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Surface Modification With Zinc and Zn-Ni Alloy Compositionally Modulated Multilayer Coatings

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Journal of Iron and Steel Research International 2006年第4期13卷 61-67页

作者： FEI Jing-yin liANG Guo-zheng XIN Wen-li WANG Wei-kang Department of Applied Chemistry Northwestern Polytechnical University Xi＇an 710072 Shaanxi China

Zinc and Zn-Ni alloy compositionally modulated multilayer （CMM） coatings were electrodeposited on to a steel substrate by the successive deposition of zinc and Zn-Ni alloy sublayers from dual baths. The coated samples were evaluated in terms of the surface appearance, surface and cross-sectional morphologies, as well as corrosion resistance. The microstructural characteristics that were examined using the field emission gun scanning electron microscopy （FEGSEM） confirmed the layered structure, grain refinement of the zinc and Zn-Ni alloy CMM coatings, and revealed the existence of microcracks caused by the internal stress in the thick Zn-Ni alloy sublayers. The corrosion resistance that was evaluated by means of the salt spray test shows that the zinc and Zn-Ni alloy CMM coatings were more corrosion-resistant than the monolithic coatings of zinc or Zn-Ni alloy of the same thickness. The possible reasons for the better protective performance of Zn-Ni/Zn CMM coatings were given on the basis of the analysis on the micrographic features of zinc and Zn-Ni alloy CMM eoatings after the corrosion test. A probable corrosion mechanism of zinc and Zn-Ni alloy CMM coatings was also proposed.

关键词： electrodeposition compositionally modulated multilayer coating Zn-Ni alloy corrosion resistance

Software Defect Prediction Method Based on Stable Learning

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Computers, Materials & Continua 2024年第1期78卷 65-84页

作者： Xin Fan Jingen Mao liangjue lian li Yu Wei zheng Yun Ge College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjing210012China School of Software Nanchang Hangkong UniversityNanchang330029China Software Testing and Evaluation Center Nanchang Hangkong UniversityNanchang330029China

The purpose of software defect prediction is to identify defect-prone code modules to assist software quality assurance teams with the appropriate allocation of resources and *** previous software defect prediction studies,transfer learning was effective in solving the problem of inconsistent project data ***,target projects often lack sufficient data,which affects the performance of the transfer learning *** addition,the presence of uncorrelated features between projects can decrease the prediction accuracy of the transfer learning *** address these problems,this article propose a software defect prediction method based on stable learning(SDP-SL)that combines code visualization techniques and residual *** method first transforms code files into code images using code visualization techniques and then constructs a defect prediction model based on these code *** the model training process,target project data are not required as prior *** the principles of stable learning,this paper dynamically adjusted the weights of source project samples to eliminate dependencies between features,thereby capturing the“invariance mechanism”within the *** approach explores the genuine relationship between code defect features and labels,thereby enhancing defect prediction *** evaluate the performance of SDP-SL,this article conducted comparative experiments on 10 open-source projects in the PROMISE *** experimental results demonstrated that in terms of the F-measure,the proposed SDP-SL method outperformed other within-project defect prediction methods by 2.11%-44.03%.In cross-project defect prediction,the SDP-SL method provided an improvement of 5.89%-25.46% in prediction performance compared to other cross-project defect prediction ***,SDP-SL can effectively enhance within-and cross-project defect predictions.

关键词： Software defect prediction code visualization stable learning sample reweight residual network

Dynamic cache resources allocation for energy efficiency

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The Journal of China Universities of Posts and Telecommunications 2009年第1期16卷 121-126页

作者： CHEN li-ming ZOU Xue-cheng LEI Jian-ming liU zheng-lin Department of Electronics Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

This article proposes a mechanism of low overhead and less runtime, termed dynamic cache resources allocation （DCRA）, which allocates each application with required cache resources. The mechanism collects cache hit-miss information at runtime and then analyzes the information and decides how many cache resources should be allocated to the current executing application. The amount of cache resources varies dynamically to reduce the total number of misses and energy consumption. The study of several applications from SPEC2000 shows that significant energy saving is achieved for the application based on the DCRA with an average of 39% savings.

关键词： cache energy consumption microprocessor

High Temperature Rapid Tempering Process of SS400 Steel With Thermomechanical Simulation Tester

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Journal of Iron and Steel Research International 2012年第2期19卷 43-49页

作者： XING Shu-qing CHEN zheng-zong MA Yong-lin li Hui-qin School of Material and Metallurgy Inner Mongolia University of Science and Technology Baotou 014010Inner Mongolia China The State Key Laboratory of Roiling and Automation Northeastern UniversityShenyang 110004 Liaoning China

The effect of refined precipitations and dispersed phases on the toughness of SS400 steel was investigated by rapid tempering with thermomechanical simulation tester, and the electromagnetic induction rapid tempering process was simulated. The conventional tempering and rapid tempering process were proceeded respectively, and both samples were quenched in 10~ of agitated iced brine. The tempering temperatures were designed as 560, 620 and 680℃, respectively. Rapid tempering specimens were heated at a heating rate of 20 ℃/s, and all samples of these three tempering temperatures were maintained 30, 40 and 50 s with the Gleeble1500-D tester, respectively. The impact test at --40 ℃ were carried out on a Charpy impact machine （CBD-300） with a maximum measurement range of 300 J and the microstructures were analyzed in detail using optical microscope （OM） and scanning electron microscope （SEM）. The experiment results show that the upper bainite, martensite and small amount of austenite were obtained in the rapidly quenched samples. In comparison to the conventional process, the matrix microstructure was changed from the larger size and bulk ferrite to the refined banding structure, and the cementites were obviously refined and precipitated inside the grains and along the grain boundaries. The cryogenic impact test implies that the maximum values of impact toughness with holding time of 30 or 50 s are achieved at tempering temperature of 620℃. Furthermore, a favorite value of impact toughness with holding time of 40 s is available.

关键词： SS400 steel rapid tempering process thermomechanical simulation tester precipitation cryogenic impact toughness

Effect of Transverse Static Magnetic Field on Droplets Transient and Inclusions Evolution During the Electroslag Remelting Process of GCr15 Ingots

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1311-1316页

作者： Qiang li Yun-Bo Zhong Chu-Xiong Sun Huai Wang Tian-Xiang zheng Wei-li Ren Zhong-Ming Ren State Key Laboratory of Advanced Special Steels Shanghai University

The voltage was recorded to investigate the influence of the static magnetic field on droplet evolution during the mag-netically controlled electroslag remelting （MC-ESR） process. MC-ESR experiments were carried out under differentremelting current, and transverse static magnetic fields （TSMF） of 85 mT, 130 mT and 160 mT were *** work was performed to obtain the quantitative data of the droplets. The ASPEX Explorer was utilized toinvestigate the inclusions evolution of GCr15 ingots. The number of the droplets was 31 in 20 s during the traditional ESRprocess and reached 50 and 51 under the MC-ESR process with the TSMF of 85 mT and 130 mT, respectively. Whencompared the traditional ESR process with the MC-ESR process, the inclusions amount reduced 67%.

关键词： Electroslag remelting Static magnetic field Droplet transient Inclusions evolution Electromagnetic vibration effect

A new method for detecting line spectrum of ship-radiated noise using Duffing oscillator

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Chinese Science Bulletin 2007年第14期52卷 1906-1912页

作者： zheng SiYi GUO HongXia li YaAn WANG BingHe ZHANG PengYi Department of Communication Engineering Engineering College of the Chinese People's Armed Police Force Xi'an 710086 China Department of Basic Science Engineering College of the Chinese People's Armed Police Force Xi'an 710086 China College of Marine Engineering Northwestern Polytechnic University Xi'an 710072 China

A detection scheme for line spectrum of ship-radiated noise is proposed using Duffing oscillator. The chaotic trajectory of Duffing oscillator is analyzed and the state equation of the system is improved to detect weak periodic signals in different frequencies. According to the simulation results, the phase transforms of Duffing oscillator are sensitive to periodic signals and immune to the random noise and the periodic interference signals which have larger angular frequency difference from the referential signal. By employing Lyapunov exponents in the field of detection as the criteria for chaos, the phase transforms of dynamic behaviors in quantity are successfully determined. Meanwhile, the threshold value in critical state has been evaluated more accurately. Based on the phase transforms of Duffing oscillator, a new method for detecting line spectrum of ship-radiated noise is given. Three types of ship-radiated noise signals are analyzed and the values of line spectrum are acquired successfully by this method. The experimental results show that this method has high sensitivity and high resolution.

关键词：光谱噪声煤粉震荡器混沌学说

Effects of maltogenicα-amylase treatment on the proportion of slowly digestible starch and the structural properties of pea starch

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Food Bioscience 2022年第4期48卷 551-558页

作者： Yi zheng Huanxin Zhang Ruomin li Xiaoling Zhu Mengwei Zhu School of Food Science and Technology Jiangsu Agri-animal Husbandry Vocational CollegeTaizhou225300PR China College of Food Science and Engineering Jiangsu Ocean UniversityLianyungang222005China

In this study,pea starch was modified with maltogenicα-amylase and then its physicochemical properties,chain length distribution,and in vitro digestibility were *** analysis of the starch products resulting from the maltogenicα-amylase treatment revealed a decrease in the molecular weight,an increase in the proportion of short chains[degree of polymerization(DP)13),and a decrease in viscosity,resulting in slower *** results indicated that maltogenicα-amylase can selectively hydrolyzeα-1,4-andα-1,6-glycosides to some *** theα-1,4 linkage of starch facilitated the transfer of the non-reducing D-glucosyl residues of maltose,thereby generating anα-1,6 branch *** reaction between maltogenicα-amylase and pea starch was affected by the reaction time and enzyme *** maximum slowly digestible starch content(38.5%)was obtained by digesting samples with 60.0 ppm maltogenicα-amylase for 4.0 *** findings demonstrate that modifying pea starch using maltogenicα-amylase can generate starch products with new branching structures conducive to slow digestion.

关键词： Pea starch Maltogenicα-amylase Slowly digestible starch(SDS) Glycemic index(GI) Enzymatic modification Hydrolysis

Giant Stress-Impedance Effect in Co_(71.8)Fe_( 4.9)Nb_(0.8)Si_(7.5)B_(15) Glass-Covered Amorphous Wires

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Journal of Iron and Steel Research International 2006年第4期13卷 49-50,74页

作者： CHEN zheng li De-ren LU Zhi-chao ZHOU Shao-xiong Nanomaterials Engineering and Research Center Central Iron and Steel Research Institute Beijing 100081 China Research and Development Center Advanced Technology and Materials Co Ltd Beijing 100081 China

The giant stress-impedance （GSI） effect in as-cast and DC current annealed Co71.8Fe4.9 Nb0.8Si7.5 B15 amorphous glass-covered wires is presented. The SI ratio of the as-cast sample exhibits negative GSI effect. For the sample annealed by 60 mA DC current, the SI ratio first increases with applied tensile stress, then decreases. The maximum ΔZ/Z ratio of 304% is obtained. Frequency dependence in the range from 1 to 110 MHz of the GSI effect is investigated. Experimental results show that the real part R and the imaginary part X of impedance play an important role at high frequency and low frequency, respectively. At 1 MHz, the maximum AX/X ratio of 1448% is obtained. At 110 MHz, the maximum AR/R ratio of 648% is obtained.

关键词： giant stress-impedance amorphous wire DC annealing

Dynamic control on grain-size distribution of terrigenous sediments in the western South China Sea:Implication for East Asian monsoon evolution

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Chinese Science Bulletin 2008年第10期53卷 1533-1543页

作者： CHEN GuoCheng zheng HongBo li JianRu XIE Xin MEI Xi State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China

High-resolution oxygen isotope stratigraphy of Core MD05-2901, which is located off eastern Vietnam in the western South China Sea (SCS), was established and indicated that the core spans a time period of the past 450 ka. Based on the bulk density, fractional porosity and lithogenic content of the sedi-ments, terrigenous mass accumulation rate (TMAR) was obtained, which is 4.9―6.0 g cm?2 ka?1 on average during interglacial stages, higher than that during glacial stages, i.e. 1.9―5.0 g cm-2 ka-1, which is different from northern and southern SCS which show higher TMAR in glacial stages. By principle component analysis of grain size distribution of all the samples, two main control factors (F1 and F2) were obtained, which are responsible for about 80% variance of granularity. The contents of grain size population 1.26―2.66 μm% and 10.8―14.3 μm% which are sensible to F1 show high-frequency fluctuation, and correlate well with the summer insolation at 15oN. They exhibit a dis-tinct cyclicity with frequencies near 23 ka and 13 ka, in contrast to a strong frequency peak near 100 ka obtained in proxies 4.24―7.42 μm% and 30.1―43.7 μm% controlled mainly by F2. The sedimentary character of this part of the SCS was controlled by variations of input flux from two main source areas, namely the southwest and north SCS, which were transported by different circulations of surface current forced by East Asian summer monsoon and winter monsoon respectively. We believe that the East Asian summer monsoon has fluctuated with high frequency and been forced by changes in solar in-solation in low latitude associated with precession and half precession, while ice-volume forcing is probably a primary factor in determining the strength and timing of the East Asian winter monsoon but with less important insolation forcing.

关键词：南中国海陆源沉积物颗粒尺寸东亚季风