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Longshore Currents over Barred Beach with Mild Slope

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China Ocean Engineering 2016年第2期30卷 193-204页

作者：王彦邹志利 state Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

The laboratory experiment and numerical simulations of wave-driven longshore currents by random waves on barred beaches with slopes of 1：100 and 1：40 were conducted to investigate the bimodal feature of mean longshore currents,with emphasis on the location and ratio of two peaks of longshore *** location and ratio of two peaks are controlled by the sand *** influences of wave heights and beach slopes on the longshore currents are *** simulations were also performed to compute the measured velocity profile,with the emphasis on the effect of lateral mixing,bottom friction and surface rollers on numerical results.

关键词： barred beach bimodal feature second peak modeling

A Piston-Type Active Absorbing Wavemaker System with Delay Compensation

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China Ocean Engineering 2015年第6期29卷 917-924页

作者：杨洪齐李木国柳淑学张群王静 state Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

Physical model tests with highly reflective structures often encounter a problem of multiple reflections between the structures and the wavemaker. This paper presents a piston-type active absorbing wavemaker system which can absorb most of the reflections. Based on the first-order wavemaker theory, a frequency domain absorption transfer function is modeled. Its time realization can be achieved by designing an IIR digital filter, which is used to control the absorbing wavemaker system. In a real system, time delays often exist in the wave making process. Thus a delay compensation term to the transfer function is proposed. Experimental results show that the system performs well for both regular and irregular waves with periods from 0.6 s to 2.0 s, and the absorption capability is larger than 96.5% at target wave fields.

关键词： wavemaker active absorption IIR digital filter time delay

CeO_2-supported vanadium oxide catalysts for soot oxidation:the roles of molecular structure and nanometer effect

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Journal of Rare Earths 2010年第2期28卷 198-204页

作者：刘坚赵震徐春明段爱军姜桂元 state Key Laboratory of Heavy Oil Processing China University of Petroleum

The nanometer CeO2 powder was prepared by the method of microwave-assisted heating hydrolysis,and the nanometer CeO2-supported or ordinary CeO2-supported vanadia catalysts with different vanadium loadings(atomic ratios:100V/Ce=0.1,1,4,10,and 20) were prepared by an incipient-wetness impregnation *** techniques(XRD,FT-IR,Raman and UV-Vis DRS) were utilized to characterize the structures of VOx/CeO2 *** results showed that the structures of CeO2-supported vanadium oxide catalysts de...

关键词： vanadium oxide catalyst CeO2 nanometer soot combustion rare earths

Carbothermic reduction behaviors of Ti–Nb-bearing Fe concentrate from Bayan Obo ore in China

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International Journal of Minerals,Metallurgy and Materials 2018年第1期25卷 28-36页

作者： Guang Wang Ya-xing Du Jing-song Wang Qing-guo Xue state Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

To support the development of technology to utilize low-grade Ti-Nb-bearing Fe concentrate, the reduction of the concentrate by coal was systematically investigated in the present paper. A liquid phase formed when the Ti Nb-bearing Fe concentrate/coal composite pel- let was reduced at temperatures greater than 1100℃. The addition of CaCO3 improved the reduction rate when the slag basicity was less than 1.0 and inhibited the formation of the liquid phase. Mechanical milling obviously increased the metallization degree compared with that of the standard pellet when reduced under the same conditions. Evolution of the mineral phase composition and microstructure of the reduced Ti-Nb-bearing Fe concentrate/coal composite pellet at 1100~C were analyzed by X-ray diffraction and scanning electron microsco- py-energy-dispersive spectroscopy. The volume shrinkage value of the reduced Ti-Nb-bearing Fe concentrate/coal composite pellet with a basicity of 1.0 was approximately 35.2% when the pellet was reduced at 1100℃ for 20 min, which enhanced the external heat transfer to the lower layers when reduced in a practical rotary hearth furnace. The present work provides key parameters and mechanism understanding for the development of carbothermic reduction technology of a Ti-Nb-bearing Fe concentrate incorporated in a pyrometallurgical utilization flow sheet.

关键词： Ti-Nb bearing iron concentrate carbothermic reduction basicity mechanical milling volume shrinkage

Dynamic Analysis of A 5-MW Tripod Offshore Wind Turbine by Considering Fluid–Structure Interaction

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China Ocean Engineering 2017年第5期31卷 559-566页

作者： ZHANG Li-wei LI Xin state Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

Fixed offshore wind turbines usually have large underwater supporting structures. The fluid influences the dynamic characteristics of the structure system. The dynamic model of a 5-MW tripod offshore wind turbine considering the pile-soil system and fluid structure interaction （FSI） is established, and the structural modes in air and in water are obtained by use of ANSYS. By comparing low-order natural frequencies and mode shapes, the influence of sea water on the free vibration characteristics of offshore wind turbine is analyzed. On basis of the above work, seismic responses under excitation by E1-Centro waves are calculated by the time-history analysis method. The results reveal that the dynamic responses such as the lateral displacement of the foundation and the section bending moment of the tubular piles increase substantially under the influence of the added-mass and hydrodynamic pressure of sea water. The method and conclusions presented in this paper can provide a theoretical reference for structure design and analysis of offshore wind turbines fixed in deep seawater.

关键词： 5-MW tripod offshore wind turbine fluid-structure interaction natural frequency seismic analysis,hydrodynamic pressure

Asymmetric and symmetric meta-correlations in financial markets

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Chinese Physics B 2016年第10期25卷 579-586页

作者：李晓辉沈翔瀛黄吉平 Department of Physics and state Key Laboratory of Surface Physics Fudan University

In financial markets, the relation between fluctuations of stock prices and trading behaviors is complex. It is intriguing to quantify this kind of meta-correlation between market fluctuations and the synchronous behaviors. We refine the theoretical index leverage model proposed by Reigneron et al., to exactly quantify the meta-correlation under various levels of price fluctuations [Reigneron P A, Allez R and Bouchaud J P 2011 Physica A 390 3026]. The characteristics of meta-correlations in times of market losses, are found to be significantly different in Chinese and American financial markets. In addition,unlike the asymmetric results at the daily scale, the correlation behaviors are found to be symmetric at the high-frequency scale.

关键词： financial market collective behavior complex system asymmetry and symmetry

Exhumation and Preservation of the Yangchuling Porphyry W-Mo Deposit in the Jiangnan Tungsten Ore Belt,South China:Insights from(U-Th)/He and Fission Track Dating

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Journal of Earth Science 2025年第1期36卷 46-56页

作者： Yue Sun Ying Wang Jianzhang Pang Samuel C.Boone Minting Wu Chongjian Shao Wei Liu Jiangxi Provincial Key Laboratory of Genesis and Prospect for Strategic Minerals School of Earth ScienceEast China University of TechnologyNanchang330013China Institute of Geology China Earthquake Administration Beijing100029China School of Geography Earth and Atmospheric Sciences The University of MelbourneMelbourneVIC3010Australia Department of Earth Sciences The University of AdelaideAdelaideSA5005Australia Jiangxi DuChang JinDing Tungsten CO. Ltd.Jiujiang332611China

The Yangchuling porphyry W-Mo deposit(YPWD),located in the Jiangnan porphyryskarn tungsten ore belt,is one of the most important and large-scale porphyry W-Mo deposits in South *** previous zircon U-Pb and molybdenite Re-Os data suggest that Yangchuling WMo ore bodies formed almost simultaneously with granodiorite and monzogranitic porphyry at~150–144 Ma,their post emplacement history remains poorly understood,making their preservation status at depth *** this paper,new zircon and apatite(U-Th)/He and apatite fission track(ZHe,AHe and AFT,respectively)data of one hornfels and five intrusive rocks from a 1000-meter borehole are ***,together with new inverse thermal history models and previous geochronological data,help elucidate the post-diagenetic exhumation history and preservation status of the Yangchuling porphyry W-Mo *** general,ZHe and AHe ages decrease gradually from the near surface downwards and have relatively little intra-sample variation,ranging from 133 to 73Ma and 67 to 25 Ma,*** four granodiorites yield similar AFT ages that range from 63 to 55 Ma with mean track lengths varying from 12.2±0.7 to 12.6±0.5μ*** history modelling indicates that the Yangchuling ore district experienced slow,monotonic cooling since the ***-depth relationships are interpreted as recording~3.7±0.8 km of Cretaceous-recent exhumation in response to regional extension throughout South China thought to have been driven by subduction retreat of the Paleo-Pacific *** of estimated net exhumation and previous metallogenic depth of~4–5 km suggests that W-Mo ore bodies could still exist at depths of up to~1.3±0.8 km relative to Earth surface in the YPWD *** of the YPWD is attributed to the limited amount of regional denudation during the Late Cretaceous and Cenozoic.

关键词： (U-Th)/He fission track ore preservation thermochronology Yangchuling porphyry W-Mo deposit

Preparation of active carbons from corn stalk for butanol vapor adsorption

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Journal of Energy Chemistry 2017年第1期26卷 35-41页

作者： Yuhe Cao Keliang Wang Xiaomin Wang Zhengrong Gu Tyler Ambrico William Gibbons Qihua Fan Al-Ahsan Talukder Agricultural and Biosystems Engineering Department South Dakota State UniversityBrookingsSDUSA Department of Physics and Astronomy Stony Brook UniversityStony BrookNYUSA Department of Biology and Microbiology South Dakota State UniversityBrookingsSDUSA Electrical Engineering and Computer Science Department South Dakota State UniversityUSA

Active carbons(ACs) were prepared through chemical activation of biochar from whole corn stalk(WCS)and corn stalk pith(CSP) at varying temperatures using potassium hydroxide as the activating agent. ACs were characterized via pore structural analysis and scanning electron microscopy(SEM). These adsorbents were then assessed for their adsorption capacity for butanol vapor. It was found that WCS activated at900 °C for 1 h(WCS-900) had optimal butanol adsorption characteristics. The BET surface area and total pore volume of the WCS-900 were 2330 m2/g and 1.29 cm3/g, respectively. The dynamic adsorption capacity of butanol vapor was 410.0 mg/g, a 185.1% increase compared to charcoal-based commercial AC(143.8 mg/g).

关键词： Corn stalk KOH Active carbon Gas stripping Butanol adsorption

The gut microbiome: an orchestrator of xenobiotic metabolism

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Acta Pharmaceutica Sinica B 2020年第1期10卷 19-32页

作者： Stephanie L.Collins Andrew D.Patterson Department of Biochemistry Microbiologyand Molecular Biologythe Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Veterinary and Biomedical Science the Pennsylvania State UniversityUniversity ParkPA 16802USA

Microbes inhabiting the intestinal tract of humans represent a site for xenobiotic *** gut microbiome,the collection of microorganisms in the gastrointestinal tract,can alter the metabolic outcome of pharmaceuticals,environmental toxicants,and heavy metals,thereby changing their *** chemical modification of xenobiotics by the gut microbiome,either through the intestinal tract or re-entering the gut via enterohepatic circulation,can lead to increased metabolism or bioactivation,depending on the enzymatic activity within the microbial *** enzymes encoded within the microbiome include those that reverse the modifications imparted by host detoxification ***,the microbiome can limit xenobiotic absorption in the small intestine by increasing the expression of cell-cell adhesion proteins,supporting the protective mucosal layer,and/or directly sequestering ***,host gene expression is regulated by the microbiome,including CYP450s,multi-drug resistance proteins,and the transcription factors that regulate *** the microbiome affects the host and pharmacokinetics of the xenobiotic,xenobiotics can also influence the viability and metabolism of the *** understanding of the complex interconnectedness between host,microbiome,and metabolism will advance with new modeling systems,technology development and refinement,and mechanistic studies focused on the contribution of human and microbial metabolism.

关键词： Gut microbiome Xenobiotic metabolism Absorption Gastrointestinal tract Pharmacokinetics Enterohepatic circulation Bioactivation