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Mobilities and leachabilities of heavy metals in sludge with humus soil

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Journal of Environmental Sciences 2011年第2期23卷 247-254页

作者： rui Zhu min Wu Jian Yang State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China.

Chemical forms of Zn, Ni, Cu, and Pb in municipal sewage sludge were investigated by adding humus soil to sludge and by performing sequential extraction procedures. In the final sludge mixtures, Zn and Ni were mainly found in Fe/Mn oxide-bound （F3） and organic matter/sulfide-bound （F4） forms. For Zn, exchangeable （F1）, carbonate-bound （F2）, and F3 forms were transformed to F4 and residual forms （F5）. For Ni, F1 and F2 forms were transformed to F1, F2, and F3 forms. Both Cu and Pb were strongly associated with the stable forms F4 and F5. For Cu, F2 and F3 forms were major contributors, while for Pb, F3 and F4 forms were major contributors to F5. Humus soil dosage and pH conditions in the sludge were strongly correlated with the forms of heavy metals. Five forms were used to evaluate metal mobilities in the initial and final sludge mixtures. The mobilities of the four heavy metals studied decreased after 28 days. The metal mobilities in the final sludge mixtures were ranked in the following order： Ni 〉 Zn 〉 Cu = Pb. Leaching tests showed that the mobilities of Zn and Ni in lower pH conditions （pH 4） were higher than those in higher pH conditions （pH 8）.

关键词： sludge heavy metal humus soil mobility leachability

High resolution wide swath revisit synthetic aperture radar imaging mode and algorithm

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Journal of Systems Engineering and Electronics 2015年第2期26卷 274-281页

作者： Weihua Zuo Yiming Pi rui min School of Electronic Engineering University of Electronic Science and Technology of China Department of Physics and Information Engineering Huaihua University

Based on the squint mode, a high resolution wide swath revisit synthetic aperture radar （SAR） imaging mode is pro- posed. The transmitting antennas are configured as the single phase center multiple azimuth beams （SPC MAB）. The formed two beams point to two different directions to obtain two images of the observed scenario. The receiving antennas are configured as displaced phase center multiple azimuth beams （DPC MAB） to decrease the required pulse repetition frequency （PRF）. The de- creased PRF can ensure the high resolution wide swath imaging. Based on the analysis of the character of the return signal, a pro- cessing method named multiple beam multiple channel algorithm （MBMCA） is proposed to separate the aliased sub-beams＇ echoes. The separated echoes are focused respectively to get the revisit imaging to the observed scenario. The simulation experiments ve- rify the validity and correctness of the proposed imaging mode and processing algorithm.

关键词： synthetic aperture radar(SAR) high resolution wide swath revisit

Dramatic thinning of Alaskan river ice and its climatic controls

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Advances in Climate Change Research 2022年第5期13卷 623-631页

作者： rui-min YANG Tingjun ZHANG Key Laboratory of Western China’s Environmental Systems(ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China School of Agriculture and Forestry Economics and Management Lanzhou University of Finance and EconomicsLanzhou 730020China

River ice thickness(RIT)directly influences human activities,such as rural transportation and subsistence activities,in addition to ecosystem and hydrology processes in the *** of RIT response to the rapid Arctic warming is very limited or essentially *** scientific objective of this study is to investigate changes and variations in RIT and their response to rapid Arctic *** used ground-based measurements of 45 river gauge sites from 1961 through 2015 spanning 12 river basins across *** results indicate that the long-term mean maximum river ice thickness(MRIT)ranged from 40.3±12.7 cm in the southeast to 187.3±31.9 cm in northwest *** decreased dramatically from 1961 to 2015,on average,at a rate of−0.26±0.17 cm per year,and RIT declined significantly in all months from October through March,and more rapidly in winter than in autumn and *** impacts of air temperature and snowfall on MRIT change were analysed,and their relative influences were 74%and 26%,***,an increase in air temperature was the primary factor contributing to MRIT decrease,while increasing snowfall,and snow on river ice enhanced MRIT ***,snowfall was the primary regulator for thickness change and higher air temperature resulted in RIT declining in autumn,while ice thickness decrease was mostly driven by warming in ***,neither air temperature nor snowfall is the primary control factor for declining RIT in winter,and further work needs to be done to detect the reason.

关键词： River ice Global warming Arctic rapid change Alaska Arctic

Study on inherent neutron sources in MSR

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Nuclear Science and Techniques 2018年第4期29卷 146-154页

作者： rui-min Ji Cheng-Gang Yu ming-Hai Li rui Yan Yang Zou Gui-min Liu Shanghai Institute of Applied Physics Chinese Academy of Sciences Jiading Campus Shanghai 201800 China University of Chinese Academy of Sciences Beijing 100049China

The molten salt reactor(MSR) has received much recent attention. The presence of beryllium and the mixing of actinides with light nuclei in the fuel salt result in a relatively strong neutron source that can affect the surveillance at subcritical and transient characteristics during operation. In this study, we predict the inherent neutron sources based on a MSR model. The calculation shows that in the fresh core, the inherent neutron sources are mainly from alpha-induced neutrons. After power operation, the inherent neutron sources become remarkably stronger due to photoneutrons. Although being an insignificant part in the total neutron population during operation, the inherent neutron sources can be used as the installed neutron source after shutdown. If the MSR has continuously operated at full power(2 MWt) for 10 days,then there would be no need for the installed source within80 days after shutdown. After operating constantly for500 days, the installed neutron source can be eliminated within 2 years after shutdown.

关键词： MSR Fuel salt Inherent neutron source Photoneutron Alpha-induced neutron

Impact of photoneutrons on reactivity measurements for TMSR-SF1

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Nuclear Science and Techniques 2017年第6期28卷 101-107页

作者： rui-min Ji ming-Hai Li Yang Zou Gui-min Liu Shanghai Institute of Applied Physics Chinese Academy of Sciences University of Chinese Academy of Sciences

The solid-fueled thorium molten salt reactor(TMSR-SF1) is a 10 MW_(th) test reactor design to be deployed in 5-10 years by the TMSR *** design combines coated particle fuel and molten FLiBe coolant for great intrinsic safety features and economic *** to a large amount of beryllium in the coolant salt,photoneutrons are produced by(y,n) reaction,hence the increasing fraction of effective delayed neutrons in the core by the photoneutrons originating from the long-lived fission *** of the delayed photoneutron groups are of long lifetime,so a direct effect is resulted in the transient process and reactivity *** study the impact of photoneutrons for TMSR-SF1,the effective photoneutron fraction is estimated using k-ratio method and performed by the Monte Carlo code(MCNP5) with ENDF/B-Ⅶ cross *** on the coupled neutronphoton point kinetics equations,influence of the photoneutrons is *** results show that the impact of photoneutrons is not negligible in reactivity *** considering photoneutrons in on-line reactivity measurement based on inverse point kinetics can result in overestimation of the positive reactivity and underestimation of the negative *** photoneutrons also lead to more waiting time for the doubling time *** the photoneutron precursors take extremely long time to achieve equilibrium,a "steady" power operation may not directly imply a "real" criticality.

关键词： TMSR-SF1 Delayed photoneutrons Coupled neutron-photon point kinetics Reactivity measurement

Average Error Bounds of Trigonometric Approximation on Periodic Wiener Spaces

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Acta Mathematica Sinica,English Series 2013年第3期29卷 535-546页

作者： Cheng Yong WANG rui min WANG Department of Mathematics Beijing JiaoTong University

In this paper, we study the approximation of identity operator and the convolution inte- gral operator Bm by Fourier partial sum operators, Fejer operators, Vallee--Poussin operators, Ces^ro operators and Abel mean op... 详细信息

关键词： Average error bounds trigonometric polynomial approximation periodic Wiener spaces

New hybrid model of proton exchange membrane fuel cell

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第5期8卷 741-747页

作者： WANG rui-min CAO Guang-yi ZHU Xin-jian Institute of Fuel Cell Department of Automation Shanghai Jiao Tong University Shanghai 200240 China

Model and simulation are good tools for design optimization of fuel cell systems. This paper proposes a new hybrid model of proton exchange membrane fuel cell (PEMFC). The hybrid model includes physical component and black-box com-ponent. The physical component represents the well-known part of PEMFC, while artificial neural network (ANN) component estimates the poorly known part of PEMFC. The ANN model can compensate the performance of the physical model. This hybrid model is implemented on Matlab/Simulink software. The hybrid model shows better accuracy than that of the physical model and ANN model. Simulation results suggest that the hybrid model can be used as a suitable and accurate model for PEMFC.

关键词： Proton exchange membrane fuel cell (PEMFC) Artificial neural network (ANN) Hybrid model Physical model

Hybrid intelligent PID control design for PEMFC anode system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 552-557页

作者： rui-min WANG Ying-ying ZHANG Guang-yi CAO Fuel Cell Institute Department of Automation Shanghai Jiao Tong University Shanghai 200030 China Institute of Oceanographic Instrument Shandong Academy of Science Qingdao 266001 China

Control design is important for proton exchange membrane fuel cell (PEMFC) generator. This work researched the anode system of a 60-kW PEMFC generator. Both anode pressure and humidity must be maintained at ideal levels during steady operation. In view of characteristics and requirements of the system, a hybrid intelligent PID controller is designed specifically based on dynamic simulation. A single neuron PI controller is used for anode humidity by adjusting the water injection to the hydrogen cell. Another incremental PID controller, based on the diagonal recurrent neural network (DRNN) dynamic identification, is used to control anode pressure to be more stable and exact by adjusting the hydrogen flow rate. This control strategy can avoid the coupling problem of the PEMFC and achieve a more adaptive ability. Simulation results showed that the control strategy can maintain both anode humidity and pressure at ideal levels regardless of variable load, nonlinear dynamic and coupling characteristics of the system. This work will give some guides for further control design and applications of the total PEMFC generator.

关键词： Proton exchange membrane fuel cell (PEMFC) Anode system Single neuron Diagonal recurrent neural network (DRNN) PID controller

Using Entropy Based Mean Shift Filter and Modified Watershed Transform for Grain Segmentation

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International Journal of Automation and computing 2015年第2期12卷 199-207页

作者： Kun Zhang min-rui Fei Hui-Yu Zhou Shanghai Key Laboratory of Power Station Automation Technology School of Mechatronic Engineering and AutomationShanghai University The Institute of Electronics Communications and Information TechnologyQueen's University Belfast

Life science research aims to continuously improve the quality and standard of human life. One of the major challenges in this area is to maintain food safety and security. A number of image processing techniques have been used to investigate the quality of food products. In this paper, we propose a new algorithm to effectively segment connected grains so that each of them can be inspected in a later processing stage. One family of the existing segmentation methods is based on the idea of watersheding, and it has shown promising results in practice. However, due to the over-segmentation issue, this technique has experienced poor performance in various applications, such as inhomogeneous background and connected targets. To solve this problem, we present a combination of two classical techniques to handle this issue. In the first step, a mean shift filter is used to eliminate the inhomogeneous background,where entropy is used to be a converging criterion. Secondly, a color gradient algorithm is used in order to detect the most significant edges, and a marked watershed transform is applied to segment cluttered objects out of the previous processing stages. The proposed framework is capable of compromising among execution time, usability, efficiency and segmentation outcome in analyzing ring die pellets. The experimental results demonstrate that the proposed approach is effectiveness and robust.

关键词： Robust segmentation cluttered grains mean shift filter entropy modified marked watershed transform.