The effects of different proportions of La and Y elements in the A-side on the structure and properties of A_(2)B_(7)-type La-Y-Ni hydrogen storage alloys were investigated.The(La,Y)_(2)Ni_(7)hydrogen storage alloys w...The effects of different proportions of La and Y elements in the A-side on the structure and properties of A_(2)B_(7)-type La-Y-Ni hydrogen storage alloys were investigated.The(La,Y)_(2)Ni_(7)hydrogen storage alloys with different La/Y ratios were prepared by sintering the Y_(2)Ni_(4)precursor and different AB_(5)-type precursors at 1298 K for 5 h and subsequently annealed for 20 h at 1248 K.All the alloys only contain Ce_(2)Ni_(7)(2H-type)and Gd_(2)Co_(7)(3R-type)phases with different mass ratios.As the La/Y ratio decreases,the cell volume of the two phases declines and the corresponding plateau pressure gradually increases.As the proportion of Y in the alloy increases,the hydrogen storage capacity increases gradually from 1.309 wt%(La/Y=1/1)to 1.713 wt%(La/Y=1/5)and the high-rate discharge(HRD1500)ability of the alloy electrodes increases gradually from 62.7%(La/Y=1/1)to 88.6%(La/Y=1/5).The hydrogen diffusion rate in the bulk of the alloy is the controlling step of hydriding/dehydriding kinetics.The Y ele ment can effectively inhibit the hydrogen-induced amorphous(HIA)of La-Y-Ni alloys,but the poor stability of the Y element in alkaline KOH aqueous solution leads to a decrease in the electrochemical cyclic stability with increasing Y content.展开更多
Selective oxidation of biomass and its derivatives to dicarboxylic acids represents a promising route for biomass valorization.However,the co-presence of multiple functional groups in biomass molecules makes the selec...Selective oxidation of biomass and its derivatives to dicarboxylic acids represents a promising route for biomass valorization.However,the co-presence of multiple functional groups in biomass molecules makes the selective oxidation of particular functional a challenging task.Here,we demonstrate an efficient electrocatalytic system consisting of nickel oxide(NiO)and a nitroxyl radical,i.e.,2,2,6,6-tetrame thylpiperidine-1-oxyl(TEMPO)or 4-acetamido-TEMPO(ACT),for the selective oxidation of key bioplatform molecules including glucose,xylose and 5-hydroxymethylfurfural(HMF)into corresponding dicarboxylic acids,i.e.,glucaric acid,xylaric acid,and 2,5-furandicarboxylic acid(FDCA).NiO is clarified as the active catalyst for the oxidation of aldehyde in bio-platform molecules to carboxylic acid,while TEMPO or ACT is responsible for the oxidation of primary alcohol to aldehyde.The combination of NiO and TEMPO or ACT significantly accelerated the tandem oxidation of aldehyde and hydroxyl groups in glucose,xylose and HMF,thus achieving excellent yields(83%-99%)of dicarboxylic acids.Moreover,the combination catalyst enables the selective oxidation of glucose and xylose with high concentrations(e.g.,20 wt%),which offers a promising strategy for biomass valorization.展开更多
Coronavirus(CoV)spillover originating from game animals,particularly pangolins,is currently a significant concern.Meanwhile,vigilance is urgently needed for coronaviruses carried by bats,which are known as natural res...Coronavirus(CoV)spillover originating from game animals,particularly pangolins,is currently a significant concern.Meanwhile,vigilance is urgently needed for coronaviruses carried by bats,which are known as natural reservoirs of many coronaviruses.In this study,we collected 729 anal swabs of 20 different bat species from nine locations in Yunnan and Guangdong provinces,southern China,in 2016 and 2017,and described the molecular characteristics and genetic diversity of alphacoronaviruses(αCoVs)and betacoronaviruses(βCoVs)found in these bats.Using RT-PCR,we identified 58(8.0%)bat CoVs in nine bat species from six locations.Furthermore,using the Illumina platform,we obtained two representative full-length genomes of the bat CoVs,namely TyRo-CoV-162275 and TyRo-CoV-162269.Sequence analysis showed that TyRo-CoV-162275 shared the highest identity with Malayan pangolin(Manis javanica)HKU4-related coronaviruses(MjHKU4r-CoVs)from Guangxi Province,whereas TyRo-CoV-162269 was closely related to HKU33-CoV discovered in a greater bamboo bat(Tylonycteris robustula)from Guizhou Province.Notably,TyRo-CoV-162275 has a putative furin protease cleavage site in its S protein and is likely to utilize human dipeptidyl peptidase-4(hDPP4)as a cell-entry receptor,similar to MERSCoV.To the best of our knowledge,this is the first report of a bat HKU4r-CoV strain containing a furin protease cleavage site.These findings expand our understanding of coronavirus geographic and host distributions.展开更多
Bats carry a variety of viruses, and some of them cause public health problems. Macao, which is famous for its gambling industry, has a complex population structure. The globalization in such an international metropol...Bats carry a variety of viruses, and some of them cause public health problems. Macao, which is famous for its gambling industry, has a complex population structure. The globalization in such an international metropolis has enhanced the chance of disease transmission. Therefore, surveillance of zoonotic viruses is necessary for the early warning of potential emerging infectious diseases.Here, we report the first surveillance of bat viruses in Macao. In this study, we collected 1004 samples involving 10 bat species from 7 sites from April 2015 to May 2016, and examined the presence of viruses using nucleic acid-based methods. Coronaviruses, adenoviruses and paramyxoviruses were detected in these samples, with a high prevalence of coronaviruses. While,none was positive for hepatitis A virus, hepatitis E virus or hantavirus. Co-infections are not common in those bat species, but coronavirus HKU6 and adenovirus can be found commonly occurred in Myotis ricketti.展开更多
In complex multivariate data sets,different features usually include diverse associations with different variables,and different variables are associated within different regions.Therefore,exploring the associations b...In complex multivariate data sets,different features usually include diverse associations with different variables,and different variables are associated within different regions.Therefore,exploring the associations between variables and voxels locally becomes necessary to better understand the underlying phenomena.In this paper,we propose a co-analysis framework based on biclusters,which are two subsets of variables and voxels with close scalar-value relationships,to guide the process of visually exploring multivariate data.We first automatically extract all meaningful biclusters,each of which only contains voxels with a similar scalar-value pattern over a subset of variables.These biclusters are organized according to their variable sets,and biclusters in each variable set are further grouped by a similarity metric to reduce redundancy and support diversity during visual exploration.Biclusters are visually represented in coordinated views to facilitate interactive exploration of multivariate data from the similarity between biclusters and the correlation of scalar values with different variables.Experiments on several representative multivariate scientific data sets demonstrate the effectiveness of our framework in exploring local relationships among variables,biclusters and scalar values in the data.展开更多
基金Project supported by the National Natural Science Foundation of China(51961002)National Key Research and Development Projects of China(2018YFE124400)+2 种基金Natural Science Foundation of Inner Mongolia(2020MS05013,2018MS05016)Science and Technology Program of Inner Mongolia(2020B2156)Special Project of Achievement Transformation in Inner Mongolia(2019CG082)。
文摘The effects of different proportions of La and Y elements in the A-side on the structure and properties of A_(2)B_(7)-type La-Y-Ni hydrogen storage alloys were investigated.The(La,Y)_(2)Ni_(7)hydrogen storage alloys with different La/Y ratios were prepared by sintering the Y_(2)Ni_(4)precursor and different AB_(5)-type precursors at 1298 K for 5 h and subsequently annealed for 20 h at 1248 K.All the alloys only contain Ce_(2)Ni_(7)(2H-type)and Gd_(2)Co_(7)(3R-type)phases with different mass ratios.As the La/Y ratio decreases,the cell volume of the two phases declines and the corresponding plateau pressure gradually increases.As the proportion of Y in the alloy increases,the hydrogen storage capacity increases gradually from 1.309 wt%(La/Y=1/1)to 1.713 wt%(La/Y=1/5)and the high-rate discharge(HRD1500)ability of the alloy electrodes increases gradually from 62.7%(La/Y=1/1)to 88.6%(La/Y=1/5).The hydrogen diffusion rate in the bulk of the alloy is the controlling step of hydriding/dehydriding kinetics.The Y ele ment can effectively inhibit the hydrogen-induced amorphous(HIA)of La-Y-Ni alloys,but the poor stability of the Y element in alkaline KOH aqueous solution leads to a decrease in the electrochemical cyclic stability with increasing Y content.
基金financial supported by the National Key R&D program of China(2018YFB1501602)the National Natural Science Foundation of China(22121001,22172127 and 91945301)。
文摘Selective oxidation of biomass and its derivatives to dicarboxylic acids represents a promising route for biomass valorization.However,the co-presence of multiple functional groups in biomass molecules makes the selective oxidation of particular functional a challenging task.Here,we demonstrate an efficient electrocatalytic system consisting of nickel oxide(NiO)and a nitroxyl radical,i.e.,2,2,6,6-tetrame thylpiperidine-1-oxyl(TEMPO)or 4-acetamido-TEMPO(ACT),for the selective oxidation of key bioplatform molecules including glucose,xylose and 5-hydroxymethylfurfural(HMF)into corresponding dicarboxylic acids,i.e.,glucaric acid,xylaric acid,and 2,5-furandicarboxylic acid(FDCA).NiO is clarified as the active catalyst for the oxidation of aldehyde in bio-platform molecules to carboxylic acid,while TEMPO or ACT is responsible for the oxidation of primary alcohol to aldehyde.The combination of NiO and TEMPO or ACT significantly accelerated the tandem oxidation of aldehyde and hydroxyl groups in glucose,xylose and HMF,thus achieving excellent yields(83%-99%)of dicarboxylic acids.Moreover,the combination catalyst enables the selective oxidation of glucose and xylose with high concentrations(e.g.,20 wt%),which offers a promising strategy for biomass valorization.
基金the Special Foundation for the National Science and Technology Basic Research Program of China(2021FY100303)the Guangdong Provincial Science and Technology Program(2021B1212050021,2021B1212110003)+1 种基金the GDAS Special Project of Science and Technology Development(2021GDASYL-20210103052)the Young Top-notch Talent Cultivation Program of Hubei Province and the Youth Innovation Promotion Association of the Chinese Academy of Sciences(CAS)(2019328).
文摘Coronavirus(CoV)spillover originating from game animals,particularly pangolins,is currently a significant concern.Meanwhile,vigilance is urgently needed for coronaviruses carried by bats,which are known as natural reservoirs of many coronaviruses.In this study,we collected 729 anal swabs of 20 different bat species from nine locations in Yunnan and Guangdong provinces,southern China,in 2016 and 2017,and described the molecular characteristics and genetic diversity of alphacoronaviruses(αCoVs)and betacoronaviruses(βCoVs)found in these bats.Using RT-PCR,we identified 58(8.0%)bat CoVs in nine bat species from six locations.Furthermore,using the Illumina platform,we obtained two representative full-length genomes of the bat CoVs,namely TyRo-CoV-162275 and TyRo-CoV-162269.Sequence analysis showed that TyRo-CoV-162275 shared the highest identity with Malayan pangolin(Manis javanica)HKU4-related coronaviruses(MjHKU4r-CoVs)from Guangxi Province,whereas TyRo-CoV-162269 was closely related to HKU33-CoV discovered in a greater bamboo bat(Tylonycteris robustula)from Guizhou Province.Notably,TyRo-CoV-162275 has a putative furin protease cleavage site in its S protein and is likely to utilize human dipeptidyl peptidase-4(hDPP4)as a cell-entry receptor,similar to MERSCoV.To the best of our knowledge,this is the first report of a bat HKU4r-CoV strain containing a furin protease cleavage site.These findings expand our understanding of coronavirus geographic and host distributions.
基金financed by the Environment Construction & Capacity Building of GDAS’Research Platform(2016GDASPT-0215)the Science & Technology Planning Project of Guangdong(2013B050800024 and 2015A020209093)Science & Technology Planning Project of Guangzhou(201707010128)
文摘Bats carry a variety of viruses, and some of them cause public health problems. Macao, which is famous for its gambling industry, has a complex population structure. The globalization in such an international metropolis has enhanced the chance of disease transmission. Therefore, surveillance of zoonotic viruses is necessary for the early warning of potential emerging infectious diseases.Here, we report the first surveillance of bat viruses in Macao. In this study, we collected 1004 samples involving 10 bat species from 7 sites from April 2015 to May 2016, and examined the presence of viruses using nucleic acid-based methods. Coronaviruses, adenoviruses and paramyxoviruses were detected in these samples, with a high prevalence of coronaviruses. While,none was positive for hepatitis A virus, hepatitis E virus or hantavirus. Co-infections are not common in those bat species, but coronavirus HKU6 and adenovirus can be found commonly occurred in Myotis ricketti.
基金This work was supported by the National Key Research&Development Program of China(2017YFB0202203)National Natural Science Foundation of China(61472354 and 61672452)NSFC-Guangdong Joint Fund(U1611263).
文摘In complex multivariate data sets,different features usually include diverse associations with different variables,and different variables are associated within different regions.Therefore,exploring the associations between variables and voxels locally becomes necessary to better understand the underlying phenomena.In this paper,we propose a co-analysis framework based on biclusters,which are two subsets of variables and voxels with close scalar-value relationships,to guide the process of visually exploring multivariate data.We first automatically extract all meaningful biclusters,each of which only contains voxels with a similar scalar-value pattern over a subset of variables.These biclusters are organized according to their variable sets,and biclusters in each variable set are further grouped by a similarity metric to reduce redundancy and support diversity during visual exploration.Biclusters are visually represented in coordinated views to facilitate interactive exploration of multivariate data from the similarity between biclusters and the correlation of scalar values with different variables.Experiments on several representative multivariate scientific data sets demonstrate the effectiveness of our framework in exploring local relationships among variables,biclusters and scalar values in the data.
