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Flexible fluorinated multi-walled carbon nanotube/polyarylene ether nitrile porous metacomposite film (FMWCNT/PEN) with negative permittivity has been fabricated via a delayed phase inversion method with a low content of FMWCNT.

Asymmetric functionalization of the C(sp3)-H bond is an attractive yet challenging strategy to achieve versatile bond-forming events, enabling the precise assembly of molecular complexity with minimal manipulation of functional groups. Here, we report an asymmetric C(sp3)-H/C(sp3)-H umpolung coupling of N-allylimine and coordinating α-aryl carbonyls by using chiral phosphoramidite-palladium catalysis. A wide variety of α-heteroaryl ketones and 2-acylimidazoles are nicely tolerated to open a convenient and tunable avenue for efficient synthesis of enantioenriched β-amino-γ,δ-unsaturated carbonyl derivatives with high levels of regio- and stereoselectivities, capable of providing a key intermediate for asymmetric synthesis of Focalin. This protocol showcases an umpolung reactivity of the N-allylimines through a concerted proton and two-electron transfer process to cleave the allylic C-H bond, effectively complementing established methodology for allylic C-H functionalization. An inner-sphere allylation pathway for both α-heteroaryl carbonyls and 2-acylimidazoles to attack the π-allylpalladium species is suggested by computational studies and experimental facts, wherein the nitrogen coordination to the palladium center enables the preference of branched regioselectivity.

Background Massive hemoptysis due to aspergilloma is a rare but life-threatening complication. Bronchial artery embolization is recommended as a definitive treatment for massive hemoptysis. Polyvinyl alcohol is widely used in bronchial artery embolization. A very small number of studies have reported disrupted polyvinyl alcohol, which may cause ectopic embolism. Case presentation This case highlights an unusual phenomenon in which polyvinyl alcohol fragments appeared on pathological examination in a 61-year-old man, ethnic Han, with massive hemoptysis caused by aspergilloma for whom bronchial artery embolization failed. Lobectomy was carried out successfully. Hematoxylin and eosin stain provides clear images of polyvinyl alcohol fragments, while alpha-smooth muscle cell actin and cluster of differentiation-34 immunohistochemistry revealed their localization in bronchioles. Conclusion Thus far, only two cases of polyvinyl alcohol fragments in the lung have been reported, and the mechanism has not been elucidated. These two cases revealed no counter-indication for the use of polyvinyl alcohol. However, in some cases of off-target embolization causing fatal complications, such as stroke, paraplegia, and myocardial, polyvinyl alcohol fragmentation needs to be taken into consideration.

Background Searching for and developing green corrosion-resisting drugs plays an significant role in protecting Cu during its pickling treatment. The toxicities and inhibitive performances are closely correlated with their molecular formulas. Methods Therefore, Amoxapine, Loxapine and Clozapine, all of which belong to piperazines, were assessed as inhibitive agents to protect Cu from corrosion in 0.5 M H2SO4 via electrochemical measurements, surface morphologies and theoretical calculations. According to the electrochemical results, the anti-corrosion efficiencies of AP, LP and CP reached their maximums at 5 mM, namely 94.0༅, 95.2༅ and 96.6༅, respectively. They were all proved to be cathodic-type corrosion inhibitors. The morphology analysis implied the shaping of protective films on Cu surfaces. Moreover, the absorption of AP, LP and CP on Cu surfaces deferred to the Langmuir isotherm model, confirming the analysis of Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Theoretical calculations revealed their adsorption models and anti-corrosive mechanisms. Significant Findings Both experiment and calculation manifested favourable corrosion-proof properties of the three researched drugs. Further analysis also proved the enhanced inhibitive effect of methyl that connected with benzene ring owing to its conjugative effect. Furthermore, N atom possessed higher electronegativity and accordingly stronger electron-donating ability compared to O atom. The corrosion-resisting efficiency of Clozapine was 96.6%, being higher than that of Loxapine which was 95.2%.

NK-lysin, an effector of natural killer (NK) cells and cytotoxic T lymphocytes (CTLs), not only exhibits cytotoxic effect in fish cells, but also participates in the immune defense against pathogenic infection. In this study, ORF sequences of RCC-NK-lysin, WCC-NK-lysin and WR-NK-lysin were 369 bp. Tissue-specific analysis revealed that the highest expressions of RCC-NK-lysin and WCC-NK-lysin were observed in gill, while the peaked level of WR-NK-lysin mRNA was observed in spleen. A. hydrophila infection sharply increased RCC-NK-lysin, WCC-NK-lysin and WR-NK-lysin mRNA expression in liver, trunk kidney and spleen. In addition, elevated levels of NK-lysin mRNA were observed in cultured fin cell lines of red crucian carp (RCC), white crucian carp (WCC) and their hybrid offspring (WR) after Lipopolysaccharide (LPS) challenge. RCC-NK-lysin, WCC-NK-lysin and WR-NK-lysin exerted regulatory roles in inducing ROS generation, modulating mitochondrial membrane potential, decreasing fish cell viability and antagonizing survival signalings, respectively. RCC/WCC/WR-NK-lysin-overexpressing fish could up-regulate expressions of inflammatory cytokines and decrease bacterial loads in spleen. These results indicated that NK-lysin in hybrid fish contained close sequence similarity to those of its parents, possessing the capacities of cytotoxicity and immune defense against bacterial infection.

Background One of the greatest challenges for tissue-engineered bone is the low survival rate of locally grafted cells. The cell homing technology can effectively increase the number of these grafted cells, therefore, enhancing the repair of bone defects. Here we explore the effect of fucosylation modification on the directional homing of bone marrow mesenchymal stem cells (BMSCs) and their ability to repair bone defects. Results Glycosylated BMSCs expressed high levels of the Sialyl Lewis-X (sLeX) antigen, which enabled the cells to efficiently bind to E- and P-selectins and to home to bone defect sites in vivo. Micro-CT and histological staining results confirmed that mice injected with FuT7-BMSCs showed an improved repair of bone defects compared to unmodified BMSCs. Conclusions The glycosylation modification of BMSCs has significantly enhanced their directional homing ability to bone defect sites, therefore, promoting bone repair. Our results suggest that glycosylation-modified BMSCs can be used as the source of the cells for the tissue-engineered bone and provide a new approach for the treatment of bone defects. Graphic Abstract

Molybdenum trioxide (MoO3) is regarded as a promising electrode material for lithium (Li)-ion batteries because of its unique layered structure with a high theoretical capacity (~ 1117 mAh·g−1). Till now, numerous researches have focused on tuning MoO3 morphology to improve its electrochemical performance. However, the fabrication of MoO3 with a two-dimensional (2D) nanosheet clusters structure has yet been achieved. Here, we report a facile one-step solvothermal method to prepare MoO3 nanosheets, of which the morphology can be facilely tuned via the dose of hydrogen peroxide. Both the experimental results and theoretical calculation suggest that the resultant 2D nanosheets structure could reduce the diffusion paths, which is beneficial for the intercalation of Li-ion. As a result, the nanosheets assembled Li-ion battery has a reversible specific capacity of 756.1 mAh·g−1 at 0.5 A·g−1, and maintained at 214.7 mAh·g−1 after 600 cycles at a current density of 1 A·g−1 with the Coulombic efficiency as high as 97.17%.

The electrocatalysis of nitrate reduction reaction (NRR) has been considered to be a promising nitrate removal technology. Developing a highly effective iron-based electrocatalyst is an essential challenge for NRR. Herein, boron-iron nanochains (B-Fe NCs) as efficient NRR catalysts were prepared via a facile low-cost and scalable method. The Fe/B ratio of the B-Fe NCs-x can be elaborately adjusted to optimize the NRR catalytic performance. Due to the electron transfer from boron to metal, the metal-metal bonds are weakened and the electron density near the metal atom centers are rearranged, which are favor of the conversion from NO3− into N2. Moreover, the well-crosslinked chain-like architectures benefit the mass/electron transport to boost the exposure of abundant catalytic active sites. Laboratory experiments demonstrated that the optimized B-Fe NCs catalyst exhibits superior intrinsic electrocatalytic NRR activity of high nitrate conversion (∼80%), ultrahigh nitrogen selectivity (∼99%) and excellent long-term reactivity in the mixed electrolyte system (0.02 mol/L NaCl and 0.02 mol/L Na2SO4 mixed electrolyte), and the electrocatalytic activity of the material shows poor performance at low chloride ion concentration (Nitrate conversion of ∼61% and nitrogen selectivity of ∼57% in 0.005 mol/L NaCl and 0.035 mol/L Na2SO4 mixed electrolyte). This study provides a broad application prospect for further exploring the high-efficiency and low-cost iron-based functional nanostructures for electrocatalytic nitrate reduction.

We presented and demonstrated a new type of vertical nanowire (NW) and nanosheet (NS) field-effect transistors (FETs), named vertical sandwich gate-all-around FETs or VSAFETs, which were formed with the process compatible in the main stream industry. The VSAFETs with self-aligned high- ${k}$ metal gates (HKMGs) were fabricated with epitaxy of Si/SiGe/Si sandwich structure, an isotropic quasi-atomic-layer-etch (qALE) process, and gate replacement process. The gate-length of VSAFETs is mainly determined by the thickness of SiGe film grown by epitaxy. The NW diameter and NS thickness could be obtained by the isotropic qALE method, which can be used to the Si-selective etching of SiGe. As a result, p-type NS and NW VSAFETs with good device characteristics were fabricated. Device performance and the influence of silicide, Ge fraction, Si cap, and high thermal process were investigated; threshold voltage tuning and reliability were also discussed.

The development of new tools that could meet the demand of sustainable energy production has attracted worldwide scientific attention. Over the past few decades, significant research efforts have been carried out to efficiently reduce water to H2 (green fuel) over semiconductor photocatalysts. Numerous semiconductor photocatalysts have been employed in photocatalysis for optimum H2 production. All the techniques were chosen based on their flexibility, cost-effectiveness, and ease of availability. Recently, polymeric carbon nitride (g-C3N4) received worldwide attention in visible light photocatalysis for energy and environmental applications due to its low price, robust nature, and superior thermal stability. Nevertheless, g-C3N4 (CN) exhibits shortfalls such as high charge carrier's recombination rate and weak reduction ability. To overcome these drawbacks, herein, for the first time we have fabricated B-TiO2/MIL-53(Fe)/CN ternary composite via hydrothermal and wet-chemical methods. The resultant B-TiO2/MIL53(Fe)/CN ternary composite shows drastically improved photocatalytic activity for hydrogen evolution compared to the bare CN, B-TiO2, and MIL53(Fe) components. The B-TiO2/MIL53(Fe)/CN ternary composite produced approximately 166.3 and 581.2 μmol h−1 g−1 of hydrogen under visible light and UV–visible light irradiations, respectively, with the assistance of co-catalyst Pt. Photo-luminescence (PL) and the fluorescence (FL) spectroscopy measurements reveal that the enhanced photoactivity is due to the greatly promoted charge carrier's separation and transfer at the interfacial contact of the well-aligned three-component systems. This work will promote the design and development of efficient photocatalyst based on CN for clean energy production and environmental purification.

To realize highly efficient hydrogen production of graphene-based photocatalysts, it is greatly important to increase more interfacial active sites onto graphene. In this work, the highly efficient CoSx-rGO (reduced graphene oxide)/TiO2 composite photocatalyst was synthesized via a simple two-step method, including the hydrothermal loading of rGO nanosheets onto TiO2 nanoparticles and the subsequent photodeposition process of CoSx nanodots (0.5–2 nm) on the rGO nanosheets. Photocatalytic experimental results confirmed that the CoSx-rGO/TiO2 photocatalyst displayed a distinctly higher photocatalytic H2-evolution activity than the TiO2 photocatalyst. The highest hydrogen-production efficiency of obtained CoSx-rGO/TiO2 (10%) achieved 256.97 μmol·h−1, which was distinctly higher than that of TiO2 (4.41 μmol·h−1), rGO/TiO2 (20.19 μmol·h−1) and CoSx/TiO2 (132.67 μmol·h−1). According to the results of various characterizations and tests, the synergistic-effect mechanism of CoSx nanodots and rGO nanosheets is proposed to explain the increased photocatalytic performance of CoSx-rGO/TiO2 photocatalytic material, namely the rGO nanosheets cause the quick transfer of photo-induced carriers from TiO2 to CoSx nanodots, and then CoSx nanodots work as hydrogen-production active sites to quickly generate H2. The present study may offer innovative ideas for the preparation and application of new highly efficient and inexpensive photocatalytic materials. 增加石墨烯界面产氢活性位点是提升石墨烯基光催化材料的一种重要方法。在本研究中, 通过简单的两步法合成了高效的CoSx-rGO/TiO2复合光催化剂, 即首先利用水热法将rGO纳米片负载到TiO2纳米颗粒上, 随后再通过光沉积的方法在rGO纳米片表面沉积CoSx纳米点 (0.5–2 nm)。光催化实验结果表明, 光催化剂CoSx-rGO/TiO2相比于TiO2具有更高的光催化析氢活性。其中CoSx-rGO/TiO2(10%) 光催化剂的产氢性能达到256.97 μmol•h-1, 明显高于TiO2 (4.41 μmol•h-1)、rGO/TiO2 (20.19 μmol•h-1)和CoSx/TiO2(132.67 μmol•h-1)。根据各种表征测试结果, 提出了CoSx纳米点和rGO纳米片协同增强TiO2光催化产氢性能的作用机理, 即rGO纳米片作为良好的电子转移介质可以将TiO2上的光生电子快速转移至CoSx, 随后CoSx纳米点作为产氢活性位点快速产生H2。本研究可以为新型高效光催化材料的制备和应用提供新的思路。

In-situ catalytic pyrolysis has simple process configuration and low cost. Ex-situ catalytic pyrolysis can optimize the pyrolysis capacity and upgrade catalysis, and the catalytic can be reused. But there have been few studies researched on compare in-situ and ex-situ catalytic pyrolysis of the OS performed in similar reactor with two kinds of catalytic. This paper study the pyrolysis of oily sludge (OS) uses CaO and oily pyrolysis char as catalytic at 700 °C. Through analysis the pyrolysis oil (PO), pyrolysis solid (PS) and pyrolysis gas (PG) during pyrolysis procedure to research the difference between in-situ and ex-situ catalytic pyrolysis. The gas chromatography-mass spectrometry (GC-MS) results show that CaO was conducive to the synthesis of aromatics, which content more than aliphatics and heterocyclics in CaO-i (i: in-situ) and CaO-e (e: ex-situ) groups. However, char greatly inhibits the production of aromatic compounds and promotes the production of aliphatic compounds. Gas chromatography (GC) results present that the char and CaO can greatly increase the content of combustible gas and the content reach to 85.85%, the pyrolysis gas (PG) keep at the highest combustion performance in char-CaO-i group. Meanwhile, compared with uncatalyzed groups, the content of CH4 and CO increased about 2.05% and 3.93%, respectively. Fourier transform infrared spectroscopy (FT-IR) show that char and CaO reduce the function groups number of pyrolysis solid (PS), and it shows that the pyrolysis reaction is more complete. This research is expecting to provide theory support for catalytic pyrolysis of OS.

The propensity of acid corrosion for X65 steel substrate leads to application restrictions. In this research, we develop an efficient and new corrosion inhibitor, S-(benzo[d]thiazol-2-yl) (E)-2-(2-aminothiazol-4-yl)-2-(methoxyimino)ethanethioate (BTAE), as a first example of a sulfuric acid medium additive containing both benzothiazole and aminothiazole with multiple anchoring centers, which can inhibit the X65 corrosion in the sulfuric acid medium. The electrochemical experiment test shows that BTAE can effectually control the anodic reaction of X65 steel and belongs to the anodic type corrosion inhibitor. The corrosion inhibition efficiency of BTAE can still be maintained above 97% within a certain temperature range. The surface topography analysis and electrochemical test results are highly consistent. The adsorption of BTAE onto the interface of X65 steel conforms to the Langmuir model. Quantum chemistry and molecular dynamics simulation results have proved that BTAE is an excellent corrosion inhibitor.

The assembly of monomicelles along one-dimension (1D) to construct tubular or fibrous mesostructures is greatly desired but still challenging. Herein, we have demonstrated a facile strategy to synthesize 1D bimodal mesoporous metal oxides (e.g., WO3, WO3/Pd, WO3/PdCu, TiO2, and ZrO2) nanofibers (NFs) through assembling the organic-inorganic composite monomicelles in a beam stream generated via an electrospinning technique. This facile and repeatable methodology relies on the preparation of copolymer@metal-complex monomicelles in an anisotropic solution and oriented assembly of them in the beam stream by the selective evaporation of solvent. WO3 and its derivatives are chosen as the demo, which show a uniform continuous fibrous structure with dual mesopore sizes (∼4.0 and 7.6 nm) and large surface area (∼93.1 m2 g−1). Benefitting from the unique textual structure, gas sensors made by Pd-decorated mesoporous WO3 NFs display outstanding comprehensive sensing performance to ethylbenzene, including a high sensitivity (52.5), an ultralow detection limit (50 ppb), and fast response/recovery kinetics (11/16 s) as well as an outstanding selectivity, which render them promising for rapid environmental monitoring.

Fundamental understanding of the size effects of Pt-electrocatalyzed methanol oxidation reaction (MOR) in the alkaline media is rarely explored, especially from the viewpoint of catalyst active sites. Herein, we report a remarkable size-dependent MOR activity of atomic-layer-deposited Pt nanoparticles on CNT. The surface properties of CNT are tailored, and using the growth temperature of 600 °C followed by the oxidation treatment is found to yield an attractive support, i.e., CNT-600-O, for the fabrication of highly active Pt catalysts. On such support, the 1.9 nm sized Pt catalyst gives rise to the highest peak current density, which is approximately 3.2 times higher than the commercial Pt/C catalyst. The underlying nature of the Pt size effects is further elucidated by the model calculations together with HRTEM and XPS measurements. The Pt corner sites are discriminated as the dominant active sites, and the lower Pt° 4f binding energy favors the reaction. The insights revealed here could shed light on the fabrication of highly efficient Pt-based MOR catalyst by tailoring the quantity and quality of the catalyst active sites.

This paper aims to evaluate the effect of low-cost clays (kaolin with different particle size and montmorillonite (MTT) modified with ZnCl2 and HCl) as catalysts on the pyrolysis products from waste tire. The results show that clays can improve the quality and yield of pyrolysis products. Different particle size and modification conditions have significant influence on the distribution and component of pyrolysis products. Compared with blank group, the content of combustible gas (including CH4 of 56.35%, H2 of 35.67% and CO of 7.98%) in ZnCl2 group is increased. Moreover, the hydrocarbon content of pyrolysis oil in each group exceed 90%. The N-containing compounds can be removed by hydrodenitrogenation (HDN) reaction and convert into aromatics through ring-opening reaction. Meanwhile, the yield of the O-containing compounds in each group is less than 3%, and the lowest content is ZnCl2 group. ZnCl2-modified MTT have high specific surface area and rich mesoporous structure, which can promote deoxidation and aromatization to reach the highest aromatics content (90.23%). In addition, the content of C11–C20 in addition groups can be increased by small molecule polymerization. The catalysts promote the formation of diesel fraction through alkylation of benzene and naphthalene.

The intracellular NADPH insufficient supply is the main bottleneck to the synthesis of chiral alcohols by asymmetric reduction with whole-cell catalysis. Herein, we provide a novel strategy to strengthen intracellular NADPH supply through introducing an NADP+-dependent glyceraldehyde 3-phosphate dehydrogenase (gapB from Bacillus subtilis 168) into the Embden-Meyerhof pathway and a NAD kinase (yfjB from E. coli MG1655) to further enhance the NADP(H) pool. A recombinant E. coli (E. coli BL21 (DE3)/pETDuet-1-gapB-yueD&pET28a-yfjB) was constructed to co-express gapB and yfjB with a carbonyl reductase gene yueD together. The result showed that the intracellular NADPH amount increased by 134.4% with the strategy. To the model reaction (asymmetric reduction of acetophenone to S-phenyl ethanol), the yield was 3.7-fold with this strategy compared to the control. This provides a technological route for strengthening the intracellular NADPH supply in E. coli for biocatalysis and biosynthesis.

Organic reactions using metal–organic frameworks (MOFs) as catalysts are promising with regard to their environmentally friendly features and potential catalyst recyclability. A robust Co(II)-MOF {[Co2(L-mac)(4,4-bpt)(H2O)]·3.5H2O}n (1) and its enantiomer {[Co2(D-mac)(4,4-bpt)(H2O)]·3.5H2O}n (2) (L/D-mac = basic forms of L/D-malic acid, 4,4-Hbpt = 3,5-di(pyridin-4-yl)-4H-1,2,4-triazole) have been gram-scale prepared under solvothermal conditions. Structural analysis reveals that mac manages Co(II) ions to form 1-D chains, which are further extended via 4,4-bpt connectors into a noninterpenetrating 3D framework architecture. It was found that 1 can be as a heterogeneous catalyst for multiple organic reactions, such as azide-alkyne cycloaddition and Friedel–Crafts reactions with good isolated yields and good recycle runs (at least five times without substantial degradation). Additionally, 1 can promote hydrosilylation of alkynes under harsh conditions with moderate yield.

This preliminary study aimed to compare the application of pulsed electric field (PEF) with a traditional blanching as pre-treatments before frying for the mitigation of acrylamide content in potato crisps. Measuring the degree of cell disintegration index (po) and the changes in water electrical conductivity during washing of potato slices, PEF protocol and sample preparation scheme were optimized. Peeled potato slices (thickness 1.5 ± 0.2 mm) were subjected to PEF (1.5 kV/cm, pulse duration 10 μs, total treatment time 10 ms, pulse frequency 100 Hz) and to blanching (85 °C for 3.5 min) pre-treatments and then to washing in water, evaluating the reduction of acrylamide precursors (reducing sugars and free asparagine). After frying (175 °C, 3 min), product quality, in terms of colour, texture and acrylamide content were evaluated. Results showed that PEF promoted acrylamide precursors leaching followed by a reduction of the final acrylamide content of around 30%, significantly higher if compared to the reduction obtained with blanching, with only slight modifications of the final quality of the product, in terms of colour and texture. Industrial relevance The Commission Regulation (EU) 2017/2158 of 20 November 2017 has introduced new benchmark levels and mitigation strategies for the reduction of the presence of acrylamide in foods, directing food businesses to the research of measures to lower the acrylamide formation in foods. The actual industrial production process of fried potato crisps involves the use of many mitigation strategies, such as a blanching of raw potatoes. However, the traditional blanching treatment presents several practical drawbacks and leads to undesirable changes of the product quality. The application of PEF as a pre-treatment could reduce the acrylamide content in deep-fat fried potato crisps. This preliminary study gives important indications regarding the possibility of combining a PEF pre-treatment on raw potato slices with subsequent industrial processing steps for the production of potato crisps with low acrylamide concentration.

Monoacetin was synthesized using a novel green method in which acetonitrile was hydrolyzed and then esterified with glycerol over Cu-Cr phosphates under the CO2 atmosphere. Monoacetin was synthesized with high yield (87.6% glycerol conversion and 86.3% monoacetin selectivity) through this one-pot cascade method. In this process, acetonitrile can react with water to form acetamide and further undergo esterification with glycerol. There are two main reasons for obtaining monoacetin in high yield: (1) the interaction of CO2 with high-temperature liquid water enhances the acid strength of the reaction system and then promotes the activation of acetonitrile; and (2) the introduction of Cr species causes a synergistic effect between Cu and Cr species to adjust the acidity and basicity of the catalyst. The introduction of Cr species converts eight-coordinated Cu2+ into four-coordinated Cu2+ to improve the acidity of the catalyst. The introduction of Cr species also causes the surface oxygen to be transformed into lattice oxygen to enhance the basicity of the catalyst. These bimetallic phosphate materials may provide a new pathway for the application of acid-base bifunctional catalytic reactions.

Marine Pollution Convention has been updated to prevent the excessive emissions from diesel machine. For high concentrated, large fluxed SO2 and NO photocatalytic oxidation, a novel dual stages oxidation-scrubbing process was proposed. The p–n junction ZnO-CuO/rGO ternary catalysts were prepared via the co-precipitation route and supported on reduced graphene oxide (rGO). The UV–vis spectra showed that the bandgap Eg of ZnO-CuO/rGO was notably narrowed to 2.3–2.6 eV for facilitating electron transfer, and its flat band potential of was −0.54 V versus Ag/AgCl. The PL spectra and photocurrent curves revealed that the formation of heterojunctions and the introduction of graphene promoted an efficient separation of the photo-induced charge carriers. The photocatalytic activity of the ZnO-CuO/rGO with 5 wt% GO was evaluated for simultaneous DeSOx and DeNOx, and 97% desulfurization rate and 64% denitration rate could be reached under GHSV 2000 h−1 for 270 min. In seawater scrubber, ZnO-CuO/rGO(5%) addition made SO32− conversion was 80.72%. The radical scavenging experiments demonstrated that holes (h+) and superoxide radicals (•O2−) contributed most to SO32− photocatalytic oxidation. Kinetic studies showed that SO32− oxidation on ZnO-CuO/rGO fitted the L-H model. The mechanism of photocatalytic oxidation in gas and liquid phases were also proposed to address the reaction pathway.

Reworked synthetic polymers (RSPs) are industrial raw materials obtained from waste synthetic polymer (WSP) through physical or chemical means. Different reworked synthetic polymers have different pyrolysis characteristics and synergistic reactions during co-pyrolysis process. The effect of reworked polyamide 6 (PA6), thermoplastic elastomer (TPE), black polypropylene (PP1) and green polypropylene (PP2) co-pyrolysis on the yield and quality of pyrolysis products has been conducted. The results show that co-pyrolysis promotes the degradation of RSPs into more gases. Co-pyrolysis improves the light component of liquid oils and reduces the O content, which is beneficial for liquid fuels. Except for TPE + PP2, co-pyrolysis of RSPs increased di-aromatics, poly-aromatics and aromatic compounds. TPE + PP2 and PP1+PP2 produced high aliphatic compounds including the long chain aliphatic compounds without sufficient degradation, which resulted in the contents of over C20 were high. In the pyrolysis gases, the relative content of H2 was increased in all mixed RSPs co-pyrolysis, which can be used as clean fuels. The X-ray diffraction (XRD) analysis shown that new components were found and old components disappeared in co-pyrolysis, indicating chemical reaction had occurred between two different types of RSPs.

Derivatives based on anthryleno[1,2-b]pyrazine-2,3-dicarbonitrile (DCPA) are used as luminescent materials, to realize near-infrared (NIR) electroluminescence. By functionalizing DCPA with aromatic amine donors, two emitters named DCPA-TPA and DCPA-BBPA are designed and synthesized. Both molecules have large dipole moments owing to the strong intramolecular charge transfer interactions between the amine donors and the DCPA acceptor. Thus, compared with doped films, the emission of neat films of DCPA-TPA and DCPA-BBPA can fully fall into the NIR region (>700 nm) with increasing surrounding polarity by increasing doping ratio. Moreover, the non-doped devices based on DCPA-TPA and DCPA-BBPA provide NIR emission with peaks at 838 and 916 nm, respectively. A maximum radiance of 20707 mW Sr-1 m-2 was realized for the further optimized device based on DCPA-TPA. This work provides a simple and efficient strategy of molecular design for developing NIR emitting materials.

Benzoic acid (BA) is an important platform aromatic compound in chemical industry and is widely used as food preservatives in its salt forms. Yet, current manufacture of BA is dependent on petrochemical processes under harsh conditions. Here we report the de novo production of BA from glucose using metabolically engineered Escherichia coli strains harboring a plant-like β-oxidation pathway or a newly designed synthetic pathway. First, three different natural BA biosynthetic pathways originated from plants and one synthetically designed pathway were systemically assessed for BA production from glucose by in silico flux response analyses. The selected plant-like β-oxidation pathway and the synthetic pathway were separately established in E. coli by expressing the genes encoding the necessary enzymes and screened heterologous enzymes under optimal plasmid configurations. BA production was further optimized by applying several metabolic engineering strategies to the engineered E. coli strains harboring each metabolic pathway, which included enhancement of the precursor availability, removal of competitive reactions, transporter engineering, and reduction of byproduct formation. Lastly, fed-batch fermentations of the final engineered strain harboring the β-oxidation pathway and the strain harboring the synthetic pathway were conducted, which resulted in the production of 2.37 ± 0.02 g/L and 181.0 ± 5.8 mg/L of BA from glucose, respectively; the former being the highest titer reported by microbial fermentation. The metabolic engineering strategies developed here will be useful for the production of related aromatics of high industrial interest.

Recently, graphene oxide (GO), MXene, carbon nanotubes (CNTs) have been used for compounding with other materials as anodes and cathodes to achieve excellent electrochemical properties for metal-ion batteries. However, few researches have focused on the differences between the three additives. Herein, silicon, as a typical anode, is selected to integrate with MXene, GO and CNTs in carbon nanofibers (CNFs) and form Si/MXene@CNFs, Si/GO@CNFs and Si/CNTs@CNFs, respectively. Together with the results, it can be realized that these CNFs with a significant improved performance compared with pure Si@CNFs show superiority in different aspects of electrochemical properties. Additionally, the reasons for the superiority are also discussed in this work. The addition of MXene can improve the cycle stability of the electrodes, thereby obtaining a high capacity retention rate, CNTs are favorable for the enhancement of rate performance, and the electrodes reversible capacity can be increased due to the addition of GO. Consequently, the studies on three additives may contribute to the rational design of silicon-based and other anode materials.

Heteroatom-doping of carbocatalysts has been a powerful strategy to remarkably enhance the catalytic performance. Herein, the underlying nature of N promotional effects on peroxymonosulfate (PMS) activation for phenol removal is understood by combining kinetics analysis with multiple techniques. A strategy using mixed acid oxidation of carbon nanotube (CNT) followed by NH3 treatment is employed to yield a series of catalysts with different N-doping contents but similar fraction of sp2-hybridized carbon and defective degree, endowing with a chance to discriminate the dominant N-containing active sites. The multi-sites kinetics analysis suggests the graphitic N-containing sites as the dominant active sites. The mechanism of the surface-bound reactive species is also discriminated as the dominant reaction mechanism. The insights reported here could provide the methodology to fundamentally understand the heteroatom-doping effects of carbocatalysis.

With ethyl orthosilicate as precursor and trimethylchlorosilane as surface modifier, hydrophobic SiO2 aerogels are prepared through sol–gel process combined with ambient pressure drying process. The influence law of different hydrolysis times on microstructure and physicochemical properties of aerogels when the reaction precursor is in the sol phase is studied. The results show that the hydrolysis time increases from 6 to 36 h, and the prepared aerogels have nanoscale mesoporous structure and hydrophobic properties. With the increase in hydrolysis time, the porosity and specific surface area of the samples increase and then decrease, and the density decreases and then increases, all of which reach their peaks at 18 h. The properties of samples are optimal after being hydrolyzed for 18 h. The prosperity is 96%, specific area is 1539.7706 m2/g, the density is 0.08921 g/cm3, and the contact angle is 148.3°.

Background: Arginase I, encoded by the ARG1 gene, is an enzyme that catalyzes the conversion of arginine to ornithine in the urea cycle; mutations in this gene has recently been reported to be asso...

Mg secondary batteries are promising scalable secondary batteries for next-generation energy storage. However, Mg-storage cathode materials are greatly demanded to construct high-performance Mg batteries. Electrochemical conversion reaction provides plenty of cathode options, and strategy for cathode selection and performance optimization is of special significance. In this work, Ni0.85Se with nanostructures of dispersive hexagonal nanosheets (D-Ni0.85Se) and flower-like assembled nanosheets (F-Ni0.85Se) is synthesized and investigated as Mg-storage cathodes. Compared with F-Ni0.85Se, D-Ni0.85Se delivers a higher specific capacity of 168 mAh g‒1 at 50 mA g‒1 as well as better rate performance, owing to its faster Mg2+ diffusion and lower resistance. D-Ni0.85Se also exhibits a superior cycling stability over 500 cycles. An investigation on mechanism indicates an evolution of Ni0.85Se towards NiSe with cycling, and the Mg-storage reaction occurs between NiSe and metallic Ni0. The present work demonstrates that advanced conversion-type Mg battery cathode materials could be constructed by soft selenide anions, and the electrochemical properties could be manipulated by rational material morphology optimization.

A potential-induced degradation (PID) test method for bifacial double-glass silicon modules is first recommended for studying PID effects at the particular side of interest (the front or rear). This could be achieved by maintaining the same electric potential between solar cells and the untargeted module surface. Using the recommended test method, PID effects on the rear of n-type bifacial passivated emitter rear locally-diffused (bifacial n-PERL) devices (n-base passivated with silicon nitride) are studied. The rear of the n-PERL modules exhibits excellent stability under negative-bias conditions (relative to the ground). However, a huge power loss is observed when they are stressed with + 1000 V, likely due to PID-polarization occurring at the rear. The PID damage is recoverable by illuminating the rear module surface with artificial light. Most of the power loss can even be regenerated by several flashes on the module rear side from a solar simulator.

Transport and homeostasis of transition metals in chloroplasts, which are accurately regulated to ensure supply and to prevent toxicity induced by these metals, are thus crucial for chloroplast function and photosynthetic performance. However, the mechanisms that maintain the balance of transition metals in chloroplasts remain largely unknown. We have characterized an albino-revertible green 1 (arg1) rice mutant. ARG1 encodes an evolutionarily conserved protein belonging to the ATP-binding cassette (ABC) transporter family. Protoplast transfection and immunogold-labelling assays showed that ARG1 is localized in the envelopes and thylakoid membranes of chloroplasts. Measurements of metal contents, metal transport, physiological and transcriptome changes revealed that ARG1 modulates cobalt (Co) and nickel (Ni) transport and homeostasis in chloroplasts to prevent excessive Co and Ni from competing with essential metal cofactors in chlorophyll and metal-binding proteins acting in photosynthesis. Natural allelic variation in ARG1 between indica and temperate japonica subspecies of rice is coupled with their different capabilities for Co transport and Co content within chloroplasts. This variation underpins the different photosynthetic capabilities in these subspecies. Our findings link the function of the ARG1 transporter to photosynthesis, and potentially facilitate breeding of rice cultivars with improved Co homeostasis and consequently improved photosynthetic performance.

Insulinoma, owing to the low incidence and small volume of the tumor, is often undiagnosed. The 72-h fast test is centered on diagnosing insulinoma; however, it cannot be performed on outpatients. Our aim was to evaluate the results of a 3-h oral glucose tolerance test (3-h OGTT) for insulinoma diagnosis.Thirty-seven patients with insulinoma were enrolled for comparison with 42 control subjects. All patients underwent 3-h OGTT with measurements of insulin and C-peptide. The secretion ratios of insulin and C-peptide at 1, 2, and 3 h were calculated by comparison with their values at 0 h. We used logistic regression analysis to establish the predictive models and compared the diagnostic efficiency by receiver operating characteristic analysis.The fasting insulin and C-peptide levels of insulinoma patients were both higher; however, the concentrations at 1 h and 2 h were both lower (P 0.05). The levels at 3 h were not significantly different (P 0.05). Our final logistic regression model was constructed as follows: logit (P) = 8.305 - 0.441 × insulin 2 h/0 h ratio - 1.679 × C-peptide 1 h/0 h ratio. A cutoff value of 0.351 showed the highest diagnostic accuracy, with an area under the curve of 0.97, a sensitivity of 86.5%, and a specificity of 95.2%.The 2-h/0-h insulin ratio, as well as the 1-h/0-h C-peptide ratio, has high diagnostic efficiency for insulinoma. The 2-h OGTT can be an alternative test for diagnosing insulinoma in outpatient settings.

An ambient pressure-induced calcination process was proposed to prepare g-C3N4 with different structures. The porcelain boat with designed porosity is used to control the ambient pressure to change the diffusion behavior of the reaction molecules, thereby controlling the layer structure and rich pyridinic N content of g-C3N4, thus renders superior lithium storage performance.

Solid photocatalysts with high specific surface area, superior photoactivity and ease of recycling are highly desired in chemical process, water treatment and so on. In this study, a facile stepwise sol-gel coating approach was utilized to synthesize Pt decorated oxygen-deficient mesoporous titania microspheres with core-shell structure and convenient magnetic separability (denoted as Fe3O4@SiO2@Pt/mTiO2-x). These photocatalysts consist of magnetic Fe3O4 cores, nonporous insulating SiO2 middle layer and mesoporous anatase TiO2-x shell decorated by Pt nanoparticles (?3.5 nm) through wet impregnation and H2 reduction. As a result of high activity of oxygen-deficiency of black TiO2-x by H2 reduction and efficient inhibition of electron-hole recombination by Pt nanoparticles, the rationally designed core-shell Fe3O4@SiO2@Pt/mTiO2-x photocatalysts exhibit superior photocatalytic performance in rhodamine B (RhB) degradation under visible light irradiation, with more than 98% of RhB degraded within 50 min. These core-shell structured photocatalysts show excellent recyclability under the assistance of magnetic separation with well-retained photocatalytic performance even after running five cycles. This stepwise synthesis method paves the way for the rational design of a high-efficiency recyclable heterogeneous catalyst, including photocatalysts, for various applications. - 2019 This work was supported by the National Natural Science Foundation of China (Nos. 51372041 , 51422202 , 21673048 , 21875044 , 51822202 and 51772050 ), Key Basic Research Program of Science and Technology Commission of Shanghai Municipality (No. 17JC1400100 ), Youth Top-notch Talent Support Program of China, Shanghai Rising-Star Program (No. 18QA1400100 ) and DHU Distinguished Young Professor Program . Scopus

H2S can cause multiple diseases and poses a great threat to human health. However, the precise detection of extremely toxic H2S at room temperature is still a great challenge. Here, a facile solvent evaporation induced aggregating assembly (EIAA) method has been applied for the production of ordered mesoporous carbon (OMCs) in an acidic THF/H2O solution with high-molecular-weight poly(ethylene oxide)-b-polystyrene (PEO-b-PS) copolymers as the structure-directing agent, formaldehyde and resorcinol as carbon precursors. Along with the continuous evaporation of THF from the mixed solution, cylindrical micelles are formed in the solution and further assemble into highly ordered mesostructure. The obtained OMCs possesses a two-dimensional (2D) hexagonal mesostructure with uniform and large pore diameter (∼19.2 nm), high surface area (599 m2/g), and large pore volume (0.92 cm3/g). When being used as the resonant cantilever gas sensor for room-temperature H2S detection, the OMCs has delivered not only a superior gas sensing performance with ultrafast response (14 s) and recovery (21 s) even at low concentration (2 ppm) but also an excellent selectivity toward H2S among various common interfering gases. Moreover, the limit of detection is better than 0.2 ppm, indicating its potential application in environmental monitoring and health protection.

Conductive polymer composites (CPCs) play an important role in various industrial applications including anti-static materials, electromagnetic interference shielding, sensors etc. However, the con...

Mesoporous semiconducting metal oxides (SMOs) heterojunctions are appealing sensors for gas detecting. However, due to the different hydrolysis and condensation mechanism of every metal precursor and the contradiction between high crystallinity and high surface area, the synthesis of mesoporous SMOs heterojunctions with highly ordered mesostructures, highly crystallized frameworks, and high surface area remains a huge challenge. In this work, we develop a novel “acid-base pair” adjusted solvent evaporation induced self-assembly (EISA) strategy to prepare highly crystallized ordered mesoporous TiO2/WO3 (OM-TiO2/WO3) heterojunctions. The WCl6 and titanium isopropoxide (TIPO) are used as the precursors, respectively, which function as the “acid-base pair”, enabling the co-assembly with the structure directing agent (PEO-b-PS) into highly ordered mesostructures. In addition, PEO-b-PS can be converted to rigid carbon which can protect the mesostructures from collapse during the crystallization process. The resultant OM-TiO2/WO3 heterojunctions possess primitive cubic mesostructures, large pore size (∼21.1 nm), highly crystalline frameworks and surface area (∼98 m2/g). As a sensor for acetone, the obtained OM-TiO2/WO3 show excellent response/recovery performance (3 s/5 s), good linear dependence, repeatability, selectivity, and long-term stability (35 days).

Mesoporous metals have attracted extensive attention in electrocatalytic oxidation of methanol owing to their high conductivity, large surface area, and pore volume, which can provide rich and accessible active sites for guest species. In this mini review, we mainly focus on the recent advances of the synthetic strategies of mesoporous metals and their applications in the catalytic oxidation of methanol. The underlying mechanism for both the hard and soft-templating method was first discussed. Then, the influence of morphology, structure, and composition of mesoporous metal and its alloy catalysts on the catalytic activity of methanol oxidation was highlighted. Precious design of the morphology and composition of Pt-group-based alloy electrocatalysts represents an important route to enhance catalytic activity and stability due to the improved tolerance of Pt in intermediate CO in methanol oxidation. Finally, the review is ended with a conclusion and future perspective.

Photo-Fenton processes have been widely studied in wastewater treatment. In this research, the degradation of bisphenol A (BPA) was carried out in a new heterogeneous photo-Fenton process. The ethylenediamine-N,N′-disuccinic acid (EDDS) was used as chelating agent in this system with two different kinds of commercially available nanosized hematite (30 nm and 80 nm) addition. The results showed that the present of EDDS could enhance the degradation efficiency. And can be concluded that the degradation efficiency is better in the system with 30 nm hematite. The TEM, XRD, and specific surface area were conducted to understand the different characteristics of the two size hematite. The adsorption experiments of BPA and EDDS on hematite proved that there was little adsorption of BPA while the EDDS was adsorbed much more on hematite, which has confirmed Fe(III) and EDDS can form Fe(III)-EDDS complex. The effects of different parameters including hematite loading, H2O2, and EDDS concentrations on the degradation process were investigated. According to the results, the optimum condition for BPA degradation using 30 nm (0.8 g L−1 hematite, 0.1 mmol L−1 H2O2, and 1.2 mmol L−1 EDDS) and 80 nm (0.6 g L−1 hematite, 0.05 mmol L−1 H2O2, and 1.2 mmol L−1 EDDS) hematite were selected. It was confirmed that the ·OH plays an important role in the oxidation process through attacking the BPA molecule and produce hydroxyl addition derivative. In addition, O2 can react with electron (e−) and holes (h+) produced by iron oxide under UV irradiation to create 1O2, which could work as potential reactive species to oxidize BPA.

Background and Aims. Recent epidemiological evidence indicates an association between urolithiasis and atherosclerosis; however, results are incongruous. Our aim is to summarize the association between urolithiasis and arteriosclerosis risk through a detailed meta-analysis. Methods. Relevant studies published before April 2019 were identified by searching OVID, EMBASE, PubMed, Web of Science database, and Cochrane Library. The relationship between urolithiasis and the risk of atherosclerosis was assessed by using odds ratio (OR) values and the corresponding 95% confidence intervals (CIs), and the selection of fixed- or random-effects model based on heterogeneity. Results. The meta-analysis includes 8 observational studies that contained 70,716 samples. Pooled results showed that urolithiasis was associated with an increased adjusted and unadjusted risk estimated for atherosclerosis (P=0.017 and P=0.014, respectively), especially in coronary artery and carotid atherosclerosis, which was associated with the outcome of CV disease. Interestingly, when we merged the data from the vast majority of these samples (n = 65,751/70,716) with serum uric acid levels less than 6.0 mg/dl, it still showed that urolithiasis was associated with a higher risk of atherosclerosis (P<0.001) and with no evidence of heterogeneity (I2 = 0.0%, P=0.697). Furthermore, we also found that renal calculi would increase the risk of moderate or severe atherosclerosis (P<0.001) and recurrent renal calculi were associated with the incidence of atherosclerosis (P=0.007). Conclusions. Urolithiasis is associated with an increased risk for atherosclerosis, especially in coronary artery and carotid atherosclerosis. Urolithiasis may be another potential risk factor of atherosclerosis, which is independent of serum uric acid levels.

PURPOSE: To characterize retinal neurovasculature changes after small-incision lenticule extraction (SMILE) in myopic patients. SETTING: Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University, China. DESIGN: Prospective interventional study. METHODS: The corrected distance visual acuity/uncorrected distance visual acuity, corrected intraocular pressure (CIOP), and corneal tomography were evaluated at baseline (PRE), postoperative day (POD) 1, and POD 7. Ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses were measured. The vessel area densities (VADs, %), vessel skeleton densities (VSDs, %), vessel diameter index (VDI), and fractal dimensions (Dbox) of the superficial vascular plexus (SVP) and deep vascular plexus (DVP) were measured in a circular area (ϕ 2.5 mm) centered on the fovea. RESULTS: A total of 38 myopic patients were recruited. The GCIPL thickness was increased after SMILE at POD 1 and POD 7 (P < .01) but no significant changes in the pRNFL thickness. The VAD, VSD, and Dbox of the SVP were decreased at POD 1 (P < .01), but not at POD 7. The VDI in small vessels of the SVP and DVP was decreased at POD 1 (P < .05) and increased at POD 7 (P < .05). Changes in CIOP were positively correlated with changes in the GCIPL thickness. Changes in CIOP were negatively correlated with changes in the VAD of small vessels and the Dbox of total vessels in the DVP. Changes in CIOP were negatively correlated with the VSD and VDI of small vessels in the DVP and changes in the VDI of big vessels in the SVP. CONCLUSIONS: The transient fluctuations in the retinal neurovasculature after SMILE may represent a characteristic homeostasis pattern in patients after refractive surgery.

Solid-state Li metal batteries (SSLMBs) have attracted considerable interests due to their promising energy density as well as high safety. However, the realization of a well-matched Li metal/solid-state electrolyte (SSE) interface remains challenging. Herein, we report g-C3 N4 as a new interface enabler. We discover that introducing g-C3 N4 into Li metal can not only convert the Li metal/garnet-type SSE interface from point contact to intimate contact but also greatly enhance the capability to suppress the dendritic Li formation because of the greatly enhanced viscosity, decreased surface tension of molten Li, and the in situ formation of Li3 N at the interface. Thus, the resulting Li-C3 N4 |SSE|Li-C3 N4 symmetric cell gives a significantly low interfacial resistance of 11 Ω cm2 and a high critical current density (CCD) of 1500 μA cm-2 . In contrast, the same symmetric cell configuration with pristine Li metal electrodes has a much larger interfacial resistance (428 Ω cm2 ) and a much lower CCD (50 μA cm-2 ).

Cu–Zn composite oxide catalysts were prepared by a co-precipitation method and used in the anisole acetylation reaction. Through experimental study and characterization analysis, we have found that the activity of the catalysts derived from the Lewis acidity of the octahedrally coordinated Cu2+ (CuO2+) and ZnO plays an important role in promoting the dispersion of CuO2+ active sites, adjusting the surface structure and coordination of the catalysts. Due to the integration of ZnO and CuO with different degrees of dispersion, some of the tetrahedrally coordinated Cu2+ (CuT2+) species are converted to a low binding energy CuO2+ on different levels. When ZnO is completely dispersed in the CuO crystalline lattice, the amount of CuT2+ is at its lowest and catalyst activity is highest, with the conversion of anisole reaching 92.8% with a selectivity for p-methoxyacetophenone (p-MAP) of 97.0% under solvent-free conditions. More importantly, the catalyst can be reused three times without any treatment.

International audience; In this study, a series of Fe-doped g-C3N4 (Fe–C3N4) samples was synthesized and characterized via X-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflection spectroscopy (UV-vis DRS), and photoluminescence (PL) spectroscopy. The photocatalytic activity of the synthesized Fe–C3N4 was investigated toward methylene blue (MB) degradation with hydrogen peroxide (H2O2) assistance. The results showed that the Fe–C3N4 heterogeneous photo-Fenton-like system showed excellent catalytic performance when the pH value was varied from 3.0 to 9.0. Evaluating the effects of various inorganic anions in the Fe–C3N4 heterogeneous photo-Fenton-like system, HCO3− showed a dual effect on MB degradation, and Cl− and NO3− showed an inhibitory effect on MB degradation. Evaluating the effects of inorganic cations, Al3+, Mg2+, and Ca2+ strongly inhibited MB degradation. Recycling experiments demonstrated that Fe–C3N4 possesses good reusability and stability. Quenching experiments were carried out, and it was found that hydroxyl radicals (·OH) were the primary active species in the system. Besides, nine intermediates were identified via LC/MS, and a possible MB degradation pathway in the system was proposed. This study could promote the application of this Fe–C3N4 heterogeneous photo-Fenton-like system in realistic dye wastewater.

This paper reports the gain-switched InP-based $\boldsymbol{1.55 \mu\mathrm{m}}$ Qdash lasers on silicon. We investigated the laser performance and related physical parameters by carrying out gain-switching test for lasers on Si and InP. The future direction of improving laser performance was pointed by analyzing the parameters.

Compared with low-yield extraction from plants and environmentally unfriendly chemical synthesis, biocatalysis by asparagine synthetase (AS) for preparation of L-asparagine (L-Asn) has become a potential synthetic method. However, low enzyme activity of AS and high cost of ATP in this reaction restricts the large-scale preparation of L-Asn by biocatalysis. In this study, gene mining strategy was used to search for novel AS with high enzyme activity by expressing them in Escherichia coli BL21 (DE3) or Bacillus subtilis WB600. The obtained LsaAS-A was determined for its enzymatic properties and used for subsequent preparation of L-Asn. In order to reduce the use of ATP, a class III polyphosphate kinase 2 from Deinococcus ficus (DfiPPK2-Ⅲ) was cloned and expressed in E. coli BL21 (DE3), Rosetta (DE3) or RosettagamiB (DE3) for ATP regeneration. A coupling reaction system including whole cells expressing LsaAS-A and DfiPPK2-Ⅲ was constructed to prepare L-Asn from L-aspartic acid (L-Asp). Batch catalytic experiments showed that sodium hexametaphosphate (>60 mmol L−1) and L-Asp (>100 mmol L−1) could inhibit the synthesis of L-Asn. Under fed-batch mode, L-Asn yield reached 90.15% with twice feeding of sodium hexametaphosphate. A final concentration of 218.26 mmol L−1 L-Asn with a yield of 64.19% was obtained when L-Asp and sodium hexametaphosphate were fed simultaneously.

Deposition of SiO 2 cladding layer is adopted as an option to promote the high temperature performance of LGS based applications. Besides improving the stability of the electrode, the cladding layer also protects the substrate and provides an indirect bonding possibility. By means of a weak form nonlinear FEM simulation, we get thorough understanding of the influences the SiO 2 layer brings. With a SiO 2 cladding layer, the electromechanical coupling factor (K2) decreases and wave velocity increases. The layer also suppresses spurious mode on (0°, 22°, 31°) cut. Additionally, the temperature-frequency relation of the resonator can be manipulated by varying the thickness of the layer due to the positive temperature coefficiency of frequency (TCF) of SiO 2 . The simulation results provide options and references for a more stable high temperature LGS based application design.

Developing nonmetallic carbon-based electrocatalysts that are affordable and have high activity and stability for carbon dioxide (CO2) reduction to syngas is a new and challenging strategy for solving the energy crisis. Here, we prepared a highly active ultrathin nitrogen (N)-doped carbon nanosheet (UNCN) electrocatalyst. By tuning the applied potential of the UNCN-900 (900 represents the carbonization temperature) electrode, we could tune the H2/CO ratio in clean syngas within a wide range with extra-high Faradic efficiency (FE). The maximum FECO reached 91%, which represented the highest value among the reported nonmetallic carbon-based electrocatalysts for CO2 reduction to syngas. According to the results of experiments and density functional theory calculations, we proved that pyridinic-N in UNCNs-900 is the active site of the CO2 reduction reaction (CO2RR) and that graphitic-N may be the active site for the hydrogen evolution reaction. These results provide a useful case for electrochemical CO2 reduction to syngas with a tunable H2/CO ratio using nonmetallic carbon-based electrocatalysts.

Aeromonas hydrophila can pose a great threat to survival of freshwater fish. In this study, A. hydrophila challenge could promote the erythrocyte hemolysis, increase free hemoglobin (FHB) level and generate malondialdehyde (MDA) production in plasma but decrease the levels of total antioxidant capacity (T-AOC), total superoxide dismutase (SOD), catalase (CAT), alkaline phosphatase (ALP) and lysozyme (LZM) of red crucian carp (RCC, 2 N = 100) and triploid hybrid fish (3 N fish, 3 N = 150) following A. hydrophila challenge. Elevated expression levels of heat shock protein 90 alpha (HSP90α), matrix metalloproteinase 9 (MMP-9), free fatty acid receptor 3 (FFAR3), paraoxonase 2 (PON2) and cytosolic phospholipase A2 (cPLA2) were observed in A. hydrophila-infected fish. In addition, A. hydrophila challenge could significantly increase expressions of cortisol, leucine, isoleucine, glutamate and polyunsaturated fatty acids (PUFAs) in RCC and 3 N, while glycolysis and tricarboxylic acid cycle appeared to be inactive. We identified differential fatty acid derivatives and their metabolic networks as crucial biomarkers from metabolic profiles of different ploidy cyprinid fish subjected to A. hydrophila infection. These results highlighted the comparative metabolic strategy of different ploidy cyprinid fish against bacterial infection.