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A Novel Process in Semi-Solid Metal Casting

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Journal of Materials Science & Technology 2012年第10期28卷 946-950页

作者： Bijan Abbasi-Khazaei Saeid Ghaderi Department of Material eng. Faculty of Eng.Razi University

In this research a new process for semi-solid casting of ductile iron based on the high nucleation rate combined with locally mechanical stirring is presented. In this process at first fully liquid ductile iron was poured on the peripheral surface of a wheel rotating against pouring direction. At this stage, the solid crystals nucleated at the chilling surface were pushed to the melt by a heat resistance steel cutter and finally the semi-solid slurry was generated. Reheating treatment was done on the samples to achieve more efficiency of semi-solid casting process. The effects of the travelling distance of solid particles during casting, the reheating time and temperature were examined. The results showed that the process effectively changes the dendrite structure to globular one.

关键词： Semi-solid Casting Ductile cast iron

Hydrodynamic Performance of Vertical Porous Structures Under Regular Waves

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China Ocean eng.neering 2013年第4期27卷 451-468页

作者： A.S.Koraim O.S.Rageh Water and Water Structure eng. Dept. Faculty of Eng. Zagazig University Irrigation and Hydraulics Dept. Faculty of Eng. El-Mansoura University

The hydrodynamic efficiency of the vertical porous structures is investigated under regular waves by use of physical models. The hydrodynamic efficiency of the breakwater is presented in terms of the wave transmission （kt）, reflection （kr） and energy dissipation （ka） coefficients. Different wave and structural parameters affecting the breakwater efficiency are tested. It is found that, the transmission coefficient （kt） decreases with the increase of the relative water depth （h/L）, the wave steepness （Hi^L）, the relative breakwater widths （B/L, B/h）, the relative breakwater height （D/h）, and the breakwater porosity （n）. The reflection coefficient （kr） takes the opposite trend of kt when D/h=l.25 and it decreases with the increasing h/L, HJL and B/L when D/h〈1.0. The dissipation coefficient （kd） increases with the increasing h/L, HilL and B/L when D/h〈_l.O and it decreases when D/h=l.25. In which, it is possible to achieve values ofkt smaller than 0.3, k~ larger than 0.5, and kd larger than 0.6 when D/h=1.25, B/h=0.6, h/L〉0.22, B/L〉O. 13, and H/L 〉0.04. Empirical equations are developed for the estimation of the transmission and reflection coefficients. The results of these equations are compared with other experimental and theoretical results and a reasonable agreement is obtained.

关键词： water waves porous breakwaters wave attenuation wave transmission wave reflection wave dissipation

Effects of Nickel Distribution on the Streng.hening and Toughening of Alumina Ceramics

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Journal of Materials Science & Technology 2008年第5期24卷 723-728页

作者： Mohamed.M.El-Sayed Seleman Department of Materials and Metallurgical eng. Faculty of Petroleum and Mining Eng.Post Code 43721SuezEgypt

Three types of composite materials were designed and fabricated by hot pressing powder blends of alumina with 20 vol. pct nickel particles. The composites differ in the shape, size and distribution of the nickel particles. Composite microstructures are described and measurements of density, hardness, flexure streng.h, and fracture toughness are reported. The results showed that the fracture streng.h of the composite with dispersed nickel particles is higher than the other two composites （network microstructure and mixed microstructure） and the alumina matrix. For all the composites studied, tougher materials than the monolithic alumina were produced. The fracture toughness of the composite with a network microstructure is much higher than that of the other composites. The toughening mechanisms were described based on the observation of the fracture surfaces and the crack-particle interactions. Moreover, the parameters for microstructural tailoring of these materials have been deduced. The toughening of the produced composites was explained in light of the interracial bond streng.h.

关键词： Alumina-nickel composites Nickel morphology Interfacial bonding Fracturetoughness Flexure streng.h

赛德西港用于船舶减排的陆上可再生能源供电评估

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哈尔滨工程大学学报（英文版） 2024年第2期23卷 506-524页

作者： Merna Makram Ameen M.Bassam Adel A.Tawfik Waleed Yehia Naval Architecture and Marine eng.Dept. Faculty of EngineeringPort Said UniversityPort Fuad 42526Egypt

Air pollution from shipping is becoming a critical issue,particularly in dense hub port *** proposed solution to minimize ship-based emissions at ports is the implementation of an Onshore Power Supply(OPS)*** allows ships to shut off their auxiliary eng.nes and instead connect to the port *** there have been numerous studies conducted on ports in Europe and the United States,little research has been done on Egyptian ***,this paper aims to investigate the feasibility of implementing OPS at Port Said West Port in Egypt,aligning with Egypt Vision 2030’s goals for addressing climate *** research primarily focuses on analyzing data collected from calling ships to generate socio-economic and cost-effectiveness analyses of *** further enhance the environmental benefits of OPS,the paper proposes the use of solar energy as the OPS electricity *** findings of the study revealed that by relying on the national grid,emissions can be reduced by 28%.Moreover,it is predicted that this reduction could reach 100%if electricity generation is solely based on solar ***,the economic analysis demonstrates promising profitability,with a payback period of approximately two years.

关键词： Onshore power supply Port sustainability Shipping emissions inventory Solar energy Photovoltaic systems

The Research Existing Condition and Application of Solid Waste Disposal in Japan

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四川大学学报（工程科学版） 2009年第S1期41卷 62-69页

作者： TANAKA Reiji KITATSUJI Masafumi faculty of eng. Tohoku Inst.e of Technol. Miyagi Univ.

Japan lacked resources is a large import country and also a large consuming *** it is turned society structure system of consumption goods stocked in domestic,which leads to 450 millions ton waste ***,because of continuing development of intermediate handling and recycled utilization technology,finally disposed waste materials approximately 30 millions *** quantity of concrete product is consumed 300 millions ton per year unprecedented,beau case of large scope,it is expected valid and large absorption industry of recycled material. The purpose of this paper is to do a report on applied present status and future assignment of recycled material and building structure in Japan.

关键词： inorganic waste recycled aggregate circumstance security precast concrete product reinforced concrete structure

Design of a Proportional-Integral-Derivative Controller for an Automatic Generation Control of Multi-area Power Thermal Systems Using Firefly Algorithm

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 503-515页

作者： K.Jagatheesan B.Anand Sourav Samanta Nilanjan Dey Amira S.Ashour Valentina E.Balas the Department of Electrical & Electronics eng. Mahendra Institute of Eng. & Tech. the Department of Electrical & Electronics eng. Hindusthan College of Eng. & Tech. the Department of Computer Science & eng.neering University Institute of Technology The University of Burdwan the Department of Information Technology Techno India College of Technology the Department of Electronics and Electrical Communications eng.neering Faculty of Engineering Tanta University the faculty of eng.neering Aurel Vlaicu University of Arad

Essentially, it is significant to supply the consumer with reliable and sufficient power. Since, power quality is measured by the consistency in frequency and power flow between control areas. Thus, in a power system operation and control,automatic generation control(AGC) plays a crucial role. In this paper, multi-area(Five areas: area 1, area 2, area 3, area 4 and area 5) reheat thermal power systems are considered with proportional-integral-derivative(PID) controller as a supplementary controller. Each area in the investigated power system is equipped with appropriate governor unit, turbine with reheater unit, generator and speed regulator unit. The PID controller parameters are optimized by considering nature bio-inspired firefly algorithm(FFA). The experimental results demonstrated the comparison of the proposed system performance(FFA-PID)with optimized PID controller based genetic algorithm(GAPID) and particle swarm optimization(PSO) technique(PSOPID) for the same investigated power system. The results proved the efficiency of employing the integral time absolute error(ITAE) cost function with one percent step load perturbation(1 % SLP) in area 1. The proposed system based FFA achieved the least settling time compared to using the GA or the PSO algorithms, while, it attained good results with respect to the peak overshoot/undershoot. In addition, the FFA performance is improved with the increased number of iterations which outperformed the other optimization algorithms based controller.

关键词： Automatic generation control(AGC) firefly algorithm genetic algorithm(GA) particle swarm optimization(PSO) proportional-integral-derivative(PID) controller

Unsteady Correlation between Pressure and Temperature Field on Impinging Plate for Dual Underexpanded Jets

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Journal of Thermal Science 2009年第3期18卷 215-219页

作者： Minoru YAGA Hiroyuki HIGA Shoichi MATSUDA Izuru SENAHA Depts. Mech. Systems eng. Univ. of the Ryukyus Graduate student Faculty of Eng. Univ. of the Ryukyus Okinawa National College of Technology

In this paper, dual underexpanded impinging jets are experimentally studied by measuring unsteady wall staticpressure and temperature fields using high response semiconductor pressure sensors and infrared imaging cam-era(100 captures per sec) with dual converging sonic nozzles. The flow field is also visualized by means of highspeed schlieren system( up to 70000 frame per second) to clarify the unsteady behavior of the jet structures suchas barrel shock wave, and Mach disk. Experiments were performed with a blow down tunnel changing the parameterssuch as the nozzle to plate distance, the distance between the two nozzles, and wind tunnel pressure *** nozzle to plate distance L and the distance between the two nozzles H are non-dimensionalized by the nozzlediameter D covering H/D=1.5, 2.0, and 3, L/D= 2, 3,and 4, and po/pb=1.0 - 5.0, where po and pb are stagnationpressure and back pressure respectively. Although the response of the infrared camera is quite different fromthat of the high speed camera, the unsteady correlation between the pressure and temperature fields is confirmedunder some conditions. Also the high speed schlieren pictures and the wall static pressure fluctuations suggestthat the generation of the Mach disk promote the unsteady behavior of the jets. After the confirmation of the correlation,a simple way to find the severe fluctuating region can be provided according to the two dimensional unsteadytemperature images without a lot of unsteady pressure measurements.

关键词： Shock wave CFD supersonic flow unsteady jet fluctuation

MATHEMATICAL MODEL OF THE MICROBIAL FLOODING

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Journal of Hydrodynamics 2003年第4期15卷 104-108页

作者： Lei Guang-lun, Zhang Zhong-zhi, Chen Yue-ming faculty of Chemical eng.neering, University of Petroleum, Beijing 102249, China faculty of Chem. eng. Univ. of Petroleum Beijing 102249 China

On the basis of growth kinetics of microorganism and the principle ofmaterial balance, equations were derived to describe microbial growth, nutrient consumption,metabolites production and their transport in formation. The changes in porosity, permeability, oilviscosity and capillary force were also described as the main facturs of microbial flooding. Forreservoirs with black oil properties, three-dimensional three-phase mathematical models with thecosidara-tion of multi-microbial components were established to depict microbial flooding oil. Withthis model, calculated results are in good agreement with experimental data.

关键词： microbial flooding enhance oil recovery mathematical model

Removal of Anionic Metal Ions from Wastewater by Hydroxide-type Adsorbents

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过程工程学报 2006年第3期6卷 357-362页

作者： Toyohisa Fujita Gjergj Dodbiba Jun Sadaki Atsushi Shibayama Dept. Geosystem eng. Graduate School Eng.The University of TokyoTokyo 113-8654Japan Dept. Material-Process. eng.&Appl. Chem. for Environ. Faculty Eng.&Resources Sci.Akita Univ.Akita 010-8502Japan

Generally speaking,anionic metal concentrations in wastewater from industries and mineral processing plants are well above the allowed limits for effluent set by the Ministry of Environment of Japan. Nowadays,the removal of anionic ions has been considered difficult and development of new process is desperately needed. In this paper,we report the development of three hydroxide-type adsorbents,illustrating their adsorption efficiency in removing As,Se,Mo and Sb ions from aqueous solutions. The main finding of this work was that the adsorption behavior was influenced very much by both the pH and the adsorbent concentration. Nevertheless,the newly developed hydroxide-type adsorbents were very effective in reducing the concentration of those anionic ions.

关键词： hydroxide-type adsorbent adsorption anionic metal ions removal wastewater