bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-Dimensional Carbon Allotropes Comprising Phenyl Rings and Acetylenic Chains in sp+sp2 Hybrid Networks
Authors: Wang Jian-Tao , Chen Changfeng , Li Han-Dong , Mizuseki Hiroshi , Kawazoe Yoshiyuki
Published: April 2016

We here identify by ab initio calculations a new type of three-dimensional (3D) carbon allotropes that consist of phenyl rings connected by linear acetylenic chains in sp+sp2 bonding networks. These structures are constructed by inserting acetylenic or diacetylenic bonds into an all sp2-hybridized rhombohedral polybenzene lattice, and the resulting 3D phenylacetylene and phenyldiacetylene nets comprise a 12-atom and 18-atom rhombohedral primitive unit cells in the "Equation missing" symmetry, which are characterized as the 3D chiral crystalline modification of 2D graphyne and graphdiyne, respectively. Simulated phonon spectra reveal that these structures are dynamically stable. Electronic band calculations indicate that phenylacetylene is metallic, while phenyldiacetylene is a semiconductor with an indirect band gap of 0.58 eV. The present results establish a new type of carbon phases and offer insights into their outstanding structural and electronic properties.
Fast and single-step immunoassay based on fluorescence quenching within a square glass capillary immobilizing graphene oxide–antibody conjugate and fluorescently labelled antibody
Authors: Shirai Akihiro , Henares Terence G. , Sueyoshi Kenji , Endo Tatsuro , Hisamoto Hideaki
Published: April 2016

A single-step immunoassay device for ultrafast measurement of proteins within 40 seconds, fabricated by using a square glass capillary, antibody–graphene oxide conjugate and fluorescently labelled antibody, was developed.
Inverted organic photovoltaic cells
Authors: Wang Kai , Liu Chang , Meng Tianyu , Yi Chao , Gong Xiong
Published: April 2016

Recent progresses in device structures, working mechanisms, functions and advances of each component layer, as well their correlations with the efficiency and stability of inverted OPVs, are reviewed and illustrated.
Development of trackable metal-based drugs: new generation of therapeutic agents
Authors: Bertrand Benoît , Doulain Pierre-Emmanuel , Goze Christine , Bodio Ewen
Published: April 2016

Today, it is not sufficient to conceive an efficient drug, its mechanism of action have to be understood. To tackle this issue, trackable therapeutic agents are an interesting solution.
Influence of the pore architecture on the selective conversion of ethene to propene and butenes over medium pore zeolites
Authors: Follmann S. , Ernst S.
Published: April 2016

Conversion of ethene on selected zeolites structures allowed for high selectivities for propene and butenes.
Synthesis, photophysics, and reverse saturable absorption of 7-(benzothiazol-2-yl)-9,9-di(2-ethylhexyl)-9H-fluoren-2-yl tethered [Ir(bpy)(ppy)2]PF6and Ir(ppy)3complexes (bpy = 2,2′-bipyridine, ppy = 2-phenylpyridine)
Authors: Li Zhongjing , Li Hui , Gifford Brendan J. , Peiris Wadumesthrige D. N. , Kilina Svetlana , Sun Wenfang
Published: April 2016

Both the charges and benzothiazolylfluorenyl pendant on the 2-phenylpyridine ligand influence the photophysics and reverse saturable absorption of Ir(iii) complexes.
Cephalosporins inhibit human metallo β-lactamase fold DNA repair nucleases SNM1A and SNM1B/apollo
Authors: Lee Sook Y. , Brem Jürgen , Pettinati Ilaria , Claridge Timothy D. W. , Gileadi Opher , Schofield Christopher J. , McHugh Peter J.
Published: April 2016

The human metallo-β-lactamase fold DNA repair enzymes SNM1A and SNM1B can be inhibited by cephalosporin-family molecules, revealing a potential new strategy to chemosensitive tumours, as well as a novel evolutionary link.
The secondary coordination sphere controlled reactivity of a ferric-superoxo heme: unexpected conversion to a ferric hydroperoxo intermediate by reaction with a high-spin ferrous heme
Authors: Nagaraju Perumandla , Ohta Takehiro , Liu Jin-Gang , Ogura Takashi , Naruta Yoshinori
Published: April 2016

Incorporation of a proton mediator above the Fe porphyrin at a suitable position remarkably reduces the activation energy from the Fe-superoxide complex to the corresponding Fe-peroxide.
Palladium-catalyzed cascade cyclization of allylamine-tethered alkylidenecyclopropanes: facile access to iodine/difluoromethylene- and perfluoroalkyl-containing 1-benzazepine scaffolds
Authors: Yu Liu-Zhu , Zhu Zi-Zhong , Hu Xu-Bo , Tang Xiang-Ying , Shi Min
Published: April 2016

Palladium-catalyzed radical cascade iododifluoromethylation and iodoperfluoroalkyation/cyclization of allylamine-tethered alkylidenecyclopropanes (ACPs) were developed.
“Conformational lock” via unusual intramolecular C–F⋯OC and C–H⋯Cl–C parallel dipoles observed in in situ cryocrystallized liquids
Authors: Dey Dhananjay , Bhandary Subhrajyoti , Sirohiwal Abhishek , Hathwar Venkatesha R. , Chopra Deepak
Published: April 2016

This study highlights the unusual features associated with the arrangement of parallel bond dipoles play a role in conformational locking inin situcryocrystallized liquids.
Metal-driven assembly of peptidic foldamers: formation of molecular tapes
Authors: Solà Jordi , Bolte Michael , Alfonso Ignacio
Published: April 2016

Supramolecular structures are formed by the self-assembly of a peptidic foldamer with silver cations. The conformation of the peptide is preserved in the metal–organic fibres.
Nanoporous chalcogenides for adsorption and gas separation
Authors: Ori Guido , Massobrio Carlo , Pradel Annie , Ribes Michel , Coasne Benoit
Published: April 2016

A realistic model of porous chalcogenide is used to probe the viability of such a class of materials for adsorption and phase separation applications.
Characterization of water dissociation on α-Al2O3(11̄02): theory and experiment
Authors: Wirth Jonas , Kirsch Harald , Wlosczyk Sebastian , Tong Yujin , Saalfrank Peter , Campen R. Kramer
Published: April 2016

The interaction of small amounts of water with the alpha-alumina (11̄02) surface is explored experimentally and theoretically. We find that adsorption happens via the 1–4 channel but that dissociative and molecular states likely coexist.
BaGdF5:Dy3+,Tb3+,Eu3+ multifunctional nanospheres: paramagnetic, luminescence, energy transfer, and tunable color
Authors: Guan Hongxia , Song Yanhua , Zheng Keyan , Sheng Ye , Zou Haifeng
Published: April 2016

The photoluminescence emission color tones of BaGdF5:Dy3+,Tb3+,Eu3+ nanomaterials change from yellow-green to red by adjusting the doping concentration and the different excitation wavelengths. Furthermore, the obtained samples also exhibit paramagnetic properties.
Dietary peptides from the non-digestible fraction of Phaseolus vulgaris L. decrease angiotensin II-dependent proliferation in HCT116 human colorectal cancer cells through the blockade of the renin–angiotensin system
Authors: Luna-Vital Diego A. , Liang Katie , González de Mejía Elvira , Loarca-Piña Guadalupe
Published: April 2016

Peptides in common beans reduced angiotensin II-dependent proliferation in HCT116 colon cancer cells.
Gel integration for microfluidic applications
Authors: Zhang Xuanqi , Li Lingjun , Luo Chunxiong
Published: April 2016

We systematically review the physical properties of hydrogels, general methods for gel–microfluidics integration and applications of this field.
Protection effect of nicotinamide on cardiomyoblast hypoxia/re-oxygenation injury: study of cellular mitochondrial metabolism
Authors: Wang He , Liang Xiaoping , Luo Guoan , Ding Mingyu , Liang Qionglin
Published: April 2016

Nicotinamide exerts a protective effect on cardiomyoblasts against hypoxia/re-oxygenation-induced injury through reduction of reactive oxygen species generation via succinate dehydrogenase inhibition.
Multi-component superstructures self-assembled from nanocrystal building blocks
Authors: Tan Rui , Zhu Hua , Cao Can , Chen Ou
Published: April 2016

Synthetic strategies, superstructures, properties and applications of multi-component metamaterials self-assembled from nanocrystals have been highlighted in this minireview article.
Construction of PEG-based amphiphilic brush polymers bearing hydrophobic poly(lactic acid) side chains via successive RAFT polymerization and ROP
Authors: Qian Wenhao , Song Xuemei , Feng Chun , Xu Peicheng , Jiang Xue , Li Yongjun , Huang Xiaoyu
Published: April 2016

This article reports the synthesis of PEG-b-(PAA-g-PLA) amphiphilic brush polymers by the combination of RAFT polymerization and organocatalytic ROP, which could self-assemble into spheres for sustained release of doxorubicin.
Glyco-copolypeptide grafted magnetic nanoparticles: the interplay between particle dispersion and RNA loading
Authors: Borase T. , Fox E. K. , Haddassi Fadwa El , Cryan S.-A. , Brougham D. F. , Heise A.
Published: April 2016

Lysine-glyco-copolypeptide grafted superparamagnetic iron oxide nanoparticles were prepared through N-carboxyanhydride (NCA) copolymerization. Statistical and block copolymer arrangements were obtained while keeping the overal composition constant.
Multiple-responsive ionic complex luminogen of quinine and camphorsulfonic acid with aggregation-induced emission
Authors: Huang Pei-Yi , Gao Jhen-Yan , Song Cheng-Yu , Hong Jin-Long
Published: April 2016

Bulky camphorsulfonic acid (CSA) was used to complex with quinine (Qu) to impose restricted intramolecular rotation (RIR) required for aggregation-induced emission (AIE) properties.
Facile synthesis of ZnPc nanoflakes for cold cathode emission
Authors: Samanta Madhupriya , Ghorai Uttam Kumar , Das Biswajit , Howli Promita , Das Swati , Sen Dipayan , Chattopadhyay Kalyan Kumar
Published: April 2016

Field emission characteristics of well resolved ZnPc nanoflakes through hydrothermal method and simulation via finite element method.
Acetylacetone: a promising electrolyte solvent for dye sensitized solar cells
Authors: Gondane Vivekanand , Bhargava Parag
Published: April 2016

The electrolyte is an indispensable component of dye sensitized solar cells (DSSCs) known to exert a significant influence on the efficiency and stability of DSSCs.
Novel approach to percolation threshold on electrical conductivity of carbon nanotube reinforced nanocomposites
Authors: Sánchez-Romate Xoan F. , Jiménez-Suárez Alberto , Sánchez María , Güemes Alfredo , Ureña Alejandro
Published: April 2016

An analytical model to correlate dispersion state given by waviness, aspect ratio and agglomerate size to the electrical conductivity of CNT nanocomposites is developed.
Biocompatible polydopamine-like particles for the removal of heavy metals at extremely low concentrations
Authors: Contreras Rodríguez Ada Rebeca , Saiz-Poseu Javier , García-Pardo Javier , García Beatriz , Lorenzo Julia , Ojea-Jiménez Isaac , Komilis Dimitrios , Sedó Josep , Busqué Felix , Sánchez Antoni , Ruiz-Molina Daniel , Font Xavier
Published: April 2016

A family of catechol-based submicron particles, with sizes between 200 and 300 nm, was tested for the removal of Cd(ii), Pb(ii) and Cr(vi) in water.
Crystalline structures in tetracosane–asphaltene films
Authors: Santos Salomé dos , Poulikakos Lily D. , Partl Manfred N.
Published: April 2016

Undulated structures of tetracosane–asphaltene films and surface of bitumen are identical.
Switchable polymer reactor composed of mussel-inspired polymer that contains Au nanoparticles
Authors: Wei Wenjing , Zhu Maiyong , Shen Xiaojuan , Wu Shuping , Li Songjun
Published: April 2016

A novel polymer reactor capable of adapting to switch in aqueous media was presented. Consisting of a mussel-inspired polymer and Au nanoparticles, this polymer reactor shows a promising prospect for tunable catalysis occurring in aqueous media.
Synthesis and solution properties of novel thermo- and pH-responsive poly(N-vinylcaprolactam)-based linear–dendritic block copolymers
Authors: Tang Gang , Hu Minqi , Ma Yongcui , You Dan , Bi Yunmei
Published: April 2016

This study describes the synthesis and solution properties of the novel linear–dendritic block copolymers (LDBCs) based on thermoresponsive poly(N-vinylcaprolactam) (PNVCL) chains and pH-responsive poly(benzyl ether) dendrons.
Cl-assisted highly efficient synthesis of FePd3 alloys encapsulated in graphite papers: a two stage CVD approach
Authors: Guo Jian , Ye Qingyu , Lan Mu , Wang Shanling , Yu Tian , Gao Fuhua , Hu Dejiao , Wang Ping , He Yi , Boi Filippo S. , Zhang Sijie , Xiang Gang
Published: April 2016

We propose an advanced two-stage CVD method which allows the synthesis of very thick deposits of planar rolled-like graphite structures filled with FePd3 alloys as dominant product in the entire reactor.
A review of harvesting clean fuels from enzymatic CO2reduction
Authors: Sultana Sabiha , Chandra Sahoo Prakash , Martha Satyabadi , Parida Kulamani
Published: April 2016

This review has summarised single enzyme, multi enzymatic and semiconducting nanomaterial integrated enzymatic systems for CO2conversion to clean fuels.
A novel ion imprinted SiO2 microsphere for the specific and rapid extraction and pre-concentration of ultra-trace methyl mercury
Authors: Jiang Wenjing , Chen Zhiqiang , Cheng Xian , Wu Weihua , Wu Yongning , Xu Liangjun , Fu FengFu
Published: April 2016

A novel MeHg ion imprinted silica microsphere was designed and synthesized for the specific, cost-effective and rapid pre-concentration of ultra-trace MeHg from natural water.
Advanced generation of paeonol-phenylsufonyl derivatives as potential anti-HBV agents
Authors: Huang Y. P. , Shih H. P. , Liang Y. C. , Lin H. H. , Lin M. C. , Chen C. W. , Huang T. J. , Kuo Y. C. , Han C. C. , Hsu M. H.
Published: April 2016

Among all the compounds we presented here, 8a showed the most potent inhibitory effect and highest selectivity index, which exceeds those of lamivudine (3TC) and our previously synthesized compound 6f.
Enhanced performance of a Pt-based three-way catalyst using a double-solvent method
Authors: Chen Jianjun , Huang Fujin , Hu Wei , Li Guangxia , Zhong Lin , Chen Yaoqiang
Published: April 2016

A new Pt-based three-way catalyst (TWC) for compressed natural gas (CNG) exhausts emissions was developed using a double-solvent method.
Pillar[10]arene-based host–guest complexation promoted self-assembly: from nanoparticles to uniform giant vesicles
Authors: Yang Jie , Li Zhengtao , Shao Li , Yu Guocan
Published: April 2016

A novel host-guest recognition motif between a water-soluble pillar[10]arene and pyrene derivative was established and further applied in the fabrication of a pH-responsive supra-amphiphile.
Nitrogen-doped heterostructure carbon functionalized by electroactive organic molecules for asymmetric supercapacitors with high energy density
Authors: Guo Bingshu , Hu Zhongai , An Yufeng , An Ning , Jia Pengfei , Zhang Yadi , Yang Yuying , Li Zhimin
Published: April 2016

The organic molecules (TCBQ, AQ) with multi-electron redox center are selected to modify nitrogen-doped heterostructure carbon (NHC) by noncovalent interaction and the electrode materials show good performances and potential self-matching behaviors.
Correction: Calcite precipitation from by-product red gypsum in aqueous carbonation process
Authors: Rahmani Omeid , Tyrer Mark , Junin Radzuan
Published: April 2016

Correction for ‘Calcite precipitation from by-product red gypsum in aqueous carbonation process’ by Omeid Rahmani et al., RSC Adv., 2014, 4, 45548–45557.
Superior upconversion fluorescence dopants for highly efficient deep-blue electroluminescent devices
Authors: Chen Yi-Hsiang , Lin Chih-Chun , Huang Min-Jie , Hung Kevin , Wu Yi-Ching , Lin Wei-Chieh , Chen-Cheng Ren-Wu , Lin Hao-Wu , Cheng Chien-Hong
Published: April 2016

Highly efficient deep-blue electroluminescent devices are realized via an efficient triplet–triplet annihilation process of styrylpyrene-based emitters.
Direct alkylation of heteroarenes with unactivated bromoalkanes using photoredox gold catalysis
Authors: McCallum T. , Barriault L.
Published: April 2016

A protocol for direct C–H alkylation of heteroarenes was developed using photoredox catalysis as a mode of activation for unactivated bromoalkanes. Dimeric Au(i) complex, [Au2(dppm)2]Cl2, served as an efficient photocatalyst for this transformation.
Multiple welding of long fiber epoxy vitrimer composites
Authors: Chabert Erwan , Vial Jérôme , Cauchois Jean-Pierre , Mihaluta Marius , Tournilhac François
Published: April 2016

Epoxy vitrimer composites show the ability to be repeatedly welded thanks to improved surface conformity and chemical bonding through exchange reactions.
Polybenzoxazine-based highly porous carbon nanofibrous membranes hybridized by tin oxide nanoclusters: durable mechanical elasticity and capacitive performance
Authors: Ge Jianlong , Qu Yongshuai , Cao Leitao , Wang Fei , Dou Lvye , Yu Jianyong , Ding Bin
Published: April 2016

Polybenzoxazine-based highly porous carbon nanofibrous membranes hybridized by tin oxide nanoclusters with durable mechanical elasticity and stable capacitive performance.
Preparation of graphene nano-sheet bonded PDA/MOF microcapsules with immobilized glucose oxidase as a mimetic multi-enzyme system for electrochemical sensing of glucose
Authors: Wang Yang , Hou Chen , Zhang Yun , He Fu , Liu Mingzhu , Li Xiaoli
Published: April 2016

A novel amperometric biosensor for glucose detection was fabricated based on a mimetic multi-enzyme system by combing mimetic enzymes (metal–organic frameworks, MOFs) and glucose oxidase (GOx).
Metallothioneins act downstream of insulin signaling to regulate toxicity of outdoor fine particulate matter (PM2.5) during Spring Festival in Beijing in nematode Caenorhabditis elegans
Authors: Yang Ruilong , Rui Qi , Kong Ling , Zhang Nan , Li Yu , Wang Xinyu , Tao Jing , Tian Peiyao , Ma Yan , Wei Jianrong , Li Guojun , Wang Dayong
Published: April 2016

mtl-1andmtl-2encoded metallothioneins act downstream of insulin signaling to regulate toxicity of outdoor PM2.5during Spring Festival in Beijing.
Robust power control for femtocell networks with imperfect channel state information
Authors: Liu Zhixin , Zhang Peng , Guan Xinping , Li Xinbin , Yang Hongjiu
Published: April 2016

In this study, the authors study the power control for a two‐tier network system which is comprised of a central macrocell and several femtocells. In practice, the communication environment is fairly complex and dynamic which leads to the imperfect channel state information (CSI). To enhance the robustness of the two‐tier network system, the imperfect CSI in both signal links and interference links are considered and the uncertainties of the CSI are uniformly distributed in an ellipsoid uncertainty set. Then, a probability‐constrained optimisation problem is formulated to deal with the uncertainties and protect the quality‐of‐service of all users. A novel method is provided to convert probability constraints into deterministic ones. Based on them, they propose an iterative algorithm and an admission control algorithm to enhance the network efficiency. They also investigate the case when the distributions of the uncertainties of the CSI are unknown. Finally, numerical results are given to illustrate the effectiveness of the authors’ power control scheme.
Scalable subband subsampled radio architecture for millimetre wave communications with performance analysis
Authors: Rakesh R.T. , Kutty Shajahan , Sen Debarati , Das Goutam
Published: April 2016

Millimetre wave bands are envisaged to be utilised for next generation ultra‐high data rate communications due to the availability of large bandwidths. However, high sampling rate requirement at these frequencies leads to significant power consumption in the devices. In this study, a subband‐based subsampled radio architecture is proposed for indoor millimetre wave communications with the objective of improving power efficiency along with scalable data rates and multi‐user support under varying Quality of Service (QoS) requirements. An optimum bandwidth partitioning scheme is presented to support the proposed architecture. Subbanding in association with orthogonal spreading codes enables the reduction of sampling rate requirement at the receiver, resulting in significant power savings for medium data rate communication systems. Furthermore, the performance evaluation of the scheme is performed by deriving closed‐form analytical expressions for probability of bit error under line‐of‐sight (LOS) and non‐LOS conditions considering the effect of antenna half‐power beamwidth. The analytical expressions and simulation results for different requirements including maximum data rate, variable number of users, and variable QoS are evaluated and compared.
Modelling, analysis and performance comparison of two direct sampling DCSK receivers under frequency non‐selective fading channels
Authors: Quyen Nguyen Xuan , Duong Trung Q. , Nallanathan Arumugam
Published: April 2016

Two direct sampling correlator‐type receivers for differential chaos shift keying (DCSK) communication systems under frequency non‐selective fading channels are proposed. These receivers operate based on the same hardware platform with different architectures. In the first scheme, namely sum‐delay‐sum (SDS) receiver, the sum of all samples in a chip period is correlated with its delayed version. The correlation value obtained in each bit period is then compared with a fixed threshold to decide the binary value of recovered bit at the output. On the other hand, the second scheme, namely delay‐sum‐sum (DSS) receiver, calculates the correlation value of all samples with its delayed version in a chip period. The sum of correlation values in each bit period is then compared with the threshold to recover the data. The conventional DCSK transmitter, frequency non‐selective Rayleigh fading channel, and two proposed receivers are mathematically modelled in discrete‐time domain. The authors evaluated the bit error rate performance of the receivers by means of both theoretical analysis and numerical simulation. The performance comparison shows that the two proposed receivers can perform well under the studied channel, where the performances get better when the number of paths increases and the DSS receiver outperforms the SDS one.
Throughput maximisation by optimising detection thresholds in full‐duplex cognitive radio networks
Authors: Tuan Pham Viet , Koo Insoo
Published: April 2016

Herein the authors consider throughput maximisation for a secondary user (SU) in a full‐duplex cognitive radio network (FD‐CRN) when the SU has two separate antennas and a self‐interference suppression capability. In the FD‐CRN, the SU can simultaneously sense the spectrum throughout the whole time slot and transmit data. They propose algorithms based on brute‐force search and particle swarm optimisation methods to help the SU achieve optimal detection thresholds for spectrum sensing in two different FD‐CRN scenarios. In the first scenario, the SU individually performs spectrum sensing, whereas in the second scenario the SU's sensing results are improved by means of cooperative spectrum sensing. Theoretical and simulation results herein show that, for certain values of the system parameters in the above two scenarios, the system under consideration provides much higher throughput than previously proposed systems in conditions of high‐transmission power or low signal‐to‐noise ratio of the primary signal.
Automated cyclist data collection under high density conditions
Authors: Zaki Mohamed H. , Sayed Tarek
Published: April 2016

This paper demonstrates the effectiveness of video analysis for a cyclist’s data collection in high‐density environments. It attempts to address the shortcomings of conventional data collection methods by conducting an automated study to obtain real‐world bicycle data and providing a validation scheme to assess the accuracy of the automated observations. Basic traffic quantities such as average speed, volume count, flow rate, and density are automatically estimated and validated. Furthermore, traffic analysis applications are conducted on the collected data as a demonstration of the capabilities of the automated computer vision system. The analysis is applied to a data set collected through video cameras at a cycling event at the University of British Columbia. The analysis indicates the feasibility to automate the cyclist traffic data collection process in challenging, dense conditions. The reported results can provide a motivation for traffic engineers to rely on automated data collection as guidance during the decision‐making process and to explore further the relationship between the bike facilities width, the expected flows, the facilities performance, and level of safety.
Testing energy and emissions assessment models: a highway case study in virtual reality
Authors: Cristiano Silvio
Published: April 2016

The estimation of pollutants from road transport systems is examined, by comparing emission factors (EFs) calculated with static and dynamic methods. Information technology is used to test currently operational assessment models in the European Union. The negligibility of the effects of variation in speed is questioned: acceleration/deceleration imply use/dissipation of energy, and directly affect pollutants release. An investigation based on drive simulation is conducted, proposing increasing traffic flow conditions. Two scenarios are simulated: an existing highway before and after major modernisation works. Benefits and detriments of its renovation are also examined. Results are processed through recent European Environment Agency models and a system that continuously computes the operations of an engine. The correlation found between average speed and EFs is not representative. Instead, a good correlation is observed between increases in speed variation and increases of EFs. Synthetic parameters are proposed to support the analysis, based on intensity and duration of acceleration/deceleration events. EFs are substantially lower if calculated through the static models. The assumption that the effects of speed variation can be neglected is rejected: driving cycles due to traffic flow conditions are identified as crucial for realistically evaluating emissions. A need is detected to formulate correcting parameters.
Investigation of the trade‐off between switching losses and EMI generation in Gaussian S‐shaping for high‐power IGBT switching transients by active voltage control
Authors: Yang Xin , Long Zhiqiang , Wen Yanhui , Huang Haokai , Palmer Patrick R.
Published: April 2016

Over three decades of development effort has brought insulated gate bipolar transistor (IGBT) technology to a high‐level of maturity. IGBT converters have been widely used in industry. However, the high‐speed switching transient of the IGBT‐freewheel diode chopper cell causes high‐level electromagnetic interference (EMI). Electromagnetic compatibility requirements are normally taken into account by utilising costly EMI filters or shielding on the load and supply side. The risk of this traditional method is to incur a delay in commercialising the converters since identification of the failure causes, modifications, and successfully re‐testing are required. A promising alternative is to constrain the EMI at source by introducing active voltage control technique and shaping the IGBT switching transient into a sophisticated ‘S’‐shape. Previously, IGBT switching waveforms have been successfully shaped into an advanced Gaussian ‘S’‐shape with the EMI greatly reduced. In this study, the authors further investigated the trade‐off between EMI generation and switching losses in such an S‐shaping method. The investigation was carried out in an accurate physical IGBT/diode model that is able to accurately simulate the device switching transient. From the results, it can be seen that by using the Gaussian S‐shaping method the trade‐off between EMI and switching losses could be much improved.
Challenges in the adoption of hybrid cloud: an exploratory study using systematic literature review
Authors: Khan Siffat Ullah , Ullah Naeem
Published: April 2016

Cloud computing is a growing computing paradigm that provides Internet‐based computer services on‐demand basis. Adoption of cloud infrastructure promises enterprises numerous benefits. In particular, hybrid cloud, a combination of both public and private clouds, offers benefits of both the public and private clouds. The objective of this study is to identify the critical challenges, faced by client organisations in the adoption of hybrid cloud computing. The authors have reviewed the literature through systematic literature review (SLR) process. We have followed all the SLR steps by developing SLR protocol first which was then validated and implemented. We have identified a list of ten challenges, by extracting data from a sample of 120 papers, in the adoption of hybrid cloud. The identified challenges include three critical challenges such as: ‘public cloud security concern’, ‘efficient management issue’, and ‘integration complexity’. We have further analysed the identified challenges with respect to time and study strategy. Clients should address all the identified challenges in general and the critical challenges in particular. Our next phase of the study is validation of the identified challenges through industry practitioners and to find solutions/practices for addressing these challenges, which will be published in future.
Ultrafast proton radiography of the magnetic fields generated by a laser-driven coil current
Authors: Gao Lan , Ji Hantao , Fiksel Gennady , Fox William , Evans Michelle , Alfonso Noel
Published: April 2016

Magnetic fields generated by a current flowing through a U-shaped coil connecting two copper foils were measured using ultrafast proton radiography. Two ∼1.25 kJ, 1-ns laser pulses propagated through laser entrance holes in the front foil and were focused to the back foil with an intensity of ∼3 × 1016 W/cm2. The intense laser-solid interaction induced a high voltage between the copper foils and generated a large current in the connecting coil. The proton data show ∼40–50 T magnetic fields at the center of the coil ∼3–4 ns after laser irradiation. The experiments provide significant insight for future target designs that aim to develop a powerful source of external magnetic fields for various applications in high-energy-density science.
Predissociation dynamics in the 3pπD1Πu±υ=3 and 4pσB″1Σu+υ=1 states of H2 revealed by product branching ratios and fragment angular distributions
Authors: Meng Qingnan , Mo Yuxiang
Published: April 2016

The predissociation dynamics of H2+XUV→H2*→H(1s)+H(2s,2p) has been studied by measuring the fragment branching ratios between the H(2s) and H(2p) states and the fragment angular distributions using the XUV (extreme ultraviolet) laser pump and UV (ultraviolet) laser probe method. The fragment angular distributions for the predissociation of the 3pπD1Πu+υ=3 state show parallel transitions, demonstrating that the main components of the dissociating state have 1Σu+ symmetry. The measured fragment branching ratios, H(2s)/(H(2s) + H(2p)), for the transitions R(0), R(1), and P(2) in 3pπD1Πu+υ=3←X1Σg+υ″=0 are in good agreement with one of the previous theoretical predictions. The predissociations of the 3pπD1Πu−(υ=3) state arising from the Q(1), Q(2), and Q(3) lines have also been observed. The angular distributions and the state distributions of the excited fragments (all found from the H(2p) state) illustrate that the dissociating states for the Q lines have the expected Πu− symmetry. The predissociation dynamics of the transition 4pσB″1Σu+υ=1←X1Σg+υ″=0 was also studied. Their fragment angular distributions show the expected parallel transitions, and most of the fragments are in the H(2s) states. The Beutler-Fano profiles and the associated spectroscopic parameters for the predissociations have also been obtained by measuring the fragment yield of H(2s, 2p) as a function of excitation photon energies.
On the inclusion of the diagonal Born-Oppenheimer correction in surface hopping methods
Authors: Gherib Rami , Ye Liyuan , Ryabinkin Ilya G. , Izmaylov Artur F.
Published: April 2016

The diagonal Born-Oppenheimer correction (DBOC) stems from the diagonal second derivative coupling term in the adiabatic representation, and it can have an arbitrary large magnitude when a gap between neighbouring Born-Oppenheimer (BO) potential energy surfaces (PESs) is closing. Nevertheless, DBOC is typically neglected in mixed quantum-classical methods of simulating nonadiabatic dynamics (e.g., fewest-switch surface hopping (FSSH) method). A straightforward addition of DBOC to BO PESs in the FSSH method, FSSH+D, has been shown to lead to numerically much inferior results for models containing conical intersections. More sophisticated variation of the DBOC inclusion, phase-space surface-hopping (PSSH) was more successful than FSSH+D but on model problems without conical intersections. This work comprehensively assesses the role of DBOC in nonadiabatic dynamics of two electronic state problems and the performance of FSSH, FSSH+D, and PSSH methods in variety of one- and two-dimensional models. Our results show that the inclusion of DBOC can enhance the accuracy of surface hopping simulations when two conditions are simultaneously satisfied: (1) nuclei have kinetic energy lower than DBOC and (2) PESs are not strongly nonadiabatically coupled. The inclusion of DBOC is detrimental in situations where its energy scale becomes very high or even diverges, because in these regions PESs are also very strongly coupled. In this case, the true quantum formalism heavily relies on an interplay between diagonal and off-diagonal nonadiabatic couplings while surface hopping approaches treat diagonal terms as PESs and off-diagonal ones stochastically.
Structural properties of Cu2O epitaxial films grown on c-axis single crystal ZnO by magnetron sputtering
Authors: Gan J. , Gorantla S. , Riise H. N. , Fjellvåg Ø. S. , Diplas S. , Løvvik O. M. , Svensson B. G. , Monakhov E. V. , Gunnæs A. E.
Published: April 2016

Epitaxial Cu2O films grown by reactive and ceramic radio frequency magnetron sputtering on single crystalline ZnO (0001) substrates are investigated. The films are grown on both O- and Zn-polar surface of the ZnO substrates. The Cu2O films exhibit a columnar growth manner apart from a ∼5 nm thick CuO interfacial layer. In comparison to the reactively sputtered Cu2O, the ceramic-sputtered films are less strained and appear to contain nanovoids. Irrespective of polarity, the Cu2O grown by reactive sputtering is observed to have (111)Cu2O||(0001)ZnO epitaxial relationship, but in the case of ceramic sputtering the films are found to show additional (110)Cu2O reflections when grown on O-polar surface. The observed CuO interfacial layer can be detrimental for the performance of Cu2O/ZnO heterojunction solar cells reported in the literature.
Nonequilibrium solvent effects in Born-Oppenheimer molecular dynamics for ground and excited electronic states
Authors: Bjorgaard J. A. , Velizhanin K. A. , Tretiak S.
Published: April 2016

The effects of solvent on molecular processes such as excited state relaxation and photochemical reaction often occurs in a nonequilibrium regime. Dynamic processes such as these can be simulated using excited state molecular dynamics. In this work, we describe methods of simulating nonequilibrium solvent effects in excited state molecular dynamics using linear-response time-dependent density functional theory and apparent surface charge methods. These developments include a propagation method for solvent degrees of freedom and analytical energy gradients for the calculation of forces. Molecular dynamics of acetaldehyde in water or acetonitrile are demonstrated where the solute-solvent system is out of equilibrium due to photoexcitation and emission.
Fast equilibration protocol for million atom systems of highly entangled linear polyethylene chains
Authors: Sliozberg Yelena R. , Kröger Martin , Chantawansri Tanya L.
Published: April 2016

Equilibrated systems of entangled polymer melts cannot be produced using direct brute force equilibration due to the slow reptation dynamics exhibited by high molecular weight chains. Instead, these dense systems are produced using computational techniques such as Monte Carlo-Molecular Dynamics hybrid algorithms, though the use of soft potentials has also shown promise mainly for coarse-grained polymeric systems. Through the use of soft-potentials, the melt can be equilibrated via molecular dynamics at intermediate and long length scales prior to switching to a Lennard-Jones potential. We will outline two different equilibration protocols, which use various degrees of information to produce the starting configurations. In one protocol, we use only the equilibrium bond angle, bond length, and target density during the construction of the simulation cell, where the information is obtained from available experimental data and extracted from the force field without performing any prior simulation. In the second protocol, we moreover utilize the equilibrium radial distribution function and dihedral angle distribution. This information can be obtained from experimental data or from a simulation of short unentangled chains. Both methods can be used to prepare equilibrated and highly entangled systems, but the second protocol is much more computationally efficient. These systems can be strictly monodisperse or optionally polydisperse depending on the starting chain distribution. Our protocols, which utilize a soft-core harmonic potential, will be applied for the first time to equilibrate a million particle system of polyethylene chains consisting of 1000 united atoms at various temperatures. Calculations of structural and entanglement properties demonstrate that this method can be used as an alternative towards the generation of entangled equilibrium structures.
Negative to positive crossover of the magnetoresistance in layered WS2
Authors: Zhang Yangwei , Ning Honglie , Li Yanan , Liu Yanzhao , Wang Jian
Published: April 2016

The discovery of graphene ignited intensive investigation of two-dimensional materials. A typical two-dimensional material, transition metal dichalcogenide (TMDC), attracts much attention because of its excellent performance in field effect transistor measurements and applications. Particularly, when TMDC reaches the dimension of a few layers, a wide range of electronic and optical properties can be detected that are in striking contrast to bulk samples. In this letter, we synthesized WS2 single-crystal nanoflakes using physical vapor deposition and carried out a series of measurements of the contact resistance and magnetoresistance. Focused ion beam (FIB) technology was applied to deposit Pt electrodes on the WS2 flakes, and the FIB-deposited contacts exhibited linear electrical characteristics. Resistance versus temperature measurements showed similar Mott variable range hopping behavior in different magnetic fields. Additionally, a temperature-modulated negative-to-positive magnetoresistance transition was observed. Our work reveals the magnetotransport characteristics of WS2 flakes, which may stimulate further studies of the properties of TMDC and its corresponding electronic and optoelectronic applications.
Analysis of the tuning characteristics of microwave plasma source
Authors: Miotk Robert , Jasiński Mariusz , Mizeraczyk Jerzy
Published: April 2016

In this paper, we present an analysis of the tuning characteristics of waveguide-supplied metal-cylinder-based nozzleless microwave plasma source. This analysis has enabled to estimate the electron concentration ne and electron frequency collisions ν in the plasma generated in nitrogen and in a mixture of nitrogen and ethanol vapour. The parameters ne and ν are the basic quantities that characterize the plasma. The presented new plasma diagnostic method is particularly useful, when spectroscopic methods are useless. The presented plasma source is currently used in research of a hydrogen production from liquids.
The investigation of the wetting behavior on the red rose petal
Authors: Jin Haiyun , Li Yufeng , Zhang Peng , Nie Shichao , Gao Naikui
Published: April 2016

The study on superhydrophobicity is based on the wetting behavior of droplets on the rough surface. The wetting behavior on the red rose petal was observed by optical microscope at micrometer scale. Results showed that the wetting behavior was dynamic and air moved slowly between the droplet and the red rose petal. Many isolated air cushions were also found at the interface. In order to explain the relationship between the wetting behavior and the high adhesive force on the rose petal, a geometric model about solid-liquid-air three phase interface was proposed. The adhesion on the rose petal mainly depended on the sealed air inside the interface which could not connect to the atmosphere and the strong association of the solid/liquid at Wenzel wetting domains in this model.
Exceptionally crystalline and conducting acid doped polyaniline films by level surface assisted solution casting approach
Authors: B. Puthirath Anand , Methattel Raman Shijeesh , Varma Sreekanth J. , S Jayalekshmi
Published: April 2016

Emeraldine salt form of polyaniline (PANI) was synthesized by chemical oxidative polymerisation method using ammonium persulfate as oxidant. Resultant emeraldine salt form of PANI was dedoped using ammonia solution and then re-doped with camphor sulphonic acid (CSA), naphthaline sulphonic acid (NSA), hydrochloric acid (HCl), and m-cresol. Thin films of these doped PANI samples were deposited on glass substrates using solution casting method with m-cresol as solvent. A level surface was employed to get homogeneous thin films of uniform thickness. Detailed X-ray diffraction studies have shown that the films are exceptionally crystalline. The crystalline peaks observed in the XRD spectra can be indexed to simple monoclinic structure. FTIR and Raman spectroscopy studies provide convincing explanation for the exceptional crystallinity observed in these polymer films. FESEM and AFM images give better details of surface morphology of doped PANI films. The DC electrical conductivity of the samples was measured using four point probe technique. It is seen that the samples also exhibit quite high DC electrical conductivity, about 287 S/cm for CSA doped PANI, 67 S/cm for NSA doped PANI 65 S/cm for HCl doped PANI, and just below 1 S/cm for m-cresol doped PANI. Effect of using the level surface for solution casting is studied and correlated with the observed crystallinity.
The transition from stress softening to stress hardening under cyclic loading induced by magnetic field for magneto-sensitive polymer gels
Authors: Xu Yangguang , Liao Guojiang , Zhang Canyang , Wan Qiang , Liu Taixiang
Published: April 2016

Magneto-sensitive polymer gel (MSPG) is a kind of ferromagnetic particle filled smart polymer composite, whose magneto-mechanical coupling mechanism has attracted increasing attention in recent years. In this work, the magneto-induced rheological response of MSPG under cyclic shear loading was investigated. It was found that magnetic field is the critical reason for the transition from stress softening to stress hardening under cyclic loading. Besides, the particle concentration and temperature are the controlling factors in the structure optimization of MSPG in the presence of magnetic field. The magneto-induced hardening mechanism was further proposed based on the related experimental results.
High-current operation of vertical-type organic transistor with preferentially oriented molecular film
Authors: Fukagawa Hirohiko , Watanabe Yasuyuki , Kudo Kazuhiro , Nishida Jun-ichi , Yamashita Yoshiro , Fujikake Hideo , Tokito Shizuo , Yamamoto Toshihiro
Published: April 2016

A high-performance vertical-type organic transistor has been fabricated using bis(l,2,5-thiadiazolo)-p-quinobis(l,3-dithiole) (BTQBT) for the channel layer. The BTQBT molecules are oriented horizontally, with the molecular plane of each monolayer parallel to the substrate. The π–π stacking direction of the BTQBT molecules is aligned with the carrier transport direction in this vertical transistor. The modulated drain current density exceeded 1 A cm−2 upon the application of a gate voltage of less than 5 V. In addition, the device exhibits a high on/off current ratio of over 105.
Phase transition temperatures of 405-725 K in superfluid ultra-dense hydrogen clusters on metal surfaces
Authors: Holmlid Leif , Kotzias Bernhard
Published: April 2016

Ultra-dense hydrogen H(0) with its typical H-H bond distance of 2.3 pm is superfluid at room temperature as expected for quantum fluids. It also shows a Meissner effect at room temperature, which indicates that a transition point to a non-superfluid state should exist above room temperature. This transition point is given by a disappearance of the superfluid long-chain clusters H2N(0). This transition point is now measured for several metal carrier surfaces at 405 - 725 K, using both ultra-dense protium p(0) and deuterium D(0). Clusters of ordinary Rydberg matter H(l) as well as small symmetric clusters H4(0) and H3(0) (which do not give a superfluid or superconductive phase) all still exist on the surface at high temperature. This shows directly that desorption or diffusion processes do not remove the long superfluid H2N(0) clusters. The two ultra-dense forms p(0) and D(0) have different transition temperatures under otherwise identical conditions. The transition point for p(0) is higher in temperature, which is unexpected.
Improved performance of GaN based light emitting diodes with ex-situ sputtered AlN nucleation layers
Authors: Chen Shuo-Wei , Li Heng , Lu Tien-Chang
Published: April 2016

The crystal quality, electrical and optical properties of GaN based light emitting diodes (LEDs) with ex-situ sputtered physical vapor deposition (PVD) aluminum nitride (AlN) nucleation layers were investigated. It was found that the crystal quality in terms of defect density and x-ray diffraction linewidth was greatly improved in comparison to LEDs with in-situ low temperature GaN nucleation layer. The light output power was 3.7% increased and the reverse bias voltage of leakage current was twice on LEDs with ex-situ PVD AlN nucleation layers. However, larger compressive strain was discovered in LEDs with ex-situ PVD AlN nucleation layers. The study shows the potential and constrain in applying ex-situ PVD AlN nucleation layers to fabricate high quality GaN crystals in various optoelectronics.
Adaptive generalized combination complex synchronization of uncertain real and complex nonlinear systems
Authors: Wang Shi-bing , Wang Xing-yuan , Wang Xiu-you , Zhou Yu-fei
Published: April 2016

With comprehensive consideration of generalized synchronization, combination synchronization and adaptive control, this paper investigates a novel adaptive generalized combination complex synchronization (AGCCS) scheme for different real and complex nonlinear systems with unknown parameters. On the basis of Lyapunov stability theory and adaptive control, an AGCCS controller and parameter update laws are derived to achieve synchronization and parameter identification of two real drive systems and a complex response system, as well as two complex drive systems and a real response system. Two simulation examples, namely, ACGCS for chaotic real Lorenz and Chen systems driving a hyperchaotic complex Lü system, and hyperchaotic complex Lorenz and Chen systems driving a real chaotic Lü system, are presented to verify the feasibility and effectiveness of the proposed scheme.