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).

/pdf/a-review-of-electrode-materials-for-electrochemical-2cok5em0bo.pdf

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

Microstructure of high temperature–pressure treated nitrogen-doped Czochralski silicon

硅异质结(SHJ)太阳电池由于具有本征非晶硅/掺杂非晶硅的双层膜结构, 表现出了优异的钝化特性. 在本文中, 我们在加热光照条件下研究了SHJ太阳电池的少子寿命变化情况, 发现其会有明显提升. 通过分析饱和电流密度(J 0)的数值变化, 将此现象归因于SHJ太阳电池的表面钝化质量提高. 基于以上实验结果, 利用指数函数拟合模型可以提取出不同温度下光致增强的速率, 并利用阿伦尼乌斯拟合, 得到光致增强的激活能为0.47 eV, 这说明钝化质量提高与非晶硅层中的氢扩散有关. 此外, 稳定性测试结果显示SHJ太阳电池的增强效果可以维持至少1000小时. 本研究结果对于理解SHJ太阳电池的光致增强机理及其实际应用十分有意义, 有助于进一步推进全球光伏产业的发展. 

/pdf/light-soaking-induced-performance-enhancement-in-a-si-h-c-si-30pj7fvd.pdf

Light soaking-induced performance enhancement in a-Si:H/c-Si heterojunction solar cells

Germanium-doped silicon is studied actively for application in microelectronics, in particular, as an improvement of the radiation hardness of the silicon substrate can be achieved. However, the impact of the introduced germanium on the electrical stability and properties of the silicon material and devices is also of special concern. In this contribution we report the results of a study on the effects of low temperature thermal anneals relevant for backend processing, on the electrical characteristics of p-on-n diodes fabricated on Czochralski-grown (CZ) Ge-doped-Si with two different germanium concentrations (1.10(19) cm(-3) and 1.2.10(20) cm(-3)), as well as on control CZ Si wafers without Ge doping. The results show good diode yield and uniformity, with little differences between the electrical characteristics of the fabricated diodes on the different substrates. However, interestingly for device applications, a significantly lower thermal donor generation (by one order of magnitude) is found for the case of the higher Gedoped material subjected to 450 degrees C thermal anneals.

Diode Characteristics and Thermal Donor Formation in Germanium-Doped Silicon Substrates

Fairly pure ultraviolet electroluminescence from p-Si-based SiOx/ZnO/SiOx double-barrier device

Interactions of iron atoms with dislocations in n-type Czochralski silicon have been studied by combining deep level transient spectroscopy (DLTS) and electron beam induced current (EBIC). The EBIC results indicate that dislocations facilitate the aggregation of iron atoms. The DLTS reveals three levels K1 (E c—0.17 eV), K2 (E c—0.35 eV) and K3 (E c—0.48 eV). The amplitudes of K2 and K3 peaks exhibit extended localized states. The origin of levels K2 and K3 is attributed to iron clusters around dislocations, and the existence of iron clusters in the vicinity of dislocations is further proved.

https://iopscience.iop.org/article/10.35848/1882-0786/abdcd3/pdf

Deren Yang

Papers

Microstructure of high temperature–pressure treated nitrogen-doped Czochralski silicon

Light soaking-induced performance enhancement in a-Si:H/c-Si heterojunction solar cells

Diode Characteristics and Thermal Donor Formation in Germanium-Doped Silicon Substrates

Fairly pure ultraviolet electroluminescence from p-Si-based SiOx/ZnO/SiOx double-barrier device

Electrical property of iron-related defects in n-type dislocated Czochralski silicon crystal used for solar cells