Wyniki wyszukiwania - BazTech

1

Characterization of Site Conditions for Selected Seismic Stations in Eastern Part of Romania

Grecu B., Zaharia B., Diaconescu M., Bala A., Nastase E., Constantinescu E., Tataru D.

Acta Geophysica

|

2018

|

Vol. 66, no. 2

153--165

EN

Strong motion data are essential for seismic hazard assessment. To correctly understand and use this kind of data is necessary to have a good knowledge of local site conditions. Romania has one of the largest strong motion networks in Europe with 134 real-time stations. In this work, we aim to do a comprehensive site characterization for eight of these stations located in the eastern part of Romania. We make use of a various seismological dataset and we perform ambient noise and earthquake-based investigations to estimate the background noise level, the resonance frequencies and amplification of each site. We also derive the Vs30 parameter from the surface shear-wave velocity profiles obtained through the inversion of the Rayleigh waves recorded in active seismic measurements. Our analyses indicate similar results for seven stations: high noise levels for frequencies larger than 1 Hz, well defined fundamental resonance at low frequencies (0.15-0.29 Hz), moderate amplification levels (up to 4 units) for frequencies between 0.15 and 5-7 Hz and same soil class (type C) according to the estimated Vs30 and Eurocode 8. In contrast, the eighth station for which the soil class is evaluated of type B exhibits a very good noise level for a wide range of frequencies (0.0120 Hz), a broader fundamental resonance at high frequencies (~ 8 Hz) and a flat amplification curve between 0.1 and 3-4 Hz.

2

Oligonukleotydy DNA jako warstwy receptorowe sensorów elektrochemicznych

Górski Ł., Ziółkowski R., Bala A., Jarczewska M., Malinowska E.

Wiadomości Chemiczne

|

2015

|

[Z] 69, 5-6

325--336

EN

The need for elaboration of analytical devices of small dimensions and the accessibility of novel nanomaterials caused the increase in the number of publications referring to the development of biosensors. DNA-based biosensors are of special interest and they were primarily used for the determination of a specific sequence which is crucial in the detection of cancer, genetic mutations, pathogens, as well as analysis of modified food. Interestingly, they could be also applied for the detection of other analytes including heavy metal ions, especially in connection with electrochemical techniques. It should be noted that the design of DNA biosensor concerns not only the development of transducer, but also careful preparation of sensing layer and the choice of the method of analytical signal generation. Selectivity is one of the essential parameter of the biosensor that determines its utility, particularly in real samples of complex matrices. In case of DNA sensors dedicated for the detection of complementary sequence, high selectivity is provided by the hybridization process. A pronounced specificity of sensing layer-analyte interaction can be also achieved with the use of functional nucleic acids - aptamers, which change their conformation upon binding an analyte. Herein, DNA-modified electrodes were firstly used for the detection of uranyl ions, as they exhibit high affinity towards phosphate moieties of nuclec acids. It was shown that UO2 2+ interacts with sensing layer independently from the chosen oligonucleotide sequence. Moreover, the influence of Pb2+ was reduced by elimination of adenine, which strongly interacts with lead ions. Another oligonucleotide-based sensor was developed for detection of mercury ions. The results indicate that Hg2+ concentration can be determined only with the use of sequence containing 100% thymine residues. Oligonucleotide-based sensor with receptor layer containing aptamers was elaborated for the detection of Pb2+ ions. In the presence of lead cations, an aptamer probe forms a G-quadruplex structure, a proposed biosensor could be characterized with selectivity towards Pb2+ The performance of DNA-based sensors for UO2 2+, Hg2+ and Pb2+ ions was optimized and addressed the choice of the manner of analytical signal generation, the influence of electrode modification with blocking agent, sensitivity dependence on the oligonucleotide sequence and the possibility of regeneration of sensing layer. Finally, the utility of proposed DNA sensors was tested by analysis in real samples.

3

Możliwości zagospodarowania odpadu poprodukcyjnego biodiesla jako paliwa

Bala A., Radomiak H.

Ciepłownictwo, Ogrzewnictwo, Wentylacja

|

2012

|

T. 43, nr 9

365-368

PL

Podjęto problematykę zagospodarowania odpadu poprodukcyjnego biodiesla, tzw. frakcji glicerynowej. Przedstawiono możliwości zastosowania odpadu, jako paliwa ciepłowniczego. Podjęto próby spalania frakcji glicerynowej w otwartej przestrzeni i wygrzanej komorze ceramicznej. Frakcję współspalano z olejem opałowym lekkim, w różnych stosunkach wagowych. Badano wpływ zawartości frakcji glicerynowej w mieszaninie olej-gliceryna na wydajność palnika. Analizowano także wpływ udziału gliceryny na skład spalin, w tym na zawartość NOx.

EN

In the study, the possibility of the utilisation of waste glycerine (so called glycerine fraction) has been considered. In particular, the use of waste glycerine as heat-generation fuel has been tested. Glycerine fraction was combusted in an open space and in a warmed-up ceramic chamber. The glycerine fraction was also co-combusted with light fuel oil at different mass ratios. The effects of glycerine fraction content in the mixture of oil-glycerine on burner efficiency have been examined. The influence of glycerine fraction ratio in the mixture on fume gas composition, including NOx content, has also been analysed.