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The document from the journal "Molecules" issues a correction notice for a study on TiO2-based hybrid systems, clarifying the use of lipopeptides derived from bacterial fermentation instead of the commercial biosurfactant 'Surfactin'. The correction includes changes to the title, text, and figures/tables to accurately reflect the use of lipopeptides in the study, highlighting their diverse properties and potential applications. Detailed results of antibacterial tests on TiO2@LP_S samples obtained through different synthesis methods are provided, along with information on particle size distribution, SAED patterns, and adsorption properties. Revised references focus on the use of lipopeptides as surfactants, and a conflict of interest statement has been added for authors Giovanni Baldi and Valentina Dami. [Extracted from the article]

Smart Cities represent a new paradigm, a new smart and sustainable urban model that is empowered by increasingly sophisticated technologies applied in various sectors of city ecosystem to enable actors to co-create value. The main actors to be engaged in this transformation process are the citizens who in turn can represent multiple actors simultaneously within the urban environment and are actively involved in economic, social and political life. For this reason, this conceptual paper aims to point out the effective smart city patterns enabling factors. This topic can be very issued in small towns where there are numerous structural, cultural and demographical barriers that inhibit their use from every day-life to urban settings of an increasingly digitized Public Administration. After framing cities as smart service systems and given the issues regarding the citizens’ predisposition and ability to use technologies, with effects in terms of value co-creation, smart citizens and capabilities co-elevation have been outlined as drivers. An illustrative case involving a smart tourism app (PayTourist) in a small town in Southern Italy (Castellabate) is proposed to outline the factors that influence the technology acceptance by citizens and the ways to foster a capabilities co-elevation path. It would be appropriate for scholars and practitioners to adopt the service innovation roadmap to design and map the development of smart cities through the capabilities upskilling of actors involved.

Nitrogen-doped titanium dioxide (N–TiO2) is extensively studied in the literature and widely employed as a visible-light photocatalyst. The preparation of this nanomaterial often involves a final calcination step: in this paper, we used microwave technology as an efficient and environmentally friendly tool for the calcination of a mixed anatase/brookite phase precursor containing organic compounds arising from its synthesis. A wide study was performed, comparing results obtained in quartz fiber-made crucibles, porcelain crucibles, microwave (MW) and conventional heating, and also using a pristine TiO2 as a reference material. Weight percentages of the three main TiO2 polymorphs obtained in different calcination conditions were determined by X-ray powder diffraction (XRPD) data and Rietveld refinements, and the results are discussed. We found that the calcination's outcome is dramatically affected by the crucible used: while mixed-phase nanomaterials were obtained when using classic porcelain crucibles, only the rutile phase was obtained when working in a quartz fiber crucible at temperatures as low as 250 °C. The direct material's temperature measurement inside the microwave oven showed that this finding is not due to a microwave effect but to a thermal effect caused by the particular crucible employed that favors better combustion of organics and prompts rutile formation. Nitrogen doping of this material was inferred by ultraviolet–visible–diffuse reflectance spectroscopy (UV–vis–DRS). [ABSTRACT FROM AUTHOR]

In recent years, multifunctional inorganic−organic hybrid materials have been widely investigated in order to determine their potential synergetic, antagonist, or independent effects in terms of reactivity. The aim of this study was to design and characterize a new hybrid material by coupling well-known photocatalytic TiO2 nanoparticles with sodium surfactin (SS), a biosurfactant showing high binding affinity for metal cations as well as the ability to interact with and disrupt microorganisms' cell membranes. We used both chemical and colloidal synthesis methodologies and investigated how different TiO2:SS weight ratios affected colloidal, physicochemical, and functional properties. We discovered a clear breaking point between TiO2 and SS single-component trends and identified different ranges of applicability by considering different functional properties such as photocatalytic, heavy metal sorption capacity, and antibacterial properties. At low SS contents, the photocatalytic properties of TiO2 are preserved (conversion of organic dye = 99% after 40 min), and the hybrid system can be used in advanced oxidation processes, taking advantage of the additional antimicrobial SS properties. At high SS contents, the TiO2 photoactivity is inhibited, and the hybrid can be usefully exploited as a UV blocker in cosmetics, avoiding undesired oxidative effects (UV adsorption in the range between 300–400 nm). Around the breaking point (TiO2:SS 1:1), the hybrid material preserves the high surface area of TiO2 (specific surface area around 180 m2/g) and demonstrates NOx depletion of up to 100% in 80 min, together with improved adhesion of hybrid antibacterial coating. The last design demonstrated the best results for the concurrent removal of inorganic, organic, and biological pollutants in water/soil remediation applications. [ABSTRACT FROM AUTHOR]

Citizens are an essential part of the process of smartification and sustainable development of cities as they must adopt, understand and interact with the enabling technologies of digital transformation of societies, cities, and public administration. Therefore, technology acceptance is crucial to creating smart and citizen-centered cities. This is even more challenging in small towns that suffer from an aging population, desertification, lack of infrastructure, and especially the digital divide. The purpose of this research is to investigate the adoption of an Urban Services Technology (UST) in tourism management within a tourism-oriented small town in Southern Italy. A questionnaire was then constructed according to the 12-variable Urban Service Technology Acceptance Model (USTAM), and 216 responses were obtained from a defined group of 1076 subjects. Analyzing the data with a quantitative approach by conducting Exploratory Factor Analysis (EFA), Confirmatory Factor Analysis (CFA), and Structural Equation Modeling (SEM), the assumptions of the initial model were all rejected and new five factors emerged. The path diagram shows that only the factors Sustainability, Ease and Value have a positive correlation with technology adoption. Future research might investigate the mediating role of socio-demographic variables on technology acceptance by considering geographical and cultural diversity among small towns. [ABSTRACT FROM AUTHOR]

Microwave-assisted synthesis of nanoparticles usually leads to a smaller and more uniformly distributed particle size compared to conventional heating (e.g., oil bath). Numerical simulation can help to obtain a better insight into the process in terms of temperature distribution or to evidence existing different temperature profiles and heating rates between the two techniques. In this paper multi-physics numerical simulation is used to investigate the continuous flow synthesis of titanium oxide nanoparticles starting from alkoxide precursors. Temperature-dependent permittivity of reactants has been measured, including the effects of permanence at the maximum synthesis temperature. A temperature homogeneity index has been defined to compare microwave and conventional heating. Results show that when using microwave heating at 2450 MHz, in the investigated conditions, a much higher temperature homogeneity of the reactants is reached. Moreover, reactants experience different heating rates, depending on their position inside the microwave applicator, while this is almost negligible in the case of conventional heating. [ABSTRACT FROM AUTHOR]