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排序方式: 共有549条查询结果,搜索用时 31 毫秒
451.
452.
Giacomo Roncallo Gabriele Cacciamani Erica Vacchieri Mariia Ilatovskaia Ivan Saenko Olga Fabrichnaya 《Journal of the American Ceramic Society》2020,103(9):5337-5353
Solid-state phase equilibria in the MgO-Y2O3-ZrO2 system as well as the equilibria including liquid were investigated in the whole-compositional range using high-temperature differential thermal analysis (DTA), X-ray diffraction (XRD), and scanning electron microscopy combined with energy dispersive X-ray spectroscopy (SEM/EDX). Isothermal sections at 1493, 1573, 1693, and 1923 K were constructed based on experimental studies. The presence of tie line between MgO and Y4Zr3O12 in the temperature range between 1493 and 1573 K was confirmed. The eutectic melting in the MgO-Y2O3-ZrO2 system was established using DTA followed by SEM/EDX microstructure investigation. Based on the obtained experimental results, the thermodynamic database was derived. 相似文献
453.
Influence of the feed pipe position of an industrial scale two‐phase decanter on extraction efficiency and chemical‐sensory characteristics of virgin olive oil 下载免费PDF全文
454.
Andrea Pucci Filippo Donati Samuele Nazzi Gloria Uccello Barretta Gennaro Pescitelli Lorenzo Di Bari Giacomo Ruggeri 《Reactive and Functional Polymers》2010,70(12):951-960
In this work, the aggregation behaviour of a chiral perylene derivative, that is, N,N′-bis-(R)-(1′-phenylethyl)-perylene-3,4,9,10-tetracarboxyldiimide (R-Pery), was studied by means of 1H NMR (including DOSY techniques), circular dichroism, UV–Vis and fluorescence spectroscopies in various conditions. The acquired data demonstrate that R-Pery tends to aggregate in pure solvents at high concentrations (>10?5 M in DMSO and >10?3 M in CHCl3), whereas aggregation occurred at lower concentrations by adding a poor solvent, such as water (to DMSO) or CH3CN (to chloroform). Interesting results were obtained studying the optical behaviour of R-Pery when dispersed into a linear low-density polyethylene matrix (LLDPE). In particular, the aggregation extent of R-Pery into LLDPE was investigated by means of UV–Vis, fluorescence and CD spectroscopies as a function of dye concentration as well as thermal stimuli. The optical responsiveness of R-Pery (both in absorption and in emission) versus moderate temperature changes (i.e., for T > 35 °C) suggests applications of polymer dispersions as smart and reversible indicators to thermal solicitations. 相似文献
455.
Giacomo Lazzarino Romina Pallisco Gabriele Bilotta Ilaria Listorti Renata Mangione Miriam Wissam Saab Giuseppe Caruso Angela Maria Amorini Maria Violetta Brundo Giuseppe Lazzarino Barbara Tavazzi Pasquale Bilotta 《International journal of molecular sciences》2021,22(16)
Nearly 40–50% of infertility problems are estimated to be of female origin. Previous studies dedicated to the analysis of metabolites in follicular fluid (FF) produced contrasting results, although some valuable indexes capable to discriminate control groups (CTRL) from infertile females (IF) and correlate with outcome measures of assisted reproduction techniques were in some instances found. In this study, we analyzed in blind FF of 35 control subjects (CTRL = patients in which inability to obtain pregnancy was exclusively due to a male factor) and 145 IF (affected by: endometriosis, n = 19; polycystic ovary syndrome, n = 14; age-related reduced ovarian reserve, n = 58; reduced ovarian reserve, n = 29; unexplained infertility, n = 14; genetic infertility, n = 11) to determine concentrations of 55 water- and fat-soluble low molecular weight compounds (antioxidants, oxidative/nitrosative stress-related compounds, purines, pyrimidines, energy-related metabolites, and amino acids). Results evidenced that 27/55 of them had significantly different values in IF with respect to those measured in CTRL. The metabolic pattern of these potential biomarkers of infertility was cumulated (in both CTRL and IF) into a Biomarker Score index (incorporating the metabolic anomalies of FF), that fully discriminated CTRL (mean Biomarker Score value = 4.00 ± 2.30) from IF (mean Biomarker Score value = 14.88 ± 3.09, p < 0.001). The Biomarker Score values were significantly higher than those of CTRL in each of the six subgroups of IF. Posterior probability curves and ROC curve indicated that values of the Biomarker Score clustered CTRL and IF into two distinct groups, based on the individual FF metabolic profile. Furthermore, Biomarker Score values correlated with outcome measures of ovarian stimulation, in vitro fertilization, number and quality of blastocysts, clinical pregnancy, and healthy offspring. These results strongly suggest that the biochemical quality of FF deeply influences not only the effectiveness of IVF procedures but also the following embryonic development up to healthy newborns. The targeted metabolomic analysis of FF (using empowered Redox Energy Test) and the subsequent calculation of the Biomarker Score evidenced a set of 27 low molecular weight infertility biomarkers potentially useful in the laboratory managing of female infertility and to predict the success of assisted reproduction techniques. 相似文献
456.
Thermal comfort and energy saving are objectives of key significance that building design must meet. Since a low energy building
can be obtained as a result of the good realization of all its components, roofs call for particular attention as they represent
a large part of a building’s total surface area. In this paper the benefit of using ventilated roofs for reducing summer cooling
load is investigated. The investigation has been conducted comparing a ventilated roof assembly with different channel heights
(3 cm, 5 cm, and 10 cm) to the same non ventilated structure, assuming buoyancy-driven airflow. Direct comparison between
the open and the closed roof structures as a function of different cavity heights and outside environmental conditions is
presented. To provide fundamental information about the thermal performance of these building envelope components, the computational
fluid dynamics (CFD) model has been used to develop correlations for the characterization of the airflow and heat transfer
phenomena in the ventilation cavity which have been implemented in a whole year energy simulation software. The present analysis
shows a conflicting discrepancy among the indexes of performance describing the actual energy saving potential of a ventilated
roof. 相似文献
457.
Spatiotemporal receptive fields of cells in V1 are optimally shaped for stimulus velocity estimation
Cocci G Barbieri D Sarti A 《Journal of the Optical Society of America. A, Optics, image science, and vision》2012,29(1):130-138
In recent literature, particularly interesting stimulus velocity-selective behaviors were found in the response properties of neurons belonging to the primary visual cortex (V1). In this work, 93 simple and complex cell receptive fields were obtained from the recordings of different experiments made on cats (DeAngelis, Blanche, Touryan) with reverse correlation and the spike-triggered covariance methods and then fitted with a three-dimensional Gabor model, so that cells are seen as minimizers of the Heisenberg uncertainty principle over both space and time. Analysis of the model parameters' cortical distribution suggests that V1 is spatiotemporally organized to maximize the resolution on the stimulus velocity measure. 相似文献
458.
Giacomo Po Mamdouh S. Mohamed Tamer Crosby Can Erel Anter El-Azab Nasr Ghoniem 《JOM Journal of the Minerals, Metals and Materials Society》2014,66(10):2108-2120
We present a self-contained review of the discrete dislocation dynamics (DDD) method for the numerical investigation of plasticity in crystals, focusing on recent development and implementation progress. The review covers the theoretical foundations of DDD within the framework of incompatible elasticity, its numerical implementation via the nodal method, the extension of the method to finite domains and several implementation details. Applications of the method to current topics in micro-plasticity are presented, including the size effects in nano-indentation, the evolution of the dislocation microstructure in persistent slip bands, and the phenomenon of dislocation avalanches in micro-pillar compression. 相似文献
459.
460.
Samuela Cataldi Michela Codini Giacomo Cascianelli Sabina Tringali Anna Rita Tringali Andrea Lazzarini Alessandro Floridi Elisa Bartoccini Mercedes Garcia-Gil Remo Lazzarini Francesco Saverio Ambesi-Impiombato Francesco Curcio Tommaso Beccari Elisabetta Albi 《International journal of molecular sciences》2014,15(11):19832-19846