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1.
Izabella Jackowska Monika Bojanowska Monika Staszowska-Karkut Monika Sachadyn-Król 《International Journal of Food Science & Technology》2019,54(12):3175-3184
Ozonation is an innovative way to preserve high quality of seed during storage and it is an alternative to harmful organophosphorus agents. Disclosure of changes in the rapeseed oil under the influence of oxidative action of ozone on the seeds was the aim of the work and is presented for the first time. Two ozone concentrations and different length of ozonation were applied. The changes in tocopherols, phenolics, flavonoids contents, antiradical activity and oxidative stability were examined. The average vitamin E concentration was 33 mg per 100 g of oil before and 31.7 after ozonation of seeds. The average content of phenolic compounds was 14.3 mg of sinapic acid g−1 and 16.9 after the ozone treatment. Changes in the flavonoids content and antioxidant activity were observed too. Ozonation caused a decrease in the vitamin E concentration which resulted also in reducing the quenching of free radicals and reduction of oil induction time. 相似文献
2.
3.
V. A. Roginsky T. K. Barsukova A. A. Remorova W. Bors 《Journal of the American Oil Chemists' Society》1996,73(6):777-786
The relative reactivities as well as the stoichiometric coefficients for a number of flavonoids, catechols, and—for comparison—standard
phenolic antioxidants were determined by analyzing the kinetics of oxygen consumption in organic and micellar systems, with
peroxidation initiated by lipid- and water-soluble azo initiators. The results demonstrated that the flavonoids did not behave
as classic phenolic antioxidants such as α-tocopherol, but showed only moderate chain-breaking activities. The results were
in line with other structure-activity relationship studies on the importance of the B-ring catechol structure, the 2,3-double
bond, and the 3,5-hydroxy groups. The data are discussed in view of possible explanations of the deviations flavonoids reveal
in their behavior compared with regular phenolic antioxidants. 相似文献
4.
Mohamed A. Mekewi 《Materials Research Innovations》2002,6(4):214-217
Polyisobutylene succinic anhydride-urea/polyamines (PIBSA) copolymers were synthesized as potential antioxidants and detergent
dispersant agents for lubricating oils samples (SAE-30). Homogeneity, thermal stability and dispersancy of the solutions were
determined. Fully soluble oil compounds that are thermally stable up to 250 °C were achieved.
The oxidation stability of lube oil samples in the presence of four designed PIBSA additives (varying in the number of amine
groups) was determined for a time period of up to 72 hours. The dependence of the additive efficiency on its concentration
was studied to achieve maximum stability. Some PIBSA additives at concentration 3.0 · 104 ppm exhibit the best results.
Dispersivity values were measured at predetermined oxidation times. The results proved reliable dispersion capability as the
nitrogen content of the additive is increased, i.e. the increase in the basic character of the additive leads to the increase
in the neutralization capability. Moreover, the designed PIBSA additives retain their efficiency after long oxidation times,
confirming their role as multifunctional nitrogen containing polymeric additive.
Electronic Publication 相似文献
5.
Robert O. Dunn 《Journal of the American Oil Chemists' Society》2005,82(5):381-387
Biodiesel, an alternative diesel fuel derived from transesterification of vegetable oils or animal fats, is composed of saturated
and unsaturated long-chain FA alkyl esters. During long-term storage, oxidation caused by contact with air (autoxidation)
presents a legitimate concern with respect to monitoring and maintaining fuel quality. Extensive oxidative degradation may
compromise quality by adversely affecting kinematic viscosity, acid value, or PV. This work examines the oil stability index
(OSI) as a parameter for monitoring the oxidative stability of soybean oil FAME (SME). SME samples from five separate sources
and with varying storage and handling histories were analyzed for OSI at 60°C using an oxidative stability instrument. Results
showed that OSI may be used to measure relative oxidative stability of SME samples as well as to differentiate between samples
from different producers. Although addition of α-tocopherol or TBHQ increased OSI, responses to these antioxidants varied
with respect to SME sample. Variations in response to added antioxidant were attributed to aging and other effects that may
have caused oxidative degradation in samples prior to acquisition for this study. Results showed that OSI was more sensitive
than iodine value in detecting the effects of oxidative degradation in its early stages when monitoring SME during storage. 相似文献
6.
Stavros?LalasEmail author Vassilis?Dourtoglou 《Journal of the American Oil Chemists' Society》2003,80(6):579-583
The effect of using a rosemary extract on the stability of oil used for frying potato chips has been evaluated. Sliced potatoes
were fried intermittently in soybean oil containing a natural extract from rosemary. The conditions used for frying were 185°C
for 90 s. Two separate experiments, with and without replenishment of oil, were carried out. Oil samples were taken each day,
not only from the frying pans but also by extraction with hexane from the chips. Changes in the induction period of the oil
samples (Rancimat method) were determined. The induction period decreased as frying progressed. The reduction in the induction
period was higher in the oil free of rosemary extract, and the chips were much darker in color. The oil containing the extract
showed greater antioxidant activity, and reduced darkening and rancidity of the oil. Potato chips fried in the oil with added
rosemary extract were more acceptable than chips fried in oil containing no extract until the last frying. The free radical
scavenging activity of rosemary extract in comparison to other natural antioxidants was also determined by the reduction of
O2
.- in a hypoxanthine/xanthine oxidase system. 相似文献
7.
Effect of natural antioxidants in virgin olive oil on oxidative stability of refined,bleached, and deodorized olive oil 总被引:1,自引:0,他引:1
M. Teresa Satue Shu-Wen Huang Edwin N. Frankel 《Journal of the American Oil Chemists' Society》1995,72(10):1131-1137
The factors influencing the oxidative stability of different commercial olive oils were evaluated. Comparisons were made of
(i) the oxidative stability of commercial olive oils with that of a refined, bleached, and deodorized (RBD) olive oil, and
(ii) the antioxidant activity of a mixture of phenolic compounds extracted from virgin olive oil with that of pure compounds
andα-tocopherol added to RBD olive oil. The progress of oxidation at 60°C was followed by measuring both the formation (peroxide
value, PV) and the decomposition (hexanal and volatiles) of hydroperoxides. The trends in antioxidant activity were different
according to whether PV or hexanal were measured. Although the virgin olive oils contained higher levels of phenolic compounds
than did the refined and RBD oils, their oxidative stability was significantly decreased by their high initial PV. Phenolic
compounds extracted from virgin olive oils increased the oxidative stability of RBD olive oil. On the basis of PV, the phenol
extract had the best antioxidant activity at 50 ppm, as gallic acid equivalents, but on the basis of hexanal formation, better
antioxidant activity was observed at 100 and 200 ppm.α-Tocopherol behaved as a prooxidant at high concentrations (>250 ppm) on the basis of PV, but was more effective than the
other antioxidants in inhibiting hexanal formation in RBD olive oil.o-Diphenols (caffeic acid) and, to a lesser extent, substitutedo-diphenols (ferulic and vanillic acids), showed better antioxidant activity than monophenols (p- ando-coumaric), based on both PV and hexanal formation. This study emphasizes the need to measure at least two oxidation parameters
to better evaluate antioxidants and the oxidative stability of olive oils. The antioxidant effectiveness of phenolic compounds
in virgin olive oils can be significantly diminished in oils if their initial PV are too high. 相似文献
8.
K.?WarnerEmail author J.?A.?Laszlo 《Journal of the American Oil Chemists' Society》2005,82(9):647-652
To determine antioxidative effects of ferulic acid and esterified ferulic acids, these compounds were added to soybean oils
(SBO), which were evaluated for oxidative stability and frying stability. Additives included feruloylated MAG and DAG (FMG/FDG),
ferulic acid, ethyl ferulate, and TBHQ. After frying tests with potato chips, oils were analyzed for retention of additives
and polar compounds. Chips were evaluated for hexanal and rancid odor. After 15 h frying, 71% of FMG/FDG was retained, whereas
55% of ethyl ferulate was retained. TBHQ and ferulic acid levels were 6% and <1%, respectively. Frying oils with ethyl ferulate
or TBHQ produced significantly less polar compounds than SBO with no additives. Chips fried in SBO with TBHQ or ferulic acid
had significantly lower amounts of hexanal and significantly less rancid odor after 8 d at 60°C than other samples. Oils were
also aged at 60°C, and stability was analyzed by PV, hexanal, and rancid odor. Oils with TBHQ or FMG/FDG had significantly
less peroxides and hexanal, and a lower rancid odor intensity than the control. FMG/FDG inhibited deterioration at 60°C, whereas
ethyl ferulate inhibited the formation of polar compounds in frying oil. Ferulic acid acted as an antioxidant in aged fried
food. TBHQ inhibited oil degradation at both temperatures.
Presented at the 94th AOCS Meeting & Expo, Kansas City, MO, May 4–7, 2003. 相似文献
9.
Hong-Sik Hwang Jill K. Winkler-Moser Brent Tisserat Rogers E. Harry-O'kuru Mark A. Berhow Sean X. Liu 《Journal of the American Oil Chemists' Society》2021,98(1):73-87
The food industry is seeking natural antioxidants for edible oils that have comparable activity to synthetic counterparts. In this study, Osage orange extract (OOE) rich in osajin (42.9%) and pomiferin (30.0%) was obtained after hexane extraction of the fruit, and its antioxidant activity was examined in stripped soybean oil (SBO) and fish oil (FO), in which antioxidants and polar compounds were removed. The antioxidant activity of OOE was compared with commercial natural antioxidants (i.e., rosemary extract and mixed tocopherols) and a synthetic antioxidant, butylated hydroxytoluene (BHT), during storage at 25 and 40 °C. The 0.1% OOE had stronger antioxidant activity than 0.1% rosemary extract and 0.1% mixed tocopherols in both oils at 25 and 40 °C. Its activity was similar to 0.02% BHT in SBO and was similar or slightly stronger than 0.02% BHT in FO. When OOE was studied at 0.05, 0.1, and 0.2%, there was a weak dose–response in SBO but a stronger dose–response in FO. Headspace volatile analysis using solid phase micro-extraction (SPME) combined with GC–MS indicated that 0.1% OOE was very effective in preventing the formation of volatile oxidation products in both oils. Although it should be further tested for safety before the actual use, this study shows that OOE can be developed as an antioxidant for edible oils. 相似文献
10.
Main objective of this work was to investigate the influence of pre-treatments of Satureja montana herbal material on supercritical extraction process, in terms: influence on extraction yield, composition and antioxidant activity of extracts. Four different pretreatments were investigated: water pre-treatment, ethanol pre-treatment, ultrasound and high pressure pre-treatment. Extraction yields were in the range from 1.68 to 2.35 g/100 g. Pre-treatments with water and ethanol increase the yield of extraction for 25% and 17%, respectively. According to GC/MS results the main compound of obtained extracts was carvacrol. Analyses confirmed that carvacrol content in extracts can be significantly increased by application of pre-treatments. Ultrasound pre-treatment and high pressure pre-treatment yielded highest concentration of carvacrol in extracts (around 66%). Using these two pre-treatments of herbal material, concentration of carvacrol, in extracts obtained by supercritical carbon dioxide extraction, could be increased for around 25%. Antioxidant activity of all extract was very high and in the range of well-known antioxidants. 相似文献