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31.
A study to evaluate the value and potential use of colostral enzymes as markers for the evaluation of buffalo colostrum quality was conducted. The enzymes gamma-glutamyltransferase (GGT), lactic dehydrogenase (LDH), and alkaline phosphatase (ALP) in buffalo's colostrum were measured spectrophotometrically, and their activities were correlated with the gamma-globulin content. Gamma-globulin concentration was determined following the electrophoretic separation of the colostral proteins and quantified with a densitometer. Colostrum was obtained from 15 dams, soon after calving. Means, standard deviations, correlation coefficients, and degree of significance were calculated using the general linear model procedure of the Statistical Analysis Systems program. The activity of GGT in the colostrum was the highest, followed by LDH and ALP. A significant correlation (r = 0.86; P < 0.001) was seen between GGT and gamma-globulin concentration in the colostrum, supporting the suggestion of using this enzyme as a marker for the evaluation of colostrum quality. 相似文献
32.
P. Elias C. Kontoes O. Sykioti A. Avallone S. Van Gorp P. Briole 《International journal of remote sensing》2013,34(14):3079-3086
On 7 September 1999 a magnitude MW = 5.9 earthquake occurred in the Athens area of Greece producing a subsidence of 6–7 cm detected by radar interferometry. This study introduces a processing technique, which produces a clear deformation pattern of the earthquake, mostly released from artefacts due to orbital effects, unwrapping cycle slipping errors and atmospherics disturbances. A set of 17 ERS‐1 and ERS‐2 SAR images acquired between December 1997 and January 2001 has been used. The contribution of each artefact to the interferograms was calculated, both in the frequency and spatial domains. 相似文献
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Jose García-Torres Elvira Gómez Elisa Vallés 《Journal of Applied Electrochemistry》2009,39(2):233-240
Cobalt electrodeposits were prepared from an electrolytic bath containing cobalt perchlorate. The effect of different species,
organic (thiourea and sodium gluconate) and inorganic (boric acid), on the crystallographic structure, morphology, magnetic
properties and electrochemical behaviour of cobalt electrodeposits was investigated. Amorphous cobalt, hcp cobalt and a non-usual
primitive cubic cobalt phase were observed depending on the bath composition. Depending on the structure, different morphologies
and magnetic properties were found. Coercivity values of the cobalt coatings ranged from around 15 Oe for amorphous, nodular
deposits to 380 Oe for cobalt coatings showing acicular morphology and hcp structure with a (002) preferred orientation. Knowledge
of the influence of the species on the properties of cobalt makes it possible to obtain tailored cobalt films. 相似文献
35.
Ivano Camoni Riccardo Fabbrini Leonello Attias Alfonso Di Muccio Elvira Cecere Antonio Consolino Francesca Roberti 《Food Additives & Contaminants》2001,18(10):932-936
In 1997 the Italian monitoring programme for pesticide residues in food comprised 7951 samples of 152 different foods for which a total of 275 pesticides were analysed. For 90 pesticides, the National Estimated Daily Intakes (NEDIs) were calculated by using the 90th percentile value and the food consumption data for the general Italian population. The calculated NEDIs were found to represent only a small portion of the respective Acceptable Daily Intake (ADI). 相似文献
36.
Stefania Vichi Montserrat Riu-Aumatell Mercé Mora-Pons Josep M. Guadayol Susana Buxaderas Elvira López-Tamames 《Food chemistry》2007,105(4):1748-1754
HS-SPME coupled to GC/MS was applied to the analysis of the volatile fraction of Juniperus communis L. berries, which are the principal ingredient used for gin aromatization. Seventy seven compounds were identified by comparison with reference compounds or tentatively identified by comparing their mass spectra and retention index with those reported in mass spectra libraries and literature, respectively. Seventy four were detected by SPME and sixty eight were detected by solvent distillation extraction (SDE). These were mainly mono- and sesquiterpenic compounds that represented more than the 80% of the gin’s volatile composition. A high percent content was due to monoterpenoids, whose analysis could be important for the assessment of sensory quality control of juniper due to their impact on gin aroma. The main monoterpenoids detected in the headspace of the juniper berries from two periods of collection were terpinen-4-ol, p-cymene, β-myrcene, γ-terpinene, α-pinene and limonene. These represented more than the 70% of the sample’s volatile fraction. The proposed SPME method required short times and the low cost of analysis and enabled to detect a number of compounds comparable with SDE or much higher than the number of compounds reported by other extraction techniques. The results suggested the suitability of this technique for the assessment of the volatile composition of juniper berries intended for gin flavouring. 相似文献
37.
Electrodeposition of Co-Ni and Co-Ni-Cu alloys was performed in a sulphate-citrate medium. Experimental electrodeposition parameters (pH, cobalt(II), nickel(II) and citrate concentrations) were varied in order to analyse their influence on the deposition. Anomalous Co-Ni codeposition occured in the citrate medium. High [Ni(II)]/[Co(II)] ratios (above 5) were suitable for the preparation of homogeneous magnetic Co-rich Co-Ni deposits of hexagonal close-packed (hcp) structure or face centred cubic (fcc) structure as a function of the deposition potential.The presence of very low copper(II) concentrations (<10−2 mol dm−3) in the nickel-cobalt bath makes it possible to incorporate copper in the deposits in amounts ranging from 5 to 60% Cu, although uniform deposits are obtained only for low copper percentages. These ternary deposits are solid solutions with fcc structure and magnetic behaviour both dependent on the deposition potential. 相似文献
38.
P.D Sanz L Otero C de Elvira J.A Carrasco 《International Journal of Refrigeration》1997,20(5):301-307
Experimental freezing of water in high-pressure domain is studied considering temperature reduction (TRF) as well as high-pressure-assisted freezing (HPAF). The most important advantage of HPAF is that the whole volume of the sample is subcooled when an expansion is made, so a rapid and uniform nucleation and growth of ice crystals are produced. In this work through mathematical modelling the amount of ice appearing instantaneously in the latter freezing, is predicted. 相似文献
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