20 resultados para Nitrate recirculation
em Brock University, Canada
Resumo:
Soybean (Glycine ~ (L.) Merr. cv. Harosoy 63) plants inoculated with Rhizobium japonicum were grown in vermiculite in the presence or absence of nitrate fertilization for up to 6 weeks after planting. Overall growth of nodulated plants was enhanced in the presence of nitrate fertilization, while the extent of nodule development was reduced. Although the number of nodules was not affected by nitrate fertilization when plants were grown at a light intensity limiting for photosynthesis, at light intensities approaching or exceeding the light saturation point for photosynthesis, nitrate fertilization resulted in at least a 30% reduction in nodule numbers. The mature, first trifoliate leaf of 21 day old plants was allowed to photoassimi1ate 14C02. One hour after·· the initial exposure to 14C02, the , plants were harvested and the 14C radioactivity was determined in the 80% ethanol-soluble fraction: in. o:rider to assess· "the extent of photoassimilate export and the pattern of distribution of exported 14C. The magnitude of 14C export was not affected by the presence of nitrate fertilization. However, there was a significant effect on the distribution pattern, particularly with regard to the partitioning of 14C-photosynthate between the nodules and the root tissue. In the presence of nitrate fertilization, less than 6% of the exported 14C photosynthate was recovered from the nodules, with much larger amounts (approximately 37%) being recovered from the root tissue. In the absence of nitrate fertilization, recovery of exported 14C-photosynthate from the nodules (19 to 27%) was approximately equal to that from the root tissue (24 to 33%). By initiating- or terminating the applications of nitrate at 14 days of age, it was determined that the period from day 14 to day 21 after planting was particularly significant for the development of nodules initiated earlier. Addition of nitrate fertilization at this time inhibited further nodule development while stimulating plant growth, whereas removal of nitrate fertilization stimulated nodule development. The results obtained are consistent with the hypothesis that nodule development is inhibited by nitrate fertilization through a reduction in the availability of photosynthate to the nodules.
Resumo:
The crystal structure of Cu(PM)2(N03hoH20 (where PM is pyridoxamine, CSHI2N202) has been determined from three dimensional x-ray diffraction data. The crystals are triclinic, space group pI, a = 14.248 (2), b = 8.568 (1), c = 9.319 (1) 1, a = 94.08 (1), e = 89.73 (1), y~~ 99.18 (1)°, z = 2, jl(MoK) = 10.90 em-I, Po = 1.61 g/cm3 and Pc = 1.61 g/em3• The structure a was solved by Patterson techniques from data collected on a Picker 4-circle diffractometer to 26max = 45°. All atoms, including hydrogens, have been located. Anisotropic thermal parameters have been refined for all nonhydrogen atoms. For the 2390 independent reflections with F ? 3cr(F) , R = 0.0408. The results presented here provide the first detailed structural information of a metal complex with PM itself. The copper atoms are located on centres of symmetry and each is chela ted by two PM zwitterions through the amino groups and phenolate oxygen atoms. The zwitterionic form found in this structure involves the loss of a proton from the phenolate group and protonation of the pyridine ring nitrogen atoms. The two independent Cu(PM)2 moieties are symmetrically bridged by a single oxygen atom from one of the nitrate groups. The second nitrate group is not coordinated to the copper atoms but is central to an extensive hydrogen bonding network involving the water molecule and uncoordinated functional groups of PM.
Resumo:
Some Ecological Factors Affecting the Input and Population Levels of Total and Faecal Coliforms and Salmonella in Twelve Mile Creek, Lake Ontario and Sewage Waters Near St. Catharines, Ontario. Supervisor: Dr. M. Helder. The present study was undertaken to investigate the role of some ecological factors on sewage-Dorne bacteria in waters near St. Catharines, Ontario. Total and faecal coliform levels and the presence of Salmonella were monitored for a period of a year along with determination of temperature, pH, dissolved oxygen, total dissolved solids, nitrate N, total phosphate P and ammonium N. Bacteriological tests for coliform analysis were done according to APHA Standard Methods by the membrane filtration technique. The grab sampling technique was employed for all sampling. Four sample sites were chosen in the Port Dalhousie beach area to determine what bacteriological or physical relationship the sites had to each other. The sample sites chosen were the sewage inflow to and the effluent from the St. Catharines (Port Dalhousie) Pollution Control Plant, Twelve Mile Creek below the sewage outfall and Lake Ontario at the Lakeside Park beach. The sewage outfall was located in Twelve Mile Creek, approximately 80 meters from the creek junction with the beach and piers on Lake Ontario. Twelve Mile Creek normally carried a large volume of water from the WeIland Canal which was diverted through the DeCew Generating Station located on the Niagara Escarpment. An additional sample site, which was thought to be free of industrial wastes, was chosen at Twenty Mile Creek, also in the Niagara Region of Ontarioo 3 There were marked variations in bacterial numbers at each site and between each site, but trends to lower_numbers were noted from the sewage inflow to Lake Ontario. Better correlations were noted between total and faecal coliform population levels and total phosphate P and ammonium N in Twenty Mile Creek. Other correlations were observed for other sample stations, however, these results also appeared to be random in nature. Salmonella isolations occurred more frequently during the winter and spring months when water temperatures were minimal at all sample stations except the sewage inflow. The frequency of Salmonella isolations appeared to be related to increased levels of total and faecal coli forms in the sewage effluent. However, no clear relationships were established in the other sample stations. Due to the presence of Salmonella and high levels of total and faecal coliform indicator organisms, the sanitary quality of Lake Ontario and Twelve Mile Creek at the sample sites seemed to be impaired over the major portion of the study period.
Resumo:
A small tintype of a young Black woman dressed in white. The date, location and name of the photographer are unknown. This tintype was among the family memorabilia belonging to Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Sloman - Bell family are descended from former American slaves."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
A small tintype of three unidentified individuals, two women, seated, and a young Black gentleman, standing. The date, location and name of the photographer are unknown. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have relatives who were former American slaves who came to Canada. They later settled in the London and St. Catharines areas of Ontario."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
An unidentified man poses for his portrait seated on a stool in this undated black and white tintype photograph. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Bell - Sloman family include former Black slaves from the United States who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
This small black and white tintype photograph shows a young Black gentleman smoking a cigar. No date or location is provided. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Sloman - Bell families are descended from former slaves from the United States who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
Black and white tintype of an unidentified woman seated with hand-colored red detail on her scarf and the tablecloth. The date, location and photographer are unknown. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Bell - Sloman families include former slaves from the United States who escaped to Canada. They later settled in the London and St. Catharines areas of southern Ontario."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
An unidentified couple is pictured in this early black and white tintype photograph. The date, location and name of the photographer are unknown. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Bell - Sloman families have relatives who are descended from African American slaves who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
This unhappy looking young girl is featured in an early black and white tintype photograph. The date, location and name of the photographer are unknown. This small tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have descendants who are former slaves from the United States."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
A young woman seated with arm resting on a side table is pictured in this small black and white tintype photograph. The date, location and name of the photographer are unknown. This tintype was among the family memorabilia in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have relatives who were former slaves from the United States. They escaped to Canada and later settled in the London and St. Catharines areas of Ontario."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
A young African American girl peers through a lattice window in an unknown photographer's studio in this small black and white tintype. The girl in the photo is unidentified. There are slight scratches on the surface of the tintype, which is cut in a hexagonal shape. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have relatives who are descended from Black slaves from the United States."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
An unidentified African American man poses beside a wooden fence in the studio of an unknown photographer in this small black and white tintype photograph. A painted landscape serves as the backdrop. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families are descended from former American slaves who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
A woman standing with a book beside a table covered with a decorative cloth is featured in this small black and white tintype photograph. The tintype has been mounted in a paper slip frame with gold edging. There is a small area of red, hand-colored highlighting on the tablecloth. The backdrop appears to be a painted landscape scene. The tintype is undated and there is no indication of the identity of the woman in the photo or the photographer. This tintype was in the possession of Iris Sloman Bell, of St. Catharines, Ontario. The Sloman - Bell families have relatives who are former slaves from the United States who later settled in southern Ontario."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html
Resumo:
Three unidentified Black women, two seated and one standing, pose against a painted backdrop in the studio of an unknown photographer. This small black and white tintype has been cut on the upper and lower left-hand corners. The back of the tintype is a copper color. This photograph was among the family memorabilia in the possession of Iris Sloman Bell, of St. Catharines, Ontario. Relatives of the Sloman - Bell families include former American slaves who settled in Canada."Tintypes were the invention of Prof. Hamilton Smith of Ohio. They begin as thin sheets of iron, covered with a layer of black paint. This serves as the base for the same iodized collodion coating and silver nitrate bath used in the ambrotype process. First made in 1856, millions were produced well into the twentieth century. When tintypes were finished in the same sorts of mats and cases used for ambrotypes, it can be almost impossible to distinguish which process was used without removing the image to examine the substrate." Source: American Museum of Photography http://www.photographymuseum.com/primer.html