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101.
Marini A. Berbenni V. Bruni G. Villa M. Orlandi A. 《Journal of Thermal Analysis and Calorimetry》2002,68(2):389-396
GV150526A is a novel 2-carboxyindole derivative, recently synthesized by GlaxoWellcome, which is used in treatment or prevention
of CNS disorders resulting from neurotoxic damage. It has been prepared in three forms, F1, F2 and F3, having significantly
different hydration/dehydration behavior and/or diffraction patterns. Here, we extend the thermal analysis of these polymorphs
above 200°C, where all forms are fully dehydrated and the main thermal phenomena are decomposition and melting. Simultaneous
TG/DSC measurements have been repeated in wet and dry nitrogen atmospheres over a wide range of heating rates. Form F3 displays
a qualitatively different behavior relative to F1 and F2. This fact is interpreted as an evidence of a mechanism of decomposition
which sets F3 apart from F1 andF2. The thermal data are summarized by simple heuristic equations and few ‘apparent’enthalpies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
102.
Meloni S Palma A Schwartz J Kahn A Car R 《Journal of the American Chemical Society》2003,125(26):7808-7809
Metal organic contacts are at the basis of devices such as organic light emitting diodes (OLEDs). Here, we report a theoretical investigation of the chemical interaction between a Mg atom and an organic film made of tris(8-hydroxyquinoline)aluminum (Alq3) molecules. The latter is modeled either by an isolated molecule or by a bulk crystal. Using first-principles molecular dynamics for structural optimization, we find that an isolated Alq3 molecule and a Mg atom form an ion-pair. However, when the metal atom interacts with molecules in a bulk crystalline environment, we find that an organometallic complex is energetically preferred over the ion-pair. The complex formation is an effect of the environment which makes possible the interaction of the metal atom with several adjacent molecules. Here, our calculated O(1s) and N(1s) core level shifts agree well with recent experimental data on Alq3 films exposed to Mg. Our results resolve the apparent contradiction between experiment and predictions made in previous calculations in which a single Alq3 molecule was used to model a thin film. 相似文献
103.
Fernandez E Ford WT Qi N Read AL Smith JG Camporesi T De Sangro R Marini A Peruzzi I Piccolo M Ronga F Blume HT Hurst RB Venuti JP Wald HB Weinstein R Band HR Gettner MW Goderre GP Meyer OA Moromisato JH Polvado RO Shambroom WD Sleeman JC von Goeler E Ash WW Chadwick GB Clearwater SH Coombes RW Kaye HS Lau KH Leedy RE Lynch HL Messner RL Moss LJ Muller F Nelson HN Ritson DM Rosenberg LJ Wiser DE Zdarko RW Groom DE Lee HY Delfino MC Heltsley BK Johnson JR Lavine TL Maruyama T Prepost R 《Physical review letters》1985,54(11):1118-1121
104.
C. Pigot J.P. de Brion A. Caillet J.B. Cheze J. Derre G. Marel E. Pauli G. Vrana G. dAgostini G. Auriemma G. Marini G. Martellotti F. Massa A. Nigro A. Rambaldi A. Sciubba S. Reucroft E.G.H. Williams 《Nuclear Physics B》1985,249(1):172-188
The production of a strange dibaryonic system called H+1 (M = 2.13 GeV/c2, S = ?1), has been studied with a missing mass spectrometer, at the CERN Proton Synchrotron, in the reaction K?d → π?H+1 and in the line-reversed reaction π+d → K+H+1 between 0.9 and 1.4 GeV/c.The reactions , ,have been studied in a missing mass spectrometer at CERN. The experiment (PS159) is well adapted to search for a signal in the missing mass X+ (B = 2, S = ?1) produced in the backward c.m.s. direction, between 2.0 and 2.3 GeV/c2. The two reactions have been analysed at three different beam settings: 1.4, 1.06 and 0.92 GeV/c for reaction (1) and 1.4, 1.2 and 1.06 GeV/c for reaction (2). 相似文献
105.
Marcello Tiecco Lorenzo Testaferri Andrea Temperini Luana Bagnoli Francesca Marini Claudio Santi 《合成通讯》2013,43(12):2167-2179
Simple alkenes react with PhSeOTf and NaN3 in MeCN to afford β-phenylseleno azides as the result of a stereospecific trans addition. The regioselectivity of the process is determined by the structure of the alkene. 相似文献
106.
107.
In the course of our previous investigations, we dealt with the direct synthesis of unknown 1-aminopyrroie derivatives, obtained by reaction of some azoalkenes with B-diketones, 8- ketoesters, or B-ketoamides under copper (II) ionscatalysis. 1-9 相似文献
108.
Giovanna Bruni C. Milanese G. Bellazzi V. Berbenni P. Cofrancesco A. Marini M. Villa 《Journal of Thermal Analysis and Calorimetry》2007,89(3):761-766
The processes of production of drugs and dosage forms in the solid state often cause unwanted transformation of portions of
the substances into amorphous state, with significant changes of properties such as stability and bio-availability. When this
amorphous fraction is of the order of a few percent, it usually goes unnoticed, but it should be accurately determined within
a quality control system. In this work, we consider a model drug, perphenazine, where partial amorphisation may be induced
by standard mechanical treatments.
We show that Differential Scanning Calorimetry (DSC) leads to consistent estimations of the amorphous fractions induced by
the treatment. Furthermore, DSC also yields the expected amounts of amorphous perphenazine when analysing known mixtures of
perfectly crystalline samples (untreated) and partially amorphous samples (treated). We show that even amorphous fractions
of the order of 1% are accurately estimated by our method. 相似文献
109.
Francesca Leonelli Luisa Maria Migneco Alessio Valletta Rinaldo Marini Bettolo 《Molecules (Basel, Switzerland)》2021,26(9)
The scientific activity carried out over forty-five years on stemodane diterpenes and diterpenoids structure elucidation, biogenesis, biosynthesis, biological activity and biotransformations was reviewed. 相似文献
110.
Amedeo Altavilla 《复变函数与椭圆型方程》2015,60(1):59-77
The theory of slice regular functions over the quaternions, introduced by Gentili and Struppa in 2007, was born on balls centred in the origin and has been extended to more general domains that intersect the real axis in a work of 2009 in collaboration with Colombo and Sabadini. This hypothesis can be overcome using the theory of stem functions introduced by Ghiloni and Perotti in 2011, in the context of real alternative algebras. In this paper, I will recall the notion and the main properties of stem functions. After that I will introduce the class of slice regular functions induced by stem functions and, in this set, I will extend the identity principle, the maximum and minimum modulus principles and the open mapping theorem. Differences will be shown between the case when the domain does or does not intersect the real axis. 相似文献