The surge of patients in the pandemic of COVID‐19 caused by the novel coronavirus SARS‐CoV‐2 may overwhelm the medical systems of many countries. Mask‐wearing and handwashing can slow the spread of ...the virus, but currently, masks are in shortage in many countries, and timely handwashing is often impossible. In this study, the efficacy of three types of masks and instant hand wiping was evaluated using the avian influenza virus to mock the coronavirus. Virus quantification was performed using real‐time reverse transcription‐polymerase chain reaction. Previous studies on mask‐wearing were reviewed. The results showed that instant hand wiping using a wet towel soaked in water containing 1.00% soap powder, 0.05% active chlorine, or 0.25% active chlorine from sodium hypochlorite removed 98.36%, 96.62%, and 99.98% of the virus from hands, respectively. N95 masks, medical masks, and homemade masks made of four‐layer kitchen paper and one‐layer cloth could block 99.98%, 97.14%, and 95.15% of the virus in aerosols. Medical mask‐wearing which was supported by many studies was opposed by other studies possibly due to erroneous judgment. With these data, we propose the approach of mask‐wearing plus instant hand hygiene (MIH) to slow the exponential spread of the virus. This MIH approach has been supported by the experiences of seven countries in fighting against COVID‐19. Collectively, a simple approach to slow the exponential spread of SARS‐CoV‐2 was proposed with the support of experiments, literature review, and control experiences.
0D/2D heterojunctions, especially quantum dots (QDs)/nanosheets (NSs) have attracted significant attention for use of photoexcited electrons/holes due to their high charge mobility. Herein, ...unprecedent heterojunctions of vanadate (AgVO3, BiVO4, InVO4 and CuV2O6) QDs/graphitic carbon nitride (g‐C3N4) NSs exhibiting multiple unique advances beyond traditional 0D/2D composites have been developed. The photoactive contribution, up‐conversion absorption, and nitrogen coordinating sites of g‐C3N4 NSs, highly dispersed vanadate nanocrystals, as well as the strong coupling and band alignment between them lead to superior visible‐light‐driven photoelectrochemical (PEC) and photocatalytic performance, competing with the best reported photocatalysts. This work is expected to provide a new concept to construct multifunctional 0D/2D nanocomposites for a large variety of opto‐electronic applications, not limited in photocatalysis.
Vanadate quantum dots including AgVO3, BiVO4, InVO4, and CuV2O6 were strongly coupled with graphitic carbon nitride nanosheets using an in situ growth strategy. These quantum dots displayed a much better visible‐light‐driven photoelectrochemical activity and photocatalytic degradation efficiency than single vanadate quantum dots, carbon nitride nanosheets or previously reported highly active photocatalysts.
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•The GO/MOFs nanocomposites can be used as applicable nanocontainers.•Inhibitor-encapsulated GO/MOFs nanocontainers exhibit both passive and active protecting properties.•The method ...of preparing GO/MOFs nanocontainers is facile and versatile by just one-pot reaction.
In this work, metal organic frameworks (MOFs) are in situ growing on the graphene oxide (GO) sheets to fabricate GO/MOFs nanocontainers for both active and passive corrosion protection. ZIF-8 and UiO-66 are chosen as two classic examples to synthesize GO/MOFs nanocontainers encapsulating benzotriazole (BTA) embedded in polyvinyl butyral (PVB) resin. The composite coatings are successfully utilized in protecting pure copper and archaized bronze, exhibiting both active and passive protecting properties. The passive protection capability is ensured by good barrier performance of GO, and the active prevention property is provided by the pH-stimulated release of embedded inhibitors from the composite nanocontainers.
Arsenic (As) contamination in a paddy environment can cause phytotoxicity and elevated As accumulation in rice (Oryza sativa). The mechanism of As detoxification in rice is still poorly understood.
...We isolated an arsenate (As(V))-sensitive mutant of rice. Genomic resequencing and complementation identified OsCLT1, encoding a CRT-like transporter, as the causal gene for the mutant phenotype.
OsCLT1 is localized to the envelope membrane of plastids. The glutathione and γ-glutamylcysteine contents in roots of Osclt1 and RNA interference lines were decreased markedly compared with the wild-type (WT). The concentrations of phytochelatin PC2 in Osclt1 roots were only 32% and 12% of that in WT after As(V) and As(III) treatments, respectively. OsCLT1 mutation resulted in lower As accumulation in roots but higher As accumulation in shoots when exposed to As(V). Under As(III) treatment, Osclt1 accumulated a lower As concentration in roots but similar As concentration in shoots to WT. Further analysis showed that the reduction of As(V) to As(III) was decreased in Osclt1. Osclt1 was also hypersensitive to cadmium (Cd).
These results indicate that OsCLT1 plays an important role in glutathione homeostasis, probably by mediating the export of γ-glutamylcysteine and glutathione from plastids to the cytoplasm, which in turn affects As and Cd detoxification in rice.
Zn-Al layered double hydroxide (LDH) pretreatment layer was prepared by a novel two-step electrochemical method on galvanized steel surface from a precursor solution containing Al3+-only. In the ...first step, anodic currents are applied to Zn deposit to produce Zn2+ in solution near the substrate surface. Cathodic currents are then applied to ensure the cathodic deposition of LDH film. The obtained LDH coatings not only provide excellent adhesion to the metal surface, but also enhance the adhesion between metal substrate and the top epoxy coatings. The “LDH/epoxy” painting system can protect galvanized steel from rusting for at least 150 days.
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•A novel two-step electrochemical method is proposed to prepare layered double hydroxide (LDH) pretreatment layer.•The electrochemical method takes only 5 minutes and can be performed at room temperature.•The obtained LDH pretreatment layer exhibits unique vertically-grown morphology.•LDH pretreatment layer greatly enhanced the adhesion between metal substrate and the top epoxy coatings.•The “LDH/epoxy” painting system can protect galvanized steel from rusting for at least 150 days.
The coronavirus disease 2019 pandemic caused by the novel coronavirus SARS‐CoV‐2 (severe acute respiratory syndrome coronavirus 2) has claimed many lives worldwide. Wearing medical masks (MMs) or N95 ...masks (N95Ms namely N95 respirators) can slow the virus spread and reduce the infection risk. Reuse of these masks can minimize waste, protect the environment, and help solve the current imminent shortage of masks. Disinfection of used masks is needed for their reuse with safety, but improper decontamination can damage the blocking structure of masks. In this study, we demonstrated using the avian coronavirus of infectious bronchitis virus to mimic SARS‐CoV‐2 that MMs and N95Ms retained their blocking efficacy even after being steamed on boiling water for 2 hours. We also demonstrated that three brands of MMs blocked over 99% viruses in aerosols. The avian coronavirus was completely inactivated after being steamed for 5 minutes. Altogether, this study suggested that MMs are adequate for use on most social occasions and both MMs and N95Ms can be reused for a few days with steam decontamination between use.
Highlights
Reuse of medical masks and N95 respirators is highly needed.
The masks have excellent efficacy in blocking coronaviruses in aerosols.
The masks should be decontaminated for reuse.
The masks maintain their blocking efficacy after being steamed on boiling water.
The steam measure can inactivate coronaviruses completely.
Superhydrophobic silica films were deposited onto mild steel substrate for the purpose of corrosion protection. The superhydrophobicity was obtained by one-step electrodeposition of inorganic/organic ...hybrid sol–gel films from tetraethoxysilane and dodecyltriethoxysilane mixed sol–gel precursors, as a result of simultaneous generation of high roughness and low-energy surface. The corrosion performance was investigated by monitoring the change of water contact angle, by the electrochemical impedance spectroscopy measurements and by iron dissolution test over the whole immersion time. The results show that the superhydrophobic film provides an effective barrier coating for the mild steel interface.
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•A simple one-step preparation of inhibitor-loaded mesoporous SiO2 nanocontainers was designed.•The new one-step method was efficient, energy-saving and organic solvents-free compared ...with traditional multi-step preparations.•The resultant nanocontainers had high uptake of inhibitor (∼16 wt.%) and possessed pH-responsive inhibitor release property.•The coating incorporated with the nanocontainers significantly improved the corrosion resistance of copper substrate.
We present a simple one-step method of preparing inhibitor-loaded mesoporous silica nanocontainers without extra steps such as template removal or inhibitors loading. The synthetic method is based on the high solubility of organic inhibitors in hydrophobic cores of template micelles. The resultant inhibitor (benzotriazole) and cetyltrimethyl ammonium bromide (CTAB) co-loaded silica nanocontainers had high uptake of inhibitor (∼16 wt.%) and possessed H+ ion-responsive inhibitor release property. When examined by scanning vibrating electrode technique, the coating doped with these nanocontainers exhibits effective corrosion protection property. These results suggest that the one-step synthetic method was efficient, energy-saving and organic solvents-free among others.
One of the biggest obstacles for superhydrophobic films in applications is their poor mechanical resistance. In this research, robust superhydrophobic SiO2 films were constructed on mild steel (MS) ...for corrosion protection by the combination of rough electrodeposited SiO2 (E-SiO2) films and durable polydimethylsiloxane (PDMS) polymer with low surface energy. Results show that the PDMS content has a great effect on the microtopography, wettability, roughness, and wear-resistance of the final films. EIS measurements indicate that as-prepared robust superhydrophobic E-SiO2/PDMS films exhibit good corrosion inhibition efficiency of up to 99.99 % for MS substrates in 3.5 wt.% NaCl solution.
Oxygen activation plays a crucial role in many important chemical reactions such as oxidation of organic compounds and oxygen reduction. For developing highly active materials for oxygen activation, ...herein, we report an atomically dispersed Pt on WO3 nanoplates stabilized by in situ formed amorphous H2WO4 out‐layer and the mechanism for activating molecular oxygen. Experimental and theoretical studies demonstrate that the isolated Pt atoms coordinated with oxygen atoms from WO6 and water of H2WO4, consequently leading to optimized surface electronic configuration and strong metal–support interaction (SMSI). In exemplified reactions of butanone oxidation sensing and oxygen reduction, the atomic Pt/WO3 hybrid exhibits superior activity than those of Pt nanoclusters/WO3 and bare WO3 as well as enhanced long‐term durability. This work will provide insight into the origin of activity and stability for atomically dispersed materials, thus promoting the development of highly efficient and durable single atom‐based catalysts.
Single atom‐based catalysts: Atomically dispersed Pt species have been stabilized by an in situ formed amorphous H2WO4 layer. The Pt atoms were coordinated by oxygen atoms from the WO6 octahedra of H2WO4 and water molecules. A strong metal–support interaction was observed between the Pt atoms and the oxide atoms of H2WO4, which resulted in a superior activity and stability of the Pt atoms for the oxygen activation.
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