共查询到20条相似文献，搜索用时 31 毫秒
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本文介绍一种自制的低真空与气体光谱实验仪,作为简单的低真空实验,可测气压、抽速、气压与放电点火电压的关系,作为光谱实验,可测谱线波长、光栅常数。 相似文献
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张晓娟 《渭南师范学院学报》2011,26(2):14-20
采用分步傅里叶算法模拟分析了超短脉冲在三类具有不同色散曲线的光子晶体光纤中传输时的非线性传输及超连续谱产生,讨论了入射脉冲条件不同对产生超连续的影响．结果表明：相比较而言,在反常色散区形成的频谱最宽,依次是近零反常色散光子晶体光纤,同样条件下,输入脉冲位于正常色散区时频谱展宽最小． 相似文献
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中性红水溶液电离平衡体系的紫外可见吸收光谱特征是酸式HNR+最大吸收峰542 nm与碱式NR最大吸收峰 457～ 470 nm叠合在一起.当pH值升高时,碱式吸收峰强度逐渐增大,酸式吸收峰强度逐渐减小.首次将高斯多峰拟合技术用于中性红水溶液电离平衡体系紫外可见吸收光谱分析,实现了酸式和碱式叠合峰的分峰拟合计算,得到两个吸收峰的积分面积,即峰强度S1和S2.S1和S,之比与NR-和HNR+浓度之比成正比,进而计算中性红水溶液酸离解常数pKa.26.4℃时,用本方法测量的pKa值为7.20,拟合优度精度高,R2、Chi2分别达到0.999和10-5 ～10-6.拟合计算结果还表明:随着体系pH值增加,中性红碱式吸收峰发生显著蓝移.这种波长位移引起由固定波长建立起来的浓度与吸光度的线性关系发生偏离,引起约3％系统误差高斯多峰拟合技术改进的pKa分光光度测量方法可广泛用于此类多组分体系紫外可见吸收光谱研究. 相似文献
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This paper presents a novel method of identifying coal type based on mechanistic methods. The ratio of the resonance line spectrum of a luminous flame and the continuous spectrum at the same wavelength eliminates the influence of temperature on spectral intensity. The atomic line spectra of Na and K are typical and significant over continuous flame spectra. The concentrations of elemental Na and K in the flame are exclusively relative to coal type and composition. Using an experimental furnace and charge-coupled device (CCD) optical spectrometer apparatus, the continuous spectra and atomic line spectra of Na and K elements were sampled from coal flames in real time. An empirical fitting method was used to simplify the formulas of absorption strength and flame temperature calculation, and rational solutions were obtained by using an iterative algorithm. Due to the change in reaction rate and absorption by soot particles, the relative contents of Na and K in a flame vary with the temperature and absorption strength. Arrhenius’s equation for temperature compensation was adopted. Compensation for soot density in the furnace was also satisfied by an exponential expression. At any one sampling position, the compensation parameters were identical for all coal types. After compensation for temperature and density of soot particles, the relative strength of the Na and K signals and the ratio between them uniquely matched the coal type burnt in various conditions. The results were replicated and verified in various conditions, and the response time of the system was of the order of seconds. 相似文献
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在可见光区内,以汞灯、钠灯、氢灯和氦氖激光器所产生的已知各主要光谱线波长,利用最小偏向角法对重火石玻璃ZF1棱镜的色散关系进行测量,并采用多种方法进行非线性拟合,得到相应的色散曲线和色散公式.通过重火石玻璃ZF1棱镜折射率在不同波长下的计算结果与测量值进行比较,确定计算折射率的最佳色散公式.同时对色散曲线特点及色散公式进行了讨论. 相似文献
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A discrimination measurement method and demodulation technique for fiber Bragg grating （FBG） sensors were presented using digital filtering technique. The system can control a tunable fiber Fabry-Perot filter with sawtooth wave voltage generated by digital clock to interrogate FBG sensors. Using the analogue digital converter （ADC）, the reflected FBG signals were sampled with synchronous digital clock. With the aid of digital matched filtering technique, the sampled FBG signals were processed to obtain the maximum signal-to-noise ratio （SNR） and the Bragg wavelength shift from the FBG signals was recovered. The results demonstrate that this system has a scanning range of 1 520 nm-1 575 nm,and the wavelength detection accuracy is less than 2 pm with 1.5 Hz scanning frequency. 相似文献
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The ultrasonic motor （USM） possesses heavy nonlinearities which vary with driving conditions and load-dependent characteristics such as the dead-zone. In this paper, an identification method for the rotary travelling-wave type ultrasonic motor （RTWUSM） with dead-zone is proposed based on a modified Hammerstein model structure. The driving voltage contributing effect on the nonlinearities of the RTWUSM was transformed to the change of dynamic parameters against the driving voltage. The dead-zone of the RTWUSM is identified based upon the above transformation. Experiment results showed good agreement between the output of the proposed model and actual measured output. 相似文献
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测量了1．62at％-Er^3＋ Y0.5Gd0．5，VO4晶体的吸收光谱和荧光发射谱，光谱显示该晶体在382、525、1536nm有很强的偏振光吸收峰，且偏振光（E∥C）吸收远强于σ偏振光（E⊥C）吸收；通过计算可得，吸收截面分别为2．95013×10^-20cm^2、2．57757×10^20cm^2和1．15504×10^-20cm^2；其荧光发射（^4I15／2→^4I11／2跃迁）峰值波长在1524nm，半高宽度为72nm；415/2^I→^4I11/2跃迁的荧光寿命为3．1ms,光谱特性表明Er3^＋：Y0．5，Gd0．5，VO4晶体是潜在的高效率激光晶体材料． 相似文献
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M. Farooq Wahab 《Resonance》2009,14(10):996-1002
A functional monochromator model in a cardboard box, made from rotatable grating using a digital versatile disk is described
to highlight the working principles of a UV-Vis monochromator. The light source is a bright white LED and the colored bands
from the exit are displayed on the screen. The concept of absorption, complementary color, excitation and fluorescence, flame
emission spectrum, and wavelength dependence of light scattering can be visually shown in this model. With a minor modification,
one can use the same box to monitor flame emission spectrum of sodium and different light sources. As an optional activity,
the same properties are observed on a scanning spectrophotometer. 相似文献
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在pH=3.78的BR缓冲溶液中,1,10-邻菲啰啉(phen)与锌(Ⅱ)形成螯合阳离子后,再进一步与曙红Y(EY)通过静电引力和疏水作用力形成离子缔合物,引起吸收光谱的变化,最大褪色波长位于516 nm,另在548 nm处产生新的吸收峰.考察了最佳的反应条件、光谱特征及方法的灵敏度与选择性,研究发现,Zn(Ⅱ)在2.0×10-6～1.0×10-4mol.L-1的浓度范围内遵守郎伯比尔定律,方法的灵敏度高,摩尔吸收系数ε为7.003×104L.mol-1.cm-1,且具有良好的选择性,对大多数离子的允许量都较大.用于实际样品的测定,结果令人满意.据此建立了一种新的测定微量锌的方法. 相似文献
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以（NH4）6Mo7O24.4H2 O,NiSO4和（NH4）2S2O8为原料合成了（NH4）6[NiMo9O32]·8H2O杂多酸盐,并利用化学分析、差热热重、红外光谱、紫外光谱、循环伏安等方法对其进行了元素分析、结构及性质的研究。样品的红外光谱分析显示：在1000-400cm^-1处由两组突出的峰组成,显示出Waugh结构单元的特征谱带;紫外可见光谱分析显示：紫外区吸收峰位置为207nm处,可见区吸收峰位置为563.2nm;差热-热重分析显示：该化合物在1067.9-1103.5K分解,说明具有较高热稳定性;循环伏安曲线显示：该电极反应为半可逆过程,是以扩散控制的表面氧化还原过程,且伴随质子化。 相似文献
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为提高甲烷浓度的检测精度,根据红外吸收光谱检测原理,推导了气体浓度跟二次谐波与一次谐波之比的关系,并利用可调谐DFB半导体激光器设计了甲烷浓度检测传感器。通过1 kHz的正弦电流叠加到激光器的电源进行调制,使光束扫描波长为3.312μm处的吸收峰,从而在碲镉汞红外探测器上产生谐波信号。同时,利用相敏检波技术设计了微弱信号处理电路,通过前置放大、带通滤波、相敏检波、直流放大等有效抑制了信道噪声,实现了对一次和二次谐波的高精度提取。实验结果表明:设计的甲烷浓度检测传感器具有较高的测量精度和稳定度,在0%~20%的量程上,最大误差不超过0.65%,平均误差仅为0.41%,可应用于在煤矿开采和化工生产中对甲烷泄漏的监测。 相似文献
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Decomposition of dimethyl sulfide （DMS） in air was investigated experimentally by using a wire-cylinder dielectric barrier discharge （DBD） reactor at room temperature and atmospheric pressure. A new type of high pulse voltage source with a thyratron switch and a Blumlein pulse-forming network （BPFN） was adopted in our experiments. The maximum power output of the pulse voltage source and the maximum peak voltage were 1 kW and 100 kV, respectively. The important parameters affecting odor decomposition, including peak voltage, pulse frequency, gas flow rate, initial concentration, and humidity, which influenced the removal efficiency, were investigated. The results showed that DMS could be treated effectively and almost a 100% removal efficiency was achieved at the conditions with an initial concentration of 832 mg/m3 and a gas flow rate of 1000 ml/min. Humidity boosts the removal efficiency and improves the energy yield （EY） greatly. The EY of 832 mg/m3 DMS was 2.87 mg/kJ when the relative humidity was above 30%. In the case of DMS removal, the ozone and nitrogen oxides were observed in the exhaust gas. The carbon and sulfur elements of DMS were mainly converted to carbon dioxide, carbon monoxide and sulfur dioxide. Moreover, sulfur was discovered in the reactor. According to the results, the optimization design for the reactor and the matching of high pulse voltage source can be reckoned. 相似文献
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自主设计开发了基于二极管激光光源的气体分子高分辨吸收光谱测量实验方案,展示了乙炔气体分子吸收光谱的测量装置、测量方法和测量结果。实验系统的光谱分辨率为0.01 pm,光谱采集速率10 Hz,最低可探测吸收0.03%,乙炔气体传感分辨率7 ppm。实验系统构建成本低、扩展性强、易于推广,可丰富光学类实验课程内容。该实验系统已开展了两学年的教学实践,取得了很好的教学效果。 相似文献
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建立一维半导体Ge的激光烧蚀模型,对波长为248nm,脉宽为17ns,峰值功率密度为4×108w/cm2的KrF脉冲激光在1000torr(1torr=133.32pa)氦气环境下烧蚀晶体Ge及产生等离子体的过程进行了数值模拟,并对计算结果进行分析比较.结果表明在惰性气体环境下,气压在1torr和1000torr之间变化对等离子体屏蔽现象的出现几乎不产生影响;背景气压的增大抑制了粒子的扩散,使等离子体的膨胀速度减小,限制了其膨胀的空间. 相似文献