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Discussion on New Evaluation Technology of Non-Metallic Composite Continuous Pipe for Oil and Gas Field 被引量:1
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作者 Xuehua Cai Xiaodong Shao +3 位作者 Zhao Zhang Han Ding Guoquan Qi Houbu Li 《Journal of Materials Science and Chemical Engineering》 2021年第12期1-6,共6页
<div style="text-align:justify;"> In view of the serious lack and lag of the test and evaluation technology of non-metallic composite continuous pipe, and focusing on the characteristics of the applica... <div style="text-align:justify;"> In view of the serious lack and lag of the test and evaluation technology of non-metallic composite continuous pipe, and focusing on the characteristics of the application of non-metallic composite continuous pipe in oil field, this paper discusses a series of new full-scale test and evaluation technologies for accurately evaluating the product quality and practical application performance of non-metallic composite continuous pipe, which effectively solves the major technical problem that the new products of non-metallic pipe cannot be accurately evaluated. Based on the characteristics of the application of non-metallic composite continuous pipe in oil field, a series of new full-scale test evaluation technologies which can accurately evaluate the product quality and practical application performance of non-metallic pipe are designed through a large number of tests. The test and evaluation technology can accurately evaluate the key performance of high and low pressure cycle, high and low temperature cycle, gas permeability resistance, minimum bending radius etc. It provides a scientific evaluation basis for the standardized application of non-metallic continuous pipe and a reliable quality control method for the selection of products in oil field. </div> 展开更多
关键词 non metallic Composite Continuous pipe Full-Size High and Low Temperature Cycle Minimum Bending Radius
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Flow Electrification of Insulated Liquid in Metal Pipes 被引量:2
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作者 ZHU Shouxin LIU Lin TAKAHASHI Satoshi 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第6期1115-1120,共6页
When relative motion occurs between a liquid and a solid, the two phases carry electric charge with opposite signs. The created charge easily accumulates in the liquid, and the amount of the charge carried in an insul... When relative motion occurs between a liquid and a solid, the two phases carry electric charge with opposite signs. The created charge easily accumulates in the liquid, and the amount of the charge carried in an insulated liquid refers to many factors, such as contact area with the solid surface, the contact time, and so forth. However, current theories agree that the amount of charge created during flow electrification is proportional to the contact surface. In this paper, the classical wall current theory is applied to establish an interfacial electrical double-layer model of flow electrification phenomena when an insulated liquid passes over metal pipe surface. Meanwhile, in conjunction with charge relaxation function, the relation between the charge density and flow velocity, the contact time and the contact area is obtained during the liquid flowing process. The experimental result demonstrates that the flowing charge carried in the insulated liquid is not simply proportional to the contact area, but has a non-linear dependence on the contact area and the contact time. Moreover, down flow experimental equipment pipes of different length and diameter, and dielectric hydraulic oil VG46 are used in an experimental study of laminar flow, in order to understand electrification phenomena in dielectric liquid flowing over metal pipes of different length and aperture. If they both increase linearly, charge relaxation will increase exponentially. As a result, the test result verifies related theoretical analysis, and the method given provides a theoretical basis to analyze interracial electrical phenomena. 展开更多
关键词 flow electrification metal pipes contact time RELAXATION
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Effect of continuous casting speed on mold surface flow and the related near-surface distribution of non-metallic inclusions 被引量:9
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作者 Peng Fei Yi Min +1 位作者 Cheng-jun Liu Mao-fa Jiang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第2期186-193,共8页
For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. Th... For the control of surface defects in interstitial-free(IF) steel, quantitative metallographic analyses of near-surface inclusions and surface liquid flow detection via the nail-board tipping method were conducted. The results show that, at casting speeds of 0.8 and 1.0 m/min, a thin liquid mold flux layer forms and non-uniform floating of argon bubbles occurs, inducing the entrainment and subsequent entrapment of the liquid flux; fine inclusion particles of Al_2O_3 can also aggregate at the solidification front. At higher casting speeds of 1.4 and 1.6 m/min, the liquid mold flux can be entrained and carried deeper into the liquid steel pool because of strong level fluctuations of the liquid steel and the flux. The optimal casting speed is approximately 1.2 m/min, with the most favorable surface flow status and, correspondingly, the lowest number of inclusions near the slab surface. 展开更多
关键词 non-metallic INCLUSIONS DISTRIBUTION CASTING SPEED surface flow
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Study on the separation process of non-metallic inclusions at the steel-slag interface using water modeling 被引量:5
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作者 Ye-lian Zhou Zhi-yin Deng Miao-yong Zhu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第6期627-637,共11页
The separation process of non-metallic inclusions at the steel–slag interface was simulated by physical modeling. Three different kinds of particles (octahedral, plate-like, and spherical) and three different oils (k... The separation process of non-metallic inclusions at the steel–slag interface was simulated by physical modeling. Three different kinds of particles (octahedral, plate-like, and spherical) and three different oils (kerosene, bean oil, and pump oil) were used to model inclusions and slags, respectively. The effects of inclusion geometry (shape and size) and slag properties (viscosity and interfacial tension) on the separation process were investigated. The results revealed that the variation of surface free energy and the viscosity of the slag are two significant factors affecting the separation process of inclusions at the steel–slag interface. The variation of surface free energy helped inclusions enter the slag phase, whereas the decrease of slag viscosity shortened the separation time. The deformation of the steel–slag interface could give rise to the resistance force, which would resist inclusions passing through the interface. A liquid film formed on the inclusion as it passed through the steel–slag interface, which might be related to the inclusion’s shape. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Free energy Interfaces (materials) KEROSENE Liquid films SEPARATION VISCOSITY
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Motion behavior of non-metallic particles under high frequency magnetic field 被引量:1
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作者 张忠涛 郭庆涛 +3 位作者 于凤云 李捷 张剑 李廷举 《中国有色金属学会会刊:英文版》 CSCD 2009年第3期674-680,共7页
Non-metallic particles, especially alumina, are the main inclusions in aluminum and its alloys. Numerical simulation and the corresponding experiments were carried out to study the motion behavior of alumina particles... Non-metallic particles, especially alumina, are the main inclusions in aluminum and its alloys. Numerical simulation and the corresponding experiments were carried out to study the motion behavior of alumina particles in commercial pure aluminum under high frequency magnetic field. At the meantime, multi-pipe experiment was also done to discuss the prospect of continuous elimination of non-metallic particles under high frequency magnetic field. It is shown that: 1) results of numerical simulation are in good agreement with the experimental results, which certificates the rationality of the simulation model; 2) when the intensity of high frequency magnetic field is 0.06 T, the 30 μm alumina particles in melt inner could migrate to the edge and be removed within 2 s; 3) multi-pipe elimination of alumina particles under high frequency magnetic field is also effective and has a good prospect in industrial application. 展开更多
关键词 高频磁场 金属粒子 运动行为 氧化铝颗粒 工业应用前景 数值模拟 金属颗粒 仿真模型
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Study on non-metallic inclusions in Al killed high strength alloy steel refined by high basicity and high Al_2O_3 content slag 被引量:11
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作者 WANG Xinhua,JIANG Min and WANG Wanjun School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China 《Baosteel Technical Research》 CAS 2010年第S1期21-,共1页
Laboratory and industrial studies were carried out to investigate non-metallic inclusions in high strength alloy steel refined by high basicity and high Al_2O_3 slag.It was found that the steel/slag reaction time larg... Laboratory and industrial studies were carried out to investigate non-metallic inclusions in high strength alloy steel refined by high basicity and high Al_2O_3 slag.It was found that the steel/slag reaction time largely affected non-metallic inclusions.With the reaction time increased from 30 min to 90 min in laboratory study,MgO-Al_2O_3 spinels were gradually changed into CaO-MgO-Al_2O_3 system inclusions surrounded by softer CaO-Al_2O_3 surface layers.By using high basicity slag which contained as much as 41%Al_2O_3 in the laboratory study,ratio of low melting temperature CaO-MgO-Al_2O_3 system inclusions was remarkably increased to above 80%.In the industrial experiment,during the secondary refining,the inclusions changed in order of 'Al_2O_3→MgO-Al_2O_3→CaO-MgO-Al_2O_3'.Through the LF and RH refining,most inclusions could be transferred to lower melting temperature CaO-Al_2O_3 and CaO-MgO-Al_2O_3 system inclusions. 展开更多
关键词 non-metallic inclusion SPINEL SLAG high strength alloying steel refining fatigue
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Three-dimensional analysis technology for accurately characterizing non-metallic inclusion particles in steel 被引量:1
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作者 ZHANG Yi CHEN Jinming +2 位作者 MIAO Lede WANG Guodong WU Junfei 《Baosteel Technical Research》 CAS 2011年第4期40-48,共9页
In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis ... In this paper, a kind of three-dimensional analysis technology for characterizing non-metallic inclusions in steel was clearly elaborated. It is an electron microscopy observation, namely the non-aqueous electrolysis extraction method with a settled coulometer. In the research,the extraction effects of non-metallic inclusions in different electrolysis systems were studied, and it was concluded that alkalescent 2% TEA non-aqueous electrolyte was applicable for extracting most of non-metallic inclusion particles in steel. And then, in order to ensure the microscopic characterization and statistical calculation of inclusion particles, some electrolysis parameters should be confirmed, such as the size of the sample, control of the electrolysis mass, electric current, etc. Furthermore, for preventing the disturbance of carbides and presenting clear three-dimensional appearance by microscopic characterization, magnetic separation was utilized to separate the inclusion particles from carbides, which was useful for getting more veracious types, particle sizes and chemical composition of inclusions. Moreover, through calculation of quantity and particle size of inclusions in continuous determinate fields, the total quantity per unit volume or area and the particle size distribution of inclusions could be acquired by conversion with electrolysis loss. Besides, the comparison between this method and traditional quantitative metallography was also discussed, and finally, a conclusion was drawn that both of them have respectively applications in characterizing inclusions. 展开更多
关键词 non-metallic inclusion non-aqueous electrolytic extraction SEM microscopic characterization
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A Novel Uniplanar Multi-Electrode Capacitive Sensor for In-Situ Weathering Damage Detection of Nonmetallic Materials 被引量:1
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作者 Ensheng Dong Yonggui Dong +2 位作者 Wener Lv Huibo Jia Jun Li 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2006年第A03期630-633,共4页
A uniplanar capacitive sensor with 5-electrodes on one plane substrate and a large reflector electrode,was designed to get the corresponding capacitance information for weathering damage detection of non-metallic mate... A uniplanar capacitive sensor with 5-electrodes on one plane substrate and a large reflector electrode,was designed to get the corresponding capacitance information for weathering damage detection of non-metallic materials exposed to a service environment.A 2-D finite-element method was employed to simulate the electric potential distribution and capacitance measurements for the sensor.2 marble slabs,one was healthy and the other was notched,were experimentally detected.Both the simulation and the preliminary experimental results show that the measured capacitances decrease after weathering damage occurs in nonmetallic material.The reflector can enlarge the sensitive depth.The weathering assessment of nonmetallic materials can be done by processing the measured capacitances.The proposed approach can effectively detect the weathering damage of nonmetallic material and can be practically used for in-situ weathering damage evaluation. 展开更多
关键词 capacitive sensor weathering damage detection reflector electrode non-metallic materials
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ANALYTICAL SOLUTION OF FLOW OF SECOND-ORDER NON-NEWTONIAN FLUIDS THROUGH ANNULAR PIPES 被引量:1
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作者 朱文辉 刘慈群 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1993年第3期209-215,共7页
This paper presents an analytical solution to the unsteady flow of the second-order non-Newtonian fluids by the use of intergral transformation method. Based on the numerical results, the effect of non-Newtonian coeff... This paper presents an analytical solution to the unsteady flow of the second-order non-Newtonian fluids by the use of intergral transformation method. Based on the numerical results, the effect of non-Newtonian coefficient Hc and other parameters on the flow are analysed. It is shown that the annular flow has a shorter characteristic time than the general pipe flow while the correspondent velocity, average velocity have a ... nailer value for a given Hc. Else, when radii ratio keeps unchanged, the shear stress of inner wall of annular flow will change with the inner radius -compared with the general pipe flow and is always smaller than that of the outer wall. 展开更多
关键词 integral transformation shape factor non-Newtonian coefficient second-order fluids annular pipes
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Behavior of Non-metallic Inclusions in Centrifugal Induction Electroslag Castings 被引量:1
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作者 Xichun Chen, Jie Fu, Deguang Zhou, Weiguo Xu (Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China) 《Journal of University of Science and Technology Beijing》 CSCD 2001年第2期91-94,共4页
In order to know the behavior of non-metallic inclusions in centrifugal induction electroslag castings (CIESC), non-metallic inclusions in 5CrMnMo and 4Cr5MoSiV1 were qualitatively and quantitatively analyzed. The lar... In order to know the behavior of non-metallic inclusions in centrifugal induction electroslag castings (CIESC), non-metallic inclusions in 5CrMnMo and 4Cr5MoSiV1 were qualitatively and quantitatively analyzed. The largest size of inclusions in the casting and the thermodynamic possibility of TiN precipitation in steel were also calculated. The results show that sulfide inclusions are evenly distributed and the content is low. The amount of oxide inclusions in CIESC: 4Cr5MoSiV1 steel is close to the ESR steel and lower than that in the EAF steel, and there are some differences along radial direction. Nitride inclusions are fine and the diameter of the largest one is 3-1 mum. With the increase of the centrifugal machine's rotational speed, the ratio of round inclusions increases and the ratio of sharp inclusions decreases. According to the experiment and the calculation results, it is pointed out that the largest diameter of non-metallic inclusions in the CIESC 4Cr5MoSiV1 casting is only 6.6 mum, and [N%][Ti%] in 4Cr5MoSiV1 steel should be controlled less than 4.4x 10(-5) in order to further reduce the amount and size of TiN inclusions. 展开更多
关键词 centrifugal induction electroslag casting non-metallic inclusions 4Cr5MoSiV1 steel 5CrMnMo steel TiN precipitation
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Effect of retained austenite and nonmetallic inclusions on the thermal/electrical properties and resistance spot welding nuggets of Si-containing TRIP steels 被引量:1
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作者 V.H.Vargas I.Mejía +1 位作者 V.H.Baltazar-Hernández C.Maldonado 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第1期52-63,共12页
Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical pr... Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, C, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets. 展开更多
关键词 transformation-induced plasticity steel RETAINED austenite non-metallic inclusions magnetic saturation electrical PROPERTIES THERMAL PROPERTIES resistance spot welding NUGGET
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Characterization and analysis of non-metallic inclusions in Ni42-Fe expansive alloy
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作者 沈婕 夏天东 +1 位作者 王晓军 冯晓春 《中国有色金属学会会刊:英文版》 CSCD 2007年第A02期1165-1171,共7页
Cracks and ruptures always occur during wire drawing process of 42% nickel-iron expansive alloy. In order to study the reasons of these phenomena,a method of metallographic observation in combination with sample elect... Cracks and ruptures always occur during wire drawing process of 42% nickel-iron expansive alloy. In order to study the reasons of these phenomena,a method of metallographic observation in combination with sample electrolysis was used to characterize the non-metallic inclusions in the alloy wire. The results indicate that the inclusions in the alloy are oxidation products during the process of melting. There are single or complex phase inclusions composed of elements such as Al,Si,Ca,Ti,Fe,and O2. Among them,the macro-inclusions are TiO2 compound inclusions formed by the adhesion of Al and Si oxides on them. These inclusions are fragile ones with a low strain rate,as well as a rather high hardness,so that they are the main reason that leads to the surface cracks and ruptures in the alloy wires. The analysis has educed that the key point to enhance the product quality is to promote the cleanliness of the melt,control the types and quantity of non-metal inclusions in the alloy. 展开更多
关键词 镍-铁膨胀合金 非金属夹杂物 机械特征 裂纹
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Non-metallic Inclusions in Continuously Cast Aluminum Killed Steels
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作者 Wenjun Wang, Xinhua Wang, Jiongming Zhang, Wanjun Wang, Youyu Zhou ( Metallurgy School, University of Science and Technology Beijing, Beijing 100083, China Steelmaking Research Institute, Wuhan Iron and Steel Group, Wuhan 430080, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2000年第3期193-196,共4页
In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Pro... In aluminum killed steels, the size, shape, quantity and formation of non-metallic inclusions in ladle steel (before and after RH vacuum treatment) and in tundish as well as in slabs were studied by EPMA (Electron Probe Microanalysis) and by analyzing the total oxygen. The results showed that in the slabs the total oxygen was quite low and the inclusions discovered were mainly small-sized angular alumina inclusions. This indicates that most inclusions have been removed by floating out during the continuous casting process. In addition, the countermeasures were discussed to decrease the alumina inclusions in the slabs further. 展开更多
关键词 aluminum killed steel non-metallic inclusion ALUMINA continuous casting
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Studies of non-metallic organic disinfectants on inactivation of avian influenza viruses
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作者 Huaguang Lu 《Health》 2013年第8期1-6,共6页
Six different kinds of non-metallic or organic disinfectants were obtained in this research study including “Neutral Electrolyzed Water”, “M22” organic disinfectant solution, Superoxy Food Wash disinfectant, Hydro... Six different kinds of non-metallic or organic disinfectants were obtained in this research study including “Neutral Electrolyzed Water”, “M22” organic disinfectant solution, Superoxy Food Wash disinfectant, Hydrogen Peroxide, Clorox Germicidal Bleach and Clidox-S. The effectiveness of these disinfectants was studied against various subtypes of avian influenza virus (AIV). The virus-disinfectant mixtures were prepared in serial dilutions of each disinfectant with a constant virus titer and incubated at ambient temperature in different time intervals for virus inactivation. The virus inactivation results were determined by virus recovery in embryonating chicken eggs. Among the six different kinds of nonmetallic disinfectants obtained for this research project, Neutral Electrolyzed Water, “M22” solution, Clorox Germicidal Bleach and Clidox-S were effectively inactivated AIV with appropriate working dilutions and reaction times. Superoxy Food Wash disinfectant and Hydrogen Peroxide were found having limited effect on virus inactivation with extended exposure times of more than 2 hours. These research findings provide scientific data to poultry industry with guidelines to select and use non-metallic organic disinfectants for poultry flock sanitation and disinfection to effectively prevent and control of avian influenza outbreaks. 展开更多
关键词 AVian Influenza Virus non-metallic DISINFECTANTS Neutral Electrolyzed Water M22 ORGANIC DISINFECTANT Superoxy Food WASH Hydrogen Peroxide Clorox Germicidal BLEACH Clidox-S
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Electrocatalytic activity of non-precious metal catalyst Co-N/C toward oxygen reduction reaction 被引量:3
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作者 Yu Jun Si Chang Guo Chen +1 位作者 Wei Yin Hui Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第8期983-986,共4页
Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinumfree electrocatalyst Co-N/C(800) for oxygen reduction reaction(ORR) was synthesized by mixing ... Metallic cobalt was deposited on acetylene black to synthesize a composite Co/C by chemical reduction method.A platinumfree electrocatalyst Co-N/C(800) for oxygen reduction reaction(ORR) was synthesized by mixing the composite Co/C with urea and heat-treating at 800℃.The results from linear sweep voltammograms indicated that the Co-N/C(800) is active to ORR.Theβ-Co and cobalt oxides are not the active site of the catalyst Co-N/C.However,the existence of cobalt facilitated the modification of nitrogen to carbon black and led to the formation of active site of catalyst Co-N/C(800). 展开更多
关键词 Oxygen reduction reaction ELECTROCATALYST non-precious metal Active site
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POLISHING OF NON-FERROUS METALS WITH HIGH EFFICIENCY
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作者 Chen, Yuquan Peng, Guangbin Pei, Yi 《中国有色金属学会会刊:英文版》 EI CSCD 1998年第3期126-129,共4页
1INTRODUCTIONBesidessteels,nonferousmetalssuchasaluminium,copper,titaniumandtheiraloysareveryimportantmate... 1INTRODUCTIONBesidessteels,nonferousmetalssuchasaluminium,copper,titaniumandtheiraloysareveryimportantmaterials,duetotheira... 展开更多
关键词 non FERROUS metalS ELECTROLYSIS POLISHING ABRASIVE MAGNETIC field
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Optimizing Non-Ferrous Metal Value from MSWI Bottom Ashes 被引量:4
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作者 Simon P. M. Berkhout Bert P.M. Oudenhoven Peter C. Rem 《Journal of Environmental Protection》 2011年第5期564-570,共7页
The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. E... The bottom ashes resulted annually from the incineration of municipal solid waste in Europe contain about 400,000 tonnes of metallic aluminium and 200,000 tonnes of heavy non-ferrous metals, such as copper and zinc. Efficient recovery of this non-ferrous metal resource requires state-of-the-art separation technologies and a continuous feedback of laboratory analyses of the metal products and the depleted bottom ash to the operators of the bottom ash treatment plants. A methodology is presented for the optimization of the production of non-ferrous metal value from Municipal Solid Waste Incinerator bottom ash. Results for an incineration plant in the Netherlands show that efficient recycling can have a significant impact on value recovery as well as on non-ferrous metal recycling rates, producing up to 8% more revenue and 25% more metals from the ash. 展开更多
关键词 URBAN MINING Solid WASTE MSWI BOTTOM ASH non-Ferrous metalS
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Enhancing Production Efficiency of Oil and Natural Gas Pipes Using Microwave Technology
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作者 Wissam M. Alobaidi Entidhar A. Alkuam +1 位作者 Eric Sandgren Hussain M. Al-Rizzo 《Energy and Power Engineering》 2015年第10期440-450,共11页
The research reported in this paper aims at developing means of Non Destructive testing (NDT) to increase the line efficiency of pipe production in oil and natural gas pipe manufacturing plants using the Standard Allo... The research reported in this paper aims at developing means of Non Destructive testing (NDT) to increase the line efficiency of pipe production in oil and natural gas pipe manufacturing plants using the Standard Allowed Minutes (SAM) method. Existing line production stations encounter difficulties in maintaining the recommended testing speed of smaller diameter pipe, due to limitations in the Visual Inspection (VI) station. We propose to implement one additional technique which will prevent the decline of line efficiency in a pipe production factory. The range of diameters identified as a problem in this research is from 254 mm to 762 mm. Microwave techniques are expected to improve the line efficiency by increasing the production of the plant. This happens as a consequence of maintaining the production rates of the identified pipe diameters, so that they equal the production output of the larger pipe diameters. We analyze the velocity traveled by the pipe through Radiographic Testing (RT) according to the VI output (production). The RT velocity is decreased for the diameters identified above, in order to maintain quality control and cover the shortcoming of the VI. The number of pipes produced is computed during shift hours of the factory and pipe lengths of the forming department are determined. We compare the output (production) of a series of NDT line stations with and without the microwave technique for the first of the three pipe cases considered in this study, classified as perfect pipe (PP), repair pipe (RP) and scrap pipe (SP). The velocity of RT stations analyzed in the paper ranges from 50 mm/s for larger diameter pipe, and decline to 16.667 mm/s for the identified diameters. The analytical calculations of line output (production) and line efficiency demonstrate the solution of this velocity problem after the microwave technique is introduced. It demonstrates that an economical and precise methodology to extend the production capability of the pipe plant has been determined. 展开更多
关键词 Microwave Technology non Destructive Testing (NDT) SPIRAL pipe Process (SPP) pipe Inspection Standard Allowed Minutes (SAM)
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Preparation and Microstructural Analysis of Smelting Waste Non-ferrous Metal Slag Geopolymer 被引量:1
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作者 赵晶 ZHANG Yuxuan ZHANG Yaowen 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第6期1388-1391,共4页
The geopolymer samples were prepared with smelting waste slag of non-ferrous metal as the raw material and water glass as the activator. The effect of modulus of water glass and water binder ratio on the compressive s... The geopolymer samples were prepared with smelting waste slag of non-ferrous metal as the raw material and water glass as the activator. The effect of modulus of water glass and water binder ratio on the compressive strength was studied. The results show that the strength of the geopolymer activated by water glass with modulus of 1.1 and water binder ratio of 0.28 can maintain an increasing trend in the 90 curing days. Through the analyses with XRD, SEM(EDS), and FTIR, the main reaction products are found to be geopolymer gels, which bond the crystalline minerals to provide strength. The molecular chains of amorphous phase in slag become shorter after depolymerization-polycondensation. 展开更多
关键词 smelting waste slag of non-ferrous metal GEOPOLYMER compressive strength microstructureanalysis
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Role of local coordination in bimetallic sites for oxygen reduction: A theoretical analysis 被引量:1
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作者 Yuqi Yang Hao Zhang +8 位作者 Zhaofeng Liang Yaru Yin Bingbao Mei Fei Song Fanfei Sun Songqi Gu Zheng Jiang Yuen Wu Zhiyuan Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第5期131-137,共7页
Understanding of the oxygen reduction reaction(ORR)mechanism for single atom catalysts is pivotal for the rational design of non-precious metal cathode materials and the commercialization of fuel cells.Herein,a series... Understanding of the oxygen reduction reaction(ORR)mechanism for single atom catalysts is pivotal for the rational design of non-precious metal cathode materials and the commercialization of fuel cells.Herein,a series of non-precious metal electrocatalysts based on nitrogen-doped bimetallic(Fe and Co)carbide were modeled by density functional theory calculations to predict the corresponding reaction pathways.The study elucidated prior oxygen adsorption on the Fe atom in the dual site and the modifier role of Co atoms to tune the electronic structures of Fe.The reaction activity was highly correlated with the bimetallic center and the coordination environment of the adjacent nitrogen.Interestingly,the preadsorption of*OH resulted in the apparent change of metal atoms'electronic states with the d-band center shifting toward the Fermi level,thereby boosting reaction activity.The result should help promote the fundamental understanding of active sites in ORR catalysts and provide an effective approach to the design of highly efficient ORR catalysts on an atomic scale. 展开更多
关键词 non-precious metal catalysts Bimetallic-sites Oxygen reduction reaction Density functional theory
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