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111.
Anna Giovanna Sciancalepore Elisa Mele Valentina Arcadio Francesco Reddavide Francesco Grieco Giuseppe Spano Patrick Lucas Giovanni Mita Dario Pisignano 《Food microbiology》2013
The development of fast, reliable and culture-independent molecular tools to detect bacteria producing biogenic amines deserves the attention of research and ultimately of the food industry in order to protect consumers' health. Here we present the application of a simple, low-cost, fast and sensitive method to perform microdroplet-based multiplex PCR, directly on a food matrix, for the simultaneous detection of bacterial genes involved in biogenic amine biosynthesis. After inoculating wine with Lactobacillus brevis IOEB 9809, cell lysis and DNA amplification are performed in one single step, without preliminary nucleic acid extraction or purification treatments. The assay is performed in about 30 min, requiring 150 nL of starting sample and it enables the detection of down to 15 bacterial cells. With respect to traditional culture techniques, the speed, the simplicity and the cheapness of this procedure allow an effective monitoring of microbial cells during food-making and processing. 相似文献
112.
Olga Leon Estrella Rogel Gustavo Torres Andres Lucas 《Petroleum Science and Technology》2013,31(7-8):913-927
ABSTRACT The electrophoretic mobilities of asphaltenes in n-heptane and ethanol were determined. The asphaltenes studied show a positive charge in both solvents. However, the magnitude of the charge is considerably lower in n-heptane than in ethanol. It is concluded that although the electrostatic forces are presented in both solvents, the van der Waals’ atractive forces are the main responsable for the flocculation of asphaltene particles. The addition of a well known asphaltene stabilizer, dodecyl benzene sulphonic acid (DBSA), decreases the electrophoretic mobility of asphaltene particles in ethanol until a constant positive value is reached. This means that the neutralization of the positive charges of the asphaltene particles is not complete, probably due to the limited adsorption of the DBSA on asphaltene surface and also, to the presence of charges inside the asphaltene particles that are not accessible to the DBSA. 相似文献
113.
114.
With the development of technologies and the fast increase of our population we will need to adjust the conventional electrical source to meet the continuous increasing demand. Since the energy cost as well as the environmental awareness is growing fast, technologies using renewable energies appear as an interesting alternative. The aim of this research is to present a solar-driven 30 kW LiBr/H2O single-effect absorption cooling system which has been designed and installed at Institut Universitaire Technologique of Saint Pierre. The first part of this article deals with the simulation of the solar thermal plant. A pilot plant has been setup as part of RAFSOL which is a research program managed by the national research agency (ANR). 相似文献
115.
A scientific application oriented classification for metal transfer modes in GMA welding 总被引:1,自引:0,他引:1
Américo Scotti Vladimir PonomarevWilliam Lucas 《Journal of Materials Processing Technology》2012,212(6):1406-1413
In this work, metal transfer in solid wire GMA welding was studied. Several experiments with different combinations of gas-wire-parameters were carried out to observe metal transfer and to characterize the various transfer modes. A laser shadograph system with synchronized electrical signals and high speed filming were used. New modes were observed and their particular characteristics described for completeness. A classification for metal transfer, oriented to scientific personnel (researchers, scholars and students), is proposed, in which the modes are independent of the type of shielding gas or welding power source. 相似文献
116.
Lucas. F.M. da Silva R.J.C. Carbas G.W. Critchlow M.A.V. Figueiredo K. Brown 《International Journal of Adhesion and Adhesives》2009,29(6):621-632
The single lap joint is the most studied type of adhesive joint in the literature. However, the joint strength prediction of such joints is still a controversial issue as it involves a lot of factors that are difficult to quantify such as the overlap length, the yielding of the adherend, the plasticity of the adhesive and the bondline thickness. The most complicated case is that where the adhesive is brittle and the overlap long. In any case, there is still a problem that is even more difficult to take into account which is the durability. There is a lack of experimental data and design criteria when the joint is subjected to high, low or variable temperature and/or humidity. The objective of this work is to carry out and quantify the various variables affecting the strength of single lap joints in long term, especially the effect of the surface preparation. The Taguchi method is used to decrease the number of experimental tests. The effect of material, geometry, surface treatment and environment is studied and it is shown that the main effect is that of the overlap length.In order to quantify the influence of the adhesive (toughness and thickness), the adherend (yield strength and thickness), the overlap, the test speed, the surface preparation and durability on the lap shear strength, the experimental design technique of Taguchi was used in the present study. An experimental matrix of 18 tests was designed and each test was repeated three times. The influence of the eight previously-mentioned variables could be assessed using the statistical software Statview®. In this paper a simple predictive equation is proposed for the design of single lap joints. 相似文献
117.
Anping Dong Lifeng Zhang Lucas N. W. Damoah 《JOM Journal of the Minerals, Metals and Materials Society》2011,63(1):23-27
In the current paper, different kinds of silicon wastes during the production of SoG-Si were summarized and the beneficial
analyses, such as financial value, energy value, CO2 emissions, and efficiency and energy payback time, were briefly discussed for the recycling of SoG-Si wastes. Possible technologies
to recycle and purify SoG-Si wastes were reviewed: such as filtration, sedimentation, solidification control, electromagnetic
separation, plasma oxidation, centrifugation, and high temperature remelting process, et al. 相似文献
118.
B. Lucas A. El Amrani M. Chakaroun B. Ratier R. Antony A. Moliton 《Thin solid films》2009,517(23):6280-11905
We have fabricated pentacene-based transistors on a transparent and flexible substrate made of polyethylene-terephthalate. We have shown that using an optical excitation at a wavelength of 365 nm photoconductivity modifies the carrier density without changing the mobility. The performance of the flexible organic phototransistors is mostly due to high-photosensitivity in the off-state with a ratio of photocurrent to dark current of about 2 104. Furthermore, the response times of the phototransistor are lower than 0.1 s. These results indicate that such transistors could be potentially used in photodetectors or amplifiers ordered by an optical gate. Moreover, we have noticed that there is no significant change in the mobility value when the transistor is bent in the direction of the current flow. 相似文献
119.
The inclusion of manganese-based single-molecule magnets (SMMs) into solvent cast films of poly(methyl methacrylate) (PMMA)
or polycarbonate (PC) was found to influence the thermal stability of these polymers. Examination of the thermal decomposition
profiles of PMMA films by thermo-gravimetric analysis (TGA) established that increasing weight % of SMM results in both enhancement
of the rate of decomposition initiated at “head-to-head” linkages along with suppression of the rate of decomposition initiated
at vinylidene chain ends. In the case of PC films, the temperature at which the primary thermal decomposition occurs decreases
with increasing weight % of SMM. The extent of these decomposition trends is correlated to the degree of SMM dispersal, as
studied by transmission electron microscopy (TEM). Favourable interactions between the ligands coordinated to the SMMs and
the polymer or solvent used in film preparation dictated the degree of SMM dispersal, with the ligand–polymer interactions
being dominant on the nano-length scale (1–100 nm) and ligand–solvent interactions being dominant on the micro-length scale
(>100 nm). 相似文献
120.
Haman JD Scripa RN Rigsbee JM Lucas LC 《Journal of materials science. Materials in medicine》2002,13(2):175-184
Calcium phosphate (CaP) coatings, from 40 000 to 200 000 nm thick, on titanium and titanium alloy substrates, were produced using radio frequency (RF) sputtering. Such coatings on dental implants have the potential for improving initial bone ingrowth rates. The success of these coatings may allow the movement from two stage implant systems to single stage implant systems, significantly reducing the time required for healing and fixture placement. Glass source materials were developed for the RF sputtering facility and the resultant coatings were characterized and compared to coatings sputtered from a conventional plasma sprayed hydroxyapatite (HA) source material. The coatings were characterized according to their chemistry, crystalline orientation, and residual strain. 相似文献