A Fast Baseline Correction Method for Raman Spectroscopy Based on Comparison

拉曼光谱成像技术是基于拉曼散射效应所开发的一项现代检测技术,在现代生产、科学研究过程中使用非常广泛。拉曼光谱信号受荧光效应和仪器等方面的影响,往; 往会产生基线漂移,严重影响对信号特征的进一步提取。因此,必须对拉曼光谱信号进行基线校正。传统的基线校正方法,只针对单一光谱信号,计算量较大,在处; 理由大量拉曼信号组成的成像数据时,耗时较长且效果不佳。该文提出一种基于临近比较的快速基线校正方法,根据在相同背景下采集的光谱之间的相关性,实现快; 速基线校正,提高了拉曼成像数据的处理速度。Raman imaging is a kind of modern testing technology based on Raman; scattering,which has been widely applied in manufacturing and scientific; research. However, due to the fluorescent effect and instruments drift,; the baseline shift could easily occur, which has a strong impact on the; feature extraction of the Raman signals. Therefore,the baseline; correction is necessary and inevitable in the signal processing of Raman; spectra. The traditional baseline correction methods can only correct; the Raman spectrum one by one, so once a large amount of Raman imaging; signals have to be processed, the processing time is too long to accept.; In this paper, the baseline correction base on comparison which; considers the correlation between the Raman spectra and the same; background is proposed to realize the fast baseline correction and; improve the processing speed of Raman imaging data

军人心理应激研究及其进展

综述应激的基本模式 ,军人心理应激反应的类型、应对及研究进展。分析影响军人心理健康的主要因素 ,提出军人心理应激管理应注意从个体水平和组织水平两方面进行

Design of Raman spectroscopy measurement system based on shifted excitation method using two laser diodes with different wavelengths

拉曼光谱检测常常受到荧光干扰,而移频激发拉曼差分光谱法(SERDS)是一种有效抑制拉曼光谱荧光背景的方法。基于该方法,采用两个波长相近、基于体布拉格光栅技术的固定波长激光器,设计了一套拉曼光谱测试系统。通过控制激光器的功率和温度,保证了输出波长的稳定性。采用高灵敏度的薄型背照式面阵CCD,设计了光谱数据采集光路和电路。同时,在软件上实现了差分光谱的三种重构算法,即简单积分算法、带数值插值的简单积分算法和多重约束解卷积算法。在实验中,利用文中系统对强荧光背景的某品牌香油进行了拉曼光谱测量,分别采用这三种算法处理差分光谱进行光谱重构,并对比了重构效果。实验结果表明,设计的系统能够有效抑制荧光对拉曼光谱检测的影响。Raman detection is often disturbed by fluorescence background, while Shifted Excitation Raman Difference Spectroscopy(SERDS)is an effective method for fluorescent suppression on Raman spectroscopy.Based on this method, a Raman spectroscopy measurement system was designed using two closely space fixed-wavelength laser diodes stabilized with the Volume Bragg Gratings. The output wavelength of laser diodes was stabilized by manipulating their power and temperature. The light path and circuit of spectral data acquisition were designed with back-thinned area array CCD with high sensitivity. Besides, the three different reconstruction algorithms of the difference spectrum, namely simple integration algorithm, simple integration with data interpolation algorithm and multiple energy constraint iterative deconvolution algorithm could be realized through software of this system. The Raman spectra of sesame oil of some brand in the presence of a highly fluorescent were measured with this system and then the spectra reconstructed with three different algorithms to process the difference spectrum respectively were compared.Experimental results show that the system designed in this paper can effectively reject the effect of fluorescence to the Raman spectroscopy measurement.国家重大科学仪器设备开发专项(2011YQ03012417

Design of Raman spectroscopy measurement system based on SHINERS

基于壳层隔绝纳米粒子增强技术,开发了一种新型的等离激元拉曼光谱测试系统,该系统能够有效地提高被测物质的拉曼反射信号强度。壳层隔绝纳米粒子增强技术采用包裹了极薄的二氧化硅或者氧化铝壳层的单层金纳米粒子,能够产生较强的表面增强效应。整个测试系统的硬件部分主要包括双处理器(ArM和dSP)主控板、半导体激光光源、光谱仪、光纤探头和粒子施加装置;软件部分能够自动获取被测物质的拉曼谱图。这里,粒子施加装置用于自动地将壳层隔绝纳米粒子施加到被测样本中。在实验中,将测试系统用于检测食品违禁添加物三聚氰胺和孔雀石绿,以验证壳层隔绝纳米粒子增强拉曼光谱技术。实验结果表明,该测试系统具有较高的测试灵敏度和较短的测试时间,广泛地适用于食品安全中痕量物质快速检测。In this paper,the Raman spectroscopy mea surement system was presented,where Shell isolated Nanoparticle Enhanced Raman Spectroscopy(SHINERS) technique was used to amplify the Raman signal.This technique used gold nanoparticles coated with a thin,uniform,fully enclosed and optically transparent shell of silica or alumina so that the gold core generated a large surface enhancement.Based on this technique,the hardware framework of this measurement system was mainly composed of double central control chips(ARM and DSP),a laser diode source,a spectrometer,a fiber probe and a nanoparticle giving device;and the software of this system can achieve the Raman spectrogram automatically.The giving device was used to spread the SHINERS particle into the samples for improving automation.The experiments were performed to detect the food added melamine and malachite green for verifying the effectiveness of SHINERS.The results show that the measurement system is of high detection sensitivity and short testing time effectively,which can be widely adopted in the rapid detection of trace substances in food safety.国家重大科学仪器设备开发专项(2011YQ03012417

Thermal performance testing for high power light-emitting diode based on voltage-current characteristics with pulse injection

热学特性是影响功率型lEd光学和电学特性的主要因素之一,设计了一套基于脉冲式u-I特性的功率型lEd热学特性测试系统,可以测试在不同结温下lEd工作电流与正向电压的关系,从而获得lEd的热学特性参数。该系统通过产生窄脉冲电流来驱动lEd,对其峰值时的电压电流进行采样,同时控制和采集lEd的热沉温度,从而获得不同温度下lEd的u-I特性曲线。与其他u-I测试系统相比,文中采用了窄脉冲(1μS)工作电流,lEd器件Pn结区处于发热与散热的交替过程,不会造成大的热积累,大大提高了测量精度。实验中,对某功率型lEd进行了测试,获得了该器件的电压、电流和结温特性曲线,并利用b样条建立该器件的u-I-T模型,进而实现了对其结温的实时在线检测。Thermal performance is one of the main factors which affect the optical and electrical performance of high power LED.The thermal performance testing system for high power LEDs based on voltage-current characteristics with pulse injection was designed in this paper, which can test the relationship between the operating current and forward voltage of LED under different junction temperatures, thereby obtaining LED thermal characteristics parameters.The system worked by generating a controlled narrow pulse current to drive the LED, and sampling the peaks of voltage and current of LEDs with LED heat sink temperature control and acquisition, thereby obtaining the voltage-current characteristic curve in different junction temperatures.Compared with other voltage-current testing systems, the designed system adapts the narrow pulse duty cycle(1 μs), so the PN junction of LED devices is always in the process of alternately heating and cooling, which can avoid large heat accumulation and greatly improve the accuracy of measurement.In the experiment, a power LED device was tested by the system and the voltage-current-temperature curve was obtained.Then the B-spline based U-I-T model of the LED was established, so the real-time online detection of LED device was achieved.国家自然科学基金(61102030

军人心理应激研究及其进展

综述应激的基本模式 ,军人心理应激反应的类型、应对及研究进展。分析影响军人心理健康的主要因素 ,提出军人心理应激管理应注意从个体水平和组织水平两方面进行

超重核~(294)118和~(291)116及其α衰变链上各核素半衰期的研究

运用推广的液滴模型(GLDM)确定了超重核294118和291116及其α衰变链上各核素的衰变势垒,采用量子力学中的WKB方法计算α衰变中的势垒穿透几率,对该链上各原子核的α衰变半衰期进行了研究。此外,还利用Royer公式对该链上各原子核的α衰变半衰期进行了计算。结果表明,GLDM考虑亲和能与Royer公式给出的α衰变半衰期与超重核区的实验值符合很好,验证了GLDM和Royer公式在超重核区的适用性,可以用来预测超重核的半衰期。最后,预言了Z=118和116同位素链上各核素的半衰期,结果表明,在Z=118和116中存在α衰变长寿命同位素,这需要实验上的检验