- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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One-step preparation of single-layered graphene quantum dots for the detection of Fe3+
摘要： Single-layer graphene quantum dots are highly desirable while their facile and controllable preparations remain challenging. Herein, single-layered graphene quantum dots (sl-GQDs) were developed via a facile one-step hydrothermal synthesis, with citric acid and β-cyclodextrin (CD) as starting materials. The sl-GQDs decorated with CD molecules emit green fluorescence with a quantum yield of 5.34%, and exhibit a good response exclusively to ferric ions for their structural oxygenous groups. The linear range of the proposed sensor for ferric ions was found in a wide concentration range of 0-85 μM. The detection limit is about 0.26 μM. The sl-GQDs based sensing platform also demonstrates its feasibility in real water sample analysis with recoveries of 93.8%-101.5%.
关键词： One-step preparation,β-cyclodextrin,Fluorescence sensing,Single-layered graphene quantum dots,Ferric ion
更新于2025-09-19 17:13:59
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Enzymatic Preparation of Plasmonic-Fluorescent Quantum Dot-Gold Hybrid Nanoprobes for Sensitive Detection of Glucose and Alkaline Phosphatase and Dual-Modality Cell Imaging
摘要： Herein, we develop a route to prepare bifunctional plasmonic-fluorescent quantum dot-gold (QD-Au) hybrid nanoprobes by use of enzymatic reactions. Two bio-enzymes, glucose oxidase (GOx) and alkaline phosphatase (ALP) were chosen for the enzymatic preparation of core-satellite or core-shell type CdSe/ZnS@Au hybrid nanostructures. The enzymatic products, H2O2 and L-Ascorbic acid, of the two enzymes were exploited as mild reducing agents for controlled Au deposition on QD surfaces. The polymer multilayers by layer-by-layer assembly were used to adjust the separation between QD core and plasmonic Au, which can effectively reduce the quenching effect of the Au on QDs. The as-prepared QD@Au hybrid nanostructures are excellent dual-modality imaging nanoprobes, and can be used for fluorescence and dark-field scattering dual-imaging of MCF-7 cells. More importantly, the two enzymatic reaction systems can be explored for sensitive and selective detection of glucose and alkaline phosphatase, respectively, by monitoring the fluorescence spectra change of QD@Au hybrid nanoparticles, which is very useful for the glucose- and ALP-related disease diagnosis.
关键词： Biosensing,Fluorescence,Cell imaging,Enzymatic preparation,Plasmonic
更新于2025-09-19 17:13:59
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Deterministic Controlled Remote State Preparation of Real-Parameter Multi-Qubit States via Maximal Slice States
摘要： By exploiting three-qubit entangled states and appropriate measurement basis, we propose efficient protocols for deterministic controlled remote state preparation of arbitrary real-parameter multi-qubit states, in which the maximal slice states are used as quantum channel. The successful probability of our schemes can reach up to 100% by using multi-qubit mutually orthogonal measurement basis without the introduction of auxiliary particles. Based on the implementation schemes for preparing arbitrary two- and three-qubit states with real parameters, we have derived the controlled remote state preparation protocols for arbitrary real-parameter multi-qubit states.
关键词： Real-parameter multi-qubit states,Successful probability,Controlled remote state preparation,Maximal slice states
更新于2025-09-19 17:13:59
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Bidirectional controlled remote state preparation in three-dimensional system
摘要： We present a novel scheme for bidirectional controlled remote state preparation (BCRSP) in a three-dimensional system with a six-qutrit entangled state as the quantum channel. In this scheme, two distant parties, Alice and Bob, are not only senders but also receivers. Alice wants to remotely prepare a single-qutrit equatorial state at Bob’s site, while at the same time, Bob wishes to help Alice by remotely preparing another single-qutrit equatorial state. It is shown that, only if the two senders and the controller collaborate with each other, the BCRSP can be completed successfully.
关键词： Bidirectional controlled remote state preparation,six-qutrit entangled state,single-qutrit projective measurement,three-dimensional system
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) - Interstitial Light Trapping and Optical Confinement in Multijunction Solar Cells
摘要： Attack traceability and attribution are two of the main tasks of IT forensics. To support this, IT forensics is not limited to investigate data after the attack has taken place. Already before the attack, an optimal environment for a subsequent investigation has to be created. While this is primarily focused on ordinary logging, we propose to set both degree and characteristics of logging, based on geolocation. Thus, for conspicuous locations, more knowledge is gathered and stored in advance (georeputation). Next to this, due to the fact that the distribution of IP addresses is not static, additional information is stored to, e.g., determine the Internet service provider, which was responsible for the IP at the time the crime was committed. This additional data also contains geoinformation that can be used later to reconstruct attack routes and to identify and analyze distributed attacks. For these purposes, however, the IP localization mechanisms, i.e., the underlying method for geolocation, must be very accurate. Therefore, next to highlighting, the bene?ts of including geobased information and providing our architecture in order to do so, this publication also investigates accuracy and reliability of geoinformation and provides its own geolocation architecture and a corresponding prototype, including an evaluation.
关键词： geolocation,preincident preparation,Attribution,IT forensics,georeputation
更新于2025-09-19 17:13:59
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Morphology-selective preparation and formation mechanism of few-layer graphene on Cu substrate by liquid-phase pulsed laser ablation
摘要： This paper presented a morphology-selective preparation and formation mechanism of few-layer graphene (FLG) on a Cu substrate by pulsed laser ablation in liquid. It is a simple and controllable route to grow FLG directly on the surface of a copper foil at ambient temperature and normal pressure, which does not need other precursor materials. FLG with 3–10 layers of thickness and continuous hundreds of micrometers in lateral size is obtained. The morphology and structure of FLG were investigated by using a Raman spectrometer, scanning electron microscope, high-resolution transmission electron microscope, and atomic force microscope. The formation mechanism of FLG and the role of the plasma-produced carbon species are put forward based on the interaction between the laser, material, and substrate. Our finding, the direct deposition of FLG on the Cu substrate by pulsed laser ablation in liquid, will open a door to apply this green route to the production of FLG with controlled morphology.
关键词： formation mechanism,Cu substrate,morphology-selective preparation,few-layer graphene,liquid-phase pulsed laser ablation
更新于2025-09-16 10:30:52
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Synthesis of Temperature and Light Sensitive Copolymers with Controlled Aggregation during Phase Transitions
摘要： Two thermosensitive copolymers of acrylates (PMP/PEP) and a thermo/light sensitive copolymer of acrylate with acrylamide (PMABz) are synthesized via a ring-opening reaction and subsequent radical polymerization using a facile one-pot method. The lower critical solution temperature (LCST) of PMP and PEP shows a dependence on the content of the structural unit and can be easily tuned to 18–35 °C by mercaptoethanol-mediated control of the molecular weight. The isomerization of PMABz can be reversibly induced by alternating irradiation at 365 nm to produce the cis form and at 254 nm to produce the trans form. The LCST of cis-PMABz (40.3 °C) is significantly higher than that of trans-PMABz (37.8 °C) because of its higher hydrophilicity. Furthermore, the particle size of aggregated PMABz can be controlled from 665 nm (for the cis form) to 996 nm (for the trans form) during the heating run. After quenching the PMABz solution, PMABz particles have repeating patterns, such as leaf veins or hollow containers, indicating their potential applicability.
关键词： preparation,photosensitive,thermosensitivity,aggregation,particle,polymers
更新于2025-09-12 10:27:22
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Thermal joining of thermoplastics to metals: Surface preparation of steel based on laser radiation and tungsten inert gas arc process
摘要： Laser-based joining is a potential key manufacturing process for realizing metal plastic hybrids. Therefore, surface preparation is essential to achieve a mechanical form fit. A new approach for surface preparation is based on a tungsten inert gas (TIG) arc process with anodic polarity. This TIG structure was characterized compared to fiber laser manufactured structures in cw and pw mode. The comparison of different preparations was based on pure ultimate tensile strength tests on spot joints. Finally, a transfer to overlap joints was successfully carried out and characterized by tensile shear tests using fiber reinforced plastics.
关键词： laser joining,surface preparation,laser welding,TIG welding,structured steel,metal-plastic-hybrid joints,dissimilar materials,lightweight design
更新于2025-09-12 10:27:22
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Mechanoperovskites for Photovoltaic Applications: Preparation, Characterization, and Device Fabrication
摘要： Hybrid organic?inorganic metal halide perovskites (MHPs) have emerged as excellent absorber materials for next generation solar cells owing to their simple solution-processed synthesis and high efficiency. This breakthrough in photovoltaics along with an accompanying impact in light-emitting applications prompted a renaissance of interest in the broad family of MHPs. Notably, the optoelectronic properties and the photovoltaic parameters of MHPs are highly sensitive to the adopted synthetic strategy. The preparation of MHPs has commonly relied on solution-based methods requiring elevated temperatures for homogeneity of reaction mixtures. While the solution-based approach is relatively versatile, it faces challenges such as limitations in compositional engineering of MHPs or their long-term storage among others. Therefore, there is a continuous great challenge to develop efficient synthetic strategies affording various high-quality MHP materials for numerous technological optoelectronic applications.
关键词： Preparation,Characterization,Device Fabrication,Photovoltaic Applications,Mechanoperovskites
更新于2025-09-12 10:27:22
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Unusually Dispersed AgI Quantum Dots For Efficient HTL-free CH3NH3PbI3 Photovoltaics
摘要： The utilization of quantum dots (QDs) to improve the performance of perovskite solar cells (PSCs) is attracting much attention due to their unique optical and electronic properties. Most of QDs have to be prepared in advance and then incorporated into the perovskite hosts, which could not ensure the maintenance of their QD characteristics. In this work, we intelligently developed an in-situ preparation strategy to disperse AgI QDs homogeneously in perovskite host for MAPbI3:AgI(QDs) cross blended layer directly on ITO via a common and convenient spin-coating process. We combine transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS) and Raman techniques to demonstrate the cross blended MAPbI3:AgI (QDs) structure in the final perovskite devices. Furthermore, a series of simply inverted ITO/MAPbI3:AgI(QDs)/PCBM/Ag devices have been designed and fabricated. The photovoltaic performance of these solar cells show significantly improved short-circuit current density (Jsc) and a champion power conversion efficiency (PCE) of 16.41% even without a hole transport layer (HTL). The current technique induced the crystal growth toward high quality perovskite films with homogeneous structure, good crystallinity, less grain boundaries and defects, increased optical path length and uniform thickness for better solar cell performance. Besides, the impact of the current strategy also lies in a accommodation effect of the hole collection at the ITO side induced by AgI QDs, which modifies the Fermi level of perovskite films, leading to significantly decreased level difference in Fermi level/work function between the perovskite layer and ITO substrates by UPS analysis. More importantly, the charge carrier dynamics of such novel MAPbI3:AgI (QDs) structures were also scrutinized by transient photovoltage (TSPV) analysis.
关键词： in-situ preparation,AgI,quantum dots,MAPbI3:AgI,cross blended structure
更新于2025-09-12 10:27:22