Forward radiative transfer(RT)models are essential for atmospheric applications such as remote sensing and weather and climate models,where computational efficiency becomes equally as important as accuracy for high-re...Forward radiative transfer(RT)models are essential for atmospheric applications such as remote sensing and weather and climate models,where computational efficiency becomes equally as important as accuracy for high-resolution hyperspectral measurements that need rigorous RT simulations for thousands of channels.This study introduces a fast and accurate RT model for the hyperspectral infrared(HIR)sounder based on principal component analysis(PCA)or machine learning(i.e.,neural network,NN).The Geosynchronous Interferometric Infrared Sounder(GIIRS),the first HIR sounder onboard the geostationary Fengyun-4 satellites,is considered to be a candidate example for model development and validation.Our method uses either PCA or NN(PCA/NN)twice for the atmospheric transmittance and radiance,respectively,to reduce the number of independent but similar simulations to accelerate RT simulations;thereby,it is referred to as a multi-domain compression model.The first PCA/NN gives monochromatic gas transmittance in both spectral and atmospheric pressure domains for each gas independently.The second PCA/NN is performed in the traditional spectral radiance domain.Meanwhile,a new method is introduced to choose representative variables for the PCA/NN scheme developments.The model is three orders of magnitude faster than the standard line-by-line-based simulations with averaged brightness temperature difference(BTD)less than 0.1 K,and the compressions based on PCA or NN methods result in comparable efficiency and accuracy.Our fast model not only avoids an excessively complicated transmittance scheme by using PCA/NN but is also highly flexible for hyperspectral instruments with similar spectral ranges simply by updating the corresponding spectral response functions.展开更多
Investigation of metal–organic frameworks(MOFs)for biomedical applications has attracted much attention in recent years.MOFs are regarded as a promising class of nanocarriers for drug delivery owing to well-defined s...Investigation of metal–organic frameworks(MOFs)for biomedical applications has attracted much attention in recent years.MOFs are regarded as a promising class of nanocarriers for drug delivery owing to well-defined structure,ultrahigh surface area and porosity,tunable pore size,and easy chemical functionalization.In this review,the unique properties of MOFs and their advantages as nanocarriers for drug delivery in biomedical applications were discussed in the first section.Then,state-ofthe-art strategies to functionalize MOFs with therapeutic agents were summarized,including surface adsorption,pore encapsulation,covalent binding,and functional molecules as building blocks.In the third section,the most recent biological applications of MOFs for intracellular delivery of drugs,proteins,and nucleic acids,especially aptamers,were presented.Finally,challenges and prospects were comprehensively discussed to provide context for future development of MOFs as efficient drug delivery systems.展开更多
Copper(Cu)-based materials(such as cuprates,Cu chalcogenides,and Cu halides)often exhibit unusual properties such as superconductivity,ultralow thermal conductivity,and superionicity.However,the electronic origin of t...Copper(Cu)-based materials(such as cuprates,Cu chalcogenides,and Cu halides)often exhibit unusual properties such as superconductivity,ultralow thermal conductivity,and superionicity.However,the electronic origin of these unusual behaviors remains elusive.In this study,we demonstrate that the high-lying occupied 3d orbital of Cu causes a strong s-d coupling with its unoccupied 4s state when local symmetry is reduced.This leads to strong phonon anharmonicity and is responsible for these intriguing properties.For example,during thermal transport,symmetry-controlled s-d coupling can substantially lower the lattice potential barrier,thereby enhancing the anharmonicity and scattering between phonons and ultimately significantly reducing lattice thermal conductivity.We confirmed this understanding with Raman spectra measurements,which demonstrated a remarkable red shift in the phonon vibrational frequency with an increase in the temperature of Cu-based semiconductors.Our study shows that the cause of phonon anharmonicity is related to the fundamental electronic structures,which can also explain other unusual physical properties of the Cu compounds.展开更多
Pesticides refer to the chemicals to regulate plant growth and control pests used in agriculture.However,the extensive use of pesticides causes serious pollution that threatens the ecological environment and human hea...Pesticides refer to the chemicals to regulate plant growth and control pests used in agriculture.However,the extensive use of pesticides causes serious pollution that threatens the ecological environment and human health.Photocatalytic degradation of pesticides has become a promising way to deal with pesticide pollution.In this review,pesticides are classified according to the different targets and chemical structures.The recent developments on semiconductor-based photocatalysts including metal oxides,metal oxyhalides,carbon nitrides,metal sulfides were reviewed for degradation of pesticides.Importantly,several modification strategies to improve the photocatalytic performance are described such as doping,heterojunction construction,defect engineering,with special emphasis on anchoring single atom catalyst.Moreover,extensive efforts should be made to indepth understand the photodegradation mechanism by monitoring key intermediates.Our perspectives on the key challenges and future directions of developing high-performance semiconductor-based photocatalysts for pesticide degradation are elaborated.展开更多
Our previous work reported a relationship between FOXO1 mutations and growth of Qinchuan(QC) cattle. Here, we performed differential expression analysis of FOXO1 and its association analysis with growth traits in QC c...Our previous work reported a relationship between FOXO1 mutations and growth of Qinchuan(QC) cattle. Here, we performed differential expression analysis of FOXO1 and its association analysis with growth traits in QC cattle. First, we measured the expression of the FOXO1 gene in nine tissues during three developmental stages. The results showed that FOXO1 was abundantly expressed in tissues of calves but was strongly repressed in adulthood, although there was significant transcription in skeletal muscle. FOXO1 expression showed gradual up-regulation during differentiation of primary bovine skeletal muscle cells.We also identified six SNPs of the bovine FOXO1 gene by sequencing DNA pools of samples from 488 individuals, and association analysis indicated that five SNPs were significantly associated with some growth traits in the QC population. We further analyzed four haplotype combinations of the six SNPs and found significant correlation with body length(P<0.01). In conclusion, FOXO1 participates in bovine myocyte differentiation and expression, and may be a strong candidate as a gene that affects growth traits that could be exploited in a QC cattle breeding program. More generally, our data provide a new theoretical basis for QC beef breeding and beef quality improvement.展开更多
Electrocatalytic water splitting into hydrogen is one of the most favorable approaches to produce renewable energy.MoS_(2)has received great research attention for both hydrogen evolution reaction(HER)and oxygen evolu...Electrocatalytic water splitting into hydrogen is one of the most favorable approaches to produce renewable energy.MoS_(2)has received great research attention for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)due to its unique structure and ability to be chemically modified,enabling its electrocatalytic activity to be further enhanced or made comparable to that of Pt-based materials.In this review,we discuss the important fabrication approaches of MoS_(2)ultrathin nanosheet(MoS_(2)NS)to improve the intrinsic catalytic activity of bulk MoS_(2).Moreover,several modification strategies involve either morphology modulation or electron structural modulation to improve the charge transfer kinetics,including doping,vacancy,and heterojunction construction or single-atom anchor.Our perspectives on the key challenges and future directions of developing high-performance MoS_(2)-based electrocatalysts for overall water splitting are also discussed.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.42122038)。
文摘Forward radiative transfer(RT)models are essential for atmospheric applications such as remote sensing and weather and climate models,where computational efficiency becomes equally as important as accuracy for high-resolution hyperspectral measurements that need rigorous RT simulations for thousands of channels.This study introduces a fast and accurate RT model for the hyperspectral infrared(HIR)sounder based on principal component analysis(PCA)or machine learning(i.e.,neural network,NN).The Geosynchronous Interferometric Infrared Sounder(GIIRS),the first HIR sounder onboard the geostationary Fengyun-4 satellites,is considered to be a candidate example for model development and validation.Our method uses either PCA or NN(PCA/NN)twice for the atmospheric transmittance and radiance,respectively,to reduce the number of independent but similar simulations to accelerate RT simulations;thereby,it is referred to as a multi-domain compression model.The first PCA/NN gives monochromatic gas transmittance in both spectral and atmospheric pressure domains for each gas independently.The second PCA/NN is performed in the traditional spectral radiance domain.Meanwhile,a new method is introduced to choose representative variables for the PCA/NN scheme developments.The model is three orders of magnitude faster than the standard line-by-line-based simulations with averaged brightness temperature difference(BTD)less than 0.1 K,and the compressions based on PCA or NN methods result in comparable efficiency and accuracy.Our fast model not only avoids an excessively complicated transmittance scheme by using PCA/NN but is also highly flexible for hyperspectral instruments with similar spectral ranges simply by updating the corresponding spectral response functions.
基金supported by the National Natural Science Foundation of China(Grant No.21827811)Research and development plan of key areas in Hunan Province(Grant No.2019SK2201)Innovation science and technology plan of Hunan Province(Grant No.2017XK2103).
文摘Investigation of metal–organic frameworks(MOFs)for biomedical applications has attracted much attention in recent years.MOFs are regarded as a promising class of nanocarriers for drug delivery owing to well-defined structure,ultrahigh surface area and porosity,tunable pore size,and easy chemical functionalization.In this review,the unique properties of MOFs and their advantages as nanocarriers for drug delivery in biomedical applications were discussed in the first section.Then,state-ofthe-art strategies to functionalize MOFs with therapeutic agents were summarized,including surface adsorption,pore encapsulation,covalent binding,and functional molecules as building blocks.In the third section,the most recent biological applications of MOFs for intracellular delivery of drugs,proteins,and nucleic acids,especially aptamers,were presented.Finally,challenges and prospects were comprehensively discussed to provide context for future development of MOFs as efficient drug delivery systems.
基金supported by the National Natural Science Foundation of China(Grant Nos.12174099,61922077,11874347,12088101,11991060U2230402)+3 种基金the National Key Research and Development Program of China(Grant Nos.2018YFB2200100,and 2020YFB1506400)the Key Research Program of the Chinese Academy of Sciences(Grant No.XDPB22)the Beijing Science and Technology Committee(Grant No.Z181100005118003)supported by the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.Y2021042)。
文摘Copper(Cu)-based materials(such as cuprates,Cu chalcogenides,and Cu halides)often exhibit unusual properties such as superconductivity,ultralow thermal conductivity,and superionicity.However,the electronic origin of these unusual behaviors remains elusive.In this study,we demonstrate that the high-lying occupied 3d orbital of Cu causes a strong s-d coupling with its unoccupied 4s state when local symmetry is reduced.This leads to strong phonon anharmonicity and is responsible for these intriguing properties.For example,during thermal transport,symmetry-controlled s-d coupling can substantially lower the lattice potential barrier,thereby enhancing the anharmonicity and scattering between phonons and ultimately significantly reducing lattice thermal conductivity.We confirmed this understanding with Raman spectra measurements,which demonstrated a remarkable red shift in the phonon vibrational frequency with an increase in the temperature of Cu-based semiconductors.Our study shows that the cause of phonon anharmonicity is related to the fundamental electronic structures,which can also explain other unusual physical properties of the Cu compounds.
基金the National Natural Science Foundation of China(Nos.21902157 and 51702004)Starting Fund for Scientific Research of High-Level Talents,Anhui Agricultural University(No.rc382108)+5 种基金the Open Fund of the State Key Laboratory of Catalysis in Dalian Institute of Chemical Physics,Chinese Academy of Sciences(DICP,CAS)(No.N-21-12)the Open Fund of the State Key Laboratory of Molecular Reaction Dynamics in DICP,CAS(No.SKLMRD-K202223)Key Research and Development Plan of Anhui Province(No.2022e07020037)Health Research Project of Anhui Province(No.AHWJ2022b014)Shen-Nong Scholar Program of Anhui Agricultural University(No.rc382101)Innovation and Entrepreneurship Plan for College Students(Nos.X202210364252,X202210364274,and X202210364532).
文摘Pesticides refer to the chemicals to regulate plant growth and control pests used in agriculture.However,the extensive use of pesticides causes serious pollution that threatens the ecological environment and human health.Photocatalytic degradation of pesticides has become a promising way to deal with pesticide pollution.In this review,pesticides are classified according to the different targets and chemical structures.The recent developments on semiconductor-based photocatalysts including metal oxides,metal oxyhalides,carbon nitrides,metal sulfides were reviewed for degradation of pesticides.Importantly,several modification strategies to improve the photocatalytic performance are described such as doping,heterojunction construction,defect engineering,with special emphasis on anchoring single atom catalyst.Moreover,extensive efforts should be made to indepth understand the photodegradation mechanism by monitoring key intermediates.Our perspectives on the key challenges and future directions of developing high-performance semiconductor-based photocatalysts for pesticide degradation are elaborated.
基金supported by the National Natural Science Foundation of China (31272408)Agricultural Science and Technology Innovation Projects of Shaanxi Province (2012NKC01-13)+1 种基金Program of National Beef Cattle Industrial Technology System (CARS-38)National High Technology Research and Development Program of China (2013AA102505)
文摘Our previous work reported a relationship between FOXO1 mutations and growth of Qinchuan(QC) cattle. Here, we performed differential expression analysis of FOXO1 and its association analysis with growth traits in QC cattle. First, we measured the expression of the FOXO1 gene in nine tissues during three developmental stages. The results showed that FOXO1 was abundantly expressed in tissues of calves but was strongly repressed in adulthood, although there was significant transcription in skeletal muscle. FOXO1 expression showed gradual up-regulation during differentiation of primary bovine skeletal muscle cells.We also identified six SNPs of the bovine FOXO1 gene by sequencing DNA pools of samples from 488 individuals, and association analysis indicated that five SNPs were significantly associated with some growth traits in the QC population. We further analyzed four haplotype combinations of the six SNPs and found significant correlation with body length(P<0.01). In conclusion, FOXO1 participates in bovine myocyte differentiation and expression, and may be a strong candidate as a gene that affects growth traits that could be exploited in a QC cattle breeding program. More generally, our data provide a new theoretical basis for QC beef breeding and beef quality improvement.
基金the National Natural Science Foundation of China(No.21902157)Starting fund for scientific research of high-level talents,Anhui Agricultural University(No.rc382108)+1 种基金the Open Fund of The State Key Laboratory of Catalysis in DICP,CAS(N-21-12)the Open Fund of The State Key Laboratory of Molecular Reaction Dynamics in DICP,CAS(SKLMRDK202223).
文摘Electrocatalytic water splitting into hydrogen is one of the most favorable approaches to produce renewable energy.MoS_(2)has received great research attention for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)due to its unique structure and ability to be chemically modified,enabling its electrocatalytic activity to be further enhanced or made comparable to that of Pt-based materials.In this review,we discuss the important fabrication approaches of MoS_(2)ultrathin nanosheet(MoS_(2)NS)to improve the intrinsic catalytic activity of bulk MoS_(2).Moreover,several modification strategies involve either morphology modulation or electron structural modulation to improve the charge transfer kinetics,including doping,vacancy,and heterojunction construction or single-atom anchor.Our perspectives on the key challenges and future directions of developing high-performance MoS_(2)-based electrocatalysts for overall water splitting are also discussed.
