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111.
Agnar Holten Sivertsen Karsten Heia Kristian Hindberg Fred Godtliebsen 《Journal of food engineering》2012
Detection of objects embedded in tissue, using visible light, is difficult due to light scattering. The optical properties of the surrounding tissue will influence the spectral characteristics of the light interacting with the object, and the spectral signature observed from the object will be directly affected. A method for calibrating the spectral signature of small objects, embedded in translucent material, by the estimated local background spectrum is presented. The method is evaluated under industrial conditions in a new hyperspectral imaging system for automatic detection of nematodes in cod fillets. The system operates at a conveyor belt speed of 400 mm/s which meets the industrial required speed of assessing one fillet per second. The local calibration method reduces the number of spectra needed to be classified by 89.6%. For one or more false alarms in 60% of the fillets sampled after the trimming station, the Gaussian maximum likelihood classifier detects 70.8% and 60.3% of the dark and pale nematodes, respectively. This is better than what is previously reported using a higher resolution instrument on a slow moving conveyor belt, and comparable or better to what is reported for manual inspection under industrial conditions. 相似文献
112.
113.
Pd@Al2O3‐Catalyzed Hydrogenation of Allylbenzene to Propylbenzene in Methanol and Aqueous Micellar Solutions
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Oscar Arbelaez Luis Correa Riny Yolanda Parapat Kristian Knemeyer Felipe Bustamante Aída Luz Villa Michael Schwarze 《化学工程与技术》2015,38(12):2291-2298
The palladium on alumina (Pd@Al2O3)‐catalyzed hydrogenation of allylbenzene to propylbenzene was studied in methanol and aqueous micellar solutions of sodium dodecyl sulfate (SDS), decyltrimethylammonium bromide (DTAB), and t‐octylphenoxypolyethoxyethanol (TX‐100). Over Pd@Al2O3, propylbenzene was obtained via direct hydrogenation of allylbenzene and isomerization to β‐methylstyrene which was hydrogenated afterwards. In aqueous micellar solutions, the reaction was faster than in pure water, but slower than in methanol due to lower hydrogen solubility. In the H2O/SDS system, a higher activation energy was obtained than in methanol. For the investigated surfactants, the initial reaction rate in the micellar systems decreased in the order SDS > TX‐100 > DTAB. 相似文献
114.
The problem of granular column collapse is investigated by means of an axisymmetric version of the particle finite element method (PFEM). The granular medium is represented by a simple rate-independent plasticity model and the frictional contact between the granular flow and its rigid basal surface is accounted for. In the version of the PFEM developed for this study, the governing equations of the boundary value problem are cast in terms of an optimization problem and solved using mathematical programming tools. The agreement between model and experiment is generally satisfactory, quantitatively as well as qualitatively. However, the friction angle of the granular material, as well as the exact interface conditions between the base and granular material, are shown to have a relatively significant influence on the results. 相似文献
115.
Synthesis of Nano‐ and Micro‐Scale Topographies by Combining Colloidal Lithography and Glancing Angle Deposition (GLAD)
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116.
A multi-source forest inventory (MSFI) method has been developed for use in the Norwegian National Forest Inventory (NFI). The method is based on a k-nearest neighbour rule and uses field plots from the NFI, land cover maps, and satellite image data from Landsat Thematic Mapper. The inventory method is used to produce maps of selected forest variables and to estimate the selected forest variables for large areas such as municipalities. In this study, focus has been on the qualitative variables ‘dominating species group’ and ‘development class’ because these variables are of central interest to forest managers. A mid-summer Landsat 5 TM scene was used as image data, and all NFI plots inside the scene were used as a reference dataset. The relationship between the spectral bands and the forest variables was analysed, and it was found that the levels of association were low. A leave-one-out method based on the reference dataset was used to estimate the pixel-level accuracies. They were found to be relatively low with 63% agreement for species groups. An independent control survey was available for a municipality and estimates from the MSFI were compared to it. The levels of error were quite high. It was concluded that the large area estimates were biased by the reference dataset. 相似文献
117.
Steen B. Schougaard Niels Reitzel Kristian Kjaer Torben R. Jensen Ramon Colorado Jr. J.-H. Choi David Derro John T. McDevitt 《Thin solid films》2007,515(23):8424-8429
A self-assembled monolayer of CF3(CF2)3(CH2)11NH2 atop the (001) surface of the high-temperature superconductor YBa2Cu3O7-x was imaged by atomic force microscopy (AFM). The AFM images provide direct 2D-structural evidence for the epitaxial 5.5 Å square √2 × √2R45° unit cell previously predicted for alkyl amines by molecular modeling [J.E. Ritchie, C.A. Wells, J.-P. Zhou, J. Zhao, J.T. McDevitt, C.R. Ankrum, L. Jean, D.R. Kanis, J. Am. Chem. Soc. 120 (1998) 2733]. Additionally, the 3D structure of an analogous Langmuir monolayer of CF3(CF2)9(CH2)11NH2 on water was studied by grazing-incidence X-ray diffraction and specular X-ray reflectivity. Structural differences and similarities between the water-supported and superconductor-localized monolayers are discussed. 相似文献
118.
Jingwen Cui Margareta Sandahl Ola F. Wendt Irene Rodriguez-Meizoso 《Journal of surfactants and detergents》2019,22(6):1505-1514
This work explores the use of water-in-supercritical carbon dioxide (scCO2) microemulsions for the extraction of polar metabolites from plants. Stevia rebaudiana Bertoni leaves and polyethylene glycol trimethylnonyl ether (TMN) surfactants were selected for a case study. A CO2-water-TMN 10 mixture at 35 °C and 30.0 MPa extracted 7 mg target analyte/g dry leaves. The extraction was proven to occur due to a water-surfactant liquid solution rather than a water-in-CO2 microemulsion. Using a modified extraction setup, the microemulsion was created prior to extraction. TMN 6 was able to dissolve enough water in CO2 to extract steviol glycosides, in detectable but very small amounts. 相似文献
119.
Kathrin Sundberg Kristian Dreij Bengt Jernström Albrecht Seidel 《Polycyclic Aromatic Compounds》2013,33(3-4):947-953
V79MZ cells expressing human glutathione transferases (hGST) have been constructed and used to study glutathione (GSH) conjugation of anti -diol epoxides (DEs) of dibenzo[ a,l ]pyrene ( DBPDE ), and benzo[ a ]pyrene ( BPDE ). Cells expressing hGSTM1-1 were more effective with ( m )- anti - DBPDE than hGSTP1-1. The opposite was observed with (+)- anti - BPDE . Rates of cellular DE uptake and solvolysis in conjunction with oil/water partition coefficients were used to calculate the amount of DEs available for GST-catalyzed conjugation in the cells. Using this information and the known values of k cat /K M for (+)- anti - BPDE and ( m )- anti - DBPDE with purified hGSTs, it was calculated that up to 3% of available (+)- anti - BPDE forms GSH conjugates whereas the corresponding figure with the less reactive and more lipophilic ( m )- anti - DBPDE was about 19%. In part, the lower fraction of (+)- anti -BPDE conjugated in cells is probably due to rapid and competing reactions with cellular constituents. 相似文献
120.
The energy policy in Europe regarding buildings and the energy efficiency sector are regulated by two directives: 2002/91/CE - EPBD and 2006/32/CE - EEESD
[1] and [2].The CEN has elaborated a standard to revise all European normatives about building energy performance and HVAC plants. The “CEN Umbrella” CEN/TR 15615 [3] includes a new version of EN ISO 13790:2008 [4] and a new standard about heating plant, use and contributions of renewable energy sources. Furthermore, the CEN Standard provides a software version for technicians.In this paper we present a Round Robin Test between a selection of softwares applied to an Italian case study. The selected calculation methodologies, range from research packages to extra-simplified software. Furthermore, the Italian procedure described in UNI TS 11300 [5] has been analyzed and considered as the reference for all other calculation methodologies.The results of the Round Robin Test show the relationship between thoroughness of data input and energy evaluation accurancy. The more the input data is affected by uncertainty, the less precise is the energy efficiency calculation. On the other hand the energy performance of building evaluation accurancy depends on the aim of the simulation: the energy audit, the energy design or the energy labeling (certification). 相似文献