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141.
Maria Pieralice Lucrezia Sergio Donato Di Venere Pavel Venediktov 《European Food Research and Technology》2011,232(5):919-923
The quality of leafy vegetables has to be guaranteed for consumers over the whole postharvest period, usually limited to 5–7 days.
The analyses to evaluate the quality of vegetables are very time- and resource consuming, so the use of qualitative markers
can be much useful. The aim of this work was to evaluate the use of thermoluminescence (TL) parameters as qualitative markers
of fresh-cut leafy vegetables during the shelf life. TL is a technique consisting of a cooling, followed by the progressive
warming, of a preilluminated sample to reveal the different types of charge pairs as successive emission bands, which are
resolved better than the corresponding decay phases recorded at constant temperature. Experiments were performed on rocket
(Diplotaxis tenuifolia L.) stored at 2 °C for 7 days. During storage, several changes in TL glow curves were found. The position of the peaks showed
a shift to higher temperature. The area of the peaks, relating to the photosystem II (20–65 °C), grew up lightly; whereas
in the temperature range that detects lipidic peroxidation (65–140 °C), the TL emission became more than twice. These changes
demonstrated that, during the shelf life, a progressive destabilization of PSII centres occurred and that lipid peroxidation
products were accumulated in membranes. TL could be used to estimate the damages immediately after as well as during the storage
period. This is the first time that TL was used to evaluate the quality of fresh-cut vegetables products during the shelf
life. 相似文献
142.
143.
Yonghong Huang Deniz Erdogmus Misha Pavel Santosh Mathan Kenneth E. Hild 《Neurocomputing》2011,74(12-13):2041-2051
We report the design and performance of a brain computer interface for single-trial detection of viewed images based on human dynamic brain response signatures in 32-channel electroencephalography (EEG) acquired during a rapid serial visual presentation. The system explores the feasibility of speeding up image analysis by tapping into split-second perceptual judgments of humans. We present an incremental learning system with less memory storage and computational cost for single-trial event-related potential (ERP) detection, which is trained using cross-session data. We demonstrate the efficacy of the method on the task of target image detection. We apply linear and nonlinear support vector machines (SVMs) and a linear logistic classifier (LLC) for single-trial ERP detection using data collected from image analysts and naive subjects. For our data the detection performance of the nonlinear SVM is better than the linear SVM and the LLC. We also show that our ERP-based target detection system is five-fold faster than the traditional image viewing paradigm. 相似文献
144.
We address the problem of credit scoring as a classification and feature subset selection problem. Based on the current framework of sophisticated feature selection methods, we identify features that contain the most relevant information to distinguish good loan payers from bad loan payers. The feature selection methods are validated on several real‐world datasets with different types of classifiers. We show the advantages following from using the subspace approach to classification. We discuss many practical issues related to the applicability of feature selection methods. We show and discuss some difficulties that used to be insufficiently emphasized in standard feature selection literature. © 2005 Wiley Periodicals, Inc. Int J Int Syst 20: 985–999, 2005. 相似文献
145.
Lubomír Kubáč Jiří Akrman Ladislav Burgert Drahomír Dvorský Pavel Grüner 《应用聚合物科学杂志》2009,112(6):3605-3612
New types of reactive UV absorbers for applications to cellulose textiles have been prepared. These substances are condensation products of sulfobenzimidazolaniline, cyanuric chloride, and aminophenyl‐(2‐sulfethoxy)‐sulfone. They were applied to bleached, unbleached, as well as dyed cellulose textiles with the aim to increase the protection effect of these textiles against UV radiation. All the tested textiles showed a marked increase in the UV protection factor (UPF). The effects of the UV absorbers tested neither interfere with the function of fluorescent brighteners (FBs) nor affect the hue of the used dyestuffs. They exhibit synergistic effect in the protection effectiveness against UV radiation: the UV absorbers used together with dyestuffs and FBs have a higher UPF factor than is the sum of UPF contributions of the individual components. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
146.
An uncommon electrolyte, based on sulphosalicylic acid, was used for nickel-cobalt deposition. Some mechanical properties (internal stress and microhardness) and structural properties of the deposits have been presented. High microhardness (nearly 800 HM) with simultaneous low internal stress (about 50 MPa) can be reached. 相似文献
147.
148.
Pavel Seredin Dmitry Goloshchapov Yuri Ippolitov Jitraporn Vongsvivut 《International journal of molecular sciences》2021,22(12)
The aim of this work is to develop a biomimetic interface between the natural tooth tissue and the restorative composite and to study it on the basis of synchrotron micro-FTIR mapping and multidimensional processing of the spectral data array. Using hierarchical cluster analysis of 3D FTIR data revealed marked improvements in the formation of the dentine/adhesive/dental hybrid interface using a biomimetic approach. The use of a biomimetic strategy (application of an amino acid–modified primer, alkaline calcium and a nano-c-HAp–modified adhesive) allowed the formation of a matrix that can be structurally integrated with natural dentine and dental composite. The biomimetic hybrid layer was characterised by homogeneous chemical composition and a higher degree of conversion of the adhesive during polymerisation, which should provide optimal integration of the dental composite with the dentine. 相似文献
149.
Yu. I. Koshurinov V. G. Pavel’ev M. I. Petelin I. V. Turchin D. Yu. Shchegol’kov 《Technical Physics Letters》2005,31(8):709-711
A diplexer with a resonance frequency of 34 GHz has been created based on a four-mirror ring resonator with two corrugated
mirrors. When the incident wave frequency varies by more than 20 MHz, the output wave beam is completely switched from one
direction to another. A diplexer of this type can be used for discrete frequency scanning of high-power wave beams in systems
for the suppression of the hydrodynamic instabilities of plasma in magnetic traps. Such diplexers can also be combined so
as to form a multiplexer, which can be used in long-range multichannel communication and radar systems with synthesized frequency
bands. 相似文献
150.
Pavel Kagan Anath Fischer Pinhas Z. Bar‐Yoseph 《International journal for numerical methods in engineering》2003,57(8):1145-1175
This article presents two new methods for adaptive refinement of a B‐spline finite element solution within an integrated mechanically based computer aided engineering system. The proposed techniques for adaptively refining a B‐spline finite element solution are a local variant of np‐refinement and a local variant of h‐refinement. The key component in the np‐refinement is the linear co‐ordinate transformation introduced into the refined element. The transformation is constructed in such a way that the transformed nodal configuration of the refined element is identical to the nodal configuration of the neighbour elements. Therefore, the assembly proceeds as with classic finite elements, while the solution approximation conforms exactly along the inter‐element boundaries. For the h‐refinement, this transformation is introduced into a construction that merges the super element from the finite element world with the hierarchical B‐spline representation from the computational geometry. In the scope of developing sculptured surfaces, the proposed approach supports C0 as well as the Hermite B‐spline C1 continuous shapes. For sculptured solids, C0 continuity only is considered in this article. The feasibility of the proposed methods in the scope of the geometric design is demonstrated by several examples of creating sculptured surfaces and volumetric solids. Numerical performance of the methods is demonstrated for a test case of the two‐dimensional Poisson equation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献