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Effects of Nitrogen Concentration on Microstructure and Antibacterial Property of Copper-Bearing Austenite Stainless Steels

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Journal of Materials Science & Technology 2008年第5期24卷 781-786页

作者： Zhixia ZHANG Laizhu JIANG gang lin Zhou XU School of Material Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China[~echnology Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Technology Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

Austenite antibacterial stainless steels have been found to have wide applications in hospitals and food industries. In recent years epsilon copper precipitation in antibacterial stainless steels has obtained much research interest due to its antibacterial action. The objective of this study was to determine the effects of nitrogen concentration on the precipitation of epsilon copper and antibacterial property. Two kinds of austenite antibacterial stainless steels containing copper and different nitrogen concentration （0.02 and 0.08 wt pct, respectively） were prepared and the microstructures were characterized by a combination of electron microscopy and thermodynamic analysis. A mathematical expression was deduced to predict the effect of nitrogen concentration on the activity coefficient of copper, In（fCu/f^0cu）=0.53524＋4.11xN-0.48x^2N. Higher nitrogen was found to increase the free energy difference of copper concentration distribution between precipitation phase and austenite matrix, stimulate the aggregation of copper atoms from austenite, increase the precipitation amount and consequently enhance the antibacterial property of steel.

关键词： Austenite antibacterial stainless steels Epsilon copper precipitation Nitrogen concentration Thermodynamics analysis Antibacterial property

Simulation of proton–neutron collisions in inverse kinematics and its possible application

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Nuclear Science and Techniques 2021年第4期32卷 60-69页

作者： Bi-Lu Li gang-lin Yu Shi-Fei Shen Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Neutrons have played a vital role in many nuclear physics *** some cases,the inverse kinematics of neutrons colliding with other nuclei are also worth *** this study,the inverse kinematics of thermal neutrons colliding with high-energy protons is simulated by using the Monte Carlo *** neutrons are taken as target particles,whereas protons are incident *** simulation implies that,after collision,the energy of the output neutron at 0°equals the energy of the incident proton.A possible application of the result is proposed that might yield single-energy *** key parameters of the conceptual design were evaluated,demonstrating that the design may reach high-neutron-energy resolution.

关键词： Inverse kinematics Mono-energetic neutron Proton Monte Carlo

Numerical Simulation of Flow in Centrifugal Pump with Complex Impeller

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Journal of Thermal Science 2011年第1期20卷 47-52页

作者： Bao-ling Cui Yong-gang lin Ying-zi Jin The Laboratory of Fluid Transmission and Application Zhejiang Sci-Tech University Hangzhou 310018China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Based on the Navier-Stokes equations and the Spalart-Allmaras turbulence model,three dimensional turbulent flow fields in centrifugal pump with long-mid-short blade complex impeller are calculated and analyzed *** relative velocity and pressure distributions in the flowpart are *** is found that the flow in the passage of the complex impeller is unsymmetrical due to the joint action between volute and *** back-flow region is at inlet of long-blade suction side,near middle part of long-blade pressure side and outlet of short-blade suction *** flow near volute throat is affected greatly by *** relative velocity is large and it is easy to bring back flow at outlet of the complex impeller near volute *** static and total pressure rise uniformly from inlet to outlet in the *** impeller outlet,the pressure periodically decreases from pressure side to suction side,and then the static pressure sharply rise near the *** experimental results show that the back flow in the impeller has an important influence on the performance of pump.

关键词： Complex impeller Centrifugal pump Numerical simulation Experiment

Synthesis of Tetracycline Analogues and Test of Their Affinity on Synthetic Hydroxyapatite

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Chinese Chemical Letters 2002年第1期13卷 13-16页

作者： ling ling WENG gang lin Hu ZHENG School of Pharamacy West China University of Medical SciencesChengdu 610041

Eight of new 5-oxo-[1]benzopyrano[2,3-b]pyridines as the analogues of tetracycline, were designed and synthesized, and their affinity to the hydroxyapatite the inorganic composition of bone were tested.

关键词： Tetracycline affinity hydroxyapatite benzopyran-4-one.

Inorganic nitrogen removal of toilet wastewater with an airlift external circulation membrane bioreactor

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Journal of Environmental Sciences 2007年第1期19卷 12-17页

作者： LI gang WU lin-lin DONG Chun-song WU Guang-xia FAN Yao-bo Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Removal of inorganic nitrogen （inorganic-N） from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor （AEC-MBR） was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19-0.40 kg inorganic-N/（m^3·d） helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen （DO） on inorganic-N removal were examined. Under the condition of MLSS at 1.56-2.35 g/L, BODs/ammonia nitrogen （NH4＋-N） at 1.0, pH at 7.0-7.5, and DO at 1.0-2.0 mg/L, the removal efficiencies of NH4^＋-N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5-1.5 RMB yuan/m^3, and the energy consumption was approximately 0.72 kWh/m^3 at the flux of 8 L/（m^2-h）.

关键词： inorganic nitrogen removal treatment of wastewater from toilet airlift external circulation membrane bioreaetor (AECMBR) membrane bioreactor (MBR)

Tidal current turbine based on hydraulic transmission system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 511-518页

作者： Hong-wei LIU Wei LI Yong-gang lin Shun MA State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Tidal current turbines(TCTs) are newly developed electricity generating *** at the stabilization of the power output of TCTs,this paper introduces the hydraulic transmission technologies into *** hydrodynamics of the turbine was analyzed at first and its power output characteristics were predicted.A hydraulic power transmission system and a hydraulic pitch-controlled system were *** related simulations were ***,a TCT prototype was manufactured and tested in the *** test results have confirmed the correctness of the current design and availability of installation of the hydraulic system in TCTs.

关键词： Tidal current turbines(TCTs) Hydraulic power transmission Hydraulic pitch-controlled system Workshop test

Effect of soil set-up on the capacity of jacked concrete pipe piles in mixed soils

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 637-644页

作者： Jun-wei LIU Zhong-miao ZHANG Feng YU Cun-gang lin MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering Institute of Geoteehnical Engineering Zhejiang University Hangzhou 310058 China

The increase in capacity of displacement piles with time after installation is typically known as soil/pile set-up. A full-scale field test is carried out to observe the set-up effect for open-ended concrete pipe piles jacked into mixed soils. Both the total capacity and the average unit shaft resistance increase approximately linearly with logarithmic time. The average increase rate for unit shaft resistance is 44% per log cycle, while the average increase for total capacity is approximately 21%. A review on case histories for long-term set-up indicates an average set-up rate of approximately 40%. Based on this, the mechanism of pile set-up is discussed in detail and a three-phase model is suggested.

关键词： Concrete pipe pile Jack piling Set-up Pile capacity

Lumped parameter model for resonant frequency estimation of a thermoacoustic engine with gas-liquid coupling oscillation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第3期12卷 232-237页

作者： Ke TANG Tian LEI Xiao-gang lin Tao JIN Yu ZHANG Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Gas-liquid coupling oscillation is a novel approach to reducing the resonant frequency and to elevating the pressure amplitude of a thermoacoustic *** a thermoacoustic engine is used to drive low-frequency pulse tube refrigerators,the frequency matching between the thermoacoustic engine and the refrigerator plays an important *** on an acoustic-electric analogy,a lumped parameter model is proposed to estimate the resonant frequency of a standing-wave thermoacoustic engine with gas-liquid coupling ***,a simplified lumped parameter model is also developed to reduce the computation *** resonant frequency dependence on the mean pressure,the gas space volume,and the water column length is computed and *** impact of different working gases on the resonant frequency is also *** effectiveness of the models is validated by comparing the computed results with the experimental data of the gas-liquid coupling oscillation *** increase in the mean working pressure can lead to a rise in the resonant frequency,and a lower resonant frequency can be achieved by elongating the liquid *** comparison with nitrogen and argon,carbon dioxide can realize a lower frequency due to a smaller specific heat ratio.

关键词： Thermoacoustic engine Gas-liquid coupling oscillation Acoustic-electric analogy Resonant frequency

Different copper sources and levels affect growth performance,copper content,carcass characteristics,intestinal microorganism and metabolism of finishing pigs

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Animal Nutrition 2022年第1期8卷 321-330页

作者： Yang Wen Runxian Li Xiangshu Piao gang lin Pingli He State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Institute of Quality Standards and Testing Technology for Agricultural Products Chinese Academy of Agricultural ScienceKey Laboratory of Agrifood Safety and QualityMinistry of AgricultureBeijing 100081China

Copper(Cu)is an essential trace element in the production of *** study was conducted to investigate the effect of 3 different sources of Cu on growth performance,Cu metabolism,and intestinal microorganisms of finishing pigs,so as to estimate the bioavailability of the 3 sources for pigs.A total of 42 male finishing pigs(88.74±5.74 kg)were randomly allocated to 7 *** factors were 3 sources(CuSO4,Cu-glycine,Cu-proteinate)and 2 levels(5 and 20 mg/kg)of Cu,plus one negative control treatment(0 mg/kg added Cu level)for the entire 28-d *** average daily gain(ADG)and feed to gain ratio(F:G)both increased when Cu was *** Cu level in liver,bile,kidney,serum,lung,urine and feces rose(P<0.001)with increasing dietary Cu level regardless of the ***,pigs receiving organic Cu(glycinate or proteinate)retained more Cu and excreted less Cu than those receiving inorganic Cu(CuSO4),which showed that organic forms were more *** the transcriptional level,changes in the level and source of dietary Cu resulted in modulation of *** the jejunal mucosa,import transporter high affinity copper uptake protein 1(CTR1)and export transporter ATPase copper transporting alpha(ATP7A)in supplemental Cu treatments were down-regulated compared to the ***,peptide transporter 1(PepT1)and lanine-serine-cysteine transporter,type-2(ASCT2)were significantly(P<0.01)up-regulated in 20 mg/kg Cu-proteinate and Cu-glycinate treatments,*** diversity was lowest in the 20 mg/kg CuSO4 treatment,and the ratio of Firmicutes to Bacteroidetes was higher in added Cu treatments,especially Cu-glycinate *** results indicate that uptake of different Cu forms is facilitated by different transporters and transport mechanisms,and compared with inorganic Cu,organic Cu provides benefits to intestinal microflora and reduces Cu excretion.

关键词： Copper Metabolism Residues Microflora community Finishing pig