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991.
Ricardo N. Marreto Maria P. G. Peixoto Luciana A. Tacon Luis A. P. Freitas 《Drying Technology》2007,25(5):821-830
The stimulus response methodology was evaluated in an experimental study conducted to measure NaCl solution residence time distributions in a spouted bed dryer of inert particles. The influence of tracer volume, concentration, and injection mode upon the measured mean residence time and residence time distribution was determined following experimental design techniques. The injection mode showed no significant effect on residence times, whereas tracer volume and concentration had significant effects at the levels of 1 and 5%, respectively, under the conditions chosen initially. The steepest ascent and factorial design methods were applied to determine the range in parameters for optimum stimulus response. The procedure repeated for a polymeric paste showed similar results. However, the results also showed that care must be exercised when using the stimulus response technique and the optimum injection conditions must be determined. The procedure presented in this study may be adopted in future investigations of paste residence time distributions in spouted bed dryers of inert bodies. 相似文献
992.
Biophysical principles which relate to the interaction of microwaves to biological material and man are summarized. The limitations of animal experimentation and the usefulness of biophysical considerations are indicated, and the absorption of microwaves by tissues is discussed. 相似文献
993.
Talha Ahmad Muhammad Zubair Butt Rana Muhammad Aadil Muhammad Inam‐ur‐Raheem Abdullah Alaa El‐Din Bekhit Jonas T Guimares Celso F Balthazar Ramom S Rocha Erick A Esmerino Mnica Q Freitas Mrcia C Silva Aysha Sameen Adriano G Cruz 《International Journal of Dairy Technology》2019,72(4):481-495
Milk is highly perishable and deteriorates rapidly during storage. Although the thermal processing technologies successfully inactivate many enzymes and microorganisms up to a required level, they can negatively affect the natural flavour of dairy foods and decrease their nutritional value. Alternative nonthermal technologies have been established as an interesting approach to produce safe and healthy dairy products, without compromising their nutritional quality. These techniques have the ability to inactivate milk enzymes without affecting the milk quality. In addition, the combination of two different nonthermal techniques and mild heating has proven to be more effective to provide safety to milk when compared to the treatments alone. This review aims to evaluate the impact of nonthermal technologies, in particular, ultrasound, pulsed electric field, high‐pressure processing and ultraviolet irradiation on milk enzymes. 相似文献
994.
Erick A. Esmerino Juliana P. Ferraz Elson R. Tavares Filho Letícia P.F. Pinto Mônica Q. Freitas Adriano G. Cruz Helena M.A. Bolini 《Journal of dairy science》2017,100(11):8849-8860
Yogurts, fermented milk beverages, and fermented milks have great similarity and are widely accepted by Brazilian population, but the factors that influence their choice and consumption are unknown. In this sense, the present study aimed to identify the main aspects involved in consumers' perception of 3 different products, comparing the findings by using the 2 fast qualitative methods, word association and projective mapping, and a standard method, focus group. The tasks were performed by different participants through graphic stimuli (word association and projective mapping) and focus interviews (focus group). Results showed that all the 3 methodologies identified numerous intrinsic and extrinsic factors that influence the consumer choices regarding fermented dairy products. Major dimensions were closely related to the sensory aspects, emotional factors, perception of benefits, and composition, among others. It is noteworthy that the stimuli related to fermented milk beverages evoked rejecting responses, possibly due to the dissociation between information and consumers' expectation. Although minor differences were observed between the number and type of dimensions that were obtained, similar conclusions can be drawn from all 3 sensory methods, which shows the relevance of qualitative and projective methods for investigation of consumers' perception. These findings can help dairy companies to provide subsidies and guidelines for the reformulation of their products, marketing strategies, and improvement in the communication between producers and consumers from different fermented dairy products. 相似文献
995.
Increased protein content of chickpea (Cicer arietinum L.) inoculated with arbuscular mycorrhizal fungi and nitrogen‐fixing bacteria under water deficit conditions
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996.
Pamela I. Otto Simone E.F. Guimarães Lucas L. Verardo Ana Luísa S. Azevedo Jeremie Vandenplas Claudia A. Sevillano Daniele B.D. Marques Maria de Fatima A. Pires Célio de Freitas Rui S. Verneque Marta Fonseca Martins João Cláudio C. Panetto Wanessa A. Carvalho Diego O.R. Gobo Marcos Vinícius G.B. da Silva Marco A. Machado 《Journal of dairy science》2019,102(9):8148-8158
997.
This paper reports the purification and analysis of magnetic nanoparticles using capillary magnetic field flow fractionation, which utilizes an applied magnetic field oriented orthogonal to the capillary flow. To validate this approach as a separation method for nanometer-scale particles, samples of magnetic nanoparticles composed of either gamma-Fe2O3 (maghemite) or CoFe2O4 with average diameters ranging from 4 to 13 nm were prepared and characterized by transmission electron microscopy and SQUID magnetometry. Retention of the samples on the capillary was investigated as a function of solvent flow rate and the nanoparticle size and composition; the elution times of the nanoparticles are strongly dependent on their magnetic moments. We demonstrate the use of this method to separate a mixture of nanoparticles into size-monodisperse fractions. The magnetic moments of the particles are calculated based on analysis of the retention parameters and correlate with values obtained in separate SQUID magnetometry measurements. 相似文献
998.
Reaction Between Malvidin 3-Glucoside and (+)-Catechin in Model Solutions Containing Different Aldehydes 总被引:1,自引:0,他引:1
J. Pissarra N. Mateus J. Rivas-Gonzalo C. Santos Buelga V. De Freitas 《Journal of food science》2003,68(2):476-481
ABSTRACT: The contribution of the aldehyde composition of wine spirit to the color changes in Port red wine was studied in model solutions. Malvidin 3-glucoside was shown to be very reactive towards catechin in the presence of different aldehydes: acetaldehyde, isovaleraldehyde, benzaldehyde, propionaldehyde, isobutyraldehyde, formaldehyde, and 2-methylbutyraldehyde. LC/MS data confirmed the formation of oligomeric pigments resulting from the reaction between the anthocyanin and the flavanol (colored products) and between 2 flavanol units (colorless products) mediated by each aldehyde assayed. The UV-visible spectra of the colored pigments showed a λmax bathochromically shifted relatively to the λmax of original anthocyanins. All samples revealed a "blueing" and "darkening" color effects using the CIELAB system. 相似文献
999.
J Freitas J Puig J Campos JM Garcia DL Cunha MJ Carvalho O Costa MC Gomes AF Freitas 《Canadian Metallurgical Quarterly》1993,12(9):745-51, 702
The authors describe a case of a middle-age male with recurrent syncope, in whom the tilt test was useful in the diagnosis and therapeutic evaluation. Malignant criteria of vasovagal syncope were established and the beta blocking worsening effect was documented, in spite of the general agreement of the first choice drug. 相似文献
1000.
The dielectric constant and electrical conductivity of the lens of the eye have been investigated throughout the frequency range from 0.5 to 200 Mc. The values obtained are frequency dependent. The frequency dependence is found consistent with the assumption of lens fiber membranes which are characterized by a membrane capacitance of very approximately 1?f/cm2. This is typical for biological membranes in general. Thus the existence of lens fiber membranes which are similar in molecular structure to the membranes of other biological cells is indicated. The dielectric data at very high frequencies are satisfactorily explained by the lens protein content. 相似文献