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71.
光纤陀螺捷联系统标定测试软件的设计与开发 总被引:2,自引:0,他引:2
基于 windows 平台,采用 VC 6.0 开发了光纤陀螺捷联惯组标定测试软件,着重阐述了该软件的设计思想和关键技术的实现。该软件实现了对光纤陀螺捷联组合误差系数的标定与测试,为光纤陀螺捷联系统标定测试提供了方便,具有很强的工程实用价值。 相似文献
72.
Sanjukta A. Kumar Neha Thakur Harshala J. Parab Shailaja P. Pandey Rakesh N. Shinde Ashok K. Pandey Sangita D. Kumar A.V.R. Reddy 《Analytica chimica acta》2014
A visual strip has been developed for sensing iron in different aqueous samples like natural water and fruit juices. The sensor has been synthesized by UV-radiation induced graft polymerization of acrylamide monomer in microporous poly(propylene) base. For physical immobilization of iron selective reagent, the in situ polymerization of acrylamide has been carried out in the presence of 1,10-phenanthroline. The loaded strip on interaction with Fe(II) in aqueous solution turned into orange red color and the intensity of the color was found to be directly proportional to the amount of Fe(II) in the aqueous sample. The minimal sensor response with naked eye was found for 50 ng mL−1 of Fe in 15 min of interaction. However, as low as 20 ng mL−1 Fe could be quantified using a spectrophotometer. The detection limit calculated using the 3s/S criteria, where ‘s’ is the standard deviation of the absorbance of blank reagent loaded strip and ‘S’ is the slope of the linear calibration plot, was 1.0 ng mL−1. The strip was applied to measure Fe in a variety of samples such as ground water and fruit juices. 相似文献
73.
We describe a novel solution-based method for the determination of dissolved organic matter (DOM) relying on the formation of silver nanoparticles (AgNPs) via photo-stimulated reduction of silver ions by humic and fulvic acids. The method is based on natural driven formation of nanoscale materials yielding a direct relationship between DOM concentration and AgNPs formation. The aqueous dispersion of the formed AgNPs show strong and uniform UV–Vis absorption bands between 450 and 550 nm irrespectively of DOM nature and properties (i.e. humic or fulvic acids). The ensuing chromatic shift accompanying the appearance of the new absorption bands is easily conceivable by a simple spectrophotometer and the bare eye, holding great promise for the on-site, instrumental-free screening of DOM levels. Under the optimum experimental conditions the determination of DOM was successfully demonstrated to various water samples with high sensitivity (<1.0 mg L−1), satisfactory recoveries (87.5–123.5%) and reproducibility (5.87–6.73%). 相似文献
74.
75.
Mingjin Wang 《Journal of Mathematical Analysis and Applications》2011,379(1):461-468
In this paper, we derive an expectation formula of a random variable having distribution W(x;q). As applications of the expectation formula, we give a transformation formula and an expansion of Sears? transformation formula. 相似文献
76.
Basic hypergeometric series identities are revisited systematically by means of Abel's lemma on summation by parts. Several new formulae and transformations are also established. The author is convinced that Abel's lemma on summation by parts is a natural choice in dealing with basic hypergeometric series. 相似文献
77.
运输问题悖论及其研究 总被引:6,自引:0,他引:6
提出了运输问题的奇特现象——运输问题的悖论,讨论了运输问题悖论出现的条件,最后指出了研究运输问题悖论的现实意义. 相似文献
78.
Irina M. Solomentseva Sandor Barany John Gregory 《Colloids and surfaces. A, Physicochemical and engineering aspects》2003,230(1-3):117-129
The action of pre-hydrolysed coagulants such as basic aluminium chloride (BAC) and sulphate (BAS) in water treatment is of considerable practical and fundamental interest. Variables such as working solution concentration, dosage, pH and ionic strength are known to be important. We have investigated the influence of these variables on the ζ-potential and degree of hydration of hydrolysis products of basic aluminium sulphate samples with different basicities. The products were characterised by a timed ferron complexation procedure, giving information on the degree of polymerisation of the BAS samples. Electrokinetic measurements showed that the ζ-potentials of hydrolysis product particles were consistently higher (more positive) for the higher basicity samples. The ζ-potential decreased with increasing concentration of the working solution and with increased dosage.
The degree of hydration of the hydrolysis products was investigated using the spin-lattice relaxation time of protons of water molecules bound to their surfaces. This was found to decrease with increasing basicity of BAS, indicating a greater degree of hydration. Since this effect is expected to decrease ζ potential by a displacement of the electrokinetic shear plane, the observed increase in ζ is probably due to the adsorption of highly charged positive hydrolysis products of BAS. 相似文献
79.
上海股市波动的预测方式和模型 总被引:1,自引:1,他引:0
刘凤芹 《数学的实践与认识》2004,34(10):22-26
探讨基于 SV类模型的上海股市波动的预测方式和模型问题 .比较了 SV( stochastic volatility)类模型 (包括基本 SV模型和 ASV模型 )在两种不同方式下的预测效果 ,并将基本 SV类模型的预测效果与 ASV模型 ,以及其他常用模型做了比较 .结果表明 :SV类模型在两种预测方式下的预测效果存在一定的差异 ;基本 SV模型对于上海股市具有较强的预测能力 ;ASV模型的预测效果不理想 . 相似文献
80.
In this article we prove that the basic finite Hankel transform whose kernel is the third-type Jackson q-Bessel function has only infinitely many real and simple zeros, provided that q satisfies a condition additional to the standard one. We also study the asymptotic behavior of the zeros. The obtained results are applied to investigate the zeros of q-Bessel functions as well as the zeros of q-trigonometric functions. A basic analog of a theorem of G. Pólya (1918) on the zeros of sine and cosine transformations is also given. 相似文献