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101.
A Monte Carlo code called CARLO DTS, developed for the efficiency and proton recoil spectra calculation of the Dual Thin Scintillator (DTS) neutron detector is described. The code CARLO DTS covers the neutron energy range between 1 and 20 MeV. The cross sections and angular distributions were taken from the ENDF/B-V data file for the nuclear reactions involved: H(n.n)H, C(n,n)C and inelastic scattering, (n,), (n,n′)3 reactions on carbon-12. The theoretical calculations are compared to experimental results at two neutron energies, namely:2.446 and 14.04 MeV, obtained by means of the Time Correlated Associated Particle Technique.  相似文献   
102.
Modeling of critical dimensions scanning electron microscopy with sub-nanometer uncertainty is required to provide a metrics and to avoid yield loss in the processing of advanced CMOS technologies. In this paper, a new approach is proposed, which includes a new Monte Carlo scheme, a new Monte Carlo code, as well as the coupling with electrostatic fields to take into account self-charging effects.  相似文献   
103.
We briefly review some simple lattice models, introduced recently to study granular systems based on the similarities with glassy systems. The basic common ingredient, partially responsible for the complex behavior shown, is geometric frustration due to steric hindrance. Received: 30 March 2000  相似文献   
104.
In this work we compare the performance of Scanning Capacitance Microscopy and Scanning Spreading Resistance Microscopy for the characterization of doping profiles in semiconductor devices. Particular attention is devoted to parameters of paramount importance for the failure analysis and the characterization of silicon devices, like the quantitative one-dimensional profiling accuracy, the electrical junction delineation and the two-dimensional sub-micron imaging capability.  相似文献   
105.
106.
In this work we present results about the deuterium isotope effect on the global kinetics of a Belousov-Zhabotinsky reaction in batch conditions. A nonlinear dependence of the Induction Period upon the percentage of deuterated reactants was found. The isotopic effect on the bromination reaction of malonic acid was evaluated.  相似文献   
107.
The field of glass science is at a critical juncture. With many recent advances in theoretical glass physics, computational capabilities, and processing and characterization technology, there has surely never been a more exciting time to be a glass scientist. However, much of our current glass science education focuses on concepts that have been rejected based on a combination of rigorous theory and experimental observations. In this article, I review three common misconceptions often taught in glass science curricula, viz., the Kauzmann paradox, the divergence of supercooled liquid dynamics, and the notion of residual entropy. In each case, there is now ample experimental and theoretical evidence disproving these concepts. These topics are misleading and confusing to students in the field, and I argue that a better use of the students’ time would be to focus on building a rigorous foundation in the underlying physics, chemistry, and mathematics of glass. Such a rigorous foundation is necessary for students to be successful in the high-technology jobs of the future and to discover the next great advances in glass science and technology.  相似文献   
108.
Sigma‐2 (σ2) binding sites are an emerging target for anti‐neoplastic agents due to the strong apoptotic effect exhibited by σ2 agonists in vitro and the overexpression of these sites in tumor cells. Nonetheless, no σ2 receptor protein has been identified. Affinity chromatography using the high‐affinity σ2 ligand PB28 and human SK‐N‐SH neuroblastoma cells was previously utilized to identify σ2 ligand binding proteins, specifically histones H1, H2A, H2B, and H3.3a. To rationalize this finding, homology modeling and automated docking studies were employed to probe intermolecular interactions between PB28 and human nucleosomal proteins. These studies predicted interaction of PB28 with the H2A/H2B dimer at a series of sites previously found to be implicated in chromatin compaction and nucleosomal assembly. To experimentally verify this prediction, a competitive binding assay was performed on the reconstituted H2A/H2B dimer using [3H]PB28 as radioligand, and an IC50 value of 0.50 nM was determined for PB28 binding. In addition, [3H]PB28 was found to accumulate with up to a fivefold excess in nuclear fractions over cytosolic fractions of SK‐N‐SH and MCF7 cells, indicating that PB28 is capable of entering the nucleus to interact with histone proteins. In conjunction with computational results, these data suggest that PB28 may exert its cytotoxic effect through direct interaction with nuclear material.  相似文献   
109.
In this paper the author analyses the emergence of environmental education discourse from a Foucauldian perspective. The aim is to make evident the discursive play where environmental education became a possible practice. Then, the author tries to draw a discursive landscape through which environmental education appears as a knowledge and analyses the correlations between the knowledge techniques and power strategies invested in this discourse. At the end, the author points out the subjectivation ways produced by these knowledge-power relations and stresses some of the political and ethical problems involved in environmental education discourse.  相似文献   
110.
BACKGROUND: The present article reports the anthocyanin content in the berry skin and wine of the Italian red grape cultivar Aglianico (clone VCR11 grafted onto 1103 Paulsen), one of the most ancient vines and famous for its deep‐red colour. Anthocyanins were extracted from frozen berry skin in an acidified methanol solution. The extraction mixtures, monitored for 120 h, were analysed by high‐performance liquid chromatography. RESULTS: The extraction from berry skin of delphinidin, petunidin and malvidin appeared to be a time‐independent process, whereas the concentration of peonidin increased linearly with time. Peonidin‐O‐acetyl‐glucoside was transferred from skin more slowly than petunidin‐O‐acetyl‐glucoside and malvidin‐O‐acetyl‐glucoside. The anthocyanin composition of the resulting wine showed that the total anthocyanin content was about one‐tenth of the corresponding berry skin content. The ratio acetyl/coumaroyl anthocyanins in the wine was sharply higher than the value in berry skin (0.85 and 0.10, respectively), indicating an enrichment of acetyl derivatives in the wine. CONCLUSION: Levels of single anthocyanins in wine were not always correlated with those detected in grapes, as they were affected by winemaking. The high values of some anthocyanins in Aglianico wine could ameliorate its quality, increasing the chromatic properties, aging stability and product acceptance. Copyright © 2011 Society of Chemical Industry  相似文献   
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