bluuebunny/crossref_metadata_2025 huggingface dataset:
Photoresponsive self-healing supramolecular hydrogels for light-induced release of DNA and doxorubicin
Authors: Pianowski Zbigniew L. , Karcher Johannes , Schneider Knut
Published: January 2016

Biopolymers and bioactive small molecules are released with light from hydrogels formed by an azobenzene-containing cyclic dipeptide PAP-DKP-Lys.
DNA-based control of protein activity
Authors: Engelen W. , Janssen B. M. G. , Merkx M.
Published: January 2016

This feature article discusses the development of generic strategies to dynamically control protein activityviaDNA-based triggers.
A study on the interactions of amino acids with nitrogen doped graphene; docking, MD simulation, and QM/MM studies
Authors: Ghadari Rahim
Published: January 2016

The binding properties of twenty amino acids with nitrogen-doped graphene structures were studied using docking, MD simulation, and QM/MM methods.
Layering effects on low frequency modes in n-layered MX2 transition metal dichalcogenides
Authors: Cammarata Antonio , Polcar Tomas
Published: January 2016

M–X pair cophonicity can be exploited to tune intralayer charge distribution and low-frequency vibrational modes, hence intrinsic friction.
Electron transport mechanism of bathocuproine exciton blocking layer in organic photovoltaics
Authors: Lee Jeihyun , Park Soohyung , Lee Younjoo , Kim Hyein , Shin Dongguen , Jeong Junkyeong , Jeong Kwangho , Cho Sang Wan , Lee Hyunbok , Yi Yeonjin
Published: January 2016

The true electron transport mechanism of a bathocuproine exciton blocking layer in organic photovoltaics is comprehensively investigated.
Au-Catalysed oxidative cyclisation
Authors: Zheng Zhitong , Wang Zhixun , Wang Youliang , Zhang Liming
Published: January 2016

This review discusses the two main strategies of oxidative gold catalysis and their applications in developing valuable synthetic transformations.
Catalytic deoxygenation on transition metal carbide catalysts
Authors: Sullivan Mark M. , Chen Cha-Jung , Bhan Aditya
Published: January 2016

We highlight the evolution and tunability of catalytic function of transition metal carbides under oxidative and reductive environments for selective deoxygenation reactions.
Integration of borylation of aryllithiums and Suzuki–Miyaura coupling using monolithic Pd catalyst
Authors: Nagaki A. , Hirose K. , Moriwaki Y. , Mitamura K. , Matsukawa K. , Ishizuka N. , Yoshida J.
Published: January 2016

Integration of the preparation of arylboronic esters and Suzuki–Miyaura coupling using monolithic Pd catalyst was successfully achieved.
Cobalt salophen complexes for light-driven water oxidation
Authors: Asraf Md. Ali , Younus Hussein A. , Ezugwu Chizoba I. , Mehta Akshay , Verpoort Francis
Published: January 2016

Earth-abundant molecular complexes have been found to be excellent catalysts for the light-driven water oxidation reaction.
Towards validation of the NanoDUFLOW nanoparticle fate model for the river Dommel, The Netherlands
Authors: Klein Jeroen J. M. de , Quik Joris T. K. , Bäuerlein Patrick S. , Koelmans Albert A.
Published: January 2016

It is generally acknowledged that fate models for engineered nanoparticles (ENPs) hardly can be validated, given present limitations in analytical methods available for ENPs.
Archaeal ammonium oxidation coupled with bacterial nitrite oxidation in a simulated drinking water premise plumbing system
Authors: Santillana Gem E. , Smith Heidi J. , Burr Mark , Camper Anne K.
Published: January 2016

Simulated copper and PVC premise plumbing reactors modeling chloramine decay were monitored for complete nitrification of 0.71 mg NH4-N L−1ammonium to nitrate with no nitrite detected.
A review of whole cell wall NMR by the direct-dissolution of biomass
Authors: Foston Marcus , Samuel Reichel , He Jian , Ragauskas Arthur J.
Published: January 2016

A facile and effective method of plant cell wall characterization by direct dissolution of biomass in deuterated solvent systems and by subsequent NMR analysis.
Photocatalytic conversion of CO2 over graphene-based composites: current status and future perspective
Authors: Yang Min-Quan , Xu Yi-Jun
Published: January 2016

A critical summary and an insight of recent advances in photocatalytic reduction of CO2 to produce solar fuels and chemicals over graphene-based photocatalysts have been presented, with the purpose of describing the current status and promoting further development in this area.
α-Hydroxyacids accelerate the Diels–Alder reaction of dibutyl vinylboronate with cyclopentadiene: experimental results and mechanistic insights
Authors: Grimblat N. , Sarotti A. M. , Pisano P. L. , Pellegrinet S. C.
Published: January 2016

Dibutyl vinylboronate reacts with cyclopentadiene under mild conditions in the presence of (S)-mandelic acid probably via an activated dioxaborolane intermediate.
Compartmentalized vs. non-compartmentalized translocations in metal porphyrin complexes
Authors: Le Gac Stéphane , Boitrel Bernard
Published: January 2016

Strapped porphyrin ligands exhibit instantaneous and easy-to-control formation of various bimetallic species featuring new coordination modes and dynamics.
New low viscous cholinium-based magnetic ionic liquids
Authors: Rosatella Andreia A. , Siopa Filipa , Frade Raquel F. M. , Afonso Carlos A. M.
Published: January 2016

This study describes the synthesis of cholinium-based magnetic ionic liquids that are liquid at room temperature and have low toxicity to human cells.
Tuneable graphene nanopores for single biomolecule detection
Authors: Al-Dirini Feras , Mohammed Mahmood A. , Hossain Md Sharafat , Hossain Faruque M. , Nirmalathas Ampalavanapillai , Skafidas Efstratios
Published: January 2016

The architecture of a tuneable graphene nanopore device (left) and the highly sensitive detection of the carboxyl group in a glycine zwitterion as it translocates through the pore (right).
Enhanced performance of macrophage-encapsulated nanoparticle albumin-bound-paclitaxel in hypo-perfused cancer lesions
Authors: Leonard Fransisca , Curtis Louis T. , Yesantharao Pooja , Tanei Tomonori , Alexander Jenolyn F. , Wu Min , Lowengrub John , Liu Xuewu , Ferrari Mauro , Yokoi Kenji , Frieboes Hermann B. , Godin Biana
Published: January 2016

The proposed experimental/computational approach could enable prediction of nanotherapeutics performance to treat hypovascularized metastatic cancer in the liver.
Enhancing the therapeutic effects of polyphenols with macromolecules
Authors: Oliver Susan , Vittorio Orazio , Cirillo Giuseppe , Boyer Cyrille
Published: January 2016

A review of key macromolecular systems employed to stabilise polyphenols, including direct polymerisation of polyphenol monomers and conjugation with macromolecules.
Polymer/zinc hybrid-flow battery using block copolymer micelles featuring a TEMPO corona as catholyte
Authors: Winsberg Jan , Muench Simon , Hagemann Tino , Morgenstern Sabine , Janoschka Tobias , Billing Mark , Schacher Felix H. , Hauffman Guillaume , Gohy Jean-François , Hoeppener Stephanie , Hager Martin D. , Schubert Ulrich S.
Published: January 2016

A poly(TEMPO methacrylate)-poly(styrene) block copolymer was utilised as catholyte in polymer/zinc hybrid flow batteries.
In vitro and in vivo study of a colon-targeting resin microcapsule loading a novel prodrug, 3,4,5-tributyryl shikimic acid
Authors: Dong Kai , Zeng Aiguo , Wang Maoling , Dong Yalin , Wang Ke , Guo Chenning , Yan Yan , Zhang Lu , Shi Xianpeng , Xing Jianfeng
Published: January 2016

Prodrugs synthesized by different drugs not only overcome the defects of the original drugs, but also significantly enhance their treatment effects.
Ascorbic acid-coated Fe3O4 nanoparticles as a novel heterogeneous catalyst of persulfate for improving the degradation of 2,4-dichlorophenol
Authors: Sun Chao , Zhou Rui , E Jianan , Sun Jiaqiang , Su Yu , Ren Hejun
Published: January 2016

Magnetic nanoscaled ascorbic acid/magnetite (H2A/Fe3O4) composite was prepared by oxidative polymerization and proposed as a novel heterogeneous catalyst of persulfate (PS) for improved degradation of 2,4-dichlorophenol (2,4-DCP).
Effect of multi-walled carbon nanotubes on the morphology evolution, conductivity and rheological behaviors of poly(methyl methacrylate)/poly(styrene-co-acrylonitrile) blends during isothermal annealing
Authors: Li Hui-hui , Zuo Min , Liu Ting , Chen Qi , Zhang Jifei , Zheng Qiang
Published: January 2016

MWNTs migrate and aggregate in SAN-rich phase to form the double percolated structure with thermal-induced phase separation of blend matrix.
Au nanoparticles fluorescence switch-mediated target recycling amplification strategy for sensitive nucleic acid detection
Authors: Wei Haiping , Wang Yan , Zhang Hong , Zhao Haiyan , Jiang Wei
Published: January 2016

A sensitive strategy based on Au nanoparticles fluorescence switch-mediated target recycling amplification for nucleic acid detection.
Electrochemical synthesis of luminescent ferrous fluorosilicate hexahydrate (FeSiF6·6H2O) nano-powders
Authors: Pastushenko A. , Lysenko V.
Published: January 2016

Electrochemical etching of metallurgical FeSi2/Si substrate produces ferrous fluorosilicate hexahydrate (FeSiF6·6H2O) nano-powder with strong and stable photoluminescence.
A facile one-step synthesis of fluorescent silicon quantum dots and their application for detecting Cu2+
Authors: Liao Bo , Wang Wu , Deng Xiaoting , He Benqiao , Zeng Wennan , Tang Zilong , Liu Qingquan
Published: January 2016

Fluorescent silicon quantum dots were synthesized by a facile one-step synthesis that involved etching silicon powder through a hydrothermal method. Without any surface modification, these silicon quantum dots could be used as a sensor to detect Cu2+.
Effects of doping and planar defects on the thermoelectric properties of InAs nanowires
Authors: Jeon Seong Gi , Park Dong Woo , Shin Ho Sun , Park Hyun Min , Choi Si Young , Lee Sang Jun , Yu Jin , Song Jae Yong
Published: January 2016

Undoped InAs and Si-doped InAs nanowires with stacking faults and twins were synthesized by catalyst-free molecular beam epitaxy and their thermoelectric enhancements due to planar defects were experimentally and theoretically demonstrated.
High-efficiency and low efficiency roll-off near-infrared fluorescent OLEDs through triplet fusion
Authors: Xue Jie , Li Chen , Xin Lijun , Duan Lian , Qiao Juan
Published: January 2016

High-efficiency and low efficiency roll-off near-infrared fluorescent OLEDs are realized through effective triplet fusion of a bipolar host doped with a special non-donor–accepter naphthoselenadiazole emitter.
Surface-induced phase transitions of wormlike chains in slit confinement
Authors: Ye Shiwei , Zhang Pingwen , Chen Jeff Z. Y.
Published: January 2016

As the overall density increases, a semiflexible polymer fluid confined in a slit displays three orientational states, stage by stage. The main-axis orientational distributions of different states near the surface have different characteristics.
Efficient polymer solar cells based on the synergy effect of a novel non-conjugated small-molecule electrolyte and polar solvent
Authors: Liu Zhiyang , Ouyang Xinhua , Peng Ruixiang , Bai Yongqi , Mi Dongbo , Jiang Weigang , Facchetti Antonio , Ge Ziyi
Published: January 2016

The power conversion efficiencies of polymer solar cells were largely improved by introducing a non-conjugated small-molecule electrolyte as a cathode interlayer.
Controlled aqueous synthesis of ultra-long copper nanowires for stretchable transparent conducting electrode
Authors: Hwang Chahwan , An Jihyun , Choi Byung Doo , Kim Kwanpyo , Jung Soon-Won , Baeg Kang-Jun , Kim Myung-Gil , Ok Kang Min , Hong Jongin
Published: January 2016

A stretchable transparent electrode was achieved with rationally-controlled ultra-long copper nanowires and low-temperature direct spray coating.
Benzobisoxazole cruciforms: a tunable, cross-conjugated platform for the generation of deep blue OLED materials
Authors: Chavez III Ramiro , Cai Min , Tlach Brian , Wheeler David L. , Kaudal Rajiv , Tsyrenova Ayuna , Tomlinson Aimée L. , Shinar Ruth , Shinar Joseph , Jeffries-EL Malika
Published: January 2016

A structure–property investigation of a series of cross-conjugated molecules shows that their performance is dependent on both the nature of the substituents and their conjugation axis.
Fuzzy observer and fuzzy controller design for a class of uncertain non‐linear systems
Authors: Shuli Guo , Lina Han , Xianjia Feng
Published: January 2016

In this study, a fuzzy state observer and a fuzzy controller are developed for a class of uncertain non‐linear systems, which are represented through a set assumptions of matrix inequalities. Many original investigations and results are obtained. First, by constructing a class of Lyapunov functions and the introduced matrix inequalities tools, the adaptive observer laws including new Ricatti equations, two differentiators and many solvability conditions about the obtained Ricatti equations are presented. Second, based on another class of Lyapunov functions and the same matrix inequalities tools, the proposed controllers are designed to guarantee the stability of the overall closed‐loop systems, and many solvability conditions on the proposed controllers are analysed too. Finally, numerical simulations on the single‐input single‐output magnetic levitation systems show the effectiveness of these approaches. The above work allows to provide further applications on the proposed observer and controller designs without resorting to universal fuzzy approximation.
On absence of bound states for weakly attractive δ′-interactions supported on non-closed curves in ℝ2
Authors: Jex Michal , Lotoreichik Vladimir
Published: January 2016

Let Λ ⊂ ℝ2 be a non-closed piecewise-C1 curve, which is either bounded with two free endpoints or unbounded with one free endpoint. Let u±|Λ ∈ L2(Λ) be the traces of a function u in the Sobolev space H1(ℝ2∖Λ) onto two faces of Λ. We prove that for a wide class of shapes of Λ the Schrödinger operator HωΛ with δ′-interaction supported on Λ of strength ω ∈ L∞(Λ; ℝ) associated with the quadratic form H1(R2∖Λ)∋u↦∫R2∇u2dx−∫Λωu+|Λ−u−|Λ2ds has no negative spectrum provided that ω is pointwise majorized by a strictly positive function explicitly expressed in terms of Λ. If, additionally, the domain ℝ2∖Λ is quasi-conical, we show that σ(HωΛ)=[0,+∞). For a bounded curve Λ in our class and non-varying interaction strength ω ∈ ℝ, we derive existence of a constant ω∗ > 0 such that σ(HωΛ)=[0,+∞) for all ω ∈ (−∞, ω∗]; informally speaking, bound states are absent in the weak coupling regime.
Heating system of pellet samples integrated with terahertz spectrometer
Authors: Sterczewski L. A. , Grzelczak M. P. , Plinski E. F.
Published: January 2016

This article describes automation of temperature-dependent terahertz spectroscopic experiments. The proposed dual-heater temperature controller based on a cascade proportional-integral-derivative algorithm provides smooth temperature changes in the polyethylene-based pharmaceutical pellet samples. The device has been integrated with a terahertz time-domain spectrometer. Thermodynamic experiments can now be performed without any probe inserted into the measured sample. Selected results of temperature-induced evolution in terahertz spectra are presented.
Broadband cross-polarization-based heteronuclear dipolar recoupling for structural and dynamic NMR studies of rigid and soft solids
Authors: Kharkov B. B. , Chizhik V. I. , Dvinskikh S. V.
Published: January 2016

Dipolar recoupling is an essential part of current solid-state NMR methodology for probing atomic-resolution structure and dynamics in solids and soft matter. Recently described magic-echo amplitude- and phase-modulated cross-polarization heteronuclear recoupling strategy aims at efficient and robust recoupling in the entire range of coupling constants both in rigid and highly dynamic molecules. In the present study, the properties of this recoupling technique are investigated by theoretical analysis, spin-dynamics simulation, and experimentally. The resonance conditions and the efficiency of suppressing the rf field errors are examined and compared to those for other recoupling sequences based on similar principles. The experimental data obtained in a variety of rigid and soft solids illustrate the scope of the method and corroborate the results of analytical and numerical calculations. The technique benefits from the dipolar resolution over a wider range of coupling constants compared to that in other state-of-the-art methods and thus is advantageous in studies of complex solids with a broad range of dynamic processes and molecular mobility degrees.
Orientation-dependent energy level alignment and film growth of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on HOPG
Authors: Lyu Lu , Niu Dongmei , Xie Haipeng , Cao Ningtong , Zhang Hong , Zhang Yuhe , Liu Peng , Gao Yongli
Published: January 2016

Combining ultraviolet photoemission spectroscopy, X-ray photoemission spectroscopy, atomic force microscopy, and X-ray diffraction measurements, we performed a systematic investigation on the correlation of energy level alignment, film growth, and molecular orientation of 2,7-diocty[1]benzothieno[3,2-b]benzothiophene (C8-BTBT) on highly oriented pyrolytic graphite. The molecules lie down in the first layer and then stand up from the second layer. The ionization potential shows a sharp decrease from the lying down region to the standing up region. When C8-BTBT molecules start standing up, unconventional energy level band-bending-like shifts are observed as the film thickness increases. These shifts are ascribed to gradual decreasing of the molecular tilt angle about the substrate normal with the increasing film thickness.
Dielectric properties of crystalline organic molecular films in the limit of zero overlap
Authors: D’Avino Gabriele , Vanzo Davide , Soos Zoltán G.
Published: January 2016

We present the calculation of the static dielectric susceptibility tensor and dipole field sums in thin molecular films in the well-defined limit of zero intermolecular overlap. Microelectrostatic and charge redistribution approaches are applied to study the evolution of dielectric properties from one to a few molecular layers in films of different conjugated molecules with organic electronics applications. Because of the conditional convergence of dipolar interactions, dipole fields depend on the shape of the sample and different values are found in the middle layer of a thick film and in the bulk. The shape dependence is eliminated when depolarization is taken into account, and the dielectric tensor of molecular films converges to the bulk limit within a few molecular layers. We quantify the magnitude of surface effects and interpret general trends among different systems in terms of molecular properties, such as shape, polarizability anisotropy, and supramolecular organization. A connection between atomistic models for molecular dielectrics and simpler theories for polarizable atomic lattices is also provided.
Aggregation dynamics of rigid polyelectrolytes
Authors: Tom Anvy Moly , Rajesh R. , Vemparala Satyavani
Published: January 2016

Similarly charged polyelectrolytes are known to attract each other and aggregate into bundles when the charge density of the polymers exceeds a critical value that depends on the valency of the counterions. The dynamics of aggregation of such rigid polyelectrolytes are studied using large scale molecular dynamics simulations. We find that the morphology of the aggregates depends on the value of the charge density of the polymers. For values close to the critical value, the shape of the aggregates is cylindrical with height equal to the length of a single polyelectrolyte chain. However, for larger values of charge, the linear extent of the aggregates increases as more and more polymers aggregate. In both the cases, we show that the number of aggregates decrease with time as power laws with exponents that are not numerically distinguishable from each other and are independent of charge density of the polymers, valency of the counterions, density, and length of the polyelectrolyte chain. We model the aggregation dynamics using the Smoluchowski coagulation equation with kernels determined from the molecular dynamics simulations and justify the numerically obtained value of the exponent. Our results suggest that once counterions condense, effective interactions between polyelectrolyte chains short-ranged and the aggregation of polyelectrolytes are diffusion-limited.
Inclusion of ion orbit loss and intrinsic rotation in plasma fluid rotation theory
Authors: Stacey W. M. , Wilks T. M.
Published: January 2016

The preferential ion orbit loss of counter-current directed ions leaves a predominantly co-current ion distribution in the thermalized ions flowing outward through the plasma edge of tokamak plasmas, constituting a co-current intrinsic rotation. A methodology for representing this essentially kinetic phenomenon in plasma fluid theory is described and combined with a previously developed methodology of treating ion orbit particle and energy losses in fluid theory to provide a complete treatment of ion orbit loss in plasma fluid rotation theory.
A new setup for the investigation of swift heavy ion induced particle emission and surface modifications
Authors: Meinerzhagen F. , Breuer L. , Bukowska H. , Bender M. , Severin D. , Herder M. , Lebius H. , Schleberger M. , Wucher A.
Published: January 2016

The irradiation with fast ions with kinetic energies of >10 MeV leads to the deposition of a high amount of energy along their trajectory (up to several ten keV/nm). The energy is mainly transferred to the electronic subsystem and induces different secondary processes of excitations, which result in significant material modifications. A new setup to study these ion induced effects on surfaces will be described in this paper. The setup combines a variable irradiation chamber with different techniques of surface characterizations like scanning probe microscopy, time-of-flight secondary ion, and neutral mass spectrometry, as well as low energy electron diffraction under ultra high vacuum conditions, and is mounted at a beamline of the universal linear accelerator (UNILAC) of the GSI facility in Darmstadt, Germany. Here, samples can be irradiated with high-energy ions with a total kinetic energy up to several GeVs under different angles of incidence. Our setup enables the preparation and in situ analysis of different types of sample systems ranging from metals to insulators. Time-of-flight secondary ion mass spectrometry enables us to study the chemical composition of the surface, while scanning probe microscopy allows a detailed view into the local electrical and morphological conditions of the sample surface down to atomic scales. With the new setup, particle emission during irradiation as well as persistent modifications of the surface after irradiation can thus be studied. We present first data obtained with the new setup, including a novel measuring protocol for time-of-flight mass spectrometry with the GSI UNILAC accelerator.
Observation of dopant-profile independent electron transport in sub-monolayer TiOx stacked ZnO thin films grown by atomic layer deposition
Authors: Saha D. , Misra P. , Das Gangadhar , Joshi M. P. , Kukreja L. M.
Published: January 2016

Dopant-profile independent electron transport has been observed through a combined study of temperature dependent electrical resistivity and magnetoresistance measurements on a series of Ti incorporated ZnO thin films with varying degree of static-disorder. These films were grown by atomic layer deposition through in-situ vertical stacking of multiple sub-monolayers of TiOx in ZnO. Upon decreasing ZnO spacer layer thickness, electron transport smoothly evolved from a good metallic to an incipient non-metallic regime due to the intricate interplay of screening of spatial potential fluctuations and strength of static-disorder in the films. Temperature dependent phase-coherence length as extracted from the magnetotransport measurement revealed insignificant role of inter sub-monolayer scattering as an additional channel for electron dephasing, indicating that films were homogeneously disordered three-dimensional electronic systems irrespective of their dopant-profiles. Results of this study are worthy enough for both fundamental physics perspective and efficient applications of multi-stacked ZnO/TiOx structures in the emerging field of transparent oxide electronics.
Broadband metasurfaces enabling arbitrarily large delay-bandwidth products
Authors: Ginis Vincent , Tassin Philippe , Koschny Thomas , Soukoulis Costas M.
Published: January 2016

Metasurfaces allow for advanced manipulation of optical signals by imposing phase discontinuities across flat interfaces. Unfortunately, these phase shifts remain restricted to values between 0 and 2π, limiting the delay-bandwidth product of such sheets. Here, we develop an analytical tool to design metasurfaces that mimic three-dimensional materials of arbitrary thickness. In this way, we demonstrate how large phase discontinuities can be realized by combining several subwavelength Lorentzian resonances in the unit cell of the surface. Our methods open up the temporal response of metasurfaces and may lead to the construction of metasurfaces with a plethora of new optical functions.
Directional exciton-polariton photoluminescence emission from terminals of a microsphere-coupled organic waveguide
Authors: Tripathi Ravi P. N. , Chikkaraddy Rohit , Dasgupta Arindam , Pavan Kumar G. V.
Published: January 2016

We report on angle-resolved, exciton-polariton photoluminescence measurements from asymmetric terminals of a microsphere-coupled organic waveguide (MOW). The MOW architecture consisted of a SiO2 microsphere coupled with a diaminoanthroquinone mesowire, self-assembled on a glass substrate. The angle-resolved emission measurements were performed using spatially filtered Fourier-plane optical imaging method. The light emanating from the sphere-terminus had two regions of angular emission in the Fourier-plane, of which one had azimuthal angular spread as small as 10°. The emission from wire terminus was uni-directional in nature, with some light emitted beyond the critical angle of glass-air interface. Our results highlight unique directional emission characteristics of a hybrid organic waveguide geometry and may have implications on single-element, exciton-polariton based light-emitting devices and lasers.
Experimental explanation of the formation mechanism of surface mound-structures by femtosecond laser on polycrystalline Ni60Nb40
Authors: Peng Edwin , Tsubaki Alfred , Zuhlke Craig A. , Wang Meiyu , Bell Ryan , Lucis Michael J. , Anderson Troy P. , Alexander Dennis R. , Gogos George , Shield Jeffrey E.
Published: January 2016

Femtosecond laser surface processing (FLSP) is an emerging technique for creating functionalized surfaces with specialized properties, such as broadband optical absorption or superhydrophobicity/superhydrophilicity. It has been demonstrated in the past that FLSP can be used to form two distinct classes of mound-like, self-organized micro/nanostructures on the surfaces of various metals. Here, the formation mechanisms of below surface growth (BSG) and above surface growth (ASG) mounds on polycrystalline Ni60Nb40 are studied. Cross-sectional imaging of these mounds by focused ion beam milling and subsequent scanning electron microscopy revealed evidence of the unique formation processes for each class of microstructure. BSG-mound formation during FLSP did not alter the microstructure of the base material, indicating preferential valley ablation as the primary formation mechanism. For ASG-mounds, the microstructure at the peaks of the mounds was clearly different from the base material. Transmission electron microscopy revealed that hydrodynamic melting of the surface occurred during FLSP under ASG-mound forming conditions. Thus, there is a clear difference in the formation mechanisms of ASG- and BSG-mounds during FLSP.
The effect of randomness for dependency map on the robustness of interdependent lattices
Authors: Yuan Jing , Li Lixiang , Peng Haipeng , Kurths Jürgen , Xiao Jinghua , Yang Yixian
Published: January 2016

The percolation for interdependent networks with identical dependency map follows a second-order phase transition which is exactly the same with percolation on a single network, while percolation for random dependency follows a first-order phase transition. In real networks, the dependency relations between networks are neither identical nor completely random. Thus in this paper, we study the influence of randomness for dependency maps on the robustness of interdependent lattice networks. We introduce approximate entropy(ApEn) as the measure of randomness of the dependency maps. We find that there is critical ApEnc below which the percolation is continuous, but for larger ApEn, it is a first-order transition. With the increment of ApEn, the pc increases until ApEn reaching ApEnc′ and then remains almost constant. The time scale of the system shows rich properties as ApEn increases. Our results uncover that randomness is one of the important factors that lead to cascading failures of spatially interdependent networks.
Waveguide-loaded silica fibers for coupling to high-index micro-resonators
Authors: Latawiec P. , Burek M. J. , Venkataraman V. , Lončar M.
Published: January 2016

Tapered silica fibers are often used to rapidly probe the optical properties of micro-resonators. However, their low refractive index precludes phase-matching when coupling to high-index micro-resonators, reducing efficiency. Here, we demonstrate efficient optical coupling from tapered fibers to high-index micro-resonators by loading the fibers with an ancillary adiabatic waveguide-coupler fabricated via angled-etching. We demonstrate greatly enhanced coupling to a silicon multimode micro-resonator when compared to coupling via the bare fiber only. Signatures of resonator optical bistability are observed at high powers. This scheme can be applied to resonators of any size and material, increasing the functional scope of fiber coupling.
Redesign of the DFT/MRCI Hamiltonian
Authors: Lyskov Igor , Kleinschmidt Martin , Marian Christel M.
Published: January 2016

The combined density functional theory and multireference configuration interaction (DFT/MRCI) method of Grimme and Waletzke [J. Chem. Phys. 111, 5645 (1999)] is a well-established semi-empirical quantum chemical method for efficiently computing excited-state properties of organic molecules. As it turns out, the method fails to treat bi-chromophores owing to the strong dependence of the parameters on the excitation class. In this work, we present an alternative form of correcting the matrix elements of a MRCI Hamiltonian which is built from a Kohn-Sham set of orbitals. It is based on the idea of constructing individual energy shifts for each of the state functions of a configuration. The new parameterization is spin-invariant and incorporates less empirism compared to the original formulation. By utilizing damping techniques together with an algorithm of selecting important configurations for treating static electron correlation, the high computational efficiency has been preserved. The robustness of the original and redesigned Hamiltonians has been tested on experimentally known vertical excitation energies of organic molecules yielding similar statistics for the two parameterizations. Besides that, our new formulation is free from artificially low-lying doubly excited states, producing qualitatively correct and consistent results for excimers. The way of modifying matrix elements of the MRCI Hamiltonian presented here shall be considered as default choice when investigating photophysical processes of bi-chromophoric systems such as singlet fission or triplet-triplet upconversion.
Nonlinear Cherenkov difference-frequency generation exploiting birefringence of KTP
Authors: Ni R. , Du L. , Wu Y. , Hu X. P. , Zou J. , Sheng Y. , Arie A. , Zhang Y. , Zhu S. N.
Published: January 2016

In this letter, we demonstrate the realization of nonlinear Cherenkov difference-frequency generation (CDFG) exploiting the birefringence property of KTiOPO4 (KTP) crystal. The pump and signal waves were set to be along different polarizations, thus the phase-matching requirement of CDFG, which is, the refractive index of the pump wave should be smaller than that of the signal wave, was fulfilled. The radiation angles and the intensity dependence of the CDFG on the pump wave were measured, which agreed well with the theoretical ones.
Sectorial oscillation of acoustically levitated nanoparticle-coated droplet
Authors: Zang Duyang , Chen Zhen , Geng Xingguo
Published: January 2016

We have investigated the dynamics of a third mode sectorial oscillation of nanoparticle-coated droplets using acoustic levitation in combination with active modulation. The presence of nanoparticles at the droplet surface changes its oscillation amplitude and frequency. A model linking the interfacial rheology and oscillation dynamics has been proposed in which the compression modulus ε of the particle layer is introduced into the analysis. The ε obtained with the model is in good agreement with that obtained by the Wilhelmy plate approach, highlighting the important role of interfacial rheological properties in the sectorial oscillation of droplets.
Solar-cell radiance standard for absolute electroluminescence measurements and open-circuit voltage mapping of silicon solar modules
Authors: Mochizuki Toshimitsu , Kim Changsu , Yoshita Masahiro , Mitchell Jonathon , Lin Zhu , Chen Shaoqiang , Takato Hidetaka , Kanemitsu Yoshihiko , Akiyama Hidefumi
Published: January 2016

In this work, we propose and demonstrate a durable and distributable Lambertian light-emitter secondary standard using the electroluminescence (EL) of a Si solar cell. This standard is useful for calibration of the absolute sensitivity of an EL-imaging infrared camera used to acquire quick on-site measurements of the absolute EL efficiencies of individual Si solar cells in modules and arrays. The developed method enables the realization of quantitative open-circuit voltage mapping.
Sealed piezoelectric energy harvester driven by hyperbaric air load
Authors: Wang Yingting , Wang Liang , Cheng Tinghai , Song Zhaoyang , Qin Feng
Published: January 2016

In this paper, a sealed piezoelectric energy harvester is fabricated to investigate the performance of the proposed harvester when driven by a hyperbaric air load. The harvester consists of a flexible piezoceramic patch and a closed chamber. The energy from the hyperbaric air can be harvested through the deformation of the lead zirconate titanate patch. A test system is built and a prototype device is tested under various experimental conditions. The test results show that the energy generation performance of the harvester can be tuned by varying its parameters. The output voltage shows an obvious increase with increasing cycle time. When the pressure increases, the output voltage is simultaneously reduced when the flow is fixed. The maximal output voltage and power across the 1000 kΩ resistor are 70.90 V and 9.30 mW, respectively. An effective power of 3.41 mW is measured across the 200 kΩ resistor at a pressure of 0.4 MPa and a cycle time of 0.8 s with a flow of 365 l/min.
Amorphous Co(OH)2 nanosheet electrocatalyst and the physical mechanism for its high activity and long-term cycle stability
Authors: Gao Y. Q. , Li H. B. , Yang G. W.
Published: January 2016

Good conductivity is conventionally considered as a typical reference standard in terms of selecting water electrolysis catalysts. Cobalt hydroxide (Co(OH)2) has received extensive attention for its exceptional properties as a promising electrocatalysis catalyst. However, research on Co(OH)2 so far prefers to its crystal phase instead of amorphous phase because the former generally exhibits better conductivity. Here, we have demonstrated that the amorphous Co(OH)2 electrocatalyst synthesized via a simple, facile, green, and low-cost electrochemistry technique possesses high activity and long-term cycle stability in the oxygen evolution reaction (OER). The as-synthesized Co(OH)2 electrode was found to be a promising electrocatalyst for mediating OER in alkaline media, as evidenced by the overpotential of 0.38 V at a current density of 10 mA cm−2 and a Tafel slope of 68 mV dec−1. The amorphous Co(OH)2 also presented outstanding durability and its stability was just as well as that of crystalline Co(OH)2. Generally, the integrated electrochemical performances of the amorphous Co(OH)2 in the OER process were much superior to that of the crystalline Co(OH)2 materials. We also established that the short-range order, i.e., nanophase, of amorphous Co(OH)2 creates a lot of active sites for OER which can greatly promote the electrocatalysis performance of amorphous catalysts. These findings showed that the conventional understanding of selecting electrocatalysts with conductivity as a typical reference standard seems out of date for developing new catalysts at the nanometer, which actually open a door to applications of amorphous nanomaterials as an advanced electrocatalyst in the field of water oxidation.
Thermodynamic properties and solidification kinetics of intermetallic Ni7Zr2 alloy investigated by electrostatic levitation technique and theoretical calculations
Authors: Li L. H. , Hu L. , Yang S. J. , Wang W. L. , Wei B.
Published: January 2016

The thermodynamic properties, including the density, volume expansion coefficient, ratio of specific heat to emissivity of intermetallic Ni7Zr2 alloy, have been measured using the non-contact electrostatic levitation technique. These properties vary linearly with temperature at solid and liquid states, even down to the obtained maximum undercooling of 317 K. The enthalpy, glass transition, diffusion coefficient, shear viscosity, and surface tension were obtained by using molecular dynamics simulations. Ni7Zr2 has a relatively poor glass forming ability, and the glass transition temperature is determined as 1026 K. The inter-diffusivity of Ni7Zr2 alloy fitted by Vogel–Fulcher–Tammann law yields a fragility parameter of 8.49, which indicates the fragile nature of this alloy. Due to the competition of increased thermodynamic driving force and decreased atomic diffusion, the dendrite growth velocity of Ni7Zr2 compound exhibits double-exponential relationship to the undercooling. The maximum growth velocity is predicted to be 0.45 m s−1 at the undercooling of 335 K. Theoretical analysis reveals that the dendrite growth is a diffusion-controlled process and the atomic diffusion speed is only 2.0 m s−1.
Hypervelocity launching of flyers at the SG-III prototype laser facility
Authors: Shui Min , Chu Genbai , Zhu Bin , He Weihua , Xi Tao , Fan Wei , Xin Jianting , Gu Yuqiu
Published: January 2016

Experiments of laser-driven hypervelocity flyers have been conducted at the SG-III prototype laser facility. Using the continuum phase plate technique, four laser beams each with a 3-ns quadratic profile are configured to produce relatively uniform irradiated spots of diameter size either 500 μm or 2000 μm. With the former, specifically designed multi-layered flyers (polyimide/copper) were accelerated by shock impedance and reverberation techniques via direct laser ablation to a super-high averaged velocity of 55 km/s, much faster than recently reported results. Light-emission signals of shock breakout and flyer impact on flat or stepped windows were obtained that indicated good planarity and integrity for the flyer. In the latter, single-layered aluminum flyers were gradually accelerated to a terminal velocity of 11 km/s, as measured by optical velocimetry, without melting and vaporization. The results suggest that the SG-III prototype laser facility has the capability to launch high-speed flyers to create extreme conditions for investigating the science of shock compression and its equation of state.
The mioritic nation - an alternative approach to Moldovan national identity
Authors: Humă Roxana Adina
Published: January 2016

Moldova has been widely argued to be a failed nation-building project, with two national identity discourses coexisting within Moldovan society and amongst Moldovan elites: Romanianism and Moldovanism. Challenging the dominance of these discourses in the literature, this article argues that in spite of its absence from the nationalism debate in Moldova, the ballad Mioriţa is a key element for the Moldovan articulation of national identity. The analysis employs a discursive approach focused on language as a constituting phenomenon and draws from Mioriţa's appeal to the grass roots level, its banality in day-to-day life, and, more importantly, its promotion by Moldovan cultural elites. This latter part focuses specifically on the writings of novelist Ion Druţă. Druţă places Mioriţa at the very center of his construction of Moldovan national identity. He highlights its links with Moldovan history, culture, religious thinking, and geographical space, both reproducing a structure similar to the two national identity discourses, Romanianism and Moldovanism, and building on their similarities. But more importantly, Druţă's representation of national identity sheds light on the possibility of an all-encompassing Moldovan identity, overcoming the existing cleavage, and a series of mechanisms that can be employed to achieve this.
Ethnic Tatars in contention for recognition and autonomy: Bilingualism and pluri-cultural education policies in Tatarstan
Authors: Nizamova Liliya R.
Published: January 2016

This article explores the development of language and education policies in the Republic of Tatarstan, a constituent of the Russian Federation, in the context of continued decline in minorities’ political nationalism between 2000 and the 2010s. The new “model of Tatarstan” relies on a close partnership with Moscow reaffirmed by an exclusive treaty on the division of powers. However, this formality does not eliminate Tatars’ cultural contention for recognition and autonomy. The case of Tatarstan speaks to both the potential and the constraints of autonomous territories that are incapable of satisfying the needs of co-nationals living beyond their administrative borders. Language policies and education practices have become a relatively autonomous area for claim-making in defense of Tatar culture as well as bilingualism and multicultural education in the region. This study reveals the interrelationship between the two components, Tatar ethno-culturalism and “pluri-culturalism,” and the encouragement of the region's diversity in the public domain of Tatarstan. Valuable in itself, the latter in a wider context appears to be a necessary condition for protecting minority groups in multinational Russia. Thus while promoting the interests of the “titular” nationality — ethnic Tatars — Tatarstan also serves the advancement of multicultural values in present-day Russia.
Embeddedness levels in Central and East European countries as revealed by patent-related indicators
Authors: Inzelt Annamária
Published: January 2016

Central and East European countries (CEECs) still show many features of the Soviet era. Consequently, the region seems, in several ways, to have been shaped by a single universal phase of transformation. This explains, at least in part, the relatively weak patenting activities and innovation performance of these countries. This paper deals with quantitative information originating from a newly created databank and investigates CEECs, employing various patent indicators in a Triple Helix context.

New member states of the European Union (EU) from CEECs accounted for less than 1% of European patents between 1990 and 2006. This figure does not improve if patent applications are normalised according to population, and the number of patents registered in the region has evolved very little over the years. Analysing the relationships among old and new member states of the EU and their regions in terms of citations shows the pattern of intellectual linkages within Europe quite clearly. Even if CEECs feature relatively rarely in cited European publications, there are still 43 CEE affiliations recorded among the top 500 in Europe (ranked by performance). Intellectual linkages are still weak (both within the CEE area and among old and new EU member states and their regions), and the citation pattern clearly shows the importance of externally derived knowledge for CEE countries. Self-citation highlights the weakness of scientific impulses from the immediate environment to patenting activity. A very low level of self-citation may be indicative not only of low capabilities in terms of knowledge production, but also of a basic weakness in knowledge dissemination and absorption. In this respect, CEE universities have not yet shown themselves to be strong regional innovation organisers.
Hepatitis E Virus Infection Among Solid Organ Transplant Recipients at a North American Transplant Center
Authors: Sue Paul K. , Pisanic Nora , Heaney Christopher D. , Forman Michael , Valsamakis Alexandra , Jackson Annette M. , Ticehurst John R. , Montgomery Robert A. , Schwarz Kathleen B. , Nelson Kenrad E. , Karnsakul Wikrom
Published: January 2016

Background.  Autochthonous hepatitis E virus (HEV) infection has been reported in over 200 solid organ transplant (SOT) recipients since 2006, yet little is known about the burden of HEV among SOT recipients in North America. We performed a retrospective, cross-sectional study to investigate the prevalence and risk factors associated with HEV infection among SOT recipients at our institution.

Methods.  Children and adults (n = 311) who received allografts between 1988 and 2012 at the Johns Hopkins Hospital were assessed for evidence of HEV infection by testing posttransplantation serum samples for HEV antibody by enzyme immunoassay and HEV RNA by reverse transcription quantitative polymerase chain reaction. Individuals with evidence of posttransplant HEV infection (presence of anti-HEV immunoglobulin [Ig]M antibody, anti-HEV IgG seroconversion, or HEV RNA) were compared with individuals without evidence of infection and assessed for risk factors associated with infection.

Results.  Twelve individuals (4%) developed posttransplant HEV infection. Posttransplant HEV infection was associated with an increased risk for graft rejection (odds ratio, 14.2; P = .03). No individuals developed chronic infection.

Conclusions.  Solid organ transplant recipients in the United States are at risk for posttransplant HEV infection. Further studies are needed to characterize environmental risk factors and the risk of HEV infection after SOT in North America.