Realisation functors in tilting theory

Derived equivalences and t-structures are closely related. We use realisation functors associated to t-structures in triangulated categories to establish a derived Morita theory for abelian categories with a projective generator or an injective cogenerator. For this purpose we develop a theory of (non-compact, or large) tilting and cotilting objects that generalises the preceding notions in the literature. Within the scope of derived Morita theory for rings we show that, under some assumptions, the realisation functor is a derived tensor product. This fact allows us to approach a problem by Rickard on the shape of derived equivalences. Finally, we apply the techniques of this new derived Morita theory to show that a recollement of derived categories is a derived version of a recollement of abelian categories if and only if there are tilting or cotilting t-structures glueing to a tilting or a cotilting t-structure. As a further application, we answer a question by Xi on a standard form for recollements of derived module categories for finite dimensional hereditary algebras

Internal Logistics Process Improvement using PDCA: A Case Study in the Automotive Sector

Background: The Plan-do-check-act (PDCA) cycle methodology for a continuous improvement project implementation aims for the internal logistics upgrade, which is especially important in the industrial context of a component manufacturing company for the automotive sector. Objectives: The goal is to quantify the gains from waste reduction based on the usage of the PDCA cycle as a tool in the implementation and optimisation of a milk run in an assembly line of a company in the automotive sector by determining the optimal cycle time of supply and the standardisation of the logistic supply process and the materials’ flow. Methods/Approach: The research was conducted through observation and data collection in loco, involving two main phases: planning and implementation. According to the phases of the PDCA cycle, the process was analysed, and tools such as the SIPOC matrix, process stratification, 5S, and visual management were implemented. Results: Using Lean tools, it was possible to reduce waste by establishing concise flows and defining a supply pattern, which resulted in a reduction of movements. The transportation waste was reduced by fixing the position of more than half of the materials in the logistic trailers. The developed Excel simulator provided the logistic train\u27s optimal cycle time. Conclusions: The assembly line supplied by milk-run was fundamental to highlight a range of improvements in the process of internal supply, such as better integration of stock management systems, greater application of quality, or the adoption of better communication systems between the different areas and employees

Linear confinement of a scalar particle in a G\"odel-type spacetime

Based on the studies of confinement of quarks, we introduce a linear scalar potential into the relativistic quantum dynamics of a scalar particle. Then, we analyse the linear confinement of a relativistic scalar particle in a G\"odel-type spacetime in the presence of a topological defect. We consider a G\"odel-type spacetime associated with null curvature, i.e., the Som-Raychaudhuri spacetime, which is characterized by the presence of vorticity in the spacetime. Then, we search for analytical solutions to the Klein-Gordon equation and analyse the influence of the topology of the cosmic string and the vorticity on the relativistic energy levels.Comment: 11 pages, no figure. Accepted for publication in EPJ

Holonomy corrected Schwarzschild black hole lensing

In the present work, we theoretically investigate gravitational lensing in the spacetime of a holonomy corrected Schwarzschild black hole. Analytical expressions for the light deflection angle are obtained in both the weak field limit and the strong field limit. Furthermore, we analyze observables, such as relativistic images and magnifications, and compare the results with those expected in a Schwarzschild spacetime. We discuss the possibilities and difficulties of investigating such a solution in practice

Imidazolium and picolinium-based electrolytes for electrochemical reduction of CO2 at high pressure

ABSTRACT: Ionic liquids (ILs) have been considered among one of the most promising materials under investigation for integration of CO2 capture and electrochemical reduction (ECR). In the design of an IL-based electrolyte that can be employed industrially, the understanding of the influence of IL structure on ECR was considered essential. In this context, electrolytes with trifluoromethanosulfonate (OTf) anion were investigated as aqueous electrolytes for electrochemical reduction of CO2 at high pressure and near room temperature with zinc electrodes. The effect of replacing the 1-ethyl-3-methyl-imidazolium cation [EMIM] by 1-ethyl-3-picolinium [C2(3)pic] and by 1-ethyl-4-picolinium [C2(4)pic] cations was studied. The use of picolinium-based electrolytes in ECR is for the first time reported. A high-pressure single compartment test bed was used for electrolyte screening. Carbon monoxide productivities and selectivities were determined for the several electrolytes with different water contents. The electrolytes were characterized by cyclic voltammetry and electrochemical impedance spectroscopy. Electrolyte conductivities and diffusion coefficients were estimated. The effect of the cations is complex as it affects conductivity, double layer structure, reaction reversibility and even the ionic liquid physical state. Notwithstanding, it is possible to tune these properties to achieve similar CO productions with reduced IL amounts, considering the nature of the cation and the water content, leading to the design of more cost effective electrolytes for efficient ECR process.info:eu-repo/semantics/publishedVersio

New data on the deposition age of the volcano-sedimentary Chela Group and its Eburnean basement : implications to post-Eburnean crustal evolution of the SW of Angola

The Chela Group comprises a volcano-sedimentary sequence deposited in a widespread epicratonic basin that extends to southern of the Lubango region in SW of Angola. The basement rocks of the Chela Group integrate the Eburnean belt, consisting mainly of gneisses and migmatites, syntectonic foliated peraluminous granites, and late-tectonic metaluminous granites of the Chela and Gandarengos Mountains. Rb/Sr radiometric age of 2.1 ± 0.1 Ga was determined for the syntectonic granites whereas the late-tectonic Chela granite yielded a zircon U-Pb age of 1947 ± 5 Ma. This isotopic dating allow us to take it as a maximum age for the Chela Group. Moreover, the porphyritic calc-alkaline granite of the Gandarengos Mountain and a rhyolitic mass, spatially related to this granite, revealed U-Pb zircon ages of 1810 ± 11 Ma and 1814 ± 88 Ma, respectively. The rhyolite is intrusive into Tundavala Formation, base of the Chela Group, and should be the source of the pyroclastites composing the Humpata Formation. The time interval between 1814-1810 Ma obtained for the volcano-plutonism intrusive into the Chela Group restrains its minimum age and permits to define the interval 1947-1810 Ma as the main period of deposition of this sedimentary sequence in a post-orogenic environment. After the deposition of the Chela Group, succeeds a period of crustal accretion marked by the installation of leucocratic peraluminous granites and an extensional Mesoproterozoic (1.4-1.1 Ga) bimodal magmatism, followed during the Neoproterozoic by deposition of the Damara Supergroup and development of the Pan-African belt. At that period, any tectonometamorphic event reportable to Grenville-Kibaran orogeny was not recognized in SW Angola

Estudo Anatomohistopatológico da Paratuberculose em ovinos Serra da Estrela

A Paratuberculose é de uma doença crónica, de difícil diagnóstico, causadora de importantes perdas económicas. Por haver suspeita da sua presença nos efectivos ovinos da região da Serra da Estrela, é fundamental estabelecer um protocolo de diagnóstico rápido, eficaz e fiável, de modo a poderem ser identificados os rebanhos portadores de casos de doença e, posteriormente, elaborar-se um plano que permita o seu controlo. Este trabalho consistiu na aplicação de métodos de diagnóstico anatomopatológicos a 34 animais previamente submetidos a dois testes serológicos, ELISA e AGID, aos quais foi realizada a necrópsia. Assim, foram contemplados vários parâmetros de diagnóstico que incluíram a observação do hábito externo antes da realização da necrópsia, necrópsia, exame histopatológico, método de coloração de Ziehl-Neelsen, bem como o método de Imunohistoquímica, cujos resultados se apresentam. Teve como objectivo o estudo anátomopatológico de uma amostragem de animais soropositivos, negativos e duvidosos, de modo a avaliar o padrão lesional macro e microscópico, a presença de bactérias álcool-ácido-resistentes na coloração de Ziehl-Neelsen, bem como a marcação com o anticorpo anti-MAP, de modo a comparar estes resultados com os da serologia e assim contribuir para o objectivo último de estabelecer um protocolo de diagnóstico rápido, eficaz. Dos trinta e quatro animais enviados para necrópsia, verificou-se que os mesmos apresentaram reacção positiva ao ELISA em dezasseis casos, duvidoso num e foi negativo em doze animais. O AGID foi positivo apenas em quatro animais, e negativa em vinte e seis animais. O exame do hábito externo foi compatível em vinte e sete animais e não compatível em seis animais. O exame macroscópico foi compatível em vinte e oito animais e foi não compatível em três animais. A histopatologia foi compatível em vinte e um animais e foi não compatível em dez animais. Na coloração de Ziehl-Neelsen observaram-se bactérias álcool-ácido resistentes em dezoito animais e não se observaram bactérias álcool-ácido resistentes em treze animais. Na imunohistoquímica dois animais foram positivos.Projecto Agro 786, Medida 8. Desenvolvimento Tecnológico e Demonstração. Acção 8.1-Desenvolvimento Experimental e Demonstração, bem como a todas as entidades nele intervenientes