SCG-Based CNF Aerogels with Oriented and Aligned Porous Structure for Solar Interfacial Desalination.

Spent coffee grounds are recognized as a green and sustainable resource of cellulose nanofiber (CNF), which can further form aerogels with rGO for solar-driven interfacial desalination via directional freezing technology. The vertically arranged channels provide better photothermal conversion performance and salt tolerance of rGO/CNF aerogels. Their max evaporation rate can reach to 2.729 kg·m-2·h-1 under natural sunlight. In terms of long-term application (10 days), the aerogels exhibit a stable evaporation property in outdoor environments. The optimum daily average water yield is 15.00 L·m-2, which can fulfill the daily water requirement of six people.

Interaction between m6A and ncRNAs and Its Association with Diseases.

Noncoding RNAs (ncRNA) are a kind of endogenous RNA that regulate many vital bioprocesses with limited ability to encode polypeptides. Most of them are involved in transcriptional and posttranscriptional regulations, thus showing some biological effects. N6-methyladenosine (m6A) RNA modification is a reversible modification that adjusts RNA's functions and stability. The enzymes that regulate m6A can be divided into "writers," "readers," and "erasers." Mechanically, m6A modification of microRNA is mainly identified by DGVR8, participating in the processing of primary micro-RNAs, while m6A modification on long noncoding RNA (lnc-RNA) can change its spatial structure and stability to regulate its RNA- or protein-binding ability. The m6A-modified lnc-RNA and circular RNA can act as competing endogenous RNAs, sponge downstream miRNA. Moreover, ncRNA can also regulate m6A level of downstream molecules. Here, we elaborate on recent advances about pathways and underlying molecular mechanisms of how the interaction between m6A and ncRNA is involved in the occurrence and development of various diseases, especially cancer.

Multifunctional Ti3C2Tx MXene/Low-Density Polyethylene Soft Robots with Programmable Configuration for Amphibious Motions.

To diversify the motion modes of multifunctional soft robots capable of shape programming, we fabricate a biomimetic and programmable Ti3C2Tx MXene/low-density polyethylene (LDPE) bilayer actuator by spraying an aqueous dispersion of MXenes onto a plasma-activated LDPE film, followed by optimal thermal regulations. Because of the eminent light absorption and photothermal/electrothermal features of MXenes and the extremely mismatched thermal expansion coefficients between the two layers, the MXene/LDPE actuator can be sensitively driven by many stimuli of near-infrared light, electricity, and heat. The initial configuration of the bilayer actuator can be programmed by tuning the thermal regulation temperature, thereby assembling multiple actuation units to achieve biomimetic functions, such as artificial iris, mechanical arms, and flying birds. More importantly, in virtue of free shape cutting and programmable configuration, the MXene/LDPE bilayer actuator can perform untethered locomotion including crawling, rolling, and sailing. The soft robots can not only move on the ground in different forms but also sail on water along any designated routes and complete the surface cargo transportation driven by a near-infrared laser via the photothermal Marangoni effect. The shape-programmable methodology for the three amphibious motion modes lays foundations for wide applications of the MXene-based soft robots.

CO2-Triggered ON/OFF Wettability Switching on Bioinspired Polylactic Acid Porous Films for Controllable Bioadhesion.

Bioinspired honeycomb-like porous films with switchable properties have drawn much attention recently owing to their potential application in scenarios in which the conversion between two opposite properties is required. Herein, the CO2-gas-triggered ON/OFF switching wettability of biocompatible polylactic acid (PLA) honeycomb porous films is fabricated. Highly ordered porous films with diameters between 2.0 and 2.8 µm are separately prepared from complexes of nonresponsive PLA and a CO2-sensitive melamine derivative [N2,N4,N6-tris(3-(dimethylamino)propyl)-1,3,5-triazine-2,4,6-triamine, MET] via the breath figure method. The hydrophilic CO2-sensitive groups can be precisely arranged in the pore's inner surface and/or top surface of the films by simply changing the PLA/MET ratio. The sensitive groups in the pore's inner surface act as a switch triggered by CO2 gas controlling water to enter the pores or not, thus resulting in ON/OFF switching wettability. The largest response of the water contact angle of honeycomb films reaches 35°, from 100 to 65°, leading to an obvious hydrophobic-hydrophilic conversion. The improved surface wettability enhances the interaction between the cell and honeycomb film surface, thus resulting in a better cell attachment. Such smart properties accompanying the biocompatible polymer and biological gas trigger facilitate possible biomedical and bioengineering applications in the future for these films.

Numerical and Experimental Investigation of Soot Suppression by Acoustic Oscillated Combustion.

The soot suppression by acoustic oscillations for acetylene diffusion flames was investigated combining numerical and experimental studies. The combustion and soot formation were predicted by the finite-rate detailed chemistry model and modified Moss-Brookes model, respectively, while the turbulence was predicted by the detached eddy simulation (DES) with a low Reynolds number correction. Experimental results showed that the soot rate almost decreased linearly with the amplitude of acoustic oscillation, and the pinch-off of the flame occurred at a large acoustic oscillation. Numerical results showed that the flame structure was well predicted, while the soot rate was over-predicted at large acoustic oscillations; the consumption of O2 increased obviously with the acoustic oscillation. The soot suppression was mainly caused by the decrease of the surface growth rate when the air was pushed toward the flame.

Effect of residual chemicals on wormlike micelles assembled from a C22-tailed cationic surfactant.

HYPOTHESIS: Ultra-long-chain surfactants, particularly C22-tailed ones, have attracted considerable attention because of their ease of self-assembly into wormlike micelles (WLMs). Commercial C22-tailed surfactants often contain non-negligible amounts of chemical residues introduced during their production. Since the noncovalent driving force of wormlike self-assembly can be greatly affected by the composition, we hypothesized that the residual chemicals could play a significant role in tuning the micelle microstructure and macroscopic properties of the surfactants. EXPERIMENTS: To confirm this hypothesis, a highly pure (>99%) C22-tailed cationic surfactant, N-erucylamidopropyl-N,N,N-trimethylammonium iodide (EDAI) was synthesized, and various amounts of corresponding reactants (iodomethane or N-erucamidopropyl-N,N-dimethylamine) or solvents (acetone) commonly used in surfactant synthesis were introduced as residues. The impact of each individual residue on the macroscopic appearances, rheological properties, and micelle morphology of the surfactant solution were investigated. FINDINGS: Increasing the residue fraction in the EDAI solution resulted in an initial increase, followed by a dramatic drop in solution viscosity. This behavior was described in terms of micellar structural transformations based on analysis of cryo-TEM observations and surface tension measurements. These findings are of crucial importance in understanding the sophisticated behaviors of WLMs and will benefit the industrial preparation of ultra-long-chain surfactants for commercial use.

CO2-Triggered microreactions in liquid marbles.

On-demand initiation of dual- and multi-component microreactions inside liquid marbles (LMs) was developed by coalescing contacting patchy LMs containing separate reagents through CO2-induced wetting transition of the interface between the LMs.

CO2 switchable hollow nanospheres.

HYPOTHESIS: Hollow nanospheres, characterized by a cavity inside a solid shell, have potential applications due to their unique structure, but the unchangeable morphology and permeability of the shell restrain their further practical utilization. While several smart hollow nanospheres that can respond to pH, ion strength, and temperature have been developed, they are inclined to suffer from problems associated with high energy consumption or the difficult removal of residual stimulants. Thus, it is desirable to develop a novel and free-of-residual trigger stimulating mode. EXPERIMENTS: In this work, CO2 is used to fabricate smart hollow nanospheres composed of crosslinked poly(diethylamino-ethyl methacrylate) (PDEAEMA) network from polystyrene (PS)/PDEAEMA core-shell nanospheres by a template-removal technique. The morphology evolution of the resultant nanospheres during the fabrication process was characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermogravimetry analysis (TGA) and dynamic light scattering (DLS) and was visualized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). FINDINGS: Hollow nanospheres can be generated by experiencing a morphology change from a core nanosphere, core-shell, yolk-shell to a final hollow structure. The increase in shell-stiffness can restrain the collapse of hollow spheres. It is demonstrated that CO2 is easy to introduce and remove (via N2 input) without stimulation residues in this system. In addition, mild CO2/N2 purging can only reversibly change the swelling/collapse of hollow particles; violent CO2/N2 bubbling can reversibly regulate both the size and aggregation/re-dispersion state of the hollow nanospheres, which can be intuitively observed by atomic force microscopy (AFM).