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Nickel nanoprism containing ppm level of Pd catalysis of reduction and Suzuki-Miyaura reactions
No full textTwo types of Nickel nano-prism containing a ppm level of palladium atoms were prepared and their physical morphology and prism-like structure were identified. Catalytic investigation of these novel bimetallic nano-prisms showed that Pd on amine-modified (Ni@NH2-Pd NPr) displayed higher efficiency than one-pot prepared NiPd NPr in reductions of nitroarenes and Suzuki–Miyaura coupling reaction in aqueous media. Using Ni@NH2-Pd NPr with ppm levels of Pd (8 ppm), a variety of aromatic nitro compounds were reduced to amines in very short reaction times and excellent yields. Also, a synergistic effect between ppm of Pd (8 ppm) and Ni NPr was observed in the Suzuki reaction, and different aryl bromides were successfully used as starters in the Suzuki–Miyaura coupling reaction. The catalyst brings out high TON's up to 9090 with respect to Pd species, and recyclability and stability of the catalyst were proved.The authors are grateful to the IASBS Research Council and Alicante University for their support of this work. This work is based upon research funded by Iran National Science Foundation (INSF) under the project no. 4024819. The authors would like to thank the (INSF-Grant number of 4024819), Ministerio de Ciencia, Innovación y Universidades (RED2018–102387-T, PID2019–107268GB-100), and Generalitat Valenciana (IDIFEDER/2021/013) for support of this work
Perfectionism profiles and school-related stress associations: Examining the 2 × 2 model of dispositional perfectionism in children
No full textThe aim of this study was to clarify the relationship between multidimensional perfectionism and school-related stress sources and manifestations in child population using a person-centered approach. The sample consisted of 759 students aged between 8 and 12 years old (M = 9.68, SD = 1.24). The Child and Adolescent Perfectionism Scale and the School Situation Survey were employed. Four perfectionist profiles resulting from the combination between Socially Prescribed Perfectionism (SPP) and Self-Oriented Perfectionism (SOP) were obtained using the quick cluster analysis: Mixed Perfectionism, Pure Self-Oriented Perfectionism, Pure Socially Prescribed Perfectionism and Non-Perfectionism. The Mixed Perfectionism group was the most maladaptive profile, whereas Non-Perfectionism was the most adaptive in terms of stress sources and manifestations in school environments. Results were interpreted considering the model 2 × 2 of perfectionism. Moreover, possible explanations and implications of this study for Educational Psychology were discussed.This study was financed, on the one hand, by the Government of Valencia Ministry of Innovation, Universities, Science, and Digital Society for projects CIGE/2021/021 and CIAICO/2022/078, granted to MV and CG, respectively, and by the predoctoral assistance [CIACIF/2022/252‚ granted to AF. On the other hand, it was financed by the Spanish Ministry of Science, Innovation, and Universities for the project PID2023-152358NA-I00 granted to MV, as well as, with the predoctoral assistance [FPU22/03428] granted to MPM
Stock and corporate bond liquidity: When having the same issuer induces commonality
No full textThis paper evaluates the cross-asset co-movements of the liquidity of stocks and corporate bonds issued by the same firm, revealing a positive and significant contemporaneous relationship between the liquidity of the two assets. This finding is robust to different bond sample selection criteria, alternative methodologies, and various proxies for liquidity. Moreover, the intensity of said relationship depends on both bond and firm risk characteristics. Specifically, we find that the liquidity of bonds in the non-institutional segment of the market and the liquidity of those issued by firms with high financial risk are more strongly connected to stock liquidity shocks.Authors acknowledge the research grant PRPPID2021-125317NB-I00, funded by MCIN/AEI /10.13039/501100011033/ and “ERDF A way of making Europe" and the helpful comments made by the participants at the XXIX Finance Forum and Finance Research Letters 2022 CEMLA Conference
Enhanced catalytic activity of nickel-gold nanoprisms in hydrodesulfurization and reduction of 4-nitrophenol and organic dyes
No full textNickel nano-prism, containing a very low amount of gold (0.16 wt%) (NiAu NPr), was prepared and its physicochemical properties and surface composition were characterized. The catalytic function of this nano-prism was demonstrated in the hydrodesulfurization of thiophene derivatives and the reduction of 4-nitrophenol (4-NP) and organic dyes. Using this catalyst with 0.53 ppm of Au, quantitative reduction and conversion of 4-NP, methyl orange (MO), methyl red (MR), Rhodamine B (RhB), and methylene blue (MB) were achieved immediately. Furthermore, with the NiAu NPr catalyst containing 16 ppm of Au, 3-methylthiophene, dibenzothiophene (DBT), and 4,6-dimethyldibenzothiophene (4,6-DMDBT), the three major sulfur-containing organic pollutants from fuel liquids, were transformed and removed efficiently. Our investigation showed that the presence of Au at the ppm level in the catalyst distinctly improves the catalytic performance and that the NiAu nano-prism has higher activity than the Ni nano-prism and homogeneous Au. Characterization of the recycled catalyst showed that its prism-like structure remained mostly stable during the reactions.The authors are grateful to the IASBS Research Council and Alicante University for their support of this work. This work is based upon research funded by Iran National Science Foundation (INSF) under the project no. 4022486. The authors would like to thank the (INSF-Grant number of 4022486), Ministerio de Ciencia, Innovación y Universidades (RED2018-102387-T, PID2019-107268 GB-100), and Generalitat Valenciana (IDIFEDER/2021/013) for support of this work
Assessment of N-doped carbon microcapsules-based electrochemical capacitors in different electrolytes
No full textThe performance of electrochemical capacitors (ECs) mainly depends on the electrode material and electrolyte. Electrodes are mainly made of carbon materials and organic electrolytes are commonly used in commercial ECs. Environmental concerns have boosted the study of aqueous-based ECs. In this study, nitrogen-doped carbon microcapsules were synthesized by a templating method, obtaining an apparent surface area of 1560 m2 g−1 and a nitrogen content of 5.5 wt%. Such N-doped carbon microcapsules were characterized in a three-electrode configuration to gather information about their electrochemical stability, showing remarkable results in acidic (1 M H2SO4) and neutral (0.5 M Na2SO4) electrolytes. Symmetric ECs based on N-doped carbon microcapsules were assembled and evaluated in both aqueous and organic electrolytes. Ragone plots revealed that N-doped carbon microcapsules-based EC in a neutral electrolyte exhibited good electrochemical performance using an operating voltage of 1.7 V, leading to a capacitance retention (C/C0) of 90% after 10,000 cycles. Additionally, an analogous EC assessed in an organic electrolyte exhibited a noticeable stability compared to that of YP-50F used as electrode material in commercial ECs. The morphology of the carbon materials, as well as the N doping, explain the outstanding performance in the different electrolytes analyzed.This study forms part of the Advanced Materials programme and was supported by MCIN with funding from the European Union NextGenerationEU (PRTR-C17.I1) and by Generalitat Valenciana (MFA/2022/001), DST would like to thank the CIDEGENT 2023 project (Plan GenT) from Generalitat Valenciana (CIDEXG/2023/2) and AEI through the project PID2021–122248OB-I00 (MCIN/AEI /10.13039/501100011033/FEDER, UE)
Analysis of pit craters on asteroids and small bodies: Predictions about the regolith layer and internal structure
No full textIn this work, we investigate and compare potential features called pit craters on the surfaces of (951) Gaspra, (243) Ida, (433) Eros, and the Martian moon, Phobos. Pit craters are typically arranges as chains on the surface and appear to be formed by the drainage of overlying loose material into internal voids promoted by fractures, assessing a piece of direct information about the approximate thickness of the regolith layer, and the internal configuration of each small body. Methodologically, we analyzed images taken by Galileo, NEAR Shoemaker, and other Martian rendezvous missions and mapped these geological morphologies across their surfaces. We analyzed pit sizes using Analysis of Variance and looked for correlations in terms of their different intrinsic physical properties. The pit sizes range between 0.034 and 0.971 km and their estimated regolith layers between 100 and 300 m thick for the four bodies. We demonstrated a strong correlation between the mean diameter of these depressions and the density of the body, making possible a linear model to predict the size of pit craters on small bodies to be visited in future missions, such as Deimos or asteroid (16) Psyche. We also proposed an internal fracturing index for these small bodies that shows a strong correlation with each mean body density. The data provided by future missions for different pitted small objects will allow us to validate or reject these models and predictions.L. M. Parro contribution was supported by the “Margarita Salas” postdoctoral grant (Spanish Ministry of University—NextGenerationEU) and by the CIAPOS/2022/066 postdoctoral grant (European Social Fund. Generalitat Valenciana). LMP acknowledges funding by MICINN (Spain) PGC2021, PID2021- 125883NBC21
Mechanistic assessments of acetaldehyde aldol condensation under capillary condensation within defective Zr-MOFs
No full textChain-growth reactions of light biomolecules are crucial for green chemical processes, among which Guerbet reactions involving acetaldehyde intermediates stand out. This study examines the selective aldol condensation of acetaldehyde towards crotonaldehyde using UiO-66 MOFs modulated with benzoic acid, which highlights the performance over other modulators. Detailed spectroscopic data and DFT simulations reveal unreported catalytically active species. Surface μ1-OH groups are identified as critical active sites for aldol condensation, in synergy with Zr⁴⁺ Lewis acid centers. High selectivity (>90 %) is achieved through the desorption of bound products facilitated by the presence an extended capillary liquid. These findings at low conversion conditions enhance into the understanding of active sites and the capillary effects in defective Zr-MOFs, providing insights for upgrading relevant biomolecules.The authors gratefully acknowledge the financial support from Ministry of Science, Universities and Innovation: project PID2021-122940OB-C33, project PID2021-122940OB-C31 and Basque Government: SUPREN research group with code IT1554-22. We acknowledge the European Synchrotron Radiation Facility (ESRF) for provision of synchrotron radiation facilities under proposal number CH-6737 and CH-6931. We would like to thank Dr. C. Fuller and Dr. D. Chernyshov for assistance and support in using beamline BM01. M.A.O. acknowledges the financial support by MICIU/AEI/10.13039/501100011033 and FSE+ (RYC2022-035453-I, PID2020-119116RA-I00), Xunta Distinguished Researcher program (ED431H 2020/21), the Xunta de Galicia (Centro de Investigación do Sistema Universitario de Galicia accreditation 2023–2027, ED431G 2023/03). This research project was made possible through the access granted by the Galician Supercomputing Center (CESGA) to its supercomputing infrastructure. The supercomputer FinisTerrae III and its permanent data storage system have been funded by the NextGeneration EU 2021 Plan de Recuperación, Transformación y Resiliencia, ICT2021-006904, and also from Programa Operativo Plurirregional de España 2014-2020 of the European Regional Development Fund (ERDF), ICTS-2019-02-CESGA-3, and from Programa Estatal de Fomento de la Investigación Científica y Técnica de Excelencia del Plan Estatal de Investigación Científica y Técnica y de Innovación 2013–2016 (1) Subprograma estatal de infraestructuras científicas y técnicas y equipamiento of ERDF, CESG15-DE-3114
Structural deformation monitoring using UAV photogrammetry to assess slender historic buildings
No full textThis research paper proposes a structural assessment methodology based on the deformation monitoring of slender, tower-type historic buildings. On the basis of the real three-dimensional model of the building, obtained by photogrammetric technique by means of an unmanned aerial vehicle (UAV) in the form of a point cloud, the study and analysis of the research object are conducted by elements, levels and elevations. In order to do this, the point, axes and reference planes are generated, from which virtual control planes (comparison and section planes) are created, which is intended to obtain results that show the events and construction stages that are identified in the existing historical documentation (collapses, differential settlements, twists, eccentricities, and even building corrections), in addition to knowing their current structural state. A deep knowledge of the historical structures makes it possible to implement appropriate intervention and maintenance strategies that guarantee the correct execution of the construction, and hence, the conservation of the architectural heritage.Cathedral measurements were carried out thanks to the support of the “Project (21007/PI/18) financed by the Autonomous Community of the Region of Murcia through the call for Aid to projects for the development of scientific and technical research by competitive groups, included in the Regional Programme for the Promotion of Research (Plan of Action 2019) of the Seneca Foundation, Science and Technology Agency of the Region of Murcia”
A new commonplace: from the classic topos to advertising clichés
No full textEste trabajo aborda la noción de tópico desde sus orígenes en la Retórica y la Poética hasta sus nuevas manifestaciones en el discurso publicitario y poético. Por un lado, la publicidad se apropia de los tópicos clásicos (tempus fugit, carpe diem, memento mori) para transformarlos en mercancía comercial; por otro lado, el ámbito poético aprovecha la tópica publicitaria para generar un diálogo intermedial.Cet article aborde la notion de sujet depuis ses origines en rhétorique et en poétique jusqu’à ses nouvelles expressions dans la publicité et le discours poétique. D’un côté, la publicité s’approprie les lieux communs classiques (tempus fugit, carpe diem, memento mori ) pour les transformer en données marchandes. D’un autre, le champ poétique tire parti de l’expression publicitaire afin de générer un dialogue multimodal.This paper deals with the notion of the topic from its origins in Rhetoric and Poetics to its new expressions in advertising and poetic discourse. On the one hand, advertising appropriates classical clichés (tempus fugit, carpe diem, memento mori) to transform them into commercial merchandise; on the other hand, poetic discourse takes advantage of advertising expression (topoi) to generate a multimodal dialogue