Aerosol charging and capture in the nanoparticle size range (6–15nm) by direct photoionization and diffusion mechanisms

In prominent funding and policy statements, a particle with at least one dimension in the 1-300 nm size range must have novel physicochemical properties to count as a “nanoparticle.” Size is thus only one factor. Novelty of a particle's properties is also essential to its “nano” classification. When particles in this size range are introduced into living systems, they often interact with their host in novel ways that require some modification of existing methods and models used by pharmaceutical scientists and toxicologists for assessing their efficacy and safety. It is not clear, however, whether the novelty of the intended physicochemical properties is in any way related to the novel behavior of those particles when their toxicity is evaluated. In fact, when considering toxicity, much of the concern about nanoparticles relates to the unanticipated or poorly understood interactions.

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THE STABILITY OF LOW INDEX METAL SURFACES TO TOPOLOGICAL DEFECTS

International Journal of Modern Physics B ◽

10.1142/s0217979291000274 ◽

1991 ◽

Vol 05 (03) ◽

pp. 427-459 ◽

Cited By ~ 3

Author(s):

EDWARD H. CONRAD

Keyword(s):

Metal Surfaces ◽

Surface Defects ◽

Defect Formation ◽

Fundamental Problem ◽

Topological Defects ◽

Surface Roughening ◽

Thermal Generation ◽

Diffusion Mechanisms ◽

The Stability ◽

And Diffusion

The study of defect formation at metal surfaces is a fundamental problem in surface physics. An understanding of defect formation is pertinent to growth and diffusion mechanisms. In addition, surface roughening, faceting, and surface melting are all defect mediated phase transitions involving the formation of different topological defects. While the importance of defects at surfaces is well recognized, the study of surface defects has been hampered by the lack of sufficiently accurate experimental techniques. In fact, it is only in the past 6 years that experiments on the thermal generation of defects on metal surfaces have been performed. This review attempts to outline both the theoretical and experimental work on surface defect formation on metal systems.

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New Tight-Binding Method for Simulation of Defect Configurations, Creation and Diffusion Mechanisms in Solids: Application to Silicon

MRS Proceedings ◽

10.1557/proc-527-369 ◽

1998 ◽

Vol 527 ◽

Author(s):

Zokirkhon M. Khakimov

Keyword(s):

Tight Binding ◽

The Self ◽

Atomic Diffusion ◽

Self Consistent ◽

Tight Binding Method ◽

Comparable Accuracy ◽

Diffusion Mechanisms ◽

New Generation ◽

And Diffusion ◽

Metastable Defect

ABSTRACTThis paper presents the self-consistent tight-binding method of new generation which, unlike other tight-binding methods, allows one to calculate structural energies of multiatomic systems (molecules, clusters, defects in solids) and their spectroscopic energies in the framework of the same computational scheme and with comparable accuracy. Reliability of the method is illustrated considering defect state problems in crystalline and amorphous silicon (electron-enhanced-atomic diffusion, metastable defect creation, defects with effective-negative correlation energies, etc.) and comparing obtained results with ab initio calculations and experimental data.

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Thermal conductivity and diffusion mechanisms of noble gases in uranium dioxide: A DFT+U study

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2019.04.040 ◽

2019 ◽

Vol 521 ◽

pp. 137-145 ◽

Cited By ~ 8

Author(s):

E. Torres ◽

T.P. Kaloni

Keyword(s):

Thermal Conductivity ◽

Uranium Dioxide ◽

Noble Gases ◽

Diffusion Mechanisms ◽

And Diffusion

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Diffusion of Chloride and Uranium in Compacted Sodium Bentonite

MRS Proceedings ◽

10.1557/proc-127-743 ◽

1988 ◽

Vol 127 ◽

Cited By ~ 21

Author(s):

Arto Muurinen ◽

Pirkkd Pemtilä-Hiltunen ◽

Kari Uusheimo

Keyword(s):

Salt Concentration ◽

Sodium Bentonite ◽

Ion Exclusion ◽

Diffusion Mechanisms ◽

And Diffusion

ABSTRACTSorption and diffusion of chloride (Cl-36) and uranium in conpacted sodium bentonite MX-80 were measured. No sorption was observed in the Sorption tests, however, in the diffusion tests slight sorption of uranium was noticed. The diffusivities of Cl-36 were found to be strongly dependent on the compaction of bentonite and on the salt concentration of the solution. Ion-exclusion can propably explain these phenomena.The diffusivities of uranium were also strongly dependent on the compaction of bentonite. Uranium shews features of both ion-exclusion and sorption. Farther studies are, however, needed to explain the diffusion mechanisms of uranium.

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New Tight-Binding Method for Simulation of Defect Configurations, Creation and Diffusion Mechanisms in Solids: Application to Silicon

MRS Proceedings ◽

10.1557/proc-532-205 ◽

1998 ◽

Vol 532 ◽

Author(s):

Zokirkhon M. Khakimov

Keyword(s):

Tight Binding ◽

The Self ◽

Atomic Diffusion ◽

Self Consistent ◽

Tight Binding Method ◽

Comparable Accuracy ◽

Diffusion Mechanisms ◽

New Generation ◽

And Diffusion ◽

Metastable Defect

ABSTRACTThis paper presents the self-consistent tight-binding method of new generation which, unlike other tight-binding methods, allows one to calculate structural energies of multiatomic systems (molecules, clusters, defects in solids) and their spectroscopic energies in the framework of the same computational scheme and with comparable accuracy. Reliability of the method is illustrated considering defect state problems in crystalline and amorphous silicon (electronenhanced- atomic diffusion, metastable defect creation, defects with effective-negative correlation energies, etc.) and comparing obtained results with ab initio calculations and experimental data.

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