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71.
A. A. Gowen C. P. O’Donnell M. Taghizadeh E. Gaston A. O’Gorman P. J. Cullen J. M. Frias C. Esquerre G. Downey 《Sensing and Instrumentation for Food Quality and Safety》2008,2(3):133-143
In this study, the potential application of hyperspectral imaging (HSI) for quality prediction of white mushroom slices during
storage at 4 °C and 15 °C was investigated. Mushroom slice quality was measured in terms of moisture content, colour (CIE
Lightness, L* and yellowness, b*) and texture (hardness, H and chewiness, Ch). Hyperspectral images were obtained using a
pushbroom line-scanning HSI instrument, operating in the wavelength range of 400–1,000 nm with spectroscopic resolution of
5 nm. Multiple linear regression (MLR) and Principal Component Regression (PCR) models were developed to investigate the relationship
between reflectance and the various quality parameters measured. 20 optimal wavelengths for quality prediction were selected
after performing an exhaustive search for the best subsets of predictor variables on a calibration set of 84 samples. PCR
applied to the set of optimal wavelengths gave the best performance as compared to MLR and PCR on the entire wavelength range.
When applied to an independent validation set of samples, PCR models developed on the calibration set were capable of predicting
moisture content with RMSEP of 0.74% w.b. and R
2 of 0.75, L* with RMSEP of 0.47 and R
2 of 0.95, b* with RMSEP of 0.66 and R
2 of 0.75, H with RMSEP of 0.49 N and R
2 of 0.77 and Ch with RMSEP of 0.27 N and R
2 of 0.72. Virtual images showing the distribution of moisture content on the mushroom surface were generated from the estimated
PCR model. Results from this study could be used for the development of a non-destructive monitoring system for prediction
of sliced mushroom quality. 相似文献
72.
The Friction-Reducing, Antiwear and Antioxidation Properties of an Organo-Molybdenum Lube Additive without Sulfur and Phosphorus 总被引:2,自引:2,他引:2
The engine oil specifications of ILSAC GF - 4 ( implemented 2004 ) and GF - 5 ( expected 2010 ) have in common three important OEM needs: (1) improved fuel economy and its retention, (2) emissions system compatibility (related to phosphorus and sulfur content), and (3) improved oil robustness for extended oil life capability (e. g., reduced high temperature deposits and engine sludge, improved oxidative stability, and better valve train wear protec- tion). For emission systems compatibility, there is a trend towards lower phosphorus and sulfur content in engine oils while maintaining high anti - oxidation and anti - wear performances. In this paper, the friction - reducing, antiwear and antioxidant properties of a sulfurfree and phosphorusfree molybdate ester compound as lubricant additive are discussed. The investigation showed that the molybdate ester enables good frictionreducing ability of the lubricant, and maintains low friction coefficients even after period of severe oil oxidation, which indicates the potential for excellent fuel economy retention in passenger car vehicles. For other organomolybdenum additives, the investigation showed their frictionreducing ability decreased greatly after oxidation of the oil, although the performance appeared to be very good with the fresh oil before aging. In addition, the molybdate ester demonstrated a synergistic effect in anti - wear protection with zinc dialkyl dithiophosphate (ZDDP), a well- known commonly used additive in engine oils; this suggests that excellent wear protection is possible for an engine oil with reduced sulfur and phosphorus content. Moreover, the molybdate ester is also a strong synergist with arylamine antioxidants, which can retard its depletion in oxidized oil, extend its oxidative induction time, and reduce its high temperature deposit - forming tendency. Thus, this type of sulfur - free and phosphorus - free organo- molybdenum lubricant additive truly provides multifunctional performances, reducing friction, wear, and oxidation of an engine oil when combined with other suitable additives. Due to its phosphorus - free, sulfur- free and multifunctional properties, the molybdate ester compound can be extremely useful in formulat- ing modem engine oils with low phosphorus and sulfur content. 相似文献
73.
Willy Gaston Van Rillaer Hedwig Beernaert Willy Dejonckheere 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1988,187(2):97-101
Summary This study describes two methods for the quantitative determination of the residual fumigants ethylene dichloride (EDC), carbon tetrachloride (CCl4), trichlorethylene (TCE), ethylene dibromide (EDB) and tetrachlorethylene (PCE) in cereals (especially wheat) and other foodstuffs. In the first method, a micro steam distillation- solvent extraction apparatus is used, while the second method is based on a headspace technique. For the quantitative determination of carbon tetrachloride in cereals, the multiple headspace technique is not retained because it is too time-consuming. The analysis of the different fumigants is performed by electron-capture gas chromatography, using a fused silica capillary column, CP sil 8 CB. With the steam distillation-solvent extraction method, recoveries from 95.9% to 100.5% are obtained for the fumigants, added at two different levels. The standard deviation varies between 1.1 % and 6%. Using the simple headspace technique, recoveries from 73.5% to 85.1 % with a standard deviation of between 1.7% and 6.6% have been reached for the fumigants in cereals fortified at two different levels. The absulute detection limits for the five fumigants EDC, CCl4, TCE, EDB and PCE, in both methods, are 30, 0.25, 1.1, and 0.5 pg, respectively.
Bestimmung von Begasungsmitteln in Getreide und Getreideprodukten durch Capillar-Gaschromatographie
Zusammenfassung Es wurden zwei Methoden für die quantitative Bestimmung der Restmengen von Begasungsmitteln wie 1,2-Dichlorethan (EDC), Tetrachlorkohlenstoff (CCl4), Trichlorethylen (TCE), 1,2-Dibromethan (EDB) und Tetrachlorethylen (PCE) im Getreide, insbesondere Weizen, und in Lebensmitteln beschrieben. Das erste Verfahren basiert auf einer Mikrodampfdestillation-Lösungsmittelextraktion, während für das zweite die Kopfraumtechnik verwendet wurde. Da mehrfache Kopfraum-Extraktion bei der Bestimmung des Tetrachlorkohlenstoffes in Getreide zu zeitraubend ist, wurde diese Methode nicht beibehalten. Die Begasungsmittel wurden durch Elektroneneinfang-Gaschromatographie unter Verwendung einer CP sil. 8 CB silica Glaskolonne bestimmt. Mit der Dampfdestillation-Lösungsmittelextraktion wird eine Ausbeute von 95,9 bis 100,5% für fünf Begasungsrestmengen in zwei verschiedene Konzentrationen erreicht. Die Standardabweichung varriiert zwischen 1,1 und 6%. Die einfache Kopfraum-Extraktion gibt für zwei verschiedene Konzentrationen eine Ausbeute von 73,5 bis 85,1% mit einer Standardabweichung von 1,7 bis 6,6%. Die absolute Nachweisgrenze beider Methoden für die fünf Begasungsmittel EDC, CCl4, TCE, EDB und PCE ist 30, respektive 0,25, 1,1 und 0,5 pg.相似文献
74.
A square-root, linear quadratic optimal control algorithm is presented and realised on a new systolic array.<> 相似文献
75.
E Monlun A Leenhardt O Pillet R Gaston MC Receveur K Bouabdallah M Longy-Boursier JC Favarel-Garrigues M Le Bras 《Canadian Metallurgical Quarterly》1993,86(5):365-7; discussion 367-8
Incidence and malignant forms of imported Plasmodium falciparum malaria are increasing, and chemoprevention is more and more replaced by stand-by treatment and radical cure in preventing access on return from malaria areas. Halofantrine is recommended for this radical cure: it's an habitually well-tolerated amino-alcohol with very few side-effects. We report three cases of long QT-interval due to halofantine: three different young women coming back from Africa took halofantrine (500 mg (2 tablets) six hourly for three doses on the first and the seventh day) and all presented with syncopal episodes. Serum electrolyte concentrations and echocardiograms were normal. In one case only, a diagnosis of Plasmodium falciparum malaria was made, without severe manifestations, and in the two other cases, treatment was a radical cure. In two cases, several bursts of torsades de pointes ventricular tachycardia due to halofantrine were proven and electrophysiological cardiac tests concluded that they had a congenital long QT-interval/Romano-Ward syndrome). So far halofantrine cardiac toxicity was unknown with single dose of 24 mg/kg/d. This phenomenon can be very severe in case of preexisting cardiopathy. In spite of the rarity on the congenital Romano-Ward syndrome, systematic electrocardiogram is necessary before giving halofantrine. 相似文献
76.
Proposes the generalized least squares method, a time-series multiple-regression analysis, to simultaneously assess treatment efficacy and process correlates of outcome and to test alternative hypotheses of treatment efficacy. This approach can be applied to small samples by capitalizing on repeated measurements. Criteria for qualitative analysis are presented in an attempt to provide guidelines for the identification of significant therapeutic change events and the generation of hypotheses regarding factors involved in therapeutic change. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
77.
Koehler C Wischgoll T Dong H Gaston Z 《IEEE transactions on visualization and computer graphics》2011,17(12):2071-2079
We present the visual analysis of a biologically inspired CFD simulation of the deformable flapping wings of a dragonfly as it takes off and begins to maneuver, using vortex detection and integration-based flow lines. The additional seed placement and perceptual challenges introduced by having multiple dynamically deforming objects in the highly unsteady 3D flow domain are addressed. A brief overview of the high speed photogrammetry setup used to capture the dragonfly takeoff, parametric surfaces used for wing reconstruction, CFD solver and underlying flapping flight theory is presented to clarify the importance of several unsteady flight mechanisms, such as the leading edge vortex, that are captured visually. A novel interactive seed placement method is used to simplify the generation of seed curves that stay in the vicinity of relevant flow phenomena as they move with the flapping wings. This method allows a user to define and evaluate the quality of a seed's trajectory over time while working with a single time step. The seed curves are then used to place particles, streamlines and generalized streak lines. The novel concept of flowing seeds is also introduced in order to add visual context about the instantaneous vector fields surrounding smoothly animate streak lines. Tests show this method to be particularly effective at visually capturing vortices that move quickly or that exist for a very brief period of time. In addition, an automatic camera animation method is used to address occlusion issues caused when animating the immersed wing boundaries alongside many geometric flow lines. Each visualization method is presented at multiple time steps during the up-stroke and down-stroke to highlight the formation, attachment and shedding of the leading edge vortices in pairs of wings. Also, the visualizations show evidence of wake capture at stroke reversal which suggests the existence of previously unknown unsteady lift generation mechanisms that are unique to quad wing insects. 相似文献
78.
Harry H. Shorey Lyle K. Gaston Roland G. Gerber Phil A. Phillips David L. Wood 《Journal of chemical ecology》1992,18(11):2131-2142
Foraging in trees by the Argentine ant,Iridomyrmex humilis (Mayr), was disrupted by a variety of synthetic chemicals, with the most effective chemical being farnesol. Testing of substrates for presentation of the disruptant chemicals gave some success with rubber or Tygon tubing, although best results were obtained through incorporation of the material into Stikem, which was then banded around tree trunks. Amounts of farnesol used for effective, long residual ant control were between 0.8 and 2 g per tree. 相似文献
79.
In this work, the cure kinetics of a novel acrylated epoxidized hemp oil (AEHO)‐based bioresin was investigated for the first time by differential scanning calorimetry (DSC) using both isothermal and nonisothermal conditions. This new bioresin was synthesized by the acrylation of a previously epoxidized hemp oil (EHO) bioresin. The curing of the AEHO bioresin showed an autocatalytic behavior with the vitrification phenomenon preventing the conversion reaching unity for all the temperatures studied. It was found that the curing behavior can be modeled with high accuracy using a modified Kamal autocatalytic model that takes into account the vitrification phenomenon. Dynamic activation energies were determined from the Kissinger and Ozawa–Flynn–Wall methods, resulting in 58.87 and 62.02 kJmol?1, respectively. In addition, activation energies associated with the autocatalytic model constants, k1 and k2, were established to be equal to 58.94 and 45.32 kJmol?1, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
80.
The concept of the alliance and its role in psychotherapy: Theoretical and empirical considerations.
Reviews definitions of the alliance (ALI) concept and proposes 4 relatively independent ALI dimensions that are complementary and compatible. These include (1) the therapeutic ALI, (2) the working ALI, (3) the therapist's empathic understanding and involvement, and (4) the patient–therapist agreement on the goals and tasks of treatment. There is evidence to support the predictive validity of the ALI in psychotherapy, with observations available across a variety of psychotherapy approaches, symptomatic disorders in outpatient samples, and sources of information (patient, therapist, clinical judges). A lack of association between ALI and outcome was, however, observed in some studies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献