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用于沼气纯化的有机胺溶液吸收法研究进展

中国环境科学 2024年第2期44卷 894-902页

作者：孟凡志韩思宇林莉李婧琳陈凯轮蒋建国清华大学环境学院北京100084

有机胺溶液吸收法作为一项成熟的碳捕集技术,具有CO_(2)吸收速率快、选择性高及再生效果好等诸多优点,在沼气纯化领域具有重要的研究意义和应用价值,但也存在再生能耗高、易于挥发、易于降解和一些环境风险问题.不同类型的胺所表现出的... 详细信息

有机胺溶液吸收法作为一项成熟的碳捕集技术,具有CO_(2)吸收速率快、选择性高及再生效果好等诸多优点,在沼气纯化领域具有重要的研究意义和应用价值,但也存在再生能耗高、易于挥发、易于降解和一些环境风险问题.不同类型的胺所表现出的沼气纯化效果不同,其中伯胺和仲胺的CO_(2)吸收速率较快,但再生所需的能耗较大,叔胺和空间位阻胺的CO_(2)吸收速率较慢,但再生能耗较低.本文从有机胺吸收法的工艺流程、反应机理、可操控变量、存在的问题及其应用现状等方面系统地回顾了有机胺吸收法在沼气纯化领域的研究进展,提出了相应的研究思路和建议,为继续推动有机胺吸收法在沼气纯化领域的应用提供指导.研究结果表明,适当提升有机胺的浓度可以明显提高CO_(2)的吸收效率,且混合胺溶液有利于改善单胺溶液沼气纯化过程中经济性较低的问题.此外,相比于传统的干法吸收法,有机胺溶液吸收法在CO_(2)捕集过程中的能耗会增加30%以上,这意味着有机胺溶液吸收法相对于干法吸收法需要更多的能源投入.

关键词：有机胺碳捕集沼气纯化反应机理再生能耗

Investigation of basic properties of fly ash from urban waste incinerators in China

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Journal of Environmental Sciences 2007年第4期19卷 458-463页

作者： jiang jian-guo XU Xin WANG Jun YANG Shi-jian ZHANG Yan Department of Environmental Science and Engineering Tsinghua University Beifing 100084 China. Shanghai Environment and Science Academy Shanghai 201203 China

Basic properties of fly ash samples from different urban waste combustion facilities in China were analyzed using as X-ray fluorescence （XRF）, scanning electron microscopy （SEM）, X-ray diffraction （XRD）. The leaching toxicity procedure and some factors influencing heavy metals distribution in fly ash were further investigated. Experimental results indicate that the fly ash structures are complex and its properties are variable. The results of XRF and SEM revealed that the major elements （〉10000 mg/kg, listed in decreasing order of abundance） in fly ash are O, Ca, Cl, Si, S, K, Na, Al, Fe and Zn. These elements account for 93% to 97%, and the content of Cl ranges from 6.93% to 29.18 %, while that of SiO2 does from 4.48% to 24.84%. The minor elements （1000 to 10000 mg/kg） include Cr, Cu and Pb. Primary heavy metals in fly ash include Zn, Pb, Cr, Cu etc. According to standard leaching test, heavy metal leaching levels vary from 0 to 163.10 mg/L （Pb） and from 0.049 to 164.90 mg/L （Zn）, mostly exceeding the Chinese Identification Standard for hazardous wastes. Morphology of fly ash is irregular, with both amorphous structures and polycrystalline aggregates. Further research showed that heavy metals were volatilized at a high furnace temperature, condensed when cooling down during the post-furnace system and captured at air pollution control systems. Generally, heavy metals are mainly present in the forms of aerosol particulates or tiny particulates enriched on surfaces of fly ash particles. The properties of fly ash are greatly influenced by the treatment capacities of incinerators or the variation of waste retention time in chamber. Fly ash from combustors of larger capacities generally has higher contents of volatile component and higher leaching toxicity, while those of smaller capacities often produce fly ash containing higher levels of nonvolatile components and has lower toxicity. The content of heavy metals and leaching toxicity maybe have no convincing correlatio

关键词： urban waste incinerator fly ash heavy metals leaching toxicity

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基于GNSGA-Ⅱ算法的线圈优化设计

化工自动化及仪表 2024年第1期51卷 77-85页

作者：姜建国佟麟阁喻明斐东北石油大学电气信息工程学院

在电动汽车无线充电技术中,充电线圈的性能直接影响系统的整体传输性能。在分析常用线圈形状的基础上,引入拉梅曲线方程,设计了一种新型超圆角方形线圈;对耦合电路进行理论分析,得到优化目标传输效率和功率密度与待优化参数之间的关系;... 详细信息

在电动汽车无线充电技术中,充电线圈的性能直接影响系统的整体传输性能。在分析常用线圈形状的基础上,引入拉梅曲线方程,设计了一种新型超圆角方形线圈;对耦合电路进行理论分析,得到优化目标传输效率和功率密度与待优化参数之间的关系;利用改进的多目标优化算法(GNSGA-Ⅱ)进行线圈的参数优化,得到一组最优的参数解用于工程设计。该方法相比于传统有限元仿真计算法,具有节省时间的优点,优化设计结果表明该方法具有有效性。

关键词：多目标优化设计 GNSGA-Ⅱ算法无线充电超圆角方形线圈参数优化拉梅曲线方程

基于VisuShrink小波阈值变换的甲烷检测降噪技术

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化工自动化及仪表 2024年第3期51卷 410-416页

作者：姜建国胡钧凯王秀芳东北石油大学电气信息工程学院

在利用可调谐半导体激光吸收光谱技术探测甲烷气体泄漏时,复杂的环境光干扰会降低浓度检测信号的信噪比使波形失真。为了抑制噪声,增强电信号与浓度值的线性相关度,提出一种以VisuShrink方法改善小波阈值函数的小波阈值去噪算法。该算... 详细信息

在利用可调谐半导体激光吸收光谱技术探测甲烷气体泄漏时,复杂的环境光干扰会降低浓度检测信号的信噪比使波形失真。为了抑制噪声,增强电信号与浓度值的线性相关度,提出一种以VisuShrink方法改善小波阈值函数的小波阈值去噪算法。该算法针对小波阈值去噪算法的软硬度不能平衡信号,存在失真的问题,利用统计方法对阈值进行计算,弱化间断点阈值跳变影响。通过仿真计算对比未加噪声前的信号与滤波后的信号,提出算法的信噪比为28.405 30,优于四阶巴特沃斯滤波器。VisuShrink方法在SNR和NCC参数上性能远优于巴特沃斯滤波器,与软阈值函数相近,在MSE均方误差分析上远小于软阈值精度,与巴特沃斯相近,具有较好的平滑特性。实际搭建检测平台对多个浓度样本采样进行多次采样,采用VisuShrink方法设计的滤波器将系统误差精度从4.14%提升至2.472%,算法可有效用于甲烷检测系统提高光谱数据的平滑性和准确性。

关键词：可调谐半导体激光吸收光谱气体浓度测量波长调制光谱技术小波阈值去噪甲烷泄漏

Dynamic impedance of piles in visco-elastic material considering axial loads

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Journal of Central South University of Technology 2005年第Z1期12卷 162-167页

作者： jiang jian-guo ZHOU Xu-hong ZHANG Jia-sheng School of Civil Engineering and Architecture Central South University Changsha 410075 China School of Civil Engineering and Architecture Chang''an University Xi''an 710064 China School of Civil Engineering and Architecture Central South University Changsha 410075 China

The dynamic impedance function of pile in visco-elastie material considering axial loads under lateral dynamic force was analyzed, and the beam dynamic differential equation was used to induce the dynamic impedance function. After analyzing the edge conditions, the dynamic impedance functions were deduced. Contrasted with the result that does not consider axial loads, the axial loads have obvious influence on the dynamic impedance *** the results show that the dimensionless prarmeter of the dynamic impedance will change from 6 % to 9 % when considering axial loads, and dimensionless prarmeter of the dynamic impedance of the coupling horizontal-sway will increase by 31 %.

关键词： impedance function dynamic analysis axial loads

Physical neural networks with self-learning capabilities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 23-42页

作者： Weichao Yu Hangwen guo jiang Xiao jian Shen State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Department of Physics Fudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Physical neural networks are artificial neural networks that mimic synapses and neurons using physical systems or *** networks harness the distinctive characteristics of physical systems to carry out computations effectively,potentially surpassing the constraints of conventional digital neural networks.A recent advancement known as“physical self-learning”aims to achieve learning through intrinsic physical processes rather than relying on external *** article offers a comprehensive review of the progress made in implementing physical self-learning across various physical *** learning strategies that contribute to the realization of physical self-learning are *** challenges in understanding the fundamental mechanism of learning,this work highlights the progress towards constructing intelligent hardware from the ground up,incorporating embedded self-organizing and self-adaptive dynamics in physical systems.

关键词： self-learning physical neural networks neuromorphic computing physical learning

Variability Analysis for a Two-station Queueing Network in Heavy Traffic with Arrival Processes Driven by Queues

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 445-466页

作者： jian CAO Yong-jiang guo Kai-ming YANG School of Science Beijing University of Posts and TelecommunicationsBeijing 100876China

The law of the iterated logarithm(LIL)for the performance measures of a two-station queueing network with arrivals modulated by independent queues is developed by a strong approximation *** convenience,two arrival processes modulated by queues comprise the external system,all others are belong to the internal *** is well known that the exogenous arrival has a great influence on the asymptotic variability of performance measures in *** the considered queueing network in heavy traffic,we get all the LILs for the queue length,workload,busy time,idle time and departure processes,and present them by some simple functions of the primitive *** LILs tell us some interesting insights,such as,the LILs of busy and idle times are zero and they reflect a small variability around their fluid approximations,the LIL of departure has nothing to do with the arrival process,both of the two phenomena well explain the service station’s situation of being busy all the *** external system shows us a distinguishing effect on the performance measures:an underloaded(overloaded,critically loaded)external system affects the internal system through its arrival(departure,arrival and departure together).In addition,we also get the strong approximation of the network as an auxiliary result.

关键词： two-station queueing network the law of the iterated logarithm(LIL) strong approximation fluid approximation

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan jiang Liang-Liang Wei jian He Hong-Bo guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

Passivity-based control of synchronous motors in mine hoist systems

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Journal of Coal Science & Engineering(China) 2009年第3期15卷 332-336页

作者： XUE Hua jiang jian-guo YUAN Ming-han jiang Hua School of Electronics and Electric Engineering Shanghai Jiao Tong University Shanghai 200030 China Shanghai University of Electric Power Shanghai 200090 China

An adaptive PBC strategy for SM with a time-varying load torque to track fluxand speed trajectories was *** key point of this method was the identificationof terms,known as workless forces,which appeared in the dynamic equations of SM buthad no effect on the energy balance equation of the closed ***,combined withadaptive control schemes,not only preserved the advantages of PBC such as nonexistenceof singularity,but also rejected the flux and speed tracking error caused by statorand rotor resistance *** rotor currents of SM were estimated via a state *** algorithm simplified the control structure and enhanced the robustness of thecontrol *** feasibility and effectiveness were confirmed by experimental resultsbased on dSPACE.

关键词： passivity-based control(PBC) adaptive scheme synchronous motors(SM) dSPACE