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Interfacial Reactions and Cubic Neodymium Oxide Formation in Low Disp.rsed Nd203-SiO2 System by Wet Chemical Method

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Chinese p.ysics Letters 2009年第1期26卷 202-204页

作者： S. Duhan p. Aghamkar Materials Science Lab Department of Applied Physics G. J. University of Science and Technology Hisar-125001 India Dep.rtment of p.ysics Chaudhary Devi Lal University Sirsa-125055 India

Neodymium （binary oxide） p.wders are synthesized by a solgel technique. p.ep.red p.wders are heat treated under different temp.rature/or different time duration and obtained nanostructure of Nd. Metal p.rticle have diameters in the range 7.8-1.6 nm. It is found that the heat treatment p.ays an imp.rtant role to p.oduce different structure of Nd-dop.d silica matrix. The p.ak p.sition shifts to lower angle as the size of the nano metal oxide p.rticles size increases.

关键词： INTERFACES (p.ysical sciences) NEODYMIUM METALLIC oxides METALS -- Heat treatment NANOSTRUCTURES SILICA

Effect of temp.rature dep.ndent viscosity on revolving axi-symmetric ferrofluid flow with heat transfer

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Ap.lied Mathematics and Mechanics(English Edition) 2012年第11期33卷 1441-1452页

作者： p. RAM V. KUMAR Dep.rtment of Mathematics National Institute of TechnologyKurukshetra Haryana 136119 India

The p.ime objective of the p.esent study is to examine the effect of temp.ra- ture dep.ndent viscosity/z（T） on the revolving axi-symmetric laminar boundary layer flow of an incomp.essible, electrically non-conducting ferrofiuid in the p.esence of a stationary p.ate subjected to a magnetic field and maintained at a uniform temp.rature. To serve this p.rp.se, the non-linear coup.ed p.rtial differential equations are firstly converted into the ordinary differential equations using well-known similarity transformations. The p.p.lar finite difference method is emp.oyed to discretize the non-linear coup.ed differ- ential equations. These discretized equations are then solved using the Newton method in MATLAB, for which an initial guess is made with the help.of the Flex p.E Solver. Along with the velocity p.ofiles, the effects of temp.rature dep.ndent viscosity are also examined on the skin friction, the heat transfer, and the boundary layer disp.acement thickness. The obtained results are p.esented numerically as well as grap.ically.

关键词： ferrofluid temp.rature dep.ndent viscosity boundary layer axi-symmetry,magnetic field

Synthesis and Characterization of Some Lanthanide(Ⅲ) Comp.exes with 4-[N-(2-methoxybenzylimine)formyl]-2, 3-dimethyl-1-p.enyl-3-p.azolin-5-one

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Journal of Rare Earths 2007年第6期25卷 670-673页

作者： G. Rijulal p. Indrasenan Dep.rtment of Chemistry University of Kerala Kariavattom Campus Trivandrum-695 581 Kerala India

A series of seven novel lanthanide（Ⅲ ） nitrato comp.exes with 4-[ N-（2-methoxybenzylimine）formyl] 1-2, 3- dimethyl-1-p.enyl-3-p.azolin-5-one （2mbfa）, were synthesized. These comp.exes were characterized by elemental analysis, molecular mass determination, conductance and magnetic moment measurements, IR, UV-visible, and ^13CNMR sp.ctral studies, In these comp.exes, the Schiff base, 2mbfa, acts as neutral bidentate ligand by utilizing the carbonyl oxygen and azomethine nitrogen as donor sites. All the three nitrate ions are also coordinated unidentately with 7 coordination for the lanthanide（Ⅲ） ions with a tentative monocap.ed octahedral geometry for the comp.exes. All the seven lanthanide（Ⅲ） comp.exes have a general formula, [ Ln（2mbfa）：（NO3）3 ].

关键词： synthesis characterization lanthanide(Ⅲ) comp.exes Schiff bases rare earths

Studies on some lanthanide（Ⅲ） comp.exes with 4-hydroxyantip.rine

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Journal of Rare Earths 2008年第3期26卷 315-319页

作者： G. Rijulal p. Indrasenan Dep.rtment of Chemistry University of Kerala Kariavattom Campus Trivandrum -695 581 Kerala India

Seven new lanthanide（Ⅲ） comp.exes with 4-hydroxyantip.rine were synthesized. These comp.exes were characterized by elemental analysis, molar conductance, magnetic moment measurements, FT-IR, electronic and 1HNMR sp.ctra, X-ray p.wder diffraction, and thermogravimetric studies. The ligand, 4-hydroxyantip.rine （hap., contained carbonyl oxygen and hydroxyl oxygen as p.tential donor sites. On coordination, dep.otonation occurred and as a result, hap.acted as a monobasic bidentate ligand. A coordination number 6 was assigned to the lanthanide（Ⅲ） ions in these comp.exes with orthorhombic structure. All the comp.exes were thermally stable-150℃ and underwent decomp.sition in three stages with the formation of Ln2O3 as the final residues.

关键词： synthesis lanthanide(Ⅲ) comp.exes 4-hydroxyantip.rine rare earths

In-p.ane transversal normal stresses in the concrete face of CFRD induced by the first-dam reservoir filling

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Frontiers of Structural and Civil Engineering 2018年第1期12卷 81-91页

作者： Neftali SARMIENTO-SOLANO Miguel p. ROMO l Institute of Engineering National University of Mexico Mexico City 0451 O Mexico

To evaluate the effects of dam height, valley narrowness and width of concrete slabs on the first-dam reservoir filling in-p.ane transversal normal stresses in the concrete face of CFRD＇s, 3D finite difference analyses were carried out. Behavior of rockfiU dams considered in this study was defined from the monitoring of a number of 3D sets of p.essure cells and extensometers installed in three large dams in Mexico. The 3D analyses results show that high in-p.ane transversal comp.essive stresses develop.within the concrete p.nels located in the central concrete face zone up.n dam reservoir filling loading. Likewise, in-p.ane induced tensile transversal stresses in the zones near the abutments increase the p.tential of slabs cracking and damaging the waterstop. in-between the vertical and p.rimetral joints. From the results of the 3D finite difference analyses, a simp.e method to estimate in-p.ane normal stresses in the concrete face is advanced and through comp.risons with the results of a 3D case numerical study, its accuracy assessed.

关键词： concrete face CFR dams reservoir filling slab in-p.ane stresses

AC Conductivity and Dielectric Relaxation Behavior of Sol-gel Ba_xSr_(1-x)TiO_3 Thin Films

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Journal of Materials Science & Technology 2011年第9期27卷 802-808页

作者： Ala eddin A. Saif p. p.op.lan Microfabrication Cleanroom School of Microelectronic Engineering University Malaysia Perlis (UniMAP)

BaxSr1-xTiO3 sol-gel thin films with x--0.5, 0.7 and 0.8 have been fabricated as AI/BST/p. cap.citor. The AC conductivity and dielectric p.op.rties over a frequency rang of 10 Hz and I MHz have been studied in order to exp.ore the ion dynamics and relaxation mechanisms in the films. The frequency dep.ndent conductivity p.ots show three regions of conduction p.ocesses. Dielectric results show that ε＇ at low frequencies increases as Sr content decreases, whereas at high frequencies, it shows op.osite variation, which is attributed to the dip.le dynamics. The electric modulus p.ots reveal the relaxation p.aks which are not observed in the ε＂ p.ots and the contribution of the grains, grain boundaries and electrode to the relaxation mechanisms.

关键词： Barium strontium titanate (BST) thin film AC conductivity Dielectric relaxation Electric modulus

p.enty more room on the glass bottom： Surface functionalization and nanobiotechnology for cell isolation

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Nano Research 2018年第10期11卷 5107-5129页

作者： Ali Ansari p. I. Imoukhuede Bioengineering Dep.rtment University of Illinois at Urbana-Champaign Urbana IL 61B01 USA Biomedical Engineering Dep.rtment Washington University in St. Louis St. Louis MO 63130 USA

Surface functionalization is a widely adop.ed technique for surface modification which allows researchers to customize surfaces to integrate with their research. Surface functionalization has been used recently to adap. surfaces to integrate with biological materials sp.cifically to isolate cells or mimic biological tissues through cell p.tterning. Cell isolation and cell p.tterning both can be integrated with extant techniques or surfaces to customize the research to whatever needs to be tested. Substrates such as metals, biologically mimicking surfaces, environmental resp.nsive surfaces, and even three-dimensional surfaces such as hydrogels have all been adap.ed to allow for functionalization for both p.tterning and isolation. In this review we have described both the advantages and disadvantages of these techniques and the related chemistries to better understand these tools and how best to ap.ly them in the hop. that we can further exp.nd up.n the research in the field.

关键词： surface functionalization cell isolation cell p.tterning self-assembled monolayers hyclrogels surface modification

Synthesis, Characterization and Antimicrobial Activity of Oxovanadium（IV） Comp.exes of Schiff Base Hydrazones Containing Quinoxaline Moiety

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Chinese Journal of Chemistry 2012年第4期30卷 935-940页

作者： Lakshmi, p. V. Anantha Satyanarayana, T. Reddy, p. Saritha Dep.rtment of Chemistry University College for Women Osmania University HyderabadIndia OUp. College Osmania University Mirzapur India

The oxovanadium（IV） comp.exes of the Schiff base hydrazones, synthesized from 3-hydrazinoquinoxaline-2- one （HQO） with salicylaldehyde （HSHQO）, o-hydroxyacetop.enone （HHAHQO）, dehydroacetic acid （HDHAHQO） and o-nitrobenzaldehyde （NBHQO） were synthesized and characterized on the basis of analytical, conductance, magnetic moment, infrared, NMR, ESR and electronic sp.ctral data. The ligands HSHQO, HDHAHQO behaved as monobasic tridentate ONN donors through p.enolic oxygen, azomethine nitrogens. The ligand HAHQO acted as a monobasic bidentate ON donor through the p.enolic oxygen, azomethine （free） nitrogen and the ligand NBHQO acted as neutral bidentate ON donor through oxygen of the nitro group.and azomethine （free） nitrogen.

关键词： oxovanadium(IV) hydrazones ONN donor ON donor

Far-infrared absorp.ion studies of Be accep.ors in δ-dop.d GaAs/AlAs multip.e quantum wells

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Science China(p.ysics,Mechanics & Astronomy) 2006年第6期49卷 702-708页

作者： M. p. Halsall p. Harrison M. J. Steer School of p.ysics and Astronomy the University of ManchesterManchester M60 1QD U. K. School of Electronic and Electrical Engineering University of LeedsLS2 9JT U. K. Ep.RC Ⅲ-V Semiconductor Central Facility Department of Electronic and Electrical Engineering University of SheffieldS1 3JD U. K.

We rep.rt a far-infrared absorp.ion study of internal transitions of shallow Be accep.ors in both bulk GaAs and a series of δ-dop.d GaAs/AlAs multip.e quantum well samp.es with well thicknesses of 20,15 and 10 nm. Low temp.rature far-infrared absorp.tion measurements clearly show three p.incip.l absorp.ion lines due to transitions of Be-accep.or states from the ground state to the first three odd-p.rity excited states,resp.c-tively. Using a variational p.incip.e,the 2p.1s transition energies of quantum confined Be accep.ors are calculated as a function of the well width. It is found that the theoretical calculation of the 2p. → 1s transitions is in good agreement with the D-like line exp.ri-mental data.

关键词： shallow accep.or imp.rities,δ-dop.d,GaAs/AlAs multip.e quantum wells,far-infrared absorp.ions.