bluuebunny/crossref_metadata_2025 huggingface dataset:
Revealing nanocomposite filler structures by swelling and small-angle X-ray scattering
Authors: Baeza Guilhem P. , Genix Anne-Caroline , Paupy-Peyronnet Nathalie , Degrandcourt Christophe , Couty Marc , Oberdisse Julian
Published: September 2015

Polymer nanocomposites are used widely, mainly for the industrial application of car tyres. The rheological behavior of such nanocomposites depends in a crucial way on the dispersion of the hard filler particles – typically silica nanoparticles embedded in a soft polymer matrix. It is thus important to assess the filler structure, which may be quite difficult for aggregates of nanoparticles of high polydispersity, and with strong interactions at high loading. This has been achieved recently using a coupled TEM/SAXS structural model describing the filler microstructure of simplified industrial nanocomposites with grafted or ungrafted silica of high structural disorder. Here, we present an original method capable of reducing inter-aggregate interactions by swelling of nanocomposites, diluting the filler to low-volume fractions. Note that this is impossible to reach by solid mixing due to the large differences in viscoelasticity between the composite and the pure polymer. By combining matrix crosslinking, swelling in a good monomer solvent, and post-polymerization of these monomers, it is shown that it is possible to separate the filler into small aggregates. The latter have then been characterized by electron microscopy and small-angle X-ray scattering, confirming the conclusions of the above mentioned TEM-SAXS structural model applied directly to the highly loaded cases.
β-Cyclodextrin/IBX in water: highly facile biomimetic one pot deprotection of THP/MOM/Ac/Ts ethers and concomitant oxidative cleavage of chalcone epoxides and oxidative dehydrogenation of alcohols
Authors: Kumar Sumit , Ahmed Naseem
Published: September 2015

A mild and efficient one-pot deprotection of THP/MOM/Ac/Ts ethers, and concomitant oxidative cleavage of epoxides and oxidative dehydrogenation of alcohols using β-cyclodextrin/IBX in water has been developed.
Chiral discrimination of β-telluride carboxylic acids by NMR spectroscopy
Authors: Silva Marcio S. , Pietrobom Daniel
Published: September 2015

A simple and effective procedure for the chiral discrimination of β-telluride carboxylic acids by1H and125Te NMR spectroscopy is presented.
Magnetic nanoparticle-conjugated polymeric micelles for combined hyperthermia and chemotherapy
Authors: Kim Hyun-Chul , Kim Eunjoo , Jeong Sang Won , Ha Tae-Lin , Park Sang-Im , Lee Se Guen , Lee Sung Jun , Lee Seung Woo
Published: September 2015

The cytotoxicity of magnetic nanoparticles-conjugated polymeric micelles encapsulated with an anticancer drug on cancer cells was enhanced by the synergistic effect of heat and the rapid release of the drug under an alternating magnetic field.
Location-specific nanoplasmonic sensing of biomolecular binding to lipid membranes with negative curvature
Authors: Junesch Juliane , Emilsson Gustav , Xiong Kunli , Kumar Shailabh , Sannomiya Takumi , Pace Hudson , Vörös Janos , Oh Sang-Hyun , Bally Marta , Dahlin Andreas B.
Published: September 2015

Location-specific nanoplasmonic sensing by monitoring different spectral parameters is used to show how norovirus accumulate in membrane invaginations.
Understanding the electric field control of the electronic and optical properties of strongly-coupled multi-layered quantum dot molecules
Authors: Usman Muhammad
Published: September 2015

An electric field transforms molecular states to atomic states.
Recent advances in the ruthenium-catalyzed hydroarylation of alkynes with aromatics: synthesis of trisubstituted alkenes
Authors: Manikandan Rajendran , Jeganmohan Masilamani
Published: September 2015

The hydroarylation of alkynes with amide, azole, carbamate, phosphine oxide, amine, acetyl, sulfoxide and sulphur substituted aromatics in the presence of a ruthenium catalyst via chelation-assisted C–H bond activation is discussed.
Production of chiral compounds using immobilized cells as a source of biocatalysts
Authors: Kisukuri Camila M. , Andrade Leandro H.
Published: September 2015

The main aspects about production of chiral compounds using immobilized cells as source of biocatalysts were presented.
Cu-mediated nitrogen atom transfer via CN bond cleavage
Authors: Liu Lixin , Dong Jianyu , Zhang Yaxing , Zhou Yongbo , Yin Shuang-Feng
Published: September 2015

A nitrogen atom transfer to organic molecules affording aryl nitriles via Cu-mediated C–N triple bond cleavage is firstly developed.
A novel route for the synthesis of alkanes from glycerol in a two step process using a Pd/SBA-15 catalyst
Authors: Udayakumar V. , Pandurangan A.
Published: September 2015

Glycerol is produced as a valuable by-product in the transesterification of fatty acids, but it cannot be used directly as a fuel additive.
Facile and green cinchonidine-assisted synthesis of ultrafine and well-dispersed palladium nanoparticles supported on activated carbon with high catalytic performance
Authors: Tran Si Bui Trung , Kim Yeonwoo , Kim Sehun , Lee Hangil
Published: September 2015

We report the facile and green synthesis of activated carbon-supported palladium (Pd/AC) containing homogeneously dispersed Pd nanoparticles (Pd NPs) by using eco-friendly and naturally available cinchonidine (CD) as the capping agent.
Enhanced reductive transformation of 2,4-dinitroanisole in a anaerobic system: the key role of zero valent iron
Authors: Ou Changjin , Zhang Shuai , Liu Jianguo , Shen Jinyou , Han Weiqing , Sun Xiuyun , Li Jiansheng , Wang Lianjun
Published: September 2015

Accelerated reduction of typical multi-substituted nitroaromatic compounds (NACs),i.e., 2,4-dinitroanisole (DNAN), was achieved in an anaerobic system coupled with zero valent iron (ZVI), with the underlying role of ZVI in this process elucidated.
Interaction of bisbenzimidazole-substituted carbazole derivatives with G-quadruplexes and living cells
Authors: Wei Yongbiao , Zhang Xin , Wang Linlin , Liu Ying , Bing Tao , Liu Xiangjun , Shangguan Dihua
Published: September 2015

Bisbenzimidazole-substituted carbazole derivatives selectively bind to parallel G-quadruplexes. They enter living cells and exhibit different cytotoxicities depending on their side chains.
A new facile strategy for higher loading of silver nanoparticles onto silica for efficient catalytic reduction of 4-nitrophenol
Authors: Muthuchamy N. , Gopalan A. , Lee Kwang-Pill
Published: September 2015

The facile route to higher loading of silver nanoparticles onto a silica support is useful for large-scale synthesis of efficient silver supported catalysts.
Bioinspired preparation of monolithic ordered mesoporous silica for enrichment of endogenous peptides
Authors: Zhu Gang-Tian , Chen Xi , He Xiao-Mei , Zhang Zheng , Li Xiao-Shui , Yuan Bi-Feng , Feng Yu-Qi
Published: September 2015

Monolithic ordered mesoporous silica with various sizes and shapes were prepared in one-pot modified Stöber synthesis using pomelo peel and CTAB as dual templates, and applied as packing adsorbents for peptide enrichment.
Graphene oxide hydrogel improved sensitivity in one-dimensional photonic crystals for detection of beta-glucan
Authors: Ren Jiaoyu , Xuan Hongyun , Liu Cihui , Yao Chong , Zhu Yanxi , Liu Xuefan , Ge Liqin
Published: September 2015

This study establishes a new approach to quantify beta-glucan in oats by combining the dye Congo red with 1DPhCs with a PANI defect.
A highly selective chemosensor for naked-eye sensing of nanomolar Cu(ii) in an aqueous medium
Authors: Qian Yaao , Cao Li , Jia Chunman , Boamah Peter Osei , Yang Qiuyun , Liu Chunling , Huang Yan , Zhang Qi
Published: September 2015

A colorimetric chemosensor was developed for the sensitive detection and quantification of Cu2+with a short response time in an aqueous medium.
Supporting of mixed ZnS–NiS semiconductors onto clinoptilolite nano-particles to improve its activity in photodegradation of 2-nitrotoluene
Authors: Mohammadyari Parisa , Nezamzadeh-Ejhieh Alireza
Published: September 2015

Migration of photo-generated electrons from the NiS-Cb level to ZnS-Cb prevents e–h recombination, causing a significant increase in photocatalytic activity.
Solvent assisted structural diversity: supramolecular sheet and double helix of a short aromatic γ-peptide
Authors: Sarkar Rajib , Debnath Mintu , Maji Krishnendu , Haldar Debasish
Published: September 2015

Solvent interaction has a significant effect on the molecular motions, folding and self-assembly of short aromatic γ-peptides that leads to a change in initial helical conformation.
A theoretical study on borenium ion affinities toward ammonia, formaldehyde and chloride anions
Authors: Stojanović Milovan , Baranac-Stojanović Marija
Published: September 2015

The effect of R/R′ and L on borenium ion affinities toward NH3, HCHO and Cl− has been evaluated by DFT calculations and rationalized on the basis of an energy decomposition analysis.
The effect of the prefrozen process on properties of a chitosan/hydroxyapatite/poly(methyl methacrylate) composite prepared by freeze drying method used for bone tissue engineering
Authors: Zhang Xueqin , Zhang Yuxuan , Ma Guiping , Yang Dongzhi , Nie Jun
Published: September 2015

The process of different prefrozen methods to prepare a CS–HA/PMMA scaffold for bone tissue engineering.
Rapid microwave synthesis of white light emitting magic sized nano clusters of CdSe: role of oleic acid
Authors: Jadhav Aditi A. , More Priyesh V. , Khanna Pawan K.
Published: September 2015

A rapid green one-pot microwave synthesis of magic sized nano clusters of CdSe is presented using cycloalkeno-1,2,3-selenadiazoles as the Se source. The role of oleic acid in the cluster formation is discussed, which emit white light when illuminated with 365 nm light.
Navigating in chromone chemical space: discovery of novel and distinct A3adenosine receptor ligands
Authors: Cagide F. , Gaspar A. , Reis J. , Chavarria D. , Vilar S. , Hripcsak G. , Uriarte E. , Kachler S. , Klotz K. N. , Borges F.
Published: September 2015

One of the major hurdles in the development of effective drugs targeting GPCRs is finding ligands selective for a specific receptor subtype. Here we describe a potent and selective hormone-basedhA3AR ligand (Kiof 167 nM) with a remarkable selectivity.
Influence of Ce2O3 and CeO2 promoters on Pd/MgO catalysts in the dry-reforming of methane
Authors: Al-Doghachi Faris A. J. , Rashid Umer , Zainal Zulkarnain , Saiman Mohd Izham , Taufiq Yap Yun Hin
Published: September 2015

In this study, the conversion of methane and CO2 to synthesis gas using dry reforming over Pd/MgO catalysts using different concentrations of Ce3+ and Ce4+ was investigated.
Lead selenide quantum dots and carbon dots amplify solar conversion capability of a TiO2/CdS photoanode
Authors: Kokal Ramesh K. , Naresh Kumar P. , Deepa Melepurath , Srivastava Avanish Kumar
Published: September 2015

An integrated approach involving the use of visible light absorbing CdS quantum dots (QDs) and near infrared light harvesting PbSe QDs, along with highly conducting carbon dots (C-dots), resulting in impressive power conversion efficiency (PCE) is presented.
Determination of the shell growth direction during the formation of silica microcapsules by confocal fluorescence microscopy
Authors: van Wijk Judith , Salari Joris W. O. , Meuldijk Jan , Klumperman Bert
Published: September 2015

A novel procedure was developed to determine the direction of silica growth during the formation of a silica shell around aqueous microdroplets in water-in-oil Pickering emulsions, and it was found that the shell grows from the inside to the outside.
Fabrication of biomimetic bundled gel fibres using dynamic microfluidic gelation of phase-separated polymer solutions
Authors: Kim Young-Jin , Takahashi Yuta , Kato Norihiro , Matsunaga Yukiko T.
Published: September 2015

Here, we discuss the fabrication of biomimetic bundle-structured gel fibres using a microfluidic device and the rapid cross-linking of a phase-separated polymer blend solution.
Activation of NF-κB signaling in rare earth neodymium oxide particle-induced acute lung injury
Authors: Wang Suhua , Gao Yanrong , Huang Lihua , Zheng Shanshan , Wang Chunxia , Yu Yanqin , Xie Keqin
Published: September 2015

The activation mechanism of the NF-κB signaling pathway in Nd2O3exposure-induced acute lung inflammation and pneumoconiosis.
Toxicity evaluation and translocation of carboxyl functionalized graphene in Caenorhabditis elegans
Authors: Yang Junnian , Zhao Yunli , Wang Yanwen , Wang Haifang , Wang Dayong
Published: September 2015

G-COOH in the range of mg L−1did not cause toxic effects on both the exposed nematodes and their progeny.
The cytotoxic mechanisms of disulfiram and copper(ii) in cancer cells
Authors: Tawari Patricia Erebi , Wang Zhipeng , Najlah Mohammad , Tsang Chi Wai , Kannappan Vinodh , Liu Peng , McConville Christopher , He Bin , Armesilla Angel L. , Wang Weiguang
Published: September 2015

The anticancer activity of disulfiram (DS) is copper(ii) (Cu)-dependent. This study investigated the anticancer mechanisms of DS/Cu using in vitro cytotoxicity and metabolic kinetic analysis. Our study indicates that DS/Cu targets cancer cells by the combination of two types of actions: (1) instant killing executed by DS/Cu reaction generated reactive oxygen species; (2) delayed cytotoxicity introduced by the end product, DDC-Cu. Nanoencapsulation of DS might shed light on repositioning of DS into cancer treatment.
Building an Inclusive, Accessible, and Responsive Campus at California State University East Bay, 2010-2015
Authors: Woods Dianne Rush , Taylor Sarah , Austin Duke , Beck Julie , Chung Ken , Couch Stephanie , Davis E. Maxwell , Fauth Bryan , Geron Kim , Ireland Dale Katherine , Kupers Eric , Massey Michael S. , Rowley Amy June , Stein Julie , Weiss Jessica
Published: September 2015

California State University East Bay (CSUEB), opened in 1959 with 300 students on one campus. Since then, it has grown to serve over 14,000 students on three campuses. The motto of our university is “Per Aspera Ad Astra”, or “Through Adversity to the Stars”. This is an apt motto given that our university is the most racially and ethnically diverse campus in the continental United States (The Chronicle of Higher Education, 2014), and 61% of our undergraduate students are the first in their families to earn a college degree (Office of Institutional Research, personal communication, March 9, 2015). Our students are also highly diverse in terms of age, ability status, parenting experience, immigration background, sexual orientation, gender, religion, and much more. Though the diversity of our campus provides ample opportunities for faculty, staff, and students to be exposed to multiple perspectives, we have learned that intentional efforts are required to build an inclusive, accessible, and responsive community.

This article describes strategies we have employed over the past five years across three broad areas: (a) support for student learning, engagement, and retention; (b) professional development; and (c) policies around inclusion and access. Preliminary evaluation of these efforts suggests that we have made significant progress in building an inclusive campus that supports student learning, respects all members of the campus community, and facilitates our continuing engagement in this work.
Cultural Competence Needed to Distinguish Disorder from Difference: Beyond Kumbaya
Authors: Crowley Catherine J. , Guest Kristin , Sudler Kenay
Published: September 2015

What does it mean to have true cultural competence as an speech-language pathologist (SLP)? In some areas of practice it may be enough to develop a perspective that values the expectations and identity of our clients and see them as partners in the therapeutic process. But when clinicians are asked to distinguish a language difference from a language disorder, cultural sensitivity is not enough. Rather, in these cases, cultural competence requires knowledge and skills in gathering data about a student's cultural and linguistic background and analyzing the student's language samples from that perspective. This article describes one American Speech-Language-Hearing Association (ASHA)-accredited graduate program in speech-language pathology and its approach to putting students on the path to becoming culturally competent SLPs, including challenges faced along the way. At Teachers College, Columbia University (TC) the program infuses knowledge of bilingualism and multiculturalism throughout the curriculum and offers bilingual students the opportunity to receive New York State certification as bilingual clinicians. Graduate students must demonstrate a deep understanding of the grammar of Standard American English and other varieties of English particularly those spoken in and around New York City. Two recent graduates of this graduate program contribute their perspectives on continuing to develop cultural competence while working with diverse students in New York City public schools.
Students Involvement in Multilingual and Multicultural Community Services
Authors: Tsao Ying-Chiao
Published: September 2015

Promoting cultural competence in serving diverse clients has become critically important across disciplines. Yet, progress has been limited in raising awareness and sensitivity. Tervalon and Murray-Garcia (1998) believed that cultural competence can only be truly achieved through critical self-assessment, recognition of limits, and ongoing acquisition of knowledge (known as “cultural humility”). Teaching cultural humility, and the value associated with it remains a challenging task for many educators. Challenges inherent in such instruction stem from lack of resources/known strategies as well as learner and instructor readiness. Kirk (2007) further indicates that providing feedback on one's integrity could be threatening. In current study, both traditional classroom-based teaching pedagogy and hands-on community engagement were reviewed. To bridge a gap between academic teaching/learning and real world situations, the author proposed service learning as a means to teach cultural humility and empower students with confidence in serving clients from culturally/linguistically diverse backgrounds. To provide a class of 51 students with multicultural and multilingual community service experience, the author partnered with the Tzu-Chi Foundation (an international nonprofit organization). In this article, the results, strengths, and limitations of this service learning project are discussed.
Piezoelectric-driven droplet impact printing with an interchangeable microfluidic cartridge
Authors: Li Baoqing , Fan Jinzhen , Li Jiannan , Chu Jiaru , Pan Tingrui
Published: September 2015

Microfluidic impact printing has been recently introduced, utilizing its nature of simple device architecture, low cost, non-contamination, and scalable multiplexability and high throughput. In this paper, we have introduced an impact-based droplet printing platform utilizing a simple plug-and-play microfluidic cartridge driven by piezoelectric actuators. Such a customizable printing system allows for ultrafine control of droplet volume from picoliters (∼23 pl) to nanoliters (∼10 nl), a 500 fold variation. The high flexibility of droplet generation can be simply achieved by controlling the magnitude of actuation (e.g., driving voltage) and the waveform shape of actuation pulses, in addition to nozzle size restrictions. Detailed printing characterizations on these parameters have been conducted consecutively. A multiplexed impact printing system has been prototyped and demonstrated to provide the functions of single-droplet jetting and droplet multiplexing as well as concentration gradient generation. Moreover, a generic biological assay has also been tested and validated on this printing platform. Therefore, the microfluidic droplet printing system could be of potential value to establish multiplexed micro reactors for high-throughput life science applications.
A dynamic pressure view cell for acoustic stimulation of fluids—Micro-bubble generation and fluid movement in porous media
Authors: Stewart Robert A. , Shaw J. M.
Published: September 2015

The development and baseline operation of an acoustic view cell for observing fluids, and fluid-fluid and fluid-solid interfaces in porous media over the frequency range of 10–5000 Hz is described. This range includes the industrially relevant frequency range 500-5000 Hz that is not covered by existing devices. Pressure waveforms of arbitrary shape are generated in a 17.46 mm ID by 200 mm and 690.5 mm long glass tubes at flow rates up to 200 ml/min using a syringe pump. Peak-to-peak amplitudes exceeding 80 kPa are readily realized at frequencies from 10 to 5000 Hz in bubble free fluids when actuated with 20 Vpp as exemplified using castor oil. At resonant frequencies, peak-to-peak pressure amplitudes exceeding 500 kPa were obtained (castor oil at 2100 Hz when actuated with 20 Vpp). Impacts of vibration on macroscopic liquid-liquid and liquid-vapour interfaces and interface movement are illustrated. Pressure wave transmission and attenuation in a fluid saturated porous medium, randomly packed 250-330 μm spherical silica beads, is also demonstrated. Attenuation differences and frequency shifts in resonant peaks are used to detect the presence and generation of dispersed micro-bubbles (<180 μm diameter), and bubbles within porous media that are not readily visualized. Envisioned applications include assessment of the impacts of vibration on reaction, mass transfer, and flow/flow pattern outcomes. This knowledge will inform laboratory and pilot scale process studies, where nuisance vibrations may affect the interpretation of process outcomes, and large scale or in situ processes in aquifers or hydrocarbon reservoirs where imposed vibration may be deployed to improve aspects of process performance. Future work will include miscible interface observation and quantitative measurements in the bulk and in porous media where the roles of micro-bubbles comprise subjects of special interest.
Synthesis and up-conversion luminescence of Er3+ and Y b3+ codoped nanocrystalline tetra- (KLaP4O12) and pentaphosphates (LaP5O14)
Authors: Marciniak L. , Stefanski M. , Tomala R. , Hreniak D. , Strek W.
Published: September 2015

The up-converting nanocrystals of KLa0.95Er0.05Y bxP4O12 and La0.95−xEr0.05Y bxP5O14 were prepared using co-precipitation method. The spectroscopic properties of these materials were investigated in a function of Y b3+ concentration. The up-conversion emission, power dependence of emission intensities, and the luminescence decay times were investigated. It was found that the green to red and 2H11/2 → 4I15/2 to 4S3/2 → 4I15/2 emission intensity ratio were strongly affected by the Y b3+ concentration. Moreover, the order of up-conversion emission and threshold power rises up with Y b3+ concentration for 4S3/2 → 4I15/2 transition. The luminescence decay time of the 4S3/2 → 4I15/2 emission increases with Y b3+ concentration while the 4F9/2 → 4I15/2 emission is independent of dopant concentration. The influence of the Y b3+ concentration on the up-conversion emission intensities was discussed in terms of concentration dependent hetero looped photon avalanche process. A comparison of the up-conversion properties of KLa0.95Er0.05Y bxP4O12 and La0.95−xEr0.05Y bxP5O14 nanocrystals was presented.
Micromechanical properties of VT1-0 titanium cryorolled to various degrees of strain
Authors: Rusakova A. V. , Lubenets S. V. , Fomenko L. S. , Moskalenko V. A. , Smirnov A. R.
Published: September 2015

Multipass rolling of VT1-0 titanium at a temperature near that of liquid nitrogen to a strain e = −2 resulted in grain refinement from ∼10 μm to ∼35 nm and a nearly twofold increase in microhardness. The microindentation measurements showed that the cryorolled samples had a rather homogeneous structure. An increase in the microhardness with increasing the strain can be described by the modified empirical Voce equation. The grain size dependence of the microhardness in the Hall–Petch coordinates consists of two parts with the slopes kHP1 and kHP2 < kHP1 for the grain size smaller than ∼250 nm. The strong temperature dependence of the microhardness for the investigated samples suggests that their plastic deformation has a thermally activated character. Close values of the thermoactivation parameters presumably indicate a common deformation mechanism in this material placed under an indenter over the entire grain size range.
Existence and multiplicity of solutions for superlinear fractional Schrödinger equations in ℝN
Authors: Zhang Hui , Xu Junxiang , Zhang Fubao
Published: September 2015

In this paper, we are concerned with superlinear fractional Schrödinger equation (−Δ)su + V(x) u = f(x, u), x ∈ ℝN, where f is continuous. When V and f are asymptotically periodic in x, we show the existence of ground states. When V and f are periodic in x, we obtain infinitely many geometrically distinct solutions. The method used here is based on the method of Nehari manifold and Lusternik-Schnirelmann category theory.
On the environmental modes for the generalized Langevin equation
Authors: Kawai Shinnosuke
Published: September 2015

The generalized Langevin equation (GLE) is used widely in molecular science and time series analysis as it offers a convenient low-dimensional description for large systems. There the dynamical effect of the environment interacting with the low-dimensional system is expressed as friction and random force. The present paper aims to investigate explicit dynamical variables to describe the dynamical modes in the environment that are derived from the GLE and defined solely in terms of the time series of the observed variable. The formulation results in equations of motion without a memory term and hence offers a more intuitive description than the GLE. The framework provided by the present study is expected to elucidate a multi-dimensional dynamics hidden behind the time series of the observed quantity.
Absorption spectrum of KPb2Cl5 thin films
Authors: Yunakova O. N. , Miloslavksy V. K. , Kovalenko E. N. , Kovalenko V. V.
Published: September 2015

A study of the absorption spectrum of thin KPb2Cl5 films, in the spectral range of 2–6 eV, within the temperature interval 90–520 K. It is found that low-frequency exciton states are localized in the sublattice of the compound containing the Pb2+ ions, and that they are excitons of intermediate coupling having a two-dimensional nature.
Analysis of high field effects on the steady-state current-voltage response of semi-insulating 4H-SiC for photoconductive switch applications
Authors: Tiskumara R. , Joshi R. P. , Mauch D. , Dickens J. C. , Neuber A. A.
Published: September 2015

A model-based analysis of the steady-state, current-voltage response of semi-insulating 4H-SiC is carried out to probe the internal mechanisms, focusing on electric field driven effects. Relevant physical processes, such as multiple defects, repulsive potential barriers to electron trapping, band-to-trap impact ionization, and field-dependent detrapping, are comprehensively included. Results of our model match the available experimental data fairly well over orders of magnitude variation in the current density. A number of important parameters are also extracted in the process through comparisons with available data. Finally, based on our analysis, the possible presence of holes in the samples can be discounted up to applied fields as high as ∼275 kV/cm.
Superconducting thin films of (100) and (111) oriented indium doped topological crystalline insulator SnTe
Authors: Si Weidong , Zhang Cheng , Wu Lijun , Ozaki Toshinori , Gu Genda , Li Qiang
Published: September 2015

Recent discovery of the topological crystalline insulator SnTe has triggered a search for topological superconductors, which have potential application to topological quantum computing. The present work reports on the superconducting properties of indium doped SnTe thin films. The (100) and (111) oriented thin films were epitaxially grown by pulsed-laser deposition on (100) and (111) BaF2 crystalline substrates, respectively. The onset superconducting transition temperatures are about 3.8 K for (100) and 3.6 K for (111) orientations, slightly lower than that of the bulk. Magneto-resistive measurements indicate that these thin films may have upper critical fields higher than that of the bulk. With large surface-to-bulk ratio, superconducting indium doped SnTe thin films provide a rich platform for the study of topological superconductivity and potential device applications based on topological superconductors.
Substrate lattice relaxations, spectral distortions, and nanoparticle inclusions of ion implanted zinc oxide
Authors: Wang Y. , Ma B. , Zhang W. , Li D. , Zhao Y. , Finch A. A. , Townsend P. D.
Published: September 2015

Low temperature radioluminescence and thermoluminescence spectra of ZnO track numerous changes produced by copper ion implantation into the surface layer. A significant, but unexpected, feature is that the bulk crystal becomes modified by the stress generated in the surface layer. This is reflected by the energy of intrinsic band gap emission. There are also differences in the spectra and peak temperatures of the thermoluminescence components, consistent with such a structural relaxation. The copper implant layer is both absorbing and reflective, so this introduces major distortions on the radioluminescence component from the bulk region, since the bulk luminescence signals are transmitted through, or reflected from, the implant layer. The temperature dependence of the spectra includes anomalies that are typical of changes driven by phase transitions of nanoparticle inclusions. Overall, the features of bulk relaxation, spectral distortion, and detection of nanoparticle inclusions are rarely considered for ion implanted luminescence studies, but the data suggest they are almost inevitable in a wide range of implanted materials.
On a particular analytical solution to the 3D Navier-Stokes equations and its peculiarity for high Reynolds numbers
Authors: Rabinowitch Alexander S.
Published: September 2015

A special class of axially symmetric nonstationary flows of incompressible viscous fluids is examined. For it, the 3D Navier-Stokes equations are reduced to a nonlinear partial differential equation of the third order and a linear partial differential equation of the second order. These equations are studied and their particular analytical solutions are found. The obtained particular solution to the Navier-Stokes equations could be used to describe some types of turbulent flows of viscous fluids in the case of high Reynolds numbers.
A novel voice coil motor-driven compliant micropositioning stage based on flexure mechanism
Authors: Shang Jiangkun , Tian Yanling , Li Zheng , Wang Fujun , Cai Kunhai
Published: September 2015

This paper presents a 2-degrees of freedom flexure-based micropositioning stage with a flexible decoupling mechanism. The stage is composed of an upper planar stage and four vertical support links to improve the out-of-plane stiffness. The moving platform is driven by two voice coil motors, and thus it has the capability of large working stroke. The upper stage is connected with the base through six double parallel four-bar linkages mechanisms, which are orthogonally arranged to implement the motion decoupling in the x and y directions. The vertical support links with serially connected hook joints are utilized to guarantee good planar motion with heavy-loads. The static stiffness and the dynamic resonant frequencies are obtained based on the theoretical analyses. Finite element analysis is used to investigate the characteristics of the developed stage. Experiments are carried out to validate the established models and the performance of the developed stage. It is noted that the developed stage has the capability of translational motion stroke of 1.8 mm and 1.78 mm in working axes. The maximum coupling errors in the x and y directions are 0.65% and 0.82%, respectively, and the motion resolution is less than 200 nm. The experimental results show that the developed stage has good capability for trajectory tracking.
Commissioning of a frequency-resolved optical gating system at the OMEGA EP laser facility: SpecFROG
Authors: Kemp G. E. , Link A. , Ping Y. , Ayers S. , Patel P. K.
Published: September 2015

We present the design and commissioning of a new single-shot, frequency-resolved optical gating system on the OMEGA EP laser facility — dubbed “SpecFROG” — for characterizing the instantaneous intensity and phase of ∼10 ps pulses used to study ultra-intense laser-plasma interactions. A polarization-gating geometry is employed to ensure tha the diagnostic is broadband and has unambiguous time directionality. SpecFROG is capable of characterizing ∼10 s of mJ pulses with durations between 0.5–25 ps with ≲285 fs geometrical temporal blurring and ∼0.1% spectral shift resolutions over an adjustable total spectral shifting window of ∼15% of the carrier wavelength λo; configurations currently exist for both the fundamental (1ω, λo = 1.054 μm) and second harmonic (2ω, λo = 0.527 μm) of the EP pulse. Initial specular reflectivity measurements of the ∼1 kJ, ∼10 ps OMEGA EP laser off solid density aluminum targets suggest drastically different scalings for specular pulse properties compared to picosecond-scale pulses of comparable intensities.
Metallic-like to nonmetallic transitions in a variety of heavily oxygen deficient ferroelectrics
Authors: Bock Jonathan A. , Lee Soonil , Trolier-McKinstry Susan , Randall Clive A.
Published: September 2015

The coupling between ferroelectric distortions and electron transport is an important factor in understanding ferroelectric/noncentrosymmetric materials with metallic conductivities and ferroelectric-based thermoelectrics. Here, multiple d0 ferroelectrics with a variety of crystal structures are doped via oxygen deficiency, resulting in metallic-like conduction in the paraelectric state. It is found that most of the studied systems show a metallic-like to nonmetallic transition near the paraelectric-ferroelectric transition. The metallic-like to nonmetallic transition temperature can be shifted using mechanisms that shift the paraelectric-ferroelectric transition temperature. It was found that the metallic-like to nonmetallic transition temperature could be shifted from 373 K to 273 K by varying (Ba1−xSrx)TiO3−δ from x = 0 to x = 0.3 and x = 1. The most probable mechanism for ferroelectric-electron transport coupling was determined to be Anderson localization associated with polarization with short-range order.
Degradation of silver near-field optical probes and its electrochemical reversal
Authors: Opilik Lothar , Dogan Üzeyir , Szczerbiński Jacek , Zenobi Renato
Published: September 2015

Deterioration of the outstanding optical properties of elemental silver due to atmospheric corrosion compromises its use in the field of plasmonics. Therefore, more chemically inert, but more lossy, metals (e.g., gold) are often used as a compromise. Silver tips for near-field optical microscopy are only utilized by specialized laboratories with in-house tip production facilities. This article presents a time-dependent study of the effect of atmospheric corrosion on the electromagnetic enhancement of solid silver tips. It was found that chemical degradation renders them unusable for tip-enhanced Raman spectroscopy (TERS) within the first two days after production. Furthermore, we present a simple electrochemical method for recovering the enhancing effect of corroded silver tips, as well as for storing freshly prepared probes, for example, for easy shipment. The present work greatly simplifies the experimental aspects of near-field optical microscopy, which should make near-field optical techniques, and, in particular, TERS, more accessible to the scientific community.
Entropy change of a Ni45.5Co4.5Mn37In13 single crystal studied by scanning calorimetry in high magnetic fields: Field dependence of the magnetocaloric effect
Authors: Bourgault D. , Porcar L. , Rivoirard S. , Courtois P. , Hardy V.
Published: September 2015

By using differential scanning calorimetry, direct entropy variations have been recorded along the martensitic transformation of a Ni45.5Co4.5Mn37In13 single crystal in various magnetic fields. A large negative magnetocaloric effect associated to the transformation from virtually non-magnetic martensite to ferromagnetic austenite coexists with a weaker, positive effect related to the Curie transition in the latter phase. It is shown that the field-dependence of the maximum isothermal entropy change can be modelized by taking into account the interplay of both magnetocaloric contributions, as well as the intrinsic width of the martensitic transformation.
Mapping of axial strain in InAs/InSb heterostructured nanowires
Authors: Patra Atanu , Panda Jaya Kumar , Roy Anushree , Gemmi Mauro , David Jérémy , Ercolani Daniele , Sorba Lucia
Published: September 2015

The article presents a mapping of the residual strain along the axis of InAs/InSb heterostructured nanowires. Using confocal Raman measurements, we observe a gradual shift in the transverse optical phonon mode along the axis of these nanowires. We attribute the observed shift to a residual strain arising from the InAs/InSb lattice mismatch. We find that the strain is maximum at the interface and then monotonically relaxes towards the tip of the nanowires. We also analyze the crystal structure of the InSb segment through selected area electron diffraction measurements and electron diffraction tomography on individual nanowires.
Properties of a weakly ionized NO gas sensor based on multi-walled carbon nanotubes
Authors: Zhang Jingyuan , Zhang Yong , Pan Zhigang , Yang Shuang , Shi Jinghui , Li Shengtao , Min Daomin , Li Xin , Wang Xiaohua , Liu Dingxin , Yang Aijun
Published: September 2015

Nitric oxide NO is one of the major targets for environmental monitoring, but the existing NO sensors are limited by their low sensitivity and narrow test range. Here, a NO gas sensor employing multiwalled carbon nanotubes (MWCNTs) was fabricated, and its properties in NO–N2 mixture were investigated from both emission and ionization. The current Ie passing through the nanotubes cathode was found to decrease with increasing NO concentration and increase linearly in different slopes with the extracting voltage Ue. It is shown that the Schottky barrier of the MWCNTs calculated by Ie increased with NO concentration due to the adsorption of NO gas, which restrained the electron emission and consequently weakened the ionization. The positive ion currents Ic passing through the collecting electrode at different voltages of Ue were found to monotonically decrease with increasing NO concentration, which was induced by both of the reduced electron emission and the consumption of the two excited metastable states N2(A3∑u+) and N2(a′1∑u−) by NO. The sensor exhibited high sensitivity at the low temperature of 30 °C. The calculated conductivity was found to be able to take place of Ic for NO detection in a wide voltage range of 80–150 V Ue.
Coherent phonon spectroscopy of non-fully symmetric modes using resonant terahertz excitation
Authors: Huber T. , Ranke M. , Ferrer A. , Huber L. , Johnson S. L.
Published: September 2015

We use intense terahertz (THz) frequency electromagnetic pulses generated via optical rectification in an organic crystal to drive vibrational lattice modes in single crystal Tellurium. The coherent modes are detected by measuring the polarization changes of femtosecond laser pulses reflecting from the sample surface, resulting in a phase-resolved detection of the coherent lattice motion. We compare the data to a model of Lorentz oscillators driven by the near-single-cycle broadband THz pulse. The demonstrated technique of optically probed coherent phonon spectroscopy with THz frequency excitation could prove to be a viable alternative to other time-resolved spectroscopic methods like standard THz time domain spectroscopy.
Single-mode Fabry-Perot laser with deeply etched slanted double trenches
Authors: Li Xun , Zhu Zhongshu , Xi Yanping , Han Lin , Ke Cheng , Pan Yue , Huang Weiping
Published: September 2015

This work proposed and demonstrated a single-mode Fabry-Perot (FP) laser structure with a pair of deeply etched slanted trenches inside the cavity. We implemented the proposed mode selection scheme in conventional 1310 nm InAlGaAs/InP strained-layer multiple-quantum-well ridge waveguide FP laser diodes and obtained single-mode operation with a side-mode suppression ratio (SMSR) as high as 35 dB. The single-mode yield was approximately 55%, and other device performance measures such as the threshold and the slope efficiency were not greatly affected. Additionally, temperature cycling and aging tests show no exceptional disadvantages when compared with the performance of conventional FP lasers. Fiber-optic transmission tests show that the proposed device can send directly modulated 2.5 Gbps and 6.25 Gbps optical signals for distances of over 50 km in standard single-mode fiber. Thus, as a cost-effective solution, this device is promising as a replacement for conventional distributed feedback laser diodes in specific applications where single-mode operation is indispensable but precise control of the lasing wavelength and/or very high SMSR (e.g., >40 dB) are not required.
Liquid deuterium pressured into becoming metallic
Authors: Chang Sung
Published: September 2015

The world’s strongest pulsed-power source takes a shot at an 80-year-old condensed-matter-physics problem.
A case of melanoma in a native Australian murid, the spinifex hopping-mouse (Notomys alexis)
Authors: Old J. M. , Price M. D.
Published: August 2015

Generally the reporting of diseases and parasites in Australian native murids is rare despite murids making up ~25% of the native mammal fauna of Australia. This paper reports a malignant melanoma in a captive spinifex hopping-mouse (Notomys alexis) and is the first case of melanoma reported in any native Australian murid. With no exposure to ultraviolet radiation the melanoma is proposed to be the result of genetic predisposition and age. As no other reports have been observed in the colony it is likely to be a very rare event in captivity and unlikely to occur in the wild.
Controlled Delivery of Levothyroxine Using Porous Silicon as a Drug Nanocontainer
Authors: Kashanian Soheila , Rostami Elham , Harding Frances J. , McInnes Steven J. P. , Al-Bataineh Sameer , Voelcker Nicolas H.
Published: August 2015

Porous silicon (pSi) materials are regarded as promising drug delivery vehicles due to their biocompatibility, in vivo degradation, and resorption. We examine pSi films as a platform for the controlled delivery of levothyroxine, as a means to overcome problems with consistent dosage of this drug by oral administration. Oxidized pSi films were modified with 3-(aminopropyl)triethoxysilane (APTES), creating a surface chemistry that increased levothyroxine drug loading capacity by 50 % and sustained drug release under physiological conditions for 14 days. Release kinetics from APTES-functionalized films initially followed a zero-order release profile, which is highly desirable for drug delivery. The loading and release profiles of levothyroxine suggest that the film size required to deliver a therapeutic dose is feasible for further consideration as an implantable delivery system.
High-resolution, multiproxy palaeoenvironmental changes recorded from Two Mile Lake, southern Western Australia: implications for Ramsar-listed playa sites
Authors: Gouramanis C. , De Deckker P. , Wilkins D. , Dodson J.
Published: August 2015

Numerous saline playa lakes exist across the arid, semiarid and temperate regions of Australia. These playa lakes exhibit a diverse range of hydrological conditions to which the Australian aquatic invertebrate biota have become adapted and which the biota can utilise as refugia in times of hydrological deterioration. Saline playas also yield palaeoenvironmental records that can be used to infer lacustrine and catchment responses to environmental variability.
We present a palaeoenvironmental record recovered from Two Mile Lake, a saline playa from southern Western Australia. Dating, based on quartz optical luminescence and 14C accelerator mass spectrometry of biogenic carbonates and organic fibres, suggests that most of the sediment was rapidly deposited at 4.36 ± 0.25 thousand years ago. Ostracods and non-marine foraminifera preserved in the sediment show periods of faunal colonisation of the lake with oscillations between hypersaline and oligosaline conditions. The geochemistry of ostracod valves and foraminifera tests suggests higher-frequency variability within the lake, and palynological changes indicate landscape changes, possibly in response to fire. The Two Mile Lake record highlights the utility of saline playas as archives of environmental change that can be used to guide wetland health management, particularly under the impacts of a changing climate.
Primacy of bottom-up effects on a butterflyfish assemblage
Authors: Leahy Susannah M. , Russ Garry R. , Abesamis Rene A.
Published: September 2015

The question of whether biological systems are maintained by top-down versus bottom-up drivers is a recurring one in ecology. It is a particularly important question to address in the management of coral reefs, which are at risk from a variety of anthropogenic stressors. Here, we explicitly test whether the abundance of different feeding guilds of coral-associated Chaetodon butterflyfishes are controlled by top-down or bottom-up drivers, and we assess the relative influence of all statistically significant drivers. We find that the abundance and species richness of Chaetodon butterflyfishes are predominately determined by bottom-up drivers. The abundance of corallivores is primarily driven by availability of branching and tabular live corals, whereas the abundance of generalists is most strongly influenced by a negative association with macroalgal cover. We also find evidence of weak top-down control on the abundance of corallivorous butterflyfish by gape-limited mesopredators, but no such effects on generalist butterflyfish. Our findings indicate that conservation of coral reefs for Chaetodon butterflyfishes must include management at a larger spatial scale in order to reduce the effect of coral reef stressors such as declining water quality and climate change, but should also include implementation of fisheries management tools in order to increase local herbivory.