Search results for "Hopper"
showing 9 items of 49 documents
Normal pressures and frictional tractions on shallow conical hopper walls after concentric filling: Predictions and experiments
2013
Author's version of an article in the journal: Chemical Engineering Science. Also available from the publisher at: http://dx.doi.org/10.1016/j.ces.2012.11.028 A silo with a shallow hopper is designed to achieve the required silo capacity when the headroom available is limited, provided that the issue of segregation of stored particulate solids is not a problem. Several analytical models have been proposed to try to predict the design loads for such shallow silo hoppers to guarantee their structural integrity. In this study, a novel finite element analysis has been conducted to explore the development of pressures and tractions on the wall of a full scale shallow hopper when it is filled wit…
Scientific and methodical foundations of heat saving of rural territories on the basis of use of local biomass
2018
W ostatnich latach gaz ziemny na Ukrainie, a w szczególności w regionie połtawskim,wykorzystywany jest najczęściej do ogrzewania prywatnych domów. Niestety co roku państwo podnosi cenę gazu. Koszty ogrzewania stają się dla mieszkańców wsi dużym obciążeniem. Wcześniej na wsi tradycyjnie budowano domy o dużej powierzchni. Dlatego obecnie wspólnoty terytorialne szukają alternatywnych sposobów ogrzewania. W celu oszczędzania ciepła ważnymi dla nich stają się zagadnienia związane z izolacją budynków mieszkalnych, zakładów produkcyjnych. Głównym celem artykułu jest analiza możliwości wykorzystania biomasy jako materiału termoizolacyjnego oraz źródła energii alternatywnej. Przedstawiono doświadcze…
Edward Hopper, 50 ans après : influence et héritage
2019
International audience; Les textes rassemblés ici ont été présentés lors de la journée d’étude « Edward Hopper, 50 ans après : influence et héritage » organisée à l’université de Bourgogne par le Centre Interlangue TIL en avril 2017. Il s’agissait de s’interroger sur ce qui a assuré à la peinture d’Edward Hopper une telle pérennité et cette singulière capacité à s’imprégner dans la culture visuelle commune. Ce succès provient-il de l’absence de marques liées à son époque ? Est-il le fait d’un style aussi proche du réalisme que de l’abstraction invitant à une réflexion universelle sur la condition humaine ? S’explique-t-il par un contexte artistique plus favorable à l’émergence et à la promo…
In-Field LAMP Detection of Flavescence Dorée Phytoplasma in Crude Extracts of the Scaphoideus titanus Vector
2022
One of the most destructive diseases affecting grapevine in Europe is caused by Flavescence Dorée phytoplasma (FDp), which belongs to the 16Sr-V group and is a European Union quarantine pathogen. Although many molecular techniques such as loop-mediated isothermal amplification (LAMP) are widely used for the rapid detection of FDp in infected grapevine plants, there is no developed isothermal amplification assay for FDp detection in the insect vectors that are fundamental for the spread of the disease. For this reason, a simple in-field real-time LAMP protocol was optimized and developed for the specific detection of FDp in the insect vector Scaphoideus titanus. The LAMP assay was optimized …
Control of ovarian steroidogenesis in insects: A locust neurohormone is active in vitro on blowfly ovaries
2009
0016-6480 doi: DOI: 10.1016/j.ygcen.2009.04.034; Ovarian steroidogenesis controlling insect reproduction is mainly regulated by brain gonadotropins liberated from corpora cardiaca (CC). Till now, different neurohormones have been identified in two insect groups only, locusts and mosquitoes, and it is unknown whether they could be active in other insects. In order to complete previous observations on the control of ovarian steroidogenesis in the blowfly, Phormia regina, we examined whether neuropeptides isolated from locust CC have an effect in vitro on ovarian steroidogenesis in our dipteran model. Our experiments showed that crude extracts from locust CC efficiently stimulated steroidogene…
The toxic and lethal effects of the trehalase inhibitor trehazolin in locusts are caused by hypoglycaemia
2003
SUMMARY The main blood sugar of locusts is trehalose, which is hydrolysed to two glucose units by trehalase. Homogenates of locust flight muscles are rich in trehalase activity, which is bound to membranes. A minor fraction of trehalase is in an overt form while the remainder is latent, i.e. active only after impairing membrane integrity. Trehazolin, an antibiotic pseudosaccharide,inhibits locust flight muscle trehalase with apparent Ki-and EC50 values of 10–8 mol l–1and 10–7 mol l–1, respectively. Trehazolin is insecticidal: 50 μg injected into locusts completely and selectively blocked the overt form of muscle trehalase (with little effect on latent activity) and killed 50% of the insects…
Ideal types of online shoppers : a qualitative analysis of online shopping behavior
2018
Due to the growing popularity of online shopping, there is a growing demand for understanding the motives and behaviour of online shoppers. This study aims to increase this understanding by examining online shopping behaviour from the perspective of UTAUT2 theory integrated with self-efficacy and risk avoidance components. The thematically analysed data from 31 participants highlights the unique aspects of online shoppers by grouping them into ideal types, presenting the data as extensively as possible. An ideal type is an analytical construct used to ascertain similarities and deviations to concrete cases in an individual phenomenon. This study discovered five ideal types of online shopper…
Influenza delle infrastrutture ecologiche poste ai margini del vigneto su Empoasca vitis (Goethe) (Homoptera: Cicadellidae) e il suo parassitoide Ana…
2014
È ormai opinione diffusa che la diversità vegetale all’interno degli agrosistemi favorisca il mantenimento dell’entomofauna utile ai fini di un contenimento naturale di fitofagi. In quest’ambito, il presente lavoro ha riguardato uno studio, sulle popolazioni di Empoasca vitis e del suo parassitoide Anagrus atomus in un’azienda viticola sita nel comprensorio di Salemi (TP) (446 m s.l.m.) a conduzione biologica prendendo in considerazione due appezzamenti, uno con ai margini siepi di rovo, rosa canina e rosmarino e l’altro in assenza di siepi. Nel periodo vegeto-produttivo della vite (marzo-ottobre 2012), si è valutata l’influenza della specie vegetale e della variazione della distanza delle …
Habitat area and local habitat conditions outweigh fragmentation effects on insect communities in vineyards
2022
Fragmentation of habitat, for example by intensive agricultural practices, can be detrimental to local biodiversity. However, it often remains unclear whether such biodiversity declines are caused by loss of habitat area or increased fragmentation, and how habitat quality factors into it. In our study system, vegetated vineyards are typically small, and isolated from one another, potentially limiting the distribution and dispersal of organisms. In a full-factorial experiment of a priori selected vegetated vineyard patches of differing size and fragmentation, we aimed to disentangle the effects of habitat area (area of vegetated vineyards), habitat fragmentation (number of vegetated vineyard…