超细氮化硅粉的组成分析和评估

采用X荧光光谱、等离子发射光谱、原子吸收光度、气相色谱以及重量法、容量法等多种分析技术对超细氮化硅粉中硅、氮、氧、氯根、水分及金属杂质等组成进行了分析方法研究。确定了测值可信且再现性好的分析方法。通过程序升温、红外检测及微机解卷重叠峰形,探讨了氮化硅中不同状态的氧量,进而对主相量作出评估。国内用高频等离子法和激光诱导合成的氮化硅超细粉,主相量均达97％以上,其组成式接近为Si_(30)N_(10)O。

超细碳氮化钛的分析和评估

采用多种技术对超细碳氮化钛进行组成分析。可分别测定吸附和化合状态的氧。晶格常数与(原子比)具有线性关系,表明碳与氮可以相互无限置换,分子式为Ti C_xN_(1-x),每一样品只有一种C/N比.固溶体是均质的。气相合成的碳氮化钛含微量杂质,包括游离碳和氯根等,主相量显著地受吸附氧量影响,可控制达97％以上。介绍了拟定的分析方法。

Identification of Similar Air Traffic Scenes with Active Metric Learning

The rapid growth of air traffic has continuously increased the workload of controllers,which has become an important factor restricting sector capacity.If similar traffic scenes can be identified,the historical decision-making experience may be used to help controllers decide control strategies quickly.Considering that there are many traffic scenes and it is hard to label them all,in this paper,we propose an active SVM metric learning(ASVM2L)algorithm to measure and identify the similar traffic scenes.First of all,we obtain some traffic scene samples correctly labeled by experienced air traffic controllers.We design an active sampling strategy based on voting difference to choose the most valuable unlabeled samples and label them.Then the metric matrix of all the labeled samples is learned and used to complete the classification of traffic scenes.We verify the effectiveness of ASVM2L on standard data sets,and then use it to measure and classify the traffic scenes on the historical air traffic data set of the Central South Sector of China.The experimental results show that,compared with other existing methods,the proposed method can use the information of traffic scene samples more thoroughly and achieve better classification performance under limited labeled samples.

Decoherence of a Double Quantum Dot Charge Qubit Approached with Redfield Equation

In this paper, we investigate the decoherence time of a double quantum dot （DQD） charge qubit in three kinds of baths through solving dynamics of the qubit. The dynamics of the qubit is investigated with Redfield master equation. It is shown that the decoherence time of the qubit in Ohmic bath has the same order of magnitude as the experiments reported. When the environment is modeled with the supra-Ohmic bath the decoherence time of the qubit is shorter than the experimental result. And when modeled with the sub-Ohmic bath the decoherence time of the qubit is longer than the experimental result.

Modeling and monitoring of nonlinear multi-mode processes based on similarity measure-KPCA

A new modeling and monitoring approach for multi-mode processes is proposed.The method of similarity measure(SM) and kernel principal component analysis(KPCA) are integrated to construct SM-KPCA monitoring scheme,where SM method serves as the separation of common subspace and specific subspace.Compared with the traditional methods,the main contributions of this work are:1) SM consisted of two measures of distance and angle to accommodate process characters.The different monitoring effect involves putting on the different weight,which would simplify the monitoring model structure and enhance its reliability and robustness.2) The proposed method can be used to find faults by the common space and judge which mode the fault belongs to by the specific subspace.Results of algorithm analysis and fault detection experiments indicate the validity and practicability of the presented method.

Brun-Type Formalism for Decoherence in Two-Dimensional Quantum Walks

We study decoherence in the quantum walk on the xy-plane. We generalize the method of decoherent coin quantum walk, introduced by [T.A. Brun, et al., Phys. Rev. A 67 （2003） 032304], which could be applicable to all sorts of decoherence in two-dimensional quantum walks, irrespective of the unitary transformation governing the walk. As an application we study decoherence in the presence of broken line noise in which the quantum walk is governed by the two-dimensional ttadamard operator.

Perturbation Theory for Open Two-Level Nonlinear Quantum Systems

Perturbation theory is an important tool in quantum mechanics. In this paper, we extend the traditional perturbation theory to open nonlinear two-level systems, treating decoherence parameter γ as a perturbation. By this virtue, we give a perturbative solution to the master equation, which describes a nonlinear open quantum system. The results show that for small decoherence rate γ the ratio of the nonlinear rate C to the tunneling coefficient V （i.e., r = O/V） determines the validity of the perturbation theory. For small ratio r, the perturbation theory is valid, otherwise it yields wrong results.

Influences of Metals and Acids on the Photo Reduction of CO2 under Catalysis of TiO2

Conversion of green house CO2 into fuel gas in the presence of reducing agent sources that are Fe and Zn powder, as well as hydrogen ions supplier such as nitric and acetic acids by photo catalytic reduction with water vapor on TiO2 has been studied. The photo reduction was carried out by batch technique, using a UV lamp with a wave length of 290-400 nm, as a photon source. The gasses produced from the photo reduction were determined by gas chromatography. The research results indicate that the photo reduction of CO2 has successfully produced methane as a dominant product. The presence of the metals in addition to be able to improve the methane yield, it is also able to induce ethylene formation. Meanwhile the acids can considerably enhance the methane yield without formation of ethylene. Furthermore, the enhancement is observed to be controlled by mass of the metals, and the acid concentrations. It is also found that Zn and HNO3 show stronger effect in the increasing CO2 photo reduction.

Study on GC-MS fingerprint of petroleum ether fraction of Shenqi Jiangtang Granules

Objective To establish gas chromatography-mass spectrometry(GC-MS)fingerprint method for the petroleum ether fraction of Shenqi Jiangtang Granules(SQJTG)and evaluate the product quality.Methods The GC-MS fingerprint of petroleum ether fraction of SQJTG was established by GC-MS,and the chemical components corresponding to the fingerprint peaks were structurally identified on NIST2014.The batch consistency of SQJTG products was evaluated based on the chemical composition of petroleum ether parts by using fingerprint similarity evaluation and Principal components analysis(PCA)technology.At the same time,Hotelling's T2 and DMODX statistics are used to set the control range for the quality of different batches of products.Results Twenty-two components were identified from the petroleum ether part of SQJTG,accounting for 60.94%of the total components separated.The similarity of fingerprints of petroleum ether parts of 24 batches of SQJTG was greater than 0.95.The PCA of 24 batches of samples were all under the control limits of Hotellin’s T2 and DMODX statistics,indicating that the petroleum ether parts of different batches of SQJTG were consistent.Conclusion The developed GC-MS fingerprint method can be used to evaluate the quality of SQJTG.