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Solid Desiccant Dehumidification Techniques Inspired from Natural Electroosmosis Phenomena

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Journal of Bionic Engineering 2011年第1期8卷 90-97页

作者： B. Li y. y. yan Faculty of Engineering University of Nottingham Lenton Firs Building University Park Nottingham NG7 2RD UK

Electroosmosis has been shown to be an effective means of different applications in various fields such as Micro-Electro-Mechanical systems （MEMS） and biomimetics applications. This paper aims to prove the concept that the electroosmosis phenomena can also be cooperated into larger scale applications in the building service industry like dehumidification or damping proof. The electroosmotic flow inside a porous medium is validated experimentally to further understand the dehumidification mechanism of combined techniques. An experimental test validates that the condensation from the porous medium can be obtained by electroosmotic force generated by external electric field, especially for specific desiccant powders like zeolite and diatomaceous earth. With a range of volts from 5 V to 20 V applying between the testing plates, the maximum flow rate through the cross section in the testing plate achieved during the peak period is 1.35 laL＇min 1. These promising phenomena can act as an alternative way for energy choice in dehumidification industrial field. Further researches on new regeneration methods for solid desiccant dehumidification are required to make the system simple, energy-saving and suitable for small air conditioning units.

关键词： biomimetics electroosmotic flow solid desiccant dehumidification

Friction stir spot welding of SPCC low carbon steel plates at extremely low welding temperature

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Journal of Materials Science & Technology 2019年第5期35卷 733-741页

作者： y.F.Sun H.Fujii y.Sato y.Morisada Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki 567-004Japan School of Materials Science and Engineering Zhengzhou University Zhengzhou 450001 China

Friction stir spot welding (FSSW) was applied to 2.0 mm thick steel plate cold-rolled commercial (SPCC) low carbon steel plates at a very low rotation speed that ranged from 5 to 50rpm, which was much lower than that generally used for the conventional FSSW technique. Due to the very low heat input, the welding processes could therefore be completed at a peak welding temperature below 160℃. As a result, a significantly refined microstructure with an average grain size of about 0.41μm was formed in the stir zone of the joints and the JI {0-11 } and J2{1-1O} shear textures were the dominant components, which are different from the D1{11-2} and D2{-1-12} shear textures formed in the conventional FSSW joints. In addition, no heat affected zone could be detected along the crosssectional plane of the joints. Although a few void-like non-bonded areas were still observed along the interface between the upper and lower steel plates, the shear tensile loads of the joints increased to about 10.0 kN when welded at a condition of 8t, 20rpm and 30 s, and the joints fractured through the plug failure mode.

关键词： Friction stir spot welding Dynamic recrystallization Microstructure Steel

Active elastic metamaterials for subwavelength wave propagation control

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Acta Mechanica Sinica 2015年第3期31卷 349-363页

作者： y.y.Chen G.L.Huang Department of Mechanical and Aerospace Engineering University of Missouri

Recent research activities in elastic metamaterials demonstrate a significant potential for subwavelength wave propagation control owing to their interior locally resonant mechanism. The growing technological developments in electro/magnetomechanical couplings of smart materials have introduced a controlling degree of freedom for passive elastic metamaterials. Active elastic metamaterials could allow for a fine control of material physical behavior and thereby induce new functional properties that cannot be produced by passive approaches. In this paper, two types of active elastic metamaterials with shunted piezoelectric materials and electrorheological elastomers are proposed. Theoretical analyses and numerical validations of the active elastic metamaterials with detailed microstructures are pre- sented for designing adaptive applications in band gap structures and extraordinary waveguides. The active elastic metamaterial could provide a new design methodology for adaptive wave filters, high signal-to-noise sensors, and structural health monitoring applications.

关键词： Active elastic metamaterials Subwavelengthwave control Adaptive metastructures Smart materials

Assurance of the existence of a trans-boundary population of the snow leopard(Panthera uncia)at Tsagaanshuvuut-Tsagan-Shibetu SPA at the Mongolia-Russia border

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Integrative Zoology 2020年第3期15卷 224-231页

作者： Andrey D.POyARKOV Bariushaa MUNKHTSOG Miroslav P.KORABLEV Alexander N.KUKSIN Dmitry y.alexandrov Maria D.CHISTOPOLOVA Jose Antonio HERNANDEZ-BLANCO Оchirjav MUNKHTOGTOKH Alexander S.KARNAUKHOV Namdag LKHAMSUREN Munkhtsog BAyARAA Rodney M.JACKSON Aishwarya MAHESHWARI Viatcheslav V.ROZHNOV A.N.Severtsov Institute of Ecology and Evolution Russian Academy of Sciences Institute of General and Experimental Biology Mongolian Academy of SciencesMongolia State Biosphere Reserve Ubsunur KotlovinaRussia WWF Mongolia Mongolia WWF Russia Russia State Biosphere Reserve Uvs NuurMongolia Irbis Mongolian center Mongolia Wildlife Institute College of Nature Conservation of the Beijing Forestry UniversityBeijingChina Snow Leopard Conservancy USA Banda University of Agriculture and Technology BandaUttar PradeshIndia

The existence of a trans-boundary population of the snow leopard(Panthera uncia)that inhabits the massifs of Tsagaanshuvuut(Mongolia)-Tsagan-Shibetu(Russia)was determined through non-invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female *** genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 *** home range of a female snow leopard marked with a satellite Global Positioning System(GPS)collar was represented by the minimum convex polygon method(MCP)100,the MCP 95 method and the fixed kernel 95 *** results revealed insignificant genetic differentiation between snow leopards that inhabit both massifs(minimal fixation index[FST]),and the data testify to the unity of the cross-border ***,5 common individuals were identified from Mongolian and Russian *** finding clearly shows that their home range includes territories of both *** addition,regular movement of a collared snow leopard in Mongolia and Russia confirmed the existence of a cross-border snow leopard *** data support that trans-boundary conservation is important for snow leopards in both *** conclude that it is crucial for Russia to study the northern range of snow leopards in Asia.

关键词： FST home range Panthera uncia snow leopard trans-boundary population

Microstructure and mechanical properties of TiAl/TiAl joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

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Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： H.S.Ren y.L.Shang X.y.Ren y.J.Jing H.P.Xiong y.y.Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was *** filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni *** was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification *** results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on TiAl *** TiAl joint mainly consisted of β/B2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al *** diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and *** that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially *** micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 HV and 192 MPa,*** brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： TiAl Brazing Filler alloy Microstructure Mechanical properties

Reduction of structural response to near fault earthquakes by seismic isolation columns and variable friction dampers

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 113-122页

作者： y.Ribakov Department of Civil Engineering Ariel University Center of Samaria

This paper focuses on the investigation of a hybrid seismic isolation system with passive variable friction dampers for protection of structures against near fault earthquakes. The seismic isolation can be implemented by replacing the conventional columns fixed to the foundations by seismic isolating ones. These columns allow horizontal displacement between the superstructure and the foundations and decouple the building from the damaging earthquake motion. As a result, the forces in the structural elements decrease and damage that may be caused to the building by the earthquake significantly decreases. However, this positive effect is achieved on account of displacements occurring in the isolating columns. These displacements become very large when the structure is subjected to a strong earthquake. In this case, impact may occur between the parts of the isolating column yielding their damage or collapse. In order to limit the displacements in the isolating columns, it is proposed to add variable friction dampers. A method for selecting the dampers＇ properties is proposed. It is carried out using an artificial ground motion record and optimal active control algorithm. Numerical simulation of a sevenstory structure shows that the proposed method allows efficient reduction in structural response and limits the displacements at the seismic isolating columns.

关键词： seismic isolating columns variable friction dampers hybrid seismic isolation near fault earthquakes control algorithm

The first order phase-transition of polycrystal solid surfaces with nanothickness

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Rare Metals 2006年第6期25卷 709-714页

作者： y.A. Minaev Moscow State Steel & Alloys Institute and Russian Academy of Natural Science Leninsky prt.4 Moscow 119049 Russia

The fundamental equations of thermodynamics of a film have been used for describing a fundamental property of solid crystalline materials i.e. the first-order phase transition on the grain boundaries by the formation of two-dimensional liquid. The generalized equation that is obtained is used for calculating the premelting temperature of any metal, which has a value in the range of 0.55-0.86 of the melting point. The experimental diffusion coefficient of nitrogen in steel at premelting temperature is the same as in the liquid phase. The described phenomenon of phase transition on the grain boundaries decreases in case of radical modification of the existing process engineering of handling metals. It also provides a precise physical explanation to the super plasticity of fine-structure metal alloys.

关键词： thermodynamics of premelting nitrogen diffusion nitrided coatings structure high-temperature superplasticity

Modeling the interaction of nitrate anions with ozone and atmospheric moisture

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Chinese Physics B 2015年第10期24卷 160-165页

作者： A.y.Galashev Institute of High Temperature Electrochemistry Ural BranchRussian Academy of Sciences

The molecular dynamics method is used to investigate the interaction between one-six nitrate anions and water clusters absorbing six ozone molecules. The infrared（IR） absorption and reflection spectra are reshaped significantly, and new peaks appear at Raman spectra due to the addition of ozone and nitrate anions to the disperse water system. After ozone and nitrate anions are captured, the average（in frequency） IR reflection coefficient of the water disperse system increased drastically and the absorption coefficient fell.

关键词： nitrate ion ozone water cluster infrared and Raman spectra

FROM CRySTALLINE BLOCK SLIPS TO DOMINANCE OF NETWORK STRETCHING——MECHANISMS OF TENSILE DEFORMATION IN SEMI-CRySTALLINE POLyMERS

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Chinese Journal of Polymer Science 2002年第2期20卷 160-170页

作者： y. Men Univ Freiburg Fak Phys D-79104 Freiburg Germany

The mechanism of tensile deformation in semi-crystalline polymers was studied based on true stress-strain curvesobtained with the aid of a video-controlled tensile set-up. The deformation is affected by both the crystalline and theamorphous phases. However, the relative weights of the two portions change with the deformation stage. At lowdeformations the coupling and coarse slips of the crystalline blocks dominate the mechanical properties, which allows thesystem to maintain a homogeneous strain distribution in the sample. As the stretching increases, at a critical strain the forcegenerated from entangled fluid portions reaches a critical value to destroy the crystallites. The dominant deformationmechanism then changes into a disaggregation - recrystallization process.

关键词： Semi-crystalline polymer Deformation mechanism Network Mechanical property