Atomic physics, optical technologies, and medical physics.

Tēžu krājums: LU EZTF Atomfizikas un spektroskopijas instītūta organizētās konferences sekcijas 13.-14.februārī / Book of Abstracts: Sessions organised by the Institute of Atomic Physics and Spectroscopy of the FST UL on 13-14 Februar

Effect of rhodium doping for photocatalytic activity of barium titanate

This work was supported by the Ministry of Science and Higher Education of the Republic of Kazakhstan, grant number IRN AP14972859. Institute of Solid State Physics, University of Latvia, as the Center of Excellence, has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.By means of DFT oxygen evolution reaction on Rh-doped BaTiO3 (001) surface has been modeled. Gibbs free energies for each step of the reaction as well as the values of overpotential have been calculated, taking into account the solvation effect. The position of Rh-induces defect energy levels have been determined. Our findings indicated a substantial reduction in overpotential for the Rhodium-modified TiO2 surface compared to the bare surface. The high overpotential on the bare BaTiO3 surface suggests low OER efficiency, making Rh doping a promising strategy for enhancement. © 2024 The Author(s) --//-- This is an open-access article G.A. Kaptagay, B.M. Satanova, A.U. Abuova, M. Konuhova, Zh.Ye. Zakiyeva, U. Zh Tolegen, N.O. Koilyk, F.U. Abuova, Effect of rhodium doping for photocatalytic activity of barium titanate, Optical Materials: X, Volume 25, 2025, 100382, ISSN 2590-1478, https://doi.org/10.1016/j.omx.2024.100382.Ministry of Education and Science of the Republic of Kazakhstan IRN AP14972859; European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

The Legal Justification for Insurers to Deny Insurance Payouts in the Event of an Insurance Claim

Apdrošināšanas jomā bieži nākas saskarties ar apdrošinātāju atteikumiem izmaksāt apdrošināšanas atlīdzību. Darba mērķis ir apkopot un analizēt personu, kurām ir tiesības pretendēt uz apdrošināšanas atlīdzību, tiesības saņemt apdrošināšanas atlīdzību, kā arī apdrošinātāju pienākumus, pieņemot lēmumu par apdrošināšanas atlīdzības atteikumu. Mērķa sasniegšanai darba ietvaros analizētas izmaiņas aktuālajā judikatūrā un normatīvajā regulējumā, aplūkoti trūkumi un pretrunas pastāvošajās tiesībās un pienākumos, kā arī konstatēts problēmjautājums, apdrošinātājiem piemērojot Latvijas Transportlīdzekļu apdrošinātāju biroja metodiskos norādījumus par personu atbildības pakāpes noteikšanu ceļu satiksmes negadījumos.In the field of insurance, it is common to encounter insurers decisions denying paying out insurance compensations for insurance claims. The aim of this thesis is to compile and analyse the rights of individuals entitled to receive insurance compensation and their rights, as well as the obligations of insurers when making decisions to deny insurance claims. To achieve this goal, the author examines changes in current case law and regulatory frameworks, identifies shortcomings and contradictions in existing rights and obligations, and highlights issues arising from insurers' application of the methodological guidelines issued by the Motor Insurers Bureau of Latvia for determining the degree of liability in road traffic accidents

Maģistra darbs

Konkurences tiesību kontekstā, kuras Latvijas likumvides ietvaros likumdevējs centies harmonizēt ar Eiropas Savienības konkurences tiesībām, pastāv nacionālās procesuālās autonomijas princips. Balstoties uz šo principu, katra Eiropas Savienības dalībvalsts patstāvīgi ievieš savus likumus procesuālu jautājumu risināšanai. Zināms, ka paralēli šim principam pastāv arī Eiropas Savienības tiesību virsvadības princips, kas prima facie kolidē ar nacionālās procesuālās autonomijas principu. Tomēr šajā sakarā procesuālo “autonomiju” ierobežo citi principi – efektivitātes princips un ekvivalences princips – , un papildus tam procesuālā autonomija nav piemērojama, kad jau pastāv Eiropas Savienības procesuālie noteikumi. Tomēr no Konkurences padomes prakses izriet uzskatāmas pretrunas nacionālās procesuālās autonomijas pielietošanā. Tādējādi maģistra darba mērķis ir noskaidrot nacionālās procesuālās autonomijas pieļaujamību un identificēt šī principa piemērošanas robežas Konkurences tiesībās.In the context of Competition law, which the Latvian legislator has sought to harmonize with European Union Competition law, the principle of national procedural autonomy is established. Based on this principle, each Member State of the European Union independently introduces its own laws to deal with procedural matters. It is known that this principle is paralleled by the principle of the primacy of European Union law, which prima facie conflicts with the principle of national procedural autonomy. However, in this context, procedural “autonomy” is limited by other principles – the principle of effectiveness and the principle of equivalence – and, additionally, procedural autonomy is not applicable where European Union procedural rules already exist. However, the practice of the national Competition Council shows apparent inconsistencies in the application of national procedural autonomy. The aim of the Master’s thesis is therefore to clarify the admissibility of national procedural autonomy and to identify the limits of the application of this principle in Competition law

Person against whom criminal proceedings have been initiated

Maģistra darbs “Persona, pret kuru uzsākts kriminālprocess” ir veltīts kriminālprocesuālā statusa izpētei un problēmjautājumu analīzei. Latvijas kriminālprocesa sistēmā šis statuss ir pilnīgi jauns un tika ieviests ar Kriminālprocesa likuma stāšanos spēkā. Darba ietvaros tiek vērsta arī uzmanība tiesībām uz aizstāvību, kuras likumdevējam ir bijušas pamatā, lai šādu statusu izveidotu un nodrošinātu šīs tiesības arī personai, pret kuru iegūtie pierādījumi ir ar viszemāko apjomu. Maģistra darba mērķis ir izpētīt kriminālprocesuālā statusa izveidošanu un iekļaušanu Latvijas kriminālprocesa sistēmā, aplūkot statusa jēdzienu un vispārīgu raksturojumu, ietverot personas statusa iegūšanas un izbeigšanās brīža analīzi. Autore izvērtēs arī tiesības un pienākumus, kuri izriet personai iegūstot šo kriminālprocesuālo statusu, kā arī aplūkos ārvalstu regulējumu, lai secinātu vai šāds vai līdzīgs statuss pastāv citu valstu kriminālprocesu likumu reglamentācijā. Pētījuma rezultātā autore sniegs secinājumus un vērtējumu par statusu, kā arī piedāvās priekšlikumus darba ietvaros izsecināto problēmjautājumu risināšanai, lai statusa funkcionēšana kriminālprocesā būtu efektīvāka. Atslēgas vārdi: kriminālprocess, kriminālprocesuālais statuss, persona, pret kuru uzsākts kriminālprocess, tiesības uz aizstāvību.The master's thesis "Person against whom criminal proceedings have been initiated" is devoted to the study of criminal procedural status and the analysis of problem questions. In the criminal procedure system of Latvia, this status is completely new and was introduced together with the Law on Criminal Procedure. The work also draws attention to the right to defense, which was the basis for the legislator to create such a status and ensure this right also for the person against whom the evidence obtained is of the lowest size. The aim of the master's thesis is to investigate the creation and inclusion of criminal procedural status in the Latvian criminal procedure system, to examine the concept and general characteristics of the status and the analysis of the moment of acquisition and termination of the person status. The author will also assess the rights and obligations that arise when a person acquires this criminal procedural status, as well as determine whether such a status or similar exists in the regulations of the criminal procedural laws of other countries. As a result of the research, the author will provide conclusions and an assessment of the status, as well as offer proposals for solving problems identified within the thesis, so that the functioning of the status in the criminal proceedings is more effective. Keywords: criminal procedure, criminal procedural status, person against whom criminal proceedings have been initiated, right to a defense

Enhancing specific capacitance and energy density in printed supercapacitors: The role of activated wood carbon and electrolyte dynamics

This project, funded by the European Commission's Horizon Europe programme, is part of the Graphene Flagship initiative which works to advance technologies that rely on graphene and other 2D materials. Part of the research uses Academy of Finland Research Infrastructure 'Printed Intelligence Infrastructure' (PII-FIRI, Grant Number 358618). SEM images were obtained by Ph.D. Guna Krieķe at the Insitute of Solid State Physics, University of Latvia that has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2.This study investigates Activated Wood Carbon (AWC) as an electrode material for advancing printed supercapacitors (SCs). AWC, derived from biomass, offers a sustainable alternative to conventional activated carbons. The research highlights the interplay between AWC's structural properties and electrolyte compatibility, addressing challenges in energy storage technologies. Comprehensive analyses, including sorptometry, Raman spectroscopy, X-ray diffraction (XRD), and electrochemical assessments, reveal that AWC's graphitization and structural ordering significantly influence its performance. Printed SCs fabricated with AWC demonstrate superior performance compared to those using benchmark Kuraray YP-80F activated carbon, achieving up to 93 % and 90 % higher specific capacitance and energy density at 1.0 V and 1.2 V, respectively. The enhanced performance is attributed to AWC's increased surface area and pore volume, which provide abundant ion storage sites and improve ion mobility. Furthermore, the porous structure of AWC facilitates better compatibility with KxHyPO4 electrolytes compared to NaCl, with pseudocapacitive effects also contributing to the improved energy storage behavior. This work underscores the potential of biomass-derived carbon materials in creating high-performance, sustainable SCs. Future efforts will focus on optimizing electrode and electrolyte configurations to further enhance device performance, supporting the transition toward renewable energy solutions. © 2024 The Author(s) --//-- This is an open-access article Hamed Pourkheirollah, Remuel Isaac M. Vitto, Aleksandrs Volperts, Steffen Thrane Vindt, Līga Grīnberga, Gints Kučinskis, Jari Keskinen, Matti Mäntysalo, Enhancing specific capacitance and energy density in printed supercapacitors: The role of activated wood carbon and electrolyte dynamics, Carbon Trends, Volume 18, 2025, 100436, ISSN 2667-0569, https://doi.org/10.1016/j.cartre.2024.100436 published under the CC BY-NC-ND licence.European Commission's Horizon Europe programme 358618; EU Horizon Europe 101120677, project ARMS; European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 739508, project CAMART2

Promocijas darbs

Elektroniskā versija nesatur pielikumusPromocijas darba tēma ir saistīta ar pašvaldībām, politisko līderi un līderību. Pētījuma pamatā ir problēmjautājumi par vietējo politisko līderu lomu pārvaldības sistēmā un par iespējām nodrošināt un nepieciešamības gadījumā uzlabot pašvaldības domes priekšsēdētājam noteikto uzdevumu izpildi Latvijas pašvaldībās. Promocijas darba mērķis ir, pirmkārt, noskaidrot, kāda ir vietējo politisko līderu loma Latvijas pašvaldībās, otrkārt, sniegt analītisku vērtējumu par politisko līderību Latvijas pašvaldībās un iespējamos uzlabojumus pašvaldības darbību regulēšanā. Latvijas vietējā pārvaldība ir būtiski attīstījusies kopš neatkarības iegūšanas, pārejot no centralizētas uz decentralizētu pieeju, piešķirot domes priekšsēdētājiem politiskās līderības elementus. Neskatoties uz sniegtajām iespējām, domes priekšsēdētāja ietekmi bieži ierobežo ārējie faktori, proti, dalīta pārvaldība un nepieciešamība sadarboties ar dažādām ieinteresētajām pusēm. Līderības īstenošana pašvaldībās ir atkarīga no spējas pārvarēt budžeta izaicinājumus, veicināt sadarbību ar valsts līmeņa dalībniekiem un saskaņot rīcībpolitiku ar iedzīvotāju interesēm. Darbā izmantota gadījumu analīzes metode, sekundāro datu analīze un novērojumu metode. Tostarp izmantoti arī orģinālie dati. Atslēgas vārdi: politiskais līderis, politiskā līderība, pašvaldībasThe subject of the study is local political leadership and local governance. The study is based on questions concerning the role of local political leaders in the local governance system and the possibilities of ensuring and, if necessary, improving the performance of the tasks assigned to the city council in Latvian municipalities. The research examines local political leaders' role in Latvian municipalities. The second aim is to provide a comprehensive evaluation of political leadership in Latvian municipalities, as well as potential enhancements to the functioning of local governments. Latvia's local governance has evolved significantly since independence, with a shift from centralized to decentralized approach, granting mayors significant political leadership roles. Despite these opportunities, a mayor’s influence is often constrained by external factors, shared governance, and the need to engage diverse stakeholders. Leadership in municipalities depends on the ability to navigate budgetary challenges, foster collaboration with national-level actors, and align policies with community priorities. The study uses secondary data analysis, case studies, observation methods of data collection and primary data were also used. Keywords: political leader, political leadership, municipalities

Problems of Application of the Social Hate and Intolerance Composition

Pēdējo gadu laikā publiskajā telpā ir izskanējušas ziņas, ka arvien vairāk ir pieaudzis to personu skaits, kuras cieš no naida noziegumiem. Jānorāda, ka tieši noziegumi, kas vērsti pret kādu konkrētu sociālo grupu ir ar augstāku kaitīguma pakāpi kā individuāli nodarījumi, kas vērsti pret personu. Lai arī personu skaits, kas cieš no šāda veida noziegumiem ar katru gadu palielinās, atbilstoši statistikai, uzsākto kriminālprocesu skaits pēc Krimināllikuma 150. panta ar katru gadu samazinās. Autore bakalaura darbā “Sociālā naida un nesaticības izraisīšanas sastāva piemērošanas problemātika” analizēs jēdziena “naida noziegums” saturu, vienlaikus atspoguļos arī starptautisko, kā arī Latvijas krimināltiesisko regulējumu naida noziegumu kontekstā. Papildus autore sniegs ieskatu atsevišķu ārvalstu krimināltiesiskajā regulējumā, tostarp norādīs uz problemātiku mūsu valsts regulējumā. Atslēgas vārdi: naids, naida noziegums, sociālā naida un nesaticības izraisīšana, sociālās grupas.In recent years, it has been reported in the public space that there has been an increase in the number of people who are being affected by hate crimes. It is important to emphasize that crimes directed against a specific social group are more harmful than individual crimes directed against a person. Although the number of persons suffering from this type of crime is increasing every year, according to statistics, the number of criminal proceedings initiated under Article 150 of the Criminal Law is decreasing every year. The author will analyse the scope of the term "hate crime" in her bachelor's thesis "Problems of Application of the Social Hate and Intolerance Composition", while also reflecting on the international as well as the Latvian legal framework in the context of hate crimes. In addition, the author will provide an insight into the criminal law framework of certain foreign countries, including the problematic aspects of the Latvian framework. Keywords: hate, hate crime, incitement to social hatred and hatred, social groups

Temperature-dependent luminescence of europium-doped Ga₂O₃ ceramics

This research was funded by Committee of Science of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP14972858). M.G.B. thanks the support from the Specialized Funding Program for the Gathering of 100 Elite Talents in Chongqing and the Overseas Talents Plan (Grant No. 2022 [60]) both offered by Chongqing Association for Science and Technology, the Polish NCN projects 2021/40/Q/ST5/ 00336, the Estonian Research Council grant (PRG 2031), and the Ministry of Science, Technological Development, and Innovation of the Republic of Serbia under contract 451-03-47/2023 01/200017. In addition, Marina Konuhova was supported by Latvian research project lzp-2023/1–0453 “Prediction of long-term stability of functional materials under extreme radiation conditions” and Latvian State Research Programme on Nr. VPP-IZM-CERN-2022/1-0001. Institute of Solid State Physics, University of Latvia, as the Center of Excellence, has received funding from the European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. This research was carried out at P66 beamline at PETRA III. Beamtime was allocated for proposals I-20231138. We are thankful to the manager of P66 beamline at PETRA III Aleksei Kotlov for conducting synchrotron experiments.This study explores the synthesis and luminescent properties of europium-doped gallium oxide (Ga₂O₃:Eu) ceramics fabricated via electron beam-assisted synthesis (EBAS) at 1.4 MeV. The resulting Ga₂O₃:Eu ceramics exhibit a nanocrystalline structure with an average crystallite size of ∼30 nm, high crystallinity, and minimal lattice strain (<0.5 %). Luminescence analysis from 4 K to 300 K reveals both intrinsic and europium-induced emissions. While intrinsic Ga₂O₃ emission exhibits thermal quenching above 100 K, Eu³⁺-related emissions, notably the 611 nm red emission, show thermal stability, retaining ∼90 % of their intensity at 300 K. Additionally, a novel low-temperature emission peak at 1.74 eV, potentially associated with electron beam-induced defects, was detected, meriting further exploration. These findings indicate that Ga₂O₃:Eu ceramics synthesized via EBAS hold promise for optoelectronic, radiation detection, and high-temperature applications, given their rapid production and enhanced thermal stability. © 2024 The Author(s) --//-- This is an open-access article Kuat K. Kumarbekov, Askhat B. Kakimov, Zhakyp T. Karipbayev, Murat T. Kassymzhanov, Mikhail G. Brik, Chong-geng Ma, Michał Piasecki, Yana Suchikova, Meldra Kemere, Marina Konuhova, Temperature-dependent luminescence of europium-doped Ga₂O₃ ceramics, Optical Materials: X, Volume 25, 2025, 100392, ISSN 2590-1478, https://doi.org/10.1016/j.omx.2024.100392.Eesti Teadusagentuur PRG 2031; Ministarstvo Prosvete, Nauke i Tehnološkog Razvoja 451-03-47/2023−01/200017; Overseas Talents Plan 2022[60]; Narodowe Centrum Nauki 2021/40/Q/ST5/00336; Ministry of Education and Science of the Republic of Kazakhstan AP14972858; European Union's Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2

Promocijas darbs

Elektroniskā versija nesatur pielikumusPromocijas darbā pētīta dabas parādību pieminējumu skaita dinamika, tostarp īpaši metaforisko lietojumu īpatsvars 20. gadsimta 20.–90. gadu latviešu dzejā. Pieminējumu biežuma noteikšanai izmantotas digitālās pētniecības metodes, metaforas analīzei – konceptuālās metaforas teorijas ietvars. Darbā sniegts ieskats konceptuālās metaforas teorijā, vārdu lietojuma biežuma mērīšanas metodoloģijā un šo virzienu aprobācijā Latvijā. Pētījuma pirmajā posmā analizēti pieminējumu statistiskie dati, kas aptver 389 dzejas krājumus; noteikti 26 dabas parādību, gadalaiku nosaukumu un ar temperatūru saistītu leksēmu pieminējumu biežuma rādītāji laika gaitā. Otrajā posmā veikta ar dabas parādībām saistīto konceptuālo metaforu izpēte un padziļināta “sniega” metaforu mērķjomu analīze, lai noteiktu to konceptuālās struktūras un lietojuma variācijas.The doctoral thesis examines the dynamics in the frequency of mentions of natural phenomena, including the proportion of metaphorical uses, in Latvian poetry from the 1920s to the 1990s. Digital research methods were used to determine word frequencies, while the framework of conceptual metaphor theory was applied for metaphor analysis. The thesis provides an overview of conceptual metaphor theory, the methodology for measuring word usage frequency, and the application of these approaches in Latvia. In the first phase of the research, statistical data on mentions were analyzed, covering 389 poetry collections. Frequency indicators over time were identified for 26 lexical items related to natural phenomena, seasons, and temperature. In the second phase, the study focused on conceptual metaphors associated with natural phenomena, including an in-depth analysis of target domains in "snow" metaphors, to determine their conceptual structures and usage variations