Does Hydrophilicity of Carbon Particles Improve Their Ice Nucleation Ability?

2014 ◽  
Vol 118 (35) ◽  
pp. 7330-7337 ◽  
Author(s):  
Laura Lupi ◽  
Valeria Molinero
Nature ◽  
1964 ◽  
Vol 201 (4924) ◽  
pp. 1091-1092 ◽  
Author(s):  
V. A. GARTEN ◽  
R. B. HEAD

2016 ◽  
Vol 16 (4) ◽  
pp. 2611-2629 ◽  
Author(s):  
Sylvia C. Sullivan ◽  
Ricardo Morales Betancourt ◽  
Donifan Barahona ◽  
Athanasios Nenes

Abstract. Along with minimizing parameter uncertainty, understanding the cause of temporal and spatial variability of the nucleated ice crystal number, Ni, is key to improving the representation of cirrus clouds in climate models. To this end, sensitivities of Ni to input variables like aerosol number and diameter provide valuable information about nucleation regime and efficiency for a given model formulation. Here we use the adjoint model of the adjoint of a cirrus formation parameterization (Barahona and Nenes, 2009b) to understand Ni variability for various ice-nucleating particle (INP) spectra. Inputs are generated with the Community Atmosphere Model version 5, and simulations are done with a theoretically derived spectrum, an empirical lab-based spectrum and two field-based empirical spectra that differ in the nucleation threshold for black carbon particles and in the active site density for dust. The magnitude and sign of Ni sensitivity to insoluble aerosol number can be directly linked to nucleation regime and efficiency of various INP. The lab-based spectrum calculates much higher INP efficiencies than field-based ones, which reveals a disparity in aerosol surface properties. Ni sensitivity to temperature tends to be low, due to the compensating effects of temperature on INP spectrum parameters; this low temperature sensitivity regime has been experimentally reported before but never deconstructed as done here.


2020 ◽  
Vol 47 (11) ◽  
Author(s):  
Zamin A. Kanji ◽  
André Welti ◽  
Joel C. Corbin ◽  
Amewu A. Mensah

1969 ◽  
Vol 22 (03) ◽  
pp. 496-507 ◽  
Author(s):  
W.G van Aken ◽  
J Vreeken

SummaryCarbon particles cause platelet aggregation in vitro and in vivo. Prior studies established that substances which modify thrombocyte aggregation also influence the rate at which carbon is cleared from the blood.This study was performed in order to elucidate the mechanism by which the carbon-platelet aggregates specifically accumulate in the RES.Activation of fibrinolysis by urokinase or streptokinase reduced the carbon clearance rate, probably due to generated fibrinogen degradation products (FDP). Isolated FDP decreased the carbon clearance and caused disaggregation of platelets and particles in vitro. Inhibition of fibrinolysis by epsilon-amino-caproic acid (EACA), initially accelerated the disappearance of carbon and caused particle accumulation outside the RES, predominantly in the lungs. It is supposed that platelet aggregation and locally activated fibrinolysis act together in the clearance of particles. In the normal situation the RES with its well known low fibrinolytic activity, becomes the receptor of the particles.


Alloy Digest ◽  
1969 ◽  
Vol 18 (11) ◽  

Abstract Haynes Stellite No. 4 is a cobalt-base cast alloy recommended for handling severe conditions of abrasion, heat and corrosion. It is especially recommended to resist the severe abrasive and corrosive action of manganese dioxide, carbon particles, and ammonium and zinc chlorides in the battery mix used in the manufacture of dry batteries. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as heat treating, machining, and joining. Filing Code: Co-59. Producer or source: Union Carbide Materials Systems Division.


Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 896
Author(s):  
Matthias Schmitt ◽  
Albin Gottwalt ◽  
Jakob Winkler ◽  
Thomas Tobie ◽  
Georg Schlick ◽  
...  

The carbon content of steel affects many of its essential properties, e.g., hardness and mechanical strength. In the powder bed fusion process of metals using a laser beam (PBF-LB/M), usually, pre-alloyed metal powder is solidified layer-by-layer using a laser beam to create parts. A reduction of the carbon content in steels is observed during this process. This study examines adding carbon particles to the metal powder and in situ alloying in the PBF-LB/M process as a countermeasure. Suitable carbon particles are selected and their effect on the particle size distribution and homogeneity of the mixtures is analysed. The workability in PBF-LB is then shown. This is followed by an evaluation of the resulting mechanical properties (hardness and mechanical strength) and microstructure in the as-built state and the state after heat treatment. Furthermore, potential use cases like multi-material or functionally graded parts are discussed.


Author(s):  
Philipp Baloh ◽  
Regina Hanlon ◽  
Christopher Anderson ◽  
Eoin Dolan ◽  
Gernot Pacholik ◽  
...  

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