Water transport rate in network membranes is inversely correlated to thickness, thus superior permeance is achievable with ultrathin membranes prepared by complicated methods circumventing nanofilm ...weakness and defects. Conferring ultrahigh permeance to easily prepared thicker membranes remains challenging. Here, a tetrakis(hydroxymethyl) phosphonium chloride (THPC) monomer is discovered that enables straightforward modification of polyamide composite membranes. Water permeance of the modified membrane is ≈6 times improved, give rising to permeability (permeance × thickness) one magnitude higher than state‐of‐the‐art polymer nanofiltration membranes. Meanwhile, the membrane exhibits good rejection (RNa2SO4 = 98%) and antibacterial properties under crossflow conditions. THPC modification not only improves membrane hydrophilicity, but also creates additional angstrom‐scale channels in polyamide membranes for unimpeded transport of water. This unique mechanism provides a paradigm shift in facile preparation of ultrapermeable membranes with unreduced thickness for clean water and desalination.
Facile modification of polyamide composite membranes by an inexpensive phosphonium monomer featuring tetrahedral geometry is found to create additional water transport channels, improving the water purification performance without reducing film thickness. Compared with cutting‐edge ultrathin membranes, the modified membrane highlights good rejection, antibacterial properties, superior water permeability, and facile preparation.
The robustness of carbon nanomaterials and their potential for ultrahigh permeability has drawn substantial interest for separation processes. However, graphene oxide membranes (GOms) have ...demonstrated limited viability due to instabilities in their microstructure that lead to failure under cross-flow conditions and applied hydraulic pressure. Here we present a highly stable and ultrapermeable zeolitic imidazolate framework-8 (ZIF-8)-nanocrystal-hybridized GOm that is prepared by ice templating and subsequent in situ crystallization of ZIF-8 at the nanosheet edges. The selective growth of ZIF-8 in the microporous defects enlarges the interlayer spacings while also imparting mechanical integrity to the laminate framework, thus producing a stable microstructure capable of maintaining a water permeability of 60 l m
h
bar
(30-fold higher than GOm) for 180 h. Furthermore, the mitigation of microporous defects via ZIF-8 growth increased the permselectivity of methyl blue molecules sixfold. Low-field nuclear magnetic resonance was employed to characterize the porous structure of our membranes and confirm the tailored growth of ZIF-8. Our technique for tuning the membrane microstructure opens opportunities for developing next-generation nanofiltration membranes.
Conductive polymers are recognized as ideal candidates for the development of noninvasive and wearable sensors for real‐time monitoring of potassium ions (K+) in sweat to ensure the health of life. ...However, the low ion‐to‐electron transduction efficiency and limited active surface area hamper the development of high‐performance sensors for low‐concentration K+ detection in the sweat. Herein, a wearable K+ sensor is developed by tailoring the nanostructure of polypyrrole (PPy), serving as an ion‐to‐electron transduction layer, for accurately and stably tracing the K+ fluctuation in human sweat. The PPy nanostructures can be tailored from nanospheres to nanofibers by controlling the supramolecular assembly process during PPy polymerization. Resultantly, the ion‐to‐electron transduction efficiency (17‐fold increase in conductivity) and active surface area (1.3‐fold enhancement) are significantly enhanced, accompanied by minimized water layer formation. The optimal PPy nanofibers‐based K+ sensor achieved a high sensitivity of 62 mV decade−1, good selectivity, and solid stability. After being integrated with a temperature sensor, the manufactured wearable sensor realized accurate monitoring of K+ fluctuation in the human sweat.
The polypyrrole (PPy) nanostructures are tailored from nanospheres to nanofibers via controlling the supramolecular assembly process, which is utilized as the ion‐to‐electron conductive layer. Resultantly, the ion‐to‐electron transduction efficiency and active surface area are significantly enhanced, accompanied by minimized water layer formation. The optimal PPy nanofiber‐based potassium ion (K+) sensor achieved a high sensitivity of 62 mV decade−1, good selectivity, and solid stability.
With the increasing demands for novel flexible organic electronic devices, conductive polymers are now becoming the rising star for reaching such targets, which has witnessed significant ...breakthroughs in the fields of thermoelectric devices, solar cells, sensors, and hydrogels during the past decade due to their outstanding conductivity, solution‐processing ability, as well as tailorability. However, the commercialization of those devices still lags markedly behind the corresponding research advances, arising from the not high enough performance and limited manufacturing techniques. The conductivity and micro/nano‐structure of conductive polymer films are two critical factors for achieving high‐performance microdevices. In this review, the state‐of‐the‐art technologies for developing organic devices by using conductive polymers are comprehensively summarized, which will begin with a description of the commonly used synthesis methods and mechanisms for conductive polymers. Next, the current techniques for the fabrication of conductive polymer films will be proffered and discussed. Subsequently, approaches for tailoring the nanostructures and microstructures of conductive polymer films are summarized and discussed. Then, the applications of micro/nano‐fabricated conductive films‐based devices in various fields are given and the role of the micro/nano‐structures on the device performances is highlighted. Finally, the perspectives on future directions in this exciting field are presented.
Micro/nano‐structured conductive polymer films are critical for achieving high‐performance organic electronic devices. This review covers various micro/nano‐fabrication techniques and applications of micro/nano‐fabricated conductive films‐based devices in various fields such as sensors, energy devices, photonic devices, and actuators. The micro/nano‐structures play an important role in improving their performances.
Organic solvent nanofiltration (OSN) is emerging as an efficient and emerging approach for separation and purification of solute from organic solvents, which however were severely underdeveloped ...because of the low permeance of membranes. Herein, a novel mixed matrix membrane (MMM) was developed by incorporation of modified mesoporous silica nanoparticle (MSN) into commercially-available polydimethylsiloxane (PDMS) matrix for removal of trace impurities, such as Evans blue or vitamin B12, from different organic solvents. Notably, because of the designed nanoscale spaces originated from MSN, the permeance of the optimized MMM reached up to 31.2 L m−2.h−1.MPa−1, around 17-fold enhancement compared with that of pristine PDMS membrane. Low-field nuclear magnetic resonance was employed to trace the solvent state in the MMM. The MMM exhibited high MeOH absorption capability but low-swelling attribute, certificating the high permeance and long-term stability of the MMM. The MMM was stably tested in MeOH solution for more than 80 h, indicating the great promise for future practical OSN applications.
Schematic illustration of transportation of methanol molecules in mMSN/PDMS OSN membrane. Display omitted
•MMM was developed by incorporation of modified MSN into commercially-available PDMS for OSN separation.•The permeance of PDMS was 17-fold enhanced for OSN separation of Evans blue or VB12 in solvent.•LF-NMR was utilized to investigate the deformation mechanisms in the membranes.
Pervaporation has great potential in the separation of many significant mixtures. However, excessive penetration of separation layer into the substrate pores enhances the transport resistance of ...solvent molecules, which impedes the development of pervaporation membrane. In this study, a facile floating‐on‐water (FOW) method was used to prepare poly(dimethylsiloxane) (PDMS)/polytetrafluoroethylene (PTFE) composite membranes. The formation of separation layer and preparation of composite membrane were step‐by‐step completed through this liquid–liquid interface induced method. The PDMS layer thickness could be precisely regulated from 0.5 to 8 μm. Moreover, the pore penetration could be controlled by optimizing pre‐crosslinking density, crosslinking time on water and polymer solution volume. The obtained PDMS/PTFE composite membrane exhibited a high flux of 2016 g·m−2·h−1 with the separation factor of 12 when separating ethanol from a 5 wt% ethanol/water mixture. The performance of the membrane could be stable for over 200 h, exhibiting great potential in ethanol perm‐selective pervaporation.
MiR‐27 prevents atherosclerosis by inhibiting inflammatory responses induced by lipoprotein lipase. Overexpression of miR‐27b attenuates angiotensin‐induced atrial fibrosis. Nevertheless, studies ...have rarely investigated on the effect of miR‐27 in cardiomyocyte injury. H9c2 cells were transfected with miR‐27 mimic/inhibitor. Then the cell proliferation was tested by MTT assay and the cell apoptosis was detected by flow cytometry. The luciferase activity assay was utilized to analyze the relationship between miR‐27 and TGFBR1. Quantificational real‐time polymerase chain reaction and western blot were utilized to detect the cardiomyocyte differentiation marker and nuclear factor kappa B (NF‐κB) pathway. Our outcomes demonstrated that miR‐27 expression was downregulated cardiomyocyte injury subjected to hypoxia/reoxygenation (H/R). Additionally, overexpression of miR‐27 could significantly alleviate cardiomyocyte injury by regulating cell activity and apoptosis. The luciferase activity assay confirmed that transforming growth factor ß receptor 1 (TGFBR1) is a direct hallmark of miR‐27. Besides, overexpression of miR‐27 promoted the expression of TGFBR1 in H/R model. After transfection with miR‐27 mimic/inhibitor, the expression of NF‐κB pathway‐related proteins was decreased/increased. Taken together, our data manifested that miR‐27 repressed cardiomyocyte injury induced by H/R via mediating TGFBR1 and inhibiting NF‐κB signaling pathway. Furthermore, miR‐27/ TGFBR1 might be utilized as hopeful biomarkers for myocardial ischemia diagnosis and treatment.
Walker (Lepidoptera: Pyralididae) is a serious pest in the sericulture industry, which has caused damage and losses in recent years. With the widespread use of insecticides, the insecticide ...resistance of
has becomes increasingly apparent. In order to find other effective methods to control
, this study performed a transcriptome analysis of the midgut, integument, and whole larvae. Transcriptome data were annotated with KEGG and GO, and they have been shown to be of high quality by RT-qPCR. The different significant categories of differentially expressed genes between the midgut and the integument suggested that the transcriptome data could be used for next analysis. With the exception of Dda9 (GpCDA5), 19 genes were involved in chitin metabolism, most of which had close protein-protein interactions. Among them, the expression levels of 11 genes, including
,
,
,
,
,
,
,
,
,
, and
were higher in the integument than in the midgut, while the expression levels of the last eight genes, including
,
,
,
,
,
,
, and
, were higher in the midgut than in the integument. Moreover, 282 detoxification-related genes were identified and can be divided into 10 categories, including cytochrome P450, glutathione S-transferase, carboxylesterase, nicotinic acetylcholine receptor, aquaporin, chloride channel, methoprene-tolerant, serine protease inhibitor, sodium channel, and calcium channel. In order to further study the function of chitin metabolism-related genes, dsRNA injection knocked down the expression of
and
, resulting in the significant downregulation of its downstream genes. These results provide an overview of chitin metabolism and detoxification of
and lay the foundation for the effective control of this pest in the sericulture industry.
Functional membranes generally wear out when applying in harsh conditions such as a strong acidic environment. In this work, high acid‐resistance, long‐lasting, and low‐cost functional membranes are ...prepared from engineered hydrogen‐bonding and pH‐responsive supramolecular nanoparticle materials. As a proof of concept, the prepared membranes for dehydration of alcohols are utilized. The synthesized membranes have achieved a separation factor of 3000 when changing the feed solution pH from 7 to 1. No previous reports have demonstrated such unprecedentedly high‐record separation performance (pervaporation separation index is around 1.1 × 107 g m−2 h−1). More importantly, the engineered smart membrane possesses fast self‐repairing ability (48 h) that is inherited from the dynamic hydrogen bonds between the hydroxyl groups of polyacrylic acid and carbonyl groups of polyvinylpyrrolidone. To this end, the designed supramolecular materials offer the membrane community a new material type for preparing high acid resistance and long‐lasting membranes for harsh environmental cleaning applications.
Size‐tunable hydrogen‐bond supramolecular nanoparticles are synthesized for separation membrane fabrication, which can work stably at pH = 1 condition and exhibit self‐repairing ability.
•An facile preparation method of magnetic superhydrophobic Fe3O4/PU sponge for oil-water separation is proposed.•The Fe3O4/PU sponge can be used to absorb oil from water followed by magnetic recovery ...and to realize the oil-water separation as a filter.•The absorptive abilities of Fe3O4/PU sponges for pump oil, peanut oil, and silicone oil are good.
Fe3O4 nanoparticles were modified by tetraethoxysilane and different amounts of trimethoxy (1H,1H,2H,2H-heptadecafluorodecyl) silane in sequence to obtain the magnetic nanoparticles with low surface energy, which could be used to construct the superhydrophobic surfaces for PU sponge, cotton fabric, and filter paper by a simple drop-coating method. Particularly, all the resultant Fe3O4/PU sponges containing different fluoroalkylsilane-modified Fe3O4 nanoparticles possessed both high water repellency with contact angle in the range of 150.2–154.7° and good oil affinity, which could not only effectively remove oil from water followed by convenient magnetic recovery but also easily realize the oil-water separation as a filter only driven by gravity. The Fe3O4/PU sponges showed high absorption capability of peanut oil, pump oil, and silicone oil with the maximum absorptive capacities of 40.3, 39.3, and 46.3g/g, respectively. Such novel sponges might be a potential candidate for oil-water separation as well as oil absorption and transportation accompanied by the advantages of simple process, remote control by magnetic field, and low energy consumption.
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