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Numerical Simulation of Failure during Cylindrical Cup Hydrodynamic Deep Drawing

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Journal of Materials Science & Technology 2001年第1期17卷 133-134页

作者： Lihui lang Dachang KANG Zhongren WANG Shijian YUAN School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China

In this paper, a method to combine the mathematical analytic equation and general FEM software has been applied in the simulation of hydrodynamic deep drawing (HDD) cylindrical cup, also the failure types such as frac... 详细信息

关键词： deep drawing

Promoting effect of super absorbent polymer on hydrate formation

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Journal of Natural Gas Chemistry 2010年第3期19卷 251-254页

作者： Fei Long Shuanshi Fan Yanhong Wang Xuemei lang The Key Laboratory of Enhanced Heat Transfer and Energy Conservation Ministry of Education School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 Guangdong China

The effect of super absorbent polymer（SAP） on the formation of tetrahydrofuran（THF） hydrate was studied by the successional cooling *** was found that THF solution samples with 0.004 wt% and 0.03 wt% of SAP formed THF hydrate completely during the same cooling *** corresponding induction time was 16-29 min,14-31 min,respectively,which was obviously shorter than that of THF solution samples without SAP（25-62 min）.It indicated that SAP accelerated the formation of THF *** the same time,the pictures of hydrate formation with and without SAP had been *** was found that SAP did not change the morphology of the ***,the mechanism of SAP promoting effect on the formation of THF hydrate was suggested.

关键词： super absorbent polymer tetrahydrofuran hydrate promoting effect

Two new species from Sulawesi and Borneo facilitate phylogeny and taxonomic revision of Engelhardia(Juglandaceae)

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Plant Diversity 2022年第6期44卷 552-564页

作者： Hong-Hu Meng Can-Yu Zhang Shook ling Low lang Li Jian-Yong Shen Nurainas Yu Zhang Pei-Han Huang Shi-Shun Zhou Yun-Hong Tan Jie Li Plant Phylogenetics and Conservation Group Center for Integrative ConservationXishuangbanna Tropical Botanical GardenChinese Academy of SciencesKunming 650223YunnanChina Yunnan Normal University Kunming 650500YunnanChina Bonn University Botanic Gardens Meckenheimer Allee 171D-53115 BonnGermany The Center for Gardening and Horticulture Xishuangbanna Tropical Botanical GardenChinese Academy of Sciences Mengla 666303YunnanChina Department of Biology Faculty of Math.&Nat.Sci.Andalas UniversityPadang 25163West SumatraIndonesia Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesNay Pyi Taw 05282Myanmar Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMengla 666303YunnanChina University of Chinese Academy of Science 100049BeijingChina

Engelhardia,a genus of Juglandaceae(the walnut family),is endemic to tropical and subtropical *** rich Cenozoic fossil records and distinctive morphological characters of the living plants have been used to explore the evolutionary history and geographic distribution of ***,the taxonomy of this genus has been suffered from a lack of in-depth investigation and good specimens across its distribution *** delimitation of Engelhardia was defined with seven species in 2020,but detailed information on the circumscription of the species still remains poorly *** this study,two new species are described from Sulawesi and Borneo,Engelhardia anminiana and *** also revised and reconstructed the phylogeny within Engelhardia using morphological,molecular(plastid and ribosomal),and distribution *** sampled 787 individuals in 80 populations,and all the samples were genotyped using plastid regions,trnS-trnG,rps16,trnL-trnF,psbA-trnH,and rpl32-trnL;one ribosomal region,nuclear ribosomal internal transcribed spacer(nrITS).The all datasets were used to reconstruct the phylogenetic ***,the molecular analyses were combined for 738 sheets of specimens with 15 morphological characteristics to further explore the morphological clusters of *** analysis using morphological data confirmed the delimitation of nine Engelhardia ***,phylogenetic analysis based on molecular data(i.e.,plastid and ribosomal)supported the monophyly of Engelhardia and generated phylogenetic trees that included ***,***,***,***,***,***,***,*** and the varieties of ***(i.e.,*** ***,*** ***,*** ***,and *** ***).Our comprehensive taxonomic revision of Engelhardia will provide an insight into understanding the plant diversity in tropical and subtropical Asia.

关键词： Engelhardia Taxonomic notes Morphological clustering Phylogeny Distribution

Gravitational and electromagnetic radiation from binary black holes with electric and magnetic charges:hyperbolic orbits on a cone

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Communications in Theoretical Physics 2023年第6期75卷 103-111页

作者： Zu-Cheng Chen Sang Pyo Kim lang Liu Department of Astronomy Beijing Normal UniversityBeijing 100875China Advanced Institute of Natural Sciences Beijing Normal UniversityZhuhai 519087China Department of Physics and Synergistic Innovation Center for Quantum Effects and Applications Hunan Normal UniversityChangshaHunan 410081China Department of Physics Kunsan National UniversityKunsan 54150Korea

We derive the hyperbolic orbit of binary black holes with electric and magnetic *** the low-velocity and weak-field regime,by using the Newtonian method,we calculate the total emission rate of energy due to gravitational and electromagnetic radiation from binary black holes with electric and magnetic charges in hyperbolic ***,we develop a formalism to derive the merger rate of binary black holes with electric and magnetic charges from the twobody dynamical *** apply the formalism to investigate the effects of the charges on the merger rate for the near-extremal case and find that the effects cannot be ignored.

关键词： gravitational waves magnetic charges black holes

Strengthening granulation behavior of specularite concentrates based on matching of characteristics of iron ores in sintering process

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Journal of Iron and Steel Research International 2018年第10期25卷 1017-1025页

作者： Sheng-li Wu Zhi-gang Que Kai-lang Li School of Metallurgical and Ecological EngineeringUniversity of Science and Technology Beijing Beijing 100083 China

Specularite concentrates have advantages of high ferrous grade, less harmful impurities and low price. However, the small size and poor granulation behavior of specularite concentrates consequently deteriorate the permeability of sinter bed and reduce the productivity of sinter, resulting in un-effective utilization in sintering process. The granulation experiments were carried out when specularite concentrates matched with five kinds of fine or coarse ores, and the effects of surface property and wettability of fine or coarse ores on granulation behavior of specularite concentrates were investigated. Then, the optimized ore blending recipes were proposed to strengthen the granulation behavior of specularite concentrates. The results indicated that the growth index increased with increasing the specific surface area of fine ores and had a positive linear correlation with the circularity degree of coarse ores, whereas negative correlations exist between the growth index and the contact angle of fine or coarse ores. Compared with the concentrates, the growth index increased by approximately 22% scheme of blended ores containing 15 mass% specularite in the case of using Ore-A and Ore-E with greater surface property and higher wettability to replace all of Ore-B and half of Ore-D, respectively. Furthermore, the vertical sintering speed and the productivity of sinter improved by approximately 23% and 20%, respectively.

关键词： Iron ore sinter Granulation behavior Specularite concentrate Surface property Wettability

TEMPO visible light photocatalysis: The selective aerobic oxidation of thiols to disulfides

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Chinese Chemical Letters 2020年第6期31卷 1520-1524页

作者： Hui Xu Yu-Fei Zhang Xianjun lang Sauvage Center for Molecular Sciences College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China

TEMPO(2,2,6,6-tetramethylpipe ridine-1-oxyl)is well-established in orangocatalysis that usually work in synergy with transition-metal catalysis or semiconductor ***,TEMPO was turned into a visible light photocatalyst to conduct the selective aerobic oxidation of thiols into *** O2 as an oxidant,a mild and efficient protocol for the selective oxidation of thiols into disulfides including symmetrical and unsymmetrical ones with 5 mol%of TEPMO as a photocatalyst was developed at room temperature under the irradiation of 460 nm blue *** was found that a complex formed between TEMPO and thiols underpinned the visible light activity and disulfides were obtained in very high isolated *** work suggests that TEMPO takes diverse roles in for photocatalytic selective oxidative transformations with O2 as the oxidant.

关键词： Radical Visible light TEMPO Aerobic oxidation Disulfides

Multiple Emitters Localization by UAV with Nested Linear Array:System Scheme and 2D-DOA Estimation Algorithm

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China Communications 2020年第3期17卷 117-130页

作者： Xinping Lin Xiaofei Zhang lang He Wang Zheng College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211100China Key Laboratory of Dynamic Cognitive System of Electromagnetic Spectrum Space(Nanjing University of Aeronautics and Astronautics) Ministry of Industry and Information TechnologyChina

Unmanned Aerial Vehicle(UAV)equipped with uniform linear array has been applied to multiple emitters ***,nested linear array enables to enhance localization resolution and achieve under-determined Direction of Arrival(DOA)*** this paper,we propose a new system structure for emitters localization that combines the UAV with nested linear array,which is capable of significantly increasing the positioning accuracy of interested ***,a localization scheme is designed to obtain the paired two-dimensional DOA(2D-DOA,*** and elevation angles)estimates of emitters by nested linear array with ***,we propose an improved DOA estimation algorithm for emitters localization that utilizes Discrete Fourier Transform(DFT)method to obtain coarse DOA estimates,subsequently,achieve the fine DOA estimates by sparse *** proposed algorithm has lower computational complexity because the coarse DOA estimates enable to shrink the range of over-complete dictionary of sparse *** addition,compared to traditional uniform linear array,improved 2D-DOA estimation performance of emitters can be obtained with a nested linear *** simulation results testify the effectiveness of the proposed method.

关键词： computational complexity DOA estimation discrete Fourier transform degrees of freedom nested array sparse representation unmanned aerial vehicle

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ASIP编译器设计和实现

电路与系统学报 2009年第6期14卷 59-62,58页

作者：任坤严晓浪孙玲玲浙江大学超大规模集成电路设计研究所浙江杭州310027

为了满足ASIP存储器约束和代码执行的实时性要求,提出一种同时考虑代码选择和寄存器分配的代码综合生成算法,同步处理代码生成的子问题。提出一种能描述ASIP寄存器复杂约束关系的数学模型;改进了传统的图染色算法,将寄存器分配问题转化... 详细信息

为了满足ASIP存储器约束和代码执行的实时性要求,提出一种同时考虑代码选择和寄存器分配的代码综合生成算法,同步处理代码生成的子问题。提出一种能描述ASIP寄存器复杂约束关系的数学模型;改进了传统的图染色算法,将寄存器分配问题转化为对有向数据相关图的简化问题。应用算法构造了一个编译器后端,测试表明,和传统的分步优化算法相比,降低了目标代码的空间尺寸,减少了寄存器溢出的几率。

关键词：专用指令处理器编译器代码生成 ASIP寄存器模型改进图染色算法

High order symplectic conservative perturbation method for time-varying Hamiltonian system

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Acta Mechanica Sinica 2012年第3期28卷 885-890页

作者： Ming-Hui Fu Ke-lang Lu Lin-Hua Lan Department of Applied Mechanics and Engineering Sun Yat-sen University510275 GuangzhouChina

This paper presents a high order symplectic con- servative perturbation method for linear time-varying Hamil- tonian system. Firstly, the dynamic equation of Hamilto- nian system is gradually changed into a high order pertur- bation equation, which is solved approximately by resolv- ing the Hamiltonian coefficient matrix into a ＂major compo- nent＂ and a ＂high order small quantity＂ and using perturba- tion transformation technique, then the solution to the orig- inal equation of Hamiltonian system is determined through a series of inverse transform. Because the transfer matrix determined by the method in this paper is the product of a series of exponential matrixes, the transfer matrix is a sym- plectic matrix; furthermore, the exponential matrices can be calculated accurately by the precise time integration method, so the method presented in this paper has fine accuracy, ef- ficiency and stability. The examples show that the proposed method can also give good results even though a large time step is selected, and with the increase of the perturbation or- der, the perturbation solutions tend to exact solutions rapidly.

关键词： Time-varying Hamiltonian system High ordermultiplicative perturbation Symplectic conservation expo-nential matrix Precise time integration method