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- 实验方案
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Brazing, Laser, and Electron-Beam Welding of Additively Manufactured GRCop-84 Copper for Phased Array Lower Hybrid Launchers
摘要: Recent advances in selective laser melting 3-D printing technology allow additive manufacturing of lower hybrid current drive (LHCD) RF launchers from a new material, Glenn Research Copper 84 (GRCop-84), a Cr2Nb (8 at. % Cr, 4 at. % Nb) precipitation hardened alloy, in configurations unachievable by conventional machining. Cr2Nb crystals pin grain boundaries within the copper matrix resulting in high tensile strength and resistance to annealing at elevated temperatures. Brazing, laser, and electron-beam welding (EBW) techniques are explored for joining a thin-walled GRCop-84 waveguide with zero porosity and minimal internal surface roughness. GRCop-84 wets well with the silver solder, CuSil, and Cusil-ABA brazes, once the durable surface oxide is mechanically removed. GRCop-84 melt pool size and flow during EBW is reduced compared to oxygen-free copper (OFC). Pulsed laser and e-beam welding maintains the Cr2Nb precipitate size; precipitate coarsening occurs in conduction mode e-beam welding.
关键词: joining processes,fusion reactor design,magnetic confinement,Annealing,tokamaks,copper alloys,melt processing,materials processing,phased arrays,waveguide
更新于2025-09-23 15:21:01
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EXPRESS: Potentialities of a Laser-Induced Breakdown Spectroscopy Technique in the Study of Polymer Composites
摘要: A laser-induced breakdown spectroscopy (LIBS) technique was used to evaluate the filler content in particulate epoxy–copper composites. A potential application for a direct and fast measurement of the filler in composites through the LIBS results is suggested using calibrated samples. The methodology used in this work makes possible the incorporation of LIBS as a quantitative technique for the study of particle metal filled epoxy composites, providing a method to obtain a direct estimation of the filler volume fraction.
关键词: LIBS,Laser-induced breakdown spectroscopy,epoxy composites,copper,plasma
更新于2025-09-23 15:21:01
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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) - Optoelectronic Characterization of Emerging Solar Absorber Cu <sub/>3</sub> AsS <sub/>4</sub>
摘要: Enargite Cu3AsS4 is a promising absorber for thin-film solar cells but little is known about its optoelectronic properties. Here, we present photoluminescence (PL) spectroscopy, time-resolved terahertz spectroscopy (TRTS), time-resolved photoluminescence (TRPL) spectroscopy, and cyclic voltammetry (CV) measurements of enargite thin films. The results indicate promising defect characteristics with minority carrier lifetimes on the order of ns, and band alignments suggest that buffer layers besides CdS must be developed to achieve high efficiency Cu3AsS4 solar cells.
关键词: photovoltaic cells,copper compounds,thin film devices,semiconductor materials,nanocrystals
更新于2025-09-23 15:21:01
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Sputtered p-type Cu <sub/>x</sub> Zn <sub/>1-x</sub> S back contact to CdTe solar cells
摘要: As thin film cadmium telluride (CdTe) solar cells gain prominence, one particular challenge is optimizing contacts and their interfaces to transfer charge without losses in efficiency. Back contact recombination is still significant and will prevent CdTe solar technology from reaching its full potential in device efficiency, and transparent back contacts have not been developed for bifacial solar technology or multijunction solar cells. To address these challenges, this study investigates sputtered CuxZn1-xS as a p-type semi-transparent back contact material to thin film polycrystalline CdTe solar cells, at Cu concentrations x = 0.30, 0.45 and 0.60. This material is selected for its high hole conductivity (160 to 2,120 S cm-1), wide optical band gap (2.25 to 2.75 eV), and variable ionization potential (approximately 6 to 7 eV) that can be aligned to that of CdTe. We report that without device optimization, CdTe solar cells with these CuxZn1-xS back contacts perform as well as control cells with standard ZnTe:Cu back contacts. We observe no reduction in external quantum efficiency, low contact barrier heights of approximately 0.3 eV, and carrier lifetimes on par with those of baseline CdTe. These cells are relatively stable over one year in air, with VOC and efficiency of the x = 0.30 cell decreasing by only 1% and 3%, respectively. Using SEM and STEM to investigate the CuxZn1-xS?CdTe interface, we demonstrate that the CuxZn1-xS layer segregates into a bilayer of Cu-Te-S and Zn-Cd-S, and thermodynamic reaction calculations support these findings. Despite its bilayer formation, the back contact still functions well. This investigation explains some of the physical mechanisms governing the device stack, inspires future work to understand interfacial chemistry and charge transfer, and elicits optimization to achieve higher efficiency CdTe cells.
关键词: solar cell back contact design,transparent semiconductors,copper zinc sulfide,solar cell interfaces,CdTe photovoltaics
更新于2025-09-23 15:21:01
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Processing of Keyhole Depth Measurement Data during Laser Beam Micro Welding
摘要: Analysing the quality of weld seams is still a challenging task. An optical inspection of the surface is giving limited information about the shape and depth of the weld seam. An application for laser beam welding with high demands regarding the weld depth consistency is the electrical contacting of battery cells. The batteries themselves have a limited terminal or case thickness that must not be penetrated during the welding process to avoid leakage or damage to the cell. That leads to a minimum weld depth to ensure the electrical functionality, and a maximum weld depth indicated by the case thickness. In such applications, a destructive analysis is not suitable which leads to the demand for a non-destructive measurement during the process. Using a coaxial, interferometric measurement setup, the keyhole depth during the deep penetration welding is measureable. For a keyhole with a depth of a couple of millimetres, such a system is commercially available. In micro scale, however, these systems are facing several challenges such as scanning systems, small spot diameters of a few tens of micrometres and narrow keyholes. This study contains an investigation of an interferometric measurement of the keyhole depth and the suitability for laser micro welding. Therefore, the data processing of the achieved measurements is investigated, and the results are compared with the depth measurement of metallographic analysed samples. Stainless steel is used to investigate the behaviour and the stability of developed data processing strategy and the resulting depth values.
关键词: Laser welding,battery,copper,spatial power modulation,aluminium,keyhole depth measurement
更新于2025-09-23 15:21:01
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Quantum Dota??Catalyzed Photoreductive Removal of Sulfonyla??Based Protecting Groups
摘要: This communication describes the use of CuInS2/ZnS quantum dots (QDs) as photocatalysts for the reductive deprotection of aryl sulfonyl-protected phenols. For a series of aryl sulfonates with electron-withdrawing substituents, the rate of deprotection for the corresponding phenyl aryl sulfonates increases with decreasing electrochemical potential for the two electron transfers within the catalytic cycle. The rate of deprotection for a substrate that contains a carboxylic acid, a known QD-binding group, is accelerated by more than a factor of ten from that expected from the electrochemical potential for the transformation, a result that suggests that formation of metastable electron donor-acceptor complexes provides a significant kinetic advantage. This deprotection method does not perturb the common NHBoc or toluenesulfonyl protecting groups and, as demonstrated with an estrone substrate, does not perturb proximate ketones, which are generally vulnerable to many chemical reduction methods used for this class of reactions.
关键词: Copper Indium Sulfide,Photocatalysis,Phenylsulfonates,Deprotection,Quantum dots
更新于2025-09-23 15:21:01
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4-Tert-butylpyridine-assisted low-cost and soluble copper phthalocyanine as dopant-free hole transport layer for efficient Pb- and Sn-based perovskite solar cells
摘要: The preparation of suitable hole transport material (HTM) is critical to the performance and stability of perovskite solar cells (PSCs) with low-cost. Herein, a mass producible and soluble copper phthalocyanine decorated with butoxy donor groups (CuPc-OBu) was designed as HTM and prepared by a facile two-step synthetic route. To generate high quality HTM film, 4-tert-butylpyridine (tBP) was doped into CuPc-OBu to prepare the film and then removed by annealing. Such a tBP-assisted strategy resulted in the best efficiency of the PSCs with lead trihalide perovskite up to 19.0% (small-area of 0.1 cm2) and 10.1% (the active area of 8.0 cm2 for the module device). And the best efficiency of the tin-based PSCs with CuPc-OBu reached to 6.9%. More importantly, the device with CuPc-OBu as HTM revealed the remarkably enhanced stability. This work provides a new strategy to improve the film-quality of free-doping HTMs and enhance the efficiency and stability of Pb- and Sn-based PSCs with low-cost.
关键词: copper phthalocyanine,hole transport material,perovskite solar cells
更新于2025-09-23 15:21:01
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LASERAKUPUNKTUR a?? MODERNE LICHTTHERAPIE IN VERBINDUNG MIT JAHRTAUSENDE ALTER CHINESISCHER MEDIZIN; Laser acupuncture a?? modern light therapy in combination with the treasures of ancient chinese medicine;
摘要: The clinical efficacy of LLLT has been scientifically proven in many randomized controlled studies: wound healing disorders, oral mucositis, stroke, traumatic brain injury, nerve regeneration, age-related macular degeneration and much more. Mitochondrial medicine, laser acupuncture and LLLT combine the treasures of modern physical and physiological methods in a unique way for the benefit of our patients. LLLT means targeted mitochondrial medicine.
关键词: laser,auricular medicine,VAS,chinese medicine,resonance therapy,LLLT,cytochrome C oxidase,laser acupuncture,ROS,Weber meridian massage,COO,RAC,PBM,copper,MMW,NIR,mitochondria,coenzyme Q10
更新于2025-09-23 15:21:01
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[Materials Horizons: From Nature to Nanomaterials] Advances in Polymer Sciences and Technology (Select Papers from APA 2017) || Structural and Morphological Analysis of Newly Synthesized CuO@Alginate Nanocomposite with Enriched Electrical Properties
摘要: CuO@Alginate (CuO@Alg) nanocomposite has been synthesized by simple, inexpensive and highly efficient Sol-Gel method. The morphology and structural properties of synthesized nanocomposite (CuO@Alg) and pure CuO nanoparticles have been analyzed as a function of temperature. The morphological and structural properties were investigated by using TEM, SEM, EDX, and X-ray diffraction. The crystalline nature of CuO nanocomposite showed by X-ray diffraction (XRD) pattern and average crystalline size was observed approximately 18.09 nm. The effect of size quantization on morphology was also observed. Dielectric behavior of CuO and CuO@Alg has been also studied as a function of increasing frequency by LCR meter. With the increase in frequency, the dielectric constant was found to decrease and alternative current (A.C.) conductivity value was found to increase. This study was also representing a useful step towards the establishment of a structure–property relationship for CuO nanocomposite.
关键词: Nanocomposite,Copper oxide,Electrical conductivity
更新于2025-09-23 15:21:01
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Copper nanoclusters @ nitrogen-doped carbon quantum dots-based ratiometric fluorescence probe for lead (II) ions detection in porphyra
摘要: A novel ratiometric fluorescence probe was proposed for detecting lead (II) ions (Pb2+) in porphyra, the approach was based on copper nanoclusters and nitrogen-doped carbon quantum dots (CuNCs-CNQDs). In this probe, the CuNCs delivered the response signal, the fluorescence of which was enhanced by Pb2+ due to the aggregation-induced emission enhancement (AIEE) between Pb2+ and CuNCs. The CNQDs provided the self-calibration signal, whose fluorescence remained almost unchanged in coexistence with Pb2+. According to the change of fluorescence intensity ratio between the fluorophores, CuNCs–CNQDs nanohybrid was used as ratiometric probes for the sensitive detection of Pb2+ in the range of 0.010 to 2.5 mg L-1, with a detection limit of 0.0031 mg L-1. Finally, the probe was successfully applied to detect Pb2+ in porphyra with relative standard deviations (RSDs) lower than 5%. This study provides a straightforward, stable, and sensitive approach for detecting Pb2+ in porphyra.
关键词: Lead (II) ions,Ratiometric fluorescence probe,Aggregation-induced emission enhancement,Copper nanoclusters,Nitrogen-doped carbon quantum dots
更新于2025-09-23 15:21:01