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The abundance of Ca, its low redox potential and high specific capacity make Ca metal batteries an attractive energy storage system for the future. A recent demonstration of room temperature calcium plating/stripping opened a new avenue of the development, but the performance of cathode materials is lagging far behind. Due to the nature of divalent cations, conversion and coordination electrochemical reactions show better performance compared to insertion. Herein, we demonstrate the use of the anthraquinone‐based polymer as a cathode material for the Ca metal‐organic battery. Electrochemical mechanism investigation confirms the reversible reduction of the carbonyl bond and coordination with Ca2+ cations in the discharged state, opening a pathway toward high energy density battery. Continued performance of a 2‐electrode cell is strongly hampered by the overpotential increase caused by the Ca stripping process on the Ca metal anode stating the need for further development of Ca electrolytes. Ca metal‐organic battery promises to achieve cells with gravimetric energy density on the practical level compared to the state‐of‐the‐art Li‐ion batteries. [ABSTRACT FROM AUTHOR]

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Achieving optimal hydrophobicity of polymer materials especially polymer-matrix composites is important for many material applications. Herein the interplay of factors determining hydrophobic surface is presented during CF4 plasma treatments which lead to functionalization as well as selective polymer-matrix etching. The continuous exposure to plasma reactive species induces functionalization and etching on the surface, which decides the surface morphology and surface chemistry. Consequently, exothermic processes during the plasma-surface interactions are another important factor which influences the surface chemistry and etching rate of the material. The results demonstrate that despite etching and increasing surface roughness, the major contribution to hydrophobic character is dependent on the number of carbon atoms populated with fluorine, whereas the temperature is a deciding factor for type of created bonds. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Temperature and pH responsive microgel, based on poly-N-isopropylacrylamide and chitosan (PNCS) was studied, as possible carrier for antimicrobials on cotton fabric, to create smart stimuli responsive antimicrobial active textiles. Among antimicrobials 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (Si-QAC) and silver nanoparticles (AgNP) were chosen and applied to cotton fabric subsequently after the deposition of PNCS microgel. Influence of Si-QAC and AgNP on the swelling/deswelling activity of the PNCS microgel was obtained by temperature and pH responsiveness, along with determination of antimicrobial activity against Staphylococcus aureus and Escherichia coli. Even though Si-QAC slightly influenced swelling ability of the PNCS microgel and incorporation of AgNP reduced its amount on the surface of the fibres, PNCS microgel proved to be a suitable carrier of antimicrobial agents, thus imparting moisture management properties with effective controlled release of Si-QAC and AgNP. This provided excellent antimicrobial activity against tested bacteria, triggered by the change of temperature and pH of the surroundings. [ABSTRACT FROM AUTHOR]

Copyright of Tekstilec is the property of University of Ljubljana, Faculty of Natural Sciences & Engineering, Department of Textiles and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, we wish to report the preparation of ultra-black films via spraying coatings composed of waterborne binders and low-cost carbon aerogels on pre-treated tinplate. The CAs were prepared by annealing resorcinol-formaldehyde resin (RF resin) and the following CO2 activation, of which the reflectance was less than 0.4% in a wide wavelength range. The reflectance of different coatings, which using CAs as functional pigments, ranged from 1.8% to 4.3% in the visible light region (400−760 nm), while it ranged from 1.9% to 4.2% in the near-infrared region (760–1100 nm). Further studies revealed the relationship between the pigment-to-binder ratio and reflectance and found the best ratio to be 0.96, and the minimum reflection was less than 1.8%. Outstanding adhesion to the tinplate substrate was also achieved using a two-component polyurethane binder after the thermal cycling test carried out from −100 °C to 100 °C. The fabrication process of ultra-black coatings is particularly convenient to remove the constraints of high costs and complex processes, making it instructive guidance for industrial production. [ABSTRACT FROM AUTHOR]

Graphite-silver (AgC) composite materials are widely used in outdoor high-voltage electrical switchgear due to their combining properties of excellent conductivity and outstanding arc-suppressing performance. However, the methods for fabricating AgC composite materials still have some limitations. In this study, the cold spray technique was adopted to deposit AgC composite coatings with the optimized parameters on the copper substrate. Then, AgC coatings were annealed in the furnace and treated by laser scanning, respectively, to further improve the arc erosion resistance performance of the coatings. The results show that the phase structure and electrical resistance of AgC coatings were not influenced by the post-treatment process. Furthermore, excellent hydrophobic performance was obtained after surface laser scanning treatment. The laser scanning treatment exhibited favorable advantages in enhancing the arc erosion resistance of AgC coatings, which indicated the lowest arc erosion rate compared with the cold-sprayed and annealed coatings. [ABSTRACT FROM AUTHOR]

• ATR-FTIR spectroscopy offers affordable, fast and reliable sample characterization. • DNA analyses of skeletal remains depend on the sample's physicochemical structure. • DNA preservation depends on the state of mineral and collagen in skeletal remains. • Spectra contain enough information for a gross assessment of preserved DNA. • Chronological age of the sample highly impacts DNA preservation and predictions. Skeletal remains are commonly subjected to various analyses, including DNA. As the remains are exposed to taphonomic processes after the death of the organism, their physicochemical structure undergoes alterations. The success and integrity of a DNA analysis is thus conditioned by the preservation state of the sample. In this study, ATR-FTIR spectroscopy with further data exploration was employed to characterize the physicochemical structure of the samples and its correlation with the preservation state of the DNA. The aim was to test the hypothesis that ATR-FTIR–obtained spectra contain enough information to allow classification of the samples based on the preservation of the DNA in the remains. In the study, 138 human bones and teeth originating from the 16th century BC to the 21 st century AD were used. The samples were cleaned and powdered following the established methodological procedures for DNA extraction. DNA was extracted and quantified. The samples were separated into four categories based on the amount of quantified DNA. The remaining powder was analyzed with ATR-FTIR spectroscopy and the spectra obtained were explored to extract physicochemical information. Before the exploration of the acquired data, samples were divided into groups A (n = 107) and B (n = 31). Statistical analyses and machine learning were performed on the group A samples. The protocol was then validated on the group B samples, which served to make predictions on the preservation of the DNA in the remains. The best results were achieved using a random forest learning algorithm employing either normalized spectra, second-derivative spectra, or five highest-ranked ratios. Even though overlapping remained, these findings indicate that ATR-FTIR spectroscopy with further exploration of the data has good potential as a pre-screening method for evaluating DNA preservation in skeletal remains. [ABSTRACT FROM AUTHOR]

In healthcare facilities, infections caused by Staphylococcus aureus (S. aureus) from textile materials are a cause for concern, and nanomaterials are one of the solutions; however, their impact on safety and biocompatibility with the human body must not be neglected. This study aimed to develop a novel multilayer coating with poly(allylamine hydrochloride) (PAH) and immobilized ZnO nanoparticles (ZnO NPs) to make efficient antibacterial and biocompatible cotton, polyester, and nylon textiles. For this purpose, the coated textiles were characterized with profilometry, contact angles, and electrokinetic analyzer measurements. The ZnO NPs on the textiles were analyzed by scanning electron microscopy and inductively coupled plasma mass spectrometry. The antibacterial tests were conducted with S. aureus and biocompatibility with immortalized human keratinocyte cells. The results demonstrated successful PAH/ZnO coating formation on the textiles, demonstrating weak hydrophobic properties. Furthermore, PAH multilayers caused complete ZnO NP immobilization on the coated textiles. All coated textiles showed strong growth inhibition (2–3-log reduction) in planktonic and adhered S. aureus cells. The bacterial viability was reduced by more than 99%. Cotton, due to its better ZnO NP adherence, demonstrated a slightly higher antibacterial performance than polyester and nylon. The coating procedure enables the binding of ZnO NPs in an amount (<30 µg cm−2) that, after complete dissolution, is significantly below the concentration causing cytotoxicity (10 µg mL−1). [ABSTRACT FROM AUTHOR]

Freezing bone samples to preserve their biomolecular properties for various analyses at a later time is a common practice. Storage temperature and freeze–thaw cycles are well-known factors affecting degradation of molecules in the bone, whereas less is known about the form in which the tissue is most stable. In general, as little intervention as possible is advised before storage. In the case of DNA analyses, homogenization of the bone shortly before DNA extraction is recommended. Because recent research on the DNA yield from frozen bone fragments and frozen bone powder indicates better DNA preservation in the latter, the aim of the study presented here was to investigate and compare the chemical composition of both types of samples (fragments versus powder) using ATR-FTIR spectroscopy. Pairs of bone fragments and bone powder originating from the same femur of 57 individuals from a Second World War mass grave, stored in a freezer at − 20 °C for 10 years, were analyzed. Prior to analysis, the stored fragments were ground into powder, whereas the stored powder was analyzed without any further preparation. Spectroscopic analysis was performed using ATR-FTIR spectroscopy. The spectra obtained were processed and analyzed to determine and compare the chemical composition of both types of samples. The results show that frozen powdered samples have significantly better-preserved organic matter and lower concentrations of B-type carbonates, but higher concentrations of A-type carbonates and stoichiometric apatite. In addition, there are more differences in the samples with a low DNA degradation index and less in the samples with a high DNA degradation index. Because the results are inconsistent with the current understanding of bone preservation, additional research into optimal preparation and long-term storage of bone samples is necessary. [ABSTRACT FROM AUTHOR]

Polyamide 6 (PA6) composite filament yarns were produced by the simultaneous incorporation of melamine cyanurate (MeCy) with multiwalled carbon nanotubes (CNTs) and carbon black (CB) into a composite matrix in a melt‐spinning process. The results show that the simultaneous incorporation of MeCy with CNTs or CB additives provided filaments with a uniform black color. Tensile analysis confirmed that a reinforcing effect was achieved when CB was used, whereas the CNTs induced a reducing effect on the filament tenacity. With regard to the burning behavior, the flame‐retardant action of MeCy was preserved in the presence of CB but was significantly hindered when used in combination with CNTs. These results indicate that the mixture of MeCy and CB was much more compatible for the production of reinforced PA6 composite filaments with increased thermal stability and improved flame retardancy over those of the MeCy and CNTs. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47007. [ABSTRACT FROM AUTHOR]

Due to the rapid increase in the power conversion efficiency (PCE) of perovskite solar cells (PSCs) and approaching the theoretical maximum level in recent years, the main drawback of their future commercialization is to improve their long-term stability under existing environmental conditions. One of the problems with this technology lies in the absorbing layer, specifically the perovskite. In particular, when producing a perovskite film under ambient conditions, it is almost impossible to avoid film defects caused by environmental conditions (such as moisture, oxygen, and temperature), which could randomly change during the preparation process. Therefore, the fabrication of high-quality perovskite films is an urgent process that has a direct impact on the overall performance of the solar cells. The use of ionic liquids (ILs) as additives in perovskite precursor solutions is a promising strategy to improve not only the power conversion efficiency (PCE) but also the long-term stability of photovoltaic devices by controlling nucleation and crystal growth of perovskite film that avoids defects and produces high-quality perovskite layers. Here, the critical role of the ionic liquid 1-methyl-3-propylimidazolium iodide (1-MPII) in different perovskite precursor solutions such as MAPbI 3 (I), MAPbI 3 -PbBr 2 (B) and MAPbI 3 -PbCl 2 (CL) on carbon-based perovskite solar cells (C–PSCs) under ambient conditions is extensively studied. The results show that 1-MPII ionic liquid activates the surface morphology of all perovskite films and improves solar cells' efficiency due to the passivation of the uncoordinated Pb2+ defects. Furthermore, stability measurements show that the unencapsulated IL-modified devices for perovskites MAPbI 3 (IIL), MAPbI 3 -PbBr 2 (BIL), and MAPbI 3 -PbCl 2 (CLIL) retained at 84 %, 86 %, and 80 % of their original PCE for over 1100 h under ambient conditions with 45 % relative humidity (RH), compared to the IL-free PSCs. Moreover, the IL-modified PSCs exhibited an increased electrical performance ranging from 16.5 % to 33 % depending on the type of perovskite it was used, so that long-term stability also was reinforced. • 1-methyl-3-propylimidazolium iodide as additive to methyl ammonium-based perovskite semiconductors. • Improved electrical performance of PSCs with additive from 16.5 % to 33 % depending on the lead salt used. • Improved stability of unencapsulated PSCs with additive from 3 % to 10 % related to the perovskite type was used. [ABSTRACT FROM AUTHOR]

Pears are abundant in bioactive compounds, which exert favorable effects on human health. The biophysical attributes of fruit cuticles are pivotal in determining fruit quality, storability, and susceptibility to mold growth. This study aimed to elucidate the biophysical properties of six pear cultivars, 'Conference', 'Celina', 'Abate Fetel', 'Packham's Triumph', 'Sweet Sensation', and 'Williams'. Two maturity stages, unripe and fully ripened, were investigated. Furthermore, the efficacy of trimethyl-chitosan-coated pear surfaces in preventing Penicillium expansum (P. expansum) growth was assessed. Basic maturity indices (CIE color, ethylene evolution, firmness, soluble solids), cuticle contact angle, roughness, and zeta potential were analyzed. Surface roughness was measured using an optical profilometer, hydrophobicity was measured via profilometry, and zeta potential was quantified using an electrokinetic analyzer. The 'Celina' cultivar exhibited the highest roughness, whereas 'Williams' had the lowest roughness. All the cultivars' cuticles demonstrated hydrophilic characteristics, with contact angles ranging between 65° and 90°. For pH values exceeding 3.5, all pear surfaces exhibited a negative zeta potential. P. expansum growth was the slowest on the 'Packham's Triumph' and 'Conference' cultivars. Treatment with trimethyl chitosan effectively inhibited P. expansum growth in the initial hours of incubation. In conclusion, diverse pear cultivars manifest distinct biophysical surface properties and varying susceptibility to P. expansum growth. The growth of P. expansum correlates positively with roughness, contact angle, and zeta potential. These differences can significantly impact shelf life potential and the overall postharvest quality of pears. [ABSTRACT FROM AUTHOR]

ATR-FTIR spectroscopy is a fast and accessible, minimally or non-destructive technique which provides information on physiochemical characteristics of analyzed materials. In forensic and archaeological sciences, it is commonly used for answering numerous questions, including the archaeological or forensic context of the human skeletal remains. In this research, the accuracy of ATR-FTIR-obtained spectra for separation between forensic, WWII, and archaeological human skeletal remains was investigated. Building from the previously proposed methodological procedures, various ratio-based and whole spectra separation procedures were applied, carefully analyzed, and evaluated. Results showed that employing whole spectral domains works best for the separation of archaeological, WWII, and forensic samples, even with samples of highly variable origin. Principal component analysis (PCA) further highlighted the necessity of acknowledging all the major components in the remains: amides, phosphates, and carbonates for the separation. Most influential proved to be amide I, namely its secondary structure, which presented well-preserved and organized collagen structure in forensic and WWII samples, while highly degraded in archaeological samples. Using the whole spectral domain for separation between samples from different contexts proved to be fast and simple, with no manipulation beyond baseline correction and normalization of spectra necessary. However, a dataset with samples of known origin is required for the learning model and predictions. A less accurate alternative is separation based on combining ratios of peaks correlating to organics and minerals in the bone, which eliminated overlapping and managed to classify the majority of the samples correctly as archaeological, WWII, or forensic. [ABSTRACT FROM AUTHOR]

Shape, size, composition, and function of the bones in the human body vary on the macro, micro and nanoscale. This can influence changes caused by taphonomy and post-mortem preservation, including DNA. Highly mineralised compact bone is less susceptible to taphonomic factors than porous trabecular bone. Some studies imply that DNA can be better preserved in trabecular bone, due to remnants of the soft tissue or bacteria better digesting organic matter while not digesting DNA. The aim of this study was to understand the differences between compact (diaphyses) and trabecular (epiphyses) bone on a molecular level and thus the reasons for the better preservation of the DNA in the trabecular bone. The powder obtained from epiphyses and diaphyses of metacarpals and metatarsals was analysed using ATR-FTIR spectroscopy and compared. Samples with poorest DNA preservation originated from diaphyses, predominantly of metatarsals. They were characterised by higher concentrations of phosphates and crystallinity, while lower collagen quality in comparison to samples with the best DNA preservation. Epiphyses presented higher concentrations of better-preserved collagen while diaphyses had higher concentrations of carbonates and phosphates and higher crystallinity. Due to better-preserved collagen in the epiphyses, the soft tissue remnants hypothesis seems more likely than the bacteria hypothesis. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • PNCS micro- and nanogel were synthesised using the same monomer-to-monomer ratio. • In an aqueous dispersion, nanogel demonstrated greater swelling/de-swelling ability. • Particle size influenced the arrangement of hydrogels on the model PLA fibres. • Formation of a nanogel continuous layer on the PLA fibres hindered its volume change. • Handling properties were better preserved when using the smaller hydrogel particles. Abstract Hydrogels based on poly(N-isopropylacrylamide) (poly-NiPAAm) and chitosan (PNCS hydrogel) in two size ranges were synthesised, i.e. PNCS microgel (PNCS_M) and PNCS nanogel (PNCS_N) with an average particle size of 405 nm and 76 nm, respectively. Hydrogels were applied to poly(lactic acid) (PLA) fabric and the influence of the hydrogel particle size on the functional and handling properties of the fabric was assessed. Morphological and chemical changes were determined using FT-IR, SEM and AFM. The temperature and pH responsiveness of the functionalised PLA were studied based on the water uptake (WU), moisture content (MC) and water vapour transition rate (WVTR); thus, the rate of the liquid spreading through the sample and the overall stiffness of the padded samples were assessed. Both hydrogels improved air and moisture management of the functionalised PLA fabric. In an aqueous dispersion, PNCS_N demonstrated a greater volume change than PNCS_M. Particle size did not influence the LCST of poly-NiPAAm, but it affected morphology of the coated fibres. PNCS_M formed microgel particles on the PLA fibres, and a homogenous layer was observed on the PNCS_N coated fibres. Such deposition hindered swelling of the PNCS_N in comparison to the PNCS_M. The handling properties were better preserved when using smaller particles. [ABSTRACT FROM AUTHOR]