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81.
Maulucci N De Riccardis F Botta CB Casapullo A Cressina E Fregonese M Tecilla P Izzo I 《Chemical communications (Cambridge, England)》2005,(10):1354-1356
The synthesis of a new class of amphiphilic calix[4]arene-based ionophores, relying on direct reductive amination as a key step, and the evaluation of their H+ and Na+ transporting properties is described. 相似文献
82.
The northern and southern polar oceans have very different oceanographic features. Taking advantage of the information available on haemoglobin structure and function, we analysed the evolutionary history of the alpha and beta globins of Antarctic and Arctic haemoglobins as a basis for reconstructing the phylogenetic relationships among species. 相似文献
83.
de Pasquale F Testa C Soldaini R Casieri C Podo F De Luca F 《Magnetic resonance imaging》2005,23(4):577-584
We propose an application of a Bayesian methodology to dynamic MR images of protons J-coupled to 13C nuclei for monitoring the in vivo 13C-glucose uptake of mouse brain. The very low population of these protons and the random noise make the analysis of these images extremely difficult. The proposed method restores the images and provides an "activation" map of the mouse brain by means of a hypothesis testing procedure. The restoration step is performed in the Bayesian framework so that among the other advantages of a stochastic approach, it is possible to model spatial and temporal information about neighboring pixels. This leads to a restoration procedure able to reduce the noise level while preserving the information about the edges of signal areas. Based on the restored images, the testing procedure provides us with a reliable map of pixels characterized by the 13C-glucose uptake. 相似文献
84.
Cinzia Bonotto Dr. 《ZDM》2001,33(3):75-84
In this paper we present an explorative study for which special cultural artifacts have been used, i.e. supermarket receipts, to try to construct with 9-year old pupils (fourth class of primary school) a new mathematical knowledge, i.e. the algorithm for multiplication of decimal numbers. Furthermore also estimation and approximation processes have been introduced, procedures that are not commonly used in ordinary teaching activity. In our study the receipts, through some modifications, have become more explicitly tools of mediation and integration between in and out-of school knowledge, so they can be utilized to create new mathematical goals, thus becoming real mathematizing tools and constituting a didactic interface between in and out-of-school mathematics. In agreement with ethnomathematical perspective we deem that it is a task for the teacher to know, in order to be able to profitably take account of the teaching, the life experienced by the pupil. Future mathematics teachers should be prepared a) to see mathematics incorporated into real world, b) to investigate mathematical ideas and practices of their pupils, and c) to look for ways to incorporate into the curriculum elements belonging to the sociocultural environment of the pupils, as a starting point for mathematical activities in the classroom. In this way the motivation, interest and curiosity of the pupils will be increased and the attitude towards mathematics of both pupils and teachers will be changed. 相似文献
85.
Valter Castelvetro Francesco Ciardelli Cinzia De Vita Antonio Puppo 《Macromolecular rapid communications》2006,27(8):619-625
Summary: The synthesis of aqueous dispersions of hybrid acrylic copolymer particles with either a monofunctional or a multifunctional polyhedral oligomeric silsesquioxane methacrylate comonomer has been performed by free radical heterophase polymerization. The miniemulsion process gives stable latexes, whereas the less controlled emulsion route results in colloidal instability of the products. The thermal and mechanical properties of the nanocomposite latex films have been preliminarily investigated.
86.
Summary: A comparative study of the performances of (bpzmp)ZrBz3 ( 1 ) and (hppzm)ZrBz3 ( 2 ) activated with B(C6F5)3 or [Ph3C][B(C6F5)4] in ethylene polymerisation pointed out that the steric properties of the metal complex and the boron activator affect the productivity of the catalyst and, more remarkably, the microstructure of the polyethylenes produced. A polymerisation mechanism accounting for these results has been proposed.
87.
Starting from a 3-dimensional projective space we construct divisible designs admitting GL(3,q) as an automorphism group. 相似文献
88.
Paola Vitale Cinzia D’Introno Filippo Maria Perna Maria Grazia Perrone Antonio Scilimati 《Tetrahedron: Asymmetry》2013,24(7):389-394
The use of microorganism growing cells is a well recognized methodology in biocatalyzed organic reactions. A non-conventional thermotolerant Kluyveromyces marxianus yeast strain was used for the bio-reduction of different arylketones. Differently substituted ketones were converted into the corresponding (S)-alcohols with up to 96% enantiomeric excess under very mild reaction conditions. Kluyveromyces marxianus represents a promising biocatalyst for the production of optically active 1-arylethanols. 相似文献
89.
Dr. Quentin Simon Dr. Davide Barreca Dr. Alberto Gasparotto Dr. Chiara Maccato Prof. Eugenio Tondello Dr. Cinzia Sada Dr. Elisabetta Comini Prof. Giorgio Sberveglieri Dr. Manish Banerjee Dr. Ke Xu Prof. Anjana Devi Prof. Roland A. Fischer 《Chemphyschem》2012,13(9):2342-2348
CuO/ZnO nanocomposites were synthesized on Al2O3 substrates by a hybrid plasma‐assisted approach, combining the initial growth of ZnO columnar arrays by plasma‐enhanced chemical vapor deposition (PE‐CVD) and subsequent radio frequency (RF) sputtering of copper, followed by final annealing in air. Chemical, morphological, and structural analyses revealed the formation of high‐purity nanosystems, characterized by a controllable dispersion of CuO particles into ZnO matrices. The high surface‐to‐volume ratio of the obtained materials, along with intimate CuO/ZnO intermixing, resulted in the efficient detection of various oxidizing and reducing gases (such as O3, CH3CH2OH, and H2). The obtained data are critically discussed and interrelated with the chemical and physical properties of the nanocomposites. 相似文献
90.
Since Markowitz (1952) formulated the portfolio selection problem, many researchers have developed models aggregating simultaneously several conflicting attributes such as: the return on investment, risk and liquidity. The portfolio manager generally seeks the best combination of stocks/assets that meets his/her investment objectives. The Goal Programming (GP) model is widely applied to finance and portfolio management. The aim of this paper is to present the different variants of the GP model that have been applied to the financial portfolio selection problem from the 1970s to nowadays. 相似文献