Examples of photoluminescence(PL)are being reported with increasing frequency in a wide range of organisms from diverse ecosystems.However,the chemical basis of this PL remains poorly defined,and our understanding of i...Examples of photoluminescence(PL)are being reported with increasing frequency in a wide range of organisms from diverse ecosystems.However,the chemical basis of this PL remains poorly defined,and our understanding of its potential ecological function is still superficial.Among mammals,recent analyses have identified free-base por-phyrins as the compounds responsible for the reddish ultraviolet-induced photoluminescence(UV-PL)observed in the pelage of springhares and hedgehogs.However,the localization of the pigments within the hair largely remains to be determined.Here,we use photoluminescence multispectral imaging emission and excitation spec-troscopy to detect,map,and characterize porphyrinic compounds in skin appendages in situ.We also document new cases of mammalian UV-PL caused by free-base porphyrins in distantly related species.Spatial distribution of the UV-PL is strongly suggestive of an endogenous origin of the porphyrinic compounds.We argue that reddish UV-PL is predominantly observed in crepuscular and nocturnal mammals because porphyrins are photodegradable.Con-sequently,this phenomenon may not have a specific function in intra-or interspecific communication but rather represents a byproduct of potentially widespread physiological processes.展开更多
In this study,an extend application was developed to in situ analyze the herbal pieces of Aconitum plants by Direct Analysis in Real Time Mass Spectrometry(DART-MS).Nearly all aconitine-type alkaloids can be desorbed ...In this study,an extend application was developed to in situ analyze the herbal pieces of Aconitum plants by Direct Analysis in Real Time Mass Spectrometry(DART-MS).Nearly all aconitine-type alkaloids can be desorbed and ionized in this method,including diester diterpenoid aconitines(DDAs),monoester diterpenoid aconitines(MDAs)and some other diterpenoid aconitines.The spectra of in situ analysis for the herbal pieces of aconitum plants are similar with that of their extracts.Radix Aconiti and Radix Aconiti Kusnezoffii can be distinguished from each other by the intensity differences of character fragment ions from MDAs,such as m/z 586,572,and 556.The qualified and unqualified herbal pieces can be also identified by the relative abundances of DDAs.The RSD of the relative abundances of some character ions at m/z 556,586,and 590 were 13.53%,4.03%,and 12.03%,respectively.So this in situ analytical method can identify both the types of Aconitum preparata and their quality.It provides the following advantages in the analysis of Chinese herbs:fast detection without much pretreatment,high-throughput analysis,and reduction of pollution without any organic solvent.展开更多
The Maoping tungsten deposit is located in the Nanling W-Sn metallogenic belt in South China.Greisen and quartz vein types of mineralization developed in this deposit.Protolithionite occurs in the granite.Zinnwaldite ...The Maoping tungsten deposit is located in the Nanling W-Sn metallogenic belt in South China.Greisen and quartz vein types of mineralization developed in this deposit.Protolithionite occurs in the granite.Zinnwaldite is occurs mainly in greisen and wolframite-quartz veins whereas phengite is found in the underground quartz veinlets.In granite and greisen,protolithionite,and zinnwaldite are partly replaced by Li-phengite.LA-ICP-MS trace element analyses of micas and wolframite are employed to characterize the ore-forming source and evolution of ore forming fluids.Micas show compositional variation trend in vertical directions with a decrease of W,Sn,Nb,and Ta and an increase of MgO,V,Ni,and Co.Wolframite in greisen has higher Mo,Sn,Nb,Ta,and REEs than those in quartz veins.All wolframites show similar REE patterns with enrichment of HREE.Wolframites in greisen and quartz veins have negative Eu anomalies,while wolframites in quartz veinlet display positive Eu anomalies.Compositions of mica and wolframite from different mining levels of the Maoping deposit suggest that the ore-forming fluids are dominated by magmatic hydrothermal fluids in the deep with a slight addition of meteoric water in the shallow.Brittle fractureinduced depressurization and fluid mixing controlled the evolution of ore-forming fluids and possibly lead to the wolframite deposition.展开更多
Arsenic pollution poses a serious threat to human health,and is one of the most concerning environmental problems worldwide.The adsorption,fixation,and dissolution behaviors of arsenic on the surface of iron-(hydr-)ox...Arsenic pollution poses a serious threat to human health,and is one of the most concerning environmental problems worldwide.The adsorption,fixation,and dissolution behaviors of arsenic on the surface of iron-(hydr-)oxides influence the environmental routes of arsenic cycle geochemistry.Both inner-sphere and outer-sphere adsorption configurations of arsenic on iron oxides have been proposed based on X-ray adsorption spectra.However,there is no systematic study on the in situ speciation analysis and adsorption kinetics of these species at such interfaces,because of the lack of an efficient monitoring strategy.The correlation of surface speciation and environmental stability is still unknown.Here,a shell-isolated SiO_(2)@Ag@Au-based surface-enhanced Raman spectroscopy(SERS)platform was developed for speciation analysis of the adsorbed arsenic species by eliminating the chemical interaction between arsenic and silver.Using ferrihydrite as a typical iron oxide,the intrinsic Raman spectra of the inner-sphere(~830 cm^(−1))and outer-sphere(~660 cm^(−1))complexes at the adsorption interface were identified.For the first time,the in situ kinetic monitoring of the formation and transformation of these species was realized.By correlating the speciation to the sequential extraction results,the environmental stability of arsenic on ferrihydrite was shown to be closely related to the adsorption configuration.It was shown that stability can be significantly promoted by transforming loosely bonded species(outer-sphere complexes)into inner-sphere structures.Our work demonstrated the applicability of SERS with shell-isolated plasmonic particles for arsenic geochemical cycle monitoring and mechanism studies.It also provided a convenient tool for developing effective strategies for arsenic pollutant control and abatement.展开更多
Mica exhibits a relatively high Rb/Sr ratio and possesses a closure temperature for the Rb-Sr isotope system that is higher than the ore-forming temperature range of low-to medium-temperature deposits.Consequently,uti...Mica exhibits a relatively high Rb/Sr ratio and possesses a closure temperature for the Rb-Sr isotope system that is higher than the ore-forming temperature range of low-to medium-temperature deposits.Consequently,utilizing the laser ablation(LA)technique for in situ Rb-Sr dating in mica constitutes a significant methodology for resolving the mineralization chronology of low-to medium-temperature hydrothermal ore deposits.In this study,we employed a combination of a triple quadrupole inductively coupled plasma mass spectrometer(ICP-MS/MS)and 193 nm LA system with SF_6as the reaction gas to achieve interference removal of~(87)Rb~+on~(87)Sr~+.We then developed an in situ Rb-Sr dating method for mica.In addition,an investigation was conducted to identify the factors that could influence the analytical accuracy of the method.Subsequently,we applied the developed method to carry out in situ Rb-Sr dating for the ZBH-25 biotite,a national primary reference material(GBW04439)for K-Ar dating,and yielded a younger age(ca.12%,relative standard deviation,RSD)than the reference K-Ar age when using NIST SRM 610 as the reference material for external calibration.This finding indicated that in the process of determining Rb-Sr ages for mica by LA-ICP-MS/MS,there are significant matrix effects between the NIST SRM 610 and the mica samples,resulting in inaccurate Rb-Sr ages.In response to this issue,a two-step calibration method is proposed here.Based on external calibration using NIST SRM 610,ZBH-25 biotite is employed as a second external reference material to perform a second calibration of the sample data to correct the matrix effect between the glass standards and the natural mica samples,thereby improving the accuracy of Rb-Sr dating by LA-ICP-MS/MS.Using the proposed method,in situ Rb-Sr dating by LA-ICP-MS/MS was performed on mica samples from monzonite exposed in Mt.Dromedary,New South Wales,Australia,porphyritic granodiorite in Fangshan pluton and albionite granite in the Gyirong area of Tibet.The obtained Rb-Sr age results show agreement with the recommended values within the analytical uncertainty,which serves to validate the accuracy and effectiveness of the proposed method.展开更多
FeTiOx has been recognized as an environmental-friendly and cost-effective catalyst for selective catalytic reduction(SCR)of NOx with NH3.Aimed at further improving the low-temperature DeNOx efficiency of FeTiOx catal...FeTiOx has been recognized as an environmental-friendly and cost-effective catalyst for selective catalytic reduction(SCR)of NOx with NH3.Aimed at further improving the low-temperature DeNOx efficiency of FeTiOx catalyst,a simple strategy of CeO_(2) doping was proposed.The low-temperature(<250°C)NH3-SCR activity of FeTiOx catalyst could be dramatically enhanced by CeO2 doping,and the optimal composition of the catalyst was confirmed as FeCe_(0.2)TiOx,which performed a NOx conversion of 90%at ca.200°C.According to X-ray diffraction(XRD),Raman spectra and X-ray absorption fine structure spectroscopy(XAFS)analysis,FeCe_(0.2)TiOx showed low crystallinity,with Fe and Ce species well mixed with each other.Based on the fitting results of extended X-ray absorption fine structure(EXAFS),a unique Ce-O-Fe structure was formed in FeCe_(0.2)TiOx catalyst.The well improved specific surface area and the newly formed Ce-O-Fe structure dramatically contributed to the improvement of the redox property of FeCe_(0.2)TiOx catalyst,which was well confirmed by H2-temperature-programmed reduction(H2-TPR)and in situ XAFS experiments.Such enhanced redox capability could benefit the activation of NO and NH_(3) at low temperatures for NOx removal.The detailed reaction mechanism study further suggested that the facile oxidative dehydrogenation of NH_(3) to highly reactive-NH_(2) played a key role in enhancing the low-temperature NH_(3)-SCR performance of FeCe_(0.2)TiOx catalyst.展开更多
基金supported by the Elsa-Neumann-Stipendium(Humboldt-Universität zu Berlin)supported by the Fyssen Foundation and the Alexander Von Humboldt Foundation.
文摘Examples of photoluminescence(PL)are being reported with increasing frequency in a wide range of organisms from diverse ecosystems.However,the chemical basis of this PL remains poorly defined,and our understanding of its potential ecological function is still superficial.Among mammals,recent analyses have identified free-base por-phyrins as the compounds responsible for the reddish ultraviolet-induced photoluminescence(UV-PL)observed in the pelage of springhares and hedgehogs.However,the localization of the pigments within the hair largely remains to be determined.Here,we use photoluminescence multispectral imaging emission and excitation spec-troscopy to detect,map,and characterize porphyrinic compounds in skin appendages in situ.We also document new cases of mammalian UV-PL caused by free-base porphyrins in distantly related species.Spatial distribution of the UV-PL is strongly suggestive of an endogenous origin of the porphyrinic compounds.We argue that reddish UV-PL is predominantly observed in crepuscular and nocturnal mammals because porphyrins are photodegradable.Con-sequently,this phenomenon may not have a specific function in intra-or interspecific communication but rather represents a byproduct of potentially widespread physiological processes.
基金supported by the National Natural Science Foundation of China(No.81073040,81274046)National Basic Research Program of China(973 Program)(Nos.2011CB505300,2011CB505305)the Special Fund for Quality Inspection Administration Public Welfare Scientific Research Funding(No.201204001).
文摘In this study,an extend application was developed to in situ analyze the herbal pieces of Aconitum plants by Direct Analysis in Real Time Mass Spectrometry(DART-MS).Nearly all aconitine-type alkaloids can be desorbed and ionized in this method,including diester diterpenoid aconitines(DDAs),monoester diterpenoid aconitines(MDAs)and some other diterpenoid aconitines.The spectra of in situ analysis for the herbal pieces of aconitum plants are similar with that of their extracts.Radix Aconiti and Radix Aconiti Kusnezoffii can be distinguished from each other by the intensity differences of character fragment ions from MDAs,such as m/z 586,572,and 556.The qualified and unqualified herbal pieces can be also identified by the relative abundances of DDAs.The RSD of the relative abundances of some character ions at m/z 556,586,and 590 were 13.53%,4.03%,and 12.03%,respectively.So this in situ analytical method can identify both the types of Aconitum preparata and their quality.It provides the following advantages in the analysis of Chinese herbs:fast detection without much pretreatment,high-throughput analysis,and reduction of pollution without any organic solvent.
基金the National Key R&D Program of China(2016YFC0600207)Key Program of Natural Science Foundation of China(41830428)the"CAS Hundred Talents"Project to JF Gao.We are grateful to Dr.Juan Li at the School of Earth Sciences and Engineering,Nanjing University for taking BSE images.We also thank the staff of the Nanjing FocuMS Technology Co.Ltd.for their kind help in in situ LA-ICP-MS analysis.Finally,thanks for Helene Legros,Lili Chen,Guanglai Li,and Zeying Zhu's help and advice.
文摘The Maoping tungsten deposit is located in the Nanling W-Sn metallogenic belt in South China.Greisen and quartz vein types of mineralization developed in this deposit.Protolithionite occurs in the granite.Zinnwaldite is occurs mainly in greisen and wolframite-quartz veins whereas phengite is found in the underground quartz veinlets.In granite and greisen,protolithionite,and zinnwaldite are partly replaced by Li-phengite.LA-ICP-MS trace element analyses of micas and wolframite are employed to characterize the ore-forming source and evolution of ore forming fluids.Micas show compositional variation trend in vertical directions with a decrease of W,Sn,Nb,and Ta and an increase of MgO,V,Ni,and Co.Wolframite in greisen has higher Mo,Sn,Nb,Ta,and REEs than those in quartz veins.All wolframites show similar REE patterns with enrichment of HREE.Wolframites in greisen and quartz veins have negative Eu anomalies,while wolframites in quartz veinlet display positive Eu anomalies.Compositions of mica and wolframite from different mining levels of the Maoping deposit suggest that the ore-forming fluids are dominated by magmatic hydrothermal fluids in the deep with a slight addition of meteoric water in the shallow.Brittle fractureinduced depressurization and fluid mixing controlled the evolution of ore-forming fluids and possibly lead to the wolframite deposition.
基金the National Natural Science Foundation of China(Nos.22106147 and 22076052)Natural Science Foundation of Hubei Province(No.2021CFB131)+1 种基金China Postdoctoral Science Foundation(No.2021M703005)the Fundamental Research Funds for the Central Universities,China University of Geosciences(Wuhan)(No.G1323521102).
文摘Arsenic pollution poses a serious threat to human health,and is one of the most concerning environmental problems worldwide.The adsorption,fixation,and dissolution behaviors of arsenic on the surface of iron-(hydr-)oxides influence the environmental routes of arsenic cycle geochemistry.Both inner-sphere and outer-sphere adsorption configurations of arsenic on iron oxides have been proposed based on X-ray adsorption spectra.However,there is no systematic study on the in situ speciation analysis and adsorption kinetics of these species at such interfaces,because of the lack of an efficient monitoring strategy.The correlation of surface speciation and environmental stability is still unknown.Here,a shell-isolated SiO_(2)@Ag@Au-based surface-enhanced Raman spectroscopy(SERS)platform was developed for speciation analysis of the adsorbed arsenic species by eliminating the chemical interaction between arsenic and silver.Using ferrihydrite as a typical iron oxide,the intrinsic Raman spectra of the inner-sphere(~830 cm^(−1))and outer-sphere(~660 cm^(−1))complexes at the adsorption interface were identified.For the first time,the in situ kinetic monitoring of the formation and transformation of these species was realized.By correlating the speciation to the sequential extraction results,the environmental stability of arsenic on ferrihydrite was shown to be closely related to the adsorption configuration.It was shown that stability can be significantly promoted by transforming loosely bonded species(outer-sphere complexes)into inner-sphere structures.Our work demonstrated the applicability of SERS with shell-isolated plasmonic particles for arsenic geochemical cycle monitoring and mechanism studies.It also provided a convenient tool for developing effective strategies for arsenic pollutant control and abatement.
基金supported by the National Natural Science Foundation of China(Grant No.42173035)the Chinese Academy of Sciences“Key Technology Talent”Project。
文摘Mica exhibits a relatively high Rb/Sr ratio and possesses a closure temperature for the Rb-Sr isotope system that is higher than the ore-forming temperature range of low-to medium-temperature deposits.Consequently,utilizing the laser ablation(LA)technique for in situ Rb-Sr dating in mica constitutes a significant methodology for resolving the mineralization chronology of low-to medium-temperature hydrothermal ore deposits.In this study,we employed a combination of a triple quadrupole inductively coupled plasma mass spectrometer(ICP-MS/MS)and 193 nm LA system with SF_6as the reaction gas to achieve interference removal of~(87)Rb~+on~(87)Sr~+.We then developed an in situ Rb-Sr dating method for mica.In addition,an investigation was conducted to identify the factors that could influence the analytical accuracy of the method.Subsequently,we applied the developed method to carry out in situ Rb-Sr dating for the ZBH-25 biotite,a national primary reference material(GBW04439)for K-Ar dating,and yielded a younger age(ca.12%,relative standard deviation,RSD)than the reference K-Ar age when using NIST SRM 610 as the reference material for external calibration.This finding indicated that in the process of determining Rb-Sr ages for mica by LA-ICP-MS/MS,there are significant matrix effects between the NIST SRM 610 and the mica samples,resulting in inaccurate Rb-Sr ages.In response to this issue,a two-step calibration method is proposed here.Based on external calibration using NIST SRM 610,ZBH-25 biotite is employed as a second external reference material to perform a second calibration of the sample data to correct the matrix effect between the glass standards and the natural mica samples,thereby improving the accuracy of Rb-Sr dating by LA-ICP-MS/MS.Using the proposed method,in situ Rb-Sr dating by LA-ICP-MS/MS was performed on mica samples from monzonite exposed in Mt.Dromedary,New South Wales,Australia,porphyritic granodiorite in Fangshan pluton and albionite granite in the Gyirong area of Tibet.The obtained Rb-Sr age results show agreement with the recommended values within the analytical uncertainty,which serves to validate the accuracy and effectiveness of the proposed method.
基金support from the Key Project of National Natural Science Foundation of China(No.21637005)Accelerator Research Organization(KEK)(Japan)for the generous help in XAS experiments conducted at Photon Factory,KEK,Japan(No.2012G537).
文摘FeTiOx has been recognized as an environmental-friendly and cost-effective catalyst for selective catalytic reduction(SCR)of NOx with NH3.Aimed at further improving the low-temperature DeNOx efficiency of FeTiOx catalyst,a simple strategy of CeO_(2) doping was proposed.The low-temperature(<250°C)NH3-SCR activity of FeTiOx catalyst could be dramatically enhanced by CeO2 doping,and the optimal composition of the catalyst was confirmed as FeCe_(0.2)TiOx,which performed a NOx conversion of 90%at ca.200°C.According to X-ray diffraction(XRD),Raman spectra and X-ray absorption fine structure spectroscopy(XAFS)analysis,FeCe_(0.2)TiOx showed low crystallinity,with Fe and Ce species well mixed with each other.Based on the fitting results of extended X-ray absorption fine structure(EXAFS),a unique Ce-O-Fe structure was formed in FeCe_(0.2)TiOx catalyst.The well improved specific surface area and the newly formed Ce-O-Fe structure dramatically contributed to the improvement of the redox property of FeCe_(0.2)TiOx catalyst,which was well confirmed by H2-temperature-programmed reduction(H2-TPR)and in situ XAFS experiments.Such enhanced redox capability could benefit the activation of NO and NH_(3) at low temperatures for NOx removal.The detailed reaction mechanism study further suggested that the facile oxidative dehydrogenation of NH_(3) to highly reactive-NH_(2) played a key role in enhancing the low-temperature NH_(3)-SCR performance of FeCe_(0.2)TiOx catalyst.
