Rietveld Quantitative Phase Analysis of Oil Well Cement: in Situ Hydration Study at 150 Bars and 150 °C

Oil and gas well cements are multimineral materials that hydrate under high pressure and temperature. Their overall reactivity at early ages is studied by a number of techniques including through the use of the consistometer. However, for a proper understanding of the performance of these cements in the field, the reactivity of every component, in real‐world conditions, must be analysed. To date, in situ high energy synchrotron powder diffraction studies of hydrating oil well cement pastes have been carried out, but the quality of the data was not appropriated for Rietveld quantitative phase analyses. Therefore, the phase reactivities were followed by the inspection of the evolution of non‐overlapped diffraction peaks. Very recently, we have developed a new cell specially designed to rotate under high pressure and temperature. Here, this spinning capillary cell is used for in situ studies of the hydration of a commercial oil well cement paste at 150 bars and 150 °C. The powder diffraction data were analysed by the Rietveld method to quantitatively determine the reactivities of each component phase. The reaction degree of alite was 90% after 7 hours, and that of belite was 42% at 14 hours. These analyses are accurate, as the in situ measured crystalline portlandite content at the end of the experiment, 12.9 wt%, compares relatively well with the value determined ex situ by thermal analysis, i.e., 14.0 wt%. The crystalline calcium silicates forming at 150 bars and 150 °C are also discussed.This research was funded by Spanish MINECO, grant number BIA2017‐82391‐R which is co‐funded by FEDER. We thank Marc Malfois for his help during the experiment performed at NCD‐SWEET beamline at ALBA synchrotron. We also thank Marcus Paul (Dyckerhoff GmbH) for providing the OWC sample with its characterization and helpful discussions

Defesa e Segurança no Mediterrâneo

A presente investigação teve por objecto a Segurança e Defesa no Mediterrâneo, procurando responder à pergunta: a que se deve a perda de influência da EU no Mediterrâneo? Analisámos três factores que consideramos responderem à questão: 1) as falhas das sucessivas parcerias que na sua larga maioria não alteraram as condições sociais, políticas e económicas da região; 2) a ausência de uma política de defesa comum, que impossibilita a EU de se afirmar como uma grande potência e seguir uma estratégia em conformidade com os seus interesses globais e regionais; 3) a inacção numa primeira fase das Primaveras árabes com ênfase na Líbia. Todos estes factores culminaram numa abertura à influência de outras potências na região Mediterrânica.This research was focused on Security and Defense in the Mediterranean, seeking to answer the question: what is the reason for the loss of EU influence in the Mediterranean? We have analyzed three factors that we believe answer the question: 1) the failures of successive partnerships that have not changed the social, political and economic conditions in the region; 2) the absence of a common defense policy, which makes it impossible for the EU to assert itself as a major power and follow a strategy in line with its global and regional interests; 3) the inaction in the first phase of the Arab Springs with emphasis on Libya. All these factors culminated in an opening to the influence of other powers in the Mediterranean region

Notes and contributions to the knowledge of the flora of Minorca (VIII)

Abstract not availabl

Notes and contributions to the knowledge of the flora of Menorca

Abstract not availabl

Phylogeography of western Mediterranean Cymbalaria (Plantaginaceae) reveals two independent long-distance dispersals and entails new taxonomic circumscriptions

The Balearic Islands, Corsica and Sardinia (BCS) constitute biodiversity hotspots in the western Mediterranean Basin. Oligocene connections and long distance dispersal events have been suggested to cause presence of BCS shared endemic species. One of them is Cymbalaria aequitriloba, which, together with three additional species, constitute a polyploid clade endemic to BCS. Combining amplified fragment length polymorphism (AFLP) fingerprinting, plastid DNA sequences and morphometrics, we inferred the phylogeography of the group and evaluated the species' current taxonomic circumscriptions. Based on morphometric and AFLP data we propose a new circumscription for C. fragilis to additionally comprise a group of populations with intermediate morphological characters previously included in C. aequitriloba. Consequently, we suggest to change the IUCN category of C. fragilis from critically endangered (CR) to near threatened (NT). Both morphology and AFLP data support the current taxonomy of the single island endemics C. hepaticifolia and C. muelleri. The four species had a common origin in Corsica-Sardinia, and two long-distance dispersal events to the Balearic Islands were inferred. Finally, plastid DNA data suggest that interspecific gene flow took place where two species co-occur

Terephthalic acid synthesis at higher concentrations in high-temperature liquid water. 2. Eliminating undesired byproducts

We synthesized terephthalic acid (TPA) from p -xylene at an initial concentration above its solubility limit in high-temperature liquid water (HTW). The nominal p -xylene loading at the reaction conditions was 0.4 mol L −1 , which is the highest reported to date for generation of high TPA yields (>70 mol %) in HTW. The presence of two liquid phases during the reaction did not appear to accelerate the rate, unlike behavior reported for some other organic reactions done “on water” at lower temperatures. Adding oxygen gas in a large increment during synthesis produced a black liquid and a black solid byproduct, which is a previously undocumented problem. Adding oxygen in smaller increments prevented formation of the liquid and solid byproducts and also provided high selectivities (90 mol %) and yields (>70 mol %) of TPA. These results demonstrate the feasibility of HTW as a medium for TPA synthesis at p -xylene concentrations even higher than its solubility limit. © 2009 American Institute of Chemical Engineers AIChE J, 2009Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/63001/1/11761_ftp.pd

Challenges for future food systems: from the Green Revolution to food supply chains with a special focus on sustainability

Finding a food system to feed the growing worldwide population remains a challenge, especially in the current era, where natural resources are being dramatically depleted. From a historical point of view, the Green Revolution, together with biofortification and sustainable intensification, was established as a possible solution to counter hunger and malnutrition during the second half of the 20th century. As a solution, to overcome the limitations attributed to the Green Revolution, food supply chains were developed. The current food system, based on the long food supply chain (LFSC), is characterized by globalization, promoting several advantages for both producers and consumers. However, LFSC has been demonstrated to be unable to feed the global population and, furthermore, it generates negative ecological, environmental, logistical, and nutritional pressures. Thus, novel efficient food systems are required to respond to current environmental and consumers' demands, as is the case of short food supply chain (SFSC). As a recently emerging food system, the evaluation of SFSC sustainability in terms of environmental, economic, and social assessment is yet to be determined. This review is focused on the evolution of food supply systems, starting from the Green Revolution to food supply chains, providing a significant perspective on sustainability.The research leading to these results was supported by MICINN supporting the Ramón y Cajal grant for M. A. Prieto (RYC-2017-22891), the Juan de la Cierva Incorporación for Hui Cao (IJC2020-04605- 5-I) and the FPU grant for A. Soria-Lopez (FPU2020/06140); by Xunta de Galicia for supporting the program (EXCELENCIA-ED431F 2020/12) and by supporting the postdoctoral grant of M. Fraga- Corral (ED481B-2019-096) and the predoctoral grants of M. Carpena (ED481A 2021/313) and of P. Garcia-Oliveira (ED481A-2019/295); and by the European Union through the “NextGenerationEU” program supporting the “Margarita Salas” grant awarded to P. Garcia-Perez. The authors are grateful to Ibero-American Program on Science and Technology (CYTED—AQUA-CIBUS, P317RT0003), to the Bio Based Industries Joint Undertaking (JU) under grant agreement No. 888003 UP4HEALTH Project (H2020-BBI-JTI-2019) that supports the work of P. Otero and P. Garcia-Perez. The JU receives support from the European Union’s Horizon 2020 research and innovation program and the Bio Based Industries Consortium. The project SYSTEMIC Knowledge hub on Nutrition and Food Security, has received funding from national research funding parties in Belgium (FWO), France (INRA), Germany (BLE), Italy (MIPAAF), Latvia (IZM), Norway (RCN), Portugal (FCT), and Spain (AEI) in a joint action of JPI HDHL, JPI-OCEANS and FACCE-JPI launched in 2019 under the ERA-NET ERA-HDHL (No. 696295)