6 research outputs found

    Optical System for Asymmetrical Crossed Czerny-Turner Raman Spectrometer with High Luminous Flux

    Get PDF
    为克服分立式便携拉曼光谱仪光通量低的缺点,设计了一种集拉曼探头光路与分光系统于一体的光学系统。探头光路采用大数值孔径的非球面透镜实现样品的有效激发和信号的高效收集,通过胶合透镜组缩小会聚光路尺寸、消除轴向色差。分光系统基于交叉非对称Czerny-Turner结构,为获得期望的光谱分辨率和光谱范围,建立了分光系统光谱分辨率及光谱范围与交叉非对称Czerny-Turner结构参数的关系。由测得的汞灯谱图可知,分光系统的光谱分辨率优于6 cm~(-1)(0.37 nm),光谱范围为790~950 nm(200~2000 cm~(-1))。将设计的光学系统对CCL4进行测试,实验结果表明在相同积分时间内由这种整体式的光学系统检测到的CCL4光谱谱峰强度是用商业探头通过光纤连接分光系统检测到的近3倍,验证了光学系统设计的合理性。To overcome the low luminous flux in separated portable Raman spectrometer, an optical system embodies the probe of Raman spectrometer and monochromator is designed. An aspherical lens with high numerical aperture is used to obtain the effective excitation of sample and the efficient collection of signal in the optical system of the probe. A cemented lens group is used to minish the size of converging path and eliminate chromatic aberration.The monochromator is based on asymmetrical crossed Czerny-Turner structure. For the purpose of achieving desired spectrum resolution and spectrum range, the relationship between the spectrum resolution and spectrum range of the monochromator and the structural parameters of the asymmetrical crossed Czerny-Turner system is established. According to the tested spectrogram of mercury lamp, the spectrum resolution of the monochromator is better than 6 cm~(-1)(0.37 nm), and spectrum range is 790~950 nm(200~2000 cm~(-1)). A sample of CCL4 is introduced to examine the performance of the optical system, the experimented results demonstrate that the peak intensity of spectrogram of CCL4 measured by this incorporative optical system is almost three times as high as that using a commercial probe couples to the monochromator, which verifies the rationality of the design of the optical system.国家自然科学基金(21503171);; 中央高校基本科研业务费项目(20720150091、20720150094);; 福建省高端装备制造协同创新中心资

    Design of Rapid Detection System for Urotropine in Food Based on SERS

    No full text
    基于表面增强拉曼光谱技术(surface enhanced Raman; spectroscopy,SERS),研制出对食品中乌洛托品进行现场快速分析检测的系统。检测系统由多功能前处理模块、拉曼光学模块、嵌入式主控模块; 三部分组成,实现了待测样品的前处理,拉曼光谱数据的产生、收集、传输与处理。其中,多功能前处理模块将化学实验中经常用到的离心、超声、挥发三种功能集; 于一体,精简了前处理实验中需要用到的设备;拉曼光学模块采用探头光路与分光系统合为一体的整体式设计,并在探头光路中使用数值孔径为0.6的非球面透镜; ,同时利用交叉非对称Czerny-Turner结构对分光系统进行了设计;嵌入式主控模块采用自主研发的FPGA+; ARM双核心主控电路,配合CCD的制冷电路与驱动电路,搭载muC/OS-Ⅲ操作系统,实现了对CCD上拉曼光谱数据的采集、传输与处理。利用柠檬酸钠; 制备纳米金(liquid colloidal gold; nanoparticle,LCP-1)作为增强试剂对乌洛托品进行检测,将乌洛托品的拉曼特征峰选取在1 047; cm~(-1)处,对乌洛托品标准品和含有乌洛托品的腐竹与米粉样品进行检测实验,实验结果表明所设计的检测系统可以实现对乌洛托品的准确识别,对乌洛托; 品标准品的检测限可达0.01 mg·L~(-1),对腐竹和米粉样品中乌洛托品的检出限可达0.5 mg· L~(-1),检测时间小于20; min,实现了食品中乌洛托品的现场快速检测。Based on surface enhanced Raman spectroscopy (SERS) technology, the detection system for rapid fild determination of urotropine in food is proposed. The detecting system consists of multifunctional pretreating module, Roman optical module and embedded master control module. It completed the pretreatment of sample, the generation, collection and transmission of the Raman spectral data. The multifunctional pretreating module integrate centrifuge, ultrasound and volatile functions all together, reducing the equipments used in the pretreatment experiment. Besides, it is portable and convenient for operation. The Roman optical module we designed embodies the probe of Raman spectrometer and monochromator, and the numerical aperture of the aspherical lens we used in the optical system of the probe was 0. 6. Besides, the monochromator was designed based on Asymmetrical crossed Czerny-Turner structure. The hardware part of the embedded master control module is made up of ARM and FPGA, and its peripheral circuits. The software part of the module is made up of real time operation system mu C/OS-HE graphics library emWin, file system FatFs and various types of equipment components. Thus, accomplished the collection, transmission and calculation of the Raman spectral data from CCD. The liquid colloidal gold nanoparticle (LCP-1) was used in the detection experiments of urotropine, while the characteristic peaks at 1 047 cm(-1) was chosen as the identity infoiniation of urotropine. The result of detection experiments shows that the system has the ability to identify the urotropine accurately, the detection limit of urotropine standards was 0. 01 mg . L-1, with detection limit of urotropine in yuba and rice-noodle was 0. 5 mg . L-1. Besides, the testing time was less than 20 minutes, which meets the requirements for rapid field determination of urotropine in food.国家自然科学基金项目(21503171)资

    杜鹃花菌根真菌454焦磷酸测序的样品制备

    No full text
    454焦磷酸测序已成为真菌群落结构研究的常用手段,文中对454焦磷酸测序的Barcoded PCR扩增中的模板质量浓度、Mg2+和引物浓度等反应条件进行了优化,并对扩增所得产物的特异性进行了鉴定;同时就不同Taq酶对测序结果的影响进行了讨论。结果表明:DNA模板经适度稀释能显著提高反应效率;Mg2+及引物浓度对扩增反应效率有影响,建议上下游引物浓度均为0.1μmol·L-1,Mg2+浓度可不做调整;使用特异性好、活性较强的Taq酶对保证扩增产物的真菌特异性至关重要,建议选用热启动Taq酶

    β-D-吡喃葡萄糖苷类香料前体的合成及表征

    No full text
    为了开发热稳定型香原料,由改进的银盐法合成了香叶基-β-D-吡喃葡萄糖苷、顺-3-己烯基-β-D-吡喃葡萄糖苷、薄荷基-β-D-吡喃葡萄糖苷,并与相转移法、路易斯酸催化法进行了比较,以香叶基-β-D-吡喃葡萄糖苷的合成为例,制备高效催化剂,探讨了催化剂、温度、时间等对糖苷化反应产率的影响,优化后收率为51%。以TLC、HPLC监控反应进程,采用IR、LC/MS、^1H-NMR、^13CNMR等进行了结构鉴定,对醇类香料的糖苷化反应进行了研究

    β-D-吡喃葡萄糖苷类香料前体的合成及表征

    No full text
    为了开发热稳定型香原料,由改进的银盐法合成了香叶基-β-D-吡喃葡萄糖苷、顺-3-己烯基-β-D-吡喃葡萄糖苷、薄荷基-β-D-吡喃葡萄糖苷,并与相转移法、路易斯酸催化法进行了比较,以香叶基-β-D-吡喃葡萄糖苷的合成为例,制备高效催化剂,探讨了催化剂、温度、时间等对糖苷化反应产率的影响,优化后收率为51%。以TLC、HPLC监控反应进程,采用IR、LC/MS、^1H-NMR、^13CNMR等进行了结构鉴定,对醇类香料的糖苷化反应进行了研究
    corecore