某新型液体推进剂组分含量的测定

建立了三种方法测定某新型液体推进剂组分含量,分别是液相色谱紫外检测器法(HPLC-UVD)、液相色谱示差折光检测器法(HPLC-RID)、核磁共振法(NMR).HPLC-UVD法测定推进剂中硝酸酯(A)、安定剂(B)的含量,实验相对标准偏差(RSD)(n=7)分别为0.30%、0.55%.回收率分别是99.2%-100.7%、99.1%-100.8%.HPLC-RID法测定A、B、安定剂(C)的含量,RSD(n=6)分别是0.05%、0.32%、0.17%,回收率分别为99.81%-100.17%、100.28%-100.49%、99.55%-100.79%.NMR法测定以、B、C的含量.RSD(n=12)分别是0.21%、0.32%、0.11%,回收率分别为98.8%-101.6%、98.7%-102.0%、98.2%-101.2%.     

IR-UV联合法测定固相微萃取涂层中单体含量

合成了作为固相微萃取涂层的苯乙烯-丙烯酸丁酯-乙烯基三乙氧基硅氧烷三元共聚物。采用红外光谱(IR)和紫外光谱(UV)相结合的方法测定了聚合物中苯乙烯和丙烯酸丁酯的含量。由IR法测得样品中二者的摩尔比。采用双波长紫外光谱法测得苯乙烯的含量。由苯乙烯与丙烯酸丁酯的摩尔比及苯乙烯的含量得出样品中丙烯酸丁酯含量,进而得出乙烯基三乙氧基硅氧烷的含量。苯乙烯与丙烯酸丁酯的摩尔比测定的外标曲线方程为A_r=0.114m_r+0.032,相关系数r2=0.999 3;苯乙烯含量测定的标准曲线方程为ΔA=0.078 6c+0.081 2,相关系数r2=0.998 9。苯乙烯含量测定的相对标准偏差(RSD)为0.41%,加标回收率为97.8%～104.0%;丙烯酸丁酯含量测定的相对标准偏差(RSD)为0.39%,加标回收率为97.1%～99.6%。     

蒙药匝迪-5和八味三香散总黄酮含量的测定

本文用70%乙醇分别提取了匝迪-5和八味三香散的类黄酮物质。分别用活性炭、活性白土等脱色、除杂,用硝酸铝-亚硝酸钠方法对黄酮的含量进行了测定,求得其校准曲线的回归方程为y=0.0094x-0.0023,r=0.9995,线性范围在3.08—21.56μg/mL。匝迪-5总黄酮含量为2.45%,平均回收率98.6%,相对标准偏差为0.65%(n=5);八味三香散总黄酮含量为4.5%,平均回收率为99.6%,RSD=0.87%(n=5)。     

纤维素类芒属草本能源植物品质近红外光谱快速检测技术研究

我国生物质能源产业近年来得到快速发展,但对能源草的研究还处于初级阶段,如果能建立全面的能源植物木质素、纤维素、半纤维素的近红外预测模型数据库,将有助于优良品种的筛选、能源植物能用性能的评价及生物质能源产业在线控制。本研究采用傅里叶变换近红外光谱(FT-NIR)技术结合偏最小二乘法(PLSR)建立了荻、南荻、奇岗、芒四种芒属能源植物品质指标(纤维素,半纤维素,木质素和灰分)近红外预测模型,并在此基础上研究了样本粒度对模型的影响。研究结果表明：(1)四种芒属能源植物茎秆中纤维素,半纤维素和木质素含量误差均方根(RMSECV)分别为1.35％(R2=0.88),0.39%(R2=0.91)和0.35%(R2=0.80),叶片中纤维素,半纤维素和木质素含量误差均方根(RMSECV)分别为0.72%(R2=0.88),0.85%(R2=0.85)和0.44 (R2=0.87),所建的纤维素,半纤维素和木质素的近红外校准模型在预测未知样品含量时效果较好,但灰分含量预测效果不理想;(2)2和0.5 mm粒度样品所建近红外模型均满足样品检测精度要求,但考虑到时间和人工成本,建议在工厂对能源植物原料品质进行分析时,采用2 mm样品建模。     

氢化物发生-原子荧光光谱法间接测定牛奶中Cr(Ⅲ)和Cr(Ⅵ)

在盐酸浓度为3.0 mol·L-1介质中,Cr(Ⅵ)把As(Ⅲ)氧化成As(Ⅴ),利用氢化物发生-原子荧光光谱法(HG-AFS)测定剩余As(Ⅲ)的含量,间接得到Cr(Ⅵ)的含量。基于相同原理,结合高锰酸钾氧化Cr(Ⅲ)来测定Cr(Ⅲ)含量。研究了溶样方法和共存离子可能引起的干扰,优化了仪器工作条件、酸度及其他影响因素。在最佳条件下,铬含量在4.0～20 μg·L-1范围内线性关系良好,方法检出限为2.5 μg·L-1;将方法应用于牛奶样品分析,相对标准偏差(RSD,n=6)为1.6%～2.7%。加标回收率为96.5%～104.2%。     

高压消解-紫外分光光度法测定红花中的重金属

采用高压消解-紫外分光光度法,建立了测定淮红花中的重金属含量的方法。结果表明:此法铅含量在0—40μg范围内,与吸光度线性关系良好,r=0.9989。淮红花中重金属含量为18.71μg/g,符合国家标准,平均加标回收率为97.82%,RSD=2.93%(n=5)。高压消解法的使用,进一步提高了测定方法的准确性和便捷性,此法可用于中药中重金属含量的检测。     

穿心莲中总黄酮含量的测定

以芦丁为对照品,NaNO2-Al(NO3)3-NaOH体系为显色剂,利用分光光度法测定了穿心莲中的总黄酮含量.确定了总黄酮提取方法、显色剂浓度和显色时间等.回归方程为A=0.00652 11.0329C,相关系数r=0.9997.平均回收率为104.20%,RSD=1.85%(n=5).本法操作简便,可行,重现性好.     

聚丙烯酸钠增敏抑制高碘酸钠氧化夜蓝褪色光度法测定痕量锡

建立了聚丙烯酸钠增敏抑制高碘酸钠氧化夜蓝褪色光度法测定痕量锡的新方法。该方法基于聚丙烯酸钠增敏锡 ( )抑制高碘酸钠氧化夜蓝褪色反应 ,在最佳条件下 ,锡 ( )的含量在 0 .2 0— 2 .0 μg/L范围内与 ΔA值呈线性关系 ,其校准曲线的回归方程 ΔA=0 .0 0 788+ 0 .10 9CSn( ) (μg/L) ,r=0 .9992 ,检出限(L D) =1.1× 10 -11g/m L。本方法用于测定人发样品和水样中的锡含量 ,其相应的回收率为 10 0 .3%和10 0 .0 %。相对标准偏差为 3.4 %和 3.2 %。     

HPLC测定羟丙基环糊精/蒿甲醚包合物中蒿甲醚

建立用HPLC测定蒿甲醚-羟丙基-β-环糊精包合物中蒿甲醚含量的方法。色谱柱为Lichrospher C18柱,乙腈-水(60:40,V/V)为流动相,检测波长210nm。包合物中蒿甲醚的含量在5—35μg范围内与峰面积呈线性关系(r=0.9998)。平均加样回收率为97.87%,RSD为0.66%(n=5)。     

积雪草总黄酮提取工艺和含量测定研究

确定积雪草总黄酮最佳提取工艺和含量测定方法,采用微波辅助法提取积雪草中的黄酮类化合物,通过正交实验确定了最佳提取工艺.分别以槲皮素和山奈酚为对照,采用紫外分光光度法在320nm处测定积雪草全草中的总黄酮.最佳工艺条件:提取次数3次,辐射时间20s,固液比1:10,功率480W.按最佳工艺条件提取总黄酮含量为8.40mg/g.回归方程为(槲皮素):y=29.993C+0.027,相关系数r2=0.9982,精密度和稳定性试验RSD分别为0.265%和0.172%(n≥6),平均加样回收率为99%,RSD=1.51%(n=5).回归方程为(山奈酚):y=36.928C+0.0178,相关系数rz=0.9991,精密度和稳定性试验的RSD分别为0.231%和0.190%(n≥6),平均加样回收率为99%,RSD=0.714%(n=5),样品的稳定性试验RSD为0.218%(60min).选择的最佳工艺对提取积雪草全草总黄酮确为最佳.用槲皮素或山奈酚标准品,采用紫外分光光度法,操作简便,结果准确,灵敏度高,重复性好,为积雪草全草中总黄酮含量测定的一种切实可行的方法.     

Guided-Wave Two-Dimensional Acousto-Optic Scanner Using Proton-Exchanged Lithium Niobate Waveguide

Two-dimensional scanning of a 0.6328 mum guided-light beam has been realized using noncolinear acousto-optic (AO) coplanar Bragg diffraction together with colinear AO guided-mode to substrate radiation-mode conversion in a Z-cut Xpropagation LiNbO3 proton-exchanged (PE) waveguide. The two surface acoustic (SAW) waves utilized are at the center frequencies of 500 and 200 MHz, propagating in the Y and X axes, respectively. Two-dimensional scanning of approximately 720 resolvable light beam spots, namely, 18 40 (horizontal vertical) scanning, has been demonstrated using a light beam of 1.0 mm aperture. The total number of resolvable beam spots can be greatly increased from 720 by simply utilizing SAW transducers of larger bandwidth and a light beam of greater aperture. It should also be possible to significantly increase the diffraction efficiency from 3 % by optimizing the parameters of the PE waveguide and the SAWs.     

Effect ofγ-radiation on the spectral luminescence characteristics of impure cadmium tungstate crystals

Results of a study of the effect of γ-radiation on the spectral luminescence properties of cadmium tungstate crystals doped with silver, bismuth, and molybdenum cations are presented. Spectral characteristics of the nondnnnoped crystals are briefly described. Absorption and photo and X-ray luminescence spectra of the crystals taken before and after exposure to γ-radiation (5.5·10⁴ Gy) are compared. It is found that the spectral characteristics of the crystals doped with silver, bismuth, and molybdenum cations do not change markedly after the exposure. The relation between the type of impurity-induced defects, individual characteristics of the impurity cations, and the character of the effect of γ-radiation on the spectral luminescence properties of impure crystals is analyzed (preliminarily). Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 55–60, January–February, 1997.     

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.     

Measurement of nonlinear coefficient of optical fiber based on small chirped soliton transmission

We measure the waveform and phase curves of short optical pulses before and after transmission over different lengths of fibers by use of the pulse analyzer with the frequency-resolved optical gating (FROG),and numerically simulate pulse evolution under the experimental conditions.The nonlinear coefficient of the fiber is given by comparing the experimental results with the numerical ones.Difference between the experiment and numerical simulation is analyzed.     

Resonance scattering of canonical elastic shells in absorbing fluid medium

Resonance scattering of elastic spherical shell and cylindrical shell while the surrounding fluid medium has absorption is studied. The normal mode solution derived using exact elastic theory and the separation of variables is still applicable. However, the scattering form function has to be modified for the absorbing medium, otherwise the unreasonable result would be obtained. The backscattering form function in the absorbing medium is redefined, and the form function of elastic spherical and cylindrical shell with vacuum or solid matter filled is calculated in various absorption conditions. The results show that the absorption of surrounding fluid leads to notable attenuation of the coincidence resonances in the mid-frequency, but it has a little influence on the low-frequency resonance scattering induced by the filler inside the shell.     

Single-beam self-referenced phase-sensitive surface plasmon resonance sensor with high detection resolution

A versatile and low-cost single-beam self-referenced phase-sensitive surface plasmon resonance(SPR)sensing system with ultra-high resolution performance is presented.The system exhibits a root-mean-square phase fluctuation of ±0.0028.over a period of 45 min.i.e.a resolution of±5.2×10-9 refractive index units.The enhanced performance has been achieved through the incorporation of three design elements:a true single-beam configuration enabling complete self-referencing so that only the phase change associated with SPR gets detected,a differential measurement scheme to eliminate spurious signals not related to the sensor response,and the elimination of retardation drifts by incorporating temperature stabilization in the liquid crystal phase modulato .Our design should bring the detection sensitivity of non-labeling SPR biosensing closer to that achievable by conventional fluorescence-based techniques.     

Influences of SiO2 protective layers and annealing on the laser-induced damage threshold of Ta2O5 films

Ta2O5 films are prepared on BK7 substrates with conventional electron beam evaporation deposition.The effects of SiO2 protective layers and annealing on the laser-induced damage threshold (LIDT) of the films are investigated.The results show that SiO2 protective layers exert little influence on the electric field intensity(EFI)distribution,microstructure and microdefect density but increase the absorption slightly.Annealing iS effective on decreasing the microdefect density and the absorption of the films.Both SiO2 protective layers and annealing are beneficial to the damage resistance of the films and the latter is more effective to improve the LIDT.Moreover,the maximal LIDT of Ta2O5 films is achieved by the combination of SiO2 protective layers and annealing.     

A stereo matching algorithm using multi-peak candidate matches and geometric constraints

Gray cross correlation matching technique is adopted to extract candidate matches with gray cross correla- tion coefficients less than some certain range of maximal correlation coefficient called multi-peak candidate matches. Multi-peak candidates are extracted corresponding to three closest feature points at first. The corresponding multi-peak candidate matches are used to construct the model polygon. Correspondence is determined based on the local geometric relations between the three feature points and the multi-peak candidates. The disparity test and the global consistency checkout are applied to eliminate the remaining ambiguous matches that are not removed by the local geometric relational test. Experimental results show that the proposed algorithm is feasible and accurate.