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Efficient recovery of accidentally spilled viscous crude oil remains a global challenge, due to its poor fluidity at low temperature. Advanced porous absorbent with self-heating capability using multi-energy heating is highly desirable to mitigate the threat of oil spills to marine environment. Herein, photothermal nano-candle soot (CS), magneto thermal nano-Fe 3 O 4 , and polydimethylsiloxane (PDMS) with low surface energy were incorporated into an aligned porous microchannel structure of thermoplastic polyurethane (TPU) sponge. This endowed the sponge with robust mechanical compressibility, superhydrophobicity/superoleophilicity, and remarkable photo/magneto-thermal properties. The temperature of PDMS-CS/Fe 3 O 4 @TPU sponge surface could be rapidly heated to 87.7 ℃ under simulated sunlight of 1.0 kW m−2 intensity, and to 105.8 ℃ in an alternating magnetic field of H = 5 kA m−1. Notably, the temperature of the composite sponge surface reached 87.6 ℃ with the combination of weak sunlight irradiation of 0.5 kW m−2 and alternating magnetic field (AMF) intensity of 3 kA m−1. Furthermore, the composite sponge could achieve continuous recovery of viscous crude oil at a rate up to 503.5 kg m−2 h−1 with the combination of weak sunlight irradiation and AMF. This work reports a prospective strategy and material for efficient and all-weather recovery of spilled viscous crude oil. [Display omitted] • TPU sponge functionalized by Fe 3 O 4 and candle soot nanoparticles was successfully prepared. • Capillary forces in the aligned channel-like structure enhance the crude oil sorption rate. • The PDMS-CS/Fe 3 O 4 @TPU sponge displays excellent photo/magneto-thermal performance. • The PDMS-CS/Fe 3 O 4 @TPU sponge can achieve multiple energies-assisted recovery of viscous crude oil in all weather conditions. • The PDMS-CS/Fe 3 O 4 @TPU sponge could continuously recover viscous crude oil from water. [ABSTRACT FROM AUTHOR]

As a valuable biomass resource, a large number of Chinese medicine residue have not been effectively utilized and are often treated as garbage, which not only causes environmental pollution, but also leads to the waste of resources. Ganoderma lucidum is a common raw material of Chinese herbal medicine, its natural mycelium and tube structure is conducive to the formation the porous structure of carbon materials. In this paper, porous carbon materials with high specific surface area and high pore volume were prepared by high temperature carbonization in nitrogen atmosphere using Ganoderma lucidum residue as a raw material and KOH as an alkali activator. The morphology and pore structure of the prepared carbon materials were analyzed and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction, Raman spectroscopy and nitrogen adsorption method. When the mass ratio of carbon to alkali was 1:4 and the temperature was 800 °C, ultra-high specific surface area microporous carbon materials were obtained with specific surface area of 3425 m3 g−1 and total pore volume of 1.74 cm3 g−1. The prepared porous carbon material was assembled into hydrogen peroxide electrode and cholesteric oxide modified electrode, which showed good catalytic performance. [Display omitted] • High added value utilization of Ganoderma lucidum residues was reported. • The mycelium and tube structure of Ganoderma lucidum are conducive to the high specific surface area of materials. • The morphology, structure and properties of the materials were characterized in detail. • The prepared carbon materials have good application potential in electrode materials. [ABSTRACT FROM AUTHOR]

Abstract: While it is widely known that coronal mass ejections and their related solar wind features are significant drivers of activity with geospace it is less known that corotating interaction regions (CIRs) and the high speed stream (HSS) periods that precede them are also drivers of activity within geospace. The most recent extended and weak solar minimum interval has brought renewed attention to the space weather impacts of CIR+HSS periods since the highly structured and relatively stable coronal hole features on the Sun resulted in numerous CIR+HSS periods. In this paper we examine two Carrington Rotations (CRs) using the Coupled Magnetosphere Ionosphere Thermosphere (CMIT) model. CR2060 lasted from August 14, 2007 to September 11, 2007 and contained three CIR+HSS periods. CR2068, also known as the Whole Heliosphere Interval (WHI), began on March 20, 2008 and lasted until April 16, 2008 and contained two CIR+HSS periods. For each CR simulations driven by both L1 solar wind observations from the OMNI data set and L1 conditions extracted from CORHEL heliospheric simulations were conducted. The heliospheric simulation results capture the velocity and density structures seen in the solar wind well for CR2060 and only get one of the CIR+HSS periods in CR2068. In each CR the heliospheric simulations produce a much weaker IMF and have less temporal variability in all parameters. We compare the results of the CMIT simulations for each CR to observations of the cross polar cap potential (CPCP), hemispheric power (HP), and index including the computation of RMS and cross correlation error metrics. We examine the response of the thermospheric density during these intervals by utilizing data from the CHAMP satellite. In the magnetosphere we use magnetic field data from the GOES spacecraft to asses the different simulations ability to describe the distribution and intensity the ULF wave power. Our results show that the L1 driven simulations under-estimates the index and HP and over-estimates the CPCP. We believe that over estimation of the CPCP is directly linked to the low HP highlighting the need for an improved precipitation model within CMIT. The ULF power in the L1 simulations compares well with the observations, especially for the compressional component important in radiation belt energization processes. In all cases, the CMIT simulations driven by the heliospheric simulation results produce dramatically inferior predictions highlighting the importance of having good IMF predictions in heliospheric model results and possibly indicating the importance of having fluctuations in the solar wind. [Copyright &y& Elsevier]

Abstract: The effect of carbon dioxide (CO2) cooling on trends of hmF 2 and NmF 2 are investigated using a coupled thermosphere and ionosphere general circulation model. Model simulations indicate that CO2 cooling not only causes contraction of the upper atmosphere and changes of neutral and ion composition but also changes dynamics and electrodynamics in the thermosphere/ionosphere. These changes determine the altitude dependence of ionospheric trends and complex latitudinal, longitudinal, diurnal, seasonal, and solar cycle variations of trends of hmF 2 and NmF 2. Under the CO2 cooling effect, trends of NmF 2 are negative with magnitude from 0% to ∼−40% for doubled CO2, depending on location, local time, season, and solar activity. The corresponding trends of hmF 2 are mostly negative with a magnitude from 0 to −40km, but can be positive with a magnitude from 0 to ∼10km at night, with maximum positive trends occurring after midnight under solar minimum conditions. [Copyright &y& Elsevier]

Abstract: Condensation polymerization was used in the preparation of modified guanidine polymers. The polymers were composed of hexamethylene diamine and guanidine hydrochloride with subsequent crosslinking of epichlorohydrin. The two-step synthesis method increased the molecular weight of guanidine polymers, and also enhanced the charge density of the polymer due to the formation of the four-membered rings containing quaternary ammonium groups. This was found to improve antimicrobial activity. The molecular structure of the prepared guanidine polymer was characterized by 2D heteronuclear correlation NMR spectroscopy (C–H COSY). Results indicated that guanidine polymer was a mixture with various structures. UV260 absorption and AFM were applied to reveal the dynamic antimicrobial process of guanidine polymer and morphological change of bacterial cells. Both UV260 absorption and AFM images showed that the antimicrobial mechanism of guanidine polymer was to destruct the cell membrane of bacteria and cause the leakage of intracellular components from bacterial cells. [Copyright &y& Elsevier]

Four alginate gels were prepared by in situ release of calcium cations from Ca-EDTA with gradual hydrolysis of d-glucono-δ-lactone (GDL) in 3 wt% of aqueous solutions of four alginate samples with different M/G compositions, molecular weights, and molecular weight distributions. The sol–gel transition was monitored by measuring the dynamic mechanical spectroscopy in the linear region with variation in the mole ratio f of Ca2+ to the carboxyl group in the alginate. fgel, the critical value of f at the gel point, was determined according to the appearance of power law relaxation for the storage and loss moduli as proposed by Winter and Chambon. The critical exponent of relaxation moduli n for the power law was estimated from the loss tangent tan δ=G″/G′ at the gel point which is independent of angular frequency. fgel for the two samples with higher M/G ratio is about 0.037 while that for the other two samples with lower M/G ratio is 0.049 and 0.060, suggesting that more Ca2+ cations are chelated into the ‘egg-box’ cavities formed by the G sequence to cross-link alginate chains with higher G content. The n value is higher than 0.5, showing that the Ca2+ induced alginate network is not perfect due to its low concentration. [Copyright &y& Elsevier]

Highlights: [•] Bilayer coating to achieve bifunctional paper for packaging. [•] Synergistic interaction to enhance each function. [•] Confocal laser scanning microscope to identify the presence of each coating layer and understand its role. [ABSTRACT FROM AUTHOR]

Abstract: The structural evolutions of the mechanically alloyed ternary Al70Cu20Fe10 powders with the milling time and the annealing treatment have been studied by X-ray diffraction (XRD), transmission electronic microscopy (TEM) and X-ray absorption fine-structure spectroscopy (XAFS) techniques. Results show that an Al2Cu compound forms with short-time milling, while a Cu9Al4 compound forms with long-time milling. Fe can react with Al–Cu alloy by annealing treatment. Al7Cu2Fe compound with tetragonal structure or Al (Cu, Fe) solid solution with cubic structure may form at lower temperature, while a quasicrystal phase of Al65Cu20Fe15 alloy may form at higher temperature. [Copyright &y& Elsevier]

Abstract: The wavelength dependence of solar irradiance enhancement during flare events is one of the important factors in determining how the Thermosphere–Ionosphere (T–I) system responds to flares. To investigate the wavelength dependence of flare enhancement, the Flare Irradiance Spectral Model (FISM) was run for 61 X-class flares. The absolute and the percentage increases of solar irradiance at flare peaks, compared to pre-flare conditions, have clear wavelength dependences. The 0–14nm irradiance increases much more (~680% on average) than that in the 14–25nm waveband (~65% on average), except at 24nm (~220%). The average percentage increases for the 25–105nm and 122–190nm wavebands are ~120% and ~35%, respectively. The influence of 6 different wavebands (0–14nm, 14–25nm, 25–105nm, 105–120nm, 121.56nm, and 122–175nm) on the thermosphere was examined for the October 28th, 2003 flare (X17-class) event by coupling FISM with the National Center for Atmospheric Research (NCAR) Thermosphere–Ionosphere-Electrodynamics General Circulation Model (TIE-GCM) under geomagnetically quiet conditions (Kp=1). While the enhancement in the 0–14nm waveband caused the largest enhancement of the globally integrated solar heating, the impact of solar irradiance enhancement on the thermosphere at 400km is largest for the 25–105nm waveband (EUV), which accounts for about 33K of the total 45K temperature enhancement, and ~7.4% of the total ~11.5% neutral density enhancement. The effect of 122–175nm flare radiation on the thermosphere is rather small. The study also illustrates that the high-altitude thermospheric response to the flare radiation at 0–175nm is almost a linear combination of the responses to the individual wavebands. The upper thermospheric temperature and density enhancements peaked 3–5h after the maximum flare radiation. [Copyright &y& Elsevier]

Abstract: Chitosan–guanidine complexes were prepared by reacting chitosan and polyhexamethylene guanidine hydrochloride or crosslinked polyhexamethylene guanidine hydrochloride in the presence of sodium tripolyphosphate as a crosslinking agent. The complexes, used as functional additives for paper, synergistically improved wet-strength and antimicrobial activities. In comparison with the control sample, the wet/dry strength ratio of hand-sheets treated with the complexes was increased from 2.65% up to 23.3%. The MIC values of the chitosan–PHGH and chitosan–PHGHE complexes against Escherichia coli were 15.6 and 31.2μgmL−1, respectively, thus demonstrating excellent antimicrobial activity. Hand-sheets treated with the complexes exhibited antibacterial activity against E. coli and Staphylococcus aureus. The release of the guanidine polymers included in the complexes was dynamically monitored using UV and the results showed the amount released exceeded 80%. Atomic force microscopy images indicated that the antimicrobial mechanism of the complexes was likely due to membrane damage. [Copyright &y& Elsevier]