Disperse-Hardened Composite Production of Homogeneous Chemical Composition by Electroslag Cladding and Remelting

AbstractRecent spectroscopic observations of comets, obtained especially in the vacuum ultraviolet spectral region from sounding rockets and satellites, have considerably increased our knowledge of the chemical composition of comets, and the physical and chemical processes occurring in their head and tail. From the UV spectra of comets observed so far, one can perhaps conclude that they have a very similar, homogeneous chemical composition, and possibly also a common origin.

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High Temperature Thermoelectric Property of Sr-Filled Skutterudite SryCo4Sb12

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.336-338.842 ◽

2007 ◽

Vol 336-338 ◽

pp. 842-845

Author(s):

Xue Ying Zhao ◽

Xun Shi ◽

Li Dong Chen ◽

Sheng Qiang Bai ◽

Wen Bing Zhang ◽

...

Keyword(s):

Thermal Conductivity ◽

Electrical Conductivity ◽

Chemical Composition ◽

Seebeck Coefficient ◽

Figure Of Merit ◽

Thermoelectric Figure ◽

Filled Skutterudite ◽

Absolute Value ◽

Homogeneous Chemical ◽

Type Conduction

Sr-filled skutterudite compounds SryCo4Sb12 (y=0-0.20) were synthesized by melting method. XRD and EPMA results revealed that the obtained samples are single skutterudite phase with homogeneous chemical composition. The lattice parameters increase linearly with increasing Sr content in the range of y=0-0.20. The thermal conductivity, electrical conductivity and Seebeck coefficient were measured in the temperature range of 300-850K. The measurement of Hall effect was performed by Van de Pauw method at room temperature. The obtained Sr-filled skutterudite exhibits n-type conduction. The absolute value of the Seebeck coefficient of SryCo4Sb12 decreases with the increase of Sr content. The electrical conductivity increases with the increase of Sr content. The lattice thermal conductivity of SryCo4Sb12 is significantly depressed as compared with unfilled CoSb3. The maximum dimensionless thermoelectric figure of merit is 0.7 for Sr0.20Co4Sb12 at 850K. Further optimization of chemical composition would improve the thermoelectric performance.

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Rice waste–based polymer composites for packaging applications: A review

Polymers and Polymer Composites ◽

10.1177/09673911211046775 ◽

2021 ◽

pp. 096739112110467

Author(s):

Waham Ashaier Laftah ◽

Wan Aizan Wan Abdul Rahman

Keyword(s):

Chemical Composition ◽

Polymer Composites ◽

Production Cost ◽

Low Cost ◽

Point Of View ◽

Packaging Materials ◽

Composite Polymers ◽

Green Packaging ◽

Composite Production ◽

Main Factor

Rice wastes are abundant, low-cost, cellulosic-based materials. The potential of using rice waste such as husk, straw, and bran in bio-composite production is a crucial target of the composite industry. Chemical composition is the main factor that offers diverse possible applications of rice wastes in bio-composite-based materials. Eco-friendly products of bio-composite polymers can be produced by reinforcing and filling polymer matrices with high cellulosic content materials such as rice waste. From manufacturing point of view, rice wastes can be used to reduce the production cost of polymer-based products and meet the requirements for green packaging materials.

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High Oxygen Abundance in a Bright Filament of the Crab Nebula

Symposium - International Astronomical Union ◽

10.1017/s0074180900033805 ◽

1983 ◽

Vol 101 ◽

pp. 149-151

Author(s):

Daniel Péquignot

Keyword(s):

Chemical Composition ◽

Planetary Nebula ◽

Near Infrared ◽

Crab Nebula ◽

The Other ◽

High Excitation ◽

Exchange Reactions ◽

Ngc 7027 ◽

Homogeneous Chemical ◽

The Crab Nebula

Detailed stationary photoionization models with homogeneous chemical composition were constructed for a bright filament of the Crab Nebula centered ~42″ W-SW of the pulsar. So far this filament is the only one which has been observed in the ultraviolet (Davidson et al, 1982), in the visual (Miller, 1978; Davidson et al, 1982) and in the near-infrared (Dennefeld and Péquignot, 1982), so that numerous constraints and meaningful tests of the models exist. On the other hand the computer program used in the calculations includes recently introduced atomic physics processes (charge exchange reactions and “low-temperature” di-electronic recombinations) and was tested and calibrated by means of models of the high-excitation planetary nebula NGC 7027 whose line spectrum shares some characteristics with that of the Crab Nebula.

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Stratified NLTE Model Atmospheres for Hot Stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900133224 ◽

2003 ◽

Vol 210 ◽

pp. 33-43

Author(s):

Stefan Dreizler ◽

Sonja L. Schuh

Keyword(s):

Chemical Composition ◽

Cross Sections ◽

Stellar Atmosphere ◽

Hot Stars ◽

Gravitational Settling ◽

Self Consistent ◽

Chemical Stratification ◽

The Status ◽

Homogeneous Chemical ◽

Radiative Acceleration

In most stellar atmosphere models, a homogeneous chemical composition is assumed, which is a good approximation for many stars. With the absence of convection and mass–loss, however, gravitational settling can produce a chemical stratification gradient. Typical examples are white dwarfs. In hot stars this diffusion process is modified by the radiative acceleration, resulting in levitation of ions with large radiative cross sections. The status of our program for self-consistent stratified non-LTE model atmospheres is presented.

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Surface-controlled spatially heterogeneous physical properties of a supramolecular gel with homogeneous chemical composition

Chemical Science ◽

10.1039/d1sc04671c ◽

2021 ◽

Author(s):

Bin Yang ◽

Marina Lledos ◽

Riaz Akhtar ◽

Giuseppe Ciccone ◽

Long Jiang ◽

...

Keyword(s):

Chemical Composition ◽

Physical Properties ◽

Self Assembly ◽

Length Scales ◽

Supramolecular Gel ◽

Multiple Length Scales ◽

Homogeneous Chemical

Controlling supramolecular self-assembly across multiple length scales to prepare gels with localised properties is challenging. Most strategies concentrate on fabricating gels with heterogeneous components, where localised properties are generated by...

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The Origin of the Moon

Symposium - International Astronomical Union ◽

10.1017/s0074180900178209 ◽

1962 ◽

Vol 14 ◽

pp. 149-155 ◽

Cited By ~ 1

Author(s):

E. L. Ruskol

Keyword(s):

Chemical Composition ◽

Solar System ◽

The Moon ◽

The Earth ◽

The Difference ◽

Origin Of The Moon

The difference between average densities of the Moon and Earth was interpreted in the preceding report by Professor H. Urey as indicating a difference in their chemical composition. Therefore, Urey assumes the Moon's formation to have taken place far away from the Earth, under conditions differing substantially from the conditions of Earth's formation. In such a case, the Earth should have captured the Moon. As is admitted by Professor Urey himself, such a capture is a very improbable event. In addition, an assumption that the “lunar” dimensions were representative of protoplanetary bodies in the entire solar system encounters great difficulties.

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On the Inhomogeneity of Chemical Composition over the Surface of 21 Per

International Astronomical Union Colloquium ◽

10.1017/s0252921100080659 ◽

1976 ◽

Vol 32 ◽

pp. 343-349

Author(s):

Yu.V. Glagolevsky ◽

K.I. Kozlova ◽

V.S. Lebedev ◽

N.S. Polosukhina

Keyword(s):

Chemical Composition ◽

Spectral Line ◽

Variable Star ◽

Radial Velocities ◽

Crimean Astrophysical Observatory ◽

Line Intensities ◽

Magnetic Variable

SummaryThe magnetic variable star 21 Per has been studied from 4 and 8 Å/mm spectra obtained with the 2.6 - meter reflector of the Crimean Astrophysical Observatory. Spectral line intensities (Wλ) and radial velocities (Vr) have been measured.

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Structural Studies on Mitotic Spindle Fibres

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070345 ◽

1978 ◽

Vol 36 (3) ◽

pp. 615-626

Author(s):

J.R. Mcintosh

Keyword(s):

Chemical Composition ◽

Mitotic Spindle ◽

Structural Studies ◽

Mitotic Apparatus ◽

Chemical Studies ◽

Medical Interest ◽

Spindle Fibres

The mitotic apparatus is a structure of obvious biological and medical interest, but it has proved to be a difficult cellular machine to understand. The chemical composition of the spindle is only slightly elucidated, largely because of the difficulties in preparing useful isolates of the structure. Chemical studies of the mitotic spindle have been reviewed elsewhere (Mcintosh, 1977), and will not be discussed further here. One would think that structural studies on the mitotic apparatus (MA) in situ would be straightforward, but even with this approach there is some disagreement in the results obtained with various methods and by different investigators. In this paper I will review briefly the approaches which have been used in structural studies of the MA, pointing out the strengths and problems of each approach. I will summarize the principal findings of the different methods, and identify what seem to be fruitful avenues for further work.

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Effects of 5-5'-Diphenyl-2-thiohydantoin (DPTH) and Thyroxine on the Ultrastructure and Chemical Composition of Rat Liver

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066917 ◽

1971 ◽

Vol 29 ◽

pp. 570-571

Author(s):

E. A. Elfont ◽

R. B. Tobin ◽

D. G. Colton ◽

M. A. Mehlman

Keyword(s):

Chemical Composition ◽

Rat Liver ◽

Future Study ◽

Mode Of Action ◽

Liver Mitochondria ◽

Rat Liver Mitochondria ◽

Effective Inhibitor ◽

Biochemical Effects ◽

Glycerophosphate Dehydrogenase ◽

Stimulation Of

Summary5,-5'-diphenyl-2-thiohydantoin (DPTH) is an effective inhibitor of thyroxine (T4) stimulation of α-glycerophosphate dehydrogenase in rat liver mitochondria. Because this finding indicated a possible tool for future study of the mode of action of thyroxine, the ultrastructural and biochemical effects of DPTH and/or thyroxine on rat liver mere investigated.Rats were fed either standard or DPTH (0.06%) diet for 30 days before T4 (250 ug/kg/day) was injected. Injection of T4 occurred daily for 10 days prior to sacrifice. After removal of the liver and kidneys, part of the tissue was frozen at -50°C for later biocheailcal analyses, while the rest was prefixed in buffered 3.5X glutaraldehyde (390 mOs) and post-fixed in buffered 1Z OsO4 (376 mOs). Tissues were embedded in Araldlte 502 and the sections examined in a Zeiss EM 9S.Hepatocytes from hyperthyroid rats (Fig. 2) demonstrated enlarged and more numerous mitochondria than those of controls (Fig. 1). Glycogen was almost totally absent from the cytoplasm of the T4-treated rats.

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