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NaOH分解 1

抑制杂质 1

杂质行为 1

硅外延片 1

硅片 1

碳捕集、利用与封存；碳源杂质；腐蚀环境特点；腐蚀影响因素；超临界CO2 1

绝缘体上硅 1

缺陷控制 1

表面质量 1

钨冶金 1

锗硅 1

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Effects of ionic impurities on crystallization of cobalamin

Baoli SHAO, Hui CHEN, Shuang WANG, Haijun WANG, Shenmin XU,

《化学科学与工程前沿（英文）》 2010年第4卷第1期页码 70-74 doi: 10.1007/s11705-009-0293-3

摘要： In this paper, the influence of two typical ionic impurities (Na and Mg) is investigated with the focused beam reflectance measurement (FBRM) technique. In this system, the on-line FBRM is used as a tool for monitoring the crystallization process of cobalamin by measuring the chord length distribution of particles and the particle counts. It is noted that impurity Mg has a more significant effect than Na in crystal growth of the whole crystallization process. From the microscopic observation of crystals, Mg has an obvious effect on the crystal habit, while Na has little effect. In addition, the crystal habit changes can be monitored by particle vision measurement (PVM). Understanding these effects is helpful to aid optimization and improve process control.

关键词： cobalamin impurity particle addition technique

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钨矿物原料NaOH分解过程中抑制杂质的研究

李洪桂,李运姣,孙培梅,刘茂盛

《中国工程科学》 2000年第2卷第3期页码 59-61

摘要：

从理论上较全面地研究了钨矿物原料在NaOH分解过程中直接用白钨矿及其分解产物Ca(OH)₂作为抑制剂，抑制磷、砷、硅等杂质浸出的可能性及生成物的形态。进而通过实验证明在有白钨矿存在的条件下，分解所得的粗Na₂WO₄溶液中砷、硅的含量均比经典法低一个数量级，接近经典法净化以后的水平。

关键词：钨冶金 NaOH分解抑制杂质

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硅及硅基半导体材料中杂质缺陷和表面的研究

屠海令

《中国工程科学》 2000年第2卷第1期页码 7-17

摘要：

随着超大规模集成电路设计线宽向深亚微米级（＜0.5μm）和亚四分之一微米级（＜0.25μm）发展，对半导体硅片及其它硅基材料的质量要求越来越高，研究上述材料中各种杂质的行为，控制缺陷类型及数量，提高晶体完整性，降低表面污染和采用缺陷工程的方法改善材料质量显得尤为重要。文章阐述了深亚微米级和亚四分之一微米级集成电路用大直径硅材料中铁、铜金属和氧、氢、氮非金属杂质元素的行为，点缺陷及其衍生缺陷的本质与控制方法，硅片表面形貌、表面污染与检测方法的研究热点。同时还介绍了外延硅、锗硅及绝缘体上硅（SOI）等硅基材料的特性、制备及工艺技术发展趋势，展望了跨世纪期间硅及硅基材料产业发展的技术经济前景。

关键词：硅片硅外延片锗硅绝缘体上硅杂质行为缺陷控制表面质量

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Perspective of mixed matrix membranes for carbon capture

Shinji Kanehashi, Colin A. Scholes

《化学科学与工程前沿（英文）》 2020年第14卷第3期页码 460-469 doi: 10.1007/s11705-019-1881-5

摘要： Polymeric membrane-based gas separation has found wide applications in industry, such as carbon capture, hydrogen recovery, natural gas sweetening, as well as oxygen enrichment. Commercial gas separation membranes are required to have high gas permeability and selectivity, while being cost-effective to process. Mixed matrix membranes (MMMs) have a composite structure that consists of polymers and fillers, therefore featuring the advantages of both materials. Much effort has been made to improve the gas separation performance of MMMs as well as general membrane properties, such as mechanical strength and thermal stability. This perspective describes potential use of MMMs for carbon capture applications, explores their limitations in fabrication and methods to overcome them, and addresses their performance under industry gas conditions.

关键词： membranes polymeric mixed matrix impurities

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Detailed analysis of PCBs and PCDD/Fs impurities in a dielectric oil sample (ASKAREL Nr 1740) from an

Jun HUANG, Yamei HUI, Toru MATSUMURA, Gang YU, Shubo DENG, Makoto YAMAUCHI, Changmin WU, Norimasa YAMAZAKI

《环境科学与工程前沿（英文）》 2014年第8卷第2期页码 195-204 doi: 10.1007/s11783-013-0527-y

摘要： Homolog and congener profiles of polychlorinated biphenyls (PCBs), polychlorinated dibenzo- - dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in commercial PCBs formulations are useful information for the source appointment of PCBs contamination as well as the risk assessment caused by potential exposure. Dielectric oil (ASKAREL Nr 1740) in an imported transformer found in China was sampled and analyzed by isotope dilution technology using high resolution gas chromatography-high resolution mass spectrometry (HRGC/HRMS). The detailed homolog and congener profiles of PCBs obtained were compared with those of known Aroclor formulations. High similarity in the homolog profile between the oil sample and Aroclor 1260 was found, with the hexachlorinated and heptachlorinated biphenyls accounting for more than 80.2% of the total PCBs concentration. Severn indicator PCBs contribute about 30%, while 12 PCB congeners (i.e., #153, #143, #168, #180, #149, #165, #138, #170, #190, #187, #174, #181) account for more than 50% of the total PCB concentrations. Total concentration of PCDDs, PCDFs and dioxin-like PCBs (DL-PCBs) was found to be 740 ng TEQ/g, of which 620 ng TEQ/g came from DL-PCBs. The contribution of PCDDs to the total TEQ was neglectable. The concentration of PCDFs homologs follows the order of OCDF>HxCDFs>HpCDFs>PeCDFs>TeCDFs, which is in consistence with the previous study on Aroclor 1260. Three DL-PCBs congeners (i.e., #118, #156, #157) accounted for 77% of the total concentration of DL-PCBs, also they contribute 72% in the TEQ caused by DL-PCBs.

关键词： profiles of polychlorinated biphenyls (PCBs) polychlorinated dibenzo-p-dioxins (PCDDs) polychlorinated dibenzofurans (PCDFs) Askarel transformer insulating fluid

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Laser enhanced gettering of silicon substrates

Daniel CHEN,Matthew EDWARDS,Stuart WENHAM,Malcolm ABBOTT,Brett HALLAM

《能源前沿（英文）》 2017年第11卷第1期页码 23-31 doi: 10.1007/s11708-016-0441-7

摘要： One challenge to the use of lightly-doped, high efficiency emitters on multicrystalline silicon wafers is the poor gettering efficiency of the diffusion processes used to fabricate them. With the photovoltaic industry highly reliant on heavily doped phosphorus diffusions as a source of gettering, the transition to selective emitter structures would require new alternative methods of impurity extraction. In this paper, a novel laser based method for gettering is investigated for its impact on commercially available silicon wafers used in the manufacturing of solar cells. Direct comparisons between laser enhanced gettering (LasEG) and lightly-doped emitter diffusion gettering demonstrate a 45% absolute improvement in bulk minority carrier lifetime when using the laser process. Although grain boundaries can be effective gettering sites in multicrystalline wafers, laser processing can substantially improve the performance of both grain boundary sites and intra-grain regions. This improvement is correlated with a factor of 6 further decrease in interstitial iron concentrations. The removal of such impurities from multicrystalline wafers using the laser process can result in intra-grain enhancements in implied open-circuit voltage of up to 40 mV. In instances where specific dopant profiles are required for a diffusion on one surface of a solar cell, and the diffusion process does not enable effective gettering, LasEG may enable improved gettering during the diffusion process.

关键词： gettering multicystaline silicon impurities laser doping

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Impact of thermal processes on multi-crystalline silicon

Moonyong KIM,Phillip HAMER,Hongzhao LI,David PAYNE,Stuart WENHAM,Malcolm ABBOTT,Brett HALLAM

《能源前沿（英文）》 2017年第11卷第1期页码 32-41 doi: 10.1007/s11708-016-0427-5

摘要： Fabrication of modern multi-crystalline silicon solar cells involves multiple processes that are thermally intensive. These include emitter diffusion, thermal oxidation and firing of the metal contacts. This paper illustrates the variation and potential effects upon recombination in the wafers due to these thermal processes. The use of light emitter diffusions more compatible with selective emitter designs had a more detrimental effect on the bulk lifetime of the silicon than that of heavier diffusions compatible with a homogenous emitter design and screen-printed contacts. This was primarily due to a reduced effectiveness of gettering for the light emitter. This reduction in lifetime could be mitigated through the use of a dedicated gettering process applied before emitter diffusion. Thermal oxidations could greatly improve surface passivation in the intra-grain regions, with the higher temperatures yielding the highest quality surface passivation. However, the higher temperatures also led to an increase in bulk recombination either due to a reduced effectiveness of gettering, or due to the presence of a thicker oxide layer, which may interrupt hydrogen passivation. The effects of fast firing were separated into thermal effects and hydrogenation effects. While hydrogen can passivate defects hence improving the performance, thermal effects during fast firing can dissolve precipitating impurities such as iron or de-getter impurities hence lower the performance, leading to a poisoning of the intra-grain regions.

关键词： gettering grain boundaries hydrogen impurities oxidation passivation solar cell

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Corrosion behavior of metallic alloys in molten chloride salts for thermal energy storage in concentrated solar power plants: A review

Wenjin Ding, Alexander Bonk, Thomas Bauer

《化学科学与工程前沿（英文）》 2018年第12卷第3期页码 564-576 doi: 10.1007/s11705-018-1720-0

摘要：

Recently, more and more attention is paid on applications of molten chlorides in concentrated solar power (CSP) plants as high-temperature thermal energy storage (TES) and heat transfer fluid (HTF) materials due to their high thermal stability limits and low prices, compared to the commercial TES/HTF materials in CSP-nitrate salt mixtures. A higher TES/HTF operating temperature leads to higher efficiency of thermal to electrical energy conversion of the power block in CSP, however causes additional challenges, particularly increased corrosiveness of metallic alloys used as containers and structural materials. Thus, it is essential to study corrosion behaviors and mechanisms of metallic alloys in molten chlorides at operating temperatures (500–800 °C) for realizing the commercial application of molten chlorides in CSP. The results of studies on hot corrosion of metallic alloys in molten chlorides are reviewed to understand their corrosion behaviors and mechanisms under various conditions (e.g., temperature, atmosphere). Emphasis has also been given on salt purification to reduce corrosive impurities in molten chlorides and development of electrochemical techniques to in-situ monitor corrosive impurities in molten chlorides, in order to efficiently control corrosion rates of metallic alloys in molten chlorides to meet the requirements of industrial applications.

关键词： corrosion mechanisms impurities metallic corrosion salt purification electrochemical techniques

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碳捕集利用与封存中的金属腐蚀问题研究：进展与挑战

向勇 ,原玉 ,周佩 ,刘广胜 ,吕伟 ,李明星 ,张春霞 ,周庆军 ,赵雪会 ,闫伟

《中国工程科学》 2023年第25卷第3期页码 197-208 doi: 10.15302/J-SSCAE-2023.07.026

摘要：

深入研究碳捕集、利用与封存（CCUS）技术中的金属腐蚀问题产生的机理和影响，对有效应对和解决捕集、运输、利用与封存系统中存在的材料腐蚀失效问题至关重要，为此，本文对CCUS技术存在的金属腐蚀问题研究进展及挑战进行了综述。本文基于CCUS技术各系统腐蚀环境新颖、腐蚀行为特殊、认知程度有限、防护手段相对匮乏等情况，结合CCUS各系统中的腐蚀环境特点，分析了可能存在的金属腐蚀类型及其主要影响因素，并对其带来的挑战进行了梳理，得出了以下主要结论：对于有机胺捕集系统，吸收剂降解机理及降解产物对腐蚀过程的影响较为复杂，部分降解产物对金属腐蚀有抑制作用；密相CO2输送管道的内腐蚀问题不容忽视，控制水分含量是控制该腐蚀问题的关键；CO2驱油利用与封存系统井筒管材在超高CO2分压、碳源杂质、高矿化度地层水、微生物和应力等多因素的长周期耦合作用下，出现腐蚀失效导致CO2泄露的风险很高。最后，本文对未来需迫切开展的研究方向进行了展望，包括不同碳源杂质对各子系统的腐蚀影响研究、长期封存条件下井筒区域材料降解规律研究以及CCUS系统腐蚀防护技术研究等。

关键词：碳捕集、利用与封存；碳源杂质；腐蚀环境特点；腐蚀影响因素；超临界CO2

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标题作者时间类型操作

Effects of ionic impurities on crystallization of cobalamin

Baoli SHAO, Hui CHEN, Shuang WANG, Haijun WANG, Shenmin XU,

期刊论文

钨矿物原料NaOH分解过程中抑制杂质的研究

李洪桂,李运姣,孙培梅,刘茂盛

期刊论文

硅及硅基半导体材料中杂质缺陷和表面的研究

屠海令

期刊论文