bluuebunny/crossref_metadata_2025 huggingface dataset:
The internalizing pathway to adolescent substance use disorders: Mediation by ruminative reflection and ruminative brooding
Authors: Adrian Molly , McCarty Carolyn , King Kevin , McCauley Elizabeth , Stoep Ann Vander
Published: August 2014

Two subtypes of rumination were examined in relationship to substance use and substance use disorders in adolescents. In the 8th and 9th grade, 521 adolescents completed measures assessing depressive symptoms, conduct problems, and reflective and brooding subtypes of rumination. In 12th grade, adolescents reported substance use and were administered the substance use disorders modules from the DISC. Path analyses conducted with data from 428 participants indicated that neither depression nor rumination variables significantly affected the presence of substance use. However, indirect effects of depression through reflection and brooding were differentially related to risk of developing substance use disorders, with brooding positively associated with Marijuana Use Disorders, and reflection negatively related to both Marijuana and Alcohol Use Disorders. Pathways did not differ by sex. These findings suggest that promoting self‐reflection may be an effective strategy to prevent and intervene with the development of problematic substance use.
Single night video‐game use leads to sleep loss and attention deficits in older adolescents☆
Authors: Wolfe Jasper , Kar Kellyann , Perry Ashleigh , Reynolds Chelsea , Gradisar Michael , Short Michelle A.
Published: August 2014

The present study investigated adolescent video‐game use prior to bedtime and subsequent sleep, working memory and sustained attention performance. Participants were 21 healthy, good‐sleeping adolescents (16 male) aged between 15 and 20 years (M = 17.6 years, SD = 1.8). Time spent video‐gaming and subsequent sleep was measured across one night in the sleep laboratory. There were significant correlations between time spent video‐gaming and sleep and between video‐gaming and sustained attention, but not working memory. Sleep duration, in turn, had a significant negative association with sustained attention performance. Mediation analyses revealed that the relationship between video‐gaming and sustained attention was fully mediated by sleep duration. These results indicate that video‐gaming affected the ability to sustain attention only in as much as it affected sleep. In order to minimise negative consequences of video‐game playing, video‐games should be used in moderation, avoiding use close to the sleep period, to obviate detriments to sleep and performance.
Los determinantes de la orientación exportadora y los resultados en las pymes exportadoras en Colombia
Authors: Escandón Barbosa Diana Marcela , Hurtado Ayala Andrea
Published: August 2014

Partiendo del concepto de orientación al mercado definido en el campo del marketing internacional, este artículo analiza los factores determinantes de la orientación exportadora y su influencia en los resulta- dos empresariales de las pymes exportadoras en Colombia. A partir de una encuesta realizada en 2011 a 297 pymes manufactureras colombianas, se estima un modelo de redes neuronales tipo perceptrón mul- ticapa para establecer la importancia de los determinantes de la orientación exportadora como factores que influyen en los resultados empresariales de las pymes exportadoras colombiana. Se concluye que la orientación emprendedora y la innovación son los factores determinantes de la orientación exportadora que más influyen en los resultados empresariales de las pymes en Colombia.
Red chlorophyll excitation dynamics in Arthrospira platensis photosystem I trimeric complexes as studied by femtosecond transient absorption spectroscopy
Authors: Kompanets Viktor , Shubin Vladimir , Terekhova Irina , Kotova Elena , Kozlovsky Vladimir , Novoderezhkin Vladimir , Chekalin Sergey , Karapetyan Navasard , Razjivin Andrei
Published: August 2014

Femtosecond absorption spectroscopy was applied to study for the first time excitation dynamics in isolated photosystem I trimers from Arthrospira platensis, which display extremely long‐wavelength absorption peaks. Pump–probe spectra observed at 77 K in the timescale of dozens of picoseconds upon 70‐fs excitation revealed two maxima near 710 and 730 nm, which correspond to red chlorophyll forms. Bleaching at 680 nm developed in ∼200 fs, whereas the bleaching kinetics at 710 and 730 nm exhibited two components with time constants of 1 and 5.5 ps. Comparison of the kinetics of bleaching development at 710 nm and 730 nm with that of bleaching decay at 680 nm indicated that both long‐wavelength forms of trimers are populated mainly via direct energy transfer from bulk chlorophyll.
MicroRNAs in the interaction between host and bacterial pathogens
Authors: Maudet Claire , Mano Miguel , Eulalio Ana
Published: August 2014

MicroRNAs (miRNAs) are small non‐coding RNAs with a central role in the post‐transcriptional control of gene expression, that have been implicated in a wide‐range of biological processes. Regulation of miRNA expression is increasingly recognized as a crucial part of the host response to infection by bacterial pathogens, as well as a novel molecular strategy exploited by bacteria to manipulate host cell pathways. Here, we review the current knowledge of bacterial pathogens that modulate host miRNA expression, focusing on mammalian host cells, and the implications of miRNA regulation on the outcome of infection. The emerging role of commensal bacteria, as part of the gut microbiota, on host miRNA expression in the presence or absence of bacterial pathogens is also discussed.
Molecular pathology – The value of an integrative approach
Authors: Salto-Tellez Manuel , James Jacqueline A. , Hamilton Peter W.
Published: August 2014

Molecular Pathology (MP) is at the heart of modern diagnostics and translational research, but the controversy on how MP is best developed has not abated. The lack of a proper model or trained pathologists to support the diagnostic and research missions makes MP a rare commodity overall.

Here we analyse the scientific and technology areas, in research and diagnostics, which are encompassed by MP of solid tumours; we highlight the broad overlap of technologies and analytical capabilities in tissue research and diagnostics; and we describe an integrated model that rationalizes technical know‐how and pathology talent for both. The model is based on a single, accredited laboratory providing a single standard of high‐quality for biomarker discovery, biomarker validation and molecular diagnostics.
Exact Analysis of Stress Fields in Composite Laminates under Extension
Authors: Liang W.-Y. , Tseng W.-D. , Tarn J.-Q.
Published: August 2014

Exact analysis of displacements and stresses in 2-D orthotopic laminates under extension is conducted. On the basis of the Hamiltonian state space approach and the transfer matrix method, a complete solution, in the context of generalized strain, which exactly satisfies the state space equation, the traction-free BC on the top and bottom surfaces of the rectangular section, the interfacial continuity conditions in multi-layered laminates, and the end conditions on free edges, is obtained by combing the eigensolutions and the particular solution. Evaluating of the stresses in the boundary layer for verification shows that the stress decay in laminates under uniform extension may be slow and the edge effects may be pronounced.
Thermal Postbuckling and Free Vibration of Extensible Microscale Beams Based on Modified Couple Stress Theory
Authors: Wang Y.-G. , Lin W.-H. , Zhou C.-L. , Liu R.-X.
Published: August 2014

This paper presents a mathematical model and a computational approach for the thermal post-buckling and free vibration in the vicinity of the buckled equilibrium position of microbeams based on the modified couple stress Euler-Bernoulli beam theory and geometrically accurate relation. The governing equations for the whole analysis are established with a intrinsic material length scale parameter to capture the size effect. These equations, in conjunction with the corresponding boundary conditions, are decomposed into two two-point boundary value problems, which are solved using the shooting method. For static deformation, the geometric nonlinearity is involved and the size dependent postbuckling configuration is obtained as a function of temperature rise. For dynamic one, the small amplitude free vibration about the prebuckled position is developed following an assumed harmonic time mode, and the length scale and temperature rise dependent fundamental natural frequency is presented. Numerical computations are executed to illustrate the size dependency in the thermal postbuckling behaviors and fundamental frequency of the vibration around the buckled configuration of microbeams.
Investigation on Hygro-Thermo-Mechanical Stress of a Plastic Electronic Package
Authors: Su F. , Li W.-J. , Lan T.-B. , Shang W.
Published: August 2014

Plastic packaging materials tend to absorb moisture from ambient environment and get swollen, this may raise hygro-stress in plastic electronic package and redistribute the internal stress. In this paper, we reviewed the dramatic deformation of a plastic package (Flip Chip Plastic Ball Grid Array-FCPBGA) due to moisture absorption first, then hygro-thermo-mechanical stress of the plastic package and its evolution during a period of three months were investigated with finite element method, user development was performed for this investigation. The finite element model was verified with hygro-thermal deformation of the FCPBGA measured with a 3-D moiré interferometry system. Following findings were obtained: A. Thermal stress field was changed a lot due to moisture absorption; B. Thermal stress of chip was released to some extent, but peal stress up to 62.2MPa occurred to the solder bump, thus the danger of Under Bump Metal (UBM) opening increased.
WMD, WMD, WMD: Securitisation through ritualised incantation of ambiguous phrases
Authors: OREN IDO , SOLOMON TY
Published: August 2014

We seek to reinvigorate and clarify the Copenhagen School's insight that ‘security’ is not ‘a sign that refers to something more real; the utterance [‘security’] itself is the act’. We conceptualise the utterances of securitising actors as consisting not in arguments so much as in repetitive spouting of ambiguous phrases (WMD, rogue states, ethnic cleansing). We further propose that audience acceptance consists not in persuasion so much as in joining the securitising actors in a ritualised chanting of the securitising phrase. Rather than being performed to, the audience participates in the performance in the manner in which a crowd at a rock concert sings along with the artists. We illustrate our argument with a discussion of how the ritualised chanting of the phrase ‘weapons of mass destruction’ during the run-up to the Iraq War ultimately produced the grave Iraqi threat that it purportedly described.
Protective genotypes in HIV infection reflect superior function of KIR3DS1+ over KIR3DL1+ CD8+ T cells
Authors: Zipperlen Katrin , Gallant Maureen , Stapleton Staci , Heath John , Barrett Lisa , Grant Michael
Published: August 2014

Certain human class I histocompatibility‐linked leukocyte antigen (HLA)/killer cell immunoglobulin‐like receptor (KIR) genotypic combinations confer more favourable prognoses upon exposure to human immunodeficiency virus (HIV). These combinations influence natural killer (NK) cell function, thereby implicating NK cells in protection from HIV infection or disease progression. Because CD8+ T cells restrict HIV replication, depend upon HLA class I antigen presentation and can also express KIR molecules, we investigated how these HLA/KIR combinations relate to the phenotype and function of CD8+ T cells from uninfected controls and individuals with chronic HIV infection. CD8+ T cells from KIR3DL1 and KIR3DS1 homozygous individuals, and expressing the corresponding KIR, were enumerated and phenotyped for CD127, CD57 and CD45RA expression. Ex vivo and in vitro responsiveness to antigen‐specific and polyclonal stimulation was compared between KIR‐expressing and non‐expressing CD8+ T cells by interferon‐γ production. There were higher numbers and fractions of KIR3DL1‐expressing CD8+ T cells in HIV‐infected individuals independent of HLA‐Bw4 co‐expression, whereas expansion of KIR3DS1‐expressing CD8+ T cells reflected HLA‐Bw4*80I co‐expression. KIR3DL1+ and S1+ CD8+ T cells were predominantly CD127−CD57+CD45RA+. KIR3DL1‐expressing CD8+ T cells were insensitive to ex vivo stimulation with peptides from HIV or common viruses, but responded to anti‐CD3 and recovered responsiveness to common viruses in vitro. Ex vivo non‐responsiveness of KIR3DL1‐expressing CD8+ T cells was also independent of HLA‐Bw4. KIR3DS1‐expressing T cells responded normally to ex vivo antigenic stimulation, illustrating functional superiority over KIR3DL1+ CD8+ T cells.
Direct determination of tannins in Acacia mearnsii bark using near-infrared spectroscopy
Authors: Menezes Caren Machado , Ben da Costa Adilson , Renner Ricardo Rocha , Bastos Lucas Ferreira , Ferrão Marco Flôres , Dressler Valderi Luiz
Published: August 2014

This study investigated the application of near-infrared spectroscopy (NIRS) and multivariate calibration methods to the direct determination of the tannin content inAcacia mearnsiibark to improve control during the tannin extraction process.
Reducible, dibromomaleimide-linked polymers for gene delivery
Authors: Tan James-Kevin Y. , Choi Jennifer L. , Wei Hua , Schellinger Joan G. , Pun Suzie H.
Published: August 2014

Reducible, dibromomaleimide-linked polycations exhibit reduced cytotoxicity compared to their non-degradable analogs and can be site-specifically functionalized.
Thermally-stable resistive switching with a large ON/OFF ratio achieved in poly(triphenylamine)
Authors: Zhang Wenbin , Wang Cheng , Liu Gang , Zhu Xiaojian , Chen Xinxin , Pan Liang , Tan Hongwei , Xue Wuhong , Ji Zhenghui , Wang Jun , Chen Yu , Li Run-Wei
Published: August 2014

Thermally stable poly(triphenylamine) (PTPA) has been used to achieve promising resistive switching memory devices with a large ON/OFF ratio.
A photoswitchable bis-azo derivative with a high temporal resolution
Authors: Garcia-Amorós Jaume , Reig Marta , Cuadrado Alba , Ortega Mario , Nonell Santi , Velasco Dolores
Published: August 2014

The novel photoswitchable bis-azo derivative reported herein shows a high temporal resolution of 2 × 108times between the thermal relaxation rates of its two constituting photochromes.
X-ray irradiation induced reduction and nanoclustering of lead in borosilicate glass
Authors: Stanley Halina B. , Banerjee Dipanjan , van Breemen Lambert , Ciston Jim , Liebscher Christian H. , Martis Vladimir , Merino Daniel Hermida , Longo Alessandro , Pattison Philip , Peters Gerrit W. M. , Portale Giuseppe , Sen Sabyasachi , Bras Wim
Published: August 2014

Under the influence of X-rays an unexpected formation of pure Pb nanoparticles was observed in PbS-doped borosilicate glass.
Influence of fluorine side-group substitution on the crystal structure formation of benzene-1,3,5-trisamides
Authors: Zehe Christoph , Schmidt Marko , Siegel Renée , Kreger Klaus , Daebel Venita , Ganzleben Sandra , Schmidt Hans-Werner , Senker Jürgen
Published: August 2014

The crystal structure of 1,3,5-tris(2-fluoro-2-methylpropionylamino)benzene was solved by combining powder X-ray diffraction, solid-state NMR spectroscopy and quantum chemical calculations.
Anomalous high adsorption energy of H2O on fluorinated graphenes: a first principles study
Authors: Wang Peng , Wang Hongtao , Yang Wei
Published: August 2014

A high adsorption energy of water has been unveiled on C4F via density functional theory studies, implying anomalous superhydrophilicity of C4F.
Nitrogen-doped carbon supports with terminated hydrogen and their effects on active gold species: a density functional study
Authors: Gu Junjie , Du Qian , Han You , He Zhenghua , Li Wei , Zhang Jinli
Published: August 2014

The stabilities of gold species on N-doped graphene increase with its valence state. Au2Cl6 interacts preferentially with HCl on N-doped supports, enhancing the stability of Au catalysts for acetylene hydrochlorination.
Towards the ionic limit of two-dimensional materials: monolayer alkaline earth and transition metal halides
Authors: Lin Shi-Hsin , Kuo Jer-Lai
Published: August 2014

We theoretically explored new two-dimensional materials near the ionic instability (three-dimensional structures are favored), with covalent bonded systems (graphene) sitting at the opposite end of the spectrum.
Carbon nanotube–fullerene hybrid nanostructures by C60 bombardment: formation and mechanical behavior
Authors: Yang Xueming , Wang Longjie , Huang Yanhui , Han Zhonghe , To Albert C.
Published: August 2014

Carbon nanotube–fullerene hybrid nanostructures formed by C60 bombardment.
A PtRu catalyzed rechargeable oxygen electrode for Li–O2 batteries: performance improvement through Li2O2 morphology control
Authors: Yang Yao , Liu Wei , Wang Yingming , Wang Xiaochen , Xiao Li , Lu Juntao , Zhuang Lin
Published: August 2014

The Li–O2 cell performance can be improved by controlling the Li2O2 morphology during discharge by the Pt2Ru/C catalyst.
Electrochemical in battery polymerization of poly(alkylenedioxythiophene) over lithium iron phosphate for high-performance cathodes
Authors: Cíntora-Juárez Daniel , Pérez-Vicente Carlos , Ahmad Shahzada , Tirado José Luis
Published: August 2014

Molecular wiring concept in LiFePO4 cathodes by in battery polymerization.
Density functional studies on (NCH)n azagraphane: activated surface for organocatalysis
Authors: Marutheeswaran S. , Pancharatna Pattath D. , Balakrishnarajan Musiri M.
Published: August 2014

The reactive surface of azagraphane formed by alternate nitrogen substitution on graphane contains the basic nitrogen as well as the activated C–H with hydridic nature owing to the anomeric effect.
Distinguishable Zn(ii) and Pb(ii) template effects on forming pendant-armed Schiff-base macrocyclic complexes including a remarkable Pb(ii)–π macrocyclic complex
Authors: Zhang Kun , Geng Jiao , Jin Chao , Huang Wei
Published: August 2014

36-Membered [2 + 2] dinuclear Zn(ii) and 18-membered [1 + 1] mononuclear Pb(ii) Schiff-base macrocyclic complexes have been described, including a unique intramolecular η3-coordinated Pb(ii)–π macrocyclic complex obtained under ambient conditions.
Electrochemistry of well-defined graphene samples: role of contaminants
Authors: Patten Hollie V. , Velický Matěj , Clark Nick , Muryn Christopher A. , Kinloch Ian A. , Dryfe Robert A. W.
Published: August 2014

We report the electrochemical characterisation of well-defined graphene samples, prepared by mechanical exfoliation. Mechanical exfoliation is the method of choice for high purity graphene samples, despite the inherent complexity of the approach and the small scale of the resultant flakes. However, one important, yet presently unclear area, is the role of adsorbates such as processing residue, on the properties of the graphene layer. We report high resolution microscopic and electrochemical characterisation of a variety of poly(methyl methacrylate) (PMMA) transferred graphene samples, with the explicit aim of investigating the relationship between electrochemical activity and sample purity.
Disruptive photon technologies for chemical dynamics
Authors: Chapman Henry N.
Published: August 2014

A perspective of new and emerging technologies for chemical dynamics is given, with an emphasis on the use of X-ray sources that generate sub-picosecond pulses. The two classes of experimental techniques used for time-resolved measurements of chemical processes and their effects are spectroscopy and imaging, where the latter includes microscopy, diffractive imaging, and crystallography. X-Ray free-electron lasers have brought new impetus to the field, allowing not only temporal and spatial resolution at atomic time and length scales, but also bringing a new way to overcome limitations due to perturbation of the sample by the X-ray probe by out-running radiation damage. Associated instrumentation and methods are being developed to take advantage of the new opportunities of these sources. Once these methods of observational science have been mastered it should be possible to use the new tools to directly control those chemical processes.
Ex situ evaluation of the composition of protein corona of intravenously injected superparamagnetic nanoparticles in rats
Authors: Sakulkhu Usawadee , Maurizi Lionel , Mahmoudi Morteza , Motazacker Mahdi , Vries Marcel , Gramoun Azza , Ollivier Beuzelin Marie-Gabrielle , Vallée Jean-Paul , Rezaee Farhad , Hofmann Heinrich
Published: August 2014

The proteins adsorbed onto SPION coated with PVA with different charges showed surprisingly different behaviorsin situandex situ.
Rhodium-catalyzed olefination of aryl tetrazoles via direct C–H bond activation
Authors: Wang Liang , Wu Wenting , Chen Qun , He Mingyang
Published: August 2014

Rh(iii)-catalyzed direct olefination reaction via aromatic C–H bond activation is described using tetrazole as the directing group.
Study of a novel gel electrolyte based on poly-(methoxy/hexadecyl-poly(ethylene glycol) methacrylate) co-polymer plasticized with 1-butyl-3-methylimidazolium tetrafluoroborate
Authors: Wang Long , Zhu Hua-jun , Zhai Wei , Cai Feng , Liu Xiao-min , Yang Hui
Published: August 2014

Compared with traditional liquid electrolytes, solid polymer electrolytes possess higher reliability and safety but lower ionic conductivity, which can be improved by incorporating plasticizers to form gel polymer electrolytes (GPEs).
Inclusion complexes synthesized from an ABA triblock polymer and β-cyclodextrins: amplification of hydrophobic interaction along a hydrophilic polymer chain
Authors: Gao Jiangang , Yu Shaobo , Zheng Benpei , Song Qingping , Peng Xingxing , Lin Ying , Zou Gang , Zhang Qijin
Published: August 2014

β-CD can accommodate PEG segments in aqueous solution through a hydrophobic stabilizing and hydrogen-bond inducing effect.
Production of pure potassium salts directly from sea bittern employing tartaric acid as a benign and recyclable K+ precipitant
Authors: Ghara Krishna Kanta , Korat Nikunja , Bhalodia Dixita , Solanki Jignesh , Maiti Pratyush , Ghosh Pushpito K.
Published: August 2014

Climatic uncertainties and shortage of land expose conventional potash production from sea bittern to greater risks which the proposed route helps mitigate.
A dual model logic gate for mercury and iodide ions sensing based on metal–organic framework MIL-101
Authors: Fang Jing Mei , Gao Peng Fei , Hu Xiao Li , Li Yuan Fang
Published: August 2014

In this work, by the introduction of metal–organic framework MIL-101 as the fluorescence anisotropy (FA) amplification and the low background platform, we firstly employed FA as the output signal of a logic gate, and constructed a dual model INHIBIT logic gate for Hg2+and I−detection.
A high performance xylose microbial fuel cell enabled by Ochrobactrum sp. 575 cells
Authors: Li Xin , Zhong Guo-Zhen , Qiao Yan , Huang Jing , Hu Wei Hua , Wang Xing-Guo , Li Chang Ming
Published: August 2014

A new bacterium, Ochrobactrum sp. 575, is applied as a high performance MFC while resolving xylose, and the formation of fumaric acid is observed during the discharging process.
Self-assembled zirconia nanotube arrays: fabrication mechanism, energy consideration and optical activity
Authors: Amer Ahmad W. , Mohamed Seifallah M. , Hafez Ahmed M. , AlQaradawi Siham Y. , Aljaber Amina S. , Allam Nageh K.
Published: August 2014

We present a comprehensive roadmap for the precise control of the dimensions and optical properties of anodically fabricated zirconia nanotubes.
Synthesis, structure, and catalytic activities of new Cu(i) thiocarboxylate complexes
Authors: Joshi Deepak Kumar , Mishra Kunj Bihari , Tiwari Vinod Kumar , Bhattacharya Subrato
Published: August 2014

Newly synthesized Cu(i) with thiobenzoate complexes was found to catalyse the regioselective synthesis of glycoconjugate triazoles under click reaction.
Facile and economical synthesis for “plum pudding”-shaped porous LiFePO4/carbon composites for lithium ion batteries
Authors: Xue Hairong , Zhao Jianqing , Wang Tao , Guo Hu , Fan Xiaoli , He Jianping
Published: August 2014

The LiFePO4/C composite shows plentiful LiFePO4 nanospheres uniformly lodged in the 3D porous conductive carbon framework, and exhibits improved electrochemical performance.
Morphology and dopant-dependent optical characteristics of novel composite 1D and 3D-based heterostructures of CdSe nanocrystals and LaPO4:Re (Re = Eu, Ce, Tb) metal phosphate nanowires
Authors: Han Jinkyu , Wang Lei , Wong Stanislaus S.
Published: August 2014

Observation of morphology and dopant dependent optical behavior in novel quantum dot-metal oxide-based heterostructures.
Synthesis gas production from bio-oil: steam reforming of ethanol as a model compound
Authors: Pavlova S. , Yaseneva P. , Sadykov V. , Rogov V. , Tikhov S. , Bespalko Yu. , Belochapkine S. , Ross J.
Published: August 2014

Syngas production via ethanol steam reforming has been studied over solid Ru/Ce0.5Zr0.5O2 and alumina supported Ru/Ce0.4Zr0.4Sm0.2O2 as granulated and monolithic catalysts.
Biosynthesis approach to nitrogen doped graphene by denitrifying bacteria CFMI-1
Authors: Zhu Chunlin , Feng Zhangqi , Fan Mengmeng , Chen Chuntao , Ma Bo , Yang Jiazhi , Sun Dongping
Published: August 2014

A facile and biosynthetic microbial method to produce N-doped graphene nanosheets is described.
Dissipative particle dynamics study of nano-encapsulated thermal energy storage phase change material
Authors: Rao Zhonghao , You Xinyu , Huo Yutao , Liu Xinjian
Published: August 2014

The nano-encapsulated phase change materials (PCM), which have several good thermophysical properties, were proposed as potential for thermal energy storage.
Cobalt-based compounds and composites as electrode materials for high-performance electrochemical capacitors
Authors: Lee Kian Keat , Chin Wee Shong , Sow Chorng Haur
Published: August 2014

Recent progress, achievements, challenges and outlook in the (re)search of high performance cobalt-based compounds and composites for electrochemical capacitors.
Electrospun chitosan–polyvinyl alcohol composite nanofibers loaded with cerium for efficient removal of arsenic from contaminated water
Authors: Sharma Reena , Singh Nahar , Gupta Ashish , Tiwari Sangeeta , Tiwari Sandeep Kumar , Dhakate Sanjay R.
Published: August 2014

Cerium-PVA/CHT nanofibers prepared through electrospinning technique have demonstrated 80% removal of Arsenic from contaminated water within the initial 10 minutes.
N-substituted amine-borane ionic liquids as fluid phase, hydrogen storage materials
Authors: Rekken B. D. , Carre-Burritt A. E. , Scott B. L. , Davis B. L.
Published: August 2014

Ionic liquids incorporating an amine-borane functionality can remain liquid below −20 °C and remain liquid after H2 release.
Nickel nanoparticles immobilized on three-dimensional nitrogen-doped graphene as a superb catalyst for the generation of hydrogen from the hydrolysis of ammonia borane
Authors: Mahyari Mojtaba , Shaabani Ahmad
Published: August 2014

Nickel nanoparticles immobilized on three-dimensional nitrogen-doped graphene-based frameworks (NiNPs@3D-(N)GFs) were synthesized and examined for hydrogen generation from the hydrolytic dehydrogenation of ammonia borane.
A graphene-based electrochemical filter for water purification
Authors: Liu Yanbiao , Dustin Lee Juen Hon , Xia Qing , Ma Ying , Yu Yang , Lanry Yung Lin Yue , Xie Jianping , Ong Choon Nam , Vecitis Chad D. , Zhou Zhi
Published: August 2014

A novel graphene-based electrochemical filter with carbon nanotubes as conductive binders was developed for water purification.
Dual‐band balun with flexible frequency ratios
Authors: Li Shen Andres , Zhou Mi , Arigong Bayaner , Shao Jin , Ren Han , Ding Jun , Zhou Rongguo , Zhang Hualiang
Published: August 2014

A novel dual‐band balun is presented. The designed 3‐port balun is based on a 4‐port structure with the fourth port terminated as an open end. Being a 4‐port symmetrical network, even–odd‐mode analysis is used to analyse the balun's performance. Based on the derived explicit design equations, a balun is designed to operate at 1.1 and 2 GHz. Numerical simulations show a low reflection coefficient S11, equal magnitude of −3 dB as well as 180° phase difference at the output ports. To validate the theoretical and numerical simulations, the proposed balun is fabricated on the FR4 Isola printed circuit board and measurement results match well with the design theory.
Improved binary‐weighted split‐capacitive‐array DAC for high‐resolution SAR ADCs
Authors: Li Y. , Lian Y.
Published: August 2014

An improved split‐capacitive‐array digital‐to‐analogue converter (DAC) with an optimised segmentation degree (i.e. the number of bits in the most significant bit (MSB) sub‐array) is proposed to reduce the area, the switching power consumption and improve the linearity compared to a conventional binary‐weighted (CBW) capacitive‐array DAC and a conventional binary‐weighted split‐capacitive‐array with an attenuation capacitor (BWA) DAC. The presented analysis considers the area and the power dissipation from the DAC as well as the analogue‐to‐digital converter's (ADC's) dynamic performance to determine the optimum segmentation degree for the proposed split‐capacitive‐array DAC and the BWA DAC. Using the minimum matching requirement for the unit capacitor in a 12‐bit CBW DAC, the proposed split‐capacitive‐array DAC with an MSB:LSB = 8:4 segmentation reduces the input capacitance by 2× and reduces the switching power by 15× compared to the 12‐bit CBW DAC. It also improves the ADC's dynamic performance and reduces the switching power by 3.75× compared to the conventional 12‐bit BWA DAC with an MSB:LSB = 10:2 segmentation.
Spectrum‐sharing broadcast channels using fountain codes: energy, delay and throughput
Authors: Yang Yuli , Aïssa Sonia
Published: August 2014

In this study, the authors develop a transmission protocol for cognitive radio networks, whereby fountain codes are exploited in the broadcast channels and secondary users help with the broadcast from the base station (BS) to primary users (PUs). With fountain codes, the BS broadcasts to the secondary transmitter (ST) as well as PUs simultaneously, and stops broadcasting once the ST has received sufficient codeword to decode the original information reliably. Then, the ST will resume the broadcasting to PUs until all of them can decode the original information successfully. While broadcasting, the ST transmits information over its own link, that is, to the secondary receiver, based on dirty paper coding technique. As such, the energy expenditure at the BS is reduced and, moreover, secondary links have more opportunities to access the licensed spectrum band. To evaluate the performance of the developed scheme, they analyse its energy expenditure, broadcast time as well as the throughput over secondary links, and achieve the corresponding closed‐form expressions. Compared with the traditional broadcast protocol without the secondary's help, illustrative numerical results substantiate the validity of the author's derivations, which also demonstrate the efficiency of the developed scheme both on the energy savings and on the spectrum utilisation.
A new cumulant estimator in multipath fading channels for digital modulation classification
Authors: Liu Pei , Shui Peng‐Lang
Published: August 2014

In this study, the authors consider the problem of digital modulation classification in a multipath channel using the cumulant‐based method. A new estimator is proposed to estimate the fourth‐order cumulant of transmitted symbol in a multipath channel with the help of the fourth‐order cross‐cumulants of the received symbols. The proposed estimator does not need the estimation of the multipath channel coefficients and is shown to be asymptotically unbiased. The channel order is an important factor to affect the estimator. The impact of the channel order mismatch on the estimator is analysed and it is proved that the estimator keeps unbiased in the case of the overestimation of the channel order. The simulated experiments are made to verify the cumulant‐based classifier using the new estimator and the results show that it attains better performance for digital modulation classification than the two existing cumulant‐based classifiers in a multipath channel.
Improved localisation method based on multi‐hop distance unbiased estimation
Authors: Wei Quanrui , Zhong Dexing , Han Jiuqiang
Published: August 2014

Range‐free, distributed localisation method is a challenging issue in wireless sensor networks (WSN). Typical hop count‐based localisation methods assume that the Hopsize for different hop count is the same. However, many observations in WSN indicate that this assumption does not always correspond to the practical situation. In this study, the authors propose an approximate distribution of k‐hop node distance and derive the expectation of k‐hop node distance under the above distribution. Furthermore, the authors propose a novel range‐free localisation method based on the multi‐hop distance unbiased estimation (MDUE), and the simulation results demonstrate that more accurate distance and localisation can be obtained by MDUE than the state‐of‐the‐art methods.
Distributed input and state estimation for non‐linear discrete‐time systems with direct feedthrough
Authors: Ding Jinglin , Xiao Jian , Zhang Yong
Published: August 2014

This study investigates the problem of distributed estimation for non‐linear system of sensor networks with unknown inputs affecting both the system state and outputs. A novel ‘information filtering algorithm’ is derived by reconstructing the non‐linear version of the extended recursive three‐step filter (NERTSF) into the information filter architecture, which simultaneously estimates the state and the unknown input, denoted as non‐linear version of the extended recursive three‐step information filter (NERTSIF). Afterwards the information filter is extended to the ‘derivative‐free’ version with the help of the cubature Kalman filter (CKF) according to the linear error propagation methodology. A distributed filtering algorithm, based on the derivative‐free version of the NERTSIF is proposed in which each sensor node only fuses the local observation instead of the global information and updates the local information state and matrix from its neighbours’ estimates using the dynamic average‐consensus strategy. The efficacy of the proposed distributed algorithm is demonstrated by simulation examples on target tracking problem and is compared with existing algorithms such as centralised fusion filter and distributed CKF, which lack in tracking the true dynamics of the unknown input.
Linear time‐varying control of the vibrations of flexible structures
Authors: Zidane Imed , Marinescu Bogdan , Abbas‐Turki Mohamed
Published: August 2014

Recent results on pole placement for linear time‐varying (LTV) systems are exploited here for the control of flexible structures. The infinite‐dimensional system is approached as usual by a restricted number of modes of interest, according to the frequency range in which the system is exploited. The difference with the previous approaches (e.g. gain scheduling) is that only one finite dimension linear model is used and its parameters (frequency and damping of the modes) are varying according to the operating conditions. The control model is thus LTV and a regulator is analytically synthesised to ensure closed‐loop stability and performances. This regulator is also LTV and thus automatically (without any special switching action) tracks the operating conditions of the system. The case of a flexible beam is studied in simulation as well as in the laboratory experimentation. Hence, a suitable application of the proposed LTV synthesis is done to find a compromise between the complexity of interpolation and its efficiency. Furthermore, the bad dissipation factor of flexible systems leads them to be good candidates to proof the efficiency of the proposed gain scheduling strategy. This work validates on a real system the LTV pole placement approach and opens the way to a new gain scheduling strategy for the control of LTV, non‐linear or infinite‐dimensional systems.
Consensus of delayed multi‐agent systems by reduced‐order observer‐based truncated predictor feedback protocols
Authors: Zhou Bin
Published: August 2014

For high‐order linear multi‐agent systems with large input and communication delays, a predictor feedback approach is established to design reduced‐order observer‐based output feedback protocols. This approach can compensate arbitrarily large delays but will lead to infinite dimensional protocols. Under the assumption that the open‐loop dynamics is at most polynomially unstable, the proposed predictor feedback protocols is truncated by removing the distributed terms, resulting in a finite dimensional reduced‐order observer‐based output feedback protocols, which will be referred to as truncated predictor feedback (TPF) protocols. Compared with the predictor feedback protocols, the main advantage of the TPF protocols is that it is very easy to implement. Two numerical examples are worked out to demonstrate the effectiveness of the proposed approaches.
New results on stability analysis and stabilisation of networked control system
Authors: Li Zhicheng , Alsaadi Fuad , Hayat Tasawar , Gao Huijun
Published: August 2014

This study studies the problems of stability analysis and stabilisation for networked control systems. The networked control system is modelled as a Markovian jump time‐delay system, which is transformed into an interconnected form by the transformation approach. Then, the new stability and the stabilisation conditions are presented based on the scaled small gain theorem and the Lyapunov functional method. The results are much less conservative than other existing results because of the utilisation of the input–output method and some novel techniques. In the illustrated example, the controller of mechanical networked control systems is obtained by the stabilisation condition, which illustrates the less conservatism and effectiveness of the authors’ method.
Recursive source localisation by time difference of arrival sensor networks with sensor position uncertainty
Authors: Qu Xiaomei , Xie Lihua
Published: August 2014

In a passive sensor network, time difference of arrival (TDOA) measurements are often exploited for source localisation. The extended Kalman filter (EKF) is usually used for source localisation in a mobile sensor network; however, its performance is limited because of the non‐linearity of the TDOA in relation to the source position. Especially when the available sensor positions include uncertainties, accurate localisation becomes much more challenging. To improve the localisation performance, this study develops two linear recursive three‐dimensional source localisation algorithms by taking into consideration the random sensor position noises. An illustrative example is given to demonstrate that the proposed linear recursive localisation algorithms outperform the EKF localisation algorithm. Performance comparison between the two proposed algorithms is also provided.
Stochastic adaptive event‐triggered control and network scheduling protocol co‐design for distributed networked systems
Authors: Xu Hao , Sahoo Avimanyu , Jagannathan Sarangapani
Published: August 2014

In a distributed ‘networked control system’ (NCS), multiple physical systems or agents are connected to their corresponding controllers through a shared packet‐switched communication network. For such distributed NCS, periodic sampled controller design is unsuitable to handle packet‐switched closed‐loop control systems and a novel stochastic optimal adaptive event‐sampled controller scheme is proposed in the application layer for each physical system or agent expressed as an uncertain linear dynamic system. Lyapunov stability analysis will be utilised to derive the event trigger condition. In addition, a network scheduling protocol is also required for such NCS. Traditional network scheduling protocols are unsuitable for such NCS since the behaviour of the physical systems is disregarded during the protocol design. Therefore in this study, a novel distributed network scheduling protocol via cross‐layer approach is developed to improve the performance of distributed NCS by minimising an overall system cost function which consists of the information collected from both the event‐triggered controller for each physical system in the application layer and the distributed scheduling protocol from the network layer. It will be demonstrated that the proposed co‐design approach will not only allocate the network resources efficiently but also it will improve the performance of the overall distributed NCS. Simulation results are included to demonstrate the effectiveness of the proposed cross‐layer co‐design.
Complex waveguide filter topologies employing inductive windows and dielectric objects
Authors: Martínez‐Mendoza Mónica , Cañete‐Rebenaque David , Alvarez‐Melcon Alejandro , Cameron Richard
Published: August 2014

This study presents novel topologies for implementing bandpass elliptic filters employing waveguide structures composed of inductive windows and dielectric objects. Cavities operating in dual mode are obtained by placing a dielectric post inside a cavity. By combining dual mode with single mode cavities, several useful filter responses implementing transmission zeros can be synthesised. The first proposed structure is a three‐pole filter with one transmission zero, using a physically asymmetric configuration with two waveguide cavities and one dielectric post. The second proposed structure implements a four‐pole filter with one transmission zero, employing a physically symmetric configuration with one dielectric post and three waveguide cavities. The third structure implements two transmission zeros in a four‐pole filter, also employing a symmetric structure, but now with two dielectric posts and two cavities. Important aspects on sensitivity issues of the new structures, as well as on synthesis techniques, needed to obtain the required topologies, are introduced. This includes several alternatives to implement a transfer function, using physically symmetric or asymmetric structures. Finally, a transversal filter with one dual‐mode cavity using a dielectric post has been manufactured and tested with good results. This is the first time that this type of filters is experimentally demonstrated.
Single‐phase ac–dc–ac multilevel five‐leg converter
Authors: Norões Maia Ayslan Caisson , Jacobina Cursino Brandão
Published: August 2014

In this study, a multilevel five‐leg single‐phase ac–dc–ac converter and its generalisation are presented. The converter is suitable to be used as an uninterrupted power supply or a unified power quality conditioner without an isolation transformer. The operating principles, the pulse‐width modulation strategy and the control system for the proposed converter are presented. The proposed single‐phase multilevel ac–dc–ac converter is composed mostly of low‐power switches capable of generating input and output voltages with low harmonic content. The proposed configuration is compared with the conventional solution in terms of harmonic distortion, semiconductor losses and ratings of switches. Experimental results demonstrate the feasibility of the proposed configuration. The experimental verification of the proposed topology and control strategy was obtained by using IGBTs with dedicated drives and a digital signal processor TMS320F28335 with plug‐in boards and sensors.
Way of operation to improve performance for advanced split‐gate resurf stepped oxide UMOSFET
Authors: Wang Ying , Hu Hai‐Fan , Dou Zheng , Yu Cheng‐Hao
Published: August 2014

In this study, a way of operating a double split‐gate resurf stepped oxide (DSGRSO) UMOS has been proposed. The n‐drift region is divided into two parts by the double split‐gate: the upper one and the lower one, which enhances the resurf active effect and binges in an electric field peak in the middle of the n‐drift region, and decreases the width of split‐gate trench, resulting in an increase of figure of merit (FOM). The simulation results show that the DSGRSO UMOS has improved the saturated breakdown voltage by 25.7% and FOM by 108% as compared with SGRSO UMOS at the certain aspect ratio.
Optimised geometry model for liquid‐suspended miniature gyroscope
Authors: Zhang Haifeng , Chen Nan , Liu Xiaowei , Yin Liang , Li Hai
Published: August 2014

The levitation of the rotor eliminates mechanical friction and obtains high sensitivity for miniature gyroscopes. However, it is difficult to control the rotor stability because of the rotor's small size. A novel liquid‐suspended rotor miniature gyroscope is proposed, whose stability is improved by liquid suspension. The magnetic and flow field models of the miniature gyroscope are established. Based on models, the driving torque and viscous torque were analysed to optimise the structures of the driving stator and the rotor. The optimised stator structure is 6‐phase‐12‐coil, the optimised rotor radius is 7.44 mm, and the maximum rotational speed of the rotor of 11 210 rpm.
Polarimetry diagnostic on OMEGA EP using a 10-ps, 263-nm probe beam
Authors: Davies A. , Haberberger D. , Boni R. , Ivancic S. , Brown R. , Froula D. H.
Published: August 2014

A polarimetry diagnostic was built and characterized for magnetic-field measurements in laser-plasma experiments on the OMEGA EP laser. This diagnostic was built into the existing 4ω (263-nm) probe system that employs a 10-ps laser pulse collected with an f/4 imaging system. The diagnostic measures the rotation of the probe beam's polarization. The polarimeter uses a Wollaston prism to split the probe beam into orthogonal polarization components. Spatially localized intensity variations between images indicate polarization rotation. Magnetic fields can be calculated by combining the polarimetry data with the measured plasma density profile obtained from angular filter refractometry.
Effect of asymmetrical eddy currents on magnetic diagnosis signals for equilibrium reconstruction in the Sino-UNIted Spherical Tokamak
Authors: Jiang Y. Z. , Tan Y. , Gao Z. , Wang L.
Published: August 2014

The vacuum vessel of Sino-UNIted Spherical Tokamak was split into two insulated hemispheres, both of which were insulated from the central cylinder. The eddy currents flowing in the vacuum vessel would become asymmetrical due to discontinuity. A 3D finite elements model was applied in order to study the eddy currents. The modeling results indicated that when the Poloidal Field (PF) was applied, the induced eddy currents would flow in the toroidal direction in the center of the hemispheres and would be forced to turn to the poloidal and radial directions due to the insulated slit. Since the eddy currents converged on the top and bottom of the vessel, the current densities there tended to be much higher than those in the equatorial plane were. Moreover, the eddy currents on the top and bottom of vacuum vessel had the same direction when the current flowed in the PF coils. These features resulted in the leading phases of signals on the top and bottom flux loops when compared with the PF waveforms.