Nucleotide diversity (pi) and linkage disequilibrium (LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method. Japanese larch (Larix kaempferi) is an important timber c...Nucleotide diversity (pi) and linkage disequilibrium (LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method. Japanese larch (Larix kaempferi) is an important timber coniferous tree species for pulping and papermaking, but its high lignin content has significantly restricted it application potential. In this study, the LACCASE gene, that plays an important regulatory role for lignin biosynthesis, was selected as research target. The full-length cDNA and genomic sequences of the encoding LkLAC8 gene were isolated from the LACCASE expressed sequence tags of the Japanese larch transcriptome database using the rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA was determined to be 1940 bp, with an open reading frame (ORF, 1734 bp) that encoded a protein of 577 AA. This protein contains four highly specific Cu2+ binding sites and 11 glycosylation sites, thus belonging to the LACCASE family. The deduced protein sequence shared an 89% identity with the PtaLAC from Pinus taeda. A real-time PCR analysis showed that the LkLAC8 transcript was expressed predominantly in mature xylem, with moderate levels in the immature xylem, cambium and mature leaves, the lowest in the roots. Lastly, the genomic sequences of LkLAC8 in 40 individuals from six naturally distributed populations of Japanese larch were amplified, and a total of 201 SNPs (103 and 98 mutation types of transition and transversion, respectively) were detected; the frequency of the SNPs was 1/19 bp. Nucleotide diversity among the six populations ranged from 0.0034 to 0.0053, which suggested that there were no significant differences among the populations. The LD analysis showed that the LD level decayed rapidly within the increasing length of the LkLAC8 gene. These results implied that LD mapping and association analysis based on candidate gene may be feasible for the marker-assisted breeding of new germplasms with low lignin in Japanese larch.展开更多
Inkjet printing is a promising alternative for the fabrication of thin film components for solid oxide fuel cells(SOFCs) due to its contactless, mask free, and controllable printing process. In order to obtain satisfy...Inkjet printing is a promising alternative for the fabrication of thin film components for solid oxide fuel cells(SOFCs) due to its contactless, mask free, and controllable printing process. In order to obtain satisfying electrolyte thin layer structures in anode-supported SOFCs, the preparation of suitable electrolyte ceramic inks is a key. At present, such a kind of 8 mol% Y_(2)O_(3)-stabilized ZrO_(2)(8 YSZ) electrolyte ceramic ink with long-term stability and high solid loading(> 15 wt%) seems rare for precise inkjet printing, and a number of characterization and performance aspects of the inks, such as homogeneity, viscosity, and printability, should be studied. In this study, 8 YSZ ceramic inks of varied compositions were developed for inkjet printing of SOFC ceramic electrolyte layers. The dispersing effect of two types of dispersants, i.e., polyacrylic acid ammonium(PAANH4) and polyacrylic acid(PAA), were compared. The results show that ultrasonic dispersion treatment can help effectively disperse the ceramic particles in the inks. PAANH4 has a better dispersion effect for the inks developed in this study. The inks show excellent printable performance in the actual printing process. The stability of the ink can be maintained for a storage period of over 30 days with the help of initial ultrasonic dispersion. Finally, micron-size thin 8 YSZ electrolyte films were successfully fabricated through inkjet printing and sintering, based on the as-developed high solid loading 8 YSZ inks(20 wt%). The films show fully dense and intact structural morphology and smooth interfacial bonding, offering an improved structural quality of electrolyte for enhanced SOFC performance.展开更多
Three-dimensional(3D)grid porous electrodes introduce vertically aligned pores as a convenient path for the transport of lithium-ions(Li-ions),thereby reducing the total transport distance of Li-ions and improving the...Three-dimensional(3D)grid porous electrodes introduce vertically aligned pores as a convenient path for the transport of lithium-ions(Li-ions),thereby reducing the total transport distance of Li-ions and improving the reaction kinetics.Although there have been other studies focusing on 3D electrodes fabricated by 3D printing,there still exists a gap between electrode design and their electrochemical performance.In this study,we try to bridge this gap through a comprehensive investigation on the effects of various electrode parameters including the electrode porosity,active material particle diameter,electrode electronic conductivity,electrode thickness,line width,and pore size on the electrochemical performance.Both numerical simulations and experimental investigations are conducted to systematically examine these effects.3D grid porous Li_(4)Ti_(5)O_(12)(LTO)thick electrodes are fabricated by low temperature direct writing technology and the electrodes with the thickness of 1085μm and areal mass loading of 39.44 mg·cm^(−2) are obtained.The electrodes display impressive electrochemical performance with the areal capacity of 5.88 mAh·cm^(−2)@1.0 C,areal energy density of 28.95 J·cm^(−2)@1.0 C,and areal power density of 8.04 mW·cm^(−2)@1.0 C.This study can provide design guidelines for obtaining 3D grid porous electrodes with superior electrochemical performance.展开更多
Lanthanum strontium cobalt ferrite(LSCF)is an appreciable cathode material for solid oxide fuel cells(SOFCs),and it has been widely investigated,owing to its excellent thermal and chemical stability.However,its poor o...Lanthanum strontium cobalt ferrite(LSCF)is an appreciable cathode material for solid oxide fuel cells(SOFCs),and it has been widely investigated,owing to its excellent thermal and chemical stability.However,its poor oxygen reduction reaction(ORR)activity,particularly at a temperature of≤800℃,causes setbacks in achieving a peak power density of>1.0 W·cm^(-2),limiting its application in the commercialization of SOFCs.To improve the ORR of LSCF,doping strategies have been found useful.Herein,the porous tantalum-doped LSCF materials(La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)7Ta_(0.03)O_(3)(LSCFT-0),La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)4Ta0.06O_(3),and La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)Ta0.1O_(3))are prepared via camphor-assisted solid-state reaction(CSSR).The LSCFT-0 material exhibits promising ORR with area-specific resistance(ASR)of 1.260,_(0.5)80,0.260,0.100,and 0.06Ω·cm^(2)at 600,650,700,750,and 800℃,respectively.The performance is about 2 times higher than that of undoped La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.6)O_(3)with the ASR of 2.515,1.191,_(0.5)96,0.320,and 0.181Ω·cm^(2)from the lowest to the highest temperature.Through material characterization,it was found that the incorporated Ta occupied the B-site of the material,leading to the enhancement of the ORR activity.With the use of LSCFT-0 as the cathode material for anode-supported single-cell,the power density of>1.0 W·cm^(-2)was obtained at a temperature<800℃.The results indicate that the CSSR-derived LSCFT is a promising cathode material for SOFCs.展开更多
The tradeoff between energy and power densities is a critical challenge for commercial tape-cast lithium-ion batteries(LIBs).In this study,three-dimensional(3D)LIBs with interdigitated electrode structures are designe...The tradeoff between energy and power densities is a critical challenge for commercial tape-cast lithium-ion batteries(LIBs).In this study,three-dimensional(3D)LIBs with interdigitated electrode structures are designed and fabricated via 3D printing to overcome this tradeoff.The evolution of battery design from tape-cast thin planar electrodes to interdigitated 3D electrodes is discussed.Numerical simulations based on COMSOL Multiphysics are performed to elucidate the advantages of interdigitated battery design.Interdigitated LIBs composed of comb-like 3D high-voltage LiCoO2(HV-LCO)cathodes and comb-like 3D natural graphite anodes are fabricated via 3D printing.Additionally,printable HV-LCO inks with appropriate rheological properties are developed for 3D printing.HV-LCO half-cells with Li foil as the counter electrode and an interdigitated full battery with NG anodes as the counter electrode are assembled to test the electrochemical performance.The results show that interdigitated full batteries fabricated via 3D printing offer high specific capacities and stable cycling performance.Full batteries with an electrode thickness of 882µm can achieve a high areal capacity of 5.88 mAh·cm−2@0.1 C,an areal energy density of 41.4 J·cm−2,and an areal power density of 41.0 mW·cm−2@1.0 C,which are approximately 10 times the values afforded by conventional tape-cast thin batteries.展开更多
基金financially supported by the Fundamental Research Funds for the Central Non-profit Research Institution of CAF(RIF2014-06)the Forestry Industry Research special funds for Public Welfare Projects(201504104)
文摘Nucleotide diversity (pi) and linkage disequilibrium (LD) analysis based on SNP marker could provide a sound basis for choosing an association analysis method. Japanese larch (Larix kaempferi) is an important timber coniferous tree species for pulping and papermaking, but its high lignin content has significantly restricted it application potential. In this study, the LACCASE gene, that plays an important regulatory role for lignin biosynthesis, was selected as research target. The full-length cDNA and genomic sequences of the encoding LkLAC8 gene were isolated from the LACCASE expressed sequence tags of the Japanese larch transcriptome database using the rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA was determined to be 1940 bp, with an open reading frame (ORF, 1734 bp) that encoded a protein of 577 AA. This protein contains four highly specific Cu2+ binding sites and 11 glycosylation sites, thus belonging to the LACCASE family. The deduced protein sequence shared an 89% identity with the PtaLAC from Pinus taeda. A real-time PCR analysis showed that the LkLAC8 transcript was expressed predominantly in mature xylem, with moderate levels in the immature xylem, cambium and mature leaves, the lowest in the roots. Lastly, the genomic sequences of LkLAC8 in 40 individuals from six naturally distributed populations of Japanese larch were amplified, and a total of 201 SNPs (103 and 98 mutation types of transition and transversion, respectively) were detected; the frequency of the SNPs was 1/19 bp. Nucleotide diversity among the six populations ranged from 0.0034 to 0.0053, which suggested that there were no significant differences among the populations. The LD analysis showed that the LD level decayed rapidly within the increasing length of the LkLAC8 gene. These results implied that LD mapping and association analysis based on candidate gene may be feasible for the marker-assisted breeding of new germplasms with low lignin in Japanese larch.
基金supported by the National Natural Science Foundation of China (51975384)Guangdong Basic and Applied Basic Research Foundation (2020A1515011547)+1 种基金Natural Science Foundation of Shenzhen (JCYJ20190808144009478)Key-Area Research and Development Program of Guangdong Province (2020B090924003)。
文摘Inkjet printing is a promising alternative for the fabrication of thin film components for solid oxide fuel cells(SOFCs) due to its contactless, mask free, and controllable printing process. In order to obtain satisfying electrolyte thin layer structures in anode-supported SOFCs, the preparation of suitable electrolyte ceramic inks is a key. At present, such a kind of 8 mol% Y_(2)O_(3)-stabilized ZrO_(2)(8 YSZ) electrolyte ceramic ink with long-term stability and high solid loading(> 15 wt%) seems rare for precise inkjet printing, and a number of characterization and performance aspects of the inks, such as homogeneity, viscosity, and printability, should be studied. In this study, 8 YSZ ceramic inks of varied compositions were developed for inkjet printing of SOFC ceramic electrolyte layers. The dispersing effect of two types of dispersants, i.e., polyacrylic acid ammonium(PAANH4) and polyacrylic acid(PAA), were compared. The results show that ultrasonic dispersion treatment can help effectively disperse the ceramic particles in the inks. PAANH4 has a better dispersion effect for the inks developed in this study. The inks show excellent printable performance in the actual printing process. The stability of the ink can be maintained for a storage period of over 30 days with the help of initial ultrasonic dispersion. Finally, micron-size thin 8 YSZ electrolyte films were successfully fabricated through inkjet printing and sintering, based on the as-developed high solid loading 8 YSZ inks(20 wt%). The films show fully dense and intact structural morphology and smooth interfacial bonding, offering an improved structural quality of electrolyte for enhanced SOFC performance.
基金This work is supported by the National Natural Science Foundation of China(Nos.51705334 and 51975384)the Shenzhen Science&Technology Projects(Nos.JCYJ20180305125025855 and JCYJ20200109105618137).
文摘Three-dimensional(3D)grid porous electrodes introduce vertically aligned pores as a convenient path for the transport of lithium-ions(Li-ions),thereby reducing the total transport distance of Li-ions and improving the reaction kinetics.Although there have been other studies focusing on 3D electrodes fabricated by 3D printing,there still exists a gap between electrode design and their electrochemical performance.In this study,we try to bridge this gap through a comprehensive investigation on the effects of various electrode parameters including the electrode porosity,active material particle diameter,electrode electronic conductivity,electrode thickness,line width,and pore size on the electrochemical performance.Both numerical simulations and experimental investigations are conducted to systematically examine these effects.3D grid porous Li_(4)Ti_(5)O_(12)(LTO)thick electrodes are fabricated by low temperature direct writing technology and the electrodes with the thickness of 1085μm and areal mass loading of 39.44 mg·cm^(−2) are obtained.The electrodes display impressive electrochemical performance with the areal capacity of 5.88 mAh·cm^(−2)@1.0 C,areal energy density of 28.95 J·cm^(−2)@1.0 C,and areal power density of 8.04 mW·cm^(−2)@1.0 C.This study can provide design guidelines for obtaining 3D grid porous electrodes with superior electrochemical performance.
基金This work is supported by the National Natural Science Foundation of China(No.51975384)Guangdong Basic and Applied Basic Research Foundation(No.2020A1515011547)Shenzhen Fundamental Research Project(Nos.JCYJ20190808144009478,20200731211324001).
文摘Lanthanum strontium cobalt ferrite(LSCF)is an appreciable cathode material for solid oxide fuel cells(SOFCs),and it has been widely investigated,owing to its excellent thermal and chemical stability.However,its poor oxygen reduction reaction(ORR)activity,particularly at a temperature of≤800℃,causes setbacks in achieving a peak power density of>1.0 W·cm^(-2),limiting its application in the commercialization of SOFCs.To improve the ORR of LSCF,doping strategies have been found useful.Herein,the porous tantalum-doped LSCF materials(La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)7Ta_(0.03)O_(3)(LSCFT-0),La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)4Ta0.06O_(3),and La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.5)Ta0.1O_(3))are prepared via camphor-assisted solid-state reaction(CSSR).The LSCFT-0 material exhibits promising ORR with area-specific resistance(ASR)of 1.260,_(0.5)80,0.260,0.100,and 0.06Ω·cm^(2)at 600,650,700,750,and 800℃,respectively.The performance is about 2 times higher than that of undoped La_(0.6)Sr_(0.4)Co_(0.4)Fe_(0.6)O_(3)with the ASR of 2.515,1.191,_(0.5)96,0.320,and 0.181Ω·cm^(2)from the lowest to the highest temperature.Through material characterization,it was found that the incorporated Ta occupied the B-site of the material,leading to the enhancement of the ORR activity.With the use of LSCFT-0 as the cathode material for anode-supported single-cell,the power density of>1.0 W·cm^(-2)was obtained at a temperature<800℃.The results indicate that the CSSR-derived LSCFT is a promising cathode material for SOFCs.
基金Shenzhen Municipal Science&Technology Projects of China(Grant Nos.JCYJ20200109105618137,GJHZ20200731095805016).
文摘The tradeoff between energy and power densities is a critical challenge for commercial tape-cast lithium-ion batteries(LIBs).In this study,three-dimensional(3D)LIBs with interdigitated electrode structures are designed and fabricated via 3D printing to overcome this tradeoff.The evolution of battery design from tape-cast thin planar electrodes to interdigitated 3D electrodes is discussed.Numerical simulations based on COMSOL Multiphysics are performed to elucidate the advantages of interdigitated battery design.Interdigitated LIBs composed of comb-like 3D high-voltage LiCoO2(HV-LCO)cathodes and comb-like 3D natural graphite anodes are fabricated via 3D printing.Additionally,printable HV-LCO inks with appropriate rheological properties are developed for 3D printing.HV-LCO half-cells with Li foil as the counter electrode and an interdigitated full battery with NG anodes as the counter electrode are assembled to test the electrochemical performance.The results show that interdigitated full batteries fabricated via 3D printing offer high specific capacities and stable cycling performance.Full batteries with an electrode thickness of 882µm can achieve a high areal capacity of 5.88 mAh·cm−2@0.1 C,an areal energy density of 41.4 J·cm−2,and an areal power density of 41.0 mW·cm−2@1.0 C,which are approximately 10 times the values afforded by conventional tape-cast thin batteries.
