There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

In this critical review, metal oxides-based materials for electrochemical supercapacitor (ES) electrodes are reviewed in detail together with a brief review of carbon materials and conducting polymers. Their advantages, disadvantages, and performance in ES electrodes are discussed through extensive analysis of the literature, and new trends in material development are also reviewed. Two important future research directions are indicated and summarized, based on results published in the literature: the development of composite and nanostructured ES materials to overcome the major challenge posed by the low energy density of ES (476 references).

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A review of electrode materials for electrochemical supercapacitors

1. Introduction 20642. Synthesis of Magnetic Nanoparticles 20662.1. Classical Synthesis by Coprecipitation 20662.2. Reactions in Constrained Environments 20682.3. Hydrothermal and High-TemperatureReactions20692.4. Sol-Gel Reactions 20702.5. Polyol Methods 20712.6. Flow Injection Syntheses 20712.7. Electrochemical Methods 20712.8. Aerosol/Vapor Methods 20712.9. Sonolysis 20723. Stabilization of Magnetic Particles 20723.1. Monomeric Stabilizers 20723.1.1. Carboxylates 20733.1.2. Phosphates 20733.2. Inorganic Materials 20733.2.1. Silica 20733.2.2. Gold 20743.3. Polymer Stabilizers 20743.3.1. Dextran 20743.3.2. Polyethylene Glycol (PEG) 20753.3.3. Polyvinyl Alcohol (PVA) 20753.3.4. Alginate 20753.3.5. Chitosan 20753.3.6. Other Polymers 20753.4. Other Strategies for Stabilization 20764. Methods of Vectorization of the Particles 20765. Structural and Physicochemical Characterization 20785.1. Size, Polydispersity, Shape, and SurfaceCharacterization20795.2. Structure of Ferro- or FerrimagneticNanoparticles20805.2.1. Ferro- and Ferrimagnetic Nanoparticles 20805.3. Use of Nanoparticles as Contrast Agents forMRI20825.3.1. High Anisotropy Model 20845.3.2. Small Crystal and Low Anisotropy EnergyLimit20855.3.3. Practical Interests of Magnetic NuclearRelaxation for the Characterization ofSuperparamagnetic Colloid20855.3.4. Relaxation of Agglomerated Systems 20856. Applications 20866.1. MRI: Cellular Labeling, Molecular Imaging(Inﬂammation, Apoptose, etc.)20866.2.

Magnetic Iron Oxide Nanoparticles: Synthesis, Stabilization, Vectorization, Physicochemical Characterizations, and Biological Applications

[Liu, Chang; Li, Feng; Ma, Lai-Peng; Cheng, Hui-Ming] Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China.;Cheng, HM (reprint author), Chinese Acad Sci, Inst Met Res, Shenyang Natl Lab Mat Sci, 72 Wenhua Rd, Shenyang 110016, Peoples R China;cheng@imr.ac.cn

Advanced Materials for Energy Storage

Thin silicon nano-wires (SiNWs) with a diameter of ∼10–20 nm were fabricated by a simple thermal evaporation of silicon wafer at 1523 K. The gold produced by an electrochemical method was covered on the wafer surface as catalyst. It was found that the SiNWs are amorphous and its Raman peak shifted down maybe due to the effect of laser heating and quantum confinement. Finally, a temperature gradient growth model is suggested to explain the growth direction of SiNWs.

Silicon nano-wires fabricated by thermal evaporation of silicon wafer

In this paper, through the investigation of the effect of rapid thermal processing (RTP) at different temperatures on oxygen precipitation in Czochralski (CZ) silicon wafers subjected to two-step (low?high) anneal and one-step high-temperature anneal, the enhancement role played by vacancies in oxygen precipitation occurring at low temperature and high temperature have been revealed. For the two-step anneal, the RTP-introduced vacancies significantly facilitate the formation of oxygen precipitate nuclei during the low-temperature anneal and, therefore, enhance oxygen precipitation during the subsequent high-temperature anneal. Regarding the one-step high-temperature anneal, the RTP-induced vacancies that later combine with oxygen atoms to become the O2V species significantly enhance the early stage oxygen precipitation in terms of the precipitation rate, however, the RTP-induced vacancies do not increase the amount of precipitated oxygen atoms in the CZ silicon wafer subjected to a prolonged high-temperature anneal. Due to the fact that for the CZ wafer with prior RTP the one-step high-temperature anneal produces much lower density bulk microdefects than the two-step (low?high) anneal, it is believed that the low-temperature anneal is a must for the 'magic denuded zone' process.

Effects of rapid thermal processing on oxygen precipitation in Czochralski silicon wafer

Large-scale synthesis of water-soluble nanowires as versatile templates for nanotubes

Infrared spectra of silicon nanowires

Strongly enhanced red electroluminescence (EL) was realized at room temperature (RT) from a polycrystalline diamond film (PDF)∕n−-Si heterojunction fabricated by direct chemical vapor deposition of PDF on silicon substrate. The red EL peaks featuring fairly narrow linewidth (∼12nm) were obtained when the device was under sufficient reverse bias with the positive voltage applied on the silicon substrate. Cathodoluminescence spectra measured from 77K to RT suggested that the enhanced red EL peaks originated from the neutral vacancy induced intrinsic defects of the PDF rather than the Si-related centers. The carrier transport mechanism of the PDF∕n−-Si heterojunction was elucidated based on the proposed energy band diagram of the PDF∕n−-Si heterojunction.

Deren Yang

Papers

Silicon nano-wires fabricated by thermal evaporation of silicon wafer

Effects of rapid thermal processing on oxygen precipitation in Czochralski silicon wafer

Large-scale synthesis of water-soluble nanowires as versatile templates for nanotubes

Infrared spectra of silicon nanowires

Enhanced red electroluminescence from a polycrystalline diamond film/Si heterojunction structure