Besides the pandemic caused by the coronavirus outbreak, many other pathogenic microbes also pose a devastating threat to human health, for instance, pathogenic bacteria. Due to the lack of ...broad‐spectrum antibiotics, it is urgent to develop nonantibiotic strategies to fight bacteria. Herein, inspired by the localized “capture and killing” action of bacteriophages, a virus‐like peroxidase‐mimic (V‐POD‐M) is synthesized for efficient bacterial capture (mesoporous spiky structures) and synergistic catalytic sterilization (metal–organic‐framework‐derived catalytic core). Experimental and theoretical calculations show that the active compound, MoO3, can serve as a peroxo‐complex‐intermediate to reduce the free energy for catalyzing H2O2, which mainly benefits the generation of •OH radicals. The unique virus‐like spikes endow the V‐POD‐M with fast bacterial capture and killing abilities (nearly 100% at 16 µg mL–1). Furthermore, the in vivo experiments show that V‐POD‐M possesses similar disinfection treatment and wound skin recovery efficiencies to vancomycin. It is suggested that this inexpensive, durable, and highly reactive oxygen species (ROS) catalytic active V‐POD‐M provides a promising broad‐spectrum therapy for nonantibiotic disinfection.
A bioinspired, spiky, and highly catalytic‐active virus‐like peroxidase‐mimic (V‐POD‐M) is synthesized for the localized “capture and killing” eradication of pathogenic bacteria. Experimental and theoretical calculations demonstrate that the V‐POD‐M exhibits strong bacterial interactions and efficient capture, synergistic catalytic sterilization, and similar in vivo disinfection efficiency to that of vancomycin, which provides a promising broad‐spectrum therapy for nonantibiotic disinfection.
Metal oxides (MOs) have been widely investigated as promising high-capacity anode material for lithium ion batteries, but they usually exhibit poor cycling stability and rate performance due to the ...huge volume change induced by the alloying reaction with lithium. In this article, we present a double protection strategy by fabricating a two-dimensional (2D) core–shell nanostructure to improve the electrochemical performance of metal oxides in lithium storage. The 2D core–shell architecture is constructed by confining the well-defined graphene based metal oxides nanosheets (G@MO) within carbon layers. The resulting 2D carbon-coated graphene/metal oxides nanosheets (G@MO@C) inherit the advantages of graphene, which possesses high electrical conductivity, large aspect ratio, and thin feature. Furthermore, the carbon shells can tackle the deformation of MO nanoparticles while keeping the overall electrode highly conductive and active in lithium storage. As the result, the produced G@MO@C hybrids exhibit outstanding reversible capacity and excellent rate performance for lithium storage (G@SnO2@C, 800 mAh g–1 at the rate of 200 mA g–1 after 100 cycles; G@Fe3O4@C, 920 mAh g–1 at the rate of 200 mA g–1 after 100 cycles).
This article presents a synthesis method to design a new type of bandpass frequency selective surfaces (FSSs) with multiple transmission zeros (TZs). To briefly show the concept of our synthesis ...method, a generalized topology of the bandpass FSS based on cascaded slotline sections paralleled with bandpass resonators is first presented to map with an alternative <inline-formula> <tex-math notation="LaTeX">n </tex-math></inline-formula>th-order bandpass filtering network with <inline-formula> <tex-math notation="LaTeX">J </tex-math></inline-formula>-inverters and typical LC parallel resonators. Then, two kinds of composite LC parallel resonators, named as LC - LC and <inline-formula> <tex-math notation="LaTeX">{L} </tex-math></inline-formula> - LC parallel resonators, are introduced and discussed to replace the typical LC parallel resonators, which can produce TZs at skirts of the passband and increase the out-of-band selectivity. The derivations of equivalent relationships between the composite and typical LC resonators are given. Furthermore, for the exploration of bandpass FSS with multiple out-of-band TZs, the realization of these two discussed composite LC parallel resonators is exhibited by inductive and capacitive strip lines loading on slotline structures. The design curves and guidelines are given and discussed correspondingly. To validate our design concept, two FSS examples, a second-order bandpass FSS with four out-of-band TZs and a third-order one with five out-of-band TZs, are synthesized and designed. In final, these two designed bandpass FSS prototypes are fabricated and then measured by the free-space measurement method. The measured results show that the desired stable bandpass filtering performance and independently multiple out-of-band TZs are successfully realized.
The production of household wastes such as used frying oil (UFO) and plastic waste (PW) are increasing each year, thus representing potential feedstocks for conversion into an energy source. ...Microwave co-pyrolysis was investigated for its potential to transform a mixture of UFO and polyolefinic-based plastic waste into fuel product with desirable properties. The co-pyrolysis approach demonstrated positive synergistic effects in providing fast heating rate (up to 50 °C/min) and a lower reaction time (≤25 min), and generated up to 81 wt.% yield of liquid oil and 18 wt.% yield of pyrolysis gases for use as potential fuels. The liquid oil showed promising green properties comprising low oxygen content, free of nitrogen and sulphur and higher energy content (42–46 MJ/kg). The oil product also demonstrated improved stability and desirable fuel properties nearly similar to transport-grade diesel, thus indicating the great potential of microwave co-pyrolysis as an approach for transforming household wastes into value-added liquid fuel.
•Microwave co-pyrolysis of waste materials showed positive synergistic effects.•Microwave co-pyrolysis increased heating rates (50 °C/min) and cracking reactions.•High yield of oil product (up to 81 wt.%) with high energy content (42–45 MJ/kg).•Oil product showed green properties such as free of sulphur and nitrogen, low in oxygen.•Co-pyrolysis is a promising approach to convert household wastes into value-added fuel.
In this paper, a new class of wideband phase shifters on multimode resonator is proposed and developed. Compared with its conventional counterparts, these new phase shifters have a few advantageous ...features such as simple structure, intrinsic wideband characteristic, large phase-shift value, and easy adjustment in phase shift. The phase properties of multimode resonator are at first studied to derive the quantitative relationship between the phase slope and their respective resonant frequencies. On the one hand, a prescribed wideband phase shift can be achieved by adjusting the impedance ratio R z of the multimode resonator and the electrical length of the reference line. On the other hand, the wide operating band can be intrinsically obtained over a frequency range covered by multiple resonant frequencies in the multimode resonator. In this context, the transmission-line models of the proposed phase shifters are deduced and synthesized to design these phase shifters with a prescribed phase shift value and return loss within the operating band. Moreover, the synthesized model can be directly mapped into all the physical dimensions, thus allowing for a quick design process. Finally, two 180° wideband phase shifters are designed, fabricated, and tested to verify the proposed design method and predicted frequency responses.
Planar, two-dimensional, two-colour, time-resolved laser-induced incandescence (2D-2C-TiRe-LII) is employed to investigate the formation of soot in a standard methane laminar diffusion flame for the ...first time. The work builds on previous developments in 2D LII by time-resolving the signal decay by shifting the gating time of ICCD cameras. The two-colour configuration allows application of the technique to extract the initial temperature of soot particles immediately after the laser pulse, instead of relying on estimates of the soot absorption coefficient, thus allowing higher accuracy in the determination of very small particle sizes produced in methane flames, using a minimum error approach. The technique is combined with a previous work on Continuous Wave Laser Cavity Extinction (CW-LCE) to allow absolute measurements of sub-ppm low soot volume fractions with very small particle sizes.
Fluid mechanics concerns the mechanisms of liquids, gases and plasmas and the forces on them. We aim to investigate a
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-dimensional generalized nonlinear evolution system in fluid mechanics ...and plasma physics in this paper. With the help of the Painlevé analysis, we find that the above system has Painlevé-integrable property. A set of the auto-Bäcklund transformations and some solutions are derived by the virtue of the truncated Painlevé method. We obtain certain bilinear forms via some seed solutions. According to the mentioned bilinear form, we derive the multiple-soliton solutions on some nonzero backgrounds. Based on the soliton solutions and conjugation transformations, the higher-order breather solutions on certain nonzero backgrounds have been obtained. Via some conjugation transformations, hybrid solutions formed from the breathers and solitons on certain nonzero backgrounds have been derived. We also graphically show the interactions between those solitons and breathers.
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•Practicality of photocatalytic water splitting is assessed from various aspects.•Employments of unrealistic labscale investigation are pointed out.•Intrinsic limitations of ...photocatalytic water splitting are summarized.•Energy and economy analysis of photocatalytic water splitting are performed.•H2 energy generation from photocatalytic water splitting is not industrially viable.
Reaping hydrogen energy by utilising eternal sunlight offers a good fit to the theme of popularly-hype sustainable and carbon-free energy future. Contrary to that belief, this review unveils the impracticality of photocatalytic water splitting (solar energy for H2 energy) to fuel global advancement. Despite some success with idealized laboratory-scale studies, the past research works also mutually evinced an extreme low solar-to-hydrogen efficiency (STH < 1.0%). Hitherto, multifarious endeavours, such as advanced reactor design, facilities to eliminate diffusional restrictions, advanced photocatalyst design and an inclusion of sacrificial reagents, are incapable to raise STH efficiency to the practical threshold of STH > 10%. Regardless of the epitome and modifications of photocatalysts, the intrinsic limitation of charges recombination remains a sturdy obstacle, leading to an appreciable energy losses and low STH. For consequential solar-driven H2 production, the bandgap energy of photocatalyst employed must stay below 2.36 eV. Meanwhile, most photocatalysts are capped by the theoretical maximum STH of 18%, even with the assumption of 100% quantum yield of corresponding spectrum. Nonetheless, the theoretical maximum STH is unattainable at this juncture due to the inevitable solar energy dissipation associated to the scattering effects of reactor and water. From economy standpoint, H2 production via photocatalytic water splitting is pricey at 10.36 $/kg with exorbitant upfront costs, which is far beyond the practicable price range of 2 – 4 $/kg. In conclusion, we assert that the H2 production from solar-driven photocatalytic water splitting is an industrially impractical pathway for solar energy harnessing, despite technically-feasible.
Falling mixed-phase virga from a thin supercooled liquid layer cloud base were observed on 20 occasions at altitudes of 2.3–9.4 km with ground-based lidars at Wuhan (30.5 °N, 114.4 °E), China. ...Polarization lidar profile (3.75-m) analysis reveals some ubiquitous features of both falling mixed-phase virga and their liquid parent cloud layers. Each liquid parent cloud had a well-defined base height where the backscatter ratio R was ~7.0 and the R profile had a clear inflection point. At an altitude of ~34 m above the base height, the depolarization ratio reached its minimum value (~0.04), indicating a liquid-only level therein. The thin parent cloud layers tended to form on the top of a broad preexisting aerosol/liquid water layer. The falling virga below the base height showed firstly a significant depolarization ratio increase, suggesting that most supercooled liquid drops in the virga were rapidly frozen into ice crystals (via contact freezing). After reaching a local maximum value of the depolarization ratio, both the values of the backscatter ratio and depolarization ratio for the virga exhibited an overall decrease with decreasing height, indicating sublimated ice crystals. The diameters of the ice crystals in the virga were estimated based on an ice particle sublimation model along with the lidar and radiosonde observations. It was found that the ice crystal particles in these virga cases tended to have smaller mean diameters and narrower size distributions with increasing altitude. The mean diameter value is 350 ± 111 µm at altitudes of 4–8.5 km.
Nonlinear evolution equations are used to describe such nonlinear phenomena as the solitons, travelling waves and breathers in fluid mechanics, plasma physics and optics. In this paper, we ...investigate a (2＋1)-dimensional generalized nonlinear evolution system in a fluid or a plasma. Via the Lie symmetry analysis, we acquire the Lie point symmetry generators and Lie symmetry groups of that system. Via the optimal system method, we derive the optimal system of the 1-dimensional subalgebras. Based on the symmetry generators in that optimal system, we give some symmetry reductions for the (2＋1)-dimensional generalized nonlinear evolution system. Finally, via those symmetry reductions, we acquire some soliton, rational-type and power-series solutions.
•A (2+1)-dimensional generalized nonlinear evolution system is investigated.•The Lie symmetry analysis of the system is investigated.•Some symmetry reductions are derived.•Soliton solutions are obtained.
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