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51.
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Maximilian Moser Tania Cecilia Hidalgo Jokubas Surgailis Johannes Gladisch Sarbani Ghosh Rajendar Sheelamanthula Quentin Thiburce Alexander Giovannitti Alberto Salleo Nicola Gasparini Andrew Wadsworth Igor Zozoulenko Magnus Berggren Eleni Stavrinidou Sahika Inal Iain McCulloch 《Advanced materials (Deerfield Beach, Fla.)》2020,32(37):2002748
A series of glycolated polythiophenes for use in organic electrochemical transistors (OECTs) is designed and synthesized, differing in the distribution of their ethylene glycol chains that are tethered to the conjugated backbone. While side chain redistribution does not have a significant impact on the optoelectronic properties of the polymers, this molecular engineering strategy strongly impacts the water uptake achieved in the polymers. By careful optimization of the water uptake in the polymer films, OECTs with unprecedented steady-state performances in terms of [μC*] and current retentions up to 98% over 700 electrochemical switching cycles are developed. 相似文献
53.
Zafar M. Abbas Tania Shakil M. Gillani S. S. A. Rizwan M. Arshad Hafsa Ahmed Shabbir 《Journal of Superconductivity and Novel Magnetism》2022,35(1):223-234
Journal of Superconductivity and Novel Magnetism - In this work, full potential linearized augmented plane wave (FP-LAPW) method is used to determine the electronic, magnetic, and mechanical... 相似文献
54.
Synthesis and Evaluation of a Series of Bis(pentylpyridinium) Compounds as Antifungal Agents 下载免费PDF全文
Dr. Daniel Obando Dr. Yasuko Koda Namfon Pantarat Dr. Sophie Lev Dr. Xiaoming Zuo Johanes Bijosono Oei Dr. Fred Widmer Prof. Julianne T. Djordjevic Prof. Tania C. Sorrell Prof. Katrina A. Jolliffe 《ChemMedChem》2018,13(14):1421-1436
A series of bis(4‐pentylpyridinium) compounds with a variety of spacers between the pyridinium headgroups was synthesised, and the antifungal activity of these compounds was investigated. Lengthening the alkyl spacer between the pentylpyridinium headgroups from 12 to 16 methylene units resulted in increased antifungal activity against C. neoformans and C. albicans, but also resulted in increased hemolytic activity and cytotoxicity against mammalian cells. However, inclusion of an ortho‐substituted benzene ring in the centre of the alkyl spacer resulted in decreased cytotoxicity and hemolytic activity, while maintaining antifungal potency. Replacement of the alkyl and aromatic‐containing spacers by more hydrophilic ethylene glycol groups resulted in a loss of antifungal activity. Some of the compounds inhibited fungal PLB1 activity, but the low correlation of this inhibition with antifungal potency indicates PLB1 inhibition is unlikely to be the predominant mode of antifungal action of this class of compounds, with preliminary studies suggesting they may act via disruption of fungal mitochondrial function. 相似文献
55.
Metal Organic Framework Crystals in Mixed‐Matrix Membranes: Impact of the Filler Morphology on the Gas Separation Performance 下载免费PDF全文
Anahid Sabetghadam Beatriz Seoane Damla Keskin Nicole Duim Tania Rodenas Salman Shahid Sara Sorribas Clément Le Guillouzer Guillaume Clet Carlos Tellez Marco Daturi Joaquin Coronas Freek Kapteijn Jorge Gascon 《Advanced functional materials》2016,26(18):3154-3163
Mixed‐matrix membranes comprising NH2‐MIL‐53(Al) and Matrimid or 6FDA‐DAM have been investigated. The metal organic framework (MOF) loading has been varied between 5 and 20 wt%, while NH2‐MIL‐53(Al) with three different morphologies, nanoparticles, nanorods, and microneedles has been dispersed in Matrimid. The synthesized membranes have been tested in the separation of CO2 from CH4 in an equimolar mixture. At 3 bar and 298 K for 8 wt% MOF loading, incorporation of NH2‐MIL‐53(Al) nanoparticles leads to the largest improvement compared to nanorods and microneedles. The incorporation of the best performing filler, i.e., NH2‐MIL‐53(Al) nanoparticles, into the highly permeable 6FDA‐DAM has a larger effect, and the CO2 permeability increases up to 85% with slightly lower selectivities for 20 wt% MOF loading. Specifically, these membranes have a permeability of 660 Barrer with a CO2/CH4 separation factor of 28, leading to a performance very close to the Robeson limit of 2008. Furthermore, a new non‐destructive technique based on Raman spectroscopy mapping is introduced to assess the homogeneity of the filler dispersion in the polymer matrix. The MOF contribution can be calculated by modeling the spectra. The determined homogeneity of the MOF filler distribution in the polymer is confirmed by focused ion beam scanning electron microscopy analysis. 相似文献
56.
Paez-Rubio T Ramarui A Sommer J Xin H Anderson J Peccia J 《Environmental science & technology》2007,41(10):3537-3544
This study measured aerosol emission rates produced during the spreading of dewatered class B biosolids onto agricultural land. Rates were determined in multiple independent experimental runs by characterizing both the source aerosol plume geometry and aerosol concentrations of PM10, total bacteria, heterotrophic plate count bacteria (HPC), two types of biosolids indicator bacteria, endotoxin, and airborne biosolids regulated metals. These components were also measured in the bulk biosolids to allow for correlating bulk biosolids concentrations with aerosol emission rates and to produce reconstructed aerosol concentrations. The average emission rates and associated standard deviation for biosolids PM10, total bacteria, HPC, total coliforms, sulfite-reducing Clostridia, endotoxin, and total biosolids regulated metals were 10.1 +/- 8.0 (mg/s), 1.98 +/- 1.41 x 10(9) (no./s), 9.0 +/- 11.2 x 10(7) (CFU/s), 4.9 +/- 2.2 x 10(3) (CFU/ s), 6.8 +/- 3.8 x 10(3) (CFU/s), 2.1 +/- 1.8 x 10(4) (EU/s), and 36.9 +/- 31.8 (microg/s) respectively. Based on the land application rates of spreaders used in this study, an estimated 7.6 +/- 6.3 mg of biosolids were aerosolized for every 1 kg (dry weight) applied to land. Scanning electron microscopy particle size distribution analysis of the aerosols revealed that greater than 99% of the emitted particles were less than 10 microm and particle size distributions had geometric mean diameters and standard deviations near 1.1 +/- 0.97 microm. The demonstrated correlations of bulk biosolids concentrations with aerosol emission rates, and the reconstruction of aerosol concentration based on PM10 and bulk biosolids concentration provide a more fundamental, bulk biosolids-based approach for extending biosolids aerosol exposure assessment to different land application scenarios and a broader range of toxins and pathogens. 相似文献
57.
We report the growth of horizontally aligned arrays and networks of GaN nanowires (NWs) as resonant components in nanoelectromechanical systems (NEMS). A combination of top-down selective area growth (SAG) and bottom-up vapor-liquid-solid (VLS) synthesis enables flexible fabrication of highly ordered nanowire arrays in situ with no postgrowth dispersion. Mechanical resonance of free-standing nanowires are measured, with quality factors (Q) ranging from 400 to 1000. We obtained a Young's modulus (E) of approximately 338 GPa from an array of NWs with varying diameters and lengths. The measurement allows detection of nanowire motion with a rotating frame and reveals dual fundamental resonant modes in two orthogonal planes. A universal ratio between the resonant frequencies of these two fundamental modes, irrespective of their dimensions, is observed and attributed to an isosceles cross section of GaN NWs. 相似文献
58.
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Tiago Bender Wermuth Mario Norberto Baibich Tania Maria Hubert Ribeiro Carlos Pérez Bergmann 《Ceramics International》2018,44(5):4758-4765
We studied the molar ratio effects of niobium and potassium precursors on the structure and morphology of potassium niobate powders prepared via microwave-assisted hydrothermal synthesis (MaHS). KNbO3 nanostructures in the form of nanotowers and nanocubes were obtained at reduced synthesis times (30–240 min). The products were characterized via XRD, Raman spectroscopy, SEM, and TEM; band gap calculations used diffuse reflectance data. The results indicate that KNbO3 nanostructures were obtained with crystallite sizes ranging from 33 to 52 nm. An orthorhombic crystalline structure was formed from the increase of KOH at a molar ratio Nb2O5:KOH (1:8 to 1:16 M). The band-gap of 3.1–3.3 eV has potential use in photodegradation applications. 相似文献