all rats were sacrificed and endometriotic foci areas and intraabdominal adhesions were re-evaluated and compared with the previous findings. Moreover, peritoneal fluid was collected to detect tumor necrosis factor- α (TNF-α), vascular endothelial growth factor (VEGF), and interleukin-6 (IL-6) levels, and cDNA synthesis, and a quantitative real-time polymerase chain reaction (PCR) test was done. The phytochemical content of the most active extract was determined using High-Performance Liquid Chromatography (HPLC). Both endometrial volume and adhesion score decreased significantly in the group treated with methanol extract. In addition, significant decreases were observed in TNF-α, VEGF, and IL-6 levels in animals administered methanol extract. HPLC results showed that the activity caused by the methanol extract of M. neglecta was due to the polyphenols. Taken together, these novel findings indicate that M. neglecta may be a promising alternative for the treatment of endometriosis.  相似文献   
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