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排序方式: 共有332条查询结果,搜索用时 15 毫秒
91.
Pattern Analysis and Applications - The paper introduces a modified version of a genetic algorithm with aggressive mutation (GAAM) called fGAAM (fast GAAM) that significantly decreases the time... 相似文献
92.
Izabela Kowalska 《材料科学与工程:中英文B版...》2014,(8):248-254
Pressure-driven membrane processes were investigated for the recovery of contaminated cleaning solutions (a single-phase detergent) emanating from a diary industry. The experiments were performed in a semi-pilot membrane installation in cross-flow regime. The filtration tests were carded out using tubular ceramic modules differing in cut-offvalue, with high resistance to chemical agents. The effect of long term filtration time and process conditions (transmembrane pressure, cross-flow velocity and temperature) on transport and separation properties of the modules was evaluated. The usefulness of ceramic modules for regeneration of a single-phase detergent for the purpose of its reuse in cleaning systems was revealed. The modules in a long-term filtration regime, due to their hydrophilic nature, were characterized by relatively low susceptibility to fouling. Rinsing modules with deionized water after filtration experiments helped significantly to restore their original permeability or cause even an increase of water flux in comparison with the stream of deionized water. The recovered spent detergent maintained its basic cleaning properties, i.e., high pH, high concentration of NaOH and low value of surface tension. Moreover, the ceramic modules showed high retention of specific milk components (protein and lactose) and organic matter expressed as chemical oxygen demand (COD). It has been shown that the transport and separation properties of the modules were dependent on the process parameters, such as transmembrane pressure, cross-flow velocity and temperature. 相似文献
93.
Vanesa Calvino-Casilda Elena Pérez-Mayoral Rosa M. Martín-Aranda Zuzanna Zienkiewicz Izabela Sobczak Maria Ziolek 《Topics in Catalysis》2010,53(3-4):179-186
The present paper discloses a new alternative method for the isomerization of eugenol to isoeugenol where mesoporous materials containing niobium are used as solid base catalysts, affording good yields of isomerized product and being environmentally friendly. Nb-containing MCM-41 mesoporous materials were modified with alkaline cations (Li, Na, K, Rb and Cs) and characterized by BET, FTIR, XRD, and UV–vis techniques. The prepared materials were tested in the isomerization of eugenol to isoeugenol by sonochemical and thermally-activated reactions. Li, Na, K, Rb, and Cs/NbMCM-41 catalysts are active catalyst for the preparation of isoeugenol, and selective to the trans-isomer. Rb/NbMCM-41 sample is the optimum catalysts for the reaction. This result is in accordance with the calculated basicity observed during the Knoevenagel probe reaction of basicity. Conversions around 90% are obtained when using Rb-NbMCM-41 catalysts, with 90% selectivity to trans-isoeugenol, under ultrasound activation. In contrast, conversion around 72% with 90% selectivity is attained under classical thermal activation. The catalysts were reused four times without a substantial decrease of activity. 相似文献
94.
Monika Zarba-Kozio Anna Bartkowiak-Kaczmarek Matylda Roszkowska Krystian Bijata Izabela Figiel Anup Kumar Halder Paulina Kamiska Franziska E. Müller Subhadip Basu Weiqi Zhang Evgeni Ponimaskin Jakub Wodarczyk 《International journal of molecular sciences》2021,22(12)
Although sex differences in the brain are prevalent, the knowledge about mechanisms underlying sex-related effects on normal and pathological brain functioning is rather poor. It is known that female and male brains differ in size and connectivity. Moreover, those differences are related to neuronal morphology, synaptic plasticity, and molecular signaling pathways. Among different processes assuring proper synapse functions are posttranslational modifications, and among them, S-palmitoylation (S-PALM) emerges as a crucial mechanism regulating synaptic integrity. Protein S-PALM is governed by a family of palmitoyl acyltransferases, also known as DHHC proteins. Here we focused on the sex-related functional importance of DHHC7 acyltransferase because of its S-PALM action over different synaptic proteins as well as sex steroid receptors. Using the mass spectrometry-based PANIMoni method, we identified sex-dependent differences in the S-PALM of synaptic proteins potentially involved in the regulation of membrane excitability and synaptic transmission as well as in the signaling of proteins involved in the structural plasticity of dendritic spines. To determine a mechanistic source for obtained sex-dependent changes in protein S-PALM, we analyzed synaptoneurosomes isolated from DHHC7-/- (DHHC7KO) female and male mice. Our data showed sex-dependent action of DHHC7 acyltransferase. Furthermore, we revealed that different S-PALM proteins control the same biological processes in male and female synapses. 相似文献
95.
Izabela Marcińska Ilona Czyczy?o-Mysza Edyta Skrzypek Maciej T. Grzesiak Franciszek Janowiak Maria Filek Micha? Dziurka Kinga Dziurka Piotr Waligórski Katarzyna Juzoń Katarzyna Cyganek Stanis?aw Grzesiak 《International journal of molecular sciences》2013,14(7):13171-13193
The aim of the study was to assess the role of salicylic acid (SA) and abscisic acid (ABA) in osmotic stress tolerance of wheat seedlings. This was accomplished by determining the impact of the acids applied exogenously on seedlings grown under osmotic stress in hydroponics. The investigation was unique in its comprehensiveness, examining changes under osmotic stress and other conditions, and testing a number of parameters simultaneously. In both drought susceptible (SQ1) and drought resistant (CS) wheat cultivars, significant physiological and biochemical changes were observed upon the addition of SA (0.05 mM) or ABA (0.1 μM) to solutions containing half-strength Hoagland medium and PEG 6000 (−0.75 MPa). The most noticeable result of supplementing SA or ABA to the medium (PEG + SA and PEG + ABA) was a decrease in the length of leaves and roots in both cultivars. While PEG treatment reduced gas exchange parameters, chlorophyll content in CS, and osmotic potential, and conversely, increased lipid peroxidation, soluble carbohydrates in SQ1, proline content in both cultivars and total antioxidants activity in SQ1, PEG + SA or PEG + ABA did not change the values of these parameters. Furthermore, PEG caused a two-fold increase of endogenous ABA content in SQ1 and a four-fold increase in CS. PEG + ABA increased endogenous ABA only in SQ1, whereas PEG + SA caused a greater increase of ABA content in both cultivars compared to PEG. In PEG-treated plants growing until the harvest, a greater decrease of yield components was observed in SQ1 than in CS. PEG + SA, and particularly PEG + ABA, caused a greater increase of these yield parameters in CS compared to SQ1. In conclusion, SA and ABA ameliorate, particularly in the tolerant wheat cultivar, the harmful effects and after effects of osmotic stress induced by PEG in hydroponics through better osmotic adjustment achieved by an increase in proline and carbohydrate content as well as by an increase in antioxidant activity. 相似文献
96.
N. Swaminathan Paul J. Kamenski Dane Morgan Izabela Szlufarska 《Acta Materialia》2010,58(8):2843-2853
Cascade simulations in single crystal and nanocrystalline SiC have been conducted in order to determine the role of grain boundaries and grain size on defect production during primary radiation damage. Cascades are performed with 4 and 10 keV silicon as the primary knock-on atom (PKA). Total defect production is found to increase with decreasing grain size, and this effect is shown to be due to increased production in grain boundaries and changing grain boundary volume fraction. In order to consider in-grain defect production, a new mapping methodology is developed to properly normalize in-grain defect production rates for nanocrystalline materials. It is shown that the presence of grain boundaries does not affect the total normalized in-grain defect production significantly (the changes are lower than ~20%) for the PKA energies considered. Defect production in the single grain containing the PKA is also studied and found to increase for smaller grain sizes. In particular, for smaller grain sizes the defect production decreases with increasing distance from the grain boundary while for larger grain sizes the presence of the grain boundaries has negligible effect on defect production. The results suggest that experimentally observed changes in radiation resistance of nanocrystalline materials may be due to long-term damage evolution rather than changes in defect production rates from primary damage. 相似文献
97.
Izabela M. Barszczewska‐Rybarek 《应用聚合物科学杂志》2012,123(3):1604-1611
In this work, infrared spectroscopy was used to characterize the degree of double bonds conversion (DC) in six series of poly(urethane‐dimethacrylate)s, derived from dicarbamates of oligoethylene glycols monomethacrylates and aliphatic, cycloaliphatic and aromatic diisocyanates. To evaluate the degree of conversion in polymers devoid of aromatic moieties, two methods of calculation have been proposed: internal band ratio method, with carbonyl stretching vibrations as a standard, and a method involving the direct observation of the decrease in the intensity of C?C stretching band. The validity of these methods has been checked on polymers with aromatic structures, by comparing the results with those obtained by the internal band ratio method applying an aromatic band as a reference. A good correlation between the degree of conversion from two internal standard methods, using aromatic band and carbonyl band as references, was obtained. It was shown that the degree of conversion increases as the number of oxyethylene units increases. Polymerization of monomers with aliphatic cores resulted in higher DC values, while those with cycloaliphatic and aromatic cores—resulted in lower DC values. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
98.
Morpholinium-based ionic liquid mixtures as electrolytes in electrochemical double layer capacitors 总被引:1,自引:0,他引:1
Butyl-Methyl-Morpholinium bis(trifluoromethanesulphonyl)imide [ButMetMor][TFSI] and Ethyl-Methyl-Morpholinum bis(trifluoromethanesulphonyl)imide [EtMetMor][TFSI] and their mixtures with propylene carbonate (PC) were investigated as potential electrolytes in an electrochemical double layer capacitor (EDLC). Temperature dependencies of conductivity and electrochemical stability windows of ionic liquids (ILs) as well as their mixtures were determined. PC mixtures give higher conductivity with maximum ca. 1:4 (IL:PC) molar rate. Temperature dependencies of conductivity follow the Arrhenius type, showing higher energy activation for neat ILs rather than for mixtures. The EDLC was constructed based on activated carbon cloth (ACC, Kynol®) ca. 2000 m2 g?1 and IL:PC mixture giving specific capacitance of ca. 100–120 F g?1. 相似文献
99.
Kaminska I Das MR Coffinier Y Niedziolka-Jonsson J Sobczak J Woisel P Lyskawa J Opallo M Boukherroub R Szunerits S 《ACS applied materials & interfaces》2012,4(2):1016-1020
An easy and environmentally friendly chemical method for the simultaneous reduction and noncovalent functionalization of graphene oxide (GO) using dopamine derivatives is described. The reaction takes place at room temperature under ultrasonication of an aqueous suspension of GO and a dopamine derivative. X-ray photoelectron spectroscopy, FT-IR spectroscopy, and cyclic voltammetry characterizations revealed that the resulting material consists of graphene functionalized with the dopamine derivative. This one-step protocol is applied for simultaneous reduction and functionalization of graphene oxide with a dopamine derivative bearing an azide function. The chemical reactivity of the azide function was demonstrated by a postfunctionalization with ethynylferrocene using the Cu(I) catalyzed 1,3-dipolar cyloaddition. 相似文献
100.