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1.
Michalis Koutinas Ludmila G Peeva Andrew G Livingston 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2005,80(11):1252-1260
This study presents a comparison of the efficiency of a bioscrubber and a biotrickling filter (BTF) for the removal of ethyl acetate (EA) vapour from a waste gas stream, under the same operating conditions. The maximum EA elimination capacity achieved in the bioscrubber was 550 g m?3 h?1 with removal efficiency higher than 96%. For higher EA loadings the bioscrubber was oxygen limited, which caused incomplete EA biodegradation. When pure oxygen was fed to the bioscrubber at a rate of 0.02 L min?1, the bioscrubber recovered and could treat higher EA loadings without any oxygen limitation. The BTF achieved EA elimination capacity of 600 g m?3 h?1 with removal efficiency higher than 97% and the dissolved oxygen concentration remained substantially higher than in the bioscrubber. However, severe channelling and blockage of the spray nozzle occurred due to the excessive biomass growth. Overall, the bioscrubber system was easier to operate and control than the BTF, while an enhancement of the oxygen mass transfer in the bioscrubber could potentially increase its performance by up to three times. Copyright © 2005 Society of Chemical Industry 相似文献
2.
The free energies of mixing of two networks in the interpenetrating polymer network based on crosslinked polyurethane and poly(ester acrylate) have been determined by the vapour sorption method. It was established that the constituent networks in the IPN are not miscible. The introduction of fillers of different chemical nature increases the compatibility. The thermodynamic affinity of the fillers to the individual networks and IPN was estimated. It was established that when the free energy of interaction of one or both components of the IPN with the filler is negative, reinforcement leads to the formation of a compatible and equilibrium system. For fillers having no affinity to the polymers, compatibilization is observed, which is connected with slowing down of phase separation in the system in the presence of filler. 相似文献
3.
Rowan Paul J.; Cofta-Woerpel Ludmila; Mazas Carlos A.; Vidrine Jennifer Irvin; Reitzel Lorraine R.; Cinciripini Paul M.; Wetter David W. 《Canadian Metallurgical Quarterly》2007,15(4):382
Ecological momentary assessment (EMA) consists of assessing phenomena in real time in the natural environment. EMA allows for more fine-grained analyses of addictive behavior and minimizes threats to internal validity, such as recall biases and errors. However, because of the intensive monitoring involved in EMA, measurement reactivity is a concern. To test whether EMA with palmtop personal computers induces reactivity, the authors compared smoking-related outcomes between smokers using EMA and those not using EMA during a quit attempt. The use of no-EMA control groups has been rare in reactivity investigations to date. The EMA protocol included event-contingent assessments (smoking episodes, urge episodes) and random assessments. Outcomes included biologically confirmed abstinence and self-report measures of withdrawal, self-efficacy, motivation, affect, and temptations. Participants were smokers motivated to quit (N = 96). They were randomized to 1 of 3 groups: EMA for the week preceding a planned quit date, EMA for the week following the quit date, and no EMA. Abstinence rates did not differ between the groups at Day 7 or at Day 28 postcessation. For the 20 subscales assessed at each of 3 assessment times, there were significant differences between participants with and without EMA experience for 3 subscales at the 1st of 3 assessment times, and significant differences for 3 different subscales at the 3rd assessment time. These differences suggest some reactivity to EMA, although the inconsistent pattern across time indicates that further research is needed to definitively conclude that EMA induces reactivity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Xin Shen Rui Zhang Shuhao Wang Xiang Chen Chuan Zhao Elena Kuzmina Elena Karaseva Vladimir Kolosnitsyn Qiang Zhang 《中国化学工程学报》2021,37(9):137-143
Lithium (Li) metal anodes promise an ultrahigh theoretical energy density and low redox potential,thus being the critical energy material for next-generation batteries.Unfortunately,the formation of Li den-drites in Li metal anodes remarkably hinders the practical applications of Li metal anodes.Herein,the dynamic evolution of discrete Li dendrites and aggregated Li dendrites with increasing current densities is visualized by in-situ optical microscopy in conjunction with ex-situ scanning electron microscopy.As revealed by the phase field simulations,the formation of aggregated Li dendrites under high current den-sity is attributed to the locally concentrated electric field rather than the depletion of Li ions.More specif-ically,the locally concentrated electric field stems from the spatial inhomogeneity on the Li metal surface and will be further enhanced with increasing current densities.Adjusting the above two factors with the help of the constructed phase field model is able to regulate the electrodeposited morphology from aggregated Li dendrites to discrete Li dendrites,and ultimately columnar Li morphology.The methodol-ogy and mechanistic understanding established herein give a significant step toward the practical appli-cations of Li metal anodes. 相似文献
5.
Federico Karp Florencia S. Satler Carlos A. Busatto Julio A. Luna Diana A. Estenoz Ludmila N. Turino 《应用聚合物科学杂志》2021,138(17):50293
The aim of the present work is the characterization of PLGA microparticles including biopolymers for the controlled release of tilmicosin, a broad-spectrum antibiotic. Microparticles were prepared using the double-emulsion solvent evaporation technique. The effect of alginate and pectin incorporation over particle size and porosity, encapsulation efficiency (EE) and pH-responsive drug release was evaluated. Formulations presented a mean particle size of 5.5 μm approximately and a drug EE ranged from 22%–57%. PLGA-Alginate particles showed an increased porosity. Tilmicosin release profiles from PLGA and PLGA-biopolymer microparticles were affected by the particular combination of polymers and the pH of the release medium. The experimental data was simulated using a mathematical model, which takes into account the autocatalytic polymer degradation and the different mechanisms of drug transport. The combination of PLGA and biopolymers strongly influenced the morphology of the particles, offering the possibility of controlling the drug release profiles according to the therapy. 相似文献
6.
An oscillatory network model with controllable coupling and self-organized synchronization-based performance was developed
for image processing. The model demonstrates the following capabilities: (a) brightness segmentation of real grey-level images;
(b) colored image segmentation; (c) selective image segmentation—extraction of the subset of image fragments with brightness
values contained in an arbitrary given interval. An additional capability—successive selection of spatially separated fragments
of a visual scene—has been achieved via further model extension. The fragment selection (under minor natural restrictions
on mutual fragment locations) is based on in-phase internal synchronization of oscillator ensembles, corresponding to all
the fragments, and distinct phase shifts between different ensembles. 相似文献
7.
8.
Sergey O. Bachurin Elena F. Shevtsova Galina F. Makhaeva Alexey Yu. Aksinenko Vladimir V. Grigoriev Tatiana V. Goreva Tatiana A. Epishina Nadezhda V. Kovaleva Natalia P. Boltneva Sofya V. Lushchekina Elena V. Rudakova Darya V. Vinogradova Pavel N. Shevtsov Elena A. Pushkareva Ludmila G. Dubova Tatiana P. Serkova Ivan M. Veselov Vladimir P. Fisenko Rudy J. Richardson 《International journal of molecular sciences》2022,23(22)
The development of multi-target-directed ligands (MTDLs) would provide effective therapy of neurodegenerative diseases (ND) with complex and nonclear pathogenesis. A promising method to create such potential drugs is combining neuroactive pharmacophoric groups acting on different biotargets involved in the pathogenesis of ND. We developed a synthetic algorithm for the conjugation of indole derivatives and methylene blue (MB), which are pharmacophoric ligands that act on the key stages of pathogenesis. We synthesized hybrid structures and performed a comprehensive screening for a specific set of biotargets participating in the pathogenesis of ND (i.e., cholinesterases, NMDA receptor, mitochondria, and microtubules assembly). The results of the screening study enabled us to find two lead compounds (4h and 4i) which effectively inhibited cholinesterases and bound to the AChE PAS, possessed antioxidant activity, and stimulated the assembly of microtubules. One of them (4i) exhibited activity as a ligand for the ifenprodil-specific site of the NMDA receptor. In addition, this lead compound was able to bypass the inhibition of complex I and prevent calcium-induced mitochondrial depolarization, suggesting a neuroprotective property that was confirmed using a cellular calcium overload model of neurodegeneration. Thus, these new MB-cycloalkaneindole conjugates constitute a promising class of compounds for the development of multitarget neuroprotective drugs which simultaneously act on several targets, thereby providing cognitive stimulating, neuroprotective, and disease-modifying effects. 相似文献
9.
Vitamin D is no longer considered an agent only affecting calcium phosphate metabolism. A number of studies over the past few years have demonstrated its role in immunomodulation and its influence on the development and functioning of the brain and nervous system. In the current epidemiological crisis caused by coronavirus disease 2019 (COVID-19), the immunoprotective role of vitamin D has been discussed by some authors regarding whether it contributes to protection against this serious disease or whether its use does not play a role. Non-standard approaches taken by laboratories in examining the serum levels of the vitamin D metabolite calcidiol have contributed to inconsistent results. We examined the serum of 60 volunteers in the spring and autumn of 2021 who declared whether they were taking vitamin D at the time of sampling. Furthermore, the tested participants noted whether they had experienced COVID-19. A newly developed liquid chromatography–tandem mass spectrometry (LC-MS/MS) method was used to measure calcidiol levels. The analysis of variance (ANOVA) model of Statgraphics Centurion 18 statistical software from Statgraphics Technologies was used for calculations. The results of this study showed that those who took vitamin D suffered significantly less often from COVID-19 than those who did not take vitamin D. 相似文献
10.
Anna Siskova Jan Kral Jana Drabova Klara Cervena Kristyna Tomasova Jiri Jungwirth Tomas Hucl Pavel Kohout Sandra Summerova Ludmila Vodickova Pavel Vodicka Veronika Vymetalkova 《International journal of molecular sciences》2022,23(14)
A colorectal adenoma, an aberrantly growing tissue, arises from the intestinal epithelium and is considered as precursor of colorectal cancer (CRC). In this study, we investigated structural and numerical chromosomal aberrations in adenomas, hypothesizing that chromosomal instability (CIN) occurs early in adenomas. We applied array comparative genomic hybridization (aCGH) to fresh frozen colorectal adenomas and their adjacent mucosa from 16 patients who underwent colonoscopy examination. In our study, histologically similar colorectal adenomas showed wide variability in chromosomal instability. Based on the obtained results, we further stratified patients into four distinct groups. The first group showed the gain of MALAT1 and TALAM1, long non-coding RNAs (lncRNAs). The second group involved patients with numerous microdeletions. The third group consisted of patients with a disrupted karyotype. The fourth group of patients did not show any CIN in adenomas. Overall, we identified frequent losses in genes, such as TSC2, COL1A1, NOTCH1, MIR4673, and GNAS, and gene gain containing MALAT1 and TALAM1. Since long non-coding RNA MALAT1 is associated with cancer cell metastasis and migration, its gene amplification represents an important event for adenoma development. 相似文献