高效液相色谱法测定2-苯基-4-对甲苯基-1,5-苯并硫氮杂-α-(丁二酰亚胺基)-β-内酰胺

本文采用 Hypersil- ODS2 (4 .6mm× 2 5 0 mm,5μm)色谱柱 ,乙腈 -水 (70∶ 30 )流动相 ,2 4 2 nm测定波长 ,建立了测定 2 -苯基 4 -对甲苯基 - 1,5 -苯并硫氮杂 艹卓 -α- (丁二酰亚胺基 ) -β-内酰胺高效液相色谱法。该法线性范围为 0— 0 .1mg/ m L,回归方程 A=2 .11× 10 8C- 3.10× 10 5,相关系数 r=0 .9995 ,相对标准偏差为0 .2 4 % (C=0 .0 6mg/ m L,n=5 ) ,检出限为 0 .0 5 μg/ m L。平均回收率在 97.1%— 10 2 .4 %之间。该法重现性好、灵敏度高、简单、快速、准确     

高效液相色谱法测定金盏菊中叶黄素

KNAUER Eurospher- 1 0 0 C1 8(3.9mm× 30 0 mm,4 .6 μm)色谱柱 ,以乙腈 -甲醇 -乙酸乙酯混合液为流动相 ,流速 1 .0 m L/ min;检测波长 4 6 0 nm;柱温 2 5℃ ,高效液相色谱法测定金盏菊中叶黄素含量。校准曲线法定量 ,检出限为 3.0 mg/ m L。叶黄素含量在 8— 6 4mg/ L之间线性关系良好 ,r=0 .9999,RSD=1 .4 % ,回收率在 97%— 1 0 1 %之间。本法适合叶黄素产品中叶黄素含量的测定     

高效液相色谱法测定小儿盐酸二氧异丙嗪冲剂的含量

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。     

高效液相色谱法测定富马酸异哌丙吡仑

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。     

泡腾保健品中维生素E的高效液相色谱法测定

采用反相 Apollo C1 8柱 ,甲醇 /水 (98/ 2 ,V/ V)为流动相 ,流速为 0 .8m L / min,检测波长为 2 92 nm,建立了一种测定泡腾保健品 (大豆异黄酮 VE VC)中 VE的高效液相色谱测定方法。VE在浓度为 0 .0 5 38—0 .4 30 4 mg/ m L内有良好的线性关系 ,回归方程为 y=4 .87× 1 0 6x 7.1 2× 1 0 4(r=0 .9999) ,平均回收率98.0 9%。该法简便、快速、准确。     

高效液相色谱法测定杀虫剂灭幼脲三号的含量

本文采用 Hypersil- ODS2 ( 4 .6mm× 2 50 mm,5μm)柱 ,乙腈 -水 - N,N-二甲基甲酰胺 ( 60∶ 4 0∶ 0 .1)为流动相 ,测定波长为 2 54nm,建立了测定灭幼脲三号的高效液相色谱法。该法线性范围为 2 .0— 80μg/m L,回归方程为 A=52 .4 1C+0 .1936,相关系数 r=0 .9987,精密度为 3.5% ( n=11,C=4 0μg/m L) ,检出限为 0 .0 5μg/m L。平均回收率在 96%— 10 4 %之间 ,已用于 2 5%水剂样品的测定 ,结果令人满意。     

反相高效液相色谱法测定1-(4-硝基苯)-3-(5-溴-2-吡啶)-三氮烯

ZORBAX Eclipse XDB- C8(4.6× 1 5 0 mm,5 μm)色谱柱 ,乙腈流动相 ,流速 0 .6 0 m L/min,检测波长4 2 0 nm,反相高效液相色谱法测定 1 - (4-硝基苯 ) - 3- (5 -溴 - 2 -吡啶 ) -三氮烯。该法的线性范围为 1—1 0 .0 μg/m L,线性回归方程为 A=5 .91 5 4 .4 37C,相关系数 0 .9989,相对标准偏差为 0 .8973%(C=7.2 0 μg/m L,n=5 ) ,检出限为 0 .0 2 872 μg/m L,平均回收率在 93.2 %— 1 0 2 .2 %之间。     

高效液相色谱法测定2-对甲氧基苯基-4-苯基-1,5-苯并硫氮杂-α-(丁二酰亚胺基)-β-内酰胺

应用高效液相色谱外标定量法对 2 -对甲氧基苯基 - 4 -苯基 - 1,5 -苯并硫氮杂 艹卓 -α- (丁二酰亚胺基 ) -β-内酰胺进行了测定。采用 Hypersil- ODS2 ( 4 .6mm× 2 5 0 mm,5 μm)柱 ,乙腈与水按 70∶ 30 ( V/ V)组成流动相 ,测定波长为 2 4 2 nm,该方法线性范围为 0— 0 .1mg/ m L ,回归方程 A=1.91× 10 8C- 3.82× 10 5,相关系数 r=0 .9994 ,相对标准偏差为 0 .72 %,检出限为 0 .0 5μg/ m L,平均回收率在 98.4 %— 10 1.8%之间。该法重现性好、灵敏度高、简单、快速。     

火焰原子吸收光谱法测定粤东第一温泉中钾、钠、钙、锰和锌

用火焰原子吸收光谱法测定粤东第一温泉源头水中的钾、钠、钙、锰和锌。测定结果为 :钾 2 .5 5 4mg/ L、钠 2 4 2 .0 mg/ L、钙 74 .4 0 mg/ L、锰 1 .0 78mg/ L、锌 0 .96 0 0 mg/ L,RSD1 .2 1 %— 2 .5 6 %,回收率 98.3%— 1 0 1 .1 %。     

HPLC紫外检测器测定出口月饼中的胆固醇

本文建立了一种测定出口月饼中胆固醇的方法。采用高效液相色谱 ,以 C18柱为固定相 ,甲醇 -水为流动相 ,检测波长为 2 0 8nm。方法的检出限为 0 .88mg/ 10 0 g,加标回收率为 98.7% ,RSD(n=7) <5% ,在0 .0 50— 0 .6 0 mg/ m L范围内 ,r为 0 .9991。     

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.