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981.
The viscosity and apparent molar volume of solutions of KBrO3, NaBrO3 KIO3, NaIO3, K2SO4 and Na2SO4 in dioxane (mass fraction: 10, 20 and 30%)-water mixtures at 30, 35, 40 and 45°C have been measured. The ions appear to interact appreciably and the ion-solvent interaction is of the order BrO?3 > IO?3 > SO2?4 and K+ > Na+.  相似文献   
982.
Tungsten oxide (WO3) nanorods array prepared using chemical vapor deposition techniques was studied. The influence of oxygen gas concentration on the nanoscale tungsten oxide structure was observed; it was responsible for the stoichiometric and morphology variation from nanoscale particle to nanorods array. Experimental results also indicated that the deposition temperature was highly related to the morphology; the chemical structure, however, was stable. The evolution of the crystalline structure and surface morphology was analyzed by scanning electron microscopy, Raman spectra and X-ray diffraction approaches. The stoichiometric variation was indicated by energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy.  相似文献   
983.
With model dyes and chemicals, some basic physico-chemical phenomena of solvent dyeing are examined. Starting with properties of the solvents, different interactions between solvents and fibres, dyes and chemicals are described and the influence on the dyeing result is discussed. In conclusion, work on establishing solvent dyeing is considered as a stimulus to dyeing technology as a whole.  相似文献   
984.
985.
A dilatometric technique was used to determine the total evaporation time of individual drops of furan, isopentane and cyclopentane as they rose in water. The values of total evaporation time were predicted reasonably well for each system by a different equation than was used to correlate the evaporative data for the initial 10% of the evaporative process as reported in Part I of this study. The total evaporation time data were also compared with the correlations given by Klipstein (1), by Sideman and Taitel (2) and with the correlation which was found by the authors to best fit the total evaporative data for the three systems. In agreement with Klipstein (1), the correlation for the overall heat transfer coefficient was found to be one of the form, qA = Cd12.0δt. The rate of rise of an evaporating drop for the conditions used in this study was found to be nearly equal to the instantaneous terminal velocity.  相似文献   
986.
Summary Data are presented which show the effects of different solvents on the yield and properties of liquid wax fromSimondsia chinensis (jojoba) and on the characteristics of the hydrogenated waxes obtained from the liquid waxes. Three reagent grade solvents, carbon tetrachloride, benzene, and isopropyl alcohol, and three commercial grade solvents, heptane, hexane, and tetrachloroethylene, were evaluated as extractants for the liquid wax from jojoba. Soxhlet-type of extractions were carried out under conditions in which the solvent was the only significant variable. Four of the solvents extracted essentially the same amount of material from the seed while isopropyl alcohol extracted significantly more material and tetrachloroethylene significantly less. Obviously the difficulties involved in separating the solids recovered from the isopropyl alcohol extraction preclude its use as the extracting solvent for jojoba wax. The density of the liquid waxes varies from 0.8631 to 0.8648; the waxes from the tetrachloroethylene and hexane extractions had the lowest value and the wax from isopropyl alcohol the highest. In each case, regardless of the solvent used, a precipitate developed in the liquid wax after it had been desolventized and stored for 7–10 days. Hydrogenation of clear fractions and precipitate containing fractions of these liquid waxes showed that the precipitate had no apparent effect upon the melting point or hardness of the resulting solid wax. Some of the liquid waxes required a longer hydrogenation time to attain an iodine value of about 1. At this iodine value all of the solid waxes had melting points between 66 and 68°C. Hardness values of all the solid waxes as measured by the Trionic hardness gauge were 90. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.  相似文献   
987.
988.
A hybrid plant consisting of a diesel driven vapor compression unit and a steam ejector - vapor compression MES unit will have a very low specific primary energy consumption.This paper discusses results of experiments concerning critical parts of such a concept as well as some results of numerical calculations.The experiments were expecially concerned with brine distribution by sieve trays in the MES-unit and with the behaviour of such units under different but steady state load conditions  相似文献   
989.
990.
The composition of the lipids of two samples of krill and one of “red crab” was determined by thin layer, column and gas chromatographic procedures. A large number of unusual fatty acids were present.  相似文献   
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