The presented study synthesized c:Se NPs via a combination of the laser along with magnetic field at various laser pulse energies 200, 600 and 1000mJ with 100 shots, have been deposited on the porous silicon (PS) thro...
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The presented study synthesized c:Se NPs via a combination of the laser along with magnetic field at various laser pulse energies 200, 600 and 1000mJ with 100 shots, have been deposited on the porous silicon (PS) through the use of drop-casting method. The pattern of the X-ray diffraction (XRD) had indicated the nanocrystaline of specimens. In Atomic force microscopy (AFM), which shows agglomeration of c:Se NPs increased, the distribution of the granularity showed that the distribution of part was almost Gaussian, also the transmission electron microscope (TEM) indicated that the synthesized c:Se particles have an average particle size of 35 nm. Bright-field TEM images show complementary contrast, confirming the formation of core/shell structures. The optical measurements in wavelength range ultraviolet-visible near infrared (UV-vis-NIR) as well as a transition of indirect type with 4 eV band gap is specified. Also, the electrical characteristics like barrier height (phi B), ideal factor (n) for Al/c:Se NPs/PS/Si/Al heterojunction were concluded with measurements of current-voltage (I-V). Lastly, the operation temperature variations associated with NO2 and NH3 gas sensors are subjected to fabrication from the prepared samples on response time, sensor sensitivity and recover time was examined. The maximum sensitivity of c:Se/PS at 1000 mJ gas sensor to 60 ppm of NO2 about 202.5% at around 100 degrees c, also the maximum sensitivity of c:Se/PS at 1000mJgas sensor to 200 ppm of NH3 can reach 17.9%, and the optimum sensing temperature of c: Se/PS sensor is at around 150 degrees c.
To operate the moving bed biofilm reactor inoculated with HN-AD bacteria (B-MBBR) instead of activated sludge for livestock and poultry breeding wastewater (LPBW) disposal in most efficient manner, nitrogen removal (N...
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To operate the moving bed biofilm reactor inoculated with HN-AD bacteria (B-MBBR) instead of activated sludge for livestock and poultry breeding wastewater (LPBW) disposal in most efficient manner, nitrogen removal (NR) efficiency and microbial composition of two MBBRs with different carrier types under various c/N ratios were explored. Results indicated that the performance on NR greatly various in different carrier types under various c/ N ratios. Attributing to the bacterial protection provided by the porous structure of polyvinyl alcohol (PVA) gel, MBBR using PVA gel as the carrier exhibited a more stable NR performance (range from 78.05% to 83.76%) versus that using Kaldnes (K1) as the carrier (range from 78.05% to 83.76%). Besides, microbial analysis indicated that MBBR with PVA gel as the carrier is conducive to the growth of oligotrophic and HN-AD bacteria (Paracoccus and Acinetobacter), and the highest relative abundance was 16.37% at c/N ratio of 6.
caenorhabditiselegans (c. elegans) has gained importance as a model for studying host-microbiota interactions and bacterial infections related to human pathogens. Assessing the fate of ingested bacteria in the worm...
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caenorhabditiselegans (c. elegans) has gained importance as a model for studying host-microbiota interactions and bacterial infections related to human pathogens. Assessing the fate of ingested bacteria in the worm's intestine is therefore of great interest, in particular with respect to normal bacterial digestion or intestinal colonization by pathogens. Here, we report an in vivo study of bacteria in the gut of c. elegans. We take advantage of a polydimethylsiloxane (PDMS) microfluidic device enabling passive immobilization of adult worms under physiological conditions. Non-pathogenic Escherichia coli (E. coli) bacteria expressing either pH-sensitive or pH-insensitive fluorescence reporters as well as fluorescently marked indigestible microbeads were used for the different assays. Dynamic fluorescence patterns of the bacterial load in the worm gut were conveniently monitored by time-lapse imaging. cyclic motion of the bacterial load due to peristaltic activity of the gut was observed and biochemical digestion of E. coli was characterized by high-resolution fluorescence imaging of the worm's intestine. We could discriminate between individual intact bacteria and diffuse signals related to disrupted bacteria that can be digested. From the decay of the diffuse fluorescent signal, we determined a digestion time constant of 14 +/- 4 s. In order to evaluate the possibility to perform infection assays with our platform, immobilized c. elegans worms were fed pathogenic Mycobacterium marinum (M. marinum) bacteria. We analyzed bacterial fate and accumulation in the gut of N2 worms and mitochondrial stress response in a hsp-6::gfp mutant.
The microalga c. vulgaris is a potential source for sustainable food ingredients and particularly food protein. Ultrasonication can enhance the extraction of proteins from chlorella, but a comprehensive comparison to ...
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The microalga c. vulgaris is a potential source for sustainable food ingredients and particularly food protein. Ultrasonication can enhance the extraction of proteins from chlorella, but a comprehensive comparison to other cell disintegration technologies is not possible since knowledge about the energy requirements is missing. In this article, the effects of an elevated static pressure up to 5 bar, sound amplitude, and treatment duration on energy consumption and protein extraction yield were explored. Elevating the static pressure affects the oscillation dynamics and collapses of cavitating bubbles and leads to more destructive collapses and higher energy. By employing numerical simulations of bubble oscillations, it was shown that the protein yield is mostly affected by the energy being radiated during the collapse of single bubbles and the total number of collapses during the treatment. Increasing the biomass concentration before sonication offers a way to further reduce the massspecific energy input.
Based on density functional theory calculations under the framework of first-principles, the electronic and optical characteristics of c2N/ZnTe van der Waals (vdW) heterostructure are investigated in detail. An inhere...
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Based on density functional theory calculations under the framework of first-principles, the electronic and optical characteristics of c2N/ZnTe van der Waals (vdW) heterostructure are investigated in detail. An inherent type-II band alignment arises in the heterostructure, which possesses a 1.94 eV direct band gap. With light irradiation, the photogenerated electron-hole pairs of heterostructure are separated on different monolayers. This helps to extending the lifetime of carriers. Additionally, the lower effective carrier mass (me*=0.55m0, mh*=0.23m0) is owned for the heterostructure. The heterostructure has suitable band gap and band edge positions, as well as, enhanced visible light absorption capacity, which can facilitate photocatalytic water splitting in acidicconditions. More interestingly, the redox reaction of photocatalytic water splitting can still proceed on the heterostructure after exerting a biaxial tensile strain of 2-6%. These results suggest that c2N/ZnTe vdW heterostructure will be a promising water splitting photocatalyst.
The surface microstructural evolution, mechanical properties and ablation behaviors of nitrogen-doped c/c-ZrcSiccomposites by hot isostatic pressing(HIP) have been studied via multiple-characterizations. Results show...
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The surface microstructural evolution, mechanical properties and ablation behaviors of nitrogen-doped c/c-ZrcSiccomposites by hot isostatic pressing(HIP) have been studied via multiple-characterizations. Results show that the post-treatment of nitridation has significant effects on mechanical strength with grain refinement by virtue of in-situ SEM observations. After nitridation, the dense nano-grained ZrO/Zr2O and Si3N4 ceramics are generated on the top layer. Besides, the evident carbon nanowires exist at boundary of Sic-Si3N4 phases. The ZrN/Si3N4 eutectic structures are also detected with the transformation of ZrSi phase. What's more, the ablation-resistant performances are strikingly improved after nitridation-treatment with the highly compact multi-oxide scales obtained.
To obtain unbroken sulfides with delicate morphology from metal-organic frameworks (MOFs), a method for in situ growth of SiO2 protective layers on the surface of MOFs is proposed. This strategy can be successfully ex...
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To obtain unbroken sulfides with delicate morphology from metal-organic frameworks (MOFs), a method for in situ growth of SiO2 protective layers on the surface of MOFs is proposed. This strategy can be successfully expanded to a variety of MOFs (ZIF-67, cu-MOF, ZIF-8, and PBA). Importantly, room-temperature Na-SeS2 batteries with co9S8@SiO2/c prepared from ZIF-67 as cathode host are assembled. Due to the hollow structure that can relieve the volume expansion and the co-adsorption of sodium polysulfides/sodium polyselenides by co9S8@SiO2/c, the SeS2/co9S8@SiO2/ccathode shows excellent rate performance and coulombic efficiency. In addition, ex situ X-ray diffraction and in situ Raman results show that S-8 and Se-8 are generated after the discharge of SeS2, and Se-8 is preferentially oxidized during charging.
The influence of cr and Al content on the oxidation behaviour of Fecr(Al) model alloys after breakaway oxidation at 600 degrees c and the underlying mechanisms were investigated in detail with thermogravimetrical anal...
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The influence of cr and Al content on the oxidation behaviour of Fecr(Al) model alloys after breakaway oxidation at 600 degrees c and the underlying mechanisms were investigated in detail with thermogravimetrical analysis (TGA), thermodynamiccalculations and advanced electron microscopy. The results showed that a crcontent of >18 wt% drastically reduced the growth rate of the Fe-rich oxide scale, formed after breakaway oxidation, for FecrAl alloys but not for Fecr alloys. This was attributed to the ability of the Fe(18-25)crAl alloys to prevent internal oxidation, which enables the formation of a healing layer.
Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate...
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Microplastics (MPs) are distributed in a wide range of aquatic and terrestrial ecosystems throughout the planet. They are known to adsorb hazardous substances and can transfer them across the trophic web. To eliminate MPs pollution in an environmentally friendly process, we propose using a photocatalytic process that can easily be implemented in wastewater treatment plants (WWTPs). As photocatalysis involves the formation of reactive species such as holes (h(+)), electrons (e(-)), hydroxyl (OH?), and superoxide ion (O-2(?-)) radicals, it is imperative to determine the role of those species in the degradation process to design an effective photocatalytic system. However, for MPs, this information is limited in the literature. Therefore, we present such reactive species' role in the degradation of high-density polyethylene (HDPE) MPs using c,N-TiO2. Tert-butanol, isopropyl alcohol (IPA), Tiron, and cu(NO3)(2) were confirmed as adequate OH?, h(+), O-2(?-) and e(-) scavengers. These results revealed for the first time that the formation of free OH? through the pathways involving the photogenerated e(-) plays an essential role in the MPs' degradation. Furthermore, the degradation behaviors observed when h(+) and O-2(?-) were removed from the reaction system suggest that these species can also perform the initiating step of degradation.
We demonstrated the efficient coupling of BiFeO3 (BFO) ferroelectric material within the carbon-sulfur (c-S) composite cathode, where polysulfides are trapped in BFO mesh, reducing the polysulfide shuttle impact, and ...
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We demonstrated the efficient coupling of BiFeO3 (BFO) ferroelectric material within the carbon-sulfur (c-S) composite cathode, where polysulfides are trapped in BFO mesh, reducing the polysulfide shuttle impact, and thus resulting in an improved cyclic performance and an increase in capacity in Li-S batteries. Here, the built-in internal field due to BFO enhances polysulfide trapping. The observation of a difference in the diffusion behavior of polysulfides in BFO-coupled composites suggests more efficient trapping in BFO-modified c-S electrodes compared to pristine c-S composite cathodes. The X-ray diffraction results of BFO-c-S composite cathodes show an orthorhombic structure, while Raman spectra substantiate efficient coupling of BFO in c-S composites, in agreement with SEM images, showing the interconnected network of submicron-size sulfur composites. Two plateaus were observed at 1.75 V and 2.1 V in the charge/discharge characteristics of BFO-c-S composite cathodes. The observed capacity of ~1600 mAh g(-1) in a 1.5-2.5 V operating window for BFO30-c-10-S-60 composite cathodes, and the high cyclic stability substantiate the superior performance of the designed cathode materials due to the efficient reduction in the polysulfide shuttle effect in these composite cathodes.
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