Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery fa...Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery failure under various preload forces.The time-sequence relationship among expansion force,voltage,and temperature during thermal abuse under five categorised stages is revealed.Three characteristic peaks are identified for the expansion force,which correspond to venting,internal short-circuiting,and thermal runaway.In particular,an abnormal expansion force signal can be detected at temperatures as low as 42.4°C,followed by battery thermal runaway in approximately 6.5 min.Moreover,reducing the preload force can improve the effectiveness of the early-warning method via the expansion force.Specifically,reducing the preload force from 6000 to 1000 N prolongs the warning time(i.e.,227 to 398 s)before thermal runaway is triggered.Based on the results,a notable expansion force early-warning method is proposed that can successfully enable early safety warning approximately 375 s ahead of battery thermal runaway and effectively prevent failure propagation with module validation.This study provides a practical reference for the development of timely and accurate early-warning strategies as well as guidance for the design of safer battery systems.展开更多
氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能...氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能源制氢的可持续手段.但其阳极氧析出反应(OER)为四电子/质子转移过程,反应动力学缓慢,同时强氧化性和强酸性环境会对阳极催化剂的产生腐蚀,导致稳定性差,因此亟需开发高效且稳定的催化剂.研究发现,无定型氧化铱材料中的特殊缺陷结构可显著提升其催化酸性OER的活性,但该结构也会加速反应过程中铱的溶解,导致催化剂稳定性降低,严重限制了其实际应用.本文采用高价金属掺杂的策略,利用高价金属元素与氧的强成键作用,对无定型氧化铱的整体结构及活性位点起到优化且稳定的作用.首先,采用改性的亚当斯熔融法制备了金属钽掺杂的无定型氧化铱:350-Ta@IrO_(x),400-Ta@IrO_(x),450-Ta@IrO_(x)(350,400和450代表样品分别在350,400和450℃烧结),并用于催化酸性OER;作为对比,制备了无掺杂的无定型氧化铱:350-IrO_(x),400-IrO_(x)和450-IrO_(x).然后,通过扫描电子显微镜、透射电子显微镜(TEM)和X射线衍射等表征技术考察了材料的宏观形貌及微观结构.结果表明,掺杂后的350-Ta@IrO_(x)材料表面具有丰富的氧空位贡献的活性位点,且表现出多晶的超小纳米颗粒形貌.电化学测试结果表明,350-Ta@IrO_(x)具有较好的酸性OER活性,在10 mA cm-2的电流密度下,过电势仅为223 mV,在1.55 V vs.RHE的电位下质量活性为1207.4 A gIr-1,是商业二氧化铱的147.7倍.且该催化剂的稳定性比未掺杂Ta样品及商业二氧化铱有明显提升,在0.5 mol L^(-1)硫酸溶液中反应500 h后电位未发生明显变化.密度泛函理论计算结果表明,Ta掺杂与构建缺陷有利于OER决速步中水分子的亲核进攻,从而提升催化活性并降低反应过电势.为进一步研究材料在酸性OER工作状态下具有较好稳定性的原因,采用TEM和X射线光电子能谱等对反应前后的材料进行表征.结果表明,350-Ta@IrO_(x)在反应前后结构保持稳定,Ir溶解速率较未掺杂样品明显降低,证明了Ta掺杂大大提升了无定型氧化铱材料的稳定性.综上,本文发展了制备高价金属掺杂氧化铱的改性亚当斯熔融法,利用高价金属元素与氧的强成键作用,调控了铱活性位点的电子结构,同时提升了氧化铱类材料在酸性氧析出反应中的活性与稳定性,简化了此类材料的合成方式,为进一步降低质子交换膜电解水器件阳极催化剂的成本和提高其催化活性提供了新思路.展开更多
Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotentia...Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.展开更多
In this study,a combined system consisting of an anaerobic membrane bioreactor(AnMBR)and flow-through biofilm reactor/CANON(FTBR/CANON)was developed to simultaneously remove carbon and nitrogen from synthetic livestoc...In this study,a combined system consisting of an anaerobic membrane bioreactor(AnMBR)and flow-through biofilm reactor/CANON(FTBR/CANON)was developed to simultaneously remove carbon and nitrogen from synthetic livestock wastewater.The average removal efficiencies of total nitrogen(TN)were 64.2 and 76.4%with influent ammonium(NH4+-N)concentrations of approximately 200 and 500 mg/L,respectively.The COD removal efficiencies were higher than 98.0%during the entire operation.Mass balance analysis showed that COD and TN were mainly removed by the AnMBR and FTBR/CANON,respectively.The anammox process was the main nitrogen removal pathway in the combined system,with a contribution of over 80%.High functional bacterial activity was observed in the combined system.Particularly,an increase in the NH4+-N concentration considerably improved the anammox activity of the biofilm in the FTBR/CANON.16S rRNA high-throughput sequencing revealed that Methanosaeta,Candidatus Methanofastidiosum,and Methanobacterium were the dominant methanogens in the AnMBR granular sludge.In the CANON biofilm,Nitrosomonas and Candidatus Kuenenia were identified as aerobic and anaerobic ammonium-oxidizing bacteria,respectively.In summary,this study proposes a combined AnMBR and FTBR/CANON process targeting COD and nitrogen removal,and provides a potential alternative for treating high-strength wastewater.展开更多
The increasing application of anammox processes suggests their enormous potential for nitrogen removal in wastewater treatment facilities.However,the functional potentials and ecological differentiation of cooccurring...The increasing application of anammox processes suggests their enormous potential for nitrogen removal in wastewater treatment facilities.However,the functional potentials and ecological differentiation of cooccurring anammox species in complex ecosystems have not been well elucidated.Herein,by utilizing functional reconstruction and comparative genome analysis,we deciphered the cooccurring mechanisms of four Candidatus Brocadia species that were spontaneously enriched in a full-scale swine wastewater treatment system.Phylogenetic analysis indicated that species SW172 and SW745 were closely related to Ca.Brocadia caroliniensis and Ca.Brocadia sapporoensis,respectively,whereas the dominant species SW510 and SW773,with a total average abundance of 34.1%,were classified as novel species of the genus Ca.Brocadia.Functional reconstruction revealed that the novel species SW510 can encode both cytochrome cd1-type nitrite reductase and hydroxylamine oxidase for nitrite reduction.In contrast,the detected respiratory pentaheme cytochrome c nitrite reductase and acetate kinase genes suggested that SW773 likely reduced nitrite to ammonium with acetate as a carbon source.Intriguingly,the presence of genes encoding urease and cyanase indicated that both novel species can use diverse organic nitrogen compounds in addition to ammonia and nitrite as substrates.Taken together,the recovery and comparative analysis of these anammox genomes expand our understanding of the functional differentiation and cooccurrence of the genus Ca.Brocadia in wastewater treatment systems.展开更多
Perovskite-structured barium strontium titanate[Ba_(1-x)Sr_(x)Ti O_(3),x=0.1–0.9] films have been epitaxially fabricated by using a pulsed-laser deposition technique.The third-order nonlinear optical properties were ...Perovskite-structured barium strontium titanate[Ba_(1-x)Sr_(x)Ti O_(3),x=0.1–0.9] films have been epitaxially fabricated by using a pulsed-laser deposition technique.The third-order nonlinear optical properties were studied through a z-scan method,allowing the resolution of the nonlinear refractive and absorptive contributions to the responses.Although all the samples show almost the same value of nonlinear absorption coefficient,the extracted nonlinear refractive index of the sample of x=0.3 is apparently larger than that of other samples.Dependency of the nonlinear optical properties on the Ba/Sr ratio is discussed in terms of the crystal phase transformation and metal-oxygen bond length of the selected materials.展开更多
Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequenc...Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequence was assembled by combining Illumina short reads, Pacific Biosciences single-molecule real-time long reads, and Hi-C sequencing data. The size of tung tree genome is 1.12 Gb, with 28,422 predicted genes and over 73% repeat sequences. The V. fordii underwent an ancient genome triplication event shared by core eudicots but no further wholegenome duplication in the subsequent ca. 34.55 million years of evolutionary history of the tung tree lineage. Insertion time analysis revealed that repeat-driven genome expansion might have arisen as a result of long-standing long terminal repeat retrotransposon bursts and lack of efficient DNA deletion mechanisms. The genome harbors 88 resistance genes encoding nucleotide-binding sites;17 of these genes may be involved in early-infection stage of Fusarium wilt resistance. Further, 651 oil-related genes were identified, 88 of which are predicted to be directly involved in tung oil biosynthesis. Relatively few phosphoenolpyruvate carboxykinase genes, and synergistic effects between transcription factors and oil biosynthesis-related genes might contribute to the high oil content of tung seed. The tung tree genome constitutes a valuable resource for understanding genome evolution, as well as for molecular breeding and genetic improvements for oil production.展开更多
Eucommia ulmoides, also called hardy rubber tree, is an economically important tree; however, the lack of its genome sequence restricts the fundamental biological research and applied studies of this plant species. He...Eucommia ulmoides, also called hardy rubber tree, is an economically important tree; however, the lack of its genome sequence restricts the fundamental biological research and applied studies of this plant species. Here, we present a high-quality assembly of its ~l.2-Gb genome (scaffold N50 = 1.88 Mb) with at least 26 723 predicted genes for E. ulmoides, the first sequenced genome of the order Garryales, which was obtained using an integrated strategy combining Illumina sequencing, PacBio sequencing, and BioNano mapping. As a sister taxon to lamiids and campanulids, E. ulmoides underwent an ancient genome triplication shared by core eudicots but no further whole-genome duplication in the last ~125 million years. E. ulmoides exhibits high expression levels and/or gene number expansion for multiple genes involved in stress responses and the biosynthesis of secondary metabolites, which may account for its considerable environmental adaptability. In contrast to the rubber tree (Hevea brasiliensis), which produces cis-polyisoprene, E. ulmoides has evolved to synthe- size long-chain trans-polyisoprene via farnesyl diphosphate synthases (FPSs). Moreover, FPS and rub- ber elongation factor/small rubber particle protein gene families were expanded independently from the H. brasiliensis lineage. These results provide new insights into the biology of E. ulmoides and the origin of polyisoprene biosynthesis.展开更多
Because of the low access to biodegradable organic substances used for denitrification,the partial nitrification-denitrification process has been considered as a low-cost,sustainable alternative for landfill leachate ...Because of the low access to biodegradable organic substances used for denitrification,the partial nitrification-denitrification process has been considered as a low-cost,sustainable alternative for landfill leachate treatment.In this study,the process upgrade from conventional to partial nitrificationdenitrification was comprehensively investigated in a full-scale landfill leachate treatment plant(LLTP).The partial nitrification-denitrification system was successfully achieved through the optimizing dissolved oxygen and the external carbon source,with effluent nitrogen concentrations lower than 150 mg/L.Moreover,the upgrading process facilitated the enrichment of Nitrosomonas(abundance increased from 0.4%to 3.3%),which was also evidenced by increased abundance of amoA/B/C genes carried by Nitrosomonas.Although Nitrospira(accounting for 0.1%-0.6%)was found to stably exist in the reactor tank,considerable nitrite accumulation occurred in the reactor(reaching 98.8 mg/L),indicating high-efficiency of the partial nitrification process.Moreover,the abundance of Thauera,the dominant denitrifying bacteria responsible for nitrite reduction,gradually increased from 0.60%to 5.52%during the upgrade process.This process caused great changes in the microbial community,inducing continuous succession of heterotrophic bacteria accompanied by enhanced metabolic potentials toward organic substances.The results obtained in this study advanced our understanding of the operation of a partial nitrification-denitrification system and provided a technical case for the upgrade of currently existing full-scale LLTPs.展开更多
Diversified regulation of electrons have received much attention to realize a multi-functional transistor,and it is crucial to have a considerable control over the charge carriers in transistors.Ionic gel,as the diele...Diversified regulation of electrons have received much attention to realize a multi-functional transistor,and it is crucial to have a considerable control over the charge carriers in transistors.Ionic gel,as the dielectric material in transistors,facilitates a large capacitance,and high induced-carrier concentrations.This review presents the recent progress in ionic-gated transistors(IGTs)that have good mechanical stability as well as high physical and chemical stability.We first briefly introduce the various applications of IGTs in sensors,neuromorphic transistors,organic transistor circuits,and health detection.Finally,the future perspectives of IGTs are discussed and some possible solutions to the challenges are also proposed.展开更多
The genome sequence of Arabidopsis thaliana,a widely adopted model species,has greatly expedited plant molecular biology research.Over 20 years after the first release of the genome sequence(Arabidopsis Genome Initiat...The genome sequence of Arabidopsis thaliana,a widely adopted model species,has greatly expedited plant molecular biology research.Over 20 years after the first release of the genome sequence(Arabidopsis Genome Initiative,2000),there remains unresolved gap regions that are presumably composed of highly repetitive sequences,such as telomeres,centromeres,5S rDNA clusters,and nucleolar organizerregions(NORs)containing 45S rDNA.展开更多
The most common and abundant DNA modification is 5-methylcytosine(5mC),which has been well-established as an epigenetic mark regulating gene expression in eukaryotes(Jones,2012).Another DNA modification N^6-methyl...The most common and abundant DNA modification is 5-methylcytosine(5mC),which has been well-established as an epigenetic mark regulating gene expression in eukaryotes(Jones,2012).Another DNA modification N^6-methyldeoxyadenosine(6mA),previously reported as a widespread DNA methylation in prokaryotes.展开更多
The development of high-performance and cost-effective electrocatalysts towards oxygen reduction reaction(ORR) is of significant importance,but still challenging for the practical applications in related energy system...The development of high-performance and cost-effective electrocatalysts towards oxygen reduction reaction(ORR) is of significant importance,but still challenging for the practical applications in related energy systems.ORR process typically suffers from sluggish kinetics,the exploration of ORR electrocatalyst thus requires elaborate design.Herein,an effective strategy is developed for growing Co/N-doped carbon nanotube arrays on 2D MOFs-derived matrix via the pyrolysis of Co/Zn metalorganic-framework(MOF) nanosheets.The Co/Zn-MOF nanosheets serve as both the self-template for the 2D carbonized framework morphology and C/N source for the in-situ growth of 1D N-doped carbon nanotubes.The constructed hie rarchical architecture effectively integrates the OD/1D Co nanoparticle/Ndoped carbon nanotube interface and 1D(nanotubes)/2D(nanosheets) junction into frameworks with highly exposed active surface,enhanced mass-transport kinetics and electrical conductivity.As a result,the designed composite exhibits superior ORR activity and durability in alkaline media as compared to commercial Pt/C.Particularly,it shows promising ORR performance with a half-wave potential of 0.78 V versus reversible hydrogen electrode and negligible activity attenuation after 5000 potential cycles in acidic electrolyte.The designed strategy can be extended to construct other MOFs-derived carbon matrixes with diverse hierarchical structures and provide an efficient avenue for searching highperformance electrocatalysts.展开更多
Dear Editor,African swine fever(ASF)is one of the most pathogenic viral diseases in pigs caused by African swine fever virus(ASFV).The fatality rate is almost 100%,which brings huge economic losses to the hog industry...Dear Editor,African swine fever(ASF)is one of the most pathogenic viral diseases in pigs caused by African swine fever virus(ASFV).The fatality rate is almost 100%,which brings huge economic losses to the hog industry in countries with epiepidemics(Galindo and Alonso,2017).China was the first Asian country to have an ASF epidemic,and it spread quickly across the country after the first epidemic was re・ported in August 2018(Ge et al.,2018).After that,Mongolia,Vietnam,Cambodia and North Korea also reported on the ASF epidemic in succession(OIE,2019).展开更多
Genome sequencing has shown strong capabilities in the initial stages of the COVID-19 pandemic such as pathogen identification and virus preliminary tracing.While the rapid acquisition of SARS-Co V-2 genome from clini...Genome sequencing has shown strong capabilities in the initial stages of the COVID-19 pandemic such as pathogen identification and virus preliminary tracing.While the rapid acquisition of SARS-Co V-2 genome from clinical specimens is limited by their low nucleic acid load and the complexity of the nucleic acid background.To address this issue,we modified and evaluated an approach by utilizing SARS-Co V-2-specific amplicon amplification and Oxford Nanopore Prometh ION platform.This workflow started with the throat swab of the COVID-19 patient,combined reverse transcript PCR,and multi-amplification in one-step to shorten the experiment time,then can quickly and steadily obtain high-quality SARS-Co V-2 genome within 24 h.A comprehensive evaluation of the method was conducted in 42 samples:the sequencing quality of the method was correlated well with the viral load of the samples;high-quality SARS-Co V-2 genome could be obtained stably in the samples with Ct value up to 39.14;data yielding for different Ct values were assessed and the recommended sequencing time was 8 h for samples with Ct value of less than 20;variation analysis indicated that the method can detect the existing and emerging genomic mutations as well;Illumina sequencing verified that ultra-deep sequencing can greatly improve the single read error rate of Nanopore sequencing,making it as low as 0.4/10,000 bp.In summary,high-quality SARS-Co V-2 genome can be acquired by utilizing the amplicon amplification and it is an effective method in accelerating the acquisition of genetic resources and tracking the genome diversity of SARSCo V-2.展开更多
Global biodiversity is undergoing dramatic loss,mostly due to anthropogenic actions and climate change.Around 2.3seed plants died out each year in the past 2.5 centuries(Humphreys et al.,2019).Current species extincti...Global biodiversity is undergoing dramatic loss,mostly due to anthropogenic actions and climate change.Around 2.3seed plants died out each year in the past 2.5 centuries(Humphreys et al.,2019).Current species extinction rates are about 1,000 times the likely background rate of extinction(Pimm et al.,2014).展开更多
The revolution of biotechnology has pushed forward life sciences into the Big Data era.Particularly,high-throughput bio-techniques have greatly accelerated the integration of biology,computing and informatics,and henc...The revolution of biotechnology has pushed forward life sciences into the Big Data era.Particularly,high-throughput bio-techniques have greatly accelerated the integration of biology,computing and informatics,and hence substantially pushed forward the development of bioinformatics and computational biology.According to the latest report of data deposition within National Centre for Biotechnology Information(NCBI),the genome sequencing projects have increased 49.94%.展开更多
The importance of structural variants(SVs)for human phenotypes and diseases is now recognized.Although a variety of SV detection platforms and strategies that vary in sensitivity and specificity have been developed,fe...The importance of structural variants(SVs)for human phenotypes and diseases is now recognized.Although a variety of SV detection platforms and strategies that vary in sensitivity and specificity have been developed,few benchmarking procedures are available to confidently assess their performances in biological and clinical research.To facilitate the validation and application of these SV detection approaches,we established an Asian reference material by characterizing the genome of an Epstein-Barr virus(EBV)-immortalized B lymphocyte line along with identified benchmark regions and high-confidence SV calls.We established a high-confidence SV callset with 8938 SVs by integrating four alignment-based SV callers,including 109×Pacific Bio sciences(PacBio)continuous long reads(CLRs),22×PacBio circular consensus sequencing(CCS)reads,104×Oxford Nanopore Technologies(ONT)long reads,and 114×Bionano optical mapping platform,and one de novo assembly-based SV caller using CCS reads.A total of 544 randomly selected SVs were validated by PCR amplification and Sanger sequencing,demonstrating the robustness of our SV calls.Combining trio-binning-based haplotype assemblies,we established an SV benchmark for identifying false negatives and false positives by constructing the continuous high-confidence regions(CHCRs),which covered 1.46 gigabase pairs(Gb)and 6882 SVs supported by at least one diploid haplotype assembly.Establishing high-confidence SV calls for a benchmark sample that has been characterized by multiple technologies provides a valuable resource for investigating SVs in human biology,disease,and clinical research.展开更多
Dear Editor,It has been more than 1 year since China reported the first case of African swine fever (ASF) infection in August2018, and the epidemic situation remains severe (China News Service 2019). According to repo...Dear Editor,It has been more than 1 year since China reported the first case of African swine fever (ASF) infection in August2018, and the epidemic situation remains severe (China News Service 2019). According to reports from the Ministry of Agriculture and Rural Affairs, China has reported 160 cases of ASF, which resulted in nearly 1.2 million pigs being killed, as of November 21, 2019 (China News Service 2019).展开更多
Correction to:Virologica Sinica(2021)36:901-912 https://doi.Org/10.1007/sl 2250-021-00378-8 The original version of article contains errors in Figure 4,Supplementary Figure S2,Supplementary Table S2,and the correspond...Correction to:Virologica Sinica(2021)36:901-912 https://doi.Org/10.1007/sl 2250-021-00378-8 The original version of article contains errors in Figure 4,Supplementary Figure S2,Supplementary Table S2,and the corresponding description in part 3 of“Results”section.展开更多
基金supported by the National Key R&D Program of China(2022YFB2404300)the National Natural Science Foundation of China(NSFC Nos.52177217 and 52106244)。
文摘Providing early safety warning for batteries in real-world applications is challenging.In this study,comprehensive thermal abuse experiments are conducted to clarify the multidimensional signal evolution of battery failure under various preload forces.The time-sequence relationship among expansion force,voltage,and temperature during thermal abuse under five categorised stages is revealed.Three characteristic peaks are identified for the expansion force,which correspond to venting,internal short-circuiting,and thermal runaway.In particular,an abnormal expansion force signal can be detected at temperatures as low as 42.4°C,followed by battery thermal runaway in approximately 6.5 min.Moreover,reducing the preload force can improve the effectiveness of the early-warning method via the expansion force.Specifically,reducing the preload force from 6000 to 1000 N prolongs the warning time(i.e.,227 to 398 s)before thermal runaway is triggered.Based on the results,a notable expansion force early-warning method is proposed that can successfully enable early safety warning approximately 375 s ahead of battery thermal runaway and effectively prevent failure propagation with module validation.This study provides a practical reference for the development of timely and accurate early-warning strategies as well as guidance for the design of safer battery systems.
文摘氢能作为一种潜在的能源载体,有望取代化石燃料,解决当今社会的能源需求和环境问题.质子交换膜电解水(PEMWE)技术因其工作电流密度大、氢气纯度高和系统响应迅速等优点,能够有效地弥补可再生能源波动性等缺点,被认为是一种利用可再生能源制氢的可持续手段.但其阳极氧析出反应(OER)为四电子/质子转移过程,反应动力学缓慢,同时强氧化性和强酸性环境会对阳极催化剂的产生腐蚀,导致稳定性差,因此亟需开发高效且稳定的催化剂.研究发现,无定型氧化铱材料中的特殊缺陷结构可显著提升其催化酸性OER的活性,但该结构也会加速反应过程中铱的溶解,导致催化剂稳定性降低,严重限制了其实际应用.本文采用高价金属掺杂的策略,利用高价金属元素与氧的强成键作用,对无定型氧化铱的整体结构及活性位点起到优化且稳定的作用.首先,采用改性的亚当斯熔融法制备了金属钽掺杂的无定型氧化铱:350-Ta@IrO_(x),400-Ta@IrO_(x),450-Ta@IrO_(x)(350,400和450代表样品分别在350,400和450℃烧结),并用于催化酸性OER;作为对比,制备了无掺杂的无定型氧化铱:350-IrO_(x),400-IrO_(x)和450-IrO_(x).然后,通过扫描电子显微镜、透射电子显微镜(TEM)和X射线衍射等表征技术考察了材料的宏观形貌及微观结构.结果表明,掺杂后的350-Ta@IrO_(x)材料表面具有丰富的氧空位贡献的活性位点,且表现出多晶的超小纳米颗粒形貌.电化学测试结果表明,350-Ta@IrO_(x)具有较好的酸性OER活性,在10 mA cm-2的电流密度下,过电势仅为223 mV,在1.55 V vs.RHE的电位下质量活性为1207.4 A gIr-1,是商业二氧化铱的147.7倍.且该催化剂的稳定性比未掺杂Ta样品及商业二氧化铱有明显提升,在0.5 mol L^(-1)硫酸溶液中反应500 h后电位未发生明显变化.密度泛函理论计算结果表明,Ta掺杂与构建缺陷有利于OER决速步中水分子的亲核进攻,从而提升催化活性并降低反应过电势.为进一步研究材料在酸性OER工作状态下具有较好稳定性的原因,采用TEM和X射线光电子能谱等对反应前后的材料进行表征.结果表明,350-Ta@IrO_(x)在反应前后结构保持稳定,Ir溶解速率较未掺杂样品明显降低,证明了Ta掺杂大大提升了无定型氧化铱材料的稳定性.综上,本文发展了制备高价金属掺杂氧化铱的改性亚当斯熔融法,利用高价金属元素与氧的强成键作用,调控了铱活性位点的电子结构,同时提升了氧化铱类材料在酸性氧析出反应中的活性与稳定性,简化了此类材料的合成方式,为进一步降低质子交换膜电解水器件阳极催化剂的成本和提高其催化活性提供了新思路.
基金This work was supported by National Key R&D Program of China(2020YFE0204500)the National Natural Science Foundation of China(52273277,52072362,52071311)+1 种基金Jilin Province Science and Technology Development Plan Funding Project(20220201112GX)Youth Innovation Promotion Association CAS(2020230 and 2021223).H.X.Z.thanks funding from National Natural Science Foundation of China Outstanding Youth Science Foundation of China(Overseas).These authors thank the staff of beamline BL13SSW at Shanghai Synchrotron Radiation Facility for experiments supports.The authors also gratefully appreciate the support of the morphology characterization and analysis from Prof.Jiuhui Han(Tianjin University of Technology).
文摘Supported metal clusters with the integrated advantages of single-atom catalysts and conventional nanoparticles held great promise in the electrocatalytic carbon dioxide reduction(ECO_(2)R)operated at low overpotential and high current density.However,its precise synthesis and the understanding of synergisti-cally catalytic effects remain challenging.Herein,we report a facile method to synthesize the bimetallic Cu and Ni clusters anchored on porous carbon(Cu/Ni-NC)and achieve an enhanced ECO_(2)R.The aberration-corrected high-angle annular dark-field scanning transmission electron microscopy and synchrotron X-ray absorption spectroscopy were employed to verify the metal dispersion and the coordination of Cu/Ni clusters on NC.As a result of this route,the target Cu/Ni-NC exhibits excellent electrocatalytic performance including a stable 30 h electrolysis at 200 mA cm^(-2) with carbon monoxide Faradaic efficiency of∼95.1%using a membrane electrode assembly electrolysis cell.Combined with the in situ analysis of the surface-enhanced Fourier transform infrared spectroelectrochemistry,we propose that the synergistic effects between Ni and Cu can effectively promote the H_(2)O dissociation,thereby accelerate the hydrogenation of CO_(2)to*COOH and the overall reaction process.
基金supported by the National Natural Science Foundation of China(nos.32161143031,22376228 and 52200081)the Fundamental Research Funds for the Central Universities(Sun Yat-sen University,23lgzy005).
文摘In this study,a combined system consisting of an anaerobic membrane bioreactor(AnMBR)and flow-through biofilm reactor/CANON(FTBR/CANON)was developed to simultaneously remove carbon and nitrogen from synthetic livestock wastewater.The average removal efficiencies of total nitrogen(TN)were 64.2 and 76.4%with influent ammonium(NH4+-N)concentrations of approximately 200 and 500 mg/L,respectively.The COD removal efficiencies were higher than 98.0%during the entire operation.Mass balance analysis showed that COD and TN were mainly removed by the AnMBR and FTBR/CANON,respectively.The anammox process was the main nitrogen removal pathway in the combined system,with a contribution of over 80%.High functional bacterial activity was observed in the combined system.Particularly,an increase in the NH4+-N concentration considerably improved the anammox activity of the biofilm in the FTBR/CANON.16S rRNA high-throughput sequencing revealed that Methanosaeta,Candidatus Methanofastidiosum,and Methanobacterium were the dominant methanogens in the AnMBR granular sludge.In the CANON biofilm,Nitrosomonas and Candidatus Kuenenia were identified as aerobic and anaerobic ammonium-oxidizing bacteria,respectively.In summary,this study proposes a combined AnMBR and FTBR/CANON process targeting COD and nitrogen removal,and provides a potential alternative for treating high-strength wastewater.
基金supported by the National Natural Science Foundation of China(Nos.52000185,51878675,and 51622813)the Natural Science Foundation of Guangdong Province(No.2021A1515010512)the Fundamental Research Funds for the Central Universities,Sun Yat-sen University(No.2021qntd07).
文摘The increasing application of anammox processes suggests their enormous potential for nitrogen removal in wastewater treatment facilities.However,the functional potentials and ecological differentiation of cooccurring anammox species in complex ecosystems have not been well elucidated.Herein,by utilizing functional reconstruction and comparative genome analysis,we deciphered the cooccurring mechanisms of four Candidatus Brocadia species that were spontaneously enriched in a full-scale swine wastewater treatment system.Phylogenetic analysis indicated that species SW172 and SW745 were closely related to Ca.Brocadia caroliniensis and Ca.Brocadia sapporoensis,respectively,whereas the dominant species SW510 and SW773,with a total average abundance of 34.1%,were classified as novel species of the genus Ca.Brocadia.Functional reconstruction revealed that the novel species SW510 can encode both cytochrome cd1-type nitrite reductase and hydroxylamine oxidase for nitrite reduction.In contrast,the detected respiratory pentaheme cytochrome c nitrite reductase and acetate kinase genes suggested that SW773 likely reduced nitrite to ammonium with acetate as a carbon source.Intriguingly,the presence of genes encoding urease and cyanase indicated that both novel species can use diverse organic nitrogen compounds in addition to ammonia and nitrite as substrates.Taken together,the recovery and comparative analysis of these anammox genomes expand our understanding of the functional differentiation and cooccurrence of the genus Ca.Brocadia in wastewater treatment systems.
基金supported by the National Natural Science Foundation of China(No.10704065)the Graduate Innovation Foundation of Yantai University(No.KGIFYTU2212)。
文摘Perovskite-structured barium strontium titanate[Ba_(1-x)Sr_(x)Ti O_(3),x=0.1–0.9] films have been epitaxially fabricated by using a pulsed-laser deposition technique.The third-order nonlinear optical properties were studied through a z-scan method,allowing the resolution of the nonlinear refractive and absorptive contributions to the responses.Although all the samples show almost the same value of nonlinear absorption coefficient,the extracted nonlinear refractive index of the sample of x=0.3 is apparently larger than that of other samples.Dependency of the nonlinear optical properties on the Ba/Sr ratio is discussed in terms of the crystal phase transformation and metal-oxygen bond length of the selected materials.
基金supported by the National Key R&D Program of China(Grant No.2017YFD0600703)the National Forestry Public Welfare Industry Research Project of China(Grant No.201204403)+2 种基金the Outstanding Youth Project of the Education Department of Hunan Province,China(Grant No.17B279)the US Department of AgricultureAgricultural Research Service(USDA-ARS)National Program for Quality and Utilization of Agricultural Products(NP 306Grant No.CRIS 6054-41000-103-00-D).
文摘Tung tree(Vernicia fordii) is an economically important woody oil plant that produces tung oil rich in eleostearic acid. Here, we report a high-quality chromosome-scale genome sequence of tung tree. The genome sequence was assembled by combining Illumina short reads, Pacific Biosciences single-molecule real-time long reads, and Hi-C sequencing data. The size of tung tree genome is 1.12 Gb, with 28,422 predicted genes and over 73% repeat sequences. The V. fordii underwent an ancient genome triplication event shared by core eudicots but no further wholegenome duplication in the subsequent ca. 34.55 million years of evolutionary history of the tung tree lineage. Insertion time analysis revealed that repeat-driven genome expansion might have arisen as a result of long-standing long terminal repeat retrotransposon bursts and lack of efficient DNA deletion mechanisms. The genome harbors 88 resistance genes encoding nucleotide-binding sites;17 of these genes may be involved in early-infection stage of Fusarium wilt resistance. Further, 651 oil-related genes were identified, 88 of which are predicted to be directly involved in tung oil biosynthesis. Relatively few phosphoenolpyruvate carboxykinase genes, and synergistic effects between transcription factors and oil biosynthesis-related genes might contribute to the high oil content of tung seed. The tung tree genome constitutes a valuable resource for understanding genome evolution, as well as for molecular breeding and genetic improvements for oil production.
文摘Eucommia ulmoides, also called hardy rubber tree, is an economically important tree; however, the lack of its genome sequence restricts the fundamental biological research and applied studies of this plant species. Here, we present a high-quality assembly of its ~l.2-Gb genome (scaffold N50 = 1.88 Mb) with at least 26 723 predicted genes for E. ulmoides, the first sequenced genome of the order Garryales, which was obtained using an integrated strategy combining Illumina sequencing, PacBio sequencing, and BioNano mapping. As a sister taxon to lamiids and campanulids, E. ulmoides underwent an ancient genome triplication shared by core eudicots but no further whole-genome duplication in the last ~125 million years. E. ulmoides exhibits high expression levels and/or gene number expansion for multiple genes involved in stress responses and the biosynthesis of secondary metabolites, which may account for its considerable environmental adaptability. In contrast to the rubber tree (Hevea brasiliensis), which produces cis-polyisoprene, E. ulmoides has evolved to synthe- size long-chain trans-polyisoprene via farnesyl diphosphate synthases (FPSs). Moreover, FPS and rub- ber elongation factor/small rubber particle protein gene families were expanded independently from the H. brasiliensis lineage. These results provide new insights into the biology of E. ulmoides and the origin of polyisoprene biosynthesis.
基金We acknowledge the National Key R&D Program of China(No.2017YFE0114300)Special Fund for Science and Technology Innovation Strategy of Guangdong Province(No.2018B020202)+1 种基金Natural Science Foundation of Guangdong Province(No.2018A030310246)National Natural Science Foundation of China(Nos.21607177,51622813 and 51808564)for financially supporting this study.
文摘Because of the low access to biodegradable organic substances used for denitrification,the partial nitrification-denitrification process has been considered as a low-cost,sustainable alternative for landfill leachate treatment.In this study,the process upgrade from conventional to partial nitrificationdenitrification was comprehensively investigated in a full-scale landfill leachate treatment plant(LLTP).The partial nitrification-denitrification system was successfully achieved through the optimizing dissolved oxygen and the external carbon source,with effluent nitrogen concentrations lower than 150 mg/L.Moreover,the upgrading process facilitated the enrichment of Nitrosomonas(abundance increased from 0.4%to 3.3%),which was also evidenced by increased abundance of amoA/B/C genes carried by Nitrosomonas.Although Nitrospira(accounting for 0.1%-0.6%)was found to stably exist in the reactor tank,considerable nitrite accumulation occurred in the reactor(reaching 98.8 mg/L),indicating high-efficiency of the partial nitrification process.Moreover,the abundance of Thauera,the dominant denitrifying bacteria responsible for nitrite reduction,gradually increased from 0.60%to 5.52%during the upgrade process.This process caused great changes in the microbial community,inducing continuous succession of heterotrophic bacteria accompanied by enhanced metabolic potentials toward organic substances.The results obtained in this study advanced our understanding of the operation of a partial nitrification-denitrification system and provided a technical case for the upgrade of currently existing full-scale LLTPs.
基金supported by the National Science Foundation of China(NSFC,Grant No.61625404,61874111,61888102,62022079)Young Elite Scientists Sponsorship Program by CAST(2018QNRC001)the Youth Innovation Promotion Association of Chinese Academy of Sciences under Grant No.2020115.
文摘Diversified regulation of electrons have received much attention to realize a multi-functional transistor,and it is crucial to have a considerable control over the charge carriers in transistors.Ionic gel,as the dielectric material in transistors,facilitates a large capacitance,and high induced-carrier concentrations.This review presents the recent progress in ionic-gated transistors(IGTs)that have good mechanical stability as well as high physical and chemical stability.We first briefly introduce the various applications of IGTs in sensors,neuromorphic transistors,organic transistor circuits,and health detection.Finally,the future perspectives of IGTs are discussed and some possible solutions to the challenges are also proposed.
文摘The genome sequence of Arabidopsis thaliana,a widely adopted model species,has greatly expedited plant molecular biology research.Over 20 years after the first release of the genome sequence(Arabidopsis Genome Initiative,2000),there remains unresolved gap regions that are presumably composed of highly repetitive sequences,such as telomeres,centromeres,5S rDNA clusters,and nucleolar organizerregions(NORs)containing 45S rDNA.
基金supported by Recruitment program of Global Youth Expert of China (to X.G.)the Elite Youth Program of the Chinese Academy of Agricultural Science (to X.G.)the intramural research support from Biotechnology Research Institute, Chinese Academy of Agricultural Sciences
文摘The most common and abundant DNA modification is 5-methylcytosine(5mC),which has been well-established as an epigenetic mark regulating gene expression in eukaryotes(Jones,2012).Another DNA modification N^6-methyldeoxyadenosine(6mA),previously reported as a widespread DNA methylation in prokaryotes.
基金supported by the National Natural Science Foundation of China (NSFC,Nos.21701124 and 51702236)Tianjin Municipal Science and Technology Commission (Nos. 18TCQNJC71500 and 17JCZDJC38000)the National Key R&D Program of China (No.2017YFA0700104)。
文摘The development of high-performance and cost-effective electrocatalysts towards oxygen reduction reaction(ORR) is of significant importance,but still challenging for the practical applications in related energy systems.ORR process typically suffers from sluggish kinetics,the exploration of ORR electrocatalyst thus requires elaborate design.Herein,an effective strategy is developed for growing Co/N-doped carbon nanotube arrays on 2D MOFs-derived matrix via the pyrolysis of Co/Zn metalorganic-framework(MOF) nanosheets.The Co/Zn-MOF nanosheets serve as both the self-template for the 2D carbonized framework morphology and C/N source for the in-situ growth of 1D N-doped carbon nanotubes.The constructed hie rarchical architecture effectively integrates the OD/1D Co nanoparticle/Ndoped carbon nanotube interface and 1D(nanotubes)/2D(nanosheets) junction into frameworks with highly exposed active surface,enhanced mass-transport kinetics and electrical conductivity.As a result,the designed composite exhibits superior ORR activity and durability in alkaline media as compared to commercial Pt/C.Particularly,it shows promising ORR performance with a half-wave potential of 0.78 V versus reversible hydrogen electrode and negligible activity attenuation after 5000 potential cycles in acidic electrolyte.The designed strategy can be extended to construct other MOFs-derived carbon matrixes with diverse hierarchical structures and provide an efficient avenue for searching highperformance electrocatalysts.
基金supported by the National Key R&D Program of China (2016YFC1200800 & 2018YFC0840402)Research Project of African Swine Fever of Chinese Academy of Sciences (KJZD-SWL06)+2 种基金China Mega-Project for Infectious Disease (2017ZX10103005-005)the State Key Laboratory of Veterinary Biotechnology Research Fund (SKLVBF201902)supported by Youth Innovation Promotion Association of CAS (2019091)
文摘Dear Editor,African swine fever(ASF)is one of the most pathogenic viral diseases in pigs caused by African swine fever virus(ASFV).The fatality rate is almost 100%,which brings huge economic losses to the hog industry in countries with epiepidemics(Galindo and Alonso,2017).China was the first Asian country to have an ASF epidemic,and it spread quickly across the country after the first epidemic was re・ported in August 2018(Ge et al.,2018).After that,Mongolia,Vietnam,Cambodia and North Korea also reported on the ASF epidemic in succession(OIE,2019).
基金supported by grants from the Foundation for National Mega Project on Major Infectious Disease Prevention(grant number 2017ZX10103005-005)National Key Research and Development Program of China(2020YFC0845800 and 2020YFC0845600)the National Natural Science Foundation of China(31970548 and 91631110)。
文摘Genome sequencing has shown strong capabilities in the initial stages of the COVID-19 pandemic such as pathogen identification and virus preliminary tracing.While the rapid acquisition of SARS-Co V-2 genome from clinical specimens is limited by their low nucleic acid load and the complexity of the nucleic acid background.To address this issue,we modified and evaluated an approach by utilizing SARS-Co V-2-specific amplicon amplification and Oxford Nanopore Prometh ION platform.This workflow started with the throat swab of the COVID-19 patient,combined reverse transcript PCR,and multi-amplification in one-step to shorten the experiment time,then can quickly and steadily obtain high-quality SARS-Co V-2 genome within 24 h.A comprehensive evaluation of the method was conducted in 42 samples:the sequencing quality of the method was correlated well with the viral load of the samples;high-quality SARS-Co V-2 genome could be obtained stably in the samples with Ct value up to 39.14;data yielding for different Ct values were assessed and the recommended sequencing time was 8 h for samples with Ct value of less than 20;variation analysis indicated that the method can detect the existing and emerging genomic mutations as well;Illumina sequencing verified that ultra-deep sequencing can greatly improve the single read error rate of Nanopore sequencing,making it as low as 0.4/10,000 bp.In summary,high-quality SARS-Co V-2 genome can be acquired by utilizing the amplicon amplification and it is an effective method in accelerating the acquisition of genetic resources and tracking the genome diversity of SARSCo V-2.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB3100000)。
文摘Global biodiversity is undergoing dramatic loss,mostly due to anthropogenic actions and climate change.Around 2.3seed plants died out each year in the past 2.5 centuries(Humphreys et al.,2019).Current species extinction rates are about 1,000 times the likely background rate of extinction(Pimm et al.,2014).
文摘The revolution of biotechnology has pushed forward life sciences into the Big Data era.Particularly,high-throughput bio-techniques have greatly accelerated the integration of biology,computing and informatics,and hence substantially pushed forward the development of bioinformatics and computational biology.According to the latest report of data deposition within National Centre for Biotechnology Information(NCBI),the genome sequencing projects have increased 49.94%.
基金supported by grants from the National Key R&D Program of China(Grant No.2017YFC0906501)。
文摘The importance of structural variants(SVs)for human phenotypes and diseases is now recognized.Although a variety of SV detection platforms and strategies that vary in sensitivity and specificity have been developed,few benchmarking procedures are available to confidently assess their performances in biological and clinical research.To facilitate the validation and application of these SV detection approaches,we established an Asian reference material by characterizing the genome of an Epstein-Barr virus(EBV)-immortalized B lymphocyte line along with identified benchmark regions and high-confidence SV calls.We established a high-confidence SV callset with 8938 SVs by integrating four alignment-based SV callers,including 109×Pacific Bio sciences(PacBio)continuous long reads(CLRs),22×PacBio circular consensus sequencing(CCS)reads,104×Oxford Nanopore Technologies(ONT)long reads,and 114×Bionano optical mapping platform,and one de novo assembly-based SV caller using CCS reads.A total of 544 randomly selected SVs were validated by PCR amplification and Sanger sequencing,demonstrating the robustness of our SV calls.Combining trio-binning-based haplotype assemblies,we established an SV benchmark for identifying false negatives and false positives by constructing the continuous high-confidence regions(CHCRs),which covered 1.46 gigabase pairs(Gb)and 6882 SVs supported by at least one diploid haplotype assembly.Establishing high-confidence SV calls for a benchmark sample that has been characterized by multiple technologies provides a valuable resource for investigating SVs in human biology,disease,and clinical research.
基金supported by the Research Project of African Swine Fever of Chinese Academy of Sciences (KJZD-SWL06)the National Natural Science Foundation of China (31941015)+3 种基金the National Key R&D Program of China (2016YFC1200800&2018YFC0840402)the China Mega-Project for Infectious Disease(2017ZX10103005-005)the State Key Laboratory of Veterinary Biotechnology Research Fund (SKLVBF201902)supported by Youth Innovation Promotion Association of CAS (2019091)。
文摘Dear Editor,It has been more than 1 year since China reported the first case of African swine fever (ASF) infection in August2018, and the epidemic situation remains severe (China News Service 2019). According to reports from the Ministry of Agriculture and Rural Affairs, China has reported 160 cases of ASF, which resulted in nearly 1.2 million pigs being killed, as of November 21, 2019 (China News Service 2019).
文摘Correction to:Virologica Sinica(2021)36:901-912 https://doi.Org/10.1007/sl 2250-021-00378-8 The original version of article contains errors in Figure 4,Supplementary Figure S2,Supplementary Table S2,and the corresponding description in part 3 of“Results”section.