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Abstract  

Fullerences C60 with adamantane (C10H16), hexamethylotetramine (HMT, C6H12N4) or 1,4-diazabicyclooctane (DABCO, C6H12N2) crystallize, at the relative concentration C60/guest=2/1, in the pseudotetragonal lattice in which C60 retains almost the same positions as in pure fullerides. The ‘guest’ molecules occupy the octahedral interstitial sites. The mixed crystals which exhibit interesting physical properties are thermally unstable. The decomposition starts at 40–50°C.

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Abstract  

The11C and14C labeled fullerenes were produced by charged-particle and neutron irradiation, of C60, C70 and their mixture. It was found that a carbon atom of fullerence can be easily exchanged with a radioactive carbon atom produced by a nuclear reaction. The HPLC method was effective for identification and purification of various labeled fullerene families as chemically stable compounds. The radiochemically interesting aspect of the results is not only the production of11C and14C labeled fullerenes but also the formation of radioactive higher fullerenes which can be simultaneously produced with high yield and in carrier-free form.

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Amar, A., C.M. Hewson, R.M. Thewlis, K.W. Smith, R.J. Fuller, J.A. Lindsell, G. Conway, S. Butler and M. MacDonald. 2006. What’s happening to our woodland birds? Long-term changes in the populations of woodland birds. BTO Research Report 169 and RSPB

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. Andrology 1 , 644 – 650 . Füller , I. ( 2010 ): Further development of selection for meat production improvement in the Hungarian Fleckvieh cattle. PhD Thesis. http

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A field experiment was conducted to investigate the effect of soil application of zinc fertilizer on yield and yield components of wheat ( Triticum aestivum L. cv. Inqlab 91) grown on calcareous soil in Pakistan. The levels of zinc sulphate were 0 (control), 5, 10, 15, 20, 25 and 30 kg ha −2 and the zinc sulphate was combine-drilled at the time of sowing. Zinc sulphate increased the Leaf Area Index, the total number of fertile tillers m −2 , number of spikelets spike −2 , spike length, grain spike −2 , thousand grain weight, grain yield, straw yield and biological yield and decreased harvest index. Most of the response trends were curvilinear although the decrease in harvest index was linear. All applications of zinc sulphate gave economic increases in margins over costs but the application of 5 kg ha −2 gave the highest marginal rate of return. It is recommended that under such calcareous soil conditions growers can expect good returns from the application of 5 kg zinc sulphate ha −2 at the time of sowing but if the grain price were to increase or the price of zinc sulphate were reduced economic responses could be expected from higher levels of zinc sulphate.

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Abstract  

The Sr in plant and soil samples is converted to SrCl2 by digestion with HNO3 and HCl. The recovery of this digestion is 90% with a reproducibility of about 4%. SrCl2 is solubilized in toluene by forming a complex with di-n-propyl phosphate (DNP). The DNP-toluene reagent was found to be a highly effective carrier of SrCl2, and to have properties suitable for highly efficient liquid scintillation counting. An efficiency of 95% was obtained for89Sr counting. The factors affecting the utility of the method are discussed.

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Hubbell (2001) proposes that random demographic processes (i.e., neutral dynamics) can explain observed levels of variation in the richness and abundance of species within and among communities. Hubbell's neutral models have drawn attention because they reproduce several characteristic features of natural communities. But neutral models are criticized for ignoring nonrandom processes known to cause species densities to fluctuate. We parameterized neutral models using the population counts of 64 species of aquatic invertebrates collected from 49 discrete rock pools over a 13 year period.We used Hubbell's numerical modeling approach to evaluate the effect of natural population fluctuations on the parameter settings. We also analyzed the effect of observed variation on the species proportional abundance predicted by neutral models. We find that observed levels of variation in abundance are much higher than predicted by neutral models, forcing estimates of themigration probability, m, and fundamental biodiversity parameter, ?, to fluctuateover time. Much of the observed variation is mediated by predator-prey interactions. Low predator densities are associated with fewer species and less even relative abundances of species, resulting in lower estimates of m and ? comparedto periods of high predator densities. Our results show that by assuming an identical survival probability for all species, neutral models misrepresent substantial aspects of community dynamics.

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Absztrakt

Bevezetés: A váltott műszakban dolgozóknál gyakori probléma a megzavart diurnalis ritmus következtében kialakuló alvászavar. A Bergen Shift Work Sleep Questionnaire az alvásminőséget és hatásait vizsgálja különböző műszakok és szabadnapok esetén. Célkitűzés: A tanulmány célja e kérdőív magyar változatának kidolgozása, és alkalmazásával a különböző munkarendben dolgozó ápolók alvásminőségének összehasonlítása. Módszer: A kérdőívet 326, váltott műszakban dolgozó ápoló töltötte ki. A kérdőív konvergens és diszkrimináns validálása az Athéni Insomnia Skála és Észlelt Stressz Kérdőív segítségével történt. Eredmények: A kérdőív pszichometriai jellemzői alapján magyar mintán is alkalmas a váltott műszakkal összefüggő alvászavarok vizsgálatára. A diszkrét tünetek gyakorisága szignifikánsan (p<0,001) eltért a műszakok szerint. A legrosszabb alvásminőséget és nappali fáradtságot az éjszakai műszakot követően tapasztalták. A több műszakos, szabálytalan munkarendben dolgozók alvásminősége rosszabb, mint a szabályos és flexibilis munkarendben dolgozóké (p<0,001). Következtetések: A váltott műszakos ápolók alvásproblémáit a kidolgozott kérdőívvel célszerű országosan, reprezentatív mintán is megvizsgálni, és az eredmények alapján a legkevésbé megterhelő munkarendeket kialakítani. Orv. Hetil., 2015, 156(49), 2003–2009.

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Abstract

Paper sheets impregnated with flame retardants made from agricultural residues and other additives were studied with the cone calorimeter. The use of sugar beet ethanol eluent (SBE), CaCl2, and ZnCl2 lowered the peak rate of heat release (PRHR) the most in comparison to water treated material. The average effective heat of combustion (AEHC) was lowered by most of our treatments with the exception of BMIC (butylmethylimidazolium chloride)/starch (BMS). The average mass loss rate was lowered by all the treatments, but the most by the use of ZnCl2 and CaCl2 treatments. Mass losses were the least with SBE, CaCl2/NaOH/starch, and CaCl2/NaOH treatments. The BMS sample exhibited the greatest total heat release while SBE samples gave the smallest value of the parameter. The flame retarding effect of SBE was ascribed to the presence of ferulates which prevented the formation of volatile products by condensing into polycyclic aromatic residue.

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