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Two-Dimensional Parabolic Inverse Source Problem with Final Overdetermination in Reproducing Kernel Space

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Chinese Annals of Mathematics,Series B 2014年第3期35卷 469-482页

作者： wenyan wang Masahiro YAMAMOTO Bo HAN Department of Mathematics Harbin Institute of Technology Department ofMathematics Northeast Forestry University Graduate School of Mathematical Sciences The University of Tokyo

A new method of the reproducing kernel Hilbert space is applied to a twodimensional parabolic inverse source problem with the final overdetermination. The exact and approximate solutions are both obtained in a reproducing kernel space. The approximate solution and its partial derivatives are proved to converge to the exact solution and its partial derivatives, respectively. A technique is proposed to improve some existing methods. Numerical results show that the method is of high precision, and confirm the robustness of our method for reconstructing source parameter.

关键词： Inverse source problem Final overdetermination Parabolic equation Reproducing kernel

Basic helix-loop-helix(bHLH)transcription factor MdbHLH3 negatively affects the storage performance of postharvest apple fruit

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Horticultural Plant Journal 2022年第6期8卷 700-712页

作者： wenyan wang Jianqiang Yu Mengchi Du Jiahui wang Dagang Hu National Key Laboratory of Crop Biology MOA Key Laboratory of Horticultural Crop Biology and Germplasm InnovationShandong Collaborative Innovation Center for Fruit and Vegetable Production with High Quality and EfficiencyCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China College of Horticulture and Plant Protection Yangzhou UniversityYangzhou225009China

The storage period of fleshy fruits greatly affects their quality and selection,and is largely controlled by genetic ***,it is imperative to elucidate how genetic factors affect fruit ripening and its ***,we evaluated the postharvest storage properties of the basic helix-loop-helix(bHLH)transcription factor MdbHLH3-overexpressing transgenic Royal gala apple *** storage,the contents of starch,malic acid,fructose,glucose,and sucrose in fruits of three MdbHLH3 transgenic lines were always higher than those of the wild-type(WT)***,the sugar-acid ratio also showed the same trend during fruit ***,the fruit firmness decreased with increasing storage time,and the contents of cell wall components such as water-soluble pectin and cellulose in transgenic fruits were higher than those in control fruits,while the firmness of transgenic fruits was lower than that in WT control *** the ethylene release rate in both showed the same trend(firstly increasing,then decreasing,and finally peaking)in 90-day stored fruits,transgenic apples had higher ethylene levels than the WT control throughout ***,the activities of membrane peroxidase,antioxidant enzymes,and fruit ripening enzymes in all transgenic fruits were significantly higher than those in the WT ***,our findings show how MdbHLH3 negatively regulates and reduces apple storage *** may prove useful for not only developing biotechnological strategies,but also support traditional breeding programs,to help improve the storage time of fleshy fruits.

关键词： Apple MdbHLH3 Postharvest storage Firmness Ethylene Enzyme activity

Preparation and magnetic properties of Fe_2O_3 microtubules prepared by sol-gel template method

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Rare Metals 2010年第5期29卷 501-504页

作者： CHANG Chuanbo ZHANG Cunrui wang wenyan LI Qiaoling Department of Chemistry North University of China Taiyuan 030051 China School of Chemical Engineering andEnvironment North University of China Taiyuan 030051 China

Fe（OH）3 precursor sol was prepared by a sol-gel method. The precursor sol was dipped onto the absorbent cotton, and gel was formed on the absorbent cotton template after the volatilization of moisture. Fe2O3 microtubules were synthesized after the process of self-propagation or calcination. The phase, morphology, and particle diameter of the samples were examined by X-ray diffraction （XRD） and scanning electron microscopy （SEM）, and the magnetic properties of the samples were measured using a vibrating sample magnetometer （VSM）. The external diameters of Fe2O3 microtubules ranged between 8 and 13 μm, and the wall thicknesses ranged between 0.5 and 2 μm. The type of the calcination method plays a significant role in developing the Fe2O3 phase and the variation in the magnetic properties in the sol-gel template complexing method. γ-Fe2O3 was synthesized by a self-propagation method. However, α-Fe203 was synthesized after calcination at 400℃ for 2 h. The coercivity of the samples synthesized by calcination at 400℃ for 2 h after self-propagation was found to increase significantly, thereby presenting hard magnetic properties.

关键词： inorganic compounds iron oxides microtubules sol-gel process magnetic properties

Contact Resistance and Arc Erosion of Tungsten-copper Contacts in Direct Currents

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 816-822页

作者：马窦琴 XIE Jingpei LI Jiwen wang Aiqin wang wenyan School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471023 China Non-ferrous Metal Generic Technology Collaborative Innovation Center of Henan Province Luoyang 471023 China

The arc erosion under medium direct currents in the argon flow was tested on tungsten-copper（W-Cu） contacts which were processed by hot extrusion and heat treatment. The scanning electron microscopy（SEM） and transmission electron microscopy（TEM） were used to study the microstructure of the W-Cu powders and compacts. The contact resistance, arcing energy, and arcing time were continuously measured by JF04C contact materials test system. Changes in tungsten-copper contact surface were observed by SEM. The test results showed that the arcing time and arcing energy all increase with current and voltage, but the changes of average contact resistance are more complicated. For a short arcing time, the average contact resistance decreases with increasing current due to the vaporization of Cu. However, for a longer arcing time, it slightly increases due to the formation of high resistant films, compound copper tungsten. The formation of compound copper tungsten was confirmed by the increased Rc kept in the range from 1.1 to 1.6 mΩ. The compound copper tungsten is first exposed with a tungsten and copper-rich surface, and then totally exposed due to evaporation of copper from the surface. At last a stabilized surface is created and the crystals decrease from 8 μm to 2 μm caused by the arc erosion.

关键词： Tungsten-copper contacts arc erosion contact resistance surface analysis

Spatial impacts of climate factors on regional agricultural and forestry biomass resources in north-eastern province of China

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Frontiers of Environmental Science & Engineering 2016年第4期10卷 91-104页

作者： wenyan wang Wei Ouyang Fanghua Hao Yun Luan Bo Hu School of Environment State Key Laboratory of Water Environment Simulation Beijing Normal University Beijing 100875 China Beijing Zhongchi Green Energy and Environmental Technology Co. Ltd. Golden Resources Office Building Beijing 100097 China The Administrative Center for China's Agenda 21 Ministry of Science and Technology of the People's Republic of China Beijing 100038 China Department of Soil and Water Conservation Changjiang River Scientific Research Institute Wuhan 430019 China

The dynamics of agricultural and forestry biomass are highly sensitive to climate change, particularly in high latitude regions. Heilongjiang Province was selected as research area in North-east China. We explored the trend of regional climate warming and distribution feature of biomass resources, and then analyzed on the spatial relationship between climate factors and biomass resources. Net primary productivity （NPP） is one of the key indicators of vegetation productivity, and was simulated as base data to calculate the distribution of agricultural and forestry biomass. The results show that temperatures rose by up to 0.37℃/10a from 1961 to 2013. Spatially, the variation of agricultural biomass per unit area changed from -1.93 to 5.85 ***^-2.a^-1 during 2000,2013. More than 85% of farmland areas showed a positive relationship *** agricultural biomass and precipitation. The results suggest that precipitation exerts an overwhelming climate influence on agricultural biomass. The mean density of forestry biomass varied from 10 to 30 t·km^-2. Temperature had a significant negative effect on forestry biomass in Lesser Khingan and northern Changbai Mountain, because increased temperature leads to decreased Rubisco activity and increased respiration in these areas. Precipitation had a significant positive relationship with forestry biomass in south-western Changbai Mountain, because this area had a wanner climate and stress from insufficient precipitation may induce xylem cavitation. Understanding the effects of climate factors on regional biomass resources is of great significance in improving environmental management and promoting sustainable development of further biomass resource use.

关键词： Biomass resourcesNet primary productivity (NPP)Climate change Heilongjiang Province China

Overexpression of GhPFN2 enhances protection against Verticillium dahliae invasion in cotton

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Science China(Life Sciences) 2017年第8期60卷 861-867页

作者： wenyan wang Yongduo Sun Libo Han Lei Su Ouixian Xia Haiyun wang Institute of Microbiology Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Plant Genomics Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Growing evidence indicates that actin cytoskeleton is involved in plant innate immune responses, but the functional mechanism remains largely unknown. Here, we investigated the behavior of a cotton profilin gene （GhPFN2） in response to Verticillium dahliae invasion, and evaluated its contribution to plant defense against this soil-borne fungal pathogen. GhPFN2 expression was up-regulated when cotton root was inoculated with V. dahliae, and the actin architecture was reorganized in the infected root cells, with a clear increase in the density of filamentous actin and the extent of actin btmdling. Compared to the wild type, GhPFN2-overexpressing cotton plants showed enhanced protection against V. dahliae infection and the actin cytoskeleton organization in root epidermal cells was clearly altered, which phenocopied that of the wild-type （WT） root cells challenged with V. dahliae. These results provide a solid line of evidence important for defense against V. dahliae infection. showing that actin cytoskeleton reorganization involving GhPFN2 is

关键词： actin cytoskeleton profilin Verticillium dahliae cotton

Thermal Expansion and Mechanical Properties of Middle Reinforcement Content SiCp/Al Composites Fabricated by PM Technology

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Journal of Wuhan University of Technology(Materials Science) 2014年第4期29卷 660-664页

作者：郝世明谢敬佩 wang Aiqin wang wenyan LI Jiwen SUN Haoliang Physical Engineering College and Laboratory of Materials Physics of the Ministry of Education of China Zhengzhou University School of physics and engineering Henan University of Science and Technology College of Materials Science and Engineering Henan University of Science and Technology

Middle reinforcement content SiCp/Al composites（Vp=30%, 35% and 40%） for precision optical systems applications were fabricated by powder metallurgy technology. The composites were free of porosity and SiC particles distributed uniformly in the composites. The mean linear coefficients of thermal expansion（20-100 ℃） of SiCp/Al composites ranged from 11.6×10-6 to 13.3×10-6 K-1 and decreased with an increase in volume fraction of SiC content. The experimental coeffi cients of thermal expansion agreed well with predicted values based on Kerner＇s model. The Brinell hardness increased from 116 to 147, and the modulus increased from 99 to 112 GPa for the corresponding composites. The tensile strengths were higher than 320 MPa, but no signifi cant increasing trend between tensile strength and SiC content was observed.

关键词： metal-matrix composites particle-reinforcement coefficient of thermal expansion mechanical properties powder metallurgy

Influence of Different Al Contents on Microstructure, Tensile and Wear Properties of Zn-based Alloy

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Journal of Materials Science & Technology 2010年第7期26卷 648-652页

作者： Shuqing Yan Jingpei Xie Zhongxia Liu wenyan wang Aiqin Wan Jiwen Li Department of Physics and Laboratory of Materials Physics of the Ministry of Education of China Zhengzhou University Zhengzhou 450052 China College of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003 China

The influence of different Al contents on the microstructure, hardness, tensile and wear behavior of Zn-based alloys was investigated in the present study. The test results show that alloy with 27% Al content shows the higher ultimate strength and elongation percent at room and elevated temperatures. It also exhibits the higher wear resistance at all loads in view of the higher tightness of Zn-27Al alloy. Increasing Al content from 33% to 48% results in improvement of ultimate strength and elongation percent at room and elevated temperatures. However, the ultimate strength and elongation percent of the ZA48 alloy are still lower than that of Zn-27Al alloys. The reason can be attributed to the increasing segregation and voids with increasing Al contents.

关键词： Zinc-based alloys Mechanical property Wear property

Multimodal Medical Image Fusion Based on Parameter Adaptive PCNN and Latent Low-rank Representation

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Instrumentation 2023年第1期10卷 45-58页

作者： wang wenyan ZHOU Xianchun YANG Liangjian Nanjing University of Information Science and Technology Nanjing 210044

Medical image fusion has been developed as an efficient assistive technology in various clinical applications such as medical diagnosis and treatment *** at the problem of insufficient protection of image contour and detail information by traditional image fusion methods,a new multimodal medical image fusion method is *** method first uses non-subsampled shearlet transform to decompose the source image to obtain high and low frequency subband coefficients,then uses the latent low rank representation algorithm to fuse the low frequency subband coefficients,and applies the improved PAPCNN algorithm to fuse the high frequency subband ***,based on the automatic setting of parameters,the optimization method configuration of the time decay factorαe is carried *** experimental results show that the proposed method solves the problems of difficult parameter setting and insufficient detail protection ability in traditional PCNN algorithm fusion images,and at the same time,it has achieved great improvement in visual quality and objective evaluation indicators.

关键词： Image Fusion Non-subsampled Shearlet Transform Parameter Adaptive PCNN Latent Low-rank Representation