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In previous research, changes in concentrations of the physiologically essential elements K, Na, Ca, Mg, Fe, Mn, Zn, Cu and B in developing ovules of Clivia miniata Regel (central vacuole sap, endosperm tissue and embryo) were examined. Now the authors present results of measurements of change in molybdenum concentration in the central vacuole and micropylar and chalazal parts of endosperm during development of C. miniata ovules. The analysis was performed with the use of flameless atomic absorption spectrometry, with Zeeman background correction and using pyrolytically coated graphite tubes. The dimensions of the embryos and their age (counted from the day the perianth wilted to the day of sampling) were the adopted developmental criteria. It was established that (1) during the inhibitional phase of embryo growth, the concentration of Mo in the central vacuole sap varied from 0.021 to 0.052 µg/ml; (2) the Mo concentration in the micropylar part of the endosperm was in the range of 0.032-0.085 µg/g fr.wt. and increased during the exponential and stationary phases of embryo growth; (3) the same increasing tendency was found in the chalazal part of the endosperm tissue (concentration range: 0.074-0.11 µg/g fr.wt.); (4) the concentration of Mo in the chalazal part of the endosperm was higher than in the micropylar part during the examined period of embryo growth.
A field 2-factor split-plot experiment was carried out over 1998-2000 at the Pawłowice Agricultural Experiment Station. The aim of the experiment was to define the reaction of three bean cultivars ‘Longina’, ‘Małopolanka’ and ‘Mela’ cultivated for dry seeds on foliar fertilisation with boron and molybdenum and their mixture. The length of bean vegetation period depended on the cultivar and weather conditions. Over the three-year research the longest vegetation period was recorded for ‘Longina’ (121 days), and shorter – ‘Małopolanka’ (118 days) and ‘Mela’ (115 days). Morphological features, seed yield, content of organic components and crude ash in seeds were differentiated mostly by genetic factor and much less considerably by fertilisation with microelements.
This study was conducted on 25 animals randomly selected from a herd with 40 feedlot cattle, which had poor growth, rough hair coat, and change in the colour of the hair coat. Blood samples were collected from the vena jugularis into the tubes containing Na₂EDTA for the determination of plasma copper concentration and blood profile. Feed samples were also tested for copper, zinc, and molybdenum content. Ten healthy cattle were used as controls from different herds. In the affected group, mean plasma copper level was found to be at 6.43 µmol/L ± 0.01 and copper, molybdenum, and zinc levels in the diet were 15.55 ppm, 3.85 ppm, and 120 ppm, respectively. The mean plasma copper level in control animals was 13.50 µmol/L ±0.06). The difference was statistically significant (P<0.001). The deficiency of copper content may result from especially high molybdenum and zinc levels in the diet. When any finding indicative of this deficiency is observed in a herd, copper status of the animals should be determined. Then, copper and especially molybdenum and zinc concentration in the diet should be examined.
For approximately 100 years blesbok - endemic to South Africa - have been extinct in the wild and confined to fenced game reserves or farms. Biochemical-genetic variation was studied in blesbok from five isolated populations using electrophoretic allozyme analysis. Body weights and liver mineral concentrations were also determined. Material was collected from three localities in the Orange Free State province: a large reserve (PRE, ca 10 000 ha, N = 500-600, n = 23); a smaller reserve (KOP, ca 3 000 ha, N = 150-200, n = 14) with animals derived from the same source; and a farm (MID, ca 4 000 ha, N = up to 700, n = 19). The other two localities were a farm in the northern Cape Province (BEN, ca 10 000 ha, N = 200, n = 18) and another in the southern Cape Province (BRA, ca 150 ha, N = 50-80, n = 27), both with populations derived from small founder stocks. Three loci were polymorphic: Pgm-1, Acy-1, and Gpi-1 but Acy-1 was the only one polymorphic in all five populations. Pgm-1 was polymorphic in two populations derived from the same source and Gpi-1 in the other from the Orange Free State. Calculated over 45 presumptive structural loci the mean proportion of polymorphic loci (P) was 3.5% (SD = 1.2%), and mean expected average heterozygosity (He) was 0.9% (SD = 0.25%). The populations separated out by genetic distance in two distinct groups, those from the Cape Province and those from the Orange Free State. There were considerable differences in mean body weight between some sites. No correlation could be detected with level of heterozygosity. Body weight appeared rather to be related to liver mineral levels. In particular the ratio between copper and molybdenium appears important with those animals high in copper and low in molybdenium having a higher body weight.
Oznaczano molibden w suszu lucerny, ziarnie grochu, fasoli i soi oraz preparacie witaminowo-mineralnym Multi-tabs. Zastosowano metodę spektrofotometryczną wykorzystującą reakcję z 2,3,7-trihydroksyfenylofluoronem w obecności kationowego surfaktanta - bromku benzylododecylodimetyloamoniowego.
The study aimed at evaluating the influence of soil contamination with nickel on a background of varied liming on cadmium, molybdenum, and sodium contents in red clover biomass. The four-year pot experiment was carried out using a completely randomized pattern in which the following factors were examined: I – soil contamination with nickel (0, 50, 100, 150 mg Ni kg⁻¹ soil); II – liming (no liming or liming according to 0.5, 1.0, and 1.5 Hhsoil). Red clover (Trifolium pratense L.) as a test plant of which the seeds were sown every year, with its biomass harvested 4 times per each vegetation season. The content of Na, Cd and Mo was determined by the ICP-EAS technique. Study results were statistically processed by applying variance analysis, while LSD(0.05)values were calculated according to the Tukey test. In order to find dependencies between examined features, linear correlation analysis was performed as well. The soil contamination due to nickel up to 100 mg kg⁻¹ soil caused a decrease of Cd content with an increase at the highest contamination level of 150 mg kg⁻¹ soil, while decrease of Na and Mo concentrations at all applied nickel rates. Liming made average Na and Cd contents lower and mean Mo level higher in red clover biomass.
The authors present the effect of a mixture of microelements (boron, molybdenum, and manganese) as well as that of Florovit containing considerable amounts of microelements on the productivity of cultivars of green peas — Opal and Ramir — differentiated as to morphology and biology. Fertilization with a water solution applied at the beginning of appearance of flower buds. A favourable effect of the mixture of microelements and Florovit was ascertained on the yield of seeds and that of protein per unit of superficy as well as on the amino acid composition of the protein of seeds of the investigated cultivars of peas.
The content of the heavy metals cadmium, zinc, nickel, lead and molybdenum in products and waste coming from fuel processing (originating from power plants and coal mines) was determined using DPV. Samples were digested in a microwave mineralizer in mixtures of HNO3 + HClO4 acids (3:2; 4:2 v/v). The following certified reference materials were used in these investigations: fly ash (CTA-FFA-1), apatite concentrate (CTA-AC-1) and coal (BCR-40).
The heavy metals cadmium, nickel, lead, molybdenum and zinc were determined in 19 samples of moss taken from 19 points situated in the Gliwice and Sanok areas. Samples (segregated, cleaned and powdered) were digested by the wet method in the microwave mineralizer. Differential pulse anodic stripping voltam- metry (DPASV) was used for determination of Cd, Ni, Mo, Pb and Zn. Oriental tobacco (CTA-ATL-1) as the certified reference material was applied in those investigations.
In the years 2006–2007 radish ‘Opolanka’ cv. was grown in 60 × 40 × 20 cm containers, placed in the open field under a shade providing fabric. A loamy clay soil was used as a substrate. The following foliar nutrition treatments were applied twice: 1 – control (spray with water), 2 – urea, 3 – urea + Mo, 4 – urea + Mo + BA, 5 – urea + Mo + BA + sucrose, 6 – BA (benzyladenine) and 7 – sucrose. There were used the following concentrations of tested compounds: urea 20 g∙dm⁻³, sucrose 10 g∙dm⁻³, molybdenum (Mo) 1 mg∙dm⁻³ and BA 5 mg∙dm⁻³. Foliar nutrition treatments had a significant effect on average mass of plant leaves and on concentration of soluble sugars and ascorbic acid in radish roots. Plants treated with a mixture of urea + Mo + BA + sucrose featured the highest average mass of plant leaves. Radish roots of control plants and those sprayed solely with BA contained significantly more soluble sugars than roots of plants from other treatments. Spraying the plants with solutions containing only sucrose or only BA (treatments: 6 and 7) caused a significant reduction of ascorbic acid content in radish roots in comparison to other treatments. All the solutions used for foliar nutrition had no effect on radish roots mass and on mass of whole plants (roots + leaves). There were also not observed any significant changes in dry matter content of leaves and roots likewise in the content of phenolic compounds, phenylpropanoids, flavonols or anthocyanins in radish roots.
Concentrations of Cu, Zn, Mn, Mo and Co were determined in plant material from pot experiments including various plant species and cultivars of oat, broad beans, maize and spinach. Considerable species differences and smaller inter cultivars differences were detected in the concentration of trace elements. Diversified intensity of these elements translocation from roots to tops was observed both among species and cultivars.
The influence of various concentrations of salts of lead (II), copper (II), manganese (II), cobalt (II), molybdenum (IV) and iron (III) upon the soil dehydrogenase has been studied. Ecological areas featuring the contamination degree to which the studied soil environment had been exposed have been determined. Particular attention has been paid to high heavy metal doses causing significant disturbance to soil metabolism.
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