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Microscopic phase-field simulation for nucleation incubation time of Ni_(75)Al_xV_(25-x)alloy

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Journal of Central South University of Technology 2005年第6期12卷 635-640页

作者：李永胜陈铮卢艳丽王永欣张建军 School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 China

With the microscopic phase-field dynamic model, the effects of temperature and concentration on the nucleation incubation time of Ni75AlxV25-x alloy were studied and the relation between the incubation time and precipitation mechanism was investigated by using the atomic occupation probability picture and average order parameter curve. The simulation results demonstrate that there exists the incubation time for different precipitation mechanisms~ such as non-classical nucleation, the mixed style of non-classical nucleation and spinodal decomposition, and spinodal ordering; and the incubation time shortens in turn for the three kinds of mechanisms. With the increase of Al content of Ni75AlxV25-x alloy, the incubation time of Llz phases shortens continuously and that of DOzz phases is prolonged. The effects of temperature on the incubation time of Llz and DOzz phases are accordant, i.e. the incuba- tion time is greatly prolonged with the temperature rising.

关键词： microscopic phase-field nucleation incubation time order parameter simulation

Modeling of incubation time for Austenite to Ferrite Phase Transformation

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Journal of Iron and Steel Research International 2006年第4期13卷 32-34,60页

作者： ZHOU Xiao-guan LIU Zhen-yu WU Di WANG Wei JIAO Si-hai State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China Institute of Research and Development Baoshan Iron and Steel Co Ltd Shanghai 201900 China

On the basis of the classical nucleation theory, a new model of incubation time for austenite to ferrite transformation has been developed, in which the effect of deformation on austenite has been taken into consideration. To prove the precision of modeling, ferrite transformation starting temperature （Ar3） has been calculated using the Scheil＇s additivity rule, and the Ar3 values were measured using a Gleeble 1500 thermomechanical simulator. The Ar3 values provided by the modeling method coincide with the measured ones, indicating that the model is precise in oredicting the incubation time for austenite to ferrite transformation in hot deformed steels.

关键词： incubation time austenite to ferrite transformation hot deformation modeling

EFFECT OF AUSTENITE DEFORMATION ON ISOTHERMAL incubation time OF PROEUTECTOID FERRITE NUCLEATION

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Acta Metallurgica Sinica(English Letters) 1991年第3期4卷 161-164页

作者： LI Jian SUN Fuyu Central Iron and Steel Research Institute,Ministry of Metallurgical Industry,Beijing,China

A calculation method for the isothermal nucleation incubation time of pro-eutectoid ferrite formed from deformed austenite has been developed by introducing Feder's incubation time expression into the decomposition of deformed *** effects of austenite deformation stored energy and austenite grain boundary energy change on the incubation time have been theoretically calculated and the rule of calculated results is consistent with that of experiments,this confirms that austenite deformation stored energy and the change of austenite grain boundary energy are the natural effect of austenite deformation on ferrite nucleation.

关键词： deformed austenite ferrite incubation time

incubation time CONCEPT IN PROBLEMS OF PULSED STRENGTH OF CONTINUA:FRACTURE,CAVITATION,AND ELECTRICAL BREAKDOWN

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INCUBATION TIME CONCEPT IN PROBLEMS OF PULSED STRENGTH OF CO...

Optimization of Bacterial Doses and incubation time on Bio-Ehanol Fermentation of Nipah （Nypa fruticans） for Biofuel Energy

祝贺郑哲敏先生八十华诞应用力学报告会

作者： Yuri V.Petrov St.-Petersburg State University NIIMMUniversitetsky Prospect28PetrodvoretsSt.-Petersburg199178Russia

Experiments on the dynamic fracture of solids,hquids,conductors,andinsulators that is caused by fast intense actions of environment or directed energy fluxesreveal a number of effects indicating a fundamental difference between the fast dynamicrupture(breakdown)of materials and a similar process under slow quasistatic *** example,one of the basic problems in testing the dynamic-strength properties of ma-terials is associated with the dependence of the limiting characteristics on the duration,amplitude,and growth rate of an external action,as well as on a number of other *** a critical value is a constant for a material in the static case,experimentallydetermined critical characteristics in dynamics are strongly unstable,and as a result,their behavior becomes *** indicated(and some other)features of thebehavior of materials subjected to pulsed actions are common for a number of seeminglyquite different paysical processes,such as dynamic fracture(starting cracks and scab-bing),cavitation in liquids,and electrical breakdown in *** this paper,we analyzeexamples illustrating typical dynamic effects inherent in these *** propose aunified interpretation for the fracture of solids and liquids and electrical breakdown ininsulators using the structural-time approach[1,2]based on the concept of the fractureincubation time.

关键词： pulsed strength incubation time spalling fracture cavitation in fluids electrical breakdown

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Journal of Life Sciences 2011年第12期5卷 1022-1029页

作者： Wiludjeng Trisasiwi Ari Asnani Retna Setyawati Agricultural Engineering Jenderal Soedirman University Purwokerto 53123 Indonesia Chemistry Jenderal Soedirman University Purwokerto 53123 Indonesia Food Science and Technology Jenderal Soedirman University Purwokerto 53123 Indonesia

Nipah （Nypafruticans） is a species of palm trees that grows in mangroves environment near the sea shore. Nipah is potential to produce biofuel energy. The purposes of this research were 1） to determine the optimum bacterial concentration for fermentation to produce high concentration of bio-ethanol, and 2） to determine the optimum incubation time for fermentation to produce high concentration of bio-ethanol. The research had been conducted from June until November 2009 using nipah sap as the substrate and Saceharomyces cerevisiae as a fermentation starter. The experimental design used was a randomized block design （RBD）. Factors tested were starter concentration （5%, 7.5%, 10%） and incubation time （2, 4, 6 days）. The variables observed were concentration of reducing sugar, total microorganism （CFU/mL）, and bio-ethanol production. The results showed that the highest yield of bio-ethanol （8.98%） was produced with 7.5% of starter concentration and 6 days of incubation time.

关键词： Bio-ethanol bacterial concentration incubation time Nypafruticans Saccharomyces cerevisiae

Relationship between Hydrogen Diffusion and Blistering Nucleation and Growth

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Journal of Iron and Steel Research International 2016年第11期23卷 1188-1194页

作者： Jin-xu LI Hang YIN Xi-na YANG Qian LI Ping ZHANG Chun-qian XIE Yan-jing SU Li-jie QIAO Corrosion and Protection Center Environment Sensitive Fracture Laboratory(MOE)University of Science and Technology Beijing

The formation condition of hydrogen blister in 18Ni maraging steel without any inner or external stress was investigated. The results show that the critical diffusible hydrogen concentration of a blister forming is about 1.4×10^-5 , which is corresponding to the current density of 30 mA/cm^2 during cathodic charging in a sodium hydroxide solution. For a 0.1 cm thick sample, no matter the current density is equal to or much larger than the critical value, it spends at least about 132 h to form a hydrogen blister when hydrogen charging in single direction. It is approxi- mately equal to the time for hydrogen atom to diffuse throughout the sample, which exactly depends on the hydrogen diffusion coefficient and the penetration depth. The very first clear suggestion was reported that the incubation period for hydrogen blister nucleation was necessary. According to the Fick＇s laws, calculations show that the normalized hydrogen concentration in the escaping surface almost reaches 0.96 times of the charging surface, which means that the diffusion almost reaches a dynamic balance. A model was illustrated to describe the competitive relationship between hydrogen diffusion and blister formation.

关键词： hydrogen blister trap maraging steel hydrogen diffusion incubation time

Modeling of Austenite Decomposition in Low Si-Mn TRIP Steel During Cooling

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Journal of Iron and Steel Research International 2008年第6期15卷 68-71页

作者： ZHU Li-juan WU Di ZHAO Xian-ming College of Materials Science and Engineering Jilin University Changchun 130025 Jilin China The State Key Laboratory of Rolling Technology and Automation Northeastern University Shenyang 110004 Liaoning China

Transformation behavior in low carbon Si Mn TRIP steel was investigated by means of microstructural ob servation and computer modelling. A transformation model in which transformation is controlled by carbon diffusion was suggested, which well described the volume fractional change of ferrite, pearlite, and bainite during continuous cooling. The influence of Si content and austenite grain size was thoroughly investigated. The calculated results indicated that Si retards pearlite transformation, accelerates polygonal ferrite transformation, refines the austenite grain, and increases the ferrite transformation rate.

关键词： TRIP steel transformation incubation time ferrite bainite pearlite

Effects of sugarcane residue biochar and P fertilizer on P availability and its fractions in a calcareous clay loam soil

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Biochar 2020年第3期2卷 357-367页

作者： Mina Safian Hamidreza Motaghian Alireza Hosseinpur Department of Soil Science College of AgricultureShahrekord UniversityShahrekordIran

Biochar has the potential to affect the cycle of phosphorus(P),but the underlying mechanisms of its effects remain poorly understood in calcareous *** understanding of the effects of biochar is limited in calcareous soils during ***,this study was conducted to investigate how the availability and mineral fractions of P change after the addition of combined biochar and P fertilizer during incubation in calcareous *** residue(raw SR)and biochar(400℃for 2 h)were added to soils treated with 50 mg kg−1 of P,in the form of Ca(H_(2)PO_(4))_(2)·H_(2)O,at 0.5 and 1%(w/w).The soils were incubated at 25±1℃for 120 *** P(Olsen P)contents and mineral P fractions were measured after various incubation times(7,30,90,and 120 days).Biochar addition remarkably increased the amount of available P when compared with the raw SR treatment and the control condition(Pincubation,the amount of available P in the soils decreased and remained unchanged *** results indicated that the addition of 50 mg kg−1 of P as fertilizer significantly augmented the labile P and P associated with Fe and Al in all the treatments at all incubation times(Pincubation ***,we conclude that sugarcane residue biochar can enhance the available P in calcareous soils.

关键词： Organic amendment incubation time Available pool

Effects of Temperature on Determination of Protein Concentration with Coomassie Brilliant Blue Method

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Agricultural Science & Technology 2015年第2期16卷 209-213页

作者：赵卓孙文斌嵇雅茹郝锡联吉林师范大学生命科学院吉林四平136000

[Objective] This study aimed to investigate the effects of temperature on determination of protein concentration with Coomassie Brilliant Blue method,thus proving advice and guidance for accurate determination of protein concentration.[Method] With Coomassie Brilliant Blue method,the concentrations of different bovine serum albumin samples were determined under different temperatures and incubation time.[Result] According to the standard curve,when the determination range of protein concentration was 0-100 mg/ml,the determined protein concentration was relatively stable after incubation at 20 ℃ for 20-30 ***,the determination result of higher protein concentration with Coomassie Brilliant Blue method was less affected by various factors.[Conclusion] In determination of protein concentration with Coomassie Brilliant Blue method,temperature,sample concentration and incubation time were important factors affecting the accuracy of experimental results.

关键词： Coomassie Brilliant Blue method Protein Temperature Concentration incubation time