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Dimensional encapsulation of I− I 2 I− in an organic salt crystal matrix
2010
Bis(trimethylammonium)hexane diiodide encapsulates iodine from solution and through a gas/solid reaction yielding in a predictable and controllable manner the selective formation of the rare polyiodide species I(-)...I-I...I(-), which matches in length to the chosen dication.
Termomodernizacje budynków, a miejsca lęgowe chronionych gatunków ptaków - zagrożenie czy szansa?
2017
Teoretycznie prace związane z termoizolacją budynków, szczególnie bloków mieszkalnych, powinny zostać poprzedzone ekspertyzą ornitologiczną. Nawet jeśli takowa będzie miała miejsce, montowane budki lęgowe kompensujące utratę miejsc lęgowych dla takich gatunków jak wróbel (Passer domesticus) lub jerzyk (Apus apus) często wieszane są nieprawidłowo lub zasiedlone są w następnym sezonie przez inne dziuplaki - głównie szpaki (Sturnus vulgaris). Wobec tego, z punktu widzenia ochrony lęgowych i zagrożonych gatunków, termoizolacja jest uważana za szkodliwą i przynoszącą straty. Jednak w miarę upływu czasu,paradoksalnie, warstwa izolacyjna stwarza ponownie warunki do gniazdowania głównie dzięki nied…
Diastereomeric control of enantioselectivity: evidence for metal cluster catalysis
2014
Enantioselective hydrogenation of tiglic acid effected by diastereomers of the general formula [(μ-H)2Ru3(μ3-S)(CO)7(μ-P–P*)] (P–P* = chiral Walphos diphosphine ligand) strongly supports catalysis by intact Ru3 clusters. A catalytic mechanism involving Ru3 clusters has been established by DFT calculations. peerReviewed
Simulation of Fatigue Delamination Growth in Composites with Different Mode Mixtures
2007
A numerical model, obtained by implementing a cyclic damage model in the framework of an interface element, is here proposed to reproduce the crack growth in laminated composites subjected to cyclically repeated loads. This model, which differs from the few studies in the literature on the topic, applies not only to single fracture modes but also to mixed modes, and to constant or variable crack growth rates. The applied load (in terms of force or displacement) is assumed to oscillate between a minimum and a maximum constant value. The Paris curve can be reproduced with accuracy once some parameters in the numerical model are tuned with experiments. These parameters are preliminarily found…
Breeding near heterospecifics as a defence against brood parasites: can redstarts lower probability of cuckoo parasitism using neighbours?
2022
Breeding habitat choice based on the attraction to other species can provide valuable social information and protection benefits. In birds, species with overlapping resources can be a cue of good quality habitats; species with shared predators and/or brood parasites can increase joint vigilance or cooperative mobbing, while raptors may provide a protective umbrella against these threats. We tested whether the migratory common redstart (Phoenicurus phoenicurus) is attracted to breed near active nests of the great tit (Parus major), a keystone-information source for migrant passerine birds, or a top predator, the northern goshawk (Accipiter gentilis). This system is unique to test these quest…
Glochidia Infection of Endemic Fishes from Lake Prespa, N. Macedonia
2022
Large freshwater mussels (Unionida) are long-lived, have large bodies, and produce thousands to millions of larvae (glochidia) that usually must attach to host fish tissue to complete their life cycle. This is an obligate parasitic stage of mussel larvae. However, less than one in onemillion find a suitable host and survive. The degree of host specificity varies among unionid species, from specialists that can successfully parasitize only one or a few closely related fish species to generalists that can complete development on a taxonomically broad range of fish species. In addition, freshwater mussels are among the most threatened groups of animals. This is due to habitat destruction, the …
The S … Hal and Se … Hal chalcogen bonding in a series of thiourea, selenourea and their derivatives
2021
The chalcogen bonding (ChB) in a series of thiourea, selenourea and their derivatives has been investigated in the present paper. Thus, selenourea and dimethylselenourea undergo dimerization and trimerization processes in the presence of various halogen species (1–5). Selenourea and dimethylselenourea form trimers 3–4 in the presence of lighter halogens (chlorine and bromine) through Se⋯Se chalcogen bonding. When moving to heavier halogen (iodine), the dimers 1–2 are formed. Thiourea and its derivatives also tend to make very strong S⋯S bonds and form dimers in the case of lighter halogens chlorine and bromine (compounds 6–7). However, the monomers separated by the iodine species are formed…
Tetracyclic silaheterocycle formed through a pericyclic reaction cascade including a two-fold intramolecular C–C bond activation
2022
Reductive debromination of the tribromoamidosilane 2 gave the tetracyclic silaheterocycle 3 through a unique reaction cascade involving unprecedented two-fold intramolecular cycloaddition by transient silylenes. Experimental and computational analyses of the reaction mechanism allowed the identification of the key intermediates that lead to the silaheterocycle 3 or, alternatively, to the cyclotrisilene 19. peerReviewed
Nesting behaviour and description of mature larva of Lindenius albilabris (Fabricius, 1793) (Hymenoptera: Crabronidae)
2022
Nesting habits of the digger wasp Lindenius albilabris (Fabricius, 1793) at two localities in Poland were studied. The female hunts nymphs or adults of plant bugs Lygus rugulipennis Poppius, 1911 and L. pratensis (Linnaeus, 1758), depositing up to 10 individuals per cell, depending on their size. Nests are built in a wide variety of sandy habitats, on dirt roads, and in wastelands. The nest consists of a 10–12 cm long main burrow and one to three cells. Males are usually found on flowers of wild carrots Achillea millefolium, Daucus carota, Peucedanum oreoselinum, Pimpinella sp. and Tanacetum vulgare. The nest kleptoparasite Metopia argyrocephala was recorded in nests of this species. The ma…
A land of mystical beauty, living wonder and unrivalled adventure : representation of New Zealand through adventure tourism websites
2009
Matkailu on yksi suurimmista elinkeinoista maailmassa, ja se on kasvanut huomattavalla vauhdilla viimeisten vuosikymmenten aikana. Myös Uudessa-Seelannissa matkailu on yksi maan tärkeimmistä elinkeinoaloista ja työllistäjistä. Uudesta-Seelannista löytyy useita erilaisiin aktiviteetteihin erikoistuneita matkailuyrityksiä. Seikkailumatkailulla on merkittävä rooli matkailussa, esimerkiksi benji-hypystä on tullut yksi maan matkailuikoneista. Tässä tutkimuksessa keskiössä oli seikkailumatkailun rooli Uuden- Seelannin matkailullisen imagon luomisessa. Internet tarjoaa nykypäivänä tärkeän markkinointikanavan, erityisesti matkailuyrityksille. Matkailuesitteiden määrä ja merkitys on vähentynyt huom…