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Synthesis and Crystal Structure of Tri(4-(3-hydroxy2-ethyl-4-pyridinone-1-yl)-aniline Condensation Salicylaldehydato) Monohydratotricopper(II)Dimethylformamide Monohydrate Solvate

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Chinese Journal of Structural Chemistry 2003年第6期22卷 681-686页

作者： LUZai-Sheng NIUDe-Zhong TUShu-jiang CHENJiu-Tong DepartmentofUniversity XuzhouNormalUniversityXuzhouJiangsu221009China FujianInstituteofResearchontheStructureofMatter TheChineseAcademyofSciencesFuzhouFujian350002China

The title complex [Cu3L3(H2O)]DMFH2O (H2L = 4-(3-hydroxy-2-ethyl-4- pyridinone-1-yl)-aniline condensation salicylaldehyde) was obtained. The single-crystal X-ray study shows that it is a trinuclear compound [Cu3(C20H15N2O3)3(H2O)]DMFH2O. The coordi- nation sphere about each copper ion in the complex consists of two oxygen atoms from hydroxylpyridinone moiety of one ligand and one oxygen and one nitrogen atoms from salicyladehyde Schiff-base moiety of another ligand arranged in a slightly distorted square planar geometry. Among the three copper ions, one (Cu(2)) is coordinated by the other oxygen atom of water molecule on the fifth coordinate position to form a distorted square pyramid geometry. The crystal is of monoclinic, space group P21/c with a = 12.9202(5), b = 27.197(1), c = 17.0116(7) ? b = 100.588(1), V = 5875.9(4) 3, Z = 4, C63H57N7O12Cu3, Mr = 1294.78, Dc = 1.464 g/cm3, m = 1.146 mm-1, F(000) = 2668, R = 0.0784 and wR = 0.1546 for 6926 observed reflections with I > 2s(I). The differences of coordinate bond lengths are observed between anhydrous and hydrous units: in the former unit, the average bond lengths are 1.978 ?for CuN (azomethine), 1.883 ?for CuO (phenolic) in Schiff-base moiety, 1.959 ?for CuO (keto), and 1.919 ?for CuO (hydroxy) in hydroxypyridinone moiety; while those in the latter are longer with the following corresponding values: 1.985(5), 1.908(5), 1.993(5) and 1.919(4) ? respectively. The Cu(2)O (water) bond length is 2.375(6) ?

关键词： copper(II) complex 4-(3-hydroxy-2-ethyl-4-pyridinone-1-yl)-aniline salicylaldehyde Schiff-base crystal structure

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CFD simulation of internal-loop airlift reactor using EMMS drag model

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Particuology 2015年第2期13卷 124-132页

作者： Tingting Xu Xuedong jiang Ning Yang Jiahua Zhu State Key Laboratory of Multi-Phase Complex Systems Institute of Process EngineeringChinese Academy of Sciences University of Chinese Academy of Sciences Department of Chemical Engineering Xi'an Jiaotong University School of Chemical Engineering Sichuan University

The simulation of internal-loop airlift reactors is challenging because complex meso-scale structures exist in different sections of the reactor, separated by the draft tube. This paper reports on the computational fluid dynamics （CFD） simulation of internal-loop airlift reactors using a new drag model derived from the dual-bubble-size （DBS） model, an extended energy-minimization multi-scale （EMMS） approach for gas-liquid flows. Compared with the traditional Schiller-Naumann （S-N） correlation, the new model improves the simulation of gas holdup in the riser and downcomer significantly. In particular, gas holdup and circulation of two-phase flow can be modeled successfully using the new model, whereas traditional drag models such as the S-N correlation show an absence of gas in the downcomer. The simulation demonstrates the advantage and potential of this new model for internal-loop airlift reactors.

关键词： Computational fluid dynamics Internal-loop Airlift Multi-scale Multiphase flow Hydrodynamics

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一种多过程状态下新型船载式能量自循环系统研究

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机械传动 2015年第5期39卷 54-57页

作者：姜辉苏州经贸职业技术学院江苏苏州215009

针对船舶航行过程中能耗大、效率低等问题,设计一种新型船载式能量自循环系统,系统以船舶航行过程中周围流场运动作为动力源将流场动能转化为电能,模型中根据航行过程状态的不断变化引入DMC-PID混合预测控制算法对系统中带传动中的传动... 详细信息

针对船舶航行过程中能耗大、效率低等问题,设计一种新型船载式能量自循环系统,系统以船舶航行过程中周围流场运动作为动力源将流场动能转化为电能,模型中根据航行过程状态的不断变化引入DMC-PID混合预测控制算法对系统中带传动中的传动比进行调节,最后研究在传动比控制条件下带传动船载式能量自循环系统参数特征、性能指标的变化规律。分析结果表明,通过各项性能指标分析,设计的新型船载式能量自循环系统具有一定的可行性;能量自循环系统中引入可变传动比带传动系统和DMC-PID控制以后系统性能得到了一定的提高。

关键词：能量自循环船载式多过程状态

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On Designing Consistent Extended Kalman Filter

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Journal of Systems Science & Complexity 2017年第4期30卷 751-764页

作者： jiang Yanguang HUANG Yi XUE Wenchao FANG Haitao Beijing Institute of Control&Electronics Technology Beijing 100038China Key Laboratory of Systems and Control Academy of Mathematics and Systems Scienceand National Center for Mathematics and Interdisciplinary SciencesChinese Academy of SciencesBeijing 100190China

This paper studies the consistency of the extended Kalman filter(EKF) for a kind of nonlinear systems. Based on the EKF algorithm, the authors propose the quasi-consistent EKF(QCEKF)as well as the tuning law for its parameters. The quasi-consistency of the proposed algorithm is ***, the feasibility of the algorithm is illustrated by the numerical simulation on an orbit determination example.

关键词： Extended Kalman filter (EKF) consistency nonlinear system.

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A wall-thickness compensation strategy for wax pattern of hollow turbine blade

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Chinese Journal of Aeronautics 2019年第8期32卷 1982-1993页

作者： Kang CUI Wenhu WANG Ruisong jiang Dezhong ZHAO Key Laboratory of Contemporary Design and Integrated Manufacturing Technology Ministry of EducationNorthwestern Polytechnical University

As an important index affecting the aerodynamic performance and the structural strength of hollow turbine blades, the wall-thickness precision of the blade is mainly inherited from the positional relationship between the corresponding wax pattern and the internal ceramic ***, due to locating errors, the actual position of ceramic core is always deviated from the ideal position, which makes it difficult to guarantee the wall-thickness precision of the wax *** solve this problem, a wall-thickness compensation strategy is proposed in this paper. Firstly,based on the industrial computed tomography(ICT) technique and curve matching algorithms, a model reconstruction method is developed, with which the 3D model of a trial wax pattern can be easily constructed. After that, focusing on eliminating the wall-thickness errors of the trial wax pattern, an optimization method for the pose of the ceramic core in the wax pattern is proposed. Then, by mapping the optimal pose of the ceramic core to length adjustments of the locating rods, the wall-thickness errors of the wax pattern can be greatly reduced. A case study is also given to illustrate the effectiveness of the proposed compensation strategy.

关键词： Hollow turbine blade Locating compensation Model reconstruction Pose optimization Wax pattern Wall-thickness error

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A multi-rate sensor fusion approach using information filters for estimating aero-engine performance degradation

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Chinese Journal of Aeronautics 2019年第7期32卷 1603-1617页

作者： Feng LU Chunyu jiang Jinquan HUANG Xiaojie QIU jiangsu Province Key Laboratory of Aerospace Power System College of Energy and Power EngineeringNanjing University of Aeronautics and AstronauticsNanjing210016China Aviation Motor Control System Institute Aviation Industry Corporation of ChinaWuxi214063China

Gas-path performance estimation plays an important role in aero-engine health management, and Kalman Filter(KF) is a well-known technique to estimate performance degradation. In previous studies, it is assumed that different kinds of sensors are with the same sampling rate, and they are used for state estimation by the KF simultaneously. However, it is hard to achieve state estimation using various kinds of sensor measurements at the same sampling rate due to a complex network and physical characteristic differences between sensors, especially in an advanced multisensor architecture. For this purpose, a multi-rate sensor fusion using the information filtering approach is proposed based on the square-root cubature rule, which is called Multi-rate Squareroot Cubature Information Filter(MSCIF) to track engine performance degradation. Soft measurement synchronization of the MSCIF is designed to provide a sensor fusion condition for multiple sampling rates of measurement, and a fault sensor is isolated by maximum likelihood validation before state estimation. The contribution of this paper is to supply a novel multi-rate informationfilter approach for sensor fault tolerant health estimation of an aero-engine in a multi-sensor system. Tests are conducted for aero-engine performance degradation estimation with multiple sampling rates of sensor measurement on both digital simulation and semi-physical *** results illustrate the superiority of the proposed algorithm in terms of degradation estimation accuracy and robustness to sensor failure in a multi-sensor system.

关键词： Aero-engine Cubature information filter Performance degradation Sensor fusion State estimation

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STDNet: A Spatio-Temporal Decomposition Neural Network for Multivariate Time Series Forecasting

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Tsinghua Science and Technology 2024年第4期29卷 1232-1247页

作者： Zhuolun jiang zefei Ning Hao Miao Li Wang College of Computer Science and Technology(College of Data Science) Taiyuan University of TechnologyJinzhong 030600China

Long-term multivariate time series forecasting is an important task in engineering applications. It helps grasp the future development trend of data in real-time, which is of great significance for a wide variety of fields. Due to the non-linear and unstable characteristics of multivariate time series, the existing methods encounter difficulties in analyzing complex high-dimensional data and capturing latent relationships between multivariates in time series, thus affecting the performance of long-term prediction. In this paper, we propose a novel time series forecasting model based on multilayer perceptron that combines spatio-temporal decomposition and doubly residual stacking, namely Spatio-Temporal Decomposition Neural Network (STDNet). We decompose the originally complex and unstable time series into two parts, temporal term and spatial term. We design temporal module based on auto-correlation mechanism to discover temporal dependencies at the sub-series level, and spatial module based on convolutional neural network and self-attention mechanism to integrate multivariate information from two dimensions, global and local, respectively. Then we integrate the results obtained from the different modules to get the final forecast. Extensive experiments on four real-world datasets show that STDNet significantly outperforms other state-of-the-art methods, which provides an effective solution for long-term time series forecasting.

关键词： time series forecasting multivariate time series spatio-temporal decomposition

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Fault tolerant control for near space vehicle:a survey and some new results

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Journal of Systems Engineering and Electronics 2011年第1期22卷 88-94页

作者： Yufei Xu Bin jiang Zhifeng Gao Ke Zhang College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

A review on fault-tolerant control（FTC） for near space vehicle（NSV） is ***,the concept of near space is introduced,the background of NSV is emphasized,and the model characteristics of NSV in faulty case are ***,a comparison of different existing approaches is briefly carried out,and achievements on the current research in this field are also presented in the view of the practical ***,several existing advanced FTC results for nonlinear flight control systems are ***,the recent literature of NSV are presented to provide an overall view of future developments in this area.

关键词： near space vehicle(NSV) fault-tolerant control(FTC) adaptive sliding mode.

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Unraveling the amplified chiroptical responses of rylene-bladed quintuple[6]helicenes

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Science China Chemistry 2023年第8期66卷 2400-2407页

作者： Yanan Wu Yujian Liu Wei jiang Zhaohui Wang Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing100084China

Unraveling the key structural features to maximize the chiroptical properties is of significance for developing high-performance chiral *** we present our first attempt to elucidate and understand the molecular design of excellent chiroptical properties via the combination of multiplicity and the alignment of *** stereoisomeric PDI-bladed quintuple[6]helicenes,namely D_(5)-CRP and C_(2)-CRP,were revealed to show distinct spatial arrangements of *** dichroism(CD)spectra showed that the Cotton effects(Δε)are reaching 1,412 mol-1L cm-1for D_(5)-CRP and 669 mol^(-1)L cm^(-1)for C_(2)-CRP in the visible *** greatly amplifiedΔεrelative to the smaller analogue NPDH arises from the circular annulation of helicenes and high molecular symmetry that could significantly regulate the transition dipole moments and thereby make them tend to be(anti)parallel,as supported by TDDFT calculations for the rotatory strength(R).Consequently,the maximal dissymmetry factors(|g_(abs)|and|g_(lum)|)of this kind of chiral molecular carbon imides were estimated to be up to 0.021 and 0.012,*** study provides a deep insight into the chiroptical properties of complicated chiral systems.

关键词： chiral molecular carbon imides perylene diimides quintuple helicenes molecular symmetry chiroptical properties

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Dissociation characteristics of methane hydrate using depressurization combined with thermal stimulation

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Chinese Journal of Chemical Engineering 2019年第9期27卷 2089-2098页

作者： Mingjun Yang Zhanquan Ma Yi Gao Lanlan jiang Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education Dalian University of Technology

Methane hydrate is considered as a potential energy source in the future due to its abundant reserves and high energy *** investigate the influence of initial hydrate saturation,production pressure,and the temperature of thermal stimulation on gas production rate and cumulative gas production percentage,we conducted the methane hydrate dissociation experiments using depressurization,thermal stimulation and a combination of two methods in this *** is found that when the gas production pressures are the same,the higher the hydrate initial saturation,the greater change in hydrate reservoir ***,it is easier to appear the phenomenon of icing and hydrate reformation when the hydrate saturation is *** example,the reservoir temperature dropped to below zero in depressurization process when the hydrate saturation was about 37%.However,the same phenomenon didn’t appear as the saturation was about 12%.This may be due to more free gas in the reservoir with hydrate saturated of 37%.We also find that the temperature variation of reservoir can be reduced effectively by combination of depressurization and thermal stimulation *** the average gas production rate is highest with combined method in the *** the pressure of gas production is 2 MPa,compared with depressurization,the average of gas production can increase 54%when the combined method is *** efficiency of gas production is very low when thermal stimulation was used *** the temperature of thermal stimulation is 11℃,the average rate of gas production in the experiment of thermal stimulation is less than 1/3 of that in the experiment of the combined method.

关键词： Methane hydrate Depressurization Thermal stimulation Dissociation characteristics

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