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Authors give a report on four eriophyoid species which were new for the Hungarian fauna (Aculops berochensis Keifer and Delley; Aculops parakarensis Bagdasarian; Aculus ligustri Keifer; Aculus? crataegumplicans Cotte). Three of them were found on new host-plants.

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Aculodes dubius (Nalepa), Aculodes mckenziei (Keifer) and Aceria tosi­chella Keifer were recorded for the first time in Hungary. Festuca praten­sis, Phleum phleoides and Bromus inermis were found as new host-plants of Aculodes dubius, althought other plant species in these generas are known to be hosts of this mite. Aceria tulipae (Keifer) was indentified on Phleum pratense and Aceria tenuis (Nalepa) on Phleum phleoides, which were also new host-plants for them.

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Study of the mechanism of optical resolutionsvia diastereoisomeric salt formation

V. Thermoanalytical investigation of the optical resolution of the N-methylamphetamine by tartaric acid

Journal of Thermal Analysis and Calorimetry
Authors:
D. Kozma
,
C. Novák
,
G. Pokol
, and
E. Fogassy

The products obtained in the optical resolution of the N-methylamphetamine by the Pope-Peachy method, using half equivalent R, R-tartaric acid and half equivalent hydrochloric acid in absolute ethanol were investigated by thermoanalytical methods. The DSC measurements of the precipitated salts provide sufficient information for following the progress of the resolution. In this way, the results of the resolution can be estimated with the precision of about 5% optical purity.

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Abstract

In our days, energy issues belong to the most important problems facing the Earth and the solution may be expected partly from decreasing the amount of the energy used and partly from the increased utilisation of renewable energy resources. A substantial part of energy consumption is related to buildings and includes, inter alia, the use for cooling/heating, lighting and cooking purposes. In the view of the above, special attention has been paid to minimising the energy consumption of buildings since the late 1980s. Within the framework of that, the passive house was created, a building in which the thermal comfort can be achieved solely by postheating or postcooling of the fresh air mass without a need for recirculated air.

The aim of the paper is to study the changes in the construction of passive houses over time. In addition, the differences between the geographical locations and the observable peculiarities with regard to the individual building types are also presented.

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The aim of this paper is to provide an overview of the tendencies of development in the construction industry, one of the most important foundations of economic development, between 2000 and 2012. The key findings of the study may be summarized in the following:

– In the period between the 2000 and 2012, after the increasing tendency that could be observed in the first half of the first decade in the new millennium, a significant drop occurred both in terms of the value of production and the number of employees in the construction industry.

– From the three subsectors of the construction industry, it was the construction of buildings on which the economic crisis that started in 2008 had a negative impact.

– The territorial tendencies of the construction industry were influenced by large-scale infrastructural investments (motorway construction, railway network development).

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Abstract  

The enantioselectivity of the diastereomeric supramolecular compound (SMC) formation between O,O'-dibenzoyl-(2R,3R)-tartaric acid (DBTA) and chiral secondary alcohols was investigated. On the basis of TG measurements the DBTA:chiral alcohol molar ratio in the SMC-s is nearly 1:1. Among the investigated complexes the most stable SMC is trans-2-iodo-cyclohexanol-DBTA. The SMC forming capability and the enantioselectivity depends on the space filling of the alcohol side chain or ring. In the case of trans-2-halogen-cyclohexanols a relationship can be observed between the thermal stability of the SMC-s and the enantioselectivity of SMC forming.

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Abstract  

The optical resolution of racemic mandelic acid (I) by S-2-benzylamino-butanol (II) was performed in water, ethyl acetate, and water saturated ethyl acetate. It was found that the efficiency of the resolution is three times higher in water saturated ethyl acetate than in either water or ethyl acetate. The salt mixtures produced during the resolutions and the pure diastereoisomeric salts were analyzed by TG, DSC and X-ray powder diffraction measurements. The R-(-)-IS-(+)-II salt has the higher melting point and heat of fusion value which indicates that this is the more stable salt. Though the general assumption is that diastereoisomeric salt pairs of successful optical resolutions form eutectic systems, the R-mandelic acid-S-2-benzylamino-butanol and the S-mandelic acid-S-2-benzylamino-butanol system was found to behave in a different way. Melting did not start at or near the estimated eutectic temperature. The difference can be explained either by miscibility in the solid phase (solid solution) or by a blocked interaction between the crystals of the two solid salts. This unusual behaviour of the salt pair should be responsible for the unusual difference in the efficiency of the resolutions performed in different solvents

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Abstract  

Chiral drugs are generally resolved through formation of diastereoisomeric salts of different solubility. When the diastereoisomer salts from a eutectic in the solid phase, a good estimate can be made for the efficiency of the resolution (S), through a calculation based on the eutectic composition (x eu). The eutectic composition can be computed from thermal data of a differential scanning calorimetric (DSC) measurement of the diastereoisomeric salts [1]. In this work we investigated the influence of uncertainties of thermal data on the estimation of the efficiency of resolution (S), spreading throughout the calculations involved. Performance of our error-estimating method is demonstrated on 6 diastereoisomer salt pairs. The obtained deviations are close to the deviations of resolution experiments. Thus, it can be concluded that the DSC measurements are useful means in predicting the efficiency of resolutions.

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Abstract  

The diastereoisomeric salt pair formed between α-phenyl-ethyl-amine and R-1-phenylethylsuccinamic acid were investigated by physico-chemical methods. Melting and solubility phase diagrams were determined, the coincidence of the eutectic points of the two phase diagrams were demonstrated. The large difference in physico-chemical properties of the salt pair explains the efficient enantiomer separation.

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Study of the mechanism of optical resolutions via diastereoisomeric salt formation

2. Thermoanalytical and X-ray study of solid solution formation during the resolution of racemic malic acid by R-α-phenylethylamine

Journal of Thermal Analysis and Calorimetry
Authors:
D. Kozma
,
Klára Tomor
,
C. Novák
,
G. Pokol
, and
E. Fogassy

Racemic malic acid (I) was resolved by R-α-phenylethylamine(II). The S-(−)-I.R-(+)-II diastereoisomer was in excess in the precipitated salt. DSC curves and X-ray powder diffractograms proved that the diastereoisomeric salt mixture precipitated during the resolution was isomorphous with the optically pure S-(−)-I.R-(+)-II salt. The diastereoisomeric salt mixture containing the R-(−)-I.R-(+)-II salt in abundance bound crystal solvate (water or methanol) when produced by the total evaporation of the mother liquor, while the optically pure R-(−)-I.R-(+)-II salt crystallized without solvate. It is generally assumed that solid solution formation takes place when the two diastereoisomers are alike and the high similarity results in less efficient enantiomer separation.

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