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Mesopolymer modified with palladium phthalocyaninesulfonate as a versatile photocatalyst for phenol and bisphenol A degradation under visible light irradiation

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Journal of Environmental Sciences 2013年第8期25卷 1687-1695页

作者： rong Xing Lin wu Zhenghao Fei Peng wu Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection Yancheng Teachers University Yancheng 224002 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

A novel versatile photocatalyst, FDU-PdPcS, was prepared by immobilizing palladium phthalocyaninesulfonate （PdPcS） onto the FDU-15 mesopolymer via multi-step chemical modification processes involving chloromethylation of the FDU-15 mesopolymer first with chloromethyl methyl ether, a subsequent amination reaction with ethylenediamine, and finally modification with palladium phthalocyaninesulfonate via ionic interaction. The obtained FDU-PdPcS photocatalyst was characterized by the X-ray diffraction （XRD）, UV-Vis spectrosopy and inductively coupled plasma （ICP） techniques. This photocatalyst not only affords a high dispersion of monomeric PdPcS molecules, which may further be stabilized by the π-electron of benzene rings of FDU-15, but also provides a number of diamino groups inside the mesopores, which could be advantageous for the photodegradation of phenolic pollutants. In photodegradation studies of phenolic pollutants, the FDU-PdPcS catalyst exhibited excellent visible light photocatalytic activity and reusability. The photodegradation products of phenol and bisphenol A were investigated by the gas chromatoghraphy-mass spectrometry （GC-MS） technique. The results showed that the photodegradation products were composed of carboxylic acids and CO2. Isopropanol, sodium azide and benzoquinone were used as hydroxyl radical （OH.）, singlet oxygen （1O2） and superoxide radical （O2.-） scavengers, respectively. The results suggested that 1O2 and O2. were the prominent active species during the photodegradation process. A possible mechanism for the photodegradation of phenol was also discussed.

关键词： mesopolymer phthalocyanine photocatalysis visible light phenolic pollutants

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Thermal insulation design of subsea vertical X-mas tree

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Petroleum Science 2021年第4期18卷 1182-1194页

作者： Xin rong Hong-wu Zhu College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Temperature drop is commonly observed in subsea vertical X-mas trees during *** presence of a huge temperature difference between internal crude oil and external seawater can cause severe equipment degradation of the oil flow channel(e.g.,hydrate precipitation),which can block the oil flow channel and interrupt the production *** most vulnerable parts of a subsea vertical X-mas tree tend to be components with high convective heat transfer rates,such as production modules and short *** proposed an innovative approach for the insulation design of underwater equipment under a shutdown ***,we obtained a heat transfer analysis of the tree under working conditions through computational fluid dynamics to ascertain the initial temperature condition for an unsteadystate ***,we investigated the unsteady heat transfer characteristics of the tree with an insulation layer in the shutdown state and derived the relationships between insulation duration and thickness by data *** used data analysis to identify the relationship between insulation duration and ***,we derived the empirical formula of insulation thickness for underwater equipment given the effect of environmental factors on the heat preservation *** performed the experiment with an oil pipeline,and the results showed that the internal oil of the equipment did not hydrate within 8 h under the shutdown condition with insulation layers.

关键词： Subsea vertical X-mas tree Thermal insulation design Unsteady heat-transfer analysis Computational fluid dynamics

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Examining the efficacy of revegetation practices in ecosystem restoration programs:insights from a hotspot of sandstorm in northern China

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Frontiers of Earth Science 2021年第4期15卷 922-935页

作者： Ziqiang DU rong rong Zhitao wu Hong ZHANG Institute of Loess Plateau Shanxi UniversityTaiyuan 030006China 2 Shanxi Key Laboratory for Ecological restoration of Loess Plateau Taiyuan 030006China Field Scientific Observation and Research Station of the Ministry of Education of Shanxi Subalpine Grassland Ecosystem Taiyuan 030006China College of Environmental&Resource Sciences Shanxi UniversityTaiyuan 030006China

Retrospectively evaluating the efficacy of revegetation practices is helpful in planning and imple-menting future ecosystem restoration programs(ERP).Having a good understanding of how human activities can affect vegetation cover,both before and after ERP,is particularly important in sandstorm hotspot *** Beijing-Tianjin Sandstorm Source Region(BTSSR)is one such *** conducted an investigation into vegetation dynamics within the *** was done using remote sensing data in conjunction with climate data sets and land use data spanning the 1982-2014 *** relationships between climatic factors(such as precipitation and temperature),and vegetative change were modeled using a neural network *** a process of residual analysis,the proportions of human-induced vegetative change both before and after the ERP were *** results show that:1)before the ERP(1982-2000),40.96%of the study area exhibited significantly progressive vegetation changes(p<0.05).This proportion decreased to encom-pass only 20.23%of the study area in the period following the ERP(2001-2014).2)89.55%of the study area showed signs of human-induced vegetation degradation before the *** 2001 and 2014 however,following ERP,this figure fell to only 27.78%.3)ERP implementation led to visible improvements in vegetative conditions within the BTSSR,especially in areas where ecological restoration measures were directly and anthropogenically *** results highlight the benefits that positive human action(i.e.,revegetation initiatives implemented under the framework of an ERP)have brought to the BTSSR.

关键词： vegetation dynamics human activities ERP neural network model Beijing-Tianjin sandstorm source region

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Evaluation of hepatocellular carcinoma using contrast-enhanced ultrasonography:correlation with microvessel morphology

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Hepatobiliary & Pancreatic Diseases International 2010年第6期9卷 605-610页

作者： Xiao, Ji-Dong Zhu, Wen-Hui Shen, shou-rong Cent S Univ Xiangya Hosp 3 Dept Diagnost Ultrasound Changsha 410013 Hunan Peoples R China Cent S Univ Xiangya Hosp 3 Dept Gastroenterol Changsha 410013 Hunan Peoples R China

BACKGROUND: Contrast-enhanced ultrasonography (CEUS) is an important technique for depiction and assessment of tumor vascularity. This study aimed to explore the relationship between the morphological characteristics of tumor microvessels and enhancement patterns on CEUS in hepatocellular carcinoma (HCC). METHODS: Eighty patients with HCC underwent CEUS using SonoVue before hepatectomy. Contrast-enhanced ultrasonographic enhancement patterns and quantitative parameters were recorded. The tumor tissue sections were immunostained with human CD34 monoclonal antibody. The patients were classified into a point-line type group (n=36) and a loop-strip type group (n=44) according to microvessel morphology. The microvascular density (MVD) in the different types of microvessels was calculated. The relationship between enhancement patterns of HCC lesions and morphological characteristics of tumor microvessels was analyzed. RESULTS:TS: The mean MVD in HCC was 22.4 +/- 3.5 per 0.2 mm(2) in the point-line group, and 19.6 +/- 6.7 per 0.2 mm(2) in the loop-strip group, and there was no significant difference between them (t=0.948, P=0.354). In the portal vein phase, hypoenhancement was significantly more frequent in HCC (chi(2)=4.789, P=0.029) in the loop-strip group (40/44, 90.9%) than in the point-line group (26/36, 72.2%). The time to hypoenhancement in the loop-strip group (mean 64.84 +/- 26.16 seconds) was shorter than that in the point-line group (mean 78.39 +/- 28.72 seconds) (t=2.247, P=0.022). The time to hypoenhancement was correlated with MVD in the loop-strip group (r=-0.648, P=0.001). CONCLUSIONS: The enhancement patterns on CEUS are related to tumor microvascular morphology, and the type of microvascular morphology influences CEUS characterization. CEUS, an important noninvasive imaging technique, is used to evaluate microvascular morphology and angiogenesis, providing valuable information for antiangiogenic therapy in HCC. (Hepatobiliary Pancreat Dis Jut 2010; 9:605-

关键词： hepatocellular carcinoma contrast-enhanced ultrasonography microvessel morphology

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Modeling studies on divorced eutectic formation of high pressure die cast magnesium alloy

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China Foundry 2018年第1期15卷 58-65页

作者： Meng-wu wu Lin Hua shou-mei Xiong Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of Technology Wuhan 430070 China Hubei Collaborative Innovation Center for Automotive Components Technology Wuhan 430070 China School of Materials Science and Engineering Tsinghua University Beijing 100084 China

The morphology and content of the divorced eutectic in the microstructure of high pressure die casting(HPDC) magnesium alloy have a great influence on the final performance of castings. Based on the previous work concerning simulation of the nucleation and dendritic growth of primary α-Mg during the solidification of magnesium alloy under HPDC process, an extension was made to the formerly established CA(Cellular Automaton) model with the purpose of modeling the nucleation and growth of Mg-Al eutectic. With a temperature field and solute field obtained during simulation of the primary α-Mg dendrites as the initial condition of the modified CA model, modeling of the Mg-Al eutectic with a divorced morphology was achieved. Moreover, the simulated results were in accordance with the experimental ones regarding the distribution and content of the divorced eutectic. Taking a "cover-plate" die casting with AM60 magnesium alloy as an example, the rapid solidification with a high cooling rate at the surface layer of the casting led to a fine and uniform grain size of primary α-Mg, while the divorced eutectic at the grain boundary revealed a more dispersed and granular morphology. Islands of divorced eutectic were observed at the central region of the casting, due to the existence of ESCs(Externally Solidified Crystals) which contributed to a coarse and non-uniform grain size of primary α-Mg. The volume percentage of the eutectic β-Mg_(17)Al_(12) phase is about 2%-6% in the die casting as a whole. The numerical model established in this study is of great significance to the study of the divorced eutectic in the microstructure of die cast magnesium alloy.

关键词： magnesium alloy high pressure die casting divorced eutectic microstructure simulation

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Robust control for an unmanned helicopter with constrained flapping dynamics

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Chinese Journal of Aeronautics 2018年第11期31卷 2136-2148页

作者： rong LI Mou CHEN Qingxian wu College of Automation Engineering Nanjing University of Aeronautics and Astronautics

In this paper, a neural network based adaptive prescribed performance control scheme is proposed for the altitude and attitude tracking system of the unmanned helicopter in the presence of state and output constraints. For handling the state constraints, the barrier Lyapunov function and the saturation function are employed. And, the prescribed performance method is used to deal with the flapping angle constraints for the unmanned helicopter. It is proved that the proposed control approach can ensure that all the signals of the resulting closed-loop system are bounded, and the tracking errors are within the prescribed performance bounds for all time. The numerical simulation is given to illustrate the performance of the proposed scheme.

关键词： Altitude control Attitude control Barrier Lyapunov function Control constraint Prescribed performance Unmanned helicopter

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LINEAR REGRESSION OF INTERVAL-VALUED DATA BASED ON COMPLETE INFORMATION IN HYPERCUBES

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Journal of Systems Science and Systems Engineering 2012年第4期21卷 422-442页

作者： Huiwen WANG rong GUAN Junjie wu Beijing Key Laboratory of Emergency Support Simulation Technologies for City Operations School of Economics and ManagementBeihang University

Recent years have witnessed an increasing interest in interval-valued data analysis. As one of the core topics, linear regression attracts particular attention. It attempts to model the relationship between one or more explanatory variables and a response variable by fitting a linear equation to the interval-valued observations. Despite of the well-known methods such as CM, CRM and CCRM proposed in the literature, further study is still needed to build a regression model that can capture the complete information in interval-valued observations. To this end, in this paper, we propose the novel Complete Information Method （CIM） for linear regression modeling. By dividing hypercubes into informative grid data, CIM defines the inner product of interval-valued variables, and transforms the regression modeling into the computation of some inner products. Experiments on both the synthetic and real-world data sets demonstrate the merits of CIM in modeling interval-valued data, and avoiding the mathematical incoherence introduced by CM and CRM.

关键词： Interval-valued data linear regression complete information method (CIM) hypercubes

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Modeling and Analysis of a Micromotor with an Electrostatically Levitated Rotor

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 1-8页

作者： HAN Fengtian wu Qiuping ZHANG rong Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 China

The modeling and evaluation of a prototype rotary micromotor where the annular rotor is supported electrostatically in five degrees of freedom is presented in order to study the behavior of this levitated micromotor and further optimize the device geometry. The analytical torque model is obtained based on the principle of a planar variable-capacitance electrostatic motor while the viscous damping caused by air film between the stator and rotor is derived using laminar Couette flow model. Simulation results of the closed-loop drive motor, based on the developed dynamic model after eliminating mechanical friction torque via electrostatic suspension, are presented. The effects of the high-voltage drive, required for rotation of the rotor, on overload capacity and suspension stiffness of the electrostatic bearing system are also analytically evaluated in an effort to determine allowable drive voltage and attainable rotor speed in operation. The analytical results show that maximum speed of the micromotor is limited mainly by viscous drag torque and stiffness of the bearing system. Therefore, it is expected to operate the device in vacuum so as to increase the rotor speed significantly, especially for those electrostatically levitated micromotors to be used as an angular rate micro-gyroscope.

关键词： electrostatic levitation electrostatic micromotor variable-capacitance motor micro-gyroscope

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Neutrophil-to-lymphocyte ratio or platelet-to-lymphocyte ratio is a predictive factor of pancreatic cancer patients with type 2 diabetes

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Hepatobiliary & Pancreatic Diseases International 2022年第2期21卷 202-204页

作者： Bao Dong rong-rong wu The First Affiliated Hospital of USTC Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230031China

To the Editor:Pancreatic cancer (PC) is one of the most deadly cancers due to the difficulty of its early *** patients have developed an unresectable PC when diagnosed [1].According to GLOBOCAN2018 estimates,PC ranked the 11th most common cancer in the world counting 458 918 new cases and causing 432 242 deaths(4.5%of all deaths caused by cancer) in 2018 [2].

关键词： patients cancer diabetes

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The Effect of AGN and SNe Feedback on Star Formation,Reionization and the Near Infrared Background

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Chinese Journal of Astronomy and Astrophysics 2008年第6期8卷 631-642页

作者： Lei Wangt Ji-rong Mao shou-Ping Xiang Ye-Fei Yuan Center for Astrophysics University of Science and Technology of China Hefei 230026 China Yunnan Observatory National Astronomical Observatories Chinese Academy of Sciences Kunming 650011 China

Feedback from supernovae （SNe） and from active galactic nuclei （AGN） accom- panies the history of star formation and galaxy evolution. We present an analytic model to explain how and when the SNe and AGN exert their feedback effects on the star formation and galaxy evolution processes. By using SNe and AGN kinetic feedback mechanisms based on the Lambda Cold Dark Matter （LCDM） model, we explore how these feedback mecha- nisms affect the star formation history （SFH）, the Near-Infrared Background （NIRB） flux and the cosmological reionization. We find the values of the feedback strengths, εAGN = 1.0 -0.03^＋0.5 and εSN = 0.04 -0.02^＋0.02, can provide a reasonable explanation of most of the observational resuits, and that the AGN feedback effect on star formation history is quite different from the SNe feedback at high redshifts. Our conclusions manifest quantitatively that these feedback effects decrease star formation rate density （SFRD） and the NIRB flux （in 1.4 - 4.0 μm）, and postpone the time of completion of the cosmological reionization.

关键词： cosmology theory galaxies evolution infrared general stars formation

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