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Synchronization in Oscillator Networks with Nonlinear Coupling

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Communications in Theoretical Physics 2008年第10期50卷 925-930页

作者： zhang jian-bao LIU Zeng-Rong LI Ying School of Sciences Hangzhou Dianzi University Hangzhou 310018 China Institute of Systems Biology Shanghai University Shanghai 200444 China College of Sciences Shanghai University Shanghai 200444 China

Synchronization in coupled oscillator networks has attracted much attention from many fields of science and engineering. In this paper, it is firstly proved that the oscifiator network with nonlinear coupling is also eventually dissipative under the hypothesis of eventual dissipation of the uncoupled oscillators. And the dynamics of the network is analyzed in its absorbing domain by combining two methods developed recently. Suufficient conditions for synchronization in the oscillator networks with nonlinear coupling are obtained. The two methods are combined effectively and the results embody the respective merits of the two methods. Numerical simulations confirm the validity of the results.

关键词： complete synchronization nonlinear coupling Lyapunov function approach

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考虑电动汽车参与的配电网经济运行模型研究

制造业自动化 2024年第2期46卷 147-153页

作者：魏联滨张保健王彬范瑞卿张金华国网天津市电力公司天津300010 国网天津武清公司天津301700

随着能源需求的日益增长以及风电并网比例的提高,如何协调电力系统中源-网-荷之间的协调互动显得越发困难,因此提出一种考虑电动汽车参与的配网经济运行模型。首先,利用电力系统中的“非同调”现象作为电网结构优化的理论基础,对配网结... 详细信息

随着能源需求的日益增长以及风电并网比例的提高,如何协调电力系统中源-网-荷之间的协调互动显得越发困难,因此提出一种考虑电动汽车参与的配网经济运行模型。首先,利用电力系统中的“非同调”现象作为电网结构优化的理论基础,对配网结构进行优化;然后,在负荷侧考虑电动汽车的可调度性,采用需求响应调整充电负荷,协助消纳风电出力;最后,以系统运行成本最小为目标建立网-荷协同配网经济运行模型。仿真结果表明:通过对配网结构进行优化有助于提高系统的经济性,需求响应引导电动汽车有序调整充电负荷有助于风电出力消纳,网-荷协调更有利于提高系统运行的经济性以及供电可靠性。

关键词：电动汽车风电需求响应 “非同调”现象调度优化

Attaining synergetic equilibrium of electrical conductivity and tensile strength in GQDs@GN/Cu composites through multi-scale intragranular and intergranular reinforcements

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Rare Metals 2024年第1期43卷 366-379页

作者： Shuang-Yin zhang Liang Liu Rui bao jian-Hong Yi Sheng-Da Guo Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Advanced Materials of Yunnan Province Kunming University of Science and TechnologyKunming 650093China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China

The configuration and quality of reinforcements, as well as the robustness of interfacial bonding,holding a critical significance in determining the concurrence between electrical conductivity and mechanical strength in metal matrix composites. In this study, citric acid was employed as the precursor for synthesizing multiscale carbon nanomaterials(graphene quantum dots and graphene, abbreviated as GQDs and GN). The GQDs@GN/Cu composites were fabricated through a segmented ball milling process in conjunction with subsequent spark plasma sintering(SPS). The intragranular GQDs and intergranular GQDs@GN had synergistically reinforced Cu composites through Orowan strengthening, load transfer strengthening and refinement strengthening. Furthermore,the robust interface bonding between GQDs@GN and Cu effectively mitigated interfacial impedance stemming from electron-boundary scattering. The yield strength and ultimate tensile strength of the GQDs@GN/Cu composites were recorded as 270 and 314 MPa, respectively, representing an improvement of 92 and 28% over pure Cu, while maintaining electrical conductivity at a level comparable to that of pure Cu. This study advances the understanding of the possibility of realizing a synergistic compatibility between electrical conductivity and mechanical strength in Cu composites.

关键词： Cu matrix composites Interface bonding Mechanical property Graphene quantum dots(GQDs) Electrical conductivity

Apoptosis of human pancreatic cancer cells induced by Triptolide

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World Journal of Gastroenterology 2008年第10期14卷 1504-1509页

作者： Guo-Xiong Zhou Xiao-Ling Ding Jie-Fei Huang Hong zhang Sheng-bao Wu jian-Ping Cheng Qun Wei Department of Gastroenterology Affiliated Hospital of Nantong University Nantong 226001 Jiangsu Province China

AIM: To investigate apoptosis in human pancreatic cancer cells induced by Triptolide (TL), and the relationship between this apoptosis and expression of caspase-3' bcl-2 and bax. METHODS: Human pancreatic cancer cell line SW1990 was cultured in DMEM media for this study. MTT assay was used to determine the cell growth inhibitory rate in vitro. Flow cytometry and TUNEL assay were used to detect the apoptosis of human pancreatic cancer cells before and after TL treatment. RT-PCR was used to detect the expression of apoptosis-associated gene caspase-3' bcl-2 and bax. RESULTS: TL inhibited the growth of human pancreatic cancer cells in a dose-and time-dependent manner. TL induced human pancreatic cancer cells to undergo apoptosis with typically apoptotic characteristics. TUNEL assay showed that after the treatment of human pancreatic cancer cells with 40 ng/mL TL for 12 h and 24 h, the apoptotic rates of human pancreatic cancer cells increased significantly. RT-PCR demonstrated that caspase-3 and bax were significantly up-regulated in SW1990 cells treated with TL while bcl-2 mRNA was not. CONCLUSION: TL is able to induce the apoptosis in human pancreatic cancer cells. This apoptosis may be mediated by up-regulating the expression of apoptosis- associated caspase-3 and bax gene.

关键词： Triptolide Pancreatic cancer Apoptosis Bcl-2 Caspase-3 Bax

Permanent lining castable with low bulk density and thermal conductivity:bauxite castable for tundish obtained by adding pearlescent sand

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Journal of Iron and Steel Research International 2024年第3期31卷 634-646页

作者： Yi Wang jian Yang bao Wang Hai-jun zhang Juan Han Pei-yan Pei Wen-long Lv jian-an Zhou The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Wuhan Research Institute of Metallurgical Construction MCCWuhan 430081HubeiChina

The low thermal conductivity and light mass of castables for tundish permanent linings are crucial for minimizing the heat loss of molten *** consideration of the low bulk density and thermal conductivity of pearlescent sand,the thermal insulation performance of castables was attempted to be improved by adding pearlescent *** sand was modified to prevent the strength of its porous structure from *** modification mechanism of pearlescent sand and the effect of pearlescent sand on the performance of bauxite castables were *** results suggested that the addition of the modified pearlescent sand significantly raised the apparent porosity and decreased the bulk density of bauxite *** 1000℃,the bulk density of more than 60%of the modified pearlescent sand-bauxite castable was only 2.03 g/cm^(3).The mechanical properties and thermal shock resistance of the modified pearlescent sand-bauxite castable were inferior to those of conventional bauxite castable but were adequate to meet the use conditions of casta-bles for tundish permanent *** high temperatures of 200-800℃,the thermal conductivity of more than 60%of the modified pearlescent sand-bauxite castable was smaller than that of conventional bauxite *** addition of the modified pearlescent sand can greatly reduce the thermal conductivity and bulk density of bauxite castable.

关键词： Pearlescent sand-Hydrophobic modification Bauxite castable Thermal insulation performance Mechanical property

Researches　into　the　Proton　Conductivity　of　Molybdovanadophosphoric　Acids　with　Wells－Dawson　Structure

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Chemical Research in Chinese Universities 1996年第4期12卷 322-325页

作者： WANG En-bo LI Bai-tao WANG Zuo-ping and zhang bao-jian(Department of Chemistry,Northeast Normal University,Changchun,130024) NE NORMAL UNIV DEPT CHEMCHANGCHUN 130024PEOPLES R CHINA

Five kinds of molybdovanadophosphoric acids H_7[P_2Mo_(17)VO_(62)],H_8[P_2Mo_(16)·V_2O_(62)],H_9 [P_2Mo_(15)V_3O_(62)],H_8[P_2Mo_(14)V_4O_(61)(H_2O)]and H_9[P_2Mo_(13)V_5O_(61)(H_2O)]have been *** protop conductivities(C) have been *** effects of three main factors (frequency,hydration numbers,temperature)on the conductivity have been *** some degree,heteropoly compounds with different structures give a different conductivity.

关键词： s:Proton conductivity Heteropoly acid Polarization Molyb dovanadophosphoric acid

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： Yang Lu jian-Xin Deng Zhi-Hui zhang Jia-Xing Wu Ran Wang Yi-Chen bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1%,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

Concerted Steric and Electronic Strategy in Thermostable Salicylaldiminato Nickel Catalysts for Ethylene(Co)polymerization

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Chinese Journal of Polymer Science 2024年第8期42卷 1085-1092页

作者： Hong-Yu Ji Hong-Liang Mu Chun-Feng Tang Yu-Xing zhang Yue Chi Zhong-bao jian Key Laboratory of Advanced Structural Materials Ministry of EducationSchool of Materials Science and EngineeringChangchun University of TechnologyChangchun 130012China State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

Olefin polymerization is one of the most im portant chemical reactions in *** work presents a strategy that emphasizes the synergistic meta/poro-steric hindrance of N-aryl groups and electronic effects in newly synthesized neutral salicylaldiminato nickel *** nickel(Ⅱ)catalysts exhibit exceptional thermostability,ranging from 30℃to 130℃,demonstrating enhanced catalytic activities and broadly regulated polyethylene molecular weights(3-341 kg·mol^(-1))and controlled polymer branch density(2-102 brs/1000C).The preferred catalyst Ni3 with concerted steric and electronic effects enables the production of solid-state semi-crystalline polyethylene materials at temperatures below 90℃.Notably,Ni3 exhibits an impressive tolerance of 110℃and can withstand even the challenging polymerization temperature of 130℃,leading to the production of polyethylene wax and ***,functionalized polyethylene is produced.

关键词： Polyolefin Salicylaldiminato ligand Nickel catalyst Oil Wax

A novel weld-pool-length monitoring method based on pixel analysis in plasma arc additive manufacturing

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Advances in Manufacturing 2024年第2期12卷 335-348页

作者： bao-Ri zhang Yong-Hua Shi Bionic Robot Research Department Ji Hua LaboratoryFoshan528200GuangdongPeople’s Republic of China Guangdong Provincial Engineering Research Center for Special Welding Technology and Equipment School of Mechanical and Automotive EngineeringSouth China University of TechnologyGuangzhou510640People’s Republic of China

The real-time monitoring of the weld pool during deposition is important for automatic control in plasma arc additive *** obtain a high deposition accuracy,it is essential to maintain a stable weld pool *** this study,a novel passive visual method is proposed to measure the weld pool *** the proposed method,the image quality was improved by designing a special visual system that employed an endoscope and a *** also includes pixel brightness-based and gradient-based algorithms that can adaptively detect feature points at the boundary when the weld pool geometry *** algorithm can also be applied to materials with different solidification *** was performed to measure the real weld pool length in world coordinates,and outlier rejection was performed to increase the accuracy of the ***,tests were carried out on the intersection component,and the results showed that the proposed method performed well in tracking the changing weld pool length and was applicable to the real-time monitoring of different types of materials.

关键词： Plasma arc additive manufacturing(PAAM) Weld pool geometry Gradient analysis Real-time detection