Power flows and efficiency analysis of out- and input coupled IVT

Since late 1995, when the high-powered (194 kW) Fendt Favorit 926 equipped with a ´´Vario´´ transmission was launched, power machines with CVT (Continuously Variable Transmission) have appeared on the palette of all major tractor manufacturing companies as well. The CVT unit in the transmission of these power machines is not included directly in the power flow, but in one of the power branches after a split. By modifying the gear ratio of a properly selected CVT unit, the transmission can be geared neutral and the direction of progress of the vehicle can be changed. The transmission structure produced so is called power split IVT (Infinitely Variable Transmission). The paper presents the ways of producing an IVT drive and analyzes the Fendt ``Vario´´ driving mechanism with OC-RSC structure and the same elements but with IC-RSC structure. There is detailed analysis on both structures on power flows (power split, positive/negative power circulating), the Geared Neutral and the backward operational stages, taking into account the significant states from efficiency calculation point of view, together with changes thereof in function of output revolution. Based on these investigations it is highlighted that the entire range of the course of the vehicle can be covered by an output coupled system adjusting the gear of the CVT unit within the high-efficiency range. The task is the same for input coupled systems, to be realized by planetary gears installed after the IVT unit and by the proper control of their engagement

Húgyúti kórokozó Escherichia coli virulenciájára irányuló vizsgálatok = Investigations on the virulence of uropathogenic Escherichia coli

Az Escherichia coli fő húgyúti virulencia faktorainak vizsgálatával bizonyítottuk, hogy az alfa hemolizin a toxicitásért felelős legjelentősebb pathogenetikai tényező, emellet a tok és fimbriák a kolonizációban jászanak fontos szerepet. A haemolysin operont tartalmazó pathogenitási szigetet in vitro és egerek bélscatornájában in vivo is át tudtuk vinni a genus más képviselőjébe. Emellett a hemolizin operon kicserélhetőségét bizonyítottuk Escherichia és Proteus törzsek között szintén in vivo környezetben is. A hemolizáló rekombinánsok virulenciája a recipienshez képest szignfikánsan magasabb. Hibridizációs kísérletekkel az E. coli és Proteus penneri haemolizin operonjainak homológiáját bizonyítottuk. Gyakorlati jelentőségű megfigyelés, hogy a rezisztens hemolizáló törzs antibiotikum kezelés esetén a bélcsatornában elszaporodva életet veszélyeztető fertőzés forrása lehet. A hemolzin és fimbria operonok szabályozásában jelenős mechanizmusokat tártunk fel. | In mouse experiments we have proved that alpha-haemolysin with its toxic effect is the main urinary virulence factor of E. coli. Besides fimbrial adhesins and the capsule are important in the first colonisation step of the infection. The pathogenicity island containing the haemolysin operon could be transferred from the wild type strain to non-hemolytic E. coli strains in the mouse intestine. Furthermore, the haemolysin operon is exchangable in vivo between E. coli and Proteus strains. The haemolytic recombinants present with significantly increased virulence in various mouse models. With hybridisation experiments we could prove homology between the haemolysin operons of E. coli and Proteus penneri. The observation that antibiotic resistant haemlysin producing E. coli in the microbiota may elicit severe infection in the antibiotic treated patients may be of paractical significance. Regulatory machineries governing the expression of haemolysin and fimbria operons were also elucidated

Numerical simulation of soil–cone penetrometer interaction using discrete element method

One of the most common methods to measure soil strength in-situ is cone penetrometers. In this paper the development of a three dimensional (3D) discrete element model (DEM) for the simulation of the soil–cone penetrometer interaction in a slightly cohesive loamy sand soil is presented. The aim was to investigate the effects of the soil model’s geometrical (e.g., soil model cross section shape and size and model’s height) changes on variations in the soil penetration resistance. The model area ratio and height ratio values were adopted to analyse the effects of the cross section size and the model’s height, respectively. The results of penetration resistance of the DEM simulations were compared with the in-situ measurement with a cone penetrometer of the same geometry. This comparison allowed the derivation of the contact properties between the elements. To simulate the soil material the so-called Parallel Bond and Linear Models were used in the 3D version of the Particle Flow Code (PFC) software. Finally the mechanical properties of the soil, namely the cohesion and internal friction angle were estimated by DEM simulation of direct shear box. Results showed that the penetration process can be simulated very well using the DEM. The model’s calculated penetration resistance and the corresponding in-situ measurement were in good agreement, with mean error of 14.74%. The best performing models were a rectangular model with an area ratio of 72 and a height ratio of 1.33 and a circular model with an area ratio of 32 and a height ratio of 2. The simulation output of soil material properties with direct shear box resulted in representative values of real loamy sand soils, with cohesion values range of 6.61–8.66 kPa and internal friction angle values range of 41.34–41.60°. It can be concluded that the DEM can be successfully used to simulate the interaction between soil and cone penetrometers in agricultural soils

Ötödfélszáz énekek, Pálóczi Horváth Ádám dalgyűjteménye az 1813. évből

Sajtó alá rendezte Bartha Dénes és Kiss József, Akadémiai Kiadó 195

Pontszerű szennyező források tájra gyakorolt hatásának vizsgálata = Examinations on the effects on landscapes of point-sources of pollution

A talajszennyező forrásokat Mikepércs és Újszentmargita települési folyékonyhulladék-leürítője esetében vizsgáltuk. E szennyező források körül béléscsövezett furatokat létesítettünk. A talaj- és vízminták alapján megállapítottuk, hogy bár vannak eltérések, általában hasonló szennyezési tendenciák tapasztalhatók. Mindkét helyszínen jelentős ammónium- és nitrát-szennyezést mutattunk ki, a legjobb szennyezés-terjedési indikátornak pedig, a Na+ bizonyult. A szennyezés néhány száz méteres távolságig volt kimutatható. A pontszerű légszennyező források közül a pálházai perlitbánya szennyező hatását vizsgáltuk. Megállapítottuk, hogy csak a bánya néhány száz méteres körzetén belül kell jelentősebb porterheléssel számolnunk. Ebben a zónában előfordultak az egészségügyi határértéket meghaladó ülepedő pormennyiségek, a bányától 1 km-nél távolabb viszont már nem tapasztaltunk határérték túllépést, igaz, a szennyező hatás még 2-3 km távolságban is egyértelműen kimutatható volt. Megállapítást nyert, hogy a meteorológiai viszonyok jelentősen befolyásolják a porszennyezés alakulását. | We examined the soil-pollutant sources in the case of the communal sewage deposition sites in Mikepércs and Újszentmargita. Around these sources we established boreholes with drill-pipes. According to the water and soil samples we stated that although there are differences, in general, similar tendencies can be discovered. We detected significant ammonium and nitrate pollution in both sites, and we found out that the best indicator for the spreading of the pollution is the Na+. The pollution could be evinced in a few hundred meters from the sources. Of the point-sources of the air-pollution we examined the effects of the perlite-mine in Pálháza. We found that there is more remarkable dust-load only in a few hundred meter zone around the mine. In this zone the amount of the settling dust exceeded the hygienic limit, farther than 1 km from the mine there were not higher value than the hygenic limit, but it is true that the pollutant effect could be unambiguously pointed at 2-3 km distance as well. It was proved that the weather condition notably influences the dust pollution

Dichloridobis(2-methoxy­dibenzo[c,e][1,2]oxaphospho­rine-κP)platinum(II) trichloro­methane solvate

The title compound, [PtCl2(C13H11O2P)2]·CHCl3, has a rare PtCl2 bridging of two dibenzooxaphospho­rine ligands through the metal atom. The PtII ion is in a slightly distorted square-planar environment. The trichloro­methane solvent mol­ecule shows rotational disorder (major occupancy is 0.75) and is placed near to the inversion centre at (1/2, 1/2, 0) in channels parallel to the a axis. The solvent mol­ecule is linked to the complex mol­ecule via inter­molecular bifurcated C—H⋯Cl and C—H⋯O hydrogen bonds. The crystal structure is further stabilized by π–π inter­actions involving the benzene rings, with a centroid–centroid distance of 3.658 (8) Å