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21.
The enhancement of teleportation fidelity by weak measurement or quantum measurement reversal is investigated. One qubit of a maximally entangled state undergoes the amplitude damping, and the subsequent application of weak measurement or quantum measurement reversal could improve the teleportation fidelity beyond the classical region. The improvement could not be attributed to the increasing of entanglement, quantum discord, classical correlation or total correlation. We declare that it should be owed to the probabilistic nature of the method. 相似文献
22.
In magneto-Archimedes levitation, a polymer can be levitated to a balanced position, and its levitation height is mainly related to the density of the polymer. Here, a novel method for measuring the density of polymers based on magneto- Archimedes levitation is proposed. For a designed measurement device, an equation can be fitted by a series of experiments with standard density glass beads. Then, the polymer's density can be calculated via the equation. In this paper, a device with magnets at a distance of 60 mm was chosen as an example. Experimental results showed that the proposed method could measure all types of polymer with an accuracy of 0.002–0.01 g/cm3. Moreover, the proposed method can clearly distinguish between polymers with small density differences (<0.03 g/cm3). Because of its high accuracy, high sensitivity, low cost and convenience, the proposed method could be widely used in polymer testing, especially in density-based testing. 相似文献
23.
Christian Schlereth Christine Eckert René Schaaf Bernd Skiera 《European Journal of Operational Research》2014
Self-explicated approaches are popular preference measurement approaches for products with many attributes. This article classifies previous self-explicated approaches according to their evaluation types, i.e. trade-off- versus non-trade-off-based, and outlines their advantages and disadvantages. In addition, it proposes a new method, the presorted adaptive self-explicated approach that is based on Netzer and Srinivasan’s (2011) adaptive self-explicated approach and that combines trade-off- and non-trade-off-based evaluation types. Two empirical studies compare this new method with the most popular existing self-explicated approaches, including the adaptive self-explicated approach and paired comparison preference measurement. The new method overcomes the insufficient discrimination between importance weights, as usually found in non-trade-off-based evaluation types; discourages respondents’ simplification strategies, as are frequently encountered in trade-off evaluation types; is easy to implement; and yields high predictive validity compared with other popular self-explicated approaches. 相似文献
24.
Reflections from geometric discontinuities can be used with ultrasonic energy to predict the temperature of an interface where classical temperature measurement techniques are impractical because of physical access limitations or harsh environmental conditions. Additionally, these same ultrasonic measurements can be used with inversion methods commonly applied to ill-posed heat transfer problems to increase the accuracy of the measurement of surface temperature or heat flux at the surface of interest. Both methods for determining surface temperature are presented, along with a comparison of results both from a verification example and using data gathered in a field test of the methods. The results obtained with these two methods are shown to be in good agreement with an empirical relationship used in the design of large caliber guns. 相似文献
25.
针对钨矿石中的微量元素磷,采用混合酸快速微波消解结合磷钼蓝分光光度法进行测定。经选择优化样品的微波消解和实验测定条件,结果表明:HCl+HNO3+HF的混合酸微波消解后的样品,在硫酸介质中,有钼酸铵存在时,用抗坏血酸将磷还原成磷钼蓝络合物,在825nm处比色测定。方法的加标回收率为98.9%~101.6%,结果准确可靠。硅在熔样过程中挥发除去不会干扰测定,砷会干扰实验,可在酸介质中加入碘化钾,使砷还原至低价而不干扰磷的测定。 相似文献
26.
金生 《中国无机分析化学》2015,5(4)
本文的主要实验目的是利用DMA-80测汞仪直接测定固体样品中的汞并证明其方法可靠。采用升温加热直接进行热分解、金汞齐反应,采用长、短双检测池,可直接测定固体、液体样品,汞含量在0.n×10-9~600.0×10-9范围内的样品都能被很准确地测定,每个样品测定时间约为5min。 测试结果证明其方法具可靠性。 相似文献
27.
在基于相位分析的三维测量系统中,为了准确地得到物体的高度,相位展开扮演着很重要的角色。传统的相位展开方法常常需要额外的投影图,而傅里叶变换轮廓术只需要采集一幅或两幅变形条纹图就可以实现对物体轮廓的测量,其方法速度快,易于实现。针对傅里叶变换轮廓术方法计算得到的截断相位分布,本文提出了一种利用截断相位与参考平面相位差值2π的整数倍数获得截断相位的正确级次,辅助相位展开的方法。当被测物体较复杂,或者相位截断次数较多时,该方法在已有参考平面相位的基础上虚拟新的相位平面,依次比较截断相位和虚拟相位,进行多次分级相位展开,结合多个展开相位结果,最终得到正确的展开相位。该方法展开速度快,展开错误不会蔓延传递。仿真和实物实验结果证明了该方法的可行性,说明该方法可用于傅里叶变换轮廓术中进行截断相位的快速展开。 相似文献
28.
We extend the instrumental variable method for the mean regression models to linear quantile regression models with errors-in-variables. The proposed estimator is consistent and asymptotically normally distributed under some fairly general conditions. Moreover, this approach is practical and easy to implement. Simulation studies show that the finite sample performance of the estimator is satisfactory. The method is applied to a real data study of education and wages. 相似文献
29.
Luyi Chen Ping Xiao Bin Hu Yiwen Wang Jianmao Yang Jianyun Liu 《Electroanalysis》2023,35(5):e202200521
3-dimensional (3D) Fe−Co−LDH/MXene composite was synthesized by in-situ synthesis and assembly of Fe−Co−LDH rod around MXene under hydrothermal condition. Due to the unique 3D configuration and good conductivity, the obtained Fe−Co−LDH/MXene modified glassy carbon electrode (Fe−Co−LDH/MXene/GCE) showed excellent electrochemical activity for As(III) detection. Via square-wave anodic stripping voltammetry, the response current on Fe−Co−LDH/MXene/GCE had good linear relationship with As(III) concentrations (1∼1000 ppt) with superior sensitivity (0.22 μA ppt−1 cm−2) and low detection limit (0.9 ppt). The mechanism of As(III) adsorption was demonstrated. The electrode showed excellent anti-interference ability. Real water sample analysis demonstrated the Fe−Co−LDH/MXene/GCE was deployable in aqua-system. 相似文献
30.
《Arabian Journal of Chemistry》2023,16(2):104515
In this work, the development of the eco-friendly comprehensive scale and corrosion inhibitor based on green polyaspartic acid (PASP) was presented. In this view, PASPG was prepared by a ring-opening graft modification reaction of polysuccinimide (PSI) with glycidyl. In addition, the molecular structure and the thermal stability of PASPG were characterized by using three different methods (FTIR, 1H NMR, and TGA). PASPG’s scale inhibition efficiency and corrosion inhibition efficiency were also evaluated, respectively. More concretely, the scale inhibition efficiency of PASPG achieved 94.6 % and 95.1 % for CaCO3 and CaSO4, respectively. With the aid of the FTIR and SEM measurement techniques, it was found that PASPG could induce the irregular growth of the CaCO3 and CaSO4 morphology and destroy the formation of crystals. On the other hand, the higher corrosion efficiency of 85.17 % was achieved by PASPG in comparison with PASP (72.53 %). PASPG is a mixed inhibitor and the adsorption of PASPG on the Q235 steel surface followed the Langmuir mono-layer adsorption isotherm. The formation of a protective film on the surface of carbon steel was proved by PASPG’s adsorption, which increased the resistance to be eroded. Thus, the surface of carbon steel can be effectively protected. The present work provides a simple and effective pathway for the synthesis of high-efficiency green scale and corrosion inhibitor, by introducing a functional group into the PASP chains. The implementation of such type of chemical modification method may also be an effective strategy for improving the efficiency of other polymers green scale and corrosion inhibitors. 相似文献