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Control of light scattering by nanoparticles with optically-induced magnetic responses

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Chinese Physics B 2014年第4期23卷 41-51页

作者：刘伟 Andrey e. Miroshnichenko Yuri s. Kivshar College of Optoelectronic science and engineering National University of Defence Technology Nonlinear Physics Center and Center for Ultrahigh-bandwidth Devices for Optical systems CUDOs) Research School of Physics and EngineeringAustralian National University

Conventional approaches to control and shape the scattering pattems of light generated by different nanostructures are mostly based on engineering of their electric response due to the fact that most metallic nanostructures support only electric resonances in the optical frequency range. Recently, fuelled by the fast development in the fields of metamaterials and plasmonics, artificial optically-induced magnetic responses have been demonstrated for various nanostructures. This kind of response can be employed to provide an extra degree of freedom for the efficient control and shaping of the scattering patterns of nanoparticles and nanoantennas. Here we review the recent progress in this research direction of nanoparticle scattering shaping and control through the interference of both electric and optically-induced magnetic responses. We discuss the magnetic resonances supported by various structures in different spectral regimes, and then summarize the original results on the scattering shaping involving both electric and magnetic responses, based on the interference of both spectrally separated （with different resonant wavelengths） and overlapped dipoles （with the same resonant wavelength）, and also other higher-order modes. Finally, we discuss the scattering control utilizing Fano resonances associated with the magnetic responses.

关键词： optically-induced magnetic response scattering control Mie resonance Fano resonance

Pore structure of cementitious material enhanced by graphitic nanomaterial： a critical review

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Frontiers of structural and Civil engineering 2018年第1期12卷 137-147页

作者： s.A. GHAHARI e. GHAFARI L. AssI Department of Civil engineering Purdue University USA Department of Civil and environmental engineering University of South Carolina USA

Carbon nano tubes （CNT） has been introduced as an efficient nanomaterial in order to improve the mechanical and durability properties of concrete. The effect of CNT on the microstructures of cementitious materials has been widely reported. This paper combines a critical review on the effect of CNT on the pore and microstructure of cement composite with a discussion on the porosity measurement of pastes containing CNT using mercury intrusion porosimetry techniques （MIP）. It was found that, surface treatment by H2sO4 and HNO3 solution forms carboxyl acid groups on CNTs＇ surfaces that lead to the improvement of reinforcement. In this scope, this review paper involves analyzing the effect of CNT on the microstructure and the pore structure of cementitious materials. The existing methods of measuring the porosity of cementitious material are reviewed, in particular, the contact angle measurement is discussed in detail in which the most effective parameters and possible errors of calculation is presented.

关键词： carbon nano tubes microstructure porosity mercury intrusion porosimetry cement composite

Hierarchical closed form solutions for plates bent by localized transverse loadings

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Journal of Zhejiang University-science A(Applied Physics & engineering) 2007年第7期8卷 1026-1037页

作者： CARReRA e. GIUNTA G. BRIsCHeTTO s. Aeronautical and space Department Politecnico di Torino c.so Duca degli Abruzzi 24 10129 Torino Italy

3D and 2D closed form plate models are here applied to static analysis of simply supported square isotropic plates. 2D theories are hierarchically classified on the basis of the accuracy of the displacements and stresses obtained by comparison to the 3D exact results that could be assumed by the reader as benchmark for further analyses. Attention is mainly paid on localized loading conditions, that is, piecewise constant load. Also bi-sinusoidal and uniformly distributed loadings are taken into account. All of those configurations are considered in order to investigate the behavior of the 2D models in the case of continu- ous/uncontinuous, centric or off-centric loading conditions. The ratio between the side length a and the plate thickness h has been assumed as analysis parameter. Higher order 2D models yield accurate results for any considered load condition in the case of moderately thick plates, a/h=10. In the case of thick plates, a/h=5, and continuous/uncontinuous centric loading conditions high accuracy is also obtained. For the considered off-centric load condition and thick plates good results are provided for some output quantities. A better solution could be achieved by simply increasing the polynomial approximation order of the axiomatic 2D displacement field.

关键词： exact 3D model Hierarchical 2D models Principle of Virtual Displacements (PVD) Localized loading simply supported square isotropic plate

Increasing chloride concentration causes retention of mercury in melted Arctic snow due to changes in photoreduction kinetics

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Journal of environmental sciences 2018年第6期30卷 122-129页

作者： e.A.Mann s.e.Ziegler A.steffen N.J.O'Driscoll Department of environmental science Acadia University environmental science Programme Memorial University of Newfoundland environment and Climate Change Canada Science and Technology Branch Air Quality Research Division

Mercury（Hg） in the Arctic is a significant concern due to its bioaccumulative and neurotoxic properties, and the sensitivity of Arctic environments. Previous research has found high levels of Hg in snowpacks with high chloride（Cl-） concentrations. We hypothesised that Cl- would increase Hg retention by decreasing Hg photoreduction to Hg（0） in melted Arctic snow. To test this, changes in Hg photoreduction kinetics in melted Alert, NU snow were quantified with changing Cl- concentration and UV intensity. snow was collected and melted in Teflon bottles in May 2014, spiked with 0–10 μg/g Cl-, and irradiated with 3.52–5.78 W·m-2 UV（280–400 nm）radiation in a Luz Chem photoreactor. Photoreduction rate constants（k）（0.14–0.59 hr-1） had positive linear relationships with [Cl-], while photoreduced Hg amounts（Hg（Ⅱ）red） had negative linear relationships with [Cl-]（1287–64 pg in 200 g melted snow）. Varying UV and[Cl-] both altered Hg（Ⅱ）red amounts, with more efficient Hg stabilisation by Cl- at higher UV intensity, while k can be predicted by Cl- concentration and/or UV intensity, depending on experimental parameters. Overall, with future projections for greater snowpack Cl- loading,our experimental results suggest that more Hg could be delivered to Arctic aquatic ecosystems by melted snow（smaller Hg（Ⅱ）red expected）, but the Hg in the melted snow that is photoreduced may do so more quickly（larger k expected）.

关键词： Mercury Photoreduction Arctic Melted snow

Outcomes and management of viral hepatitis and human immunodeficiency virus co-infection in liver transplantation

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World Journal of Gastroenterology 2014年第2期20卷 414-424页

作者： stephen e Congly Karen e Doucette Carla s Coffin Liver Unit Division of Gastroenterology and HepatologyUniversity of CalgaryCalgaryAB T2N 4Z6Canada Division of Infectious Diseases University of AlbertaEdmontonAB T6G 2R3Canada

Liver transplantation for human immunodeficiency virus(HIV)positive patients with viral hepatitis co-infection is increasingly offered in many North American and european liver transplant *** studies have demonstrated acceptable post-transplant outcomes and no increased risk of HIV complications in patients coinfected with hepatitis B virus(HBV).However,liver transplantation in HIV positive patients with hepatitis C virus(HCV)has poorer outcomes overall,requiring careful selection of *** review aims to summarize the published literature on outcomes after transplant in HIV patients with HBV or HCV related end-stage liver disease and recommendations for *** particular the pre-transplant factors impacting outcomes in HCV/HIV co-infected candidates and importance of multidisciplinary management will be discussed.

关键词： Hepatitis B virus Human immunodeficiency virus co-infection Hepatitis C virus Co-infection Liver transplantation

Adsorption and photo-catalytic properties of layered lepidocrocite-like quasi-amorphous compounds based on modified potassium polytitanates

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Particuology 2014年第6期12卷 22-28页

作者： e.V.Tretyachenko A.V.Gorokhovsky G.Y.Yurkov F.s.Fedorov M.A.Vikulova D.s.Kovaleva e.e.Orozaliev Department of Chemistry Saratov State Technical University

TiO2 compounds possess relatively high adsorption abilities and exhibit high photocatalytic activities that exhibit potential for the destruction of organic pollutants in natural and waste *** potassium polytitanates modified using transition metals and their oxides/hydroxides generate new nanomaterials that operate in the visible spectral *** study presents the synthesis and investigation of the structure,composition and photocatalytic activity of powdered nanoscale quasi-amorphous potassium polytitanates particles modified with iron,zinc,copper,cobalt and nickel sulfate in aqueous *** of the powders investigated in this work exhibit a high adsorption capacity for methylene blue dye（15-20mg/g） related to the welldeveloped surface of the layered potassium polytitanate *** transition metals and their oxides/hydroxides influences the electronic structure of the obtained systems.A high photocatalytic activity was observed for systems containing iron,zinc,nickel and their oxides/hydroxides in the ultraviolet and visible ranges.

关键词： Layered potassium titanate Chemical modification Heterostructured particles Photocatalytic activity Adsorption

separation of ^(152+154)eu,^(90)sr from radioactive waste effluent using liquid–liquid extraction by polyglycerol phthalate

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Nuclear science and Techniques 2018年第6期29卷 76-84页

作者： M.F.Attallah s.e.Rizk s.A.shady Analytical Chemistry and Control Department Hot Laboratories Center Atomic Energy Authority of Egypt Chemistry of Nuclear Fuel Department Hot Laboratories Center Atomic Energy Authority of Egypt Technology of Nuclear Fuel Department Hot Laboratories Center Atomic Energy Authority of Egypt

A new polyglycerol phthalate extractant was prepared and characterized using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance(~1H NMR) spectroscopy, and thermogravimetric analysis. A preliminary study of the extraction of long-lived(^(90) sr and ^(152+154)eu) and short-lived(^(90) Y) radionuclides by polyglycerol phthalate was performed. The influence of different diluents, concentration of the acid, type of acid, and various interfering ions was explored. The stripping of ^(152+154)eu radionuclide was studied by using different acid solutions, and it was found that sulfuric acid was the ideal acid for this purpose. Furthermore,^(152+154)eu was extracted from the fission products(^(90) sr) and the extraction% of^(90) sr was found to improve in the presence of interfering ions.

关键词：放射性核种抽取液体 Fourier 分离浪费光谱学 NMR

emission colour tuning in KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)phosphor

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Journal of Rare earths 2024年第1期42卷 57-65,I0002页

作者： Janani K Gayathri e Vijayatha V Ramasubramanian s Thiyagarajan P Department of science and Humanities Nehru Institute of TechnologyKaliapuramThirumalayampalayamCoimbatoreIndia Department of sciences Amrita School of Physical SciencesAmrita Vishwa VidyapeethamCoimbatoreIndia Department of Physics Anna UniversityChennaiIndia

KLnF_(4):Yb^(3+),er^(3+)/Ho^(3+)(Ln=Y,Yb,Gd)phosphors were prepared by solid-state reaction *** each of the Yb^(3+)/er^(3+)and Yb^(3+)/Ho^(3+)co-doped phosphors independently,phase confirmation and morphological examination were accomplished using the X-ray diffraction technique and scanning electron microscope analysis.X-ray photoelectron spectroscopy analysis shows the charge state and existence of lanthanides and *** luminescence emissions of green and red colour were detected for the synthesized *** changes in the upconverted emission intensities and colour output pertaining to the change of the lanthanide host matrix along with dopants were investigated for the prepared *** the upconversion luminescence,erbium-doped samples exhibit a predominance of red emission while holmium-doped samples display a prevalence of green *** rare-earth er/Ho doped KYbF4shows strong red emission compared to other ***_(4):Yb,er/Ho exhibits relatively significant green upconve rsion emissions,while Yb,er-doped KGdF_(4)host displays a 10-fold increase in green/red emission ratio with an increase in the input power of 20-780 *** photoluminescence studies and decay curve analysis were carried out using UV light excitation for the developed phosphors.A higher lifetime of 2.2 ms was measured for the downshifting red emission in the Ho doped KYbF_(4)*** study suggests a potential for colour tunability in the upconversion and downshifting emissions through host modifications to the fluoride phosphor.

关键词： Rare earths energy transfer upconversion Downshifting Colour coordinates

evaluation of the seismic behavior of reinforced concrete structures with flat slab-column gravity frame and shear walls through nonlinear analysis methods

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earthquake engineering and engineering Vibration 2024年第3期23卷 713-726页

作者： M.A.Najafgholipour s.Heidarian Radbakhsh e.erfani Department of Civil and environmental engineering Shiraz University of TechnologyShiraz ***Iran Department of Building Civiland Environmental EngineeringConcordia UniversityMontréal H3G 1M8Canada

This paper presents an investigation of the seismic behavior of reinforced concrete(RC)structures in which shear walls are the main lateral load-resisting elements and the participation of flat slab floor systems is not considered in the seismic design *** this regard,the behavior of six prototype structures(with different heights and plan layouts)is investigated through nonlinear static and time history analyses,implemented in the Opensees *** results of the analyses are presented in terms of the behavior of the slab-column connections and their mode of failure at different loading ***,the global response of the buildings is discussed in terms of some parameters,such as lateral overstrength due to the gravity flat slab-column *** to the nonlinear static analyses,in structures in which the slab-column connections were designed only for gravity loads,the slab-column connections exhibited a punching mode of failure even in the early stages of ***,the punching failure was eliminated in structures in which a minimum transverse reinforcement recommended in ACI 318(2019)was provided in the slabs at joint ***,despite neglecting the contribution of gravity flat slab-column frames in the lateral load resistance of the structures,a relatively significant overstrength was imposed on the structures by the gravity frames.

关键词： RC flat slab-column frames seismic behavior nonlinear analysis time history analysis