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Carbon doped honeycomb-like graphitic carbon nitride (g-C 3 N 4) was prepared by one-step thermal polymerization, which derived from chitosan as a carbon source together with the melamine-cyanuric acid complex as a supramolecular precursor. Interestingly, the carbon doped g-C 3 N 4 displayed an increased specific surface area and a more negative conduction band energy level, which not only provided a large number of reaction sites for the photocatalytic hydrogen production, but also effectively enhances the separation of photogenerated electrons-holes. And the experimental results showed that the hydrogen evolution rate of the optimal sample was as high as 320 μmol·h−1, which is 29.10 times than that of bulk g-C 3 N 4 (11 μmol·h−1). More importantly, this work may provide a promising idea for the design of efficient g-C 3 N 4 by controlling the material morphology and combining the electronic modulation strategy. [ABSTRACT FROM AUTHOR]

[Display omitted] The oxygen evolution reaction (OER) has garnered considerable attention because of its promising prospects in electrochemical energy conversion applications, but a significant challenge is faced by the insufficient understanding of sluggish OER kinetics. In fact, the intrinsic "acceptance-donation" process of electrons between active sites and reactants is responsible for improving OER activity. Herein, we suggest a multielement hybridization strategy to rematch spin electron occupation and energy splitting in high-entropy perovskites with multiple orbital coordination. In this concept, electronic hopping between t 2g and e g orbitals among particular catalytic sites can be obviously enforced due to introducing more favorable energy levels from neighboring metal sites, which can demonstrate multistage orbital hybridization reaction activity. As a result, our proposed multistage-hybridized high-entropy perovskites display an impressive activity of 199.8 mA cm−2 as an overpotential of ∼0.46 V, which is ∼5.3 times that of pristine perovskite. Different from traditional catalyst designs, this study focuses on multistage orbital hybridization and electron exchange interactions through a multisite coordination mechanism to construct a fast reaction pathway. Our findings provide a new strategy for accelerating OER catalytic kinetics. [ABSTRACT FROM AUTHOR]

A pretreatment process for wheat straw using potassium hydroxide (KOH) and recycled black liquor as a treatment reagent was developed and the minimum fresh chemical and water requirement were determined. Black liquor recycling in the pretreatment process resulted in a 75% reduction in fresh water use and 25% in KOH use, when compared to no recycling. It was found that after five batches of treatment, the concentrations of reducing sugar, chemical oxygen demand (COD), and K + in black liquor, reached stable levels. During the pretreatment with black liquor recycling, 32–35% lignin was reduced in wheat straw. The pretreated straw showed reducing sugar yield of 336–366 mg g −1 [total solid (TS)] and methane yield of 290–303 mg g −1 [volatile solid (VS)] when subjected to enzymatic hydrolysis and anaerobic digestion, respectively. [ABSTRACT FROM AUTHOR]

Abstract To improve the methane production of wheat straw (WS), the mono-pretreatment (MP) and co-pretreatment (CP) of WS with KOH and Ca(OH) 2 were conducted in this study. The results showed that the MP with KOH presented better effects than the MP with Ca(OH) 2. However, the CP with 2% KOH combined with 1% Ca(OH) 2 displayed similar effects to those of the MP with 3% KOH, obtaining the cumulative methane yield of 239.8 mL g VS −1 and an improved biodegradability from 56.37% of raw WS to 66.10%. Methane production and kinetic analyses suggested that 2% KOH combined with 1% Ca(OH) 2 was the ideal condition of alkaline pretreatment for anaerobic digestion of WS. The mechanism for the improvement in methane production was clearly described by biochemical component, scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy analyses. Moreover, preliminary economics and energy potential analyses also confirmed that alkaline co-pretreatment was a reasonable method, which not only gave important guidance for future utilization of WS waste but also showed useful reference for the efficient pretreatment of other lignocellulosic wastes. Graphical abstract Image 1 Highlights • 2% KOH combined with 1% Ca(OH) 2 could replace 3% KOH to pretreat WS before AD. • The highest CMY and B D of WS were 239.8 mL g VS −1 and 66.10%, respectively. • Alkaline co-pretreatment was more economically reasonable than mono-pretreatment. • Energy potential for AD of WS after co-pretreatment was 5.09 × 1012 MJ/year. [ABSTRACT FROM AUTHOR]

Efficient and harmless disposal of landfill leachate has attracted increasing attention. In this study, the bio-electro-Fenton method was investigated and developed to degrade the organic compounds in landfill leachate by hydroxyl radical oxidation. The optimal operational parameters (i.e., pH and external voltage) of the bio-electro-Fenton system were detected. Under the conditions of pH 2, 0.6 V, the highest total chemical oxygen demand (COD) decrement efficiency was obtained (about 70%), with apparent removal constant at 6 h (k app-6h) of about 0.12 h−1. Subsequently, to further increase the degradation efficiency, functionalized carbon black and functionalized carbon nanotube (FCNT) were prepared as catalysts for the cathode electrode modification. With 0.4 mg/cm2 FCNT coated on the cathode electrode, 91.3% of the organic compounds were degraded, remaining only 84 mg/L COD (k app-6h = 0.24 h−1). In all the reactors, the COD was mainly decreased in 0–6 h, contributing to over 68% of the total degradation efficiency. In the bio-electro-Fenton system, the bio-anode electrode could enhance H 2 O 2 production and the conversion between Fe2+ and Fe3+ by strengthening electrons generation and transportation via the oxidation of organics by biofilms (dominant with Geobacter) covered on the carbon brush. [Display omitted] • Refractory organics in leachate could be degraded by bio-electro-Fenton process. • 70% COD in leachate was degraded under pH 2 and 0.6 V conditions in MEC system. • 91.3% COD in leachate was degraded when cathode electrode was modified by FCNT. • COD was mainly degraded in 0–6 h, contributing to over 68% of the total efficiency. • Biofilm (mainly Geobacter) could enhance electrons generation and transportation. [ABSTRACT FROM AUTHOR]

Abstract: During investigations into an outbreak of egg production decline, retarded growth, and even death among ducks in Southeast China, a novel Tembusu virus strain named Tembusu virus Fengxian 2010 (FX2010) was isolated. This virus replicated in embryonated chicken eggs and caused embryo death. In cross-neutralization tests, antiserum to the partial E protein of Tembusu virus Mm1775 strain neutralized FX2010, whereas antiserum to Japanese encephalitis virus did not. FX2010 is an enveloped RNA virus of approximately 45–50nm in diameter. Sequence analysis of its E and NS5 genes showed that both genes share up to 99.6% nucleotide sequence identity with Baiyangdian virus, and up to 88% nucleotide sequence identity with their counterparts in Tembusu virus. FX2010 was transmitted without mosquito, and caused systemic infection and lesions in experimentally infected ducks. These results indicate that FX2010 and BYD virus are newly emerged Tembusu virus strains that cause an infectious disease in ducks. [Copyright &y& Elsevier]

Canine bufavirus (CBuV) was first discovered in puppies in Italy in 2016, and subsequent studies have reported its possible relationship with acute enteritis. Currently, there is no specific and quantitative detection method for CBuV. This study examined the conserved NS1 gene and used a pair of specific primers to establish a direct SYBR Green I-based real-time quantitative polymerase chain reaction (qPCR) method for the detection and quantification of CBuV. In the sensitivity experiment, the detection limit of SYBR Green I-based real-time qPCR was 4.676 × 101 copies/μL and that of conventional PCR (cPCR) was 4.676 × 103 copies/μL. Furthermore, the qPCR method did not detect other viruses in dogs, indicating good specificity. The intra-assay coefficient of variation was 0.07–0.55% and the inter-assay coefficient of variation was 0.03–0.11%, indicating good repeatability. In clinical sample testing, the detection rate of qPCR was 5.0% (6/120), higher than that of cPCR (2.5%, 3/120). In addition, the samples that tested CBuV-positive in this experiment were all from dogs with acute enteritis. In summary, the SYBR Green I-based qPCR method established in this study has good sensitivity, specificity, and reproducibility for clinical sample detection and can also assist in future research on CBuV. • The study established a SYBR Green I-based real-time RT-PCR assay for Canine Bufavirus detection. • The assay is highly sensitive, specific, and reproducible. • It provides a tool for clinical diagnostics of Canine Bufavirus infection. [ABSTRACT FROM AUTHOR]

The similar clinical characteristics of canine circovirus (CaCV) and canine astrovirus (CaAstV) infections and high frequency of co-infection make diagnosis difficult. In this study, a duplex SYBR Green I-based real-time polymerase chain reaction (PCR) assay was established for the rapid, simultaneous detection of CaCV and CaAstV. Two pairs of specific primers were designed based on the Rep gene of CaCV and the Cap gene of CaAstV. By using the real-time PCR assay method, the two viruses can be distinguished by the difference in melting temperatures, 79 °C and 86 °C for CaCV and CaAstV, respectively. This assay had high specificity, showing no cross-reaction with other common canine viruses, as well as high sensitivity, with minimum detection limits of 9.25 × 101 copies/μL and 6.15 × 101 copies/μL for CaCV and CaAstV, respectively. Based on the mean coefficient of variation, the method had good reproducibility and reliability. In a clinical test of 57 fecal samples, the rates of positive detection by real-time PCR were 14.04% (8/57) and 12.28% (7/57) for CaCV and CaAstV, respectively, and the rate of co-infection was 8.77% (5/57). In conclusion, the newly established duplex SYBR Green I-based real-time PCR assay is sensitive, specific, reliable, and rapid and is an effective tool for the detection of co-infections with CaCV and CaAstV. • A duplex SYBR Green I based real-time PCR assay was established for CaCV and CaAstV. • Specific primers targeting Rep of CaCV and Cap of CaAstV were designed. • The assay had high specificity, sensitivity, and reproducibility. [ABSTRACT FROM AUTHOR]