scholarly journals Coastal HF radars in the Mediterranean: status of operations and a framework for future development

2021 ◽  
Author(s):  
Pablo Lorente ◽  
Eva Aguiar ◽  
Michele Bendoni ◽  
Maristella Berta ◽  
Carlo Brandini ◽  
...  

Abstract. Due to the semi-enclosed nature of the Mediterranean Sea, natural disasters and anthropogenic activities impose stronger pressures on its coastal ecosystems than in any other sea of the world. With the aim of responding adequately to science priorities and societal challenges, littoral waters must be effectively monitored with High-Frequency radar (HFR) systems. This land-based remote sensing technology can provide, in near real-time, fine-resolution maps of the surface circulation over broad coastal areas, along with reliable directional wave and wind information. The main goal of this work is to showcase the current status of the Mediterranean HFR network and the future roadmap for orchestrated actions. Ongoing collaborative efforts and recent progress of this regional alliance are not only described but also connected with other European initiatives and global frameworks, highlighting the advantages of this cost-effective instrument for the multi-parameter monitoring of the sea state. Coordinated endeavours between HFR operators from different multi-disciplinary institutions are mandatory to reach a mature stage at both national and regional levels, striving to: i) harmonize deployment and maintenance practices; ii) standardize data, metadata and quality control procedures; iii) centralize data management, visualization and access platforms; iv) develop practical applications of societal benefit, that can be used for strategic planning and informed decision-making in the Mediterranean marine environment. Such fit-for-purpose applications can serve for search and rescue operations, safe vessel navigation, tracking of marine pollutants, the monitoring of extreme events or the investigation of transport processes and the connectivity between offshore waters and coastal ecosystems. Finally, future prospects within the Mediterranean framework are discussed along with a wealth of socio-economic, technical and scientific challenges to be faced during the implementation of this integrated HFR regional network.

2021 ◽  
Vol 13 (15) ◽  
pp. 8421
Author(s):  
Yuan Gao ◽  
Jiandong Huang ◽  
Meng Li ◽  
Zhongran Dai ◽  
Rongli Jiang ◽  
...  

Uranium mining waste causes serious radiation-related health and environmental problems. This has encouraged efforts toward U(VI) removal with low cost and high efficiency. Typical uranium adsorbents, such as polymers, geopolymers, zeolites, and MOFs, and their associated high costs limit their practical applications. In this regard, this work found that the natural combusted coal gangue (CCG) could be a potential precursor of cheap sorbents to eliminate U(VI). The removal efficiency was modulated by chemical activation under acid and alkaline conditions, obtaining HCG (CCG activated with HCl) and KCG (CCG activated with KOH), respectively. The detailed structural analysis uncovered that those natural mineral substances, including quartz and kaolinite, were the main components in CCG and HCG. One of the key findings was that kalsilite formed in KCG under a mild synthetic condition can conspicuous enhance the affinity towards U(VI). The best equilibrium adsorption capacity with KCG was observed to be 140 mg/g under pH 6 within 120 min, following a pseudo-second-order kinetic model. To understand the improved adsorption performance, an adsorption mechanism was proposed by evaluating the pH of uranyl solutions, adsorbent dosage, as well as contact time. Combining with the structural analysis, this revealed that the uranyl adsorption process was mainly governed by chemisorption. This study gave rise to a utilization approach for CCG to obtain cost-effective adsorbents and paved a novel way towards eliminating uranium by a waste control by waste strategy.


Author(s):  
J. Selva ◽  
A. Amato ◽  
A. Armigliato ◽  
R. Basili ◽  
F. Bernardi ◽  
...  

AbstractDestructive tsunamis are most often generated by large earthquakes occurring at subduction interfaces, but also other “atypical” sources—defined as crustal earthquakes and non-seismic sources altogether—may cause significant tsunami threats. Tsunamis may indeed be generated by different sources, such as earthquakes, submarine or coastal landslides, volcano-related phenomena, and atmospheric perturbations. The consideration of atypical sources is important worldwide, but it is especially prominent in complex tectonic settings such as the Mediterranean, the Caribbean, or the Indonesian archipelago. The recent disasters in Indonesia in 2018, caused by the Palu-Sulawesi magnitude Mw 7.5 crustal earthquake and by the collapse of the Anak-Krakatau volcano, recall the importance of such sources. Dealing with atypical sources represents a scientific, technical, and computational challenge, which depends on the capability of quantifying and managing uncertainty efficiently and of reducing it with accurate physical modelling. Here, we first introduce the general framework in which tsunami threats are treated, and then we review the current status and the expected future development of tsunami hazard quantifications and of the tsunami warning systems in Italy, with a specific focus on the treatment of atypical sources. In Italy, where the memory of historical atypical events like the 1908 Messina earthquake or the relatively recent 2002 Stromboli tsunami is still vivid, specific attention has been indeed dedicated to the progressive development of innovative strategies to deal with such atypical sources. More specifically, we review the (national) hazard analyses and their application for coastal planning, as well as the two operating tsunami warning systems: the national warning system for seismically generated tsunamis (SiAM), whose upstream component—the CAT-INGV—is also a Tsunami Service Provider of the North-eastern Atlantic, the Mediterranean and connected seas Tsunami Warning System (NEAMTWS) coordinated by the Intergovernmental Coordination Group established by the Intergovernmental Oceanographic Commission (IOC) of UNESCO, and the local warning system for tsunamis generated by volcanic slides along the Sciara del Fuoco of Stromboli volcano. Finally, we review the state of knowledge about other potential tsunami sources that may generate significant tsunamis for the Italian coasts, but that are not presently considered in existing tsunami warning systems. This may be considered the first step towards their inclusion in the national tsunami hazard and warning programs.


Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1827
Author(s):  
Mengyao Li ◽  
Yu Zhang ◽  
Ting Zhang ◽  
Yong Zuo ◽  
Ke Xiao ◽  
...  

The cost-effective conversion of low-grade heat into electricity using thermoelectric devices requires developing alternative materials and material processing technologies able to reduce the currently high device manufacturing costs. In this direction, thermoelectric materials that do not rely on rare or toxic elements such as tellurium or lead need to be produced using high-throughput technologies not involving high temperatures and long processes. Bi2Se3 is an obvious possible Te-free alternative to Bi2Te3 for ambient temperature thermoelectric applications, but its performance is still low for practical applications, and additional efforts toward finding proper dopants are required. Here, we report a scalable method to produce Bi2Se3 nanosheets at low synthesis temperatures. We studied the influence of different dopants on the thermoelectric properties of this material. Among the elements tested, we demonstrated that Sn doping resulted in the best performance. Sn incorporation resulted in a significant improvement to the Bi2Se3 Seebeck coefficient and a reduction in the thermal conductivity in the direction of the hot-press axis, resulting in an overall 60% improvement in the thermoelectric figure of merit of Bi2Se3.


Plants ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1461
Author(s):  
Roberto Braglia ◽  
Lorenza Rugnini ◽  
Sara Malizia ◽  
Francesco Scuderi ◽  
Enrico Luigi Redi ◽  
...  

Increasing levels of freshwater contaminants, mainly due to anthropogenic activities, have resulted in a great deal of interest in finding new eco-friendly, cost-effective and efficient methods for remediating polluted waters. The aim of this work was to assess the feasibility of using a green microalga Desmodesmus sp., a cyanobacterium Nostoc sp. and a hemicryptophyte Ampelodesmos mauritanicus to bioremediate a water polluted with an excess of nutrients (nitrogen and phosphorus) and heavy metals (copper and nickel). We immediately determined that Nostoc sp. was sensitive to metal toxicity, and thus Desmodesmus sp. was chosen for sequential tests with A. mauritanicus. First, A. mauritanicus plants were grown in the ‘polluted’ culture medium for seven days and were, then, substituted by Desmodesmus sp. for a further seven days (14 days in total). Heavy metals were shown to negatively affect both the growth rates and nutrient removal capacity. The sequential approach resulted in high metal removal rates in the single metal solutions up to 74% for Cu and 85% for Ni, while, in the bi-metal solutions, the removal rates were lower and showed a bias for Cu uptake. Single species controls showed better outcomes; however, further studies are necessary to investigate the behavior of new species.


Nukleonika ◽  
2016 ◽  
Vol 61 (2) ◽  
pp. 207-212 ◽  
Author(s):  
Irina V. Litovko ◽  
Alexy A. Goncharov ◽  
Andrew N. Dobrovolskiy ◽  
Lily V. Naiko ◽  
Irina V. Naiko

Abstract The paper presents new generation plasma optical devices based on the electrostatic plasma lens configuration that opens a novel attractive possibility for effective high-tech practical applications. Original approaches to use of plasma accelerators with closed electron drift and open walls for the creation of a cost-effective low-maintenance plasma lens with positive space charge and possible application for low-cost, low-energy rocket engine are described. The preliminary experimental, theoretical and simulation results are presented. It is noted that the presented plasma devices are attractive for many different applications in the state-of-the-art vacuum-plasma processing.


Polymers ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 1393 ◽  
Author(s):  
Jie Cao ◽  
Jianbei Zhang ◽  
Yuejun Zhu ◽  
Shanshan Wang ◽  
Xiujun Wang ◽  
...  

The pollution of water resources has become a worldwide concern. The primary pollutants including insoluble oil, toxic dyes, and heavy metal ions. Herein, we report a polymer adsorbent, named SPCT, to remove the above three contaminants from water simultaneously. The preparation process of SPCT contains two steps. Firstly, a hydrogel composed of sulfonated phenolic resin (SMP) and polyethyleneimine (PEI) was synthesized using glutaraldehyde (GA) as the crosslinking agent, and the product was named SPG. Then SPCT was prepared by the reaction between SPG and citric acid (CA) at 170 ∘ C. SPCT exhibited an excellent performance for the removal of methylene blue (MB) and Cu(II) from aqueous solution. For a solution with a pollutant concentration of 50 mg L−1, a removal efficiency of above 90% could be obtained with a SPCT dosage of 0.2 g L−1 for MB, or a SPCT dosage of 0.5 g L−1 for Cu(II), respectively. SPCT also presented an interesting wettability. In air, it was both superhydrophilic and superoleophilic, and it was superoleophobic underwater. Therefore, SPCT could successfully separate oil-in-water emulsion with high separation efficiency and resistance to oil fouling. Additionally, SPCT was easily regenerated by using dilute HCl solution as an eluent. The outstanding performance of SPCT and the efficient, cost-effective preparation process highlight its potential for practical applications.


2021 ◽  
Vol 65 (3) ◽  
pp. 42-51
Author(s):  
N. Pyzhikov ◽  
E. Gushchin

The article analyses the current status of the Belt and Road Initiative (BRI), its key achievements and challenges, including those related to the COVID 19 pandemic. In the 2010s China has become one of world’s largest investors and BRI is one of the most important tools of Chinese investment policy. Due to its flexible structure, BRI has been able to adjust and develop in the context of the U.S. – China trade war and the growing anti-Chinese sentiment in the world that included the concerns over so called China’s debt diplomacy. But this lack of rigidity is also a challenge to those who study BRI because there is no official list of projects (estimations vary between 118 and 374) and countries participating in BRI (up to 138). China’s key BRI partner is Pakistan. The total value of projects implemented by China in Pakistan as part of the China-Pakistan Economic Corridor was initially estimated at $46 billion but now exceeds $70 billion (new projects were signed even during the pandemic). BRI is increasing the number of its participants. In March 2019 Italy became the first G7 country to sign a BRI MoU with China. While implementing BRI China has faced such challenges as rising concerns of “China’s debt trap”, as well as ecological and political issues. In 2020 BRI is facing a new challenge with the COVID-19 pandemic. Some BRI projects were postponed because of the pandemic, but in some cases they were unaffected. There are 64 out of 138 countries participating in BRI that come from low and lower-middle income groups according to the World Bank classification. Their average ratio of foreign debt to GDP was 54% in 2018–2019. It is most likely that these countries will be hit hard by the coronacrisis. Thus the pandemic will encourage China to tighten the selection process for BRI projects with a focus on the most strategically important and cost effective ones. From the point of view of China’s BRI partners, the effect can be two-fold: the most unstable economies will increase their dependence on China, while with the economically strong countries China will be more willing to make concessions and offer more favorable conditions for cooperation.


2021 ◽  
Vol 12 (5) ◽  
pp. 6557-6579

The introduction of inorganic and organic pollutants into water bodies has become a serious issue globally. The waste streams released from the textile, plastic, leather, paper, pharmaceutical, and food industries introduce different natural and synthetic dyes into the aquatic system. Nanomaterials play a significant role in the photocatalytic degradation of dyes present in wastewater. Inorganic metal oxide nanoparticles have many improved physical and chemical properties and attracted much attention in photocatalytic activities. Dyes have been released in our aquatic bodies due to many anthropogenic activities and caused life-threatening problems. Various conventional methods were reported to remove dyes from water and wastewater; the photocatalytic method is one of the efficient and cost-effective. The present review article includes detailed information on photocatalysis, the potential of metal oxide and their composite materials as photocatalysts in the degradation of toxic dyes, and some common synthetic and characterization methods used for metal oxide-based nanoparticles.


Anemia ◽  
2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Adriana Ceci ◽  
Laura Mangiarini ◽  
Mariagrazia Felisi ◽  
Franco Bartoloni ◽  
Angela Ciancio ◽  
...  

Thalassaemia and other haemoglobinopathies constitute an important health problem in Mediterranean countries, placing a tremendous emotional, psychological, and economic burden on their National Health systems. The development of new chelators in the most recent years had a major impact on the treatment of thalassaemia and on the quality of life of thalassaemic patients. A new initiative was promoted by the Italian Ministry of Health, establishing a Registry for thalassaemic patients to serve as a tool for the development of cost-effective diagnostic and therapeutic approaches and for the definition of guidelines supporting the most appropriate management of the iron-chelating therapy and a correct use of the available iron-chelating agents. This study represents the analysis of the preliminary data collected for the evaluation of current status of the iron chelation practice in the Italian thalassaemic population and describes how therapeutic interventions can widely differ in the different patients' age groups.


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