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The construction technology of tower erection by segments with the cranes on the basis of the docking assembly has been applied in multiple cities and provinces in China. The docking assembly reduces the number of hoisting times, and lowers the safety hazards. However, the docking assembly which is an independent structure and made of common materials currently needs to be installed on and dismantled from the tower for each use, and each component is heavy. To address the above problems, the high-strength material non-dismantling docking assembly is studied to develop a design scheme which reduces the weight and eliminates the installation and dismantling work of docking assembly. Its successful engineering application shows that the use of high-strength materials effectively reduces the weight of the docking assembly and the docking assembly developed is safe and reliable, which greatly improves the efficiency of tower erection and reduces labor intensity. The project study results provide a reference for the design of high-strength material non-dismantling docking assembly for other types of transmission towers in the construction of power grids.

Fiber cladding surface plasmon resonance (SPR) sensors have few structures, and a clad SPR sensor based on S-type fiber is proposed in this paper. This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding. In this paper, the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment. Based on the conclusion that the smaller the core diameter is, the closer the working band of the SPR resonance is to long wavelengths, and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber, a dual channel SPR sensor with a double S-type fiber cascade was proposed. In the refractive index detection range of 1.333–1.385 refractive index units (RIU), the resonant working band of channel I is 627.66 nm–759.78 nm, with an average sensitivity of 2540.77 nm/RIU, and the resonant working band of channel II is 518.24 nm–658.2 nm, with an average sensitivity of 2691.54 nm/RIU. The processing method for the S-type fiber cladding SPR sensor is simple, effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel. The sensor is expected to be used in the fields of medical treatment and biological analysis.

To address the restriction of fiber-optic surface plasmon resonance (SPR) sensors in the field of multi-sample detection, a novel dual-channel fiber-optic SPR sensor based on the cascade of coaxial dual-waveguide D-type structure and microsphere structure is proposed in this paper. The fiber sidepolishing technique converts the coaxial dual-waveguide fiber into a D-type one, and the evanescent wave in the ring core leaks, generating a D-type sensing region; the fiber optic fused ball push technology converts the coaxial dual waveguides into microspheres, and the stimulated cladding mode evanescent wave leaks, producing the microsphere sensing region. By injecting light into the coaxial dual-waveguide middle core alone, the sensor can realize single-stage sensing in the microsphere sensing area; it can also realize dual-channel sensing in the D-type sensing area and microsphere sensing area by injecting light into the ring core. The refractive index measurement ranges for the two channels are 1.333–1.365 and 1.375–1.405, respectively, with detection sensitivities of 981.56 nm/RIU and 4138 nm/RIU. The sensor combines wavelength division multiplexing and space division multiplexing technologies, presenting a novel research concept for multi-channel fiber SPR sensors.

There are a large number of multi-dimensional different types sensors in DIoT (Distribution Internet of Things). Based on edge computing function of smart power DIoT terminals, local access and logical operations are realized. Data aggregation will reduce network traffic overhead and improve the real-time performance of edge computing. This paper proposes an asynchronous distributed aggregation layout construction algorithm based on hierarchical clustering. In this algorithm, all nodes are first aggregated according to the distance to construct a collection tree according to hierarchical clustering. And then the optimal number of groups is calculated according to the number of groups. Then the best aggregation node is selected according to the asynchronous distributed strategy. Simulation experiments show that the algorithm can quickly find a data aggregation method with minimal overhead, and improve the perception of power DIoT and edge computing efficiency.

Understanding the physical processes involved in interfacial heat transfer is critical for the interpretation of thermometric measurements and the optimization of heat dissipation in nanoelectronic devices that are based on transition metal dichalcogenide (TMD) semiconductors. We model the phononic and electronic contributions to the thermal boundary conductance (TBC) variability for the MoS$_{2}$-SiO$_{2}$ and WS$_{2}$-SiO$_{2}$ interface. A phenomenological theory to model diffuse phonon transport at disordered interfaces is introduced and yields $G$=13.5 and 12.4 MW/K/m$^{2}$ at 300 K for the MoS$_{2}$-SiO$_{2}$ and WS$_{2}$-SiO$_{2} $ interface, respectively. We compare its predictions to those of the coherent phonon model and find that the former fits the MoS$_{2}$-SiO$_{2}$ data from experiments and simulations significantly better. Our analysis suggests that heat dissipation at the TMD-SiO$_{2}$ interface is dominated by phonons scattered diffusely by the rough interface although the electronic TBC contribution can be significant even at low electron densities ($n\leq10^{12}$ cm$^{-2}$) and may explain some of the variation in the experimental TBC data from the literature. The physical insights from our study can be useful for the development of thermally aware designs in TMD-based nanoelectronics., 10 pages, 5 figures

A fiber cladding surface plasmon resonance (SPR) bending sensor is realized by the cladding of the fiber structure. By employing coating film, the sensing zone is protected and the toughness of the sensor increases. Three different sensing probes are tested, the experiment results indicate that the two parameters (wavelength sensitivity and light intensity sensitivity) sensing performances of the eccentric butt joint structures are superior to that of hetero-core structure, and the SPR bending sensor based on hetero-core structure is stable and uneasy to damage. By employing hetero-core fiber and silver film, a fiber cladding SPR bending sensor with better stabilization and sensing performance is realized. The proposed fabricating method of sensing probe with coating film provides a new approach for fiber SPR-distributed bending sensor.

Tip-enhanced fluorescence (TEF) with ultra-high detection sensitivity and spatial resolution has been a powerful characterization technique in the study of surface science and life science. Herein, a systematically theoretical investigation in the visible range had been performed to study TEF properties of a single molecule located inside a nanogap formed by Au tip and substrate. In the strong localized surface plasmon coupling effect, the contribution of nonlocal dielectric response to the fluorescence quantum yield as well as radiative and energy dissipated decay rates were calculated. It is found that the nonlocal dielectric effects become comparable to the radiative and energy dissipated decay rates with the increasing of the tip-molecule distance, as a result, the nonlocal dielectric effect significantly suppresses the fluorescence process. The huge excitation enhancement at the shorter tip-molecule distance can efficiently compensate the low quantum yield, leading to the great fluorescence enhancement. The results show that the maximum enhancement obtained from the calculations can reach as high as four orders of magnitude by optimizing the tip-molecule distance. These results are not only helpful to our understanding of the TEF mechanism but also valuable for its further applications.

Swelling behaviors of Shenmu-Fugu bituminous coal (SFBC) and Shengli lignite (SLL) in various organic solvents were investigated at temperatures ranging from 0 °C to 55 °C. The results show that tetrahydrofuran (THF) has a relatively higher swelling ratio in comparison to other solvents, suggesting that THF likely disrupts coal-coal cross-links between macromolecular network structures in coal. SLL swelled more highly than SFBC in methanol (MA), indicating that MA interacts strongly with specific sites on SLL. Swelling ratios of SFBC in carbon disulfide (CDS), recycle liquefaction solvent (RLS) and initial liquefaction solvent (ILS) are appreciably higher than those of SLL. Coal swelling increases with raising temperature within the temperature range studied (0-55 °C), especially in polar solvent.

According to the shape characteristics of large-caliber projectiles in shadow photography and the characteristics of external field environment, this paper focuses on the characteristics of external field shadow imaging and proposes a method for extracting the features of outfield shadow image of large-caliber projectiles. Based on the image preprocessing, the Bullet Tip feature points are determined by the intersection of the central axis and the edge, while the bullet tail feature extraction method based on ellipse fitting. The fitting accuracy of ellipse fitting method and upper and lower endpoint method are simulated and compared. The results show that the ellipse fitting method determining the center of the target end surface is better, with the extraction accuracy of 0.44 piexl.

Kerfless technology is a promising alternative for reducing cost and providing flexible thin crystals in silicon-based semiconductors. In this work we propose a protruded seed substrate technology to prepare flexible monocrystalline Si thin film economically. Grooved seed substrate is fabricated by using SiN x thin film as a mask for the wet-etching and thermal oxidation process. After the SiN x layer on the wedged strip is removed by hot phosphoric acid, the pre-defined structured substrate is achieved with the top of the strip serving as the seed site where there is no oxide layer. And a preferred growth of epitaxial Si on the substrate is performed by introducing an intermittent feed method for silicon source gas. The technique in this paper obviously enhances the mechanical stability of the seed structure and the growth behavior on the seed sites, compared with our previous techniques, so this technique promises to be used in the industrial fabrication of flexible Si-based devices.

In the present work, we theoretically study the electromagnetic (EM) enhancement of the Raman and fluorescence signals for a molecule placed in a nanocavity formed by a metallic tip and substrate that mimics a tip-enhanced Raman scattering (TERS) setup using three-dimensional finite element method calculations. The influence of tip size and tip-molecule distance on the EM enhancements of the incident field as well as the radiative and non-radiative decay rates of the molecule are systematically investigated. Simulation results show that the maximum EM enhancement to the incident light as provided by the localized surface plasmon resonance in the nanocavity can reach ∼285 for the configuration considered in the present work. Meanwhile, it was found that, at the classical limit, decreasing the apex radius or the tip-molecule distance can both reduce the spatial distribution (as characterized by the full width at half maximum) of the Raman enhancement in a linear fashion. Moreover, simulation results show that the nonlocal dielectric response of the tip and the substrate plays a key role to the fluorescence quantum yield of the molecule. However, it was found that the strong EM excitation enhancement is the dominating factor for the tip enhanced fluorescence (TEF) effect and stronger fluorescence enhancement has been found when increasing the apex radius or reducing the tip-molecule distance with an incident wavelength of 532 nm. The best TERS and TEF enhancements were found to be ∼[Formula: see text] and ∼[Formula: see text], respectively, with the tip-molecule distance around 1 nm.

During the growth of graphene via chemical vapor deposition, its recessive process, that is, etching, is often neglected. However, recent experimental studies showed that etching is not only able to give rise to complex morphologies that cannot be achieved by pure growth, but it also can be used to create designed patterns. In this work, we develop a kinetic Monte Carlo model based on the underlying mechanisms and growth kinetics of graphene to predict the formation of various morphologies during growth and etching. The simulation results reproduce a variety of experimentally observed morphologies of graphene domains with six-fold, four-fold and three-fold symmetries. In addition, we propose analytical relations between the gas flow rate in the experiments and the growth and etching parameters used in our simulations. We also present a phase diagram for the domain morphology from the attachment-limited regime to the diffusion-limited regime to guide the control of domain morphology. The present study not only presents a viable model to simulate the morphological evolution of graphene domain, but also provides essential guidance to control graphene pattern formation for specific applications.

A boron-lined proportional counter (BLPC) with a count rate limit close to the multi-wire proportional counter was manufactured to measure the mixed field around reactors. After measurement with a standard Am-Be neutron source (activity: 100 mCi), the results show that the operating voltage of the BLPC is 800 V, the plateau length is 100 V and the slope is 13.2%/100 V. The width and rise time of the output pulse of the BLPC are 1.26 μs and 370 ns, respectively. When the BLPC works at a count rate of 1.0×105 count/s, the pulse pile-up probability of the BLPC is 3.6%. A clear peak can be seen in the pulse height spectrum of the BLPC. and the performances illustrate that a BLPC working in pulse mode can serve as a source range detector of reactors.

In order to facilitate the broad applications of molecular recognition materials in biomedical areas, it is critical to enhance their adsorption capacity while maintaining their excellent recognition performance. In this work, we designed and synthesized well-defined peptide-imprinted mesoporous silica (PIMS) for specific recognition of an immunostimulating hexapeptide from human casein (IHHC) by using amphiphilic ionic liquid as the surfactant to anchor IHHC via a combination of one-step sol-gel method and docking oriented imprinting approach. Thereinto, theoretical calculation was employed to reveal the multiple binding interactions and dual-template configuration between amphiphilic ionic liquid and IHHC. The fabricated PIMS was characterized and an in-depth analysis of specific recognition mechanism was conducted. Results revealed that both adsorption and recognition capabilities of PIMS far exceeded that of the NIMS's. More significantly, the PIMS exhibited a superior binding capacity (60.5 mg g-1), which could increase 18.9% than the previous work. The corresponding imprinting factor and selectivity coefficient could reach up to 4.51 and 3.30, respectively. The PIMS also possessed lickety-split kinetic binding for IHHC, where the equilibrium time was only 10 min. All of these merits were due to the high surface area and the synergistic effect of multiple interactions (including hydrogen bonding, π-π stacking, ion-ion electrostatic interactions and van der Waals interactions, etc) between PIMS and IHHC in imprinted sites. The present work suggests the potential application of PIMS for large-scale and high-effective separation of IHHC, which may lead to their broad applications in drug/gene deliver, biosensors, catalyst and so on.

We present a theoretical study on the influence of the nonlocal dielectric response on surface-enhanced resonant Raman scattering (SERRS) and fluorescence (SEF) spectra of a model molecule confined in the center of a Ag nanoparticle (NP) dimer. In the simulations, the nonlocal dielectric response caused by the electron-hole pair generation in Ag NPs was computed with the d-parameter theory, and the scattering spectra of a model molecule representing the commonly used fluorescent dye rhodamine 6G (R6G) were obtained by density-matrix calculations. The influence of the separation between Ag NP dimers on the damping rate and scattering spectra with and without the nonlocal response were systematically analyzed. The results show that the nonlocal dielectric response is very sensitive to the gap distance of the NP dimers, and it undergoes much faster decay with the increase of the separation than the radiative and energy transfer rates. The Raman and fluorescence peaks as simulated with the nonlocal dielectric response are relative weaker than that without the nonlocal effect for smaller NP separations because the extra decay rates of the nonlocal effect could reduce both the population of the excited state and the interband coherence between the ground and excited states. Our result also indicates that the nonlocal effect is more prominent on the SEF process than the SERRS process.

A diffraction-limited three-dimensional (3D) direct laser writing (DLW) system based on two-photon polymerization can routinely pattern structures at the 100 nm length scale. Several schemes have been developed to improve the patterning resolution of 3D DLW but often require customized resist formulations or multi-wavelength exposures. Here, we introduce a scheme to produce suspended nano-webs with feature sizes below 10 nm in IP-Dip resist using sub-threshold exposure conditions in a commercial DLW system. The narrowest suspended lines (nano-webs) measured 7 nm in width. Larger ~20 nm nano-webs were patterned with ~80% yield at increased laser powers. In addition, closely spaced nano-gaps with a center-to-center distance of 33 nm were produced by patterning vertically displaced suspended lines followed by metal deposition and liftoff. We provide hypotheses and present preliminary results for a mechanism involving the initiation of a percolative path and a strain-induced narrowing in the nano-web formation. Our approach allows selective features to be patterned with dimensions comparable to the sub-10 nm patterning capability of electron-beam lithography (EBL).

Using density functional tight-binding method, we studied the mechanical properties, deformation and failure of armchair (AC) and zigzag (ZZ) phosphorene nanotubes (PNTs) with monovacancies and divacancies subjected to uniaxial tensile strain. We found that divacancies in AC PNTs and monovacancies in ZZ PNTs possess the lowest vacancy formation energy, which decreases with the tube diameter in AC PNTs and increases in ZZ PNTs. The Young's modulus is reduced, while the radial and thickness Poisson's ratios are increased by hosted vacancies. In defective AC PNTs, deformation involves fracture of the intra-pucker bonds and formation of the new inter-pucker bonds at a critical strain, and the most stretched bonds around the vacancy rupture first, triggering a sequence of the structural transformations terminated by the ultimate failure. The critical strain of AC PNTs is reduced significantly by hosted vacancies, whereas their effect on the critical stress is relatively weaker. Defective ZZ PNTs fail in a brittle-like manner once the most stretched bonds around a vacancy rupture, and vacancies are able to significantly reduce the failure strain but only moderately reduce the failure stress of ZZ PNTs. The understandings revealed here on the mechanical properties and the deformation and failure mechanisms of PNTs provide useful guidelines for their design and fabrication as building blocks in nanodevices.

We have collected an up-to-date sample of 123 superluminal sources (84 quasars, 27 BL Lac objects and 12 galaxies) and calculated the apparent velocities (βapp) for 224 components in the sources with the Λ-CDM model. We checked the relationships between their proper motions, redshifts, βapp and 5 GHz flux densities. Our analysis shows that the radio emission is strongly boosted by the Doppler effect. The superluminal motion and the relativistic beaming boosting effect are, to some extent, the same in active galactic nuclei.