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991.
There are two main fuzzy system methodologies for translating expert rules into a logical formula: In Mamdani's methodology, we get a DNF formula (disjunction of conjunctions), and in a methodology which uses logical implications, we get, in effect, a CNF formula (conjunction of disjunctions). For both methodologies, universal approximation results have been proven which produce, for each approximated function f(x), two different approximating relations RDNF(x, y) and RCNF(x, y). Since, in fuzzy logic, there is a known relation FCNF(x) ≤ FDNF(x) between CNF and DNF forms of a propositional formula F, it is reasonable to expect that we would be able to prove the existence of approximations for which a similar relation RCNF(x, y) ≤ RDNF(x, y) holds. Such existence is proved in our paper. © 2002 Wiley Periodicals, Inc. 相似文献
992.
Wood scantlings were coated with polyaniline (PANI) during the in situ polymerization of aniline with ammonium peroxydisulfate in an aqueous medium. The coating was made in hydrochloric or phosphoric acid solutions in both the absence and presence of stabilizers, poly(N‐vinylpyrrolidone) or colloidal silica. The PANI‐coated wood was placed in a flame or in a furnace operating at 400 or 600°C, and the decrease in the mass was determined. The wood coated with PANI was less reduced in its mass than uncoated samples and was converted to charcoal rather than to ashes. The deposition of related polymers, polypyrrole and poly(1,4‐phenylenediamine), provided similar protection against heat exposure. Fourier transform infrared and Raman spectra of the residues after the burning of PANI‐coated wood were compared. The soaking of wood in PANI colloids did not result in similar protection of wood against fire; the coating of the cellulose fibers with PANI during the polymerization was needed for the enhanced stability of wood at elevated temperatures. The concept of carbonization processes at the surface layer of PANI‐coated cellulose fibers leading to the formation of carbonaceous microtubes is offered to explain the improved stability of wood against flame and heat exposure. © 2006 Wiley Periodicals, Inc. J Appl PolymSci 103: 24–30, 2007 相似文献
993.
Alexey N. Lachinov Mikhail G. Zolotukhin Vyacheslav A. Antipin Irina L. Valeeva 《大分子材料与工程》1994,214(1):11-18
Electroluminescence of thin films of poly(3,3-phthalidylidene-4,4′-biphenylylene) (PPB) and poly(3,3-phthalidylidene-2,7-fluorenylylene) (PPF) was studied. In both cases, electroluminescene was found to be of a threshold origin. Emission maxima and quantum efficiencies for PPB and PPF are 490 and 525 nm, 0.01 and 0.1%, respectively. The electroluminescent characteristics were found to be strongly dependent on the polymer used. 相似文献
994.
Polyaniline (PANI)/Nylon‐6 composite films were prepared by oxidative polymerization of aniline (ANI) inside host Nylon‐6 film. Such a composite has the desired electro‐active and mechanical properties to serve as a self‐standing functional unit. Comparative studies on sorption of ANI by Nylon‐6 matrix from various ANI containing media were conducted revealing superior ANI uptake from neutral ANI solution in water. ANI content was measured to be as high as 12%. Spectroscopic measurements showed that hydrogen bonding seemed to play important role in ANI sorption by Nylon‐6 matrix. Polymerization was monitored using atomic force microscopy and conductivity measurements. The morphology studies showed the appearance of PANI nanodomains on Nylon‐6 surface in the early stages of the polymerization. Eventually the domains coalesced during polymerization forming a continuous PANI layer. The conductivity measurements confirmed the change of the morphology from isolated islands to continuous conducting surface by drastic increase in conductivity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
995.
Andreea Irina Cosutchi Simona‐Luminita Nica Camelia Hulubei Mihaela Homocianu Silvia Ioan 《Polymer Engineering and Science》2012,52(7):1429-1439
Two binary polyimide (PI) blends having a common monomer (diamine or dianhydride) were prepared. The first system was composed of PIs obtained from an alicyclic and flexible dianhydride, namely 5‐(2,5‐dioxotetrahydrofurfuryl)‐3‐methyl‐3‐cyclohexene‐1,2‐dicarboxylic acid anhydride (DOCDA) and two aromatic diamines: 4,4′‐oxydianiline (ODA) and p‐phenylenediamine, respectively. In the second system, ODA was combined with DOCDA and (hexafluoroisopropyldiene)diphthalic dianhydride (6FDA). Films of the resulted blends were transparent, suggesting their homogeneity. According to differential scanning calorimetry data, the existence of a single Tg intermediate to those of the pure PIs confirmed the miscibility of blends. Incorporation of aliphatic and asymmetric DOCDA moieties, hexafluoropropyldiene groups and ether linkages in the molecular structure of PIs reduced the charge transfer interactions and significantly increased transparency and optical gap energy, especially for the poly(DOCDA‐ODA)/poly(6FDA‐ODA) blend. These interactions are also reflected in viscosity dependence on shear rate, indicating that they are slightly stronger when the aromatic 6FDA component prevails. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers 相似文献
996.
Dmitry I. Petukhov Andrei A. Eliseev Irina V. Kolesnik Kirill S. Napolskii Alexey V. Lukashin Yuri D. Tretyakov Sergey V. Grigoriev Nataliya A. Grigorieva Helmut Eckerlebe 《Microporous and mesoporous materials》2008,114(1-3):440-447
Titania nanotube arrays were synthesized via anodic oxidation of titanium foils in glycerol electrolyte containing NH4F at anodization voltage ranging from 10 V to 30 V. The structural parameters of self-organized periodic arrays of titania nanotubes were determined by small-angle neutron scattering and scanning electron microscopy techniques. Transmission electron microscopy and electron diffraction studies of single-standing nanotubes revealed the presence of nanocrystalline titanium oxide phases with oxidation states lower than +4 (TiO, Ti2O3). Several assumptions on growth and self-organization mechanism of nanotube arrays have been made. 相似文献
997.
998.
Fedorova Irina; Alvheim Anita R.; Hussein Nahed; Salem Norman Jr. 《Canadian Metallurgical Quarterly》2009,123(6):1218
Docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) may be biosynthesized from a precursor α-linolenic acid (LNA) or obtained preformed in the diet. Dams were fed four diets with different levels of the various n-3 fatty acids during pregnancy and lactation, and their offspring were weaned to the same diets: “n-3 Deficient,” containing (as % total fatty acids) 0.07% of LNA; “Low LNA” (0.4%); “High LNA” (4.8%); and a “DHA + EPA” diet, containing 0.4% of LNA, 2% DHA, and 2% EPA. Sensorimotor gating was measured by prepulse inhibition (PPI) of the acoustic startle response in C57Bl6 mice. The n-3 Deficient and Low LNA diets caused a substantial deficit in PPI compared to the DHA + EPA diet, whereas the High LNA diet induced a less pronounced, but significant reduction of PPI. These are the first data that demonstrate a deficit in sensorimotor gating in rodents caused by an inadequate amount of the n-3 fatty acids in the diet. Our results differentiate the effects of a High LNA diet from one with added EPA and DHA even though the difference in brain DHA content is only 12% between these dietary groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Sonja Ellen Lobo Francisco Henrique Lanna Wykrota Ana Carolina Marques Barbosa Oliveira Irina Kerkis Germán Bohorquez Mahecha Humberto José Alves 《Journal of materials science. Materials in medicine》2009,20(5):1137-1147
Biphasic bioceramics have been widely indicated for bone reconstruction; however, the real gain in bone mass due to the presence
of such biomaterials has not been established yet nor the advantages of its association with platelet concentrate. This study
aims at quantifying the volume of bone matrix, osteoblasts, osteocytes, blood vessels and adipose tissue after the application
of a biphasic bioceramics composed of 65% hydroxyapatite and 35% β-tricalcium phosphate. Critical-size bone defects were produced
in rabbit femora and reconstructed with bioceramics only, with bioceramics combined with platelet concentrate, with platelet
concentrate alone, and with no treatment (blood clot). The quantitative evaluation was performed on histological sections
using histomorphometry. Our data provide original evidence that consolidates the indication of bioceramics for clinical bone
loss reconstruction. The application of biphasic bioceramics alone led to major bone mass gain and was followed by its association
with platelet concentrate. On the other hand, platelet concentrate can contribute to the augmentation and maintenance of the
adipose tissue, representing a new field for future applications in plastic surgery. 相似文献
1000.
A new approach for design of organic electrochromic devices with inter-digitated electrode structure
Galit Bar Galit Strum Raz Gvishi Nina Larina Vladimir Lokshin Vladimir Khodorkovsky Larissa Grinis Arie Zaban Irina Kiryuschev 《Solar Energy Materials & Solar Cells》2009,93(12):2118-8
We present a new approach for design of organic electrochromic devices (ECD) with inter-digitated electrode (IDE) structure and three-electrode dynamic operation. The advantages of the IDE design include the ability to produce fast and homogenous color change over large areas. In addition, it enables fabrication of multi-color devices. Our method involves photolithographic etching of ITO followed by electrophoretic deposition (EPD) and mechanical compression of porous titania to produce finely patterned electrodes with high surface area. The titania layer is chemically modified by new stable and reversible electrochromic viologen derivatives involving phenylphosphonic acid anchoring moiety. The new device demonstrates reversible and strong color change from colorless to deep blue and yellow. 相似文献