bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of a recombination-resistant coronavirus as a broadly applicable, rapidly implementable vaccine platform
Authors: Graham Rachel L. , Deming Damon J. , Deming Meagan E. , Yount Boyd L. , Baric Ralph S.
Published: October 2018

Emerging and re-emerging zoonotic viral diseases are major threats to global health, economic stability, and national security. Vaccines are key for reducing coronaviral disease burden; however, the utility of live-attenuated vaccines is limited by risks of reversion or repair. Because of their history of emergence events due to their prevalence in zoonotic pools, designing live-attenuated coronavirus vaccines that can be rapidly and broadly implemented is essential for outbreak preparedness. Here, we show that coronaviruses with completely rewired transcription regulatory networks (TRNs) are effective vaccines against SARS-CoV. The TRN-rewired viruses are attenuated and protect against lethal SARS-CoV challenge. While a 3-nt rewired TRN reverts via second-site mutation upon serial passage, a 7-nt rewired TRN is more stable, suggesting that a more extensively rewired TRN might be essential for avoiding growth selection. In summary, rewiring the TRN is a feasible strategy for limiting reversion in an effective live-attenuated coronavirus vaccine candidate that is potentially portable across the Nidovirales order.
Frustration wave order in iron(II) oxide spinels
Authors: Perversi Giuditta , Arevalo-Lopez Angel M. , Ritter Clemens , Attfield J. Paul
Published: October 2018

Frustrated magnetic materials can show unconventional correlations such as quantum spin liquid states and monopole excitations in spin ices. These phenomena are observed on uniformly frustrated lattices such as triangular, kagome or pyrochlore types, where all nearest neighbour interactions are equivalent. Here we report incommensurate long-range spin amplitude waves in the spinels Fe2GeO4 and γ-Fe2SiO4 at low temperatures, which indicate that the degree of frustration may itself be a fluctuating quantity that can spontaneously order without a lattice distortion as a ‘frustration wave’. Fe2GeO4 with propagation vector (2/3 + δ 2/3 + δ 0) has ordered Fe2+ moments that vary between fully saturated 4 μB and 0 values, consistent with a frustration wave order. γ-Fe2SiO4 has a more complex (¾ + δ ¾ + δ 0) order that coexists with an ordered spin ice phase. Dynamic orbital fluctuations are proposed to give rise to locally correlated patterns of ferromagnetic and antiferromagnetic interactions consistent with the observed orders.
Lipid profiling of C. elegans strains administered pro-longevity drugs and drug combinations
Authors: Admasu Tesfahun Dessale , Batchu Krishna Chaithanya , Ng Li Fang , Cazenave-Gassiot Amaury , Wenk Markus R. , Gruber Jan
Published: October 2018

We report the effect of four lifespan modifying drugs and of synergistic combinations of these drugs on lipid profile in Caenorhabditis elegans. We employ ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS) to compare the abundance of lipid species in treated and control animals. Adult nematodes were treated with rapamycin, rifampicin, psora-4 and allantoin and combinations of these compounds and the resulting change in lipid profiles, specifically in those of triacylglycerol (TAG), phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were determined. We quantified changes resulting from treatment with the drug combinations relative to untreated controls and relative to animals treated with each constituent single drugs. We further determined the dependence of changes in lipid profiles on genes known to affect lipid metabolism using strains carrying mutations in these pathways. In particular, we determined lipid profiles in a genetic model of caloric restriction (eat-2), a strain lacking homolog of TGFβ (daf-7) and in a strain lacking the SREBP/sbp-1 transcription factor.
Covalent affixation of histidine-tagged proteins tethered onto Ni-nitrilotriacetic acid sensors for enhanced surface plasmon resonance detection of small molecule drugs and kinetic studies of antibody/antigen interactions
Authors: Wang Xiaoying , Liu Qinghua , Tan Xiaofeng , Liu Luyao , Zhou Feimeng
Published: October 2018

Covalent affixation of histidine-tagged proteins tethered onto Ni-nitrilotriacetic acid sensors for enhanced surface plasmon resonance detection.
Transient binding promotes molecule penetration into mucin hydrogels by enhancing molecular partitioning
Authors: Marczynski Matthias , Käsdorf Benjamin T. , Altaner Bernhard , Wenzler Andreas , Gerland Ulrich , Lieleg Oliver
Published: October 2018

Charged, mucoadhesive molecules can penetrate mucin-based hydrogels such as native mucus with similar efficiency as inert, non-mucoadhesive molecules.
Potential of ultramicroporous metal–organic frameworks in CO2 clean-up
Authors: Shalini Sorout , Nandi Shyamapada , Justin Anita , Maity Rahul , Vaidhyanathan Ramanathan
Published: October 2018

This article explains the need for energy-efficient large-scale CO2 capture and briefly mentions the requirements for optimal solid sorbents for this application.
Mechanisms of action of Ru(ii) polypyridyl complexes in living cells upon light irradiation
Authors: Jakubaszek Marta , Goud Bruno , Ferrari Stefano , Gasser Gilles
Published: October 2018

This feature article provides an overview of the most in-depth biological studies on Ru(ii) polypyridyl complexes upon light activation.
Revisiting the intense NIR active bronzaphyrin, a 26-π aromatic expanded porphyrin: synthesis and structural analysis
Authors: Kishore M. V. Nanda , Panda Pradeepta K.
Published: October 2018

The first solid state structural elucidation done for bronzaphyrins via a new dithia-analogue reveals inversion of their thiophene rings, and crystal packing reveals four open dimeric trifluoroacetate [(CF3COO)2H]− moieties binding to the macrocycle in its protonated form via H bonding.
Recent advances in the total synthesis of gracilamine
Authors: Shi Yingbo , He Haibing , Gao Shuanhu
Published: October 2018

Gracilamine belongs to the Amaryllidaceae alkaloid group and has a unique five-ring skeleton. This review will summarize the synthetic studies of gracilamine, and hopes to bring new inspiration to the research of Amaryllidaceae alkaloids.
An intracellular diamine oxidase triggered hyperpolarized129Xe magnetic resonance biosensor
Authors: Zhang Bin , Guo Qianni , Luo Qing , Zhang Xiaoxiao , Zeng QingBin , Zhao Longhui , Yuan Yaping , Jiang Weiping , Yang Yunhuang , Liu Maili , Ye Chaohui , Zhou Xin
Published: October 2018

After an enzymatic reaction, the129Xe-MRI signal in CB6 lit up.
Core–shell like glass containing lanthanide doped nanocrystals for efficient luminescence
Authors: Liu Qunhuo , Tian Ying , Xiao Zhen , Zhang Jiawei , Tang Wenhua , Jing Xufeng , Zhang Junjie , Xu Shiqing
Published: October 2018

A core–shell like nanoarchitecture was constructed in Yb/Er ion and Yb/Ho SrTiO3 NC-codoped TZNB glass for efficient luminescence.
Ionic conductivity and local structural features in Ce1−xSmxO2−x/2
Authors: Presto S. , Artini C. , Pani M. , Carnasciali M. M. , Massardo S. , Viviani M.
Published: October 2018

Manuscript correlates microstructure and transport properties modification, which might suggest a way to prepare better performing SOFC electrolyte materials.
Structure-specific chiroptical responses of hollow gold nanoprisms
Authors: Hazra Bidhan , Dey Jyotirban , Chandra Manabendra
Published: October 2018

Chiroptical responses of plasmonic chiral nanostructures can be controllably tuned by judicious tailoring of their structural parameters.
Photo-irradiated E/Z isomerization reaction of star-shaped isomers containing two cyanostilbene arms with charge transfer excited states
Authors: Liu Jin , Li Weijun , Liu Minjie , Dong Yujie , Dai Yuyu , Song Qingbao , Wang Jianli , Zhang Cheng
Published: October 2018

The specific E/Z isomerization reaction of the cyanostilbene groups in two molecular arms.
Retraction: Novel Rh-substituted hexaaluminate catalysts for N2O decomposition
Authors: Lim Katie
Published: October 2018

Retraction of ‘Novel Rh-substituted hexaaluminate catalysts for N2O decomposition’ by R. Amrousse et al., Catal. Sci. Technol., 2016, 6, 438–441.
Experimental and theoretical study of dimer-of-dimers-type tetrarhodium(ii) complexes bridged by 1,4-benzenedicarboxylate linkers
Authors: Kataoka Yusuke , Arakawa Kazuki , Ueda Hikaru , Yano Natsumi , Kawamoto Tatsuya , Handa Makoto
Published: October 2018

Two dimer-of-dimers-type tetrarhodium complexes, [Rh4(piv)6(BDC)] and [Rh4(piv)6(F4BDC)], in which two paddlewheel-type dirhodium units are linked by dicarboxylate ligands, have been synthesized and characterized.
Dynamic oxygen shield eliminates cathode degradation in lithium–oxygen batteries
Authors: Liang Zhuojian , Zhou Yucun , Lu Yi-Chun
Published: October 2018

By manipulating the fluxes of reduced discharge mediator and oxygen, we effectively protect the cathode from oxygenated side reactions.
Physicochemical and oxidative stability of a soybean oleosome-based emulsion and itsin vitrodigestive fate as affected by (−)-epigallocatechin-3-gallate
Authors: Ding Jian , Xu Zejian , Qi Baokun , Jiang Lianzhou , Sui Xiaonan
Published: October 2018

Oleosomes, which are pre-emulsified oil bodies found naturally in plants, have excellent stability, therefore making their use more popular in the food industries.
Cardioprotection and natural polyphenols: an update of clinical and experimental studies
Authors: González Arbeláez Luisa F. , Ciocci Pardo Alejandro , Fantinelli Juliana C. , Schinella Guillermo R. , Mosca Susana M. , Ríos José-Luis
Published: October 2018

Mechanisms involved in ischemia–reperfusion injury.
Insight into the mechanisms controlling the chemical vapor generation of cadmium
Authors: Pitzalis Emanuela , Angelini Davide , Mascherpa Marco Carlo , D'Ulivo Alessandro
Published: October 2018

Mechanisms controlling the chemical vapor generation of cadmium have been identified.
Degradable silver-based nanoplatform for synergistic cancer starving-like/metal ion therapy
Authors: Zhang Yifan , Yang Yichen , Jiang Shanshan , Li Fan , Lin Jing , Wang Tianfu , Huang Peng
Published: October 2018

Inspired by the chain reactions among silver nanoparticles, glucose oxidase (GOx) and intratumoral glucose, a degradable silver-based nanoplatform was developed for synergistic cancer starving-like/metal ion therapy.
Long rigid ligand induced basket-type phosphomolybdate photo-/electro-catalytic materials
Authors: Meng Fan-xue , Lv Jing-hua , Yu Kai , Zhang Mao-lin , Wang Kun-peng , Zhou Bai-bin
Published: October 2018

Two long rigid ligands are introduced into {P6Mo18O73} systems, leading to two unique supramolecular hybrid assemblies, which show highly efficient catalytic activity for the degradation of refractory dye AP under UV light and bifunctional electrocatalytic behavior for the oxidation of dopamine (DA) and reduction of H2O2.
Synthesis of pyrrolo[3,4-c]quinoline-1,3-diones: a sequential oxidative annulation followed by dehydrogenation andN-demethylation strategy
Authors: Sharma Kumud , Das Babulal , Gogoi Pranjal
Published: October 2018

A synthetic strategy for pyrrolo[3,4-c]quinoline-1,3-dionesviaoxidative annulation followed by DDQ mediated dehydrogenation andN-demethylation.
Tetracyclo(9-methyl-2,7-carbazole) as a promising nanohoop for gas trapping: a multiscale study
Authors: Mohanty Biswajit , Venkataramanan Natarajan Sathiyamoorthy
Published: October 2018

H2S, CS2, NO2, Br2, HF, and C2H6are the ideal adsorbates within the TCC host from their respective congeners.
Water-soluble MoS2 quantum dots for facile and sensitive fluorescence sensing of alkaline phosphatase activity in serum and live cells based on the inner filter effect
Authors: Zhong Yaping , Xue Fengfeng , Wei Peng , Li Ruohan , Cao Chunyan , Yi Tao
Published: October 2018

We report a facile and sensitive method for the detection of alkaline phosphatase (ALP) activity in serum and live cells using molybdenum disulfide quantum dots (MoS2 QDs) based on the Inner Filter Effect (IFE).
Enhanced thermal conductivity in percolating nanocomposites: a molecular dynamics investigation
Authors: Termentzidis Konstantinos , Giordano Valentina M. , Katsikini Maria , Paloura Eleni , Pernot Gilles , Verdier Maxime , Lacroix David , Karakostas Ioannis , Kioseoglou Joseph
Published: October 2018

In this work we present a molecular dynamics investigation of thermal transport in a silica–gallium nitride nanocomposite.
Hierarchical manganese dioxide nanoflowers enable accurate ratiometric fluorescence enzyme-linked immunosorbent assay
Authors: Jiao Lei , Zhang Lianhua , Du Wenwen , Li He , Yang Dingyu , Zhu Chengzhou
Published: October 2018

We first developed a green, mild and rapid method for the preparation of hierarchical manganese dioxide nanoflowers (MnO2 NFs) as nanozymes with intrinsic oxidase-like activity using citric acid for the reduction of potassium permanganate.
An o-phthalimide-based multistimuli-responsive aggregation-induced emission (AIE) system
Authors: He Yanling , Li Yuanyuan , Su Huifang , Si Yue , Liu Yuanyuan , Peng Qiuchen , He Juan , Hou Hongwei , Li Kai
Published: October 2018

An o-phthalimide-based AIE system was developed and used for detecting UV light, Hg(ii) and pH, and as a photo-printing material.
Resveratrol metabolites ameliorate insulin resistance in HepG2 hepatocytes by modulating IRS-1/AMPK
Authors: Teng Wendi , Yin Wenjing , Zhao Liang , Ma Changwei , Huang Jiaqiang , Ren Fazheng
Published: October 2018

RSV metabolites R3G and R4G protected HepG2 cell from insulin resistance by improving glucose uptake and glycogen synthesis, along with inhibiting ROS generation and modulating the RS-1/AMPK signaling pathway.
A dipodal molecular probe for naked eye detection of trivalent cations (Al3+, Fe3+and Cr3+) in aqueous medium and its applications in real sample analysis and molecular logic gates
Authors: Chandra Rukmani , Manna Amit Kumar , Rout Kalyani , Mondal Jahangir , Patra Goutam K.
Published: October 2018

A dipodal reversible colorimetric trivalent metal ion chemosensor (L) has been designed and synthesized. The chemosensor L successfully detects Al3+, Fe3+ and Cr3+ based on binding site-signaling approach and it has practical application.
Asymmetric synthesis of (−)-naltrexone
Authors: Dongbang Sun , Pedersen Blaine , Ellman Jonathan A.
Published: October 2018

The asymmetric synthesis of (−)-naltrexone was achieved by a Rh(i)-catalyzed C–H alkenylation and torquoselective electrocyclization cascade and late-stage C–H hydroxylation.
A computationally designed binding mode flip leads to a novel class of potent tri-vector cyclophilin inhibitors
Authors: De Simone Alessio , Georgiou Charis , Ioannidis Harris , Gupta Arun A. , Juárez-Jiménez Jordi , Doughty-Shenton Dahlia , Blackburn Elizabeth A. , Wear Martin A. , Richards Jonathan P. , Barlow Paul N. , Carragher Neil , Walkinshaw Malcolm D. , Hulme Alison N. , Michel Julien
Published: October 2018

Molecular simulations led to the discovery of a new class of small molecules that inhibit the cyclophilin family of proteins.
A highly soluble, crystalline covalent organic framework compatible with device implementation
Authors: Wang Lingling , Zeng Cheng , Xu Hong , Yin Panchao , Chen Dongcheng , Deng Jian , Li Mu , Zheng Nan , Gu Cheng , Ma Yuguang
Published: October 2018

We report a soluble yet crystalline covalent organic framework (COF) by regulation of inter-layer interactions, which endows the COF with remarkable solubility and processability of thin films for optoelectronic devices that exhibit high yet anisotropic conductivities and outperform all the other COF-based semiconductors.
MOF-derived and nitrogen-doped ZnSe polyhedra encapsulated by reduced graphene oxide as the anode for lithium and sodium storage
Authors: Liu Xiaobin , Liu Yongchang , Feng Ming , Fan Li-Zhen
Published: October 2018

MOF-derived and nitrogen-doped ZnSe@rGO composites have been fabricated as high-performance Li/Na-storage anode materials.
A pH-responsive self-healing hydrogel based on multivalent coordination of Ni2+ with polyhistidine-terminated PEG and IDA-modified oligochitosan
Authors: Tang Quan , Zhao Dinglei , Yang Haiyang , Wang Lijun , Zhang Xingyuan
Published: October 2018

A multivalent Ni2+ coordination hydrogel based on polyhistidine-terminated PEG and IDA-modified oligochitosan with enhanced neutral stability and mild-acid responsiveness is reported herein.
Ultrahigh energy storage density and instantaneous discharge power density in BaO–PbO–Na2O–Nb2O5–SiO2–Al2O3 glass-ceramics
Authors: Wang Shujian , Tian Jia , Liu Jingran , Yang Ke , Shen Bo , Zhai Jiwei
Published: October 2018

An ultrahigh energy storage density Es of 20.7 J cm−3 and a maximum instantaneous power density of 78.2 MW cm−3 were obtained in BPNN-AS glass-ceramics.
Ultrasensitive photodetectors based on a high-quality LiInSe2 single crystal
Authors: Jia Ning , Wang Shanpeng , Wang Pengfei , Li Chunlong , Yu TongTong , Qiao Jie , Li Chenning , Xiong Xixi , Sun Jia-Lin , Tao Xutang
Published: October 2018

An ultrasensitive photodetector based on high-quality LiInSe2 (LISe) was systemically investigated. The device exhibited a high on/off current ratio, high detectivity, fast response speed, and high stability. This work may lay the foundation and ignite future research interest on LISe in photodetection.
An overview of lead-free piezoelectric materials and devices
Authors: Wei Huige , Wang Hui , Xia Yijie , Cui Dapeng , Shi Yapeng , Dong Mengyao , Liu Chuntai , Ding Tao , Zhang Jiaoxia , Ma Yong , Wang Ning , Wang Zicheng , Sun Ye , Wei Renbo , Guo Zhanhu
Published: October 2018

Lead-free piezoelectric materials and innovative piezoelectric devices provide a solution to the energy and environmental crisis we are now faced with.
Efficiency improvement of planar perovskite solar cells using a phenol additive
Authors: Fu Jiehao , Sun Kuan , Yang Ke , Hu Lijun , Leng Chongqian , Kan Zhipeng , Duan Tainan , Li Meng , Shi Haofei , Xiao Zeyun , Lu Shirong , Ouyang Jianyong
Published: October 2018

Phenol is introduced as a less-stringent solvent additive to improve the efficiency of perovskite solar cells.
Structural biology of 11-cis-retinaldehyde production in the classical visual cycle
Authors: Daruwalla Anahita , Choi Elliot H. , Palczewski Krzysztof , Kiser Philip D.
Published: October 2018

The vitamin A derivative 11-cis-retinaldehyde plays a pivotal role in vertebrate vision by serving as the chromophore of rod and cone visual pigments. In the initial step of vision, a photon is absorbed by this chromophore resulting in its isomerization to an all-trans state and consequent activation of the visual pigment and phototransduction cascade. Spent chromophore is released from the pigments through hydrolysis. Subsequent photon detection requires the delivery of regenerated 11-cis-retinaldehyde to the visual pigment. This trans–cis conversion is achieved through a process known as the visual cycle. In this review, we will discuss the enzymes, binding proteins and transporters that enable the visual pigment renewal process with a focus on advances made during the past decade in our understanding of their structural biology.
LncRNA BDNF-AS is associated with the malignant status and regulates cell proliferation and apoptosis in osteosarcoma
Authors: Huang Qiang , Yang Jiao , He Xin , Shi Shuyan , Xing Shuxing
Published: October 2018

Long non-coding RNA (LncRNA) brain-derived neurotrophic factor antisense (BDNF-AS) has been found to be down-regulated and function in a tumor suppressive role in human cancers. However, the expression status and function of BDNF-AS is still unknown in osteosarcoma (OS). In our study, BDNF-AS expression was found to be decreased in OS tissues and cells. Moreover, BDNF-AS low expression was correlated with advanced Enneking stage, large tumor size and poor prognosis in OS patients. The multivariate analysis suggested low expression of BDNF-AS was an independent unfavorable prognostic factor for overall survival in OS patients. The in vitro studies indicated that BDNF-AS overexpression inhibits OS cell proliferation and promotes cell apoptosis through regulating cleaved caspase-3. In conclusion, BDNF-AS serves as a tumor suppressive lncRNA in OS.
On‐line vehicle detection at nighttime‐based tail‐light pairing with saliency detection in the multi‐lane intersection
Authors: Gao Fei , Ge Yisu , Lu Shufang , Zhang Yuanming
Published: October 2018

A nighttime vehicle detection method in the multi‐lane intersection has been proposed based on saliency detection for traffic surveillance system in this study. Frame difference method is applied to detect moving objects at first, and all the rear lights of vehicles are extracted based on saliency map and colour information. Second, vehicles are detected through pairing off all the lamps, which include such steps as rechecking tail‐lamp pairs by using prior knowledge, eliminating repaired tail‐lamps on the same vehicle and removing the paired lamps across two lanes. Furthermore, to detect the vehicles that only have a single valid tail‐lamp, a proving approach for virtual tail‐lamp is investigated. Finally, the proposed method is verified to be more reliable and faster for nighttime vehicle detection by comparing with other detection methods, which can satisfy real‐time requirements of a vehicle detection system with good performance.
Cooperative look‐ahead control of vehicle platoon travelling on a road with varying slopes
Authors: Zhai Chunjie , Luo Fei , Liu Yonggui
Published: October 2018

In the current literature, little research has been done in the eco‐driving of vehicle platoon. To increase the fuel efficiency of vehicle platoon and ensure vehicle safety, this study proposes a switching control strategy for vehicle platoon travelling on a road with varying slopes, where the platooning and eco‐driving technologies are used. To improve the fuel efficiency of vehicle platoon, the cooperative look‐ahead controller is proposed by formulating a cooperative look‐ahead control problem of vehicle platoon based on distributed model predictive control (CLCbDMPC), which is a constrained nonlinear non‐convex multi‐objective optimisation problem. To solve the CLCbDMPC problem quickly, after the minimum fuel consumption table and its corresponding optimal reduction gear ratio table are constructed and calculated off‐line, the improved particle swarm optimisation algorithm with multiple dynamic populations is presented. Furthermore, the safety controller acting as the emergency brake to guarantee vehicle safety is also designed. The switch between the look‐ahead controller and the safety controller forms the switching control strategy of vehicle platoon. Simulation results demonstrate, compared with benchmarks, the proposed strategy can significantly save up to 21.88% of fuel for vehicle platoon, and vehicle safety can also be guaranteed.
Hybrid approach for immunisation of DFT‐based phasor estimation method against decaying DC components
Authors: Allahbakhshi Mehdi , Tajdinian Mohsen , Seifi Ali Reza , Zareian Jahromi Mehdi , Bagheri Alireza
Published: October 2018

In addition to high‐order harmonic and noise components, the fault current may contain decaying DC components which highly affect the estimated fundamental frequency phasor. This study presents a new hybrid method which aims to calculate and remove the unwanted effect of decaying DC components on fundamental phasor estimation. The main novelty of the proposed method is that the proposed method is independent of the dynamic behaviour of the current transformer (CT). In other words, unlike previously published papers, this method analytically calculates the CT time constant. To such aim, utilising frequency modulation, fault current signal is shifted. Utilising simple but comprehensive formulations based on integration and Prony‐complex theory, the magnitude and time constant of decaying DC components are calculated in one cycle. After that, utilising a modified discrete Fourier transform the fundamental phasor component is calculated. Several test signals and also practical fault signals are applied to the proposed method. The simulation results illustrate the proposed method simply but comprehensively remove the unwanted effects of the decaying DC components. Also, it has quick speed as well as a high‐precision response in the estimation of fundamental phasor under different simulation scenarios.
Workspace analysis for a five degrees of freedom hybrid engraving plotter
Authors: Chen Jiupeng , San Hongjun
Published: October 2018

At present, there is a little research on the workspace of the hybrid mechanism, and the further development of the engraving plotter is hindered due to the limitation of the workspace. In order to clearly understand the workspace of the hybrid engraving plotter, and verify whether the workspace meets the industrial production needs, the five degrees of freedom hybrid engraving plotter is analysed and studied. First, the structure of the engraving plotter is analysed and simplified, and then the direct equation is deduced by the analytic method. Second, according to the engraving plotter direct solution equation, the boundary of workspace is determined and the volume is calculated by using the optimisation algorithm. In order to understand the change of workspace in different z planes, the workspace of the parallel part is intercepted by some planes, which are parallel to XOY; thus, the authors know that the cut plane area of the workspace increases with the increase of Z values. Finally, the influence of the mechanism parameters is discussed on the dexterity. These theoretical knowledge will make important research significance for guiding engineering practice.
Structure of an ultrahigh internal pressure compound cylinder and its simulation by AMESim
Authors: Li Geqiang , Xv Yanli , Zhou Bin , Xie Keqiang , Hua Wanhong
Published: October 2018

This study presents an ultrahigh internal pressure compound booster cylinder and analyses the structure and principle of the cylinder. Its advantages include low input, high pressure output, and direct action on the execution cylinder. The model of the ultrahigh internal pressure compound booster cylinder is constructed by AMESim, and the result is analysed. By analysing the research and simulation results for this cylinder, the authors eventually designed an integrated composite hydraulic cylinder assembly that can realise the large pressure output of fast‐forward and quick return actions.
Hysteretic non‐linearity observer design and robust control for piezoelectric actuators
Authors: Hu Jiaming , Zhu Xiaojin , Fang Yubin , Gao Zhiyuan , Zhang Hesheng
Published: October 2018

The problem of tracking control for piezoelectric actuator (PEA) is investigated in this article. In consideration of that, the control precision of PEA is being restricted due to the hysteretic effect. For the purpose of improving the tracking performance, two issues are, respectively, taken into account – the compensation of the hysteretic effect and the controller design for the PEA system. To solve these problems, first, a new hysteresis observer based on sliding mode control theory is established. The design of the observer has considered the uncertainty in PEA modelling and the exogenous disturbance. Besides, according to Lyapunov theory, the hysteresis observer can asymptotically estimate the hysteretic character with performance. Second, a fault‐tolerant controller based on robust backstepping control theory is presented to make the PEA system to track the desire input. At last, numerical examples are given to verify the effectiveness of the proposed methods.
Study on dynamic characteristics analysis of CNC pipe thread lathe based on the energy of modal effective mass
Authors: Guang‐chen Xu , Xing‐wei Sun
Published: October 2018

Owing to the modal analysis of complex structure system exist in the problems such as the local mode cannot be identified and the overall modal vibration mode cannot be extracted, this study deduces a formula of modal effective parameters based on the kinetic energy and introduces to the simulation of mechanical characteristics of the SCK230 CNC pipe thread repair the lathe bed. The simulation shows that this method can identify the local mode of three directions effectively, and determines whether the numbers of solved modalities satisfy the requirement of precision. In order to improve the natural frequencies of the bed and analyse the influence of the opening of the bed on its dynamic performance, three optimisation schemes are proposed based on this, and verified the feasibility of the optimisation scheme. Through structural optimisation, improve the dynamic characteristic of the lathe bed and reduce the manufacturing cost, and the optimisation of the structure can be achieved without experimental modal analysis.
Application of electro‐hydraulic proportional control in cathode rod pulling out system of lead electrolysis
Authors: Song Bo , Yuan Ruibo , Yang Dajun
Published: October 2018

In the process of lead electrolysis, due to its production characteristics, it is necessary to extract and collect the cathode conductive rod on the cathode plate after electrolysis, so as to make it reusable. At present, most of the lead electrolytic manufacturers in China still rely on manual extraction in this process. In this study, a rapid, stable and effective cathode rod extraction equipment for lead electrolysis is designed by means of electro‐hydraulic proportional technology. AMESim simulation and experimental research on the equipment are also carried out.
Analysis and experimental validation of a pressure control method using magneto‐rheology fluid flows
Authors: Wang Fan , Guo Ning , Wang Linxiang
Published: October 2018

In this study, a spool actuating mechanism using controlled pressure difference is proposed for a large hydraulic servo valve. The actuating mechanism is accomplished by tuning magneto‐rheological (MR) fluid flow. The relationship between the flow rate and the controlled chamber pressure is obtained based on a non‐convex constitutive relation of the MR fluid. The control of the pressure difference by tuning the electrical flow is simulated. A series of experiments are carried out on a prototype system; the numerical and experimental results show that the proposed system can produce a very quick pressure change, which can be used to actuate the spool of the hydraulic servo valves for large flow rate applications.
Study on coordinated control of steering system for the hydraulic trucks combined transportation
Authors: Wang Jianjun , Zhao Jingyi , Zhou Jinsheng , Wang Yongchang , Cai Wei , Li Wenlei
Published: October 2018

For the transport of large‐tonnage equipment and structures, most of them use multiple hydraulic trucks to combine. The coordinated control of the hydraulic trucks’ hydraulic system groups is particularly important. The coordinated control of two hydraulic trucks from a company was studied during the steering of combined transportation. First, the hydraulic steering mechanism was analysed, and the functional relationship between steering angle and hydraulic cylinder stroke was obtained. Then, the synchronisation control strategy was compared and analysed, and the synchronous control mode with higher precision was selected. The mathematical model of the steering system was established, and the AMESim model and Simulink model were established to verify the feasibility of the control strategy. Finally, the steering tests of no load and full load were carried out. It was found that the actual test results were basically consistent with the simulation results. It was verified that the steering system with load‐sensing pump and master–slave coordinated PID control strategy can better realise coordinated steering action.
Influence of liquid film thickness on bearing characteristics of magnetic‐liquid suspension guide‐way
Authors: Zhao Jianhua , Zhang Bin , Chen Tao , Wang Qiang , Gao Dianrong
Published: October 2018

The magnetic‐liquid suspension guide‐way (MLSG) adopts the double support form of permanent magnetic suspension and hydrostatic pressure. It can greatly enhance the bearing capacity and rigidity of the guide‐way system. The liquid film thickness is the main influencing factor on both the bearing capacity of the hydrostatic system and the permanent magnetic force. This paper analysed the effect of liquid film thickness on the static, dynamic and vibration index of MLSG. Firstly, this paper introduced the structural characteristics and supporting mechanism of MLSG. Secondly, based on flow equation, the static pressure equation, the permanent magnetic force equation and the force balance equation, the transfer function of single DOF supporting system of MLSG in constant flow supply mode is presented, and analysed the influence of the thickness of liquid film on single DOF supporting performance of MLSG. The results show that with the increase of the thickness of the liquid film, the bearing capacity of guide‐way, the static stiffness, the dynamic stiffness and the natural frequency decrease, and the adjust time, the total power loss, the amplitude amplification coefficient increases, the phase margin is almost unchanged. The study can provide a theoretical basis for the design of MLGS in engineering practice.
Study on the effect of the pressure characteristics of the cone throttle on the cavitation
Authors: Zhang Jian , Duan Bosong , Jiang Jihai , Zhi Hui
Published: October 2018

According to the cone‐type throttle valve is prone to cavitation, resulting in the reduction in the performance of the cone throttle valve. Here, a visual experimental platform for hydraulic cavitation is built, and the cavitation number of the conical throttle valve under different working pressure, opening degree, and different back pressure is studied. The cavitation image under different conditions is obtained. The research shows that properly increasing back pressure, reducing system working pressure, and keeping small opening of the valve port can restrain cavitation.
Energy‐saving system of secondary balance for the hybrid power of the pumping unit
Authors: Li Chun‐shuang , Chen Lin , Wang Xin , Sun Kui , Liu Xin‐hui
Published: October 2018

The pumping unit is the main equipment for oil production in the oilfield. However, its serious energy consumption has greatly increased the cost of oil extraction. The reason of this phenomenon is the undesirable primary and secondary balance cannot make the motor run steadily in the high efficiency load rate interval, leading to low efficiency and great loss of the motor. In this paper, the secondary balance system for hydraulic hybrid power of pumping unit is developed, which can store the potential energy of the lower stroke in the accumulator and release it in the up stroke. It can effectively fill and reduce the wave valley and peak of the load rate curve, so that the motor can run in the high efficiency for a long time. The controller of the secondary balance system has a self‐learning method based on the multiple populations' genetic algorithms. It can reflect the real load by detecting the motor operating parameters, improving the response speed. At last, use AMEsim to simulate the hydraulic system, and compare the load fluctuation and motor energy consumption before and after setting energy‐saving system. It is proved that the energy saving effect of the system is extremely remarkable.
Analysis of internal flow field for a three‐stage centrifugal fan under various operating conditions
Authors: Ding Wensi , Chen Yuxun , Ding Yunke
Published: October 2018

Centrifugal fan in series is the core facility for pneumatic transportation. Its operation is required to be adjusted real time as the flow rate of transported materials changes. For optimisation performance, internal flow of a type 700 three‐stage fan at rated rotation speed is analysed with FLUENT6.3 for various total pressure. Multiple reference frame (MRF) model is used for the impellers rotation in simulation, and Re‐Normalisation group (RNG) κ‐ɛ turbulence model and Roe‐FDS flux type with first‐order upwind difference scheme are used for calculation of compressible flow under various total pressure. Flow characteristics are obtained and differences of total pressure and velocity distribution in every impeller are analysed in different conditions, and velocity distribution on meridian plane as well as section of wind guide plates and volute are compared. Results show that there are many vortexes and backflows in fan with higher total pressure, and the lower pressure, the more smoothly flows, besides flow at inlet and outlet of impellers and in guide plates is seriously influenced by total pressure. Curves of P ‐Q and P ‐η at 4600 r/min are predicted based on simulation, which is helpful reducing the impact caused by off‐design operation and improving efficiency.
Research on the planar‐coil linear time grating
Authors: Zhang Rui , Wu Liang , Peng Donglin , Liu Yang , Peng Lingli
Published: October 2018

This article proposes a planar‐coil linear time grating displacement sensor. Compared with the existing magnetic field‐type linear time grating, the structure without tooth and slot improves the velocity uniformity of travelling wave magnetic field and the measurement accuracy can be greatly improved. The two‐phase excitation coils are arranged to form a plane coil array, and the travelling wave magnetic field is generated after the two‐phase orthogonal signals are entered, respectively. Then, the electric travelling wave signal is induced by the pickup coils, and the displacement is obtained after processing. The signal processing circuit is designed to amplify and filter the electric travelling wave signal, and the accuracy experiment is carried out. Result shows that in the range of 240 mm (full‐scale), the measurement accuracy can achieve ±0.8 μm.
Uniform switched control strategy of valve‐controlled asymmetric hydraulic system
Authors: Yang Jun , Chen Zhongxiang , Zeng Le , Huang Shuzhou
Published: October 2018

Model set of a valve‐controlled asymmetric hydraulic system was built, and uniform switched control (USC) strategy was proposed for multi‐model set hydraulic system. Aiming at each subsystem model, the uniform feedback linearisation control (FLC) structure was put forward based on the FLC method, and switch control strategy was used by adjusting switch gain between different sub‐models. The boundary layer function was designed in order to enhance the system robustness and to reduce oscillation which is caused by discontinuous item. Furthermore, the switch control gain was further revised according to different load condition. At last, the USC, FLC control, and proportional differential (PD) control strategy was carried out by experiment, and the results show that the maximum speed tracking error of PD and FLC control was 1.1 and 1 mm/s, respectively. The USC strategy speed error is <0.25 mm/s. Compared with the PD and the FLC, the USC was found to be more speed accuracy in multiple state hydraulic system control.
Numerical simulation for multi‐way valves and fit clearance research based on heat–fluid–solid coupling
Authors: Xu Liping , Ma Haoyi , Ren Dezhi
Published: October 2018

It is difficult to accurately calculate the working load of the multi‐way valve of the crawler tractor in the traditional method. In practice, the spool and valve body are prone to over‐standard leakage and clamping problems in relative movement. This study analyses the mechanism of clamp and leakage problems caused by deformation, considering the influence of gradual change of oil channel diameter and direction change in the valve body caused by the throttling of the spool. Numerical simulation of heat–fluid–solid coupling for multi‐way valves is carried out. Under the condition of maximum pressure, the characteristic curve of material deformation of different spool and valve body changes with oil temperature is obtained. By evaluating the fitting characteristics of the spool and valve body of common materials, the optimal fit clearance is determined accurately. This effectively solves the contradiction between the clamping and leakage of the multi‐way valve and improves the performance of the multi‐way valve.
Synthesis of AgI/WS2 hybrids as a novel photocatalyst with efficient degradation of rhodamine B
Authors: Wu Xiang‐Feng , Li Hui , Zhang Ying , Zhang Jia‐Rui , Su Jun‐Zhang , Feng Yan‐Mei , Zhang Wei‐Guang , Sun Li‐Song , Sun Xiu‐Guo
Published: October 2018

Full‐spectrum‐responsive AgI/WS2 composites as an efficient photocatalyst have been synthesised by an in‐situ growth of AgI on the surfaces of WS2 nanosheets. The photocatalytic activities of the samples were evaluated by degradation of rhodamine B dilute solution under visible light irradiation. Experimental results showed that the introduction of WS2 nanosheets could enhance light absorption, photocatalytic activity, and recyclability of the pure AgI in the region of visible and infrared light. Moreover, the degradation efficiency of the as‐synthesised AgI/WS2 composites exhibited the trend of first increased and then decreased with increasing the amount of WS2 nanosheets. When the usage of WS2 nanosheets was 7 wt%, the as‐prepared composites possessed the maximum of 91.2% in 30 min. Furthermore, after three cycles of degradation, it could still degrade 89.0% of rhodamine B, obviously higher than 11.4% of pure AgI. In addition, a possible degradation mechanism of the as‐synthesised AgI/WS2 hybrids was provided.
High temperature high sensitivity optical fibre sensor based on multimode fibre Bragg grating
Authors: Lin Qijing , Zhao Na , Jiang Weile , Yao Kun , Tian Bian , Shi Peng , Chen Feng
Published: October 2018

A multimode fibre Bragg grating (MMFBG) is experimentally demonstrated in this work. The light from the lead‐in optical fibre transmits to the MMFBG, the Bragg gratings in multimode fibres show multiple reflection peaks due to the coupling among all bounded modes. Some reflection peaks are reflected back to the lead‐out fibre core by the MMFBG. Finally, the spatial frequency spectra of the reflection peaks are detected by the detection device. As the temperature variates, the changes in the transmission spectrum will be observed. Experimental results show that the MMFBG responds to temperature and the temperature sensitivity is 0.0114 nm/o C. The MMFBG has the advantages of compact structure, anti‐electromagnetic interference, and stable chemical property, which has great potential in temperature measurement.
PbS/IGZO hybrid structure photo‐field‐effect transistor with high performance
Authors: Meng Ying , Wang Jiawei , Ming Anjie , Wang Yinghui , Shi Xuewen , Li Molin , Wang Weibing , Li Ling
Published: October 2018

To optimise the performance of photo‐field‐effect transistor, a back‐gate hybrid structure was developed. In this hybrid phototransistor, lead sulphide (PbS) thin film was prepared using physical vapour deposition as a photosensitive layer. Discontinuous and uniform PbS film was obtained by controlling the deposition rate and time of PbS powders. Amorphous indium gallium zinc oxide (IGZO) with high mobility was used as an active layer. In this work, The hybrid structure phototransistor shows an excellent performance: device mobility (μ) reach 8.7 cm2 V−1 s−1, and responsivity achieve 2.7 × 104 A/W in visible spectrum and 5.7 A/W in near‐infrared spectrum, respectively. Furthermore, the transistor exhibits detectivity up to 2.79 × 1013 cmHz1/2 W−1. The device also exhibits characteristics of the ideal diode: the saturation current of the diode is as small as 0.422 nA, and the responsivity of diode is ∼0.74 A/W. Simplified manufacturing processes effectively reduce the cost of fabricated device and provide better device stability.
Facile synthesis of sesame‐husk‐like porous SnO2 nanocylinders as anodes for high‐performance lithium‐ion batteries
Authors: Dai Peng , Hu Haibo , Jiang Tongtong , Yu Xinxin , Bai Zhiman , Wu Mingzai
Published: October 2018

Sesame‐husk‐like porous SnO2 nanocylinders were synthesised by a refluxed technique followed calcination in air. Served as anode materials for lithium‐ion batteries, porous SnO2 nanocylinders showed a higher initial discharge capacity of 2411.3 mAh/g at 100 mA/g compared with non‐porous SnO2 nanocylinders (2043.6 mAh/g). Moreover, porous SnO2 nanocylinders demonstrated better cyclability and rate capability in comparison with non‐porous SnO2 nanocylinders. For porous SnO2 nanocylinders, a higher discharge capacity of 414.5 mAh/g after 50 cycles at a current density of 100 mA/g can be successfully delivered, and a higher reversible capacity of 248.3 mAh/g at 1000 mA/g current density after 100 cycles could be retained. The improved electrochemical performance is mainly ascribed to the unique porous nanostructures.
Forward modelling of brightness variations in Sun-like stars
Authors: Işık E. , Solanki S. K. , Krivova N. A. , Shapiro A. I.
Published: October 2018

Context. The latitudinal distribution of starspots deviates from the solar pattern with increasing rotation rate. Numerical simulations of magnetic flux emergence and transport can help model the observed stellar activity patterns and the associated brightness variations.

Aims. We set up a composite model for the processes of flux emergence and transport on Sun-like stars to simulate stellar brightness variations for various levels of magnetic activity and rotation rates.

Methods. Assuming that the distribution of magnetic flux at the base of the convection zone follows solar scaling relations, we calculate the emergence latitudes and tilt angles of bipolar regions at the surface for various rotation rates, using thin-flux-tube simulations. Taking these two quantities as input to a surface flux transport (SFT) model, we simulate the diffusive-advective evolution of the radial field at the stellar surface, including effects of active region nesting.

Results. As the rotation rate increases, (1) magnetic flux emerges at higher latitudes and an inactive gap opens around the equator, reaching a half-width of 20° for 8 Ω⊙; and (2) the tilt angles of freshly emerged bipolar regions show stronger variations with latitude. Polar spots can form at 8 Ω⊙ by accumulation of follower-polarity flux from decaying bipolar regions. From 4 Ω⊙ to 8 Ω⊙, the maximum spot coverage changes from 3 to 20%, respectively, compared to 0.4% in the solar model. Nesting of activity can lead to strongly non-axisymmetric spot distributions.

Conclusions. On Sun-like stars rotating at 8 Ω⊙ (Prot ≃ 3 days), polar spots can form, owing to higher levels of flux emergence rate and tilt angles. Defining spots by a threshold field strength yields global spot coverages that are roughly consistent with stellar observations.