傅里叶变换红外光谱法和紫外-可见谱线组法分析广西特产罗汉果

采用红外光谱和紫外-可见谱线组法全面分析了广西特产罗汉果,并将紫外-可见谱线组法延伸至红外光谱,采集了4种浸泡液的红外谱图。罗汉果红外光谱中出现了羟基、亚甲基、链状羧酸酯羰基、酰胺和苷键的特征吸收峰,表明其中主要含有油脂、蛋白质和甜甙等成分。4种不同极性溶剂水、乙醇、氯仿和石油醚浸泡液的紫外-可见谱线中吸收峰个数、峰形和峰位都存在很大差别,全面反映出罗汉果所含成分的整体效应。4种浸泡液的红外谱图中分别出现了不同成分的特征峰,说明水浸泡液中含有蛋白质和甜甙等极性分子,乙醇浸泡液中既含有蛋白质、甜甙,也含有油脂等脂溶性成分,氯仿浸泡液中除了含有大量油脂,还含有少量蛋白质等成分,而石油醚浸泡液中只含有油脂等脂溶性成分。     

野生植物三桠苦的营养成分

本文对野生植物三桠苦的营养成分进行了分析 ,三桠苦中含有多种营养成分 ,丰富的矿质元素和维生素及 β-胡萝卜素 ,其中至少含有 1 7种氨基酸。为开发利用该植物提供了科学依据。     

野生植物大花青藤的营养成分

对野生植物大花青藤的营养成分进行了分析 ,结果表明 ,大花青藤中含有多种营养成分 ,丰富的矿质元素和维生素及其 β-胡萝卜素。大花青藤中至少含有 17种氨基酸。为开发利用植物资源提供了科学依据。     

光谱法测定野生植物乌楣的营养成分

本文对野生植物乌楣的营养成分进行了分析 ,结果表明 ,乌楣中含有多种营养成分 ,丰富的矿质元素和维生素及β-胡萝卜素。乌楣中至少含有 1 7种氨基酸。该研究为开发利用植物资源提供了科学依据     

重整含有相异构想的认知结构

根据教育心理学的学习理论，论述了含有“相异构想”的认知结构不能正确的同化吸收物理新概念并提出了重整含有“相异构想”的认知结构的措施     

散射体系A+BC的平-振能量传递

用Alhassid与Levine所提出的动力学李代数的方法(简称A-L理论),研究了含有二级非简谐的共线散射体系A+BC的平-振能量传递问题,计算了散射过程含有主要动力学参量的跃迁矩阵和跃迁几率的解析表示式.     

斑头雁脂肪酸的气相色谱-质谱分析

采用冷冻干燥和改进的Bligh-Dyer方法提取脂肪酸,用GC-MS测定了斑头雁腿肌、胸肌组织和卵的脂肪酸组成情况,含有脂肪酸27种,均为长链脂肪酸(C14.0以上).其中饱和脂肪酸19种,占总含量的80.577％-87.701 ％;不饱和脂肪酸8种,占脂肪酸总含量的12.298％-19.423％.在斑头雁的腿肌、胸肌和卵组织中,脂肪酸组成差异不大(P＜0.05).肌肉中含有的脂肪酸种类要多于卵组织中含有的脂肪酸种类.在斑头雁组织含有10种带有甲氧基的脂肪酸,分别占腿肌脂肪酸总量的36.175％,胸肌脂肪酸的10.401％,卵脂肪酸的45.339％.     

水热法处理硫化锌沉淀引起的组成变化

用加热含有硫脲的锌的强硷性溶液的方法,获得了结晶较大的ZnS沉淀,但是,沉淀中的硫的含量要比理论值少的多。为了得到化学比的沉淀,作者曾在下面的条件下,对沉淀进行水热处理。第一种情况是把含有0.05M的ZnSO_4,0.06、0.1,和0.5M的硫脲以及含有0.5和1.0M的NaOH等溶     

含有无伴电压源电路中节点电压法的研究

介绍并比较了用节点电压法分析、求解含有无伴电压源及无伴受控电压源电路的3种方法．改进的节点电压法将受控源和独立电源一样对待,同时简化了列写方程的过程,减少了方程的数量,因此,极大地简化了问题的求解难度．对于含有超级节点的电路,此方法具有其他方法无法比拟的优越性．     

葛酒中葛根素及其挥发性成分分析

HPL C法定量测定了葛酒中葛根素的含量 ,葛酒中含有一定量的异黄酮类化合物葛根素 ,相同品牌不同生产批号葛酒中的葛根素含量相对稳定 ,可作为葛酒质量控制的分析方法。对葛酒中挥发性成分采用气相色谱 -质谱 (GC- MS)联机进行定性分析 ,鉴定出 10个组分。与白酒中挥发性成分比较 ,葛酒中除了含有己酸乙酯等白酒中具有的相同成分之外 ,还含有酸、酮等化合物 ,与传统的白酒工艺相比 ,葛酒的酿造过程具有一定特色。     

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.     

Hybrid Wavelength and Code Division Multiple Access in Optical Networks

A review of schemes for multiple access in fiber optic networks shows that a hybrid of wavelength and code division multiple access (WCDMA) combines the best features of both. In particular, the hybrid scheme retains the large information carrying capacity of wavelength division multiple access (WDMA) and flexibility of code division multiple access (CDMA). In this paper WDMA, optical CDMA (OCDMA), and WCDMA networks are discussed. In OCDMA networks, concept of incoherent and coherent coding including inverse decoding and matched filter is introduced. The delay performance of both WDMA and WCDMA networks, under the simple suboptimum access protocols based on cyclic search, is computed. It has been shown quantitatively that tuning delay significantly affects the delay performance of both WDMA and WCDMA networks. Futhermore, delay performance of WCDMA networks is always better than the WDMA networks for the same tuning delay, load, and number of users.     

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.     

Femtosecond Transform-Limited Pulse Generation by Compensating for the Linear Chirp of SPM Spectra in Dispersion Shifted Fibers

A simple technique of pulse compression, based on the linear chirp compensation of self-phase modulation (SPM) spectra in dispersion shifted fibers, is demonstrated. The optimization procedure is carried out, for a short span of a single-mode fiber, using a parabolic law, which describes the behavior of the squared output pulse width versus the pump peak power in the case of Gaussian pulses. The experimental results give a minimum pulse duration of 233 fs, which is in good agreement with the model. Shorter and coherent pulses, down to 90 fs, have been obtained by inserting an interference filter at the optical output.     

Sorting of bending magnets for the SSRF booster

The Shanghai Synchrotron Radiation Facility(SSRF)booster ring,a full energy injector for the storage ring,is deigned to accelerate the electron beam energy from 150MeV to 3.5GeV that demands high extraction efficiency at the extraction energy with low beam loss rate when electrons are ramping.Closed orbit distortion(COD)caused by bending magnet field uniformity errors which affects the machine performance harmfully could be effectively reduced by bending magnet location sorting.Considering the affections of random errors in measurement,both ideal sorting and realistic sorting are studied based on measured bending magnet field uniformity errors and one reasonable combination of bending magnets which can reduce the horizontal COD by a factor of 5is given as the final installation sequence of the booster bending magnets in this paper.     

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.