| Author (s): |
A. D. Martinez; B. J. Kid
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| Title: |
A TRIBUTE TO PROFESSOR LAVINEL G. IONESCU ON HIS 55th BIRTHDAY |
| Abstract: |
Professor Lavinel G. Ionescu was born of Romanian parents in Varset (Vrsac), Banat, Yugoslavia, on May l9, 1943. He attended primary and secondary school in Yugoslavia, Italy, and Switzerland. He obtained the Bachelor of Science Degree in Chemistry in l963 and the Master of Science Degree in l966 from the University of New Mexico, Albuquerque, USA, and the Ph.D. Degree in Physical Chemistry from New Mexico State University, Las Cruces, USA in l970. He did postdoctoral work at the University of California, Santa Barbara, and has held faculty positions at universities in the United States and Brazil. At the present, he is Professor of Chemistry at the Pontifícia Universidade Catolica do Rio Grande do Sul, Porto Alegre and the Universidade Luterana do Brasil, Canoas, RS, Brazil. His research work includes liquid scintillators, radioactive isotopes, noble gases, solution thermodynamics, surfactants and micelles, micellar catalysis, respiratory pigments, membrane models, and history and philosophy of science. He has trained more than fifty research scientists from different parts of the world, is the author of more than two hundred and fifty scientific works, and has been the recipient of many prizes and awards.
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| Keywords: |
Lavinel, 55, birthday.
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| Year: |
1998
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| Initial page: |
1
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| Final page: |
10
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.4_1998.pdf |
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| Author (s): |
Elba Calesso Teixeira; Josete Dani Sanchez; Daniela Montanari Migliavacca
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| Title: |
EVALUATION OF AIR QUALITY IN A REGION OF COAL PROCESSING AND SIDERURGIC ACTIVITIES IN THE STATE OF RIO GRANDE DO SUL, BRAZIL |
| Abstract: |
The present work involved the determination of total suspended particles, SO2 e NO2 in the municipalities of Charqueadas and Sao Jeronimo, Rio Grande do Sul, Brasil. The area is marked by the presence of coal-fired power stations and siderurgic activities. The gases SO2 and NO2 do not affect air quality, but the results revealed contamination of air in Charqueadas due to total suspended particles. The presence of Fe, Mn, Cu, Cr, and Ni, is probably due to the steel industry. On the other hand, Pb and part of Cu and Ni can be attributed to the coal-fired power station.
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| Keywords: |
Air Quality, Sulfur Dioxide, Nitrogen Dioxide, Suspended Particles, Heavy Metals..
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| Year: |
1998
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| Initial page: |
11
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| Final page: |
23
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.14_1998.pdf |
|
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| Author (s): |
R. M. OLINESCU, MARIA GREABU, D. CROCNAN, F. A. KUMMEROW, VALY CONSTANTINESCU, FRAGA PAVELIU
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| Title: |
COMPARATIVE STUDY OF THE CHEMILUMINESCENCE PRODUCED BY THE ACTIVATED POLYMORPHONUCLEAR LEUKOCYTES IN PHYSIOLOGICAL AND VARIOUS PATHOLOGICAL CONDITIONS |
| Abstract: |
The chemiluminescent emission released by activated polymorphonuclear leukocytes has been known for a long time, but its clinical use is still scarce. We suggest the as a quantitative measurement of chemiluminescence, the stimulatmy index (ratio of the chemiluminescence value of stimulated polymorphonuclear leukocytes to non-stimulated leukocytes) was obtained for the same individual. The results obtained by a standardized, simplified technique for more than 2000 individuals (healthy persons such as medical personnel, athletes, soldier, and patients suffering from cardiovascular disease, cancer, and pneumoconiosis) explain the still restricted use of chemiluminescence. There was a wide range of individual variations and an overlap of normal physiological and pathological values. A significant statistical difference was obtained only for patients in the acute phase of the disease. The chemiluminescence measurement of phagocytic activity of leukocytes is strongly influenced by age, diet, presence of stress, and chronic inflammations.
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| Keywords: |
chemiluminescence, phagocytosis, leukocytes..
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| Year: |
1998
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| Initial page: |
25
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| Final page: |
32
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.27_1998.pdf |
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| Author (s): |
T. Gavriloaiei, Raluca Mocanu, Maria Calistru, R. Olariu
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| Title: |
COMPARATIVE STUDY OF BIOSORPTION OF METALLIC CATIONS BY DIFFERENT BACTERIA |
| Abstract: |
Certain species of microorganisms have been found to accumulate surprisingly large quantities of important metals, involved in the toxicity provoked by human activities (Cd, Pb, Hg) and metals of economic values (Ag, Au). Microbiological methods are applied to large-scale recovery or removal of metallic ions from aqueous solutions. These applications involved the removal of heavy metals from sewage sludge, industrial effluents, and mine or wastewaters. This process has been developed using immobilized extracellular or cellular ligands or more simple chemical models based upon them. The uptake of metal ions on the cell surface and their translocations into the cell are well-known natural processes. These adsorption processes could be expressed using Langmuir isotherms. Fe2+ and Mn2+ appeared to .be the most effective cations for adsorption by Bacillus subtilis, Pseudomonas aeruginosa, even by Saccharomyces cerevisiae, while the Zn2+ cation, in spite of a great value of maximum adsorption, has a toxic action on microorganisms and the 'detoxification" mechanism depends on genetic control.
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| Keywords: |
bioadsorption, bioaccumulation, bacterial .species, Langmuir isotherm.
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| Year: |
1998
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| Initial page: |
33
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| Final page: |
44
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.35_1998.pdf |
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| Author (s): |
Vania Regina Gabbi Polli; Alnei Ramos Prochnow; Juliane Zimmernan Tamanini
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| Title: |
EXTRACTION OF COLORED SUBSTANCES FROM MATE (ILEX PARAGUARIENSIS) |
| Abstract: |
Liquid-liquid extraction of pigments present in mate (flex Paraguariensis) was studied using various organic solvents and different concentrations. The best results were obtained using diethyl ether and sodium lauryl sulfate. The effect of the addition of ethanol on the extraction process was also analyzed.
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| Keywords: |
Mate (Ilex Paraguariensis), liquid-liquid extraction, saponins, sodium !amyl sulfate, pigments. .
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| Year: |
1998
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| Initial page: |
45
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| Final page: |
51
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.47_1998.pdf |
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| Author (s): |
Anca Emandi; Mariana Balasoiu; Tudor Rosu
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| Title: |
New Complexes of Pr(III), Sm(III), Gd(lll), Gd(III), La(III) 1-(2-Benzthyazolyl)-3-methyl-4-azo-(4-nitrophenyl)-Pyrazolyn-5-one |
| Abstract: |
1-(2-Benzthyazolyl)-3-methyl-4-azo-(4-nitrophenyl)-Pyrazolyn-5-one (HL) possesses a chelating behavior. Its chelates with a number of trivalent lanthanide ions Pr(III), Sm(III),Gd(III), Ho(III), La(III) of the type Na3[Ln(L)2(OH)4] have been isolated and characterized on the basis of their elemental analyses, IR and visible spectra, magnetic and molar conductance studies, thermal and X-ray analysis and molecular weight determinations. All chelates have a monomeric octa-coordinated stn1cture and square antiprismatic (C2) symmetry.
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| Keywords: |
Lanthanides complexes; Azodye; Pyrazolyn-5-one; UV-VIS; IR spectroscopy.
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| Year: |
1998
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| Initial page: |
53
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| Final page: |
62
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.55_1998.pdf |
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| Author (s): |
RODICA GALASIU; IOAN GALASIU; NICULAE POPA; VASILICA CHIVU
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| Title: |
SnO2 -BASED INERT ANODES FOR ALUMINIUM ELECTROLYSIS. THE INFLUENCE OF CeO2 ADDITION ON THE ELECTRICAL RESISTIVITY |
| Abstract: |
Five recipes of SnO2 - based ceramics masses were prepared. The influence of CeO2 additions on the properties of ceramic masses were studied. It was found that the CeO2 additions increase the electrical resistivity of these ceramic masses, but the electrical resistivity decreases with the CeO2 content. The CeO2 additions have the same influence on the activation energy for conductivity.
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| Keywords: |
Inert anodes; aluminium electrolysis.
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| Year: |
1998
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| Initial page: |
63
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| Final page: |
69
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.65_1998.pdf |
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| Author (s): |
S. JIPA, R. SETNESCU, T. SETNESCU, C.PODINA, J. MIHALCEA
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| Title: |
EFFECTIVENESS OF CERTAIN STABILIZERS ON THE AGEING OF POLYETHYLENE FILMS |
| Abstract: |
The effectiveness of different phenolic antioxidants on high-density polyethylene (HDPE) and low-density polyethylene (LDPE) has been studied by the Isothermal chemiluminescence method. The decreasing order of the antioxidant efficiency for these polymers Is as follows: lrganox 1010 >> Etanox 330 > lrganox 1076 (Hostanox 016) > Topanol OC
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| Keywords: |
polyethylene, thermal-oxldative destruction, antioxidants, chemiluminescence.
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| Year: |
1998
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| Initial page: |
71
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| Final page: |
76
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.80_1998.pdf |
|
|
| Author (s): |
Lia Stanciu, Melania-Liliana Arsene, Constanta Parlog
|
| Title: |
IMMOBILIZATION OF ALCOHOL OXIDASE IN SiO2 MATRIX PREPARED BY SOL-GEL METHOD |
| Abstract: |
The possibility of obtaining a biochemical sensor for colorimetric determination was studied for this purpose, we have used the redox indicator 2.6-dichlorophenolindophenol (DCIP) and the binary enzymatic system composed by alcohol oxidase (AO) and peroxidase (PER). The binary enzymatic system immobilized in an inert SiO2 matrix was obtained by modfied sol-gel process. The chromogen and binary enzymatic system immobilization into a SiO2 matrix was confirmed by I.R. spectroscopy. By immobilization of the enzymatic system, both the stability and enzymatic activity increase.
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| Keywords: |
sol-gel, immobilization, enzymes, alcohol oxidase, 2,6-dichlorophenolindophenol.
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| Year: |
1998
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| Initial page: |
77
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| Final page: |
86
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| Link: |
Acessar |
| DOI: |
10.48141/SBJCHEM.v6.n6.1998.86_1998.pdf |
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