This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions....This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.It proposes the idea of introducing spray pyrolysis technology into the rare earth extraction and separation processes.This paper briefly describes the development history of chloride spray pyrolysis technology,focusing on the research status and application progress of rare earth chloride solution and magnesium chloride solution spray pyrolysis technology,as well as spray pyrolysis equipment.The paper also analyzes the challenges and technical intricacies associated with applying spray pyrolysis technology to chloride solutions in the rare earth extraction and separation processes.Additionally,it explores future trends and proposes strategies to facilitate the full recycling of acids and bases,streamline the process flow,and enhance the prospects for green and low-carbon rare earth metallurgy.展开更多
This study utilizes data from a 3D lightning location system,polarimetric radar,and current measurements from channels of triggered lightning flashes(TLFs)to analyze the structural characteristics of the parent thunde...This study utilizes data from a 3D lightning location system,polarimetric radar,and current measurements from channels of triggered lightning flashes(TLFs)to analyze the structural characteristics of the parent thunderstorms associated with negative TLFs in South China.The triggered-flash region(TFR)displays distinct stratiform cloud characteristics,including lower radar reflectivity heights and a predominance of ice crystals and dry snow above the 0℃ layer.In contrast,the thunderstorm convection core region(CCR)tends to have more graupel particles in the mixed-phase layers and exhibits an ice-water content peak approximately 3.4 times that of the TFR.The charge regions involved in discharges in TFRs exhibit a dipolar charge structure,with the-5℃ layer roughly dividing the upper positive and lower negative charge regions.Conversely,the CCRs feature a typical tripolar charge structure.The dominant dipole charge structure in the TFR results in an increase in the negative charge field below the negative charge region with height,providing a necessary condition for successfully triggering negative TLFs.Furthermore,the horizontal extent of TLFs is positively correlated with their duration and charge transfer.Regions where TLF channels with larger charge transfers propagate tend to have greater maximum radar reflectivity but lower average radar reflectivity compared to regions with TLFs with smaller charge transfer.展开更多
CuBi_(2)O_(4)is identified as a promising photocathode in photoelectrochemical(PEC)water splitting systems.However,the PEC performance of CuBi_(2)O_(4)is far from expected due to the limited separation and transport e...CuBi_(2)O_(4)is identified as a promising photocathode in photoelectrochemical(PEC)water splitting systems.However,the PEC performance of CuBi_(2)O_(4)is far from expected due to the limited separation and transport efficiency of photogenerated carriers.To address the above issues,a cost-effective ternary Cu:NiO_(X)/CuBi_(2)O_(4)/CuO composite photocathode was designed.Firstly,a thin Cu:NiO_(X)film was inserted between CuBi_(2)O_(4)and FTO conducting substrate as a hole-selective layer,which promotes the transmission of photogenerated holes to the FTO substrate effectively.Furthermore,the modification of CuO film on the CuBi_(2)O_(4)electrode not only increases the absorption of sunlight and generates more photogenerated carriers,but also constitutes a heterojunction with CuBi_(2)O_(4),creating a built-in electric field,which facilitates the separation of electrons and holes,and accelerates the electrons transfer to electrode–electrolyte interface.The fabricated Cu:NiO_(X)/CuBi_(2)O_(4)/CuO composite photocathode exhibits a surprisingly high photocurrent density of−1.51 mA·cm^(−2)at 0.4 V versus RHE,which is 2.6 times that of the pristine CuBi_(2)O_(4)photocathode.The improved PEC performance is attributed to the synergy effect of the Cu:NiO_(X)hole-selective layer and the CuBi_(2)O_(4)/CuO heterojunction.Moreover,the combination with the BiVO_(4)/CoS,an unbiased overall water splitting was achieved,which has a photocurrent of 0.193 mA·cm^(−2).展开更多
Regard to the real-time dynamic digital twin modelling problem of a new-type distribution network that includes distributed resources such as distributed photovoltaic,energy storage,charging pile,and electric vehicle,...Regard to the real-time dynamic digital twin modelling problem of a new-type distribution network that includes distributed resources such as distributed photovoltaic,energy storage,charging pile,and electric vehicle,a new-type distribution network digital twin topology modeling method based on Common Information Model(CIM)specifications and spectral clustering is proposed.Firstly,according to the specifications of the CIM standard,the digital twin topology models of distributed resources are extended and established.Secondly,based on the digital twin topology models of distributed resources,a digital twin aggregation modelling method for new-type distribution network is proposed based on spectral clustering.Furthermore,an online linked update strategy for the digital twin model of new-type distribution network that integrates real-time topology states is proposed.Finally,a case study is conducted on a distribution network in a certain demonstration area in China,and the results verify the practicability and effectiveness of the method proposed in this paper.This lays the foundation for the application of electrical network twin analysis,such as power flow calculation,optimal power flow,economic dispatch,and safety check,in a new-type distribution network that includes diversified distributed resources.展开更多
Interfacial defects and environmental instability at perovskite surfaces pose significant challenges for inverted perovskite solar cells(PSCs). Surface post-treatment strategies have emerged as a viable approach to im...Interfacial defects and environmental instability at perovskite surfaces pose significant challenges for inverted perovskite solar cells(PSCs). Surface post-treatment strategies have emerged as a viable approach to improve film quality and passivate defects. Although organic molecules can passivate both surfaces and grain boundaries via hydrogen or covalent bonding,their limited adsorption specificity often results in incomplete defect neutralization. In this work, we introduce a bilayer passivation approach employing phenethylammonium iodide(PEAI) and n-octylammonium iodide(OAI) to concurrently mitigate nonradiative recombination and improve stability. PEAI passivates undercoordinated Pb^(2+) at grain boundaries and surfaces, effectively eliminating deep-level traps and suppressing non-radiative losses. Meanwhile, OAI forms a hydrophobic barrier on the perovskite surface through its long alkyl chains, inhibiting moisture penetration without compromising interfacial charge transport. As a result, the perovskite film exhibits significantly enhanced optoelectronic performance and environmental stability,achieving a champion power conversion efficiency(PCE) of 24.48%.展开更多
Buyang Huanwu decoction （BYHWD）, a traditional Chinese herbal prescription, has been widely used clinically to treat stroke in China for hundreds of years; however, the mechanisms of this drug for stroke treatment a...Buyang Huanwu decoction （BYHWD）, a traditional Chinese herbal prescription, has been widely used clinically to treat stroke in China for hundreds of years; however, the mechanisms of this drug for stroke treatment are still unclear. This study aims to observe the cerebral angiogenesis effects of BYHWD on chronic brain injury after focal cerebral ischemia in rats and to explore its possible mechanisms. The ischemia was induced by occlusion of the right middle cerebral artery for 90 min. BYHWD （12.5 and 25.0 g/（kg.d）, equivalent to the dry weight of the raw materials） was orally administered twice a day beginning 2 h after surgery. BYHWD significantly attenuated the neurological dysfunction, infarct volume, and brain atrophy after ischemia. There was a significant increase in the microvessel density, as assessed by immunofluorescence CD31, and a significant increase in angiopoietin-1 （Ang-1） in the pe- numbra areas of the rats was shown by immunohistochemical staining and Western blotting. The results indicate that the neurorestorative effects of BYHWD are associated with angiogenesis and the enhancement of the expressions of Ang-1 on chronic brain injury after focal cerebral ischemia.展开更多
Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 al...Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 also has potential for capturing multiple flue gas components, including NOx, SOxand CO_2, and producing value-added chemicals. However, its high volatility and low reactivity towards CO_2 limit its economic viability. Considerable efforts have been made to advance aqueous NH3-based post-combustion capture technologies in the last few years: in particular, General Electric's chilled NH3 process, CSIRO's mild-temperature aqueous NH3 process and SRI International's mixed-salts(NH3 and potassium carbonate) technology. Here, we review these research activities and other developments in the field, and outline future research needed to further improve aqueous NH3-based CO_2 capture technologies.展开更多
The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low...The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.展开更多
Highly virulent porcine epidemic diarrhea virus(PEDV)strains re-emerged and circulated in China at the end of 2010,causing significant economic losses in the pork industry worldwide.To understand the genetic dynamics ...Highly virulent porcine epidemic diarrhea virus(PEDV)strains re-emerged and circulated in China at the end of 2010,causing significant economic losses in the pork industry worldwide.To understand the genetic dynamics of PEDV during its passage in vitro,the PEDV G2 strain FJzzl was serially propagated in Vero cells for up to 200 passages.The susceptibility and adaptability of the FJzzl strain increased gradually as it was serially passaged in vitro.Sequence analysis revealed that amino acid(aa)changes were mainly concentrated in the S glycoprotein,which accounted for 72.22%-85.71%of all aa changes.A continuous aa deletion(^(55)I^(56)G^(57)E→^(55)K^(56)Δ^(57)Δ)occurred in the N-terminal domain of S1(Sl-NTD).To examine how the aa changes affected its virulence,FJzzl-F20 and FJzzl-F200 were selected to simultaneously evaluate their pathogenicity in suckling piglets.All the piglets in the FJzzl-F20-infected group showed typical diarrhea at 24 h postinfection,and the piglets died successively by 48 h postinfection.However,the clinical signs of the piglets in the FJzzl-F200-infected group were significantly weaker,and no deaths occurred.The FJzzl-F200-infected group also showed a lower level of fecal viral shedding and lower viral loads in the intestinal tissues,and no obvious histopathological lesions.TypeⅠandⅢinterferon were induced in the FJzzl-F200 infection group,together with pro-inflammatory cytokines,such as TNF-α,IL-1βand IL-8.These results indicate that the identified genetic changes may contribute to the attenuation of FJzzl strain,and the attenuated FJzzl-F200 may have the potential for developing PEDV live-attenuated vaccines.展开更多
Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical ...Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiency<10%)and high-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline media.Due to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic performance.In conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction reaction.Overall,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR performance.The significance of this work is to provide a promising candidate in the future synthesis of ammonia.展开更多
Currently, various porcine reproductive and respiratory syndrome virus(PRRSV) variants emerged worldwide with different genetic characteristics and pathogenicity, increasing the difficulty of PRRS control. In this stu...Currently, various porcine reproductive and respiratory syndrome virus(PRRSV) variants emerged worldwide with different genetic characteristics and pathogenicity, increasing the difficulty of PRRS control. In this study, a PRRSV strain named HBap4-2018 was isolated from swine herds suffering severe respiratory disease with high morbidity in Hebei Province of China in 2018. The genome of HBap4-2018 is 15,003 nucleotides in length, and compared with NADC30-like PRRSV, nsp2 of HBap4-2018 has an additional continuous deletion of five amino acids. Phylogenetic analysis based on complete genome and ORF5 showed that HBap4-2018 belonged to lineage 8 of PRRSV-2, which was characterized by highly variable genome. However, HBap4-2018 was classified into lineage 1 based on phylogenetic analysis of nsp2,sharing higher amino acid homology(85.3%–85.5%) with NADC30-like PRRSV. Further analysis suggested that HBap4-2018 was a novel natural recombinant PRRSV with three recombinant fragments in the genome, of which highly pathogenic PRRSV(HP-PRRSV) served as the major parental strains, while NADC30-like PRRSV served as the minor parental strains. Five recombination break points were identified in nsp2, nsp3, nsp5, nsp9 and ORF6, respectively,presenting a novel recombinant pattern in the genome. Piglets inoculated with HBap4-2018 presented typical clinical signs with a mortality rate of 60%. High levels of viremia and obvious macroscopic and histopathological lesions in the lungs were observed, revealing the high pathogenicity of HBap4-2018 in piglets.展开更多
基金supported by the National Key Research and Development Program of China(2022YFB3504501)the National Natural Science Foundation of China(52274355)。
文摘This paper focuses on the preparation of rare earth oxide products from rare earth chloride solutions during the rare earth extraction and separation processes,as well as the recycling of magnesium chloride solutions.It proposes the idea of introducing spray pyrolysis technology into the rare earth extraction and separation processes.This paper briefly describes the development history of chloride spray pyrolysis technology,focusing on the research status and application progress of rare earth chloride solution and magnesium chloride solution spray pyrolysis technology,as well as spray pyrolysis equipment.The paper also analyzes the challenges and technical intricacies associated with applying spray pyrolysis technology to chloride solutions in the rare earth extraction and separation processes.Additionally,it explores future trends and proposes strategies to facilitate the full recycling of acids and bases,streamline the process flow,and enhance the prospects for green and low-carbon rare earth metallurgy.
基金funded by the Natural Science Foundation of China(Grant No.U2342215)Key Laboratory of South China Sea Meteorological Disaster Prevention and Mitigation of Hainan Province(Grant No.SCSF202302)。
文摘This study utilizes data from a 3D lightning location system,polarimetric radar,and current measurements from channels of triggered lightning flashes(TLFs)to analyze the structural characteristics of the parent thunderstorms associated with negative TLFs in South China.The triggered-flash region(TFR)displays distinct stratiform cloud characteristics,including lower radar reflectivity heights and a predominance of ice crystals and dry snow above the 0℃ layer.In contrast,the thunderstorm convection core region(CCR)tends to have more graupel particles in the mixed-phase layers and exhibits an ice-water content peak approximately 3.4 times that of the TFR.The charge regions involved in discharges in TFRs exhibit a dipolar charge structure,with the-5℃ layer roughly dividing the upper positive and lower negative charge regions.Conversely,the CCRs feature a typical tripolar charge structure.The dominant dipole charge structure in the TFR results in an increase in the negative charge field below the negative charge region with height,providing a necessary condition for successfully triggering negative TLFs.Furthermore,the horizontal extent of TLFs is positively correlated with their duration and charge transfer.Regions where TLF channels with larger charge transfers propagate tend to have greater maximum radar reflectivity but lower average radar reflectivity compared to regions with TLFs with smaller charge transfer.
基金supported by the National Natural Science Foundation of China(No.61804039)the University Natural Sciences Research Project of Anhui Province(No.2022AH010096)+1 种基金the Talent Research Fund of Hefei University(No.20RC35)the Natural Science Foundation of Anhui Higher Education Institution of China(No.2023AH040160).
文摘CuBi_(2)O_(4)is identified as a promising photocathode in photoelectrochemical(PEC)water splitting systems.However,the PEC performance of CuBi_(2)O_(4)is far from expected due to the limited separation and transport efficiency of photogenerated carriers.To address the above issues,a cost-effective ternary Cu:NiO_(X)/CuBi_(2)O_(4)/CuO composite photocathode was designed.Firstly,a thin Cu:NiO_(X)film was inserted between CuBi_(2)O_(4)and FTO conducting substrate as a hole-selective layer,which promotes the transmission of photogenerated holes to the FTO substrate effectively.Furthermore,the modification of CuO film on the CuBi_(2)O_(4)electrode not only increases the absorption of sunlight and generates more photogenerated carriers,but also constitutes a heterojunction with CuBi_(2)O_(4),creating a built-in electric field,which facilitates the separation of electrons and holes,and accelerates the electrons transfer to electrode–electrolyte interface.The fabricated Cu:NiO_(X)/CuBi_(2)O_(4)/CuO composite photocathode exhibits a surprisingly high photocurrent density of−1.51 mA·cm^(−2)at 0.4 V versus RHE,which is 2.6 times that of the pristine CuBi_(2)O_(4)photocathode.The improved PEC performance is attributed to the synergy effect of the Cu:NiO_(X)hole-selective layer and the CuBi_(2)O_(4)/CuO heterojunction.Moreover,the combination with the BiVO_(4)/CoS,an unbiased overall water splitting was achieved,which has a photocurrent of 0.193 mA·cm^(−2).
基金Supported by Science and Technology Project of State Grid Corporation of China(5108-202218280A-2-396-XG).
文摘Regard to the real-time dynamic digital twin modelling problem of a new-type distribution network that includes distributed resources such as distributed photovoltaic,energy storage,charging pile,and electric vehicle,a new-type distribution network digital twin topology modeling method based on Common Information Model(CIM)specifications and spectral clustering is proposed.Firstly,according to the specifications of the CIM standard,the digital twin topology models of distributed resources are extended and established.Secondly,based on the digital twin topology models of distributed resources,a digital twin aggregation modelling method for new-type distribution network is proposed based on spectral clustering.Furthermore,an online linked update strategy for the digital twin model of new-type distribution network that integrates real-time topology states is proposed.Finally,a case study is conducted on a distribution network in a certain demonstration area in China,and the results verify the practicability and effectiveness of the method proposed in this paper.This lays the foundation for the application of electrical network twin analysis,such as power flow calculation,optimal power flow,economic dispatch,and safety check,in a new-type distribution network that includes diversified distributed resources.
基金financial support from the National Key R&D Program of China (No. 2021YFB3800102)the Key Research Project of Hefei Normal University (No. 2023QN08)+2 种基金National Natural Science Foundation of China (Nos. U22A20142, 52302324, and 52272252)CASHIPS Director's Fund (Nos. YZJJ-GGZX-2022-01 and YZJJ202304-CX)Dreams Foundation of Jianghuai Advance Technology Center (No. 2023-ZM01X011)。
文摘Interfacial defects and environmental instability at perovskite surfaces pose significant challenges for inverted perovskite solar cells(PSCs). Surface post-treatment strategies have emerged as a viable approach to improve film quality and passivate defects. Although organic molecules can passivate both surfaces and grain boundaries via hydrogen or covalent bonding,their limited adsorption specificity often results in incomplete defect neutralization. In this work, we introduce a bilayer passivation approach employing phenethylammonium iodide(PEAI) and n-octylammonium iodide(OAI) to concurrently mitigate nonradiative recombination and improve stability. PEAI passivates undercoordinated Pb^(2+) at grain boundaries and surfaces, effectively eliminating deep-level traps and suppressing non-radiative losses. Meanwhile, OAI forms a hydrophobic barrier on the perovskite surface through its long alkyl chains, inhibiting moisture penetration without compromising interfacial charge transport. As a result, the perovskite film exhibits significantly enhanced optoelectronic performance and environmental stability,achieving a champion power conversion efficiency(PCE) of 24.48%.
基金Projcct sup portcd bythc Plan of Zhejiang Scientific Rcscarch in Traditional Chincsc Medicinc （No. 2010ZZ007）, China
文摘Buyang Huanwu decoction （BYHWD）, a traditional Chinese herbal prescription, has been widely used clinically to treat stroke in China for hundreds of years; however, the mechanisms of this drug for stroke treatment are still unclear. This study aims to observe the cerebral angiogenesis effects of BYHWD on chronic brain injury after focal cerebral ischemia in rats and to explore its possible mechanisms. The ischemia was induced by occlusion of the right middle cerebral artery for 90 min. BYHWD （12.5 and 25.0 g/（kg.d）, equivalent to the dry weight of the raw materials） was orally administered twice a day beginning 2 h after surgery. BYHWD significantly attenuated the neurological dysfunction, infarct volume, and brain atrophy after ischemia. There was a significant increase in the microvessel density, as assessed by immunofluorescence CD31, and a significant increase in angiopoietin-1 （Ang-1） in the pe- numbra areas of the rats was shown by immunohistochemical staining and Western blotting. The results indicate that the neurorestorative effects of BYHWD are associated with angiogenesis and the enhancement of the expressions of Ang-1 on chronic brain injury after focal cerebral ischemia.
文摘Aqueous ammonia(NH3) is a promising alternative solvent for the capture of industrial CO_2 emissions, given its high chemical stability and CO_2 removal capacity, and low material costs and regeneration energy. NH3 also has potential for capturing multiple flue gas components, including NOx, SOxand CO_2, and producing value-added chemicals. However, its high volatility and low reactivity towards CO_2 limit its economic viability. Considerable efforts have been made to advance aqueous NH3-based post-combustion capture technologies in the last few years: in particular, General Electric's chilled NH3 process, CSIRO's mild-temperature aqueous NH3 process and SRI International's mixed-salts(NH3 and potassium carbonate) technology. Here, we review these research activities and other developments in the field, and outline future research needed to further improve aqueous NH3-based CO_2 capture technologies.
基金Supported by Ministry of Industry and Information(No.K24097)
文摘The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics(CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.
基金supported by the National Program on Key Research Project of China(2016YFD0500100)the Shanghai Youth Scientific and Technological Yang Fan Program Grant(20YF1457800)+3 种基金the National Natural Science Foundation of China(31472207)the earmarked fund for Modern Agro-industry Technology Research System of China(CARS-36)the China Postdoctoral Science Foundation(2020M670555)Shanghai Minhang District talent development special funds。
文摘Highly virulent porcine epidemic diarrhea virus(PEDV)strains re-emerged and circulated in China at the end of 2010,causing significant economic losses in the pork industry worldwide.To understand the genetic dynamics of PEDV during its passage in vitro,the PEDV G2 strain FJzzl was serially propagated in Vero cells for up to 200 passages.The susceptibility and adaptability of the FJzzl strain increased gradually as it was serially passaged in vitro.Sequence analysis revealed that amino acid(aa)changes were mainly concentrated in the S glycoprotein,which accounted for 72.22%-85.71%of all aa changes.A continuous aa deletion(^(55)I^(56)G^(57)E→^(55)K^(56)Δ^(57)Δ)occurred in the N-terminal domain of S1(Sl-NTD).To examine how the aa changes affected its virulence,FJzzl-F20 and FJzzl-F200 were selected to simultaneously evaluate their pathogenicity in suckling piglets.All the piglets in the FJzzl-F20-infected group showed typical diarrhea at 24 h postinfection,and the piglets died successively by 48 h postinfection.However,the clinical signs of the piglets in the FJzzl-F200-infected group were significantly weaker,and no deaths occurred.The FJzzl-F200-infected group also showed a lower level of fecal viral shedding and lower viral loads in the intestinal tissues,and no obvious histopathological lesions.TypeⅠandⅢinterferon were induced in the FJzzl-F200 infection group,together with pro-inflammatory cytokines,such as TNF-α,IL-1βand IL-8.These results indicate that the identified genetic changes may contribute to the attenuation of FJzzl strain,and the attenuated FJzzl-F200 may have the potential for developing PEDV live-attenuated vaccines.
文摘Achieving more meaningful N2 conversion by reducing the energy input and carbon footprint is now being investigated through a method of N2 fixation instead of the Haber-Bosch process.Unfortunately,the electrochemical N2 reduction reaction(NRR)method as a rising approach currently still shows low selectivity(Faradaic efficiency<10%)and high-energy consumption[applied potential at least-0.2 V versus the reversible hydrogen electrode(RHE)].Here,the role of molybdenum aluminum boride single crystals,belonging to a family of ternary transition metal aluminum borides known as MAB phases,is reported for the electrochemical NRR for the first time,at a low applied potential(-0.05 V versus RHE)under ambient conditions and in alkaline media.Due to the unique nano-laminated crystal structure of the MAB phase,these inexpensive materials have been found to exhibit excellent electrocatalytic performances(NH3 yield:9.2μg h^-1cm^-2mgcat^-1.,Faradaic efficiency:30.1%)at the low overpotential,and to display a high chemical stability and sustained catalytic performance.In conjunction,further mechanism studies indicate B and Al as main-group metals show a highly selective affinity to N2 due to the strong interaction between the B 2p/Al 3p band and the N 2p orbitals,while Mo exhibits specific catalytic activity toward the subsequent reduction reaction.Overall,the MAB-phase catalyst under the synergy of the elements within ternary compound can suppress the hydrogen evolution reaction and achieve enhanced NRR performance.The significance of this work is to provide a promising candidate in the future synthesis of ammonia.
基金The siudy was supported by the Shanghai Municipal Agriculture Science and Technology Project(2020-02-0800-08-F01465)the National Natural Science Foundation of China(32072861)+1 种基金the Natural Science Foundation of Shanghai(20ZR1469600)the earmarked fund for Modern Agro-industry Technology Research System of China(CARS-35)。
文摘Currently, various porcine reproductive and respiratory syndrome virus(PRRSV) variants emerged worldwide with different genetic characteristics and pathogenicity, increasing the difficulty of PRRS control. In this study, a PRRSV strain named HBap4-2018 was isolated from swine herds suffering severe respiratory disease with high morbidity in Hebei Province of China in 2018. The genome of HBap4-2018 is 15,003 nucleotides in length, and compared with NADC30-like PRRSV, nsp2 of HBap4-2018 has an additional continuous deletion of five amino acids. Phylogenetic analysis based on complete genome and ORF5 showed that HBap4-2018 belonged to lineage 8 of PRRSV-2, which was characterized by highly variable genome. However, HBap4-2018 was classified into lineage 1 based on phylogenetic analysis of nsp2,sharing higher amino acid homology(85.3%–85.5%) with NADC30-like PRRSV. Further analysis suggested that HBap4-2018 was a novel natural recombinant PRRSV with three recombinant fragments in the genome, of which highly pathogenic PRRSV(HP-PRRSV) served as the major parental strains, while NADC30-like PRRSV served as the minor parental strains. Five recombination break points were identified in nsp2, nsp3, nsp5, nsp9 and ORF6, respectively,presenting a novel recombinant pattern in the genome. Piglets inoculated with HBap4-2018 presented typical clinical signs with a mortality rate of 60%. High levels of viremia and obvious macroscopic and histopathological lesions in the lungs were observed, revealing the high pathogenicity of HBap4-2018 in piglets.
