The Regional Advisory Councils: what is their potential to incorporate stakeholder knowledge into fisheries governance?

PubMed

Linke, Sebastian; Dreyer, Marion; Sellke, Piet

2011-03-01

The protection of the Baltic Sea ecosystem is exacerbated by the social, environmental and economic complexities of governing European fisheries. Increased stakeholder participation and knowledge integration are suggested to improve the EU's Common Fisheries Policy (CFP), suffering from legitimacy, credibility and compliance problems. As a result, the CFP was revised in 2002 to involve fisheries representatives, NGOs and other stakeholders through so called Regional Advisory Councils (RACs) in the policy process. We address the RAC's task to incorporate stakeholder knowledge into the EU's fisheries governance system in empirical and theoretical perspectives. Drawing on a four-stage governance concept we subsequently suggest that a basic problem is a mismatch between participation purpose (knowledge inclusion) and the governance stage at which RACs are formally positioned (evaluation of management proposals). We conclude that, if the aim is to broaden the knowledge base of fisheries management, stakeholders need to be included earlier in the governance process.

Best of enemies: Using social network analysis to explore a policy network in European smoke-free policy.

PubMed

Weishaar, Heide; Amos, Amanda; Collin, Jeff

2015-05-01

Networks and coalitions of stakeholders play a crucial role in the development and implementation of policies, with previous research highlighting that networks in tobacco control are characterised by an antagonism between supporters and opponents of comprehensive tobacco control policies. This UK-based study used quantitative and qualitative network analysis (drawing on 176 policy submissions and 32 interviews) to systematically map and analyse a network of actors involved in the development of European Union (EU) smoke-free policy. Policy debates were dominated by two coalitions of stakeholders with starkly opposing positions on the issue. One coalition, consisting primarily of health-related organisations, supported comprehensive EU smoke-free policy, whereas the other, led by tobacco manufacturers' organisations, opposed the policy initiative. The data suggest that, aided by strong political commitment of EU decision makers to develop smoke-free policy, advocates supporting comprehensive EU policy were able to frame policy debates in ways which challenged the tobacco industry's legitimacy. They then benefited from the stark polarisation between the two coalitions. The paper provides empirical evidence of the division between two distinct coalitions in tobacco policy debates and draws attention to the complex processes of consensus-seeking, alliance-building and strategic action which are integral to the development of EU policy. Highlighting network polarisation and industry isolation as factors which seemed to increase tobacco control success, the study demonstrates the potential significance and value of FCTC article 5.3 for tobacco control policy-making. Copyright © 2015 Elsevier Ltd. All rights reserved.

Implications of the accession of the Republic of Croatia to the European Union for Croatian health care system.

PubMed

Ostojić, Rajko; Bilas, Vlatka; Franc, Sanja

2012-09-01

The Republic of Croatia's accession to the European Union (EU) will affect all segments of economy and society, including the health care system. The aim of this paper is to establish the potential effects of joining the EU on Croatian health care, as well as to assess its readiness to enter this regional economic integration. The paper identifies potential areas of impact of EU accession on Croatian health care and analyzes the results of the conducted empirical research. In this research, a method of in-depth interviews was applied on a sample of 49 subjects; health professionals from public and private sectors, health insurance companies, pharmaceutical companies, drug wholesalers, and non-governmental organisations (patient associations). Once Croatia joins the EU, it will face: new rules and priorities in line with the current European health strategy; the possibilities of drawing funds from European cohesion funds; labour migrations; new guidelines on patient safety and mobility. From the aspect of harmonising national regulations with EU regulations in the area of health care, Croatian system can be assessed as ready to enter the EU. Croatia's accession to the EU can result in a better information flow, growth of competitiveness of Croatian health care system, enhanced quality, inflow of EU funds, development of health tourism, but also in increased migration of health care professionals, and potential increase in the cost of health care services. Functioning within the EU framework might result in adaptation to the EU standards, but it could also result in the concentration of staff and institutions in larger cities.

Data Extraction and Management in Networks of Observational Health Care Databases for Scientific Research: A Comparison of EU-ADR, OMOP, Mini-Sentinel and MATRICE Strategies

PubMed Central

Gini, Rosa; Schuemie, Martijn; Brown, Jeffrey; Ryan, Patrick; Vacchi, Edoardo; Coppola, Massimo; Cazzola, Walter; Coloma, Preciosa; Berni, Roberto; Diallo, Gayo; Oliveira, José Luis; Avillach, Paul; Trifirò, Gianluca; Rijnbeek, Peter; Bellentani, Mariadonata; van Der Lei, Johan; Klazinga, Niek; Sturkenboom, Miriam

2016-01-01

Introduction: We see increased use of existing observational data in order to achieve fast and transparent production of empirical evidence in health care research. Multiple databases are often used to increase power, to assess rare exposures or outcomes, or to study diverse populations. For privacy and sociological reasons, original data on individual subjects can’t be shared, requiring a distributed network approach where data processing is performed prior to data sharing. Case Descriptions and Variation Among Sites: We created a conceptual framework distinguishing three steps in local data processing: (1) data reorganization into a data structure common across the network; (2) derivation of study variables not present in original data; and (3) application of study design to transform longitudinal data into aggregated data sets for statistical analysis. We applied this framework to four case studies to identify similarities and differences in the United States and Europe: Exploring and Understanding Adverse Drug Reactions by Integrative Mining of Clinical Records and Biomedical Knowledge (EU-ADR), Observational Medical Outcomes Partnership (OMOP), the Food and Drug Administration’s (FDA’s) Mini-Sentinel, and the Italian network—the Integration of Content Management Information on the Territory of Patients with Complex Diseases or with Chronic Conditions (MATRICE). Findings: National networks (OMOP, Mini-Sentinel, MATRICE) all adopted shared procedures for local data reorganization. The multinational EU-ADR network needed locally defined procedures to reorganize its heterogeneous data into a common structure. Derivation of new data elements was centrally defined in all networks but the procedure was not shared in EU-ADR. Application of study design was a common and shared procedure in all the case studies. Computer procedures were embodied in different programming languages, including SAS, R, SQL, Java, and C++. Conclusion: Using our conceptual framework we found several areas that would benefit from research to identify optimal standards for production of empirical knowledge from existing databases.an opportunity to advance evidence-based care management. In addition, formalized CM outcomes assessment methodologies will enable us to compare CM effectiveness across health delivery settings. PMID:27014709

Effect of tasting and information on consumer opinion about pig castration.

PubMed

Kallas, Zein; Gil, José Maria; Panella-Riera, Nuria; Blanch, Marta; Font-i-Furnols, Maria; Chevillon, Patrick; De Roest, Kees; Tacken, Gemma; Oliver, Maria Angels

2013-10-01

Our research explored the relative importance of pig castration amongst other aspects of animal welfare, and the potential impact of information and sensory experiences on European Union (EU) consumers' preferences. The EU is considering a future ban on surgical pig castration by 2018 which may affect markets and consumers' preferences. We carried out an empirical study using consumer-level data obtained from questionnaires completed in a controlled environment by a total of 825 consumers. The experiment was carried out in six EU countries (Spain, United Kingdom, The Netherlands, France, Italy and Germany) which account for 66.0% of the EU-27's and 76.3% of the EU-15's meat production. Results show that consumers do not perceive pig castration to be a relevant aspect of animal welfare nor its relationship with meat quality. Consumers with healthy life styles, concerned about animal welfare and who have had a negative sensory experience with boar meat are willing to accept paying more to avoid boar taint. Copyright © 2013 Elsevier Ltd. All rights reserved.

Employment Condition, Economic Deprivation and Self-Evaluated Health in Europe: Evidence from EU-SILC 2009-2012.

PubMed

Bacci, Silvia; Pigini, Claudia; Seracini, Marco; Minelli, Liliana

2017-02-03

Background : The mixed empirical evidence about employment conditions (i.e., permanent vs. temporary job, full-time vs. part-time job) as well as unemployment has motivated the development of conceptual models with the aim of assessing the pathways leading to effects of employment status on health. Alongside physically and psychologically riskier working conditions, one channel stems in the possibly severe economic deprivation faced by temporary workers. We investigate whether economic deprivation is able to partly capture the effect of employment status on Self-evaluated Health Status (SHS). Methods : Our analysis is based on the European Union Statistics on Income and Living Conditions (EU-SILC) survey, for a balanced sample from 26 countries from 2009 to 2012. We estimate a correlated random-effects logit model for the SHS that accounts for the ordered nature of the dependent variable and the longitudinal structure of the data. Results and Discussion : Material deprivation and economic strain are able to partly account for the negative effects on SHS from precarious and part-time employment as well as from unemployment that, however, exhibits a significant independent negative association with SHS. Conclusions : Some of the indicators used to proxy economic deprivation are significant predictors of SHS and their correlation with the employment condition is such that it should not be neglected in empirical analysis, when available and further to the monetary income.

Employment Condition, Economic Deprivation and Self-Evaluated Health in Europe: Evidence from EU-SILC 2009–2012

PubMed Central

Bacci, Silvia; Pigini, Claudia; Seracini, Marco; Minelli, Liliana

2017-01-01

Background: The mixed empirical evidence about employment conditions (i.e., permanent vs. temporary job, full-time vs. part-time job) as well as unemployment has motivated the development of conceptual models with the aim of assessing the pathways leading to effects of employment status on health. Alongside physically and psychologically riskier working conditions, one channel stems in the possibly severe economic deprivation faced by temporary workers. We investigate whether economic deprivation is able to partly capture the effect of employment status on Self-evaluated Health Status (SHS). Methods: Our analysis is based on the European Union Statistics on Income and Living Conditions (EU-SILC) survey, for a balanced sample from 26 countries from 2009 to 2012. We estimate a correlated random-effects logit model for the SHS that accounts for the ordered nature of the dependent variable and the longitudinal structure of the data. Results and Discussion: Material deprivation and economic strain are able to partly account for the negative effects on SHS from precarious and part-time employment as well as from unemployment that, however, exhibits a significant independent negative association with SHS. Conclusions: Some of the indicators used to proxy economic deprivation are significant predictors of SHS and their correlation with the employment condition is such that it should not be neglected in empirical analysis, when available and further to the monetary income. PMID:28165375

How Does Medical Device Regulation Perform in the United States and the European Union? A Systematic Review

PubMed Central

Kramer, Daniel B.; Xu, Shuai; Kesselheim, Aaron S.

2012-01-01

Background Policymakers and regulators in the United States (US) and the European Union (EU) are weighing reforms to their medical device approval and post-market surveillance systems. Data may be available that identify strengths and weakness of the approaches to medical device regulation in these settings. Methods and Findings We performed a systematic review to find empirical studies evaluating medical device regulation in the US or EU. We searched Medline using two nested categories that included medical devices and glossary terms attributable to the US Food and Drug Administration and the EU, following PRISMA guidelines for systematic reviews. We supplemented this search with a review of the US Government Accountability Office online database for reports on US Food and Drug Administration device regulation, consultations with local experts in the field, manual reference mining of selected articles, and Google searches using the same key terms used in the Medline search. We found studies of premarket evaluation and timing (n = 9), studies of device recalls (n = 8), and surveys of device manufacturers (n = 3). These studies provide evidence of quality problems in pre-market submissions in the US, provide conflicting views of device safety based largely on recall data, and relay perceptions of some industry leaders from self-surveys. Conclusions Few studies have quantitatively assessed medical device regulation in either the US or EU. Existing studies of US and EU device approval and post-market evaluation performance suggest that policy reforms are necessary for both systems, including improving classification of devices in the US and promoting transparency and post-market oversight in the EU. Assessment of regulatory performance in both settings is limited by lack of data on post-approval safety outcomes. Changes to these device approval and post-marketing systems must be accompanied by ongoing research to ensure that there is better assessment of what works in either setting. Please see later in the article for the Editors' Summary. PMID:22912563

A multiplicative process for generating a beta-like survival function with application to the UK 2016 EU referendum results

NASA Astrophysics Data System (ADS)

Fenner, Trevor; Kaufmann, Eric; Levene, Mark; Loizou, George

Human dynamics and sociophysics suggest statistical models that may explain and provide us with better insight into social phenomena. Contextual and selection effects tend to produce extreme values in the tails of rank-ordered distributions of both census data and district-level election outcomes. Models that account for this nonlinearity generally outperform linear models. Fitting nonlinear functions based on rank-ordering census and election data therefore improves the fit of aggregate voting models. This may help improve ecological inference, as well as election forecasting in majoritarian systems. We propose a generative multiplicative decrease model that gives rise to a rank-order distribution and facilitates the analysis of the recent UK EU referendum results. We supply empirical evidence that the beta-like survival function, which can be generated directly from our model, is a close fit to the referendum results, and also may have predictive value when covariate data are available.

Understanding the side effects of emission trading: implications for waste management.

PubMed

Braschel, Nina; Posch, Alfred; Pierer, Magdalena

2014-01-01

The trading of emission allowances is an important market instrument in climate policy. However, the inclusion of certain branches of industry in the trading system not only provides incentives for emission reduction, it also entails unwanted side effects. Thus, the objective of the present study is to identify such side effects-positive and negative-by examining the potential impact of waste management inclusion in the European Union Emissions Trading Scheme (EU ETS). Desk research was supplemented with qualitative and quantitative empirical analysis (based on expert interviews and a questionnaire) in order to analyse the related perceptions and expectations of actors and stakeholders. The impact of waste management inclusion in the EU ETS is analysed in terms of the following three areas: (i) costs and cost pass-through, (ii), competitiveness and market position, and (iii) carbon leakage. Concerning expectations in the area of costs, both the interviewed experts and the practitioners surveyed thought that costs were likely to increase or that they could be passed on to customers. However, experts and practitioners differed with respect to the possibility of carbon leakage. Clearly, increased knowledge of the possible impact arising from inclusion of the waste sector in the EU ETS would enable managers to become more proactive and to manage waste streams and treatment options more economically.

Impact of rapid methicillin-resistant Staphylococcus aureus polymerase chain reaction testing on mortality and cost effectiveness in hospitalized patients with bacteraemia: a decision model.

PubMed

Brown, Jack; Paladino, Joseph A

2010-01-01

Patients hospitalized with Staphylococcus aureus bacteraemia have an unacceptably high mortality rate. Literature available to date has shown that timely selection of the most appropriate antibacterial may reduce mortality. One tool that may help with this selection is a polymerase chain reaction (PCR) assay that distinguishes methicillin (meticillin)-resistant S. aureus (MRSA) from methicillin-susceptible S. aureus (MSSA) in less than 1 hour. To date, no information is available evaluating the impact of this PCR technique on clinical or economic outcomes. To evaluate the effect of a rapid PCR assay on mortality and economics compared with traditional empiric therapy, using a literature-derived model. A literature search for peer-reviewed European (EU) and US publications regarding treatment regimens, outcomes and costs was conducted. Information detailing the rates of infection, as well as the specificity and sensitivity of a rapid PCR assay (Xpert MRSA/SA Blood Culture PCR) were obtained from the peer-reviewed literature. Sensitivity analysis varied the prevalence rate of MRSA from 5% to 80%, while threshold analysis was applied to the cost of the PCR test. Hospital and testing resource consumption were valued with direct medical costs, adjusted to year 2009 values. Adjusted life-years were determined using US and WHO life tables. The cost-effectiveness ratio was defined as the cost per life-year saved. Incremental cost-effectiveness ratios (ICERs) were calculated to determine the additional cost necessary to produce additional effectiveness. All analyses were performed using TreeAge Software (2008). The mean mortality rates were 23% for patients receiving empiric vancomycin subsequently switched to semi-synthetic penicillin (SSP) for MSSA, 36% for patients receiving empiric vancomycin treatment for MRSA, 59% for patients receiving empiric SSP subsequently switched to vancomycin for MRSA and 12% for patients receiving empiric SSP for MSSA. Furthermore, with an MRSA prevalence of 30%, the numbers of patients needed to test in order to save one life were 14 and 16 compared with empiric vancomycin and SSP, respectively. The absolute mortality difference for MRSA prevalence rates of 80% and 5% favoured the PCR testing group at 2% and 10%, respectively, compared with empiric vancomycin and 18% and 1%, respectively, compared with empiric SSP. In the EU, the cost-effectiveness ratios for empiric vancomycin- and SSP-treated patients were Euro 695 and Euro 687 per life-year saved, respectively, compared with Euro 636 per life-year saved for rapid PCR testing. In the US, the cost-effectiveness ratio was $US 898 per life-year saved for empiric vancomycin and $US 820 per life-year saved for rapid PCR testing. ICERs demonstrated dominance of the PCR test in all instances. Threshold analysis revealed that PCR testing would be less costly overall, even at greatly inflated assay prices. Rapid PCR testing for MRSA appears to have the potential to reduce mortality rates while being less costly than empiric therapy in the EU and US, across a wide range of MRSA prevalence rates and PCR test costs.

Ownership of individual retirement accounts – an empirical analysis based on SHARE

PubMed Central

Garcia, Maria Teresa Medeiros; Marques, Pedro Deslandes Correia Vasconcelos

2017-01-01

This paper examines the household retirement saving decisions in what concerns to the ownership of Individual Retirement Accounts (IRAs) in eight European Union (EU) countries. IRAs are more and more seen as an alternative to public pension benefits, which are decreasing. Therefore, understanding the enrolment in IRAs, both the socio-economic factors and over time, is most important. Detailed empirical analysis of the factors that might influence the ownership of IRAs is presented based on Survey of Health Ageing and Retirement in Europe (SHARE), using data from Wave 2 (2006-2007) and Wave 4 (2010-2011). Further, to analyse the impact of legal retirement age in the ownership of IRAs, two subsamples are considered: people aged between 50 and 64 years old (50-64 years) and people aged 65 or over (≥ 65 years). The results suggest that age, years of education, income and ownership of dwelling influence positively and significantly household saving, while number of children, marital status and risk aversion have a negative effect. Marital status and income are not statistically significant for retired people. Policy implications are derived. PMID:28983144

Does economic, financial and institutional developments matter for environmental quality? A comparative analysis of EU and MEA countries.

PubMed

Abid, Mehdi

2017-03-01

The aim of this study is to test the hypothesis of the Environmental Kuznets Curve (EKC) with a sample of 58 MEA (Middle East & African) and 41 EU (European Union) countries for the period 1990 to 2011. The empirical analysis is carried out using the GMM-system method to solve the problem of endogenous variables. We focused on direct and indirect effects of institutional quality (through the efficiency of public expenditure, financial development, trade openness and foreign direct investment) and the income-emission relationship. We found a monotonically increasing relationship between CO 2 emissions and GDP in both MEA and EU regions. The policy implication is clear: in order to have sustainable positive economic performance and to reduce carbon dioxide emission in the country at the same time, policy makers should regulate and enhance the role and efficiency of domestic institutions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Russia-A New Empire Under Construction. The Russian Policy towards Former Communist Satellites-Mechanisms of Exertion of Influence

DTIC Science & Technology

2008-12-01

the agreement, seeking rather better cooperation within the EU than with the USA. Finally, the very last involvement of the Polish President Lech ...nuclear weapons if 164 See the Polish President Lech Kaczyński speech cited in “Umowa w sprawie tarczy podpisana (Anti

"Youth" Making Us Fit: On Europe as Operator of Political Technologies

ERIC Educational Resources Information Center

Olsson, Ulf; Petersson, Kenneth; Krejsler, John B.

2011-01-01

This article problematizes the construction of youth as a "driving force" in the contemporary configuration of the European Union (EU) as an educational and political space. The study draws empirical nourishment out of documents that are central to the ongoing formation of the Union, be it White Papers, scripts or memos concerning…

The Efficiency of Public Spending on Education: An Empirical Comparison of EU Countries

ERIC Educational Resources Information Center

Agasisti, Tommaso

2014-01-01

Recent policy suggestions from the European Community underlined the importance of "efficiency" and "equity" in the provision of education while, at the same time, the European countries are required to provide their educational services by minimizing the amount of public money devoted to them. In this article, an empirical…

First-principle study of phosphors for white-LED applications : absorption and emission energies for Ce- and Eu-doped hosts.

NASA Astrophysics Data System (ADS)

Gonze, Xavier; Jia, Yongchao; Miglio, Anna; Giantomassi, Matteo; Ponce, Samuel; Mikami, Masayoshi

After the invasion of compact fluorescent lamps, white LED lighting is becoming a major contender in ecofriendly light sources, with a combination of yellow-, green- and/or red-emitting phosphors partly absorbing the blue light emitted by an InGaN LED. After introducing the semi-empirical Dorenbos model for 4f' 5d transition energies of rare earth ions, I present a first-principle study of two dozen compounds, pristine as well as doped with Ce3+ or Eu2+ ions, in view of explaining their different emission color. The neutral excitation of the ions is simulated through a constrained density functional theory method coupled with a delta SCF analysis of total energies, yielding absorption energies. Then, atomic positions in the excited state are relaxed, yielding emission energies and Stokes shifts, and identification of luminescent centers. In case of the Ce doped materials, the first-principle approach matches experimental data within 0.3 eV for both absorption and emission energies, covering a range of values between 2.0 eV and 5.0 eV, and provides Stokes shifts within 30%, with two exceptions. This is significantly better than the semi-empirical Dorenbos model. A similar analysis is performed for Eu-doped materials, also examining the thermal quenching of two oxynitride hosts. The work was supported by the FRS-FNRS Belgium (PDR Grant T.0238.13 - AIXPHO).

Abnormal Eu behavior at formation of H2O- and Cl-bearing fluids during degassing of granite magmas

NASA Astrophysics Data System (ADS)

Lukanin, Oleg

2010-05-01

One of the important features of REE behavior in the process of decompression degassing of granite melts is the presence of europium anomalies in REE spectrum of forming fluid phase. Negative Eu anomaly in REE spectrum of fluids enriched by chlorine that were formed under high pressures at early stages of degassing relative to REE spectrum of granite melts may take place. Negative Eu anomaly in fluid is replaced by positive one with pressure decrease and decline of Cl concentration in fluid [1, 2]. Observable unique features of europium redistribution between fluid and melt find an explanation in such a fact that Eu in contrast to the other REE under oxidation-reduction conditions, being typical for magmatic process, is present in acidic silica-alumina melts in two valency forms Eu3+ and Eu2+ whereas the dominant form for the other REE in such a melts is (REE)3+ [3, 4]. From the analysis of melt-fluid exchange reactions with participation of two valency forms of europium Eu3+ and Eu2+ follows that the total distribution coefficient of Eu between fluid and melt D(Eu)f-m is equal as a first approximation to [5, 6]: D(Eu)f-m = a1α [C(Cl)f]3 + a2 (1 - α)[C(Cl)f]2, where C(Cl)f - the concentration of Cl in fluid, α = Eu3+/(Eu3+ + Eu2+), i.e. fraction of Eu3+ from the general amount of europium in the melt, and, a1anda2- constants that can be approximately estimated from empirical data upon Eu fluid/melt distribution. The equation given allows to estimate the influence of oxidizing condition of europium on sign and size of Eu anomaly, which is expressed by Eu/Eu# ratio, where Eu is real concentration of europium in fluid being in equilibrium with melt with constant Eu3+/(Eu3+ + Eu2+) ratio, and Eu# is possible "virtual" concentration of europium that could be in the same fluid provided that all europium as other REE as well were exclusively present in trivalent form. The sign and size of Eu anomaly in fluid depends upon Cl concentration in fluid and Eu3+/Eu2+ ratio in melt. The abnormal behavior of Eu shows itself the stronger, the lower fO2and, accordingly, the more fraction of Eu2+is present in melt. The work is supported of the Geosciences Department of the Russian Academy of Science (the program 2- 2010) and RFBR (grant 08-05-00022). References [1] Reed M.J., Candela Ph.A., Piccoli Ph.M. Contrib. Mineral. Petrol. 2000. V. 140. P. 251-262. [2] Lukanin O.A., Dernov-Pegarev V.F. Vestnik Otd. Nauk Zemle RAN, No 1(25)'2007 URL: http://www.scgis.ru/russian/cp1251/h_dgggms/1-2007/informbul-1_2007/term-30e.pdf [3] Drake M.J. Geochim. Cosmochim. Acta. 1975. V. 39. P. 55-64. [4] Wilke M. Behrens H. Contrib. Mineral. Petrol. 1999. V. 137. P. 102-114. [5] Lukanin O.A. Vestnik Otd. Nauk o Zemle RAN, No 1(26)'2008. URL: http://www.scgis.ru/russian/cp1251/h_dgggms/1-2008/informbul-1_2008/magm-20e.pdf [6] Lukanin O.A., Dernov-Pegarev V.F. Geochemistry International, 2010 (in press)

"Sampanis v. Greece": Discrimination, Disrespect, and Romani Identity on the EU Frontier

ERIC Educational Resources Information Center

New, William S.

2012-01-01

This article examines Greek Romani identity from an exogenous viewpoint focused not on who Romani people think and feel they are, but on what others make of them, through official discourse, political action, and educational policy. This article combines a normative argument about social justice as recognition (Axel Honneth) with an empirical case…

Can Students' Concept of Learning Influence Their Learning Outcomes?

ERIC Educational Resources Information Center

Marouchou, Despina Varnava

2012-01-01

This paper aims to readdress the lack of empirical data concerning university learning and in particular the dynamics students' conceptions of learning may have on students' learning outcomes. This paper is written at a time when the EU commission for Higher Education (HE) through the Bologna Process declaration has put into action, since 1999, a…

Determinants of Mobility of Students in Europe: Empirical Evidence for the Period 1998-2009

ERIC Educational Resources Information Center

Caruso, Raul; de Wit, Hans

2015-01-01

This article studies the economic determinants of intra-European student mobility. We constructed a panel of 33 European countries for the period 1998-2009. The dependent variable is the inflow of foreign students (International Standard Classification of Education [ISCED] 5-6) from European Union (EU)-27, European Economic Area (EEA), and…

A Eu(II)-Containing Cryptate as a Redox Sensor in Magnetic Resonance Imaging of Living Tissue.

PubMed

Ekanger, Levi A; Polin, Lisa A; Shen, Yimin; Haacke, E Mark; Martin, Philip D; Allen, Matthew J

2015-11-23

The Eu(II) ion rivals Gd(III) in its ability to enhance contrast in magnetic resonance imaging. However, all reported Eu(II)-based complexes have been studied in vitro largely because the tendency of Eu(II) to oxidize to Eu(III) has been viewed as a major obstacle to in vivo imaging. Herein, we present solid- and solution-phase characterization of a Eu(II)-containing cryptate and the first in vivo use of Eu(II) to provide contrast enhancement. The results indicate that between one and two water molecules are coordinated to the Eu(II) core upon dissolution. We also demonstrate that Eu(II)-based contrast enhancement can be observed for hours in a mouse. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Environmental Kuznets curve for EU agriculture: empirical evidence from new entrant EU countries.

PubMed

Zafeiriou, Eleni; Sofios, Spyros; Partalidou, Xanthi

2017-06-01

The present work examines the intertemporal causal relationship between environmental damage from carbon emissions released by agriculture per 1000 ha of utilized agriculture area and economic performance in the sector of agriculture as described by net value added per capita. The autoregressive distributed lag bounds testing approach is employed to examine this linkage, for three new entrant EU countries, namely, Bulgaria, Czech Republic, and Hungary. The environmental Kuznets hypothesis is confirmed in the long run for Bulgaria and Czech Republic while in the short run is validated only for the case of Czech Republic. The results indicate that the adoption of environment-friendly farming practices and crops' selection does not secure simultaneous high economic and environmental performance at least in the short run for our sample countries and also in the long run for Hungary necessitating the modification of the agro-environmental measures adopted to make those two targets complementary and not mutually exclusive for a farmer.

Structural precaution: the application of premarket approval schemes in EU food legislation.

PubMed

van der Meulen, Bernd M J; Bremmers, Harry J; Wijnands, Jo H M; Poppe, Krijn J

2012-01-01

Structural precaution refers to legal requirements by which food products (whether as ingredients, additives, genetically modified or innovative in some other form) are only admitted to the market after authorization by public authorities and till then are presumed unsafe. In the EU such authorization is granted after provision of conclusive scientific evidence of the product's safety by the applicant. The objective of this article is to critically evaluate structural precaution in the EU against the general principles of European and international law. Moreover, it addresses the positive and negative side-effects of structural precaution for food businesses. The methods which are applied are legal-systematic and empirical. Legal-systematic research shows that the European system of structural precaution may come into conflict with the principles of free trade. Empirical research on the effects of structural precaution shows that the barriers to market access impede food innovations, negatively impact competitiveness, and induce opportunistic strategic responses by food businesses. Among the opportunistic strategic responses that were identified are window-dressing, trespassing and circumventing. These may have adverse effects on food safety. This is remarkable since food safety is the key driving force behind the application of structural precaution. The article advocates an overhaul of the present European risk prevention framework. It argues that the newly proposed European legal framework for innovative foods only partly addresses the identified problems with which the food industry is confronted. Supplementary to legal-systematic overhaul, authorities should invest in accessibility and transparency of the legal framework and provide compliance assistance to reduce regulatory burdens.

Synthesis and characterization of Eu{sup 3+}-doped CaZrO{sub 3}-based perovskite-type phosphors. Part I: Determination of the Eu{sup 3+} occupied site using the ALCHEMI technique

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sakaida, Satoshi; Shimokawa, Yohei; Asaka, Toru

2015-07-15

Highlights: • Eu{sup 3+}-doped CaZrO{sub 3}-based compounds were synthesized by the solid state reaction. • PL emission intensity at 614 nm was changed by the second dopant cations. • The site substituted by Eu{sup 3+} cations was investigated by using XRD and ALCHEMI technique. • The dominant Eu{sup 3+} substitution site was found as the B site (Zr{sup 4+}) in the CaZrO{sub {sup 3}}. • The dominant Eu{sup 3+} substitution site could be strongly influenced by the co-dopants. - Abstract: Eu{sup 3+}-doped CaZrO{sub 3}, SrZrO{sub 3}, and Mg{sup 2+}- or Sr{sup 2+}-co-doped CaZrO{sub 3} were synthesized by conventional solid statemore » reaction and their photoluminescence (PL) properties were characterized. The Eu{sup 3+}-doped CaZrO{sub 3}-based compounds exhibited characteristic emissions of Eu{sup 3+} (f–f transition). The intensity of the main PL emission peak at 614 nm increased with Mg{sup 2+} co-doping, while it decreased with the amount of co-doped Sr{sup 2+}. The site substituted by Eu{sup 3+} cations in the CaZrO{sub 3}-based compounds was investigated by X-ray diffraction analysis and energy-dispersive X-ray analysis based on the electron channeling effects in transmission electron microscopy. The Eu{sup 3+} cations were determined to occupy mainly the B site (Zr{sup 4+}) in CaZrO{sub 3}. The dominant Eu{sup 3+} substitution site was also strongly influenced by the co-dopant, and the ionic radius of the co-dopant was identified as an important factor that determines the dominant Eu{sup 3+} substitution site.« less

Diagnostic criteria for the characterization of quasireversible electron transfer reactions by cyclic square wave voltammetry.

PubMed

Mann, Megan A; Helfrick, John C; Bottomley, Lawrence A

2014-08-19

Theory for cyclic square wave voltammetry of quasireversible electron transfer reactions is presented and experimentally verified. The impact of empirical parameters on the shape of the current-voltage curve is examined. From the trends, diagnostic criteria enabling the use of this waveform as a tool for mechanistic analysis of electrode reaction processes are presented. These criteria were experimentally confirmed using Eu(3+)/Eu(2+), a well-established quasireversible analyte. Using cyclic square wave voltammetry, both the electron transfer coefficient and rate were calculated for this analyte and found to be in excellent agreement with literature. When properly applied, these criteria will enable nonexperts in voltammetry to assign the electrode reaction mechanism and accurately measure electrode reaction kinetics.

Red Luminescent Eu(III) Coordination Bricks Excited on Blue LED Chip.

PubMed

Koizuka, Toru; Yanagisawa, Kei; Hirai, Yuichi; Kitagawa, Yuichi; Nakanishi, Takayuki; Fushimi, Koji; Hasegawa, Yasuchika

2018-06-18

Three types of red luminescent Eu(III) complexes with Schiff base and hfa ligands (hfa: hexafluoroacetylacetonate), mononuclear [Eu(hfa) 2 (OAc)(salen) 2 ] (OAc: acetate anion, salen: N,N'-bis(salicylidene)ethylenediamine), brick-type [Eu 2 (hfa) 4 (OAc) 2 (salbn) 2 ] (salbn: N,N'-bis(salicylidene)-1,4-butanediamine), and polynuclear [Eu(hfa) 2 (OAc)(salhen)] n (salhen: N,N'-bis(salicylidene)-1,6-hexanediamine) are reported for white light-emitting diode (LED) devices. Among these complexes, brick-type [Eu 2 (hfa) 4 (OAc) 2 (salbn) 2 ] excited by blue light (460 nm) exhibits the photosensitized quantum yield (Φ π-π* = 47%) and remarkably high efficiency of sensitization (η sens = 96%). The efficiency of sensitization is caused by the excited state based on ligand-ligand interaction between the Schiff base and hfa ligands in Eu(III) complexes. To fabricate LED devices, the red luminescent [Eu 2 (hfa) 4 (OAc) 2 (salbn) 2 ] was mounted on an InGaN blue LED chip.

Evaluation of Eu(II) -based positive contrast enhancement after intravenous, intraperitoneal, and subcutaneous injections.

PubMed

Ekanger, Levi A; Polin, Lisa A; Shen, Yimin; Haacke, E Mark; Allen, Matthew J

2016-07-01

Eu(II) -based contrast agents offer physiologically relevant, metal-based redox sensing that is unachievable with Gd(III) -based contrast agents. To evaluate the in vivo contrast enhancement of Eu(II) as a function of injection type, we performed intravenous, intraperitoneal, and subcutaneous injections in mice. Our data reveal a correlation between reported oxygen content and expected rates of diffusion with the persistence of Eu(II) -based contrast enhancement. Biodistribution studies revealed europium clearance through the liver and kidneys for intravenous and intraperitoneal injections, but no contrast enhancement was observed in organs associated with clearance. These data represent a step toward understanding the behavior of Eu(II) -based complexes in vivo. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Contrasting Cu-Au and Sn-W Granite Metallogeny through the Zircon Geochemical and Isotopic Record

NASA Astrophysics Data System (ADS)

Gardiner, Nicholas; Hawkesworth, Chris; Robb, Laurence; Whitehouse, Martin; Roberts, Nick; Kirkland, Chris

2017-04-01

Magmatic genesis and evolution - mediated by geodynamic setting - exert a primary control on the propensity of granites to be metal fertile. A revolution in our understanding of these petrogenetic processes has been made through a range of mineral-based tools, most notably the common accessory mineral zircon. There is consequently considerable interest in whether the geochemical and isotopic compositions of zircon can be applied to metallogenic problems. The paired magmatic belts of Myanmar have broadly contrasting metallogenic affinities (Sn-W versus Cu-Au), and are interpreted to have formed on the accretionary margin of the subducting Neo-Tethys Ocean. They therefore present the opportunity to geochemically compare and contrast the zircon compositions in two end-member types of granite-hosted mineral deposits generated in collisional settings. We present an integrated zircon isotope (U-Pb, Lu-Hf, O) and trace element dataset that fingerprint: (a) source; (b) redox conditions; and (c) degree of fractionation. These variables all impact on magma fertility, and our key question to address is whether they can be reliably traced and calibrated within the Myanmar zircon record. Granitoid-hosted zircons from the I-type copper arc have juvenile ɛHf (+7 to +12) and mantle-like δ18O (5.3 ‰), whereas zircons from the S-type tin belt have low ɛHf (-7 to -13) and heavier δ18O (6.2-7.7 ‰). Plotting Hf versus U/Yb reaffirms that the tin belt magmas contain greater crustal contributions than the copper arc rocks. Links between whole rock Rb/Sr and zircon Eu/Eu* highlights that the latter can be used to monitor magma fractionation in systems that crystallize plagioclase (low Sr/Y). Ce/Ce* and Eu/Eu* in zircon are thus sensitive to redox and fractionation respectively, and can be used to evaluate the sensitivity of zircons to the metallogenic affinity of their host rocks. Tin contents that exceed the solubility limit are required in order to make a magmatic-hydrothermal deposit, and empirical observations suggest that this threshold may be marked by zircon Eu/Eu* values of ca. < 0.08. The isotope and trace element signatures of both magmatic and detrital zircons can be developed into a useful exploration tool.

Luminescence properties and energy transfer of site-sensitive Ca(6-x-y)Mg(x-z)(PO(4))(4):Eu(y)(2+),Mn(z)(2+) phosphors and their application to near-UV LED-based white LEDs.

PubMed

Kwon, Ki Hyuk; Im, Won Bin; Jang, Ho Seong; Yoo, Hyoung Sun; Jeon, Duk Young

2009-12-21

On the basis of the structural information that the host material has excellent charge stabilization, blue-emitting Ca(6-x-y)Mg(x)(PO(4))(4):Eu(y)(2+) (CMP:Eu(2+)) phosphors were synthesized and systematically optimized, and their photoluminescence (PL) properties were evaluated. Depending upon the amount of Mg added, the emission efficiency of the phosphors could be enhanced. The substitution of Eu(2+) affected their maximum wavelength (lambda(max)) and thermal stability because the substitution site of Eu(2+) could be varied. To obtain single-phase two-color-emitting phosphors, we incorporated Mn(2+) into CMP:Eu(2+) phosphors. Weak red emission resulting from the forbidden transition of Mn(2+) could be enhanced by the energy transfer from Eu(2+) to Mn(2+) that occurs because of the spectral overlap between the photoluminescence excitation (PLE) spectrum of Mn(2+) and the PL spectrum of Eu(2+). The energy transfer process was confirmed by the luminescence spectra, energy transfer efficiency, and decay curve of the phosphors. Finally, the optimized Ca(6-x-y)Mg(x-z)(PO(4))(4):Eu(y)(2+),Mn(z)(2+) (CMP:Eu(2+),Mn(2+)) phosphors were applied with green emitting Ca(2)MgSi(2)O(7):Eu(2+) (CMS:Eu(2+)) phosphors to ultraviolet (UV) light emitting diode (LED)-pumped white LEDs. The CMS:Eu(2+)-mixed CMP:Eu(2+), Mn(2+)-based white LEDs showed an excellent color rendering index (CRI) of 98 because of the broader emission band and more stable color coordinates than those of commercial Y(3)Al(5)O(12):Ce(3+) (YAG:Ce(3+))-based white LEDs under a forward bias current of 20 mA. The fabricated white LEDs showed very bright natural white light that had the color coordinate of (0.3288, 0.3401), and thus CMP:Eu(2+),Mn(2+) could be regarded as a good candidate for UV LED-based white LEDs.

The Impact of ICT on Educational Performance and its Efficiency in Selected EU and OECD Countries: A Non-Parametric Analysis

ERIC Educational Resources Information Center

Aristovnik, Aleksander

2012-01-01

The purpose of the paper is to review some previous researches examining ICT efficiency and the impact of ICT on educational output/outcome as well as different conceptual and methodological issues related to performance measurement. Moreover, a definition, measurements and the empirical application of a model measuring the efficiency of ICT use…

Impact of Initiatives to Implement Science Inquiry: A Comparative Study of the Turkish, Israeli, Swedish and Czech Science Education Systems

ERIC Educational Resources Information Center

Heinz, Jana; Enghag, Margareta; Stuchlikova, Iva; Cakmakci, Gultekin; Peleg, Ran; Baram-Tsabari, Ayelet

2017-01-01

This empirical study investigates factors that influence the implementation of science inquiry in the education systems of Turkey, Israel, Sweden and the Czech Republic. Data was collected by means of recordings of science experts' discussions as part of an EU-funded project called Science-Teacher Education Advanced Methods (2009-2012). Results of…

Eu oxidation state in fluorozirconate-based glass ceramics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Henke, B.; Passlick, C.; Keil, P.

2009-12-01

The influence of InF{sub 3} doping and remelting on Eu-doped fluorozirconate-based glass ceramics was investigated using near-edge x-ray absorption and optical spectroscopy. It was found that the addition of InF{sub 3} to the melt decreases the Eu{sup 2+}/Eu{sup 3+} mole ratio, while remelting leads to a significant change in the Eu{sup 2+}/Eu{sup 3+} ratio in favor of Eu{sup 2+}. Photoluminescence spectroscopy shows that additional annealing steps lead to the formation of BaCl{sub 2} nanoparticles in the glass. In as-made glass ceramics containing InF{sub 3}, a phase transition of the nanoparticles from hexagonal to orthorhombic structure is observed. This phase transitionmore » is not observed in the remelted glasses studied here.« less

High-skilled labour mobility in Europe before and after the 2004 enlargement

PubMed Central

Puliga, Michelangelo

2017-01-01

The extent to which international high-skilled mobility channels are forming is a question of great importance in an increasingly global knowledge-based economy. One factor facilitating the growth of high-skilled labour markets is the standardization of certifiable degrees meriting international recognition. Within this context, we analysed an extensive high-skilled mobility database comprising roughly 382 000 individuals from five broad profession groups (Medical, Education, Technical, Science & Engineering and Business & Legal) over the period 1997–2014, using the 13-country expansion of the European Union (EU) to provide insight into labour market integration. We compare the periods before and after the 2004 enlargement, showing the emergence of a new east–west migration channel between the 13 mostly eastern EU entrants (E) and the rest of the western European countries (W). Indeed, we observe a net directional loss of human capital from E → W, representing 29% of the total mobility after 2004. Nevertheless, the counter-migration from W → E is 7% of the total mobility over the same period, signalling the emergence of brain circulation within the EU. Our analysis of the country–country mobility networks and the country–profession bipartite networks provides timely quantitative evidence for the convergent integration of the EU, and highlights the central role of the UK and Germany as high-skilled labour hubs. We conclude with two data-driven models to explore the structural dynamics of the mobility networks. First, we develop a reconfiguration model to explore the potential ramifications of Brexit and the degree to which redirection of high-skilled labourers away from the UK may impact the integration of the rest of the European mobility network. Second, we use a panel regression model to explain empirical high-skilled mobility rates in terms of various economic ‘push–pull’ factors, the results of which show that government expenditure on education, per capita wealth, geographical proximity and labour force size are significant attractive features of destination countries. PMID:28298610

High-skilled labour mobility in Europe before and after the 2004 enlargement.

PubMed

Petersen, Alexander M; Puliga, Michelangelo

2017-03-01

The extent to which international high-skilled mobility channels are forming is a question of great importance in an increasingly global knowledge-based economy. One factor facilitating the growth of high-skilled labour markets is the standardization of certifiable degrees meriting international recognition. Within this context, we analysed an extensive high-skilled mobility database comprising roughly 382 000 individuals from five broad profession groups (Medical, Education, Technical, Science & Engineering and Business & Legal) over the period 1997-2014, using the 13-country expansion of the European Union (EU) to provide insight into labour market integration. We compare the periods before and after the 2004 enlargement, showing the emergence of a new east-west migration channel between the 13 mostly eastern EU entrants (E) and the rest of the western European countries (W). Indeed, we observe a net directional loss of human capital from E → W, representing 29% of the total mobility after 2004. Nevertheless, the counter-migration from W → E is 7% of the total mobility over the same period, signalling the emergence of brain circulation within the EU. Our analysis of the country-country mobility networks and the country-profession bipartite networks provides timely quantitative evidence for the convergent integration of the EU, and highlights the central role of the UK and Germany as high-skilled labour hubs. We conclude with two data-driven models to explore the structural dynamics of the mobility networks. First, we develop a reconfiguration model to explore the potential ramifications of Brexit and the degree to which redirection of high-skilled labourers away from the UK may impact the integration of the rest of the European mobility network. Second, we use a panel regression model to explain empirical high-skilled mobility rates in terms of various economic 'push-pull' factors, the results of which show that government expenditure on education, per capita wealth, geographical proximity and labour force size are significant attractive features of destination countries. © 2017 The Author(s).

Physics of Efficiency Droop in GaN:Eu Light-Emitting Diodes.

PubMed

Fragkos, Ioannis E; Dierolf, Volkmar; Fujiwara, Yasufumi; Tansu, Nelson

2017-12-01

The internal quantum efficiency (IQE) of an electrically-driven GaN:Eu based device for red light emission is analyzed in the framework of a current injection efficiency model (CIE). The excitation path of the Eu +3 ion is decomposed in a multiple level system, which includes the carrier transport phenomena across the GaN/GaN:Eu/GaN active region of the device, and the interactions among traps, Eu +3 ions and the GaN host. The identification and analysis of the limiting factors of the IQE are accomplished through the CIE model. The CIE model provides a guidance for high IQE in the electrically-driven GaN:Eu based red light emitters.

Lanthanide luminescent displacement assays: the sensing of phosphate anions using Eu(III)-cyclen-conjugated gold nanoparticles in aqueous solution.

PubMed

Massue, Julien; Quinn, Susan J; Gunnlaugsson, Thorfinnur

2008-06-04

1.Eu, a cyclen based Eu(III)-thiol conjugate, was incorporated onto the surface of water-soluble gold nanoparticles to give AuNP-1.Eu. The self-assembly between AuNP-1.Eu and the antenna 2 resulted in the formation of the highly luminescent lanthanide system, AuNP-1.Eu-2, at pH 7.4. The sensing of flavin monophosphate 3 is demonstrated, whereby 3 displaced the antenna 2 in AuNP-1.Eu-2, resulting in the formation of AuNP-1.Eu-3 and quenching of the Eu(III) emission.

Investigating the influence on safety of retrofitting Italian motorways with barriers meeting a new EU standard.

PubMed

Cafiso, Salvatore; D'Agostino, Carmelo; Persaud, Bhagwant

2017-04-03

A new European Union (EU) regulation for safety barriers, which is based on performance, has encouraged road agencies to perform an upgrade of old barriers, with the expectation that there will be safety benefits at the retrofitted sites. The new class of barriers was designed and installed in compliance with the 1998 (European Norm) EN 1317 standards for road restraint systems, which lays down common requirements for the testing and certification of road restraint systems in all countries of the European Committee for Standardization (CEN). Both the older and new barriers are made of steel and are installed in such a way as to avoid vehicle intrusion, but the older ones are thought to be only effective at low speeds and large angles of impact. The new standard seeks to remedy this by providing better protection at higher speeds. This article seeks to quantify the effect on the frequency of fatal and injury crashes of retrofitting motorways with barriers meeting the new standards. The estimation of the crash modification was carried out by performing an empirical Bayes before-after analysis based on data from the A18 Messina-Catania motorway in Italy. The methodology has the great advantage to account for the regression to the mean effects. Besides, to account for time trend effects and dispersion of crash data, a modified calibration methodology of safety performance was used. This study, based on data collected on 76 km of motorway in the period 2000-2012, derived Crash Modification Factor point estimates that indicate reductions of 72% for run-off-road fatal and injury crashes and 38% in total fatal and injury crashes that could be expected by upgrading an old safety barrier by complying with new EU 1317 standards. The estimated benefit-cost ratio of 5.57 for total crashes indicates that the treatment is cost effective. The magnitude of this benefit indicates that the retrofits are cost-effective even for total crashes and should continue in any European country inasmuch as the estimated Crash Modification Factors are based on treatment sites that are reasonably representative of all European motorways.

Inorganic scintillation detectors based on Eu-activated phosphors for 192Ir brachytherapy

PubMed Central

Kertzscher, Gustavo; Beddar, Sam

2017-01-01

The availability of real-time treatment verification during high-dose-rate (HDR) brachytherapy is currently limited. Therefore, we studied the luminescence properties of the widely commercially available scintillators using the inorganic materials Eu-activated phosphors Y2O3:Eu, YVO4:Eu, Y2O2S:Eu, and Gd2O2S:Eu to determine whether they could be used to accurately and precisely verify HDR brachytherapy doses in real time. The suitability for HDR brachytherapy of inorganic scintillation detectors (ISDs) based on the 4 Eu-activated phosphors in powder form was determined based on experiments with a 192Ir HDR brachytherapy source. The scintillation intensities of the phosphors were 16 to 134 times greater than that of the commonly used organic plastic scintillator BCF-12. High signal intensities were achieved with an optimized packing density of the phosphor mixture and with a shortened fiber-optic cable. The influence of contaminating Cerenkov and fluorescence light induced in the fiber-optic cable (stem signal) was adequately suppressed by inserting between the fiber-optic cable and the photodetector a 25-nm band-pass filter centered at the emission peak. The spurious photoluminescence signal induced by the stem signal was suppressed by placing a long-pass filter between the scintillation detector volume and the fiber-optic cable. The time-dependent luminescence properties of the phosphors were quantified by measuring the non-constant scintillation during irradiation and the afterglow after the brachytherapy source had retracted. We demonstrated that a mixture of Y2O3:Eu and YVO4:Eu suppressed the time-dependence of the ISDs and that the time-dependence of Y2O2S:Eu and Gd2O2S:Eu introduced large measurement inaccuracies. We conclude that ISDs based on a mixture of Y2O3:Eu and YVO4:Eu are promising candidates for accurate and precise real-time verification technology for HDR BT that is cost effective and straightforward to manufacture. Widespread dissemination of this technology could lead to an improved understanding of error types and frequencies during BT and to improved patient safety during treatment. PMID:28475494

Inorganic scintillation detectors based on Eu-activated phosphors for 192Ir brachytherapy

NASA Astrophysics Data System (ADS)

Kertzscher, Gustavo; Beddar, Sam

2017-06-01

The availability of real-time treatment verification during high-dose-rate (HDR) brachytherapy is currently limited. Therefore, we studied the luminescence properties of the widely commercially available scintillators using the inorganic materials Eu-activated phosphors Y2O3:Eu, YVO4:Eu, Y2O2S:Eu, and Gd2O2S:Eu to determine whether they could be used to accurately and precisely verify HDR brachytherapy doses in real time. The suitability for HDR brachytherapy of inorganic scintillation detectors (ISDs) based on the 4 Eu-activated phosphors in powder form was determined based on experiments with a 192Ir HDR brachytherapy source. The scintillation intensities of the phosphors were 16-134 times greater than that of the commonly used organic plastic scintillator BCF-12. High signal intensities were achieved with an optimized packing density of the phosphor mixture and with a shortened fiber-optic cable. The influence of contaminating Cerenkov and fluorescence light induced in the fiber-optic cable (stem signal) was adequately suppressed by inserting between the fiber-optic cable and the photodetector a 25 nm band-pass filter centered at the emission peak. The spurious photoluminescence signal induced by the stem signal was suppressed by placing a long-pass filter between the scintillation detector volume and the fiber-optic cable. The time-dependent luminescence properties of the phosphors were quantified by measuring the non-constant scintillation during irradiation and the afterglow after the brachytherapy source had retracted. We demonstrated that a mixture of Y2O3:Eu and YVO4:Eu suppressed the time-dependence of the ISDs and that the time-dependence of Y2O2S:Eu and Gd2O2S:Eu introduced large measurement inaccuracies. We conclude that ISDs based on a mixture of Y2O3:Eu and YVO4:Eu are promising candidates for accurate and precise real-time verification technology for HDR BT that is cost effective and straightforward to manufacture. Widespread dissemination of this technology could lead to an improved understanding of error types and frequencies during BT and to improved patient safety during treatment.

International Space

DTIC Science & Technology

2010-03-01

that benefit from the creation of Galileo are the Road, Location Based Services (LBS), Aviation and Agriculture. In all four categories the...to increase economic wealth within the EU. “The term Location Based Services (LBS) covers a broad range of applications that are triggered...applications. 14 http://www.gsa.europa.eu/go/news/ location - based - services -market-ready-for-takeoff. 15 http://www.gsa.europa.eu/go/news/harvesting

Competition between magnetism and superconductivity in Eu-based intermetallic compounds

NASA Astrophysics Data System (ADS)

Stavinoha, Macy; Green, Lance; Chan, Julia; Morosan, Emilia

Eu-based intermetallic compounds present a path to discover new correlated electronic behavior in quantum materials. Reports of superconductivity, intermediate valence behavior, and heavy fermions indicate that Eu-based compounds are promising routes to study the relationship between crystallography and electronic properties. The present work is focused on EuGa4, an antiferromagnet with TN = 16 K isostructural with the tetragonal RT2M2 (R = rare earth, T = transition metal, M = metal or metalloid) family that exhibits heavy fermion behavior and unconventional superconductivity. Single crystals of the doped series (Eu1-xLax)Ga4, (Eu1-xCax)Ga4, and Eu(Ga1-xAlx)4 have been grown using the self-flux method and tested for change in unit cell volume and magnetic susceptibility. Results show that doping with Ca (isoelectronic doping) and La (hole doping) reduce TN to 12.4 K and 2.3 K, respectively, for Ca doping up to x = 0.11 and La doping up to x = 0.74 without an associated change in unit cell volume. The series Eu(Ga1-xAlx)4 has shown incommensurate-to-commensurate magnetic transitions. Future studies will aim to further decrease TN and the unit cell volume using physical pressure and chemical pressure through doping. ICAM, Gordon and Betty Moore Foundation.

Conventional empirical law reverses in the phase transitions of 122-type iron-based superconductors

DOE PAGES

Yu, Zhenhai; Wang, Lin; Wang, Luhong; ...

2014-11-24

Phase transition of solid-state materials is a fundamental research topic in condensed matter physics, materials science and geophysics. It has been well accepted and widely proven that isostructural compounds containing different cations undergo same pressure-induced phase transitions but at progressively lower pressures as the cation radii increases. However, we discovered that this conventional law reverses in the structural transitions in 122-type iron-based superconductors. In this report, a combined low temperature and high pressure X-ray diffraction (XRD) measurement has identified the phase transition curves among the tetragonal (T), orthorhombic (O) and the collapsed-tetragonal (cT) phases in the structural phase diagram ofmore » the iron-based superconductor AFe 2As 2 (A = Ca, Sr, Eu, and Ba). As a result, the cation radii dependence of the phase transition pressure (T → cT) shows an opposite trend in which the compounds with larger ambient radii cations have a higher transition pressure.« less

The convergence of European business cycles 1978-2000

NASA Astrophysics Data System (ADS)

Ormerod, Paul; Mounfield, Craig

2002-05-01

The degree of convergence of the business cycles of the economies of the European Union (EU) is a key policy issue. In particular, a substantial degree of convergence is needed if the European Central Bank is to be capable of setting a monetary policy which is appropriate to the stage of the cycle of the Euro zone economies. We consider the annual rates of real GDP growth on a quarterly basis in the large core economies of the EU (France, Germany and Italy, plus The Netherlands) over the period 1978Q1-2000Q3. An important empirical question is the degree to which the correlations between these growth rates contain true information rather than noise. The technique of random matrix theory is able to answer this question, and has been recently applied successfully in the physics journals to financial markets data. We find that the correlations between the growth rates of the core EU economies contain substantial amounts of true information, and exhibit considerable stability over time. Even in the late 1970s and early 1980s, these economies moved together closely over the course of the business cycle. There was a slight loosening at the time of German re-unification, but the economies are now, if anything, even more closely correlated. As a benchmark for comparison, we add a series to the EU core data set which by construction is uncorrelated with these business cycles. We then analyse the EU core plus Spain, a country which has attached great importance to greater integration with Europe. In the early part of the period examined, the results are very similar to those obtained with the data set of the EU core plus the random series. However, there is a clear trend in the results, which provide strong evidence to support the view that the Spanish economy has now become closely converged with the core EU economies in terms of its movements over the business cycle. In contrast, the results obtained with a data set of the EU core plus the UK show no such trend. In the late 1970s and early 1980s, the UK economy did exhibit some degree of correlation with those of the core EU. However, there is no clear evidence to suggest that the UK business cycle has moved more closely into line with that of the core EU economies over the 1978-2000 period.

Synthesis, characterization, photoluminescence and cytotoxic properties of novel luminescent Eu(III)complexes based on chromone Schiff base

NASA Astrophysics Data System (ADS)

Saif, M.; El-Shafiy, Hoda F.; Mashaly, Mahmoud M.; Eid, Mohamed F.; Nabeel, A. I.; Fouad, R.

2018-06-01

Three novel Eu(III) phosphor complexes, [Eu(HL)(OH2)2(C2H5OH)](NO3)2 (1), [Eu(HL)(Bpy)(NO3)2(EtOH)] (2) and [Eu(HL)(Phen)(NO3)2(H2O)] (3) (HL = (11E)-2-hydroxy-N/-((4-oxo-4H-chromen-3-yl)methylene)benzohydrazide; Bpy = 2,2/-bibyridyl and Phen = 1,10-phenanthroline) were prepared. Elemental, thermal, FT-IR and XRD methods were used to characterize their structural configuration. The HL behaves as a monoanionic tridentate ligand. The XRD analysis shows that the ligand and its Eu3+complexes are in nano domain. From fluorescence spectroscopy, all the prepared complexes are highly luminescent, having an impressive visual emission under UV excitation. The H2L and its Eu3+nano-complexes (1-3) were tested for their in vitro cytotoxicity against Ehrlich Ascites Carcinoma cell line (EAC). The Eu(III) nano-complexes (1-3) effectively inhibited EAC growth with IC50 value of 25 μM. The high antitumor activity of the Eu(III) nano-complexes (1-3) were attributed to its chemical structure, and nano size properties.

Use of Free/Libre Open Source Software in Sepsis "-Omics" Research: A Bibliometric, Comparative Analysis Among the United States, EU-28 Member States, and China.

PubMed

Evangelatos, Nikolaos; Satyamourthy, Kapaettu; Levidou, Georgia; Brand, Helmut; Bauer, Pia; Kouskouti, Christina; Brand, Angela

2018-05-01

"-Omics" systems sciences are at the epicenter of personalized medicine and public health, and drivers of knowledge-based biotechnology innovation. Bioinformatics, a core component of omics research, is one of the disciplines that first employed Free/Libre Open Source Software (FLOSS), and thus provided a fertile ground for its further development. Understanding the use and characteristics of FLOSS deployed in the omics field is valuable for future innovation strategies, policy and funding priorities. We conducted a bibliometric, longitudinal study of the use of FLOSS in sepsis omics research from 2011 to 2015 in the United States, EU-28 and China. Because sepsis is an interdisciplinary field at the intersection of multiple omics technologies and medical specialties, it was chosen as a model innovation ecosystem for this empirical analysis, which used publicly available data. Despite development of and competition from proprietary commercial software, scholars in omics continue to employ FLOSS routinely, and independent of the type of omics technology they work with. The number of articles using FLOSS increased significantly over time in the EU-28, as opposed to the United States and China (R = 0.96, p = 0.004). Furthermore, in an era where sharing of knowledge is being strongly advocated and promoted by public agencies and social institutions, we discuss possible correlations between the use of FLOSS and various funding sources in omics research. These observations and analyses provide new insights into the use of FLOSS in sepsis omics research across three (supra)national regions. Further benchmarking studies are warranted for FLOSS trends in other omics fields and geographical settings. These could, in time, lead to the development of new composite innovation and technology use metrics in omics systems sciences and bioinformatics communities.

Magnetocaloric behavior in ternary europium indides EuT 5In: Probing the design capability of first-principles-based methods on the multifaceted magnetic materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bigun, Inna; Steinberg, Simon; Smetana, Volodymyr

The most favorable structures and the types of magnetic ordering predicted from first-principles-based methods in a family of closely related transition-metal-rich indides EuT 5In (T = Cu, Ag, Au) are gauged against relevant experiments. The EuT5In compounds adopt a different structure for each different coinage metal—EuCu 5In ( hR42; Rmore » $$\\overline{3}$$m, a = 5.0933(7), c = 30.557(6) Å), EuAg 5In ( oP28; Pnma, a = 9.121(2), b = 5.645(1), c = 11.437(3) Å), and EuAu 5In ( tI14; I4/ mmm, a = 7.1740(3), c = 5.4425(3) Å)—and crystallize with the Sr 5Al 9, CeCu 6, and YbMo 2Al 4 structure types, respectively. EuCu 5In and EuAg 5In order antiferromagnetically at T N = 12 and 6 K, respectively, whereas EuAu 5In is ferromagnetic below T C = 13 K. EuCu 5In exhibits complex magnetism: after the initial drop at T N, the magnetization rises again below 8 K, and a weak metamagnetic-like transition occurs at 2 K in μ 0H = 1.8 T. The electronic heat capacity of EuCu 5In, γ = ~400 mJ/(mol K 2), points to strong electronic correlations. Spin-polarized densities of states suggest that the magnetic interactions in the three materials studied are supported via mixing 4 f and 5 d states of Eu. As a result, a chemical bonding analysis based on the Crystal Orbital Hamilton populations reveals the tendency to maximize overall bonding as a driving force to adopt a particular type of crystal structure.« less

Magnetocaloric behavior in ternary europium indides EuT 5In: Probing the design capability of first-principles-based methods on the multifaceted magnetic materials

DOE PAGES

Bigun, Inna; Steinberg, Simon; Smetana, Volodymyr; ...

2017-01-27

The most favorable structures and the types of magnetic ordering predicted from first-principles-based methods in a family of closely related transition-metal-rich indides EuT 5In (T = Cu, Ag, Au) are gauged against relevant experiments. The EuT5In compounds adopt a different structure for each different coinage metal—EuCu 5In ( hR42; Rmore » $$\\overline{3}$$m, a = 5.0933(7), c = 30.557(6) Å), EuAg 5In ( oP28; Pnma, a = 9.121(2), b = 5.645(1), c = 11.437(3) Å), and EuAu 5In ( tI14; I4/ mmm, a = 7.1740(3), c = 5.4425(3) Å)—and crystallize with the Sr 5Al 9, CeCu 6, and YbMo 2Al 4 structure types, respectively. EuCu 5In and EuAg 5In order antiferromagnetically at T N = 12 and 6 K, respectively, whereas EuAu 5In is ferromagnetic below T C = 13 K. EuCu 5In exhibits complex magnetism: after the initial drop at T N, the magnetization rises again below 8 K, and a weak metamagnetic-like transition occurs at 2 K in μ 0H = 1.8 T. The electronic heat capacity of EuCu 5In, γ = ~400 mJ/(mol K 2), points to strong electronic correlations. Spin-polarized densities of states suggest that the magnetic interactions in the three materials studied are supported via mixing 4 f and 5 d states of Eu. As a result, a chemical bonding analysis based on the Crystal Orbital Hamilton populations reveals the tendency to maximize overall bonding as a driving force to adopt a particular type of crystal structure.« less

Design and synthesis of novel adenine fluorescence probe based on Eu(III) complexes with dtpa-bis(guanine) ligand

NASA Astrophysics Data System (ADS)

Tian, Fengyun; Jiang, Xiaoqing; Dou, Xuekai; Wu, Qiong; Wang, Jun; Song, Youtao

2017-05-01

A novel adenine (Ad) fluorescence probe (EuIII-dtpa-bis(guanine)) was designed and synthesized by improving experimental method based on the Eu(III) complex and dtpa-bis(guanine) ligand. The dtpa-bis(guanine) ligand was first synthesized by the acylation action between dtpaa and guanine (Gu), and the corresponding Eu(III) complex was successfully prepared through heat-refluxing method with dtpa-bis(guanine) ligand. As a novel fluorescence probe, the EuIII-dtpa-bis(guanine) complex can detect adenine (Ad) with characteristics of strong targeting, high specificity and high recognition ability. The detection mechanism of the adenine (Ad) using this probe in buffer solution was studied by ultraviolet-visible (UV-vis) and fluorescence spectroscopy. When the EuIII-dtpa-bis(guanine) was introduced to the adenine (Ad) solution, the fluorescence emission intensity was significantly enhanced. However, adding other bases such as guanine (Gu), xanthine (Xa), hypoxanthine (Hy) and uric acid (Ur) with similar composition and structure to that of adenine (Ad) to the EuIII-dtpa-bis(guanine) solution, the fluorescence emission intensities are nearly invariable. Meanwhile, the interference of guanine (Gu), xanthine (Xa), hypoxanthine (Hy) and uric acid (Ur) on the detection of the adenine using EuIII-dtpa-bis(guanine) probe was also studied. It was found that presence of these bases does not affect the detection of adenine (Ad). A linear response of fluorescence emission intensities of EuIII-dtpa-bis(guanine) at 570 nm as a function of adenine (Ad) concentration in the range of 0.00-5.00 × 10- 5 mol L- 1 was observed. The detection limit is about 4.70 × 10- 7 mol L- 1.

Tunable luminescence of the full-color-emitting LiGd5P2O13:Bi3+,Eu3+ phosphor based on energy transfers

NASA Astrophysics Data System (ADS)

Wang, Lei; Qiao, Jianwei; Liu, Yongfu; Huang, Ping; Shi, Qiufeng; Tian, Yue; Cui, Cai'e.; Luo, Zhaohua

2017-05-01

A series of Bi3+ and/or Eu3+ doped LiGd5P2O13 (LGPO) were synthesized via a solid state reaction. In the LiGd5P2O13 lattice, Bi3+ shows a broad bluish-green emission around 500 nm and Eu3+ exhibits typical f-f red emissions. Based on the Bi3+ → Eu3+ energy transfers, the luminescence colors can be tuned from bluish-green to orange by altering the Bi3+/Eu3+ ratio. Under the 290 nm excitation, the sample with optimal composition of LGPO:0.1Bi3+,0.01Eu3+ exhibits a white light emission with a CRI of 82 and a CCT of 4250 K. The energy transfer mechanism from Bi3+ to Eu3+ in the LiGd5P2O13 host was ascribed to the dipole-dipole interaction.

Does the EU sugar policy reform increase added sugar consumption? An empirical evidence on the soft drink market.

PubMed

Bonnet, Céline; Requillart, Vincent

2011-09-01

Whereas National Health authorities recommend a decrease in the consumption of 'added' sugar, a reform on the sugar market will lead to a 36% decrease of the sugar price in the EU. Using French data on soft drinks purchases, this paper investigates the anticipated impact of this reform on the consumption of sugar-sweetened beverages. The reform of the EU sugar policy leads to a decrease in regular soft drink prices by 3% and varies across brands. To assess substitution within this food category, we use a random-coefficients logit model that takes into account a large number of differentiated products and heterogeneity in consumers' behavior. Results suggest that price changes would lead to an increase in market shares of regular products by 7.5% and to substitutions between brands to the benefit of products with the highest sugar content. On the whole, it would raise consumption of regular soft drinks by more than 1 litre per person per year and consumption of added sugar by 124 g per person per year, this increase being larger in households composed of overweight and obese individuals. Copyright © 2011 John Wiley & Sons, Ltd.

The Convergence of European Business Cycles 1980--2004

NASA Astrophysics Data System (ADS)

Ormerod, P.

2005-09-01

The degree of convergence of the business cycles of the economies of the European Union is a key policy issue. In particular, a substantial degree of convergence is needed if the European Central Bank is to be capable of setting a monetary policy which is appropriate to the stage of the cycle of the Euro zone economies. I consider the annual rates of real GDP growth on a quarterly basis in the main economies of the EU (France, Germany, Italy, UK, Spain, Belgium and the Netherlands) over the period 1980Q1--2004Q4. An important empirical question is the degree to which the correlations between these growth rates contain true information rather than noise. The technique of random matrix theory is able to answer this question, and has been applied successfully in the physics journals to financial markets data. I find that the correlations between the growth rates of most of the core EU economies contain substantial amounts of true information, and exhibit considerable stability over time. Even in the late 1970s and early 1980s, these economies moved together closely over the course of the business cycle. There was a slight loosening at the time of German re-unification, but the economies have moved back into close synchronisation. The same result holds when Spain is added to the group of core EU countries. However, the problems of the German economy which arose from the early 1990s onwards has led to Germany becoming increasingly less synchronised with the rest of the core EU. Further, the results obtained with a data set of the converged EU core plus the UK show no real convergence between the UK and this group of economies.

Study of Eu{sup 3+} → Eu{sup 2+} reduction in BaAl{sub 2}O{sub 4}:Eu prepared in different gas atmospheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rezende, Marcos V. dos S., E-mail: mvsrezende@gmail.com; Valerio, Mário E.G.; Jackson, Robert A.

2015-01-15

Highlights: • The effect of different gas atmospheres on the Eu reduction process was studied. • The Eu reduction was monitored analyzing XANES region at the Eu L{sub III}-edge. • Hydrogen reducing agent are the most appropriate gas for Eu{sup 2+} stabilization. • Only a part of the Eu ions can be stabilized in the divalent state. • A model of Eu reduction process is proposed. - Abstract: The effect of different gas atmospheres such as H{sub 2}(g), synthetic air, carbon monoxide (CO) and nitrogen (N{sub 2}) on the Eu{sup 3+} → Eu{sup 2+} reduction process during the synthesis ofmore » Eu-doped BaAl{sub 2}O{sub 4} was studied using synchrotron radiation. The Eu{sup 3+} → Eu{sup 2+} reduction was monitored analyzing XANES region when the sample are excited at the Eu L{sub III}-edge. The results show that the hydrogen reducing agent are the most appropriate gas for Eu{sup 2+} stabilization in BaAl{sub 2}O{sub 4} and that only a part of the Eu ions can be stabilized in the divalent state. A model of Eu reduction process, based on the incorporation of charge compensation defects, is proposed.« less

Cell-Based Veterinary Pharmaceuticals – Basic Legal Parameters Set by the Veterinary Pharmaceutical Law and the Genetic Engineering Law of the European Union

PubMed Central

Faltus, Timo; Brehm, Walter

2016-01-01

Cell-based therapies have been in use in veterinary medicine for years. However, the legal requirement of manufacturing, placing on the market and use of cell-based veterinary pharmaceuticals are not as well developed as the respective requirements of chemical pharmaceuticals. Cell-based veterinary pharmaceuticals are medicinal products in the sense of the pharmaceutical law of the European Union (EU). For that reason, such medicinal products principally require official approval for their manufacture and an official marketing authorization for their placement on the market before being used by the veterinarian. The manufacture, placing on the market, and use of cell-based veterinary pharmaceuticals without manufacturing approval and marketing authorization is permitted only in certain exceptional cases determined by EU and individual Member State law. Violations of this requirement may have consequences for the respective veterinarian under criminal law and under the code of professional conduct in the respective Member State. The regular use of cell-based veterinary pharmaceuticals within the scope of a therapeutic emergency as well as the import of such veterinary pharmaceuticals from non-European countries for use in the EU are currently out of the question in the EU because of a lack of legal bases. Here, we review the general legal requirement of manufacturing, placing on the market, and use of cell-based veterinary pharmaceuticals within the EU and point out different implementations of EU law within the different Member States. PMID:27965965

Cell-Based Veterinary Pharmaceuticals - Basic Legal Parameters Set by the Veterinary Pharmaceutical Law and the Genetic Engineering Law of the European Union.

PubMed

Faltus, Timo; Brehm, Walter

2016-01-01

Cell-based therapies have been in use in veterinary medicine for years. However, the legal requirement of manufacturing, placing on the market and use of cell-based veterinary pharmaceuticals are not as well developed as the respective requirements of chemical pharmaceuticals. Cell-based veterinary pharmaceuticals are medicinal products in the sense of the pharmaceutical law of the European Union (EU). For that reason, such medicinal products principally require official approval for their manufacture and an official marketing authorization for their placement on the market before being used by the veterinarian. The manufacture, placing on the market, and use of cell-based veterinary pharmaceuticals without manufacturing approval and marketing authorization is permitted only in certain exceptional cases determined by EU and individual Member State law. Violations of this requirement may have consequences for the respective veterinarian under criminal law and under the code of professional conduct in the respective Member State. The regular use of cell-based veterinary pharmaceuticals within the scope of a therapeutic emergency as well as the import of such veterinary pharmaceuticals from non-European countries for use in the EU are currently out of the question in the EU because of a lack of legal bases. Here, we review the general legal requirement of manufacturing, placing on the market, and use of cell-based veterinary pharmaceuticals within the EU and point out different implementations of EU law within the different Member States.

Persistent Luminescence in Non-Eu2+-Doped Compounds: A Review

PubMed Central

Van den Eeckhout, Koen; Poelman, Dirk; Smet, Philippe F.

2013-01-01

During the past few decades, the research on persistent luminescent materials has focused mainly on Eu2+-doped compounds. However, the yearly number of publications on non-Eu2+-based materials has also increased steadily. By now, the number of known persistent phosphors has increased to over 200, of which over 80% are not based on Eu2+, but rather, on intrinsic host defects, transition metals (manganese, chromium, copper, etc.) or trivalent rare earths (cerium, terbium, dysprosium, etc.). In this review, we present an overview of these non-Eu2+-based persistent luminescent materials and their afterglow properties. We also take a closer look at some remaining challenges, such as the excitability with visible light and the possibility of energy transfer between multiple luminescent centers. Finally, we summarize the necessary elements for a complete description of a persistent luminescent material, in order to allow a more objective comparison of these phosphors. PMID:28811409

Dual-Emitting UiO-66(Zr&Eu) Metal-Organic Framework Films for Ratiometric Temperature Sensing.

PubMed

Feng, Ji-Fei; Liu, Tian-Fu; Shi, Jianlin; Gao, Shui-Ying; Cao, Rong

2018-06-20

A novel dual-emitting metal-organic framework based on Zr and Eu, named as UiO-66(Zr&Eu), was built using a clever strategy based on secondary building units. With the use of polymers, the obtained UiO-66(Zr&Eu) was subsequently deposited as thin films that can be utilized as smart thermometers. The UiO-66(Zr&Eu) polymer films can be used for the detection of temperature changes in the range of 237-337 K due to the energy transfer between the lanthanide ions (Eu in clusters) and the luminescent ligands, and the relative sensitivity reaches 4.26% K -1 at 337 K. Moreover, the sensitivity can be improved to 19.67% K -1 by changing the film thickness. In addition, the temperature-sensing performance of the films is superior to that of the powders, and the sensor can be reused 3 times without loss of performance.

The Politics of Global Value Chains: Import-dependent Firms and EU–Asia Trade Agreements

PubMed Central

Eckhardt, Jappe; Poletti, Arlo

2015-01-01

In 2006, the European Commission released its Global Europe Communication, in which it announced a shift from a multilateral to a bilateral trade strategy. One of the key pillars of this new strategy was to strengthen the bilateral trade relations with key Asian countries. In contrast to existing analyses that focus on European Union (EU) decision makers’ agency, we propose an explanation for this notable shift in the EU’s trade policy that stresses the political role of import-dependent firms. In light of the increasing integration of such firms into global value chains, the article argues that a plausible case can be made, both theoretically and empirically, that import-dependent firms had a clear stake in the signing of preferential trade agreements between the EU and Asian countries and that their lobbying efforts significantly affected the EU’s decision to start negotiations with South Korea, India and Vietnam. PMID:28018131

Conjunctive Cohesion in English Language EU Documents--A Corpus-Based Analysis and Its Implications

ERIC Educational Resources Information Center

Trebits, Anna

2009-01-01

This paper reports the findings of a study which forms part of a larger-scale research project investigating the use of English in the documents of the European Union (EU). The documents of the EU show various features of texts written for legal, business and other specific purposes. Moreover, the translation services of the EU institutions often…

On the application of CaF2:Eu and SrF2:Eu phosphors in LED based phototherapy lamp

NASA Astrophysics Data System (ADS)

Belsare, P. D.; Moharil, S. V.; Joshi, C. P.; Omanwar, S. K.

2013-06-01

In the last few years the interest of scientific community has been increased towards solid state lighting based on LEDs because of their superior advantages over the conventional fluorescent lamps. As the GaN based LEDs are easily available efforts of the researchers are now on making the new phosphors which are excitable in the near UV region (360-400nm) for solid state lighting. This paper reports the photoluminescence characteristics of CaF2:Eu and SrF2:Eu phosphor prepared by wet chemical method. The violet emission of these phosphors with near UV excitation can be useful in making a phototherapy lamp based on LEDs for treating various skin diseases like acne vulgaris and hyperbilirubinemia.

A Smart Social Inclusion Policy for the EU: The Role of Education and Training

ERIC Educational Resources Information Center

Nicaise, Ides

2012-01-01

Whereas in 2000 the EU had heralded the knowledge-based society with as its motto "with more and better jobs and stronger social cohesion", the past decade has led to greater inequality and (at best) a status-quo in poverty. EU2020 seems to acknowledge this failure and aims to reconnect social inclusion with the knowledge-based strategy.…

Chemistry of the Apollo 11 highland component

NASA Technical Reports Server (NTRS)

Laul, J. C.; Papike, J. J.; Simon, S. B.; Shearer, C. K.

1983-01-01

Thirty-eight Apollo 11 lunar highland fragments from coarse fines 10085 have been subjected to petrologic and chemical study. Six major chemical groups are identified: (a) high-K KREEP; (b) anorthosite with a 10X chondrite positive Eu anomaly and anorthosite with 30X positive Eu anomaly; (c) ANT; (d) LKFM; (e) anorthositic gabbro with no Eu anomaly, with a positive Eu anomaly, and with a negative Eu anomaly; and (f) dominant Highland component, 2X-10X chondrite with a positive 10X-14X Eu anomaly. Newly recognized groups are presented based on the REE patterns: (a) ANT group with 5X La and a 22X positive Eu anomaly; (b) 10X flat with 14X positive Eu anomaly; and (c) 2-3X flat with a 10X positive Eu anomaly. The highland suite is very low in K and REE, and is overall quite similar to the Apollo 16 suite.

Creating Undocumented EU Migrants through Welfare: A Conceptualization of Undeserving and Precarious Citizenship

PubMed Central

Mescoli, Elsa

2018-01-01

Following the financial and economic crisis, welfare policies across the EU are increasingly becoming instruments for limiting the mobility of certain EU migrants. In this article, we focus on EU citizens who see their freedom of movement in the EU being restricted after they have applied for social assistance or unemployment benefits in their country of residence. Doing so, we conceptualize undocumented EU migration by means of the concepts of ‘non-deportability’, ‘deservingness’ and ‘precariousness’. Overall, this article – based on ethnographic fieldwork conducted with Italian migrants in Belgium – expands our understanding of undocumented migration by demonstrating how arbitrary and intimidating bureaucratic processes undermine the exercise of EU citizenship. PMID:29899582

Varying Eu2+ magnetic order by chemical pressure in EuFe2(As1-xPx)2

NASA Astrophysics Data System (ADS)

Zapf, S.; Wu, D.; Bogani, L.; Jeevan, H. S.; Gegenwart, P.; Dressel, M.

2011-10-01

Based on low-field magnetization measurements on a series of single crystals, we present a scheme of the Eu2+ spin alignment in EuFe2(As1-xPx)2. We explain observations of the Eu2+ ordering previously reported, reconciling different existing phase diagrams. The magnetic moments of the Eu2+ ions are slightly canted, yielding a ferromagnetic contribution along the c direction that becomes stronger with pressure, until superconductivity sets in. The spin-density wave as well as the superconducting phase coexist with an antiferromagnetic interlayer coupling of the canted spins. Reducing the interlayer distance finally leads to a ferromagnetic Eu2+ interlayer coupling and to the suppression of superconductivity.

U.S. Forest Greenhouse Gas Impacts of a continued Expansion of E.U. Wood Pellet Demand

NASA Astrophysics Data System (ADS)

Latta, G.; Baker, J.; Ohrel, S. B.

2016-12-01

The United States has ambitious goals of greenhouse gas (GHG) reductions. A portion of these reductions are based on expected contributions from land use, land use change, and forestry (LULUCF). The European Union has similar goals which have resulted in a doubling of wood pellets exported from US ports destined for EU power plants over the last few years. There are potential conflicts between the GHG consequences of this pellet supply and the LULUCF contribution to US GHG goals. This study seeks to inform the discussion by modeling US forest GHG accounts using data measured on a grid of over 150,000 USDA Forest Service, Forest Inventory and Analysis (FIA) forestland plots across the conterminous United States. Empirical yield functions are estimate from plot log volume, biomass and carbon and provide the basis for changes in forest characteristics over time. Demand data based on a spatial database of over 2,000 forest product manufacturing facilities representing 11 intermediate and 13 final solid and pulpwood products. Manufacturing and logging costs are specific to slope, log size, and volume removed along with transportation costs based on fuel prices, FIA plot, and milling locations. The resulting partial spatial equilibrium model of the US forest sector is solved annually for the period 2010 - 2030 with demand shifted by energy prices and macroeconomic indicators from the US EIA's Annual Energy Outlook for a series of potential wood pellet export targets. For each wood pellet export level simulated, figures showing historic and scenario-specific forest products production are generated. Maps of the spatial allocation of both forest harvesting and carbon fluxes are presented at the National level and detail is given in both the US North and Southeast.

First-principles studies of Ce and Eu doped inorganic scintillator gamma ray detectors

NASA Astrophysics Data System (ADS)

Canning, Andrew; Chaudhry, Anurag; Boutchko, Rostyslav; Derenzo, Stephen

2011-03-01

We have performed DFT based band structure calculations for new Ce and Eu doped wide band gap inorganic materials to determine their potential as candidates for gamma ray scintillator detectors. These calculations are based on determining the 4f ground state level of the Ce and Eu relative to the valence band of the host as well as the position of the Ce and Eu 5d excited state relative to the conduction band of the host. Host hole and electron traps as well as STEs (self trapped excitons) can also limit the transfer of energy from the host to the Ce or Eu site and therefore limit the light output. We also present calculations for host hole traps and STEs to compare the energies to the Ce and Eu excited states. The work was supported by the U.S. Department of Homeland Security and carried out at the Lawrence Berkeley National Laboratory under U.S. Department of Energy Contract No. DE-AC02- 05CH11231.

The Enhanced Red Emission and Improved Thermal Stability of CaAlSiN3:Eu2+ Phosphors by Using Nano-EuB6 as Raw Material

PubMed Central

Liu, Wen-Quan; Wu, Dan; Chang, Hugejile; Duan, Ru-Xia; Wu, Wen-Jie; Amu, Guleng; Bao, Fu-Quan; Tegus, Ojiyed

2018-01-01

Synthesizing phosphors with high performance is still a necessary work for phosphor-converted white light-emitting diodes (W-LEDs). In this paper, three series of CaAlSiN3:Eu2+ (denoted as CASN:Eu2+) phosphors using Eu2O3, EuN and EuB6 as raw materials respectively are fabricated by under the alloy precursor normal pressure nitridation synthesis condition. We demonstrate that CASN:Eu2+ using nano-EuB6 as raw material shows higher emission intensity than others, which is ascribed to the increment of Eu2+ ionic content entering into the crystal lattice. An improved thermal stability can also be obtained by using nano-EuB6 due to the structurally stable status, which is assigned to the partial substitution of Eu–O (Eu–N) bonds by more covalent Eu–B ones that leads to a higher structural rigidity. In addition, the W-LEDs lamp was fabricated to explore its possible application in W-LEDs based on blue LEDs. Our results indicate that using EuB6 as raw materials can provide an effective way of enhancing the red emission and improving the thermal stability of the CASN:Eu2+ red phosphor. PMID:29370148

Luminescent properties of Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} and its potential application in white light emitting diodes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Zhijun, E-mail: wangzhijunmail@yahoo.com.cn; Li, Panlai; Li, Ting

2013-06-01

Graphical abstract: Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} phosphor can be effectively excited by an ultraviolet and near-ultraviolet light, and produce a bright blue emission centered at 436 nm. The CIE chromaticity coordinations (x, y) of Na{sub 2}CaSiO{sub 4}:Eu{sup 2+}(NSCE)/Li{sub 2}SrSiO{sub 4}:Eu{sup 2+}(LSSE) vary with the molar ratio of the two constituents. When NSCE/LSSE is 1:3, the CIE chromaticity coordination is (0.332, 0.346), which is close to that of the natural sunlight (0.33, 0.33). The results indicate that Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} may be a promising blue phosphor for UV chip-based multi-phosphor converted white light emitting diodes. Highlights: ► Na{sub 2}CaSiO{sub 4}:Eu{supmore » 2+} shows the blue emission with a peak at 436 nm and broad excitation band in the UV/n-UV range. ► White light with CIE coordinates (0.332, 0.346) is generated by mixing the blue phosphor with the Li{sub 2}SrSiO{sub 4}:Eu{sup 2+} yellow phosphor. ► Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} would be a promising blue phosphor candidate for UV chip-based multi-phosphor converted white LEDs. - Abstract: A novel blue phosphor Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} is synthesized by a high temperature solid-state reaction, and its luminescent properties are systematically studied. Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} can be effectively excited by the 354 nm radiation, and create blue emission (436 nm). The emission intensity of Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} is influenced by the Eu{sup 2+} doping content, and the optimal doping content is 1.5%, and the concentration quenching mechanism of Eu{sup 2+} in Na{sub 2}CaSiO{sub 4} can be attributed to the multipolar interaction. The white light with CIE coordinates (0.332, 0.346) is generated by mixing the blue phosphor Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} with the yellow phosphor Li{sub 2}SrSiO{sub 4}:Eu{sup 2+}. The results indicate that Na{sub 2}CaSiO{sub 4}:Eu{sup 2+} may be a potential blue emitting phosphor for UV chip-based multi-phosphor converted white light emitting diodes.« less

India-EU relations in health services: prospects and challenges

PubMed Central

2011-01-01

Background India and the EU are currently negotiating a Trade and Investment Agreement which also covers services. This paper examines the opportunities for and constraints to India-EU relations in health services in the context of this agreement, focusing on the EU as a market for India's health services exports and collaboration. The paper provides an overview of key features of health services in the EU and India and their bearing on bilateral relations in this sector. Methods Twenty six semi-structured, in-person, and telephonic interviews were conducted in 2007-2008 in four Indian cities. The respondents included management and practitioners in a variety of healthcare establishments, health sector representatives in Indian industry associations, health sector officials in the Indian government, and official representatives of selected EU countries and the European Commission based in New Delhi. Secondary sources were used to supplement and corroborate these findings. Results The interviews revealed that India-EU relations in health services are currently very limited. However, several opportunity segments exist, namely: (i) Telemedicine; (ii) Clinical trials and research in India for EU-based pharmaceutical companies; (iii) Medical transcriptions and back office support; (iv) Medical value travel; and (v) Collaborative ventures in medical education, research, training, staff deployment, and product development. However, various factors constrain India's exports to the EU. These include data protection regulations; recognition requirements; insurance portability restrictions; discriminatory conditions; and cultural, social, and perception-related barriers. The interviews also revealed several constraints in the Indian health care sector, including disparity in domestic standards and training, absence of clear guidelines and procedures, and inadequate infrastructure. Conclusions The paper concludes that although there are several promising areas for India-EU relations in health services, it will be difficult to realize these opportunities given the pre-dominance of public healthcare delivery in the EU and sensitivities associated with commercializing healthcare. Hence, a gradual approach based on pilot initiatives and selective collaboration would be advisable initially, which could be expanded once there is demonstrated evidence on outcomes. Overall, the paper makes a contribution to the social science and health literature by adding to the limited primary evidence base on globalization and health, especially from a developing-developed country and regional perspective. PMID:21310041

Charge compensation mechanisms in favor of the incorporation of the Eu3+ ion into the ZnO host lattice

NASA Astrophysics Data System (ADS)

Baira, M.; Bekhti-Siad, A.; Hebali, K.; Bouhani-Benziane, H.; Sahnoun, M.

2018-05-01

Eu3+ doped phosphors with charge compensation are potential candidates of red emitting phosphors for lamp applications. Charge compensation improves the luminescence performance of the material. The charge compensation can most probably be achieved by three possible mechanisms: (a) two Zn2+ ions are replaced by one Eu3+ ions and one monovalent cation, 2Zn2+ →Eu3++ Li+, where Li+ is acting as a charge compensator; (b) the charge compensation is provided by a zinc vacancy (VZn) defects, 3Zn2+ → 2Eu3++ VZn, the subscript Zn denotes an ion in a normal zinc site in the lattice; (c) two Zn2+ ions are replaced by one Eu3+ ions with the presence of interstitial oxygen (Oi), 2Zn2+ → 2Eu3++ Oi. Electronic structures of the crystals corresponding to the three models are evaluated by the first-principles quantum mechanical calculations based on the density functional theory. It is found that the charge compensator defects make Eu3+ doping in ZnO energetically more favorable. They break the local symmetry around the Eu3+ ion and lead to deep states below the empty upper band, the conduction band that could facilitate intra-4f shell transitions, which can obviously improve the emission intensity of Eu3+-doped ZnO. Therefore, the effect of these defects on the host crystals electronic band states relative to the Eu3+ states is reported, since both electron transfer and electronically energy transfer processes enhance the performance of optoelectronic devices based on this material. These theoretical insights are helpful for designing rare-earth doped oxide materials with high photoluminescence (PL) performance.

Pyrolytic synthesis and luminescence of porous lanthanide Eu-MOF.

PubMed

Jin, Guangya; Liu, Zhijian; Sun, Hongfa; Tian, Zhiyong

2016-02-01

A lanthanide metal coordination polymer [Eu2(BDC)3(DMSO)(H2O)] was synthesized by the reaction of europium oxide with benzene-1,3-dicarboxylic acid (H2BDC) in a mixed solution of dimethyl sulfoxide (DMSO) and water under hydrothermal conditions. The crystal structure of Eu2(BDC)3(DMSO)(H2O) was characterized by X-ray diffraction (XRD). Thermo-gravimetric analysis of Eu2(BDC)3(DMSO)(H2O) indicated that coordinated DMSO and H2O molecules could be removed to create Eu2(BDC)3(DMSO)(H2O)-py with permanent microporosity, which was also verified by powder XRD (PXRD) and elemental analysis. Both Eu2(BDC)3(DMSO)(H2O) and Eu2(BDC)3(DMSO)(H2O)-py showed mainly Eu-based luminescence and had characteristic emissions in the range 550-700 nm. Copyright © 2015 John Wiley & Sons, Ltd.

How Much Credence Does It Take? Evidence on the Trade-Off between Country-Of-Origin Information and Credence Attributes for Beef from a Choice Experiment in Sweden

PubMed Central

Hess, Sebastian; Johansson, Helena

2017-01-01

Based on a discrete choice experiment with 336 consumers, this study investigated whether the consumer propensity to choose a simplified European Union (EU) vs. non-EU denomination of origin for beef, instead of a specific country-of-origin (COO) denomination, depends upon the amount and type of credence information provided to the individual. The likelihood of choosing the EU/non-EU denomination of origin depended on the total number of other labelling credence attributes provided and also on the type of detailed credence attributes present in the choice. The presence of cues relating to animal welfare and far-reaching traceability had the highest likelihood of influencing the choice of the EU/non-EU denomination of origin. The compensatory qualities of each credence attribute in relation to the EU/non-EU origin denomination thus differed. PMID:28946674

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Zhang; Wanjun, Tang, E-mail: tangmailbox@126.com

Highlights: • Iso-structural garnet-type Na{sub 2}(Y,Eu)Mg{sub 2}V{sub 3}O{sub 12} solid solution were synthesized. • Efficient energy transfer from [VO{sub 4}]{sup 3−} to Eu{sup 3+} ions in this phosphor is observed obviously. • Tuning the Y/Eu ratio generates the varied hues from yellowish-green to reddish-orange. • This kind of phosphor can be potentially used in UV pumped LEDs. - Abstract: A series of solid-solution phosphors Na{sub 2}(Y,Eu)Mg{sub 2}V{sub 3}O{sub 12} were prepared using solution combustion reaction. X-ray diffraction studies verified the formation of single phase Na{sub 2}(Y,Eu)Mg{sub 2}V{sub 3}O{sub 12} with garnet structure. Na{sub 2}(Y,Eu)Mg{sub 2}V{sub 3}O{sub 12} phosphors show notmore » only a broad emission band with a maximum at 510 nm due to the [VO{sub 4}]{sup 3−} group but also several sharp emission lines due to the Eu{sup 3+} ions. The energy transfer from [VO{sub 4}]{sup 3−} to Eu{sup 3+} was discussed on the base of the spectral analysis. The color-tunable emissions of the Na{sub 2}(Y,Eu)Mg{sub 2}V{sub 3}O{sub 12} phosphor as a function of Y/Eu ratio are realized by continuously generating the varied hues from yellowish-green to reddish-orange. This indicates that the obtained phosphor may have potential applications in the field of UV-based white LEDs.« less

Quantitative study of energy-transfer mechanism in Eu,O-codoped GaN by time-resolved photoluminescence spectroscopy

NASA Astrophysics Data System (ADS)

Inaba, Tomohiro; Kojima, Takanori; Yamashita, Genki; Matsubara, Eiichi; Mitchell, Brandon; Miyagawa, Reina; Eryu, Osamu; Tatebayashi, Jun; Ashida, Masaaki; Fujiwara, Yasufumi

2018-04-01

In order to investigate the excitation processes in Eu,O-codoped GaN (GaN:Eu,O), the time-resolved photoluminescence signal including the rising part is analyzed. A rate equation is developed based upon a model for the excitation processes in GaN:Eu to fit the experimental data. The non-radiative recombination rate of the trap state in the GaN host, the energy transfer rate between the Eu3+ ions and the GaN host, the radiative transition probability of Eu3+ ion, as well as the ratio of the number of luminescent sites (OMVPE 4α and OMVPE 4β), are simultaneously determined. It is revealed and quantified that radiative transition probability of the Eu ion is the bottleneck for the enhancement of light output from GaN:Eu. We also evaluate the effect of the growth conditions on the luminescent efficiency of GaN:Eu quantitatively, and find the correlation between emission intensity of GaN:Eu and the fitting parameters introduced in our model.

Preparation and photoluminescence properties of functionalized silica materials incorporating europium complexes

NASA Astrophysics Data System (ADS)

Lourenço, A. V. S.; Kodaira, C. A.; Souza, E. R.; Felinto, M. C. F. C.; Malta, O. L.; Brito, H. F.

2011-08-01

In the present work, the surface of the Eu-BTC = [Eu(EMA)(H 2O) 2], [Eu(TLA)(H 2O) 4] and [Eu(TMA)(H 2O) 6] complexes (EMA = 1,2,3-benzenetricarboxylate, TLA = 1,2,4-benzenetricarboxylate and TMA = 1,3,5-benzenetricarboxylate) was modified using 3-aminopropyltriethoxysilane (APTES) by a new microwave assisted method that proved to be simple and efficient. According to our observations, the most efficient luminescence is the material based on APTES incorporating [Eu(TMA)(H 2O) 6] complexes, denoted as Eu-TMA-Si, shows the highest emission efficiency. Therefore, it is proposed as a promising material for molecular conjugation in clinical diagnosis.

Synthesis, Characterization, and Handling of Eu(II)-Containing Complexes for Molecular Imaging Applications

NASA Astrophysics Data System (ADS)

Basal, Lina A.; Allen, Matthew J.

2018-03-01

Considerable research effort has focused on the in vivo use of responsive imaging probes that change imaging properties upon reacting with oxygen because hypoxia is relevant to diagnosing, treating, and monitoring diseases. One promising class of compounds for oxygen-responsive imaging is Eu(II)-containing complexes because the Eu(II/III) redox couple enables imaging with multiple modalities including magnetic resonance and photoacoustic imaging. The use of Eu(II) requires care in handling to avoid unintended oxidation during synthesis and characterization. This review describes recent advances in the field of imaging agents based on discrete Eu(II)-containing complexes with specific focus on the synthesis, characterization, and handling of aqueous Eu(II)-containing complexes.

Structure and Properties of Melt-spun Bio-based Polyamide/Eu(TTA)3Phen Composite fibers

NASA Astrophysics Data System (ADS)

Li, Yunye; Lou, Pengfei; Jia, Qingxiu

2018-02-01

In this paper, the bio-based polyamide (PA ) was melt polymerized from four bio-based monomers. Composites of the bio-based PA and europium complex Eu(TTA)3Phen were prepared through solution mixing using N, N-Dimethylformamide (DMF) and formic acid as the mixed solvent, and then composite fibers were obtained by melt spinning method. The structure and properties of the melt-spun composite fibers were characterized by FTIR and SEM. The results indicated that the Eu(TTA)3Phen complex, with the average diameter below 300 nm, was homogeneously dispersed in the PA matrix. FTIR spectra indicated that the coordination bond between carbonyl of BDIS and Eu(TTA)3Phen complex formed, which was also confirmed by the mechanical properties. The initial modulus and breaking strength of these fibers can arrived at 2.5GPa and 0.3GPa, respectively.

Higher thermoelectric performance of Zintl phases (Eu0.5Yb0.5)1-xCaxMg2Bi2 by band engineering and strain fluctuation.

PubMed

Shuai, Jing; Geng, Huiyuan; Lan, Yucheng; Zhu, Zhuan; Wang, Chao; Liu, Zihang; Bao, Jiming; Chu, Ching-Wu; Sui, Jiehe; Ren, Zhifeng

2016-07-19

Complex Zintl phases, especially antimony (Sb)-based YbZn0.4Cd1.6Sb2 with figure-of-merit (ZT) of ∼1.2 at 700 K, are good candidates as thermoelectric materials because of their intrinsic "electron-crystal, phonon-glass" nature. Here, we report the rarely studied p-type bismuth (Bi)-based Zintl phases (Ca,Yb,Eu)Mg2Bi2 with a record thermoelectric performance. Phase-pure EuMg2Bi2 is successfully prepared with suppressed bipolar effect to reach ZT ∼ 1. Further partial substitution of Eu by Ca and Yb enhanced ZT to ∼1.3 for Eu0.2Yb0.2Ca0.6Mg2Bi2 at 873 K. Density-functional theory (DFT) simulation indicates the alloying has no effect on the valence band, but does affect the conduction band. Such band engineering results in good p-type thermoelectric properties with high carrier mobility. Using transmission electron microscopy, various types of strains are observed and are believed to be due to atomic mass and size fluctuations. Point defects, strain, dislocations, and nanostructures jointly contribute to phonon scattering, confirmed by the semiclassical theoretical calculations based on a modified Debye-Callaway model of lattice thermal conductivity. This work indicates Bi-based (Ca,Yb,Eu)Mg2Bi2 is better than the Sb-based Zintl phases.

Development of a novel europium complex-based luminescent probe for time-gated luminescence imaging of hypochlorous acid in living samples

NASA Astrophysics Data System (ADS)

Liu, Xiangli; Guo, Lianying; Song, Bo; Tang, Zhixin; Yuan, Jingli

2017-03-01

Luminescent lanthanide complexes are key reagents used in the time-gated luminescence bioassay technique, but functional lanthanide complexes that can act as luminescent probes for specifically responding to analytes are very limited. In this work, we designed and synthesized a novel Eu3+ complex-based luminescence probe for hypochlorous acid (HOCl), NPPTTA-Eu3+, by using terpyridine polyacid-Eu3+, dinitrophenyl, and hydrazine as luminophore, quencher and HOCl-recognizer moieties, respectively. In the absence of HOCl, the probe is non-luminescent due to the strong luminescence quenching of the dinitrophenyl group in the complex. However, upon reaction with HOCl, the dinitrophenyl moiety is rapidly cleaved from the probe, which affords a strongly luminescent Eu3+ complex CPTTA-Eu3+, accompanied by a ˜900-fold luminescence enhancement with a long luminescence lifetime of 1.41 ms. This unique luminescence response of NPPTTA-Eu3+ to HOCl allowed NPPTTA-Eu3+ to be conveniently used as a probe for highly selective and sensitive detection of HOCl under the time-gated luminescence mode. In addition, by loading NPPTTA-Eu3+ into RAW 264.7 macrophage cells and Daphnia magna, the generation of endogenous HOCl in RAW 264.7 cells and the uptake of exogenous HOCl by Daphnia magna were successfully imaged on a true-color time-gated luminescence microscope. The results demonstrated the practical applicability of NPPTTA-Eu3+ as an efficient probe for time-gated luminescence imaging of HOCl in living cells and organisms.

Ternary complex formation of Eu(III) with o-phthalate in aqueous solutions.

PubMed

Park, K K; Jung, E C; Cho, H-R; Kim, W H

2009-08-15

Ternary hydroxo complex formation of Eu(III) with o-phthalate was investigated by potentiometry and fluorescence spectrophotometry. Curves of the equilibrium pH versus the amount of NaOH added showed that the pH value starting to form a Eu(III) precipitate was decreased due to the formation of a ternary hydroxo complex, EuOHL(s) (L = phthalate). The formation of EuOHL(s) was qualitatively confirmed by the enhancement of the fluorescence intensity of Eu(III) in the precipitate with the light absorbed by phthalate, and was quantitatively confirmed by the measurement of the amounts of Eu(III), OH(-) and phthalate included in the precipitate. The solubility product of EuOHL(s) was determined as pK(sp)(0) = 15.6+/-0.4. Characteristic features in the fluorescence spectra and the solubility product of the Eu(III)-phthalate complex were compared with those of the Eu(III)-PDA (PDA = pyridine-2,6-dicarboxylate) complex. The fluorescence intensity of the EuL(+) complex of L = PDA was about 11 times stronger than that of L = phthalate. The origin of the difference in the fluorescence intensity is discussed based on the intramolecular energy transfer effect from the lowest triplet energy level of the ligand to the resonance energy level of Eu(III).

Climate Change Adaptation Practices in Various Countries

NASA Astrophysics Data System (ADS)

Tanik, A.; Tekten, D.

2017-08-01

The paper will be a review work on the recent strategies of EU in general, and will underline the inspected sectoral based adaptation practices and action plans of 7 countries; namely Germany, France, Spain, Italy, Denmark, USA and Kenya from Africa continent. Although every countries’ action plan have some similarities on sectoral analysis, each country in accordance with the specific nature of the problem seems to create its own sectoral analysis. Within this context, green and white documents of EU adaptation to climate change, EU strategy on climate change, EU targets of 2020 on climate change and EU adaptation support tools are investigated.

Combining machine learning and ontological data handling for multi-source classification of nature conservation areas

NASA Astrophysics Data System (ADS)

Moran, Niklas; Nieland, Simon; Tintrup gen. Suntrup, Gregor; Kleinschmit, Birgit

2017-02-01

Manual field surveys for nature conservation management are expensive and time-consuming and could be supplemented and streamlined by using Remote Sensing (RS). RS is critical to meet requirements of existing laws such as the EU Habitats Directive (HabDir) and more importantly to meet future challenges. The full potential of RS has yet to be harnessed as different nomenclatures and procedures hinder interoperability, comparison and provenance. Therefore, automated tools are needed to use RS data to produce comparable, empirical data outputs that lend themselves to data discovery and provenance. These issues are addressed by a novel, semi-automatic ontology-based classification method that uses machine learning algorithms and Web Ontology Language (OWL) ontologies that yields traceable, interoperable and observation-based classification outputs. The method was tested on European Union Nature Information System (EUNIS) grasslands in Rheinland-Palatinate, Germany. The developed methodology is a first step in developing observation-based ontologies in the field of nature conservation. The tests show promising results for the determination of the grassland indicators wetness and alkalinity with an overall accuracy of 85% for alkalinity and 76% for wetness.

The public health effect of economic crises and alternative policy responses in Europe: an empirical analysis.

PubMed

Stuckler, David; Basu, Sanjay; Suhrcke, Marc; Coutts, Adam; McKee, Martin

2009-07-25

There is widespread concern that the present economic crisis, particularly its effect on unemployment, will adversely affect population health. We investigated how economic changes have affected mortality rates over the past three decades and identified how governments might reduce adverse effects. We used multivariate regression, correcting for population ageing, past mortality and employment trends, and country-specific differences in health-care infrastructure, to examine associations between changes in employment and mortality, and how associations were modified by different types of government expenditure for 26 European Union (EU) countries between 1970 and 2007. We noted that every 1% increase in unemployment was associated with a 0.79% rise in suicides at ages younger than 65 years (95% CI 0.16-1.42; 60-550 potential excess deaths [mean 310] EU-wide), although the effect size was non-significant at all ages (0.49%, -0.04 to 1.02), and with a 0.79% rise in homicides (95% CI 0.06-1.52; 3-80 potential excess deaths [mean 40] EU-wide). By contrast, road-traffic deaths decreased by 1.39% (0.64-2.14; 290-980 potential fewer deaths [mean 630] EU-wide). A more than 3% increase in unemployment had a greater effect on suicides at ages younger than 65 years (4.45%, 95% CI 0.65-8.24; 250-3220 potential excess deaths [mean 1740] EU-wide) and deaths from alcohol abuse (28.0%, 12.30-43.70; 1550-5490 potential excess deaths [mean 3500] EU-wide). We noted no consistent evidence across the EU that all-cause mortality rates increased when unemployment rose, although populations varied substantially in how sensitive mortality was to economic crises, depending partly on differences in social protection. Every US$10 per person increased investment in active labour market programmes reduced the effect of unemployment on suicides by 0.038% (95% CI -0.004 to -0.071). Rises in unemployment are associated with significant short-term increases in premature deaths from intentional violence, while reducing traffic fatalities. Active labour market programmes that keep and reintegrate workers in jobs could mitigate some adverse health effects of economic downturns. Centre for Crime and Justice Studies, King's College, London, UK; and Wates Foundation (UK).

Electronic structure of the iron-based superconductor (La,Eu)FeAsO1-xFx investigated by laser photoemission spectroscopy

NASA Astrophysics Data System (ADS)

Malaeb, Walid; Awad, Ramadan; Hibino, Taku; Kamihara, Yoichi; Kondo, Takeshi; Shin, Shik

2018-05-01

We have implemented laser photoemission spectroscopy (PES) to investigate the electronic structure of the iron-based superconductor (La,Eu)FeAsO1-xFx (LaEu1111) which is an interesting compound in the "1111" family showing a high value of the superconducting (SC) transition temperature (Tc) due to Eu doping. At least two energy scales were observed from the PES data in the SC compound: One at ∼14 meV closing around Tc and thus corresponding to the SC gap. Another energy scale appears at ∼35 meV and survives at temperatures above Tc which represents the pseudogap (PG). The non-SC sample (La,Eu)FeAsO shows a PG at ∼ 41 meV. These observations in this new superconductor are consistent with the general trend followed by other compounds in the "1111" family.

Modelling of underwater light fields in turbid and eutrophic waters: application and validation with experimental data

NASA Astrophysics Data System (ADS)

Sundarabalan, B.; Shanmugam, P.

2014-09-01

A reliable radiative transfer model is an essential and indispensable tool for understanding of the radiative transfer processes in homogenous and layered waters, analyzing measurements made by radiance sensors and developing remote sensing algorithms to derive meaningful physical quantities and biogeochemical variables in turbid and productive coastal waters. Existing radiative transfer models have been designed to be applicable to either homogenous waters or inhomogeneous waters. To overcome such constraints associated with these models, this study presents a radiative transfer model that treats a homogenous layer as a diffuse part and an inhomogeneous layer as a direct part in the water column and combines these two parts appropriately in order to generate more reliable underwater light field data such as upwelling radiance (Lu), downwelling irradiance (Ed) and upwelling irradiance (Eu). The diffuse model assumes the inherent optical properties (IOPs) to be vertically continuous and the light fields to exponentially decrease with the depth, whereas the direct part considers the water column to be vertically inhomogeneous (layer-by-layer phenomena) with the vertically varying phase function. The surface and bottom boundary conditions, source function due to chlorophyll and solar incident geometry are also included in the present RT model. The performance of this model is assessed in a variety of waters (clear, turbid and eutrophic) using the measured radiometric data. The present model shows an advantage in terms of producing accurate Lu, Ed and Eu profiles (in spatial domain) in different waters determined by both homogenous and inhomogeneous conditions. The feasibility of predicting these underwater light fields based on the remotely estimated IOP data is also examined using the present RT model. For this application, vertical profiles of the water constituents and IOPs are estimated by empirical models based on our in-situ data. The present RT model generates Lu, Ed and Eu spectra closely consistent with the measured data. These results lead to a conclusion that the present RT model is a viable alternative to existing RT models and has an important implication for remote sensing of optically complex waters.

Modelling of underwater light fields in turbid and eutrophic waters: application and validation with experimental data

NASA Astrophysics Data System (ADS)

Sundarabalan, B.; Shanmugam, P.

2015-01-01

A reliable radiative transfer (RT) model is an essential and indispensable tool for understanding the radiative transfer processes in homogenous and layered waters, analyzing measurements made by radiance sensors and developing remote-sensing algorithms to derive meaningful physical quantities and biogeochemical variables in turbid and productive coastal waters. Existing radiative transfer models have been designed to be applicable to either homogenous waters or inhomogeneous waters. To overcome such constraints associated with these models, this study presents a radiative transfer model that treats a homogenous layer as a diffuse part and an inhomogeneous layer as a direct part in the water column and combines these two parts appropriately in order to generate more reliable underwater light-field data such as upwelling radiance (Lu), downwelling irradiance (Ed) and upwelling irradiance (Eu). The diffuse model assumes the inherent optical properties (IOPs) to be vertically continuous and the light fields to exponentially decrease with depth, whereas the direct part considers the water column to be vertically inhomogeneous (layer-by-layer phenomena) with the vertically varying phase function. The surface and bottom boundary conditions, source function due to chlorophyll and solar incident geometry are also included in the present RT model. The performance of this model is assessed in a variety of waters (clear, turbid and eutrophic) using the measured radiometric data. The present model shows an advantage in terms of producing accurate Lu, Ed and Eu profiles (in spatial domain) in different waters determined by both homogenous and inhomogeneous conditions. The feasibility of predicting these underwater light fields based on the remotely estimated IOP data is also examined using the present RT model. For this application, vertical profiles of the water constituents and IOPs are estimated by empirical models based on our in situ data. The present RT model generates Lu, Ed and Eu spectra closely consistent with the measured data. These results lead to a conclusion that the present RT model is a viable alternative to existing RT models and has an important implication for remote sensing of optically complex waters.

Exploring the mutual enhancement between droughts and heatwaves in Europe

NASA Astrophysics Data System (ADS)

Samaniego, L. E.; Kumar, R.; Thober, S.; Pan, M.; Prudhomme, C.; Sheffield, J.; Wanders, N.; Wood, E. F.

2016-12-01

Extensive analyses of past and future changes in essential hydrologicalvariables such as soil moisture based on climate and/or land surfacemodel projections have been carried out during the last decades. Recentstudies, however, showed that no comprehensive picture of theanticipated changes has evolved basically due to the large uncertaintiesin both observed and projected changes as well as their coarser spatialresolution. So far, concluding statements cannot be drawn, in particularfor droughts and heat waves, although the key role of soil moisture foramplifying heat waves and its skill for predicting temperature has beenidentified. In this study, we hypothesized that the mutual enhancementbetween droughts and heat waves is intensified as the climate warms. Putdifferently, a drought can make a hot day hotter while a heat wave canexacerbate a moderate drought event into an extreme one. Europe, in particular, has endured large scale drought-heat-wave eventsduring the recent past (e.g., 2003), which have induced enormoussocio-economic losses as well as casualties. Testing thepreviously posed hypothesis within the Pan-EU domain has been limitedmainly by the availability of reliable and high-resolution data sets. The EDgE project commissioned by the ECMWF (C3S) provides a uniqueopportunity to test this hypothesis. High-resolution multi-modelhydrologic simulations over the Pan-EU domain at a scale of 5x5 km2 havebeen completed for the historical period 1955-2015 with the mHM(www.ufz.de/mhm) and PCR-GLOBWB. Noah-MP and VIC simulations will beaccomplished soon. Using these multi-model unprecedented simulations, daily soil moistureindex and temperature anomalies from 1955 to 2015 will beestimated. The stochastic relationships between these variables will beinvestigated with empirical copulas. The main goal of this study is totest whether a significant Granger causality existsbetween soil moisture and temperature anomaly fields over thePan-EU. The advantage of this testing framework stems from the fact thatit is based on predictability instead of correlation to identifycausation, as it is the case with standard correlation-basedapproaches. Preliminary tests indicate that the mutual enhancementhypothesis cannot be rejected in hot-spot areas enduring heavyanthropogenic disturbances.

The new Zintl phases Eu{sub 21}Cd{sub 4}Sb{sub 18} and Eu{sub 21}Mn{sub 4}Sb{sub 18}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Yi; Darone, Gregory M.; Bobev, Svilen, E-mail: bobev@udel.edu

Crystals of two new Zintl compounds, Eu{sub 21}Mn{sub 4}Sb{sub 18} and Eu{sub 21}Cd{sub 4}Sb{sub 18} have been synthesized using the molten metal flux method, and their structures have been established by single-crystal X-ray diffraction. Both compounds are isotypic and crystallize in the monoclinic space group C2/m (No. 12, Z=4). The structures are based on edge- and corner-shared MnSb{sub 4} or CdSb{sub 4} tetrahedra, which make octameric [Mn{sub 8}Sb{sub 22}] or [Cd{sub 8}Sb{sub 22}] polyanions. Homoatomic Sb–Sb bonds are present in both structures. The Eu atoms take the role of Eu{sup 2+}cations with seven unpaired 4f electrons, as suggested by themore » temperature-dependent magnetization measurements. The magnetic susceptibilities of Eu{sub 21}Mn{sub 4}Sb{sub 18} and Eu{sub 21}Cd{sub 4}Sb{sub 18} indicate that both phases order anti-ferromagnetically with Néel temperatures of ca. 7 K and ca. 10 K, respectively. The unpaired 3d electrons of the Mn atoms in Eu{sub 21}Mn{sub 4}Sb{sub 18} do contribute to the magnetic response, however, the bulk magnetization measurements do not provide evidence for long-range ordering of the Mn spins down to 5 K. Electrical resistivity measurements suggest that both compounds are narrow band gap semiconductors. - Graphical abstract: Eu{sub 21}Mn{sub 4}Sb{sub 18} and Eu{sub 21}Cd{sub 4}Sb{sub 18} have complex monoclinic structures, based on MnSb{sub 4} and CdSb{sub 4} tetrahedra, both edge- and corner-shared. A perspective of the crystal structure is shown, as viewed along the b axis. Display Omitted - Highlights: • Eu{sub 21}Mn{sub 4}Sb{sub 18} and Eu{sub 21}Cd{sub 4}Sb{sub 18} are novel compounds in the respective ternary phase diagrams. • For both structures, the Zintl-Klemm rules are followed, and both are small gap semiconductors. • Eu{sub 21}Mn{sub 4}Sb{sub 18} and Eu{sub 21}Cd{sub 4}Sb{sub 18} are air-stable Zintl phases and could be new thermoelectric materials.« less

The New Mode of Energy Transferring between Mn2+ and Eu2+ in Nitride Based Phosphor SrAlSi4N7 with Tunable Light and Excellent Thermal Stability.

PubMed

Ding, Jianyan; Seto, Takatoshi; Wang, Yichao; Cao, Yaxin; Li, Hua; Wang, YuHua

2018-06-19

In this work, energy transfers reciprocally between Mn2+ and Eu2+ ions in nitride SrAlSi4N7 have been found and investigated in detailed. In contrast to Mn2+ and Eu2+ activated oxide based phosphors, the red light centering at 608 nm is ascribed to 4f-5d transitions of Eu2+ ions and Mn2+ activated SrAlSi4N7 emits a cyan light peaked at 500 nm. Additionally, the special broad excitation band of SrAlSi4N7: Mn2+ centering at 362 nm has been covered by that of Eu2+ ions ranging from 300 to 550 nm. The overlap of energy level of Mn2+ and Eu2+ ions creates the condition for the energy transferring reciprocally between Eu2+ and Mn2+ ions. A series of SrAlSi4N7: 0.002Mn2+, xEu2+ (0 ≤x≤ 005) with tunable emission light have been synthesized and the decay curves of samples prove the happening of the energy transfer between Mn2+ and Eu2+ ions reciprocally. This mode of energy transfer not only prevents the loss of energy, but also improves the thermal stability and the intensity of SrAlSi4N7: Mn2+, Eu2+ at 150 °C is still beyond 92 % of the initial intensity. The results provide a new mode of energy transfer, which is expected to improve the drawback existing in energy transfer. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Advertising of medical devices: foreign experience and Ukrainian practice.

PubMed

Pashkov, Vitalii; Harkusha, Andrii; Bytiak, Oleksii

Chosen European foreign policy vector for Ukraine establishes its obligation to enforce the process of adaptation of the EU law regulations in the internal legal policy. The approximation of Ukrainian law to the European Union (EU) "acquis communautaire" is not only the instrument for deepening our economic cooperation with the European Union, but also the important measure to enhance further development of Ukraine in general. National legislation, which regulate advertising and promotion of medical devices (MD), is not an exception. Some key points on legal regulation of abovementioned sphere is a base of this study. Ukrainian legislation, European Union`s Law Acts, EU's member-states law, WHO Acts and Recommendations, European Medical Technology Industry Association (EUCOMED) Acts. Article is based on dialectical, comparative, analytic, synthetic and comprehensive research methods. In accordance with Ukrainian legislation, there is no special law that concerns advertising on MD in Ukraine, this sphere is regulated by general law that named ≪About advertisement≫, but it doesn't take into account even main characteristics of such a special object as medical devices (MD). Moreover, the law ≪About advertisement≫ contain discrepancies in terms that are used, these contradictions, in our opinion, must be eliminated by appropriate law reforms. The advertising and promotion of MD in EU is regulated by a combination of EU and national legislation of EU Member States, national advertising and promotion of MD are not harmonized with the EU MDD for now, resulting in a fragmented legal landscape that differs from one EU Member State to the other. Practice of adopting different codes and guides that regulate advertising, including advertising of MD, is widespread in EU and EU Member States and thus must be used in Ukraine with appropriate reformation of national law.

Proposed re-evaluation of the 154Eu thermal ( n, γ) capture cross-section based on spent fuel benchmarking studies

DOE PAGES

Skutnik, Steven E.

2016-09-22

154Eu is a nuclide of considerable importance to both non-destructive measurements of used nuclear fuel assembly burnup as well as for calculating the radiation source term for used fuel storage and transportation. But, recent evidence from code validation studies of spent fuel benchmarks have revealed evidence of a systemic bias in predicted 154Eu inventories when using ENDF/B-VII.0 and ENDF/B-VII.1 nuclear data libraries, wherein Eu-154 is consistently over-predicted on the order of 10% or more. Further, this bias is found to correlate with sample burnup, resulting in a larger departure from experimental measurements for higher sample burnups. Here, the bias in Eu-154 is characterized across eleven spent fuel destructive assay benchmarks from five different assemblies. Based on these studies, possible amendments to the ENDF/B-VII.0 and VII.1 evaluations of the 154Eu (n,γ) 155Eu are explored. By amending the location of the first resolved resonance for the 154Eu radiative capture cross-section (centered at 0.195 eV in ENDF/B-VII.0 and VII.1) to 0.188 eV and adjusting the neutron capture width proportional tomore » $$\\sqrt1/E$$, the amended cross-section evaluation was found to reduce the bias in predicted 154Eu inventories by approximately 5–7%. And while the amended capture cross-section still results in a residual over-prediction of 154Eu (ranging from 2% to 9%), the effect is substantially attenuated compared with the nominal ENDF/B-VII.0 and VII.1 evaluations.« less

Proposed re-evaluation of the 154Eu thermal ( n, γ) capture cross-section based on spent fuel benchmarking studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Skutnik, Steven E.

154Eu is a nuclide of considerable importance to both non-destructive measurements of used nuclear fuel assembly burnup as well as for calculating the radiation source term for used fuel storage and transportation. But, recent evidence from code validation studies of spent fuel benchmarks have revealed evidence of a systemic bias in predicted 154Eu inventories when using ENDF/B-VII.0 and ENDF/B-VII.1 nuclear data libraries, wherein Eu-154 is consistently over-predicted on the order of 10% or more. Further, this bias is found to correlate with sample burnup, resulting in a larger departure from experimental measurements for higher sample burnups. Here, the bias in Eu-154 is characterized across eleven spent fuel destructive assay benchmarks from five different assemblies. Based on these studies, possible amendments to the ENDF/B-VII.0 and VII.1 evaluations of the 154Eu (n,γ) 155Eu are explored. By amending the location of the first resolved resonance for the 154Eu radiative capture cross-section (centered at 0.195 eV in ENDF/B-VII.0 and VII.1) to 0.188 eV and adjusting the neutron capture width proportional tomore » $$\\sqrt1/E$$, the amended cross-section evaluation was found to reduce the bias in predicted 154Eu inventories by approximately 5–7%. And while the amended capture cross-section still results in a residual over-prediction of 154Eu (ranging from 2% to 9%), the effect is substantially attenuated compared with the nominal ENDF/B-VII.0 and VII.1 evaluations.« less

Synthesis and luminescence properties of polymer-rare earth complexes containing salicylaldehyde-type bidentate Schiff base ligand.

PubMed

Zhang, Dandan; Gao, Baojiao; Li, Yanbin

2017-08-01

Using molecular design and polymer reactions, two types of bidentate Schiff base ligands, salicylaldehyde-aniline (SAN) and salicylaldehyde-cyclohexylamine (SCA), were synchronously synthesized and bonded onto the side chain of polysulfone (PSF), giving two bidentate Schiff base ligand-functionalized PSFs, PSF-SAN and PSF-SCA, referred to as macromolecular ligands. Following coordination reactions between the macromolecular ligands and Eu(III) and Tb(III) ions (the reaction occurred between the bonded ligands SAN or SCA and the lanthanide ion), two series of luminescent polymer-rare earth complexes, PSF-SAN-Eu(III) and PSF-SCA-Tb(III), were obtained. The two macromolecular ligands were fully characterized by Fourier transform infrared (FTIR), 1 H NMR and UV absorption spectroscopy, and the prepared complexes were also characterized by FTIR, UV absorption spectroscopy and thermo-gravity analysis. On this basis, the photoluminescence properties of these complexes and the relationships between their structure and luminescence were investigated in depth. The results show that the bonded bidentate Schiff base ligands, SAN and SCA, can effectively sensitize the fluorescence emission of Eu(III) and Tb(III) ions, respectively. PSF-SAN-Eu(III) series complexes, namely the binary complex PSF-(SAN) 3 -Eu(III) and the ternary complex PSF-(SAN) 3 -Eu(III)-(Phen) 1 (Phen is the small-molecule ligand 1,10-phenanthroline), produce strong red luminescence, suggesting that the triplet state energy level of SAN is lower and well matched with the resonant energy level of the Eu(III) ion. By contrast, PSF-SAN-Eu(III) series complexes, namely the binary complex PSF-(SCA) 3 -Tb(III) and the ternary complex PSF-(SCA) 3 -Tb(III)-(Phen) 1 , display strong green luminescence, suggesting that the triplet state energy level of SCA is higher and is well matched with the resonant energy level of Tb(III). Copyright © 2017 John Wiley & Sons, Ltd.

High-brightness and high-color purity red-emitting Ca3Lu(AlO)3(BO3)4:Eu3+ phosphors with internal quantum efficiency close to unity for near-ultraviolet-based white-light-emitting diodes.

PubMed

Huang, Xiaoyong; Wang, Shaoying; Li, Bin; Sun, Qi; Guo, Heng

2018-03-15

In this work, we reported on high-brightness Eu 3+ -activated Ca 3 Lu(AlO) 3 (BO 3 ) 4 (CLAB) red-emitting phosphors. Under 397 nm excitation, the CLAB:Eu 3+ phosphors showed intense red emissions at around 621 nm with CIE coordinates of (0.657, 0.343). The optimal doping concentration of Eu 3+ ions was found to be 30 mol. %, and the CLAB:0.3Eu 3+ sample possessed high-color purity of 93% and ultra-high internal quantum efficiency as great as 98.5%. Importantly, the CLAB:0.3Eu 3+ also had good thermal stability. Finally, a white-light-emitting diode (WLED) lamp with good color-rendering index was fabricated by using a 365 nm ultraviolet chip and the phosphor blends of CLAB:0.3Eu 3+ red-emitting phosphors, (Ba,Sr) 2 SiO 4 :Eu 2+ green-emitting phosphors, and BaMgAl 10 O 7 :Eu 2+ blue-emitting phosphors.

NO-assisted molecular-beam epitaxial growth of nitrogen substituted EuO

NASA Astrophysics Data System (ADS)

Wicks, R.; Altendorf, S. G.; Caspers, C.; Kierspel, H.; Sutarto, R.; Tjeng, L. H.; Damascelli, A.

2012-04-01

We have investigated a method for substituting oxygen with nitrogen in EuO thin films, which is based on molecular beam epitaxy distillation with NO gas as the oxidizer. By varying the NO gas pressure, we produce crystalline, epitaxial EuO1 -xNx films with good control over the films' nitrogen concentration. In situ x-ray photoemission spectroscopy reveals that nitrogen substitution is connected to the formation Eu3+4f6 and a corresponding decrease in the number of Eu2+4f7, indicating that nitrogen is being incorporated in its 3- oxidation state. While small amounts of Eu3+ in over-oxidized Eu1-δO thin films lead to a drastic suppression of the ferromagnetism, the formation of Eu3+ in EuO1-xNx still allows the ferromagnetic phase to exist with an unaffected Tc, thus providing an ideal model system to study the interplay between the magnetic f7 (J = 7/2) and the non-magnetic f6 (J = 0) states close to the Fermi level.

Triple energy transfer and color tuning in Tb3+ and Eu3+-coactivated apatite-type gadolinium-containing phosphors

NASA Astrophysics Data System (ADS)

Guo, Ning; Liang, Qimeng; Li, Shuo; Ouyang, Ruizhuo; Lü, Wei

2017-11-01

A family of apatite-type fluorophosphate phosphors with general formula Sr3Gd(1-m-n)Na(PO4)3F:mTb3+,nEu3+ (SGN:mTb3+,nEu3+) have been synthesized via the high-temperature solid-state reaction method. Triple energy transfer processes from Gd3+ in the host to both Tb3+ and Eu3+, as well as from Tb3+ to Eu3+ have been verified by the photoluminescence spectra. Under the excitation of UV light, both green line from the transitions of Tb3+ and red line origin from the transitions of Eu3+ have been simultaneously observed in a single phase phosphor, which makes a promise for tunable color emissions from yellowish-green through yellow and ultimately to reddish-orange by simply adjusting the Eu3+ content (n) in SGN:0.20Tb3+,nEu3+ phosphors. Additionally, the energy transfer from the Tb3+ to the Eu3+ ions has been demonstrated to be a resonant type via a quadrupole-quadrupole mechanism based on the Dexter's theoretical model, and the energy transfer efficiency increases with an increase in Eu3+ concentration.

History and current status of strontium iodide scintillators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cherepy, Nerine J.; Beck, Patrick R.; Payne, Stephen A.

Eu-doped strontium iodide single crystal growth has reached maturity and prototype SrI 2(Eu)-based gamma ray spectrometers provide detection performance advantages over standard detectors. SrI 2(Eu) offers a high, proportional light yield of >80,000 photons/MeV. Energy resolution of <3% at 662 keV with 1.5” x 1.5” SrI2(Eu) crystals is routinely achieved, by employing either a small taper at the top of the crystal or a digital readout technique. These methods overcome light-trapping, in which scintillation light is re-absorbed and re-emitted in Eu 2+-doped crystals. As a result, its excellent energy resolution, lack of intrinsic radioactivity or toxicity, and commercial availability makemore » SrI 2(Eu) the ideal scintillator for use in handheld radioisotope identification devices. A 6-lb SrI 2(Eu) radioisotope identifier is described.« less

History and current status of strontium iodide scintillators

DOE PAGES

Cherepy, Nerine J.; Beck, Patrick R.; Payne, Stephen A.; ...

2017-09-15

Eu-doped strontium iodide single crystal growth has reached maturity and prototype SrI 2(Eu)-based gamma ray spectrometers provide detection performance advantages over standard detectors. SrI 2(Eu) offers a high, proportional light yield of >80,000 photons/MeV. Energy resolution of <3% at 662 keV with 1.5” x 1.5” SrI2(Eu) crystals is routinely achieved, by employing either a small taper at the top of the crystal or a digital readout technique. These methods overcome light-trapping, in which scintillation light is re-absorbed and re-emitted in Eu 2+-doped crystals. As a result, its excellent energy resolution, lack of intrinsic radioactivity or toxicity, and commercial availability makemore » SrI 2(Eu) the ideal scintillator for use in handheld radioisotope identification devices. A 6-lb SrI 2(Eu) radioisotope identifier is described.« less

Understanding the photoluminescence characteristics of Eu{sup 3+}-doped double-perovskite by electronic structure calculation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ghosh, Binita; Halder, Saswata; Sinha, T. P.

2016-05-23

Europium-doped luminescent barium samarium tantalum oxide Ba{sub 2}SmTaO{sub 6} (BST) has been investigated by first-principles calculation, and the crystal structure, electronic structure, and optical properties of pure BST and Eu-doped BST have been examined and compared. Based on the calculated results, the luminescence properties and mechanism of Eu-doped BST has been discussed. In the case of Eu-doped BST, there is an impurity energy band at the Fermi level, which is formed by seven spin up energy levels of Eu and act as the luminescent centre, which is evident from the band structure calculations.

In Situ Trace Element Measurements on Roda and the Origin of Diogenites

NASA Technical Reports Server (NTRS)

Mittlefehldt, David W.; Herrin, J. S.

2011-01-01

The origin of diogenites remains poorly understood. A recent model interprets many diogenites to have been formed from melts that were derived by remelting initial magma ocean cumulates, and these penultimate parent melts were then contaminated by melts derived from remelting of the basaltic (eucritic) crust to form the ultimate diogenite parent melts [1] (hereafter the remelting model). This is a very complicated petrogenesis that has profound implications for the geological evolution of 4 Vesta if correct. This model was developed based on trace element analyses of bulk rock samples that had been leached in acids to remove phosphates; the compositions of the residues were interpreted to be close to those of cumulus orthopyroxenes plagioclase, chromite and olivine [1]. In situ measurements of phases in diogenites can be used to test this model. We have begun a campaign of laser ablation ICP-MS of orthopyroxene grains in diogenites for this purpose. Here we report our first results on one diogenite, Roda. We have determined a suite of trace lithophile elements on nine, mm-sized pyroxene grains separated from Roda that have previously been studied [2, 3]. A key observation supporting the remelting model is the very low Eu/Eu* of leached residues; values too low to represent orthopyroxene that crystallized from melts with chondritic Sm/Eu and Gd/Eu [1]. (Eu* = Eu interpolated from REE diagrams.) Crustal remelts have low Sm/Eu and Gd/Eu, and orthopyroxenes that crystallized from parent melts contaminated by them would have very low Eu/Eu* [1]. Roda grains have Eu/Eu* of 0.243 to 0.026; the latter a value lower than any measured on bulk diogenite leached residues (0.041) [1]. There is a general negative correlation between Eu/Eu* and some incompatible elements (Zr, Nb, Hf), but not others (LREE). This appears inconsistent with the remelting model as it would suggest an evolving parent melt with La de-creasing as Zr increased and Eu/Eu* decreased. Grain R-15 includes trace-element-rich trapped melt phases [2, 3]. This grain has the highest Eu/Eu* and LREE contents, indicating that the trapped melt had a high Eu/Eu*. Thus, our first data on one diogenite do not provide support for the remelting model [1]. Roda is unusual in that its orthopyroxene grains show wide ranges in trace element contents [4]. Previous in situ REE analyses of grain R-15 did not reveal evidence for subsolidus equilibration with trace-element-rich trapped melt phases, and led to the suggestion that Roda may be polymict, with different grains representing different lithologies of diverse compositions [3]. Thus, based on our results on Roda, it is perhaps premature to abandon the remelting model. In situ measurements on a suite of diogenites is planned to further address this issue.

Research on high Tc superconducting compounds

NASA Technical Reports Server (NTRS)

Oliver, Frederick W. (Principal Investigator)

1996-01-01

Mossbauer research using the 21.54 kev resonance radiation of Eu-151 on the high temperature superconductors Bi(2)Ca(0.5)Eu(0.5)Sr(2)CU2O(x), and EuBa(2)CU(3)O(7-x) is performed. For the Bismuth compound the Mossbauer measurements gave a weak signal at room temperature but improved at lower temperatures. Experimental data indicated that europium is located at only one crystallographic site. Isomer shift measurements were .69 + 0.02 mm/s with respect to EuF(3). The linewidth at room temperature was found to be 2.54 mm/s. This value falls within the values observed by other researchers on Eu based 1,2,3 high-Tc compounds. Our results also show the Eu to be trivalent with no trace of divalent europium present. Superconducting europium based 1,2,3 compounds were prepared and measurements completed. Our results show the Eu to be trivalent with no trace of divalent europium present. These compounds had an average isomer shift of .73 mm/s +/- O.02 for all samples made. One of these was irradiated with 3.5 X 10(exp 16) neutrons and a comparison made of the Mossbauer parameters for the irradiated and non-irradiated samples. Experimental results showed no difference between linewidths but a measurable effect was seen for the isomer shift.

Enhanced rare earth photoluminescence in inverse opal photonic crystals and its application for pH sensing.

PubMed

Zhu, Yongsheng; Cui, Shaobo; Wang, Yinhua; Liu, Mao; Lu, Cheng; Mishra, Abhinay; Xu, Wen

2016-10-07

Concentration quenching effects of identical rare earth (RE) activator ions and energy transfer (ET) between different RE ions often compromise the photoluminescence (PL) quantum efficiency in RE based luminescence materials. Here, we demonstrate that in NaGd(WO4)2:Tb(3+), Eu(3+) inverse opal photonic crystals (IOPCs), the suppression of the emission line located in the photonic stop band (PSB) and a dramatic increase of the lifetimes of Eu(3+) and Tb(3+) ions are observed. More interestingly, the concentration quenching among Eu(3+) ions and ET from Tb(3+) to Eu(3+) is significantly relieved owing to the periodic empty cavity structure of IOPCs. As a consequence, the luminescent quantum efficiency (QE) of the NaGd(WO4)2:Tb(3+), Eu(3+) IOPCs increases ∼2 times more than that of crushed NaGd(WO4)2:Tb(3+), Eu(3+) powder. In addition, a reusable pH sensor with good linear response (pH 5-10) has been designed based on the high surface-to-volume ratio, high connectivity, and enhanced luminescence of NaGd(WO4)2:Tb(3+), Eu(3+)IOPCs, which could be applied to the dynamical detection of pH value.

Occupational exposure limits in Europe and Asia--continued divergence or global harmonization?

PubMed

Ding, Qian; Schenk, Linda; Malkiewicz, Katarzyna; Hansson, Sven Ove

2011-12-01

Occupational exposure limits (OELs) are used as a risk management tool aiming at protecting against negative health effects of occupational exposure to harmful substances. The systems of OEL development have not been standardized and divergent outcomes have been reported. However some harmonization processes have been initiated, primarily in Europe. This study investigates the state of harmonization in a global context. The OEL systems of eight Asian and seventeen European organizations are analyzed with respect to similarities and differences in: (1) the system for determining OELs, (2) the selection of substances, and (3) the levels of the OELs. The majority of the investigated organizations declare themselves to have been influenced by the American Conference of Governmental Industrial Hygienists (ACGIH), and in many cases this can be empirically confirmed. The EU harmonization process is reflected in trends towards convergence within the EU. However, comparisons of Asian and European organizations provide no obvious evidence that OELs are becoming globally harmonized. Copyright © 2011 Elsevier Inc. All rights reserved.

Building statistical associations to forecast ethylbenzene levels in European urban-traffic environments.

PubMed

Vlachokostas, Ch; Michailidou, A V; Spyridi, D; Moussiopoulos, N

2013-06-01

Emission from road traffic has become the most important source of local air pollution in numerous European cities. Epidemiological research community has established consistent associations between traffic-related substances and various health outcomes. Nevertheless, the vast majority of urban areas are characterised by infrastructure's absence to routinely monitor chemical health stressors, such as ethylbenzene. This paper aims at developing and presenting a tractable approach to reliably - and inexpensively - predict ethylbenzene trends in EU urban environments. The establishment of empirical relationships between rarely monitored pollutants such as ethylbenzene and more frequently or usually monitored, such as benzene and CO respectively, may cover the infrastructure's absence and support decision-making. Multiple regression analysis is adopted and the resulting statistical associations are applied to EU cities with available data for validation purposes. The results demonstrate that this approach is capable of capturing ethylbenzene concentration trends and should be considered as complementary to air quality monitoring. Copyright © 2013 Elsevier Ltd. All rights reserved.

Spectroelectrochemistry and Electrochemistry of Europium Ions in Alkali Chloride Melts

NASA Astrophysics Data System (ADS)

Uehara, Akihiro; Shirai, Osamu; Nagai, Takayuki; Fujii, Toshiyuki; Yamana, Hajimu

2007-04-01

In order to investigate the redox equilibrium of europium ions in molten NaCl-2CsCl, UV-Vis absorption spectrophotometry measurements were performed for Eu2+ and Eu3+ in molten NaCl- 2CsCl at 923 K under simultaneous electrolytic control of their ratio. Molar absorptivities of EuCl3 and EuCl2 in NaCl-2CsCl at 923 K were determined to be (420±21) M -1cm-1 at 31200 cm-1 and (1130±56) M-1cm-1 at 30300 cm-1, respectively. The formal redox potential of the Eu2+/Eu3+ couple in NaCl-2CsCl melt at 923 K was determined to be (-0.941 ±0.004) V vs. Cl2/Cl- by electromotive force measurements on varying concentration ratios of Eu2+ and Eu3+, which were performed using a technique based on the combination of electrolysis and spectrophotometry. Cyclic voltammetry was also carried out in order to examine the characteristics of the voltammograms for the Eu2+/Eu3+ couple in NaCl-2CsCl melt. The formal redox potential of the Eu2+/Eu3+ couple determined by a spectroelectrochemical method agreed with that determined by cyclic voltammetry [(-0.946±0.008) V vs. Cl2/Cl-]. The effects of temperature on the redox potential of the Eu2+/Eu3+ couple in NaCl-2CsCl, NaCl-KCl, LiCl-KCl, and CsCl melts were studied by cyclic voltammetry in the range from 923 to 1123 K.

Role of valence changes and nanoscale atomic displacements in BiS2-based superconductors.

PubMed

Cheng, Jie; Zhai, Huifei; Wang, Yu; Xu, Wei; Liu, Shengli; Cao, Guanghan

2016-11-22

Superconductivity within layered crystal structures has attracted sustained interest among condensed matter community, primarily due to their exotic superconducting properties. EuBiS 2 F is a newly discovered member in the BiS 2 -based superconducting family, which shows superconductivity at 0.3 K without extrinsic doping. With 50 at.% Ce substitution for Eu, superconductivity is enhanced with Tc increased up to 2.2 K. However, the mechanisms for the T c enhancement have not yet been elucidated. In this study, the Ce-doping effect on the self-electron-doped superconductor EuBiS 2 F was investigated by X-ray absorption spectroscopy (XAS). We have established a relationship between Ce-doping and the T c enhancement in terms of Eu valence changes and nanoscale atomic displacements. The new finding sheds light on the interplay among superconductivity, charge and local structure in BiS 2 -based superconductors.

The time and place of European admixture in Ashkenazi Jewish history.

PubMed

Xue, James; Lencz, Todd; Darvasi, Ariel; Pe'er, Itsik; Carmi, Shai

2017-04-01

The Ashkenazi Jewish (AJ) population is important in genetics due to its high rate of Mendelian disorders. AJ appeared in Europe in the 10th century, and their ancestry is thought to comprise European (EU) and Middle-Eastern (ME) components. However, both the time and place of admixture are subject to debate. Here, we attempt to characterize the AJ admixture history using a careful application of new and existing methods on a large AJ sample. Our main approach was based on local ancestry inference, in which we first classified each AJ genomic segment as EU or ME, and then compared allele frequencies along the EU segments to those of different EU populations. The contribution of each EU source was also estimated using GLOBETROTTER and haplotype sharing. The time of admixture was inferred based on multiple statistics, including ME segment lengths, the total EU ancestry per chromosome, and the correlation of ancestries along the chromosome. The major source of EU ancestry in AJ was found to be Southern Europe (≈60-80% of EU ancestry), with the rest being likely Eastern European. The inferred admixture time was ≈30 generations ago, but multiple lines of evidence suggest that it represents an average over two or more events, pre- and post-dating the founder event experienced by AJ in late medieval times. The time of the pre-bottleneck admixture event, which was likely Southern European, was estimated to ≈25-50 generations ago.

An integrated and sustainable EU health information system: national public health institutes' needs and possible benefits.

PubMed

Bogaert, Petronille; Van Oyen, Herman

2017-01-01

Although sound data and health information are at the basis of evidence-based policy-making and research, still no single, integrated and sustainable EU-wide public health monitoring system or health information system exists. BRIDGE Health is working towards an EU health information and data generation network covering major EU health policy areas. A stakeholder consultation with national public health institutes was organised to identify the needs to strengthen the current EU health information system and to identify its possible benefits. Five key issues for improvement were identified: (1) coherence, coordination and sustainability; (2) data harmonization, collection, processing and reporting; (3) comparison and benchmarking; (4) knowledge sharing and capacity building; and (5) transferability of health information into evidence-based policy making. The vision of an improved EU health information system was formulated and the possible benefits in relation to six target groups. Through this consultation, BRIDGE Health has identified the continuous need to strengthen the EU health information system. A better system is about sustainability, better coordination, governance and collaboration among national health information systems and stakeholders to jointly improve, harmonise, standardise and analyse health information. More and better sharing of this comparable health data allows for more and better comparative health research, international benchmarking, national and EU-wide public health monitoring. This should be developed with the view to provide the tools to fight both common and individual challenges faced by the Members States and their politicians.

The time and place of European admixture in Ashkenazi Jewish history

PubMed Central

Xue, James; Lencz, Todd; Darvasi, Ariel; Pe’er, Itsik

2017-01-01

The Ashkenazi Jewish (AJ) population is important in genetics due to its high rate of Mendelian disorders. AJ appeared in Europe in the 10th century, and their ancestry is thought to comprise European (EU) and Middle-Eastern (ME) components. However, both the time and place of admixture are subject to debate. Here, we attempt to characterize the AJ admixture history using a careful application of new and existing methods on a large AJ sample. Our main approach was based on local ancestry inference, in which we first classified each AJ genomic segment as EU or ME, and then compared allele frequencies along the EU segments to those of different EU populations. The contribution of each EU source was also estimated using GLOBETROTTER and haplotype sharing. The time of admixture was inferred based on multiple statistics, including ME segment lengths, the total EU ancestry per chromosome, and the correlation of ancestries along the chromosome. The major source of EU ancestry in AJ was found to be Southern Europe (≈60–80% of EU ancestry), with the rest being likely Eastern European. The inferred admixture time was ≈30 generations ago, but multiple lines of evidence suggest that it represents an average over two or more events, pre- and post-dating the founder event experienced by AJ in late medieval times. The time of the pre-bottleneck admixture event, which was likely Southern European, was estimated to ≈25–50 generations ago. PMID:28376121

EU FP7 project 'CAMbrella' to build European research network for complementary and alternative medicine.

PubMed

Weidenhammer, Wolfgang; Lewith, George; Falkenberg, Torkel; Fønnebø, Vinjar; Johannessen, Helle; Reiter, Bettina; Uehleke, Bernhard; von Ammon, Klaus; Baumhöfener, Franziska; Brinkhaus, Benno

2011-01-01

The status of complementary and alternative medicine (CAM) within the EU needs clarification. The definition and terminology of CAM is heterogeneous. The therapies, legal status, regulations and approaches used vary from country to country but there is widespread use by EU citizens. A coordination project funded by the EU has been launched to improve the knowledge about CAM in Europe. The project aims to evaluate the conditions surrounding CAM use and provision in Europe and to develop a roadmap for European CAM research. Specific objectives are to establish an EU network involving centres of research excellence for collaborative projects, to develop consensus-based terminology to describe CAM interventions, to create a knowledge base that facilitates the understanding of patient demand for CAM and its prevalence, to review the current legal status and policies governing CAM provision, and to explore the needs and attitudes of EU citizens with respect to CAM. Based on this information a roadmap will be created that will enable sustainable and prioritised future European research in CAM. CAMbrella encompasses 16 academic research groups from 12 European countries and will run for 36 months starting from January 2010. The project will be delivered in 9 work packages coordinated by a Management Board and directed by a Scientific Steering Committee with support of an Advisory Board. The outcomes generated will be disseminated through the project's website, peer review open access publications and a final conference, with emphasis on current and future EU policies, addressing different target audiences. Copyright © 2011 S. Karger AG, Basel.

Emergence and Outlook of Competence-Based Education in European Education Systems: An Overview

ERIC Educational Resources Information Center

Tchibozo, Guy

2011-01-01

This contribution takes stock on the emergence of competence-based education in European Union (EU) countries. The article explains how economic constraints but also educational motives led educational policies and systems in the EU to shift to competence-based education. The related instructional frame and concepts are presented, as are the major…

Synthesis and photoluminescence properties of multicolor tunable GdNbO4: Tb3+, Eu3+ phosphors based on energy transfer

NASA Astrophysics Data System (ADS)

Zhang, Lu; Yi, Shuangping; Hu, Xiaoxue; Liang, Boxin; Zhao, Weiren; Wang, Yinhai

2017-03-01

A color-tunable phosphor based on Tb3+/Eu3+ co-doped GdNbO4 were synthesized by a traditional solid-state reaction method. X-ray powder diffraction (XRD), diffuse reflectance spectra, photoluminescence spectra and decay curves were utilized to characterize the as-prepared phosphors. XRD result indicated that various concentrations Tb3+/Eu3+ single-doped and co-doped phosphors were well indexed to the pure GdNbO4 phase. The GdNbO4 host was proved to be a self-activated phosphor with broad absorption range from 200 nm to 325 nm. When Tb3+ ions were added into the host lattice, the energy transferring from host to Tb3+ was identified. And the broad absorption in the UV region was changed and enhanced. Therefore, we selected Tb3+ as the sensitizer ion, and adjusted red component from Eu3+ to control the emission color. The energy transfer from Tb3+ to Eu3+ was confirmed based on the luminescence spectra and decay curves. Furthermore, the energy transmission mechanism was deduced to be the dipole-quadrupole interaction. On the whole, the obtained GdNbO4, GdNbO4:Tb3+, and GdNbO4:Tb3+, Eu3+ phosphors may have potential application in the UV white-light-emitting diodes (w-LEDs) and display devices.

Preferential Eu Site Occupation and Its Consequences in the Ternary Luminescent Halides AB 2 I 5 : Eu 2 + ( A = Li – Cs ; B = Sr , Ba)

DOE PAGES

Fang, C.  M.; Biswas, Koushik

2015-07-22

Several rare-earth-doped, heavy-metal halides have recently been identified as potential next-generation luminescent materials with high efficiency at low cost. AB 2I 5:Eu 2+ (A=Li–Cs; B=Sr, Ba) is one such family of halides. Its members, such as CsBa 2I 5:Eu 2+ and KSr 2I 5:Eu 2+, are currently being investigated as high-performance scintillators with improved sensitivity, light yield, and energy resolution less than 3% at 662 keV. Within the AB 2I 5 family, our first-principles-based calculations reveal two remarkably different trends in Eu site occupation. The substitutional Eu ions occupy both eightfold-coordinated B1(VIII) and the sevenfold-coordinated B2(VII) sites in the Sr-containingmore » compounds. However, in the Ba-containing crystals, Eu ions strongly prefer the B2(VII)sites. This random versus preferential distribution of Eu affects their electronic properties. The calculations also suggest that in the Ba-containing compounds one can expect the formation of Eu-rich domains. These results provide atomistic insight into recent experimental observations about the concentration and temperature effects in Eu-doped CsBa 2I 5. We discuss the implications of our results with respect to luminescent properties and applications. We also hypothesize Sr, Ba-mixed quaternary iodides ABa VIIISr VIII 5:Eu as scintillators having enhanced homogeneity and electronic properties.« less

Low-temperature solvothermal synthesis of EuS hollow microspheres

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peng, Yong; Wang, Hong; Li, Peng

2014-09-15

Graphical abstract: Synthesis of EuS hollow microspheres at low-temperature via solvothermal method for the first time. - Highlights: • We adopt an improved method to synthesise the (Phen)Eu(Et{sub 2}CNS{sub 2}){sub 3} in deionized water. • We have successfully synthesised the EuS hollow microsphere at 230 °C in acetonitrile. • The price of acetonitrile is more inexpensive, so the price of preparation was reduced. - Abstract: EuS crystals are synthesized by low-temperature solvothermal decomposition of the single source precursor complex (Phen)Eu(Et{sub 2}CNS{sub 2}){sub 3} in acetonitrile. X-ray powder diffraction, scanning electron microscopy, granulocyte diameter statistical analysis, surface energy-dispersive X-ray spectroscopy analysis,more » and UV–vis absorption spectroscopy are used to characterize the structure and properties of the obtained EuS crystals. The results show that the formed EuS crystals are uniform hollow microspheres with a typical cubic phase structure of rock salt and the average particle size of 2.01 μm. The mechanisms for the thermal decomposition of the precursor complex and the formation of the EuS hollow microspheres are postulated based on the experimental observations and previous reports.« less

Origin and Luminescence of Anomalous Red-Emitting Center in Rhombohedral Ba9Lu2Si6O24:Eu(2+) Blue Phosphor.

PubMed

Liu, Yongfu; Zhang, Changhua; Cheng, Zhixuan; Zhou, Zhi; Jiang, Jun; Jiang, Haochuan

2016-09-06

We obtain a blue phosphor, Ba9Lu2Si6O24:Eu(2+) (BLS:Eu(2+)), which shows a strong emission peak at 460 nm and a weak tail from 460 to 750 nm. A 610 nm red emission is observed for the first time in this kind of rhombohedral structure material, which is much different from the same crystal structure of Ba9Sc2Si6O24:Eu(2+) and Ba9Y2Si6O24:Eu(2+). The luminescence properties and decays from 10 to 550 K are discussed. The new red emission arises from a trapped exciton state of Eu(2+) at the Ba site with a larger coordination number (12-fold). It exhibits abnormal luminescence properties with a broad bandwidth and a large Stokes shift. Under the 400 nm excitation, the external quantum efficiency of BLS:Eu(2+) is 45.4%, which is higher than the 35.7% for the commercial blue phosphor BAM:Eu(2+). If the thermal stability of BLS:Eu(2+) can be improved, it will show promising applications in efficient near-UV-based white LEDs.

Multifunctional nanocomposite based on halloysite nanotubes for efficient luminescent bioimaging and magnetic resonance imaging

PubMed Central

Zhou, Tao; Jia, Lei; Luo, Yi-Feng; Xu, Jun; Chen, Ru-Hua; Ge, Zhi-Jun; Ma, Tie-Liang; Chen, Hong; Zhu, Tao-Feng

2016-01-01

A novel multifunctional halloysite nanotube (HNT)-based Fe3O4@HNT-polyethyleneimine-Tip-Eu(dibenzoylmethane)3 nanocomposite (Fe-HNT-Eu NC) with both photoluminescent and magnetic properties was fabricated by a simple one-step hydrothermal process combined with the coupling grafting method, which exhibited high suspension stability and excellent photophysical behavior. The as-prepared multifunctional Fe-HNT-Eu NC was characterized using various techniques. The results of cell viability assay, cell morphological observation, and in vivo toxicity assay indicated that the NC exhibited excellent biocompatibility over the studied concentration range, suggesting that the obtained Fe-HNT-Eu NC was a suitable material for bioimaging and biological applications in human hepatic adenocarcinoma cells. Furthermore, the biocompatible Fe-HNT-Eu NC displayed superparamagnetic behavior with high saturation magnetization and also functioned as a magnetic resonance imaging (MRI) contrast agent in vitro and in vivo. The results of the MRI tests indicated that the Fe-HNT-Eu NC can significantly decrease the T2 signal intensity values of the normal liver tissue and thus make the boundary between the normal liver and transplanted cancer more distinct, thus effectively improving the diagnosis effect of cancers. PMID:27698562

Multifunctional nanocomposite based on halloysite nanotubes for efficient luminescent bioimaging and magnetic resonance imaging.

PubMed

Zhou, Tao; Jia, Lei; Luo, Yi-Feng; Xu, Jun; Chen, Ru-Hua; Ge, Zhi-Jun; Ma, Tie-Liang; Chen, Hong; Zhu, Tao-Feng

A novel multifunctional halloysite nanotube (HNT)-based Fe 3 O 4 @HNT-polyethyleneimine-Tip-Eu(dibenzoylmethane) 3 nanocomposite (Fe-HNT-Eu NC) with both photoluminescent and magnetic properties was fabricated by a simple one-step hydrothermal process combined with the coupling grafting method, which exhibited high suspension stability and excellent photophysical behavior. The as-prepared multifunctional Fe-HNT-Eu NC was characterized using various techniques. The results of cell viability assay, cell morphological observation, and in vivo toxicity assay indicated that the NC exhibited excellent biocompatibility over the studied concentration range, suggesting that the obtained Fe-HNT-Eu NC was a suitable material for bioimaging and biological applications in human hepatic adenocarcinoma cells. Furthermore, the biocompatible Fe-HNT-Eu NC displayed superparamagnetic behavior with high saturation magnetization and also functioned as a magnetic resonance imaging (MRI) contrast agent in vitro and in vivo. The results of the MRI tests indicated that the Fe-HNT-Eu NC can significantly decrease the T 2 signal intensity values of the normal liver tissue and thus make the boundary between the normal liver and transplanted cancer more distinct, thus effectively improving the diagnosis effect of cancers.

Recoilless fractions calculated with the nearest-neighbour interaction model by Kagan and Maslow

NASA Astrophysics Data System (ADS)

Kemerink, G. J.; Pleiter, F.

1986-08-01

The recoilless fraction is calculated for a number of Mössbauer atoms that are natural constituents of HfC, TaC, NdSb, FeO, NiO, EuO, EuS, EuSe, EuTe, SnTe, PbTe and CsF. The calculations are based on a model developed by Kagan and Maslow for binary compounds with rocksalt structure. With the exception of SnTe and, to a lesser extent, PbTe, the results are in reasonable agreement with the available experimental data and values derived from other models.

Enhanced output power from triboelectric nanogenerators based on electrospun Eu-doped polyvinylidene fluoride nanofibers

NASA Astrophysics Data System (ADS)

Kim, Hong-Seok; Park, Il-Kyu

2018-06-01

In this study, Eu-doped polyvinylidene fluoride nanofibers (PVDF NFs) were fabricated by an electrospinning method and applied as an active layer in triboelectric nanogenerators (TENGs). Structural and optical investigations showed that Eu3+ was successfully doped in the PVDF NFs and it induced discrete emissions corresponding to the electronic transitions. As the Eu content increased, the phase transformation was enhanced from the α-phase to the β-phase in the PVDF NFs, and their diameter decreased. These changes enhanced the electrical output power of the TENGs. However, the further addition of Eu resulted in precipitation of the NO3--related complex on the surface of the PVDF NFs, which was detrimental to performance of the TENGs. Due to these conflicting effects, the output power increased from 13 to 26 μW/cm2 as the Eu contents increased from 0 to 2.7 wt%, whereas it decreased drastically to 4.9 μW/cm2 when the Eu content increased further to 5.3 wt%. Therefore, the optimum amount of Eu doping has advantageous effects.

Environmental costs and renewable energy: re-visiting the Environmental Kuznets Curve.

PubMed

López-Menéndez, Ana Jesús; Pérez, Rigoberto; Moreno, Blanca

2014-12-01

The environmental costs of economic development have received increasing attention during the last years. According to the World Energy Outlook (2013) sustainable energy policies should be promoted in order to spur economic growth and environmental protection in a global context, particularly in terms of reducing greenhouse gas emissions that contribute to climate change. Within this framework, the European Union aims to achieve the "20-20-20" targets, including a 20% reduction in EU greenhouse gas emissions from 1990 levels, a raise in the share of EU energy consumption produced from renewable resources to 20% and a 20% improvement in the EU's energy efficiency. Furthermore, the EU "Energy Roadmap 2050" has been recently adopted as a basis for developing a long-term European energy framework, fighting against climate change through the implementation of energy efficiency measures and the reduction of emissions. This paper focuses on the European context and attempts to explain the impact of economic growth on CO2 emissions through the estimation of an Environmental Kuznets Curve (EKC) using panel data. Moreover, since energy seems to be at the heart of the environmental problem it should also form the core of the solution, and therefore we provide some extensions of the EKC by including renewable energy sources as explanatory variables in the proposed models. Our data sets are referred to the 27 countries of the European Union during the period 1996-2010. With this information, our empirical results provide some interesting evidence about the significant impacts of renewable energies on CO2 emissions, suggesting the existence of an extended EKC. Copyright © 2014 Elsevier Ltd. All rights reserved.

Technology and optical characterization of luminophore coordination compounds Eu(o-MBA)3Phen and NC PEPC/Eu(o-MBA)3Phen

NASA Astrophysics Data System (ADS)

Bordian, Olga; Verlan, Victor; Culeac, Ion; Iovu, Mihail; Zubareva, Vera

2016-12-01

Were obtained a new nanocomposite (NC) based on poly N-epoxy prolyl carbazol (PEPC) and the coordination compound luminophore Eu(o-MBA)3Phen, where o-MBA is o- methylbenzoic acid and Phen - phenanthroline. Nanocrystals of Eu(o-MBA)3Phen with the dimensions 50 nm were uniformly incorporated into the PEPC polymer matrix with various concentrations. The absorption spectra of coordination compounds and thin layers of NC PEPC/Eu(o-MBA)3Phen revealed 1 intensive absorption bands at 2.02 eV. Photoluminescence (PL) spectra showed an intense red luminescence at 578 - 699 nm, which is assigned to the transitions 4D0->7Fi (i= 0,1,2 3 4) in the 4f-shell of the Eu3+ ion.

Travelling home for treatment and EU patients' rights to care abroad: results of a survey among German students at Maastricht University.

PubMed

Glinos, Irene A; Doering, Nora; Maarse, Hans

2012-04-01

Empirical evidence on patient mobility in Europe is lacking despite widespread legal, policy and media attention which the phenomenon attracts. This paper presents quantitative data on the health care seeking behaviour of German students at Maastricht University in the Netherlands. A cross-sectional survey design was applied with a mixed-methods approach including open and closed questions. Questionnaire items were based on a theoretical model of patient mobility and input from focus group discussions with German students living in Maastricht. 235 valid surveys were completed, representing ca. 8% of the target population. Data collection took place in Oct-Dec 2010. Of respondents who received medical care over the last two years, 97% returned to Germany; of these, 76% travelled to their home city for medical treatment. 72% received care only in Germany, i.e. not even once in Maastricht. Distance partly influenced whether students travelled to Germany, returned home or stayed in Maastricht, and the type of care accessed. Key motivations were familiarity with home providers/system, and reimbursement issues. In the context of the new EU Directive on patients' rights, the findings call into question whether Europeans use entitlements to cross-border care and what the real potential of patient mobility is. The results demonstrate the existence and magnitude of return movements as a sub-group of patient mobility. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Economic losses to buildings due to tsunami impact: the case of Rhodes city, Greece

NASA Astrophysics Data System (ADS)

Triantafyllou, Ioanna; Novikova, Tatyana; Papadopoulos, Gerassimos

2017-04-01

The expected economic losses to buildings due to the tsunami impact is of particular importance for the tsunami risk management. However, only few efforts can be found in this direction. In this study we approached this issue selecting the city of Rhodes Isl., Greece, as a test-site. The methodological steps followed include (a) selection of worst case scenario in the study area based on the tsunami history of the area which includes several powerful events, e.g. 142 AD, 1303, 1481, 1609, 1741, (b) numerical simulation of the tsunami and determination of the inundation zone, (c) application of the DAMASCHE empirical tool, produced by the SCHEMA EU-FP6 project, for the calculation of the damage level expected at each one of the buildings as a function of the water depth in the inundation area, (d) calculation of the buildings that would need reparation after partial damage and of those that would need reconstruction after total destruction, (e) calculation of the cost implied for both reparation and reconstruction. The several data sets which are needed for the execution of these steps, are susceptible to uncertainties and, therefore, the final results are quite sensitive to changes of the data sets. Alternative costs were calculated by taking into account the several uncertainties involved. This research is a contribution to the EU-FP7 tsunami research project ASTARTE (Assessment, Strategy And Risk Reduction for Tsunamis in Europe), grant agreement no: 603839, 2013-10-30.

Photophysical studies of europium coordination polymers based on a tetracarboxylate ligand.

PubMed

Gai, Yan-Li; Jiang, Fei-Long; Chen, Lian; Bu, Yang; Su, Kong-Zhao; Al-Thabaiti, Shaeel A; Hong, Mao-Chun

2013-07-01

Reaction of europium sulfate octahydrate with p-terphenyl-3,3″,5,5″-tetracarboxylic acid (H4ptptc) in a mixed solvent system has afforded three new coordination polymers formulated as {[Eu(ptptc)0.75(H2O)2]·0.5DMF·1.5H2O}n (1), {[Me2H2N]2 [Eu2(ptptc)2(H2O)(DMF)]·1.5DMF·7H2O}n (2), and {[Eu(Hptptc)(H2O)4]·0.5DMF·H2O}n (3). Complex 1 exhibits a three-dimensional (3D) metal-organic framework based on {Eu2(μ2-COO)2(COO)4}n chains, complex 2 shows a 3D metal-organic framework constructed by [Eu2(μ2-COO)2(COO)6](2-) dimetallic subunits, and complex 3 features a 2D layer architecture assembling to 3D framework through π···π interactions. All complexes exhibit the characteristic red luminescence of Eu(III) ion. The triplet state of ligand H4ptptc matches well with the emission level of Eu(III) ion, which allows the preparation of new optical materials with enhanced luminescence properties. The luminescence properties of these complexes are further studied in terms of their emission quantum yields, emission lifetimes, and the radiative/nonradiative rates.

Urban Earthquake Shaking and Loss Assessment

NASA Astrophysics Data System (ADS)

Hancilar, U.; Tuzun, C.; Yenidogan, C.; Zulfikar, C.; Durukal, E.; Erdik, M.

2009-04-01

This study, conducted under the JRA-3 component of the EU NERIES Project, develops a methodology and software (ELER) for the rapid estimation of earthquake shaking and losses the Euro-Mediterranean region. This multi-level methodology developed together with researchers from Imperial College, NORSAR and ETH-Zurich is capable of incorporating regional variability and sources of uncertainty stemming from ground motion predictions, fault finiteness, site modifications, inventory of physical and social elements subjected to earthquake hazard and the associated vulnerability relationships. GRM Risk Management, Inc. of Istanbul serves as sub-contractor tor the coding of the ELER software. The methodology encompasses the following general steps: 1. Finding of the most likely location of the source of the earthquake using regional seismotectonic data base and basic source parameters, and if and when possible, by the estimation of fault rupture parameters from rapid inversion of data from on-line stations. 2. Estimation of the spatial distribution of selected ground motion parameters through region specific ground motion attenuation relationships and using shear wave velocity distributions.(Shake Mapping) 4. Incorporation of strong ground motion and other empirical macroseismic data for the improvement of Shake Map 5. Estimation of the losses (damage, casualty and economic) at different levels of sophistication (0, 1 and 2) that commensurate with the availability of inventory of human built environment (Loss Mapping) Level 2 analysis of the ELER Software (similar to HAZUS and SELENA) is essentially intended for earthquake risk assessment (building damage, consequential human casualties and macro economic loss quantifiers) in urban areas. The basic Shake Mapping is similar to the Level 0 and Level 1 analysis however, options are available for more sophisticated treatment of site response through externally entered data and improvement of the shake map through incorporation of accelerometric and other macroseismic data (similar to the USGS ShakeMap System). The building inventory data for the Level 2 analysis will consist of grid (geo-cell) based urban building and demographic inventories. For building grouping the European building typology developed within the EU-FP5 RISK-EU project is used. The building vulnerability/fragility relationships to be used can be user selected from a list of applicable relationships developed on the basis of a comprehensive study, Both empirical and analytical relationships (based on the Coefficient Method, Equivalent Linearization Method and the Reduction Factor Method of analysis) can be employed. Casualties in Level 2 analysis are estimated based on the number of buildings in different damaged states and the casualty rates for each building type and damage level. Modifications to the casualty rates can be used if necessary. ELER Level 2 analysis will include calculation of direct monetary losses as a result building damage that will allow for repair-cost estimations and specific investigations associated with earthquake insurance applications (PML and AAL estimations). ELER Level 2 analysis loss results obtained for Istanbul for a scenario earthquake using different techniques will be presented with comparisons using different earthquake damage assessment software. The urban earthquake shaking and loss information is intented for dissemination in a timely manner to related agencies for the planning and coordination of the post-earthquake emergency response. However the same software can also be used for scenario earthquake loss estimation, related Monte-Carlo type simulations and eathquake insurance applications.

Trace Elements and Oxygen Isotope Zoning of the Sidewinder Skarn

NASA Astrophysics Data System (ADS)

Draper, C.; Gevedon, M. L.; Barnes, J.; Lackey, J. S.; Jiang, H.; Lee, C. T.

2016-12-01

Skarns of the Verde Antique Quarry and White Horse Mountain areas of the Sidewinder Range give insight into the paleohydrothermal systems operating in the California's Jurassic arc in the Southwestern Mojave Desert. Garnet from these skarns is iron rich: Xand= 55-100. Laser fluorination measurements show oxygen isotope (δ18O) compositions of garnet crystals and crystals domains have large ranges: -3.1‰ to +4.4‰ and -8.9‰ to +3.4‰, respectively. In general, the garnet cores have more negative δ18O values than rims, although oscillations are present. Negative values have been interpreted as influx of meteoric fluid and positive values as increased magmatic input. Here we report major and trace element concentrations for 17 core to rim Sidewinder garnet transects. REEs concentrations are low in all crystals, with total REE concentrations ranging from 0.710 ppm to 33.7 ppm, values that are lower than Cretaceous skarn garnets in the Sierra Nevada in the White Chief and Empire Mt skarns. Such low concentrations are likely due to the higher fraction of meteoric fluids during formation of the Sidewinder skarns. REE concentrations decrease from core to rim (REE core average=12.2ppm, REE rim average=7.21ppm). This is slightly more pronounced in the LREEs than in the HREEs (LaN/YbN core average= 10.9; rim average= 9.73, normalized to Chondrite). X­and tends to decrease core to rim in the Verde Antique skarn, whereas, Xand of the White Horse skarn does not correlate with distance from core. A large positive Eu anomaly (Eu/Eu* = 3­-30) in garnet from both skarns suggests oxidizing fluid conditions. Oxygen isotope data from garnet in these same skarns show periods of time with increased proportion of magmatic derived fluids in the total fluid budget. However, there is no corresponding widespread increase in total REE concentrations. Other studies of skarns from the western Sierra Nevadan arc (White Chief and Empire Mountain) observe complete decoupling of d18O values and trace element compositions. Future modeling should consider modal abundance of fluid soluble minerals in cooling and altering plutons to probe the REE budget.

Europium anomalies in plagioclase-free deep arc cumulates constrain the redox evolution of arc magmas

NASA Astrophysics Data System (ADS)

Tang, M.; Erdman, M.; Eldridge, G.; Lee, C. T.

2017-12-01

Arc lavas are generally more oxidized than mid-ocean-ridge basalts, but how arc lavas acquire their oxidized signatures remains poorly understood. Iron oxidation state in melts have been used to suggest that fluids released from subducted slab may oxidize the sub-arc mantle and produce oxidized arc magmas from the source (e.g., Carmichael, 1991; Kelley and Cottrell), but redox-sensitive trace element and Fe isotope signatures of basalts also suggest that oxidation may happen during magma differentiation (e.g., Dauphas et al., 2009; Lee et al., 2005, 2010). One potential problem, however, is that all of these studies, represent indirect constraints on the primary, pre-erupted magma oxidation state. Here, we examine the Eu systematics of primitive, deep-seated (>45-80 km) arc cumulates, which provide the most direct constraint on arc magmas before they rise into the crust. The ratio of Eu2+/Eu3+ is a function of fo2, temperature and composition. Eu2+ is more incompatible than Eu3+ except in plagioclase. Combining Eu partitioning in minerals and experimentally calibrated Eu oxybarometer (Burnham et al., 2015) allows the application of mineral Eu anomalies in constraining magma redox conditions. The cumulates are represented by garnet-bearing pyroxenites from Arizona, USA and are arc cumulates. Because they derive from depths > 60 km, plagioclase was never present during their petrogenesis, hence any Eu anomalies reflect the effects of oxygen fugacity. We find that the most primitive cumulates have negative Eu anomalies in garnet and clinopyroxene (Eu/Eu*<1), despite the fact that depths of differentiation were too high to stabilize plagioclase. We further show that garnet and clinopyroxene Eu/Eu* increases with differentiation (decreasing Mg#), consistent with Eu2+ being more incompatible than Eu3+. Based on the Eu oxybarometer calibrated by Burnham et al. (2015), the Eu deficits in the most primitive cumulate (Mg# = 77) suggest crystallization at Dlogfo2 of FMQ-1, similar to that of mid-ocean-ridge basalts. Crystal fractionation modelling shows that the increasing Eu/Eu* in the evolved cumulates require fo2 to increase by at least 2 log units as the fractionated cumulate Mg# decreases from 77 to 53. These observations suggest that the oxidized nature of arc magmas occurs during intracrustal differentiation.

Low-lying electronic structure of EuH, EuOH, and EuO neutrals and anions determined by anion photoelectron spectroscopy and DFT calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kafader, Jared O.; Ray, Manisha; Jarrold, Caroline Chick, E-mail: cjarrold@indiana.edu

2015-07-21

The anion photoelectron (PE) spectra of EuH{sup −} and the PE spectrum of overlapping EuOH{sup −} and EuO{sup −} anions are presented and analyzed with supporting results from density functional theory calculations on the various anions and neutrals. Results point to ionically bound, high-spin species. EuH and EuOH anions and neutrals exhibit analogous electronic structures: Transitions from {sup 8}Σ{sup −} anion ground states arising from the 4f{sup 7}σ{sub 6s}{sup 2} superconfiguration to the close-lying neutral {sup 9}Σ{sup −} and {sup 7}Σ{sup −} states arising from the 4f{sup 7}σ{sub 6s} superconfiguration are observed spaced by an energy interval similar to themore » free Eu{sup +} [4f{sup 7}6s] {sup 9}S - {sup 7}S splitting. The electron affinities (EAs) of EuH and EuOH are determined to be 0.771 ± 0.009 eV and 0.700 ± 0.011 eV, respectively. Analysis of spectroscopic features attributed to EuO{sup −} photodetachment is complicated by the likely presence of two energetically competitive electronic states of EuO{sup −} populating the ion beam. However, based on the calculated relative energies of the close-lying anion states arising from the 4f{sup 7}σ{sub 6s} and 4f{sup 6}σ{sub 6s}{sup 2} configurations and the relative energies of the one-electron accessible 4f{sup 7} and 4f{sup 6}σ{sub 6s} neutral states based on ligand-field theory [M. Dulick, E. Murad, and R. F. Barrow, J. Chem. Phys. 85, 385 (1986)], the remaining features are consistent with the 4f{sup 6}σ{sub 6s}{sup 2}  {sup 7}Σ{sup −} and 4f{sup 7}σ{sub 6s}{sup 7}Σ{sup −} anion states lying very close in energy (the former was calculated to be 0.15 eV lower in energy than the latter), though the true anion ground state and neutral EA could not be established unambiguously. Calculations on the various EuO anion and neutral states suggest 4f-orbital overlap with 2p orbitals in species with 4f{sup 6} occupancy.« less

Comparing motor-vehicle crash risk of EU and US vehicles.

PubMed

Flannagan, Carol A C; Bálint, András; Klinich, Kathleen D; Sander, Ulrich; Manary, Miriam A; Cuny, Sophie; McCarthy, Michael; Phan, Vuthy; Wallbank, Caroline; Green, Paul E; Sui, Bo; Forsman, Åsa; Fagerlind, Helen

2018-08-01

This study examined the hypotheses that passenger vehicles meeting European Union (EU) safety standards have similar crashworthiness to United States (US) -regulated vehicles in the US driving environment, and vice versa. The first step involved identifying appropriate databases of US and EU crashes that include in-depth crash information, such as estimation of crash severity using Delta-V and injury outcome based on medical records. The next step was to harmonize variable definitions and sampling criteria so that the EU data could be combined and compared to the US data using the same or equivalent parameters. Logistic regression models of the risk of a Maximum injury according to the Abbreviated Injury Scale of 3 or greater, or fatality (MAIS3+F) in EU-regulated and US-regulated vehicles were constructed. The injury risk predictions of the EU model and the US model were each applied to both the US and EU standard crash populations. Frontal, near-side, and far-side crashes were analyzed together (termed "front/side crashes") and a separate model was developed for rollover crashes. For the front/side model applied to the US standard population, the mean estimated risk for the US-vehicle model is 0.035 (sd = 0.012), and the mean estimated risk for the EU-vehicle model is 0.023 (sd = 0.016). When applied to the EU front/side population, the US model predicted a 0.065 risk (sd = 0.027), and the EU model predicted a 0.052 risk (sd = 0.025). For the rollover model applied to the US standard population, the US model predicted a risk of 0.071 (sd = 0.024), and the EU model predicted 0.128 risk (sd = 0.057). When applied to the EU rollover standard population, the US model predicted a 0.067 risk (sd = 0.024), and the EU model predicted 0.103 risk (sd = 0.040). The results based on these methods indicate that EU vehicles most likely have a lower risk of MAIS3+F injury in front/side impacts, while US vehicles most likely have a lower risk of MAIS3+F injury in llroovers. These results should be interpreted with an understanding of the uncertainty of the estimates, the study limitations, and our recommendations for further study detailed in the report. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Health impact assessment and monetary valuation of IQ loss in pre-school children due to lead exposure through locally produced food.

PubMed

Bierkens, J; Buekers, J; Van Holderbeke, M; Torfs, R

2012-01-01

A case study has been performed which involved the full chain assessment from policy drivers to health effect quantification of lead exposure through locally produced food on loss of IQ in pre-school children at the population level across the EU-27, including monetary valuation of the estimated health impact. Main policy scenarios cover the period from 2000 to 2020 and include the most important Community policy developments expected to affect the environmental release of lead (Pb) and corresponding human exposure patterns. Three distinct scenarios were explored: the emission situation based on 2000 data, a business-as-usual scenario (BAU) up to 2010 and 2020 and a scenario incorporating the most likely technological change expected (Most Feasible Technical Reductions, MFTR) in response to current and future legislation. Consecutive model calculations (MSCE-HM, WATSON, XtraFOOD, IEUBK) were performed by different partners on the project as part of the full chain approach to derive estimates of blood lead (B-Pb) levels in children as a consequence of the consumption of local produce. The estimated B-Pb levels were translated into an average loss of IQ points/child using an empirical relationship based on a meta-analysis performed by Schwartz (1994). The calculated losses in IQ points were subsequently further translated into the average cost/child using a cost estimate of €10.000 per loss of IQ point based on data from a literature review. The estimated average reduction of cost/child (%) for all countries considered in 2010 under BAU and MFTR are 12.16 and 18.08% as compared to base line conditions, respectively. In 2020 the percentages amount to 20.19 and 23.39%. The case study provides an example of the full-chain impact pathway approach taking into account all foreseeable pathways both for assessing the environmental fate and the associated human exposure and the mode of toxic action to arrive at quantitative estimates of health impacts at the individual and the population risk levels alike at EU scale. As the estimated B-Pb levels fall below the range of observed biomonitoring data collected for pre-school children in 6 different EU countries, results presented in this paper are only a first approximation of the costs entailed in the health effects of exposure to lead and the potential benefits that may arise from MFTR measures inscribed in Commission policies. Copyright © 2011 Elsevier B.V. All rights reserved.

Derivation of effective fission gas diffusivities in UO2 from lower length scale simulations and implementation of fission gas diffusion models in BISON

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andersson, Anders David Ragnar; Pastore, Giovanni; Liu, Xiang-Yang

2014-11-07

This report summarizes the development of new fission gas diffusion models from lower length scale simulations and assessment of these models in terms of annealing experiments and fission gas release simulations using the BISON fuel performance code. Based on the mechanisms established from density functional theory (DFT) and empirical potential calculations, continuum models for diffusion of xenon (Xe) in UO 2 were derived for both intrinsic conditions and under irradiation. The importance of the large X eU3O cluster (a Xe atom in a uranium + oxygen vacancy trap site with two bound uranium vacancies) is emphasized, which is a consequencemore » of its high mobility and stability. These models were implemented in the MARMOT phase field code, which is used to calculate effective Xe diffusivities for various irradiation conditions. The effective diffusivities were used in BISON to calculate fission gas release for a number of test cases. The results are assessed against experimental data and future directions for research are outlined based on the conclusions.« less

Near-infrared luminescence from Y2O3:Eu3+, Yb3+ prepared by sol-gel method.

PubMed

Xie, Ying; Xiao, Lin J; Yan, Feng Q; Chen, Yong J; Li, Wen Z; Geng, Xiu J

2014-06-01

Eu3+ and Yb3+ codoped Y2O3 phosphors were synthesized by the sol-gel method. The phosphors possess absorption in the region of 300-550 nm, exhibiting an intense NIR emission of Yb3+ around 1000 nm, which is suitable for matching the maximum spectral response of c-Si solar cells. The optimum composition of Eu3+ and Yb3+ codoped Y2O3 was (Y1.94Yb0.04Eu0.02)2O3. It is observed that two-step energy transfer occurs from the 5D2 level of Eu3+ situated around (466 nm) exciting two neighboring Yb3+ ions to the 2F5/2 level (1000 nm). The down-conversion material based on Eu(3+)- Yb3+ couple may have great potential applications in c-Si solar cells to enhance their photovoltaic conversion efficiency via spectral modification.

A neutron scintillator based on transparent nanocrystalline CaF{sub 2}:Eu glass ceramic

DOE Office of Scientific and Technical Information (OSTI.GOV)

Struebing, Christian; Kang, Zhitao, E-mail: zhitao.kang@gtri.gatech.edu; School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332

2016-04-11

There are no efficient Eu{sup 2+} doped glass neutron scintillators reported due to low doping concentrations of Eu{sup 2+} and the amorphous nature of the glass matrix. In this work, an efficient CaF{sub 2}:Eu glass ceramic neutron scintillator was prepared by forming CaF{sub 2}:Eu nanocrystals in a {sup 6}Li-containing glass matrix. Through appropriate thermal treatments, the scintillation light yield of the transparent glass ceramic was increased by a factor of at least 46 compared to the as-cast amorphous glass. This improvement was attributed to more efficient energy transfer from the CaF{sub 2} crystals to the Eu{sup 2+} emitting centers. Furthermore » light yield improvement is expected if the refractive index of the glass matrix can be matched to the CaF{sub 2} crystal.« less

Implementation of Inquiry-Based Science Education in Different Countries: Some Reflections

ERIC Educational Resources Information Center

Rundgren, Carl-Johan

2018-01-01

In this forum article, I reflect on issues related to the implementation of inquiry-based science education (IBSE) in different countries. Regarding education within the European Union (EU), the Bologna system has in later years provided extended coordination and comparability at an organizational level. However, the possibility of the EU to…

Evidence based policy making in the European Union: the role of the scientific community.

PubMed

Majcen, Špela

2017-03-01

In the times when the acquis of the European Union (EU) has developed so far as to reach a high level of technical complexity, in particular in certain policy fields such as environmental legislation, it is important to look at what kind of information and data policy decisions are based on. This position paper looks at the extent to which evidence-based decision-making process is being considered in the EU institutions when it comes to adopting legislation in the field of environment at the EU level. The paper calls for closer collaboration between scientists and decision-makers in view of ensuring that correct data is understood and taken into consideration when drafting, amending, negotiating and adopting new legal texts at all levels of the EU decision-making process. It concludes that better awareness of the need for such collaboration among the decision-makers as well as the scientific community would benefit the process and quality of the final outcomes (legislation).

Tunable Luminescence in Sr2MgSi2O7:Tb3+, Eu3+Phosphors Based on Energy Transfer

PubMed Central

Li, Minhong; Wang, Lili; Ran, Weiguang; Deng, Zhihan; Shi, Jinsheng; Ren, Chunyan

2017-01-01

A series of Tb3+, Eu3+-doped Sr2MgSi2O7 (SMSO) phosphors were synthesized by high temperature solid-state reaction. X-ray diffraction (XRD) patterns, Rietveld refinement, photoluminescence spectra (PL), and luminescence decay curves were utilized to characterize each sample’s properties. Intense green emission due to Tb3+ 5D4→7F5 transition was observed in the Tb3+ single-doped SMSO sample, and the corresponding concentration quenching mechanism was demonstrated to be a diople-diople interaction. A wide overlap between Tb3+ emission and Eu3+ excitationspectraresults in energy transfer from Tb3+ to Eu3+. This has been demonstrated by the emission spectra and decay curves of Tb3+ in SMSO:Tb3+, Eu3+ phosphors. Energy transfer mechanism was determined to be a quadrupole-quadrupole interaction. And critical distance of energy transfer from Tb3+ to Eu3+ ions is calculated to be 6.7 Å on the basis of concentration quenching method. Moreover, white light emission was generated via adjusting concentration ratio of Tb3+ and Eu3+ in SMSO:Tb3+, Eu3+ phosphors. All the results indicate that SMSO:Tb3+, Eu3+ is a promising single-component white light emitting phosphor. PMID:28772587

Luminescence study on Eu3+ doped Y2O3 nanoparticles: particle size, concentration and core-shell formation effects

NASA Astrophysics Data System (ADS)

Robindro Singh, L.; Ningthoujam, R. S.; Sudarsan, V.; Srivastava, Iti; Dorendrajit Singh, S.; Dey, G. K.; Kulshreshtha, S. K.

2008-02-01

Nanoparticles of Eu3+ doped Y2O3 (core) and Eu3+ doped Y2O3 covered with Y2O3 shell (core-shell) are prepared by urea hydrolysis for 3 h in ethylene glycol medium at a relatively low temperature of 140 °C, followed by heating at 500 and 900 °C. Particle sizes determined from x-ray diffraction and transmission electron microscopic studies are 11 and 18 nm for 500 and 900 °C heated samples respectively. Based on the luminescence studies of 500 and 900 °C heated samples, it is confirmed that there is no particle size effect on the peak positions of Eu3+ emission, and optimum luminescence intensity is observed from the nanoparticles with a Eu3+ concentration of 4-5 at.%. A luminescence study establishes that the Eu3+ environment in amorphous Y (OH)3 is different from that in crystalline Y2O3. For a fixed concentration of Eu3+ doping, there is a reduction in Eu3+ emission intensity for core-shell nanoparticles compared to that of core nanoparticles, and this has been attributed to the concentration dilution effect. Energy transfer from the host to Eu3+ increases with increase of crystallinity.

Eucommia ulmoides Ameliorates Glucotoxicity by Suppressing Advanced Glycation End-Products in Diabetic Mice Kidney

PubMed Central

Do, Moon Ho; Hur, Jinyoung; Choi, Jiwon; Kim, Mina; Kim, Min Jung; Kim, Yoonsook; Ha, Sang Keun

2018-01-01

Eucommia ulmoides Oliv. (EU), also known as Du-Zhong, is a medicinal herb commonly used in Asia to treat hypertension and diabetes. Despite evidence of the protective effects of EU against diabetes, its precise effects and mechanisms of action against advanced glycation end-products (AGEs) are unclear. In this study, we evaluated the effects of EU on AGEs-induced renal disease and explored the possible underlying mechanisms using streptozotocin (STZ)-induced diabetic mice. STZ-induced diabetic mice received EU extract (200 mg/kg) orally for 6 weeks. EU treatment did not change blood glucose and glycated hemoglobin (HbA1c) levels in diabetic mice. However, the EU-treated group showed a significant increase in the protein expression and activity of glyoxalase 1 (Glo1), which detoxifies the AGE precursor, methylglyoxal (MGO). EU significantly upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression but downregulated that of receptor for AGE (RAGE). Furthermore, histological and immunohistochemical analyses of kidney tissue showed that EU reduced periodic acid–Schiff (PAS)-positive staining, AGEs, and MGO accumulation in diabetic mice. Based on these findings, we concluded that EU ameliorated the renal damage in diabetic mice by inhibiting AGEs formation and RAGE expression and reducing oxidative stress, through the Glo1 and Nrf2 pathways. PMID:29495397

Eucommia ulmoides Ameliorates Glucotoxicity by Suppressing Advanced Glycation End-Products in Diabetic Mice Kidney.

PubMed

Do, Moon Ho; Hur, Jinyoung; Choi, Jiwon; Kim, Mina; Kim, Min Jung; Kim, Yoonsook; Ha, Sang Keun

2018-02-26

Eucommia ulmoides Oliv. (EU), also known as Du-Zhong, is a medicinal herb commonly used in Asia to treat hypertension and diabetes. Despite evidence of the protective effects of EU against diabetes, its precise effects and mechanisms of action against advanced glycation end-products (AGEs) are unclear. In this study, we evaluated the effects of EU on AGEs-induced renal disease and explored the possible underlying mechanisms using streptozotocin (STZ)-induced diabetic mice. STZ-induced diabetic mice received EU extract (200 mg/kg) orally for 6 weeks. EU treatment did not change blood glucose and glycated hemoglobin (HbA1c) levels in diabetic mice. However, the EU-treated group showed a significant increase in the protein expression and activity of glyoxalase 1 (Glo1), which detoxifies the AGE precursor, methylglyoxal (MGO). EU significantly upregulated nuclear factor erythroid 2-related factor 2 (Nrf2) expression but downregulated that of receptor for AGE (RAGE). Furthermore, histological and immunohistochemical analyses of kidney tissue showed that EU reduced periodic acid-Schiff (PAS)-positive staining, AGEs, and MGO accumulation in diabetic mice. Based on these findings, we concluded that EU ameliorated the renal damage in diabetic mice by inhibiting AGEs formation and RAGE expression and reducing oxidative stress, through the Glo1 and Nrf2 pathways.

Soil radium, soil gas radon and indoor radon empirical relationships to assist in post-closure impact assessment related to near-surface radioactive waste disposal.

PubMed

Appleton, J D; Cave, M R; Miles, J C H; Sumerling, T J

2011-03-01

Least squares (LS), Theil's (TS) and weighted total least squares (WTLS) regression analysis methods are used to develop empirical relationships between radium in the ground, radon in soil and radon in dwellings to assist in the post-closure assessment of indoor radon related to near-surface radioactive waste disposal at the Low Level Waste Repository in England. The data sets used are (i) estimated ²²⁶Ra in the < 2 mm fraction of topsoils (eRa226) derived from equivalent uranium (eU) from airborne gamma spectrometry data, (ii) eRa226 derived from measurements of uranium in soil geochemical samples, (iii) soil gas radon and (iv) indoor radon data. For models comparing indoor radon and (i) eRa226 derived from airborne eU data and (ii) soil gas radon data, some of the geological groupings have significant slopes. For these groupings there is reasonable agreement in slope and intercept between the three regression analysis methods (LS, TS and WTLS). Relationships between radon in dwellings and radium in the ground or radon in soil differ depending on the characteristics of the underlying geological units, with more permeable units having steeper slopes and higher indoor radon concentrations for a given radium or soil gas radon concentration in the ground. The regression models comparing indoor radon with soil gas radon have intercepts close to 5 Bq m⁻³ whilst the intercepts for those comparing indoor radon with eRa226 from airborne eU vary from about 20 Bq m⁻³ for a moderately permeable geological unit to about 40 Bq m⁻³ for highly permeable limestone, implying unrealistically high contributions to indoor radon from sources other than the ground. An intercept value of 5 Bq m⁻³ is assumed as an appropriate mean value for the UK for sources of indoor radon other than radon from the ground, based on examination of UK data. Comparison with published data used to derive an average indoor radon: soil ²²⁶Ra ratio shows that whereas the published data are generally clustered with no obvious correlation, the data from this study have substantially different relationships depending largely on the permeability of the underlying geology. Models for the relatively impermeable geological units plot parallel to the average indoor radon: soil ²²⁶Ra model but with lower indoor radon: soil ²²⁶Ra ratios, whilst the models for the permeable geological units plot parallel to the average indoor radon: soil ²²⁶Ra model but with higher than average indoor radon: soil ²²⁶Ra ratios. Copyright © 2010 Natural Environment Research Council. Published by Elsevier Ltd.. All rights reserved.

Regulation of non-relevant metabolites of plant protection products in drinking and groundwater in the EU: Current status and way forward.

PubMed

Laabs, V; Leake, C; Botham, P; Melching-Kollmuß, S

2015-10-01

Non-relevant metabolites are defined in the EU regulation for plant protection product authorization and a detailed definition of non-relevant metabolites is given in an EU Commission DG Sanco (now DG SANTE - Health and Food Safety) guidance document. However, in water legislation at EU and member state level non-relevant metabolites of pesticides are either not specifically regulated or diverse threshold values are applied. Based on their inherent properties, non-relevant metabolites should be regulated based on substance-specific and toxicity-based limit values in drinking and groundwater like other anthropogenic chemicals. Yet, if a general limit value for non-relevant metabolites in drinking and groundwater is favored, an application of a Threshold of Toxicological Concern (TTC) concept for Cramer class III compounds leads to a threshold value of 4.5 μg L(-1). This general value is exemplarily shown to be protective for non-relevant metabolites, based on individual drinking water limit values derived for a set of 56 non-relevant metabolites. A consistent definition of non-relevant metabolites of plant protection products, as well as their uniform regulation in drinking and groundwater in the EU, is important to achieve legal clarity for all stakeholders and to establish planning security for development of plant protection products for the European market. Copyright © 2015 Elsevier Inc. All rights reserved.

"Unplugged," a European School-Based Program for Substance Use Prevention among Adolescents: Overview of Results from the EU-Dap Trial

ERIC Educational Resources Information Center

Vigna-Taglianti, Federica D.; Galanti, Maria Rosaria; Burkhart, Gregor; Caria, Maria Paola; Vadrucci, Serena; Faggiano, Fabrizio

2014-01-01

The EU-Dap study aimed to develop and evaluate a school-based curriculum for the prevention of substance use among young people. The school curriculum, "Unplugged," is based on social influence approach and addresses social and personal skills, knowledge, and normative beliefs. It consists of 12 one-hour interactive sessions delivered by…

Photoluminescence Properties of Red-Emitting Ca3Sr3-x(PO4)4:xEu3+ Phosphors for White Light-Emitting Diodes.

PubMed

Hakeem, D A; Park, K

2015-07-01

The photoluminescent properties of the Eu(3+)-activated Ca3Sr3(PO4)4 phosphors prepared by a solution combustion method were investigated. The excitation spectra of Ca3Sr3-x(PO4)4:xEu3+ (0.05 ≤ x ≤ 0.6) phosphors under 614 nm wavelength showed a broad band centered at 266 nm along with other peaks at 320, 362, 381, 394, 414, 464, and 534 nm. The emission spectra observed in the range of 450 to 750 nm under excitation at 394 nm were ascribed to the 5D0-7F1-4 transitions of Eu3+ ions. The Ca3Sr3-x(PO4)4:xEu3+ phosphors showed the strongest red emission at 614 nm due to the electric dipole 5DO -->7F2 transition of Eu3+. The strongest emission intensity was obtained for the Eu3+ ions of x = 0.5. The prepared Ca3Sr3-x(PO4)4:xEu3+ can be used as an efficient red phosphor for UV-based white LEDs.

Antenna Effect on the Organic Spacer-Modified Eu-Doped Layered Gadolinium Hydroxide for the Detection of Vanadate Ions over a Wide pH Range.

PubMed

Jeong, Heejin; Lee, Byung-Il; Byeon, Song-Ho

2016-05-04

The excitation of the adsorbed vanadate group led to the red emission arising from the efficient energy transfer to Eu-doped layered gadolinium hydroxide (LGdH:Eu). This light-harvesting antenna effect allowed LGdH:Eu to detect selectively a vanadate in aqueous solution at different pHs. Because vanadate exists in various forms by extensive oligomerization and protonation reactions in aqueous solution depending on pH, it is important to detect a vanadate regardless of its form over a wide pH range. In particular, spacer molecules with long alkyl chains greatly facilitated access of a vanadate antenna into the interlayer surface of LGdH:Eu. The concomitant increase in adsorption capacity of LGdH:Eu achieved a strong antenna effect of vanadate on the red emission from Eu(3+). When a suspension containing LGdH:Eu nanosheets (1.0 g/L) was used, the vanadate concentration down to 1 × 10(-5) M could even be visually monitored, and the detection limit based on the (5)D0 → (7)F2 emission intensity could reach 4.5 × 10(-8) M.

Differences in the progress of the biopesticide revolution between the EU and other major crop-growing regions.

PubMed

Balog, Adalbert; Hartel, Tibor; Loxdale, Hugh D; Wilson, Kenneth

2017-11-01

The five-year value in the compound annual growth rate of the biopesticides sector is predicted to be 16% by 2017 and to produce a global market worth $US 10 billion. Despite this, several impediments occur within the EU that negatively affect biopesticide research and innovation. At present, there are fewer biopesticide-active substances registered in the EU compared with the United States, India, Brazil and China. The relatively low level of biopesticide research in the EU (6880 ISI papers) versus the United States (18 839), India (9501) and China (7875) relates to the greater complexity of EU-based biopesticide regulations compared with these other countries. In this light, it is worth noting that tensions may exist between regulators that emphasise the beneficial nature of biopesticides in environmentally friendly crop management and those that adopt a more technologically based approach dependent on a chemical-pesticide-driven model. Compared with the other aforementioned countries, far fewer biopesticide products are available in the EU market, mainly as a direct result of the severe regulatory factors present there. The extent to which this trend will continue depends largely on a range of interacting political and/or regulatory decisions that influence environmentally friendly agricultural industries. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Mapping Fishing Effort through AIS Data

PubMed Central

Natale, Fabrizio; Gibin, Maurizio; Alessandrini, Alfredo; Vespe, Michele; Paulrud, Anton

2015-01-01

Several research initiatives have been undertaken to map fishing effort at high spatial resolution using the Vessel Monitoring System (VMS). An alternative to the VMS is represented by the Automatic Identification System (AIS), which in the EU became compulsory in May 2014 for all fishing vessels of length above 15 meters. The aim of this paper is to assess the uptake of the AIS in the EU fishing fleet and the feasibility of producing a map of fishing effort with high spatial and temporal resolution at European scale. After analysing a large AIS dataset for the period January-August 2014 and covering most of the EU waters, we show that AIS was adopted by around 75% of EU fishing vessels above 15 meters of length. Using the Swedish fleet as a case study, we developed a method to identify fishing activity based on the analysis of individual vessels’ speed profiles and produce a high resolution map of fishing effort based on AIS data. The method was validated using detailed logbook data and proved to be sufficiently accurate and computationally efficient to identify fishing grounds and effort in the case of trawlers, which represent the largest portion of the EU fishing fleet above 15 meters of length. Issues still to be addressed before extending the exercise to the entire EU fleet are the assessment of coverage levels of the AIS data for all EU waters and the identification of fishing activity in the case of vessels other than trawlers. PMID:26098430

Mapping Fishing Effort through AIS Data.

PubMed

Natale, Fabrizio; Gibin, Maurizio; Alessandrini, Alfredo; Vespe, Michele; Paulrud, Anton

2015-01-01

Several research initiatives have been undertaken to map fishing effort at high spatial resolution using the Vessel Monitoring System (VMS). An alternative to the VMS is represented by the Automatic Identification System (AIS), which in the EU became compulsory in May 2014 for all fishing vessels of length above 15 meters. The aim of this paper is to assess the uptake of the AIS in the EU fishing fleet and the feasibility of producing a map of fishing effort with high spatial and temporal resolution at European scale. After analysing a large AIS dataset for the period January-August 2014 and covering most of the EU waters, we show that AIS was adopted by around 75% of EU fishing vessels above 15 meters of length. Using the Swedish fleet as a case study, we developed a method to identify fishing activity based on the analysis of individual vessels' speed profiles and produce a high resolution map of fishing effort based on AIS data. The method was validated using detailed logbook data and proved to be sufficiently accurate and computationally efficient to identify fishing grounds and effort in the case of trawlers, which represent the largest portion of the EU fishing fleet above 15 meters of length. Issues still to be addressed before extending the exercise to the entire EU fleet are the assessment of coverage levels of the AIS data for all EU waters and the identification of fishing activity in the case of vessels other than trawlers.

Highly selective luminescent sensing of picric acid based on a water-stable europium metal-organic framework

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xia, Tifeng; Zhu, Fengliang; Cui, Yuanjing, E-mail: cuiyj@zju.edu.cn

A water-stable metal-organic framework (MOF) EuNDC has been synthesized for selective detection of the well-known contaminant and toxicant picric acid (PA) in aqueous solution. Due to the photo-induced electron transfer and self-absorption mechanism, EuNDC displayed rapid, selective and sensitive detection of PA with a detection limit of 37.6 ppb. Recyclability experiments revealed that EuNDC retains its initial luminescent intensity and same quenching efficiency in each cycle, suggesting high photostability and reusability for long-term sensing applications. The excellent detection performance of EuNDC makes it a promising PA sensing material for practical applications. - Graphical abstract: A water-stable europium-based metal-organic framework hasmore » been reported for highly selective sensing of picric acid (PA) with a detection limit of 37.6 ppb in aqueous solution. - Highlights: • A water-stable metal-organic framework (MOF) EuNDC was synthesized. • The highly selective detection of picric acid with a detection limit of 37.6 ppb was realized. • The detection mechanism were also presented and discussed.« less

The Center for Alternatives to Animal Testing - Europe (CAAT-EU): a transatlantic bridge for the paradigm shift in toxicology.

PubMed

Daneshian, Mardas; Leist, Marcel; Hartung, Thomas

2010-01-01

The Center for Alternatives to Animal Testing - Europe (CAAT-EU) was founded based collaboration between the Johns Hopkins Bloomberg School of Public Health and the University of Konstanz. CAAT-EU, housed at the University of Konstanz, will coordinate transatlantic activities to promote humane science in research and education, and participate, as partner or coordinator, in publicly and privately funded European projects. Thomas Hartung will serve as program liaison representing Johns Hopkins University and Marcel Leist as the University of Konstanz liaison. CAAT-EU aims to: 1) Set up transatlantic consortia for international research projects on alternative methods. 2) Establish a CAAT Europe faculty and advisory board composed of sponsor representatives and prominent academics from Europe . 3) Participate in the Transatlantic Think Tank for Toxicology (t4) devoted to conceptual work for the paradigm shift in toxicology. 4) Coordinate a series of information days in Europe on relevant developments in the US, similar to the 2009 series CAAT held in the US on EU issues (one on the 7th Amendment to the EU Cosmetics Directive and one on EU and US chemical regulation). 5) Support ALTEX as the official journal of CAAT and CAAT-EU. 6) Develop strategic projects with sponsors to promote humane science and new toxicology, especially with CAAT faculty members. 7) Develop a joint education program between Johns Hopkins and the University of Konstanz, such as e-courses and the existing Humane Science Certificate program developed by CAAT, a student exchange program, and collaboration with the International Graduate School "Cell-based Characterization of De- and Regeneration" in Konstanz.

Tailored white light emission in Eu3+/Dy3+ doped tellurite glass phosphors containing Al3+ ions

NASA Astrophysics Data System (ADS)

Walas, Michalina; Piotrowski, Patryk; Lewandowski, Tomasz; Synak, Anna; Łapiński, Marcin; Sadowski, Wojciech; Kościelska, Barbara

2018-05-01

Tellurite glass systems modified by addition of aluminum fluoride AlF3 have been successfully synthesized as host matrices for optically active rare earth ions RE3+ (RE3+ = Eu3+, Dy3+). Samples with different Eu3+ to Dy3+ molar ratio have been studied in order to determine possibility of white light emission via UV excitation. Structural investigations confirmed amorphous character of materials whereas spectroscopic studies brought more insight into glass network's nature. FTIR results shown presence of two features related to tellurite glass matrix (in 490-935 cm-1 spectral region) and another one (940-1250 cm-1) due to aluminum addition. Especially, Al-O and Te-O-Al bonds of AlO4 tetrahedrons have been found. AlO4 units are considered as glass formers that improve network's strength and thermal resistivity against devitrification. Based on XPS studies of Al3+ photoelectron band the existence of Al-O and also Al-F bonds have been examined. Moreover, signals originating from Eu3+ and Dy3+ have been found confirming their valence state. Luminescence results revealed possibility of simultaneous UV excitation of Eu3+ and Dy3+ ions. Excitation with λexc = 390 and 393 nm resulted in white light generation starting from warm white to neutral and cool white depending on Eu3+ concentration and used excitation wavelength. Additionally, increase of decay lifetime of Eu3+ induced by Al3+ presence have been revealed based on luminescence decay analysis. Thus, tellurite glass systems modified by AlF3 and doped with Eu3+/Dy3+ may be considered as promising candidates for white light emitting sources.

Competence-Based Blended Learning in Building Automation: Towards a EU Curriculum in "Domotica"

ERIC Educational Resources Information Center

Sommaruga, L.; De Angelis, E.

2007-01-01

A competence-based approach was applied to a blended learning on line distance training in the Euroinno EU project aimed at vocational training in building automation. The current paper describes the experience gathered during the learning process and the definition of the curriculum. A number of issues emerged during the sessions concerning…

UV-Vis-NIR luminescence properties and energy transfer mechanism of LiSrPO4:Eu2+, Pr3+ suitable for solar spectral convertor.

PubMed

Chen, Yan; Wang, Jing; Liu, Chunmeng; Tang, Jinke; Kuang, Xiaojun; Wu, Mingmei; Su, Qiang

2013-02-11

An efficient near-infrared (NIR) phosphor LiSrPO(4):Eu(2+), Pr(3+) is synthesized by solid-state reaction and systematically investigated using x-ray diffraction, diffuse reflection spectrum, photoluminescence spectra at room temperature and 3 K, and the decay curves. The UV-Vis-NIR energy transfer mechanism is proposed based on these results. The results demonstrate Eu(2+) can be an efficient sensitizer for harvesting UV photon and greatly enhancing the NIR emission of Pr(3+) between 960 and 1060 nm through efficient energy feeding by allowed 4f-5d absorption of Eu(2+) with high oscillator strength. Eu(2+)/Pr(3+) may be an efficient donor-acceptor pair as solar spectral converter for Si solar cells.

[Drugs in the European Union: the health-market complex].

PubMed

Antoñanzas, Fernando; Rodríguez, Roberto; Sacristán, José Antonio; Illa, Rafael

2005-01-01

To characterize the peculiar economic nature of the pharmaceutical market in the EU, to study potential groupings of countries based on several pharmaceutical variables, to analyze some recent regulations designed to create the single market, and to present some thoughts on the decision making process in public health from the perspective of current public health budgets. We performed an economic analysis of health and pharmaceutical macrovariables, cluster analysis, review of EU pharmaceutical and industrial regulations and review of pharmaceutical budgeting legislation in the member states. The pharmaceutical market of the EU was characterized and EU countries were classified into two principal groups according to 5 selected variables. EU regulations tend to promote R + D and drug production and thus the EU industrial sector is backed up. National regulations differ in terms of pricing and drugs reimbursement. The creation of a single market for drugs in the EU should take this regulatory diversity into account and seek equilibrium between economic factors and public health. This single market may be a dangerous strategy if it becomes a general dogma and even more so if deadlines are fixed and short.

The doping sites in Eu2+-doped AIBIIPO4 phosphors and their consequence on the photoluminescence excitation spectra

NASA Astrophysics Data System (ADS)

Amer, M.; Boutinaud, P.

2018-02-01

The energy corresponding to the excitation edge in Eu2+-doped phosphate phosphors of the type AIBIIPO4 (AI = monovalent cation, BII = divalent cation) is calculated from the knowledge of two crystal-structure-related factors he(X(i)) and Fc(X(i)) which are connected respectively to the crystal field splitting (CFS) and the centroid energy (Ec) of the excited 4f65d1 electron configuration of Eu2+. The calculation is carried out for each cation site X(i) available for Eu2+ in 25 different compositions of AIBIIPO4 including NaZnPO4-Eu2+ for which the luminescence is firstly reported. Our results indicate (1) that is it possible to identify the nature of the cation site that contributes to the excitation edge of Eu2+ in AIBIIPO4 within an accuracy of±1000 cm-1 and (2) that the method can be used as a tool for the predictive design of AIBIIPO4 - Eu2+ phosphors applicable in solid state LED-based lighting.

Influence of Gd3+ concentration on luminescence properties of Eu3+ ions in sol-gel materials

NASA Astrophysics Data System (ADS)

Szpikowska-Sroka, Barbara; Pawlik, Natalia; Pisarski, Wojciech A.

2016-12-01

The sol-gel powders doubly-doped with Gd3+/Eu3+ ions with different concentration of Gd3+ have been successfully obtained. The spectroscopic characterization of prepared samples was conducted based on excitation and emission spectra as well as luminescence decay analysis. Upon direct excitation of Eu3+ active ions, the characteristic 5D0 → 7F1 (orange) and 5D0 → 7F2 (red) emission bands were observed. The energy transfer from Gd3+ to Eu3+ ions was registered upon λexc = 273 nm excitation. An efficient conversion of ultraviolet radiation (UV) into visible luminescence was successfully observed. The energy transfer process from Gd3+ to Eu3+ led to longer luminescence decay from the 5D0 state in comparison to that obtained under direct excitation of Eu3+ ions (λexc = 393 nm). Generally, obtained results clearly indicated the beneficial influence of increasing concentration of Gd3+ ions on luminescence properties of Eu3+ in studied silica sol-gel phosphors.

Investigation of recovery and recycling of rare earth elements from waste fluorescent lamp phosphors

NASA Astrophysics Data System (ADS)

Eduafo, Patrick Max

Characterization techniques and experimental measurements were used to evaluate a process for recycling rare earth elements (REEs) from spent fluorescent lamp phosphors. QEMSCAN analysis revealed that over 60% of the rare earth bearing minerals was less than 10 microm. A representative sample of the as-received feed contained 14.59 wt% total rare earth elements (TREE) and upon sieving to below 75 microm, the grade increased to 19.60 wt% REE with 98.75% recovery. Based on experimental work, a new process for extracting the chief REEs from end of life fluorescent lamps has been developed. The proposed flowsheet employs a three-stage leaching and precipitation process for selective extraction and recovery of the REEs. Hydrochloric acid was used as lixiviant in batch leach experiments on the phosphor powder. The maximum extraction obtained was 100% for both yttrium and europium under the following leaching conditions: 2.5 M HCl, 70°C, 1 hour, 180 g/L and 600 rpm. However, the solubility of cerium, lanthanum and terbium remained low at these conditions. Kinetic data of the leaching of yttrium and europium showed best fit to the logarithmic rate expression of the empirical model of leaching. Activation energy was calculated to be 77.49 kJ/mol for Y and 72.75 kJ/mol for Eu in the temperature range of 298 to 343 K. Precipitation tests demonstrate that at least 50% excess the stoichiometric amount of oxalic acid is needed to recover yttrium and europium efficiently to produce a pure (Y, Eu) mixed oxide. Total recovery of the REEs was achieved even at very low pH or without any base added. Over 99% pure mixed rare earth oxide at 99% recovery has been attained. An economic assessment of the developed process using operating and capital cost have be undertaken and based on the analysis of the three economic scenarios, two are economic and one is non-economic.

Compliance with the annual NO 2 air quality standard in Athens. Required NO x levels and expected health implications

NASA Astrophysics Data System (ADS)

Chaloulakou, A.; Mavroidis, I.; Gavriil, I.

Recent risk assessment studies have shown that high outdoor NO 2 levels observed in residential areas contribute to increased respiratory and cardiovascular diseases and mortality. Detailed information on present NO 2 levels as well as predictions of NO 2 concentrations corresponding to reduced NO x levels in urban areas are very useful to decision and policy makers in order to protect the public health. In the present paper, monitoring stations of the Athens network are initially classified into two main groups, traffic affected and urban background, using effectively a criterion based on the ratio of annual mean NO:NO 2 concentrations. Two empirical methodologies are then considered and compared for assessing the effect of different NO x levels on the attainment of the annual NO 2 air quality standard at urban-background locations in the Athens area. An interesting finding is that these two methodologies, one more general and one both year and site dependent, give similar results for the specific study area and can be applied alternatively based on the length of available concentration time series. The results show that in order to meet the EU annual mean NO 2 objective at all the urban-background locations of the Athens area, annual NO x concentrations should be reduced to approximately 60 μg m -3, requiring NO x emission reductions of up to 30%. An analysis of the health implications of the currently observed NO 2 levels is conducted, based on a dose-response relationship, and is coupled with available health-related data for the Athens area. This analysis suggests that if NO 2 concentrations were reduced to the levels of the annual EU air quality standard, then a decrease of hospital admissions of up to 2.6% would be observed, depending on the levels of NO 2 measured at different monitoring sites of the Athens conurbation.

Uptake Mechanisms of Eu(III) on Hydroxyapatite: A Potential Permeable Reactive Barrier Backfill Material for Trapping Trivalent Minor Actinides.

PubMed

Xu, Lin; Zheng, Tao; Yang, Shitong; Zhang, Linjuan; Wang, Jianqiang; Liu, Wei; Chen, Lanhua; Diwu, Juan; Chai, Zhifang; Wang, Shuao

2016-04-05

The permeable reactive barrier (PRB) technique has attracted an increasing level of attention for the in situ remediation of contaminated groundwater. In this study, the macroscopic uptake behaviors and microscopic speciation of Eu(III) on hydroxyapatite (HAP) were investigated by a combination of theoretical modeling, batch experiments, powder X-ray diffraction (PXRD) fitting, and X-ray absorption spectroscopy (XAS). The underlying removal mechanisms were identified to further assess the application potential of HAP as an effective PRB backfill material. The macroscopic analysis revealed that nearly all dissolved Eu(III) in solution was removed at pH 6.5 within an extremely short reaction time of 5 min. In addition, the thermodynamic calculations, desorption experiments, and PXRD and XAS analyses definitely confirmed the formation of the EuPO4·H2O(s) phase during the process of uptake of dissolved Eu(III) by HAP via the dissolution-precipitation mechanism. A detailed comparison of the present experimental findings and related HAP-metal systems suggests that the relative contribution of precipitation to the total Eu(III) removal increases as the P:Eu ratio decreases. The dosage of HAP-based PRB for the remediation of groundwater polluted by Eu(III) and analogous trivalent actinides [e.g., Am(III) and Cm(III)] should be strictly controlled depending on the dissolved Eu(III) concentration to obtain an optimal P:M (M represents Eu, Am, or Cm) ratio and treatment efficiency.

Comparing pharmaceutical pricing and reimbursement policies in Croatia to the European Union Member States.

PubMed

Vogler, Sabine; Habl, Claudia; Bogut, Martina; Voncina, Luka

2011-04-15

To perform a comparative analysis of the pharmaceutical pricing and reimbursement systems in Croatia and the 27 European Union (EU) Member States. Knowledge about the pharmaceutical systems in Croatia and the 27 EU Member States was acquired by literature review and primary research with stakeholders. Pharmaceutical prices are controlled at all levels in Croatia, which is also the case in 21 EU Member States. Like many EU countries, Croatia also applies external price referencing, i.e., compares prices with other countries. While the wholesale remuneration by a statutorily regulated linear mark-up is applied in Croatia and in several EU countries, the pharmacy compensation for dispensing reimbursable medicines in the form of a flat rate service fee in Croatia is rare among EU countries, which usually apply a linear or regressive pharmacy mark-up scheme. Like in most EU countries, the Croatian Social Insurance reimburses specific medicines at 100%, whereas patients are charged co-payments for other reimbursable medicines. Criteria for reimbursement include the medicine's importance from the public health perspective, its therapeutic value, and relative effectiveness. In Croatia and in many EU Member States, reimbursement is based on a reference price system. The Croatian pharmaceutical system is similar to those in the EU Member States. Key policies, like external price referencing and reference price systems, which have increasingly been introduced in EU countries are also applied in Croatia and serve the same purpose: to ensure access to medicines while containing public pharmaceutical expenditure.

Prediction of population with Alzheimer's disease in the European Union using a system dynamics model.

PubMed

Tomaskova, Hana; Kuhnova, Jitka; Cimler, Richard; Dolezal, Ondrej; Kuca, Kamil

2016-01-01

Alzheimer's disease (AD) is a slowly progressing neurodegenerative brain disease with irreversible brain effects; it is the most common cause of dementia. With increasing age, the probability of suffering from AD increases. In this research, population growth of the European Union (EU) until the year 2080 and the number of patients with AD are modeled. The aim of this research is to predict the spread of AD in the EU population until year 2080 using a computer simulation. For the simulation of the EU population and the occurrence of AD in this population, a system dynamics modeling approach has been used. System dynamics is a useful and effective method for the investigation of complex social systems. Over the past decades, its applicability has been demonstrated in a wide variety of applications. In this research, this method has been used to investigate the growth of the EU population and predict the number of patients with AD. The model has been calibrated on the population prediction data created by Eurostat. Based on data from Eurostat, the EU population until year 2080 has been modeled. In 2013, the population of the EU was 508 million and the number of patients with AD was 7.5 million. Based on the prediction, in 2040, the population of the EU will be 524 million and the number of patients with AD will be 13.1 million. By the year 2080, the EU population will be 520 million and the number of patients with AD will be 13.7 million. System dynamics modeling approach has been used for the prediction of the number of patients with AD in the EU population till the year 2080. These results can be used to determine the economic burden of the treatment of these patients. With different input data, the simulation can be used also for the different regions as well as for different noncontagious disease predictions.

Suppression of Red Luminescence in Wire Explosion Derived Eu:ZnO

NASA Astrophysics Data System (ADS)

Pallavi, Bandi; Sathyan, Sneha; Yoshimura, Takuya; Kumar, Praveen; Anbalagan, Kousika; Talluri, Bhusankar; Ramanujam, Sarathi; Ranjan, Prem; Thomas, Tiju

2018-03-01

Europium oxide (Eu2O3) is coated on zinc (Zn) wire using the electrophoretic deposition process. The coated Zn wire is subjected to the wire explosion process (WEP) which is rapid (< 15 min), and chimie douce (soft chemical, low temperature), in nature; this results in the formation of Eu doped ZnO. The explosion chamber contains oxygen (99.9%) at atmospheric pressure. Electron micrographs indicate that the particle sizes are ˜ 80 nm. Diffractogram-based analysis suggests that the crystallite size is 18-20 nm in the as-prepared doped ZnO nanoparticles. Electron paramagnetic resonance shows the presence of Zn vacancies and the cryo-photoluminescence spectrum indicates that Eu exists in the + 3 state. A combined Williamson-Hall plot and Kisielowski's model based analysis indicates that Eu is a substitutional dopant in WEP derived Eu:ZnO particles. It is estimated that this material has ˜ 0.24 at.% doping. This analysis also shows that, unlike another popular material GaN, in the case of ZnO, Eu3+ strictly substitutes for Zn2+ (i.e., dopant replacing a cation-anion pair does not seem possible). It may be noted that Eu3+ in a suitable host is oftentimes reported to be an efficient luminophore. The IR spectra show a band shift from 486 cm-1 to 493 cm-1; with peak shifts from 436 cm-1 to 430 cm-1 in Raman spectra. These too indicate the presence of Eu in the samples. However, at room temperature, only green luminescence (centered at 534 nm) is observed from the sample indicating (1) high concentrations of OZn anti-site defects and Zn vacancies, and (2) concomitant quenching of the luminescence at room temperature. Our results suggest that WEP is viable for synthesizing rare earth doped ceramic materials. However, obtaining efficient phosphors using this approach will likely require, (1) reduction of defect densities, and (2) appropriate passivation using post-processing.

Changing the cost of care for chronic myeloid leukemia: the availability of generic imatinib in the USA and the EU.

PubMed

Conti, Rena M; Padula, William V; Larson, Richard A

2015-04-01

Imatinib is an oral tyrosine kinase inhibitor and considered to be the most successful targeted anti-cancer agent yet developed given its substantial efficacy in treating chronic myeloid leukemia (CML) and other malignant diseases. In the USA and the European Union (EU), Novartis' composition of matter patent on imatinib will expire in 2016. The potential impact on health system spending levels for CML after generic imatinib becomes available is the subject of significant interest among stakeholders. The extent of the potential savings largely depends on whether and to what extent prices decline and use stays the same or even increases. These are also empirical questions since the likely spending implications following generic imatinib's availability are predicated on multiple factors: physicians' willingness to prescribe generic imatinib, molecule characteristics, and health system priorities. This article discusses each of these issues in turn. We then review their implications for the development of country-specific cost-effectiveness models to predict the implications for cost and quality of care from generic imatinib.

Changing the cost of care for chronic myeloid leukemia: the availability of generic imatinib in the USA and the EU

PubMed Central

Padula, William V.; Larson, Richard A.

2015-01-01

Imatinib is an oral tyrosine kinase inhibitor and considered to be the most successful targeted anti-cancer agent yet developed given its substantial efficacy in treating chronic myeloid leukemia (CML) and other malignant diseases. In the USA and the European Union (EU), Novartis’ composition of matter patent on imatinib will expire in 2016. The potential impact on health system spending levels for CML after generic imatinib becomes available is the subject of significant interest among stakeholders. The extent of the potential savings largely depends on whether and to what extent prices decline and use stays the same or even increases. These are also empirical questions since the likely spending implications following generic imatinib’s availability are predicated on multiple factors: physicians’ willingness to prescribe generic imatinib, molecule characteristics, and health system priorities. This article discusses each of these issues in turn. We then review their implications for the development of country-specific cost-effectiveness models to predict the implications for cost and quality of care from generic imatinib. PMID:25814091

X-ray excitation fluorescence spectra of the Eu2+-stabilized VK center in alkaline-earth fluoride mixed-crystal systems

NASA Astrophysics Data System (ADS)

Kawano, K.; Ohya, T.; Tsurumi, T.; Katoh, K.; Nakata, R.

1999-11-01

X-ray excitation fluorescence spectra were investigated for MF2:Eu (M=Ca, Sr, and Ba) and their mixed-crystal systems, Ca1-xSrxF2 and Sr1-xBaxF2 with the same fluorite structure. The UV recombination fluorescence band of the VK center associated with blue emission due to the f-d transition of Eu2+ ions was observed with changing mixture ratios x at room temperature. Two sets of weak spectra due to f-f transitions of Eu3+ ions also appeared in the 500-600-nm wavelength region. The peak wavelengths and the integrated intensities of the observed fluorescence were investigated as a function of the Eu concentration as well as the mixture ratio. For the blue emission of Eu2+, pulsed x-ray excitation resulted in shorter lifetimes (500-800 ns) than optical excitation, suggesting energy transfers between the excited states of VK centers and Eu2+. A kinematical fluorescence mechanism was proposed, taking into account the formation of a close pair of a hopping VK center and an immobile Eu2+ ion followed by an energy transfer from the former to the latter. Based on the calculated fluorescence decay curves best fitted to the response curves by x-ray pulse excitation, the energy transfer rates from VK centers to Eu2+ were estimated.

Defects Induced Enhancement of Eu3+ Emission in Yttria ( Y2O3:Eu3+)

NASA Astrophysics Data System (ADS)

Jagannathan, R.; Kutty, T.; Kottaisamy, M.; Jeyagopal, P.

1994-11-01

Bixbyite type Y2O3:Eu3+ apart from being the efficient red phosphor extensively used in trichromatic fluorescent lamps, it is a typical system one can apply Jørgensen's refined electron spin pairing theory. This can be used to explain the enhancement in Eu3+ emission intensity observed with the aliovalent substitution in the yttria host matrix. Results based on these are explained qualitatively by considering a simple configurational coordinate model. Futhermore, an insight into the different types of defects induced with the aliovalent substitution in the yttria lattice has become possible with EPR probe.

Highly selective luminescent sensing of picric acid based on a water-stable europium metal-organic framework

NASA Astrophysics Data System (ADS)

Xia, Tifeng; Zhu, Fengliang; Cui, Yuanjing; Yang, Yu; Wang, Zhiyu; Qian, Guodong

2017-01-01

A water-stable metal-organic framework (MOF) EuNDC has been synthesized for selective detection of the well-known contaminant and toxicant picric acid (PA) in aqueous solution. Due to the photo-induced electron transfer and self-absorption mechanism, EuNDC displayed rapid, selective and sensitive detection of PA with a detection limit of 37.6 ppb. Recyclability experiments revealed that EuNDC retains its initial luminescent intensity and same quenching efficiency in each cycle, suggesting high photostability and reusability for long-term sensing applications. The excellent detection performance of EuNDC makes it a promising PA sensing material for practical applications.

A single-phase Ba{sub 9}Lu{sub 2}Si{sub 6}O{sub 24}:Eu{sup 2+}, Ce{sup 3+}, Mn{sup 2+} phosphor with tunable full-color emission for NUV-based white LED applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Changhua; Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201; Liu, Yongfu, E-mail: liuyongfu@nimte.ac.cn

Highlights: • A single phase Ba{sub 9}Lu{sub 2}Si{sub 6}O{sub 24}:Eu{sup 2+}, Ce{sup 3+}, Mn{sup 2+} phosphor with full-color emission was obtained by solid-state reactions. • Eu{sup 2+}, Ce{sup 3+}, and Mn{sup 2+} acts as blue, green, and red luminescence centers, respectively. • The BLS:Eu{sup 2+}, Ce{sup 3+}, Mn{sup 2+} phosphor shows a high quantum efficient of ∼62% and a good color stability. • Combining this single phosphor with a 395 nm NUV-chip, an ideal white LED with a high CRI of 85 and a CCT of 6300 K was obtained. - Abstract: We obtained a single phase BLS:Eu{sup 2+}, Ce{supmore » 3+}, Mn{sup 2+} phosphor by solid-state reactions. Eu{sup 2+}, Ce{sup 3+}, and Mn{sup 2+} gives rise to the blue, green, and red emission, respectively. The Mn{sup 2+} red emission can be effectively enhanced via energy transfers from both Eu{sup 2+} and Ce{sup 3+}. Thus a tunable full color emission from 410 to 750 nm was realized in this single phosphor. The Eu{sup 2+} → Mn{sup 2+} energy transfer mechanism was investigated by the fluorescence decay curves. This single phosphor exhibits an efficient excitation band covering from 390 to 410 nm, which matches well with the emission light of the efficient NUV chips. The optimized BLS:Eu{sup 2+}, Ce{sup 3+}, Mn{sup 2+} phosphor shows a high quantum efficient of ∼62% and a good color stability. When this single phosphor was combined with a 395 nm NUV-chip, an ideal white LED with a high color render index (CRI) of 85 and a correlated color temperature (CCT) of 6300 K was obtained. This demonstrates the promising application of the BLS:Eu{sup 2+}, Ce{sup 3+}, Mn{sup 2+} single phosphor for the NUV-based white LEDs.« less

Assessing potential impacts of the EVFTA on Vietnam's pharmaceutical imports from the EU: an application of SMART analysis.

PubMed

Vu, Huong Thanh

2016-01-01

This paper by adopting the Software on Market Analysis and Restrictions on Trade assessed the ex-ante impact of tariff elimination under the European-Vietnam free trade agreement (EVFTA) on Vietnam's pharmaceutical imports from the EU based on two scenarios. The results showed that although Vietnam's tariff removal for the EU's medicines would not result in a significant increase in Vietnam's imports from the EU, Vietnam's deeper integration with ASEAN + 3 and TPP (the Trans-Pacific Partnership) nations would affect quite slightly on its imports from the EU. Therefore, the EU would be still the most important and biggest source of pharmaceuticals for Vietnam in the near future. In addition, there might be an uneven distribution in Vietnam's import increases by the EU nation, pharmaceutical group and product. The simulation results also pointed out that the EVFTA's trade creation effect would be higher than trade diversion effect and therefore the agreement would improve welfare of Vietnam. When Vietnam extends its coverage of tariff elimination to also TPP and ASEAN + 3, Vietnam's welfare would potentially increase more but Vietnam would face with the relatively high increases of pharmaceutical imports from not only the EU but also the US, Australia, South Korea, Thailand and China. Bases on these results, the paper argued that both the Vietnamese government and pharmaceutical enterprises should not neglect the EVFTA and its impacts on the pharmaceutical sector, and perceive clearly the uneven distribution of Vietnam's import changes from the EU by nation and by product to design appropriate business and investment strategy. In addition, Vietnam should take measures to diversify its European import markets to be less dependent on the traditional ones in the current context of the EU. Finally, Vietnam should promote the integration in the pharmaceutical sector with all three groups of nations, especially ASEAN and ASEAN's key partners, to reduce trade diversion effect and raise the welfare of Vietnam, given that Vietnam should consider carefully the point of time to remove tariff for each group to avoid the sudden increase in its pharmaceutical imports.

Influence of 6s{sup 2} lone pair electrons of Bi{sup 3+} on its preferential site occupancy in fluorapatite, NaCa{sub 3}Bi(PO{sub 4}){sub 3}F – An insight from Eu{sup 3+} luminescent probe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lakshminarasimhan, N., E-mail: nlnsimha@gmail.com; Varadaraju, U.V.

2014-12-15

Graphical abstract: Eu{sup 3+} structural probe – difference in Eu{sup 3+} PL emission in (a) NaCa{sub 3}Bi{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F and (b) NaCa{sub 3}La{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F suggests Bi{sup 3+} with preferential site occupancy at M(II) site directing Eu{sup 3+} to M(I) site. - Highlights: • Eu{sup 3+} luminescent probe used for establishing the role of 6s{sup 2} lone pair electrons of Bi{sup 3+} in fluorapatite. • Difference in Eu{sup 3+} PL emission spectral features in NaCa{sub 3}Bi{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F and NaCa{sub 3}La{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F. • Preferential site occupancy of Bi{sup 3+} in M(II)more » site directs Eu{sup 3+} to M(I) site in NaCa{sub 3}Bi{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F. - Abstract: Eu{sup 3+} luminescence was used as a structural probe in understanding the preferential site occupancy of lone pair cation, Bi{sup 3+}, in fluorapatite by comparing the photoluminescence (PL) emission spectral features with that of in analogous La{sup 3+} based fluorapatite. The fluorapatites, NaCa{sub 3}Bi{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F and NaCa{sub 3}La{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F, were synthesized by conventional high temperature solid state reaction method and characterized by powder X-ray diffraction (XRD) and FT-IR spectroscopy. The Eu{sup 3+} PL results revealed a difference in the emission spectral features in NaCa{sub 3}Bi{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F and NaCa{sub 3}La{sub 0.95}Eu{sub 0.05}(PO{sub 4}){sub 3}F. This difference in Eu{sup 3+} PL emission can be attributed to the difference in its site occupancy in the studied fluorapatites.« less

Reddish-orange, neutral and warm white emissions in Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses

NASA Astrophysics Data System (ADS)

Rodríguez-Carvajal, David A.; Meza-Rocha, A. N.; Caldiño, U.; Lozada-Morales, R.; Álvarez, E.; Zayas, Ma. E.

2016-11-01

Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses were prepared using the melt-quenching process and analyzed by X-diffraction, Raman spectroscopy, excitation and emission spectra, and emission decay time profiles. The lack of X ray diffraction peaks revealed that all samples are amorphous. Vibrational modes associated with Tesbnd Osbnd Te and Gesbnd Osbnd Ge related bonds and molecular oxygen were detected by Raman spectroscopy. The luminescence characteristics were studied upon excitations that correspond with the emission of InGaN (370-420 nm) based LEDs. The Eu3+ singly doped glass displayed reddish-orange global emission, with x = 0.601 and y = 0.349 CIE1931 chromaticity coordinates, upon 393 nm excitation. Neutral emission with x = 0.373 and y = 0.412 CIE1931 chromaticity coordinates and correlated color temperature (CCT) of 4400 K, was achieved in the Dy3+ singly doped glass excited at 388 nm. The Dy3+/Eu3+ co-doped glass exhibited warm, neutral and soft warm white emissions with CCT values of 3435, 4153 and 2740 K, under excitations at 382, 388 and 393 nm, respectively, depending mainly on the Dy3+ and Eu3+ relative excitation. The Dy3+ excitation bands observed in the Dy3+/Eu3+ glass by monitoring the 611 nm Eu3+ emission, suggest that Dy3+ → Eu3+ energy transfer takes place, despite the fact that the Dy3+ emission decays in the Dy3+ and Dy3+/Eu3+ doped glass, remain without changes. The shortening of Eu3+ decay in presence of Dy3+ was attributed to an Eu3+ → Dy3+ non-radiative energy transfer process, which according with the Inokuti-Hirayama model might be dominated through an electric quadrupole-quadrupole interaction, with efficiency and probability of 5.5% and 51.6 s-1, respectively.

Separation of Trivalent Actinides from Lanthanides Using a Capillary Electrophoresis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mori, Tomotaka; Ishii, Yasuo; Hayashi, Kazunori

2007-07-01

A separation of {sup 241}Am(III) from {sup 152,154}Eu(III) was carried out using a capillary electrophoresis technique in a mixed solvent (CH{sub 3}OH/H{sub 2}O) system containing thiocyanate ion. First, the formation constants ({beta}{sub n}) between thiocyanate ion and Eu(III) or Am(III) were investigated in the mixed solvent solutions by a back-extraction technique using bis (2-ethylhexyl) hydrogen phosphate-toluene. The mean charges calculated on the basis of the data of {beta}{sub n} for Eu(III) were comparatively higher than those for Am(III). Based on the differences between the mean charges of Eu(III) and Am(III), separations for Am(III)/Eu(III) by means of capillary electrophoresis technique weremore » tried in the (H{sup +}, Na{sup +})(SCN{sup -}, ClO{sub 4}{sup -}) mixed solvent solutions. It was proved that Am(III) was completely separated from Eu(III). (authors)« less

Synchrotron powder X-ray diffraction and structural analysis of Eu0.5La0.5FBiS2-x Se x

NASA Astrophysics Data System (ADS)

Nagasaka, K.; Jinno, G.; Miura, O.; Miura, A.; Moriyoshi, C.; Kuroiwa, Y.; Mizuguchi, Y.

2017-07-01

Eu0.5La0.5FBiS2-x Se x is a new BiS2-based superconductor system. In Eu0.5La0.5FBiS2-x Se x , electron carriers are doped to the BiS2 layer by the substitution of Eu by La. Bulk superconductivity in this system is induced by increasing the in-plane chemical pressure, which is controlled by the Se concentration (x). In this study, we have analysed the crystal structure of Eu0.5La0.5FBiS2-x Se x using synchrotron powder diffraction and the Rietveld refinement. The precise determination of the structural parameters and thermal factors suggest that the emergence of bulk superconductivity in Eu0.5La0.5FBiS2-x Se x is achieved by the enhanced in-plane chemical pressure and the decrease in in-plane disorder.

pH-sensitive fluorescent sensors based on europium(III) complexes.

PubMed

Zhang, Xiaolin; Jiao, Yang; Jing, Xu; Wu, Hongmei; He, Guangjie; Duan, Chunying

2011-03-21

New europium(III) complexes Eu(TTA)(2)-DSQ and Eu(TTA)(3)-DR1 were designed and synthesized as new fluorescent pH probes (where HDSQ = 5-(dimethylamino)-N-(4-(2-((8-hydroxyquinolin-2-yl)methylene)hydrazinecarbonyl)phenyl)naphthalene-1-sulfonamide, DR1 = N(1)-(4-(dimethylamino)benzylidene)-N(2)-(rhodamine-6G) lactamethylene-diamine and TTA = thiophentrifluoroacetone). Eu(TTA)(2)-DSQ exhibited high sensitivity in monitoring pH changes in neutral aqueous solution with negligible background fluorescence. Eu(TTA)(3)-DR1 comprised a green light emitting Rhodamine 6G fluorophore and a Eu(III) moiety as the origin of red light. These pH-sensitive emitter components have pK(a) values of 5.0 and 7.2 respectively, and exhibit isolated protonated steps within one molecule. Luminescence titrations demonstrate that Eu(TTA)(3)-DR1 was able to detect pH values at both near neutral pH and acidic pH ranges, and was also able to detect pH in both cultured cells and in vivo.

Europium (III) Organic Complexes in Porous Boron Nitride Microfibers: Efficient Hybrid Luminescent Material

NASA Astrophysics Data System (ADS)

Lin, Jing; Feng, Congcong; He, Xin; Wang, Weijia; Fang, Yi; Liu, Zhenya; Li, Jie; Tang, Chengchun; Huang, Yang

2016-09-01

We report the design and synthesis of a novel kind of organic-inorganic hybrid material via the incorporation of europium (III) β-diketonate complexes (Eu(TTA)3, TTA = 2-thenoyltrifluoroacetone) into one-dimensional (1D) porous boron nitride (BN) microfibers. The developed Eu(TTA)3@BN hybrid composites with typical 1D fibrous morphology exhibit bright visible red-light emission on UV illumination. The confinement of Eu(TTA)3 within pores of BN microfibers not only decreases the aggregation-caused quenching in solid Eu(TTA)3, but also improves their thermal stabilities. Moreover, The strong interactions between Eu(TTA)3 and porous BN matrix result in an interesting energy transfer process from BN host to TTA ligand and TTA ligand to Eu3+ ions, leading to the remarkable increase of red emission. The synthetic approach should be a very promising strategy which can be easily expanded to other hybrid luminescent materials based on porous BN.

Europium (III) Organic Complexes in Porous Boron Nitride Microfibers: Efficient Hybrid Luminescent Material

PubMed Central

Lin, Jing; Feng, Congcong; He, Xin; Wang, Weijia; Fang, Yi; Liu, Zhenya; Li, Jie; Tang, Chengchun; Huang, Yang

2016-01-01

We report the design and synthesis of a novel kind of organic-inorganic hybrid material via the incorporation of europium (III) β-diketonate complexes (Eu(TTA)3, TTA = 2-thenoyltrifluoroacetone) into one-dimensional (1D) porous boron nitride (BN) microfibers. The developed Eu(TTA)3@BN hybrid composites with typical 1D fibrous morphology exhibit bright visible red-light emission on UV illumination. The confinement of Eu(TTA)3 within pores of BN microfibers not only decreases the aggregation-caused quenching in solid Eu(TTA)3, but also improves their thermal stabilities. Moreover, The strong interactions between Eu(TTA)3 and porous BN matrix result in an interesting energy transfer process from BN host to TTA ligand and TTA ligand to Eu3+ ions, leading to the remarkable increase of red emission. The synthetic approach should be a very promising strategy which can be easily expanded to other hybrid luminescent materials based on porous BN. PMID:27687246

Intermediate-valence state of the Sm and Eu in SmB6 and EuCu2Si2: neutron spectroscopy data and analysis

NASA Astrophysics Data System (ADS)

Savchenkov, P. S.; Alekseev, P. A.; Podlesnyak, A.; Kolesnikov, A. I.; Nemkovski, K. S.

2018-02-01

Magnetic neutron scattering data for Sm (SmB6, Sm(Y)S) and Eu (EuCu2Si2-x Ge x ) intermediate-valence compounds have been analysed in terms of a generalized model of the intermediate-radius exciton. Special attention is paid to the correlation between the average ion’s valence and parameters of the low-energy excitation in the neutron spectra, such as the resonance mode, including its magnetic form factor. Along with specific features of the formation of the intermediate-valence state for Sm and Eu ions, common physical mechanisms have been revealed for systems based on these elements from the middle of the rare-earth series. A consistent description of the existing experimental data has been obtained by using the concept of a loosely bound hole for the Eu f-electron shell in the intermediate-valence state, in analogy with the previously established loosely bound electron model for the Sm ion.

The implementation of the Strategy Europe 2020 objectives in European Union countries: the concept analysis and statistical evaluation.

PubMed

Stec, Małgorzata; Grzebyk, Mariola

2018-01-01

The European Union (EU), striving to create economic dominance on the global market, has prepared a comprehensive development programme, which initially was the Lisbon Strategy and then the Strategy Europe 2020. The attainment of the strategic goals included in the prospective development programmes shall transform the EU into the most competitive economy in the world based on knowledge. This paper presents a statistical evaluation of progress being made by EU member states in meeting Europe 2020. For the basis of the assessment, the authors proposed a general synthetic measure in dynamic terms, which allows to objectively compare EU member states by 10 major statistical indicators. The results indicate that most of EU countries show average progress in realisation of Europe's development programme which may suggest that the goals may not be achieved in the prescribed time. It is particularly important to monitor the implementation of Europe 2020 to arrive at the right decisions which will guarantee the accomplishment of the EU's development strategy.

Properties of jet engine combustion particles during the PartEmis experiment. Hygroscopic growth at supersaturated conditions

NASA Astrophysics Data System (ADS)

Hitzenberger, R.; Giebl, H.; Petzold, A.; Gysel, M.; Nyeki, S.; Weingartner, E.; Baltensperger, U.; Wilson, C. W.

2003-07-01

During the EU Project PartEmis, the microphysical properties of aircraft combustion aerosol were investigated. This study is focused on the ability of exhaust aerosols to act as cloud condensation nuclei (CCN). The combustor was operated at two different conditions representing old and modern aircraft engine technology. CCN concentrations were measured with the University of Vienna CCN counter [ Giebl et al., 2002] at supersaturations around 0.7%. The activation ratio (fraction of CCN in total aerosol) depended on the fuel sulphur content (FSC) and also on the operation conditions. CCN/CN ratios increased from 0.93 through 1.43 to 5.15 . 10-3 (old cruise conditions) and 0.67 through 3.04 to 7.94 . 10-3 (modern cruise conditions) when FSC increased from 50 through 410 to1270 μg/g. The activation behaviour was modelled using classical theories and with a semi-empirical model [ Gysel et al., 2003] based on measured hygroscopicity of the aerosol under subsaturated conditions, which gave the best agreement.

Enhanced electric dipole transition in lanthanide complex with organometallic ruthenocene units.

PubMed

Hasegawa, Yasuchika; Sato, Nao; Hirai, Yuichi; Nakanishi, Takayuki; Kitagawa, Yuichi; Kobayashi, Atsushi; Kato, Masako; Seki, Tomohiro; Ito, Hajime; Fushimi, Koji

2015-05-21

Enhanced luminescence of a lanthanide complex with dynamic polarization of the excited state and molecular motion is introduced. The luminescent lanthanide complex is composed of one Eu(hfa)3 (hfa, hexafluoroacetylacetonate) and two phosphine oxide ligands with ruthenocenyl units Rc, [Eu(hfa)3(RcPO)2] (RcPO = diphenylphosphorylruthenocene). The ruthenocenyl units in the phosphine oxide ligands play an important role of switching for dynamic molecular polarization and motion in liquid media. The oxidation states of the ruthenocenyl unit (Rc(1+)/Rc(1+)) are controlled by potentiostatic polarization. Eu(III) complexes attached with bidentate phosphine oxide ligands containing ruthenocenyl units, [Eu(hfa)3(RcBPO)] (RcBPO = 1,1'-bis(diphenylphosphoryl)ruthenocene), and with bidentate phosphine oxide ligands, [Eu(hfa)3(BIPHEPO)] (BIPHEPO =1,1'-biphenyl-2,2'-diylbis(diphenylphosphine oxide), were also prepared as references. The coordination structures and electrochemical properties were analyzed using single crystal X-ray analysis, cyclic voltammetry, and absorption spectroscopy measurements. The luminescence properties were estimated using an optoelectrochemical cell. Under potentiostatic polarization, a significant enhancement of luminescence was successfully observed for [Eu(hfa)3(RcPO)2], while no spectral change was observed for [Eu(hfa)3(RcBPO)]. In this study, the remarkable enhanced luminescence phenomena of Eu(III) complex based on the dynamic molecular motion under potentiostatic polarization have been performed.

The Effect of Eu Doping on Microstructure, Morphology and Methanal-Sensing Performance of Highly Ordered SnO2 Nanorods Array

PubMed Central

Zhao, Yanping; Li, Yuehua; Ren, Xingping; Gao, Fan; Zhao, Heyun

2017-01-01

Layered Eu-doped SnO2 ordered nanoarrays constructed by nanorods with 10 nm diameters and several hundred nanometers length were synthesized by a substrate-free hydrothermal route using alcohol and water mixed solvent of sodium stannate and sodium hydroxide at 200 °C. The Eu dopant acted as a crystal growth inhibitor to prevent the SnO2 nanorods growth up, resulting in tenuous SnO2 nanorods ordered arrays. The X-ray diffraction (XRD) revealed the tetragonal rutile-type structure with a systematic average size reduction and unit cell volume tumescence, while enhancing the residual strain as the Eu-doped content increases. The surface defects that were caused by the incorporation of Eu ions within the surface oxide matrix were observed by high-resolution transmission electron microscope (HRTEM). The results of the response properties of sensors based on the different levels of Eu-doped SnO2 layered nanoarrays demonstrated that the 0.5 at % Eu-doped SnO2 layered nanorods arrays exhibited an excellent sensing response to methanal at 278 °C. The reasons of the enhanced sensing performance were discussed from the complicated defect surface structure, the large specific surface area, and the excellent catalytic properties of Eu dopant. PMID:29168796

Effect of Eu magnetism on the electronic properties of the candidate Dirac material EuMnBi2

NASA Astrophysics Data System (ADS)

May, Andrew F.; McGuire, Michael A.; Sales, Brian C.

2014-08-01

The crystal structure and physical properties of the layered material EuMnBi2 have been characterized by measurements on single crystals. EuMnBi2 is isostructural with the Dirac material SrMnBi2 based on single-crystal x-ray diffraction, crystallizing in the I4/mmm space group (No. 139). Magnetic susceptibility measurements suggest antiferromagnetic (AFM) ordering of moments on divalent Eu ions near TN=22 K. For low fields, the ordered Eu moments are aligned along the c axis, and a spin flop is observed near 5.4 T at 5 K. The moment is not saturated in an applied field of 13 T at 5 K, which is uncommon for compounds containing Eu2+. The magnetic behavior suggests an anisotropy enhancement via interaction between Eu and the Mn moments that appear to be ordered antiferromagnetically below ≈310 K. A large increase in the magnetoresistance is observed across the spin flop, with absolute magnetoresistance reaching ≈650% at 5 K and 12 T. Hall effect measurements reveal a decrease in the carrier density below TN, which implies a manipulation of the Fermi surface by magnetism on the sites surrounding the Bi square nets that lead to Dirac cones in this family of materials.

A novel greenish yellow-orange red Ba3Y4O9:Bi(3+),Eu(3+) phosphor with efficient energy transfer for UV-LEDs.

PubMed

Li, Kai; Lian, Hongzhou; Shang, Mengmeng; Lin, Jun

2015-12-21

A series of novel color-tunable Ba3Y4O9:Bi(3+),Eu(3+) phosphors were prepared for the first time via the high-temperature solid-state reaction route. The effect of Bi(3+) concentration on the emission intensity of Ba3Y4O9:Bi(3+) was investigated. The emission spectra of the Ba3Y4O9:Bi(3+),Eu(3+) phosphors present both a greenish yellow band of Bi(3+) emission centered at 523 nm, and many characteristic emission lines of Eu(3+), derived from the allowed (3)P1-(1)S0 transition of the Bi(3+) ion and the (5)D0-(7)FJ transition of the Eu(3+) ion, respectively. The energy transfer phenomenon from Bi(3+) to Eu(3+) ions is observed under UV excitation in Bi(3+), Eu(3+) co-doped Ba3Y4O9 phosphors, and their transfer mechanism is demonstrated to be a resonant type via dipole-quadrupole interaction. The critical distance between Bi(3+) and Eu(3+) for the energy transfer effect was calculated via the concentration quenching and spectral overlap methods. Results show that color tuning from greenish yellow to orange red can be realized by adjusting the mole ratio of Bi(3+) and Eu(3+) concentrations based on the principle of energy transfer. Moreover, temperature-dependent PL properties, CIE chromaticity coordinates and quantum yields of Ba3Y4O9:Bi(3+),Eu(3+) phosphors were also supplied. It is illustrated that the as-prepared Ba3Y4O9:Bi(3+),Eu(3+) phosphors can be potential candidates for color-tunable phosphors applied in UV-pumped LEDs.

Host composition dependent tunable multicolor emission in the single-phase Ba2(Ln(1-z)Tb(z))(BO3)2Cl:Eu phosphors.

PubMed

Xia, Zhiguo; Zhuang, Jiaqing; Meijerink, Andries; Jing, Xiping

2013-05-14

A new strategy based on the host composition design has been adopted to obtain efficient color-tunable emission from Ba2Ln(0.97-z)Tb(z)(BO3)2Cl:0.03Eu (Ln = Y, Gd and Lu, z = 0-0.97) phosphors. This study reveals that the single-phase Ba2Ln(1-z)Tb(z)(BO3)2Cl compounds can be applied to use allowed Eu(2+) absorption transitions to sensitize Eu(3+) emission via the energy transfer Eu(2+) → (Tb(3+))n → Eu(3+). The powder X-ray diffraction (XRD) and Rietveld refinement analysis shows single-phase Ba2Ln(1-z)Tb(z)(BO3)2Cl. As-prepared Ba2Ln(0.97-z)Tb(z)(BO3)2Cl:0.03Eu phosphors show intense green, yellow, orange and red emission under 377 nm near ultraviolet (n-UV) excitation due to a variation in the relative intensities of the Eu(2+), Tb(3+) and Eu(3+) emission depending on the Tb content (z) in the host composition, allowing color tuning. The variation in emission color is explained by energy transfer and has been investigated by photoluminescence and lifetime measurements and is further characterized by the Commission Internationale de l'éclairage (CIE) chromaticity indexes. The quantum efficiencies of the phosphors are high, up to 74%, and show good thermal stabilities up to 150 °C. This investigation demonstrates the possibility to sensitize Eu(3+) line emission by Eu(2+)via energy migration over Tb(3+) resulting in efficient color tunable phosphors which are promising for use in solid-state white light-emitting diodes (w-LEDs).

How online sales and promotion of snus contravenes current European Union legislation.

PubMed

Peeters, Silvy; Gilmore, Anna B

2013-07-01

The European Union (EU) Tobacco Products Directive that bans sales of snus (a form of oral tobacco) in EU countries other than Sweden is currently under review. Major tobacco companies favour the ban being overturned. This study aims to explore compliance with the current ban on snus sales and examines the conduct of online snus vendors, including their compliance with two other EU Directives on excise and tobacco advertising and Swedish legislation banning sales of snus outside Sweden. To determine who is currently distributing snus via the internet in the EU, searches were carried out in Google, followed by searches in the WHOIS and Amadeus databases. Five online test purchases of snus were made in each of 10 EU Member States using a standardised protocol. Feedback from the test purchases and further analysis of the websites accessed for test purchases were used to critically examine snus retailers' conduct. The majority of online vendors operate from Sweden and target non-Swedish EU citizens. Test purchases were successfully made in all 10 EU Member States; of 43 orders placed, only two failed. Age verification relied only on self-report. The majority of sales applied Swedish taxes, contrary to EU requirements. Copious sales promotion activities, many price based, are incorporated in these websites contravening the EU regulation, and three test purchases were delivered with gifts. Snus is currently being sold on the single market via the internet in contravention of Swedish legislation and three EU Directives. The apparent willingness of the tobacco industry to contravene EU and Swedish legislation and profit from unlawful sales raises questions about their status as stakeholders in consultations on future policy developments. The findings highlight how national and regional tobacco control legislation can be undermined in an increasingly globalised world.

Clinical trial designs to obtain marketing authorization of drugs for haematological malignancy in Japan, the EU and the US.

PubMed

Nagai, Sumimasa; Ozawa, Keiya

2016-07-01

Differences in regulatory actions between Japan, the European Union (EU) and the United States (US) regarding the approval date and primary endpoints of pivotal trials have never been analysed comprehensively. This study aimed to examine such differences in haematological malignancy indications not only in applications for new molecular entity agents but also in supplemental applications for additional indications. A total of 101 haematological malignancy indications were examined for 58 drugs. Only 30 indications were approved by the regulatory agencies of all three regions with 25, 9 and 67 indications being first approved in Japan, the EU and the US, respectively. Regarding the 18 indications approved only in the US, 13 were approved based on results of single-arm trials. The approval of all nine indications approved first in the EU was based on results of comparative trials. The primary endpoints were different between the EU and the US in 4 of 49 indications approved by both regulatory agencies, all of which were approved earlier in the US than in the EU. This analysis shows that the US Food and Drug Administration has taken the most active attitude to acceptance of surrogate endpoints in single-arm trials. Therefore, not only shorter review time but also this attitude may lead to earlier approval in US. © 2016 John Wiley & Sons Ltd.

Enhancing the role of science in the decision-making of the European Union.

PubMed

Allio, Lorenzo; Ballantine, Bruce; Meads, Richard

2006-02-01

Used well, science provides effective ways of identifying potential risks, protecting citizens, and using resources wisely. It enables government decisions to be based on evidence and provides a foundation for a rule-based framework that supports global trade. To ensure that the best available science becomes a key input in the decisions made by EU institutions, this abridged version of a working paper produced for the European Policy Centre, a leading, independent think tank, considers how science is currently used in the policy and decision-making processes of the EU, what the limitations of scientific evidence are, and how a risk assessment process based on scientific 'good practices' can be advantageous. Finally, the paper makes recommendations on how to improve the use of science by EU institutions.

Evaluation of pristine and Eu ₂O₃-added MgB ₂ ceramics for medical applications: hardness, corrosion resistance, cytotoxicity and antibacterial activity.

PubMed

Batalu, Dan; Stanciuc, Ana Maria; Moldovan, Lucia; Aldica, Gheorghe; Badica, Petre

2014-09-01

Nano- or micropowders of Eu2O3 were added to MgB2, resulting in a composition of (MgB2)0.975(EuO1.5)0.025. Pristine and doped samples were prepared using spark plasma sintering and tested for (i) Vickers hardness, (ii) pH evolution in phosphate-buffered saline solution, (iii) corrosion resistance (Tafel polarization curves), (iv) cytotoxicity (in vitro tests), and (v) antibacterial activity. Eu2O3 addition influenced the investigated properties. Solutions of MgB2-based samples show a relatively high saturation pH of 8.5. This value is lower than that of solutions incubated with Mg or other Mg-based biodegradable alloys reported in the literature. MgB2-based samples have lower electro-corrosion rates than Mg. Their Vickers hardness is 6.8-10.2GPa, and these values are higher than those of biodegradable Mg-based alloys. MgB2 has low in vitro biocompatibility, good antibacterial activity against Escherichia coli, and mild activity against Staphylococcus aureus. Our results suggest that MgB2-based materials deserve attention in biomedical applications, such as implants or sterile medical instruments. Copyright © 2014 Elsevier B.V. All rights reserved.

The CHT2 Project: Diachronic 3d Reconstruction of Historic Sites

NASA Astrophysics Data System (ADS)

Guidi, G.; Micoli, L.; Gonizzi Barsanti, S.; Malik, U.

2017-08-01

Digital modelling archaeological and architectural monuments in their current state and in their presumed past aspect has been recognized not only as a way for explaining to the public the genesis of a historical site, but also as an effective tool for research. The search for historical sources, their proper analysis and interdisciplinary relationship between technological disciplines and the humanities are fundamental for obtaining reliable hypothetical reconstructions. This paper presents an experimental activity defined by the project Cultural Heritage Through Time - CHT2 (http://cht2-project.eu), funded in the framework of the Joint Programming Initiative on Cultural Heritage (JPI-CH) of the European Commission. Its goal is to develop time-varying 3D products, from landscape to architectural scale, deals with the implementation of the methodology on one of the case studies: the late Roman circus of Milan, built in the era when the city was the capital of the Western Roman Empire (286-402 A.D). The work presented here covers one of the cases in which the physical evidences have now been almost entirely disappeared. The diachronic reconstruction is based on a proper mix of quantitative data originated by 3D surveys at present time, and historical sources like ancient maps, drawings, archaeological reports, archaeological restrictions decrees and old photographs. Such heterogeneous sources have been first georeferenced and then properly integrated according to the methodology defined in the framework of the CHT2 project, to hypothesize a reliable reconstruction of the area in different historical periods.

Modification of the vertically generalized production model for the turbid waters of Ariake Bay, southwestern Japan

NASA Astrophysics Data System (ADS)

Tripathy, S. C.; Ishizaka, J.; Siswanto, E.; Shibata, T.; Mino, Y.

2012-01-01

The vertically generalized production model (VGPM), which was designed for open ocean waters ( Behrenfeld and Falkowski, 1997a; henceforth BF), was evaluated using in situ measurements of primary productivity (PP) in the characteristically turbid coastal waters of Ariake Bay, southwestern Japan, to develop a regionally modified version of the model. The euphotic depth ( Z eu)-integrated PP (IPP) calculated from the VGPM using in situ chlorophyll a (Chl a) and sea surface temperature (SST) was significantly overestimated (by factors of 2-3), but 52% of the observed variability was explained. The weak correlation could have partially resulted from overestimations by the sub-models embedded in the original VGPM model for estimation of Z eu ( Morel and Berthon, 1989; henceforth MB) and the optimal Chl a-normalized PP ( poptB). The sub-model estimates of poptB and Z eu with in situpoptB and Z eu showed significant improvement, accounting for 84% of the variability and causing less overestimation. Z eu was the most important parameter influencing the modeled IPP variation in Ariake Bay. Previous research suggested that the Z eu model, which was based on surface Chl a, overestimated in situ Z eu by a factor of 2-3, resulting in weak correlation between the modeled and in situ IPP. The Z eu sub-model was not accurate in the present study area because it was basically developed for clear (case 1) waters. A better estimation of Z eu could be obtained from the in situ remote sensing reflectance ( R rs) using a quasi-analytical algorithm (QAA) in this turbid water ecosystem. Among the parameters of PP models, poptB is conventionally considered the most important. However, in this study poptB was of secondary importance because the contribution of poptB to the variation in modeled IPP was less than the contribution of Z eu. The modeled and in situpoptB were weakly correlated with 50% of the data points that overestimated the in situ values. The estimation of Chl a was improved by optimizing the Chl a algorithm with in situ R rs data. Incorporating the QAA-based Z eu and the optimized Chl a and constant (median) poptB value led to improved performance of the VGPM for the study area. Thus, even though the VGPM is a global open ocean model, when coupled with turbid water algorithms for Z eu and Chl a and constant (median) poptB, it provided realistic estimates of IPP in the turbid water ecosystem of Ariake Bay.

Comparing pharmaceutical pricing and reimbursement policies in Croatia to the European Union Member States

PubMed Central

Vogler, Sabine; Habl, Claudia; Bogut, Martina; Vončina, Luka

2011-01-01

Aim To perform a comparative analysis of the pharmaceutical pricing and reimbursement systems in Croatia and the 27 European Union (EU) Member States. Methods Knowledge about the pharmaceutical systems in Croatia and the 27 EU Member States was acquired by literature review and primary research with stakeholders. Results Pharmaceutical prices are controlled at all levels in Croatia, which is also the case in 21 EU Member States. Like many EU countries, Croatia also applies external price referencing, ie, compares prices with other countries. While the wholesale remuneration by a statutorily regulated linear mark-up is applied in Croatia and in several EU countries, the pharmacy compensation for dispensing reimbursable medicines in the form of a flat rate service fee in Croatia is rare among EU countries, which usually apply a linear or regressive pharmacy mark-up scheme. Like in most EU countries, the Croatian Social Insurance reimburses specific medicines at 100%, whereas patients are charged co-payments for other reimbursable medicines. Criteria for reimbursement include the medicine’s importance from the public health perspective, its therapeutic value, and relative effectiveness. In Croatia and in many EU Member States, reimbursement is based on a reference price system. Conclusion The Croatian pharmaceutical system is similar to those in the EU Member States. Key policies, like external price referencing and reference price systems, which have increasingly been introduced in EU countries are also applied in Croatia and serve the same purpose: to ensure access to medicines while containing public pharmaceutical expenditure. PMID:21495202

Eu(2+)-Activated Alkaline-Earth Halophosphates, M5(PO4)3X:Eu(2+) (M = Ca, Sr, Ba; X = F, Cl, Br) for NUV-LEDs: Site-Selective Crystal Field Effect.

PubMed

Kim, Donghyeon; Kim, Sung-Chul; Bae, Jong-Seong; Kim, Sungyun; Kim, Seung-Joo; Park, Jung-Chul

2016-09-06

Eu(2+)-activated M5(PO4)3X (M = Ca, Sr, Ba; X = F, Cl, Br) compounds providing different alkaline-earth metal and halide ions were successfully synthesized and characterized. The emission peak maxima of the M5(PO4)3Cl:Eu(2+) (M = Ca, Sr, Ba) compounds were blue-shifted from Ca to Ba (454 nm for Ca, 444 nm for Sr, and 434 nm for Ba), and those of the Sr5(PO4)3X:Eu(2+) (X = F, Cl, Br) compounds were red-shifted along the series of halides, F → Cl → Br (437 nm for F, 444 nm for Cl, and 448 nm for Br). The site selectivity and occupancy of the activator ions (Eu(2+)) in the M5(PO4)3X:Eu(2+) (M = Ca, Sr, Ba; X = F, Cl, Br) crystal lattices were estimated based on theoretical calculation of the 5d → 4f transition energies of Eu(2+) using LCAO. In combination with the photoluminescence measurements and theoretical calculation, it was elucidated that the Eu(2+) ions preferably enter the fully oxygen-coordinated sites in the M5(PO4)3X:Eu(2+) (M = Ca, Sr, Ba; X = F, Cl, Br) compounds. This trend can be well explained by "Pauling's rules". These compounds may provide a platform for modeling a new phosphor and application in the solid-state lighting field.

Introducing Eu{sup 2+} into yellow phosphor LiBaB{sub 9}O{sub 15}:Ce{sup 3+}, Dy{sup 3+} as blue emitting source to realize white emission

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Ting; Li, Panlai, E-mail: li_panlai@126.com; Fu, Nian, E-mail: funian3678@163.com

A series of Dy{sup 3+}, Ce{sup 3+}/Dy{sup 3+}, Eu{sup 2+}/Dy{sup 3+} and Ce{sup 3+}/Eu{sup 2+}/Dy{sup 3+} doping LiBaB{sub 9}O{sub 15} (LBB) phosphors were synthesized via a high temperature solid-state method. LBB:Dy{sup 3+} cannot create light under ultraviolet radiation, however, LBB:Ce{sup 3+}, Dy{sup 3+} can produce yellow emission under 295 nm excitation. The energy transfer occurs from Ce{sup 3+} to Dy{sup 3+} ions via electric dipole-dipole interaction and the critical distance is estimated to be 21.15 Å based on concentration quenching model. Generally, Eu{sup 2+} ion is a sensitizer to Dy{sup 3+} ion, however, there is only the emission of Eu{supmore » 2+} in LBB:Eu{sup 2+}, Dy{sup 3+}, which means there is no energy transfer from Eu{sup 2+} to Dy{sup 3+} ions. Interestingly enough, when doping Eu{sup 2+} ion into LBB:Ce{sup 3+}, Dy{sup 3+}, white emission can be achieved by increase the blue (350–425 nm) emission intensity. The spectral property, quantum efficiency, CIE chromaticity coordinates and thermal quenching property of LBB:Ce{sup 3+}, Eu{sup 2+}, Dy{sup 3+} are investigated. The results indicate that LBB:Ce{sup 3+}, Eu{sup 2+}, Dy{sup 3+} may be a potential application to white light emitting diodes. - Graphical abstract: LBB:Ce{sup 3+}, Dy{sup 3+} can create white emission by doping Eu{sup 2+} ions. - Highlights: • LBB:Ce{sup 3+}, Dy{sup 3+} can produce white emission by doping Eu{sup 2+} ion. • There is no energy transfer from Eu{sup 2+} to Dy{sup 3+} ions. • Energy transfer occurs from Ce{sup 3+} to Dy{sup 3+} ions. • LBB:Ce{sup 3+}, Eu{sup 2+}, Dy{sup 3+} may be a potential application for white LEDs.« less

Novel tunable green-red-emitting oxynitride phosphors co-activated with Ce3+, Tb3+, and Eu3+: photoluminescence and energy transfer.

PubMed

Huo, Jiansheng; Dong, Langping; Lü, Wei; Shao, Baiqi; You, Hongpeng

2017-07-14

A series of novel Ce 3+ , Tb 3+ and Eu 3+ ion doped Y 4 SiAlO 8 N-based oxynitride phosphors were synthesized by the solid-state method and characterized by X-ray powder diffraction, scanning electron microscopy, photoluminescence, lifetimes and thermo-luminescence. The excitation of the Ce 3+ /Tb 3+ co-doped and Ce 3+ /Tb 3+ /Eu 3+ tri-doped phosphor with near-UV radiation results in strong linear Tb 3+ green and Eu 3+ red emission. The occurrence of Ce 3+ -Tb 3+ and Ce 3+ -Tb 3+ -Eu 3+ energy transfer processes is responsible for the bright green or red luminescence. The Tb 3+ ion acting as an energy transfer bridge can alleviate MMCT quenching between the Ce 3+ -Eu 3+ ion pairs. The lifetime measurements demonstrated that the energy-transfer mechanisms of Ce 3+ → Tb 3+ and Tb 3+ → Eu 3+ are dipole-quadrupole and quadrupole-quadrupole interactions, respectively. The temperature dependent luminescence measurements showed that as-prepared green/red phosphors have good thermal stability against temperature quenching. The obtained results indicate that these phosphors might serve as promising candidates for n-UV LEDs.

Synthesis of novel Eu(III) luminescent probe based on 9- acridinecarboxylic acid skelton for sensing of ds-DNA.

PubMed

Azab, Hassan A; Hussein, Belal H M; El-Falouji, Abdullah I

2012-03-01

Eu(III)-9-acridinecarboxylate (9-ACA) complex was synthesized and characterized by elemental analysis, conductivity measurement, IR spectroscopy, thermal analysis, mass spectroscopy, (1)H-NMR, fluorescence and ultraviolet spectra. The results indicated that the composition of this complex is [Eu(III)-(9-ACA)(2)(NCS)(C(2)H(5)OH)(2)] 2.5 H(2)O and the oxygen of the carbonyl group coordinated to Eu(III). The interaction between the complex with nucleotides guanosine 5'- monophosphate (5'-GMP), adenosine 5'-diphosphates (5'-ADP), inosine (5'-IMP) and CT-DNA was studied by fluorescence spectroscopy. The fluorescence intensity of Eu(III)-9-acridinecarboxylate complex was enhanced with the addition of CT-DNA. The effect of pH values on the fluorescence intensity of Eu(III) complex was investigated. Under experimental conditions, the linear range was 9-50 ng mL(-1) for calf thymus DNA (CT- DNA) and the corresponding detection limit was 5 ng mL(-1). The results showed that Eu(III)-(9-ACA)(2) complex binds to CT-DNA with stability constant of 2.41 × 10(4) M.

Preparation and characterization of new photoluminescent nano-powder based on Eu3+:La2Ti2O7 and dispersed into silica matrix for latent fingerprint detection

NASA Astrophysics Data System (ADS)

Saif, M.; Alsayed, N.; Mbarek, A.; El-Kemary, M.; Abdel-Mottaleb, M. S. A.

2016-12-01

Pure lanthanum titanate doped with europium metal ions (La2Ti2O7:Eu3+) and dispersed in silica matrix phosphor powder was prepared by sol-gel process followed by thermal treatment. The prepared nanophosphors were characterized by powder X-ray Diffraction (XRD), Fourier Transform Infrared (FT-IR), Transmission Electron Microscope (TEM), Energy Dispersive Spectroscopy (EDX), and Photoluminescence Spectroscopy (PL). The effects of silica, thermal treatment, Eu3+ ion, and surfactant (CTAB) concentrations on the crystal, morphology, and photoluminescence properties were investigated. The present work found that dispersion of La2Ti2O7:Eu3+ into silica matrix significantly altered the morphology of La2Ti2O7:Eu3+ from high crystalline micro-plate like shape into amorphous aggregated Nano-spherical shape. The high separated spherical shape with intense red PL emission and long lifetime was obtained from 10 mol% Eu3+:La2Ti2O7:Eu3+, dispersed into silica matrix, and prepared in the presence of CTAB. The high PL Nano-phosphor has been successfully used in developing latent fingerprint from various forensic relevant materials.

Concentration-independent pH detection with a luminescent dimetallic Eu(III)-based probe.

PubMed

Moore, Jeremiah D; Lord, Richard L; Cisneros, G Andrés; Allen, Matthew J

2012-10-24

A pH-responsive, luminescent, dimetallic Eu(III)-containing complex has been synthesized and exhibits a unique mechanism of response. The luminescence-decay rate of the complex is slow, due to a lack of water molecules coordinated to the Eu(III) ions. However, the luminescence-decay rate decreases with increasing pH over a biologically relevant range of 4-8. Physical characterization and computational analysis suggest that the pH response is due to protonation of a bridging alkoxide at lower pH values. Modulation of the luminescence-decay rate is independent from the concentration of Eu(III), which we expect to be useful in the non-invasive imaging of in vivo pH.

Luminescence of BaBrI and SrBrI single crystals doped with Eu2+

NASA Astrophysics Data System (ADS)

Shalaev, A. A.; Shendrik, R.; Myasnikova, A. S.; Bogdanov, A.; Rusakov, A.; Vasilkovskyi, A.

2018-05-01

The crystal growth procedure and luminescence properties of pure and Eu2+-doped BaBrI and SrBrI crystals are reported. Emission and excitation spectra were recorded under ultraviolet and vacuum ultraviolet excitations. The energy of the first Eu2+ 4f-5d transition and SrBrI band gap are obtained. The electronic structure calculations were performed within GW approximation as implemented in the Vienna Ab Initio Simulation Package. The energy between lowest Eu2+ 5d state and the bottom of conduction band are found based on luminescence quenching parameters. The vacuum referred binding energy diagram of lanthanide levels was constructed using the chemical shift model.

Luminescent single-walled carbon nanotube-sensitized europium nanoprobes for cellular imaging

PubMed Central

Avti, Pramod K; Sitharaman, Balaji

2012-01-01

Lanthanoid-based optical probes with excitation wavelengths in the ultra-violet (UV) range (300–325 nm) have been widely developed as imaging probes. Efficient cellular imaging requires that lanthanoid optical probes be excited at visible wavelengths, to avoid UV damage to cells. The efficacy of europium-catalyzed single-walled carbon nanotubes (Eu-SWCNTs), as visible nanoprobes for cellular imaging, is reported in this study. Confocal fluorescence microscopy images of breast cancer cells (SK-BR-3 and MCF-7) and normal cells (NIH 3T3), treated with Eu-SWCNT at 0.2 μg/mL concentration, showed bright red luminescence after excitation at 365 nm and 458 nm wavelengths. Cell viability analysis showed no cytotoxic effects after the incubation of cells with Eu-SWCNTs at this concentration. Eu-SWCNT uptake is via the endocytosis mechanism. Labeling efficiency, defined as the percentage of incubated cells that uptake Eu-SWCNT, was 95%–100% for all cell types. The average cellular uptake concentration was 6.68 ng Eu per cell. Intracellular localization was further corroborated by transmission electron microscopy and Raman microscopy. The results indicate that Eu-SWCNT shows potential as a novel cellular imaging probe, wherein SWCNT sensitizes Eu3+ ions to allow excitation at visible wavelengths, and stable time-resolved red emission. The ability to functionalize biomolecules on the exterior surface of Eu-SWCNT makes it an excellent candidate for targeted cellular imaging. PMID:22619533

Eu3 + amidst ionic copper in glass: Enhancement through energy transfer from Cu+, or quenching by Cu2 +?

NASA Astrophysics Data System (ADS)

Jiménez, José A.

2017-02-01

A barium-phosphate glass system doped with europium(III) and containing a high concentration of copper(I) together with a copper(II) remnant has been studied spectroscopically. The main object is to elucidate whether the orange-red emission of Eu3 + ions succeeds through sensitization via luminescent Cu+ ions or else is preferentially quenched by non-radiative transfer to Cu2 +. A characterization of the melt-quenched glass was first performed by UV/Vis optical absorption, 31P nuclear magnetic resonance and infrared absorption spectroscopy. A photoluminescence (PL) spectroscopy and emission decay dynamics assessment was subsequently performed. Despite the concentration of Cu+ being estimated to be much higher than that of Cu2 +, the data shows that quenching of Eu3 + PL by Cu2 + dominates. The lifetime analysis of emitting centers Cu+ and Eu3 + points to the origin of the manifestation being that the Eu3 + → Cu2 + non-radiative transfer rate responsible for the quenching is almost two times higher than that for the Cu+ → Eu3 + transfer accountable for the enhancement. Finally, an effort was made for the determination of Cu2 + in the glass containing Cu+, Cu2 + and Eu3 + ions based on the Eu3 + (5D0) emission decay rates. It was found to be in excellent agreement with the UV/Vis spectrophotometric approach, thus supporting the utility of Eu3 + ions for optical sensing of copper(II) in the solid state.

Determination of natural line widths of Kα X-ray lines for some elements in the atomic range 50≤Z≤65 at 59.5 keV

NASA Astrophysics Data System (ADS)

Kündeyi, Kadriye; Aylıkcı, Nuray Küp; Tıraşoǧlu, Engin; Kahoul, Abdelhalim; Aylıkcı, Volkan

2017-02-01

The semi-empirical determination of natural widths of Kα X-ray lines (Kα1 and Kα2) were performed for Sn, Sb, Te, I, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd and Tb. For the semi-empirical determination of the line widths, K shell fluorescence yields of elements were measured. The samples were excited by 59.5 keV γ rays from a 241Am annular radioactive source in order to measure the K shell fluorescence yields. The emitted K X-rays from the samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. The measured K shell fluorescence yields were used for the calculation of K shell level widths. Finally, the natural widths of K X-ray lines were determined as the sums of levels which involved in the transition. The obtained values were compared with earlier studies.

Factors influencing the transferability of occupational safety and health economic incentive schemes between different countries.

PubMed

Elsler, Dietmar; Eeckelaert, Lieven

2010-06-01

This article looks at the factors that influence the transferability of different types of occupational safety and health (OSH) economic incentives from one country to another. To review the legal, political, and cultural framework conditions for economic incentive schemes in the European Union (EU), the European Agency for Safety and Health at Work (EU-OSHA) surveyed EU member states about the state of such schemes in their countries. In addition to the survey responses, relevant information on existing schemes and their national context within the 27 EU member states was gathered through reports, articles, and databases. Following this, countries were clustered according to cross-cultural differences. Despite the apparent variations in Europe's social security systems, there is a high degree of similarity between the countries regarding the basic criteria of design of the system. In addition, different kinds of incentives are used in different member states regardless of the social insurance system. When it comes to insurance incentive schemes, the fundamental difference between countries is whether the workers' compensation scheme is based on a competitive market between private insurance companies or a kind of monopoly structure, where the employers do not have the choice between several insurance companies. A clear majority of 19 of the 27 EU member states have a monopoly system. Subsidy systems, tax incentives, and insurance-based "experience rating" are theoretically -possible in all EU countries. In competitive insurance markets, effort-based incentives are more difficult to achieve. A possible solution could be the introduction of long-term contracts or the creation of a common prevention fund, financed equally by all insurers.

European Union centralised procedure for marketing authorisation of oncology drugs: an in-depth review of its efficiency.

PubMed

Netzer, Tilo

2006-03-01

In the European Union (EU) 20 anticancer agents have been successfully authorised via the Centralised Procedure since its implementation in 1995. Public information on these 20 agents has been reviewed in order to evaluate the effectiveness of the available regulatory mechanisms to facilitate the marketing authorisation of such drugs in the EU. These mechanisms include orphan drug legislation, exceptional circumstances provision and the accelerated evaluation procedure. Based on the fact that the EU orphan drug legislation was not implemented before the year 2000 no conclusions on its effectiveness to facilitate oncology drug development can be drawn today. Much more data are available on the effects of the exceptional circumstances provision, which was used in 6 out of 10 cases over the past four years. An analysis of the clinical data packages indicates that this provision allows authorisation of innovative oncology drugs based on smaller clinical data sets than required for full approval. The accelerated evaluation procedure was used in only one case and significantly reduced the scientific review time at the EU agencies. However, this mechanism does not influence the administrative time at the authorities, which accounted for almost one-third of the overall duration of the EU marketing authorisation procedures for oncology drugs. Revision of the EU drug legislation brings about some changes to the above-described provisions, with the potential for an improvement in the current situation. Thus, its implementation offers the chance to reduce the time that innovative oncology agents take to reach the market, although -- based on experience with the current procedures -- more effort is likely to be required to achieve this goal.

Solvent-induced assembly of two helical Eu(III) metal-organic frameworks and fluorescence sensing activities towards nitrobenzene and Cu2+ ions

NASA Astrophysics Data System (ADS)

Ma, Ranran; Chen, Zhiwei; Wang, Suna; Yao, Qingxia; Li, Yunwu; Lu, Jing; Li, Dacheng; Dou, Jianmin

2017-08-01

Two helical Eu(III) metal-organic frameworks, namely, {[Eu(L)(DMF)(H2O)]·0.5DMF}n (1) and [Eu(L)(DEF)(H2O)]n (2) (H3L=3,5-bis(2-carboxylphenoxy)benzoic acid, DMF=N,N-dimethylformamide, DEF=N,N-diethylformamide), have been solvothermally synthesized in different solvents, respectively. Both complexes possess helical structures through the connectivity of Eu atoms and phenolic-oxygen containing branches of the flexible multicarboxylate ligand. Based on different helices, these two complexes exhibited hexagonal and tetragonal channels, respectively. Both complexes possess (3,6)-connected (4.62)2(42.610.83) topology but with different long Schlafli symbol. The solvent plays an important role in the formation of the final frameworks. Both complexes can sensitively and selectively detect nitrobenzene and Cu2+ ions.

Improving cancer control in the European Union: conclusions from the Lisbon round-table under the Portuguese EU Presidency, 2007.

PubMed

Gouveia, Joaquim; Coleman, Michel P; Haward, Robert; Zanetti, Roberto; Hakama, Matti; Borras, Josep Maria; Primic-Zakelj, Maja; de Koning, Harry J; Travado, Luzia

2008-07-01

Cancer is a major cause of morbidity and mortality in the European Union (EU), and a public health burden. Improving cancer control in the EU will require implementation of efficient strategies within Member States and better policy coordination between them. In cooperation between the rotating EU Presidencies of Germany (2007), Portugal (2007) and Slovenia (2008), special attention was devoted to an integrated approach to cancer control in EU policies and programmes. A round-table focussed on national cancer plans, population-based cancer registries and cancer screening programmes was held during the Health Strategies in Europe meeting in Lisbon in July 2007, under the Portuguese Presidency. These three topics were selected as critical for improving cancer control at both national and European levels. The round-table was designed to produce a set of recommendations to inform EU cancer policy. This paper provides a résumé of the conclusions and recommendations, to stimulate wider discussion and policy development. The conclusions of the meeting were presented at the Employment, Social Policy, Health and Consumer Affairs Council in December 2007 and cancer was included in the Council Conclusions for the new European Health Strategy. Success in cancer control will require consistent attention from future EU Presidencies, such as the initiative of the Slovenian EU Presidency in early 2008.

Structure and physical properties of EuTa{sub 2}O{sub 6} tungsten bronze polymorph

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kolodiazhnyi, T., E-mail: kolodiazhnyi.taras@nims.go.jp; Sakurai, H.; Vasylkiv, O.

A tetragonal tungsten bronze (TTB) polymorph of EuTa{sub 2}O{sub 6} was prepared and analyzed. EuTa{sub 2}O{sub 6} crystallizes in the centrosymmetric Pnam space group (with unit cell: a = 12.3693, b = 12.4254, and c = 7.7228 Å) isomorphous with orthorhombic β-SrTa{sub 2}O{sub 6}. In contrast to early reports, we see no evidence of deviation from paramagnetic Curie-Weiss behavior among the Eu{sup 2+} 4f{sup 7}spins in EuTa{sub 2}O{sub 6} down to 2 K. Dielectric constant shows a broad peak at ca. 50 K with dielectric dispersion resembling diffuse phase transition. The relaxation time, however, follows a simple (non-freezing) thermally activated process with an activation energy of 92 meV and anmore » attempt frequency of f{sub 0} = 5.79 × 10{sup 12 }Hz. A thermal conductivity of EuTa{sub 2}O{sub 6} shows a low-temperature (T ≈ 30 K) “plateau” region reminiscent of a glass-like behaviour in Nb-based TTB compounds. This behaviour can be attributed to the loosely bound Eu{sup 2+} ions occupying large tricapped trigonal prismatic sites in the EuTa{sub 2}O{sub 6} structure.« less

The formation, structure and physical properties of M(2)Pd(14+x)B(5-y) compounds, with M =  La, Ce, Pr, Nd, Sm, Eu, Gd, Lu and Th.

PubMed

Royanian, E; Bauer, E; Kaldarar, H; Galatanu, A; Khan, R T; Hilscher, G; Michor, H; Reissner, M; Rogl, P; Sologub, O; Giester, G; Gonçalves, A P

2009-07-29

Novel ternary compounds, M(2)Pd(14+x)B(5-y) (M =  La, Ce, Pr, Nd, Sm, Eu, Gd, Lu, Th; x∼0.9, y∼0.1), have been synthesized by arc melting. The crystal structures of Nd(2)Pd(14+x)B(5-y) and Th(2)Pd(14+x)B(5-y) were determined from x-ray single-crystal data and both are closely related to the structure type of Sc(4)Ni(29)B(10). All compounds were characterized by Rietveld analyses and found to be isotypic with the Nd(2)Pd(14+x)B(5-y) type. Measurements of the temperature dependent susceptibility and specific heat as well as the temperature and field dependent resistivity were employed to derive basic information on bulk properties of these compounds. The electrical resistivity of M(2)Pd(14+x)B(5-y), in general, is characterized by small RRR (residual resistance ratio) values originating from defects inherent to the crystal structure. Whereas the compounds based on Ce, Nd, Sm and Gd exhibit magnetic order, those based on Pr and Eu seem to be non-magnetic, at least down to 400 mK. While the non-magnetic ground state of the Pr based compound is a consequence of crystalline electric field effects in the context of the non-Kramers ion Pr, the lack of magnetic order in the case of the Eu based compound results from an intermediate valence state of the Eu ion.

New GMO regulations for old: Determining a new future for EU crop biotechnology.

PubMed

Davison, John; Ammann, Klaus

2017-01-02

In this review, current EU GMO regulations are subjected to a point-by point analysis to determine their suitability for agriculture in modern Europe. Our analysis concerns present GMO regulations as well as suggestions for possible new regulations for genome editing and New Breeding Techniques (for which no regulations presently exist). Firstly, the present GMO regulations stem from the early days of recombinant DNA and are not adapted to current scientific understanding on this subject. Scientific understanding of GMOs has changed and these regulations are now, not only unfit for their original purpose, but, the purpose itself is now no longer scientifically valid. Indeed, they defy scientific, economic, and even common, sense. A major EU regulatory preconception is that GM crops are basically different from their parent crops. Thus, the EU regulations are "process based" regulations that discriminate against GMOs simply because they are GMOs. However current scientific evidence shows a blending of classical crops and their GMO counterparts with no clear demarcation line between them. Canada has a "product based" approach and determines the safety of each new crop variety independently of the process used to obtain it. We advise that the EC re-writes it outdated regulations and moves toward such a product based approach.  Secondly, over the last few years new genomic editing techniques (sometimes called New Breeding Techniques) have evolved. These techniques are basically mutagenesis techniques that can generate genomic diversity and have vast potential for crop improvement. They are not GMO based techniques (any more than mutagenesis is a GMO technique), since in many cases no new DNA is introduced. Thus they cannot simply be lumped together with GMOs (as many anti-GMO NGOs would prefer). The EU currently has no regulations to cover these new techniques. In this review, we make suggestions as to how these new gene edited crops may be regulated. The EU is at a turning point where the wrong decision could destroy European agricultural competitively for decades to come.

Fluorescence properties of Eu3+ ions doped borate and fluoroborate glasses containing lithium, zinc and lead.

PubMed

Venkatramu, V; Babu, P; Jayasankar, C K

2006-02-01

The influence of glass composition on the fluorescence properties of Eu3+ ions doped borate and fluoroborate glasses modified with Li+, Zn2+ and Pb2+ cations have been investigated. The magnitude of splittings of 7F1 levels are analyzed using crystal-field (CF) analysis. The relative intensities of 5D0 --> 7F2 to 5D0 --> 7F1 transitions, crystal-field strength parameters and decay times of the 5D0 level have been determined and are found to be lower for Pb based glasses than those of Zn/Li based glasses. The lifetimes of 5D0 level are found to increase when borate glasses are modified with pure fluorides than with oxides and oxyfluorides. The fluorescence decay of 5D0 level fits perfect single exponential in the Eu3+:glass systems studied which indicates the absence of energy transfer between Eu3+ ions in these glasses.

Rationalising polymer selection for supersaturated film forming systems produced by an aerosol spray for the transdermal delivery of methylphenidate.

PubMed

Edwards, A; Qi, S; Liu, F; Brown, M B; McAuley, W J

2017-05-01

Film forming systems offer a number of advantages for topical and transdermal drug delivery, in particular enabling production of a supersaturated state which can greatly improve drug absorption and bioavailability. However the suitability of individual film forming polymers to stabilise the supersaturated state and optimise delivery of drugs is not well understood. This study reports the use of differential scanning calorimetry (DSC) to measure the solubility of methylphenidate both as the free base and as the hydrochloride salt in two polymethacrylate copolymers, Eudragit RS (EuRS) and Eudragit E (EuE) and relates this to the ability of films formed using these polymers to deliver methylphenidate across a model membrane. EuRS provided greater methylphenidate delivery when the drug was formulated as the free base in comparison EuE because the lower solubility of the drug in EuRS provided a higher degree of drug saturation in the polymeric film. In contrast EuE provided greater delivery of methylphenidate hydrochloride as EuRS could not prevent its crystallisation from a supersaturated state. Methylphenidate flux across the membrane could be directly related to degree of saturation of the drug in the film formulation as estimated by the drug solubility in the individual polymers demonstrating the importance of drug solubility in the polymer included in film forming systems for topical/transdermal drug delivery. In addition DSC has been demonstrated to be a useful tool for determining the solubility of drugs in polymers used in film forming systems and the approaches outlined here are likely to be useful for predicting the suitability of polymers for particular drugs in film forming transdermal drug delivery systems. Copyright © 2017. Published by Elsevier B.V.

A qualitative case study of evaluation use in the context of a collaborative program evaluation strategy in Burkina Faso.

PubMed

D'Ostie-Racine, Léna; Dagenais, Christian; Ridde, Valéry

2016-05-26

Program evaluation is widely recognized in the international humanitarian sector as a means to make interventions and policies more evidence based, equitable, and accountable. Yet, little is known about the way humanitarian non-governmental organizations (NGOs) actually use evaluations. The current qualitative evaluation employed an instrumental case study design to examine evaluation use (EU) by a humanitarian NGO based in Burkina Faso. This organization developed an evaluation strategy in 2008 to document the implementation and effects of its maternal and child healthcare user fee exemption program. Program evaluations have been undertaken ever since, and the present study examined the discourses of evaluation partners in 2009 (n = 15) and 2011 (n = 17). Semi-structured individual interviews and one group interview were conducted to identify instances of EU over time. Alkin and Taut's (Stud Educ Eval 29:1-12, 2003) conceptualization of EU was used as the basis for thematic qualitative analyses of the different forms of EU identified by stakeholders of the exemption program in the two data collection periods. Results demonstrated that stakeholders began to understand and value the utility of program evaluations once they were exposed to evaluation findings and then progressively used evaluations over time. EU was manifested in a variety of ways, including instrumental and conceptual use of evaluation processes and findings, as well as the persuasive use of findings. Such EU supported planning, decision-making, program practices, evaluation capacity, and advocacy. The study sheds light on the many ways evaluations can be used by different actors in the humanitarian sector. Conceptualizations of EU are also critically discussed.

A Bonner Sphere Spectrometer based on a large 6LiI(Eu) scintillator: Calibration in reference monoenergetic fields

NASA Astrophysics Data System (ADS)

Bedogni, R.; Pola, A.; Costa, M.; Monti, V.; Thomas, D. J.

2018-07-01

A Bonner Sphere spectrometer employing a large, 11 mm diameter × 3 mm thickness, 6LiI(Eu) scintillator (LL-BSS), was assembled. The purpose was to produce a BSS similar in sensitivity to those based on 3He sensors, but using alternative sensors. With respect to the traditional BSS based on the 4 mm (diameter) × 4 mm (height) 6LiI(Eu), this new BSS is a factor of 3 more sensitive. LL-BSS response matrix, determined with MCNPX, was experimentally evaluated with monoenergetic reference neutron fields of 144 keV, 565 keV and 1.2 MeV available at NPL (Teddington, UK). The results of the experiment confirmed the correctness of the response matrix within an overall uncertainty lower than ±2%.

High-pressure x-ray diffraction study of YBO{sub 3}/Eu{sup 3+}, GdBO{sub 3}, and EuBO{sub 3}: Pressure-induced amorphization in GdBO{sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Pei; Xu, Chao; Ren, Xiangting

2014-01-28

Angle-dispersive synchrotron X-ray diffraction measurements were performed on vaterite-type YBO{sub 3}/Eu{sup 3+}, GdBO{sub 3}, and EuBO{sub 3}, respectively, up to 41 GPa at room temperature using a diamond-anvil cell. Pressure-induced amorphization was observed in hexagonal GdBO{sub 3} with a significant compression along the c-axis. Compared to the ions of the distorted GdBO{sub 3} phase, its anions may lose their long-range order prior to the cations at high pressures. Based on the experimental pressure-volume data, the obtained bulk moduli of YBO{sub 3}/Eu{sup 3+} and GdBO{sub 3} are 329 and 321 GPa, respectively, which are more than 90% larger than that of EuBO{sub 3}more » (167 GPa) and are presumably attributed to Gd{sup 3+} and Y{sup 3+} with a high density of d valence electrons.« less

One-pot carbonization synthesis of europium-doped carbon quantum dots for highly selective detection of tetracycline

NASA Astrophysics Data System (ADS)

Li Liu, Meng; Chen, Bin Bin; Yang, Tong; Wang, Jian; Liu, Xi Dong; Zhi Huang, Cheng

2017-03-01

The detection of tetracycline is of great significance because of its damaging effects on human health, such as renal toxicity and hemolytic anemia. Any release of tetracycline into the surrounding environment can produce bacterial drug resistance. We develop a new sensitive and selective detection approach for tetracycline in complex water samples by preparing europium-doped carbon quantum dots (Eu-CQDs) through a simple and rapid carbonization method operating at 200 °C for 5 min. The Eu-CQDs are characterized by blue photoluminescence, excitation-wavelength-dependent emission and excellent stability. Importantly, the fluorescence of the Eu-CQDs can be quenched efficiently by tetracycline, based on the strong inner filter effect mechanism between Eu-CQDs and tetracycline, making the fluorescence intensity ratio (I 0/I) of the Eu-CQDs at 465 nm correlate linearly with the concentration of tetracycline in the range of 0.5-200 μM, with a limit of detection of 0.3 μM. This shows the broad applicability of the Eu-CQDs in pursuing the concepts of simplicity and specificity for analytical purposes.

X-ray photoemission spectroscopy investigation of CaTiO{sub 3}:Eu for luminescence property: effect of Eu{sup 3+} ion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Kaichen; Zhao, Baijun; Gao, Lu, E-mail: gaolu@jlu.edu.cn

2016-06-15

Graphical abstract: The influence on the photoluminescent performance due to the electronic structure change in Eu-doped CaTiO{sub 3} of the specific core-level and valence band spectrum via X-ray photoemission spectroscopy were characterized. - Highlights: • Single phase CaTiO{sub 3} and CaTiO{sub 3}: Eu crystals were prepared under mild hydrothermal method. • Crystal structure, doping level and the relations to their luminescent property were discussed. • Charge compensation mechanism was discussed via valance band spectrum by XPS. - Abstract: Charge compensation of on-site Eu 4f–5d transition that determines the luminescent performance was confirmed with valance band spectrum. Influence of photoelectrons frommore » CaTiO{sub 3}: Eu to the corresponding luminescent performance was discussed based on the crystal structure, doping level and the relations to their luminescent property. This paper is important to further optimize the luminescent performance for improving the efficiency and reducing the cost in light emitting diode industry.« less

Fabrication and properties of Eu:Lu2O3 transparent ceramics for X-ray radiation detectors

NASA Astrophysics Data System (ADS)

Xie, Weifeng; Wang, Jing; Cao, Maoqing; Hu, Zewang; Feng, Yagang; Chen, Xiaopu; Jiang, Nan; Dai, Jiawei; Shi, Yun; Babin, Vladimir; Mihóková, Eva; Nikl, Martin; Li, Jiang

2018-06-01

Europium-doped lutetium oxide (Eu:Lu2O3) nano-powders were synthesized by a co-precipitation method from europium and lutetium nitrates using ammonium hydrogen carbonate (AHC) as the precipitant. Fine and low-agglomerated powders with average particle size of 68 nm were obtained by calcining the precursor at 1100 °C for 4 h. Using this powder as starting material, Eu:Lu2O3 transparent ceramics with the average grain size of ∼46 μm were fabricated by vacuum sintering at 1650 °C for 30 h, whose in-line transmittance reaches 66.3% at 611 nm. The influences of air annealing on optical transmittance, decay time, spectroscopic properties, light output and thermally stimulated luminescence of Eu:Lu2O3 ceramics were investigated in detail. Based on radioluminescence spectra, the light output of the annealed Eu:Lu2O3 ceramics is 10 times higher than that of the commercially available BGO single crystal, and it indicates that transparent Eu:Lu2O3 scintillation ceramics is a promising candidate for X-ray radiation detectors.

Synthesis and luminescence properties of Eu3+-doped KLa(MoO4)2 red-emitting phosphor

NASA Astrophysics Data System (ADS)

Zuo, Haoqiang; Liu, Yun; Li, Jinyang; Shi, Xiaolei; Gao, Weiping

2015-09-01

Eu3+-doped KLa(MoO4)2 phosphors were synthesized by a simple hydrothermal method. X-ray diffraction (XRD) analysis demonstrated that the as-prepared products were pure monoclinic phase of KLa(MoO4)2. Field emission scanning electron microscopy (FE-SEM) images indicated that the morphology of the prepared phosphors evolved from uniform spherical-like to irregular elliposid-like with increase of the concentration. The photoluminescence (PL) spectra displayed that the phosphors show strong red light around 618 nm, attributed to 5D0 → 7F2 transition of Eu3+ ion under 465 nm excitation, and the optimal Eu3+ doping concentration was about 15 mol.% based on the concentration dependent emission spectra. According to Dexter's theory the electric dipole-dipole interaction (D-D) is the main mechanism for energy transfer between Eu3+ and Eu3+ ions. The CIE chromaticity (x, y) of the phosphors were about (0.65, 0.35) and it is close to the standard red chromaticity of NTSC. Therefore, the phosphors could be used as red phosphors for white light-emitting diodes.

A novel double perovskite tellurate Eu3+-doped Sr2MgTeO6 red-emitting phosphor with high thermal stability

NASA Astrophysics Data System (ADS)

Liang, Jingyun; Zhao, Shancang; Yuan, Xuexia; Li, Zengmei

2018-05-01

A series of novel double perovskite tellurate red-emitting phosphors Sr2MgTeO6:xEu3+ (x = 0.05-0.40) were successfully synthesized by a high-temperature solid-state reaction method. The phase structure, photoluminescence properties and thermal stability of the phosphor were investigated in detail. The phosphor shows dominant emission peak at 614 nm belonging to the 5D0 → 7F2 electric dipole transition under 465 nm excitation. The luminescence intensity keeps increasing with increasing the content of Eu3+ to 25 mol%, and the critical transfer distance of Eu3+ was calculated to be 12 Å. The quenching temperature for Sr2MgTeO6:0.25Eu3+ was estimated to be above 500 K. This spectral feature reveals high color purity and excellent chromaticity coordinate characteristics. Therefore, Eu3+-doped Sr2MgTeO6 phosphors are potential red phosphors for blue chip-based white light-emitting diode and display devices.

Intermediate-valence state of the Sm and Eu in SmB 6 and EuCu 2 Si 2 : neutron spectroscopy data and analysis

DOE PAGES

Savchenkov, P. S.; Alekseev, P. A.; Podlesnyak, A.; ...

2018-01-11

For this study, magnetic neutron scattering data for Sm (SmB 6, Sm(Y)S) and Eu (EuCu 2Si 2- x Ge x ) intermediate-valence compounds have been analysed in terms of a generalized model of the intermediate-radius exciton. Special attention is paid to the correlation between the average ion's valence and parameters of the low-energy excitation in the neutron spectra, such as the resonance mode, including its magnetic form factor. Along with specific features of the formation of the intermediate-valence state for Sm and Eu ions, common physical mechanisms have been revealed for systems based on these elements from the middle ofmore » the rare-earth series. A consistent description of the existing experimental data has been obtained by using the concept of a loosely bound hole for the Eu f-electron shell in the intermediate-valence state, in analogy with the previously established loosely bound electron model for the Sm ion.« less

Intermediate-valence state of the Sm and Eu in SmB 6 and EuCu 2 Si 2 : neutron spectroscopy data and analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Savchenkov, P. S.; Alekseev, P. A.; Podlesnyak, A.

For this study, magnetic neutron scattering data for Sm (SmB 6, Sm(Y)S) and Eu (EuCu 2Si 2- x Ge x ) intermediate-valence compounds have been analysed in terms of a generalized model of the intermediate-radius exciton. Special attention is paid to the correlation between the average ion's valence and parameters of the low-energy excitation in the neutron spectra, such as the resonance mode, including its magnetic form factor. Along with specific features of the formation of the intermediate-valence state for Sm and Eu ions, common physical mechanisms have been revealed for systems based on these elements from the middle ofmore » the rare-earth series. A consistent description of the existing experimental data has been obtained by using the concept of a loosely bound hole for the Eu f-electron shell in the intermediate-valence state, in analogy with the previously established loosely bound electron model for the Sm ion.« less

The tension between cross-border cooperation in the European Area of Freedom, Security and Justice and the fundamental rights of mentally ill offenders in detention.

PubMed

Meysman, Michaël

2016-01-01

In two recent judgements, the European Court of Human Rights (ECtHR) has given an alarming signal regarding the placement, care and treatment of mentally disordered offenders in Belgium. This article analyses these judgements and the Court's assessment that Belgium faces a structural problem regarding the detention of people with a mental illness in prison. By exploring other recent ECtHR decisions across the EU and combining this with an analysis of international norms and standards, it contends that there is something amiss regarding the post-trial approach towards mentally disordered offenders in an EU-wide context. The potential hazards of this situation, from both an individual and an EU perspective are then presented by analysing the EU Framework Decision on the transfer of prisoners (which aims to facilitate offender rehabilitation) and the EU Court of Justice's interpretation of the relationship between instruments like the Framework Decision that are based on mutual recognition and fundamental rights. Lastly, the EU's initiative for enhancing procedural rights in criminal proceedings through the Roadmap trajectory, and the subsequent Commission Recommendation of 27 November 2013, are scrutinized. Based on this research, the article pinpoints the flaws and vacuums that currently exist for mentally disordered offenders, and the negative outcome this may have on the legitimacy and effectiveness of the European Area of Freedom, Security and Justice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Modelling forest carbon stock changes as affected by harvest and natural disturbances. II. EU-level analysis.

PubMed

Pilli, Roberto; Grassi, Giacomo; Kurz, Werner A; Moris, Jose V; Viñas, Raúl Abad

2016-12-01

Forests and the forest sector may play an important role in mitigating climate change. The Paris Agreement and the recent legislative proposal to include the land use sector in the EU 2030 climate targets reflect this expectation. However, greater confidence on estimates from national greenhouse gas inventories (GHGI) and more comprehensive analyses of mitigation options are needed to seize this mitigation potential. The aim of this paper is to provide a tool at EU level for verifying the EU GHGI and for simulating specific policy and forest management scenarios. Therefore, the Carbon Budget Model (CBM) was applied for an integrated assessment of the EU forest carbon (C) balance from 2000 to 2012, including: (i) estimates of the C stock and net CO 2 emissions for forest management (FM), afforestation/reforestation (AR) and deforestation (D), covering carbon in both the forest and the harvest wood product (HWP) pools; (ii) an overall analysis of the C dynamics associated with harvest and natural disturbances (mainly storms and fires); (iii) a comparison of our estimates with the data reported in the EU GHGI. Overall, the average annual FM sink (-365 Mt CO 2 year -1 ) estimated by the CBM in the period 2000-2012 corresponds to about 7 % of total GHG emissions at the EU level for the same period (excluding land use, land-use change and forestry). The HWP pool sink (-44 Mt CO 2 year -1 ) contributes an additional 1 %. Emissions from D (about 33 Mt CO 2 year -1 ) are more than compensated by the sink in AR (about 43 Mt CO 2 year -1 over the period). For FM, the estimates from the CBM were about 8 % lower than the EU GHGI, a value well within the typical uncertainty range of the EU forest sink estimates. For AR and D the match with the EU GHGI was nearly perfect (difference <±2 % in the period 2008-2012). Our analysis on harvest and natural disturbances shows that: (i) the impact of harvest is much greater than natural disturbances but, because of salvage logging (often very relevant), the impact of natural disturbances is often not easily distinguishable from the impact of harvest, and (ii) the impact of storms on the biomass C stock is 5-10 times greater than fires, but while storms cause only indirect emissions (i.e., a transfer of C from living biomass to dead organic matter), fires cause both direct and indirect emissions. This study presents the application of a consistent methodological approach, based on an inventory-based model, adapted to the forest management conditions of EU countries. The approach captures, with satisfactory detail, the C sink reported in the EU GHGI and the country-specific variability due to harvest, natural disturbances and land-use changes. To our knowledge, this is the most comprehensive study of its kind at EU level, i.e., including all the forest pools, HWP and natural disturbances, and a comparison with the EU GHGI. The results provide the basis for possible future policy-relevant applications of this model, e.g., as a tool to support GHGIs (e.g., on accounting for natural disturbances) and to verify the EU GHGI, and for the simulation of specific scenarios at EU level.

Flexible working hours, health, and well-being in Europe: some considerations from a SALTSA project.

PubMed

Costa, Giovanni; Akerstedt, Torbjorn; Nachreiner, Friedhelm; Baltieri, Federica; Carvalhais, José; Folkard, Simon; Dresen, Monique Frings; Gadbois, Charles; Gartner, Johannes; Sukalo, Hiltraud Grzech; Härmä, Mikko; Kandolin, Irja; Sartori, Samantha; Silvério, Jorge

2004-01-01

The project brought together researchers from 9 EU-Countries and resulted in a number of actions, in particular the following: (a) There is an urgent need of defining the concept of flexible working hours, since it has been used in many different and even counterintuitive ways; the most obvious distinction is where the influence over the working hours lies, that is between the "company-based flexibility" and the "individual-oriented flexibility"; (b) The review of the Legislation in force in the 15 European countries shows that the regulation of working times is quite extensive and covers (Council Directive 93/104/EC) almost all the various arrangements of working hours (i.e., part-time, overtime, shift, and night work), but fails to provide for flexibility; (c) According to the data of the Third EU Survey on Working Conditions, longer and "irregular" working hours are in general linked to lower levels of health and well-being; moreover, low (individual) flexibility and high variability of working hours (i.e., company-based flexibility) were consistently associated with poor health and well-being, while low variability combined with high autonomy showed positive effects; (d) Six substudies from different countries demonstrated that flexible working hours vary according to country, economic sector, social status, and gender; overtime is the most frequent form of company-based flexibility but has negative effects on stress, sleep, and social and mental health; individual flexibility alleviates the negative effects of the company-based flexibility on subjective health, safety, and social well-being; (e) The literature review was able to list more than 1,000 references, but it was striking that most of these documents were mainly argumentative with very little empirical data. Thus, one may conclude that there is a large-scale intervention ongoing in our society with almost completely unknown and uncontrolled effects. Consequently, there is a strong need for systematic research and well-controlled actions in order to examine in detail what flexible working hours are considered, what and where are their positive effects, in particular, as concerns autonomy, and what regulation seem most reasonable.

Reconstruction of Past Mediterranean Climate

NASA Astrophysics Data System (ADS)

García-Herrera, Ricardo; Luterbacher, Jürg; Lionello, Piero; Gonzáles-Rouco, Fidel; Ribera, Pedro; Rodó, Xavier; Kull, Christoph; Zerefos, Christos

2007-02-01

First MEDCLIVAR Workshop on Reconstruction of Past Mediterranean Climate; Pablo de Olavide University, Carmona, Spain, 8-11 November 2006; Mediterranean Climate Variability and Predictability (MEDCLIVAR; http://www.medclivar.eu) is a program that coordinates and promotes research on different aspects of Mediterranean climate. The main MEDCLIVAR goals include the reconstruction of past climate, describing patterns and mechanisms characterizing climate space-time variability, extremes at different time and space scales, coupled climate model/empirical reconstruction comparisons, seasonal forecasting, and the identification of the forcings responsible for the observed changes. The program has been endorsed by CLIVAR (Climate Variability and Predictability project) and is funded by the European Science Foundation.

Readout models for BaFBr0.85I0.15:Eu image plates

NASA Astrophysics Data System (ADS)

Stoeckl, M.; Solodov, A. A.

2018-06-01

The linearity of the photostimulated luminescence process makes repeated image-plate scanning a viable technique to extract a more dynamic range. In order to obtain a response estimate, two semi-empirical models for the readout fading of an image plate are introduced; they relate the depth distribution of activated photostimulated luminescence centers within an image plate to the recorded signal. Model parameters are estimated from image-plate scan series with BAS-MS image plates and the Typhoon FLA 7000 scanner for the hard x-ray image-plate diagnostic over a collection of experiments providing x-ray energy spectra whose approximate shape is a double exponential.

Remarkable changes in the photoluminescent properties of Y2Ce2O7:Eu(3+) red phosphors through modification of the cerium oxidation states and oxygen vacancy ordering.

PubMed

Raj, Athira K V; Prabhakar Rao, P; Sreena, T S; Sameera, S; James, Vineetha; Renju, U A

2014-11-21

A new series of red phosphors based on Eu(3+)-doped yttrium cerate [Y1.9Ce2O7:0.1Eu(3+), Y2Ce1.9O7:0.1Eu(3+) and Y2Ce2-xO7:xEu(3+) (x = 0.05, 0.10, 0.15, 0.20, 0.25 and 0.50)] was prepared via a conventional solid-state method. The influence of the substitution of Eu(3+) at the aliovalent site on the photoluminescent properties was determined by powder X-ray diffraction, FT Raman spectroscopy, X-ray photoelectron spectroscopy, transmission electron microscopy, scanning electron microscopy with energy-dispersive spectroscopy, UV-visible absorption spectroscopy, photoluminescence spectroscopy and lifetime measurements. The substitution of Eu(3+) at the Ce(4+) site induces a structural transition from a defect fluorite to a C-type structure, which increases the oxygen vacancy ordering and the distortion of the Eu(3+) environment, and decreases the formation of Ce(3+) states. In contrast, phosphors with isovalent substitution at the Y(3+) site exhibit the biphasic nature of defect fluorite and a C-type structure, thereby increasing the number of Ce(3+) oxidation states. These modifications resulted in remarkable changes in the photoluminescent properties of Y2Ce1.9O7:0.1Eu(3+) red phosphors, with emission intensities 3.8 times greater than those of the Ce0.9O2:0.1Eu(3+) and Y1.9Ce2O7:0.1Eu(3+). The photoluminescent properties of Y2Ce2-xO7:xEu(3+) were studied at different Eu(3+) concentrations under excitation with blue light. These phosphors emit intense red light due to the (5)D0-(7)F2 transition under excitation at 466 nm and no concentration quenching is observed with up to 50 mol% Eu(3+). They show increased lifetimes in the range 0.62-0.72 ms at Eu(3+) concentrations. The cation ordering linked to the oxygen vacancy ordering led to the uniform distribution of Eu(3+) ions in the lattice, thus allowing higher doping concentrations without quenching and consequently increasing the lifetime of the (5)D0 states. Our results demonstrate that significant improvements in the photoluminescence properties can be achieved by the structural alteration of a fluorite CeO2 to a C-type lattice.

Performance of europium-doped strontium iodide, transparent ceramics and bismuth-loaded polymer scintillators

NASA Astrophysics Data System (ADS)

Cherepy, N. J.; Payne, S. A.; Sturm, B. W.; O'Neal, S. P.; Seeley, Z. M.; Drury, O. B.; Haselhorst, L. K.; Rupert, B. L.; Sanner, R. D.; Thelin, P. A.; Fisher, S. E.; Hawrami, R.; Shah, K. S.; Burger, A.; Ramey, J. O.; Boatner, L. A.

2011-09-01

Recently discovered scintillators for gamma ray spectroscopy - single-crystal SrI2(Eu), GYGAG(Ce) transparent ceramic and Bismuth-loaded plastics - offer resolution and fabrication advantages compared to commercial scintillators, such as NaI(Tl) and standard PVT plastic. Energy resolution at 662 keV of 2.7% is obtained with SrI2(Eu), while 4.5% is obtained with GYGAG(Ce). A new transparent ceramic scintillator for radiographic imaging systems, GLO(Eu), offers high light yield of 70,000 Photons/MeV, high stopping, and low radiation damage. Implementation of single-crystal SrI2(Eu), Gd-based transparent ceramics, and Bi-loaded plastic scintillators can advance the state-of-the art in ionizing radiation detection systems.

Progress of the European Assistive Technology Information Network.

PubMed

Gower, Valerio; Andrich, Renzo

2015-01-01

The European Assistive Technology Information Network (EASTIN), launched in 2005 as the result of a collaborative EU project, provides information on Assistive Technology products and related material through the website www.eastin.eu. In the past few years several advancements have been implemented on the EASTIN website thanks to the contribution of EU funded projects, including a multilingual query processing component for supporting non expert users, a user rating and comment facility, and a detailed taxonomy for the description of ICT based assistive products. Recently, within the framework of the EU funded project Cloud4All, the EASTIN information system has also been federated with the Unified Listing of assistive products, one of the building blocks of the Global Public Inclusive Infrastructure initiative.

Performance of Europium-Doped Strontium Iodide, Transparent Ceramics and Bismuth-loaded Polymer Scintillators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cherepy, N J; Payne, S A; Sturm, B W

2011-08-30

Recently discovered scintillators for gamma ray spectroscopy, single crystal SrI{sub 2}(Eu), GYGAG(Ce) transparent ceramic and Bismuth-loaded plastics, offer resolution and fabrication advantages compared to commercial scintillators, such as NaI(Tl) and standard PVT plastic. Energy resolution at 662 keV of 2.7% is obtained with SrI{sub 2}(Eu), while 4.5% is obtained with GYGAG(Ce). A new transparent ceramic scintillator for radiographic imaging systems, GLO(Eu) offers high light yield of 70,000 Photons/MeV, high stopping, and low radiation damage. Implementation of single crystal SrI{sub 2}(Eu), Gd-based transparent ceramics, and Bi-loaded plastic scintillators can advance the state-of-the art in ionizing radiation detection systems.

Elastico-mechanoluminescence in CaZr(PO4)2:Eu2+ with multiple trap levels.

PubMed

Zhang, Jun-Cheng; Xu, Chao-Nan; Long, Yun-Ze

2013-06-03

We report on a novel elastico-mechanoluminescence (EML) phosphor of CaZr(PO4)2:Eu2+ for simultaneous luminescent sensing and imaging to mechanical load by the light-emitting of Eu2+ ions. The EML properties of CaZr(PO4)2:Eu2+ show an intense luminance (above 15 mcd m(-2)), a low load threshold (below 5 N), a broad measurement range for the dynamic load (up to 2000 N), and an accurate linear relationship of EML intensity against the applied load. The excellent EML characteristics are considered to originate from the piezoelectric crystal structure and the multiple trap levels with appropriate depths. An EML mechanism based on the electrons as the main charge carriers is proposed.

A microscopic solution to the magnetic detwinning mystery in EuFe2As2

NASA Astrophysics Data System (ADS)

Maiwald, J.; Mazin, I. I.; Nandi, S.; Xiao, Y.; Gegenwart, P.

One of the greatest recent advances in studying nematic phenomena in Fe-based superconductors was the mechanical detwinning of the 122-family compounds. Unfortunately, these techniques generate considerable stress in the investigated samples, which contaminates the results. Recently, we observed that a minuscule magnetic field of the order of 0.1 T irreversibly and persistently detwins EuFe2As2, opening an entirely new avenue for addressing nematicity. However, further development was hindered by the absence of a microscopic theory explaining this magnetic detwinning. In fact, Eu2+ has zero orbital moment and does not couple to the lattice, and its exchange coupling with the Fe sublattice cancels by symmetry. Moreover, further increase of the field to 1 T leads to a reorientation of Fe domains, while even larger fields 10 T reorient the domains once again. We will present a new microscopic model, based on a sizable biquadratic coupling between the Fe 3 d and Eu 4 f moments. This model quantitatively explains our old and new magnetization and neutron diffraction data, thus removing the veil of mystery and finally opening the door to full-scale research into magnetic detwinning and nematicity in Fe-based superconductors.

Using Eu(3+) as an atomic probe to investigate the local environment in LaPO4-GdPO4 monazite end-members.

PubMed

Huittinen, Nina; Arinicheva, Yulia; Schmidt, Moritz; Neumeier, Stefan; Stumpf, Thorsten

2016-12-01

In the present study, we have investigated the luminescent properties of Eu(3+) as a dopant in a series of synthetic lanthanide phosphates from the monazite group. Systematic trends in the spectroscopic properties of Eu(3+) depending on the size of the host cation and the dopant to ligand distance have been observed. Our results show that the increasing match between host and dopant radii when going from Eu(3+)-doped LaPO4 toward the smaller GdPO4 monazite decreases both the full width at half maximum of the Eu(3+) excitation peak, as well as the (7)F2/(7)F1 emission band intensity ratio. The decreasing Ln⋯O bond distance within the LnPO4 series causes a systematic bathochromic shift of the Eu(3+) excitation peak, showing a linear dependence of both the host cation size and the Ln⋯O distance. The linear relationship can be used to predict the energy band gap for Eu(3+)-doped monazites for which no Eu(3+) luminescent data is available. Finally, mechanisms for metal-metal energy transfer between host and dopant lanthanides have been explored based on recorded luminescence lifetime data. Luminescence lifetime data for Eu(3+) incorporated in the various monazite hosts clearly indicated that the energy band gap between the guest ion emission transition and the host ion absorption transition can be correlated to the degree of quenching observed in these materials with otherwise identical geometries and chemistries. Copyright © 2016 Elsevier Inc. All rights reserved.

Vaccination policies of immigrants in the EU/EEA Member States-the measles immunization example.

PubMed

Bica, Mihai A; Clemens, Ralf

2018-06-01

In 2015-16, the European Union/European Economic Area Member States (EU/EEA MSs) experienced an unprecedented volume and rate of migration, posing serious challenges to existing national immunization systems and strategies and raising the questions of where, when and who to vaccinate. We assessed existing strategies for vaccinating immigrant populations in the EU/EEA using measles as an example of the most important vaccine-preventable diseases. In this cross-sectional study, conducted from March to May 2016, an electronic questionnaire was sent to the Heads of National Immunization Technical Advisory Groups (NITAGs) or equivalent policy-making bodies in each of the 31 EU/EEA Member States. Responses were entered into a structured database and validated by survey responders for final analysis. Validated responses from all 31 EU/EEA NITAGs or equivalents showed that there is no common measles immunization policy for European immigrants. Policies vary widely from no policy at all (9 of 31, 29%) to vaccination of all comers (2 of 31, 6%), or vaccination of selected cohorts based on vaccination history (17 of 31, 55%) or serum antibody analysis (2 of 31, 6%). Further, the operational responsibilities for immigrant vaccination and documentation methods are not unified within the EU/EEA region. With some notable exceptions immunization policies to contain spread of infectious diseases through migration are either non-existent or vary widely between countries in the EU/EEA. With freedom of movement within the EU/EEA there ought to be harmonization and a common EU/EEA vaccination strategy to replace national policies for immigrant populations.

Disentangling the effects of climate variability and functional change on ecosystem carbon dynamics using semi-empirical modelling

NASA Astrophysics Data System (ADS)

Wu, J.; van der Linden, L.; Lasslop, G.; Carvalhais, N.; Pilegaard, K.; Beier, C.; Ibrom, A.

2012-04-01

The ecosystem carbon balance is affected by both external climatic forcing (e.g. solar radiation, air temperature and humidity) and internal dynamics in the ecosystem functional properties (e.g. canopy structure, leaf photosynthetic capacity and carbohydrate reserve). In order to understand to what extent and at which temporal scale, climatic variability and functional changes regulated the interannual variation (IAV) in the net ecosystem exchange of CO2 (NEE), data-driven analysis and semi-empirical modelling (Lasslop et al. 2010) were performed based on a 13 year NEE record in a temperate deciduous forest (Pilegaard et al 2011, Wu et al. 2012). We found that the sensitivity of carbon fluxes to climatic variability was significantly higher at shorter than at longer time scales and changed seasonally. This implied that the changing distribution of climate anomalies during the vegetation period could have stronger impacts on future ecosystem carbon balances than changes in average climate. At the annual time scale, approximately 80% of the interannual variability in NEE was attributed to the variation in the model parameters, indicating the observed IAV in the carbon dynamics at the investigated site was dominated by changes in ecosystem functioning. In general this study showed the need for understanding the mechanisms of ecosystem functional change. The method can be applied at other sites to explore ecosystem behavior across different plant functional types and climate gradients. Incorporating ecosystem functional change into process based models will reduce the uncertainties in long-term predictions of ecosystem carbon balances in global climate change projections. Acknowledgements. This work was supported by the EU FP7 project CARBO-Extreme, the DTU Climate Centre and the Danish national project ECOCLIM (Danish Council for Strategic Research).

Synthesis and Luminescence Properties of Novel Ce(3+)- and Eu(2+)-Doped Lanthanum Bromothiosilicate La3Br(SiS4)2 Phosphors for White LEDs.

PubMed

Lee, Szu-Ping; Liu, Shuang-De; Chan, Ting-Shan; Chen, Teng-Ming

2016-04-13

Novel Ce(3+)- and Eu(2+)-doped lanthanum bromothiosilicate La3Br(SiS4)2:Ce(3+)and La3Br(SiS4)2:Eu(2+) phosphors were prepared by solid-state reaction in an evacuated and sealed quartz glass ampule. The La3Br(SiS4)2:Ce(3+) phosphor generates a cyan emission upon excitation at 375 nm, whereas the La3Br(SiS4)2:Eu(2+) phosphor could be excited with extremely broad range from UV to blue region (300 to 600 nm) and generates a reddish-orange broadband emission centered at 640 nm. In addition, thermal luminescence properties of La3Br(SiS4)2:Ce(3+)and La3Br(SiS4)2:Eu(2+) phosphors from 20 to 200 °C were investigated. The combination of a 450 nm blue InGaN-based LED chip with the red-emitting La3Br(SiS4)2:Eu(2+) phosphor, and green-emitting BOSE:Eu(2+) commercial phosphor produced a warm-white light with the CRI value of ∼95 and the CCT of 5,120 K. Overall, these results show that the prepared phosphors may have potential applications in pc-WLED.

Quantitative risk assessment for the introduction of African swine fever virus into the European Union by legal import of live pigs.

PubMed

Mur, L; Martínez-López, B; Martínez-Avilés, M; Costard, S; Wieland, B; Pfeiffer, D U; Sánchez-Vizcaíno, J M

2012-04-01

The recent incursion and spread of African swine fever virus (ASFV) in the Russian Federation and Caucasus region, close to European Union (EU) borders, have increased the concerns regarding the probability of ASFV introduction into the EU. There are many potential routes of ASFV entry into EU, but here we specifically aimed to assess the probability of ASFV introduction by legal trade of pigs, which historically has been one of the most important ways of exotic diseases introduction into the EU. A stochastic model was used to estimate the monthly probability of ASFV introduction for each country of the EU. Results of this model suggest an annual probability for ASFV introduction in the whole EU by this way of 5.22*10(-3) , which approximately corresponds with one outbreak in 192years. The risk of ASFV introduction via live pigs was highest in Poland (69%), particularly during the months of November and December. As expected, Russian Federation is the country that most contributes to this risk, representing 68% of the overall annual risk. Methods and results presented here may be useful for informing risk-based surveillance and control programmes and, ultimately, for prevention and control of potential ASFV incursions into the EU. © 2011 Blackwell Verlag GmbH.

Novel EGCG assisted ultrasound synthesis of self-assembled Ca2SiO4:Eu(3+) hierarchical superstructures: Photometric characteristics and LED applications.

PubMed

Venkataravanappa, M; Nagabhushana, H; Darshan, G P; Daruka Prasad, B; Vijayakumar, G R; Premkumar, H B; Udayabhanu

2016-11-01

This paper reports for the first time ultrasound, EGCG assisted synthesis of pure and Eu(3+) (1-5mol%) activated Ca2SiO4 nanophosphors having self-assembled superstructures with high purity. The shape, size and morphology of the product were tuned by controlling influential parameters. It was found that morphology was highly dependent on EGCG concentration, sonication time, pH and sonication power. The probable formation mechanism for various hierarchical superstructures was proposed. The PL studies of Ca2SiO4:Eu(3+) phosphors can be effectively excited by the near ultraviolet (UV) (396nm) light and exhibited strong red emission around 613nm, which was attributed to the Eu(3+) ((5)D0→(7)F2) transition. The concentration quenching phenomenon was explained based on energy transfer between defect and Eu(3+) ions, electron-phonon coupling and Eu(3+)-Eu(3+) interaction. The Judd-Ofelt intensity parameters and radiative properties were estimated by using PL emission spectra. The photometric studies indicate that the obtained phosphors could be a promising red component for possible applications in the field of white light emitting diodes. Copyright © 2016 Elsevier B.V. All rights reserved.

The effect of titanite crystallisation on Eu and Ce anomalies in zircon and its implications for the assessment of porphyry Cu deposit fertility

NASA Astrophysics Data System (ADS)

Loader, Matthew A.; Wilkinson, Jamie J.; Armstrong, Robin N.

2017-08-01

The redox sensitivity of Ce and Eu anomalies in zircon has been clearly demonstrated by experimental studies, and these may represent an important tool in the exploration for porphyry Cu deposits which are thought to be derived from oxidised magmas. These deposits are significant because they are the source of much of the world's copper and almost all of the molybdenum and rhenium, key elements in many modern technologies. However, Ce and Eu anomalies in zircon are also affected by the co-crystallisation of REE bearing phases, such as titanite. Here, we report the trace element chemistry of zircons from titanite-bearing intrusions associated with mineralisation at the world class Oyu Tolgoi porphyry Cu-Au deposit (Mongolia). Based on these data, we suggest that neither zircon Eu/Eu*, nor Ce4+/Ce3+ are robust proxies for melt redox conditions, because they are both too strongly dependent on melt REE concentrations, which are usually poorly constrained and controlled by the crystallisation of titanite and other REE-bearing phases. In spite of this, Eu/Eu* can broadly distinguish between fertile and barren systems, so may still be an indicator of porphyry magma fertility, and a useful tool for exploration.

Crystal structure and luminescent properties of Sr2SiO4:Eu2+ phosphor prepared by sol-gel method.

PubMed

Pan, Heng; Li, Xu; Zhang, Jinping; Guan, Li; Su, Hongxin; Yang, Zhiping; Teng, Feng

2016-07-04

A series of Eu2+ (0.0025≤ × ≤0.025) activated Sr2SiO4:xEu2+ (SSO:xEu2+) phosphors were synthesized via a sol-gel method. The phosphors were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectroscopy. The differences between α' and β phase of SSO in the density of states and energy band gap were investigated. The energy gap of α'-SSO and β-SSO are 4.489 and 4.106 eV, respectively. While, two samples showed similar total and partial densities of states. Under the excitation by the ultra violet (UV) light (365 nm), the SSO:xEu2+ phosphor exhibited a green emission band from 400 to 700 nm, which was corresponding to the transition of 5d → 4f of Eu2+ ions. Two emission peaks at 464 and 532 nm could be obtained through Gauss fitting curves. The ratio of the blue to green emission peak decreased with the Eu2+ concentration and the peaks shifted regularly with it. The thermal quenching property was investigated and its activation energy was calculated. The results indicated that this phosphor could be a candidate of green phosphor for UV-based light-emitting diodes (LEDs).

Comparative Photoluminescence Properties and Judd-Ofelt Analysis of Eu3+ Ion-Activated Metal Molybdate Phosphors A2MoO6:Eu3+ (A = La, Y, Gd and Bi)

NASA Astrophysics Data System (ADS)

Han, Bing; Liu, Bingkun; Zhang, Jie; Li, Pengju; Shi, Hengzhen

2017-07-01

A class of red-emitting Eu3+ ion-activated metal molybdate A2MoO6:Eu3+ (A = La, Y, Gd and Bi) phosphors were synthesized by a conventional high-temperature solid-state reaction method. The x-ray diffraction patterns, scanning electron microscope images, Fourier transform infrared spectra, ultraviolet-visible diffuse reflection spectra as well as photoluminescence properties were measured to characterize the as-prepared samples. The photoluminescence properties including excitation/emission spectra, decay curves, Commission Internationale de L'Eclairage chromaticity coordinates and quantum efficiency were comparatively investigated in detail. The Judd-Ofelt theory was also applied to understand the radiative properties of f-f transitions of Eu3+ ions in this system for the first time. The as-prepared phosphors can be effectively excited with near-ultraviolet and/or blue light, and exhibit red emission belonging to the prevailing 5D0 → 7F2 transitions of Eu3+ with short decay time (millisecond level). The results demonstrated that A2MoO6:Eu3+ (A = La, Y, Gd and Bi) phosphors could have potential application as red-emitting phosphors in white light-emitting diodes based on near-ultraviolet and/or blue light-emitting diode chips.

Energy transfer driven tunable emission of Tb/Eu co-doped lanthanum molybdate nanophosphors

NASA Astrophysics Data System (ADS)

Thomas, Kukku; Alexander, Dinu; Sisira, S.; Gopi, Subash; Biju, P. R.; Unnikrishnan, N. V.; Joseph, Cyriac

2018-06-01

Tb3+/Eu3+ co-doped lanthanum molybdate nanophosphors were synthesized by conventional co-precipitation method. The Powder X-ray diffractogram revealed the formation of highly crystalline tetragonal nanocrystals with space group I41/a and the detailed analysis of the small variation of lattice parameters with Tb/Eu co-doping on the host lattice were carried out based on the ionic radii of the dopants. The FTIR spectra is employed to identify the fundamental vibrational modes in La2-x-y (MoO4)3:xTb, yEu nanocrystals. The formation of nanocrystals by oriented attachment was recognized from the HR TEM images and the d-spacing calculated was in accordance with that corresponding to highest intensity diffraction peak in the XRD patterns. The constituent elements present in the samples were identified with the aid of EDAX and elemental mapping analysis. The broad Mo6+- O2- CTB and the sharp excitation peaks of Tb and Eu identified from the UV-Vis absorption spectra facilitates the suitability of exciting the phosphors effectively over NUV and visible region of the spectra. The possibility of energy transfer from host to Tb3+/Eu3+ ions and from Tb3+ to Eu3+ ions were confirmed from the PL excitation spectra monitoring 5D0→7F2 transition of Eu3+ ions around 615 nm. The correlated analysis of PL emission spectra, life time measurements and CIE diagram, upon different excitation channels elucidate the excellent luminescent properties of La2-x-y (MoO4)3:xTb, yEu nanophosphors with tunable emission colours in a wide range varying from yellow green region to reddish orange region and the efficient energy transfer from Tb3+ to Eu3+ ions in lanthanum molybdate host lattice. The Tb→Eu energy transfer efficiency and probability were calculated from the decay measurements and the values were found to be satisfactory for exploiting the prepared nanophosphors for the development of multifunctional luminescent nanophosphors.

Irreversible phase transitions due to laser-based T-jump heating of precursor Eu:ZrO{sub 2}/Tb:Y{sub 2}O{sub 3} core/shell nanoparticles

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gunawidjaja, Ray; Diez-y-Riega, Helena; Eilers, Hergen, E-mail: eilers@wsu.edu

2015-09-15

Amorphous precursors of Eu-doped-ZrO{sub 2}/Tb-doped-Y{sub 2}O{sub 3} (p-Eu:ZrO{sub 2}/p-Tb:Y{sub 2}O{sub 3}) core/shell nanoparticles are rapidly heated to temperatures between 200 °C and 950 °C for periods between 2 s and 60 s using a CO{sub 2} laser. During this heating process the nanoparticles undergo irreversible phase changes. The fluorescence spectra due to Eu{sup 3+} dopants in the core and Tb{sup 3+} dopants in the shell are used to identify distinct phases within the material and to generate time/temperature phase diagrams. Such phase diagrams can potentially help to determine unknown time/temperature histories in thermosensor applications. - Graphical abstract: A CO{sub 2}more » laser is used for rapid heating of p-Eu:ZrO{sub 2}/p-Tb:Y{sub 2}O{sub 3} core/shell nanoparticles. Optical spectra are used to identify distinct phases and to determine its thermal history. - Highlights: • Synthesized oxide precursors of lanthanide doped core/shell nanoparticles. • Heated core/shell nanoparticles via laser-based T-jump technique. • Observed time- and temperature-dependent irreversible phase transition.« less

New transparent flexible nanopaper as ultraviolet filter based on red emissive Eu(III) nanofibrillated cellulose

NASA Astrophysics Data System (ADS)

Zhang, Zhao; Chang, Hui; Xue, Bailiang; Han, Qing; Lü, Xingqiang; Zhang, Sufeng; Li, Xinping; Zhu, Xunjin; Wong, Wai-kwok; Li, Kecheng

2017-11-01

A new kind of highly red emissive and transparent nanopapers as ultraviolet filter are produced from lanthanide complex Eu(TTA)3(H2O)2 grafted nanofibrillated cellulose (NFC) by a filtration process using a Buchner funnel. The nanopapers Eu-NFC 1-4 with different thickness (0.023 mm, 1; 0.04 mm, 2; 0.081 mm, 3 and 0.1 mm, 4) possess a fibres with dimensions of approximately 50 nm in diameter and several micrometres in length. Those nanopapers exhibit excellent ultraviolet A (UVA; 320-400 nm) filter property and high optical transmittance (>73% at wavelength of 600 nm). The presence of Eu(TTA)3(H2O)2 in Eu-NFC nanopapers can block 97% UVA (at 348 nm) light and convert it into pure red emission (CIE: x = 0.663, y = 0.333) through the efficient triplet-triplet energy transfer process. The efficient red emission can significantly improve the photo-stability of β-diketones type UVA filter. It can sustain for 10 h without decomposition under UV irradiation at 365 nm, which makes it possible to be applied in UVA filters. Moreover, its low coefficient of thermal expansion (CTE: 6.39 ppm K-1 of nanocellulose), is superior to petroleum-based materials for red organic light-emitting devices.

Towards sustainable management of huntable migratory waterbirds in Europe

USGS Publications Warehouse

Madsen, Jesper; Guillemain, Matthieu; Nagy, Szabolcs; Defos du Rau, Pierre; Mondain-Monval, Jean-Yves; Griffin, Cy; Williams, James Henty; Bunnefeld, Nils; Czajkowski, Alexandre; Hearn, Richard; Grauer, Andreas; Alhainen, Mikko; Middleton, Angus; Johnson, Fred A.

2015-01-01

The EU Birds Directive and the African-Eurasian Waterbird Agreement provide an adequate legal framework for sustainable management of migratory waterbird populations. The main shortcoming of both instruments is that it leaves harvest decisions of a shared resource to individual Member States and Contracting Parties without providing a shared information base and mechanism to assess the impact of harvest and coordinate actions in relation to mutually agreed objectives. A recent update of the conservation status of waterbirds in the EU shows that almost half of the populations of species listed on Annex II of the Birds Directive have a declining short-term trend and over half of them are listed in Columns A and B of AEWA. This implies that their hunting could either only continue under the framework of an adaptive harvest management plan or their hunting should be regulated with the view of restoring them in favourable conservation status. We argue that a structured approach to decision-making (such as adaptive management) is needed, supported with adequate organisational structures at flyway scale. We review the experience with such an approach in North America and assess the applicability of a similar approach in the European context. We show there is no technical reason why adaptive harvest management could be not applied in the EU or even AEWA context. We demonstrate that an informed approach to setting allowable harvests does not require detailed demographic information. Essential to the process, however, are estimates of either the observed growth rate from a monitoring program or the growth rate expected under ideal conditions. In addition, periodic estimates of population size are needed, as well as either empirical information or reasonable assumptions about the form of density dependence. We show that such information exists for many populations, but improvements are needed to improve geographic coverage, reliability and timely data availability. We highlight the importance of the International Waterbird Census and specialised goose and seaduck monitoring in estimating population sizes and observed growth rate of the populations. We encourage further investments into the development of these schemes. We also recognise the importance of migration studies to improve our understanding of delineations of populations. We also highlight that, with a few exceptions, the available data does not allow the European Commission, competent authorities of the Members States or other AEWA Contracting Parties to assess levels of harvest and their sustainability and, therefore, regulate hunting accordingly. Therefore, we recommend that annual reporting on 2 harvest levels of waterbird populations would be gradually introduced in the EU and the AEWA region. We propose that future AEWA and EU action plans and management plans for Annex II species should apply the principles of adaptive harvest management framework and make provisions for setting up adequate monitoring and information management systems and organisational structures to manage the decision-making process. We suggest that internationally coordinated management structures are established to facilitate dialogue, learning and communication between stakeholders with different interests and cultural backgrounds.

Multilingualism among Brussels-Based Civil Servants and Lobbyists: Perceptions and Practices

ERIC Educational Resources Information Center

Krizsán, Attila; Erkkilä, Tero

2014-01-01

This article explores the multilingual and multicultural aspects of community-building, networking and communication in the European Union's (EU) political and administrative system. We investigated the networking and communicative preferences of EU civil servants and lobbyists using survey data and thematic interviews. Our aim was to gain a…

Effects of composition modulation on the luminescence properties of Eu(3+) doped Li1-xAgxLu(MoO4)2 solid-solution phosphors.

PubMed

Cheng, Fangrui; Xia, Zhiguo; Molokeev, Maxim S; Jing, Xiping

2015-11-07

Double molybdate scheelite-type solid-solution phosphors Li1-xAgxLu1-y(MoO4)2:yEu(3+) were synthesized by the solid state reaction method, and their crystal structures and luminescence properties were investigated in detail. The composition modulation and structural evolution of this series of samples were studied and the selected AgEu(MoO4)2, AgLu(MoO4)2, LiLu(MoO4)2 and LiEu(MoO4)2 phases were analyzed based on the Rietveld refinement. Depending on the variation of the Li/Ag ratio in Li1-xAgxLu1-y(MoO4)2:yEu(3+) phosphors, the difference in the luminescence properties of Li1-xAgxLu1-y(MoO4)2:yEu(3+) phosphors was ascribed to two factors, one reason could be assigned to the coupling effect and the nonradiative transition between the energy levels of LixAg1-xLu(MoO4)2 matrices and the activator Eu(3+), another could be due to the near ultraviolet energy absorption and transmission efficiency between the charge-transfer (CT) band of O(2-)-Mo(6+) and the 4f → 4f emissive transitions of Eu(3+). The ultraviolet-visible diffuse reflection spectra (UV-vis DRS) and Raman spectra analysis were also used to verify the above mechanism.

Fabrication of SiO2@ZrO2@Y2O3:Eu3+ core-multi-shell structured phosphor.

PubMed

Gao, Xuan; He, Diping; Jiao, Huan; Chen, Juan; Meng, Xin

2011-08-01

ZrO2 interface was designed to block the reaction between SiO2 and Y2O3 in SiO2@Y2O3:Eu coreshell structure phosphor. SiO2@ZrO2@Y2O3:Eu core-multi-shell phosphors were successfully synthesized by combing an LBL method with a Sol-gel process. Based on electron microscopy, X-ray diffraction, and spectroscopy experiments, compelling evidence for the formation of the Y2O3:Eu outer shell on ZrO2 were presented. The presence of ZrO2 layer on SiO2 core can block the reaction of SiO2 core and Y2O3 shell effectively. By this kind of structure, the reaction temperature of the SiO2 core and Y2O3 shell in the SiO2@Y2O3:Eu core-shell structure phosphor can be increased about 200-300 degrees C and the luminescent intensity of this structure phosphor can be improved obviously. Under the excitation of ultraviolet (254 nm), the Eu3+ ion mainly shows its characteristic red (611 nm, 5D0-7F2) emissions in the core-multi-shell particles from Y2O3:Eu3+ shells. The emission intensity of Eu3+ ions can be tuned by the annealing temperatures, the number of coating times, and the thickness of ZrO2 interface, respectively.

Sr{sub 2}CaW{sub x}Mo{sub 1−x}O{sub 6}:Eu{sup 3+}, Li{sup +}: An emission tunable phosphor through site symmetry and excitation wavelength

DOE Office of Scientific and Technical Information (OSTI.GOV)

Xiao, Ning; Shen, Jun; Xiao, Tengjiao

2015-10-15

The emission of Eu{sup 3+} doped Sr{sub 2}CaW{sub x}Mo{sub 1−x}O{sub 6} phosphors could be tunable by the site symmetry of the activators and the excitation wavelengths. - Highlights: • The emission of Eu{sup 3+} depends on site symmetry and excitation wavelengths. • The color of the samples was tunable by structure and excitation wavelength. • The effect of W and Eu content on the properties of the samples was investigated. - Abstract: A series of Eu{sup 3+} substituted double-perovskite Sr{sub 2}CaW{sub x}Mo{sub 1−x}O{sub 6} phosphors were prepared by solid state reactions. The phase, photoluminescence and energy transfer of the phosphorsmore » were investigated by X-ray diffraction (XRD), photoluminescence (PL) and luminescence decay respectively. It is found that the emission of the Eu{sup 3+} substituted double perovskites depends on both the site symmetry of the activators and the excitation wavelengths. Based on the decay analysis of Sr{sub 2}CaW{sub x}Mo{sub 1−x}O{sub 6} matrix and Eu{sup 3+} doped samples, the energy transfer efficiencies between the host and activators Eu{sup 3+} were investigated. The results of the emission tunable phosphors indicate their potential applications in LEDs.« less

Pesticide authorization in the EU-environment unprotected?

PubMed

Stehle, Sebastian; Schulz, Ralf

2015-12-01

Pesticides constitute an integral part of high-intensity European agriculture. Prior to their authorization, a highly elaborated environmental risk assessment is mandatory according to EU pesticide legislation, i.e., Regulation (EC) No. 1107/2009. However, no field data-based evaluation of the risk assessment outcome, i.e., the regulatory acceptable concentrations (RACs), and therefore of the overall protectiveness of EU pesticide regulations exists. We conducted here a comprehensive meta-analysis using peer-reviewed literature on agricultural insecticide concentrations in EU surface waters and evaluated associated risks using the RACs derived from official European pesticide registration documents. As a result, 44.7 % of the 1566 cases of measured insecticide concentrations (MICs) in EU surface waters exceeded their respective RACs. It follows that current EU pesticide regulations do not protect the aquatic environment and that insecticides threaten aquatic biodiversity. RAC exceedances were significantly higher for insecticides authorized using conservative tier-I RACs and for more recently developed insecticide classes, i.e., pyrethroids. In addition, we identified higher risks, e.g., for smaller surface waters that are specifically considered in the regulatory risk assessment schemes. We illustrate the shortcomings of the EU regulatory risk assessment using two case studies that contextualize the respective risk assessment outcomes to field exposure. Overall, our meta-analysis challenges the field relevance and protectiveness of the regulatory environmental risk assessment conducted for pesticide authorization in the EU and indicates that critical revisions of related pesticide regulations and effective mitigation measures are urgently needed to substantially reduce the environmental risks arising from agricultural insecticide use.

Eu 3Ir 2In 15: A mixed-valent and vacancy-filled variant of the Sc 5Co 4Si 10 structure type with anomalous magnetic properties

DOE PAGES

Sarkar, Sumanta; Jana, Rajkumar; Siva, Ramesh; ...

2015-10-27

Here, a new compound, Eu 3Ir 2In 15 has been synthesized using indium as an active metal flux. The compound crystallizes in tetragonal P4/mbm space group with lattice parameters, a = 14.8580(4) Å, b = 14.8580(4) Å, c = 4.3901(2) Å. It was further characterized by SEM-EDX studies. The temperature dependent magnetic susceptibility suggests that Eu in this compound is exclusively in divalent state. The effective magnetic moment (μ eff) of this compound is 7.35 μ B/Eu ion with paramagnetic Curie temperature (θ p) of -28 K suggesting antiferromagnetic interaction. The mixed valent nature of Eu observed in magnetic measurementsmore » was confirmed by XANES measurements. The compound undergoes demagnetization at a low magnetic field (10 Oe), which is quite unusual for Eu based intermetallic compounds. Temperature dependent resistivity studies reveal that the compound is metallic in nature. A comparative study was made between Eu 3Ir 2In 15 and hypothetical vacancy variant Eu 5Ir 4In 10 which also crystallizes in the same crystal structure However our computational studies along with control experiments suggest that the latter is thermodynamically less feasible compared to the former and hence we proposed that it is highly unlikely that a RE 5T 4X 10 would exist with X as a group 13 elements.« less

Experimental comparison of high-density scintillators for EMCCD-based gamma ray imaging

NASA Astrophysics Data System (ADS)

Heemskerk, Jan W. T.; Kreuger, Rob; Goorden, Marlies C.; Korevaar, Marc A. N.; Salvador, Samuel; Seeley, Zachary M.; Cherepy, Nerine J.; van der Kolk, Erik; Payne, Stephen A.; Dorenbos, Pieter; Beekman, Freek J.

2012-07-01

Detection of x-rays and gamma rays with high spatial resolution can be achieved with scintillators that are optically coupled to electron-multiplying charge-coupled devices (EMCCDs). These can be operated at typical frame rates of 50 Hz with low noise. In such a set-up, scintillation light within each frame is integrated after which the frame is analyzed for the presence of scintillation events. This method allows for the use of scintillator materials with relatively long decay times of a few milliseconds, not previously considered for use in photon-counting gamma cameras, opening up an unexplored range of dense scintillators. In this paper, we test CdWO4 and transparent polycrystalline ceramics of Lu2O3:Eu and (Gd,Lu)2O3:Eu as alternatives to currently used CsI:Tl in order to improve the performance of EMCCD-based gamma cameras. The tested scintillators were selected for their significantly larger cross-sections at 140 keV (99mTc) compared to CsI:Tl combined with moderate to good light yield. A performance comparison based on gamma camera spatial and energy resolution was done with all tested scintillators having equal (66%) interaction probability at 140 keV. CdWO4, Lu2O3:Eu and (Gd,Lu)2O3:Eu all result in a significantly improved spatial resolution over CsI:Tl, albeit at the cost of reduced energy resolution. Lu2O3:Eu transparent ceramic gives the best spatial resolution: 65 µm full-width-at-half-maximum (FWHM) compared to 147 µm FWHM for CsI:Tl. In conclusion, these ‘slow’ dense scintillators open up new possibilities for improving the spatial resolution of EMCCD-based scintillation cameras.

NaEuF4/Au@Ag2S nanoparticles-based fluorescence resonant transfer DNA sensor for ultrasensitive detection of DNA energy.

PubMed

Liu, Yuhong; Zhao, Linlin; Zhang, Jin; Zhang, Jinzha; Zhao, Wenbo; Mao, Chun

2016-12-01

The work investigates a new fluorescence resonance energy transfer (FRET) system using NaEuF 4 nanoparticles (NPs) and Au@Ag 2 S NPs as the energy donor-acceptor pair for the first time. The NaEuF 4 /Au@Ag 2 S NPs-based FRET DNA sensor was constructed with NaEuF 4 NPs as the fluorescence (FL) donor and Au@Ag 2 S core-shell NPs as FL acceptor. In order to find the matching energy acceptor, the amount of AgNO 3 and Na 2 S were controlled in the synthesis process to overlap the absorption spectrum of energy acceptor with the emission spectrum of energy donors. The sensitivity of FRET-based DNA sensor can be enhanced and the self-absorption of ligand as well as the background of signals can be decreased because of Eu 3+ which owns large Stokes shifts and narrow emission bands due to f-f electronic transitions of 4f shell. We obtained the efficient FRET system by studying suitable distance between the donor and acceptor. Then the FRET-based DNA sensor was used for the design of specific and sensitive detection of target DNA and the quenching efficiency (ΔFL/F 0 , ΔFL=F-F 0 ) of FL was logarithmically related to the concentration of the target DNA, ranging from 100aM to 100pM. We can realize an ultrasensitive detection of target DNA with a detection limit of 32 aM. This proposed method was feasible to analyse target DNA in real samples with satisfactory results. Copyright © 2016 Elsevier B.V. All rights reserved.

Carbon prices and incentives for technological development.

PubMed

Lundgren, Tommy; Marklund, Per-Olov; Samakovlis, Eva; Zhou, Wenchao

2015-03-01

There is concern that the carbon prices generated through climate policies are too low to create the incentives necessary to stimulate technological development. This paper empirically analyzes how the Swedish carbon dioxide (CO2) tax and the European Union emission trading system (EU ETS) have affected productivity development in the Swedish pulp and paper industry 1998-2008. A Luenberger total factor productivity (TFP) indicator is computed using data envelopment analysis. The results show that climate policy had a modest impact on technological development in the pulp and paper industry, and if significant it was negative. The price of fossil fuels, on the contrary, seems to have created important incentives for technological development. Hence, the results suggest that the carbon prices faced by the industry through EU ETS and the CO2 tax have been too low. Even though the data for this study is specific for Sweden, the models and results are applicable internationally. When designing policy to mitigate CO2 emissions, it is vital that the policy creates a carbon price that is high enough - otherwise the pressure on technological development will not be sufficiently strong. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exploring the link between environmental pollution and economic growth in EU-28 countries: Is there an environmental Kuznets curve?

PubMed Central

Armeanu, Daniel; Vintilă, Georgeta; Gherghina, Ştefan Cristian; Drăgoi, Mihaela Cristina; Teodor, Cristian

2018-01-01

This study examines the Environmental Kuznets Curve hypothesis (EKC), considering the primary energy consumption among other country-specific variables, for a panel of the EU-28 countries during the period 1990–2014. By estimating pooled OLS regressions with Driscoll-Kraay standard errors in order to account for cross-sectional dependence, the results confirm the EKC hypothesis in the case of emissions of sulfur oxides and emissions of non-methane volatile organic compounds. In addition to pooled estimations, the output of fixed-effects regressions with Driscoll-Kraay standard errors support the EKC hypothesis for greenhouse gas emissions, greenhouse gas emissions intensity of energy consumption, emissions of nitrogen oxides, emissions of non-methane volatile organic compounds and emissions of ammonia. Additionally, the empirical findings from panel vector error correction model reveal a short-run unidirectional causality from GDP per capita growth to greenhouse gas emissions, as well as a bidirectional causal link between primary energy consumption and greenhouse gas emissions. Furthermore, since there occurred no causal link between economic growth and primary energy consumption, the neo-classical view was confirmed, namely the neutrality hypothesis. PMID:29742169

Exploring the link between environmental pollution and economic growth in EU-28 countries: Is there an environmental Kuznets curve?

PubMed

Armeanu, Daniel; Vintilă, Georgeta; Andrei, Jean Vasile; Gherghina, Ştefan Cristian; Drăgoi, Mihaela Cristina; Teodor, Cristian

2018-01-01

This study examines the Environmental Kuznets Curve hypothesis (EKC), considering the primary energy consumption among other country-specific variables, for a panel of the EU-28 countries during the period 1990-2014. By estimating pooled OLS regressions with Driscoll-Kraay standard errors in order to account for cross-sectional dependence, the results confirm the EKC hypothesis in the case of emissions of sulfur oxides and emissions of non-methane volatile organic compounds. In addition to pooled estimations, the output of fixed-effects regressions with Driscoll-Kraay standard errors support the EKC hypothesis for greenhouse gas emissions, greenhouse gas emissions intensity of energy consumption, emissions of nitrogen oxides, emissions of non-methane volatile organic compounds and emissions of ammonia. Additionally, the empirical findings from panel vector error correction model reveal a short-run unidirectional causality from GDP per capita growth to greenhouse gas emissions, as well as a bidirectional causal link between primary energy consumption and greenhouse gas emissions. Furthermore, since there occurred no causal link between economic growth and primary energy consumption, the neo-classical view was confirmed, namely the neutrality hypothesis.

Electron tunneling transport across heterojunctions between europium sulfide and indium arsenide

NASA Astrophysics Data System (ADS)

Kallaher, Raymond L.

This dissertation presents research done on utilizing the ferromagnetic semiconductor europium sulfide (EuS) to inject spin polarized electrons into the non-magnetic semiconductor indium arsenide (InAs). There is great interest in expanding the functionality of modern day electronic circuits by creating devices that depend not only on the flow of charge in the device, but also on the transport of spin through the device. Within this mindset, there is a concerted effort to establish an efficient means of injecting and detecting spin polarized electrons in a two dimensional electron system (2DES) as the first step in developing a spin based field effect transistor. Thus, the research presented in this thesis has focused on the feasibility of using EuS, in direct electrical contact with InAs, as a spin injecting electrode into an InAs 2DES. Doped EuS is a concentrated ferromagnetic semiconductor, whose conduction band undergoes a giant Zeeman splitting when the material becomes ferromagnetic. The concomitant difference in energy between the spin-up and spin-down energy bands makes the itinerant electrons in EuS highly spin polarized. Thus, in principle, EuS is a good candidate to be used as an injector of spin polarized electrons into non-magnetic materials. In addition, the ability to adjust the conductivity of EuS by varying the doping level in the material makes EuS particularly suited for injecting spins into non-magnetic semiconductors and 2DES. For this research, thin films of EuS have been grown via e-beam evaporation of EuS powder. This growth technique produces EuS films that are sulfur deficient; these sulfur vacancies act as intrinsic electron donors and the resulting EuS films behave like heavily doped ferromagnetic semiconductors. The growth parameters and deposition procedures were varied and optimized in order to fabricate films that have minimal crystalline defects. Various properties and characteristics of these EuS films were measured and compared to those characteristics found in previous reported work on doped EuS crystals. In particular, the magnetic switching behavior of individual micro-fabricated EuS structures was investigated to determine what types of spintronic devices EuS is best suited for. These studies found that the crystalline anisotropy of EuS dominates the switching behavior in EuS thin film structures with minimum feature sizes greater than ˜5 mum. This, in conjunction with the relatively high resistance of junctions between EuS and semiconductors, restricts the use of two tandem EuS electrodes in all semiconductor spintronic devices that require independently switching ferromagnetic electrodes. Spin transport studies in InAs 2DES are particularly interesting because of the heterostructure's high electron mobility and tunable spin-orbit interactions. Detailed measurements of the electrical transport characteristics across the heterojunction formed between EuS and InAs were taken in order to investigate the spin transport characteristics across the junction. These measurements show that the electrical transport across the heterojunction, below the ferromagnetic transition temperature, is directly related to the magnetization of the EuS layer and thus the transport is dominated by the spin-dependent Schottky barrier formed in EuS. Using a simple theory developed for these junctions, the magnitude of the change in barrier height---half the Zeeman splitting of the conduction band in EuS---as found to be ˜0.22 eV. The electrical transport measurements of the heterojunction between EuS and InAs at temperatures well above the ferromagnetic transition temperature of EuS shows that there are at least two separate scattering mechanisms in these junctions. As expected, critical scattering is the dominate scattering mechanism in the strongly paramagnetic regime; however, unexpectedly, the data show that critical scattering is not the dominate mechanism at temperatures greater than ˜100 K. The high temperature electrical transport measurements of the EuS/InAs heterojunction, in conjunction with low temperature zero-bias conductance measurements on junctions between EuS and gold (Au), suggest that there exists an interfacial layer in series with the magnetic Schottky barrier in these EuS junctions. This interfacial layer is modeled and explained as resulting from a rather high concentration of defects at the interface between EuS and the counter electrode.

Crystallization and photoluminescence properties of α-RE2(WO4)3 (RE: Gd, Eu) in rare-earth tungsten borate glasses

NASA Astrophysics Data System (ADS)

Wang, Yong; Honma, Tsuyoshi; Komatsu, Takayuki

2013-03-01

Glasses with the compositions of 22.5RE2O3-47.5WO3-30B2O3 (mol%) (RE: Gd, Eu) were prepared by a conventional melt quenching method, and α-Gd2(WO4)3 and α-Eu2(WO4)3 crystals were synthesized through their crystallization. The two types of WO4 tetrahedra present in α-RE2(WO4)3 provide the Raman bands at 931-934 cm-1 for WIIO4 tetrahrdra with much distortions and at 946-950 cm-1 for WIO4 tetrahedra with a near regular symmetry. The crystallized samples containing α-Eu2(WO4)3 exhibit strong red emissions under the excitation at 396 and 467 nm, although the base glass has no photoluminescence emission. α-Gd2(WO4)3 and α-Eu2(WO4)3 crystals were patterned on the glass surface by irradiations of a continuous wave Yb:YVO4 fiber laser (wavelength: 1080 nm).

Synthesis and Luminescence Properties of Blue Na(Sr0.97-xCa(x))PO4:0.03Eu2+ Phosphors for White Light Emitting Diode Applications.

PubMed

Hakeem, D A; Park, K

2015-07-01

The crystal structure and luminescence properties of Na(Sr0.97-xCax)PO4:0.03Eu2+ (0 < x < 1.0) phosphors were studied, depending on the Ca2+ concentration. All the Na(Sr0.97-xCax)PO4:0.03Eu2+ phosphors had a hexagonal crystal structure. The excitation spectra of the prepared phosphors showed a broad band ranging from 250 to 420 nm, which arises due to the 4f-5d transitions of Eu2+ ions. Upon the excitation of 334 nm wavelength, the emission spectra showed a broad blue band ranging from 400 to 700 nm peaking at 450 nm. Among the prepared phosphors, the Na(Sr0.72Ca0.25)PO4:0.03Eu2+ showed the strongest emission intensity and could be applied as a blue emitting phosphor for UV-based w-LEDs.

NMR determination of an incommensurate helical antiferromagnetic structure in EuCo 2 As 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding, Q. -P.; Higa, N.; Sangeetha, N. S.

In this paper, we report 153Eu, 75As, and 59Co nuclear magnetic resonance (NMR) results on EuCo 2As 2 single crystal. Observations of 153Eu and 75As NMR spectra in zero magnetic field at 4.3 K below an antiferromagnetic (AFM) ordering temperature T N = 45 K and its external magnetic field dependence clearly evidence an incommensurate helical AFM structure in EuCo 2As 2. Furthermore, based on 59Co NMR data in both the paramagnetic and the incommensurate AFM states, we have determined the model-independent value of the AFM propagation vector k = (0,0,0.73 ± 0.07)2π/c, where c is the c lattice parameter.more » Finally, the incommensurate helical AFM state was characterized by only NMR data with model-independent analyses, showing NMR to be a unique tool for determination of the spin structure in incommensurate helical AFMs.« less

NMR determination of an incommensurate helical antiferromagnetic structure in EuCo 2 As 2

DOE PAGES

Ding, Q. -P.; Higa, N.; Sangeetha, N. S.; ...

2017-05-05

In this paper, we report 153Eu, 75As, and 59Co nuclear magnetic resonance (NMR) results on EuCo 2As 2 single crystal. Observations of 153Eu and 75As NMR spectra in zero magnetic field at 4.3 K below an antiferromagnetic (AFM) ordering temperature T N = 45 K and its external magnetic field dependence clearly evidence an incommensurate helical AFM structure in EuCo 2As 2. Furthermore, based on 59Co NMR data in both the paramagnetic and the incommensurate AFM states, we have determined the model-independent value of the AFM propagation vector k = (0,0,0.73 ± 0.07)2π/c, where c is the c lattice parameter.more » Finally, the incommensurate helical AFM state was characterized by only NMR data with model-independent analyses, showing NMR to be a unique tool for determination of the spin structure in incommensurate helical AFMs.« less

Conjugation of TbPO4·H2O-Based Nanowires with Immunoglobulin G for Bioimaging

NASA Astrophysics Data System (ADS)

Huong, Nguyen Thanh; Lien, Pham Thi; Hung, Nguyen Manh; Van, Nguyen Duc; Thuy, Tran Thi; Binh, Nguyen Thanh; Minh, Le Quoc

2016-05-01

The surface modification, functionalization, and conjugation of undoped and 11 at.% Eu3+-doped TbPO4 ·H2O nanowires by using silica, a thyocyanate functional group, and immunoglobulin G, respectively, are described in this paper. For the core layer of obtained conjugated nanowires, the undoped TbPO4 ·H2O exhibited characteristic photoluminescent green emission corresponding to 5 D 4 → 7 F J transitions ( J = 6, 5, 4, 3) while the incorporation of Eu3+ into TbPO4 ·H2O lattice was evidenced by Starks splitting transitions at 590, 615, 693 nm of Eu3+ ions for the case of 11 at.% Eu3+-doped TbPO4 ·H2O. The results also indicated that both immunoglobulin G-conjugated undoped and Eu3+-doped TbPO4 ·H2O nanowires can be used in the fluorescent immune analysis as a biomedical label maker to identify measles viruses in vaccine testing.

Synthesis, structural and optical properties of BaMoO{sub 4}:Eu{sup 3+} shuttle like phosphors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Krishna Bharat, L.; Lee, Soo Hyun; Yu, Jae Su, E-mail: jsyu@khu.ac.kr

2014-05-01

Graphical abstract: - Highlights: • BaMoO{sub 4}:Eu{sup 3+} phosphors were synthesized by a facile synthesis route. • PL and CL spectra showed dominant emissions due to ({sup 5}D{sub 0} → {sup 7}F{sub 2}) hypersensitive transitions. • The excitation wavelengths in the UV-B region make BaMoO{sub 4}:Eu{sup 3+} phosphors as a good candidate in the red region for the development of UV-based white LEDs. • PL and CL spectra showed similar CIE values close to the commercially available Y{sub 2}O{sub 3}:Eu{sup 3+} phosphors. - Abstract: Eu{sup 3+} ions doped BaMoO{sub 4} phosphor samples were synthesized by a facile synthesis process. Themore » tetragonal phase of the host lattice was substantiated by the X-ray diffraction patterns. The morphological studies were carried out by taking the scanning electron microscope and transmission electron microscope images and confirmed the formation of shuttle like particles with perpendicular protrusions in the middle of the particle. The single crystalline nature of the phosphors was confirmed by the selected area electron diffraction pattern. The photoluminescence (PL) properties of the Eu{sup 3+} ions doped samples revealed good emission with a high asymmetry ratio when excited with ultraviolet B wavelengths (between 280 and 315 nm). The cathodoluminescence (CL) spectra showed similar results to the PL spectra. The calculated CIE values based on the PL and CL spectra were almost similar and confirmed the rich red emission.« less

Magnetic and structural properties of yellow europium oxide compound and Eu(OH){sub 3}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Dongwook, E-mail: dongwookleedl324@gmail.com; Seo, Jiwon, E-mail: jiwonseo@yonsei.ac.kr; Valladares, Luis de los Santos

A new material based on a yellow europium oxide compound was prepared from europium oxide in a high vacuum environment. The structural and magnetic properties of the material were investigated. Owing to the absence of a crystal structure, the material exhibited a disordered magnetic behavior. In a reaction with deionized (DI) water without applied heat, the compound assumed a white color as soon as the DI water reached the powder, and the structure became polycrystalline Eu(OH){sub 3}. The magnetic properties, such as the thermal hysteresis, disappeared after the reaction with DI water, and the magnetic susceptibility of the yellow oxidemore » compound weakened. The magnetic properties of Eu(OH){sub 3} were also examined. Although Eu{sup 3+} is present in Eu(OH){sub 3}, a high magnetic moment due to the crystal field effect was observed. - Graphical abstract: (top left) Optical image of the yellow europium oxide compound. (top right) Optical image of the product of DI water and yellow europium oxide. (bottom) Magnetization curves as a function of temperature measured in various magnetic field. - Highlights: • We prepared a new material based on a yellow europium oxide compound from europium oxide. • We characterized the magnetic properties of the material which exhibits a disordered magnetic behavior such as thermal hysteresis. • The compound turned white (Eu(OH){sub 3}) as soon as the DI water reached the powder. • The thermal hysteresis disappeared after the reaction with DI water and the magnetic susceptibility of the yellow oxide compound weakened.« less

Ab-initio calculation of EuO doped with 5% of (Ti, V, Cr and Fe): GGA and SIC approximation

NASA Astrophysics Data System (ADS)

Rouchdi, M.; Salmani, E.; Bekkioui, N.; Ez-Zahraouy, H.; Hassanain, N.; Benyoussef, A.; Mzerd, A.

2017-12-01

In this research, a simple theoretical method is proposed to investigate the electronic, magnetic and optical properties of Europium oxide (EuO) doped with 5% of (Ti, V, Cr and Fe). For a basic understanding of these properties, we employed Density-Functional Theory (DFT) based calculations with the Korringa-Kohn-Rostoker code (KKR) combined with the Coherent Potential Approximation (CPA). Also we investigated the half-metallic ferromagnetic behavior of EuO doped with 5% of (Ti, V, Cr and Fe) within the self-interaction-corrected Generalized Gradient Approximation (GGA-SIC). Our calculated results revealed that the Eu0.95TM0.05O is ferromagnetic with a high transition temperature. Moreover, the optical absorption spectra revealed that the half metallicity has been also predicted.

Second Wave of Biometric ID-documents in Europe: The Residence Permit for non-EU/EEA Nationals

NASA Astrophysics Data System (ADS)

Houdeau, Detlef

The first implementation of biometric documents, called biometric passports, based on a regulation is running, the second implementation since end of CY 2008 is coming to Europe. The focus is on persons staying for business, study or leisure for more than 3 months in Europe and coming from a state outside Europe and not being a member of the Visa-Waiver-Program of the EU. This second wave increases the demand for the security industry for certified security microcontroller chips, secure smart cards, readers and supporting infrastructure on top of the biometric Passport business. It underlines the continuing advance of contactless identification technology in the public sector. The article gives an overview on the application, the technology, the EU regulation, the EU roadmap and the implementations.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, Yoejin; Park, Sangmoon, E-mail: spark@silla.ac.kr

Graphical abstract: - Highlights: • New near-ultraviolet (NUV)-excitable materials composed of Ba{sub 9}Eu{sub m}Mn{sub n}Y{sub 2}Si{sub 6}O{sub 24} (m = 0.01–0.5, n = 0–0.7) were prepared. • High energy-transfer from Eu{sup 2+} to Mn{sup 2+} and their energy-transfer mechanism were discussed. • The co-doping of Eu{sup 2+} and Mn{sup 2+} in the orthosilicate structure resulted in the emission of white light under NUV LED light. - Abstract: New single-phase and near-ultraviolet (NUV)-excitable materials composed of Ba{sub 9}Eu{sub m}Mn{sub n}Y{sub 2}Si{sub 6}O{sub 24} (m = 0.01–0.5, n = 0–0.7) were prepared via a solid-state reaction in reducing atmosphere. X-ray diffraction patternsmore » of the obtained phosphors were examined to index the peak positions. After doping the host structure with Eu{sup 2+} and Mn{sup 2+} emitters, the intense green, white, and orange emission lights that were observed in the photoluminescence spectra under NUV excitation were monitored. The dependence of the luminescent intensity of the Mn{sup 2+} co-doped (n = 0.1–0.7) host lattices on the fixed Eu{sup 2+} content (m = 0.1, 0.3, 0.5) is also investigated. Co-doping Mn{sup 2+} into the Eu{sup 2+}-doped host structure enabled a high energy-transfer from Eu{sup 2+} to Mn{sup 2+} and their energy-transfer mechanism were discussed. Using these phosphors, the desired CIE values including emissions throughout the green to orange regions of the spectra were achieved. Efficient white-light light-emitting diodes (LEDs) were fabricated using Eu{sup 2+} and Mn{sup 2+} co-doped phosphors based on NUV-excitable LED lights.« less

Luminescence enhancement in Eu3+, Sm3+ co-doped liy(MoO4)2 nano-phosphors by sol-gel process.

PubMed

Zhou, Xianju; Wang, Guangchuan; Zhou, Tonghui; Zhou, Kaining; Li, Qingxu; Wang, Zhongqing

2014-05-01

A series of LiY(0.95-x)Eu(0.05)Sm(x)(MoO4)2 red light emitting phosphors were synthesized by sol-gel technique. The phase impurity and spectroscopic properties were characterized by X-ray Diffraction (XRD), Photo-Luminescence (PL) and Photo-Luminescence Excitation (PLE) spectra, respectively. It is found that the PLE spectra of the Eu3+, Sm3+ co-doped nanoparticles are enhanced and broadened as compared with the solely doped samples, which will make the co-doped phosphors match better with blue and/or UV GaN based LED chips. The red emission intensity of Eu3+ is largely enhanced by the energy transfer from Sm3+. The mechanism of the enhancement is clearly proven to be the increase in the quantum efficiency of 5D0 state of Eu3+ rather than the increase in the absorption of Eu3+. Meanwhile, the characteristic f-f transitions of Sm3+ are greatly reduced, resulting in little influence in the color purity of the co-doped phosphors. The present material is an amendatory promising red light emitting phosphor for white LEDs.

The EU sustainable energy policy indicators framework.

PubMed

Streimikiene, Dalia; Sivickas, Gintautas

2008-11-01

The article deals with indicators framework to monitor implementation of the main EU (European Union) directives and other policy documents targeting sustainable energy development. The main EU directives which have impact on sustainable energy development are directives promoting energy efficiency and use of renewable energy sources, directives implementing greenhouse gas mitigation and atmospheric pollution reduction policies and other policy documents and strategies targeting energy sector. Promotion of use of renewable energy sources and energy efficiency improvements are among priorities of EU energy policy because the use of renewable energy sources and energy efficiency improvements has positive impact on energy security and climate change mitigation. The framework of indicators can be developed to establish the main targets set by EU energy and environmental policies allowing to connect indicators via chain of mutual impacts and to define policies and measures necessary to achieve established targets based on assessment of their impact on the targeted indicators representing sustainable energy development aims. The article discusses the application of indicators framework for EU sustainable energy policy analysis and presents the case study of this policy tool application for Baltic States. The article also discusses the use of biomass in Baltic States and future considerations in this field.

NMR studies of the incommensurate helical antiferromagnet EuCo 2 P 2 : Determination of antiferromagnetic propagation vector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Higa, Nonoka; Ding, Qing -Ping; Yogi, Mamoru

Recently, Q.-P. Ding et al. reported that their nuclear magnetic resonance (NMR) study on EuCo 2As 2 successfully characterized the antiferromagnetic (AFM) propagation vector of the incommensurate helix AFM state, showing that NMR is a unique tool for determination of the spin structures in incommensurate helical AFMs. Motivated by this work, we have carried out 153Eu, 31P, and 59Co NMR measurements on the helical antiferromagnet EuCo 2P 2 with an AFM ordering temperature T N = 66.5 K. An incommensurate helical AFM structure was clearly confirmed by 153Eu and 31P NMR spectra on single-crystalline EuCo 2P 2 in zero magneticmore » field at 1.6 K and its external magnetic field dependence. Furthermore, based on 59Co NMR data in both the paramagnetic and incommensurate AFM states, we have determined the model-independent value of the AFM propagation vector k = (0,0,0.73±0.09)2π/c, where c is the c-axis lattice parameter. As a result, the temperature dependence of k is also discussed.« less

NMR studies of the incommensurate helical antiferromagnet EuCo 2 P 2 : Determination of antiferromagnetic propagation vector

DOE PAGES

Higa, Nonoka; Ding, Qing -Ping; Yogi, Mamoru; ...

2017-07-06

Recently, Q.-P. Ding et al. reported that their nuclear magnetic resonance (NMR) study on EuCo 2As 2 successfully characterized the antiferromagnetic (AFM) propagation vector of the incommensurate helix AFM state, showing that NMR is a unique tool for determination of the spin structures in incommensurate helical AFMs. Motivated by this work, we have carried out 153Eu, 31P, and 59Co NMR measurements on the helical antiferromagnet EuCo 2P 2 with an AFM ordering temperature T N = 66.5 K. An incommensurate helical AFM structure was clearly confirmed by 153Eu and 31P NMR spectra on single-crystalline EuCo 2P 2 in zero magneticmore » field at 1.6 K and its external magnetic field dependence. Furthermore, based on 59Co NMR data in both the paramagnetic and incommensurate AFM states, we have determined the model-independent value of the AFM propagation vector k = (0,0,0.73±0.09)2π/c, where c is the c-axis lattice parameter. As a result, the temperature dependence of k is also discussed.« less

Rethinking Sensitized Luminescence in Lanthanide Coordination Polymers and MOFs: Band Sensitization and Water Enhanced Eu Luminescence in [Ln(C15H9O5)3(H2O)3]n (Ln = Eu, Tb).

PubMed

Einkauf, Jeffrey D; Kelley, Tanya T; Chan, Benny C; de Lill, Daniel T

2016-08-15

A coordination polymer [Ln(C15H9O9)3(H2O)3]n (1-Ln = Eu(III), Tb(III)) assembled from benzophenonedicarboxylate was synthesized and characterized. The organic component is shown to sensitize lanthanide-based emission in both compounds, with quantum yields of 36% (Eu) and 6% (Tb). Luminescence of lanthanide coordination polymers is currently described from a molecular approach. This methodology fails to explain the luminescence of this system. It was found that the band structure of the organic component rather than the molecular triplet state was able to explain the observed luminescence. Deuterated (Ln(C15H9O9)3(D2O)3) and dehydrated (Ln(C15H9O9)3) analogues were also studied. When bound H2O was replaced by D2O, lifetime and emission increased as expected. Upon dehydration, lifetimes increased again, but emission of 1-Eu unexpectedly decreased. This reduction is reasoned through an unprecedented enhancement effect of the compound's luminescence by the OH/OD oscillators in the organic-to-Eu(III) energy transfer process.

A Multilevel Shape Fit Analysis of Neutron Transmission Data

NASA Astrophysics Data System (ADS)

Naguib, K.; Sallam, O. H.; Adib, M.; Ashry, A.

A multilevel shape fit analysis of neutron transmission data is presented. A multilevel computer code SHAPE is used to analyse clean transmission data obtained from time-of-flight (TOF) measurements. The shape analysis deduces the parameters of the observed resonances in the energy region considered in the measurements. The shape code is based upon a least square fit of a multilevel Briet-Wigner formula and includes both instrumental resolution and Doppler broadenings. Operating the SHAPE code on a test example of a measured transmission data of 151Eu, 153Eu and natural Eu in the energy range 0.025-1 eV accquired a good result for the used technique of analysis.Translated AbstractAnalyse von Neutronentransmissionsdaten mittels einer VielniveauformanpassungNeutronentransmissionsdaten werden in einer Vielniveauformanpassung analysiert. Dazu werden bereinigte Daten aus Flugzeitmessungen mit dem Rechnerprogramm SHAPE bearbeitet. Man erhält die Parameter der beobachteten Resonanzen im gemessenen Energiebereich. Die Formanpassung benutzt eine Briet-Wignerformel und berücksichtigt Linienverbreiterungen infolge sowohl der Meßeinrichtung als auch des Dopplereffekts. Als praktisches Beispiel werden 151Eu, 153Eu und natürliches Eu im Energiebereich 0.025 bis 1 eV mit guter Übereinstimmung theoretischer und experimenteller Werte behandelt.

Overview on Biofuels from a European Perspective

ERIC Educational Resources Information Center

Ponti, Luigi; Gutierrez, Andrew Paul

2009-01-01

In light of the recently developed European Union (EU) Biofuels Strategy, the literature is reviewed to examine (a) the coherency of biofuel production with the EU nonindustrial vision of agriculture, and (b) given its insufficient land base, the implications of a proposed bioenergy pact to grow biofuel crops in the developing world to meet EU…

Monitoring minimization of grade B environments based on risk assessment using three-dimensional airflow measurements and computer simulation.

PubMed

Katayama, Hirohito; Higo, Takashi; Tokunaga, Yuji; Katoh, Shigeo; Hiyama, Yukio; Morikawa, Kaoru

2008-01-01

A practical, risk-based monitoring approach using the combined data collected from actual experiments and computer simulations was developed for the qualification of an EU GMP Annex 1 Grade B, ISO Class 7 area. This approach can locate and minimize the representative number of sampling points used for microbial contamination risk assessment. We conducted a case study on an aseptic clean room, newly constructed and specifically designed for the use of a restricted access barrier system (RABS). Hotspots were located using three-dimensional airflow analysis based on a previously published empirical measurement method, the three-dimensional airflow analysis. Local mean age of air (LMAA) values were calculated based on computer simulations. Comparable results were found using actual measurements and simulations, demonstrating the potential usefulness of such tools in estimating contamination risks based on the airflow characteristics of a clean room. Intensive microbial monitoring and particle monitoring at the Grade B environmental qualification stage, as well as three-dimensional airflow analysis, were also conducted to reveal contamination hotspots. We found representative hotspots were located at perforated panels covering the air exhausts where the major piston airflows collect in the Grade B room, as well as at any locations within the room that were identified as having stagnant air. However, we also found that the floor surface air around the exit airway of the RABS EU GMP Annex 1 Grade A, ISO Class 5 area was always remarkably clean, possibly due to the immediate sweep of the piston airflow, which prevents dispersed human microbes from falling in a Stokes-type manner on settling plates placed on the floor around the Grade A exit airway. In addition, this airflow is expected to be clean with a significantly low LMAA. Based on these observed results, we propose a simplified daily monitoring program to monitor microbial contamination in Grade B environments. To locate hotspots we propose using a combination of computer simulation, actual airflow measurements, and intensive environmental monitoring at the qualification stage. Thereafter, instead of particle or microbial air monitoring, we recommend the use of microbial surface monitoring at the main air exhaust. These measures would be sufficient to assure the efficiency of the monitoring program, as well as to minimize the number of surface sampling points used in environments surrounding a RABS.

Investigation of doped Perovskite systems RAIO3 using density functional theory based electronic structure and thermoelectric studies

NASA Astrophysics Data System (ADS)

Sandeep; Rai, D. P.; Shankar, A.; Ghimire, M. P.; Thapa, R. K.

2016-10-01

Samarium doping effects on the thermoelectric properties in Eu1-xSmxAlO3 (x=0%, 50%, and 100%) were studied using first principles calculations based thermal transport property measurement. The result indicate that the compound is an intrinsic n-type material. Samarium doping has a positive effect on the overall thermoelectric performance of the Eu1-xSmxAlO3 system, with sharp increase in figure of merit (ZT) observed when x=0, 50 and 100% up to 150K. Compared to x=0 and 100%, the case of x=50% was found to have more positive increment in ZT value suggesting that the doing to have positive effect on figure of merit in Eu1-xSmxAlO3. Furthermore, all the samples show stable thermoelectric compatibility factors over a broad temperature range from 700 to 1000 K, which could have great benefits for their practical applications. It is concluded that the overall thermoelectric performance of the Eu1-xSmxAlO3 could be highly enhanced using doping techniques.

Lanthanide-doped NaGdF4 core-shell nanoparticles for non-contact self-referencing temperature sensors.

PubMed

Zheng, Shuhong; Chen, Weibo; Tan, Dezhi; Zhou, Jiajia; Guo, Qiangbing; Jiang, Wei; Xu, Cheng; Liu, Xiaofeng; Qiu, Jianrong

2014-06-07

We report that non-contact self-referencing temperature sensors can be realized with the use of core-shell nanostructures. These lanthanide-based nanothermometers (NaGdF4:Yb(3+)/Tm(3+)@Tb(3+)/Eu(3+)) exhibit higher sensitivity in a wide range from 125 to 300 K based on two emissions of Tb(3+) at 545 nm and Eu(3+) at 615 nm under near-infrared laser excitation.

Excitation-dependent local symmetry reversal in single host lattice Ba2A(BO3)2:Eu3+ [A = Mg and Ca] phosphors with tunable emission colours.

PubMed

Jayakiruba, S; Chandrasekaran, S Selva; Murugan, P; Lakshminarasimhan, N

2017-07-05

Eu 3+ activated phosphors are widely used as red emitters in various display devices and light emitting diodes (LEDs). The emission characteristics of Eu 3+ depend on the local site symmetry. The present study demonstrates the role of excitation-dependent local symmetry changes due to the structural reorganization on the emission colour tuning of Eu 3+ from orange-red to orange in single host lattices, Ba 2 Mg(BO 3 ) 2 and Ba 2 Ca(BO 3 ) 2 . The choice of these lattices was based on the difference in the extent of strain experienced by the oxygen atoms. The samples with Eu 3+ at Ba or Mg (Ca) sites were synthesized using the conventional high-temperature solid-state reaction method. The samples were characterized using powder XRD, 11 B MAS-NMR, FT-IR, and diffuse reflectance UV-Vis spectroscopic techniques. The room temperature photoluminescence (PL) recorded using different excitation wavelengths revealed a clear difference in the PL emission features due to symmetry reversal from non-inversion to inversion symmetry around Eu 3+ . The reorganization of highly strained oxygen atoms leads to such symmetry reversal. First-principles calculations were used to deduce the optimized structures of the two borate host lattices, and local geometries and their distortions upon Eu 3+ substitution. The outcomes of these calculations support the experimental findings.

Eu(III) Complexes of Octadentate 1-Hydroxy-2-pyridinones: Stability and Improved Photophysical Performance[].

PubMed

Moore, Evan G; D'Aléo, Anthony; Xu, Jide; Raymond, Kenneth N

2009-10-13

The luminescence properties of lanthanoid ions can be dramatically enhanced by coupling them to antenna ligands that absorb light in the UV/visible and then efficiently transfer the energy to the lanthanoid center. The synthesis and the complexation of Ln(III) cations (Ln=Eu; Gd) for a ligand based on four 1-hydroxy-2-pyridinone (1,2-HOPO) chelators appended to a ligand backbone derived by linking two L-lysine units (3LI-bis-LYS) is described. This octadentate Eu(III) complex ([Eu(3LI-bis-LYS-1,2-HOPO)](-)) has been evaluated in terms of its thermodynamic stability, UV/visible absorption and luminescence properties. For this complex the conditional stability constant (pM) is 19.9, which is an order of magnitude higher than diethylenetriaminepentacetic acid (DTPA) at pH= 7.4. This Eu(III) complex also shows an almost two-fold increase in its luminescence quantum yield in aqueous solution (pH= 7.4) when compared to other octadentate ligands. Hence, despite a slight decrease of the molar absorption coefficient, a much higher brightness is obtained for [Eu(3LI-bis-LYS-1,2-HOPO)](-). This overall improvement was achieved by saturating the coordination sphere of the Eu(III) cation, yielding an increased metal centered efficiency by excluding solvent water molecules from the metal's inner sphere.

Public health research support through the European structural funds in central and eastern Europe and the Mediterranean.

PubMed

McCarthy, Mark

2012-04-05

Public health research provides evidence for practice across fields including health care, health promotion and health surveillance. Levels of public health research vary markedly across European Union (EU) countries, and are lowest in the EU's new member states (in Central and Eastern Europe and the Mediterranean). However, these countries now receive most of the EU's Structural Funds, some of which are allocated to research. STEPS, an EU-funded study, sought to assess support for public health research at national and European levels. To identify support through the Structural funds, STEPS drew information from country respondents and internet searches for all twelve EU new member states. The EU allocates annually around €7 billion through the Structural Funds for member states' own use on research. These funds can cover infrastructure, academic employment, and direct research grants. The programmes emphasise links to business. Support for health research includes major projects in biosciences, but direct support for public health research was found in only three countries - Cyprus, Latvia and Lithuania. Public health research is not prioritised in the EU's Structural Funds programme in comparison with biomedicine. For the research dimension of the new European programme for Structural Funds 2014-2002, ministries of health should propose public health research to strengthen the evidence-base for European public health policy and practice.

Available Tools to Facilitate Early Patient Access to Medicines in the EU and the USA: Analysis of Conditional Approvals and the Implications for Personalized Medicine.

PubMed

Leyens, Lada; Richer, Étienne; Melien, Øyvind; Ballensiefen, Wolfgang; Brand, Angela

2015-01-01

Scientific knowledge and our understanding of the human body and diseases have limited any possible treatment tailoring to each patient. The technological advances enabling the integration of various data sets (e.g. '-omics', microbiome, epigenetics and environmental exposure) have facilitated a greater understanding of the human body, the molecular basis of disease and all the factors influencing disease onset, progression and response to treatment, thereby ushering in the era of personalized medicine. We evaluate the regulatory approaches available to facilitate early patient access to efficacious and safe compounds in the EU and the USA in order to make more informed recommendations in the future as to the gaps in regulations for early patient access. An in-depth analysis of conditional approvals (EU) and accelerated approvals (USA) is performed based on the publicly available information (European public assessment reports and a summary review of products approved under both programmes). The types of product, indications, time to approval and type of evidence submitted were analysed. Between 2007 and early 2015, 17 products were conditionally approved in the EU and 25 in the USA, most of them in the area of oncology and based on evidence from phase II clinical trial data. Early approval of promising products based on data from early phases of development is already possible in the EU and the USA. Some of the improvements could entail implementing a rolling assessment of evidence in Europe and extending the scope of early dialogues. © 2015 S. Karger AG, Basel.

A Double-Stimuli-Responsive Fluorescent Center for Monitoring of Food Spoilage based on Dye Covalently Modified EuMOFs: From Sensory Hydrogels to Logic Devices.

PubMed

Xu, Xiao-Yu; Lian, Xiao; Hao, Ji-Na; Zhang, Chi; Yan, Bing

2017-10-01

Unsafe food is a huge threat to human health and the economy, and detecting food spoilage early is an ongoing and imperative need. Herein, a simple and effective strategy combining a fluorescence sensor and one-to-two logic operation is designed for monitoring biogenic amines, indicators of food spoilage. Sensors (methyl red@lanthanide metal-organic frameworks (MR@EuMOFs)) are created by covalently modifying MR into NH 2 -rich EuMOFs, which have a high quantum yield (48%). A double-stimuli-responsive fluorescence center is produced via energy transfer from the ligands to Eu 3+ and MR. Portable sensory hydrogels are obtained by dispersing and solidifying MR@EuMOFs in water-phase sodium salt of carboxy methyl cellulose (CMC-Na). The hydrogels exhibit a color transition upon "smelling" histamine (HI) vapor. This transition and shift in the MR-based emission peak are closely related to the HI concentration. Using the HI concentration as the input signal and the two fluorescence emissions as output signals, an advanced analytical device based on a one-to-two logic gate is constructed. The four output combinations, NOT (0, 1), YES (1, 0), PASS 1 (1, 1), and PASS 0 (0, 0), allow the direct analysis of HI levels, which can be used for real-time food-freshness evaluation. The novel strategy suggested here may be a new application for a molecular logic system in the sensing field. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a ratiometric time-resolved luminescence sensor for pH based on lanthanide complexes.

PubMed

Liu, Mingjing; Ye, Zhiqiang; Xin, Chenglong; Yuan, Jingli

2013-01-25

Time-resolved luminescence bioassay technique using lanthanide complexes as luminescent probes/sensors has shown great utilities in clinical diagnostics and biotechnology discoveries. In this work, a novel terpyridine polyacid derivative that can form highly stable complexes with lanthanide ions in aqueous media, (4'-hydroxy-2,2':6',2''-terpyridine-6,6''-diyl) bis(methylenenitrilo) tetrakis(acetic acid) (HTTA), was designed and synthesized for developing time-resolved luminescence pH sensors based on its Eu(3+) and Tb(3+) complexes. The luminescence characterization results reveal that the luminescence intensity of HTTA-Eu(3+) is strongly dependent on the pH values in weakly acidic to neutral media (pK(a) = 5.8, pH 4.8-7.5), while that of HTTA-Tb(3+) is pH-independent. This unique luminescence response allows the mixture of HTTA-Eu(3+) and HTTA-Tb(3+) (the HTTA-Eu(3+)/Tb(3+) mixture) to be used as a ratiometric luminescence sensor for the time-resolved luminescence detection of pH with the intensity ratio of its Tb(3+) emission at 540 nm to its Eu(3+) emission at 610 nm, I(540 nm)/I(610 nm), as a signal. Moreover, the UV absorption spectrum changes of the HTTA-Eu(3+)/Tb(3+) mixture at different pHs (pH 4.0-7.0) also display a ratiometric response to the pH changes with the ratio of absorbance at 290 nm to that at 325 nm, A(290 nm)/A(325 nm), as a signal. This feature enables the HTTA-Eu(3+)/Tb(3+) mixture to have an additional function for the pH detection with the absorption spectrometry technique. For loading the complexes into the living cells, the acetoxymethyl ester of HTTA was synthesized and used for loading HTTA-Eu(3+) and HTTA-Tb(3+) into the cultured HeLa cells. The luminescence imaging results demonstrated the practical utility of the new sensor for the time-resolved luminescence cell imaging application. Copyright © 2012 Elsevier B.V. All rights reserved.

Novel and remarkable enhanced-fluorescence system based on gold nanoclusters for detection of tetracycline.

PubMed

Yang, Xiaoming; Zhu, Shanshan; Dou, Yao; Zhuo, Yan; Luo, Yawen; Feng, Yuanjiao

2014-05-01

Tetracycline and Eu(3+), while coexisting, usually appear as a complex by chelating. This complex shows low fluorescence intensity, leading to its limitation of analytical goals. Gold nanoclusters (AuNCs), emerging as novel nano-material, are attracting increasing attentions in multiple fields. Herein, gold nanoclusters first function as a fluorescence-enhanced reagent rather than a conventional fluorescent-probe, and a dramatic enhanced-fluorescence system was built based on Eu(3+)-Tetracycline complex (EuTC) by introducing gold nanoclusters. Simultaneously, three types of gold nanoclusters were employed for exploring various conditions likely affecting the system, which demonstrate that no other gold nanoclusters than DNA-templated gold nanoclusters enormously caused fluorescence-enhancement of EuTC. Moreover, this enhanced-fluorescence system permitted available detection of tetracycline (TC) in a linear range of 0.01-5 μM, with a detection limit of 4 nM at a signal-to-noise ratio of 3. Significantly, the practicality of this method for detection of TC in human urine and milk samples was validated, demonstrating its advantages of simplicity, sensitivity and low cost. Interestingly, this system described here is probably promising for kinds of applications based on its dramatically enhanced-fluorescence. © 2013 Published by Elsevier B.V.

Public health ethical perspectives on the values of the European Commission's White Paper "Together for Health".

PubMed

Schröder-Bäck, Peter; Clemens, Timo; Michelsen, Kai; Schulte in den Bäumen, Tobias; Sørensen, Kristine; Borrett, Glenn; Brand, Helmut

2012-06-01

In 2007 the European Commission issued the White Paper: "Together for Health". Considered the EU Health Strategy for the years 2008-2013, it offers the cornerstones for setting priorities in EU health actions. The public health framework offered in this strategy is explicitly built on shared values--including the overarching values of universality, access to good quality care, equity and solidarity that reacted to certain health care challenges within the EU. This article analyses the Health Strategy via its ethical scope and considers implications for future health policy making. The Health Strategy and related documents are scrutinised to explore how the mentioned values are defined and enfolded. Additionally, scientific databases are searched for critical discussions of the value base of the Health Strategy. The results are discussed and reasoned from a public health ethical perspective. The Health Strategy is barely documented and discussed in the scientific literature. Furthermore, no attention was given to the value base of the Health Strategy. Our analysis shows that the mentioned values are particularly focussed on health care in general rather than on public health in particular. Besides this, the given values of the Health Strategy are redundant. An additional consideration of consequentialist public health ethics values would normatively strengthen a population-based health approach of EU health policy making.

The origins of the bioeconomy in the European Union.

PubMed

Patermann, Christian; Aguilar, Alfredo

2018-01-25

This article outlines the context and circumstances that favoured the development of a Bioeconomy Strategy in the European Union (EU) and the role played by the different Framework programmes for Research, Technological Development and Demonstration. Particular attention is given to the biotechnology related programmes and more specifically to the "Cell Factory" Key Action in the 5th Framework Programme (1998-2002). This, together with the parallel development of a Strategy on Biotechnology in 2002, served as a solid foundation for the creation of the, at the time, so-called Knowledge-Based Bio-Economy (KBBE). The KBBE concept emerged in 2005, a couple of years before the launch of the 7th Framework Programme (2007-2013). The experience accumulated over the years and the new societal expectations triggered the EU to launch a Strategy on Bioeconomy in 2012. This article concludes with a brief analysis of the two most important impacts of the EU Strategy on Bioeconomy. One is the Bioeconomy dedicated activity within the Programme Horizon 2020 (2014-2020), and the other the creation of a public-private partnership of bio-based industries. Both the impact of Horizon 2020 on the EU Bioeconomy Strategy and the bio-based industries public-private partnership are analysed in depth in two articles elsewhere in this volume. Copyright © 2017 Elsevier B.V. All rights reserved.

Magnetism of europium under extreme pressures

DOE PAGES

Bi, W.; Lim, J.; Fabbris, G.; ...

2016-05-19

Using synchrotron-based Mossbauer and x-ray emission spectroscopies, we explore the evolution of magnetism in elemental (divalent) europium as it gives way to superconductivity at extreme pressures. Magnetic order in Eu is observed to collapse just above 80 GPa as superconductivity emerges, even though Eu cations retain their strong local 4f(7) magnetic moments up to 119 GPa with no evidence for an increase in valence. We speculate that superconductivity in Eu may be unconventional and have its origin in magnetic fluctuations, as has been suggested for high-T-c cuprates, heavy fermions, and iron-pnictides.

Diversity and dynamics of patient cost-sharing for physicians' and hospital services in the 27 European Union countries.

PubMed

Tambor, Marzena; Pavlova, Milena; Woch, Piotr; Groot, Wim

2011-10-01

During the past decades, many governments have introduced patient cost-sharing in their public health-care system. This trend in health-care reforms affected the European Union (EU) member states as well. This article presents a review of patient cost-sharing for health-care services in the 27 EU countries, and discusses directions for their improvement. Data are collected based on a review of international data bases, national laws and regulations, as well as scientific and policy reports. The analysis presents a combination of qualitative and quantitative research techniques. Patient cost-sharing arrangements in the EU have been changing considerably over the past two decades (mostly being extended) and are quite diverse at present. There is a relation between patient cost-sharing arrangements and some characteristics of the health-care system in a country. In a few EU countries, a mix of formal and informal charges exists, which creates a double financial burden for health-care consumers. The adequacy of patient cost-sharing arrangements in EU countries needs to be reconsidered. Most importantly, it is essential to deal with informal patient payments (where applicable) and to assure adequate exemption mechanisms to diminish the adverse equity effects of patient cost-sharing. A close communication with the public is needed to clarify the objectives and content of a patient payment policy in a country.

Evaluation of post-authorization safety studies in the first cohort of EU Risk Management Plans at time of regulatory approval.

PubMed

Giezen, Thijs J; Mantel-Teeuwisse, Aukje K; Straus, Sabine M J M; Egberts, Toine C G; Blackburn, Stella; Persson, Ingemar; Leufkens, Hubert G M

2009-01-01

Since November 2005, an EU Risk Management Plan (EU-RMP) has had to be submitted as part of a marketing application for all new chemical entities in the EU. In the EU-RMP, the safety profile of the medicine has to be described and pharmacovigilance activities should be proposed to study further safety concerns during use of the drug in the real-world setting. These activities include, for example, collection of spontaneously reported adverse events and post-authorization safety studies (PASS). Since the submission of an EU-RMP is a relatively new requirement, there is limited knowledge on the quality and completeness of the study protocols of PASS at the time of approval and there are no data on the influence of certain drug characteristics on the proposed pharmacovigilance activities. To examine the types of proposed pharmacovigilance activities in a sample of EU-RMPs, describe and evaluate the methodology of PASS, identify problems and propose remedies, and compare characteristics between biologicals and small molecules. Eighteen EU-RMPs (nine for biologicals, nine for small molecules) given a positive decision regarding the marketing application by the Committee for Medicinal Products for Human Use between November 2005 and May 2007 were included in this descriptive cohort study. The EU-RMPs were selected over time and different therapeutic areas. Classification of the safety concerns ('important identified risks', 'important potential risks', 'important missing information' within the EU-RMP was studied. For PASS, data source (registry, population-based database, sponsor-owned clinical trial database), source of study population to be included in PASS and comprehensiveness of study protocol (full protocol, limited protocol, study synopsis, short description, commitment without further information) were studied. Compared to small molecules, safety concerns for biologicals were less frequently classified as important identified risks (relative risk [RR] 0.6; 95% CI 0.3, 1.0) and more frequently as important missing information (RR 1.6; 95% CI 1.0, 2.7). Forty-seven PASS were proposed; 31 for biologicals and 16 for small molecules. Compared with studies proposed in population-based databases (4 for biologicals, 8 for small molecules), studies in registries (18 for biologicals, 4 for small molecules) were more frequently proposed for biologicals than for small molecules (RR 2.5; 95% CI 1.1, 5.7). About 60% of the proposed PASS will include EU inhabitants. No full study protocols were submitted; 26% involved a limited study protocol, 33% a study synopsis, 37% a short description and 4% a commitment without further information. Approximately 40% of the study proposals for PASS were classified as a short description or a commitment to perform a study without further information, precluding an adequate scientific assessment. Studying non-EU populations may give rise to difficulties with generalizability of the results to the EU due to differences in patient characteristics, differences in the indication for the medicine and different healthcare systems. This study emphasizes the need for more complete study proposals to be submitted earlier on in the evaluation period and for the inclusion of EU inhabitants in PASS. In addition, differences in the characteristics between biologicals and small molecules, e.g. in the data source proposed, support the need for individualized tailored PASS depending on the type of drug.

Spectroscopic study and enhanced thermostability of combustion-derived BaMgAl10O17:Eu2+ blue phosphors for solid-state lighting

NASA Astrophysics Data System (ADS)

Pradal, Nathalie; Potdevin, Audrey; Chadeyron, Geneviève; Bonville, Pierre; Caillier, Bruno; Mahiou, Rachid

2017-02-01

Blue-emitting BaMgAl10O17:Eu2+ (BAM:Eu), suitable for applications in a next generation of Hg-free lamps based on UV LEDs, was prepared by a microwave induced solution combustion synthesis, using urea as combustion fuel and nitrates as oxidizers. Purity control of the as-synthesized blue phosphor was undertaken by a washing step followed by a reduction one. Structural and morphological properties of the outcoming phosphors have been considered. Synthesis process allows producing a well-crystallized and nanostructured BAM phase within only few minutes. The influence of reduction treatment on the relative amounts of Eu2+/Eu3+ in our samples has been investigated through an original study by magnetization and Mössbauer spectroscopy. Furthermore, a complete optical study has been carried out and allowed us to determine the europium localization in the three possible sites in BAM matrix. The percentage of Eu2+ increased twofold after the reduction treatment, entailing an increase in the luminescence efficiency upon UV excitation. Finally, temperature-dependent luminescence of combustion-derived powders has been studied till 170 °C and compared to that of commercial BAM:Eu. MISCS-derived phosphors present a higher thermal stability than commercial one: whereas the emission efficiency of this last was reduced by 64%, the one of combustion-derived BAM:Eu experienced an only 12% decline. Furthermore, while commercial BAM suffered from a severe blue-shift with increasing temperature, our phosphors keep its color quality with a good stability of the photometric parameters.

Evolution of European Union legislation on emergency research.

PubMed

Mentzelopoulos, Spyros D; Mantzanas, Michail; van Belle, Gerald; Nichol, Graham

2015-06-01

Emergency research is necessary to prevent exposure of patients to unvalidated clinical practice (nonmaleficence), and to improve the dismal prognosis of disorders requiring emergent treatment such as cardiac arrest (beneficence). Regulations that govern clinical research should conform to bioethical principles of respect for nonmaleficence, beneficence, autonomy, and justice. Our objectives are to review the evolution of European Union (EU) legislation on emergency research, and to identify potentially remaining problems. EU legislative sources on clinical research and medical literature describing the impact of EU Regulations on emergency research. Article 5 of EU Directive 2001/20/EC required consent before enrolment in a research study to ensure the autonomy of potentially incapacitated research subjects. However, obtaining such consent is often impossible in emergency situations. Directive 2001/20/EC was criticized for potentially preventing emergency research. Several EU Member States addressed this problem by permitting deferred consent. International ethical guidelines supporting deferred consent were also cited by Good Clinical Practice Directive 2005/28/EC. However, Directive 2001/20/EC was not revised to achieve harmonization of EU emergency research, thus resulting in ongoing "ambiguity" as regards to emergency research legitimacy. This will be definitively addressed by applying EU Regulation No. 536/2014 and repealing Directive 2001/20/EC. The new EU Regulation permits using deferred consent under clearly specified conditions, and may foster emergency research that evaluates interventions posing minimal risk relative to standard practice. Legislation related to emergency research in Europe has evolved to increase concordance with bioethical principles so as to increase evidence-based improvements in emergency care. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Determination of soil degradation from flooding for estimating ecosystem services in Slovakia

NASA Astrophysics Data System (ADS)

Hlavcova, Kamila; Szolgay, Jan; Karabova, Beata; Kohnova, Silvia

2015-04-01

Floods as natural hazards are related to soil health, land-use and land management. They not only represent threats on their own, but can also be triggered, controlled and amplified by interactions with other soil threats and soil degradation processes. Among the many direct impacts of flooding on soil health, including soil texture, structure, changes in the soil's chemical properties, deterioration of soil aggregation and water holding capacity, etc., are soil erosion, mudflows, depositions of sediment and debris. Flooding is initiated by a combination of predispositive and triggering factors and apart from climate drivers it is related to the physiographic conditions of the land, state of the soil, land use and land management. Due to the diversity and complexity of their potential interactions, diverse methodologies and approaches are needed for describing a particular type of event in a specific environment, especially in ungauged sites. In engineering studies and also in many rainfall-runoff models, the SCS-CN method has remained widely applied for soil and land use-based estimations of direct runoff and flooding potential. The SCS-CN method is an empirical rainfall-runoff model developed by the USDA Natural Resources Conservation Service (formerly called the Soil Conservation Service or SCS). The runoff curve number (CN) is based on the hydrological soil characteristics, land use, land management and antecedent saturation conditions of soil. Since the method and curve numbers were derived on the basis of an empirical analysis of rainfall-runoff events from small catchments and hillslope plots monitored by the USDA, the use of the method for the conditions of Slovakia raises uncertainty and can cause inaccurate results in determining direct runoff. The objective of the study presented (also within the framework of the EU-FP7 RECARE Project) was to develop the SCS - CN methodology for the flood conditions in Slovakia (and especially for the RECARE pilot site of Myjava), with an emphasis on the determination of soil degradation from flooding for estimating ecosystem services. The parameters of the SCS-CN methodology were regionalised empirically based on actual rainfall and discharge measurements. Since there has been no appropriate methodology provided for the regionalisation of SCS-CN method parameters in Slovakia, such as runoff curve numbers and initial abstraction coefficients (λ), the work presented is important for the correct application of the SCS-CN method in our conditions.

Frequency upconversion and fluorescence intensity ratio method in Yb3+-ion-sensitized Gd2O3:Er3+-Eu3+ phosphors for display and temperature sensing

NASA Astrophysics Data System (ADS)

Ranjan, Sushil Kumar; Soni, Abhishek Kumar; Rai, Vineet Kumar

2017-09-01

Near infrared (NIR) to visible frequency upconversion emission studies in Er3+-Eu3+/Er3+-Eu3+-Yb3+ co-doped/tri-doped Gd2O3 phosphors prepared by the co-precipitation technique have been explored under 980 nm laser diode radiation. The developed phosphors were characterized with the help of XRD, FE-SEM and FTIR analysis. No upconversion (UC) emission was found in the Eu3+-doped Gd2O3 phosphor. UC emission from Eu3+ ions along with Er3+ ions was observed in Er3+-Eu3+ and Er3+-Eu3+-Yb3+ co-doped/tri-doped phosphors. The UC emission arising from the Er3+ and Eu3+ ions was enhanced several times due to the incorporation of Yb3+ ions. The processes involved in the UC emission were obtained on the basis of the effect of energy transfer/sensitization through the Yb3+ → Er3+ → Eu3+ process. The red/green intensity ratio was improved from 0.16 to 1.50 and 1.01 to 1.50 for Er3+-Eu3+-Yb3+ tri-doped phosphors as compared to the Er3+-doped and Er3+-Yb3+ co-doped phosphors, respectively, at a fixed pump power density. A UC fluorescence intensity ratio (FIR)-based temperature sensing study was performed in the prepared Er3+-Eu3+-Yb3+ tri-doped Gd2O3 phosphors for green upconversion emission bands in the 300 K-443 K temperature range. A maximum sensor sensitivity of about ˜0.0043 K-1 at 300 K was achieved for the synthesized tri-doped phosphors upon excitation with a 980 nm laser diode. The colour coordinates lying in the green-yellow region are invariant, with variation in pump power density and temperature. The observed results support the utility of the prepared tri-doped phosphors in optical temperature sensing, display devices and NIR to visible upconverters.

Divalent europium doped and un-doped calcium iodide scintillators: Scintillator characterization and single crystal growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boatner, L. A.; Ramey, J. O.; Kolopus, J. A.

2015-02-21

Initially, the alkaline-earth scintillator, CaI 2:Eu 2+, was discovered around 1964 by Hofstadter, Odell, and Schmidt. Serious practical problems quickly arose, however, that were associated with the growth of large monolithic single crystals of this material due to its lamellar, mica-like structure. As a result of its theoretically higher light yield, CaI 2:Eu 2+ has the potential to exceed the excellent scintillation performance of SrI 2:Eu 2+. In fact, theoretical predictions for the light yield of CaI2:Eu 2+ scintillators suggested that an energy resolution approaching 2% at 662 keV could be achievable. Like the early SrI 2:Eu 2+ scintillator, themore » performance of CaI 2:Eu 2+ scintillators has traditionally suffered due, at least in part, to outdated materials synthesis, component stoichiometry/purity, and single-crystal-growth techniques. Based on our recent work on SrI 2:Eu 2+ scintillators in single-crystal form, we have developed new techniques that are applied here to CaI 2:Eu 2+ and pure CaI 2 with the goal of growing large un-cracked crystals and, potentially, realizing the theoretically predicted performance of the CaI 2:Eu 2+ form of this material. Calcium iodide does not adhere to modern glassy carbon Bridgman crucibles - so there should be no differential thermal-contraction-induced crystal/crucible stresses on cooling that would result in crystal cracking of the lamellar structure of CaI 2. Here we apply glassy carbon crucible Bridgman growth, high-purity growth-charge compounds, our molten salt processing/filtration technique, and extended vacuum-melt-pumping methods to the growth of both CaI 2:Eu 2+ and un-doped CaI 2. Moreover, large scintillating single crystals were obtained, and detailed characterization studies of the scintillation properties of CaI 2:Eu 2+ and pure CaI 2 single crystals are presented that include studies of the effects of plastic deformation of the crystals on the scintillator performance.« less

Assessing Fire Weather Index using statistical downscaling and spatial interpolation techniques in Greece

NASA Astrophysics Data System (ADS)

Karali, Anna; Giannakopoulos, Christos; Frias, Maria Dolores; Hatzaki, Maria; Roussos, Anargyros; Casanueva, Ana

2013-04-01

Forest fires have always been present in the Mediterranean ecosystems, thus they constitute a major ecological and socio-economic issue. The last few decades though, the number of forest fires has significantly increased, as well as their severity and impact on the environment. Local fire danger projections are often required when dealing with wild fire research. In the present study the application of statistical downscaling and spatial interpolation methods was performed to the Canadian Fire Weather Index (FWI), in order to assess forest fire risk in Greece. The FWI is used worldwide (including the Mediterranean basin) to estimate the fire danger in a generalized fuel type, based solely on weather observations. The meteorological inputs to the FWI System are noon values of dry-bulb temperature, air relative humidity, 10m wind speed and precipitation during the previous 24 hours. The statistical downscaling methods are based on a statistical model that takes into account empirical relationships between large scale variables (used as predictors) and local scale variables. In the framework of the current study the statistical downscaling portal developed by the Santander Meteorology Group (https://www.meteo.unican.es/downscaling) in the framework of the EU project CLIMRUN (www.climrun.eu) was used to downscale non standard parameters related to forest fire risk. In this study, two different approaches were adopted. Firstly, the analogue downscaling technique was directly performed to the FWI index values and secondly the same downscaling technique was performed indirectly through the meteorological inputs of the index. In both cases, the statistical downscaling portal was used considering the ERA-Interim reanalysis as predictands due to the lack of observations at noon. Additionally, a three-dimensional (3D) interpolation method of position and elevation, based on Thin Plate Splines (TPS) was used, to interpolate the ERA-Interim data used to calculate the index. Results from this method were compared with the statistical downscaling results obtained from the portal. Finally, FWI was computed using weather observations obtained from the Hellenic National Meteorological Service, mainly in the south continental part of Greece and a comparison with the previous results was performed.

LOCAL MAGNETIC BEHAVIOR OF 54Fe in EuFe2As2 AND Eu0.5K0.5Fe2As2: MICROSCOPIC STUDY USING TIME DIFFERENTIAL PERTURBED ANGULAR DISTRIBUTION (TDPAD) SPECTROSCOPY

NASA Astrophysics Data System (ADS)

Mohanta, S. K.; Mishra, S. N.; Davane, S. M.; Layek, S.; Hossain, Z.

2013-12-01

In this paper, we report the time differential perturbed angular distribution measurements of 54Fe on a polycrystalline EuFe2As2 and Eu0.5K0.5Fe2As2. The hyperfine field and nuclear spin-relaxation rate are strongly temperature dependent in the paramagnetic state suggesting strong spin fluctuation in the parent compound. The local susceptibility show Curie-Weiss-like temperature dependence and Korringa-like relaxation in the tetragonal phase indicating the presence of local moment. In the orthorhombic phase, the hyperfine field behavior suggesting quasi two-dimensional magnetic ordering. The experimental results are in a good agreement with first-principle calculations based on density functional theory.

Direct transparent electrode patterning on layered GaN substrate by screen printing of indium tin oxide nanoparticle ink for Eu-doped GaN red light-emitting diode

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kashiwagi, Y., E-mail: kasiwagi@omtri.or.jp; Yamamoto, M.; Saitoh, M.

2014-12-01

Transparent electrodes were formed on Eu-doped GaN-based red-light-emitting diode (GaN:Eu LED) substrates by the screen printing of indium tin oxide nanoparticle (ITO np) inks as a wet process. The ITO nps with a mean diameter of 25 nm were synthesized by the controlled thermolysis of a mixture of indium complexes and tin complexes. After the direct screen printing of ITO np inks on GaN:Eu LED substrates and sintering at 850 °C for 10 min under atmospheric conditions, the resistivity of the ITO film was 5.2 mΩ cm. The fabricated LED up to 3 mm square surface emitted red light when the on-voltage was exceeded.

Direct transparent electrode patterning on layered GaN substrate by screen printing of indium tin oxide nanoparticle ink for Eu-doped GaN red light-emitting diode

NASA Astrophysics Data System (ADS)

Kashiwagi, Y.; Koizumi, A.; Takemura, Y.; Furuta, S.; Yamamoto, M.; Saitoh, M.; Takahashi, M.; Ohno, T.; Fujiwara, Y.; Murahashi, K.; Ohtsuka, K.; Nakamoto, M.

2014-12-01

Transparent electrodes were formed on Eu-doped GaN-based red-light-emitting diode (GaN:Eu LED) substrates by the screen printing of indium tin oxide nanoparticle (ITO np) inks as a wet process. The ITO nps with a mean diameter of 25 nm were synthesized by the controlled thermolysis of a mixture of indium complexes and tin complexes. After the direct screen printing of ITO np inks on GaN:Eu LED substrates and sintering at 850 °C for 10 min under atmospheric conditions, the resistivity of the ITO film was 5.2 mΩ cm. The fabricated LED up to 3 mm square surface emitted red light when the on-voltage was exceeded.

Systematic Site Characterization at Seismic Stations combined with Empirical Spectral Modeling: critical data for local hazard analysis

NASA Astrophysics Data System (ADS)

Michel, Clotaire; Hobiger, Manuel; Edwards, Benjamin; Poggi, Valerio; Burjanek, Jan; Cauzzi, Carlo; Kästli, Philipp; Fäh, Donat

2016-04-01

The Swiss Seismological Service operates one of the densest national seismic networks in the world, still rapidly expanding (see http://www.seismo.ethz.ch/monitor/index_EN). Since 2009, every newly instrumented site is characterized following an established procedure to derive realistic 1D VS velocity profiles. In addition, empirical Fourier spectral modeling is performed on the whole network for each recorded event with sufficient signal-to-noise ratio. Besides the source characteristics of the earthquakes, statistical real time analyses of the residuals of the spectral modeling provide a seamlessly updated amplification function w.r. to Swiss rock conditions at every station. Our site characterization procedure is mainly based on the analysis of surface waves from passive experiments and includes cross-checks of the derived amplification functions with those obtained through spectral modeling. The systematic use of three component surface-wave analysis, allowing the derivation of both Rayleigh and Love waves dispersion curves, also contributes to the improved quality of the retrieved profiles. The results of site characterisation activities at recently installed strong-motion stations depict the large variety of possible effects of surface geology on ground motion in the Alpine context. Such effects range from de-amplification at hard-rock sites to amplification up to a factor of 15 in lacustrine sediments with respect to the Swiss reference rock velocity model. The derived velocity profiles are shown to reproduce observed amplification functions from empirical spectral modeling. Although many sites are found to exhibit 1D behavior, our procedure allows the detection and qualification of 2D and 3D effects. All data collected during the site characterization procedures in the last 20 years are gathered in a database, implementing a data model proposed for community use at the European scale through NERA and EPOS (www.epos-eu.org). A web stationbook derived from it can be accessed through the interface www.stations.seismo.ethz.ch.

Contingency planning for Phytophthora ramorum outbreaks: progress report work package 7, EU RAPRA project

Treesearch

M.H.C.G. Steeghs

2008-01-01

As part of the EU project ?Risk analysis for Phytophthora ramorum, a recently recognised pathogen threat to Europe and the cause of Sudden Oak Death in the USA? (acronym RAPRA) outbreak scenarios are defined and existing strategies for eradication and containment of Phytophthora ramorum evaluated. Based on the current knowledge...

Habitus Conflicts and Experiences of Symbolic Violence as Obstacles for Non-Traditional Students

ERIC Educational Resources Information Center

Nairz-Wirth, Erna; Feldmann, Klaus; Spiegl, Judith

2017-01-01

Despite an expansion of educational opportunities throughout the EU, access to university is still distributed based on social inequality. This tendency can be observed in all EU countries, with Germany, Austria and Slovakia showing particularly low levels of upward mobility. Many working-class students or other non-traditional students never even…

Government Expenditures on Education as the Percentage of GDP in the EU

ERIC Educational Resources Information Center

Galetic, Fran

2015-01-01

This paper analyzes the government expenditures as the percentage of gross domestic product across countries of the European Union. There is a statistical model based on Z-score, whose aim is to calculate how much each EU country deviates from the average value. The model shows that government expenditures on education vary significantly between…

The Conversational Framework and the ISE "Basketball Shot" Video Analysis Activity

ERIC Educational Resources Information Center

English, Vincent; Crotty, Yvonne; Farren, Margaret

2015-01-01

Inspiring Science Education (ISE) (http://www.inspiringscience.eu/) is an EU funded initiative that seeks to further the use of inquiry-based science learning (IBSL) through the medium of ICT in the classroom. The Basketball Shot is a scenario (lesson plan) that involves the use of video capture to help the student investigate the concepts of…

Multi-Level Steering and Institution Building: The European Union's Approach to Research Policy

ERIC Educational Resources Information Center

Young, Mitchell

2012-01-01

Adopting the conception of the university as a primary driver of innovation and economic growth has brought increased pressure for the European Union (EU) to actively steer university-based research policy, despite its being outside of the EU's direct jurisdiction. While the open method of coordination (OMC) was developed for such situations, the…

"I Must Be Silent Because of Residency": Barriers to Escaping Domestic Violence in the Context of Insecure Immigration Status in England and Sweden.

PubMed

Voolma, Halliki

2018-02-01

This article draws on qualitative research examining domestic violence against women with insecure immigration status in England and Sweden. Empirical data were collected through in-depth semistructured interviews with 31 survivors from 14 non-European Union (EU) countries, and 57 professional stakeholders including 19 support service providers. This article reveals a multilayered process of actualizing women's right to live free from violence, with survivors required to be formally eligible for services according to their immigration status, having to prove their eligibility, overcome informal barriers including the fear of deportation, and gain access to accurate information about their rights and services.

Fiscal Year 2008 Phased Construction Completion Report for EU Z2-33 in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bechtel Jacobs

The Record of Decision for Soil, Buried Waste, and Subsurface Structure Actions in Zone 2, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2161&D2) (Zone 2 ROD) acknowledged that most of the 800 acres in Zone 2 were contaminated, but that sufficient data to confirm the levels of contamination were lacking. The Zone 2 ROD further specified that a sampling strategy for filling the data gaps would be developed. The Remedial Design Report/Remedial Action Work Plan for Zone 2 Soils, Slabs, and Subsurface Structures, East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2224&D3) (Zone 2 RDR/RAWP) defined the sampling strategy as themore » Dynamic Verification Strategy (DVS), generally following the approach used for characterization of the Zone 1 exposure units (EUs). The Zone 2 ROD divided the Zone 2 area into seven geographic areas and 44 EUs. To facilitate the data quality objectives (DQOs) of the DVS process, the Zone 2 RDR/RAWP regrouped the 44 EUs into 12 DQO scoping EU groups. These groups facilitated the DQO process by placing similar facilities and their support facilities together and allowing identification of data gaps. The EU groups were no longer pertinent after DQO planning was completed and characterization was conducted as areas became accessible. As the opportunity to complete characterization became available, the planned DVS program and remedial actions (RAs) were completed for EU Z2-33. Remedial action was also performed at two additional areas in adjacent EU Z2-42 because of their close proximity and similar nature to a small surface soil RA in EU Z2-33. Remedial actions for building slabs performed in EU Z2-33 during fiscal year (FY) 2007 were reported in the Fiscal Year 2007 Phased Construction Completion Report for the Zone 2 Soils, Slabs, and Subsurface Structures at East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2723&D1). Recommended RAs for EU Z2-42 were described in the Fiscal Year 2006 Phased Construction Completion Report for the Zone 2 Soils, Slabs, and Subsurface Structures at East Tennessee Technology Park, Oak Ridge, Tennessee (DOE/OR/01-2317&D2). Remedial actions performed in the Balance of Site (BOS) Laboratory Area of EU Z2-33 and two small areas in EU Z2-42 are described in Sects. 5 through 10 of this Phased Construction Completion Report (PCCR). The purpose of this PCCR is to address the following: (1) Document DVS characterization results for EU Z2-33; (2) Describe and document the risk evaluation and determine if the EU meets the Zone 2 ROD requirements for unrestricted industrial use to 10 ft bgs; (3) Identify additional areas not defined in the Zone 2 ROD that require remediation based on the DVS evaluation results; and (4) Describe RAs performed in the EU Z2-33 BOS Laboratory Area and two small areas in EU Z2-42. Approximately 18 acres in EU Z2-33 are addressed in this PCCR. Based on the results of the DVS evaluation and RAs performed, all 18 acres are recommended for unrestricted industrial use to 10 ft bgs. Three Federal Facility Agreement sites are addressed and recommended for no further action within this acreage, including: (1) K-1004-L Recirculating Cooling Water Lines Leak Sites; (2) K-1044 Heavy Equipment Repair Shop; and (3) K-1015-A Laundry Pit. Remedial actions for EU Z2-33 were developed in response to DVS characterization results described in the EU Z2-33 Technical Memorandum (Appendix A) and to support reindustrialization of the East Tennessee Technology Park as a commercial industrial park. Remediation criteria were designed for the protection of a future industrial worker who normally would not have the potential for exposure to soil below 10ft bgs. Accordingly, the Zone 2 ROD required land use controls to prevent disturbance of soils below 10 ft deep and to restrict future land use to industrial/commercial activities. In response to stakeholder comments, the U.S. Department of Energy agreed to re-evaluate the need for such land use restrictions. This document includes a screening evaluation to determine the likelihood of land use controls in EU Z2-33 being modified to: (1) eliminate the restriction on disturbance of soils below 10 ft bgs where data indicate the absence of residual contamination at any depth that would result in an unacceptable risk to the future industrial worker, and (2) permit alternative land uses that would be protective of future site occupants. Results of this screening evaluation indicate a low probability that restrictions on disturbing soil below 10 ft bgs could be safely eliminated for EU Z2-33. A qualitative screening evaluation considered the likelihood of unrestricted land use being protective of future site occupants. Based on this qualitative assessment, all 18 acres addressed in this PCCR were assigned a low probability for consideration of release for unrestricted land use.« less

Competence-Based Curricula in the Context of Bologna and EU Higher Education Policy

PubMed Central

Davies, Howard

2017-01-01

At the turn of the century European higher education policy became twin-track. The Bologna Process was launched and ran alongside developments in European legislation. Both tracks displayed a preoccupation with competences, in relation both to citizenship and to labour market needs. Scrutiny of important policy texts (Key Competences, the European Qualifications Framework, ECTS, the Bologna three-cycle degree structure) shows that ‘competence’ has never been given a precise and secure definition. Only very recently has the term entered the discourse of EU legislation on the recognition of professional qualifications. Current work on competence-based curricula in sectoral professions, including pharmacy, has helped bring the two policy tracks into closer alignment. The examples of competences identified in specific professional contexts can assist EU and Bologna policy-makers as they confront future challenges. PMID:28970429

Assessments of direct human exposure: the approach of EU risk assessments compared to scenario-based risk assessment.

PubMed

Wormuth, Matthias; Demou, Evangelia; Scheringer, Martin; Hungerbühler, Konrad

2007-08-01

The awareness of potential risks emerging from the use of chemicals in all parts of daily life has increased the need for risk assessments that are able to cover a high number of exposure situations and thereby ensure the safety of workers and consumers. In the European Union (EU), the practice of risk assessments for chemicals is laid down in a Technical Guidance Document; it is designed to consider environmental and human occupational and residential exposure. Almost 70 EU risk assessment reports (RARs) have been finalized for high-production-volume chemicals during the last decade. In the present study, we analyze the assessment of occupational and consumer exposure to trichloroethylene and phthalates presented in six EU RARs. Exposure scenarios in these six RARs were compared to scenarios used in applications of the scenario-based risk assessment approach to the same set of chemicals. We find that scenarios used in the selected EU RARs to represent typical exposure situations in occupational or private use of chemicals and products do not necessarily represent worst-case conditions. This can be due to the use of outdated information on technical equipment and conditions in workplaces or omission of pathways that can cause consumer exposure. Considering the need for exposure and risk assessments under the new chemicals legislation of the EU, we suggest that a transparent process of collecting data on exposure situations and of generating representative exposure scenarios is implemented to improve the accuracy of risk assessments. Also, the data sets used to assess human exposure should be harmonized, summarized in a transparent fashion, and made accessible for all risk assessors and the public.

Europium mixed-valence, long-range magnetic order, and dynamic magnetic response in EuCu 2 ( Si x Ge 1 - x ) 2

DOE PAGES

Nemkovski, Krill S.; Kozlenko, D. P.; Alekseev, Pavel A.; ...

2016-11-01

In mixed-valence or heavy-fermion systems, the hybridization between local f orbitals and conduction band states can cause the suppression of long-range magnetic order, which competes with strong spin uctuations. Ce- and Yb-based systems have been found to exhibit fascinating physical properties (heavy-fermion superconductivity, non-Fermi-liquid states, etc.) when tuned to the vicinity of magnetic quantum critical points by use of various external control parameters (temperature, magnetic eld, chemical composition). Recently, similar effects (mixed-valence, Kondo uctuations, heavy Fermi liquid) have been reported to exist in some Eu-based compounds. Unlike Ce (Yb), Eu has a multiple electron (hole) occupancy of its 4f shell,more » and the magnetic Eu 2+ state (4f 7) has no orbital component in the usual LS coupling scheme, which can lead to a quite different and interesting physics. In the EuCu 2(Si xGe 1-x) 2 series, where the valence can be tuned by varying the Si/Ge ratio, it has been reported that a significant valence uctuation can exist even in the magnetic order regime. This paper presents a detailed study of the latter material using different microscopic probes (XANES, Mossbauer spectroscopy, elastic and inelastic neutron scattering), in which the composition dependence of the magnetic order and dynamics across the series is traced back to the change in the Eu valence state. In particular, the results support the persistence of valence uctuations into the antiferromagnetic state over a sizable composition range below the critical Si concentration x c ≈ 0:65. In conclusion, the sequence of magnetic ground states in the series is shown to re ect the evolution of the magnetic spectral response.« less

Metaheuristics-Assisted Combinatorial Screening of Eu2+-Doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N Compositional Space in Search of a Narrow-Band Green Emitting Phosphor and Density Functional Theory Calculations.

PubMed

Lee, Jin-Woong; Singh, Satendra Pal; Kim, Minseuk; Hong, Sung Un; Park, Woon Bae; Sohn, Kee-Sun

2017-08-21

A metaheuristics-based design would be of great help in relieving the enormous experimental burdens faced during the combinatorial screening of a huge, multidimensional search space, while providing the same effect as total enumeration. In order to tackle the high-throughput powder processing complications and to secure practical phosphors, metaheuristics, an elitism-reinforced nondominated sorting genetic algorithm (NSGA-II), was employed in this study. The NSGA-II iteration targeted two objective functions. The first was to search for a higher emission efficacy. The second was to search for narrow-band green color emissions. The NSGA-II iteration finally converged on BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors in the Eu 2+ -doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N compositional search space. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor, which was synthesized with no human intervention via the assistance of NSGA-II, was a clear single phase and gave an acceptable luminescence. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor as well as all other phosphors that appeared during the NSGA-II iterations were examined in detail by employing powder X-ray diffraction-based Rietveld refinement, X-ray absorption near edge structure, density functional theory calculation, and time-resolved photoluminescence. The thermodynamic stability and the band structure plausibility were confirmed, and more importantly a novel approach to the energy transfer analysis was also introduced for BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors.

The Role of Defect Complexes in the Magneto-Optical Properties of Rare Earth Doped Gallium Nitride

NASA Astrophysics Data System (ADS)

Mitchell, Brandon

Wide band gap semiconductors doped with rare earth ions (RE) have shown great potential for applications in optoelectronics, photonics, and spintronics. The 1.54mum Erbium (Er) emission has been extensively utilized in optical fiber communications, and Europium (Eu) is commonly used as a red color component for LEDs and fluorescence lamps. For the realization of spintronic-type devices, a dilutely doped semiconductor that exhibits room temperature ferromagnetic behavior would be desirable. Such behavior has been observed in GaN:Er. Furthermore, it was demonstrated that strain may play an important role in the control of this ferromagnetism; however, this requires further investigation. One motivation of this work is the realization of an all solid state white light source monolithically integrated into III/V nitride semiconductor materials, ideally GaN. For this, the current AlGaAs-based LEDs need to be replaced. One approach for achieving efficient red emission from GaN is dilute doping with fluorescent ions. In this regard, Eu has consistently been the most promising candidate as a dopant in the active layer for a red, GaN based, LED due to the sharp 5D0 to 7F2 transitions that result in red emission around 620nm. The success of GaN:Eu as the active layer for a red LED is based on the ability for the Eu ions to be efficiently excited by electron hole pairs. Thus, the processes by which energy is transferred from the host to the Eu ions has been studied. Complications arise, however, from the fact that Eu ions incorporate into multiple center environments, the structures of which are found to have a profound influence on the excitation pathways and efficiencies of the Eu ion. Therefore the nature of Eu incorporation and the resulting luminescence efficiency in GaN has been extensively investigated. By performing a comparative study on GaN:Eu samples grown under a variety of controlled conditions and using a variety of experimental techniques, the majority site has been concluded to contain a nitrogen vacancy (V N) in its immediate structure. The nitrogen vacancy can appear in two symmetries, which has a profound impact on the luminescence and magnetic properties of the sample. The structure of the minority site has also been identified. For both sites, we give substantial evidence that the excitation efficiency of the red Eu emission is improved by the presence of donor-acceptor pairs in the vicinity of the Eu. Furthermore, when Mg was co-doped into GaN:Eu, additional incorporation environments were discovered that show high excitation efficiency at room temperature. These have been attributed to the coupling of Mg-H complexes to the majority Eu site. Electron beam irradiation, indirect and resonant (direct) laser excitation were found to modify these complexes, indicating that vibrational energy alone can trigger the migration of the H, while the presence of additional charges and excess energy controls the type of reconfiguration and the activation of non-radiative decay channels. We identify, experimentally, a two-step process in the dissociation of Mg-H complexes and propose, based on density functional theory, that the presence of minority carriers and the resulting charge states of complexes can also influence this process. In GaN:Er, we have given a more thorough overview of the optical and magneto-optical properties by extending to the 800nm excitation range and drastically improving the signal-to-noise ratio in the magnetic measurements, as well as applying a perpendicular magnetic field. This has allowed us to calculate g-factors for the parallel case, but revealed that the Zeeman interaction is not quite linear for perpendicular magnetic fields. We were able to assign crystal field numbers of mu = 3/2 to two crystal field levels. We have also given strong evidence that the strain in the sample, which results from lattice mismatch, enhances its magnetization, as seen through fluorescence line narrowing and asymmetry between the Zeeman transition intensities, under application of magnetic fields in anti-parallel directions.

European regulation model for herbal medicine: The assessment of the EU monograph and the safety and efficacy evaluation in marketing authorization or registration in Member States.

PubMed

Qu, Liping; Zou, Wenjun; Wang, YiTao; Wang, Mei

2018-03-15

The European Union (EU) has created a regulatory framework for herbal medicinal products (HMPs) since the enforcement of Directive 2004/24/EC. Substantial achievements have been made, with 1719 traditional use marketing registrations (TURs) and 859 well-established use marketing authorizations (WEU-MAs) for HMPs granted by the end of 2016. Apparently, the European regulation model has worked out well and in that the essential feature is the use of EU herbal monographs into those granted WEU-MAs and TURs. A systematic analysis of the European regulation model for HMPs and the EU herbal monograph's part of this model are undertaken to assist understanding of the EU legislation particularly for interested parties those from outside EU area, and afterwards, to help in decision-making in the HMPs registration in European market for pharmaceutical companies, as well as in the establishment of legislation in countries with strong traditional use of herbal remedies. A search of PubMed, ScienceDirect, the European Medicines Agency website and the Heads of Medicines Agencies website was conducted (up to December 2017), and the available information on regulation of HMPs in the EU was collected. The evaluation of applications by National Competent Authorities (NCAs) at a national level together with the assessment of EU monographs by the Committee on Herbal Medicinal Products (HMPC) at the European level constitute the European regulation framework for HMPs. As the scientific opinion about the safety and efficacy of HMPs from HMPC, the EU herbal monographs have been given a constitutional-based meaning to the TURs and WEU-MAs of HMPs and play a supportive function in the marketing procedure in Member States. The European framework has provided a powerful regulation model for harmonization of scientific assessment and facilitation of product marketing. For the pharmaceutical industries particularly those outside the EU, optimal use of the EU herbal monograph in their marketing procedure in Europe could be of great benefit. Furthermore, this model is well worth learning from for other countries and regions outside the EU to help the establishment of legislation in countries with strong traditional use of herbal remedies and contribute to the safe use of traditional herbal medicine. Copyright © 2018 Elsevier GmbH. All rights reserved.

Dual lanthanide-doped complexes: the development of a time-resolved ratiometric fluorescent probe for anthrax biomarker and a paper-based visual sensor.

PubMed

Wang, Qi-Xian; Xue, Shi-Fan; Chen, Zi-Han; Ma, Shi-Hui; Zhang, Shengqiang; Shi, Guoyue; Zhang, Min

2017-08-15

In this work, a novel time-resolved ratiometric fluorescent probe based on dual lanthanide (Tb: terbium, and Eu: europium)-doped complexes (Tb/DPA@SiO 2 -Eu/GMP) has been designed for detecting anthrax biomarker (dipicolinic acid, DPA), a unique and major component of anthrax spores. In such complexes-based probe, Tb/DPA@SiO 2 can serve as a stable reference signal with green fluorescence and Eu/GMP act as a sensitive response signal with red fluorescence for ratiometric fluorescent sensing DPA. Additionally, the probe exhibits long fluorescence lifetime, which can significantly reduce the autofluorescence interferences from biological samples by using time-resolved fluorescence measurement. More significantly, a paper-based visual sensor for DPA has been devised by using filter paper embedded with Tb/DPA@SiO 2 -Eu/GMP, and we have proved its utility for fluorescent detection of DPA, in which only a handheld UV lamp is used. In the presence of DPA, the paper-based visual sensor, illuminated by a handheld UV lamp, would result in an obvious fluorescence color change from green to red, which can be easily observed with naked eyes. The paper-based visual sensor is stable, portable, disposable, cost-effective and easy-to-use. The feasibility of using a smartphone with easy-to-access color-scanning APP as the detection platform for quantitative scanometric assays has been also demonstrated by coupled with our proposed paper-based visual sensor. This work unveils an effective method for accurate, sensitive and selective monitoring anthrax biomarker with backgroud-free and self-calibrating properties. Copyright © 2017 Elsevier B.V. All rights reserved.

Where are we coming from versus who we will become: the effect of priming different contents of European identity on cooperation.

PubMed

La Barbera, Francesco; Ferrara, Pia Cariota; Boza, Mihaela

2014-12-01

In two experiments, we investigated how priming European identity as common project versus common heritage affects participants' cooperation in a social dilemma; an additional aim was to explore the mediators involved in the process. In the first experiment, 82 students played a public good dilemma with a European bogus partner and then completed self-report measures of identification with the European Union (EU), group-based trust and collective interest. Results showed that priming a common project-based but not a common heritage-based European social identity fostered cooperative behaviour; this effect was mediated by two sequential mediators: the common project prime increased participants' strength of identification with EU (mediator 1) which, in turn, positively affected group-based trust (mediator 2), fostering greater cooperation. Experiment 2 was conducted with a similar procedure on a sample of 124 students, using a different measure of trust and changing the order of mediators. Results supported those of previous experiment: Priming a project-based EU identity content (compared to heritage-based one) had significant direct and indirect effects on cooperation. © 2014 International Union of Psychological Science.

Synthesis and photoluminescence of EuII in barium zinc orthosilicate: a novel green color emitting phosphor for white-LEDs.

PubMed

Kasturi, S; Sivakumar, V; Varadaraju, U V

2017-05-01

A series of Eu 2+ -activated barium orthosilicates (BaZnSiO 4 ) were synthesized using a high-temperature solid-state reaction. A photoluminescence excitation study of Eu 2 + shows a broad absorption band in the range of 270-450 nm, with multiple absorption peak maxima (310, 350 and 400 nm) due to 4f-5d electronic transition. The emission spectra of all the compositions show green color emission (in the spectral region 450-550 nm with a peak maximum at 502 nm and a shoulder at ~ 490 nm) with appropriate Comission Internationale de l'Eclairage (CIE) color coordinates. The two emission peaks are due to the presence of Eu 2 + in two different Ba sites in the BaZnSiO 4 host lattice. The energy transfers between the Eu 2 + ions in BaZnSiO 4 host are elucidated from the critical concentration quenching data based on the electronic multipolar interaction. All Eu 2 + -activated BaZnSiO 4 phosphor materials can be efficiently excited in the ultraviolet (UV) to near UV-region (270-420 nm), making them attractive candidate as a green phosphor for solid state lighting-white light-emitting diodes. Copyright © 2016 John Wiley & Sons, Ltd.

Surface Complexation Modeling of Eu(III) and U(VI) Interactions with Graphene Oxide.

PubMed

Xie, Yu; Helvenston, Edward M; Shuller-Nickles, Lindsay C; Powell, Brian A

2016-02-16

Graphene oxide (GO) has great potential for actinide removal due to its extremely high sorption capacity, but the mechanism of sorption remains unclear. In this study, the carboxylic functional group and an unexpected sulfonate functional group on GO were characterized as the reactive surface sites and quantified via diffuse layer modeling of the GO acid/base titrations. The presence of sulfonate functional group on GO was confirmed using elemental analysis and X-ray photoelectron spectroscopy. Batch experiments of Eu(III) and U(VI) sorption to GO as the function of pH (1-8) and as the function of analyte concentration (10-100, 000 ppb) at a constant pH ≈ 5 were conducted; the batch sorption results were modeled simultaneously using surface complexation modeling (SCM). The SCM indicated that Eu(III) and U(VI) complexation to carboxylate functional group is the main mechanism for their sorption to GO; their complexation to the sulfonate site occurred at the lower pH range and the complexation of Eu(III) to sulfonate site are more significant than that of U(VI). Eu(III) and U(VI) facilitated GO aggregation was observed with high Eu(III) and U(VI) concentration and may be caused by surface charge neutralization of GO after sorption.

Characterization of the Advanced Stirling Radioisotope Generator EU2

NASA Technical Reports Server (NTRS)

Lewandowski, Edward J.; Oriti, Salvatore M.; Schifer, Nicholas A.

2015-01-01

Significant progress was made developing the Advanced Stirling Radioisotope Generator (ASRG), a 140-watt radioisotope power system. While the ASRG flight development project has ended, the hardware that was designed and built under the project is continuing to be tested to support future Stirling-based power system development. NASA GRC recently completed the assembly of the ASRG Engineering Unit 2 (EU2). The ASRG EU2 consists of the first pair of Sunpower's ASC-E3 Stirling convertors mounted in an aluminum housing, and Lockheed Martin's Engineering Development Unit (EDU) 4 controller (a fourth generation controller). The ASC-E3 convertors and Generator Housing Assembly (GHA) closely match the intended ASRG Qualification Unit flight design. A series of tests were conducted to characterize the EU2, its controller, and the convertors in the flight-like GHA. The GHA contained an argon cover gas for these tests. The tests included: measurement of convertor, controller, and generator performance and efficiency, quantification of control authority of the controller, disturbance force measurement with varying piston phase and piston amplitude, and measurement of the effect of spacecraft DC bus voltage on EU2 performance. The results of these tests are discussed and summarized, providing a basic understanding of EU2 characteristics and the performance and capability of the EDU 4 controller.

White Light Emission and Enhanced Color Stability in a Single-Component Host.

PubMed

Li, Junhao; Liang, Qiongyun; Hong, Jun-Yu; Yan, Jing; Dolgov, Leonid; Meng, Yuying; Xu, Yiqin; Shi, Jianxin; Wu, Mingmei

2018-05-30

Eu 3+ ion can be effectively sensitized by Ce 3+ ion through an energy-transfer chain of Ce 3+ -(Tb 3+ ) n -Eu 3+ , which has contributed to the development of white light-emitting diodes (WLEDs) as it can favor more efficient red phosphors. However, simply serving for WLEDs as one of the multicomponents, the design of the Ce 3+ -(Tb 3+ ) n -Eu 3+ energy transfer is undoubtedly underused. Theoretically, white light can be achieved with extra blue and green emissions released from Ce 3+ and Tb 3+ . Herein, the design of the white light based on these three multicolor luminescence centers has been realized in GdBO 3 . It is the first time that white light is generated via accurate controls on the Ce 3+ -(Tb 3+ ) n -Eu 3+ energy transfer in such a widely studied host material. Because the thermal quenching rates of blue, green, and red emissions from Ce 3+ , Tb 3+ , and Eu 3+ , respectively, are well-matched in the host, this novel white light exhibits superior color stability and potential application prospect.

A Worldwide Web-portal for Aquatic Mesocosm Facilities: WWW.MESOCOSM.EU

NASA Astrophysics Data System (ADS)

Berger, S. A.; Nejstgaard, J. C.

2016-02-01

Experimental mesocosms are valuable tools to fill the gap between highly controlled/replicated lab experiments and uncontrolled/non-replicated natural environments such as rivers, lakes and oceans. WWW.MESOCOSM.EU is an open web-portal for leading aquatic mesocosm facilities around the world. It was created within the FP7 EU-project MESOAQUA (A network of leading MESOcosm facilities to advance the studies of future AQUAtic ecosystems from the Arctic to the Mediterranean). The goal of the portal is to increase international knowledge about existing mesocosm facilities, including information on locations, environment, equipment, contacts, research opportunities and mesocosm-based publications. MESOCOSM.EU specifically aims to be a tool to enhance the quality of research by facilitating international cooperative network building, announcement of new research initiatives, transfer of best practice, and dissemination of knowledge, public information and press releases. As an open platform for all aquatic ecosystem scale science (marine and freshwater), MESOCOSM.EU aims to fill the lack of a centralized, coordinating virtual infrastructure for international aquatic mesocosm research, from the mountains to the ocean and from polar to tropical regions.

The Role of Coordination Environment and pH in Tuning the Oxidation Rate of Europium(II).

PubMed

Ekanger, Levi A; Basal, Lina A; Allen, Matthew J

2017-01-23

The Eu II/III redox couple offers metal-based oxidation-sensing with magnetic resonance imaging making the study of Eu II oxidation chemistry important in the design of new probes. Accordingly, we explored oxidation reactions with a set of Eu II -containing complexes. Superoxide formation from the reaction between Eu II and dioxygen was observed using electron paramagnetic resonance spectroscopy. Additionally, oxidation kinetics of three Eu II -containing complexes with bromate and glutathione disulfide at pH values, including 5 and 7, is reported. In the reaction with bromate, the oxidation rate of two of the complexes increased by 7.3 and 6.7 times upon decreasing pH from 7 to 5, but the rate increased by 17 times for a complex containing amide functional groups over the same pH range. The oxidation rate of a fluorobenzo-functionalized cryptate was relatively slow, indicating that the ligand used to impart thermodynamic oxidative stability might also be useful for controlling oxidation kinetics. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Highlight report: Launch of a large integrated European in vitro toxicology project: EU-ToxRisk.

PubMed

Daneshian, Mardas; Kamp, Hennicke; Hengstler, Jan; Leist, Marcel; van de Water, Bob

2016-05-01

The integrated European project, EU-ToxRisk, proudly sees itself as "flagship" exploring new alternative-to-animal approaches to chemical safety evaluation. It promotes mechanism-based toxicity testing and risk assessment according to the principles laid down for toxicology for the twenty-first century. The project was officially launched in January 2016 with a kickoff meeting in Egmond aan Zee, the Netherlands. Over 100 scientists representing academia and industry as well as regulatory authorities attended the inaugural meeting. The project will integrate advances in in vitro and in silico toxicology, read-across methods, and adverse outcome pathways. EU-ToxRisk will continue to make use of the case study strategy deployed in SEURAT-1, a FP7 initiative ended in December 2015. Even though the development of new non-animal methods is one target of EU-ToxRisk, the project puts special emphasis on their acceptance and implementation in regulatory contexts. This €30 million Horizon 2020 project involves 38 European partners and one from the USA. EU-ToxRisk aims at the "development of a new way of risk assessment."

Europium-doped gadolinium sulfide nanoparticles as a dual-mode imaging agent for T1-weighted MR and photoluminescence imaging.

PubMed

Jung, Jongjin; Kim, Mi Ae; Cho, Jee-Hyun; Lee, Seung Jae; Yang, Ilseung; Cho, Janggeun; Kim, Seong Keun; Lee, Chulhyun; Park, Joung Kyu

2012-08-01

We present a facile synthesis of europium-doped gadolinium sulfide (GdS:Eu(3+)) opto-magnetic nanoparticles (NPs) via sonochemistry. Their photoluminescence and strong paramagnetic properties enable these NPs to be utilized as an in vitro cell imaging and in vivo T(1)-weighted MR imaging probe. The GdS:Eu(3+) NPs have a prominent longitudinal (r(1)) relaxivity value, which is a critical parameter for T(1)-weighted MR imaging. Here, we showed not only their strong positive contrast effect to blood vessels and organs of mice, but also blood half-life and biodistribution including clearance from organs, in order to assess the GdS:Eu(3+) NPs as a competent nanocrystal-based T(1) contrast agent. We further showed confocal images of breast cancer cells containing GdS:Eu(3+) NPs to evaluate as a photoluminescence probe. Dual-mode imaging capability obtained from the GdS:Eu(3+) NPs will allow target-oriented cellular imaging as well as the resulting disease-specific MR imaging. Copyright © 2012 Elsevier Ltd. All rights reserved.

Influence of MO/MF2 modifiers (M = Ca, Sr, Ba) on spectroscopic properties of Eu3+ ions in germanate and borate glasses

NASA Astrophysics Data System (ADS)

Zur, Lidia; Janek, Joanna; Pietrasik, Ewa; Sołtys, Marta; Pisarska, Joanna; Pisarski, Wojciech A.

2016-11-01

Series of Eu3+-doped lead-free germanate and borate glasses were synthesized. The MO glass modifiers (M = Ca, Sr or Ba) were partially or totally substituted by MF2 in chemical composition. In contrast to samples modified by CaO/CaF2 or SrO/SrF2, the germanate glass samples containing BaO and/or BaF2 are fully amorphous, while the lead-free borate glasses are fully amorphous, independently from glass modifiers. Effect of glass modifiers on spectroscopic properties of Eu3+ were systematically investigated. For that reason, excitation and emission spectra of Eu3+ ions in examined systems were registered. Based on the emission spectra, ratio of integrated luminescence intensity of the 5D0 → 7F2 transition to that of the 5D0 → 7F1 transition (R factor) was calculated. Moreover, the luminescence decay curves were collected and the luminescence lifetimes of the 5D0 excited state of Eu3+ ions were determined in function of MF2 concentration.

Molecular beam epitaxy of lead salt-based vertical cavity surface emitting lasers for the 4-6 μm spectral region

NASA Astrophysics Data System (ADS)

Springholz, G.; Schwarzl, T.; Heiß, W.; Aigle, M.; Pascher, H.

2001-07-01

IV-VI semiconductor vertical cavity surface emitting quantum well lasers (VCSELs) for the 4-6 μm spectral region were grown by molecular beam epitaxy on BaF 2 (1 1 1) substrates. The VCSEL structures consist of two Bragg mirrors with an active cavity region consisting of PbTe quantum wells inserted into Pb 1- xEu xTe as barrier material. For the Bragg mirrors, two different layer structures were investigated, namely, (A) the use of nearly lattice-matched ternary Pb 1- xEu xTe layers with Eu contents alternating between 1% and 6%, and (B) the use of EuTe and Pb 1- xEu xTe ( x=6%) as bilayer combination. The latter yields a much higher refractive index contrast but features a lattice-mismatch of about 2%. VCSEL structures of each Bragg mirror type were fabricated and optically pumped laser emission was obtained at 6.07 μm for VCSELs of type A and at 4.8 μm for that of type B with a maximum operation temperature of 85 K.

Synthesis and photoluminescence control of Ca{sub 10.5–1.5x}La{sub x}(PO{sub 4}){sub 7}:Eu{sup 2+} phosphors by aliovalent cation substitution

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fan, Yanting; Tang, Miao; Qiu, Zhongxian

A range of Ca{sub 10.5-1.5x}La{sub x}(PO{sub 4}){sub 7}:Eu{sup 2+}phosphors were synthesized by high temperature solid state method. Subsequently we studied the crystal structures and luminescent properties through X-ray diffraction, photoluminescence and photoluminescence excitation, diffuse reflection spectra, Raman spectra and decay curves systematically. Based on the special crystal structure ofβ-Ca{sub 3}(PO{sub 4}){sub 2}:Eu{sup 2+}, its emission undergoes a variation from violet–blue to cyan through introducing La{sup 3+}. The substitution of La{sup 3+} for Ca{sup 2+} could form some cation vacancies in Ca(4) sites according to the scheme 3Ca{sup 2+}= 2La{sup 3+}+ □ due to the different ion valence, which compels Eu{supmore » 2+} to migrate from Ca(4) site to other sites. Additionally, the formation of the cation vacancies can further reduce the thermal stability of phosphors. - Highlights: • Realizing photoluminescence control of Eu{sup 2+} by introducing relatively larger La{sup 3+} ion to replace the Ca{sup 2+} in β-Ca{sub 3}(PO{sub 4}){sub 2}:Eu{sup 2+} phosphor. • The mechanism of spectral control is proposed to be due to emptying of Ca{sup 2+} and migration of Eu{sup 2+}. • The thermal stability reduction is related to the formation of vacancies.« less

The EU pledge for responsible marketing of food and beverages to children: implementation in food companies.

PubMed

Jensen, J D; Ronit, K

2015-08-01

Increasing political pressure on the food industry's marketing activities stimulated the formation of the collective EU Pledge for responsible marketing of foods and beverages to children. The objective of the study is to evaluate the commitments made by companies in joining the pledge for the purpose of assessing its effectiveness in regulating signatory companies' marketing activities. Data on company commitments in relation to the EU Pledge were collected, analyzed and recalculated in order to enable comparison across companies and with general nutritional recommendations. Data on companies' product portfolio and market orientation were collected from their most recent available annual reports. Data on the companies' product profiles were generated via review of the companies' main websites. Similar data were generated for a reference group of companies outside the EU Pledge. Compared with a reference group of large food and beverage companies, EU Pledge signatory companies have a public image strongly based on products with appeal to children. The EU Pledge sets common standards for regulating signatory companies' marketing behaviour towards children. Further scrutiny of the companies' stated commitments revealed considerable variation in their actual content and in their de facto bindingness on the companies' marketing behavior--for example, in the definition of target audience for advertising or in nutritional characteristics making products eligible for advertising to children. In order for voluntary self-regulation schemes such as the EU Pledge to be a credible alternative to public regulation of marketing behaviour, more transparency and stringency are needed.

Luminescence in Sulfides: A Rich History and a Bright Future

PubMed Central

Smet, Philippe F.; Moreels, Iwan; Hens, Zeger; Poelman, Dirk

2010-01-01

Sulfide-based luminescent materials have attracted a lot of attention for a wide range of photo-, cathodo- and electroluminescent applications. Upon doping with Ce3+ and Eu2+, the luminescence can be varied over the entire visible region by appropriately choosing the composition of the sulfide host. Main application areas are flat panel displays based on thin film electroluminescence, field emission displays and ZnS-based powder electroluminescence for backlights. For these applications, special attention is given to BaAl2S4:Eu, ZnS:Mn and ZnS:Cu. Recently, sulfide materials have regained interest due to their ability (in contrast to oxide materials) to provide a broad band, Eu2+-based red emission for use as a color conversion material in white-light emitting diodes (LEDs). The potential application of rare-earth doped binary alkaline-earth sulfides, like CaS and SrS, thiogallates, thioaluminates and thiosilicates as conversion phosphors is discussed. Finally, this review concludes with the size-dependent luminescence in intrinsic colloidal quantum dots like PbS and CdS, and with the luminescence in doped nanoparticles.

A visible-light-excited europium(III) complex-based luminescent probe for visualizing copper ions and hydrogen sulfide in living cells

NASA Astrophysics Data System (ADS)

Wang, Yiren; Wang, Huan; Yang, Mei; Yuan, Jingli; Wu, Jing

2018-01-01

Development of visible-light-excited lanthanide (III) complex-based luminescent probes is highly appealing due to their superiority of less damage to the living biosystems over the conventional UV-light-excited ones. In this work, a visible-light-excited europium (III) complex-based luminescent probe, BPED-BHHCT-Eu3+-BPT, has been designed and synthesized by conjugating the Cu2+-binding N,N-bis(2-pyridylmethyl)ethanediamine (BPED) to a tetradentate β-diketone ligand 4,4‧-bis(1″,1″,1″,2″,2″,3″,3″-heptafluoro-4″,6″-hexanedione-6″-yl)chlorosulfo-o-terphenyl (BHHCT) and coordinating with a coligand 2-(N,N-diethylanilin-4-yl)-4,6-bis(pyrazol-1-yl)-1,3,5-triazine) (BPT) for the time-gated luminescence detection of Cu2+ ions and hydrogen sulfide (H2S) in living cells. BPED-BHHCT-Eu3+-BPT exhibited a sharp excitation peak at 407 nm and a wide excitation window extending to beyond 460 nm. Upon its reaction with Cu2+ ions, the luminescence of BPED-BHHCT-Eu3+-BPT was efficiently quenched, which could be reversibly restored by the addition of H2S due to the strong affinity between Cu2+ ions and H2S. The "on-off-on" type luminescence behavior of BPED-BHHCT-Eu3+-BPT towards Cu2+ ions and H2S enabled the sensing of the two species with high sensitivity and selectivity. The performances of BPED-BHHCT-Eu3+-BPT for visualizing intracellular Cu2+ ions and H2S were investigated, and the results have demonstrated the practical applicability of the probe for molecular imaging of cells.

Genital Chlamydia Prevalence in Europe and Non-European High Income Countries: Systematic Review and Meta-Analysis

PubMed Central

Redmond, Shelagh M.; Alexander-Kisslig, Karin; Woodhall, Sarah C.; van den Broek, Ingrid V. F.; van Bergen, Jan; Ward, Helen; Uusküla, Anneli; Herrmann, Björn; Andersen, Berit; Götz, Hannelore M.; Sfetcu, Otilia; Low, Nicola

2015-01-01

Background Accurate information about the prevalence of Chlamydia trachomatis is needed to assess national prevention and control measures. Methods We systematically reviewed population-based cross-sectional studies that estimated chlamydia prevalence in European Union/European Economic Area (EU/EEA) Member States and non-European high income countries from January 1990 to August 2012. We examined results in forest plots, explored heterogeneity using the I2 statistic, and conducted random effects meta-analysis if appropriate. Meta-regression was used to examine the relationship between study characteristics and chlamydia prevalence estimates. Results We included 25 population-based studies from 11 EU/EEA countries and 14 studies from five other high income countries. Four EU/EEA Member States reported on nationally representative surveys of sexually experienced adults aged 18–26 years (response rates 52–71%). In women, chlamydia point prevalence estimates ranged from 3.0–5.3%; the pooled average of these estimates was 3.6% (95% CI 2.4, 4.8, I2 0%). In men, estimates ranged from 2.4–7.3% (pooled average 3.5%; 95% CI 1.9, 5.2, I2 27%). Estimates in EU/EEA Member States were statistically consistent with those in other high income countries (I2 0% for women, 6% for men). There was statistical evidence of an association between survey response rate and estimated chlamydia prevalence; estimates were higher in surveys with lower response rates, (p = 0.003 in women, 0.018 in men). Conclusions Population-based surveys that estimate chlamydia prevalence are at risk of participation bias owing to low response rates. Estimates obtained in nationally representative samples of the general population of EU/EEA Member States are similar to estimates from other high income countries. PMID:25615574

Eu3+ functionalized Sc-MOFs: Turn-on fluorescent switch for ppb-level biomarker of plastic pollutant polystyrene in serum and urine and on-site detection by smartphone.

PubMed

Lian, Xiao; Miao, Tifang; Xu, Xiaoyu; Zhang, Chi; Yan, Bing

2017-11-15

The harm of plastic pollutants for human and environment is being paid more and more attention. Polystyrene (PS) and styrene are toxic compounds used in large quantities in the production of fiberglass reinforced polyesters. In this work, a simple method was designed for independent detecting polystyrene and styrene biomarker (phenylglyoxylic acid, PGA) in serum and urine. We prepared Eu3+ functionalized Sc-based metal-organic frameworks as turn-on fluorescent switch for PGA. The distinct enhanced luminescence is observed from the Eu@MOFs with addition of PGA. The fabricated fluorescent switch has several appealing features including high sensitivity (LOD = 4.16 ppb), quick response time (less than 5s) and broad linear range (0.02mg/mL to 0.5mg/mL). Furthermore, Eu@MOFs exhibits excellent selectivity that it is not affected by congeneric biomarkers. More interestingly, a paper-based probe has been devised. The paper-based fluorescence probe would perform an obvious fluorescence change from navy to red with the variety of PGA content. The practicability of the on-site detection platform for quantitative analysis using a colour scanning APP in smartphone has been also demonstrated by coupled with our proposed paper based fluorescence probe. This work first provides a fast, accurate and sensitive method for independent monitoring PS biomarker PGA, and the paper-based probe exhibit a new idea for design portable and easy to operate sensing devices combine with smartphone. Copyright © 2017 Elsevier B.V. All rights reserved.

Multimodal Theranostic Nanoformulations Permit Magnetic Resonance Bioimaging of Antiretroviral Drug Particle Tissue-Cell Biodistribution

PubMed Central

Kevadiya, Bhavesh D.; Woldstad, Christopher; Ottemann, Brendan M.; Dash, Prasanta; Sajja, Balasrinivasa R.; Lamberty, Benjamin; Morsey, Brenda; Kocher, Ted; Dutta, Rinku; Bade, Aditya N.; Liu, Yutong; Callen, Shannon E.; Fox, Howard S.; Byrareddy, Siddappa N.; McMillan, JoEllyn M.; Bronich, Tatiana K.; Edagwa, Benson J.; Boska, Michael D.; Gendelman, Howard E.

2018-01-01

RATIONALE: Long-acting slow effective release antiretroviral therapy (LASER ART) was developed to improve patient regimen adherence, prevent new infections, and facilitate drug delivery to human immunodeficiency virus cell and tissue reservoirs. In an effort to facilitate LASER ART development, “multimodal imaging theranostic nanoprobes” were created. These allow combined bioimaging, drug pharmacokinetics and tissue biodistribution tests in animal models. METHODS: Europium (Eu3+)- doped cobalt ferrite (CF) dolutegravir (DTG)- loaded (EuCF-DTG) nanoparticles were synthesized then fully characterized based on their size, shape and stability. These were then used as platforms for nanoformulated drug biodistribution. RESULTS: Folic acid (FA) decoration of EuCF-DTG (FA-EuCF-DTG) nanoparticles facilitated macrophage targeting and sped drug entry across cell barriers. Macrophage uptake was higher for FA-EuCF-DTG than EuCF-DTG nanoparticles with relaxivities of r2 = 546 mM-1s-1 and r2 = 564 mM-1s-1 in saline, and r2 = 850 mM-1s-1 and r2 = 876 mM-1s-1 in cells, respectively. The values were ten or more times higher than what was observed for ultrasmall superparamagnetic iron oxide particles (r2 = 31.15 mM-1s-1 in saline) using identical iron concentrations. Drug particles were detected in macrophage Rab compartments by dual fluorescence labeling. Replicate particles elicited sustained antiretroviral responses. After parenteral injection of FA-EuCF-DTG and EuCF-DTG into rats and rhesus macaques, drug, iron and cobalt levels, measured by LC-MS/MS, magnetic resonance imaging, and ICP-MS were coordinate. CONCLUSION: We posit that these theranostic nanoprobes can assess LASER ART drug delivery and be used as part of a precision nanomedicine therapeutic strategy. PMID:29290806

Optical characterization of the new nanocomposite SBMA/Eu(TTA)3(Ph3PO)2

NASA Astrophysics Data System (ADS)

Bordian, Olga; Verlan, Victor; Culeac, Ion; Iovu, Mihail; Zubareva, Vera; Nistor, Iurie

2015-02-01

We describe a new nanocomposite material based on the copolymer of styrene with butyl methacrylate (1:1) (SBMA), and coordinating compound of Europium(III) Eu(TTA)3(Ph3PO)2. The SBMA/Eu(TTA)3(Ph3PO)2 nanocomposite was prepared by a simple technology and can be obtained in the form of optical fibers, thin films and planar waveguides on various substrates with large area. Experimental results on optical transmission and photoluminescence spectroscopy are presented. The nanocomposite exhibits a strong photoluminescence emission in the range 560-750 nm, with the main photoluminescence band at 613 nm.

Molecular farming on the rise--GMO regulators still walking a tightrope.

PubMed

Spök, Armin

2007-02-01

Recent increases in EU commercial and academic activities in molecular farming, and the proximity to market-stage of the first plant-made pharmaceuticals, represent a call to action for EU regulators. Drawing on the North American debate on molecular farming, it will be argued that both the rationale and the risks of molecular farming will differ significantly from those of first generation GM crops. Based on these differences, the suitability of the existing regulatory frameworks, which were developed in response to the arrival of earlier products, is discussed, and specific options for adapting the already complex EU regulatory system to cater for molecular farming are examined.

European perspectives of food safety.

PubMed

Bánáti, Diána

2014-08-01

Food safety has been a growing concern among European Union (EU) citizens over the last decades. Despite the fact that food has never been safer, consumers are considerably uncertain and increasingly critical about the safety of their food. The introduction of new principles, such as the primary responsibility of producers, traceability, risk analysis, the separation of risk assessment and risk management provided a more transparent, science-based system in Europe, which can help to restore consumers' lost confidence. The present EU integrated approach to food safety 'from farm to fork' aims to assure a high level of food safety within the EU. © 2014 Society of Chemical Industry.

EUO-Based Multifunctional Heterostructures

DTIC Science & Technology

2015-06-06

magnetoresistance and the metal -insulator transition resistance ratios of doped EuO by interfacing this semiconductor with niobium; the observed effect is...general and may be applied to any metal /semiconductor interface where the semiconductor shows large Zeeman splitting under magnetic field, (2...understanding the changes in electronic structure and Fermi-surface reconstruction that occur as doped EuO progresses through the ferromagnetic metal

Observation of divergent La{sup 3+} ion dilute effect in two series of 3-D fluorescent lanthanide-MOFs-based molecular alloys RE{sub x}La{sub 1−x}–EBTC (RE{sup 3+}=Eu{sup 3+} or Tb{sup 3+}; EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-etracarboxylate)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhai, Lu; State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093; Zhang, Wen-Wei, E-mail: wwzhang@nju.edu.cn

The lanthanide metal-organic frameworks (MOFs) [Ln{sub 2}(EBTC){sub 1.5}(CH{sub 3}OH){sub 4}]·6H{sub 2}O are isostructural to each other, where EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate; Ln{sup 3+}=La{sup 3+}, Eu{sup 3+} and Tb{sup 3+}; and the corresponding MOF is abbreviated as Ln–EBTC. MOFs Eu–EBTC and Tb–EBTC emit intense red and green luminescence (visible by bare eyes), respectively. The molecular alloys of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC have been successfully prepared by mixing Eu{sup 3+}/Tb{sup 3+} and La{sup 3+} salts with the desired molar ratio in the starting material. Two series of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC molecular alloys are isomorphic to the parentmore » Ln–EBTC MOFs, while exhibit divergent La{sup 3+} ion diluting effect, namely, with increasing the relative amount of La{sup 3+}, the intensity of characteristic emission arising from Tb{sup 3+} ion monotonely increases in Tb{sub x}La{sub 1−x}–EBTC molecular alloys, whereas that of Eu{sup 3+} ion shows non-monotone decrease in Eu{sub x}La{sub 1−x}–EBTC molecular alloys. The possible origin is discussed for such a divergent behavior between Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC molecular alloys. - Graphical abstract: Two series of 3-D fluorescent lanthanide-MOFs-based molecular alloys RE{sub x}La{sub 1−x}–EBTC (RE{sup 3+}=Eu{sup 3+} or Tb{sup 3+}; EBTC{sup 4−}=1,1′-ethynebenzene-3,3′,5,5′-tetracarboxylate) have been successfully prepared by mixing Eu{sup 3+}/Tb{sup 3+} and La{sup 3+} salts with the desired molar ratio in the starting material and showed photoluminescence property with divergent La{sup 3+} ion dilute effect. - Highlights: • 3-D molecular alloys of Eu{sub x}La{sub 1−x}–EBTC and Tb{sub x}La{sub 1−x}–EBTC were prepared. • They are isomorphic to the parent Ln–EBTC MOFs. • They show photoluminescence property with divergent La{sup 3+} ion diluting effect. • The possible origin is discussed for such a divergent behavior.« less

Organosilylated complex [Eu(TTA)3(Bpy-Si)]: a bifunctional moiety for the engeneering of luminescent silica-based nanoparticles for bioimaging.

PubMed

Duarte, Adriana P; Mauline, Léïla; Gressier, Marie; Dexpert-Ghys, Jeannette; Roques, Christine; Caiut, José Maurício A; Deffune, Elenice; Maia, Danielle C G; Carlos, Iracilda Z; Ferreira, Antonio A P; Ribeiro, Sidney J L; Menu, Marie-Joëlle

2013-05-14

A new highly luminescent europium complex with the formula [Eu(TTA)3(Bpy-Si)], where TTA stands for the thenoyltrifluoroacetone, (C4H3S)COCH2COCF3, chelating ligand and Bpy-Si, Bpy-CH2NH(CH2)3Si(OEt)3, is an organosilyldipyridine ligand displaying a triethoxysilyl group as a grafting function has been synthesized and fully characterized. This bifunctional complex has been grafted onto the surface of dense silica nanoparticles (NPs) and on mesoporous silica microparticles as well. The covalent bonding of [Eu(TTA)3(Bpy-Si)] inside uniform Stöber silica nanoparticles was also achieved. The general methodology proposed could be applied to any silica matrix, allowed high grafting ratios that overcome chelate release and the tendency to agglomerate. Luminescent silica-based nanoparticles SiO2-[Eu(TTA)3(Bpy-Si)], with a diameter of 28 ± 2 nm, were successfully tested as a luminescent labels for the imaging of Pseudomonas aeruginosa biofilms. They were also functionalized by a specific monoclonal antibody and subsequently employed for the selective imaging of Escherichia coli bacteria.

Utilization of native oxygen in Eu(RE)-doped GaN for enabling device compatibility in optoelectronic applications

DOE PAGES

Mitchell, Brandon; Timmerman, D.; Poplawsky, Jonathan D.; ...

2016-01-04

The detrimental influence of oxygen on the performance and reliability of V/III nitride based devices is well known. However, the influence of oxygen on the nature of the incorporation of other co-dopants, such as rare earth ions, has been largely overlooked in GaN. Here, we report the first comprehensive study of the critical role that oxygen has on Eu in GaN, as well as atomic scale observation of diffusion and local concentration of both atoms in the crystal lattice. We find that oxygen plays an integral role in the location, stability, and local defect structure around the Eu ions thatmore » were doped into the GaN host. Although the availability of oxygen is essential for these properties, it renders the material incompatible with GaN-based devices. However, the utilization of the normally occurring oxygen in GaN is promoted through structural manipulation, reducing its concentration by 2 orders of magnitude, while maintaining both the material quality and the favorable optical properties of the Eu ions. Furthermore, these findings open the way for full integration of RE dopants for optoelectronic functionalities in the existing GaN platform.« less

Spin transistor based on pure nonlocal Andreev reflection in EuO-graphene/superconductor/EuO-graphene nanostructure

NASA Astrophysics Data System (ADS)

Ang, Yee Sin; Ang, Lay Kee; Zhang, Chao; Ma, Zhongshui

In graphene-magnetic-insulator hybrid structure such as graphene-Europium-oxide, proximity induced exchange interaction opens up a spin-dependent bandgap and spin splitting in the Dirac band. We show that such band topology allows pure crossed Andreev reflection to be generated exclusively without the parasitic local Andreev reflection and elastic cotunnelling over a wide range of bias and Fermi levels. We model the charge transport in an EuO-graphene/superconductor/EuO-graphene three-terminal device and found that the pure non-local conductance exhibits rapid on/off switching characteristic with a minimal subthreshold swing of ~ 20 mV. Non-local conductance oscillation is observed when the Fermi levels in the superconducting lead is varied. The oscillatory behavior is directly related to the quasiparticle propagation in the superconducting lead and hence can be used as a tool to probe the subgap quasiparticle mode in superconducting graphene. The non-local current is 100% spin-polarized and is highly tunable in our proposed device. This opens up the possibility of highly tunable graphene-based spin transistor that operates purely in the non-local transport regime.

Photoemission properties of Eu-doped Zr1- x Ce x O2 (x = 0-0.2) nanoparticles prepared by hydrothermal method

NASA Astrophysics Data System (ADS)

Ozawa, Masakuni; Matsumoto, Masashi; Hattori, Masatomo

2018-01-01

Photoluminescent Eu-doped ZrO2 and Zr1- x Ce x O2 (x = 0-0.2) nanoparticles were prepared by a hydrothermal method. X-ray diffraction and Raman spectra indicated the formation of tetragonal crystals of ZrO2 and its solid solutions with a grain size of less than 10 nm diameter after heat treatment at 400 °C. The photoemission spectra of Zr1- x Ce x O2:Eu3+ nanocrystalline samples showed the typical emission of Eu3+ ions assigned to 5D0 → 7F1 (590 nm) and 5D0 → 7F2 (610 nm) transitions and additional emissions of 5D0 → 7F J with higher J of 3-5. Increasing the CeO2 concentration reduced the emission intensity, and the emission peak shift was affected by a local lattice distortion, i.e., CeO2 concentration. The present study provided fundamental knowledge that is expected to enable the fabrication of ZrO2-based nanocrystal phosphor materials and a measure for controlling the emission peak shift and intensity in oxide fluorite-based phosphor.

Measuring employment precariousness in the European Working Conditions Survey: the social distribution in Europe.

PubMed

Puig-Barrachina, Vanessa; Vanroelen, Christophe; Vives, Alejandra; Martínez, José Miguel; Muntaner, Carles; Levecque, Katia; Benach, Joan; Louckx, Fred

2014-01-01

Precarious employment is becoming an increasingly important social determinant of health inequalities among workers. The way in which contemporary employment arrangements and their health consequences are addressed in empirical research is mostly based on the contract-related or employment instability dimension. A broader conceptual approach including various important characteristics of the degrading of employment conditions and relations is needed. The general objective of this paper is to empirically test a new multidimensional construct for measuring precarious employment in an existing database. Special focus is on the social distribution of precarious employment. A subsample of 21,415 participants in the EU-27 from the Fourth European Working Conditions Survey-2005 was analysed. A cross-sectional study of the social distribution of precarious employment was conducted through the analysis of proportional differences according to gender, social class and credentials for the European Union as a whole and within each country. The 8 dimensions of the employment precariousness construct were represented by 11 indicators. In general, women, workers without supervisory authority, those with fewer credentials, and those living in Eastern and Southern European countries suffer the highest levels of precarious employment. Exceptionally, men, workers with supervisory authority and those with the highest credentials suffer the highest levels of long working hours, schedule unpredictability and uncompensated flexible working times. This article offers the first validation for an innovative multidimensional conceptualisation of employment precariousness applied to the analysis of existing survey data, showing the unequal distribution of precarious employment across the European labour force. This set of indicators can be useful for monitoring precarious employment.

Cover of coastal vegetation as an indicator of eutrophication along environmental gradients.

PubMed

Wikström, Sofia A; Carstensen, Jacob; Blomqvist, Mats; Krause-Jensen, Dorte

2016-01-01

Coastal vegetation communities are important for primary production, biodiversity, coastal protection, carbon and nutrient cycling which, in combination with their sensitivity to eutrophication, render them potential indicators of environmental status for environmental policies like the EU Water and Marine Strategy Framework Directives. We evaluated one potential indicator for coastal vegetation, the cumulative cover at depths where the vegetation is light limited, by investigating its response to eutrophication along gradients in natural conditions. We used a large data set covering the Swedish coastline, spanning broad gradients in nutrient level, water clarity, seabed substrate, physical exposure and climate in addition to a salinity gradient from 0.5 to 30.5. Macroalgal cover increased significantly along gradients of declining nutrient concentration and increasing water clarity when we had accounted for diver effects, spatio-temporal sampling variability, salinity gradients, wave exposure and latitude. The developed empirical model explained 79% of the variation in algal cover across 130 areas. Based on this, we identified macroalgal cover as a promising indicator across the Baltic Sea, Kattegat and Skagerrak. A parallel analysis of soft-substrate macrophytes similarly identified significant increases in cover with decreasing concentrations of total nitrogen and increasing salinity, but the resulting empirical model explained only 52% of the variation in cover, probably due to the spatially more variable nature of soft-substrate vegetation. The identified general responses of vegetation cover to gradients of eutrophication across wide ranges in environmental settings may be useful for monitoring and management of marine vegetation in areas with strong environmental gradients.

Ramifications of codoping SrI2:Eu with isovalent and aliovalent impurities

NASA Astrophysics Data System (ADS)

Feng, Qingguo; Biswas, Koushik

2016-12-01

Eu2+ doped SrI2 is an important scintillator having applications in the field of radiation detection. Codoping techniques are often useful to improve the electronic response of such insulators. Using first-principles based approach, we report on the properties of SrI2:Eu and the influence of codoping with aliovalent (Na, Cs) and isovalent (Mg, Ca, Ba, and Sn) impurities. These codopants do not preferably bind with Eu and are expected to remain as isolated impurities in the SrI2 host. As isolated defects they display amphoteric behavior having, in most cases, significant ionization energies of the donor and acceptor levels. Furthermore, the acceptor states of Na, Cs, and Mg can bind with I-vacancy forming charge compensated donor-acceptor pairs. Such pairs may also bind additional holes or electrons similar to the isolated defects. Lack of deep-to-shallow behavior upon codoping and its ramifications will be discussed.

Combinatorial search for green and blue phosphors of high thermal stabilities under UV excitation based on the K(Sr1-x-y)PO4:Tb3+ xEu2+y system.

PubMed

Chan, Ting-Shan; Liu, Yao-Min; Liu, Ru-Shi

2008-01-01

The present investigation aims at the synthesis of KSr 1-x-y PO 4:Tb(3+) x Eu(2+) y phosphors using the combinatorial chemistry method. We have developed square-type arrays consisting of 121 compositions to investigate the optimum composition and luminescence properties of KSrPO 4 host matrix under 365 nm ultraviolet (UV) light. The optimized compositions of phosphors were found to be KSr 0.93PO 4:Tb(3+) 0.07 (green) and KSr 0.995PO 4:Eu(2+) 0.005 (blue). These phosphors showed good thermal luminescence stability better than commercially available YAG:Ce at temperature above 200 degrees C. The result indicates that the KSr 1-x-y PO 4:Tb(3+) x Eu (2+)y can be potentially useful as a UV radiation-converting phosphor for light-emitting diodes.

Chemiluminescence of the reaction system Ce(IV)-non-steroidal anti-inflammatory drugs containing europium(III) ions and its application to the determination of naproxen in pharmaceutical preparations and urine.

PubMed

Kaczmarek, Małgorzata

2011-11-01

The chemiluminescence (CL) of oxidation of non-steroidal anti-inflammatory drugs (NSAIDs) by Ce(IV) ions, was recorded in the presence and absence europium(III) ions, in solution of pH ~ 4 of solution. Kinetic curves and CL emission spectra of the all studied systems were discussed. CL of measurable intensity was observed in the Ce(IV)-NP-Eu(III) reaction system only in acidic solutions. The CL spectrum rcegistered for this system shows emission bands, typical of Eu(III) ions, with maximum at λ ~ 600 nm. The chemiluminescent method, based on Eu(III) emission in reaction system of NP-Ce(IV)-Eu(III) in acid solution was therefore used for the determination of naproxen in mixture of non-steroidal anti-inflammatory drugs.

Luminescent amine sensor based on europium(III) chelate.

PubMed

Petrochenkova, Nataliya V; Mirochnik, Anatolii G; Emelina, Tatyana B; Sergeev, Alexander A; Leonov, Andrei A; Voznesenskii, Sergey S

2018-07-05

The effect of methylamine vapor on luminescence of Eu(III) tris-benzoylacetonate (I) immobilized in thin-layer chromatography plates has been investigated. It has been revealed that interaction of I with analyte vapor results in increase of the intensity of Eu(III) luminescence. The mechanism of the effect of methylamine vapors on intensification of the Eu(III) luminescence has been suggested using the data of IR spectroscopy and quantum chemistry calculations. The mechanism of luminescence sensitization consists in bonding of an analyte molecule with a water molecule into the coordination sphere of Eu(III). As a result, the bond of a water molecule with the luminescence centre weakens, rigid structural fragment including europium ion, water and methylamine molecules forms. The presence of such fragment must naturally promote decrease of influence of OH-vibrations on luminescence of the complex I. Copyright © 2018 Elsevier B.V. All rights reserved.

Photofunctional Eu3+/Tb3+ hybrids through sulfoxide linkages: coordination bonds construction, characterization and luminescence.

PubMed

Guo, Lei; Yan, Bing; Liu, Jin-Liang

2011-05-14

New kinds of organic-inorganic hybrid materials consisting of rare earth (Eu(3+), Tb(3+)) complexes covalently bonded to a silica-based network have been obtained by a sol-gel approach. Three novel versatile molecular building blocks containing sulfoxide organic units have been synthesized by methylene modification reaction, which are used as the ligands of rare earth ions and also as siloxane network precursors. The obtained hybrids are characterized by chemical analysis and spectroscopic methods such as FTIR and UV; XRD and SEM. Photoluminescence measurements on the prepared hybrids were performed showing the intra-4f(n) emission in the visible (Eu(3+), Tb(3+)) region and in all the cases being sensitized by the sulfoxide ligands. The emission quantum efficiency and the Judd-Ofelt intensity parameters of Eu(3+) hybrid materials were also investigated in detail.

Sol–gel synthesis, structure and luminescence properties of Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} phosphors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, Yuntong; Liu, Xiaohua, E-mail: xhliuxhliu@tom.com

2015-04-15

Graphical abstract: The phosphor powders of Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} were prepared by sol–gel method. The dependence of luminescence intensity on the Eu{sup 3+} concentration was investigated. - Highlights: • We synthesize Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} phosphors by the sol–gel method. • The effect of temperature on the crystallinity and morphology is investigated. • The phosphor presents an intense CT band in near UV range (370–410 nm). • The concentration quenching mechanism is the exchange interaction. - Abstract: Double-perovskite Ba{sub 2}Zn{sub 1−x}MoO{sub 6}:xEu{sup 3+} (x = 0, 0.02, 0.04, 0.06, 0.08, 0.1) orange–red emitting phosphors were synthesized by using themore » sol–gel method. The crystalline structure and photoluminescence properties of the phosphors were investigated. The X-ray diffraction (XRD) patterns indicate that the structure of matrix Ba{sub 2}ZnMoO{sub 6} is cubic double-perovskite with space group Fm-3m. The Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} phosphors present an intense broad charge transfer (CT) band absorption in near UV range (370–410 nm), which attributes to the charge transfer state of MoO{sub 6}, and performs orange–red emission of Eu{sup 3+} ({sup 5}D{sub 0} → {sup 7}F{sub 1} transition) at around 596 nm. A low concentration quenching occurs in Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} and the optimal doping concentration is about 6 mol%. The Ba{sub 2}ZnMoO{sub 6}:Eu{sup 3+} phosphors are considered to be a promising orange–red emitting phosphor for near ultraviolet GaN-based white light emitting diode.« less

Macroscopic and Microscopic Investigation of U(VI) and Eu(III) Adsorption on Carbonaceous Nanofibers.

PubMed

Sun, Yubing; Wu, Zhen-Yu; Wang, Xiangxue; Ding, Congcong; Cheng, Wencai; Yu, Shu-Hong; Wang, Xiangke

2016-04-19

The adsorption mechanism of U(VI) and Eu(III) on carbonaceous nanofibers (CNFs) was investigated using batch, IR, XPS, XANES, and EXAFS techniques. The pH-dependent adsorption indicated that the adsorption of U(VI) on the CNFs was significantly higher than the adsorption of Eu(III) at pH < 7.0. The maximum adsorption capacity of the CNFs calculated from the Langmuir model at pH 4.5 and 298 K for U(VI) and Eu(III) were 125 and 91 mg/g, respectively. The CNFs displayed good recyclability and recoverability by regeneration experiments. Based on XPS and XANES analyses, the enrichment of U(VI) and Eu(III) was attributed to the abundant adsorption sites (e.g., -OH and -COOH groups) of the CNFs. IR analysis further demonstrated that -COOH groups were more responsible for U(VI) adsorption. In addition, the remarkable reducing agents of the R-CH2OH groups were responsible for the highly efficient adsorption of U(VI) on the CNFs. The adsorption mechanism of U(VI) on the CNFs at pH 4.5 was shifted from inner- to outer-sphere surface complexation with increasing initial concentration, whereas the surface (co)precipitate (i.e., schoepite) was observed at pH 7.0 by EXAFS spectra. The findings presented herein play an important role in the removal of radionuclides on inexpensive and available carbon-based nanoparticles in environmental cleanup applications.

Facile Atmospheric Pressure Synthesis of High Thermal Stability and Narrow-Band Red-Emitting SrLiAl3N4:Eu(2+) Phosphor for High Color Rendering Index White Light-Emitting Diodes.

PubMed

Zhang, Xuejie; Tsai, Yi-Ting; Wu, Shin-Mou; Lin, Yin-Chih; Lee, Jyh-Fu; Sheu, Hwo-Shuenn; Cheng, Bing-Ming; Liu, Ru-Shi

2016-08-03

Red phosphors (e.g., SrLiAl3N4:Eu(2+)) with high thermal stability and narrow-band properties are urgently explored to meet the next-generation high-power white light-emitting diodes (LEDs). However, to date, synthesis of such phosphors remains an arduous task. Herein, we report, for the first time, a facile method to synthesize SrLiAl3N4:Eu(2+) through Sr3N2, Li3N, Al, and EuN under atmospheric pressure. The as-synthesized narrow-band red-emitting phosphor exhibits excellent thermal stability, including small chromaticity shift and low thermal quenching. Intriguingly, the title phosphor shows an anomalous increase in theoretical lumen equivalent with the increase of temperature as a result of blue shift and band broadening of the emission band, which is crucial for high-power white LEDs. Utilizing the title phosphor, commercial YAG:Ce(3+), and InGaN-based blue LED chip, a proof-of-concept warm white LEDs with a color rendering index (CRI) of 91.1 and R9 = 68 is achieved. Therefore, our results highlight that this method, which is based on atmospheric pressure synthesis, may open a new means to explore narrow-band-emitting nitride phosphor. In addition, the underlying requirements to design Eu(2+)-doped narrow-band-emitting phosphors were also summarized.

Synthesis and Luminescence Properties of Rare Earth Activated Phosphors for near UV-Emitting LEDs for Efficacious Generation of White Light

NASA Astrophysics Data System (ADS)

Han, Jinkyu

Solid state white-emitting lighting devices based on LEDs outperform conventional light sources in terms of lifetime, durability, and luminous efficiency. Near UV-LEDs in combination with blue-, green-, and red-emitting phosphors show superior luminescence properties over the commercialized blue-emitting LED with yellow-emitting phosphors. However, phosphor development for near UV LEDs is a challenging problem and a vibrant area of research. In addition, using the proper synthesis technique is an important consideration in the development of phosphors. In this research, efficient blue-, green-yellow, red-emitting, and color tunable phosphors for near UV LEDs based white light are identified and prepared by various synthetic methods such as solid state reaction, sol-gel/Pechini, co-precipitation, hydrothermal, combustion and spray-pyrolysis. Blue-emittingLiCaPO4:Eu2+, Green/yellow-emitting (Ba,Sr)2SiO4:Eu2+, color tunable solid solutions of KSrPO4-(Ba,Ca)2SiO4:Eu 2+, and red-emitting (Ba,Sr,Ca)3MgSi2O 8:Eu2+,Mn2+ show excellent excitation profile in the near UV region, high quantum efficiency, and good thermal stability for use in solid state lighting applications. In addition, different synthesis methods are analyzed and compared, with the goal of obtaining ideal phosphors, which should have not only have high luminous output but also optimal particle size (˜150--400 nm) and spherical morphology. For Sr2SiO 4:Eu2+, the sol-gel method appears to be the best method. For Ba2SiO4:Eu2+, the co-precipitation method is be the best. Lastly, the fabrication of core/SiO2 shell particles alleviate surface defects and improve luminescence output and moisture stability of nano and micron sized phosphors. For nano-sized Y2O 3:Eu3+, Y2SiO5:Ce3+,Tb 3+, and (Ba,Sr)2SiO4, the luminescence emission intensity of the core/shell particles were significantly higher than that of bare cores. Additionally, the moisture stability is also improved by SiO 2 shells, the luminescence output of SiO2 coated green emitting Ca3SiO4Cl2:Eu2+ and blue emitting Ca2PO4Cl:Eu2+ phosphors is comparable to that of fresh phosphors although bare phosphors shows significant luminescence quenching after water exposure.

Optical spectroscopy of rare earth ion-doped TiO2 nanophosphors.

PubMed

Chen, Xueyuan; Luo, Wenqin

2010-03-01

Trivalent rare-earth (RE3+) ion-doped TiO2 nanophosphors belong to one kind of novel optical materials and have attracted increasing attention. The luminescence properties of different RE3+ ions in various TiO2 nanomaterials have been reviewed. Much attention is paid to our recent progresses on the luminescence properties of RE3+ (RE = Eu, Er, Sm, Nd) ions in anatase TiO2 nanoparticles prepared by a sol-gel-solvothermal method. Using Eu3+ as a sensitive optical probe, three significantly different luminescence centers of Eu3+ in TiO2 nanoparticles were detected by means of site-selective spectroscopy at 10 K. Based on the crystal-field (CF) splitting of Eu3+ at each site, C2v and D2 symmetries were proposed for Eu3+ incorporated at two lattice sites. A structural model for the formation of multiple sites was proposed based on the optical behaviors of Eu3+ at different sites. Similar multi-site luminescence was observed in Sm(3+)- or Nd(3+)-doped TiO2 nanoparticles. In Eu(3+)-doped TiO2 nanoparticles, only weak energy transfer from the TiO2 host to the Eu3+ ions was observed at 10 K due to the mismatch of energy between the TiO2 band-gap and the Eu3+ excited states. On the contrary, efficient host-sensitized luminescences were realized in Sm(3+)- or Nd(3+)-doped anatase TiO2 nanoparticles due to the match of energy between TiO2 band-gap and the Sm3+ and Nd3+ excited states. The excitation spectra of both Sm(3+)- and Nd(3+)-doped samples exhibit a dominant broad peak centered at approximately 340 nm, which is associated with the band-gap of TiO2, indicating that sensitized emission is much more efficient than direct excitation of the Sm3+ and Nd3+ ions. Single lattice site emission of Er3+ in TiO2 nanocrystals can be achieved by modifying the experimental conditions. Upon excitation by a Ti: sapphire laser at 978 nm, intense green upconverted luminescence was observed. The characteristic emission of Er3+ ions was obtained both in the ultraviolet-visible (UV-vis) and near-infrared regions through the high-resolution experiments at 10 K. The CF experienced by Er3+ in TiO2 nanocrystal was systematically studied by means of the energy level fitting.

Utilizing hyaluronic acid as a versatile platform for fluorescence resonance energy transfer-based glucose sensing.

PubMed

Ge, Minghao; Bai, Pengli; Chen, Mingli; Tian, Jingjing; Hu, Jun; Zhi, Xu; Yin, Huancai; Yin, Jian

2018-03-01

Here, we utilized the ultrasonic emulsification technique to generate hyaluronic acid microspheres incorporating a fluorescence-based glucose biosensor. We synthesized a novel lanthanide ion luminophore based on Eu 3+ . Eu sulfosuccinimidyl dextran (Eu-dextran) and Alexa Fluor 647 sulfosuccinimidyl-ConA (Alexa Fluor 647-ConA) were encapsulated in hyaluronic acid hydrogel to generate microspheres. Glucose sensing was carried out using a fluorescence resonance energy transfer (FRET)-based assay principle. A proportional fluorescence intensity increase was found within a 0.5-10-mM glucose concentration range. The glucose-sensing strategy showed an excellent tolerance for potential interferents. Meanwhile, the fluorescent signal of hyaluronic acid microspheres was very stable after testing for 72 h in glucose solution. Overall, hyaluronic acid microspheres encapsulating sensing biomolecules offer a stable and biocompatible biosensor for a variety of applications including cell culture systems, tissue engineering, detection of blood glucose, etc. Graphical abstract We report an ingenious biosensor encapsulated in hyaluronic acid microspheres for monitoring of glucose. Glucose sensing is carried out using a fluorescence resonance energy transfer-based assay principle with a novel lanthanide ions luminophore. The glucose detection system has excellent biocompatibility and stability for monitoring of glucose.

Photoluminescence of A- and B-site Eu{sup 3+}-substituted (Sr{sub x}Ba{sub 1−x}){sub 2}CaW{sub y}Mo{sub 1−y}O{sub 6} phosphors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sletnes, M.; Lindgren, M.; Valmalette, J.C.

The photoluminescence of two series of A- and B-site Eu{sup 3+} substituted (Sr{sub x}Ba{sub 1−x}){sub 2}CaW{sub y}Mo{sub 1−y}O{sub 6} double perovskite phosphor materials, (Sr{sub x}Ba{sub 1−x}){sub 1.96}Eu{sub 0.02}K{sub 0.02}CaW{sub y}Mo{sub 1−y}O{sub 6} and (Sr{sub x}Ba{sub 1−x}){sub 2}Ca{sub 0.96}Eu{sub 0.02}Li{sub 0.02}W{sub y}Mo{sub 1−y}O{sub 6} (x and y=0, 0.25, 0.50, 0.75, and 1), were studied systematically as a function of stoichiometry and crystal structure. The Eu{sup 3+} lattice sites controlled by co-doping with either K or Li were confirmed by Raman spectroscopy. The variation in integrated emission intensity and emission colour over the experimental matrix was examined using statistical tools, and themore » observed trends were rationalized based on the physical and electronic structure of the phosphors. Phosphors with Eu on B-site with maximum Sr content had remarkably higher emission intensities than all other materials, but the emission was more orange than red due to domination of the {sup 5}D{sub 0}–{sup 7}F{sub 1} (595 nm) transition of Eu{sup 3+}. The relative intensities of the {sup 5}D{sub 0}–{sup 7}F{sub 2} (615 nm) and {sup 5}D{sub 0}–{sup 7}F{sub 1} transitions of Eu{sup 3+}, and thus the red-shift of the emission, decreased linearly with increasing Sr content in the A-site Eu-substituted phosphors, and reached a maximum for Sr{sub 1.96}Eu{sub 0.02}K{sub 0.02}CaW{sub 0.25}Mo{sub 0.75}O{sub 6}. A maximum external quantum efficiency of 17% was obtained for the phosphor Sr{sub 2}Ca{sub 0.7}Eu{sub 0.15}Li{sub 0.15}W{sub 0.5}Mo{sub 0.5}O{sub 6} with Eu on B-site. - Highlights: • Systematic study of the photoluminescence of Eu{sup 3+}-doped (Sr{sub x}Ba{sub 1−x}){sub 2}CaW{sub y}Mo{sub 1−y}O{sub 6}. • The Eu{sup 3+} lattice sites were confirmed by Raman spectroscopy. • A large parameter space was investigated using statistical tools. • A maximum external QE of 17% was obtained for Sr{sub 2}Ca{sub 0.7}Eu{sub 0.15}Li{sub 0.15}W{sub 0.5}Mo{sub 0.5}O{sub 6}.« less

Enhancing photovoltaic performance of dye-sensitized solar cells by rare-earth doped oxide of SrAl{sub 2}O{sub 4}:Eu{sup 3+}

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Lijun; Guo, Weihua; Liaoning Provincial College Key Laboratory of New Materials and Material Modification, Dalian Polytechnic University, Dalian 116034

2016-04-15

Graphical abstract: Current–voltage characteristics of DSSCs based on the photoanodes doping different SrAl{sub 2}O{sub 4}:Eu{sup 3+} and doping 3% SrAl{sub 2}O{sub 4}. - Highlights: • A down-conversion (DC) nanocrystal (SrAl{sub 2}O{sub 4}:Eu{sup 3+}) was synthesized. • The effect of SrAl{sub 2}O{sub 4}:Eu{sup 3+} doped in photoanode in DSSCs was investigated. • SrAl{sub 2}O{sub 4}:Eu{sup 3+} doped in photoanode appeared the better photovoltaic performances. • The dual function of DC and p-type doping effect were explained. - Abstract: SrAl{sub 2}O{sub 4}:Eu{sup 3+} down-conversion (DC) nanocrystals were synthesized by a sol–gel method and then doped in TiO{sub 2} as a photoanode inmore » dye-sensitized solar cells (DSSCs). Differential thermal analysis, fourier transform infrared spectroscopy, X-ray diffraction and Brunauer–Emmet–Teller analysis confirmed the formation of SrAl{sub 2}O{sub 4}:Eu{sup 3+} nanocrystals with diameters of ∼47 nm, pore size of ∼25 nm, sintering temperature of 1300 °C. The photoluminescence and UV–vis absorption spectra of the SrAl{sub 2}O{sub 4}:Eu{sup 3+} revealed a DC from ultraviolet light to visible light which matched the strong absorbing region of the N719 dye. The photoelectric conversion efficiency of the DSSCs with a TiO{sub 2} photoanode doped with 3 wt% SrAl{sub 2}O{sub 4}:Eu{sup 3+} was 20% higher than that with a pure TiO{sub 2} photoanode. This phenomenon could be mainly explained by SrAl{sub 2}O{sub 4}:Eu{sup 3+} nanocrystals’ ability of DC and increased the short-circuit current density. It could be minorly due to the p-type doping effect and slightly improved the open-circuit voltage.« less

Multichannel Luminescence Properties of Mixed-Valent Eu2+/Eu3+ Coactivated SrAl3BO7 Nanocrystalline Phosphors for Near-UV LEDs.

PubMed

Liu, Xiaoming; Xie, Weijie; Lü, Ying; Feng, Jingchun; Tang, Xinghua; Lin, Jun; Dai, Yuhua; Xie, Yu; Yan, Liushui

2017-11-20

Up to now, orchestrating the coexistence of Eu 2+ and Eu 3+ activators in a single host lattice has been an extremely difficult task, especially for the appearance of the characteristic emission of Eu 2+ and Eu 3+ in order to generate white light. Nevertheless, here we demonstrate a new Eu 2+ /Eu 3+ coactivated SrAl 3 BO 7 nanocrystalline phosphor with abundant and excellent multichannel luminescence properties. A series of Eu 2+ /Eu 3+ coactivated SrAl 3 BO 7 nanocrystalline phosphors were prepared through a Pechini-type sol-gel method followed by a reduction process. With excitation of UV/NUV light, the prepared SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphors show not only the characteristic f-f transitions of Eu 3+ ion ( 5 D J → 7 F J,J' , J, J' = 0-3), but also the 5d → 4f transitions of Eu 2+ ion with comparable intensity from 400 to 700 nm in the whole visible spectral region. The luminescence color of the SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor can be tuned from blue, blue-green, white, and orange to orange-red by changing the excitation wavelength, the overall doping concentration of europium ions (Eu 2+ , Eu 3+ ), and the relative ratio of Eu 2+ to Eu 3+ ions to some extent. A single-phase white-light emission has been realized in SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor. The obtained SrAl 3 BO 7 :Eu 2+ ,Eu 3+ phosphor has potential application in the area of NUV white-light-emitting diodes.

Economic impacts of policies affecting crop biotechnology and trade.

PubMed

Anderson, Kym

2010-11-30

Agricultural biotechnologies, and especially transgenic crops, have the potential to boost food security in developing countries by offering higher incomes for farmers and lower priced and better quality food for consumers. That potential is being heavily compromised, however, because the European Union and some other countries have implemented strict regulatory systems to govern their production and consumption of genetically modified (GM) food and feed crops, and to prevent imports of foods and feedstuffs that do not meet these strict standards. This paper analyses empirically the potential economic effects of adopting transgenic crops in Asia and Sub-Saharan Africa. It does so using a multi-country, multi-product model of the global economy. The results suggest the economic welfare gains from crop biotechnology adoption are potentially very large, and that those benefits are diminished only very slightly by the presence of the European Union's restriction on imports of GM foods. That is, if developing countries retain bans on GM crop production in an attempt to maintain access to EU markets for non-GM products, the loss to their food consumers as well as to farmers in those developing countries is huge relative to the slight loss that could be incurred from not retaining EU market access. Copyright © 2010 Elsevier B.V. All rights reserved.

Matching Up to the Information Society: An Evaluation of the EU, the EU Accession Countries, Switzerland and the United States. Summary

ERIC Educational Resources Information Center

Graafland-Essers, Irma; Cremonini, Leon; Ettedgui, Emile; Botterman, Maarten

2003-01-01

This report presents the current understanding of the advancement of the Information Society within the European Union and countries that are up for accession in 2004, and is based on the SIBIS (Statistical Indicators Benchmarking the Information Society) surveys and analyses per SIBIS theme and country. The report is unique in its coherent and…

Matching Up to the Information Society: An Evaluation of the EU, the EU Accession Countries, Switzerland and the United States

ERIC Educational Resources Information Center

Graafland-Essers, Irma; Cremonini, Leon; Ettedgui, Emile; Botterman, Maarten

2003-01-01

This report presents the current understanding of the advancement of the Information Society within the European Union and countries that are up for accession in 2004, and is based on the SIBIS (Statistical Indicators Benchmarking the Information Society) surveys and analyses per SIBIS theme and country. The report is unique in its coherent and…

Making Higher Education More European through Student Mobility? Revisiting EU Initiatives in the Context of the Bologna Process

ERIC Educational Resources Information Center

Papatsiba, Vassiliki

2006-01-01

This paper focuses on the analysis of student mobility in the EU as a means to stimulate convergence of diverse higher education systems. The argument is based on official texts and other texts of political communication of the European Commission. The following discussion is placed within the current context of the Bologna process and its aim to…

Tunable-color luminescence via energy transfer in NaCa13/18Mg5/18PO4:A (A = Eu2+/Tb3+/Mn2+, Dy3+) phosphors for solid state lighting.

PubMed

Li, Kai; Fan, Jian; Mi, Xiaoyun; Zhang, Yang; Lian, Hongzhou; Shang, Mengmeng; Lin, Jun

2014-11-17

A series of NaCa13/18Mg5/18PO4(NCMPO):A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) phosphors have been prepared by the high-temperature solid-state reaction method. The X-ray diffraction (XRD) and Rietveld refinement, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), cathodoluminescence (CL), decay lifetimes, and PL quantum yields (QYs) were utilized to characterize the phosphors. The pure crystalline phase of as-prepared samples has been demonstrated via XRD measurement and Rietveld refinements. XPS reveals that the Eu(2+)/Tb(3+)/Mn(2+) can be efficiently doped into the crystal lattice. NCMPO:Eu(2+)/Tb(3+)/Mn(2+) phosphors can be effectively excited under UV radiation, which show tunable color from purple-blue to red including white emission based on energy transfer from Eu(2+) to Tb(3+)/Mn(2+) ions. Under low-voltage electron beam bombardment, the NCMPO:A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) display their, respectively, characteristic emissions with different colors, and the CL spectrum of NCMPO:0.04Tb(3+) has the comparable intensity to the ZnO:Zn commercial product. In addition, the calculated CIE coordinate of NCMPO:0.04Tb(3+) (0.252, 0.432) is more saturated than it (0.195, 0.417). These results reveal that NCMPO:A (A = Eu(2+)/Tb(3+)/Mn(2+), Dy(3+)) may be potential candidate phosphors for WLEDs and FEDs.

Eu3+-doped β-Ga2O3 nanophosphors: annealing effect, electronic structure and optical spectroscopy.

PubMed

Zhu, Haomiao; Li, Renfu; Luo, Wenqin; Chen, Xueyuan

2011-03-14

A comprehensive survey of electronic structure and optical properties of rare-earth ions-doped semiconductor is of vital importance for their potential applications. In this work, Eu(3+)-doped β-Ga(2)O(3) nanocrystals were synthesized via a combustion method. The evolution of the optical properties of nanophosphors with increasing the annealing temperature was investigated in detail by means of excitation and emission spectra at room temperature and 10 K. Eu(3+) ions were proved to be incorporated into the crystal lattice of the β-Ga(2)O(3) phase after annealing the as-prepared nanoparticles at 1100 °C. It was observed that the substitution of Eu(3+) for Ga(3+) occurred at merely single site, in spite of two crystallographically nonequivalent sites of Ga(3+) in β-Ga(2)O(3). Spectroscopic evidence corroborated and clarified the local symmetry of C(s) for Eu(3+) at this single site. From the high-resolution excitation and emission spectra, 71 crystal-field levels of Eu(3+) in β-Ga(2)O(3) were identified and analyzed in terms of 19 freely varied free-ions and crystal-field parameters based on C(s) symmetry. The standard deviation of the final fitting is as low as 12.9 cm(-1), indicating an excellent agreement between experimental and calculated energy levels. The temperature-dependent luminescence dynamics of the (5)D(0) multiplet for Eu(3+) in β-Ga(2)O(3) phosphors has also been revealed for the first time from 10 to 300 K.

Fabrication of Eu doped CdO [Al/Eu-nCdO/p-Si/Al] photodiodes by perfume atomizer based spray technique for opto-electronic applications

NASA Astrophysics Data System (ADS)

Ravikumar, M.; Ganesh, V.; Shkir, Mohd; Chandramohan, R.; Arun Kumar, K. Deva; Valanarasu, S.; Kathalingam, A.; AlFaify, S.

2018-05-01

In this study, thin films of cadmium oxide (CdO) with different concentrations (0, 1, 3, and 5 wt%) of Eu doping were deposited onto Si and glass substrates by a novel and facile spray technique using simple perfume atomizer for the first time. Prepared films were characterized for structural, morphological, optical properties and the photo diode studies, using X-ray diffraction, scanning electron microscope, UV-Vis spectrophotometer, Isbnd V characteristics, and fundamental parameters are reported. All the prepared Eu:CdO films exhibit cubic structure. The preferential orientation is along (200) plane. Scanning electron microscopy study indicates the growth of smooth and pin-hole free films with clusters of homogeneous grains. The values of band gap energy are found to be varying from 2.42 to 2.33 eV for various Eu doping concentration from 0 to 5 wt%. EDAX studies revealed the presence of Eu, Cd and O elements without any other impurities. FTIR spectra showed a peak at 575 cm-1 confirming the stretching mode of Cdsbnd O. The resistivity (ρ), high carrier concentration (n) and carrier mobility (μ) for 3 wt% CdO thin film are found to be 0.452 × 10-3(Ω.cm), 17.82 × 1020 cm-3 and 7.757 cm2/V, respectively. Current-voltage measurements on the fabricated nanostructured Al/Eu-nCdO/p-Si/Al heterojunction device showed a non-linear electric characteristics indicating diode like behaviour.

Two-dimensional high spatial-resolution dosimeter using europium doped potassium chloride: a feasibility study

NASA Astrophysics Data System (ADS)

Li, H. Harold; Driewer, Joseph P.; Han, Zhaohui; Low, Daniel A.; Yang, Deshan; Xiao, Zhiyan

2014-04-01

Recent research has shown that KCl:Eu2+ has great potential for use in megavoltage radiation therapy dosimetry because this material exhibits excellent storage performance and is reusable due to strong radiation hardness. This work reports the authors’ attempts to fabricate 2D KCl:Eu2+ storage phosphor films (SPFs) using both a physical vapor deposition (PVD) method and a tape casting method. X-ray diffraction analysis showed that a 10 µm thick PVD sample was composed of highly crystalline KCl. No additional phases were observed, suggesting that the europium activator had been completely incorporated into the KCl matrix. Photostimulated luminescence and photoluminescence spectra suggested that F (Cl-) centers were the electron storage centers post x-ray irradiation and that Eu2+ cations acted as luminescence centers in the photostimulation process. The 150 µm thick casted KCl:Eu2+ SPF showed sub-millimeter spatial-resolution. Monte Carlo simulations further demonstrated that the admixture of 20% KCl:Eu2+ and 80% low Z polymer binder exhibited almost no energy-dependence in a 6 MV beam. KCl:Eu2+ pellet samples showed a large dynamic range from 0.01 cGy to 60 Gy dose-to-water, and saturated at approximately 500 Gy as a result of KCl's intrinsic high radiation hardness. Taken together, this work provides strong evidence that KCl:Eu2+-based SPF with associated readout apparatus could result in a novel electronic film system that has all the desirable features associated with classic radiographic film and, importantly, water equivalence and the capability of permanent identification of each detector.

Enhanced adsorption of Eu(III) on mesoporous Al2O3/expanded graphite composites investigated by macroscopic and microscopic techniques.

PubMed

Sun, Yubing; Chen, Changlun; Tan, Xiaoli; Shao, Dadong; Li, Jiaxing; Zhao, Guixia; Yang, Shubin; Wang, Qi; Wang, Xiangke

2012-11-21

Mesoporous Al(2)O(3) was intercalated into an expanded graphite (EG) interlayer to prepare mesoporous Al(2)O(3)/EG composites. The basal spacing of mesoporous Al(2)O(3)/EG composites was enlarged as compared to raw graphite from the X-ray diffraction analysis. The massive surface functional groups and wedge-shaped pores were observed in terms of potentiometric acid-base titration analysis and scanning electron microscope, respectively. The pH-dependent adsorption of Eu(III) on mesoporous Al(2)O(3)/EG composites was evidently independent of ionic strength. The maximum adsorption capacity of Eu(III) on mesoporous Al(2)O(3)/EG composites at pH 6.0 and T = 293 K was calculated to be 5.14 mg g(-1). Desorption kinetics and cyclic operation results showed that mesoporous Al(2)O(3)/EG composites presented high hydrothermal stability in aqueous solution. The thermodynamic parameters suggested that Eu(III) adsorption on mesoporous Al(2)O(3)/EG composites is an endothermic and a spontaneous process. The decrease of Eu-O bond distance with the increasing pH demonstrated that the adsorption mechanism between Eu(III) and mesoporous Al(2)O(3)/EG composites would shift from outer-sphere surface complexation to inner-sphere surface complexation in terms of extended X-ray absorption fine structure spectroscopy analysis.

Optimization of Time-Resolved Fluorescence Assay for Detection of Eu-DOTA-labeled Ligand-Receptor Interactions

PubMed Central

De Silva, Channa R.; Vagner, Josef; Lynch, Ronald; Gillies, Robert J.; Hruby, Victor J.

2010-01-01

Lanthanide-based luminescent ligand binding assays are superior to traditional radiolabel assays due to improved sensitivity and affordability in high throughput screening while eliminating the use of radioactivity. Despite significant progress using lanthanide(III)-coordinated chelators such as DTPA derivatives, dissociation-enhanced lanthanide fluoroimmunoassays (DELFIA) have not yet been successfully used with more stable chelators, e.g. DOTA derivatives, due to the incomplete release of lanthanide(III) ions from the complex. Here, a modified and an optimized DELFIA procedure incorporating an acid treatment protocol is introduced for use with Eu(III)-DOTA labeled peptides. Complete release of Eu(III) ions from DOTA labeled ligands was observed using hydrochloric acid (2.0 M) prior to the luminescent enhancement step. NDP-α-MSH labeled with Eu(III)-DOTA was synthesized and the binding affinity to cells overexpressing the human melanocortin-4 receptors (hMC4R) was evaluated using the modified protocol. Binding data indicate that the Eu(III)-DOTA linked peptide bound to these cells with an affinity similar to its DTPA analogue. The modified DELFIA procedure was further used to monitor the binding of an Eu(III)-DOTA labeled heterobivalent peptide to the cells expressing both hMC4R and CCK-2 (Cholecystokinin) receptors. The modified assay provides superior results and is appropriate for high-throughput screening of ligand libraries. PMID:19852924

Fluorescent Silicon Nanorods-Based Ratiometric Sensors for Long-Term and Real-Time Measurements of Intracellular pH in Live Cells.

PubMed

Chu, Binbin; Song, Bin; Ji, Xiaoyuan; Su, Yuanyuan; Wang, Houyu; He, Yao

2017-11-21

Long-term and real-time investigation of the dynamic process of pH i changes is critically significant for understanding the related pathogenesis of diseases and the design of intracellular drug delivery systems. Herein, we present a one-step synthetic strategy to construct ratiometric pH sensors, which are made of europium (Eu)-doped one-dimensional silicon nanorods (Eu@SiNRs). The as-prepared Eu@SiNRs have distinct emission maxima peaks at 470 and 620 nm under 405 nm excitation. Of particular note, the fluorescence emission intensity at 470 nm decreases along with the increase of pH, while the one at 620 nm is nearly unaffected by pH changes, making Eu@SiNRs a feasible probe for pH sensing ratiometrically. Moreover, Eu@SiNRs are found to be responsive to a broad pH range (ca. 3-9), biocompatible (e.g., ∼100% of cell viability during 24 h treatment) and photostable (e.g., ∼10% loss of intensity after 40 min continuous UV irradiation). Taking advantages of these merits, we employ Eu@SiNRs for the visualization of the cytoplasmic alkalization process mediated by nigericin in living cells, for around 30 min without interruption, revealing important information for understanding the dynamic process of pH i fluctuations.

European Training and Research in Peritoneal Dialysis: scientific objectives, training, implementation and impact of the programme.

PubMed

Foster, Tom L; Ferrantelli, Evelina; van Wier-van der Schaaf, Tanja; Beelen, Robert H J

2014-03-01

Peritoneal dialysis (PD) offers many advantages over hospital-based haemodialysis, including better quality of life. Despite this, there is a general under-utilisation of PD in Europe, which, to some extent, can be attributed to a lack of knowledge and education amongst renal clinicians and nurses. The specific aim of the European Training and Research in Peritoneal Dialysis (EuTRiPD) programme is to address this lack of knowledge, to develop a minimum of five biomarkers that allow the prediction of outcome in PD and three therapeutic treatments to improve outcome in PD. EuTRiPD is a EU-wide consortium with clinical, academic and commercial partners set up to address this knowledge gap. By training through research and close collaboration between academic and commercial entities we hope to improve the outcome and uptake of PD. It is the goal of EuTRiPD to improve the currently hampered diagnostic therapeutic developments in renal replacement therapy (RRT) and structure existing high-quality PD-related research across Europe. It is hoped that EuTRiPD can and will have a significant impact on socio-economic and scientific aspects of PD. It is the aim for EuTRiPD to boost the uptake of PD throughout Europe by making PD the obvious choice for patients. © 2013 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Prevention of thermal- and moisture-induced degradation of the photoluminescence properties of the Sr2Si5N8:Eu(2+) red phosphor by thermal post-treatment in N2-H2.

PubMed

Zhang, Chenning; Uchikoshi, Tetsuo; Xie, Rong-Jun; Liu, Lihong; Cho, Yujin; Sakka, Yoshio; Hirosaki, Naoto; Sekiguchi, Takashi

2016-05-14

A red phosphor of Sr2Si5N8:Eu(2+) powder was synthesized by a solid state reaction. The synthesized phosphor was thermally post-treated in an inert and reductive N2-H2 mixed-gas atmosphere at 300-1200 °C. The main phase of the resultant phosphor was identified as Sr2Si5N8. A passivation layer of ∼0.2 μm thickness was formed around the phosphor surface via thermal treatment. Moreover, two different luminescence centers of Eu(SrI) and Eu(SrII) in the synthesized Sr2Si5N8:Eu(2+) phosphor were proposed to be responsible for 620 nm and 670 nm emissions, respectively. More interestingly, thermal- and moisture-induced degradation of PL intensity was effectively reduced by the formation of a passivation layer around the phosphor surface, that is, the relative PL intensity recovered 99.8% of the initial intensity even after encountering thermal degradation; both moisture-induced degraded external and internal QEs were merely 1% of the initial QEs. The formed surface layer was concluded to primarily prevent the Eu(2+) activator from being oxidized, based on the systemic analysis of the mechanisms of thermal- and moisture-induced degradation.

Development of Eu3+ activated monoclinic, perovskite, and garnet compounds in the Gd2O3-Al2O3 phase diagram as efficient red-emitting phosphors

NASA Astrophysics Data System (ADS)

Li, Jinkai; Li, Ji-Guang; Li, Jing; Liu, Shaohong; Li, Xiaodong; Sun, Xudong; Sakka, Yoshio

2013-10-01

Eu3+ doped Gd4Al2O9 (GdAM), GdAlO3 (GdAP), and Gd3Al5O12 (GdAG, containing 10 at% of Lu3+ for lattice stabilization) have been developed in this work as efficient red-emitting phosphors. With coprecipitated carbonate precursors, phase evolution studies found minimum processing temperatures of ~1000, 1100, and 1300 °C for the three phosphors to crystallize as pure phases, respectively. Compared with their yttrium aluminate counterparts, the gadolinium-based phosphors exhibit red-shifted O2--Eu3+ charge transfer excitation band (CTB) centers due to the lower electronegativity of Gd3+ and appreciably higher quantum yields of photoluminescence owing to the occurrence of efficient Gd3+→Eu3+energy transfer. The optimal Eu3+ contents were determined to be ~7.5 at% for GdAM and 5.0 at% for both GdAP and GdAG, and concentration quenching of luminescence was suggested to be due to exchange interactions. Fluorescence decay analysis found a shorter lifetime for the phosphor powder processed at a higher temperature or with a higher Eu3+ content, and the underlying mechanism was discussed. Fluorescence lifetimes were also compared between the yttrium and gadolinium phosphor systems for the dominant emissions.

Geostatistical enhancement of european hydrological predictions

NASA Astrophysics Data System (ADS)

Pugliese, Alessio; Castellarin, Attilio; Parajka, Juraj; Arheimer, Berit; Bagli, Stefano; Mazzoli, Paolo; Montanari, Alberto; Blöschl, Günter

2016-04-01

Geostatistical Enhancement of European Hydrological Prediction (GEEHP) is a research experiment developed within the EU funded SWITCH-ON project, which proposes to conduct comparative experiments in a virtual laboratory in order to share water-related information and tackle changes in the hydrosphere for operational needs (http://www.water-switch-on.eu). The main objective of GEEHP deals with the prediction of streamflow indices and signatures in ungauged basins at different spatial scales. In particular, among several possible hydrological signatures we focus in our experiment on the prediction of flow-duration curves (FDCs) along the stream-network, which has attracted an increasing scientific attention in the last decades due to the large number of practical and technical applications of the curves (e.g. hydropower potential estimation, riverine habitat suitability and ecological assessments, etc.). We apply a geostatistical procedure based on Top-kriging, which has been recently shown to be particularly reliable and easy-to-use regionalization approach, employing two different type of streamflow data: pan-European E-HYPE simulations (http://hypeweb.smhi.se/europehype) and observed daily streamflow series collected in two pilot study regions, i.e. Tyrol (merging data from Austrian and Italian stream gauging networks) and Sweden. The merger of the two study regions results in a rather large area (~450000 km2) and might be considered as a proxy for a pan-European application of the approach. In a first phase, we implement a bidirectional validation, i.e. E-HYPE catchments are set as training sites to predict FDCs at the same sites where observed data are available, and vice-versa. Such a validation procedure reveals (1) the usability of the proposed approach for predicting the FDCs over the entire river network of interest using alternatively observed data and E-HYPE simulations and (2) the accuracy of E-HYPE-based predictions of FDCs in ungauged sites. In a second phase, we develop a module, to be added to the flow-duration curve prediction framework, capable of enhancing E-HYPE-based predictions of FDCs by modelling the residuals obtained from the first phase. Among all possible methods, we apply geostatistical modelling of residuals and, alternatively, regional regression, so that residuals between empirical and E-HYPE-base predicted FDCs are described in terms of geomorphological and climatic catchment descriptors.

Occupational health legislation and practices related to seafarers on passenger ships focused on communicable diseases: results from a European cross-sectional study (EU SHIPSAN PROJECT)

PubMed Central

2010-01-01

Background Seafarers play an important role in the transmission of communicable diseases. The aim of the present study is to draw information and identify possible gaps on occupational health practices related to seafarers sailing on ships within the European Union Member States (EU MS) with focus on communicable diseases. Methods A structured questionnaire was sent to competent authorities from 21 EU MS. The questionnaire included questions about occupational health policies, medical certification of seafarers, communicable diseases reporting and relevant legislation. Descriptive analysis of the data was conducted by the use of Epi Info software: EU MS were categorized in four priority groups (A, B, C, D) based on: number of passenger ships visits, volume of passengers, and number of ports in each country. Moreover, EU MS were categorized to old and new, based on the date of entry in the EU. Results All 21 countries with relevant competent authorities responded to the questionnaire. The existence of specific national legislation/regulation/guidelines related to vaccination of seafarers was reported by three out of the 21 (14%) responding authorities. Surveillance data of communicable diseases related to seafarers are collected and analyzed by 4 (19%) authorities. Five out of 21 of the responding countries (24%) reported that tuberculin test result is required for the issuance of seafarer's medical certificate while a great variety of medical examination is required for the issuance of this certificate among countries. Gaps on occupational health services focused on communicable diseases related to maritime occupation have been reported by 33% of the responding countries. Responding authorities from Group A and B had the highest percentage of reported gaps followed by groups C and D. Old MS reported a higher frequency regarding gaps on occupational health services in comparison to new MS. Conclusion Our results revealed heterogeneity regarding occupational health of maritime employees in EU MS. This work provides some evidence that further work at international and European level could be considered, in order to explore the potential for harmonized initiatives regarding occupational health of seafarers. PMID:20181140

A System of Systems (SoS) Approach to transforming to a low carbon resource-efficient energy system: Insights for the European Union (EU)

NASA Astrophysics Data System (ADS)

Madani, K.; Jess, T.; Mahlooji, M.; Ristic, B.

2015-12-01

The world's energy sector is experiencing a serious transition from reliance on fossil fuel energy sources to extensive reliance on renewable energies. Europe is leading the way in this transition to a low carbon economy in an attempt to keep climate change below 2oC. Member States have committed themselves to reducing greenhouse gas emissions by 20% and increasing the share of renewables in the EU's energy mix to 20% by 2020. The EU has now gone a step further with the objective of reducing greenhouse gas emissions by 80-95% by 2050. Nevertheless, the short-term focus of the European Commission is at "cost-efficient ways" to cut its greenhouse gas emissions which forgoes the unintended impacts of a large expansion of low-carbon energy technologies on major natural resources such as water and land. This study uses the "System of Systems (SoS) Approach to Energy Sustainability Assessment" (Hadian and Madani, 2015) to evaluate the Relative Aggregate Footprint (RAF) of energy sources in different European Union (EU) member states. RAF reflects the overall resource-use efficiency of energy sources with respect to four criteria: carbon footprint, water footprint, land footprint, and economic cost. Weights are assigned to the four resource use efficiency criteria based on each member state's varying natural and economic resources to examine the changes in the desirability of energy sources based on regional resource availability conditions, and to help evaluating the overall resource use efficiency of the EU's energy portfolio. A longer-term strategy in Europe has been devised under the "Resource Efficient Europe" flagship imitative intended to put the EU on course to using resources in a sustainable way. This study will highlight the resource efficiency of the EU's energy sector in order to assist in a sustainable transition to a low carbon economy in Europe. ReferenceHadian S, Madani K (2015) A System of Systems Approach to Energy Sustainability Assessment: Are All Renewables Really Green? Ecological Indicators, 52, 194-206.

Control of Eu Luminescence Centers by Codoping of Mg and Si into Eu-Doped GaN

NASA Astrophysics Data System (ADS)

Lee, Dong-gun; Wakamatsu, Ryuta; Koizumi, Atsushi; Terai, Yoshikazu; Fujiwara, Yasufumi

2013-08-01

The effects of Mg and Si codoping on Eu luminescence properties have been investigated in Eu-doped GaN (GaN:Eu). The Mg codoping into GaN:Eu produced novel luminescence centers consisting of Eu and Mg, and increased photoluminescence (PL) intensity in Eu,Mg-codoped GaN (GaN:Eu,Mg). However, this increased PL intensity was quenched by thermal annealing in N2 ambient, which is due to activation of Mg acceptors. In GaN:Eu,Mg codoped additionally with Si (GaN:Eu,Mg,Si), on the other hand, the Eu-Mg centers disappeared, while an additional luminescence center appeared. Furthermore, the additional luminescence center showed no quenching under N2 annealing because Si donors compensated for the Mg acceptors in GaN. Thermal quenching of the luminescence center was also approximately half of that in GaN:Eu. These results indicate that the codoping with additional impurities in GaN:Eu is a powerful technique to control Eu luminescence centers for realization of improved device performance in red light-emitting diodes using GaN:Eu.

Controlled synthesis and novel photoluminescence properties of BaTiO{sub 3}:Eu{sup 3+}/Eu{sup 2+} nanocrystals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Feng, Li; Li, Ying; Wang, Guofeng, E-mail: wanggf75@gmail.com

2015-01-15

Highlights: • Tetragonal phase BaTiO{sub 3}:Eu nanocrystals were successfully synthesized using a hydrothermal method. • Under 398 nm excitation, the emissions from Eu{sup 2+} and Eu{sup 3+} ions were observed. • The emission band of Eu{sup 2+} from BaTiO{sub 3}:Eu was observed to broaden with increasing Eu concentration. - Abstract: Tetragonal phase BaTiO{sub 3}:Eu nanocrystals were successfully synthesized using a hydrothermal method and a subsequent calcination treatment. The structures and morphologies of nanocrystals were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and scanning electron microscopy. The photoluminescence properties of BaTiO{sub 3}:Eu were investigated in detail. Under 398 nmmore » excitation, the emissions from Eu{sup 2+} and Eu{sup 3+} ions were observed, indicating that Eu{sup 2+} and Eu{sup 3+} ions coexisted in BaTiO{sub 3}:Eu nanocrystals. Especially, the emission band of Eu{sup 2+} from BaTiO{sub 3}:Eu was observed to broaden with increasing Eu concentration. When the Eu concentration was 0.5 mol%, the {sup 5}D{sub 0} → {sup 7}F{sub 0} and {sup 5}D{sub 1} → {sup 7}F{sub 0} emissions were observed. In addition, under 537 nm excitation, the emission intensity increased with increasing Eu concentration.« less

A Strategy to enhance Eu3+ emission from LiYF4:Eu nanophosphors and green-to-orange multicolor tunable, transparent nanophosphor-polymer composites

PubMed Central

Kim, Su Yeon; Won, Yu-Ho; Jang, Ho Seong

2015-01-01

LiYF4:Eu nanophosphors with a single tetragonal phase are synthesized, and various strategies to enhance the Eu3+ emission from the nanophosphors are investigated. The optimized Eu3+ concentration is 35 mol%, and the red emission peaks due to the 5D0 →7FJ (J = 1 and 2) transitions of Eu3+ ions are further enhanced by energy transfer from a sensitizer pair of Ce3+ and Tb3+. The triple doping of Ce, Tb, and Eu into the LiYF4 host more effectively enhances the Eu3+ emission than the core/shell strategies of LiYF4:Eu(35%)/LiYF4:Ce(15%), Tb(15%) and LiYF4:Ce(15%), Tb(15%)/LiYF4:Eu(35%) architectures. Efficient energy transfer from Ce3+ to Eu3+ through Tb3+ results in three times higher Eu3+ emission intensity from LiYF4:Ce(15%), Tb(15%), Eu(1%) nanophosphors compared with LiYF4:Eu(35%), which contains the optimized Eu3+ concentration. Owing to the energy transfer of Ce3+ → Tb3+ and Ce3+ → Tb3+ → Eu3+, intense green and red emission peaks are observed from LiYF4:Ce(13%), Tb(14%), Eu(1-5%) (LiYF4:Ce, Tb, Eu) nanophosphors, and the intensity ratio of green to red emission is controlled by adjusting the Eu3+ concentration. With increasing Eu3+ concentration, the LiYF4:Ce, Tb, Eu nanophosphors exhibit multicolor emission from green to orange. In addition, the successful incorporation of LiYF4:Ce, Tb, Eu nanophosphors into polydimethylsiloxane (PDMS) facilitates the preparation of highly transparent nanophosphor-PDMS composites that present excellent multicolor tunability. PMID:25597900

Fabrication and characterization of thin-film phosphor combinatorial libraries

NASA Astrophysics Data System (ADS)

Mordkovich, V. Z.; Jin, Zhengwu; Yamada, Y.; Fukumura, T.; Kawasaki, M.; Koinuma, H.

2002-05-01

The laser molecular beam epitaxy method was employed to fabricate thin-film combinatorial libraries of ZnO-based phosphors on different substrates. Fabrication of both pixel libraries, on the example of Fe-doped ZnO, and spread libraries, on the example of Eu-doped ZnO, has been demonstrated. Screening of the Fe-doped ZnO libraries led to the discovery of weak green cathodoluminescence with the maximum efficiency at the Fe content of 0.58 mol %. Screening of the Eu-doped ZnO libraries led to the discovery of unusual reddish-violet cathodoluminescence which is observed in a broad range of Eu concentration. No photoluminescence was registered in either system.

Synthesis and Characterization of YVO4-Based Phosphor Doped with Eu3+ Ions for Display Devices

NASA Astrophysics Data System (ADS)

Thakur, Shashi; Gathania, Arvind K.

2015-10-01

YVO4:Eu nanophosphor has been synthesized by the sol-gel method. Samples were characterized by x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy, Fourier-transform infrared spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, photoluminescence, and Raman spectroscopy. The XRD profile confirms the tetragonal phase of the Eu3+-doped YVO4 nanophosphor. The efficiency of the prepared phosphor was analyzed by means of its emission spectral profile. We also observed rich red emission from the prepared phosphor on excitation by an ultraviolet source. The calculated Commission International de l'Éclairage coordinates reveal excellent color purity efficiency. Such luminescent powder is useful as red phosphor in display device applications.

Exceptional capability of nanosized CeO(2) materials to "dissolve" lanthanide oxides established by time-gated excitation and emission spectroscopy.

PubMed

Tiseanu, Carmen; Parvulescu, Vasile; Avram, Daniel; Cojocaru, Bogdan; Sanchez-Dominguez, Margarita

2014-05-28

The atomic scale homogeneity of Ce and Zr oxygen bonds represents the main reason for enhanced total oxygen storage capability of CeO2-ZrO2 (Ce/Zr = 1) as compared to that of CeO2. Here, we demonstrate that the addition of 10% Eu(3+) by wet impregnation on preformed nanosized CeO2-ZrO2 (Ce/Zr = 1) followed by calcination induces a remarkable homogeneity of 10% Eu(3+)-CeO2-ZrO2 solid solution. By use of time-resolved emission and excitation spectroscopies, the improvement of the nanoscale chemical and structural homogeneity of 10% Eu(3+)-CeO2-ZrO2 calcined at 1000 as compared to sample calcined at 750 °C is demonstrated. Based on the comparison of luminescence properties of 10% Eu(3+) impregnated on preformed nanosized CeO2-ZrO2 and CeO2, we also show that the presence of zirconium does not only preserve the ability of cerium oxide to "dissolve" lanthanide oxide, but also determines an important stabilization of defects (oxygen vacancies) generated upon Eu(3+) doping.

Tuberculosis control in big cities and urban risk groups in the European Union: a consensus statement.

PubMed

van Hest, N A; Aldridge, R W; de Vries, G; Sandgren, A; Hauer, B; Hayward, A; Arrazola de Oñate, W; Haas, W; Codecasa, L R; Caylà, J A; Story, A; Antoine, D; Gori, A; Quabeck, L; Jonsson, J; Wanlin, M; Orcau, Å; Rodes, A; Dedicoat, M; Antoun, F; van Deutekom, H; Keizer, St; Abubakar, I

2014-03-06

In low-incidence countries in the European Union (EU), tuberculosis (TB) is concentrated in big cities, especially among certain urban high-risk groups including immigrants from TB high-incidence countries, homeless people, and those with a history of drug and alcohol misuse. Elimination of TB in European big cities requires control measures focused on multiple layers of the urban population. The particular complexities of major EU metropolises, for example high population density and social structure, create specific opportunities for transmission, but also enable targeted TB control interventions, not efficient in the general population, to be effective or cost effective. Lessons can be learnt from across the EU and this consensus statement on TB control in big cities and urban risk groups was prepared by a working group representing various EU big cities, brought together on the initiative of the European Centre for Disease Prevention and Control. The consensus statement describes general and specific social, educational, operational, organisational, legal and monitoring TB control interventions in EU big cities, as well as providing recommendations for big city TB control, based upon a conceptual TB transmission and control model.

White long-lasting phosphorescence generation in a CaAl2Si2O8 : Eu2+, Mn2+, Dy3+ system through persistent energy transfer

NASA Astrophysics Data System (ADS)

Zhang, Jinsu; Chen, Baojiu; Sun, Jiashi; Li, Xiangping; Cheng, Lihong; Zhong, Haiyang

2012-08-01

Based on the persistent energy transfer principle, Mn2+ was introduced into a CaAl2Si2O8 : Eu2+/Dy3+ phosphor to achieve white long-lasting emissions. Eu2+, Mn2+ and Dy3+ tri-doped CaAl2Si2O8 phosphors with various Mn2+ concentrations were prepared via a solid-state reaction, and the crystal structure of the phosphors was identified by the x-ray diffraction technique. The luminescent properties of the Eu2+, Mn2+ and Dy3+ tri-doped CaAl2Si2O8 phosphors were studied. The energy transfer behaviour from Eu2+ to Mn2+ was analysed within the framework of Dexter theory. The physical mechanism of energy transfer was assigned to the electric dipole-quadrupole interaction. It was also demonstrated that the colour coordinates of the phosphors can be tuned from the blue region to the white region in the colour space. Furthermore, the afterglow decay and thermoluminescence curves were measured, indicating excellent phosphorescence properties of the current phosphors.

Fabrication, structure, and properties of Fe3O4@C encapsulated with YVO4:Eu3+ composites

NASA Astrophysics Data System (ADS)

Shi, Jianhui; Tong, Lizhu; Liu, Deming; Yang, Hua

2012-03-01

The use of carbon shells offers many advantages in surface coating or surface modification due to their surface with activated carboxyl and carbonyl groups. In this study, the Fe3O4@C@YVO4:Eu3+ composites were prepared through a simple sol-gel process. Reactive carbon interlayer was introduced as a key component, which separates lanthanide-based luminescent component from the magnetite, more importantly, it effectively prevent oxidation of the Fe3O4 core during the whole preparation process. The morphology, structure, magnetic, and luminescent properties of the composites were characterized by transmission electron microscopy (TEM), high-resolution TEM, X-ray diffraction, X-ray photoelectron spectra, VSM, and photoluminescent spectrophotometer. As a result, the Fe3O4@C/YVO4:Eu3+ composites with well-crystallized and core-shell structure were prepared and the YVO4:Eu3+ luminescent layer decorating the Fe3O4@C core-shell microspheres are about 10 nm. In addition, the Fe3O4@C@YVO4:Eu3+ composites have the excellent magnetic and luminescent properties, which allow them great potential for bioapplications such as magnetic bioseparation, magnetic resonance imaging, and drug/gene delivery.

Syntheses of Eu-Activated Alkaline Earth Fluoride MF2 (M=Ca, Sr) Nanoparticles

NASA Astrophysics Data System (ADS)

Hong, Byung-Chul; Kawano, Katsuyasu

2007-09-01

The Eu2+ ion-activated CaF2 and SrF2 nanoparticles were prepared by the sol-gel technique assisted with the trifluoro-acetic acid (TFA), and were evaluated by X-ray diffraction (XRD), photoluminescence (PL), photoluminescence excitation (PLE) measurements and atomic force microscopy (AFM) observation. A modified reducing method based on the thermal-carbon reducing atmosphere (TCRA) treatment using activated carbon was proposed to realize the effective reduction from Eu3+ to Eu2+ ions, in which the nanoparticles showed a strong and broad luminescence due to the parity allowed 4f7-4f65d1 transition. From the XRD results, it was found that the average particle size proportionally increased in the range of 15 to 120 nm and 10 to 100 nm for CaF2 and SrF2, respectively, with increasing sintering temperatures 300-700 °C. The surface images of nanoparticles obtained by the AFM revealed that the grains with high uniformity grew with increasing TCRA temperatures. It was confirmed that the reduced Eu2+ ions were homogeneously dispersed with the critical distance 16-17 Å in the fluoride nanoparticles from the concentration quenching results.

[The Balance of Care approach for the development of custom-fit health care services for people with dementia on the margins of care between home and nursing home: experiences with its application in Germany].

PubMed

Stephan, Astrid; Renom Guiteras, Anna; Juchems, Stefan; Meyer, Gabriele

2013-01-01

In Germany as in other countries of the European Union (EU), the majority of people with dementia are cared for by their informal caregivers at home. Across countries, however, there are considerable differences in the time to nursing home admission. The European research project RightTimePlaceCare intends to establish good practice recommendations for how to sustain the preferred living situation as long as possible. The Balance of Care approach was used to develop these recommendations, which combines empirical data, cost estimates and expert consensus, and thus implemented in a multinational context for the first time. In eight EU countries a survey was conducted among 2,014 people with dementia and their informal caregivers in nursing homes (n=1,223) or at home (n=791). Selected descriptive characteristics of the study participants were used for case type development. The case types were translated into 14 case vignettes, which were discussed by five to six expert panels (each consisting of three to four participants) per country. The experts (n=161) recommended the most suitable living place (at home or in a nursing home) and customised care packages for home care situations. Across all countries, the experts predominantly recommended care at home for four of the case types whose reference group of study participants actually lived in a nursing home. These case types represent a relevant part of the study population. In Germany, the experts judged the case vignettes as realistic but criticised that information relevant for proper decision making was missing. Expert group discussions always ended in consensus, and care at home was predominately recommended. The proposed care packages most often comprised standard care services, and hence appeared to be realistic and feasible. The development of country-specific recommendations is still ongoing. In order to assess economic feasibility, estimated costs of home care packages will be compared with costs of nursing home care. Further outcomes like the quality of life will be considered for good practice recommendation finding. Balance of Care supports the development of empirically based expert recommendations. The approach is widely applicable but seems to be particularly useful for the development of local custom-fit healthcare services. The clinical effectiveness, safety, and cost implications of the Balance of Care approach remain to be investigated in future studies. Copyright © 2013. Published by Elsevier GmbH.

Development and applicability of a ready-to-use PCR system for GMO screening.

PubMed

Rosa, Sabrina F; Gatto, Francesco; Angers-Loustau, Alexandre; Petrillo, Mauro; Kreysa, Joachim; Querci, Maddalena

2016-06-15

With the growing number of GMOs introduced to the market, testing laboratories have seen their workload increase significantly. Ready-to-use multi-target PCR-based detection systems, such as pre-spotted plates (PSP), reduce analysis time while increasing capacity. This paper describes the development and applicability to GMO testing of a screening strategy involving a PSP and its associated web-based Decision Support System. The screening PSP was developed to detect all GMOs authorized in the EU in one single PCR experiment, through the combination of 16 validated assays. The screening strategy was successfully challenged in a wide inter-laboratory study on real-life food/feed samples. The positive outcome of this study could result in the adoption of a PSP screening strategy across the EU; a step that would increase harmonization and quality of GMO testing in the EU. Furthermore, this system could represent a model for other official control areas where high-throughput DNA-based detection systems are needed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Bulk Superconductivity Induced by Se Substitution in BiCh2-Based Layered Compounds Eu0.5Ce0.5FBiS2-xSex

NASA Astrophysics Data System (ADS)

Goto, Yosuke; Sogabe, Ryota; Mizuguchi, Yoshikazu

2017-10-01

We report the effect of Se substitution on the crystal structure and superconductivity of BiCh2-based (Ch: S, Se) layered compounds Eu0.5Ce0.5FBiS2-xSex (x = 0-1). Crystal structure analysis showed that both lattice constants, a and c, increased with increasing x, which is different from the related La-doped system Eu0.5La0.5FBiS2-xSex. This is due to Se substitution at both in-plane and out-of-plane Ch sites in the present Ce-doped system. Zero resistivity was observed for x = 0.2-1 above 2 K. The superconducting properties of Eu0.5Ce0.5FBiS2-xSex were investigated by magnetic susceptibility measurement, and the highest superconducting transition temperature of 3.5 K was obtained for x = 0.6 with a large shielding volume fraction. The emergence of bulk superconductivity and metallic conductivity can be qualitatively described in terms of the increased in-plane chemical pressure effect. A magnetic anomaly below 8 K, probably because of the ferromagnetic order of the magnetic moment of Ce3+ ions, coexists with bulk superconductivity in the BiCh2 layer. Since the effect of Se substitution on the magnetic transition temperature is ignorable, we suggest that the coupling between the magnetic order at the (Eu,Ce)F layer and the superconductivity at the Bi(S,Se)2 layer is weak.

The United Kingdom: Issues for the United States

DTIC Science & Technology

2007-07-16

of its EU partners than to the United States. For example, like other EU member states, Britain places great emphasis on multilateral... the prospects for the future of the U.S.-UK partnership, especially in the unfolding Brown era. It also describes UK views on political, security...delivery systems for its nuclear warheads since 1963. During the Cold War, the UK served as a vital base for U.S.

Chemiluminescent Diagnostics of Free-Radical Processes in an Abiotic System and in Liver Cells in the Presence of Nanoparticles Based on Rare-Earth Elements nReVO4:Eu3+ (Re = Gd, Y, La) and CeO2

NASA Astrophysics Data System (ADS)

Averchenko, E. A.; Kavok, N. S.; Klochkov, V. K.; Malyukin, Yu. V.

2014-11-01

We have used luminol-dependent chemiluminescence with Fenton's reagent to study the effect of nanoparticles based on rare-earth elements of different sizes and shapes on free-radical processes in abiotic and biotic cell-free systems, and also in isolated cells in vitro. We have estimated the effects of rare-earth orthovanadate nanoparticles of spherical (GdYVO4:Eu3+, 1-2 nm), spindle-shaped (GdVO4:Eu3+, 25 ×8 nm), and rod-shaped (LaVO4:Eu3+, 57 × (6-8) nm) nanoparticles and spherical CeO2 nanoparticles (sizes 1-2 nm and 8-10 nm). We have shown that in contrast to the abiotic system, in which all types of nanoparticles exhibit antiradical activity, in the presence of biological material, extra-small spherical (1-2 nm) nanoparticles of both types exhibit pro-oxidant activity, and also enhance pro-oxidant induced oxidative stress (for the pro-oxidants hydrogen peroxide and tert-butyl hydroperoxide). The effect of rare-earth orthovanadate spindle and rod shaped nanoparticles in this system was neutral; a moderate antioxidant effect was exhibited by 8-10 nm CeO2 nanoparticles.

The emerging mental health strategy of the European Union: a multi-level work-in-progress.

PubMed

Kelly, Brendan D

2008-01-01

Policy-making in the European Union (EU) is a complex process that can appear impenetrable and opaque. This paper examines the ongoing process of mental health policy-making in the EU. In 2005, the Health and Consumer Protectorate Director-General of the European Commission published a Green Paper and launched a consultation process aimed at mental health service-users, advocates, providers, business, social services and governments. While there were varying levels of participation between member states, a range of trans-national, national and infra-national actors made contributions. Based on these consultations, a 'Consultative Platform' was created and made 10 recommendations centered on the principles of partnership; establishing policy competencies; integrating mental health into national policies; involving stakeholders; and protecting human rights. This ongoing process illustrates many features of EU policy-making: (a) the European Commission generates an initiative; (b) policy focuses on EU standardization, with member states remaining central actors in service-delivery; (c) policy focuses on social inclusion; (d) the European Commission coordinates diverse networks of actors; and (e) there is 'multi-level' involvement, with direct interaction between trans-national, national and infra-national actors. An enhanced focus on epidemiological data and 'evidence-based policy' would increase rigor and focus further attention on this relatively neglected policy area.

The Applicability of Behaviour Change in Intervention Programmes Targeted at Ending Female Genital Mutilation in the EU: Integrating Social Cognitive and Community Level Approaches

PubMed Central

Brown, Katherine; Barrett, Hazel

2013-01-01

With increased migration, female genital mutilation (FGM) also referred to as female circumcision or female genital cutting is no longer restricted to Africa, the Middle East, and Asia. The European Parliament estimates that up to half a million women living in the EU have been subjected to FGM, with a further 180,000 at risk. Aware of the limited success of campaigns addressing FGM, the World Health Organization recommended a behavioural change approach be implemented in order to end FGM. To date, however, little progress has been made in adopting a behaviour change approach in strategies aimed at ending FGM. Based on research undertaken as part of the EU's Daphne III programme, which researched FGM intervention programmes linked to African communities in the EU (REPLACE), this paper argues that behaviour change has not been implemented due to a lack of understanding relating to the application of the two broad categories of behaviour change approach: individualistic decision-theoretic and community-change game-theoretic approaches, and how they may be integrated to aid our understanding and the development of future intervention strategies. We therefore discuss how these can be integrated and implemented using community-based participatory action research methods with affected communities. PMID:23983698

Elimination of trachoma as a public health problem in Ghana: Providing evidence through a pre-validation survey.

PubMed

Debrah, Oscar; Mensah, Ernest O; Senyonjo, Laura; de Souza, Dziedzom K; Hervie, Tei E; Agyemang, David; Bakajika, Didier; Marfo, Benjamin; Ahorsu, Felix; Wanye, Seth; Bailey, Robin; Koroma, Joseph B; Aboe, Agatha; Biritwum, Nana-Kwadwo

2017-12-01

In order to achieve elimination of trachoma, a country needs to demonstrate that the elimination prevalence thresholds have been achieved and then sustained for at least a two-year period. Ghana achieved the thresholds in 2008, and since 2011 has been implementing its trachoma surveillance strategy, which includes community and school screening for signs of follicular trachoma and trichiasis, in trachoma-endemic districts. In 2015-2016, the country conducted a district level population-based survey to validate elimination of trachoma as a public health problem. As per WHO recommendations, a cross-sectional survey, employing a two-stage cluster random sampling methodology, was used across 18 previously trachoma endemic districts (evaluation units (EUs) in the Upper West and Northern Regions of Ghana. In each EU 24 villages were selected based on probability proportional to estimated size. A minimum of 40 households were targeted per village and all eligible residents were examined for clinical signs of trachoma, using the WHO simplified grading system. The number of trichiasis cases unknown to the health system was determined. Household environmental risk factors for trachoma were also assessed. Data from 45,660 individuals were examined from 11,099 households across 18 EUs, with 27,398 (60.0%) children aged 1-9 years and 16,610 (36.4%) individuals 15 years and above All EUs had shown to have maintained the WHO elimination threshold for Trachomatous inflammation-Follicular (TF) (<5.0% prevalence) in children aged 1-9 years old. The EU TF prevalence in children aged 1-9 years old ranged from between 0.09% to 1.20%. Only one EU (Yendi 0.36%; 95% CI: 0.0-1.01) failed to meet the WHO TT elimination threshold (< 0.2% prevalence in adults aged 15 and above). The EU prevalence of trichiasis (TT) unknown to the health system in adults aged ≥15 years, ranged from 0.00% to 0.36%. In this EU, the estimated TT backlog is 417 All TT patients identified in the study, as well as through on-going surveillance efforts will require further management. A total of 75.9% (95% CI 72.1-79.3, EU range 29.1-92.6) of households defecated in the open but many households had access to an improved water source 75.9% (95%CI: 71.5-79.8, EU range 47.4-90.1%), with 45.5% (95% CI 41.5-49.7%, EU range 28.4-61.8%) making a round trip of water collection < 30 minutes. The findings from this survey indicate elimination thresholds have been maintained in Ghana in 17 of the 18 surveyed EUs. Only one EU, Yendi, did not achieve the TT elimination threshold. A scheduled house-by-house TT case search in this EU coupled with surgery to clear the backlog of cases is necessary in order for Ghana to request validation of elimination of trachoma as a public health problem.

A European perspective on intravascular catheter-related infections: report on the microbiology workload, aetiology and antimicrobial susceptibility (ESGNI-005 Study).

PubMed

Bouza, E; San Juan, R; Muñoz, P; Pascau, J; Voss, A; Desco, M

2004-09-01

The laboratory workload, microbiological techniques and aetiology of catheter-related infections in European hospitals are mostly unknown. The present study (ESGNI-005) comprised a 1-day (22 October 2001), laboratory-based, point-prevalence survey based on a questionnaire completed by microbiology laboratories in European (European Union (EU) and non-EU) hospitals. Also included were questions requesting retrospective information for the year 2000. In total, 151 hospitals from 26 European countries participated, of which 78.1% were teaching institutions. Overall, the estimated population served by these institutions was 121,363,800, and the estimated number of admissions during 2000 was 6,712,050. The total number of catheter tips processed during 2000 was 142,727, or 21/1,000 admissions, of which 23.7% were considered to be positive in the institutions using semiquantitative or quantitative techniques. Overall, EU centres received significantly more catheter tip samples/1,000 admissions and had a significantly higher rate of 'positivity' (p < 0.0001) than non-EU centres. Of the institutions surveyed, 11.4% (7.2% in EU countries and 23.7% in non-EU countries; p 0.04) used only qualitative techniques for catheter tip sample processing. On the day of the study, 167 microorganisms were recovered from significant catheter tip cultures (122 patients), of which Gram-positive bacteria represented 70.7%, Gram-negative bacteria 22.2%, and yeasts 7.2%. The five most common microorganisms were coagulase-negative staphylococci, Staphylococcus aureus, Candida spp., Enterococcus spp. and Pseudomonas spp. Overall, 19% of catheter tip cultures were polymicrobial. In the case of S. aureus, 40% of isolates were resistant to oxacillin, as were 63.4% of coagulase-negative staphylococcus isolates. Of 37 Gram-negative isolates, 35% were resistant to cefotaxime, 31% to ceftazidime, and 27% to ciprofloxacin. Imipenem and cefepime had the lowest reported rates of resistance (11%).

Scientific evaluation of an intra-curricular educational kit to foster inquiry-based learning (IBL)

NASA Astrophysics Data System (ADS)

Debaes, Nathalie; Cords, Nina; Prasad, Amrita; Fischer, Robert; Euler, Manfred; Thienpont, Hugo

2014-07-01

Society becomes increasingly dependent on photonics technologies; however there is an alarming lack of technological awareness among secondary school students. They associate photonics with experiments and components in the class room that seem to bear little relevance to their daily life. The Rocard Report [5] highlights the need for fostering students' scientific skills and technological awareness and identifies inquiry based learning (IBL) as a means to achieve this. Students need to actively do science rather than be silent spectators. The `Photonics Explorer' kit was developed as an EU funded project to equip teachers, free-of-charge, with educational material designed to excite, engage and educate European secondary school students using guided inquiry based learning techniques. Students put together their own experiments using up-to-date versatile components, critically interpret results and relate the conclusions to relevant applications in their daily life. They work hands-on with the material, thus developing and honing their scientific and analytical skills that are otherwise latent in a typical class room situation. A qualitative and quantitative study of the impact of the kit in the classroom was undertaken with 50 kits tested in 7 EU countries with over 1500 students in the local language. This paper reports on the results of the EU wide field tests that show the positive impact of the kit in raising the self-efficacy, scientific skills and interest in science among students and the effectiveness of the kit in implementing IBL strategies in classrooms across EU.

Nature-Based Solutions in the EU: Innovating with nature to address social, economic and environmental challenges.

PubMed

Faivre, Nicolas; Fritz, Marco; Freitas, Tiago; de Boissezon, Birgit; Vandewoestijne, Sofie

2017-11-01

Contemporary societies are facing a broad range of challenges, from pressures on human health and well-being to natural capital depletion, and the security of food, water and energy. These challenges are deeply intertwined with global processes, such as climate change and with local events such as natural disasters. The EU's research & innovation (R&I) policy is now seeking to address these challenges from a new perspective, with Nature-Based Solutions, and turn them into innovation opportunities that optimise the synergies between nature, society and the economy. Nature-Based Solutions can be an opportunity for innovation, and are here promoted by both policymakers and practitioners as a cost-effective way of creating a greener, more sustainable, and more competitive economy. Since 2013, the European Commission has devoted particular attention to Nature-Based Solutions through consultations and dialogues that sought to make the concept of these solutions more concrete and to define the concept's place within the spectrum of ecosystem-based approaches. In 2014, the Commission launched an expert group, which conducted further analysis, and made recommendations to help increase the use of Nature-Based Solutions and bring nature back into cities. In 2015, a survey was conducted on citizens' views and perceptions of 'Nature in Cities' to provide further insight for future work. Based on these elements and on results from running EU projects, the Commission has developed an R&I agenda for Nature-Based Solutions and has published targeted calls for proposals for large-scale demonstration projects in this field in 2016 and 2017. Additional R&I actions at EU level that promote systemic Nature-Based Solutions and their benefits to cities and territories are planned with the aim to improve the implementation capacity and evidence base for deploying Nature-Based Solutions and developing corresponding future markets. They are also expected to foster an interdisciplinary R&I and stakeholder community and the exchange of good practices in this field, as well as help shaping and implementing international R&I agendas on Nature-Based Solutions. Copyright © 2017. Published by Elsevier Inc.

Preparation, characterization and application of EVA film containing Eu3+ complex with 1-tridecanecarboxylic acid ligand

NASA Astrophysics Data System (ADS)

Dong, Jin; Lin, Baoping

2017-11-01

In this study, on the basis of complex Eu(DBM)3Phen which was widely applied in polymer matrices, quaternary complex Eu(DBM)2Phen(TA) was synthesized by the introduction of 1-tridecanecarboxylic acid (TA). XRD analyses show that Eu(DBM)2Phen(TA) inclines to amorphization compared with Eu(DBM)3Phen which is crystal. Ethylene-vinyl acetate (EVA) film doped with Eu(DBM)2Phen(TA) was prepared by casting method. SEM and AFM analyses show that the compatibility of Eu(DBM)2Phen(TA) with EVA is better than that of Eu(DBM)3Phen with EVA. Under the same addition amount of Eu3+ complexes, visible light transmittance of Eu(DBM)2Phen(TA)/EVA film is obviously greater than that of Eu(DBM)3Phen/EVA film, and the fluorescence intensity of Eu(DBM)2Phen(TA)/EVA film is only slightly lower than that of Eu(DBM)3Phen/EVA film. With the optimum addition amount of Eu3+ complexes, the energy conversion efficiency of the polycrystalline silicon solar cell coated with Eu(DBM)2Phen(TA)/EVA film is improved to 12.14%, and in comparison, that of the solar cell coated with Eu(DBM)3Phen/EVA film is only 11.98%. Hence Eu(DBM)2Phen(TA)/EVA film has a potential prospect as luminescent down-shifting material.

Bulk Superconductivity Induced by In-Plane Chemical Pressure Effect in Eu0.5La0.5FBiS2-xSex

NASA Astrophysics Data System (ADS)

Jinno, Gen; Jha, Rajveer; Yamada, Akira; Higashinaka, Ryuji; Matsuda, Tatsuma D.; Aoki, Yuji; Nagao, Masanori; Miura, Osuke; Mizuguchi, Yoshikazu

2016-12-01

We have investigated the Se substitution effect on the superconductivity of optimally doped BiS2-based superconductor Eu0.5La0.5FBiS2. Eu0.5La0.5FBiS2-xSex samples with x = 0-1 were synthesized. With increasing x, in-plane chemical pressure is enhanced. For x ≥ 0.6, superconducting transitions with a large shielding volume fraction are observed in magnetic susceptibility measurements, and the highest Tc is 3.8 K for x = 0.8. From low-temperature electrical resistivity measurements, a zero-resistivity state is observed for all the samples, and the highest Tc is observed for x = 0.8. With increasing Se concentration, the characteristic electrical resistivity changes from semiconducting-like to metallic, suggesting that the emergence of bulk superconductivity is linked with the enhanced metallicity. A superconductivity phase diagram of the Eu0.5La0.5FBiS2-xSex superconductor is established.

Pb{sub 1–x}Eu{sub x}Te alloys (0 ⩽ x ⩽ 1) as materials for vertical-cavity surface-emitting lasers in the mid-infrared spectral range of 4–5 μm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pashkeev, D. A., E-mail: d.pashkeev@gmail.com; Selivanov, Yu. G.; Chizhevskii, E. G.

2016-02-15

The optical properties of epitaxial layers and heterostructures based on Pb{sub 1–x}Eu{sub x}Te alloys (0 ⩽ x ⩽ 1) are analyzed in the context of designing Bragg mirrors and vertical-cavity surface-emitting lasers for the midinfrared spectral range. It is shown that the optimal heteropair for laser microcavities is Pb{sub 1–x}Eu{sub x}Te(x ≈ 0.06)/EuTe. On the basis of this heteropair, highly reflective Bragg mirrors consisting of just three periods and featuring a reflectance of R ⩾ 99.8% at the center of the stop band are grown by molecular-beam epitaxy on BaF{sub 2} (111) substrates. Single-mode optically pumped vertical-cavity surface-emitting lasers formore » the 4–5 μm spectral range operating at liquid-nitrogen temperatures are demonstrated.« less

Luminescence properties of Eu 3+ and Sm 3+ coactivated Gd(III) tungstate phosphor for light-emitting diodes

NASA Astrophysics Data System (ADS)

Wei, Qiong; Chen, Donghua

2009-09-01

Rare-earth ions coactivated red phosphors Gd 0.2RE 1.8(WO 4) 3 (RE=Eu 3+ and Sm 3+) were synthesized by conventional solid-state reaction using boric acid as a flux agent. The samples were characterized by X-ray diffractometer (XRD), energy-dispersive X-ray spectrometer (EDS) and luminescence spectrometer (LS). The results showed that the Eu-Sm system exhibits higher emission intensity than those of the Eu single-doped system and Sm separate-doped system under ultraviolet (UV) radiation. Samarium(III) ions are effective in broadening and strengthened absorptions around 400 nm. Furthermore, it exhibits enhanced luminescence emission. when the mole ratio of boric acid is about 0.16, the luminescence capability is optimum. Two strongest lines at ultraviolet (394 nm) and blue (465 nm) in excitation spectra of these phosphors match well with the output wavelengths of UV and blue GaN-based light-emitting diodes (LEDs) chips.

[Accidents and injuries in the EU. Results of the EuroSafe Reports].

PubMed

Bauer, R; Steiner, M; Kisser, R; Macey, S M; Thayer, D

2014-06-01

Accidents and injuries are a relevant although largely preventable public health problem. Information on the causes of accidents is the basis for accident prevention and product safety. The current report "Injuries in the European Union", edited by EuroSafe, the European Association for Injury Prevention and Safety Promotion, is a summary of key statistics on accidents and injuries at the EU level. In addition to international data on cause of death, the data of the European Injury Data Base (IDB) in particular are presented. The IDB is a unique data source for the EU based on an internationally standardized dataset of external causes and circumstances of injuries, which is collected in the emergency department of hospitals. Thus, the IDB covers the entire spectrum of accidents and injuries in sufficient detail as is necessary for the derivation of preventive measures and the knowledge of involved products. The currently available IDB data are collected by the participating Member States (2012: Austria, Cyprus, Denmark, Germany, Italy, Latvia, Malta, The Netherlands, Norway, Portugal, Slovenia, and Sweden) in self-interest (i.e., without legal obligation) with the support of the EU health programs. The central database for the IDB is run by the European Commission and provides public access to the aggregated data of the participating countries. Currently, over 100 IDB hospitals in the EU upload around 300,000 cases per year into the EU database. The IDB contains information on all accident sectors (transport, workplace, school etc.) with a focus on leisure and sports accidents. Depending on the accident sector, up to 25 variables (activities, products involved, means of transport etc.) and often also short narratives are recorded for each case. The report shows that 40 million people are treated in a hospital annually in the EU after accidents and violence, and that about 233,000 people die as a consequence of injury. There are large differences between countries in the rates of fatal and nonfatal injuries; these differences can be interpreted as a measure of the potential for prevention and as an indication of targeted measures in the countries with higher accident rates. The report also includes snapshots of the eight priority themes for injury prevention, as defined in the Recommendation of the European Council on Injury Prevention and Safety Promotion in 2007: children, adolescents and older people, vulnerable road users, sports, the use of products and services, violence, and self-injury. The implementation of the IDB has proven to be feasible and useful for the participating countries, especially for data-based accident prevention in the important areas of home, leisure, and sports accidents. In the framework of the EU project JAMIE (2011-2014, Joint Action for Injury Monitoring in Europe), the IDB partners are currently working on further improving the IDB standards and quality criteria as well as the recruitment of further IDB countries. The medium-term goal is to integrate the EU IDB in the Eurostat Statistical System and to put the collection of IDB data on a statutory footing.

EUGENE'HOM: A generic similarity-based gene finder using multiple homologous sequences.

PubMed

Foissac, Sylvain; Bardou, Philippe; Moisan, Annick; Cros, Marie-Josée; Schiex, Thomas

2003-07-01

EUGENE'HOM is a gene prediction software for eukaryotic organisms based on comparative analysis. EUGENE'HOM is able to take into account multiple homologous sequences from more or less closely related organisms. It integrates the results of TBLASTX analysis, splice site and start codon prediction and a robust coding/non-coding probabilistic model which allows EUGENE'HOM to handle sequences from a variety of organisms. The current target of EUGENE'HOM is plant sequences. The EUGENE'HOM web site is available at http://genopole.toulouse.inra.fr/bioinfo/eugene/EuGeneHom/cgi-bin/EuGeneHom.pl.

Education and training initiatives for crisis management in the European Union: a web-based analysis of available programs.

PubMed

Ingrassia, Pier Luigi; Foletti, Marco; Djalali, Ahmadreza; Scarone, Piercarlo; Ragazzoni, Luca; Corte, Francesco Della; Kaptan, Kubilay; Lupescu, Olivera; Arculeo, Chris; von Arnim, Gotz; Friedl, Tom; Ashkenazi, Michael; Heselmann, Deike; Hreckovski, Boris; Khorram-Manesh, Amir; Khorrram-Manesh, Amir; Komadina, Radko; Lechner, Kostanze; Patru, Cristina; Burkle, Frederick M; Fisher, Philipp

2014-04-01

Education and training are key elements of disaster management. Despite national and international educational programs in disaster management, there is no standardized curriculum available to guide the European Union (EU) member states. European- based Disaster Training Curriculum (DITAC), a multiple university-based project financially supported by the EU, is charged with developing a holistic and highly-structured curriculum and courses for responders and crisis managers at a strategic and tactical level. The purpose of this study is to qualitatively assess the prevailing preferences and characteristics of disaster management educational and training initiatives (ETIs) at a postgraduate level that currently exist in the EU countries. An Internet-based qualitative search was conducted in 2012 to identify and analyze the current training programs in disaster management. The course characteristics were evaluated for curriculum, teaching methods, modality of delivery, target groups, and funding. The literature search identified 140 ETIs, the majority (78%) located in United Kingdom, France, and Germany. Master level degrees were the primary certificates granted to graduates. Face-to-face education was the most common teaching method (84%). Approximately 80% of the training initiatives offered multi- and cross-disciplinary disaster management content. A competency-based approach to curriculum content was present in 61% of the programs. Emergency responders at the tactical level were the main target group. Almost all programs were self-funded. Although ETIs currently exist, they are not broadly available in all 27 EU countries. Also, the curricula do not cover all key elements of disaster management in a standardized and competency-based structure. This study has identified the need to develop a standardized competency-based educational and training program for all European countries that will ensure the practice and policies that meet both the standards of care and the broader expectations for professionalization of the disaster and crisis workforce.

Tunable blue-green emission and energy transfer properties in β-Ca3(PO4)2:Eu(2+), Tb(3+) phosphors with high quantum efficiencies for UV-LEDs.

PubMed

Li, Kai; Zhang, Yang; Li, Xuejiao; Shang, Mengmeng; Lian, Hongzhou; Lin, Jun

2015-03-14

A series of Eu(2+) and Tb(3+) singly-doped and co-doped β-Ca3(PO4)2 phosphors have been synthesized via the high-temperature solid-state reaction method. Thermogravimetric (TG) analysis, fourier transform infrared (FT-IR) spectra, X-ray diffraction (XRD) patterns and Rietveld refinements, photoluminescence (PL) spectra including temperature-dependent PL and quantum efficiency, and fluorescence decay lifetimes have been used to characterise the as-prepared samples. Under UV excitation, β-Ca3(PO4)2:Eu(2+) presents a broad emission band centered at 415 nm, which can be decomposed into five symmetrical bands peaking at 390, 408, 421, 435 and 511 nm based on the substitution of five kinds of Ca(2+) sites by Eu(2+) ions. β-Ca3(PO4)2:Tb(3+) shows characteristic emission lines under Tb(3+) 4f-5d transition excitation around 223 nm. In β-Ca3(PO4)2:Eu(2+), Tb(3+) phosphors, similar excitation spectra monitored at 415 and 547 nm have been observed, which illustrates the possibility of energy transfer from Eu(2+) to Tb(3+) ions. The variations in the emission spectra and decay lifetimes further demonstrate the existence of energy transfer from Eu(2+) to Tb(3+) ions under UV excitation. The energy transfer mechanism has been confirmed to be dipole-quadrupole, which can be validated via the agreement of critical distances obtained from the concentration quenching (12.11 Å) and spectrum overlap methods (9.9-13.2 Å). The best quantum efficiency can reach 90% for the β-Ca3(PO4)2:0.01Eu(2+), 0.15Tb(3+) sample under 280 nm excitation. These results show that the developed phosphors may possess potential applications in UV-pumped white light-emitting diodes.

Efficacy and safety of vi-tetanus toxoid conjugated typhoid vaccine (PedaTyph™) in Indian children: School based cluster randomized study.

PubMed

Mitra, Monjori; Shah, Nitin; Ghosh, Apurba; Chatterjee, Suparna; Kaur, Iqbal; Bhattacharya, Nisha; Basu, Suparna

2016-04-02

Vi polysaccharide typhoid vaccines cannot be used in children <2 years owing to poor immunogenic and T cell independent properties. Conjugate vaccine prepared by binding Vi to tetanus toxoids (Vi-TT) induces protective levels even in children <2 years. We evaluated efficacy and safety following vaccination with a Vi-TT vaccine in children 6 months to 12 years of age. Overall, 1765 subjects were recruited from two registered municipal urban slums of southern Kolkata. Most of the children of the slum dwellers attended the schools in the locality which was selected with permission from the school authority. Schools were randomly divided into vaccinated (Test group) and unvaccinated group (Control group). Children and their siblings of test group received 2-doses of PedaTyph™ vaccine at 6 weeks interval. Control group received vaccines as per national guidelines. Adverse events (AEs) were examined after 30 minutes, 1 month and clinical events were observed till 12 months post-vaccination. Incidence of culture positive typhoid fever in the control group was 1.27% vis-a-vis none in vaccine group during 12 months. In subgroup evaluated for immunogenicity, an antibody titer value of 1.8 EU/ml (95% CI: 1.5 EU/ml, 2.2 EU/ml), 32 EU/ml (95% CI: 27.0 EU/ml, 39.0 EU/ml) and 14 EU/ml (95% CI: 12.0 EU/ml, 17.0 EU/ml) at baseline, 6 weeks and 12 months, respectively was observed. Sero-conversion among the sub-group was 100% after 6 weeks of post-vaccination and 83% after 12 months considering 4-fold rise from baseline. The efficacy of vaccine was 100 % (95% CI: 97.6%, 100%) in the first year of follow-up with minimal AEs post vaccination. Vi conjugate typhoid vaccine conferred 100% protection against typhoid fever in 1765 children 6 months to 12 years of age with high immunogenicity in a subgroup from the vaccine arm.

Homogeneous time-resolved fluoroimmunoassay of microcystin-LR using layered WS2 nanosheets as a transducer

NASA Astrophysics Data System (ADS)

Qin, Xiaodan; Wang, Yuanxiu; Song, Bo; Wang, Xin; Ma, Hua; Yuan, Jingli

2017-06-01

A homogeneous time-resolved fluoroimmunoassay method for rapid and sensitive detection of microcystin-LR (MC-LR) in water samples was developed based on the interaction between water-soluble WS2 nanosheets and the conjugate of MC-LR with a luminescent Eu3+ complex BHHBCB-Eu3+ (BHHBCB: 1,2-bis[4‧-(1″,1″,1″,2″,2″,3″,3″-heptafluoro-4″,6″-hexanedion-6″-yl)- benzyl]-4-chlorosulfobenzene). The large lateral dimensions and high surface areas of two-dimensional layered WS2 nanosheets enable easy adsorption of the MC-LR-BHHBCB-Eu3+ conjugate, that lead to efficient quenching of the luminescence of Eu3+ complex via energy transfer or electron transfer process. However, the addition of monoclonal anti-MC-LR antibody can induce the formation of MC-LR-BHHBCB-Eu3+/antibody immune complex, which prevents the interaction between WS2 nanosheets and MC-LR-BHHBCB-Eu3+ to result in the restoration of Eu3+ luminescence. This signal transduction mechanism made it possible for analysis of the target MC-LR in a homogeneous system. The present method has advantages of rapidity and simplicity since the B/F (bound reagent/free reagent) separation steps, the solid-phase carrier and antibody labeling or modification process are not necessary. The proposed immunosensing system displayed a wide linear range, good precision and accuracy, and comparable sensitivity with a detection limit of 0.3 μg l-1, which satisfied the World Health Organization (WHO) provisional guideline limit of 1.0 μg l-1 for MC-LR in drinking water.

Effect of ambient oxygen on the photoluminescence of sol-gel-derived nanocrystalline ZrO2:Eu,Nb

NASA Astrophysics Data System (ADS)

Puust, Laurits; Kiisk, Valter; Eltermann, Marko; Mändar, Hugo; Saar, Rando; Lange, Sven; Sildos, Ilmo; Dolgov, Leonid; Matisen, Leonard; Jaaniso, Raivo

2017-06-01

The development of inorganic nanophosphors is an active research field due to many applications, including optical gas sensing materials. We found a systematic dependence of the photoluminescence (PL) of europium (Eu3+) impurity ions in zirconia (ZrO2) nanocrystals on the ambient oxygen concentration in a O2/N2 mixture at normal pressure. Europium-doped ZrO2 powders were synthesized via a sol-gel route. Heat-treatment at 1200 °C resulted in a well-developed monoclinic phase (XRD crystallite size of ~50 nm) and an intense PL of Eu3+ ions residing in the dominant phase (Eu3+ was excited directly at 395 or 464 nm). Co-doping with niobium resulted in a narrowing of the PL emission lines. Only Nb5+ was detected by XPS and is believed to charge-compensate Eu3+ activators throughout the material leading to a more regular crystal lattice. At room temperature, the exposure to oxygen suppressed the Eu3+ fluorescence, whereas, at elevated temperatures (300 °C), the effect was reversed. At 300 °C and under a focused continuous laser beam, a substantial PL response (>50%) was achieved when switching 100% of N2 for 100% of O2. PL decay kinetics clearly showed that at 300 °C fluorescence quenching centers were induced within the material by oxygen desorption. The relatively fast (<5 min) and sub-linear PL response to the changes of oxygen concentration shows that ZrO2:Eu,Nb is a promising PL-based oxygen sensing material over a wide-range of oxygen pressures.

Data-driven discovery of energy materials: efficient BaM2Si3O10 : Eu2+ (M = Sc, Lu) phosphors for application in solid state white lighting.

PubMed

Brgoch, Jakoah; Hasz, Kathryn; Denault, Kristin A; Borg, Christopher K H; Mikhailovsky, Alexander A; Seshadri, Ram

2014-01-01

In developing phosphors for application in solid state lighting, it is advantageous to target structures from databases with highly condensed polyhedral networks that produce rigid host compounds. Rigidity limits channels for non-radiative decay that will decrease the luminescence quantum yield. BaM(2)Si(3)O(10) (M = Sc, Lu) follows this design criterion and is studied here as an efficient Eu(2+)-based phosphor. M = Sc(3+) and Lu(3+) compounds with Eu(2+) substitution were prepared and characterized using synchrotron X-ray powder diffraction and photoluminescence spectroscopy. Substitution with Eu(2+) according to Ba(1-x)Eu(x)Sc(2)Si(3)O(10) and Ba(1-x)Eu(x)Lu(2)Si(3)O(10) results in UV-to-blue and UV-to-blue-green phosphors, respectively. Interestingly, substitution with Eu(2+) in the Lu(3+) containing material produces two emission peaks at low temperature and with 365 nm excitation, as allowed by the two substitution sites. The photoluminescence of the Sc(3+) compound is robust at high temperature, decreasing by only 25% of its room temperature intensity at 503 K, while the Lu-analogue suffers a large drop (75%) from its room temperature intensity. The decrease in emission intensity is explained as stemming from charge transfer quenching due to the short distances separating the luminescent centers on the Lu(3+) substitution site. The correlation between structure and optical response in these two compounds indicates that even though the structures are three-dimensionally connected, high symmetry is required to prevent structural distortions that could impact photoluminescence.

Two-dimensional high spatial-resolution dosimeter using europium doped potassium chloride: a feasibility study.

PubMed

Li, H Harold; Driewer, Joseph P; Han, Zhaohui; Low, Daniel A; Yang, Deshan; Xiao, Zhiyan

2014-04-21

Recent research has shown that KCl:Eu²⁺ has great potential for use in megavoltage radiation therapy dosimetry because this material exhibits excellent storage performance and is reusable due to strong radiation hardness. This work reports the authors' attempts to fabricate 2D KCl:Eu²⁺ storage phosphor films (SPFs) using both a physical vapor deposition (PVD) method and a tape casting method. X-ray diffraction analysis showed that a 10 µm thick PVD sample was composed of highly crystalline KCl. No additional phases were observed, suggesting that the europium activator had been completely incorporated into the KCl matrix. Photostimulated luminescence and photoluminescence spectra suggested that F (Cl(-)) centers were the electron storage centers post x-ray irradiation and that Eu²⁺ cations acted as luminescence centers in the photostimulation process. The 150 µm thick casted KCl:Eu²⁺ SPF showed sub-millimeter spatial-resolution. Monte Carlo simulations further demonstrated that the admixture of 20% KCl:Eu²⁺ and 80% low Z polymer binder exhibited almost no energy-dependence in a 6 MV beam. KCl:Eu²⁺ pellet samples showed a large dynamic range from 0.01 cGy to 60 Gy dose-to-water, and saturated at approximately 500 Gy as a result of KCl's intrinsic high radiation hardness. Taken together, this work provides strong evidence that KCl:Eu²⁺-based SPF with associated readout apparatus could result in a novel electronic film system that has all the desirable features associated with classic radiographic film and, importantly, water equivalence and the capability of permanent identification of each detector.

EuCARD2: enhanced accelerator research and development in Europe

NASA Astrophysics Data System (ADS)

Romaniuk, Ryszard S.

2013-10-01

Accelerator science and technology is one of a key enablers of the developments in the particle physic, photon physics and also applications in medicine and industry. EuCARD2 is an European research project which will be realized during 2013-2017 inside the EC FP7 framework. The project concerns the development and coordination of European Accelerator Research and Development. The project is particularly important, to a number of domestic laboratories, due to some plans to build large accelerator infrastructure in Poland. Large accelerator infrastructure of fundamental and applied research character stimulates around it the development and industrial applications as well as biomedical of advanced accelerators, material research and engineering, cryo-technology, mechatronics, robotics, and in particular electronics - like networked measurement and control systems, sensors, computer systems, automation and control systems. The paper presents a digest of the European project EuCARD2 which is Enhanced European Coordination for Accelerator Research and Development. The paper presents a digest of the research results and assumptions in the domain of accelerator science and technology in Europe, shown during the final fourth annual meeting of the EuCARD - European Coordination of Accelerator R&D, and the kick-off meeting of the EuCARD2. There are debated a few basic groups of accelerator systems components like: measurement - control networks of large geometrical extent, multichannel systems for large amounts of metrological data acquisition, precision photonic networks of reference time, frequency and phase distribution, high field magnets, superconducting cavities, novel beam collimators, etc. The paper bases on the following materials: Internet and Intranet documents combined with EuCARD2, Description of Work FP7 EuCARD-2 DoW-312453, 2013-02-13, and discussions and preparatory materials worked on by Eucard-2 initiators.

Electronic States in EuCu2(Ge1-xSix)2 Based on the Doniach Phase Diagram

NASA Astrophysics Data System (ADS)

Iha, Wataru; Yara, Tomoyuki; Ashitomi, Yousuke; Kakihana, Masashi; Takeuchi, Tetsuya; Honda, Fuminori; Nakamura, Ai; Aoki, Dai; Gouchi, Jun; Uwatoko, Yoshiya; Kida, Takanori; Tahara, Time; Hagiwara, Masayuki; Haga, Yoshinori; Hedo, Masato; Nakama, Takao; Ōnuki, Yoshichika

2018-06-01

We succeeded in growing single crystals of EuCu2(Ge1-xSix)2 (x = 0-1) by the Bridgman method using a Mo crucible and measured the electrical resistivity, specific heat, magnetic susceptibility, and magnetization, together with the electrical resistivity under pressure. EuCu2(Ge1-xSix)2 compounds follow the Doniach phase diagram as a function of the x content. Namely, EuCu2(Ge1-xSix)2 compounds exhibit antiferromagnetic ordering at a Néel temperature of TN = 15 K in EuCu2Ge2 (x = 0), a maximum of TN ≃ 20 K at x ≃ 0.5, TN → 0 at x ≃ 0.7, and a moderate heavy-fermion state at x = 0.8 and 1 (EuCu2Si2). The present result is reasonably consistent with the previous studies carried out using arc-melted polycrystal samples. A similar change in the electronic states was also found to be realized under pressure P for x = 0, 0.45, and 0.6. The Néel temperature of TN = 15 K for x = 0 (EuCu2Ge2) increases slightly as a function of pressure, at a rate of dTN/dP = 3.0 K/GPa, reaches a maximum of TN = 27 K at around 5-6 GPa, decreases steeply, and becomes zero at a critical pressure of Pc ≃ 7 GPa. A moderate heavy-fermion state is realized at 8 GPa. Similar results were also obtained for x = 0.45 and 0.6, with smaller critical pressures of Pc ≃ 4.5 and 2 GPa, respectively.

Understanding the complexation of Eu3+ with potential ligands used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle: A luminescence investigation.

PubMed

Sengupta, Arijit; Kadam, R M

2017-02-15

A systematic photoluminescence based investigation was carried out to understand the complexation of Eu 3+ with different ligands (TBP: tri-n-butyl phosphate, DHOA: di-n-hexyl octanamide, Cyanex 923: tri-n-alkyl phosphine oxide and Cyanex 272: Bis (2,4,4 trimethyl) pentyl phosphinic acid) used for preferential separation of lanthanides and actinides in various stages of nuclear fuel cycle. In case of TBP and DHOA complexes, 3 ligand molecules coordinated in monodentate fashion and 3 nitrate ion in bidentate fashion to Eu 3+ to satisfy the 9 coordination of Eu. In case of Cyanex 923 and Cyanex 272 complexes, 3 ligand molecules, 3 nitrate ion and 3 water molecules coordinated to Eu 3+ in monodentate fashion. The Eu complexes of TBP and DHOA were found to have D 3h local symmetry while that for Cyanex 923 and Cyanex 272 were C 3h . Judd-Ofelt analysis of these systems revealed that the covalency of EuO bond followed the trend DHOA>TBP>Cyanex 272>Cyanex 923. Different photophysical properties like radiative and non-radiative life time, branching ratio for different transitions, magnetic and electric dipole moment transition probabilities and quantum efficiency were also evaluated and compared for these systems. The magnetic dipole transition probability was found to be almost independent of ligand field perturbation while electric dipole transition probability for 5 D 0 - 7 F 2 transition was found to be hypersensitive with ligand field with a trend DHOA>TBP>Cyanex 272>Cyanex 923. Copyright © 2016 Elsevier B.V. All rights reserved.

Using continuous monitoring of physical parameters to better estimate phosphorus fluxes in a small agricultural catchment

NASA Astrophysics Data System (ADS)

Minaudo, Camille; Dupas, Rémi; Moatar, Florentina; Gascuel-Odoux, Chantal

2016-04-01

Phosphorus fluxes in streams are subjected to high temporal variations, questioning the relevance of the monitoring strategies (generally monthly sampling) chosen to assist EU Directives to capture phosphorus fluxes and their variations over time. The objective of this study was to estimate the annual and seasonal P flux uncertainties depending on several monitoring strategies, with varying sampling frequencies, but also taking into account simultaneous and continuous time-series of parameters such as turbidity, conductivity, groundwater level and precipitation. Total Phosphorus (TP), Soluble Reactive Phosphorus (SRP) and Total Suspended Solids (TSS) concentrations were surveyed at a fine temporal frequency between 2007 and 2015 at the outlet of a small agricultural catchment in Brittany (Naizin, 5 km2). Sampling occurred every 3 to 6 days between 2007 and 2012 and daily between 2013 and 2015. Additionally, 61 storms were intensively surveyed (1 sample every 30 minutes) since 2007. Besides, water discharge, turbidity, conductivity, groundwater level and precipitation were monitored on a sub-hourly basis. A strong temporal decoupling between SRP and particulate P (PP) was found (Dupas et al., 2015). The phosphorus-discharge relationships displayed two types of hysteretic patterns (clockwise and counterclockwise). For both cases, time-series of PP and SRP were estimated continuously for the whole period using an empirical model linking P concentrations with the hydrological and physic-chemical variables. The associated errors of the estimated P concentrations were also assessed. These « synthetic » PP and SRP time-series allowed us to discuss the most efficient monitoring strategies, first taking into account different sampling strategies based on Monte Carlo random simulations, and then adding the information from continuous data such as turbidity, conductivity and groundwater depth based on empirical modelling. Dupas et al., (2015, Distinct export dynamics for dissolved and particulate phosphorus reveal independent transport mechanisms in an arable headwater catchment, Hydrological Processes, 29(14), 3162-3178

Functionalisation of lanthanide complexes via microwave-enhanced Cu(I)-catalysed azide-alkyne cycloaddition.

PubMed

Szíjjártó, Csongor; Pershagen, Elias; Borbas, K Eszter

2012-07-07

Cu(I)-catalysed azide-alkyne cycloaddition reactions were used to functionalise lanthanide(III)-complexes (Ln; La, Eu and Tb) incorporating alkyne or azide reactive groups. Microwave irradiation significantly accelerated the reactions, enabling full conversion to the triazole products in some cases in 5 min. Alkyl and aryl azides and alkyl and aryl alkynes could all serve as coupling partners. These reaction conditions proved efficient for cyclen-tricarboxylates and previously unreactive cyclen-tris-primary amide chelates. The synthesis of heterobimetallic (Eu/Tb, EuTb17 and Eu/La, EuLa17) and heterotrimetallic (Eu/La/Eu) complexes was achieved in up to 60% isolated yield starting from coumarin 2-appended alkynyl complexes Tb16 or La16 and an azido-Eu complex Eu4, and bis-alkynyl La-complex La5 and Eu4, respectively. EuTb17 displayed dual Eu(III) and Tb(III)-emission upon antenna-centred excitation.

Treatment Parameters and Outcome in 680 Treatments of Internal Radiation With Resin {sup 90}Y-Microspheres for Unresectable Hepatic Tumors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kennedy, Andrew S.; McNeillie, Patrick M.S.; Dezarn, William A.

Purpose: Radioembolization (RE) using {sup 90}Y-microspheres is an effective and safe treatment for patients with unresectable liver malignancies. Radiation-induced liver disease (RILD) is rare after RE; however, greater understanding of radiation-related factors leading to serious liver toxicity is needed. Methods and Materials: Retrospective review of radiation parameters was performed. All data pertaining to demographics, tumor, radiation, and outcomes were analyzed for significance and dependencies to develop a predictive model for RILD. Toxicity was scored using the National Cancer Institute Common Toxicity Criteria Adverse Events Version 3.0 scale. Results: A total of 515 patients (287 men; 228 women) from 14 USmore » and 2 EU centers underwent 680 separate RE treatments with resin {sup 90}Y-microspheres in 2003-2006. Multifactorial analyses identified factors related to toxicity, including activity (GBq) Selective Internal Radiation Therapy delivered (p < 0.0001), prescribed (GBq) activity (p < 0.0001), percentage of empiric activity (GBq) delivered (p < 0.0001), number of prior liver treatments (p < 0.0008), and medical center (p < 0.0001). The RILD was diagnosed in 28 of 680 treatments (4%), with 21 of 28 cases (75%) from one center, which used the empiric method. Conclusions: There was an association between the empiric method, percentage of calculated activity delivered to the patient, and the most severe toxicity, RILD. A predictive model for RILD is not yet possible given the large variance in these data.« less

Temperature dependent luminescence and energy transfer properties of Na2SrMg(PO4)2:Eu2+, Mn2+ phosphors.

PubMed

Geng, Dongling; Shang, Mengmeng; Zhang, Yang; Lian, Hongzhou; Lin, Jun

2013-11-21

Eu(2+) singly and Eu(2+)/Mn(2+) co-doped Na2SrMg(PO4)2 (NSMP) phosphors have been prepared via a high-temperature solid-state reaction process. Upon UV excitation of 260-360 nm, the NSMP:xEu(2+) phosphors exhibit a violet band located at 399 nm and a blue band centered at 445 nm, which originate from Eu(2+) ions occupying two different crystallographic sites: Eu(2+)(I) and Eu(2+)(II), respectively. Excitation wavelengths longer than 380 nm can selectively excite Eu(2+)(II) to emit blue light. Energy transfer processes in the Eu(2+)(I)-Eu(2+)(II) and Eu(2+)-Mn(2+) pairs have been observed and investigated by luminescence spectra and decay curves. The emission color of as-prepared samples can be tuned by changing the relative concentrations of Eu(2+) and Mn(2+) ions and adjusting the excitation wavelength. Under UV excitation of 323 nm, the absolute quantum yield of NSMP:0.005Eu(2+) is 91%, which is higher than most of the other Eu(2+)-doped phosphors reported previously. The temperature dependent luminescence properties and decay curves (4.3-450 K) of NSMP:Eu(2+) and NSMP:Eu(2+), Mn(2+) phosphors have been studied in detail. Thermal quenching of Eu(2+) has been observed while the emission band of Mn(2+) shows a blue-shift and an abnormal increase of intensity with increasing temperature. The unusual thermal quenching behavior indicates that the NSMP compound can serve as a good lattice host for Mn(2+) ions which can be used as a red-emitting phosphor. Additionally, the lifetimes for Eu(2+)(I) and Eu(2+)(II) increase with increasing temperatures.

Direct excitation luminescence spectroscopy of Eu(III) complexes of 1,4,7-tris(carbamoylmethyl)-1,4,7,10- tetraazacyclododecane derivatives and kinetic studies of their catalytic cleavage of an RNA analog.

PubMed

Nwe, Kido; Richard, John P; Morrow, Janet R

2007-11-28

The macrocycles 1,4,7-tris(carbamoylmethyl)-1,4,7,10-tetrazacyclododecane (1), 1,4,7-tris[(N-ethyl)carbamoylmethyl]-1,4,7,10-tetraazacyclododecane (2), 1,4,7-tris[(N,N-diethyl)carbamoylmethyl]-1,4,7,10-tetraazacyclododecane (3) and their Eu(III) complexes are prepared. Studies using direct Eu(III) excitation luminescence spectroscopy show that all three Eu(III) complexes exhibit only one predominant isomer with two bound waters under neutral to mildly basic conditions (Eu(X)(H(2)O)(2) for X = 1-3). There are no detectable ligand ionizations over the pH range 5.0-8.0 for Eu(3), 5.0-8.5 for Eu(2) or 5.0-9.5 for Eu(1). The three Eu(III) complexes show a linear dependence of second-order rate constants for the cleavage of 4-nitrophenyl-2-hydroxyethylphosphate (HpPNP) on pH in the range 6.5-8.0 for Eu(3), 7.0-8.5 for Eu(2) and 7.0-9.0 for Eu(1). This pH-rate profile is consistent with the Eu(III) complex-substrate complex being converted to the active form by loss of a proton and with Eu(III) water pK(a) values that are higher than 8.0 for Eu(3), 8.5 for Eu(2) and 9.0 for Eu(1). Inhibition studies show that Eu() binds strongly to the dianionic ligand methylphosphate (K(d) = 0.28 mM), and more weakly to diethylphosphate (K(d) = 7.5 mM), consistent with a catalytic role of the Eu(III) complexes in stabilizing the developing negative charge on the phosphorane transition state.

Strong Eu2+ light emission in Eu silicate through Eu3+ reduction in Eu2O3/Si multilayer deposited on Si substrates

PubMed Central

2013-01-01

Eu2O3/Si multilayer nanostructured films are deposited on Si substrates by magnetron sputtering. Transmission electron microscopy and X-ray diffraction measurements demonstrate that multicrystalline Eu silicate is homogeneously distributed in the film after high-temperature treatment in N2. The Eu2+ silicate is formed by the reaction of Eu2O3 and Si layers, showing an intense and broad room-temperature photoluminescence peak centered at 610 nm. It is found that the Si layer thickness in nanostructures has great influence on Eu ion optical behavior by forming different Eu silicate crystalline phases. These findings open a promising way to prepare efficient Eu2+ materials for photonic application. PMID:23618344

What the eye does not see: a critical interpretive synthesis of European Union policies addressing sexual violence in vulnerable migrants.

PubMed

Keygnaert, Ines; Guieu, Aurore

2015-11-01

In Europe, refugees, asylum seekers and undocumented migrants are more vulnerable to sexual victimisation than European citizens. They face more challenges when seeking care. This literature review examines how legal and policy frameworks at national, European and international levels condition the prevention of and response to sexual violence affecting these vulnerable migrant communities living in the European Union (EU). Applying the Critical Interpretive Synthesis method, we reviewed 187 legal and policy documents and 80 peer-reviewed articles on migrant sexual health for elements on sexual violence and further analysed the 37 legal and 12 peer-reviewed articles among them that specifically focused on sexual violence in vulnerable migrants in the EU-27 States. Legal and policy documents dealing with sexual violence, particularly but not exclusively in vulnerable migrants, apply 'tunnel vision'. They ignore: a) frequently occurring types of sexual violence, b) victimisation rates across genders and c) specific risk factors within the EU such as migrants' legal status, gender orientation and living conditions. The current EU policy-making paradigm relegates sexual violence in vulnerable migrants as an 'outsider' and 'female only' issue while EU migration and asylum policies reinforce its invisibility. Effective response must be guided by participatory rights- and evidence-based policies and a public health approach, acknowledging the occurrence and multiplicity of sexual victimisation of vulnerable migrants of all genders within EU borders. Copyright © 2015 Elsevier Inc. All rights reserved.

Synthesis and luminescence of Ca 4YO(BO 3) 3:Eu 3+ for fluorescent lamp application

NASA Astrophysics Data System (ADS)

Kuo, Te-Wen; Chen, Teng-Ming

2010-07-01

The red-emitting Ca 4YO(BO 3) 3:Eu 3+ phosphor has been prepared at 1200 °C by the simple solid-state reaction. This preparation temperature is much lower than Y 2O 3:Eu 3+ (1400-1500 °C) for conventional solid-state reaction method. In particular, the complete process to produce high-quality phosphor particles was carried out through the single-step heat treatment of the mixture of corresponding oxide-type metal sources. For this material, the XRD, PL, PL excitation (PLE) and SEM features have also been investigated. The X-ray diffraction data indicate that pure phase of Ca 4YO(BO 3) 3:Eu 3+ can be successfully obtained. Among the different emission transitions 5D 0 → 7F J=0, 1, 2, 3, 4 of this phosphor, one particular transition ( 5D 0 → 7F 2) at 610 nm has been found. Besides carrying out these essential measurements, we have also made an attempt to observe a strong red emission performance displayed by this phosphor for use as coating material on compact fluorescent lamps (CFLs). The results clearly indicate that the life time based on Ca 4YO(BO 3) 3:Eu 3+ was found to be much longer than that using Y 2O 3:Eu 3+. The good performances of the CFLs demonstrate that this phosphor may be suitable for application on short ultraviolet fluorescent lamp.

[The EU Portal: Implementation, importance, and features].

PubMed

von Aschen, Harald; Krafft, Hartmut

2017-08-01

The European Medicines Agency (EMA) is developing a web-based EU portal with a database "at Union level as a single entry point for the submission of data and information relating to clinical trials in accordance with" the new EU regulation No. 536/2014. The specifications are mostly published, but some documents are still missing. Because the project is integrated and has dependencies on other projects, this could result in other specification upgrades. The IT solution is under ongoing development until project completion in quarter III of 2019. The EU Portal and the database will be audited. If the audit is successful, the new regulation will come into force in October 2018. The use of the EU Portal will then be mandatory with some transition rules. The software development of the portal is restricted to the regulation and the derived requirements. It is not possible to implement any national requirements. We describe in this paper the current key functionalities of the portal and try to derive requirements for a national IT system.On 16.06.2017 the EMA Management Board announced that the development of the new portal has been delayed and it is foreseen that the new regulation can come into effect in 2019 at the earliest. The press release can be found here: http://www.ema.europa.eu/ema/index.jsp?curl=pages/news_and_events/news/2017/06/news_detail_002764.jsp%26mid=WC0b01ac058004d5c1 (accessed: 12.07.2017).

Site Occupation of Eu2+ in Ba2- xSr xSiO4 ( x = 0-1.9) and Origin of Improved Luminescence Thermal Stability in the Intermediate Composition.

PubMed

Lin, Litian; Ning, Lixin; Zhou, Rongfu; Jiang, Chunyan; Peng, Mingying; Huang, Yucheng; Chen, Jun; Huang, Yan; Tao, Ye; Liang, Hongbin

2018-06-18

Knowledge of site occupation of activators in phosphors is of essential importance for understanding and tailoring their luminescence properties by modifying the host composition. Relative site preference of Eu 2+ for the two distinct types of alkaline earth (AE) sites in Ba 1.9995- x Sr x Eu 0.0005 SiO 4 ( x = 0-1.9) is investigated based on photoluminescence measurements at low temperature. We found that Eu 2+ prefers to be at the 9-coordinated AE2 site at x = 0, 0.5, and 1.0, while at x = 1.5 and 1.9, it also occupies the 10-coordinated AE1 site with comparable preference, which is verified by density functional theory (DFT) calculations. Moreover, by combining low-temperature measurements of the heat capacity, the host band gap, and the Eu 2+ 4f 7 ground level position, the improved thermal stability of Eu 2+ luminescence in the intermediate composition ( x = 1.0) is interpreted as due to an enlarged energy gap between the emitting 5d level and the bottom of the host conduction band (CB), which results in a decreased nonradiative probability of thermal ionization of the 5d electron into the host CB. Radioluminescence properties of the samples under X-ray excitation are finally evaluated, suggesting a great potential scintillator application of the compound in the intermediate composition.

Photoluminescence of transparent glass-ceramics based on ZnO nanocrystals and co-doped with Eu3+, Yb3+ ions

NASA Astrophysics Data System (ADS)

Arzumanyan, Grigory M.; Kuznetsov, Evgeny A.; Zhilin, Aleksandr A.; Dymshits, Olga S.; Shemchuk, Daria V.; Alekseeva, Irina P.; Mudryi, Alexandr V.; Zhivulko, Vadim D.; Borodavchenko, Olga M.

2016-12-01

Glasses of the K2Osbnd ZnOsbnd Al2O3sbnd SiO2 system co-doped with Eu2O3 and Yb2O3 were prepared by the melt-quenching technique. Transparent zincite (ZnO) glass-ceramics were obtained by secondary heat-treatments at 680-860 °C. At 860 °C, traces of Eu oxyapatite appeared in addition to ZnO nanocrystals. The average crystal size obtained from the X-ray diffraction data was found to range between 14 and 35 nm. Absorption spectra of the initial glasses are composed of an absorption edge and absorption bands due to electronic transitions of Eu3+ ions. With heat-treatment, the absorption edge pronouncedly shifts to the visible spectral range. The luminescence properties of the glass and glass-ceramics were studied by measuring their excitation and emission spectra at 300, 78, and 4.2 K. Strong red emission of Eu3+ ions dominated by the 5D0-7F2 (612 nm) electric dipole transition was detected. Changes in the luminescence properties of the Eu3+-related excitation and emission bands were observed after heat-treatments at 680 °C and 860 °C. The ZnO nanocrystals showed both broad luminescence (400-850 nm) and free-exciton emission near 3.3 eV at room temperature. The upconversion luminescence spectrum of the initial glass was obtained under excitation of the 976 nm laser source.

Resonant TMR inversion in LiF/EuS based spin-filter tunnel junctions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liu, Fen; Chen, Aixi; Institute for Quantum Computing & Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, ON N2L 3G1 Canada

Resonant tunneling can lead to inverse tunnel magnetoresistance when impurity levels rather than direct tunneling dominate the transport process. We fabricated hybrid magnetic tunnel junctions of CoFe/LiF/EuS/Ti, with an epitaxial LiF energy barrier joined with a polycrystalline EuS spin-filter barrier. Due to the water solubility of LiF, the devices were fully packaged in situ. The devices showed sizeable positive TMR up to 16% at low bias voltages but clearly inverted TMR at higher bias voltages. The TMR inversion depends sensitively on the thickness of LiF, and the tendency of inversion disappears when LiF gets thick enough and recovers its intrinsicmore » properties.« less

Estimation of incidence and social cost of colon cancer due to nitrate in drinking water in the EU: a tentative cost-benefit assessment.

PubMed

van Grinsven, Hans J M; Rabl, Ari; de Kok, Theo M

2010-10-06

Presently, health costs associated with nitrate in drinking water are uncertain and not quantified. This limits proper evaluation of current policies and measures for solving or preventing nitrate pollution of drinking water resources. The cost for society associated with nitrate is also relevant for integrated assessment of EU nitrogen policies taking a perspective of welfare optimization. The overarching question is at which nitrogen mitigation level the social cost of measures, including their consequence for availability of food and energy, matches the social benefit of these measures for human health and biodiversity. Epidemiological studies suggest colon cancer to be possibly associated with nitrate in drinking water. In this study risk increase for colon cancer is based on a case-control study for Iowa, which is extrapolated to assess the social cost for 11 EU member states by using data on cancer incidence, nitrogen leaching and drinking water supply in the EU. Health costs are provisionally compared with nitrate mitigation costs and social benefits of fertilizer use. For above median meat consumption the risk of colon cancer doubles when exposed to drinking water exceeding 25 mg/L of nitrate (NO3) for more than ten years. We estimate the associated increase of incidence of colon cancer from nitrate contamination of groundwater based drinking water in EU11 at 3%. This corresponds to a population-averaged health loss of 2.9 euro per capita or 0.7 euro per kg of nitrate-N leaching from fertilizer. Our cost estimates indicate that current measures to prevent exceedance of 50 mg/L NO3 are probably beneficial for society and that a stricter nitrate limit and additional measures may be justified. The present assessment of social cost is uncertain because it considers only one type of cancer, it is based on one epidemiological study in Iowa, and involves various assumptions regarding exposure. Our results highlight the need for improved epidemiological studies.

High prevalence but limited evidence in complementary and alternative medicine: guidelines for future research

PubMed Central

2014-01-01

The use of complementary and alternative Medicine (CAM) has increased over the past two decades in Europe. Nonetheless, research investigating the evidence to support its use remains limited. The CAMbrella project funded by the European Commission aimed to develop a strategic research agenda starting by systematically evaluating the state of CAM in the EU. CAMbrella involved 9 work packages covering issues such as the definition of CAM; its legal status, provision and use in the EU; and a synthesis of international research perspectives. Based on the work package reports, we developed a strategic and methodologically robust research roadmap based on expert workshops, a systematic Delphi-based process and a final consensus conference. The CAMbrella project suggests six core areas for research to examine the potential contribution of CAM to the health care challenges faced by the EU. These areas include evaluating the prevalence of CAM use in Europe; the EU cititzens’ needs and attitudes regarding CAM; the safety of CAM; the comparative effectiveness of CAM; the effects of meaning and context on CAM outcomes; and different models for integrating CAM into existing health care systems. CAM research should use methods generally accepted in the evaluation of health services, including comparative effectiveness studies and mixed-methods designs. A research strategy is urgently needed, ideally led by a European CAM coordinating research office dedicated to fostering systematic communication between EU governments, the public, charitable and industry funders, researchers and other stakeholders. A European Centre for CAM should also be established to monitor and further a coordinated research strategy with sufficient funds to commission and promote high quality, independent research focusing on the public’s health needs and pan-European collaboration. There is a disparity between highly prevalent use of CAM in Europe and solid knowledge about it. A strategic approach on CAM research should be established to investigate the identified gaps of knowledge and to address upcoming health care challenges. PMID:24499316

Synthesis, crystal structures, and physical properties of the new Zintl phases A{sub 21}Zn{sub 4}Pn{sub 18} (A=Ca, Eu; Pn=As, Sb)—Versatile arrangements of [ZnPn{sub 4}] tetrahedra

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suen, Nian-Tzu; Wang, Yi; Bobev, Svilen, E-mail: bobev@udel.edu

Four new Zintl phases, Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18} and Eu{sub 21}Zn{sub 4}Sb{sub 18} have been synthesized by metal flux reactions. Their structures have been established from single-crystal X-ray diffraction. Despite the similar chemical makeup and the identical formulae, the structures of the four compounds are not the same—Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18} and Eu{sub 21}Zn{sub 4}As{sub 18} crystallize in the monoclinic space group C2/m (No. 12, Z=4) with the β-Ca{sub 21}Mn{sub 4}Sb{sub 18} structure type, while Eu{sub 21}Zn{sub 4}Sb{sub 18} adopts the Ba{sub 21}Cd{sub 4}Sb{sub 18} structure type withmore » the orthorhombic space group Cmce (No. 64, Z=8). Both structures are based on ZnAs{sub 4} or ZnSb{sub 4} tetrahedra, linked in slightly different ways, and Ca{sup 2+} and Eu{sup 2+} cations that fill the space between them. The structural relationships between the title compounds and other known ternary phases with intricate structures are discussed. Electrical resistivity measurement on single-crystalline Eu{sub 21}Zn{sub 4}Sb{sub 18} suggests an intrinsic semiconductor behavior with a band gap of ca. 0.2 eV. The temperature dependent DC magnetization measurement on the same material indicates Curie–Weiss paramagnetism in the high-temperature regime, and a spontaneous antiferromagnetic ordering below 8 K. The calculated effective moments of Eu confirm the divalent Eu{sup 2+} ground state, as expected from the Zintl–Klemm concept. - Graphical abstract: The four new Zintl phases—Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18}, and Eu{sub 21}Zn{sub 4}Sb{sub 18}—crystallize in two structure types, showing the versatility in the arrangements of ZnAs{sub 4} and ZnSb{sub 4} tetrahedra. - Highlights: • Ca{sub 21}Zn{sub 4}As{sub 18}, Ca{sub 21}Zn{sub 4}Sb{sub 18}, Eu{sub 21}Zn{sub 4}As{sub 18}, and Eu{sub 21}Zn{sub 4}Sb{sub 18} are new compounds in the respective ternary phase diagrams. • They form with structure types, showing the versatility in the arrangements of ZnAs{sub 4} and ZnSb{sub 4} tetrahedra. • For both structures, the valence electron count follows the Zintl–Klemm rules.« less

Tunable emission in lanthanide coordination polymer gels based on a rationally designed blue emissive gelator.

PubMed

Sutar, Papri; Suresh, Venkata M; Maji, Tapas Kumar

2015-06-18

Rational design and synthesis of a new low molecular weight gelator (LMWG) having 9,10-diphenylanthracene core and terminal terpyridine is reported. Tb(III) and Eu(III) ion coordination to a LMWG results in green and pink emissive coordination polymer gels, respectively, with coiled nanofiber morphology. Further, control over stoichiometry of LMWG:Tb(III):Eu(III) leads to yellow and white light emitting bimetallic gels.

Economic efficiency versus social equality? The U.S. liberal model versus the European social model.

PubMed

Navarro, Vicente; Schmitt, John

2005-01-01

This article begins by challenging the widely held view in neoliberal discourse that there is a necessary trade-off between higher efficiency and lower reduction of inequalities: the article empirically shows that the liberal, U.S. model has been less efficient economically (slower economic growth, higher unemployment) than the social model in existence in the European Union and in the majority of its member states. Based on the data presented, the authors criticize the adoption of features of the liberal model (such as deregulation of their labor markets, reduction of public social expenditures) by some European governments. The second section analyzes the causes for the slowdown of economic growth and the increase of unemployment in the European Union--that is, the application of monetarist and neoliberal policies in the institutional frame of the European Union, including the Stability Pact, the objectives and modus operandi of the European Central Bank, and the very limited resources available to the European Commission for stimulating and distributive functions. The third section details the reasons for these developments, including (besides historical considerations) the enormous influence of financial capital in the E.U. institutions and the very limited democracy. Proposals for change are included.

Internal heat gain from different light sources in the building lighting systems

NASA Astrophysics Data System (ADS)

Suszanowicz, Dariusz

2017-10-01

EU directives and the Construction Law have for some time required investors to report the energy consumption of buildings, and this has indeed caused low energy consumption buildings to proliferate. Of particular interest, internal heat gains from installed lighting affect the final energy consumption for heating of both public and residential buildings. This article presents the results of analyses of the electricity consumption and the luminous flux and the heat flux emitted by different types of light sources used in buildings. Incandescent light, halogen, compact fluorescent bulbs, and LED bulbs from various manufacturers were individually placed in a closed and isolated chamber, and the parameters for their functioning under identical conditions were recorded. The heat flux emitted by 1 W nominal power of each light source was determined. Based on the study results, the empirical coefficients of heat emission and energy efficiency ratios for different types of lighting sources (dependent lamp power and the light output) were designated. In the heat balance of the building, the designated rates allow for precise determination of the internal heat gains coming from lighting systems using various light sources and also enable optimization of lighting systems of buildings that are used in different ways.

Engaging technology-resistant elderly people: Empirical evidence from an ICT-enabled social environment.

PubMed

Papa, Filomena; Cornacchia, Michele; Sapio, Bartolomeo; Nicolò, Enrico

2017-01-01

This paper presents a qualitative investigation on user reactions, opinions, and sentiments about a TV-based technological solution developed within the EasyReach Project of the EU Ambient Assisted Living Joint Program to promote social interaction of less educated elderly people, that is, those individuals who, because of poor scholarization, low income, and, possibly, linguistic barriers, still find it difficult to use computers in order to improve their socialization. Experimental data were collected by extensive trials involving 40 real-end users. A methodology called "scenario engagement" was applied to get participants engaged in a live demonstration with the mediation of a facilitator who assisted elderly people to interact with the system. Results point out that the system can be effectively employed to foster social interaction, particularly when it is introduced in a collective use environment (e.g., Senior Center). Although the focus of the investigation was on information and communication technology-enabled social environments, the end users themselves strongly suggested to include in future system releases extra functions considered as essential opportunities for their potential digital lives: that is, medical or health services and bridges toward public administration.

Pressure-induced valence change and moderate heavy fermion state in Eu-compounds

NASA Astrophysics Data System (ADS)

Honda, Fuminori; Okauchi, Keigo; Sato, Yoshiki; Nakamura, Ai; Akamine, Hiromu; Ashitomi, Yosuke; Hedo, Masato; Nakama, Takao; Takeuchi, Tetsuya; Valenta, Jaroslav; Prchal, Jiri; Sechovský, Vladimir; Aoki, Dai; Ōnuki, Yoshichika

2018-05-01

A pressure-induced valence transition has attracted much attention in Eu-compounds. Among them, EuRh2Si2, EuNi2Ge2, and EuCo2Ge2 reveal the valence transition around 1, 2, and 3 GPa, respectively. We have succeeded in growing single crystals of EuT2X2 (T: transition metal, X: Si, Ge) and studied electronic properties under pressure. EuRh2Si2 indicates a first-order valence transition between 1 and 2 GPa, with a large and prominent hysteresis in the electrical resistivity. At higher pressures, the first-order valence transition changes to a cross-over regime with an intermediate valence state. Tuning of the valence state with pressure is reflected in a drastic change of the temperature dependence of the electrical resistivity in EuRh2Si2 single crystals. Effect of pressure on the valence states on EuRh2Si2, EuIr2Si2, EuNi2Ge2, and EuCo2Ge2, as well as an isostructural related compound EuGa4, are reviewed.

Active animal health surveillance in European Union Member States: gaps and opportunities.

PubMed

Bisdorff, B; Schauer, B; Taylor, N; Rodríguez-Prieto, V; Comin, A; Brouwer, A; Dórea, F; Drewe, J; Hoinville, L; Lindberg, A; Martinez Avilés, M; Martínez-López, B; Peyre, M; Pinto Ferreira, J; Rushton, J; VAN Schaik, G; Stärk, K D C; Staubach, C; Vicente-Rubiano, M; Witteveen, G; Pfeiffer, D; Häsler, B

2017-03-01

Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.

Ferromagnetic behavior in mixed valence europium (Eu2+/Eu3+) oxide EuTi1-xMxO3 (M = Al3+ and Ga3+)

NASA Astrophysics Data System (ADS)

Akahoshi, Daisuke; Horie, Hiroki; Sakai, Shingo; Saito, Toshiaki

2013-10-01

We have investigated the Ti-site substitution effect on the magnetic properties of antiferromagnetic insulator EuTiO3 with a Néel temperature of ˜5 K. Partial substitution of Ti4+ with heterovalent Al3+ or Ga3+ turns the corresponding amount of magnetic Eu2+ into non-magnetic Eu3+. Both EuTi1-xAlxO3 (0.05 ≤ x ≤ 0.10) and EuTi1-xGaxO3 (0.05 ≤ x ≤ 0.10) exhibit ferromagnetic (FM) insulating behavior below ˜4 K. The Eu2+/Eu3+ mixed valence state probably contributes to the emergence of the FM behavior. Fine control of the magneto-electric (ME) phases of EuTi1-xAlxO3 and EuTi1-xGaxO3 would lead to intriguing ME phenomena such as giant ME effect.

First-principles calculation on electronic structure and optical property of BaSi{sub 2}O{sub 2}N{sub 2}:Eu{sup 2+} phosphor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tong, Zhi-Fang, E-mail: tongzhifang1998@126.com; Wei, Zhan-Long; Xiao, Cheng

The crystal structure, electronic structure and optical properties of BaSi{sub 2}O{sub 2}N{sub 2}:Eu{sup 2+} with varying Eu doping concentrations are computed by the density functional theory (DFT) and compared with experimental results. The results show that the lattice parameters of primitive cells of Ba{sub 1−x}Si{sub 2}O{sub 2}N{sub 2}:Eu{sub x} become smaller and Eu–N bond length shortens as Eu concentration increases. The band structure of Ba{sub 1−x}Si{sub 2}O{sub 2}N{sub 2}:Eu{sub x} exhibits a direct optical band gap and it's propitious to luminescence. The energy differences from the lowest Eu 5d state to the lowest Eu 4f state decrease with increasing Eumore » concentrations. The analysis of simulative absorption spectra indicates that the electron transition from Eu 4f states to 5d states of both Eu and Ba atoms contributes to the absorption of Ba{sub 1−x}Si{sub 2}O{sub 2}N{sub 2}:Eu{sub x}. Under the coupling effect between Eu and Ba, Ba in BaSi{sub 2}O{sub 2}N{sub 2} exhibits longer wavelength absorption and increases absorption efficiency. The emission wavelength is deduced by measuring energy differences from the lowest Eu 5d state to the lowest Eu 4f state, and the result is in good agreement with experimental value within experimental Eu{sup 2+} doping range. - Graphical abstract: The structure and optical property of BaSi{sub 2}O{sub 2}N{sub 2}:Eu{sup 2+} are computed by DFT and its absorption mechanism is analysed. Results show that absorption peak α is from the host lattice absorption. The absorption peaks β, γ and δ are from Eu 4f to Eu 5d and Ba 6s 5d states. The absorption is attributed to the coupling effect of Eu and Ba atom. - Highlights: • The crystal, electronic structure and optical properties of BaSi{sub 2}O{sub 2}N{sub 2}:Eu{sup 2+} are computed by DFT. • The lattice parameters of primitive cells reduces and Eu–N bond length shortens as Eu{sup 2+} increases. • The energy gap from Eu 5d state to Eu 4f state decrease with increasing Eu concentrations. • Both Eu and Ba atoms contributes to the absorption of Ba{sub 1−x}Si{sub 2}O{sub 2}N{sub 2}:Eu{sub x}. • The deduced emission wavelength is in good agreement with experimental value.« less

Regulatory aspects of nanotechnology in the agri/feed/food sector in EU and non-EU countries.

PubMed

Amenta, Valeria; Aschberger, Karin; Arena, Maria; Bouwmeester, Hans; Botelho Moniz, Filipa; Brandhoff, Puck; Gottardo, Stefania; Marvin, Hans J P; Mech, Agnieszka; Quiros Pesudo, Laia; Rauscher, Hubert; Schoonjans, Reinhilde; Vettori, Maria Vittoria; Weigel, Stefan; Peters, Ruud J

2015-10-01

Nanotechnology has the potential to innovate the agricultural, feed and food sectors (hereinafter referred to as agri/feed/food). Applications that are marketed already include nano-encapsulated agrochemicals or nutrients, antimicrobial nanoparticles and active and intelligent food packaging. Many nano-enabled products are currently under research and development, and may enter the market in the near future. As for any other regulated product, applicants applying for market approval have to demonstrate the safe use of such new products without posing undue safety risks to the consumer and the environment. Several countries all over the world have been active in examining the appropriateness of their regulatory frameworks for dealing with nanotechnologies. As a consequence of this, different approaches have been taken in regulating nano-based products in agri/feed/food. The EU, along with Switzerland, were identified to be the only world region where nano-specific provisions have been incorporated in existing legislation, while in other regions nanomaterials are regulated more implicitly by mainly building on guidance for industry. This paper presents an overview and discusses the state of the art of different regulatory measures for nanomaterials in agri/feed/food, including legislation and guidance for safety assessment in EU and non-EU countries. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

White LED based on CaAl2Si2O8:Eu2+ Mn2+ phosphor and CdS/ZnS quantum dots

NASA Astrophysics Data System (ADS)

Shen, Changyu; Zhong, Chuan; Hou, Qianglong; Li, Ke

2011-02-01

Core/shell CdS/ZnS quantum dots (QDs) with the emission wavelength of 610nm, was synthesized by thermal deposition using cadmium oxide and selenium as precursors in a hot lauric acid and hexadecylamine trioctylphosphine oxide hybrid. CaAl2Si2O8:Eu2+ Mn2+ phosphor was synthesized by high-temperature solid state reaction at 1290 °C for 2 hours under the H2 reducing atmosphere, and X-ray powder diffraction analysis confirmed the formation of it. It has two emission bands peaking at 420 nm and 580nm originated from the transition 5d to 4f of Eu2+ and 4T1-6A1 of Mn2+, respectively. Blends of CaAl2Si2O8:Eu2+,Mn2+ phosphor and CdS/ZnS QDs exhibited the prominent spectral evolution with an increasing content of QDs. A hybrid white LED, which combines a blue LED with the blend of CaAl2Si2O8:Eu2+ Mn2+ phosphor and QDs with a weight ratio of 2:1, with the CIE coordinate of (0.3183, 0.3036) and CRI of 85 was obtained.

Structural and photoluminescence properties of stannate based displaced pyrochlore-type red phosphors: Ca(3-x)Sn₃Nb₂O₁₄:xEu³⁺.

PubMed

Sreena, T S; Prabhakar Rao, P; Francis, T Linda; Raj, Athira K V; Babu, Parvathi S

2015-05-14

New stannate based displaced pyrochlore-type red phosphors, Ca(3-x)Sn3Nb2O14:xEu(3+), were prepared via a conventional solid state method. The influence of partial occupancy of Sn in both A and B sites of the pyrochlore-type oxides on the photoluminescence properties was studied using powder X-ray diffraction, FT-Raman, transmission electron microscopy, scanning electron microscopy with energy dispersive spectrometry, UV-visible absorption spectroscopy, and photoluminescence excitation and emission spectra with lifetime measurements. The structural analysis establishes that these oxides belong to a cubic displaced pyrochlore type structure with a space group Fd3̄m. These phosphors exhibit strong absorptions at near UV and blue wavelength regions and emit intense multiband emissions due to Eu(3+ 5)D0-(7)F(0, 1, 2) transitions. The absence of characteristic MD transition splitting points out that local cation disorder exists in this type of displaced pyrochlores, reducing the D(3d) inversion symmetry, which is not evidenced by such disorder in the X-ray diffraction analysis. The unusual forbidden intense sharp (5)D0-(7)F0 transition indicates single site occupancy of Eu(3+) with a narrower range of bonding environment, preventing the cluster formation. This is supported by the stable (5)D0 lifetime with Eu(3+) concentration. The Judd-Ofelt intensity parameter assessment corroborates these results. The CIE color coordinates of these phosphors were found to be (0.60, 0.40), which are close to the NTSC standard values (0.67, 0.33) for a potential red phosphor.

Evidence for biphasic uncoating during HIV-1 infection from a novel imaging assay

PubMed Central

2013-01-01

Background Uncoating of the HIV-1 core plays a critical role during early post-fusion stages of infection but is poorly understood. Microscopy-based assays are unable to easily distinguish between intact and partially uncoated viral cores. Results In this study, we used 5-ethynyl uridine (EU) to label viral-associated RNA during HIV production. At early time points after infection with EU-labeled virions, the viral-associated RNA was stained with an EU-specific dye and was detected by confocal microscopy together with viral proteins. We observed that detection of the viral-associated RNA was specific for EU-labeled virions, was detected only after viral fusion with target cells, and occurred after an initial opening of the core. In vitro staining of cores showed that the opening of the core allowed the small molecule dye, but not RNase A or antibodies, inside. Also, staining of the viral-associated RNA, which is co-localized with nucleocapsid, decays over time after viral infection. The decay rate of RNA staining is dependent on capsid (CA) stability, which was altered by CA mutations or a small molecule inducer of HIV-1 uncoating. While the staining of EU-labeled RNA was not affected by inhibition of reverse transcription, the kinetics of core opening of different CA mutants correlated with initiation of reverse transcription. Analysis of the E45A CA mutant suggests that initial core opening is independent of complete capsid disassembly. Conclusions Taken together, our results establish a novel RNA accessibility-based assay that detects an early event in HIV-1 uncoating and can be used to further define this process. PMID:23835323

Concurrent validation of two key health literacy instruments in a South Eastern European population.

PubMed

Toçi, Ervin; Burazeri, Genc; Sørensen, Kristine; Kamberi, Haxhi; Brand, Helmut

2015-06-01

Public health practice has come to increasing recognition of health promotion and the central role of knowledge, attitude, beliefs and practices in achieving health promotion. Health literacy (HL) is an under-explored topic in South Eastern European countries. There are no HL reports from Albania to date. The aim of this study was to assess the concurrent validity of the European Health Literacy Survey Questionnaire (HLS-EU-Q) and the Test of Functional Health Literacy in Adults (TOFHLA) in a population-based sample of adults in Albania. A cross-sectional study was conducted in 2013 in Tirana, Albania, including 239 individuals aged ≥ 18 years (61% women; 87% response). A structured interviewer-administered questionnaire was applied twice (test and retest procedure after 2 weeks) including HLS-EU-Q and TOFHLA instruments. The internal consistency was high for both instruments (Cronbach's alpha for the test procedure was 0.92 for TOFHLA and 0.98 for HLS-EU-Q). Both tools exhibited a high stability over time (Spearman's rho: 0.88 for TOFHLA and 0.87 for HLS-EU). Mean values of both instruments were similar in men and women (mean score for TOFHLA: 76.0 vs. 76.5, P = 0.83; mean score for HLS-EU-Q: 32.2 vs. 32.6, P = 0.63). For both instruments, higher HL scores were significantly associated with younger age, higher educational and economic level and lower body mass index. Our study provides valuable novel evidence on concurrent validation of two major HL instruments in a South Eastern European population-based sample. Future studies should be conducted in order to confirm and expand our findings. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

A EUropean study on effectiveness and sustainability of current Cardiac Rehabilitation programmes in the Elderly: Design of the EU-CaRE randomised controlled trial.

PubMed

Prescott, Eva; Meindersma, Esther P; van der Velde, Astrid E; Gonzalez-Juanatey, Jose R; Iliou, Marie Christine; Ardissino, Diego; Zoccai, Giuseppe Biondi; Zeymer, Uwe; Prins, Leonie F; Van't Hof, Arnoud Wj; Wilhelm, Matthias; de Kluiver, Ed P

2016-10-01

Cardiac rehabilitation (CR) is an evidence-based intervention to increase survival and quality of life. Yet studies consistently show that elderly patients are less frequently referred to CR, show less uptake and more often drop out of CR programmes. The European study on effectiveness and sustainability of current cardiac rehabilitation programmes in the elderly (EU-CaRE) project consists of an observational study and an open prospective, investigator-initiated multicentre randomised controlled trial (RCT) involving mobile telemonitoring guided CR (mCR). The aim of EU-CaRE is to map the efficiency of current CR of the elderly in Europe, and to investigate whether mCR is an effective alternative in terms of efficacy, adherence and sustainability. The EU-CaRE study includes patients aged 65 years or older with ischaemic heart disease or who have undergone heart valve surgery. A total of 1760 patients participating in existing CR programmes in eight regions of Europe will be included. Of patients declining regular CR, 238 will be included in the RCT and randomised in two study arms. The experimental group (mCR) will receive a personalised home-based programme while the control group will receive no advice or coaching throughout the study period. Outcomes will be assessed after the end of CR and at 12 months follow-up. The primary outcome is VO 2peak and secondary outcomes include variables describing CR uptake, adherence, efficacy and sustainability. The study will provide important information to improve CR in the elderly. The EU-CaRE RCT is the first European multicentre study of mCR as an alternative for elderly patients not attending usual CR. © The European Society of Cardiology 2016.

Enhancing participatory approach in water resources management: development of a survey to evaluate stakeholders needs and priorities related to software capabilities

NASA Astrophysics Data System (ADS)

Foglia, L.; Rossetto, R.; Borsi, I.; Josef, S.; Boukalova, Z.; Triana, F.; Ghetta, M.; Sabbatini, T.; Bonari, E.; Cannata, M.; De Filippis, G.

2016-12-01

The EU H2020 FREEWAT project (FREE and open source software tools for WATer resource management) aims at simplifying the application of EU-water related Directives, by developing an open source and public domain, GIS-integrated platform for planning and management of ground- and surface-water resources. The FREEWAT platform is conceived as a canvas, where several distributed and physically-based simulation codes are virtually integrated. The choice of such codes was supported by the result of a survey performed by means of questionnaires distributed to 14 case study FREEWAT project partners and several stakeholders. This was performed in the first phase of the project within the WP 6 (Enhanced science and participatory approach evidence-based decision making), Task 6.1 (Definition of a "needs/tools" evaluation grid). About 30% among all the invited entities and institutions from several EU and non-EU Countries expressed their interest in contributing to the survey. Most of them were research institutions, government and geoenvironmental companies and river basin authorities.The result of the questionnaire provided a spectrum of needs and priorities of partners/stakeholders, which were addressed during the development phase of the FREEWAT platform. The main needs identified were related to ground- and surface-water quality, sustainable water management, interaction between groundwater/surface-water bodies, and design and management of Managed Aquifer Recharge schemes. Needs and priorities were then connected to the specific EU Directives and Regulations to be addressed.One of the main goals of the questionnaires was to collect information and suggestions regarding the use of existing commercial/open-source software tools to address needs and priorities, and regarding the needs to address specific water-related processes/problems.

Eu 2+ –Eu 3+ valence transition in double, Eu-, and Na-doped PbSe from transport, magnetic, and electronic structure studies

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiendlocha, Bartlomiej; Kim, SunPhil; Lee, Yeseul

The Eu atoms in Pb 1-xEu xSe have long been assumed to be divalent. We show that p-type doping of this magnetic semiconductor alloy with Na can modify the effective Eu valence: a mixed, Eu 2+–Eu 3+ state appears in Pb 1-x-yEu xNa ySe at particular values of y. Magnetization, carrier concentration, resistivity, and thermopower of Pb 1-x-yEu xNa ySe are reported for a number of samples with different x and y. A pronounced increase in thermopower at a given carrier concentration was identified and attributed to the presence of enhanced ionized impurity scattering. A strong decrease in the holemore » concentration is observed in Pb1-yNaySe when Eu is added to the system, which we attribute to a Eu 2+–Eu 3+ self-ionization process. This is evidenced by magnetization measurements, which reveal a significant reduction of the magnetic moment of Pb 1-xEu xSe upon alloying with Na. Further, a deviation of magnetization from a purely paramagnetic state, described by a Brillouin function, identifies antiferromagnetic interactions between the nearest-neighbor Eu atoms: a value of J ex/k B = -0.35 K was found for the exchange coupling parameter. The conclusion of a Eu 2+–Eu 3+ self-ionization process being in effect is supported further by the electronic structure calculations, which show that an instability of the 4f 7 configuration of the Eu 2+ ion appears with Na doping. In conclusion, schematically, it was found that the Eu 4f levels form states near enough to the Fermi energy that hole doping can lower the Fermi energy and trigger a reconfiguration of a 4f electronic shell.« less

Eu 2+ –Eu 3+ valence transition in double, Eu-, and Na-doped PbSe from transport, magnetic, and electronic structure studies

DOE PAGES

Wiendlocha, Bartlomiej; Kim, SunPhil; Lee, Yeseul; ...

2017-03-27

The Eu atoms in Pb 1-xEu xSe have long been assumed to be divalent. We show that p-type doping of this magnetic semiconductor alloy with Na can modify the effective Eu valence: a mixed, Eu 2+–Eu 3+ state appears in Pb 1-x-yEu xNa ySe at particular values of y. Magnetization, carrier concentration, resistivity, and thermopower of Pb 1-x-yEu xNa ySe are reported for a number of samples with different x and y. A pronounced increase in thermopower at a given carrier concentration was identified and attributed to the presence of enhanced ionized impurity scattering. A strong decrease in the holemore » concentration is observed in Pb1-yNaySe when Eu is added to the system, which we attribute to a Eu 2+–Eu 3+ self-ionization process. This is evidenced by magnetization measurements, which reveal a significant reduction of the magnetic moment of Pb 1-xEu xSe upon alloying with Na. Further, a deviation of magnetization from a purely paramagnetic state, described by a Brillouin function, identifies antiferromagnetic interactions between the nearest-neighbor Eu atoms: a value of J ex/k B = -0.35 K was found for the exchange coupling parameter. The conclusion of a Eu 2+–Eu 3+ self-ionization process being in effect is supported further by the electronic structure calculations, which show that an instability of the 4f 7 configuration of the Eu 2+ ion appears with Na doping. In conclusion, schematically, it was found that the Eu 4f levels form states near enough to the Fermi energy that hole doping can lower the Fermi energy and trigger a reconfiguration of a 4f electronic shell.« less

Synthesis and effect of Ce and Mn co-doping on photoluminescence characteristics of Ca6AlP5O20:Eu novel phosphors.

PubMed

Shinde, K N; Dhoble, S J

2013-01-01

A series of Ca6AlP5O20 doped with rare earths (Eu and Ce) and co-doped (Eu, Ce and Eu,Mn) were prepared by combustion synthesis. Under Hg-free excitation, Ca6AlP5O20:Eu exhibited Eu(2+) (486 nm) emission in the blue region of the spectrum and under near Hg excitation (245 nm), Ca6AlP5O20:Ce phosphor exhibited Ce(3+) emission (357 nm) in the UV range. Photoluminescence (PL) peak intensity increased in Ca6AlP5O20:Eu,Ce and Ca6AlP5O20:Eu, Mn phosphors due to co-activators of Ce(3+) and Mn(2+) ions. As a result, these ions played an important role in PL emission in the present matrix. Ca6AlP5O20:Eu, Ce and Ca6AlP5O20:Eu, Mn phosphors provided energy transfer mechanisms via Ce(3+) → Eu(2+) and Eu(2+) → Mn(2+), respectively. Eu ions acted as activators and Ce ions acted as sensitizers. Ce emission energy was well matched with Eu excitation energy in the case of Ca6AlP5O20:Eu, Ce and Eu ions acted as activators and Mn ions acted as sensitizers in Ca6AlP5O20:Eu, Mn. This study included synthesis of new and efficient phosphate phosphors. The impact of doping and co-doping on photoluminescence properties and energy transfer mechanisms were investigated and we propose a feasible interpretation. Copyright © 2012 John Wiley & Sons, Ltd.

Elimination of trachoma as a public health problem in Ghana: Providing evidence through a pre-validation survey

PubMed Central

Debrah, Oscar; Mensah, Ernest O.; Senyonjo, Laura; de Souza, Dziedzom K.; Hervie, Tei E.; Agyemang, David; Bakajika, Didier; Marfo, Benjamin; Ahorsu, Felix; Wanye, Seth; Bailey, Robin; Koroma, Joseph B.; Aboe, Agatha

2017-01-01

Background In order to achieve elimination of trachoma, a country needs to demonstrate that the elimination prevalence thresholds have been achieved and then sustained for at least a two-year period. Ghana achieved the thresholds in 2008, and since 2011 has been implementing its trachoma surveillance strategy, which includes community and school screening for signs of follicular trachoma and trichiasis, in trachoma-endemic districts. In 2015–2016, the country conducted a district level population-based survey to validate elimination of trachoma as a public health problem. Methods As per WHO recommendations, a cross-sectional survey, employing a two-stage cluster random sampling methodology, was used across 18 previously trachoma endemic districts (evaluation units (EUs) in the Upper West and Northern Regions of Ghana. In each EU 24 villages were selected based on probability proportional to estimated size. A minimum of 40 households were targeted per village and all eligible residents were examined for clinical signs of trachoma, using the WHO simplified grading system. The number of trichiasis cases unknown to the health system was determined. Household environmental risk factors for trachoma were also assessed. Results Data from 45,660 individuals were examined from 11,099 households across 18 EUs, with 27,398 (60.0%) children aged 1–9 years and 16,610 (36.4%) individuals 15 years and above All EUs had shown to have maintained the WHO elimination threshold for Trachomatous inflammation-Follicular (TF) (<5.0% prevalence) in children aged 1–9 years old. The EU TF prevalence in children aged 1–9 years old ranged from between 0.09% to 1.20%. Only one EU (Yendi 0.36%; 95% CI: 0.0–1.01) failed to meet the WHO TT elimination threshold (< 0.2% prevalence in adults aged 15 and above). The EU prevalence of trichiasis (TT) unknown to the health system in adults aged ≥15 years, ranged from 0.00% to 0.36%. In this EU, the estimated TT backlog is 417 All TT patients identified in the study, as well as through on-going surveillance efforts will require further management. A total of 75.9% (95% CI 72.1–79.3, EU range 29.1–92.6) of households defecated in the open but many households had access to an improved water source 75.9% (95%CI: 71.5–79.8, EU range 47.4–90.1%), with 45.5% (95% CI 41.5–49.7%, EU range 28.4–61.8%) making a round trip of water collection < 30 minutes. Conclusion The findings from this survey indicate elimination thresholds have been maintained in Ghana in 17 of the 18 surveyed EUs. Only one EU, Yendi, did not achieve the TT elimination threshold. A scheduled house-by-house TT case search in this EU coupled with surgery to clear the backlog of cases is necessary in order for Ghana to request validation of elimination of trachoma as a public health problem. PMID:29232708

Comparative development of knowledge-based bioeconomy in the European Union and Turkey.

PubMed

Celikkanat Ozan, Didem; Baran, Yusuf

2014-09-01

Biotechnology, defined as the technological application that uses biological systems and living organisms, or their derivatives, to create or modify diverse products or processes, is widely used for healthcare, agricultural and environmental applications. The continuity in industrial applications of biotechnology enables the rise and development of the bioeconomy concept. Bioeconomy, including all applications of biotechnology, is defined as translation of knowledge received from life sciences into new, sustainable, environment friendly and competitive products. With the advanced research and eco-efficient processes in the scope of bioeconomy, more healthy and sustainable life is promised. Knowledge-based bioeconomy with its economic, social and environmental potential has already been brought to the research agendas of European Union (EU) countries. The aim of this study is to summarize the development of knowledge-based bioeconomy in EU countries and to evaluate Turkey's current situation compared to them. EU-funded biotechnology research projects under FP6 and FP7 and nationally-funded biotechnology projects under The Scientific and Technological Research Council of Turkey (TUBITAK) Academic Research Funding Program Directorate (ARDEB) and Technology and Innovation Funding Programs Directorate (TEYDEB) were examined. In the context of this study, the main research areas and subfields which have been funded, the budget spent and the number of projects funded since 2003 both nationally and EU-wide and the gaps and overlapping topics were analyzed. In consideration of the results, detailed suggestions for Turkey have been proposed. The research results are expected to be used as a roadmap for coordinating the stakeholders of bioeconomy and integrating Turkish Research Areas into European Research Areas.

European Union's strategy on endocrine disrupting chemicals and the current position of Slovenia.

PubMed

Perharič, Lucija; Fatur, Tanja; Drofenik, Jernej

2016-06-01

In view of the European Union regulations 1107/2009 and 528/2012, which say that basic substances in plant protection and biocidal products marketed in the European Union (EU) should not have an inherent capacity to cause endocrine disruption, an initiative was started to define scientific criteria for the identification of endocrine disruptors (EDs). The objectives of the EU strategy on EDs are to protect human health and the environment, to assure the functioning of the market, and to provide clear and coherent criteria for the identification of EDs that could have broad application in the EU legislation. Policy issues were to be addressed by the Ad-hoc group of Commission Services, EU Agencies and Member States established in 2010, whereas the scientific issues were to be addressed by the Endocrine Disruptors Expert Advisory Group (ED EAG), established in 2011. The ED EAG adopted the 2002 World Health Organization (WHO) definition of endocrine disruptor and agreed that for its identification it is necessary to produce convincing evidence of a biologically plausible causal link between an adverse effect and endocrine disrupting mode of action. In 2014, the European Commission proposed four ED identification criteria options and three regulatory options, which are now being assessed for socio-economic, environmental, and health impact. Slovenia supports the establishing of identification criteria and favours option 4, according to which ED identification should be based on the WHO definition with the addition of potency as an element of hazard characterisation. As for regulatory options, Slovenia favours the risk-based rather than hazard-based regulation.

Water-soluble Schiff base-actinyl complexes and their effect on the solvent extraction of f-elements

DOE PAGES

Hawkins, Cory A.; Bustillos, Christian G.; May, Iain; ...

2016-09-07

Conventional solvent extraction of selected f-element cations by bis(2-ethylhexyl)phosphoric acid (HDEHP) yields increased extraction from aqueous to organic solution along the series Np(V) < Cm(III) < Eu(III) < U(VI), with distribution ratios all within two orders of magnitude. However, in the presence of the water-soluble tetradentate Schiff base (N,N'-bis(5-sulfonatosalicylidene)-ethylenediamine or H 2salenSO 3), selective complexation of the two actinyl cations (Np(V) and U(VI)) resulted in an extraction order of Np(V) < U(VI) << Eu(III) < Cm(III). The extraction of neither Cm(III) or Eu(III) by HDEHP are significantly impacted by the presence of the aqueous phase Schiff base. Despite observed hydrolyticmore » decomposition of H 2salenSO 3 in aqueous solutions, the calculated high conditional stability constant (β 11 = 26) for the complex [UO 2(salenSO 3)] 2- demonstrates its capacity for aqueous hold-back of U(VI). UV-visible-NIR spectroscopy of solutions prepared with a Np(VI) stock and H 2salenSO 3 suggest that reduction of Np(VI) to Np(V) by the ligand was rapid, resulting in a pentavalent Np complex that was substantially retained in the aqueous phase. Lastly, results from 1H NMR of aqueous solutions of H 2salenSO 3 with U(VI) and La(III), Eu(III), and Lu(III) provides additional evidence that the ligand readily chelates U(VI), but has only weak interactions with trivalent lanthanide ions.« less

Naval War College Review. Volume 64, Number 1, Winter 2011

DTIC Science & Technology

2011-01-01

2010, a Chinese delegation headed by Major General Li Ning, the defense counselor for the Chinese mission to the European Union , visited the...headquarters of European Union Naval Force (EU NAVFOR) Somalia in Djibouti.52 Djibouti would be an excellent choice as a place for the PLAN, and it should...France’s Base Aérienne 188 is home to the headquarters of EU NAVFOR Somalia/Operation ATALANTA, the European Union naval force tasked with

The Transformation from Defence Procurement to Defence Acquisition - Opportunities for New Forms of Analytical Support

DTIC Science & Technology

2010-04-01

Exchanges of Services ( ATARES ); Strategic Airlift Interim Solution (SALIS); Strategic Airlift Capability (SAC); the European Air Transport Fleet (EATF... ATARES is a TA, established in order to facilitate the exchange of military capabilities based on equivalent flying hours with Lockheed C-130 Hercules...initiatives such as NATO PfP, EU BG, MNE, NAMSA, MCCE, ATARES , SALIS, and SAC. The participation in the EU BG concept was as one of the contributors

Tuning the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions based on colorimetric principle

NASA Astrophysics Data System (ADS)

Zhang, Aiqin; Yang, Yamin; Zhai, Guangmei; Jia, Husheng; Xu, Bingshe

2016-02-01

In this work, a method of tuning the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions based on colorimetric principle was proposed. The technological route from coordination to copolymerization was employed to obtain the white light macromolecular phosphor. The three primary color monomers have been synthesized and their Commission Internationale de L'Eclairage (CIE) coordinates are respectively (0.540, 0.314), (0.231, 0.463), and (0.161, 0.054). The molar feed ratios of the three primary color monomers were calculated from the CIE coordinates based on colorimetric principle. Serial copolymers have been synthesized by free radical copolymerization of the three primary color monomers and methyl methacrylate. The quantum efficiency of the copolymers was higher than that of the complex monomers. The complexes were directly boned to the polymer chain, in which the energy transfer was reduced significantly compared to the doped-polymers. The experimental values of copolymers' CIE coordinates were located in the white light region in good agreement with theoretical values. The results indicate that the chromaticity of the emission color of the copolymers containing Eu(III), Tb(III), Be(II) ions could be tuned by theoretical calculation based on colorimetric principle.

Can Croatia Join Europe as Competitive Knowledge-based Society by 2010?

PubMed Central

Petrovečki, Mladen; Paar, Vladimir; Primorac, Dragan

2006-01-01

The 21st century has brought important changes in the paradigms of economic development, one of them being a shift toward recognizing knowledge and information as the most important factors of today. The European Union (EU) has been working hard to become the most competitive knowledge-based society in the world, and Croatia, an EU candidate country, has been faced with a similar task. To establish itself as one of the best knowledge-based country in the Eastern European region over the next four years, Croatia realized it has to create an education and science system correspondent with European standards and sensitive to labor market needs. For that purpose, the Croatian Ministry of Science, Education, and Sports (MSES) has created and started implementing a complex strategy, consisting of the following key components: the reform of education system in accordance with the Bologna Declaration; stimulation of scientific production by supporting national and international research projects; reversing the “brain drain” into “brain gain” and strengthening the links between science and technology; and informatization of the whole education and science system. In this comprehensive report, we describe the implementation of these measures, whose coordination with the EU goals presents a challenge, as well as an opportunity for Croatia to become a knowledge-based society by 2010. PMID:17167853

Visible and NIR photoluminescence properties of a series of novel lanthanide-organic coordination polymers based on hydroxyquinoline-carboxylate ligands.

PubMed

Gai, Yan-Li; Xiong, Ke-Cai; Chen, Lian; Bu, Yang; Li, Xing-Jun; Jiang, Fei-Long; Hong, Mao-Chun

2012-12-17

A series of novel two-dimensional (2D) lanthanide coordination polymers with 4-hydroxyquinoline-2-carboxylate (H(2)hqc) ligands, [Ln(Hhqc)(3)(H(2)O)](n)·3nH(2)O (Ln = Eu (1), Tb (2), Sm (3), Nd (4), and Gd (5)) and [Ln(Hhqc)(ox)(H(2)O)(2)](n) (Ln = Eu (6), Tb (7), Sm (8), Tm (9), Dy (10), Nd (11), Yb (12), and Gd (13); H(2)ox = oxalic acid), have been synthesized under hydrothermal conditions. Complexes 1-5 are isomorphous, which can be described as a two-dimensional (2D) hxl/Shubnikov network based on Ln(2)(CO(2))(4) paddle-wheel units, and the isomorphous complexes 6-13 feature a 2D decker layer architecture constructed by Ln-ox infinite chains cross-linked alternatively by bridging Hhqc(-) ligands. The room-temperature photoluminescence spectra of complexes Eu(III) (1 and 6), Tb(III) (2 and 7), and Sm(III) (3 and 8) exhibit strong characteristic emissions in the visible region, whereas Nd(III) (4 and 11) and Yb(III) (12) complexes display NIR luminescence upon irradiation at the ligand band. Moreover, the triplet state of H(2)hqc matches well with the emission level of Eu(III), Tb(III), and Sm(III) ions, which allows the preparation of new optical materials with enhanced luminescence properties.

Impact of Financial Liberalization on Banking Sectors Performance from Central and Eastern European Countries

PubMed Central

Andries, Alin Marius; Capraru, Bogdan

2013-01-01

In this paper we analyse the impact of financial liberalization and reforms on the banking performance in 17 countries from CEE for the period 2004–2008 using a two-stage empirical model that involves estimating bank performance in the first stage and assessing its determinants in the second one. From our analysis it results that banks from CEE countries with higher level of liberalization and openness are able to increase cost efficiency and eventually to offer cheaper services to clients. Banks from non-member EU countries are less cost efficient but experienced much higher total productivity growth level, and large sized banks are much more cost efficient than medium and small banks, while small sized banks show the highest growth in terms of productivity. PMID:23555745

Impact of financial liberalization on banking sectors performance from central and eastern European countries.

PubMed

Andries, Alin Marius; Capraru, Bogdan

2013-01-01

In this paper we analyse the impact of financial liberalization and reforms on the banking performance in 17 countries from CEE for the period 2004-2008 using a two-stage empirical model that involves estimating bank performance in the first stage and assessing its determinants in the second one. From our analysis it results that banks from CEE countries with higher level of liberalization and openness are able to increase cost efficiency and eventually to offer cheaper services to clients. Banks from non-member EU countries are less cost efficient but experienced much higher total productivity growth level, and large sized banks are much more cost efficient than medium and small banks, while small sized banks show the highest growth in terms of productivity.

EUGÈNE'HOM: a generic similarity-based gene finder using multiple homologous sequences

PubMed Central

Foissac, Sylvain; Bardou, Philippe; Moisan, Annick; Cros, Marie-Josée; Schiex, Thomas

2003-01-01

EUGÈNE'HOM is a gene prediction software for eukaryotic organisms based on comparative analysis. EUGÈNE'HOM is able to take into account multiple homologous sequences from more or less closely related organisms. It integrates the results of TBLASTX analysis, splice site and start codon prediction and a robust coding/non-coding probabilistic model which allows EUGÈNE'HOM to handle sequences from a variety of organisms. The current target of EUGÈNE'HOM is plant sequences. The EUGÈNE'HOM web site is available at http://genopole.toulouse.inra.fr/bioinfo/eugene/EuGeneHom/cgi-bin/EuGeneHom.pl. PMID:12824408

Controlled synthesis of Eu 2+ and Eu 3+ doped ZnS quantum dots and their photovoltaic and magnetic properties

DOE PAGES

Horoz, Sabit; Yakami, Baichhabi; Poudyal, Uma; ...

2016-04-27

Eu-doped ZnS quantum dots (QDs) have been synthesized by wet-chemical method and found to form in zinc blende (cubic) structure. Both Eu 2+ and Eu 3+ doped ZnS can be controllably synthesized. The Eu 2+ doped ZnS QDs show broad photoluminescence emission peak around 512 nm, which is from the Eu2+ intra-ion transition of 4f 6d1 – 4f 7, while the Eu 3+ doped samples exhibit narrow emission lines characteristic of transitions between the 4f levels. The investigation of the magnetic properties shows that the Eu 3+ doped samples exhibit signs of ferromagnetism, on the other hand, Eu 2+ dopedmore » samples are paramagnetic of Curie-Weiss type. The incident photon to electron conversion efficiency is increased with the Eu doping, which suggests the QD solar cell efficiency can be enhanced by Eu doping due to widened absorption windows. This is an attractive approach to utilize benign and environmentally friendly wide band gap ZnS QDs in solar cell technology.« less

Structural and spectroscopic investigation of new luminescent hybrid materials based on calix[4]arene-tetracarboxylate and Ln3+ ions (Ln = Gd, Tb or Eu)

NASA Astrophysics Data System (ADS)

Viana, R. S.; Oliveira, C. A. F.; Chojnacki, J.; Barros, B. S.; Alves-Jr, S.; Kulesza, J.

2017-07-01

Lanthanide-calixarene hybrid materials are of particular interest due to the combination of the interesting properties of the ligand cavity-like structure and the luminescent features of lanthanides. The aim of this study was to synthesize and investigate the photophysical properties of Eu3+, Tb3+ and Gd3+ hybrids based on calix[4]arene-tetracarboxylate. The preparation of two structurally different Tb3+ compounds (calix-TA-SC-Tb and calix-TA-Tb) was dictated by the ligand to metal molar ratio and the synthesis time. Analysis of calix-TA-SC-Tb monocrystals revealed the formation of a mononuclear complex of C2 symmetry containing Tb3+ coordinated by four calixarene ionized groups and formate anion encapsulated within the upper cavity. Syntheses of other hybrids failed in producing high-quality crystals and the structures could not be solved. The solid-state luminescent properties of hybrids were evaluated, and the structure/property relationship was investigated. Based on the emission and excitation spectra, the energy diagrams for calix-TA-Eu, calix-TA-Tb and calix-TA-Gd were proposed.

Generic oncology drugs: are they all safe?

PubMed

Yang, Y Tony; Nagai, Sumimasa; Chen, Brian K; Qureshi, Zaina P; Lebby, Akida A; Kessler, Samuel; Georgantopoulos, Peter; Raisch, Dennis W; Sartor, Oliver; Hermanson, Terhi; Kane, Robert C; Hrushesky, William J; Riente, Joshua J; Norris, LeAnn B; Bobolts, Laura R; Armitage, James O; Bennett, Charles L

2016-11-01

Although the availability of generic oncology drugs allows access to contemporary care and reduces costs, there is international variability in the safety of this class of drugs. In this Series paper, we review clinical, policy, safety, and regulatory considerations for generic oncology drugs focusing on the USA, Canada, the European Union (EU), Japan, China, and India. Safety information about generic formulations is reviewed from one agent in each class, for heavy metal drugs (cisplatin), targeted agents (imatinib), and cytotoxic agents (docetaxel). We also review regulatory reports from Japan and the USA, countries with the largest pharmaceutical expenditures. Empirical studies did not identify safety concerns in the USA, Canada, the EU, and Japan, where regulations and enforcement are strong. Although manufacturing problems for generic pharmaceuticals exist in India, where 40% of all generic pharmaceuticals used in the USA are manufactured, increased inspections and communication by the US Food and Drug Administration are occurring, facilitating oversight and enforcement. No safety outbreaks among generic oncology drugs were reported in developed countries. For developing countries, oversight is less intensive, and concerns around drug safety still exist. Regulatory agencies should collaboratively develop procedures to monitor the production, shipment, storage, and post-marketing safety of generic oncology drugs. Regulatory agencies for each country should also aim towards identical definitions of bioequivalence, the cornerstone of regulatory approval. Copyright © 2016 Elsevier Ltd. All rights reserved.

Measuring performance in off-patent drug markets: a methodological framework and empirical evidence from twelve EU Member States.

PubMed

Kanavos, Panos

2014-11-01

This paper develops a methodological framework to help evaluate the performance of generic pharmaceutical policies post-patent expiry or after loss of exclusivity in non-tendering settings, comprising five indicators (generic availability, time delay to and speed of generic entry, number of generic competitors, price developments, and generic volume share evolution) and proposes a series of metrics to evaluate performance. The paper subsequently tests this framework across twelve EU Member States (MS) by using IMS data on 101 patent expired molecules over the 1998-2010 period. Results indicate that significant variation exists in generic market entry, price competition and generic penetration across the study countries. Size of a geographical market is not a predictor of generic market entry intensity or price decline. Regardless of geographic or product market size, many off patent molecules lack generic competitors two years after loss of exclusivity. The ranges in each of the five proposed indicators suggest, first, that there are numerous factors--including institutional ones--contributing to the success of generic entry, price decline and market penetration and, second, MS should seek a combination of supply and demand-side policies in order to maximise cost-savings from generics. Overall, there seems to be considerable potential for faster generic entry, uptake and greater generic competition, particularly for molecules at the lower end of the market. Copyright © 2014. Published by Elsevier Ireland Ltd.

'Know before you go': information-seeking behaviour of German patients receiving health services abroad in light of the provisions of Directive 2011/24/EU.

PubMed

Panteli, Dimitra; Wagner, Caroline; Verheyen, Frank; Busse, Reinhard

2015-07-01

While Directive 2011/24/EU on cross-border patient mobility makes specific provisions in relation to information availability and accessibility, little empirical evidence exists to guide best practice. This paper explores the information-seeking behaviour of German patients who received planned care abroad. A postal survey among German patients treated in other European countries was carried out by Techniker Krankenkasse, a major German sickness fund. The influence of certain predictors on whether patients informed themselves before travelling for care was investigated using multiple logistic regression. Types and sources of information were analysed using descriptive statistics. Information activity was contingent on patients' level of education, type of service, regularity of treatment abroad and awareness of entitlement to cross-border services. Respondents most frequently enquired about elements of reimbursement, entitlement to services and cost-saving, and consulted their sickness fund for information. Differences in both content and medium of choice were observed between patient groups. A structured and inclusive approach to information provision should be adopted. National Contact Points should collaborate with a range of stakeholders, who will vary depending on the health care system; however, patient organizations, health professionals and third-party payers should always be represented. Dynamically monitoring cross-border movements can help determine the range, medium and language of relevant information. © The Author(s) 2015.

EU ambition to build the world's leading bioeconomy-Uncertain times demand innovative and sustainable solutions.

PubMed

Bell, John; Paula, Lino; Dodd, Thomas; Németh, Szilvia; Nanou, Christina; Mega, Voula; Campos, Paula

2018-01-25

This article outlines the current context and the development of the European Bioeconomy Strategy. It analyses the current situation, challenges and needs for EU action and concludes with the next steps that the European Commission will undertake to review and update the Bioeconomy Strategy. Bioeconomy offers great opportunities to realising a competitive, circular and sustainable economy with a sound industrial base that is less dependent on fossil carbon. A sustainable bioeconomy also contributes to climate change mitigation, with oceans, forests and soils being major carbon sinks and fostering negative CO 2 emissions. The EU has invested significantly in research and innovation in this field and the European Commission is committed to lead on European bioeconomy strategy. Copyright © 2017 Elsevier B.V. All rights reserved.

Variation of the temperature coefficient of collapse field in bismuth-based bubble garnets

NASA Technical Reports Server (NTRS)

Fratello, V. J.; Pierce, R. D.; Brandle, C. D.

1985-01-01

An approximation to the collapse-field formula is used to show its dependence on magnetization and wall energy and the effect of additions of Gd, Sm, and Eu on 1-micron Bi:YIG bubble materials. The collapse field, magnetization, and wall energy are fitted to quadratic functions of temperature from -50 to 150 C. It is shown that the addition of the various classes of rare earths reduces the temperature derivative of the collapse field in Bi:YIG. Gd influences the collapse field through the magnetization, Sm affects it through the domain wall energy, and Eu does both. The singular magnetic properties of Eu result in the most nearly constant temperature dependence of the collapse field and the best match to a barium-ferrite bias magnite.

Effects of Eu doping and O vacancy on the magnetic and optical properties of ZnO

NASA Astrophysics Data System (ADS)

Ling-Feng, Qu; Qing-Yu, Hou; Xiao-Fang, Jia; Zhen-Chao, Xu; Chun-Wang, Zhao

2018-02-01

We calculated the electronic structure and optical properties of Eu mono-doped ZnO systems with or without O vacancy. We also determined the relative energy of ferromagnetic and antiferromagnetic orders of Eu-double-doped ZnO systems. The double-doped systems possess high Curie temperature and achieve room temperature ferromagnetism. The magnetism in the Eu mono-doped system without O vacancy is caused by the -Eu3+-O2--Eu3+- bound magnetopolaron (BMP) model. The magnetism of Eu mono-doped ZnO systems with O vacancy is more stable than that without O vacancy, and such magnetism is attributed to the -Eu3+-VO++-Eu3+- BMP model. The absorption spectrum for mono-doped systems is red shifted, and this finding confirms that Eu-mono-doped ZnO is a candidate photocatalyst for various applications. Therefore, Eu-double-doped ZnO can be practically used as an unambiguous diluted magnetic semiconductor.

Luminescence and Site Occupancy of Eu2+ in Ba2 Ca(BO3)2

NASA Astrophysics Data System (ADS)

Li, Pan-Lai; Wang, Zhi-Jun; Yang, Zhi-Ping; Guo, Qing-Lin

2011-01-01

A green phosphor Ba2Ca(BO3)2:Eu2+ was synthesized by a high temperature solid-state reaction method under a reductive atmosphere. The luminescence and site occupancy of Eu2+ in Ba2Ca(BO3)2 are investigated. Ba2Ca(BO3)2:Eu2+ shows one green band (537 nm) under 400 nm near ultraviolet excitation which is suitable for UV LED. Ca2+ and Ba2+ ions in Ba2Ca(BO3)2 are replaced by Eu2+ ions, the Ba2Ca(BO3)2:Eu2+ shows a dissymmetrical emission band. The influence of Eu2+ doping concentrations on the emission intensity of Ba2Ca(BO3)2:Eu2+ is studied. It is found that the emission intensity is influenced by the Eu2+ concentration and reaches the maximum value at 2% Eu2+. According to the Dexter theory, the concentration quenching mechanisms of Eu2+ in Ba2Ca(BO3)2 are the d-dinteraction.

Fano Resonance of Eu2+ and Eu3+ in (Eu,Gd)Te MBE Layers