12 research outputs found
Wild vascular plants gathered for consumption in the Polish countryside: a review
BACKGROUND: This paper is an ethnobotanical review of wild edible plants gathered for consumption from the end of the 18(th )century to the present day, within the present borders of Poland. METHODS: 42 ethnographic and botanical sources documenting the culinary use of wild plants were analyzed. RESULTS: The use of 112 species (3.7% of the flora) has been recorded. Only half of them have been used since the 1960s. Three species: Cirsium rivulare, Euphorbia peplus and Scirpus sylvaticus have never before been reported as edible by ethnobotanical literature. The list of wild edible plants which are still commonly gathered includes only two green vegetables (Rumex acetosa leaves for soups and Oxalis acetosella as children's snack), 15 folk species of fruits and seeds (Crataegus spp., Corylus avellana, Fagus sylvatica, Fragaria vesca, Malus domestica, Prunus spinosa, Pyrus spp., Rosa canina, Rubus idaeus, Rubus sect. Rubus, Sambucus nigra, Vaccinium myrtillus, V. oxycoccos, V. uliginosum, V. vitis-idaea) and four taxa used for seasoning or as preservatives (Armoracia rusticana root and leaves, Carum carvi seeds, Juniperus communis pseudo-fruits and Quercus spp. leaves). The use of other species is either forgotten or very rare. In the past, several species were used for food in times of scarcity, most commonly Chenopodium album, Urtica dioica, U. urens, Elymus repens, Oxalis acetosella and Cirsium spp., but now the use of wild plants is mainly restricted to raw consumption or making juices, jams, wines and other preserves. The history of the gradual disappearance of the original barszcz, Heracleum sphondylium soup, from Polish cuisine has been researched in detail and two, previously unpublished, instances of its use in the 20(th )century have been found in the Carpathians. An increase in the culinary use of some wild plants due to media publications can be observed. CONCLUSION: Poland can be characterized as a country where the traditions of culinary use of wild plants became impoverished very early, compared to some parts of southern Europe. The present use of wild plants, even among the oldest generation, has been almost entirely restricted to fruits
Some Problems in Quantitative Auger Analysis of Metallic Alloys
Factors determining the Auger signal intensity are discussed. It is indicated that using standards is the only reasonable way for quantitative Auger analysis (QAA). Approaches to QAA without and with matrix corrections are presented. It is shown that the matrix correction connected with atomic concentrations of pure standards is the most important and that the other matrix corrections (e.g. those connected with the attenuation length and backscattering factor) do not improve appreciably the QAA exactness in many examples taken from the literature. The examples indicate that in the case of metallic alloys the properly performed QAA gives the relative atomic concentrations with the error not exceeding few percent
Investigations of filtration and mechanical properties of PP capillary membranes
Konieczność ochrony środowiska oraz względy ekonomiczne kierują prace wielu badaczy w kierunku poszukiwania nowych sposobów zatężania, oczyszczania i rozdzielania różnych rodzajów mieszanin. Obecnie coraz chętniej w różnego rodzaju procesach wykorzystuje się membrany polimerowe. Praca prezentuje wyniki badań nad właściwościami filtracyjnymi i mechanicznymi membran kapilarnych z polipropylenu wykonanych na Wydziale Inżynierii Chemicznej i Procesowej Politechniki Warszawskiej.Necessity of environmental protection and economic reasons cause that researchers try to find new ways of densification, purification and separation. Nowadays, polymeric membranes are commonly used for this purpose. The paper presents results of research on filtration and mechanical properties of capillary membranes made at the Faculty of Chemical and Process Engineering, Warsaw University of Technology
Angular Distributions of Secondary Electrons Emitted from the Polycrystalline Silver
The angular distributions of secondary electrons (including Auger electrons) of different energies emitted from polycrystalline silver bombarded with primary electrons (E = 1000 and 2500 eV) were measured with a RFA analyzer equipped with an additional collector (acceptance angle ≈ 4°). Additionally, the angular distributions of primary electrons of different energies elastically backscattered from the same sample were also investigated by means of a specially constructed rotable RFA analyzer equipped with a channeltron. The results obtained show the cosine distribution of secondary and Auger electrons emitted as shown previously in the literature. The angular distributions of electrons backscattered elastically depend on electron energy and are in good agreement with theoretical calculations (Monte Carlo simulation of primary electrons trajectories in solids) proposed by Jabłoński
Determination of Inelastic Mean Free Path of Electrons in Noble Metals
The experimental values of Inelastic Mean Free Path (λ) of electrons in noble metals (Ag, Au, Cu) are determined in the electron energy range 150-2000 eV. The method used consists of the measurements and theoretical calculations of the coefficient of elastic backscattering of electrons from a solid surface η. The obtained values of λ are compared with the data available in the literature