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排序方式: 共有302条查询结果,搜索用时 15 毫秒
221.
222.
E.I. Shabana M.I. El-Dessouky M.M. Abed El-Aziz 《Journal of Radioanalytical and Nuclear Chemistry》2001,250(3):531-536
Empirical formulae, based upon thermo-analytical investigations, have been assigned for different cerium(IV) antimonate samples prepared under varying conditions of precipitation. Equilibria and apparent Na+-capacity measurements at different pH values were carried out to throw more light on their sorption behavior. From the general curve shape analysis of the capacity-pH curves, the possible ion exchange site acidity and site group concentration were characterized. The samples showed almost bifunctional cation exchange behavior. The results obtained are discussed in detail referring to some conclusions. 相似文献
223.
Communicated by N.R. Reilly 相似文献
224.
Aromatic nitrations by tetranitromethane are shown to be photo-chemically initiated and are believed to proceed via trinitromethyl nitrite. 相似文献
225.
Faheem A. Rizvi Tanveer H. Bokhari S. Roohi A. Mushtaq 《Journal of Radioanalytical and Nuclear Chemistry》2012,293(1):303-307
Doxorubicin (DOX) is an anthracycline antineoplastic and one of the most potent and widely used drugs in clinical oncology. It is used in the treatment of a wide variety of cancers. The aim of this study was the direct labeling of DOX with 99mTc; its optimization, characterization and quality control of the radiolabeled DOX. Labeling efficiency was determined by paper chromatography. More than 92% labeling was obtained at pH 6?C7, 10?C12???g stannous chloride and 200???g of DOX. The stability of 99mTc?CDOX was studied up to 5?h. All the experiments were performed at room temperature (25±?2?°C). The characterization of the labeling compound was performed by HPLC and electrophoresis. Electrophoresis indicates that labeled DOX has no charge and HPLC shows single specie of labeled compound. 相似文献
226.
In?vitro antifungal activity and phytochemical constituents of essential oil, aqueous, methanol and chloroform extract of Eucalyptus citriodora Hook leaves were investigated. A qualitative phytochemical analysis was performed for the detection of alkaloids, cardiac glycosides, flavonoids, saponins, sterols, tannins and phenols. Methanolic extract holds all identified biochemical constituents except for the tannin. While these biochemical constituents were found to be absent in essential oil, aqueous and chloroform extracts with the exception of sterols, cardiac glycosides and phenols in essential oil and sterols and phenols in aqueous and chloroform extracts. Antimycotic activity of four fractions of E. citriodora was investigated through agar-well diffusion method against four post-harvest fungi, namely, Aspergillus flavus Link ex Gray, Aspergillus fumigatus Fres., Aspergillus nidulans Eidam ex Win and Aspergillus terreus Thom. The results revealed maximum fungal growth inhibition by methanolic extract (14.5%) followed by essential oil (12.9%), chloroform extract (10.15%) and aqueous extract (10%). 相似文献
227.
228.
ABSTRACTProfessor Graham Higman has defined coset diagrams for the action of PGL(2,?) on the projective line over a finite field Fq, denoted by PL(Fq), where q is a prime power. These diagrams are composed of circuits. In this paper, we answer the question, for a fixed number of triangles T, how many distinct circuits of length 4, are evolved? 相似文献
229.
A new formulation of a freeze-dried kit for the labeling of tetrofosmin with technetium-99m has been developed. The kit contains
lyophilized mixture of 0.320 mg tetrofosmin [6,9-bis(2-ethoxyethyl)-3,12-dioxa-6,9-diphosphatetradecane], 0.025 mg stannous
chloride dihydrate, 5 mg sodium tartrate and 5 mg sodium hydrogen carbonate. The product contains no antimicrobial preservative.
When 99mTc pertechnetate up to 6 mL saline containing 200 mCi is added to lyophilized mixture, a lipophilic, cationic 99mTc complex is formed, 99mTc-tetrofosmin. The performance of newly developed kit is compared with commercially available MYOVIEW kit for heart imaging.
The patient studies show that the images of heart obtained by 99mTc-tetrofosmin prepared by new formulation are equally good to MYOVIEW. 相似文献
230.
Hassen Bel Abed Nils Weißing Jens Schoene Jannik Paulus Norbert Sewald Marc Nazaré 《Tetrahedron letters》2018,59(19):1813-1815
A simple and novel methodology for the synthesis of 3-perfluoroalkylated-2H-indazole derivatives has been elaborated. The perfluoroalkylation of readily available 2-nitrobenzaldimines bearing electron donating groups was performed using the Ruppert-Prakash reagent and its analogues to afford α-difluoromethylated, α-trifluoromethylated and α-pentafluoroethylated benzylamines. A final reductive cyclization mediated by SnCl2·2H2O led to 2H-indazoles containing perfluoroalkyl groups via the generation of a new NN bond in moderate to good yields. 相似文献