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Carbon nanosheets derived from reconstructed lignin for potassium and sodium storage with low voltage hysteresis

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Nano Research 2021年第12期14卷 4664-4673页

作者： Keren Jiang Xuehai Tan Shengli Zhai ken Cadien Zhi Li Department of Chemical and Materials Engineering University of AlbertaEdmontonAlbertaT6G 1H9Canada

Lignin is the second most abundant and the only nature polymer rich in aromatic *** aromatic-unit-rich precursors often yield soft carbon after carbonization,the side chains in lignin crosslink with the aromatic units and form a rigid three-dimensional(3D)structure which eventually leads to hard *** a graphene oxide-catalyzed decomposition and repolymerization process,we successfully reconstructed lignin by partially tailoring the side *** to directly carbonized lignin,the carbonized reconstructed lignin possesses significantly fewer defects,86%fewer oxygen-functionalities,82%fewer micropores,and narrower interlayer *** parameters can be tuned by the amount of catalysts(graphene oxide).When tested as anode for K-ion and Na-ion batteries,the carbonized reconstructed lignin delivers notably higher capacity at low-potential range(especially for Na-storage),shows much-improved performance at high current density,and most importantly,reduces voltage hysteresis between discharge and charge process by more than 50%,which is critical to the energy efficiency of the energy storage *** study reveals that the voltage hysteresis in K-storage is much severer than that in Na-storage for all *** practical K-ion battery applications,the voltage hysteresis deserves more attention in future electrode materials design and the reconstruct ion strategy introduced in this work provides potential low-cost solution.

关键词： lignin batteries polarization voltage hysteresis ring-forming defects

Elastic line deformed on a pseudo-hypersurface by an external field in pseudo-Euclidean spaces

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Science China Mathematics 2008年第2期51卷 233-240页

作者： YCESAN Ahmet ken A.Ceylan Department of Mathematics Süleyman Demirel University32260 IspartaTurkey

We derive intrinsic formulation for elastic line deformed on a pseudo-hypersurface by an external field in the pseudo-Euclidean spaces E_v^*** formulation determines elastic line deformed on a pseudo-hypersurface.

关键词： elastic line pseudo-Euclidean spaces intrinsic formulation external field 53A35 53B30 74M30

Numerical and Experimental Studies of an Arc-heated Nonequilibrium Nozzle Flow

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Journal of Thermal Science 2003年第4期12卷 289-293页

作者： Michio Nishida ken-ichi Abe Hisashi Kihara Department of Aeronautics and Astronautics Kyushu University Fukuoka 812-8581 JapanDepartment of Aeronautics and Astronautics Kyushu University Fukuoka 812-8581 JapanDepartment of Aeronautics and Astronautics Kyushu University Fukuoka 812-8581 Japan

The arc-heated high-temperature gas is rotationally and vibrationally excited, and partially dissociated and ionized. When such gas flows inside a nozzle, energy transfers from rotational and vibrational energy modes to translational energy mode, and, in addition, recombination reactions occur. These processes are in thermal and chemical nonequilibrium. The present computations treat arc-heated nonequilibrium nozzle flows using a six temperature model (translational, rotational, N2 vibrational, O2 vibrational, NO vibrational and electron temperatures), and nonequilibrium chemical reactions of air. From the calculated flow properties, emission spectra at the nozzle exit were re-constructed by using the code for computing spectra of high temperature air. On the other hand, measurements of N2+(1-) emission spectra were conducted at the nozzle exit in the 20 kW arc-heated wind tunnel. Vibrational and rotational temperatures of N2 were determined using a curve fitting method on N2+(1-) emission spectra, with the vibrational and rotational temperatures for N2 and N2+ being assumed equal. Comparison of the measured and computed results elucidated that the experimental temperatures were larger than the computed ones. At present, we are trying to reveal the main reason for the discrepancy between the computed and measured N2 vibrational and rotational temperatures.

关键词： nozzle flow high temperature gas nonequilibrium flow arc-heated gas.

Use of self-organizing suppression and q-Gaussian mutation in artificial immune systems

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International Journal of Intelligent Computing and Cybernetics 2013年第3期6卷 296-322页

作者： Helder ken Shimo Renato Tinòs Department of Computing and Mathematics University of Sa˜o PauloSa˜o PauloBrazil

Purpose-The purpose of this paper is to propose two operators for diversity and mutation control in artificial immune systems(AISs).Design/methodology/approach-The proposed operators are applied in substitution to the suppression and mutation operators used in *** proposed mechanisms were tested in the opt-aiNet,a continuous optimization algorithm inspired in the theories of *** traditional opt-aiNet uses a suppression operator based on the immune network principles to remove similar cells and add random ones to control the diversity of the *** procedure is computationally expensive,as the Euclidean distances between every possible pair of candidate solutions must be *** work proposes a self-organizing suppression mechanism inspired by the self-organizing criticality(SOC)phenomenon,which is less dependent on parameter *** work also proposes the use of the q-Gaussian mutation,which allows controlling the form of the mutation distribution during the optimization *** algorithms were tested in a well-known benchmark for continuous optimization and in a bioinformatics problem:the rigid docking of ***-The proposed suppression operator presented some limitations in unimodal functions,but some interesting results were found in some highly multimodal *** proposed q-Gaussian mutation presented good performance in most of the test cases of the benchmark,and also in the docking ***/value-First,the self-organizing suppression operator was able to reduce the complexity of the suppression stage in the ***,the use of q-Gaussian mutation in AISs presented better compromise between exploitation and exploration of the search space and,as a consequence,a better performance when compared to the traditional Gaussian mutation.

关键词： Artificial immune system Evolutionary computation Self-adjusting systems

FOOD PRODUCTION ON A LIVING WALL:PILOT STUDY

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Journal of Green Building 2017年第3期12卷 23-38页

作者： Lara Nagle Stuart Echols ken Tamminga Department of Landscape Architecture The Pennsylvania State UniversityUniversity ParkPennsylvania 16802

Living walls and other vertical green infrastructure on building surfaces provide regulating,supporting,and cultural ecosystem services in the built *** walls can also generate food as a provisioning ecosystem *** article discusses a pilot study monitoring the productivity of a 7.5 m^(2) outdoor living wall system planted with produce crops during the 2015 summer growing season in State College,Pennsylvania,***,water usage,and soil moisture data were also collected to assess context and performance of the living wall system during the growing season.

关键词： living walls green walls urban agriculture ecosystem services Green Infrastructure(GI)

Recent advances towards aqueous hydrogen peroxide formation in a direct current plasma-liquid system

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High Voltage 2022年第3期7卷 405-419页

作者： Qiang Chen Junshuai Li Qiang Chen Kostya(ken)Ostrikov Shenzhen Research Institute of Xiamen University Institute of Electromagnetics and AcousticsFujian Provincial Key Laboratory of Plasma and Magnetic ResonanceKey Laboratory of Electromagnetic Wave Science and Detection TechnologyXiamen UniversityXiamenChina LONGi Institute of Future Technology and School of Materials&Energy Lanzhou UniversityLanzhouChina Laboratory of Plasma Physics and Materials Beijing Institute of Graphic CommunicationBeijingChina School of Chemistry and Physics and QUT Centre for Materials Science Queensland University of Technology(QUT)BrisbaneQueenslandAustralia

The aqueous phase hydrogen peroxide(H_(2)O_(2aq))produced from the plasma-liquid interactions can directly or synergistically(with other substances)affect the liquid chemistry,and therefore it is important to unfold the H_(2)O_(2aq)formation ***,up to now,a consensus on the H_(2)O_(2aq)formation mechanism is not *** review aims to survey the recent advances on the understanding of the H_(2)O_(2aq)formation mechanism in the system of a direct current discharge plasma operated over a liquid *** and experimental analyses indicate that the recombination of dissolved OH radicals(OHaq)is the dominant process for the H_(2)O_(2aq)formation,while the purported plasma-induced photolysis of water and the dissolution of gaseous H_(2)O_(2)are ruled out.

关键词： hydrogen liquid system

Fatigue analysis of piezoelectric microdevice based on a continuum damage model

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International Journal of Smart and Nano Materials 2013年第3期4卷 179-198页

作者： Xianqiao Wang ken P.Chong College of Engineering University of GeorgiaAthens 30606GAUSA Department of Mechanical and Aerospace Engineering George Washington UniversityWashington 20052DCUSA

The utilization of piezoelectric materials in MEMS devices under harsh environments has gained affordable appreciations due to its unique mechanical and electrical material ***,the reliability of MEMS devices triggered by fatigue damage remains elusive and needs to be further ***,we present a continuum constitutive model for piezoelectric materials containing a substantive amount of randomly dispersed *** constitutive equation of the piezoelectric materials with microcracks is formulated via Helmholtz free energy by combining the Kachanvo damage evolution law and the Chaboche fatigue damage development to express the fatigue damage growth.A case of the fatigue damage analysis of the piezoelectric microplate with transverse matrix cracks in the status of plane stress is presented by adopting the von Karman’s plate *** numerical schemes employed,the effect of cyclic impulsive loadings and electrical loadings on the fatigue damage and fatigue life prediction of a piezoelectric microplate is investigated and *** findings provide valuable insights into the fundamental mechanism of reliability in piezoelectric MEMS devices due to cyclic loadings,thereby offering new ways to exploit and fabricate the piezoelectric-based MEMS devices suitable for harsh conditions.

关键词： piezoelectric microplate constitutive equation fatigue analysis MEMS cyclic loading

High Strength Low Alloy (HSLA) Steels in Building Construction

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Journal of Iron and Steel Research International 2011年第S1期18卷 773-778页

作者： Sivakumaran ken Siva Jansto Steven G Department of Civil Engineering McMaster UniversityHamilton Reference Metals Company-CBMM 1000 Old Pond RoadBridgevillePA 15017USA

Majority of the buildings,including industrial buildings,are constructed using either structural steel (plates and structural shapes) or deformed bar steel reinforced *** buildings,however,must be designed to be safe and serviceable during construction and during use and *** objectives can be easily achieved by the use of steels having superior mechanical properties,ductility,weldability,fire resistance,*** the years,the steel industry has made improvements in steel making technologies resulting in high strength low alloy (HSLA) steels with superior steel properties well suited for building *** part of this paper presents the structural design considerations,and the constructional considerations associated with the building structures in general,and steel structures in *** second part of the paper looks at the acceptance criteria for HSLA steels for North American building codes and *** third part of the paper presents the structural properties of currently available HSLA steels for building *** discussion focuses on hot-rolled structural steel shapes as well as deformed steel bars for concrete *** paper argues that Niobium microalloying is the key to achieving superior properties in such steels.

关键词： HSLA steels building construction structural shapes deformed bars structural performance niobium

A gait generation and transition method for quadruped walking machine

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High Technology Letters 2011年第2期17卷 153-159页

作者：赵旦谱 Wu Dan Chen ken Department of Precision Instruments and Mechanology Tsinghua University Beijing 100084 P. R. China

In nature, quadrupeds as horses or cats change their gait to be suited to their motion speed. This fact is very important to realize smooth motion with different gaits. In this article a method of the gait transition for the quadruped walking machine is proposed. With analyzing the accustomed gaits of quadruped, some standard gaits and the relationships between duty factor and the phasic differences of the legs corresponding to the first leg could be concluded. With this, the gaits transferring could be continuous. Besides, celerity and on line method for generation and modifying gaits is studied, which can make the robot have a smooth motion to adapt the uncharted rough terrain.

关键词： gait generation transition quadruped robot