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1.
本文对Fe(Ⅲ)催化过氧化氢氧化新试剂糠醛缩7-氨基-8-羟基喹啉-5-磺酸(简称F7A8Q5S)进行了研究,研究结果表明试剂F7A8Q5S本身荧光很弱,被氧化后呈现强荧光,其荧光峰为λex/λem=330/405(nm),Fe(Ⅲ)的含量在0.0~40.0μg·L-1范围内与荧光强度呈良好线性,检测下限为4.68ng·L-1,由此建立了新试剂F7A8Q5S催化荧光测定痕量Fe(Ⅲ)的新方法,方法用于铸造铝合金中Fe(Ⅲ)的含量测定,结果满意.  相似文献   

2.
本文对Fe(Ⅲ)催化过氧化氢氧化新试剂糠醛缩7-氨基-8-羟基喹啉-5-磺酸(简称F7A8Q5S)进行了研究,研究结果表明试剂F7A8Q5S本身荧光很弱,被氧化后呈现强荧光,其荧光峰为λex/λem=330/405(nm),Fe(Ⅲ)的含量在0.0~40.0μg·L-1范围内与荧光强度呈良好线性,检测下限为4.68ng·L-1,由此建立了新试剂F7A8Q5S催化荧光测定痕量Fe(Ⅲ)的新方法,方法用于铸造铝合金中Fe(Ⅲ)的含量测定,结果满意.  相似文献   

3.
白慧云  郑养珍  张勇 《光谱实验室》2012,29(5):2719-2723
研究了氢化物发生-原子荧光光谱法测定自来水中痕量锌的适宜条件,着重优化仪器和试剂条件,考察了锌信号增强剂对测定的影响.结果表明,在选定的最佳测定条件下,荧光强度较大且稳定,其线性范围在0-250μg· L-1,相关系数r=0.9898,检出限为0.55μg· L-1,相对标准偏差为3.2%-7.0%,回收率为82.53%-104.6%,用于水中锌的测定,结果令人满意.  相似文献   

4.
研究了非离子表面活性剂Triton X-100存在下,新试剂联苯基双荧光酮与钼的显色反应条件,结果表明:在pH为5.1的HAc-NaAc缓冲溶液中,试剂与钼形成1∶1的红色配合物,配合物的最大吸收波长为530nm处;表观摩尔吸光系数为e=1.41×105L·mol-1·cm-1;钼含量在0-15μg/25mL范围内符合比耳定律;多数常见离子不干扰测定,方法灵敏度高,选择性好.拟定方法用于合金钢中微量钼的测定,结果满意.  相似文献   

5.
环糊精锌(Ⅱ)荧光试剂在水分析中的应用研究   总被引:1,自引:0,他引:1  
合成高水溶性的锌()荧光试剂-修饰环糊精的N-(8-对氨基苯磺酰)胺基喹啉(HQAS-1-CD)。该试剂在水溶液中与Zn2+形成2:1配合物而使荧光增强,并且碱金属或碱土金属离子几乎不干扰Zn2+的荧光。利用此配位反应建立了一个荧光测定痕量锌的新方法,测定锌的线性范围为0—13μg/L,检出限0.57μg/L,方法成功的应用于矿泉水中痕量锌的测定。  相似文献   

6.
对曲克芦丁在胶束体系中的荧光性质进行了研究。实验发现在NaAc-HAc缓冲体系中,曲克芦丁自身具有较弱的内源性荧光,加入适量的表面活性剂十二烷基苯磺酸钠-6(SDBS-6),可使曲克芦丁与SDBS-6形成胶束配合物,体系微环境发生改变,使荧光发射强度显著增强,荧光增强程度与曲克芦丁的含量在一定范围内呈良好的线性关系。据此提出了基于SDBS-6增敏胶束荧光光谱法测定微量曲克芦丁的新方法。对测定条件进行了详细研究,结果表明: 在pH 5.53的NaAc-HAc缓冲体系中,当最大激发波长λex=350.0 nm,最大发射波长λem=456.3 nm时,方法线性范围为1.6×10-6 mol·L-1~8.0×10-10 mol·L-1,检出限1.1×10-10 mol·L-1,相对标准偏差为1.7%(n=11,c=6.0×10-7 mol·L-1)。方法用于片剂和注射液中曲克芦丁的测定,回收率为98.5%~100.4%,结果令人满意。  相似文献   

7.
盐酸丁卡因与赤藓红的荧光猝灭反应及其分析应用   总被引:1,自引:0,他引:1  
在pH 4.0的弱酸性介质中,盐酸丁卡因(TA·HCl)与赤藓红(ET)形成1∶1的离子缔合物,导致赤藓红溶液荧光猝灭。当分别于最大激发/最大发射(λexem)525 nm/556 nm进行测量时,荧光猝灭值(ΔF)与TA·HCl浓度在0.28~4.8 μg·mL-1范围呈良好的线性关系。该方法灵敏度高,检出限为0.083 μg·mL-1。考察了共存物质的影响,表明方法有良好的选择性。据此发展了一种高灵敏、简便快速测定微量TA·HCl的新荧光分光光度法。该法用于人血清及尿样中盐酸丁卡因的含量测定,结果满意。文章还研究了反应体系的荧光特性,并结合量子化学AM1计算对荧光猝灭机理进行了讨论。  相似文献   

8.
合成了新化合物双水杨醛草酰二腙,根据元素分析及红外光谱确定了其结构,研究了该化合物与锌离子在溶液中的荧光反应.结果表明,以乙醇为溶剂,酸度为7.00时,该化合物与锌离子生成配合物的荧光强度最强.体系的荧光强度与锌离子的浓度在0~65.0μg·L-1的范围内呈良好的线性关系,检测下限达0.3μg·L-1.通过对16种常见离子在该体系中的干扰的实验研究,证明双水杨醛草酰二腙对锌离子有良好的选择性.对含锌营养食盐及人发中的锌进行了测定,结果满意.  相似文献   

9.
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.  相似文献   

10.
基于表面活性剂的浊点现象,建立了以双硫腙为螯合剂、Triton X-114为表面活性剂的浊点萃取-石墨炉原子吸收光谱法测定痕量铅的新方法。研究了溶液pH值、试剂浓度、平衡温度和加热时间等实验条件对浊点萃取及测定灵敏度的影响。以4 000 r·min-1离心15 min使分相, 分相后的溶液在冰水浴中冷却至接近0 ℃,然后反转离心管弃去水相,用0.1 mol·L-1 HNO3-甲醇溶液定容至0.5 mL, 溶液以磷酸二氢铵及硝酸镁为基体改进剂由石墨炉原子吸收分光光度法进行测定。在pH 8.0和0.05% Triton X-114及20 μmol·L-1双硫腙存在下, 富集10 mL样品溶液,铅的检出限为0.089 μg·L-1,富集倍率为19.1,所得工作曲线回归方程为A=0.0261c(μg·L-1)+0.010 6,线性范围0.1~30 μg·L-1,相关系数r为0.998。方法用于环境水样中测定痕量铅的测定,获得满意结果。  相似文献   

11.
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.  相似文献   

12.
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.  相似文献   

13.
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.  相似文献   

14.
The performance of port/starboard discrimination of dual-line array will be seriously degraded when the space between the two line arrays of the dual-line array is mismatched. The directivity function of the delay-sum and delay-subtract beamforming is deduced and the port/starboard discrimination of the delay-sum and delay-subtract beamforming is also studied both under the ideal status and the status under which the space between the two line arrays of the dual-line array is mismatched. Analysis results show the delay-subtract beamforming has better performance of port/starboard discrimination. At last, the sea trial results demonstrate the theoretical results.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
18.
With a novel light-weight and absolutely calibrated ultraviolet (UV) spectrometer, UV skylight radiances and O3 slant column densities are measured by balloon-borne limb measurements in Xinjiang area, China. UV skylight radiances measured at the height of 31 km are compared with the results from Modtran in the wavelength range from 290 to 420 nm. O3 slant column densities are derived from radiance spectra in the Huggins bands (320 - 335 nm) using differential optical absorption spectroscopy method. And the parameter exhibits a good correlation with the same value simulated by radiative transfer model (Tracy). The O3 profile simultaneously measured by an O3 sonde is used as input in Tracy calculations. The O3 sonde is launched on the same balloon.  相似文献   

19.
For breaking through the sensitivity limitation of conventional surface plasmon resonance (SPR) biosensors, novel highly sensitive SPR biosensors with Au nanoparticles and nanogratings enhancement have been proposed recently.But in practice, these structures have obvious disadvantages.In this study, a nanohole based sensitivity enhancement SPR biosensor is proposed and the influence of different structural parameters on the performance is investigated by using rigorous coupled wave analysis (RCWA).Electromagnetic field distributions around the nanohole are also given out to directly explain the performance difference for various structural parameters.The results indicate that significant sensitivity increase is associated with localized surface plasmons (LSPs) excitation mediated by nanoholes.Except to outcome the weakness of other LSP based biosensors, larger resonance angle shift, reflectance amplitude, and sharper SPR curves' width are obtained simultaneously under optimized structural parameters.  相似文献   

20.
Novel polymer distributed feedback(DFB)gratings are fabricated based on photopolymerization to reduce lasing threshold of polymer lasers.A photopolymer formulation sensitive to 355-nm ultraviolet(UV)light is proposed for the fabrication of polymer gratings and it can be used to form polymer films by spin-coating process.A very low surface-relief depth ranging from 12.5 to about 1.0 nm has been demonstrated with a refractive-index modulation of about 0.012.The experimental results indicate that such polymer gratings have promising potentials for the fabrication of low-order DFB organic semiconductor lasers.  相似文献   

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