分光光度法测定食品中的锗

在浓度为 1 .2 mol/ L的 HCl介质中 ,苯芴酮与锗反应生成橙红色络合物 ,λmax=5 30 nm,ε=3× 1 0 4 L· mol- 1 · cm- 1 ,锗含量在 0 .5 - 5 0μg/ 5 0 m L范围内符合比尔定律 ,本方法用于食品中锗的测定 ,结果令人满意。     

氯磺酚偶氮硫代若丹宁光度法测定铂

本文研究了氯磺酚偶氮硫代若丹宁 (HSCT)与铂的显色反应 ,在盐酸介质中 ,HSCT与铂反应生成 2∶ 1稳定络合物 ,λmax=5 3 5 nm,ε=6.2 4× 1 0 4 L· mol-1· cm-1。铂含量在 0— 5 0 μg/2 5 m L范围内符合比耳定律 ,方法用于催化剂中铂含量的测定     

对乙酰基偶氮氯膦与镧显色反应的研究及应用

研究了对乙酰基偶氮氯膦与镧的显色反应 ,在 0 .2 mol/L 盐酸介质中 ,有乙醇及吐温 - 80存在时 ,生成3∶ 1紫色络合物。 λmax=6 75 nm,ε=7.33× 1 0 4 L· mol- 1· cm- 1。采用双波长法 ,以 5 30 nm为参比波长 ,6 75 nm为测定波长 ,ε=9.2 0× 1 0 4 L· mol- 1· cm- 1 ,镧含量在 0— 37.5 μg/2 5 m L范围内符合比耳定律。本法用于电子工业钛酸镧烧结中游离氧化镧的测定 ,结果令人满意。     

2-(2''-喹啉偶氮)-5-二甲氨基苯甲酸光度法测定钢铁中的钴

合成了新试剂 2 - (2’-喹啉偶氮 ) - 5 - N,N-二甲氨基苯甲酸 (QADMAB) ,并研究了其与钴的显色反应 ,在 p H=4 .0的 KH2 PO4- K2 HPO4缓冲介质中 ,CTMAB存在下 ,QADMAB与钴反应生成 2∶ 1稳定配合物 ,λmax=6 2 0 nm,ε=1.2 5× 10 5L·mol-1· cm-1。钴含量在 0— 0 .4 mg/ L范围内符合比耳定律 ,方法用于钢铁样品中钴含量的测定 ,结果令人满意     

微波消化-分光光度法测定烟草中的镁

研究了偶氮氯膦 - 与镁的显色反应 ,在 p H=10 .0硼砂 -氢氧化钠缓冲介质中 ,偶氮氯膦 - 与镁反应生成 1∶ 1稳定的络合物 ,λmax=6 10 nm,ε=2 .34× 10 4L· mol-1· cm-1。镁含量在 0— 15μg/ 2 5 m L范围内符合比耳定律 ,结合微波消化样品技术 ,建立了一种烟草样品中镁含量的测定方法 ,结果令人满意     

新亚铜灵试剂光度法测定烟草中的铜

研究了在 Emulsifier- OP存在下新亚铜灵试剂 (NHCM)与铜的显色反应 ,在 p H为 4.5的 HAc- Na Ac缓冲介质中 ,Emulsifier- OP存在下 ,NHCM与铜反应生成 2∶ 1稳定络合物 ,λmax=46 0 nm,ε=1 .6 4× 1 0 4 L·mol- 1 ·cm- 1 。铜含量在 0— 5 0 μg/2 5 m L 范围内符合比耳定律 ,该方法用于烟草中铜含量的测定 ,结果令人满意。     

分光光度法测定环境水样中的汞

研究了氯磺酚偶氮硫代若丹宁 ( HSCT)与汞的显色反应 ,在醋酸介质中 ,HSCT与汞反应生成 2∶ 1稳定络合物 ,λmax=5 4 5 nm,ε=5 .66× 10 4 L· mol-1· cm-1。汞含量在 0— 2 .5μg/ m L范围内符合比耳定律 ,本方法可用于水样中痕量汞含量的测定     

对硝基酚荷移分光光度法测定甲氧苄啶的含量

在水溶液中甲氧苄啶与对硝基酚发生反应生成 1∶ 1的荷移络合物。络合物最大吸收波长 4 0 2 .4 nm,线性范围 2— 2 5 μg/ m L,表观摩尔吸光系数为 ε=8.4 6 8× 10 3 L· mol-1· cm-1,回收率为99.6 7%— 10 0 .4 % ,相对标准偏差为 1.3% (n=5 )。本法测定甲氧苄啶药物制剂含量 ,结果令人满意。     

微波消化-分光光度法测定铂

在盐酸介质中对氨基苯基亚甲基若丹宁 (ABR)与铂的显色反应 ,生成 2∶ 1稳定络合物 ,λmax=5 2 5 nm,ε=5 .98× 10 4L·mol-1·cm-1。铂含量在 0— 5 0 μg/ 2 5 m L范围内符合比耳定律 ,方法可用于催化剂中铂含量的测定。     

亚叶酸钙与对硝基酚荷移反应的研究

本文主要研究了在水溶液中亚叶酸钙与对硝基酚发生荷移反应生成稳定的 1∶ 1络合物 ,络合物的最大吸收波长为 4 0 2 .2 nm,表观摩尔吸光系数为 ε=5 .2 5 5× 10 2 L· mol-1· cm-1,线性范围为 5 0—12 0 0 μg/ m L。回收率为 99.5 8%— 10 2 .6 0 % ,相对标准偏差为 1.4 3%。方法简单、快速、准确度高 ,可用于亚叶酸钙制剂含量的测定。     

Self-organization of five species in a cyclic competition game

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.     

Contrastive analysis on tone between Putonghua and Taiwan Mandarin

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.     

Experimental study on downstep in Chinese intonation

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.     

Abelian-Higgs phase of SU(2) QCD and glueball energy

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].     

Signal generation in an isotropic medium in scanning electron acoustic microscope

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.     

High efficiency filtering using two-dimensional photonic crystal coupled cavity structures

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.     

Real-time restoration of rotational blurred image using gradient-loading

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.     

All-Optical Logic Device Using Bent Nonlinear Tapered Y-Junction Waveguide Structure

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.     

Real-time, continuous-wave terahertz imaging by a pyroelectric camera

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.