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Xi Yao Stuart S. Dunn Philseok Kim Meredith Duffy Jack Alvarenga Joanna Aizenberg 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(17):4507-4511
Omniphobic fluorogel elastomers were prepared by photocuring perfluorinated acrylates and a perfluoropolyether crosslinker. By tuning either the chemical composition or the temperature that control the crystallinity of the resulting polymer chains, a broad range of optical and mechanical properties of the fluorogel can be achieved. After infusing with fluorinated lubricants, the fluorogels showed excellent resistance to wetting by various liquids and anti‐biofouling behavior, while maintaining cytocompatiblity. 相似文献
54.
Green synthesis and antibacterial effects of aqueous colloidal solutions of silver nanoparticles using clove eugenol 下载免费PDF全文
Magdalena Parlinska‐Wojtan Joanna Depciuch Bartosz Fryc Małgorzata Kus‐Liskiewicz 《应用有机金属化学》2018,32(4)
Silver nanoparticles were synthesized using clove extract (CE). Scanning transmission electron microscopy (STEM) revealed the morphology of the metallic Ag nanoparticles obtained via the clove extract synthesis (Ag NPs‐CE), which had a uniform distribution and average sizes varying from 10 nm to 100 nm. Fourier transform infra‐red (FTIR) spectroscopy showed that clove eugenol acts as a capping and reducing agent being adsorbed on the surface of Ag NPs‐CE, enabling their reduction from Ag+ and preventing their agglomeration. Formation of the Ag0 structure is also confirmed in the FTIR spectrum by the presence in the Ag NPs‐CE sample of the –C=O and –C=C vibrations at wavenumbers 1600 and 2915 cm‐1, respectively. Antibacterial and antifungal tests using three strains of bacteria and one fungi strain showed that the Ag NPs‐CE performed better compared to pure clove extract (CE) sample. 相似文献
55.
The liquid‐crystalline polymorphism of the homologous series of 4‐hexyloxybenzylidene‐4′‐alkyloxyanilines is investigated. Basing on the polarization microscopy (POM, TOA), the DSC calorimetry and miscibility studies the following mesophases were detected: nematic, smectic A, smectic C and smectic I. The phase diagrams of the compounds of these series with 4‐hexyloxybenylidene‐4′‐pentylaniline (as the standard of mesophases) show induction of the smectic F mesophases. Their dependence on the alkyl chain length and mole fraction is shown. 相似文献
56.
Ryszard Krzyminiewski Bernadeta Dobosz Grzegorz Schroeder Joanna Kurczewska 《Physics letters. A》2018,382(44):3192-3196
The paper shows the application of a new method – Magnetic Nanoparticles Focusing 3D, MNF-3D – for focusing of magnetic nanoparticles at any point in a three-dimensional space between the rotating magnet system. The results of focusing process of nanoparticles in water, human blood, human serum and polyurethane sponge are presented. Additionally, blood flow was also considered. The effectiveness of nanoparticle focusing was monitored optically and quantitatively by electron spin resonance method. The method enabled focusing of magnetic nanoparticles within a few minutes in different environments. A good efficiency of focusing process was observed for all the samples. 相似文献
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Korać Jelena Todorović Nina Zakrzewska Joanna Žižić Milan Spasojević Ivan 《Structural chemistry》2018,29(5):1533-1541
Structural Chemistry - Epinephrine (Epi) is a physiologically important catecholamine. Molecular conformation of Epi controls the interactions with other molecules and its biological effects. There... 相似文献
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Karolina Wieszczycka Agata Gorzelańczyk Joanna Zembrzuska 《Research on Chemical Intermediates》2013,39(3):853-868
Photodegradation of the oximes of alkyl-2-, -3-, and -4-pyridylketones and identification of possible degradation products using LC–MS/MS and GC–MS techniques were performed. The influence of copper(II) and iron(III) ions on the stability of the oxime under UV–Vis radiation exposure were also studied. It was found that the photodegradation of the pyridylketoximes resulted in the photoisomerization, photofragmentation and photosubstitution to a pyridine ring. Based on these results, a hypothetical mechanism of photodegradation of pyridylketoximes was proposed. 相似文献
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Joanna Augustynowicz Anna M. Ko?ton Agnieszka M. Baran Anna M. Kostecka-Guga?a Wojciech W. Lasek 《Central European Journal of Chemistry》2013,11(2):295-303
The present work focused on the qualitative and quantitative analysis of Cr detoxification strategy of aquatic cosmopolitan plant Callitriche cophocarpa. This plant species has just been described in the context of its unusual accumulation potential of Cr. The emphasis of the work was placed on the redox reaction Cr(VI)→Cr(III) which is considered to be remediation mechanism of highly reactive and mobile Cr(VI) ions. Plants were immersed for 5 days in 1 mM of Cr(VI) (potassium dichromate) or 1 mM of Cr(III) (chromium sulphate) solutions in semi-natural conditions. Cr was effectively removed from the solution up to the extent of ca.58% or 35% of the starting amount, in the case of Cr(III) and Cr(VI), respectively. No plant-induced Cr(VI) reduction accompanying Cr accumulation was observed in Cr(VI) solutions except from the apparent one, noticed at the fourth day of incubation. On the contrary to these results, according to the method of electron paramagnetic resonance spectroscopy (L-band EPR), biphasic signal of Cr(V) attending Cr(VI) to Cr(III) reduction was detected inside the plant tissue every day of investigations. Our results show that phytoextraction but not phytostabilization is the main strategy of Cr detoxification by C. cophocarpa in aquatic systems. 相似文献