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1.
This paper describes how various characterisation methods can be used to investigate the physicochemical and spectral properties of gold films in contact with glass or ceramic. The interface between the metal and substrate has been given special attention. The examples chosen to illustrate this include: liquid gold films (decorated and fired) or inlayed gold layers on ceramic wares and “sandwich” gold foils between two glass sheets for mosaic application. Characterisation methods include: microanalytical scanning electron microscopy, X-ray diffraction, ion beam analyses (PIXE: particle induced X-ray emission; RBS: Rutherford back-scattering spectrometry), photo-spectrometry and colorimetry. The adhesion mechanism and colour behaviour of the coated objects is discussed.  相似文献   
2.
This study determines the influences of siloxane flow agents’ migration on the outermost surface composition of clearcoats, before and after ethanol cleaning. This evaluation is undertaken to improve adhesion of pressure-sensitive adhesives (PSAs) on automotive paint systems. Most of the siloxane flow agents segregate from the bulk to the clearcoat outermost surface during curing. These additives can cover until 50% of the surface area but X-ray photoelectron spectroscopy (XPS) and time of flight-secondary ion mass spectrometry (ToF-SIMS) analyses indicate that they can be removed by ethanol cleaning. Composition of the cleaned clearcoats surfaces are similar as the composition of clearcoat formulated without siloxane additives: the polyester-(melamine)-polyurethane network is more detected than before cleaning. However, outermost surface analyses show that several aging weeks increase the siloxane additives segregation. This post-cleaning migration modifies the clearcoat surface composition and cancels the chemical modifications due to the ethanol cleaning. XPS analyses show that silicon concentrations after cleaning and aging are inversely proportional to the initial silicon concentrations measured after curing. It highlights that aging has to be controlled to improve adhesion of PSAs on clearcoats. A second ethanol cleaning on aged clearcoats is not effective to remove these new siloxane additives. Their formulation should be different from the flow agents and it could modify their solubility in ethanol. This result could also indicate that these new siloxane additives are not located on the last molecular layer of surface and they would not be soluble in ethanol.  相似文献   
3.
This article presents an adaptive approach to improving the infection algorithm that we have used to solve the dense stereo matching problem. The algorithm presented here incorporates two different epidemic automata along a single execution of the infection algorithm. The new algorithm attempts to provide a general behavior of guessing the best correspondence between a pair of images. Our aim is to provide a new strategy inspired by evolutionary computation, which combines the behaviors of both automata into a single correspondence problem. The new algorithm will decide which automata will be used based on the transmission of information and mutation, as well as the attributes, texture, and geometry, of the input images. This article gives details about how the rules used in the infection algorithm are coded. Finally, we show experiments with a real stereo pair, as well as with a standard test bed, to show how the infection algorithm works.  相似文献   
4.
Evelyne Fischer   《Calphad》2009,33(3):487-494
The ternary C–Pu–U system is thermodynamically assessed to pursue the development of a thermodynamic database for future nuclear fuels. The substitution model was used for the liquid phase, and a two-sublattice model for the PuC–UC monocarbide, PuC2–UC2 dicarbide and Pu2C3–U2C3 sesquicarbide phases. Ternary interaction parameters were adjusted on the experimental information for the phase relationships. Isoplethal and isothermal ternary sections, as well as some liquidus temperatures are calculated and compared with the experimental data. The overall agreement is discussed, and shows that experimental uncertainties still remain.  相似文献   
5.
6.
The aim of this human study was to assess the influence of prebiotic-induced gut microbiota modulation on PUFA-derived bacterial metabolites production. Therefore, we analyzed the circulating fatty acid profile including CLA/CLnA in obese women treated during 3 months with inulin-type fructan prebiotics. In these patients, we had already determined gut microbiota composition by phylogenetic microarray and qPCR analysis of 16S rDNA. Some PUFA-derived bacterial metabolites were detected in the serum of obese patients. Despite the prebiotic-induced modulation of gut microbiota, including changes in CLA/CLnA-producing bacteria, the treatment did not impact significantly on the circulating level of these metabolites. However, some PUFA-derived bacterial metabolites were positively correlated with specific fecal bacteria (Bifidobacterium spp., Eubacterium ventriosum and Lactobacillus spp.) and inversely correlated with serum cholesterol (total, LDL, HDL). These correlations suggest a potential beneficial effect of some of these metabolites but this remains to be confirmed by further investigation.  相似文献   
7.
Highly purified allergens namely cow's milk alpha-lactalbumin (ALA). (Bos d 4), beta-lactoglobulin (BLG) (Bos d 5) and casein (Bos d 8) and goat's milk casein were prepared from the raw milk from a single animal with a known genetic background. Consequently the natural isoforms are limited, constant and characterized. Purification included selective precipitations and chromatographical steps. Characterization of structure and allergenic activity assessment of milk allergens were carried out using physicochemical and immunochemical methods. Taken together data demonstrated the absence of impurities and of contamination by other milk allergens in each preparation. NMR and circular dichroism analyses confirmed the native conformation and proper folding of ALA and BLG and the expected absence of folding of bovine and caprine casein. Enzyme immuno assays confirmed the native conformation of BLG and the purity and immunoreactivity of all the proteins. The allergenic activity, e. g. the IgE binding capacity, of purified proteins was identical as that of those proteins when present in milk. The purified proteins also demonstrated the ability to provoke the degranulation of humanized rat basophilic leukaemia cells. All the data thus confirm the purity, identity, structural conformation and functionality of the prepared milk allergens.  相似文献   
8.
This study was undertaken to screen fatty acids, conjugated isomers of linoleic acid (CLA), and monolaurin for antilisterial effects in broth, and to further test the active compounds in cooked comminuted beef and hot dogs. Capric, lauric, myristic, palmitic, stearic, oleic, linoleic, and linolenic acid, CLA and monolaurin were screened in sterile nutrient broth at concentrations of 5 to 700 μg/ml. The media were inoculated with 103 cfu/ml of L. monocytogenes strain Scott A and incubated at 32°C for up to 8 days. Cell enumeration data showed that lauric acid was most inhibitory, followed by monolaurin, and capric acid. Tests in comminuted sterile beef stored at 5°C for 21 days showed log cfu/g of: 8.5 (control), 7.3 (500 μg/g lauric acid), and 4.7 (500 lauric acid+300 capric acid). Similar results were observed in beef hot dog emulsion to which lauricidin, lauric acid, capric acid, and the acid combination were added prior to heat treatment. At 500 μg/g, monolaurin and lauric acid caused similar delayed growth effects at 5°C, whereas the combination of the two acids showed enhanced inhibition on prolonged storage. Nonetheless, the observed 5-log increase in numbers of L. monocytogenes during 45 days of storage indicates limited control of the pathogen in refrigerated cooked meat products.  相似文献   
9.
In the dairy industry re-use and multi-use cleaning-in-place (CIP) systems are operated by circulating chemicals and water without taking the equipment apart. The solutions, which become polluted due to the removal of fouling compounds, are drained periodically when they are considered to be too polluted. This work shows the large variations in composition (pollution, surface tension, etc) of the industrial caustic solutions coming from milk standardization and pasteurization plant CIP throughout their life time (7 days) and from 1 week to another. The work is also intended to show how nanofiltration (1 kg mol(-1) molecular weight cut-off) was robust and performed well, with good recovery of caustic solutions, even when faced with large variations of solutions composition: high caustic yield, permeation flux (J) in the range 42-110 l h(-1) m(-2), average chemical oxygen demand (COD) reduction equal to 0.58 and low surface tension change. Equations have been established for the prediction of J as a function of initial membrane hydraulic resistance (Rm) caustic concentration, volume reduction ratio (VRR) and initial soluble COD. When VRR increased, both J and pollution retention decreased despite the increase in irreversible fouling induced by the increase of soluble pollution concentration in retentate. The higher the initial soluble COD, the sharper the decrease in J vs. VRR. Since irreversible fouling was usually small (0.1-3.4 x 10(13) m(-1), that is to say of the same order of magnitude as Rm), the membrane cleaning could be efficiently performed by using single phase sodium hypochlorite alternately with a more expensive acid-base cleaning sequence. The obtained permeate was a clear regenerated cleaning solution with low soluble COD (0.2-3.5 g/l) and surface tension (56-30 mJ m(-2)) which could be successfully exploited owing to its cleaning potential.  相似文献   
10.
Campylobacter spp. were recovered from 660 (77.6%) of 850 swine cecal contents at the abattoir and from 24 (8.6%) of 278 specimens from sporadic cases of human diarrhea during the same period in the same geographical area. Campylobacter coli represented 95.7% of Campylobacter isolates recovered from pigs and 8.3% of those isolated from humans. Genetic profiles were determined by pulsed-field gel electrophoresis (PFGE) using KpnI enzyme to characterize the isolates in combination with phenotypic assays to detect production of cytotoxins, enterotoxins, and hemolysins. Among a subset of isolates (n = 10), up to five colonies from the same animal were characterized by PFGE. In 5 (50%) of 10 of the isolates, more than one genetic profile was observed per pig. Among the 100 isolates from pigs selected for further analysis, 81 different genetic profiles were observed, whereas 20 different genetic profiles were found among the 24 isolates of human origin. Cytotoxicity on Chinese hamster ovary cells was observed in 11 (11%) of 98 isolates from pigs and in 5 (21%) of 24 Campylobacter isolates from humans. No enterotoxin production was detected in Campylobacter isolates in this study, but 17 (71%) of 24 human and 61 (63%) of 97 pig isolates showed hemolytic activity. The study of genotypic and phenotypic profiles of swine and human isolates revealed no epidemiological relationship between isolates. The low genomic relatedness observed between groups of isolates and the weak toxicity level of swine isolates suggest that the hazard of contamination of humans by Campylobacter associated with swine production is low.  相似文献   
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