Anomalous transient blueshift in the internal stretch mode of CO/Pd(111)

In time-resolved pump-probe vibrational spectroscopy the internal stretch mode of polar molecules is utilized as a key observable to characterize the ultrafast dynamics of adsorbates on surfaces. The adsorbates non-adiabatic intermode couplings are the commonly accepted mechanisms behind the observed transient frequency shifts. Here, we study the CO/Pd(111) system with a robust theoretical framework that includes electron-hole pair excitations and electron-mediated coupling between the vibrational modes. A mechanism is revealed that screens the electron-phonon interaction and originates a blueshift under ultrafast non-equilibrium conditions. The results are explained in terms of the abrupt change in the density of states around the Fermi level, and are instrumental for understanding dynamics at multi-component surfaces involving localized and standard $s$ or $p$ states.Comment: 3 figures, 5 page

Geotourism potential and challenges in the Archipelago of San Andrés, Providencia, and Santa Catalina (Colombia)

The Archipelago of San Andrés, Provi­dencia, and Santa Catalina (Colombia) is a well-established tourist destination with numerous geosites that show a marvelous natural and cultural heritage of great impor­tance and attractive for the development of geotourism. Although this region is visited mainly for its spectacular coastal landscape, until now, there was a lack of geological information and interpretation about those emblematic geosites. Therefore, it is very important to develop a geoconservation strategy by promoting sustainable geo­tourism through improving the knowledge of the geological elements of this region. The landscape value of this region must be globally recognized to improve and protect its heritage resources through geotourism and geoeducation with geoconservation purposes, so that it motivates an efficient management that describes guidelines that promote the development of an appropiate tourist infrastructure, centers of scientific and cultural interpretation, dissemination and educational materials, active exchange with geoparks, continuous improvement and participation of the local communities.El archipiélago de San Andrés, Providencia y Santa Catalina (Colombia) es un des­tino turístico consolidado con numerosos geositios que muestran un maravilloso patrimonio natural y cultural de gran importancia y atractivo para el desarrollo del geotu­rismo. Si bien esta región es visitada principalmente por su espectacular paisaje costero, hasta ahora faltaba información e interpretación geológica sobre estos emblemáticos geositios. Por lo tanto, es muy importante desarrollar una estrategia de geoconservación que promueva el geoturismo sostenible por medio de la mejora del conocimiento de los elementos geológicos de esta región. El valor paisajístico de esta región debe ser recono­cido a nivel mundial para mejorar y proteger sus recursos patrimoniales por medio del geoturismo y la geoeducación con fines de geoconservación, de manera que se motive una gestión eficiente que describa lineamientos que promuevan el desarrollo de una adecuada infraestructura turística, centros de interpretación científica y cultural, materiales de difusión y educativos, intercambio activo con geoparques, mejora continua y participación de las comunidades locales

Vibrational dynamics of CO on Pd(111) in and out of thermal equilibrium

Using many-body perturbation theory and density functional perturbation theory, we study the vibrational spectra of the internal stretch (IS) mode of CO on Pd(111) for the bridge and hollow adsorption structures that are experimentally identified at 0.5~ML coverage. Our theoretical treatment allows us to determine the temperature dependence of the IS vibrational spectra under thermal conditions as well as the time evolution of the non-equilibrium transient spectra induced by femtosecond laser pulses. Under thermal conditions (i.e., for equal electronic $T_e$ and phononic $T_l$ temperatures), the calculated lifetimes at 10-150~K are mostly due to nonadiabatic couplings (NC), i.e., first-order electronic excitations. As temperature increases, also the contribution of the second-order electron mediated phonon-phonon couplings (EMPPC) progressively increases from 25\% at low temperatures to 50\% at 300~K. Our calculations for the laser-induced non-equilibrium conditions comprise experimental absorbed fluences of 6-130~J/m$^2$. For fluences for which $T_e>$2000~K, the transient vibrational spectra are characterized by two different regimes that follow the distinct time-evolution of $T_e$ and $T_l$ and are respectively dominated by NC and EMPPC processes. At lower fluences, the initial fast regime becomes progressively negligible as $T_e$ decreases and only the steady second regime remains visible. Qualitatively, all these spectral properties are common to the both adsorption structures studied here.Comment: 16 pages, 10 figures, 3 table

Modelamiento bidimensional de flujos hiperconcentrados para la elaboración del mapa de amenaza en la quebrada Bello Horizonte (La Portada) – Laredo – Trujillo – La Libertad

La presente tesis tiene como objetivo, realizar el modelamiento bidimensional de flujos hiperconcentrados haciendo uso del modelo numérico FLO 2D en el cauce de la quebrada Bello Horizonte – (La Portada), ubicado en Laredo, Trujillo, Perú. Para la elaboración del mapa de amenaza, que nos permita establecer medidas de prevención, mitigación y protección al centro poblado Bello Horizonte y sus alrededores durante la presencia de huaycos. Para ello, tuvimos que establecer una red geodésica horizontal de precisión (georreferenciación) en la zona de estudio, para poder realizar los estudios de fotogrametría, la cual nos permitió obtener y representar la superficie del terreno, se realizaron también los estudios de geotecnia e hidrología. El modelamiento hidráulico se realizó mediante el modelo numérico FLO 2D, se procedió a modelar y verificar con el evento ocurrido el 17 de marzo de 2017 y para diferentes peridos de retorno. Se procedió a evaluar y proponer las posibles soluciones, las cuales fueron el dique de enrocado para encauzamiento de huaycos y un puente en la intersección del cauce principal de la quebrada y la carretera industrial a la altura del 21+800 de la carretera PE-10A que une Trujillo – Huamachuco en el distrito de Laredo - provincia de Trujillo– departamento de La Libertad. Con el presente trabajo se busca contribuir en el estudio de los flujos hiperconcentrados en nuestro país, se tenga en cuenta este material para que la UNIVERSIDAD PRIVADA ANTENOR ORREGO, considere algunos aspectos importantes en el proceso de enseñanza-aprendizaje del estudiante de la carrera de ingeniería civil.The objective of this thesis is to carry out the two-dimensional modeling of hyper-concentrated flows using the FLO 2D numerical model in the channel of the Bello Horizonte - (La Portada) stream, located in Laredo, Trujillo, Peru. For the preparation of the threat map, which allows us to establish prevention, mitigation and protection measures for the Bello Horizonte population center and its surroundings during the presence of huaycos. For this, we had to establish a precision horizontal geodetic network (georeferencing) in the study area, in order to carry out the photogrammetry studies, which allowed us to obtain and represent the surface of the terrain, the geotechnical and hydrology studies were also carried out. The hydraulic modeling was carried out using the FLO 2D numerical model, we proceeded to model and verify with the event that occurred on March 17, 2017 and for different return periods. We proceeded to evaluate and propose possible solutions, which were the rock dam for channeling huaycos and a bridge at the intersection of the main channel of the ravine and the industrial highway at the height of 21 + 800 of the PE-10A highway. that connects Trujillo - Huamachuco in the district of Laredo - province of Trujillo - department of La Libertad. This paper seeks to contribute to the study of hyper-concentrated flows in our country, this material is taken into account so that the ANTENOR ORREGO PRIVATE UNIVERSITY, considers some important aspects in the teachinglearning process of the engineering career student civil.Tesi

Subsurface stratigraphy of the cretaceous-neogene sedimentary sequence of Manaus and Itacoatiara regions, Central Amazon

O arcabouço estratigráfico pós-paleozoico da região de Manaus e Itacoatiara (Amazônia Central) foi elaborado com base em quatro seções geológicas contendo principalmente dados geofísicos e litológicos de 15 poços tubulares com até 300 m de profundidade, complementado com descrições de afloramentos. A definição de padrões específicos das curvas de raios gama natural (RG) e resistividade (RE) permitiu a individualização das unidades sedimentares inferior, intermediária e superior e seus contatos (descontinuidades S1 e S2). A unidade inferior, definida a partir da cota de -130 m, é constituída principalmente de folhelho, cujas repetições diagráficas das curvas de RG e RE caracterizam os padrões de curva tipos funil e serrilhado. A unidade intermediária, definida nas cotas entre 20 a -180 m, é constituída por intercalações de arenitos, pelitos e conglomerados, que geram repetições cíclicas de valores das diagrafias de RG e RE, gerando os padrões serrilhado e sino. A unidade superior, definida na cota de -30 m até a superfície do terreno, é constituída principalmente de arenitos com intercalações restritas de pelitos, que definem os padrões simétrico (curva de RG) e caixote (curvas de RE e RG). O posicionamento estratigráfico das unidades inferior, intermediária e superior nas seções, bem como o aspecto litológico e as relações com as superfícies limitantes, aliado a dados estratigráficos e geocronológicos regionais permitiram sua respectiva associação com as formações Nova Olinda-Andirá (Paleozoico), Alter do Chão (Cretáceo) e Novo Remanso (Neógeno) da Bacia do Amazonas. Em função da densa cobertura de vegetação e solo, os aspectos litológicos e padrões diagráficos descritos para cada unidade podem servir de base para o estudo da cobertura sedimentar pós-paleozoicas da AmazôniaThe post-Paleozoic stratigraphic setting of Manaus and Itacoatiara area (central Amazonia) was developed based on four coross-sections containing geophysical and lithological data from 15 wells, up to 300 m deep, and outcrop description. Gamma ray (GR) and electric resistivity (ER) patterns allowed the separation into lower, intermediate and upper sedimentary units, and their contacts (S1 and S2 surfaces). The lower unit, starting at -130 m, is composed by carbonatic shale, with characteristic funnel and serrated GR and ER patterns. The intermediary unit occurs between 20 and -180 m, and is composed by sandstones with intercalated silt and claystone, with scattered layers of conglomerate. These intercalations generate cyclic repetitions of GR and ER values, creating a serrated and bell-type patterns. The upper unit occurs from -30 m to the surface and is composed by sandstone with scattered silt- and claystone, generating symmetrical (GR) and box-type (ER and GR) patterns. The stratigraphic position, lithological composition and the contact surfaces of the lower, intermediate and upper units allow us to associate them with the Nova Olinda-Andirá (Paleozoic), Alter do Chão (Cretaceous), and Novo Remanso (Neogene) formations of the Amazon Sedimentary Basin. Weathering and vegetation are always a challenge for geologic mapping the Amazon. Thus, the geophysical patterns and lithological aspects described in this paper may well serve as a good starting point for determining post-Paleozoic formations and their contact surfaces in the Amazon Sedimentary Basi

Exploiting secondary raw materials from extractive waste facilities: A case study

In recent years, resource scarcity has emphasised a need to transition from a linear to a circular flow of resources. Securing supplies of critical and secondary raw materials (CRM/SRM) for the manufacturing industry is at the forefront of industrial challenges, especially in Europe, USA and Asia. A key step towards achieving resource efficiency, is to recover these materials from anthropogenic waste deposits, such as urban landfill sites and extractive waste facilities. This means breaking away from the traditional linear use of resources to a closed-loop approach that allows maximum recovery of resources from waste. The management of extractive waste deposits and resource recovery is closely linked to the concept of urban mining. In this paper, we present a case study illustrating the feasibility of recovering SRM from EW facilities and discuss the pros and cons of undertaking such activities

Landfill mining from extractive waste facilities: The importance of a correct site characterisation and evaluation of the potentialities. A case study from Italy

Raw materials (RM) and critical raw materials (CRM; EC, 2017) supply is essential to both the maintenance and development of the EU economy as its industries rely on a steady RM supply. Thus, securing a sustainable RM and CRM supply and their circular use in the economy is of importance at EU level and beyond (Blengini et al., 2017, Coulomb et al., 2015, Vidal-Legaz et al., 2016). Furthermore, the developments of clean technologies coupled with economic growth exacerbate the short and long-term demand and needs (Blagoeva et al., 2016, Pavel and Tzimas, 2016). For example, Habib and Wenzel (2014) reported that the necessary supply Nd and Dy will grow from 10.0 Gg to 54.5 Gg and 0.5 Gg to 4.95 Gg respectively from 2010 to 2050