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Survey on performance of vertical slot and nature-like fishways at Angu hydropower station, Southwest China

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Water Science and Engineering 2024年第1期17卷 83-91页

作者： Jun-jian Sun Jia-yue Shi Qi Zhang Xiao-tao Shi Jun-jun Tan PowerChina Huadong Engineering Corporation Limited Hangzhou 311122China Hubei International Science and Technology Cooperation Base of Fish Passage China Three Gorges UniversityYichang 443002China

To restore dam-blocked natural fish migratory passages,a growing number of artificial fishways have been built in water conservancy and hydropower projects in China.The Angu hydropower station involved diverse important fish habitats in the lower reaches of the Daduhe River in Southwest China.Therefore,a vertical slot fishway(VSF)and a nature-like fishway(NLF)were built near the backwater area of the reservoir to connect the upstream and downstream habitats.Hydrodynamic and aquatic ecological surveys were conducted after the completion of the project to estimate the fish passing effect of the two fishways.The results indicated that both fishways were in effective operation and could maintain the desired hydrodynamic conditions and be used by several local fish species.During the survey,149 fish from 15 species and 111 fish from 17 species were captured by the traps in the VSF and NLF,respectively,while 1263 fish from 27 species were found in the downstream area.Some species captured in the VSF were not found in the NLF,and vice versa,which implied the different preferences of fish.Meanwhile,3789 signals including 2099 upward ones and 1690 downward ones were monitored with an ultrasonic fish detector at the inlet of the VSF.These findings revealed the characteristics of fish species observed in and near the fishways and provided valuable insights into the different fish passing capabilities of VSFandNLF.

关键词： Vertical slot fishway Nature-like fishway Aguatic ecological survey Fishwaymonitoring Statistical analysis

Attractive natural products with strained cyclopropane and/or cyclobutane ring systems

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Science China Chemistry 2016年第9期59卷 1126-1141页

作者： Yao-yue Fan Xin-Hua Gao jian-Min yue Shanghai Institute of Materia Medica Chinese Academy of Sciences

The strained cyclopropane and/or cyclobutane subunits occurred in many complex natural products including terpenoids, steroids and alkaloids. Natural products with cyclopropane and/or cyclobutane motifs not only furnished fascinating structures, but also exhibited versatile biological activities, such as cytotoxic, anti-HIV, antimicrobial, antiviral, and immunosuppressive effects. This review covered a large array of structurally unique natural products with strained cyclopropane and/or cyclobutane motifs and summarized their structural features, distributions, biological activities, as well as biogenetic considerations.

关键词：天然产品环丙烷吸引力系统免疫抑制作用结构特征天然产物生物活性

Evaluation of lightning-induced overvoltage on a 10 kV distribution line based on electromagnetic return-stroke model using finite-difference time-domain

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High Voltage 2024年第2期9卷 356-366页

作者： Pan Duan Lianfang Zhang Xiaogang Huang jian Sun yue Qi Qing Yang School of Automation Chongqing University of Posts and TelecommunicationsChongqingChina Chongqing Power Co Tongnan BurChongqingChina China Southern Power Grid Science Research Institute GuangzhouChina State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqingChina

Accurate simulation of lightning-induced overvoltage for overhead distribution lines is helpful to prevent lightning trip accidents.An electromagnetic return-stroke model was used to represent lightning and then a 3D finite-difference time-domain(FDTD)method was adopted to simulate the lightning-induced overvoltage on a distribution line without a field-line coupling model.How lightning-induced overvoltage behave for different ground conductivity and varying distance between the distribution line and the lightning channel was analysed.The results showed that the overvoltage waveforms at the centre point of the line corresponding to lightning strikes on the lossy ground and an ideal ground(σ=∞)were similar;however,the peak amplitudes of the waveform were affected by soil conductivity at a close distance.The relationship between magnitude of the overvoltage and distance can be described by a second-order exponential decay equation.Finally,the overvoltage calculated using the proposed model was compared with those obtained based on Agrawal's model and measurements made using the newly developed intelligent insulator on site.From these comparisons,it could be concluded that the FDTD method with the electromagnetic return-stroke model produces reasonably accurate results of the attenuated oscillation waveform,which can better reproduce the overvoltage on operational distribution lines.

关键词： lightning distribution return

Sample based 3D face reconstruction from a single frontal image by adaptive locally linear embedding

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第4期8卷 550-558页

作者： ZHANG jian ZHUANG yue-ting School of Computer Science and Technology Zhejiang University Hangzhou 310027 China

In this paper, we propose a highly automatic approach for 3D photorealistic face reconstruction from a single frontal image. The key point of our work is the implementation of adaptive manifold learning approach. Beforehand, an active appearance model (AAM) is trained for automatic feature extraction and adaptive locally linear embedding (ALLE) algorithm is utilized to reduce the dimensionality of the 3D database. Then, given an input frontal face image, the corresponding weights between 3D samples and the image are synthesized adaptively according to the AAM selected facial features. Finally, geometry reconstruction is achieved by linear weighted combination of adaptively selected samples. Radial basis function (RBF) is adopted to map facial texture from the frontal image to the reconstructed face geometry. The texture of invisible regions between the face and the ears is interpolated by sampling from the frontal image. This approach has several advantages: (1) Only a single frontal face image is needed for highly automatic face reconstruction; (2) Compared with former works, our reconstruction approach provides higher accuracy; (3) Constraint based RBF texture mapping provides natural appearance for reconstructed face.

关键词：三维人脸重建单张正面像自适应局部线性嵌入 RBF插值

Evolution of MnO–SiO2–Al_(2)O_(3)–MgO inclusions during heat treatment at 1100℃

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Journal of Iron and Steel Research(International) 2024年第5期31卷 1221-1231页

作者： Xu-bo Lei jian-li Li Qiang Zeng Hang-yu Zhu yue Yu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina

To investigate the evolutionary behavior of the MnO–SiO_(2)–Al_(2)O_(3)–MgO inclusions during heat treatment,water quenched samples were isothermally held at 1100°C for 120 min in Ar and air atmosphere,and the obtaining samples were analyzed by X-ray diffraction,scanning electron microscopy and energy dispersive spectrometer.It showed that 3MnO·Al_(2)O_(3)·3SiO_(2)and MnO·SiO_(2)were detected in the 5 wt.%MgO system after isothermal holding in Ar atmosphere,while MgO·Al_(2)O_(3),MnO·SiO_(2)and Mn7O8·SiO4 were detected in air atmosphere.The evolutionary behavior of the 10,15 and 20 wt.%MgO systems after isothermal holding in different atmosphere were consistent.Oxygen affected the solid phase transformation of the low MgO content systems.The calculation results of FactSage 8.1 showed that MgO·Al_(2)O_(3)was formed in the 5 wt.%MgO system with air atmosphere.The solid phase transformation was accompanied by grain coarsening during the isothermal holding process.The differences in the solid phase transformation in different atmosphere of the 5 wt.%MgO system indicated that it was a gas-phase transport grain coarsening mechanism.The enrichment of Al element in the liquid phase region at the grain edges,the homogeneous distribution of Mg element and the disappearance of the liquid phase within the crystal revealed that other MgO content systems were liquid–solid transport grain coarsening mechanism.

关键词： Evolution Glassy phase Inclusion Heat treatment MgO·Al_(2)O_(3)

Connection Between Continuous Optimization and Turán Densities of Non-uniform Hypergraphs

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Acta Mathematicae Applicatae Sinica 2021年第4期37卷 858-866页

作者： Xiao-bing GUO yue-jian PENG School of Mathematics Hunan UniversityChangsha410082China

A classical result of Motzkin and Straus established the connection between the Lagrangian of a graph and its maximum cliques.Applying it,they gave a new proof of Turán’s theorem.This aroused the interests in studying the connection between continuous optimization and extremal problems in combinatorics.In 2009,S.Rota Bulòand M.Pelillo extended the result of Motzkin-Straus to r-uniform hypergraphs.Recently,Johnston and Lu initiated the study of the Turán density of a non-uniform hypergraph.Polynomial optimization problems related to several types of non-uniform hypergraphs and its applications on Turán densities have also been studied.In this paper,we obtain a Motzkin-Straus type of results for all non-uniform hypergraphs.Applying it,we give an upper bound of the Turán density of a complete non-uniform hypergraph.

关键词： hypergrapli maximum clique polynomial optimization

The brassinosteroid signaling component SlBZR1 promotes tomato fruit ripening and carotenoid accumulation

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Journal of Integrative Plant Biology 2023年第7期65卷 1794-1813页

作者： Fanliang Meng Haoran Liu Songshen Hu Chengguo Jia Min Zhang Songwen Li Yuanyuan Li Jiayao Lin yue jian Mengyu Wang Zhiyong Shao Yuanyu Mao Lihong Liu Qiaomei Wang Key Laboratory of Horticultural Plant Growth and Development Ministry of AgricultureDepartment of HorticultureZhejiang UniversityHangzhou 310058China College of Plant Science Jilin UniversityChangchun 130062China

The plant hormone ethylene is essential for climacteric fruit ripening, although it is unclear how other phytohormones and their interactions with ethylene might affect fruit ripening. Here, we explored how brassinosteroids(BRs) regulate fruit ripening in tomato(Solanum lycopersicum) and how they interact with ethylene. Exogenous BR treatment and increased endogenous BR contents in tomato plants overexpressing the BR biosynthetic gene SlCYP90B3promoted ethylene production and fruit ripening.Genetic analysis indicated that the BR signaling regulators Brassinazole-resistant1(SlBZR1) and BRI1-EMS-suppressor1(SlBES1) act redundantly in fruit softening. Knocking out Sl BZR1 inhibited ripening through transcriptome reprogramming at the onset of ripening. Combined transcriptome deep sequencing and chromatin immunoprecipitation followed by sequencing identified 73 Sl BZR1-repressed targets and 203 Sl BZR1-induced targets involving major ripening-related genes, suggesting that Sl BZR1 positively regulates tomato fruit ripening.Sl BZR1 directly targeted several ethylene and carotenoid biosynthetic genes to contribute to the ethylene burst and carotenoid accumulation to ensure normal ripening and quality formation. Furthermore,knock-out of Brassinosteroid-insensitive2(Sl BIN2),a negative regulator of BR signaling upstream of Sl BZR1, promoted fruit ripening and carotenoid accumulation. Taken together, our results highlight the role of Sl BZR1 as a master regulator of tomato fruit ripening with potential for tomato quality improvement and carotenoid biofortification.

关键词： brassinosteroids carotenoids ethylene fruit ripening quality improvement SlBIN2 SlBZR1 tomato

Chemical constituents from Vernonia bockiana

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Chinese Journal of Natural Medicines 2019年第12期17卷 924-927页

作者： DONG Shi-Hui WU Yan yue jian-Min State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000China

A new sesquiterpenoid and two pregnane steroids,named vernobockolide C(1)and vernobockones A and B(2 and 3),respevtively,along with a known sesquiterpenoid,7,10-epoxy-11-hydroxy-bisabol-2-en-15-al,were isolated from the aerial part of Vernonia bockiana.Their structures were elucidated on the basis of extensive spectroscopic data analysis,especially 2 D NMR(HSQC,HMBC,and ROESY).This study further expands the chemical space of this underexplored species.

关键词： Vernonia bockiana Sesquiterpenoid Steroid

Manipulation of internal blockage in triangular triple quantum dot

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Chinese Physics B 2024年第5期33卷 588-593页

作者：齐月魏建华 Department of Physics Renmin UniversityBeijing 100876China

We utilize the calculation of hierarchical equations of motion to demonstrate that the spin-dependent properties between adjacent quantum dots(QDs)can be changed by breaking the internal symmetry configuration,corresponding to the inversion of dominant chiral states.In the linear triple quantum dots(LTQDs)connected to two electron reservoirs,we can observe that the blockage appears at the triangle triple quantum dots(TTQDs)by gradually increasing the coupling strength between next-nearest double QDs.When the initial coupling between LTQDs has altered,the internal chiral circulation also undergoes the corresponding transform,thus achieving qualitative regulation and detection of the blocking region.We also investigate the response of the chiral circulation to the dot–lead coupling strength,indicating the overall robust chiral circulation of the TTQDs frustration.

关键词： quantum dots chiral topology blocking