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41.
Near-infrared reflectance (NIR) spectra was recorded of 105 samples of cod mince prepared from chill stored thawed cod fillets of varying quality in modified atmosphere packaging (MAP). Traditional chemical, physical, microbiological and sensory quality methods developed for assessing fresh fish products were determined on the same cod fillets. The purpose was to evaluate the potential of NIR spectroscopy for estimating (i) frozen storage temperature, (ii) frozen storage period and (iii) chill storage period of thawed-chilled MAP Barents Sea cod fillets. Furthermore, the potential for measuring of selected quality attributes as drip loss, water holding capacity and content of dimethylamine by NIR was evaluated. The results of the investigation were presented using multivariate modelling methods such as partial least-squares regression (PLSR) and discriminant partial least-squares regression (DPLSR). Systematic differences in the NIR measurements on minced cod fillets were primarily due to the chill storage duration (days at 2°C) on thawed-chilled MAP fillets. PLSR models based on wavelengths selected by a new Jack-knife method resulted in a correlation coefficient of 0.90 between measured and predicted duration of chill storage period (days at 2°C). The root-mean-square error of cross-validation (RMSECV) was 3.4 d at 2°C. NIR measurements provided promising results for evaluation of freshness for thawed-chilled MAP cod fillets completing the traditionally quality methods. However, it is necessary to study the effect of e.g. sample preparation, season, fishing ground and cod size together with more sophisticated pre-treatments of NIR spectra before the NIR method can be integrated as a method for evaluation of thawed-chilled MAP cod fillets. 相似文献
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Validating smoking data from the Veteran's Affairs Health Factors dataset, an electronic data source
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Hangover Frequency and Risk for Alcohol Use Disorders: Evidence From a Longitudinal High-Risk Study.
Piasecki Thomas M.; Sher Kenneth J.; Slutske Wendy S.; Jackson Kristina M. 《Canadian Metallurgical Quarterly》2005,114(2):223
Data from a prospective high-risk study (N=489; 51% with a family history of alcoholism) were used to test whether family history is associated with greater hangover proneness and whether hangover is a risk factor for alcohol use disorders. Hangover was more frequent in family-history-positive participants during the college years. Persons with an alcohol diagnosis showed excess hangover before earning a diagnosis. Year 1 hangover predicted alcohol use disorders at Years 7 and 11, even when family history, sex, Year 1 diagnoses, and Year 1 drinking were statistically controlled. Several nonhangover drinking symptoms failed to predict later diagnoses. Taken together, the findings suggest a need for further research and theory on the role of hangover in the etiology of drinking problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Molecular‐Scale Hybridization of Clay Monolayers and Conducting Polymer for Thin‐Film Supercapacitors 下载免费PDF全文
Jingwen Zhao Simin Xu Kristina Tschulik Richard G. Compton Min Wei Dermot O'Hare David G. Evans Xue Duan 《Advanced functional materials》2015,25(18):2745-2753
Development of electrode materials with well‐defined architectures is a fruitful and profitable approach for achieving highly‐efficient energy storage systems. A molecular‐scale hybrid system is presented based on the self‐assembly of CoNi‐layered double hydroxide (CoNi‐LDH) monolayers and the conducting polymer (poly(3,4‐ethylene dioxythiophene):poly(styrene sulfonate), denoted as PEDOT:PSS) into an alternating‐layer superlattice. Owing to the homogeneous interface and intimate interaction, the resulting CoNi‐LDH/PEDOT:PSS hybrid materials possess a simultaneous enhancement in ion and charge‐carrier transport and exhibit improved capacitive properties with a high specific capacitance (960 F g–1 at 2 A g–1) and excellent rate capability (83.7% retention at 30 A g–1). In addition, an in‐plane supercapacitor device with an interdigital design is fabricated based on a CoNi‐LDH/PEDOT:PSS thin film, delivering a significantly enhanced energy and power output (an energy density of 46.1 Wh kg–1 at 11.9 kW kg–1). Its application in miniaturized devices is further demonstrated by successfully driving a photodetector. These characteristics demonstrate that the molecular‐scale assembly of LDH monolayers and the conducting polymer is promising for energy storage and conversion applications in miniaturized electronics. 相似文献
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The proposed Stochastic Energy Source Access Management (SESAM) comprises renewable energy sources coupled via a direct current bus with storage modules of complementary characteristics to achieve co-generation of hydrogen and electric power on a continuous duty basis. As complementary solutions, hydrogen energy storage to provide a large capacity and access-oriented storage based on magnetic, electric or kinetic energy with less capacity but a faster response time are considered. These are arranged to form a multi-level storage that can compensate stochastic fluctuations of power over diverse time scales. The developed energy management coordinates the operation of the diverse storage modules. In this context, the access-oriented storage acts as a shock absorber in order to shield fuel cells and electrolysers from fast fluctuations of wind power and load. The functions of the plant are validated through simulation using meteorological information obtained from the National Wind Technology Center in the USA. The plant is shown to provide the scheduled output of hydrogen and electric power. Since seen from its terminals SESAM behaves in the same way as a power plant with controlled fuel input, it can be readily integrated with given infrastructures. 相似文献
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Kristina Georgoulakis George-Othon Glentis 《Signal processing》2011,91(11):2671-2676
In this paper an efficient decision feedback equalizer is presented for the equalization of the received signal in the eight level vestigial sideband, Advanced Television Systems Committee, digital television system, adopting a novel detection rule for symbol detection at the output of the equalizer. The conventional hard limiter is replaced by an efficient symbol detection algorithm, based on the underlying trellis coded modulated coding of the transmitted symbols. The proposed decision device has a marginal computational cost and it can be implemented using simple combinatorial and sequential logic circuitry. When the equalizer operates in the decision directed mode, the normalized least mean squared algorithm is utilized for the adaptation of the equalizer coefficients, in a “stop-and-go” like mode, triggered by a reliability signal associated to the detected symbols. The performance of the proposed method is illustrated by typical computer simulation. 相似文献
50.
Tschulik K Cierpka C Gebert A Schultz L Kähler CJ Uhlemann M 《Analytical chemistry》2011,83(9):3275-3281
A novel three-dimensional particle tracking velocimetry technique was used to examine the flow during electrodeposition of Cu. For the first time electrode-normal, circumferential, and radial velocities were spatially resolved during deposition in superimposed low and high magnetic gradient fields. In this way the complex interaction of magnetic field gradient force and Lorentz force induced convective effects could be measured and analyzed. Magnetic field gradient force induced electrolyte flow was detected only in high gradient magnetic fields, and it was found to be directed toward regions of gradient maxima. Since this electrode-normal flow causes enhanced transport of Cu(2+) ions from the bulk electrolyte to those regions of the working electrode where maxima of magnetic gradients are present, a structured deposit is formed during diffusion-limited electrodeposition. Lorentz force driven convection was observed during deposition in the low and the high magnetic gradient experiments. The overall fluid motion and the convection near the working electrode were determined experimentally and discussed with regard to the acting magnetic forces and numerical simulations. 相似文献