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101.
I. Batista I. Vidal H. M. Lourenço I. Sousa M. L. Nunes 《European Food Research and Technology》1999,210(1):31-33
Clams are widely used in the preparation of several seafood dishes but there are still a few bivalve species which have not been extensively used. Among these species is dog cockle (Glycymeris glycymeris), which is a major by-catch of surf clam (Spisula solida) fishing. However, dog cockle has a low commercial value because its texture is too tough after cooking. This study was initiated to find the best way of tenderising the meat of this species to make it suitable for human consumption. Based on preliminary trials using different tenderising products, a mixture of sodium tripolyphosphate and sodium chloride (3% and 1.5% respectively) was considered the most effective. The optimization of the processing parameters (time and temperature) was done by response surface methodology. According to the sensory analysis, objective texture evaluation and phosphate determinations the optimum conditions for the tenderisation process were an immersion time of 3 h at a temperature of 20 °C. The tenderised meat was used in the preparation of two types of canned products (light brine and a pickling sauce known as "escabeche"), which were evaluated by a taste panel and judged satisfactory. 相似文献
102.
To evaluate the clinical significance of serum levels of hepatocyte growth factor (HGF) in colorectal cancer patients, we measured the venous and portal concentrations of HGF in 60 patients. The tissue concentrations in the tumour and adjacent normal mucosa were also determined. The serum HGF concentration for the peripheral venous blood of the patients was significantly higher than that in normal controls. The content of HGF in cancer tissue was also significantly higher than that in normal mucosa, and it was correlated with the serum HGF concentration for the peripheral venous blood. The serum concentration of HGF reflected pathological features, including tumour size and lymph node or liver metastasis, and it showed an association with various preoperative nutritional parameters and the preoperative haemoglobin level. The serum HGF concentration was also correlated with the serum concentrations of immunosuppressive acidic protein and interleukin-6, indices of the host's immunological condition. Serum HGF seems to be a useful index of the disease status of patients with colorectal carcinoma. 相似文献
103.
C. S. dos Santos T. S. E. Maibaum A. L. Furtado 《International journal of parallel programming》1981,10(5):299-314
A formalism adequate for the specification of behavioral properties of data bases is proposed. The formalism is a many-sorted first order predicate calculus, including a formalized notion of data base state. Both update and query requests are modeled through expressions by the use of predicates supplied in the language of the formal system, and are treated uniformly as a theorem proving process. The process consists of using the axioms defining the data base for either synthesizing a valid sequence of update operations (if such exists) or for answering the query. 相似文献
104.
105.
The kinetics of reduction of soluble polymeric MnO2 by cysteine and glutathione has been studied in the pH range of 4.0-9.0. The concentration of thiols was varied between 1 and 2 mM, while the MnO2 concentration was varied between 2 and 12 microM. In this pH range, the reaction products were identified as Mn(II) and the corresponding disulfides (cystine and glutathione disulfide). Cysteic or cysteine sulfonic acid was formed only when pH < 2. Experimental data indicate that the rate law over the pH range of 4-9 is first-order in both MnO2 and thiol concentration. Eyring plots for both thiols reacting with MnO2 indicate that the reaction is associative (deltaS(double dagger) approximately -160 J mol(-1) K(-1)) and proceeds via an inner-sphere redox process. The reaction proceeds via the formation of two different inner-sphere complexes [triple bond]Mn(IV)SR- and [triple bond]Mn(IV)SR and their further reaction to products. Both surface species are linked to each other via acid-base equilibria, and the rate constant decreases as pH increases. The presence of two ligand surface species is determined using surface complexation modeling. A reaction mechanism in agreement with the experimental results is proposed. 相似文献
106.
Huguenin JA Coutinho dos Santos B dos Santos PA Khoury AZ 《Journal of the Optical Society of America. A, Optics, image science, and vision》2003,20(10):1883-1889
We present a study of spatial structures created by superposition of spiral zone plates used for generating optical beams with phase singularities. Moiré fringes are observed that show topological defects similar to those appearing in interference patterns of optical vortices. A brief theoretical discussion is included that supports the similarities between the two phenomena. Our results may lead to interesting applications to digital information processing by optical means. 相似文献
107.
Nonhydrolytic sol-gel synthesis and characterization of YAG 总被引:1,自引:0,他引:1
Eduardo José Nassar Paula Fabiana dos Santos Pereira Evelisy Cristina de Oliveira Nassor Lilian Rodrigues Ávila Katia Jorge Ciuffi Paulo Sergio Calefi 《Journal of Materials Science》2007,42(7):2244-2249
Yttrium–aluminum oxides are interesting compounds, which are widely used as hosts for lasers and phosphors due to their stable
physical and chemical properties. The manufacture of YAG has been investigated thoroughly. YAG powders are traditionally synthesized
through the reaction of aluminum and yttrium powders at high temperatures. The work reported here involved an investigation
into the preparation of YAG by a nonhydrolytic sol-gel route and the influence of heating time at low temperatures to obtain
YAG from inorganic precursors (yttrium and aluminum chloride). AlCl3, YCl3 and ethanol were reflux reacted under an argon atmosphere. Europium III chloride was added as a structural probe. The powder
was treated at 800 °C for 1, 2, 4, 8 and 16 h. The YAG structure was analyzed by X-ray diffraction (XRD), nuclear magnetic
resonance (NMR), thermal analysis (TA) and photoluminescence (PL). The XRD revealed only peaks corresponding to the YAG phase.
PL data showed that the YAG phase was formed in 2 min with samples pretreated at 50 °C. For the samples pretreated at 800 °C,
the YAG phase appeared in 30 s. The excitation spectra presented a maximum of 394 nm corresponding to the 5L6 level, while the emission spectra of Eu III ions showed characteristic transition bands arising from the 5D0 → 7F
J
(J = 1, 2, 3, 4) manifolds at maximum excitation. The magnetic dipole 5D0 → 7F1 transition exhibited greater intensity than the electric dipole 5D0 → 7F2 transition. This methodology proved efficient for obtaining YAG phase. 相似文献
108.
Derval dos Santos Rosa Flávia Gaboardi Cristina das Graças Fassina Guedes Maria Regina Calil 《Journal of Materials Science》2007,42(19):8093-8100
Blends of poly(β-hydroxybutyrate) (PHB) and low density polyethylene (LDPE) were prepared in proportions of 100/0, 75/25,
50/50, 27/75 and 0/100 (PHB/LDPE wt.%), with and without oxidized polyethylene wax (OPW, 5 wt.%), and the mechanical, thermal
(differential scanning calorimetry and melting flow index, morphological (scanning electron microscopy) and biodegradation
(aging in simulated soil) properties were evaluated. The addition of OPW increased the tensile strength and Young’s modulus
but decreased the elongation at break of the blends. Similarly, OPW increased the T
g
of the pure LDPE and enhanced the melt flow index. Scanning electron microscopy showed that OPW reduced the phase separation
of LDPE and increased the biodegradation during aging in simulated soil. 相似文献
109.
Leonardo Augusto dos Santos Vieira Sergio Fernando Mayerle Carolina Luisa dos Santos Vieira Mônica Maria Mendes Luna 《Optimization and Engineering》2016,17(4):761-780
Available productive capacity is determinant of a company’s success once it allows meeting the current and future demand. This article proposes a quantitative model for determining long-term productive capacity in competitive oligopolistic markets, based on the Nash Equilibrium formulated as a Variational Inequality problem. Numerical examples enable an analytical evaluation of the economic equilibrium’s sensitivity to marginal costs, investment costs, hurdle rate, and market saturation. Results show that, in order to achieve a greater market share, it is important to adopt strategies that reduce marginal costs. On the other hand, variations in the hurdle rate may or may not reinforce the position of a competitor in the market and his interest in investing in capacity expansion. Additionally, market saturation may be achieved, beyond which investment becomes unattractive. Each of these is a positive outcome for society, triggering diversified investments and competition in economic sectors where competition is low and profits are high. 相似文献
110.
André Miguel F. Santos Rosa Maria dos Santos Pedro Miguel A.C. Castro Elsa Azevedo Luísa Sousa João Manuel R.S. Tavares 《Expert systems with applications》2013,40(16):6570-6579
A novel algorithm is proposed for the segmentation of the lumen and bifurcation boundaries of the carotid artery in B-mode ultrasound images. It uses the image contrast characteristics of the lumen and bifurcation of the carotid artery in relation to other tissues and structures for their identification. The relevant ultrasound data regarding the artery presented in the input image is identified using morphologic operators and processed by an anisotropic diffusion filter for speckle noise removal. The information obtained is then used to define two initial contours, one corresponding to the lumen and the other one regarding the bifurcation boundaries, for the application of the Chan-Vese level set segmentation model. A set of longitudinal ultrasound B-mode grayscale images of the common carotid artery was acquired using a GE Healthcare Vivid-e ultrasound system. The results reveal that the new algorithm is effective and robust, and that its main advantage relies on the automatic identification of the carotid lumen, which overcomes the known limitations of the traditional algorithms. 相似文献