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961.
Robert A. Moreau David B. Johnston Kevin B. Hicks 《Journal of the American Oil Chemists' Society》2007,84(11):1039-1044
All commercial corn oil is obtained by pressing corn germ and/or extracting the germ with hexane. In the current study, six
types of corn oil were prepared by extracting corn germ, corn fiber and ground corn, each with hexane or with ethanol. The
levels of lutein, zeaxanthin and other carotenoids were quantitatively analyzed in the six corn oils. The levels of lutein + zeaxanthin
in the oil ranged from 2.3 μg/g for hexane-extracted corn germ oil to 220.9 μg/g for ethanol-extracted ground corn oil. These
results indicate that a diet that includes 30 g (~2 tbsp) per day of the unrefined corn oil obtained by extracting ground
corn with ethanol would provide ~6 mg of lutein + zeaxanthin, the daily dosage that is currently considered to be necessary
to slow the progression of age-related macular degeneration.
Mention of trade names or commercial products in this publication is solely for the purpose of providing specific information
and does not imply recommendation or endorsement by the U.S. Department of Agriculture. 相似文献
962.
We studied lipid metabolism and the antioxidant defense system in plasma and liver of rats fed diets supplemented with l
ω-nitro-l-arginine methyl ester (l-NAME), isosorbide dinitrate (DIS), l-arginine (Arg), or the associations of these drugs. Liver hydroperoxide and thiobarbituric-acid-reactive substance (TBARS)
levels were decreased by Arg and increased by l-NAME or DIS treatments. Oxidized glutathione and conjugated dienes were increased by DIS. Nitrate + nitrite levels and serum
calcium ([Ca++]) were incremented by Arg or DIS and reduced by l-NAME. Superoxide dismutase and catalase activities decreased under Arg treatment, while l-NAME or DIS caused stimulation. Liver high-density lipoprotein (HDL) cholesterol was increased by DIS or NAME (alone or associated
with Arg). Free fatty acids and neutral and polar lipids were increased by Arg, l-NAME, and DIS. However, predominating phospholipid synthesis increased the neutral/polar ratio. Decreased levels of nitric
oxide (NO) (low [Ca++]) was directly associated with increased fatty acid synthetase, decreased phospholipase A2, carnitine-palmitoyl transferase, and fatty acid desaturase activities. Raised NO (high [Ca++]) inversely correlated with increased phospholipase-A2 and acyl-coenzyme A (CoA) synthetase and decreased fatty acid synthetase and β-oxidation rate. Arg or DIS produced changes
that were partially reverted by association with l-NAME. Based on these observations, prolonged therapeutical approaches using drugs that modify NO availability should be carefully
considered.
Julio Nella author in memoriam. 相似文献
963.
Composites consisting of carbon fibers (CF) and carbon particles (CP) in polypropylene (PP) matrix were melt-compounded. Composites
were analyzed for their mechanical, electrical and thermal properties. Results indicate that the addition of these fillers
improved the mechanical properties of the composites. Thermal conductivity was enhanced as the concentration of fillers was
increased. Carbon fibers render the composites electrically conductive so we observed a percolation threshold near 10 wt.%
of CF for PP/CF (PP and CF composite) and near 25 wt.% of CP for PP/CP (PP and carbon particle composite). All the results
indicated that carbon fibers are more effective in improving the properties as compare to the carbon particles. 相似文献
964.
The vast majority of studies of plant indirect defense strategies have considered simple tritrophic systems that involve plant
responses to attack by a single herbivore species. However, responses by predators and parasitoids to specific, herbivore-induced,
volatile blends could be compromised when two or more different herbivores are feeding on the same plant. In Y-tube olfactometer
studies, we investigated the responses of an aphid parasitoid, Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae), to odors from cabbage plants infested with the peach-potato aphid Myzus persicae (Sulzer) (Homoptera: Aphididae), in both the presence and absence of a lepidopteran caterpillar, Plutella xylostella L. (Lepidoptera: Plutellidae). Female parasitoids chose aphid-infested plants over uninfested plants but did not distinguish
between caterpillar-infested and uninfested plants. When given a choice between odors from an aphid-infested plant and those
from a plant infested with diamondback moth larvae, they significantly chose the former. Furthermore, the parasitoids responded
equally to odors from a plant infested with aphids only and those from a plant infested with both aphids and caterpillars.
The results support the hypothesis that the aphid and the caterpillar induce different changes in the volatile profile of
cabbage plants and that D. rapae females readily distinguish between the two. Furthermore, the changes to the plant volatile profile induced by the caterpillar
damage did not hinder the responses of the parasitoid to aphid-induced signals. 相似文献
965.
ChangKyoo Yoo Tae Young Lee Jiyong Kim Il Moon Jae Hak Jung Chonghun Han Jong-Min Oh In-Beum Lee 《Korean Journal of Chemical Engineering》2007,24(4):567-576
This article considers new and existing technologies for water reuse networks for water and wastewater minimization. For the
systematic design of water reuse networks, the theory of the water pinch methodology and the mathematical optimization are
described, which are proved to be effective in identifying water reuse opportunities. As alternative solutions, evolutionary
solutions and stochastic design approaches to water system design are also illustrated. And the project work flow and an example
in a real plant are examined. Finally, as development is in the forefront in process industries, this paper will also explore
some research challenges encountered in this field such as simultaneous water and energy minimization, energy-pinch design,
and eco-industrial parks (EIP). 相似文献
966.
Hyun Jung Seung-Min Paek Joo-Byoung Yoon Jin-Ho Choy 《Journal of Porous Materials》2007,14(4):369-377
The ZrO2-pillared clay with high acidic property has been prepared by reacting 1 wt% colloidal suspension of Na+-montmorillonite with 1 N aqueous solution of ZrOCl2·8H2O and by subsequent heating. The evolution of local structure around zirconium of the intercalant stabilized in-between aluminosilicate layers upon intercalating, drying, and pillaring condition has been systematically studied by X-ray absorption spectroscopy, and compared to those of reference compounds such as ZrO2, and ZrOCl2 · 8H2O and its 1 N aqueous solution. The intercalated zirconium species was identified as the Zr-tetramer, [Zr4(OH)14(H2O)10]2+, with an average molecular volume of 10 × 10 Å2 and a thickness of 4.5 Å. Also it becomes more condensed upon drying and eventually transforms to a zirconium oxide pillar upon calcination. 相似文献
967.
Márcia Campos Brasil Annelise Engel Gerbase Maria Augusta de Luca José Ribeiro Gregório 《Journal of the American Oil Chemists' Society》2007,84(3):289-295
Hybrid organic–inorganic films were prepared using four different hydroxylated soybean oils (HSO) or epoxidized soybean oil
as organic precursor and tetraethyl orthosilicate (TEOS) as inorganic precursor in a mass ratio of HSO:TEOS of 90:10. The
films were macroscopically homogeneous and were characterized by swelling and extraction in solvent, thermogravimetric analysis
(TGA), scanning electron microscopy (SEM) including energy dispersive spectroscopy (EDX), adhesion and hardness. Their properties
varied as a function of the number of OH groups present in the HSO. The best hybrid system was HSOF198/TEOS, with an OH value
of 198 mg of KOH/g, which presents lower swelling coefficient, very good adhesion on aluminium surface and good hardness. 相似文献
968.
Decomposition and nutrient release from pruning residues of two indigenous agroforestry species during the wet and dry seasons 总被引:1,自引:0,他引:1
Tesfay Teklay 《Nutrient Cycling in Agroecosystems》2007,77(2):115-126
The decomposition of leaves from Cordia africana Lam. and Albizia gummifera G. F.Gmel was investigated during the wet and dry seasons at Wondo Genet (Ethiopia). Litterbags of leaves were buried in
soils under farmland and shaded-coffee agroforestry systems. Residual matter was recovered after 4, 8, 12, and 16 weeks and
analysed for nitrogen (N), phosphorus (P), potassium (K), cellulose, lignin, soluble polyphenol and condensed tannin content.
Mass-loss and release of N, polyphenols and condensed tannins were greater from Albizia leaves than from Cordia leaves, suggesting that a high polyphenol content does not necessarily retard decomposition. The rates of mass loss and release
of the majority of leaf constituents were considerably faster during the wet season than during the dry season. Lignin decomposition,
however, proceeded more rapidly during the dry season, and no significant seasonal differences were observed for polyphenol
decomposition. The decomposition kinetics of most leaf components during the wet season were best described by a single-exponential
model, but a quadratic model provided the best fit during the dry season. Initial leaf chemistry and season were important
decomposition factors, while land-use effects were negligible. However, land-use effects showed distinct seasonal differences,
with leaf litter decomposing more rapidly in soil under shaded-coffee than under farmland management, especially during the
wet season. This study also demonstrated that polyphenol content does not show the predictive effects it has been attributed
to have and that other constituents, such as condensed tannins, would be better suited for this purpose. 相似文献
969.
The pulsed arc discharge to the surface of wastewater was applied to the degradation of a textile azo dye (Acid Red 27). A
high-voltage electrode (discharging electrode) was vertically placed above the surface of the wastewater while the wastewater
itself was grounded. The pulsed arc discharge occurred between the tip of the discharging electrode and the surface of the
wastewater, producing various oxidative species. Oxygen was used as the working gas instead of air to prevent nitrogen oxides
from forming. The effect of several parameters on the chromaticity and chemical oxygen demand (COD) removal was examined.
The results obtained showed that the chromaticity of the wastewater was completely removed by this process and the COD also
decreased significantly. It has been found that ozone formed in the gas phase mainly affects the removal of the dye. The contribution
of other effects such as ultraviolet light emission and OH radical formation during the arc discharge to the degradation of
the dye was found to be less than 15%. For the present reactor system, the optimum pH, pulse repetition rate and agitation
speed were found to be 3.0, 110 Hz and 300 rpm, respectively. 相似文献
970.
Adsorption of anionic dyes on the cross-linked with epichlorohydrin starches containing quaternary ammonium groups (CCS) was
investigated and compared with that of modified starches containing only quaternary ammonium groups (CS). The adsorption of
anionic dyes on CS and CCS closely follows the Langmuir model of adsorption. The computed Langmuir saturation capacity Q
o increases with increasing degree of substitution (DS) of CS or CCS and has the value from 0.81 mol/kg to 3.22 mol/kg for
CCS and from 0.88 mol/kg to 1.87 mol/kg for CS. The effectiveness of the cationic groups in dye binding was about 1 mol/equiv
for CSS with DS from 0.47 to 0.62 and all the cationic groups had attached one anionic groups of the dye. Increasing DS of
CS decreases the effectiveness of dye binding due to the increase in solubility of CS, and the soluble part of CS binds the
dye as a typical soluble polyelectrolyte. CCS are more suitable than CS for the anionic dye adsorption from a textile dyeing
solution. DS of CCS should be about 0.5–0.6. They adsorb the anionic dyes in few minutes and acts in the wide range of pH
of the solutions. The Langmuir saturation capacity Q
o and the effectiveness of the cationic groups in dye binding increase with an increase of the adsorption temperature. The
positive values of the enthalpy and entropy suggest that the adsorption is endothermic and during the adsorption of the anionic
dye on CCS the randomness of the system increases. 相似文献