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101.
The human visual system has an exceptional ability to detect systematic print mottle. One type of systematic print mottle is banding on printed corrugated board, resulting in a disturbing print defect. A new method that quantifies banding on printed corrugated board is proposed. The method is based on spatial frequency analysis, and the degree of banding is determined using a band‐pass filter range adapted to fit the flute wavelength and orientation of the acquired image of the printed board. The results for B‐flute corrugated board gave a correlation coefficient of 0.98 between the technical measurements and the subjective ratings. Methods of quantifying the banding on the different types of corrugated board available on the market are discussed. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
102.
103.
The critical resolved shear stress (CRSS), τ 0, of peak-aged single crystals of the γ′-hardened commercial nickel-base superalloy NIMONIC 105 has been measured as a function of temperature T and orientation [hkl] of the compression axis. The same measurements have been carried out for the two constituent phases of NIMONIC 105: for the single-phase γ matrix and for the single-phase L12-long-range ordered γ′ phase. The value of T ranged from 283 to 1150 K, and the following orientations were studied: [001], [011], , and . The specimens were compression tested. The τ 0 values of NIMONIC 105 and of the γ′ phase are anisotropic; the anisotropy of NIMONIC 105 is similar to that of the γ′ phase, but less pronounced. The τ 0 of the γ phase is isotropic. The τ 0 values of the γ and of the γ′ phase vary with T, whereas the τ 0 of NIMONIC 105 is nearly independent of T for 400 K≤T≤1000 K. A model is presented that relates the function τ 0 ([h, k, l], T) of NIMONIC 105 to the analogous functions of its constituent γ and γ′ phase.  相似文献   
104.
The selection of a suitable sludge which will be the inoculum of the reactor is the first step in the start‐up procedure of an anaerobic reactor. The sludge selected (inoculum) for this study was obtained from a UASB (Up‐flow Anaerobic Sludge Bed) reactor used for the treatment of alcohol industry wastewaters. The industrial sludge was used in this work as the inoculum of two laboratory‐scale UASB anaerobic reactors, which were fed with different substrata. The feed for the first reactor was acidified substratum (volatile fatty acid) and the second reactor was fed with non‐acidified substratum (glucose). The purpose of this work was to study the effect of both substrata in regular operation and to analyse the flotation problem which arises when the reactor is fed with a non‐acidified substratum. Finally, the characteristics of the adapted sludge were studied and they were compared with the initial inolucum (sludge). The following observations were noted in relation to the evolution of the sludge during operation: density, TSS content and C, H and N contents remained similar, but the particle size and VSS/TSS increased. The settling volume index decreased and methanogenic and acidogenic activities increased during operation in both reactors. The reactor fed with volatile fatty acids was able to recover from unstable periods faster than the reactor fed with a non‐acidified substratum. The use of an acidified substratum avoided flotation, stabilised the system and reduced the solid content in the effluent. Moreover, it worked properly with partially acidified influents meaning a reduction in the chemical reactive expense required to control acid pH‐value throughout operation. © 1999 Society of Chemical Industry  相似文献   
105.
On the Reaction of Dicyclopentadiene Diepoxide with Acrylic Acid The esterification of dicyclopentadiene diepoxide as a bifunctional epoxide with acrylic acid was investigated. The influence of solvent polarity, reaction temperature and the catalytic system used are discussed. It was found, that the reaction rate increased with increasing solvent polarity. By using tertiary amines as catalysts, only a small catalytic effect was observed. On the contrary, a good catalytic effect was achieved with Lewis-acids. By means of FeCl3, a vinylester containing epoxide groups and CC-double-bonds is obtained, which polymerizes via various mechanisms.  相似文献   
106.
In a recent study it was reported that DNA could be taken up from the feed and transferred to the blood of Atlantic salmon (Nielsen CR, Berdal KG, Bakke-McKellep AM, Holst-Jensen A, Eur Food Res Tech, 2005). In the present study the transport in blood and accumulation in some organs of intravenously injected DNA was studied. Intravenous injection was used as an alternative to feeding to ensure that the quantity of target DNA would permit a quantitative study of the distribution and degradation of the DNA in the fish. Three DNA fragments of different length were administered by injection to 40 salmon, each in a copy number of 1010. Blood and tissues were sampled at different time intervals after injection. To ensure the use of a sensitive and reliable detection system, real-time PCR methods with TaqMan chemistry were applied in this study. Target DNA was observed in blood and all investigated tissues, with peak levels observed at 0.5–1 h after injection. Some tissue samples were positive for the target DNA up to 24 h after injection. Results of the present study indicate that dietary DNA taken up in the blood may be transported to organs like liver and kidney, as well as muscle and gonads.  相似文献   
107.
The emergence of highly interactive media and the increased connectivity among people call for an investigation of usage behaviour of those media. People tend to rely heavily on peer-to-peer interaction influencing the adoption of new media formats that enhance this interactivity. The first explorative phase of this research consists of interviews with experts and focus groups and builds the basis of the proposed framework and measurement model. Then, a Structural Equation Modelling approach is used to assess the relative importance and the strength between different constructs, including perceived enjoyment, social norm, usefulness, ease of use and intention to use. The results indicate that perceived enjoyment and social norm are important antecedents for the adoption of technology with network externalities.  相似文献   
108.
Although there are numerous potential benefits to diversity in work groups, converging dimensions of diversity often prevent groups from exploiting this potential. In a study of heterogeneous decision-making groups, the authors examined whether the disruptive effects of diversity faultlines can be overcome by convincing groups of the value of diversity. Groups were persuaded either of the value of diversity or the value of similarity for group performance, and they were provided with either homogeneous or heterogeneous information. As expected, informationally diverse groups performed better when they held pro-diversity rather than pro-similarity beliefs, whereas the performance of informationally homogeneous groups was unaffected by diversity beliefs. This effect was mediated by group-level information elaboration. Implications for diversity management in organizations are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
109.
No change here: Analysis with doubly labeled [(13)C(2)D(6)]DMSP and LC/MS revealed that dissolved DMSP is taken up and stored intracellularly by diverse phytoplankton species without transformation. This is even true for species that produce no quantifiable amounts of DMSP themselves.  相似文献   
110.
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