The electronic structures of PF and PF＋ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, a...The electronic structures of PF and PF＋ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, and the Davidson correction（q-Q） are also considered. The spectroscopic parameters of bound states are derived by the electronic structures of PF and PF＋, which are in good accordance with the measurements. The transition dipole moments of spin-allowed transitions are evaluated, and the radiative lifetimes of several A S states of PF and PF＋ are obtained.展开更多
Precise information about the spatial variability of soil properties is essential in developing site-specific soil management, such as variable rate application of fertilizers. In this study the sampling grid of 100 m...Precise information about the spatial variability of soil properties is essential in developing site-specific soil management, such as variable rate application of fertilizers. In this study the sampling grid of 100 m × 100 m was established to collect 1 703 soil samples at the depth of 0-20 cm, and examine spatial patterns including 13 soil chemical properties （pH, OM, NH4^＋, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn） in a 1 760 ha rice field in Haifeng farm, China, from 6th to 22nd of April, 2006, before fertilizer application and planting. Soil analysis was performed by ASI （Agro Services International） and data were analyzed both statistically and geostatistically. Results showed that the contents of soil OM, NH4^＋, and Zn in Haifeng farm were very low for rice production and those of others were enough to meet the need for rice cultivation. The spatial distribution model and spatial dependence level for 13 soil chemical properties varied in the field. Soil Mg and B showed strong spatial variability on both descriptive statistics and geostatistics, and other properties showed moderate spatial variability. The maximum ranges for K, Ca, Mg, S, Cu and Mn were all - 3 990.6 m and the minimum ranges for soil pH, OM, NH4^＋, P, Fe, and Zn ranged from 516.7 to 1 166.2 m. Clear patchy distribution of N, P, K, Mg, S, B, Mn, and Zn were found from their spatial distribution maps. This proved that sampling strategy for estimating variability should be adapted to the different soil chemical properties and field management. Therefore, the spatial variability of soil chemical properties with strong spatial dependence could be readily managed and a site-specific fertilization scheme for precision farming could be easily developed.展开更多
Organic fluorophores with dynamic conformations in the excited state have played a significant role in applications of organic functional dyes.Among them,dihydrophenazine-based dynamic fluorophores involving a photoin...Organic fluorophores with dynamic conformations in the excited state have played a significant role in applications of organic functional dyes.Among them,dihydrophenazine-based dynamic fluorophores involving a photoinduced structural planarization process in the excited state exhibited large Stokes shifts and conformation-dependent multicolor emissions.With the developments of synthetic strategies,precise modifications on dihydrophenazinebased scaffolds have successfully afforded a variety of precise molecular structures of varying sizes and compositions,which have delicately modulated their photophysical properties.Herein,this Perspective summarizes the precise modulations of dihydrophenazine-based dynamic fluorophores,including the development of the synthetic methodologies,and tailor-made molecular models to reveal the luminescence−structure relationships.展开更多
Metal nanoclusters(NCs)are ultrasmall molecular aggregates consisting of dozens to hundreds of metal atoms consolidated by organic ligands,which represent an emerging area of nanoscience.Amide a myriad of metal NCs,co...Metal nanoclusters(NCs)are ultrasmall molecular aggregates consisting of dozens to hundreds of metal atoms consolidated by organic ligands,which represent an emerging area of nanoscience.Amide a myriad of metal NCs,copper NCs(CuNCs)comprise a low-cost,high-value subclass that has attracted great attention.The variable copper cores and diversity of protecting ligands have rendered CuNCs interesting molecular aggregates featuring structural and compositional versatility,hence showing distinctive properties and potential applications.In the present review,we have summarized the progress on atomically precise CuNCs that exhibit a range of appealing properties and applications in different fields.This review is expected to provide not only an overview of the current development on atomically precise CuNCs,but also possible directions for the future design of novel CuNCs for fundamental studies and practical applications.展开更多
Thiolate(SR)-protected gold nanoclusters(Aun(SR)m NCs)are a rare type of material capable of simultaneously exhibiting multiple physicochemical properties well-suited to specific applications,including photoluminescen...Thiolate(SR)-protected gold nanoclusters(Aun(SR)m NCs)are a rare type of material capable of simultaneously exhibiting multiple physicochemical properties well-suited to specific applications,including photoluminescence,thermocatalysis,electrocatalysis,photocatalysis,magnetism,and optical activity.Over the past several decades,there has been tremendous progress in our understanding of the structure and physicochemical properties of Aun(SR)m NCs,resulting in the ability to fine-tune the characteristics of these materials.It is therefore helpful to examine the extent to which the properties of Aun(SR)m and related metal NCs can now be adjusted based on design.This review presents representative examples of previous studies concerning the geometry,electronic structure,luminescence properties,catalysis,magnetism and optical activity of Aun(SR)m and related metal NCs and discusses the current status of the designability of these NCs to impart specific structural and physicochemical characteristics.This information is expected to accelerate the fabrication of highly functional materials based on Aun(SR)m and related metal NCs.展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11404180the Natural Science Foundation of Heilongjiang Province under Grant Nos F201335,A2015010,and A2015011the Postdoctoral Scientific Research Developmental Fund of Heilongjiang Province under Grant No LBH-Q14159
文摘The electronic structures of PF and PF＋ are calculated with the high-level configuration interaction method. To improve the precision of calculations, the spin-orbit coupling effect, the scalar relativistic effect, and the Davidson correction（q-Q） are also considered. The spectroscopic parameters of bound states are derived by the electronic structures of PF and PF＋, which are in good accordance with the measurements. The transition dipole moments of spin-allowed transitions are evaluated, and the radiative lifetimes of several A S states of PF and PF＋ are obtained.
基金funded by thestarting project of scientific research for high-level tal-ents introduced by North China University of Water Conservancy and Electric Power (200723)Shang-hai Municipal Key Task Projects of Prospering Agri-culture by the Science and Technology Plan, China(NGZ 1-10)
文摘Precise information about the spatial variability of soil properties is essential in developing site-specific soil management, such as variable rate application of fertilizers. In this study the sampling grid of 100 m × 100 m was established to collect 1 703 soil samples at the depth of 0-20 cm, and examine spatial patterns including 13 soil chemical properties （pH, OM, NH4^＋, P, K, Ca, Mg, S, B, Cu, Fe, Mn, and Zn） in a 1 760 ha rice field in Haifeng farm, China, from 6th to 22nd of April, 2006, before fertilizer application and planting. Soil analysis was performed by ASI （Agro Services International） and data were analyzed both statistically and geostatistically. Results showed that the contents of soil OM, NH4^＋, and Zn in Haifeng farm were very low for rice production and those of others were enough to meet the need for rice cultivation. The spatial distribution model and spatial dependence level for 13 soil chemical properties varied in the field. Soil Mg and B showed strong spatial variability on both descriptive statistics and geostatistics, and other properties showed moderate spatial variability. The maximum ranges for K, Ca, Mg, S, Cu and Mn were all - 3 990.6 m and the minimum ranges for soil pH, OM, NH4^＋, P, Fe, and Zn ranged from 516.7 to 1 166.2 m. Clear patchy distribution of N, P, K, Mg, S, B, Mn, and Zn were found from their spatial distribution maps. This proved that sampling strategy for estimating variability should be adapted to the different soil chemical properties and field management. Therefore, the spatial variability of soil chemical properties with strong spatial dependence could be readily managed and a site-specific fertilization scheme for precision farming could be easily developed.
基金financially supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.21790361 and 21871084)Shanghai Municipal Science and Technology Major Project(Grant No.2018SHZDZX03)+3 种基金the Fundamental Research Funds for the Central Universities,the Programme of Introducing Talents of Discipline to Universities(Grant No.B16017)Program of Shanghai Academic/Technology Research Leader(19XD1421100)the Shanghai Science and Technology Committee(Grant No.17520750100)the China Postdoctoral Science Foundation(2020M671018).
文摘Organic fluorophores with dynamic conformations in the excited state have played a significant role in applications of organic functional dyes.Among them,dihydrophenazine-based dynamic fluorophores involving a photoinduced structural planarization process in the excited state exhibited large Stokes shifts and conformation-dependent multicolor emissions.With the developments of synthetic strategies,precise modifications on dihydrophenazinebased scaffolds have successfully afforded a variety of precise molecular structures of varying sizes and compositions,which have delicately modulated their photophysical properties.Herein,this Perspective summarizes the precise modulations of dihydrophenazine-based dynamic fluorophores,including the development of the synthetic methodologies,and tailor-made molecular models to reveal the luminescence−structure relationships.
基金Science,Technology and Innovation Committee of Shenzhen Municipality,Grant/Award Number:JCYJ20180507183413211RGC Senior Research Fellowship Scheme,Grant/Award Number:SRFS2021-5S01+4 种基金Hong Kong Research Grants Council,Grant/Award Number:PolyU153062/18PGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials,Grant/Award Number:2019B121205002Hong Kong Polytechnic University,Grant/Award Number:1-ZE1CResearch Institute for Smart Energy,Grant/Award Number:CDAQMiss Clarea Au for the Endowed Professorship in Energy,Grant/Award Number:847S。
文摘Metal nanoclusters(NCs)are ultrasmall molecular aggregates consisting of dozens to hundreds of metal atoms consolidated by organic ligands,which represent an emerging area of nanoscience.Amide a myriad of metal NCs,copper NCs(CuNCs)comprise a low-cost,high-value subclass that has attracted great attention.The variable copper cores and diversity of protecting ligands have rendered CuNCs interesting molecular aggregates featuring structural and compositional versatility,hence showing distinctive properties and potential applications.In the present review,we have summarized the progress on atomically precise CuNCs that exhibit a range of appealing properties and applications in different fields.This review is expected to provide not only an overview of the current development on atomically precise CuNCs,but also possible directions for the future design of novel CuNCs for fundamental studies and practical applications.
基金Japan Society for the Promotion of Science,Grant/Award Numbers:20H02698,20H02552,18H05178,20H05115Hydrogenomics,Grant/Award Number:21H00027+7 种基金Aquatic Functional Materials,Grant/Award Numbers:18H05178,22H04562Yazaki Memorial Foundation for Science and TechnologyOgasawara Foundation for the Promotion of Science and EngineeringKao Foundation for Arts and SciencesTEPCO Memorial FoundationJapan Science SocietyTakahashi Industrial and Economic Research FoundationKubota Corporation。
文摘Thiolate(SR)-protected gold nanoclusters(Aun(SR)m NCs)are a rare type of material capable of simultaneously exhibiting multiple physicochemical properties well-suited to specific applications,including photoluminescence,thermocatalysis,electrocatalysis,photocatalysis,magnetism,and optical activity.Over the past several decades,there has been tremendous progress in our understanding of the structure and physicochemical properties of Aun(SR)m NCs,resulting in the ability to fine-tune the characteristics of these materials.It is therefore helpful to examine the extent to which the properties of Aun(SR)m and related metal NCs can now be adjusted based on design.This review presents representative examples of previous studies concerning the geometry,electronic structure,luminescence properties,catalysis,magnetism and optical activity of Aun(SR)m and related metal NCs and discusses the current status of the designability of these NCs to impart specific structural and physicochemical characteristics.This information is expected to accelerate the fabrication of highly functional materials based on Aun(SR)m and related metal NCs.
