Publications by authors named "Longcheng Gao"

Achieving multi-spectrum compatible stealth in radar-terahertz-infrared bands with robust performance has great prospects for both military and civilian applications. However, the progress of materials encounters substantial challenges due to the significant variability in frequency coupling properties across different electromagnetic wave bands. Here, this work presents the design of a multi-scale structure and fabricates a lightweight aerogel (silver nanowire@carbon, AgNW@C) consisting of a regular coaxial nano-cable, with silver nanowire as the core and amorphous-graphitized hybrid carbon as the outer-layer.

View Article and Find Full Text PDF

Osmotic energy, a renewable clean energy, can be directly converted into electricity through ion-selective membranes. Inspired by the magnesium porphyrin (Mg) in plant chlorophyll, which absorbs vis-light and promotes photoelectric conversion, we demonstrate a Mg array membrane, realizing vis-light-enhanced ion transport regulation ability and osmotic energy conversion. The Mg arrays are self-assembled by a Mg-cored block copolymer under the coordination effect of block copolymer self-assembly and Mg π-π stacking, providing chloride-selective transport channels.

View Article and Find Full Text PDF

Highly-dense small-feature-size nanopatterns and nanoporous membranes are important in advanced microelectronics, nanofiltration, and biomimic device manufacturing. Here, we report the synthesis and self-assembly of a series of high-interaction-parameter (high-χ) silicon-containing hierarchical block copolymers (BCPs) with cross-linkable subordering chalcone motifs, which possess both an intrinsic native etching contrast for nanofabrication and cross-linkability under ultraviolet light for generating free-standing membranes. BCPs with a volume fraction of chalcone block of 55-74% form ordered primary nanostructures with period 15-22 nm including lamellae, double gyroid, hexagonally packed cylinders, and body-centered cubic spheres of the minority Si-containing block.

View Article and Find Full Text PDF

The osmotic energy, an abundant renewable energy source, can be directly converted to electricity by nanofluidic devices with ion-selective membranes. 2D nanochannels constructed by nanosheets possess abundant lateral interfacial ion-exchange sites and exhibit great superiority in nanofluidic devices. However, the most accessible orientation of the 2D nanochannels is parallel to the membrane surface, undoubtedly resulting in the conductivity loss.

View Article and Find Full Text PDF

Halorhodopsin, a light-driven chloride pump, utilizes photonic energy to drive chloride ions across biological membranes, regulating the ion balance and conveying biological information. In the light-driven chloride pump process, the chloride-binding chromophore (protonated Schiff base) is crucial, able to form the active center by absorbing light and triggering the transport cycle. Inspired by halorhodopsin, we demonstrate an artificial light-driven chloride pump using a helical porphyrin channel array with excellent photoactivity and specific chloride selectivity.

View Article and Find Full Text PDF

Minority groups are non-repeating units with very low content that inevitably exist in polymers. Typically, these minority groups are easily surrounded by the majority of repeating units and randomly dispersed, maximizing the entropy of minority groups. In the concept, anti-entropy aggregation (AEA) of minority groups is described, and different pathways are outlined.

View Article and Find Full Text PDF

Mechanosensitive ion channels play crucial roles in physiological activities, where small mechanical stimuli induce the membrane tension, trigger the ion channels' deformation, and are further transformed into significant electrochemical signals. Artificial ion channels with stiff moduli have been developed to mimic mechanosensory behaviors, exhibiting an electrochemical response by the high-pressure-induced flow. However, fabricating flexible mechanosensitive channels capable of regulating specific ion transporting upon dramatic deformation has remained a challenge.

View Article and Find Full Text PDF

The gel modulus, a key parameter for gel materials, is traditionally determined by cumbersome rheometer. Recently, probe technologies occur to meet the requirements of in situ determination. Till now, in situ and quantitatively testing of gel materials with unabridged structure informations still remains a challenge.

View Article and Find Full Text PDF

Ion-exchange membranes (IEMs) convert osmotic energy into electricity when embedded in a reverse electrodialysis cell. IEMs with both high permselectivity and ionic conductivity are highly needed to increase the energy conversion efficiency. The ionic conductivity can be improved by increasing the content of immobile charge carriers, but it is always accompanied by undesirable permselectivity decrease due to excess swelling.

View Article and Find Full Text PDF

Ion selectivity is an essential property of ion-selective membranes (ISMs). To date, all of the artificial ISMs have been reported to exhibit sole ion selectivity (SIS), either cation or anion selectivity. Here, we first demonstrate unconventional dual ion selectivity (DIS) in a bipolar channel membrane determined by the forward side toward ion flux.

View Article and Find Full Text PDF
Article Synopsis
  • The text discusses a new type of membrane for converting osmotic energy into electricity that outperforms previous designs in terms of power density and stability.
  • The membrane features a unique mushroom-shaped structure with a highly dense array of nanochannels, allowing it to generate an impressive power density of 22.4 W·m at a significant salinity gradient.
  • The design combines a negatively charged 1D nanochannel array with a selective layer made of hyperbranched polyethyleneimine, showcasing a novel method for efficient large-scale energy conversion.
View Article and Find Full Text PDF

Vitrimers are one kind of covalently crosslinked polymers that can be reprocessed. Topology freezing transition temperature (T) is vitrimer's upper limit temperature for service and lower temperature for recycle. However, there has been no proper method to detect the intrinsic T till now.

View Article and Find Full Text PDF

Electric eels can generate high potential bioelectricity because of the numerous electrocytes, where the cell membranes contain ion-selective channels. Net electric current is formed by the directional permeation of ions across the channels. Many nanofluidic devices have been designed for energy conversion.

View Article and Find Full Text PDF

Gas messenger molecule (NO) plays important roles in K nanochannels of guard cells by binding directly to the heme-containing enzymes. Inspired by this natural phenomenon, we developed artificial K nanochannels modified with ferroporphyrin, where NO triggered the nanochannels to turn "ON" states from the ferroporphyrin blocked "OFF" states. The mechanism relies on the fact that NO has higher affinity with ferroporphyrin compared to carboxyl groups on the nanochannel surface.

View Article and Find Full Text PDF

The osmotic energy existing in fluids is recognized as a promising "blue" energy source that can help solve the global issues of energy shortage and environmental pollution. Recently, nanofluidic channels have shown great potential for capturing this worldwide energy because of their novel transport properties contributed by nanoconfinement. However, with respect to membrane-scale porous systems, high resistance and undesirable ion selectivity remain bottlenecks, impeding their applications.

View Article and Find Full Text PDF

A CO-regulated ion nanochannel is demonstrated, which is inspired by the living activity of CO-induced smooth muscle vasodilation. The mechanism relies on the fact that CO has a higher affinity with ferroporphyrin compared to carboxyl groups on the surface of the nanochannels. The cooperation effect of the released carboxyl groups and the conical asymmetric shape leads the ion transportation to be diode-like.

View Article and Find Full Text PDF

pH-gated ion channels in cell membranes play important roles in the cell's physiological activities. Many artificial nanochannels have been fabricated to mimic the natural phenomenon of pH-gated ion transport. However, these nanochannels show pH sensitivity only within certain pH ranges.

View Article and Find Full Text PDF

Sphingomonas paucimobilis strain LCT-SP1 is a glucose-nonfermenting Gram-negative, chemoheterotrophic, strictly aerobic bacterium. The major feature of strain LCT-SP1, isolated from the Chinese spacecraft Shenzhou X, together with the genome draft and annotation are described in this paper. The total size of strain LCT-SP1 is 4,302,226 bp with 3,864 protein-coding and 50 RNA genes.

View Article and Find Full Text PDF

The role of gut bacteria of mealworms (the larvae of Tenebrio molitor Linnaeus) in polystyrene (PS) degradation was investigated. Gentamicin was the most effective inhibitor of gut bacteria among six antibiotics tested. Gut bacterial activities were essentially suppressed by feeding gentamicin food (30 mg/g) for 10 days.

View Article and Find Full Text PDF

Polystyrene (PS) is generally considered to be durable and resistant to biodegradation. Mealworms (the larvae of Tenebrio molitor Linnaeus) from different sources chew and eat Styrofoam, a common PS product. The Styrofoam was efficiently degraded in the larval gut within a retention time of less than 24 h.

View Article and Find Full Text PDF

Controlled directional spreading of a droplet on a smart high-adhesion surface was made possible by simply controlling anodic oxidation. The wettability gradient of the surface was controlled from 0.14 to 3.

View Article and Find Full Text PDF

We designed a kind of smart bioinspired fiber using the N-isopropylacrylamide (NIPAAm) polymer, with roughness and curvature features similar to those of wetted spider silk. The motion of tiny water droplets can be manipulated reversibly in directions by the effective cooperation of multi-gradients such as roughness, curvature and temperature-responsive wettability.

View Article and Find Full Text PDF

A temperature controlled dual water/oil on-off switch is achieved by using a PMMA-b-PNIPAAm block-copolymer coated mesh, determined by the conformational change of the PNIPAAm chain around the lower critical solution temperature (LCST) and also the cooperation between PNIPAAm and PMMA. Water can permeate through the BCP-coated mesh, and oil cannot below the LCST, whereas oil can and water cannot above the LCST.

View Article and Find Full Text PDF