The content of REE(La.Ce.Pr.Nd.Sm) in bastnaesite was measured by synchrotron radiation X-ray fluorescence microprobe.Scanning analysis makes use of excitation of the REE K lines between 33 and 50 keV.SR white beam fr...The content of REE(La.Ce.Pr.Nd.Sm) in bastnaesite was measured by synchrotron radiation X-ray fluorescence microprobe.Scanning analysis makes use of excitation of the REE K lines between 33 and 50 keV.SR white beam from a Wiggler source at the Beijing Electron Positron Collider(BEPC) of the National Laboratory,in order to excite the REE.The bastnaesite from the same mineral area was powdered to particle size≤300 mesh.It was then divided into two parts.One portion was used to be determined by XRF after depositing with oxalate and transforming into oxide.The other was pressed into disk without any binder as the reference sample.The weight and the diamieter of the disk were 15 g and 26 mm respectively.展开更多
The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of...The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),Jordan.The experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by Puri.The experimental and theoretical results are in agreement.In this work,L XRF relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of 18 keV and 23 keV were measured.展开更多
The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disea...The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disease(PD)using synchrotron radiation X-ray fluorescence(SRXRF). PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-terahydropyridine(MPTP) was used for the elemental analysis(e.g., Fe, Cu and Zn) in the substantia nigra pars compacta(SNpc) region of mice brain tissue samples. We found that mice in the MPTP group had higher contents of Fe, Cu and Zn in the SNpc than the control group. After treating the PD mice with rapamycin, the contents of Fe, Cu and Zn were reduced, the dopamine neurons and motor function were rescued correspondingly. The results prompted that the SRXRF provided an ideal method for tracing and analyzing the metal elements in the brain section to assess the pathological changes of PD model and the therapeutic effect of drugs.展开更多
Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in...Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in maintaining normal brain function.However,the dynamic spatial distributions of iron,zinc,calcium,potassium,and copper in a rat brain following ischemic stroke and the association between structural distribution and function remain to be elucidated.In this study,we used a synchrotron radiation-based micro-X-ray fluorescence technique to image element mapping changes in special rat brain regions after ischemic stroke,showing the distribution characteristics of iron,zinc,calcium,potassium,and copper.We demonstrated,for the first time,the consistent dynamic spatial distributions of metal elements at a series of time points(3 h,4.5 h,6 h,12 h,1 d,3 d,5 d,7 d,10 d,14 d,28 d)after brain ischemia,which revealed that the homeostasis of iron,zinc,calcium,potassium,and copper in the brain was disturbed with distinctive change trends,providing clear insights in understanding the underlying pathogenesis of stroke from a novel perspective,thus laying the foundation of further developing new drug targets for stroke treatment.展开更多
1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom se...1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom sediments of the lakes contain detailed geochemical information on展开更多
Background: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process an...Background: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process and distribution of nickel in skin tissues with late phase and early phase of Ni-ACD to understand the mechanisms of metal allergy. Methods: Forty Hartley guinea pigs were divided into four groups according to the NiSO4 sensitizing concentration and the NiSO4 challenged concentration: the 5% NiSO4-group, 5% to 10%(sensitization-challenge;late phase group);10% NiSO4-group, 10% to 10%(sensitization-challenge;early-phase group);and the positive and negative controls. Pathological biopsies were performed on each group. The depth profile of nickel element concentration in the skin of guinea pigs was detected by synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μ-XRF) and micro X-ray absorption near-edge spectroscopy (μ-XANES). Results: In each section, the nickel element concentration in both the 5% NiSO4-group and 10% NiSO4-group was significantly higher than that in the negative control group. In the upper 300-μm section of skin for the early phase group, the nickel element concentration was significantly higher than that in the lower section of skin. In deeper sections (>200 μm) of skin, the concentration of nickel in the early phase group was approximately equal to that in the late phase group. The curve of the late phase group was flat, which means that the nickel element concentration was distributed uniformly by SR-μ-XRF. According to the XANES data for the 10% NiSO4 metal salt solution, structural changes occurred in the skin model sample, indicating that nickel was not present in the Ni^2+ aqueous ionic state but in the nickel-binding protein. Conclusions: This study showed that the distribution of the nickel element concentration in ACD skin tissue was different between the early phase and late phase groups. The nickel element was not present in the Ni^2+ aqueous ionic state but bound with certain proteins to form a complex in the stratum corneum in ACD model tissue.展开更多
A method using synchrotron radiation X-ray fluorescence analysis to in situ determine trace elements during protein electrophoretically separating process was established. The distribution of elements in protein bands...A method using synchrotron radiation X-ray fluorescence analysis to in situ determine trace elements during protein electrophoretically separating process was established. The distribution of elements in protein bands for human liver cytosolic sample separated by SDS-PAGE was analyzed a-long polyacrylamide gel. The results showed that the protein fraction of peak III in cvtosol was mainly composed of metal ion Zn-associated proteins, being in agreement with that given by atomic absorption spectrometry. Thus, it demonstrated the feasibility of this novel technique for in situ analysis of trace elements in protein bands.展开更多
X-ray fluorescence(XRF) scan methodology is important for elemental mapping of samples at a synchrotron radiation facility. To save the experiment time and improve the experiment efficiency, one should develop an effi...X-ray fluorescence(XRF) scan methodology is important for elemental mapping of samples at a synchrotron radiation facility. To save the experiment time and improve the experiment efficiency, one should develop an efficient XRF scan method. In this paper, a new scan mode is presented. It can map arbitrary-shaped areas withou stopping the motors. The control and data acquisition system integrates motor controlling, detector triggering, and data acquisition and storage. The system realizes the arbitrary-shaped 2D-mapping and fluorescence data acquisition synchronously. SR-XRF mapping has been performed with a standard gold mask to verify the validity of this method a beamline BL15U1 of the Shanghai Synchrotron Radiation Facility. The results show that this method reduces the tota scan time and improves the experiment efficiency.展开更多
In order to further understand the sources of PM2.5 in Shanghai air, the synchrotron X-ray fluores- cence microprobe at the BL-4A Beamline of Photon Factory of High Energy Accelerator Research Organization, Japan, was...In order to further understand the sources of PM2.5 in Shanghai air, the synchrotron X-ray fluores- cence microprobe at the BL-4A Beamline of Photon Factory of High Energy Accelerator Research Organization, Japan, was applied to analyze the individual PM2.5 particles collected from Shanghai air in the winter of 2007. Eight categories of emission sources were recognized in these individual particles. The source identification shows that most of the analyzed PM2.5 particles are derived from vehicle exhaust and metallurgical emissions. This suggests that the important emission sources of PM2.5 in Shanghai air would be vehicle exhaust and metallurgical activities.展开更多
Synchrotron X-ray fluorescence analyses of crystal and amorphous clinopyroxene were compared. The results showed that using the synchrotron X-ray as a source of energy, the diffraction X-ray of crystal materials will ...Synchrotron X-ray fluorescence analyses of crystal and amorphous clinopyroxene were compared. The results showed that using the synchrotron X-ray as a source of energy, the diffraction X-ray of crystal materials will seriously affect the X-ray fluorescence analysis. In order to avoid the influence of diffraction, the best way to solve it is to use the monochromatic source, or to have a collimating slit between sample and Si(Li) detector.展开更多
This note deals with the scanning of femoral head slices from both normal and osteoporosis subjects using synchrotron radiation X-ray fluorescence (SRXRF) microprobe technique. The sample preparation and experimental ...This note deals with the scanning of femoral head slices from both normal and osteoporosis subjects using synchrotron radiation X-ray fluorescence (SRXRF) microprobe technique. The sample preparation and experimental apparatus are described in detail. The quantitative computerized tomography (QCT) of elemental distribution, such as Ca, P, K, Fe, Zn, Sr and Pb in bone slice tissue including cartilage, substantial compact and substantial spongy, is investigated. Combined with the correlation between P, K, Zn, Sr and Ca, the loss way of minerals and the physiological functions of some metal elements in bone are also discussed.展开更多
The hard X-ray micro-focusing beamline(BL15U1) of SSRF is dedicated to hard X-ray micro/nanospectrochemical analysis consisting of X-ray fluorescence(XRF), X-ray absorption spectroscopy(XAS) and X-ray diffraction(XRD)...The hard X-ray micro-focusing beamline(BL15U1) of SSRF is dedicated to hard X-ray micro/nanospectrochemical analysis consisting of X-ray fluorescence(XRF), X-ray absorption spectroscopy(XAS) and X-ray diffraction(XRD) techniques. It is one of the most versatile instruments in hard X-ray microscopy science. Since its commission in 2009, BL15U1 has allocated over 25000 h beamtime for users, and about 700 proposals have been executed. The beamline and the experimental end-station were upgraded for several times to facilitate the users' experimental needs and make it more convenient to operate. In this paper, we give a review on the beamline, describing its characteristics, recent technical developments, and a few examples of scientific progresses achieved in recent years on BL15U1.展开更多
X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF ...X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline (BL13W1) are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.展开更多
Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorp...Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorption near edge structure spectroscopy was established to analyze the sulfur concentration and speciation in mature camphor tree leaves (CTLs),which were sampled from 5 local fields in Shanghai,China.Annual SO2 concentration,SO42-concentration in atmospheric particulate,SO42-and sulfur concentration in soil were also analyzed to explore the relationship between ambient sulfur sources and the sulfur nutrient cycling in CTLs.Total sulfur concentration in mature camphor tree leaves was 766-1704 mg/kg.The mainly detected sulfur states and their corresponding compounds were +6 (sulfate,include inorganic sulfate and organic sulfate),+5.2 (sulfonate),+2.2 (suloxides),+0.6 (thiols and thiothers),+0.2 (organic sulfides).Total sulfur concentration was strongly correlated with sulfate proportion with a linear correlation coefficient up to 0.977,which suggested that sulfur accumulated in CTLs as sulfate form.Reduced sulfur compounds (organic sulfides,thiols,thioethers,sulfoxide and sulfonate) assimilation was sufficed to meet the nutrient requirement for growth at a balanced level around 526 mg/kg.The sulfate accumulation mainly caused by atmospheric sulfur pollution such as SO2 and airborne sulfate particulate instead of soil contamination.From urban to suburb place,sulfate in mature CTLs decreased as the atmospheric sulfur pollution reduced,but a dramatic increase presented near the seashore,where the marine sulfate emission and maritime activity pollution were significant.The sulfur concentration and speciation in mature CTLs effectively represented the long-term biological accumulation of atmospheric sulfur pollution in local environment.展开更多
Bao Zheng, styled Xi-ren, a native of Luzhou County (Now Hefei, Anhui Province), was born in the second year of Xiangping (the title of Emperor Zhenzong’s reign, A. D. 999 North Song Dynasty) and died in the 7th year...Bao Zheng, styled Xi-ren, a native of Luzhou County (Now Hefei, Anhui Province), was born in the second year of Xiangping (the title of Emperor Zhenzong’s reign, A. D. 999 North Song Dynasty) and died in the 7th year of Jiayou (the title of Emperor Renzong’s reign, A. D. 1062) at the age of 64. In his childhood and youth he was diligent in pursuing his studies. When he was 29 years old, he became a successful candidate in the highest emperial examination and hereafter took official career for more than展开更多
文摘The content of REE(La.Ce.Pr.Nd.Sm) in bastnaesite was measured by synchrotron radiation X-ray fluorescence microprobe.Scanning analysis makes use of excitation of the REE K lines between 33 and 50 keV.SR white beam from a Wiggler source at the Beijing Electron Positron Collider(BEPC) of the National Laboratory,in order to excite the REE.The bastnaesite from the same mineral area was powdered to particle size≤300 mesh.It was then divided into two parts.One portion was used to be determined by XRF after depositing with oxalate and transforming into oxide.The other was pressed into disk without any binder as the reference sample.The weight and the diamieter of the disk were 15 g and 26 mm respectively.
基金supported by the Jordan University of Science and Technology(Grant No.20180167)the SESAME Synchrotron Center Jordan(Grant No.20185004)。
文摘The relative intensities of L-subshell x-ray fluorescence(XRF)for elements with atomic numbers 62≤Z≤83 were measured at two excitation energies,18 keV and 23 keV,using a synchrotron radiation source at a beamline of the Synchrotron Light Center for Experimental Science and Applications in the Middle East(SESAME),Jordan.The experimentally measured results of the relative intensities were compared with the calculated results using the subshell fluorescence yield and the Coster-Kronig transition probabilities recommended by Campbell and the values based on the Dirac-Hartree-Slater model by Puri.The experimental and theoretical results are in agreement.In this work,L XRF relative intensities for the elements Sm,Gd,Tb,Er,Ta,W,Re,Hg,Pb and Bi at energies of 18 keV and 23 keV were measured.
基金Supported by the Ministry of Science and Technology of China(Nos.2012CB825805 and 2012CB932600)National Natural Science Foundation of China(Nos.11179004,21390414,U1232113,U1232114,U1332119 and U1432116)Youth Innovation Promotion Association of CAS
文摘The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases.In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disease(PD)using synchrotron radiation X-ray fluorescence(SRXRF). PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-terahydropyridine(MPTP) was used for the elemental analysis(e.g., Fe, Cu and Zn) in the substantia nigra pars compacta(SNpc) region of mice brain tissue samples. We found that mice in the MPTP group had higher contents of Fe, Cu and Zn in the SNpc than the control group. After treating the PD mice with rapamycin, the contents of Fe, Cu and Zn were reduced, the dopamine neurons and motor function were rescued correspondingly. The results prompted that the SRXRF provided an ideal method for tracing and analyzing the metal elements in the brain section to assess the pathological changes of PD model and the therapeutic effect of drugs.
基金This work was supported by the National Natural Science Foundation of China(No.81501025)the Natural Science Foundation of Hunan Province(Nos.2020JJ4134 and 2016JJ3174).
文摘Ischemic stroke is one of the leading causes of death worldwide,and effective treatment strategies in the chronic phase of this disease remain insufficient.Homeostasis of metals in the brain plays an important role in maintaining normal brain function.However,the dynamic spatial distributions of iron,zinc,calcium,potassium,and copper in a rat brain following ischemic stroke and the association between structural distribution and function remain to be elucidated.In this study,we used a synchrotron radiation-based micro-X-ray fluorescence technique to image element mapping changes in special rat brain regions after ischemic stroke,showing the distribution characteristics of iron,zinc,calcium,potassium,and copper.We demonstrated,for the first time,the consistent dynamic spatial distributions of metal elements at a series of time points(3 h,4.5 h,6 h,12 h,1 d,3 d,5 d,7 d,10 d,14 d,28 d)after brain ischemia,which revealed that the homeostasis of iron,zinc,calcium,potassium,and copper in the brain was disturbed with distinctive change trends,providing clear insights in understanding the underlying pathogenesis of stroke from a novel perspective,thus laying the foundation of further developing new drug targets for stroke treatment.
基金supported by the RFBR projects 13-05-00871,14-02-00631
文摘1 Introduction Annually laminated(varve)sedimentary deposits are considered as one of the most important archives,since they offer precise temporal information(years)in combination with high time resolutions.Bottom sediments of the lakes contain detailed geochemical information on
基金the grants from National Natural Science Foundation of China (No.81373175)CAMS Innovation Fund for Medical Sciences (No.2016-I2M-1003).
文摘Background: Nickel-induced allergic contact dermatitis (Ni-ACD) is a global health problem. More detailed knowledge on the skin uptake of haptens is required. This study aimed to investigate the penetration process and distribution of nickel in skin tissues with late phase and early phase of Ni-ACD to understand the mechanisms of metal allergy. Methods: Forty Hartley guinea pigs were divided into four groups according to the NiSO4 sensitizing concentration and the NiSO4 challenged concentration: the 5% NiSO4-group, 5% to 10%(sensitization-challenge;late phase group);10% NiSO4-group, 10% to 10%(sensitization-challenge;early-phase group);and the positive and negative controls. Pathological biopsies were performed on each group. The depth profile of nickel element concentration in the skin of guinea pigs was detected by synchrotron radiation micro X-ray fluorescence spectroscopy (SR-μ-XRF) and micro X-ray absorption near-edge spectroscopy (μ-XANES). Results: In each section, the nickel element concentration in both the 5% NiSO4-group and 10% NiSO4-group was significantly higher than that in the negative control group. In the upper 300-μm section of skin for the early phase group, the nickel element concentration was significantly higher than that in the lower section of skin. In deeper sections (>200 μm) of skin, the concentration of nickel in the early phase group was approximately equal to that in the late phase group. The curve of the late phase group was flat, which means that the nickel element concentration was distributed uniformly by SR-μ-XRF. According to the XANES data for the 10% NiSO4 metal salt solution, structural changes occurred in the skin model sample, indicating that nickel was not present in the Ni^2+ aqueous ionic state but in the nickel-binding protein. Conclusions: This study showed that the distribution of the nickel element concentration in ACD skin tissue was different between the early phase and late phase groups. The nickel element was not present in the Ni^2+ aqueous ionic state but bound with certain proteins to form a complex in the stratum corneum in ACD model tissue.
文摘A method using synchrotron radiation X-ray fluorescence analysis to in situ determine trace elements during protein electrophoretically separating process was established. The distribution of elements in protein bands for human liver cytosolic sample separated by SDS-PAGE was analyzed a-long polyacrylamide gel. The results showed that the protein fraction of peak III in cvtosol was mainly composed of metal ion Zn-associated proteins, being in agreement with that given by atomic absorption spectrometry. Thus, it demonstrated the feasibility of this novel technique for in situ analysis of trace elements in protein bands.
文摘X-ray fluorescence(XRF) scan methodology is important for elemental mapping of samples at a synchrotron radiation facility. To save the experiment time and improve the experiment efficiency, one should develop an efficient XRF scan method. In this paper, a new scan mode is presented. It can map arbitrary-shaped areas withou stopping the motors. The control and data acquisition system integrates motor controlling, detector triggering, and data acquisition and storage. The system realizes the arbitrary-shaped 2D-mapping and fluorescence data acquisition synchronously. SR-XRF mapping has been performed with a standard gold mask to verify the validity of this method a beamline BL15U1 of the Shanghai Synchrotron Radiation Facility. The results show that this method reduces the tota scan time and improves the experiment efficiency.
基金Supported by Knowledge Innovation Project of Chinese Academy of Sciences (KJCX3.SYW.N3) National Natural Science Foundation of China (10775172, 10675159)performance under approval of Photon Factory (PF) Program Advisory Committee(Proposal No.2007G502)
文摘In order to further understand the sources of PM2.5 in Shanghai air, the synchrotron X-ray fluores- cence microprobe at the BL-4A Beamline of Photon Factory of High Energy Accelerator Research Organization, Japan, was applied to analyze the individual PM2.5 particles collected from Shanghai air in the winter of 2007. Eight categories of emission sources were recognized in these individual particles. The source identification shows that most of the analyzed PM2.5 particles are derived from vehicle exhaust and metallurgical emissions. This suggests that the important emission sources of PM2.5 in Shanghai air would be vehicle exhaust and metallurgical activities.
文摘Synchrotron X-ray fluorescence analyses of crystal and amorphous clinopyroxene were compared. The results showed that using the synchrotron X-ray as a source of energy, the diffraction X-ray of crystal materials will seriously affect the X-ray fluorescence analysis. In order to avoid the influence of diffraction, the best way to solve it is to use the monochromatic source, or to have a collimating slit between sample and Si(Li) detector.
基金This work was supported by the National Natural Science Foundation of China (Grant No. 19875074) Research Foundation of the Chinese Academy of Sciences (Grant No. KJ951-41-409) and the National Laboratory of Beijing Electron Positron Collider (Grant
文摘This note deals with the scanning of femoral head slices from both normal and osteoporosis subjects using synchrotron radiation X-ray fluorescence (SRXRF) microprobe technique. The sample preparation and experimental apparatus are described in detail. The quantitative computerized tomography (QCT) of elemental distribution, such as Ca, P, K, Fe, Zn, Sr and Pb in bone slice tissue including cartilage, substantial compact and substantial spongy, is investigated. Combined with the correlation between P, K, Zn, Sr and Ca, the loss way of minerals and the physiological functions of some metal elements in bone are also discussed.
基金Supported by the National Natural Science Foundation of China(Nos.U1332117 and U1332120)Natural Science Foundation of Shanghai(No.14ZR1448200)
文摘The hard X-ray micro-focusing beamline(BL15U1) of SSRF is dedicated to hard X-ray micro/nanospectrochemical analysis consisting of X-ray fluorescence(XRF), X-ray absorption spectroscopy(XAS) and X-ray diffraction(XRD) techniques. It is one of the most versatile instruments in hard X-ray microscopy science. Since its commission in 2009, BL15U1 has allocated over 25000 h beamtime for users, and about 700 proposals have been executed. The beamline and the experimental end-station were upgraded for several times to facilitate the users' experimental needs and make it more convenient to operate. In this paper, we give a review on the beamline, describing its characteristics, recent technical developments, and a few examples of scientific progresses achieved in recent years on BL15U1.
基金Supported by National Natural Science Foundation of China (10805071, 10705020)Major Research Plan of National Natural Science Foundation of China (2010CB834301)Chinese Academy of Sciences Key Project of International Co-operation(GJHZ09058)
文摘X-ray fluorescence CT is a non-destructive technique for detecting elemental composition and distribution inside a specimen. In this paper, the first experimental results of X-ray fluorescence CT obtained at the SSRF X-ray imaging beamline (BL13W1) are described. The test samples were investigated and the 2D elemental image was reconstructed using a filtered back-projection algorithm. In the sample the element Cd was observed. Up to now, the X-ray fluorescence CT could be carried out at the SSRF X-ray imaging beamline.
基金supported by the National Natural Science Foundation of China(No.11079049,11005141,10775150)the Major Project of Knowledge Innovation Program of Chinese Academy of Sciences(No.KJCX3.SYW.N3)
文摘Analyzing and understanding the effects of ambient pollution on plants is getting more and more attention as a topic of environmental biology.A method based on synchrotron radiation X-ray fluorescence and X-ray absorption near edge structure spectroscopy was established to analyze the sulfur concentration and speciation in mature camphor tree leaves (CTLs),which were sampled from 5 local fields in Shanghai,China.Annual SO2 concentration,SO42-concentration in atmospheric particulate,SO42-and sulfur concentration in soil were also analyzed to explore the relationship between ambient sulfur sources and the sulfur nutrient cycling in CTLs.Total sulfur concentration in mature camphor tree leaves was 766-1704 mg/kg.The mainly detected sulfur states and their corresponding compounds were +6 (sulfate,include inorganic sulfate and organic sulfate),+5.2 (sulfonate),+2.2 (suloxides),+0.6 (thiols and thiothers),+0.2 (organic sulfides).Total sulfur concentration was strongly correlated with sulfate proportion with a linear correlation coefficient up to 0.977,which suggested that sulfur accumulated in CTLs as sulfate form.Reduced sulfur compounds (organic sulfides,thiols,thioethers,sulfoxide and sulfonate) assimilation was sufficed to meet the nutrient requirement for growth at a balanced level around 526 mg/kg.The sulfate accumulation mainly caused by atmospheric sulfur pollution such as SO2 and airborne sulfate particulate instead of soil contamination.From urban to suburb place,sulfate in mature CTLs decreased as the atmospheric sulfur pollution reduced,but a dramatic increase presented near the seashore,where the marine sulfate emission and maritime activity pollution were significant.The sulfur concentration and speciation in mature CTLs effectively represented the long-term biological accumulation of atmospheric sulfur pollution in local environment.
基金Project supported by the National Natural Science Foundation of China and 8.5 Major Project Foundation of Academia Sinica.
文摘Bao Zheng, styled Xi-ren, a native of Luzhou County (Now Hefei, Anhui Province), was born in the second year of Xiangping (the title of Emperor Zhenzong’s reign, A. D. 999 North Song Dynasty) and died in the 7th year of Jiayou (the title of Emperor Renzong’s reign, A. D. 1062) at the age of 64. In his childhood and youth he was diligent in pursuing his studies. When he was 29 years old, he became a successful candidate in the highest emperial examination and hereafter took official career for more than