Renewable, Biomass-Derived, Honeycomblike Aerogel As a Robust Oil Absorbent with Two-Way Reusability

The disposal of oily wastewater has attracted extensive attention worldwide these days. Emerging environmentally friendly materials with large capacity and high selectivity that can effectively absorb oil and organic solvents from water or realize oil/water separation are in high demand. Herein, we demonstrated the facile fabrication of a sustainable, ecofriendly, biomass-derived, honeycomblike aerogel, taking lignin, agarose, and poly­(vinyl alcohol) (PVA) as basic ingredients. The aerogel possessed porous three-dimensional (3D) cellular structure with tunable low density (ρ < 0.052 g cm^–3) and featured good flexibility and compressibility. The modified aerogel, which was able to achieve switching from the absorption of oil and organic solvents to desorption just by altering the medium pH, was obtained simply through immersing the original aerogel into a solution of the synthesized copolymer containing pH-responsive component poly­(2-(dimethyl­amino)­ethyl methacrylate) (pDMAEMA). The absorption capacity of the modified aerogel for oil and organic solvents was in the range of 20–40 times its own weight, which was also adjustable via controlling the concentration of starting materials. The reusability of the modified aerogel could be carried out by both manual squeezing and pH-induced desorption, further broadening its application fields. The successful design of the biomass-derived modified aerogel with two-way reusability could provide new thoughts for the design of multifunctional oil absorbents, also giving efficient and sustainable options for water treatment and environmental protection

Molecular Design and Property Prediction of High Density Polynitro[3.3.3]-Propellane-Derivatized Frameworks as Potential High Explosives

Research in energetic materials is now heavily focused on the design and synthesis of novel insensitive high explosives (IHEs) for specialized applications. As an effective and time-saving tool for screening potential explosive structures, computer simulation has been widely used for the prediction of detonation properties of energetic molecules with relatively high precision. In this work, a series of new polynitrotetraoxopentaaza[3.3.3]-propellane molecules with tricyclic structures were designed. Their properties as potential high explosives including density, heats of formation, detonation properties, impact sensitivity, etc., have been extensively evaluated using volume-based thermodynamic calculations and density functional theory (DFT).These new energetic molecules exhibit high densities of >1.82 g cm^–3, in which <b>1</b> gives the highest density of 2.04 g cm^–3. Moreover, most new materials show good detonation properties and acceptable impact sensitivities, in which <b>5</b> displays much higher detonation velocity (9482 m s^–1) and pressure (43.9 GPa) than HMX and has a <i>h</i>₅₀ value of 11 cm. These results are expected to facilitate the experimental synthesis of new-generation nitramine-based high explosives

Renewable, Biomass-Derived, Honeycomblike Aerogel As a Robust Oil Absorbent with Two-Way Reusability

The disposal of oily wastewater has attracted extensive attention worldwide these days. Emerging environmentally friendly materials with large capacity and high selectivity that can effectively absorb oil and organic solvents from water or realize oil/water separation are in high demand. Herein, we demonstrated the facile fabrication of a sustainable, ecofriendly, biomass-derived, honeycomblike aerogel, taking lignin, agarose, and poly­(vinyl alcohol) (PVA) as basic ingredients. The aerogel possessed porous three-dimensional (3D) cellular structure with tunable low density (ρ < 0.052 g cm^–3) and featured good flexibility and compressibility. The modified aerogel, which was able to achieve switching from the absorption of oil and organic solvents to desorption just by altering the medium pH, was obtained simply through immersing the original aerogel into a solution of the synthesized copolymer containing pH-responsive component poly­(2-(dimethyl­amino)­ethyl methacrylate) (pDMAEMA). The absorption capacity of the modified aerogel for oil and organic solvents was in the range of 20–40 times its own weight, which was also adjustable via controlling the concentration of starting materials. The reusability of the modified aerogel could be carried out by both manual squeezing and pH-induced desorption, further broadening its application fields. The successful design of the biomass-derived modified aerogel with two-way reusability could provide new thoughts for the design of multifunctional oil absorbents, also giving efficient and sustainable options for water treatment and environmental protection

Oriented Arrays of Polyaniline Nanorods Grown on Graphite Nanosheets for an Electrochemical Supercapacitor

Oriented arrays of polyaniline (PANI) nanorods grown on expanded graphite (EG) nanosheets are fabricated by in situ polymerization to achieve excellent electrochemical properties for applications as supercapacitor electrodes. EG serves as an excellent 3D conductive skeleton that supports a highly electrolytic accessible surface area of redox-active PANI and provides a direct path for electrons. The porous and ordered nanostructure provides a larger contact surface area for the intercalation/deintercalation of protons into/out of active materials and shortens the path length for electrolyte ion transport. The maximum specific capacitance of 1665 F g^–1 at 1 A g^–1 is observed in the PANI/EG electrode with 10% EG content. The composite electrode material also exhibits significant rate capability and good long-term cycling stability. The results demonstrate that PANI is effectively utilized with the assistance of EG conductive skeletons in the electrode. Such 3D composite nanoarchitecture is very promising for the next generation of high-performance electrochemical supercapacitors

Silicone Oil-Infused Slippery Surfaces Based on Sol–Gel Process-Induced Nanocomposite Coatings: A Facile Approach to Highly Stable Bioinspired Surface for Biofouling Resistance

Slippery liquid-infused surfaces (SLIPS) have aroused widespread attention due to their excellent liquid-repellency properties associated with broad applications in various fields. However, the complicated preparation processes and the vulnerable surface lubricant layers severely restrict the practical applications of SLIPS. In this work, robust transparent slippery hybrid coatings (SHCs) were easily fabricated by the infusion of sol–gel-derived nanocomposite coatings in silicone oils of varying viscosity. The prepared silicone oil-infused surfaces exhibited outstanding long-term slippery stability even under extreme operating conditions such as high shear rate, elevated evaporation, and flowing aqueous immersion. Static bacteria culture tests confirmed that the SHCs could significantly inhibit biofilm formation. In addition, bovine serum albumin adhesion experiments were conducted after lubricant loss tests, showing significantly less protein absorption and a long service life of the SLIPS. The unique ultralow bacterial attachment and remarkably long-term protein-resistant performance render the as-prepared SLIPS as a promising candidate for biomedical applications even under harsh environmental conditions

Silicone Oil-Infused Slippery Surfaces Based on Sol–Gel Process-Induced Nanocomposite Coatings: A Facile Approach to Highly Stable Bioinspired Surface for Biofouling Resistance

Slippery liquid-infused surfaces (SLIPS) have aroused widespread attention due to their excellent liquid-repellency properties associated with broad applications in various fields. However, the complicated preparation processes and the vulnerable surface lubricant layers severely restrict the practical applications of SLIPS. In this work, robust transparent slippery hybrid coatings (SHCs) were easily fabricated by the infusion of sol–gel-derived nanocomposite coatings in silicone oils of varying viscosity. The prepared silicone oil-infused surfaces exhibited outstanding long-term slippery stability even under extreme operating conditions such as high shear rate, elevated evaporation, and flowing aqueous immersion. Static bacteria culture tests confirmed that the SHCs could significantly inhibit biofilm formation. In addition, bovine serum albumin adhesion experiments were conducted after lubricant loss tests, showing significantly less protein absorption and a long service life of the SLIPS. The unique ultralow bacterial attachment and remarkably long-term protein-resistant performance render the as-prepared SLIPS as a promising candidate for biomedical applications even under harsh environmental conditions

Effect of the sampling process upon a LH level signal with regular increasing sampling frequency.

<p>Case E (left panels): the pulse amplitude remains almost constant and the basal line increases regularly. Case F (right panels): the pulse amplitude decreases regularly and the basal line decreases regularly. Panels on row 1 represent the fine step simulation of LH blood level. Histograms on row 2 display the distribution of the LH pulse amplitudes and the distribution of the levels at the basal line, measured from the two theoretical LH level signals shown in row 1. A zoom on the distribution of the pulse amplitudes is shown as an insert in case E. Panels on row 3 represent the time series (blue stars) along the theoretical continuously measured LH level (green curve). Panels on row 4 represent the resulting LH measured time series (measured LH levels versus sampling times linked with segments). In both cases E and F, the sampling period is <i>Ts</i> = 10 min. In case E, the initial sampling time occurs at the first minute of the simulation (<i>r</i> = 1 min), without any variability in the sampling times (<i>f</i> = 0 min) or the assays (<i>b</i> = 0%). In case F, the initial sampling time occurs at the fourth minute of the simulation (<i>r</i> = 4 min), with variability both in the sampling times (<i>f</i> = 2 min) and the assays (<i>b</i> = 5%). Histograms on row 5 display the distribution of the LH pulse amplitudes and the distribution of the LH levels at the basal line, measured from the time series shown in row 4. While the distributions are regular in the theoretical time series, they become completely irregular in the sampled time series. As a result, the range of amplitudes is shortened. Regarding the distribution of the levels at the basal line, it is worth noticing that the measured values (E: between 0.125 and 0.519 ng/ml; F: between 0.094 and 0.258 ng/ml) are greater than the theoretical values (E: between 0.098 and 0.434 ng/ml; F: between 0.075 and 0.171 ng/ml). On the contrary, in case E, it is worth noticing that the theoretical pulse amplitudes vary from 2.379 to 2.425 ng/ml whereas measured pulse amplitudes vary from 1.447 to 2.395 ng/ml. In case F, all measured pulse amplitudes (between 0.302 and 1.959 ng/ml) are lower than the corresponding theoretical values (between 0.353 and 2.315 ng/ml).</p

Impact of Positional Isomerism on Melting Point and Stability in New Energetic Melt-Castable Materials

For an energetic material with a definite composition, the substituent position is the most crucial factor to influence its physicochemical properties. Thus, it is becoming increasingly important to understand the impact of positional isomerism on multidimensional properties differences. Herein, we reported two new potential energetic melt-castable molecules, a pair of positional isomers (4-MMDNP and 5-MMDNP). These two explosives exhibit obviously different properties, including densities (Δρ = 0.03 g cm–3), melting point (ΔTm = 47.2 °C), decomposition temperature (ΔTd = 27.3 °C), stability (IS = 20 J, FS = 160 N vs IS = 10 J, FS = 40 N), etc., even though they share similar compositions and structures. Simultaneously, by analyzing crystal packing, intermolecular interactions, and monomolecular parameters, we were able to uncover the roots of property differences. Altogether, our results provide comprehensive molecular and crystal level insight into the effect of positional isomerism, which may be useful for new molecular design

Impact of Positional Isomerism on Melting Point and Stability in New Energetic Melt-Castable Materials

For an energetic material with a definite composition, the substituent position is the most crucial factor to influence its physicochemical properties. Thus, it is becoming increasingly important to understand the impact of positional isomerism on multidimensional properties differences. Herein, we reported two new potential energetic melt-castable molecules, a pair of positional isomers (4-MMDNP and 5-MMDNP). These two explosives exhibit obviously different properties, including densities (Δρ = 0.03 g cm–3), melting point (ΔTm = 47.2 °C), decomposition temperature (ΔTd = 27.3 °C), stability (IS = 20 J, FS = 160 N vs IS = 10 J, FS = 40 N), etc., even though they share similar compositions and structures. Simultaneously, by analyzing crystal packing, intermolecular interactions, and monomolecular parameters, we were able to uncover the roots of property differences. Altogether, our results provide comprehensive molecular and crystal level insight into the effect of positional isomerism, which may be useful for new molecular design

Polyols-Infused Slippery Surfaces Based on Magnetic Fe₃O₄‑Functionalized Polymer Hybrids for Enhanced Multifunctional Anti-Icing and Deicing Properties

High durability, low cost, and superior anti-icing and active deicing multifunctional surface coatings, especially in the extreme environment, are highly desired to inhibit and/or eliminate the detriment of icing in many fields, such as automobile, aerospace, and power transmission. Herein, we first report a facile and versatile strategy to prepare novel slippery polyols-infused porous surfaces (SPIPS’s) with the inexpensive polyols as the lubricant liquids. These SPIPS’s are fabricated by a spray-coating approach based on amino-modified magnetic Fe₃O₄ nanoparticles (MNP@NH₂) and amphiphilic P­(poly­(ethylene glycol) methyl ether methacrylate-<i>co</i>-glycidyl methacrylate) copolymer covalent cross-linked hybrids, followed by infusion with various polyols. The as-prepared surface exhibits excellent antifrosting property, that is, it can greatly postpone frost formation as long as 2700 s at −18 °C. Meanwhile, differential scanning calorimetry results clearly demonstrate that SPIPS’s show a remarkable freezing point depression capacity and the crystallization point of water can be decreased as low as −36.8 °C. The SPIPS also displays an extremely low ice adhesion strength (0.1 kPa) due to its unique surface characteristics. Moreover, outstanding active thermal deicing property is achieved for these slippery surfaces because of intrinsically photothermal effect of magnetic Fe₃O₄ nanoparticle. Hence, these results indicate that this kind of multifunctional bioinspired slippery surface, with superb stability, good cost effectiveness, and easy fabrication, can be used as a promising candidate for anti-icing and deicing applications