Critical Gap in Roundabouts – A Short Comparison of Estimation Methods

Gap-acceptance method is one of the classical methods used to analyze the capacity of roundabouts. Critical gap has a privileged role in this approach. Different driver behavior and local rules of traffic have key role in implementing gap-acceptance method into the local standard for capacity calculation in each country. Therefore, a reliable method for estimation of critical gap at a certain location can be of great importance. This paper presents an experimental investigation and analysis on whether it is possible to find differences between estimating critical gap using video-based gap acceptance data of roundabouts in Hungary. Three single lane roundabouts of different size were recorded for hours in different locations in Budapest and Érd to assess gap acceptance data. Three different methods or models were used to estimate critical gap and no significant differences were found between their results

Cu and Cu2In nanoparticles supported on amorphised zeolites for the selective reduction of biomass derived carboxylic acids to alcohols

Octanoic acid (OA) was used as reactant with medium chain length to model the aliphatic carboxylic acids which can be produced by catalytic, thermochemical or biological degradation of biomass. A flow through reactor was applied at 21 bar total pressure (in general at 20 bar hydrogen and 1 bar octanoic acid partial pressures) and 330-380 °C. Cu A-, X- and Y-zeolite based catalysts were pretreated in hydrogen flow at 450 °C. During reduction/dehydration A- and X-zeolite structures collapsed and aluminosilicate supported copper catalysts were formed, which contain copper nanoparticles in high dispersion. The catalyst samples were modified by In2O3 co-catalyst. Fatty acid conversion activity of amorphized zeolite supported Cu catalysts and the yield of selectively produced alcohol can be increased drastically by In2O3 addition. Appearance of metallic indium can effectively rein in the step by step catalytic reduction at alkanol formation previous to dehydration of alcohols to alkenes and ethers

Primary meningioma of the middle ear: case report

Abstract Objective: To report a rare case of primary meningioma of the middle ear. Method: We describe the case of a 55-year-old woman who presented with decreased hearing and fullness in the left ear, with a middle-ear mass. We also review the world literature regarding primary extracranial meningioma of the middle ear and its management. Results: Primary middle-ear meningioma, a rare clinical entity, was diagnosed in this patient based on an initial transmastoid biopsy. Magnetic resonance imaging with gadolinium enhancement excluded the presence of an intracranial component. Complete excision of the tumour was achieved using a combined approach tympanoplasty. The patient had an uneventful post-operative course. Conclusion: Meningiomas, although rare in the middle ear, need to be included in the differential diagnosis of middle-ear lesions presenting to the otolaryngologist. This case emphasises the management strategy required when dealing with a middle-ear mas

Optical emission spectra analysis of thermal plasma treatment of poly(vinyl chloride)

Abstract Decomposition of poly(vinyl chloride) (PVC) was investigated in radiofrequency thermal plasma in neutral, oxidative and reductive conditions. Optical emission spectroscopy (OES) was applied for the characterization of the plasma column. OES was used to identify active plasma components such as excited atoms, ions, radicals and molecules. The spectra were dominated by molecular C2, CN, OH, and CH bands, and atomic H, Ar, C, Cl and O lines. Emission intensities of main species were monitored versus various experimental parameters. The rotational-vibrational temperatures determined from different bimolecular species were considered in the range of 2000–6400 K. Solid soot samples were collected and purified to investigate the possibility of graphene formation as a by-product of the decomposition process.</jats:p

Dermatofibroma: a curious tumor.

A tumor, such as a dermatofibroma, causes consternation among many patients, but it rarely creates problems on its own. Also called a histiocytoma, it remains one of the most common mesenchymal growths. Its etiology is unknown with the previous theory that it is a dermal response to injury, such as an insect bite, being challenged. As much as patients like to blame spiders or other arthropods for traumatizing an arm or leg, no definitive explanation is available for its etiology

Report on the survey for Bursaphelenchus xylophilus and the occurrence of other Bursaphelenchus species in Hungarian coniferous forests.

An ongoing official survey to detect the pine wood nematode Bursaphelenchus xylophilus, a quarantine pest, started in 2003 in coniferous forests in Hungary. Based on the results of the study from 2003–11, B. xylophilus has not yet been detected in Hungary. Two other Bursaphelenchus species (B. mucronatus and B. vallesianus) were identified in samples in 2009. Details of the survey and the measurements of B. mucronatus and B. vallesianus are provided