The Pb-monitoring program was extended for 6 years from 2002 to 2007 at 17 representative urban sites （6 traffic, 5 industrial, and 6 residential sites）, and 3 suburban sites to assess the lead pollution in fine par...The Pb-monitoring program was extended for 6 years from 2002 to 2007 at 17 representative urban sites （6 traffic, 5 industrial, and 6 residential sites）, and 3 suburban sites to assess the lead pollution in fine particulate matter （PM2.5） after phasing out leaded gasoline in Shanghai. Compared with Pb levels reported in other places, the Pb pollution in Shanghai is still serious after phasing out leaded gasoline, which remains at high concentration range （213-176 ng/m^3） in PM2.5 in winter. Significant spatial variation of Pb concentrations and strong seasonal variation of higher Pb concentration in winter than that in summer were detected. The size distribution of Pb in particulate matter has a unimodat mode that peaks at approximately 0.154-1.59 μm particle diameter, indicating that Pb is mainly concentrated in fine fraction. Lead in the fine fraction is enriched by a factor of 103-104 relative to Pb abundance in crust. Eight categories of Pb pollution sources were identified in the PM2.5 in the winter of 2007 in Shanghai. The important emission sources among them are vehicle exhaust derived from combustion of unleaded gasoline, metaUurgic industry emission, and coal combustion emission.展开更多
We have directly investigated the chemical state of the Pd species in a real l-gas sensor device by examining the l-fluorescence X-ray absorption fine structure. The l-gas sensor device was heavily damaged by a heatin...We have directly investigated the chemical state of the Pd species in a real l-gas sensor device by examining the l-fluorescence X-ray absorption fine structure. The l-gas sensor device was heavily damaged by a heating process in which the temperature was ill-controlled, resulting in decrease of methane selectivity. We found that the Pd O in the fresh l-gas sensor was reduced to Pd metal particles as the methane selectivity decreased. Based on the investigation results, we modified the device structure so as to heat up homogeneously. The lifetime of the sensor was then successfully increased by more than 5 years.展开更多
Ductal carcinoma in-situ (DCIS) has been visualized by 2D XDFI (X-ray dark-field imaging) and further by a 3D X-ray CT, and the data was acquired by the X-ray optics DEI (diffraction-enhanced imaging). A newly made al...Ductal carcinoma in-situ (DCIS) has been visualized by 2D XDFI (X-ray dark-field imaging) and further by a 3D X-ray CT, and the data was acquired by the X-ray optics DEI (diffraction-enhanced imaging). A newly made algorithm was used for CT. Data of 900 projections with interval of 0.2 degrees were used. Ductus lactiferi, microcalci-fication in a 3D form have been clearly visible. The spatial resolution available was approximately 30μm.展开更多
To investigate the characteristic and sources of the fine particulate matter(PM2.5),and the major sources affecting particulate air pollution in Shanghai,China,the individual aerosol particles were analyzed using the ...To investigate the characteristic and sources of the fine particulate matter(PM2.5),and the major sources affecting particulate air pollution in Shanghai,China,the individual aerosol particles were analyzed using the synchrotron radiation micro-beam X-ray fluorescence analysis(?-SXRF),and the PM2.5 multi-elements were determined by the inductively coupled plasma mass spectrometer(ICP-MS).The results show that the mass concentration and chemical elements have seasonal variation,and the enrichment factors show that the chemical elements in the inhalable particles could come from the earth crust and anthropogenic pollution.The extent of metal pollution was assessed by comparing the measured concentrations with those reported in the literature.Nine categories of PM2.5 pollution sources identified at the center of Shanghai show that the vehicle exhaust,emission of metallurgic industry and coal combustion are important.展开更多
Structures of membrane protein in solution are different from that in crystal phase. We present the primary results of small angle x-ray scattering （SAXS） resolved topological structures of a light harvesting antenn...Structures of membrane protein in solution are different from that in crystal phase. We present the primary results of small angle x-ray scattering （SAXS） resolved topological structures of a light harvesting antenna membrane protein complex LH2 from photosynthetic bacteria Rhodopseudomonas acidophila in detergent solution for the first time. Our results show that the elliptical shape of the LH2 complex in solution clearly deviates from its circular structure in crystal phase determined by x-ray diffraction. This result provides an insight into the structure and function interplay in LH2.展开更多
The high-pressure behaviour of the superconductor MgB_(2) with a hexagonal structure has been investigated by the in situ synchrotron radiation x-ray diffraction method under pressures up to 42.2 GPa in a diamond anvi...The high-pressure behaviour of the superconductor MgB_(2) with a hexagonal structure has been investigated by the in situ synchrotron radiation x-ray diffraction method under pressures up to 42.2 GPa in a diamond anvil cell. An abrupt decrease of about 7% in the unit cell volume of this material occurs in the pressure range of 26.3-30.2 GPa. A split of the Raman spectrum was also observed. The jump of the compression curve and Raman spectrum are ascribed to an isostructural transition in MgB_(2 ) at a pressure of 30.2 GPa.展开更多
ALG-2(a gene product of PDCD6) is a 22-kD protein containing five serially repetitive EF-hand structures and belongs to the penta-EF-hand(PEF) family,including the subunits of typical calpains.ALG-2 is the most conser...ALG-2(a gene product of PDCD6) is a 22-kD protein containing five serially repetitive EF-hand structures and belongs to the penta-EF-hand(PEF) family,including the subunits of typical calpains.ALG-2 is the most conserved protein among the PEF family members and its homologs are widely found in eukaryotes.X-ray crystal structures of various PEF proteins including ALG-2 have common features:presence of eightα-helices and dimer formation via paired EF5s that are positioned in anti-parallel orientation.ALG-2 forms a homodimer and a heterodimer with its closest paralog peflin.Like calmodulin,a well-known four-EF-hand protein,ALG-2 interacts with various proteins in a Ca2+-dependent fashion,but the binding motifs are completely different.With some exceptions,ALG-2-interacting proteins commonly contain Pro-rich regions,and ALG-2 recognizes at least two distinct Pro-containing motifs:PPYP(X) nYP(X,variable;n=4 in ALIX and PLSCR3) and PXPGF(represented by Sec31A) .A shorter alternatively spliced isoform,lacking two residues and designated ALG-2 GF122,does not bind ALIX but maintains binding capacity to Sec31A.X-ray crystal structural analyses have revealed that binding of calcium ions induces the configuration of the side chain of R125 so that it opens Pocket 1,which accepts PPYP,but Pocket 1 remains closed in the case of ALG-2 GF122.ALG-2 dimer has two ligand-binding sites,each in a monomer molecule,and appears to function as a Ca2+-dependent adaptor protein to either stabilize a preformed complex or to bridge two proteins on scaffolds in systems of the endosomal sorting complex required for transport(ESCRT) and ER-to-Golgi transport.展开更多
In order to explore the mechanism of moss as air pollution biomonitor, the moss samples were exposed in a pollution site of Shanghai Institute of Steel Research (SISR) and a control site of Shanghai Institute of Appli...In order to explore the mechanism of moss as air pollution biomonitor, the moss samples were exposed in a pollution site of Shanghai Institute of Steel Research (SISR) and a control site of Shanghai Institute of Applied Physics (SIAP) simultaneously for one month. The concentrations of trace elements in the micro areas of leaf and stem, as well as in the whole moss tissue, were determined using synchrotron radiation X-ray fluorescence (SRXRF) method. The distributions of some metal elements such as Pb, Cu, Fe, Ni, Mn, Zn, Ca and K in the leaf surface and the stem slice were obtained. The results showed that the metallic ions were not evenly distributed after adsorption. In particular, some elements of K, Ni, Fe, Pb, etc., were concentrated in the leaf apex and the intermediate rib. Under pollution condition, the excessive Pb was adsorbed and deposited in the leaf. It caused serious damage to plant growth and ultrastructure, also suppressed moss’ normal absorption to the nutritive elements of K, Ca, etc.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
Chenguodaite, approved by IMA-CNMMN (2004-042a), was discovered in the Bunan quartz vein-type gold deposit in the gold district of East Shandong Peninsula. The mineral occurs in high grade Au-Ag-Cu ores, coexisting wi...Chenguodaite, approved by IMA-CNMMN (2004-042a), was discovered in the Bunan quartz vein-type gold deposit in the gold district of East Shandong Peninsula. The mineral occurs in high grade Au-Ag-Cu ores, coexisting with galena, chalcopyrite, hessite, electrum, unnamed Ag6TeS2 and Ag16FeBiTe3S8, enclosed and replaced by native silver and acanthite. In the reflected light microscope, the mineral has light gray color, indistinguishable anistropism and hardness around 2―3. The color indices of chenguodaite relative to ICE C illuminator are: x=0.3027, y=0.3076, Y=25.78%, λd=474 nm, Pe=3.68%, similar to those of canfieldite. The average chemical composition from 16 microprobe analyses is Ag8.97Fe1.00Te1.99S4.04, idealized to Ag9FeTe2S4. The polycrystalline X-ray diffraction of chenguodaite by Gandolfi camera and synchrotron oscillation photography results in 67 reflections with the 12 strongest being (relative intensity in bracket): 6.742(69), 6.416(39), 5.951(33), 3.265(100), 2.981(24), 2.649(22), 2.25(24), 2.188(71), 2.142(22), 2.123(31), 2.044(23), 1.949(33), which are indexed to a primitive orthorhombic cell with a=12.769 (2) , b= 14.814(2), c= 16.233 (1) , V= 3070.63, Z = 9, Dcal.=6.85 g/cm3. The name is for the late Prof. Chen Guoda, a famous Chinese geologist and the founder of Diwa-Geodepression theory of tectonics.展开更多
In-situ SR-XRD measurements revealed that the crystallization process in Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass is significantly different from that in tradi-tional glasses. Subsequent heating at 10 GPa conv...In-situ SR-XRD measurements revealed that the crystallization process in Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass is significantly different from that in tradi-tional glasses. Subsequent heating at 10 GPa converts the sample from amorphous phase into the metastable fcc phase and then leads to the fcc phase back to the amorphous phase, indicating that there exists ’reversible’ phase transition phe-nomena in the material under high pressure and high tem-perature.展开更多
基金supported by the National Natural Sci-ence Foundation of China (No. 10775172, 10675159)the Major Project of Knowledge Innovation Program of Chinese Academy of Sciences (No.KJCX3.SYW.N3)This work has been performed under the approval of the Photon Factory (PF) Program Advisory Committee (No.2007G502)
文摘The Pb-monitoring program was extended for 6 years from 2002 to 2007 at 17 representative urban sites （6 traffic, 5 industrial, and 6 residential sites）, and 3 suburban sites to assess the lead pollution in fine particulate matter （PM2.5） after phasing out leaded gasoline in Shanghai. Compared with Pb levels reported in other places, the Pb pollution in Shanghai is still serious after phasing out leaded gasoline, which remains at high concentration range （213-176 ng/m^3） in PM2.5 in winter. Significant spatial variation of Pb concentrations and strong seasonal variation of higher Pb concentration in winter than that in summer were detected. The size distribution of Pb in particulate matter has a unimodat mode that peaks at approximately 0.154-1.59 μm particle diameter, indicating that Pb is mainly concentrated in fine fraction. Lead in the fine fraction is enriched by a factor of 103-104 relative to Pb abundance in crust. Eight categories of Pb pollution sources were identified in the PM2.5 in the winter of 2007 in Shanghai. The important emission sources among them are vehicle exhaust derived from combustion of unleaded gasoline, metaUurgic industry emission, and coal combustion emission.
基金High Energy Accelerator Organization under Proposal Number 2012G680
文摘We have directly investigated the chemical state of the Pd species in a real l-gas sensor device by examining the l-fluorescence X-ray absorption fine structure. The l-gas sensor device was heavily damaged by a heating process in which the temperature was ill-controlled, resulting in decrease of methane selectivity. We found that the Pd O in the fresh l-gas sensor was reduced to Pd metal particles as the methane selectivity decreased. Based on the investigation results, we modified the device structure so as to heat up homogeneously. The lifetime of the sensor was then successfully increased by more than 5 years.
文摘Ductal carcinoma in-situ (DCIS) has been visualized by 2D XDFI (X-ray dark-field imaging) and further by a 3D X-ray CT, and the data was acquired by the X-ray optics DEI (diffraction-enhanced imaging). A newly made algorithm was used for CT. Data of 900 projections with interval of 0.2 degrees were used. Ductus lactiferi, microcalci-fication in a 3D form have been clearly visible. The spatial resolution available was approximately 30μm.
基金Supported by grants from the Knowledge Innovation Project of the Chinese Academy of Sciences(No.KJCX3.SYW.N3) the National Natural Science Foundation of China(NNSFC,No.10775172)performed under the approval of the Photon Factory(PF)Program Advisory Committee(Proposal No.2007G502)
文摘To investigate the characteristic and sources of the fine particulate matter(PM2.5),and the major sources affecting particulate air pollution in Shanghai,China,the individual aerosol particles were analyzed using the synchrotron radiation micro-beam X-ray fluorescence analysis(?-SXRF),and the PM2.5 multi-elements were determined by the inductively coupled plasma mass spectrometer(ICP-MS).The results show that the mass concentration and chemical elements have seasonal variation,and the enrichment factors show that the chemical elements in the inhalable particles could come from the earth crust and anthropogenic pollution.The extent of metal pollution was assessed by comparing the measured concentrations with those reported in the literature.Nine categories of PM2.5 pollution sources identified at the center of Shanghai show that the vehicle exhaust,emission of metallurgic industry and coal combustion are important.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10375075, 60321003, and 60438020, the National Key Basic Research and Development Programme of China under Grant No G1998010102, and the Knowledge Innovation Project of Chinese Academy of Sciences under Grant No KJCX2-SW-W14.
文摘Structures of membrane protein in solution are different from that in crystal phase. We present the primary results of small angle x-ray scattering （SAXS） resolved topological structures of a light harvesting antenna membrane protein complex LH2 from photosynthetic bacteria Rhodopseudomonas acidophila in detergent solution for the first time. Our results show that the elliptical shape of the LH2 complex in solution clearly deviates from its circular structure in crystal phase determined by x-ray diffraction. This result provides an insight into the structure and function interplay in LH2.
基金Supported by the National Natural Science Foundation of China under Grant No.10004014the synchrotron radiation experiments were carried out under Approval No.2001PF-03 of the Photon Factory.
文摘The high-pressure behaviour of the superconductor MgB_(2) with a hexagonal structure has been investigated by the in situ synchrotron radiation x-ray diffraction method under pressures up to 42.2 GPa in a diamond anvil cell. An abrupt decrease of about 7% in the unit cell volume of this material occurs in the pressure range of 26.3-30.2 GPa. A split of the Raman spectrum was also observed. The jump of the compression curve and Raman spectrum are ascribed to an isostructural transition in MgB_(2 ) at a pressure of 30.2 GPa.
文摘ALG-2(a gene product of PDCD6) is a 22-kD protein containing five serially repetitive EF-hand structures and belongs to the penta-EF-hand(PEF) family,including the subunits of typical calpains.ALG-2 is the most conserved protein among the PEF family members and its homologs are widely found in eukaryotes.X-ray crystal structures of various PEF proteins including ALG-2 have common features:presence of eightα-helices and dimer formation via paired EF5s that are positioned in anti-parallel orientation.ALG-2 forms a homodimer and a heterodimer with its closest paralog peflin.Like calmodulin,a well-known four-EF-hand protein,ALG-2 interacts with various proteins in a Ca2+-dependent fashion,but the binding motifs are completely different.With some exceptions,ALG-2-interacting proteins commonly contain Pro-rich regions,and ALG-2 recognizes at least two distinct Pro-containing motifs:PPYP(X) nYP(X,variable;n=4 in ALIX and PLSCR3) and PXPGF(represented by Sec31A) .A shorter alternatively spliced isoform,lacking two residues and designated ALG-2 GF122,does not bind ALIX but maintains binding capacity to Sec31A.X-ray crystal structural analyses have revealed that binding of calcium ions induces the configuration of the side chain of R125 so that it opens Pocket 1,which accepts PPYP,but Pocket 1 remains closed in the case of ALG-2 GF122.ALG-2 dimer has two ligand-binding sites,each in a monomer molecule,and appears to function as a Ca2+-dependent adaptor protein to either stabilize a preformed complex or to bridge two proteins on scaffolds in systems of the endosomal sorting complex required for transport(ESCRT) and ER-to-Golgi transport.
基金Supported by the National Natural Science Foundation of China (Grant No. 10775170)Major Project of Knowledge Innovation Program of Chinese Academy of Sciences (Grant No. KJCX3.SYW.N3)+2 种基金Key Project of Natural Science Foundation of Shanghai (Grant No. 08390513800)Project of Japan KEK, PF-PAC (Grant No. 2007G504)National Laboratory of BEPC (Grant No. VR-07004)
文摘In order to explore the mechanism of moss as air pollution biomonitor, the moss samples were exposed in a pollution site of Shanghai Institute of Steel Research (SISR) and a control site of Shanghai Institute of Applied Physics (SIAP) simultaneously for one month. The concentrations of trace elements in the micro areas of leaf and stem, as well as in the whole moss tissue, were determined using synchrotron radiation X-ray fluorescence (SRXRF) method. The distributions of some metal elements such as Pb, Cu, Fe, Ni, Mn, Zn, Ca and K in the leaf surface and the stem slice were obtained. The results showed that the metallic ions were not evenly distributed after adsorption. In particular, some elements of K, Ni, Fe, Pb, etc., were concentrated in the leaf apex and the intermediate rib. Under pollution condition, the excessive Pb was adsorbed and deposited in the leaf. It caused serious damage to plant growth and ultrastructure, also suppressed moss’ normal absorption to the nutritive elements of K, Ca, etc.
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.
基金National Natural Science Foundation of China (Grant No. 40572027)
文摘Chenguodaite, approved by IMA-CNMMN (2004-042a), was discovered in the Bunan quartz vein-type gold deposit in the gold district of East Shandong Peninsula. The mineral occurs in high grade Au-Ag-Cu ores, coexisting with galena, chalcopyrite, hessite, electrum, unnamed Ag6TeS2 and Ag16FeBiTe3S8, enclosed and replaced by native silver and acanthite. In the reflected light microscope, the mineral has light gray color, indistinguishable anistropism and hardness around 2―3. The color indices of chenguodaite relative to ICE C illuminator are: x=0.3027, y=0.3076, Y=25.78%, λd=474 nm, Pe=3.68%, similar to those of canfieldite. The average chemical composition from 16 microprobe analyses is Ag8.97Fe1.00Te1.99S4.04, idealized to Ag9FeTe2S4. The polycrystalline X-ray diffraction of chenguodaite by Gandolfi camera and synchrotron oscillation photography results in 67 reflections with the 12 strongest being (relative intensity in bracket): 6.742(69), 6.416(39), 5.951(33), 3.265(100), 2.981(24), 2.649(22), 2.25(24), 2.188(71), 2.142(22), 2.123(31), 2.044(23), 1.949(33), which are indexed to a primitive orthorhombic cell with a=12.769 (2) , b= 14.814(2), c= 16.233 (1) , V= 3070.63, Z = 9, Dcal.=6.85 g/cm3. The name is for the late Prof. Chen Guoda, a famous Chinese geologist and the founder of Diwa-Geodepression theory of tectonics.
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 50171077, 10004014 and 10032040).
文摘In-situ SR-XRD measurements revealed that the crystallization process in Zr41.2Ti13.8Cu12.5Ni10Be22.5 bulk metallic glass is significantly different from that in tradi-tional glasses. Subsequent heating at 10 GPa converts the sample from amorphous phase into the metastable fcc phase and then leads to the fcc phase back to the amorphous phase, indicating that there exists ’reversible’ phase transition phe-nomena in the material under high pressure and high tem-perature.
