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Journal of Environmental Sciences 2012年第4期24卷 690-698页

作者： Yanchun Wang min Qiao Yunxia Liu Yongguan zhu State Key Laboratory of Reginal and Urban Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Beijing Institute of Landscape Architecture Beijing 100102China Key Laboratory of Urban Environment Health Institute of Urban EnvironmentChinese Academy of ScienceXiamen 361021China

The possible health risks of heavy metals contamination to local population through food chain were evaluated in Beijing and Tianjin city cluster, China, where have a long history of sewage irrigation. The transfer factors （TF） for heavy metals from soil to vegetables for six elements including Cu, Zn, Pb, Cr, As and Cd were calculated and the pollution load indexes （PLI） were also assessed. Results indicate that only Cd exceeded the maximum acceptable limit in these sites. So far, the heavy metal concentrations in soils and vegetables were all below the permissible limits set by the ministry of Environmental Protection of China and World Health Organization. The transfer factors of six heavy metals showed the trend as Cd 〉 Zn 〉 Cu 〉 Pb 〉 As 〉 Cr, which were dependent on the vegetable species. The estimated dietary intakes of Cu, Zn, Pb, Cr, As and Cd were far below the tolerable limits and the target hazard quotient （THQ） values were less than 1, which suggested that the health risks of heavy metals exposure through consuming vegetables were generally assumed to be safe.

关键词： heavy metals soil transfer factor human health risk wastewater irrigation

A data-derived soft-sensor method for monitoring effluent total phosphorus

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Chinese Journal of Chemical Engineering 2017年第12期25卷 1791-1797页

作者： Shuguang zhu Honggui Han min Guo Junfei Qiao College of Electronic Information & Control Engineering Beijing University of Technology Beijing 100124 China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing 100124 China Engineering Research Center of Digital Community Ministry of Education Beijing 100124 China Beijing Laboratory for Urban Mass Transit Beijing 100124 China

The effluent total phosphorus(ETP) is an important parameter to evaluate the performance of wastewater treatment process(WWTP). In this study, a novel method, using a data-derived soft-sensor method, is proposed to obtain the reliable values of ETP online. First, a partial least square(PLS) method is introduced to select the related secondary variables of ETP based on the experimental data. Second, a radial basis function neural network(RBFNN) is developed to identify the relationship between the related secondary variables and ETP. This RBFNN easily optimizes the model parameters to improve the generalization ability of the soft-sensor. Finally, a monitoring system, based on the above PLS and RBFNN, named PLS-RBFNN-based soft-sensor system, is developed and tested in a real WWTP. Experimental results show that the proposed monitoring system can obtain the values of ETP online and own better predicting performance than some existing methods.

关键词： Data-derived soft-sensor Effluent total phosphorus Wastewater treatment process Radial basis function neural network Partial least square method

Data-driven intelligent monitoring system for key variables in wastewater treatment process

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2093-2101页

作者： Honggui Han Shuguang zhu Junfei Qiao min Guo College of Electronic Information & Control Engineering Beijing University of Technology Beijing 100124 China Beijing Key Laboratory of Computational Intelligence and Intelligent System Beijing 100124 China Engineering Research Center of Digital Community Ministry of Education Beijing 100124 China Beijing Laboratory for Urban Mass Transit Beijing 100124 China

In wastewater treatment process(WWTP), the accurate and real-time monitoring values of key variables are crucial for the operational strategies. However, most of the existing methods have difficulty in obtaining the real-time values of some key variables in the process. In order to handle this issue, a data-driven intelligent monitoring system, using the soft sensor technique and data distribution service, is developed to monitor the concentrations of effluent total phosphorous(TP) and ammonia nitrogen(NH_4-N). In this intelligent monitoring system, a fuzzy neural network(FNN) is applied for designing the soft sensor model, and a principal component analysis(PCA) method is used to select the input variables of the soft sensor model. Moreover, data transfer software is exploited to insert the soft sensor technique to the supervisory control and data acquisition(SCADA) system. Finally, this proposed intelligent monitoring system is tested in several real plants to demonstrate the reliability and effectiveness of the monitoring performance.

关键词： Data-driven Soft sensor Intelligent monitoring system Data distribution service Wastewater treatment process

Possibility of an Optically-Trapped Bose-Einstein Condensation

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Chinese Physics Letters 1999年第5期16卷 350-352页

作者： YIN Jian-ping Yifu zhu WANG Yu-zhu min Xiao Department of Physics Suzhou UniversitySuzhou215006 Department of Physics Florida International University MiamiFlorida 33199USA Laboratory for Quantum Optics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800 Department of Physics University of ArkansasFayettevilleAR 72701USA

We propose a novel gravito-optical atom trap composed of a blue-detuned,conical dark-hollow-beam propagating upward and the gravity *** cold atoms are loaded into the conical dark-hollow-beam from a magnetic-optical trap and bounce inside the hollow beam,they experience an efficient hollow-beam induced Sisyphus cooling and repurnping-beam induced geometric *** investigation shows that an ultracold and dense 87Rb atomic sample with an equilibrium 3D temperature of about 1μK can be obtained and the appearance of an optically-trapped Bose-Einstein condensation may be possible in this pure optical trap.

关键词： field. Einstein beam

The governance technology for blockchain systems:a survey

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Frontiers of Computer Science 2024年第2期18卷 181-197页

作者： Guocheng zhu Debiao HE Haoyang AN min LUO Cong PENG School of Cyber Science and Engineering Wuhan UniversityWuhan 430072China Shandong Provincial Key Laboratory of Computer Networks Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China

After the Ethereum DAO attack in 2016,which resulted in significant economic losses,blockchain governance has become a prominent research ***,there is a lack of comprehensive and systematic literature review on blockchain *** deeply understand the process of blockchain governance and provide guidance for the future design of the blockchain governance model,we provide an in-depth review of blockchain *** this paper,first we introduce the consensus algorithms currently used in blockchain and relate them to governance ***,we present the main content of off-chain governance and investigate two well-known off-chain governance ***,we investigate four common on-chain governance voting techniques,then summarize the seven attributes that the on-chain governance voting process should meet,and finally analyze four well-known on-chain governance blockchain projects based on the previous *** hope this survey will provide an in-depth insight into the potential development direction of blockchain governance and device future research agenda.

关键词： blockchain governance off-chain governance on-chain governance voting

Apoptosis of rabbit retinal cell after eyeball rupture

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Asian Pacific Journal of Tropical Medicine 2013年第4期6卷 273-279页

作者： Xue-min Tian Yu zhu Department of Ophthalmology the First Affiliated Hospital of Zhengzhou University

Objective:To establish rabbit eyeball rupture model by air gun in order to observe and analyze the early injury condition and reasons of retinal cell after eyeball ***:Forty eight healthy rabbits were randomly divided into control group and 1,3,6,12 and 24 h after injury *** anesthesia,the rabbit eyeball rupture model was established by air gun. Then the early pathological changes of rabbit retina were observed,and apoptotic index(Al), oncosis index(OI),the relationship between the expression amounts of apoptosis-related genes and Al were ***:Obvious pathological lesion appeared in retina 6 h after injury. Irreversible damage occurred 12-24 h after *** results of AI and OI indicated that the OI peak appeared 6 h after injury and then gradually declined,while the AI increased with the prolongation of time,and the AI was higher than OI in 12 h after *** results indicated that there was no obvious bcl-2 protein expression *** with the control group and the 3,6,12 and 24 h after the injury groups,the expressions of p53 and Caspase-3 were significandy improved and peaked at 12 h(P<0.01).Positive correlation existed among p53,Caspase-3 expression amount and cell apoptosis ***:Apoptosis and oncosis of visual cells are the main reasons of retinal cell injury.p53 and Caspase-3 are the important factors in promoting the retinal cell apoptosis after eyeball rupture.

关键词： Rabbit eyeball rupture Retinopathy Cell apoptosis bcl-2 p53 Caspase-3

Challenges in Atomic-Scale Characterization of High-k Dielectrics and Metal Gate Electrodes for Advanced CMOS Gate Stacks

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Journal of Materials Science & Technology 2009年第3期25卷 289-313页

作者： Xinhua zhu Jian-min zhu Aidong Li Zhiguo Liu Naiben ming National Laboratory of Solid State Microstructures Department of Physics Nanjing University Nanjing 210093 China

The decreasing feature sizes in complementary metal-oxide semiconductor （CMOS） transistor technology will require the replacement of SiO2 with gate dielectrics that have a high dielectric constant （high-k） because as the SiO2 gate thickness is reduced below 1.4 nm, electron tunnelling effects and high leakage currents occur in SiO2, which present serious obstacles to future device reliability. In recent years significant progress has been made on the screening and selection of high-k gate dielectrics, understanding their physical properties, and their integration into CMOS technology. Now the family of hafnium oxide-based materials has emerged as the leading candidate for high-k gate dielectrics due to their excellent physical properties. It is also realized that the high-k oxides must be implemented in conjunction with metal gate electrodes to get sufficient potential for CMOS continue scaling. In the advanced nanoscale Si-based CMOS devices, the composition and thickness of interfacial layers in the gate stacks determine the critical performance of devices. Therefore, detailed atomic- scale understandings of the microstructures and interfacial structures built in the advanced CMOS gate stacks, are highly required. In this paper, several high-resolution electron, ion, and photon-based techniques currently used to characterize the high-k gate dielectrics and interfaces at atomic-scale, are reviewed. Particularly, we critically review the research progress on the characterization of interface behavior and structural evolution in the high-k gate dielectrics by high-resolution transmission electron microscopy （HRTEM） and the related techniques based on scanning transmission electron microscopy （STEM）, including high-angle annular dark- field （HAADF） imaging （also known as Z-contrast imaging）, electron energy-loss spectroscopy （EELS）, and energy dispersive X-ray spectroscopy （EDS）, due to that HRTEM and STEM have become essential metrology tools for characterizing the d

关键词： High-k gate dielectrics Metal gate electrodes, CMOS gate stack HRTEM STEM

Some Exact Solutions of Variable Coefficient Cubic-Quintic Nonlinear Schrdinger Equation with an External Potential

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Communications in Theoretical Physics 2009年第3期51卷 391-394页

作者： zhu Jia-min LIU Yu-Lu Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China Yiwu Industrial and Commercial College Yiwu 322000 China

By constructing appropriate transformations and an extended elliptic sub-equation approach, we find some exact solutions of variable coefficient cubic-quintie nonlinear Schrodinger equation with an external potential, which include bell and kink profile solitary wave solutions, singular solutions, triangular periodic wave solutions and so on.

关键词： cubic-quintic nonlinear Schrodinger equation variable coefficient exact solution

Comparison of Grain Size in Plain Carbon Hot-Rolled Sheets Manufactured by CSP and Conventional Rolling Processing

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Journal of Iron and Steel Research International 2012年第1期19卷 17-22页

作者： zhu Xue-song zhu Guo-hui MAO Wei-min School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China School of Materials Science and Engineering Anhui University of Technology Ma＇anshan 243002 Anhui China

Average grain size and grain size distribution in as hot-rolled SPHC, SPHD, and SPHE sheets manufac- tured by compact strip production （CSP） processing and traditional continuous casting and rolling （CCR） processing respectively were investigated by quantitative metallographic method. The results show that the average grain size and distribution width of grain size in sheets manufactured by CSP processing was obviously larger than that by CCR processing. It was analyzed that multi-phase transformation and high reduction ratio in CCR processing resulted in refining grain size, which would be dominant reason for controlling grain size. In plain carbon steels such as SPHC, SPHD and SPHE, the effect of fine precipitation in CSP on behavior of deformation and recrystallization of austenite during roiling, and consequent refinement of grain size seem not to be as important as the effect of reheating and roughing in CCR processing. Homogenizing in reheating and refining grain size in roughing in CCR processing would refine final grain size and also make grain size homogenized, Very coarse grain size would result in mixed grain size, large distribution width of grain size due to interaction of static and dynamic recrystallization in CSP processing

关键词： CSP CCR hot-rolled plate grain size

Groove formation on Phobos from reimpacting orbital ejecta of the Stickney crater

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Earth and Planetary Physics 2022年第3期6卷 294-303页

作者： XiangYu Xi min Ding MengHua zhu State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacaoChina China National Space Administration Macao Center for Space Exploration and ScienceMacaoChina

Numerous linear grooves have long been recognized as covering the surface of Phobos, but the mechanisms of their formation are still unclear. One possible mechanism is related to the largest crater on Phobos, the Stickney crater, whose impact ejecta may slide,roll, bounce, and engrave groove-like features on Phobos. When the launch velocity is higher than the escape velocity, the impact ejecta can escape Phobos. A portion of these high-velocity ejecta are dragged by the gravitational force of Mars, fall back, and reimpact *** this research, we numerically test the hypothesis that the orbital ejecta of the Stickney crater that reimpact Phobos could be responsible for a particular subset of the observed grooves on Phobos. We adopt impact hydrocode i SALE-2 D(impact-Simplified Arbitrary Lagrangian Eulerian, two-dimensional) to simulate the formation of the Stickney crater and track its impact ejecta, with a focus on orbital ejecta with launch velocities greater than the escape velocity of Phobos. The launch velocity distribution of the ejecta particles is then used to calculate their trajectories in space and determine their fates. For orbital ejecta reimpacting Phobos, we then apply the sliding boulder model to calculate the ejecta paths, which are compared with the observed groove distribution and length to search for causal relationships. Our ejecta trajectory calculations suggest that only ~1% of the orbital ejecta from the Stickney crater can reimpact Phobos. Applying the sliding boulder model, we predict ejecta sliding paths of 9-20 km in a westward direction to the east of the zone of avoidance, closely matching the observed grooves in that region. The best-fit model assumes an ejecta radius of ~150 m and a speed restitution coefficient of 0.3, consistent with the expected ejecta and regolith properties. Our calculations thus suggest the groove class located to the east of the zone of avoidance may have been caused by reimpact orbital ejecta from the Stick

关键词： Phobos groove formation Stickney crater reimpact ejecta