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101.
Thomas J. Brumm C. R. Hurburgh Jr. 《Journal of the American Oil Chemists' Society》1990,67(11):747-749
Drought stress created shriveled and wrinkled (S/W) soybeans in the 1988 soybean crop. Seven lots of 1988 soybeans were examined
to validate the Federal Grain Inspection Service (FGIS) definition of S/W. Lots were subdivided into sized fractions with
both slotted and round-hole screens. Shriveled and wrinkled soybeans were found in all size fractions, whether those fractions
were determined by a slotted or a round-hole screen. None of the size fractions adequately isolated or characterized S/W soybeans.
The FGIS definition of shriveled and wrinkled does not sonsider larger wrinkled soybeans, but only shriveled soybeans passing
through a 10/64″ by 3/4″ slotted screen. The most accurate determination of S/W soybeans can be made by examining the entire
soybean sample, not a sized fraction. 相似文献
102.
Desulphurization of fifteen US coals of rank ranging from anthracite to sub-bituminous B and five high-temperature chars by carbon monoxide and other gases and gas mixtures between 400 and 600 °C has been studied. The sulphur content of the parent coals ranged between 3.0 and 7.3% and that of the chars between 1.3 and 3.8% by weight. A comparison between air, nitrogen, carbon monoxide, and steam-carbon monoxide mixtures as desulphurizing gases shows the order of desulphurizing ability as . 相似文献
103.
R. J. Hron Sr. S. P. Koltun A. V. Graci Jr. 《Journal of the American Oil Chemists' Society》1982,59(5):233-237
The 1976 and 1977 crops of glanded cottonseed from oil mills located in 7 major U.S. cottonbelt growing areas were evaluated
as to their suitability for processing into edible, high-protein flours. Both the physical and chemical characteristics of
fuzzy seed samples were studied. Ginned seed samples were hulled, dried, comminuted, slurried with hexane and liquid classified
by both a laboratory differential settling test (DST) and pilot plant liquid cyclone process (LCP). Liquid cyclone operating
data and extensive analytical data of the kernels, flour and meals produced are shown. A free gossypol level of 1.10% or less
in full fat kernels was the determining factor for producing edible flours from glanded seed by the LCP. The Lower Rio Grande
Valley area was the only area from which liquid classified cottonseed flour consistently exceeded the current maximal free
gossypol standard of 450 ppm. Ca. 94% of the total U.S. cottonseed production is suitable for producing edible, high-protein
flours by liquid classification. 相似文献
104.
J. Mustafa M. S. Ahmad Jr. A. Rauf S. M. Osman 《Journal of the American Oil Chemists' Society》1990,67(12):937-939
Branched-chain thioethers have been prepared from methyl 4-oxo-trans-2-hexadecenoate and 9,12-dioxo-trans-10-octadecenoic acid. The reagents involved in these preparations were mercaptoacetic and mercaptopropionic acids. The yields
of these thioethers are almost quantitative. 相似文献
105.
Phenolic acids and related compounds were separated by gas chromatography using three separate columns. One of these columns was coupled to a Fourier transform infrared spectrometer. The trimethylsilyl derivatives could be separated and identified by comparing the relative retention times of the three different columns. However, where there was overlap, the accompanying infrared data clearly distinguished between the questionable derivatives, thus enabling characterization of all derivatives.The use of trade, firm, or corporation names in this article is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the U.S. Department of Agriculture or the Forest Service of any product or service to the exclusion of others that may be suitable. 相似文献
106.
G. SCOTT GLAESEMANN JOHN E. RITTER Jr. KARL JAKUS 《Journal of the American Ceramic Society》1987,70(9):630-636
Mixed-mode failure of soda-lime glass under inert and fatigue test conditions was studied using Knoop indentation flaws. For annealed cracks (residual stress-free) crack extension (catastrophic or subcritical) is by an abrupt transition from the initial crack plane to a noncoplanar crack plane followed by a reorientation of the crack normal to the applied stress. Although fatigue strength of these inclined flaws increased linearly with respect to orientation of the flaws to the applied stress up to an angle of 60°, this increase was considerably less than what was predicted by existing theories. It is believed that subcritical crack growth causes the crack to be realigned perpendicular to the applied stress before failure for all orientations; hence, fatigue strength does not show the dramatic increase at orientation angles as predicted by theory. For as-indented cracks the contact residual stress causes the crack extension to be less inclined to the initial crack plane than for annealed cracks, but in this case also, the crack realigns itself perpendicular to the applied stress. Again, fatigue strength is relatively insensitive to the orientation angle as predicted by theory and subcritical crack growth is believed to play a primary role in determining this strength dependency. 相似文献
107.
The Thermodynamic Properties of Silicon Oxynitride 总被引:1,自引:0,他引:1
A critical assessment of thermal and equilibrium data for silicon oxynitride (Si2 N2 O) is presented. Selected values for the heat of formation of Si2 N2 O from the elements and the absolute entropy of Si2 N2 O at 298.15 K are ΔH0 f,298 =−947.7 ± 5.4 kJ/mol and S0 298 = 45.35 ± 0.4 J/mol·K, respectively. A table of thermodynamic functions for Si2 N2 Ofrom 298 to 2500 K, which has been calculated from the analysis of the literature data, is also presented. 相似文献
108.
Reed M. Izatt Steven R. Izatt Don W. Mcbride Jr. Jerald S. Bradshaw James J. Christensen 《Israel journal of chemistry》1985,25(1):27-32
Macrocycle-mediated fluxes of Cd(NO3)2 and of several binary mixtures of Cd(NO3)2 with the nitrate salt of either Na+, K+, Rb+ Cs+, Ag+, Ca2+, Sr2+, Pb2+, Zn2+, or Cu2+ have been determined in a H2O-CHCl3–H2O liquid membrane system. Of the macrocycles studied, 2.2 and 2.2DD most successfully transported Cd2+ In the Cd2+–Mn+ mixtures, Cd2+ was transported selectively with 2.2 when Mn+ was either an alkali or an alkaline earth cation. However, when Mn+ was either Ag+, Pb2+, or Cu2+ the Cd2+ flux was reduced sharply. Generally, cation flux was greater for 2.2DD than for 2.2 with selectivity for Cd2+ being altered also in several cases. Relative fluxes from binary cation mixtures depend on metal cation radius, macrocycle cavity diameter, ligand ring substituent and log K for metal ion-macrocycle interaction. 相似文献
109.
T. J. WEiss Mona Brown H. J. Zeringue Jr. R. O. Feuge 《Journal of the American Oil Chemists' Society》1971,48(4):145-148
Thin layer chromatography was adapted for direct quantitative estimation of sucrose esters of palmitic acid. Urea-phosphoric
acid spray was used to detect the sucrose moiety of the various esters. The photometrically metermined density density of
each spot on the thin layer plate was found to be proportional to its sucrose content. Ester content was then obtained by
multiplying sucrose found by the factor, mol. wt. ester/mol. wt. sucrose. Ester mixtures were prepared by interesterifying
sucrose with various proportions of methyl palmitate in dimethylformamide solution. Positional isomers were observed at each
level of substitution but could not be adequately separated from each other for quantitative evaluation.
Presented at the AOCS Meeting, Minneapolis, October 1969.
So. Utiliz. Res. Dev. Div., ARS, USDA. 相似文献
110.
C. E. Warburton Jr. 《The Journal of Adhesion》1975,7(2):109-119
The effectiveness of ethyl or butyl acrylate copolymerized with a small proportion of acrylonitrile in improving crockfastness of pigment-printed textile fabrics was determined. Crockfastness was demonstrated to be dependent upon mechanical resistance of the pigmented binder to rubbing and adhesion of the binder to fabric. Crockfastness on cotton fabrics correlated with tensile properties of binder films, ethyl acrylate being superior to butyl acrylate. The correlation failed with polyester fabric because adhesion was a more critical factor, the polyester fiber and yarn surfaces being smoother and more difficult to wet thermodynamically than cotton; in this case, butyl acrylate was superior to ethyl acrylate in adhesion and crockfastness. An analysis of surface free energies showed that better adhesion of the butyl acrylate copolymer to polyester was a consequence of lower total surface energy and lower polarity. 相似文献