Nitrogen-doped three-dimensional graphene(N-doped 3D-graphene)is a graphene derivative with excellent adsorption capacity,large specific surface area,high porosity,and optoelectronic properties.Herein,N-doped 3D-graph...Nitrogen-doped three-dimensional graphene(N-doped 3D-graphene)is a graphene derivative with excellent adsorption capacity,large specific surface area,high porosity,and optoelectronic properties.Herein,N-doped 3D-graphene/Si heterojunctions were grown in situ directly on silicon(Si)substrates via plasma-assisted chemical vapor deposition(PACVD),which is promising for surface-enhanced Raman scattering(SERS)substrates candidates.Combined analyses of theoretical simulation,incorporating N atoms in 3D-graphene are beneficial to increase the electronic state density of the system and enhance the charge transfer between the substrate and the target molecules.The enhancement of the optical and electric fields benefits from the stronger light-matter interaction improved by the natural nano-resonator structure of N-doped 3D-graphene.The as-prepared SERS substrates based on N-doped 3D-graphene/Si heterojunctions achieve ultra-low detection for various molecules:10^(-8)M for methylene blue(MB)and 10^(-9)M for crystal violet(CRV)with rhodamine(R6G)of 10^(10)M.In practical detected,10^(-8)M thiram was precisely detected in apple peel extract.The results indicate that N-doped 3D-graphene/Si heterojunctions based-SERS substrates have promising applications in low-concentration molecular detection and food safety.展开更多
Highly sensitive and uniform three-dimensional(3D)hybrid heterogeneous structures for use in surface-enhanced Raman scattering(SERS)experiments were fabricated by sequentially decorating high-quality,ultra-clean,graph...Highly sensitive and uniform three-dimensional(3D)hybrid heterogeneous structures for use in surface-enhanced Raman scattering(SERS)experiments were fabricated by sequentially decorating high-quality,ultra-clean,graphene quantum dots(GQDs)and Ag nanoparticles(Ag-NPs)onto 3D-graphene.Finite-difference time-domain calculations and scanning Kelvin probe microscopy were used to verify that the Ag-NPs/GQDs/3D-graphene system facilitates substantial electromagnetic enhancement(due to the occurrence of two kinds of"gaps"between the Ag-NPs that form 3D"hot spots")and additional chemical enhancement(in detecting someπ-conjugated molecules).The SERS mechanism was explored in further detail via experimental analysis and confirmed by performing theoretical calculations.The large surface area of the 3D substrate(due to the large specific surface areas of the GQDs and 3D-graphene)results in a better enrichment effect which helps produce lower detection limits.In particular,the detection limits obtained using the Ag-NPs/GQDs/3D-graphene platform can reach 10^(-11)M for rhodamine 6G,10^(-10)M for methylene blue and dopamine,and 10^(-7)M for tetramethylthiuram disulfide and methyl parathion in apple juice(these are superior to most of the results reported using graphene-based SERS substrates).In summary,the 3D-platform Ag-NPs/GQDs/3D-graphene/Si shows outstanding SERS performance.It therefore has excellent application prospects in biochemical molecular detection and food safety monitoring.展开更多
With the local major cultivar Leccino as the control,the fruit quality,yield and early maturing property of introduced olive cultivars( Koroneiki,Arbequina,Hojiblanca) from Spain were studied. The results showed that ...With the local major cultivar Leccino as the control,the fruit quality,yield and early maturing property of introduced olive cultivars( Koroneiki,Arbequina,Hojiblanca) from Spain were studied. The results showed that there were differences in fruit traits such as single fruit weight,ratio of flesh content,moisture content and oil content between different cultivars. The yield of early maturing property of the introduce cultivars were better than those of Leccino. The introduced varieties can fruit after 1-2 a,showing early maturity and high yield. This can provide a theoretical reference for the cultivation of olive in Longnan.展开更多
Carbon-based quantum dots(CQDs)have been shown to have promising application value in tumor diagnosis.Their use,however,is severely hindered by the complicated nature of the nanostructures in the CQDs.Furthermore,it s...Carbon-based quantum dots(CQDs)have been shown to have promising application value in tumor diagnosis.Their use,however,is severely hindered by the complicated nature of the nanostructures in the CQDs.Furthermore,it seems impossible to formulate the mechanisms involved using the inadequate theoretical frameworks that are currently available for CQDs.In this review,we re-consider the structure-property relationships of CQDs and summarize the current state of development of CQDs-based tumor diagnosis based on biological theories that are fully developed.The advantages and deficiencies of recent research on CQDs-based tumor diagnosis are thus explained in terms of the manifestation of nine essential changes in cell physiology.This review makes significant progress in addressing related problems encountered with other nanomaterials.展开更多
The development of ultra-sensitive methods for detecting anions is limited by their low charge to radius ratios, microenvironment sensitivity, and p H sensitivity. In this paper, a magnetic sensor is devised that expl...The development of ultra-sensitive methods for detecting anions is limited by their low charge to radius ratios, microenvironment sensitivity, and p H sensitivity. In this paper, a magnetic sensor is devised that exploits the controllable and selective coordination that occurs between a magnetic graphene quantum dot(GQD) and fluoride anion(F–). The sensor is used to measure the change in relaxation time of aqueous solutions of magnetic GQDs in the presence of F–using ultra-low-field(118 μT) nuclear magnetic resonance relaxometry. The method was optimized to produce a limit of detection of 10 nmol/L and then applied to quantitatively detect F–in domestic water samples. More importantly, the key factors responsible for the change in relaxation time of the magnetic GQDs in the presence of F–are revealed to be the selective coordination that occurs between the GQDs and F–as well as the localized polarization of the water protons. This striking finding is not only significant for the development of other magnetic probes for sensing anions but also has important ramifications for the design of contrast agents with enhanced relaxivity for use in magnetic resonance imaging.展开更多
As a two-dimensional carbon based semiconductor,C_(3)N acts as a promising material in many application areas.However,the basic physical properties such as Raman spectrum properties of C_(3)N is still not clear.In thi...As a two-dimensional carbon based semiconductor,C_(3)N acts as a promising material in many application areas.However,the basic physical properties such as Raman spectrum properties of C_(3)N is still not clear.In this paper,we clarify the Raman spectrum properties of multilayer C_(3)N.Moreover,the stacking driven Raman spectra change of multilayer C_(3)N is also discussed.展开更多
Arterioportal fistulas(APFs)are defined as vascular communications between the systemic arteries and portal circulation.APFs are classified as congenital or acquired,large or small,intrahepatic or extrahepatic,and tra...Arterioportal fistulas(APFs)are defined as vascular communications between the systemic arteries and portal circulation.APFs are classified as congenital or acquired,large or small,intrahepatic or extrahepatic,and traumatic or spontaneous.The consistent abnormal connection may result in severe presinusoidal portal hypertension,leading to gastrointestinal bleeding(GIB),ascites,elevated liver function enzymes,heart failure,diarrhea,and even pancreatitis or hematobilia in some unusual cases.Indeed,less than half reported cases have GIB,predominately caused by variceal rupture.Peptic ulcer bleeding has rarely been reported in the setting of APFs.Herein,we describe a case in which intrahepatic APF manifested as gastric ulcer bleeding,progressive portal thrombosis,and massive ascites,with these symptoms successfully relieved by endovascular treatment.展开更多
基金supported by the National Natural Science Foundation of China under Grant(No.62174093)the Natural Science Foundation of Ningbo under Grant(No.202003N4097)+5 种基金the support from the Beijing Institute of Technology Research Fund Program for Young Scholarsthe support from Guangdong Provincial Medical Science and Technology Research(A2019434)the support from Guangdong Provincial Key Laboratory of Computational Science and Material Design(2019B030301001)Fundamental Research Program of Shenzhen(JCYJ20190809174203802)National Natural Science Foundation of Guangdong Province(2022A1515110628)supported by Center for Computational Science and Engineering at Southern University of Science and Technology
文摘Nitrogen-doped three-dimensional graphene(N-doped 3D-graphene)is a graphene derivative with excellent adsorption capacity,large specific surface area,high porosity,and optoelectronic properties.Herein,N-doped 3D-graphene/Si heterojunctions were grown in situ directly on silicon(Si)substrates via plasma-assisted chemical vapor deposition(PACVD),which is promising for surface-enhanced Raman scattering(SERS)substrates candidates.Combined analyses of theoretical simulation,incorporating N atoms in 3D-graphene are beneficial to increase the electronic state density of the system and enhance the charge transfer between the substrate and the target molecules.The enhancement of the optical and electric fields benefits from the stronger light-matter interaction improved by the natural nano-resonator structure of N-doped 3D-graphene.The as-prepared SERS substrates based on N-doped 3D-graphene/Si heterojunctions achieve ultra-low detection for various molecules:10^(-8)M for methylene blue(MB)and 10^(-9)M for crystal violet(CRV)with rhodamine(R6G)of 10^(10)M.In practical detected,10^(-8)M thiram was precisely detected in apple peel extract.The results indicate that N-doped 3D-graphene/Si heterojunctions based-SERS substrates have promising applications in low-concentration molecular detection and food safety.
基金support provided by the National Natural Science Foundation of China under Grant(No.62174093)Guangdong Provincial Key Laboratory of Computational Science and Material Design(2019B030301001)+1 种基金Fundamental Research Program of Shenzhen(JCYJ20190809174203802)K.C.Wong Magna Fund in Ningbo University and Natural Science Foundation of Ningbo under Grant(No.202003 N4097).
文摘Highly sensitive and uniform three-dimensional(3D)hybrid heterogeneous structures for use in surface-enhanced Raman scattering(SERS)experiments were fabricated by sequentially decorating high-quality,ultra-clean,graphene quantum dots(GQDs)and Ag nanoparticles(Ag-NPs)onto 3D-graphene.Finite-difference time-domain calculations and scanning Kelvin probe microscopy were used to verify that the Ag-NPs/GQDs/3D-graphene system facilitates substantial electromagnetic enhancement(due to the occurrence of two kinds of"gaps"between the Ag-NPs that form 3D"hot spots")and additional chemical enhancement(in detecting someπ-conjugated molecules).The SERS mechanism was explored in further detail via experimental analysis and confirmed by performing theoretical calculations.The large surface area of the 3D substrate(due to the large specific surface areas of the GQDs and 3D-graphene)results in a better enrichment effect which helps produce lower detection limits.In particular,the detection limits obtained using the Ag-NPs/GQDs/3D-graphene platform can reach 10^(-11)M for rhodamine 6G,10^(-10)M for methylene blue and dopamine,and 10^(-7)M for tetramethylthiuram disulfide and methyl parathion in apple juice(these are superior to most of the results reported using graphene-based SERS substrates).In summary,the 3D-platform Ag-NPs/GQDs/3D-graphene/Si shows outstanding SERS performance.It therefore has excellent application prospects in biochemical molecular detection and food safety monitoring.
基金Supported by People's Livelihood Science and Technology Project of Gansu Province 2018(18CX3ZK038)Province-level Key Talents Project of Gansu Province(2018-42)Central Fiscal Forestry Science and Technology Demonstration and Extension Fund([2018]ZYTG3)
文摘With the local major cultivar Leccino as the control,the fruit quality,yield and early maturing property of introduced olive cultivars( Koroneiki,Arbequina,Hojiblanca) from Spain were studied. The results showed that there were differences in fruit traits such as single fruit weight,ratio of flesh content,moisture content and oil content between different cultivars. The yield of early maturing property of the introduce cultivars were better than those of Leccino. The introduced varieties can fruit after 1-2 a,showing early maturity and high yield. This can provide a theoretical reference for the cultivation of olive in Longnan.
基金supported by the Shanghai Science and Technology Committee(grant nos.21ZR1482800,23YF1455800)Shanghai Post-doctoral Excellence Program(2022675)+1 种基金the National Natural Science Foundation of China(grant no.62174093)the support from the Youth Innovation Promotion Association of Chinese Academy of Sciences,and the Xinweizhixing Project of SIMIT.
文摘Carbon-based quantum dots(CQDs)have been shown to have promising application value in tumor diagnosis.Their use,however,is severely hindered by the complicated nature of the nanostructures in the CQDs.Furthermore,it seems impossible to formulate the mechanisms involved using the inadequate theoretical frameworks that are currently available for CQDs.In this review,we re-consider the structure-property relationships of CQDs and summarize the current state of development of CQDs-based tumor diagnosis based on biological theories that are fully developed.The advantages and deficiencies of recent research on CQDs-based tumor diagnosis are thus explained in terms of the manifestation of nine essential changes in cell physiology.This review makes significant progress in addressing related problems encountered with other nanomaterials.
基金financially supported by the National Natural Science Foundation of China (Nos. 11874378, 11804353, and 11774368)the Science and Technology Commission of Shanghai Municipality (Nos. 19511107100, 19511107400)。
文摘The development of ultra-sensitive methods for detecting anions is limited by their low charge to radius ratios, microenvironment sensitivity, and p H sensitivity. In this paper, a magnetic sensor is devised that exploits the controllable and selective coordination that occurs between a magnetic graphene quantum dot(GQD) and fluoride anion(F–). The sensor is used to measure the change in relaxation time of aqueous solutions of magnetic GQDs in the presence of F–using ultra-low-field(118 μT) nuclear magnetic resonance relaxometry. The method was optimized to produce a limit of detection of 10 nmol/L and then applied to quantitatively detect F–in domestic water samples. More importantly, the key factors responsible for the change in relaxation time of the magnetic GQDs in the presence of F–are revealed to be the selective coordination that occurs between the GQDs and F–as well as the localized polarization of the water protons. This striking finding is not only significant for the development of other magnetic probes for sensing anions but also has important ramifications for the design of contrast agents with enhanced relaxivity for use in magnetic resonance imaging.
基金supported by The National Natural Science Foundation of China (Nos. 11804353 and 11774368)Shanghai Science and Technology Committee (No. 18511110600)
文摘As a two-dimensional carbon based semiconductor,C_(3)N acts as a promising material in many application areas.However,the basic physical properties such as Raman spectrum properties of C_(3)N is still not clear.In this paper,we clarify the Raman spectrum properties of multilayer C_(3)N.Moreover,the stacking driven Raman spectra change of multilayer C_(3)N is also discussed.
文摘Arterioportal fistulas(APFs)are defined as vascular communications between the systemic arteries and portal circulation.APFs are classified as congenital or acquired,large or small,intrahepatic or extrahepatic,and traumatic or spontaneous.The consistent abnormal connection may result in severe presinusoidal portal hypertension,leading to gastrointestinal bleeding(GIB),ascites,elevated liver function enzymes,heart failure,diarrhea,and even pancreatitis or hematobilia in some unusual cases.Indeed,less than half reported cases have GIB,predominately caused by variceal rupture.Peptic ulcer bleeding has rarely been reported in the setting of APFs.Herein,we describe a case in which intrahepatic APF manifested as gastric ulcer bleeding,progressive portal thrombosis,and massive ascites,with these symptoms successfully relieved by endovascular treatment.
