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排序方式: 共有850条查询结果,搜索用时 31 毫秒
161.
162.
The Mediterranean Diet decreases LDL atherogenicity in high cardiovascular risk individuals: a randomized controlled trial
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Álvaro Hernáez Olga Castañer Alberto Goday Emilio Ros Xavier Pintó Ramón Estruch Jordi Salas‐Salvadó Dolores Corella Fernando Arós Lluis Serra‐Majem Miguel Ángel Martínez‐González Miquel Fiol José Lapetra Rafael de la Torre M. Carmen López‐Sabater Montserrat Fitó 《Molecular nutrition & food research》2017,61(9)
163.
Abstract The Morlet wavelet spectrum of the radiation emitted by a two level atom in presence of two laser pulses with very close frequency is obtained. The wavelet spectrum gives information on the time evolution of the full spectrum and of a particular line. The beating condition stimulates the atom to emit pulses of harmonics with duration of the order of a few optical cycles of the pumping radiation. Pulse trains of 3 optical cycles (FWHM) are observed. 相似文献
164.
Jean-Yves Colle Emilio A. Maugeri Catherine Thiriet Zeynep Talip Franco Capone Jean-Pol Hiernaut 《Journal of Nuclear Science and Technology》2013,50(5):700-711
A new system has been developed to determine absolute quantities of gas (mainly noble gases) released during thermal desorption in the range from 10?12 to 10?5 mol with a precision of few percent. The system is actually designed for simultaneous measurement of gaseous elements like He, Xe, Kr, thermally released from nuclear fuel samples and also allows the determination of the release kinetics as a function of time. This system, called Quantitative GAs MEasurement System (Q-GAMES), is based on the principle of collecting, purifying and spiking the sample gas in a “high-pressure” chamber, and continuous sampling of the gas for mass spectrometric analysis without sample depletion during the experiment. It is equipped with its own spike generator and with different gas purification systems. It is shown that this system fulfills the requirement to work with two existing very high-temperature gas desorption facilities for nuclear materials. This paper describes the Q-GAMES principle, the spiking system, its calibration, its operative mode, the different quantification techniques, as well as its technical data, in combination with some examples of typical application. 相似文献
165.
Radiation synthesis of a thermo-pH responsive binary graft copolymer (PP-g-DMAEMA)-g-NIPAAm by a two step
method 总被引:1,自引:1,他引:0
Summary (PP-g-DMAEMA)-g-NIPAAm was synthesized using gamma radiation from a 60Co
source. Graft polymerization of N,N’-dimethylaminoethylmethacrylate (DMAEMA) onto polypropylene (PP)
was accomplished in about 100 percent yield by the mutual irradiation technique at a dose of 10 kGy.
Grafting of N-isopropylacrylamide (NIPAAm) onto PP-g-DMAEMA was carried out by the pre-irradiation method
with doses from 20 to 100 kGy. The influence of temperature, reaction time, and monomer concentration
on grafting yield was studied. Grafting processes were confirmed by infrared spectroscopy (FTIR-ATR).
(PP-g-DMAEMA)-g-NIPAAm films were characterized by thermogravimetric analysis (TGA) and differential
scanning calorimetry (DSC). The lower critical solution temperature (LCST) and critical pH point of
the films were obtained by water contact angle and percent swelling measurements. The LCST was also
determined by DSC. We report here hare a new binary graft copolymer which shows two LCST values, synthesized
in two steps. 相似文献
166.
G Stoica I Castelló Serrano A Figuerola I Ugarte R Pacios E Palomares 《Nanoscale》2012,4(17):5409-5419
Quantum dot-hydrotalcite layered nanoplatforms were successfully prepared following a one-pot synthesis. The process is very fast and a priori delamination of hydrotalcite is not a prerequisite for the intercalation of quantum dots. The novel materials were extensively characterized by X-ray diffraction, thermogravimetry, infrared spectroscopy, transmission electron microscopy, true color fluorescence microscopy, photoluminescence, and nitrogen adsorption. The quantum dot-hydrotalcite nanomaterials display extremely high stability in mimicking physiological media such as saline serum (pH 5.5) and PBS (pH 7.2). Yet, quantum dot release from the solid structure is noted. In order to prevent the leaking of quantum dots we have developed a novel strategy which consists of using tailor made double layered hydrotalcites as protecting shells for quantum dots embedded into silica nanospheres without changing either the materials or the optical properties. 相似文献
167.
Emilio Alvarez-Parrilla Laura A. de la Rosa Ryszard Amarowicz Fereidoon Shahidi 《Food chemistry》2012
The potential of fresh and processed Jalapeño and Serrano pepper extracts for the control of lipid oxidation in several systems was investigated. The assays used included β-carotene/linoleate model system, striped corn oil, ground pork meat and Cu(II)-induced oxidation of human low-density lipoprotein (LDL). The results showed that all extracts were effective in at least one system, although their potency varied. Extracts of smoked Jalapeño were particularly effective. The lipid-protective effect of the extracts was mainly due to the presence of phenolic compounds, but other phytochemicals, such as chlorophylls were also involved. 相似文献
168.
169.
Antonio Valentoni Sebastiano Garroni Claudio Pistidda Elisabetta Masolo Emilio Napolitano Pietro Moretto Martin Dornheim Gabriele Mulas Stefano Enzo 《International Journal of Hydrogen Energy》2014
In situ two-dimensional synchrotron X-ray powder diffraction investigation combined with Rietveld method data analysis were performed in order to yield a complete and quantitative phases structure evolution of the polycrystalline mixture 2LiNH2 + KBH4 + LiH during H2 desorption. While a first-principles, purely thermodynamics approach of the system predicted a single dehydrogenation step reaction at relatively low temperatures, it is assessed experimentally that the reaction occurs in two steps with first the formation of Li2NH at ca. 230 °C due to the reaction between LiNH2 and LiH plus hydrogen and ammonia evolution, followed by an additional reaction of the resulting phases with KBH4 at 360 °C, which releases hydrogen and leads to the formation of the monoclinic and tetragonal Li3BN2 polymorphs. Besides pointing out possible limits of a purely thermodynamics approach inevitably relying exact knowledge of experimental quantities, it is concluded that before assuming it viable for on-board vehicle use, additional stoichiometries may be worth of investigation in order to assess any existence of lower hydrogen desorption temperature of such system. 相似文献
170.
L. Emilio Morales Garry Griffith Victor Wright Euan Fleming Wendy Umberger Nam Hoang 《Meat science》2013
Australian beef consumers have different preferences given their characteristics and the effect on expected quality of cues related to health, production process and eating experience. Beef brands using Meat Standards Australia (MSA) grades can help to signal quality and reduce consumers' uncertainty when shopping. The objective of this study is to identify the characteristics of beef buyers and their perceptions about product attributes that affect the propensity to buy branded beef. Binary logistic models were applied identifying differences between all respondents and the potential target market, including buyers in medium to high income segments, and between buyers in the target market who would buy branded beef for taste and health reasons. Variables increasing the propensity to buy branded beef include previous experience, appreciation for branded cuts and concern about quality more than size. Finally, variations in preferences for marbling and cut were found between buyers who would buy branded beef for taste and health reasons. 相似文献