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Influence of Blade Number on the Performance of Hydraulic Turbines in the Transition Stage

Fluid Dynamics & Materials Processing 2024年第11期20卷 2617-2636页

作者： Fengxia Shi Guangbiao Zhao Yucai Tang dedong Ma Xiangyun Shi School of Energy and Power Engineering Lanzhou University of TechnologyLanzhou730050China Key Laboratory of Fluid Machinery and Systems of Gansu Lanzhou730050China

To analyze the effect of blade number on the performance of hydraulic turbines during the transient stage in which theflow rate is not constant,six hydraulic turbines with different blade numbers are *** instantaneous hydraulic performance of the turbine and the pressure pulsation acting on the impeller are investigated numerically by using the ANSYS CFX *** ensuing results are compared with the outcomes of experimental *** is shown that thefluctuation range of the pressure coefficient increases with time,but the corresponding range for the transient hydraulic efficiency decreases gradually when theflow velocity transits to larger *** the transition to smallflow velocity,thefluctuation range of the pressure coefficient gradually decreases as time passes,but the correspondingfluctuation range of its transient hydraulic efficiency gradually becomes *** range in the Z9 case is small during the *** main frequency of transient hydraulic efficiency pulsation is equal to the blade *** the main frequency,Z7 has the largest amplitude of the hydraulic efficiency pulsation,Z10 has the smallest amplitude,and the difference between Z7 and Z9 is *** the number of blades grows,the pressure pulsation during the transition process gradually decreases,but the pressure pulsation of Z10 at the volute tongue is *** the steady state,Z9 has the highest efficiency and in the transient stage,the pressure coefficientfluctuation range is ***,for the hydraulic turbine Z9,the performance is optimal.

关键词： Hydraulic turbine blade number transient process pressurefluctuation transient hydraulic performance

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Ce改性HZSM-5分子筛催化降解甲硫醇（CH3SH）的研究

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昆明理工大学学报（自然科学版） 2017年第2期42卷 89-94页

作者：郝湖生何德东陈定凯陆继长刘峰陈然钟丽萍韩彩芸高晓亚罗永明昆明理工大学环境科学与工程学院

采用浸渍法制备了一系列不同含量Ce改性的HZSM-5分子筛催化剂,考察它们在催化分解甲硫醇反应中的催化活性.通过XRD、BET、H2-TPR、NH3-TPD和CO2-TPD等手段对其物化性能进行表征,并讨论反应温度对不同Ce含量的HZSM-5分子筛催化活性的影响... 详细信息

采用浸渍法制备了一系列不同含量Ce改性的HZSM-5分子筛催化剂,考察它们在催化分解甲硫醇反应中的催化活性.通过XRD、BET、H2-TPR、NH3-TPD和CO2-TPD等手段对其物化性能进行表征,并讨论反应温度对不同Ce含量的HZSM-5分子筛催化活性的影响.结果表明：当Ce的含量为1%时,CeO2高度分散在HZSM-5分子筛上;当Ce含量增加时,生成结晶态的CeO2,且随Ce含量的增加,结晶态的CeO2越多,所以含量较高的Ce改性HZSM-5分子筛存在明显的还原性能,能够促进甲硫醇的催化分解;稀土Ce的引入还能够调控HZSM-5分子筛的酸碱性,而表面酸碱量的变化同时也影响了HZSM-5分子筛催化分解甲硫醇的活性.

关键词： Ce改性 HZSM-5分子筛甲硫醇还原性酸碱性

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A Rice NBS-ARC Gene Conferring Quantitative Resistance to Bacterial Blight Is Regulated by a Pathogen Effector-Inducible miRNA

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Molecular Plant 2020年第12期13卷 1752-1767页

作者： Guanghuai Jiang Dongfeng Liu dedong Yin Zhuangzhi Zhou Yue Shi Chunrong Li Lihuana Zhu and Wenxue Zhai Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China Key Laboratory of Plant Molecular Physiology Institute of BotanyChinese Academy of SciencesBeijing 100093China

The bacterium Xanthomonas oryzae ***(Xoo)causes blight in rice worldwide,resulting in signifi-cant crop ***,no gene underlying a quantitative trait locus(QTL)for resistance against Xoo has been cloned ***,we report the map-based cloning of a QTL,in which the NBS8R gene confers quantitative resistance to ***8R encodes an NB-ARC protein,which is involved in pathogen/microbe-associated molecular pattern-triggered immunity and whose expression is regulated by non-TAL effector XopQ-inducible Osa-miR1876 through DNA *** analysis of NBS8R in wild rice species and rice cultivars suggests that the Osa-miR1876 binding sites in the 5'UTR of NBS8R are inserted by chance and have undergone variations with Osa-miR1876 throughout *** inter-action between NBS8R and XopQ-inducible Osa-miR1876 is partially in keeping with the zigzag model,revealing that quantitative genes may also follow this model to control the innate immune response or basal disease resistance,and may prove valuable in utilizing the existing landraces that harbor the NBS8R gene but with no Osa-miR1876 binding site in rice breeding for bacterial blight resistance.

关键词： quantitative trait locus disease resistance bacterial blight NB-ARC microRNA DNA methylation

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Petrogenesis and Economic Potential of the Sangong MaficUltramafic Intrusion in the Eastern Tianshan, Central Asian Orogenic Belt: Constraints from Mineral, Whole-Rock, and PGE Geochemistry

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Journal of Earth Science 2024年第3期35卷 850-865页

作者： Guochao Zhou Yuwang Wang Jingbin Wang Yu Shi Hongjing Xie dedong Li Yong Fu Pan Wu College of Resources and Environmental Engineering Guizhou UniversityGuiyang 550012China Technic Research Center for Deep Resources Exploration in Non-ferrous Metal Mines Beijing Institute of Geology for Mineral Resources Co.Ltd.Beijing 100012China Sino-Zijin Resources Ltd. Beijing 100012China State Key Laboratory of Nuclear and Environment East China University of TechnologyNanchang 330013China

The Sangong Cu-Ni sulfide mineralized mafic-ultramafic intrusion is located on the southern margin of the Bogeda-Harlik belt,eastern Tianshan,*** intrusion is a well-differentiated complex and is comprised of leucogabbro,gabbro,olivine gabbro,Pl-bearing peridotite,and Pl-bearing *** Pl-bearing pyroxenite hosts both irregularly disseminated sulfide and round droplet *** intrusive rocks have a wide range of SiO_(2)(42.1 wt.%-50.48 wt.%)and MgO(6.21 wt.%-22.11 wt.%),and are enriched in light rare earth elements(LREE),large-ion lithophile elements(LILE;e.g.,Rb,Ba,Sr,and Pb),and palladium platinum group elements(PPGE)but depleted in high-field-strength elements(HFSE;e.g.,Nb,Ta,and Ti)and iridium PGEs(IPGE).These geochemical characteristics indicate that the Sangong mafic-ultramafic intrusion was derived from high degree of partial melting of depleted mantle and interacted with subduction-related *** low Pd/Ir(3.21-27.44)but high Ni/Cu(1.64-24.16)ratios,combined with the olivine crystals with low Fo(60.88-78.65)and Ni(54.99 ppm-1688.87 ppm)concentrations suggest that the parental magma of the Sangong intrusion were likely high MgO basaltic in composition that experienced extensive evolution prior *** Ce/Pb ratios(5.8-13.6)and Nb/U ratios(11.6-30.3)of the intrusive rocks all range between MORB and crustal values,the Nb/Yb and Th/Yb values are close to the lower crust values,together with the low Se/S ratios[(17-100)×10^(-6))]suggest that the magma experienced assimilation not only in mantle source but also in conduit,but the degree of crustal contamination is *** Cu/Pd ratios of the rocks range from 3.9×10^(4) to 10.8×10^(4),and the Cu/Zr ratios of Pl-bearing pyroxenite in the Sangong intrusion are>1,combined with the presence of sulfide droplets in the Pl-bearing pyroxenite,indicating the parental magma experienced sulfide saturation and the economical ore bodies may present in the depth of the ***,gi

关键词： Sangong mafic-ultramafic intrusion deposits geochemistry PGE economic potential eastern Tianshan.

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Energetic electrons associated with magnetic reconnection in the sheath of interplanetary coronal mass ejection

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Chinese Science Bulletin 2012年第12期57卷 1455-1460页

作者： HUANG ShiYong DENG XiaoHua ZHOU Meng YUAN ZhiGang LI HuiMin WANG dedong School of Electronic Information Wuhan University Wuhan 430072 China State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China Institute of Space Science and Technology Nanchang University Nanchang 330031 China

Magnetic reconnection is an important universal plasma dissipation process that converts magnetic energy into plasma thermal and kinetic energy,and simultaneously changes the magnetic field *** this paper,we report the first observation of energetic electrons associated with asymmetric reconnection in the sheath of an interplanetary coronal mass *** magnetic field shear angle was about 151°,implying guide-field *** width of the exhaust was about 8×104 *** reconnection rate was estimated as 0.044-0.08,which is consistent with fast reconnection theory and previous *** observed flux enhancements of energetic electrons with energy up to 400 keV in this reconnection *** region where ener- getic electron fluxes were enhanced is located at one pair of separatrices in the higher density *** discuss these observation results,and compare with previous observations and recent kinetic simulations.

关键词：日冕物质抛射高能电子磁重联行星际动力学模拟等离子体动能转换耗散过程

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Minimum critical thickness of dike for ore-bearing fluid injection:A new approach applied to the Shihu gold deposit,hebei Province,North China

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Geoscience Frontiers 2012年第5期3卷 717-728页

作者： dedong Li Yuwang Wang Jingbin Wang Zhaohua Luo Jiulong Zhou Zongfeng Yang Cui Liu Beijing Institute of Geology for Mineral Resources Beijing 100012 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

According to the metallogenic theory by transmagmatic fluid （TMF）, one magmatic intrusion is a channel of ore-bearing fluids, but not their source. Therefore, it is possible to use TMF＇s ability for injection into and for escaping t^om the magmatic intrusion to evaluate its ore-forming potential. As the ore-bearing fluids cannot effectively inject into the magmatic intrusion when the magma fully crystal- lized, the cooling time and rates viscosity varied can be used to estimate the minimum critical thickness of the intrusion. One dimensional heat transfer model is used to determine the cooling time for three representative dikes of different composition （granite porphyry, quartz diorite and diabase） in the Shihu gold deposit. It also estimated the rates viscosity varied in these time interval. We took the thickness of dike at the intersection of the cooling time -- thickness curve and the rates viscosity varied versus thick- ness curve as the minimum critical thickness. For the ore-bearing fluids effectively injecting into the magma, the minimum critical thicknesses for the three representative dikes are 33.45 m for granite porphyry, 8.22 m for quartz diorite and 1.02 m for diabase, indicating that ore-bearing dikes must be thicker than each value. These results are consistent with the occurrence of ore bodies, and thus they could be applied in practice. Based on the statistical relationship between the length and the width of dikes, these critical thicknesses are used to compute critical areas： 0.0003--0.0016 km2 for diabase, 0.014--0.068 km2 for quartz diorite and 0.011-0.034 km2 for granite porphyry. This implies that ore- bearing minor intrusions have varied areas corresponding to their composition. The numerical simulation has provided the theoretical threshold of exposed thickness and area of the ore-bearing intrusion. These values can be used to determine the ore-forming potentials of dikes.

关键词： Dike swarm Cooling time Numerical simulationMinor intrusion Critical thickness Transmagmatic fluid

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VO2·0.2H2O nanocuboids anchored onto graphene sheets as the cathode material for ultrahigh capacity aqueous zinc ion batteries

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Nano Research 2020年第1期13卷 215-224页

作者： dedong Jia Kun Zheng Ming Song Hua Tan Aitang Zhang Lihua Wang Lijun Yue Da Li Chenwei Li Jingquan Liu College of Material Science and Engineering Institute for Graphene Applied Technology InnovationSchool of Electromechanical EngineeringQingdao UniversityQingdao266071China College of Chemistry and Chemical Engineering Xuzhou University of TechnologyXuzhou221111China School of Physical and Mathematical Sciences Nanyang Technological UniversitySingapore637371Singapore

Aqueous Zinc-ion batteries(ZIBs),using zinc negative electrode and aqueous electrolyte,have attracted great attention in energy storage field due to the reliable safety and low-cost.A composite material comprised of VO2·0.2H2O nanocuboids anchored on graphene sheets(VOG)is synthesized through a facile and efficient microwave-assisted solvothermal strategy and is used as aqueous ZIBs cathode *** to the synergistic effects between the high conductivity of graphene sheets and the desirable structural features of VO2·0.2H2O nanocuboids,the VOG electrode has excellent electronic and ionic transport ability,resulting in superior Zn ions storage *** Zn/VOG system delivers ultrahigh specific capacity of 423 mAh·g^−1 at 0.25 A·g^−1 and exhibits good cycling stability of up to 1,000 cycles at 8 A·g^−1 with 87%capacity *** structural and elemental characterizations confirm that the interlayer space of VO2·0.2H2O nanocuboids can adapt to the reversible Zn ions insertion/*** as-prepared VOG composite is a promising cathode material with remarkable electrochemical performance for low-cost and safe aqueous rechargeable ZIBs.

关键词： VO2·0.2H2O nanocuboids graphene sheet aqueous zinc-ion battery ultrahigh capacity electron and ion transport

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Effects of Bioorganic Fertilizers on the Leaf Antioxidant Enzyme Activity and the Photosynthetic Characteristics of Replanted Szechuan Pepper, Zanthoxylum simulans

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Journal of Agricultural Science and Technology(B) 2020年第4期10卷 255-263页

作者： Shuheng Zhang Jing he Bin Wang Xiaoyan Zhang Qi Liu dedong Ding College of Forestry Gansu Agricultural UniversityLanzhou 730070People’s Republic of China College of Forestry Northwest A&F UniversityYangling 712100People’s Republic of China Institute of Ecological Forestry Sichuan Agricultural UniversityChengdu 611130People’s Republic of China

Continuous cropping obstacles hamper the efficient growth and yield of Szechuan pepper,Zanthoxylum *** current study investigated the impact of different levels of bioorganic fertilizer on the leaf physiological and photosynthetic characteristics of *** to provide a theoretical reference for continuous *** crop cultivation.A bioorganic fertilizer was used to treat seedlings growing in 25-year-old continuous cropping *** fertilizer treatments were *** impacts of the treatments on the activity of defense enzyme and photosynthetic parameters of *** leaves were *** different concentrations of bioorganic fertilizer reduced to varying degrees the malondialdehyde(MDA)content and intercellular CO2 concentration(Ci),and increased the activity of peroxidase(POD),superoxide dismutase(SOD),and ascorbate peroxidase(APX),as well as the chlorophyll content,net photosynthetic rate(Pn),stomatal conductance(Gs)and transpiration rate(Tr)of *** *** results showed that most significant increases or decreases were achieved with 100 g/L bioorganic fertilizer(Y2).Thus,the application of bioorganic fertilizer at a rate of 100 g/L can significantly improve the activity of relevant defense enzymes and photosynthetic parameters of ***,and reduce the MDA content,enhancing the stress resistance of the plants,promoting their growth and addressing,to some extent,obstacles associated with continuous cultivation.

关键词： Bio-organic fertilizer continuous cropping obstacle Zanthoxylum simulans antioxidant enzyme activity photosynthetic characteristics

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Petrogenesis and Metallogenesis of the Niumaoquan Gabbroic Intrusion Associated with Fe-Ti Oxide Ores in the Eastern Tianshan, NW China

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Acta Geologica Sinica(English Edition) 2018年第5期92卷 1862-1878页

作者： SHI Yu WANG Yuwang WANG Jingbin XIE Hongjing MAO Qigui ZHAO Lutong LONG Lingli LI dedong ZHOU Guochao Beijing Institute of Geology for Mineral Resources Beijing 100012 China School of Earth Sciences and Resources China University of Geosciences Beijing 100083 China

The Niumaoquan layered gabbroic intrusion is in the southern margin of the Central Asian Orogenic Belt in North Xinjiang, China, and hosts a Fe-Ti oxide deposit in its evolved gabbroic phases. In this paper, we report zircon U-Pb age, Sr-Nd-Hf isotopes, plagioclase chemistry, and whole-rock geochemistry of the Niumaoquan layered gabbroic intrusion. Zircon grains separated from an anorthosite sample analyzed by laser ablation inductively coupled plasma mass spectrometry yielded a concordia age of 314.7±0.74 Ma, indicating that the Niumaoquan ore-bearing gabbroic intrusion was emplaced during the Late Carboniferous. The olivine gabbro texture and plagioclase chemistry suggest that plagioclase was an early crystallized silicate phase that crystallized prior to olivine. Fractional crystallization and accumulation of plagioclase significantly controlled the evolution of the Niumaoquan gabbroic intrusion and contributed to the formation of anorthosite layers, causing metallogenic elements to become enriched in the residual melt. The Niumaoquan gabbroic intrusion is characterized by the enrichment of large ion lithophile elements and depletion of high field strength elements, positive zircon εHf（t） values（＋2.1 to ＋12.2）, positive εNd（t） values（＋3.3 to ＋5.2）, and low initial ^（87）Sr/^（86）Sr ratios（0.7039 to 0.7047）, suggesting that the parental magma was produced by interactions between metasomatized lithospheric mantle and depleted asthenospheric melts at an early post-collision stage. The Fe-Ti oxide mineralization of the Niumaoquan intrusion benefited from interactions between depleted asthenospheric melts and lithospheric mantle, and fractional crystallization of abundant plagioclase and magnesian minerals.

关键词： anorthosite chronology Fe-Ti oxide Niumaoquan Eastern Tianshan

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Artificial Intelligence Identification of Multiple Microfossils from the Cambrian Kuanchuanpu Formation in Southern Shaanxi, China

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 189-197页

作者： ZHANG Tao WANG Bin LI dedong NIU Ben SUN Jie SUN Yifei YANG Xiaoguang LUO Juan HAN Jian School of Information Science&Technology Northwest University.Chang’an DistrictXi’an 710075China Shaanxi Key Laboratory of Early Life and Environmensts State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest UniversityXi’an 710069China

The Cambrian Kuanchuanpu Formation in southern Shaanxi, China is a critical window for the understanding of the Cambrian explosion, because of abundant and various exceptionally preserved metazoans and embryo fossils yielded. The efficiency of traditional sample manually selecting with microscopes is quite low and hinder the discoveries of new species, thus recognition and classification of microfossils by artificial intelligence(AI) is substantially in the request. In this paper, we develop a procedure for fossil area segmentation in common multi-typed mixed photos by improved watershed algorithm. And for better fossil recognition, previous histogram of oriented grandient(HOG) algorithm is replaced by scale invariant feature transform(SIFT), which is feasible for the segmented images and increase the accuracy significantly. Thus, the scope of application of AI fossil recognition can be extended form single fossil image to multi-typed mixed images and the reliability is also secured, as the result of our test presents a high(at least 84%) accuracy of fossil recognition.

关键词： watershed segmentation scale invariant feature transform visual vocabulary support vector machine

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