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31.
32.
Solubility‐Limited Extrinsic n‐Type Doping of a High Electron Mobility Polymer for Thermoelectric Applications 下载免费PDF全文
33.
34.
Fulvio Corrandini Andrea Marchetti Mara Tagliazucchi Lorenzo Tassi Giuseppe Tosi 《加拿大化工杂志》1993,71(1):124-129
Kinematic viscosity data (ν) are presented for ethane-1,2-diol, for N, N-dimethylformamide and for nine binary mixtures in the - 10°C to 80°C temperature range. The experimental data were fitted by several empirical relations such as Grunberg-Nissan (1949), McAllister (1960), Heric (1966), Lobe (1973), Auslander (1964) and polynomial equations. Some considerations regarding the meaning of the obtained adjustment parameters are made. Furthermore, a new best fit equation is proposed and its validity has been compared to that of the other relations on the basis of the reproducibility of the experimental data. 相似文献
35.
Guastavino F. Coletti G. Torello E. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2005,12(3):524-529
This work is related to a medium term research program which aims at studying the behaviour of twisted pair specimens of enamelled copper wires subjected to high frequency sinusoidal voltage waveforms which are used in some advanced types of electrical machines. High frequency voltages due to, for instance, converter operation are not considered in this paper. The following test conditions were adopted: different voltage amplitudes up to 2 kV, selected voltage frequencies up to 5 kHz and test temperatures up to 200 /spl deg/C. The experimental work aims at defining reference-testing procedures and at studying the aging process of enamelled wires which are usually employed in random windings of electrical machines. As final result, a phenomenological model of the aging process, acting in the considered insulation system, is obtained and it is accurately defined on the grounds of the output data. The type of test method adopted and the type of data processing appear worthy to be used in order to characterize enamelled wires in terms of thermoelectrical degradation processes in presence of partial discharges. 相似文献
36.
A modelling methodology and a tool that supports the analyst in contexts characterized by a multiplicity of actors and information sources and a limited or absent interaction are presented in this paper. In these situations Problem Formulation becomes the first essential aim of a technical intervention applied to acquire, organize, present and reorganize knowledge of the action system, at both an individual and collective level; Model Structuring and Processing are strictly related in the same global approach. The basic structure of a prototype system, designed to assist the analyst in the structuring and then in the “critical reading process”, is also presented. 相似文献
37.
Fulvio Mattivi 《European Food Research and Technology》1993,196(6):522-525
Some recent studies have put forward the hypothesis that the presence oftrans-resveratrol (trans-3,5,4′-trihydroxystilbene) in red wine may be related to some of its therapeutic properties. A fundamental step in view of this evaluation is the development of a method for the quick, accurate and precise analysis of this compound. Sample enrichment and purification can be obtained by solid-phase extraction using reverse-phase C18 cartridges. HPLC analysis carried out by means of a photodiode-array detector, with an internal standard method, allows the detection of up to 10 μg/L in wine, with a linear range between 0.6 and 300 ng injected and a precision of 3.3%. The results of the first analyses show that the concentrations oftrans-resveratrol in wines might be much higher than so far reported in the literature. 相似文献
38.
Fulvio Ananasso Giorgio Lo Verde 《International Journal of Satellite Communications and Networking》1995,13(1):11-29
The scope of this paper is to present the status and the preliminary results of the research activities that Telespazio is carrying out with the aim at identifying the role of the VSAT systems in the advanced telecommunications services, which will be dominant in the second half of nineties and beyond. The first part of the paper is devoted to an overview of the evolution trend of the terrestrial networks. The main body of the paper presents the results of our investigations on the application of VSAT systems in two fields: broadband networks and intelligent networks. Background information has been intentionally added for the easier comprehension of the topics presented in the paper. A list of acronyms appears as an Appendix. 相似文献
39.
The use of iodine staining for the quantitative analysis of lipids separated by thin layer chromatography 总被引:2,自引:0,他引:2
The method described for quantitative estimation of lipids separated on thin layer chromatography plates exploits the observation
that most lipids can be stained by iodine vapor and that, in “controlled” conditions, the intensity of this staining is proportional
to the actual amount of lipid in the spot. The method consists of i) exposing the developed plate to iodine vapor; ii) spraying
it with a suitable solvent to prevent halogen evaporation; iii) collecting the stained lipids by scraping the spots off the
plate; and iv) determining by a rate-sensing method the absorbed iodine. The final determination is performed by measuring
spectrophotometrically (at 410 nm) the rate of decolorization of a solution of Ce(IV) by As(III) in strong acidic conditions.
The reaction rate, which is positively related to the concentration of iodine, is derived from the slope of the absorbance
change plotted vs time.
Providing that standards and samples are stained simultaneously, a quantitative estimation of lipid components of a mixture
is possible in a reasonable time with excellent accuracy and reproducibility. In our hands, the method has been successfully
applied to several common phospholipids, long chain fatty acids, cholesterol and deoxycholate, and triacylglycerols, in the
range of 5–60 μg. 相似文献
40.
Emanuela Stampone Debora Bencivenga Clementina Barone Marilena Di Finizio Fulvio Della Ragione Adriana Borriello 《International journal of molecular sciences》2021,22(14)
p57Kip2 protein is a member of the CIP/Kip family, mainly localized in the nucleus where it exerts its Cyclin/CDKs inhibitory function. In addition, the protein plays key roles in embryogenesis, differentiation, and carcinogenesis depending on its cellular localization and interactors. Mutations of CDKN1C, the gene encoding human p57Kip2, result in the development of different genetic diseases, including Beckwith–Wiedemann, IMAGe and Silver–Russell syndromes. We investigated a specific Beckwith–Wiedemann associated CDKN1C change (c.946 C>T) that results in the substitution of the C-terminal amino acid (arginine 316) with a tryptophan (R316W-p57Kip2). We found a clear redistribution of R316W-p57Kip2, in that while the wild-type p57Kip2 mostly occurs in the nucleus, the mutant form is also distributed in the cytoplasm. Transfection of two expression constructs encoding the p57Kip2 N- and C-terminal domain, respectively, allows the mapping of the nuclear localization signal(s) (NLSs) between residues 220–316. Moreover, by removing the basic RKRLR sequence at the protein C-terminus (from 312 to 316 residue), p57Kip2 was confined in the cytosol, implying that this sequence is absolutely required for nuclear entry. In conclusion, we identified an unreported p57Kip2 NLS and suggest that its absence or mutation might be of relevance in CDKN1C-associated human diseases determining significant changes of p57Kip2 localization/regulatory roles. 相似文献