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Anion structural effects on interaction of rare earth element ions with Dowex 50W X8 cation exchange resin

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Journal of Rare Earths 2018年第8期36卷 879-890页

作者： Duane D.Miller Ranjani Siriwardane Dustin Mcintyre U.S. Department of Energy National Energy Technology Laboratory aecom

The effect of the anion in the original rare earth element（REE） solution on the reversible ion exchange of Ce nitrate and Ce sulfate with the Dowex 50 W X8 was investigated using attenuated total reflection infrared（ATR-IR） spectroscopy, continuous flow reactor studies coupled with inductively coupled plasma mass spectroscopy（ICP-MS）, and density functional theory（DFT）. The simulated IR spectrum at the DFT B3 LYP/6-31 G（d） level was compared to the experimental results to characterize the IR spectrum, molecular interactions, and bonding of the ion exchanged species. The continuous liquid flow reactor studies show a capacity of 0.72 mmol/g sorbent for the Ce nitrateand 0.96 mmol/g sorbent for the Ce sulfate with the Dowex 50 W X8. The flow reactor studies reveal the type of solute anion（SO_4^（（2-）） or NO_3^（（-））） associated with the REE during cation exchange significantly affects the sorption capacity of the Dowex 50 W X8 ion exchange resin. The calculated REE binding energy（BE） and the DFT optimized structures suggest that the differences in sorption capacity is the result of the formation of different types of partially ionexchanged Ce_2^（（3＋））2 SO_4^（（2-）） and Ce^（（3＋）） 3 NO_3^（（-））. These results suggest that the solute anion affects the equilibrium constants of the Dowex resin by the formation of a charged layer capable of retaining the counterion. Modifying the sulfonic acid site（H＋） in the Dowex 50 W X8 with the NH_4~＋ counterion does not affect the sorption capacity and retention times of the Ce nitrate and Ce sulfate species. These results suggest that the counterions and co-ions having a finite size, may limit access to the Dowex sulfonate active site where the type of REE cation as a nitrate or sulfate in solution may significantly modify the sorption capacity of the ion exchange resin. Similar results are obtained during sorption with nitrates and sulfates of Sm and Yb.

关键词： Ion exchange Dowex Anion effects Rare earth metal sorption

SOI-based radial-contour-mode micromechanical disk resonator

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Journal of Semiconductors 2011年第11期32卷 72-76页

作者：贾英茜赵正平杨拥军胡晓东李倩 School of Information Engineering Hebei University of Technology The 13th Research Institute China Electronics Technology Group Corporation China Electronics technology Group corporation

This paper reports a radial-contour-mode micromechanical disk resonator for radio frequency applications. This disk resonator with a gold plated layer as the electrodes, was prepared on a silicon-on-insulator wafer, which is supported by an anchor on another silicon wafer through Au-Au thermo-compression bonding. The gap between the disk and the surrounding gold electrodes is 100 nm. The radius of the disk is 20μm and the thickness is 4.5 μm. In results, the resonator shows a resonant frequency of 143 MHz and a quality factor of 5600 in vacuum

关键词： RF-MEMS micromechanical disk resonator SOI, thermo-compression bonding

The future of carbon-neutrality science and technology from an industrial transformation perspective:an interview with Hou-Liang Dai

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National Science Review 2023年第9期10卷 113-115页

作者： Hai-Xia Huang the Science and technology Department of the China National Petroleum corporation

Since China announced that it will strive to achieve its carbon peak by 2030 and carbon neutrality by 2060, it has determined to take steps, which will establish low carbon development and a transition to carbon neutrality,as part of its long-term strategyfor sustainable development and *** will be both a huge challenge and an *** achieve the dual-carbon goals,the whole society must undergo a broad and profound systemic transformation, involving changes in energy,technology,economy, industry and lifestyle, ***-neutrality science and technology should be the foundation of the transformation.

关键词： Carbon

Indirect Radau pseudospectral method for the receding horizon control problem

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Chinese Journal of Aeronautics 2016年第1期29卷 215-227页

作者： Liao Yuxin Li Huifeng Bao Weimin School of Astronautics Beihang University Science and technology Committee China Aerospace Science and Technology Corporation

To solve the receding horizon control （RHC） problem in an online manner, a novel numerical method called the indirect Radau pseudospectral method （IRPM） is proposed in this paper. Based on calculus of variations and the first-order necessary optimality condition, the RHC problem for linear time-varying （LTV） system is transformed into the two-point boundary value problem （TPBVP）. The Radau pseudospectral approximation is employed to discretize the TPBVP into well-posed linear algebraic equations. The resulting linear algebraic equations are solved via a matrix partitioning approach afterwards to obtain the optimal feedback control law. For the nonlinear system, the linearization method or the quasi linearization method is employed to approximate the RHC problem with successive linear approximations. Subsequently, each linear problem is solved via the similar method which is used to solve the RHC problem for LTV system. Simulation results of three examples show that the IRPM is of high accuracy and of high compu- tation efficiency to solve the RHC problem and the stability of closed-loop systems is guaranteed.

关键词： Indirect Radau pseudospec-tral method Linear time-varying system Nonlinear system Receding horizon control Two-point boundary valueproblem

M-FCN based sea-surface weak target detection

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Journal of Systems Engineering and Electronics 2021年第5期32卷 1111-1118页

作者： PAN Meiyan SUN Jun YANG Yuhao LI Dasheng YU Junpeng The 14th Research Institute of China Electronics technology Group corporation Nanjing 210039China Key Laboratory of IntelliSense technology China Electronics Technology Group CorporationNanjing 210039China

This paper focuses on the sea-surface weak target detection based on memory-fully convolutional network(M-FCN)in strong sea ***,the constant false alarm rate(CFAR)detection method utilizes a low threshold with high probability of false alarm to detect sea-surface weak targets after non-coherent *** the detection threshold can generate a large number of false alarms while increasing the detection rate,and how to suppress a large number of false alarms is the key to improve the performance of weak target ***,the detection result of the low threshold is operated to construct the target matrix suitable for the size of fully convolutional networks and the convolution operator ***,the M-FCN architecture is designed to learn the different accumulation characteristics of the target and the sea clutter between different *** improving the detection performance,the historical multi-frame information is memorized by the network,and the end-to-end structure is established to detect sea-surface weak target *** results on measured data demonstrate that the M-FCN method outperforms the traditional track before detection(TBD)method and reduces false alarm tracks by 35.1%,which greatly improves the track quality.

关键词： sea-surface weak target detection memory-fully convolutional network(M-FCN) multi-frame information end-to-end

Solid-Phase Decarburization of High-Carbon Ferromanganese Powders by Microwave Heating

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Journal of Iron and Steel Research International 2013年第8期20卷 34-40页

作者： GUO Li-na CHEN Jin SHI Wen-li ZHAO Jing LIU Ke LIU Jin-ying College of Materials Science and Engineering Taiyuan University of Technology Lian-zhi technology corporation of Xiangtan City No.12 Research Institute China Electronics Technology Group Corporation

The solid-phase decarburization of high-carbon ferromanganese powders （HCFPs） was investigated using calcium carbonate as the decarburizer by microwave heating and conventional heating methods to explore the differ-ences of microwave heating and conventional heating. Experimental results show that HCFPs containing ***-bonate were heated up to 900, 1000, 1 100, and 1200 ℃ and held for 60 rain for decarburization by microwave heat-ing at decarburization ratios of 76.69%, 82.90%, 84.11%, and 85. 75%, respectively. These ratios are higher than the decarburization ratios used for conventional heating under the same experimental conditipns. The microwave heat- ing can significantly improve decarburization ratio. This indicates the microwave heating field features a non-thermal effect, which in turn, visibly enhances the carbon diffusion ability of HCFPs. It also improves the kinetic conditions of solid-phase decarburization.

关键词： high-carbon ferromanganese powder solid-phase decarburization microwave heating conventional heating

Analysis and Field Trial Results on C-Plane and U-Plane Split Scheme in Virtual Sectorization System

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China Communications 2015年第11期12卷 53-61页

作者： XIE Weiliang WU Zhouyun YANG Fengyi YANG Tao technology Innovation Center China Telecom Corporation Limited

Capacity enhancement approaches are being intensively studied in the past few years to address the soaring capacity demands. The network densif ication technology is recognized as one promising solution. However,the ultra-dense network scheme suffers from severe interference and frequent handovers,which degrade the system performance significantly. In this paper,a virtual sectorization system leveraging a C-plane(control signaling plane) and U-plane(user data plane) split scheme is proposed to overcome these two fundamental problems. Besides,a well-designed fi eld trial is conducted to evaluate its performance. The results show that the interference can be avoided,which leads to a tremendous increase in system capacity. In addition,the number of handovers is also greatly decreased. Thus,the trial results verify the huge potential of the C-plane and U-plane split scheme for system capacity and user experience enhancements.

关键词： C-plane/U-plane split virtual sectorization handover interference

A Flexible Three Clouds 5G Mobile Network Architecture Based on NFV & SDN

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China Communications 2015年第S1期12卷 121-131页

作者： YANG Fengyi WANG Haining MEI Chengli ZHANG Jianmin WANG Min China Telecom corporation Limited technology Innovation Center

Along with the completion of the development of 4G technologies, the global mobile community starts the study of the next generation technologies, i.e. 5G technologies. This paper proposes a new flexible architecture for 5G mobile networks based on Network Function Virtualization(NFV) and Software Defined Network(SDN) technologies, which is adaptable to use cases and scenarios. Then implementation reference architecture and some typical 5G network deployment cases are discussed. Besides, some key issues for further study are also indicated at the end.

关键词： 5G network architecture NFV SDN deployment

Consistency check of degradation mechanism between natural storage and enhancement test for missile servo system

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Journal of Systems Engineering and Electronics 2019年第2期30卷 415-424页

作者： Wang Xu Sun Quan College of Information Systems and Management National University of Defense Technology The Second Academy of China Aerospace Science and Industry corporation Hunan Ginkgo Reliability technology Institute Limited corporation

Reliability enhancement testing(RET) is an accelerated testing which hastens the performance degradation process to surface its inherent defects of design and manufacture. It is an important hypothesis that the degradation mechanism of the RET is the same as the one of the normal stress condition. In order to check the consistency of two mechanisms, we conduct two enhancement tests with a missile servo system as an object of the study, and preprocess two sets of test data to establish the accelerated degradation models regarding the temperature change rate that is assumed to be the main applied stress of the servo system during the natural storage. Based on the accelerated degradation models and natural storage profile of the servo system, we provide and demonstrate a procedure to check the consistency of two mechanisms by checking the correlation and difference of two sets of degradation data. The results indicate that the two degradation mechanisms are significantly consistent with each other.

关键词： reliability enhancement testing (RET) degradation model accelerated equation consistency check Pearson correlation coefficient