Shock-darkening in ordinary chondrites: Determination of the pressure-temperature conditions by shock physics mesoscale modeling

PurposeTo determine static friction coefficients between rapid tooled materials and thermoplastic materials to better understand ejection force requirements for the injection molding process using rapid‐tooled mold inserts.Design/methodology/approachStatic coefficients of friction were determined for semi‐crystalline high‐density polyethylene (HDPE) and amorphous high‐impact polystyrene (HIPS) against two rapid tooling materials, sintered steel with bronze (LaserForm ST‐100) and stereolithography resin (SL5170), and against P‐20 mold steel. Friction tests, using the ASTM D 1894 standard, were run for all material pairs at room temperature, at typical part ejection temperatures, and at ejection temperatures preceded by processing temperatures. The tests at high temperature were designed to simulate injection molding process conditions.FindingsThe friction coefficients for HDPE were similar on P‐20 Steel, LaserForm ST‐100, and SL5170 Resin at all temperature conditions. The HIPS coefficients, however, varied significantly among tooling materials in heated tests. Both polymers showed highest coefficients on SL5170 Resin at all temperature conditions. Friction coefficients were especially high for HIPS on the SL5170 Resin tooling material.Research limitations/implicationsApplications of these findings must consider that elevated temperature tests more closely simulated the injection‐molding environment, but did not exactly duplicate it.Practical implicationsThe data obtained from these tests allow for more accurate determination of friction conditions and ejection forces, which can improve future design of injection molds using rapid tooling technologies.Originality/valueThis work provides previously unavailable friction data for two common thermoplastics against two rapid tooling materials and one steel tooling material, and under conditions that more closely simulate the injection‐molding environment.

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Determination of quadrupole splitting for 57Fe in M1 and M2 sites of both olivine and pyroxene in ordinary chondrites using Mössbauer spectroscopy with high velocity resolution

HFI/NQI 2007 ◽

10.1007/978-3-540-85320-6_30 ◽

2008 ◽

pp. 193-199

Author(s):

M. I. Oshtrakh ◽

E. V. Petrova ◽

V. I. Grokhovsky ◽

V. A. Semionkin

Keyword(s):

Mössbauer Spectroscopy ◽

Quadrupole Splitting ◽

High Velocity ◽

Mossbauer Spectroscopy ◽

Ordinary Chondrites ◽

High Velocity Resolution ◽

Mößbauer Spectroscopy

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Determination of quadrupole splitting for 57Fe in M1 and M2 sites of both olivine and pyroxene in ordinary chondrites using Mössbauer spectroscopy with high velocity resolution

Hyperfine Interactions ◽

10.1007/s10751-008-9646-4 ◽

2007 ◽

Vol 177 (1-3) ◽

pp. 65-71 ◽

Cited By ~ 14

Author(s):

M. I. Oshtrakh ◽

E. V. Petrova ◽

V. I. Grokhovsky ◽

V. A. Semionkin

Keyword(s):

Mössbauer Spectroscopy ◽

Quadrupole Splitting ◽

High Velocity ◽

Mossbauer Spectroscopy ◽

Ordinary Chondrites ◽

High Velocity Resolution ◽

Mößbauer Spectroscopy

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Application of Mössbauer spectroscopy for classification of ordinary chondrites – different database and different methods

Hyperfine Interactions ◽

10.1007/s10751-019-1661-0 ◽

2019 ◽

Vol 241 (1) ◽

Cited By ~ 1

Author(s):

Jolanta Gałązka-Friedman ◽

Marek Woźniak ◽

Patrycja Bogusz ◽

Martyna Jakubowska ◽

Łukasz Karwowski ◽

...

Keyword(s):

Mössbauer Spectroscopy ◽

Discriminant Analysis ◽

Quantitative Method ◽

Mossbauer Spectroscopy ◽

Classical Method ◽

Short Review ◽

Ordinary Chondrites ◽

Mößbauer Spectroscopy

AbstractClassification of the meteorites is very complex, but in general all meteorites can be divided into three groups: stony, iron and stony-iron. Ordinary chondrites are the most numerous group among stony meteorites. In this paper, we present short review of the methods of classification of ordinary chondrites. The classical method for the classification of ordinary chondrites is based on the determination of the content of fayalite in olivine and of the content of ferrosilite in pyroxene with the use of electron microprobe. This method was proposed in 1967. Studies on the application of Mössbauer spectroscopy to classification of ordinary chondrites were carried out since early 2000 in four Mössbauer laboratories. Mössbauer groups from Kanpur, Ekaterinburg and Canberra suggested qualitative methods of classification of ordinary chondrites. Warsaw group created quantitative method called the “4M method”. This name derives from following words: meteorites, Mössbauer spectroscopy, multidimensional discriminant analysis, Mahalanobis distance. In this publication, we describe the use of 4M method for reclassification of meteorite Goronyo.

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Etude de l'adsorption de surfactants ioniques et non ioniques sur de la matière végétale carbonisée

Canadian Journal of Chemistry ◽

10.1139/v81-004 ◽

1981 ◽

Vol 59 (1) ◽

pp. 19-26 ◽

Cited By ~ 11

Author(s):

Francis Perineau ◽

Antoine Gaset

Keyword(s):

Chain Length ◽

Adsorption Kinetics ◽

Plant Material ◽

Adsorption Process ◽

Hydrophobic Interactions ◽

Square Root ◽

Temperature Conditions ◽

Liquid Wastes

The aim of this investigation was to assess the possible use of sulfuric lignins for the purification of industrial liquid wastes. The adsorption of anionic (SDS), cationic (CPC), and non-ionic (NPPO) surfactants on charred plant material was carried out under various pH and temperature conditions. Ionic and hydrophobic interactions are involved in the adsorption process. The analysis of the adsorption kinetics in aqueous and alcoholic media allowed the mode of adsorption to be characterized. The plot of the surfactant uptake against the square root of time led to the determination of the mode of diffusion. The effect of the chain length of alkylsulfates on their adsorption corroborated the involvement of hydrophobic interactions and could be correlated with the values of their cmc.

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