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Best Properties (best + property)
Selected AbstractsRough approximation by dominance relationsINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 2 2002Salvatore Greco In this article we are considering a multicriteria classification that differs from usual classification problems since it takes into account preference orders in the description of objects by condition and decision attributes. To deal with multicriteria classification we propose to use a dominance-based rough set approach (DRSA). This approach is different from the classic rough set approach (CRSA) because it takes into account preference orders in the domains of attributes and in the set of decision classes. Given a set of objects partitioned into pre-defined and preference-ordered classes, the new rough set approach is able to approximate this partition by means of dominance relations (instead of indiscernibility relations used in the CRSA). The rough approximation of this partition is a starting point for induction of if-then decision rules. The syntax of these rules is adapted to represent preference orders. The DRSA keeps the best properties of the CRSA: it analyses only facts present in data, and possible inconsistencies are not corrected. Moreover, the new approach does not need any prior discretization of continuous-valued attributes. In this article we characterize the DRSA as well as decision rules induced from these approximations. The usefulness of the DRSA and its advantages over the CRSA are presented in a real study of evaluation of the risk of business failure. © 2002 John Wiley & Sons, Inc. [source] Genotypic and technological characterization of Lactococcus lactis isolates involved in processing of artisanal Manchego cheeseJOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2009P. Nieto-Arribas Abstract Aims:, Genotypic and technological characterization of wild lactococci isolated from artisanal Manchego cheese during the ripening process for selection of suitable starter cultures. Methods and Results:, A total of 114 isolates of lactococci were typed using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Sixteen distinct RAPD-PCR patterns, at a similarity level of 73%, were obtained. On the basis of species-specific PCR reaction, the isolates were assigned to the species Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris with L. lactis subsp. lactis being predominant at both dairies. Twenty-six isolates were technologically characterized to select those with the best properties. Most of them showed good technological properties although some could produce tyramine. Conclusions:, The presence of coincident genotypes at both dairies has been demonstrated, which would suggest that they are well adapted to the Manchego cheese environment. Interesting differences were found in the technological characterization and the potential role of autochthonous lactococci strains as starter culture has been displayed. Significance and Impact of the Study:, The great economic importance of Manchego cheese encouraged a deeper knowledge of its microbiota, to select strains with the best properties to use as starter cultures in industrial Manchego cheeses, preserving the autochthonous characteristics. [source] Nanoclay and long-fiber-reinforced composites based on epoxy and phenolic resinsJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2008Gang Zhou Abstract In this study, high-performance thermoset polymer composites are synthesized by using both long fibers and nanoclays. Epoxy and phenolic resins, the two most important thermoset polymers, are used as the polymer matrix. The hydrophobic epoxy resin is mixed with surface modified nanoclay, while the hydrophilic phenolic resin is mixed with unmodified raw nanoclay to form nanocomposites. Long carbon fibers are also added into the nanocomposites to produce hybrid composites. Mechanical and thermal properties of synthesized composites are compared with both long-fiber-reinforced composites and polymer- layered silicate composites. The optimal conditions of sample preparation and processing are also investigated to achieve the best properties of the hybrid composites. It is found that mechanical and thermal properties of epoxy and phenolic nanocomposites can be substantially improved. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 [source] Ceramometal Bonded Inlays and OnlaysJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 3 2000HARRY F. ALBERS DDS ABSTRACT Porcelain-fused-to-metal (PFM) is presently the most popular crown and bridge technique. Its success is attributable to the use of a metal substructure to support the porcelain, resulting in good esthetics, limited ceramic flexure, and better longevity than all-porcelain restorations. A new concept suggests encapsulating the metal substructure with ceramic and placing the insert under the occlusal surface, thereby combining the best properties of the esthetics of porcelain and the support of metal to achieve improved restorations. CLINICAL SIGNIFICANCE The ceramometal bonded restoration (CMBR) addresses the known limitations of PFMs by providing a more esthetic, more conservative, and more durable alternative. The CMBR eliminates the potential for tooth darkening, leaves more of the natural tooth intact, and offers good resistance to fracture or displacement under occlusal forces. This combination of features makes the CMBR inlay or onlay an excellent alternative for the conservative esthetic restoration of posterior teeth. [source] Synthesis and biodistribution of novel 99mTc-nitrido methylpiperidine dithioformate derivatives as potential brain imaging agentsJOURNAL OF LABELLED COMPOUNDS AND RADIOPHARMACEUTICALS, Issue 6 2009Jie Lu Abstract Three dithioformate ligands with methyl substituted on the piperidine rings, potassium 1-(2-methylpiperidine-1-yl)-dithioformate (2-mp), potassium 1-(3-methylpiperidine-1-yl)-dithioformate (3-mp) and potassium 1-(4-methylpiperidine-1-yl)-dithioformate (4-mp) were synthesized. The corresponding 99mTc-nitrido complexes were prepared in high yield (>95%) through the [99mTcN] intermediate and characterized by thin layer chromatography and high-performance liquid chromatography. All the neutral 99mTc-nitrido complexes were stable under physiological conditions and lipophilic with log,P values between 1.40 and 1.58. In vivo biodistribution results showed that all the 99mTc-nitrido complexes displayed high brain uptakes and long retention times. Among them, 99mTcN-4mp, demonstrated the best properties for brain imaging with the brain uptake 3.40±0.24, 3.22±0.31, 2.72±0.28 and 2.22±0.18% ID/g at 5, 30, 60 and 120,min p.i., respectively. Moreover, the influence of stereochemistry of the 99mTcN complexes with methyl substitution on ortho, meta and para positions on piperidine ring on the biodistribution properties were investigated with B3LYP/6-31G*(LANL2DZ for Tc) method using the Gaussian 03 program package. Copyright © 2009 John Wiley & Sons, Ltd. [source] Nanopowder Preparation and Dielectric Properties of a Bi2O3,Nb2O5 Binary System Prepared by the High-Energy Ball-Milling MethodJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 1 2008Di Zhou The high-energy ball-milling (HEM) method was used to synthesize the compositions of BiNbO4, Bi5Nb3O15, and Bi3NbO7 in a Bi2O3,Nb2O5 binary system. Reagent Bi2O3 and Nb2O5 were chosen as the starting materials. The X-ray diffraction patterns of the three compositions milled for different times were studied. Only the cubic Bi3NbO7 phase, Nb2O5, and amorphous matters were observed in powders after being milled for 10 h. After heating at proper temperatures the amorphous matters disappeared and the proleptic phases of BiNbO4 and Bi5Nb3O15 could be obtained. The Scherrer formula was used to calculate the crystal size and the results of nanopowders are between 10 and 20 nm. The scanning electron microscopy photos of Bi3NbO7 powders showed drastic aggregation, and the particle size was about 100 nm. The dielectric properties of ceramics sintered from the nanopowders prepared by HEM at 100,1 MHz and the microwave region were measured. Bi3NbO7 ceramics showed a good microwave permittivity ,r of about 80 and a Q×f of about 300 at 5 GHz. The triclinic phase of BiNbO4 ceramics reached its best properties with ,r=24 and Q×f=14 000 GHz at about 8 GHz. [source] Preparation of smallest microparticles of poly- D,L -lactide by modified precipitation method: Influence of the process parametersMICROSCOPY RESEARCH AND TECHNIQUE, Issue 2 2008Ivana Jovanovi Abstract Biodegradable microspheres such as those made of poly- D,L -lactide (PDLLA) are widely investigated delivery systems for drugs or antigens. The aim of this study was to examine experimental conditions in order to produce PDLLA microspheres with the best properties for controlled and sustained drug delivery by the modified precipitation method. For this purpose, the following parameters were varied: co-solvent (methanol or ethanol), the concentration of stabilizer polyvinyl alcohol (PVA), chloroform-to-water ratio and the speed and time of homogenization. Scanning electron microscopy (SEM) and stereological analysis were used to characterize the particles. The average size and morphology of the microspheres varied substantially with preparation conditions from 8.44,1.25 ,m. Results showed that the smallest particles were obtained with methanol, 1% PVA and with 10 min of homogenization at 21,000 rpm. Microsc. Res. Tech., 2008. © 2007 Wiley-Liss, Inc. [source] Amphiphilic block copolymers of PtBA- b -PMMA as compatibilizers for blends of PET and PMMAPOLYMER ENGINEERING & SCIENCE, Issue 9 2006B. Dewangan PET and PMMA were blended at various weight fractions. These blends were compatibilized by employing amphiphilic block copolymers of PtBA- b -PMMA, having three compositions (1:3, 1:1, 3:1) and three weight fractions (3, 5, and 7 wt%) using a co-rotating twin screw extruder. The blends were evaluated for their mechanical, rheological, and morphological properties. Overall, the compatiblized blends showed improvement in properties compared with the properties of noncompatiblized blends. Mechanical properties of the compatibilized blends improved with an increase in the PMMA and compatibilizer weight fractions. It was observed that the compatibilizer with lower molecular weight and lower glass transition temperature, typically at 5 wt%, provided the overall best properties. POLYM. ENG. SCI. 46:1147,1152, 2006. © 2006 Society of Plastics Engineers. [source] | |||||||||||||