bluuebunny/crossref_metadata_2025 huggingface dataset:
The Surveillance Legacies of 9/11: Recalling, Reflecting on, and Rethinking Surveillance in the Security Era
Authors: Lyon David , Haggerty Kevin D.
Published: October 2014

Do we need yet more analysis of the responses to the September 11, 2001 (hereafter 9/11), terrorist attacks? Those tragic events occurred more than a decade ago, and their 10-year memorial focused on bringing “closure” to the event. For many, those attacks have become an increasingly distant, if still poignant, memory. For still others—such as the new cohort of undergraduate students who were only nine years old on the day of the attacks—9/11 is social history.

Our contention in putting together this volume is that there continues to be significant reason to scrutinize 9/11 in terms of its consequences for the dynamics of surveillance. The aftermath of that tragic event played a major role in policy changes and in international relations. Wars were fought in Iraq and Afghanistan, sparked by 9/11, and many thousands more people died as a result. “National security” was elevated to a top priority in the United States and elsewhere, and this approach has had wave and ripple effects throughout the world. This is the “War on Terror,” and, unlike other wars, this one has no visible end point. These developments certainly affected surveillance practices internationally and have been the cue for the United States to demand that other countries fall in line with its approach. On the other hand, for many countries, especially in the global south, 9/11 is not a top-of-mind matter, nor is “national security” a vital concern.
On the consequences of bilingualism: We need language and the brain to understand cognition
Authors: KROLL JUDITH F.
Published: October 2014

In the last two decades there has been an explosion of research on bilingualism and its consequences for the mind and the brain (e.g., Kroll & Bialystok, 2013). One reason is that the use of two or more languages reveals interactions across cognitive and neural systems that are often obscured in monolingual speakers of a single language (e.g., Kroll, Dussias, Bogulski & Valdes Kroff, 2012). From this perspective, the interest in bilingualism is about developing a platform to ask questions about the ways that cognitive and neural networks are engaged during language use, in different learning environments, and across the lifespan. Another reason is that an emerging body of research on the consequences of bilingualism suggests that language experience changes cognition and the brain (e.g., Abutalebi, Della Rosa, Green, Hernandez, Scifo, Keim, Cappa & Costa, 2012; Bialystok, Craik, Green, & Gollan, 2009). Some of these changes have been claimed to produce cognitive advantages (see Bialystok et al., for a review of bilingual advantages and disadvantages).
Effects of Preheating and Cooling Durations on Roll-to-Roll Hot Embossing
Authors: Kim Seyoung , Son Youngsu , Park Heechang , Kim Byungin , Yun Dongwon
Published: October 2014

In this study, we examined the sensitivity of embossed pattern depth to preheat supply and cooling and investigated how the pattern type and density affect the embossed depth. The main factors that affect embossed pattern qualities of roll-to-roll hot embossing, such as roller temperature, roller speed, and applied force, were determined using the response surface methodology. Eight conditions were then added to determine the time-dependent effects of heat transfer with custom-designed preheating and cooling systems. An extended preheat time for the polymethylmethacrylate substrate contributed to the significant change in the embossed depth, whereas the substrate-cooling did not exhibit a clear increasing or decreasing trend. Larger embossed depths were achieved in the horizontal patterns with lower density than in the vertical patterns, and the lower pattern densities showed greater embossed depths in most embossing conditions. We expect that this result will help to understand the effects of the pre- and posttreatment of roll-to-roll hot embossing by employing time duration factors of heat transfer, depending on the mold pattern type and density.
Replica Extraction Method on Nanostructured Gold Coatings and Orientation Determination Combining SEM and TEM Techniques
Authors: Bocker Christian , Kracker Michael , Rüssel Christian
Published: October 2014

In the field of electron microscopy the replica technique is known as an indirect method and also as an extraction method that is usually applied on metallurgical samples. This contribution describes a fast and simple transmission electron microscopic (TEM) sample preparation by complete removal of nanoparticles from a substrate surface that allows the study of growth mechanisms of nanostructured coatings. The comparison and combination of advanced diffraction techniques in the TEM and scanning electron microscopy (SEM) provide possibilities for operators with access to both facilities. The analysis of TEM-derived diffraction patterns (convergent beam electron diffraction) in the SEM/electron backscatter diffraction software simplifies the application, especially when the patterns are not aligned along a distinct zone axis. The study of the TEM sample directly by SEM and transmission Kikuchi diffraction allows cross-correlation with the TEM results.
A NOTE ON STEADY FLOW INTO A SUBMERGED POINT SINK
Authors: HOCKING G. C. , FORBES L. K. , STOKES T. E.
Published: October 2014

The steady, axisymmetric flow induced by a point sink (or source) submerged in an unbounded inviscid fluid is computed. The resulting deformation of the free surface is obtained, and a limit of steady solutions is found that is quite different to those obtained in past work. More accurate solutions indicate that the old limiting flow rate was too high and, in fact, the breakdown of steady solutions at a lower flow rate is characterized by the appearance of spurious wavelets at the free surface.
Molecular evidence of digestion and absorption of epibiotic bacterial community by deep-sea crab Shinkaia crosnieri
Authors: Watsuji Tomo-o , Yamamoto Asami , Motoki Kaori , Ueda Kenji , Hada Emi , Takaki Yoshihiro , Kawagucci Shinsuke , Takai Ken
Published: October 2014

The hydrothermal vent crab Shinkaia crosnieri is considered to obtain nutrition from the epibiotic bacteria found on the setae, but previous studies have not shown how nutrients can be transferred from the epibionts to the host. In this study, microscopic observations of S. crosnieri intestinal components detected autofluorescent setae fragments and pigmentation derived from the digestion of epibionts in a dye-stained epibiont tracer experiment. An in vitro digestion experiment with epibiotic populations using an intestinal extract demonstrated the degradation of epibiotic cells by digestive enzymes. A phylogenetic analysis showed that many of the bacterial 16S ribosomal RNA gene sequences obtained from the intestine were closely related to the sequences of the epibionts, thus they were probably derived from the epibionts. A stable isotope tracer experiment also indicated that 13C assimilated by the epibionts provided a carbon (nutrition) source for the host. Both activity measurements and isotope studies showed that chemosynthetic metabolism by the gut microbial components were inactive. Together with the feeding behaviour of living S. crosnieri, these results indicate that S. crosnieri ingests the epibionts using maxillipeds and assimilates them via its digestive organs as a nutrient source. The results of this study elucidate the mechanism of nutritional transfer in ectosymbiosis between chemosynthetic bacteria and deep-sea invertebrates.
A scaling law for random walks on networks
Authors: Perkins Theodore J. , Foxall Eric , Glass Leon , Edwards Roderick
Published: October 2014

The dynamics of many natural and artificial systems are well described as random walks on a network: the stochastic behaviour of molecules, traffic patterns on the internet, fluctuations in stock prices and so on. The vast literature on random walks provides many tools for computing properties such as steady-state probabilities or expected hitting times. Previously, however, there has been no general theory describing the distribution of possible paths followed by a random walk. Here, we show that for any random walk on a finite network, there are precisely three mutually exclusive possibilities for the form of the path distribution: finite, stretched exponential and power law. The form of the distribution depends only on the structure of the network, while the stepping probabilities control the parameters of the distribution. We use our theory to explain path distributions in domains such as sports, music, nonlinear dynamics and stochastic chemical kinetics.
Hyaluronic acid–polypyrrole nanoparticles as pH-responsive theranostics
Authors: Park Dongjin , Cho Youngnam , Goh Sung-Ho , Choi Yongdoo
Published: October 2014

Doxorubicin-loaded hyaluronic acid–polypyrrole nanoparticles as smart theranostic agents for proliferating macrophages.
Pt/C trapped in activated graphitic carbon layers as a highly durable electrocatalyst for the oxygen reduction reaction
Authors: Nie Yao , Chen Siguo , Ding Wei , Xie Xiaohong , Zhang Yun , Wei Zidong
Published: October 2014

A nitrogen-doped graphitic carbon layer was elaborately introduced into the Pt/C surface so that Pt NPs could survive the pyrolyzation.
A facile synthesis of small-sized and monodisperse hexagonal NaYF4:Yb3+,Er3+ nanocrystals
Authors: Li Dongdong , Shao Qiyue , Dong Yan , Jiang Jianqing
Published: October 2014

Small-sized (∼11.86 nm) hexagonal NaYF4:Yb3+,Er3+ nanocrystals have been synthesized by simultaneously controlling the nucleation and growth process.
Enantioselective synthesis of arylglycine derivatives by direct C–H oxidative cross-coupling
Authors: Wei Xiao-Hong , Wang Gang-Wei , Yang Shang-Dong
Published: October 2014

A new method for the synthesis of chiral α-amino acid derivatives by enantioselective C–H arylation of N-aryl glycine esters with aryl boric acids by direct C–H oxidative cross-coupling has been performed. This work successfully integrates the direct C–H oxidation with asymmetric arylation and exhibits excellent enantioselectivity.
A folic acid conjugated silica–titania porous hollow nanosphere for improved topical photodynamic therapy
Authors: Jang Yoonsun , Kim Sojin , Oh Wan-Kyu , Kim Chanhoi , Lee Inkyu , Jang Jyongsik
Published: October 2014

The folic acid conjugated hollow nanosphere is used to encapsulate protoporphyrin IX and is utilized for photodynamic therapy.
Reactivity of a Ru(iii)–hydroxo complex in substrate oxidation in water
Authors: Ohzu Shingo , Ishizuka Tomoya , Kotani Hiroaki , Kojima Takahiko
Published: October 2014

A mononuclear RuIII–OH complex oxidizes substrates such as hydroquinones in water through a pre-equilibrium process based on adduct formation by hydrogen bonding between the RuIII–OH complex and the substrates. The reaction mechanism switches from hydrogen atom transfer to electron transfer depending on the oxidation potential of substrates.
Hydrogen bonded-extended lanthanide coordination polymers decorated with 2,3-thiophenedicarboxylate and oxalate: synthesis, structures, and properties
Authors: Li Zhao-Hao , Xue Li-Ping , Shan Li-Li , Zhao Bang-Tun , Kan Jian , Su Wei-Ping
Published: October 2014

Five new LnCPs decorated with H2tdc and oxalate mixed ligands exhibit a 2D sql layer structure, then the 2D layers are further linked by intermolecule hydrogen bonds to form a 3D supramolecular network with sxb topology.
Rotationally resolved water dimer spectra in atmospheric air and pure water vapour in the 188–258 GHz range
Authors: Serov E. A. , Koshelev M. A. , Odintsova T. A. , Parshin V. V. , Tretyakov M. Yu.
Published: October 2014

Millimeter wave spectra of the water dimer under the conditions close to the atmospheric ones in pure water vapour and its mixture with air are detected and quantitatively analyzed.
The photo-orientation of azobenzene in viscous solutions, simulated by a stochastic model
Authors: Cantatore Valentina , Granucci Giovanni , Persico Maurizio
Published: October 2014

Simulations of the photo-orientation of azobenzene in a viscous solvent, based on nonadiabatic dynamics results, highlight the role of photoisomerization.
The mutual interactions based on amphipathic tetraoxacalix[2]arene[2]triazine: recognition cases of anion and cation investigated by a computational study
Authors: Li Zhi-Feng , Li Hui-Xue , Yang Xiao-Ping
Published: October 2014

This work provides insights into the interaction nature of amphiphilic tetraoxacalix[2]arene[2]triazine with the system (J. Am. Chem. Soc., 2013, 135, 892) as well as the recognition cases of anion and cation.
The vibrational relaxation of NO in Ar: tunneling in a curve-crossing mechanism
Authors: Dashevskaya E. I. , Nikitin E. E. , Troe J.
Published: October 2014

A qualitative reaction-coordinate picture of the nonadiabatic tunneling vibronic relaxation NO(X2Π, v = 1) + Ar → NO(X2Π, v = 0) + Ar at low temperatures.
Investigation of PF6− and TFSI− anion intercalation into graphitized carbon blacks and its influence on high voltage lithium ion batteries
Authors: Qi Xin , Blizanac Berislav , DuPasquier Aurelien , Meister Paul , Placke Tobias , Oljaca Miodrag , Li Jie , Winter Martin
Published: October 2014

At high potentials of >4.5 V vs. Li/Li+, graphitic structures in carbon black can provide host sites for the partially reversible intercalation of electrolyte salt anions. To avoid this reaction, the graphitization degree of carbon blacks must be optimized.
P,C-bond cleavage in the ligand sphere of a nickel(ii) complex
Authors: Walg Simon P. , Schmidt Alexandra D. , Schmitz Marcus , Farsadpour Saeid , Lang Johannes , Niebergall Mark , Sun Yu , Roesky Peter W. , Niedner-Schatteburg Gereon , Thiel Werner R.
Published: October 2014

P,C-bond cleavage at a pyrimidinyl ligand results in a pentacoordinate nickel(ii) complex coordinated by a carbanionic ligand.
Spiers Memorial Lecture : Organic electronics: an organic materials perspective
Authors: Wudl Fred
Published: October 2014

This Introductory Lecture is intended to provide a background to Faraday Discussion 174: “Organic Photonics and Electronics” and will consist of a chronological, subjective review of organic electronics. Starting with “ancient history” (1888) and history (1950–present), the article will take us to the present. The principal developments involved the processes of charge carrier generation and charge transport in molecular solids, starting with insulators (photoconductors) and moving to metals, to semiconductors and ending with the most popular semiconductor devices, such as organic light-emitting diodes (OLEDs), organic field effect transistors (OFETs) and organic photovoltaics (OPVs). The presentation will be from an organic chemistry/materials point of view.
Electroless nickel coated nano-clay for electrolytic removal of Hg(ii) ions
Authors: Arora Rajat , Singh Nitesh , Balasubramanian K. , Alegaonkar Prashant
Published: October 2014

The footprint existence and accumulation of cataclysmic Hg(ii) ions in aqueous media poses a severe threat to biological ecosystems and necessitates immediate measures for its regulation.
Characterization of Li-doped WO3nanowires and their enhanced electrocatalytic oxidation of ascorbic acid
Authors: Mu Wanjun , Xie Xiang , Zhang Rui , Li Xingliang , Lv Kai , Yu Qianhong , Wei Hongyuan , Jian Yuan
Published: October 2014

Li-doped WO3nanowires have been hydrothermally prepared and characterized mainlyviaspectroscopic methods.
Preparation and characterization of TiO2–Graphene@Fe3O4 magnetic composite and its application in the removal of trace amounts of microcystin-LR
Authors: Liang Yulu , He Xiwen , Chen Langxing , Zhang Yukui
Published: October 2014

A facile and feasible approach is presented to prepare a novel magnetic photocatalyst TiO2–graphene@Fe3O4 composite exhibiting a superior performance in the removal of trace microcystin-LR in water samples.
Cyclophosphazene–organostannoxane hybrid motifs in polymeric and molecular systems
Authors: Kundu Subrata , Mohapatra Chandrajeet , Chandrasekhar Vadapalli
Published: October 2014

The synthesis and structural characterization of two hybrid inorganic ring systems that contain interconnected cyclophosphazene–stannoxane motifs are reported.
Simple synthesis of bimetallic alloyed Pd–Au nanochain networks supported on reduced graphene oxide for enhanced oxygen reduction reaction
Authors: Zhang Qian-Li , Feng Jin-Xia , Wang Ai-Jun , Wei Jie , Feng Jiu-Ju
Published: October 2014

A simple and rapid wet-chemical co-reduction method was developed for synthesis of alloyed Pd–Au nanochain networks supported on RGO, with the assistance of caffeine as a capping agent and a structure directing agent.
Rhodium(i)-catalysed “ene-type” cycloisomerization of N-[2-(2-alkyn-1-yl)phenyl]carbodiimides leading to 3-(cis-alken-1-yl)-2-aminoquinolines
Authors: Otani Takashi , Onishi Misato , Seino Takafumi , Furukawa Naoki , Saito Takao
Published: October 2014

cis-Selective 3-(1-alkenyl)quinoline synthesis via rhodium catalyzed cycloisomerization has been developed.
Facile phase transfer of gold nanoparticles from aqueous solution to organic solvents with thiolated poly(ethylene glycol)
Authors: Alkilany A. M. , Yaseen A. I. Bani , Park J. , Eller J. R. , Murphy C. J.
Published: October 2014

A simple approach for the efficient transfer of large gold nanoparticles from water to organic solvents using thiolated poly(ethylene glycol) as a phase transfer agent is presented.
Power‐aware hiding method for S‐box protection
Authors: Ma Jiangsha , Li Xiangyu , Wang Moyang
Published: October 2014

A power analysis attack countermeasure, called power‐awareness‐based hiding, is proposed. It is effective in implementing nonlinear operations, S‐boxes, in cryptographic algorithms. An advanced encryption standard (AES) S‐box circuit has been implemented in this approach using the Domino logic array style. The post‐layout simulation results show that the power‐aware hiding AES S‐box achieves a delay of 1.56 ns and a mean power consumption of 3.57 mW. The proposed method improves the power delay product by 65%, the normalised energy deviation by 43% and the normalised standard deviation by 30% compared to other secure methods.
Composite kernels conditional random fields for remote‐sensing image classification
Authors: Wu Junfeng , Jiang Zhiguo , Luo Jianwei , Zhang Haopeng
Published: October 2014

The problem of classifying a remote‐sensing image by specifically labelling each pixel in the image is addressed. A novel method, named composite kernels conditional random field (CKCRF), which embeds multiple kernels into a classical CRFs model is proposed. Rather than manually selecting kernel‐like KCRF, CKCRFs chooses the appropriate kernel by training. Moreover, a genetic programming‐based decision‐level fusion framework is proposed to tackle the problem of feature selection. It can select the appropriate features suitable to each category. Evaluations show that CKCRFs outperform CRFs and KCRFs, and CKCRFs with the fusion scheme is better than that without the fusion step.
Continuous fine‐grained arm action recognition using motion spectrum mixture models
Authors: Zhao Xi , Gao Zhiming , Feng Tao , Shah Shishir , Shi Weidong
Published: October 2014

Motion sensors in smart wristbands/watches have been widely used to sense users’ level of movement and animation. Some studies have further recognised activity contexts using these sensors, such as walking, sitting and running. However, in applications requiring understanding of more complex activities such as interactions with other people or objects, it is necessary to recognise the fine‐grained arm action during user interactions with other people or objects. A method to recognise a set of arm actions on a fine‐grained level (e.g. checking the wristband, drinking water etc.) is proposed. Motion signals from the accelerometer and gyroscope are transformed into the frequency domain using the short‐time Fourier transform. Then, the action patterns are represented by the motion spectrum mixture model and action dynamics are modelled by continuous density hidden Markov models. Tested on a dataset collected from 23 subjects, the method shows satisfying performance and efficiency.
Renewable energy sources for complete optimal power system black‐start restoration
Authors: El‐Zonkoly Amany Mohamed
Published: October 2014

Integration of renewable energy sources (RESs) may increase the risk of power system blackouts because of the uncertainty nature of their output power. In the meantime, RESs have relatively short starting time when compared with non‐black start (BS) generating units. For this reason, RES needs to participate in power system restoration after blackouts. For a complete power system restoration, three stages must be completed. These stages are: generation restoration, transmission system restoration and load pick up. To achieve a faster restoration process, an optimal schedule for the BS units to crank the non‐BS (NBS) units is required with optimal transmission path selection. In addition, to maintain the stability of the system and satisfy the system operational constraints, an optimal load pick‐up sequence is required. In this study, the firefly algorithm (FA) is used to find the optimal final sequence of NBS units restoration, transmission paths and load pick‐up sequence with and without the aid of RES in the system. The objective is to minimise the overall restoration time and the unserved load which maximise the energy capability and improve the sustainability of the system. The proposed algorithm is applied successfully to the IEEE 39‐bus system.
A two‐level voltage source inverter with differentially sinusoidal pulse width modulation used in the interconnection system of a wind turbine generator
Authors: Charalampidis Alexandros C. , Chaniotis Antonios E. , Kladas Antonios G.
Published: October 2014

This study analyses an interconnection system based on differentially sinusoidal pulse width modulation, used for the interconnection to the grid of a variable speed wind turbine. The modulation technique used provides specific advantages in comparison with the commonly used sinusoidal pulse width modulation (SPWM) technique, such as lower DC bus voltage requirements, smaller switching losses for the same switching frequency as well as less higher harmonic content in the voltage waveforms produced. The respective control system is also described in detail. Thus this study provides a guide enabling the design of any interconnection system based on this modulation technique.
Generalised relations between P ‐ and Y ‐matrices and their applications
Authors: Guerra‐Pulido Jaime Octavio , Pérez‐Alcázar Pablo Roberto
Published: October 2014

The P ‐matrix is commonly used to analyse surface acoustic waves (SAW) elements such as the interdigital transducer (IDT) but, when some IDTs are connected through their acoustic ports, their frequency response could be calculated easily in terms of their admittances. Instead of the P ‐matrix, Y ‐matrix also allows coupling of the system to another electric or electronic device. Here, the authors present a general method to obtain the Y ‐matrix (with size N × N) of a SAW device with N electrical terminals connected to N different voltage sources. This method considers the reflections from the edges or any other non‐electrical elements that can cause reflections beyond P ‐matrices. In addition, it has been shown that when there are no reflections and there are two P ‐matrices, this method converges to well‐known previous results. Furthermore, the authors present two cases that could be used to analyse a SAW device: the input admittance and the equivalent P ‐matrix for a SAW device when a Y ‐matrix is connected to the electrical port of the SAW device. Also, the authors have calculated the acoustic relations for two SAW devices connected through their electric ports. Furthermore, these methods are exemplified through their application to a SAW system composed of three different IDTs and to an IDT and an inductor connected to its electrical port.
Composition profiling of GaAs/AlGaAs quantum dots grown by droplet epitaxy
Authors: Bocquel J. , Giddings A. D. , Mano T. , Prosa T. J. , Larson D. J. , Koenraad P. M.
Published: October 2014

Droplet epitaxy (DE) is a growth method which can create III-V quantum dots (QDs) whose optoelectronic properties can be accurately controlled through the crystallisation conditions. In this work, GaAs/AlGaAs DE-QDs have been analyzed with the complimentary techniques of cross-sectional scanning tunneling microscopy and atom probe tomography. Structural details and a quantitative chemical analysis of QDs of different sizes are obtained. Most QDs were found to be pure GaAs, while a small proportion exhibited high intermixing caused by a local etching process. Large QDs with a high aspect ratio were observed to have an Al-rich crown above the GaAs QD. This structure is attributed to differences in mobility of the cations during the capping phase of the DE growth.
Variational integration for ideal magnetohydrodynamics with built-in advection equations
Authors: Zhou Yao , Qin Hong , Burby J. W. , Bhattacharjee A.
Published: October 2014

Newcomb's Lagrangian for ideal magnetohydrodynamics (MHD) in Lagrangian labeling is discretized using discrete exterior calculus. Variational integrators for ideal MHD are derived thereafter. Besides being symplectic and momentum-preserving, the schemes inherit built-in advection equations from Newcomb's formulation, and therefore avoid solving them and the accompanying error and dissipation. We implement the method in 2D and show that numerical reconnection does not take place when singular current sheets are present. We then apply it to studying the dynamics of the ideal coalescence instability with multiple islands. The relaxed equilibrium state with embedded current sheets is obtained numerically.
Variations of boundary reaction rate and particle size on the diffusion-induced stress in a phase separating electrode
Authors: Zhang Lei , Song Yicheng , He Linghui , Ni Yong
Published: October 2014

In contrast to the case of single-phase delithiation wherein faster discharging leads to higher diffusion-induced stress (DIS), this paper reports nonmonotonous dependency of the boundary reaction rate on the DIS in nanosized spherical electrode accompanying phase separation. It is attributed to a transition from two-phase to single-phase delithiation driven by increase of the boundary reaction rate leading to narrowing and vanishing of the miscibility gap in a range of the particle size. The profiles of lithium concentration and the DIS are identified during the transition based on a continuum model. The resultant maximum DIS first decreases in the region of two-phase delithiation and later returns to increase in the region of single-phase delithiation with the increase of the boundary reaction rate. A map for the failure behavior in the spherical electrode particle is constructed based on the Tresca failure criterion. These results indicate that the failure caused by the DIS can be avoided by appropriate selection of the said parameters in such electrodes.
A serial-kinematic nanopositioner for high-speed atomic force microscopy
Authors: Wadikhaye Sachin P. , Yong Yuen Kuan , Reza Moheimani S. O.
Published: October 2014

A flexure-guided serial-kinematic XYZ nanopositioner for high-speed Atomic Force Microscopy is presented in this paper. Two aspects influencing the performance of serial-kinematic nanopositioners are studied in this work. First, mass reduction by using tapered flexures is proposed to increased the natural frequency of the nanopositioner. 25% increase in the natural frequency is achieved due to reduced mass with tapered flexures. Second, a study of possible sensor positioning in a serial-kinematic nanopositioner is presented. An arrangement of sensors for exact estimation of cross-coupling is incorporated in the proposed design. A feedforward control strategy based on phaser approach is presented to mitigate the dynamics and nonlinearity in the system. Limitations in design approach and control strategy are discussed in the Conclusion.
Note: Reliable and non-contact 6D motion tracking system based on 2D laser scanners for cargo transportation
Authors: Kim Young-Keun , Kim Kyung-Soo
Published: October 2014

Maritime transportation demands an accurate measurement system to track the motion of oscillating container boxes in real time. However, it is a challenge to design a sensor system that can provide both reliable and non-contact methods of 6-DOF motion measurements of a remote object for outdoor applications. In the paper, a sensor system based on two 2D laser scanners is proposed for detecting the relative 6-DOF motion of a crane load in real time. Even without implementing a camera, the proposed system can detect the motion of a remote object using four laser beam points. Because it is a laser-based sensor, the system is expected to be highly robust to sea weather conditions.
Structural, compositional, and photoluminescence characterization of thermal chemical vapor deposition-grown Zn3N2 microtips
Authors: Wei Pai-Chun , Tong Shih-Chang , Tseng Chuan-Ming , Chang Chung-Chieh , Hsu Chia-Hao , Shen Ji-Lin
Published: October 2014

The catalytic growth of Zn3N2 using guided-stream thermal chemical vapor deposition has been investigated within the parameter range of acicular growth to obtain uniform microtips with a high crystalline quality. The cubic anti-bixbyite crystal structure of Zn3N2 microtips and its related phonon mode are revealed by X-ray diffraction and Raman spectroscopy, respectively. The surface morphologies of pure and surface-oxidized Zn3N2 microtips are depicted by scanning electron microscopy and show the crack formation on the surface-oxidized Zn3N2 microtips. The spatial element distribution map confirms the VLS growth mechanism for Zn3N2 microtips and reveals the depth profile of zinc, nitrogen, oxygen, and nickel elements. Photoluminescence (PL) spectra of Zn3N2 microtips show a sharp infrared band-to-band emission peak at 1.34 eV with a full width at half maximum of ∼100 meV and a very broad oxygen-related defect band emission peak centered at ∼0.85 eV.
Electron-hole recombination on ZnO(0001) single-crystal surface studied by time-resolved soft X-ray photoelectron spectroscopy
Authors: Yukawa R. , Yamamoto S. , Ozawa K. , Emori M. , Ogawa M. , Yamamoto Sh. , Fujikawa K. , Hobara R. , Kitagawa S. , Daimon H. , Sakama H. , Matsuda I.
Published: October 2014

Time-resolved soft X-ray photoelectron spectroscopy (PES) experiments were performed with time scales from picoseconds to nanoseconds to trace relaxation of surface photovoltage on the ZnO(0001) single crystal surface in real time. The band diagram of the surface has been obtained numerically using PES data, showing a depletion layer which extends to 1 μm. Temporal evolution of the photovoltage effect is well explained by a recombination process of a thermionic model, giving the photoexcited carrier lifetime of about 1 ps at the surface under the flat band condition. This lifetime agrees with a temporal range reported by the previous time-resolved optical experiments.
Electric transport through perovskite La(Fe,Ga)O3 nanowires formed by electrospinning
Authors: Moon Taeho , Lee Won-Yong , Choi Chel-Jong , Yoon Jong-Won
Published: October 2014

Orthoferrite perovskite LaFeO3 has been of great interest with its versatility for potential applications in electromagnetic, catalytic, and sensing applications. Nanowires have shown great potential as active building blocks for assembling a variety of nanoscale devices, nevertheless far less is known about the characteristics of LaFeO3 nanowires. Here, we show that LaFeO3 nanowires with Ga doping can be produced by electrospinning, yielding the formation of specific nanostructure of fine crystallite array arranged along nanowire framework. The structure and chemical state analyses were performed to reveal the nanostructural difference induced by Ga substitution. Furthermore, the La(Fe,Ga)O3 nanowire devices were built and showed the temperature and field dependence on electric transport following the Poole-Frenkel conduction model. The dramatic conductance lowering by Ga doping was observed and explained by the change in trap energy for carrier hopping.
Low driving voltage simplified tandem organic light-emitting devices by using exciplex-forming hosts
Authors: Zhou Dong-Ying , Cui Lin-Song , Zhang Ying-Jie , Liao Liang-Sheng , Aziz Hany
Published: October 2014

Tandem organic light-emitting devices (OLEDs), i.e., OLEDs containing multiple electroluminescence (EL) units that are vertically stacked, are attracting significant interest because of their ability to realize high current efficiency and long operational lifetime. However, stacking multiple EL units in tandem OLEDs increases driving voltage and complicates fabrication process relative to their standard single unit counterparts. In this paper, we demonstrate low driving voltage tandem OLEDs via utilizing exciplex-forming hosts in the EL units instead of conventional host materials. The use of exciplex-forming hosts reduces the charge injection barriers and the trapping of charges on guest molecules, resulting in the lower driving voltage. The use of exciplex-forming hosts also allows using fewer layers, hence simpler EL configuration which is beneficial for reducing the fabrication complexity of tandem OLEDs.
Video-rate terahertz electric-field vector imaging
Authors: Takai Mayuko , Takeda Masatoshi , Sasaki Manabu , Tachizaki Takehiro , Yasumatsu Naoya , Watanabe Shinichi
Published: October 2014

We present an experimental setup to dramatically reduce a measurement time for obtaining spatial distributions of terahertz electric-field (E-field) vectors. The method utilizes the electro-optic sampling, and we use a charge-coupled device to detect a spatial distribution of the probe beam polarization rotation by the E-field-induced Pockels effect in a ⟨110⟩-oriented ZnTe crystal. A quick rotation of the ZnTe crystal allows analyzing the terahertz E-field direction at each image position, and the terahertz E-field vector mapping at a fixed position of an optical delay line is achieved within 21 ms. Video-rate mapping of terahertz E-field vectors is likely to be useful for achieving real-time sensing of terahertz vector beams, vector vortices, and surface topography. The method is also useful for a fast polarization analysis of terahertz beams.
Coherent phonon study of (GeTe)l(Sb2Te3)m interfacial phase change memory materials
Authors: Makino Kotaro , Saito Yuta , Fons Paul , Kolobov Alexander V. , Nakano Takashi , Tominaga Junji , Hase Muneaki
Published: October 2014

The time-resolved reflectivity measurements were carried out on the interfacial phase change memory (iPCM) materials ([(GeTe)2(Sb2Te3)4]8 and [(GeTe)2(Sb2Te3)1]20) as well as conventional Ge2Sb2Te5 alloy at room temperature and above the RESET-SET phase transition temperature. In the high-temperature phase, coherent phonons were clearly observed in the iPCM samples while drastic attenuation of coherent phonons was induced in the alloy. This difference strongly suggests the atomic rearrangement during the phase transition in iPCMs is much smaller than that in the alloy. These results are consistent with the unique phase transition model in which a quasi-one-dimensional displacement of Ge atoms occurs for iPCMs and a conventional amorphous-crystalline phase transition takes place for the alloy.
Selective engineering of cavity resonance for frequency matching in optical parametric processes
Authors: Lu Xiyuan , Rogers Steven , Jiang Wei C. , Lin Qiang
Published: October 2014

We propose to selectively engineer a single cavity resonance to achieve frequency matching for optical parametric processes in high-Q microresonators. For this purpose, we demonstrate an approach, selective mode splitting (SMS), to precisely shift a targeted cavity resonance, while leaving other cavity modes intact. We apply SMS to achieve efficient parametric generation via four-wave mixing in high-Q silicon microresonators. The proposed approach is of great potential for broad applications in integrated nonlinear photonics.
1.9 W continuous-wave single transverse mode emission from 1060 nm edge-emitting lasers with vertically extended lasing area
Authors: Miah M. J. , Kettler T. , Posilovic K. , Kalosha V. P. , Skoczowsky D. , Rosales R. , Bimberg D. , Pohl J. , Weyers M.
Published: October 2014

High-brightness edge-emitting semiconductor lasers having a vertically extended waveguide structure emitting in the 1060 nm range are investigated. Ridge waveguide (RW) lasers with 9 μm stripe width and 2.64 mm cavity length yield highest to date single transverse mode output power for RW lasers in the 1060 nm range. The lasers provide 1.9 W single transverse mode optical power under continuous-wave (cw) operation with narrow beam divergences of 9° in lateral and 14° (full width at half maximum) in vertical direction. The beam quality factor M2 is less than 1.9 up to 1.9 W optical power. A maximum brightness of 72 MWcm−2sr−1 is obtained. 100 μm wide and 3 mm long unpassivated broad area lasers provide more than 9 W optical power in cw operation.
Giant magnetoelectric effect in nonlinear Metglas/PIN-PMN-PT multiferroic heterostructure
Authors: Staruch M. , Li J. F. , Wang Y. , Viehland D. , Finkel P.
Published: October 2014

In this paper, we demonstrate high converse magnetoelectric (ME) coupling in a Metglas/Pb(In1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT) laminated ME composite by exploiting stress and field induced reversible ferroelectric-ferroelectric phase transitions in a relaxor ferroelectric single crystal. The approach exploits large transformational strain induced by low applied electric field in a PIN-PMN-PT crystal that was mechanically stressed close to a rhombohedral to orthorhombic phase transformation. The ME coefficient was enhanced by an order of magnitude as compared to the linear piezoelectric regime, with a maximum value of 1.3 × 10−7 s m−1 in non-resonant mode. This phenomenon can thus be exploited to provide improvements in the development of ME devices and magnetic sensors.
Charge transport in zirconium doped anatase nanowires dye-sensitized solar cells: Trade-off between lattice strain and photovoltaic parameters
Authors: Archana P. S. , Gupta Arunava , Yusoff Mashitah M. , Jose Rajan
Published: October 2014

Zirconium (Zr) is doped up to 5 at. % in anatase TiO2 nanowires by electrospinning and used as working electrode in dye-sensitized solar cells. Variations observed in the photovoltaic parameters were correlated by electrochemical impedance spectroscopy, open circuit voltage decay, and X-ray diffraction measurements. Results show that homovalent substitution of Zr in TiO2 increased the chemical capacitance and electron diffusion coefficient which in turn decreased charge transport resistance and charge transit time. However, lattice strain due to size mismatch between the Zr4+ and Ti4+ ions decreased open circuit voltage and fill factor thereby setting a trade-off between doping concentration and photovoltaic properties.
Design and characterization of ultra-stretchable monolithic silicon fabric
Authors: Rojas J. P. , Arevalo A. , Foulds I. G. , Hussain M. M.
Published: October 2014

Stretchable electronic systems can play instrumental role for reconfigurable macro-electronics such as distributed sensor networks for wearable and bio-integrated electronics. Typically, polymer composite based materials and its deterministic design as interconnects are used to achieve such systems. Nonetheless, non-polymeric inorganic silicon is the predominant material for 90% of electronics. Therefore, we report the design and fabrication of an all silicon based network of hexagonal islands connected through spiral springs to form an ultra-stretchable arrangement for complete compliance to highly asymmetric shapes. Several design parameters are considered and their validation is carried out through finite element analysis. The fabrication process is based on conventional microfabrication techniques and the measured stretchability is more than 1000% for single spirals and area expansions as high as 30 folds in arrays. The reported method can provide ultra-stretchable and adaptable electronic systems for distributed network of high-performance macro-electronics especially useful for wearable electronics and bio-integrated devices.
Permanent hydrophilization of outer and inner surfaces of polytetrafluoroethylene tubes using ambient air plasma generated by surface dielectric barrier discharges
Authors: Pavliňák D. , Galmiz O. , Zemánek M. , Brablec A. , Čech J. , Černák M.
Published: October 2014

We present an atmospheric pressure ambient air plasma technique developed for technically simple treatment of inner and/or outer surfaces of plastic tubes and other hollow dielectric bodies. It is based on surface dielectric barrier discharge generating visually diffuse plasma layers along the treated dielectric surfaces using water-solution electrodes. The observed visual uniformity and measured plasma rotational and vibrational temperatures of 333 K and 2350 K indicate that the discharge can be readily applied to material surface treatment without significant thermal effect. This is exemplified by the obtained permanent surface hydrophilization of polytetrafluoroethylene tubes related to the replacement of a high fraction (more than 80%) of the surface fluorine determined by X-ray photoelectron spectroscopy. A tentative explanation of the discharge mechanism based on high-speed camera observations and the discharge current and voltage of measurements is outlined.
Realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect
Authors: Ling Xiaohui , Yi Xunong , Zhou Xinxing , Liu Yachao , Shu Weixing , Luo Hailu , Wen Shuangchun
Published: October 2014

We report the realization of tunable spin-dependent splitting in intrinsic photonic spin Hall effect. By breaking the rotational symmetry of a cylindrical vector beam, the intrinsic vortex phases that the two spin components of the vector beam carries, which is similar to the geometric Pancharatnam-Berry phase, are no longer continuous in the azimuthal direction, and leads to observation of spin accumulation at the opposite edge of the beam. Due to the inherent nature of the phase and independency of light-matter interaction, the observed photonic spin Hall effect is intrinsic. Modulating the topological charge of the vector beam, the spin-dependent splitting can be enhanced and the direction of spin accumulation is switchable. Our findings may provide a possible route for generation and manipulation of spin-polarized photons, and enables spin-based photonics applications.
Design and Synthesis of Piperazine-Based Task-Specific Ionic Liquids for Liquid–Liquid Extraction of CuII, NiII, and CoII from Water
Authors: Xu Weiyuan , Wang Liang , Huang Jianying , Ren Gerui , Xu Dandan , Tong Haihe
Published: October 2014

The novel synthesis of task-specific ionic liquids (TSILs) introducing piperazine substructures was described. Piperazine functional groups were easily grafted onto an imidazolium cationic derivative via a simple four-step process starting from available materials such as imidazole, ethylene glycol, and 1-butylamine or 3-dimethylaminopropylamine. Effects of pH, temperature, and structure of functional groups on the performance of liquid–liquid extraction of Cu2+, Ni2+, and Co2+ from water were investigated. It was found that TSILs were efficient for removal of these metal ions in mild acid solutions. The TSIL with an extra nitrogen atom showed a higher capability to separate metal ions, especially for Cu2+. This may be ascribed to the intrinsic structure of the functional groups – the more coordination sites, the higher the affinity for the metal ions. Furthermore, the thermodynamics indicated that the extraction process was exothermic and spontaneous in nature.
Age-based demography of the glacier lanternfish (Benthosema glaciale) in the Flemish Cap
Authors: García-Seoane E. , Fabeiro M. , Silva A. , Meneses I.
Published: October 2014

It is important to understand the population dynamics of myctophids for a better understanding of the functioning of the ecosystem. In this work, age-based demography parameters of glacier lanternfish (Benthosema glaciale (Reinhardt, 1837)) were calculated. This study was based on 1213 individuals collected in the Flemish Cap during June–July 2008 and 2010. Ages were estimated from counts of annuli in the whole otolith. A strong relationship was found between both diameters of the otolith and fish length, and between otolith weight and increment number. Males predominated in 2008 (37.6% were females) whereas no differences from the expected sex ratio of 1:1 were observed in 2010. The somatic growth of B. glaciale is quite fast for the first three years and decreasing thereafter. The von Bertalanffy growth curves revealed interannual differences and no sexual dimorphism in growth. The instantaneous natural mortality coefficient, M, was 0.65 year–1 for the overall population. The maximum age recorded was 7. Our results were compared with age-based demographic parameters from previous studies in the Flemish Cap and in other regions. Because myctophids are considered opportunistic strategists, changes in their demographic features may reflect shifts in the ecosystem.
Structural complexity and turbidity do not interact to influence predation rate and prey selectivity by a small visually feeding fish
Authors: Figueiredo Bruno R. S. , Mormul Roger P. , Benedito Evanilde
Published: October 2014

Structural complexity and turbidity decrease predation by respectively providing a physical and visual refuge for prey. It is still unclear how the covariance between these variables could drive predation and prey selectivity. We experimentally simulated scenarios that are temporally observed in floodplain rivers. In the experiments, we crossed different prey types, structural complexity and turbidity. We hypothesised that the negative relationship between structural complexity and predation would become stronger with a linear increase in the turbidity level and that an increase in structural complexity and in turbidity would change prey selectivity from a selective to a random pattern. Our results showed that the effects of structural complexity and turbidity on predation may not covary; a linear increase in turbidity did not significantly change the patterns of predation or prey selectivity. In contrast, structural complexity significantly reduced prey consumption according to prey size. We argue that areas with low macrophyte cover may provide an efficient refuge for smaller prey, whereas an efficient refuge for larger prey can be attained only in areas with high macrophyte cover. In highly complex habitats, specificity in prey consumption is precluded because both prey species can hide amid the interstices of the macrophytes, leading to random prey selectivity.