Dense Suspension Splat: Monolayer Spreading and Hole Formation after Impact

During recent experiments on Au films, a qualitative correlation between hole formation and deposition rate was observed. These early studies were concerned with films 80 to 1000A thick deposited on glass at -185°C and annealed at 170°C. In the present studies this earlier work was made quantitative. Deposition rates varying between 5 and 700 A/min were used. The effects of deposition rate on hole density for two films 300 and 700A thick were investigated.Au was evaporated from an outgassed W filament located 10 cm from a glass microscope slide substrate and a quartz crystal film thickness monitor. A shutter separating the filament from the substrate and monitor made it possible to obtain a constant evaporation rate before initiating deposition. The pressure was reduced to less than 1 x 10-6 torr prior to cooling the substrate with liquid nitrogen. The substrate was cooled in 15 minutes during which the pressure continued to drop to the mid 10-7 torr range, where deposition was begun.

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Comparative strengths and weaknesses of peroxidase and colloidal gold in pre- and post-embedding immunolabeling techniques

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100129279 ◽

1987 ◽

Vol 45 ◽

pp. 1002-1005

Author(s):

D. R. Abrahamson ◽

P. L. St.John ◽

E. W. Perry

Keyword(s):

Electron Microscopy ◽

Horseradish Peroxidase ◽

Light Microscopy ◽

Colloidal Gold ◽

Light Microscope ◽

Ultrastructural Localization ◽

The Other ◽

Quantitative Studies ◽

Dense Suspension ◽

Antigen Localization

Antibodies coupled to tracers for electron microscopy have been instrumental in the ultrastructural localization of antigens within cells and tissues. Among the most popular tracers are horseradish peroxidase (HRP), an enzyme that yields an osmiophilic reaction product, and colloidal gold, an electron dense suspension of particles. Some advantages of IgG-HRP conjugates are that they are readily synthesized, relatively small, and the immunolabeling obtained in a given experiment can be evaluated in the light microscope. In contrast, colloidal gold conjugates are available in different size ranges and multiple labeling as well as quantitative studies can therefore be undertaken through particle counting. On the other hand, gold conjugates are generally larger than those of HRP but usually can not be visualized with light microscopy. Concern has been raised, however, that HRP reaction product, which is exquisitely sensitive when generated properly, may in some cases distribute to sites distant from the original binding of the conjugate and therefore result in spurious antigen localization.

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The theory of black hole formation shares the Nobel Prize in Physics

Physics Today ◽

10.1063/pt.3.4628 ◽

2020 ◽

Vol 73 (12) ◽

pp. 14-17

Author(s):

Heather M. Hill

Keyword(s):

Black Hole ◽

Nobel Prize ◽

Hole Formation ◽

Black Hole Formation ◽

Nobel Prize In Physics

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Lithological Control on Scour Hole Formation in the Rhine-Meuse Estuary

Geomorphology ◽

10.1016/j.geomorph.2021.107720 ◽

2021 ◽

pp. 107720

Author(s):

Ymkje Huismans ◽

Hilde Koopmans ◽

Ane Wiersma ◽

Tjalling de Haas ◽

Koen Berends ◽

...

Keyword(s):

Hole Formation ◽

Scour Hole

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Feeding and feedback from little monsters: AGN in dwarf galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921320002240 ◽

2020 ◽

Vol 15 (S359) ◽

pp. 238-242

Author(s):

Mar Mezcua

Keyword(s):

Black Holes ◽

Black Hole ◽

Early Universe ◽

Dwarf Galaxies ◽

Scaling Relations ◽

Strong Impact ◽

Hole Formation ◽

Intermediate Mass ◽

Black Hole Formation ◽

Low Mass

AbstractDetecting the seed black holes from which quasars formed is extremely challenging; however, those seeds that did not grow into supermassive should be found as intermediate-mass black holes (IMBHs) of 100 – 105 M⊙ in local dwarf galaxies. The use of deep multiwavelength surveys has revealed that a population of actively accreting IMBHs (low-mass AGN) exists in dwarf galaxies at least out to z ˜3. The black hole occupation fraction of these galaxies suggests that the early Universe seed black holes formed from direct collapse of gas, which is reinforced by the possible flattening of the black hole-galaxy scaling relations at the low-mass end. This scenario is however challenged by the finding that AGN feedback can have a strong impact on dwarf galaxies, which implies that low-mass AGN in dwarf galaxies might not be the untouched relics of the early seed black holes. This has important implications for seed black hole formation models.

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Generalized modeling of drilling vibrations. Part I: Time domain model of drilling kinematics, dynamics and hole formation

International Journal of Machine Tools and Manufacture ◽

10.1016/j.ijmachtools.2006.10.005 ◽

2007 ◽

Vol 47 (9) ◽

pp. 1455-1473 ◽

Cited By ~ 49

Author(s):

Jochem C. Roukema ◽

Yusuf Altintas

Keyword(s):

Time Domain ◽

Domain Model ◽

Hole Formation

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Quantum channels in quantum gravity

International Journal of Modern Physics D ◽

10.1142/s0218271814420097 ◽

2014 ◽

Vol 23 (12) ◽

pp. 1442009 ◽

Cited By ~ 1

Author(s):

Mukund Rangamani ◽

Massimilliano Rota

Keyword(s):

Field Theory ◽

Black Hole ◽

Quantum Gravity ◽

Path Integrals ◽

Quantum Channels ◽

Hole Formation ◽

Integral Formalism ◽

Final State ◽

State Boundary ◽

Gauge Gravity

The black hole final state proposal implements manifest unitarity in the process of black hole formation and evaporation in quantum gravity, by postulating a unique final state boundary condition at the singularity. We argue that this proposal can be embedded in the gauge/gravity context by invoking a path integral formalism inspired by the Schwinger–Keldysh like thermo-field double construction in the dual field theory. This allows us to realize the gravitational quantum channels for information retrieval to specific deformations of the field theory path integrals and opens up new connections between geometry and information theory.

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Specific Binding of Rubidium in Chlorella

The Journal of General Physiology ◽

10.1085/jgp.45.5.959 ◽

1962 ◽

Vol 45 (5) ◽

pp. 959-977 ◽

Cited By ~ 18

Author(s):

Dan Cohen

Keyword(s):

Active Transport ◽

Binding Sites ◽

Specific Binding ◽

High Concentration ◽

External Concentration ◽

Specific Binding Sites ◽

Dense Suspension ◽

Concentration Of Ions ◽

The Individual ◽

A Site

Specific binding sites for potassium, which may be components of the carriers for active transport for K in Chlorella, were characterized by their capacity to bind rubidium. A dense suspension was allowed to take up Rb86 from a low concentration of Rb86 and a high concentration of ions which saturate non-specific sites. The amount bound was derived from the increase in the external concentration of Rb86 following addition of excess potassium. The sites were heterogeneous. The average affinity of Rb and various other ions for the sites was determined by plotting the degree of displacement of Rb86 against log molar concentration of the individual ions. Interpolation gave the concentration for 50 per cent displacement of Rb, which is inversely related to affinity. The order of affinity was not changed when the cells were frozen, or boiled either in water or in 70 per cent ethanol. The affinity is maximal for ions with a crystalline radius of 1.3 to 1.5 A and a high polarizability, and is not related to the hydrated radius or valency. It is suggested that binding groups in a site are rigidly arranged, the irregular space between them being 2.6 to 3.0 A across, so that affinity is high for ions of this diameter and high polarizability.

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