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On Fuzzy Preordered Structures and (Fuzzy) Hyperstructures

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1787-1798页

作者： Irina CRISTEA Morteza JAFARPOUR Seyed sh. MOUSAVI School of Applied Sciences University of Nova Gorica Department of Civil Engineering and Architecture University of Udine Mathematics Department Vali-e-Asr University of Rafsanjan Mathematics Department Shahid Bahonar University of Kerman

This article presents a connection between fuzzy preordered structures and hyperstructures. Firstly, we introduce the notion of fuzzy preordered semigroup and then, we construct a semihypergroup associated with it, giving some properties of the associated hyperstructure. Secondly, we define the notion of fuzzy preordered ring in order to construct a fuzzy hyperring.

关键词： Fuzzy preordered semigroup hypergroup fuzzy hyperring mutually associativity

Vertically Aligned Silicon Carbide Nanowires/Boron Nitride Cellulose Aerogel Networks Enhanced Thermal Conductivity and Electromagnetic Absorbing of Epoxy Composites

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Nano-Micro Letters 2022年第7期14卷 209-227页

作者： Duo Pan Gui Yang Hala MAbo-Dief Jingwen Dong Fengmei Su Chuntai Liu Yifan Li Ben Bin Xu vign.sh murugadoss Nithesh Naik Salah MEl-Bahy Zeinhom MEl-Bahy Minan Huang Zhanhu Guo Key Laboratory of Materials Processing and Mold(Zhengzhou University) Ministry of EducationNational Engineering Research Center for Advanced Polymer Processing TechnologyZhengzhou UniversityZhengzhou 450002People’s Republic of China Department of Chemistry College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Mechanical and Construction Engineering Faculty of Engineering and EnvironmentNorthumbria UniversityNewcastle upon Tyne NE18STUK Integrated Composites Laboratory(ICL) Department of Chemical and Biomolecular EngineeringUniversity of TennesseeKnoxvilleTN 37996USA Advanced Materials Division Engineered Multifunctional Composites(EMC)Nanotech LLCKnoxvilleTN 37934USA College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024People’s Republic of China Department of Mechanical and Manufacturing Engineering Manipal Institute of TechnologyManipal Academy of Higher EducationManipalKarnataka 576104India Department of Chemistry Turabah University CollegeTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Chemistry Al-Azhar UniversityNasr CityCairo 11884Egypt

With the innovation of microelectronics technology, the heat dissipation problem inside the device will face a severe test. In this work, cellulose aerogel(CA) with highly enhanced thermal conductivity(TC) in vertical planes was successfully obtained by constructing a vertically aligned silicon carbide nanowires(SiC NWs)/boron nitride(BN) network via the ice template-assisted strategy. The unique network structure of SiC NWs connected to BN ensures that the TC of the composite in the vertical direction reaches 2.21 W m^(-1) K^(-1) at a low hybrid filler loading of 16.69 wt%, which was increased by 890% compared to pure epoxy(EP). In addition, relying on unique porous network structure of CA, EP-based composite also showed higher TC than other comparative samples in the horizontal direction. Meanwhile, the composite exhibits good electrically insulating with a volume electrical resistivity about 2.35 × 10^(11) Ω cm and displays excellent electromagnetic wave absorption performance with a minimum reflection loss of-21.5 dB and a wide effective absorption bandwidth(<-10 dB) from 8.8 to 11.6 GHz. Therefore, this work provides a new strategy for manufacturing polymer-based composites with excellent multifunctional performances in microelectronic packaging applications.

关键词： Epoxy Ice template Vertical alignment Thermal conductivity Multifunctionality

Comparative studies on Y(Ⅲ)and Dy(Ⅲ)extraction from hydrochloric and nitric acids by Cyanex 572 as a novel extractant

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Journal of Rare Earths 2018年第12期36卷 1342-1350页

作者： N.E.El-Hefny M.S.Gasser sh.sh.Emam W.H.Mahmoud H.F.Aly Hot Laboratories Centre Atomic Energy Authority Faculty of Science Ain Shams University

Extraction of Y(III) and Dy(III) from hydrochloric and nitric acids by Cy-572 in kerosene was studied. The factors affecting the extraction were separately investigated. The stoichiometry of the extracted species was deduced on the basis of slope analysis method. Evaluation of extraction equilibrium and stripping investigation was studied as well as saponification effect of Cy-572. The composition of the extracted metal species in the organic phase was found to be [MA·(HA)] for Y(III) or Dy(III) in both media.1.0 mol/L HCI is the best stripping agent for each metal ion from the studied acidic media in one *** Cy-572 does not exhibit any selectivity towards the extraction of Y(III) or Dy(III) from both HCI and HNOsolutions. Based on the obtained results, the data were compared and the separation feasibility between lanthanides and Y(III) in the two media was discussed.

关键词： Extraction Cyanex-572 Yttrium Lanthanides Separation factor Saponification

Scale dependence of tensile strength of micromachined polysilicon MEMS structures due to microstructural and dimensional constraints

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Chinese Science Bulletin 2001年第16期46卷 1392-1397页

作者： Ding, JN Meng, YG Wen, sh Tsing Hua Univ Natl Tribol Lab Beijing 100084 Peoples R China

The success of microelectromechanical systems (MEMS) as a key technology in the 21st century depends in no small part on the solution of materials issues associated with the design and fabrication of complex MEMS devices. The reliable mechanical properties of these thin films are critical to the safety and functioning of these microdevices and should be accurately determined. In order to accomplish a reliable mechanical design of MEMS, a new microtensile test device using a magnetic-solenoid force actuator was developed to evaluate the mechanical properties of microfabricated polysilicon thin films with dimensions of 100—660 mm length, 20—200 mm width, and 2.4 mm thickness. It was found that the measured average value of Young抯 modulus, 164±1.2 GPa, falls within the theoretical bounds. The average fracture strength is 1.36 GPa with a standarddeviation of 0.14 GPa, and the Weibull modulus is 10.4—11.7, respectively. Statistical analysis of the specimen size effect on the tensile strength predicated the size effect on the length, the surface area and the volume of the specimens due tomicrostructural and dimensional constraints. The fracturestrength increases with the increase of the ratio of surfacearea to volume. In such cases the size effect can be tracedback to the ratio of surface area to volume as the governing parameter. The test data account for the uncertainties inmechanical properties and may be used in the future reliability design of polysilicon MEMS. The testing of 40specimens to failure results in a recommendation for design that the nominal strain be maintained below 0.0057.

关键词： microelectromechanical systems polysilicon elasticmodulus tensile strength size effect.

The Alexandria retinopathy of prematurity model(Alex-ROP): postnatal weight gain screening algorithm application in a developing country

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 296-301页

作者： Islam sh Ahmed Adham AO Badeeb Department of Ophthalmology Faculty of MedicineAlexandria Main University Hospital Department of Pediatrics and Neonatology Faculty of Medicine Alexandria University maternity Hospital

AIM: To suggest a novel retinopathy of prematurity(ROP) screening model in developing countries incorporating postnatal weight gain ratios(PWGR) to traditional parameters to maintain sensitivity and improve specificity in detecting ROP. METHODS: Analysis of weekly PWGR of infants from one tertiary referral center during six months to determine the age at which the PWGR with the highest predictability for ROP development which was referred to as the postnatal net weight gain ratio(NWGR). NWGR was added to conventional criteria to describe a new model(The Alex-ROP model). RESULTS: Of 560 infants were included. NWGR 28 d after birth was the most predictive factor for the development of ROP. A new model Alex-ROP recommending screening infants with gestational age(GA) ≤33 wk or birth weight ≤1500 g and NWGR at 28 d after birth <0.3 was suggested. A second screening model referred to as High-grade AlexROP(Hg Alex-ROP) model to detect worse grade ROP(Both type 1 and type 2) recommending a cutoff point of NWGR <0.15 between birth and 28^(th) day. CONCLUSION: Both Alex-ROP and Hg Alex-ROP models are easy to apply to improve the specificity of ROP screening in developing countries while maintaining high sensitivity.

关键词： screening retinopathy of prematurity postnatal weight gain

Experimental Study of Wave Pressure on a Breakwater Pier

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China Ocean Engineering 1999年第2期14卷 209-216页

作者： Pan, sh Xia, QY Lin, SQ Xu, LH Hohai Univ Coll Harbour Waterway & Coastal Engn Dept Coastal Engn Nanjing 210098 Peoples R China Fujian Prov Ports & shipping Adm Bur Fuzhou 350009 Peoples R China

Test studies on the wave pressure on a breakwater pier show that the influence of transmissive wave pressure on the outside wall of the breakwater pier is considerable, when the width of the pier is not very large. The variations of transmissive wave pressure on the breakwater pier with different widths are compared and the relationship is obtained between relative transmitting distance b/L and wave pressure reduction factor K, which may be used in the design of similar breakwater piers.

关键词： wave pressure breakwater pier

Staircase pulse voltammetry

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Chinese Journal of Chemistry 1995年第5期13卷 396-407页

作者： Mo, JY Chen, sh Zou, YD Cai, PX ZHONGshAN UNIV DEPT CHEMCANTON 510275GUANGDONGPEOPLES R CHINA

The faradaic current of interest can often be obscured by some extraneous current. A new method called staircase pulse voltammetry (SPV), with which involving a potential pulse is superimposed on a staircase, is used for removing the double-layer charging; current. This paper presents the theoretical consideration and the experimental evidence of this method for a simple reversible system and a catalytic process. The parameters affecting currents are also discussed. Experimental verifications are in agreement with the theories.

关键词： staircase pulse voltammetry simple reversible system catalytic process

Effect of the duty cycle of pulsed current on nanocomposite layers formed by pulsed electrodeposition

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Rare Metals 2010年第2期29卷 209-213页

作者： M.Aliofkhazraei sh.Ahangarani A.Sabour Rouhaghdam Department of Materials Engineering Faculty of Engineering Tarbiat Modares University Department of Advanced Materials & Renewable Energies Iranian Research Organization for Science and Technology(IROST)

Nickel-tungsten/carbon nanotube nanocomposite layers with high content and uniform dispersion of carbon nanotubes were fabricated using pulsed electrodeposition *** layers were analyzed by scanning electron microscopy, atomic force microscopy, microhardness, and Tafel polarization *** effect of the duty cycle of pulsed current or concentration of carbon nanotubes in the metallic matrix on electrochemical and mechanical properties of obtained layers has been *** has been shown that both the electrochemical and mechanical properties of nanocomposite layers that formed by pulsed current were improved significantly with respect to un-composed Ni-W *** results were not only concerned by the concentration of carbon nanotubes in the layer but also influenced by the distribution of nanoparticulates in the metallic matrix.

关键词： nanocomposite corrosion nanostructure carbon nanotubes

Monoenergetic electron parameters in a spheroid bubble model

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Chinese Physics B 2013年第2期22卷 347-351页

作者： H.Sattarian sh.Rahmatallahpur T.Tohidi Maraghe Branch Physics DepartmentIslamic Azad UniversityMaraghehIran Bonab Branch Physics DepartmentIslamic Azad UniversityBonabIran Department of Physics Azarbaijan University of Tarbiat MoallemTabrizIran

A reliable analytical expression for the potential of plasma waves with phase velocities near the speed of light is *** presented spheroid cavity model is more consistent than the previous spherical and ellipsoidal models and it explains the mono-energetic electron trajectory more accurately,especially at the relativistic *** maximum energy of electrons is calculated and it is shown that the maximum energy of the spheroid model is less than that of the spherical *** electron energy spectrum is also calculated and it is found that the energy distribution ratio of electrons △E/E for the spheroid model under the conditions reported here is half that of the spherical model and it is in good agreement with the experimental value in the same *** a result,the quasi-mono-energetic electron output beam interacting with the laser plasma can be more appropriately described with this model.

关键词： quasi-mono-energetic electron bunches intense laser plasma accelerator laser wake field bubble regime