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101.
102.
Gian Piero Celata Francesco Dannibale Andrea Chiaradia Maurizio Cumo 《International Journal of Heat and Mass Transfer》1998,41(24):396
The present work deals with the results of an experimental investigation on heat transfer in water cooled vertical pipes, for thermal–hydraulic conditions ranging from forced convective flow to mixed convective flow. The flow of water in the pipe is upwards.Experimental data confirm the reduction in the heat transfer rate for mixed convection in upward heat flow, mainly due to the laminarization effect in the near-wall region (buoyancy effect) . They are in a very good agreement with numerical methods, such as the k–-model.A new method for the calculation of the heat transfer coefficient in upward mixed convection heated flow is proposed. It is based on the well-known superposition method (heated downflow) modified accounting for the phenomenology of the upward heated flow in comparison with downflow heated conditions. 相似文献
103.
Maurizio Penco Arifur RhamanGloria Spagnoli Gerardus JanszenLuca Di Landro 《Materials Letters》2011,65(14):2107-2110
Self-healing behavior of ionomer blends containing both rapidly crystallizing phase and with higher amount of amorphous phase has not yet been studied. This work gives a new insight to understand the development of materials with intrinsic self-healing property. In particular, binary blends based on poly(ethylene-co-methacrylic acid sodium salt) (EMNa)/Poly(vinyl alcohol-co-ethylene) (EVA) and epoxidized natural rubber (ENR), were studied by ballistic puncture tests. In the composition range explored (15-50 wt.% of EVA and ENR), the self-healing characteristics decrease with the increasing amount of EVA but are maintained in all ranges for ENR/EMNa blends. The ballistic damage initiated autonomous healing was observed by optical microscopy and the healing was further analyzed by thermal and mechanical behaviors of the blend materials. 相似文献
104.
Maurizio Salato 《电子产品世界》2014,(9)
今天,服务器群的电力需求从早年的1kW/机架增加到了20kW。数据流量趋势正在加速,预计在不久的将来需求将达到30kW/机架。48V DC配电提供了一个可以随着服务器部署规模提升的高功率密度。 相似文献
105.
Fabrizio De MattiaIlaria Bruni Andrea GalimbertiFrancesca Cattaneo Maurizio CasiraghiMassimo Labra 《Food research international (Ottawa, Ont.)》2011,44(3):693-702
The objective of the present work is to evaluate the efficacy of a DNA barcoding approach as a tool for the recognition of commercial kitchen spices belonging to the Lamiaceae family that are usually sold as enhancers of food flavor. A total of 64 spices samples, encompassing six different genera (i.e. Mentha, Ocimum, Origanum, Salvia, Thymus and Rosmarinus) were processed with a classical DNA barcoding approach by amplifying and sequencing four candidate barcode regions (rpoB, rbcL, matK and trnH-psbA) with universal primers. Results suggest that the non-coding trnH-psbA intergenic spacer is the most suitable marker for molecular spices identification followed by matK, with interspecific genetic distance values ranging between about 0% to 7% and 0% to 5%, respectively. Both markers were almost invariably able to distinguish spices species from closest taxa with the exclusion of samples belonging to the genus Oregano. Moreover, in a context of food traceability the two markers are useful to identify commercial processed spice species (sold as dried plant material). We also evaluated the potential benefits of a multilocus barcode approach over a single-marker and although the most suitable combination was the matK + trhH-psbA, the observed genetic distances values were very similar to the discriminatory performance of the trnH-psbA. Finally, this preliminary work provide clear evidences that the efficacy of a DNA barcoding approach to the recognition of commercial spices is biased by the occurrence of taxonomic criticisms as well as traces of hybridization events within the family Lamiaceae. For this reason, to better define a more practical and standardized DNA barcoding tool for spices traceability, the building of a dedicated aromatic plants database in which all species and cultivars are described (both morphologically and molecularly) is strongly required. 相似文献
106.
In this paper we are concerned with networks obtained by connecting independent sources, linear resistors and non‐linear ideal op amps. A necessary and sufficient condition for the existence and uniqueness of solutions for every positive output saturation voltage of the op amps and every value of the independent sources is found. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
107.
Maurizio Martina Guido Masera Gianluca Piccinini Maurizio Zamboni 《The Journal of VLSI Signal Processing》2003,35(2):137-153
This paper proposes two JPEG 2000 compliant architectures: one for DWT (Discrete Wavelet Transform) and one for IWT (Integer Wavelet Transform) implementation. First of all some theoretical issues about DWT and IWT are discussed, then, starting from transforms characteristics, the architectures are presented showing both performance and cost. In the literature many DWT architectures have been proposed; our implementation is a new architecture that computes the DWT using filters of interest for the forthcoming JPEG 2000 standard. Moreover, we propose a Lifting Scheme based architecture for IWT, JPEG 2000 compliant too. The proposed architectures are able to support real-time streams: the DWT one, which is made of 20,000 cells, with an input throughput of 160 Msamples per second and a clock frequency of 160 MHz, the IWT one, consisting of 50,000 cells, with an input throughput of 4.5 Msamples per second and an internal clock frequency of 108 MHz. 相似文献
108.
Maurizio Penco Luciana Sartore Fabio Bignotti Stefania Della Sciucca Vittorio Ferrari Paolo Crescini Salvatore D'Antone 《应用聚合物科学杂志》2004,91(3):1816-1821
The aim of this work was the development of materials to be used in the field of gas sensing for the detection of organic vapors. Conductive sensors were prepared with carbon black filled blends of poly(vinyl chloride) and diol‐terminated poly(?‐caprolactone), an oligomeric plasticizer. For comparison, blends with di(2‐ethylhexyl)phthalate, a traditional low‐molecular‐weight plasticizer, were also prepared. All sensors were tested upon exposure to different organic vapors. In general, the plasticizer content affected the response rates of the sensors, and a linear variation of the relative resistance with the analyte concentration was observed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1816–1821, 2004 相似文献
109.
Maurizio Bianchi Federico Ferioli Massimiliano Petracci Maria Fiorenza Caboni Claudio Cavani 《European Food Research and Technology》2009,229(2):339-348
The influence of dietary lipid source [animal fats (AF) and vegetable oils (VO)] on quality characteristics of raw chicken
meat (breast, thigh and meat batter) and cooked breaded patties prepared using a conventional technology (CT; forming, battering,
breading, frying and convection cooking) or innovative technology (IT; forming, pre-dusting, steam cooking, battering and
frying) was evaluated. Overall, dietary lipid source did not influence the chemical composition of raw meat while it modified its colour (L*, a*, b*). With respect to AF, VO produced higher breast and thigh meat cooking losses as well as a lower moisture and
higher protein content of cooked breaded patties. VO also determined an increase of polyunsaturated-to-saturated fatty acid
ratio of both raw and processed meat. Despite the different fatty acid profiles, the oxidative status of lipids was not affected
by dietary lipid source and was acceptable in both raw meat and cooked patties as indicated by peroxide and thiobarbituric
acid reactive substance values. As for the processing technology, IT determined a higher moisture and lower lipid content
of the cooked breaded patties. Moreover, lipolysis degree was slightly higher in the products coming from IT. Finally, patties
from AF group were lighter and more yellow than products belonging to VO group whereas IT led to lighter, less red and more
yellow patties in comparison to CT. 相似文献
110.
Summary This paper analyzes Internet diffusion among various organizations, based on daily observation of second- level domain name
registrations under the “.it”ccTLD. In particular, we analyzed domain names registered by organizations in the non-profit
sector.<span style='font-size:12.0pt;mso-ansi-language: HU'>The penetration rate, calculated according to the number of organizations,
was computed for various widely separated geographic levels (regions). A concentration analysis was performed in order to
determine whether the geographical distribution of Internet use in Italy is less concentrated with respect to both the number
of existing institutions and income distribution, suggesting a diffusive effect.<span lang=EN-US style='font-size:12.0pt;
mso-ansi-language:EN-US'>Regression analysis was performed using demographic, social, economic and infrastructure indicators.
Results show that<span style='font-size:12.0pt;mso-ansi-language:HU'>a “social digital divide”exists, both in terms of geographical
distribution (i.e., in macro-areas - Northern, Central, and Southern Italy - and at the regional level) and in terms of the
legal status of the organizations, and that this digital divide will probably decrease in the future. 相似文献