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Particuology 2015年第2期13卷 27-34页

作者： Jun li Xinwei liu li zhou Qingshan Zhu Hongzhong li State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of Sciences

A novel two-stage reduction process for synthesis of ultrafine nickel powder with a high purity and low density in a fluidized bed reactor has been developed in this work. The raw ultraflne NiO particles are first pre-reduced using hydrogen at lower temperatures （340-400 ℃）, followed by further reduction at higher temperatures （500-600℃）. The self-agglomeration of Ni particles formed during low-temperature reduction decreases the sintering activity of the newly formed ultrafine Ni particles, leading to good fluidization quality, even for the subsequent high-temperature reduction process. The agglomerated Ni particles have a high Ni content （above 99wt%）, a low density （0.78g/cm^3） and a uniform particle size （approximately 100 μm）. A concept design for a novel two-stage fluidized bed reactor process used to produce high-purity Ni powder was also proposed. This approach may be extended to the synthesis of other ultrafine/nanosized metals or metal oxides through a fluidization method.

关键词： Ultrafine Ni powder Production Fluidized bed reactor Two-stage reduction

Quantification of restricting factors of agricultural development in Min County of Gansu, China

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Journal of Mountain Science 2020年第1期17卷 147-155页

作者： CHEN Yong zhou li-hua Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China

Agricultural development in povertystricken areas is a major problem affecting agricultural modernization in China. This study discusses the restrictive factors affecting agricultural development in impoverished areas in China. A typical impoverished mountainous area, Min County,was selected for a case study. A regression analysis on the factors and characteristics of agricultural development in Min County between 1982 and 2017 was performed in this study. Taking agricultural output as the dependent variable, we selected nine main inputs of agricultural production in impoverished mountainous areas as the independent variables. Ridge regression analysis was carried out by testing for unit root and co-integration to verify the equilibrium relationship of the data. The results showed that the real Gross domestic product(GDP)per capita, the non-grain area ratio, the proportion of government expenditure on agriculture support to total expenditure, and the amount of chemical fertilizer applied in unit cultivated land area were the four most significant factors. The proportion of government expenditure on agriculture support to total expenditure was a negative influence, whereas the other three significant factors had a positive influence on agricultural output. This study highlights about the most significant factors affecting the agricultural development of impoverished mountainous regions in China.

关键词： Impoverished mountainous region Agricultural development Min County Ridge regression

Dynamical Feedback between Synoptic Eddy and Low-Frequency Flow as Simulated by BCC_CSM1.1(m)

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Advances in Atmospheric Sciences 2017年第11期34卷 1316-1332页

作者： Fang zhou Hong-li REN Laboratory for Climate Studies National Climate CenterChina Meteorological Administrationbeijing 100081china CMA-NJU Joint Laboratory for Climate Prediction Studies School of Atmospheric SciencesNanjing Universitynanjing 210093china Department of Atmospheric Science School of Environmental StudiesChina University of Geosciencewuhan 430074china

Since the interaction between atmospheric synoptic eddy （SE）（2-8 days） activity and low-frequency （LF）（monthly） flow （referred to as SELF） plays an essential role in generating and maintaining dominant climate modes, an evaluation of the performance of BCC_CSMI.I（m） in simulating the SE feedback onto the LF flow is given in this paper. The model captures well the major spatial features of climatological eddy vorticity forcing, eddy-induced growth rate, and patterns of SELF feedback for the climate modes with large magnitudes in cold seasons and small magnitudes in warm seasons for both the Northern and Southern Hemisphere. As in observations, the eddy-induced growth rate and SELF feedback patterns in the model also show positive SE feedback. Overall, the relationships between SE and LF flow show that BCC_CSM1. l（m） satisfactorily captures the basic features of positive SE feedback, which demonstrates the simulation skill of the model for LF variability. Specifically, such an evaluation can help to find model biases of BCC_CSM1.1 （m） in simulating SE feedback, which will provide a reference for the model＇s application.

关键词： model evaluation synoptic eddy feedback simulation eddy vorticity forcing eddy-induced growth rate patternsof synoptic eddy feedback

Phase-Sensitive Optical Time-Domain Reflectometry Amplified by Gated Raman Pump

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Photonic Sensors 2015年第4期5卷 345-350页

作者： Yi li Yi zhou li ZHANG Mengqiu FAN Jin li Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education) University of Electronic Scienceand Technology of China Chengdu 611731 China

A long-range phase-sensitive optical time-domain reflectometry is proposed and experimentally demonstrated, based on the gated Raman amplification （RA）. This technique can reduce the amplified spontaneous emissions （ASE） noise of the Raman pump while extend the sensing distance. A direct-detection based phase-sensitive optical time-domain reflectometry （O-OTDR） with an operation range of 50 km and a spatial resolution of 20 m has been demonstrated. The influence of different delay time of the gated Raman pump on the O-OTDR system is also discussed.

关键词： Fiber optic sensors Rayleigh scattering stimulated Raman scattering

Adaptive integral dynamic surface control based on fully tuned radial basis function neural network

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Journal of Systems Engineering and Electronics 2010年第6期21卷 1072-1078页

作者： li zhou Shumin Fei Changsheng Jiang Key Laboratory of Measurement and Control of CES of Ministry of Education Southeast University Nanjing 210096 R R. China School of Automation Southeast University Nanjing 210096 R R. China College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 R R. China

An adaptive integral dynamic surface control approach based on fully tuned radial basis function neural network （FTRBFNN） is presented for a general class of strict-feedback nonlinear systems,which may possess a wide class of uncertainties that are not linearly parameterized and do not have any prior knowledge of the bounding *** is employed to approximate the uncertainty online,and a systematic framework for adaptive controller design is given by dynamic surface control. The control algorithm has two outstanding features,namely,the neural network regulates the weights,width and center of Gaussian function simultaneously,which ensures the control system has perfect ability of restraining different unknown uncertainties and the integral term of tracking error introduced in the control law can eliminate the static error of the closed loop system effectively. As a result,high control precision can be *** signals in the closed loop system can be guaranteed bounded by Lyapunov ***,simulation results demonstrate the validity of the control approach.

关键词： adaptive control integral dynamic surface control fully tuned radial basis function neural network.

Hydrolysis Process of the Anticancer Agents Novel Non-classical trans-Platinum(Ⅱ) with Aliphatic Amines

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Chinese Journal of Structural Chemistry 2007年第8期26卷 962-972页

作者： YUAN Qing-Hui zhou li-Xin Department of Chemistry Jinan University Guangzhou Guangdong 510632 China

The hydrolysis process of the anticancer agents novel non-classical transplatinum（ Ⅱ ） with aliphatic amines and the influence of solvent models therein have been studied by using hybrid density functional theory （B3LYP）. In this study, the stepwise hydrolysis, trans[PtCl2（Am）（isopropylamine）] ＋ 2H2O → trans-[Pt（Am）（isopropylamine）（OH2）2]^2＋＋ 2Cl^-, was explored. Implicit solvent effects were incorporated through polarized continuum models. The stationary points on the potential energy surfaces for the first and second hydrolysis steps,proceeding via a general SN2 pathway, were fully optimized and characterized. It was found that the first hydrolysis reaction is easier than the second one and the hydrolysis of trans- [PtCl2-（isopropylamine）2] is the easiest in our studying systems. The result can assist in under- tanding the hydrolysis mechanism of trans-[PtCl2（Am）（isopropylamine）] and designing novel Pt-based anticancer drugs.

关键词： hydrolysis DFT non-classical trans-platinum aliphatic amines transition state

Photocatalytic degradation of perfluorooctanoic acid with β-Ga_2O_3 in anoxic aqueous solution

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Journal of Environmental Sciences 2012年第4期24卷 774-780页

作者： Baoxiu Zhao Mou Lv li zhou School of Environmental and Municipal Engineering Qingdao Technological UniversityQingdao 266033China State Key Joint Laboratory of Environment Simulation and Pollution Control Department of Environmental Science and EngineeringTsinghua UniversityBeijing 100084China

Perfluorooctanoic acid （PFOA） is a new-found hazardous persistent organic pollutant, and it is resistant to decomposition by hydroxyl radical （HO.） due to its stable chemical structure and the high electronegativity of fluorine. Photocatalytic reduction of PFOA with β-Ga2O3 in anoxic aqueous solution was investigated for the first time, and the results showed that the photoinduced electron （ecb） coming from the β-Ga2O3 conduction band was the major degradation substance for PFOA, and shorter-chain perfluorinated carboxylic acids （PFCAs, CnF2n＋1COOH, 1 ≤ n ≤ 6） were the dominant products. Furthermore, the concentration of F- was measured by the IC technique and defluorination efficiency was calculated. After 3 hr, the photocatalytic degradation efficiency was 98.8% and defluorination efficiency was 31.6% in the presence of thiosulfate and bubbling N2. The degradation reaction followed first-order kinetics （k = 0.0239 min-1, t1/2 = 0.48 hr）. PFCAs （CnF2n＋xCOOH, 1 ≤ n≤ 7） were detected and measured by LC-MS and LC-MS/MS methods. It was deduced that the probable photocatalytic degradation mechanism involves ec-b attacking the carboxyl of CnF2n＋1COOH, resulting in decarboxylation and the generation of CnFzn＋1. The produced CnF2n＋1 reacted with H2O, forming CnF2n＋1OH, then CnF2n＋1OH underwent HF loss and hydrolysis to form CnF2,＋1COOH.

关键词： perfluorooctanoic acid β-Ga2O3 photocatalytic degradation defluorination photoinduced electron

Machining Characteristics in Cryogenic Grinding of SiCp/Al Composites

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 869-874页

作者： li zhou Shutao Huang Xiaolin Yu School of Mechanical Engineering Shenyang Ligong University

In this study, liquid nitrogen was applied to grind SiCp/Al composites with high volume fraction and large SiC particle at different levels of cutting conditions, and the effects of grinding depth and speed on grinding force, surface morphology, and surface roughness were investigated. At the same time, the effect of cryogenic cooling was also compared with that of conventional wet grinding. The experimental results indicated that cryogenic cooling is effective in enhancing supporting function of Al matrix to the SiC particles and improving surface quality. Additionally, the brittle fracture of SiC particles was suppressed and some ductile streaks on SiC particle could be observed.

关键词： SiCp/Al composites Grinding Cryogenic machining Surface quality

Multilayer ANN indoor location system with area division in WLAN environment

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Journal of Systems Engineering and Electronics 2010年第5期21卷 914-926页

作者： Mu zhou Yubin Xu li Tang School of Electronics and Information Engineering Harbin Institute of Technology Harbin 150001 P. R. China

An indoor location system based on multilayer artificial neural network（ANN） with area division is *** characteristics of recorded signal strength（RSS）,or signal to noise ratio（SNR） from each available access points（APs）,are utilized to establish the radio map in the off-line *** in the on-line phase,the two or three dimensional coordinates of mobile terminals（MTs） are estimated according to the similarity between the new recorded RSS or SNR and fingerprints pre-stored in radio *** the feed-forward ANN with three layers is sufficient to describe any nonlinear mapping relationship between inputs and outputs with finite discontinuous points,the efficient inputs for better training performances are difficult to be determined because of complex and dynamic indoor ***,the discussion of distance relativity for different signal characteristics and optimal strategies for multi-mode phenomenon avoidance is *** also,the feasibility and effectiveness of this method are verified based on the experimental comparison with normal ANN without area division,K-nearest neighbor（KNN） and probability methods in typical office environment.

关键词： indoor location artificial neural network multilayer structure multi-mode relativity.

Programmable synthetic receptors:the next-generation of cell and gene therapies

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Signal Transduction and Targeted Therapy 2024年第2期9卷 376-400页

作者： Fei Teng Tongtong Cui li zhou Qingqin Gao Qi zhou Wei li University of Chinese Academy of Sciences Beijing 101408China State Key Laboratory of Stem Cell and Regenerative Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Institute for Stem Cell and Regeneration Chinese Academy of SciencesBeijing 100101China Beijing Institute for Stem Cell and Regenerative Medicine Beijing 100101China

Cell and gene therapies hold tremendous promise for treating a range of difficult-to-treat ***,concerns over the safety and efficacy require to be further addressed in order to realize their full *** receptors,a synthetic biology tool that can precisely control the function of therapeutic cells and genetic modules,have been rapidly developed and applied as a powerful *** designed and engineered,they can be applied to finetune the therapeutic activities,i.e.,to regulate production of dosed,bioactive payloads by sensing and processing user-defined signals or *** review provides an overview of diverse synthetic receptor systems being used to reprogram therapeutic cells and their wide applications in biomedical *** a special focus on four synthetic receptor systems at the forefront,including chimeric antigen receptors(CARs)and synthetic Notch(synNotch)receptors,we address the generalized strategies to design,construct and improve synthetic ***,we also highlight the expanding landscape of therapeutic applications of the synthetic receptor systems as well as current challenges in their clinical translation.

关键词： synthetic landscape payload