阳离子表面活性剂与酚红的显色反应及其分析应用

研究了阳离子表面活性剂（ＣＳＡＡ）溴化十六烷基三甲铵（ＣＴＡＢ）、溴化十六烷基吡啶（ＣＰＢ）在水溶液中与溴酚红（ＢＰＲ）的显色反应。发现在ＰＨ５．０～６．０范围内,ＣＳＡＡ单体与ＢＰＲ形成离子缔合物（缔合比为３：２）,可用于微是ＣＳＡＡ及ＣＳＡＡ的临界胶束浓度（ＣＭＣ）的测定。本文还研究了显色２的适宜条件、分析特征,并讨论了反应机理。     

胶束体系中荧光素与四溴荧光素间能量转移条件及模型研究

研究了阳离子表面活性剂(CSAA)在水溶液中与阴离子酸性染料四溴荧光素(TBF)的荧光反应,发现当CSAA单体与TBF形成离子缔合物时,TBF的荧光发生猝灭,而CSAA胶束与TBF作用又会产生一个新的、更强的荧光。进而研究了阳离子表面活性剂CTMAB及CPB胶束体系中酸性阴离子荧光染料荧光素与四溴荧光素间的能量转移条件。表明只有在带相反电荷的CSAA形成的胶束中,阴离子染料间的能量转移才可能发生,在2/3临界胶束浓度(CMC)时能量转移效率达到最大。并推测了胶束体系中染料间能量转移模型及染料间能量转移的一般规律。     

铀-Br-PADAP-磺基水杨酸-表面活性剂体系的研究

本文研究了铀(Ⅵ)-Br-PADAP-磺基水杨酸三元络合物分别与阳离子表面活性剂溴化十六烷基吡啶(CPB)、溴化十六烷基三甲基铵(CTAB),非离子表面活性剂聚乙二醇辛基苯基醚(OP),Triton X-100的反应条件、生成物的性质和其组成,对反应机理进行了初步讨论。     

4,5—二溴邻硝基苯基荧光酮分光光度法测定铁

本文研究了4,5-二溴邻峭基苯基荧光酮在阳离子表面活性剂溴化十六烷基三甲基铵存在下,测定微量铁的显色反应。4,5-二溴邻硝基苯基荧光酮,溴化十六烷基三甲基铵与铁形成稳定的络合体系,在614纳米处有最大吸收峰,该法灵敏可靠(δ=1.47×10~5),选择性高,大部分常见元素不干扰。吸光值在24小时内不变,应用于白云石,水样及氧化镁中微量铁的测定,获得令人满意的结果。     

N2-苯浮选缔合光度法测定碘的研究

本文依据在强酸性磷酸介质中,Br2氧化I-为I2,进而与I-生成配阴离子I-3,利用溴化十六烷基三甲胺(CTMAB)与I-3发生等离子对缔合物反应,生成缔合物CTMA+*I-3,该缔合物易溶于苯,且在苯中稳定,从而建立了溶剂浮选光度法测碘新方法.本法灵敏度高,选择性强,精密度好,实测了天然水及加碘的盐中碘,结果令人满意.     

2-(2-喹啉偶氮)-1，5-苯二酚光度法测定铜的研究

合成了新试剂 2 - ( 2 -喹啉偶氮 ) - 1,5-苯二酚 ( QADHB) ,并研究了其与铜的显色反应 ,在溴化十六烷基三甲胺 ( CTMAB)存在下 ,p H=4 .0邻苯二甲酸氢钾缓冲介质中 ,QADHB与铜反应生成 2∶ 1稳定络合物 ,λmax=540 nm,ε=2 .12× 10 4 L·mol-1·cm-1。铜含量在 0— 30 μg/ 2 5m L内符合比耳定律 ,该方法用于环境样品中铜的测定 ,结果令人满意     

Fe(Ⅲ)-苯基荧光酮-溴化十六烷基三甲胺显色反应的研究与应用

本文研究了在溴化十六烷基三甲胺存在下，苯基荧光酮与铁的显色反应。试验结果表明，显色的适宜酸度为pH等于7.3至10．5，配合物的摩尔吸光系数为1．09×105L·mol-1·cm-1，铁量在0－6μg·25mL-1范围内符合比耳定律。用于试样中铁的测定，灵敏度高，且简便可靠。     

2-(2-喹啉偶氮)-4-甲基-1,3-苯二酚光度法测定铜的研究

合成了新试剂 2 - (2 -喹啉偶氮 ) - 4-甲基 - 1,3-苯二酚 (QAMDHB) ,并研究了其与铜的显色反应 ,在 p H=2 .2的磷酸 -磷酸二氢钾缓冲介质中 ,溴化十六烷基三甲基胺 (CTMAB)存在下 ,QAMDHB与铜反应生成 2∶ 1稳定络合物 ,λmax=5 5 0 nm,ε=4 .84× 10 4L· mol-1· cm-1。铜含量在 0— 2 0μg/ 2 5 m L范围内符合比耳定律 ,方法用于环境水样中铜含量的测定 ,结果令人满意     

甲基橙-溴化十六烷基吡啶分光光度法测定阴离子表面活性剂

在一定浓度的乙醇水溶液中,甲基橙(MO)可与溴代十六烷基吡啶(CPB)发生褪色反应,加入阴离子表面活性剂十二烷基硫酸钠(SDS),可使MO-CPB褪色体系增色,确定了显色体系的最大吸收波长为460nm.研究发现在最大吸收波长处,加入的SDS浓度与MO-CPB体系增色程度在一定范围内呈现良好的线性关系,当SDS的浓度在0...     

铌-酒石酸-铬天青S-溴化十六烷基吡啶分光光度法测定微量铌

研究了以酒石酸作为络合剂,铌与铬天青S及溴化十六烷基吡啶的显色反应及应用.吸光实验表明,在盐酸溶液中,Nb(Ⅴ)-CAS-CPB形成稳定的络合物,最大吸收波长为504nm,表观摩尔系数为2.1×106L·mol-1·cm-1.铌浓度在0-2.4μg/25mL范围内遵守比耳定律,相关系数为0.9989.该法测定铌钽矿中铌,测得铌的含量为0.502％.     

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].     

Theoretical analysis and simulation of conjugate heights for dual-conjugate AO system in lidar

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.     

Quick single-photon detector with many avalanche photo diodes working on the time division

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.     

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.