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Effect of rolling geometry on the mechanical properties, microstructure and recrystallization texture of Al–Mg–Si alloys

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International Journal of Minerals,Metallurgy and Materials 2015年第7期22卷 738-747页

作者： Xiao-feng Wang Ming-xing Guo Ling-yong Cao Fei Wang Ji-shan Zhang Lin-zhong zhuang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

The effect of rolling geometry on mechanical properties, microstructure, and recrystallization texture of Al-Mg-Si alloys was studied by means of tensile tests, microstrucmral observations, and electron backscatter diffraction measurements. The results reveal that the elongation and the average plasticity strain ratio （r） values of the T4P （pre-aging plus natural aging）-treated alloy sheet with a rolling geome- try value between 1 and 3 are somewhat higher than those of the T4P-treated sheet with a rolling geometry value between 3 and 6. The deformation and recrystallization microstructures of the sheet with a rolling geometry value between 1 and 3 are more uniform than those of the sheet with a rolling geometry value between 3 and 6. The former also possesses somewhat higher surface quality. H {001 } 〈110〉 and Goss {110}〈001〉 orientations are the main recrystallization texture components for the former case, whereas the latter case only includes H {001 } 〈 110〉 orientation. Texture gradients are present in the two alloy sheets. Shear texture component F on the surface of the sheet with a rolling geometry value between 3 and 6 and its higher texture gradients have revealed that non-uniform deformation occurred during cold rolling. The effects of texture on the yield strength and r value were also discussed.

关键词： aluminum-magnesium-silicon alloys rolling surface quality mechanical properties microstructure texture

Effect of Ni addition on microstructure and mechanical properties of Al–Mg–Si–Cu–Zn alloys with a high Mg/Si ratio

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 740-751页

作者： Gao-jie Li Ming-xing Guo Yu Wang Cai-hui Zheng Ji-shan Zhang Lin-zhong zhuang State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing

The effect of adding 0.03wt%Ni on the microstructure and mechanical properties of Al–Mg–Si–Cu–Zn alloys was systematically *** results reveal that the number density of spherical Fe-rich phases within grains increases with the addition of Ni,accompanied by the formation of Q(Al3Mg9Si7Cu2)precipitates around the spherical Fe-rich ***,Ni addition is beneficial to reducing the grain size in the as-cast *** the homogenization process,Q phases could be completely dissolved and the grain size could remain basically ***,compared with the Ni-free alloy,the Fe-rich phase in the Ni-containing alloy is more likely to undergo the phase transformation and further form more spherical particles during homogenization *** thermomechanical processing,the distribution of Fe-rich phases in the Ni-containing alloy was further greatly improved and directly resulted in a greater formability than that of the Ni-free ***,a reasonable Ni addition positively affected the microstructure and formability of the alloys.

关键词： Al-Mg-Si-Cu-Zn alloy Ni addition Fe-rich phase phase transformation formability

Staring-imaging satellite pointing estimation based on sequential ISAR images

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Chinese Journal of Aeronautics 2024年第8期37卷 261-276页

作者： Canyu WANG Libing JIANG Weijun zhong Xiaoyuan REN zhuang WANG National Key Laboratory of Automatic Target Recognition National University of Defense TechnologyChangsha 410073China Xi’an Satellite Control Center Xi’an 710600China

Pointing estimation for spacecraft using Inverse Synthetic Aperture Radar(ISAR)images plays a significant role in space situational awareness and ***,feature extraction and cross-range scaling of ISAR images create bottlenecks that limit performances of current estimation ***,the emergence of staring imaging satellites,characterized by complex kinematic behaviors,presents a novel challenge to this *** address these issues,this article proposes a pointing estimation method based on Convolutional Neural Networks(CNNs)and a numerical optimization algorithm.A satellite’s main axis,which is extracted from ISAR images by a proposed Semantic Axis Region Regression Net(SARRN),is chosen for investigation in this article due to its unique ***,considering the kinematic characteristic of the staring satellite,an ISAR imaging model is established to bridge the target pointing and the extracted *** on the imaging model,pointing estimation and cross-range scaling can be described as a maximum likelihood estimation problem,and an iterative optimization algorithm modified by using the strategy of random sampling-consistency check and weighted least squares is proposed to solve this ***,the pointing of targets and the cross-range scaling factors of ISAR images are *** experiments based on actual satellite orbital parameters verify the effectiveness of the proposed *** work can improve the performance of satellite reconnaissance warning,while accurate cross-range scaling can provide a basis for subsequent data processes such as 3D reconstruction and attitude estimation.

关键词： Staring-imaging Agile satellite Inverse Synthetic Aperture Radar(ISAR) Pointing estimation Cross-range scaling

Effect of particle size distribution on the microstructure,texture,and mechanical properties of Al–Mg–Si–Cu alloy

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 957-966页

作者： Xiao-feng Wang Ming-xing Guo Cun-qiang Ma Jian-bin Chen Ji-shan Zhang Lin-zhong zhuang The Faculty of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Capital Aerospace Machinery Company Beijing 100076China

The effect of particle size distribution on the microstructure,texture,and mechanical properties of Al–Mg–Si–Cu alloy was investigated on the basis of the mechanical properties,microstructure,and texture of the *** results show that the particle size distribution influences the microstructure and the final mechanical properties but only slightly influences the recrystallization *** the pre-aging treatment and natural aging treatment(T4 P treatment),in contrast to the sheet with a uniform particle size distribution,the sheet with a bimodal particle size distribution of large constituent particles and small dispersoids exhibits higher strength and a somewhat lower plastic strain ratio(r) and strain hardening exponent(n).After solution treatment,the sheet with a bimodal particle size distribution of large constituent particles and small dispersoids possesses a finer and slightly elongated grain structure compared with the sheet with a uniform particle size ***,they possess almost identical weak recrystallization textures,and their textures are dominated by CubeND {001} and P {011} orientations.

关键词： Al–Mg–Si–Cu alloy microstructure texture particle mechanical property

不同小体型肉鸭品系生长性能、屠宰性能和肉品质比较

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中国家禽 2024年第5期46卷 12-17页

作者：徐鸣鸿张傲贾雯茜庄重王志秀江勇白皓常国斌陈国宏扬州大学动物科学与技术学院江苏扬州225009 扬州大学农业科技发展研究院教育部农业与农产品安全国际合作联合实验室江苏扬州225009

为比较“益扬1号”两个专门化品系(H1♂×H1♀、H2♂×H2♀)及其杂交后代(H1♂×H2♀)生长性能、屠宰性能和肉品质,试验采用1日龄“益扬1号”两个专门化品系及其杂交后代各110只进行地面平养,记录生长性能,7周龄进行屠宰与肉品质测定。... 详细信息

为比较“益扬1号”两个专门化品系(H1♂×H1♀、H2♂×H2♀)及其杂交后代(H1♂×H2♀)生长性能、屠宰性能和肉品质,试验采用1日龄“益扬1号”两个专门化品系及其杂交后代各110只进行地面平养,记录生长性能,7周龄进行屠宰与肉品质测定。结果显示:7周龄时,H1♂×H2♀组体重低于H1♂×H1♀组,高于H2♂×H2♀组(P<0.05)。H1♂×H2♀组除胸深外,各项体尺指标均显著高于H2♂×H2♀组(P<0.05)。H1♂×H2♀组的腿比率、瘦肉率、腿肌率和胸肌率显著高于H1♂×H1♀和H2♂×H2♀组(P<0.05),屠宰率、全净膛率和半净膛率显著低于H1♂×H1♀和H2♂×H2♀组(P<0.05)。H1♂×H2♀组胸肌肉色a*显著高于H1♂×H1♀和H2♂×H2♀组(P<0.05),腿肌肉色b*低于H1♂×H1♀和H2♂×H2♀组(P<0.05)。H1♂×H2♀组剪切力显著低于H1♂×H1♀组(P<0.05),水分含量显著低于H2♂×H2♀组(P<0.05)。H1♂×H2♀组胸肌蛋白质含量和腿肌脂肪含量显著高于H1♂×H1♀和H2♂×H2♀组(P<0.05)。研究表明,H1和H2纯系经过杂交,生长性能和肉品质等指标得到改善。

关键词：优质肉鸭生长性能屠宰性状肉品质

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海南习用药材酸藤子的质量标准研究

生物资源 2024年第1期46卷 79-86页

作者：庄重沈青邱秀儒刘洋洋李文兰中国医学科学院药用植物研究所海南分所海南省南药资源保护与开发利用重点实验室海南海口570311 哈尔滨商业大学药学院黑龙江哈尔滨150076 琼海市中医院海南琼海571400

为了制定海南习用药材酸藤子的质量标准,以2020年版《中国药典》质量鉴定基本原则为指导,采用性状观察法、显微观察法、薄层色谱法、烘干法、总灰分测定法、水溶性热浸法、紫外-可见分光光度法分别研究酸藤子的性状和显微结构特征,水分... 详细信息

为了制定海南习用药材酸藤子的质量标准,以2020年版《中国药典》质量鉴定基本原则为指导,采用性状观察法、显微观察法、薄层色谱法、烘干法、总灰分测定法、水溶性热浸法、紫外-可见分光光度法分别研究酸藤子的性状和显微结构特征,水分、总灰分、水溶性浸出物以及总黄酮含量。明确了酸藤子性状和显微结构特征,建立了其薄层鉴别方法;拟规定酸藤子药材水分不得超过13.0%,总灰分不得超过12.0%,水溶性浸出物含量不得少于20.0%,总黄酮含量不得少于1.3%。初步拟定了海南习用药材酸藤子质量标准,为酸藤子进一步的质量控制和药用开发提供参考。

关键词：酸藤子质量标准习用药材

The risks of sulfur addition on cadmium accumulation in paddy rice under different water-management conditions

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Journal of Environmental Sciences 2022年第8期34卷 101-111页

作者： Zhe Liu Qi-qi Wang Si-yu Huang Ling-xuan Kong zhong zhuang Qi Wang Hua-fen Li Ya-nan Wan Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation Key Laboratory of Plant-Soil Interactions of the Ministry of EducationCollege of Resources and Environmental SciencesChina Agricultural UniversityBeijing 100193China

Recently, the application of sulfur(S) has been recommended to control the accumulation of cadmium(Cd) in rice in contaminated paddy soil. However, the effects of exogenous S on Cd transfer in paddy rice systems under different water-management practices have not been systematically investigated. Pot experiments were performed to monitor the composition of soil pore water and the Cd accumulation in iron plaque and rice tissue were compared under different S(0 and 200 mg/kg Na_(2)SO_(4)) and water(continuous and discontinuous flooding) treatments. Sulfur application significantly increased Cd concentrations in soil pore water under discontinuous flooding conditions, but slightly reduced them under continuous flooding. Moreover, the oxidation/reduction potential(Eh) was the most critical factor that affected the Cd levels. When the Eh exceeded-42.5 mV, S became the second critical factor, and excessive S application promoted Cd dissolution. In addition, S addition elevated the Cd levels in iron plaque and reduced the Cd transfer from the iron plaque to rice roots. In rice, S addition inhibited Cd transfer from the rice roots to the straw;thus, more Cd was stored in the rice roots. Nevertheless, additional S application increased the Cd content in the rice grains by 72% under discontinuous flooding, although this effect was mitigated by continued flooding. Under simulated practical water management conditions, S addition increased the risk of Cd contamination in rice, suggesting that S application should be reconsidered as a paddy fertilization strategy.

关键词： Rice Cadmium Sulfur Water management Iron plaque Accumulation

FACE RECOGNITION BASED ON WAVELET-CURVELET-FRACTAL TECHNIQUE

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Journal of Electronics(China) 2010年第2期27卷 206-211页

作者： Zhang zhong zhuang Peidong Liu Yong Ding Qun Ye Hong＇an Department of Electronic Engineering Heilongjiang University Harbin 150080 China

In this paper,a novel face recognition method,named as wavelet-curvelet-fractal technique,is proposed. Based on the similarities embedded in the images,we propose to utilize the wave-let-curvelet-fractal technique to extract facial features. Thus we have the wavelet’s details in diagonal,vertical,and horizontal directions,and the eight curvelet details at different angles. Then we adopt the Euclidean minimum distance classifier to recognize different faces. Extensive comparison tests on dif-ferent data sets are carried out,and higher recognition rate is obtained by the proposed technique.

关键词： Face recognition Wavelet decomposition Curvelet transform Fractal Facial feature extraction

Experimental study on nanosecond pulsed pin-to-plate discharge in supersonic air flow

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Plasma Science and Technology 2019年第9期21卷 122-131页

作者： Yiwen LI zhong zhuang Lei PANG Pengzhen DUAN Zhiwen DING Bailing ZHANG Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University Xi'an 710038 People's Republic of China Science and Technology on Combustion Internal Flow and Thermo-Structure Laboratory Astronautics School Northwestern Polytechnical University Xi'an 710072 People's Republic of China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an 710049 People's Republic of China

Development of magnetohydrodynamic acceleration technology is expected to improve wind tunnel simulation capability and testing *** underlying premise is to produce uniform and stable plasma in supersonic air flow,and gas discharge is an effective way to achieve this.A nanosecond pulsed discharge experimental system under supersonic conditions was established,and a pin-to-plate nanosecond pulsed discharge experiment in Mach 2 air flow was performed to verify that the proposed method produced uniform and stable plasma under supersonic *** results show that the discharge under supersonic conditions was stable overall,but uniformity was not as good as that under static *** the number of pins improved discharge uniformity,but reduced discharge intensity and hence plasma *** multi-pin conditions at 1000Hz,the discharge was almost completely corona discharge,with the main current component being the displacement current,which was smaller than that under static conditions.

关键词： nanosecond pulse discharge supersonic air flow pin-to-plate discharge plasma uniform and stable

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