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51.
Fathi Habashi Farouk T. Awadalla 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1986,36(1):1-6
When phosphate rock is dissolved in nitric acid, phosphoric acid and uranium can be selectively extracted by tertiary amyl alcohol; other impurities including the lanthanides remain in the aqueous phase. Uranium can be recovered from the alcohol phase by selective stripping and the lanthanides from the raffinate by extraction with tributyl phosphate. 相似文献
52.
In the present work, we report the effects of C(60)-pretreatments on acute carbon tetrachloride intoxication in rats, a classical model for studying free-radical-mediated liver injury. Our results show that aqueous C(60) suspensions prepared without using any polar organic solvent not only have no acute or subacute toxicity in rodents but they also protect their livers in a dose-dependent manner against free-radical damage. To be sure, according to histopathological examinations and biological tests, pristine C(60) can be considered as a powerful liver-protective agent. 相似文献
53.
The electroreduction of a series of 3-phenyl-2,3-dioxopropionanilide 2-arylhydrazones (III) on the dropping mercury electrode (dme) was investigated in ethanolic Britton-Robinson buffers. In each case, the polarographic curves showed two waves, A and B, corresponding to a four- and a two-electron process, respectively. The E1/2 values for the wave A at pH 8.0 were shown to be a linear function of the Hammett substituent constant σ; -(E1/2)A(V) = 0.982 + 0.145 σ (r = 0.989). A mechanism for the polarographic reduction of III is proposed. 相似文献
54.
55.
Zereini F Alt F Messerschmidt J von Bohlen A Liebl K Püttmann W 《Environmental science & technology》2004,38(6):1686-1692
The concentrations and distribution of platinum group elements (Pt, Pd, Rh) in airborne particulate matter were studied in a period of one year from August 2001 to July 2002 in urban and in nonurban areas. Airborne dust samples were collected as a total amount (particles with an aerodynamic diameter <22 microm) and classified using an eight-stage Andersen impactor (<10 microm) at three locations with different traffic density roads in the Frankfurt am Main and nonurban areas. Sampling at the three locations was performed simultaneously for total airborne dust and fractionated airborne dust. Pd was determined by total reflection X-ray fluorescence after Hg coprecipitation. Pt and Rh were analyzed by adsorptive striping voltammetry after HPA digestion. The results show that the PGE concentrations in airborne samples depend on the traffic density. The highest PGE concentrations in air were found in the vicinity of major roads with heavy traffic, and the lowest ones were found in the nonurban area. The presence of PGE at the sampling station relatively free of traffic in a nonurban area hints to a transport of some of the emitted PGE from the city to this station by wind. At all three sampling locations, a heterogeneous distribution of the Pd, Pt, and Rh concentrations during the sampling year can be observed. The sum of PGE concentrations in total airborne dust is comparable with the sum of impactor samples. However, the concentration of Pt and Rh in total airborne dust (<22 microm) is on average higher than in impactor samples (<10 microm). On the contrary, Pd concentration is higher in impactor samples in most cases. The airborne PGE distribution is dominated by Pt, followed by Pd and Rh. The impactor samples are dominated by Pd, followed by Pt and Rh. This fact indicates that palladium occurs mainly in relatively fine airborne particles. The main fraction of PGE is found on average in particle sizes between 1.1 and 4.7 microm. Knowledge of the size distribution of particles containing PGE is important with respect to risk assessment of human inhalation. 相似文献
56.
Zohreh Khezri Hajar Shekarchizadeh Milad Fathi 《International Journal of Food Science & Technology》2021,56(5):2255-2263
Opopanax gum/gelatin nanofibre was produced by the electrospinning method, and the efficiency of this new technique for encapsulation of garlic essential oil was investigated. Fourier-transform infrared spectroscopy results showed the physical and weak interactions between opopanax gum and gelatin, as well as the improvement of their thermal stability in the nanofibres structure. Incorporating 10% garlic essential oil based on biopolymer weight in nanofibres was considered the best percentage. The results confirmed the presence of garlic essential oil in the nanofibres and the improvement of its thermal stability by entrapment to the nanofibre structure. The data of analysis of the stability of garlic essential oil in the forms of free and encapsulated conditions showed that its stability increased at 25 °C from 20 days to more than 60 days. It indicated the efficiency of opopanax gum/gelatin nanofibres as an applicable coating material for stability enhancement of essential oils. 相似文献
57.
58.
Aicha O. Cherif Nathalie Leveque Mhamed Ben Messaouda Habib Kallel Alain Tchapla Fathi Moussa 《LWT》2014
A simple strategy to identify triacylglycerols (TAGs) in wild and cultivar peanuts was performed using on line coupling of non-aqueous reversed phase chromatography-electrospray ionization–mass spectrometry (NARP-LC-ESI–MS) with silver nitrate (AgNO3) as a post-column additive. The combination of the structural information given by MS with chromatographic retention laws led to the determination of the structure of TAGs in wild and cultivar peanut oil. In addition, by using the MS5 method, the regio-specificity of the TAGs was determined. It was also demonstrated that in Tunisian peanut oil, the saturates have a preference for the sn-1/sn-3 position for the arachidonic and behenic acids. In the wild variety fatty acids with odd numbers of carbons were found and more TAGs were identified in comparison to the cultivar peanut oil. 相似文献
59.
Modaresi J Fathi Nasri MH Rashidi L Dayani O Kebreab E 《Journal of dairy science》2011,94(8):4075-4080
The effects of feeding pomegranate seed pulp (PSP) on milk yield, milk composition, fatty acid profiles of milk fat, and blood metabolites were examined in this study. During a pretrial period, 27 multiparous southern Khorasan (Iran) cross-bred goats were fed a similar diet and dry matter intake, milk yield, and milk composition were recorded. After adaptation and based on pretrial records, the goats were randomly assigned to 1 of 3 experimental diets and were housed in individual stalls. Experimental diets included 0, 6, or 12% of PSP (dry matter basis) and were fed as total mixed rations ad libitum for a 45-d period. Diets were formulated to be isonitrogenous and isocaloric. Supplementation of PSP did not affect dry matter intake or average daily gain of goats. Milk yield was not affected by inclusion of PSP in the diet. Milk fat concentration of goats fed diets with 6 and 12% PSP increased, but milk fat yield, milk protein concentration, and milk solids-not-fat concentration of goats were not affected by diets. Feeding PSP did not affect blood glucose, cholesterol, urea N, triglyceride, or lipoproteins. Feeding goats a diet containing 12% PSP modified the milk fatty acid profile, including conjugated linoleic, punicic, and vaccenic acids. 相似文献
60.
Treatment of meat with gamma radiation for inactivation of foodborne pathogens might cause undesirable quality changes in the product. The objective of the present study was to use nisin for enhancing the lethality of gamma radiation against Listeria monocytogenes, so that moderate doses of radiation can effectively eliminate the pathogen on meat. Cubes of raw meat (10 g each) were inoculated with L. monocytogenes (10(7)CFU/g) and treated with nisin (10(3) IU/g), gamma radiation (0.25 to 1.5 kGy), or combinations of these treatments. Meat was analyzed for L. monocytogenes survivors immediately after treatment and during storage at 4 °C for up to 72 h. Nisin treatment alone inactivated L. monocytogenes by 1.2 log CFU/g. Gamma radiation caused dose-dependent inactivation of the pathogen. Treatment with combinations of nisin and gamma radiation resulted in an additive antimicrobial effect when inoculated meat was tested during the first 24 h and in a synergistic effect when tested after 72 h of storage at 4 °C. When L. monocytogenes was inoculated onto meat at low levels (4×10(3) CFU/g), treated with nisin (10(3) IU/g), and then irradiated (1.5 kGy) and stored at 4 °C for 72 h, the pathogen's most probable number was <0.03/g, indicating that such a combination is potentially effective in eliminating L. monocytogenes in meat. 相似文献