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991.
Lamb carcasses of > 22 kg weight were not adversely affected by spray washing, but carcasses of < 22 kg weight were affected to some extent. Characteristics of carcasses significantly affected included the appearance of the fat in the crutch region and on the back, and the degree of flaccidity and dampness of the abdominal region. These faults were alleviated somewhat during refrigerated storage and consequently the faults detected in the experiments were probably not of commercial significance since, under pilot market tests in Europe, buyers did not find any faults in spray washed carcasses.  相似文献   
992.
The 226Ra and 228Ra content of the lichens Umbilicaria cylindrica, U. deusta, U. murina and U. hirsuta has been determined as a function of the growth altitude above sea level, based on data derived from material collected from localities in southwest Poland. These data are interpreted as graphs and formulae to show the influence of environmental factors, particularly altitude, on the concentration of 226Ra and 228Ra, and the coefficients of accumulation calculated.  相似文献   
993.
Truncation of CPC solar collectors and its effect on energy collection   总被引:1,自引:0,他引:1  
Analytic expressions are derived for the angular acceptance function of two-dimensional compound parabolic concentrator solar collectors (CPC's) of arbitrary degree of truncation. Taking into account the effect of truncation on both optical and thermal losses in real collectors, we also evaluate the increase in monthly and yearly collectible energy. Prior analyses that have ignored the correct behavior of the angular acceptance function at large angles for truncated collectors are shown to be in error by 0–2% in calculations of yearly collectible energy for stationary collectors.  相似文献   
994.
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996.
Fouling is a major problem in membrane processes of water treatment. It can be caused by the deposition of inorganic and organic particulate material, and of microbial cells which may subsequently form biofilms. In practice, usually more than one foulant participates in the formation of membrane deposits. Knowledge of the composition of fouling layers is important for the development of appropriate countermeasures. For this purpose, an experimental system was established for the generation and microscopic visualisation of mixed deposits, using fluorescently labelled model foulants: (i) drinking-water bacteria stained with nucleic acid-specific dyes (biofouling), (ii) synthetic clay mineral laponite stained with rhodamine 6G (inorganic particle fouling), and (iii) fluorescently labelled polystyrene microspheres (organic particle fouling). Polycarbonate and polyethersulfone membranes were challenged with these foulants by dead-end filtration. On the basis of different fluorescent labels, the single foulants in these mixed deposits could be visualised separately by confocal laser scanning microscopy which, in combination with image analysis, allowed the generation of three-dimensional views of the complete deposits. This method offers the possibility for the estimation of quantitative surface coverage by foulants and for the determination of the efficacy of cleaning measures with respect to the removal of different foulants.  相似文献   
997.
Calculations of propagation constants for lossy materials are performed under the approximations of low loss (or high conductivity). To improve the understanding and better predict the analysis of such materials, exact formulation for wave impedance and propagation constants of homogeneous, lossy, dielectric/magnetic materials are proposed. Formulation is based on dielectric and/or magnetic loss tangent of the material  相似文献   
998.
The dependence of the cetane number of hydrotreated light cycle oil on chemical composition has been investigated. Cetane number was related to hydrogen content and aromaticity. The latter was determined by high performance liquid chromatography and also by carbon-13 n.m.r. spectroscopy. Specific correlations were developed in each case and a regression coefficient of 0.99 and a standard error of 1.25 were obtained for the best case. The usefulness of predicting cetane number from fuel composition is discussed.  相似文献   
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