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Journal of Environmental Sciences 2013年第7期25卷 1492-1499页

作者： Dina Tan Honghu Zeng Jie Liu Xiaozhang Yu Yanpeng Liang Lanjing Lu College of Environmental Science and Engineering Guilin University of Technology Guangxi institute of Building research & design Guangxi Polytechnic of Construction

The kinetics of thedegradation of trace nitrobenzene （NB） by a granular activated carbon （GAC） enhanced microwave （MW）/hydrogen peroxide （H202 ） systemwas studied. Effects of pH, NB initial concentration and tert-butyl alcohol on the removal efficiencywere examined. Itwas found that the reaction rate fitswell to first-order reaction kinetics in the MW/GAC/H202 process. Moreover, GAC greatly enhanced thedegradation rate of NB inwater. Under a given condition （MW power300 W, H202dosage 10 mg/L, pH 6.85 and temperature （60 ± 5）°C）, thedegradation rate of NBwas 0.05214 min 1when4 g/L GACwas added. In general, alkaline pHwas better for NBdegradation; however, the optimum pHwas 8.0 in the tested pH value range of4.0-12.0. At H202dosage of 10 mg/L and GACdosage of4 g/L, the removal of NBwasdecreasedwith increasing initial concentrations of NB, indicating that a low initial concentrationwas beneficial for thedegradation of NB. These results indicated that the MW/GAC/H202 processwas effective for trace NBdegradation inwater. Gas chromatography-mass spectrometry analysis indicated that a hydroxyl radical addition reaction anddehydrogenation reaction enhanced NBdegradation.

关键词： microwave granular activated carbon hydrogen peroxide nitrobenzene hydroxyl radicals

Parametric study of turbine NGV blade lean and vortex design

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Chinese Journal of Aeronautics 2016年第1期29卷 104-116页

作者： Zhang Shaowen David G.Mac Manus Luo Jianqiao Department of Turbine design China Aviation Powerplant Research Institute AVIC School of Aerospace Transport and Manufacturing Cranfield University

The effects of blade lean and vortex design on the aerodynamics of a turbine entry nozzle guide vane （NGV） are considered using computational fluid dynamics. The aim of the work is to address some of the uncertainties which have arisen from previous studies where conflicting results have been reported for the effect on the NGV. The configuration was initially based on the energy efficient engine turbine which also served as the validation case for the computational method. A total of 17 NGV configurations were evaluated to study the effects of lean and vortex design on row efficiency and secondary kinetic energy. The distribution of mass flow ratio is introduced as an additional factor in the assessment of blade lean effects. The results show that in the turbine entry NGV, the secondary flow strength is not a dominant factor that determines NGV losses and therefore the changes of loading distribution due to blade lean and the associated loss mecha- nisms should be regarded as a key factor. Radial mass flow redistribution under different NGV lean and twist is demonstrated as an addition key factor influencin~ row efficiency.

关键词： Blade lean Losses Mass flow radial distribu-tion Parametric study Secondary kinetic energy Turbine Vortex design

Numerical simulations of FPSO with sloshing tanks in a random freak waves

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Journal of Hydrodynamics 2022年第3期34卷 491-498页

作者： Yuan Zhuang Guo Wang De-cheng Wan Jian-wei Wu Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Marine design and research institute of China Shanghai200011China Wuhan Second Ship design and research institute Wuhan430205China

This paper presents a potential-viscous coupled method to simulate a floating production storage and offloading(FPSO)with two liquefied natural gas(LNG)sloshing tanks in a random freak *** potential theory uses high-order-spectral(HOS)*** random wave is generated by HOS for 2000 s,and a freak wave is observed around 1830 *** FPSO LNG model was firstly verified in regular waves using HOS-computational fluid dynamics(CFD)coupled method and validated the HOS-CFD coupled method can solve the ship motion coupled with sloshing tanks *** FPSO with LNG tanks are then simulated in the freak wave,showed the coupling effects when the freak wave *** the existence of the sloshing tanks,the amplitude of the roll motion decreases and the period of roll motion *** breaking phenomenon can be observed when the wave crest of the freak wave encounters with the ship.

关键词： Ship motion with sloshing tank high-order-spectral-computational fluid dynamics(HOS-CFD)method naoe-FOAM-SJTU solver freak waves

Numerical investigations of focused wave interact with a moving cylinder

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Journal of Hydrodynamics 2023年第4期35卷 724-735页

作者： Yuan Zhuang Fu-chang Zhou Wen-jun Zhou De-cheng Wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Wuhan Second Ship design and research institute Wuhan430205China Marine design and research institute of China Shanghai200011China

This paper presents a numerical study on focused wave and current interactions with a *** cylinder is moving in the opposite direction to the wave *** effective computational decomposition method is adopted to reduce the calculation resources.A potential solver high-order spectral(HOS)method is applied to generate focused wave field,while our in-house computational fluid dynamics(CFD)solver naoe-FOAM-SJTU with overset grid takes the charge of achieving the viscous effect around the moving *** viscous domain moving with the cylinder thus the size and mesh grids in computational domain is greatly *** pressure on cylinder surface and wave fields around cylinder are compared with experimental data,shows a well ***,the scattering wave field and vortex shedding are *** the existence of moving cylinder,the classical scattering wave types are still observed.

关键词： Focused wave moving cylinder naoe-FOAM-SJTU solver computational decomposition method

Chemically robust carbon nanotube-PTFE superhydrophobic thin films with enhanced ability of wear resistance

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Progress in Natural Science:Materials International 2017年第3期27卷 396-399页

作者： Kewei Wang Pan Xiong Xiuping Xu Kan Wang YanLong Li Yufeng Zheng State Nuclear Electric Power Planning design & research institute College of Engineering Peking University

A chemically robust superhydrophobic nanocomposite thin film with enhanced wear resistance is prepared from a composite comprising polytetrafluoroethylene（PTFE） and carbon *** superhydrophobic thin films with hierarchical structure are fabricated by spraying an environmentally friendly aqueous dispersion containing carbon nanotubes and PTFE resin on silicon *** films with a contact angle of 154.1°± 2° and a sliding angle less than 2° remain superhydrophobic after abrading over 500 times under a pressure of 50 g/cm;.The thin film is also extremely stable even under much stress *** further the understanding of the enhancement of wear resistance,we investigated the formation of microsized structure and their *** growth of microbumps is caused by attracting solution droplet to the hydrophilic islands on hydrophobic surface.

关键词： Superhydrophobicity Thin film Carbon nanotube Wear resistance

Epithermal Ageing Mechanism of Gussasphalt

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 466-470页

作者：郝增恒 School of Traffic Science and Engineering Harbin Institute of Technology Chongqing Communications research and design Instituts

The normal asphalt index test, DSR test, FTIR and the GPC distribution analysis of molecular weight on the extraction and recovery of asphalt of the gussasphalt, SMA extraction and recovery of asphalt and the rotary-thin-film-oven-aged asphalt above 240 ℃ were introduced. The results indicate the rutting factor and fatigue factor of the extraction and recovery of asphalt of the gussasphalt are greatly improved, and an obvious absorption peak of carbonyl and a further decrease of the SBS molecular weight of the gussasphalt are found.

关键词： gussasphalt epithermal ageing rheolagical performance fourier transforms infrared spectroscopy gel permeation chromatography

Solidification/stabilization of Dewatered Sludge with Multi-Component Solidifying Agents

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Journal of Harbin institute of Technology(New Series) 2013年第6期20卷 46-52页

作者： Jun-Qiu Jiang Kun Wang Zi-Ye Li Yang Li Qing-Liang Zhao Guang-Yi Liu Department of Municipal and Environmental & Engineering Harbin Institute of Technology Southwest Municipal Engineering design & research institute of China

This work experimentally examined the optimal proportioning of sludge curing agent for dewatered sludge curing on solidified sludge,two components sludge curing agent consisted of cement and slag,and three components consisted of cement,slag and inorganic salt. The results showed that,increasing of curing ages could increase unconfined compressive strength and reduce moisture content for solidified sludge. For the test of two components,the biggest unconfined compressive strength of the solidified sludge achieved to 543. 72 kPa and the minimum moisture content achieved to 3. 56% of 21 d. The optimum proportion of the sludge curing agent of two components is sludge: cement: slag = 1 ∶ 0. 05 ∶ 0. 2 which selected by design-expert. It could rapidly increasing the unconfined compressive strength of solidified sludge when added three components sludge curing agent( sludge: cement: slag: MgSO4= 1 ∶ 0. 05 ∶ 0. 2 ∶ 0. 03) on sludge curing. The results showed that,curing ages of 7 d,the unconfined compressive strength could achieve to 126. 74 kPa,which was more than 11 times comparison with the solidified sludge curing by two components curing agent. Two or three components sludge curing agent all could stabilize the heavy metals on solidified sludge and the leaching of heavy metals was below the government standard,while the stability of the heavy metals was superior for three components sludge curing agent.

关键词： dewatered sludge solidification curing agent stabilizationCLC number:X705 Document code:AArticle ID:1005-9113(2013)06-0046-07

Investigation on corrosion of yttrium-doped magnesium-based sacrificial anode in ground grid protection

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Journal of Rare Earths 2010年第S1期28卷 389-392页

作者：冯拉俊闫爱军孟勇强侯娟玲 School of Materials Science and Engineering Xi'an University of Technology Shaanxi Electric Power research institute North Western Electric Power design institute

In the simulated DC and AC discharge circuit in ground grid protection of substation,corrosion and potential of magnesium anode with yttrium addition were studied by potential measurement and scanning electron *** results showed that potential of anode increased with increasing current density in DC simulation,potential increase of anode with 0.1% yttrium addition was the smallest,and the affordable current density of the anode reached 1.85 A/cm2,which was two times that of the anode without yttrium *** AC simulation,addition of yttrium had less effect on its *** of magnesium alloy sacrificial anode without yttrium addition were the equiaxed grains of magnesium grains coated with β-Mg17Al12,while the anode with yttrium was α-Mg phase with dispersed β *** corroded magnesium anode with 0.1% yttrium addition showed the most uniform and the smallest pit on its surface.

关键词： yttrium magnesium anode ground grid rare earths

Effects of Heavy Metal Contamination on Microbial Biomass and Community Structure in Soils

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Chinese Journal Of Geochemistry 2004年第4期23卷 319-328页

作者：杨元根刘丛强徐磊吴攀张国平 institute of Geochemistry Chinese Academy of Sciences Guizhou Academy for Environmental Science research and design

Zinc smelting near Magu Town, Hezhang County, Guizhou Province, resulted in vegetation destruction and the accumulation of heavy metals, to varying extent, in adjacent soils, where up to 162.2- 877.9 mg·kg -1 Zn, 37.24- 305.6 mg·kg -1 Pb, and 0.50- 16.43 mg·kg -1 Cd, were detected. These values greatly exceed the background levels of these elements in soils. The concentrations of heavy metals (particularly Pb, Zn) were positively correlated with the contents of Fe 2O 3 and Al 2O 3 in the soils, showing that Fe and Al oxides play an important role in retaining heavy metals. Chemical fractionation indicates that Pb and Zn were associated mainly with Fe and Mn oxides and minerals, whereas Cd was dominated by exchangeable form. Microbial biomass in the soils was relatively low, in the range of 57.00- 388.0μg C·g -1, and was negatively correlated with heavy metal concentrations in the soils. The correlation coefficient of microbial biomass C to Zn concentrations in the soils was as high as -0.778 (p< 0.01), indicating that the heavy metal contamination has toxic effects on microorganisms in soil. The results of Biolog measurements demonstrated that there were no significant changes in microbial community structure in the heavy metal contaminated soils. Gene fragments were similar to one another after the DNA was extracted from soil microbes and experienced PCR (polymerase chain reaction) and DGGE (denaturing gradient gel electrophoresis) reactions. These results indicated that light heavy-metal pollution may not result in any change in soil microbial community structure.

关键词：重金属污染微生物密度群落结构土壤学

Numerical and experimental evaluation on methods for parameter identification of thermal response tests

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Journal of Central South University 2012年第3期19卷 816-823页

作者：王沣浩冯琛琛颜亮王新轲 Building Energy research Center Xi'an Jiaotong University Shanghai Architectural design&research institute Co. Ltd.

Several parameter identification methods of thermal response test were evaluated through numerical and experimental study.A three-dimensional finite-volume numerical model was established under the assumption that the soil thermal conductivity had been known in the simulation of thermal response *** thermal response curve was firstly obtained through numerical ***,the accuracy of the numerical model was verified with measured data obtained through a thermal response *** on the numerical and experimental thermal response curves,the thermal conductivity of the soil was calculated by different parameter identification *** calculated results were compared with the assumed value and then the accuracy of these methods was ***,the effects of test time,variable data quality,borehole radius,initial ground temperature,and heat injection rate were *** results show that the method based on cylinder-source model has a low precision and the identified thermal conductivity decreases with an increase in borehole *** parameter estimation,the measuring accuracy of the initial temperature of the deep ground soil has greater effect on identified thermal conductivity.

关键词： ground source heat pump thermal response parameter identification method numerical simulation