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As a key skill for language learners, oral communication ability is one of the most important factors to measure one person’s overall quality. Being a widely used language, English has become an important communicative medium worldwide. Oral English teaching is an important part of the whole process of English learning and is generally an emerging topic for the education circle. However, the traditional oral English teaching model has no significant effect on improving oral English performance. Therefore, this paper studies the mixed oral English teaching model under the guidance of core qualities. The connotation of core literacy of oral English is analyzed and the general framework of the core literacy system of oral English is constructed. Then, the relationship between the four elements of English subject core literacy is examined based on the classification of the spoken English teaching resources. Next, the integration of spoken English teaching resources is realized and the oral English knowledge ontology and the cultural differences between Chinese and Western analysis are explored. Finally, a task-based oral English teaching hybrid model is developed. The experimental results show that there is a significant difference in the oral English level of the students before and after the experiment. The model can improve the overall quality and overall performance of English learning for our society.

All-optical magnetic switching promises ultrafast, high-resolution magnetisation control with the technological attraction of requiring no magnetic field. Existing all-optical switching schemes are driven by ultrafast transient effects, typically requiring power-hungry femtosecond-pulsed lasers and complex magnetic materials. Here, we demonstrate deterministic, all-optical magnetic switching in simple ferromagnetic nanomagnets (Ni$_{81}$Fe$_{19}$, Ni$_{50}$Fe$_{50}$) with sub-diffraction limit dimensions using a focused low-power, linearly-polarised continuous-wave laser. Isolated nanomagnets are switched across a range of dimensions, laser wavelengths and powers. All square-geometry artificial spin ice vertex configurations are written, including ground-state and energetically-unfavourable `monopole-like' states at powers as low as 2.74 mW. Usually, magnetic switching with linearly polarised light is symmetry-forbidden; however, here the laser spot has a similar size to the nanomagnets, producing an absorption distribution dependent on the relative nanoisland-spot displacement. We attribute the observed deterministic switching to the transient dynamics of this asymmetric absorption. No switching is observed in Co samples, suggesting the multi-species nature of NiFe alloys plays a role in reversal. The results presented here usher in cheap, low-power optically-controlled devices with impact across data storage, neuromorphic computation and reconfigurable magnonics.

The Raman scattering of light by molecular vibrations offers a powerful technique to 'fingerprint' molecules via their internal bonds and symmetries. Since Raman scattering is weak, methods to enhance, direct and harness it are highly desirable, e.g. through the use of optical cavities, waveguides, and surface enhanced Raman scattering (SERS). While SERS offers dramatic enhancements by localizing light within vanishingly small 'hot-spots' in metallic nanostructures, these tiny interaction volumes are only sensitive to few molecules, yielding weak signals that are difficult to detect. Here, we show that SERS from 4-Aminothiophenol (4-ATP) molecules bonded to a plasmonic gap waveguide is directed into a single mode with >99% efficiency. Although sacrificing a confinement dimension, we find 10$^4$ times SERS enhancement across a broad spectral range enabled by the waveguide's larger sensing volume and non-resonant mode. Remarkably, the waveguide-SERS (W-SERS) is bright enough to image Raman transport across the waveguides exposing the roles of nanofocusing and the Purcell effect. Emulating the $\beta$-factor from laser physics, the near unity Raman $\beta$-factor observed exposes the SERS technique in a new light and points to alternative routes to controlling Raman scattering. The ability of W-SERS to direct Raman scattering is relevant to Raman sensors based on integrated photonics with applications in gas and bio-sensing as well as healthcare., Comment: 12 pages, 4 figures in the main article; 12 pages, 7 figures in the supplementary information

8 pags., 5 figs., Mid-infrared spectroscopy is essential for chemical identification and compositional analysis because of the existence of characteristic molecular absorption fingerprints. However, it is very challenging to determine the refractive index of an analyte at low concentrations using current photonic systems in a broad mid-infrared spectral range. We propose an imaging-based nanophotonic technique for refractive index determination. The technique is based on deep subwavelength graphene plasmon nanocavities and allows for the retrieval of molecular concentration. This method features a two-dimensional array of suspended graphene plasmon nanocavities, in which the extremely high field enhancement and extraordinary compression of graphene plasmons can be realized simultaneously by combining shallow and deep cavities. This enables resonant unit cells to be read out in the spatial absorption pattern of the array at multiple spectral points, and the resulting information is then translated into the refractive index of the analytes. The proposed technique gives complementary information compared with the current nanophotonic techniques based on molecular absorption, including the ability of the refractive index measurement, the ultra-broadband measurable spectral range, and the small volume of the analyte required, thereby pushing the potential for refractometric sensing technologies into the infrared frequencies., X.X. is supported by Lee Family Scholars. S.M. acknowledges the Lee-Lucas Chair in Physics. V.G. acknowledges the Spanish Ministerio de Economia y Competitividad for financial support through the grant NANOTOPO (FIS2017-91413-EXP) and also the Ministerio de Ciencia, Innovación y Universidades through the grant MELODIA (PGC2018-095777-B-C21).

Graphene and hexagonal boron nitride (h-BN) have attracted intensive interests in very recent years because of their unique physical and chemical properties. With similar crystal structures, graphe...

Coronavirus disease 2019 (COVID‐19) has widely spread all over the world and the numbers of patients and deaths are increasing. According to the epidemiology, virology, and clinical practice, there are varying degrees of changes in patients, involving the human body structure and function and the activity and participation. Based on the World Health Organization (WHO) International Classification of Functioning, Disability and Health (ICF) and its biopsychosocial model of functioning, we use the WHO Family of International Classifications (WHO‐FICs) framework to form an expert consensus on the COVID‐19 rehabilitation program, focusing on the diagnosis and evaluation of disease and functioning, and service delivery of rehabilitation, and to establish a standard rehabilitation framework, terminology system, and evaluation and intervention systems based the WHO‐FICs.

The Raman scattering of light by molecular vibrations offers a powerful technique to ‘fingerprint’ molecules via their internal bonds and symmetries. Since Raman scattering is weak1, methods to enhance, direct and harness it are highly desirable, e.g. through the use of optical cavities2, waveguides3–6, and surface enhanced Raman scattering (SERS)7–9. While SERS offers dramatic enhancements6,15,22,2 by localizing light within vanishingly small ‘hot-spots’ in metallic nanostructures, these tiny interaction volumes are only sensitive to few molecules, yielding weak signals that are difficult to detect10 . Here, we show that SERS from 4-Aminothiophenol (4-ATP) molecules bonded to a plasmonic gap waveguide is directed into a single mode with > 99% efficiency. Although sacrificing a confinement dimension, we find > 104 times SERS enhancement across a broad spectral range enabled by the waveguide’s larger sensing volume and non-resonant mode. Remarkably, the waveguide-SERS (W-SERS) is bright enough to image Raman transport across the waveguides exposing the roles of nanofocusing11–13 and the Purcell effect14. Emulating the e-factor from laser physics15–17, the near unity Raman -factor observed exposes the SERS technique in a new light and points to alternative routes to controlling Raman scattering. The ability of W-SERS to direct Raman scattering is relevant to Raman sensors based on integrated photonics7–9 with applications in gas and bio-sensing as well as healthcare.

Structural metallic materials with excellent functional performance and lightweight features have always been the goal of material scientists’ pursuit. In this work, laminated metal composites of different thicknesses (less than 0.4 mm) composed of structural materials with great differences in deformation ability were successfully fabricated via a novel processing procedure. Ultra-high strength and excellent soft magnetic properties were combined perfectly in the ultra-thin and super-light laminated metal composite strips due to unique structural design and essential attributes of the initial materials. These results emphasize the significant potential application value of the ultra-thin laminated metal composites in the field of structural and functional integration.

methods and fabrication process

Correction to: ACS Omega 2017, 2 (7), 3640−3646. DOI: 10.1021/acsomega.7b00726

16 pags., 11 figs., Plasmonic metamaterials enable extraordinary manipulation of key constitutive properties of light at a subwavelength scale and thus have attracted significant interest. Here, we report a simple and convenient nanofabrication method for a novel meta-device by glancing deposition of gold into anodic aluminum oxide templates on glass substrates. A methodology with the assistance of ellipsometric measurements to examine the anisotropy and optical activity properties is presented. A tunable polarization conversion in both transmission and reflection is demonstrated. Specifically, giant broadband circular dichroism for reflection at visible wavelengths is experimentally realized by oblique incidence, due to the extrinsic chirality resulting from the mutual orientation of the metamaterials and the incident beam. This work paves the way for practical applications for large-area, low-cost polarization modulators, polarization imaging, displays, and bio-sensing., Beijing Municipal Commission of Education (BJJWZYJH01201910007022); National Natural Science Foundation of China (61775019).

17 pags., 10 figs., The breathing honeycomb lattice hosts a topologically non-trivial bulk phase due to the crystalline-symmetry of the system. Pseudospin-dependent edge states, which emerge at the interface between trivial and non-trivial regions, can be used for the directional propagation of energy. Using the plasmonic metasurface as an example system, we probe these states in the nearand far-field using a semi-analytical model. We provide the conditions under which directionality was observed and show that it is source position dependent. By probing with circularly-polarised magnetic dipoles out of the plane, we first characterise modes along the interface in terms of the enhancement of source emissions due to the metasurface. We then excite from the far-field with non-zero orbital angular momentum beams. The position-dependent directionality holds true for all classical wave systems with a breathing honeycomb lattice. Our results show that a metasurface in combination with a chiral two-dimensional material, could be used to guide light effectively on the nanoscale., M.P., R.V.C and P.A.H. acknowledge funding from the Leverhulme Trust. V.G. acknowledges the Spanish Ministerio de Economia y Competitividad for financial support through the grant NANOTOPO (FIS2017-91413-EXP) and also the Ministerio de Ciencia, Innovación y Universidades through the grant MELODIA (PGC2018-095777-B-C21). P.A.H. acknowledges financial support from Fundação para a Ciência e a Tecnologia and Instituto de Telecomunicações under projects UID/EEA/50008/2020 and the CEEC Individual program with reference CEECIND/03866/2017. S.A.M. acknowledges the Lee-Lucas Chair in Physics.

Rapid progress in nonlinear plasmonic metasurfaces enabled many novel optical characteristics for metasurfaces, with potential applications in frequency metrology [Zimmermann et al. Opt. Lett. 29:310 (2004)], timing characterization [Singh et al. Laser Photonics Rev. 14:1 (2020)] and quantum information [Kues et al. Nature. 546:622 (2017)]. However, the spectrum of nonlinear optical response was typically determined from the linear optical resonance. In this work, a wavelength-multiplexed nonlinear plasmon-MoS2 hybrid metasurface with suppression phenomenon was proposed, where multiple nonlinear signals could to be simultaneously processed and optionally tuned. A clear physical picture to depict the nonlinear plasmonic bound states in the continuum (BICs) was presented, from the perspective of both classical and quantum approaches. Particularly, beyond the ordinary plasmon-polariton effect, we numerically demonstrated a giant BIC-inspired second-order nonlinear susceptibility 10−5 m/V of MoS2 in the infrared band. The novelty in our study lies in the presence of a quantum oscillator that can be adopted to both suppress and enhance the nonlinear quasi BICs. This selectable nonlinear BIC-based suppression and enhancement effect can optionally block undesired modes, resulting in narrower linewidth as well as smaller quantum decay rates, which is also promising in slow-light-associated technologies.

In this work, a high-efficiency and tunable dual-frequency reflective polarization converter composed of graphene metasurface with twisting double L-shaped unit is firstly realized. Numerical results demonstrate that the device can convert a linearly polarized wave to its cross-polarized wave, and meantime it can also convert to a circularly polarized wave. Subsequently, one thickness of 500 nm SiO 2 layer sandwiched by two graphene metasurfaces with similar pattern is stacked on the top of the two-layered structure, a four-frequency efficient reflective polarization converters is realized. Above all, those working frequencies can also be dynamically tuned within a large frequency range by adjusting the Fermi energy of the graphene, without reoptimizing and refabricating the nanostructures, which paves a novel way toward developing a controllable polarization converter for mid-infrared applications.

AOP 2019, Lisbon, Portugal, 31 May - 4 June, 2019. -- http://www.aop2019.org/

Sylwester Gawinkowski opened discussion of the paper by Javier Aizpurua: How many electrons are transferred by one ultrashort pulse? If you are thinking about applications in electronics, then it seems that this number may be too small. Is simply increasing the pulse energy and therefore significantly increasing the number of such emitted electrons possible?

This paper presents a wideband tunable cross-polarization converter based on a graphene metasurface with a hollow-carved “H” array in the mid-infrared regions. The converter consists of three layers: the upper layer of the insulation dielectric layer is a periodic regular hollow-carved “H” array, and the bottom layer is a metal ground plane. Simulation is carried out by applying the frequency domain solver of the CST Microwave Studio software. The numerical simulation results show that the polarization converter transforms linear light into its cross-polarization light. The polarization conversion ratio is over 90% at 2.53 THz within the range of 34.39 to 36.92 THz, whereas the FWHM bandwidth is 3.87 THz within the range of 33.8 to 37.67 THz, about 11% of the central frequency. Thus, the cross-polarization converter can be dynamically tuned over a wide frequency range by altering the Fermi-energy of graphene, without reoptimizing and refabricating nanostructures. The operating frequency band of the proposed structure can also be tuned by changing the size of $w_1$ or $\Lambda$ while keeping the polarization conversion ratios high. Moreover, strong robustness is observed under the oblique incidence. Specifically, the polarization conversion ratios can be maintained at over 90% at angles of incidence of up to $50^\circ$ . Therefore, the proposed device has potential development and application in the manipulation of light polarization in the mid-infrared regions.

The prefabricated structure is vigorously promoted due to its obvious superiorities of high-efficiency construction rate and environment-friendly construction scheme. However, this fast-growing new structural system is still facing the threat of earthquakes, especially its beam-to-column connecting joints which are the weaker link in the entire structural system all the time. This study investigates the failure behaviour of hole-opened metallic plate connections in prefabricated energy-dissipation joints and its finite element models were provided. Parametric study was performed to obtain the influence of metallic-plate size on the bearing capacity, deformation performance, and ductility. Based on the results of numerical simulation, the failure modes of specimens were focused on weakened sections. Moreover, proposed design sizes were given, comprising that the weakened length a/L of holes is from 0.25 to 0.55 and the weakened width b/B is from 0.3 to 0.5. The suggested value of width to thickness ratio is 0.2 and the value of the gap is within 0.5 to 2 mm.

Joints and connections of assembled frame structures are weak in earthquake events, and it is difficult to repair these structures after the earthquake damage. To this end, an assembled buckling-Restrained braced frames structure with replaceable plasticity-deformation controllable steel hinge is presented. Push-over analysis and dynamic time-history analysis are carried out to obtain the seismic behaviour of the new structural such as failure sequence and decreasing ratio for interstory drift angle, and to compare with the traditional assembled frame structure. The results show that the proposed new assembled structure is better than the traditional assembled structure in bearing capacity, lateral resistance, and structural ductility. Also, it can effectively control the nonlinear response of the structure including the displacement of the floor.

8 pags., 5 figs., 1 tab., Herein we illustrate an effective protocol to boost the optical enhancing properties of gold nanostars. By coating single nanostars with a mesoporous silica layer of the appropriate size (yolk capsules), to localize them under optical microscopy, it is possible to enumerate single particles and design SERS quantitative methods with minute amounts of metallic particles., N. P.-P., L. G., and M. A. C.-D. thank the MINECO-Spain (CTM2014-58481R, CTM2017-84050R, CTQ2017-88648R and RYC-2015-19107), Xunta de Galicia (Centro Singular de Investigacion de Galicia, Acc. 2016-19 and EM2014/035), Generalitat de Cataluña (2017SGR883), URV (2017PFRURV_B2-02), URV and Banco Santander (2017EXIT-08) and the European Union (ERDF). This project has received funding from the European Union’s Horizon 2020 research and innovation program under the MarieSkłodowska-Curie grant agreement No. 713679 and from the Universitat Rovira i Virgili. X. X. acknowledges the Lee Family Scholarship.

17 pags., 10 figs., 1 tab. -- Open Access funded by Creative Commons Atribution Licence 4.0, Topological photonic systems, with their ability to host states protected against disorder and perturbation, allow us to do with photons what topological insulators do with electrons. Topological photonics can refer to electronic systems coupled with light or purely photonic setups. By shrinking these systems to the nanoscale, we can harness the enhanced sensitivity observed in nanoscale structures and combine this with the protection of the topological photonic states, allowing us to design photonic local density of states and to push towards one of the ultimate goals of modern science: the precise control of photons at the nanoscale. This is paramount for both nanotechnological applications and fundamental research in light matter problems. For purely photonic systems, we work with bosonic rather than fermionic states, so the implementation of topology in these systems requires new paradigms. Trying to face these challenges has helped in the creation of the exciting new field of topological nanophotonics, with far-reaching applications. In this article, we review milestones in topological photonics and discuss how they can be built upon at the nanoscale., M.S.R. and S.J.P. would like to acknowledge their studentships from the Centre for Doctoral Training on Theory and Simulation of Materials at Imperial College London funded by EPSRC (Grant No. EP/L015579/1). S.R.P. acknowledges funding from EPSRC. X.X. is supported by a Lee family scholarship. P.A.H. acknowledges The Gordon and Betty Moore Foundation. V.G. acknowledges the Spanish Ministerio de Economia y Competitividad for financial support through the grant NANOTOPO (No. FIS2017-91413-EXP) and also Consejo Superior de Investigaciones Científicas (INTRAMURALES No. 201750I039). V.G. acknowledges support from CSIC Research Platform on Quantum Technologies PTI-001.

9 pags. 5 figs., Plasmonic biosensors have demonstrated superior performance in detecting various biomolecules with high sensitivity through simple assays. Scaled-up, reproducible chip production with a high density of hotspots in a large area has been technically challenging, limiting the commercialization and clinical translation of these biosensors. A new fabrication method for 3D plasmonic nanostructures with a high density, large volume of hotspots and therefore inherently improved detection capabilities is developed. Specifically, Au nanoparticle-spiked Au nanopillar arrays are prepared by utilizing enhanced surface diffusion of adsorbed Au atoms on a slippery Au nanopillar arrays through a simple vacuum process. This process enables the direct formation of a high density of spherical Au nanoparticles on the 1 nm-thick dielectric coated Au nanopillar arrays without high-temperature annealing, which results in multiple plasmonic coupling, and thereby large effective volume of hotspots in 3D spaces. The plasmonic nanostructures show signal enhancements over 8.3 × 10-fold for surface-enhanced Raman spectroscopy and over 2.7 × 10-fold for plasmon-enhanced fluorescence. The 3D plasmonic chip is used to detect avian influenza-associated antibodies at 100 times higher sensitivity compared with unstructured Au substrates for plasmon-enhanced fluorescence detection. Such a simple and scalable fabrication of highly sensitive 3D plasmonic nanostructures provides new opportunities to broaden plasmon-enhanced sensing applications., This work was supported by the Fundamental Research Program (PNK 6070) of the Korean Institute of Materials Science (KIMS) and the Ministry of Trade, Industry and Energy (Grant N0002310). S.A.M. acknowledges ONR Global, the EPSRSC Reactive Plasmonics Programme (EP/M013812/1), the Lee-Lucas Chair in Physics, and the Bavarian Solar Energies Go Hybrid (SolTech) programme. X.X. was supported by Lee Family Scholars. H.I. was supported in part by National Cancer Institute of the National Institutional of Health under award number R00CA201248.

International audience; (600:[600]600) Sylwester Gawinkowski opened a general discussion of the paper by Jorge Salmon-Gamboa: Why you are using SiO 2 nanoparticles? Do they have any function or are they only the substrate to attach other active nano-particles to? You have shown that only gold nanoparticles attached to silica nanoparticles do not inuence the rate of reaction signicantly. You have also demonstrated that adding platinum decorations on the gold nanoparticles causes a strong increase in the reaction rate. The signicance of the gold nanoparticles would be more clearly shown with a simple experiment in which you have no gold nanoparticles but still have platinum decorations. Jorge Salmon-Gamboa replied: Silica nanoparticles were chosen as a nano-sized inert substrate for Au nanoparticles. This choice of substrate provides a larger surface area covered with the active Au-Pt nanoparticles, in contrast to the situation when the active particles are placed directly onto a at substrate. Aiming for applications, the SiO 2-Au-Pt nanoparticles can then in turn be attached onto a at surface, forming a solid device that can be submerged into water, avoiding the problem of water contamination by nanoparticles. The role of the Au nano-particles was investigated. Under illumination in the LSP spectral band (556-566 nm), SiO 2-Pt did not enhance the reaction rate. In contrast, under the same conditions, SiO 2-Au-Pt showed a considerably enhanced rate, proving that hot carriers were generated in Au (see Fig. 1 below). (601:[601]601) Yuri Diaz Fernandez continued the discussion: I have two questions: (1) Can you comment on the dispersity of the size distribution of metal and SiO 2 particles and how well controlled are these in your system?

9 pags., 7 figs. -- Open Access funded by Creative Commons Atribution Licence 4.0, We study a one-dimensional plasmonic system with nontrivial topology: a chain of metallic nanoparticles with alternating spacing, which in the limit of small particles is the plasmonic analogue to the Su-Schrieffer-Heeger model. Unlike prior studies we take into account long-range hopping with retardation and radiative damping, which is necessary for the scales commonly used in plasmonics experiments. This leads to a non-Hermitian Hamiltonian with frequency dependence that is notably not a perturbation of the quasistatic model. We show that the resulting band structures are significantly different, but that topological features such as quantized Zak phase and protected edge modes persist because the system has the same eigenmodes as a chirally symmetric system. We discover the existence of retardation-induced topological phase transitions, which are not predicted in the SSH model. We find parameters that lead to protected edge modes and confirm that they are highly robust under disorder, opening up the possibility of protected hotspots at topological interfaces that could have novel applications in nanophotonics.

About 70% injury of gymnasts happened during landing - an interaction between gymnast and landing mat. The most injured joint is the ankle. The current study examined the effect of mechanical properties of landing mat on ankle loading with aims to identify means of decreasing the risk of ankle injury.Gymnastic skill - salto backward stretched with 3/2 twist was captured by two high-speed camcorders and digitized by using SIMI-Motion software. A subject-specific, 14-segment rigid-body model and a mechanical landing-mat model were built using BRG.LifeMODTM. The landings were simulated with varied landing-mat mechanical properties (i.e., stiffness, dampness and friction coefficients).Real landing performance could be accurately reproduced by the model. The simulations revealed that the ankle angle was relatively sensitive to stiffness and dampness of the landing mat, the ankle loading rate increased 26% when the stiffness was increased by 30%, and the changing of dampness had notable effect on horizontal ground reaction force and foot velocity. Further, the peak joint-reaction force and joint torque were more sensitive to friction than to stiffness and dampness of landing mat. Finally, ankle muscles would dissipate about twice energy (189%) when the friction was increased by 30%.Loads to ankles during landing would increase as the stiffness and dampness of the landing mat increase. Yet, increasing friction would cause a substantial rise of the ankle internal loads. As such, the friction should be a key factor influencing the risk of injury. Unfortunately, this key factor has rarely attracted attention in practice.

We report the structural and magnetic properties of Ni2In-type (Mn0.75Cu0.25)66Ga34 alloy by using powder X-ray diffraction, DC- and AC-susceptibility, aging effect and magnetic memory effect measurements. From the results of the DC-susceptibility measurements, an irreversible temperature Tirr(0) = 109.1 ± 1.4 K and a crossover exponent Φ = 4.9 ± 0.3 are obtained, which indicate that our system favors a canonical Heisenberg spin-glass state. From the AC-susceptibility results, the shift of freezing temperature with frequency is characterized by a medium Mydosh parameter of 0.03. Furthermore, a relaxation time of the spin flip τ 0 = 1.1 × 10 − 9 s and a critical exponent z v = 7.5 are obtained by the fitting of power law. A significant aging effect and a magnetic memory effect in both zero-field-cooled and field-cooled protocols are observed. In addition, the memory effect existing in a negative T cycle but missing in a positive T cycle favors the hierarchical model in our sample. All the above observations render a cluster spin-glass behavior in (Mn0.75Cu0.25)66Ga34 alloy.

8 pags., 5 figs., Spherical colloidal superclusters, composed from sub-100 nm plasmonic nanoparticles, have been proposed to possess collective plasmonic modes imbued with large field enhancements and tunable spectral response extending from the visible to infrared regions. Here, we report the experimental verification of collective near-IR plasmonic modes inside single superclusters, with dimensions ranging from 0.77 μm up to 2 μm. Raman reporters, coated onto the nanoparticle building blocks, were used as local probes of the electric field enhancement inside the metamaterial. By performing diffraction-limited 3D Raman tomography we were able to build up the electric field intensity distribution within the superclusters. We demonstrate that plasmonic responses of superclusters vary according to their size and excitation wavelength, in accordance with theoretical predictions of their tunable optical properties. The existence of three-dimensional internal collective modes in these superclusters enables the excitation of a large number of electromagnetic hot-spots, validating these self-assembled structures as promising candidates for molecular spectroscopy., A.L. thanks the WITec doctoral prize fellowship scheme for financial support. X.X. thanks the Lee Family doctoral prize fellowship scheme for financial support. L.V. would like to acknowledge the support of the H2020-MSCA fellowship. E.C. is supported by a Marie Curie fellowship of the European Commission. V.G. acknowledges ONR Global funding (N62909-15-1-N082). J.B.E. has been funded in part by ERC starting (NanoP) and consolidator (NanoPD) grants along with an EPSRC grant EP/L02098X/1. S.A.M. acknowledges the EPSRC Reactive Plasmonics Programme (EP/MO13812/ 1) and the Lee-Lucas Chair. A.R. would like to acknowledge the Royal Society for their support (UF150542).

8 pags., 6 figs., Positioning probe molecules at electromagnetic hot spots with nanometer precision is required to achieve highly sensitive and reproducible surface-enhanced Raman spectroscopy (SERS) analysis. In this article, molecular positioning at plasmonic nanogaps is reported using a high aspect ratio (HAR) plasmonic nanopillar array with a controlled surface energy. A large-area HAR plasmonic nanopillar array is generated using a nanolithography-free simple process involving Ar plasma treatment applied to a smooth polymer surface and the subsequent evaporation of metal onto the polymer nanopillars. The surface energy can be precisely controlled through the selective removal of an adsorbed self-assembled monolayer of low surface-energy molecules prepared on the plasmonic nanopillars. This process can be used to tune the surface energy and provide a superhydrophobic surface with a water contact angle of 165.8° on the one hand or a hydrophilic surface with a water contact angle of 40.0° on the other. The highly tunable surface wettability is employed to systematically investigate the effects of the surface energy on the capillary-force-induced clustering among the HAR plasmonic nanopillars as well as on molecular concentration at the collapsed nanogaps present at the tops of the clustered nanopillars., This study was supported financially by the Fundamental Research Program (PNK 5060) of the Korean Institute of Materials Science (KIMS). Dr. S.-G. Park is grateful for support from the Basic Science Research Program of the National Research Foundation of Korea (NRF), funded by the Ministry of Science, ICT and Future Planning (Grant No. NRF-2015R1C1A01053884). X. Xiao is grateful for support from the Lee Family Scholars. A.B. and S.A.M. acknowledge the EPSRC and ONR Global

In order to meet the Ministry of Education applied technology university, promote vocational schools' public English teaching reform and achieve comprehensive development of Power Engineering majors, this paper theoretical basis of combing the different levels of teaching, try to explore and admire the traditional teaching methods combined to achieve Public English Course for Power Engineering majors Specialty implementation level teaching approach in order to improve teaching effectiveness, and promote the application of culture, vocational talents.