
Kaunas University of Technology
UniversityKaunas, Lithuania
Research output, citation impact, and the most-cited recent papers from Kaunas University of Technology (Lithuania). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from Kaunas University of Technology
Tandem solar cells that pair silicon with a metal halide perovskite are a promising option for surpassing the single-cell efficiency limit. We report a monolithic perovskite/silicon tandem with a certified power conversion efficiency of 29.15%. The perovskite absorber, with a bandgap of 1.68 electron volts, remained phase-stable under illumination through a combination of fast hole extraction and minimized nonradiative recombination at the hole-selective interface. These features were made possible by a self-assembled, methyl-substituted carbazole monolayer as the hole-selective layer in the perovskite cell. The accelerated hole extraction was linked to a low ideality factor of 1.26 and single-junction fill factors of up to 84%, while enabling a tandem open-circuit voltage of as high as 1.92 volts. In air, without encapsulation, a tandem retained 95% of its initial efficiency after 300 hours of operation.
We introduce new hole-selective contacts for next-generation perovskite photovoltaics and point to design paths for molecular engineering of perfect interfaces.
The traditional role of food packaging is continuing to evolve in response to changing market needs. Current drivers such as consumer's demand for safer, "healthier," and higher-quality foods, ideally with a long shelf-life; the demand for convenient and transparent packaging, and the preference for more sustainable packaging materials, have led to the development of new packaging technologies, such as active packaging (AP). As defined in the European regulation (EC) No 450/2009, AP systems are designed to "deliberately incorporate components that would release or absorb substances into or from the packaged food or the environment surrounding the food." Active packaging materials are thereby "intended to extend the shelf-life or to maintain or improve the condition of packaged food." Although extensive research on AP technologies is being undertaken, many of these technologies have not yet been implemented successfully in commercial food packaging systems. Broad communication of their benefits in food product applications will facilitate the successful development and market introduction. In this review, an overview of AP technologies, such as antimicrobial, antioxidant or carbon dioxide-releasing systems, and systems absorbing oxygen, moisture or ethylene, is provided, and, in particular, scientific publications illustrating the benefits of such technologies for specific food products are reviewed. Furthermore, the challenges in applying such AP technologies to food systems and the anticipated direction of future developments are discussed. This review will provide food and packaging scientists with a thorough understanding of the benefits of AP technologies when applied to specific foods and hence can assist in accelerating commercial adoption.
The growth in international research on public service motivation (PSM) raises a number of important questions about the degree to which the theory and research developed in one country can contribute to our understanding of PSM in other counties. To help address this issue, this study revisits the conceptual and operational definitions of PSM to address weaknesses previously noted in the literature. Although some important steps have been taken to both improve and internationalize the PSM scale, this work has been done incrementally. In contrast, this study takes a more systematic and comprehensive approach by combining the efforts of international PSM scholars to develop and then test a revised measurement instrument for PSM in 12 countries. Although the resulting four dimensional 16-item measure of PSM reported here provides a better theoretical and empirical foundation for the measurement of PSM, our results suggest that the exact meaning and scaling of PSM dimensions are likely to differ across cultures and languages. These results raise serious concerns regarding the ability to develop a single universal scale of PSM, or making direct comparisons of PSM across countries.
An increasing demand for natural additives has shifted the attention from synthetic to natural antioxidants. The present work examines the potential of some aromatic herbs grown in Lithuania as a source of natural antioxidants: marjoram (Majorana hortensis Moench), catnip (Nepeta cataria L), oregano (Origanum vulgare L), lavender (Lavandula angustifolia Mill), thyme (Thymus vulgaris L), hyssop (Hyssopus officinalis L), anise hyssop (Lophantus anisatus Benth), and sage (Salvia officinalis L). Dried herb samples were submitted to extraction with supercritical CO2, acetone or methanol/water and hydrodistillation. Deodorised herb samples (after removal of essential oil) were also extracted with acetone. The antioxidant activity of these extracts, essential oils and dried deodorised aqueous extracts was assessed by the β-carotene bleaching test (diffusion and spectrophotometric methods). The highest yields of extracts were obtained using polar solvents. Thyme and sage acetone oleoresins showed high antioxidant activity in the tests performed and were regarded as the most promising sources. © 1998 SCI.
Improved stability and efficiency of two-terminal monolithic perovskite-silicon tandem solar cells will require reductions in recombination losses. By combining a triple-halide perovskite (1.68 electron volt bandgap) with a piperazinium iodide interfacial modification, we improved the band alignment, reduced nonradiative recombination losses, and enhanced charge extraction at the electron-selective contact. Solar cells showed open-circuit voltages of up to 1.28 volts in p-i-n single junctions and 2.00 volts in perovskite-silicon tandem solar cells. The tandem cells achieve certified power conversion efficiencies of up to 32.5%.
INTRODUCTION: Gender as a predictor of outcomes of rheumatoid arthritis (RA) has evoked considerable interest over the decades. Historically, there is no consensus whether RA is worse in females or males. Recent reports suggest that females are less likely than males to achieve remission. Therefore, we aimed to study possible associations of gender and disease activity, disease characteristics, and treatments of RA in a large multinational cross-sectional cohort of patients with RA called Quantitative Standard Monitoring of Patients with RA (QUEST-RA). METHODS: The cohort includes clinical and questionnaire data from patients who were seen in usual care, including 6,004 patients at 70 sites in 25 countries as of April 2008. Gender differences were analyzed for American College of Rheumatology Core Data Set measures of disease activity, DAS28 (disease activity score using 28 joint counts), fatigue, the presence of rheumatoid factor, nodules and erosions, and the current use of prednisone, methotrexate, and biologic agents. RESULTS: Women had poorer scores than men in all Core Data Set measures. The mean values for females and males were swollen joint count-28 (SJC28) of 4.5 versus 3.8, tender joint count-28 of 6.9 versus 5.4, erythrocyte sedimentation rate of 30 versus 26, Health Assessment Questionnaire of 1.1 versus 0.8, visual analog scales for physician global estimate of 3.0 versus 2.5, pain of 4.3 versus 3.6, patient global status of 4.2 versus 3.7, DAS28 of 4.3 versus 3.8, and fatigue of 4.6 versus 3.7 (P < 0.001). However, effect sizes were small-medium and smallest (0.13) for SJC28. Among patients who had no or minimal disease activity (0 to 1) on SJC28, women had statistically significantly higher mean values compared with men in all other disease activity measures (P < 0.001) and met DAS28 remission less often than men. Rheumatoid factor was equally prevalent among genders. Men had nodules more often than women. Women had erosions more often than men, but the statistical significance was marginal. Similar proportions of females and males were taking different therapies. CONCLUSIONS: In this large multinational cohort, RA disease activity measures appear to be worse in women than in men. However, most of the gender differences in RA disease activity may originate from the measures of disease activity rather than from RA disease activity itself.
We report on a comparison of methods based on XRD patterns for calculating crystal size. In this case, XRD peaks were extracted from hydroxyapatite obtained from cow, pig, and chicken bones. Hydroxyapatite was synthesized through the thermal treatment of natural bones at 950 °C. XRD patterns were selected by adjustment of X-Pert software for each method and for calculating the size of the crystals. Methods consisted of Scherrer (three models), Monshi-Scherrer, three models of Williamson-Hall (namely the Uniform Deformation Model (UDM), the Uniform Stress Deformation Model (USDM), and the Uniform Deformation Energy Density Model (UDEDM)), Halder-Wanger (H-W), and the Size Strain Plot Method (SSP). These methods have been used and compared together. The sizes of crystallites obtained by the XRD patterns in each method for hydroxyapatite from cow, pig, and chicken were 1371, 457, and 196 nm in the Scherrer method when considering all of the available peaks together (straight line model). A new model (straight line passing the origin) gave 60, 60, and 53 nm, which shows much improvement. The average model gave 56, 58, and 52 nm, for each of the three approaches, respectively, for cow, pig, and chicken. The Monshi-Scherrer method gave 60, 60, and 57 nm. Values of 56, 62, and 65 nm were given by the UDM method. The values calculated by the USDM method were 60, 62, and 62 nm. The values of 62, 62, and 65 nm were given by the UDEDM method for cow, pig, and chicken, respectively. Furthermore, the crystal size value was 4 nm for all samples in the H-W method. Values were also calculated as 43, 62, and 57 nm in the SSP method for cow, pig, and chicken tandemly. According to the comparison of values in each method, the Scherrer method (straight line model) for considering all peaks led to unreasonable values. Nevertheless, other values were in the acceptable range, similar to the reported values in the literature. Experimental analyses, such as specific surface area by gas adsorption (Brunauer-Emmett-Teller (BET)) and Transmission Electron Microscopy (TEM), were utilized. In the final comparison, parameters of accuracy, ease of calculations, having a check point for the researcher, and difference between the obtained values and experimental analysis by BET and TEM were considered. The Monshi-Scherrer method provided ease of calculation and a decrease in errors by applying least squares to the linear plot. There is a check point for this line that the slope must not be far from one. Then, the intercept gives the most accurate crystal size. In this study, the setup of values for BET (56, 52, and 49 nm) was also similar to the Monshi-Scherrer method and the use of it in research studies of nanotechnology is advised.
Linking topology in oligocarbazoles (see figure) has a strong influence on their electronic properties. 3(6),9′-linked oligocarbazoles exhibit unusual suppression of electronic coupling between units, leading to localized excited states and very small reduction of triplet energies (compared to the monomer). Coupled with their excellent morphological stability, this makes them suitable as host materials for blue electrophosphorescence devices. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2089/2007/c0822_s.pdf or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Scholars believe that the newly introduced Industry 5.0 has the potential to move beyond the profit-centered productivity of Industry 4.0 and to promote sustainable development goals such as human-centricity, socio-environmental sustainability, and resilience. However, little has been done to understand how this ill-defined phenomenon may deliver its indented sustainability values despite these speculative promises. To address this knowledge gap, the present study developed a strategy roadmap that explains the mechanism by which Industry 5.0 delivers its intended sustainable development functions. The study first developed and introduced the Industry 5.0 reference model that describes the technical and functional properties of this phenomenon. The study further conducted a content-centric synthesis of the literature and identified the sustainable development functions of Industry 5.0. Next, the interpretive structural modeling (ISM) technique was employed to identify the sequential relationships among the functions and construct the Industry 5.0-enabled model of sustainable development. The ISM involved collecting the opinions of 11 Industry 5.0 experts through expert panel meetings. Results revealed that Industry 5.0 delivers sustainable development values through 16 functions. Circular intelligent products, employee technical assistance, intelligent automation, open sustainable innovation, renewable integration, and supply chain adaptability are examples of the functions identified. These functions are highly interrelated and should be developed in a specific order so that the synergies and complementarities among them would maximize the sustainable development value gains. The roadmap to Industry 5.0-driven sustainability developed in this study is expected to provide a better understanding of ways Industry 5.0 can contribute to sustainable development, explaining how the development of its functions should be managed to maximize their synergies and contribution to the intended sustainability values. The study also highlights important avenues for future research, emphasizing the potential enablers of Industry 5.0 development, such as Government 5.0 or Corporate Governance 5.0.
Abstract The study aims to examine the potential relationship between public health expenditures, logistics performance indices, renewable energy, and ecological sustainability in Association of Southeast Asian Nations member countries. The study used secondary data, which downloaded from the World Bank website and tested for hypotheses using the structural equation modeling. The results show that the use of renewable energy in logistics operations will improve environmental and economic performance to reduce emissions, whereas environmental performance is negatively correlated with public health expenditures, indicating that greater environmental sustainability can improve human health and economic growth. The results also show that increased public health spending and poor environmental performance undermine economic growth in low efficiency and low labor productivity, thus reducing the speed of economic activity. On the other hand, the use of renewable energy in logistics cannot only improve the sustainability of the environment but also create a better national image and provide better export opportunities in environmentally friendly countries to promote sustainable economic growth. The outcomes of this study will help the policy/decision makers to make the proper planning to their investments for achieving sustainable economic growth.
Concomitant with the development of surgical treatment of cardiac arrythmias and management of myocardial ischemia, there is renewed interest in morphology of the intrinsic cardiac nervous system. In this study, we analyze the topography and structure of the human epicardiac neural plexus (ENP) as a system of seven ganglionated subplexuses. The morphology of the ENP was revealed by a histochemical method for acetylcholinesterase in whole hearts of 21 humans and examined by stereoscopic, contact, and bright-field microscopy. According to criteria established to distinguish ganglionated subplexuses, they are epicardiac extensions of mediastinal nerves entering the heart through discrete sites of the heart hilum and proceeding separately into regions of innervation by seven pathways, on the courses of which epicardiac ganglia, as wide ganglionated fields, are plentifully located. It was established that topography of epicardiac subplexuses was consistent from heart to heart. In general, the human right atrium was innervated by two subplexuses, the left atrium by three, the right ventricle by one, and the left ventricle by three subplexuses. The highest density of epicardiac ganglia was identified near the heart hilum, especially on the dorsal and dorsolateral surfaces of the left atrium, where up to 50% of all cardiac ganglia were located. The number of epicardiac ganglia identified for the human hearts in this study ranged from 706 up to 1,560 and was not correlated with age in most heart regions. The human heart contained on average 836 +/- 76 epicardiac ganglia. The structural organization of ganglia and nerves within subplexuses was observed to vary considerably from heart to heart and in relation to age. The number of neurons identified for any epicardiac ganglion was significantly fewer in aged human compared with infants. By estimating the number of neurons within epicardiac ganglia and relating this to the number of ganglia in the human epicardium, it was calculated that approximately 43,000 intrinsic neurons might be present in the ENP in adult hearts and 94,000 neurons in young hearts (fetuses, neonates, and children). In conclusion, this study demonstrates the total ENP in humans using staining for acetylcholinesterase, and provides a morphological framework for an understanding of how intrinsic ganglia and nerves are structurally organized within the human heart.
Abstract The definition of corporate social responsibility (CSR) states that companies must not only pursue their main goal—to maximize profits, but also contribute to the well‐being of society through voluntary efforts. The importance of CSR in today's global world is growing. It is becoming mandatory for companies to engage in socially responsible activities to support the growth of their business. It is argued that companies pursuing CSR initiatives can gain a competitive advantage over other competitors due to creation of a good public image or reputation and generate higher profits and a return on investment however some authors disagree with this. The aim of this article is to analyse the benefits and drawbacks of CSR based on systematic literature review and to develop the conceptual framework for linking CSR with the financial performance of companies. The conducted analysis revealed that in most studies the positive or neutral relationship between CSR and financial results were claimed. Though the negative and alternative connections between these issues are less frequently identified in scientific articles, they cannot be excluded from the analysis and require certain attention and further consideration.
Identification of electronic processes at buried interfaces of charge-selective contacts is crucial for photovoltaic and photocatalysis research. Here, transient surface photovoltage (SPV) is used to study the passivation of different hole-selective carbazole-based SAMs. It is shown that transient SPV and transient photoluminescence provide complementary information on charge transfer kinetics and trapping/de-trapping mechanisms, and that trap-assisted non-radiative recombination losses originate from electron trapping at the SAM-modified ITO/perovskite interface. The hole transfer rates and the density of interface electron traps, obtained by fitting SPV transients with a minimalistic kinetic model, depended strongly on the SAM’s chemical structure, and densities of interface traps as low as 109 cm−2, on par with highly passivated c-Si surfaces, were reached for Me-4PACz, previously used in record perovskite/silicon tandem solar cells. The extracted hole transfer rate constants and interface trap densities correlated well with the corresponding fill factors and open-circuit voltages of high-efficiency solar cells.
Abstract Despite the recent interest in the Industry 4.0 applications for sustainability, little is known on the processes through which digital transformation and Industry 4.0 technologies enable sustainable innovation in manufacturing. The present study addresses this knowledge gap by developing a strategic roadmap that explains how businesses can leverage Industry 4.0 technologies to introduce sustainability into innovative practices. For this purpose, the study conducts a systematic review of extant literature to identify Industry 4.0 functions for sustainable innovation and applies interpretive structural modeling to devise the promised roadmap. The results offer interesting insights into Industry 4.0 applications for sustainable innovation. The strategic roadmap developed reveals that Industry 4.0 enables sustainable innovation through 11 functions. Industry 4.0 and the underlying digital technologies and principles allow businesses to improve interfunctional collaboration and better integrate with internal and external stakeholders. Industry 4.0 further improves the knowledge base and advanced manufacturing competency and promotes organizational capabilities valuable to sustainable innovation such as green absorptive capacity, sustainable partnership, and sustainable innovation orientation. Through these functions, Industry 4.0 subsequently enhances green process innovation capacity and the ability to develop or reintroduce eco‐friendly products economically and competitively. Overall, the roadmap explains the complex precedence relationships among the 11 sustainable innovation functions of Industry 4.0, offering important implications for businesses that seek to leverage Industry 4.0 sustainability implications and manage sustainable development.
Abstract The unprecedented emergence of perovskite‐based solar cells (PSCs) has been accompanied by an intensive search of suitable materials for charge‐selective contacts. For the first time a hole‐transporting self‐assembled monolayer (SAM) as the dopant‐free hole‐selective contact in p–i–n PSCs is used and a power conversion efficiency of up to 17.8% with average fill factor close to 80% and undetectable parasitic absorption is demonstrated. SAM formation is achieved by simply immersing the substrate into a solution of a novel molecule V1036 that binds to the indium tin oxide surface due to its phosphonic anchoring group. The SAM and its modifications are further characterized by Fourier‐transform infrared and vibrational sum‐frequency generation spectroscopy. In addition, photoelectron spectroscopy in air is used for measuring the ionization potential of the studied SAMs. This novel approach is also suitable for achieving a conformal coverage of large‐area and/or textured substrates with minimal material consumption and can potentially be extended to serve as a model system for substrate‐based perovskite nucleation and passivation control. Further gains in efficiency can be expected upon SAM optimization by means of molecular and compositional engineering.
A few decades ago Amaranthus was rediscovered as a most promising plant genus that may provide high-quality protein, unsaturated oil, and various other valuable constituents. Since then research has focused on various Amaranthus spp. and has been rapidly expanding, and a large number of reports have been published. Several review articles focusing on different aspects, such as botanical, agrotechnological, compositional, biological, chemical, and technological properties, as well as applications and health effects, have also been published since then. This comprehensive review is focused on amaranth composition, antioxidant properties, applications, and processing. The composition includes macrocomponets (lipids, proteins, carbohydrates, and dietary fiber) and other important constituents, such as squalene, tocopherols, phenolic compounds, phytates, and vitamins. These aspects of amaranth studies have not been comprehensively reviewed for a long time.
ChatGPT can revolutionize education by enhancing student engagement and making learning more personalized. Drawing on UTAUT2, this study investigated determinants of intention to use ChatGPT for educational purposes. Data were gathered from 406 Malaysian students and analyzed using a hybrid approach including “partial least squares” (PLS) and “fuzzy-set qualitative comparative analysis” (fsQCA). PLS showed that performance expectancy, effort expectancy, hedonic motivation, and learning value significantly influence the intention to use ChatGPT. Furthermore, we found that personal innovativeness and information accuracy negatively moderate the associations between ChatGPT use and its determinants. While PLS demonstrated that social influence, facilitating conditions, and habit do not affect ChatGPT use, fsQCA revealed that all factors might affect the intention to use ChatGPT. fsQCA suggested that eight combinations of factors may lead to high ChatGPT use. The results hold various implications for ChatGPT developers, instructors, and universities and provide insights for accelerating ChatGPT adoption.
In view of the expanding global market, authentication and characterization of botanical and geographic origins of honey has become a more important task than ever. Many studies have been performed with the aim of evaluating the possibilities to characterize honey samples of various origins by using specific chemical marker compounds. These have been identified and quantified for numerous honey samples. This article is aimed at summarizing the studies carried out during the last 2 decades. An attempt is made to find useful chemical markers for unifloral honey, based on the analysis of the compositional data of honey volatile compounds, phenolic acids, flavonoids, carbohydrates, amino acids, and some other constituents. This review demonstrates that currently it is rather difficult to find reliable chemical markers for the discrimination of honey collected from different floral sources because the chemical composition of honey also depends on several other factors, such as geographic origin, collection season, mode of storage, bee species, and even interactions between chemical compounds and enzymes in the honey. Therefore, some publications from the reviewed period have reported different floral markers for honey of the same floral origin. In addition, the results of chemical analyses of honey constituents may also depend on sample preparation and analysis techniques. Consequently, a more reliable characterization of honey requires the determination of more than a single class of compounds, preferably in combination with modern data management of the results, for example, principal component analysis or cluster analysis.
Thermal stability of hybrid solar cells containing spiro-OMeTAD as hole-transporting layer is investigated. It is demonstrated that fully symmetrical spiro-OMeTAD is prone to crystallization, and growth of large crystalline domains in the hole-transporting layer is one of the causes of solar cell degradation at elevated temperatures, as crystallization of the material inside the pores or on the interface affects the contact between the absorber and the hole transport. Suppression of the crystal growth in the hole-transporting layer is demonstrated to be a viable tactic to achieve a significant increase in the solar cell resistance to thermal stress and improve the overall lifetime of the device. Findings described in this publication could be applicable to hybrid solar cell research as a number of well-performing architectures rely heavily upon doped spiro-OMeTAD as hole-transporting material.