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51.
A range of yellow fluorescent 2-pyrazoline acid dyes has been synthesized. Their spectral and dyeing properties (on wool and nylon) depend both on the nature of the substitution pattern of the dye and on the nature of the fibre substrate. Exhaustion and fastness to washing, which are better on nylon than on wool, are improved by substituents attached to the 2-pyrazoline ring. Fastness to light is independent of the fibre and is increased by substituents on the 4- and 5- positions of the 2-pyrazoline ring. The fastness properties of the pyrazoline dyes were compared with those of C.I. Acid Yellow 7. 相似文献
52.
Abstract Twenty one tenderometers were compared in processing plants for their accuracy of measurement using wax wafers as the test material. The results indicate that there are serious differences among the tenderometers and that the accuracy of measurement is unsatisfactory for the purpose of grading peas to establish the price paid to the grower. If a relationship of compatible trust is to remain between the processor and the grower, serious consideration must be given either to better calibration of currently used tenderometers or to devising some other method of grading and paying for peas. 相似文献
53.
PETER J. WYLLIE 《Journal of the American Ceramic Society》1967,50(1):43-46
Conditions for crystallization of calcite from melts in the presence of a vapor or gaseous phase are reviewed to provide possible guidelines for growth of calcite. Phase equilibrium data for the system CaO-CO2 show that to precipitate calcite from molten CaCO3 the temperature must be above 1230° C and excess CO2 must be present at pressures greater than 39.5 bars. Phase equilibrium data for the system CaO-CO2 -H2 O show that calcite can be precipitated from melts at 650°C in the presence of an aqueous vapor phase at 10 bars or more. Crystallization can be induced either by introducing temperature variations, or by changing the composition of the coexisting aqueous vapor phase under isobaric, isothermal conditions. The system CaO-MgO-CO2 -H2 O is used to show that doped calcite crystals, Cax R1 -x CO3 , could be precipitated, with precisely controlled compositions, from melts in the system CaO-RO-CO2 -H2 O. Apatite phase relations are also presented. 相似文献
54.
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
55.
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
56.
57.
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
58.
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
59.
60.
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