牡丹皮及种植土壤中重金属元素铅和镉的分析

测定不同产地牡丹皮及种植土壤中的重金属铅、镉含量,并分析牡丹皮与种植土壤中铅、镉含量的相关性.从安徽和山东产地采样,通过硝酸-过氧化氢-氢氟酸体系进行牡丹皮和种植土壤微波消解,用石墨炉原子吸收光谱法(GFAAS)测定牡丹皮和种植土壤中铅、镉含量.Pb元素在0-60μg/L范围内线性关系良好,回收率为102.35％,精密度RSD为1.6％ ;Cd元素在0-4μg/L范围内线性关系良好,回收率为99.85％,精密度RSD为0.7％.不同产地牡丹皮均检出重金属元素铅和镉,铅含量偏低、镉含量偏高;种植土壤中的铅、镉含量比较高,大约是牡丹皮的6-7倍.该方法具有分析速度快、测定结果的精确度和精密度高等特点.种植土壤存在着重金属污染现象,为确保药材质量,保护环境、保护药材种植土壤是非常必要的.     

火焰原子吸收光谱法测定香菇菌棒中的铜、铅、镉

用火焰原子吸收光谱法测定香菇菌棒中的铜、铅、镉含量，一次处理样品可同时测定铜、铅、镉等元素，加标回收率在92．6％-98．2％之间，方法简便、快速，结果令人满意。     

Determination of Copper, Lead and Cadmium in Pueraria thomsonii Benth.by AAS

用火焰原子吸收光谱法测定粉葛中铜的含量,石墨炉原子吸收光谱法测定粉葛中铅、镉的含量.在实验条件优化情况下,测定方法铜、铅、镉的检出限分别为:0.03mg·L-1、0.243μg·L-1和0.012μg·L-1,回收率在97.26％-105.60％之间,相对标准偏差均小于5％.实验结果表明,该方法简便、快速、灵敏.所测不同产地粉葛样品中铜、铅和镉3种重金属元素含量均在《药用植物及制剂进出口绿色行业标准》的限量指标内.     

微波消解-原子吸收光谱法测定虎耳草中的重金属

建立了虎耳草铅、镉、砷、铜、汞含量测定的方法.采用微波消解处理虎耳草药材,以原子吸收光谱法测定样品中的铅、镉、砷、铜、汞重金属元素的含量.所测不同地区虎耳草样品中除砷合格外,其他元素各有不同程度的超标.方法简便、快速、准确,能有效测定虎耳草药材中铅、镉、砷、铜、汞的含量.     

鸡精和味精中铅、镉含量的测定

采用原子吸收法测定了鸡精和味精中污染元素铅、镉的含量。结果表明,不同品牌的鸡精和味精所含铅、镉的量不同。该方法简便、快速、准确、实用。测定的线性范围为铅0.00～10.00 μg·mL-1,镉0.00～4.00 μg·mL-1。铅和镉的精密度试验的相对标准偏差分别为3.15%和4.26%,并进行了回收实验,回收率铅在96.7%～102.1%,镉在91.9%～107.6%之间。     

ICP-AES测定镉及镉合金中的杂质元素

采用ICP-AES同时测定镉及镉合金中锌、铅、铁、铜、砷、锑、锡、镍、铋、铊10种杂质元素的含量.各元素的检出限为0.0018-0.030μg/mL,相对标准偏差为1.36％-4.42％,样品加标回收率为90％-110％.测试结果表明,该法是测定镉及镉合金的简单、准确、快速的方法.     

AAS测定太行山甘草中的微量元素

利用原子吸收光谱法(AAS)测定太行山中药甘草中的重金属微量元素铜、锌、铅、镉含量,分析AAS校准曲线及各元素平均回收率和相对标准偏差(RSD).结果表明,太行山甘草中铜、锌含量较高,分别为13.70、11.59μg/g;铅、镉含量较低,分别为0.66、0.92μg/g,该法的平均回收率在98.2％-105.0％之间,相对标准偏差≤1.6％.AAS在中药检测中所得结果可靠、科学,方法简便,太行山甘草中微量元素含量丰富,重金属含量低.     

ICP-MS测定三种抗肿瘤中成药中铅镉汞砷含量

采用电感耦合等离子体-质谱(ICP-MS)法测定了三种抗肿瘤中成药(金克槐耳、华蟾素和复方苦参)中四种元素铅、镉、汞、砷的含量。结果显示,铅、镉、汞、砷四种元素在三种抗肿瘤中成药中的含量较低,均符合东南亚进口标准。其中金克槐耳中汞和砷含量略高于美国FAD药品与功能性食品要求标准,但仍符合其他标准。电感耦合等离子体-质谱法是测定中成药中铅、镉、汞、砷快速、准确的方法。     

不同产地吉祥草中重金属的含量测定

测定吉祥草中重金属及有害元素含量,比较不同产地吉祥草中的Cu、Pb、As、Cd、Hg 5种元素的含量.采用原子吸收光谱法测定铅、铜、砷含量,用原子荧光光谱法测定汞、镉含量.吉祥草药材中汞、镉、砷含量均低于国家限量标准,个别地区吉祥草药材中铜、铅含量高于国家限量标准.本文为科学地制定吉祥草药材中重金属限量标准,提高吉祥草...     

FAAS测定黑木耳中铅和镉

采用原子吸收法测定黑木耳中铅、镉的含量。同时还对一种黑木耳中的铅、镉元素进行了回收实验 ,本方法回收率在 95 %— 10 5 %之间 ,RSD% <5 % ,结果准确     

Emittance-dominated long bunches in dual harmonic RF system

The storage of long bunches for long time intervals needs flattened stationary buckets with a large bucket height. The longitudinal motion of the initially mismatched beam has been studied for both the single and dual harmonic RF systems. The RF amplitude is determined to be r.m.s wise matched. The bucket height of the single harmonic system is too small even for shorter bunch with only 20% increased energy spread. The Halo formation and even debunching can be seen after a few synchrotron periods for single particles with large amplitude. In the case of small energy spread for a cooled beam, Coulomb interaction cannot be ignored. The external voltage has to be increased to keep the r.m.s bunch length unchanged. The new voltage ratio R(N) simplifies physics for the emittance-dominated bunches with modest particle number N. For the single harmonic system, substantial amount of debunching occurs without increasing the external voltage, but very little if the RF amplitude is doubled. Results from the ORBIT tracking code are presented for the 1 GeV bunch in the HESR synchrotron, part of the GSI FAIR project.     

Speech enhancement by array crosstalk resistant ANC and spectrum subtraction

Microphone array-based speech enhancement has great importance for speech communications and speech recognition. To reduce the aperture of the microphone array and to increase the effect of the speech enhancement will greatly broaden the application areas of the microphone array. An array crosstalk resistant adaptive noise cancellation method is therefore presented. And then an improved spectral subtraction algorithm is further cascaded to obtain better enhancement results. Theoretic analysis and experiments indicate that the proposed scheme needs only a very small microphone array while it simultaneously achieves a higher SNR improvement. Besides, the proposed scheme can be used in many noisy environments and is easy for real-time implementation.     

Spectral luminescent properties of monomeric and associated molecular forms of acridine dyes in polymer matrices

M. V. Lomonosov Moscow State University, Leninskie Gory, 119899, Moscow, Russia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 2, pp. 38–46, March–April, 1995.     

ß-Correction spectrophotometry and its application to determination of a trace metal and its chelate composition: Cd(II) with dithizone

Huaibei Environmental Monitoring Center, Huaibei, Anhui Province, 235000, P. R. China. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 62, No. 6, pp. 76–80, November–December, 1995.     

An effective method for reducing speckle noise in digital holography

An effective method for reducing the speckle noise in digital holography is proposed in this paper.Different from the methods based on classical filtering technique,it utilizes the multiple holograms which are generated by rotating the illuminating light continuously.The intensity images reconstructed by a series of holograms generated by rotating the illuminating light possess different speckle patterns.Hence by properly averaging the reconstructed intensity fields,the speckle noises can be reduced greatly.Experimental results show that the proposed method is simple and effective to reduce speckle noise in digital holography.     

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.     

Energy dependence of non-linear dynamical features in e+e- collisions

A study of the dynamical fluctuation properties at various c.m. Energies in e+e- collisions is performed using the Monte Carlo method. The results suggest that, after the normalized factorial moments of 3-dimensional phase space are analyzed using an isotropical phase space partition, the NFM describing non-linear dynamical properties show a power-law scaling, I.e., the dynamical fluctuations in higher dimensional phase space are isotropic. For c.m. Energies √s≤80 GeV,the scaling exponents φq increase rapidly with the c.m. Energy and for c.m. Energies √s＞80 GeV,the φq gradually saturate.     

Voltage-controlled optical filter based on electrowetting

In this letter, we propose a voltage-controlled optical filter based on electrowetting. The device is made of a transparent cubic cell filled with two immiscible liquids having three indium tin oxide electrodes fabricated on the bottom substrate of the cell. A conductive droplet carrying a color filter is placed on the ITO electrode and the surrounding liquid is density-matched silicone oil. Under zero bias, the droplet is placed in the middle of the substrate and white light passes through the filter and we can see red light on the screen. When a voltage is applied to the device, the filter moves with the liquid based on electrowetting effect, we can see the white light on the screen. Due to the movement of the liquid, our device functions as an optical switcher. The switch time of the device is ~70 ms. The proposed device has a wide application in optical communication, electronic display, and optical switch.     

Controlled calibration method for laser induced breakdown spectroscopy

Laser induced breakdown spectroscopy (LIBS) is a potential technique for rapid analysis of samples present in solids, gases and liquids. In the last two decades it was an object of extensive studies. Controlled calibration method used to analysis the LIBS spectra is investigated. Compared with the inner calibration and calibration-free (CF) methods, this new method overcomes "matrix effect", and demonstrates a better ability to cope with the spectra. It is used to analyze natural soil, and errors of the concentration are decreased about 5%. The result shows that the new method is feasible and accurate.