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941.
The clarification of apple juice with the use of honey and enzyme separately and in combinations was studied. The results indicated the existence of a synergistic effect upon the time of initial flocculation when honey was combined with pectinase enzymes. Changes in the rate of flocculation appeared to be an additive effect of enzyme concentration and/or honey concentration. The combined treatment of honey and enzyme was found to induce flocculation very fast as compared to enzyme alone at cold as well as warm temperatures. When used alone, the honey treatment produced a clarified juice with a viscosity similar to cider.  相似文献   
942.
Calcium propionate was incorporated into a complete poultry feed and a feed concentrate at levels of 0, 0.3, 0.4 and 0.6%. The feeds were stored in 25 kg woven sacks in a feed mill. Air temperatures ranged from 22 to 34°C and relative humidity was in the range 67 to 93%. Mould growth was measured microbiologically and by measurement of feed temperature. Calcium propionate had a large effect on the microbiological measurements but only a small effect on heating in the feeds. As a preservative, it retained its activity for 6 weeks which extended the storage life by only 1 week in this case. The relative merits of the microbiological and temperature measurements are discussed.  相似文献   
943.
The solvent aspects of exposure to ethylbenzene are reviewed via an initial examination of the production, use, occurrence, and disposition of ethylbenzene as well as populations potentially at risk. While occupational exposure to ethylbenzene during its production and subsequent conversion to styrene is believed to be minimal, the broader occupational exposure to ethylbenzene during the production and use of 'mixed xylenes' is another area of concern. The general public can be exposed to ethylbenzene in ambient air as a result of its occurrence in motor vehicle exhaust. Additional exposure can arise in indoor environments, mostly from passive exposure to cigarette smoke. Ethylbenzene is primarily an irritant to the skin and mucous membranes and possesses narcotic properties at high concentrations.  相似文献   
944.
A comb-generating laser suitable for DWDM application is demonstrated on the basis of a multimode quantum-dot laser. Bit error rate < 10-13 at 10 Gbit/s external modulation was measured for 10 longitudinal modes owing to low (<0.3% over 0.001-10 GHz) relative intensity noise of each individual mode.  相似文献   
945.
946.
A consistent modelling scheme for digital images is presented, with the grey-level raster image as input and the list-oriented polygonal image as output. The output information consists of two parts: The metric of the polygonal object, represented by coordinates of marked positions, and the global topology, which takes the form of a two-dimensional topologic order. The central problem, which has to be solved, is to select a digital polygon, approximating a digital arc such that the essential feature of the arc is represented at a predefined precision level. The proposed algorithm uses simple incremental calculations of INTEGER quantities to solve the problem.  相似文献   
947.
948.
Dr. W. Mack 《Acta Mechanica》1989,77(1-2):91-99
Summary The axisymmetric bulging of circular cylindrical rubber bars under end thrust is investigated. The results for different forms of the strain energy function are compared with experimental results.With 2 Figures  相似文献   
949.
A flow reaction system was developed to study the steady state kinetics of hydrogen evolution in the presence of Ru(bipy)2+, MV+2, EDTA and a heterogeneous supported catalyst. Under the conditions used, steady state rates similar to those previously reported with colloidal Pt particles were attained. Furthermore, over much of the range of concentrations used, the reaction was zero order and it did not exhibit an Arrhenius behavior. Examination of the various rate determining steps involved led us to conclude that surface processes such as the recombination and desorption of hydrogen from the Pt surface might be rate determining.  相似文献   
950.
A 24-year-old woman suffered from ano-rectal Crohn's disease and nephrotic syndrome due to glomerular amyloidosis AA. She received azathioprine and colchicine for two years. Both Crohn's disease and nephrotic syndrome resolved. However amyloid renal lesions were still present. This course is exceptional, and leads to a discussion of the treatment of amyloidosis associated with Crohn's disease.  相似文献   
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