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Normality and Quasinormality of Zero-free Meromorphic Functions

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Acta Mathematica Sinica,English Series 2012年第4期28卷 707-716页

作者： jian Ming chang changshu Institute of Technology Department of Mathematics

Let k, K ∈1N and F be a family of zero-free meromorphic functions in a domain D such that for each f ∈ F, f（k） - 1 has at most K zeros, ignoring multiplicity. Then F is quasinormal of order at most v=k/k＋1,where v is equal to the largest integer not exceeding k/k＋*** particular, if K = k, then F is normal. The results are sharp.

关键词： Meromorphic functions normal family

Phase selection and microstructure evolution within eutectic Ti-Si alloy solidified at containerless state

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Science China(Technological Sciences) 2022年第7期65卷 1587-1598页

作者： LUO ZhiCong chang jian WANG HaiPeng School of Physical Science and Technology Northwestern Polytechnical UniversityXi'an 710072China

Phase selection and microstructure evolution of the undercooled eutectic Ti-Si alloy were systematically investigated by the electromagnetic levitation method, and the maximum undercooling achieved was 318 K(0.2 TE). The migration of the liquidsolid interface was in-situ detected by a high-speed camera system. When the undercooling is smaller than 140 K, the liquid-solid interface is smooth. Once the undercooling arrives at 230 K, the liquid-solid interface is irregular, which reflects the growth transition from the solute control to the combined controls of solute and thermal. The eutectic growth velocity increases as an exponential function of undercooling. The electromagnetic stirring effect makes it difficult to increase undercooling, but plays an important role in accelerating the eutectic reaction velocity at low and moderate undercoolings. Primary dendritic β-Ti phase appears in the solidified alloy from 63 to 176 K undercoolings, and the microstructure is completely composed of eutectic once the undercoolings increase up to 230 K. When the undercoolings exceed 273 K, the microstructure consists of uniformly distributed irregular eutectic. For the drop tube experiments, the microstructures composed of a large amount of dendritic α-Ti phase and eutectic phase are found in a wide range of diameters from 69 to 725 μm. As the decrease of diameter, the solubility of Si in the dendritic α-Ti phase dramatically increases from 6.80% to 10.73%, and the ratio of the area occupied by the dendritic α-Ti on a cross-section of solidified alloy obviously increases from 23.52% to 41.02%, which result from the combined effects of high undercooling and large cooling rate.

关键词： phase selection microstructure evolution high undercooling containerless large cooling rate

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Spectroscopic Properties of Sr 5p_(1/2)ns Autoionizing States

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Chinese Physics Letters 1996年第8期13卷 579-582页

作者： DAI chang-jian LÜJun Department of Physics Zhejiang UniversityHangzhou 310027

The resonance profile of the Sr 5p_(1/2)ns states and angular dependence of ejected electrons have been studied by using three-step excitation *** levels and widths of the 5p_(1/2)ns states with n ranging from 7 to 10 are *** electrons originated from the decays to different ionic states are resolved with the time-of-flight detector.

关键词： scheme states

Synthesis and Characterization of Zirconia Nanocrystallites by Cationic Surfactant and Anionic Surfactant

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1133-1139页

作者： YU jian-chang HU Sheng-Wei College of Material Science and Engineering Fuzhou University Fuzhou 350002 China

Study on nanomaterials has attracted great interests in recent years. In this article, zirconia nanocrystallites of different structures have been successfully synthesized via hydrothermal methods with cationic surfactant （CTAB） and anionic surfactant （SDS）, respectively. Differential Scanning Calorimeter （DSC-TG）, X-ray Diffractometer （XRD）, Transmission Electron Microscope （TEM）, Ultraviolet-Visible （UV-vis） and N2 adsorption-desorption analyses are used for their structure characteristics. The results show that the cationic surfactant has a distinctive direction effect on the formation of zirconia nanocrystallites, while the anionic surfactant has a self-assembly synergistic effect on them. The sample synthesized with the cationic surfactant presents good dispersion with the main phase of tetragonal zirconia, and the average nanocrystal size is around 15 nm after calcination at 500 ℃. While the sample synthesized with the anionic surfactant exhibits a worm-like mesoporous structure with pure tetragonal phase after calcination at 500 ℃ and with good thermal stability.

关键词： cationic surfactant anionic surfactant zirconia nanocrystallites,mesoporous zirconia

Hydrothermal Synthesis and Structure Analysis of Indium Vanadate (InVO_4)

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1242-1248页

作者： HUANG Qing-Ming YU jian-chang Instrumentation Analysis and Research Center Fuzhou University Fuzhou Fujian 350002 China Material science and engineering department Fuzhou University Fuzhou Fujian 350002 China

In this article, hydrothermal process is applied to synthesize nanometer InVO4. Influences of different experimental conditions （including mixing ratio of raw materials, reaction temperature, reaction time and so on） upon the synthetic products＇ purity and crystallite size are discussed to determine the best synthetic condition. The structure of nanometer InVO4 is analyzed, which helps to further understand the structure characteristics of InVO4 synthesized by applying hydrothermal process and lays foundation for further research.

关键词： hydrothermal process InVO4 experimental conditions structure

Transcriptome analysis in the beet webworm, Spoladea recurvalis （Lepidoptera： Crambidae）

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Insect Science 2018年第1期25卷 33-44页

作者： jian-Cheng chang Srinivasan Ramasamy A VRDC - The World Vegetable Center Shanhua Tainan Taiwan China

The beet webworm, Spoladea recurvalis Fabricius, is a destructive pest on vegetable crops in tropics and subtropics; its main host plant is amaranth. It has become imperative to develop non-chemical methods to control S. recurvalis on amaranth. However, the lack of molecular information about this species has hindered the development of novel pest management strategies. In this study, high-throughput RNA sequencing covering de novo sequence assemblies, functional annotation of transcripts, gene function classification and enrichment was performed on S. recurvalis. Illumina sequencing generated a total of 120 435 transcript contigs ranging from 201 to 22 729 bases with a mean length of 688 bases. The assembled transcripts were subjected to Basic Local Alignment Search Tool- X （BLASTX） to obtain the annotations against non-redundant, Swiss-Prot, Clusters of Orthologous Groups （COG） and Kyoto Encyclopedia of Genes and Genomes （KEGG） protein databases. A subset of 58 225 transcript sequences returned hits from known proteins in the National Center for Biotechnology Information database, and the majority of the transcript sequences had the highest number of hits for Danausplexippus （50.43%）. A total of 1217 Gene Ontology-level 3 annotations were assigned to 51 805 transcripts, while 39 650 transcripts were predicted as functional protein-coding genes in the COG database and 20 037 transcripts were enriched to KEGG pathways. We identified 40 putative genes related to pheromone production and reception in S. recurvalis, with the expression of one gene between 0.29 and 1141.79 fragments per kilo base per million （FPKM） reads. The transcriptome sequence of S. recurvalis is a first step toward offering a comprehensive genomic resource which would enable better understanding of molecular mechanisms to enable development of effective pest management practices for this species.

关键词： pheromone protein-coding genes putative genes Spoladea recurvalis transcriptome

Root Morphology and Physiology in Relation to the Yield Formation of Rice

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Journal of Integrative Agriculture 2012年第6期11卷 920-926页

作者： YANG jian-chang ZHANG Hao ZHANG jian-hua Key Laboratory of Crop Genetics and Physiology of jiangsu Province/Agricultural College Yangzhou University Yangzhou 225009 PR. China School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong Kong Hong Kong P.R.China

Root system is a vital part of plant and regulates many aspects of shoot growth and development. This paper reviews how some traits of root morphology and physiology are related to the formation of grain yield in rice （Oryza sativa L.）. Higher root biomass, root oxidation activity, and cytokinin contents in roots are required for achieving more panicle number, more spikelets per panicle, greater grain-filling percentage, and higher grain yield. However, these root traits are not linearly correlated with yield components. When these traits reach very high levels, grain filling and grain yield are not necessarily enhanced. High numbers of mitochondria, Golgi bodies, and amyloplasts in root tip cells benefit root and shoot growth and yield formation. Proper crop management, such as an alternate wetting and moderate soil drying irrigation, can significantly improve ultra-structure of root tip cells, increase root length density and concentration of cytokinins in root bleedings, and consequently, increase grain-filling percentage, grain yield, and water use efficiency. Further studies are needed to investigate the mechanism underlying root-shoot and root-soil interactions for high grain yield, the roles of root-sourced hormones in regulating crop growth and development and the effects of soil moisture and nutrient management on the root architecture and physiology.

关键词： rice (Oryza sativa) root morphology and physiology grain yield grain filling alternate wetting and moderatedrying

On the Center Problem for Generalized Abel Equations

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Acta Mathematica Sinica,English Series 2023年第12期39卷 2329-2337页

作者： chang jian LIU Shao Qing WANG School of Mathematics(Zhuhai) Sun Yat-sen UniversityZhuhai 519082P.R.China

This paper is devoted to the conditions of the existence of CC-center for the generalized Abel *** some new original methods,we obtain extended results of the main theorems in the paper by Llibre and Valls(2020)and th... 详细信息

关键词： Generalized Abel equation composition condition center problem

Gas-solid flow in a high-density circulating fluidized bed riser with Geldart group B particles

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Particuology 2016年第6期14卷 103-109页

作者： jian chang KaiZhang Wenqi Zhu Yongping Yang Beijing Key Laboratory of Emission Surveillance and Control for Thermal Power Generation North China Electn'c Power University Belting 102206 China

We carried out experiments to explore and characterize the gas-solid flow dynamics of Geldart group B particles in a dense circulating fluidized bed riser. By reducing the pressure drop across the solid control valve and increasing the solid inventory in the storage tank, a high solid circulation rate and a solid holdup above 0.075 throughout the riser were simultaneously achieved. At a solid-to-gas mass flux ratio of approximately 105, flow transitioned from fast fluidization to a dense suspension upflow. In the axial direction of the riser, solid holdup had an exponential profile, increasing with increasing solid circulation rate and Jot decreasing superficial gas velocity. From the riser＇s center to its wall, the solid holdup increased markedly, exhibiting a steep parabolic profile. Increasing the solid circulation rate increased the radial non-uniformity of the solid concentration, while increasing the superficial gas velocity had the opposite effect, In our dense circulating fluidized bed riser, Geldart group B particles had similar slip characteristics to Geldart group A particles,

关键词： Circulating fluidized bed riser Dense gas-solid flow High density High flux Hydrodynamics Geldart group B particle