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International Journal of Biomathematics 2012年第3期5卷 283-295页

作者： ling CHEN WANBIAO ma Department of Applied mathematics School of mathematics and Physics University of Science and Technology Beijing Beijing 100083 P. R. China Beijing Business management School Beijing 100097 P. R. China

In this paper, based on some biological meanings and a model which was proposed by Lefever and Garay （1978）, a nonlinear delay model describing the growth of tumor cells under immune surveillance against cancer is given. Then, boundedness of the solutions, local stability of the equilibria and Hopf bifurcation of the model are discussed in details. The existence of periodic solutions explains the restrictive interactions between immune surveillance and the growth of the tumor cells.

关键词： Immune surveillance differential equation time delay local asymptotic stability Hopf bifurcation.

Colour modulation and enhancement of upconversion emissions in K_(2)NaScF_(6):Yb/Ln(Ln=Er,Ho,Tm) nanocrystals

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Journal of Rare Earths 2021年第12期39卷 1477-1483,I0001页

作者： Yangbo Wang Huaiyong Li Hui ma ling Huang School of materials Science and Engineering Liaocheng UniversityLiaocheng 252059China Institute of Advanced materials Nanjing Tech UniversityNanjing 211816China

Effective colour modulation of upconversion emissions in lanthanide-doped nanomaterials becomes even more important for fundamental and applied ***,on the one hand,by raising the content of doped Yb^(3+)from 10 mol%to 50 mol%,a significant increase of the red/green emission ratio from 4.0 to 68.2 is observed in K_(2)NaScF_(6):Yb/Er *** yellow to red colour change is attributed to the increased cross relaxation between Er^(3+)and Yb^(3+)caused by the increased Yb^(3+)amount,^(4) S_(3/2)(Er^(3+))^(+2) F7/2(Yb^(3+))→4 I13/2(Er^(3+))^(+2) F5/2(Yb^(3+)).On the other hand,the upconversion green and red emission of K_(2)NaScF_(6):Yb/Er(20/2 mol%)nanocrystals are intensified 10.6 and 8.8 folds,respectively,after an active shell(K_(2)NaScF_(6):Yb)is epitaxially grown,which are more effective than the7.4-and 6.4-fold enhancement from an inert shell(K_(2)NaScF_(6))***,the shell thickness from2.85 to 9.5 nm through controlling the molar ratio of shell-precursor to core from 1:2 to 3:1 can be easily *** study will provide more opportunities for the application of K_(2)NaScF_(6):Yb/Ln nanoparticles in varied fields such as theranostics,photovoltaics,and photocatalysis.

关键词： Upconversion Emission modulation Core-shell K_(2)NaScF_(6) Rare earths

Preserving details in semantics-aware context for scene parsing

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Science China(Information Sciences) 2020年第2期63卷 79-92页

作者： Shuai ma Yanwei PANG Jing PAN ling SHAO Tianjin Key Laboratory of Brain-Inspired Intelligence Technology School of Electrical and Information EngineeringTianjin University School of Electronic Engineering Tianjin University of Technology and Education

Great success of scene parsing(also known as, semantic segmentation) has been achieved with the pipeline of fully convolutional networks(FCNs). Nevertheless, there are a lot of segmentation failures caused by large similarities between local appearances. To alleviate the problem, most of existing methods attempt to improve the global view of FCNs by introducing different contextual modules. Though the reconstructed high resolution output of these methods is of rich semantics, it cannot faithfully recover the fine image details owing to lack of desired precise low-level information. To overcome the problem, we propose to improve the spatial decoding process through embedding possibly lost low-level information in a principled way. To this end, we make the following three contributions. First, we propose a semantics conformity module to make low-level features variations agnostic. Second, we introduce semantics into the conformed low level features through guidance from semantically aware features. Finally, we institute the availability of various possible contextual features at feature fusion to enrich context information. The proposed approach demonstrates competitive performance on challenging PASCAL VOC 2012, Cityscapes,and ADE20K benchmarks in comparison to the state-of-the-art methods.

关键词： fully convolutional networks semantic segmentation cityscapes semantic-aware context

Reaction products of Sm_(2)Zr_(2)O_(7) with calcium-magnesium-aluminum-silicate(CmaS)and their evolution

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Journal of Advanced Ceramics 2021年第6期10卷 1389-1397页

作者： Yinghua WANG Zhuang ma ling LIU Yanbo LIU School of materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on materials under Shock and Impact Beijing 100081China

During flight,many silicates(sand,dust,debris,fly ash,etc.)are ingested by an *** melt at high operating temperatures on the surface of thermal barrier coatings(TBCs)to form calcium-magnesium-aluminum-silicate(CmaS)amorphous *** corrodes TBCs and causes many problems,such as composition segregation,degradation,cracking,and *** a new generation of TBC candidate materials,rare-earth zirconates(such as Sm_(2)Zr_(2)O_(7))have good CmaS resistance *** reaction products of Sm_(2)Zr_(2)O_(7) and CmaS and their subsequent changes were studied by the reaction of Sm_(2)Zr_(2)O_(7) and excess CmaS at 1350℃.After 1 h of reaction,Sm_(2)Zr_(2)O_(7) powders were not completely *** reaction products were Sm-apatite and c-Zr0_(2) solid *** 4h of reaction,all Sm_(2)Zr_(2)O_(7) powders were completely *** 24 h of reaction,Sm-apatite disappeared,and the c-Zr02 solid solution remained.

关键词： Sm_(2)Zr_(2)O_(7)ceramic calcium-magnesium-aluminum-silicate(CmaS) reaction product corrosion

Preparation and heat insulating capacity of Sm2Zr2O7-SiC composites based on photon thermal transport

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Journal of Advanced Ceramics 2020年第4期9卷 454-461页

作者： Zhuang ma Qi Zhang ling Liu Yanbo Liu School of materials Science and Engineering Beijing Institute of TechnologyBeijing100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing401120China

A series of Sm2Zr2O7-SiC composites doped with different volume fraction and particle size of SiC were prepared by hot pressing at 1300°*** phase of the composites prepared is P-Sm2Zr2O7 and C-SiC,and no other diffraction peaks exist,which indicates that Sm2Zr2O7 has great chemical compatibility with *** thermal conductivity and phonon thermal conductivity of the Sm2Zr2O7-SiC composites are measured by the laser pulse *** photon thermal conductivity of the composites is obtained by subtracting the phonon thermal conductivity from the total thermal *** results show that the photon thermal conductivity of Sm2Zr2O7-SiC composites is lower than that of pure *** photon thermal conductivity of Sm2Zr2O7-SiC composites decreases first and then increases with the increase of SiC particle ***2Zr2O7-(5 vol%,10µm)SiC composite has the lowest photon thermal conductivity.

关键词： rare-earth zirconates thermal conductivity photon thermal transport

Blind identification of space–time block codes based on deep learning

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Chinese Journal of Aeronautics 2022年第1期35卷 426-435页

作者： Limin ZHANG Yuyuan ZHANG Wenjun YAN ling ma Institute of Information Fusion Naval Aeronautical UniversityYantai 264001China Coastal Defense College Naval Aeronautical UniversityYantai 264001China

Deep Learning(DL)has important applications to both commercial and military communications,such as software-defined radio,cognitive radio and spectrum *** DL has been intensively studied for modulation recognition,there are very few investigations for blind identification of Space-Time Block Codes(STBCs).This paper proposes a Residual Network(RN)-based model for identifying 6 kinds of STBC signals with a single receiving antenna,including the same length of coding *** our work,we use the frequency-domain correlation function of a single time delay as the training data of DL ***,we explore the suitable RN structure for blind identification of ***,we compare the RN model with convolutional neural network and traditional method,and test the performance of RN *** results show that our RN-based model provides good performance with low sensitivity to decay of the dataset,such as sample length and data *** the same time,better identification accuracy can be achieved under the condition of different modulation types and channel fading parameters at low Signal to Noise Ratio(SNR).

关键词： Blind identification Deep learning Multiple-input multiple-output Residul network Space-time block code

基于深度学习的甘蓝叶片超氧化物歧化酶活性模型构建

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安徽农业科学 2025年第1期53卷 229-235页

作者：马思艳马玲马燕王静张祎洋吴龙国宁夏大学葡萄酒与园艺学院宁夏银川750021 宁夏现代设施园艺工程技术研究中心宁夏银川750021

超氧化物歧化酶(SOD)是判断作物受胁迫程度的关键指标,可以用来衡量植物生长状况,同时也在植物逆境胁迫研究中具有重要意义。为了实现甘蓝叶片SOD活性的快速无损检测,提出了一种利用高光谱成像技术结合深度学习的方法来对甘蓝叶片进行... 详细信息

超氧化物歧化酶(SOD)是判断作物受胁迫程度的关键指标,可以用来衡量植物生长状况,同时也在植物逆境胁迫研究中具有重要意义。为了实现甘蓝叶片SOD活性的快速无损检测,提出了一种利用高光谱成像技术结合深度学习的方法来对甘蓝叶片进行检测。试验共采集了200片甘蓝叶片在不同生长发育时期的光谱信息,通过7种预处理方法对原始光谱进行优化,最后选用高斯滤波方法为SOD活性的预处理方法。采用连续投影算法、无信息变量消除算法、遗传偏最小二乘算法、竞争自适应重加权采样算法和区间变量迭代空间收缩分析算法提取特征波长,建立偏最小二乘回归模型。基于优选的特征波长建立PLSR、主成分回归、多元线性回归、最小二乘支持向量机和深度学习模型。结果表明,CARS算法提取的17个最佳波长效果较好,最优预测模型CNN的相关系数R c和R p值分别为0.9098和0.8235,均方根误差RMSEC和RMSEP分别为2.0382和3.6492。该研究为今后盐胁迫下植株长势在线无损监测提供技术支撑,具有良好的发展前景。

关键词：高光谱成像深度学习 SOD活性无损检测

小麦TaPBF3-5D的基因克隆及生物信息学分析

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麦类作物学报 2025年第2期45卷 141-148页

作者：邓云颢李鲁华徐灵王忠妮洪鼎立邰成江徐如宏贵州大学农学院贵州贵阳550025 国家小麦改良中心贵州分中心贵州贵阳550025 贵州省农业科学院水稻研究所贵州贵阳550025

PBF因子是小麦胚乳特异基因表达调控蛋白因子之一,在调控小麦种子贮藏蛋白基因表达方面有着重要作用。本研究以小麦种质ZY96-3为材料,利用RT-PCR技术克隆获得TaPBF3-5D的CDS序列,对其进行了生物信息学和基因表达分析。结果表明,TaPBF3-5... 详细信息

PBF因子是小麦胚乳特异基因表达调控蛋白因子之一,在调控小麦种子贮藏蛋白基因表达方面有着重要作用。本研究以小麦种质ZY96-3为材料,利用RT-PCR技术克隆获得TaPBF3-5D的CDS序列,对其进行了生物信息学和基因表达分析。结果表明,TaPBF3-5D基因CDS序列共有909 bp,编码302个氨基酸;其编码的蛋白为一个非跨膜的不稳定性亲水蛋白,无信号肽,共含36个磷酸位点;预测其定位于细胞核;通过系统进化树以及多重序列比对,TaPBF3-5D与来自于普通小麦中国春的PBF在亲缘性上更为接近。经荧光定量分析,TaPBF3-5D基因在根、茎、叶和籽粒中均有表达,以籽粒中表达最高,其次是叶和茎,根中表达最低。这进一步说明TaPBF3-5D基因参与调控小麦籽粒贮藏蛋白基因表达,调节籽粒发育。

关键词： ZY96-3 TaPBF3-5D 生物信息学基因克隆

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A Novel Photoproduct of Thymine in Phosphate-buffered Saline under Far UV Irradiation

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Chinese Chemical Letters 2003年第12期14卷 1233-1235页

作者： Feng LIN Qing ling ma Department of Chemistry Xi-xi CampusZhejiang UniversityHangzhou 310028

The photolysis of thymine in phosphate-buffered saline (PBS, pH 8.0) under the irradiation of medium pressure mercury lamp (MPML) produces a novel compound C5H7N2O6P. The composition and structure of the compound hav... 详细信息

关键词： UV photolysis thymine phosphate-buffered saline (PBS).

Effects of long-term organic fertilization on soil microbiologic characteristics,yield and sustainable production of winter wheat

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Journal of Integrative Agriculture 2018年第1期17卷 210-219页

作者： LI Chun-xi ma Shou-chen SHAO Yun ma Shou-tian ZHANG ling-ling College of Life Science Henan Normal University Field Scientific Observation and Research Base of Land Use Ministry of Land and Resources/Henan Polytechnic University

We investigated the soil microbiologic characteristics, and the yield and sustainable production of winter wheat, by conducting a long-term fertilization experiment. A single application of N, P and K （NPK） fertilizer was taken as the control （CK） and three organic fertilization treatments were used： NPK fertilizer＋pig manure （T1）, NPK fertilizer＋straw return （T2）, NPK fertilizer＋pig manure＋straw return （T3）. The results showed that all three organic fertilization treatments （T1, T2 and T3） significantly increased both soil total N （STN） and soil organic carbon （SOC） from 2008 onwards. In 2016, the SOC content and soil C/N ratios for T1, T2 and T3 were significantly higher than those for CK. The three organic fertilization treatments increased soil microbial activity. In 2016, the activity of urease （sucrase） and the soil respiration rate （SRS） for T1, T2 and T3 were significantly higher than those under CK. The organic fertilization treatments also increased the content of soil microbial biomass carbon （SMBC） and microbial biomass nitrogen （SMBN）, the SMBC/SMBN ratio and the microbial quotient （qMB）. The yield for T1, T2 and T3 was significantly higher than that of CK, respectively. Over the nine years of the investigation, the average yield increased by 9.9, 13.2 and 17.4% for T1, T2 and T3, respectively, compared to the initial yield for each treatment, whereas the average yield of CK over the same period was reduced by 6.5%. T1, T2, and T3 lowered the coefficient of variation （CV） of wheat yield and increased the sustainable yield index （SYI）. Wheat grain yield was significantly positively correlated with each of the soil microbial properties （P〈0.01）. These results showed that the long-term application of combined organic and chemical fertilizers can stabilize crop yield and make it more sustainable by improving the properties of the soil.

关键词： winter wheat long-term organic fertilization soil microbial features yield stability yield sustainability