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Design and testing of micro fluidic chemical analysis chip integrated with micro valveless pump

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Science China(Technological Sciences) 2005年第3期48卷 326-337页

作者： fu xin xiE Haibo YAng Huayong JIA Zhijian FAng qun State Key Laboratory of Fluid Power Transmission and Control Zhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power Transmission and ControlZhejiang UniversityHangzhou 310027China State Key Laboratory of Fluid Power Transmission and ControlZhejiang UniversityHangzhou 310027China Institute of Microanalytical SystemsZhejiang UniversityHangzhou 310028China Institute of Microanalytical SystemsZhejiang UniversityHangzhou 310028China

A new structure and working principle of the chip integrated with micro valveless pump for capillary electrophoresis was proposed in this paper. The micro valveless pump with plane structure has advantages of simple structure, and the process technology is compatible with existing micro chips for capillary electrophoresis. Based upon the mathematical model, simulation study of micro pump was carried out to investigate the influence of structural parameters on flow characteristics, and the performance of the integrated micro pump was also tested with different control parameters. The simulation results agree with the experimental results. Three samples, which are amino acid, fluorescein and buffer solution, have been examined with this chip. The results of the primary experiments showed that the micro valveless pump was promising in the integration and automatization of miniature integrated fluidic systems.

关键词： MEMS,micro valveless pump,micro fluidic chip,CFD,capillary electrophoresis.

Neutron Stars in the Model of Non—linear Realization of SU（2） Chiral Symmetry Spontaneous Breaking

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Communications in Theoretical Physics 2003年第5期39卷 603-606页

作者： WAngNan SUNBao-xi LUExiao-fu ZHAOEn-Guang InstituteofTeorticalphysics theChineseAcademyofSciencesBeijing100080China InstituteofHighEnergyPhysics theChineseAcademyofSciencesP.O.Box918(4)Beijing100039China InstituteofTeorticalphysics theChineseAcademyofSciencesBeijing100080China DepartmentofPhysics SichuanuniversityChengdu610064China InstituteofTeorticalphysics theChineseAcademyofSciencesBeijing100080China CenterofTheoreticalNuclearPhysics NationalLaboratoryofHeavyIonAcceleratorLanzhou730000CHina DepartmentofPhysics TsinghuaUniversityBeijing1

The properties of neutron stars are studied in a relativistic mean-field model with SU(2) chiral symmetry spontaneous breaking being considered. The calculation results indicate that the effects of the chiral symmetry... 详细信息

关键词： neutron star chiral symmetry spontaneous breaking relativistic mean-field approximation

Protection of Metasequoia glyptostroboides Hu et Cheng in China

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Forestry Studies in China 2009年第4期11卷 249-257页

作者： WAng xi-qun GUO Bao-xi.ng Planning and Design Academy of Forest Products Industry State Forestry Administration Beijing 100010 P. R. China

Metasequoia （Metasequoia glyptostroboides Hu et Cheng） is an important but endangered tree species. In a sense, the course of protection of the metasequoia can be considered a miniature of the history of the protection of rare Chinese plants over the past 50 years. The approval and establishment of the National Class Nature Reserve for metasequoia is a milestone in this course. A thorough understanding of this course is beneficial to design the correct future protection plans and for taking effective measures. In this paper the entire protection course of metasequoia is reviewed, three detailed measures are proposed according to the present situation and existing problems and discussed as follows. 1） We should reinforce unceasingly the establishment of National Nature Reserves of metasequoia, put emphasis on the protection of the original natural mother trees （ONMTs） of metasequoia, design far- sighted projects to protect the ONMTs and strictly implement and enforce the regulations or laws regarding the protection of meta- sequoia. The establishment and functions of the organization should meet the demands of protecting the ONMTs and developing metasequoias. The budget should support and the quality of the personnel assigned to this task should satisfy the protection and de- velopment of the ONMTs. We should also promote the complete protection of the ONMTs at the same time and strengthen the pro- tection and restoration of the ONMTs and their ecosystem in the xiaohe valley, Lichuan County, Hubei Province, one of the natural concentration areas of ONMTs in the world. 2） A gene bank should be established for comprehensive protection of the genes of ex- isting original mother trees of metasequoia. 3） The key is to study the theoretical fundamentals of restoration and re-establishment of natural vegetation of metasequoia in the xiaohe valley to harmonize the relation among environmental departments, forestry sectors, academies of sciences and other educational or resea

关键词： Metasequoia glyptostroboides Hu et Cheng original mother trees protection course existing problems

A new flow stress model based on Arrhenius equation to track hardening and softening behaviors of Ti6Al4V alloy

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Rare Metals 2018年第12期37卷 1035-1045页

作者： fu-Hui Zhu Wei xi.ng xi-Feng Li Jun Chen Department of Plasticity Technology Shanghai Jiao Tong University

The conventional Arrhenius-type model was adopted to identify the deformation characteristic of Ti6 A14 V(TC4) titanium alloy based on the stress-strain curves of isothermal compression test. A new flow stress model based on Arrhenius equation was proposed for TC4,which is composed of peak flow stress(PFS) prediction and strain compensation. The predicted PFS is set as a reference to derive the flow stress model at any strain ranging from approximately 0 to 0.7. The predictability and efficiency among the proposed model, conventional model,and an existing physical-based model of TC4 were comparatively evaluated. It is found that the newly proposed model can simultaneously track the hardening and softening behaviors of TC4 through a single expression while the other existing models are only valid in the softening ***, the wider application range and acceptable accuracy of the new model have been achieved by fewer material constants with much-simplified modeling procedure than the other models.

关键词： Flow stress model Arrhenius equation Hot deformation Flow behavior Titanium alloy

Vertical α-FeOOH nanowires grown on the carbon fiber paper as a free-standing electrode for sensitive H2O2 detection

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Nano Research 2016年第8期9卷 2260-2269页

作者： Shichao Du Zhiyu Ren Jun Wu Wang xi Honggang fu Institute of Theoretical chemistry Jilin University ChangChun 130023 China Key Laboratory of functional Inorganic Material Chemistry Ministry of Education of the People's Republic of China School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

Highly sensitive, selective, and stable hydrogen peroxide （H2O2） detection using nanozyme-based catalysts are desirable for practical applications. Herein, vertical α-FeOOH nanowires were successfully grown on the surface of carbon fiber paper （CFP） via a low-temperature hydrothermal procedure. The formation of vertical α-FeOOH nanowires is ascribed to the structure-directing role of sodium dodecyl sulfate. The resulting free-standing electrode with one-dimensional （1D） nanowires offers oriented channels for fast charge transfer, excellent electrical contact between the electrocatalyst and the current collector, and good mechanical stability and reproducibility. Thus, it can serve as an efficient electrocatalyst for the reduction and sensitive detection of H2O2. The relation of the oxidation current of H202 with the concentration is linear from 0.05 to 0.5 mM with a sensitivity of -0.194 mA/（***2） and a low detection limit of 18μM. furthermore, the portability in the geometric tailor and easy device fabrication allow extending the general applicability of this free-standing electrode to chemical and biological sensors.

关键词： α-FeOOH nanowires free-standing electrode synergistic effect electrocatalysis H2O2 detection

Efficient Processing of Skyline Group Queries over a Data Stream

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Tsinghua Science and Technology 2016年第1期21卷 29-39页

作者： xi Guo Hailing Li Aziguli Wulamu Yonghong xie Yajing fu Beijing Key Laboratory of Knowledge Engineering for Materials Science University of Science and Technology Beijing

In this paper, we study the skyline group problem over a data stream. An object can dominate another object if it is not worse than the other object on all attributes and is better than the other object on at least one attribute. If an object cannot be dominated by any other object, it is a skyline object. The skyline group problem involves finding k-item groups that cannot be dominated by any other k-item group. Existing algorithms designed to find skyline groups can only process static data. However, data changes as a stream with time in many applications,and algorithms should be designed to support skyline group queries on dynamic data. In this paper, we propose new algorithms to find skyline groups over a data stream. We use data structures, namely a hash table, dominance graph, and matrix, to store dominance information and update results incrementally. We conduct experiments on synthetic datasets to evaluate the performance of the proposed algorithms. The experimental results show that our algorithms can efficiently find skyline groups over a data stream.

关键词： skyline skyline group data streams query processing

Comparative investigation on high-speed grinding of TiCp/Ti–6Al–4V particulate reinforced titanium matrix composites with single-layer electroplated and brazed CBN wheels

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Chinese Journal of Aeronautics 2016年第5期29卷 1414-1424页

作者： Li Zheng Ding Wenfeng Shen Long xi xinxin fu Yucan College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and Astronautics

In order to develop the high-efficiency and precision machining technique of TiCp/Ti - 6Al-4V particulate reinforced titanium matrix composites （PTMCs）, high-speed grinding experiments were conducted using the single-layer electroplated cubic boron nitride （CBN） wheel and brazed CBN wheel, respectively. The comparative grinding performance was studied in terms of grinding force, grinding temperature, grinding-induced surface features and defects. The results display that the grinding forces and grinding temperature obtained with the brazed CBN wheel are always lower than those with the electroplated CBN wheel. Though the voids and microcracks are the dominant grinding-induced surface defects, the brazed CBN wheel produces less surface defects compared to the electroplated wheel according to the statistical analysis results. The max mum materials removal rate with the brazed CBN wheel is much higher than that with the electroplated one. All above indicate that the single-layer brazed CBN super-abrasive wheel is more suitable for high-speed grinding of PTMCs than the electroplated counterpart.

关键词： High-speed grinding PTMCs Single-layer brazed CBNwheel Single-layer electroplated CBN wheel Surface defects

Microbe social skill:the cell-to-cell communication between microorganisms

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Science Bulletin 2017年第7期62卷 516-524页

作者： xi Zhao xi.ng Liu xin Xu Yu V.fu State Key Laboratory of Microbial Resources Institute of MicrobiologyChinese Academy of Sciences Savaid Medical School University of Chinese Academy of Sciences

Although microbes primarily are single-cell organisms,they are not isolated *** use various means to communicate with one *** on the communication,microbes establish a social interaction with their neighbors in a specific ecological niche,and cooperative behaviors are normally performed to provide benefits on the population and species *** the microbiome era,in order to better understand the behaviors of microbes,deep understanding of the social communication between microbes hence becomes a key to interpret microbe *** we summarize the molecular mechanisms that underlie the cell-to-cell communication in prokaryotic and eukaryotic microorganisms,the recent discoveries and novel technologies in understanding the interspecies and interkingdom communication,and discuss new concepts of the sociomicrobiology.

关键词： Cell-to-cell communication Sociomicrobiology Microbial collective behavior Quorum sensing

Synthesis of a new 2,2':6',2''-terpyridine derivative and its coordination property

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Chinese Chemical Letters 2007年第5期18卷 530-532页

作者： Yong Chen xi Juan Zhao Jun Feng Zhang Wen fu fu Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate University of Chinese Academy of Sciences Beijing 100039 China College of Chemistry and Chemical Engineering Yunnan Normal University Kunming 650092 China

A novel compound, （E）-4′-（4-（but-1-en-3-ynyl）phenyl）-2,2′：6′,2″-terpyridine 1 was synthesized from 4′-（4-bromomethylphenyl）-2,2P：6P,2PP-terpyridine phosphonium salt 2 and propargylaldehyde via Wittig reaction, and characterized by EI-MS and ^1H NMR as well as elemental analysis. The spectral changes of the compound in the presence of transition metal ions, such as Cu（I） or Zn（ID, are investigated.

关键词： Polypyridine ligands Synthesis Coordination