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1.
N2O/C2H2FAAS法测定铝的干扰研究   总被引:1,自引:1,他引:0  
本文研究了40种单个无机离子、混和无机离子及24种有机物在N2O/C2H2火焰中对铝吸收信号的干扰情况。并从物理干扰、光谱干扰和化学干扰等角度对它们的干扰机理作了解释。  相似文献   

2.
近红外光谱技术用于复杂植物样品中无机离子测定的新方法   总被引:20,自引:1,他引:19  
植物样品中的无机离子以一定形式与具有近红外吸收的有机基团结合,因而可以借助近红外光谱技术测定其含量。对烟草样品近红外光谱数据及其小波变换处理后的小波系数,采用偏最小二乘法预测其中钾离子的含量,建立了小波变换与近红外光谱技术结合用于复杂植物样品中无机离子测定的新方法。结果表明:近红外光谱数据压缩为原始大小的3.3%,基本上没有光谱信息的丢失;基于小波系数的模型优于传统的全谱模型,对于无机离子的测定可以取得较为准确的预测结果。  相似文献   

3.
固态电解质被认为是解决传统液态锂金属电池安全隐患和循环性能的关键材料,但仍然存在离子电导率低,界面兼容性差等问题.设计兼顾力学性能、离子电导率和电化学窗口的有机-无机复合型固态电解质材料是发展全固态锂电池的明智选择.近年来,基于无机填料与聚合物电解质的有机-无机复合电解质备受关注.设计与优化复合电解质结构对提高复合电解质综合性能具有重要意义.本文详细梳理了有机-无机复合固态电解质在全固态锂电池中展现的多方面优势,从满足不同性能需求的复合电解质结构设计角度出发,综述了有机-无机复合电解质在锂离子传导、锂枝晶的抑制、界面稳定性和相容性等方面的研究进展,并对有机-无机复合电解质的未来发展趋势和方向进行了展望.  相似文献   

4.
胶体锰离子掺杂的纯无机钙钛矿纳米晶由于其优异的光电性质,使其作为一种新兴的荧光发射材料,被研究者们广泛研究。不仅如此,纯无机钙钛矿纳米晶的锰离子掺杂行为也揭示了由于掺杂过程和掺杂剂本身引起的新的光学性质。通过不同的合成方法和选择不同的锰前驱体可以实现不同的掺杂行为,以及由此引发不同的荧光性质。在高带隙钙钛矿主体中进行锰离子掺杂时,其中激发能量由钙钛矿主体转移到掺杂锰离子位点的d态,进而产生橙黄色d-d发射荧光。研究者们一直致力于理解锰离子掺杂过程并由此设计高效掺杂的纳米晶。这些锰离子掺杂的钙钛矿纳米晶由于具有独特的电子和光学特性使其在发光二极管和太阳能电池等应用中发挥了巨大的作用。结合之前的相关工作和进展,本综述重点总结了锰离子掺杂的纯无机钙钛矿纳米晶的合成方法、发光来源、发光机理和潜在应用的最新进展,并提出了未来潜在合理的研究方向。  相似文献   

5.
利用衰减全反射-傅里叶变换红外(ATR-FTIR)光谱技术探讨了气溶胶颗粒物中SO_4~(2-),NO_3~-,NH_4~+三种水溶性无机离子的快速无损测量方法。利用IC法测量三种无机离子含量的对照值,结合偏最小二乘(PLS)法建立了三种无机离子的定量分析模型,并对模型进行了评价;利用马氏距离判别法对异常值进行了判别与剔除,并探讨了不同光谱预处理方法和不同光谱范围对建模结果的影响,确定了最佳建模参数。结果表明剔除异常值之后经二阶微分处理的模型预测性能较好,SO_4~(2-)在1 220~900cm~(-1)光谱范围内预测性能较好,NO_3~-在1 521~900cm~(-1)光谱范围内预测性能较好,NH_4~+在1 521~1 220cm~(-1)光谱范围内预测性能较好,预测均方根误差分别为1.736 7,1.023 9和1.482 3。所建立的模型为实现对大批量气溶胶样品中三种无机离子的实时快速定量分析建立了基础。  相似文献   

6.
离子色谱法进展   总被引:2,自引:0,他引:2  
本文综述了近 30年来离子色谱在无机阴、阳离子 ,有机酸、碱和复杂样品分析方面的进展  相似文献   

7.
采用红外反射光谱与和频光谱,研究了三辛基氧膦(TOPO)分子与水溶液中各种无机离子的界面相互作用。从分子水平解释了水溶液中各种共存离子对有机膦萃取剂萃取目标金属离子行为的影响,有助于萃取过程机理的理解和工艺参数的优化。  相似文献   

8.
研究了在不同基质玻璃中Ce3+、Tb3+、Er3+和Tm3+离子的吸收、荧光和激发光谱,对发光强度进行了定量的测定。研究了玻璃基质的紫外吸收对发光的影响,并且讨论了无机玻璃的配位场与上述稀土离子的相互作用。  相似文献   

9.
《物理》1991,(11)
中国硅酸盐学会固态离子学专业委员会订于1992年11月3-6日在福州大学召开第六届全国固态离子学学术讨论会.福州大学校长黄金陵教授为本届会议筹备委员会主任. 征文内容:1. 无机阳离子导体.2.无机阴离子导体.3混合导体.4.质子导体.5.高分子快离子导体.6.固体中离子的运动与离子缺陷.固态离子学中的基础研究.7.固态离子学中的测试技术.8.高Tc超导体.9.快离子导体的应用研究:(1)固体电解质电池;(2)电化学传感器;(3)电显色器件.11.其他. 注意事项:1.应征论文必须是未在国内、外刊物上公开发表过;2.请将论文摘要(16开一页,约700字) 一式三份于19…  相似文献   

10.
运用发射FTIR光谱技术,实时监测SBA-15掺杂制备的复合聚合物电解质随温度升高其结晶状态变化的规律,结合电化学和SEM研究结果分析了无机填料对离子电导率的影响,并初步提出离子导电增强的机制.文章将为发射FTIR光谱技术应用于锂电池研究进行了探索.  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.
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   

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.
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   

19.
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   

20.
Real-time, continuous-wave terahertz imaging by a pyroelectric camera   总被引:1,自引:0,他引:1  
Real-time, continuous-wave terahertz (THz) imaging is demonstrated. A 1.89-THz optically-pumped farinfrared laser is used as the illumination source, and a 124 × 124 element room-temperature pyroelectric camera is adopted as the detector. With this setup, THz images through various wrapping materials are shown. The results show that this imaging system has the potential applications in real-time mail and security inspection.  相似文献   

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