On the pulmonary toxicity of oxygen. 5. Electronic structure and the paramagnetic property of oxygen

It has long been known that the addition of Cu to Al interconnects improves the resistance to electromigration failure. It is generally accepted that this improvement is the result of Cu segregation to Al grain boundaries. The exact mechanism by which segregated Cu increases service lifetime is not understood, although it has been suggested that the formation of thin layers of θ-CuA12 (or some metastable substoichiometric precursor, θ’ or θ”) at the boundaries may be necessary. This paper reports measurements of the local electronic structure of Cu atoms segregated to Al grain boundaries using spatially resolved EELS in a UHV STEM. It is shown that segregated Cu exists in a chemical environment similar to that of Cu atoms in bulk θ-phase precipitates.Films of 100 nm thickness and nominal composition Al-2.5wt%Cu were deposited by sputtering from alloy targets onto NaCl substrates. The samples were solution heat treated at 748K for 30 min and aged at 523K for 4 h to promote equilibrium grain boundary segregation. EELS measurements were made using a Gatan 666 PEELS spectrometer interfaced to a VG HB501 STEM operating at 100 keV. The probe size was estimated to be 1 nm FWHM. Grain boundaries with the narrowest projected width were chosen for analysis. EDX measurements of Cu segregation were made using a VG HB603 STEM.

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An integrated screening method for evaluating the pulmonary toxicity of inhaled particulates: Role of microscopic techniques in assessing pulmonary macrophage clearance functions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100161692 ◽

1990 ◽

Vol 48 (3) ◽

pp. 826-827

Author(s):

David B. Warheit ◽

Lena Achinko ◽

Mark A. Hartsky

Keyword(s):

Bronchoalveolar Lavage ◽

Pulmonary Toxicity ◽

Screening Method ◽

Pulmonary Response ◽

Inhaled Particles ◽

Cytochemical Analysis ◽

Pulmonary Macrophages ◽

Integrated Screening

There is a great need for the development of a rapid and reliable bioassay to evaluate the pulmonary toxicity of inhaled particles. A number of methods have been proposed, including lung clearance studies, bronchoalveolar lavage analysis, and in vitro cytotoxicity tests. These methods are often limited in scope inasmuch as they measure only one dimension of the pulmonary response to inhaled, instilled or incubated dusts. Accordingly, a comprehensive approach to lung toxicity studies has been developed.To validate the method, rats were exposed for 6 hours or 3 days to various concentrations of either aerosolized alpha quartz silica (Si) or carbonyl iron (CI) particles. Cells and fluids from groups of sham and dust-exposed animals were recovered by bronchoalveolar lavage (BAL). Alkaline phosphatase, LDH and protein values were measured in BAL fluids at several time points postexposure. Cells were counted and evaluated for viability, as well as differential and cytochemical analysis. In addition, pulmonary macrophages (PM) were cultured and studied for morphology, chemotaxis, and phagocytosis by scanning electron microscopy.

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Electronic structure studies of conducting polymers by electron energy-loss spectroscopy

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163265 ◽

1996 ◽

Vol 54 ◽

pp. 160-161

Author(s):

J. Fink

Keyword(s):

Electronic Structure ◽

Conducting Polymers ◽

Conjugated Polymers ◽

Electron Acceptors ◽

Electron Donors ◽

Light Emitting ◽

One Dimensional ◽

New Class ◽

Electrical Conductivities ◽

Electron Energy Loss

Conducting polymers comprises a new class of materials achieving electrical conductivities which rival those of the best metals. The parent compounds (conjugated polymers) are quasi-one-dimensional semiconductors. These polymers can be doped by electron acceptors or electron donors. The prototype of these materials is polyacetylene (PA). There are various other conjugated polymers such as polyparaphenylene, polyphenylenevinylene, polypoyrrole or polythiophene. The doped systems, i.e. the conducting polymers, have intersting potential technological applications such as replacement of conventional metals in electronic shielding and antistatic equipment, rechargable batteries, and flexible light emitting diodes.Although these systems have been investigated almost 20 years, the electronic structure of the doped metallic systems is not clear and even the reason for the gap in undoped semiconducting systems is under discussion.

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Electronic Structure and Magnetism of Inorganic Compounds

10.1039/9781847555922 ◽

1973 ◽

Keyword(s):

Electronic Structure ◽

Inorganic Compounds

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Electronic Structure and Magnetism of Inorganic Compounds

10.1039/9781847555977 ◽

1982 ◽

Cited By ~ 1

Keyword(s):

Electronic Structure ◽

Inorganic Compounds

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Doping effects on the geometric and electronic structure of tin clusters

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05124d ◽

2019 ◽

Vol 21 (44) ◽

pp. 24478-24488 ◽

Cited By ~ 1

Author(s):

Martin Gleditzsch ◽

Marc Jäger ◽

Lukáš F. Pašteka ◽

Armin Shayeghi ◽

Rolf Schäfer

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Density Functional ◽

Beam Deflection ◽

Functional Theory ◽

Doping Effects ◽

Depth Analysis ◽

Trajectory Simulations

In depth analysis of doping effects on the geometric and electronic structure of tin clusters via electric beam deflection, numerical trajectory simulations and density functional theory.

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A novel ligand with –NH2 and –COOH-decorated Co/Fe-based oxide for an efficient overall water splitting: dual modulation roles of active sites and local electronic structure

Catalysis Science & Technology ◽

10.1039/d0cy01109f ◽

2020 ◽

Vol 10 (18) ◽

pp. 6266-6273

Author(s):

Yalan Zhang ◽

Zebin Yu ◽

Ronghua Jiang ◽

Jung Huang ◽

Yanping Hou ◽

...

Keyword(s):

Electronic Structure ◽

Water Splitting ◽

Energy Demand ◽

Active Sites ◽

Electrode Materials ◽

Global Energy ◽

Overall Water Splitting ◽

Local Electronic Structure ◽

Electrochemical Water Splitting

Excellent electrochemical water splitting with remarkable durability can provide a solution to satisfy the increasing global energy demand in which the electrode materials play an important role.

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