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Binding interaction of two organoplatinum complexes, [Pt(C^N)Cl(dppa)]

The analysis of the opinions and experiences of tourists is a key issue in tourist promotion. More precisely, forecasting whether a tourist will or will not recommend a given destination, based on his/her profile, is of utmost importance in order to optimize management actions. According to this idea, this research proposes the application of cutting-edge machine learning techniques in order to predict tourist recommendation of rural destinations. More precisely, classifiers based on supervised learning (namely Support Vector Machine, Decision Trees, and [Formula: see text]-Nearest Neighbor) are applied to survey data collected in the province of Burgos (Spain). Available data suffer from a common problem in real-life datasets (data unbalance) as there are very few negative recommendations. In order to address such problem, that penalizes learning, data balancing techniques have been also applied. The satisfactory results validate the proposed application, being a useful tool for tourist managers.

Type V natural deep eutectic solvents based on monoterpenoids (cineole, carvone, menthol, and thymol) are studied using a combined experimental and molecular modeling approach. The reported physicochemical properties showed low viscous fluids whose properties were characterized as a function of temperature. The theoretical study combining quantum chemistry and classical molecular dynamics simulations provided a nanoscopic characterization of the fluids, particularly for the hydrogen bonding network and its relationship with the macroscopic properties. The considered fluids constitute a suitable type of solvents considering their properties, cost, origin, and sustainability in different technological applications and sow the possibility of developing type V NADES from different types of molecules, especially in the terpenoid family of compounds.

Hydrogen is one of the clean energy sources that can be used instead of fossil fuel sources to reduce greenhouse emissions. However, hydrogen supply intermittency significantly reduces the deployment and reliability of this energy resource. Therefore, this work investigates the underground storage of hydrogen in depleted gas reservoirs to avoid seasonal fluctuations in hydrogen supply and assure long-term energy security. The obtained results from molecular simulation (Density Functional Theory) revealed hydrogen is adsorbed physically on calcite (104) and silica (001) surfaces on different adsorption configurations. This conclusion is supported by low adsorption energies (−0.14 eV for calcite and −0.09 for silica) and by Bader charge analysis, which showed no indication of charge transfer. The experimental results illustrated that hydrogen has a very low adsorption affinity toward carbonate and sandstone rocks in the temperature range of 50–100 °C and pressure up to 20 bar. These results show the potential of depleted gas reservoirs to store hydrogen for s is useful in hydrogen recovery as no hydrogen will be adsorbed to the rock surface of conventional gas reservoirs. The authors would like to acknowledge the Qatar National Research Fund (a member of Qatar Foundation) for funding through Grant # NPRP13S-1231-190009. Al-Salam Petroleum Services Company, Qatar, is also acknowledged for co-funding this project. The findings achieved herein are solely the responsibility of the authors. The authors would also like to acknowledge Qatar University for providing support. Scopus

The development of powerful computers and molecular simulation has allowed researchers to use them to get useful information about electronic properties related to chemical and physical interactions at the molecular level. In addition, statistical analysis done by molecular simulation could be used to provide fluid properties for large-scale systems comparable to the experimental results. Hence, molecular simulation has been used recently in different fields, including oil and gas applications, as it can investigate the pore-scale properties considering nano-, micro-, and macro-scale parameters such as adsorption, transport, and phase behaviors. This chapter contains an introduction and background information for readers who are not familiar with molecular simulation methods. Furthermore, the chapter sheds light on the application of molecular simulation in oil and gas studies specifically (enhanced oil/gas recovery, estimation of ultimate recovery, scale inhibition/removal), giving the details on how the fluid-solid interactions are addressed with a few examples from literature. 2023 Elsevier B.V. The authors would like to acknowledge the support of the Qatar National Research Fund (a member of the Qatar Foundation) through Grant # NPRP11S-1228-170138. Furthermore, the authors acknowledge the funds provided by Qatar University provided through the Internal Grant # QUCP-CENG-2021-03. Scopus

A theoretical study using Density Functional Theory and classical Molecular Dynamics simulations for the study of carbon nanomaterials in archetypical Menthol + Thymol Type V Natural Deep Eutectic Solvent is reported. The nanoscopic structure of the representative nanofluid is analyzed considering confinement, adsorption and solvation effects, as well as consequences on diffusion properties through nano pores. Different types of nanomaterials were considered such as fullerenes, nanotubes, graphene and nanopores. The study of nanoscopic properties allowed to analyze the response of the solvent to the presence of the nanomaterials, taking into account solvent rearrangement and confinement in nanocavities and surfaces. This response shows liquid structure and mobility consequences, with a sort of nano-Venturi effect among them. The reported results provide for the first time a characterization of this type of natural solvents as a sustainable platform for the development of carbon – nanomaterials-based technologies.

The GRACIOUS Framework (www.h2020gracious.eu) supports the grouping of nanomaterials to streamline hazard testing of nanomaterials. The GRACIOUS Framework includes a template to generate grouping hypotheses based upon use and life cycle stage (to inform exposure route), physicochemical properties (what they are), fate or toxicokinetics (where they go) and hazard (what they do). The gathering of evidence to test these hypotheses was supported by tailored Integrated Approaches to Testing and Assessment (IATAs). Subsequent NMBP-16 projects have developed the hypothesis template further for multicomponent nanomaterials. Modifications include additional information requirements to accommodate the complexity of composition (what they are) and enhanced properties, with an aim to incorporate the relationship of these to the mechanism of hazard. Furthermore, the template considers potential for the components to dissociate, disintegrate or dissolve, with different kinetics, leading to a complex exposure scenario both in lung lining fluid and inside cells. This knowledge informs the hazard assessment (whether hazard is driven by the intact multicomponent nanomaterial or various components) and whether interactions between the components may lead to antagonism, synergism or potentiation of response. Hazard assessment outcome can then inform Safe-by-Design modifications. The template has been adapted to formulate clear questions needed to test all aspects of the hypothesis, with these questions being used to formulate the IATA. Case studies of different multicomponent nanomaterials are being used to inform the design process, and demonstrate its usefulness. Funding acknowledgement European Commission Horizon 2020 for GRACIOUS, SUNSHINE, HARMLESS and DIAGONAL, Grant Agreement No. 760840, 952924, 953183 953152 respectively.

During the Mexican War of Independence (1810-1821), the Oaxaca Intendancy showed great loyalty to the Spanish King Fernando VII, despite the occupation of its territory by the insurgent forces during two years. And, once Mexico’s independence was accomplished in 1821, certain popular sectors kept showing loyalty to the Spanish Crown. Based on research of judicial files, this article analyzes diverse outcries of adherence to the Spanish Crown in drunken situations in the Intendancy of Oaxaca, as well as the reactions of both members of society and the Mexican government, the former filing lawsuits, and the latter thriving to eradicate any clue of the colonial past.

Sustainable technologies applied to energy-related applications should develop a pivotal role over the next decades. Therefore, the development of new materials for old processes has merged as a central research line lately. Deep eutectic solvents (DESs) have been recently considered alternative and economic task-specific solvents for many chemical and environmental processes. The low-cost production of DESs production from natural sources and their tunable properties, such as neat null toxicity and biodegradability, make these solvents suitable candidates for various processes within the green chemistry framework. Considering the millions of possible DES combinations yet to be explored, a detailed review of DES research’s current status that can elaborate on the structure–property relationship is an essential task to identify the missing links and strong points on DES research. Thus, this review work focuses on the recent research efforts on the utilization of DES on chemical processes, with the purpose of elucidation on gas capture/separation, fuel desulfurization, biodiesel production, and water treatment processes and provides a deeper understanding on outstanding scientific questions and identifies promising new research directions that involve DESs., Ministerio de Ciencia, Innovación y Universidades (Spain, Project No. RTI2018-101987-B-I00) and Western Michigan University Research Fund (No. 11-1211410-4850).

The chemical exfoliation of graphite in liquids is the choice method to produce few-layer graphenes with versatility and scalability. While physical mechanisms have been described, the understanding of the graphene-medium interactions at the molecular level is still a challenge. Here, a systematic experimental and theoretical investigation of factors that control the chemical exfoliation of graphite into graphene was performed using 1-cyclohexyl-2-pyrrolidone (CHP)/water mixtures as model systems. The “molecular wedge” structure of CHP and the reduction of graphene-CHP interfacial energy are critical factors in the exfoliation of graphite, but they are not sufficient for the stabilization of the isolated graphene sheets. We propose that such stabilization occurs by steric forces with the formation of a sandwich-like structure on the surface of graphene with two layers of water molecules interleaved with a monolayer of CHP, and by electrostatic forces resulting from the hybrid surface polarization due to the CHP/H2O-graphene interaction. This stabilization is hampered in CHP/H2O mixtures containing above 10 wt% CHP due to the formation of CHP–CHP aggregates.

Lithium silicates have attracted great attention in recent years due to their potential use as high-temperature (450-700 °C) sorbents for CO

Coronary atherosclerosis is the main cause of death worldwide. Advancing the understanding of coronary microstructure-based mechanics is fundamental for the development of therapeutic tools and surgical procedures. Although the passive biaxial properties of the coronary arteries have been extensively explored, their regional differences and the relationship between tissue microstructure and mechanics have not been fully characterized. In this study, we characterized the passive biaxial mechanical properties and microstructural properties of the proximal, medial, and distal regions of the porcine left anterior descending artery (LADA). We also attempted to relate the biaxial stress-stretch response of the LADA and its respective birefringent responses to the polarized light for obtaining information about the load-dependent microstructural variations. We found that the LADA extensibility is reduced in the proximal-to-distal direction and that the medial region exhibits more heterogeneous mechanical behavior than the other two regions. We have also observed highly dynamic microstructural behavior where fiber families realign themselves depending on loading. In addition, we found that the microstructure of the distal region exhibited highly aligned fibers along the longitudinal axis of the artery. To verify this microstructural feature, we imaged the LADA specimens with multi-photon microscopy and observed that the adventitia microstructure transitioned from a random fiber network in the proximal region to highly aligned fibers in the distal region. Our findings could offer new perspectives for understanding coronary mechanics and aid in the development of tissue-engineered vascular grafts, which are currently limited due to their mismatch with native tissue in terms of mechanical properties and microstructural features. STATEMENT OF SIGNIFICANCE: The tissue biomechanics of coronary arteries is fundamental for the development of revascularization techniques such as coronary artery bypass. These therapeutics require a deep understanding of arterial mechanics, microstructure, and mechanobiology to prevent graft failure and reoperation. The present study characterizes the unique regional mechanical and microstructural properties of the porcine left anterior descending artery using biaxial testing, polarized-light imaging, and confocal microscopy. This comprehensive characterization provides an improved understanding of the collagen/elastin architecture in response to mechanical loads using a region-specific approach. The unique tissue properties obtained from this study will provide guidance for the selection of anastomotic sites in coronary artery bypass grafting and for the design of tissue-engineered vascular grafts.

The protection of natural areas is considered an essential strategy for environment conservation. The objective of this work was to determine the level of vulnerability, considering the characterization and identification of the risk zones and ecological protection of the Pagaibamba Protection Forest (PPF, Peru). To determine the vulnerable areas, Landsat ETM satellite images, topographic, geological, ecological, and vegetation cover maps were used. Geological, physiographic, edaphological, vegetation cover, and land use potential characteristics, were analyzed. Three Ecological Protection and Risk Zones were identified, with the largest extension of the PPF corresponding to lands of very high and high vulnerability and high ecological risk, which include >85% of Protected Natural Areas (PNA) and 54% of the Buffer Zone (BZ). Moderate risk areas represent 30% of the Buffer Zone (BZ) and 13% of the PNA, and the low-risk areas (represent 15% of the BZ and 2% of the PNA). Biogeographically, the PPF was related to the Cloudy Montane Forests Ecoregion of the Andes Mountains, standing out the Tropical Montane Cloud Forest (TMCF) and the Tropical Lower Montane Cloud Forest (TLMCF). These forests are a global conservation priority due to their great biodiversity, high level of endemicity of flora and fauna, and the crucial hydrological function they fulfill.

Type V natural deep eutectic solvents considering menthol, thymol, and levulinic acids are studied considering a combined experimental and theoretical approach to develop a multiscale characterization of these fluids with particular attention to intermolecular forces (hydrogen bonding) and their relationships with macroscopic behavior. Density, viscosity, refraction index, and thermal conductivity were measured as a function of temperature, providing a thermophysical characterization of the fluids. Quantum chemistry was applied to characterize hydrogen bonding in minimal molecular clusters, allowing us to quantify interaction strength, topology (according to atoms in a molecule theory), and electronic properties. Classical molecular dynamics simulations were also performed, allowing us to characterize bulk liquid phases at the nanoscopic level, analyzing the fluid’s structuring, void distribution, and dynamics. The reported results allowed us to infer nano–macro relationships, which are required for the proper design of these green solvents and their application for different technologies.

This work explores determinants of public satisfaction with urban solid waste collection service quality of the city of Burgos (Spain). A Structural Equation Modeling is conducted based on the indicators of the service quality offered by the SEMAT S.A. company and the dimensions offered by SERVQUAL service quality model. The findings show that Assurance and Responsiveness have a positive and significant effect on public satisfaction. However, Reliability, Empathy, and Tangible have no significant effect. Regarding Assurance, cleanliness of pavements and cleanliness of walkways are the indicators that provide a significant influence on this dimension. Otherwise, daily collection of organic waste and daily collection of selective waste are the indicators that provide a significant effect on the Responsiveness dimension. We can emphasize that increasing public satisfaction can be achieved by increasing the frequency of pavements and walkways cleanliness and the frequency of organic and selective waste collection and that this has a clear relationship with the increase in costs and pollution impact. Find a balance between frequency of collection and cost and pollution is necessary. Despite this, the significance of these indicators is strong enough to motivate decision-makers to address their efforts and investments in improving them, enabling thus an effective and efficient service at the required level of quality and adjusting their strategies to increase public satisfaction. Moreover, the study highlights that 84.37% of citizens are satisfied with the service. In addition to this practical validation at the management level, we also discuss environmental and sustainability repercussions.

The solvation of two different antibiotics (ampicillin and piperacillin) in three newly designed arginine-based deep eutectic solvents (DESs) is studied using computational chemistry methods: molec...

The properties of the betaine + lactic acid deep eutectic solvent were studied using combined experimental and computational methods. The effects of betaine + lactic acid mole ratio, water content, and temperature on the properties of the fluids and microscopic structuring were analyzed in this work. Computational studies using quantum chemistry and classical molecular dynamics simulations allowed an analysis of the characteristics of intermolecular forces, particularly for hydrogen bonding, molecular arrangements in the liquid phases, and their role on fluid’s properties. The considered deep eutectic properties can be fine-tuned through variations in the mole ratios and water content, thus increasing the suitability of this fluid for industrial applications.

The properties of carbon, boron nitride, silicon, germanium, and molybdenum disulfide nanotubes in reline (cholinium chloride + urea) deep eutectic solvents were studied by using classical molecular dynamics simulations. These nanotubes + reline nanofluids provide a suitable platform for the development of sustainable thermal engineering applications. The reported results lead to the characterization of nanotube solvation and reline layering around the nanotube surfaces as well as the behavior of reline upon confinement inside the considered nanotube cavities. Changes in reline hydrogen bonding in the presence of the nanotubes are also analyzed and related with the development of stable nanotube dispersions, thus showing reline as a suitable vehicle for nanotubes.