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21.
土壤砷含量高光谱估算模型研究 总被引:2,自引:0,他引:2
以实验室内测取的土壤反射光谱为研究对象,利用PLSR方法建立反射光谱与土壤As含量之间的模型,通过交叉验证、估算检验建模精度,探讨利用反射光谱估算士壤As含量的可行性.通过比较不同光谱预处理方法、不同光谱分辨率和不同OM含量条件下建模、验证和估算结果.表明,MSC方法可以有效去除散射的影响而取得较好的结果(估算R2=0... 相似文献
22.
Effects of reagent's rotational and vibrational excitations on reaction O(3P) + H2 H2(ν = 0, 3, j = 0, 3; 5; 7; 9; 12; 15) → OH + H 下载免费PDF全文
To investigate the effect of reagent's rotational and vibrational excitations on the stereo-dynamics of reaction product, the title reaction is theoretically simulated using the quasi-classical trajectory (QCT) method on the 3A" and 3A′ potential energy surfaces (PESs). The reaction cross section is considered as the only scalar property in this work at four different collision energies. Furthermore the vector properties including two polarization-dependent differential cross sections (PDDCSs), the angular distributions of product' rotational momentum are discussed at one fixed collision energy. Effects of reagents' rotational excitation on the reaction do exist regularly. 相似文献
23.
We propose a physical scheme for generating a two-atom cluster state through the simultaneous interaction of two two-level atoms with a single-mode cavity field prepared initially in an odd-coherent state under a large-detuned limit. The influence of the dissipation constant, the intensity of the field and the imperfect manipulation on the preparation scheme are investigated. It is shown that when the intensity of the cavity is large enough, the influence of the cavity decay is ettlciently suppressed. The possible error in the implementation of the cluster state is negligible when the time difference between two atoms crossing the cavity axis is small. It is suggested that the scheme can be realized by current technologies. 相似文献
24.
Shao-Hua Xiang Zhen-Gang Shi Wei Wen De-Hua Lu Xi-Xiang Zhu Ke-Hui Song 《Optics Communications》2011,284(9):2402-2407
We propose a protocol to concentrate partially entangled states of photons using entanglement reflector, which consists of a single electron spin confined in a charged quantum dot inside a single-sided microcavity. The outstanding advantage of the proposed scheme is its experimental simplicity and feasibility since it only needs to perform a single local measurement on electronic spins rather than a joint Bell-state measurement on photons. We then extend this scheme to concentrate N-photon Greenberger-Horne-Zeilinger state. Finally, we analyze the influence of various imperfections on the scheme. 相似文献
25.
We study the entanglement dynamics between two strongly-AC-driven superconducting charge qubits coupled collectively to a zero temperature, dissipative resonator and find an unusual feather that the competing of creation and annihilation of entanglement can lead to entanglement increasing, sudden death and revival. We also calculate the dependence of the death time on the initial state of the system. 相似文献
26.
A dinuclear cobalt(Ⅱ) complex [Co2(α-furacrylato)4(Phen)2(H2O)]·C2H5OH has been synthesized with α-furacrylic acid and 1,10-phenanthroline as the ligands, and its crystal structure was determined. The crystal is of monoclinic system, space group C2/c with a=1.07388(8), b=2.4300(2), c=1.86708(14)nm, β=104.3830(10)o, V=4.719.4(7) nm3 , Dc=1.503 g/cm3 , Z=2, F(000)=2196, GOOF=1.053, the final R=0.0343 and wR=0.0883. The crystal structure shows that two neighboring cobalt(Ⅱ) ions are linked by the bridging coordination of two α-furacrylic acid anions and one water molecule, and their end positions are respectively coordinated with two 1,10-phenanthroline molecules and two α-furacrylic acid anions, forming a dinuclear structure. Both cobalt(Ⅱ) ions adopt hexa-coordinated distorted octahedral geometry. The electrochemical and fluorescence properties of the title complex are also discussed. 相似文献
27.
28.
Nonlinear Dynamics - In this paper, a (2+1)-dimensional Caudrey–Dodd–Gibbon–Kotera–Sawada system is investigated in fluid mechanics via the symbolic computation. With the... 相似文献
29.
Xin Lin Xi-Long Yu Fei Li Shao-Hua Zhang Jian-Guo Xin Xin-Yu Zhang 《Acta Mechanica Sinica》2012,28(5):1296-1302
Non-equilibrium radiation measurements behind strong shock wave for simulated Martian atmosphere are presented in this paper. The shock wave is established in a hydrogen oxygen combustion driven shock tube. Timeresolved spectra of the Δv = 0 sequence of the B 2Σ+ → X 2Σ+ electronic transition of CN have been observed through optical emission spectroscopy (OES). A new method, which is based on fitting high resolution spectrum for rotational and vibrational temperatures measurement, is proposed to diagnose temperature distribution behind the shock wave. It is estimated that the current scheme has the maximum deviation less than 8% (1σ) for vibrational temperature measurement through detailed analysis of the influence of the uncertainties of spectroscopic constants and spectral resolution. Radiation structure of the shock layer, including induction, relaxation and equilibrium process, and corresponding rotational and vibrational temperatures are obtained through time gating OES diagnostics with sub-microsecond temporal resolution. The present extensive results will strongly benefit the reaction rate estimation and computational fluid dynamics (CFD) code validation in high enthalpy Mars reentry chemistry. 相似文献
30.
Jin-Fang Nie Hai-Long Wu A-Lin Xia Shao-Hua Zhu Ying-Chao Bian Shu-Fang Li Ru-Qin Yu 《Analytical sciences》2007,23(12):1377-1382
This paper proposes a new and effective approach for the quantitative analysis of sulpiride, a significant antipsychotic drug, in human urine samples by the incorporation of excitation-emission matrix (EEM) fluorescence and second-order calibration methodologies based on the alternating fitting residue (AFR) and self-weighted alternating trilinear decomposition (SWATLD) algorithms. With the application of a second-order advantage, the proposed strategy could be utilized for a direct concentration determination of sulpiride with a simple pretreatment step, even in the presence of serious natural fluorescent interferences. The average recoveries of sulpiride in complex urine samples by using AFR and SWATLD with an estimated component number of three were 101.2 +/- 2.1 and 94.4 +/- 0.7%, respectively. Moreover, the accuracy of the two algorithms was also evaluated through elliptical joint confidence region (EJCR) tests as well as the figures of merit, such as sensitivity (SEN), selectivity (SEL) and limit of detection (LOD). The experimental results demonstrated that both algorithms, as promising quantitative alternatives, have been satisfactorily applied to the determination of sulpiride in human urine, but the performance of AFR was slightly better than that of SWATLD. 相似文献