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1.
J Hazard Mater ; 151(2-3): 710-9, 2008 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-17643816

RESUMO

Three materials were prepared from paper sludge (PS) using different treatment processes and their sorption abilities for phosphate and methylene blue (MB) were determined. The samples were a powder sample prepared by heating PS in air (sample C), a pellet prepared by grinding, forming and heating PS in air (sample G) and a powder prepared by physical activation of PS in flowing wet nitrogen (sample A). The three samples were heated at 600-900 degrees C for 6h. On heating at 700-800 degrees C, the organic fibers, limestone (CaCO3), kaolinite (Al2Si2O5(OH)4) and talc (Mg3Si4O10(OH)2) in the original PS were converted to amorphous CaO-Al2O3-SiO2 (CAS) and talc in sample C, while CAS was formed in sample G and activated carbon, CAS and talc was formed in sample A. On heating at 900 degrees C the CAS converted to gehlenite (Ca2Al2SiO7) and anorthite (CaAl2Si2O8). The specific surface areas (SBET) of the three samples achieved maximum values of 23, 37 and 70 m2/g upon heating at 700, 600 and 600 degrees C, respectively. The SBET value of the activated sample A was distinctly lower than usually reported for activated carbon. The samples C, G and A achieved maximum phosphate sorption capacities of 2.04, 1.38 and 1.70 mmol/g, calculated from the Langmuir model, upon heating at 700, 700 and 800 degrees C, respectively. The maximum sorption capacity for phosphate in sample C is attributed to the sorption by CAS, namely, adsorption on the alumina component and precipitation as Ca-phosphates. The MB multifunctional sorption capacity of sample A was 0.11 mmol/g. The phosphate and MB sorption rates show better correlation with a pseudo-second order model than with other models.


Assuntos
Papel , Esgotos , Adsorção , Carbonato de Cálcio/análise , Técnicas de Química Analítica/métodos , Físico-Química/métodos , Íons , Caulim/análise , Azul de Metileno/química , Microscopia Eletrônica de Varredura , Fosfatos/química , Pós , Estresse Mecânico , Talco/análise , Temperatura
2.
J Hazard Mater ; 137(1): 352-8, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16530942

RESUMO

Porous materials consisting of activated carbon and amorphous CaO-Al(2)O(3)-SiO(2) (CAS) compound were prepared from refuse paper and plastic fuel (RPF), (a mixture of old paper and plastic) by carbonizing and/or activating treatments. Samples formed by chemical activation using K(2)CO(3) showed a high specific surface area (S(BET)) of 1330 m(2)/g but a lower ash content due to being washed after activation. By contrast, samples prepared by physical activation using steam showed rather lower S(BET) (510 m(2)/g) due to higher ash contents. The physically activated samples showed much higher uptake properties for Ni(2+) (a representative heavy metal) and phosphate ions (a representative of a harmful oxyanion) than the chemically activated samples because of the higher content of amorphous CAS in the former samples. By contrast, the chemically activated samples showed higher uptake for methylene blue (MB, a representative organic material) than the physically activated samples because of the higher activated carbon content of higher surface area. Although differences in the sorption properties for Ni(2+), phosphate ion and MB were found between the physically and chemically activated samples, both samples show excellent multiple sorption properties for cation-anion combinations and inorganic-organic sorbents.


Assuntos
Plásticos/química , Porosidade , Eliminação de Resíduos/métodos , Eliminação de Resíduos Líquidos/métodos , Adesivos , Adsorção , Ânions , Cátions , Resíduos de Alimentos , Resíduos Industriais , Azul de Metileno/química , Níquel/química , Papel , Eliminação de Resíduos/instrumentação , Eliminação de Resíduos Líquidos/instrumentação , Resíduos , Purificação da Água
3.
Plant Dis ; 85(10): 1122, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30823299

RESUMO

A preliminary survey to identify virus diseases affecting wheat in Uzbekistan was conducted during May 2001. The survey covered 12 wheat fields from 2 cereal-growing regions (Tashkent-Angren and Tashkent-Samarkand). A total of 250 wheat samples with symptoms suggestive of virus infection were collected and tested for the presence of nine viruses by tissue-blot immunoassay (TBIA) (1) at the Virology Laboratory of ICARDA, Aleppo, Syria, using the following antisera: monoclonal antibodies for Cereal yellow dwarf virus-RPV (CYDV-RPV) (ATCC PVAS-669 [American Type Culture Collection, Manassas, VA]) and Barley yellow dwarf virus-MAV (BYDV-MAV) (ATCC PVAS-673); and polyclonal antibodies for BYDV-SGV and BYDV-RMV (3); BYDV-PAV, Barley stripe mosaic virus, and Wheat streak mosaic virus (from Virology Laboratory, ICARDA); Wheat dwarf virus (provided by J. Vacke, Research Institute of Crop Production, Prague, Czeck Republic); and Barley yellow striate mosaic virus (BYSMV) isolated from Lebanon (2). The most common virus present was BYDV-PAV (detected in 12% of the 250 samples tested), followed by BYDV-SGV (10.8%), BYSMV (5.6%), BYDV-RMV (2.4%), BYDV-MAV (2%), and CYDV-RPV (1.2%). CYDV-RPV was detected in three fields; one field was 50 km southeast of Tashkent, and the other two fields were between Tashkent and Samarkand. The majority of BYSMV-positive samples originated from the same field, ≈40 km northeast of Samarkand. Field symptoms of BYSMV-infected plants included yellow flag leaf and stunting. All samples that produced a positive reaction to BYSMV-Lebanon antiserum were tested against four other rhabdovirus antisera: BYSMV-Italy, BYSMV-Morocco, Cereal chlorotic mottle virus, and American wheat striate mosaic virus. Serological tests showed that 100% of the samples reacted strongly with BYSMV-Italy and BYSMV-Morocco. In sodium dodecyl sulfate-polyacrylamide gel electrophoresis, followed by western blots, extracts from BYSMV-infected plants were found to contain 66- and 47-kDa structural proteins, typical of G and N proteins of rhabdoviruses, both of which reacted strongly with BYSMV-Italy antiserum. To our knowledge, this is the first report of BYSMV and CYDV-RPV in Uzbekistan. References: (1) K. M. Makkouk and A. Comeau. Eur. J. Plant Pathol. 100:71, 1994. (2) K. M. Makkouk et al. Plant Dis. 85:446, 2001. (3) G. N. Webby and R. M. Lister. Plant Dis. 76:1125, 1992.

4.
Vopr Med Khim ; 40(2): 48-52, 1994.
Artigo em Russo | MEDLINE | ID: mdl-8160432

RESUMO

Content of phospholipids as well as activity of phospholipase A2 and lysophospholipase A1 were studied in the hepatic mitochondrial membranes of rats exposed to high temperatures. A decrease in the content of phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and increase in fractions of cardiolipin, phosphatidylserine, phosphatidic acid and lysophospholipids were detected in liver tissue mitochondria after heat stress. Alterations of phospholipid levels in the mitochondrial membranes correlated with the rate (36-37 degrees and 41-43 degrees) and duration (2 and 4 hrs) of heat exposure. Under mild conditions of heat exposure, phospholipase A2 and lysophospholipase A1 were activated in rat liver mitochondrial membranes. With elongation of the heat effect up to 4 hr activation of the lipolytic enzymes was increased. Under most severe conditions of heat stress, a marked activation of phospholipase A2 was observed, while the activity of lysophospholipase A1 was decreased and approached to control values.


Assuntos
Temperatura Alta/efeitos adversos , Lipídeos de Membrana/metabolismo , Mitocôndrias Hepáticas/metabolismo , Fosfolipídeos/metabolismo , Estresse Fisiológico/metabolismo , Animais , Membranas Intracelulares/enzimologia , Membranas Intracelulares/metabolismo , Lipólise , Masculino , Mitocôndrias Hepáticas/enzimologia , Fosfolipases A/metabolismo , Fosfolipases A2 , Ratos
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