| Author (s): |
Lavinel G. Ionescu; clóvis Antônio Perazzolo
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| Title: |
LUIS FREDERICO LELOIR - SOUTH AMERICA S ONLY NOBEL PRIZE LAUREATE IN CHEMISTRY |
| Abstract: |
Luis Frederico Leloir, South America s only Nobel Laureate in Chemistry was born in Paris, France in 1906 and died in Buenos Aires, Argentina in 1987. He graduated as a physician from the University of Buenos Aires and was a student of Bernardo Houssay. With his own resouraes and help from his friends he founded in 1947 the Instituto de Investigaaiones Bioquimiaas (Fundaaion Campomar). He became famous for his research dealing with sugar nucleotides, biosynthesis of carbohydrates, and oxidation of fatty acids. He was awarded the Nobel Prize in Chemistry in 1970.
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| Keywords: |
Luis Frederico Leloir.
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| Year: |
1995
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| Initial page: |
1
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| Final page: |
8
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.4_1995.pdf |
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|
| Author (s): |
E. Esteve-Juan; R. Puchades; A. Maquieira
|
| Title: |
DETERMINATION OF ACETATE IN FOODS BY ION CHROMATOGRAPHY-FLOW INJECTION |
| Abstract: |
A method for acetate determination using IC separation and FI post-column spectrophotometric detection based on the La(OH)3-I2 reaction has been developed. The chromatographic conditions (eluants, flow-rates, sensitivity, and so on) and FI variables (length of coils, injection volume, pH, ... ) were optimized. Linearity was observed over the concentration range 0 to 1 gl-1 with HAc as standard (r = 0.9916) and a detection limit of 0.1 g AcH/l. The IC-FI method afforded a low relative standard deviation (3.6%) and was free from interferences. The IC-FI procedure was applied to the determination of acetate in mustard sauce and the results obtained agree with those provided by the reference method. Additionally, the developed method permits the simultaneous chromatographic analysis of other anions such as chloride, nitrate, phosphate, sulphate, and so on.
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| Keywords: |
acetate, flow-injection, ion chromatography, UV/V detection, foods.
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| Year: |
1995
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| Initial page: |
9
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| Final page: |
22
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.12_1995.pdf |
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|
| Author (s): |
Adriana Olmos da Rocha; Paulo Cesar Pereira das Neves
|
| Title: |
CHARACTERIZATION OF GEOCHEMICAL PARAMETERS OF AN ORGANIC SOIL FROM TERRA DE AREIA. NORTHERN COASTAL PLAIN. RIO GRANDE DO SUL. BRAZIL |
| Abstract: |
Sixteen samples of organic soil from a wetland, collected at a depth of 0.30 m, at a distance of 4 km from the town of Terra de Areia in the Northern Coastal Plain of Rio Grande do Sul, were analyzed and studied for the presence of various metals, nitrogen, phosphorus, organic carbon, sulfur, humidity, ashes, and heat content. The exact location of the sampling corresponds to Latitude 29°33 04 S; Longitude 50°03 25 W. On the basis of the experimental results obtained for organic carbon, ash, and heat content, it may be cone 1 used that the site is not a turfland. On the other hand, metal and flux analysis gave information about the evolution of the site and may be important from an ecological viewpoint.
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| Keywords: |
Turfland, Wetland, Soil Samples, Geochemical Analysis.
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| Year: |
1995
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| Initial page: |
23
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| Final page: |
36
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.26_1995.pdf |
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|
| Author (s): |
Dan Cascaval; Corneliu Oniscu; Adina Dumitrascu
|
| Title: |
MATHEMATICAL CORRELATION BETWEEN MASS TRANSFER COEFFICIENTS AND PARAMETERS INFLUENCING THE PENICILLIN G REACTIVE EXTRACTION PROCESS |
| Abstract: |
In this paper, a correlation between the individual mass transfer coefficient of Penicillin G for the aqueous phase and two parameters of the reactive extraction process of Penicillin G with Amberlite LA-2, namely the extractant concentration in the organic phase, and the mixing intensity, was established. The proposed correlation offers a good concordance with the experimental values of the mass transfer coefficient and may be applied with a maximum error of 18 % and an average deviation of 1. 6 %.
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| Keywords: |
Penicillin G extraction, reactive extraction, Amberlite LA-2, mass transfer coefficients..
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| Year: |
1995
|
| Initial page: |
37
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| Final page: |
53
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.40_1995.pdf |
|
|
| Author (s): |
Lourdes T. Kist; Bruno Szpoganicz; Manuel G. Basallote; Maria J. F. Trujillo; Maria A. Mariez
|
| Title: |
KINETICS OF OXIDATION WITH HYDROGEN PEROXIDE AND IRON(II) COMPLEX WITH A MACROCYCLIC BINUCLEATING LIGAND |
| Abstract: |
In the present study solutions of a complex of Fe(II) with a macrocyclic ligand were prepared and their oxidation kinetics with hydrogen peroxide examined. The kinetic studies of the oxidation processes lead to values of rate constant of two-step which occur via first-order kinetics. The results are expected to result in a better knowledge of the mechanism of H202 activation in catalyzed oxidation of organic substrates.
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| Keywords: |
iron(II), macrocyclic binucleanting, oxidation kinetics.
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| Year: |
1995
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| Initial page: |
55
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| Final page: |
62
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.57_1995.pdf |
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|
| Author (s): |
O. MAIOR; D. GAVRILIU; S. STOIA
|
| Title: |
SYNTHESES OF SOME PHENOXATHIIN DERIVATIVES WITH ANTIMICROBIAL ACTIVITY |
| Abstract: |
Antimicrobial activity has been studied on eighteen substances of phenoxathiin class (six of them being not yet described in the literature) evincing the fact that the oxidizing of the sulfur atom in position 10 leads to a severe decrease of the antibacterial activity.
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| Keywords: |
phenoxathiin, antimicrobial activity, sulfonium salts, O-methyl oximes.
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| Year: |
1995
|
| Initial page: |
79
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| Final page: |
88
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.65_1995.pdf |
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|
| Author (s): |
Paulo Irajara Borba Carneiro; Roberto Rittner
|
| Title: |
CARBON-13 NMR OF ALIPHATIC TERTIARY AMINES |
| Abstract: |
There are few data for the tertiary aliphatic amines in the literature. Unpublished Carbon-13 NMR data for seven aliphatic tetiary amines are reported and are inedited. The empirical substituent effects of the NMe2 and NEt2 groups were determined and can be useful in correlation analysis.
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| Keywords: |
Carbon-13 NMR, chemical shifts, aliphatic tertiary amines.
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| Year: |
1995
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| Initial page: |
89
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| Final page: |
92
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v3.n3.1995.75_1995.pdf |
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