bluuebunny/crossref_metadata_2025 huggingface dataset:
Anthraquinones and flavonoids of Cassia tora leaves ameliorate sodium selenite induced cataractogenesis in neonatal rats
Authors: Sreelakshmi V. , Abraham Annie
Published: January 2016

The present study was undertaken to evaluate the efficacy ofCassia toraleaves, an edible plant traditionally used for eye ailments, in preventing experimental cataractogenesis.
Stoichiometric control of live cell mixing to enable fluidically-encoded co-culture models in perfused microbioreactor arrays
Authors: Occhetta P. , Glass N. , Otte E. , Rasponi M. , Cooper-White J. J.
Published: January 2016

A cell mixer microbioreactor array platform that permits the rapid establishment of perfused cell co-culture models in a high-throughput, programmable fashion.
A fully integrated paperfluidic molecular diagnostic chip for the extraction, amplification, and detection of nucleic acids from clinical samples
Authors: Rodriguez Natalia M. , Wong Winnie S. , Liu Lena , Dewar Rajan , Klapperich Catherine M.
Published: January 2016

We present a low-cost, disposable, and fully-integrated paperfluidic molecular diagnostic chip for sample-to-result functionality at the point-of-care.
Effect of pretreatment on the enzymatic synthesis of rosin acid starch
Authors: Li He , Lin Rihui , He Junbin , Long Han , Liao Wei , Chen Qiyong
Published: January 2016

Esterification reaction efficiency was improved by pretreatment of starch, and the high DS of RAS was achieved.
Double bond terminated Ln3+-doped LiYF4 nanocrystals with strong single band NIR emission: simple click chemistry route to make water dispersible nanocrystals with various functional groups
Authors: Meesaragandla Brahmaiah , Sarkar Debashrita , Adusumalli Venkata N. K. B. , Mahalingam Venkataramanan
Published: January 2016

A simple thiol–ene click chemistry strategy to develop upconverting nanocrystals with different functional groups.
Isatin-based three-component synthesis of new spirooxindoles using magnetic nano-sized copper ferrite
Authors: Baghernejad Mojtaba , Khodabakhshi Saeed , Tajik Sanaz
Published: January 2016

CuFe2O4 nanoparticles were synthesized and employed as highly efficient catalysts in the three-component synthesis of biologically important spirooxindoles.
A 3D electrochemical immunodevice based on an Au paper electrode and using Au nanoflowers for amplification
Authors: Wang Xiu , Deng Wenping , Shen Lei , Yan Mei , Yu Jinghua
Published: January 2016

A highly sensitive electrochemical immunosensor combined with a 3D origami device for detection of cancer antigen was developed based on a novel Au nanoparticle-modified paper working electrode.
Topologically protected Dirac plasmons and their evolution across the quantum phase transition in a (Bi1−xInx)2Se3topological insulator
Authors: Autore Marta , Giorgianni Flavio , D’ Apuzzo Fausto , Di Gaspare Alessandra , Lo Vecchio Irene , Brahlek Matthew , Koirala Nikesh , Oh Seongshik , Schade Urlich , Ortolani Michele , Lupi Stefano
Published: January 2016

We report on the plasmonic behavior across the quantum-phase transition among a Topological Insulator and a trivial insulator.
Iso-oriented monolayer α-MoO3(010) films epitaxially grown on SrTiO3(001)
Authors: Du Yingge , Li Guoqiang , Peterson Erik W. , Zhou Jing , Zhang Xin , Mu Rentao , Dohnálek Zdenek , Bowden Mark , Lyubinetsky Igor , Chambers Scott A.
Published: January 2016

Iso-oriented α-MoO3(010) films with a monolayer thickness can be grown on SrTiO3(001) substrate by molecular beam epitaxyviaa self-limiting mechanism.
Interaction grand potential between calcium–silicate–hydrate nanoparticles at the molecular level
Authors: Bonnaud Patrick A. , Labbez Christophe , Miura Ryuji , Suzuki Ai , Miyamoto Naoto , Hatakeyama Nozomu , Miyamoto Akira , Van Vliet Krystyn J.
Published: January 2016

Mean forces and interaction grand potentials between calcium–silicate–hydrate particles.
Planar plasmonic chiral nanostructures
Authors: Zu Shuai , Bao Yanjun , Fang Zheyu
Published: January 2016

A strong chiral optical response induced at a plasmonic Fano resonance in a planar Au heptamer nanostructure was experimentally and theoretically demonstrated.
Synthesis of tetra-substituted 5-trifluoromethylpyrazoles via sequential halogenation/palladium-catalyzed C–C and C–N cross-coupling
Authors: Wiethan Carson , Rosa Wilian C. , Bonacorso Helio G. , Stradiotto Mark
Published: January 2016

The assembly of tetra-substituted 5-trifluoromethylpyrazoles is presented, involving palladium-catalyzed Negishi or Buchwald–Hartwig cross-couplings to install carbon or nitrogen-based 4-substituents.
Palladium-catalyzed direct C–H arylation of pyridine N-oxides with potassium aryl- and heteroaryltrifluoroborates
Authors: Li Mengli , Li Xing , Chang Honghong , Gao Wenchao , Wei Wenlong
Published: January 2016

An efficient ligand-free Pd(OAc)2-catalyzed selective arylation of pyridine N-oxides using potassium (hetero)aryltrifluoroborates as coupling partners via C–H bond activation was achieved in the presence of TBAI.
Oxidative ring-opening of ferrocenylcyclopropylamines to N-ferrocenylmethyl β-hydroxyamides
Authors: Gee Yi Sing , Goertz Neils J. M. , Gardiner Michael G. , Hyland Christopher J. T.
Published: January 2016

Thein situreduction of ferrocenyl cyclopropylimines to the corresponding amines triggers a facile oxidative ring-opening to yield the formal four-electron oxidation products:N-ferrocenylmethyl β-hydroxyamides.
Synthesis and properties of couplable ABCDE star copolymers by orthogonal CuAAC and Diels–Alder click reactions
Authors: Liu Huanhuan , Pan Weidong , Tong Min , Zhao Youliang
Published: January 2016

Well-defined ABCDE star quintopolymers generated by a modular and orthogonal strategy could self-assemble into intriguing nanoobjects sensitive to thermal and pH stimuli.
Preparation of inverse polymerized high internal phase emulsions using an amphiphilic macro-RAFT agent as sole stabilizer
Authors: Khodabandeh Aminreza , Dario Arrua R. , Desire Christopher T. , Rodemann Thomas , Bon Stefan A. F. , Thickett Stuart C. , Hilder Emily F.
Published: January 2016

Oil-in-water (‘inverse’) High Internal Phase Emulsions (HIPEs) have been prepared using an amphiphilic macro-RAFT agent with toluene as the internal dispersed phase (∼80 vol%) and an aqueous monomer solution as the continuous phase.
Controlling molecular weight and polymer architecture during the Passerini three component step-growth polymerization
Authors: Oelmann S. , Solleder S. C. , Meier M. A. R.
Published: January 2016

A new approach to control the molecular weight and polymer architecture using the Passerini three-component step-growth polymerization is described.
Visible-light promoted intermolecular halofunctionalization of alkenes with N-halogen saccharins
Authors: Song Lu , Luo Sanzhong , Cheng Jin-Pei
Published: January 2016

A simple and efficient visible-light promoted intermolecular haloamination and haloetherification of alkenes was reported.
A unique cooperative catalytic system carrying metallic iron and 2-hydroxyethyl 2-bromoisobutyrate for the controlled/living ring-opening polymerization of ε-caprolactone
Authors: Shang Xiu-Juan , Zhang Wen-Hua , Lang Jian-Ping
Published: January 2016

Iron and 2-hydroxyethyl 2-bromoisobutyrate cooperatively initiates the ε-caprolactone polymerization, yielding polymers with high molecular weight and narrow molecular weight distribution.
Active corrosion protection coating for a ZE41 magnesium alloy created by combining PEO and sol–gel techniques
Authors: Ivanou D. K. , Yasakau K. A. , Kallip S. , Lisenkov A. D. , Starykevich M. , Lamaka S. V. , Ferreira M. G. S. , Zheludkevich M. L.
Published: January 2016

A composite “self-healing” corrosion protection coating with high barrier properties was created on a Mg alloy by combining PEO and sol–gel techniques.
Simultaneous preconcentration of uranium and thorium in aqueous samples using cloud point extraction
Authors: Saha Abhijit , Deb Sadhan Bijoy , Sarkar Arnab , Saxena Manoj Kumar , Tomar B. S.
Published: January 2016

Simultaneous cloud point extraction of uranium and thorium in aqueous samples with the highest reported extraction efficiencies and preconcentration factors.
Wet electrospun silk fibroin/gold nanoparticle 3D matrices for wound healing applications
Authors: Akturk Omer , Kismet Kemal , Yasti Ahmet C. , Kuru Serdar , Duymus Mehmet E. , Kaya Feridun , Caydere Muzaffer , Hucumenoglu Sema , Keskin Dilek
Published: January 2016

The effectiveness of a silk fibroin/gold nanoparticle 3D nanofibrous matrix on a rat model of full-thickness dermal wound healing was investigated.
Synthesis of 4-phenyl-5,6-dihydrobenzo[h]quinazolines and their evaluation as growth inhibitors of carcinoma cells
Authors: Maurya Hardesh K. , Hasanain Mohammad , Singh Sarita , Sarkar Jayanta , Dubey Vijaya , Shukla Aparna , Luqman Suaib , Khan Feroz , Gupta Atul
Published: January 2016

The synthesis of various benzo[h]quinazoline analogs was accomplished through the reaction of chalcone with guanidine. The synthesized compounds were screened for their anticancer potential against different cancer cells.
Toward hemocompatible self-assembling antimicrobial nanofibers: understanding the synergistic effect of supramolecular structure and PEGylation on hemocompatibility
Authors: Xu Dawei , Ran Qian , Xiang Yang , Jiang Linhai , Smith Britannia M. , Bou-Abdallah Fadi , Lund Reidar , Li Zhongjun , Dong He
Published: January 2016

In this work we will demonstrate the supramolecular assembly of antimicrobial peptides and the effect of PEGylation and nanostructure on biocompatibility with human red blood cells.
Synthesis of MoS2 nanosheet supported Z-scheme TiO2/g-C3N4 photocatalysts for the enhanced photocatalytic degradation of organic water pollutants
Authors: Jo Wan-Kuen , Adinaveen T. , Vijaya J. Judith , Sagaya Selvam N. Clament
Published: January 2016

MoS2 nanosheets loaded with Z-scheme TiO2/g-C3N4 photocatalysts were prepared using a wetness impregnation method.
Compromising high strength and ductility in nanoglass–metallic glass nanolaminates
Authors: Adibi Sara , Branicio Paulo S. , Ballarini Roberto
Published: January 2016

Large-scale molecular-dynamics simulations are used to investigate the mechanical properties of 50 nm diameter Cu64Zr36 nanolaminate nanopillars constructed from 5 nm thick layers of metallic glass (MG) or MG and 5 nm grain sized nanoglass.
A novel highly ordered mesoporous carbon-based solid acid for synthesis of bisphenol-A
Authors: Dong Xiuqin , Jiang Yuan , Shan Wenbin , Zhang Minhua
Published: January 2016

Effect of different catalysts on phenol–acetone condensation reaction.
Polyacrylonitrile-based turbostratic graphite-like carbon wrapped silicon nanoparticles: a new-type anode material for lithium ion battery
Authors: Dong Xiaozhong , Lu Chunxiang , Wang Liyong , Zhou Pucha , Li Denghua , Wang Lu , Wu Gangping , Li Yonghong
Published: January 2016

The carbonaceous matrix formed by PAN-based turbostratic graphite-like carbon could give full play to the lithium-intercalation ability of Si nanoparticles.
Microwave-assisted preparation of SO42− intercalated hydrotalcites for ammonia–nitrogen removal
Authors: Chen Chao-Rong , Zeng Hong-Yan , Xu Sheng , Liu Xiao-Jun , Xiao Hua-Miao , Duan Heng-Zhi
Published: January 2016

Microwave (MW) assisted preparation of SO42− intercalated hydrotalcites (S-RLDH-MW) at different temperatures.
Direct writing of stable Cu–Ag-based conductive patterns for flexible electronics
Authors: Li Wei , Li Wenjiang , Wang Mengmeng , Liu Guoxu , Chen Minfang
Published: January 2016

Particle packing density and sintering method are important to improve patterns' conductivity and mechanical properties at a low temperature 160 °C.
Stereocomplex poly(lactic acid) nanoparticles crystallized through nanoporous membranes and application as nucleating agent
Authors: Uehara Hiroki , Ishizuka Mina , Tanaka Hidekazu , Kano Makiko , Yamanobe Takeshi
Published: January 2016

Stereocomplex crystallization of poly(l-lactic acid) (PLLA) and poly(d-lactic acid) (PDLA) was performed by flowing their blended solution through nano-channels of porous membranes.
One-step sol–gel synthesis of hierarchically porous, flow-through carbon/silica monoliths
Authors: Katiyar Shishir , Mondal Kunal , Sharma Ashutosh
Published: January 2016

A novel synthesis of hierarchically porous, flow-through carbon/silica composite monoliths with ultra-high surface areas (~2600 m2 g−1), tunable porosity in micro/meso/macro-structured domains, and in situ growth of silver nanoparticles has been shown for catalytic use.
Design of three dimensional hybrid Co3O4@NiMoO4 core/shell arrays grown on carbon cloth as high-performance supercapacitors
Authors: Li Yongfeng , Wang Hui , Jian Jianming , Fan Yun , Yu Lin , Cheng Gao , Zhou Junli , Sun Ming
Published: January 2016

Electrodes with rationally designed hybrid nanostructure composites can have superior electrochemical performance for supercapacitors to single structured materials.
A new Pseudomonas quinolone signal (PQS) binding partner: MexG
Authors: Hodgkinson James T. , Gross Jeremy , Baker Ysobel R. , Spring David R. , Welch M.
Published: January 2016

Pseudomonas Quinolone Signal (PQS) probes capture a new binding partner for this signal molecule.
Unprotected and interconnected Ru0 nano-chain networks: advantages of unprotected surfaces in catalysis and electrocatalysis
Authors: Anantharaj S. , Jayachandran M. , Kundu Subrata
Published: January 2016

Surfactant- and support-free metallic, interconnected and unprotected Ru nano-chain networks are synthesized and screened for catalytic nitro arene hydrogenation and OER studies. Their excellent catalytic and electrocatalytic activities are due to the advantages of having unprotected Ru0 surfaces.
Experimental and computational study of alkane dehydrogenation catalyzed by a carbazolide-based rhodium PNP pincer complex
Authors: Bézier David , Guan Changjian , Krogh-Jespersen Karsten , Goldman Alan S. , Brookhart Maurice
Published: January 2016

A rhodium complex based on the bis-phosphine carbazolide pincer ligand was investigated in the context of alkane dehydrogenation and in comparison with its iridium analogue.
Volumetric variation confinement: surface protective structure for high cyclic stability of lithium metal electrodes
Authors: Peng Zhe , Wang Shuwei , Zhou Jingjing , Jin Yan , Liu Yang , Qin Yinping , Shen Cai , Han Weiqiang , Wang Deyu
Published: January 2016

A composite surface protective structure keeps Li metal from electrolyte attack and enables coulombic efficiency as high as 97–99%.
Response to the comment on “Promising blood-derived biomarkers for estimation of the postmortem interval”
Authors: Dinis-Oliveira Ricardo Jorge , Carvalho Félix , Costa Isabel , Silvestre Ricardo , Magalhães Teresa
Published: January 2016

Following Meurs and Szykuła's comment on our published article titled “Promising blood-derived biomarkers for estimation of the postmortem interval”, we recognize the importance of the issues raised, but we would like to emphasize that these contain some misinterpretations and that most of the points were already discussed in depth in our manuscript particularly in the conclusion section. We also aim to highlight further data regarding the difficulties of postmortem interval estimation.
A remote coordination booster enhances the catalytic efficiency by accelerating the generation of an active catalyst
Authors: Gupta Suraj K. , Choudhury Joyanta
Published: January 2016

A RuII(terpy)2 unit incorporated remotely to the catalytic site acts as a “coordination booster” for enhancing the catalytic efficiency to achieve excellent performance in the selective oxidative transformation of alkenes and alkynes to carbonyl compounds.
The Evans Aldol–Prins cyclization: a general and stereoselective method for the synthesis of 2,3,4,5,6-pentasubstituted tetrahydropyrans
Authors: Álvarez-Méndez Sergio J. , García Celina , Martín Víctor S.
Published: January 2016

A method for the synthesis of 2,3,4,5,6-pentasubstituted THPs with good yields and diastereoselectivities through an Evans Aldol–Prins strategy is described.
Enhanced product selectivity promoted by remote metal coordination in acceptor-free alcohol dehydrogenation catalysis
Authors: Valencia Marta , Müller-Bunz Helge , Gossage Robert A. , Albrecht Martin
Published: January 2016

A bimetallic [Ir3+]2 complex was synthesized based on a bridging 1,2,3-triazole ligand that coordinates to one Cp*Ir unit as N,N-bidentate chelate, and to the other as a C,C-bidentate ligand.
Correction: A highly enantioselective Biginelli reaction using self-assembled methanoproline–thiourea organocatalysts: asymmetric synthesis of 6-isopropyl-3,4-dihydropyrimidines
Authors: Hang Zhijun , Zhu Jun , Lian Xiang , Xu Peng , Yu Han , Han Sheng
Published: January 2016

Correction for ‘A highly enantioselective Biginelli reaction using self-assembled methanoproline–thiourea organocatalysts: asymmetric synthesis of 6-isopropyl-3,4-dihydropyrimidines’ by Zhijun Hanget al.,Chem. Commun., 2016,52, 80–83.
Trihaloethenes as versatile building blocks for organic synthesis
Authors: Grossmann Adriana S. , Magauer Thomas
Published: January 2016

Trihaloethenes are versatile C2-building blocks that can be simply modified via addition, elimination and transition metal-catalyzed reactions.
Peganumine B-I and two enantiomers: new alkaloids from the seeds of Peganum harmala Linn. and their potential cytotoxicity and cholinesterase inhibitory activities
Authors: Yang Ya-di , Cheng Xue-mei , Liu Wei , Han Zhu-zhen , Chou Gui-xin , Wang Ying , Sun Du-xin , Wang Zheng-tao , Wang Chang-hong
Published: January 2016

Ten new alkaloids (peganumine B-I and two enantiomers), containing five β-carbolines, three quinazolones, two compounds with both of the above skeletons, and one amphoteric alkaloid with a four-membered ring, were isolated from Peganum harmala.
Exploiting photooxygenations mediated by porphyrinoid photocatalysts under continuous flow conditions
Authors: de Oliveira Kleber T. , Miller L. Zane , McQuade D. Tyler
Published: January 2016

Photooxygenations of naphthols under continuous flow conditions using porphyrinoids as photocatalysts are described. Reaction conditions, long-term experiments and scope were performed, thus allowing the production of substituted naphthoquinones.
Proton-triggered switch based on a molecular transistor with edge-on gate
Authors: Li Lianwei , Lo Wai-Yip , Cai Zhengxu , Zhang Na , Yu Luping
Published: January 2016

The effect of protonation on the molecular electronic properties of five pyridinoparacyclophane (PPC)-based molecular wires was investigated. The protonation/deprotonation process can reversibly switch the electronic properties of the molecules.
Islanding detection method based on a new approach to voltage phase angle of constant power inverters
Authors: Pourbabak Hajir , Kazemi Ahad
Published: January 2016

This study presents a new islanding detection approach using the notion of active methods. A difference between the instantaneous and nominal voltage phase angle (VPA) of a distributed generation (DG) is applied to inverter‐based interface control. After the islanding phenomenon, currents id and iq will be changed by adding the variation of the point of common coupling VPA to input of d–q transformation block of currents. This subsequently causes the voltage and frequency deviations using for detecting island. Active islanding detection techniques usually leave adverse effects on power quality. The considerable advantages of the proposed method include insignificant negative effects on the power quality in the normal operation of the power system. The performance of the proposed islanding detection method is evaluated by some common test presented in UL1741; in addition, the results of some tests are presented for multiple DGs that show the proposed method does not cause significant interference between two DGs in the operational mode. Analogous to the case of a single DG, the island was also detected well in the case of multiple DGs.
Reliable integration of a concentrating solar power plant in a small isolated system through an appropriately sized battery energy storage system
Authors: Nikolaidis Alexandros I. , Koumparou Yiannis , Makrides Georgios , Efthymiou Venizelos , Georghiou George Elia , Charalambous Charalambos A.
Published: January 2016

This study details a comprehensive storage‐sizing methodology to allow a concentrating solar power plant to reliably integrate in the Cyprus power system which is classified as small and isolated. The need for providing a storage solution arises from the fact that large quantities of renewable energy sources may impose certain challenges on how isolated systems operate. Developing solutions to these challenges will enable higher penetrations of renewable generation sources on such systems and the future growth of renewable energy. To this extent, the methodology described in this study pertains to clear and explicit steps required to provide sufficient evidence toward the reliable integration of a large‐scale solar‐dependent plant through an appropriately sized battery energy storage system.
Ion-acoustic Gardner Solitons in electron-positron-ion plasma with two-electron temperature distributions
Authors: Rehman Momin A. , Mishra M. K.
Published: January 2016

The ion–acoustic solitons in collisionless plasma consisting of warm adiabatic ions, isothermal positrons, and two temperature distribution of electrons have been studied. Using reductive perturbation method, Korteweg-de Vries (K-dV), the modified K-dV (m-KdV), and Gardner equations are derived for the system. The soliton solution of the Gardner equation is discussed in detail. It is found that for a given set of parameter values, there exists a critical value of β=Tc/Th, (ratio of cold to hot electron temperature) below which only rarefactive KdV solitons exist and above it compressive KdV solitons exist. At the critical value of β, both compressive and rarefactive m-KdV solitons co-exist. We have also investigated the soliton in the parametric regime where the KdV equation is not valid to study soliton solution. In this region, it is found that below the critical concentration the system supports rarefactive Gardner solitons and above it compressive Gardner solitons are found. The effects of temperature ratio of two-electron species, cold electron concentration, positron concentration on the characteristics of solitons are also discussed.
A gasdynamic gun driven by gaseous detonation
Authors: Li Jinping , Chen Hong , Zhang Shizhong , Zhang Xiaoyuan , Yu Hongru
Published: January 2016

A gasdynamic gun driven by gaseous detonation was developed to address the disadvantages of the insufficient driving capability of high-pressure gas and the constraints of gunpowder. The performance of this gasdynamic gun was investigated through experiments and numerical simulations. Much more powerful launching capability was achieved by this gun relative to a conventional high-pressure gas gun, owing to the use of the chemical energy of the driver gas. To achieve the same launching condition, the initial pressure required for this gun was an order of magnitude lower than that for a gun driven by high-pressure H2. Because of the presence of the detonation, however, a more complex internal ballistic process of this gun was observed. Acceleration of projectiles for this gun was accompanied by a series of impulse loads, in contrast with the smooth acceleration for a conventional one, which indicates that this gun should be used conditionally. The practical feasibility of this gun was verified by experiments. The experiments demonstrated the convenience of taking advantage of the techniques developed for detonation-driven shock tubes and tunnels.
Symmetric deformed binomial distributions: An analytical example where the Boltzmann-Gibbs entropy is not extensive
Authors: Bergeron H. , Curado E. M. F. , Gazeau J. P. , Rodrigues Ligia M. C. S.
Published: January 2016

Asymptotic behavior (with respect to the number of trials) of symmetric generalizations of binomial distributions and their related entropies is studied through three examples. The first one has the q-exponential as the generating function, the second one involves the modified Abel polynomials, and the third one has Hermite polynomials. We prove analytically that the Rényi entropy is extensive for these three cases, i.e., it is proportional (asymptotically) to the number n of events and that q-exponential and Hermite cases have also extensive Boltzmann-Gibbs. The Abel case is exceptional in the sense that its Boltzmann-Gibbs entropy is not extensive and behaves asymptotically as the square root of n. This result is obtained numerically and also confirmed analytically, under reasonable assumptions, by using a regularization of the beta function and its derivative. Probabilistic urn and genetic models are presented for illustrating this remarkable case.
High transmission acoustic focusing by impedance-matched acoustic meta-surfaces
Authors: Al Jahdali Rasha , Wu Ying
Published: January 2016

Impedance is an important issue in the design of acoustic lenses because mismatched impedance is detrimental to real focusing applications. Here, we report two designs of acoustic lenses that focus acoustic waves in water and air, respectively. They are tailored by acoustic meta-surfaces, which are rigid thin plates decorated with periodically distributed sub-wavelength slits. Their respective building blocks are constructed from the coiling-up spaces in water and the layered structures in air. Analytic analysis based on coupled-mode theory and transfer matrix reveals that the impedances of the lenses are matched to those of the background media. With these impedance-matched acoustic lenses, we demonstrate the acoustic focusing effect by finite-element simulations.
Wide-angle, polarization-independent ultrathin broadband visible absorbers
Authors: Lee Kyu-Tae , Ji Chengang , Guo L. Jay
Published: January 2016

A capability of absorbing a broad range of visible lights is essential to boost the performance of various applications, such as photovoltaics (PV), photodetectors, and thermal emitters. Here, we present an angle-insensitive, polarization-independent ultrathin (<150 nm) broadband absorber in the visible regime exploiting strong interference behaviors in highly absorbing semiconductor materials. A proposed structure simply has four layers composed of two stacks of a metal and a semiconductor demonstrating a remarkably enhanced absorption property as compared with the device without a top semiconductor film. This is attributed to multi-cavity resonance effects in each cavity, which is obviously elucidated with phase calculations and electric field distributions. The maximum absorption efficiency of the device is 95.5% at a resonance and its absorption characteristic can be maintained over a wide angle of incidence up to ±70° regardless of the incident light polarization. Finally, we investigate how our approach can be utilized to achieve a tandem PV cell with high efficiency. Our strategy can be applied to other material systems and can be useful in diverse applications, including thermal emitters and PV.
Electronic properties of freestanding Ti3C2Tx MXene monolayers
Authors: Miranda A. , Halim J. , Barsoum M. W. , Lorke A.
Published: January 2016

We report on the electrical characterization of single MXene Ti3C2Tx flakes (where T is a surface termination) and demonstrate the metallic nature of their conductivities. We also show that the carrier density can be modulated by an external gate voltage. The density of free carriers is estimated to be 8 ± 3 × 1021 cm−3 while their mobility is estimated to be 0.7 ± 0.2 cm2/V s. Electrical measurements, in the presence of a magnetic field, show a small, but clearly discernable, quadratic increase in conductance at 2.5 K.
Strain profiles in ion implanted ceramic polycrystals: An approach based on reciprocal-space crystal selection
Authors: Palancher H. , Goudeau P. , Boulle A. , Rieutord F. , Favre-Nicolin V. , Blanc N. , Martin G. , Fouet J. , Onofri C.
Published: January 2016

The determination of the state of strain in implanted materials is a key issue in the study of their mechanical stability. Whereas this question is nowadays relatively easily solved in the case of single crystals, it remains a challenging task in the case of polycrystalline materials. In this paper, we take benefit of the intense and parallel beams provided by third generation synchrotron sources combined with a two-dimensional detection system to analyze individual grains in polycrystals, hence obtaining “single crystal-like” data. The feasibility of the approach is demonstrated with implanted UO2 polycrystals where the in-depth strain profile is extracted for individual grains using numerical simulations of the diffracted signal. The influence of the implantation dose is precisely analyzed for several diffracting planes and grains. This work suggests that, at low fluences, the development of strain is mainly due to ballistic effects with little effect from He ions, independently from the crystallographic orientation. At higher fluences, the evolution of the strain profiles suggests a partial and anisotropic plastic relaxation. With the present approach, robust and reliable structural information can be obtained, even from complex polycrystalline ceramic materials.
Effect of the size of nanoparticles on their dissolution within metal-glass nanocomposites under sustained irradiation
Authors: Vu T. H. Y. , Ramjauny Y. , Rizza G. , Hayoun M.
Published: January 2016

We investigate the dissolution law of metallic nanoparticles (NPs) under sustained irradiation. The system is composed of isolated spherical gold NPs (4–100 nm) embedded in an amorphous silica host matrix. Samples are irradiated at room temperature in the nuclear stopping power regime with 4 MeV Au ions for fluences up to 8 × 1016 cm−2. Experimentally, the dependence of the dissolution kinetics on the irradiation fluence is linear for large NPs (45–100 nm) and exponential for small NPs (4–25 nm). A lattice-based kinetic Monte Carlo (KMC) code, which includes atomic diffusion and ballistic displacement events, is used to simulate the dynamical competition between irradiation effects and thermal healing. The KMC simulations allow for a qualitative description of the NP dissolution in two main stages, in good agreement with the experiment. Moreover, the perfect correlation obtained between the evolution of the simulated flux of ejected atoms and the dissolution rate in two stages implies that there exists an effect of the size of NPs on their dissolution and a critical size for the transition between the two stages. The Frost-Russell model providing an analytical solution for the dissolution rate, accounts well for the first dissolution stage but fails in reproducing the data for the second stage. An improved model obtained by including a size-dependent recoil generation rate permits fully describing the dissolution for any NP size. This proves, in particular, that the size effect on the generation rate is the principal reason for the existence of two regimes. Finally, our results also demonstrate that it is justified to use a unidirectional approximation to describe the dissolution of the NP under irradiation, because the solute concentration is particularly low in metal-glass nanocomposites.
Post calibration of the two-dimensional electron cyclotron emission imaging instrument with electron temperature characteristics of the magnetohydrodynamic instabilities
Authors: Choi M. J. , Park H. K. , Yun G. S. , Nam Y. B. , Choe G. H. , Lee W. , Jardin S.
Published: January 2016

The electron cyclotron emission imaging (ECEI) instrument is widely used to study the local electron temperature (Te) fluctuations by measuring the ECE intensity IECE ∝ Te in tokamak plasmas. The ECEI measurement is often processed in a normalized fluctuation quantity against the time averaged value due to complication in absolute calibration. In this paper, the ECEI channels are relatively calibrated using the flat Te assumption of the sawtooth crash or the tearing mode island and a proper extrapolation. The 2-D relatively calibrated electron temperature (Te,rel) images are reconstructed and the displacement amplitude of the magnetohydrodynamic modes can be measured for the accurate quantitative growth analysis.
First passage times in homogeneous nucleation: Dependence on the total number of particles
Authors: Yvinec Romain , Bernard Samuel , Hingant Erwan , Pujo-Menjouet Laurent
Published: January 2016

Motivated by nucleation and molecular aggregation in physical, chemical, and biological settings, we present an extension to a thorough analysis of the stochastic self-assembly of a fixed number of identical particles in a finite volume. We study the statistics of times required for maximal clusters to be completed, starting from a pure-monomeric particle configuration. For finite volumes, we extend previous analytical approaches to the case of arbitrary size-dependent aggregation and fragmentation kinetic rates. For larger volumes, we develop a scaling framework to study the first assembly time behavior as a function of the total quantity of particles. We find that the mean time to first completion of a maximum-sized cluster may have a surprisingly weak dependence on the total number of particles. We highlight how higher statistics (variance, distribution) of the first passage time may nevertheless help to infer key parameters, such as the size of the maximum cluster. Finally, we present a framework to quantify formation of macroscopic sized clusters, which are (asymptotically) very unlikely and occur as a large deviation phenomenon from the mean-field limit. We argue that this framework is suitable to describe phase transition phenomena, as inherent infrequent stochastic processes, in contrast to classical nucleation theory.
A non-volatile four-state magnetic memory in a Co/(011)Pb(Mg1/3Nb2/3)O3-PbTiO3 heterostructure
Authors: Jiang Changjun , Wang Fenglong , Dong Chunhui , Zhou Cai , Wu Lei , Xue Desheng
Published: January 2016

A non-volatile four-state magnetic memory is achieved in a Co/(011)Pb(Mg1/3Nb2/3)O3-PbTiO3 heterostructure. The in-plane magnetization of ferromagnetic Co film in the heterostructure can be controlled both electrically and magnetically. Electric field mediated magnetism is caused by piezostrain effect, which displays a stable non-volatile remnant magnetization vs electric field looplike behavior. In-plane strain-electric field (S-E) behavior under different temperatures reveals a non-volatile strain switching effect, which is responsible for the non-volatile remnant magnetization switching through piezostrain mediated magnetoelectric effect. Further investigations on temperature dependence of S-E behavior suggest that the absent of the second non-180° domain switching may be responsible for the asymmetry in strain curves that causes the non-volatile strain switching, and therefore causes the non-volatile remanent magnetization switching, which is crucial for the four-state magnetoelectric memory.
Demonstration of a high repetition rate capillary discharge waveguide
Authors: Gonsalves A. J. , Liu F. , Bobrova N. A. , Sasorov P. V. , Pieronek C. , Daniels J. , Antipov S. , Butler J. E. , Bulanov S. S. , Waldron W. L. , Mittelberger D. E. , Leemans W. P.
Published: January 2016

A hydrogen-filled capillary discharge waveguide operating at kHz repetition rates is presented for parameters relevant to laser plasma acceleration (LPA). The discharge current pulse was optimized for erosion mitigation with laser guiding experiments and MHD simulation. Heat flow simulations and measurements showed modest temperature rise at the capillary wall due to the average heat load at kHz repetition rates with water-cooled capillaries, which is promising for applications of LPAs such as high average power radiation sources.
Explicit vector spherical harmonics on the 3-sphere
Authors: Ben Achour J. , Huguet E. , Queva J. , Renaud J.
Published: January 2016

We build a family of explicit one-forms on S3 which are shown to form a new complete set of eigenmodes for the Laplace-de Rham operator.
Near-ultraviolet micro-Raman study of diamond grown on GaN
Authors: Nazari M. , Hancock B. L. , Anderson J. , Savage A. , Piner E. L. , Graham S. , Faili F. , Oh S. , Francis D. , Twitchen D. , Holtz M.
Published: January 2016

Ultraviolet (UV) micro-Raman measurements are reported of diamond grown on GaN using chemical vapor deposition. UV excitation permits simultaneous investigation of the diamond (D) and disordered carbon (DC) comprising the polycrystalline layer. From line scans of a cross-section along the diamond growth direction, the DC component of the diamond layer is found to be highest near the GaN-on-diamond interface and diminish with characteristic length scale of ∼3.5 μm. Transmission electron microscopy (TEM) of the diamond near the interface confirms the presence of DC. Combined micro-Raman and TEM are used to develop an optical method for estimating the DC volume fraction.
Study of self-compliance behaviors and internal filament characteristics in intrinsic SiOx-based resistive switching memory
Authors: Chang Yao-Feng , Fowler Burt , Zhou Fei , Chen Ying-Chen , Lee Jack C.
Published: January 2016

Self-compliance characteristics and reliability optimization are investigated in intrinsic unipolar silicon oxide (SiOx)-based resistive switching (RS) memory using TiW/SiOx/TiW device structures. The program window (difference between SET voltage and RESET voltage) is dependent on external series resistance, demonstrating that the SET process is due to a voltage-triggered mechanism. The program window has been optimized for program/erase disturbance immunity and reliability for circuit-level applications. The SET and RESET transitions have also been characterized using a dynamic conductivity method, which distinguishes the self-compliance behavior due to an internal series resistance effect (filament) in SiOx-based RS memory. By using a conceptual “filament/resistive gap (GAP)” model of the conductive filament and a proton exchange model with appropriate assumptions, the internal filament resistance and GAP resistance can be estimated for high- and low-resistance states (HRS and LRS), and are found to be independent of external series resistance. Our experimental results not only provide insights into potential reliability issues but also help to clarify the switching mechanisms and device operating characteristics of SiOx-based RS memory.
Passive microrheology of soft materials with atomic force microscopy: A wavelet-based spectral analysis
Authors: Martinez-Torres C. , Arneodo A. , Streppa L. , Argoul P. , Argoul F.
Published: January 2016

Compared to active microrheology where a known force or modulation is periodically imposed to a soft material, passive microrheology relies on the spectral analysis of the spontaneous motion of tracers inherent or external to the material. Passive microrheology studies of soft or living materials with atomic force microscopy (AFM) cantilever tips are rather rare because, in the spectral densities, the rheological response of the materials is hardly distinguishable from other sources of random or periodic perturbations. To circumvent this difficulty, we propose here a wavelet-based decomposition of AFM cantilever tip fluctuations and we show that when applying this multi-scale method to soft polymer layers and to living myoblasts, the structural damping exponents of these soft materials can be retrieved.
Reconstructing three-dimensional reentrant cardiac electrical wave dynamics using data assimilation
Authors: Hoffman M. J. , LaVigne N. S. , Scorse S. T. , Fenton F. H. , Cherry E. M.
Published: January 2016

For many years, reentrant scroll waves have been predicted and studied as an underlying mechanism for cardiac arrhythmias using numerical techniques, and high-resolution mapping studies using fluorescence recordings from the surfaces of cardiac tissue preparations have confirmed the presence of visible spiral waves. However, assessing the three-dimensional dynamics of these reentrant waves using experimental techniques has been limited to verifying stable scroll-wave dynamics in relatively thin preparations. We propose a different approach to recovering the three-dimensional dynamics of reentrant waves in the heart. By applying techniques commonly used in weather forecasting, we combine dual-surface observations from a particular experiment with predictions from a numerical model to reconstruct the full three-dimensional time series of the experiment. Here, we use model-generated surrogate observations from a numerical experiment to evaluate the performance of the ensemble Kalman filter in reconstructing such time series for a discordant alternans state in one spatial dimension and for scroll waves in three dimensions. We show that our approach is able to recover time series of both observed and unobserved variables matching the truth. Where nearby observations are available, the error is reduced below the synthetic observation error, with a smaller reduction with increased distance from observations. Our findings demonstrate that state reconstruction for spatiotemporally complex cardiac electrical dynamics is possible and will lead naturally to applications using real experimental data.
An amorphous titanium dioxide metal insulator metal selector device for resistive random access memory crossbar arrays with tunable voltage margin
Authors: Cortese Simone , Khiat Ali , Carta Daniela , Light Mark E. , Prodromakis Themistoklis
Published: January 2016

Resistive random access memory (ReRAM) crossbar arrays have become one of the most promising candidates for next-generation non volatile memories. To become a mature technology, the sneak path current issue must be solved without compromising all the advantages that crossbars offer in terms of electrical performances and fabrication complexity. Here, we present a highly integrable access device based on nickel and sub-stoichiometric amorphous titanium dioxide (TiO2−x), in a metal insulator metal crossbar structure. The high voltage margin of 3 V, amongst the highest reported for monolayer selector devices, and the good current density of 104 A/cm2 make it suitable to sustain ReRAM read and write operations, effectively tackling sneak currents in crossbars without compromising fabrication complexity in a 1 Selector 1 Resistor (1S1R) architecture. Furthermore, the voltage margin is found to be tunable by an annealing step without affecting the device's characteristics.
Cooperative effect of oxygen-vacancy-rich layer and ferroelectric polarization on photovoltaic properties in BiFeO3 thin film capacitors
Authors: Matsuo Hiroki , Kitanaka Yuuki , Inoue Ryotaro , Noguchi Yuji , Miyayama Masaru
Published: January 2016

Photovoltaic (PV) properties of ferroelectric SrRuO3/BiFeO3/SrRuO3 (SRO/BFO/SRO) epitaxial thin-film capacitors are investigated. The experimental results of the markedly reduced PV response caused by the doping of Mn provide evidence that the PV properties originate not from the bulk-derived PV effect but from an interfacial band bending. We show that the capacitors having a defective layer composed of oxygen vacancies at the SRO/BFO interface exhibit a markedly large photocurrent. Our study demonstrates that a cooperative effect between the interface charges arising from ferroelectric polarization and the oxygen-vacancy-rich layer enhances the PV response in capacitor form in the BFO system.
Room temperature sputtering of inclined c-axis ZnO for shear mode solidly mounted resonators
Authors: Rughoobur G. , DeMiguel-Ramos M. , Mirea T. , Clement M. , Olivares J. , Díaz-Durán B. , Sangrador J. , Miele I. , Milne W. I. , Iborra E. , Flewitt A. J.
Published: January 2016

ZnO films with a c-axis significantly inclined away from the surface normal were grown by a remote plasma sputtering technique at room temperature. The films were used to make solidly mounted resonators (SMRs) operating in shear mode at a resonant frequency of 1.35 GHz. Control of the ZnO microstructure was achieved using a polycrystalline AlN seed layer which can be added on top of a sputtered acoustic mirror to give a complete SMR device. The ZnO was reactively sputtered in an atmosphere of argon and oxygen from a zinc target. The c-axis of the ZnO was estimated to be at an angle of ∼45° to the surface normal. SMRs were measured to have quality factors (Q) of up to 140 and effective electromechanical coupling coefficients of up to 2.2% in air. Although an inclined c-axis can be achieved with direct growth onto the acoustic mirror, it is shown that the AlN seed layer provides higher coupling coefficients and narrower inclination angular distribution. The responses of the devices in liquids of different viscosities (acetone, water, and AZ5214E photoresist) were measured. The shear mode Q decreased by 45% in acetone, 72% in water, and 92% in AZ5214E.
Reversible transition between bipolar and unipolar resistive switching in Cu2O/Ga2O3 binary oxide stacked layer
Authors: Zhi Y. S. , Li P. G. , Wang P. C. , Guo D. Y. , An Y. H. , Wu Z. P. , Chu X. L. , Shen J. Q. , Tang W. H. , Li C. R.
Published: January 2016

Both unipolar resistive switching (URS) and bipolar resistive switching (BRS) behaviors are observed in Cu2O/Ga2O3 stacked layer. The conversion between BRS and URS is controllable and reversible. The switching operations in BRS mode requires smaller voltage than that in the URS mode. The oxygen vacancies closed to the Cu2O/Ga2O3 interface contributes to the BRS, and the bias-controlling filament formation/rupture in depletion layer is considered to contribute to the URS. The URS happens only in the negative voltage part due to the nature of directionality of the p-n junction. The process reported here can be developed to design memory device.
Microstructure and mechanical properties of equal channel angular pressed Mg–Y–RE–Zr alloy
Authors: Zhou L. , Liu Y. , Zhang J. , Kang Z.
Published: January 2016

The microstructure and mechanical properties of equal channel angular pressed (ECAP) Mg–Y–RE–Zr alloy (WE43) are examined. Results show that after ECAP, the average grain size remarkably decreases from ∼50 µm at initial state to ∼1.5 µm through ECAP for four passes and the homogeneity of microstructure also improves gradually. Meanwhile the secondary-phase β-Mg5RE morphology has obvious transformation from plate-like to spherical. Moreover, the initial random texture is converted to the strong (0002) basal texture. The ultimate tensile strength and yield strength increase in all passes. However, the ductility exhibits a tendency of increase from 1 to 4 passes then decrease from 4 to 12 passes. The variation in strength and ductility is attributed to the effect of specific microstructure evolution.
Mechanical anisotropy in Ca-treated and ultra-low sulphur HSLA-100 steel
Authors: Abyazi A. , Ebrahimi A. R.
Published: January 2016

A few elongated MnS inclusions were observed in ultra-low sulphur HSLA-100 steel which significantly decreased the yield strength (YS), ultimate tensile strength and notch toughness of short transverse direction. The slight anisotropies of YS (≈5 MPa) and notch toughness (≈15 J) between longitudinal and transverse directions are correlated to the presence of texture components in the vicinity of {113}<110> and {554}<225>. In the case of anisotropy between longitudinal and short transverse directions, it is found that recognising the contribution of each effective factor in the creation of strength anisotropy is not possible. However, the most primary effective factor in the creation of remarkable notch toughness anisotropy (≈70 Pct), especially at −85°C, is related to the existence of elongated MnS inclusions.