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Twenty-eight warmblood mares were monitored during their late pregnancy in the Teaching Hospital of Ghent University. The reliability of two commercial assays (enzyme immunoassay and glutaraldehyde coagulation test) used for determining the IgG concentrations of their newborn foals was tested. Mammary secretions were examined at the time of foaling (T0), and then 4 (T1) and 8 (T2) hours after foaling by refractometry and electrophoresis. The foals’ blood IgG levels were measured at T1 and T2 as a routine clinical diagnostic examination using two different commercial test kits (SNAP Foal Ig and Gamma-Check E) and T0, T1 and T2 samples were stored (at −18 °C) for immunoglobulin (Ig) determination by electrophoresis. Differences between the results of refractometry and electrophoresis occurred in 27.8% of the colostrum analyses. Some serum IgG could be detected immediately post partum (T0) in 75% of the foals, and 42.82% of the newborn foals acquired a serum concentration of more than 800 mg/dl IgG within 8 h of birth. Compared to the electrophoresis, the glutaraldehyde test scored better (85%) than the enzyme immunoassay (74%), although both are accurate and safe to use since they clearly distinguish between safe and unsafe IgG concentrations.

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Abstract  

A number of experimental techniques are employed to characterize physical and thermal properties of poly(lactic acid), PLA. To characterize PLA in terms of molecular mass and molecular mass distribution, size exclusion chromatography was used. The value of the specific refractive index increment was measured by differential refractometry. The thermal properties of semicrystalline PLA were measured by standard and temperature-modulated differential scanning calorimetry. The thermal stability of PLA was monitored by measuring the changes of mass using thermogravimetric analysis. The mechanical properties of amorphous PLA were measured by dynamic mechanical analysis and the results were discussed and compared with DSC in the glass transition region.

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Abstract

In the case of fruit syrups, consumers prefer thicker, deep-coloured ones because they remind them of good old homemade ones. Physical properties – as viscosity, colour, refractive index, soluble solid content (SSC), and electrical impedance - of fruit syrups flavoured with raspberry or orange juice were determined. The change of the measured physical properties was determined in three different experiments: 1. evaluating the effect of sugar and sweetener content 2. evaluating the effect of fruit juice composition and 3. evaluating the effect of sugar content on syrups containing raspberry or orange juice only. Variations in fruit and sugar content had a definite effect on the physical properties of squashes. Viscosity, SSC value, refractive index, and impedance magnitude increased with increasing sugar content and decreased with replacement of sugar with sweeteners although colour characteristics were defined mostly by the colorant added to the squash. Changes in the fruit composition of syrups could influence viscosity, refractive index, and SSC values but the magnitude of impedance showed little changes for all samples. The characteristics of squashes containing only raspberry or orange juice and different sugar content did not follow any trends, which emphasized that additives had a significant effect on the physical properties.

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Abstract  

Copolymers of dimethyl itaconate (DMI) and 4-vinylpyridine (4VP) were synthetized in toluene at 60C with0.26 mol% of AIBN as initiator. Their compositions were determined by differential refractometry and by differential scanning calorimetry. The 4VP contents of the copolymer samples ranged between 7 and 75 mol%. The reactivity ratios calculated via the Fineman-Ross method were r 1=0.24 (DMI) and r 2=0.57 (4VP). The thermal degradations of these copolymers were studied. The results of thermogravimetric measurements indicated that the copolymers degrade at lower temperatures than those of their parent homopolymers. A possible explanation of this anomalous behaviour is the formation of thermally unstable structures during the copolymerisation.

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) , “ Determination of dry matter (by weight/refractometry) ” 12145 ( 2000 ). Bulgarian State Standard (BDS) , “ Determination of fat ” 6997 ( 1984 ). Bulgarian State Standard (BDS) , “ Determination of proteins ” 14431 ( 1978 ). Bulgarian State Standard (BDS

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colorimetry and refractometry methods [ 13 ], and HPLC [ 14–17 ]. However, to the best of our knowledge, the simultaneous determination of CQ and the adulterants PAR and ASP in pharmaceutical preparations and breast milk has not been reported. The possibility

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