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Improving the Economic Values of the recycled Plastics Using Nanotechnology Associated Studies

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Journal of Materials Science & Technology 2014年第9期30卷 854-859页

作者： W.S.Khan r.Asmatulu S.Davuluri V.K.Dandin Department of Mechanical Engineering Wichita State University 1845 FairmountWichita KS 67260-0133 USA

recycled polystyrene （PS） cups were chopped up and separately incorporated with multiwall carbon nanotubes （MWCNTs） and NiZn ferrite （Ni0.6Zn0.4Fe2O4） nanoparticles prior to electrospinning under different conditions. These nanoscale inclusions were initially dispersed well in dimethylformamide （DMF）, and then known amounts of the recycled PS pieces were added to the dispersions prior to 30 min of sonication followed by 4 h of high-speed agitation at 750 r/min. The thermal, dielectric, surface hydrophobic, and magnetic properties of the resultant nanocomposite fibers were determined by thermal comparative, capacitance bridge, vibrating sample magnetometer （VSM）, and goniometer techniques, respectively. Test results confirmed that the physical properties of recycled nanofibers were significantly increased as a function of the inclusion concentrations, which may be because of their excellent properties. The consumption of polymeric products as well as their waste materials has dramatically grown worldwide. Although plastic recycling, reprocessing, and reusing rates are growing, the physical properties and economic value of recycled plastics are significantly low. Consequently, this work provides a detailed explanation of how to improve recycled plastics, making them into highly valued new nanoproducts for various industrial applications, including filtration, textile, transportation, construction, and energy.

关键词： recycled polystyrene NiZn ferrite Multiwall carbon nanotubes (MWCNTs) Electrospinning Nanocomposite fibers Physical properties

Influence of the Ionosphere on the Observation of the Mid-Latitude Pi2 Pulsations at the Global Scale

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空间科学学报 2005年第5期25卷 447-449页

作者： r.A.rakhmatulin A.Y.Pashinin Institute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 RussiaInstitute of Solar-Terrestrial Physics Siberian Branch Russian Academy of Sciences Irkutsk 664033 Russia

results of our investigation showed that occurrence frequency of Pi2 over a 24 hour period undergoes seasonal variations in time coincidence with foF2. In the winter months, at sunrise and sunset (when foF2gradients are the largest) the observation probability of these oscillations is minimal. At periods of summer solstice when the F2-layer persists almost round the clock, no effect of Pi2 pulsation attenuation is observed at sunrise and sunset. The pulsation amplitudes behave in a similar manner. results of this study suggest the conclusion that the propagation of signal from the Pi2 sourse into the mid-latitudes, and also the parameters of these pulsations are essentially affected by electron density in the ionospheric F2-layer.

关键词： Pi2 电离层纬度电子总量地磁

role of Oct4 in the early embryo development

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Cell regeneration 2014年第1期3卷 50-59页

作者： Guangming Wu Hans r Schöler Max Planck Institute for Molecular Biomedicine Department of Cell and Developmental BiologyRöntgenstrasse 2048149 MünsterGermany University of Münster Medical FacultyDomagkstr.348149 MünsterGermany

Oct4 is a key component of the pluripotency regulatory network,and its reciprocal interaction with Cdx2 has been shown to be a determinant of either the self-renewal of embryonic stem cells(ESCs)or their differentiation into ***4 of maternal origin is postulated to play critical role in defining totipotency and inducing pluripotency during embryonic ***,the genetic elimination of maternal Oct4 using a Cre-lox approach in mouse revealed that the establishment of totipotency in maternal Oct4–depleted embryos was not affected,and that these embryos could complete full-term development without any obvious *** results indicate that Oct4 is not essential for the initiation of pluripotency,in contrast to its critical role in maintaining *** conclusion is further supported by the formation of Oct4-GFP–and Nanog-expressing inner cell masses(ICMs)in embryos with complete inactivation of both maternal and zygotic Oct4 expression and the reprogramming of fibroblasts into fully pluripotent cells by Oct4-deficient oocytes.

关键词： Oct4 Oct4B Totipotency Pluripotency Embryo Development

Antigen recognition in autoimmune diabetes:a novel pathway underlying disease initiation

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Precision Clinical Medicine 2018年第3期1卷 102-110页

作者： Xiaoxiao Wan Emil r.Unanue Department of Pathology and Immunology Washington University School of MedicineSt.LouisMO 63108USA

Development of human autoimmune disorders results from complex interplay among genetic,environmental,and immunological risk *** much heterogeneity in environmental triggers,the leading genes that give the propensity for tissue-specific autoimmune diseases,such as type 1 diabetes,are those associated with particular class II major histocompatibility complex *** genetic predisposition precipitates presentation of tissue antigens to MHC-II-restricted CD4 T *** properly activated,these self-reactive CD4 T cells migrate to the target tissue and trigger the initial immune *** the non-obese diabetic mouse model of spontaneous autoimmune diabetes,much insight has been gained in understanding how presentation of physiological levels of self-antigens translates into pathological *** this review,we summarize recent advances illustrating the features of the antigen presenting cells,the sites of the antigen recognition,and the nature of the consequent T cell *** emphasize emerging evidence that highlights the importance of systemic presentation of catabolized tissue antigens in mobilization of pathogenic T *** implication of these studies in therapeutic perspectives is also discussed.

关键词： autoimmune Antigen gained

MODELING OF 'BANDING' MICrOSTrUCTUrE FOrMATION IN CENTrIFUGALLY SOLIDIFIED Ti-6Al-4V ALLOY

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Acta Metallurgica Sinica(English Letters) 2008年第6期21卷 399-408页

作者： D.r. Liu E：J. Guo L.P. Wang School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150040 China Institute of Metal research Chinese Academy of Sciences Shenyang 110016 China

Numerical investigations of the ＇banding＇ microstructure formation during solidification of Ti-6Al-4 V alloy in the centrifugal casting are conducted using a multi-scale model, which combines the finite difference method （FDM） at the macroscale with a cellular automaton （CA） model at the microscale. The macro model is used to simulate the fluid flow and heat transfer throughout the casting. The micro model is used to predict the nucleation and growth of microstructures. With the proposed model, numerical simulations are performed to study the influences of the nucleation density, mould rotation speed, and casting size upon the ＇banding＇ microstructure formation. It is noted that changing the nucleation density has a minor effect on the microstructure formation. The rotation speed promotes the formation of ＇banding＇ microstructure, which is more noticeable for larger size castings. The ＇major mechanism responsible for this ＇banding＇ phenomenon is the spatial variation in cooling rates created by centrifugal force.

关键词： Modeling 'Banding' microstructure Ti-6Al-4V alloy Centrifugal casting

Uniform,Highly Conductive,and Patterned Transparent Films of a Percolating Silver Nanowire Network on rigid and Flexible Substrates Using a Dry Transfer Technique

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Nano research 2010年第8期3卷 564-573页

作者： Anuj r.Madaria Akshay Kumar Fumiaki N.Ishikawa Chongwu Zhou Department of Electrical Engineering and Center for Energy Nanoscience and Technology University of Southern CaliforniaLos AngelesCalifornia 90089USA

Silver nanowire films are promising alternatives to tin-doped indium oxide(ITO)films as transparent conductive *** this paper,we report the use of vacuum filtration and a polydimethylsiloxane(PDMS)-assisted transfer printing technique to fabricate silver nanowire films on both rigid and flexible substrates,bringing advantages such as the capability of patterned transfer,the best performance among various ITO alternatives(10Ω/sq at 85%transparency),and good adhesion to the underlying substrate,thus eliminating the previously reported adhesion *** addition,our method also allows the preparation of high quality patterned films of silver nanowires with different line widths and shapes in a matter of few minutes,making it a scalable ***,use of an anodized aluminum oxide(AAO)membrane in the transfer process allows annealing of nanowire films at moderately high temperature to obtain films with extremely high conductivity and good *** this transfer technique,we obtained silver nanowire films on a flexible polyethylene terephthalate(PET)substrate with a transparency of 85%,a sheet resistance of 10Ω/sq,with good mechanical *** analysis revealed that the Ag nanowire network exhibits two-dimensional percolation behavior with good agreement between experimentally observed and theoretically predicted values of critical volume。

关键词： Ag nanowire PDMS transfer transparent electrode flexible electronics percolation network

Flat Absorber Phosphorous Black Nickel Coatings for Space Applications

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Journal of Materials Science & Technology 2012年第2期28卷 118-124页

作者： V.Maria Shalini P.Arockiasamy r.Uma rani A.K.Sharma Thermal Systems Group ISRO Satellite CentreVimanapura PostBangalore-560 017India

A new process of flat absorber black nickel alloy coating tion from a bath containing nickel, zinc and ammonium was developed on stainless steel by electrodeposi- sulphates; thiocyanate and sodium hypophosphite for space applications. Coating process was optimized by investigating the effects of plating parameters, viz concentration of bath constituents, current density, temperature, pH and plating time on the optical properties of the black deposits. Energy dispersive X-ray spectroscopy showed the inclusion of about 6% phosphorous in the coating. The scanning electron microscopy studies revealed the amorphous nature of the coating. The corrosion resistance of the coatings was evaluated by the electrochemical impedance spectroscopy （EIS） and linear polarization （LP） techniques. The results revealed that, phosphorous addition confers better corro- sion resistance in comparison to conventional black nickel coatings. The black nickel coating obtained from hypophosphite bath provides high solar absorptance （αs） and infrared emittance （εIr） of the order of 0.93. Environmental stability to space applications was established by the humidity and thermal cycling tests.

关键词： Phosphorous black nickel alloy Electrochemical impedance spectroscopy Linear polarization Solar absorptance Infrared emittance

Hydromagnetic rotating flow of third grade fluid

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Applied Mathematics and Mechanics(English Edition) 2013年第12期34卷 1481-1494页

作者： T.HAYAT r.NAZ A.ALSAEDI M.M.rASHIDI Department of Mathematics Quaid-i-Azam University Department of Mathematics King Abdulaziz University Geni Mecanique Universite de Sherbrooke

This work investigates the flow of a third grade fluid in a rotating frame of reference. The fluid is incompressible and magnetohydrodynamic （MHD）. The flow is bounded between two porous plates, the lower of which is shrinking linearly. Mathematical modelling of the considered flow leads to a nonlinear problem. The solution of this nonlinear problem is computed by the homotopy analysis method （HAM）. Graphs are presented to demonstrate the effect of several emerging parameters, which clearly describe the flow characteristics.

关键词： third grade fluid shrinking sheet rotating frame magnetohydrodynamic(MHD) flow

Environmental screening and ligand-field effects to magnetism in CrI_(3) monolayer

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npj Computational Materials 2021年第1期7卷 1481-1490页

作者： D.Soriano A.N.rudenko M.I.Katsnelson M.rösner radboud University Institute for Molecules and MaterialsHeyendaalseweg 1356525 AJ NijmegenThe Netherlands Universitàdi Pisa Dipartimento di Ingegneria dell’InformazioneVia Caruso56122 PisaItaly Department of Theoretical Physics and Applied Mathematics Ural Federal University620002 EkaterinburgRussia

We study the microscopic origin of magnetism in suspended and dielectrically embedded CrI_(3)monolayer by down-folding minimal generalized Hubbard models from ab initio calculations using the constrained random phase *** models are capable of describing the formation of localized magnetic moments in CrI_(3)and of reproducing electronic properties of direct ab initio *** the magnet force theorem,we find a multi-orbital super-exchange mechanism as the origin of magnetism in CrI_(3)resulting from an interplay between ferro-and anti-ferromagnetic Cr-Cr d coupling channels,which is decisively affected by the ligand p *** show how environmental screening,such as resulting from encapsulation with hexagonal boron nitride,affects the Coulomb interaction in the film and how this controls its magnetic *** by a non-monotonic interplay between nearest and next-nearest neighbor exchange interactions we find the magnon dispersion and the Curie temperature to be non-trivially affected by the environmental screening.

关键词： properties monolayer exchange