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121.
The synthesis of some benzo [b] thieno [2,3-f] - and [3,2-f] morphans by the Grewe method is described. Spectroscopic data of these compounds and of the intermediate isomeric tetrahydropyridines are included. A side-product isolated from the aluminum bromide cyclization of the 2-(2-benzothienylmethyl)tetrahydropyridine IVd is reported and a mechanism for its formation is proposed. 相似文献
122.
Ohne Zusammenfassung
Combined immunological and thin-layer chromatographic method of the determination of morphine相似文献
123.
Ibarra IA Lima E Loera S Bosch P Bulbulian S Lara V 《The journal of physical chemistry. B》2006,110(42):21086-21091
Cesium-exchanged A and X zeolites were loaded with cesium acetate species and thermally treated in order to inhibit the mobility of exchangeable cesium cations. The proposed procedure seems to block the cavities channels avoiding the releasing of cesium cations under the leaching conditions. The cesium impregnated species did not induce strong structural modifications if they are used in small amounts (0.2 meq/g zeolite), but they promote transformation toward cesium orthosilicate if they are loaded in amounts as high as 2 meq/g zeolite. This orthosilicate retains safely the cesium as it is a component of the lattice. 相似文献
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125.
Ivo Grabchev Evgenia Vasileva-Tonkova Desislava Staneva Paula Bosch Rositsa Kukeva Radostina Stoyanova 《International Journal of Polymer Analysis and Characterization》2018,23(1):45-57
A new polyamidoamine metallodendrimer modified with eight 1,8-naphthalimide units was synthesized. The Cu(II) complex has been investigated by EPR spectroscopy and it has shown that 17 copper ions have involved in the dendrimer complex. To confirm the presence of metallodendrimers on the cotton surface, scanning electron microscopy characterization has been used. In vitro antimicrobial activity of the metallodendrimer against different pathogens was investigated and compared to the dendrimer ligand free of copper ions. Both dendrimers were deposited on a cotton fabric and antibacterial activity of the treated cotton samples was investigated against model Gram-positive and Gram-negative bacteria. It has been shown that the studied dendrimers reduce bacterial growth and prevent the formation of biofilms. The metallodendrimer showed stronger antimicrobial and biofilm inhibiting abilities than those of the free of Cu(II) ions ligand. 相似文献
126.
Herrero-Martínez JM Izquierdo P Sales J Rosés M Bosch E 《Journal of separation science》2008,31(18):3170-3181
The retention behavior of a series of fat-soluble vitamins has been established on the basis of a polarity retention model: log k = (log k)(0) + p (P(m) (N) - P(s) (N)), with p being the polarity of the solute, P(m) (N) the mobile phase polarity, and (log k)(0) and P(m) (N) two parameters for the characterization of the stationary phase. To estimate the p-values of solutes, two approaches have been considered. The first one is based on the application of a QSPR model, derived from the molecular structure of solutes and their log P(o/w), while in the second one, the p-values are obtained from several experimental measurements. The quality of prediction of both approaches has also been evaluated, with the second one giving more accurate results for the most lipophilic vitamins. This model allows establishing the best conditions to separate and determine simultaneously some fat-soluble vitamins in dairy foods. 相似文献
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128.
The performance of the most common and also some other less common CE buffers has been tested for the pKa determination of several types of compounds (pyridine, amines, and phenols). The selected buffers cover a pH ranging from 3.7 to 11.8. Whereas some buffers, like acetic acid/acetate, BisTrisH+/BisTris, TrisH+/Tris, CHES/CHES-, and CAPS/CAPS- can be used with all type of analytes, others like ammonium/ammonia, butylammonium/butylammonia, ethylammonium/ethylammonia, diethylammonium/diethylammonia, and hydrogenphosphate/phosphate are not recommended because they interact with a wide range of compounds. The rest of the tested buffers (dihydrogenphosphate/hydrogenphosphate, MES/MES-, HEPES/HEPES-, and boric acid/borate) can show specific interactions depending on the nature of the analytes, and their use in some applications should be restricted. 相似文献
129.
A synthetic route to enantiopure cis-2,4-disubstituted and 2,4-bridged piperidines is reported, the key step being a stereoselective conjugate addition of an organocuprate to a phenylglycinol-derived unsaturated lactam bearing a substituent at the 8a-position. 相似文献
130.
SNPs are one of the main sources of DNA variation among humans. Their unique properties make them useful polymorphic markers for a wide range of fields, such as medicine, forensics, and population genetics. Although several high-throughput techniques have been (and are being) developed for the vast typing of SNPs in the medical context, population genetic studies involve the typing of few and select SNPs for targeted research. This results in SNPs having to be typed in multiple reactions, consuming large amounts of time and of DNA. In order to improve the current situation in the area of human Y-chromosome diversity studies, we decided to employ a system based on a multiplex oligo ligation assay/PCR (OLA/PCR) followed by CE to create a Y multiplex capable of distinguishing, in a single reaction, all the major haplogroups and as many subhaplogroups on the Y-chromosome phylogeny as possible. Our efforts resulted in the creation of a robust and accurate 35plex (35 SNPs in a single reaction) that when tested on 165 human DNA samples from different geographic areas, proved capable of assigning samples to their corresponding haplogroup. 相似文献