bluuebunny/crossref_metadata_2025 huggingface dataset:
Breaking the scaling relationship via thermally stable Pt/Cu single atom alloys for catalytic dehydrogenation
Authors: Sun Guodong , Zhao Zhi-Jian , Mu Rentao , Zha Shenjun , Li Lulu , Chen Sai , Zang Ketao , Luo Jun , Li Zhenglong , Purdy Stephen C. , Kropf A. Jeremy , Miller Jeffrey T. , Zeng Liang , Gong Jinlong
Published: October 2018

Noble-metal alloys are widely used as heterogeneous catalysts. However, due to the existence of scaling properties of adsorption energies on transition metal surfaces, the enhancement of catalytic activity is frequently accompanied by side reactions leading to a reduction in selectivity for the target product. Herein, we describe an approach to breaking the scaling relationship for propane dehydrogenation, an industrially important reaction, by assembling single atom alloys (SAAs), to achieve simultaneous enhancement of propylene selectivity and propane conversion. We synthesize γ-alumina-supported platinum/copper SAA catalysts by incipient wetness co-impregnation method with a high copper to platinum ratio. Single platinum atoms dispersed on copper nanoparticles dramatically enhance the desorption of surface-bounded propylene and prohibit its further dehydrogenation, resulting in high propylene selectivity (~90%). Unlike previous reported SAA applications at low temperatures (<400 °C), Pt/Cu SAA shows excellent stability of more than 120 h of operation under atmospheric pressure at 520 °C.
Author Correction: 4-dimensional functional profiling in the convulsant-treated larval zebrafish brain
Authors: Winter Matthew J. , Windell Dylan , Metz Jeremy , Matthews Peter , Pinion Joe , Brown Jonathan T. , Hetheridge Malcolm J. , Ball Jonathan S. , Owen Stewart F. , Redfern Will S. , Moger Julian , Randall Andrew D. , Tyler Charles R.
Published: October 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Integrated evidence reveals a new species in the ancient blue coral genus Heliopora (Octocorallia)
Authors: Richards Zoe T. , Yasuda Nina , Kikuchi Taisei , Foster Taryn , Mitsuyuki Chika , Stat Michael , Suyama Yoshihisa , Wilson Nerida G.
Published: October 2018

Maintaining the accretion potential and three dimensional structure of coral reefs is a priority but reef-building scleractinian corals are highly threatened and retreating. Hence future reefs are predicted to be dominated by non-constructional taxa. Since the Late Triassic however, other non-scleractinian anthozoans such as Heliopora have contributed to tropical and subtropical reef-building. Heliopora is an ancient and highly conserved reef building octocoral genus within the monospecific Family Helioporidae, represented by a single extant species – H. coerulea, Pallas, 1766. Here we show integrated morphological, genomic and reproductive evidence to substantiate the existence of a second species within the genus Heliopora. Importantly, some individuals of the new species herein described as Heliopora hiberniana sp. nov. feature a white skeleton indicating that the most diagnostic and conserved Heliopora character (the blue skeleton) can be displaced. The new species is currently known only from offshore areas in north Western Australia, which is a part of the world where coral bleaching events have severely impacted the scleractinian community over the last two decades. Field observations indicate individuals of both H. coerulea and H. hiberniana sp. nov. were intact after the 2016 Scott Reef thermal stress event, and we discuss the possibility that bleaching resistant non-scleractinian reef builders such as Heliopora could provide new ecological opportunities for the reconfiguration of future reefs by filling empty niches and functional roles left open by the regression of scleractinian corals.
Author Correction: Snake Venom Extracellular vesicles (SVEVs) reveal wide molecular and functional proteome diversity
Authors: Carregari Victor Corassolla , Rosa-Fernandes Livia , Baldasso Paulo , Bydlowski Sergio Paulo , Marangoni Sergio , Larsen Martin R. , Palmisano Giuseppe
Published: October 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Author Correction: Live Intracellular Biorthogonal Imaging by Surface Enhanced Raman Spectroscopy using Alkyne-Silver Nanoparticles Clusters
Authors: Ardini Matteo , Huang Jian-An , Sánchez Carlos S. , Mousavi Mansoureh Z. , Caprettini Valeria , Maccaferri Nicolò , Melle Giovanni , Bruno Giulia , Pasquale Lea , Garoli Denis , De Angelis Francesco
Published: October 2018

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.
Investigating the Ca2+-dependent and Ca2+-independent mechanisms for mammalian cone light adaptation
Authors: Vinberg Frans , Kefalov Vladimir J.
Published: October 2018

Vision is mediated by two types of photoreceptors: rods, enabling vision in dim light; and cones, which function in bright light. Despite many similarities in the components of their respective phototransduction cascades, rods and cones have distinct sensitivity, response kinetics, and adaptation capacity. Cones are less sensitive and have faster responses than rods. In addition, cones can function over a wide range of light conditions whereas rods saturate in moderately bright light. Calcium plays an important role in regulating phototransduction and light adaptation of rods and cones. Notably, the two dominant Ca2+-feedbacks in rods and cones are driven by the identical calcium-binding proteins: guanylyl cyclase activating proteins 1 and 2 (GCAPs), which upregulate the production of cGMP; and recoverin, which regulates the inactivation of visual pigment. Thus, the mechanisms producing the difference in adaptation capacity between rods and cones have remained poorly understood. Using GCAPs/recoverin-deficient mice, we show that mammalian cones possess another Ca2+-dependent mechanism promoting light adaptation. Surprisingly, we also find that, unlike in mouse rods, a unique Ca2+-independent mechanism contributes to cone light adaptation. Our findings point to two novel adaptation mechanisms in mouse cones that likely contribute to the great adaptation capacity of cones over rods.
Mapping anaerobic sludge bed community adaptations to manure supernatant in biogas reactors
Authors: Nordgård Anna Synnøve Røstad , Bergland Wenche Hennie , Bakke Rune , Østgaard Kjetill , Bakke Ingrid
Published: October 2018

In upflow anaerobic sludge bed (UASB) reactors, biomass present as granules allows for long solids retention time. Here, granules from a process treating pulp and paper industrial wastewater were successfully applied as inoculum in UASB reactors treating pig manure supernatant, despite high particle content and high ammonium concentrations in the influent. We did a detailed characterization of archaeal and bacterial communities associated with the inoculum and with the aggregated and dispersed fractions of the influent and the reactors after one year of operation. The granular communities underwent major changes and adapted to the highly distinct conditions without disintegration of the granules. Although the granules persisted in the reactors, non-granular aggregates accumulated, and partly replaced the granules. Particles introduced to the reactors by the pig manure influent apparently contributed both as food and biofilm growth support. Archaeal communities in the dispersed reactor phase were similar to those dispersed in the influents, implying successful retention and little loss of archaeal biomass due to detachment or disintegration of granules and other aggregates. Unique bacterial communities developed in the dispersed fraction of the reactors despite of low hydraulic retention times. They probably consisted of fast growing organisms consuming readily degradable organic matter.
Delay in the dispersal of flocks moving in unbounded space using long-range interactions
Authors: Zumaya Martín , Larralde Hernán , Aldana Maximino
Published: October 2018

Since the pioneering work by Vicsek and his collaborators on the motion of self-propelled particles, most of the subsequent studies have focused on the onset of ordered states through a phase transition driven by particle density and noise. Usually, the particles in these systems are placed within periodic boundary conditions and interact via short-range velocity alignment forces. However, when the periodic boundaries are eliminated, letting the particles move in open space, the system is not able to organize into a coherently moving group since even small amounts of noise cause the flock to break apart. While the phase transition has been thoroughly studied, the conditions to keep the flock cohesive in open space are still poorly understood. Here we extend the Vicsek model of collective motion by introducing long-range alignment interactions between the particles. We show that just a small number of these interactions is enough for the system to build up long lasting ordered states of collective motion in open space and in the presence of noise. This finding was verified for other models in addition to the Vicsek one, suggesting its generality and revealing the importance that long-range interactions can have for the cohesion of the flock.
Uric acid enhances alteplase-mediated thrombolysis as an antioxidant
Authors: Kikuchi Kiyoshi , Setoyama Kentaro , Tanaka Eiichiro , Otsuka Shotaro , Terashi Takuto , Nakanishi Kazuki , Takada Seiya , Sakakima Harutoshi , Ampawong Sumate , Kawahara Ko-ichi , Nagasato Tomoka , Hosokawa Kazuya , Harada Yoichiro , Yamamoto Mika , Kamikokuryo Chinatsu , Kiyama Ryoji , Morioka Motohiro , Ito Takashi , Maruyama Ikuro , Tancharoen Salunya
Published: October 2018

Uric acid (UA) therapy may prevent early ischemic worsening after acute stroke in thrombolysis patients. The aim of this study was to examine the influence of UA on the thrombolytic efficacy of alteplase in human blood samples by measuring thrombolysis under flow conditions using a newly developed microchip-based flow-chamber assay. Human blood samples from healthy volunteers were exposed to UA, alteplase, or a combination of UA and alteplase. Whole blood and platelet-rich plasma were perfused over a collagen- and thromboplastin-coated microchip, and capillary occlusion was monitored with a video microscope and flow-pressure sensor. The area under the curve (extent of thrombogenesis or thrombolysis) at 30 minutes was 92% lower in the UA–alteplase-treated group compared with the alteplase-treated group. D-dimers were measured to evaluate these effects in human platelet-poor plasma samples. Although hydrogen peroxide significantly decreased the elevation of D-dimers by alteplase, UA significantly inhibited the effect of hydrogen peroxide. Meanwhile, rat models of thromboembolic cerebral ischemia were treated with either alteplase or UA–alteplase combination therapy. Compared with alteplase alone, the combination therapy reduced the infarct volume and inhibited haemorrhagic transformation. UA enhances alteplase-mediated thrombolysis, potentially by preventing oxidative stress, which inhibits fibrinolysis by alteplase in thrombi.
Genome-wide RNA-seq analysis indicates that the DAG1 transcription factor promotes hypocotyl elongation acting on ABA, ethylene and auxin signaling
Authors: Lorrai Riccardo , Gandolfi Francesco , Boccaccini Alessandra , Ruta Veronica , Possenti Marco , Tramontano Anna , Costantino Paolo , Lepore Rosalba , Vittorioso Paola
Published: October 2018

Hypocotyl elongation is influenced by light and hormones, but the molecular mechanisms underlying this process are not yet fully elucidated. We had previously suggested that the Arabidopsis DOF transcription factor DAG1 may be a negative component of the mechanism of light-mediated inhibition of hypocotyl elongation, as light-grown dag1 knock-out mutant seedlings show significant shorter hypocotyls than the wild type. By using high-throughput RNA-seq, we compared the transcriptome profile of dag1 and wild type hypocotyls and seedlings. We identified more than 250 genes differentially expressed in dag1 hypocotyls, and their analysis suggests that DAG1 is involved in the promotion of hypocotyl elongation through the control of ABA, ethylene and auxin signaling. Consistently, ChIP-qPCR results show that DAG1 directly binds to the promoters of WRKY18 encoding a transcription factor involved in ABA signaling, of the ethylene- induced gene ETHYLENE RESPONSE FACTOR (ERF2), and of the SMALL AUXIN UP RNA 67 (SAUR67), an auxin-responding gene encoding a protein promoting hypocotyl cell expansion.
Intravital Two-photon Imaging of Ca2+ signaling in Secretory Organs of Yellow Cameleon Transgenic Mice
Authors: Jin Kai , Imada Toshihiro , Nakamura Shigeru , Izuta Yusuke , Oonishi Erina , Shibuya Michiko , Sakaguchi Hisayo , Adachi Takahiro , Tsubota Kazuo
Published: October 2018

Intracellular calcium ([Ca2+]i) signaling regulates physiological functions in most cells. In secretory organs, such as the pancreas, salivary gland, and lacrimal gland (LG), [Ca2+]i elevation in acinar cells triggers fluid secretion, which plays vital roles in the maintenance of functional health across the life-course. It is important to understand the secretory mechanism of secretory organs, but lack of analytic systems available for living animals limits the scope of research to gain deeper insights into the precise mechanism of secretion. We established an intravital imaging system for specific cell types of secretory organs to monitor the [Ca2+]i changes using mouse line expressing Yellow Cameleon 3.60, a genetically encoded Ca2+ indicator. Elevation of [Ca2+]i in specific cell types of secretory organs could be monitored after cholinergic stimulation ex vivo and intravitally. We found that a marked attenuation of LG [Ca2+]i response to cholinergic stimulation was induced under pathological conditions by postganglionic denervation. Intravital Ca2+ imaging in secretory organs will broaden our understanding of the cellular mechanisms in animal models of secretory diseases.
A family of molecular nickel hydrogen evolution catalysts providing tunable overpotentials using ligand-centered proton-coupled electron transfer paths
Authors: Aimoto Yutaro , Koshiba Keita , Yamauchi Kosei , Sakai Ken
Published: October 2018

The overpotential for H2 evolution from water can be rationally controlled by tuning the ligand-centered proton-coupled electron transfer (PCET) processes.
Mixed transitions in the UV photodissociation of propargyl chloride revealed by slice imaging and multireference ab initio calculations
Authors: Foley Casey D. , Joalland Baptiste , Alavi S. Tahereh , Suits Arthur G.
Published: October 2018

Resonance-enhanced multiphoton ionization (REMPI) and DC slice imaging were used to detect photoproducts Cl (2P3/2), spin–orbit excited Cl* (2P1/2), and C3H3 in the photodissociation of propargyl chloride at 212 and 236 nm.
Integration of sample preparation and analysis into an optofluidic chip for multi-target disease detection
Authors: Meena Gopikrishnan G. , Jain Aadhar , Parks Joshua W. , Stambaugh Alexandra , Patterson Jean L. , Hawkins Aaron R. , Schmidt Holger
Published: October 2018

This work presents an optofluidic platform with integrated optical waveguides combining complex sample preparation capabilities with the ability to detect individual DNA molecules on one single platform.
Multistage rocket: integrational design of a prodrug-based siRNA delivery system with sequential release for enhanced antitumor efficacy
Authors: Jiang Qian , Chen Xiaobing , Liang Hong , Nie Yu , Jin Rongrong , Barz Matthias , Yue Dong , Gu Zhongwei
Published: October 2018

The sequential release of siRNA and anticancer drug was realized in a novel dendritic peptide–prodrug.
An acidic pH/reduction dual-stimuli responsive nanoprobe for enhanced CT imaging of tumours in vivo
Authors: Wang Anna , Yin Ling , He Lei , Xia Huawei , Chen Fei , Zhao Meng , Ding Jianan , Shi Haibin
Published: October 2018

A smart acidic pH/glutathione (GSH) dual-stimuli responsive nanoprobe (1) was designed and synthesized herein. This probe could undergo intermolecular CBT condensation to form nanoparticle assembly in tumour microenvironment, resulting in enhanced tumour CT imaging.
In-memory direct processing based on nanoscale perpendicular magnetic tunnel junctions
Authors: Cao Kaihua , Cai Wenlong , Liu Yizheng , Li Huisong , Wei Jiaqi , Cui Hushan , He Xiaobin , Li Junjie , Zhao Chao , Zhao Weisheng
Published: October 2018

We experimentally demonstrated ‘stateful’ logic gates using two p-MTJs and realized “AND”, “OR”, “IMP”, and “NIMP” operations with only one cycle.
Real time bioimaging for mitochondria by taking the aggregation process of aggregation-induced emission near-infrared dyes with wash-free staining
Authors: Ren Fei , Liu Pai , Gao Yu , Shi Jianbing , Tong Bin , Cai Zhengxu , Dong Yuping
Published: October 2018

Triphenylpyrrole derivatives are designed for application in wash-free real-time mitochondrial imaging, which emit NIR signals and feature AIE characteristics.
High-performance quantum dot light-emitting diodes using chip-scale package structures with high reliability and wide color gamut for backlight displays
Authors: Lai Chun-Feng , Tien Yu-Chien , Tong Hung-Chun , Zhong Chang-Zhi , Lee Yu-Chun
Published: October 2018

In this study, for the first time, we propose CSP QD-LEDs with excellent stability, high color uniformity, and wide color gamut for backlight displays.
Rapid and visual readout of vitamin B1 based on the electrostatic interaction induced aggregation of gold nanoparticles
Authors: Lin Liping , Wang Jiajing , Liu Wei , Luo Yaxin , Xiao Yanling , Wang Yuhan
Published: October 2018

Schematic illustration for colorimetric detection of VB1 with AuNPs based on the electrostatic interaction.
Engineering of a TiO2 anode toward a record high Initial coulombic efficiency enabling high-performance low-temperature Na-ion hybrid capacitors
Authors: Kang Meiling , Wu Yingying , Huang Xin , Zhou Kaiqiang , Huang Zhigao , Hong Zhengsheng
Published: October 2018

A high-performance hybrid sodium-ion capacitor was developed through the engineering of a TiO2 anode to achieve record high initial coulombic efficiency.
Additive manufacturing with stimuli-responsive materials
Authors: Boydston A. J. , Cao B. , Nelson A. , Ono R. J. , Saha A. , Schwartz J. J. , Thrasher C. J.
Published: October 2018

Additive manufacturing, commonly referred to as 3D printing (3DP), has ushered in a new era of advanced manufacturing that is seemingly limited only by imagination.
Building a cycle-stable sulphur cathode by tailoring its redox reaction into a solid-phase conversion mechanism
Authors: He Feng , Wu Xiangjiang , Qian Jiangfeng , Cao Yuliang , Yang Hanxi , Ai Xinping , Xia Dingguo
Published: October 2018

A cycle-stable sulfur cathode with a solid-phase conversion mechanism is developed by building a SEI layer on S/C particles.
Ni1.5CoSe5 nanocubes embedded in 3D dual N-doped carbon network as advanced anode material in sodium-ion full cells with superior low-temperature and high-power properties
Authors: Wang Ying-Ying , Fan Haosen , Hou Bao-Hua , Rui Xian-Hong , Ning Qiu-Li , Cui Zheng , Guo Jin-Zhi , Yang Yang , Wu Xing-Long
Published: October 2018

An advanced anode for sodium-ion batteries is prepared by embedding cube-like Ni1.5CoSe5 nanoaggregates into 3D dual N-doped carbon network.
Direct and continuous hydrothermal flow synthesis of thermochromic phase pure monoclinic VO2 nanoparticles
Authors: Malarde Delphine , Johnson Ian D. , Godfrey Ian J. , Powell Michael J. , Cibin Giannantonio , Quesada-Cabrera Raul , Darr Jawwad A. , Carmalt Claire J. , Sankar Gopinathan , Parkin Ivan P. , Palgrave Robert G.
Published: October 2018

The first direct synthesis of pure thermochromic VO2(M) nanoparticles with particle sizes below 50 nm by continuous hydrothermal flow synthesis (CHFS).
Design of MWCNT bucky paper reinforced PANI–DBSA–DVB composites with superior electrical and mechanical properties
Authors: Sharma Sushant , Kumar Vipin , Pathak Abhishek K. , Yokozeki Tomohiro , Yadav Shailesh Kumar , Singh Vidya Nand , Dhakate S. R. , Singh Bhanu Pratap
Published: October 2018

High-strength conducting polymer composites are in high demand in modern aerospace and automobile industries.
A novel sensitive and stable surface enhanced Raman scattering substrate based on a MoS2 quantum dot/reduced graphene oxide hybrid system
Authors: Wu Di , Chen Jianli , Ruan Yaner , Sun Kai , Zhang Kehua , Xie Wenjie , Xie Fazhi , Zhao Xiaoli , Wang Xiufang
Published: October 2018

A MoS2 QD/rGO nanocomposite is synthesized as a novel highly sensitive and stable surface SERS substrate for dye molecular detection.
Analysis for reference sensor selection in time difference of arrival‐based localisation
Authors: Xie Y. , Lee J.H. , Song T.L.
Published: October 2018

Target localisation methods using time difference of arrival measurements have to handle the correlated measurement noises caused by the common reference sensor. The noise correlation, as well as the reference sensor selection, impacts the Cramer–Rao lower bound and the target tracking result. This Letter proposes two theorems to analyse the effects of reference sensor selection theoretically. Simulation results validate the correctness of the proposed theorems.
Semi‐implicit FDTD TW scheme for modelling effective surface plasmons
Authors: Fujita K.
Published: October 2018

A semi‐implicit finite‐difference time‐domain thin‐wire (TW) scheme with a relaxed stability condition is proposed for modelling effective surface plasmons in waveguide metamaterials. Its formulation is based on introducing the Newmark‐Beta method into the TW formulation based on the contour‐path integral of Maxwell's equations around a wire. The resultant scheme is magnetically implicit. Its stability, accuracy and efficiency are assessed in the application to a wire‐added parallel‐plate waveguide perturbed with a small gap.
Compressed channel estimation methods for high mobility doubly selective channels in orthogonal frequency division multiplexing systems
Authors: Vahidi Vahid , Saberinia Ebrahim
Published: October 2018

In this study, four channel‐estimation (CE) methods are proposed for sparse high mobility doubly selective channels. These methods are designed to take advantage of the sparsity of the channel to decrease the training sequence size and the computational complexity of the CE. Two of the new methods use time domain training sequences. In the first method, the pilot is designed such that the time domain channel can be estimated tap‐by‐tap using an autoregressive procedure. In the second method, a truncated Taylor expansion of the channel phase is applied to linearise the equations for CE and a pseudorandom training sequence is utilised to solve those equations. The last two proposed channel estimators employ frequency domain pilots and are built upon a previously proposed estimator that exploits both the delay and Doppler shift sparsity of the channel. The computational complexity and the spectral efficiency of the methods are compared. In addition, simulations are performed to compare the performance of these estimators in a sparse channel. Simulation results indicate up to 30 dB improvement in the bit error rate calculation for our proposed CE methods compared to the conventional CE methods.
Exponential stabilisation of positive singular linear discrete‐time delay systems with bounded control
Authors: Ngoc Phat Vu , Huu Sau Nguyen
Published: October 2018

Inspired by the results obtained in Liu et al. (2008, 2009), this study extends the constrained control problem to singular linear positive discrete‐time systems with delay. By using the singular value decomposition approach, delay‐dependent sufficient conditions for the regularity, causality, positivity and exponential stabilisation with a given decay rate of the system are established in terms of linear programming problem. A numerical example to demonstrate the effectiveness of the proposed method is given.
Overview of recent advances in stability of linear systems with time‐varying delays
Authors: Zhang Xian‐Ming , Han Qing‐Long , Seuret Alexandre , Gouaisbaut Frédéric , He Yong
Published: October 2018

This study provides an overview and in‐depth analysis of recent advances in stability of linear systems with time‐varying delays. First, recent developments of a delay convex analysis approach, a reciprocally convex approach and the construction of Lyapunov–Krasovskii functionals are reviewed insightfully. Second, in‐depth analysis of the Bessel–Legendre inequality and some affine integral inequalities is made, and recent stability results are also summarised, including stability criteria for three cases of a time‐varying delay, where information on the bounds of the time‐varying delay and its derivative is totally known, partly known and completely unknown, respectively. Third, a number of stability criteria are developed for the above three cases of the time‐varying delay by employing canonical Bessel–Legendre inequalities, together with augmented Lyapunov–Krasovskii functionals. It is shown through numerical examples that these stability criteria outperform some existing results. Finally, several challenging issues are pointed out to direct the near future research.
Practical stability and stabilisation of switched delay systems with non‐vanishing perturbations
Authors: Tian Yazhou , Sun Yuangong
Published: October 2018

This study addresses practical stability and stabilisation of switched delay systems with bounded non‐vanishing perturbations. By introducing a new method, i.e. the convergence theory of the geometric series, several stability and stabilisation criteria are derived under the average dwell switching. An example is also given to illustrate the effectiveness of the theoretical results.
Semi‐interior permanent‐magnet actuators for high‐magnet‐utilisation and low‐cost applications
Authors: Luo Ciyong , Sun Jun
Published: October 2018

Generally, for small‐ and medium‐sized tubular permanent‐magnet (PM) linear actuators, PM structures can be divided into two categories. One is interior PM (IPM) structure and the other is surface‐mounted PM (SPM), involving a compromise between flux per pole and magnet leakage flux. This study proposes a novel semi‐IPM (s‐IPM) structure for a tubular linear actuator having the advantages of high flux per pole of IPM and small magnet leakage flux of SPM. The air‐gap flux density and the average thrust are analysed and compared with IPM and SPM by the magnetic equivalent circuit and finite element analysis. Moreover, the s‐IPM structure is also compared with Halbach PM array in terms of the average thrust and the magnet utilisation. Four prototype actuators with different PM structures are built and tested. Both the theoretical and experimental results show that the magnet utilisation of the s‐IPM structure is the largest while its cost and volume are approximately unchanged. The proposed s‐IPM actuators are of great prominence in high‐magnet‐utilisation and low‐cost applications.
Smart solid‐state ferroresonance limiter for voltage transformers application: principle and test results
Authors: Heidary Amir , Radmanesh Hamid
Published: October 2018

This study employs a novel smart solid state ferroresonance limiter (SSFL) for stabilising the chaotic behaviour of a voltage transformer (VT). It is shownthat the ferroresonance overvoltage in VTs includes some resonance modes that can be classified as a fundamental, sub‐harmonic and chaotic oscillations. The effects of the suggested SSFL on decreasing the amplitude of the ferroresonance over‐voltages are examined. To confirm the simulation results, a laboratory prototype is implemented and tested. The performance of the suggested SSFL is simulated using MATLAB software and experimental results are compared with the simulation results. The measurement and experimental results are in agreement and clearly show the ability of the suggested SSFL on ferroresonance cancellation and VT protection against the occurred overvoltage.
Non‐isolated high gain DC–DC converter with low device stress and input current ripple
Authors: Sri Revathi B. , Mahalingam Prabhakar
Published: October 2018

In this article, a novel DC–DC converter with high voltage gain capability is presented. The proposed converter is synthesised from (i) a basic two‐phase interleaved boost converter (IBC) which uses coupled inductors (CIs) instead of discrete inductors and (ii) diode‐capacitor multiplier (DCM) cells to achieve higher voltage conversion ratio. The outputs obtained from the interleaved and the DCM stages are judiciously cascaded with the outputs obtained from the secondary winding of the CIs to enhance the voltage gain. The input current is almost ripple free due to the adopted interleaving mechanism. As voltage gain is extended using CIs and DCMs, the voltage stress on the semiconductor devices is minimal and only a fraction (10.5%) of the output voltage. Experimental results obtained from the 18 V/380 V, 150 W prototype converter, operating at a maximum efficiency of 94% under full‐load condition, validate the proposed concept. Further, practical results obtained under closed‐loop condition confirm that the converter yields a constant output of 380 V DC which is suitable for microgrid application.
Numerical simulation model of a reciprocating seal based on the mixed‐lubrication theory
Authors: Xiang Chong , Wang Zixi , Jia Xiaohong , Guo Fei
Published: October 2018

Based on the mixed‐lubrication theory, a numerical simulation model of a reciprocating seal is established. The model includes finite element, fluid mechanics, contact mechanics and deformation mechanics analyses. The hydrodynamic analysis uses elastohydrodynamic lubrication theory and inverse hydrodynamic lubrication to obtain the relationship between fluid pressure and film thickness, while the contact mechanics analysis obtains the relationship between the asperity contact pressure and film thickness. The influence of the coefficient matrix and static contact pressure is calculated by the finite element analysis. The coupling relationship among the fluid pressure, asperity contact pressure and static contact pressure is provided by the influence coefficient method of the deformation mechanics analysis. The calculation results of the numerical model are verified by experimental results, which are measured by the bench test developed by the authors.
Variable step strategy for online secondary path modelling in active vibration control systems
Authors: Yang Xiaojing , Hu Junwen , Li Shan
Published: October 2018

An online modelling method for secondary path of two distinct variable step‐size strategies based on the filtered‐x least square (FXLMS) algorithm is proposed. In this method, the variable step‐size strategy with two distinct steps is used, and two variable step‐size strategies are used before and after the secondary path modelling process converges, so that the convergence rate is guaranteed. At the same time, it can effectively avoid the fluctuation after the system converges and improve the stability and modelling accuracy of the system. Due to the white noise, the signal of secondary path modelling will affect the control part. A white noise control strategy is proposed to adjust the white noise according to the change of the step‐size of the secondary path. On the premise of ensuring identification speed and precision, the influence of white noise on the control part is eliminated as far as possible. Compared to the existing methods, the simulation result shows that the proposed method can significantly improve the modelling accuracy of the secondary path while ensuring the convergence speed and has a better performance in vibration control effects.
Numerical simulation and analysis of temperature and flow field of high‐speed axial piston motor pump
Authors: Gao Dianrong , Zhang Zongyi , Sun Yanan , Xu Senhao , Liu Jingcheng , Zhang Yan
Published: October 2018

Based on the theories of heat transfer and the method of computational fluid dynamics, a liquid–solid mathematical model of heat transfer of an axial piston hydraulic motor pump is constructed in this study. Through the finite volume method, the model with different cooling runners has been solved. Meanwhile, the oil flow regularity of runner and temperature distribution of the motor pump and oil duct has been obtained. On the basis of the model of long‐strip runner, the influence of ambient temperature on the motor pump's temperature rise has been analysed. The result shows that the cooling channels on the housing of the hydraulic motor pump effectively reduce the temperature rise, and a long‐strip channel is for optimum cooling. The average temperature rise of the motor pump increases linearly with the increase of ambient temperature.
Parameters and control optimisation of hybrid vehicle based on simulation model
Authors: Wang Jiayi , Liu Xinhui , Wang Xin , Sun Kui , Zheng Boyuan
Published: October 2018

It is generally difficult to obtain accurate optimisation functions during parameters matching and optimisation process of the hybrid system, especially in the optimisation variable field containing both a continuous set and a discontinuous set and when the control strategy has an important influence on the system performance. To aim at the fuel economy of the parallel hydraulic hybrid system, a global parameter matching and control strategy based on the simulation model were proposed. The AMESim simulation model as the judgment module of the optimisation algorithm was used to match and optimise the main parameters and control strategies in the hybrid system. The communication of underlying parameters was developed by the VBA in EXCEL platform. Parameters match was implemented on a truck crane chassis in practice. The test results indicated that the rate of fuel saving reached 15.2%, which was generally consistent with the theoretical analysis. The parameters were met the energy‐saving requirements of hybrid vehicles.
Design and optimisation of cushioning structure of hydraulic free‐piston engine
Authors: Chen Qihuai , Ren Haoling , Lin Tianliang , Miao Cheng , Fu Shengjie
Published: October 2018

The velocity of the free‐piston assembly (FPA) of the hydraulic free‐piston engine (HFPE) is very high, which is up to 10 m/s. In order to avoid the collision of the FPA to the cylinder head when the FPA moves towards the dead centres, the cushioning device must be involved. A cushioning structure which combines the sidestep‐shape cushion and flute‐shape cushion is proposed according to the working principle of the HFPE. The mathematical model of the cushioning is set up, and key parameters are obtained. AMESim is employed to analyse the cushioning process and the influence of the key parameters on the cushioning process. The optimised parameters are obtained according to the simulation. The test rig is established to verify the effectiveness of the cushioning structure according to the optimised parameters. The experiment results show that the proposed cushioning structure is reliable. The maximum pressure during the cushioning process is 19 MPa, and cushioning time is 12 ms. The cushioning structure has little influence on the starting process of HFPE.
Research on low‐speed performance of continuous rotary electro‐hydraulic servo motor based on robust control with Adaboost prediction
Authors: Jing Wang X. , Zhen Liu M. , Wei Sun Y. , Wang Xin
Published: October 2018

In order to improve the robustness and low‐speed performance of continuous rotary electro‐hydraulic servo system under influences of dynamic uncertainties, parametric perturbation, friction, other non‐linear properties, and uncertainties, the robust control strategy was proposed with Adaboost prediction. Firstly, basing on the system mathematic model, the model with structured uncertainty and generalised state equation was established with parametric perturbation and external disturbances, and then the robust controller was developed by adopting theory. Furthermore, Adaboost algorithm based on radial basis function (RBF) neural network was applied to design the system feedback mechanism, so the multiple weak neural network learners were obtained by using Adaboost algorithm to train system actual output and input. Also, these weak neural network learners constituted a strong learner to predict the electro‐hydraulic servo system output and calculate the predictive error so as to adjust the system robust control output, so the real‐time control was carried out by the robust controller. Some comparative simulated results are obtained to verify the proposed controller guarantees performances of low speed, tracking accuracy, and ability of anti‐interference, which greatly expands the band of frequency response and improve the system robustness.
Research on geometrical parameters effect of fan nozzle jet performance based on orthogonal experiment
Authors: Shi Xudong , Jiang Guijia , Wei Bing , Kong Xiangfen
Published: October 2018

In order to determine the significance and importance order of the jet performance caused by fan nozzle's geometric parameters of aero‐engine online cleaning equipment, the orthogonal experiment method, standard k –ɛ turbulence model and volume of fluid (VOF) two‐phase flow algorithm are used to research the jet of fan nozzle. The sensitivity of nozzle contraction angle, nozzle area ratio, nozzle incision angle, nozzle exit thickness and offset to the influence of fan nozzle spray angle was verified by range analysis and variance analysis. The results of the two analysis methods consistently show that the main order of influence of the geometric parameters of fan nozzle on spray angle is nozzle area ratio, nozzle incision angle, nozzle exit thickness, offset and nozzle convergence angle. The former two have more influence on the spray angle than the others. Finally, the simulation results and orthogonal test results are verified by the injection experiment of the fan nozzle. The jet shape is mainly determined by the nozzle area ratio and incision angle. The larger the incision angle and the nozzle area ratio are, the smaller the spray angle becomes.
Research on flow characteristics of aerostatic circular thrust bearing
Authors: Yu Hechun , Wang Guangzhou , Ma Wenqi , Zhang Guoqing , Zhao Zexiang
Published: October 2018

In order to improve the pressure distribution, the aerostatic circular thrust bearing with single supply hole was studied. In the computational fluid dynamics (CFD) simulation, the laminar model, the turbulent model, the mixture model of laminar and turbulent were used simultaneously. The micro‐characteristics of the gas flows were analysed based on the simulation results. One test rig was built for measuring the pressure distribution with the single test hole, and the calculated and experimental results were compared. The results showed that when the gas film clearance is small and the gas flow is subsonic completely, the whole gas flow is laminar flow, which should be calculated based on the laminar model and when the gas film thickness is large and there is supersonic flow in some region, which should be calculated according to the mixture model; at the same time, there is no surface of discontinuity for Mach number and pressure distribution, and no shock, and the pressure is recovered due to the boundary layer separation, the change of the flow state and the change of viscosity. The method for testing the pressure distributions with a single test hole is effective.
Semi‐physical real‐time control of electro‐hydraulic proportional position servo system based on Matlab/xPC
Authors: He Zhenxin , Feng Yongbao , Liu Yuan , Li Liang , Ma Changlin , Wang Hao
Published: October 2018

A set of semi‐physical simulation system based on real‐time working simulation platform tools (Matlab/RTW) was established for electro‐hydraulic proportional position servo system in the development of missile weapons and other equipment. The system is mainly composed of hydraulic system consisting of hydraulic actuators and Simulink simulation model. It is a closed‐loop real‐time simulation system of physical equipment in the loop. The simulation and experiment of proportional servo control system show that the system has high simulation real‐time performance, the positioning accuracy and control stability. Two controllers are designed for different application conditions, which can obtain the good practicality and feasibility.
Improved design and parameter optimisation of the transmission mechanism of a tobacco stalk pull‐out crusher
Authors: Zhang Dabin , Shu Chengsong , Zhang Yuanchang , Zhang Yunfei , Wei Jianyu
Published: October 2018

In order to eliminate the plug stem phenomenon and reduce the transmission power consumption of the self‐developed integrated tobacco stalk pull‐out crusher transmission mechanism when the culms are pulled out at high speed in the field, based on the analysis of the reasons of plug stem, a new rubber‐type roller pair transmission mechanism with easy disassembly and adjustable spacing was designed. Through the force analysis, the mathematical model of the force, deformation and transmission power of the tobacco stalk during the extrusion and transportation phase was obtained, and the test platform of the tobacco stalk pull‐out crusher transmission mechanism was built to carry out the orthogonal rotation combination test. The test results show that the optimal working parameter combination within the range of test factors is: the roller speed is 530 r/min, the II pair of roller spacing is 90 mm, the III pair of roller spacing is 30 mm, and the tobacco stalk feeding rate is 1.5 s/n. At this time, the plugging rate of stem is 2.22%, the transmission power consumption is 645 W, and the actual average leak stalk rate obtained by repeating 10 tests under this parameter is 3.33%, and the actual transmission power consumption is 684 W, the actual plugging rate of stem and transmission power are basically consistent with the optimized values, indicating that the improved design structure is reasonable, and the established regression model is basically reliable.
PID–PFC control of continuous rotary electro‐hydraulic servo motor applied to flight simulator
Authors: Jing Wang X. , Zhen Liu M. , Shuai Chen , Hao Liu , Wang Xin
Published: October 2018

Due to the uncertainties caused by high non‐linearity, friction, leakage and other external factors existing in the flight simulator with continuous rotary electro‐hydraulic servo motor and the traditional control strategies discontenting with the high‐performance requirements, the mathematical model of continuous rotary electro‐hydraulic position servo system is established and the compound control theory combining proportional‐integral‐derivative (PID) and the predictive function control (PFC) method is proposed. In order to enable the servo system to estimate the influence of uncertainties and correct it by repeating online optimisation continuously, PID–PFC compound controller basing on the structure of internal model control is designed and then applied to continuous rotary electro hydraulic servo system. The simulation results show that compared with the traditional PID, PFC controller, PID–PFC compound control can effectively inhibit the interferences of the electro‐hydraulic servo system, and greatly improve the response speed and tracking performances and expanding the system frequency band width. The accurate control of motor's position can be realised by applying PID–PFC compound control, which can make the servo system has stronger robustness.
Reliability analysis of tractor multi‐way valves based on the improved weighted grey relational method
Authors: Xu Liping , Ma Haoyi , Ren Dezhi
Published: October 2018

In order to analyse the influence of different performance indexes on the working reliability of a tractor multi‐way valve. The grey correlation theory is introduced into the reliability analysis of multi‐way valves. Combined with the multi‐way valve failure mode, the reliability index is proposed, and then a grey relational model and the reliability evaluation sequence of multi‐way valves are established. The reliability of multi‐way valve is analysed by traditional grey relational analysis and improved weighted grey correlation analysis, respectively. Although both methods produced the same optimal prototype, the dynamic identification coefficient introduced by the latter can effectively suppress the influence of singular values on the correlation sequence in the prototype sequence. The analysis process is simplified, and the accuracy of calculation is improved. Meanwhile, the identification degree of the sequence of the prototype is increased. In addition, the improved weighted grey relational analysis method uses the entropy weight method to assign weight coefficients. This method can reflect the influence degree of different sequence points on the overall correlation degree objectively and improve the reliability of the analysis results. Finally, the correctness of the optimal prototype is verified by comparing the experimental data. The reliability evaluation standard of the tractor multi‐way valve is obtained.
Combined motion control of hydraulic boom based on dynamic surface adaptive fuzzy sliding mode
Authors: Pan Rongan , Du Wenzheng , He Zhenxin , Jiang Yue , Wang Jie
Published: October 2018

The lifting mechanism on the transfer vehicle is a common electromechanical–hydraulic system. In order to overcome the non‐linear and interference that exist in the hydraulic boom combined motion process, a dynamic surface adaptive fuzzy sliding mode control method is proposed. The Lyapunov function and virtual control base on inversion of the sliding mode control are designed, the dynamic surface control is used to calculate the derivative of the virtual control, and the adaptive control is applied to estimate the parameter. Furthermore, the fuzzy control is applied to fuzzification the switching item of the sliding surface. Verified by simulation, the designed sliding mode controller has high control accuracy and strong robustness and eliminates system chatter.
Fermi/LAT counterparts of IceCube neutrinos above 100 TeV
Authors: Krauß F. , Deoskar K. , Baxter C. , Kadler M. , Kreter M. , Langejahn M. , Mannheim K. , Polko P. , Wang B. , Wilms J.
Published: October 2018

The IceCube Collaboration has published four years of data and the observed neutrino flux is significantly in excess of the expected atmospheric background. Due to the steeply falling atmospheric background spectrum, events at the highest energies are most likely extraterrestrial. In our previous approach we have studied blazars as the possible origin of the High-Energy Starting Events (HESE) neutrino events at PeV energies. In this work we extend our study to include all HESE neutrinos (which does not include IC 170922A) at or above a reconstructed energy of 100 TeV, but below 1 PeV. We study the X-ray andγ-ray data of all (∼200) 3LAC blazars that are positionally consistent with the neutrino events above 100 TeV to determine the maximum neutrino flux from these sources. This larger sample allows us to better constrain the scaling factor between the observed and maximum number of neutrino events. We find that when we consider a realistic neutrino spectrum and other factors, the number of neutrinos is in good agreement with the detected number of IceCube HESE events. We also show that there is no direct correlation betweenFermi/LATγ-ray flux and the IceCube neutrino flux and that the expected number of neutrinos is consistent with the non-detection of individual bright blazars.
Assessment: Upper Extremity Motor Activity Log (UE MAL) – Den Gebrauch des betroffenen Arms beurteilen
Authors: Peter Viktoria
Published: October 2018

Das Interview „Upper Extremity Motor Activity Log“ eignet sich für Patienten in der Neuroreha, insbesondere für Menschen nach Schlaganfall. Es misst, wie oft und wie gut sie den mehr betroffenen Arm im Alltag einsetzen.