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    题名 作者 年代 出处 被引量
1Flexible unsmoothed cuticles of soil animals and their characteristics of reducing adhesion and resistance显示文摘Based on observing and analyzing the typical soil animals, the flexible unsmoothness is defined, which is the moving unsmoothness made by the flexible deformation of the structural units, and its characteristics of reducing adhesion and resistance is analyzed. The tests show that on the same conditions, compared with 45 Steel, the adhesion of the field_mouse’s fur is reduced by about 35%, its sliding resistance is reduced by about 80%.Luquan Ren Yunpeng Wang Jianqiao Li Jin Tong 1998Chinese Science Bulletin1998,43,2:26
2Hybrid Material of Graphene and Poly(3,4-ethyldioxythiophene)with High Conductivity,Flexibility,and Transparency显示文摘A novel hybrid material prepared from graphene and poly(3,4-ethyldioxythiophene)(PEDOT)shows excellent transparency,electrical conductivity,and good flexibility,together with high thermal stability and is easily processed in both water and organic solvents.Conductivities of the order of 0.2 S/cm and light transmittance of greater than 80%in the 4001800 nm wavelength range were observed for fi lms with thickness of tens of nm.Practical applications in a variety of optoelectronic devices are thus expected for this transparent and flexible conducting graphene-based hybrid material。Yanfei Xu Yan Wang Jiajie Liang Yi Huang Yanfeng Ma Xiangjian Wan Yongsheng Chen 2009Nano Research2009,2,4:23
3Prevalence of physical fitness in Chinese school-aged children: Findings from the 2016 Physical Activity and Fitness in China -The Youth Study显示文摘Purpose: This study was to present the 2016 prevalence estimates of Chinese school-aged children meeting physical fitness standards and to examine differences by sex and residence locales in children who did not meet fitness standards.Methods: We conducted cross-sectional analyses of 171,991 children and adolescents(boy: 50.0%, Grades 1–12) who participated in the 2016 Physical Activity and Fitness in China—The Youth Study. The main outcomes were fitness measures, assessed by the 2014 revised Chinese National Student Physical Fitness Standard(CNSPFS), covering areas of aerobic capacity, upper body strength, flexibility, body mass index,abdominal strength, and trunk strength. Children's overall physical fitness performance was categorized, per CNSPFS standards, as excellent,good, pass, or no pass. Data on the prevalence of physical fitness categories and not meeting fitness standards(i.e., among children who received a 'no pass' mark) were analyzed, through logistic regression, by sex(boy, girl) and residence locales(urban, rural) across 3 school grades(primary,junior middle, and junior high).Results: In 2016, 5.95% of Chinese children and adolescents achieved an 'excellent' mark, 25.80% received a 'good' rating, 59.90% received a 'pass', and 8.35% received a 'no pass'. Overall, boys were more likely to not pass the fitness standards compared with girls(adjusted odds ratio(a OR) = 1.710; 95% confidence interval(CI): 1.708–1.712) and children living in urban areas were more likely to not pass the standards than those living in rural areas(a OR = 1.298; 95%CI: 1.296–1.299). Consistent patterns of not meeting fitness standards were also found by sex and residence locales across all 3 school grades.Conclusion: In the Chinese school-aged population, about 3 in 10 children achieved an 'excellent' or 'good' fitness standard in 2016, and about8% of this population did not meet CNSPFS standards. Children living in urban areas were more likely to not meet minimum fitness performance levels, and boys in school were more likely to not meet minimum fitness performance levels than girls.Zheng Zhu Yang Yang Zhenxing Kong Yimin Zhang Jie Zhuang 2017Journal of Sport and Health Science2017,6,4:16
4NiCoO2/NiCoP@Ni nanowire arrays:tunable composition and unique structure design for high-performance winding asymmetric hybrid supercapacitors显示文摘Transition metal phosphides(TMPs)are recognized as such promising supercapacitor materials for the practical application,due to their superior electrical conductivity and excellent redox activity.Here,self-supported three-dimensional NiCoP nanoparticles embedded in NiCoO2 nano wires(NiCoO2/NiCoP)electrode consisting of nickel cobalt phosphides(NiCoP)with high activity and nickel cobalt oxides(NiCoO2)with good stability were fabricated by a hydrothermal and phosphorization method.The electrode integrates the advantages of nanowire arrays for fast ion transport and foam Ni for effective charge transport and flexibility.Benefitting the proper composition control of the nanohybrid and unique structure design,the optimized NiCoO2/NiCoP-20 exhibits a high specific capacitance of 3204 F·g-1 at 1 A·g-1 in 3 mol·L-1 KOH aqueous electrolyte in a three-electrode system.Moreover,the asymmetric supercapacitor assembled with the prepared NiCoO2/NiCoP-20 and activated carbon achieves a specific capacitance of 116 F·g-1 with a high energy density of 40.32 Wh·kg-1 at the power density of 800.18 W·kg-1.The practical application is further demonstrated with all-solid-state winding supercapacitor devices,with decent flexibility,in series to light the Central South University(CSU)logo consisting of 21 red LED indicators.Wei-Wei Ning Li-Bao Chen Wei-Feng Wei Yue-Jiao Chen Xiao-Yong Zhang 2020Rare Metals2020,39,9:12
5Flexible and transparent graphene/silver-nanowires composite ?lm for high electromagnetic interference shielding effectiveness显示文摘Herein, an efficient approach to prepare flexible, transparent, and lightweight films based on graphene nanosheets(GNS) and silver nanowires(AgNWs) for high electromagnetic interference(EMI) shielding effectiveness(SE) has been explained. High-conductive GNS were fabricated by liquid phase stripping and composited with AgNWs by a two-step spin-coating method. Owing to the high transparency, good conductivity, and homogeneous distribution of both GNS and AgNWs, the obtained GNS/AgNWs film exhibits superb EMI SE and light transmittance, yielding a significantly high EMI SE up to 26 dB in both Ku-band and K-band and light transmittance higher than 78.4%. Moreover, this GNS/AgNWs film shows good flexibility and excellent structural stability. The obtained flexible, light and transparent film could have a great potential for transparent EMI shielding and smart electronics.Ning Zhang Zhe Wang Rongguo Song Qianlong Wang Hongye Chen Bin Zhang Haifei Lv Zhi Wu Daping He 2019Science Bulletin2019,64,8:12
6Controlling flexibility of metal–organic frameworks显示文摘Framework flexibility is one of the most important characteristics of metal–organic frameworks(MOFs),which is not only interesting, but also useful for a variety of applications. Designing, tailoring or controlling framework flexibility of MOFs is much more difficult than for static structural features such as the framework topology and pore size/shape. Nevertheless, with in-depth understanding of the relationship between framework flexibility and the host framework structure, guest loading and other aspects such as the crystal size/morphology and external physical environment, some strategies have been developed for controlling the flexibility of MOFs and the corresponding properties, which are summarized and discussed in this review.Jie-Peng Zhang Hao-Long Zhou Dong-Dong Zhou Pei-Qin Liao Xiao-Ming Chen 2018National Science Review2018,5,6:10
7Stratum energy of coal-bed gas reservoir and their control on the coal-bed gas reservoir formation显示文摘Stratum energy of coal-bed gas reservoir, including coal-radix flexibility energy, groundwater flexibility energy and gas flexibility energy (hereinafter 'three energy'), depends on the energy homeostasis system, the core process of which is the effective transfer of energy and the geological selective process. Combining with the mechanics experimentations of coal samples, different flexibility energy has been analyzed and researched quantificationally, and a profound discussion to their controls on the coal-bed gas reservoir formation has been made. It is shown that when gas reservoir is surrounded by edge water and bottom water, the deposited energy in the early phase of forming gas reservoir is mostly coal-radix and gas flexibility energy, but the effect of groundwater flexibility energy increases while water-body increases. The deposited energy in the middle and later phase of forming gas reser voir is mostly gas flexibility energy, which is greater than 80% of all deposited energy. In the whole process, larger groundwater body exerts greater influences on gas accumulation. The paper indicated that higher stratum energy is more propitious to forming coal-bed gas reservoir. And higher coal-radix flexibility energy and gas flexibility energy are more propitious to higher yield of gas reservoirs, while higher groundwater flexibility energy is more propitious to stable yield of gas reservoirs. Therefore, the key to evaluating the coal-bed gas reservoir formation is the stratum energy of coal-bed gas reservoir.WU CaiFang QIN Yong FU XueHai 2007Science China Earth Sciences2007,50,9:9
8Adaptive Resources Allocation Algorithm Based on Modified PSO for Cognitive Radio System显示文摘Radio spectrum has become a rare resource due to the rapid development of wireless communication technique. Cognitive radio is one of important techniques to deal with this radio spectrum problem. But the resource allocation in cognitive radio also has its own issues, such as the flexibility of the allocation algorithm, the performance of resource allocation, and so on. In order to increase the flexibility of the allocation algorithm for cognitive radio, more and more researches are focusing on the evolutionary algorithms, such as genetic algorithm(GA), particle swarm optimization(PSO). Evolutionary algorithm can greatly improve the flexibility of the allocation algorithm for cognitive radio system in different communication scenarios, but the performances are relatively lower than the original mathematical methods. So in this paper, we proposed an adaptive resource allocation algorithm based on modified PSO for cognitive radio system to solve these problems. Modified particle swarm optimization(Modified PSO) has both genetic algorithm(GA) and particle swarm optimization(PSO)’s updating processes which makes this modified PSO overcame PSO’s own disadvantages and keep advantages. Simulation results showed our proposed algorithm has enough flexibility to meet cognitive radio systems’ requirements, and also has a better performance than original PSO.Yi Yang Qinyu Zhang Ye Wang Takahiro Emoto Masatake Akutagawa Shinsuke Konaka 2019China Communications2019,16,5:9
9Damage localization under ambient vibration using changes in flexibility显示文摘In recent years, Structural Health Monitoring (SHM) has emerged as a new research area in civil engineering. Mostexisting health monitoring methodologies require direct measurement of input excitation for implementation. However, in manycases, there is no easy way to measure these inputs - or alternatively to externally excite the structure. Therefore, SHM methodsbased on ambient vibration have become important in civil engineering. In this paper, an approach is proposed based on the DamageLocation Vector (DLV) method to handle the ambient vibration case. Here, this flexibility-matrix-based damage localization methodis combined with a modal expansion technique to eliminate the need to measure the input excitation. As a by-product of thisapproach, in addition to determining the location of the damage, an estimate of the damage extent also can be determined. Finally, anumerical example analyzing a truss structure with limited sensors and noisy measurement is provided to verify the efficacy of theproposed approach.高勇 苏磐石 2002Earthquake Engineering and Engineering Vibration2002,1,1:9
10Perfect teleportation of an arbitrary three-qubit state with the highly entangled six-qubit genuine state显示文摘The perfect teleportation of an arbitrary three-qubit state with the highly entangled six-qubit genuine state introduced by Borras et al.(J.Phys.A: Math.Theor.40 (2007) 13407) is studied.Some appropriate measuring bases the sender can take and the corresponding unitary operations the receiver should execute in terms of the sender’s measurement outcome are explicitly given.The flexibility between the measurement difficulty and the reconstruction difficulty is shown.Moreover,discussions and comparisons between our scheme and the recent incomplete scheme (Choudhury et al,J.Phys.A: Math.Theor.42 (2009) 115303) are made.YIN XiaoFeng 1,LIU YiMin 2,ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education of China,School of Physics & Material Science,Anhui University,Hefei 230039,China 2 Department of Physics,Shaoguan University,Shaoguan 512005,China 2010Science China(Physics,Mechanics & Astronomy)2010,53,11:7
11A Perspective on Smart Process Manufacturing Research Challenges forProcess Systems Engineers显示文摘The challenges posed by smart manufacturing for the process industries and for process systems engineering(PSE) researchers are discussed in this article. Much progress has been made in achieving plant- and site-wide optimization, hut benchmarking would give greater confidence. Technical challenges confrontingprocess systems engineers in developing enabling tools and techniques are discussed regarding flexibilityand uncertainty, responsiveness and agility, robustness and security, the prediction of mixture propertiesand function, and new modeling and mathematics paradigms. Exploiting intelligence from big data to driveagility will require tackling new challenges, such as how to ensure the consistency and confidentiality ofdata through long and complex supply chains. Modeling challenges also exist, and involve ensuring that allkey aspects are properly modeled, particularly where health, safety, and environmental concerns requireaccurate predictions of small but critical amounts at specific locations. Environmental concerns will requireus to keep a closer track on all molecular species so that they are optimally used to create sustainablesolutions. Disruptive business models may result, particularly from new personalized products, but that isdifficult to predict.Ian David Lockhart Bogle 2017Engineering2017,3,2:7
12Progress and prospects of innovative coal-fired power plants within the energy internet显示文摘The development of electrical engineering and electronic, communications, smart power grid, and ultra-high voltage transmission technologies have driven the energy system revolution to the next generation: the energy internet. Progressive penetration of intermittent renewable energy sources into the energy system has led to unprecedented challenges to the currently wide use of coal-fired power generation technologies. Here, the applications and prospects of advanced coal-fired power generation technologies are analyzed. These technologies can be summarized into three categories:(1) large-scale and higher parameters coal-fired power generation technologies, including 620/650/700 oC ultra-supercritical thermal power and double reheat ultra-supercritical coal-fired power generation technologies;(2) system innovation and specific, highefficiency thermal cycles, which consist of renewable energy-aided coal-fired power generation technologies, a supercritical CO_2 Brayton cycle for coal-fired power plants, large-scale air-cooling coal-fired power plant technologies, and innovative layouts for waste heat utilization and enhanced energy cascade utilization;(3) coal-fired power generation combined with poly-generation technologies, which are represented by integrated gasification combined cycle(IGCC) and integrated gasification fuel cell(IGFC) technologies. Concerning the existing coal-fired power units, which are responsible for peak shaving, possible strategies for enhancing flexibility and operational stability are discussed. Furthermore, future trends for coal-fired power plants coupled with cyber-physical system(CPS) technologies are introduced. The development of advanced, coal-fired power generation technologies demonstrates the progress of science and is suitable for the sustainable development of human society.Yongping Yang Chengzhou Li Ningling Wang Zhiping Yang 2019Global Energy Interconnection2019,2,2:7
13Integrated Energy Production Unit: An Innovative Concept and Design for Energy Transition Toward Low-carbon Development显示文摘To achieve the goals of emission peak and carbon neutrality,significant effort is invested to accelerate the energy transition,with a focus on the development and utilization of renewable energy,as well as the upgrading of conventional units.Within this context,this paper proposes an innovative concept,known as the integrated energy production unit(IEPU),providing a variety of energy products and flexible adjustment functions for power systems with high penetration of non-hydro renewable energy.In the IEPU framework,a photovoltaic(PV)power plant is installed to produce electricity;CO_(2) capture technology is applied to the existing coal-fired power plant with biomass co-combustion.The generated CO_(2) is used to synthesize methane or methanol with hydrogen through electrolysis.First,the operational principle and advantages of this concept are illustrated.Then,a simplified model is built to provide an optimal configuration scheme of equipment capacity.Finally,the potential contribution of IEPU to the operational flexibility of the power system is also analyzed.Xiaoxin Zhou Qiang Zhao Yuqiong Zhang Li Sun 2021CSEE Journal of Power and Energy Systems2021,7,6:7
14Towards Fully Renewable Energy Systems:Experience and Trends in Denmark显示文摘Deployment of renewable energy generation capacities and integration of their power production into existing power systems has become a global trend,with a common set of operational challenges stemming from variability and limited predictability of power generation from,e.g.,wind and solar.Denmark is a country that invested early in wind energy,rapidly proposing very ambitious goals for the future of its energy system and global energy usage.While the case of Denmark is specific due to its limited size and good interconnections,there may still be a lot to learn from the way operational practice has evolved,also from shifting towards a liberalized electricity market environment,and more generally from going along with other technological and societal evolution.The aim of this paper is to give an overview of recent and current initiatives in Denmark that contributes towards a goal of reaching a fully renewable energy system.Pierre Pinson Lesia Mitridati Christos Ordoudis JacobØstergaard 2017CSEE Journal of Power and Energy Systems2017,3,1:7
15Self-propulsion of flapping bodies in viscous fluids: Recent advances and perspectives显示文摘Flapping-powered propulsion is used by many animals to locomote through air or water. Here we review recent experimental and numerical studies on self-propelled mechanical systems powered by a flapping motion. These studies improve our understanding of the mutual interaction between actively flapping bodies and surrounding fluids. The results obtained in these works provide not only new insights into biolocomotion but also useful information for the biomimetic design of artificial flyers and swimmers.Shizhao Wang Guowei He Xing Zhang 2016Acta Mechanica Sinica2016,32,6:6
16Composition optimized trimetallic PtNiRu dendritic nanostructures as I versatile and active electrocatalysts for alcohol oxidation显示文摘Platinum-based nano crystals are the most effective electrocatalysts for accelerati ng the chemical tran sformatio ns on the anode in direct alcohol fuel cells. To facilitate practical applications and overcome the drawbacks of diverse alcohols, it is significant to develop electrocatalysts with high activities and a wide fuel flexibility. Here, we demonstrate a practicable solution method for fabricating composition tun able trimetallic PtNiRu den dritic nano structures (DNSs) which can serve as versatile and active catalysts for electrooxidatio n of a variety of liquid alcohols. A series of trimetallic DNSs with tun able Pt/Ni/Ru atomic ratios were successfully syn thesized by simply adjusti ng the feeding of precursors. Detailed electrochemical test indicates that, among other compositions, the Pt66Ni27Ru7 DNSs present much superior electroactivity in catalyzing electrooxidation of liquid alcohols in acidic mediums. Specifically, the mass activity and specific activity on the Pt66Ni27Ru7 DNSs, for electrooxidation of methanol, ethanol, and ethylene glycol, are 4.57 and 4.34 times, 3.55 and 3.42 times, and 2.37 and 2.28 times that of the commercial Pt black, respectively. X-ray photoelectron spectroscopy and CO stripping studies reveal the adsorption of CO on these PtNiRu DNSs is much weaker than on pure Pt. Meanwhile, the surface Ru sites can provide neighbouring -OH groups to facilitate the oxidati on and removal of the adsorbed in termediates (-CO) on the surface Pt sites, effectively improvi ng the CO tolera nee of the catalysts. The PtNiRu DNSs also show effectively boosted capacity for breaking the C-C bond in C2-alcohols, showing great potential for fuel-flexible fuel cell applications.Yan Lu Wei Wang Xiaowei Chen Yuhui Zhang Yanchen Han Yong Cheng Xue-Jiao Chen Kai Liu Yuanyuan Wang Qiaobao Zhang Shuifen Xie 2019Nano Research2019,12,3:6
17Simpler criterion and flexibility of operation complexity for perfectly teleporting arbitrary n-qubit state with 2n-qubit pure state显示文摘A criterion for whether a pure-state quantum channel consisting of 2n qubits averagely distributed between two nodes can be used for perfectly teleporting an arbitrary n-qubit state via Bell-state measurements is educed.Specifically,a matrix is composed of the coefficients of the known channel state and whether the matrix is unitary decides the criterion.As the criterion is apparently different from the usual standard entanglement criterion (USEC),its applicability is enlarged and verified by other measuring bases.Thorough analyses have further simplified the resultant criterion,so that a much simpler criterion than the USEC is conclusively obtained.Moreover,the flexibility of operation complexity between the non-unitary measurements and the unitary reconstructions is explicitly exhibited.ZUO XueQin 1,LIU YiMin 2,ZHANG ZiYun 1,ZHANG Wen 1 & ZHANG ZhanJun 1 1 Key Laboratory of Optoelectronic Information Acquisition & Manipulation of Ministry of Education of China,School of Physics & Material Science,Anhui University,Hefei 230039,China 2 Department of Physics,Shaoguan University,Shaoguan 512005,China 2010Science China(Physics,Mechanics & Astronomy)2010,53,11:5
18Towards Flexible All-Carbon Electronics:Flexible Organic Field-Effect Transistors and Inverter Circuits Using Solution-Processed All-Graphene Source/Drain/Gate Electrodes显示文摘Flexible organic field-effect transistors(OFETs)using solution-processable functionalized graphene for all the electrodes(source,drain,and gate)have been fabricated for the first time.These OFETs show performance comparable to corresponding devices using Au electrodes as the source/drain electrodes on SiO2/Si substrates with Si as the gate electrode.Also,these devices demonstrate excellent flexibility without performance degradation over severe bending cycles.Furthermore,inverter circuits have been designed and fabricated using these all-graphene-electrode OFETs.Our results demonstrate that the long-sought dream for all-carbon and flexible electronics is now much closer to reality.Yongsheng Chen Yanfei Xu Kai Zhao Xiangjian Wan Jiachun Deng Weibo Yan 2010Nano Research2010,3,10:5
19Effect of Spanwise Flexibility on Propulsion Performance of a Flapping Hydrofoil at Low Reynolds Number显示文摘Spanwise flexibility is a key factor influencing propulsion performance of pectoral foils.Performances of bionic fish with oscillating pectoral foils can be enhanced by properly selecting the spanwise flexibility.The influence law of spanwise flexibility on thrust generation and propulsion efficiency of a rectangular hydro-foil is discussed.Series foils constructed by the two-component silicon rubber are developed.NACA0015 shape of chordwise cross-section is employed.The foils are strengthened by fin rays of different rigidity to realize variant spanwise rigidity and almost the same chordwise flexibility.Experiments on a towing platform developed are carried out at low Reynolds numbers of 10 000,15 000,and 20 000 and Strouhal numbers from 0.1 to 1.The following experimental results are achieved: (1) The average forward thrust increases with the St number increased;(2) Certain degree of spanwise flexibility is beneficial to the forward thrust generation,but the thrust gap is not large for the fins of different spanwise rigidity;(3) The fin of the maximal spanwise flexibility owns the highest propulsion efficiency;(4) Effect of the Reynolds number on the propulsion efficiency is significant.The experimental results can be utilized as a reference in deciding the spanwise flexibility of bionic pectoral fins in designing of robotic fish prototype propelled by flapping-wing.BI Shusheng CAI Yueri 2012Chinese Journal of Mechanical Engineering2012,25,1:5
20Practical high-performance lead-free piezoelectrics:structural flexibility beyond utilizing multiphase coexistence显示文摘Due to growing concern for the environment and human health, searching for high-performance lead-free piezoceramics has been a hot topic of scientific and industrial research. Despite the significant progress achieved toward enhancing piezoelectricity, further efforts should be devoted to the synergistic improvement of piezoelectricity and its thermal stability. This study provides new insight into these topics.A new KNN-based lead-free ceramic material is presented, which features a large piezoelectric coefficient(d33) exceeding 500 pC/N and a high Curie temperature(Tc) of ~200℃. The superior piezoelectric response strongly relies on the increased composition-induced structural flexibility due to lattice softening and decreased unit cell distortion. In contrast to piezoelectricity anomalies induced via polymorphic transition, this piezoelectricity enhancement is effective within a broad temperature range rather than a specific small range. In particular, a hierarchical domain architecture composed of nano-sized domains along the submicron domains was detected in this material system, which further contributes to the high piezoelectricity.Qing Liu Yichi Zhang Jing Gao Zhen Zhou Dong Yang Kai-Yang Lee Andrew Studer Manuel Hinterstein Ke Wang Xiaowen Zhang Longtu Li Jing-Feng Li 2020National Science Review2020,7,2:5
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