- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Laser-induced forward transfer of viscoplastic?fluids
摘要： Laser-induced forward transfer (LIFT) is a nozzle-free printing technology that can be used for two- and three-dimensional printing. In LIFT, a laser pulse creates an impulse inside a thin film of material that results in the formation of a liquid jet. We experimentally study LIFT of viscoplastic materials by visualizing the process of jetting with high-speed imaging. The shape of the jet depends on the laser energy, focal height, surface tension and material rheology. We theoretically identify the characteristic jetting velocity and how it depends on the control parameters, and define non-dimensional groups to classify the regimes of jetting. Based on the results, we propose the optimal conditions for printing with LIFT technology.
关键词： complex fluids,interfacial flows (free surface),non-Newtonian flows
更新于2025-09-19 17:13:59
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Plasmonics of Au/Polymer Core/Shell Nanocomposites for Thermoresponsive Hybrid Metasurfaces
摘要： We investigate the temperature-dependent optical response of ordered lattices of non-interacting gold-core/poly(N-isopropylacrylamide)-shell nanoparticles (NPs), a system with proven photothermal and sensing capabilities. For the first time on this system, we exploited in situ Spectroscopic Ellipsometry (SE) to determine the complex, temperature-dependent optical properties of the lattice, a key piece of information which, however, is often overlooked. In doing so, we take full advantage of large-scale colloidal self-assembly, which makes NP lattices accessible to conventional SE. A quantitative interpretation of the SE data is obtained through an effective model based on the actual characteristics of the NPs and their dielectric environment. The model allows to estimate temperature-dependent morphological parameters, such as the distance between the gold cores and the substrate, also yielding the complex permittivity of the plasmonic NP lattice. Thus, by combining the high sensitivity of SE with proper modelling, we provide a comprehensive characterization of thermoresponsive NP lattices. The approach proposed here is instrumental to the analysis and design of functional hybrid metasurfaces with plasmonic functionalities, including particle-to-film coupled systems.
关键词： spectroscopic ellipsometry,PNIPAM,localized surface plasmon resonance,complex permittivity,core-shell particles
更新于2025-09-19 17:13:59
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Optical and structural-chemistry of SnS nanocrystals prepared by thermal decomposition of bis(N-di-isopropyl-N-octyl dithiocarbamato)tin(II) complex for promising materials in solar cell applications
摘要： Mixed ligand precursor complex bis(N-di-isopropyl-N-octyl dithiocarbamato)tin(II) complex was synthesized from its respective dithiocarbamate ligands, characterized and thermalized through thermogravimetric analysis to yield tin sulfide (SnS) nanocrystals. The thermal decomposition pattern was recorded as a function of the required temperature for the formation of the SnS nanocrystals at 360 °C. The SnS nanocrystals were characterized using optical, vibrational, structural and morphological analyses instruments. The obtained orthorhombic phase SnS nanocrystals showed indirect and direct optical energy band gaps close to the 1.5 eV of the bulk SnS.
关键词： SnS nanocrystals,Thermal decomposition pattern,Mixed ligand precursor complex,Orthorhombic phase,Thermogravimetric analysis
更新于2025-09-19 17:13:59
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Bioinspired Simultaneous Changes in Fluorescence Color, Brightness, and Shape of Hydrogels Enabled by AIEgens
摘要： Development of stimuli-responsive materials with complex practical functions is significant for achieving bioinspired artificial intelligence. It is challenging to fabricate stimuli-responsive hydrogels showing simultaneous changes in fluorescence color, brightness, and shape in response to a single stimulus. Herein, a bilayer hydrogel strategy is designed by utilizing an aggregation-induced emission luminogen, tetra-(4-pyridylphenyl)ethylene (TPE-4Py), to fabricate hydrogels with the above capabilities. Bilayer hydrogel actuators with the ionomer of poly(acrylamide-r-sodium 4-styrenesulfonate) (PAS) as a matrix of both active and passive layers and TPE-4Py as the core function element in the active layer are prepared. At acidic pH, the protonation of TPE-4Py leads to fluorescence color and brightness changes of the actuators and the electrostatic interactions between the protonated TPE-4Py and benzenesulfonate groups of the PAS chains in the active layer cause the actuators to deform. The proposed TPE-4Py/PAS-based bilayer hydrogel actuators with such responsiveness to stimulus provide insights in the design of intelligent systems and are highly attractive material candidates in the fields of 3D/4D printing, soft robots, and smart wearable devices.
关键词： stimuli-responsive hydrogels,complex shape,simultaneous changes,fluorescence,aggregation-induced emission luminogens
更新于2025-09-19 17:13:59
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Effect of fluoro-substituted acceptor-based ancillary ligands on the photocurrent and photovoltage in dye-sensitized solar cells
摘要： Herein, we report four novel heteroleptic ruthenium (II) complexes, namely SD-7 to SD-10, containing fluoro- and trifluoro- methyl antennas as substituents on the ancillary ligands for dye-sensitized solar cells, and were compared to the benchmark dye N719. Photosensitizers (dyes) SD-7 to SD-10 were synthesized according to a typical one-pot three-step procedure with the corresponding ancillary ligands (LS-7 to LS-10). All the dyes were characterized by ATR-FTIR, 1H NMR and mass spectrometry. Furthermore, the photophysical, electrochemical and photovoltaic performances were compared with N719. The band gaps, ground and excited state oxidation potentials were measured. The photovoltaic performance of the dyes showed that SD-7 with five fluorine atoms and SD-8 with eCF3 at the –ortho position of the phenyl moiety outperformed the benchmark dye N719 with the efficiencies of 8.03% and 8.17%, respectively, with current density of 19.57 and 19.46 mA?cm?2, respectively, and open-circuit voltages of 0.65 V and 0.69 V, respectively, under optimized conditions. The fabricated solar devices at lab-scale showed a systematic trend of decreasing JSC when the fluoro-substituted dyes were sensitized on TiO2: SD-7 (with five –F) > SD-8 (with one eCF3 at ortho position) > SD-9 (with one eCF3 at para position) > SD-10 (with two eCF3, one at ortho and one at para position). This can be attributed to the greater number of fluorine atoms directly attached to sp2 hybridized carbon atoms, which greatly enhanced the dipole moment and intimate electronic coupling of SD-7 with TiO2 nanoparticles leading to better photocurrent density.
关键词： Fluoro-based dyes,Acceptor-based ancillary ligand,Photovoltaic performance,Dye-sensitized solar cells,Ruthenium complex
更新于2025-09-19 17:13:59
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Degradation of Human Serum Albumin by Infrared Free Electron Laser Enhanced by Inclusion of a Salen-Type Schiff Base Zn (II) Complex
摘要： A salen‐type Schiff base Zn(II) complex included in human serum albumin (HSA) protein was examined by UV‐Vis, circular dichroism (CD), and fluorescence (PL) spectra. The formation of the composite material was also estimated by a GOLD program of ligand–protein docking simulation. A composite cast film of HSA and Zn(II) complex was prepared, and the effects of the docking of the metal complex on the degradation of protein molecules by mid‐infrared free electron laser (IR‐FEL) were investigated. The optimum wavelengths of IR‐FEL irradiation to be used were based on experimental FT‐IR spectra and vibrational analysis. Using TD‐DFT results with 6‐31G(d,p) and B3LYP, the IR spectrum of Zn(II) complex could be reasonably assigned. The respective wavelengths were 1652 cm?1 (HSA amide I), 1537 cm?1 (HSA amide II), and 1622 cm?1 (Zn(II) complex C=N). Degradation of HSA based on FT‐IR microscope (IRM) analysis and protein secondary structure analysis program (IR‐SSE) revealed that the composite material was degraded more than pure HSA or Zn(II) complex; the inclusion of Zn(II) complex enhanced destabilization of folding of HSA.
关键词： IR‐FEL,TD‐DFT,human serum albumin,Schiff base,fluorescence,Zn(II) complex
更新于2025-09-19 17:13:59
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[IEEE 2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE) - Moscow, Russia (2020.3.12-2020.3.14)] 2020 International Youth Conference on Radio Electronics, Electrical and Power Engineering (REEPE) - Simulation of Solar Energy Photovoltaic Conversion
摘要： Cardiovascular diseases are projected to remain the single leading cause of death globally. Timely diagnosis and treatment of these diseases are crucial to prevent death and dangerous complications. One of the important tools in early diagnosis of arrhythmias is analysis of electrocardiograms (ECGs) obtained from ambulatory long-term recordings. The design of novel patch-type ECG recorders has increased the accessibility of these long-term recordings. In many applications, it is furthermore an advantage for these devices that the recorded ECGs can be analyzed automatically in real time. The purpose of this study was therefore to design a novel algorithm for automatic heart beat detection, and embed the algorithm in the CE marked ePatch heart monitor. The algorithm is based on a novel cascade of computationally ef?cient ?lters, optimized adaptive thresholding, and a re?ned search back mechanism. The design and optimization of the algorithm was performed on two different databases: The MIT-BIH arrhythmia database (Se = 99.90%, P+ = 99.87) and a private ePatch training database (Se = 99.88%, P+ = 99.37%). The of?ine validation was conducted on the European ST-T database (Se = 99.84%, P+ = 99.71%). Finally, a double-blinded validation of the embedded algorithm was conducted on a private ePatch validation database (Se = 99.91%, P+ = 99.79%). The algorithm was thus validated with high clinical performance on more than 300 ECG records from 189 different subjects with a high number of different abnormal beat morphologies. This demonstrates the strengths of the algorithm, and the potential for this embedded algorithm to improve the possibilities of early diagnosis and treatment of cardiovascular diseases.
关键词： ePatch ECG recorder,real-time ECG analysis,Automatic QRS complex detection,embedded ECG analysis,patch-type ECG recorder
更新于2025-09-19 17:13:59
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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) - An Economic and Environmental Assessment of Residential Rooftop Photovoltaics with Second Life Batteries in the US
摘要： Extreme learning machine (ELM) is emerged as an effective, fast, and simple solution for real-valued classification problems. Various variants of ELM were recently proposed to enhance the performance of ELM. Circular complex-valued extreme learning machine (CC-ELM), a variant of ELM, exploits the capabilities of complex-valued neuron to achieve better performance. Another variant of ELM, weighted ELM (WELM) handles the class imbalance problem by minimizing a weighted least squares error along with regularization. In this paper, a regularized weighted CC-ELM (RWCC-ELM) is proposed, which incorporates the strength of both CC-ELM and WELM. Proposed RWCC-ELM is evaluated using imbalanced data sets taken from Keel repository. RWCC-ELM outperforms CC-ELM and WELM for most of the evaluated data sets.
关键词： extreme learning machine,Real valued classification,complex valued neural network,class imbalance problem,regularization,weighted least squares error
更新于2025-09-19 17:13:59
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Oxygen in Complex Oxide Thin Films Grown by Pulsed Laser Deposition: a Perspective
摘要： For thin film synthesis of complex oxides, one of the most important issues has always been how to oxidise the material. For a technique like pulsed laser deposition, a key benefit is the relatively high oxygen background pressure one can operate at, and therefor oxidation should be relatively straightforward. However, understanding the microscopic oxidation mechanisms turns out to be rather difficult. In this perspective, we give a brief overview of the sources of oxidation for complex oxide thin films grown by pulsed laser deposition. While it is clear what these sources are, their role in the kinetics of the formation of the crystal structure and oxygen stoichiometry is not fully understood.
关键词： High Tc superconductors,Oxidation,Thin films,Complex oxides,Pulsed laser deposition
更新于2025-09-19 17:13:59
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Towards white light emission from a hybrid thin film of a self-assembled ternary samarium( <scp>iii</scp> ) complex
摘要： A new samarium complex [Sm(hfaa)3(Py-Im)] (ML) was synthesized by utilizing hexafluoroacetylacetone (hfaa) and 2-(2-pyridyl)benzimidazole (Py-Im) as coordinating ligands. A single crystal X-ray analysis shows that in the solid-state the complex dimerizes through intermolecular hydrogen-bonding with N–H···O (2.127 ?) and N–H···F (2.576 ?) interactions. The complex in the solid-state displayed highly monochromatic brilliant red emission with Commission International de I’Eclairage (CIE) color coordinates of 0.6532; 0.3336, with a remarkably long luminescence lifetime (≈ 204.47 ± 4.043 μs) and a high intrinsic quantum yield (≈ 6.60 %). Furthermore, the complex in different organic media displayed color tunability from orange (CIE; 0.6071; 0.3568) to violet (CIE; 0.3634; 0.2144) with from 105.50 ± 0.143 – 14.27 ± 0.033 μs. Hybrid and flexible thin films obtained by doping different concentrations (1%, 2%, 4% and 6%) of the complex into the poly(urethane) (PU) polymer matrix also exhibited color tunability from violet (CIE; 0.3380; 0.2162) to light orange (CIE; 0.5666; 0.3408). White light emission from a 1% doped thin film of the complex was realized by changing the excitation wavelength. The new material could be a potential candidate for the fabrication of full-color display devices and for solid-state lighting (SSL) applications.
关键词： luminescence,white light emission,color tunability,samarium complex,solid-state lighting
更新于2025-09-19 17:13:59