Search Results (6)

The present work provides new evidence of the ongoing potential of surface-active ionic liquids (SAILs) and surface-active quaternary ammonium salts (surface-active QASs). To achieve this, a series of compounds were synthesized with a yield of ≥85%, and their thermal analyses were studied. Additionally, antimicrobial activity against both human pathogenic and soil microorganisms was investigated. Subsequently, their surface properties were explored with the aim of utilizing SAILs and surface-active QASs as alternatives to commercial amphiphilic compounds. Finally, we analyzed the wettability of the leaves’ surface of plants occurring in agricultural fields at different temperatures (from 5 to 25 °C) and the model plant membrane of leaves. Our results show that the synthesized compounds exhibit higher activity than their commercial analogues such as, i.e., didecyldimethylammonium chloride (DDAC) and dodecyltrimethylammonium bromide (C₁₂TAB), for which the CMC values are 2 mM and 15 mM. The effectiveness of the antimicrobial properties of synthesized compounds relies on their hydrophobic nature accompanied by a cut-off effect. Moreover, the best wettability of the leaves’ surface was observed at 25 °C. Our research has yielded valuable insights into the potential effectiveness of SAILs and surface-active QASs as versatile compounds, offering a promising alternative to established antimicrobials and crop protection agents, all the while preserving substantial surface activity. Full article

Carbon fiber reinforced polymer (CFRP) composites are increasingly being used to strengthen structures and to retrofit existing structures. CFRP composites are used in various industries: construction, automotive, and many others. This literature review has shown that CFRP composites find numerous practical applications. Improving structures by reinforcing them with CFRP composite is an innovative approach in design. This review aims to explore the current state of the art in the types of structures that can be reinforced with CFRP, and modifications to the CFRP composite as an additional aspect to increase the strength of the reinforced structure. It has been shown that regardless of the type of reinforced material, the most critical element in this connection is the bonded joint. Proper surface preparation and the use of an appropriate adhesive are also important. Full article

The aim of this paper is to assess the impact of reforms introduced in the operation of Polish open pension funds on management style, risk exposure and related investment performance. The article analyzes the impact of the reformed regulations on the herd behavior of fund managers. In particular, we examined whether the elimination of the internal benchmark for fund evaluation impacts the elimination or reduction of herd behavior. We proposed a multi-factor market model to evaluate the performance of funds investing in various types of instruments. Moreover, we used panel estimation to directly take into account the impact of the internal benchmark on herd behavior. Our results indicate that highly regulated funds may slightly outperform passive benchmarks and their unregulated competitors. In the case of Polish open pension funds, limiting investments in Treasury debt instruments clearly resulted in increased risk and volatility of returns. However, it also raised competition between funds and decreased the herd behavior. Additionally, the withdrawal of the mechanism evaluating funds based on the internal benchmark was also important in reducing herd behavior. Full article

Reducing emissions of pollutants from transport is clearly one of the main challenges of the constantly developing world. Because the environmental impact of different means of transport is significant, it is necessary to cut down on fossil fuels and turn to more eco-friendly solutions, e.g., electric vehicles. Almost all European countries are now adapting their transport policies to this new paradigm. Nonetheless, due to large economic disparities, these processes are currently at different levels of implementation in Western and Eastern Europe. The main focus is on private electric cars and more traditional means of transport, rather than water trams. This article presents possible means of developing water tram lines in Gdańsk served by hybrid or full-electric vehicles. The analysis presented herein reflects the multidimensional nature of the issue. The article provides data on the socio-economic situation in the city, technical issues related to the implementation of such tram lines, and the possible consequences of introducing a new means of transportation into the existing system. A key part of the analysis is the identification of anticipated economic and environmental consequences of introducing both hybrid and full-electric vehicles into the system. A comprehensive socio-economic and technical-environmental analysis of the possibilities of developing urban electromobility in the form of urban passenger shipping in post-communist countries, such as that presented in this paper, has not been previously published. Full article

Electrically assisted bicycles are anticipated to become an effective tool to limit not only the use of cars in cities but also their negative impact on health, the environment, and passenger transportation in cities. In this paper, we examine the effects of implementing the first fully electric bike (e-bike) sharing system in the Metropolitan Area of Gdańsk–Gdynia–Sopot in Northern Poland, where no other bike sharing system had been introduced before. The aims of this article were to determine the impact of the new e-bike sharing system on the modal choice of citizens, identify barriers to its usage, and find differences between the usage of the system in the core of the metropolitan area and in the suburbs. We used two primary data sets: the survey data collected using the computer-assisted personal interviewing technique (CAPI technique) and the data automatically acquired from the website that monitored the system activities. We performed the analysis by using nonparametric tests and correspondence analysis. We found no evidence suggesting that e-bike sharing can replace large number of private car trips, but we found it likely to be competitive to carsharing, moped, and taxi services. E-bike sharing competes also with public transportation services, but it is also used as the first/last mile of the transportation supplementing public transport system. The major barrier to using this system in central cities of the metropolitan area was the lack of available public bikes, and possession of private bicycles, whereas for residents of the suburbs, the obstacles were the need to transport children, the high price of the bicycle rental/subscription, and the long distance to the docking stations. Full article

The aim of this paper is to evaluate the performance of climate-themed mutual funds, taking into consideration the structure of their asset allocation, especially their geographical focus of investment. Additionally, the influence of differences in the industry allocations on the funds’ investment results is evaluated. Our analyses are based on climate-friendly mutual funds registered in Scandinavian countries (i.e., Denmark, Norway, and Sweden) during 2010–2019. To classify the analyzed funds as climate-friendly, we use the relative carbon footprint measure, which is a novelty in studies on ESG funds (meeting the environmental, social, and corporate governance criteria). In our analyses, we use the absolute performance as well as the relative performance methods. The obtained results confirm that geographical and industrial asset allocations significantly affect the performance of Scandinavian climate-friendly funds. On the basis of our studies, we may state that analyzed mutual funds do not get abnormal returns, and their performance mostly depends on the market state. Additionally, the unconditional firm size factor did not influence the return of particular portfolios, while the conditional firm size factor was significant for European, global, and North American funds. Moreover, the firm value factor was significant. Finally, the momentum factor was only significant for the emerging markets portfolio when it reached positive values. Full article