The evolution of the car-making industry

Mass-production, cars, pollution – they all have long become well known and well connected phenomena of the modern life. Nowadays the people can also add to the list such items like awareness, scientific approach, long-term thinking, and environmental responsibility. They are surrounded by a multitude of consumer goods, most of which are produced in a scientific manner, and all of which will more sooner than later end up in the garbage. Cars are the most noticeable – both by size and by numbers – and also the most expensive of all the mass products in people’s view. For many of them they are a clear target for reprimand and regulation, and, as a result, the automotive industry is being increasingly brought under bureaucratic control, together with its whole supplier and distributor network. The author started writing this article in an attempt to place the above process under scrutiny, because it is his firm belief that similar measures, similar tough governmental control will inevitably spill over to other industries, which at the moment are producing more inconspicuous, but still polluting products. The present paper shows the relationship between car-making, supply chain management and the efforts of public administration to protect the environment – a connection with clear practical implications

Long-Range Repulsion Between Spatially Confined van der Waals Dimers

It is an undisputed textbook fact that non-retarded van der Waals (vdW) interactions between isotropic dimers are attractive, regardless of the polarizability of the interacting systems or spatial dimensionality. The universality of vdW attraction is attributed to the dipolar coupling between fluctuating electron charge densities. Here we demonstrate that the long-range interaction between \textit{spatially confined} vdW dimers becomes repulsive when accounting for the full Coulomb interaction between charge fluctuations. Our analytic results are obtained by using the Coulomb potential as a perturbation over dipole-correlated states for two quantum harmonic oscillators embedded in spaces with reduced dimensionality, however the long-range repulsion is expected to be a general phenomenon for spatially-confined quantum systems. We suggest optical experiments to test our predictions, analyze their relevance in the context of intermolecular interactions in nanoscale environments, and rationalize the recent observation of anomalously strong screening of the lateral vdW interactions between aromatic hydrocarbons adsorbed on metal surfaces.Comment: 2 figure

Personal city mobility in the context of sustainable development = Személyes városi mobilitás a fenntartható fejlődés kontextusában

The mass production of the automobiles, as presented in my dissertation, has made private passenger cars so affordable, that we have reached a point, where most people in the developed countries (and not only there) cannot imagine a day without driving. The number of passenger cars continuously increases. The evolution of the automobile, together with the stable growth of living standards lead to our present addiction to vehicles using fossil fuels. This addiction is so serious, that apart from threatening human health through its negative effects, the inefficient use of personal passenger vehicles is wasting colossal resources all over the planet. Although the growth of car ownership in the developed countries is slowing down, that is mostly the result of saturation, not of new thinking. As a whole the wealthier countries continue to increase their already massive car fleets. The outcome of my research (point 4.3) strongly confirmed my hypotheses: • Passenger car buyers and/or users in their choice of personal cars are motivated by convenience, social status, cost efficiency and not by environmentally friendly attitude. • When choosing the means of travel in the city, citizens are mostly motivated by convenience. • However strong the environmental commitment of the citizens is, in itself it will never be enough in terms of personal city mobility, because their desire for safety and comfort is stronger. • Consequently, the sustainable mobility modes based on minimal private car use cannot be expected to spread spontaneously without the strong limitation of the current conventional mobility based on private car use. • All respondents of my research saw personal driving as the best option for city mobility. Some openly oppose car-free days and dislike parking fees (I called this group Speeding Drivers), some admit to prefer big and expensive cars and consider public transport inferior (the group of Comfort Lovers), others verbally support public transport, but prefer not to use it (the group of Environmentally Conscious); or readily agree to possible future congestion fees due to the expectations that it will reduce traffic volumes and only they themselves will keep driving (the group of Rich & Prudent). Additionally my research revealed that even if a group of people fully agrees with the importance of some measures, it will not make them automatically accept these measures for themselves. Like the importance of speed limitation for safety, with which all people will easily agree, but not all of them will accept the strict GPS based speed control. So even if citizens would generally agree that something should be done to make city mobility sustainable, they might probably choose the least inconvenient path for themselves. The time is ripe to offer different patterns. It is time to change the old "dream image" of car ownership, to replace the false prestige of the urban driver with the modern image of the free urban movement backed by affordable, safe, professional and accurate public transport working like precision mechanism around the clock. Based on my research I can voice the opinion that modern municipalities can make cities better places to live by consistently reducing personal driving and constantly enhancing public transport and the green modes of personal transportation

Quantum Tunneling of Thermal Protons Through Pristine Graphene

Atomically thin two-dimensional materials such as graphene and hexagonal boron nitride have recently been found to exhibit appreciable permeability to thermal protons, making these materials emerging candidates for separation technologies [S. Hu et al., Nature 516, 227 (2014); M. Lozada-Hidalgo et al., Science 351, 68 (2016).]. These remarkable findings remain unexplained by density-functional electronic structure calculations, which instead yield barriers that exceed by 1.0 eV those found in experiments. Here we resolve this puzzle by demonstrating that the proton transfer through pristine graphene is driven by quantum nuclear effects, which substantially reduce the transport barrier by up to 1.4 eV compared to the results of classical molecular dynamics (MD). Our Feynman-Kac path-integral MD simulations unambiguously reveal the quantum tunneling mechanism of strongly interacting hydrogen ions through two-dimensional materials. In addition, we predict a strong isotope effect of 1 eV on the transport barrier for graphene in vacuum and at room temperature. These findings not only shed light on the graphene permeability to protons and deuterons, but also offer new insights for controlling the underlying quantum ion transport mechanisms in nanostructured separation membranes

The use of methane as automotive fuel – a step to sustainable economy?

The introduction of CNG (Compressed Natural Gas) as automotive fuel began in Italy as early as in mid- 1930s, and ever since the Italian market has always been highly advanced in this regard. Many other countries followed, some of them quite recently, but nevertheless with impressive results. The appeal of this automotive fuel is based on the fact that compared to gasoline, diesel and LPG (Liquefied Petroleum Gas), CNG is cleaner and cheaper; even more so, this fuel is renewable – it can be produced locally from biogas. Despite its obvious benefits, CNG is barely present in Hungary. This article provides an insight into the topic, highlights obstacles to introduction and suggests appropriate governmental steps. The information is intended to support the activities and the decision-making process of governmental officials, municipalities, car-fleet managers, car dealers and their service departments

Fluctuational Electrodynamics in Atomic and Macroscopic Systems: van der Waals Interactions and Radiative Heat Transfer

We present an approach to describing fluctuational electrodynamic (FED) interactions, particularly van der Waals (vdW) interactions as well as radiative heat transfer (RHT), between material bodies of vastly different length scales, allowing for going between atomistic and continuum treatments of the response of each of these bodies as desired. Any local continuum description of electromagnetic (EM) response is compatible with our approach, while atomistic descriptions in our approach are based on effective electronic and nuclear oscillator degrees of freedom, encapsulating dissipation, short-range electronic correlations, and collective nuclear vibrations (phonons). While our previous works using this approach have focused on presenting novel results, this work focuses on the derivations underlying these methods. First, we show how the distinction between "atomic" and "macroscopic" bodies is ultimately somewhat arbitrary, as formulas for vdW free energies and RHT look very similar regardless of how the distinction is drawn. Next, we demonstrate that the atomistic description of material response in our approach yields EM interaction matrix elements which are expressed in terms of analytical formulas for compact bodies or semianalytical formulas based on Ewald summation for periodic media; we use this to compute vdW interaction free energies as well as RHT powers among small biological molecules in the presence of a metallic plate as well as between parallel graphene sheets in vacuum, showing strong deviations from conventional macroscopic theories due to the confluence of geometry, phonons, and EM retardation effects. Finally, we propose formulas for efficient computation of FED interactions among material bodies in which those that are treated atomistically as well as those treated through continuum methods may have arbitrary shapes, extending previous surface-integral techniques.Comment: 25 pages, 5 figures, 2 appendice

Personal Mobility In The Context Of Sustainable Development

Personal mobility can be shaped by many possible means, from strategic international agreements on joint standards, through national legislation on health and safety, sustainable municipality planning and development, up to education and promotion of environmentally friendly life style. This paper follows some of the main trends in the historical development of the travel demand, and shows the evolution of the personal mobility into an environmentally sensitive area

Photolytic and thermolytic decomposition products from iron pentacarbonyl adsorbed on Y zeolite

Zeolite supported iron systems obtained by photolysis and thermolysis of Fe(CO)5/Na---Y adducts are characterized via evaluation of the respective magnetic isotherms taken with a FONER magnetometer at T = 4.2 K. Thermolysis under fast heating in inert gas and under fluidized shallow bed conditions completes within a few minutes at not, vert, similar 500 K, and gives iron clusters of which at least 70 to 90 wt% is smaller than 1 nm. Prolonged photolysis at 290 K in the same fluidized bed conditions does not result in the formation of ‘naked’ iron(O) clusters, but gives a limited fraction of magnetically coupled Fex(CO)y entities. Photodimerization cannot be excluded to be the main reaction path