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Synthesis, characterization, and enhanced optical and dielectric properties of pure and Ni-doped ZnO nanoparticles for advanced electronic applications /
No full textstructural, optical, and electronic properties, making them ideal candidates for various advanced applications. This study focuses on the synthesis, characterization, and evaluation of the electrical and electronic properties of pure and Ni-doped ZnO nanoparticles (Ni:ZnO) synthesized via a co-precipitation method with varying Ni concentrations (2%, 4%, 6%, and 8%). X-ray diffraction analysis confirmed the wurtzite hexagonal structure of ZnO, with lattice distortion increasing proportionally to Ni doping. A secondary NiO phase was detected at higher doping levels, indicating the solubility limit of Ni in ZnO. The average crystallite size, calculated using Debye-Scherrer’s equation, decreased from 31 nm in pure ZnO to 23 nm in 8% Ni-doped ZnO, confirming dopinginduced size reduction. UV-visible spectroscopy revealed a blue shift in the optical bandgap from 3.23 eV for pure ZnO to 3.41 eV for 8% Ni-doped ZnO, attributed to Burstein-Moss effect. Fourier transform infrared spectroscopy identified changes in vibrational modes, with shifts in peaks corresponding to Zn-O and Ni-O bonds, indicating successful Ni incorporation. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy confirmed uniform particle morphology and elemental composition. Dielectric studies showed that the dielectric constant increased significantly with Ni doping, reaching a maximum value of 69 at 6% doping, while AC conductivity improved with frequency, demonstrating frequency-dependent conductivity due to hopping charge carriers. The findings reveal that Ni doping enhances the structural, optical, and dielectric properties of ZnO, making it suitable for optoelectronics, high-frequency devices, and dielectric materials
Factors influencing the carbonation kinetics of calcium silicate-based binders – an overview /
No full textThe production of hydraulic binders, representing the essential constituent part of concrete and mortar, can be associated with high energy consumption and huge CO2 emissions (at least 2.4 billion tons in 2022). Without appropriate measures, the situation will only worsen. The global annual output of cement stood at 4.4 billion tons of cement, whereas the annual production has been increasing at a rate of ca 5%. In order to significantly reduce CO2 emissions, the following solutions are most widely used in the world: clinker additives; unconventional fuels; decreased energy-related expenses; and technological innovations. However, these are not sufficient to cut down on greenhouse gas emissions and bring them close to zero. Therefore, the utilization and development of alternative binders denoted by a reduced CO2 footprint in comparison to that of conventional cement are among the main objectives of building materials manufacturers as well as researchers. This paper reviews obstacles, solutions and alternatives for the fabrication of hydraulic cementitious materials, along with the general principles of the carbonization of binders, such as natural processes and intensified processes, the impact of various parameters on the chemical and physical transformations, as well as the mechanism of interaction of OPC, belite, and blended cement with CO2. The production of low-lime binders, along with time-optimized carbonation, can significantly improve carbon footprint values. However, due to the huge variety of blended cements, their hardening process by mineral carbonation needs to be investigated extensively and systematically, as it is emphatically dependent on many numerical values and criteria. Environmentally and economically acceptable production can only be achieved on the grounds of the optimized parameters of the entire process
Job crafting influence on employee work engagement.
No full textThis master's thesis examines the influence of job crafting on employee work engagement, particularly in different work environments – traditional, remote, and virtual reality spaces. The objective of the research is to reveal how job crafting affects employee work engagement and which factors contribute to this impact in various work settings. The thesis identifies aspects of job crafting related to employees’ tasks, relationships, and work perception, and explores how these elements can be applied to increase employee motivation and effectiveness. The subject of the research is job crafting and its impact on employee engagement, considering different work environments. First, the concept and dimensions of employee work engagement are explored based on Schaufeli and Bakker’s model (2004), and the principles of job crafting and its application in various work environments are discussed, drawing from theoretical sources and empirical studies. The paper examines how job crafting in traditional, remote, and VR work environments fosters employee engagement and what strategies can be applied to address the unique challenges of these settings. The research methodology includes both a theoretical literature review and an empirical study, which was conducted using semi-structured interviews with employees and managers. The empirical results revealed that job crafting has a positive impact on employee engagement, particularly in remote and VR work environments, where employees often face challenges related to social isolation and work motivation. The VR environment, as an innovative work model, provides employees with the opportunity to actively shape their work environment, which can enhance their engagement and motivation. The findings of the thesis indicate that job crafting initiatives are important not only in traditional work environments but also in remote and virtual spaces. To ensure high levels of employee engagement, organizations are recommended to implement job crafting programs that help employees adapt their work to their personal needs and values. It is also crucial to consider the specific characteristics of each work environment and apply appropriate job crafting strategies to enhance employee motivation and improve organizational performance
Study of fundraising of non-governmental organizations through crowdfunding platforms.
No full textCrowdfunding platforms are increasingly becoming an important alternative to traditional funding methods for non-governmental organizations (NGOs). The development of digital technologies has enabled organizations to reach a broader audience more easily, but it has also introduced new challenges related to transparency, accountability, and donor trust. With the growing competition for funding and rising donor expectations, it has become essential for NGOs to seek innovative solutions that ensure effective fundraising and enhance their public reputation. Therefore, it is crucial to examine the factors that influence successful fundraising through crowdfunding platforms. The aim of the study is to investigate the factors that drive the success of non-governmental organizations in attracting funding through crowdfunding platforms. The theoretical part of the research discusses the core principles of NGO activities, the diversity of funding sources, crowdfunding models and platform types, as well as the importance of accountability in building trust. In the empirical part, an online survey conducted among Lithuanian NGOs revealed their experiences, motivational factors, challenges encountered, and specific aspects of crowdfunding platform utilization. The collected data were analyzed using descriptive statistics and qualitative analysis of open-ended responses. The research results showed that organizations that actively communicate with donors have greater opportunities to attract funding through crowdfunding platforms. A high level of transparency and regular dissemination of activity results are also essential. In addition, clear and emotionally engaging information about the organization’s activities enhances donor engagement and trust. Diversified funding sources, a professional organizational image, and accountability significantly contribute to building donor confidence. The recommendations presented in the study may be useful for representatives of the NGO sector who seek to more effectively use the potential of crowdfunding platforms, increase the visibility of their activities, and expand their funding base
Interaction between performance measurement and internal control systems in health care institutions.
No full textHealth care facilities play an important role in society, but their activities often face challenges of transparency, accountability and effective governance. Although the sector has various approaches to performance measurement and internal control, these are often lacking in practice coherence and systematic and consistent application. This thesis has sought to explore this further; how performance measurement and internal control systems interact and how they influence each other, the quality of an institution‘s performance and decision-making. The object of the study was one of the Lithuanian primary health care institutions representing public sector, whose activities are based on social value creation rather than profit making for the population. The aim of the study is to provide a comprehensive analysis of the performance measurement and internal theoretical and practical aspects of the interaction between the assessment of internal control and the evaluation of internal control, to develop a conceptual model of their integration and empirically justify its implications for the efficiency of health facility management and service to improve the quality of healthcare services. Objectives of the study: 1. to reveal the relevance of organizational performance measurement and the role of internal control, to highlight the interrelationship between them; 2. to analyze the principles of performance appraisal and internal control in healthcare institutions and to develop a conceptual framework for the evaluation of performance of health care institutions and internal a conceptual model of the interaction between health care organizations and internal control systems; 3. to develop a framework for the interaction between performance assessment and internal control systems in health care institutions a methodology for examining the interaction between internal control and internal control systems; 4. to assess the performance of the PSPC in terms of financial, user, process and staff learning and to assess the performance of the following indicators in terms of performance indicators from a health, consumer and consumer/professional perspective, including internal control aspects, and to provide proposals for a more effective, continuous improvement-oriented approach to PSPC performance assessing the performance of the PSPC
Deconstructing sustainability challenges in the transition to a four-day workweek: the case of private companies in Eastern Europe /
No full textAs global challenges escalate—economic shocks, environmental issues, and evolving work expectations—the four-day workweek (4DWW) is gaining traction as a sustainable and viable alternative. This study investigates the transition from a traditional 5-day workweek to a 4DWW in the context of private companies in the Baltic States, supplemented by the insights from informal interviews with 17 representatives across Latvia, Lithuania, and Estonia and an in-depth case study of a Latvian wholesale company. Employing a mixed-methods approach, the research integrates document analysis, structured interviews, and quantitative assessment of key performance indicators over an 8-year period. The findings elucidate the phased transition process, detailing the multifaceted challenges encountered at individual, operational, and strategic levels. The study evaluates the impact of the 4DWW on organizational productivity, employee well-being, and environmental outcomes. Results indicate that, while the 4DWW can sustain or enhance operational efficiency and substantially improve work-life balance and stress reduction, these benefits are not uniformly observed across all economic sectors. This paper not only advances the literature on workweek restructuring by clarifying the algorithm for transitioning to a 4DWW but also underscores its potential as a sustainable business practice. The results offer valuable decision-making insights for private companies considering similar transitions, while also highlighting the need for context-specific strategies and policy support—including relevant legislative frameworks in the Baltic region—to ensure successful implementation
Ultra-high dose rate electron beam dosimetry using Ag nanoparticle-enhanced nPAG and NIBMAGAT gels /
No full textFLASH radiation therapy is an emerging technique that provides several advantages over conventional radiotherapy. By delivering ultra-high dose rate radiation, the damage to healthy tissues surrounding the treatment area is minimized, treatment time is reduced and treatment outcomes of radioresistant tumors are improved. Despite its promising potential, FLASH radiation therapy remains relatively understudied, particularly in the field of dosimetry. Polymer gel dosimetry is a promising technique for verifying FLASH radiation therapy because it enables volumetric dose distribution measurements with high spatial accuracy. This study investigates the applicability of two commonly used polymer gel dosimeters, nPAG and NIBMAGAT, enhanced with nanoparticles, in ultra-high dose rate radiation therapy. The results indicate that NIBMAGAT gel, enriched with Ag nanoparticles, outperforms nPAG. NIBMAGAT gel exhibits less saturation at high doses, maintains dose rate independence and offers comparable sensitivity to nPAG formulation
Modification by fluorine as efficient tool for the enhancement of the performance of organic electroactive compounds – a review /
No full textFunctionalization of organic semiconductors with fluorine atoms and fluorine-containing groups can give rise to a wide variety of properties, for example, increase the rate of electron transport, induce harvesting of non-emissive triplet excitons through thermally activated delayed fluorescence (TADF) or room temperature phosphorescence (RTP), improve photoluminescence quantum yield (PLQY) by forming multiple intra-and intermolecular interactions, and increase solution-processabitily of the compounds, therefore, lowering the cost of device fabrication. Diverse synthetic approaches have been implemented to afford fluorinated organic semiconductors. In this review, we discuss some of the recent and most interesting organic semiconductors with C–F and C–CF3 bonds as well as their application