Authors:György Török, Mária Darányi, Tibor Alpár, and Ákos Kukovecz
Safety matches are at the very core of modern civilization, playing an unnoticed but vastly important part in everyday human activities since the middle of the 19th century. Although the general public is hardly aware of the strict and complex requirements that matches are expected to meet, it takes careful chemical engineering to control the match microstructure in a way that guarantees safe and reliable operation. In this contribution we summarize results obtained in this field by the cooperation of a match manufacturer and two Hungarian universities.
Authors:Yue Yao, Jianhong Wang, Yanyan Deng, and Jun Wang
microsphere containing nanocrystallites [ 26 ]. We further consider that this unusual morphology may cause the creation of uniformly distributed mesopores arising from the assembling of nanocrystallites, which seems favorable to the hydroisomerization of n
Authors:B. Bhattacharjya, H. Dutta, K. Patwari, and C.L. Mahanta
Jackfruit seed starch was annealed by single stage and double stage processes and characterised for changes in properties. Single-stage annealing gave higher crystalline order than double-stage annealed starch. No major change in the granular morphology was observed. Annealing resulted in notably altered pasting properties. Increased peak viscosity was indicative of molecular rigidity developed in the granules due to annealing. The increased thermal stability in DSC and specific peak sharpening in the XRD patterns of single-stage annealed starches indicated development of ‘site specific’ crystallinity. The new crystallites formed during the first stage of double-stage annealing were heat labile as crystallinity lowered after the second stage. Single stage annealed jackfruit seed starch can be used for noodle making.
Authors:B. Cserháti, K. Juhos, A. Begyik, P. Radácsi, É. Németh, and K. Szabó
Wild Origanum vulgare populations in Hungary have been analysed. In 2010 the morphological variability of 11 populations in five shires was investigated, the features of habitats were also described. The difference in elevation between the lowest and highest locality is 630 m. Nine plant associations, four soil types, variable pH between 4.81–7.96 and humus content from 0.54% to 6.97% were determined. Among the examined individual plants the maximum length of stem was 107 cm, the highest number of branches was 14 pairs, furthermore procumbent and mellow stems were also found. The defined colours of inflorescences are dyes of pink or purple. Despite to these we found individuals in one population with white flowers, green bracts and calyces.
Noble rot of the grape is a complex microbiological-biochemical process having grate importance in the Tokaj wine district. In this study, morphology and development of Botrytis cinerea in the berry skin as well as the presence of other moulds and yeasts on the digested exocarp of the noble rotted grapes (aszú) were investigated and presented by scanning electron microscopy. Another aim of this work was a comprehensive taxonomical characterisation of the yeasts present on the surface of the “aszú” berries in the Tokaj wine district in five vintage years. The dominant yeasts were isolated and taxonomically identified according to phenotypical properties. The most prevalent yeast species of the aszú grapes were Metschnikowia pulcherrima in the vineyard and Candida stellata in the winery (the latter species has been recently differentiated for two species, C. stellata and C. zemplinina). These two Candida species seem to be typical yeasts of Tokaj aszú berries, particularly after picking, transporting and storage of the aszú grape. These postharvest operations significantly influence mould and yeast populations of botrytized grapes.
, Miranda, I.P.A.
, Moura, C.O.
, Rabelo, A.
& Barbosa, E.M.
(2002): Características morfológicas e bioquímicas do pólen coletado por cinco espécies de Meliponíneos da Amazônia Central. (Morphological and biochemical characteristics of pollen
Authors:M. Petróczy, Gy. Csejk, É. Pájtli, and L. Palkovics
In May 2011, young Impatiens walleriana Hook. f. plants showing downy mildew symptoms were collected from a greenhouse (Kecskemét, Hungary). The upper surface of affected leaves turned yellow and white fungal-like growth was observed on the underside. Diseased plants wilted and rapidly collapsed, resulting in losses of nearly 100%. Downy mildew of impatiens can be caused by two pathogens, Plasmopara obducens or Plasmopara constantinescui (syn: Bremiella sphaerosperma), which can be distinguished by the symptoms and by morphology of sporangiophores and sporangia. For molecular identification the 5′-end of the large subunit of ribosomal RNA gene was amplified by PCR using NL1 and NL4 primers and cloned and sequenced. The nucleotide sequence of the Hungarian isolate showed highest identity (99.72%) with two isolates of Plasmopara obducens from the United Kingdom and Serbia. On the basis of the symptoms, molecular and morphological characters, the pathogen was identified as P. obducens. The appearance of the pathogen in Hungary seriously endangers the production of I. walleriana, which is a popular ornamental in gardens and city parks. The chemical plant protection is not effective against the pathogen, by the occurrence of the first symptoms the diseased plants should be removed from the plantlet and must be destroyed.
Multiwall carbon nanotubes were synthesized either on the outer surface of iron containing mesoporous silicates using catalytic chemical vapor deposition (CCVD) or in the pore system of morphologically different mesoporous materials (hexagonal or spherical shapes) with graphitization of the template molecules. Transmission electron microscopy (TEM) study shows that the CCVD method resulted in long, bent and well graphitized carbon nanotubes on impregnated samples irrespective to the morphology of the silicate. Isomorphously substituted spherical MCM-41 with low Si/Fe ratio was found to be active catalysts for carbon nanotube production in CCVD as well. Synthesis of MWNTs with graphitization of template molecules in the pores of MCM-41 was successful in hexagonal MCM-41 samples irrespective that they contain or not iron in the silicate framework. Carbon nanotube formation was not observed in spherical derivatives of these samples during the graphitization process.
The application of ultrasound during extraction of oil from apricot kernels using hexane was evaluated and compared with conventional methods (mechanical extraction and Soxhlet extraction). Results show that ultrasound assisted extraction (UAE) yields more oil with less solvent consumption. The oil yield from UAE, SE, and ME were 44.72%, 44.33%, and 35.06%, respectively. It is noteworthy that it took 44 min to extract oil by UAE method, while alike yield was obtained from SE in 6 hours. Oil extracted by UAE exhibited significantly higher peroxide and ester values. The functional groups of apricot kernel oil were analysed using Fourier transform infrared spectroscopy. Untreated and treated kernel powders were studied by scanning electron microscopy, and the development of microstructures and disruption of cell walls were evaluated. Our study suggests that ultrasound assisted extraction may be an effective method to extract edible oils by achieving higher efficiency in shorter extraction time.
The photocatalytic properties of MoS2 samples including nano-ball, nano-slice and bulk 2H-MoS2 were evaluated and compared with that of the anatase TiO2 using the degradation reaction of methyl orange under visible light. The catalytic behaviors of the samples were also characterized
using transmission electron microscopy, Brunauer-Emmett-Teller (BET) surface area, ultraviolet-visible spectroscopy, and FTIR
spectroscopy. The results show that the bulk MoS2 and the anatase TiO2 were almost inactive under visible light. The nano-slice presented the most positive catalytic effect because it has a wide
absorption at 400–700 nm and a high BET surface area. Though the BET surface area of the nano-ball was lower than that of
the nano-slice, it has an active curved basal surface and presented a catalytic activity close to that of the nano-slice.
Moreover, the MoS2 nano-slice catalyst could be conveniently regenerated after filtration and drying.