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91.
Charlotte H. Boatner 《Journal of the American Oil Chemists' Society》1944,21(1):10-15
Summary A method for the purification of gossypol has been developed which yields material differing in optical properties from those
previously reported for gossypol preparations. A colorimetric test for extractable gossypol has been described.
It has been shown that cottonseed contains at least three pigments in addition to gossypol. Some of the properties of the
three pigments have been reported. One of these newly detected pigments, gossypurpurin, has been shown to be the substance
which, mixed with gossypol, constitutes the so-called “red gossypol” of Podol’skaja.
The frequently reported water-dispersable blue pigment of cottonseed has been shown to be either a complex of gossypol, gossypurpurin
and protein or a mixture of two protein-pigment complexes. Its dissociation into the two pigments and protein has been accomplished.
Presented before the 34th Annual Meeting of the American Oil Chemists’ Society, New Orleans, Louisiana, May 12–14, 1943. 相似文献
92.
93.
The expansion of district heating into areas of low heat densities (heat sparse areas) constitutes a challenge due to the higher distribution costs. The profitability of sparse district heating has been analysed from actual investments in 74 areas with 3227 one-family houses connected to district heating between 2000 and 2004 in Göteborg, Sweden. The profitability was estimated from a probable price model, a typical marginal heat generation cost, and the investments from the actual connections made. The analysis identified factors as the linear heat density and heat sold per house explaining the main variations in profitability. The profitability analysis was concluded with a competition analysis. The main conclusion is that sparse district heating is possible when reaching low investment costs for the local distribution network and low marginal costs for the heat generation. In Sweden, the general competitiveness of sparse district heating is facilitated by the high consumption taxes for fuel oil, natural gas, and electricity. Hence, it should be more difficult to introduce sparse district heating in other countries with low energy taxes. 相似文献
94.
Evolutionary stable strategy (ESS) theory was tested on the handedness composition of major league baseball (MLB) players. The throwing handedness of pitchers and the hitting handedness of batters were sampled over 110 yrs and their proportions analyzed over decades. Then, to predict steady-state laterality levels, ESS equations were derived from a payoff matrix of hitting performances for left-right pitcher-batter confrontations (J. Thorn and P. Palmer, 1985). The equations successfully predicted a pitcher-batter invasion in which left-handed pitchers would stabilize at about 31% of the population. For batters, the predictions were 27% left-handed, 11% bats with both hands, and 63% right-handed, accurate within a 3% margin of error. These successful predictions, based on nonarbitrary common-currency values in the payoff matrix, support the validity of ESS, while the use of handedness, a behavior influenced by phylogenetic, ontogenetic, and cultural factors, establishes its generality. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
95.
Contends that the ideal program of research to maximize clinical relevance combines 4 models of strategies. These are (1) convergent/convergent, (2) divergent/divergent, (3) divergent-theory/convergent-method, and (4) convergent-theory/divergent-method, and all are employed nomothetically at the level of theory and idiographically at the level of method. Model 1 serves to expand theoretical and procedural possibilities, giving clinicians the flexibility they need when working with individuals in service-delivery settings. Model 2 controls theoretical expansion. Model 3 controls procedural expansion. Model 4 may be used to provide preliminary demonstrations of feasibility that are then used to stimulate other forms of more directly relevant investigation. The products of this overall program of research will increasingly represent a useful body of tested theoretical and procedural possibilities and alternatives that clinicians can use for explaining and treating individual clients and for evaluating treatment outcomes in individually relevant terms. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
Local operators are used to detect linear features in Landsat data for an area where such features are typically less than 1 pixel in width. A modification to existing techniques is made which gives improved results. The choice of threshold for the detector algorithm is investigated by considering line and background intensity, linewidths, and line alignment with respect to the pixel boundaries and spatial autocorrelation in the data set. It is found that results will always contain a significant amount of noise. Two postprocessing techniques are described which reduce this noise by utilizing contextual information in the data. 相似文献
97.
Michael J. Frampton Giuseppe Sforazzini Sergio Brovelli Gianluca Latini Emily Townsend Charlotte C. Williams Ana Charas Leszek Zalewski Naeem S. Kaka Mallena Sirish Lisa J. Parrott Joanne S. Wilson Franco Cacialli Harry L. Anderson 《Advanced functional materials》2008,18(21):3367-3376
Hydrophilic polyanionic conjugated polyrotaxanes are readily synthesized in water by Suzuki coupling, but their high polarity and ionic nature limit the potential applications of these materials. Here, we demonstrate three methods for transforming these polar polyelectrolytes into nonpolar lipophilic insulated molecular wires. A water‐soluble polyfluorene‐alt‐biphenylene β‐cyclodextrin (CD) polyrotaxane was converted into nonpolar derivatives by methylation of the carboxylic acid groups with diazomethane and conversion of the hydroxyl groups of the CDs to benzyl ethers, trihexylsilyl ethers, benzoyl esters, and butanoate esters to yield polyrotaxanes that are soluble in organic solvents such as chloroform and cyclohexane. Elemental analysis, NMR spectroscopy, and gel permeation chromatography (GPC) data support the proposed structures of the organic‐soluble polyrotaxanes. The extents of reaction of the polyrotaxane CD hydroxyl groups were 55% for trihexylsilyl chloride/imidazole; 81% for benzyl chloride/sodium hydride; 72% for benzoyl chloride/pyridine/4‐dimethylaminopyridine; and 98% butanoic anhydride/pyridine/4‐dimethylaminopyridine. Alkylation, silylation, and esterification increase the bulk of the encapsulating sheath, preventing interstrand aggregation, increasing the photoluminescence efficiency in the solid state and simplifying the time‐resolved fluorescence decay. The organic‐soluble polyrotaxanes were processed into polymer light‐emitting diodes (PLEDs) from solution in nonpolar organic solvents, thereby excluding ionic impurities from the active layer. 相似文献
98.
Mette Kristensen Lars F Østergaard Ulrich Halekoh Henry Jørgensen Charlotte Lauridsen Kirsten Brandt Susanne Bügel 《Journal of the science of food and agriculture》2008,88(12):2161-2172
BACKGROUND: Many consumers perceive organic foods as more nutritious than conventional foods. However, the existing evidence is insufficient to support or refute this belief. The purpose of the present study was to investigate the effect of three different model cultivation systems on selected major and trace element contents of dried foodstuffs (carrots, kale, peas, potatoes and apples) grown in two consecutive years, as well as mineral retention determined in 36 rats (second generation in a multi‐generation study) fed diets based on these foodstuffs from one year. RESULTS: Overall, there was no evident trend towards differences in element content of foodstuffs or diets due to the use of different cultivation systems, and differences between harvest years exceeded those seen between cultivation methods. Also, no significant differences in the retention of elements in rats fed diets derived from different cultivation systems were seen, since higher intake resulted in correspondingly higher excretion. CONCLUSION: This study does not support the belief that organically grown foodstuffs generally contain more major and trace elements than conventionally grown foodstuffs, nor does there appear to be an effect on the bioavailability of major and trace minerals in rats. Copyright © 2008 Society of Chemical Industry 相似文献
99.
The rheological properties of starch extracted from ten different species of tropical tuber crops were examined using a Bohlin rheometer. Suspensions with starch concentrations of 3, 4 and 5% were gelatinised at 75°C and fed into the rheometer cup. A C 25 measuring system was used and the heating rate was 1.5°C/min, heating schedule 75‐95ºC, holding at 95°C for 600 s, cooling to 35°C at 1.5ºC/min, holding for 3600 s. For strain sweep tests, the range of strain used was 0‐0.2% and the temperature of test was 35ºC. The data on viscosity, storage modulus (G′) and phase angle were obtained from the rheograms. The results indicated variability in the various properties of the different starches. However the results did not follow a definite trend. The viscosity of Colocasia starch was low while Canna edulis and yam starches had high viscosities. The storage modulus was also highest for Canna starch (70‐93 Pa) for 5% and gel strength was comparatively high for Canna edulis, Dioscorea esculenta and D. rotundata starches. The phase angle values followed the pattern of G′ and all the starch pastes were found to be elastic in nature at higher concentration. The wide variability in rheological properties can be useful in different applications of tuber starches. 相似文献
100.
Demonstration of the utility of biomarkers for dietary intake assessment; proline betaine as an example 下载免费PDF全文