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Numerical investigation of alleviation of undesirable effect of inter-blade vortex with air admission for a low-head Francis turbine

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Journal of Hydrodynamics 2020年第6期32卷 1151-1164页

作者： Long-gang Sun Peng-cheng Guo luo-chang Wu State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an710048China

In order to compensate for the stochastic nature of the power grid due to the tremendous development and the integration of renewable energy resources and meet its other requirements,the hydraulic turbines are forced to operate more frequently under partial load conditions with singular and misaligned flows inevitably excited by the inter-blade *** paper presents numerical investigations of the unsteady characteristics of the inter-blade vortex for a low-head model Francis *** SST k-ωturbulent model is used to close the unsteady Reynolds-averaged Navier-Stokes(RANS)*** flow structure of the inter blade vortex predicted by the numerical simulation is confirmed by experimental *** is shown that the total vortex volume in the runner sees a quasi-periodical oscillation,with significant flow separations created on the suction side of the runner blade.A counter measure by using the air admission into the water from the head cover is implemented to alleviate the undesirable effect of the inter-blade *** analyses show that the development of the inter-blade vortex is significantly mitigated by the injecting air that controls and changes the spatial distribution of ***,the flow aeration with a suitable air flow rate can reduce the energy dissipation caused by the inter-blade vortex and plays a critical role in preventing the excessive amplitudes of the pressure fluctuation on the suction side of the runner *** investigation provides an insight into the flow mechanism underlying the inter-blade vortex and offers a reference to alleviate and mitigate the adverse consequences of the inter-blade vortex for the Francis turbine.

关键词： Numerical simulation inter-blade vortex air admission energy dissipation pressure fluctuation Francis turbine

X-ray Photoemission Spectroscopy Studies of the Semiconducting Molybdenum Purple Bronze Bi_(0.2)MoO_3

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Journal of Materials Science & Technology 2006年第4期22卷 487-490页

作者： Rui XIONG chang luo Wufeng TANG Jing SHI Department of Physics Wuhan University Wuhan 430072 China International Center for Materials Physics Chinese Academy of Sciences Shenyang 110016 China

The electronic structure of the quasi-two-dimensional （2D） semiconducting molybdenum purple bronze Bio.2MoO3 was presented by X-ray photoemission spectroscopy. The valence band of Bio.2MoO3 is made up of Opπ nonbonding level, π and a bonding bands. The peak at 1.5 eV and the shoulder at 0.5 eV in the forbidden band may be formed from the non-bonding dxy orbitals of some Mo atoms. The O1s core-level spectrum demonstrates the presence of two inequivalent bonds of oxygen ions in Bio.2MoO3. Bi4f core-level spectrum shows two bonding characters of Bi atoms in bismuth molybdenum single crystal. Mo3d core-level spectrum confirms two kinds of valence states of Molybdenum （Mo^＋5 and Mo^＋6）. Ar^＋ ion irradiation induces more significant distortion of MoO6 octahedra.

关键词： Bi0.2MoO3 single crystal X-ray photoemission spectroscopy Core-electron spectrum

Retinoblastoma: concerning its initiation and treatment

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International Journal of Ophthalmology(English edition) 2013年第3期6卷 397-401页

作者： chang luo Ying-Ping Deng Department of Ophthalmology West China Hospital Sichuan University

·Retinoblastoma (RB) is the most common intraocular cancer of infancy and childhood. This cancer is initiated by mutation on , the tumor suppressor gene that is responsible for the regulation of both cell cycle and gnome stability in retinal cells. Patients with a constitutional mutation on can be inherited. RB occurs approximately 1 in every 15 000-20 000 live births. The worldwide mortality for this cancer is about 5%-11%. However, this rate rises to about 40%-70% in developing countries due to a delay in diagnosis. A wide variety of options are available for the treatment, but often a combination of therapies is adopted to optimize individualized care. ·

关键词： retinoblastoma retinoblastomal gene leukocoria epidemiology medical management

High-performance chromite by structure stabilization treatment

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Journal of Iron and Steel Research International 2020年第2期27卷 169-179页

作者： En-hui Wang chang luo Jun-hong Chen Xin-mei Hou Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Chromite is an important raw material applied in *** have been made to obtain high-performance chromite by adding MgO and Al203 from the viewpoint of structure *** order to explore the effect of Al203 and MgO on the structure,two formulas,i.e.,Mg-rich and Al-rich ones,were *** phase and microstructure development of samples heated in the temperature range of 1200-1600℃ were studied by X-ray diffraction and scanning electron microscopy with energy-dispersive *** and Al203 added have diffused into chromite successfully by heat *** diffuses into chromite,occupying the tetrahedral vacancies caused by the diffusion and oxidation of Fe2+ions to stabilize the ***203 diffuses into the surface layer of chromite,forming spinel-sesquioxide ***-rich sample which has spinel-sesquioxide structure shows better corrosion resistance toward fayalite slag than Mg-rich sample which has single spinel structure by blocking the interdiffusion between Fe^2+ions in fayalite slag and Mg^2+ions in chromite.

关键词： Chromite Structure optimization Corrosion resistance Refractory

Comparative transcriptome analysis of Ts(Resistant genotype)and Ma(Susceptible genotype)marigold(Tagetes erecta L.)leaves in response to Alternaria tagetica

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Horticultural Plant Journal 2023年第2期9卷 321-334页

作者： Xi Cheng Dongliang Chen chang luo Hua Liu Conglin Huang Institute of Grassland Flowers and EcologyBeijing Academy of Agriculture and Forestry SciencesBeijing 100097China Beijing Engineering Research Center of Functional Floriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China

Marigold black spot caused by Alternaria tagetica is a major disease that can decrease marigold production by 40%,resulting in serious economic *** this study,we identified many genes responsive to *** in the resistant and susceptible marigold *** of differentially expressed genes,expression trends,and a weighted gene co-expression network revealed a series of hub genes with key roles in different *** infection ***,1216 unigenes encoding transcription factors from eight families were differentially expressed between Ts and ***,R genes fromvarious families(e.g.,N,NL,RLP,and TNL)were differentially expressed in the twomarigold genotypes before and after the inoculation with *** diagrams were used to visualize the leaf transcriptional changes in the two marigold genotypes infected by *** to clarify the effects of *** on the expression patterns of genes involved in phosphatidylinositol signaling,plant–pathogen interactions,and plant hormone signal *** identified candidate genes related to disease resistance and generated valuable resources for analyzing the candidate gene functions related to black spot resistance in *** study data may be useful for the molecular marker-assisted screening and breeding of marigold lines with increased disease resistance.

关键词： Tagetes erecta Co-expression network Gene expression Black spot resistance Transcriptional modules

On Two-machine Flow Shop Scheduling

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Journal of the Operations Research Society of China 2014年第3期2卷 333-339页

作者： Lin Chen Wen-chang luo Guo-Chuan Zhang College of Computer Science Zhejiang UniversityHangzhou 310027China Faculty of Science Ningbo UniversityNingbo 315211China

In this note,we revisit the classical two-machine flow shop scheduling problem.A linear time approximation scheme is *** an online version with rejection,we propose best possible online algorithms.

关键词： Flow shop Linear time Online algorithm

SSR Analysis of Genetic Relationship and Classification in Chrysanthemum Germplasm Collection

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Horticultural Plant Journal 2018年第2期4卷 73-82页

作者： luo chang CHEN Dongliang CHENG Xi LIU Hua LI Yahui HUANG Conglin Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Sciences Beijing Engineering Research Center of Functional Floriculture Beijing Key Laboratory of Agricultural Genetic Resources and Biotechnology

To further test the accuracy and rationality of the Chinese classification system for chrysanthemum(Chrysanthemum morifolium), 10 simple sequence repeat(SSR) markers were used to identify a collection of 88 chrysanthemum and its related genera accessions. In total, 42 effective alleles across 88 accessions were detected; 3 429 bands were obtained by PCR amplification, including 2 630 polymorphic bands. The similarity coefficient ranged from 0.53 to 0.88. Cluster analysis based on UPGMA illustrated that the wild species and large-flower cultivars were first divided into two clusters, then the large-flower cultivars formed five distinct groups according to petal type, indicated that petal type can be a classification criterion. In the wild species cluster, C. vestitum and C. zawadaskii grouped with A. trilobata, suggested that the Ajania genera was closely related to the Chrysanthemum genera. ‘Hangbaiju’, ‘Gongju’ and ‘Chuju’ were grouped together, and ‘Boju’, O. longilobus and C. mongolicum constituted another branch, showed a correlation with geographic region of origin. Population structure analysis was subsequently performed with K values ranging from 2 to 10, and the most likely estimate for the population structure is five subpopulations, which is nearly consistent with the clustering results. Principle component analysis was further performed to verify the classification results. The results showed that these SSR markers are very powerful for studying genetic relationships and will be useful tools in the identification and classification of chrysanthemum.

关键词： chrysanthemum SSR polymorphism genetic relationship classification

Domain Decomposition Method Modified by Characteristic Finite Element Procedure for System of Parabolic Equations with Discontinuous Coefficients

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Numerical Mathematics A Journal of Chinese Universities(English Series) 2006年第4期15卷 336-347页

作者： luo chang Department of Mathematics Shandong University Weihai 264209 China

In this work, system of parabolic equations with discontinuous coefficients is studied. The domain decomposition method modified by a characteristic finite element procedure is applied. A function is defined to approximate the fluxes on inner boundaries by using the solution at the previous level. Thus the parallelism is achieved. Convergence analysis and error estimate are also presented.

关键词：间断系数比喻方程系统域分解特征有限元

Floral display and breeding system of Jatropha curcas L.

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Forestry Studies in China 2007年第2期9卷 114-119页

作者： luo chang-wei Li Kun Chen You Sun Yong-yu Research Institute of Insect Resources Chinese Academy of Forestry Kunming 650224 P. R. China Yunnan Provincial Forestry Vocational College Kunming 650224 P. R. China

Plant flowering and breeding characteristics are important for us to understand the reproduction of plant populations. In this paper, we studied the reproduction characteristics of Jatropha curcas in Yuanjiang County （23°36＇1＇4, 101°00＇E）, Yunnan Province. The plant produces flowers in dichasial inflorescences. Normally, the flowers are unisexual, and male and female flowers are produced in the same inflorescence. Only a few male flowers are produced in an inflorescence, and fruits are produced only through pollination between different flowers from the same or different plants. By the treatments of emasculation, bagging and artificial pollination in this experiment, there were few but same fruit set ratios when the inflorescences were emasculated, bagged, or bagged with net, except artificial pollination treatments, which showed that Jatropha curcas could produce fruit through apomixis but not wind pollination. When the inflorescences were unbagged, unemasculated and with free pollination treatments, or bagged, emasculated and with artificial cross-pollination treatments, or unbagged, emasculated and with free pollination treatments, there were many fruits produced. It showed that Jatropha curcas shows outcrossing, is self-compatible, and demanding for pollinators. Normally, the male flowers open first and a few flowers bloom in one day in a raceme. These flowers last a long time in bloom. However, a large number of female flowers open from the third to the fifth day, with some female flowers opening first in a few raceme. This shows a tendency to promote xenogamy and minimize geitonogamy.

关键词： Jatropha curcas floral display breeding system outcrossing index pollen-ovule ratio