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FAAS法测定硫酸中的铁和锌 总被引:2,自引:1,他引:1
本文建立了火焰原子吸收光谱法测定硫酸中铁和锌的方法,确定了最佳仪器工作条件和样品处理方法。在选择好的实验条件下,测定铁的特征浓度为0.014μg/mL/1%吸收;测定锌的特征浓度为0.002μg/mL/1%吸收。回收率分别为铁98.8%-103.4%,锌92.5%-98.6%。 相似文献
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用Air-C2H2火焰原子吸收光谱法测定银锌电池醋酸纤维素膜中铁含量.介绍了样品的消化处理条件和铁最佳测定条件,铁浓度0-10μg/mL范围内呈良好线性关系.该方法的灵敏度好,准确度与精密度均能满足银锌电池研制工作的要求.测定样品中铁含量相对标准偏差均小于1.0%(测定次数n=6).标准加入回收率均在97.3%-98.0%(n=6)范围.适用于银锌电池醋酸纤维素膜中铁的测定. 相似文献
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水果、蔬菜中维生素C含量的测定——紫外分光光度快速测定方法探讨 总被引:23,自引:0,他引:23
本文利用维生素C具有对紫外产生吸收和对碱不稳定的特性,建立了紫外分光光度快速测定水果、蔬菜维生素C含量的新方法.维生素C浓度在1.00-12.0μg/mL范围内与吸收值呈良好的线性关系;检出限为0.014μg/mL;加标回收率在97.9%-99.0%之间.该法操作简单,结果准确,应用于维生素C含量的测定,结果令人满意. 相似文献
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用硝酸、高氯酸混合酸消解样品,原子吸收光谱法测定河南太行山区的花椒及椒皮、椒籽中铜、锌、铁、锰的含量,并对其结果进行了分析.结果显示:各元素在实验范围内,线性关系良好,回收率在92%-103%之间.花椒及椒皮、椒籽中均含有微量元素,花椒中铜、锌、铁、锰的含量分别为11.571、90.868、18.818、78.851μg·g-1,其中铁、锰含量丰富.铜、锌、铁的分布量为椒籽>椒皮;锰的分布量为椒皮>椒籽.测定结果为探讨花椒的高药用价值提供了有力的证据,椒籽中铜、锌、铁含量高于椒皮,应该大力开发利用. 相似文献
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建立湿式消解-ICP-AES测定猪组织器官中7种金属元素含量.对猪肉、猪肝、猪肚15份样品,采用湿式消解法进行前处理,利用ICP-AES测定铁、锰、铜、锌、镉、铅、铬7种金属元素含量.方法检出限为0.230-3.501μg/L、线性范围为0.01-6.00μg/mL、相关系数为0.99961-0.99997、加标回收率为90.4%-96.8%、相对标准偏差为1.03%-3.12%.经实际检测,猪产品中含有丰富的人体必需的金属元素铁、锌、铜,特别是猪肝中的铁和锌含量较高,铁最高达到160.3mg/kg,锌最高达到113.4mg/kg.结果显示3种猪组织器官是人体补充铁、锌金属非常有益的营养食品. 相似文献
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流动注射在线离子交换柱富集-火焰原子吸收光谱法测定钨矿中的铜、锌和铅 总被引:5,自引:0,他引:5
建立了流动注射在线离子交换柱富集-火焰原子吸收光谱法测定钨矿中的铜、锌和铅的方法,样品经盐酸和硝酸分解后,加入5%宁可辛溶液使样品中大量的钨呈钨酸析出,样品中一般的伴生元素都可形成可溶性化合物与钨酸分离,之后采用流动注射在线富集与原子吸收联用技术,分别加入浓度依次递增的3种元素的标准溶液,用空气-乙炔火焰原子吸收连续测定Cu、Zn和Pb的含量。建立了优化的仪器工作条件,并对可能存在的元素进行干扰试验。方法检出限Cu为0.001μg/mL、Zn为0.001μg/mL、Pb为0.01μg/mL,相对标准偏差Cu为2.7%、Zn为3.6%、Pb为1.9%,加标回收率为96%—106%。 相似文献
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为了提高LED光源色温和亮度的调节精度和准确度,结合色温由低向高变化时光色所呈现的渐变特点,提出了一种低色温白光LED灯珠、高色温白光LED灯珠加红绿蓝光LED灯珠补偿式调光的方法.将色温分成三个部分进行调节,每个部分选用不同的LED灯珠组合来进行调光.实验结果表明:不同组合情况下的LED光源的初始输出色温相对于目标值的偏差范围在1%以内;亮度可以在保证色温不变的情况下独立进行调节,初始输出值与目标值的偏差范围在1%以内;经过微调之后可以达到目标值;达到了色温和亮度独立调节的要求;光源发光稳定,不会因为长时间工作而影响调节精度. 相似文献
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A technique combining image processing and laser interferometry for visualizing and detecting the deformation of transparent cylindrical and spherical sample is proposed. This deformation includes geometric deformation such as volume transition in profilometry and physical deformation such as refractive index change in tomography. Phase contour lines are used for quantitative analysis and graphical representation of the deformation. This method allows us to visually detect the spatial variation of the deformation field and to evaluate the test quality such as misalignment of optical system. A theoretical analysis using phase contour map to characterize the deformation field is described in detail. A method using phase contour map to qualify the interferometric test is proposed. Analysis of test examples is carried out. Suggestions on using phase contour line method to ameliorate test system design are finally discussed. 相似文献
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Mario Rabinowitz 《International Journal of Theoretical Physics》2009,48(3):706-722
Discrepancies and accords between quantum (QM) and classical mechanics (CM) related to expectation values and periods are
generally found for both the harmonic oscillator (SHO) and a free particle in a box (FPB), which may apply generally. These
indicate non-locality is expected throughout QM. The FPB energy states violate the Correspondence Principle. Previously unexpected
accords are found and proven that 〈x
2〉
CM
=〈x
2〉
QM
and τ
CM
=τ
QMb
(beat period i.e. beats between the phases for adjoining energy states) for the SHO for all quantum numbers, n. However, for the FPB the beat periods differ at small n. It is shown that a particle’s velocity in an infinite square well varies, no matter how wide the box, nor how far the particle
is from the walls. The quantum free particle variances share an indirect commonality with the Aharonov-Bohm and Aharonov-Casher
effects in that there is a quantum action in the absence of a force. The concept of an “Expectation Value over a Partial Well
Width” is introduced. This paper raises the question as to whether these inconsistencies are undetectable, or can be empirically
ascertained. These inherent variances may need to be fixed, or nature is manifestly more non-classical than expected. 相似文献
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We present a systematic study of the effect of methyl substitution on iso- and alloxazines in acetonitrile solutions. Substitution patterns have profound effects on both spectral and photophysical properties, with fluorescence quantum yields varying by more than an order of magnitude. TD-DFT calculation were used for the first time to correlate electronic structure changes with the substitution patterns, with good agreement between calculated and theoretical band positions and oscillator strengths. Both n-pi* and pi-pi* states in these compounds are predicted, with the oscillator strengths indicating that only the pi-pi* states should be observable in the absorption spectra. Substitution patterns are shown to be responsible for energy order inversion between these states. 相似文献
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A. Dutta 《辐射效应与固体损伤》2013,168(2):92-96
In this letter, we illustrate the importance of fluid dynamics research by considering two particular areas of study: nano- and micro-scale fluid and plasma dynamics. We show how improved scientific knowledge of nano- and micro-fluid dynamics can significantly enhance our future. Application is also discussed regarding environmental aspects. 相似文献
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国外超导材料技术研究政策和方向 总被引:1,自引:1,他引:0
超导材料技术是21世纪具有战略意义的高新技术,极具发展潜力和市场前景。世界各发达国家纷纷制定研发计划,给予高度重视和大力支持,加快超导材料技术的基础研究和产业化发展。主要从美国、日本、欧洲国家、韩国等国家的相关研发计划、政策以及主要科研机构的研发概况出发,阐明目前国外超导材料技术的研究政策和方向。 相似文献
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基于OpenGL和大气传输光学分析的3维全数字仿真是激光跟瞄系统的重要研究手段。为提高跟踪和瞄准精度,从激光跟瞄仿真系统整体出发,研究了目标成像中的投影变换、成像与跟踪的关系、高精度跟踪现有算法的控制过程仿真等内容,并提出了基于大视口、目标大气传输图像序列的跟瞄仿真技术。说明了仿真系统中跟瞄精度分析的特点。就某仿真场景,设计了“头部顶点”和“两点提取”两种跟瞄方法,在不同大气湍流条件下得到了它们的跟瞄精度,说明应用该激光跟瞄仿真系统,能够预先设计、测试和验证一些跟瞄方法,帮助进行算法分析和改进,从而提高工作效率和节约成本。 相似文献
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本文总结了计算黑克、布劳、及伯曼 温采尔代数在各种工数链下诱导及分导系数的线性方程方法(LEM)。特别强调了关于A,B,C,D型李代数及其量子情形与其中心代数之间的舒尔 魏尔 布劳双关性关系。这一关系使我们能够利用相应中心代数的诱导及分导系数计算出经典李代数及其量子情形的耦合与重新耦合系数。讨论了从该方法得到B,C,D型李代数不可约表示克罗内克积分解的应用。基于LEM还得到了处理对应于置换群CG系列问题的黑克代数张量积的方法。 相似文献
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Valentina Simonetti Jason Y. Park Nicholas J. Panaro Larry J. Kricka 《Journal of nanoparticle research》2008,10(2):365-368
Nylon nanorods and nanotubes (200 nm diameter) were fabricated by the membrane wetting technique (solvent and melt wetting)
from a range of nylons (6; 6,6; 6,9; 6,10; 6,12; 11; 12, 6(3)T) and nylon blended with different dyes (Nylon Cast Blue, Nylon
6/6 Black) or with molybdenum disulfide (Nylon cast MDS). The 65-μm long nylon nanotubes and nanorods were characterized by
scanning electron microscopy. The nanoscale nylon 6,6 served as an effective high surface area alternative to a nylon membrane
as a solid support in a chemiluminescent assay for nylon-bound biotinylated nucleic acids based on streptavidin- alkaline
phosphatase and chemiluminescent detection of the bound alkaline phosphatase label with the dioxetane substrate, CDP-Star.
Layer-by-layer deposition of the cationic polymer (Sapphire-II™; Tropix) onto the nylon 6,6 nanostructures prior to UV-cross-linking
with biotinylated DNA resulted in further enhancement of binding and detection of biotinylated DNA. 相似文献