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111.
112.
Daniel Oliveira de Lima Cassiano Gomes Aimoli Marisa Masumi Beppu 《Materials science & engineering. C, Materials for biological applications》2009,29(4):1109-1113
The understanding of how macromocules act in precipitation of inorganic phases is the key knowledge that is needed to establish the foundation to mimic nature and produce materials with high mechanical modulus besides outstanding optical and thermal properties. This study investigated how addition of small amounts of alginate (7–70 ppm), that presents many carboxylic groups, affects phase distribution and morphology of calcium phosphates, obtained through precipitation and further submitted to calcination and sintering. The results lead to the conclusion that alginate action is dynamic, where alginate molecules act as templates to nucleation, and most of the biopolymer remains in solution even when all calcium phosphate has precipitated. However, despite the effect on phase composition being mainly related to the system's kinetics, alginate does present thermodynamic interaction with the precipitates. It is probable that it acts by reducing the free energy of nucleation, as in heterogeneous nucleation processes. 相似文献
113.
Marisa?MoritaEmail author Robert?Sabourin Flávio?Bortolozzi Ching?Y.?Suen 《International Journal on Document Analysis and Recognition》2003,6(4):248-262
This paper presents an HMM-MLP hybrid system for segmenting and recognizing complex date images written on Brazilian bank checks. Through the recognition process, the system makes use of an HMM-based approach to segment a date image into subfields. Then the three obligatory date subfields (day, month, and year) are processed. A neural approach has been adopted to decipher strings of digits (day and year) and a Markovian strategy to recognize and verify words (month). The final decision module makes an accept/reject decision. We also introduce the concept of metaclasses of digits to reduce the lexicon size of the day and year and improve the precision of their segmentation and recognition. Experiments show interesting results on date recognition.Received: 17 December 2002, Accepted: 16 July 2003, Published online: 17 November 2003Correspondence to: Marisa Morita 相似文献
114.
Christopher Neill Paul A. Steudler Diana C. Garcia-Montiel Jerry M. Melillo Brigitte J. Feigl Marisa C. Piccolo Carlos C. Cerri 《Nutrient Cycling in Agroecosystems》2005,71(1):1-15
Tropical soils are important sources of nitrous oxide (N2O) and nitric oxide (NO) emissions from the Earths terrestrial ecosystems. Clearing of tropical rainforest for pasture has the potential to alter N2O and NO emissions from soils by altering moisture, nitrogen supply or other factors that control N oxide production. In this review we report annual rates of N2O and NO emissions from forest and pastures of different ages in the western Brazilian Amazon state of Rondônia and examine how forest clearing alters the major controls of N oxide production. Forests had annual N2O emissions of 1.7 to 4.3 kg N ha-1 y-1 and annual NO emissions of 1.4 kg N ha-1 y-1. Young pastures of 1–3 years old had higher N2O emissions than the original forest (3.1–5.1 kg N ha-1 y-1) but older pastures of 6 years or more had lower emissions (0.1 to 0.4 kg N ha-1 y-1). Both soil moisture and indices of soil N cycling were relatively poor predictors of N2O, NO and combined N2O + NO emissions. In forest, high N2O emissions occurred at soil moistures above 30 water-filled pore space, while NO emissions occurred at all measured soil moistures (18–43). In pastures, low N availability led to low N2O and NO emissions across the entire range of soil moistures. Based on these patterns and results of field fertilization experiments, we concluded that: (1) nitrification was the source of NO from forest soils, (2) denitrification was not a major source of N2O production from forest soils or was not limited by NO- supply, (3) denitrification was a major source of N2O production from pasture soils but only when NO3- was available, and (4) nitrification was not a major source of 3 NO production in pasture soils. Pulse wettings after prolonged dry periods increased N2O and NO3- emissions for only short periods and not enough to appreciably affect annual emission rates. We project that Basin-wide, the effect of clearing for pasture in the future will be a small reduction in total N2O emissions if the extensive pastures of the Amazon continue to be managed in a way similar to current practices. In the future, both N2Oand NO fluxes could increase if uses of pastures change to include greater use of N fertilizers or N-fixing crops. Predicting the consequences of these changes for N oxide production will require an understanding of how the processes of nitrification and denitrification interact with soil type and regional moisture regimes to control N2O and NO production from these new anthropogenic N sources. 相似文献
115.
Marisa Venturini Zilli 《Calcolo》1974,11(1):67-77
Two indefinite elements are considered, a stronger one and a wenker one Their existence in a particular uniformly reflexive
structure is shown. 相似文献
116.
Gillham Jane E.; Reivich Karen J.; Freres Derek R.; Lascher Marisa; Litzinger Samantha; Shatté Andrew; Seligman Martin E. P. 《Canadian Metallurgical Quarterly》2006,21(3):323
Previous studies suggest that school-based cognitive-behavioral interventions can reduce and prevent depressive symptoms in youth. This pilot study investigated the effectiveness of a cognitive-behavioral depression prevention program, the Penn Resiliency Program for Children and Adolescents (the PRP-CA), when combined with a parent intervention component. Forty-four middle school students and their parents were randomly assigned to the enhanced PRP (the PRP-CA plus parent program) or control conditions. Students completed measures of depression and anxiety symptoms at baseline and 2 weeks, 6 months, and 1 year after the intervention ended. The combined version of the PRP significantly reduced symptoms of depression and anxiety during the follow-up period. Children assigned to the intervention condition were less likely than controls to report clinical levels of anxiety symptoms. Findings suggest that school-based cognitive-behavioral interventions that include parents may prevent depression and anxiety symptoms in early adolescence. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
117.
Marisa Pecce Francesca Ceroni Andrea Prota Gaetano Manfredi 《Canadian Metallurgical Quarterly》2006,10(3):195-203
This paper deals with an innovative technique for strengthening reinforced concrete (RC) structures using steel-reinforced polymer (SRP) materials. The results of an experimental campaign using RC beams strengthened in flexure with carbon fiber-reinforced polymer or SRP laminates are summarized, and the experimental outcomes are compared to the predictions provided by analytical models and code formulations in terms of flexural strength, curvature of the cross section, deflections, and crack widths. Under ultimate conditions, the ACI 440.2R-02 approach provided conservative flexural strength, and a modified expression for the bond coefficient km was proposed. Under serviceability conditions, good agreement was obtained between experimental results and a theoretical model developed by the writers. Comparisons of code models in terms of both crack width and deflections highlighted the need for a calibration of code formulas to account for effects due to externally bonded reinforcement. 相似文献
118.
Carlos A. Osella Hugo D. Snchez Carlos R. Carrara Marisa A. de la Torre M. Pilar Buera 《Starch - St?rke》2005,57(5):208-216
The objective of the present work was to analyze molecular and supramolecular changes of bread starch and to relate bread firmness increase during storage with starch recrystallization and water hydration levels and migration in gluten‐free bread. At the studied conditions starch was in the supercooled region of the state diagram, at a temperature between Tg (glass transition temperature) and Tm (melting temperature), feasible to crystallize. The crystalline degree during storage was followed by the intensity increase in the X‐ray diffraction peaks. During bread storage, water migration occurred from the crumb towards the crust. Water amount and redistribution affected the kind of starch crystallites formed and firmness of aged bread. It was not the total amount of crystalline fraction that determined bread firmness, but the type of crystallites formed. These observations are a further evidence that bread firmness development and starch recrystallization, although being related phenomena, are obviously separate events. 相似文献
119.
Lincomycin solar photodegradation, algal toxicity and removal from wastewaters by means of ozonation 总被引:8,自引:0,他引:8
Antibiotic molecules have been reported among the xenobiotics present at trace levels in sewage treatment plant (STP) effluents and aquatic environment. Lincomycin, one of the most used in clinical practices whose presence in the STP effluents has been often documented, is submitted to an extensive investigation to assess its persistence in the environment and toxicity towards different algal strains. The possibility to remove the lincomycin from water by means of ozonation is demonstrated and a reduction of toxicity of ozonated solutions on S. leopoliensis, with respect to untreated solutions containing this compound, is obtained even just for 1h of treatment. Kinetic constants for the attack to lincomycin of ozone (from 1.53 x 10(5) M(-1)s(-1) at pH = 3.0 and 4.93 x 10(5) M(-1)s(-1) at pH = 6.7) and OH radicals (4.37 x 10(9) M(-1)s(-1) at pH = 5.5 and 4.59 x 10(9) M(-1)s(-1) at pH = 7.5) are also evaluated. 相似文献
120.
Federal courts aren't hesitating in sanctioning parties who challenge arbitration awards when the moves are rooted in delay or dissatisfaction. Marisa Marinelli and Christelette Hoey, of New York, explain 相似文献