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11.
Magorzata T. Kaczmarek Izabela Pospieszna-Markiewicz Maciej Kubicki Wanda Radecka-Paryzek 《Inorganic chemistry communications》2004,7(12):1247-1249
The one-step metal promoted reaction between salicylaldehyde and 4-methyl-1,3-phenylenediamine in the presence of lanthanum(III) or gadolinium(III) nitrate yields new salicylaldimine complexes containing N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine as a result of the [2 + 1] Schiff base condensation. The crystal structure of the gadolinium complex reveals a dinuclear species with four unionized ligands coordinating in the monodentate and bridging bidentate fashion, using exclusively the oxygens as donor atoms with the nitrogen atoms not being involved in coordination. The coordination number of nine is achieved by involving three bidentate nitrate counterions in the coordination sphere. 相似文献
12.
Diana Tomás Joana Rodrigues Ana Varela Maria Manuela Veloso Wanda Viegas Manuela Silva 《International journal of molecular sciences》2016,17(2)
Genomic diversity of Portuguese accessions of Avena species—diploid A. strigosa and hexaploids A. sativa and A. sterilis—was evaluated through molecular and cytological analysis of 45S rDNA, and other repetitive sequences previously studied in cereal species—rye subtelomeric sequence (pSc200) and cereal centromeric sequence (CCS1). Additionally, retrotransposons and microsatellites targeting methodologies—IRAP (inter-retrotransposon amplified polymorphism) and REMAP (retrotransposon-microsatellite amplified polymorphism)—were performed. A very high homology was detected for ribosomal internal transcribed sequences (ITS1 and ITS2) between the species analyzed, although nucleolar organizing regions (NOR) fluorescent in situ hybridization (FISH) analysis revealed distinct number of Nor loci between diploid and hexaploid species. Moreover, morphological diversity, evidenced by FISH signals with different sizes, was observed between distinct accessions within each species. pSc200 sequences were for the first time isolated from Avena species but proven to be highly similar in all genotypes analyzed. The use of primers designed for CCS1 unraveled a sequence homologous to the Ty3/gypsy retrotransposon Cereba, that was mapped to centromeric regions of diploid and hexaploid species, being however restricted to the more related A and D haplomes. Retrotransposon-based methodologies disclosed species- and accessions-specific bands essential for the accurate discrimination of all genotypes studied. Centromeric, IRAP and REMAP profiles therefore allowed accurate assessment of inter and intraspecific variability, demonstrating the potential of these molecular markers on future oat breeding programs. 相似文献
13.
M. F. Viegas L. M. Abrantes J. Lecoeur 《Journal of materials science. Materials in medicine》1990,1(2):105-109
The aim of this work is to illustrate the use of a reliable electrochemical technique — chronoamperometry — for the study of the biodegradation process that metal alloys suffer in the human body. The designedin vitro experiments, simulating in a short period the situationin vivo, can be used to quantify the materials corrosion resistance. Data on the amount of released materials can also be obtained which is valuable information for research on biocompatibility. 相似文献
14.
The Wigner-Ville distribution of a multi-component signalhas a unique structure. Based on this structure, a formant and pitchestimation method for speech signals is introduced. Formants andpitch estimated with this method are more accurate, have betterresolution, and are easier to recognize than those estimated by othermethods. A one pitch-period segment is adequate for formantestimation while a minimal two pitch-period segment is needed forboth pitch and formant detection with one step. Experimental resultsare provided to demonstrate the performance of this method, andcomparisons with other methods are provided. 相似文献
15.
ManyEyes: a site for visualization at internet scale 总被引:1,自引:0,他引:1
Viegas FB Wattenberg M van Ham F Kriss J McKeon M 《IEEE transactions on visualization and computer graphics》2007,13(6):1121-1128
We describe the design and deployment of Many Eyes, a public web site where users may upload data, create interactive visualizations, and carry on discussions. The goal of the site is to support collaboration around visualizations at a large scale by fostering a social style of data analysis in which visualizations not only serve as a discovery tool for individuals but also as a medium to spur discussion among users. To support this goal, the site includes novel mechanisms for end-user creation of visualizations and asynchronous collaboration around those visualizations. In addition to describing these technologies, we provide a preliminary report on the activity of our users. 相似文献
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Friedlander Myrna L.; Highlen Pamela S.; Lassiter Wanda L. 《Canadian Metallurgical Quarterly》1985,32(2):171
Conducted a multidimensional content analysis of 4 expert counselors' (N. Ackerman, M. Bowen, D. Jackson, and C. Whitaker) approaches to family treatment. Data were from the 1969 Hillcrest Families Series (produced by R. Birdwhistell), films of these experts conducting assessment interviews with the same family. The natural language in these interviews reveal that Ss' behaviors both converged and diverged. Although these Ss did not represent separate theoretical schools, the distinctive features in their sessions were consistent with their theoretical emphases. Across interviews, commonalities included (a) the parents as the most active participants; (b) a focus on the parental subsystem; and (c) similar proportions of certain types of counselor responses (e.g., informative directives). A fair proportion of Ss' messages were indirect (addressed to someone other than the target of the communication). Based on these results and an earlier study by the 1st 2 authors (see record 1985-07308-001) of the same interviews, 2 common change factors in family counseling are proposed: disruption of the existing balance of power among family members and education in the nature and strength of family systems. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Coals of different rank were treated with naphthalene anion in tetrahydrofuran. It was found that, as in the case of coal of 87.8% C (daf), large amounts of unreactive oxygen bonds, possibly of the ether type, were cleaved. Cleavage of these ether linkages led to a lowering of the melting point and, in some types of coals, to a large increase in dilatation and a substantial increase in Gieseler fluidity. 相似文献
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20.
Katarzyna Skryplonek Marta Henriques David Gomes Jorge Viegas Catarina Fonseca Carlos Pereira Izabela Dmytrów Anna Mituniewicz-Małek 《Journal of dairy science》2019,102(9):7838-7848
Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer. 相似文献