bluuebunny/crossref_metadata_2025 huggingface dataset:
Geometrical tradeoffs in graphene-based deeply-scaled electrically reconfigurable metasurfaces
Authors: Arezoomandan Sara , Sensale-Rodriguez Berardi
Published: March 2015

In this work we study the terahertz light propagation through deeply-scaled graphene-based reconfigurable metasurfaces, i.e. metasurfaces with unit-cell dimensions much smaller than the terahertz wavelength. These metasurfaces are analyzed as phase modulators for constructing reconfigurable phase gradients along an optical interface for the purpose of beam shaping. Two types of deeply-scaled metacell geometries are analyzed and compared, which consist of: (i) multi split ring resonators and (ii) multi spiral resonators. Two figures of merit, related to: (a) the loss and (b) the degree of reconfigurability achievable by such metamaterials -when applied in beam shaping applications-, are introduced and discussed. Simulations of these two types of deep-subwavelength geometries, when changing the metal coverage-fraction, show that there is an optimal coverage-fraction that gives the best tradeoff in terms of loss versus degree of reconfigurability. For both types of geometries the best tradeoff occurs when the area covered by the metallic region is around 40% of the metacell total area. From this point of view, reconfigurable deeply-scaled metamaterials can indeed provide a superior performance for beam shaping applications when compared to not deeply-scaled ones; however, counterintuitively, employing very highly-packed structures might not be beneficial for such applications.
Statistical Thermodynamics of Irreversible Aggregation: The Sol-Gel Transition
Authors: Matsoukas Themis
Published: March 2015

Binary aggregation is known to lead, under certain kinetic rules, to the coexistence of two populations, one consisting of finite-size clusters (sol) and one that contains a single cluster that carries a finite fraction of the total mass (giant component or gel). The sol-gel transition is commonly discussed as a phase transition by qualitative analogy to vapor condensation. Here we show that the connection to thermodynamic phase transition is rigorous. We develop the statistical thermodynamics of irreversible binary aggregation in discrete finite systems, obtain the partition function for arbitrary kernel and show that the emergence of the gel cluster has all the hallmarks of a phase transition, including an unstable van der Waals loop. We demonstrate the theory by presenting the complete pre- and post-gel solution for aggregation with the product kernel.
Cascade exciton-pumping engines with manipulated speed and efficiency in light-harvesting porous π-network films
Authors: Gu Cheng , Huang Ning , Xu Fei , Gao Jia , Jiang Donglin
Published: March 2015

Light-harvesting antennae are the machinery for exciton pumping in natural photosynthesis, whereas cascade energy transfer through chlorophyll is key to long-distance, efficient energy transduction. Numerous artificial antennae have been developed. However, they are limited in their cascade energy-transfer abilities because of a lack of control over complex chromophore aggregation processes, which has impeded their advancement. Here we report a viable approach for addressing this issue by using a light-harvesting porous polymer film in which a three-dimensional π-network serves as the antenna and micropores segregate multiple dyes to prevent aggregation. Cascade energy-transfer engines are integrated into the films; the rate and efficiency of the energy-funneling engines are precisely manipulated by tailoring the dye components and contents. The nanofilms allow accurate and versatile luminescence engineering, resulting in the production of thirty emission hues, including blue, green, red and white. This advance may open new pathways for realising photosynthesis and photoenergy conversion.
Paramagnetic Nanoparticles as a Platform for FRET-Based Sarcosine Picomolar Detection
Authors: Heger Zbynek , Cernei Natalia , Krizkova Sona , Masarik Michal , Kopel Pavel , Hodek Petr , Zitka Ondrej , Adam Vojtech , Kizek Rene
Published: March 2015

Herein, we describe an ultrasensitive specific biosensing system for detection of sarcosine as a potential biomarker of prostate carcinoma based on Förster resonance energy transfer (FRET). The FRET biosensor employs anti-sarcosine antibodies immobilized on paramagnetic nanoparticles surface for specific antigen binding. Successful binding of sarcosine leads to assembly of a sandwich construct composed of anti-sarcosine antibodies keeping the Förster distance (Ro) of FRET pair in required proximity. The detection is based on spectral overlap between gold-functionalized green fluorescent protein and antibodies@quantum dots bioconjugate (λex400 nm). The saturation curve of sarcosine based on FRET efficiency (F604/F510ratio) was tested within linear dynamic range from 5 to 50 nM with detection limit down to 50 pM. Assembled biosensor was then successfully employed for sarcosine quantification in prostatic cell lines (PC3, 22Rv1, PNT1A) and urinary samples of prostate adenocarcinoma patients.
Visual Attention Model Based on Statistical Properties of Neuron Responses
Authors: Duan Haibin , Wang Xiaohua
Published: March 2015

Visual attention is a mechanism of the visual system that can select relevant objects from a specific scene. Interactions among neurons in multiple cortical areas are considered to be involved in attentional allocation. However, the characteristics of the encoded features and neuron responses in those attention related cortices are indefinite. Therefore, further investigations carried out in this study aim at demonstrating that unusual regions arousing more attention generally cause particular neuron responses. We suppose that visual saliency is obtained on the basis of neuron responses to contexts in natural scenes. A bottom-up visual attention model is proposed based on the self-information of neuron responses to test and verify the hypothesis. Four different color spaces are adopted and a novel entropy-based combination scheme is designed to make full use of color information. Valuable regions are highlighted while redundant backgrounds are suppressed in the saliency maps obtained by the proposed model. Comparative results reveal that the proposed model outperforms several state-of-the-art models. This study provides insights into the neuron responses based saliency detection and may underlie the neural mechanism of early visual cortices for bottom-up visual attention.
Origin of 1/f noise in hydration dynamics on lipid membrane surfaces
Authors: Yamamoto Eiji , Akimoto Takuma , Yasui Masato , Yasuoka Kenji
Published: March 2015

Water molecules on lipid membrane surfaces are known to contribute to membrane stability by connecting lipid molecules and acting as a water bridge. Although water structures and diffusivities near the membrane surfaces have been extensively studied, hydration dynamics on the surfaces has remained an open question. Here we investigate residence time statistics of water molecules on the surface of lipid membranes using all-atom molecular dynamics simulations. We show that hydration dynamics on the lipid membranes exhibits 1/f noise. Constructing a dichotomous process for the hydration dynamics, we find that residence times in each state follow a power-law with exponential cutoff and that the process can be regarded as a correlated renewal process where interoccurrence times are correlated. The results imply that the origin of the 1/f noise in hydration dynamics on the membrane surfaces is a combination of a power-law distribution with cutoff of interoccurrence times of switching events and a long-term correlation between the interoccurrence times. These results suggest that the 1/f noise attributed to the correlated renewal process may contribute to the stability of the hydration layers and lipid membranes.
Effects of N-glycosylation on protein conformation and dynamics: Protein Data Bank analysis and molecular dynamics simulation study
Authors: Lee Hui Sun , Qi Yifei , Im Wonpil
Published: March 2015

N-linked glycosylation is one of the most important, chemically complex and ubiquitous post-translational modifications in all eukaryotes. The N-glycans that are covalently linked to proteins are involved in numerous biological processes. There is considerable interest in developments of general approaches to predict the structural consequences of site-specific glycosylation and to understand how these effects can be exploited in protein design with advantageous properties. In this study, the impacts of N-glycans on protein structure and dynamics are systematically investigated using an integrated computational approach of the Protein Data Bank structure analysis and atomistic molecular dynamics simulations of glycosylated and deglycosylated proteins. Our study reveals that N-glycosylation does not induce significant changes in protein structure, but decreases protein dynamics, likely leading to an increase in protein stability. Overall, these results suggest not only a common role of glycosylation in proteins, but also a need for certain proteins to be properly glycosylated to gain their intrinsic dynamic properties.
Phase transitions in free water nanoparticles. Theoretical modeling of [H2O]48 and [H2O]118
Authors: Vítek Aleš , Kalus René
Published: March 2015

Classical parallel-tempering Monte Carlo simulations of [H2O]48 and [H2O]118 have been performed in the isothermal–isobaric ensemble and a two-dimensional multiple-histogram method has been used to calculate the heat capacity of the two clusters.
TiCl4-promoted condensation of methyl acetoacetate, isobutyraldehyde, and indole: a theoretical and experimental study
Authors: Renzetti Andrea , Marrone Alessandro , Gérard Stéphane , Sapi Janos , Nakazawa Hiroshi , Re Nazzareno , Fontana Antonella
Published: March 2015

A combined DFT and experimental study of the title reaction points to a three-step mechanism: (1) titanium enolate formation, (2) Knoevenagel condensation of enolate and aldehyde, and (3) Michael addition of indole.
Variability assessment of 15N metabolic labeling-based proteomics workflow in mouse plasma and brain
Authors: Filiou Michaela D. , Soukupova Magdalena , Rewerts Christiane , Webhofer Christian , Turck Chris W. , Maccarrone Giuseppina
Published: March 2015

Repeatability of the 15N metabolic labeling workflow for quantitative proteomics in mouse plasma and brain specimens.
The enhanced photoactivity of hydrogenated TiO2@reduced graphene oxide with p–n junctions
Authors: Zhang Xiaoying , Chen Zhuoyuan
Published: March 2015

The preparation processes of hydrogenated TiO2@reduced graphene oxide composites with p–n heterojunctions.
Novel cross-linked anion exchange membrane based on hexaminium functionalized poly(vinylbenzyl chloride)
Authors: Vengatesan Singaram , Santhi Subramanyan , Sozhan Ganapathy , Ravichandran Subbiah , Davidson D. Jonas , Vasudevan Subramanyan
Published: March 2015

A novel cross-linked poly(vinylbenzyl chloride) anion exchange membrane is prepared using β-hydrogen free ‘hexamine’ as an amination agent.
Ligand-, base-, co-catalyst-free copper fluorapatite (CuFAP) as a versatile, ecofriendly, heterogeneous and reusable catalyst for an efficient homocoupling of arylboronic acid at ambient reaction conditions
Authors: Mulla Shafeek A. R. , Chavan Santosh S. , Pathan Mohsinkhan Y. , Inamdar Suleman M. , Shaikh Taufeekaslam M. Y.
Published: March 2015

CuFAP acts as a ligand-, base-, co-catalyst-free, versatile, eco-friendly, recyclable, and heterogeneous catalyst for an efficient synthesis of symmetric biaryls in excellent yields.
Exceptionally long-lived light-emitting electrochemical cells: multiple intra-cation π-stacking interactions in [Ir(C^N)2(N^N)][PF6] emitters
Authors: Bünzli Andreas M. , Constable Edwin C. , Housecroft Catherine E. , Prescimone Alessandro , Zampese Jennifer A. , Longo Giulia , Gil-Escrig Lidón , Pertegás Antonio , Ortí Enrique , Bolink Henk J.
Published: March 2015

Extremely long-lived LEC devices have been achieved using [Ir(C^N)2(bpy)]+ complexes with phenyl-substituted C^N ligands.
Preparation of brookite titania quasi nanocubes and their application in dye-sensitized solar cells
Authors: Xu Jinlei , Li Kan , Wu Shufang , Shi Wenye , Peng Tianyou
Published: March 2015

Brookite TiO2 quasi-nanocubes were synthesized and used as an overlayer to fabricate bilayer TiO2 film-based DSSCs with enhanced efficiency.
Enhancing refractive index sensing capability with hybrid plasmonic–photonic absorbers
Authors: Liu Zhengqi , Yu Meidong , Huang Shan , Liu Xiaoshan , Wang Yan , Liu Mulin , Pan Pingping , Liu Guiqiang
Published: March 2015

A significantly enhanced refractive index sensor with a maximum figure of merit (FOM*) value of about 1337 has been demonstrated based on a hybrid plasmonic–photonic absorberviautilizing substantial absorption contrast between a perfect absorber (∼99% at normal incidence) and a non-perfect absorber when there are changes in the surrounding.
Theoretical analysis of ion conductance and gating transitions in the OpdK (OccK1) channel
Authors: Pothula Karunakar Reddy , Kleinekathöfer Ulrich
Published: March 2015

Molecular simulations have been performed on the pore OpdK elucidating molecular details of ion conductance and a possible gating mechanism.
A comparative study on sample preparation procedures for supplementary foods by ICP-OES: Green chemistry considerations
Authors: Ruiz-de-Cenzano Manuela , Rochina-Marco Arancha , Ruiz Jessica , Cervera M. Luisa , de la Guardia Miguel
Published: March 2015

An inductively coupled plasma optical emission (ICP-OES) method was developed for the simultaneous determination of major, minor and trace elements in food.
Ruthenium-catalyzed aerobic oxidative decarboxylation of amino acids: a green, zero-waste route to biobased nitriles
Authors: Claes Laurens , Verduyckt Jasper , Stassen Ivo , Lagrain Bert , De Vos Dirk E.
Published: March 2015

The oxidative decarboxylation of amino acids into biobased nitriles was performed using molecular oxygen and a supported ruthenium hydroxide-based catalyst. A range of amino acids was successfully oxidized in a salt-free aqueous system under mild conditions.
General CuBr2-catalyzed highly enantioselective approach for optically active allenols from terminal alkynols
Authors: Huang Xin , Cao Tao , Han Yulin , Jiang Xingguo , Lin Weilong , Zhang Jiasheng , Ma Shengming
Published: March 2015

A copper(ii) bromide-catalyzed highly enantioselective direct synthesis of 1,3-disubstituted allenols from commercially available aldehydes, terminal alkynols and (R)- or (S)-α,α-diphenylprolinol has been developed.
The performance and stability of the oxygen reduction reaction on Pt–M (M = Pd, Ag and Au) nanorods: an experimental and computational study
Authors: Liang Yu-Ting , Lin Syuan-Pei , Liu Chen-Wei , Chung Shu-Ru , Chen Tsan-Yao , Wang Jeng-Han , Wang Kuan-Wen
Published: March 2015

The ORR activity of Pt3M NRs is related to the oxophilicity (ΔEads) and their segregation energy when exposed to oxygen containing species (OCS*) determines their stability.
Single-crystal-to-single-crystal transformation of an anion exchangeable dynamic metal–organic framework
Authors: Manna Biplab , Desai Aamod V. , Kumar Naveen , Karmakar Avishek , Ghosh Sujit K.
Published: March 2015

A 3D cationic Metal–Organic Framework has been fabricated with a neutral N-donor ligand and Cd(ClO4)2 which shows guest triggered dynamic behaviour at room temperature. This structural dynamism has been demonstrated from the SCSC transformation experiment.
Zinc oxide as a defect-dominated material in thin films for photovoltaic applications – experimental determination of defect levels, quantification of composition, and construction of band diagram
Authors: Krzywiecki Maciej , Grządziel Lucyna , Sarfraz Adnan , Iqbal Danish , Szwajca Anna , Erbe Andreas
Published: March 2015

In the present work we determine the electronic structure and quantify composition of sol–gel synthesized oxygen-deficient ZnO thin layers.
Simulation of metal–organic framework self-assembly
Authors: Yoneya Makoto , Tsuzuki Seiji , Aoyagi Masaru
Published: March 2015

Spontaneous growth of metal–organic frameworks (MOFs) composed of metal ions and 4,4′-bipyridine ligands was successfully demonstrated by molecular dynamics simulations, starting from a random initial placement of the metals and the ligands.
Mechanistic aspects of the gas-phase coupling of thioanisole and chlorobenzene to dibenzothiophene catalyzed by atomic Ho+
Authors: Zhou Shaodong , Schlangen Maria , Schwarz Helmut
Published: March 2015

Gas-phase coupling of thioanisole and chlorobenzene employing bare holmium cation as catalyst.
Reactions of phenylacetylene with nickel POCOP-pincer hydride complexes resulting in different outcomes from their palladium analogues
Authors: Wilson Gleason L. O. , Abraha Medhanei , Krause Jeanette A. , Guan Hairong
Published: March 2015

Nickel POCOP-pincer hydride complexes react with phenylacetylene to afford alkenyl complexes whereas the palladium analogues give alkynyl complexes.
Aqueous phase selective detection of 2,4,6-trinitrophenol using a fluorescent metal–organic framework with a pendant recognition site
Authors: Nagarkar Sanjog S. , Desai Aamod V. , Samanta Partha , Ghosh Sujit K.
Published: March 2015

A metal–organic framework with a pendant Lewis basic recognition site was employed to achieve selective detection of the nitro explosive TNP in the aqueous phase.
The effect of central and planar chirality on the electrochemical and chiral sensing properties of ferrocenyl urea H-bonding receptors
Authors: Mulas Andrea , Willener Yasmine , Carr-Smith James , Joly Kevin M. , Male Louise , Moody Christopher J. , Horswell Sarah L. , Nguyen Huy V. , Tucker James H. R.
Published: March 2015

Ferrocenyl urea receptors containing planar and central chirality electrochemically sense carboxylate anions via formation of H-bonded complexes.
Poly(phenanthrenequinone) as a conductive binder for nano-sized silicon negative electrodes
Authors: Kim Sang-Mo , Kim Myeong Hak , Choi Sung Yeol , Lee Jae Gil , Jang Jihyun , Lee Jeong Beom , Ryu Ji Heon , Hwang Seung Sik , Park Jin-Hwan , Shin Kyusoon , Kim Young Gyu , Oh Seung M.
Published: March 2015

The n-doped poly(phenanthrenequinone) is electrically conductive to be successfully used as the binder for nano-silicon negative electrodes.
Correction: Biophotovoltaics: oxygenic photosynthetic organisms in the world of bioelectrochemical systems
Authors: McCormick Alistair J. , Bombelli Paolo , Bradley Robert W. , Thorne Rebecca , Wenzel Tobias , Howe Christopher J.
Published: March 2015

Correction for ‘Biophotovoltaics: oxygenic photosynthetic organisms in the world of bioelectrochemical systems’ by Alistair J. Mccormick et al., Energy Environ. Sci., 2015, DOI: 10.1039/c4ee03875d.
Synthesis of shape-controlled NiO–graphene nanocomposites with enhanced supercapacitive properties
Authors: Feng Xiaomiao , Zhou Jinhua , Wang Linlin , Li Yi , Huang Zhendong , Chen Shufen , Ma Yanwen , Wang Lianhui , Yan Xiaohong
Published: March 2015

The flowerlike and polyhedral NiO–graphene composites show high supercapacitive performances which were synthesized using a facile hydrothermal method.
Synthesis and structural study of some new phosphorus(v) hydrazide compounds: spectroscopic evidence and a theoretical approach
Authors: Gholivand Khodayar , Molaei Foroogh
Published: March 2015

New phosphorus(v) hydrazides based on methyl and t-butyl carbazates are reported. Experimental trends are elucidated using DFT calculations.
Targeting ferritin receptors for the selective delivery of imaging and therapeutic agents to breast cancer cells
Authors: Geninatti Crich S. , Cadenazzi M. , Lanzardo S. , Conti L. , Ruiu R. , Alberti D. , Cavallo F. , Cutrin J. C. , Aime S.
Published: March 2015

Horse Spleen Apoferritin has been exploited to deliver simultaneously therapeutic and imaging agents to breast cancer cells via the ferritin transporting route. The selective uptake has been investigated by MRI, and exploited for the simultaneous delivery of Curcumin, a compound with strong anti-neoplastic and anti-inflammatory action.
Three-dimensional hotspots in evaporating nanoparticle sols for ultrahigh Raman scattering: solid–liquid interface effects
Authors: Sun Yudie , Han Zhenzhen , Liu Honglin , He Shengnan , Yang Liangbao , Liu Jinhuai
Published: March 2015

Decreasing interface adsorbing and increasing capillary-force packing of nanoparticles in an evaporating Ag-sol droplet is responsible for much higher SERS enhancement.
Composition–property relationships in multifunctional hollow mesoporous carbon nanosystems for PH-responsive magnetic resonance imaging and on-demand drug release
Authors: Zhang Shengjian , Qian Xiaoqing , Zhang Linlin , Peng Weijun , Chen Yu
Published: March 2015

A multiple stimuli-responsive theranostic system for cancer has been successfully developed simply by optimizing the chemical compositions of inorganic nanoplatforms.
Efficient synthesis of Au99(SR)42 nanoclusters
Authors: Liu Chao , Lin Jizhi , Shi Yangwei , Li Gao
Published: March 2015

We report a new synthetic protocol of Au99(SPh)42 nanoclusters with good efficiency (∼15% yield based on HAuCl4), via a combination of the ligand-exchange and “size-focusing” processes.
Growth of a polarity controlled ZnO nanorod array on a glass/FTO substrate by chemical bath deposition
Authors: Rathore Neelam , Rao D. V. Sridhara , Sarkar Shaibal K.
Published: March 2015

We present a polarity controlled ZnO nanorod thin film deposition on a glass substrate by Chemical Bath Deposition (CBD).
Synthesis and adsorption property of hydrophilic–hydrophobic macroporous crosslinked poly(methyl acryloyl diethylenetriamine)/poly(divinylbenzene) (PMADETA/PDVB) interpenetrating polymer networks (IPNs)
Authors: Li Hebing , Fu Zhenyu , Yang Li , Yan Chong , Chen Limiao , Huang Jianhan , Liu You-Nian
Published: March 2015

A novel hydrophilic–hydrophobic PMADETA/PDVB IPNs possesses a large equilibrium adsorption capacity to salicylic acid.
High-yield and environment-minded fabrication of nanoporous anodic aluminum oxide templates
Authors: Hong Young Ki , Kim Bo Hyun , Kim Dong Il , Park Dong Hyuk , Joo Jinsoo
Published: March 2015

High-yield and environment-minded fabrication of nanoporous AAO templates through simultaneous multi-surface anodization and direct detachment by applying stair-like reverse biases.
An odorless thia-Michael addition using Bunte salts as thiol surrogates
Authors: Lin Ya-mei , Lu Guo-ping , Cai Chun , Yi Wen-bin
Published: March 2015

An efficient thia-Michael addition using odorless, easy to synthesis and handle Bunte salts as thiol surrogates is introduced.
Cross-linked protein crystals by glutaraldehyde and their applications
Authors: Yan Er-Kai , Cao Hui-Ling , Zhang Chen-Yan , Lu Qin-Qin , Ye Ya-Jing , He Jin , Huang Lin-Jun , Yin Da-Chuan
Published: March 2015

The mechanism of cross-linked protein crystals using glutaraldehyde, and their properties and applications are discussed in detail.
Valorization of cellulose and waste paper to graphene oxide quantum dots
Authors: Adolfsson Karin H. , Hassanzadeh Salman , Hakkarainen Minna
Published: March 2015

Valorization of cellulose and waste paper to value-added 2D graphene oxide quantum dots through 3D carbon nanosphere intermediates from microwave assisted hydrothermal degradation.
Discovery and characterization of functional modules and pathogenic genes associated with the risk of coronary artery disease
Authors: Nie Wennan , Lv Yana , Yan Leyu , Guan Tianbing , Li Qiang , Guo Xiaojuan , Liu Wenhu , Feng Mengpei , Xu Guang , Chen Xi , Lv Haitao
Published: March 2015

An integrated network biology approach for identifying disease risk functional modules and risk pathogenic genes for associated with CAD risk.
Controlled growth of hexagonal Zn2GeO4 nanorods on carbon fibers for photocatalytic oxidation of p-toluidine
Authors: Jiang Guohua , Tang Bolin , Chen Hua , Liu Yongkun , Li Lei , Huang Qin , Chen Wenxing
Published: March 2015

Hexagonal Zn2GeO4 nanorods grown on the surface of carbon fiber substrates have been prepared for photocatalytic oxidation of p-toluidine.
Efficient and convenient oxidation of aldehydes and ketones to carboxylic acids and esters with H2O2catalyzed by Co4HP2Mo15V3O62in ionic liquid [TEBSA][BF4]
Authors: Hu Yu-Lin , Li De-Jiang , Li Dong-Sheng
Published: March 2015

A simple, efficient, and eco-friendly procedure for the oxidation of aldehydes and ketones to carboxylic acids and esters with H2O2catalyzed by Co4HP2Mo15V3O62in ionic liquid [TEBSA][BF4] has been developed.
The effect of light and humidity on the stability of silver nanowire transparent electrodes
Authors: Jiu Jinting , Wang Jun , Sugahara Tohru , Nagao Shijio , Nogi Masaya , Koga Hirotaka , Suganuma Katsuaki , Hara Masanao , Nakazawa Eri , Uchida Hiroshi
Published: March 2015

The resistance of AgNW films generally increased with storage time.
Binary Mg–Fe oxide as a highly active and magnetically separable catalyst for the synthesis of ethyl methyl carbonate
Authors: Wang Peixue , Liu Shimin , Ma Xiangyuan , He Yude , Alshammari Ahmad S. , Deng Youquan
Published: March 2015

The synthesis of ethyl methyl carbonate (EMC) from dimethyl carbonate (DMC) and diethyl carbonate (DEC) over magnetic binary Mg–Fe oxides.
Synthesis, crystal structure and catalytic property of a new samarium compound derived from 5-(pyrazin-2-yl)tetrazole-2-acetic acid
Authors: Zou Jian-Hua , Chen Dian-Yu , Yang Gao-Wen , Li Qiao-Yun , Yang Jie , Shen Lei
Published: March 2015

[Sm(pztza)2(H2O)6]·pztza·3H2O have been prepared successfully. It shows excellent catalytic property for the polymerization of vinyl monomers.
High selective fluorescence imaging of cesium distribution in Arabidopsis using a bis(trihydroxyphenyl)-appended fluorescent probe with a turn-on system
Authors: Jung Sung Ho , Hyun Tae Kyung , Kim Jae-Yean , Jung Jong Hwa
Published: March 2015

The bis(trihydroxyphenyl)-appended ligand 1 was found to display dramatically enhanced fluorescence upon the addition of Cs+, but not with any other metal ions.
Design of high surface area poly(ionic liquid)s to convert carbon dioxide into ethylene carbonate
Authors: Dani Alessandro , Groppo Elena , Barolo Claudia , Vitillo Jenny G. , Bordiga Silvia
Published: March 2015

In situFTIR monitoring of the evolution of ethylene carbonate catalyzed by a designed high surface area poly(ionic liquid).
New mesoporous titanosilicate MCM-36 material synthesized by pillaring layered ERB-1 precursor
Authors: Jin Fang , Chang Chih-Cheng , Yang Ciao-Wei , Lee Jyh-Fu , Jang Ling-Yun , Cheng Soofin
Published: March 2015

New mesoporous Ti-containing MCM-36 materials prepared by pillaring borosilicate ERB-1 precursor with titanosilicate have significantly improved catalytic activities in cyclohexene epoxidation, in comparison with analogous materials prepared from MCM-22.
Investigation of the structure–property relationship of thiadiazoloquinoxaline-based copolymer semiconductors via molecular engineering
Authors: An Cunbin , Li Mengmeng , Marszalek Tomasz , Guo Xin , Pisula Wojciech , Baumgarten Martin
Published: March 2015

Six thiadiazoloquinoxaline (TQ) based copolymers (P1–P6) have been synthesized using Stille coupling reaction upon varying donor moieties, substitution positions and architectures of polymer side chains.
EuS–CdS and EuS–ZnS heterostructured nanocrystals constructed by Co-thermal decomposition of molecular precursors in the solution phase
Authors: Gong Xueyun , Liu Zhengqing , Yan Dong , Zhao Hongyang , Li Na , Zhang Xinyu , Du Yaping
Published: March 2015

The EuS–CdS heterostructured nanocrystals, which possess unique optical-magnetic properties, were synthesized by a co-thermal decomposition method.
High‐efficiency high step‐up PWM resonant converter
Authors: Cai Yaping , Xu Jianping , Chen Zhangyong , Zhou Xiang
Published: March 2015

A novel high‐efficiency high step‐up pulse‐width modulation (PWM) resonant converter is proposed. It achieves high‐voltage step‐up by connecting the outputs of the boost converter cell and the isolated single‐ended PWM resonant converter cell in series, and high efficiency by zero current switching for the diode on the secondary side of the transformer of the single‐ended PWM resonant converter cell. The boost converter cell in the proposed converter can not only step‐up voltage, but also absorbs the leakage inductor energy during the turn‐off interval of the power switch to improve power conversion efficiency. Experimental results of a 100 W 35 V/200 V prototype are presented to verify the analysis results of the proposed converter.
Improved analysis of greedy block coordinate descent under RIP
Authors: Li Haifeng , Ma Yingbin , Liu WenAn , Fu Yuli
Published: March 2015

A more relaxed condition means that fewer of measurements are needed to ensure the exact sparse recovery from the theoretical aspect. The sufficient condition for the greedy block coordinate descent (GBCD) algorithm is relaxed using the near‐orthogonality property. It is also shown that the GBCD algorithm fails when (1/(√K+1)≤δK+1<1).
Remained p‐GaN effect to turn‐off energy loss (Eoff) in p‐GaN gate power devices
Authors: Choi Hyun‐Sik
Published: March 2015

In p‐GaN gate AlGaN/GaN power devices, the p‐GaN etching process to define the gate region is critical to device performance. In some cases, the remained p‐GaN in the ungated region can exist as a result of under‐etching, and can act like a charge reservoir in the p‐GaN gate power device. In this reported work, the effect of this remained p‐GaN layer is investigated for the first time. The main effect of the thick remained p‐GaN on the ungated region is the increments of turn‐off energy loss (Eoff) in spite of the similar turn‐on energy loss (Eon). This is related to the hole trapping in the remained p‐GaN region which is observed by the change of turn‐off gate voltages.
Minimising biases in full configuration interaction quantum Monte Carlo
Authors: Vigor W. A. , Spencer J. S. , Bearpark M. J. , Thom A. J. W.
Published: March 2015

We show that Full Configuration Interaction Quantum Monte Carlo (FCIQMC) is a Markov chain in its present form. We construct the Markov matrix of FCIQMC for a two determinant system and hence compute the stationary distribution. These solutions are used to quantify the dependence of the population dynamics on the parameters defining the Markov chain. Despite the simplicity of a system with only two determinants, it still reveals a population control bias inherent to the FCIQMC algorithm. We investigate the effect of simulation parameters on the population control bias for the neon atom and suggest simulation setups to, in general, minimise the bias. We show a reweight ing scheme to remove the bias caused by population control commonly used in diffusion Monte Carlo [Umrigar et al., J. Chem. Phys. 99, 2865 (1993)] is effective and recommend its use as a post processing step.
Structural fluctuations and orientational glass of levoglucosan—High stability against ordering and absence of structural glass
Authors: Tombari Elpidio , Johari G. P.
Published: March 2015

To investigate whether a non-exponential relaxation always indicates 2-4 nm-size regions of dynamic heterogeneity, we studied the kinetic freezing and unfreezing of structural fluctuations involving the rotational modes in orientationally disordered crystal (ODIC) of levoglucosan by calorimetry. The heat capacity, Cp, of levoglucosan measured over the 203 K–463 K range shows that its low-temperature, orientationally ordered crystal (ORC) transforms to ODIC phase on heating, which then melts to a low viscosity liquid. On cooling, the melt transforms to the ODIC which then does not transform to the ORC. Instead, the ODIC supercools. Fluctuations resulting from hindered (random) rotations of levoglucosan molecules confined to the lattice sites and from their conformational changes become progressively slower on cooling and an orientational glass (O-G) forms showing the sigmoid shape decrease in Cp characteristic of structural arrest like that of a glass. On heating the O-G state, rotational fluctuations begin to contribute to Cp at To-g of 247.8 K and there is an overshoot in Cp and thermal hysteresis (characteristic of physical ageing) in the temperature range of 230–260 K. The non-exponential relaxation parameter, βcal, determined by fitting the Cp data to a non-exponential, nonlinear model for relaxation of a glass is 0.60, which is similar to βcal found for polymers, molecular liquids, and metal-alloy melts in which Brownian diffusion occurs. Such βcal < 1 are seen to indicate 2-4 nm-size dynamically heterogeneous domains in an ultraviscous liquid near the glass formation, but its value of 0.60 for ODIC levoglucosan, in which Brownian diffusion does not occur, would not indicate such domains. Despite the lack of Brownian diffusion, we discuss these findings in the potential energy landscape paradigm. Levoglucosan melt, which is believed to vitrify and to stabilize a protein’s disordered structure, did not supercool even at 200 K/min cooling rate. The findings have consequences for reports on the dielectric relaxation studies that indicated that levoglucosan melt supercools to form a structural glass of Tg of ∼245 K, and for computer simulation of its dynamics. Levoglucosan is the ninth ODIC that forms O-G. It does so more easily than the other eight.
Evidence of sublaminar drag naturally occurring in a curved pipe
Authors: Noorani A. , Schlatter P.
Published: March 2015

Steady and unsteady flows in a mildly curved pipe for a wide range of Reynolds numbers are examined with direct numerical simulation. It is shown that in a range of Reynolds numbers in the vicinity of Reb ≈ 3400, based on bulk velocity and pipe diameter, a marginally turbulent flow is established in which the friction drag naturally reduces below the laminar solution at the same Reynolds number. The obtained values for friction drag for the laminar and turbulent (sublaminar) flows turn out to be in excellent agreement with experimental measurements in the literature. Our results are also in agreement with Fukagata et al. [“On the lower bound of net driving power in controlled duct flows,” Phys. D 238, 1082 (2009)], as the lower bound of net power required to drive the flow, i.e., the pressure drop of the Stokes solution, is still lower than our marginally turbulent flow. A large-scale traveling structure that is thought to be responsible for that behaviour is identified in the instantaneous field. This mode could also be extracted using proper orthogonal decomposition. The effect of this mode is to redistribute the mean flow in the circular cross section which leads to lower gradients at the wall compared to the laminar flow.
N2 dissociation on W(110): An ab initio molecular dynamics study on the effect of phonons
Authors: Nattino Francesco , Costanzo Francesca , Kroes Geert-Jan
Published: March 2015

Accurately modeling the chemisorption dynamics of N2 on metal surfaces is of both practical and fundamental interest. The factors that may have hampered this achievement so far are the lack of an accurate density functional and the use of approximate methods to deal with surface phonons and non-adiabatic effects. In the current work, the dissociation of molecular nitrogen on W(110) has been studied using ab initio molecular dynamics (AIMD) calculations, simulating both surface temperature effects, such as lattice distortion, and surface motion effects, like recoil. The forces were calculated using density functional theory, and two density functionals were tested, namely, the Perdew-Burke-Ernzerhof (PBE) and the revised PBE (RPBE) functionals. The computed dissociation probability considerably differs from earlier static surface results, with AIMD predicting a much larger contribution of the indirect reaction channel, in which molecules dissociate after being temporally trapped in the proximity of the surface. Calculations suggest that the surface motion effects play a role here, since the energy transfer to the lattice does not allow molecules that have been trapped into potential wells close to the surface to find their way back to the gas phase. In comparison to experimental data, AIMD results overestimate the dissociation probability at the lowest energies investigated, where trapping dominates, suggesting a failure of both tested exchange-correlation functionals in describing the potential energy surface in the area sampled by trapped molecules.
Mode locking and island suppression by resonant magnetic perturbations in Rutherford regime
Authors: Huang Wenlong , Zhu Ping
Published: March 2015

We demonstrate in theory that tearing mode locking and magnetic island suppression by resonant magnetic perturbations (RMPs) can correspond to different states of a same dynamic system governed by the torque balance and the nonlinear island evolution in the Rutherford regime. In particular, mode locking corresponds to the exact steady state of this system. A new exact analytic solution has been obtained for such a steady state, which quantifies the dependence of the locked mode island width on RMP amplitude in different plasma regimes. Furthermore, two different branches of mode locking have been revealed with the new analytic solution and the branch with suppressed island width turns out to be unstable in general. On the other hand, the system also admits stable states of island suppression achieved through the RMP modulation of tearing mode rotational frequency. When the RMP amplitude is above a certain threshold, the island suppression is transient until the tearing mode eventually gets locked. When the RMP amplitude is below the mode locking threshold, the island can be suppressed in a steady state on time-average, along with transient oscillations in rotational frequency and island width due to the absence of mode locking.
Controlling the microwave characteristic of FeCoB-ZnO granular thin films deposited by obliquely sputtering
Authors: Liu Xiaohong , Zuo Yalu , Zhou Xueyun , Li Wenchun , Feng Liefeng , Yao Dongsheng
Published: March 2015

A series of FeCoB-ZnO soft magnetic granular films deposited at different oblique angles were prepared by magnetron sputtering system. A variable in-plane uniaxial magnetic anisotropy field from 27.6 Oe to 212 Oe and an adjustable ferromagnetic resonance frequency from 1.89 GHz to 5.3 GHz were obtained in the as-deposited films just by increasing the oblique angle from 15° to 56°. Frequency line-width and effective Gilbert damping factor were both insensitive to the different oblique angles (αeff decreased from 0.036 to 0.03 and Δf decreased from 1.49 to 1.27), which almost satisfied the requirement that fFMR could be tuned independently in a certain frequency range. Besides, the change of dynamic magnetic anisotropy field versus oblique angle was illustrated and analyzed quantitatively compared with the static magnetic anisotropy.
Influence of size distribution and field amplitude on specific loss power
Authors: Boskovic M. , Goya G. F. , Vranjes-Djuric S. , Jovic N. , Jancar B. , Antic B.
Published: March 2015

Herein we present the results of specific loss power (SLP) analysis of polydisperse water based ferrofluids, Fe3O4/PEG200 and Fe3O4/PEG6000, with average Fe3O4 particle size of 9 nm and 11 nm, respectively. Specific loss power was measured in alternating magnetic field of various amplitudes and at fixed frequency of 580.5 kHz. Maximum SLP values acquired were 195 W/g for Fe3O4/PEG200 and 60 W/g for Fe3O4/PEG6000 samples. The samples were labeled as superparamagnetic by magnetization measurements, but SLP field dependence showed deviation from the behavior predicted by the commonly employed linear response theory. The scope of this theory for both samples with wide particle size distribution is discussed. Deviation from the expected behavior is explained by referring to polydisperse nature of the samples and field dependent relaxation rates.
Analysis of reliable sub-ns spin-torque switching under transverse bias magnetic fields
Authors: d'Aquino M. , Perna S. , Serpico C. , Bertotti G. , Mayergoyz I. D.
Published: March 2015

The switching process of a magnetic spin-valve nanosystem subject to spin-polarized current pulses is considered. The dependence of the switching probability on the current pulse duration is investigated. The further application of a transverse field along the intermediate anisotropy axis of the particle is used to control the quasi-random relaxation of magnetization to the reversed magnetization state. The critical current amplitudes to realize the switching are determined by studying the phase portrait of the Landau-Lifshtz-Slonczewski dynamics. Macrospin numerical simulations are in good agreement with the theoretical prediction and demonstrate reliable switching even for very short (below 100 ps) current pulses.
Central role of electronic temperature for photoelectron charge and spin mobilities in p+-GaAs
Authors: Cadiz F. , Paget D. , Rowe A. C. H. , Peytavit E. , Arscott S.
Published: March 2015

The charge and spin mobilities of minority photoelectrons in p+-GaAs are determined by monitoring the effect of an electric field on the spatial profiles of the luminescence and of its polarization. By using electric fields to increase the photoelectron temperature Te without significantly changing the hole or lattice temperatures, the charge and spin mobilities are shown to be principally dependent on Te. For Te > 70 K, both the charge and spin mobilities vary as Te−1.3, while at lower temperatures this changes to an even more rapid Te−4.3 law. This finding suggests that current theoretical models based on degeneracy of majority carriers cannot fully explain the observed temperature dependence of minority carrier mobility.
Correlation of a generation-recombination center with a deep level trap in GaN
Authors: Nguyen X. S. , Lin K. , Zhang Z. , McSkimming B. , Arehart A. R. , Speck J. S. , Ringel S. A. , Fitzgerald E. A. , Chua S. J.
Published: March 2015

We report on the identification of a deep level trap centre which contributes to generation-recombination noise. A n-GaN epilayer, grown by MOCVD on sapphire, was measured by deep level transient spectroscopy (DLTS) and noise spectroscopy. DLTS found 3 well documented deep levels at Ec − 0.26 eV, Ec − 0.59 eV, and Ec − 0.71 eV. The noise spectroscopy identified a generation recombination centre at Ec − 0.65 ± 0.1 eV with a recombination lifetime of 65 μs at 300 K. This level is considered to be the same as the one at Ec − 0.59 eV measured from DLTS, as they have similar trap densities and capture cross section. This result shows that some deep levels contribute to noise generation in GaN materials.
Identification of FOXO targets that generate diverse features of the diapause phenotype in the mosquito
Culex pipiens
Authors: Sim Cheolho , Kang David S. , Kim Sungshil , Bai Xiaodong , Denlinger David L.
Published: March 2015

Significance

Diapause is an alternative developmental pathway exploited by insects and other invertebrates to survive inimical seasons. Like many insects that enter an adult diapause, the mosquito
Culex pipiens
responds to the short day lengths of autumn by feeding extensively on sugar, stockpiling huge fat reserves, halting reproduction, suppressing metabolism, boosting defense responses, and migrating to protected sites where it can safely bridge the winter months. In the experiments presented here, we propose that many of the diverse features of the diapause phenotype are the consequence of activating forkhead transcription factor (FOXO), a transcription factor downstream of insulin and juvenile hormone signaling. Our experimental results reveal how these upstream hormonal signaling pathways act through FOXO to generate the complex phenotype known as diapause.
Corrections and Elaborations: A One-Night Stand in Narrations of Ferdowsi's Rostam and Sohrāb
Authors: Seyed-Gohrab Asghar
Published: March 2015

The Tahmineh and Rostam episode, as presented in modern text-critical editions of Ferdowsi's Shahnameh, is compared vis-à-vis both the pre-modern scribal interventions in the manuscript tradition of the poem, as well as two oral presentations of the same episode by traditional storytellers (naqqālān), as preserved in their prompt-books (tumārs) and in recorded performances from the twentieth century. The mise-en-scène, the social circmstances, as well as the expansive nature of such oral performances, are described, and a translation of an oral version of the Rostam and Tahmineh episode is given. The narrative strategies employed to negotiate the intersection of new episodes or contemporary moralistic considerations with the written text of Ferdowsi's Shahnameh are then explored, analyzing the nature, motivations and functions of the scribal and oral interpolations to the Tahmineh episode, and demonstrating how modernizing reinterpretations impart a certain dynamism to the living Shāhnāmeh tradition. The naqqālān are shown to alter the Tahmineh episode to comply with the moral and religious values of their audiences, the requirements of extended narration cycles, and the horizon of expectation of the genre of epic. The article closes with a brief consideration of how moral and religious values apply differentially across various genres (heroic epic, romance, etc.), and how these differing horizons of expectation impact the reinterpretation of the narrative material.
Characterization of Avt1p as a vacuolar proton/amino acid antiporter in Saccharomyces cerevisiae
Authors: Tone Junichi , Yoshimura Ayumi , Manabe Kunio , Murao Nami , Sekito Takayuki , Kawano-Kawada Miyuki , Kakinuma Yoshimi
Published: March 2015

Several genes for vacuolar amino acid transport were reported in Saccharomyces cerevisiae, but have not well been investigated. We characterized AVT1, a member of the AVT vacuolar transporter family, which is reported to be involved in lifespan of yeast. ATP-dependent uptake of isoleucine and histidine by the vacuolar vesicles of an AVT exporter mutant was lost by introducing avt1∆ mutation. Uptake activity was inhibited by the V-ATPase inhibitor: concanamycin A and a protonophore. Isoleucine uptake was inhibited by various neutral amino acids and histidine, but not by γ-aminobutyric acid, glutamate, and aspartate. V-ATPase-dependent acidification of the vesicles was declined by the addition of isoleucine or histidine, depending upon Avt1p. Taken together with the data of the amino acid contents of vacuolar fractions in cells, the results suggested that Avt1p is a proton/amino acid antiporter important for vacuolar compartmentalization of various amino acids.
Tannin-degrading bacteria with cellulase activity isolated from the cecum of the Qinghai-Tibet plateau zokor (Myospalax baileyi)
Authors: Bobrov Anatoly , Kravchenko Vasiliy D. , Müller Günter C.
Published: March 2015

Tannins, which are polyphenols present in various plants, have anti-nutritional activity; however, their negative effects are mitigated by the presence of tannin-degrading microorganisms in the gastrointestinal tract of animals. This has never been investigated in the plateau zokor (Myospalax baileyi) – the predominant small herbivore in the alpine meadow ecosystem of Qinghai Province, China – which consumes tannin-rich herbaceous plants. Tannase activity in the feces of the plateau zokor increased from June to August corresponding to the increase in hydrolyzable tannin concentrations in plants during this period, and three tannin-degrading facultative anaerobic strains (designated as E1, E2, and E3) were isolated from the cecum of these animals. Sequencing of the 16S rDNA gene identified isolates of strain E1 as belonging to the genusEnterococcus, and E2 and E3 to the genusBacillus. All of the bacteria had cellulose-degrading capacity. This study provides the first evidence of symbiotic bacterial strains that degrade tannic acid and cellulose in the cecum of plateau zokor.