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1.
采用高效液相色谱法测定盐酸二氧异丙嗪的含量。色谱柱为 DIKMATMRPC18(4 .6 mm× 2 0 cm,5 μm) ,流动相为乙腈 - 0 .5 %磷酸二氢钾 -三乙胺 (5 0∶ 5 0∶ 0 .2 ) ,用磷酸调 p H值至 6 .8± 0 .1;流速为1.0 m L/ min,检测波长为 2 6 4nm。该法回收率为 99.6 % ,RSD=0 .6 1%。盐酸二氧异丙嗪在浓度为0 .0 184 8— 0 .0 4 312 mg/ m L范围内线性关系良好。相关系数为 r=0 .9999。该方法操作简便 ,结果准确可靠。  相似文献   

2.
高效液相色谱法测定富马酸异哌丙吡仑   总被引:2,自引:0,他引:2  
采用高效液相色谱法测定富马酸异哌丙吡仑的含量。色谱柱为 DIKMATMRPC18(4 .6 mm× 2 0 cm,5 μm) ,流动相为乙腈 - 0 .5 %十二烷基硫酸钠 -三乙胺 (5 5∶ 4 5∶ 0 .2 ) ,用冰醋酸调 p H值至 7.0± 0 .1;流速为 1.0 m L/ min,检测波长为 2 6 5 nm。该方法回收率为 99.8% ,RSD=0 .4 4%。富马酸异哌丙吡仑在浓度为0 .0 5 92 8— 0 .1383mg/ m L范围内线性关系良好。相关系数为 r=0 .9997。该方法操作简便 ,结果准确可靠。  相似文献   

3.
火焰原子吸收光谱法测定栽培甘草中6种金属元素   总被引:4,自引:0,他引:4  
浓硝酸 -高氯酸 (V∶V=4∶ 1 )常压微沸条件下消解甘草样品 ,火焰原子吸收法 (FAAS)测定甘草中的金属元素 Ca、Mg、Fe、Cu、Zn、Pb的含量 ,研究了测定不同元素的仪器最佳工作条件及溶液介质对测定结果的影响及方法的准确性和精密度研究。栽培甘草中 Ca、Mg、Fe、Cu、Zn的含量分别为 4 0 4 5 .5、71 5 .4、2 79.8、1 2 .6、1 0 .4 μg/g,Pb未检出。方法的加标回收率为 99.38%— 1 0 2 .30 %,相对标准偏差 (n=9)为0 .4 1 %— 1 .6 8%。本法简单易行 ,方便快捷 ,结果可靠。  相似文献   

4.
偶氮胂(Ⅲ)光度法测定催化剂中的镧   总被引:5,自引:0,他引:5  
王敏 《光谱实验室》2004,21(2):390-392
研究了分光光度法测定催化剂中的镧含量。在 p H=2 .8— 3.0条件下 ,镧与偶氮胂 ( )显色生成稳定络合物 ,最大吸收波长为 6 5 8nm,表观摩尔吸光系数 ε658=5 .2 3× 10 4L· mol-1· cm-1,线性范围为 0—5 0μg/2 5 m L ,相对标准偏差 <2 % ,加标回收率为 98%— 10 2 % ,方法准确、可靠。  相似文献   

5.
微波消解-ICP-AES法测定铁矿中P和S   总被引:1,自引:0,他引:1  
采用微波加热 ,在高温高压下酸消解样品 ,应用电感耦合等离子体原子发射光谱法 (ICP- AES)同时测定铁矿中杂质元素 P和 S。选用紫外区谱线 P178.2 2 1nm、S180 .6 6 9nm,避免了基体中大量存在的 Fe、Si、Al、Cu、Mn、Ca等元素的光谱干扰。通过用纯氮吹扫光谱仪光路的方法消减空气中氧对紫外线的吸收 ,获得了足够的灵敏度。该方法简便、快速、稳定可靠 ,P、S检出限分别为 0 .0 6 7、0 .0 78μg· m L-1,回收率为89.6 %— 10 0 .7% ,RSD为 1.35 %— 5 .0 5 % ,线性范围为 0 .1— 2 0 0 μg·m L-1。  相似文献   

6.
薄层层析-分光光度法测定南瓜中β-胡萝卜素   总被引:2,自引:0,他引:2  
石油醚∶丙酮 (7∶ 3)混合液作提取剂 ,薄层层析 -分光光度法测定了南瓜中 β-胡萝卜素的含量 ,对该法的精密度、准确性进行了探讨。在 β-胡萝卜素的最大吸收波长 4 5 0 nm下 ,回归方程为 A=0 .0 2 4 0 5 6 C-0 .0 0 2 4 6 4,r=0 .998。测定结果的相对标准偏差在 2 .0 1%— 4 .5 2 %之间 ,回收率在 94 .5 0 %— 97.2 0 %之间 ,检出限为 0 .5 μg  相似文献   

7.
李省云 《光谱实验室》2004,21(5):962-965
盐酸精氨酸与四氯苯醌在硼砂溶液中 ,5 0℃下反应 1 2 0 min可获得 1∶ 1稳定的电荷转移络合物 ,其λmax=35 0 nm,表观摩尔吸光系数 ε=2 .2 6× 1 0 4L·mol-1 · cm-1 ,线性范围为 0— 1 0 μg/m L。测定了盐酸精氨酸注射液的含量 ,结果与文献方法一致 ,回收率在 1 0 0 .0 %— 1 0 0 .3%之间 ,相对标准偏差小于 0 .70 %。  相似文献   

8.
在表面活性剂CPB和乳化剂OP存在下 ,利用二溴羟基苯基荧光酮 (DBH PF)与铜 (Ⅱ )显色反应 ,建立了测定微量Cu(Ⅱ )的光度法。实验结果表明 ,在pH =5 4的六次甲基四胺 盐酸缓冲溶液中 ,DBH PF与Cu(Ⅱ )生成紫红色的络合物 ,最大吸收波长为 5 40nm ,表观摩尔吸光系数为 1 8× 10 5,Cu(Ⅱ )的质量浓度在 0 0~ 9 0 μg·2 5mL-1范围内符合比耳定律。结合N53 0 N510 混合萃取分离可准确测定电镀废水中微量铜。  相似文献   

9.
提出了一种简易冷原子吸收测定废水样品中的痕量汞的新方法。探讨了实验参数及共存离子对分析结果的影响。检出限为 0 .39μg/ L(3σ) ,回收率在 94 %— 1 0 4 %之间 ,相对标准偏差 (2 0 μg/ L,n=6 )为 3.2 %。方法简便快速 ,线性范围宽 ,具有较高的灵敏度和准确度 ,可以满足实际样品测定的要求  相似文献   

10.
于庆水  粟智 《光谱实验室》2004,21(5):974-976
在盐酸介质中 ,以 Na Cl为催化剂 ,Br O-3 氧化亚甲蓝褪色 ,建立了分光光度法测定痕量溴酸根的新方法。研究了溴酸根氧化亚甲蓝褪色的最佳条件 ,最大吸收波长 λmax=6 6 8nm,表观摩尔吸光系数为 4 .2 4×1 0 4L· mol-1 · cm-1 ,Br O-3 的浓度在 5× 1 0 -8— 4× 1 0 -6mol· L-1 范围内符合比耳定律 ,回归方程为 :ΔA=9.372× 1 0 4C 0 .0 5 5 82 ,相关系数 r=0 .9993。方法用于化学试剂中溴酸根测定得到了较好的分析结果。  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.
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   

13.
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   

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.
16.
Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.  相似文献   

17.
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   

18.
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   

19.
The key to the restoration of rotational motion blurred image is how to restore the image under a low cost and to correct the irreversibility of the degradation function matrix.Based on the special qualities of degradation function matrix and precise deduction in space-domain, we present a new approach using gradient-loading for restoration of rotational blurred image.By easily adding a gradient operator, the irreversibility of the original matrix is corrected and can be applied for inverse filtering then.Gradientloading is the optimized approach which combines the advantages of both the approaches using constrained least square filtering and traditional diagonal-loading.Compared with the approach using least square filtering, its peak signal-to-noise ratio (PSNR) is improved from 3.18 to 6.46dB, while the computing time is reduced to 1/2-1/3.Experimental results demonstrate the effectiveness, noise-resistibility, robustness, and low complexity of this approach, which make it more suitable for real-time environment.  相似文献   

20.
We propose an all-optical logic device made of a bent tapered Y-junction waveguide with a Kerr-type nonlinear interface. It could provide an AND gate, OR gate, and exclusive-OR (XOR) gate. We could obtain different transmission results by adjusting the bending angle. The numerical simulation results show that the device functions as AND, OR, and XOR gates.  相似文献   

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