bluuebunny/crossref_metadata_2025 huggingface dataset:
An injectable acoustic transmitter for juvenile salmon
Authors: Deng Z. D. , Carlson T. J. , Li H. , Xiao J. , Myjak M. J. , Lu J. , Martinez J. J. , Woodley C. M. , Weiland M. A. , Eppard M. B.
Published: January 2015

Salmon recovery and the potential detrimental effects of dams on fish have been attracting national attention due to the environmental and economic implications. In recent years acoustic telemetry has been the primary method for studying salmon passage. However, the size of the existing transmitters limits the minimum size of fish that can be studied, introducing a bias to the study results. We developed the first acoustic fish transmitter that can be implanted by injection instead of surgery. The new injectable transmitter lasts four times longer and weighs 30% less than other transmitters. Because the new transmitter costs significantly less to use and may substantially reduce adverse effects of implantation and tag burden, it will allow for study of migration behavior and survival of species and sizes of fish that have never been studied before. The new technology will lead to critical information needed for salmon recovery and the development of fish-friendly hydroelectric systems.
Correlation of serum KL-6 and CC16 levels with neurodevelopmental outcome in premature infants at 12 months corrected age
Authors: Zhang Zhiqun , Lu Hui , Zhu Yunxia , Xiang Junhua , Huang Xianmei
Published: January 2015

The aim of this study was to evaluate KL-6 and CC16 levels and their correlation with neurodevelopmental outcome among very low birth weight pre-term infants at 12 months corrected age. This prospective cohort study was performed from 2011 to 2013 by enrolling pre-term neonates of gestational age ≤ 32 weeks and birth weight ≤ 1500 g. Serum KL-6 and CC16 levels were determined 7 days after birth and their correlation with neurodevelopment was evaluated using Gesell Mental Developmental Scales. Of the 86 eligible pre-term infants, 63 completed follow-up, of which 15 had bronchopulmonary dysplasia. At 12 months corrected age, 49 infants had favorable outcomes and 14 infants had poor neurodevelopmental outcome. KL-6 levels were higher and CC16 levels were lower in infants with poor neurodevelopmental outcome compared with those infants who had favourable neurodevelopmental outcome. Serum KL-6 levels less than 90.0 ng/ml and CC16 levels greater than 320.0 pg/ml at 7 days of life were found to be predictive of a favourable outcome at 12 months corrected age. These biological markers could predict neurodevelopmental outcome at 12 months corrected age in very low birth weight premature infants and help the clinician plan early therapeutic interventions to minimize or avoid poor neurodevelopmental outcome.
Detrended Partial-Cross-Correlation Analysis: A New Method for Analyzing Correlations in Complex System
Authors: Yuan Naiming , Fu Zuntao , Zhang Huan , Piao Lin , Xoplaki Elena , Luterbacher Juerg
Published: January 2015

In this paper, a new method, detrended partial-cross-correlation analysis (DPCCA), is proposed. Based on detrended cross-correlation analysis (DCCA), this method is improved by including partial-correlation technique, which can be applied to quantify the relations of two non-stationary signals (with influences of other signals removed) on different time scales. We illustrate the advantages of this method by performing two numerical tests. Test I shows the advantages of DPCCA in handling non-stationary signals, while Test II reveals the “intrinsic” relations between two considered time series with potential influences of other unconsidered signals removed. To further show the utility of DPCCA in natural complex systems, we provide new evidence on the winter-time Pacific Decadal Oscillation (PDO) and the winter-time Nino3 Sea Surface Temperature Anomaly (Nino3-SSTA) affecting the Summer Rainfall over the middle-lower reaches of the Yangtze River (SRYR). By applying DPCCA, better significant correlations between SRYR and Nino3-SSTA on time scales of 6 ~ 8 years are found over the period 1951 ~ 2012, while significant correlations between SRYR and PDO on time scales of 35 years arise. With these physically explainable results, we have confidence that DPCCA is an useful method in addressing complex systems.
Simple fluorinated moiety insertion on Aβ 16–23 peptide for stain-free TEM imaging
Authors: Sonzini Silvia , Jones Samuel T. , Walsh Zarah , Scherman Oren A.
Published: January 2015

We report a synthetically straightforward procedure that allows for stain-free TEM of amyloidogenic peptide fibres through a simple addition of a fluorinated moiety via SPPS.
Evaluation of Analytical Instrumentation. Part XXVI: Instrumentation for Voltammetry
Authors: Braungardt C. B.
Published: January 2015

The Analytical Methods Committee has received and approved the following report from the Instrumental Criteria Sub-Committee.
Dipicolinic acid: a strong anchoring group with tunable redox and spectral behavior for stable dye-sensitized solar cells
Authors: Gabrielsson Erik , Tian Haining , Eriksson Susanna K. , Gao Jiajia , Chen Hong , Li Fusheng , Oscarsson Johan , Sun Junliang , Rensmo Håkan , Kloo Lars , Hagfeldt Anders , Sun Licheng
Published: January 2015

Dipicolinic acid was investigated as a new anchoring group for DSSCs with unpredictable response to different electrolytes in dye-sensitized solar cells.
The development of a highly photostable and chemically stable zwitterionic near-infrared dye for imaging applications
Authors: Su Dongdong , Teoh Chai Lean , Samanta Animesh , Kang Nam-Young , Park Sung-Jin , Chang Young-Tae
Published: January 2015

ZWCC, a new zwitterionic NIR dye with high photostability and enhanced chemical stability, can be easily functionalized for biological applications.
Nuclease resistant oligonucleotides with cell penetrating properties
Authors: Milton Stefan , Honcharenko Dmytro , Rocha Cristina S. J. , D. Moreno Pedro M. , Edvard Smith C. I. , Strömberg Roger
Published: January 2015

2′-O-AECM modified oligonucleotides provide a combination of remarkable properties, such as high stability towards degradation, stable duplexes with RNA and enhanced cellular uptake.
Influence of the chirality of short peptide supramolecular hydrogels in protein crystallogenesis
Authors: Conejero-Muriel Mayte , Gavira José A. , Pineda-Molina Estela , Belsom Adam , Bradley Mark , Moral Mónica , Durán Juan de Dios García-López , Luque González Angélica , Díaz-Mochón Juan J. , Contreras-Montoya Rafael , Martínez-Peragón Ángela , Cuerva Juan M. , Álvarez de Cienfuegos Luis
Published: January 2015

Influence of gel chirality in protein crystallogenesis.
An efficient approach to prepare boronate core–shell polymer nanoparticles for glycoprotein recognition via combined distillation precipitation polymerization and RAFT media precipitation polymerization
Authors: Liu Jianxi , Yang Kaiguang , Qu Yanyan , Li Senwu , Wu Qi , Liang Zhen , Zhang Lihua , Zhang Yukui
Published: January 2015

Boronic functional core–shell polymer particles were synthesized by a unique strategy for the stimuli-response to cis-diol-containing molecules.
[V@Ge8As4]3−and [Nb@Ge8As6]3−: encapsulation of electron-poor transition metal atoms
Authors: Mitzinger Stefan , Broeckaert Lies , Massa Werner , Weigend Florian , Dehnen Stefanie
Published: January 2015

The first known M–As–Ge clusters, [V@Ge8As4]3−and [Nb@Ge8As6]3−, exhibit non-deltahedral topologies, with “V5+” being the hardest cation ever embedded in endohedral Zintl anions.
Room temperature Suzuki coupling of aryl iodides, bromides, and chlorides using a heterogeneous carbon nanotube-palladium nanohybrid catalyst
Authors: Jawale Dhanaji V. , Gravel Edmond , Boudet Caroline , Shah Nimesh , Geertsen Valérie , Li Haiyan , Namboothiri Irishi N. N. , Doris Eric
Published: January 2015

Palladium nanoparticles were immobilized on multi-walled carbon nanotubes by a layer-by-layer approach, resulting in a well-defined assembly that was used as a heterogenous catalyst in Suzuki couplings.
Artificial synthetic MnIVCa–oxido complexes mimic the oxygen-evolving complex in photosystem II
Authors: Chen Changhui , Zhang Chunxi , Dong Hongxing , Zhao Jingquan
Published: January 2015

Artificial synthetic MnIVCa–oxido complexes containing reactive water molecules have been synthesized to mimic the oxygen-evolving center in photosystem II.
Assembly of various degrees of interpenetration of Co-MOFs based on mononuclear or dinuclear cluster units: magnetic properties and gas adsorption
Authors: Zheng Meng-Xi , Gao Xiang-Jing , Zhang Chuan-Lei , Qin Ling , Zheng He-Gen
Published: January 2015

Mononuclear or dinuclear Co cluster units are interconnected by mixed ligands, resulting in interesting structural diversity and various degrees of interpenetration.
Synthesis and evaluation of a series of resveratrol analogues as potent anti-cancer agents that target tubulin
Authors: Madadi Nikhil R. , Zong Hongliang , Ketkar Amit , Zheng Chen , Penthala Narsimha R. , Janganati Venumadhav , Bommagani Shobanbabu , Eoff Robert L. , Guzman Monica L. , Crooks Peter A.
Published: January 2015

Novel resveratrol analogues have been synthesized and evaluated for their anticancer activities against a panel of 60 human cancer cell lines.
Metastability of the atomic structures of size-selected gold nanoparticles
Authors: Wells Dawn M. , Rossi Giulia , Ferrando Riccardo , Palmer Richard E.
Published: January 2015

All nanostructures are metastable – but some are more metastable than others. Size-selected gold nanoclusters present icosahedral, decahedral or fcc structures. Fcc are the most stable; the others are locked in by template growth.
An Nd3+-sensitized upconversion nanophosphor modified with a cyanine dye for the ratiometric upconversion luminescence bioimaging of hypochlorite
Authors: Zou Xianmei , Liu Yi , Zhu Xingjun , Chen Min , Yao Liming , Feng Wei , Li Fuyou
Published: January 2015

An Nd3+-sensitized upconversion nanosystem was successfully used as a high-contrast nanoprobe for probing ClO− in living cells and as an in vivo mouse model of arthritis under 808 nm irradiation.
Recent developments of the in situ wet cell technology for transmission electron microscopies
Authors: Chen Xin , Li Chang , Cao Hongling
Published: January 2015

In situ wet cells for transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) allow studying structures and processes in a liquid environment with high temporal and spatial resolutions, and have been attracting increasing research interests in many fields.
Structure dependent active sites of NixSy as electrocatalysts for hydrogen evolution reaction
Authors: Chung Dong Young , Han Joung Woo , Lim Dong-Hee , Jo Jun-Ho , Yoo Sung Jong , Lee Hyunjoo , Sung Yung-Eun
Published: January 2015

Structure effects of NiS and Ni3S2 nanoparticles were investigated for their electrocatalytic activity in the hydrogen evolution reaction in both acid and alkaline media.
Synthesis of comb-like poly(ethyleneimine)s and their application in biomimetic silicification
Authors: Yao Dong-Dong , Jin Ren-Hua
Published: January 2015

In this paper, we firstly synthesized comb polymers with crystallizable poly(ethyleneimine) (PEI) side chains, and further investigated their self-assembly behavior and catalytic templating role for silicification.
A simple approach to hybrid inorganic–organic step-growth hydrogels with scalable control of physicochemical properties and biodegradability
Authors: Alves F. , Nischang I.
Published: January 2015

We prepared new and scalable, hybrid inorganic–organic step-growth hydrogels with polyhedral oligomeric silsesquioxane (POSS) network knot construction elements and hydrolytically degradable poly(ethylene glycol) (PEG) di-ester macromonomers by in situ radical-mediated thiol–ene photopolymerization.
Enhancement of stereoselectivities in asymmetric synthesis using fluorinated solvents, auxiliaries, and catalysts
Authors: Sugiishi Tsuyuka , Matsugi Masato , Hamamoto Hiromi , Amii Hideki
Published: January 2015

In this review, the drastic changes using fluorinated solvents, additives, auxiliaries, and catalysts in catalytic asymmetric transformations are presented.
Comprehensive chemical secretory measurement of single cells trapped in a micro-droplet array with mass spectrometry
Authors: Fujita Hideaki , Esaki Tsuyoshi , Masujima Tsutomu , Hotta Akitsu , Kim Soo Hyeon , Noji Hiroyuki , Watanabe Tomonobu M.
Published: January 2015

By trapping individual single cells in a micro-well, molecules secreted by a single cell can be analyzed using mass spectrometry.
Superior nano-mechanical properties of reduced graphene oxide reinforced polyurethane composites
Authors: Gupta Tejendra K. , Singh Bhanu P. , Tripathi Ravi Kant , Dhakate Sanjay R. , Singh Vidya N. , Panwar O. S. , Mathur Rakesh B.
Published: January 2015

RGO reinforced polymer composites with significantly enhanced nanomechanical properties useful for automobile, wind mill blade industries and also in hard and scratch-less coatings on automotive vehicles have been synthesized.
Biological and pharmacological activities of amaryllidaceae alkaloids
Authors: He Maomao , Qu Chunrong , Gao Oude , Hu Xianming , Hong Xuechuan
Published: January 2015

This review discusses the recent developments on biological and pharmacological activities of amaryllidaceae alkaloids with IC50or EC50values since 2005, supporting the potential therapeutic possibilities for the use of these compounds.
Electrochemical performance of an asymmetric supercapacitor based on graphene and cobalt molybdate electrodes
Authors: Veerasubramani Ganesh Kumar , Krishnamoorthy Karthikeyan , Kim Sang Jae
Published: January 2015

In this article, we report the fabrication and electrochemical performance of asymmetric supercapacitors (ASCs) based on a reduced graphene oxide (rGO) negative electrode and a cobalt molybdate (CoMoO4) positive electrode.
A free radical assisted strategy for preparing functionalized carbon nanotubes as a highly efficient nucleating agent for poly(l-lactide)
Authors: Zhang Zi-Jing , Cui Wei , Xu Huan , Xie Lan , Liu Huan , Zhu Le-Min , Li Hang , Ran Rong
Published: January 2015

Schematic illumination of the fabrication of the CNT-OEG via free radical polymerization.
Tough and VEGF-releasing scaffolds composed of artificial silk fibroin mats and a natural acellular matrix
Authors: Li Zhaobo , Song Lujie , Huang Xiangyu , Wang Hongsheng , Shao Huili , Xie Minkai , Xu Yuemin , Zhang Yaopeng
Published: January 2015

The blend and coaxially electrospun RSF/BAMG composite scaffolds loaded VEGF exhibited good cell compatibility with improved mechanical properties.
Vibrational and electronic peculiarities of NiTiO3nanostructures inferred from first principle calculations
Authors: Ruiz Preciado M. A. , Kassiba A. , Morales-Acevedo A. , Makowska-Janusik M.
Published: January 2015

Structural, electronic and vibrational properties of nanostructured (NiTiO3)nclusters were calculated by numerical models based on DFT and semi-empirical quantum chemistry codes.
A meta-molecular tailoring strategy towards an efficient violet-blue organic electroluminescent material
Authors: Chen Wen-Cheng , Wu Guang-Fu , Yuan Yi , Wei Huai-Xin , Wong Fu-Lung , Tong Qing-Xiao , Lee Chun-Sing
Published: January 2015

In this study, a novel violet-blue emitter m-BBTPI was designed and synthesized via meta-molecular tailoring. Using m-BBTPI as non-doped emitter, we obtained a high-efficiency violet-blue organic electroluminescent device.
Fabrication of resin supported Au–Pd bimetallic nanoparticle composite to efficiently remove chloramphenicol from water
Authors: Wang Xu , Wang Yun-Xia , Yuan Baoling , Cui Hao-Jie , Fu Ming-Lai
Published: January 2015

Au–Pd bimetallic nanoparticles were loaded on the amberlite 717 to form a catalytic system (717@Au–Pd), which exhibited excellent activity for removing environmental pollutants such as chloramphenicol containing carbon–halogen bonds.
Ruthenium-caged antisense morpholinos for regulating gene expression in zebrafish embryos
Authors: Griepenburg Julianne C. , Rapp Teresa L. , Carroll Patrick J. , Eberwine James , Dmochowski Ivan J.
Published: January 2015

Ruthenium photolinkers provide a versatile method of using visible light to control structure and function of biopolymers.
Synthesis and self-assembly of phthalocyanine-tethered block copolymers
Authors: Aimi Junko , Komura Motonori , Iyoda Tomokazu , Saeki Akinori , Seki Shu , Takeuchi Masayuki , Nakanishi Takashi
Published: January 2015

Novel block copolymers bearing a phthalocyanine were synthesized via atom transfer radical polymerization and “click” chemistry. Self-assembled nanoarchitectures are obtained through microphase separation of the block copolymers and phthalocyanine π–π interactions.
Behavioral and dopaminergic damage induced by acute iron toxicity in Caenorhabditis elegans
Authors: Fagundez Daiandra de Almeida , Câmara Daniela Freitas , Salgueiro Willian Goulart , Noremberg Simone , Luiz Puntel Robson , Piccoli Jacqueline Escobar , Garcia Solange Cristina , da Rocha João Batista Teixeira , Aschner Michael , Ávila Daiana Silva
Published: January 2015

Iron (Fe) exposure, results in multiple biological defects inC. elegans, including reproductive and motor impairment, which may be related to oxidative stress and neuronal damage.
Genosensor based on a nanostructured, platinum-modified glassy carbon electrode for Listeria detection
Authors: Kashish Kashish , Gupta Sandeep , Dubey Suresh Kumar , Prakash Rajiv
Published: January 2015

In this article, we describe the development of a simple and cost-effective genosensor probe based on a glassy carbon electrode modified with platinum nanomaterials dispersed in a chitosan matrix.
Electrode modified with porous alumina microfibers as a highly sensitive electrochemical sensor for quercetin
Authors: Li Yaohua , Huang Wensheng
Published: January 2015

Porous alumina microfibers were prepared, and used to construct a highly sensitive electrochemical sensor for quercetin.
Scaling up an electrochemical signal with a catalytic hairpin assembly coupling nanocatalyst label for DNA detection
Authors: Hun Xu , Xie Guoliang , Luo Xiliang
Published: January 2015

A new strategy for the electrochemical detection of DNA based on catalytic hairpin assembly combined with nanocatalyst label-based redox cycling reaction signal amplification. A superior detection limit of 0.3 aM toward DNA was achieved.
Molecular wires
Authors: Guldi Dirk M. , Nishihara Hiroshi , Venkataraman Latha
Published: January 2015

Guest editors Dirk M. Guldi, Hiroshi Nishihara and Latha Venkataraman introduce the Molecular Wires issue of Chemical Society Reviews.
Nanocrystalline magnesium oxide-stabilized palladium(0): an efficient and reusable catalyst for synthesis of N-(2-pyridyl)indoles
Authors: Reddy Police Vishnuvardhan , Annapurna Manne , Srinivas Pottabathula , Likhar Pravin R. , Lakshmi Kantam Mannepalli
Published: January 2015

The synthesis of N-(2-pyridyl)indoles by NAP–Mg–Pd(0) catalyzed oxidative coupling between N-aryl-2-aminopyridines and alkynes.
Photocatalytic secondary amine synthesis from azobenzenes and alcohols on TiO2 loaded with Pd nanoparticles
Authors: Selvam Kaliyamoorthy , Sakamoto Hirokatsu , Shiraishi Yasuhiro , Hirai Takayuki
Published: January 2015

Photoexcitation of TiO2 loaded with Pd particles produces secondary amines from azobenzenes and alcohols with almost quantitative yields, via consecutive photocatalytic and catalytic actions.
Complexation of triblock reverse copolymer 10R5 with surface active ionic liquids in aqueous medium: a physico-chemical study
Authors: Sharma Renu , Kang Tejwant Singh , Mahajan Rakesh Kumar
Published: January 2015

A comprehensive study on the interactions of surface active ionic liquids (SAILs) [Cnmim][Cl], where n = 8, 10, and 12, with a triblock reverse copolymer, 10R5, [(PPO)8–(PEO)22–(PPO)8] has been performed using various physico-chemical techniques.
Synergetic effect between photocatalysis on TiO2 and solar light-driven thermocatalysis on MnOx for benzene purification on MnOx/TiO2 nanocomposites
Authors: Ma Yan , Li Yuanzhi , Mao Mingyang , Hou Jingtao , Zeng Min , Zhao Xiujian
Published: January 2015

We realize full solar spectrum, visible-infrared catalysis for benzene oxidation by developing novel solar light-driven thermocatalysis on MnOx/TiO2 nanocomposite, and find a synergetic effect between photocatalysis and thermocatalysis.
Angiotensin II, oxidative stress and stem cell therapy: a matter of delicacy
Authors: Roks Anton J.M.
Published: January 2015

Optimization of stem cell therapy after cardiovascular and renal injury depends on many factors, among which is stem cell donor health. The renin–angiotensin system (RAS) plays an important role in cardiovascular and renal homoeostasis and pathophysiology. It is becoming increasingly clear that the RAS affects the therapeutic performance of stem cells. In this issue of Clinical Science, Kankuri et al. dig deeper into the consequences of excessive angiotensin II signalling and reactive oxygen species (ROS) formation in the stem cell donor, applying a model of regenerative medicine after renal injury.
Lexical Effects on Children's Speech Processing: Individual Differences Reflected in the Autism-Spectrum Quotient (AQ)
Authors: Ota Mitsuhiko , Stewart Mary E. , Petrou Alexandra M. , Dickie Catherine
Published: January 2015

Purpose

This study was undertaken to examine whether children exhibit the same relationship that adults show between lexical influence on phoneme identification and individual variation on the Autism-Spectrum Quotient (AQ).

Method

Data from 62 4- to 7-year-olds with no diagnosis of autism were analyzed. The main task involved identification of the initial sound in pairs of voice-onset time continua with a real word on one end and a nonword on the other (e.g.,
gift–kift
,
giss–kiss
). Participants were also given the children's version of the AQ and a 2nd instrument related to autistic-like traits, the Social Responsiveness Scale (SRS).

Results

The lexical shift was related to the AQ (particularly to its Attention Switching subscale) but not to the SRS.

Conclusions

The size of lexical effects on children's speech perception can be predicted by AQ scores but not necessarily by other measures of autism-like traits. The results indicate that speech perception in children manifests individual differences along some general dimension of cognitive style reflected in the AQ, possibly in relation to local/global information processing.
Spectrum handoff based on adaptive weights adjustment
Authors: Zhi‐jin Zhao , Lu‐ping Zhang , Hai‐quan Wang
Published: January 2015

Spectrum handoff is one of key technologies of cognitive radio. A spectrum handoff strategy based on adaptive weights adjustment is proposed, considering the effect of secondary users’ (SUs) transmission power, fading factor, bandwidth and channel availability on the target channel selecting. According to the principle of multi‐attribute simple additive weight algorithm (MA‐SAW), the expected effect function of each channel is obtained by analysis. Making full use of the change of the various factors in cognitive wireless network, the LMS adaptive algorithm of dynamic weights is put forward. Finally, the dynamic weights are applied to MA‐SAW, to determine target channel to switch. The simulation results show that the proposed algorithm can reduce the switching times of SUs, and improve the effective transmission rate.
A first-principles study of the electronic and structural properties of Sb and F doped SnO2 nanocrystals
Authors: Kim Minjung , Marom Noa , Scott Bobbitt N. , Chelikowsky James R.
Published: January 2015

We examine the electronic properties of Sb and F doped SnO2 nanocrystals up to 2.4 nm in diameter. A real-space pseudopotential implementation of density functional theory is employed within the local density approximation. We calculate electron binding energies and dopant formation energies as function of nanocrystal size, dopant concentration, and dopant species. Structural changes for different dopant species are also investigated. Our study should provide useful information for the design of transparent conducting oxides at the nanoscale.
Note: Sample cells to investigate solid/liquid interfaces with neutrons
Authors: Rennie Adrian R. , Hellsing Maja S. , Lindholm Eric , Olsson Anders
Published: January 2015

The design of sample cells to study solid/liquid interfaces by neutron reflection is presented. Use of standardized components and a modular design has allowed a wide range of experiments that include grazing incidence scattering and conventional small-angle scattering. Features that reduce background scattering are emphasized. Various flow arrangements to fill and replenish the liquid in the cell as well as continuous stirring are described.
Operating single quantum emitters with a compact Stirling cryocooler
Authors: Schlehahn A. , Krüger L. , Gschrey M. , Schulze J.-H. , Rodt S. , Strittmatter A. , Heindel T. , Reitzenstein S.
Published: January 2015

The development of an easy-to-operate light source emitting single photons has become a major driving force in the emerging field of quantum information technology. Here, we report on the application of a compact and user-friendly Stirling cryocooler in the field of nanophotonics. The Stirling cryocooler is used to operate a single quantum emitter constituted of a semiconductor quantum dot (QD) at a base temperature below 30 K. Proper vibration decoupling of the cryocooler and its surrounding enables free-space micro-photoluminescence spectroscopy to identify and analyze different charge-carrier states within a single quantum dot. As an exemplary application in quantum optics, we perform a Hanbury-Brown and Twiss experiment demonstrating a strong suppression of multi-photon emission events with g(2)(0) < 0.04 from this Stirling-cooled single quantum emitter under continuous wave excitation. Comparative experiments performed on the same quantum dot in a liquid helium (LHe)-flow cryostat show almost identical values of g(2)(0) for both configurations at a given temperature. The results of this proof of principle experiment demonstrate that low-vibration Stirling cryocoolers that have so far been considered exotic to the field of nanophotonics are an attractive alternative to expensive closed-cycle cryostats or LHe-flow cryostats, which could pave the way for the development of high-quality table-top non-classical light sources.
Experimental evidence of excited electron number density and temperature effects on electron-phonon coupling in gold films
Authors: Giri Ashutosh , Gaskins John T. , Foley Brian M. , Cheaito Ramez , Hopkins Patrick E.
Published: January 2015

The electronic transport properties of metals with weak electron-phonon coupling can be influenced by non-thermal electrons. Relaxation processes involving non-thermal electrons competing with the thermalized electron system have led to inconsistencies in the understanding of how electrons scatter and relax with the less energetic lattice. Recent theoretical and computational works have shown that the rate of energy relaxation with the metallic lattice will change depending on the thermalization state of the electrons. Even though 20 years of experimental works have focused on understanding and isolating these electronic relaxation mechanisms with short pulsed irradiation, discrepancies between these existing works have not clearly answered the fundamental question of the competing effects between non-thermal and thermal electrons losing energy to the lattice. In this work, we demonstrate the ability to measure the electron relaxation for varying degrees of both electron-electron and electron-phonon thermalization. This series of measurements of electronic relaxation over a predicted effective electron temperature range up to ∼3500 K and minimum lattice temperatures of 77 K validate recent computational and theoretical works that theorize how a nonequilibrium distribution of electrons transfers energy to the lattice. Utilizing this wide temperature range during pump-probe measurements of electron-phonon relaxation, we explain discrepancies in the past two decades of literature of electronic relaxation rates. We experimentally demonstrate that the electron-phonon coupling factor in gold increases with increasing lattice temperature and laser fluences. Specifically, we show that at low laser fluences corresponding to small electron perturbations, energy relaxation between electrons and phonons is mainly governed by non-thermal electrons, while at higher laser fluences, non-thermal electron scattering with the lattice is less influential on the energy relaxation mechanisms.
Quantum systems with position-dependent mass and spin-orbit interaction via Rashba and Dresselhaus terms
Authors: Schmidt Alexandre G. M. , Portugal L. , de Jesus Anderson L.
Published: January 2015

We consider a particle with spin 1/2 with position-dependent mass moving in a plane. Considering separately Rashba and Dresselhaus spin-orbit interactions, we write down the Hamiltonian for this problem and solve it for Dirichlet boundary conditions. Our radial wavefunctions have two contributions: homogeneous ones which are written as Bessel functions of non-integer orders—that depend on angular momentum m—and particular solutions which are obtained after decoupling the non-homogeneous system. In this process, we find non-homogeneous Bessel equation, Laguerre, as well as biconfluent Heun equation. We also present the probability densities for m = 0, 1, 2 in an annular quantum well. Our results indicate that the background as well as the spin-orbit interaction naturally splits the spinor components.
Optimal control of the signal-to-noise ratio per unit time of a spin 1/2 particle: The crusher gradient and the radiation damping cases
Authors: Lapert M. , Assémat E. , Glaser S. J. , Sugny D.
Published: January 2015

We show to which extent the signal to noise ratio per unit time of a spin 1/2 particle can be maximized. We consider a cyclic repetition of experiments made of a measurement followed by a radio-frequency magnetic field excitation of the system, in the case of unbounded amplitude. In the periodic regime, the objective of the control problem is to design the initial state of the system and the pulse sequence which leads to the best signal to noise performance. We focus on two specific issues relevant in nuclear magnetic resonance, the crusher gradient and the radiation damping cases. Optimal control techniques are used to solve this non-standard control problem. We discuss the optimality of the Ernst angle solution, which is commonly applied in spectroscopic and medical imaging applications. In the radiation damping situation, we show that in some cases, the optimal solution differs from the Ernst one.
Weakly nonlinear instability of planar viscoelastic sheets
Authors: Wang Chen , Yang Li-jun , Xie Luo , Chen Pi-min
Published: January 2015

A second-order weakly nonlinear analysis has been made of the temporal instability for the linear sinuous mode of two-dimensional planar viscoelastic liquid sheets moving in an inviscid gas. The convected Jeffreys models including the corotational Jeffreys model, Oldroyd A model, and the Oldroyd B model are considered as the rheology model of the viscoelastic fluid of the sheet. The solution for the second-order gas-to-liquid interface displacement has been derived, and the temporal evolution leading to the breakup has been shown. The second-order interface displacement of the linear sinuous mode is varicose, which causes the sheet to fragment into ligaments. First-order constitutive relations of the three rheology models become identical after linearization, so the linear instability results are also the same. For the second-order weakly nonlinear instability, the second-order constitutive relation varies among the corotational Jeffreys model, Oldroyd A model, and the Oldroyd B model, but although they have different disturbance pressures, their disturbance velocities and interface displacements are the same, and therefore, the sheets of the corotational Jeffreys fluid, Oldroyd A fluid, and the Oldroyd B fluid have the same instability behavior characterized by the wave profile and breakup time. The reason for the identical instability behavior is that the effect of different codeformations of the corotational frame, covariant frame, and the contravariant frame is counteracted by the corresponding change in the second-order disturbance pressure, leaving no influence on the second-order velocity. At wavenumbers with maximum instabilities, an increase in the elasticity, or a reduction of the deformation retardation time, leads to a larger linear temporal growth rate, greater second-order disturbance amplitude, and shorter breakup time, thereby enhancing instability. The mechanism of linear instability has been examined using an energy approach, which shows that the main cause of instability is the aerodynamic force.
Reliability evaluation of a standalone wind-photovoltaic/battery energy system based on realistic model of battery
Authors: Delavaripour Hossein , Dehkordi Behzad Mirzaeian
Published: January 2015

This paper presents the reliability evaluation technique of a standalone system including renewable energy resources such as wind and photovoltaic (PV), integrated with battery energy storage system. The focus in this study is on the effect of the operating restrictions of battery on system reliability by presenting a new modeling of battery. In this regard, the proposed reliability evaluation method is based on the combination of the analytical and simulation approaches in the domain of adequacy studies. In this technique based on time series approach, the realistic model of the electrochemical behaviors for the battery bank can be considered. The electrochemical behaviors change in different operation conditions, i.e., temperature, state of charge and charging/discharging current. In this way, a sample lead-acid battery is considered and then a new capacity model for the battery bank is presented based on the realistic electrochemical behaviors related to reserve applications. Simulation results for a case study are presented. The influence of battery modeling in the different studies is discussed and the beneficial results are assessed.
Tuning optical properties of transparent conducting barium stannate by dimensional reduction
Authors: Li Yuwei , Zhang Lijun , Ma Yanming , Singh David J.
Published: January 2015

We report calculations of the electronic structure and optical properties of doped n-type perovskite BaSnO3 and layered perovskites. While doped BaSnO3 retains its transparency for energies below the valence to conduction band onset, the doped layered compounds exhibit below band edge optical conductivity due to transitions from the lowest conduction band. This gives absorption in the visible for Ba2SnO4. Thus, it is important to minimize this phase in transparent conducting oxide (TCO) films. Ba3Sn2O7 and Ba4Sn3O10 have strong transitions only in the red and infrared, respectively. Thus, there may be opportunities for using these as wavelength filtering TCO.
An ultrasensitive, uniform and large-area surface-enhanced Raman scattering substrate based on Ag or Ag/Au nanoparticles decorated Si nanocone arrays
Authors: Zhang P. P. , Gao J. , Sun X. H.
Published: January 2015

Large-area and highly ordered Si nanocone arrays decorated with Ag or Au/Ag nanoparticles have been fabricated via a mask-free lithography with reaction ion etching, followed by metal deposition process. Ultrasensitive surface enhanced Raman scattering signals with an enhancement factor of 1012 were achieved even at the concentration of the Rhodamine 6G as low as 10−15 M. The surface-enhanced Raman spectroscopy (SERS) substrate was also applied on the detection of Sudan I dye and the Raman signals were substantially enhanced as well. The stability of the SERS substrate can be significantly improved by covering Ag nanoparticles with Au thin layer, which maintain a high SERS performance even after one month storage. This nanofabrication process appears to be a feasible approach to prepare uniform and reproducible SERS-active substrates with high sensitivity and stability for practical SERS applications.
Isolated Ti in Si: Deep level transient spectroscopy, minority carrier transient spectroscopy, and high-resolution Laplace deep level transient spectroscopy studies
Authors: Scheffler L. , Kolkovsky Vl. , Weber J.
Published: January 2015

Combining deep level transient spectroscopy (DLTS), high-resolution Laplace DLTS, and minority carrier transient spectroscopy studies, we question the identification of the dominant Ti-related defects introducing deep levels (E40, E150, and H180) in n- and p-type Si. The observed results cannot unambiguously support the models previously reported for these defects. The presence of the Poole-Frenkel effect describing the enhancement of the emission rates of E40 as a function of electric field is not consistent with the previous assignment of this defect to the single acceptor, whereas the absence of the enhancement of the emission rate of E150 under different reverse bias applied to the diode does not confirm the previous attribution of this defect to the single donor in n-type Si. The attribution of H180 to the double donor is in good agreement with our results. In contrast, the identical depth profiles obtained for E40 and E150 in bulk of as-grown, hydrogenated and annealed samples cannot be explained by the assignment of these levels to different defects.
Joule heating-assisted growth of Cu(In,Ga)Se2 solar cells
Authors: Rampino S. , Annoni F. , Bronzoni M. , Calicchio M. , Gombia E. , Mazzer M. , Pattini F. , Gilioli E.
Published: January 2015

We report on the development of an unconventional method for heating a Mo-coated substrate during the deposition of a Cu(In,Ga)Se2 (CIGS) layer by the pulsed electron deposition technique, to be used as absorber in thin film solar cells. This method is based on the application of a DC electrical power directly through the Mo back contact of the cell, converting electrical energy into heat by Joule effect. Since the current flows only on the superficial metal-coated region of the substrate, a localized heating of the surface can be achieved, thus limiting the heat losses. Due to the very efficient heat transfer to the thin Mo layer, a very little electrical power density (few W/cm2) is enough to achieve the required deposition temperature on the Mo surface, much lower compared to the traditional resistor- or lamp-based external heaters. The morphological and electrical properties of Joule-heated samples have been compared to those of CIGS films heated by a conventional external heater. As far as the structure concerns, a remarkable difference is revealed by Scanning Electron Microscopy analysis, indicating a significant enlargement of the CIGS grains size on Joule-heated samples. On the contrary, Capacitance-Voltage and Current-Voltage measurements evidence similar electrical features: both types of heated samples have a net free carrier concentration ≈5 × 1015 cm−3, resulting in a similar photovoltaic conversion efficiency (≈15%). The main recombination path, deduced from the dependence of VOC on the temperature, results to be the Shockley-Read-Hall mechanism in both types of the absorber layer. These results indicate that the Joule effect could be adopted as a feasible, low cost alternative heating method for growing high quality CIGS layers.
Hole traps associated with high-concentration residual carriers in p-type GaAsN grown by chemical beam epitaxy
Authors: Elleuch Omar , Wang Li , Lee Kan-Hua , Demizu Koshiro , Ikeda Kazuma , Kojima Nobuaki , Ohshita Yoshio , Yamaguchi Masafumi
Published: January 2015

The hole traps associated with high background doping in p-type GaAsN grown by chemical beam epitaxy are studied based on the changes of carrier concentration, junction capacitance, and hole traps properties due to the annealing. The carrier concentration was increased dramatically with annealing time, based on capacitance–voltage (C–V) measurement. In addition, the temperature dependence of the junction capacitance (C–T) was increased rapidly two times. Such behavior is explained by the thermal ionization of two acceptor states. These acceptors are the main cause of high background doping in the film, since the estimated carrier concentration from C–T results explains the measured carrier concentration at room temperature using C–V method. The acceptor states became shallower after annealing, and hence their structures are thermally unstable. Deep level transient spectroscopy (DLTS) showed that the HC2 hole trap was composed of two signals, labeled HC21 and HC22. These defects correspond to the acceptor levels, as their energy levels obtained from DLTS are similar to those deduced from C–T. The capture cross sections of HC21 and HC22 are larger than those of single acceptors. In addition, their energy levels and capture cross sections change in the same way due to the annealing. This tendency suggests that HC21 and HC22 signals originate from the same defect which acts as a double acceptor.
Tunable enhanced optical absorption of graphene using plasmonic perfect absorbers
Authors: Cai Yijun , Zhu Jinfeng , Liu Qing Huo
Published: January 2015

Enhancement and manipulation of light absorption in graphene is a significant issue for applications of graphene-based optoelectronic devices. In order to achieve this purpose in the visible region, we demonstrate a design of a graphene optical absorber inspired by metal-dielectric-metal metamaterial for perfect absorption of electromagnetic waves. The optical absorbance ratios of single and three atomic layer graphene are enhanced up to 37.5% and 64.8%, respectively. The graphene absorber shows polarization-dependence and tolerates a wide range of incident angles. Furthermore, the peak position and bandwidth of graphene absorption spectra are tunable in a wide wavelength range through a specific structural configuration. These results imply that graphene in combination with plasmonic perfect absorbers have a promising potential for developing advanced nanophotonic devices.
Nanometer-scale surface potential and resistance mapping of wide-bandgap Cu(In,Ga)Se2 thin films
Authors: Jiang C.-S. , Contreras M. A. , Mansfield L. M. , Moutinho H. R. , Egaas B. , Ramanathan K. , Al-Jassim M. M.
Published: January 2015

We report microscopic characterization studies of wide-bandgap Cu(In,Ga)Se2 photovoltaic thin films using the nano-electrical probes of scanning Kelvin probe force microscopy and scanning spreading resistance microscopy. With increasing bandgap, the potential imaging shows significant increases in both the large potential features due to extended defects or defect aggregations and the potential fluctuation due to unresolvable point defects with single or a few charges. The resistance imaging shows increases in both overall resistance and resistance nonuniformity due to defects in the subsurface region. These defects are expected to affect open-circuit voltage after the surfaces are turned to junction upon device completion.
Impact of carbon-fluorine doped titanium dioxide in the performance of an electrochemical sensing of dopamine and rosebengal sensitized solar cells
Authors: C Abinaya , Dinesh Bose , Sangari M. , Ramar A. , Umadevi M. , Mayandi J.
Published: January 2015

The role of Fluorine and Carbon as dopants in the TiO2 based electrochemical sensor and DSSC were presented in this work. A series of Carbon nano-cones and disc doped TiO2 (TC), Fluorine doped TiO2 (FT) and C & F co-doped TiO2 (CFT) powdered samples were prepared via solid state synthesis. The CFT film showed excellent electrochemical sensitivity to the oxidation of dopamine in aqueous solution and could be employed as a dopamine sensor. The proposed sensor exhibited good linear response in the range of 10-820 μM with a detection limit of 3.6 μM under optimum conditions. The photovoltaic performances of Rose Bengal sensitized solar cells were assessed through I-V measurements. The CFT based DSSC shows a short-circuit current density and a power conversion efficiency (η) of 0.908 mA/cm2 and 0.163% respectively, which is 35% and 38% greater than the performance of other PT based cells. The characterization studies such as UV-Visible spectroscopy, Photoluminescence, TEM and EPR spectroscopy were utilized for further investigation, which helps us to understand how fluorine and carbon play a part in dopamine sensing and solar energy conversion.
Governing through Civil Society? The Making of a Post-Soviet Political Subject in Ukraine
Authors: Vorbrugg Alexander
Published: January 2015

Drawing on ethnographic research, this study analyzes the work of a German political foundation in Ukraine. Departing from a governmentality perspective that closely examines concrete practices, I focus on the organization's attempts to establish itself as a political actor. This foundation aims to build more democratic political imaginations and open up different spaces for contestation. However, in both its rationalities and its practices, the foundation's project also (re)inscribes enclosures. It is both reflective and productive of boundaries between those who qualify as full political subjects, and others who do not, and claims a preformed knowledge of democracy and civil society. In examining situated and ambivalent claims to democracy and civil society—on the level of practices and beyond ‘classic’ liberal contexts of governance—this paper demonstrates that studies of governmentality provide analytical tools to shed light on subjects that have gained little attention in the field so far. It further contributes to a deeper understanding of what kinds of publics and political realities emerge in projects of ‘actually existing democratization’.
Repairing Australia's estuaries for improved fisheries production – what benefits, at what cost?
Authors: Creighton Colin , Boon Paul I. , Brookes Justin D. , Sheaves Marcus
Published: January 2015

An Australia-wide assessment of ~1000 estuaries and embayments undertaken by the National Land and Water Resources Audit of 1997–2002 indicated that ~30% were modified to some degree. The most highly degraded were in New South Wales, where ~40% were classified as ‘extensively modified’ and <10% were ‘near pristine’. Since that review, urban populations have continued to grow rapidly, and increasing pressures for industrial and agricultural development in the coastal zone have resulted in ongoing degradation of Australia's estuaries and embayments. This degradation has had serious effects on biodiversity, and commercial and recreational fishing. A business case is developed that shows that an Australia-wide investment of AU$350 million into repair will be returned in less than 5 years. This return is merely from improved productivity of commercial fisheries of a limited number of fish, shellfish and crustacean species. Estuary repair represents an outstanding return on investment, possibly far greater than most of Australia's previous environmental repair initiatives and with clearly demonstrated outcomes across the Australian food and services economies.