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51.
Colloidal dispersions of uniform spherical particles of yttrium basic carbonate and rodlike particles of yttrium ammine carbonate were prepared by aging at elevated temperatures yttrium salt solutions in the presence of urea. Different composition and morphology were achieved by altering the aging temperature and time. Coprecipitation in mixed solutions of yttrium(III) and cerium(III) salts under similar experimental conditions yielded composite spherical particles of basic carbonate. The content of the two metals in the solids followed closely the initial composition of the reacting solutions. On calcination all prepared solids converted to their corresponding oxides while retaining their particle morphology. The so-prepared powders were characterized by various techniques. 相似文献
52.
TERRY L RISS PETER J. BECHTEL RICHARD M. FORBES BARBARA P. KLEIN FLOYD K. McKElTH 《Journal of food science》1983,48(6):1868-1869
The nutrient content of special fed veal (SFV) was analyzed and compared to previously reported values for veal and beef. Ribeyes of SFV from 8 different U.S. producers were analyzed for moisture, total fat, protein, cholesterol, folacin, thiamin, riboflavin, niacin, B6, B12, vitamin A, pantothenic acid, 16 amino acids and 8 minerals. Special fed veal was found to be similar in nutrient content to reported values for beef and veal with one exception; the Fe content of SFV was 14–25% of reported values for beef. 相似文献
53.
54.
PETER G. HARRIS 《International Journal of Dairy Technology》1982,35(3):104-108
A survey of 8,749 people was conducted in Great Britain to determine the percentage of those who limited or avoided consumption of cow's milk for reasons other than financial. Those who limited or avoided cow's milk consumption were further questioned to determine whether their reasons were perceived by them to relate to allergy/lactose intolerance. Of the sample population 1.47% limited or avoided cow's milk consumption for reasons that might possibly be related to allergy/lactose intolerance . 相似文献
55.
PETER W. VOISEY 《Journal of texture studies》1971,2(2):129-195
Abstract. The use of electronic instruments to record force and deformation in objective texture measurements is reviewed to point out that much equipment is available for that purpose and to indicate some of the problems associated with its use. Electronic transducers are universally applicable to texture measuring systems and can give precise measurements with a high degree of resolution. Several examples of modernized texture instruments are described to demonstrate different methods of approach. Special purpose or ‘universal units’ can be developed. It is concluded that force and deformation can be recorded by electronic techniques in any textural test but that the interpretation of the data is the major problem. 相似文献
56.
ANTENNAL AND BEHAVIORAL RESPONSES OF GRAPEVINE MOTH <Emphasis Type="Italic">Lobesia botrana</Emphasis> FEMALES TO VOLATILES FROM GRAPEVINE 总被引:2,自引:0,他引:2
Tasin M Anfora G Ioriatti C Carlin S De Cristofaro A Schmidt S Bengtsson M Versini G Witzgall P 《Journal of chemical ecology》2005,31(1):77-87
Grapevine moth Lobesia botrana is the economically most important insect of grapevine Vitis vinifera in Europe. Flower buds, flowers, and green berries of Chardonnay grapevine are known to attract L. botrana for oviposition. The volatile compounds collected from these phenological stages were studied by gas chromatography—mass spectrometry, and the antennal response of L. botrana females to these headspace collections was recorded by gas chromatography—electroantennography. The compounds found in all phenological stages, which consistently elicited a strong antennal response, were pentadecane, nonanal, and -farnesene. In a wind tunnel, gravid L. botrana females flew upwind to green grapes, as well as to headspace collections from these berries released by a piezoelectric sprayer release device. However, no females landed at the source of headspace volatiles, possibly due to inappropriate concentrations or biased ratios of compounds in the headspace extracts. 相似文献
57.
PETER R. SEGATTO 《Journal of the American Ceramic Society》1960,43(5):278-281
A rapid method for the determination of boron in borosilicate glasses by neutron transmission has been developed. The glass sample is dissolved in 48% HF, placed in a polyethylene cell which is located near a Ra-Be neutron source. The neutron source and sample cell are embedded in a parafEn moderator. The attenuation of the neutron flux, which can be related to the boron concentration in the cell, is monitored with a BF3 enriched B10 proportional counter. Boron determinations can be made in approximately 40 minutes with an accuracy of ±%. Owing to the low sensitivity (approximately 1 mg.) the major disadvantage of the method is the large sample size necessary. The method, however, is well suited for use as a quality control procedure. 相似文献
58.
PETER W. VOISEY 《Journal of texture studies》1975,6(2):253-257
Abstract . Since mastication involves high deformation rates (150cm min?1), the arbitrarily selected slow deformation rates usually used in instrumental texture tests can lead to erroneous results and lack of correlation with sensory evaluation with respect to the order of sample ranking. Sophisticated instrumentation that is costly to operate is required to accurately simulate the deformation rates operating in the mouth. It is suggested that instrumental data obtained at slow rates could be evaluated in a more meaningful manner if series of similar samples were tested at increasing deformation rates and the plotted force/deformation curves extrapolated to 150cm min?1. It is implied that recording systems would be more useful, if in addition to force, they sensed the rate of force change with deformation rate. 相似文献
59.
60.
Abstract. Different methods used to measure pea tenderness are reviewed. Objective estimation of crop maturity, pea tenderness and quality has concerned researchers for many years. Chemical and mechanical methods have been used, and several instruments developed. There is a high degree of correlation between methods which also appear to agree with sensory analysis. For grading peas to establish the price paid to the grower, accuracy and economy under commercial conditions is of prime importance. Some methods are unsuitable on this basis, and presently used instruments and the manner in which they are operated require improvement. 相似文献