荧光法直接测定环境中邻羟基苯甲酸和苯酚混合物的含量

本文研究了用荧光分光度法测定环境水中苯酚和邻羟基苯甲酸的含量碘在ＰＨ〉１１时直接测定邻羟基苯甲酸的含量,波长为λｅｘ／λｅｍ＝２８９／３３８ｎｍ,检出 为３．４ｎｇ／ｍＬ,线性范围０－６．０μｇ／ｍＬ。在ＰＨ＝６,波长为λｅｘ／λｅｍ＝２７０／２９７ｎｍ测得苯酚含量,检出限为４．０ｎｇ／ｍＬ,线性范围在０－０．８５μｇ／ｍＬ,回收率为９８－１０１％,,结果满意。     

荧光法直接测定环境水中邻羟基苯甲酸和苯酚混合物的含量

本文研究了用荧光分光光度法测定环境水中苯酚和邻羟基苯甲酸的含量,在pH＞11时直接测定邻羟基苯甲酸的含量,波长为λex/λem=289/338nm,检出限为3.4ng/mL,线性范围0-6.0μg/mL.在pH=6,波长为λex/λem=270/297nm测得苯酚含量,检出限为4.0ng/mL,线性范围在0-0.85μg/mL,回收率为98%-101%,结果满意.     

超声提取-反相高效液相色谱法测定牛膝中蜕皮甾酮

比较了超声提取与回流提取法在提取牛膝中活性成分蜕皮甾酮的提取效率，在频率为1100kHz时超声提取40min可获得稳定的提取效率。采用Shim-Pack CLC-ODS色谱柱，甲醇：水＝40：60（V／V，％）为流动相，在波长248nm下，测定牛膝中蜕皮甾酮，线性范围为2－200μg/mL（r=0．9998），检出限为0．052μg/mL（S/n=3），加标加收率为98．3％－103％。     

甘薯中微量铝的分光光度法测定

采用分光光度法与Al-CAS-CTMAB-OP四元络合物显色相结合，对甘薯中的铝含量进行了测定。A1^3 浓度在0-0．24μg／mL范围内遵守朗伯-比耳定律，相关系数r＝0．9996。回收率为91．4％-102．6％，对甘薯样品测定的结果为190．8μg／g，δ＝1．59，RSD＝0．83％(n＝5)。因甘薯中铝含量相对较高，建议在开发健康食品时应作特殊的前处理或进一步改良品种。     

组织中去甲肾上腺素的荧光测定法

本文研究了去甲肾上腺素荧光光度测定方法。测定范围在１０－１００ｎｇ则与荧光值呈良好线性关系，λｅｘ／λｅｍ＝４１０ｎｍ／５０５ｎｍ，回收率为９１．６８－９６．６５％，标准偏差平均为６．１％，本法具有准确、简便、快速等特点。     

富氧空气-乙炔火焰原子吸收光谱法测定锶

于试样溶液中加入含有0．5％镧的溶液，在富氧空气－乙炔的条件下，可有效地降低溶质干扰及电离效应，具有较高的原子化效率，可直接用于饮用水与矿泉水中锶的测定。方法的检出限为0．006μg/mL；灵敏度为0．02μg/mL。     

荧光分光光度法测定黄芪口服液中黄芪甲甙的研究

利用在硫酸条件下香草醛与黄芪甲甙的荧光反应测定黄芪口服液中的黄芪甲甙，黄芪甲甙与香草醛反应产物的最大激发波长为λｅｘ＝３６８ｎｍ，最大发射波长λｅｍ４３５ｎｍ。黄芪甲甙在０．０－３０．０ｍｇ／Ｌ范围呈良好的线性关系，最低检出限为０．３μｇ／ｍＬ，测定样品的回收率为９６．７２％－１０３．３０％。     

富氧空气-乙炔火焰原子吸收光谱法测定钡

于试样溶液中加入0．25％镧和0．5％氯化钾，在富氧空气－乙炔火焰的条件下，可有效地降低干扰及电离效应，具有较高的原子化效率，方法的检出限为0．001μg/mL，灵敏度为0．12μg/mL，可用于矿泉水中钡的测定。     

富氧空气-乙炔火焰原子吸收光谱法测定钨

试样在2％磷酸介质中，加入0．5％过硫酸钾，在富氧空气－乙炔火焰的条件下用原子吸收光谱测定钨，可有效地抑制干扰，具有较高的原子化效率，方法的检出限为0．23μg/mL，灵敏度为2．4μg/mL。     

铟(Ⅲ)-8-羟基喹啉-核酸三元荧光体系的研究与应用

基于核酸对铟(Ⅲ）-8-羟基喹啉配合物的荧光增强作用，应用铟(Ⅲ)-8-羟基喹啉为荧光探针，研究了铟(Ⅲ)-8-羟基喹啉与核酸的作用，建立了新的核酸测定方法。在最佳条件下，ctDNA、hsDNA、smDNA和yRNA的线性范围分别为0．20-1．40μg／mL、0．20-1．60μg／mL、0．10—1．40μg／mL、0．20—1．20μg／mL。检出限(3o／K)分别为0．004μg／mL，0．002μg／mL，0．002μg／mL，0．002μg／mL；测定实际样品，回收率为90．9％-103．5％。     

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.