Vulnerability of Identity and Memory: Jasenovac, Ricoeur, and the Death of God

This paper was created as a result of discussions with the students from the Evangelical Theological Seminary in Osijek, as part of the Introduction into Philosophy course. In the paper we used parts of Luka Đukić’s essay, “Memorial Centers: The Role of Memory,” which have, as part of dialogue regarding the role of memory, been inserted into the text by J. Mladenovska-Tešija. The purpose of the paper is to emphasize the relevance of Ricoeur’s reflections about memory for Evangelical Christians, especially considering Christ’s death on Calvary as an anti-narrative

Ranjivost identiteta i pamćenja: Jasenovac, Ricoeur i smrt Boga

Ovaj je rad nastao kao rezultat diskusija koje su se vodile sa studentima Visokoga evanđeoskoga teološkog učilišta u Osijeku, u okviru kolegija Uvod u filozofiju. U radu su korišteni dijelovi eseja studenta Luke Đukića “Memorijalni centri: uloga pamćenja” koji su, u cilju dijaloga o ulozi pamćenja, umetnuti unutar teksta J. Mladenovske-Tešije. Cilj je rada ukazati na relevantnost Ricoeurova razmišljanja o pamćenju za evanđeoske kršćane, posebice imajući u vidu Kristovu smrti na Golgoti kao protunarativ

Current State of Dynamic Vehicle Routing Problems Solved by Ant Colony Optimization Algorithm

Dynamic Vehicle Routing Problem is a more complex version of Vehicle Routing Problem, closer to the present, real-world problems. Heuristic methods are used to solve the problem as Vehicle Routing Problem is NP-hard. Among many different solution methods, the Ant Colony Optimization algorithm is proven to be the efficient solution when dealing with the dynamic version of the problem. Even though this problem is known to the scientific community for decades, the field is extremely active due to technological advancements and the current relevance of the problem. As various sub-types of routing problems and solution methods exist, there is a great number of possible problem-solution combinations and research directions. This paper aims to make a focused review of the current state in the field of Dynamic Vehicle Routing Problems solved by Ant Colony Optimization algorithm, to establish current trends in the field

Understanding the Crucial Significance of the Temperature and Potential Window on the Stability of Carbon Supported Pt-alloy Nanoparticles as Oxygen Reduction Reaction Electrocatalysts

The present research provides a comprehensive study of carbon-supported intermetallic Pt-alloy electrocatalysts and assesses their stability against metal dissolution in relation to the operating temperature and the potential window using two advanced electrochemical methodologies: (i) the in-house designed high-temperature disk electrode (HT-DE) methodology as well as (ii) a modification of the electrochemical flow cell coupled to an inductively coupled plasma mass spectrometer (EFC-ICP-MS), allowing for highly sensitive time- and potential-resolved measurements of metal dissolution. The findings contradict the generally accepted hypothesis that in contrast to the rate of carbon corrosion, which follows the Arrhenius law and increases exponentially with temperature, the kinetics of Pt and subsequently the less noble metal dissolution are supposed to be for the most part unaffected by temperature. On the contrary, clear evidence is presented that in addition to the importance of the voltage/potential window, the temperature is one of the most critical parameters governing the stability of Pt and thus, in the case of Pt-alloy electrocatalysts also the ability of the nanoparticles (NPs) to retain the less noble metal. Lastly, but also very importantly, results indicate that the rate of Pt redeposition significantly increases with temperature, which has been the main reason why mechanistic interpretation of the temperature-dependent kinetics related to the stability of Pt remained highly speculative until now

A meta-analysis excerpt: Is exposure to environmental pollutants associated with pancreatic cancer?

Istraživanje u oblasti karcinoma pankreasa i zagađivača iz životne sredine sve je intenzivnije. Za neke od ovih zagađivača pretpostavlja se da su povezani sa nastankom ili progresijom karcinoma pankreasa. Nijedna meta-analiza o povezanosti navedenog nije sprovedena, dok bi rezultati iste mogli pomoći u tumačenju dostupnih podataka i usmeravanju budućeg istraživanja. ...There is a rise in research on the connection between pancreatic cancer and environmental pollutants. Some of these pollutants are assumed to be associated with the onset or progression of pancreatic cancer. No meta-analyses summarizing the association between these two have been conducted yet, while the results of such an analysis could help interpret current and guide future research. ..

Adjusting the operational potential window as a tool for prolonging the durability of carbon-supported Pt-alloy nanoparticles as oxygen reduction reaction electrocatalysts

A current trend in the investigation of state-of-the-art Pt-alloys as proton exchange membrane fuel cell (PEMFC) electrocatalysts is to study their long-term stability as a bottleneck for their full commercialization. Although many parameters have been appropriately addressed, there are still certain issues that must be considered. Here, the stability of an experimental Pt-Co/C electrocatalyst is investigated by high-temperature accelerated degradation tests (HT-ADTs) in a high-temperature disk electrode (HT-DE) setup, allowing the imitation of close-to-real operational conditions in terms of temperature (60 °C). Although the US Department of Energy (DoE) protocol has been chosen as the basis of the study (30,000 trapezoidal wave cycling steps between 0.6 and 0.95 V$_{RHE}$ with a 3 s hold time at both the lower potential limit (LPL) and the upper potential limit (UPL)), this works demonstrates that limiting both the LPL and UPL (from 0.6−0.95 to 0.7−0.85 V$_{RHE}$) can dramatically reduce the degradation rate of state-of-the-art Pt-alloy electrocatalysts. This has been additionally confirmed with the use of an electrochemical flow cell coupled to inductively coupled plasma mass spectrometry (EFC-ICP-MS), which enables real-time monitoring of the dissolution mechanisms of Pt and Co. In line with the HT-DE methodology observations, a dramatic decrease in the total dissolution of Pt and Co has once again been observed upon narrowing the potential window to 0.7−0.85 V$_{RHE}$ rather than 0.6−0.95 V$_{RHE}$. Additionally, the effect of the potential hold time at both LPL and UPL on metal dissolution has also been investigated. The findings demonstrate that the dissolution rate of both metals is proportional to the hold time at UPL regardless of the applied potential window, whereas the hold time at the LPL does not appear to be as detrimental to the stability of metals

Adjusting the Operational Potential Window as a Tool for Prolonging the Durability of Carbon-supported Pt-alloy Nanoparticles as Oxygen Reduction Reaction Electrocatalysts

A current trend in the investigation of the state-of-the-art Pt-alloys as the proton exchange membrane fuel cells (PEMFCs) electrocatalysts is to study their long-term stability as a bottleneck for their full commercialization. Although many parameters have been appropriately addressed, there are still certain issues that must be considered. Here, the stability of an experimental Pt-Co/C electrocatalyst is investigated by high-temperature accelerated degradations tests (HT-ADTs) in a high-temperature disc electrode (HT-DE) setup, allowing the imitation of close-to-real operational conditions in terms of temperature (60 ℃). Whereas the US Department of Energy (DoE) protocol has been chosen as the basis of the study (30 000 trapezoid-wave cycling steps between 0.6–0.95 VRHE with a 3 s hold time at both the lower potential limit (LPL) and the upper potential limit (UPL)), this works demonstrates that limiting both the LPL and UPL (from 0.6–0.95 VRHE to 0.7–0.85 VRHE) can dramatically reduce the degradation rate of state-of-the-art Pt-alloy electrocatalysts. This has been additionally confirmed with the use of an electrochemical flow cell coupled to an inductively coupled plasma mass spectrometry (EFC-ICP-MS), which enables real-time monitoring of the dissolution mechanisms of Pt and Co. In line with the HT-DT methodology observations, a dramatic decrease in the total dissolution of Pt and Co has once again been observed upon narrowing the potential window to 0.7–0.85 VRHE rather than 0.6–0.95 VRHE. Additionally, the effect of the potential hold time at both LPL and UPL on the metal dissolution has also been investigated. The findings demonstrate that the dissolution rate of both metals is proportional to the hold time at UPL, regardless of the applied potential window, while the hold time at the LPL does not appear to be as detrimental to the stability of metals. Nevertheless, the total dissolution of metals has been once again significantly lower for the narrower potential window of 0.7–0.85 VRHE rather than 0.6–0.95 VRHE

Correlating oxygen functionalities and electrochemical durability of carbon supports for electrocatalysts

Achieving high durability of the polymer electrolyte membrane (PEM) fuel cell catalysts remains a major challenge. While most of the research focuses on the active phase, carbon support remains overlooked. In this study durability of carbon support materials for Pt alloy nanoparticles is critically evaluated. First graphene derivative (GD) based carbon supports with different chemical properties are prepared and utilized along with widely used commercial carbon black (CB) material. High-temperature electrochemical accelerated degradation tests (HT-ADTs) combined with X-ray photoelectron spectroscopy (XPS) show that the total amount of oxygen functionalities, the type of oxygen functionalities, and sp$^2$ carbon content play a crucial role in carbon support durability. The observations were confirmed with the direct online measurements of carbon corrosion via an advanced in-situ technique – an electrochemical cell coupled with a mass spectrometer (EC-MS). We report that increasing the content of sp$^2$ carbon and decreasing carboxyl functional groups have the most beneficial effect on stability. The study provides important guidelines for tailoring the carbon support properties and their relationship to the durability of the electrocatalyst, which could be crucial for producing more stable catalysts and achieving the Department of Energy’s fuel cell system lifetime targets. Moreover, the innovative carbon design approach presented here could be applied in other fields such as batteries, supercapacitors, sensors and others

Graphene-derived carbon support boosts proton exchange membrane fuel cell catalyst stability

The lack of efficient and durable proton exchange membrane fuel cell electrocatalysts for the oxygen reduction reaction is still restraining the present hydrogen technology. Graphene-based carbon materials have emerged as a potential solution to replace the existing carbon black (CB) supportshowever, their potential was never fully exploited as a commercial solution because of their more demanding properties. Here, a unique and industrially scalable synthesis of platinum-based electrocatalysts on graphene derivative (GD) supports is presented. With an innovative approach, highly homogeneous as well as high metal loaded platinum-alloy (up to 60 wt %) intermetallic catalysts on GDs are achieved. Accelerated degradation tests show enhanced durability when compared to the CB-supported analogues including the commercial benchmark. Additionally, in combination with X-ray photoelectron spectroscopy Auger characterization and Raman spectroscopy, a clear connection between the sp$^2$ content and structural defects in carbon materials with the catalyst durability is observed. Advanced gas diffusion electrode results show that the GD-supported catalysts exhibit excellent mass activities and possess the properties necessary to reach high currents if utilized correctly. We show record-high peak power densities in comparison to the prior best literature on platinum-based GD-supported materials which is promising information for future application

Sulforaphane and sulforaphane - glucosinolate toxicity prediction using the in silico US-EPA COMPTOX chemicals DASHBOARD method

In silico metode u toksikologiji podrazumevaju upotrebu kompjuterskih metoda koje omogućavaju analizu i predviđanje toksičnosti supstanci, pri čemu mogu usmeriti dalja eksperimentalna istraživanja. Sulforafan (SFN) je organosumporna supstanca iz grupe izotiocijanata, prisutna u povrću krstašica. Dok se SFN-glukozinolat ekstrahuje iz brokolija i uključen je u brojne kliničke studije, SFN je hemijski sintetisan i koristi se samo u istraživačke svrhe. ...In silico methods in toxicology use computer methods to analyze and predict the toxicity of substances, which can serve as a basis for further experimental studies. Sulforaphane (SFN) is an organosulfur chemical from the isothiocyanate group, present in cruciferous vegetables. While SFN-glucosinolate is extracted from broccoli and is presently ongoing numerous clinical studies, SFN has been chemically synthetized, currently only for research purposes. ..