- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Ferromagnetic Behavior and Electronic Characterization of ZnO Nanoparticles
摘要： In this work, Al-doped ZnO nanoparticles encapsulated with amorphous SiO2 were prepared by the wet chemical method. The obtained precursor was annealed and the nanoparticle sizes were controlled by adjusting the annealing temperature. These nanomaterials showed ferromagnetic behavior, even though the ZnO bulk crystal was diamagnetic. The results of electrical conductivity and XANES suggested that ferromagnetism of the Al-doped nanoparticles was results of carrier transport and oxygen vacancies. The Al-doped ZnO nanoparticles are extremely interesting from the perspective of solid state physics. [DOI: 10.1380/ejssnt.2018.406]
关键词： Nano-particles, quantum dots, and supra-molecules,Magnetic, structural, and other properties of nanostructures,Zinc oxide,Luminescence,Near edge extended X-ray absorption fine structure (NEXAFS)
更新于2025-09-04 15:30:14
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Influência do Strain e da Intera??o Spin-órbita em um Ponto Quantico Cilíndrico
摘要： In this work study how the strain and spin-orbit Rashba interaction type affect the energy levels of the conduction band in a cylindrical quantum dot, using the 2x2 method k●p. The results show that the spin-orbit interaction strongly influences the energy levels of lifting the degeneracy even in zero magnetic field, while the strain compressing the levels enhance the Rashba interaction effects. In this context, the intraband optic absorption becomes a useful tool to study the effects of spin-orbit interaction and the strain on the electron energy levels.
关键词： k●p method,Conduction Band,Quantum dots,Strain,Spin-orbit Rashba interaction
更新于2025-09-04 15:30:14
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CQDS preluded carbon-incorporated 3D burger-like hybrid ZnO enhanced visible-light-driven photocatalytic activity and mechanism implication
摘要： Environmentally friendly photodegradation of refractory pollutants utilizing semiconductor photocatalysis evolution exhibits satisfactory efficiency and low energy consumption, but some of its unbefitting band position largely limits practical applications. The controllable band structure tuning via coupling low-dimensional materials with enormous potential in semiconductor photocatalysis, notably attractive carbon quantum dots (CQDs) induced for a better utilization of low-energy photoexcitation of promising inherent optical properties and photocatalytic performance on organic pollutant degradation. Here, a CQDs modified ZnO hybrid materials was synthesized and the CQDs preluded carbon-incorporated burger-like ZnO nanoparticles clusters were presented thus demonstrated a specific doping-effect. The dispersity improved by loading halloysite nanotube (HNTs) for efficiently photocatalytic activity enhancement. Furthermore, the band structure, excitation and photocatalytic reactive oxygen species (ROS) generation were detected to reveal the photochemical properties and plausible mechanism of CQDs hybrid nanomaterials system. It is observed that the superoxide radical (O2?), and singlet oxygen (1O2) are the principal ROS agents under UV–vis excitations. This work not only displays a CQDs modified system of expanding photo-response range to visible light but also throws a way for quantum elemental incorporated on the influence of band-tuning for semiconductor- dominated photocatalysts.
关键词： Carbon-incorporated,Tetracycline,Photocatalysis,Carbon quantum dots,ZnO
更新于2025-09-04 15:30:14
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Carbon Nitride Dots: A Selective Bioimaging Nanomaterial
摘要： In contrast to the recent immense attention in carbon nitride quantum dots (CNQDs) as a heteroatom-doped carbon quantum dot (CQD), their biomedical applications have not thoroughly investigated. The targeted cancer therapy is a prominently researched area in biomedical field. Here, the ability of CNQDs as a selective bioimaging nanomaterial was investigated to assist the targeted cancer therapy. CNQDs were first synthesized using four different precursor sets, involving urea derivatives and the characteristics were compared to select the best candid material for bioapplications. Characterization techniques such as UV-vis, luminescence X-ray photoelectron spectroscopy, nuclear magnetic resonance spectroscopy and transmission electron microscopy were used. These CNQDs were analyzed in in vitro studies of bioimaging and labeling using pediatric glioma cells (SJGBM2) for possible selective biolabeling and nano-distribution inside the cell membrane. The in vitro cellular studies were conducted under long-wavelength emission without the interference of blue autofluorescence. Thus, excitation-dependent emission of CNQDs was proved to be advantageous. Importantly, CNQDs selectively entered SJGBM2 tumor cells while it did not disperse in to normal human embryonic kidney cells (HEK293). The distribution studies in the cell cytoplasm indicated that CNQDs disperse into lysosomes within approximately 6 h after the incubation. The CNQDs exhibited great potential as a possible nanomaterial in selective bioimaging and drug-delivery for targeted cancer therapy.
关键词： Pediatric glioma cells,Long-wavelength emission,Urea derivatives,Carbon nitride Quantum dots,Fluorescence,Selective bioimaging
更新于2025-09-04 15:30:14
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A TiO2/g-C3N4/CdS Nanocomposite-Based Photoelectrochemical Biosensor for Ultrasensitive Evaluation of T4 Polynucleotide Kinase Activity
摘要： Herein, an efficient photoelectrochemical (PEC) platform was constructed by a co-sensitization strategy with a cascade energy level arrangement for the ultrasensitive evaluation of T4 polynucleotide kinase (T4 PNK). Based on CdSe quantum dots (QDs) with an extremely narrow bandgap, this co-sensitization strategy offered a highly efficient sensitizer with a matching band-edge level of a ternary TiO2/g-C3N4/CdS nanocomposite. In this protocol, the ternary nanocomposite was first prepared to serve as the matrix to construct the PEC sensing platform. On the other hand, a well-designed hairpin DNA1 probe with 5’-hydroxyl termini was specifically phosphorylated by T4 PNK which would be selectively cleaved with lambda exonuclease (λ-Exo) outputting 3’-thiol end ssDNA2. After tagged with CdSe QDs, ssDNA2 was captured by the complementary capture DNA3 on the electrode surface. As a result, CdSe QDs were in close contact with the ternary nanocomposite matrix, leading to an enhanced photocurrent response. Therefore, this proposed PEC platform displayed an analytical performance with a wide linear range from 0.0001 to 0.02 U mL-1 and a low detection limit down to 6.9 × 10-5 U mL-1. Moreover, this ternary nanocomposite-based platform exhibited excellent selectivity, good reproducibility, and remarkable storage stability, which shows the great potential for the T4 PNK detection and inhibitor screening.
关键词： CdSe quantum dots,T4 polynucleotide kinase,ternary nanocomposite,co-sensitization strategy,photoelectrochemical biosensor
更新于2025-09-04 15:30:14
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Binary atomic silicon logic
摘要： It has been proposed that miniature circuitry will ultimately be crafted from single atoms. Despite many advances in the study of atoms and molecules on surfaces using scanning probe microscopes, challenges with patterning and limited thermal structural stability have remained. Here we demonstrate rudimentary circuit elements through the patterning of dangling bonds on a hydrogen-terminated silicon surface. Dangling bonds sequester electrons both spatially and energetically in the bulk bandgap, circumventing short-circuiting by the substrate. We deploy paired dangling bonds occupied by one moveable electron to form a binary electronic building block. Inspired by earlier quantum dot-based approaches, binary information is encoded in the electron position, allowing demonstration of a binary wire and an OR gate.
关键词： binary wire,dangling bonds,OR gate,quantum dots,binary atomic silicon logic
更新于2025-09-04 15:30:14