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1.
乙醛在黄嘌呤氧化酶催化作用下,被空气氧化生成乙酸和过氧化氢,酶反应生成的过氧化氢氧化新吖啶酯试剂[10-甲基-9-(对甲酰苯基)吖啶羧酸酯氟磺酸盐]产生化学发光,化学发光强度与己醛浓度在一定范围内成线性关系.由此建立了一种化学发光分析新体系,用于测定乙醇含量.线性范围2.0×10-7~1.2×10-3mol/L,测定5.0×10-7mol/L乙醛,相对标准偏差为6.8%,检测限为1.2×10-7mol/L,测定环境水样中乙醇含量,取得满意结果,回收率为95~106%.  相似文献   

2.
Fe(Ⅲ)-灿烂绿-过氧化氢测定痕量铁   总被引:5,自引:0,他引:5  
本文研究了在PH=3.0的酸性条件下,利用铁催化过氧化氢氧化灿烂绿的反应,建立了催化动力学光度法测定痕量铁的新方法。方法检出限为4*10^-9g/mL,线性范围内0.1-1.0μg/25mL,ε=2.50*10^4cm^-1,L.mol^-1,用于水样中痕量铁的测定,结果满意。  相似文献   

3.
用紫外吸光光度法对硫酸介质安宫黄体酮与溴代十六烷基吡啶形成的胶束配合物的性能和条件进行了系统研究,提出了利用胶束的增敏、增稳作用测定安宫黄体酮的紫外吸光光度新方法。本法灵敏度高,表观摩尔吸光系数ε280为5.610*10^4L.mol^-1.cm^-1,检出限为2.9*10^-8mol.L^-1。该方法用于片剂中安宫黄体酮含量的测定,与药典法对照结果吻合。  相似文献   

4.
马红燕 《光谱实验室》1999,16(5):548-550
提出了在PH10.38的碱性介质中高灵敏度测定氢化可的松的荧光光度新方法。方法灵敏度高,检出限为2.8×10^-9mol·L^-1;线性范围为5.518×10^-9-3.862×10^-6mol·L^-1。应用本法测定注射液中氢化可的松,平均回收率为99.3%,结果令人满意。  相似文献   

5.
本文用荧光光度法对硫酸介质中螺内酯和十二烷基硫酸钠(SDS)形成的胶束配合物的进行了系统研究。利用胶束的增敏增稳作用,提出了测定螺内酯的荧光光度新方法,方法线性范围宽,为1.4×10^-9-4.3×10^-6mol·L^-1,灵敏度高,检出限为1.2×10^-9mol·L^-1,应用本法于片剂中螺内酯的测定,结果满意。  相似文献   

6.
催化动力学光度法测定痕量铁(Ⅲ)的研究   总被引:2,自引:0,他引:2  
在弱酸性介质中,利用铁(Ⅲ)对高磺酸钾氧化溴酚蓝的催化作用,建立了催化光度测定痕量铁(Ⅲ)的新方法。该方法线性范围在0-1.2μg/25mL之间,检出限为3.1*10^-10g.mL^-1。测定出反应表观活化能为Ea=98.66kJ/mol。此法用于水样中微量铁的测定,结果令人满意。  相似文献   

7.
本主要研究了3-溴-N-乙基吩噻嗪(Br-P)在各种酸度、增敏溶剂、感光效应等条件下的荧光变换现象,并确定了最佳的发光体系。方法简单、准确可靠,其线性范围为1×10^-7 ̄1×10^-4mol/L,检出限为1×10^-8mol/L,RSD〈2.8%。  相似文献   

8.
在磷酸介质和90℃水浴中加热的条件下,痕量铑(Ⅲ)能灵敏地催化高碘酸钾氧化二安替比林对二乙氨基苯基甲烷(DAEAM)的显色反应。研究了该催化反应的最佳实验条件及动力学参数,建立了一种动力我度法测定痕量铑的新方法。方法的线性范围为20-140μg/L;检出限为2.0*10^-8g/mL,催化反应的表观活性能为94.30kJ/mol,表观速率为1.56*10^-4/。本法已用于某些贵金属溶液中的铑的测定,其相对标准偏差为3.1%-3.4%,加标回收率为98.3%-99.4%。  相似文献   

9.
本文对应用Fura-2AM荧光法测定细胞肌浆中的自由钙离子浓度时几种影响其测量精度的因素进行了讨论,提出了用化学去膜方法加以改进。在此基础上,测量了处于静息状态时完整蟾蜍骨骼肌细胞肌浆内自由钙离子浓度,其值为(116.8±5.3)×10^-9mol/L,而常用的方法得出相应用结果为(122.2±4.1)×10^-9mol/L。  相似文献   

10.
张林 《光谱实验室》1996,13(1):14-17
在0.15mol/LHAc-NH4Ac支持电解质中,使用0.1g/L的邻菲罗啉(o-Phen)采用经典极谱仪测定其离子络合物吸附波,分光光度法测定铁离子,检出下限分别达到:铅离子为1.50×10^-10mol/L,铁离子为3.581×10^-7mol/L。该方法在回收率为99.2%-100.4%之间,具有较好的选择性。  相似文献   

11.
Cyclic competition game models, particularly the “rock–paper–scissors” model, play important roles in exploring the problem of multi-species coexistence in spatially ecological systems. We propose an extended “rock–paper–scissors” game to model cyclic interactions among five species, and find that two of the five can coexistent when biodiversity disappears, which is different from the “rock–paper–scissors” game. As the number of fingers is five, we named the new model the “fingers” game, where the thumb, forefinger, middle finger, ring finger, and little finger cyclically dominate their subsequent species and are dominated by their former species. We investigate the “fingers” model in two ways: direct simulations and nonlinear partial differential equations. An important finding is that the number of species in a cyclic competition game has an influence on the emergence of biodiversity. To be specific, the “rock–paper–scissors” model is in favor of maintaining biodiversity in comparison with the “fingers” model when the variables (population size, reproduction rate, selection rate, and migration rate) are the same. It is also shown that the mobility and reproduction rate can promote or jeopardize biodiversity.  相似文献   

12.
The differences of the pitch and duration of Chinese syllables between Putonghua (PTH) and Taiwan Mandarin (TM) were studied. The speech materials to be used are not only isolated syllables, but also sentences. The results reveal that: For the isolated syllables, T1 and T2 in TM are influenced by Minnan dialect, therefore their pitch are lower than those in PTH. T3 is fall-rise in PTH, while it is fall in TM. Moreover, the syllable duration sequence for different tone is T3〉T2〉T1〉T4 in PTH, while it is T1〉T2〉T3〉T4 in TM. For the syllables in sentences, T2 is mid-rise in PTH, while it is mid-level in TM. And the T3 is longer than T4 but shorter than T1 or T2 in PTH, while it is the shortest in TM. Furthermore the effects of prosodic phrase boundary on duration for different tones are almost the same in PTH, but the lengthening part of T1 or T2 is longer than that of T3 or T4 in TM.  相似文献   

13.
Downstep in pitch contour of Chinese Putonghua is examined using subtly designed sentences by controlling tone combinations. The results show both automatic and nonautomatic downstep phenomena exist in Chinese. In non-automatic downstep, low tones compress downwards the pitch range of the following syllables. and the main influence of downstep is on topline. Low tone not only lower the topline behind it, but also raise the high tones before it, the effects are compatible with each other. In automatic downstep, the topline of pitch contour in intonational phrase is presented as a linear downtrend, but it differs among speakers due to the effect of personal stress practice. In comparison with downstep phenomenon in other tone or non-tone languages, the downstep ratio in Chinese is not constant, and the domain of downstep is not limited within the adjacent tones.  相似文献   

14.
It is shown that SU(2) QCD admits an dual Abelian-Higgs phase, with a Higgs vacuum of a type-Ⅱ superconductor. This is done by using a connection decomposition for the gluon field and the random-direction approximation. Using a bag picture with soft wall, we presented a calculational procedure for the glueball energy based on the recent proof for wall-vortices [Nucl. Phys. B 741(2006)1].  相似文献   

15.
A multi-conjugate adaptive optics (MCAO) can offer a possibility of widening field of view (FOV) characterized by the isoplanatic angle, and the choose of conjugate height becomes a basic problem for MCAO, which influences the size of iosplanatic angle. Considering the application of lidar, the isoplanatic angle's expressions of two deformable mirrors (DMs) MCAO for uplink and downlink are deduced. The effects of conjugate heights for dual-conjugate AO are thoughtfully discussed, and the isoplanatic angles are further analyzed. The results show that the isopanatic angle varies with the conjugate height and reaches the maximum as the conjugate height is at the optimal altitude. Moreover, the optimal conjugate height changes with the propagation distance.  相似文献   

16.
Due to the limit of response speed of the present single-photon detector, the code rate is still too low to come into practical use for the present quantum key distribution (QKD) system.A new idea is put up to design a quick single-photon detector.This quick single-photon detector is composed of a multi-port optic-fiber splitter and many avalanche photo diodes (APDs).Au of the ports with APDs work on the time division and cooperate with a logic discriminating and deciding unit driven by the clock signal.The operation frequency lies on the number N of ports, and can reach N times of the conventional single-photon detector.The single-photon prompt detection can come true for high repetition-rate pulses.The applying of this detector will largely raise the code rate of the QKD, and boost the commercial use.  相似文献   

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19.
Based on the research in Ref. [5][Materials Science and Engineering, 1989; A122: 57 63], an improved model of heat source is set up, the different modes of Lamb wave in an isotropic sample generated by a chopped electron beam at frequency f are obtained with integral transform and normal function expansion method, and the output signal of PZT coupled at the back surface of the sample is found out. The generation mechanism of SEAM (Scanning Electron Acoustic Microscopy) signal is discussed. It shows that the SEAM is a near field imaging technique with high spatial resolution and its best lateral spatial resolution is about 2√2α (α is the radius of the focused electron beam). Some of experimental results of SEAM images are presented in the paper and it shows that the spatial resolution of SEAM is better than 0.5 μm and smaller than the thermal diffusion length of the sample. Therefore the character of near field imaging in SEAM is also proved experimentally.  相似文献   

20.
Transmission spectra of coupled cavity structures (CCSs) in two-dimensional (2D) photonic crystals (PCs) are investigated using a coupled mode theory, and an optical filter based on CCS is proposed. The performance of the filter is investigated using finite-difference time-domain (FDTD) method, and the results show that within a very short coupling distance of about 3λ, where λ is the wavelength of signal in vacuum, the incident signals with different frequencies are separated into different channels with a contrast ratio of 20 dB. The advantages of this kind of filter are small size and easily tunable operation frequencies.  相似文献   

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