Fire-resistant hydrophobic nanocoated composite partition sheets

Composite partition sheets were prepared by vacuum infusion process using noncombustible glass fiber and waste nylon along with polyester matrix. The waste nylon materials obtained in the form of discarded fishing nets were reinforced in sheets with T90° orientation. They were then coated using two types of fumed silica nanopowders mixed in polyester resin. Two types of coated and corresponding bare hybrid composite samples were examined for their various properties. Appreciable values for mechanical properties were obtained for all the hybrid sheets which are more pronounced for the nanocoated sheets. Furthermore, horizontal flammability tests proved that the fumed silica-coated sheets have better flame-retardant characteristics. With constant heat flux of 50 W/m2, the specimens were investigated for the peak heat release rate (HRR) and fire reaction properties like total oxygen consumed, average specific mass loss rate, total smoke release, and average HRR which gave good results for the nanocoated sheets. Moreover, water-absorbing properties of the hybrid sheets were generally less and it was better in the case of hydrophobic fumed silica-coated samples. These low cost and less weight composite sheets were successfully developed and the results obtained were encouraging, which can be used as partition sheets in the construction of affordable buildings.

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Supermassive stars as the origin of the multiple populations in globular clusters

Proceedings of the International Astronomical Union ◽

10.1017/s1743921319007658 ◽

2019 ◽

Vol 14 (S351) ◽

pp. 297-301

Author(s):

Mark Gieles ◽

Corinne Charbonnel

Keyword(s):

Globular Clusters ◽

Massive Star ◽

Loss Rate ◽

Mass Loss Rate ◽

Specific Mass ◽

Hydrogen Burning ◽

Multiple Populations ◽

Mass Budget ◽

Processed Material ◽

Stellar Collisions

AbstractGlobular clusters (GCs) display anomalous light-elements abundances (HeCNONaMgAl), resembling the yields of hot-hydrogen burning, but there is no consensus yet on the origin of these ubiquitous multiple populations. We present a model in which a super-massive star (SMS, ≳103 M⊙) forms via stellar collisions during GC formation and pollutes the intra-cluster medium. The growth of the SMS finds a balance with the wind mass loss rate, such that the SMS can produce a significant fraction of the total GC mass in processed material, thereby overcoming the so-called mass-budget problem that plagues other models. Because of continuous rejuvenation, the SMS acts as a ‘conveyer-belt’ of hot-hydrogen burning yields with (relatively) low He abundances, in agreement with empirical constraints. Additionally, the amount of processed material per unit of GC mass correlates with GC mass, addressing the specific mass budget problem. We discuss uncertainties and tests of this new self-enrichment scenario.

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Reaction-to-fire tests. Heat release, smoke production and mass loss rate

10.3403/30282467 ◽

2013 ◽

Keyword(s):

Mass Loss ◽

Heat Release ◽

Loss Rate ◽

Mass Loss Rate ◽

Fire Tests ◽

Smoke Production

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Reaction-to-fire tests. Heat release, smoke production and mass loss rate

10.3403/30354021 ◽

2017 ◽

Keyword(s):

Mass Loss ◽

Heat Release ◽

Loss Rate ◽

Mass Loss Rate ◽

Fire Tests ◽

Smoke Production

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Reaction-to-fire tests. Heat release, smoke production and mass loss rate

10.3403/bsiso5660 ◽

2015 ◽

Keyword(s):

Mass Loss ◽

Heat Release ◽

Loss Rate ◽

Mass Loss Rate ◽

Fire Tests ◽

Smoke Production

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Reaction-to-fire tests � Heat release, smoke production and mass loss rate

10.3403/pdisots5660 ◽

2015 ◽

Keyword(s):

Mass Loss ◽

Heat Release ◽

Loss Rate ◽

Mass Loss Rate ◽

Fire Tests ◽

Smoke Production

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SN 2009ip: CONSTRAINTS ON THE PROGENITOR MASS-LOSS RATE

The Astrophysical Journal ◽

10.1088/0004-637x/768/1/47 ◽

2013 ◽

Vol 768 (1) ◽

pp. 47 ◽

Cited By ~ 42

Author(s):

E. O. Ofek ◽

L. Lin ◽

C. Kouveliotou ◽

G. Younes ◽

E. Göğüş ◽

...

Keyword(s):

Mass Loss ◽

Loss Rate ◽

Mass Loss Rate

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AGB Winds with Gas-Dust Drift in Stellar Evolution Codes

Universe ◽

10.3390/universe7050113 ◽

2021 ◽

Vol 7 (5) ◽

pp. 113

Author(s):

Lars Mattsson ◽

Christer Sandin

Keyword(s):

Stellar Evolution ◽

Loss Rate ◽

Mass Loss Rate ◽

Carbon Star ◽

Intermediate Mass ◽

Future Directions ◽

Physical Description ◽

Intermediate Mass Stars ◽

Dust Component ◽

Improved Model

A significant fraction of new metals produced in stars enter the interstellar medium in the form of dust grains. Including dust and wind formation in stellar evolution models of late-stage low- and intermediate-mass stars provides a way to quantify their contribution to the cosmic dust component. In doing so, a correct physical description of dust formation is of course required, but also a reliable prescription for the mass-loss rate. Here, we present an improved model of dust-driven winds to be used in stellar evolution codes and insights from recent detailed numerical simulations of carbon-star winds including drift (decoupling of dust and gas). We also discuss future directions for further improvement.

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Effect of Sample Width on Downward Flame Spread over Typical Energy Conservation Material at a High Elevation Area

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.664.199 ◽

2014 ◽

Vol 664 ◽

pp. 199-203 ◽

Cited By ~ 1

Author(s):

Wei Guang An ◽

Lin Jiang ◽

Jin Hua Sun ◽

K.M. Liew

Keyword(s):

Mass Loss ◽

Flame Spread ◽

Loss Rate ◽

Mass Loss Rate ◽

High Elevation ◽

Flame Height ◽

Spread Rate ◽

Flame Spread Rate ◽

Sample Width ◽

Downward Flame Spread

An experimental study on downward flame spread over extruded polystyrene (XPS) foam at a high elevation is presented. The flame shape, flame height, mass loss rate and flame spread rate were measured. The influences of width and high altitude were investigated. The flame fronts are approximately horizontal. Both the intensity of flame pulsation and the average flame height increase with the rise of sample width. The flame spread rate first drops and then rises with an increase in width. The average flame height, mass loss rate and flame spread rate at the higher elevation is smaller than that at a low elevation, which demonstrates that the XPS fire risk at the higher elevation area is lower. The experimental results agree well with the theoretical analysis. This work is vital to the fire safety design of building energy conservation system.

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Radio Supernovae as Direct Evidence of Stellar Evolution in Real Time

Highlights of Astronomy ◽

10.1017/s1539299600021171 ◽

1998 ◽

Vol 11 (1) ◽

pp. 367-367

Author(s):

S.D. Van Dyk ◽

M.J. Montes ◽

K.W. Weiler ◽

R.A. Sramek ◽

N. Panagia

Keyword(s):

Mass Loss ◽

Stellar Evolution ◽

Loss Rate ◽

Direct Evidence ◽

Mass Loss Rate ◽

X Ray ◽

Stringent Constraint ◽

Clear Change ◽

Late Stages ◽

Circumstellar Environment

The radio emission from supernovae provides a direct probe of a supernova’s circumstellar environment, which presumably was established by mass-loss episodes in the late stages of the progenitor’s presupernova evolution. The observed synchrotron emission is generated by the SN shock interacting with the relatively high-density circumstellar medium which has been fully ionized and heated by the initial UV/X-ray flash. The study of radio supernovae therefore provides many clues to and constraints on stellar evolution. We will present the recent results on several cases, including SN 1980K, whose recent abrupt decline provides us with a stringent constraint on the progenitor’s initial mass; SN 1993J, for which the profile of the wind matter supports the picture of the progenitor’s evolution in an interacting binary system; and SN 1979C, where a clear change in presupernova mass-loss rate occurred about 104 years before explosion. Other examples, such as SNe 19941 and 1996cb, will also be discussed.

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