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101.
A. N. Karpov D. V. Marin V. A. Volodin J. Jedrzejewski G. A. Kachurin E. Savir N. L. Shwartz Z. Sh. Yanovitskaya I. Balberg Y. Goldstein 《Semiconductors》2008,42(6):731-736
Deposition of SiO x layers of variable composition onto silicon wafers was performed by co-sputtering of spaced Si and SiO2 targets in argon plasma. Coordinate dependences of the thickness and refractive index of separately deposited Si and SiO2 layers and the SiO x layer grown during co-sputtering of targets were determined using optical techniques. It was shown that the SiO x layer composition is not equal to a simple sum of thicknesses of separately deposited Si and SiO2 layers. The coordinate dependences of the Si and SiO2 layer thicknesses were calculated. To fit the calculated and experimental data, it is necessary to assume that no less than 10% of silicon is converted to dioxide during co-sputtering. A comparison of the coordinate dependences of the IR absorbance in SiO2 and SiO x layers with experimental ellipsometric data confirmed the presence of excess oxygen in the SiO x layer. Taking into account such partial oxidation of sputtered silicon, composition isolines in the substrate plane were calculated. After annealing of the SiO x layer at 1200°C, photoluminescence was observed in a wafer area predicted by calculations, which was caused by the formation of quantum-size Si nanocrystallites. The photoluminescence intensity was maximum at x = 1.78 ± 0.3, which is close to the composition optimum for ion-beam synthesis of nanocrystals. 相似文献
102.
G. A. Kachurin S. G. Cherkova V. A. Volodin D. V. Marin M. Deutschmann 《Semiconductors》2008,42(2):183-187
The effect of high-power nanosecond (20 ns) and femtosecond (120 fs) laser pulses on silicon nanostructures produced by ion-beam-assisted synthesis in SiO2 layers or by deposition onto glassy substrates is studied. Nanosecond annealing brings about a photoluminescence band at about 500 mn, with the intensity increasing with the energy and number of laser pulses. The source of the emission is thought to be the clusters of Si atoms segregated from the oxide. In addition, the nanosecond pulses allow crystallization of amorphous silicon nanoprecipitates in SiO2. Heavy doping promotes crystallization. The duration of femtosecond pulses is too short for excess Si to be segregated from SiO2. At the same time, such short pulses induce crystallization of Thin a-Si films on glassy substrates. The energy region in which crystallization is observed for both types of pulses allows short-term melting of the surface layer. 相似文献
103.
Teresa Ortega Elena De La Hera M. Emilia Carretero Pilar Gómez-Serranillos M. Victoria Naval Angel M. Villar Marin Prodanov Visitación Vacas Teresa Arroyo Teresa Hernández Isabel Estrella 《European Food Research and Technology》2008,227(6):1641-1650
Red wine has been reported to exert beneficial effects in preventing cardiovascular diseases probably due to their polyphenols
constituents. The vasorelaxant capacity and phenolic composition of four monovarietal young red wines Merlot, Tempranillo,
Garnacha and Cabernet-Sauvignon obtained from grapes from 2004 vintage, cultivated under the same climatic and agricultural
conditions, wine-making technology and storage conditions, were determined using vascular reactivity assay in rat aortic and
high-performance liquid chromatography, respectively. Primary cultures of vascular smooth muscle cells from Wistar rats were
also used to evaluate their survival prevention activity as well. Every studied wine present vasorelaxation effect, but the
higher value corresponds to the analyzed Merlot wine, especially rich in phenolic compounds, mainly catechins and oligomeric
proanthocyanidins and anthocyanin glycosides. This study further demonstrated previous investigations about the phenolic composition
of wines relation with their vasorelaxation activity. 相似文献
104.
Estimation of physical and mechanical properties of agro-based particleboards by near infrared spectroscopy 总被引:2,自引:1,他引:1
Paulo Ricardo Gherardi Hein Ana Carolina Maioli Campos Rafael Farinassi Mendes Lourival Marin Mendes Gilles Chaix 《Holz als Roh- und Werkstoff》2011,69(3):431-442
Partial least square regression (PLS-R) calibrations based on near infrared (NIR) spectroscopic data were developed in order to predict mechanical and physical properties of agro-based particleboards. The panels were manufactured using Eucalyptus and Pinus wood particles and sugar cane bagasse. The following panel properties were evaluated according to standard methods: modulus of elasticity (MOE), modulus of rupture (MOR), internal bonding (IB) strength, water absorption (WA24H), and thickness swelling (TS24H) after 24 hours of immersion. NIR spectra information was measured on samples cut from each particleboard and correlated with their physical and mechanical properties by PLS-R to build predictive NIR models. The NIR models for IB, WA24H and TS24H presented satisfactory coefficient of determination (0.73; 0.72 and 0.75, respectively.) The key role of resins (adhesives), cellulose, and lignin for NIRS calibrations of mechanical and physical properties of the particleboards is shown. These models can be useful to quickly verify such properties in unknown agro-based particleboards. 相似文献
105.
Ahmed Bazil Taha Carreras Darío Castro Marin Eduardo Garcia 《Wireless Personal Communications》2021,117(4):2757-2780
Wireless Personal Communications - Semantic Web content extracting are the augmentation of the present web where the data is given in the better importance and allowing users to work close by close... 相似文献
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108.
This paper proposes a stochastic scheduling model to determine optimal operation of generation and storage units of a virtual power plant (VPP) for participating in a joint energy and regulation service (RS) market under uncertainty. Beside electricity, the VPP provides required RSs according to the probability of delivery request in the electricity market. A new model for providing RS is introduced in which the dispatchable generation units are financially compensated with their readiness declarations and will be charged/paid for their real‐time down/up regulations. Besides, the VPP sets up incentive price‐quantity curves to benefit from the potential of demand side management in both energy and RS market. Within the model presented here, the VPP consists of two types of generation units: wind turbine and standby diesel generator; the latter is modeled by considering CO2‐emission penalty costs. The given uncertainties are divided into two parts. Firstly, the uncertainties from the energy market price are simulated using information gap decision theory to evaluate the risk‐based resource scheduling for both risk‐taker and risk‐averse VPP. Other uncertainties affecting decision making such as wind turbine generation, load, regulation up/down calling probabilities, and regulation market prices are modeled via scenario trees. Three typical case studies are implemented to validate the performance and effectiveness of the proposed scheduling approach. 相似文献
109.
Jennifer Pasquier Damien Rioult Nadine Abu-Kaoud Jessica Hoarau-Véchot Matthieu Marin Frank Le Foll 《International journal of molecular sciences》2015,16(7):14318-14337
The regulation of cell volume is an essential function that is coupled to a variety of physiological processes such as receptor recycling, excitability and contraction, cell proliferation, migration, and programmed cell death. Under stress, cells undergo emergency swelling and respond to such a phenomenon with a regulatory volume decrease (RVD) where they release cellular ions, and other osmolytes as well as a concomitant loss of water. The link between P-glycoprotein, a transmembrane transporter, and cell volume regulation is controversial, and changes in cells volume are measured using microscopy or electrophysiology. For instance, by using the patch-clamp method, our team demonstrated that chloride currents activated in the RVD were more intense and rapid in a breast cancer cell line overexpressing the P-glycoprotein (P-gp). The Cell Lab Quanta SC is a flow cytometry system that simultaneously measures electronic volume, side scatter and three fluorescent colors; altogether this provides unsurpassed population resolution and accurate cell counting. Therefore, here we propose a novel method to follow cellular volume. By using the Coulter-type channel of the cytometer Cell Lab Quanta SC MPL (multi-platform loading), we demonstrated a role for the P-gp during different osmotic treatments, but also a differential activity of the P-gp through the cell cycle. Altogether, our data strongly suggests a role of P-gp in cell volume regulation. 相似文献
110.
Andrya L. Whitten Jose R. Marin Jarrin A. Scott McNaught 《Journal of Great Lakes research》2018,44(1):105-113
Dreissenid mussels are known to disrupt the base of the food web by filter feeding on phytoplankton; however, they may also directly ingest zooplankton thereby complicating their effects on plankton communities. The objective of this study was to quantify the effects of quagga mussel feeding on the composition and size structure of Lake Michigan zooplankton assemblages. Two mesocosm (six 946 L tanks) experiments were conducted in summer 2013, using quagga mussels and zooplankton collected near Beaver Island, MI, to examine the response of zooplankton communities to the presence and absence of mussels (experiment 1) and varying mussel density (experiment 2). Mesocosms were sampled daily and zooplankton taxa were enumerated and sized using microscopy and FlowCAM® imaging. In experiment 1, the presence of quagga mussels had a rapid negative effect on veliger and copepod nauplii abundance, and a delayed negative effect on rotifer abundance. In experiment 2, mussel density had a negative effect on veliger, nauplii, and copepodite abundance within 24 h. Multivariate analyses revealed a change in zooplankton community composition with increasing mussel density. Ten zooplankton taxa decreased in abundance and frequency as quagga mussel density increased: except for the rotifer Trichocerca sp., treatments with higher mussel densities (i.e., 1327, 3585, and 5389 mussels/m2) had the greatest negative effect on small-bodied zooplankton (≤ 128 μm). This study confirms results from small-scale (≤ 1 L) experiments and demonstrates that quagga mussels can alter zooplankton communities at mesoscales (~ 1000 L), possibly through a combination of direct consumption and resource depletion. 相似文献