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1
Callahan, Ann M., Chris Dardick, and Ralph Scorza. "Characterization of ‘Stoneless’: A Naturally Occurring, Partially Stoneless Plum Cultivar." Journal of the American Society for Horticultural Science 134, no. 1 (2009): 120–25. http://dx.doi.org/10.21273/jashs.134.1.120.
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The plum (Prunus domestica) cultivar Stoneless was characterized to determine if the lack of stone was the result of reduced endocarp development or a decrease in lignification. Fruit were sampled at several times from 37 days before stone hardening (DBH) until the stone was too hard to cut with a knife and were compared with plum fruit that had normal stones. At all sampling times there was less endocarp tissue and reduced lignin staining in the ‘Stoneless’ plum fruit. The tissue that did stain appeared to be small endocarp remnants present in the ‘Stoneless’ plum, and was concentrated at the suture side and at the blossom end as well as the stem end. The lignin stain was detected in these regions beginning at 19 DBH, while the normal plums had a progression of staining beginning at the blossom end, suture side at 23 DBH and radiating up to the stem end and throughout the presumptive stone tissue at 8 DBH. Comparison of dry weight for dissected tissues agreed with the specific lack of endocarp tissue in the ‘Stoneless’ plum. Gene activity for the lignin pathway was analyzed using four known genes required for lignification. All four genes showed endocarp-specific expression in ‘Stoneless’ similar to that observed for the control. These results support the idea that the phenotype of ‘Stoneless’ plum fruit is due to a decrease in endocarp formation rather than a decrease in endocarp lignification.
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Knoche, Moritz, Eckhard Grimm, Andreas Winkler, Merianne Alkio, and Jürgen Lorenz. "Characterizing Neck Shrivel in European Plum." Journal of the American Society for Horticultural Science 144, no. 1 (2019): 38–44. http://dx.doi.org/10.21273/jashs04561-18.
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Neck shrivel is a physiological disorder of european plum (Prunus ×domestica L.) fruit, characterized by a shriveled pedicel end and a turgescent stylar end. Affected fruit are perceived as of poor quality. Little is known of the mechanistic basis of neck shrivel, but microcracking of the cuticle has been implicated. The objective of our study was to quantify transpiration through the skin surfaces of european plums with and without symptoms of neck shrivel. Cumulative transpiration increased linearly with time and was greater in the susceptible european plum cultivar Hauszwetsche Wolff with neck shrivel, compared with fruit of the same cultivar but without neck shrivel and compared with fruit of the nonsusceptible unnamed clone P5-112. Cumulative transpiration of epidermal skin segments (ES) excised from symptomatic ‘Hauszwetsche Wolff’ from near the pedicel end exceeded that from ES excised from near the stylar end. The permeance of ES from near the pedicel end of ‘Hauszwetsche Wolff’ with neck shrivel (12.4 ± 2.6 × 10−4 m·s−1) exceeded that of ES from near the stylar end (2.9 ± 0.4 × 10−4 m·s−1) 4.3-fold. However, in the clone P5-112, the same difference was only 1.6-fold (1.3 ± 0.8 × 10−4 m·s−1 vs. 0.8 ± 0.3 × 10−4 m·s−1). Microscopy revealed numerous microcracks near the pedicel end of symptomatic ‘Hauszwetsche Wolff’ fruit but markedly fewer microcracks near the stylar end. The microcracks near the pedicel end were oriented parallel to the pedicel/style axis, whereas those near the stylar end were randomly oriented. Juices extracted from near the pedicel end of susceptible cultivars had consistently more negative osmotic potentials [ψS (e.g., for Doppelte Hauszwetsche −5.1 ± 0.1 MPa)] than those from near the stylar end (e.g., for Doppelte Hauszwetsche −4.0 ± 0.1 MPa) or that from fruit without symptoms of neck shrivel (e.g., for pedicel end and stylar scar regions of Doppelte Hauszwetsche −3.8 ± 0.1 vs. −3.3 ± 0.1 MPa, respectively). Our results indicate that increased transpiration through microcracks near the pedicel end may contribute to neck shrivel but that the causes of neck shrivel are likely more complex.
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Guerra, M., M. A. Sanz, and P. A. Casquero. "Influence of Harvest Dates on Quality, Storage Capacity and Sensory Attributes of European Plum cv. Green Gage." Food Science and Technology International 15, no. 6 (2009): 527–34. http://dx.doi.org/10.1177/1082013209350537.
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The aim of this work was to determine storage capacity and changes in quality and consumer acceptance in plum harvested at different dates as well as to determine which instrumental parameters show good correlation with consumer acceptance and sensory properties. Both harvest date and storage time played a significant role in quality and sensory characteristics. Incidence of internal breakdown (IB) was significantly higher in fruit harvested last and increased significantly until the end of storage. Market life of ‘Green Gage’ plum varies from 20 days in fruit harvested on the last harvest date to 40 days in fruit harvested on earlier dates. When storage is needed, firmness, the best harvest index, should be higher than 42 N in order to extend market life and prevent IB damages in ‘Green Gage’ plums. However, fruit from early harvest dates has a lower consumer acceptance than fruit from late harvest dates (low TSS:TA). Thus, a minimum quality threshold based on TSS:TA (18.9) has been established over which consumer liking for European plums cv. Green Gage improves significantly. High linear regression between a* and TSS:TA would allow to use the a* color parameter as a nondestructive measurement to estimate consumer acceptance.
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Januszek, Magdalena, and Paweł Satora. "How Different Fermentation Type Affects Volatile Composition of Plum Jerkums." Applied Sciences 11, no. 10 (2021): 4658. http://dx.doi.org/10.3390/app11104658.
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Quality of plum jerkum is significantly associated to the profile of volatile compounds. Therefore, we decided to assess the impact of various fermentation types on selected properties of plum jerkums, especially compounds which contribute to the aroma of the finished product. We used the following yeast strains: S. cerevisiae S1, H. uvarum H2, and Ethanol RED (S. cerevisiae). Moreover, we considered spontaneous fermentation. S. cerevisiae and H. uvarum strains were isolated during the fermentation of Čačanska Lepotica or Węgierka Dąbrowicka (plum cultivars), respectively. As for fermentation type, spontaneous fermentation of H. uvarum H2 provided the best results. It could be associated to the fact that plum juices fermented with H. uvarum H2 presented the highest concentration of terpenoids, esters, or some higher alcohols. In the current paper, application of indigenous strains of yeasts resulted in the required oenological characteristics, e.g., highest fermentation efficiency and concentration of ethanol was determined in juices fermented with Ethanol RED (S. cerevisiae) and also with S. cerevisiae S1. Our results suggested that indigenous strains of yeasts present in plums demonstrate great potential for the production of plum jerkums of high quality.
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Mao, Samuel S., and Xiaojun Zhang. "High-Throughput Multi-Plume Pulsed-Laser Deposition for Materials Exploration and Optimization." Engineering 1, no. 3 (2015): 367–71. http://dx.doi.org/10.15302/j-eng-2015065.
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Gunaydin, Sule, Hakan Karaca, Lluís Palou, Beatriz de la Fuente, and María B. Pérez-Gago. "Effect of Hydroxypropyl Methylcellulose-Beeswax Composite Edible Coatings Formulated with or without Antifungal Agents on Physicochemical Properties of Plums during Cold Storage." Journal of Food Quality 2017 (2017): 1–9. http://dx.doi.org/10.1155/2017/8573549.
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The influence of hydroxypropyl methylcellulose- (HPMC-) beeswax (BW) composite edible coatings formulated with or without food additives with antifungal properties on physicochemical and sensory properties of plums(Prunus salicina)cv. “Friar” stored for 11 and 22 d at 1°C followed by a shelf life period of 5 d at 20°C was evaluated. Food preservatives selected from previous research included potassium sorbate (PS), sodium methyl paraben (SMP), and sodium ethyl paraben (SEP). Emulsions had 7% of total solid content and were prepared with glycerol and stearic acid as plasticizer and emulsifier, respectively. All the coatings reduced plum weight and firmness loss and coated fruit showed higher titratable acidity, soluble solids content, and hue angle values at the end of the storage period. In addition, physiological disorders such as flesh browning and bleeding were reduced in coated samples compared to uncoated controls. Paraben-based coatings were the most effective in controlling weight loss and the SMP-based coating was the most effective in maintaining plum firmness. Respiration rate, sensory flavor, off-flavors, and fruit appearance were not adversely affected by the application of antifungal coatings. Overall, these results demonstrated the potential of selected edible coatings containing antifungal food additives to extend the postharvest life of plums, although further studies should focus on improving some properties of the coatings to enhance gas barrier properties and further increase storability.
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Liu, Weisheng, Dongcheng Liu, Aimin Zhang, et al. "Genetic Diversity and Phylogenetic Relationships among Plum Germplasm Resources in China Assessed with Inter-simple Sequence Repeat Markers." Journal of the American Society for Horticultural Science 132, no. 5 (2007): 619–28. http://dx.doi.org/10.21273/jashs.132.5.619.
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Inter-simple sequence repeat (ISSR) markers were used to evaluate genetic similarity and interrelationship among 104 plum (Prunus L. spp.) and related accessions from the Chinese National Germplasm Repository for Plums and Apricots and the Tianshan Germplasm Repository for Wild Fruit Resources, including six plum species (Prunus salicina Lindl., Prunus simonii Carr., Prunus ussuriensis Kov. et Kost., Prunus domestica L., Prunus cerasifera Ehrh., and Prunus spinosa L.), two related species [apricot (Prunus armeniaca L.) and nanking cherry (Prunus tomentosa Thunb.)], eight putative hybrids between plum and apricot (plumcot), and six accessions of wild European plum (P. domestica). Out of the 42 ISSR primers, 12 were selected, which generated 103 markers in total, 99 of which were polymorphic. Possible accession-specific ISSR bands or patterns were also found. Some possible synonyms or homonyms were clarified or discussed, and closely related accessions such as bud mutants were discriminated. Based on the unweighted pair group method with arithmetic mean (UPGMA) analysis and principal coordinate analysis (PCoA) using the Jaccard coefficient, two different dendrograms were constructed—one including accessions grouped by species and one with all 104 accessions—and a two-dimensional plot was obtained. Three groups were formed in both dendrograms and PCoA plot: Group I including apricot (‘Yinxiangbai’) and plumcot types; Group II containing Asia-originated diploid species [e.g., P. cerasifera, P. ussuriensis, P. tomentosa, and Chinese plum-types (i.e., P. salicina and its hybrids)]; and Group III involving European-origin polyploid species (e.g., P. spinosa and P. domestica) and recently found wild European plum accessions in China. The dendrogram with accessions grouped by species implied that 1) plumcot types had closer relatedness with apricot than with plum; 2) P. simonii should be a variant of P. salicina while P. ussuriensis an independent species; 3) P. domestica was more closely related to P. spinosa than to P. cerasifera. Two accessions of European plum (‘89-7-3’ and ‘Wanhei’) were clustered into outgroups in the dendrogram with all 104 accessions, which could been grouped within Group III in the PCoA plot. The distribution of both European plum and Chinese plum-types across respective groups did not reflect the geographic origins. The present study also further confirmed that the wild plants found in Xinjiang of China were P. domestica.
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Wolf, Jan, Ivo Ondrášek, and Tomáš Nečas. "Potential Use of Spring Budding Techniques in Production of Plum Nursery Trees." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 73, no. 3 (2019): 220–25. http://dx.doi.org/10.2478/prolas-2019-0035.
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Abstract The main objective of this work was to verify the possibility of shortening the time needed to produce nursery trees of plums, in view of the economic profitability in nursery production. To achieve this goal, rootstocks Citation®, Ishtara®, Penta®, Torinel®, Pumiselekt and St. Julien (from Wädenswil) were chip budded in the springtime with ‘Shiro’, ‘Angeleno’®, ‘Black Amber’, SLE2014/1, ‘Fertility’ (Asian type plums) and ‘Stanley’ (European type plum) as a control. At the end of the vegetation period, height (from the grafting position), trunk diameter above the place of budding and the number of shoots was recorded for each tree. The Penta® rootstock was evaluated as the most efficient, while ‘Shiro’ variety was evaluated as the most suitable variety. The best variety/rootstock combination was the combination of ‘Shiro’ on Ishtara® rootstock, where 100% of the budded trees reached an average height of 33.0 ± 3.6 cm. The highest trees of an average of 68.3 ± 4.6 cm were recorded for the combination of SLE2014/1 on Torinel® root-stock.
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Aleksei, Grunin, Maksimova Ksenia, and Goikhman Aleksander. "The features of Ni2MnIn polycrystalline Heusler alloy thin films formation by pulsed laser deposition." Open Engineering 11, no. 1 (2020): 227–32. http://dx.doi.org/10.1515/eng-2021-0019.
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AbstractThe Ni-Mn-In-based Heusler alloys belong to the most studied intermetallic compounds due to a variety of physical effects inherent to them, including the shape memory and magnetocaloric effect, field-induced structural phase transition, and others. All of these properties are strongly depend on element concentrations, uniformity, and purity of the structure. Therefore, rather strict requirements are imposed on the synthesis technology of such samples.We report the dependencies of Ni-Mn-In polycrystalline thin film composition on growth parameters. It was shown that the composition mismatch between sample and target caused by the resputtering of the sample material with high-energy particles of the ablation plume, and the different ablation yields of elements from the target. The main deposition parameters demonstrated (Ar growth pressure, laser energies, substrate temperature and annealing, target-to-sample distance) for the co-deposition process to obtain the Ni-Mn-In Heusler alloy polycrystalline thin films with the martensitic transition.
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Kuo, Ping-Hui, Ching-I. Lin, Yue-Hwa Chen, Wan-Chun Chiu, and Shyh-Hsiang Lin. "A high-cholesterol diet enriched with polyphenols from Oriental plums (Prunus salicina) improves cognitive function and lowers brain cholesterol levels and neurodegenerative-related protein expression in mice." British Journal of Nutrition 113, no. 10 (2015): 1550–57. http://dx.doi.org/10.1017/s0007114515000732.
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Ageing accompanied by a decline in cognitive performance may be a result of the long-term effects of oxidative stress on neurologic processes. It has been shown that high-cholesterol contents in the blood and brain may lead to the deposition of the β-amyloid (Aβ) protein in the brain, which damages brain cells. The present study was designed to observe the effect of polyphenol-rich Oriental plums on cognitive function and cerebral neurodegeneration-related protein expression in mice that were fed a high-cholesterol diet for 5 months. The study consisted of four groups: the control (Ctrl) group, which was fed the American Institute of Nutrition (AIN)-93M diet; the high cholesterol (HC) group, which was fed the AIN-93M diet with 5 % cholesterol; the high cholesterol+low Oriental plum (LOP) group, which was fed the AIN-93M diet with 5 % cholesterol and 2 % Oriental plum powder; and the high cholesterol+high Oriental plum (HOP) group, which was fed the AIN-93M diet with 5 % cholesterol and 5 % Oriental plum powder. Measurements of cognitive function were assessed using the Morris water maze, and the mRNA expression of cholesterol hydroxylase (Cyp46), Aβ and β-secretase 1 (BACE1) were analysed. The results showed that cholesterol concentrations in both the blood and the brain were significantly higher in the HC group than in the Ctrl and HOP groups at the end of the trial. The high-cholesterol diet per se produced significant cognitive deficits, which were accompanied by a significantly increased mRNA expression of Cyp46, BACE1, Aβ and 24-hydroxycholesterol in the brain cortex and hippocampus. However, all of these variables were non-significantly increased in the HOP group as compared to the Ctrl group. In conclusion, incorporating polyphenol-enriched Oriental plum into a high-cholesterol diet can ameliorate some of the symptoms of neurodegenerative conditions.
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Ghori, S. G., J. P. Heller, and A. K. Singh. "An efficient model for computing plume concentration in aquifers." Environmetrics 3, no. 2 (1992): 149–67. http://dx.doi.org/10.1002/env.3170030202.
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Leskey, Tracy C., Torri J. Hancock, and Starker E. Wright. "Host-tree-related differences in trap captures and electroantennogram activity of Conotrachelus nenuphar (Coleoptera: Curculionidae)." Canadian Entomologist 142, no. 3 (2010): 284–93. http://dx.doi.org/10.4039/n09-074.
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AbstractThe plum curculio, Conotrachelus nenuphar (Herbst), is a serious pest of stone and pome fruits (Rosaceae) in eastern North America. We recorded captures of adult plum curculios in the field and measured electroantennogram (EAG) activity in the laboratory associated with cultivars of four hosts, ‘Formosa’ Japanese plum (Prunus salicina Lindl.), ‘Stanley’ European plum (P. domestica L.), ‘Empire’ apple (Malus domestica Borkh.), and ‘Loring’ peach (P. persica (L.) Batsch) (Rosaceae) to determine whether hosts that may be attractive to the plum curculio under field conditions also elicit positive EAG responses. Trap captures of adults on ‘Formosa’ plum were significantly greater than on any other host, and corresponding headspace extracts also produced strong EAG responses throughout the active season. ‘Stanley’ plum and ‘Loring’ peach, the other stone-fruit hosts included in the study, elicited strong EAG responses throughout the season, although trap captures associated with these hosts were generally not as high as for ‘Formosa’ plum. Throughout the season, trap captures of adults were significantly lower for ‘Empire’ apple than for ‘Formosa’ plum, and EAG responses were much lower than for all stone-fruit hosts. Our results indicate that volatiles from ‘Formosa’ plum likely contain uniquecompounds or are comprised of ratios of stimulating compounds that make it much more attractive to plum curculio in the field.
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Muminova, Rano Dalabayevna, and Muyassar Ismailovna Tadjiyeva. "Sucking Pest Fruit Crops - Brown Fruit Mite (Bryobia Redikorzevi Reck)." American Journal of Agriculture and Biomedical Engineering 03, no. 05 (2021): 45–48. http://dx.doi.org/10.37547/tajabe/volume03issue05-09.
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It damages the apple tree, sweet cherry, peach, plum, cherry plum, pear and almond. Hibernates in the egg phase on the bark of shoots and branches, in forks. Hatching of larvae is observed at the end of the blooming of the apple tree. The released larvae feed on budding buds, young leaves. Then go to the shoots, branches. Similar transitions are observed in protononym and deutonymph, which turns into an adult. The development of the tick from larva to adult female is 30 days.
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Spisak, April. "After the End by Amy Plum." Bulletin of the Center for Children's Books 67, no. 11 (2014): 590. http://dx.doi.org/10.1353/bcc.2014.0529.
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Ojie, Oseikhuemen Osemekhian Davis, Reza Saatchi, and Mahdieh Saatchi. "Demonstration of the Effect of Centre of Mass Height on Postural Sway Using Accelerometry for Balance Analysis." Technologies 8, no. 2 (2020): 20. http://dx.doi.org/10.3390/technologies8020020.
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The effect of center of mass (COM) height on stand-still postural sway analysis was studied. For this purpose, a measurement apparatus was set up that included an accelerometry device attached to a rod: three plumb lines, positioned at 50, 75 and 100 cm to an end of the rod, each supported a plumb bob. Using a vice mechanism, the rod was inclined from vertical (0 degree inclination) in steps of 5 degrees to 90 degrees. For each inclination, the corresponding inclination angle was manually measured by a protractor and the positions of the three plumb bobs on the ground surface were also manually measured using a tape measure. Algebraic operations were used to calculate the inclination angle and the associated displacements of the plumb bobs on the ground surface from the accelerometry data. For each inclination angle, the manual and accelerometry calculated ground displacement were close. The height of COM, where the measurement was taken, affected the projected displacement on the ground surface. The COM height had a nonlinear double-effect relationship with sway as it can affect both the angle and projected sway. Normalization of the COM height was used to reduce this effect for comparison purposes.
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Akhter, Romana, and Nigel B. Kaye. "Experimental investigation of a line plume in a filling box." Environmental Fluid Mechanics 20, no. 6 (2020): 1579–601. http://dx.doi.org/10.1007/s10652-020-09754-6.
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Abstract A series of experiments were conducted to quantify the dynamics of a filling box driven by a line plume that spans the full width of the enclosure. Three configurations were tested namely symmetric (centrally located plume), wall-bounded (plume attached to an end wall), and asymmetric. The front movement for the symmetric and wall-bounded configurations was well described by the standard filling box model. The front movement results indicate that the typical value of the entrainment coefficient $$ \left( \alpha \right) $$ α for an unconfined plume ($$ \alpha = 0.16 $$ α = 0.16 ) could be used to accurately predict the front movement for both the centrally located plume and the wall-attached plume. This is in contrast to other studies that suggest that wall-bounded plumes have a significantly lower entrainment coefficient. The standard filling box model broke down for the asymmetric configuration. As the plume was closer to one wall than the other, the plume outflows that spread out and reflected off the end walls returned to the plume at different times. This created a pressure imbalance across the plume that caused the plume to bend sharply toward the nearest wall. Analysis of the plume outflow as a constant flux gravity current showed that the outflow velocity scaled on the cube root of the plume buoyancy flux per unit width $$ f $$ f , a result confirmed by further experiments. This result was used to quantify the time at which the plume bends and the standard filling box model breaks down.
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Li, Shuo, and M. R. Flynn. "Cooling tower plume abatement and plume modeling: a review." Environmental Fluid Mechanics 21, no. 3 (2021): 521–59. http://dx.doi.org/10.1007/s10652-021-09790-w.
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AbstractVisible plumes above wet cooling towers are of great concern due to the associated aesthetic and environmental impacts. The parallel path wet/dry cooling tower is one of the most commonly used approaches for plume abatement, however, the associated capital cost is usually high due to the addition of the dry coils. Recently, passive technologies, which make use of free solar energy or the latent heat of the hot, moist air rising through the cooling tower fill, have been proposed to minimize or abate the visible plume and/or conserve water. In this review, we contrast established versus novel technologies and give a perspective on the relative merits and demerits of each. Of course, no assessment of the severity of a visible plume can be made without first understanding its atmospheric trajectory. To this end, numerous attempts, being either theoretical or numerical or experimental, have been proposed to predict plume behavior in atmospheres that are either uniform versus density-stratified or still versus windy (whether highly-turbulent or not). Problems of particular interests are plume rise/deflection, condensation and drift deposition, the latter consideration being a concern of public health due to the possible transport and spread of Legionella bacteria.
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Czinege, Anikó. "The setting of fenological- stadium of plum (Prunus domestica) varieties in 2012." Acta Agraria Debreceniensis, no. 51 (February 10, 2013): 93–96. http://dx.doi.org/10.34101/actaagrar/51/2069.
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We planted experimental trees, namely 6 plum varieties grafted on 6 plum rootstocks in the spring of 2010. Our aim was to observe differences in the fenological-stages of plum rootstock and variety combinations. ‘Cacanska lepotica’, ‘Jojo’,
 ‘Katinka’, ‘Topfive’, ‘Topper’, ‘Toptaste’ plum varieties were planted on ‘Mirobalan’ (Prunus ceresifera var. ceresifera cv. myrabolan); damson (Prunus institicia) – ‘St Julien A’, ‘St Julien GF655/2’; and ‘Wawit’; ‘Wangwnheim’; ‘Fereley’ rootstocks. We observed the bud burst, the flowering course: at the start of the flowering, during the main flowering, and at the end of flowerings and the ripening of the plum. Finally we observed the difference in leaves falling observed in the case of the different varieties and rootstock combinations.
 The bursting of buds started with ‘Cacanska lepotica’, in March 16 and finished with ‘Jojo’ / ‘Mirobalan’ combination, in March 22. The starting of flowering course was in March 29 with ‘Topper’ / ‘St Julien GF655/2’ combinations and the end of flowering course finished with ‘Toptaste’ varieties, in April 3–4. The start of ripening of the plum was with ‘Katinka’ / ‘St Julien A’ combinations, in July 17. and the end of ripening of the plum finished with ‘Topper’ variety. The start of leaves falling began with ‘Cacanska lepotica’, in Sept 5–8 depending on irrigation, and ‘Katinka’, ‘Jojo’ varieties finished, in November 28–29.
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Ezhova, Ekaterina, Claudia Cenedese, and Luca Brandt. "Dynamics of Three-Dimensional Turbulent Wall Plumes and Implications for Estimates of Submarine Glacier Melting." Journal of Physical Oceanography 48, no. 9 (2018): 1941–50. http://dx.doi.org/10.1175/jpo-d-17-0194.1.
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AbstractSubglacial discharges have been observed to generate buoyant plumes along the ice face of Greenland tidewater glaciers. These plumes have been traditionally modeled using classical plume theory, and their characteristic parameters (e.g., velocity) are employed in the widely used three-equation melt parameterization. However, the applicability of plume theory for three-dimensional turbulent wall plumes is questionable because of the complex near-wall plume dynamics. In this study, corrections to the classical plume theory are introduced to account for the presence of a wall. In particular, the drag and entrainment coefficients are quantified for a three-dimensional turbulent wall plume using data from direct numerical simulations. The drag coefficient is found to be an order of magnitude larger than that for a boundary layer flow over a flat plate at a similar Reynolds number. This result suggests a significant increase in the melting estimates by the current parameterization. However, the volume flux in a wall plume is found to be one-half that of a conical plume that has 2 times the buoyancy flux. This finding suggests that the total entrainment (per unit area) of ambient water is the same and that the plume scalar characteristics (i.e., temperature and salinity) can be predicted reasonably well using classical plume theory.
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Han, Yigui, Guochun Zhao, Peter A. Cawood, Min Sun, Qian Liu, and Jinlong Yao. "Plume-modified collision orogeny: The Tarim–western Tianshan example in Central Asia." Geology 47, no. 10 (2019): 1001–5. http://dx.doi.org/10.1130/g46855.1.
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Abstract Plume-modified orogeny involves the interaction between a mantle plume and subducting oceanic lithosphere at accretionary margins. We propose that a plume can also be involved in collisional orogeny and accounts for the late Paleozoic geological relations in Central Asia. Continental collision between the Tarim and Central Tianshan–Yili blocks at the end Carboniferous resulted in an orogeny lacking continental-type (ultra)high-pressure [(U)HP] rocks and significant syncollision surface erosion and uplift, features normally characteristic of continent-continent interactions. Their absence from the Tianshan region corresponded with the arrival of a mantle plume beneath the northern Tarim. Elemental and isotopic data reveal an increasing influence of the mantle plume on magmatic petrogenesis from ca. 300 to 280 Ma, immediately after collision at 310–300 Ma. The rising mantle plume interrupted the normal succession of collisional orogenic events, destroying the deeply subducted continental crust and hence preventing slab break-off–induced continental rebound. Plume-modified continental collision thus limited continental (U)HP rock exhumation and associated surface uplift.
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Delichatsios, M. A. "The Outflow of Buoyant Releases Including Fire Gases From a Long Corridor Closed at One End." Journal of Fluids Engineering 112, no. 1 (1990): 28–32. http://dx.doi.org/10.1115/1.2909364.
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A new simple model is presented for the outflow of buoyant releases, including fire gases, from a long corridor closed at one end. A physical description of the model and application to well-documented data justify and validate the present model. The analysis incorporates the interaction of gravity (buoyancy) forces, turbulence, and entrainment rates into the plume rising from the fire. The model provides equations for predicting the temperature rise and the velocity in the ceiling layer if one knows the heat release rate from the fire and the air entrainment into the fire plume before the plume is submerged in the ceiling layer. Limited data and analysis indicate that the present flow situation allows a maximum entrainment rate into the fire beyond which the rate of the flow entering the corridor at the open end cannot further increase, i.e., the flow is choked. Although the data analyzed in this paper could not include buoyant outflows produced by fires at the end of a long corridor, the present model can be extended to apply for such flows as it is suggested by a recent Japanese paper [6] and other similar flows [3]. Of course, more experiments using fires in corridors are desirable to validate the present model.
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von der Weiden-Reinmüller, S. L., F. Drewnick, Q. J. Zhang, F. Freutel, M. Beekmann, and S. Borrmann. "Megacity emission plume characteristics in summer and winter investigated by mobile aerosol and trace gas measurements: the Paris metropolitan area." Atmospheric Chemistry and Physics Discussions 14, no. 8 (2014): 11249–99. http://dx.doi.org/10.5194/acpd-14-11249-2014.
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Abstract. For the investigation of megacity emission plume characteristics mobile aerosol and trace gas measurements were carried out in the greater Paris region in July 2009 and January/February 2010 within the EU FP7 MEGAPOLI project. The deployed instruments measured physical and chemical properties of sub-micron aerosol particles, gas phase constituents of relevance for urban air pollution studies and meteorological parameters. The emission plume was identified based on fresh pollutant (e.g. particle-bound polycyclic aromatic hydrocarbons, black carbon, CO2 and NOx) concentration changes in combination with wind direction data. The classification into megacity influenced and background air masses allowed a characterization of the emission plume during summer and winter environmental conditions. On average, a clear increase of fresh pollutant concentrations in plume compared to background air masses was found for both seasons. For example, an average increase of 190% (+8.8 ng m−3) in summer and of 130% (+18.1 ng m−3) in winter was found for particle-bound polycyclic aromatic hydrocarbons in plume air masses. The aerosol particle size distribution in plume air masses was influenced by nucleation and growth due to coagulation and condensation in summer, while in winter only the second process seemed to be initiated by urban pollution. The observed distribution of fresh pollutants in the emission plume – its cross sectional Gaussian-like profile and the exponential decrease of pollutant concentrations with increasing distance to the megacity – are in agreement with model results. Differences between model and measurements were found for plume center location, plume width and axial plume extent. In general, dilution was identified as the dominant process determining the axial variations within the Paris emission plume. For in-depth analysis of transformation processes occurring in the advected plume, simultaneous measurements at a suburban measurement site and a stationary site outside the metropolitan area using the mobile laboratory have proven to be most useful. Organic aerosol oxidation was observed in summer, while in winter transformation processes seemed to occur at a slower rate.
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Preisler, Jan, and Edward S. Yeung. "Characterization of Matrix-Assisted Laser Desorption Based on Absorption and Acoustic Monitoring." Applied Spectroscopy 49, no. 12 (1995): 1826–33. http://dx.doi.org/10.1366/0003702953965920.
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Conventional methods for studying matrix-assisted desorption-ionization rely on mass spectroscopy. In this study, a 488-nm argon-ion laser beam is deflected by two acoustooptic deflectors to image plumes desorbed at atmospheric pressure via absorption. All species, including neutral molecules, are monitored. Interesting features, e.g., differences between the initial plume and subsequent plumes desorbed from the same spot, or the formation of two plumes from one laser shot, are observed. Total plume absorbance can be correlated with the acoustic signal generated by the desorption event. A model equation for the plume velocity as a function of time is proposed. Optical probing also enables accurate determination of plume velocities at reduced pressures. These results define the optimal conditions for desorbing analytes from matrices, as opposed to achieving a compromise between efficient desorption and efficient ionization as is practiced in mass spectrometry.
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Heue, K. P., C. A. M. Brenninkmeijer, A. K. Baker, et al. "SO<sub>2</sub> and BrO observation in the plume of the Eyjafjallajökull volcano 2010: CARIBIC and GOME-2 retrievals." Atmospheric Chemistry and Physics 11, no. 6 (2011): 2973–89. http://dx.doi.org/10.5194/acp-11-2973-2011.
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Abstract. The ash cloud of the Eyjafjallajökull (also referred to as: Eyjafjalla (e.g. Schumann et al., 2011), Eyjafjöll or Eyjafjoll (e.g. Ansmann et al., 2010)) volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) flying laboratory, which routinely measures at cruise altitude (≈11 km) performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2) and bromine monoxide (BrO) measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy) instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Average SO2 and BrO mixing ratios of ≈40 ppb and ≈5 ppt respectively are retrieved inside the plume. The BrO to SO2 ratio retrieved from the CARIBIC observation is ≈1.3×10−4. Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2) observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. As the CARIBIC O4 column densities changed rapidly during the plume observation, we conclude that the aerosol and the SO2 plume are collocated. For SO2 some additional information on the local distribution can be derived from a comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data.
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von der Weiden-Reinmüller, S. L., F. Drewnick, Q. J. Zhang, F. Freutel, M. Beekmann, and S. Borrmann. "Megacity emission plume characteristics in summer and winter investigated by mobile aerosol and trace gas measurements: the Paris metropolitan area." Atmospheric Chemistry and Physics 14, no. 23 (2014): 12931–50. http://dx.doi.org/10.5194/acp-14-12931-2014.
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Abstract. For the investigation of megacity emission plume characteristics mobile aerosol and trace gas measurements were carried out in the greater Paris region in July 2009 and January–February 2010 within the EU FP7 MEGAPOLI project (Megacities: Emissions, urban, regional and Global Atmospheric POLlution and climate effects, and Integrated tools for assessment and mitigation). The deployed instruments measured physical and chemical properties of sub-micron aerosol particles, gas phase constituents of relevance for urban air pollution studies and meteorological parameters. The emission plume was identified based on fresh pollutant (e.g., particle-bound polycyclic aromatic hydrocarbons, black carbon, CO2 and NOx) concentration changes in combination with wind direction data. The classification into megacity influenced and background air masses allowed a characterization of the emission plume during summer and winter environmental conditions. On average, a clear increase of fresh pollutant concentrations in plume compared to background air masses was found for both seasons. For example, an average increase of 190% (+ 8.8 ng m−3) in summer and of 130% (+ 18.1 ng m−3) in winter was found for particle-bound polycyclic aromatic hydrocarbons in plume air masses. The aerosol particle size distribution in plume air masses was influenced by nucleation and growth due to coagulation and condensation in summer, while in winter only the latter process (i.e., particle growth) seemed to be initiated by urban pollution. The observed distribution of fresh pollutants in the emission plume – its cross sectional Gaussian-like profile and the exponential decrease of pollutant concentrations with increasing distance to the megacity – are in agreement with model results. Differences between model and measurements were found for plume center location, plume width and axial plume extent. In general, dilution was identified as the dominant process determining the axial variations within the Paris emission plume. For in-depth analysis of transformation processes occurring in the advected plume, simultaneous measurements at a suburban measurement site and a stationary site outside the metropolitan area using the mobile laboratory have proven to be most useful. Organic aerosol oxidation was observed in summer, while in winter transformation processes seemed to occur at a slower rate.
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Besiktepe, Sükrü T., Emin Özsoy, and M. Abdul Latif. "Sewage outfall plume in the two-layer channel: an example of Istanbul outfall." Water Science and Technology 32, no. 2 (1995): 69–75. http://dx.doi.org/10.2166/wst.1995.0076.
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Municipal wastewater from the city of Istanbul is discharged into the Bosphorus Strait through an outfall built on the southern end of the Strait. The behaviour of the wastewater plume in the Bosphorus environment is quite complicated as a result of the two-layer stratification, the rapid currents flowing in opposite directions in each layer, their transverse variations, and the turbulence and entrainment processes in the ambient waters. The wastewater is injected from 22 diffuser ports on each of the two pipelines located in a depth range of 40-60 m. The numerous plumes from the multiple ports combine to yield a line source of plume-like behaviour in the far-field. The plume typically rises due to its buoyancy in the lower layer, and becomes arrested at the interface between the upper and lower layers of the Bosphorus, but the swift undercurrents bend the plume to align it with the interface along the Bosphorus.
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Ramos, P., S. R. Cunha, M. V. Neves, F. L. Pereira, and I. Quintaneiro. "Sewage outfall plume dispersion observations with an Autonomous Underwater Vehicle." Water Science and Technology 52, no. 12 (2005): 283–90. http://dx.doi.org/10.2166/wst.2005.0485.
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This work represents one of the first successful applications of Autonomous Underwater Vehicles (AUVs) for interdisciplinary coastal research. A monitoring mission to study the shape and estimate the initial dilution of the S. Jacinto sewage outfall plume using an AUV was performed on July 2002. An efficient sampling strategy enabling greater improvements in spatial and temporal range of detection demonstrated that the sewage effluent plume can be clearly traced using naturally occurring tracers in the wastewater. The outfall plume was found at the surface highly influenced by the weak stratification and low currents. Dilution varying with distance downstream was estimated from the plume rise over the outfall diffuser until a nearly constant value of 130:1, 60m from the diffuser, indicating the near field end. Our results demonstrate that AUVs can provide high-quality measurements of physical properties of effluent plumes in a very effective manner and valuable considerations about the initial mixing processes under real oceanic conditions can be further investigated.
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Yang, Di, Bicheng Chen, Scott A. Socolofsky, Marcelo Chamecki, and Charles Meneveau. "Large-eddy simulation and parameterization of buoyant plume dynamics in stratified flow." Journal of Fluid Mechanics 794 (April 7, 2016): 798–833. http://dx.doi.org/10.1017/jfm.2016.191.
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Characteristics of laboratory-scale bubble-driven buoyant plumes in a stably stratified quiescent fluid are studied using large-eddy simulation (LES). As a bubble plume entrains stratified ambient water, its net buoyancy decreases due to the increasing density difference between the entrained and ambient fluids. A large fraction of the entrained fluid eventually detrains and falls along an annular outer plume from a height of maximum rise (peel height) to a neutral buoyancy level (trap height), during which less buoyant scalars (e.g. small droplets) are trapped and dispersed horizontally, forming quasi-horizontal intrusion layers. The inner/outer double-plume structure and the peel/intrusion process are found to be more distinct for cases with small bubble rise velocity, while weak and unstable when the slip velocity is large. LES results are averaged to generate distributions of mean velocity and turbulent fluxes. These distributions provide data for assessing the performance of previously developed closures used in one-dimensional integral plume models. In particular, the various LES cases considered in this study yield consistent behaviour for the entrainment coefficients for various plume cases. Furthermore, a new continuous peeling model is derived based on the insights obtained from LES results. Comparing to previous peeling models, the new model behaves in a more self-consistent manner, and it is expected to provide more reliable performance when applied in integral plume models.
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Zheng, Yi, Hai Lan, Magesh Thiruvengadam, Jerry C. Tien, and Ying Li. "Effect of single dead end entry inclination on DPM plume dispersion." International Journal of Mining Science and Technology 27, no. 3 (2017): 401–6. http://dx.doi.org/10.1016/j.ijmst.2017.03.003.
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CAMPBELL, A. N., and S. S. S. CARDOSO. "Turbulent plumes with internal generation of buoyancy by chemical reaction." Journal of Fluid Mechanics 655 (July 5, 2010): 122–51. http://dx.doi.org/10.1017/s0022112010000728.
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Turbulent plumes, which are seen in a wide number of industrial and natural flows, have been extensively studied; however, very little attention has been paid to plumes which have an internal mechanism for changing buoyancy. Such plumes arise in e.g. industrial chimneys, where species can react and change the density of the plume material. These plumes with chemical reaction are the focus of this study. An integral model describing the behaviour of a plume undergoing a second-order chemical reaction between a component in the plume (A) and a component in the surrounding fluid (B), which alters the buoyancy flux, is considered. The behaviour of a reactive plume is shown to depend on four dimensionless groups: the volume and momentum fluxes at the source, the parameter ϵ which indicates the additional buoyancy flux generated by the reaction and γ which is a dimensionless rate of depletion of species B. Additionally, approximate analytical solutions are sought for a reactive plume rising from a point source of buoyancy when species B is in great excess. These analytical results show excellent agreement with numerical simulations. It is also shown that the behaviour of a reactive plume in the far field is equivalent to an inert plume issuing from a virtual source downstream of the real source, and the dependence of the location of the virtual source on ϵ and γ is discussed. The effects of varying the volume flux at the source and the Morton source parameter Γ0 are further investigated by solving the full governing equations numerically. These solutions indicate that ϵ is important in determining the buoyancy generated by the reaction, and the length scale over which this reaction occurs depends on γ when γ > 1. It is also shown that when the dimensionless buoyancy ϵ < − 1, the reaction can cause the plume to collapse.
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Matulka, A., P. López, J. M. Redondo, and A. Tarquis. "On the entrainment coefficient in a forced plume: quantitative effects of source parameters." Nonlinear Processes in Geophysics 21, no. 1 (2014): 269–78. http://dx.doi.org/10.5194/npg-21-269-2014.
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Abstract. The behavior of a forced plume is mainly controlled by the source buoyancy and momentum fluxes and the efficiency of turbulent mixing between the plume and the ambient fluid (stratified or not). The interaction between the plume and the ambient fluid controls the plume dynamics and is usually represented by the entrainment coefficient αE. Commonly used one-dimensional models incorporating a constant entrainment coefficient are fundamental and very useful for predictions in geophysical flows and industrial situations. Nevertheless, if the basic geometry of the flow changes, or the type of source or the environmental fluid conditions (e.g., level of turbulence, shear, ambient stratification, presence of internal waves), new models allowing for variable entrainment are necessary. The presented paper is an experimental study based on a set of turbulent plume experiments in a calm unstratified ambient fluid under different source conditions (represented by different buoyancy and momentum fluxes). The main result is that the entrainment coefficient is not a constant and clearly varies in time within the same plume independently of the buoyancy and the source position. This paper also analyzes the influence of the source conditions on the mentioned time evolution. The measured entrainment coefficient αE has considerable variability. It ranges between 0.26 and 0.9 for variable Atwood number experiments and between 0.16 and 0.55 for variable source position experiments. As is observed, values are greater than the traditional standard value of Morton et al. (1956) for plumes and jets, which is about 0.13.
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Chouza, Fernando, Thierry Leblanc, John Barnes, Mark Brewer, Patrick Wang, and Darryl Koon. "Long-term (1999–2019) variability of stratospheric aerosol over Mauna Loa, Hawaii, as seen by two co-located lidars and satellite measurements." Atmospheric Chemistry and Physics 20, no. 11 (2020): 6821–39. http://dx.doi.org/10.5194/acp-20-6821-2020.
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Abstract. As part of the Network for the Detection of Atmospheric Composition Change (NDACC), ground-based measurements obtained from the Jet Propulsion Laboratory (JPL) stratospheric ozone lidar and the NOAA stratospheric aerosol lidar at Mauna Loa, Hawaii, over the past 2 decades were used to investigate the impact of volcanic eruptions and pyrocumulonimbus (PyroCb) smoke plumes on the stratospheric aerosol load above Hawaii since 1999. Measurements at 355 and 532 nm conducted by these two lidars revealed a color ratio of 0.5 for background aerosols and small volcanic plumes and 0.8 for a PyroCb plume recorded on September 2017. Measurements of the Nabro plume by the JPL lidar in 2011–2012 showed a lidar ratio of (64±12.7) sr at 355 nm around the center of the plume. The new Global Space-based Stratospheric Aerosol Climatology (GloSSAC), Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) Level 3 and Stratospheric Aerosol and Gas Experiment III on the International Space Station (SAGE III-ISS) stratospheric aerosol datasets were compared to the ground-based lidar datasets. The intercomparison revealed a generally good agreement, with vertical profiles of extinction coefficient within 50 % discrepancy between 17 and 23 km above sea level (a.s.l.) and 25 % above 23 km a.s.l. The stratospheric aerosol depth derived from all of these datasets shows good agreement, with the largest discrepancy (20 %) being observed between the new CALIOP Level 3 and the other datasets. All datasets consistently reveal a relatively quiescent period between 1999 and 2006, followed by an active period of multiple eruptions (e.g., Nabro) until early 2012. Another quiescent period, with slightly higher aerosol background, lasted until mid-2017, when a combination of extensive wildfires and multiple volcanic eruptions caused a significant increase in stratospheric aerosol loading. This loading maximized at the very end of the time period considered (fall 2019) as a result of the Raikoke eruption, the plume of which ascended to 26 km altitude in less than 3 months.
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Petetin, H., M. Beekmann, A. Colomb, et al. "Evaluating BC and NO<sub>x</sub> emission inventories for the Paris region from MEGAPOLI aircraft measurements." Atmospheric Chemistry and Physics Discussions 14, no. 21 (2014): 29237–304. http://dx.doi.org/10.5194/acpd-14-29237-2014.
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Abstract. High uncertainties affect black carbon (BC) emissions and, despite its important impact on air pollution and climate, very few BC emissions evaluations are found in the literature. This paper presents a novel approach, based on airborne measurements across the Paris plume, developed in order to evaluate BC and NOx emissions at the scale of a whole agglomeration. The methodology consists in integrating, for each transect, across the plume observed and simulated concentrations above background. This allows minimizing several error sources in the model (e.g. representativeness, chemistry, plume lateral dispersion). The procedure is applied with the CHIMERE chemistry-transport model to three inventories – the EMEP inventory, and the so-called TNO and TNO-MP inventories – over the month of July 2009. Various systematic uncertainty sources both in the model (e.g. boundary layer height, vertical mixing, deposition) and in observations (e.g. BC nature) are discussed and quantified, notably though sensitivity tests. A statistically significant (but moderate) overestimation is obtained on the TNO BC emissions and on EMEP and TNO-MP NOx emissions, as well as on the BC/NOx emission ratio in TNO-MP. The benefit of the airborne approach is discussed through a comparison with the BC/NOx ratio at a ground site in Paris, which additionally suggests potential error compensations in the BC emissions spatial distribution over the agglomeration.
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Anderson, Kerry, Al Pankratz, Curtis Mooney, and Kelly Fleetham. "The Alberta smoke plume observation study." Earth System Science Data 10, no. 1 (2018): 325–37. http://dx.doi.org/10.5194/essd-10-325-2018.
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Abstract. A field project was conducted to observe and measure smoke plumes from wildland fires in Alberta. This study used handheld inclinometer measurements and photos taken at lookout towers in the province. Observations of 222 plumes were collected from 21 lookout towers over a 6-year period from 2010 to 2015. Observers reported the equilibrium and maximum plume heights based on the plumes' final levelling heights and the maximum lofting heights, respectively. Observations were tabulated at the end of each year and matched to reported fires. Fire sizes at assessment times and forest fuel types were reported by the province. Fire weather conditions were obtained from the Canadian Wildland Fire Information System (CWFIS). Assessed fire sizes were adjusted to the appropriate size at plume observation time using elliptical fire-growth projections. Though a logical method to collect plume observations in principle, many unanticipated issues were uncovered as the project developed. Instrument limitations and environmental conditions presented challenges to the investigators, whereas human error and the subjectivity of observations affected data quality. Despite these problems, the data set showed that responses to fire behaviour conditions were consistent with the physical processes leading to plume rise. The Alberta smoke plume observation study data can be found on the Canadian Wildland Fire Information System datamart (Natural Resources Canada, 2018) at http://cwfis.cfs.nrcan.gc.ca/datamart.
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Tseng, Y. F., J. Lin, M. Dai, and S. J. Kao. "Joint effect of freshwater plume and coastal upwelling on phytoplankton growth off the Changjiang River." Biogeosciences 11, no. 2 (2014): 409–23. http://dx.doi.org/10.5194/bg-11-409-2014.
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Abstract. The Changjiang (Yangtze) River discharges vast amount of unbalanced nutrients (dissolved inorganic nitrogen and phosphorus with N / P ratio > 80 in general) into the East China Sea in summer. To study nutrient dynamics and P-stress potential for phytoplankton, a cruise was conducted in the Changjiang plume during summer 2011. With 3-D observations of nutrients, chlorophyll a (Chl a), and bulk alkaline phosphatase activity (APA), we concluded that the Changjiang Diluted Water and coastal upwelling significantly influenced the horizontal and vertical heterogeneities of phytoplankton P deficiency in the Changjiang plume. Allochthonous APA was detected at nutrient-enriched freshwater end. Excessive N (~ 10 to 112 μM) was observed throughout the entire plume surface. In the plume fringe featuring stratification and excess N, diapycnal phosphate supply was blocked and phytoplankton APA was stimulated for growth. We observed an upwelling just attaching to the turbidity front at seaward side where Chl a peaked yet much less APA was detected. An external phosphate supply from subsurface, which promoted phytoplankton growth but inhibited APA, was suggested to be sourced from the Nearshore Kuroshio Branch Current. In the so hydrographically complicated Changjiang plume, phosphate supply instead of its concentration may be more important in determining the expression of APA. Meanwhile, allochthonous APA may also alter the usefulness of APA as a P-stress indicator.
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Comina, C., M. Lasagna, D. A. De Luca, and L. Sambuelli. "Discharge measurement with salt dilution method in irrigation canals: direct sampling and geophysical controls." Hydrology and Earth System Sciences Discussions 10, no. 8 (2013): 10035–60. http://dx.doi.org/10.5194/hessd-10-10035-2013.
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Abstract. An important starting point for designing management improvements, particularly in irrigation areas, is to record the baseline state of the water resources, including the amount of discharge from canals. In this respect discharge measurements by means of the salt dilution method is a traditional and well-documented technique. However, this methodology can be strongly influenced by the natural streaming characteristics of the canal (e.g. laminar vs. turbulent flow) and accurate precautions must be considered in the choice of both the measuring section and the length of the measuring reach of the canal which can affect the plume shape. The knowledge of plume distribution in the measuring cross-section is of primary importance for a correct location of sampling points aimed in obtaining a reliable measurement. To obtain this, geophysical imaging of an NaCl plume from a slug-injection salt dilution test has been performed within this paper by means of cross-flow fast electric resistivity tomography (FERT) in a real case history. Direct sampling of the same plume has been also performed with a multisampling optimization technique to obtain an average value over the measuring section by means of contemporarily sampling water in nine points. Results show that a correct visualization of the passage of the salt plume is possible by means of geophysical controls and that this can potentially help in the correct location of sampling points.
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Tseng, Y. F., J. Lin, M. Dai, and S. J. Kao. "Joint effect of freshwater plume and coastal upwelling on phytoplankton growth off the Changjiang River." Biogeosciences Discussions 10, no. 6 (2013): 10363–97. http://dx.doi.org/10.5194/bgd-10-10363-2013.
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Abstract. Changjiang River discharges vast amount of unbalanced nutrients (dissolved inorganic nitrogen (N) and phosphorus (P) with N / P > 80 in general) into the East China Sea during summertime. To explore nutrient dynamics and P stress potential for phytoplankton, a cruise was conducted in the Changjiang plume during summer 2011. With 3-D observations of nutrients, chlorophyll a (Chl a), and bulk alkaline phosphatase activity (APA), we concluded that the Changjiang Diluted Water (CDW) and coastal upwelling significantly influenced the horizontal and vertical heterogeneities of phytoplankton P-deficiency in the plume. Allochthonous APA was detected at nutrient-enriched freshwater end. Excessive N (~10 to 112 µM) was obserevd throughout the entire plume surface. In the plume fringe where featured by stratification and excess N, diapycnal phosphate supply was blocked to stimulate APA for phytoplankton growth. We observed upwelling outcrops just attaching the turbidity front at seaward side, where Chl a peaked yet much less APA was detected. An external phosphate supply from subsurface, which stimulated phytoplankton growth but inhibited APA, was suggested and the supply was likely sourced from the Nearshore Kuroshio Branch Current. In such hydrographically complicated Changjiang plume, phosphate supply instead of its concentration was more important determining the expression of APA. Meanwhile, allochthounous APA may also alter the usefulness of APA as a P-stress indicator.
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Liu, Mengying, Zhu Liu, Shipeng Li, Wenhao Yu, Jian Cao, and Ningfei Wang. "Study on Size Distribution and Flow Characteristics of Condensed Products in Solid Rocket Motor." International Journal of Aerospace Engineering 2021 (August 4, 2021): 1–10. http://dx.doi.org/10.1155/2021/5481436.
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The size distribution of condensed products during the combustion of aluminized propellants and flow characteristics of the gas-solid two-phase flow in solid rocket motor were studied in this paper. Firstly, based on the laser scattering technology, an online detection system for condensed products in plume was established, and the size detection of condensed products in the plume of solid rocket motor is carried out. Secondly, a numerical model of two-phase flow in solid rocket motor is established by combining the real size distribution of products in the plume with discrete phase model through the Rosin-Rammler distribution function. Besides, numerical simulation research is carried out under the same experimental conditions, focusing on the influence of condensed products with real size on the characteristics of solid rocket motor. The results show that the innovation measurement system can be used to obtain the size distribution characteristic of condensed products in the plume. At the particle size of stable stage, the mean size, D v 50 , is 104 μm, which is the smallest among all stages. It is also suggested that condensed products at the end stage have the most impact on the flow behavior in solid rocket motor, in that the shock structure, Mach number, and temperature distribution in the near field of plume are significantly changed.
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Damico, James R., Robert W. Ritzi, Naum I. Gershenzon, and Roland T. Okwen. "Challenging Geostatistical Methods To Represent Heterogeneity in CO2 Reservoirs Under Residual Trapping." Environmental and Engineering Geoscience 24, no. 4 (2018): 357–73. http://dx.doi.org/10.2113/eeg-2116.
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Abstract Geostatistical methods based on two-point spatial-bivariate statistics have been used to model heterogeneity within computational studies of the dispersion of contaminants in groundwater reservoirs and the trapping of CO2 in geosequestration reservoirs. The ability of these methods to represent fluvial architecture, commonly occurring in such reservoirs, has been questioned. We challenged a widely used two-point spatial-bivariate statistical method to represent fluvial heterogeneity in the context of representing how reservoir heterogeneity affects residual trapping of CO2 injected for geosequestration. A more rigorous model for fluvial architecture was used as the benchmark in these studies. Both the geostatistically generated model and the benchmark model were interrogated, and metrics for the connectivity of high-permeability preferential flow pathways were quantified. Computational simulations of CO2 injection were performed, and metrics for CO2 dynamics and trapping were quantified. All metrics were similar between the two models. The percentage of high-permeability cells in spanning connected clusters (percolating clusters) was similar because percolation is strongly dependent upon proportions, and the same proportion of higher permeability cross-strata was specified in generating both models. The CO2 plume dynamics and residual trapping metrics were similar because they are largely controlled by the occurrence of percolating clusters. The benchmark model represented more features of the fluvial architecture and, depending on context, representing those features may be quite important, but the simpler geostatistical model was able to adequately represent fluvial reservoir architecture within the context and within the scope of the parameters represented here.
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PANDA, J. "Experimental investigation of turbulent density fluctuations and noise generation from heated jets." Journal of Fluid Mechanics 591 (October 30, 2007): 73–96. http://dx.doi.org/10.1017/s0022112007007173.
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Low-frequency noise sources in heated single-stream jets were identified by cross-correlating turbulent density fluctuations ρ′ with the far-field sound pressure fluctuations p′. The turbulent density fluctuations were measured by a molecular Rayleigh-scattering technique. For a fixed jet velocity Uj, the normalized correlation coefficient 〈ρ′; p′〉/(ρ′rmsp′rms is found to increase progressively with an increase in the plume temperature (subscript rms stands for root-mean-square). The result indicates an improvement of the noise radiation efficiency with heating. Directly measured noise spectra from fixed velocity jets with increasing temperature ratio show confusing trends. However, if such spectra are normalized by theplume density, then a consistent trend of increasing noise level with increased plume temperature emerges. The increased noise is the most prominent at the low-frequency end, consistent with the correlation data. The effect of increasing jet velocity keeping the plume temperature constant was also studied. The correlation coefficients were found to improve significantly with velocity; a result consistent with prior observation from unheated jets. Additional findings on the time-averaged density variations and the changes in the air density fluctuations with increasing plume temperature are also discussed.
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WITHAM, FRED, and JEREMY C. PHILLIPS. "The dynamics and mixing of turbulent plumes in a turbulently convecting environment." Journal of Fluid Mechanics 602 (April 25, 2008): 39–61. http://dx.doi.org/10.1017/s0022112008000682.
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The turbulent motion of buoyant plumes released into turbulently convecting environments is studied. By assuming that the turbulent environment removes fluid from the plume at a rate proportional to a characteristic environmental velocity scale, we derive a model describing the fluid behaviour. For the example of pure buoyancy plumes, entrainment dominates near the source and the plume radius increases with distance, while further from the source removal, or extrainment, of plume material dominates, and the plume radius decreases to zero. Theoretical predictions are consistent with laboratory experiments, a major feature of which is the natural variability of the convection. We extend the study to include the evolution of a finite confined environment, the end-member regimes of which are a well-mixed environment at all times (high convective velocities), and a ‘filling-box’ model similar to that of Baines & Turner (1969) (low convective velocities). These regimes, and the motion of the interface in a ‘filling-box’ experiment, match experimental observations. We find that the convecting filling box is not stable indefinitely, but that the density stratification will eventually be overcome by thermal convection. The model presented here has important applications in volcanology, ventilation studies and environmental science.
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Roberts, T. J., R. S. Martin, and L. Jourdain. "Reactive bromine chemistry in Mt. Etna's volcanic plume: the influence of total Br, high temperature processing, aerosol loading and plume-air mixing." Atmospheric Chemistry and Physics Discussions 14, no. 5 (2014): 5445–94. http://dx.doi.org/10.5194/acpd-14-5445-2014.
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Abstract. Volcanic emissions present a source of reactive halogens to the troposphere, through rapid plume chemistry that converts the emitted HBr to more reactive forms such as BrO. The nature of this process is poorly quantified, yet is of interest to understand volcanic impacts on the troposphere, and infer volcanic activity from volcanic gas measurements (i.e. BrO / SO2 ratios). Recent observations from Etna report an initial increase and subsequent plateau or decline in BrO / SO2 ratios with distance downwind. We present daytime PlumeChem model simulations that reproduce and explain the reported trend in BrO / SO2 at Etna including the initial rise and subsequent plateau. Through suites of model simulations we also investigate the influences of volcanic aerosol loading, bromine emission, and plume-air mixing rate on the downwind plume chemistry. Emitted volcanic HBr is converted into reactive bromine by autocatalytic bromine chemistry cycles whose onset is accelerated by the model high-temperature initialisation. These rapid chemistry cycles also impact the reactive bromine speciation through inter-conversion of Br, Br2, BrO, BrONO2, BrCl, HOBr. Formation of BrNO2 is also discussed. We predict a new evolution of Br-speciation in the plume, with BrO, Br2, Br and HBr as the main plume species in the near downwind plume whilst BrO, and HOBr are present in significant quantities further downwind (where BrONO2 and BrCl also make up a minor fraction). The initial rise in BrO / SO2 occurs as ozone is entrained into the plume whose reaction with Br promotes net formation of BrO. Aerosol has a modest impact on BrO / SO2 near-downwind (< 6 km) at the relatively high loadings considered. The subsequent decline in BrO / SO2 occurs as entrainment of oxidants HO2 and NO2 promotes net formation of HOBr and BrONO2, whilst the plume dispersion dilutes volcanic aerosol so slows the heterogeneous loss rates of these species. A higher volcanic aerosol loading enhances BrO / SO2 in the (> 6 km) downwind plume. Simulations assuming low/medium and high Etna bromine emissions scenarios show the bromine emission has a greater influence on BrO / SO2 further downwind and a modest impact near downwind, and show either complete or partial conversion of HBr into reactive bromine, respectively, yielding BrO contents that reach up to ∼50% or ∼20% of total bromine (over a timescale of a few 10's of minutes). Plume-air mixing (which in our model with fixed plume dimensions is inversely related to the volcanic emission flux) non-linearly impacts the downwind BrO / SO2. A slower rate of plume-air mixing (or greater volcanic emission flux) leads to lower BrO / SO2 ratios near downwind, but also delays the subsequent decline in BrO / SO2, thus yields higher BrO / SO2 ratios further downwind. We highlight the important role of plume chemistry models for the interpretation of observed changes in BrO / SO2 during/prior to volcanic eruptions, as well as for quantifying volcanic plume impacts on atmospheric chemistry. Simulated plume impacts include ozone, HOx and NOx depletion, the latter converted into HNO3. Partial recovery of ozone concentrations occurs with distance downwind (as BrO concentrations decline), although cumulative ozone loss is ongoing over the 3 h simulations. We suggest plume BrNO2 may be less prevalent than previous model predictions. We highlight additional reactions for BrNO2 (and alternative pathways via BrONO) which likely reduce in-plume BrNO2 prevalence. We also highlight uncertainty in volcanic NOx emissions that might be lower than previously assumed (i.e., equilibrium NOx), due to the slow rate of N2 oxidation. The atmospheric : magmatic gas ratio, VA : VM, in equilibrium model representations of the near vent plume is presently poorly defined. Using a revised equilibrium model methodology, lower VA : VM become suitable (e.g. VA : VM = 98 : 2, 95 : 5), which also yield a lower estimate for volcanic NOx, although uncertainties to such equilibrium model representations of near-vent plume chemistry and especially NOx formation are emphasized.
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Broadley, Michael W., Peter H. Barry, Chris J. Ballentine, Lawrence A. Taylor, and Ray Burgess. "End-Permian extinction amplified by plume-induced release of recycled lithospheric volatiles." Nature Geoscience 11, no. 9 (2018): 682–87. http://dx.doi.org/10.1038/s41561-018-0215-4.
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Dēķena, Dzintra, Ina Alsiņa, Valda Laugale, and Kersti Kahu. "Influence of Rootstocks on Winter-Hardiness of Plum Generative Buds During the Wintering Period in Two Growing Regions." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 73, no. 3 (2019): 252–56. http://dx.doi.org/10.2478/prolas-2019-0040.
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Abstract The selection of appropriate rootstock is the main precondition for obtaining a high yielding and sustainable plum orchard. In the Northern climate, plum overwintering is especially important, where winter hardiness of flower buds is one of indicators. This investigation was carried out during three wintering periods (2010–2013) at the Institute of Horticulture in Pūre (Latvia) and the Polli Horticultural Research Centre (Estonia), in orchards planted in 2001. The aim of the investigation was to evaluate the influence of different rootstocks on the viability of flower buds during winter for two plum cultivars in two growing regions. European plum ‘Victoria’ and hybrid plum ‘Kubanskaya Kometa’ grafted on eight clonal and eight seedling rootstocks were used in the investigation. Bud samples were taken two times during winter: end of January and end of March. The viability of flower buds and flowering intensity were determined in the laboratory. The viability was determined as dehydrogenase activity using triphenyl tetrazole chloride (0.5%), where in living cells the colourless substance due to enzymatic activity turns into a brightly coloured product — formasan. The optical density of colour was determined with a spectrophotometer at 485 nm. Both cultivars ‘Kubanskaya Kometa’ and ‘Victoria’ had higher flower bud viability in Polli compare to Pūre. In both growing regions, the highest activity of dehydrogenases for cultivar ‘Kubanskaya Kometa’ was on rootstocks ‘Myrobalan’, ‘St. Julien INRA 2’, ‘Wangenheims Zwetsche’ and for cultivar ‘Victoria’ — on rootstocks ‘Ackermann’, ‘Brompton’ seedlings, and ‘St. Julien d’ Orleans’. The dehydrogenase activity of in flower buds had a tendency to decrease during winter.
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Petetin, H., M. Beekmann, A. Colomb, et al. "Evaluating BC and NO<sub><i>x</i></sub> emission inventories for the Paris region from MEGAPOLI aircraft measurements." Atmospheric Chemistry and Physics 15, no. 17 (2015): 9799–818. http://dx.doi.org/10.5194/acp-15-9799-2015.
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Abstract. High uncertainties affect black carbon (BC) emissions, and, despite its important impact on air pollution and climate, very few BC emissions evaluations are found in the literature. This paper presents a novel approach, based on airborne measurements across the Paris, France, plume, developed in order to evaluate BC and NOx emissions at the scale of a whole agglomeration. The methodology consists in integrating, for each transect, across the plume observed and simulated concentrations above background. This allows for several error sources (e.g., representativeness, chemistry, plume lateral dispersion) to be minimized in the model used. The procedure is applied with the CHIMERE chemistry-transport model to three inventories – the EMEP inventory and the so-called TNO and TNO-MP inventories – over the month of July 2009. Various systematic uncertainty sources both in the model (e.g., boundary layer height, vertical mixing, deposition) and in observations (e.g., BC nature) are discussed and quantified, notably through sensitivity tests. Large uncertainty values are determined in our results, which limits the usefulness of the method to rather strongly erroneous emission inventories. A statistically significant (but moderate) overestimation is obtained for the TNO BC emissions and the EMEP and TNO-MP NOx emissions, as well as for the BC / NOx emission ratio in TNO-MP. The benefit of the airborne approach is discussed through a comparison with the BC / NOx ratio at a ground site in Paris, which additionally suggests a spatially heterogeneous error in BC emissions over the agglomeration.
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Nicholson, Suzanne W., Klaus J. Schulz, Steven B. Shirey, and John C. Green. "Rift-wide correlation of 1.1 Ga Midcontinent rift system basalts: implications for multiple mantle sources during rift development." Canadian Journal of Earth Sciences 34, no. 4 (1997): 504–20. http://dx.doi.org/10.1139/e17-041.
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Magmatism that accompanied the 1.1 Ga Midcontinent rift system (MRS) is attributed to the upwelling and decompression melting of a mantle plume beneath North America. Five distinctive flood-basalt compositions are recognized in the rift-related basalt succession along the south shore of western Lake Superior, based on stratigraphically correlated major element, trace element, and Nd isotopic analyses. These distinctive compositions can be correlated with equivalent basalt types in comparable stratigraphic positions in other MRS localities around western Lake Superior. Four of these compositions are also recognized at Mamainse Point more than 200 km away in eastern Lake Superior. These regionally correlative basalt compositions provide the basis for determining the sequential contribution of various mantle sources to flood-basalt magmatism during rift development, extending a model originally developed for eastern Lake Superior. In this refined model, the earliest basalts were derived from small degrees of partial melting at great depth of an enriched, ocean-island-type plume mantle source (εNd(1100) value of about 0), followed by magmas representing melts from this plume source and interaction with another mantle source, most likely continental lithospheric mantle (εNd(1100) < 0). The relative contribution of this second mantle source diminished with time as larger degree partial melts of the plume became the dominant source for the voluminous younger basalts (εNd(1100) value of about 0). Towards the end of magmatism, mixtures of melts from the plume and a depleted asthenospheric mantle source became dominant (εNd(1100) = 0 to +3).
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Ma, Yongxing, M. R. Flynn, and Bruce R. Sutherland. "Convection from a line-source into a two-layer stratified ambient fluid." Journal of Fluid Mechanics 818 (March 28, 2017): 46–67. http://dx.doi.org/10.1017/jfm.2017.143.
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We experimentally investigate the behaviour of a line-source plume falling through a finite two-layer stratified ambient where the depth of the upper ambient layer increases in time. Laboratory observations suggest one of two possible flow regimes depending on the value of $\unicode[STIX]{x1D706}$, which represents the relative loss of buoyancy experienced by the plume upon crossing the ambient interface. When $\unicode[STIX]{x1D706}>1$, a classical filling-box-type flow is realized and plume fluid always reaches the bottom boundary. By contrast, when $\unicode[STIX]{x1D706}<1$, we observe a transition by which an increasing fraction of plume fluid discharges along the interface. The approximate start time, $t_{v}$, and end time, $t_{t}$, of the transition process are well determined by $\unicode[STIX]{x1D706}$. After transition, the ambient density evolves to form a three-layer fluid with an intermediate layer that grows in time. Measured densities of the intermediate layer in experiments with $\unicode[STIX]{x1D706}<1$ are well predicted using plume theory. We further characterize the horizontal speed of the intrusion that forms along the ambient interface, the mass of solute present in the intermediate layer at time $t_{t}$ and the rate of descent of the intrusion level for $t>t_{t}$. The significance of our findings is discussed in the context of the ventilation of natural and hybrid ventilated buildings and of effluent discharge through marine outfall diffusers.
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Skotniczny, Magdalena, Paweł Satora, Katarzyna Pańczyszyn, and Monika Cioch-Skoneczny. "Growth Dynamics and Diversity of Yeasts during Spontaneous Plum Mash Fermentation of Different Varieties." Foods 9, no. 8 (2020): 1054. http://dx.doi.org/10.3390/foods9081054.
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The influence of fruit varieties on yeast ecology during spontaneous plum mash fermentation was investigated. Yeast colonies were isolated from mashes obtained from four plum varieties throughout fermentation in laboratory conditions during two consecutive years. The yeast strains were differentiated by random amplification of polymorphic DNA (RAPD-PCR) and identified by the 26S rDNA D1/D2 sequence analysis. Hanseniaspora uvarum, Metschnikowia spp. and Pichia kudriavzevii were the dominant yeasts during the early stages of plum mash fermentation, while the middle and end phases were dominated by Saccharomyces cerevisiae. The strains of Candida sake, Nakazawaea ernobii, Pichia kluyveri, Rhodotorula mucilaginosa and Wickerhamomyces anomalus were also detected in fermenting plum mashes. Metschnikowia sp. M1, H. uvarum H1 and H2 strains were detected in all samples, irrespective of the tested variety and year. Investigation of the impact of individual yeast strains on the production of volatile compounds showed the potential possibility of using them as starter cultures.
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MAXWORTHY, T. "The flickering candle: transition to a global oscillation in a thermal plume." Journal of Fluid Mechanics 390 (July 10, 1999): 297–323. http://dx.doi.org/10.1017/s002211209900508x.
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A number of experiments have been performed on the properties of propane diffusion flames at relatively low fuel flow rates and using a variety of burner types. Optical methods were used to observe the flame and plume above it. We have studied the transition from a steady flame, with a plume exhibiting a helical instability at low flow rates, to an axisymmetric instability of the whole flame/plume, that grows from the base of the flame and oscillates at a well-defined and robust frequency, at higher flow rates. These results and the observation of the effects of various external modifications, e.g. the generation of an annular counter flow, a pressure perturbation, etc. are consistent with the view that the transition to the axisymmetric state, at which the flame flickers, is one to a globally excited oscillation forced by a region of absolutely unstable flow at or near the base of the burners used in this study.
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Uchiyama, Tomomi, and Shunsuke Sasaki. "Experimental Investigation of the Interaction between Rising Bubbles and Swirling Water Flow." International Journal of Chemical Engineering 2014 (2014): 1–10. http://dx.doi.org/10.1155/2014/358241.
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This study experimentally investigates the interaction between rising bubbles and swirling water flow imposed around the central (vertical) axis of a bubble plume in a cylindrical water tank. Small air bubbles are successively released from the bottom of the tank to generate a bubble plume, and a stirring disc at the bottom of the tank is rotated to impose a swirling water flow around the central axis of the bubble plume. The bubbles disperse further with the increasing rotational speedωof the stirring disc. Some bubbles shift toward the central axis of the swirling flow whenωis high. The nondimensional swirling velocity of water reduces with increasing bubble flow rate whenωis lower than a certain value. However, it is less affected by the bubbles whenωis higher. The precessional amplitude for the upper end of the vortex core increases due to the presence of the bubbles. With increasingω, the nondimensional precessional velocity decreases, and the bubble effect also reduces.