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Understanding the uncertainty inherent in the analysis of diesel fuel consumption and its impact on the generation of electricity is an important topic for planning the expansion of isolated thermoelectric systems in the state of Amazonas. In light of this, a decision support system has been developed to forecast the cost of electricity production using non-stationary data by integrating the methodology of time series models with fuzzy systems and optimization tools. The method presented herein combines the potential of the Autoregressive Integrated Moving Average (ARIMA) and the Seasonal ARIMA (SARIMA) models, such as the forecasting tool, with the advantages of fuzzy set theory to compensate for the uncertainties and errors encountered in the observed data, which would degrade the validity of forecasted values. The results show that incorporation of the α-cut concept facilitated the evaluation of risks while allowing simultaneous consideration of intervals for the unitary cost of energy production. This provides the analyst with the ability to make decisions using various predicted intervals with different membership values instead of the common practice of simply using the specific costs. 相似文献
94.
Two‐step synthesis and properties of a magnetic‐field‐sensitive modified maltodextrin‐based hydrogel
Alexandre T Paulino André R Fajardo Andrea P Junior Edvani C Muniz Elias B Tambourgi 《Polymer International》2011,60(9):1324-1333
A magnetic‐field‐sensitive modified maltodextrin‐based hydrogel (ferrogel) was synthesized. Fourier transform infrared and 13C‐CP/MAS NMR spectral analyses confirmed the efficiency of the gelling process. X‐ray diffraction analysis revealed the appearance of new crystalline planes in the hydrogel diffractograms after embedding of magnetite nanoparticles. Magnetization curves and Mössbauer analysis revealed that the magnetic hydrogel has a high lattice strain due to bonded iron atom covalence. Moreover, some magnetite molecules embedded in the hydrogel ensure a degree of paramagnetism and iron atoms exhibiting oxidation states alternating between 2 and 3 in the final material. Scanning electron microscopy and energy‐dispersive X‐ray analysis revealed that no phase separation occurred between the magnetite nanoparticles and crosslinked hydrogel, indicating excellent dispersion throughout the hydrogel. Moreover, the average pore sizes decreased on increasing the amount of magnetite inside the polymer network. The results of compression stress versus strain revealed that the elasticity of the magnetic hydrogel was increased on increasing the amount of magnetite nanoparticles. Finally, kinetic studies revealed that the diffusion mechanism of water in the hydrogel is driven by anomalous release with a tendency towards the occurrence of macromolecular relaxation. Copyright © 2011 Society of Chemical Industry 相似文献
95.
Advanced performance evaluation of a reverse osmosis treatment for oilfield produced water aiming reuse 总被引:1,自引:0,他引:1
Marcel Melo Helga Schluter Jailton Ferreira Rosana Magda Agenor Júnior Oswaldo de Aquino 《Desalination》2010,250(3):1016-1018
Technology advancements and the increasing need for fresh water resources have created the potential for desalination of oil field brine (produced water) to be a cost-effective fresh water resource for beneficial reuse. At the mature oil and gas production areas in the northeast of Brazil, the majority of wells produce a substantial amount of water in comparison with oil production (more than 90%). At these fields, the produced water has to be treated on site only for oil and solids removal aiming re-injection. The aim of this work is to assess the quality of the produced water stream after a reverse osmosis desalination process in terms of physicochemical characteristics influencing reuse of the water for irrigation or other beneficial uses. 相似文献
96.
Aloe vera gel influence on the micellization behavior of copolymer Pluronic F127: A potential photosensitizer carrier for topical application 下载免费PDF全文
Luis Alberto Soto Dantas Silva Rafael Leone da Cruz de Jesus Raildo Alves Fiuza‐Junior Heloysa Martins Carvalho Andrade Isabel Cristina Rigoli Rosana Maria Nascimento de Assunção José Mario Barichello Renata Galvão de Lima 《应用聚合物科学杂志》2018,135(17)
This work describes the influence of aloe vera gel on Pluronic F127 triblock copolymer (F127) micellization behavior. Aloe vera gel was obtained from aloe vera mucilage found in leaf pulp. F127 (20% w/w) gel and the aloe vera/F127 blend gel were obtained by using the cold method. Fourier transform infrared spectroscopy and X‐ray diffraction analyses of lyophilized samples did not show any important copolymer interaction between aloe vera gel and F127. However, in aqueous medium, the dynamic light scattering data showed that there was an important reduction in micelle size with increasing temperature of the aloe vera/F127 blend hydrogel. The differential scanning calorimetry results indicate that the aloe vera/F127 blend has a higher micellization temperature, affected by the lower dehydrating effect of the poly(propylene oxide) blocks during the micelle formation in comparison to F127 gel. The texture analyses (hardness and adhesiveness) showed that the addition of aloe vera gel did not change the Pluronic F127 gel texture properties. The photosensitizer zinc phthalocyanine (ZnPC) was incorporated into the aloe vera/F127 blend, and the results suggest that this formulation is suitable as a ZnPC delivery system for photodynamic therapy. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46191. 相似文献
97.
Valdir Pereira Junior Priscila Lemes Rachadel Mara Novy Quadri Dachamir Hotza Sergio Yesid Gómez González 《Ceramics International》2018,44(17):20671-20676
High-performance perovskites are promising materials for diverse renewable energy technologies. Besides design characteristics, the devices performance depends on the material synthesis, since the processes occurring during synthesis may produce different structures and properties. In this work, the perovskite La0.1Sr0.9Co0.9Fe0.1O3-δ (LSCF1991) was synthesized by different methods, and the phase composition and oxygen deficiency were assessed and discussed. We show that it is possible to increase oxygen deficiency by promoting oxygen release during crystallization within hydrothermal synthesis, producing a remarkable improvement of ?δ ~0.2 in comparison with the citrate method. The single phase LSCF1991 powder was characterized, shaped by different routes and sintered to demonstrate the stability and suitability to manufacture electrochemical devices. 相似文献
98.
Xisto Antonio de Oliveira Neto Anna Carolina Schneider Alves Reinaldo Antonio Dias Junior Ricardo Pereira Rodrigues Marcelo Lancellotti Wanda Pereira Almeida Daniel Fbio Kawano 《European Journal of Lipid Science and Technology》2020,122(7)
Alkylphospholipids are synthetic analogues of endogenous phosphatidylcholines with a remarkable ability: induce the selective apoptosis of exponentially growing tumor cells. One hypothesis concerning their mechanism of action is the inhibition of cytidine triphosphate:phosphocholine cytidyltransferase (CCT), which would significantly suppress the phosphatidylcholine biosynthesis to trigger apoptosis. Herein, homology modeling, docking simulations, and the analyses of molecular interaction fields are used to suggest the most probable binding modes of four alkylphospholipids (edelfosine, erucylphosphocholine, perifosine, and miltefosine) and lysophosphatidylcholine at the catalytic domain of human CCT. All compounds display bind modes in agreement with the corresponding groups found in the CCT substrate, phosphocholine, while their binding strengths are increased because of the interaction of the alkyl chains with hydrophobic residues from the M domain of the protein. Analyses of the geometry of the CCT binding‐site also suggest that small groups, such as benzyl/2‐phenylethyl ethers or equivalent heterocycles, could replace the O‐methyl group in edelfosine to yield even better inhibitors. It is believed this study can guide the development of new alkylphospholipids with an improved profile for the inhibition of phosphatidylcholine biosynthesis, a critical component for cell cycle progression that can be explored in cancer chemotherapy. Practical Applications: Studies focusing on the interactions between small ligands and their protein targets are decisive for the comprehension of how conformational changes in the macromolecular structure dictates the biological activity and, consequently, how they can be explored in drug discovery. Most of the current studies on alkylphospholipids focuses on their physicochemical interactions with cholesterol and sphingolipids in lipid rafts that, because of the variability and complexity of the membrane phases, hardly can provide structural data in the X‐ray crystallography assays necessary for molecular modeling studies. Therefore, by exploring the inhibition of human cytidine triphosphate:phosphocholine cytidyltransferase as an alternative and, probably, complementary hypothesis to the membrane rafts, a helpful strategy can be provided to overcome the clinical limitations of alkylphospholipids. 相似文献
99.
Diniz João O. B. Quintanilha Darlan B. P. Santos Neto Antonino C. da Silva Giovanni L. F. Ferreira Jonnison L. Netto Stelmo M. B. Araújo José D. L. Da Cruz Luana B. Silva Thamila F. B. da S. Martins Caio M. Ferreira Marcos M. Rego Venicius G. Boaro José M. C. Cipriano Carolina L. S. Silva Aristófanes C. de Paiva Anselmo C. Junior Geraldo Braz de Almeida João D. S. Nunes Rodolfo A. Mogami Roberto Gattass M. 《Multimedia Tools and Applications》2021,80(19):29367-29399
Multimedia Tools and Applications - At the end of 2019, the World Health Organization (WHO) reported pneumonia that started in Wuhan, China, as a global emergency problem. Researchers quickly... 相似文献
100.
Giani Andrea Linde Antonio Laverde Junior Eliete Vaz de Faria Nelson Barros Colauto Flávio Faria de Moraes Gisella Maria Zanin 《Food research international (Ottawa, Ont.)》2010,43(1):187-192
This work fully demonstrated the formation of amino acids complexes with β-cyclodextrin (β-CD) by the method of nuclear magnetic resonance with the rotating frame Overhauser effect spectroscopy (ROESY) and diffusion ordered spectroscopy (DOSY) techniques. The tested amino acids display the following decreasing order of affinity for β-CD: tryptophane > tyrosine > phenylalanine > proline > histidine > isoleucine. The influence of complexation on taste perception was determined with a trained panel to qualify taste alterations of single amino acids and quantify the debittering of soy protein hydrolysate by β-CD complexation. The results showed that β-CD complexation is effective for modifying single amino acids taste perception and debittering soy protein hydrolysate. Bitterness sensation of the latter is reduced by 90% when 5% β-CD was added, thus β-CD is recommended as a prospective additive for masking bitter taste of new functional food products. 相似文献