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111.
The transition current distribution for the low-lying 2+ state at 4.085 MeV in 208Pb obtained in a realistic cranked shell-model calculation is used to calculate the transverse PWBA form factor for inelastic electron scattering to this state. By keeping the same density but changing the velocity field to that of irrotational, incompressible flow the sensitivity of the form factor to the dynamics of nuclear vibrational motion is explored. It is found that the two flow patterns lead to significant, observable differences in the form factors. 相似文献
112.
C. Năstăsescu B. Torrecillas F. Van Oystaeyen 《Algebras and Representation Theory》2008,11(2):179-190
Let C be a coalgebra over a field k. The aim of this paper is to study the following problem : (P) If C is a k-coalgebra such that C is a generator for the category of left comodules, is C a left quasi-co-Frobenius coalgebra ? The converse always holds. We show that if C has a finite coradical series, the answer is positive. 相似文献
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Raoul R. Nigmatulin Alexander P. Alekhin Dumitru Baleanu Erdal Dinç Zafer Üstündağ Haslet Ekşi Ali Osman Solak 《Electroanalysis》2010,22(4):419-426
The effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms was studied for the statistical characterization of nitrobenzene (NB) and nitroazobenzene (NAB)‐modified glassy carbon (GC) surfaces. Both NB and NAB nanofilms were obtained by the electrochemical reduction of the diazonium tetrafluoroborate salts in acetonitrile using cyclic voltammetry (CV). The modified surfaces were denoted as GC‐(NB)n and GC‐(NAB)n, respectively, where n indicates the number of CV cycles performed during modification. Reflective IR signals of the normalized NB and NAB nanofilms and GC were used for the quantitative evaluation of the effect of the potential cycles on the reflective IR signals of nitro‐groups in nanofilms. The detection and quantitative ‘reading’ of the influence of number of CV cycles were realized in the frame of a new error controllable approach that was applied for analysis of all available set of data. This approach includes in itself the following basic steps: (a) the procedure of the division (normalization) on the GC spectra, (b) the comparison of the smoothed spectra for their statistical proximity in the frame of the statistics of the fractional moments, (c) extraction of possible calibration parameters for possible calibration of the normalized spectra with respect to the number of CV cycles. These three basic steps are becoming effective for detection of the influence of some external factors. In our case it is important to detect the influence of the factor n characterizing CV cycles. 相似文献
116.
Enantiospecific Synthesis of (R)‐3‐Amino‐4‐(2,4,5‐trifluorophenyl)butanoic Acid Using (S)‐Serine as a Chiral Pool 下载免费PDF全文
Aytekin Köse Özlem Gündoğdu Derya Aktaş Meryem Fıstıkçı Ramazan Altundaş Hasan Seçen Yunus Kara 《Helvetica chimica acta》2015,98(2):260-266
Starting from (S)‐serine, a new method was developed for the synthesis of the β‐amino acid part of sitagliptin in ten steps and with an overall yield of 30%. The crucial step of the synthesis was the ring opening of N‐ and O‐protected (R)‐aziridin‐2‐methanol with (2,4,5‐trifluorophenyl)magnesium bromide to give N‐ and O‐protected (R)‐2‐amino‐3‐(2,4,5‐trifluorophenyl)propan‐1‐ol. 相似文献
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Summary In this paper we study some classes of Wiener functionals whose elements can be composed with a non-linear, non-absolutely continous transformation of the form of perturbation of identity in the direction of Cameron-Martin space. We show that under certain conditions the image of the Wiener measure under the above transformation induces a generalized Wiener functional on certain Sobolev spaces generalizing the Radon-Nikodym relation to non absolutely continuous transformations. A series representation for the generalized Radon-Nikodym derivative is presented and conditional expectations of some generalized random variables are considered. 相似文献
119.
Summary In this work we study the absolute continuity of the image of the Wiener measure under the transformations of the formT()=+u(), the shiftu is a random variable with values in the Cameron-Martin spaceH and is monotone in the sense that (T(+h-T(),h)
H
0 a.s. for allh inH. 相似文献
120.
Nanoscale Biodegradable Organic–Inorganic Hybrids for Efficient Cell Penetration and Drug Delivery 下载免费PDF全文
Sebastian Hörner Sascha Knauer Christina Uth Marina Jöst Dr. Volker Schmidts Dr. Holm Frauendorf Prof. Dr. Christina Marie Thiele Dr. Olga Avrutina Prof. Dr. Harald Kolmar 《Angewandte Chemie (International ed. in English)》2016,55(47):14842-14846
We report a comprehensive study on novel, highly efficient, and biodegradable hybrid molecular transporters. To this end, we designed a series of cell‐penetrating, cube‐octameric silsesquioxanes (COSS), and investigated cellular uptake by confocal microscopy and flow cytometry. A COSS with dense spatial arrangement of guanidinium groups displayed fast uptake kinetics and cell permeation at nanomolar concentrations in living HeLa cells. Efficient uptake was also observed in bacteria, yeasts, and archaea. The COSS‐based carrier was significantly more potent than cell‐penetrating peptides (CPPs) and displayed low toxicity. It efficiently delivered a covalently attached cytotoxic drug, doxorubicin, to living tumor cells. As the uptake of fluorescently labeled carrier remained in the presence of serum, the system could be considered particularly attractive for the in vivo delivery of therapeutics. 相似文献