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排序方式: 共有396条查询结果,搜索用时 15 毫秒
91.
Sheldon PD Trilling GH Petersen A Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Ross MC Rowson PC Schaad T Schellman H Schmidke WB de la Vaissiere C Wood DR Yelton JM Zaiser aC 《Physical review letters》1986,57(12):1398-1401
92.
The application of the CoMSA method to analyze 3D QSAR of 50 steroid aromatase inhibitors is described. The 3D QSAR model obtained, reaching a value of cross-validated q(2) = 0.96 (s = 0.31), significantly outperforms those reported in the literature for the CoMFA or CoSA (CoSASA). It is shown that the Uniformative Variable Elimination UVE-PLS or modified iterative UVE procedure (IVE-PLS) can be used for indicating the regions contributing to the binding activity. Thus, after separating the series into two groups of the training and test molecules quite correct external predictions result from the processing of the training set. We proved that the procedure of the data elimination provides stable results, if tested in 50 random runs of the IVE-PLS-CoMSA with different training/test sets. Depending upon the procedure used the quality of the predictions for 25 test molecules is given by SDEP = sum(y(pred)-y(obs))(2)/n)(1/2) = 0.321 - 0.782. 相似文献
93.
Jacek Goworek Mieczysław Jaroniec Jarosław Ościk Ryszard Kusak 《Monatshefte für Chemie / Chemical Monthly》1986,117(5):579-588
The excess adsorption isotherms ofn-pentanol, pentan-2-ol and 2-methylbutan-2-ol from binary and ternary solutions in benzene andn-heptane were measured. Experimental adsorption data are discussed in terms of a multilayer model of the surface phase. The main assumption of this model is that the surface layers being near the solid surface contain the molecules of the preferentially adsorbed component only. The phase-exchange reaction of molecules between bulk phase and last surface layer has been taken into account.On the basis of this theory it has been established for the investigated systems that the surface phase contains three molecular layers. Simultaneously appropriate surface phase capacities were determined.
Eine einfache Untersuchungsmethode für Mehrschicht-Effekte bei der Adsorption von Alkoholen an Kieselgel
Zusammenfassung Die Adsorptionsisothermen binärer und ternärer flüssiger Mischungen vonn-Pentanol, 2-Pentanol oder 2-Methyl-2-butanol in Benzol und/odern-Heptan wurden bezüglich Kieselgel gemessen. Die experimentellen Daten der Adsorption wurden mittels des Mehrschichts-Modells der Oberflächenphase diskutiert. Die Hauptvoraussetzung dieses Modells ist die Annahme, daß die Oberflächenschichten, die sich in der Nähe des Kieselgels befinden, nur Moleküle der bevorzugt adsorbierten Komponente enthalten. Es wurde auch die Phasen-Austauschreaktion von Molekülen zwischen Phaseninnerem und der letzten Oberflächenschicht in Betracht gezogen.Auf der Basis dieser Theorie wurde für die untersuchten Systeme festgestellt, daß die Oberflächenphase aus drei Molekülschichten besteht. Außerdem wurden die ermittelten Volumina der Oberflächenphase berechnet.相似文献
94.
Gidal G Boyer J Butler F Cords D Abrams GS Amidei D Baden AR Barklow T Boyarski AM Burchat P Burke DL Dorfan JM Feldman GJ Gladney L Gold MS Goldhaber G Golding LJ Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissière C Wood DR Yelton JM Zaiser C 《Physical review letters》1987,59(18):2012-2015
95.
Wendt C Abrams G Amidei D Baden AR Barklow T Boyarski AM Boyer J Burchat PR Burke DL Butler F Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding L Haggerty J Hanson G Hayes K Herrup D Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Karlen D Klein SR Lankford AJ Larsen RR LeClaire BW Levi M Lockyer NS Lüth V Matteuzzi C Nelson ME Ong RA Perl ML Richter B Riles K Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH de la Vaissiere C Wood DR Yelton JM 《Physical review letters》1987,58(18):1810-1813
96.
A series of 16- and 18-membered azo- and azoxythiacrown ethers have been synthesized by reductive macrocyclization of the respective bis(nitrophenoxy)oxaalkanes. The aromatic residues located in the polyether region of the molecule were introduced to macrocyclic skeletons and their affinities toward different groups of metal cations in ion-selective electrodes were described. X-ray structures for one dinitropodand and one azoxybenzothiacrown exhibiting strong π–π and π–H interactions have been found. 相似文献
97.
98.
Rafał Głaszczka Jarosław Jaźwiński Bohdan Kamieński Monika Kamińska 《Tetrahedron: Asymmetry》2010,21(19):2346-2355
Complexation of rhodium(II) dimeric tetraacylates: tetraacetate Rh2AcO4, tetratrifluoroacetate Rh2TFA4 , and (S)-Mosher’s acid salt Rh2MTPA4 with both enantiomerically pure and racemic methionine and its derivatives: hydrochloric salt of methionine, hydrochloric salt of methionine methyl ester, N-formyl methionine, N-phthaloyl methionine, N-phthaloyl methyl ester of methionine, and methyl ester of N,N-dimethylmethionine has been investigated by means of 1H and 13C nuclear magnetic resonance (1H and 13C NMR) and absorption electronic spectroscopy in the visible range. Complexation processes were investigated in D2O or CDCl3 solutions, depending on the ligands’ and rhodium salts’ solubilities. Some supporting measurements were performed in the solid phase, using 13C and 15N CPMAS NMR techniques.All ligands investigated form 1:1 and 1:2 adducts in the solution, depending on the rhodium salt to ligand molar ratios. The complexation site in the ligands (S atom) was deduced on the basis of the NMR parameter adduct formation shift (Δδ = δadduct ? δligand) and calculated chemical shifts (DFT, NMR GIAO). In the cases of the Rh2TFA4 and Rh2MTPA4 adducts, decreasing the temperature within the range 220–254 K slowed down the ligand exchange and allowed us to observe the signals of all diastereoisomers in the 1H and 13C NMR spectra. 相似文献
99.
Walczak Rafał Gawęda Weronika Dudek Jakub Choiński Jarosław Bilewicz Aleksander 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):249-254
Journal of Radioanalytical and Nuclear Chemistry - The aim of the study was to evaluate the labeling yield of 44Sc-DOTATATE radiobioconjugate when the labeling is performed in the presence of... 相似文献
100.
Jarosław Błasczyk Michał W. Wieczorek Danuta Krajewska Andrzej Okruszek Wojciech J. Stec 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1)
Abstract The title compound 1 [31P NMR (CD3CN): σ=36.7ppm] has been identified among the products of controlled hydrolysis of 2-dimethoxyphosphory1-1,3,2-dithiaphospholane (2) [1]. 相似文献