Mixed aquo-organic solvents are used in chemical, industrial, and pharmaceutical processes along with amphiphilic materials. Their fundamental studies with reference to bulk and interfacial phenomena ...are thus considered to be important, but such detailed studies are limited. In this work, the interfacial adsorption of sodium dodecylsulfate (SDS, C12H25SO4 –Na+) in dioxane–water (Dn–W) and methanol–water (Ml–W) media in extensive mixing ratios along with its bulk behavior have been investigated. The solvent-composition-dependent properties have been identified, and their quantifications have been attempted. The SDS micellization has been assessed in terms of different solvent parameters, and the possible formation of an ion pair and triple ion of the colloidal electrolyte, C12H25SO4 –Na+ in the Dn–W medium has been correlated and quantified. In the Ml–W medium at a high volume percent of Ml, the SDS amphiphile formed special associated species instead of ion association. The formation of self-assembly and the energetics of SDS in the mixed solvent media have been determined and assessed using conductometry, calorimetry, tensiometry, viscometry, NMR, and DLS methods. The detailed study undertaken herein with respect to the behavior of SDS in the mixed aquo-organic solvent media (Dn–W and Ml–W) is a new kind of endeavor.
The development of high‐density magnetic recording media is limited by superparamagnetism in very small ferromagnetic crystals. Hard magnetic materials with strong perpendicular anisotropy offer ...stability and high recording density. To overcome the difficulty of writing media with a large coercivity, heat‐assisted magnetic recording was developed, rapidly heating the media to the Curie temperature Tc before writing, followed by rapid cooling. Requirements are a suitable Tc, coupled with anisotropic thermal conductivity and hard magnetic properties. Here, Rh2CoSb is introduced as a new hard magnet with potential for thin‐film magnetic recording. A magnetocrystalline anisotropy of 3.6 MJ m−3 is combined with a saturation magnetization of μ0Ms = 0.52 T at 2 K (2.2 MJ m−3 and 0.44 T at room temperature). The magnetic hardness parameter of 3.7 at room temperature is the highest observed for any rare‐earth‐free hard magnet. The anisotropy is related to an unquenched orbital moment of 0.42 μB on Co, which is hybridized with neighboring Rh atoms with a large spin–orbit interaction. Moreover, the pronounced temperature dependence of the anisotropy that follows from its Tc of 450 K, together with a thermal conductivity of 20 W m−1 K−1, make Rh2CoSb a candidate for the development of heat‐assisted writing with a recording density in excess of 10 Tb in.−2.
Rh2CoSb is introduced as a potential hard magnet for heat‐assisted magnetic recording. The hardness parameter of 3.7 is the highest observed for any rare‐earth‐free hard magnet. The temperature dependence of the anisotropy, together with the high anisotropic thermal conductivity of 20 W m−1 K−1, makes Rh2CoSb a candidate for heat‐assisted writing with a high recording density.
Breath acetone (BrAC) detection presents a promising scheme for noninvasive monitoring of metabolic health due to its close correlation to diets and exercise-regulated lipolysis. Herein, we report a ...Ti3C2Tx MXene-based wireless facemask for on-body BrAC detection and real-time tracking of lipid metabolism, where Ti3C2Tx MXene serves as a versatile nanoplatform for not only acetone detection but also breath interference filtration. The incorporation of in situ grown TiO2 and short peptides with Ti3C2Tx MXene further improves the acetone sensitivity and selectivity, while TiO2-MXene interfaces facilitate light-assisted response calibration. To further realize wearable breath monitoring, a miniaturized flexible detection tag has been integrated with a commercially available facemask, which enables facile BrAC detection and wireless data transmission. Through the hierarchically designed filtration-detection-calibration-transmission system, we realize BrAC detection down to 0.31 ppm (part per million) in breath. On-body breath tests validate the facemask in dynamically monitoring of lipid metabolism, which could guide dieter, athletes, and fitness enthusiasts to arrange diets and exercise activities. The proposed wearable platform opens up new possibility toward the practice of breath analysis as well as daily lipid metabolic management.
A MXene-based wireless facemask is developed to automatically monitor breath acetone and indicate the lipid metabolism level influenced by diets and exercises. Basing on the evaluation of the hierarchically assembled MXene-decorated filter, MXene acetone sensor, and a detection tag, on-body tests are carried out to validate the facemask platform in real breath samples, which highlights its practice in daily healthcare. Display omitted
ABSTRACT
We report the phase-connected timing ephemeris, polarization pulse profiles, Faraday rotation measurements, and Rotating-Vector-Model (RVM) fitting results of 12 millisecond pulsars (MSPs) ...discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in the Commensal Radio Astronomy FAST survey (CRAFTS). The timing campaigns were carried out with FAST and Arecibo over 3 yr. 11 of the 12 pulsars are in neutron star–white dwarf binary systems, with orbital periods between 2.4 and 100 d. 10 of them have spin periods, companion masses, and orbital eccentricities that are consistent with the theoretical expectations for MSP–Helium white dwarf (He WD) systems. The last binary pulsar (PSR J1912−0952) has a significantly smaller spin frequency and a smaller companion mass, the latter could be caused by a low orbital inclination for the system. Its orbital period of 29 d is well within the range of orbital periods where some MSP–He WD systems have shown anomalous eccentricities, however, the eccentricity of PSR J1912−0952 is typical of what one finds for the remaining MSP–He WD systems.
Display omitted
•Thermodynamic parameters of Fe-based glasses hop as cNb rises from 7 to 10 at.%.•Passive ability of these glasses increases drastically as cNb rises from 7 to 10 at.%.•Netlike ...structure in these glasses associated with Fe23B6 cell is verified with simulations.•Netlike structure explains the structure and passivation changes in these glasses.
The atomic structure and corrosion behavior of Fe87-xB13Nbx (x = 0, 7, 10 and 13) metallic glasses were investigated using various experimental techniques and simulations. The netlike (Fe, Nb)23B6 structure units, which took root in the Nb-contained amorphous matrix, emerged after annealing and raised markedly corrosion resistance of as-spun amorphous samples as cNb > 7 at.%, such as the occurrence of wider passive platform in the potentiodynamic polarization plots and the transformation from the porous holes to stable passive films on corrosion surfaces.
ABSTRACT
We report the follow-up of 10 pulsars discovered by the Five-hundred-metre Aperture Spherical radio-Telescope (FAST) during its commissioning. The pulsars were discovered at a frequency of ...500-MHz using the ultrawide-band (UWB) receiver in drift-scan mode, as part of the Commensal Radio Astronomy FAST Survey (CRAFTS). We carried out the timing campaign with the 100-m Effelsberg radio-telescope at L-band around 1.36 GHz. Along with 11 FAST pulsars previously reported, FAST seems to be uncovering a population of older pulsars, bordering and/or even across the pulsar death-lines. We report here two sources with notable characteristics. PSR J1951+4724 is a young and energetic pulsar with nearly 100 per cent of linearly polarized flux density and visible up to an observing frequency of 8 GHz. PSR J2338+4818, a mildly recycled pulsar in a 95.2-d orbit with a Carbon–Oxygen white dwarf (WD) companion of $\gtrsim 1\, \rm {M}_{\odot }$, based on estimates from the mass function. This system is the widest WD binary with the most massive companion known to-date. Conspicuous discrepancy was found between estimations based on NE2001 and YMW16 electron density models, which can be attributed to underrepresentation of pulsars in the sky region between Galactic longitudes 70° < l < 100°. This work represents one of the early CRAFTS results, which start to show potential to substantially enrich the pulsar sample and refine the Galactic electron density model.
Background and Aims
Bunch bagging is a grapevine canopy management strategy to protect bunches from light, heat stress and disease pressure. The aim of this study was to unveil the effects of timing ...and duration of bunch bagging on grape volatile organic compounds (VOCs) at the transcriptomic and metabolic levels.
Methods and Results
Seven bunch bagging treatments of varying timing and duration were implemented with Cabernet Sauvignon grapes. Regardless of timing and duration, bagging significantly reduced nerol, benzaldehyde, benzeneacetaldehyde and p‐cymene, and increased the concentration of phenol and 3,5‐dimethylbenzaldehyde. The decrease of nerol by bagging was associated with the down‐regulation of the gene encoding glycosyltransferase14 at veraison. Bagging and re‐exposing bunches at the preharvest stage inhibited and benefited the accumulation of C6 alcohols. Furthermore, we infer that the higher concentration of total benzenoids in all bagged berries was due to the down‐regulated expression of phenylpropanoid biosynthesis genes. The concentration of the dominant norisoprenoid, β‐damascenone, was not impacted by bunch bagging from veraison to harvest and was increased by bagging from veraison to post‐veraison. All other treatments, however, reduced this compound, which was due to a lower concentration of β‐carotene and lutein, and the down‐regulation of VviCCD4a and VviCCD4b.
Conclusions
Both timing and duration of bunch bagging can affect biosynthesis and accumulation of VOCs.
Significance of the Study
Insights from this study provide new knowledge on bunch bagging, as well as information regarding the sensitivity of VOCs to light and the timing of light exposure during grape ripening.
Ionic organic contaminants (OCs) are a growing concern for water treatment and the environment and are removed inefficiently by many existing technologies. This study examined removal of anionic OCs ...by anion exchange resins (AXRs) as a promising alternative. Results indicate that two polystyrene AXRs (IRA910 and IRA96) have higher sorption capacities and selectivity than a polyacrylate resin (A860). For the polystyrene resins, selectivity follows: phenolates ≥ aromatic dicarboxylates > aromatic monocarboxylates > benzenesulfonate > aliphatic carboxylates. This trend can be explained based on hydration energy, the number of exchange groups, and aromaticity and hydrophobicity of the nonpolar moiety (NPM) of the anions. For A860, selectivity only varies within a narrow range (0.13–1.64). Despite the importance of the NPM of the anions, neutral solutes were sorbed much less, indicating synergistic combinations of electrostatic and nonelectrostatic interactions in the overall sorption. By conducting multiple linear regression between Abraham’s descriptors and nature log of selectivity, induced dipole-related interactions and electrostatic interactions were found to be the most important interaction forces for sorption of the anions, while solute H-bond basicity has a negative effect. A predictive model was then developed for carboxylates and phenolates based on the poly parameter linear free energy relationships established for a diverse range of 16 anions and 5 neutral solutes, and was validated by accurate prediction of sorption of five test solutes within a wide range of equilibrium concentrations and that of benzoate at different pH.
Wood decomposition is a key process in the terrestrial carbon cycle, controlling carbon storage with feedback to climate. In (sub) tropical forest, termites are major players in wood decomposition, ...but their role relative to that of microbial decomposers and wood traits of different tree species is poorly understood. The current literature also has strong bias towards dicot tree decomposition, while abundant woody monocots, particularly bamboos, also contribute greatly to (sub) tropical carbon cycling. Here, we present the first experiment to disentangle effects of dead wood traits and termite activity on decomposition of 66 angiosperm species of wide‐ranging phylogenetic position: 31 bamboos, eight non‐bamboo Poaceae, 18 eudicots and nine magnoliids. We incubated dead stems of up to 4 size classes per species in a ‘common garden’ in tropical S China. We tested the hypotheses that (i) dead wood of bamboo (monocots) is less decomposable than dead wood of eudicots or magnoliids; (ii) both microbial‐ and termite‐driven decomposition show negative relationships with initial wood density and with dry matter content. Bamboo wood generally decomposed more slowly than dicot wood but only slightly slower at given wood density or diameter. Wood decomposition in both bamboo and dicot clades decreased with wood density or dry matter content. Termites contributed greatly to this pattern, explaining 53.4% of the variance in wood decomposition and preferentially attacking dead wood of lower initial density, which corresponded with thicker outer culm walls in the case of bamboo species. Thus, termites strongly strengthen the relationship between species' wood traits and litter decomposition as driven by microbial activity. Synthesis. These previously unknown relationships among dead wood quality, diameter, termites and decomposing microbes of both woody monocots and dicots will advance our understanding of the driving mechanisms of (sub) tropical wood decomposition and its contribution to the global carbon cycle.
Medicinal plants are considered to be a major source of biologically active compounds, which provides unlimited opportunities for their use either as medical treatments or as novel drug formulations.
...The focus of our study was on basic phytochemical analysis and in vitro examination of the biological activity of Alchemilla vulgaris L. Methanolic extracts of above ground parts and roots of A. vulgaris (AVA and AVR, respectively) were prepared by maceration for 72h. Phytochemical profile of extracts was evaluated by spectrophotometric determinations of phenolic compounds and HPLC-PDA analysis. AVA and AVR were analysed for their antioxidant efficacy as total antioxidant capacity, metal chelation and reducing power ability, inhibition of lipid peroxidation as well as their potential to neutralise DPPH, ABTS, and OH radicals. Microdilution method was employed to investigate the antibacterial and antifungal activity of extracts against nine ATCC and isolates of bacteria and ten fungal strains from biological samples. Anti-inflammatory activity of the extracts was evaluated using cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) assays and the assay for determination of COX-2 gene expression, while biocompatibility of extracts was assessed by MTT assay.
Our results revealed the high amount of phenolic compounds in both extracts; especially they were rich in condensed tannins. Ellagic acid and catechin were tentatively identified in AVA and AVR, respectively. Full biocompatibility as well as remarkable bioactivity were observed for both extracts in all employed assays, so our further investigations will be focused on the identification of active constituents in A. vulgaris and the molecular mechanisms of their action.
•A. vulgaris aerial parts and roots extracts were analysed.•Methanol extracts of aerial parts and roots were rich in phenolic compounds.•Ellagic acid was detected in aboveground parts and (+)-catechin in the roots.•Extracts showed remarkable antioxidant and anti-inflammatory activities.•Aerial parts extract exhibited better activity in all employed assays.
PDF
