bluuebunny/crossref_metadata_2025 huggingface dataset:
SELENBP1 expression in the prefrontal cortex of subjects with schizophrenia
Authors: Udawela M , Money T T , Neo J , Seo M S , Scarr E , Dean B , Everall I P
Published: August 2015

Selenium binding protein 1 (SELENBP1) messenger RNA (mRNA) has previously been shown to be upregulated in the brain and blood from subjects with schizophrenia. We aimed to validate these findings in a new cohort using real-time PCR in Brodmann’s Area (BA) 9, and to determine the disease specificity of increased SELENBP1 expression by measuring SELENBP1 mRNA in subjects with major depressive disorder and bipolar disorder. We then extended the study to include other cortical regions such as BA8 and BA44. SELENBP1 mRNA was higher in BA9 (P=0.001), BA8 (P=0.003) and BA44 (P=0.0007) from subjects with schizophrenia. Conversely, in affective disorders, there was no significant difference in SELENBP1 mRNA in BA9 (P=0.67), suggesting that the upregulation may be diagnosis specific. Measurement of SELENBP1 protein levels showed that changes in mRNA did not translate to changes in protein. In addition, chronic treatment of rats with antipsychotics did not significantly affect the expression of Selenbp1 in the cortex (P=0.24). Our data show that elevated SELENBP1 transcript expression is widespread throughout the prefrontal cortex in schizophrenia, and confirm that this change is a consistent feature of schizophrenia and not a simple drug effect.
Supramolecular nanofibers of self-assembling peptides and proteins for protein delivery
Authors: Wang Huaimin , Wang Youzhi , Zhang Xiaoli , Hu Yawen , Yi Xiaoyong , Ma Linsha , Zhou Hao , Long Jiafu , Liu Qian , Yang Zhimou
Published: August 2015

Supramolecular nanofibers of proteins and peptides could be used for intracellular protein delivery.
Mechanistic elucidation of C–H oxidation by electron rich non-heme iron(iv)–oxo at room temperature
Authors: Rana Sujoy , Dey Aniruddha , Maiti Debabrata
Published: August 2015

Non-heme iron(iv)–oxo species form iron(iii) intermediates during hydrogen atom abstraction (HAA) from the C–H bond.
pH-Responsive supramolecular vesicles assembled by water-soluble pillar[5]arene and a BODIPY photosensitizer for chemo-photodynamic dual therapy
Authors: Meng Lu-Bo , Zhang Wenyi , Li Dongqi , Li Yan , Hu Xiao-Yu , Wang Leyong , Li Guigen
Published: August 2015

Supramolecular vesicles assembled by water-soluble pillar[5]arene and a BODIPY photosensitizer are constructed for chemo- and photodynamic dual therapy.
Theoretical spectroscopic studies on chemical and electronic structures of arginylglycine
Authors: Li Hongbao , Li Leilei , Jiang Jun , Lin Zijing , Luo Yi
Published: August 2015

The global minimum of the dipeptide ArgGly is found to be in the canonical form, rather than the zwitterionic form.
The potential versus current state of water splitting with hematite
Authors: Zandi Omid , Hamann Thomas W.
Published: August 2015

This review describes the potential of hematite as a photoanode material for photoelectrochemical (PEC) water splitting.
Understanding and exploiting nanoparticles' intimacy with the blood vessel and blood
Authors: Setyawati Magdiel Inggrid , Tay Chor Yong , Docter Dominic , Stauber Roland H. , Leong David Tai
Published: August 2015

Understanding the interaction between nanoparticles, blood and blood vessel cells for a better designed of nanomedicine.
Supramolecular fluorescence enhancement via coordination-driven self-assembly in bis-picolylcalixarene blue-emitting M2L2Xn macrocycles
Authors: Guzmán-Percástegui Edmundo , Vonlanthen Mireille , Quiroz-García Beatriz , Flores-Alamo Marcos , Rivera Ernesto , Castillo Ivan
Published: August 2015

Photoactive macrocycles are obtained through coordination-driven self-assembly between calixarene L and Zn2+, Pd2+, Ag+, and Cd2+. Blue emission enhancement of L is observed upon assembly. M2L2Xn act as turn-off sensors for picric acid.
Application of computational chemistry in understanding the mechanisms of mercury removal technologies: a review
Authors: Ling Lixia , Fan Maohong , Wang Baojun , Zhang Riguang
Published: August 2015

Computational chemistry is a useful method to understand the mechanisms of mercury removal.
Gene expression as an indicator of the molecular response and toxicity in the bacterium Shewanella oneidensis and the water flea Daphnia magna exposed to functionalized gold nanoparticles
Authors: Qiu T. A. , Bozich J. S. , Lohse S. E. , Vartanian A. M. , Jacob L. M. , Meyer B. M. , Gunsolus I. L. , Niemuth N. J. , Murphy C. J. , Haynes C. L. , Klaper R. D.
Published: August 2015

Gene expression patterns indicate different impacts of charged nanoparticles across two model species.
Economic analysis of CNT lithium-ion battery manufacturing
Authors: Hakimian A. , Kamarthi S. , Erbis S. , Abraham K. M. , Cullinane T. P. , Isaacs J. A.
Published: August 2015

Although MWCNT lithium battery costs increase when proactively preventing manufacturing worker exposures, costs per unit of specific energy decrease overall.
Applying the water safety plan to water reuse: towards a conceptual risk management framework
Authors: Goodwin D. , Raffin M. , Jeffrey P. , Smith H. M.
Published: August 2015

The Water Safety Plan (WSP) is receiving increasing attention as a recommended risk management approach for water reuse through a range of research programmes, guidelines and standards.
International research agency perspectives on potable water reuse
Authors: Burgess Jo , Meeker Melissa , Minton Julie , O'Donohue Mark
Published: August 2015

This paper summarises the technical, social and political issues regarding direct potable reuse in the USA, Australia, and South Africa.
Epoxy thermosets from model mixtures of the lignin-to-vanillin process
Authors: Fache M. , Boutevin B. , Caillol S.
Published: August 2015

Bio-based epoxy thermosets with good thermo-mechanical properties were prepared from model mixtures of products from the lignin-to-vanillin process.
Three-dimensional elemental imaging of Li-ion solid-state electrolytes using fs-laser induced breakdown spectroscopy (LIBS)
Authors: Hou Huaming , Cheng Lei , Richardson Thomas , Chen Guoying , Doeff Marca , Zheng Ronger , Russo Richard , Zorba Vassilia
Published: August 2015

We demonstrate a new way for direct 3D chemical imaging of Li-ion battery solid-electrolytes by combining femtosecond-LIBS with advanced visualization protocols.
Guiding pancreatic beta cells to target electrodes in a whole-cell biosensor for diabetes
Authors: Pedraza Eileen , Karajić Aleksandar , Raoux Matthieu , Perrier Romain , Pirog Antoine , Lebreton Fanny , Arbault Stéphane , Gaitan Julien , Renaud Sylvie , Kuhn Alexander , Lang Jochen
Published: August 2015

We present a method for delivering cells to target electrodes of a whole-cell bioelectronic sensor for multi-parametric sensing of glucose and physiological hormone regulators.
Liquid phase solvent bonding of plastic microfluidic devices assisted by retention grooves
Authors: Wan Alwin M. D. , Sadri Amir , Young Edmond W. K.
Published: August 2015

A novel method using retention grooves enables consistent, high quality liquid phase solvent bonding of plastic microfluidic devices.
Human genes with a greater number of transcript variants tend to show biological features of housekeeping and essential genes
Authors: Ryu Jae Yong , Kim Hyun Uk , Lee Sang Yup
Published: August 2015

Human genes with a greater number of transcript variants are more likely to play functionally important roles such as cellular maintenance and survival.
The blood–cerebrospinal fluid barrier – first evidence for an active transport of organic mercury compounds out of the brain
Authors: Lohren Hanna , Bornhorst Julia , Galla Hans-Joachim , Schwerdtle Tanja
Published: August 2015

Hg strongly transfers across the blood–CSF barrier towards the blood side after incubation with organic Hg compounds.
Loading of chromenones on superparamagnetic iron oxide-modified dextran core–shell nanoparticles: openness to bind to β-cyclodextrin and DNA
Authors: Yousuf Sameena , Enoch Israel V. M. V. , Selvakumar Paulraj Mosae , Premnath Dhanaraj
Published: August 2015

Chromenones are loaded on SPIONs. They are available for binding to β-cyclodextrin and to DNA.
A dual functional peptide carrying in vitro selected catalytic and binding activities
Authors: Zhu Liping , Wang Wei , Zhao Haixu , Xu Muye , Tada Seiichi , Uzawa Takanori , Liu Mingzhe , Ito Yoshihiro
Published: August 2015

When minimal functional sequences are used, it is possible to integrate multiple functions on a single peptide chain, like a “single stroke drawing”.
Copper-catalyzed multi-component synthesis of acrylamidines and benzoimidazoles
Authors: Wang Jinjin , Lu Ping , Wang Yanguang
Published: August 2015

Acrylamidines were synthesized via the copper-catalyzed three-component reaction of propargyl acetates, sulfonyl azides and amines, which are readily accessible materials.
Synthesis, photophysical and anticancer study of D-ring extended estrone analogues
Authors: Maurya Hardesh K. , Hasanain Mohammad , Kumar Ch. Pavan , Vasudeva Prema G. , Sarkar Jayanta , Chandrasekharam M. , Gupta Atul
Published: August 2015

A concise route for highly substituted ring extended estrone analogues has been developed. The photophysical and biological study of these compounds revealed their efficacy as possible fluorescence probes in cancer chemotherapy.
Organic dyes for the sensitization of nanostructured ZnO photoanodes: effect of the anchoring functions
Authors: Idígoras J. , Godfroy M. , Joly D. , Todinova A. , Maldivi P. , Oskam G. , Demadrille R. , Anta J. A.
Published: August 2015

Nanocrystalline ZnO performs remarkably well as photoanode when it is sensitized with fully organic D–π–A dyes.
Formation of cyclobutane thymine dimers by tiaprofenic acid and its photoproducts: approach to the photosensitizer triplet state energy limit value
Authors: Michaud Sandra , Bordeau Guillaume , Sartor Valérie , Bourdelande Jose Luis , Hernando Jordi , Guirado Gonzalo , Chouini-Lalanne Nadia
Published: August 2015

Tiaprofenic acid family photosensitizes cyclobutane thymine dimer formation allowing to approach the lower limit threshold of a photosensitizer triplet state energy to excite the triplet state of thymine in DNA.
Enhanced biological performance on nano-microstructured surfaces assembled by SrTiO3 cubic nanocrystals
Authors: Shou Guohui , Dong Lingqing , Wang Xiaozhao , Cheng Kui , Weng Wenjian
Published: August 2015

Controlling protein adsorption on material surfaces can offer significant opportunities in terms of engineering the material–cell interactions.
Ligand survey results in identification of PNP pincer complexes of iridium as long-lived and chemoselective catalysts for dehydrogenative borylation of terminal alkynes
Authors: Lee Chun-I , DeMott Jessica C. , Pell Christopher J. , Christopher Alyson , Zhou Jia , Bhuvanesh Nattamai , Ozerov Oleg V.
Published: August 2015

A new, highly active Ir catalyst for dehydrogenative borylation of terminal alkynes (DHBTA) has been identified.
Nonlinear electro-osmosis of dilute non-adsorbing polymer solutions with low ionic strength
Authors: Uematsu Yuki
Published: August 2015

Nonlinear electro-osmosis of polymer solutions with low salinity is investigated using Brownian dynamics simulation and a kinetic theory.
Near-wall dynamics of concentrated hard-sphere suspensions: comparison of evanescent wave DLS experiments, virial approximation and simulations
Authors: Liu Yi , Bławzdziewicz Jerzy , Cichocki Bogdan , Dhont Jan K. G. , Lisicki Maciej , Wajnryb Eligiusz , Young Y.-N. , Lang Peter R.
Published: August 2015

Comparing to EWDLS-experiments and simulation shows a virial approximation for colloidal near-wall dynamics to be valid up to intermediate densities.
Adsorption of soft particles at fluid interfaces
Authors: Style Robert W. , Isa Lucio , Dufresne Eric R.
Published: August 2015

We explain why soft particles make good emulsifiers by analysing their deformations at a fluid–fluid interface.
A B4C nanowire and carbon nanotube composite as a novel bifunctional electrocatalyst for high energy lithium oxygen batteries
Authors: Luo Wen-Bin , Chou Shu-Lei , Wang Jia-Zhao , Liu Hua-Kun
Published: August 2015

B4C nanowire, a novel bifunctional electrocatalyst, is used as an electrocatalyst for Li–O2batteries, with favourable rechargeability, and high round-trip efficiency.
Three-dimensional CNT/graphene–sulfur hybrid sponges with high sulfur loading as superior-capacity cathodes for lithium–sulfur batteries
Authors: He Jiarui , Chen Yuanfu , Li Pingjian , Fu Fei , Wang Zegao , Zhang Wanli
Published: August 2015

A facile method is presented to synthesize three-dimensional carbon nanotube/graphene–sulfur (3DCGS) sponge with a high sulfur loading of 80.1%.
Cypress leaf-like Sb as anode material for high-performance sodium-ion batteries
Authors: Hou Hongshuai , Jing Mingjun , Zhang Yan , Chen Jun , Huang Zhaodong , Ji Xiaobo
Published: August 2015

Cypress leaf-like Sb (CL-Sb) was obtained via a facile chemical replacement reaction. The prepared CL-Sb was firstly applied as an anode material for sodium-ion batteries, displaying outstanding electrochemical performances with superior rate capability and excellent cycle stability due to its unique morphology.
Cobalt selenide: a versatile cocatalyst for photocatalytic water oxidation with visible light
Authors: Zhang Guigang , Zang Shaohong , Lan Zhi-An , Huang Caijin , Li Guosheng , Wang Xinchen
Published: August 2015

A versatile sustainable cocatalyst has been incorporated with g-C3N4to construct surface contacts for photocatalytic water oxidation.
Porphyrins as nanoreactors in the carbon dioxide capture and conversion: a review
Authors: Kumar Santosh , Wani Mohmmad. Y. , Arranja Cláudia T. , e Silva Joana de A. , Avula B. , Sobral Abilio J. F. N.
Published: August 2015

On account of their unique properties and robust structures, porphyrins are nature's favorite catalysts.
Stimulatory effects of the fast setting and suitable degrading Ca–Si–Mg cement on both cementogenesis and angiogenesis differentiation of human periodontal ligament cells
Authors: Chen Yi-Wen , Yeh Chia-Hung , Shie Ming-You
Published: August 2015

The purpose of this study is to develop a fast setting and suitable degrading Mg–calcium silicate cement (Mg–CS) and a mechanism using Mg ions to stimulate human periodontal ligament cells (hPDLCs).
A dopamine responsive nano-container for the treatment of pheochromocytoma cells based on mesoporous silica nanoparticles capped with DNA-templated silver nanoparticles
Authors: Yang Xue , He Dinggeng , He Xiaoxiao , Wang Kemin , Zou Zhen , Yang Xiaoxiao , He Xing , Xiong Jun , Li Siqi , Li Liling
Published: August 2015

A novel DA responsive delivery system was developed for the treatment of pheochromocytoma cells based on MSNs capped with DNA-templated AgNPs.
Aqueous synthesis of polyhedral “brick-like” iron oxide nanoparticles for hyperthermia and T2MRI contrast enhancement
Authors: Worden Matthew , Bruckman Michael A. , Kim Min-Ho , Steinmetz Nicole F. , Kikkawa James M. , LaSpina Catherine , Hegmann Torsten
Published: August 2015

Iron oxide nanobricks prepared by co-precipitation in lyotropic liquid crystal phases are versatile and effective theranostic materials for magnetic hyperthermia,T2MRI contrast enhancement and differential cell internalization.
The facile one-step aqueous synthesis of near-infrared emitting Cu+ doped CdS quantum dots as fluorescence bioimaging probes with high quantum yield and low cytotoxicity
Authors: Sun Ting-Ting , Wu Ming , He Xi-Wen , Li Wen-You , Feng Xi-Zeng
Published: August 2015

The water-soluble Cu+:CdS QDs with NIR emission and high PLQY were prepared in a N2 atmosphere and employed as bioimaging probes for 3T3 cells.
Cross-linkable random copolymers as dielectrics for low-voltage organic field-effect transistors
Authors: Reis Simas E. , Kang E. S. H. , Gassmann A. , Katholing E. , Janietz S. , von Seggern H.
Published: August 2015

A novel co- and terpolymer utilizing cross-linkable azide groups has been proven to be applicable as thin-film dielectric in organic field effect transistors. Reliable operation with saturation currents above Vg = 4 to 5 V can be achieved for a dielectric thickness of smaller than 100 nm.
High thermoelectric figure-of-merit in Sb2Te3/Ag2Te bulk composites as Pb-free p-type thermoelectric materials
Authors: Lee Min Ho , Kim Ka-Ryeong , Rhyee Jong-Soo , Park Su-Dong , Snyder G. Jeffrey
Published: August 2015

Sb2Te3/Ag2Te (ST/AT) composites with ST/AT molar ratios of 1/1, 2/1, 4/1, 8/1, 16/1, and 32/1 were synthesized, and high ZT values were achieved compared with other Pb-free p-type chalcogenide thermoelectric materials.
High efficiency blue fluorescent organic light-emitting diodes using a conventional blue fluorescent emitter
Authors: Lee In Ho , Song Wook , Lee Jun Yeob , Hwang Seok-Ho
Published: August 2015

High efficiency blue fluorescent organic light-emitting diodes were developed by using a blue delayed fluorescent emitter as a sensitizer.
Multifunctional responsive fibers produced by dual liquid crystal core electrospinning
Authors: Kye YooMee , Kim Changsoon , Lagerwall Jan
Published: August 2015

Multifunctional responsive fibers are produced by dual-core coaxial electrospinning, with distinctly different liquid crystals in adjacent core flows.
Morphology-performance relationships in polymer/fullerene blends probed by complementary characterisation techniques – effects of nanowire formation and subsequent thermal annealing
Authors: Kim Jong Soo , Wood Sebastian , Shoaee Safa , Spencer Steve J. , Castro Fernando A. , Tsoi Wing Chung , Murphy Craig E. , Sim Myungsun , Cho Kilwon , Durrant James R. , Kim Ji-Seon
Published: August 2015

Polymer nanowires are used to form organic solar cells, and the development of the thin film morphology during thermal annealing is characterised in detail.
Properties modulation of organic semi-conductors based on a donor-spiro-acceptor (D-spiro-A) molecular design: new host materials for efficient sky-blue PhOLEDs
Authors: Romain Maxime , Tondelier Denis , Jeannin Olivier , Geffroy Bernard , Rault-Berthelot Joëlle , Poriel Cyril
Published: August 2015

Four high triplet organic semi-conductors based on the donor-spiro-acceptor design (D-spiro-A) have been synthesized.
Influence of fluorination in π-extended backbone polydiketopyrrolopyrroles on charge carrier mobility and depth-dependent molecular alignment
Authors: Mueller C. J. , Gann E. , McNeill C. R. , Thelakkat M.
Published: August 2015

The degree of fluorination in π-extended polydiketopyrrolopyrroles is correlated with semiconductor properties in transistors and an improved molecular alignment in thin films using depth-dependent grazing incidence X-ray scattering.
Suppression of Fatigue Crack Propagation of Duralumin by Cavitation Peening
Authors: Soyama Hitoshi , Kumagai Naoki , Takakuwa Osamu , Takeo Fumio
Published: August 2015

It was demonstrated in the present paper that cavitation peening which is one of the mechanical surface modification technique can suppress fatigue crack propagation in duralumin. The impacts produced when cavitation bubble collapses can be utilised for the mechanical surface modification technique in the same way as laser peening and shot peening, which is called “cavitation peening”. Cavitation peening employing a cavitating jet in water was used to treat the specimen made of duralumin Japanese Industrial Standards JIS A2017‐T3. After introducing a notch, fatigue test was conducted by a load‐controlled plate bending fatigue tester, which has been originally developed. The fatigue crack propagation behavior was evaluated and the relationship between the fatigue crack propagation rate versus stress intensity factor range was obtained. From the results, the fatigue crack propagation rate was drastically reduced by cavitation peening and the fatigue life of duralumin plate was extended 4.2 times by cavitation peening. In addition, the fatigue crack propagation can be suppressed by 88% in the stable crack propagation stage by cavitation peening.
Nevoid Basal Cell Carcinoma Syndrome: A Long-Term Study in a Family
Authors: de Santana Santos Thiago , Vajgel André , Martins-Filho Paulo Ricardo Saquete , de Albuquerque Maranhao Filho AlmirWalter , De Holanda Vasconcellos Ricardo José , Frota Riedel , Filho José Rodrigues Laureano
Published: August 2015

We present a family case series with 10 individuals having nevoid basal cell carcinoma syndrome (NBCCS) with a 10-year follow-up. All articles published in the literature between 1967 and 2011 on familial Gorlin-Goltz syndrome in any language were surveyed to determine the mapping of cases per country of occurrence of this disease. All patients in the present series were presented with calcification of the falx cerebri, mild hypertelorism, and frontal bossing. Odontogenic keratocystic tumors, palmar and plantar pits, and multiple basal cell carcinomas occurred in 90, 40, and 20%, respectively, of the patients. One of the patients died of skin cancer. Diagnosis of odontogenic keratocyst tumors was confirmed by histopathological examination. NBCCS is a rare autosomal dominant cancer predisposition syndrome; it is important to recognize it when a patient has multiple odontogenic keratocyst tumors because life-long monitoring is essential for patient management.
Allometric scaling, size distribution and pattern formation of natural cities
Authors: Li Xintong , Wang Xinran , Zhang Jiang , Wu Lingfei
Published: August 2015

There has been a strong interest in more cogent definitions on economies of scale to reveal general urban growth laws and to develop urban performance metrics. Unstructured data, including satellite images, will provide us with new sources to do so by defining cities as aggregates of human activities. Such a uniform definition on the basis of nighttime light clusters is more consistent and economically meaningful than administrative or official boundaries. In comparison with patterns of city systems found in traditional census data, we examined the allometric scaling, size distribution and fractal geometry of natural cities. It can be concluded from our empirical analysis on regional, country and continental scales that a super-linear scaling between lightness and area with a stable exponent across different low light threshold levels generally holds for natural cities. But Zipf’s Law does not always apply over the whole range of lightness thresholds. Furthermore, we build a model based on the simple geometric matching mechanism to reproduce the self-organized formation process of nighttime light patterns. The statistical properties including allometries, size distributions and fractal geometries generated by our model are in good agreement with empirical evidence. These findings have profound implications for understanding the effects of simple aggregation behaviour in primitive stages of city formation and the urbanization process.
Reference Correlation of the Viscosity of Toluene from the Triple Point to 675 K and up to 500 MPa
Authors: Avgeri S. , Assael M. J. , Huber M. L. , Perkins R. A.
Published: August 2015

This paper contains new, representative reference equations for the viscosity of toluene. The equations are based in part upon a body of experimental data that have been critically assessed for internal consistency and for agreement with theory whenever possible. The correlations are valid from the triple point (178.0 K) to 675 K, and at pressures up to 500 MPa. The estimated uncertainty at a 95% confidence level varies depending on the region of temperature and pressure from a low of 0.3% for the low-density gas at temperatures from 305 to 640 K at pressures to 0.3 MPa (essentially the uncertainty of the best experimental data) to 0.7% for the saturated liquid at temperatures from 263 to 373 K, to 5% for the low-temperature liquid from 187 to 210 K at pressures to 15 MPa.
Controlling drop bouncing using surfaces with gradient features
Authors: Liu Yahua , Whyman Gene , Bormashenko Edward , Hao Chonglei , Wang Zuankai
Published: August 2015

Drop hitting on superhydrophobic surfaces usually undergoes spreading and retraction stages before its complete rebound and there exists a minimum amount of time for the spreading and retraction processes. Impressively, it was recently shown that the so-called contact time can be significantly reduced by engineering surfaces with millimeter-scale tapered post arrays that allow the impinging drop to leave the surfaces in a pancake shape at the end of lateral spreading (pancake bouncing). Despite exciting progress, it remains elusive to rationally control the contact time and quantitatively predict the critical Weber number for the occurrence of pancake bouncing. Here, we experimentally demonstrated that the drop bouncing is intricately modulated by the surface morphology. Under the same centre-to-centre post spacing, surfaces with a larger apex angle could give rise to more robust pancake bouncing, which is characterized by significant contact time reduction, smaller critical Weber number, and wider Weber number range. We also developed simple harmonic spring models and theoretically revealed the dependence of timescales associated with the impinging drop and the critical Weber number for pancake bouncing on the surface morphology. The insights learned from this work will allow us to rationally design various surfaces for many practical applications.
Tunable surface plasmon instability leading to emission of radiation
Authors: Gumbs Godfrey , Iurov Andrii , Huang Danhong , Pan Wei
Published: August 2015

We propose a new approach for energy conversion from a dc electric field to tunable terahertz emission based on hybrid semiconductors by combining two-dimensional (2D) crystalline layers and a thick conducting material with possible applications for chemical analysis, security scanning, medical (single-molecule) imaging, and telecommunications. The hybrid nano-structure may consist of a single or pair of sheets of graphene, silicene, or a 2D electron gas. When an electric current is passed through a 2D layer, we discover that two low-energy plasmon branches exhibit a characteristic loop in their dispersion before they merge into an unstable region beyond a critical wave vector qc. This finite qc gives rise to a wavenumber cutoff in the emission dispersion of the surface plasmon induced instability and emission of radiation (spiler). However, there is no instability for a single driven layer far from the conductor, and the instability of an isolated pair of 2D layers occurs without a wavenumber cutoff. The wavenumber cutoff is found to depend on the conductor electron density, layer separation, distances of layers from the conductor surface, and the driving-current strength.
A spectroelectrochemical cell for ultrafast two-dimensional infrared spectroscopy
Authors: El Khoury Youssef , Van Wilderen Luuk J. G. W. , Vogt Tim , Winter Ernst , Bredenbeck Jens
Published: August 2015

A spectroelectrochemical cell has been designed to combine electrochemistry and ultrafast two-dimensional infrared (2D-IR) spectroscopy, which is a powerful tool to extract structure and dynamics information on the femtosecond to picosecond time scale. Our design is based on a gold mirror with the dual role of performing electrochemistry and reflecting IR light. To provide the high optical surface quality required for laser spectroscopy, the gold surface is made by electron beam evaporation on a glass substrate. Electrochemical cycling facilitates in situ collection of ultrafast dynamics of redox-active molecules by means of 2D-IR. The IR beams are operated in reflection mode so that they travel twice through the sample, i.e., the signal size is doubled. This methodology is optimal for small sample volumes and successfully tested with the ferricyanide/ferrocyanide redox system of which the corresponding electrochemically induced 2D-IR difference spectrum is reported.
Effects of stacking disorder on thermal conductivity of cubic ice
Authors: Johari G. P. , Andersson Ove
Published: August 2015

Cubic ice is said to have stacking disorder when the H2O sequences in its structure (space group Fd3̄m) are interlaced with hexagonal ice (space group P63/mmc) sequences, known as stacking faults. Diffraction methods have shown that the extent of this disorder varies in samples made by different methods, thermal history, and the temperature T, but other physical properties of cubic and hexagonal ices barely differ. We had found that at 160 K, the thermal conductivity, κ, of cubic ice is ∼20% less than that of hexagonal ice, and this difference varies for cubic ice samples prepared by different methods and/or subjected to different thermal history. After reviewing the methods of forming cubic ice, we report an investigation of the effects of stacking disorder and other features by using new data, and by analyzing our previous data on the dependence of κ on T and on the pressure. We conclude that the lower κ of cubic ice and its weaker T-dependence is due mainly to stacking disorder and small crystal sizes. On in situ heating at 20–50 MPa pressure, κ increases and cubic ice irreversibly transforms more sharply to ice Ih, and at a higher T of ∼220 K, than it does in ex situ studies. Cooling and heating between 115 and 130 K at 0.1 K min−1 rate yield the same κ value, indicating that the state of cubic ice in these conditions does not change with time and T. The increase in κ of cubic ice observed on heat-annealing before its conversion to hexagonal ice is attributed to the loss of stacking faults and other types of disorders, and to grain growth. After discussing the consequences of our findings on other properties, we suggest that detailed studies of variation of a given property of cubic ice with the fraction of stacking faults in its structure may reveal more about the effect of this disorder. A similar disorder may occur in the mono-layers of H2O adsorbed on a substrate, in bulk materials comprised of two dimensional layers, in diamond and in Zirconium and in numerous other crystals.
Truncation-based energy weighting string method for efficiently resolving small energy barriers
Authors: Carilli Michael F. , Delaney Kris T. , Fredrickson Glenn H.
Published: August 2015

The string method is a useful numerical technique for resolving minimum energy paths in rare-event barrier-crossing problems. However, when applied to systems with relatively small energy barriers, the string method becomes inconvenient since many images trace out physically uninteresting regions where the barrier has already been crossed and recrossing is unlikely. Energy weighting alleviates this difficulty to an extent, but typical implementations still require the string’s endpoints to evolve to stable states that may be far from the barrier, and deciding upon a suitable energy weighting scheme can be an iterative process dependent on both the application and the number of images used. A second difficulty arises when treating nucleation problems: for later images along the string, the nucleus grows to fill the computational domain. These later images are unphysical due to confinement effects and must be discarded. In both cases, computational resources associated with unphysical or uninteresting images are wasted. We present a new energy weighting scheme that eliminates all of the above difficulties by actively truncating the string as it evolves and forcing all images, including the endpoints, to remain within and cover uniformly a desired barrier region. The calculation can proceed in one step without iterating on strategy, requiring only an estimate of an energy value below which images become uninteresting.
Kinetic theory of dust ion acoustic waves in a kappa-distributed plasma
Authors: Baluku T. K. , Hellberg M. A.
Published: August 2015

Using a kinetic theory approach, dust ion acoustic (DIA) waves are investigated in an unmagnetized collisionless plasma with kappa-distributed electrons and ions, and Maxwellian dust grains of constant charge. Both analytical and numerical results, the latter following from the full solution of the associated dispersion relation, are presented, and a comparison is made. The effects of the ion and electron spectral indices, as well as the species' density (ne/ni) and temperature (Te/Ti) ratios, on the dispersion and damping of the waves are considered. In the long wavelength regime, increases in both the electron spectral index (κe) and the dust density fraction (reduced f=ne/ni) lead to an increase in phase velocity. The range in wavelength over which modes are weakly damped increases with an increase in Te/Ti. However, the ion spectral index, κi, does not have a significant effect on the dispersion or damping of DIA waves.
R-matrix and Mickelsson algebras for orthosymplectic quantum groups
Authors: Ashton Thomas , Mudrov Andrey
Published: August 2015

Let 𝔤 be a complex orthogonal or symplectic Lie algebra and 𝔤′ ⊂ 𝔤 the Lie subalgebra of rank rk 𝔤′ = rk 𝔤 − 1 of the same type. We give an explicit construction of generators of the Mickelsson algebra Zq(𝔤, 𝔤′) in terms of Chevalley generators via the R-matrix of Uq(𝔤).
Non-contact method for characterization of small size thermoelectric modules
Authors: Manno Michael , Yang Bao , Bar-Cohen Avram
Published: August 2015

Conventional techniques for characterization of thermoelectric performance require bringing measurement equipment into direct contact with the thermoelectric device, which is increasingly error prone as device size decreases. Therefore, the novel work presented here describes a non-contact technique, capable of accurately measuring the maximum ΔT and maximum heat pumping of mini to micro sized thin film thermoelectric coolers. The non-contact characterization method eliminates the measurement errors associated with using thermocouples and traditional heat flux sensors to test small samples and large heat fluxes. Using the non-contact approach, an infrared camera, rather than thermocouples, measures the temperature of the hot and cold sides of the device to determine the device ΔT and a laser is used to heat to the cold side of the thermoelectric module to characterize its heat pumping capacity. As a demonstration of the general applicability of the non-contact characterization technique, testing of a thin film thermoelectric module is presented and the results agree well with those published in the literature.
Comparison of vortex identification criteria for planar velocity fields in wall turbulence
Authors: Chen Qigang , Zhong Qiang , Qi Meilan , Wang Xingkui
Published: August 2015

This study derives and compares vortex identification methods for detecting vortices in planar velocity fields. Two-dimensional (2D) forms of the commonly used Δ, Q, λci, and λ2 criteria are derived in detail based on the 2D counterpart of the full velocity gradient tensor. These four criteria are compared mathematically and experimentally in the case of using zero thresholds. The results show that while all methods are capable of extracting strong vortices, their efficiencies in identifying weaker vortices are not necessarily the same. The Δ and λci criteria impose the least requirements on the identified structures and extract the most number of vortices, and the λ2 criterion is the most restrictive one and tends to discard the weakest vortices. However, non-zero thresholds are generally necessary for applying vortex identification criteria in real turbulent flows, and normalizing the vortex indicators with their root mean squares is needed to enable the selection of universal threshold for vortices residing at different wall-normal positions in wall turbulence. The introduction of threshold makes the four vortex identification criteria equally efficacious, and equivalent thresholds are proposed to facilitate quantitative comparison of results based on different criteria in wall turbulence.
Thermoelectricity and thermodiffusion in charged colloids
Authors: Huang B. T. , Roger M. , Bonetti M. , Salez T. J. , Wiertel-Gasquet C. , Dubois E. , Cabreira Gomes R. , Demouchy G. , Mériguet G. , Peyre V. , Kouyaté M. , Filomeno C. L. , Depeyrot J. , Tourinho F. A. , Perzynski R. , Nakamae S.
Published: August 2015

The Seebeck and Soret coefficients of ionically stabilized suspension of maghemite nanoparticles in dimethyl sulfoxide are experimentally studied as a function of nanoparticle volume fraction. In the presence of a temperature gradient, the charged colloidal nanoparticles experience both thermal drift due to their interactions with the solvent and electric forces proportional to the internal thermoelectric field. The resulting thermodiffusion of nanoparticles is observed through forced Rayleigh scattering measurements, while the thermoelectric field is accessed through voltage measurements in a thermocell. Both techniques provide independent estimates of nanoparticle’s entropy of transfer as high as 82 meV K−1. Such a property may be used to improve the thermoelectric coefficients in liquid thermocells.
Microsolvation of sodium acetate in water: Anion photoelectron spectroscopy and ab initio calculations
Authors: Zhang Wen-Jing , Hou Gao-Lei , Wang Peng , Xu Hong-Guang , Feng Gang , Xu Xi-Ling , Zheng Wei-Jun
Published: August 2015

To understand the microsolvation of sodium acetate (CH3COONa, NaOAc) in water, we studied NaOAc(H2O)n− (n = 0–3) clusters by photoelectron spectroscopy. We also investigated the structures of NaOAc(H2O)n− (n = 0–5) anions and NaOAc(H2O)n (n = 0–7) neutrals by quantum chemistry calculations. By comparing the theoretical results with the photoelectron experiment, the most probable structures of NaOAc(H2O)n−/0 (n = 0–3) were determined. The study also shows that, with increasing n, the solvent-separated ion pair (SSIP) structures of NaOAc(H2O)n− anions become nearly energetically degenerate with the contact ion pair (CIP) structures at n = 5, while the SSIP structures of the neutral NaOAc(H2O)n clusters appear at n = 6 and become dominant at n = 7.
Thermodynamics and kinetics of binary nucleation in ideal-gas mixtures
Authors: Alekseechkin Nikolay V.
Published: August 2015

The nonisothermal single-component theory of droplet nucleation [N. V. Alekseechkin, Physica A 412, 186 (2014)] is extended to binary case; the droplet volume V, composition x, and temperature T are the variables of the theory. An approach based on macroscopic kinetics (in contrast to the standard microscopic model of nucleation operating with the probabilities of monomer attachment and detachment) is developed for the droplet evolution and results in the derived droplet motion equations in the space (V, x, T)—equations for V̇≡dV/dt, ẋ, and Ṫ. The work W(V, x, T) of the droplet formation is obtained in the vicinity of the saddle point as a quadratic form with diagonal matrix. Also, the problem of generalizing the single-component Kelvin equation for the equilibrium vapor pressure to binary case is solved; it is presented here as a problem of integrability of a Pfaffian equation. The equation for Ṫ is shown to be the first law of thermodynamics for the droplet, which is a consequence of Onsager’s reciprocal relations and the linked-fluxes concept. As an example of ideal solution for demonstrative numerical calculations, the o-xylene-m-xylene system is employed. Both nonisothermal and enrichment effects are shown to exist; the mean steady-state overheat of droplets and their mean steady-state enrichment are calculated with the help of the 3D distribution function. Some qualitative peculiarities of the nucleation thermodynamics and kinetics in the water-sulfuric acid system are considered in the model of regular solution. It is shown that there is a small kinetic parameter in the theory due to the small amount of the acid in the vapor and, as a consequence, the nucleation process is isothermal.
Measurement of eddy-current distribution in the vacuum vessel of the Sino-UNIted Spherical Tokamak
Authors: Li G. , Tan Y. , Liu Y. Q.
Published: August 2015

Eddy currents have an important effect on tokamak plasma equilibrium and control of magneto hydrodynamic activity. The vacuum vessel of the Sino-UNIted Spherical Tokamak is separated into two hemispherical sections by a toroidal insulating barrier. Consequently, the characteristics of eddy currents are more complex than those found in a standard tokamak. Thus, it is necessary to measure and analyze the eddy-current distribution. In this study, we propose an experimental method for measuring the eddy-current distribution in a vacuum vessel. By placing a flexible printed circuit board with magnetic probes onto the external surface of the vacuum vessel to measure the magnetic field parallel to the surface and then subtracting the magnetic field generated by the vertical-field coils, the magnetic field due to the eddy current can be obtained, and its distribution can be determined. We successfully applied this method to the Sino-UNIted Spherical Tokamak, and thus, we obtained the eddy-current distribution despite the presence of the magnetic field generated by the external coils.
Entire solutions of time periodic bistable reaction-advection-diffusion equations in infinite cylinders
Authors: Sheng Wei-Jie , Wang Jia-Bing
Published: August 2015

This paper is concerned with the existence and some qualitative properties of entire solutions for a reaction-advection-diffusion equation in infinite cylinders with time periodic bistable nonlinearity. Here, an entire solution means a solution defined in the whole space and for all time t ∈ ℝ. By the comparison principle coupled with the supersolution and subsolution technique, it is proved that there exists an entire solution. Furthermore, it is shown that such an entire solution is unique and Liapunov stable. Unlike the reaction-diffusion equation without advection, the lack of symmetry between increasing and decreasing traveling fronts caused by the advection affects the construction of supersolutions and subsolutions.
A continuous sampling scheme for edge illumination x-ray phase contrast imaging
Authors: Hagen C. K. , Coan P. , Bravin A. , Olivo A. , Diemoz P. C.
Published: August 2015

We discuss an alternative acquisition scheme for edge illumination (EI) x-ray phase contrast imaging based on a continuous scan of the object and compare its performance to that of a previously used scheme, which involved scanning the object in discrete steps rather than continuously. By simulating signals for both continuous and discrete methods under realistic experimental conditions, the effect of the spatial sampling rate is analysed with respect to metrics such as image contrast and accuracy of the retrieved phase shift. Experimental results confirm the theoretical predictions. Despite being limited to a specific example, the results indicate that continuous schemes present advantageous features compared to discrete ones. Not only can they be used to speed up the acquisition but they also prove superior in terms of accurate phase retrieval. The theory and experimental results provided in this study will guide the design of future EI experiments through the implementation of optimized acquisition schemes and sampling rates.
Time-resolved study of the extreme-ultraviolet emission and plasma dynamics of a sub-Joule, fast capillary discharge
Authors: Valenzuela J. C. , Wyndham E. S. , Favre M.
Published: August 2015

In this work, we discuss experimental observations on the dynamics of a fast, low energy capillary discharge when operated in argon and its properties as an intense source of extreme-ultraviolet (EUV) radiation. The discharge pre-ionization and self-triggering were accomplished by the use of the hollow cathode effect. This allowed a compact size and low inductance discharge with multi-kA current level and a quarter-period of ∼10 ns at sub-Joule energy level. We used the novel moiré and schlieren diagnostics with a 12 ps laser to obtain the time evolution of the line electron density and to study the plasma dynamics. EUV spectroscopy and filtered diodes were also implemented to estimate the plasma temperature and density throughout the evolution of the discharge. EUV source size was measured by using a filtered slit-wire camera. We observed that EUV emission starts from a compressed plasma on axis during the second quarter-period of the current and continues until the fifth quarter-period. Ionization levels from Ar VII to X were observed. By comparing the EUV emission spectra with synthetic spectra, we found that at the onset of emission (∼7 ns), the plasma is well fitted by a single Maxwellian electron distribution function with Te ∼ 12 eV and ne ∼ 1017 cm−3. Close to peak emission (∼13 ns), plasma temperature and density increase to ∼20 eV and ne ∼ 1018 cm−3, respectively. However, in order to successfully match the experimental data, a two component electron distribution function was necessary. Later in time, a smaller fraction in the high energy component and higher temperature suggests homogenization of the plasma. The moiré and schlieren diagnostics showed multiple radial compression-waves merging on axis throughout the discharge; they are an important heating mechanism that leads to a period of severe turbulence at peak EUV emission. It was also observed that emission ceases when the axial maximum of the electron density collapses.
Double-pinned magnetic tunnel junction sensors with spin-valve-like sensing layers
Authors: Yuan Z. H. , Huang L. , Feng J. F. , Wen Z. C. , Li D. L. , Han X. F. , Nakano Takafumi , Yu T. , Naganuma Hiroshi
Published: August 2015

MgO magnetic tunnel junction (MTJ) sensors with spin-valve-like sensing layers of Ir22Mn78 (6)/Ni80Fe20 (tNiFe = 20–70)/Ru (0.9)/Co40Fe40B20 (3) (unit: nm) have been fabricated. A linear field dependence of magnetoresistance for these MTJ sensors was obtained by carrying out a two-step field annealing process. The sensitivity and linear field range can be tuned by varying the thickness of NiFe layer and annealing temperature, and a high sensitivity of 37%/mT has been achieved in the MTJ sensors with 70 nm NiFe at the optimum annealing temperature of 230 °C. Combining the spin-valve-like sensing structure and a soft magnetic NiFe layer, MTJ sensors with relatively wide field sensing range have been achieved and could be promising for showing high sensitivity magnetic field sensing applications.
Investigation about relationships between the symmetries of ferroelectric crystal Ca0.28Ba0.72Nb2O6 and second-harmonic patterns
Authors: Xu Tianxiang , Yu Haohai , Zhang Huaijin , Wang Jiyang
Published: August 2015

The broadband quasi-phase matching (QPM) process in a uniaxial ferroelectric crystal Ca0.28Ba0.72Nb2O6 (CBN-28) was demonstrated with the second-harmonic wavelength range from 450 nm to 650 nm, and the relationship between the symmetries of CBN-28 and the second-harmonic patterns was experimentally and theoretically investigated based on the random anti-parallel domains in the crystal and QPM conditions. The dependences of frequency-doubled patterns on the wavelength and anisotropy of the nonlinear crystal were also studied, and the frequency-doubled photons were found to be trapped on circles. By analyzing the light-matter interacting Hamiltonians, the trapping force for second-harmonic photons was found to be centripetal and tunable by the fundamental lasers, and the variation tendencies of the rotational velocity of second-harmonic generation photons could also be predicated. The results indicate that the CBN-28 ferroelectric crystal is a promising nonlinear optical material for the generation of broadband frequency-doubled waves, and the analysis on centripetal force based on the interaction Hamiltonians may provide a novel recognition for the investigation of QPM process to be further studied.
Magnetic anisotropy of La2Co7
Authors: Kuz'min M. D. , Skokov K. P. , Radulov I. , Schwöbel C. A. , Foro S. , Donner W. , Werwiński M. , Rusz J. , Delczeg-Czirjak E. , Gutfleisch O.
Published: August 2015

A magnetization study of a La2Co7 single crystal has obtained the following anisotropy constants: K1 = 1.4 MJ/m3 and K2 = 0.02 MJ/m3 (at room temperature). The corresponding anisotropy field is 6.7 T; an earlier report of a much higher value (17 T) has not been confirmed. A significant (10%) magnetization anisotropy has been observed. Density-functional calculations are in qualitative agreement with the new data.