Sensitivity is crucially important for surface-enhanced Raman spectroscopy(SERS)application to detect trace-level polycyclic aromatic hydrocarbons(PAHs)in the seawater.In this study,a high sensitivity three-dimensiona...Sensitivity is crucially important for surface-enhanced Raman spectroscopy(SERS)application to detect trace-level polycyclic aromatic hydrocarbons(PAHs)in the seawater.In this study,a high sensitivity three-dimensional(3-D)SERS substrate composed with syringe filter,glycidyl methacrylate-ethylene dimethacrylate(GMA-EDMA)porous material and optimal parameters(57 nm,pH 13)gold nanoparticles(Au NPs)was developed for the detection of PAHs in water.The enhancement effect and repeatability of this 3-D substrate were also explored.The Raman intensity of pyrene using 3-D SERS substrate is about 8 times higher than that of substrate only using p H 13 gold colloid solution and about 12 times higher than that of substrate using natural Au NPs and GMA-EDMA porous material,which means both the pH 13 AuN Ps and the GMA-EDMA porous material are important factors for the sensitivity of this 3-D SERS substrate.Good repeatability of this optimal 3-D substrate was obtained.The relative standard deviation(RSD)is less than 8.66% on the same substrate and less than 3.69% on other different substrates.Four kinds of PAHs,i.e.,phenanthrene,pyrene,benzo(a)pyrene,benzo(k)fluoranthene and their mixture,were detected at the different concentrations.Their limits of detection(LODs)are 8.3×10^-10(phenanthrene),2.1×10^-10(pyrene),3.8×10^-10(benzo(a)pyrene)and 1.7×10^-10 mol L^-1(benzo(k)fluoranthene),respectively.In addition,these four PAHs were also detected by fluorescence spectroscopy to evaluate the sensitivity of SERS technology using this optimal 3-D SERS substrate.The results showed that the sensitivity of SERS based on the 3-D SERS substrate even using the portable Raman system was closed to that of fluorescence spectroscopy.Therefore,the SERS technology using this optimal 3-D substrate is expected to be an in-situ method for the detection of environmental PAHs.展开更多
In 2014, magnet division has contributed a lot of normal conducting and superconducting magnets to HIMMand ADS projects. Research efforts are also ongoing to develop the new technologies for future projects, such asfa...In 2014, magnet division has contributed a lot of normal conducting and superconducting magnets to HIMMand ADS projects. Research efforts are also ongoing to develop the new technologies for future projects, such asfast cycling superconducting dipole and Canted Cos-Theta(CCT) dipole for HIAF, magnetic lifting device for ADStarget system, superconducting magnets for SECRAL II ECRIS.展开更多
分析复合果蔬替代硝酸盐对发酵香肠中N-亚硝胺生成的影响,探究发酵香肠生产过程中复合果蔬取代部分硝酸盐的可能性。制备4组中式发酵香肠:阴性对照组(negative control group,NCG,空白组)、阳性对照组(positive control group,PCG)、芹...分析复合果蔬替代硝酸盐对发酵香肠中N-亚硝胺生成的影响,探究发酵香肠生产过程中复合果蔬取代部分硝酸盐的可能性。制备4组中式发酵香肠:阴性对照组(negative control group,NCG,空白组)、阳性对照组(positive control group,PCG)、芹菜樱桃组(celery and cherry group,CCG)、卷心菜番茄组(cabbage and tomato group,CTG),考察在发酵及成熟过程中亚硝酸盐、亚硝胺及生物胺含量的变化。结果表明:发酵过程中,果蔬发酵香肠(CCG和CTG)与PCG亚硝酸盐含量同样呈现先增加后降低趋势,但CTG峰值(65.52 mg/kg)显著低于PCG(105.31 mg/kg)。4组发酵香肠均能检出N-二乙基亚硝胺(N-nitrosodiethylamine,NDEA),而果蔬发酵香肠(CCG和CTG)在发酵后期NDEA含量(1.23μg/kg未检出)显著低于PCG(3.72μg/kg)。干燥成熟阶段,果蔬发酵香肠(CTG和CCG)亚硝酸盐残留量(36.45 mg/kg和47.97 mg/kg)显著高于NCG(24.49 mg/kg)和PCG(31.40 mg/kg),但在干燥3 d后下降至国家标准限量(30 mg/kg)以下。成品中总生物胺含量排序为NCG>PCG>CCG>CTG,CTG中未检出组胺和酪胺。各组样品中N-二甲基亚硝胺(N-nitrosodimethylamine,NDMA)(PCG除外)和NDEA含量均随干燥进程而逐渐增加,但是果蔬发酵香肠(CCG和CTG)在干燥结束时NDMA(0.16μg/kg和0.11μg/kg)和NDEA含量(4.33μg/kg和4.13μg/kg)低于NCG(1.73μg/kg和9.50μg/kg),与PCG(0μg/kg和4.74μg/kg)相当。实验表明复合果蔬浆替代部分硝酸盐,可降低中式发酵香肠的N-亚硝胺和生物胺含量。展开更多
基金supported by the National Natural Science Foundation of China (No. 41476081)the Major Research and Development Project in Shandong Province (Nos. 2016GSF115020, 2019GHY112027)the Shandong Provincial Natural Science Foundation (No. ZR2015DM007)
文摘Sensitivity is crucially important for surface-enhanced Raman spectroscopy(SERS)application to detect trace-level polycyclic aromatic hydrocarbons(PAHs)in the seawater.In this study,a high sensitivity three-dimensional(3-D)SERS substrate composed with syringe filter,glycidyl methacrylate-ethylene dimethacrylate(GMA-EDMA)porous material and optimal parameters(57 nm,pH 13)gold nanoparticles(Au NPs)was developed for the detection of PAHs in water.The enhancement effect and repeatability of this 3-D substrate were also explored.The Raman intensity of pyrene using 3-D SERS substrate is about 8 times higher than that of substrate only using p H 13 gold colloid solution and about 12 times higher than that of substrate using natural Au NPs and GMA-EDMA porous material,which means both the pH 13 AuN Ps and the GMA-EDMA porous material are important factors for the sensitivity of this 3-D SERS substrate.Good repeatability of this optimal 3-D substrate was obtained.The relative standard deviation(RSD)is less than 8.66% on the same substrate and less than 3.69% on other different substrates.Four kinds of PAHs,i.e.,phenanthrene,pyrene,benzo(a)pyrene,benzo(k)fluoranthene and their mixture,were detected at the different concentrations.Their limits of detection(LODs)are 8.3×10^-10(phenanthrene),2.1×10^-10(pyrene),3.8×10^-10(benzo(a)pyrene)and 1.7×10^-10 mol L^-1(benzo(k)fluoranthene),respectively.In addition,these four PAHs were also detected by fluorescence spectroscopy to evaluate the sensitivity of SERS technology using this optimal 3-D SERS substrate.The results showed that the sensitivity of SERS based on the 3-D SERS substrate even using the portable Raman system was closed to that of fluorescence spectroscopy.Therefore,the SERS technology using this optimal 3-D substrate is expected to be an in-situ method for the detection of environmental PAHs.
文摘In 2014, magnet division has contributed a lot of normal conducting and superconducting magnets to HIMMand ADS projects. Research efforts are also ongoing to develop the new technologies for future projects, such asfast cycling superconducting dipole and Canted Cos-Theta(CCT) dipole for HIAF, magnetic lifting device for ADStarget system, superconducting magnets for SECRAL II ECRIS.
文摘分析复合果蔬替代硝酸盐对发酵香肠中N-亚硝胺生成的影响,探究发酵香肠生产过程中复合果蔬取代部分硝酸盐的可能性。制备4组中式发酵香肠:阴性对照组(negative control group,NCG,空白组)、阳性对照组(positive control group,PCG)、芹菜樱桃组(celery and cherry group,CCG)、卷心菜番茄组(cabbage and tomato group,CTG),考察在发酵及成熟过程中亚硝酸盐、亚硝胺及生物胺含量的变化。结果表明:发酵过程中,果蔬发酵香肠(CCG和CTG)与PCG亚硝酸盐含量同样呈现先增加后降低趋势,但CTG峰值(65.52 mg/kg)显著低于PCG(105.31 mg/kg)。4组发酵香肠均能检出N-二乙基亚硝胺(N-nitrosodiethylamine,NDEA),而果蔬发酵香肠(CCG和CTG)在发酵后期NDEA含量(1.23μg/kg未检出)显著低于PCG(3.72μg/kg)。干燥成熟阶段,果蔬发酵香肠(CTG和CCG)亚硝酸盐残留量(36.45 mg/kg和47.97 mg/kg)显著高于NCG(24.49 mg/kg)和PCG(31.40 mg/kg),但在干燥3 d后下降至国家标准限量(30 mg/kg)以下。成品中总生物胺含量排序为NCG>PCG>CCG>CTG,CTG中未检出组胺和酪胺。各组样品中N-二甲基亚硝胺(N-nitrosodimethylamine,NDMA)(PCG除外)和NDEA含量均随干燥进程而逐渐增加,但是果蔬发酵香肠(CCG和CTG)在干燥结束时NDMA(0.16μg/kg和0.11μg/kg)和NDEA含量(4.33μg/kg和4.13μg/kg)低于NCG(1.73μg/kg和9.50μg/kg),与PCG(0μg/kg和4.74μg/kg)相当。实验表明复合果蔬浆替代部分硝酸盐,可降低中式发酵香肠的N-亚硝胺和生物胺含量。
