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71.
Sylwia Matysiak Julia Zabielska Józef Kula Alina Kunicka-Styczyńska 《Journal of the American Oil Chemists' Society》2020,97(1):67-79
The growing role of fatty acid amides in medicinal chemistry has recently been observed. Therefore, using simple and fast methods, a series of chiral amide derivatives (24 compounds) of ricinoleic and 3-hydroxynonanoic acid was obtained with 31–95% yields. Then, the evaluation of their antimicrobial activity against 13 microorganisms representing Gram-positive and Gram-negative bacteria, yeast, and molds was performed. The obtained compounds showed antimold potential; however, the tested species of molds were more susceptible to derivatives of 3-hydroxynonanoic acid than to amides obtained from ricinoleic acid (RA). Interestingly, hydroxamic acids derived from RA exhibited the best activity against Candida albicans and Candida tropicalis. On the other hand, hydroxamic acids derived from 3-hydroxynonanoic acid showed the best antimicrobial potential against the remaining tested microorganisms, especially against Pseudomonas cedrina. The obtained derivatives can be considered compounds of potential pharmacological significance, which is important due to the increasing problem of microbial resistance. 相似文献
72.
A hybrid fluidized-bed bioreactor for water purification was proposed and analyzed. It is a novel type of bioreactor characterized by hitherto unknown stationary and dynamic features. Steady-state characteristics of this hybrid bioreactor with external liquid circulation are presented. A quantitative analysis of steady-state properties of the bioreactor was performed with the aid of an original mathematical model developed for a double-substrate aerobic microbiological process. A steady-state analysis of aerobic processes characterized by different oxygen demand was performed. The effect of essential parameters was evaluated, including carbonaceous substrate concentration in the feed stream to the apparatus, aeration intensity, total residence time of a liquid in the bioreactor, and height of the bed of fine carrier particles. 相似文献
73.
Alex Gansen Martin Řehoř Clemens Sill Patrycja Polińska Stephan Westermann Jean Dheur Jack S. Hale Jörg Baller 《应用聚合物科学杂志》2020,137(24):48806
An optical method allowing the characterization of melt flow instabilities typically occurring during an extrusion process of polymers and polymer compounds is presented. It is based on a camera-acquired image of the extruded compound with a reference length scale. Application of image processing and transformation of the calibrated image to the frequency domain yields the magnitude spectrum of the instability. The effectiveness of the before mentioned approach is shown on Styrene-butadiene rubber (SBR) compounds, covering a wide range of silica filler content, extruded through a Göttfert capillary rheometer. The results of the image-based analysis are compared with the results from the sharkskin option, a series of highly sensitive pressure transducers installed inside the rheometer. A simplified version of the code used to produce the optical analysis results is included as supplementary material. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48806. 相似文献
74.
Rajmund S. Dybczyński Marta Pyszynska Krzysztof Kulisa Anna Bojanowska-Czajka 《分离科学与技术》2020,55(7):1364-1379
ABSTRACTNew ion interaction chromatographic (IIC) method employing Kromasil 100 C18 column and tetra-n-butylammonium hydroxide (TBAOH) as an ion interaction reagent (IIR) is able to separate yttrium from Rare Earth Elements (REE) as anionic complexes with nitrilotriacetic acid (NTA). New method for the chromatographic determination of Y in REE mixture was devised and validated by the analysis of the certified reference material (CRM). Potential possibilities of the new chromatographic system for larger scale applications including macro-micro events were demonstrated. 相似文献
75.
Fly ash as a sorbent for boron removal from aqueous solutions: Equilibrium and thermodynamic studies
Justyna Ulatowska Izabela Polowczyk Anna Bastrzyk Tomasz Koźlecki Wojciech Sawiński 《分离科学与技术》2020,55(12):2149-2157
ABSTRACT This study presents the application of fly ash from brown coal and biomass burning power plant as a sorbent for the removal of boron ions from an aqueous solution. The adsorption process efficiency depended on the parameters, such as adsorbent dosage, pH, temperature, agitation time and initial boron concentration. The experimental data fitted well with the Freundlich isotherm model and the maximum capacity was found to be 16.14 mg g?1. The adsorption kinetics followed the pseudo-second-order model. Also, the intra-particle diffusion model parameters were calculated. Thermodynamic parameters such as change in free energy (ΔG°), enthalpy (ΔH°), entropy (ΔS°) revealed on exothermic nature of boron adsorption onto the fly ash. 相似文献
76.
A Kuczyńska A Kosmala M Surma T Adamski 《International journal of molecular sciences》2012,13(8):10410-10423
Barley (Hordeum vulgare L.) is an important cereal crop grown for both the feed and malting industries. The allelic dwarfing gene sdw1/denso has been used throughout the world to develop commercial barley varieties. Proteomic analysis offers a new approach to identify a broad spectrum of genes that are expressed in the living system. Two-dimensional electrophoresis and mass spectrometry were applied to investigate changes in protein abundance associated with different juvenile growth habit as effect of the denso locus in barley homozygous lines derived from a Maresi × Pomo cross combination. A total of 31 protein spots were revealed that demonstrate quantitative differences in protein abundance between the analyzed plants with different juvenile growth habit, and these protein spots were selected to be identified by mass spectrometry. Identification was successful for 27 spots, and functional annotations of proteins revealed that most of them are involved in metabolism and disease/defense-related processes. Functions of the identified proteins and their probable influence on the growth habit in barley are discussed. 相似文献
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