To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser...To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.展开更多
Cellulose and its derivatives are natural materials with high carbon contents, but it is challenging to convert their carbon into high value-added carbonaceous materials(e.g., graphene). Here, an approach to convert t...Cellulose and its derivatives are natural materials with high carbon contents, but it is challenging to convert their carbon into high value-added carbonaceous materials(e.g., graphene). Here, an approach to convert the carbon in cellulose into N, P co-doped porous graphene(LIG) materials via laser induction is proposed. Cellulose nanofibrils(CNFs), a cellulose derivative with high dispersion uniformity and abundant surface hydroxyl groups, were easily formed on a bulk substrate(thickness ≥5 mm) containing ammonium polyphosphate(APP). Then, a 10.6 μm CO2 laser was used to scribe for 1–5 passes on the CNFs/APP substrate under an ambient environment to produce N, P co-doped porous LIG. Upon increasing the number of laser scribing passes, the IG/IDof LIG first increased and then decreased, reaching a maximum of 1.68 at 4 passes. The good pore structure and low resistance also showed that 4 laser passes were ideal. Besides, the N, P co-doped LIG also showed excellent electrochemical performance, with a specific capacitance of 221.4 FF·g^(-1) and capacitance retention of 89.9%. This method exploits the advantages of nanocellulose and overcomes the difficulties associated with directly compounding cellulosic materials, providing a method for the further development of biomass nanomaterials.展开更多
hin films of ZnO were prepared using the double photobeams ultraviolet laserinduced-metallorganic chemical vapour deposition (MOCVD)technique. The struc-ture and transparent photoconductive properties of these films w...hin films of ZnO were prepared using the double photobeams ultraviolet laserinduced-metallorganic chemical vapour deposition (MOCVD)technique. The struc-ture and transparent photoconductive properties of these films were investigated us-ing X-ray diffraction (XRD) , reflecting electron diffraction (RED) .scanning elec-tron microscopy (SEM) and ultraviolet visible absorption spectrometry (UV) .Theexperiments showed that the technique produced superior quality films of polycrys-tal ZnO_(1-x) (the O-vacancies in the ZnO lattice) , and possessed higher depositionrate, lower growth temperature conipared with CVD or MOCVD technique and thethin films had far better transparent photoconductive properties than tliose grownby the conventional CVD or MOCVD technique.展开更多
An innovative application of laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to...An innovative application of laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap- proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain- less steel sheets served as research objects： 3 mm×l 300 mm hot-rolled stainless steel plate and 1 mm×l 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned （raster area -44 mm2 and 11 mm2） with a focused laser beam （wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ） in a laser abla- tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of 27A1＋, 44Ca＋, 47Ti-, 55Mn＋ and 56Fe＋ within an area of interest possible. One-dimensional （ID） content line distribution maps and two- dimensional （2D） contour maps for specific positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta- tistic segregation and content-frequency distribution.展开更多
Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in ...Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.展开更多
Nanoparticles(NPs)are versatile tools in various applications,particularly in the biomedical fields.To understand their behavior within biological systems,it is crucial to measure their distributions in vivo,especiall...Nanoparticles(NPs)are versatile tools in various applications,particularly in the biomedical fields.To understand their behavior within biological systems,it is crucial to measure their distributions in vivo,especially as they interact with the immune system and excretory organs,to ensure their efficacy,safety,and clearance.Here,we demonstrate the unique capabilities of laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)imaging for revealing the temporal redistribution of gold NPs(AuNPs)in key excretory organs.The quantitative and suborgan specific information available in LA-ICP-MS measurements indicate that positive AuNPs are more rapidly excreted through the hepatobiliary system of the liver than AuNPs having other surface charges.Using multielement image segmentation methods,we find that positive and zwitterionic AuNPs transition from the marginal zone of the spleen to the red pulp over time,indicating uptake by red pulp macrophages.In contrast,negative AuNPs redistribute more slowly,indicating different interactions with the immune system.Comparisons of high-resolution LA-ICP-MS images and fluorescence microscopy images on the same tissue sections reveal that positive AuNPs are excreted through the glomeruli of the kidney more effectively than are AuNPs with other charges.Overall,we demonstrate the power of LA-ICP-MS imaging for providing detailed information about AuNP fate at the suborgan level,which affords new insight into the interplay between surface chemistry and excretion pathways.展开更多
基金Projects(51471084,61475117)supported by the National Natural Science Foundation of ChinaProject(13ZCZDGX01109)supported by Tianjin Municipal Science and Technology Commission of ChinaProject(20122BBE500031)supported by the Key Technology Project of Jiangxi Province in China
文摘To select the proper composition and obtain an overall material?microstructure?property relationship for Cu?Fe alloy, theeffect of Fe content on microstructure and properties of Cu?Fe-based composite coatings by laser induction hybrid rapid claddingwas investigated. Microstructure characterization of the composite coatings was tested utilizing SEM, XRD and EDS. Microhardnessmeasurement was executed to evaluate the mechanical properties of the composite coatings. The results show that for low Fe content,the composite coating presents a feature that Fe-rich equiaxed dendrites are embedded in the Cu-rich matrix. With increasing Fecontent, the Fe-rich particles are dispersed in the Cu-rich matrix. With further increasing Fe content, large amounts of Cu-richparticles are homogeneously dispersed in the interdendrite of the Fe-rich matrix. Correspondingly, the average microhardness of thecomposite coatings increases gradually with the increase of Fe content and the microhardness of Cu14.5Fe83Si2C0.5 coating is muchtwice higher than that of the substrate.
基金supported by Beijing Zhongkebaice Technology Service Co.,Ltd.
文摘Cellulose and its derivatives are natural materials with high carbon contents, but it is challenging to convert their carbon into high value-added carbonaceous materials(e.g., graphene). Here, an approach to convert the carbon in cellulose into N, P co-doped porous graphene(LIG) materials via laser induction is proposed. Cellulose nanofibrils(CNFs), a cellulose derivative with high dispersion uniformity and abundant surface hydroxyl groups, were easily formed on a bulk substrate(thickness ≥5 mm) containing ammonium polyphosphate(APP). Then, a 10.6 μm CO2 laser was used to scribe for 1–5 passes on the CNFs/APP substrate under an ambient environment to produce N, P co-doped porous LIG. Upon increasing the number of laser scribing passes, the IG/IDof LIG first increased and then decreased, reaching a maximum of 1.68 at 4 passes. The good pore structure and low resistance also showed that 4 laser passes were ideal. Besides, the N, P co-doped LIG also showed excellent electrochemical performance, with a specific capacitance of 221.4 FF·g^(-1) and capacitance retention of 89.9%. This method exploits the advantages of nanocellulose and overcomes the difficulties associated with directly compounding cellulosic materials, providing a method for the further development of biomass nanomaterials.
文摘hin films of ZnO were prepared using the double photobeams ultraviolet laserinduced-metallorganic chemical vapour deposition (MOCVD)technique. The struc-ture and transparent photoconductive properties of these films were investigated us-ing X-ray diffraction (XRD) , reflecting electron diffraction (RED) .scanning elec-tron microscopy (SEM) and ultraviolet visible absorption spectrometry (UV) .Theexperiments showed that the technique produced superior quality films of polycrys-tal ZnO_(1-x) (the O-vacancies in the ZnO lattice) , and possessed higher depositionrate, lower growth temperature conipared with CVD or MOCVD technique and thethin films had far better transparent photoconductive properties than tliose grownby the conventional CVD or MOCVD technique.
基金Sponsored by National Major Instrument and Equipment Development Special Project of China(2011YQ14014710)
文摘An innovative application of laser ablation inductively coupled plasma mass spectrometry （LA-ICP-MS） technique in illustrating elemental distributions on stainless steel sheets was presented. The technique proved to be a systematic and accurate ap- proach in producing visual images or maps of elemental distributions at cross-sectional surface of a stainless steel sheet. Two stain- less steel sheets served as research objects： 3 mm×l 300 mm hot-rolled stainless steel plate and 1 mm×l 260 mm cold-rolled plate. The cross-sectional surfaces of the two samples at 1/4 position along the width direction were scanned （raster area -44 mm2 and 11 mm2） with a focused laser beam （wavelength 213 nm, diameter of laser crater 100 μm, and laser power 1.6 mJ） in a laser abla- tion chamber. The laser ablation system was coupled to a quadrupole ICP-MS, which made the detection of ion intensities of 27A1＋, 44Ca＋, 47Ti-, 55Mn＋ and 56Fe＋ within an area of interest possible. One-dimensional （ID） content line distribution maps and two- dimensional （2D） contour maps for specific positions or areas were plotted to indicate the element distribution of a target area with high accuracy. Statistic method was used to analyze the acquired data by calculating median contents, maximum segregation, sta- tistic segregation and content-frequency distribution.
基金Supported by the Key Research and Development Project of Guangdong Province(No.2020B1111510001)the National Natural Science Foundation of China(No.U2244224)+1 种基金the PI Project of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)(No.GML2020GD0802)the Guangdong Special Support Team Program(No.2019BT02H594)。
文摘Bivalve shell fossils,cemented by authigenic carbonates,are widely spread in the Haima cold seep,Qiongdongnan Basin of the South China Sea(SCS).In this study,we examined an element profile of Gigantidas platifrons in the Haima cold seeps at a water depth of 1381 m.Based on the scanning electron microscope(SEM)analyses,the prismatic layer and nacreous layer were identified,which are characterized by prismatic structure and stratified structure,respectively.In addition,the profile can be subdivided into two parts:altered and unaltered zones.Laser inductively coupled plasma mass spectrometry(LA-ICP-MS)mapping shows that the element concentrations of the altered zones were influenced by the authigenic carbonate rocks,whereas the element concentrations of unaltered zones remain stable.In-situ X-ray diffraction(XRD)analyses show that the mineral constituent of the prismatic layer is mainly composed of aragonite.Along with the growth profile,Mg/Ca ratios of unaltered zones have minor variations,ranging 0.72-0.97 mmol/mol(mean=0.87 mmol/mol),with estimated temperatures of 3.8-4.1℃,indicating that the temperature of the surrounding seawater remains constant and agree with the measured data of 3.9℃which was conducted by a conductivity-temperature-depth system(CTD).The minor variations of Ba/Ca ratios(0.01-0.06 mmol/mol;mean=0.04 mmol/mol)indicate a relatively stabilized salinity of the surrounding seawater.S/Ca ratios show large variations of 0.04-4.15 mmol/mol(mean=1.37 mmol/mol).S/Ca ratios have regular variations which generally correspond to the variations of the Mg/Ca ratios,highlighting that the S/Ca ratios of bivalve shells show the potential to reflect the growth rate of the Gigantides.However,further studies should be carried out on the understanding of the links between the S/Ca ratios and seepage intensity of cold-seep fluids.
基金supported by the National Science Foundation,Grant CHE-2108044.
文摘Nanoparticles(NPs)are versatile tools in various applications,particularly in the biomedical fields.To understand their behavior within biological systems,it is crucial to measure their distributions in vivo,especially as they interact with the immune system and excretory organs,to ensure their efficacy,safety,and clearance.Here,we demonstrate the unique capabilities of laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)imaging for revealing the temporal redistribution of gold NPs(AuNPs)in key excretory organs.The quantitative and suborgan specific information available in LA-ICP-MS measurements indicate that positive AuNPs are more rapidly excreted through the hepatobiliary system of the liver than AuNPs having other surface charges.Using multielement image segmentation methods,we find that positive and zwitterionic AuNPs transition from the marginal zone of the spleen to the red pulp over time,indicating uptake by red pulp macrophages.In contrast,negative AuNPs redistribute more slowly,indicating different interactions with the immune system.Comparisons of high-resolution LA-ICP-MS images and fluorescence microscopy images on the same tissue sections reveal that positive AuNPs are excreted through the glomeruli of the kidney more effectively than are AuNPs with other charges.Overall,we demonstrate the power of LA-ICP-MS imaging for providing detailed information about AuNP fate at the suborgan level,which affords new insight into the interplay between surface chemistry and excretion pathways.
