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- 实验方案
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Scalable hollow nanoneedle array using stepper lithography for parallel intracellular delivery
摘要： Intracellular delivery with a nanoneedle is a versatile method of injecting various types of materials into a single cell. A single hollow needle limits the throughput of cellular delivery. This study aims to develop an array of hollow nanoneedles suitable for massively parallel delivery and mass production. The fabrication of hollow nanoneedle structures by stepper lithography looks promising, but a method for the fabrication has remained unclear. We patterned the tips of nanoneedles by i-line stepper lithography and fabricated a hollow nanoneedle array. We used silicon and silicon-on-insulator wafers and established a process for controlling needle diameter, height, and pitch. Needle tips were produced on the front side and introduction channels were formed on the backside. A fluorescent DNA solution was transported by electrokinetic ejection through a fabricated nanoneedle array.
关键词： i-line Lithography,Electrokinetic Forces,Large-scale Production,Intracellular Delivery,Hollow Needle Array
更新于2025-09-23 15:21:01
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Modulation of localized surface plasmon resonances of a silver nanoparticle array upon the presence of MoS2 coatings or underlying thin films
摘要： There has been recently a growing interest in studying light-matter coupling using supported metallic nanostructures arranged into periodic arrays. The influence on the layer thickness of two-dimensional materials such as molybdenum disulfide MoS2 on the plasmonic behaviour of these arrays has become of great relevance due to the favorable bonding between S (sulfide atom) and metal atoms such as gold and silver as well as the variation of optical transition of MoS2 depending on the atomic thickness of the film. In this work, we have numerically studied the change in absorption spectra of an ordered array of silver nanoparticles AgNPs when attached to glass as well as to glass coated with different layers of MoS2. This arrangement was compared to an AgNPs attached to glass and post coated with MoS2 films of increasing thickness. It was shown that an overcoating of four MoS2 layers results in an increased plasmonic sensitivity compared to uncoated glass/AgNPs interface. Replacing the glass substrate by glass coated with MoS2 of different thickness and with added AgNPs shows a significant to the red shift with increasing MoS2 layers. This band is due to strong excitation-plasmon coupling of the silver lattice with MoS2 layers. Important is the fact that the electrical field is strongly enhanced beneath the MoS2/AgNPs barrier. One also observes a significant enhancement of the sensitivity. Hence, the design of more sensitive AgNPs/MoS2 based-plasmonic biosensors could be reached. Indeed, we show that AgNPs coating with few layers of MoS2 leads to approximately a 210.26% higher sensitivity.
关键词： Sensitivity,MoS2,Silver nanoparticle array,BioSensors,Localized surface plasmon resonance
更新于2025-09-23 15:21:01
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[IEEE 2019 9th International Electric Drives Production Conference (EDPC) - Esslingen, Germany (2019.12.3-2019.12.4)] 2019 9th International Electric Drives Production Conference (EDPC) - Evaluation of Soft Magnetic Ferrosilicon FeSi 6.5 for Laser Beam Melting
摘要： Planar or cylindrical phased arrays are two candidate antennas for future polarimetric weather radar. These two candidate antennas have distinctly different attributes when used to make quantitative measurements of the polarimetric properties of precipitation. Of critical concern is meeting the required polarimetric performance for all directions of the electronically steered beam. The copolar and cross-polar radiation patterns and polarimetric parameter estimation performances of these two phased array antennas are studied and compared with that obtained using a dual-polarized parabolic reflector antenna. Results obtained from simulation show that the planar polarimetric phased array radar has unacceptable polarimetric parameter biases that require beam to beam correction, whereas biases obtained with the cylindrical polarimetric phased array radar are much lower and comparable to that obtained using the parabolic reflector antenna.
关键词： radiation patterns,phased array radar,cylindrical array,Antenna,polarimetry,planar array,remote sensing,weather measurement
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Environmental and Economic Considerations for PV Module End-of-Life Management
摘要： This paper suggests a real-valued sparse representation method using a unitary transformation that can convert complex-valued manifold matrices from uniform circular array into real ones. Because of this transformation, the computational complexity is modi?ed. Simulation results con?rmed the effectiveness of the proposed method with a circular array radar.
关键词： array signal processing,Angle of arrival (AOA),uniform circular array (UCA)
更新于2025-09-23 15:19:57
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[IEEE 2019 International Applied Computational Electromagnetics Society Symposium - China (ACES) - Nanjing, China (2019.8.8-2019.8.11)] 2019 International Applied Computational Electromagnetics Society Symposium - China (ACES) - A Band-Stop Plasmonic Filter Based on Spoof Surface Plasmon Polaritons
摘要： Direction of arrival (DOA) estimation from the perspective of sparse signal representation has attracted tremendous attention in past years, where the underlying spatial sparsity reconstruction problem is linked to the compressive sensing (CS) framework. Although this is an area with ongoing intensive research and new methods and results are reported regularly, it is time to have a review about the basic approaches and methods for CS-based DOA estimation, in particular for the underdetermined case. We start from the basic time-domain CS-based formulation for narrowband arrays and then move to the case for recently developed methods for sparse arrays based on the co-array concept. After introducing two specifically designed structures (the two-level nested array and the co-prime array) for optimizing the virtual sensors corresponding to the difference co-array, this CS-based DOA estimation approach is extended to the wideband case by employing the group sparsity concept, where a much larger physical aperture can be achieved by allowing a larger unit inter-element spacing and therefore leading to further improved performance. Finally, a specifically designed uniform linear array structure with associated CS-based underdetermined DOA estimation is presented to exploit the difference co-array concept in the spatio-spectral domain, leading to a significant increase in degrees of freedom. Representative simulation results for typical narrowband and wideband scenarios are provided to demonstrate their performance.
关键词： Compressive sensing,difference co-array,direction of arrival estimation,sparse array structures,underdetermined
更新于2025-09-23 15:19:57
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[IEEE 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Rome, Italy (2019.6.17-2019.6.20)] 2019 PhotonIcs & Electromagnetics Research Symposium - Spring (PIERS-Spring) - Non-reciprocity and Doppler Effect Control by Using Time-varying Metamaterials and Metasurfaces
摘要： With single-input single-output (SISO) SAR systems, employing a single transmitter and receiver beam, there exists a high resolution, wide swath contradiction. However, by using multiple receiver beams and employing array processing techniques, this contradiction can be overcome, allowing greater ?exibility and a wider range of application requirements to be met. In this paper the use of single-input multiple-output (SIMO) SAR systems for overcoming this contradiction is of interest, and a novel beamformer is proposed for processing in the cross-range direction. In order to fully describe the system, the array manifold vector is utilized, which is a key concept in the design of the beamformer. In particular, this beamformer is a superresolution beamformer capable of forming wide nulls using subspace based approaches and allows the suppression of ambiguities in multiple sets of received undersampled SAR data in the cross-range direction and reconstruction of the Doppler spectrum to form a single unambiguous set of SAR data. Compared to the existing reconstruction algorithm, only a single weighting vector is required for a block of ambiguous Doppler frequencies compared to a weight vector required for each ambiguous Doppler frequency. The capabilities of the proposed beamformer are shown to give an improved performance in ambiguity suppression via computer simulation studies in a representative maritime environment.
关键词： array processing,Single-input multiple-output (SIMO) synthetic aperture radar (SAR),array manifold vector
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Industrial Production and Field Evaluation of Transparent Electrodynamic Screen (EDS) Film for Water-Free Cleaning of Solar Collectors
摘要： Since their introduction, field programmable gate arrays (FPGAs) have grown in capacity by more than a factor of 10 000 and in performance by a factor of 100. Cost and energy per operation have both decreased by more than a factor of 1000. These advances have been fueled by process technology scaling, but the FPGA story is much more complex than simple technology scaling. Quantitative effects of Moore’s Law have driven qualitative changes in FPGA architecture, applications and tools. As a consequence, FPGAs have passed through several distinct phases of development. These phases, termed ‘‘Ages’’ in this paper, are The Age of Invention, The Age of Expansion and The Age of Accumulation. This paper summarizes each and discusses their driving pressures and fundamental characteristics. The paper concludes with a vision of the upcoming Age of FPGAs.
关键词： commercialization,programmable logic,Moore’s Law,Application-specific integrated circuit (ASIC),economies of scale,field-programmable gate array (FPGA),industrial economics
更新于2025-09-23 15:19:57
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Direct dynamic evidence of charge separation in a dyea??sensitized solar cell under operando conditions by Raman spectroscopy
摘要： Interfaces play an important role in enhancing the energy conversion performance of dye-sensitized solar cells (DSCs). The interface effects have been studied by many techniques, but almost all studies only performed on a portion of DSC, rather than on a complete solar cell. Hence, monitoring the interface evolution of a DSC is still very challenging. Here, in situ/operando resonance Raman (RR) spectroscopic analyses were carried out to monitor the dynamic observations of the photovoltaic conversion process from a DSC. We observed the creation of new species (i.e., polyiodide and iodine aggregates) in the photosensitization process. We also successfully identified molecular-scale dynamic evidence that the bands from the C═C of 2,2’-bipyridyl (bpy), the S═C═N of NCS ligand and photochemical products show reasonably strong intensity and frequency changes, which clearly demonstrates that they are important pathways of charge separation. Furthermore, RR spectroscopy also be applicable to quickly evaluate the performance of DSCs.
关键词： dye-sensitized solar cell,semiconductor,TiO2 nanotube array,Raman spectroscopy,charge transfer
更新于2025-09-23 15:19:57
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A mechanically bendable and conformally attachable polymer membrane microlaser array enabled by digital interference lithography
摘要： The progressive miniaturization and thinning of photonic devices would enable the realization of multi-functional photonic integrated circuits and expand the application frontier to novel fields including wearable and disposable electronics. Herein, we have demonstrated a mechanically bendable and conformally attachable polymer membrane microcavity laser array using digital interference lithography. The developed lithography system could distribute a number of subwavelength grating pixels with both high efficiency (1k pixels per second) and excellent versatility (ease of control in the pixel size, spacing, and grating periodicity) as the microcavity laser array, in which a pair of subwavelength gratings constitutes a distributed Bragg resonator microcavity via coherent interference, furnishes a vertically emitting microcavity laser array for convenient light coupling and utilization. The microlaser array polymer membrane presented a total thickness of only 30 μm with excellent performance stability and reliability against long time operation and harsh environmental conditions, which could be further reversibly stretched, repeatedly bendable and conformally attached onto rounded or irregular surfaces or biological tissues with no degradation in single-mode or low-threshold characteristics, paving a way for on-chip optical functionalization toward wearable electronics and outdoor environmental monitoring applications.
关键词： polymer membrane,digital interference lithography,microlaser array,mechanically bendable,conformally attachable
更新于2025-09-23 15:19:57
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Novel reconfiguration approach to reduce line losses of the photovoltaic array under various shading conditions
摘要： This paper presents a novel fixed reconfiguration scheme to reduce partial shading conditions in the Photovoltaic (PV) array. The proposed approach is based on Skyscraper (SS) technique, which implies that the physical location of the PV modules in the array is arranged using Skyscraper fashion so that it distributes the shading impacts across the array in order to increase energy yields. Various kinds of partial shading conditions have been taken into account to examine the effects on the proposed approach in 6×6 array. Further, the performance of the proposed arrangement is compared with the other existing array interconnections such as ”series-parallel (SP), total-cross-tied (TCT), bridge-link (BL), honey-comb (HC) and Arrow-SuDoKu (AS)” by obtaining the several parameters like ”global maximum power point (GMPP), the voltage at GMPP, fill-factor, shading losses, efficiency, and possible local peaks (PLP)”. In addition to this, a simple calculation is performed to evaluate the wiring losses for the proposed skyscraper arrangement. Lastly, the outcome of this paper demonstrates that the suggested skyscraper scheme reduces the loss of shading and increases the power production relative to the other array interconnections. Also, in comparison with the Arrow SuDoKu scheme, the proposed scheme is impacted by the minimum wiring loss.
关键词： Photovoltaic Modelling,PV array Interconnections,Static fixed reconfiguration
更新于2025-09-23 15:19:57