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61.
Flavio Cermola Marina DellaGreca Maria Rosaria Iesce Lucio Previtera Maria Rubino Fabio Temussi 《Journal of photochemistry and photobiology. A, Chemistry》2009,206(2-3):198-204
Irradiation of triazolo[4,3-a]pyridin-3-ones at 310 nm has been investigated in water/acetonitrile (7%). Cis-cisoid-fused cyclobutanes are generally obtained. Cage products are found starting from derivatives bearing (piperazin-1-yl)aryl moiety under dilute conditions (10−3 M). Two different routes appear to be involved in the formation of the observed photoproducts. A plausible mechanistic explanation is reported. 相似文献
62.
Mustazza C Borioni A Sestili I Sbraccia M Rodomonte A Ferretti R Del Giudice MR 《Chemical & pharmaceutical bulletin》2006,54(5):611-622
Some spiro[piperidine-4,2'(1'H)-quinazolin]-4'(3'H)-ones 3 and spiro[piperidine-4,5'(6'H)-[1,2,4]triazolo[1,5-c]quinazolines] 4 were synthesized and evaluated as ligands of the nociceptin receptor. The examined compounds showed partial agonistic activity, except compounds 3, 4n that proved to be pure antagonists. 相似文献
63.
64.
Malitesta C Mazzotta E Picca RA Poma A Chianella I Piletsky SA 《Analytical and bioanalytical chemistry》2012,402(5):1827-1846
This review highlights the importance of coupling molecular imprinting technology with methodology based on electrochemical
techniques for the development of advanced sensing devices. In recent years, growing interest in molecularly imprinted polymers
(MIPs) in the preparation of recognition elements has led researchers to design novel formats for improvement of MIP sensors.
Among possible approaches proposed in the literature on this topic, we will focus on the electrosynthesis of MIPs and on less
common hybrid technology (e.g. based on electrochemistry and classical MIPs, or nanotechnology). Starting from the early work
reported in this field, an overview of the most innovative and successful examples will be reviewed. 相似文献
65.
A semilinear parabolic transmission problem across either a fractal layer S or the corresponding prefractal layer Sh is studied. Local existence, uniqueness and regularity results for the mild solution, in both cases, are established as well as a sufficient condition on the initial datum for global existence is given. The asymptotic behaviour of the solutions of the approximating problems is studied. 相似文献
66.
In the last decade, the improved performance and versatility of the mass spectrometers together with the increasing availability of gene and genomic sequence database, led the mass spectrometry to become an indispensable tool for either protein and proteome analyses in cereals. Mass spectrometric works on prolamins have rapidly evolved from the determination of the molecular masses of proteins to the proteomic approaches aimed to a large-scale protein identification and study of functional and regulatory aspects of proteins. Mass spectrometry coupled with electrophoresis, chromatographic methods, and bioinformatics tools is currently making significant contributions to a better knowledge of the composition and structure of the cereal proteins and their structure-function relationships. Results obtained using mass spectrometry, including characterization of prolamins, investigation of the gluten toxicity for coeliac patients, identification of proteins responsible of cereal allergies, determination of the protein pattern and its modification under environmental or stress effects, investigation of genetically modified varieties by proteomic approaches, are summarized here, to illustrate current trends, analytical troubles and challenges, and suggest possible future perspectives. 相似文献
67.
Arrigo Scettri Rosaria Villano Patrizia Manzo Maria Rosaria Acocella 《Central European Journal of Chemistry》2012,10(1):47-53
The first Mukaiyama-Michael vinylogous reaction of a dioxinone-derived silyl ether to nitroalkenes is reported. The conjugate
addition is performed in absence of any catalyst under solvent-free conditions, proceeding with satisfactory efficiency with
variously substituted nitroalkenes. 相似文献
68.
69.
Ilaria Bonaduce Leslie Carlyle Maria Perla Colombini Celia Duce Carlo Ferrari Erika Ribechini Paola Selleri Maria Rosaria Tiné 《Journal of Thermal Analysis and Calorimetry》2012,107(3):1055-1066
This article presents a multi-analytical approach to investigating the drying, polymerisation and oxidative degradation of
linseed oil, which had undergone various treatments known to be undertaken during the nineteenth century in preparation for
painting. The oil was mechanically extracted from the same seed lot then processed by different methods: water washing, heat
treatments, and the addition of driers, with and without heat. The oil was prepared in 1999 within the framework of the MOLART
project. We compared thermogravimetric analysis (TG), which yields macromolecular information, with gas-chromatography mass-spectrometry
(GC/MS) and direct exposure mass spectrometry (DE-MS), which provide molecular information. This comparison enabled us to
elucidate the role of pre-treatment on the composition of the oil. TG and oxygen uptake curves registered at a constant temperature
helped us to identify the different physical behaviour of the oil samples, thus highlighting the presence of hydrolysed, oxidised
and crosslinked fractions, as a consequence of the different pre-treatments. GC/MS was used to characterise the soluble and
non-polymeric fraction of the oil, to calculate the ratios of palmitic to stearic acid (P/S), and azelaic to palmitic acid
(A/P), and to further evaluate the effects of oil pre-treatments. DE-MS using chemical ionisation with CH4, enabled us to establish the chemical composition of the oil in different stages of ageing. DE-MS proved to be a useful tool
for a simultaneous semi-quantitative characterisation of the free fatty acids, monoglycerids, diglycerides and triglycerides
present in each sample. The combination of thermal analysis with GC/MS and DE-MS enabled a model to be developed, which unravelled
how oil pre-treatments produce binders with different physical–chemical qualities. 相似文献
70.
Rosaria Conte Bruce Edmonds Scott Moss R. Keith Sawyer 《Computational & Mathematical Organization Theory》2001,7(3):183-205
A lengthy and intensive debate about the role of sociology in agent based social simulation dominated the email list simsoc@jiscmail.ac.uk during the autumn of 2000. The debate turned on the importance of models being devised to capture the properties of whole social systems and whether those properties should determine agent behaviour or, conversely, whether the properties of social systems should emerge from the behaviour and interaction of the agents and, if so, how that emergence should be represented. The positions of four of the main protagonists concerned specifically with the modelling issues are reprised and extended in this symposium. 相似文献