bluuebunny/crossref_metadata_2025 huggingface dataset:
Divalent metals can reside on bonds in fullerenes
Authors: Gao Xuejiao , Sun Baoyun , Zhao Yuliang , Chen Bo-Zhen , Gao Xingfa
Published: April 2015

Inside C60, divalent metals prefer to reside on 6/6 bonds whereas trivalent metals prefer to sit above hexagonal rings.
Molecular dynamics simulation of the cooperative effect by different force fields in monosodium glutamate aqueous solution
Authors: Liu Fenghai , Wang Feng , Jia Guozhu , Huang Kama
Published: April 2015

Different force fields (GROMOS and OPLS) in conjunction with different water (SPC, SPCE, TIP3P, TIP4P and TIP5P) were assessed using molecular dynamics simulations of monosodium glutamate (MSG) aqueous solution.
Highly efficient electromagnetic interference shielding using graphite nanoplatelet/poly(3,4-ethylenedioxythiophene)–poly(styrenesulfonate) composites with enhanced thermal conductivity
Authors: Agnihotri Nidhi , Chakrabarti Kuntal , De Amitabha
Published: April 2015

We address the ongoing quest for high efficiency, lightweight and thermally conducting electromagnetic interference shields. GNP/PEDOT:PSS composites are used to achieve an extremely high shielding effectiveness with enhanced thermal conductivity.
A simple assay for glutathione in whole blood
Authors: Hakuna Lovemore , Doughan Brandon , Escobedo Jorge O. , Strongin Robert M.
Published: April 2015

A simple dried blood spot isolation protocol yields glutathione samples that are free from optical interferents. Fluorescence detection and quantitation is achieved using a fast response probe selective for glutathione.
Pharmacological and therapeutic properties of new derivatives of renin inhibitors and endothelin receptor antagonists, and the methods of their determination
Authors: Stolarczyk Mariusz , Apola Anna , Maślanka Anna , Krzek Jan
Published: April 2015

We review analytical methods used to determine new substances with hypotensive activity from two pharmacological groups: renin inhibitors and endothelin receptor antagonists.
Iron-catalyzed aerobic C–H functionalization of pyrrolones
Authors: Liu Li-wei , Wang Zhen-zhen , Zhang Hui-hui , Wang Wan-shu , Zhang Ji-zong , Tang Yu
Published: April 2015

The aerobic oxidation of pyrrolones catalyzed by Fe(OTf)3to form reactiveN-acyliminium ion intermediates that undergo nucleophilic additions to give the corresponding products is described.
Photoreactivity of the linker region of two consecutive G-quadruplexes formed by human telomeric DNA
Authors: Li Yue , Sugiyama Hiroshi
Published: April 2015

The photoreaction method was applied to probe the linker region of two consecutive G-quadruplexes.
Construction of unique six-coordinated titanium species with an organic amine ligand in titanosilicate and their unprecedented high efficiency for alkene epoxidation
Authors: Xu Le , Huang Da-Ding , Li Chen-Geng , Ji Xinyi , Jin Shaoqing , Feng Zhaochi , Xia Fei , Li Xiaohong , Fan Fengtao , Li Can , Wu Peng
Published: April 2015

An organic–inorganic titanosilicate with an amine ligand shows high catalytic activity, selectivity and recyclability in alkene epoxidation.
A novel, colorimetric method for biogenic amine detection based on arylalkylamine N-acetyltransferase
Authors: Leng Pei-Qiang , Zhao Feng-Lan , Yin Bin-Cheng , Ye Bang-Ce
Published: April 2015

We developed a novel colorimetric method for rapid detection of biogenic amines based on arylalkylamine N-acetyltransferase (aaNAT).
Robust SiO2-modified CoFe2O4 hollow nanofibers with flexible room temperature magnetic performance
Authors: Jing Panpan , Pan Lining , Du Jinlu , Wang Jianbo , Liu Qingfang
Published: April 2015

Flexible room temperature magnetic parameters (Ms and Hc) of electrospun SiO2-modified CoFe2O4 hollow nanofibers annealed at 1000 °C.
Tuning the switching behavior of binary oxide-based resistive memory devices by inserting an ultra-thin chemically active metal nanolayer: a case study on the Ta2O5–Ta system
Authors: Gao Shuang , Zeng Fei , Wang Minjuan , Wang Guangyue , Song Cheng , Pan Feng
Published: April 2015

The nonpolar resistive switching behavior of the Pt/Ta2O5/Pt structure can be transformed into the bipolar and complementary ones by inserting 2 and 4 nm Ta nanolayers, respectively.
Proton ordering dynamics of H2O ice
Authors: Yen Fei , Chi Zhenhua
Published: April 2015

Proton ordering in ice Ih and nucleation of ice XI domains are observed for the first time in undoped H2O and D2O; the ice Ih/II/XI triple point is also identified.
Observable-targeting global cluster structure optimization
Authors: Dieterich Johannes M. , Hartke Bernd
Published: April 2015

Global cluster structure optimization not towards lowest energy but towards best fit of cluster properties to experimental data provides theoretical support for cluster experiments under non-equilibrium conditions.
Correction: A practical approach to calculate the time evolutions of magnetic field effects on photochemical reactions in nano-structured materials
Authors: Yago Tomoaki , Wakasa Masanobu
Published: April 2015

Correction for ‘A practical approach to calculate the time evolutions of magnetic field effects on photochemical reactions in nano-structured materials’ by Tomoaki Yago et al., Phys. Chem. Chem. Phys., 2015, DOI: 10.1039/c5cp00595g.
Solid-phase synthesis of recyclable diphosphine ligands
Authors: Heutz Frank J. L. , Samuels Michiel C. , Kamer Paul C. J.
Published: April 2015

The first efficient solid-phase synthetic approach towards diphosphine ligands is demonstrated. This modular method offers facile access to a class of ligands providing huge potential for ligand fine-tuning.
New donor–acceptor conjugates based on a trifluorenylporphyrin linked to a redox–switchable ruthenium unit
Authors: Merhi Areej , Zhang Xu , Yao Dandan , Drouet Samuel , Mongin Olivier , Paul Frédéric , Williams J. A. Gareth , Fox Mark A. , Paul-Roth Christine O.
Published: April 2015

Spectroelectrochemical studies show four accessible redox states on dyad 3 with the first oxidation process taking place at the Ru(ii) centre and the second oxidation and first reduction processes at the porphyrin centre.
Quantum chemical and solution phase evaluation of metallocenes as reducing agents for the prospective atomic layer deposition of copper
Authors: Dey Gangotri , Wrench Jacqueline S. , Hagen Dirk J. , Keeney Lynette , Elliott Simon D.
Published: April 2015

We propose and evaluate the use of metallocene compounds as reducing agents for the chemical vapour deposition (and specifically atomic layer deposition, ALD) of the transition metal Cu from metalorganic precursors.
Metal–organic frameworks and their derived nanostructures for electrochemical energy storage and conversion
Authors: Xia Wei , Mahmood Asif , Zou Ruqiang , Xu Qiang
Published: April 2015

This review presents a summary of recent progress and strategies in fabricating MOF-based nanostructures for electrochemical applications.
A system level analysis of gastric cancer across tumor stages with RNA-seq data
Authors: Wu Jun , Zhao Xiaodong , Lin Zongli , Shao Zhifeng
Published: April 2015

Gastric cancer is the third leading cause of cancer-related death in the world.
Total synthesis of the pseudopterosin aglycones
Authors: Newton Christopher G. , Sherburn Michael S.
Published: April 2015

The 15 published total syntheses of the pseudopterosins are reviewed, with focus on strategic considerations and an emphasis on ring formation.
Identification of a novel class of covalent modifiers of hemoglobin as potential antisickling agents
Authors: Omar A. M. , Mahran M. A. , Ghatge M. S. , Chowdhury N. , Bamane F. H. A. , El-Araby M. E. , Abdulmalik O. , Safo M. K.
Published: April 2015

Aromatic aldehydes and ethacrynic acid (ECA) exhibit antipolymerization properties that are beneficial for sickle cell disease therapy.
PtAu alloy nanoparticles supported on thermally expanded graphene oxide as a catalyst for the selective oxidation of glycerol
Authors: Yang Gao-Yuan , Shao Shuai , Ke Yi-Hu , Liu Chun-Ling , Ren Hui-Fang , Dong Wen-Sheng
Published: April 2015

Thermally expanded graphene oxide supported PtAu alloy nanoparticles showed high catalytic activity in the oxidation of glycerol in base-free aqueous solution.
A series of two-dimensional microporous triazole-functionalized metal–organic frameworks with the new multi-dentate ligand 1-(4-aminobenzyl)-1,2,4-triazole: single-crystal-to-single-crystal transformation, structural diversity and luminescent sensing
Authors: Wang You You , Jin Qing , Liu Shi Xin , Guo Chao , Liu Yuan Yuan , Ding Bin , Wu Xiang Xia , Li Yan , Zhu Zhao Zhou
Published: April 2015

A new flexible multi-dentate 1-(4-aminobenzyl)-1,2,4-triazole (abtz) ligand has been synthesized, and a series of two-dimensional triazole-functionalized metal–organic frameworks has been isolated.
Template synthesis of NiO ultrathin nanosheets using polystyrene nanospheres and their electrochromic properties
Authors: Zhao Congcong , Chen Cheng , Du Fanglin , Wang Jinmin
Published: April 2015

NiO ultrathin nanosheets synthesized by a template method exhibit fast coloration/bleaching responses.
Label-free and turn-on fluorescent cyanide sensor based on CdTe quantum dots using silver nanoparticles
Authors: Ensafi Ali A. , Kazemifard N. , Rezaei B.
Published: April 2015

A turn-on fluorescence sensor is introduced for determination of trace amount of cyanide, based on glutathione-capped Cd–Te quantum dots.
Silicate bioceramic/PMMA composite bone cement with distinctive physicochemical and bioactive properties
Authors: Chen Lei , Zhai Dong , Huan Zhiguang , Ma Nan , Zhu Haibo , Wu Chengtie , Chang Jiang
Published: April 2015

New bioactive silicate/PMMA composite bone cements possess improved setting properties, high mechanical strength, excellent apatite-mineralization ability and biological activity for injectable bone regeneration materials application.
Al(CH3)3-promoted Pt/MCM-41 catalysts for tetralin hydrogenation in the presence of benzothiophene and promotion mechanism of Al-promoted Pt/MCM-41 catalysts
Authors: Luo Mingjian , Wang Qingfa , Zhang Xiangwen , Wang Li , Hu Bing
Published: April 2015

High platinum dispersion benefits tetralin hydrogenation and sulfur tolerance. Sulfur tolerance is also favourable for electron deficient Ptδ+.
Preparation of “hard-soft” Janus polymeric particles via seeded dispersion polymerization in the presence of n-paraffin droplets
Authors: Hosseinzadeh Soleyman , Saadat Younes
Published: April 2015

A newly emerged class of Janus polymer particles, so-called “hard-soft” ones, were produced using seeded dispersion polymerization (SDP) of 2-ethylhexyl methacrylate (EHMA) with polystyrene (PS) particles in the presence of n-paraffin droplets.
A radiation sensitive hybrid polymer based on an Mn-Anderson polyoxometalate cluster and a UV active organic monomer: synergistic effects lead to improved photocurrent in a photoresponse device
Authors: Kalyani Vishwanath , Satyanarayana V. S. V. , Sarkar Abdus Salam , Kumar Ashwani , Pal Suman K. , Ghosh Subrata , Gonsalves Kenneth E. , Pradeep Chullikkattil P.
Published: April 2015

A new radiation sensitive polyoxometalate/polymer hybrid has been developed which shows good photocurrent generation in a photoresponse device.
A practical anodic oxidation of aminofurazans to azofurazans: an environmentally friendly route
Authors: Sheremetev Aleksei B. , Lyalin Boris V. , Kozeev Andrei M. , Palysaeva Nadezhda V. , Struchkova Marina I. , Suponitsky Kyrill Yu.
Published: April 2015

Nickel oxyhydroxide anode is effective green tools for the electrooxidation of aminofurazans to azofurazans inca. 1% aqueous NaOH at 20 °C. The reaction is simple and convenient, eliminating the use of expensive and toxic organic or inorganic oxidants.
Can the study of self-assembly in solution lead to a good model for the nucleation pathway? The case of tolfenamic acid.
Authors: Du W. , Cruz-Cabeza A. J. , Woutersen S. , Davey R. J. , Yin Q.
Published: April 2015

To further our understanding of the role of solution chemistry in directing nucleation processes new experimental and computational data are presented on the solution and crystallisation chemistry of tolfenamic acid (TA), a benchmark polymorphic compound.
Towards the endothermic dehydrogenation of nanoconfined magnesium borohydride ammoniate
Authors: Yang Yanjing , Liu Yongfeng , Li You , Zhang Xin , Gao Mingxia , Pan Hongge
Published: April 2015

An endothermic dehydrogenation is achieved for Mg(BH4)2·6NH3confined in porous scaffolds with less than 4 nm of pore size.
Tunable Sn structures in porosity-controlled carbon nanofibers for all-solid-state lithium-ion battery anodes
Authors: Nam Dae-Hyun , Kim Ji Woo , Lee Ji-Hoon , Lee So-Yeon , Shin Hae-A-Seul , Lee Se-Hee , Joo Young-Chang
Published: April 2015

Ultra-small tin (Sn) nanoparticle embedded carbon (C) nanofibers are successfully fabricated by porosity control and they exhibit outstanding anode performance in all-solid-state batteries without current collectors and additives.
Sulfur double locked by a macro-structural cathode and a solid polymer electrolyte for lithium–sulfur batteries
Authors: Zhang Cheng , Lin Yue , Liu Jin
Published: April 2015

All-solid-state lithium/sulfur batteries deliver a stable capacity of 910 mA h g−1, which relates to the reversible reduction/oxidation of an intermediate at 2.10 V/2.29 V.
Nickel oxide interlayer films from nickel formate–ethylenediamine precursor: influence of annealing on thin film properties and photovoltaic device performance
Authors: Steirer K. X. , Richards R. E. , Sigdel A. K. , Garcia A. , Ndione P. F. , Hammond S. , Baker D. , Ratcliff E. L. , Curtis C. , Furtak T. , Ginley D. S. , Olson D. C. , Armstrong N. R. , Berry J. J.
Published: April 2015

Decomposition/oxidation correlated to nanoscale c-AFM helps separate selectivity and conductivity.
An extremely thin and robust interconnecting layer providing 76% fill factor in a tandem polymer solar cell architecture
Authors: Martínez-Otero Alberto , Liu Quan , Mantilla-Perez Paola , Bajo Miguel Montes , Martorell Jordi
Published: April 2015

Herein we report a thin and robust interconnecting layer for polymer tandem solar cells where a high fill factor is achieved.
Hierarchically structured MnO2/graphene/carbon fiber and porous graphene hydrogel wrapped copper wire for fiber-based flexible all-solid-state asymmetric supercapacitors
Authors: Zhang Zheye , Xiao Fei , Wang Shuai
Published: April 2015

Two types of fiber-based electrodes, i.e. hierarchically structured MnO2/graphene/carbon fiber and 3D porous graphene hydrogel wrapped copper wire, were successfully fabricated for high performance flexible all-solid-state asymmetric supercapacitors.
Achieving battery-level energy density by constructing aqueous carbonaceous supercapacitors with hierarchical porous N-rich carbon materials
Authors: Yang Mei , Zhong Yiren , Bao Jie , Zhou Xianlong , Wei Jinping , Zhou Zhen
Published: April 2015

3D hierarchical porous N-rich graphitic carbon materials were prepared and further used for symmetric aqueous supercapacitors with battery-level energy density while retaining capacitor-type power density and cycling stability.
Hierarchical worm-like CoS2 composed of ultrathin nanosheets as an anode material for lithium-ion batteries
Authors: Jin Rencheng , Yang Lixia , Li Guihua , Chen Gang
Published: April 2015

Hierarchical worm-like CoS2 assembled by ultrathin nanosheets with an average thickness of 2.1 nm were synthesized by a simple solvothermal process without any surfactant or template.
Fabrication and evaluation of a homogeneous electrospun PCL–gelatin hybrid membrane as an anti-adhesion barrier for craniectomy
Authors: Shi Rui , Xue Jiajia , Wang Hanbin , Wang Renxian , Gong Min , Chen Dafu , Zhang Liqun , Tian Wei
Published: April 2015

An electrospun PCL–gelatin membrane's excellent anti-adhesive properties, biocompatibility and adjustable biodegradable rate make it compatible for applying as an anti-adhesion barrier for craniotomy.
Three-dimensional Fe- and N-incorporated carbon structures as peroxidase mimics for fluorescence detection of hydrogen peroxide and glucose
Authors: Zhang Ruizhong , He Shuijian , Zhang Chunmei , Chen Wei
Published: April 2015

3D Fe- and N-incorporated carbon structures have been synthesized as peroxidase mimics for fluorescence detection of hydrogen peroxide and glucose.
Statistical approach for interpretation of power transformers frequency response analysis results
Authors: Behjat Vahid , Mahvi Mojtaba
Published: April 2015

In spite of many research efforts on fault diagnosis using frequency response analysis (FRA) method, there is still no universally accepted and systematic interpretation technique for these tests and ‘expert opinion’ is often sought when any damaging trend is observed as a result of fault occurrence. This study deals with statistical criteria for interpretation of the FRA results and presents a number of statistical and mathematical indicators that have not been used so far. A measurement setup accompanied by a transformer as a test object, on which winding faults are imposed, completes the test setup for performing the FRA measurements. The parameters are applied to the experimental FRA measurements and the results are compared by a simple normalising equation. Finally, the indicators which are adding more objectivity and transparency to interpretation of the FRA results are presented. Sweep frequency response analysis (SFRA) method is used in this study because of its efficiency and simplicity. It was found through this research work that F‐test, which introduced in this study for the first time, has higher sensitivity, and the differences between the normal and faulty responses of the transformers' windings is more reflected in this parameter compared with the other ones.
Trente ans de collaboration orthodontico-chirurgicale
Authors: Brunel Jean-Michel , Garcia Claude
Published: April 2015

S’intéresser aux dysmorphoses dento-faciales de la part d’un chirurgien, c’est s’ouvrir sur le monde orthodontique et vice versa. La collaboration orthodontico-chirurgicale est inéluctable et représente une véritable synergie. Après avoir évoqué les différents progrès intéressant les deux disciplines, nous insisterons sur l’étroite collaboration devant régner entre nos spécialités. L’exemple du traitement des classes II hyper-divergentes illustrera cette attitude thérapeutique.
La chirurgie orthognathique : de l’indispensable au superflu
Authors: Galletti Catherine
Published: April 2015

La plupart des patients adultes qui consultent pour la réhabilitation d’un sourire ou pour des problèmes fonctionnels pourront être satisfaits en bénéficiant d’un traitement d’orthodontie. Ce traitement, quelque soit la technique orthodontique, sera mené après l’établissement d’un diagnostic et d’un plan de traitement tenant compte de certaines contraintes prothétiques, parodontales ou encore financières. Il existe cependant des situations ou l’équilibre esthétique et fonctionnel est fortement perturbé ou tout simplement impossible à résoudre sans modification des bases osseuses. La chirurgie orthognathique dans ces cas sera incontournable. Nous allons nous intéresser particulièrement, ici, à trois situations couramment rencontrées : les béances, les décalages de classe III et finalement de classe II. Le but de cet article sera de chercher à définir l’intérêt que peuvent représenter ces traitements dits ortho-chirurgicaux, tout en considérant leurs alternatives.
Distraction sagittale du bloc incisivo-canin mandibulaire
Authors: Esnault Olivier
Published: April 2015

L’apport des ostéotomies segmentaires dans les protocoles ortho-chirurgicaux n’est plus à démontrer et retrouve une nouvelle jeunesse grâce à la combinaison avec les techniques de distraction osseuse. L’ostéotomie de Köle, décrite initialement pour fermer des infraclusies antérieures, puis utilisée pour niveler des courbes de Spee très marquées a plus récemment été utilisée pour corriger des encombrements antérieurs. Cette prise en charge s’adresse à des patients porteurs d’une classe II incisive et canine, mais en classe I molaire avec un encombrement mandibulaire isolé. On peut ainsi, au prix d’une préparation orthodontique minimale, créer en 15 jours des diastèmes bilatéraux qui permettront ensuite d’aligner le secteur incisivo-canin sans stripping ni extraction. Les mouvements dentaires orthodontiques peuvent être repris six semaines après la fin de la distraction. Cette technique est donc susceptible d’éviter des extractions de prémolaires et de remplacer certaines ostéotomies sagittales d’avancée par correction du surplomb. Elle permet aussi de corriger une vestibuloversion ou une linguoversion du bloc incisivo-canin en jouant sur l’activation différentielle des vérins et du distracteur. Cette chirurgie segmentaire peut être combinée à des chirurgies de Le Fort 1 avec correction du sens transversal et associée, mais dans un deuxième temps, à une avancée mandibulaire et/ou une génioplastie.
How a short double-stranded DNA bends
Authors: Shin Jaeoh , Lee O-Chul , Sung Wokyung
Published: April 2015

A recent experiment using fluorescence microscopy showed that double-stranded DNA fragments shorter than 100 base pairs loop with the probabilities higher by the factor of 102–106 than predicted by the worm-like chain (WLC) model [R. Vafabakhsh and T. Ha, Science 337, 1101(2012)]. Furthermore, the looping probabilities were found to be nearly independent of the loop size. The results signify a breakdown of the WLC model for DNA mechanics which works well on long length scales and calls for fundamental understanding for stressed DNA on shorter length scales. We develop an analytical, statistical mechanical model to investigate what emerges to the short DNA under a tight bending. A bending above a critical level initiates nucleation of a thermally induced bubble, which could be trapped for a long time, in contrast to the bubbles in both free and uniformly bent DNAs, which are either transient or unstable. The trapped bubble is none other than the previously hypothesized kink, which releases the bending energy more easily as the contour length decreases. It leads to tremendous enhancement of the cyclization probabilities, in a reasonable agreement with experiment.
High efficiency of the spin-orbit torques induced domain wall motion in asymmetric interfacial multilayered Tb/Co wires
Authors: Bang Do , Awano Hiroyuki
Published: April 2015

We investigated current-induced DW motion in asymmetric interfacial multilayered Tb/Co wires for various thicknesses of magnetic and Pt-capping layers. It is found that the driving mechanism for the DW motion changes from interfacial to bulk effects at much thick magnetic layer (up to 19.8 nm). In thin wires, linearly depinning field dependence of critical current density and in-plane field dependence of DW velocity suggest that the extrinsic pinning governs field-induced DW motion and injecting current can be regarded as an effective field. It is expected that the high efficiency of spin-orbit torques in thick magnetic multilayers would have important implication for future spintronic devices based on in-plane current induced-DW motion or switching.
Binding water to a PEG-linked flexible bichromophore: IR spectra of diphenoxyethane-(H2O)n clusters, n = 2-4
Authors: Walsh Patrick S. , Buchanan Evan G. , Gord Joseph R. , Zwier Timothy S.
Published: April 2015

The single-conformation infrared (IR) and ultraviolet (UV) spectroscopies of neutral 1,2-diphenoxyethane-(H2O)n clusters with n = 2-4 (labeled henceforth as 1:n) have been studied in a molecular beam using a combination of resonant two-photon ionization, IR-UV holeburning, and resonant ion-dip infrared (RIDIR) spectroscopies. Ground state RIDIR spectra in the OH and CH stretch regions were used to provide firm assignments for the structures of the clusters by comparing the experimental spectra with the predictions of calculations carried out at the density functional M05-2X/6-31+G(d) level of theory. At all sizes in this range, the water molecules form water clusters in which all water molecules engage in a single H-bonded network. Selective binding to the tgt monomer conformer of 1,2-diphenoxyethane (C6H5-O-CH2-CH2-O-C6H5, DPOE) occurs, since this conformer provides a binding pocket in which the two ether oxygens and two phenyl ring π clouds can be involved in stabilizing the water cluster. The 1:2 cluster incorporates a water dimer “chain” bound to DPOE much as it is in the 1:1 complex [E. G. Buchanan et al., J. Phys. Chem. Lett. 4, 1644 (2013)], with primary attachment via a double-donor water that bridges the ether oxygen of one phenoxy group and the π cloud of the other. Two conformers of the 1:3 cluster are observed and characterized, one that extends the water chain to a third molecule (1:3 chain) and the other incorporating a water trimer cycle (1:3 cycle). A cyclic water structure is also observed for the 1:4 cluster. These structural characterizations provide a necessary foundation for studies of the perturbations imposed on the two close-lying S1/S2 excited states of DPOE considered in the adjoining paper [P. S. Walsh et al., J. Chem. Phys. 142, 154304 (2015)].
Effect of Zr and Nb additions on the high-frequency magnetic properties of Co85-(x+y)Zr3+xNb12+y films
Authors: Endo Yasushi , Ito Tetsuo , Miyazaki Takamichi , Shimada Yutaka , Yamaguchi Masahiro
Published: April 2015

This high-frequency magnetic properties of 250-nm-thick Co85-(x+y)Zr3+xNb12+y (x: 0–5.5, y: 0–11.0) amorphous films are examined as functions of Zr (x) and Nb (y) concentrations. Both x and y influence the high-frequency magnetic properties. In the case of x < 3.0 and y ≤ 5.0, each permeability spectrum appears, but increasing x and y decreases the ferromagnetic resonance (FMR) frequency from 1.20 GHz to 0.41 GHz and increases the effective damping constant from 0.15 to 0.43. For x = 3.0 and y = 8.2, although the permeability spectrum disappears, the effective damping constant is estimated to be approximately 0.82. In contrast, the high-frequency magnetic properties cannot be obtained for x = 5.5 and y = 11.0. Hence, appropriately selecting both Zr and Nb concentrations should effectively control the high-frequency magnetic properties. This finding should be of interest from the viewpoint of new thin film applications, such as microscopic electromagnetic compatibility (EMC), in which properly adjusting the permeability and FMR profiles is vital.
Modeling and analysis of hysteresis by harmonic balance method
Authors: Cheng Weiying , Saito Yoshifuru
Published: April 2015

B-H loop and its modeling are essential for ferromagnetic material characterization and electromagnetic simulation. The objective of this study was to characterize material change by analyzing the corresponding B-H loops and construct a general B-H model for electromagnetic simulation. A B-H loop was decomposed in terms of either ideal or normal magnetization curves, and the respective curves are single-valued functions of B and dB, which can be constructed using harmonic balance method. The B-H loop analysis and modeling were simplified by the loop decomposition approach.
The Shock/Shear platform for planar radiation-hydrodynamics experiments on the National Ignition Facility
Authors: Doss F. W. , Kline J. L. , Flippo K. A. , Perry T. S. , DeVolder B. G. , Tregillis I. , Loomis E. N. , Merritt E. C. , Murphy T. J. , Welser-Sherrill L. , Fincke J. R.
Published: April 2015

An indirectly-driven shock tube experiment fielded on the National Ignition Facility (NIF) was used to create a high-energy-density hydrodynamics platform at unprecedented scale. Scaling up a shear-induced mixing experiment previously fielded at OMEGA, the NIF shear platform drives 130 μm/ns shocks into a CH foam-filled shock tube (∼ 60 mg/cc) with interior dimensions of 1.5 mm diameter and 5 mm length. The pulse-shaping capabilities of the NIF are used to extend the drive for >10 ns, and the large interior tube volumes are used to isolate physics-altering edge effects from the region of interest. The scaling of the experiment to the NIF allows for considerable improvement in maximum driving time of hydrodynamics, in fidelity of physics under examination, and in diagnostic clarity. Details of the experimental platform and post-shot simulations used in the analysis of the platform-qualifying data are presented. Hydrodynamic scaling is used to compare shear data from OMEGA with that from NIF, suggesting a possible change in the dimensionality of the instability at late times from one platform to the other.
Digital microfluidic three-dimensional cell culture and chemical screening platform using alginate hydrogels
Authors: George Subin M. , Moon Hyejin
Published: April 2015

Electro wetting-on-dielectric (EWOD) digital microfluidics (DMF) can be used to develop improved chemical screening platforms using 3-dimensional (3D) cell culture. Alginate hydrogels are one common method by which a 3D cell culture environment is created. This paper presents a study of alginate gelation on EWOD DMF and investigates designs to obtain uniform alginate hydrogels that can be repeatedly addressed by any desired liquids. A design which allows for gels to be retained in place during liquid delivery and removal without using any physical barriers or hydrophilic patterning of substrates is presented. A proof of concept screening platform is demonstrated by examining the effects of different concentrations of a test chemical on 3D cells in alginate hydrogels. In addition, the temporal effects of the various chemical concentrations on different hydrogel posts are demonstrated, thereby establishing the benefits of an EWOD DMF 3D cell culture and chemical screening platform using alginate hydrogels.
Planar Hall ring sensor for ultra-low magnetic moment sensing
Authors: Hung Tran Quang , Terki Ferial , Kamara Souleymanne , Kim Kunwoo , Charar Salam , Kim CheolGi
Published: April 2015

The field sensitivity of a planar Hall effect (PHE) micro-ring type biosensor has been investigated as a function of magnetizing angle of the sensor material, for the sensing of low magnetic moment superparamagnetic labels. The field sensitivity is maximal at a magnetizing angle of α = 20°. At this optimized magnetizing angle, the field sensitivity of a PHE sensor is about 3.6 times higher than that measured at the conventional configuration, α = 90°. This optimization enables the PHE-ring sensor to detect superparamagnetic biolabels with ultra-low magnetic moments down to 4 × 10−13 emu.
Sensing the temperature influence on plasmonic field of metal nanoparticles by photoluminescence of fullerene C60 in layered C60/Au system
Authors: Yeshchenko Oleg A. , Bondarchuk Illya S. , Kozachenko Viktor V. , Losytskyy Mykhaylo Yu.
Published: April 2015

Influence of temperature on the plasmonic field in the temperature range of 78–278 K was studied employing surface plasmon enhanced photoluminescence from the fullerene C60 thin film deposited on 2D array of Au nanoparticles. It was experimentally found that temperature dependence of plasmonic enhancement factor of C60 luminescence decreases monotonically with the temperature increase. Influence of temperature on plasmonic enhancement factor was found to be considerably stronger when the frequency of surface plasmon absorption band of Au nanoparticles and the frequency of fullerene luminescence band are in resonance. Electron-phonon scattering and thermal expansion of Au nanoparticles were considered as two competing physical mechanisms of the temperature dependence of plasmonic field magnitude. The calculations revealed significant prevalence of the electron-phonon scattering. The temperature induced increase in the scattering rate leads to higher plasmon damping that causes the decrease in the magnitude of plasmonic field.
Modular inductive power transmission system for high misalignment electric vehicle application
Authors: Qiu Chun , Chau K. T. , Liu Chunhua , Ching Tze Wood , Zhang Zhen
Published: April 2015

This paper gives a design method of power transmitter for electric vehicle wireless charging applications. Uniform magnetic field is targeted for better modular application and misalignment adaption. Rectangular coil and spiral windings are specially selected for evaluation. The compound winding is chosen for optimization. The magnetic flux density is studied by calculating the mutual inductance per area. By optimally choosing the turns and pitch distances of the spiral winding, a uniform magnetic field is achieved. Using finite element analysis, the performances of the transmitter are evaluated, including its tolerance to misalignment.
Modeling optical properties of silicon clusters by first principles: From a few atoms to large nanocrystals
Authors: Nurbawono Argo , Liu Shuanglong , Zhang Chun
Published: April 2015

Time dependent density functional tight binding (TDDFTB) method is implemented with sparse matrix techniques and improved parallelization algorithms. The method is employed to calculate the optical properties of various Si nanocrystals (NCs). The calculated light absorption spectra of small Si NCs from TDDFTB were found to be comparable with many body perturbation methods utilizing planewave basis sets. For large Si NCs (more than a thousand atoms) that are beyond the reach of conventional approaches, the TDDFTB method is able to produce reasonable results that are consistent with prior experiments. We also employed the method to study the effects of surface chemistry on the optical properties of large Si NCs. We learned that the optical properties of Si NCs can be manipulated with small molecule passivations such as methyl, hydroxyl, amino, and fluorine. In general, the shifts and profiles in the absorption spectra can be tuned with suitably chosen passivants.
Representation of macroscopic magnetization based on bifurcation property of domain structure
Authors: Nakamura T. , Ito S. , Mifune T. , Matsuo T. , Kaido C.
Published: April 2015

This study presents an efficient representation of macroscopic magnetization process based on the bifurcation property of mesoscopic two-domain magnetic particles. The macroscopic magnetization model, called the assembled domain structure model (ADSM), is constructed by assembling mesoscopic particles. Bifurcation is discussed of the two-domain state from the single-domain state in the unit mesoscopic particle in the ADSM. Based on this state bifurcation, a procedure to switch the macroscopic magnetization-state transition in the ADSM is developed, which dramatically reduces computation times in macroscopic magnetization simulations.
Fabrication of nanochannels on polystyrene surface
Authors: Peng Ran , Li Dongqing
Published: April 2015

Solvent-induced nanocrack formation on polystyrene surface is investigated experimentally. Solubility parameter and diffusion coefficient of alcohols are employed to elucidate the swelling and cracking processes as well as the crack size. Experimental results show that the crack size increases with the heating temperature, heating time, and the concentration and volume of the alcohols. A guideline on fabricating single smaller nanocracks on polymers by solvent-induced method is provided. Nanocracks of approximately 64 nm in width and 17.4 nm in depth were created and replicated onto PDMS (polydimethylsiloxane) slabs to form nanochannels.
Thermodynamic analysis of binary Fe85B15 to quinary Fe85Si2B8P4Cu1 alloys for primary crystallizations of α-Fe in nanocrystalline soft magnetic alloys
Authors: Takeuchi A. , Zhang Y. , Takenaka K. , Makino A.
Published: April 2015

Fe-based Fe85B15, Fe84B15Cu1, Fe82Si2B15Cu1, Fe85Si2B12Cu1, and Fe85Si2B8P4Cu1 (NANOMET®) alloys were experimental and computational analyzed to clarify the features of NANOMET that exhibits high saturation magnetic flux density (Bs) nearly 1.9 T and low core loss than conventional nanocrystalline soft magnetic alloys. The X-ray diffraction analysis for ribbon specimens produced experimentally by melt spinning from melts revealed that the samples were almost formed into an amorphous single phase. Then, the as-quenched samples were analyzed with differential scanning calorimeter (DSC) experimentally for exothermic enthalpies of the primary and secondary crystallizations (ΔHx1 and ΔHx2) and their crystallization temperatures (Tx1 and Tx2), respectively. The ratio ΔHx1/ΔHx2 measured by DSC experimentally tended to be extremely high for the Fe85Si2B8P4Cu1 alloy, and this tendency was reproduced by the analysis with commercial software, Thermo-Calc, with database for Fe-based alloys, TCFE7 for Gibbs free energy (G) assessments. The calculations exhibit that a volume fraction (Vf) of α-Fe tends to increase from 0.56 for the Fe85B15 to 0.75 for the Fe85Si2B8P4Cu1 alloy. The computational analysis of the alloys for G of α-Fe and amorphous phases (Gα-Fe and Gamor) shows that a relationship Gα-Fe ∼ Gamor holds for the Fe85Si2B12Cu1, whereas Gα-Fe < Gamor for the Fe85Si2B8P4Cu1 alloy at Tx1 and that an extremely high Vf = 0.75 was achieved for the Fe85Si2B8P4Cu1 alloy by including 2.8 at. % Si and 4.5 at. % P into α-Fe. These computational results indicate that the Fe85Si2B8P4Cu1 alloy barely forms amorphous phase, which, in turn, leads to high Vf and resultant high Bs.
Complex additive systems for Mn-Zn ferrites with low power loss
Authors: Töpfer J. , Angermann A.
Published: April 2015

Mn-Zn ferrites were prepared via an oxalate-based wet-chemical synthesis process. Nanocrystalline ferrite powders with particle size of 50 nm were sintered at 1150 °C with 500 ppm CaO and 100 ppm SiO2 as standard additives. A fine-grained, dense microstructure with grain size of 4–5 μm was obtained. Simultaneous addition of Nb2O5, ZrO2, V2O5, and SnO2 results low power losses, e.g., 65 mW/cm3 (500 kHz, 50 mT, 80 °C) and 55 mW/cm3 (1 MHz, 25 mT, 80 °C). Loss analysis shows that eddy current and residual losses were minimized through formation of insulating grain boundary phases, which is confirmed by transmission electron microscopy. Addition of SnO2 increases the ferrous ion concentration and affects anisotropy as reflected in permeability measurements μ(T).
Magnetic anisotropy modulation of epitaxial Fe3O4 films on MgO substrates
Authors: Chichvarina O. , Herng T. S. , Xiao W. , Hong X. , Ding J.
Published: April 2015

Fe3O4 has been widely studied because of its great potential in spintronics and other applications. As a magnetic electrode, it is highly desired if magnetic anisotropy can be controlled. Here, we report the results from our systematic study on the magnetic properties of magnetite (Fe3O4) thin films epitaxially grown on various MgO substrates. Strikingly, we observed a prominent perpendicular magnetic anisotropy in Fe3O4 film deposited on MgO (111) substrate. When measured in out-of-plane direction, the film (40 nm thick) exhibits a well-defined square hysteresis loop with coercivity (Hc) above 1 kOe, while much lower coercivity was obtained in the in-plane orientation. In sharp contrast, the films deposited onto MgO (100) and MgO (110) substrates show in-plane magnetic anisotropy. These films exhibit a typical soft magnet characteristic—Hc lies within the range of 200–400 Oe. All the films showed a clear Verwey transition near 120 K—a characteristic of Fe3O4 material. In addition, a series of magnetoresistance (MR) measurements is performed and the MR results are in good agreement with the magnetic observations. The role of the substrate orientation and film thickness dependency is also investigated.
Fe-Pt thick-film magnets prepared by electroplating method
Authors: Yanai T. , Furutani K. , Ohgai T. , Nakano M. , Suzuki K. , Fukunaga H.
Published: April 2015

Fe-Pt thick-films were electroplated on Ta substrates using a direct current, and the magnetic properties of the film were evaluated. The Fe-Pt films with the thickness from 3 to 23 μm were obtained by changing in the plating time from 2 to 20 min. As the as-plated Fe-Pt films had the disordered fcc (face-centered-cubic) structure and low coercivity (<5 kA/m), we annealed the films at 700 °C for 60 min. The annealing induced the phase transformation from fcc structure to fct (face-centered-tetragonal) one, and we consequently obtained the Fe50Pt50 thick-films with large coercivity of approximately 700 kA/m. The large coercivity was observed in the wide thickness range for our experimental conditions. Therefore, we concluded that our prepared Fe-Pt film is one of the attractive thick-film magnets.
The origin of thermally stimulated depolarization currents in multiferroic CuCrO2
Authors: Ngo T. N. M. , Adem U. , Palstra T. T. M.
Published: April 2015

We have measured the thermally stimulated depolarization currents (TSDC) of multiferroic CuCrO2. We observe a sharp peak near the antiferromagnetic ordering temperature TN ∼ 24 K, below which the material becomes ferroelectric. In addition, we observe three other peaks above TN at ∼50, 120, and 150 K, when the poling is done at a higher temperature than TN. These peaks are not related to exotic kinds of ferroelectricity. Using the poling field dependence of TSDC, the origins of the first two peaks are ascribed to the relaxation of defect dipoles and to space charge relaxation due to the release of trapped charges, respectively. Upon polishing, the peaks observed at 120 and 150 K disappear, suggesting a surface defect origin. Moreover, using temperature and frequency dependent dielectric measurements, we find Maxwell–Wagner type dielectric relaxation. In connection with the mechanism of one of the TSDC peaks, we suggest a Schottky barrier formation to explain the dielectric relaxation.
Core-shell hydrogel beads with extracellular matrix for tumor spheroid formation
Authors: Yu L. , Grist S. M. , Nasseri S. S. , Cheng E. , Hwang Y.-C. E. , Ni C. , Cheung K. C.
Published: April 2015

Creating multicellular tumor spheroids is critical for characterizing anticancer treatments since they may provide a better model of the tumor than conventional monolayer culture. Moreover, tumor cell interaction with the extracellular matrix can determine cell organization and behavior. In this work, a microfluidic system was used to form cell-laden core-shell beads which incorporate elements of the extracellular matrix and support the formation of multicellular spheroids. The bead core (comprising a mixture of alginate, collagen, and reconstituted basement membrane, with gelation by temperature control) and shell (comprising alginate hydrogel, with gelation by ionic crosslinking) were simultaneously formed through flow focusing using a cooled flow path into the microfluidic chip. During droplet gelation, the alginate acts as a fast-gelling shell which aids in preventing droplet coalescence and in maintaining spherical droplet geometry during the slower gelation of the collagen and reconstituted basement membrane components as the beads warm up. After droplet gelation, the encapsulated MCF-7 cells proliferated to form uniform spheroids when the beads contained all three components: alginate, collagen, and reconstituted basement membrane. The dose-dependent response of the MCF-7 cell tumor spheroids to two anticancer drugs, docetaxel and tamoxifen, was compared to conventional monolayer culture.
Effect of magnetic field enhancement of the photocurrent in ferromagnetic metal-dielectric heterostructures SiO2(Co)/GaAs
Authors: Pavlov V. V. , Lutsev L. V. , Usachev P. A. , Astretsov A. A. , Stognij A. I. , Novitskii N. N. , Pisarev R. V.
Published: April 2015

Heterostructures of silicon dioxide films containing cobalt nanoparticles SiO2(Co) grown on GaAs substrate exhibit at room temperature high values of magnetic field enhancement of photocurrent in the vicinity and above the GaAs bandgap of ∼1.4 eV. For photon energies E above the GaAs bandgap, the photocurrent significantly increases, while the avalanche process is suppressed by the magnetic field, and the current flowing through the heterostructure decreases. The photocurrent is enhanced in the SiO2(Co 60 at. %)/GaAs heterostructure at the magnetic field H = 1.65 kOe by a factor of about ten for the photon energy E = 1.5 eV. This phenomenon is explained by a model describing electronic transitions in magnetic fields with the spin-dependent recombination process at deep impurity centers in the GaAs interface region.
The diet of the common wombat (Vombatus ursinus) above the winter snowline in the decade following a wildfire
Authors: Green K. , Davis N. E. , Robinson W. A.
Published: April 2015

The use of high elevations with deep snow cover presents a challenge to mammalian herbivores, which is exacerbated by subalpine vegetation dynamics such as slow regrowth following disturbance. We postulated that post-fire responses of common wombats (Vombatus ursinus) at high elevations would differ from those at low elevations. We examined the winter diet of common wombats in the Snowy Mountains in the decade after fire in burnt and unburnt areas and compared our results to published diet studies from low elevations. Optimal foraging theory predicts that as food resources become scarce herbivores respond by widening their choice of foods, yet we found that wombats have only marginally wider dietary breadth at higher than at lower elevations in terms of plant forms and diet breadth in terms of species was not greater. The use of shrubs and the tall herb Dianella tasmanica enables wombats to reduce the energetic costs of digging for food in snow. Able to survive fire in a burrow, the wombat is then capable of responding to reduced foraging opportunities following fire by broadening the range of species consumed and adopting foraging strategies that exploit temporally improved food quality, demonstrated by the greater proportion of grass consumed in burnt sites.
Road-kills of the giant anteater in south-eastern Brazil: 10 years monitoring spatial and temporal determinants
Authors: de Freitas Carlos H. , Justino Carla S. , Setz Eleonore Z. F.
Published: April 2015

Context The giant anteater, Myrmecophaga tridactyla, is a large insectivorous mammal from Cerrado which is classified as vulnerable by the IUCN‘s red list. In spite of frequent giant anteater casualties, there continues to be a lack of published data on how road and landscape attributes affect road-kill rates – information that could prove useful in guiding mitigation measures. Aims We seek to determine whether road and landscape attributes influence the incidence of road-kills of the giant anteater. Methods From February 2002 to December 2012 (except for 2004), five roads in two regions in south-eastern Brazil were surveyed twice each month by car. We recorded temporal road-kill data for the giant anteater and related spatial road variables. These variables were also recorded at regular control sites every 2 km. We also took traffic volume data on stretches of the two roads to correlate with road-kills. Key results Of the 45 anteater casualties recorded, there was a predominance of adult males. On roads MG-428 and SP-334, we found anteater road-kills were more common in the dry season, negatively correlated with traffic volume and related to the presence of native vegetation. Accordingly, road-kill sites tended to occur near the cerrado and grasslands and also appeared more frequently on some straight stretches of roadways. Although it was not shown to influence road-kill rates, topography data does point to regular overpass/underpass locations allowing population connectivity. Termitaria or ant nests were present at all road-kill sites, with 86% having signs of feeding. Conclusions Native vegetation along roadways, together with straight road design, increases the probability of anteater road-kills by 40.1%. Implications For mitigation, mowing and removing insect nests on roadsides, as well as roadside wildlife fencing in cerrado and grassland areas is suggested. Warning signs and radar to reduce vehicle speed are recommended for both human safety and anteater conservation. With regard to population connectivity, the absence of aggregated anteater road-kill data in this study meant that there were no particular crossing locations identified. However, the collected topography data do show places that could be used for roadway crossings. The measures indicated may apply to similar species and types of topography on other continents.