bluuebunny/crossref_metadata_2025 huggingface dataset:
Thinking About Other People
Authors: Schneid Erica D. , Crawford Matthew T. , Skowronski John J. , Irwin Lauren M. , Carlston Donal E.
Published: January 2015

Three experiments examined whether people spontaneously generate evaluations of target individuals under circumstances in which they are also known to generate spontaneous trait inferences (STIs). The first experiment used a standard savings-in-relearning paradigm to explore whether exposure to trait-implicative behavior descriptions facilitates the learning of evaluatively-congruent, as well as behavior-implied, personality traits. Evidence for the facilitated learning of evaluatively-congruent traits was not obtained. This led to a second experiment in which the savings-in-relearning paradigm was altered to directly assess participants’ relearning of evaluative words (good/bad). The results demonstrated that the same trait-implicative behavioral stimuli can produce both spontaneous trait inferences and spontaneous evaluations when both are measured correctly. Both of these outcomes were replicated in a third study using a false recognition paradigm. The implications of these findings for impression formation processes and for the possible independence of semantic information and evaluative information are discussed.
Forecasting the Primary Dimension of Social Perception
Authors: Kervyn Nicolas , Fiske Susan , Yzerbyt Vincent
Published: January 2015

The Stereotype Content Model (SCM) posits two fundamental dimensions of intergroup perception, warmth and competence, predicted by socio-structural dimensions of competition and status, respectively. However, the SCM has been challenged on claiming perceived competition as the socio-structural dimension that predicts perceived warmth. The current research improves by broadening warmth’s predictor (competition) to include both realistic and symbolic threat from Integrated Threat Theory (Study 1). We also measure two components of the warmth dimension: sociability and morality. Study 2 tests new items to measure both threat and warmth. The new threat items significantly improve prediction of warmth, compared with standard SCM items. Morality and sociability correlate highly and do not differ much in their predictability by competition/threat.
The Insect-Nonword IAT Revisited
Authors: Meissner Franziska , Rothermund Klaus
Published: January 2015

In 2001, Brendl and colleagues reported a reversed compatibility effect for an insect-nonword Implicit Association Test (IAT), apparently indicating more positive attitudes for insects than for neutral nonwords and therefore calling into question the validity of the IAT. According to a prominent alternative account of IAT effects, this reversed effect reflects task recoding based on salience asymmetries. To disentangle the contributions of associations and recoding, we analyzed data of an insect-nonword IAT with the ReAL model and discovered that (1) recoding is responsible for the unexpected direction of this IAT effect and (2) insects still activated negative associations. Applying the ReAL model helps to avoid misleading interpretations of IAT effects by providing independent estimates for different processes within an IAT.
Sad and Exposed, Angry and Resilient?
Authors: Wrede Olof , Ask Karl , Strömwall Leif A.
Published: January 2015

Crime victims may respond emotionally to victimization in a multitude of ways. However, little is known about how people use victims’ emotional expressions to draw inferences about their psychological status and needs. In two experiments (total N = 340), participants were presented with a victim who reacted to a crime with either anger or sadness. Additionally, victim gender (Experiment 1) and presentation modality (text, video, or audio; Experiment 2) were manipulated. Male, but not female, victims were perceived to have a stronger need for social support when expressing sadness as opposed to anger. The effect was mediated by the fact that victims expressing sadness (vs. anger) were perceived as warmer. Moreover, the effect was consistent across presentation modalities. The results show that victim gender and differences between distinct emotions need to be taken into account to understand the social consequences of victims’ emotional expressions.
Crystalline structures of polymeric hydrocarbon with 3,4-fold helical chains
Authors: Lian Chao-Sheng , Li Han-Dong , Wang Jian-Tao
Published: January 2015

Molecular hydrocarbons are well-known to polymerize under pressure to form covalently bonded frameworks. Here we predict by ab initio calculations two distinct three-dimensional hydrocarbon crystalline structures composed of 3-fold and 4-fold helical CH chains in rhombohedral ("Equation missing") and tetragonal (I41/a) symmetry, respectively. Both structures with 1:1 stoichiometry are found to be energetically more favorable than solid acetylene and cubane and even more stable than benzene II solid at high pressure. The calculations on vibrational, electronic and optical properties reveal that the new chiral hydrocarbons are dynamically stable with large bulk moduli around 200 GPa and exhibit a transparent insulating behavior with indirect band gaps of 5.9 ~ 6.7 eV and anisotropic adsorption spectra. Such forms of hydrocarbon, once synthesized, would have wide applications in mechanical, optoelectronic and biological materials.
Fast IR laser mapping ellipsometry for the study of functional organic thin films
Authors: Furchner Andreas , Sun Guoguang , Ketelsen Helge , Rappich Jörg , Hinrichs Karsten
Published: January 2015

Infrared laser ellipsometry is advanced for fast homogeneity mapping studies of functional organic thin films.
On-chip monitoring of chemical syntheses in microdroplets via surface-enhanced Raman spectroscopy
Authors: Meier T.-A. , Beulig R. J. , Klinge E. , Fuss M. , Ohla S. , Belder D.
Published: January 2015

An approach for inline monitoring of organic syntheses in a microfluidic droplet chip via surface-enhanced Raman spectroscopy is presented. In a proof of concept it was successfully applied to follow thiazole syntheses in real-time.
Metal–organic framework materials for light-harvesting and energy transfer
Authors: So Monica C. , Wiederrecht Gary P. , Mondloch Joseph E. , Hupp Joseph T. , Farha Omar K.
Published: January 2015

This contribution highlights recent work on the photon collection and energy transport behavior of metal–organic frameworks for excitonic solar cells.
Versatile functionalization of carbon electrodes with a polypyridine ligand: metallation and electrocatalytic H+ and CO2 reduction
Authors: Elgrishi Noémie , Griveau Sophie , Chambers Matthew B. , Bedioui Fethi , Fontecave Marc
Published: January 2015

A carbon electrode is functionalized with a polypyridine ligand and subsequently metallated to catalyze the electroreduction of H+ and CO2.
Joint spectroscopic and theoretical investigation of cationic cyanine dye Astrazon Orange-R: solvent viscosity controlled relaxation of excited states
Authors: Ley Christian , Bordat Patrice , di Stefano Luciano H. , Remongin Lola , Ibrahim Ahmad , Jacques Patrice , Allonas Xavier
Published: January 2015

In this paper, the first study of cationic cyanine dye Astrazon Orange-R by combined spectroscopic and theoretical investigation is presented.
Formation of a built-in field at the porphyrin/ITO interface directly proven by the time-resolved photovoltage technique
Authors: Wei Xiao , Han Li-Na , Mao Cheng-Yu , Wang De-Jun , Li Xin-Hao , Feng Ping-Yun , Chen Jie-Sheng
Published: January 2015

The time-resolved photovoltage (PV) response with reversal polarity provides direct evidence for the formation of a built-in electric field at the porphyrin/ITO interface.
Diffusion-driven and size-dependent phase changes of gallium oxide nanocrystals in a glassy host
Authors: Golubev N. V. , Ignat'eva E. S. , Sigaev V. N. , Lauria A. , De Trizio L. , Azarbod A. , Paleari A. , Lorenzi R.
Published: January 2015

We describe the evolution of γ-Ga2O3 nanocrystals in alkali-germanosilicate glass, disclosing mechanisms of nanocrystal–matrix interaction via a diffusion-driven change, into LiGa5O8 and β-Ga2O3 formation by decomposition promoted by size-dependent order–disorder polymorphism.
Thermal vibration of a single-walled carbon nanotube predicted by semiquantum molecular dynamics
Authors: Liu Rumeng , Wang Lifeng
Published: January 2015

Power spectral density of thermal vibration of a single-walled carbon nanotube predicted by semiquantum molecular dynamics.
A unique class of neutral cyclometalated platinum(ii) complexes with π-bonded benzenedithiolate: synthesis, molecular structures and tuning of luminescence properties
Authors: Sesolis Hugo , Moussa Jamal , Gontard Geoffrey , Jutand Anny , Gullo Maria Pia , Barbieri Andrea , Amouri Hani
Published: January 2015

A unique class of luminescent neutral cyclometalated platinum(ii) complexes 2–4 with π-bonded benzenedithiolate are reported including two X-ray molecular structures.
Silicon-nanowire based attachment of silicon chips for mouse embryo labelling
Authors: Durán S. , Novo S. , Duch M. , Gómez-Martínez R. , Fernández-Regúlez M. , San Paulo A. , Nogués C. , Esteve J. , Ibañez E. , Plaza J. A.
Published: January 2015

We develop chip-on-a-cell barcodes featuring silicon nanowires as nanoscale attachment to label living mouse embryos.
Experimental phase diagram of negatively supercoiled DNA measured by magnetic tweezers and fluorescence
Authors: Vlijm Rifka , Mashaghi Alireza , Bernard Stéphanie , Modesti Mauro , Dekker Cees
Published: January 2015

Phase diagram of experimentally determined DNA structures under (extreme) negative supercoiling.
Understanding aggregation-based assays: nature of protein corona and number of epitopes on antigen matters
Authors: Yeo Eugenia Li Ling , Chua Anthony Jin Shun , Parthasarathy Krupakar , Yeo Hui Yu , Ng Mah Lee , Kah James Chen Yong
Published: January 2015

In this study, we systematically examine how the nature of the protein corona on NPs, formed from either antibody or antigen, and how the number of binding sites or epitopes on the antigen affect aggregation.
In situ synchrotron X-ray diffraction with laser-heated diamond anvil cells study of Pt up to 95 GPa and 3150 K
Authors: Huang Xiaoli , Li Fangfei , Zhou Qiang , Wu Gang , Huang Yanping , Wang Lu , Liu Bingbing , Cui Tian
Published: January 2015

In situ synchrotron X-ray diffraction with laser-heated diamond anvil cells study the EOS of Pt.
Evaluating two new Schiff bases synthesized on the inhibition of corrosion of copper in NaCl solutions
Authors: Zhou Yang , Xu Shenying , Guo Lei , Zhang Shengtao , Lu Hao , Gong Yulong , Gao Fang
Published: January 2015

An AND or DSM organic film can be formed onto a copper surface in 3% NaCl solution and acts as a barrier to copper dissolution and O2reduction.
Vilsmeier cyclization of α-acetyl-α-aroyl ketene-N,S-acetals: direct and efficient synthesis of halogenated pyridin-2(1H)-ones
Authors: Yu Haifeng , Zhang Yongmei , Li Tiechun , Liao Peiqiu , Diao Quanping , Xin Guang , Meng Qingling , Hou Dongyan
Published: January 2015

An efficient synthetic route to 3-aroyl-5-formyl-4-halo pyridin-2(1H)-ones has been developed via Vilsmeier cyclization of 2-(ethylthio(arylamino)methylene)-1-alkylbutane-1,3-dione.
Piezoelectric effect of 3-D ZnO nanotetrapods
Authors: Yin Bing , Qiu Yu , Zhang Heqiu , Lei Jixue , Chang Yue , Ji Jiuyu , Luo Yingmin , Zhao Yu , Hu Lizhong
Published: January 2015

ZnO nanotetrapods could be designed as multiterminal strain sensors for enhancing sensitivity and directivity.
Selective hydrogenation of levulinic acid to γ-valerolactone over a Ru/Mg–LaO catalyst
Authors: Swarna Jaya V. , Sudhakar M. , Naveen Kumar S. , Venugopal A.
Published: January 2015

Ruthenium on a base support was developed for the conversion of biomass derived levulinic acid to γ-valerolactone at low temperature and pressure. γ-Valerolactone synthesis which can replace ethanol in petrol and in the production of jet fuels.
A simple one step process for enhancement of titanium foil dye sensitised solar cell anodes
Authors: Linnemann J. , Giorgio J. , Wagner K. , Mathieson G. , Wallace G. G. , Officer D. L.
Published: January 2015

This communication highlights a simple nitric acid treatment, which enhances the properties of titanium foil and improves the photovoltaic performance of dye sensitised solar cells.
Facile synthesis of various highly dispersive CoP nanocrystal embedded carbon matrices as efficient electrocatalysts for the hydrogen evolution reaction
Authors: Li Mian , Liu Xiaotian , Xiong Yueping , Bo Xiangjie , Zhang Yufan , Han Ce , Guo Liping
Published: January 2015

Facile synthesis of tiny CoP nanocrystal decorated porous carbon matrices as highly active non-noble-metal electrocatalysts for the HER in acidic solution.
Thermoelectric performance of SnS and SnS–SnSe solid solution
Authors: Han Ye-Mao , Zhao Jie , Zhou Min , Jiang Xing-Xing , Leng Hua-Qian , Li Lai-Feng
Published: January 2015

The thermoelectric performance improvement of SnS by introducing Se into S sublattice is reported.
Super LCST thermo-responsive nanoparticle assembly for ATP binding through the Hofmeister effect
Authors: Kashyap Smita , Jayakannan Manickam
Published: January 2015

ATP thermosensor: the first thermo-responsive super LCST amphiphile biomolecular probe was designed and developed for the detection of ATP based on the Hofmeister effect in aqueous medium.
Time–frequency audio feature extraction based on tensor representation of sparse coding
Authors: Zhang Xue‐Yuan , He Qian‐Hua
Published: January 2015

A time–frequency audio feature extraction scheme is proposed, in which features are decomposed from a frequency–time–scale tensor. The tensor, derived from a weight vector and a Gabor dictionary in sparse coding, represents the frequency, time centre and scale of transient time–frequency components with different dimensions. The distinguishing Gabor atoms are represented by individual tensor elements, and their associated coding weights are represented by tensor element values. The experimental results of sound effects classification showed performance improvement against that of sparse coding features.
Adaptive fault identification and classification methodology for smart power grids using synchronous phasor angle measurements
Authors: Gopakumar Pathirikkat , Reddy Maddikara Jaya Bharata , Mohanta Dusmanta Kumar
Published: January 2015

Smart power grids (SPGs) entail comprehensive real‐time smart monitoring and controlling strategies against contingencies such as transmission line faults. This study proposes a novel methodology for identifying and classifying transmission line faults occurring at any location in a power grid from phasor measurement unit measurements at only one of the generator buses. The proposed methodology is based on frequency domain analysis of equivalent voltage phase angle and equivalent current phase angle at the generator bus. Equivalent voltage and current phase angles are the angles made by three‐phase equivalent voltage and current phasors with respect to reference axis. These angles are estimated through Park's transformation and frequency domain analysis is performed over a fixed time span equal to inverse of system nominal frequency using fast Fourier transformation. The proposed methodology can be utilised for relaying purposes in case of single transmission lines as well as for system protection centre (SPC) applications in power grid. The significance of the fault information from the methodology is for assisting SPC in SPGs for transmission line fault detection and classification to restore the transmission lines at the earliest and initiate wide‐area control actions to maintain system stability against disturbances generated by occurrence and clearance of fault.
Calculation of the ionised field and the corona losses of high‐voltage direct current transmission lines using a finite‐difference‐based flux tracing method
Authors: Qiao Ji , Zou Jun , Li Benliang
Published: January 2015

The electric field and ion current distribution on the ground level and corona losses are the important factors for designing high‐voltage direct current (HVDC) transmission lines. This study presents a new finite‐difference‐based flux tracing (FDFT) method for analysing the ionised field. The differential equations are discretised using the finite‐difference method and the non‐linear algebraic equations are constructed. For the bipolar field, a systematic technique to set up the initial values is well established by estimating the average values of space charge density. The issues of the finite‐difference scheme, the normalisation and the selection of mesh points are elaborately discussed to have a better convergence. The boundary conditions of the ionised field equations can be enforced directly, whose benefit is that the iterative process to satisfy the boundary conditions can be completely avoided. The numerical examples show that the results obtained in this study agree well with the ones published in other literatures. The FDFT could be applied for more complicated line configuration with unequal corona‐onset electric fields and ion mobilities of opposite polarities.
Half-metallic properties, single-spin negative differential resistance, and large single-spin Seebeck effects induced by chemical doping in zigzag-edged graphene nanoribbons
Authors: Yang Xi-Feng , Zhou Wen-Qian , Hong Xue-Kun , Liu Yu-Shen , Wang Xue-Feng , Feng Jin-Fu
Published: January 2015

Ab initio calculations combining density-functional theory and nonequilibrium Green’s function are performed to investigate the effects of either single B atom or single N atom dopant in zigzag-edged graphene nanoribbons (ZGNRs) with the ferromagnetic state on the spin-dependent transport properties and thermospin performances. A spin-up (spin-down) localized state near the Fermi level can be induced by these dopants, resulting in a half-metallic property with 100% negative (positive) spin polarization at the Fermi level due to the destructive quantum interference effects. In addition, the highly spin-polarized electric current in the low bias-voltage regime and single-spin negative differential resistance in the high bias-voltage regime are also observed in these doped ZGNRs. Moreover, the large spin-up (spin-down) Seebeck coefficient and the very weak spin-down (spin-up) Seebeck effect of the B(N)-doped ZGNRs near the Fermi level are simultaneously achieved, indicating that the spin Seebeck effect is comparable to the corresponding charge Seebeck effect.
Mediating conducting polymer growth within hydrogels by controlling nucleation
Authors: Patton A. J. , Green R. A. , Poole-Warren L. A.
Published: January 2015

This study examines the efficacy of primary and secondary nucleation for electrochemical polymerisation of conductive polymers within poly(vinyl alcohol) methacrylate hydrogels. The two methods of nucleation investigated were a primary heterogeneous mechanism via introduction of conductive bulk metallic glass (Mg64Zn30Ca5Na1) particles and a secondary mechanism via introduction of “pre-polymerised” conducting polymer within the hydrogel (PEDOT:PSS). Evidence of nucleation was not seen in the bulk metallic glass loaded gels, however, the PEDOT:PSS loaded gels produced charge storage capacities over 15 mC/cm2 when sufficient polymer was loaded. These studies support the hypothesis that secondary nucleation is an efficient approach to producing stand-alone conducting hydrogels.
Multi-scale modelling of uranyl chloride solutions
Authors: Nguyen Thanh-Nghi , Duvail Magali , Villard Arnaud , Molina John Jairo , Guilbaud Philippe , Dufrêche Jean-François
Published: January 2015

Classical molecular dynamics simulations with explicit polarization have been successfully used to determine the structural and thermodynamic properties of binary aqueous solutions of uranyl chloride (UO2Cl2). Concentrated aqueous solutions of uranyl chloride have been studied to determine the hydration properties and the ion-ion interactions. The bond distances and the coordination number of the hydrated uranyl are in good agreement with available experimental data. Two stable positions of chloride in the second hydration shell of uranyl have been identified. The UO22+-Cl− association constants have also been calculated using a multi-scale approach. First, the ion-ion potential averaged over the solvent configurations at infinite dilution (McMillan-Mayer potential) was calculated to establish the dissociation/association processes of UO22+-Cl− ion pairs in aqueous solution. Then, the association constant was calculated from this potential. The value we obtained for the association constant is in good agreement with the experimental result (KUO2Cl+ = 1.48 l mol−1), but the resulting activity coefficient appears to be too low at molar concentration.
Water density fluctuations relevant to hydrophobic hydration are unaltered by attractions
Authors: Remsing Richard C. , Patel Amish J.
Published: January 2015

An understanding of density fluctuations in bulk water has made significant contributions to our understanding of the hydration and interactions of idealized, purely repulsive hydrophobic solutes. To similarly inform the hydration of realistic hydrophobic solutes that have dispersive interactions with water, here we characterize water density fluctuations in the presence of attractive fields that correspond to solute-water attractions. We find that when the attractive field acts only in the solute hydration shell, but not in the solute core, it does not significantly alter water density fluctuations in the solute core region. We further find that for a wide range of solute sizes and attraction strengths, the free energetics of turning on the attractive fields in bulk water are accurately captured by linear response theory. Our results also suggest strategies for more efficiently estimating hydration free energies of realistic solutes in bulk water and at interfaces.
Structure and dynamics of H2O vis-á-vis phenylalanine recognition at a DPPC lipid membrane via interfacial H-bond types: Insights from polarized FT-IRRAS and ADMP simulations
Authors: Sarangi Nirod Kumar , Ramesh Nivarthi , Patnaik Archita
Published: January 2015

Preferential and enantioselective interactions of l-/d-Phenylalanine (l-Phe and d-Phe) and butoxycarbonyl-protected l-/d-Phenylalanine (LPA and DPA) as guest with 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (l-DPPC) as host were tapped by using real time Fourier transform infrared reflection absorption spectroscopy (FT-IRRAS). Polarization-modulated FT-IRRAS of DPPC monolayers above the phenylalanine modified subphases depicted fine structure/conformation differences under considerations of controlled 2D surface pressure. Selective molecular recognition of d-enantiomer over l-enantiomer driven by the DPPC head group via H-bonding and electrostatic interactions was evident spectroscopically. Accordingly, binding constants (K) of 145, 346, 28, and 56 M−1 for LPA, DPA, l-Phe, and d-Phe, respectively, were estimated. The real time FT-IRRAS water bands were strictly conformation sensitive. The effect of micro-solvation on the structure and stability of the 1:1 diastereomeric l-lipid⋯, LPA/DPA and l-lipid⋯, (l/d)-Phe adducts was investigated with the aid of Atom-centered Density Matrix Propagation (ADMP), a first principle quantum mechanical molecular dynamics approach. The phosphodiester fragment was the primary site of hydration where specific solvent interactions were simulated through single- and triple- “water-phosphate” interactions, as water cluster’s “tetrahedral dice” to a “trimeric motif” transformation as a partial de-clusterization was evident. Under all the hydration patterns considered in both static and dynamic descriptions of density functional theory, l-lipid/d-amino acid enantiomer adducts continued to be stable structures while in dynamic systems, water rearranged without getting “squeezed-out” in the process of recognition. In spite of the challenging computational realm of this multiscale problem, the ADMP simulated molecular interactions complying with polarized vibrational spectroscopy unraveled a novel route to chiral recognition and interfacial water structure.
Stirring potential for indirect excitons
Authors: Hasling M. W. , Kuznetsova Y. Y. , Andreakou P. , Leonard J. R. , Calman E. V. , Dorow C. J. , Butov L. V. , Hanson M. , Gossard A. C.
Published: January 2015

We demonstrate experimental proof of principle for a stirring potential for indirect excitons. The azimuthal wavelength of this stirring potential is set by the electrode periodicity, the amplitude is controlled by the applied AC voltage, and the angular velocity is controlled by the AC frequency.
An efficient dissipative particle dynamics-based algorithm for simulating electrolyte solutions
Authors: Medina Stefan , Zhou Jiajia , Wang Zhen-Gang , Schmid Friederike
Published: January 2015

We propose an efficient simulation algorithm based on the dissipative particle dynamics (DPD) method for studying electrohydrodynamic phenomena in electrolyte fluids. The fluid flow is mimicked with DPD particles while the evolution of the concentration of the ionic species is described using Brownian pseudo particles. The method is designed especially for systems with high salt concentrations, as explicit treatment of the salt ions becomes computationally expensive. For illustration, we apply the method to electro-osmotic flow over patterned, superhydrophobic surfaces. The results are in good agreement with recent theoretical predictions.
Investigation of the nanoviscosity effect of a G-quadruplex and single-strand DNA using fluorescence correlation spectroscopy
Authors: Lee Dongkeun , Kim Minjung , Kim Soo Yong , Shin Hyosup , Kim Sok Won , Park Inho
Published: January 2015

Guanine (G)-quadruplexes are of interest because of their presence in the telomere sequence and the oncogene promoter region. Their diffusion and change of structure, especially in high viscosity solutions, are important for understanding their dynamics. G-quadruplexes may have less effective viscosity (nanoviscosity) when they are smaller than the solvent molecules. In this paper, we report the difference in the diffusion dynamics of the G-rich DNA sequences of single-strand DNA (ssDNA) and the G-quadruplex in aqueous, sucrose, and polyethylene glycol (PEG) solutions. From experiments with aqueous and sucrose solutions, we confirm that a simple diffusion model according to the viscosity is appropriate. In the PEG experiments, the nanoviscosity effect is observed according to PEG’s molecular weight. In the PEG 200 solution, both the ssDNA and the G-quadruplex possess macroviscosity. In the PEG 10 000 solution, the G-quadruplex possesses nanoviscosity and the ssDNA possesses macroviscosity, whereas, in the PEG 35 000 solution, both ssDNA and the G-quadruplex possess nanoviscosity. The experimental results are consistent with the theoretical predictions.
Extension of anisotropic effective medium theory to account for an arbitrary number of inclusion types
Authors: Myles Timothy D. , Peracchio Aldo A. , Chiu Wilson K. S.
Published: January 2015

The purpose of this work is to extend, to multi-components, a previously reported theory for calculating the effective conductivity of a two component mixture. The previously reported theory involved preferentially oriented spheroidal inclusions contained in a continuous matrix, with inclusions oriented relative to a principle axis. This approach was based on Bruggeman's unsymmetrical theory, and is extended to account for an arbitrary number of different inclusion types. The development begins from two well-known starting points; the Maxwell approach and the Maxwell-Garnett approach for dilute mixtures. It is shown that despite these two different starting points, the final Bruggeman type equation is the same. As a means of validating the developed expression, comparisons are made to several existing effective medium theories. It is shown that these existing theories coincide with the developed equations for the appropriate parameter set. Finally, a few example mixtures are considered to demonstrate the effect of multiple inclusions on the calculated effective property. Inclusion types of different conductivities, shapes, and orientations are considered and each of the aforementioned properties is shown to have a potentially significant impact on the calculated mixture property.
Restricted Hartree Fock using complex-valued orbitals: A long-known but neglected tool in electronic structure theory
Authors: Small David W. , Sundstrom Eric J. , Head-Gordon Martin
Published: January 2015

Restricted Hartree Fock using complex-valued orbitals (cRHF) is studied. We introduce an orbital pairing theorem, with which we obtain a concise connection between cRHF and real-valued RHF, and use it to uncover the close relationship between cRHF, unrestricted Hartree Fock, and generalized valence bond perfect pairing. This enables an intuition for cRHF, contrasting with the generally unintuitive nature of complex orbitals. We also describe an efficient computer implementation of cRHF and its corresponding stability analysis. By applying cRHF to the Be + H2 insertion reaction, a Woodward-Hoffmann violating reaction, and a symmetry-driven conical intersection, we demonstrate in genuine molecular systems that cRHF is capable of removing certain potential energy surface singularities that plague real-valued RHF and related methods. This complements earlier work that showed this capability in a model system. We also describe how cRHF is the preferred RHF method for certain radicaloid systems like singlet oxygen and antiaromatic molecules. For singlet O2, we show that standard methods fail even at the equilibrium geometry. An implication of this work is that, regardless of their individual efficacies, cRHF solutions to the HF equations are fairly commonplace.
Solvatochromism of 9,10-phenanthrenequinone: An electronic and resonance Raman spectroscopic study
Authors: Ravi Kumar Venkatraman , Rajkumar Nagappan , Umapathy Siva
Published: January 2015

Solvent effects play a vital role in various chemical, physical, and biological processes. To gain a fundamental understanding of the solute-solvent interactions and their implications on the energy level re-ordering and structure, UV-VIS absorption, resonance Raman spectroscopic, and density functional theory calculation studies on 9,10-phenanthrenequinone (PQ) in different solvents of diverse solvent polarity has been carried out. The solvatochromic analysis of the absorption spectra of PQ in protic dipolar solvents suggests that the longest (1n-π1*; S1 state) and the shorter (1π-π1*; S2 state) wavelength band undergoes a hypsochromic and bathochromic shift due to intermolecular hydrogen bond weakening and strengthening, respectively. It also indicates that hydrogen bonding plays a major role in the differential solvation of the S2 state relative to the ground state. Raman excitation profiles of PQ (400–1800 cm−1) in various solvents followed their corresponding absorption spectra therefore the enhancements on resonant excitation are from single-state rather than mixed states. The hyperchromism of the longer wavelength band is attributed to intensity borrowing from the nearby allowed electronic transition through vibronic coupling. Computational calculation with C2ν symmetry constraint on the S2 state resulted in an imaginary frequency along the low-frequency out-of-plane torsional modes involving the C=O site and therefore, we hypothesize that this mode could be involved in the vibronic coupling.
Tensor decomposition techniques in the solution of vibrational coupled cluster response theory eigenvalue equations
Authors: Godtliebsen Ian H. , Hansen Mads Bøttger , Christiansen Ove
Published: January 2015

We show how the eigenvalue equations of vibrational coupled cluster response theory can be solved using a subspace projection method with Davidson update, where basis vectors are stacked tensors decomposed into canonical (CP, Candecomp/Parafac) form. In each update step, new vectors are first orthogonalized to old vectors, followed by a tensor decomposition to a prescribed threshold TCP. The algorithm can provide excitation energies and eigenvectors of similar accuracy as a full vector approach and with only a very modest increase in the number of vectors required for convergence. The algorithm is illustrated with sample calculations for formaldehyde, 1,2,5-thiadiazole, and water. Analysis of the formaldehyde and thiadiazole calculations illustrate a number of interesting features of the algorithm. For example, the tensor decomposition threshold is optimally put to rather loose values, such as TCP = 10−2. With such thresholds for the tensor decompositions, the original eigenvalue equations can still be solved accurately. It is thus possible to directly calculate vibrational wave functions in tensor decomposed format.
High efficiency solar cells combining a perovskite and a silicon heterojunction solar cells via an optical splitting system
Authors: Uzu Hisashi , Ichikawa Mitsuru , Hino Masashi , Nakano Kunihiro , Meguro Tomomi , Hernández José Luis , Kim Hui-Seon , Park Nam-Gyu , Yamamoto Kenji
Published: January 2015

We have applied an optical splitting system in order to achieve very high conversion efficiency for a full spectrum multi-junction solar cell. This system consists of multiple solar cells with different band gap optically coupled via an “optical splitter.” An optical splitter is a multi-layered beam splitter with very high reflection in the shorter-wave-length range and very high transmission in the longer-wave-length range. By splitting the incident solar spectrum and distributing it to each solar cell, the solar energy can be managed more efficiently. We have fabricated optical splitters and used them with a wide-gap amorphous silicon (a-Si) solar cell or a CH3NH3PbI3 perovskite solar cell as top cells, combined with mono-crystalline silicon heterojunction (HJ) solar cells as bottom cells. We have achieved with a 550 nm cutoff splitter an active area conversion efficiency of over 25% using a-Si and HJ solar cells and 28% using perovskite and HJ solar cells.
Research on anisotropy of fusion-produced protons and neutrons emission from high-current plasma-focus discharges
Authors: Malinowski K. , Skladnik-Sadowska E. , Sadowski M. J. , Szydlowski A. , Czaus K. , Kwiatkowski R. , Zaloga D. , Paduch M. , Zielinska E.
Published: January 2015

The paper concerns fast protons and neutrons from D-D fusion reactions in a Plasma-Focus-1000U facility. Measurements were performed with nuclear-track detectors arranged in “sandwiches” of an Al-foil and two PM-355 detectors separated by a polyethylene-plate. The Al-foil eliminated all primary deuterons, but was penetrable for fast fusion protons. The foil and first PM-355 detector were penetrable for fast neutrons, which were converted into recoil-protons in the polyethylene and recorded in the second PM-355 detector. The “sandwiches” were irradiated by discharges of comparable neutron-yields. Analyses of etched tracks and computer simulations of the fusion-products behavior in the detectors were performed.
Note: A microfluidic freezer based on evaporative cooling of atomized aqueous microdroplets
Authors: Song Jin , Chung Minsub , Kim Dohyun
Published: January 2015

We report for the first time water-based evaporative cooling integrated into a microfluidic chip for temperature control and freezing of biological solution. We opt for water as a nontoxic, effective refrigerant. Aqueous solutions are atomized in our device and evaporation of microdroplets under vacuum removes heat effectively. We achieve rapid cooling (−5.1 °C/s) and a low freezing temperature (−14.1 °C). Using this approach, we demonstrate freezing of deionized water and protein solution. Our simple, yet effective cooling device may improve many microfluidic applications currently relying on external power-hungry instruments for cooling and freezing.
Nudged-elastic band method with two climbing images: Finding transition states in complex energy landscapes
Authors: Zarkevich Nikolai A. , Johnson Duane D.
Published: January 2015

The nudged-elastic band (NEB) method is modified with concomitant two climbing images (C2-NEB) to find a transition state (TS) in complex energy landscapes, such as those with a serpentine minimal energy path (MEP). If a single climbing image (C1-NEB) successfully finds the TS, then C2-NEB finds it too. However, improved stability of C2-NEB makes it suitable for more complex cases, where C1-NEB misses the TS because the MEP and NEB directions near the saddle point are different. Generally, C2-NEB not only finds the TS, but also guarantees, by construction, that the climbing images approach it from the opposite sides along the MEP. In addition, C2-NEB provides an accuracy estimate from the three images: the highest-energy one and its climbing neighbors. C2-NEB is suitable for fixed-cell NEB and the generalized solid-state NEB.
Surface plasmon sensors on ZnO:Ga layer surfaces: Electric field distributions and absorption-sensitivity enhancements
Authors: Matsui Hiroaki , Ikehata Akifumi , Tabata Hitoshi
Published: January 2015

Surface plasmon resonances (SPRs) on ZnO:Ga layer surfaces (ZnO-SPR) enhanced absorption bands related to molecular-vibrations (OH and CH3 modes) in the near-infrared range by controlling layer thickness. These behaviors were due to the interaction between SPR excitations and molecular vibrations. Further investigation revealed that the high detection sensitivity of SPRs on ZnO:Ga layer surfaces was 6837 nm/RIU using water and methanol mixtures. The detection region of ZnO-SPR was limited within several hundred nanometers from the layer surfaces, which is discussed relative to theoretical analysis of field distributions and spatial coherence of SPRs on ZnO:Ga layer surfaces.
Van der Waals coefficients beyond the classical shell model
Authors: Tao Jianmin , Fang Yuan , Hao Pan , Scuseria G. E. , Ruzsinszky Adrienn , Perdew John P.
Published: January 2015

Van der Waals (vdW) coefficients can be accurately generated and understood by modelling the dynamic multipole polarizability of each interacting object. Accurate static polarizabilities are the key to accurate dynamic polarizabilities and vdW coefficients. In this work, we present and study in detail a hollow-sphere model for the dynamic multipole polarizability proposed recently by two of the present authors (JT and JPP) to simulate the vdW coefficients for inhomogeneous systems that allow for a cavity. The inputs to this model are the accurate static multipole polarizabilities and the electron density. A simplification of the full hollow-sphere model, the single-frequency approximation (SFA), circumvents the need for a detailed electron density and for a double numerical integration over space. We find that the hollow-sphere model in SFA is not only accurate for nanoclusters and cage molecules (e.g., fullerenes) but also yields vdW coefficients among atoms, fullerenes, and small clusters in good agreement with expensive time-dependent density functional calculations. However, the classical shell model (CSM), which inputs the static dipole polarizabilities and estimates the static higher-order multipole polarizabilities therefrom, is accurate for the higher-order vdW coefficients only when the interacting objects are large. For the lowest-order vdW coefficient C6, SFA and CSM are exactly the same. The higher-order (C8 and C10) terms of the vdW expansion can be almost as important as the C6 term in molecular crystals. Application to a variety of clusters shows that there is strong non-additivity of the long-range vdW interactions between nanoclusters.
Three-dimensional potential energy surface of Ar–CO
Authors: Sumiyoshi Yoshihiro , Endo Yasuki
Published: January 2015

A three-dimensional intermolecular potential energy surface of the Ar–CO complex has been determined by fitting most of the previously reported spectroscopic data, where observed transition frequencies by microwave, millimeter-wave, submillimeter-wave, and infrared spectroscopy were reproduced simultaneously within their experimental accuracies. A free rotor model Hamiltonian considering all the freedom of motions for an atom-diatom system was applied to calculate vibration-rotation energies. A three-dimensional potential energy surface obtained by ab initio calculations at the CCSD(T)-F12b/aug-cc-pV5Z level of theory was parameterized by a model function consisting of 46 parameters. They were used as initial values for the least-squares analysis of the experimental data. A total of 20 parameters were optimized to reproduce all the spectroscopic data.
Effect of Si additions on thermal stability and the phase transition sequence of sputtered amorphous alumina thin films
Authors: Bolvardi H. , to Baben M. , Nahif F. , Music D. , Schnabel V. , Shaha K. P. , Mráz S. , Bednarcik J. , Michalikova J. , Schneider J. M.
Published: January 2015

Si-alloyed amorphous alumina coatings having a silicon concentration of 0 to 2.7 at. % were deposited by combinatorial reactive pulsed DC magnetron sputtering of Al and Al-Si (90-10 at. %) split segments in Ar/O2 atmosphere. The effect of Si alloying on thermal stability of the as-deposited amorphous alumina thin films and the phase formation sequence was evaluated by using differential scanning calorimetry and X-ray diffraction. The thermal stability window of the amorphous phase containing 2.7 at. % of Si was increased by more than 100 °C compared to that of the unalloyed phase. A similar retarding effect of Si alloying was also observed for the α-Al2O3 formation temperature, which increased by more than 120 °C. While for the latter retardation, the evidence for the presence of SiO2 at the grain boundaries was presented previously, this obviously cannot explain the stability enhancement reported here for the amorphous phase. Based on density functional theory molecular dynamics simulations and synchrotron X-ray diffraction experiments for amorphous Al2O3 with and without Si incorporation, we suggest that the experimentally identified enhanced thermal stability of amorphous alumina with addition of Si is due to the formation of shorter and stronger Si–O bonds as compared to Al–O bonds.
Screening ion-channel ligand interactions with passive pumping in a microfluidic bilayer lipid membrane chip
Authors: Saha Shimul C. , Powl Andrew M. , Wallace B. A. , de Planque Maurits R. R. , Morgan Hywel
Published: January 2015

We describe a scalable artificial bilayer lipid membrane platform for rapid electrophysiological screening of ion channels and transporters. A passive pumping method is used to flow microliter volumes of ligand solution across a suspended bilayer within a microfluidic chip. Bilayers are stable at flow rates up to ∼0.5 μl/min. Phospholipid bilayers are formed across a photolithographically defined aperture made in a dry film resist within the microfluidic chip. Bilayers are stable for many days and the low shunt capacitance of the thin film support gives low-noise high-quality single ion channel recording. Dose-dependent transient blocking of α-hemolysin with β-cyclodextrin (β-CD) and polyethylene glycol is demonstrated and dose-dependent blocking studies of the KcsA potassium channel with tetraethylammonium show the potential for determining IC50 values. The assays are fast (30 min for a complete IC50 curve) and simple and require very small amounts of compounds (100 μg in 15 μl). The technology can be scaled so that multiple bilayers can be addressed, providing a screening platform for ion channels, transporters, and nanopores.
Generalized Batchelor functions of isotropic turbulence
Authors: Gravanis Elias , Akylas Evangelos
Published: January 2015

We generalize Batchelor’s parameterization of the autocorrelation functions of isotropic turbulence in a form involving a product expansion with multiple small scales. The richer small scale structure acquired this way, compared to the usual Batchelor function, is necessary so that the associated energy spectrum approximate well actual spectra in the universal equilibrium range. We propose that the generalized function provides an approximation of arbitrary accuracy for actual spectra of isotropic turbulence over the universal equilibrium range. The degree of accuracy depends on the number of higher moments which are determinable and it is reflected in the number of small scales involved. The energy spectrum of the generalized function is derived, and for the case of two small scales is compared with data from high-resolution direct numerical simulations. We show that the compensated spectra (which illustrate the bottleneck effect) and dissipation spectra are encapsulated excellently, in accordance with our proposal.
Improved Ga grading of sequentially produced Cu(In,Ga)Se2 solar cells studied by high resolution X-ray fluorescence
Authors: Schöppe Philipp , Schnohr Claudia S. , Oertel Michael , Kusch Alexander , Johannes Andreas , Eckner Stefanie , Burghammer Manfred , Martínez-Criado Gema , Reislöhner Udo , Ronning Carsten
Published: January 2015

There is particular interest to investigate compositional inhomogeneity of Cu(In,Ga)Se2 solar cell absorbers. We introduce an approach in which focused ion beam prepared thin lamellas of complete solar cell devices are scanned with a highly focused synchrotron X-ray beam. Analyzing the resulting fluorescence radiation ensures high resolution compositional analysis combined with high spatial resolution. Thus, we are able to detect subtle variations of the Ga/(Ga + In) ratio down to 0.01 on a submicrometer scale. We observed that for sequentially processed solar cells a higher selenization temperature leads to absorbers with almost homogenous Ga/(Ga + In) ratio, which significantly improved the conversion efficiency.
Electrowetting on semiconductors
Authors: Palma Cesar , Deegan Robert
Published: January 2015

Applying a voltage difference between a conductor and a sessile droplet sitting on a thin dielectric film separating it from the conductor will cause the drop to spread. When the conductor is a good metal, the change of the drop's contact angle due to the voltage is given by the Young-Lippmann (YL) equation. Here, we report experiments with lightly doped, single crystal silicon as the conductive electrode. We derive a modified YL equation that includes effects due to the semiconductor and contact line pinning. We show that light induces a non-reversible wetting transition, and that our model agrees well with our experimental results.
Low-temperature D+ + H2 reaction: A time-dependent coupled wave-packet study in hyperspherical coordinates
Authors: Sahoo Tapas , Ghosh Sandip , Adhikari Satrajit , Sharma Rahul , Varandas António J. C.
Published: January 2015

A recently proposed coupled three-dimensional time-dependent wave-packet formalism in hyperspherical coordinates is shown to yield accurate results for the reactive non-charge transfer process in the title system at collision energies as low as 100 K, where the lowest sheet of the accurate double many body expansion form for the singlet H3+ is used. The results are compared with available experimental data as well as time-independent calculations, and the agreement shown to be generally good.
Exponential of a matrix, a nonlinear problem, and quantum gates
Authors: Steeb Willi-Hans , Hardy Yorick
Published: January 2015

We describe solutions of the matrix equation exp(z(A − In)) = A, where z ∈ ℂ. Applications in quantum computing are given. Both normal and non-normal matrices are studied. For normal matrices, the Lambert W-function plays a central role.