MPV-Q view of vorticity development in a saturated atmosphere

AbstractThe hydration of an outer layer on nuclear waste glasses is known to occur during leaching, but the actual speciation of hydrogen (as water or hydroxyl groups) in these layers has not been determined. As part of the Nevada Nuclear Waste Storage Investigations Project, we have used infrared spectroscopy to determine hydrogen speciations in three nuclear waste glass compositions (SRL-131 & 165, and PNL 76-68), which were leached at 90°C (all glasses) or hydrated in a vapor-saturated atmosphere at 202°C (SRL-131 only). Hydroxyl groups were found in the surface layers of all the glasses. In addition, molecular water was found in the surface of SRL-131 and PNL 76-68 glasses that had been leached for several months in deionized water, and in the vapor-hydrated sample. The water/hydroxyl ratio increases with increasing reaction time; molecular water makes up most of the hydrogen in the thick reaction layers on vapor-phase hydrated glass while only hydroxyl occurs in the least reacted samples. Using the known molar absorptivities of water and hydroxyl in silica-rich glass the vapor-phase layer contained 4.8 moles/liter of molecular water, and 0.6 moles water in the form hydroxyl. A 15 micrometer layer on SRL-131 glass formed by leaching at 90°C contained a total of 4.9 moles/liter of water, 2/3 of which was as hydroxyl. The unreacted bulk glass contains about 0.018 moles/liter water, all as hydroxyl.The amount of hydrogen added to the SRL-131 glass was about 70% of the original Na + Li content, not the 300% that would result from alkali-hydronium ion (H30+) interdiffusion. If all the hydrogen is then assumed to be added as the result of alkali-H+ interdiffusion, the molecular water observed may have formed from condensation of the original hydroxyl groups according to:20H = H20 molecular + 00where 00 refers to a bridging oxygen, and OH refers to a hydroxyl group attached to a silicate polymer. The hydrated layer on the nuclear waste glasses appears to be of relatively low water content (4 to 7% by weight) and is not substantially hydroxylated. Thus, these layers do not have many of the properties associated with “gel” layers.

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Effect of Olive-Pine Bottom Ash on Properties of Geopolymers Based on Metakaolin

10.20944/preprints201912.0214.v1 ◽

2019 ◽

Author(s):

Eduardo Bonet-Martínez ◽

Pedro García-Cobo ◽

Luis Pérez-Villarejo ◽

Eulogio Castro ◽

Dolores Eliche-Quesada

Keyword(s):

Room Temperature ◽

Bottom Ash ◽

Raw Material ◽

Climatic Chamber ◽

General Terms ◽

Saturated Atmosphere ◽

Naoh Solution ◽

Alkaline Activator ◽

Water Saturated ◽

Potential Use

In this research, the feasibility of using bottom ashes generated by the combustion of biomass (olive pruning and pine pruning) as a source of aluminosilicates (OPBA) has been studied, replacing the metakaolin precursor (MK) in different proportions (0, 25, 50, 75 and 100 wt. % substitution) for the synthesis of geopolymers. As alkaline activator an 8 M NaOH solution and a Na2SiO3 have been used. The geopolymers were cured 24 hours in a climatic chamber at 60 ° C in a water-saturated atmosphere, subsequently demoulded and cured at room temperature for 28 days. The results indicated that the incorporation of OPBA waste, which have 19.7 wt. % of Ca, modifies the characteristics of the products formed after alkaline activation. In general terms, the incorporation of increasing amounts of calcium-rich ashes results in geopolymers with higher bulk density. The compressive strength increases with the addition of up to 50 wt. % of OPBA with respect to the control geopolymers, contributing the composition of the residue to the acquisition of a better behaviour mechanical. The results indicate the potential use of these OPBA waste as raw material to produce unconventional cements with 28-day curing strengths greater than 10 MPa, and thermal conductivities less than 0.35 W/mK.

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Effect heat stress on subcellular localization of Ca2+ in tomato fruits

Acta Societatis Botanicorum Poloniae ◽

10.5586/asbp.1998.028 ◽

2014 ◽

Vol 67 (3-4) ◽

pp. 235-241 ◽

Cited By ~ 1

Author(s):

Grażyna Garbaczewska ◽

Danuta Chołuj ◽

Zofia Starck

Keyword(s):

Heat Stress ◽

Subcellular Localization ◽

Calcium Content ◽

Cell Ultrastructure ◽

Water Soluble ◽

Tomato Fruits ◽

Temperature Regimes ◽

Saturated Atmosphere ◽

Experimental Treatments ◽

Soluble Fractions

The aim of this paper was to compare the fruit cell ultrastructure and subcellular localization of Ca2+ after heat stress with the use of the potassium antimonate method (Slocum and Roux 1982, Tretyn et al. 1992). The tomato plants Robin cv., relatively tolerant to heat stress, were grown under uncontrolled greenhouse conditions to the stage of fruiting. The plants were placed for 20h in two temperature regimes: 23oC (optimal temperature) or 40oC (heat stress) in darkness, under water vapour saturated atmosphere. Immediately after heat stress the fruits were harvested to estimate water soluble and insoluble calcium contents and subcellular localization of Ca2+. After heating the concentration of calcium in tomato fruits increased about twice. In both temperature treatments the water soluble fractions were lower than insoluble ones at smaller differences between insoluble and soluble fractions after heat stress. The shapes and localization of Ca2+ detected with the use of potassium antimonate method show that in fruits of control plants the precipitates were numerous, small and of oval shape. They were dispersed in cytosol or adjoined to endoplasmic reticulum or to external membrane of chloroplast. In the fruit of heated plants the precipitates were irregular in shape, amorphous and singly dispersed in the cytosol. We observed also some cytological changes in the structure of membranes and organelles of the plants of both experimental treatments. The heat induced increase of calcium content and the changes in subcellular localization of Ca2+ under heat stress suggest that calcium ions may be involved in avoiding heat injury. The problem requires more detailed further investigations.

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Histological and Biochemical Observations of Developing Enameloid of the Sea Bream

Advances in Dental Research ◽

10.1177/08959374870010020701 ◽

1987 ◽

Vol 1 (2) ◽

pp. 191-195 ◽

Cited By ~ 14

Author(s):

K. Kawasaki ◽

S. Shimoda ◽

M. Fukae

Keyword(s):

Proteolytic Activity ◽

Developmental Stages ◽

Proteolytic Enzymes ◽

Sea Bream ◽

Total Protein Content ◽

Noncollagenous Proteins ◽

Saturated Atmosphere ◽

Tooth Germs ◽

Water Saturated ◽

Cryostat Sections

In order to study changes in the enameloid matrix of the Sea Bream during the course of its development, we selected the developmental tooth germs of this fish as representative of three different developmental stages: "chalk-like", "cheese-like", and "soft" enameloid. The protein, calcium, and phosphate contents of each sample were analyzed. The changes of the total protein content in each sample suggest that a major part of the proteins decreased during maturation, although newly formed enameloid of the Sea Bream contains collagen and noncollagenous proteins. The existence of proteolytic activity was examined by placement of undemineralized cryostat sections of unfixed tooth germs on exposed and processed photographic films and then incubation for 30 min in a water-saturated atmosphere at 37°C. Proteolytic activity could be detected in the enameloid matrix, which appeared to be in a "cheese-like" stage. It is suggested that proteolytic enzymes play an important role in the removal of proteins during the maturation of enameloid, although the detailed mechanism of the process is still obscure.

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Precipitable water characteristics during the 2013 Colorado flood using ground-based GPS measurements

Atmospheric Measurement Techniques ◽

10.5194/amt-10-4055-2017 ◽

2017 ◽

Vol 10 (11) ◽

pp. 4055-4066 ◽

Cited By ~ 5

Author(s):

Hannah K. Huelsing ◽

Junhong Wang ◽

Carl Mears ◽

John J. Braun

Keyword(s):

United States ◽

Moisture Transport ◽

Large Scale ◽

Precipitable Water ◽

Tropical Eastern Pacific ◽

Public And Private ◽

Maximum Rainfall ◽

Water Characteristics ◽

Synoptic Features ◽

Saturated Atmosphere

Abstract. During 9–16 September 2013, the Front Range region of Colorado experienced heavy rainfall that resulted in severe flooding. Precipitation totals for the event exceeded 450 mm, damages to public and private properties were estimated to be over USD 2 billion, and nine lives were lost. This study analyzes the characteristics of precipitable water (PW) surrounding the event using 10 years of high-resolution GPS PW data in Boulder, Colorado, which was located within the region of maximum rainfall. PW in Boulder is dominated by seasonal variability with an average summertime maximum of 36 mm. In 2013, the seasonal PW maximum extended into early September and the September monthly mean PW exceeded the 99th percentile of climatology with a value 25 % higher than the 40-year climatology. Prior to the flood, around 18:00 UTC on 8 September, PW rapidly increased from 22 to 32 mm and remained around 30 mm for the entire event as a result of the nearly saturated atmosphere. The frequency distribution of September PW for Boulder is typically normal, but in 2013 the distribution was bimodal due to a combination of above-average PW values from 1 to 15 September and much drier conditions from 16 to 30 September. The above-normal, near-saturation PW values during the flood were the result of large-scale moisture transport into Colorado from the Tropical Eastern Pacific and the Gulf of Mexico. This moisture transport was the product of a stagnating cutoff low over the southwestern United States working in conjunction with an anticyclone located over the southeastern United States. A blocking ridge located over the Canadian Rocky Mountains kept both of the synoptic features in place over the course of several days, which helped to provide continuous moisture to the storm, thus enhancing the accumulated precipitation totals.

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Morphology and properties of silica/novolac hybrid xerogels synthesized using sol–gel polymerization at solvent vapor-saturated atmosphere

Materials & Design (1980-2015) ◽

10.1016/j.matdes.2014.12.046 ◽

2015 ◽

Vol 69 ◽

pp. 190-196 ◽

Cited By ~ 16

Author(s):

Mohamad Mehdi Seraji ◽

Azadeh Seifi ◽

Ahmad Reza Bahramian

Keyword(s):

Sol Gel ◽

Solvent Vapor ◽

Saturated Atmosphere ◽

Hybrid Xerogels

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The effects of priming on seed longevity in Ranunculus sceleratus L.

Seed Science Research ◽

10.1017/s0960258500000969 ◽

1991 ◽

Vol 1 (4) ◽

pp. 243-249 ◽

Cited By ~ 23

Author(s):

R. J. Probert ◽

S. V. Bogh ◽

A. J. Smith ◽

G. E. Wechsberg

Keyword(s):

Moisture Content ◽

Seed Quality ◽

Ecological Factors ◽

Fold Increase ◽

Seed Longevity ◽

Distilled Water ◽

Survival Curves ◽

Saturated Atmosphere ◽

Equilibrium Relative Humidity ◽

Species Specific

AbstractPriming in polyethylene glycol (PEG, −1.5 MPa) for 7 d followed by drying, led to a 4–5 fold increase in mean longevity when achenes (seeds) of Ranunculus sceleratus L. were subsequently stored at 35°C and 9.2% moisture content on a fresh weight basis (67.1% equilibrium relative humidity). The increase in longevity was due to an increase in the standard deviation of the frequency distribution of individual seed lifespans (decrease in the slope of transformed survival curves) and to a lesser extent to an increase in the intercept of survival curves. Priming for 1 d resulted in a smaller but significant increase in longevity independent of whether seeds were primed in PEG, distilled water or a saturated atmosphere (100% RH).The effects of priming were not due to the prevention of imbibition injury, and there was no evidence that the water relations of whole achenes was affected by priming. The effects of a 7 d priming treatment were dependent on the temperature and nature of the priming medium. However, no differences were recorded between corresponding treatments which were primed in PEG or distilled water. Moreover, the survival and responsivity to priming of R. sceleratus seeds was not related to dormancy status. The effects of priming on the longevity of R. sceleratus seeds are apparently unrelated to seed quality as the response of seeds previously aged for 8 d at 35°C and 7.9% moisture content was similar to that for unaged seeds.Priming followed by drying did not increase seed longevity in the related species R. acris L. The promotive effects of priming on seed survival appear to be species specific and may be related to ecological factors.

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Factors affecting the production of resting spores by Zoophthora radicans in the spotted alfalfa aphid, Therioaphis trifolii f. maculata

Canadian Journal of Botany ◽

10.1139/b89-114 ◽

1989 ◽

Vol 67 (3) ◽

pp. 848-855 ◽

Cited By ~ 20

Author(s):

Travis R. Glare ◽

Richard J. Milner ◽

Graham A. Chilvers

Keyword(s):

Indirect Evidence ◽

Spore Production ◽

Factors Affecting ◽

Resting Spore ◽

Solid Media ◽

Number Of Factors ◽

Resting Spores ◽

Saturated Atmosphere ◽

Zoophthora Radicans ◽

Genetic Combination

Resting spore production by Zoophthora radicans (Brefeld) Batko in infected cadavers of the spotted alfalfa aphid, Therioaphis trifolii (Monell) f. maculata, varied according to a number of factors. For four isolates of the fungus tested, the proportion of cadavers containing resting spores was consistently greater at 10 °C than at higher temperatures. At 20 °C, a saturated atmosphere (100% RH) favoured resting spore production, and the proportion of infected cadavers that contained resting spores was nearly twice the amount of that at 95% RH. Individual isolates of the fungus were found to differ in their ability to form resting spores in infected cadavers; some formed resting spores in few or no cadavers, whereas others formed resting spores in many, under similar conditions. The ability to produce resting spores sometimes varied following serial culturing on solid media. Interestingly, resting spore production was found to correlate with inoculum density. Also, inoculation of aphids with two fungal isolates resulted in a marked increase in resting spore production compared with that of either isolate alone. It is presumed that some form of genetic combination is involved. Indirect evidence suggests that this is more likely to be cytoplasmic than nuclear in origin.

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Effect of Olive-Pine Bottom Ash on Properties of Geopolymers Based on Metakaolin

Materials ◽

10.3390/ma13040901 ◽

2020 ◽

Vol 13 (4) ◽

pp. 901

Author(s):

Eduardo Bonet-Martínez ◽

Pedro García-Cobo ◽

Luis Pérez-Villarejo ◽

Eulogio Castro ◽

Dolores Eliche-Quesada

Keyword(s):

Room Temperature ◽

Bottom Ash ◽

Raw Material ◽

Climatic Chamber ◽

General Terms ◽

Saturated Atmosphere ◽

Naoh Solution ◽

Alkaline Activator ◽

Water Saturated ◽

Potential Use

In this research, the feasibility of using bottom ashes generated by the combustion of biomass (olive pruning and pine pruning) as a source of aluminosilicates (OPBA) has been studied, replacing the metakaolin precursor (MK) in different proportions (0, 25, 50, 75, and 100 wt.% substitution) for the synthesis of geopolymers. As alkaline activator an 8 M NaOH solution and a Na2SiO3 have been used. The geopolymers were cured 24 h in a climatic chamber at 60 °C in a water-saturated atmosphere, subsequently demoulded and cured at room temperature for 28 days. The results indicated that the incorporation of OPBA waste, which have 19.7 wt.% of Ca, modifies the characteristics of the products formed after alkaline activation. In general terms, the incorporation of increasing amounts of calcium-rich ashes results in geopolymers with higher bulk density. The compressive strength increases with the addition of up to 50 wt.% of OPBA with respect to the control geopolymers, contributing the composition of the residue to the acquisition of better mechanical behavior. The results indicate the potential use of these OPBA waste as raw material to produce unconventional cements with 28-day curing strengths greater than 10 MPa, and thermal conductivities less than 0.35 W/mK.

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Internal Gravity Waves in a Saturated Moist Neutral Atmosphere

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-13-051.1 ◽

2013 ◽

Vol 70 (12) ◽

pp. 3693-3709 ◽

Cited By ~ 2

Author(s):

David J. Muraki ◽

Richard Rotunno

Keyword(s):

Numerical Solutions ◽

Internal Gravity Waves ◽

Analytic Solutions ◽

Neutral Atmosphere ◽

Atmospheric Flow ◽

Start Up ◽

Exact Analytic Solutions ◽

Downward Displacement ◽

Neutral Flow ◽

Saturated Atmosphere

Abstract This work is motivated by an unusual feature associated with the start-up of a moist nearly neutral atmospheric flow over a mountain ridge that was previously observed in a full-physics numerical model. In that study, the upstream propagation of a wave of subsidence precluded the establishment of upward-displaced and saturated flow that might be expected upstream of the topography. This phenomenon was hypothesized to be a consequence of the peculiar property of saturated moist neutral flow: an upward air parcel displacement produces zero buoyancy, while a downward displacement desaturates the air parcel and produces a positive buoyancy anomaly. In the present study, this hypothesis is confirmed within numerical solutions to a reduced system of equations that incorporates the saturated-atmosphere property in a particularly simple manner. The relatively uncomplicated nature of these solutions motivates the numerical solution of a further simplified initial-value problem for both nonhydrostatic and hydrostatic flow. Exact analytic solutions are developed for the latter hydrostatic case, which explains the upstream-propagating wave of subsidence as a shock phenomenon.

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