28 research outputs found
Primer synovialis chondromatosis a bokaízületben = Primary synovial chondromatosis in the ankle joint
Optimizing the combustion processes of a small scale solid fuel-fired boiler
Over the last decade, the public has been paying increasing attention to reducing greenhouse gas and acid rain emissions and reducing particulate matter, which is extremely harmful to health and the environment. To improve air quality, the European Commission has achieved a range of measures to reduce air pollutant emissions in the transport, heat and electricity, industrial and agricultural sectors. In Hungary, the amount of gas and solid air pollutants from solid fuel combustion used by the public during the heating season represents a significant percentage of the total amount present in the atmosphere. In 2016, taking into the total emission, the 29% of CO2 emissions; 85% of CO emissions; 75% of the particulate matter emissions and 21% of the NOx emissions were derived from households. It follows that the improvement of air quality can also be achieved by controlling the emissions of solid fuel combustion plants. During our research we aimed to optimize the operation of a newly purchased TOTYA S18 boiler and a pilot pellet boiler. Operating the boilers in the correct mode minimizes air pollutant emissions, and the greater part of the heat generated is actually turns to heating the home, as with poor settings, a lot of heat leaves through the chimney. The data obtained during the tests can also be used to determine whether the boilers comply with the emission values set out in Commission Regulation (EU) 2015/1185
The dissolved organic matter as a potential soil quality indicator in arable soils of Hungary
Iskolás- és serdülőkorúak droghasználata: kockázati és védő faktorok egy reprezentatív vizsgálat tükrében
Absztrakt
Elméleti háttér: A drogok használatának széles körű
elterjedtsége és a kipróbálás egyre korábbi időpontra kerülése miatt napjaink
fontos kutatási célja a szerekhez kapcsolódó rizikó- és védő faktorok
azonosítása. Az „Iskolai Egészségfejlesztés és Univerzális Drogmegelőzés” (IEUD)
elnevezésű kutatást a Nemzeti Család- és Szociálpolitikai Intézet
kutatócsoportja indította. Reprezentatív adatok alapján hiteles képet kívántunk
nyerni a 6—18 éves iskolás generáció mentálhigiénés állapotáról, ezen belül a
szerhasználatról (dohányzás, alkohol- és kábítószer-fogyasztás), a kockázati
tényezőkről, illetve a védő (preventív, protektív) faktorokról. Elemzésünkben
elsősorban a szerek kipróbálásának és használatának környezeti-kapcsolati
összefüggéseit tártuk fel. Módszerek: A vizsgálatban 7623, 1.,
3., 5., 7., 9. és 11. osztályos tanuló vett részt. Kérdőíves (tanórai)
adatfelvételt végeztünk egy olyan komplex tesztbattériával, amely a
szerhasználati szokásokon kívül rákérdezett a kapcsolati mintákra és modellekre,
felmért továbbá számos pszichés faktort (pl. Big Five személyiségjegyek,
deviancia, hangulati változók). Eredmények: A szerfogyasztási
mutatók a Magyarországon készült korábbi reprezentatív vizsgálatok eredményeihez
hasonlóan alakultak. A Globális Szerhasználati Mutató mintegy 51 százalékát
lehet pszichoszociális változókkal magyarázni, ezen belül erősen meghatározónak
találtuk a devianciát, az anyai nevelést, a családból és kortárs közösségből
származó modelleket, egyes személyiségjegyeket (pl. extraverzió, neuroticizmus)
és a másik nem körében való észlelt népszerűséget.
Következtetések: Vizsgálatunk tanulságait a drogprevenció
célkitűzéseinek és módszereinek kijelölésénél lehet alkalmazni. Álláspontunk
szerint a célzott prevenció során fokozott figyelemmel kell kísérni a deviáns
magatartásra veszélyeztetett csoportokat; továbbá egyes kockázatot jelentő
személyiségjegyekkel bíró (pl. érzelmileg labilisabb) serdülőket. Adataink
tükrében ígéretes eredményeket hozhatnak a családra fókuszáló, például szülői
monitoring technikákat erősítő és a kortárscsoportokat bevonó intervenciók
Szén nanocső jellegű nanoszerkezetek előállítása, módosítása és jellemzése fizikai, kémiai és szimulációs módszerekre alapozva = Production, modification and characterization by physical, chemical and computer simulation of carbon nanotube type nanostructures
Kimutattuk, hogy a nem-hatszöges (n-H) gyűrűket is tartalmazó szén nanoszerkezetek (Y-elágazás, hengerspirálok, stb.) növekedését az n-H gyűrűk beépülésének mikéntje határozza meg, új modellt javasoltunk hengerspirálok szerkezetére. Elsőként készítettünk Si3N4/szén nanocső kompozitokat és megmutattuk, hogy megfelelő szinterelési paraméterek alkalmazásával megőrizhetők az elektromosan vezetővé tett mátrix jó tulajdonságai. Új nanocső növesztési módszereket dolgoztunk ki. Elsőként bizonyítottuk, hogy az ionos besugárzás nyomán a szén nanocsöveken, valóban a szimulációknak megfelelő topográfiai alakzatok jelennek meg. Elméleti modellt adtunk a hibák környezetében azt STM felvételeken megfigyelhető szuperstruktúrák eredetére. Megmutattuk, hogy a funkcionalizálás módjától függően a funkciós csoportok szigetszerűen, vagy folytonoshelyezkednek el. A funkciós csoportok megváltoztatják a nanocsövek válaszjelét a környezetben jelenlévő gázokra/gőzökre. Sikeresen fejlesztettünk elméleti módszereket a gyengén kölcsönható nagy atomszámú rendszerek leírására és elsőkként vizsgáltuk sok szén nanocsöből felépülő kötegekben a csövek egymással való kölcsönhatását. Első elvekre illetve sűrűségfunkcionál módszerre alapozva vizsgáltuk a duplafalú szén nanocsövek, illetve a nanocsőben elhelyezkedő szénláncok tulajdonságait. A sajátfejlesztésű hullámcsomagdinamikai módszerünkkel elsőkként vizsgáltuk az elektronhullámok terjedését szén nanocső Y elágazásokban. | We showed that the growth of carbon nanostructures containing non-hexagonal (n-H) rings (Y-branches, coils etc.) is determined by the incorporation of the n-H rings, we proposed a new model for the structure of regularly coiled carbon nanotubes. We prepared the first Si3N4/carbon nanotube composites and we showed the under proper sintering conditions the composite can be made conductive while keeping the remarkable properties of the matrix. We developed new growth methods for carbon nanotubes. We showed for the first time that ion irradiation of carbon nanotubes indeed creates the features predicted by simulations. We proposed a theoretical description of the superstructures observed in STM in the vicinity of the defects. Depending on the way in which the functionalization is done, the functional groups appear on the nanotubes in an island-like or a continuous fashion. Their presence influences the response of the carbon nanotubes to the gases/vapors present in the atmosphere. We developed successfully theoretical tools for the description of weakly interacting large system and investigated for the first time the interaction of tubes in carbon nanotube bundles containing many tubes. Based on first principle and density functional calculations we investigated the double wall carbon nanotubes and linear carbon chains located inside a SWCNT. Using our own wave packet dynamical software we investigated the propagation of electronic waves in carbon nanotube Y junctions
Virus and bacterial removal ability of TiO2 nanowire-based self-supported hybrid membranes
Development and application of hybrid membranes containing multi-component materials are increasing day by day in the fields of environmental protection and water treatment. In this research, the efficiency of titania nanowire (TiO2 NW)-based self-supported hybrid membranes was investigated in the removal of Escherichia coli (E. coli) bacteria and MS2 bacteriophages from contaminated water mimicking the microorganism suspension. Furthermore, toxicology tests on the as-prepared membranes were also performed. TiO2 NWs were coated with iron(III) oxide (Fe2O3) and copper(II) oxide (CuO) nanoparticles, respectively, and cellulose was used as reinforcement material. It was found that, the functionalisation strongly affected the MS2 removal ability of as-prepared membranes, which can be due to the electrostatic interactions between the surface of hybrid membrane and the bacteriophages. The most efficient removal (greater than or equal to 99.99%) was obtained with the TiO2 NW-CuO-cellulose membrane at pH 7.0. The fabricated hybrid membranes were characterized by micro computed tomography (μCT), Raman spectroscopy, Fourier transform infrared spectroscopy (FT-IR), dynamic light scattering (DLS), contact angle measurement and inductively coupled optical emission spectrometry (ICP-OES) techniques. This study shows a simple route of the usage of novel and effective inorganic nanowire-based hybrid membranes for bacteria and virus removal, providing new pathways in the field of water filtration technologies
Composite Carbon Foams as an Alternative to the Conventional Biomass-Derived Activated Carbon in Catalytic Application
The suitability of a new type of polyurethane-based composite carbon foam for several possible usages is evaluated and reported. A comparison of the properties of the as-prepared carbon foams was performed with widely available commercial biomass-derived activated carbon. Carbon foams were synthesized from polyurethane foams with different graphite contents through one-step activation using CO2. In this work, a carbon catalyst was synthesized with a moderately active surface (SBET = 554 m2/g), a thermal conductivity of 0.09 W/mK, and a minimum metal ion content of 0.2 wt%, which can be recommended for phosgene production. The composite carbon foams exhibited better thermal stability, as there is a very little weight loss at temperatures below 500 °C, and weight loss is slower at temperatures above 500 °C (phosgene synthesis: 550–700 °C). Owing to the good surface and thermal properties and the negligible metallic impurities, composite carbon foam produced from polyurethane foams are the best alternative to the conventional coconut-based activated carbon catalyst used in phosgene gas production
Modulated Electro-Hyperthermia Accelerates Tumor Delivery and Improves Anticancer Activity of Doxorubicin Encapsulated in Lyso-Thermosensitive Liposomes in 4T1-Tumor-Bearing Mice
Modulated electro-hyperthermia (mEHT) is an adjuvant cancer therapy that enables tumor-selective heating (+2.5 °C). In this study, we investigated whether mEHT accelerates the tumor-specific delivery of doxorubicin (DOX) from lyso-thermosensitive liposomal doxorubicin (LTLD) and improves its anticancer efficacy in mice bearing a triple-negative breast cancer cell line (4T1). The 4T1 cells were orthotopically injected into Balb/C mice, and mEHT was performed on days 9, 12, and 15 after the implantation. DOX, LTLD, or PEGylated liposomal DOX (PLD) were administered for comparison. The tumor size and DOX accumulation in the tumor were measured. The cleaved caspase-3 (cC3) and cell proliferation were evaluated by cC3 or Ki67 immunohistochemistry and Western blot. The LTLD+mEHT combination was more effective at inhibiting tumor growth than the free DOX and PLD, demonstrated by reductions in both the tumor volume and tumor weight. LTLD+mEHT resulted in the highest DOX accumulation in the tumor one hour after treatment. Tumor cell damage was associated with cC3 in the damaged area, and with a reduction in Ki67 in the living area. These changes were significantly the strongest in the LTLD+mEHT-treated tumors. The body weight loss was similar in all mice treated with any DOX formulation, suggesting no difference in toxicity. In conclusion, LTLD combined with mEHT represents a novel approach for DOX delivery into cancer tissue
Preparation and Photocatalytic Performance of TiO2 Nanowire-Based Self-Supported Hybrid Membranes
Nowadays, the use of hybrid structures and multi-component materials is gaining ground in the fields of environmental protection, water treatment and removal of organic pollutants. This study describes promising, cheap and photoactive self-supported hybrid membranes as a possible solution for wastewater treatment applications. In the course of this research work, the photocatalytic performance of titania nanowire (TiO(2) NW)-based hybrid membranes in the adsorption and degradation of methylene blue (MB) under UV irradiation was investigated. Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray powder diffractometry (XRD) were used to study the morphology and surface of the as-prepared hybrid membranes. We tested the photocatalytic efficiency of the as-prepared membranes in decomposing methylene blue (MB) under UV light irradiation. The hybrid membranes achieved the removal of MB with a degradation efficiency of 90% in 60 min. The high efficiency can be attributed to the presence of binary components in the membrane that enhanced both the adsorption capability and the photocatalytic ability of the membranes. The results obtained suggest that multicomponent hybrid membranes could be promising candidates for future photocatalysis-based water treatment technologies that also take into account the principles of circular economy
Synthesis of activated carbon foams with high specific surface area using polyurethane elastomer templates for effective removal of methylene blue
Carbon foams have gained significant attention due to their tuneable properties that enable a wide range of applications including catalysis, energy storage and wastewater treatment. Novel synthesis pathways enable novel applications via yielding complex, hierarchical material structure. In this work, activated carbon foams (ACFs) were produced from waste polyurethane elastomer templates using different synthesis pathways, including a novel one-step method. Uniquely, the produced foams exhibited complex structure and contained carbon microspheres. The ACFs were synthesized by impregnating the elastomers in an acidified sucrose solution followed by direct activation using CO2 at 1000 ℃. Different pyrolysis and activation conditions were investigated. The ACFs were characterized by a high specific surface area (SBET) of 2172 m2/g and an enhanced pore volume of 1.08 cm3/g. Computer tomography and morphological studies revealed an inhomogeneous porous structure and the presence of numerous carbon spheres of varying sizes embedded in the porous network of the three-dimensional carbon foam. X-ray diffraction (XRD) and Raman spectroscopy indicated that the obtained carbon foam was amorphous and of turbostratic structure. Moreover, the activation process enhanced the surface of the carbon foam, making it more hydrophilic via altering pore size distribution and introducing oxygen functional groups. In equilibrium, the adsorption of methylene blue on ACF followed the Langmuir isotherm model with a maximum adsorption capacity of 592 mg/g. Based on these results, the produced ACFs have potential applications as adsorbents, catalyst support and electrode material in energy storage systems