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Inclusions for Ultra-pure Ferritic Stainless Steels Containing 21% Chromium

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Journal of Iron and Steel Research International 2013年第10期20卷 70-74页

作者： WANG hong-po SUN Li-feng PENG Bo JIANG Mao-fa College of Materials and Metallurgy Northeastern University

As stabilizing elements added into ultra-pure ferritic stainless steels, niobium and titanium react with car- bon and nitrogen to form carbonitrides and have great effects on the ratio of equiaxed zone and the grain size of solidi- fication structure of ingots, which remarkably affect the quality of cold-rolled sheets. Combined with thermodynamic calculation, style and precipitation progress of inclusions in ultra-pure ferritic stainless steels were investigated by optical microscopy, scanning electron microscopy, transmission electron microscopy and energy dispersive spectros- copy. The results indicate that the inclusions are mainly Ti-Al-N- O system inclusions in ultra-pure ferritic stainless steels. Al2Oa starts to precipitate firstly and then TiOx and TiN precipitates sequently. The inclusions are mainly single TiN particles and complex inclusions with Al2O3-Ti2O3 as cores and covered with TiN under the condition of 0.31% titanium addition and mainly Al2O3 under the condition of 0.01% titanium addition. A few （Nb,Ti）N parti- cles precipitate because of no enough titanium to react with nitrogen when titanium addition is 0.01 %. In addition, fine Nb（C, N） particles with size of less than 500 nm precipitate at relatively low temperature.

关键词： ultra-pure ferritic stainless steel ingot inclusion stabilizing element

Inclusions and solidification structures of high pure ferritic stainless steels dual stabilized by niobium and titanium

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Rare Metals 2014年第6期33卷 761-766页

作者： hong-po Wang Li-Feng Sun Jun-Jie Shi Cheng-Jun Liu Mao-Fa Jiang Chi Zhang Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Northeastern University

As the raw materials in the post process of rolling and heat treatment, ingots have great effects on the properties of the final products. Inclusions and solidification structures are the most important aspects of the quality of ingots. Niobium and titanium are usually used to react with carbon and nitrogen to improve the properties of ferritic stainless steels. In this research, combined with thermodynamic calculation, effects of niobium and titanium on the inclusions and solidification structures in three kinds of high pure ferritic stainless steels with different titanium additions were investigated by optical microscope（OM）, scanning electron microscope（SEM）, transmission electron microscope（TEM）, and energy disperse spectrometer（EDS）. Results show that Al2O3 and a few（Nb,Ti）N particles form when titanium addition is 0.01 %.Furthermore, inclusions are mainly Ti N and Al2O3–Ti Ox–Ti N duplex inclusions when titanium addition is more than0.10 %. Those two types of inclusions are in well distribution, and can afford nuclei to the solidification ***, the ratio of equiaxed zone increases with the increase of titanium addition. The ratio increases from42.1 % to 64.0 % with the titanium addition increasing from 0.01 % to 0.10 %, and it increases to 85.7 % when the titanium addition reaches 0.34 %.

关键词： High pure ferritic stainless steel Inclusion Solidification structure Equiaxed zone Stabilization element

Synthesis, Characterization and Biological Activities of N-Acyl-3-（3-pyridyl）-5-aryl-pyrazoles

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Chemical Research in Chinese Universities 2013年第2期29卷 227-230页

作者： KANG Yan-fang WANG Dun-jia XU Ben-po WEI Xian-hong ZHENG Jing Hubei Provincial Key Laboratory of pollutant Analysis and Reuse Technology College of Chemistry and Environmental Engineering Hubei Normal University Huangshi 435002 P. R. China

Ten novel N-acyl-3-（3-pyridyl）-5-aryl-pyrazoles were synthesized by Claisen condensation of the aryl methyl ketones with ethyl nicotinate, the cyclization with hydrazine hydrate and the N-acylation with acyl chloride in turn. The structures of all the compounds synthesized were confirmed by means of Fourier transform infrared（FTIR）, IH NMR, mass spectroscopy and elemental analysis. The biological activities of the title compounds were examined by disc diffusion method against Escherichia coil Staphylococcus aureus, Pyricularia oryzae and Rhizoctnia solani. All the N-acyl-3-（3-pyridyl）-5-aryl-pyrazoles exhibited a certain degree of antibacterial and antifungal activities. Comparatively, compounds 3c and 3d exhibited much significant antibacterial and antifungal activities than the other pyrazole derivatives.

关键词： N-Acyl-3-(3-pyridyl)-5-aryl-pyrazole fl-Diketone 1H-Pyrazole Biological activity

Stability and Hopf Bifurcation of the Maglev System with Delayed Speed Feedback Control

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自动化学报 2007年第8期33卷 829-834页

作者： WANG hong-po LI Jie ZHANG Kun School of Meehatronics and Automation National University ofDefense Technology Changsha 410073 P. R. China

Abstract The problem of time delay speed feedback in the control loop is considered here. Its effects on the linear stability and dynamic behavior of the maglev system are investigated. It is found that a Hopf bifurcation can take place when the time delay exceeds certain values. The stability condition of the maglev system with the time delay is acquired. The direction and stability of the Hopf bifurcation are determined by constructing a center manifold and by applying the normal form method. Finally, numerical simulations are performed to verify the analytical result.

关键词：延时反馈控制稳定性磁力悬浮火车系统霍普夫分岔规格化形式

Phosphorus forms and distribution in Zhejiang coastal sediment in the East China Sea

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International Journal of Sediment Research 2014年第2期29卷 278-284页

作者： Min CONG Tao JIANG Yu-zao QI hong-po DONG De-qiang TENG Song-hui LU Research Center for Harmful Algae and Marine Biology Jinan University Journal Editorial Department Jinan University Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Sciences Research Center for Harmful Algae and Marine Biology/Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes Jinan University Guangzhou Marine Geological Survey

Surface and core sediment samples were collected from Zhejiang coastal waters of the East China Sea to study phosphorus（P） forms and understand the potential release of P as well as *** sediments were extracted sequentially to determine four phosphorus fractions,and non-sequentially for total phosphorus（TP）.The total concentration of phosphorus in the surface sediments ranged from 527.2 to 680.5 mg kg;.Inorganic P was the major form and accounted for 84-94%of *** the four forms,P-Detrital was dominant（58.6-73.2%）,followed by P-CDB（10.5-20.9%）,P-Organic（6.1-15.9%）,and P-CFA（5.9-16.3%）.The distribution pattern of TP in the surface sediments was similar to that of P-Detrital and P-Organic,but different from P-CDB and P-CFA.A relatively high level of phosphorus was observed in estuarine sediments,reflecting the influence from terrestrial *** in all forms in core sediments at each station decreased with *** addition,potentially bio-available phosphorus accounted for 20-34%of TP.

关键词： Phosphorus forms Distribution Sediment Zhejiang coastal waters East China Sea

MFCIS: an automatic leaf-based identification pipeline for plant cultivars using deep learning and persistent homology

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Horticulture Research 2021年第1期8卷 2361-2374页

作者： Yanping Zhang Jing Peng Xiaohui Yuan Lisi Zhang Dongzi Zhu po hong Jiawei Wang Qingzhong Liu Weizhen Liu School of Computer Science and Technology Wuhan University of TechnologyWuhanHubeiChina Chongqing Research Institute Wuhan University of TechnologyChongqingChina Shandong Key Laboratory of Fruit Biotechnology Breeding Shandong Institute of PomologyTaianShandongChina

Recognizing plant cultivars reliably and efficiently can benefit plant breeders in terms of property rights protection and innovation of germplasm *** leaf image-based methods have been widely adopted in plant species identification,they seldom have been applied in cultivar identification due to the high similarity of leaves among ***,we propose an automatic leaf image-based cultivar identification pipeline called MFCIS(Multi-feature Combined Cultivar Identification System),which combines multiple leaf morphological features collected by persistent homology and a convolutional neural network(CNN).Persistent homology,a multiscale and robust method,was employed to extract the topological signatures of leaf shape,texture,and venation details.A CNN-based algorithm,the Xception network,was fine-tuned for extracting high-level leaf image *** fruit species,we benchmarked the MFCIS pipeline on a sweet cherry(Prunus avium L.)leaf dataset with>5000 leaf images from 88 varieties or unreleased selections and achieved a mean accuracy of 83.52%.For annual crop species,we applied the MFCIS pipeline to a soybean(Glycine max ***.)leaf dataset with 5000 leaf images of 100 cultivars or elite breeding lines collected at five growth *** identification models for each growth period were trained independently,and their results were combined using a score-level fusion *** classification accuracy after score-level fusion was 91.4%,which is much higher than the accuracy when utilizing each growth period independently or mixing all growth *** facilitate the adoption of the proposed pipelines,we constructed a user-friendly web service,which is freely available at http://***.

关键词： MFC network identification

一类非自治位置时滞反馈控制系统的亚谐共振响应

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物理学报 2007年第5期56卷 2504-2516页

作者：王洪坡李杰长沙国防科学技术大学机电工程与自动化学院磁浮工程中心长沙410073

研究了弹性轨道条件下,控制回路中位置反馈信号存在时滞的磁浮系统在亚谐轨道激励作用下的响应问题.将动力学模型在平衡点处线性化,以时滞为分岔参数,得到了系统出现Hopf分岔的条件.用中心流形约化方法得到了包含轨道扰动系统的poincar... 详细信息

研究了弹性轨道条件下,控制回路中位置反馈信号存在时滞的磁浮系统在亚谐轨道激励作用下的响应问题.将动力学模型在平衡点处线性化,以时滞为分岔参数,得到了系统出现Hopf分岔的条件.用中心流形约化方法得到了包含轨道扰动系统的poincar啨规范型.用多尺度法从理论上推导了时滞磁浮系统的亚谐共振周期解,得到了自由振动的分岔响应方程,分析了周期解中自由振动项的存在条件,研究了控制参数和激励参数与周期解的关系.最后用数值仿真的方法分析了时滞参数、控制参数对系统响应的影响,分析结果指出,使系统保持稳定的亚谐响应的时滞边界小于无扰动时的时滞边界,时滞参数不但可以抑制亚谐响应,还能够控制混沌的产生,而控制参数可以控制系统响应中自由振动项的出现和受迫振动的幅值,适当选择这些参数可以有效抑制亚谐振动响应.

关键词：亚谐共振响应位置时滞反馈控制非自治磁浮系统分岔

Chromosome-scale genome assembly of sweet cherry(Prunus avium L.)*** obtained using long-read and Hi-C sequencing

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Horticulture Research 2020年第1期7卷 1214-1224页

作者： Jiawei Wang Weizhen Liu Dongzi Zhu po hong Shizhong Zhang Shijun Xiao Yue Tan Xin Chen Li Xu Xiaojuan Zong Lisi Zhang Hairong Wei Xiaohui Yuan Qingzhong Liu Shandong Key Laboratory of Fruit Biotechnology Breeding Shandong Institute of PomologyTaianShandong 271000China School of Computer Science and Technology Wuhan University of TechnologyWuhanHubei 430070China State Key Laboratory of Crop Biology Shandong Agricultural UniversityTaianShandong 271018China Gooal Gene WuhanHubei 430070China

Sweet cherry(Prunus avium)is an economically significant fruit species in the genus ***,in contrast to other important fruit trees in this genus,only one draft genome assembly is available for sweet cherry,which was assembled using only Illumina short-read *** incompleteness and low quality of the current sweet cherry draft genome limit its use in genetic and genomic studies.A high-quality chromosome-scale sweet cherry reference genome assembly is therefore needed.A total of 65.05 Gb of Oxford Nanopore long reads and 46.24 Gb of Illumina short reads were generated,representing~190x and 136x coverage,respectively,of the sweet cherry *** final de novo assembly resulted in a phased haplotype assembly of 344.29 Mb with a contig N50 of 3.25 ***-C scaffolding of the genome resulted in eight pseudochromosomes containing 99.59%of the bases in the assembled *** annotation revealed that more than half of the genome(59.40%)was composed of repetitive sequences,and 40,338 protein-coding genes were predicted,75.40%of which were functionally *** the chromosomescale assembly,we revealed that gene duplication events contributed to the expansion of gene families for salicylic acid/jasmonic acid carboxyl methyltransferase and ankyrin repeat-containing proteins in the genome of sweet *** auxin-responsive genes(two GH3s and two SAURs)were induced in the late stage of fruit development,indicating that auxin is crucial for the sweet cherry ripening *** addition,772 resistance genes were identified and functionally predicted in the sweet cherry *** high-quality genome assembly of sweet cherry obtained in this study will provide valuable genomic resources for sweet cherry improvement and molecular breeding.

关键词： sweet bases assembly

SiO_2/TiO_2复合薄膜光催化性能的研究

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材料工程 2008年第12期36卷 38-40,45页

作者：郭子斌赵宏生胡红坡清华大学核能与新能源技术研究院北京100084

采用溶胶-凝胶法和浸渍提拉法在玻璃表面镀制了SiO2/TiO2复合薄膜,以SEM,XPS,UV-Vis等手段对其进行了表征;通过对亚甲基蓝的降解反应,研究了SiO2/TiO2复合薄膜在紫外光下的光催化性能。结果表明:在玻璃片上预镀SiO2层使TiO2薄膜中的Na+... 详细信息

采用溶胶-凝胶法和浸渍提拉法在玻璃表面镀制了SiO2/TiO2复合薄膜,以SEM,XPS,UV-Vis等手段对其进行了表征;通过对亚甲基蓝的降解反应,研究了SiO2/TiO2复合薄膜在紫外光下的光催化性能。结果表明:在玻璃片上预镀SiO2层使TiO2薄膜中的Na+和Mg2+含量明显降低,同时,有利于TiO2薄膜中晶粒的长大,提高了光催化性能。

关键词： SiO2/TiO2复合薄膜溶胶-凝胶法光催化性能