Sex-specific mass loss in chick-rearing South Polar Skuas Stercorarius maccormicki- stress induced or adaptive?

Various aspects such as development, experimentation, and analysis have been covered in the present work to examine the behavior of test coatings under slurry erosion. The primary objective of the present study was to establish the specific mass loss from the test coatings under various slurry environmental conditions and highlights the importance of the addition of alumina in improving the slurry erosion resistance of Ni-TiO2 coating. To attain this objective, two powder compositions, viz. Ni-20TiO2 and Ni-15TiO2-5Al2O3 were deposited onto the CA6NM grade hydro-turbine steel using high velocity frame spray process. The microstructural characterization of the coatings was done by employing surface roughness tester, scanning electron microscope/energy-dispersive X-ray spectroscopy, and X-ray diffraction techniques, whereas mechanical analysis was carried out using micro-hardness and bond strength tester. The slurry erosion tests were performed using an indigenously fabricated high speed slurry erosion test rig at different levels of rotational speed, average particle size of erodent, and slurry concentration in order to explore their effects on slurry erosion performance of test coatings. The slurry erosion results, as well as scanning electron microscope observations of eroded specimens, revealed higher slurry erosion resistance of Ni-15TiO2-5Al2O3 coating in comparison with Ni-20TiO2 coating. Furthermore, each operational parameter was found to have a proportional effect on specific mass loss in case of both the coatings.

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Effect of Environmental Conditions on the Dehydration and Performance of Fire-Protective Gels

Fire Technology ◽

10.1007/s10694-020-01045-2 ◽

2020 ◽

Author(s):

Jacob Kadel ◽

Faraz Hedayati ◽

Stephen L. Quarles ◽

Aixi Zhou

Keyword(s):

Relative Humidity ◽

Mass Loss ◽

Fire Performance ◽

Specific Mass ◽

Fire Front ◽

And Performance ◽

The Relationship ◽

High Winds ◽

Specific Mass Loss ◽

Better Than

Abstract During wildfire events fire-protective gels can be used as a line of defense to protect structures. The effectiveness of freshly applied gels in delaying ignition and flame growth on structures has been well established. However, in a real-world scenario there is a period between the application of the gel and the arrival of a spot fire or the fire-front. During this period, the gels are often exposed to extreme conditions consisting of high winds and low relative humidity. The effect of these weathering conditions on the performance of fire-protective gels is still poorly understood. This study examined the dehydration and performance of fire-protective gels following a range of weathering conditions. Two commercially available gels were applied to a 100-mm by 100-mm T1-11 plywood sample and then artificially weathered in an environmental chamber, with controlled temperature, relative humidity, and wind. The remaining mass of the gels was measured at selected intervals to determine the relationship between mass loss and dehydration related to weathering. A second series of tests was conducted on weathered T1-11 samples at specific mass loss states as well as on freshly applied gels using a 50 kW/m2 heat flux exposure utilizing a cone calorimeter. Results indicated that they dehydrated to the point where, after 3 h, fire performance was no better than the uncoated wood samples and the gels could facilitate ignition. This timeline suggests that gels should only be applied by first responders and homeowners should focus on evacuation related activities.

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Greenland high-elevation mass balance: inference and implication of reference period (1961–90) imbalance

Annals of Glaciology ◽

10.3189/2015aog70a967 ◽

2015 ◽

Vol 56 (70) ◽

pp. 105-117 ◽

Cited By ~ 21

Author(s):

William Colgan ◽

Jason E. Box ◽

Morten L. Andersen ◽

Xavier Fettweis ◽

Beáta Csathó ◽

...

Keyword(s):

Mass Loss ◽

Mass Balance ◽

Greenland Ice Sheet ◽

Mass Gain ◽

High Elevation ◽

Reference Period ◽

Input Output ◽

Specific Mass ◽

Ice Dynamics ◽

Dynamic Mass

AbstractWe revisit the input–output mass budget of the high-elevation region of the Greenland ice sheet evaluated by the Program for Arctic Regional Climate Assessment (PARCA). Our revised reference period (1961–90) mass balance of 54±48 Gt a–1 is substantially greater than the 0±21 Gt a–1 assessed by PARCA, but consistent with a recent, fully independent, input–output estimate of high-elevation mass balance (41±61 Gt a–1). Together these estimates infer a reference period high-elevation specific mass balance of 4.8±5.4 cm w.e. a–1. The probability density function (PDF) associated with this combined input–output estimate infers an 81% likelihood of high-elevation specific mass balance being positive (>0 cm w.e. a–1) during the reference period, and a 70% likelihood that specific balance was >2 cm w.e. a–1. Given that reference period accumulation is characteristic of centurial and millennial means, and that in situ mass-balance observations exhibit a dependence on surface slope rather than surface mass balance, we suggest that millennial-scale ice dynamics are the primary driver of subtle reference period high-elevation mass gain. Failure to acknowledge subtle reference period dynamic mass gain can result in underestimating recent dynamic mass loss by ~17%, and recent total Greenland mass loss by ~7%.

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Theory of winds from cool stars

Symposium - International Astronomical Union ◽

10.1017/s0074180900156591 ◽

1987 ◽

Vol 122 ◽

pp. 289-305

Author(s):

Thomas E. Holzer

Keyword(s):

Solar Wind ◽

Stellar Winds ◽

Late Type ◽

Physical Processes ◽

Specific Mass ◽

Low Gravity ◽

Cool Stars ◽

Astrophysical Flows ◽

Theoretical Considerations ◽

Specific Mass Loss

The goal of this paper is to provide a framework for thinking about the various physical processes that may play significant roles in driving the massive winds of cool, low-gravity stars. First, some general theoretical considerations involving mass, momentum, and energy balance are discussed. Next, the value of the solar wind as an analog for these late-type stellar winds and for related astrophysical flows is briefly examined. Finally, four specific mass-loss mechanisms are discussed, and the possible importance of each of these mechanisms for massive winds from cool, low-gravity stars is evaluated.

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Fire-resistant hydrophobic nanocoated composite partition sheets

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705718799814 ◽

2018 ◽

Vol 32 (11) ◽

pp. 1467-1484 ◽

Cited By ~ 1

Author(s):

BG Bavithran ◽

VA Nagarajan ◽

KP Vinod Kumar

Keyword(s):

Fumed Silica ◽

Loss Rate ◽

Low Cost ◽

Mass Loss Rate ◽

Constant Heat Flux ◽

Specific Mass ◽

Peak Heat Release Rate ◽

Polyester Matrix ◽

Specific Mass Loss ◽

Composite Samples

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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Water accumulation as a function of temperature on specimens in an electron microscope cold stage

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142219 ◽

1986 ◽

Vol 44 ◽

pp. 114-115 ◽

Cited By ~ 2

Author(s):

M.K. Lamvik ◽

D.A. Kopf ◽

S.D. Davilla ◽

J.D. Robertson

Keyword(s):

Electron Microscope ◽

Mass Loss ◽

Liquid Helium ◽

Liquid Nitrogen ◽

Liquid Nitrogen Temperature ◽

Liquid Helium Temperature ◽

Helium Temperature ◽

Cold Stage ◽

Water Accumulation ◽

Better Than

Last year we reported1 that there is a striking reduction in the rate of mass loss when a specimen is observed at liquid helium temperature. It is important to determine whether liquid helium temperature is significantly better than liquid nitrogen temperature. This requires a good understanding of mass loss effects in cold stages around 100K.

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Electron Beam-Induced Mass Loss in Freeze-Dried Tissue and Protein Samples

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010011917x ◽

1985 ◽

Vol 43 ◽

pp. 470-471

Author(s):

M.E. Cantino ◽

M.K. Goddard ◽

L.E. Wilkinson ◽

D.E. Johnson

Keyword(s):

Electron Beam ◽

Salivary Gland ◽

Mass Loss ◽

Counting Rate ◽

Dose Dependence ◽

X Ray ◽

Large Samples ◽

Freeze Dried ◽

Muscle Homogenate ◽

Large Muscle

Quantification in biological x-ray microanalysis depends on accurate evaluation of mass loss. Although several studies have addressed the problem of electron beam induced mass loss from organic samples (eg., 1,2). uncertainty persists as to the dose dependence, the extent of loss, the elemental constituents affected, and the variation in loss for different materials and tissues. in the work described here, we used x-ray counting rate changes to measure mass loss in albumin (used as a quantification standard), salivary gland, and muscle.In order to measure mass loss at low doses (10-4 coul/cm2 ) large samples were needed. While freeze-dried salivary gland sections of the required dimensions were available, muscle sections of this size were difficult to obtain. To simulate large muscle sections, frog or rat muscle homogenate was injected between formvar films which were then stretched over slot grids and freeze-dried. Albumin samples were prepared by a similar procedure. using a solution of bovine serum albumin in water. Samples were irradiated in the STEM mode of a JEOL 100C.

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Elemental mass loss in silicate minerals during x-ray analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100177155 ◽

1990 ◽

Vol 48 (4) ◽

pp. 804-805

Author(s):

P.E. Champness ◽

R.W. Devenish

Keyword(s):

Mass Loss ◽

Current Density ◽

Damage Mechanism ◽

Beam Current ◽

Single Chain ◽

Plagioclase Feldspar ◽

X Ray ◽

Alkali Ions ◽

Structural Order ◽

Sheet Silicate

It has long been recognised that silicates can suffer extensive beam damage in electron-beam instruments. The predominant damage mechanism is radiolysis. For instance, damage in quartz, SiO2, results in loss of structural order without mass loss whereas feldspars (framework silicates containing Ca, Na, K) suffer loss of structural order with accompanying mass loss. In the latter case, the alkali ions, particularly Na, are found to migrate away from the area of the beam. The aim of the present study was to investigate the loss of various elements from the common silicate structures during electron irradiation at 100 kV over a range of current densities of 104 - 109 A m−2. (The current density is defined in terms of 50% of total current in the FWHM probe). The silicates so far ivestigated are:- olivine [(Mg, Fe)SiO4], a structure that has isolated Si-O tetrahedra, garnet [(Mg, Ca, Fe)3Al2Si3AO12 another silicate with isolated tetrahedra, pyroxene [-Ca(Mg, Fe)Si2O6 a single-chain silicate; mica [margarite, -Ca2Al4Si4Al4O2O(OH)4], a sheet silicate, and plagioclase feldspar [-NaCaAl3Si5O16]. Ion- thinned samples of each mineral were examined in a VG Microscopes UHV HB501 field- emission STEM. The beam current used was typically - 0.5 nA and the current density was varied by defocussing the electron probe. Energy-dispersive X-ray spectra were collected every 10 seconds for a total of 200 seconds using a Link Systems windowless detector. The thickness of the samples in the area of analysis was normally 50-150 nm.

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