A new paradigm for ship detection in polarimetric synthetic aperture radar(Pol-SAR)image is presented.We firstly utilize the scattering similarity parameters to investigate the differences of scattering mechanism betw...A new paradigm for ship detection in polarimetric synthetic aperture radar(Pol-SAR)image is presented.We firstly utilize the scattering similarity parameters to investigate the differences of scattering mechanism between ships and sea clutter.Based on these differences,we propose a novel ship detection metric,denoted as the scattering similarity based metric(SSM),to conduct ship detection task.The distribution model of SSM metric is investigated and modeled by kernel density estimation(KDE).Based on the statistical distribution,an adaptive constant false alarm rate(CFAR)detection scheme is implemented.We compare the proposed SSM with two classic polarimetric metrics,i.e.,the polarimetric cross-entropy(PCE)and the reflection symmetry metric(RSM).The experimental results conducted on C-band RADARSAT-2 Pol-SAR data demonstrate the feasibility and advantage of the proposed SSM metric both in sea clutter modeling and in ship detection.展开更多
We present a silicon slot waveguide with metallic gratings embedded on the silicon surface in the slot region. The dependence of the optical coupling between two silicon wires on the width of the metal gap and the slo...We present a silicon slot waveguide with metallic gratings embedded on the silicon surface in the slot region. The dependence of the optical coupling between two silicon wires on the width of the metal gap and the slot size are studied in detail. The results show that the optical field in the slot region with metallic gratings is significantly enhanced compared with the traditional slot waveguide due to the surface plasmon polaritons coupling on metallic gratings. The extraordinary optical confinement is attributed to the low effective dielectric constant of metallic gratings. The effective dielectric constant decreases with the increasing wavelength, and reaches the minimum when the width of the metal gap is about 0.01 times the wavelength.展开更多
Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody...Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody and the development of an indirect competitive biotin-streptavidin-amplified-based enzyme-linked immunosorbent assay（BA-ELISA） that can sensitively and specifically detect kanamycin residues in milk and honey. The immtmogen and coating antigen were synthesized by covalently linking kanamycin to carrier proteins using the carbodiimide method. The anti-kanamycin polyclonal antibodies were obtained from immunized rabbits. The key assay parameters were investigated and optimized. The results show that under optimum conditions, the limit of detection for kanamycin is 0.07 ng/mL and the ICs0 is 6.48 ng/mL. Cross-reactivity values of the antibody with four kanamycin analogues are all 〈1%. Trace amounts of kanamycin in milk and honey samples can be detected by this novel BA-ELISA method successfully with satisfactory recoveries of 91.0%-103.3%. The developed protocol was also validated against liquid chromatography-mass spectrometry, returning a significant correlation. These results indicate that BA-ELISA is a viable option for monitoring kanamycin residues in milk and honey.展开更多
In this study, we report a novel and facile autoclave strategy for synthesis of near-infrared （NIR） CulnS2 QDs by employing glutathione （GSH） as capping ligand and stabilizer in aqueous media under 100 ~C. Various...In this study, we report a novel and facile autoclave strategy for synthesis of near-infrared （NIR） CulnS2 QDs by employing glutathione （GSH） as capping ligand and stabilizer in aqueous media under 100 ~C. Various experi- mental parameters including the ratio of precursors, reaction time, reaction temperature, pH effect and stability have been systematically studied. The QDs were characterized by X-ray diffraction （XRD）, transmission electron micro- scope （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The as-synthesized NIR QDs exhibited low cytotoxicity and maintained excellent cell viability even up to 100 gg/mL. After bioconjugation with Arg-Gly-Asp （RGD） peptide, the obtained CulnS2-RGD QDs have demonstrated high targeting ability with good fluorescence cell imaging performance.展开更多
A novel 2,6-dimethyl-b-CD bonded and silica based HPLC chiral stationary phase（CSP） was prepared.The diphenylmethane diisocyanate（MDI） was applied for the first time in the immobilization of 2,6-dimethyl-b-CD onto...A novel 2,6-dimethyl-b-CD bonded and silica based HPLC chiral stationary phase（CSP） was prepared.The diphenylmethane diisocyanate（MDI） was applied for the first time in the immobilization of 2,6-dimethyl-b-CD onto the surface of aminized silica gel under mild conditions. The composite materials obtained were used as the CSP for chiral separation processes and this kind of CSP exhibits good enantioselectivity for a variety of chiral compounds under reversed-phase conditions.展开更多
Nanomaterial-based artificial enzymes（nanozymes） have shown great potential for application in colori- metric sensing. In this paper, the nanocomposites of CeO2 and reduced graphene oxide（rCK）） were fabricated vi...Nanomaterial-based artificial enzymes（nanozymes） have shown great potential for application in colori- metric sensing. In this paper, the nanocomposites of CeO2 and reduced graphene oxide（rCK）） were fabricated via a one-pot hydrothermal process, in which CeO2 nanoparticles were well anchored on the surface of rGO. The prepared CeO2/rGO nanocomposites exhibited excellent catalytic activity for the oxidation of 3,3＇,5,5＇-tetramethylbenzidine（TMB） in the presence of 02. Compared with the individual CeO2 nanoparticles, the nanocomposites had a higher affinity and adsorptivity towards the substrate TMB, which was due to the combination of rGO. In addi- tion, based on the oxidase-like activity of CeO2/rGO nanocomposites, a facile and sensitive colormetric sensor for ascorbic acid（AA） was investigated. The detection limit of AA was low（0.15μmol/L） and the linear detection range was between 0.5μmol/L and 40μmol/L. Fttrthermore, the colorimetric system was used for the detection of AA in medicine and food analysis, such as tablets, beverage and milk powder.展开更多
基金The National Natural Science Foundation of China under contract No.61471024the National Marine Technology Program for Public Welfare under contract No.201505002。
文摘A new paradigm for ship detection in polarimetric synthetic aperture radar(Pol-SAR)image is presented.We firstly utilize the scattering similarity parameters to investigate the differences of scattering mechanism between ships and sea clutter.Based on these differences,we propose a novel ship detection metric,denoted as the scattering similarity based metric(SSM),to conduct ship detection task.The distribution model of SSM metric is investigated and modeled by kernel density estimation(KDE).Based on the statistical distribution,an adaptive constant false alarm rate(CFAR)detection scheme is implemented.We compare the proposed SSM with two classic polarimetric metrics,i.e.,the polarimetric cross-entropy(PCE)and the reflection symmetry metric(RSM).The experimental results conducted on C-band RADARSAT-2 Pol-SAR data demonstrate the feasibility and advantage of the proposed SSM metric both in sea clutter modeling and in ship detection.
基金Supported by the Key Grant Project of the Ministry of Education of China under Grant No 313007
文摘We present a silicon slot waveguide with metallic gratings embedded on the silicon surface in the slot region. The dependence of the optical coupling between two silicon wires on the width of the metal gap and the slot size are studied in detail. The results show that the optical field in the slot region with metallic gratings is significantly enhanced compared with the traditional slot waveguide due to the surface plasmon polaritons coupling on metallic gratings. The extraordinary optical confinement is attributed to the low effective dielectric constant of metallic gratings. The effective dielectric constant decreases with the increasing wavelength, and reaches the minimum when the width of the metal gap is about 0.01 times the wavelength.
基金Supported by the National Natural Science Foundation of China（No.21675008）, the Natural Science Foundation of Beijing, China（No.2132048） and the Fundamental Research Funds for the Central Universities, China（No.JDl 516）.
文摘Kanamycin is an aminoglycoside antibiotic used increasingly in human and veterinary medicine. However, kanamycin residues in food can cause serious side effects, Here we reported the preparation of polyclonal antibody and the development of an indirect competitive biotin-streptavidin-amplified-based enzyme-linked immunosorbent assay（BA-ELISA） that can sensitively and specifically detect kanamycin residues in milk and honey. The immtmogen and coating antigen were synthesized by covalently linking kanamycin to carrier proteins using the carbodiimide method. The anti-kanamycin polyclonal antibodies were obtained from immunized rabbits. The key assay parameters were investigated and optimized. The results show that under optimum conditions, the limit of detection for kanamycin is 0.07 ng/mL and the ICs0 is 6.48 ng/mL. Cross-reactivity values of the antibody with four kanamycin analogues are all 〈1%. Trace amounts of kanamycin in milk and honey samples can be detected by this novel BA-ELISA method successfully with satisfactory recoveries of 91.0%-103.3%. The developed protocol was also validated against liquid chromatography-mass spectrometry, returning a significant correlation. These results indicate that BA-ELISA is a viable option for monitoring kanamycin residues in milk and honey.
文摘In this study, we report a novel and facile autoclave strategy for synthesis of near-infrared （NIR） CulnS2 QDs by employing glutathione （GSH） as capping ligand and stabilizer in aqueous media under 100 ~C. Various experi- mental parameters including the ratio of precursors, reaction time, reaction temperature, pH effect and stability have been systematically studied. The QDs were characterized by X-ray diffraction （XRD）, transmission electron micro- scope （TEM）, and Fourier transform infrared spectroscopy （FT-IR）. The as-synthesized NIR QDs exhibited low cytotoxicity and maintained excellent cell viability even up to 100 gg/mL. After bioconjugation with Arg-Gly-Asp （RGD） peptide, the obtained CulnS2-RGD QDs have demonstrated high targeting ability with good fluorescence cell imaging performance.
文摘A novel 2,6-dimethyl-b-CD bonded and silica based HPLC chiral stationary phase（CSP） was prepared.The diphenylmethane diisocyanate（MDI） was applied for the first time in the immobilization of 2,6-dimethyl-b-CD onto the surface of aminized silica gel under mild conditions. The composite materials obtained were used as the CSP for chiral separation processes and this kind of CSP exhibits good enantioselectivity for a variety of chiral compounds under reversed-phase conditions.
基金Supported by the National Natural Science Foundation of China（No.21675008） and the Fundamental Research Funds for the Central Universities of China（No.JD1516）.
文摘Nanomaterial-based artificial enzymes（nanozymes） have shown great potential for application in colori- metric sensing. In this paper, the nanocomposites of CeO2 and reduced graphene oxide（rCK）） were fabricated via a one-pot hydrothermal process, in which CeO2 nanoparticles were well anchored on the surface of rGO. The prepared CeO2/rGO nanocomposites exhibited excellent catalytic activity for the oxidation of 3,3＇,5,5＇-tetramethylbenzidine（TMB） in the presence of 02. Compared with the individual CeO2 nanoparticles, the nanocomposites had a higher affinity and adsorptivity towards the substrate TMB, which was due to the combination of rGO. In addi- tion, based on the oxidase-like activity of CeO2/rGO nanocomposites, a facile and sensitive colormetric sensor for ascorbic acid（AA） was investigated. The detection limit of AA was low（0.15μmol/L） and the linear detection range was between 0.5μmol/L and 40μmol/L. Fttrthermore, the colorimetric system was used for the detection of AA in medicine and food analysis, such as tablets, beverage and milk powder.
基金supported by the National Natural Science Foundation of China(21475007 and 21675009)the Fundamental Research Funds for Central Universities(buctrc201507 and buctrc201608)the support from the "Public Hatching Platform for Recruited Talents of BUCT"
基金supported by the National Natural Science Foundation of China(21475007,21275015 and 21505003)the Fundamental Research Funds for the Central Universities(YS1406,buctrc201507 and buctrc201608)+1 种基金the“Innovation and Promotion Project of Beijing University of Chemical Technology”,the“Public Hatching Platform for Recruited Talents of Beijing University of Chemical Technology,the High-Level Faculty Program of Beijing University of Chemical Technology(buctrc201325)BUCT Fund for Disciplines Construction and Development(XK1526)
基金supported in part by the National Natural Science Foundation of China (21475007 and 21675009)the Fundamental Research Funds for the Central Universities (buctrc201608 and buctrc201720)the support from the “Public Hatching Platform for Recruited Talents of Beijing University of Chemical Technology”
