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This paper presents an analysis of the costs, failure rate, vulnerability, and safety of electric, hybrid, and internal combustion vehicles (EV, HEV, and ICEV), including a review of literature sources, calculations, and investigations. Many literature sources do not provide information on maintenance costs (including repairs and servicing) and limit themselves to energy costs only. However, this cost is not the total cost of the maintenance of a vehicle. There is a lack of analysis of the difference between the maintenance and operating costs of vehicles. Similarly, vulnerability is difficult to determine in vehicles that are used for a short time in the market. The article presents an analysis of literature sources and industry reports on electromobility on maintenance costs, determines the failure rate, calculates vulnerability indices based on a survey, and carries out an expert risk assessment using the FMEA method. In the surveyed companies, the largest percentage of repairs are maintenance and service, mechanical, electrical and electronic, bodywork, and other repairs for each vehicle. Some of the most common faults in electric and hybrid vehicles are battery failures. The only hazard with a tolerable impact is the lack of sufficient data in the maintenance analysis. This risk can be mitigated in subsequent stages of product readiness once more data have been analysed. [ABSTRACT FROM AUTHOR]

The equipment of airport security screening checkpoints undergoes frequent modifications due to technological or organizational changes. New solutions complement or replace existing ones to improve the effectiveness of the equipment or formal requirements. An example of this process is the replacement of the walk-through metal detection gate with a newer solution: the body scanner. The present study aimed to analyze the capacity of an airport security checkpoint under different operational conditions, depending on the equipment used. For this purpose, a previously created model (implemented as a colored, timed, stochastic Petri net) was used. Simulation studies were performed in four real-world operational scenarios, and their results were compared to those of a nominal scenario. The results show that, in terms of capacity, it may be advantageous to redirect a more significant stream of passengers to a station equipped with a specific device, depending on the specific operational situation. The results demonstrate the necessity of analyzing the applied strategy of operation with each change in the operational environment. In particular, for an airport with characteristics similar to Katowice Airport, using older technology is beneficial under nominal conditions and after increasing the staffing so that both genders work simultaneously. In other cases, the more intensive use of Body Scanner-equipped security screening checkpoints is advantageous. [ABSTRACT FROM AUTHOR]

The development of airport security screening systems requires the use of increasingly sophisticated and effective equipment to detect prohibited or hazardous items and substances. However, this can lead to a reduction in the throughput of the security checkpoint (SCP). This paper addresses the operationally important problem of the dilemma between screening effectiveness and screening checkpoint throughput, which is important to the real operational capabilities of an airport. In this paper, a comparison of traditional walk-through metal detectors (WTMD) gates and newer technology body scanners (BSs) was carried out in terms of SCP throughput as an element determining the operational capabilities of the airport. For this purpose, a simulation model was developed to study throughput based on a colored timed Petri net. The analysis showed that, depending on the characteristics of the available staff, the level of terrorist and epidemic threat, as well as the time of year, it is advantageous to use different strategies to vary the size of the stream of passengers directed for screening by the WTMD gate and BS. [ABSTRACT FROM AUTHOR]

Due to their unique molecular architecture translating into numerous every-day applications, carbon nanotubes (CNTs) will be ultimately an increasingly significant environmental contaminant. This work reviews qualitative/quantitative analyses of interactions of various types of CNTs and their chemically modified analogues with aqueous/aquatic media containing organic and inorganic contaminants and selected organisms of aquatic ecosystems. A special emphasis was placed on physicochemical interactions between CNTs as adsorbents of heavy metal cations and aromatic compounds (dyes) with its environmental consequences. The studies revealed CNTs as more powerful adsorbents of aromatic compounds (an order of magnitude higher adsorption capacity) than metal cations. Depending on the presence of natural organic matter (NOM) and/or co-contaminants, CNTs may act as Trojan horse while passing through biological membranes (in the absence of NOM coordinating metal ions). Nanotubes, depending on flow conditions and their morphology/surface chemistry, may travel with natural waters or sediment with immobilized PAHs or metals and/or increase cyto- and ecotoxicity of PAHs/metal ions by their release via competitive complexation, or cause synergic ecotoxicity while adsorbing nutrients. Additionally, toxicity of CNTs against exemplary aquatic microorganisms was reviewed. It was found for Daphnia magna that longer exposures to CNTs led to higher ecotoxicity with a prolonged CNTs excretion. SWCNTs were more toxic than MWCNTs, while hydrophilization of CNTs via oxidation or anchoring thereto polar/positively charged polymer chains enhanced stability of nanotubes dispersion in aqueous media. On the other hand, bioavailability of functionalized CNTs was improved leading to more complex both mechanisms of uptake and cytotoxic effects. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the adsorption capacity of the smectite clays (from the overburden of the lignite deposit in Belchatow) for two anionic dyes, i.e. Reactive Blue 81 (RB-81) and Direct Blue 74 (DB-74). Additionally, the influence of the thermal and chemical (acid and alkali) clay modifications on the amount of bonded dyes was investigated. The adsorption capacity of the clay (natural and modified) was different for studied dyes and depended on the initial concentration and modification type. All the modified clays adsorbed the dyes at pH>pHPZC as the negatively charged surfaces of their particles (in accordance with the formula: AOH ↔ AO- + H+) prevented the formation of electrostatic bonds between the anionic dyes and the clay surface. The dyes were mainly bound with the hydrogen bonds forming between the donor groups in the dyes and the acceptor groups (-SiO and -Al2OH) in the clays. The coefficients in the adsorption isotherms were estimated with the linear and non-linear regression. The linear regression method was found that the Freundlich and Dubinin-Radushkevich isotherms described the dye sorption much better than the Langmuir model. On the other hand, all three models described well the experimental data in the non-linear regression method. Furthermore, the 1/n value (<1) obtained from the Freundlich equation for all the dye-sorbent systems indicated the favorable sorption. [ABSTRACT FROM AUTHOR]

Sorption capacities of low-moor peats and Neogene clays from the overburden of lignite beds in Central Poland for Cr(III) ions as chloride and metalorganic complex ions have been investigated. The binding mechanisms and sorption parameters were determined based on the Freundlich and Langmuir nonlinear sorption isotherms. The sorption capacities of studied materials for Cr(III) ions depended on their properties (porosity, average pore diameters, specific surface area and content of Fe hydroxyoxides) as well as charge of Cr(III) ions, functional groups and their diagonal lengths. Cr(III) ions from chlorides were bound onto sorbents via Coulomb attraction and by Fe hydroxyoxides. However the complex Cr(III) ions were bound to the sorbent surface via hydrogen bonds between the dye -OH groups and =O of the sorbent functional groups. The equation parameters of sorption isotherms indicate cooperative heterogeneous adsorption at low Cr(III) concentrations and chemisorption at high Cr(III) concentrations. [ABSTRACT FROM AUTHOR]