Magnetism in the p-type Monolayer II-VI semiconductors SrS and SrSe

Science.gov (United States)

Lin, Heng-Fu; Lau, Woon-Ming; Zhao, Jijun

2017-01-01

Using density functional theory calculations, we study the electronic and magnetic properties of the p-type monolayer II-VI semiconductors SrX (X = S,Se). The pristine SrS and SrSe monolayers are large band gap semiconductor with a very flat band in the top valence band. Upon injecting hole uniformly, ferromagnetism emerges in those system in a large range of hole density. By varying hole density, the systems also show complicated phases transition among nonmagnetic semiconductor, half metal, magnetic semiconductor, and nonmagnetic metal. Furthermore, after introducing p-type dopants in SrS and SrSe via substitutionary inserting P (or As) dopants at the S (or Se) sites, local magnetic moments are formed around the substitutional sites. The local magnetic moments are stable with the ferromagnetic order with appreciable Curie temperature. The ferromagnetism originates from the instability of the electronic states in SrS and SrSe with the large density of states at the valence band edge, which demonstrates a useful strategy for realizing the ferromagnetism in the two dimensional semiconductors. PMID:28378761

Surface Renewal Application for Estimating Evapotranspiration: A Review

Directory of Open Access Journals (Sweden)

Yongguang Hu

2018-01-01

Full Text Available The estimation of evapotranspiration (ET is essential for meteorological modeling of surface exchange processes, as well as for the agricultural practice of irrigation management. Hitherto, a number of methods for estimation of ET at different temporal scales and climatic conditions are constantly under investigation and improvement. One of these methods is surface renewal (SR. Therefore, the premise of this review is to present recent developments and applications of SR for ET measurements. The SR method is based on estimating the turbulent exchange of sensible heat flux between plant canopy and atmosphere caused by the instantaneous replacement of air parcels in contact with the surface. Additional measurements of net radiation and soil heat flux facilitate extracting ET using the shortened energy balance equation. The challenge, however, is the calibration of SR results against direct sensible heat flux measurements. For the classical SR method, only air temperature measured at high frequency is required. In addition, a new model suggests that the SR method could be exempted from calibration by measuring additional micrometeorological variables. However, further improvement of the SR method is required to provide improved results in the future.

Renewal processes with costs and rewards

NARCIS (Netherlands)

Vlasiou, M.; Cochran, J.J.; Cox, L.A.; Keskinocak, P.; Kharoufeh, J.P.; Smith, J.C.

2011-01-01

We review the theory of renewal reward processes, which describes renewal processes that have some cost or reward associated with each cycle. We present a new simplified proof of the renewal reward theorem that mimics the proof of the Elementary Renewal Theorem and avoids the technicalities in the

Surface renewal method for estimating sensible heat flux | Mengistu ...

African Journals Online (AJOL)

There are 2 SR analysis approaches: the ideal SR analysis approach which ... canopy structure and stability conditions since it depends on the capability of the ... A combination approach using SR and either similarity theory, that requires ...

Electronic structure and optical properties of Sr{sub 2}SnO{sub 4} studied with FP-LAPW method in density functional theory

Energy Technology Data Exchange (ETDEWEB)

Prijamboedi, B., E-mail: boedi@chem.itb.ac.id; Umar, S.; Failamani, F. [Inorganic and Physical Chemistry Research Division, Faculty of Mathematics and Natural Sciences, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132 (Indonesia)

2015-04-16

Oxide material of Sr{sub 2}SnO{sub 4}, when it is doped with Ti becomes a phosphor material that can emit intense blue light at room temperature. It is important to study the electronic structure of this material in order to determine the optical processes that occur in Ti-doped Sr{sub 2}SnO{sub 4}. Electronic structure and optical properties of Sr{sub 2}SnO{sub 4} is studied using density functional theory framework with full potential linearized augmented plane waves plus local orbitals (FP-LAPW+lo) method. We use modified Becke-Johnson (mBJ) exchange-correlation potential to calculate the energy gap. Our calculation showed that Sr{sub 2}SnO{sub 4} has indirect band gap with band gap energy of around 4.2 eV. The experimental absorption spectra of Sr{sub 2}SnO{sub 4} indicated that this oxide has band gap of around 4.6 eV and it is closer to the results given by mBJ exchange-correlation potential. We also studied other optical properties of Sr{sub 2}SnO{sub 4} and it is found in agreement with the experimental results.

Ab initio investigations of the strontium gallium nitride ternaries Sr 3GaN3 and Sr6GaN5: Promising materials for optoelectronic

KAUST Repository

Goumri-Said, Souraya

2013-05-31

Sr3GaN3 and Sr6GaN5 could be promising potential materials for applications in the microelectronics, optoelectronics and coating materials areas of research. We studied in detail their structural, elastic, electronic, optical as well as the vibrational properties, by means of density functional theory framework. Both of these ternaries are semiconductors, where Sr3GaN3 exhibits a small indirect gap whereas Sr6GaN5 has a large direct gap. Indeed, their optical properties are reported for radiation up to 40 eV. Charge densities contours, Hirshfeld and Mulliken populations, are reported to investigate the role of each element in the bonding. From the mechanical properties calculation, it is found that Sr6GaN5 is harder than Sr3GaN3, and the latter is more anisotropic than the former. The phonon dispersion relation, density of phonon states and the vibrational stability are reported from the density functional perturbation theory calculations. © 2013 IOP Publishing Ltd.

Electronic structure of α-SrB4O7: experiment and theory

International Nuclear Information System (INIS)

Atuchin, V V; Kesler, V G; Zaitsev, A I; Molokeev, M S; Aleksandrovsky, A S; Kuzubov, A A; Ignatova, N Y

2013-01-01

The investigation of valence band structure and electronic parameters of constituent element core levels of α-SrB 4 O 7 has been carried out with x-ray photoemission spectroscopy. Optical-quality crystal α-SrB 4 O 7 has been grown by the Czochralski method. Detailed photoemission spectra of the element core levels have been recorded from the powder sample under excitation by nonmonochromatic Al Kα radiation (1486.6 eV). The band structure of α-SrB 4 O 7 has been calculated by ab initio methods and compared to XPS measurements. It has been found that the band structure of α-SrB 4 O 7 is weakly dependent on the Sr-related states. (paper)

Surface modeling and chemical solution deposition of SrO(SrTiO3)n Ruddlesden-Popper phases

International Nuclear Information System (INIS)

Zschornak, M.; Gemming, S.; Gutmann, E.; Weissbach, T.; Stoecker, H.; Leisegang, T.; Riedl, T.; Traenkner, M.; Gemming, T.; Meyer, D.C.

2010-01-01

Strontium titanate (STO) is a preferred substrate material for functional oxide growth, whose surface properties can be adjusted through the presence of Ruddlesden-Popper (RP) phases. Here, density functional theory (DFT) is used to model the (1 0 0) and (0 0 1) surfaces of SrO(SrTiO 3 ) n RP phases. Relaxed surface structures, electronic properties and stability relations have been determined. In contrast to pure STO, the near-surface SrO-OSr stacking fault can be employed to control surface roughness by adjusting SrO and TiO 2 surface rumpling, to stabilize SrO termination in an SrO-rich surrounding or to increase the band gap in the case of TiO 2 termination. RP thin films have been epitaxially grown on (0 0 1) STO substrates by chemical solution deposition. In agreement with DFT results, the fraction of particular RP phases n = 1-3 changes with varying heating rate and molar ratio Sr:Ti. This is discussed in terms of bulk formation energy.

Wind, hydro or mixed renewable energy source: Preference for electricity products when the share of renewable energy increases

International Nuclear Information System (INIS)

Yang, Yingkui; Solgaard, Hans Stubbe; Haider, Wolfgang

2016-01-01

While the share of renewable energy, especially wind power, increases in the energy mix, the risk of temporary energy shortage increases as well. Thus, it is important to understand consumers' preference for the renewable energy towards the continuous growing renewable energy society. We use a discrete choice experiment to infer consumers' preferences when the share of renewable energy increases. The study results indicate that consumers are generally willing to pay extra for an increasing share of renewable energy, but the renewable energy should come from a mixture of renewable energy sources. We also found that consumers prefer to trade with their current supplier rather than another well-known supplier. This study contributes to the energy portfolio theories and the theory of energy diversification in a consumer perspective. The managerial implications of this study are also discussed. - Highlights: • This paper investigates consumer preference for electricity when the share of renewable energy increases in the energy mix. • A total of 7084 choice sets were completed in the survey. • Consumer prefers a high percentage of mixed renewable energy at an affordable price level when the share of renewable increases. • Current electricity supplier was found to be the most favorable supplier for consumers. • Results had implications on energy regulators/policy makers, electricity retailers and renewable energy investors.

Renewal Processes and Repairable Systems

NARCIS (Netherlands)

2003-01-01

In this thesis we discuss the following topics: 1. Renewal reward processes The marginal distributions of renewal reward processes and its version, which we call in this thesis instantaneous reward processes, are derived. Our approach is based on the theory of point processes, especially Poisson

Moment convergence in renewal theory

NARCIS (Netherlands)

Iksanov, A.; Marynych, A.; Meiners, M.

2012-01-01

Let ¿1, ¿2, . . . be independent copies of a positive random variable ¿, and let Sk := ¿ 1 + . . . + ¿ k, k ¿ N0. Define N(t) := #{k ¿ N0 : Sk= t}. (N(t))t=0 is a renewal counting process. It is known that if ¿ is in the domain of attraction of a stable law of index a ¿ (1, 2], then N(t), suitably

Renewable Energy in European Regions

NARCIS (Netherlands)

Krozer, Yoram

2012-01-01

The regional dynamics of energy innovation, in particular the shift from fossil fuels to renewable energy in the EU, is discussed within the framework of neo-Schumpeterian theory. The EU’s 4.2% average annual growth in renewable energy production in the last decade has been accompanied by diverging

Strategy for the expansion of renewable energies. An investigation of the pricing strategy of the Renewable Energy Law from the viewpoint of an evolutionary cybernetic theory of economic policy; Die Strategie des Ausbaus erneuerbarer Energien. Eine Untersuchung der Preissetzungsstrategie des EEGs aus Sicht einer evolutorisch-kybernetischen Theorie der Wirtschaftspolitik

Energy Technology Data Exchange (ETDEWEB)

Schlueter, Fabian

2015-11-01

This publication reports on how the steadily increasing costs caused by the Renewable Energy Law (EEG) have brought the German strategy for the expansion of renewable energies under criticism. According to theories of regulatory economic policy, which state that politico-economic incentives of this kind must necessarily result in an inefficient allocation of scarce resources, this cost increase can be interpreted as a direct consequence of the price intervention. The present publication takes a critical stance on this viewpoint, developing for its purpose a new position on regulatory policy referred to as the evolutionary cybernetic theory of economic policy. It starts out from the works of F.A. von Hayek, which it then takes a significant step further however. The author argues that price interventions can be meaningful strategies of economic policy as long as they are aimed at a temporary initiation of market development towards sustainability and efficiency. Based on this model conception of a shrewd pricing strategy the publication undertakes an analysis from the perspective of regulatory policy of the German subsidisation of renewable energies. In the process it not only reveals errors in design of the EEG but also makes a proposal for an amendment that could be effective in cutting through the present price dynamics. In presenting its recommendation of a self-steering expansion policy the publication not only contributes to the further development of an evolutionary cybernetic theory of economic policy but addresses the urgent problem of how to wisely use regulatory policy to create pricing strategies which serve the expansion of renewable energies.

Renewable Resources, Capital Accumulation, and Economic Growth

OpenAIRE

Wei-Bin Zhang

2011-01-01

This paper proposes a dynamic economic model with physical capital and renewable resources. Different from most of the neoclassical growth models with renewable resources which are based on microeconomic foundation and neglect physical capital accumulation, this study proposes a growth model with dynamics of renewable resources and physical capital accumulation. The model is a synthesis of the neoclassical growth theory and the traditional dynamic models of renewable resources with an alterna...

Determining of the Optimal Device Lifetime using Mathematical Renewal Models

Directory of Open Access Journals (Sweden)

Knežo Dušan

2016-05-01

Full Text Available Paper deals with the operations and equipment of the machine in the process of organizing production. During operation machines require maintenance and repairs, while in case of failure or machine wears it is necessary to replace them with new ones. For the process of replacement of old machines with new ones the term renewal is used. Qualitative aspects of the renewal process observe renewal theory, which is mainly based on the theory of probability and mathematical statistics. Devices lifetimes are closely related to the renewal of the devices. Presented article is focused on mathematical deduction of mathematical renewal models and determining optimal lifetime of the devices from the aspect of expenditures on renewal process.

Test theories of special relativity: a general critique

International Nuclear Information System (INIS)

Maciel, A.K.A.; Tiomno, J.

1988-01-01

Absolute Spacetime Theories conceived for the purpose of testing Special Relativity (SR) are reviewed. It is found that most theories proposed were in fact SR in different coordinate systems, since in general no specific SR violations were introduced. Models based on possible SR violating mechanisms are considered. Misconceptions in recently published papers are examined. (author) [pt

Structural and electronic properties of SrAl{sub 2}O{sub 4}:Eu{sup 2+} from density functional theory calculations

Energy Technology Data Exchange (ETDEWEB)

Nazarov, M. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Institute of Applied Physics, Academiei Street 5, Chisinau MD-2028 (Moldova, Republic of); Brik, M.G., E-mail: brik@fi.tartu.ee [Institute of Physics, University of Tartu, Riia 142, Tartu 51014 (Estonia); Spassky, D. [Institute of Physics, University of Tartu, Riia 142, Tartu 51014 (Estonia); Skobeltsyn Institute of Nuclear Physics, M.V. Lomonosov Moscow State University, 119991 Moscow (Russian Federation); Tsukerblat, B. [Department of Chemistry, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Nor Nazida, A. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang (Malaysia); Faculty of Art and Design, Universiti Teknologi MARA (Perak), Seri Iskandar, 32610 Bandar Baru Seri Iskandar, Perak (Malaysia); Ahmad-Fauzi, M.N. [School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Engineering Campus, 14300 Nibong Tebal, Pulau Pinang (Malaysia)

2013-10-05

Highlights: •Persistent phosphor SrAl{sub 2}O{sub 4}:Eu{sup 2+} was synthesized and studied. •Ab initio calculations of its electronic properties were performed. •Lowest position of the Eu 4f states in the band gap was determined. •Position of the Eu 4f states agrees with the charge transfer transition. -- Abstract: A stoichiometric micro-sized powder SrAl{sub 2}O{sub 4}:Eu{sup 2+} was synthesized by traditional solid state reaction at 1250 °C. Low-temperature spectroscopic measurements revealed two luminescence bands at 450 nm and 512 nm; their origin was discussed. Theoretical calculations of the structural and optical properties of SrAl{sub 2}O{sub 4}:Eu{sup 2+} in the framework of the density functional theory (DFT) were carried out; the obtained results were compared with the corresponding experimental data. For the first time, the position of the lowest 4f states of Eu in the host’s band gap was calculated for both available Sr positions to be at about 4.5–5 eV above the top of the valence band. Reliability of this result is confirmed by good agreement with the experimental value of the O(2p)–Eu(4f) charge transfer energy, which is equal to about 4.9 eV.

K-Ca and Rb-Sr Dating of Lunar Granite 14321 Revisited

Science.gov (United States)

Simon, Justin I.; Shih, C.-Y.; Nyquist, L. E.

2011-01-01

K-Ca and Rb-Sr age determinations were made for a bulk feldspar-rich portion of an Apollo rock fragment of the pristine lunar granite clast (14321,1062), an acid-leached split of the sample, and the leachate. K-Ca and Rb-Sr data were also obtained for a whole rock sample of Apollo ferroan anorthosite (FAN, 15415). The recent detection [1] of widespread intermediate composition plagioclase indicates that the generation of a diversity of evolved lunar magmas maybe more common and therefore more important to our understanding of crust formation than previously believed. Our new data strengthen the K-Ca and Rb-Sr internal isochrons of the well-studied Apollo sample 14321 [2], which along with a renewed effort to study evolved lunar magmas will provide an improved understanding of the petrogenetic history of evolved rocks on the Moon.

Subsidies for renewable energy?

International Nuclear Information System (INIS)

Skytte, K.; Grenaa Jensen, S.; Morthorst, P.E.; Olsen, O.J.

2004-01-01

Ambitious Danish and European energy and environment objectives make a point of using renewable energy sources in the electricity supply. Denmark has been leading country in successful development and commercialization of wind turbines and is as yet one of the leading manufacturers of the world. Danish governments have successfully invested a lot in this development. Other countries have spent more money without achieving a similar success. The questions are why things have gone so well in Denmark and if the Danish success can be repeated for other renewable energy technologies. The starting point of this book is that a political decision on subsidizing the developmental process of a specific technology not in itself guarantees that the technology will turn out reliable and efficient enough to compete successfully in a liberalized electricity market. An understanding of this development is necessary in order to affect a technological development. This book goes through the development of different renewable energy technologies and two theories used for discussing the technological development: experience curves and innovation theory. Based on the discussions and a description of causal relations, an analytical model for different phases of renewable energy technologies' developmental progress and technological life cycle is made. The model is used for evaluating the subsidies for chosen renewable technologies in Denmark. With wind energy as example an analysis of what went well or badly, what might be done and which actions might be efficient is made. (BA)

Structural, electronic, optical and thermoelectric investigations of antiperovskites A3SnO (A = Ca, Sr, Ba) using density functional theory

Science.gov (United States)

Hassan, M.; Shahid, A.; Mahmood, Q.

2018-02-01

Density functional theory study of the structural, electrical, optical and thermoelectric behaviors of very less investigated anti-perovskites A3SnO (A = Ca, Sr, Ba) is performed with FP-LAPW technique. The A3SnO exhibit narrow direct band gap, in contrast to the wide indirect band gap of the respective perovskites. Hence, indirect to direct band gap transformation can be realized by the structural transition from perovskite to anti-perovskite. The p-p hybridization between A and O states result in the covalent bonding. The transparency and maximum reflectivity to the certain energies, and the verification of the Penn's model indicate potential optical device applications. Thermoelectric behaviors computed within 200-800 K depict that Ca3SnO exhibits good thermoelectric performance than Ba3SnO and Sr3SnO, and all three operate at their best at 800 K suggesting high temperature thermoelectric device applications.

Resilience and Renewable Energy Planning in Greenland

DEFF Research Database (Denmark)

Carruth, Susan

2014-01-01

Using a combination of thematic analysis and studio-based planning proposals in West Greenland, this paper proposes that there is more than one interpretation of resilience in renewable energy planning. All energy transitions, from one system to another, are protracted and unpredictable......, and the transition to a renewable energy system is proving no exception. Such a transition is particularly amplified in the context of Greenland – a country undergoing rapid transformation in many fields, including energy. Resilience theory offers an approach for how to plan for this energy transition, but how...... to translate resilience theory into planning practices remains underdeveloped. The paper begins by outlining some of the challenges in planning a transition to renewable energy, and sketching Greenland’s energy landscape. It then discusses the key characteristics of resilience thinking, before proposing...

Renewable energy: An efficient mechanism to improve GDP

International Nuclear Information System (INIS)

Chien Taichen; Hu Jinli

2008-01-01

This article analyzes the effects of renewable energy on GDP for 116 economies in 2003 through Structural Equation Modeling (SEM) approach. In order to decipher the mechanism of how the use of renewables improves macroeconomic efficiency, we decompose GDP by the 'expenditure approach'. Although previous theory predicts positive effects of renewables on capital formation and trade balance, the SEM results show that renewables have a significant positive influence on capital formation only. The result that renewables do not have a significant impact on trade balance implies that renewables do not have an import substitution effect. Thus, we confirm the positive relationship between renewable energy and GDP through the path of increasing capital formation, but not for the path of increasing trade balance

CFD simulation of direct contact condensation with ANSYS CFX using surface renewal theory based heat transfer coefficients

Energy Technology Data Exchange (ETDEWEB)

Wanninger, Andreas; Ceuca, Sabin Cristian; Macian-Juan, Rafael [Technische Univ. Muenchen, Garching (Germany). Dept. of Nuclear Engineering

2013-07-01

Different approaches for the calculation of Direct Contact Condensation (DCC) using Heat Transfer Coefficients (HTC) based on the Surface Renewal Theory (SRT) are tested using the CFD simulation tool ANSYS CFX. The present work constitutes a preliminary study of the flow patterns and conditions observed using different HTC models. A complex 3D flow pattern will be observed in the CFD simulations as well as a strong coupling between the condensation rate and the two-phase flow dynamics. (orig.)

Resilience and Renewable Energy Planning in Greenland

DEFF Research Database (Denmark)

Carruth, Susan

2014-01-01

Using a combination of thematic analysis and studio-based planning proposals in West Greenland, this paper proposes that there is more than one interpretation of resilience in renewable energy planning. All energy transitions, from one system to another, are protracted and unpredictable, and the ......Using a combination of thematic analysis and studio-based planning proposals in West Greenland, this paper proposes that there is more than one interpretation of resilience in renewable energy planning. All energy transitions, from one system to another, are protracted and unpredictable......, and the transition to a renewable energy system is proving no exception. Such a transition is particularly amplified in the context of Greenland – a country undergoing rapid transformation in many fields, including energy. Resilience theory offers an approach for how to plan for this energy transition, but how...... to translate resilience theory into planning practices remains underdeveloped. The paper begins by outlining some of the challenges in planning a transition to renewable energy, and sketching Greenland’s energy landscape. It then discusses the key characteristics of resilience thinking, before proposing...

Tradeoffs for Renewable Energy Projects: Environmental, Planning, and Mission Considerations

Science.gov (United States)

2010-04-01

parabolic trough solar system for heating, cooling and hot water at Fort Huachuca, AZ from October 1979 (est.)  a solar pool heating system at Fort... collectors commercially applied Passive solar energy use Heat, cold, light, ventila- tion Demonstrations and applica- tions Artificial photosynthesis H2...the technologies that convert those energies into more usable forms is that renewable en- ERDC/CERL SR-10-2 36 ergy generally emits fewer compounds

Possible violations of the relativity theory

International Nuclear Information System (INIS)

Tiomno, J.

1985-01-01

A review of previous works of the author and collaborators on possible violations of the Theory of Relativity (SR) is made. It is shown that there is no contradiction of the predictions of the Lorentz Aether Theory, in the form presented in these papers, with existing experiments. Further experiments to detect these violations (or to confirm SR) are indicated. (Author) [pt

Theoretical prediction and experimental confirmation of unusual ternary ordered semiconductor compounds in Sr-Pb-S system.

Science.gov (United States)

Hao, Shiqiang; Zhao, Li-Dong; Chen, Chang-Qiang; Dravid, Vinayak P; Kanatzidis, Mercouri G; Wolverton, Christopher M

2014-01-29

We examine the thermodynamics of phase separation and ordering in the ternary Ca(x)Pb(1-x)S and Sr(x)Pb(1-x)S systems by density-functional theory combined with a cluster expansion and Monte Carlo simulations. Similar to most other ternary III-V or IV-VI semiconductor alloys, we find that bulk phase separation is thermodynamically preferred for PbS-CaS. However, we predict the surprising existence of stable, ordered ternary compounds in the PbS-SrS system. These phases are previously unreported ordered rocksalt-based compounds: SrPb3S4, SrPbS2, and Sr3PbS4. The stability of these predicted ordered phases is confirmed by transmission electron microscopy observations and band gap measurements. We believe this work paves the way for a combined theory-experiment approach to decipher complex phase relations in multicomponent chalcogenide systems.

An ab-initio investigation on SrLa intermetallic compound

Science.gov (United States)

Kumar, S. Ramesh; Jaiganesh, G.; Jayalakshmi, V.

2018-05-01

The electronic, elastic and thermodynamic property of CsCl-type SrLa are investigated through density functional theory. The energy-volume relation for this compound has been obtained. The band structure, density of states and charge density in (110) plane are also examined. The elastic constants (C11, C12 and C44) of SrLa is computed, then, using these elastic constants, the bulk moduli, shear moduli, Young's moduli and Poisson's ratio are also derived. The calculated results showed that CsCl-type SrLa is ductile at ambient conditions. The thermodynamic quantities such as free energy, entropy and heat capacity as a function of temperature are estimated and the results obtained are discussed.

Optimization of 90Sr/89Sr measurements

Directory of Open Access Journals (Sweden)

Legarda F.

2012-04-01

Full Text Available One of the key points in the double measurement method for the measurement of both, 89Sr and 90Sr, by using a proportional counter is the choice of the times at which the measurements should be done. In this paper, the formulae to calculate the 89Sr and 90Sr detection limits in conditions of radioactive equilibrium between 90Y and 90Sr are derived, and an analysis of them as a function of the time between the two measurements is done. The choice for the time of the second measurement is going to depend on the desired quality of the results to be obtained.

Adoption of renewable heating systems: An empirical test of the diffusion of innovation theory

International Nuclear Information System (INIS)

Franceschinis, Cristiano; Thiene, Mara; Scarpa, Riccardo; Rose, John; Moretto, Michele; Cavalli, Raffaele

2017-01-01

The implementation of heating technologies based on renewable resources is an important part of Italy's energy policy. Yet, despite efforts to promote the uptake of such technologies, their diffusion is still limited while heating systems based on fossil fuels are still predominant. Theory suggests that beliefs and attitudes of individual consumers play a crucial role in the diffusion of innovative products. However, empirical studies corroborating such observations are still thin on the ground. We use a Choice Experiment and a Latent Class-Random Parameter model to analyze preferences of households in the Veneto region (North-East Italy) for key features of ambient heating systems. We evaluate the coherence of the underlying preference structure using as criteria psychological constructs from the Theory of Diffusion of Innovation by Rogers. Our results broadly support this theory by providing evidence of segmentation of the population consistent with the individuals' propensity to adopt innovations. We found that preferences for heating systems and respondents' willingness to pay for their key features vary across segments. These results enabled us to generate maps that show how willingness to pay estimates vary across the region and can guide local policy design aimed at stimulating adoption of sustainable solutions. - Highlights: • We relate preferences for wood pellet heating systems to Diffusion of Innovation theory. • We found a segmentation of the population according to individual innovativeness. • Preferences for wood pellet heating systems vary across population segments. • Public intervention seems necessary to foster adoption among late adopters.

Electronic properties and surface reactivity of SrO-terminated SrTiO3 and SrO-terminated iron-doped SrTiO3.

Science.gov (United States)

Staykov, Aleksandar; Tellez, Helena; Druce, John; Wu, Ji; Ishihara, Tatsumi; Kilner, John

2018-01-01

Surface reactivity and near-surface electronic properties of SrO-terminated SrTiO 3 and iron doped SrTiO 3 were studied with first principle methods. We have investigated the density of states (DOS) of bulk SrTiO 3 and compared it to DOS of iron-doped SrTiO 3 with different oxidation states of iron corresponding to varying oxygen vacancy content within the bulk material. The obtained bulk DOS was compared to near-surface DOS, i.e. surface states, for both SrO-terminated surface of SrTiO 3 and iron-doped SrTiO 3 . Electron density plots and electron density distribution through the entire slab models were investigated in order to understand the origin of surface electrons that can participate in oxygen reduction reaction. Furthermore, we have compared oxygen reduction reactions at elevated temperatures for SrO surfaces with and without oxygen vacancies. Our calculations demonstrate that the conduction band, which is formed mainly by the d-states of Ti, and Fe-induced states within the band gap of SrTiO 3 , are accessible only on TiO 2 terminated SrTiO 3 surface while the SrO-terminated surface introduces a tunneling barrier for the electrons populating the conductance band. First principle molecular dynamics demonstrated that at elevated temperatures the surface oxygen vacancies are essential for the oxygen reduction reaction.

Communicating a Renewed Brand Identity

OpenAIRE

Marttila, Oona

2017-01-01

This thesis aims to help the commissioning company in finding a suitable approach to efficiently communicate the renewed brand identity of the company. Theories applied to this research include rebranding, segmentation, as well as theories on customer relationships, service encounters and online marketing. This is complemented by the identification of the company potential through SWOT analysis as well as identifying differentiating factors within the company, in order to gain competitive adv...

An EPR investigation of the dynamic Jahn-Teller effect in SrCl2:y(2 plus) and SrCl2:Sc(2 plus)

Science.gov (United States)

Herrington, J. R.; Estle, T. L.; Boatner, L. A.

1972-01-01

EPR spectra have been observed for SrCl2:Y(2+) and SrCl2:Sc(2+) at liquid helium temperatures. At 1.2 K the spectra were dominated by anisotropic hyperfine patterns whose lineshapes and angular dependences were explained using second order solutions of the effective Hamiltonian for an isolated 2Eg state split by large random internal strains. Pronounced asymmetries in some of the strin produced lineshapes for Srcl2:Sc(2+) are shown to result from second order terms in the solution of the effective Hamiltonian. Coexisting with the anisotropic hyperfine patterns are weak nearly isotropic hyperfine patterns with typical lineshapes. Variations in the apparent intensity of lines in these weak hyperfine patterns as functions of the applied magnetic field direction and temperature imply that these lines result from averaging by vibronic relaxation of a portion of the anisotropic pattern. The effective Hamiltonian parameters for SrCl2:La(2+), SrCl2:y(2+), and SrCl2:SC(2+) are analyzed in terms of crystal field theory modified to include a dynamic Jahn-Teller effect.

Enhanced carrier density in Nb-doped SrTiO3 thermoelectrics

KAUST Repository

Ozdogan, K.

2012-03-08

We study epitaxial SrTiO3 interfaced with Nb-doped SrTi1-x Nb x O3 (x = 0, 0.125, 0.25, 0.375, and 0.5) by full-potential density functional theory. From the electronic band structures obtained by our ab-initio calculations we determine the dependence of the induced metallicity on the Nb concentration. We obtain a monotonous increase of the carrier density with the Nb concentration. The results are confirmed by experiments for SrTi0.88Nb0.12O3 and SrTi0.8Nb0.2O3, demonstrating the predictive power and limitations of our theoretical approach. We also show that the Seebeck coefficient decreases monotonously with increasing temperature.

Enhanced carrier density in Nb-doped SrTiO3 thermoelectrics

KAUST Repository

Ozdogan, K.; Upadhyay Kahaly, M.; Sarath Kumar, S. R.; Alshareef, Husam N.; Schwingenschlö gl, Udo

2012-01-01

We study epitaxial SrTiO3 interfaced with Nb-doped SrTi1-x Nb x O3 (x = 0, 0.125, 0.25, 0.375, and 0.5) by full-potential density functional theory. From the electronic band structures obtained by our ab-initio calculations we determine the dependence of the induced metallicity on the Nb concentration. We obtain a monotonous increase of the carrier density with the Nb concentration. The results are confirmed by experiments for SrTi0.88Nb0.12O3 and SrTi0.8Nb0.2O3, demonstrating the predictive power and limitations of our theoretical approach. We also show that the Seebeck coefficient decreases monotonously with increasing temperature.

Sr_2SmNbO_6 perovskite: Synthesis, characterization and density functional theory calculations

International Nuclear Information System (INIS)

Dutta, Alo; Mukhopadhyay, P.K.; Sinha, T.P.; Shannigrahi, Santiranjan; Himanshu, A.K.; Sen, Pintu; Bandyopadhyay, S.K.

2016-01-01

The density functional theory (DFT) under the generalized gradient approximation (GGA) has been used to investigate the electronic structure of double perovskite oxide Sr_2SmNbO_6 synthesized by the solid-state reaction technique. The Rietveld refinement of the X-ray diffraction pattern of the sample shows the monoclinic P2_1/n phase at room temperature. The X-ray photoemission spectrum (XPS) of the material is collected in the energy window of 0–1200 eV. The chemical shift of the constituent elements calculated from the core level XPS spectra is used to analyze the covalency between the O anion and Sm/Nb cations. The valence band (VB) XPS spectrum is compared with the calculated VB spectrum using partial density of states in a standard way. The Raman spectrum is employed to investigate the phonon modes of the material in the monoclinic phase. Lorentzian lines are used to fit the experimental Raman spectrum, which present 24 phonon modes corresponding to the stretching and banding of NbO_6/SmO_6 octahedra and translational motion of Sr along the Sr−O bond. The discrepancy between the measured and calculated band gap values has been removed by applying modified Becke-Johnson (mBJ) potential in the DFT calculations. The experimental optical band gap obtained from the UV–visible reflectance spectrum is found to be 3.42 eV, which is well matched with the DFT calculated value of 3.2 eV, and suggests the semiconducting nature of the material. The real (ε′) and imaginary (ε″) parts of the optical dielectric constant as a function of energy along the x-, y- and z-polarization directions using mBJ potential are calculated. The collective vibrational modes of the atoms, the Born effective charge of the ions and their effect on the static dielectric constant of the material are studied using DFT. The calculated value of static dielectric constant for SSN is found to be 41.3. - Highlights: • Electronic structure and dynamical properties of Sr_2SmNbO_6 (SSN

A New-Growth Perspective on Non-Renewable Resources

DEFF Research Database (Denmark)

Groth, Christian

This article reviews issues related to the incorporation of non-renewable resources in the theory of economic growth and development. As an offshoot of the new growth theory of the last two decades a series of contributions have studied endogenous technical change in relation to resource scarcity...

Dielectric enhancement of BaTiO3/SrTiO3 superlattices with embedded Ni nanocrystals

International Nuclear Information System (INIS)

Xiong Zhengwei; Sun Weiguo; Wang Xuemin; Jiang Fan; Wu Weidong

2012-01-01

Highlights: ► The BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs were successfully fabricated by L-MBE. ► The influence with the various concentrations of Ni nanocrystals embedded in BaTiO 3 /SrTiO 3 superlattices was also discussed. ► The BaTiO 3 /SrTiO 3 superlattices with lower concentration of embedded Ni NCs had higher permittivity and dielectric loss compared with the pure BaTiO 3 /SrTiO 3 superlattices. ► The dielectric enhancement of BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs was proposed to explained by Drude quasi-free-electron theory. - Abstract: The self-organized Ni nanocrystals (NCs) were embedded in BaTiO 3 /SrTiO 3 superlattices using laser molecular beam epitaxy (L-MBE). The stress of the composite films was increased with the increasing concentration of embedded Ni NCs, as investigation in stress calculation. The influence with the various concentrations of Ni NCs embedded in BaTiO 3 /SrTiO 3 superlattices was also discussed. The internal stress of the films was too strong to epitaxial growth of BaTiO 3 /SrTiO 3 superlattices. Compared with the pure BaTiO 3 /SrTiO 3 superlattices, the BaTiO 3 /SrTiO 3 superlattices with lower concentration of embedded Ni NCs had higher permittivity and dielectric loss. Furthermore, the dielectric enhancement of BaTiO 3 /SrTiO 3 superlattices with embedded Ni NCs was proposed to explained by Drude quasi-free-electron theory.

Growth with Endogenous Capital, Knowledge, and Renewable Resources

OpenAIRE

Wei-Bin Zhang

2017-01-01

This paper proposes a dynamic economic model with endogenous technological change, physical capital and renewable resources. The model is a synthesis of the neoclassical growth theory, Arrow’s learning by doing, and some traditional dynamic models of renewable resources with an alternative approach to household behavior. The model describes a dynamic interdependence between technological change, physical accumulation, resource change, and division of labor under perfect competition. Because o...

Pseudogap and cuprate superconductivity: MaxEnt-μSR studies

International Nuclear Information System (INIS)

Boekema, C.; Schwartz, R.; Love, A.; Browne, M.C.

2013-01-01

Highlights: • A magnetic origin of cuprate superconductivity is plausible. • Cuprate loop currents are observed, close to predictions. • Pseudogap effects are seen above and below T c . -- Abstract: The basic physics of cuprate superconductivity is still much deliberated after 27 years of research. In contrast to phononic or polaronic roots, Varma’s theory promotes a magnetic origin. To probe cuprate magnetism, we examine zero field (ZF) muon-spin-rotation (μSR) data of RBa 2 Cu 3 O 7−δ (RBCO; R = Gd, Eu) especially near T c . Possible weak effects are analyzed using Maximum Entropy (MaxEnt, ME) to transform our μSR time series. Concerning predicted pseudogap loop currents, we have observed μSR signals in zero field for GdBCO above and now also below T c . These are near predicted fields of about 100 Oe. Using MaxEnt, we analyze transverse field (TF) μSR data of optimal doped EuBCO. Our focus is also on a temperature interval above T c to comprehend precursor effects. Our results point toward magnetic roots of cuprate superconductivity

μSR data analysis with XYfit

International Nuclear Information System (INIS)

Tucakov, Ivan; Brewer, Jess H.; Froese, Aaron; Lau, Angus

2006-01-01

The CERN MINUIT library has recently been ported to C++, facilitating the incorporation of that familiar package into a general purpose fitting application called XYfit with a graphical user interface built with Qt3. Custom theory functions can easily be added as 'plugins' to XYfit, which reads in DataTables in XML format generated by the μView spreadsheet utility (which see), thus allowing more flexible fitting of μSR spectra

Strategic Renewal in Regulatory Environments. How inter- and intra-organisational institutional forces influence European incumbent energy firms

International Nuclear Information System (INIS)

Stienstra, M.

2008-01-01

How do incumbent firms strategically renew in regulatory environments? Assuming that regulation can both constrain and enable a firm's strategic renewal opportunities, we investigate how and to what extent incumbent firms undertake exploitative and explorative strategic renewal actions in order to remain competitive. Exploitative strategic renewal involves those actions that strengthen or optimise a firm's current resource deployments, whereas explorative strategic renewal relates to actions that generate new sources of value creation for the firm. Based on old institutional theory, new institutional theory, neo-institutional theory and institutional entrepreneurship literature, a multi-level framework that combines selection and adaptation arguments has been developed and applied to investigate strategic renewal behaviour of a sample of European energy incumbents. At industry level of analysis, results show how inter-organisational institutional forces significantly impact firms' choices of exploitative and explorative strategic renewal actions through regulative, normative and cognitive forces. At organisational unit level of analysis, we find that the extent of intra-organisational regulative forces is positively related to exploitative strategic renewal actions. In addition, entrepreneurial proclivity appears to be a catalyst of both exploitative and explorative strategic renewal actions. Finally, our results provide insights how environmental selection and firm level adaptation are interrelated in the context of regulation. The extent of inter-organisational regulative forces positively moderates the relationship between intra-organisational regulative forces and exploitative strategic renewal actions.

Renewable Resources, Capital Accumulation, and Economic Growth

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2011-01-01

Full Text Available This paper proposes a dynamic economic model with physical capital and renewable resources. Different from most of the neoclassical growth models with renewable resources which are based on microeconomic foundation and neglect physical capital accumulation, this study proposes a growth model with dynamics of renewable resources and physical capital accumulation. The model is a synthesis of the neoclassical growth theory and the traditional dynamic models of renewable resources with an alternative approach to household behavior. The model describes a dynamic interdependence among physical accumulation, resource change, and division of labor under perfect competition. Because of its refined economic structure, our study enables some interactions among economic variables which are not found in the existing literature on economic growth with renewable resources. We simulate the model to demonstrate the existence of equilibrium points and motion of the dynamic system. Our comparative dynamic analysis shows, for instance, that a rise in the propensity to consume the renewable resource increases the interest rate and reduces the national and production sector’s capital stocks, wage rate and level of the consumption good. Moreover, it initially reduces and then increases the capital stocks of the resource sector and the consumption and price of the renewable resource. The stock of the renewable resource is initially increased and then reduced. Finally, labor is redistributed from the production to the resource sector.

Tuning the electronic structure of SrTiO3/SrFeO3−x superlattices via composition and vacancy control

Directory of Open Access Journals (Sweden)

Robert F. Berger

2014-04-01

Full Text Available Using density functional theory-based calculations, we explore the effects of oxygen vacancies and epitaxial layering on the atomic, magnetic, and electronic structure of (SrTiO3n(SrFeO3−x1 superlattices. While structures without oxygen vacancies (x = 0 possess small or non-existent band gaps and ferromagnetic ordering in their iron layers, those with large vacancy concentrations (x = 0.5 have much larger gaps and antiferromagnetic ordering. Though the computed gaps depend numerically on the delicate energetic balance of vacancy ordering and on the value of Hubbard U eff used in the calculations, we demonstrate that changes in layering can tune the band gaps of these superlattices below that of SrTiO3 (3.2 eV by raising their valence band maxima. This suggests the possibility that these superlattices could absorb in the solar spectrum, and could serve as water-splitting photocatalysts.

Workshop on Control Theory Applied to Renewable Resource Management and Ecology

CERN Document Server

Skowronski, Janislaw

1981-01-01

As society becomes stressed by economic and population pressures, in turn, nature's renewable resources become stressed by harvesting pressures. For our own survival and euphoria, it is paramount that such resources remain as their name implies and not be driven to extinction through short term programs of over exploitation. Consideration of the harvesting of renewable resources leads to a simple question that was the theme of the workshop and is the focus of these proceedings: SUPPoRe you are assigned the role of manager for a specific renewable resource eco­ system. How would you decide on harvesting policies so that the system can be exploited economically yet at the same time maintain the integrity of the system? This, of course, is a loaded question. First of all, it is not clear that there is ever anyone single decision maker who is able to set the rules for all of the harvesters in an exploited ecosystem. The political process is complicated and to some extent unpredictable. This aspect of the questio...

Likely market-penetrations of renewable-energy technologies

International Nuclear Information System (INIS)

Probert, S.D.; Mackay, R.M.

1998-01-01

The learning-curve concept is considered to be an important tool for predicting the future costs of renewable-energy technology systems. This paper sets out the underlying rationale for learning-curve theory and the potential for its application to renewable technologies, such as photovoltaic-module and wind-power generator technologies. An indication of the data requirements for carrying out learning-curve projections is given together with an assessment of the requirements necessary for an analysis to be undertaken of the application of learning curves to other renewable-energy technologies. The paper includes a cost comparison and a figure-of-merit criterion applicable to photovoltaic-module and wind-power-turbine technologies. (Copyright (c) 1998 Elsevier Science B.V., Amsterdam. All rights reserved.)

Strategic Renewal in Regulatory Environments. How inter- and intra-organisational institutional forces influence European incumbent energy firms

Energy Technology Data Exchange (ETDEWEB)

Stienstra, M.

2008-11-20

How do incumbent firms strategically renew in regulatory environments? Assuming that regulation can both constrain and enable a firm's strategic renewal opportunities, we investigate how and to what extent incumbent firms undertake exploitative and explorative strategic renewal actions in order to remain competitive. Exploitative strategic renewal involves those actions that strengthen or optimise a firm's current resource deployments, whereas explorative strategic renewal relates to actions that generate new sources of value creation for the firm. Based on old institutional theory, new institutional theory, neo-institutional theory and institutional entrepreneurship literature, a multi-level framework that combines selection and adaptation arguments has been developed and applied to investigate strategic renewal behaviour of a sample of European energy incumbents. At industry level of analysis, results show how inter-organisational institutional forces significantly impact firms' choices of exploitative and explorative strategic renewal actions through regulative, normative and cognitive forces. At organisational unit level of analysis, we find that the extent of intra-organisational regulative forces is positively related to exploitative strategic renewal actions. In addition, entrepreneurial proclivity appears to be a catalyst of both exploitative and explorative strategic renewal actions. Finally, our results provide insights how environmental selection and firm level adaptation are interrelated in the context of regulation. The extent of inter-organisational regulative forces positively moderates the relationship between intra-organisational regulative forces and exploitative strategic renewal actions.

On the “alpha-phase” of Ca{sub 2−x}Sr{sub x}MnO{sub 4} and extending the chemistry of Sr{sub 7−y}Ca{sub y}Mn{sub 4}O{sub 15} to y>1

Energy Technology Data Exchange (ETDEWEB)

Craddock, Sarah; Senn, Mark S.

2017-04-15

There has been renewed interest in the Ruddlesden-Popper phase (n=2) of composition Ca{sub n+1}Mn{sub n}O{sub 3} {sub n+1} in the light of recent research that has highlighted the nature of the improper ferroelectric ground state, which arises due to the couplings between specific combinations of MnO{sub 6} octahedral rotations and tilts. A fruitful route to control these octahedral degrees of freedom, and hence such desired physical properties, is through chemical substitution on the A–site cation i.e. Ca{sub 2−x}Sr{sub x}MnO{sub 4} for n =1, and in light of this, we have reinvestigated the chemistry of this solid solution. Here we focus on a common impurity phase observed during this synthesis which has been termed the “alpha-phase” in the literature. We show that this impurity phase is actually comprised mainly of a structure related to Sr{sub 7}Mn{sub 4}O{sub 15} but is found here with significantly higher Ca substitution than previously believed possible. Sr{sub 7}Mn{sub 4}O{sub 15} is an interesting structural type in its own right, but has been mainly overlooked to date, exhibiting interesting physics related to low dimensional magnetic ordering and dimer interactions, and we show here that the structural type is a likely candidate for exhibiting a multiferroic ground state. The prospect of being able to tune the lattice and the exchange interactions through further chemical substitution is likely to lead to a renewed interest in this material. - Graphical abstract: Extending the chemistry of Sr{sub 7−y}Ca{sub y}Mn{sub 4}O{sub 15} beyond y>1, revealing highly anisotropic cation ordering and tunable magnetic properties. - Highlights: • Chemistry of the unique structural type Sr{sub 7}Mn{sub 4}O{sub 15} is extended to high Ca concentrations. • Cation occupancy model is determined, showing highly anisotropic solubility of Ca on the 7 unique Sr crystallographic sites. • Anomalies in the magnetic susceptibility data are discussed with reference to

Experiences with the determination of Sr-89 and Sr-90 using fast methods; Erfahrungen bei der Bestimmung von {sup 89}Sr und {sup 90}Sr mittels Schnellmethoden

Energy Technology Data Exchange (ETDEWEB)

Kowalik, C.; Fueger, J. [Thueringer Landesanstalt fuer Umwelt und Geologie, Jena (Germany). Landesmessstelle fuer Umweltradioaktivaet

2014-01-20

Quick methods of the measurement of {sup 89}Sr and {sup 90}Sr have a great importance in the supervision of the environmental radioactivity. It is necessary to receive in short time dependable analytical data to be able to carry out suitable assessments or to give recommendations. The aim of the investigations was to be guaranteed the demands for these methods (test preparation, measurement and evaluation). The use of the solid phase extraction by means of commercial Sr Resin trademark columns (4.4' (5')-Di-tert-butylcyclohexanol-18-kronen-6-aether) (Triskem) to the radiochemical separation of the Sr isotopes was suitable. The measurements occurred to the FHT 770 T12 - Multi Low Level Alpha/Beta Sample Counter (Thermo Scientific). The results contain the summary activities of all available Sr isotopes, as for example {sup 89}Sr and {sup 90}Sr. The calculations of the single activities occur about the mathematical algorithm of the linear development on the basis of the works of G. Kanisch. The first results show, this method is suitable for the analysis of {sup 89}Sr and {sup 90}Sr and is used therefore in future in Thuringia.

Electronic structure of (La,Sr)2CuO4 and Ba0.6K0.4BiO3

International Nuclear Information System (INIS)

Howell, R.H.; Sterne, P.A.; Fluss, M.J.; Kaiser, J.H.; Kitazawa, K.; Kojima, H.; Mosley, W.D.; Dykes, J.W.; Shelton, R.N.

1995-01-01

We have measured and calculated the electron-positron momentum distribution of La 2-x Sr x CuO 4 samples for Sr concentrations of 0, 0.1,0.13, and 0.2 and Ba 0.6 K 0.4 BiO 3 . The momentum distribution of all samples contained features derived from the overlap of the positron distribution with the valence electrons. In addition, discontinuities typical of a Fermi surface are seen in the superconducting samples. The form and position of these features are in general agreement with band theory for both La 2-x Sr x CuO 4 and Ba 0.6 K 0.4 BiO 3 . However the evolution of the Fermi surface with doping in La 2-x Sr x CuO 4 differed significantly from expectations based on single electron band theories. (orig.)

A ferroelectric switchable tunnel junction: KNbO{sub 3}/SrTiO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Rahmanizadeh, Kourosh; Bihlmayer, Gustav; Wortmann, Daniel; Bluegel, Stefan [Peter Gruenberg Institut (PGI-1) and Institute for Advanced Simulation (IAS-1), Forschungszentrum Juelich and JARA, 52425 Juelich (Germany)

2012-07-01

The properties of thin oxide films and multilayers are strongly influenced by defects and, therefore, can be controllably tuned by the defect concentration at the interface. For example, due to the charge discontinuity at the SrTiO{sub 3}/KO-KNbO{sub 3}-NbO{sub 2}/SrTiO{sub 3} interface only one direction of polarization in KNbO{sub 3} film is stable. A switchable polarization in KNbO{sub 3} can be realized by creating (oxygen) defects at the interfaces. We carried out density functional theory (DFT) calculations based on the full potential linearized augmented planewave (FLAPW) method as implemented in the FLEUR code for studying the polar interface SrTiO{sub 3}/KNbO{sub 3} and a SrRuO{sub 3}/SrTiO{sub 3}/KNbO{sub 3} tunnel junction. The electronic transport properties of the switchable multiferroic SrRuO{sub 3}/SrTiO{sub 3}/KO-KNbO{sub 3}-NbO{sub 3}/SrTiO{sub 3}/SrRuO{sub 3} heterostructure have been investigated using an embedded Green-function approach. A strong dependence of the (magneto electric) transport properties on the polarization is observed.

Thermoelectric performance enhancement of SrTiO3 by Pr doping

KAUST Repository

Kahaly, M. Upadhyay; Schwingenschlö gl, Udo

2014-01-01

We investigate Pr doping at the Sr site as a possible route to enhance the thermoelectric behavior of SrTiO3-based materials, using first principles calculations in full-potential density functional theory. The effects of the Pr dopant on the local electronic structure and resulting transport properties are compared to common Nb doping. We demonstrate a substantial enhancement of the thermoelectric figure of merit and develop an explanation for the positive effects, which opens new ways for materials optimization by substitutional doping at the perovskite B site. © 2014 the Partner Organisations.

Rapid method for determining Sr-89 and Sr-90 using Cherenkov and proportional counting; Schnellmethode zur Bestimmung von SR-89 und SR-90 durch Cerenkov- und Proportionalzaehlermessungen

Energy Technology Data Exchange (ETDEWEB)

Lange, S.; Wende, C.; Schwokowski, R.; Alisch-Mark, M.; Abraham, A.; Heinrich, T. [Staatliche Betriebsgesellschaft fuer Umwelt und Landwirtschaft, Radebeul (Germany)

2016-07-01

A rapid method for determining Sr-89 and Sr-90 in water, milk and biological samples has been developed and tested. After sample preparation strontium is separated by extraction chromatography using Sr resin. Eluate is divided and transfered to LSC vial and filter paper by SrCO{sub 3} precipitation. A Hidex 300 SL TDCR liquid scintillation counter and Thermo Fisher low level proportional counter have been used. Chemical yield of Sr-85 tracer is determined by Gamma spectroscopy. Uncertainty budget, decision threshold and detection limit are calculated in accordance with GUM and ISO 11929.

Sr{sub 2}SmNbO{sub 6} perovskite: Synthesis, characterization and density functional theory calculations

Energy Technology Data Exchange (ETDEWEB)

Dutta, Alo, E-mail: alo_dutta@yahoo.com [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector III, Salt Lake, Kolkata, 700106 (India); Mukhopadhyay, P.K. [Department of Condensed Matter Physics and Material Sciences, S. N. Bose National Centre for Basic Sciences, Block-JD, Sector III, Salt Lake, Kolkata, 700106 (India); Sinha, T.P. [Department of Physics, Bose Institute, 93/1 Acharya Prafulla Chandra Road, Kolkata, 700 009 (India); Shannigrahi, Santiranjan [Institute of Materials Research and Engineering, Agency for Science Technology and Research, 3 Research Link, Singapore, 117602 (Singapore); Himanshu, A.K.; Sen, Pintu; Bandyopadhyay, S.K. [Variable Energy Cyclotron Centre, 1/AF Bidhannagar, Kolkata, 700064 (India)

2016-08-15

The density functional theory (DFT) under the generalized gradient approximation (GGA) has been used to investigate the electronic structure of double perovskite oxide Sr{sub 2}SmNbO{sub 6} synthesized by the solid-state reaction technique. The Rietveld refinement of the X-ray diffraction pattern of the sample shows the monoclinic P2{sub 1}/n phase at room temperature. The X-ray photoemission spectrum (XPS) of the material is collected in the energy window of 0–1200 eV. The chemical shift of the constituent elements calculated from the core level XPS spectra is used to analyze the covalency between the O anion and Sm/Nb cations. The valence band (VB) XPS spectrum is compared with the calculated VB spectrum using partial density of states in a standard way. The Raman spectrum is employed to investigate the phonon modes of the material in the monoclinic phase. Lorentzian lines are used to fit the experimental Raman spectrum, which present 24 phonon modes corresponding to the stretching and banding of NbO{sub 6}/SmO{sub 6} octahedra and translational motion of Sr along the Sr−O bond. The discrepancy between the measured and calculated band gap values has been removed by applying modified Becke-Johnson (mBJ) potential in the DFT calculations. The experimental optical band gap obtained from the UV–visible reflectance spectrum is found to be 3.42 eV, which is well matched with the DFT calculated value of 3.2 eV, and suggests the semiconducting nature of the material. The real (ε′) and imaginary (ε″) parts of the optical dielectric constant as a function of energy along the x-, y- and z-polarization directions using mBJ potential are calculated. The collective vibrational modes of the atoms, the Born effective charge of the ions and their effect on the static dielectric constant of the material are studied using DFT. The calculated value of static dielectric constant for SSN is found to be 41.3. - Highlights: • Electronic structure and dynamical

Resilience and Renewable Energy Planning in Greenland

DEFF Research Database (Denmark)

Carruth, Susan

2014-01-01

to translate resilience theory into planning practices remains underdeveloped. The paper begins by outlining some of the challenges in planning a transition to renewable energy, and sketching Greenland’s energy landscape. It then discusses the key characteristics of resilience thinking, before proposing...

Environmental 90Sr measurements

Science.gov (United States)

Paul, M.; Berkovits, D.; Cecil, L.D.; Feldstein, H.; Hershkowitz, A.; Kashiv, Y.; Vogt, S.

1997-01-01

90Sr (T1/2 = 28.5 years) is a long-lived radionuclide produced in nuclear fission. Fast radiochemical detection of 90Sr in environmental samples is not feasible using current analytical methods. Accelerator Mass Spectrometry (AMS) measurements of 90Sr were made with the Rehovot 14UD Pelletron accelerator at a terminal voltage of 11 or 12 MV using our standard detection system. Injection of hydride ions (SrH3-) was chosen owing to high beam intensity and low Coulomb explosion effects. 90Sr ions were identified and discriminated from isobaric 90Zr by measuring time of flight, total energy and three independent energy-loss signals in an ionization chamber. A reference sample and a ground-water sample were successfully measured. The detection limit determined for a laboratory blank by the residual counts in the 90Sr region is 90Sr/Sr = 3 ?? 10-13, corresponding in practice to (2-4) ?? 10790Sr atoms or about 0.5-1 pCi/L in environmental water samples.

Maxdose-SR and popdose-SR routine release atmospheric dose models used at SRS

Energy Technology Data Exchange (ETDEWEB)

Jannik, G. T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Trimor, P. P. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-07-28

MAXDOSE-SR and POPDOSE-SR are used to calculate dose to the offsite Reference Person and to the surrounding Savannah River Site (SRS) population respectively following routine releases of atmospheric radioactivity. These models are currently accessed through the Dose Model Version 2014 graphical user interface (GUI). MAXDOSE-SR and POPDOSE-SR are personal computer (PC) versions of MAXIGASP and POPGASP, which both resided on the SRS IBM Mainframe. These two codes follow U.S. Nuclear Regulatory Commission (USNRC) Regulatory Guides 1.109 and 1.111 (1977a, 1977b). The basis for MAXDOSE-SR and POPDOSE-SR are USNRC developed codes XOQDOQ (Sagendorf et. al 1982) and GASPAR (Eckerman et. al 1980). Both of these codes have previously been verified for use at SRS (Simpkins 1999 and 2000). The revisions incorporated into MAXDOSE-SR and POPDOSE-SR Version 2014 (hereafter referred to as MAXDOSE-SR and POPDOSE-SR unless otherwise noted) were made per Computer Program Modification Tracker (CPMT) number Q-CMT-A-00016 (Appendix D). Version 2014 was verified for use at SRS in Dixon (2014).

On experiments to detect possible failures of relativity theory

International Nuclear Information System (INIS)

Rodrigues Junior, W.A.; Tiomno, J.

1985-01-01

Two recently proposed experiments by Kolen and Torr, designed to show failures of Einstein's Special Relativity (SR) are analysed. It is pointed out that these papers contain a number of imprecisions and misconceptions which are cleared out. Also the very spread misconception about anysotropy of propagation of light in vacuum in Lorentz Aether Theory (LAT) is analysed showing that the anysotropy is only a coordinate effect. Comparison of the correct results in LAT theory, leading to violation of SR, with new theoretical and experimental results of Torr et al is made. Some of these new results are shown to be incorrect and/or inconsistent with both SR and LAT. (Author) [pt

Neodymium-doped Sr5(PO4)3F and Sr5(VO4)3F

International Nuclear Information System (INIS)

Corker, D.L.; Nicholls, J.; Loutts, G.B.

1995-01-01

Neodymium-doped Sr 5 (PO 4 ) 3 F [neodymium strontium fluoride phosphate, (Nd,Sr) 5 (PO 4 ) 3 F] and neodymium-doped Sr 5 (VO 4 ) 3 F [neodymium strontium fluoride vanadate, (Nd,Sr) 5 (VO 4 ) 3 F] crystallize in space group P6 3 /m and are isostructural with calcium fluorophosphate, Ca 5 (PO 4 ) 3 F. There are two different Sr sites in Sr 5 (XO 4 ) 3 F, denoted Sr(1) and Sr(2). Using single-crystal X-ray diffraction the two structures were refined to R factors of 2.3 and 2.2%, respectively, showing that Nd is present at both Sr sites in (Sr,Nd) 5 (VO 4 ) 3 F but only at the Sr(2) site in (Sr,Nd) 5 (PO 4 ) 3 F. (orig.)

Is the Modern Marine 87Sr/86Sr Cycle Balanced?

Science.gov (United States)

Peucker-Ehrenbrink, B.

2017-12-01

The marine 87Sr/86Sr record is one of the best-reconstructed isotope records with thousands of high quality measurements spanning the past 800 million years. It records a global signal of tectonic, biotic and climatic processes on Earth. Yet despite decades of research we still do not know whether the current marine Sr budget is in steady state. Studies of the marine 88Sr/86Sr record indicate that sources and sinks do not balance. The magnitude and isotope composition of the terrestrial inputs are being debated, and the magnitude and temporal variability of unradiogenic contributions are not well constrained. Here I provide a revised assessment of all continental sources of Sr to the ocean, including river runoff, submarine groundwater discharge (Beck et al., 2013), dissolution of riverine suspended matter in seawater and dissolution of volcanic ash deposited on the ocean (Jones et al., 2012). I contrast continental sources of Sr with estimates of marine sources of Sr to seawater, specifically high- and low-temperature submarine hydrothermal fluids, as well as diffusive diagenetic fluxes. Best current data imply that unradiogenic submarine hydrothermal inputs to seawater are insufficient to balance the flux of radiogenic continental Sr. The revised assessment of riverine contributions is based on Sr data for almost 230 rivers, an increasing amount of time-series data for such rivers, as well as river discharge and sediment flux data for more than 2000 rivers. Regional sampling biases have been corrected with the aid of digital bedrock maps, specifically along the western margin of North America, East Africa and the large drainage region of Arabia, India and SE Asia. Significant uncertainty in the chemical and isotopic compositions of runoff from Greenland and East Africa remains. The main uncertainty in the budget, however, is related to the possibility that modern rivers do not represent the pre-anthropogenic (natural) state of continental runoff (e.g. Ganges

Experimental autoabsorption curve 90Sr in SrCO3. Efficiency calculation to detection of 90Sr, 90Y and 90Sr + 90Y in a beta gas proportional counter

International Nuclear Information System (INIS)

Gasco, C.; Alvarez, A.

1987-01-01

Strontium-90 has been determined by radiochemical separation techniques in environmental samples. These techniques, of course, cannot separate the two strontium radionuclides from each other of from stable strontium. Consequently the end product of the chemical separation contains all strontium isotopes in SrCO 3 . The beta particules emitted by 90 Sr are absorbed by the SrCO 3 precipitate. This is the main source of error in the activity measurement. It has been prepared sources of 90 Sr in SrCO 3 in order to determinate the counting efficiency and autoabsorption curve. Also detection efficiencies have been calibrated using known activities of 90 Y and equilibrium mixture of 90 Sr+ 90 Y in the same geometry than our samples. The activity of 90 Sr by ingrowth of 90 Y has been calculated by our computer program. (author). 2 figs., 3 refs

Isotope ratio 87Sr/86Sr in limestones from Bambui group, Brazil (MG)

International Nuclear Information System (INIS)

Kawashita, K.; Mizusaki, A.M.P.; Kiang, C.H.

1987-01-01

The Sr composition of ancient seawater can be estimated from the analysis of carbonate rocks and, in some cases, used to estimate the age of the analyzed carbonate. The normalized 87Sr/86Sr ratios in calcium carbonate fractions from 14 core samples in the Bambui Group near Montalvania, MG, were found to range between .7077 and .7280. The higher values are attributable to Sr isotopic exchange between silicate and carbonate phases during diagenesis. The ratio of .7077 obtained in two pure calcium carbonate samples is here suggested as the best aproximation for the 87Sr/86Sr value for the Bambui sea. This ratio is compatible with an age of about 700 Ma., estimated from the published 87Sr/86Sr curve of Veizer and others, an age in accordance with Quadros recent (1987, in preparation) identification of marine acritarchs from the latest Precambrian (Vendian). (author) [pt

Structural and compositional characterization of synthetic (Ca,Sr)-tremolite and (Ca,Sr)-diopside solid solutions

Science.gov (United States)

Gottschalk, M.; Najorka, J.; Andrut, M.

Tremolite (CaxSr1-x)2Mg5[Si8O22/(OH)2] and diopside (CaxSr1-x)Mg[Si2O6] solid solutions have been synthesized hydrothermally in equilibrium with a 1 molar (Ca,Sr)Cl2 aqueous solution at 750°C and 200 MPa. The solid run products have been investigated by optical, electron scanning and high resolution transmission electron microscopy, electron microprobe, X-ray-powder diffraction and Fourier-transform infrared spectroscopy. The synthesized (Ca,Sr)-tremolites are up to 2000 µm long and 30 µm wide, the (Ca,Sr)-diopsides are up to 150 µm long and 20 µm wide. In most runs the tremolites and diopsides are well ordered and chain multiplicity faults are rare. Nearly pure Sr-tremolite (tr0.02Sr-tr0.98) and Sr-diopside (di0.01Sr-di0.99) have been synthesized. A continuous solid solution series, i.e. complete substitution of Sr2+ for Ca2+ on M4-sites exists for (Ca,Sr)-tremolite. Total substitution of Sr2+ for Ca2+ on M2-sites can be assumed for (Ca,Sr)-diopsides. For (Ca,Sr)-tremolites the lattice parameters a, b and β are linear functions of composition and increase with Sr-content whereas c is constant. For the diopside series all 4 lattice parameters are a linear function of composition; a, b, c increase and β decreases with rising Sr-content. The unit cell volume for tremolite increases 3.47% from 906.68 Å3 for tremolite to 938.21 Å3 for Sr-tremolite. For diopside the unit cell volume increases 4.87 % from 439.91 Å3 for diopside to 461.30 Å3 for Sr-diopside. The observed splitting of the OH stretching band in tremolite is caused by different configurations of the next nearest neighbors (multi mode behavior). Resolved single bands can be attributed to the following configurations on the M4-sites: SrSr, SrCa, CaCa and CaMg. The peak positions of these 4 absorption bands are a linear function of composition. They are shifted to lower wavenumbers with increasing Sr-content. No absorption band due to the SrMg configuration on the M4-site is observed. This indicates

Developing and testing a positive theory of instrument choice: Renewable energy policy in the fifty American states

Science.gov (United States)

Ciocirlan, Cristina E.

The environmental economics literature consistently suggests that properly designed and implemented economic incentives are superior to command-and-control regulation in reducing pollution. Economic incentives, such as green taxes, cap-and-trade programs, tax incentives, are able to reduce pollution in a cost-effective manner, provide flexibility to industry and stimulate innovation in cleaner technologies. In the past few decades, both federal and state governments have shown increased use of economic incentives in environmental policy. Some states have embraced them in an active manner, while others have failed to do so. This research uses a three-step analysis. First, it asks why some states employ more economic incentives than others to stimulate consumption of renewable energy by the residential, commercial and industrial sectors. Second, it asks why some states employ stronger incentives than others. And third, it asks why certain states employ certain instruments, such as electricity surcharges, cap-and-trade programs, tax incentives or grants, while others do not. The first two analyses were conducted using factor analysis and multiple regression analysis, while the third analysis employed logistic regression models to analyze the data. Data for all three analyses were obtained from a combination of primary and secondary sources. To address these questions, a theory of instrument choice at the state level, which includes both internal and external determinants of policy-making, was developed and tested. The state level of analysis was chosen. States have proven to be pioneers in designing policies to address greenhouse gases (see, for instance, the recent cap-and-trade legislation passed in California). The theory was operationalized with the help of four models: needs/responsiveness, interest group influence, professionalism/capacity and innovation-and-diffusion. The needs/responsiveness model suggests that states tend to choose more and stronger economic

Robust half-metallicity of hexagonal SrNiO_3

International Nuclear Information System (INIS)

Chen, Gao-Yuan; Ma, Chun-Lan; Chen, Da; Zhu, Yan

2016-01-01

In the rich panorama of the electronic and magnetic properties of 3d transition metal oxides SrMO_3 (M=Ti, V, Cr, Mn, Fe, Co, Ni, Cu), one member (SrNiO_3) is missing. In this paper we use GGA+U method based on density functional theory to examine its properties. It is found that SrNiO_3 is a ferromagnetic half-metal. The charge density map shows a high degree of ionic bonding between Sr and other atoms. Meanwhile, a covalent-bonding Ni–O–Ni–O–Ni chain is observed. The spin density contour of SrNiO_3 further indicates that the magnetic interaction between Ni atoms mediated by O is semicovalent exchange. The density of states are examined to explore the unusual indirect magnetic-exchange mechanism. Corresponding to the total energies results, a robust half-metallic character is observed, suggesting a promising giant magneto-optical Kerr property of the material. The partial density of states are further examined to explore the origin of ferromagnetic half-metallicity. The O atoms are observed to have larger contribution at fermi level than Ni atoms to the spin-polarized states, demonstrating that O atoms play a critical role in ferromagnetic half-metallicity of SrNiO_3. Hydrostatic pressure effect is examined to evaluate how robust the half-metallic ferromagnetism is. - Graphical abstract: (a) The total energy as a function of the lattice constant a for hexagonal SrNiO3 with various magnetic phases. (b) The total electronic density of states for hexagonal SrNiO_3 with FM configuration from GGA+U calculations. (c) Total electron-density distribution in the (110) plane. The colors gradually change from cyan (through pink) to yellow corresponding to charge density value from 0 to 4.0. (d) The magnetization density map in the (110) plane. The colors range from blue (through green) to red corresponding to magnetization density value from −0.15 to 0.45. Black and white contours stand for positive and negative values, respectively. - Highlights: • Hexagonal Sr

Advances in the Surface Renewal Flux Measurement Method

Science.gov (United States)

Shapland, T. M.; McElrone, A.; Paw U, K. T.; Snyder, R. L.

2011-12-01

The measurement of ecosystem-scale energy and mass fluxes between the planetary surface and the atmosphere is crucial for understanding geophysical processes. Surface renewal is a flux measurement technique based on analyzing the turbulent coherent structures that interact with the surface. It is a less expensive technique because it does not require fast-response velocity measurements, but only a fast-response scalar measurement. It is therefore also a useful tool for the study of the global cycling of trace gases. Currently, surface renewal requires calibration against another flux measurement technique, such as eddy covariance, to account for the linear bias of its measurements. We present two advances in the surface renewal theory and methodology that bring the technique closer to becoming a fully independent flux measurement method. The first advance develops the theory of turbulent coherent structure transport associated with the different scales of coherent structures. A novel method was developed for identifying the scalar change rate within structures at different scales. Our results suggest that for canopies less than one meter in height, the second smallest coherent structure scale dominates the energy and mass flux process. Using the method for resolving the scalar exchange rate of the second smallest coherent structure scale, calibration is unnecessary for surface renewal measurements over short canopies. This study forms the foundation for analysis over more complex surfaces. The second advance is a sensor frequency response correction for measuring the sensible heat flux via surface renewal. Inexpensive fine-wire thermocouples are frequently used to record high frequency temperature data in the surface renewal technique. The sensible heat flux is used in conjunction with net radiation and ground heat flux measurements to determine the latent heat flux as the energy balance residual. The robust thermocouples commonly used in field experiments

Neural circuits involved in the renewal of extinguished fear.

Science.gov (United States)

Chen, Weihai; Wang, Yan; Wang, Xiaqing; Li, Hong

2017-07-01

The last 10 years have witnessed a substantial progress in understanding the neural mechanisms for the renewal of the extinguished fear memory. Based on the theory of fear extinction, exposure therapy has been developed as a typical cognitive behavioral therapy for posttraumatic stress disorder. Although the fear memory can be extinguished by repeated presentation of conditioned stimulus without unconditioned stimulus, the fear memory is not erased and tends to relapse outside of extinction context, which is referred to as renewal. Therefore, the renewal is regarded as a great obstruction interfering with the effect of exposure therapy. In recent years, there has been a great deal of studies in understanding the neurobiological underpinnings of fear renewal. These offer a foundation upon which novel therapeutic interventions for the renewal may be built. This review focuses on behavioral, anatomical and electrophysiological studies that interpret roles of the hippocampus, prelimbic cortex and amygdala as well as the connections between them for the renewal of the extinguished fear. Additionally, this review suggests the possible pathways for the renewal: (1) the prelimbic cortex may integrate contextual information from hippocampal inputs and project to the basolateral amygdala to mediate the renewal of extinguished fear memory; the ventral hippocampus may innervate the activities of the basolateral amygdala or the central amygdala directly for the renewal. © 2017 IUBMB Life, 69(7):470-478, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

Ab Initio Description of Disordered Sr1−xKxFe2As2 Using the Coherent Potential Approximation

KAUST Repository

Pulikkotil, J. J.; Schwingenschlö gl, Udo

2010-01-01

The electronic structure of disordered Sr1−xKxFe2As2 is studied by ab initio density functional theory. As no superstructure and/or atomic short range ordering is reported for Sr1−xKxFe2As2, the coherent potential approximation can be used

Influence of doping on the electronic structure of (La, Sr)2CuO4

International Nuclear Information System (INIS)

Howell, R.H.; Fluss, M.J.; Sterne, P.A.; Kaiser, J.H.; Kitazawa, K.; Kojima, H.

1994-01-01

High-statistics (>4 x 10 8 counts), room-temperature measurements of the electron positron momentum density of La 2-x Sr x CuO 4 have been performed for samples with Sr concentrations of x = 0.0, 0.1, 0.13, and 0.2. These spectra have been analyzed in conjunction with theoretical calculations of the electron positron momentum density. The metallic samples show features consistent with the presence of a Fermi surface, but its evolution with increasing Sr concentration does not follow the predictions of band theory. These results may indicate the effects of electron-electron correlation on the electron momentum distribution in the Cu-O plane. 12 refs., 2 figs

Renewable Substitutability Index: Maximizing Renewable Resource Use in Buildings

OpenAIRE

Srinivasan, Ravi; Campbell, Daniel; Wang, Wei

2015-01-01

In order to achieve a material and energy balance in buildings that is sustainable in the long run, there is an urgent need to assess the renewable and non-renewable resources used in the manufacturing process and to progressively replace non-renewable resources with renewables. Such progressive disinvestment in the non-renewable resources that may be substituted with renewable resources is referred to as “Renewable Substitutability” and if implemented, this process will lead to a paradigm sh...

Effect of Wood Aging on Wine Mineral Composition and 87Sr/86Sr Isotopic Ratio.

Science.gov (United States)

Kaya, Ayse D; Bruno de Sousa, Raúl; Curvelo-Garcia, António S; Ricardo-da-Silva, Jorge M; Catarino, Sofia

2017-06-14

The evolution of mineral composition and wine strontium isotopic ratio 87 Sr/ 86 Sr (Sr IR) during wood aging were investigated. A red wine was aged in stainless steel tanks with French oak staves (Quercus sessiliflora Salisb.), with three industrial scale replicates. Sampling was carried out after 30, 60, and 90 days of aging, and the wines were evaluated in terms of general analysis, phenolic composition, total polysaccharides, multielement composition, and Sr IR. Li, Be, Mg, Al, Sc, Ti, V, Mn, Co, Ni, Cu, Zn, Ga, Ge, As, Rb, Sr, Y, Zr, Mo, Sb, Cs, Ba, Pr, Nd, Sm, Eu, Dy, Ho, Er, Yb, Lu, Tl, and Pb elements and 87 Sr/ 86 Sr were determined by quadrupole inductively coupled plasma mass spectrometry (Q-ICP-MS) and Na, K, Ca, and Fe by flame atomic absorption spectrometry (FAAS). Two-way ANOVA was applied to assess wood aging and time effect on Sr IR and mineral composition. Wood aging resulted in significantly higher concentrations of Mg, V, Co, Ni, and Sr. At the end of the aging period, wine exhibited statistically identical Sr IR compared to control. Study suggests that wood aging does not affect 87 Sr/ 86 Sr, not precluding the use of this parameter for wine traceability purposes.

Mid-America Group: A Foundation for Renewal.

Science.gov (United States)

Lorenzo, Albert L.; Blanzy, James J.

Drawing from a review of the literature and on-site observations, this paper sets forth a comprehensive framework for organizational renewal within the community college. Part 1 focuses on the adaptation of organizational life cycle theory to community colleges. Building upon a broadened definition of human development and the related hierarchy of…

The effect of MgO doping on the structure, magnetic and magnetotransport properties of La0.8Sr0.2MnO3 composite

International Nuclear Information System (INIS)

Aezami, A.; Eshraghi, M.; Kameli, P.; Salamati, H.

2007-01-01

Full text: The recent observation of anomalously Colossal Magnetoresistance (CMR) in the La 1-x A x MnO 3 (A = Sr, Ca, Ba or vacancies) system, has spurred renewed interest in studying these doped perovskite manganites. The properties of these materials are explained by double exchange theory of Zener and electron lattice interaction. However, the intrinsic CMR effect in the perovskite manganites is found on a magnetic field scale of several teslas and a narrow temperature range. It was found that, the presence of grain boundaries in polycrystalline samples leads to a large Low Field Magnetoresistance (LFMR) effect over a wide temperature range below the Curie temperature Tc. To achieve LFMR, different properties are considered. One of them is mixing of these CMR materials with secondary insulator phases. In this work, La 0.8 Sr 0.2 MnO 3 (LSMO) was selected as matrix material and MgO as a dopant. The La 0.8 Sr 0.2 MnO 3/x MgO samples with x= 0, 1, 2, 3, 5 and 7.5 Wt.% were prepared by Solid State Reaction method. Studies show that most part of the MgO goes into the perovskite lattice and Mg substituted Mn in LSMO and remainder segregates as a separate phase at the grain boundaries. Results also show that the value of MR decreases for all the doping levels. It seems that, due to the almost same ionic radii of Mg2+ and Mn2+, and at the higher sintering temperature, Mg2+ mostly replaced Mn3+ and weakens double exchange interaction. This speculation has been confirmed by XRD, SEM, susceptibility, resistivity and magnetoresistance analysis and measurements. (authors)

Culture Studies and Self-Actualization Theory.

Science.gov (United States)

Farmer, Rod

1983-01-01

True citizenship education is impossible unless students develop the habit of intelligently evaluating cultures. Abraham Maslow's theory of self-actualization, a theory of innate human needs and of human motivation, is a nonethnocentric tool which can be used by teachers and students to help them understand other cultures. (SR)

Geochronological synthesis of Bahia state and the crustal evolution, based in evolution diagram of Sr and initial rate of Sr87/Sr86

International Nuclear Information System (INIS)

Sato, K.

1986-01-01

The crustal evolution of the ancient terrains of the State of Bahia, Brazil, is attempted with the aid of Sr isotopic results as natural tracers. Some Nd and Pb isotopic data are also available, and support the main conclusions based on Sr evolution diagrams. The analysis of the Sr evolution diagrams shows that the Archean Terrains are mainly formed by accretion from mantle-derived material, but crustal reworking is indicated by the high initial 87 Sr/ 86 Sr value of the Jequie Complex. The Transamazonian mobile belt include both types of materials, but the 87 Sr/ 86 Sr value, generally lower than those of the Jequie Complex, markes improbable a direct derivation. During Middle and Late Proterozoic, the continental crust was already well consolidated, and reworking of crustal material predominated within the Espinhaco and Brasiliano folded systems [pt

Renewable Substitutability Index: Maximizing Renewable Resource Use in Buildings

Directory of Open Access Journals (Sweden)

Ravi S. Srinivasan

2015-05-01

Full Text Available In order to achieve a material and energy balance in buildings that is sustainable in the long run, there is an urgent need to assess the renewable and non-renewable resources used in the manufacturing process and to progressively replace non-renewable resources with renewables. Such progressive disinvestment in the non-renewable resources that may be substituted with renewable resources is referred to as “Renewable Substitutability” and if implemented, this process will lead to a paradigm shift in the way building materials are manufactured. This paper discusses the development of a Renewable Substitutability Index (RSI that is designed to maximize the use of renewable resources in a building and quantifies the substitution process using solar emergy (i.e., the solar equivalent joules required for any item. The RSI of a building or a building component, i.e., floor or wall systems, etc., is the ratio of the renewable resources used during construction, including replacement and maintenance, to the building’s maximum renewable emergy potential. RSI values range between 0 and 1.0. A higher RSI achieves a low-energy building strategy promoting a higher order of sustainability by optimizing the use of renewables over a building’s lifetime from formation-extraction-manufacturing to maintenance, operation, demolition, and recycle.

Likelihood based inference for partially observed renewal processes

NARCIS (Netherlands)

van Lieshout, Maria Nicolette Margaretha

2016-01-01

This paper is concerned with inference for renewal processes on the real line that are observed in a broken interval. For such processes, the classic history-based approach cannot be used. Instead, we adapt tools from sequential spatial point process theory to propose a Monte Carlo maximum

Effects of packaging SrI{sub 2}(Eu) scintillator crystals

Energy Technology Data Exchange (ETDEWEB)

Sturm, Benjamin W., E-mail: sturm1@llnl.gov [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Cherepy, Nerine J.; Drury, Owen B.; Thelin, Peter A.; Fisher, Scott E.; Payne, Stephen A. [Lawrence Livermore National Laboratory, Livermore, CA 94550 (United States); Burger, Arnold [Fisk University, Nashville, TN 37201 (United States); Boatner, Lynn A.; Ramey, Joanne O. [Oak Ridge National Laboratory, Oak Ridge, TN 37830 (United States); Shah, Kanai S.; Hawrami, Rastgo [Radiation Monitoring Devices, Watertown, MA 02472 (United States)

2011-10-01

Recent renewed emphasis placed on gamma-ray detectors for national security purposes has motivated researchers to identify and develop new scintillator materials capable of high energy resolution and growable to large sizes. We have discovered that SrI{sub 2}(Eu) has many desirable properties for gamma-ray detection and spectroscopy, including high light yield of {approx}90,000 photons/MeV and excellent light yield proportionality. We have measured <2.7% FWHM at 662 keV with small detectors (<1 cm{sup 3}) in direct contact with a photomultiplier tube, and {approx}3% resolution at 662 keV is obtained for 1 in.{sup 3} crystals. Due to the hygroscopic nature of SrI{sub 2}(Eu), similar to NaI(Tl), proper packaging is required for field use. This work describes a systematic study performed to determine the key factors in the packaging process to optimize performance. These factors include proper polishing of the surface, the geometry of the crystal, reflector materials and windows. A technique based on use of a collimated {sup 137}Cs source was developed to examine light collection uniformity. Employing this technique, we found that when the crystal is packaged properly, the variation in the pulse height at 662 keV from events near the bottom of the crystal compared to those near the top of the crystal could be reduced to <1%. This paper describes the design and engineering of our detector package in order to improve energy resolution of 1 in.{sup 3}-scale SrI{sub 2}(Eu) crystals.

A potention of renewable energy sources in Slovakia in term of production of electricity

Directory of Open Access Journals (Sweden)

Štefan Kuzevič

2005-11-01

Full Text Available Electro-energetics of Slovak Republic is in this time in state of re-structuralization consequent from responsibilities which SR has with integration to the EU and on the other hand with actual status of production capacities of fossil fuels using in heat power stations and heat stations also the utilization of nuclear energy in nuclear power stations Jaslovské Bohunice and Mochovce. Paradoxically slim representation in production capacities have renewable energy sources, while only one relevant one is utilization of water in small hydro power stations. According to fact, that to the year 2010, the share of renewable sources of energy using in comparing with electric energy has to achieve 21,7% (direction of EU 77/2001. It is necessary to evaluate possibilities of utilization and to specify potential of utilization from technical and economical aspect.

Theory of the orthogonal dimer Heisenberg spin model for SrCu sub 2 (BO sub 3) sub 2

CERN Document Server

Miyahara, S

2003-01-01

The magnetic properties of SrCu sub 2 (BO sub 3) sub 2 are reviewed from a theoretical point of view. SrCu sub 2 (BO sub 3) sub 2 is a new two-dimensional spin gap system and its magnetic properties are well described by a spin-1/2 antiferromagnetic Heisenberg model of the orthogonal dimer lattice. The model has a dimer singlet ground state whose exactness was proven by Shastry and Sutherland for a topologically equivalent model more than 20 years ago. The exactness of the ground state is maintained even if interlayer couplings are introduced for SrCu sub 2 (BO sub 3) sub 2. In the two-dimensional model, quantum phase transitions take place between different ground states for which three phases are expected: a gapped dimer singlet state, a plaquette resonating valence bond state and a gapless magnetic ordered state. Analysis of the experimental data shows that the dimer singlet ground state is realized in SrCu sub 2 (BO sub 3) sub 2. The orthogonality of the dimer bonds, which is the underlying symmetry of th...

Results of field studies on 90SR and stable SR soil-to-plant transfer

International Nuclear Information System (INIS)

Gerzabek, M.H.; Artner, C.; Horak, O.; Mueck, K.

1992-01-01

In 1987 and 1988 at 35 sites plants ready to harvest and the corresponding soils (0 - 20 cm) were collected for 90 Sr and stable strontium analyses. Sample preparation and measurement led to a detection limit of 0.008 Bq 90 Sr kg -1 . The 90 Sr-contamination of Austrian soils ranged from 396 to 1998 Bq m -2 . Known from literature the contribution of the Chernobyl fallout amounted to app. 25 % of the total contamination. Stable strontium contents of the soils were between 6 and 62.5 mg kg -1 . Bariumtriethanolamine extracted 17.7 to 62.3 % of the total stable Sr in soil. 90 Sr-concentrations in cereal grains ranged from 0.03 to 0.67 Bq kg -1 (fresh wight) for maize and barley, respectively. The values for other foodstuff were between 0.15 (white cabbage) and 0.91 Bq kg -1 (spinach). Stable strontium contents were between 0.079 mg kg -1 (maize) and 72.5 mg kg -1 (celery shoot). The following mean 90 Sr soil-to-plant transfer factors for cereal grains were obtained: 0.010 (maize), 0.097 (rye), 0.049 (wheat), 0.095 (barley). Transfer factors for straw were up to 50 times higher (maize). The transfer of 90 Sr into vegetables and potatoes reached the same order of magnitude compared to the cereals. In all cases soil-to-plant transfer of stable Sr was clearly lower up to 60 % of the respective values for 90 Sr. Thus natural stable strontium is less plant available than 90 Sr. The influence of soil parameters on the 90 Sr transfer into plants was examinated by correlation analyses. Increasing exchangeable calcium contents of the soils resulted in a significant reduction of Sr soil-to-barley straw transfer. (authors)

Limits and Prospects of Renewable Energy Sources in Italy

International Nuclear Information System (INIS)

Coiante, D.

2008-01-01

The Italian energy balance for year 2005 is discussed with particular attention on renewable energy production. The potentials of renewable sources are evaluated in terms of energy density that can be obtained from occupied plant area. About 20000 km 2 of sunny barren lands are present in South of Italy, particularly suitable for photovoltaic plants and that corresponds to a potential production of 144 Mtep of primary energy. Therefore, in theory, the photovoltaic energy potential is comparable with energy balance. The grid connection limit due to intermittent power generation of photovoltaic and wind energy systems is considered in relation with the stability of grid power level. Assuming a 25% maximum grid penetration of intermittent power with respect to capacity of active thermoelectric generators, the renewable energy contribution amounts to about 2% of annual energy balance. In front of expectations for a larger contribution, the practical result is the renewable energy production of present systems is marginal, unsuitable for counteracting the global climate crisis. The conclusion is that, for exploiting the large renewable energy potential, is necessary to implement the plants with an energy storage system able to overcome the source intermittency. Without this improvement, the expectations on renewable energy sources could be disappointed. [it

Effect of Sr/Ti Ratio on the Photocatalytic Properties of SrTiO3

International Nuclear Information System (INIS)

Sulaeman, U; Yin, S; Sato, T

2011-01-01

Since strontium titanate is a wide gap semiconductor, it requires UV light to generate the photocatalytic activities. Modification of strontium titanate to show photocatalytic activity under visible light irradiation is the essential work to efficiently utilize the sun light energy for environmental application. It is expected that the synthesis of SrTiO 3 with variation of Sr/Ti atomic ratio could induce the defect crystals having unique photocatalytic properties. The SrTiO 3 with various Sr/Ti atomic ratios were synthesized by microwave-assisted solvothermal reaction of SrCl 2 .6H 2 O and Ti(OC 3 H 7 ) 4 in KOH aqueous solutions with different atomic ratios of Sr/Ti. The products were characterized by TG-DTA, XRD and DRS. The photocatalytic activity was determined by DeNO x ability using LED lamps with the wavelengths of 627 nm (red), 530 nm (green), 445 nm (blue) and 390 nm (UV). The nanoparticles of perovskite type SrTiO 3 with the particle size of 30-40 nm were successfully synthesized. The visible light responsive photocatalytic activity was generated by adding excess amount of Sr. The photocatalytic activity in visible light could be enhanced by an increase in the Sr/Ti atomic ratio up to 1.25, indicating that the visible light responsive photocatalytic activity is due to the generation of new band gap between the conduction band and valence band of SrTiO 3 by the formation of oxygen vacancy.

Business model innovation for sustainable energy: German utilities and renewable energy

International Nuclear Information System (INIS)

Richter, Mario

2013-01-01

The electric power sector stands at the beginning of a fundamental transformation process towards a more sustainable production based on renewable energies. Consequently, electric utilities as incumbent actors face a massive challenge to find new ways of creating, delivering, and capturing value from renewable energy technologies. This study investigates utilities' business models for renewable energies by analyzing two generic business models based on a series of in-depth interviews with German utility managers. It is found that utilities have developed viable business models for large-scale utility-side renewable energy generation. At the same time, utilities lack adequate business models to commercialize small-scale customer-side renewable energy technologies. By combining the business model concept with innovation and organization theory practical recommendations for utility mangers and policy makers are derived. - Highlights: • The energy transition creates a fundamental business model challenge for utilities. • German utilities succeed in large-scale and fail in small-scale renewable generation. • Experiences from other industries are available to inform utility managers. • Business model innovation capabilities will be crucial to master the energy transition

Regional and interspecific variation in Sr, Ca, and Sr/Ca ratios in avian eggshells from the USA.

Science.gov (United States)

Mora, Miguel A; Brattin, Bryan; Baxter, Catherine; Rivers, James W

2011-08-01

To examine regional variation in strontium (Sr), which at high concentrations may reduce eggshell quality, increase egg breakage and reproductive failure, we analyzed Sr, and calcium (Ca) concentrations and Sr/Ca ratios in eggshells from 20 avian species from California, Texas, Idaho, Kansas, and Michigan. In addition, we included data previously reported from Arizona to expand the regional comparisons and to better establish patterns of Sr, and Sr/Ca ratios in bird species across the United States. We found Sr concentrations varied significantly among regions, among species, and among foraging guilds; this variability is strongly influenced by the Sr/Ca ratios in surface water from locations close to the region where the eggshells were collected. Sr concentrations and Sr/Ca ratios were significantly higher in bird eggshells from the Volta wildlife region in the San Joaquin Valley, California and in various locales from Arizona. Sr concentrations and Sr/Ca ratios in bird eggshells from other locations in the USA were lower than those detected in these two regions. Among foraging guilds, invertivores had the highest Sr concentrations and Sr/Ca ratios and carnivores had the lowest. In general, the Sr/Ca ratio increased strongly with increasing Sr concentrations (R(2) = 0.99, P eggshells suggesting that these values could be determined from Sr/Ca ratios in water. Eggshell thickness was poorly correlated with Sr (R(2) = 0.03) but had a significant and positive correlation with Ca and was more properly correlated by a quadratic equation (R(2) = 0.50, Thickness = 2.13 - 0.02Ca - 3.07 * 10(-5)Ca(2)). Our study provides further evidence that Sr accumulates significantly in the avian eggshell, in some regions at concentrations which could be of concern for potential negative effects on reproduction. We suggest that when assessing the effects of metals on avian reproduction in regions with high Sr deposits in rock and soil, Sr concentrations in the eggshell also should be

Localized-itinerant dichotomy and unconventional magnetism in SrRu2O6

Energy Technology Data Exchange (ETDEWEB)

Okamoto, Satoshi; Ochi, Masayuki; Arita, Ryotaro; Yan, Jiaqiang; Trivedi, Nandini

2017-09-13

Electron correlations tend to generate local magnetic moments that usually order if the lattices are not too frustrated. The hexagonal compound SrRu$_2$O$_6$ has a relatively high N{\\'e}el temperature but small local moments, which seem to be at odds with the nominal valence of Ru$^{5+}$ in the $t_{2g}^3$ configuration. Here, we investigate the electronic and magnetic properties of SrRu$_2$O$_6$ using density functional theory (DFT) combined with dynamical mean field theory (DMFT). We find that the strong hybridization between Ru $d$ and O $p$ states results in a Ru valence that is closer to $+4$, leading to the small ordered moment, consistent with a DFT prediction. While the agreement with DFT might indicate that SrRu$_2$O$_6$ is in the weak coupling regime, our DMFT studies provide evidence from the mass enhancement and local moment formation that indicate correlation effects play a significant role. The local moment per Ru site is about a factor 2 larger than the ordered moment at low temperatures and remains finite in the whole temperature range investigated. Our theoretical N{\\'e}el temperature $\\sim 700$~K is in reasonable agreement with experimental observations. Due to a small lattice distortion, the degenerate $t_{2g}$ manifold is split and the quasiparticle weight is renormalized significantly in the $a_{1g}$ state, while correlation effects in $e_g'$ states are about a factor of 2--3 weaker. SrRu$_2$O$_6$ is a unique system in which localized and itinerant electrons coexist with the proximity to an orbitally-selective Mott transition within the $t_{2g}$ sector.

How Correlated is the FeSe /SrTiO3 System?

Science.gov (United States)

Mandal, Subhasish; Zhang, Peng; Ismail-Beigi, Sohrab; Haule, K.

2017-08-01

Recent observation of ˜10 times higher critical temperature in a FeSe monolayer compared with its bulk phase has drawn a great deal of attention because the electronic structure in the monolayer phase appears to be different than bulk FeSe. Using a combination of density functional theory and dynamical mean field theory, we find electronic correlations have important effects on the predicted atomic-scale geometry and the electronic structure of the monolayer FeSe on SrTiO3 . The electronic correlations are dominantly controlled by the Se-Fe-Se angle either in the bulk phase or the monolayer phase. But the angle sensitivity increases and the orbital differentiation decreases in the monolayer phase compared to the bulk phase. The correlations are more dependent on Hund's J than Hubbard U . The observed orbital selective incoherence to coherence crossover with temperature confirms the Hund's metallic nature of the monolayer FeSe. We also find electron doping by oxygen vacancies in SrTiO3 increases the correlation strength, especially in the dx y orbital by reducing the Se-Fe-Se angle.

Facile Synthesis of SrCO3-Sr(OH2/PPy Nanocomposite with Enhanced Photocatalytic Activity under Visible Light

Directory of Open Access Journals (Sweden)

Alfredo Márquez-Herrera

2016-01-01

Full Text Available Pyrrole monomer was chemically polymerized onto SrCO3-Sr(OH2 powders to obtain SrCO3-Sr(OH2/polypyrrole nanocomposite to be used as a candidate for photocatalytic degradation of methylene blue dye (MB. The material was characterized by Fourier transform infrared (FTIR spectroscopy, UV/Vis spectroscopy, and X-ray diffraction (XRD. It was observed from transmission electronic microscopy (TEM analysis that the reported synthesis route allows the production of SrCO3-Sr(OH2 nanoparticles with particle size below 100 nm which were embedded within a semiconducting polypyrrole matrix (PPy. The SrCO3-Sr(OH2 and SrCO3-Sr(OH2/PPy nanocomposites were tested in the photodegradation of MB dye under visible light irradiation. Also, the effects of MB dye initial concentration and the catalyst load on photodegradation efficiency were studied and discussed. Under the same conditions, the efficiency of photodegradation of MB employing the SrCO3-Sr(OH2/PPy nanocomposite increases as compared with that obtained employing the SrCO3-Sr(OH2 nanocomposite.

First-Principle Predictions of Electronic Properties and Half-Metallic Ferromagnetism in Vanadium-Doped Rock-Salt SrO

Science.gov (United States)

Berber, Mohamed; Doumi, Bendouma; Mokaddem, Allel; Mogulkoc, Yesim; Sayede, Adlane; Tadjer, Abdelkader

2018-01-01

We have used first-principle methods of density functional theory within the full potential linearized augmented plane wave scheme to investigate the electronic and magnetic properties of cubic rock-salt, SrO, doped with vanadium (V) impurity as Sr1- x V x O at various concentrations, x = 0.25, 0.5, and 0.75. We have found that the ferromagnetic state arrangement of Sr1- x V x O is more stable compared to the anti-ferromagnetic state configuration. The electronic structures have a half-metallic (HM) ferromagnetic (F) behavior for Sr0.75V0.25O and Sr0.5V0.5O. This feature results from the metallic and semiconducting natures of majority-spin and minority-spin bands, respectively. The HMF gap decreases with the increasing concentration of vanadium atoms due to the broadening of 3 d (V) levels in the gap, and hence the Sr0.25V0.75O becomes metallic ferromagnetic. The Sr0.75V0.25O revealed a large HM gap with spin polarization of 100%. The Sr1- x V x O compound at low concentrations seems a better candidate to explore the half-metallicity for practical spintronics applications.

Renewable Substitutability Index: Maximizing Renewable Resource Use in Buildings

Science.gov (United States)

In order to achieve a material and energy balance in buildings that is sustainable in the long run, there is an urgent need to assess the renewable and non-renewable resources used in the manufacturing process and to progressively replace non-renewable resources with renewables. ...

Coral Sr-U Thermometry

Science.gov (United States)

DeCarlo, T. M.; Gaetani, G. A.; Cohen, A. L.; Foster, G. L.; Alpert, A.; Stewart, J.

2016-12-01

Coral skeletons archive the past two millennia of climate variability in the oceans with unrivaled temporal resolution. However, extracting accurate temperature information from coral skeletons is confounded by "vital effects", which often override the temperature dependence of geochemical proxies. Here, we present a new approach to coral paleothermometry based on results of abiogenic precipitation experiments interpreted within a framework provided by a quantitative model of the coral biomineralization process. We conducted laboratory experiments to test the temperature and carbonate chemistry controls on abiogenic partitioning of Sr/Ca and U/Ca between aragonite and seawater, and we modeled the sensitivity of skeletal composition to processes occurring at the site of calcification. The model predicts that temperature can be accurately reconstructed from coral skeleton by combining Sr/Ca and U/Ca ratios into a new proxy, Sr-U. We tested the model predictions with measured Sr/Ca and U/Ca ratios of fourteen Porites sp. corals collected from the tropical Pacific Ocean and the Red Sea, with a subset also analyzed using the boron isotope (δ11B) pH proxy. Observed relationships among Sr/Ca, U/Ca, and δ11B agree with model predictions, indicating that the model accounts for the key features of the coral biomineralization process. We calibrated Sr-U to instrumental temperature records and found that it captures 93% of mean annual variability (26-30 °C) and predicts temperature within 0.5 °C (1 σ). Conversely, Sr/Ca alone has an error of prediction of 1 °C and often diverges from observed temperature by 3 °C or more. Many of the problems afflicting Sr/Ca - including offsets among neighboring corals and decouplings from temperature during coral stress events - are reconciled by Sr-U. By accounting for the influence of the coral biomineralization process, the Sr-U thermometer may offer significantly improved reliability for reconstructing ocean temperatures from coral

Solar Thermochemical Energy Storage Through Carbonation Cycles of SrCO3/SrO Supported on SrZrO3.

Science.gov (United States)

Rhodes, Nathan R; Barde, Amey; Randhir, Kelvin; Li, Like; Hahn, David W; Mei, Renwei; Klausner, James F; AuYeung, Nick

2015-11-01

Solar thermochemical energy storage has enormous potential for enabling cost-effective concentrated solar power (CSP). A thermochemical storage system based on a SrO/SrCO3 carbonation cycle offers the ability to store and release high temperature (≈1200 °C) heat. The energy density of SrCO3/SrO systems supported by zirconia-based sintering inhibitors was investigated for 15 cycles of exothermic carbonation at 1150 °C followed by decomposition at 1235 °C. A sample with 40 wt % of SrO supported by yttria-stabilized zirconia (YSZ) shows good energy storage stability at 1450 MJ m(-3) over fifteen cycles at the same cycling temperatures. After further testing over 45 cycles, a decrease in energy storage capacity to 1260 MJ m(-3) is observed during the final cycle. The decrease is due to slowing carbonation kinetics, and the original value of energy density may be obtained by lengthening the carbonation steps. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electronic structure and visible light photocatalysis water splitting property of chromium-doped SrTiO3

International Nuclear Information System (INIS)

Liu, J.W.; Chen, G.; Li, Z.H.; Zhang, Z.G.

2006-01-01

Cr-doped SrTi 1- x Cr x O 3 (x=0.00, 0.02, 0.05, 0.10) powders, prepared by solvothermal method, were further characterized by ultraviolet-visible (UV-vis) absorption spectroscopy. The UV-vis spectra indicate that the SrTi 1- x Cr x O 3 powders can absorb not only UV light like pure SrTiO 3 powder but also the visible-light spectrum (λ>420 nm). The results of density functional theory (DFT) calculation illuminate that the visible-light absorption bands in the SrTi 1- x Cr x O 3 catalyst are attributed to the band transition from the Cr 3d to the Cr 3d+Ti 3d hybrid orbital. The photocatalytic activities of chromium-doped SrTiO 3 both under UV and visible light are increased with the increase in the amounts of chromium. -- Graphical abstract: SrTi 1- x Cr x O 3 powders, prepared by solvothermal method, can absorb not only UV light like pure SrTiO 3 powder but also the visible-light spectrum (λ>420 nm). The results of DFT calculation illuminate that the visible-light absorption bands in the SrTi 1- x Cr x O 3 catalyst are attributed to the band transition from the Cr 3d to the Cr 3d+Ti 3d hybrid orbital

Windfall profit in portfolio diversification? An empirical analysis of the potential benefits of renewable energy investments

Energy Technology Data Exchange (ETDEWEB)

Bruns, Frederik

2013-05-01

Modern Portfolio Theory is a theory which was introduced by Markowitz, and which suggests the building of a portfolio with assets that have low or, in the best case, negative correlation. In times of financial crises, however, the positive diversification effect of a portfolio can fail when Traditional Assets are highly correlated. Therefore, many investors search for Alternative Asset classes, such as Renewable Energies, that tend to perform independently from capital market performance. 'Windfall Profit in Portfolio Diversification?' discusses the potential role of Renewable Energy investments in an institutional investor's portfolio by applying the main concepts from Modern Portfolio Theory. Thereby, the empirical analysis uses a unique data set from one of the largest institutional investors in the field of Renewable Energies, including several wind and solar parks. The study received the Science Award 2012 of the German Alternative Investments Association ('Bundesverband Alternative Investments e.V.').

Polarizable embedding with a multiconfiguration short-range density functional theory linear response method

DEFF Research Database (Denmark)

Hedegård, Erik D.; Olsen, Jógvan Magnus Haugaard; Knecht, Stefan

2015-01-01

. To demonstrate the capabilities of PE-MC-srDFT, we also investigated the retinylidene Schiff base chromophore embedded in the channelrhodopsin protein. While using a much more compact reference wave function in terms of active space, our PE-MC-srDFT approach yields excitation energies comparable in quality......We present here the coupling of a polarizable embedding (PE) model to the recently developed multiconfiguration short-range density functional theory method (MC-srDFT), which can treat multiconfigurational systems with a simultaneous account for dynamical and static correlation effects. PE......-MC-srDFT is designed to combine efficient treatment of complicated electronic structures with inclusion of effects from the surrounding environment. The environmental effects encompass classical electrostatic interactions as well as polarization of both the quantum region and the environment. Using response theory...

CHARACTERIZATION OF THE PARTIALLY PURIFIED PLANTARCIN SR18 PRODUCED BY LACTOBACILLUS PLANTARUM SR18

Directory of Open Access Journals (Sweden)

Wagih El-Shouny

2013-04-01

Full Text Available The bacteriocin bound to the cells and that secreted into the culture filtrate of Lactobacillus plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. Bacteriocins were purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and culture filtrate proteins (plantarcin SR18 b, respectively. The SDS-PAGE of partially purified Plantarcin SR18a showed a molecular weight of 3.5 KDa. While, plantarcin SR18 b had a molecular weight of 10.3 KDa. The antibacterial activity of the tested plantarcin SR18 preparations suffered no measurable loss after 45 min at 80ºC. Whereas, At 100ºC, significant decrease in the activity of bacteriocin preparations (60- 80 % took place by the end of 45 min. At pH ranged from 5-8, the activity of the plantarcin SR18 preparations suffered no measurable loss. Dissociating agents significantly affected the bacteriocin activity. Thus, tween 80 and mercaptoethanol increased the activity of bacteriocin preparations to 1.2-1.4 fold. Sodium dodecyl sulphate (SDS increased the activity of the tested bacteriocin preparations by about 20%.The lowest residual activity (60% was recorded after treatment with Triton X100 for 45 min. Protease completely inhibited the activities of all forms of plantarcin SR18 after 45 min at 37ºC.

Prominent soft x-ray lines of Sr-like Au41+ in low-energy EBIT spectrum

International Nuclear Information System (INIS)

Vilkas, Marius Jonas; Ishikawa, Yasuyuki; Traebert, Elmar

2007-01-01

Relativistic multireference Moeller-Plesset perturbation theory has been employed to calculate with high accuracy the energy levels and transition probabilities of Cu- to Sr-like gold ions. The many-body calculations were carried out to identify the unassigned blended lines in the 35-40 A region of the low-energy EBIT spectrum of the gold ions [Traebert et al 2001 Can. J. Phys.79153]. Most of the prominent lines in the 35-40 A region were identified as the emission lines in Sr-like gold

Electronic parameters of Sr2M2O7 (M = V, Nb, Ta) and Sr-O chemical bonding

DEFF Research Database (Denmark)

Atuchin, Victor V.; Grivel, Jean-Claude; Zhang, Zhaoming

2010-01-01

XPS measurements were carried out on Sr2Nb2O7 and Sr2Ta2O7 powder samples, which were synthesized using standard solid state method. The binding energy differences between the O 1s and cation core level, Δ(O-Sr) = BE(O 1s) - BE(Sr 3d5/2), was used to characterize the valence electron transfer...... on the formation of the Sr-O bonds. The chemical bonding effects were considered on the basis of our XPS results for Sr2Nb2O7 and Sr2Ta2O7 and the previously published structural and XPS data for other Sr-oxide compounds. A new empirical relationship between Δ(O-Sr) and L(Sr-O) was obtained. Possible applications...

Bi-Sr-Ca-Cu-O superconducting thin films: theory and experiment

Energy Technology Data Exchange (ETDEWEB)

Yavuz, M [Department of Mechanical Engineering and Mechatronics Engineering Program, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Boybay, M S [Department of Mechanical Engineering and Mechatronics Engineering Program, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Elbuken, C [Department of Mechanical Engineering and Mechatronics Engineering Program, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada); Andrews, M J [Los Alamos National Lab, PO Box 1663, Mail Stop B 296, Los Alamos, NM 87545 (United States); Hu, C R [Department of Physics, Texas A and M University, College Station, Texas 77843 (United States); Ross, J H [Department of Physics, Texas A and M University, College Station, Texas 77843 (United States)

2006-06-01

The interest of this paper centers on fabrication and characterization and modeling of vortices in high temperature superconducting thin films. As a first step, the magnetic vertices of the superconducting matrix were modeled. As a second, Bi-Sr-Ca-Cu-O thin films were grown using Pulsed Laser Ablation (PLD) on single crystal MgO substrates as magnetic templates for the potential use for Nano and Microelectronic circuits, and were characterized by x-ray diffraction, electron, and atomic force microscopy. The third step (future work) will be observation and pinning of these vortices using Bitter decoration.

Systematic variations of 87Sr/56Sr ratios, Sr compositions, selected major-oxide concentrations, and mineral abundances in piston cores from the Red Sea

International Nuclear Information System (INIS)

Boger, P.D.; Boger, J.L.; Faure, G.

1980-01-01

A mixing model is presented which relates the concentrations of Sr to the 87 Sr/ 86 Sr ratios and concentrations of other elements contained in a mixture of two components. The model is applied to the measured 87 Sr/ 86 Sr ratios, Sr, CaO, Fe 2 O 3 and SiO 2 concentrations of the detrital fractions of sediment from three piston cores representing different depositional environments in the Red Sea. The sediment is shown to be a mixture of two components derived from old sialic rocks and young volcanic rocks of the surrounding land masses. One of the cores contained a third component which is identified as authigenic Fe 2 O 3 . Removal of this contaminant is shown to return the system to its original detrital constituents. (Auth.)

Addition to the analysis of the Sr VI and Sr VII spectra

International Nuclear Information System (INIS)

Wyart, J.F.

1989-01-01

Fifty-six lines of multicharged strontium are measured with an improved wavelength accuracy, or interpreted for the first time. They are 4p-4s, 4p-5s and 4p-4d transitions in Sr VII and 4p-5s transitions in Sr VI. The revision of the singlet-triplet connection in Sr VII is supported by theoretical survey of the ground configuration in Ge-like ions. (orig.)

The renewable alternative

International Nuclear Information System (INIS)

Anon.

1992-01-01

This chapter discusses renewable energy sources as an alternative to a fossil fuel based economy. The topics discussed in the chapter include the historic aspects and current status of use of renewable energy, status of the renewable energy industry, market barriers to renewable energy, research and development and commercialization of renewable energy, the environmental and social costs associated with renewable energy, valuing future costs and benefits of energy use, and the potential market of renewable energy

Interactions between renewable energy policy and renewable energy industrial policy: A critical analysis of China's policy approach to renewable energies

International Nuclear Information System (INIS)

Zhang, Sufang; Andrews-Speed, Philip; Zhao, Xiaoli; He, Yongxiu

2013-01-01

This paper analyzes China's policy approach to renewable energies and assesses how effectively China has met the ideal of appropriate interactions between renewable energy policy and renewable energy industrial policy. First we briefly discuss the interactions between these two policies. Then we outline China's key renewable energy and renewable industrial policies and find that China's government has well recognized the need for this policy interaction. After that, we study the achievements and problems in China's wind and solar PV sector during 2005–2012 and argue that China's policy approach to renewable energies has placed priority first on developing a renewable energy manufacturing industry and only second on renewable energy itself, and it has not effectively met the ideal of appropriate interactions between renewable energy policy and renewable energy industrial policy. Lastly, we make an in-depth analysis of the three ideas underlying this policy approach, that is, the green development idea, the low-carbon leadership idea and indigenous innovation idea. We conclude that Chinas' policy approach to renewable energies needs to enhance the interactions between renewable energy policy and renewable energy industrial policy. The paper contributes to a deeper understanding of China's policy strategy toward renewable energies. -- Highlights: •Interactions between renewable energy policy and renewable energy industrial policy are discussed. •China's key renewable energy and renewable energy industrial policies are outlined. •Two empirical cases illustrate China's policy approach to renewable energies. •We argue that China needs to enhance the interactions between the two policies. •Three ideas underlie China's policy approach to renewable energies

Accessible switching of electronic defect type in SrTi O3 via biaxial strain

Science.gov (United States)

Chi, Yen-Ting; Youssef, Mostafa; Sun, Lixin; Van Vliet, Krystyn J.; Yildiz, Bilge

2018-05-01

Elastic strain is used widely to alter the mobility of free electronic carriers in semiconductors, but a predictive relationship between elastic lattice strain and the extent of charge localization of electronic defects is still underdeveloped. Here we considered SrTi O3 , a prototypical perovskite as a model functional oxide for thin film electronic devices and nonvolatile memories. We assessed the effects of biaxial strain on the stability of electronic defects at finite temperature by combining density functional theory (DFT) and quasiharmonic approximation (QHA) calculations. We constructed a predominance diagram for free electrons and small electron polarons in this material, as a function of biaxial strain and temperature. We found that biaxial tensile strain in SrTi O3 can stabilize the small polaron, leading to a thermally activated and slower electronic transport, consistent with prior experimental observations on SrTi O3 and distinct from our prior theoretical assessment of the response of SrTi O3 to hydrostatic stress. These findings also resolved apparent conflicts between prior atomistic simulations and conductivity experiments for biaxially strained SrTi O3 thin films. Our computational approach can be extended to other functional oxides, and for the case of SrTi O3 our findings provide concrete guidance for conditions under which strain engineering can shift the electronic defect type and concentration to modulate electronic transport in thin films.

Ground-state properties of exotic nuclei near Z=40 in the relativistic mean-field theory

International Nuclear Information System (INIS)

Lalazissis, G.A.

1995-01-01

Study of the ground-state properties of Kr, Sr and Zr isotopes has been performed in the framework of the relativistic mean-field (RMF) theory using the recently proposed relativistic parameter set NL-SH. It is shown that the RMF theory provides an unified and excellent description of the binding energies, isotope shifts and deformation properties of nuclei over a large range of isospin in the Z=40 region. It is observed that the RMF theory with the force NL-SH is able to describe the anomalous kinks in isotope shifts in Kr and Sr nuclei, the problem which has hitherto remained unresolved. This is in contrast with the density-dependent Skyrme-Hartree-Fock approach which does not reproduce the behaviour of the isotope shifts about shell closure. On the Zr chain we predict that the isotope shifts exhibit a trend similar to that of the Kr and Sr nuclei. The RMF theory also predicts shape coexistence in heavy Sr isotopes. Several dramatic shape transitions in the isotopic chains are shown to be a general feature of nuclei in this region. A comparison of the properties with the available mass models shows that the results of the RMF theory are generally in accord with the predictions of the finite-range droplet model. ((orig.))

Some advance on the comprehension of SR analysis for estimating the flux of a scalar

Science.gov (United States)

Castellví, Dr

2009-04-01

In agronomy, the eddy covariance, EC, method likely is the preferred for measuring surface scalar fluxes. For latent heat flux, however, weighing lysimeters maybe preferred in agriculture, but they are rarely affordable and not portable. The dissipation method, DM, is considered the most reliable technique for measuring scalar fluxes over open water because instrument motion contaminates the EC measurements. The main advantage of DM over EC is that it is less sensitive to low frequency instrument platform motions (such as ship and buoys), sensor alignment, precise orientation and stringent steadiness in the mean meteorological conditions (Fairall and Larsen, 1986; Kader, 1992; Edson and Fairall, 1998). Over land, keeping in mind that the EC and DM methods require the same measurements for scalar flux measurement, the DM has several disadvantages versus the EC. Direct measurement of the scalar variance dissipation rate, VDR, requires to capture eddies in the Kolmogorov's microscale (thus scalar time series measured at frequencies in the order of kHz are needed). Therefore, it is not practical. Indirect methods to estimate VDR (such as spectral analysis and second or third order structure functions) requires implementing iterative methods involving similarity relationships that are not well established (Hsieh and Katul, 1997; Castellvi and Snyder, 2008). Currently, there is ample evidence that the DM as explained in traditional micrometeorological books (such as, Panofsky and Dutton, 1984; Brutsaert, 1988; Kaimal and Finnigan; 1994) is, in general, not correct. Accordingly, it likely explains why DM is typically omitted in revisits of micrometeorological methods for estimating scalar fluxes in agronomy. Within the last decade, over some agricultural surfaces, evidence has been shown on the advantages over other micrometeorological methods and the reliability (i.e., close performance to the EC method) of Surface Renewal, SR, theory in conjunction with the Analysis of

Strontium (Sr) separation from seawater using titanate adsorbents: Effects of seawater matrix ions on Sr sorption behavior

Science.gov (United States)

Ryu, Jungho; Hong, Hye-jin; Ryu, Taegong; Park, In-Su

2017-04-01

Strontium (Sr) which has many industrial applications such as ferrite magnet, ceramic, and fire works exists in seawater with the concentration of approximately 7 mg/L. In previous report estimating economic potential on recovery of various elements from seawater in terms of their commercial values and concentrations in seawater, Sr locates upper than approximate break-even line, which implies Sr recovery from seawater can be potentially profitable. Recently, Sr separation from seawater has received great attention in the environmental aspect after Fukushima Nuclear Power Plant (NPP) accident which released much amount of radioactive Sr and Cs. Accordingly, the efficient separation of radioactive elements released to seawater has become critical as an important technological need as well as their removal from radioactive wastes. So far, it has been introduced to separate Sr from aqueous media by various methods including solvent extraction, adsorption by solid materials, and ion exchange. Among them, the adsorption technique using solid adsorbents is of great interest for selectively separating Sr from seawater with respect to low concentration level of Sr. In this study, we synthesized titanate nanotube (TiNT) by simple hydrothermal reaction, characterized its physicochemical properties, and systematically evaluated Sr sorption behavior under various reaction conditions corresponding to seawater environment. The synthesized TiNT exhibited the fibril-type nanotube structure with high specific surface area of 260 m2/g. The adsorption of Sr on TiNT rapidly occurred following pseudo-second-order kinetic model, and was in good agreement with Langmuir isotherm model, indicating maximum adsorption capacity of 97 mg/g. Based on Sr uptake and Na release with stoichiometric balance, sorption mechanism of Sr on TiNT was found to be ion-exchange between Na in TiNT lattice and Sr in solution phase, which was also confirmed by XRD and Raman analysis. Among competitive ions, Ca

Input of 87Sr/86Sr ratios and Sr geochemical signatures to update knowledge on thermal and mineral waters flow paths in fractured rocks (N-Portugal)

International Nuclear Information System (INIS)

Marques, J.M.; Carreira, P.M.; Goff, F.; Eggenkamp, H.G.M.; Antunes da Silva, M.

2012-01-01

Strontium isotopes and other geochemical signatures are used to determine the relationships between CO 2 -rich thermal (Chaves: 76 °C) and mineral (Vilarelho da Raia, Vidago and Pedras Salgadas: 17 °C) waters discharging along one of the major NNE–SSW trending faults in the northern part of mainland Portugal. The regional geology consists of Hercynian granites (syn-tectonic-310 Ma and post-tectonic-290 Ma) intruding Silurian metasediments (quartzites, phyllites and carbonaceous slates). Thermal and mineral waters have 87 Sr/ 86 Sr isotopic ratios between 0.716713 and 0.728035. 87 Sr/ 86 Sr vs. 1/Sr define three end-members (Vilarelho da Raia/Chaves, Vidago and Pedras Salgadas thermal and mineral waters) trending from rainfall composition towards that of the CO 2 -rich thermal and mineral waters, indicating different underground flow paths. Local granitic rocks have 87 Sr/ 86 Sr ratios of 0.735697–0.789683. There is no indication that equilibrium was reached between the CO 2 -rich thermal and mineral waters and the granitic rocks. The mean 87 Sr/ 86 Sr ratio of the thermal and mineral waters (0.722419) is similar to the Sr isotopic ratios of the plagioclases of the granitic rocks (0.71261–0.72087). The spatial distribution of Sr isotope and geochemical signatures of waters and the host rocks suggests that the thermal and mineral waters circulate in similar but not the same hydrogeological system. Results from this study could be used to evaluate the applicability of this isotope approach in other hydrogeologic investigations.

Trends in (LaMnO3)n/(SrTiO3)m superlattices with varying layer thicknesses

KAUST Repository

Jilili, J.

2015-09-01

We investigate the thickness dependence of the structural, electronic, and magnetic properties of (LaMnO3)n/(SrTiO3)m (n, m = 2, 4, 6, 8) superlattices using density functional theory. The electronic structure turns out to be highly sensitive to the onsite Coulomb interaction. In contrast to bulk SrTiO3, strongly distorted O octahedra are observed in the SrTiO3 layers with a systematic off centering of the Ti atoms. The systems favour ferromagnetic spin ordering rather than the antiferromagnetic spin ordering of bulk LaMnO3 and all show half-metallicity, while a systematic reduction of the minority spin band gaps as a function of the LaMnO3 and SrTiO3 layer thicknesses originates from modifications of the Ti dxy states.

A high 87Sr 86Sr mantle source for low alkali tholeiite, northern Great Basin

Science.gov (United States)

Mark, R.K.; Lee, Hu C.; Bowman, H.R.; Asaro, F.; McKee, E.H.; Coats, R.R.

1975-01-01

Olivine tholeiites, the youngest Tertiary units (about 8-11 m.y. old) at five widely spaced localities in northeastern Nevada, are geologically related to the basalts of the Snake River Plain, Idaho, to the north and are similar in major element and alkali chemistry to mid-ocean ridge basalts (MORB) and island arc tholeiites. The measured K (1250-3350 ppm), Rb (1??9-6??2 ppm) and Sr (140-240 ppm) concentrations overlap the range reported for MORB. Three of the five samples have low, unfractionated rare earth element (REE) patterns, the other two show moderate light-REE enrichment. Barium concentration is high and variable (100-780 ppm) and does not correlate with the other LIL elements. The rocks have 87Sr/86Sr = 0??7052-0??7076, considerably higher than MORB (~0??702-0??703). These samples are chemically distinct (i.e. less alkalic) from the olivine tholeiites from the adjacent Snake River Plain, but their Sr isotopic compositions are similar. They contain Sr that is distinctly more radiogenic than the basalts from the adjacent Great Basin. About 10 b.y. would be required for the mean measured Rb/Sr (~ 0??02) of these samples to generate, in a closed system, the radiogenic Sr they contain. The low alkali content of these basalts makes crustal contamination an unlikely mechanism. If the magma is uncontaminated, the time-averaged Rb/Sr of the source material must have been ~0??04. A significant decrease in Rb/Sr of the source material (a factor 2??) thus most probably occurred in the relatively recent (1??09 yr) past. Such a decrease of Rb/Sr in the mantle could accompany alkali depletion produced by an episode of partial melting and magma extraction. In contrast, low 87Sr 86Sr ratios indicate that the source material of the mid-ocean ridge basalts may have been depleted early in the Earth's history. ?? 1975.

The surface renewal method for better spatial resolution of evapotranspiration measurements

Science.gov (United States)

Suvocarev, K.; Fischer, M.; Massey, J. H.; Reba, M. L.; Runkle, B.

2017-12-01

Evaluating feasible irrigation strategies when water is scarce requires measurements or estimations of evapotranspiration (ET). Direct observations of ET from agricultural fields are preferred, and micrometeorological methods such as eddy covariance (EC) provide a high quality, continuous time series of ET. However, when replicates of the measurements are needed to compare irrigation strategies, the cost of such experiments is often prohibitive and limits experimental scope. An alternative micrometeorological approach to ET, the surface renewal (SR) method, may be reduced to a thermocouple and a propeller anemometer (Castellvi and Snyder, 2009). In this case, net radiation, soil and sensible heat flux (H) are measured and latent heat flux (an energy equivalent for ET) is estimated as the residual of the surface energy-balance equation. In our experiment, thermocouples (Type E Fine-Wire Thermocouple, FW3) were deployed next to the EC system and combined with mean horizontal wind speed measurements to obtain H using SR method for three weeks. After compensating the temperature signal for non-ideal frequency response in the wavelet half-plane and correcting the sonic anemometer for the flow distortion (Horst et al., 2015), the SR H fluxes compared well to those measured by EC (r2 = 0.9, slope = 0.92). This result encouraged us to install thermocouples over 16 rice fields under different irrigation treatments (continuous cascade flood, continuous multiple inlet rice irrigation, alternate wetting and drying, and furrow irrigation). The EC measurements with net radiometer and soil heat flux plates are deployed at three of these fields to provide a direct comparison. The measurement campaign will finish soon and the data will be processed to evaluate the SR approach for ET estimation. The results will be used to show better spatial resolution of ET measurements to support irrigation decisions in agricultural crops.

Renewable enthusiasm

International Nuclear Information System (INIS)

Duffin, Tony

2000-01-01

A reduction in energy consumption by the energy intensive sectors will be rewarded by a tax credit. The advantages of renewable sources of energy in terms of reducing emissions of carbon dioxide are extolled. The Government will reward the use of renewables through exemption from the Climate Change Levy. Many major companies are now committed to renewables and Shell predict that 50% of world energy will come from renewables by 2050. World-wide there is now 10,000 MW of installed wind power and the annual rate of growth is more than 20%. Other renewables such as biomass, energy from waste, solar power, hydropower, wind power and tidal power are discussed. The Government would like to see 10% of the UK's electricity coming from renewables by 2010. (UK)

SURFACE ENERGY BALANCE OVER ORANGE ORCHARD USING SURFACE RENEWAL ANALYSIS

Directory of Open Access Journals (Sweden)

Salvatore Barbagallo

2009-12-01

Full Text Available Reliable estimation of surface sensible and latent heat flux is the most important process to appraise energy and mass exchange among atmosphere and biosphere. In this study the surface energy fluxes were measured over an irrigated orange orchard during 2005-2008 monitoring periods using a Surface Renewal- Energy Balance approach. The experimental area is located in a representative orchard growing area of eastern Sicily (Italy. The performance of Surface Renewal (SR analysis for estimating sensible heat flux (H was analysed and evaluated in terms of correlation with H fluxes from the eddy covariance (EC method. Study revealed that the mean available energy (RN- G and latent heat flux (LE were of about 300 W m-2 and 237 W m-2, respectively, during dry periods and unstable-case atmospheric conditions. The estimated crop coefficient Kc values for the orchard crop averaged close to 0.80, which is considerably higher than previous FAO studies that found the value to be 0.65 for citrus with 70% of ground cover. The intercepted photosynthetically active radiation (LI PAR by the crop was measured and relationships between LAI and crop coefficient (Kc were established.

Vacancy induced metallicity at the CaHfO3/SrTiO3 interface

KAUST Repository

Nazir, Safdar

2011-03-31

Density functional theory is used to study the electronic properties of the oxide heterointerfaceCaHfO3/SrTiO3. Structural relaxation is carried out with and without O vacancies. As compared to related interfaces, strongly reduced octahedral distortions are found. Stoichiometric interfaces between the wide band gap insulatorsCaHfO3 and SrTiO3 turn out to exhibit an insulating state. However, interface metallicity is introduced by O vacancies, in agreement with experiment. The reduced octahedral distortions and necessity of O deficiency indicate a less complicated mechanism for the creation of the interfacial electron gas.

Vacancy induced metallicity at the CaHfO3/SrTiO3 interface

KAUST Repository

Nazir, Safdar; Pulikkotil, J. J.; Schwingenschlö gl, Udo; Singh, Nirpendra

2011-01-01

Density functional theory is used to study the electronic properties of the oxide heterointerfaceCaHfO3/SrTiO3. Structural relaxation is carried out with and without O vacancies. As compared to related interfaces, strongly reduced octahedral distortions are found. Stoichiometric interfaces between the wide band gap insulatorsCaHfO3 and SrTiO3 turn out to exhibit an insulating state. However, interface metallicity is introduced by O vacancies, in agreement with experiment. The reduced octahedral distortions and necessity of O deficiency indicate a less complicated mechanism for the creation of the interfacial electron gas.

Performance comparison of renewable incentive schemes using optimal control

International Nuclear Information System (INIS)

Oak, Neeraj; Lawson, Daniel; Champneys, Alan

2014-01-01

Many governments worldwide have instituted incentive schemes for renewable electricity producers in order to meet carbon emissions targets. These schemes aim to boost investment and hence growth in renewable energy industries. This paper examines four such schemes: premium feed-in tariffs, fixed feed-in tariffs, feed-in tariffs with contract for difference and the renewable obligations scheme. A generalised mathematical model of industry growth is presented and fitted with data from the UK onshore wind industry. The model responds to subsidy from each of the four incentive schemes. A utility or ‘fitness’ function that maximises installed capacity at some fixed time in the future while minimising total cost of subsidy is postulated. Using this function, the optimal strategy for provision and timing of subsidy for each scheme is calculated. Finally, a comparison of the performance of each scheme, given that they use their optimal control strategy, is presented. This model indicates that the premium feed-in tariff and renewable obligation scheme produce the joint best results. - Highlights: • Stochastic differential equation model of renewable energy industry growth and prices, using UK onshore wind data 1992–2010. • Cost of production reduces as cumulative installed capacity of wind energy increases, consistent with the theory of learning. • Studies the effect of subsidy using feed-in tariff schemes, and the ‘renewable obligations’ scheme. • We determine the optimal timing and quantity of subsidy required to maximise industry growth and minimise costs. • The premium feed-in tariff scheme and the renewable obligations scheme produce the best results under optimal control

Gestalt Theory and Instructional Design.

Science.gov (United States)

Moore, Patrick; Fitz, Chad

1993-01-01

Offers a brief overview of Gestalt theory. Shows how six Gestalt principles (proximity, closure, symmetry, figure-ground segregation, good continuation, and similarity) can be applied to improve a reader's comprehension of a badly designed instruction module that uses several graphics. (SR)

87Sr/86Sr isotope fingerprinting of Scottish and Icelandic migratory shorebirds

International Nuclear Information System (INIS)

Evans, Jane; Bullman, Rhys

2009-01-01

Biosphere Sr isotope composition data from Iceland and Scotland suggest that terrestrially feeding birds from these two countries will have significantly different 87 Sr/ 86 Sr isotope composition in their tissues. The aim of this study is to test if these differences can be measured within the bone and feather of migratory wading birds, who feed terrestrially as juveniles, thus providing a provenance tool for these birds. The study shows that birds can be distinguished on the basis of the Sr isotope composition of their bone. The field for Icelandic birds is defined by data from juvenile common redshank (Tringa totanus) and whimbrel (Numenius phaeopus) which give 0.7056 ± 0.0012, (2σ, n = 7). The majority of Scottish birds in this study are from coastal regions and have a signature close to that of seawater of 0.7095 ± 0.0006 (2σ, n = 9). The Sr ratios in the body tissue of these two populations of all Icelandic and Scottish adult and juvenile birds analysed are significantly different (p 87 Sr/ 86 Sr values as high as 0.7194 which reflect their non-marine diet. Icelandic redshank (Tringa totanus robusta) that have flown to Scotland and returned to Iceland show the effect of the Scottish contribution to their diet with elevated values of 0.7086 ± 0.0004, (2σ, n = 6). Redshank found in Scotland that cannot be classified on the basis biometric analysis are shown to be of Icelandic origin and analysis of the primary feathers from two birds demonstrates that isotope variation between feathers could be used to track changes in diet related to the timing of individual feather growth.

Transport of Sr 2+ and SrEDTA 2- in partially-saturated and heterogeneous sediments

Science.gov (United States)

Pace, M. N.; Mayes, M. A.; Jardine, P. M.; McKay, L. D.; Yin, X. L.; Mehlhorn, T. L.; Liu, Q.; Gürleyük, H.

2007-05-01

Strontium-90 has migrated deep into the unsaturated subsurface beneath leaking storage tanks in the Waste Management Areas (WMA) at the U.S. Department of Energy's (DOE) Hanford Reservation. Faster than expected transport of contaminants in the vadose zone is typically attributed to either physical hydrologic processes such as development of preferential flow pathways, or to geochemical processes such as the formation of stable, anionic complexes with organic chelates, e.g., ethylenediaminetetraacetic acid (EDTA). The goal of this paper is to determine whether hydrological processes in the Hanford sediments can influence the geochemistry of the system and hence control transport of Sr 2+ and SrEDTA 2-. The study used batch isotherms, saturated packed column experiments, and an unsaturated transport experiment in an undisturbed core. Isotherms and repacked column experiments suggested that the SrEDTA 2- complex was unstable in the presence of Hanford sediments, resulting in dissociation and transport of Sr 2+ as a divalent cation. A decrease in sorption with increasing solid:solution ratio for Sr 2+ and SrEDTA 2- suggested mineral dissolution resulted in competition for sorption sites and the formation of stable aqueous complexes. This was confirmed by detection of MgEDTA 2-, MnEDTA 2-, PbEDTA 2-, and unidentified Sr and Ca complexes. Displacement of Sr 2+ through a partially-saturated undisturbed core resulted in less retardation and more irreversible sorption than was observed in the saturated repacked columns, and model results suggested a significant reservoir (49%) of immobile water was present during transport through the heterogeneous layered sediments. The undisturbed core was subsequently disassembled along distinct bedding planes and subjected to sequential extractions. Strontium was unequally distributed between carbonates (49%), ion exchange sites (37%), and the oxide (14%) fraction. An inverse relationship between mass wetness and Sr suggested that

Multi-level lobbying in the EU: The case of the Renewables Directive and the German energy industry

Energy Technology Data Exchange (ETDEWEB)

Ydersbond, Inga Margrete

2012-11-01

This study examines the lobbying strategies employed by the interest organizations of Germany's energy industries in the process leading up to the EU's Renewable Energy Directive. How did they lobby, and what does this reveal about their perceptions of power relations in the EU? This report focuses on the most controversial part of the Directive: legal prescriptions for support mechanisms to increase the production of renewable energy in Europe. The utilities and the renewables industries disagreed deeply, with the utilities industry favouring an EU-wide green certificate scheme, while the renewables industry pressed for national feed-in tariffs. Nine interest organizations representing these sectors, five German and four at the EU level, serve as cases in this study. Expectations as to lobbying behaviour based on the two theories/theory perspectives of liberal intergovernmentalism (LI) and multi-level governance (MLG) are formulated and tested in a most-likely case design. Result: observations are better described by the MLG perspective than by LI.(auth)

Multi-level lobbying in the EU: The case of the Renewables Directive and the German energy industry

Energy Technology Data Exchange (ETDEWEB)

Ydersbond, Inga Margrete

2012-11-01

This study examines the lobbying strategies employed by the interest organizations of Germany's energy industries in the process leading up to the EU's Renewable Energy Directive. How did they lobby, and what does this reveal about their perceptions of power relations in the EU? This report focuses on the most controversial part of the Directive: legal prescriptions for support mechanisms to increase the production of renewable energy in Europe. The utilities and the renewables industries disagreed deeply, with the utilities industry favouring an EU-wide green certificate scheme, while the renewables industry pressed for national feed-in tariffs. Nine interest organizations representing these sectors, five German and four at the EU level, serve as cases in this study. Expectations as to lobbying behaviour based on the two theories/theory perspectives of liberal intergovernmentalism (LI) and multi-level governance (MLG) are formulated and tested in a most-likely case design. Result: observations are better described by the MLG perspective than by LI.(auth)

Renewable energy

DEFF Research Database (Denmark)

Olsen, Birgitte Egelund

2016-01-01

Renewable energy projects are increasingly confronted by local opposition, which delays and sometimes even prevents their implementation. This reflects the frequent gap between support for the general idea of renewables as a strategy for reducing carbon emissions, and acceptance of renewable energy...

The randomly renewed general item and the randomly inspected item with exponential life distribution

International Nuclear Information System (INIS)

Schneeweiss, W.G.

1979-01-01

For a randomly renewed item the probability distributions of the time to failure and of the duration of down time and the expectations of these random variables are determined. Moreover, it is shown that the same theory applies to randomly checked items with exponential probability distribution of life such as electronic items. The case of periodic renewals is treated as an example. (orig.) [de

Comment: The Economics of Interdependent Renewable and Non-renewable Resources revisited.

OpenAIRE

Viktoria Kahui; Claire W. Armstrong

2009-01-01

This work expands upon Swallow's theoretical analysis of interactions between renewable and non-renewable resources. In this comment the interaction is such that the renewable resource prefers the non-renewable environment, as opposed to SwallowÕs (op cit) case of the non-renewable environment being essential to the renewable resource. We find that this difference strongly affects the results, and makes the resources change from being complements to being substitutes, i.e. in the essential ca...

Electronic characterization of LaAlO{sub 3}-SrTiO{sub 3} interfaces by scanning tunneling spectroscopy; Elektronische Charakterisierung von LaAlO{sub 3}-SrTiO{sub 3}-Grenzflaechen mittels Rastertunnelspektroskopie

Energy Technology Data Exchange (ETDEWEB)

Breitschaft, Martin

2010-10-22

When LaAlO{sub 3} is epitaxially grown on TiO{sub 2}-terminated SrTiO{sub 3}, an electrically conducting interface is generated. In this respect, the physical properties of the interface differ substantially from those of both LaAlO{sub 3} and SrTiO{sub 3}, which are electrically insulating in bulk form. This dissertation looks into the question of the microscopic structure of the conducting two-dimensional interface electron system. Comparing the electronic density of states of LaAlO{sub 3}-SrTiO{sub 3} interfaces measured by scanning tunneling spectroscopy with results of density functional theory, the interface electron system is found to be substantially coined by the hosting transition metal lattices. The comparison yields a detailed picture of the microscopic structure of the interface electron system. (orig.)

External Benefit Evaluation of Renewable Energy Power in China for Sustainability

Directory of Open Access Journals (Sweden)

Huiru Zhao

2015-04-01

Full Text Available China’s renewable energy power has developed rapidly in recent years. Evaluating the external benefits of renewable energy power can provide a reference for the Chinese government to set diverse development goals and to implement differentiated supporting policies for different renewable energy power types, which can promote their sustainable development. In this paper, a hybrid MCDM method was applied to evaluate the external benefits of China’s renewable energy power. Firstly, the impacts of renewable energy power accessing the power grid for multiple stakeholders in the electric power system were analyzed. Secondly, the external benefit evaluation index system for renewable energy power was built from the economic, social and environmental factors, based on the concept of sustainability. Then, the basic theory of the hybrid MCDM method employed in this paper was introduced in two parts: the superiority linguistic ratings and entropy weighting method for index weight determination and the fuzzy grey relation analysis for ranking alternatives. Finally, the external benefits of wind power, solar PV power and biomass power were evaluated. Taking a regional electric power system as an example, the results show that PV power has the greatest external benefit, followed by wind power and biomass power. Therefore, more policies supporting PV power should be put in place to promote the harmonious and sustainable development of the whole renewable energy power industry.

Automation of sample processing for ICP-MS determination of 90Sr radionuclide at ppq level for nuclear technology and environmental purposes.

Science.gov (United States)

Kołacińska, Kamila; Chajduk, Ewelina; Dudek, Jakub; Samczyński, Zbigniew; Łokas, Edyta; Bojanowska-Czajka, Anna; Trojanowicz, Marek

2017-07-01

90 Sr is a widely determined radionuclide for environmental purposes, nuclear waste control, and can be also monitored in coolants in nuclear reactor plants. In the developed method, the ICP-MS detection was employed together with sample processing in sequential injection analysis (SIA) setup, equipped with a lab-on-valve with mechanized renewal of sorbent bed for solid-phase extraction. The optimized conditions of determination included preconcentration of 90 Sr on cation-exchange column and removal of different type of interferences using extraction Sr-resin. The limit of detection of the developed procedure depends essentially on the configuration of the employed ICP-MS spectrometer and on the available volume of the sample to be analyzed. For 1L initial sample volume, the method detection limit (MDL) value was evaluated as 2.9ppq (14.5BqL -1 ). The developed method was applied to analyze spiked river water samples, water reference materials, and also simulated and real samples of the nuclear reactor coolant. Copyright © 2016 Elsevier B.V. All rights reserved.

Succession and Renewal in Urban Neighborhoods: The Case of Coney Island

Directory of Open Access Journals (Sweden)

Raymond M. Weinstein

2007-10-01

Full Text Available Sociologists for some time have used the concepts of succession and renewal to describe two different, but sometimes complementary, processes of neighborhood change in urban areas. Coney Island has long been famous as an amusement area popular in New York City, but today the area has fallen on hard times. Developers want to tear down the amusement area of Coney Island and replace it with condos for the well-to-do. This process is discussed in light of classic sociological theories of urban change and renewal.

Effect of In-Doping on Electronic Structure and Optical Properties of Sr2TiO4

International Nuclear Information System (INIS)

Jiang-Ni, Yun; Zhi-Yong, Zhang; Jun-Feng, Yan; Fu-Chun, Zhang

2009-01-01

The effect of In doping on the electronic structure and optical properties of Sr 2 TiO 4 is investigated by a first-principles calculation of plane wave ultrasoft pseudopotentials based on density functional theory. The calculated results reveal that corner-shared TiO 6 octahedra dominate the main electronic properties of Sr 2 TiO 4 and the covalency of the Ti–O(1) bond in the ab plane is stronger than that of the Ti–O(2) bond along the c-axis. After In doping, there is a little lattice expansion in Sr 2 In 0.125 Ti 0.875 O 4 , and the interaction between the Ti–O bond near the impurity In atom is weakened. The binding energies of Sr 2 TiO 4 and Sr 2 In 0.125 Ti 0.875 O 4 , estimated from the electronic structure calculations indicate that the crystal structure of Sr 2 In 0.125 Ti 0.875 O 4 is still stable after doping, but its stability is lower than that of undoped Sr 2 TiO 4 . Moreover, the valence bands (VBs) of the Sr 2 In 0.125 Ti 0.875 O 4 , system consist of O 2p and In 4d states, and the mixing of O 2p and In 4d states makes the top VBs shift significantly to high energies, resulting in visible light absorption. The adsorption of visible light is of practical importance for the application of Sr 2 TiO 4 as a photocatalyst. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

Renewable Energy: Policy Considerations for Deploying Renewables

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

This information paper accompanies the IEA publication Deploying Renewables 2011: Best and Future Policy Practice (IEA, 2011a). It provides more detailed data and analysis on policies for Deploying Renewables, and is intended to complement the main publication. It provides an account of the strategic drivers underpinning renewable energy (RE) technology deployment (energy security, economic development and environment protection) and assesses RE technologies with respect to these drivers, including an estimate of GHG emissions reductions due to RE technologies. The paper also explores the different barriers to deploying renewables at a given stage of market maturity and discusses what tools policy makers can avail of to succeed in removing deployment barriers. An additional topical highlight explores the challenges associated with accelerating the diffusion of RE technologies in developing countries.

RENEWAL OF BASIC LAWS AND PRINCIPLES FOR POLAR CONTINUUM THEORIES (Ⅱ)-MICROMORPHIC CONTINUUM THEORY AND COUPLE STRESS THEORY

Institute of Scientific and Technical Information of China (English)

戴天民

2003-01-01

The purpose is to reestablish the balance laws of momentum, angular momentumand energy and to derive the corresponding local and nonlocal balance equations formicromorphic continuum mechanics and couple stress theory. The desired results formicromorphic continuum mechanics and couple stress theory are naturally obtained via directtransitions and reductions from the coupled conservation law of energy for micropolarcontinuum theory, respectively. The basic balance laws and equation s for micromorphiccontinuum mechanics and couple stress theory are constituted by combining these resultsderived here and the traditional conservation laws and equations of mass and microinertiaand the entropy inequality. The incomplete degrees of the former related continuum theoriesare clarified. Finally, some special cases are conveniently derived.

Ac susceptibility studies on Bi-Sr-Ca-Cu-O system

International Nuclear Information System (INIS)

Chakravarti, Arani; Mukherjee, C.D.; Ranganathan, R.; Chatterjee, N.; Raychaudhuri, A.K.

1991-01-01

We report the low a.c. susceptibility data χ'(T,Hsub(rms)), χsup(double inverted commas)(T,Hsub(rms)) for the newly prepared superconducting system Bi x Sr 4 Ca 2 Cu 4 O y (x=0.5, 1.0 and 1.5) containing Bi at concentrations lower than that in the conventional Bi-based system. The experimental results are discussed in the light of existing theories. (author). 10 refs., 3 figs

Values of Land and Renewable Resources in a Three-Sector Economic Growth Model

Directory of Open Access Journals (Sweden)

Zhang Wei-Bin

2015-04-01

Full Text Available This paper studies dynamic interdependence of capital, land and resource values in a three sector growth model with endogenous wealth and renewable resources. The model is based on the neoclassical growth theory, Ricardian theory and growth theory with renewable resources. The household’s decision is modeled with an alternative approach proposed by Zhang two decades ago. The economic system consists of the households, industrial, agricultural, and resource sectors. The model describes a dynamic interdependence between wealth accumulation, resource change, and division of labor under perfect competition. We simulate the model to demonstrate the existence of a unique stable equilibrium point and plot the motion of the dynamic system. The study conducts comparative dynamic analysis with regard to changes in the propensity to consume resources, the propensity to consume housing, the propensity to consume agricultural goods, the propensity to consume industrial goods, the propensity to save, the population, and the output elasticity of capital of the resource sector.

Thermodynamic assessment of the Pb-Sr system

Directory of Open Access Journals (Sweden)

Zhang H.

2017-01-01

Full Text Available The Pb-Sr system has been critically reviewed and modeled by means of the CALPHAD (CALculation of PHAse Diagrams approach. It contains seven stoichiometric compounds, i.e. SrPb3, Sr3Pb5, Sr2Pb3, SrPb, Sr5Pb4, Sr5Pb3 and Sr2Pb, in which the SrPb3 and Sr2Pb phases melt congruently, and the other five phases form via peritectic reactions. The enthalpies of formation for the intermetallic compounds at 0 K are provided by first-principles calculations. The liquid, fcc and bcc phases are modeled as substitutional solution phases. Both Redlich-Kister and exponential polynomials are used to describe the excess Gibbs energy of the liquid. Two sets of self-consistent thermodynamic parameters are obtained by considering reliable experimental data and the computed enthalpies of formation. Comprehensive comparisons between the calculated and measured phase diagram and thermodynamic data show that the experimental information is satisfactorily accounted for by the present thermodynamic description.

System of Sr(NO2)2-Sr(OH)2-H2O at 25 deg C

International Nuclear Information System (INIS)

Popova, T.B.; Berdyukova, V.A.; Khutsistova, F.M.

1990-01-01

Sr(NO 2 ) 2 -Sr(OH) 2 -H 2 O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO 2 ) 2 xSr(OH) 2 x8H 2 O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained

C, Sr and Sr isotopic composition on probable vendian- tommotian carbonate sequences in Nw Argentina

International Nuclear Information System (INIS)

Sial, A. N.; Ferreira, V.P; Toselli, A.J.; Acenolaza, F.G; Pimentel, M.M; Parada, M.A; Alonso, R.N

2001-01-01

C-isotope stratigraphy is one of the most powerfool tools in Precambrian chronostratigraphy, especially when sediments lack recognizable animal fossils. The δ 13 C secular variation curves for marine carbonates in the Neoproterozoic-Cambrian interval show strong positive-negative excursions, several of them interpreted as the stratigraphic position of ancient ice ages (Hoffman et al. 1998). The Sr isotope composition of the seawater for this age interval is characterized by a continuous increase of 87 Sr/ 86 Sr that is interrupted, several times, by sharp rises, which represent important changes in the Earth history (Montanez et al. 2000). Only limited data on the behavior of C and Sr isotopes in carbonates are available in South America. We examine here carbonate sequences from the Argentine Precordillera, San Juan province, and from other carbonate sequences in NW Argentina that could be, potentially, proxies for the Precambrian-Cambrian transition. We have studied their δ 13 C and 87 Sr/ 86 Sr chemostratigraphy and compare it to global C and Sr isotope secular variation curves for this time span. This study aims to improve the relatively coarse stratigraphic resolution provided only by the study of the fossil record in some of the carbonate successions under consideration (au)

On the “alpha-phase” of Ca2−xSrxMnO4 and extending the chemistry of Sr7−yCayMn4O15 to y>1

International Nuclear Information System (INIS)

Craddock, Sarah; Senn, Mark S.

2017-01-01

There has been renewed interest in the Ruddlesden-Popper phase (n=2) of composition Ca n+1 Mn n O 3 n+1 in the light of recent research that has highlighted the nature of the improper ferroelectric ground state, which arises due to the couplings between specific combinations of MnO 6 octahedral rotations and tilts. A fruitful route to control these octahedral degrees of freedom, and hence such desired physical properties, is through chemical substitution on the A–site cation i.e. Ca 2−x Sr x MnO 4 for n =1, and in light of this, we have reinvestigated the chemistry of this solid solution. Here we focus on a common impurity phase observed during this synthesis which has been termed the “alpha-phase” in the literature. We show that this impurity phase is actually comprised mainly of a structure related to Sr 7 Mn 4 O 15 but is found here with significantly higher Ca substitution than previously believed possible. Sr 7 Mn 4 O 15 is an interesting structural type in its own right, but has been mainly overlooked to date, exhibiting interesting physics related to low dimensional magnetic ordering and dimer interactions, and we show here that the structural type is a likely candidate for exhibiting a multiferroic ground state. The prospect of being able to tune the lattice and the exchange interactions through further chemical substitution is likely to lead to a renewed interest in this material. - Graphical abstract: Extending the chemistry of Sr 7−y Ca y Mn 4 O 15 beyond y>1, revealing highly anisotropic cation ordering and tunable magnetic properties. - Highlights: • Chemistry of the unique structural type Sr 7 Mn 4 O 15 is extended to high Ca concentrations. • Cation occupancy model is determined, showing highly anisotropic solubility of Ca on the 7 unique Sr crystallographic sites. • Anomalies in the magnetic susceptibility data are discussed with reference to symmetry arguments pointing towards a possible novel multiferroic mechanism in this material.

Talking Renewables; A renewable energy primer for everyone

Science.gov (United States)

Singh, Anirudh

2018-03-01

This book provides a clear and factual picture of the status of renewable energy and its capabilities today. The book covers all areas of renewable energy, starting from biomass energy and hydropower and proceeding to wind, solar and geothermal energy before ending with an overview of ocean energy. The book also explores how the technologies are being implemented today and takes a look at the future of renewable energy.

Measurement of resonance integral of the 90Sr(n,γ)91Sr reaction

International Nuclear Information System (INIS)

Nakamura, Shoji; Furutaka, Kazuyoshi; Wada, Hiroaki; Katoh, Toshio; Harada, Hideo; Fujii, Toshiyuki; Yamana, Hajimu

2001-01-01

To obtain fundamental data for research on nuclear transmutation method of radioactive wastes, the resonance integral (I 0 ) of the 90 Sr(n,γ) 91 Sr reaction was measured with an activation method. (author)

The renewable energy development framework - II. The foundations of renewable energy development: Economic foundations of renewable energies; International foundations of renewable energies; European foundations of renewable energy development; Foundations of renewable energy development in internal law

International Nuclear Information System (INIS)

Combes Motel, Pascale; Thebaut, Matthieu; Loic Grard; Michallet, Isabelle

2012-01-01

A first article analysis the reasons for the development of renewable energies (economic and environmental reasons, European commitments in terms of production objectives), how these renewable energies can be developed (acceptation by the population, administrative, technological, and financial constraints, political instruments related to market, taxes and purchase prices). A second article proposes a discussion about the way international law deals with renewable energies as far as texts as well as actors are concerned. The third article describes the European ambitions regarding renewable energies as a product of national perspectives (national action plans and projects) as well as of European perspectives (financing, integrated actions). The last article presents and comments various legal texts dealing with the development of renewable energies in France (texts concerning the right to energy, the environment law, planning tools, incentive measures)

Spectroscopic properties of Ho{sup 3+}-doped K-Sr-Al phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Linganna, K.; Rathaiah, M.; Venkatramu, V. [Yogi Vemana University, Department of Physics, Kadapa (India); Jayasankar, C.K. [Sri Venkateswara University, Department of Physics, Tirupati (India)

2014-05-15

Trivalent holmium-doped K-Sr-Al phosphate glasses (P{sub 2}O{sub 5}-K{sub 2}O-SrO-Al{sub 2}O{sub 3}-Ho{sub 2}O{sub 3}) were prepared, and their spectroscopic properties have been evaluated using absorption, emission, and excitation measurements. The Judd-Ofelt theory has been used to derive spectral intensities of various absorption bands from measured absorption spectrum of 1.0 mol% Ho{sub 2}O{sub 3}-doped K-Sr-Al phosphate glass. The Judd-Ofelt intensity parameters (Ω{sub λ}, x 10{sup -20} cm{sup 2}) have been determined of the order of Ω{sub 2} = 11.39, Ω{sub 4} = 3.59, and Ω{sub 6} = 2.92, which in turn used to derive radiative properties such as radiative transition probability, radiative lifetime, branching ratios, etc. for excited states of Ho{sup 3+} ions. The radiative lifetimes for the {sup 5}F{sub 4}, {sup 5}S{sub 2}, and {sup 5}F{sub 5} levels of Ho{sup 3+} ions are found to be 169, 296, and 317 μs, respectively. The stimulated emission cross-section for 2.05-μm emission was calculated by the McCumber theory and found to be 9.3 x 10{sup -21} cm{sup 2}. The wavelength-dependent gain coefficient with population inversion rate has been evaluated. The results obtained in the titled glasses are discussed systematically and compared with other Ho{sup 3+}-doped systems to assess the possibility for visible and infrared device applications. (orig.)

A Multidimensional Measure of Trait Anxiety: The S-R Inventory of General Trait Anxiousness

Science.gov (United States)

Endler, Norman S.; Okada, Marilyn

1975-01-01

The S-R Inventory of General Trait Anxiousness was administered to samples of normal youth, normal adult, neurotic, and psychotic subjects. The practical and theoretical uses of the inventory are discussed, and it is specifically indicated how the inventory could be used to extend the Speilberger state-trait anxiety theory. (Author)

Equilibrium Transitions from Non Renewable Energy to Renewable Energy under Capacity Constraints

OpenAIRE

Amigues, Jean-Pierre; Ayong Le Kama, Alain; Moreaux, Michel

2013-01-01

We study the transition between non-renewable and renewable energy sources with adjustment costs over the production capacity of renewable energy. Assuming constant variable marginal costs for both energy sources, convex adjustment costs and a more expensive renewable energy, we show the following. With sufficiently abundant non-renewable energy endowments, the dynamic equilibrium path is composed of a first time phase of only non-renewable energy use followed by a transition phase substituti...

Electronic and structural properties of Sr2YSbO6

International Nuclear Information System (INIS)

Ortiz-Diaz, O.; Jairo Arbey Rodriguez, M.; Fajardo, F.; Landinez Tellez, D.A.; Roa-Rojas, J.

2007-01-01

The electronic and structural properties of the cubic perovskite Sr 2 YSbO 6 were predicted from ab initio calculations. Such properties were obtained using the density functional theory (DFT). The full-potential (linearized) augmented plane-wave ((L)APW) method was used, as it is implemented in wien2k code. We have optimized the volume of the unitary cell and the internal x parameter. The lattice constant (a) and x determine some length bonds. We have found that a=8.405 A, x=0.26177, and the bond lengths Y-O and Sb-O are 2.20 and 2.00 A, respectively. Additionally, Sr 2 YSbO 6 was prepared experimentally by the solid-state reaction method using stoichiometric mixtures of high purity (99.99%). By means of X-ray and Rietveld analysis, the main structural features were determined. The experimental lattice parameter is a=8.249 A, which differs about 1.9% of the value obtained using DFT. The bulk modulus is ∼133 GPa, which is not measured experimentally. DFT predicts that Sr 2 YSbO 6 is an indirect semiconductor and magnetic behavior does not have to be expected because at Fermi level the dominant orbitals are p-oxygen. The gap of the material is at least 2.5 eV

FEP report for the safety assessment SR-Site

Energy Technology Data Exchange (ETDEWEB)

2010-12-15

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

FEP report for the safety assessment SR-Site

International Nuclear Information System (INIS)

2010-12-01

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Site, and forms an important part of the reporting of the project. The main part of the work was conducted within the earlier safety assessment SR-Can, which was a preparatory stage for the SR-Site assessment. The overall objective of the FEP analysis and processing in both SR-Can and SR-Site included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The primary objective in SR-Site was to establish an SR-Site FEP catalogue within the framework of the SKB FEP database. This FEP catalogue was required to contain all FEPs that needed to be handled in SR-Site and is an update of the corresponding SR-Can FEP catalogue that was established for the SR-Can assessment. The starting point for the handling of FEPs in SR-Site was the SR-Can version of the SKB FEP database and associated SR-Can reports. The SR-Can version of the SKB FEP database includes the SR-Can FEP catalogue, as well as the sources for the identification of FEPs in SR-Can, namely the SR 97 processes and variables, Project FEPs in the NEA International FEP database version 1.2 and matrix interactions in the Interaction matrices developed for a deep repository of the KBS-3 type. Since the completion of the FEP work within SR-Can, an updated electronic version, version 2.1, of the NEA FEP database has become available. Compared with version 1.2 of the NEA FEP database, version 2.1 contains FEPs from two more projects. As part of SR-Site, all new Project FEPs in version 2.1 of the NEA FEP database have been mapped according to the methodology adopted in SR-Can resulting in an SR-Site version of the SKB FEP database. The SKB FEP

Renewable Energy

DEFF Research Database (Denmark)

Sørensen, Bent Erik

Bent Sorensen’s Renewable Energy: Physics, Engineering, Environmental Impacts, Economics and Planning, Fifth Edition, continues the tradition by providing a thorough and current overview of the entire renewable energy sphere. Since its first edition, this standard reference source helped put...... renewable energy on the map of scientific agendas. Several renewable energy solutions no longer form just a marginal addition to energy supply, but have become major players, with the promise to become the backbone of an energy system suitable for life in the sustainability lane. This volume is a problem...... structured around three parts in order to assist readers in focusing on the issues that impact them the most for a given project or question. PART I covers the basic scientific principles behind all major renewable energy resources, such as solar, wind, and biomass. PART II provides in-depth information...

Thermal infrared and microwave absorbing properties of SrTiO3/SrFe12O19/polyaniline nanocomposites

International Nuclear Information System (INIS)

Hosseini, Seyed Hossein; Zamani, Parisa; Mousavi, S.Y.

2015-01-01

Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO 3 /SrFe 12 O 19 /PANI exhibited electric and electromagnetic properties. • The SrTiO 3 /SrFe 12 O 19 /PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO 3 was synthesized as IR absorbent and core and then SrFe 12 O 19 as microwave absorbent was prepared on SrTiO 3 via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO 3 /SrFe 12 O 19 nanoparticles via in situ polymerization by multi core–shell structures (SrTiO 3 /SrFe 12 O 19 /PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the SrTiO 3 /SrFe 12 O 19 /PANI nanocomposites have good compatible

Changes in local surface structure and Sr depletion in Fe-implanted SrTiO{sub 3} (001)

Energy Technology Data Exchange (ETDEWEB)

Lobacheva, O., E-mail: olobache@gmail.com [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Yiu, Y.M. [Department of Chemistry, Western University, London, ON N6A 5B7 (Canada); Chen, N. [Canadian Light Source, Saskatoon, SK S7N 0X4 (Canada); Sham, T.K.; Goncharova, L.V. [Department of Physics and Astronomy, Western University, London, ON N6A 5B7 (Canada); Department of Chemistry, Western University, London, ON N6A 5B7 (Canada)

2017-01-30

Highlights: • Fe ion implantation of SrTiO{sub 3} and post-implantation results in formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase. • In Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase, Fe assumes Fe{sup 3+} oxidation state in the bulk and Fe{sup 2+} oxidation state in the near surface area. • FEFF9 calculations indicate that Fe ions can substitute both Ti and Sr sites. • Formation of Sr{sub 1-y}Ti{sub 1-x}Fe{sub x+y}O{sub 3-δ} phase is accompanied by Sr depletion in the near surface region. - Abstract: Local surface structure of single crystal strontium titanate SrTiO{sub 3} (001) samples implanted with Fe in the range of concentrations between 2 × 10{sup 14} to 2 × 10{sup 16} Fe/cm{sup 2} at 30 keV has been investigated. In order to facilitate Fe substitution (doping), implanted samples were annealed in oxygen at 350 °C. Sr depletion was observed from the near-surface layers impacted by the ion-implantation process, as revealed by Rutherford Backscattering Spectrometry (RBS), X-ray photoelectron spectroscopy (XPS), X-ray Absorption Near Edge Spectroscopy (XANES), and Atomic Force Microscopy (AFM). Hydrocarbon contaminations on the surface may contribute to the mechanisms of Sr depletion, which have important implications for Sr(Ti{sub 1-x}Fe{sub x})O{sub 3-δ} materials in gas sensing applications.

New aragonite 87Sr/86Sr records of Mesozoic ammonoids and approach to the problem of N, O, C and Sr isotope cycles in the evolution of the Earth

Science.gov (United States)

Zakharov, Yuri D.; Dril, Sergei I.; Shigeta, Yasunari; Popov, Alexander M.; Baraboshkin, Eugenij Y.; Michailova, Irina A.; Safronov, Peter P.

2018-02-01

New Sr isotope data from well-preserved aragonite ammonoid shell material from the Mesozoic are compared with that from a living Nautilus shell. The prominent negative Sr isotope excursions known from the Middle Permian, Jurassic and Cretaceous probably have their origins in intensive plate tectonic activity, followed by enhanced hydrothermal activity at the mid-ocean ridges (mantle volcanism) which supplied low radiogenic Sr to seawater. The maximum positive (radiogenic) shift in the lower Mesozoic Sr isotope curve (Lower Triassic peak) was likely caused by a significant expansion of dry land surfaces (Dabie-Sulu Triassic orogeny) and their intensive silicate weathering in conditions of extreme warming and aridity in the very end of the Smithian, followed by warm and humid conditions in the late Spathian, which apparently resulted in a significant oceanic input of radiogenic Sr through riverine flux. The comparatively high 87Sr/86Sr ratio obtained from the living Nautilus shell is probably a function of both the Alpine orogeny, which was accompanied by significant continental weathering and input of radiogenic Sr to the oceans, and the weakening of mantle volcanism.

Over-expression of SR-cyclophilin, an interaction partner of nuclear pinin, releases SR family splicing factors from nuclear speckles

International Nuclear Information System (INIS)

Lin, C.-L.; Leu, Steve; Lu, M.-C.; Ouyang Pin

2004-01-01

Pre-mRNA splicing takes place within a dynamic ribonucleoprotein particle called the spliceosome and occurs in an ordered pathway. Although it is known that spliceosome consists of five small nuclear RNAs and at least 50 proteins, little is known about how the interaction among the proteins changes during splicing. Here we identify that SR-cyp, a Moca family of nuclear cyclophilin, interacts and colocalizes with nuclear pinin (pnn), a SR-related protein involving in pre-mRNA splicing. Nuclear pnn interacts with SR-cyp via its C-terminal RS domain. Upon SR-cyp over-expression, however, the subnuclear distribution of nuclear pnn is altered, resulting in its redistribution from nuclear speckles to a diffuse nucleoplasmic form. The diffuse subnuclear distribution of nuclear pnn is not due to epitope masking, accelerated protein turnover or post-translational modification. Furthermore, we find that SR-cyp regulates the subnuclear distribution of other SR family proteins, including SC35 and SRm300, in a similar manner as it does on nuclear pnn. This result is significant because it suggests that SR-cyp plays a general role in modulating the distribution pattern of SR-like and SR proteins, similar to that of Clk (cdc2-like kinase)/STY on SR family splicing factors. SR-cyp might direct its effect via either alteration of protein folding/conformation or of protein-protein interaction and thus may add another control level of regulation of SR family proteins and modification of their functions

S-R associations, their extinction, and recovery in an animal model of anxiety: a new associative account of phobias without recall of original trauma.

Science.gov (United States)

Laborda, Mario A; Miller, Ralph R

2011-06-01

Associative accounts of the etiology of phobias have been criticized because of numerous cases of phobias in which the client does not remember a relevant traumatic event (i.e., Pavlovian conditioning trial), instructions, or vicarious experience with the phobic object. In three lick suppression experiments with rats as subjects, we modeled an associative account of such fears. Experiment 1 assessed stimulus-response (S-R) associations in first-order fear conditioning. After behaviorally complete devaluation of the unconditioned stimulus, the target stimulus still produced strong conditioned responses, suggesting that an S-R association had been formed and that this association was not significantly affected when the outcome was devalued through unsignaled presentations of the unconditioned stimulus. Experiments 2 and 3 examined extinction and recovery of S-R associations. Experiment 2 showed that extinguished S-R associations returned when testing occurred outside of the extinction context (i.e., renewal) and Experiment 3 found that a long delay between extinction and testing also produced a return of the extinguished S-R associations (i.e., spontaneous recovery). These experiments suggest that fears for which people cannot recall a cause are explicable in an associative framework, and indicate that those fears are susceptible to relapse after extinction treatment just like stimulus-outcome (S-O) associations. Copyright © 2010. Published by Elsevier Ltd.

Measurement of the internal bremsstrahlung spectrum of a 89Sr beta emitter in the 1–100 keV photon energy regime

International Nuclear Information System (INIS)

Singh, Amrit; Dhaliwal, A.S.

2015-01-01

The internal bremsstrahlung (IB) spectrum of 89 Sr, which is a unique first forbidden beta emitter, is studied in the 1–100 keV photon energy regime. The IB spectrum is experimentally measured using a Si(Li) detector, which is efficient in this photon energy regime, and is compared with the IB distributions that are predicted by the Knipp, Uhlenbeck and Bloch (KUB), Nilsson, and Lewis and Ford theories. In the soft energy regime up to 15 keV, the measured results are in agreement with all the aforementioned theories. However, from 16–30 keV, the experimental results are in agreement with the Lewis and Ford theory, which applies to forbidden transitions, and at higher photon energies, the Nilsson theory best describes the measured results. The differences among the different theories also increase with the photon energy. The effect of the electrostatic Coulomb field on the IB process for beta emitters with different end-point energies is investigated by comparing the ratio of the IB probabilities predicted using the KUB and Nilsson theories for 35 S and 89 Sr, i.e., soft and hard beta emitters, respectively. The Coulomb effect is shown to be significant in the high photon energy regime and for beta emitters with low end-point energies. - Highlights: • Internal bremsstrahlung spectrum of 89 Sr, a unique first forbidden beta emitter, is studied. • The measurements are taken in the photon energy regions of 1–100 keV with Si(Li) detector. • The measured results are deviating from Lewis and Ford theory and are close to the Nilsson theory. • The effect of Coulomb field on the IB process for different end point energy sources is investigated. • Effect of Coulomb field is more for low energy beta emitter towards the high energy end

Synthesis and luminescence properties of novel LiSrPO{sub 4}:Dy{sup 3+} phosphor

Energy Technology Data Exchange (ETDEWEB)

Sun, Jiayue, E-mail: jiayue_sun@126.com [School of Science, Beijing Technology and Business University, Beijing 100048 (China); Zhang, Xiangyan [School of Science, Beijing Technology and Business University, Beijing 100048 (China); Xia, Zhiguo, E-mail: xiazg426@yahoo.com.cn [School of Materials Sciences and Technology, China University of Geosciences, Beijing 100083 (China); Du, Haiyan [School of Science, Beijing Technology and Business University, Beijing 100048 (China)

2011-11-15

Graphical abstract: Novel LiSrPO4:Dy{sup 3+} phosphors were synthesized by solid-state reaction, and Dy{sup 3+}-doped concentration dependent luminescence properties, concentration quenching effect and the decay times were investigated in detail. Highlights: {yields} LiSrPO{sub 4}:Dy{sup 3+} could be excited by UV light and exhibited blue and yellow emission. {yields} Concentration quenching effect of LiSrPO{sub 4}:Dy{sup 3+} samples were investigated in detail. {yields} Decay times are estimated to be 0.57-0.89 ms for Dy{sup 3+} in LiSrPO{sub 4} host. -- Abstract: Novel LiSrPO{sub 4}:Dy{sup 3+} phosphors for white light-emitting diodes (w-LEDs) were synthesized by the conventional solid-state reaction. X-ray powder diffraction (XRD) analysis confirmed the phase formation of LiSrPO{sub 4}:Dy{sup 3+} materials. Luminescence properties results showed that the phosphor could be efficiently excited by the UV-vis light region from 250 to 460 nm, and it exhibited blue (483 nm) and yellow (574 nm) emission corresponding to {sup 4}F{sub 9/2} {yields} {sup 6}H{sub 15/2} transitions and {sup 4}F{sub 9/2} {yields} {sup 6}H{sub 13}/{sub 2} transitions, respectively. The luminescence intensity of LiSrPO{sub 4}:xDy{sup 3+} phosphor firstly increased and then decreased with increasing Dy{sup 3+} concentration, and reached the maximum at x = 0.03. It was found that concentration quenching occurred as a result of dipole-dipole interaction according to the Dexter's theory. The decay time was also determined for various concentrations of Dy{sup 3+} in LiSrPO{sub 4}.

89Sr and 90Sr in atmospheric precipitations in May 1986 in Bucharest-Magurele area

International Nuclear Information System (INIS)

Paunescu, N.; Vata, I.

1987-08-01

Sr-89 and Sr-90 were determined in the fallout of May 1986. The maximum values of 335 Bq/(m 2 * 6 hours) and 110 Bq/(m 2 * 6 hours) were observed at May 2 and 5. Throughout May 1986 a quantity of 860 Bq/m 2 of Sr-90 deposited from the fallout in the Bucharest -Magurele area was determined. (authors)

License renewal

International Nuclear Information System (INIS)

Newberry, S.

1993-01-01

This article gives an overview of the process of license renewal for nuclear power plants. It explains what is meant by license renewal, the significance of license renewal, and goes over key elements involved in the process of license renewal. Those key elements are NRC requirements embodied in 10 CFR Part 54 (Reactor Safety) and 10 CFR Part 51 (Environmental Issues). In addition Industry Reports must be developed and reviewed. License renewal is essentially the process of applying for a 20 year extension to the original 40 year operating license granted for the plant. This is a very long term process, which involves a lot of preparation, and compliance with regulatory rules and guidelines. In general it is a process which is expected to begin when plants reach an operating lifetime of 20 years. It has provisions for allowing the public to become involved in the review process

Half-metallic behavior and electronic structure of Sr2CrMoO6 magnetic system

International Nuclear Information System (INIS)

Bonilla, C.M.; Landinez Tellez, D.A.; Arbey Rodriguez, J.; Vera Lopez, E.; Roa-Rojas, J.

2007-01-01

Complex perovskite materials with the A 2 BB'O 6 formula have been recently studied because of their peculiar magnetic and electronic properties. The origin of magnetism in the double perovskite Sr 2 FeMoO 6 brought these properties again into discussion. Recently, a new interaction mechanism was proposed for cases in which the hybridization of 3d and 2p levels of Mo with the 3d Fe levels is responsible for the half-metallic behavior in the Sr 2 FeMoO 6 material. We report on LAPW ab initio calculations within the generalized gradient approximation (GGA) to density functional theory (DFT) for another double perovskite, namely, Sr 2 CrMoO 6 . Our results show that this is also a half-metallic system. We correlate our results with an extension of the recent model proposed by Sarma to explain the conduction mechanism in this compound

A model based on Copula Theory for sustainable and social responsible investments

Directory of Open Access Journals (Sweden)

Amelia Bilbao-Terol

2016-01-01

Full Text Available In this paper, a model is proposed that allows us to obtain a portfolio made up of sustainable and socially responsible (SR investment funds. This portfolio tracks the one that investors might have chosen if they had not taken into account social, ethical and ecological (SEE issues in their investment decisions. Therefore, in the first stage, reference portfolio exclusively made up of conventional funds is obtained. For the construction of the conventional portfolio the Prospect Theory has been used: net profits as the financial objective and error function as the utility function. In the second stage, a portfolio consisting exclusively of SR-funds is built. To do so, the reference portfolio is used as an ideal point, with the objectives of the SR-investor being the relative wealth with respect to the reference portfolio and the SEE quality of the portfolio. The relative wealth will be manipulated by a downside-risk measure, the Conditional Value at Risk (CVaR, and the periodic values of the portfolio. The second objective is the SR Quality of the portfolio, taking into account the personal values of a particular investor. This is built using Fuzzy Set Theory tools. We are faced with a multi-objective problem which is solved by using Goal Programming methodology. The estimation of both conventional and SR markets has been carried out by a semi-parametric approach by using the Copula Theory for modeling the dependence structure of the assets’ returns. The approach has been applied to a set of 38 conventional and 12 ethical funds domiciled in Spain.

87Sr/86Sr ratios in hydrothermal waters and deposits from the east pacific rise at 210N

International Nuclear Information System (INIS)

Albarede, F.; Michard, A.; Minster, J.F.; Michard, G.

1981-01-01

87 Sr/ 86 Sr ratios of three hydrothermal waters collected on the East Pacific Rise at 21 0 N define a mixing line between seawater and a hydrothermal end-member at 0.7030 which is derived by seawater-basalt interaction at ca. 350 0 C and water/rock ratio of about 1.5. Sr concentrations are not affected in the process while Mg uptake from seawater is almost complete. Up to 2/3 of this hydrothermal component is involved in anhydrite precipitation while the Sr isotopic ratio in sulfides (chalcopyrite + sphalerite) cannot be distinguished from that of sulfate. It is estimated that ca. 1 x 10 10 moles of strontium are yearly cycled in the hydrothermal systems of mid-oceanic ridges, thereby affecting the 87 Sr/ 86 Sr budget of seawater. Mass balance between river runoff, limestone precipitation and ridge basalt alteration suggests that the 87 Sr/ 86 Sr ratios of the river runoff are in the range 0.7097-0.7113, and are largely dominated by limestone alteration. (orig.)

Synthetic clay excels in 90Sr removal

International Nuclear Information System (INIS)

Komarneni, Sridhar; Kodama, Tatsuya; Paulus, William J.; Carlson, C.

2000-01-01

Tests with actual ground water from Hanford site, and fundamental studies of 2Na + →Sr 2+ exchange equilibria revealed that a synthetic clay is extremely selective for 90 Sr with a high capacity for uptake. Comparative studies with existing Sr selective ion exchangers clearly revealed that the present synthetic clay exhibited the best performance for 90 Sr removal from actual ground water collected from three different locations at Hanford. This novel Sr ion sieve is expected to be useful for the decontamination of the environment after accidental release and contamination with 90 Sr. (c) 2000 Materials Research Society

The influence of Sr on the microstructure, degradation and stress corrosion cracking of the Mg alloys - ZK40xSr.

Science.gov (United States)

Chen, Lianxi; Bin, Yuanhong; Zou, Wenqi; Wang, Xiaojian; Li, Wei

2017-02-01

In the present work, new magnesium (Mg) alloys (Mg-4Zn-0.6Zr-xSr, x=0, 0.4, 0.8, 1.2, 1.6wt%; ZK40xSr) were prepared and studied as potential biodegradable materials. The influence of strontium (Sr) addition on the properties of the new Mg alloys was investigated, which included microstructure, corrosion degradation, and the stress corrosion cracking (SCC) susceptibility. The average grain size of the ZK40Sr was approximately 100µm, which was significantly smaller than that of ZK40 alloy without Sr (402.3±40.2µm). The size of grain boundaries precipitates in the ZK40xSr alloys gradually increased with the increase of Sr content. The grain boundaries finally showed a continuously distribution and net-like shape. The degradation test showed that the average degradation rate of the ZK40xSr alloys increased with the increase of Sr addition. In the case of Mg-4Zn-0.6Zr, the degradation rate was 2.2mgcm -2 day -1 , which was lower than that of Mg-4Zn-0.6Zr-1.6Sr (4.93mgcm -2 day -1 ). When the ZK40xSr alloys were immersed in m-SBF, the rod-like Sr-contained hydroxyapatite (HA) substance was detected, which was known to enhance cell growth around bone implants. The fracture surfaces of the as-cast Mg-4Zn-0.6Zr-1.6Sr were shown intergranular stress corrosion cracking (IGSCC) patterns. The increase of SCC susceptibility of the higher Sr ZK40xSr alloys was attributed to the increase of micro-galvanic corrosion between the α-Mg and the grain boundaries precipitates. The SCC susceptibility values were ≈0.13 and ≈0.41 for the Mg-4Zn-0.6Zr-0.4Sr and the Mg-4Zn-0.6Zr-1.6Sr, respectively. Copyright © 2016 Elsevier Ltd. All rights reserved.

Renewable energy

International Nuclear Information System (INIS)

Yoon, Cheon Seok

2009-09-01

This book tells of renewable energy giving description of environment problem, market of renewable energy and vision and economics of renewable energy. It also deals with solar light like solar cell, materials performance, system and merit of solar cell, solar thermal power such as solar cooker and solar collector, wind energy, geothermal energy, ocean energy like tidal power and ocean thermal energy conversion, fuel cell and biomass.

Evaluating investments in renewable energy under policy risks

International Nuclear Information System (INIS)

Gatzert, Nadine; Vogl, Nikolai

2016-01-01

The considerable amount of required infrastructure and renewable energy investments expected in the forthcoming years also implies an increasingly relevant contribution of private and institutional investors. In this context, especially regulatory and policy risks have been shown to play a major role for investors when evaluating investments in renewable energy and should thus also be taken into account in risk assessment and when deriving risk-return profiles. In this paper, we provide a stochastic model framework to quantify policy risks associated with renewable energy investments (e.g. a retrospective reduction of a feed-in tariff), thereby also taking into account energy price risk, resource risk, and inflation risk. The model is illustrated by means of simulations and scenario analyses, and it makes use of expert estimates and fuzzy set theory for quantifying policy risks. Our numerical results for a portfolio of onshore wind farms in Germany and France show that policy risk can strongly impact risk-return profiles, and that cross-country diversification effects can considerably decrease the overall risk for investors. - Highlights: •Quantification of policy risks associated with renewable energy investments. •Results emphasize that policy risk has a major impact on risk and return. •Study of the cross-country diversification potential. •Cross-country diversification can considerably decrease the risk for an investor.

The Renewable Energy Data Explorer: Mapping Our Renewable Energy Future

Energy Technology Data Exchange (ETDEWEB)

2017-04-13

The Renewable Energy (RE) Data Explorer, developed by the National Renewable Energy Laboratory, is an innovative web-based platform that allows users to visualize and analyze renewable energy potential. The RE Data Explorer informs prospecting, integrated planning, and policymaking to enable low emission development.

Construction of the seawater 87Sr/86Sr curve for the Cenozoic and Cretaceous: supporting data

International Nuclear Information System (INIS)

Koepnick, R.B.; Burke, W.H.; Denison, R.E.; Hetherington, E.A.; Nelson, H.F.; Otto, J.B.; Waite, L.E.

1985-01-01

We present the data used to construct the Cenozoic and Cretaceous portion of the Phanerozoic curve of seawater 87 Sr/ 86 Sr that had been given in summary form by W.H. Burke and coworkers. All Cenozoic samples (128) and 22 Cretaceous samples are foram-nannofossil oozes and limestones from DSDP cores distributed among 13 sites in the Atlantic, Pacific and Indian Oceans, and the Caribbean Sea. Non-DSDP Cretaceous samples (126) include limestone, anhydrite and phosphate samples from North America, Europe and Asia. Determination of the 87 Sr/ 86 Sr value of seawater at particular times in the past is based on comparison of ratios derived from coeval marine samples from widely separated geographic areas. The general configuration of the Cenozoic and Cretaceous curve appears to be strongly influenced by the history of plate interactions and sea-floor spreading. Specific rises and falls in the 87 Sr/ 86 Sr of seawater, however, may be caused by a variety of factors such as variation in lithologic composition of the crust exposed to weathering, configuration and topographic relief of continents, volcanic activity, rate of sea-floor spreading, extent of continental inundation by epeiric seas, and variations in both climate and paleo-oceanographic conditions. Many or all of these factors are probably related to global tectonic processes, yet their combined effect on the temporal variation of seawater 87 Sr/ 86 Sr can complicate a direct plate-tectonic interpretation for portions of the seawater curve. (Auth.)

High charge carrier density at the NaTaO3/SrTiO3 hetero-interface

KAUST Repository

Nazir, Safdar; Schwingenschlö gl, Udo

2011-01-01

The formation of a (quasi) two-dimensional electron gas between the band insulators NaTaO3 and SrTiO3 is studied by means of the full-potential linearized augmented plane-wave method of density functional theory. Optimization of the atomic positions

Enthalpies of formation of Cd0.917Sr0.083, Cd0.857Sr0.143 and Cd0.667Sr0.333 intermetallic compounds

International Nuclear Information System (INIS)

Agarwal, Renu; Singh, Ziley

2008-01-01

Cadmium is expected to be the solvent for pyrochemical processing of the metallic nuclear fuel. Therefore, thermodynamic properties of cadmium with various fuel and clad elements are of interest. Enthalpies of formation of the intermetallic compounds of Cd-Sr system, Cd 0.917 Sr 0.083 , Cd 0.857 Sr 0.143 and Cd 0.667 Sr 0.333 were determined by precipitation using Calvet calorimeter. Enthalpies of formation of the compounds were found to be -3.05 ± 0.5 kJ mol -1 at 723 K, -14.2 ± 0.7 kJ mol -1 at 843 K and -28.4 ± 0.8 kJ mol -1 at 863 K, respectively. Enthalpies of formation of Cd 0.917 Sr 0.083 and Cd 0.857 Sr 0.143 were also determined by partial enthalpy of formation measurements and the values were found to be -3.9 ± 1.1 kJ mol -1 at 723 K and -13.42 ± 1.2 kJ mol -1 at 843 K, respectively. Miedema model was used to estimate the enthalpies of formation of these compounds and the estimated values were compared with the experimentally determined values

Thermodynamic Modeling of Sr/TRU Removal

International Nuclear Information System (INIS)

Felmy, A.R.

2000-01-01

This report summarizes the development and application of a thermodynamic modeling capability designed to treat the Envelope C wastes containing organic complexants. A complete description of the model development is presented. In addition, the model was utilized to help gain insight into the chemical processes responsible for the observed levels of Sr, TRU, Fe, and Cr removal from the diluted feed from tank 241-AN-107 which had been treated with Sr and permanganate. Modeling results are presented for Sr, Nd(III)/Eu(III), Fe, Cr, Mn, and the major electrolyte components of the waste (i.e. NO 3 , NO 2 , F,...). On an overall basis the added Sr is predicted to precipitate as SrCO 3 (c) and the MnO 4 - reduced by the NO 2 - and precipitated as a Mn oxide. These effects result in only minor changes to the bulk electrolyte chemistry, specifically, decreases in NO 2 - and CO 3 2- , and increases in NO 3 - and OH - . All of these predictions are in agreement with the experimental observations. The modeling also indicates that the majority of the Sr, TRU's (or Nd(III)/Eu(III)) analogs, and Fe are tied up with the organic complexants. The Sr and permanganate additions are not predicted to effect these chelate complexes significantly owing to the precipitation of insoluble Mn oxides or SrCO 3 . These insoluble phases maintain low dissolved concentrations of Mn and Sr which do not affect any of the other components tied up with the complexants. It appears that the removal of the Fe and TRU'S during the treatment process is most likely as a result of adsorption or occlusion on/into the Mn oxides or SrCO 3 , not as direct displacement from the complexants into precipitates. Recommendations are made for further studies that are needed to help resolve these issues

Accounting for the income of non-renewable resources - Four essays on new theoretical approaches

Energy Technology Data Exchange (ETDEWEB)

Wei, Taoyuan

2009-01-15

Non-renewable resources are widely extracted and used in today's global economy. On the one hand, the use of these resources generates huge cash flows that can be used for current consumption. On the other hand, the extraction of these resources implies less wealth of these natural resources in the future. To compensate for this wealth decrease, we have to accumulate other kinds of real wealth, like man-made capital, human capital, and renewable resources. The wealth accumulation can be achieved by activities of investments. Reasonable financial support for the investments should come from cash flows related to non-renewable resources. Hence, cash flows related to non-renewable resources should be divided for two basic purposes: current consumption and savings to support activities of investments. The trade-off between current consumption and savings invokes a fundamental question: how much of the cash flows can we use for current consumption without impoverishing the future? Following the literature line from Hicks (1946, Chapter 14) via Samuelson (1961) to Sefton and Weale (2006), in the first essay of this dissertation, Geir Asheim and I develop a theory of sectoral income. The theory can be applied to estimate income at a sectoral level. By this notion of sectoral income, we can answer the fundamental question concerning the division of the cash flows generated by non-renewable resources into consumption and savings. In particular, by applying the new theory in this dissertation, I provide a new method for estimating real income generated by non-renewable resources. The new method has at least two advantages when compared with the wealth-based method, which is a commonly applied method in practical resource accounting. By the wealth-based method, sectoral income is associated with the interest on the sector's wealth, where the wealth is estimated as the present value of cash flows generated from the sector (see, e.g., Aslaksen et al., 1990, and Brekke

Using 87Sr/86Sr ratios to investigate changes in stream chemistry during snowmelt in the Provo River, Utah, USA

Science.gov (United States)

Hale, C. A.; Carling, G. T.; Fernandez, D. P.; Nelson, S.; Aanderud, Z.; Tingey, D. G.; Dastrup, D.

2017-12-01

Water chemistry in mountain streams is variable during spring snowmelt as shallow groundwater flow paths are activated in the watershed, introducing solutes derived from soil water. Sr isotopes and other tracers can be used to differentiate waters that have interacted with soils and dust (shallow groundwater) and bedrock (deep groundwater). To investigate processes controlling water chemistry during snowmelt, we analyzed 87Sr/86Sr ratios, Sr and other trace element concentrations in bulk snowpack, dust, soil, soil water, ephemeral channels, and river water during snowmelt runoff in the upper Provo River watershed in northern Utah, USA, over four years (2014-2017). Strontium concentrations in the river averaged 20 ppb during base flow and decreased to 10 ppb during snowmelt runoff. 87Sr/86Sr ratios were around 0.717 during base flow and decreased to 0.715 in 2014 and 0.713 in 2015 and 2016 during snowmelt, trending towards less radiogenic values of mineral dust inputs in the Uinta Mountain soils. Ephemeral channels, representing shallow flow paths with soil water inputs, had Sr concentrations between 7-20 ppb and 87Sr/86Sr ratios between 0.713-0.716. Snowpack Sr concentrations were generally soils that contain accumulated dust deposits with a less radiogenic 87Sr/86Sr ratio. These results suggest that flow paths and atmospheric dust are important to consider when investigating variable solute loads in mountain streams.

Preparation and crystal structure of SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/

Energy Technology Data Exchange (ETDEWEB)

Cordier, G; Eisenmann, B; Schaefer, H [Technische Hochschule Darmstadt (Germany, F.R.). Fachbereich Anorganische Chemie und Kernchemie

1976-10-01

SrCu/sub 2/Sb/sub 2/ and SrZnBi/sub 2/ have been prepared and analytically and structurally characterized. SrCu/sub 2/Sb/sub 2/ crystallizes tetragonal in the CaBe/sub 2/Ge/sub 2/ structure type. SrZnBi/sub 2/ has its own structure type. In both structures the transition metal atoms form with the semimetal atoms tetragonal pyramids, which are connected by common edges of the basis to twodimensional sheets. These sheets are separated in the case of SrCu/sub 2/Sb/sub 2/ by single sheets of strontium atoms, in the case of SrZnBi/sub 2/ by double sheets of strontium atoms in which fourfold nets of Bi atoms are located.

Spectroscopic and electric dipole properties of Sr+Ar and SrAr systems including high excited states

Science.gov (United States)

Hamdi, Rafika; Abdessalem, Kawther; Dardouri, Riadh; Al-Ghamdi, Attieh A.; Oujia, Brahim; Gadéa, Florent Xavier

2018-01-01

The spectroscopic properties of the fundamental and several excited states of Sr+Ar and SrAr, Van der Waals systems are investigated by employing an ab initio method in a pseudo-potential approach. The potential energy curves and the spectroscopic parameters are displayed for the 1-10 2Σ+, 1-6 2Π and 1-3 2Δ electronic states of the Sr+Ar molecule and for the 1-6 1Σ+, 1-4 3Σ+, 1-3 1,3Π and 1-3 1,3Δ states of the neutral molecule SrAr. In addition, from these curves, the vibrational levels and their energy spacing are deduced for Σ+, Π and Δ symmetries. The spectra of the permanent and transition dipole moments are studied for the 1,3Σ+ states of SrAr, which are considered to be two-electron systems and 2Σ+ states of the single electron Sr+Ar ion. The spectroscopic parameters obtained for each molecular system are compared with previous theoretical and experimental works. A significant correlation revealed the accuracy of our results.

Sr - an element shows the way - Applications of Sr isotopes for provenance, tracing and migration (Invited)

Science.gov (United States)

Prohaska, T.; Irrgeher, J.; Zitek, A.; Teschler Nicola, M.

2010-12-01

Strontium - named after the small Scottish town Strontian - as such is an element with little popularity. Firstly described by Martin Heinrich Klaproth in 1798, the metal is used in metallurgy to some extent whereas its compounds are interesting in glass industries, electronics and pyrotechnics. The element has chemical similarity to Ca and makes up 1/60 of the earth’s amount of the latter. Nonetheless, it is its isotopic composition which makes Sr so interesting for a large number of scientists. The natural composition of the four naturally occurring isotopes (84Sr, 86Sr 87Sr and 88Sr) varies in nature due to the radioactive decay of 87Rb to 87Sr. Thus, it was early recognized as geochronometer especially in Ca rich matrices. With increasing precision of applied methodology, the natural variation of the 87Sr/86Sr isotope ratio (analyzed at first mainly by thermal ionization mass spectrometry (TIMS)) became more and more popular in provenance studies. The natural variation of the ratio is mainly determined by the geological age and the original composition of the rock and can be used therefore as fingerprint of the local geology. The ratio is transferred with no significant fractionation via the water into plants and finally via the food chain into animal and human tissues (especially bones and teeth). As the element is chemically similar to Ca, it appears in most matrices. The use for provenance studies is supported by the fact that the long half life (4.8 x 1010 years) does not lead to an alteration during the time scales which are investigated (from recent samples to human or animal skeletal remains which date back up to 30.000 BC). The uniqueness of the system besides the natural variation is defined by the ubiquity in nature and the relatively high (and thus measurable) elemental concentration in most tissues. It was finally the advent of multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) which augmented the number of applications

Epitaxial growth and thermodynamic stability of SrIrO3/SrTiO3 heterostructures

Science.gov (United States)

Groenendijk, D. J.; Manca, N.; Mattoni, G.; Kootstra, L.; Gariglio, S.; Huang, Y.; van Heumen, E.; Caviglia, A. D.

2016-07-01

Obtaining high-quality thin films of 5d transition metal oxides is essential to explore the exotic semimetallic and topological phases predicted to arise from the combination of strong electron correlations and spin-orbit coupling. Here, we show that the transport properties of SrIrO3 thin films, grown by pulsed laser deposition, can be optimized by considering the effect of laser-induced modification of the SrIrO3 target surface. We further demonstrate that bare SrIrO3 thin films are subject to degradation in air and are highly sensitive to lithographic processing. A crystalline SrTiO3 cap layer deposited in-situ is effective in preserving the film quality, allowing us to measure metallic transport behavior in films with thicknesses down to 4 unit cells. In addition, the SrTiO3 encapsulation enables the fabrication of devices such as Hall bars without altering the film properties, allowing precise (magneto)transport measurements on micro- and nanoscale devices.

Renewable Electricity Futures Study. Volume 2: Renewable Electricity Generation and Storage Technologies

Energy Technology Data Exchange (ETDEWEB)

Augustine, C.; Bain, R.; Chapman, J.; Denholm, P.; Drury, E.; Hall, D.G.; Lantz, E.; Margolis, R.; Thresher, R.; Sandor, D.; Bishop, N.A.; Brown, S.R.; Cada, G.F.; Felker, F.

2012-06-01

The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%-90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT).

87Sr/86Sr ratios in permo-carboniferous sea water from the analyses of well-preserved brachiopod shells

International Nuclear Information System (INIS)

Popp, B.N.; Anderson, T.F.

1986-01-01

Sr isotopic analyses of well-preserved portions of Permo-Carboniferous brachiopods distributed globally confirm the general shape of the Sr isotope age curve established by previous workers for this time interval. There is little variation between the SR isotopic composition of unaltered portions of brachiopods and that of portions of the same shell interpreted to be diagenetically altered (based on cathodoluminescence, elemental, and stable isotopic data). However, the Sr isotopic composition in diagenetically altered micritic matrix adjacent to the shell is more radiogenic. The Sr isotopic composition in the unaltered portions of calcitic megafossils has potential as a stratigraphic tool. (author)

Renewable energy.

Science.gov (United States)

Destouni, Georgia; Frank, Harry

2010-01-01

The Energy Committee of the Royal Swedish Academy of Sciences has in a series of projects gathered information and knowledge on renewable energy from various sources, both within and outside the academic world. In this article, we synthesize and summarize some of the main points on renewable energy from the various Energy Committee projects and the Committee's Energy 2050 symposium, regarding energy from water and wind, bioenergy, and solar energy. We further summarize the Energy Committee's scenario estimates of future renewable energy contributions to the global energy system, and other presentations given at the Energy 2050 symposium. In general, international coordination and investment in energy research and development is crucial to enable future reliance on renewable energy sources with minimal fossil fuel use.

Review of SR 97 performance assessment

International Nuclear Information System (INIS)

Glynn, P.D.

2000-01-01

This review has identified many technical problems in the SR 97 performance assessment. The general impression of this reviewer is that SKB has been disingenuous in its performance assessment effort. It has not cited important differences of opinion with its own views. Furthermore, there are many inconsistencies in the SR 97 report that all together leave the impression that there are many more uncertainties in the SR 97 performance assessment than SKB would perhaps care to admit. Additionally, despite SKB's statements to the contrary, many of the analyses conducted for the SR 97 performance assessment can be clearly shown not to have been based on 'conservative' assumptions. Finally, SKB has made little effort to consider possible coupling effects between their different scenarios in SR 97. This is a serious flaw in the SR 97 performance assessment. The comments in this review should not be taken to imply that the KBS-3 nuclear waste disposal method will not be able to meet the safety and radiation protection requirements which SKI and SSI have specified in recent years. Instead, my conclusion is simply that the SR 97 performance assessment of the KBS-3 method would have been more believable had it been based on a forthright and comprehensive discussion of facts, uncertainties and opinions, and on a more conservative choice of assumptions. As it stands, the SR 97 performance assessment is not very credible

87Sr/86Sr isotopes in grapes of different cultivars: A geochemical tool for geographic traceability of agriculture products.

Science.gov (United States)

Tescione, Ines; Marchionni, Sara; Casalini, Martina; Vignozzi, Nadia; Mattei, Massimo; Conticelli, Sandro

2018-08-30

87 Sr/ 86 Sr was determined on fresh red and white grapes, soils and rocks from three selected vineyards to verify the isotopic relationships between the fruit of the vine and geologic substrata of vineyards. 87 Sr/ 86 Sr were determined on sampled grapes of four different harvest years and different grape varieties, on bioavailable fraction of soils, on whole soils, and on bedrocks from the geo-pedological substratum of the vineyards. The vineyards chosen for the experimental works belong to an organic farming winery and thus cultivation procedures were strictly controlled. Grapes were sampled during the harvests of four different but consecutive years with 87 Sr/ 86 Sr that does not change reflecting the values of the soil bioavailable fraction. No variations among grapes from different vine cultivars were observed. A strict isotope relationship with soil bio-available fraction was observed. These findings demonstrate the reliability of 87 Sr/ 86 Sr, even at a very small scale, for food products geographic origin assessment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Fusion fuel and renewables

International Nuclear Information System (INIS)

Entler, Slavomir

2015-01-01

It is shown that fusion fuel meets all aspects applied when defining renewables. A table of definitions of renewables is presented. The sections of the paper are as follows: An industrial renewable source; Nuclear fusion; Current situation in research; Definitions of renewable sources; Energy concept of nuclear fusion; Fusion fuel; Natural energy flow; Environmental impacts; Fusion fuel assessment; Sustainable power; and Energy mix from renewables. (P.A.)

Development of 87Sr/86Sr maps as targeted strategy to support wine quality.

Science.gov (United States)

Durante, Caterina; Bertacchini, Lucia; Cocchi, Marina; Manzini, Daniela; Marchetti, Andrea; Rossi, Maria Cecilia; Sighinolfi, Simona; Tassi, Lorenzo

2018-07-30

This study summarizes the results obtained from a systematic and long-term project aimed at the development of tools to assess the provenance of food in the oenological sector. In particular, 87 Sr/ 86 Sr isotope ratios were measured on statistically representative set of soils, vine branches and wines sampled in the production district of Modena, worldwide known for the Lambrusco wines production. The obtained data were used to build strontium isotopic maps able to objectively support the Lambrusco PDO wines origin as well as other products of the Modena district. Finally, a strong relationship was found between the 87 Sr/ 86 Sr isotope ratios of soils and vine branches on a large scale, highlighting and confirming once more the idea that plants can also represent an optimal sampling device to support geographical traceability. Copyright © 2018 Elsevier Ltd. All rights reserved.

A surface-renewal model of cross-flow microfiltration

Directory of Open Access Journals (Sweden)

A. Hasan

2013-03-01

Full Text Available A mathematical model using classical cake-filtration theory and the surface-renewal concept is formulated for describing cross-flow microfiltration under dynamic and steady-state conditions. The model can predict the permeate flux and cake buildup in the filter. The three basic parameters of the model are the membrane resistance, specific cake resistance and rate of surface renewal. The model is able to correlate experimental permeate flow rate data in the microfiltration of fermentation broths in laboratory- and pilot-scale units with an average root-mean-square (RMS error of 4.6%. The experimental data are also compared against the critical-flux model of cross-flow microfiltration, which has average RMS errors of 6.3, 5.5 and 6.1% for the cases of cake filtration, intermediate blocking and complete blocking mechanisms, respectively.

Trends in (LaMnO3)n/(SrTiO3)m superlattices with varying layer thicknesses

KAUST Repository

Jilili, J.; Cossu, Fabrizio; Schwingenschlö gl, Udo

2015-01-01

We investigate the thickness dependence of the structural, electronic, and magnetic properties of (LaMnO3)n/(SrTiO3)m (n, m = 2, 4, 6, 8) superlattices using density functional theory. The electronic structure turns out to be highly sensitive

Renewable Electricity Futures Study. Volume 2. Renewable Electricity Generation and Storage Technologies

Energy Technology Data Exchange (ETDEWEB)

Augustine, Chad [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bain, Richard [National Renewable Energy Lab. (NREL), Golden, CO (United States); Chapman, Jamie [Texas Tech Univ., Lubbock, TX (United States); Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Drury, Easan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hall, Douglas G. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lantz, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States); Margolis, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Thresher, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sandor, Debra [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bishop, Norman A. [Knight Piesold, Denver, CO (United States); Brown, Stephen R. [HDR/DTA, Portland, ME (Untied States); Cada, Glenn F. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Felker, Fort [National Renewable Energy Lab. (NREL), Golden, CO (United States); Fernandez, Steven J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Goodrich, Alan C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hagerman, George [Virginia Polytechnic Inst. and State Univ. (Virginia Tech), Blacksburg, VA (United States); Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Neil, Sean [Ocean Renewable Energy Coalition, Portland, OR (United States); Paquette, Joshua [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Tegen, Suzanne [National Renewable Energy Lab. (NREL), Golden, CO (United States); Young, Katherine [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2012-06-15

The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%–90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT). Learn more at the RE Futures website. http://www.nrel.gov/analysis/re_futures/

Review of SR 97

International Nuclear Information System (INIS)

Voss, C.I.

2000-01-01

The safety analysis conducted by SKB for SR 97 is impressive in terms of both scale and content. In addition to an eventual solution to Sweden's nuclear waste isolation question, much general scientific knowledge of real value in other applications will be created as a by-product of SKB's efforts. This review focuses on those geoscience aspects of SR 97 that have the most important effects on radionuclide release from each barrier. Indeed, SR 97 elucidates the most important geoscience parameters that control releases from the near field and the far field; these comprise mainly the transport resistance parameter, and the sorption coefficients for each nuclide, the matrix diffusion coefficient, and the Darcy flux. The Main Report is the most important document in SR 97 inasmuch as it is the only one that brings together all of the supporting work to answer the question of safety. Unfortunately pervading the good supporting work done is the impression that the Main Report is not balanced, that it emphasizes optimistic aspects and downplays the negative. SKB specifies 3 main requirements to guarantee proper repository function: a non-oxidizing subsurface environment, temperatures less than 100 C, and a mechanically stable low-permeability buffer surrounding the canisters. The first and third requirements are not thoroughly proven by SKB. One source of near-field doubt stems from the consequences of combinations of scenarios in which several negative events are linked, while the effect of each scenario is mainly evaluated only independently in SR 97. More pertinently, disastrous breakdown of complex systems may occur due to a chain of linked failures. For example, in the glacial scenario: high ground-water flow (possible ablation of buffer and high fluid transport), change in ground-water chemistry (even the possibility of oxidizing conditions), new flow paths, significant changes in mechanical stress and possible motion along faults (which may also generate new flow

Experimental and theoretical investigation of electronic structure of SrFeO3-xFx epitaxial thin films prepared via topotactic reaction

Science.gov (United States)

Katayama, Tsukasa; Chikamatsu, Akira; Kamisaka, Hideyuki; Kumigashira, Hiroshi; Hasegawa, Tetsuya

2016-02-01

We investigated the electronic structure of perovskite SrFeO3-xFx (0.6 ≤ x ≤ 1) films by optical absorption, photoemission, and X-ray absorption spectroscopies, as well as density functional theory (DFT)-based calculations. The optical bandgap expanded with x, yielding a wider direct bandgap for the SrFeO2F film than for the LaFeO3 film. The DFT calculations suggested that the majority of FeO4F2 octahedra in the SrFeO2F film had cis configurations and that the enlarged bandgap mainly originated from bond bending in the O-Fe-O chains. We experimentally observed the valence and conduction bands of the SrFeO2F film, and found them to be qualitatively consistent with the results of DFT-based calculations.

Renewable target in sight

International Nuclear Information System (INIS)

Anon

2000-01-01

Australia's renewable energy industry is expecting several billion dollars of investment over the next 10 years following passage in December last year of the Renewable Energy Electricity) Act 2000 through Federal Parliament. The Act requires an additional 9500GWh of Australia's electricity production to be sourced from renewables by the year 2010. It also establishes a market for the 'green' component of the energy separate from the electricity itself, through a Renewable Energy Certificate (REC), whereby an accredited generator of renewable energy is able to issue one REC for each megawatt-hour of renewable energy generated

Renewable energy annual 1996

International Nuclear Information System (INIS)

1997-03-01

This report presents summary data on renewable energy consumption, the status of each of the primary renewable technologies, a profile of each of the associated industries, an analysis of topical issues related to renewable energy, and information on renewable energy projects worldwide. It is the second in a series of annual reports on renewable energy. The renewable energy resources included in the report are biomass (wood and ethanol); municipal solid waste, including waste-to-energy and landfill gas; geothermal; wind; and solar energy, including solar thermal and photovoltaic. The report also includes various appendices and a glossary

Renewable energy annual 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-03-01

This report presents summary data on renewable energy consumption, the status of each of the primary renewable technologies, a profile of each of the associated industries, an analysis of topical issues related to renewable energy, and information on renewable energy projects worldwide. It is the second in a series of annual reports on renewable energy. The renewable energy resources included in the report are biomass (wood and ethanol); municipal solid waste, including waste-to-energy and landfill gas; geothermal; wind; and solar energy, including solar thermal and photovoltaic. The report also includes various appendices and a glossary.

Preparation of Sr adsorptive fiber by impregnating with crown ether derivative for 90Sr measurement

International Nuclear Information System (INIS)

Horita, Takuma; Asai, Shiho; Hanzawa, Yukiko; Kitatsuji, Yoshihiro; Konda, Miki; Saito, Kyoichi; Fujiwara, Kunio; Sugo, Takanobu

2017-01-01

A Sr adsorption fiber was prepared for rapid analysis of 90 Sr content in the fiber using radiation-induced emulsion graft polymerization and subsequent chemical modification. A polyethylene fiber with a diameter of 13 μm was first immersed in a methanol solution of an epoxy-group-containing vinyl monomer, glycidyl methacrylate (GMA), and polyoxyethylene sorbitol ester (Tween20) as a surfactant for the graft-polymerization of GMA. Octadecylamine was then bound to a polymer chain extending from the fiber surface, providing hydrophobicity to the polymer chain. Dicyclohexano-18-crown-6 (DCH18C6) was finally impregnated onto the polymer chain via a hydrophobic interaction between the octadecyl moiety of the polymer chain and the cyclohexyl moiety of DCH18C6. The fiber surface structure, characterized by DCH18C6 molecules loosely entangled with polymer chains, allowed for the rapid adsorption of Sr ions at an adsorption rate of approximately 100-times higher than that of a commercially available Sr-selective resin (Sr Resin ® ). (author)

Preparation of 90Sr-90Y generator

International Nuclear Information System (INIS)

Jin Xiaohai; Yu Haibin; Zhang Jinming; Zhang Peixin; Lin Qiongfang

1990-01-01

In recent years, 90 Y has been considered as one of the best radionuclides for tumor radioimmunotherapy when chelated to tumor-associated antibodies. This evaluation is based on the superior properties of this radionuclide (suitable half-life, pure β-ray emitter of intermediate energy, stable daughters, and suitable chemical properties) and because it is available as a radionuclide generator product by decay of its 28a parent 90 Sr. The experimental conditions of 90 Sr- 90 Y generator are described. The elution efficiency of 90 Sr- 90 Y generator reaches 98%. One of the most important problems is the 90 Sr contamination breakthrough from the generator. The level of 90 Sr contamination must be controlled to the clinical standard. The cation exchange resin 732 (100-150 mesh) was successfully used for the separation of 90 Y from 90 Sr. The method used by the authors provides a 90 Y-HAc solution which is very simple and safe for administration to the patients. 90 Y was separated from 90 Sr almost completely, the level of the 90 Sr contamination per 740 MBq 90 Y product was only 0.74 kBq. However the toxicity of 90 Sr is extremely high, the human life-time permissible dose is 74 kBq, then 740 MBq of 90 Y is allowed to be administrated to a patient for 50-100 times

Optical spectroscopy of Ho{sup 3+}-doped SrWO{sub 4} scheelite crystal

Energy Technology Data Exchange (ETDEWEB)

Li Jianfu; Jia Guohua; Zhu Zhaojie; You Zhenyu; Wang Yan; Wu Baichang; Tu Chaoyang [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, State Key Laboratory of Structural Chemistry and National Engineering Research Center for Optoelectronic Crystalline Materials, Fuzhou, Fujian 350002 (China)

2007-04-07

Ho{sup 3+}-doped SrWO{sub 4} crystal was grown by the Czochralski method. The polarized absorption and emission spectra together with the fluorescent decay curve were measured at room temperature. The intensity parameters, radiative lifetimes and branching ratios were calculated based on the Judd-Ofelt theory. The stimulated emission cross-sections of the potential laser transitions were determined using the reciprocity method.

Renewable energy resources

CERN Document Server

Twidell, John

2015-01-01

Renewable Energy Resources is a numerate and quantitative text covering the full range of renewable energy technologies and their implementation worldwide. Energy supplies from renewables (such as from biofuels, solar heat, photovoltaics, wind, hydro, wave, tidal, geothermal, and ocean-thermal) are essential components of every nation's energy strategy, not least because of concerns for the local and global environment, for energy security and for sustainability. Thus in the years between the first and this third edition, most renewable energy technologies have grown from fledgling impact to s

90Sr- 90Y and 89Sr beta radioactivity measurement in milk samples using a proportional counter

International Nuclear Information System (INIS)

Mananes, A.; Perez Santos, C.; Martinez Churiaque, F.

1987-01-01

A thin window glas flow proportional counter is used to measure the 90 Sr- 90 Y and 89 Sr beta radioactivity in milk samples. A chemical procedure is used to separate strontium-yttrium from the other radionuclides present in milk. A calculation of the total efficiency of the system is performed which includes an empirical estimation of the backscattering factor. The calibration of the whole process allows the determination of the 90 Sr activity within 10% relative error in spite of uncertainties in the recovery yields of strontium and yttrium. No 89 Sr activity has been detected, and the mean value obtained for the 90 Sr activity in nine milk samples of Cantabria is 0.115 Bq/1 with a minimum detectable activity of 0.0105 Bq. (author) 18 refs

Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO3)n films by means of metalorganic aerosol deposition

International Nuclear Information System (INIS)

Jungbauer, M.; Hühn, S.; Moshnyaga, V.; Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G.

2014-01-01

We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO 3 ) n (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO 3 (001) substrates by means of a sequential deposition of Sr-O/Ti-O 2 atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO 3 ) 4 block at the level of 2.4%. This identifies the SrTiO 3 substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy

Renewable energy annual 1995

International Nuclear Information System (INIS)

1995-12-01

The Renewable Energy Annual 1995 is the first in an expected series of annual reports the Energy Information Administration (EIA) intends to publish to provide a comprehensive assessment of renewable energy. This report presents the following information on the history, status, and prospects of renewable energy data: estimates of renewable resources; characterizations of renewable energy technologies; descriptions of industry infrastructures for individual technologies; evaluations of current market status; and assessments of near-term prospects for market growth. An international section is included, as well as two feature articles that discuss issues of importance for renewable energy as a whole. The report also contains a number of technical appendices and a glossary. The renewable energy sources included are biomass (wood), municipal solid waste, biomass-derived liquid fuels, geothermal, wind, and solar and photovoltaic

Renewable energy annual 1995

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-01

The Renewable Energy Annual 1995 is the first in an expected series of annual reports the Energy Information Administration (EIA) intends to publish to provide a comprehensive assessment of renewable energy. This report presents the following information on the history, status, and prospects of renewable energy data: estimates of renewable resources; characterizations of renewable energy technologies; descriptions of industry infrastructures for individual technologies; evaluations of current market status; and assessments of near-term prospects for market growth. An international section is included, as well as two feature articles that discuss issues of importance for renewable energy as a whole. The report also contains a number of technical appendices and a glossary. The renewable energy sources included are biomass (wood), municipal solid waste, biomass-derived liquid fuels, geothermal, wind, and solar and photovoltaic.

Strontium, nickel, cadmium, and lead substitution into calcite, studied by density functional theory

DEFF Research Database (Denmark)

Andersson, Martin Peter; Sakuma, Hiroshi; Stipp, Susan Louise Svane

2014-01-01

We have used density functional theory to predict the ion exchange energies for divalent cations Ni(2+), Sr(2+), Cd(2+), and Pb(2+) into a calcite {10.4} surface in equilibrium with water. Exchange energies were calculated for substitution into the topmost surface layer, at the mineral-fluid inte......We have used density functional theory to predict the ion exchange energies for divalent cations Ni(2+), Sr(2+), Cd(2+), and Pb(2+) into a calcite {10.4} surface in equilibrium with water. Exchange energies were calculated for substitution into the topmost surface layer, at the mineral...

Contribution of Renewable Cooling to the Renewable Energy Target of the EU. Policy report

Energy Technology Data Exchange (ETDEWEB)

Kenkmann, T.; Buerger, V. [The Oeko-Institut, Freiburg (Germany)

2012-06-15

Renewable cooling technologies do not play a major role in the climate protection discussion in the European Union today. At the same time the cooling demand is expected to increase significantly in the coming decades. Renewable cooling technologies could contribute to the EU renewable energy target if an appropriate political framework for a further spread of the technologies is created. This renewable cooling policy report intends to support the dissemination of renewable cooling technologies. It provides an overview of the situation, technologies and potential for cool-ing from renewable sources and identifies key areas in which further investigation is required. The report shows that there is a great need for the creation of a political framework supporting the market diffusion of renewable cooling technologies. Firstly the question of a commonly accepted definition on renewable cooling is being addressed. Secondly renewable cooling technologies are described and the today's role of cooling in European statistics and policies is analysed. In the next step existing studies are evaluated to compare the expected development of the cooling demand in Europe to the market potential of renewable cooling. At the end of the paper a long-term vision for renewable cooling is described and first steps towards a European roadmap for renewable cooling are given.

License renewal process

International Nuclear Information System (INIS)

Fable, D.; Prah, M.; Vrankic, K.; Lebegner, J.

2004-01-01

The purpose of this paper is to provide information about license renewal process, as defined by Nuclear Regulatory Commission (NRC). The Atomic Energy Act and NRC regulations limit commercial power reactor licenses to an initial 40 years but also permit such licenses to be renewed. This original 40-year term for reactor licenses was based on economic and antitrust considerations not on limitations of nuclear technology. Due to this selected time period; however, some structures and components may have been engineered on the basis of an expected 40-year service life. The NRC has established a timely license renewal process and clear requirements codified in 10 CFR Part 51 and 10 CFR Part 54, that are needed to assure safe plant operation for extended plant life. The timely renewal of licenses for an additional 20 years, where appropriate to renew them, may be important to ensuring an adequate energy supply during the first half of the 21st Century. License renewal rests on the determination that currently operating plants continue to maintain adequate levels of safety, and over the plant's life, this level has been enhanced through maintenance of the licensing bases, with appropriate adjustments to address new information from industry operating experience. Additionally, NRC activities have provided ongoing assurance that the licensing bases will continue to provide an acceptable level of safety. This paper provides additional discussion of license renewal costs, as one of key elements in evaluation of license renewal justifiability. Including structure of costs, approximately value and two different approaches, conservative and typical. Current status and position of Nuclear Power Plant Krsko, related to license renewal process, will be briefly presented in this paper. NPP Krsko is designed based on NRC Regulations, so requirements from 10 CFR 51, and 10 CFR 54, are applicable to NPP Krsko, as well. Finally, this paper will give an overview of current status of

Peculiarities of Sr-90 migration in the environment

International Nuclear Information System (INIS)

Romanov, G.N.; Stukin, D.A.; Aleksakhin, R.M.

1991-01-01

The Eastern Urals radioactive track which formed as a result of the Kyshtym accident constituted a natural experimental base for studying the dynamics of Sr-90 behaviour and migration in the environment. Sr-90 behaviour in soil depends on the processes involved in its physical migration horizontally (water runoff, wind transport) and vertically (effective diffusion), on the intensity with which the physico-chemical forms of strontium change, and primarily on Sr-90 incorporation into the soil-absorptive complex. Over 30 years the effective diffusion processes led to downward displacement of Sr-90 in undisturbed soil to a depth of 30 to 50 cm. In 1988 84-94% of the Sr-90 was located in the 10 cm layer as against 90% in the 2 cm layer in the initial 1 or 2 years. The amount of Sr-90 in mobile forms in leached chernozem and grey forest soil hardly changed over time, amounting to between 76 and 90%. In the first 5-10 years Sr-90 surface water runoff was about 0.2% (and Sr-90 wind resuspension 0.1-1.0%) per year of the Sr-90 inventory per unit area. Due to Sr-90 loss from the top soil layer the water runoff and wind resuspension processes decreased exponentially, halving every 4 to 5 years. In most cases, Sr-90 transfer from soil to plants via the roots does not involve discrimination of Sr-90 with regard to calcium, and therefore the Sr-90 accumulation level in various species of natural and agricultural plants depends on their calcium requirements and the amount of exchangeable calcium in the soil. This made it possible to work out quantitative indices for forecasting Sr-90 accumulation in various species of plants for given types of soil. As Sr-90 moves through the trophic chains (including the agricultural one) we find - depending on whether two adjoining links discriminate against it or not as regards calcium - that some organisms reject it while others concentrate it. When restoring farming on the contaminated territory the fact that cattle discriminated against Sr

Applicability of 87Sr/86Sr in examining return flow of irrigation water in highly agricultural watersheds in Japan

Science.gov (United States)

Yoshida, T.; Nakano, T.; Shin, K. C.; Tsuchihara, T.; Miyazu, S.; Kubota, T.

2017-12-01

Water flows in watersheds containing extensive areas of irrigated paddies are complex because of the substantial volumes involved and the repeated cycles of water diversion from, and return to, streams. For better management of low-flow conditions, numerous studies have attempted to quantify the return flow using the stable isotopes of water; however, the temporal variation in these isotopic compositions due to fractionation during evaporation from water surfaces hinders their application to watersheds with extensive irrigated paddies. In this study, we tested the applicability of the strontium isotopes (87Sr/86Sr, hereafter Sr ratio) for studying hydrological processes in a typical agricultural watershed located on the alluvial fan of the Kinu River, namely the Gogyo River, in central Japan. The Sr ratio of water changes only because of interactions with the porous media it flows through, or because of mixing with water that has different Sr ratios. We sampled water both at a single rice paddy, and on the watershed scale in the irrigated and non-irrigated periods. The soil water under the paddy decreased as sampling depth increased, and the soil water at a depth of 1.5 m showed a similar Sr ratio to the spring. The water sampled in the drainage channel with a concrete lined bottom showed a similar Sr ratio to the irrigation water, whereas that with a soil bottom was plotted between the plots of the irrigation water and shallow aquifer. These results suggest the Sr ratio decreases as it mixes with the soil water through percolation; whereas the Sr ratio will be less likely to change when water drains from paddies via surface pathways. The streamflow samples were plotted linearly on the Sr ratio and 1/Sr plot, indicating that the streamflow was composed of two end-members; the irrigation water and the shallow aquifer. The continuous decline in the Sr ratio along the stream suggests an exfiltration of water from the shallow aquifers. The stream water during the non

Renewable energy resources

DEFF Research Database (Denmark)

Ellabban, Omar S.; Abu-Rub, Haitham A.; Blaabjerg, Frede

2014-01-01

Electric energy security is essential, yet the high cost and limited sources of fossil fuels, in addition to the need to reduce greenhouse gasses emission, have made renewable resources attractive in world energy-based economies. The potential for renewable energy resources is enormous because...... they can, in principle, exponentially exceed the world's energy demand; therefore, these types of resources will have a significant share in the future global energy portfolio, much of which is now concentrating on advancing their pool of renewable energy resources. Accordingly, this paper presents how...... renewable energy resources are currently being used, scientific developments to improve their use, their future prospects, and their deployment. Additionally, the paper represents the impact of power electronics and smart grid technologies that can enable the proportionate share of renewable energy...

A comprehensive study of magnetic exchanges in the layered oxychalcogenides Sr 3 Fe 2 O 5 Cu 2 Q 2 ( Q = S, Se)

Energy Technology Data Exchange (ETDEWEB)

Lü, Minfeng; Mentré, Olivier; Gordon, Elijah E.; Whangbo, Myung-Hwan; Wattiaux, Alain; Duttine, Mathieu; Tiercelin, Nicolas; Kabbour, Houria

2017-12-01

The layered oxysulfide Sr3Fe2O5Cu2S2 was prepared, and its crystal structure and magnetic properties were characterized by synchrotron X-ray diffraction (XRD), powder neutron diffraction (PND), Mössbauer spectroscopy measurements and by density functional theory (DFT) calculations. In addition, the spin exchange interactions leading to the ordered magnetic structure of Sr3Fe2O5Cu2S2 were compared with those of its selenium analogue Sr3Fe2O5Cu2Se2. The oxysulfide Sr3Fe2O5Cu2S2 adopts a G-type antiferromagnetic (AFM) structure at a temperature in the range 485–512 K, which is comparable with the three-dimensional (3D) AFM ordering temperature, TN ≈ 490 K, found for Sr3Fe2O5Cu2Se2. Consistent with this observation, the spin exchange interactions of the magnetic (Sr3Fe2O5)2+ layers are slightly greater (but comparable) for oxysulfide than for the oxyselenide. Attempts to reduce or oxidize Sr3Fe2O5Cu2S2 using topochemical routes yield metallic Fe.

Charge transfer mechanism for the formation of metallic states at the KTaO3/SrTiO3 interface

KAUST Repository

Nazir, Safdar; Schwingenschlö gl, Udo; Singh, Nirpendra

2011-01-01

The electronic and optical properties of the KTaO3/SrTiO3 heterointerface are analyzed by the full-potential linearized augmented plane-wave approach of density functional theory. Optimization of the atomic positions points at subordinate changes

A method for the efficient prioritization of infrastructure renewal projects

International Nuclear Information System (INIS)

Karydas, D.M.; Gifun, J.F.

2006-01-01

The infrastructure renewal program at MIT consists of a large number of projects with an estimated budget that could approach $1 billion. Infrastructure renewal at the Massachusetts Institute of Technology (MIT) is the process of evaluating and investing in the maintenance of facility systems and basic structure to preserve existing campus buildings. The selection and prioritization of projects must be addressed with a systematic method for the optimal allocation of funds and other resources. This paper presents a case study of a prioritization method utilizing multi-attribute utility theory. This method was developed at MIT's Department of Nuclear Engineering and was deployed by the Department of Facilities after appropriate modifications were implemented to address the idiosyncrasies of infrastructure renewal projects and the competing criteria and constraints that influence the judgment of the decision-makers. Such criteria include minimization of risk, optimization of economic impact, and coordination with academic policies, programs, and operations of the Institute. A brief overview of the method is presented, as well as the results of its application to the prioritization of infrastructure renewal projects. Results of workshops held at MIT with the participation of stakeholders demonstrate the feasibility of the prioritization method and the usefulness of this approach

Renewable Electricity Futures Study. Volume 1: Exploration of High-Penetration Renewable Electricity Futures

Energy Technology Data Exchange (ETDEWEB)

Mai, T.; Wiser, R.; Sandor, D.; Brinkman, G.; Heath, G.; Denholm, P.; Hostick, D.J.; Darghouth, N.; Schlosser, A.; Strzepek, K.

2012-06-01

The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%-90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT).

Half metallic ferromagnetism in tri-layered perovskites Sr{sub 4}T{sub 3}O{sub 10}(T = Co, Rh)

Energy Technology Data Exchange (ETDEWEB)

Ghimire, Madhav Prasad, E-mail: ghimire.mpg@gmail.com [Faculty of Science, Nepal Academy of Science and Technology, P. O. Box 3323, Khumaltar, Lalitpur (Nepal); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba 305-0044 (Japan); Thapa, R. K.; Sandeep [Department of Physics, Mizoram University, Aizawl 796-004 (India); Rai, D. P. [Department of Physics, Pachhunga University College, Aizawl 796-001 (India); Sinha, T. P. [Department of Physics, Bose Institute, Kolkata 700-009 (India); Hu, Xiao [International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science, Tsukuba 305-0044 (Japan)

2015-02-14

First-principles density functional theory (DFT) is used to investigate the electronic and magnetic properties of Sr{sub 4}Rh{sub 3}O{sub 10}, a member of the Ruddlesden-Popper series. Based on the DFT calculations taking into account the co-operative effect of Coulomb interaction (U) and spin-orbit couplings (SOC), Sr{sub 4}Rh{sub 3}O{sub 10} is found to be a half metallic ferromagnet (HMF) with total magnetic moment μ{sub tot} = 12 μ{sub B} per unit cell. The material has almost 100% spin-polarization at the Fermi level despite of sizable SOC. Replacement of Rh atom by the isovalent Co atom is considered. Upon full-replacement of Co, a low-spin to intermediate spin transition happens resulting in a HMF state with the total magnetic moment three-time larger (i.e., μ{sub tot} = 36 μ{sub B} per unit cell), compared to Sr{sub 4}Rh{sub 3}O{sub 10}. We propose Sr{sub 4}Rh{sub 3}O{sub 10} and Sr{sub 4}Co{sub 3}O{sub 10} as candidates of half metals.

Policies for Renewable Heat

Energy Technology Data Exchange (ETDEWEB)

NONE

2012-07-01

This paper builds on IEA publications, Deploying Renewables, Principles for Effective Policies and Deploying Renewables, Best and Future Policy Practice, that discuss the 'integrated policy approach,' whereby renewable energy technologies require different support policies at different stages of their maturity pathways. The paper discusses how the integrated policy approach applies to renewable heat. It attempts to provide guidance for policy-makers on renewable heat throughout the different phases of the policy lifecycle, allowing for the specific challenges of renewable heat and needs of the many stakeholders involved. Stimulating a market for heat involves challenges that are different and, often, more difficult to overcome than in the electricity and transport sectors.

Energy Systems With Renewable Hydrogen Compared to Direct Use of Renewable Energy in Austria

International Nuclear Information System (INIS)

Gerfried Jungmeier; Kurt Konighofer; Josef Spitzer; R Haas; A Ajanovic

2006-01-01

The current Austrian energy system has a renewable energy share of 20% - 11% hydropower and 9 % biomass - of total primary energy consumption. Whereas a possible future introduction of renewable hydrogen must be seen in the context of current energy policies in Austria e.g. increase of energy efficiency and use of renewable energy, reduction of greenhouse gas emissions. The aim of the research project is a life cycle based comparison of energy systems with renewable hydrogen from hydropower, wind, photovoltaic and biomass compared to the direct use of renewable energy for combined heat and power applications and transportation services. In particular this paper focuses on the main question, if renewable energy should be used directly or indirectly via renewable hydrogen. The assessment is based on a life cycle approach to analyse the energy efficiency, the material demand, the greenhouse gas emissions and economic aspects e.g. energy costs and some qualitative aspects e.g. energy service. The overall comparison of the considered energy systems for transportation service and combined heat and electricity application shows, that renewable hydrogen might be beneficial mainly for transportation services, if the electric vehicle will not be further developed to a feasibly wide-spread application for transportation service in future. For combined heat and electricity production there is no advantage of renewable hydrogen versus the direct use of renewable energy. Conclusions for Austria are therefore: 1) renewable hydrogen is an interesting energy carrier and might play an important role in a future sustainable Austrian energy system; 2) renewable hydrogen applications look most promising in the transportation sector; 3) renewable hydrogen applications will be of low importance for combined heat and electricity applications, as existing technologies for direct use of renewable energy for heat and electricity are well developed and very efficient; 4) In a future '100

Renewable energy policy in South Africa: policy options for renewable electricity

International Nuclear Information System (INIS)

Winkler, H.

2005-01-01

Investment in renewable energy and energy efficiency is important to reduce the negative economic, social and environmental impacts of energy production and consumption in South Africa. Currently, renewable energy contributes relatively little to primary energy and even less to the consumption of commercial energy. This article examines policy options for promoting renewable electricity. Feed-in tariffs guarantee prices for developers, but lack certainty on the amount of renewable electricity such laws would deliver under local conditions. Portfolio standards set a fixed quantity, which would guarantee diversity of supply. The question is whether the incremental upfront cost to be paid by society may be unacceptably high, compared to future health and environmental benefits. A renewables obligation combines the setting of a target with a tendering process, but may be bureaucratic to administer. Neither setting targets or regulating prices alone, however, will be sufficient. Power purchase agreements, access to the grid and creating markets for green electricity are some supporting activities that should be considered. Given that renewable electricity technologies have to compete with relatively low electricity tariffs, funding will be needed. Possible sources, both locally and internationally, are identified. The extent to which these are utilised will determine the future mix of renewable energy in South Africa. (author)

Renewable energy policy in South Africa: policy options for renewable electricity

International Nuclear Information System (INIS)

Winkler, Harald

2005-01-01

Investment in renewable energy and energy efficiency is important to reduce the negative economic, social and environmental impacts of energy production and consumption in South Africa. Currently, renewable energy contributes relatively little to primary energy and even less to the consumption of commercial energy. This article examines policy options for promoting renewable electricity. Feed-in tariffs guarantee prices for developers, but lack certainty on the amount of renewable electricity such laws would deliver under local conditions. Portfolio standards set a fixed quantity, which would guarantee diversity of supply. The question is whether the incremental upfront cost to be paid by society may be unacceptably high, compared to future health and environmental benefits. A renewables obligation combines the setting of a target with a tendering process, but may be bureaucratic to administer. Neither setting targets or regulating prices alone, however, will be sufficient. Power purchase agreements, access to the grid and creating markets for green electricity are some supporting activities that should be considered. Given that renewable electricity technologies have to compete with relatively low electricity tariffs, funding will be needed. Possible sources, both locally and internationally, are identified. The extent to which these are utilised will determine the future mix of renewable energy in South Africa

Preparation and characterization of Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite for bone repair application

Directory of Open Access Journals (Sweden)

Hossein Mohammadi

2015-07-01

Full Text Available Objective(s: Hardystonite (HT is Zn-modified silicate bioceramics with promising results for bone tissue regeneration. However, HT possesses no obvious apatite formation. Thus, in this study we incorporated Sr and Ti into HT to prepare Sr-Ti-hardystonite (Sr-Ti-HT nanocomposite and evaluated its in vitro bioactivity with the purpose of developing a more bioactive bone substitute material. Materials and methods:The HT and Sr-Ti-HT were prepared by mechanical milling and subsequent heat treatment. Calcium oxide (CaO, zinc oxide (ZnO and silicon dioxide (SiO2 (all from Merck were mixed with molar ratio of 2:1:2. The mixture of powders mixture was then milled in a planetary ball mill for 20 h. In the milling run, the ball-to-powder weight ratio was 10:1 and the rotational speed was 200 rpm. After synthesis of HT, 3% nanotitanium dioxide (TiO2, Degussa and 3% strontium carbonate (SrCO3, Merck were added to HT and then the mixture was ball milled and calcined at 1150°C for 6 h. Simultaneous thermal analysis (STA, X-ray diffraction (XRD, Transmission electron microscopy (TEM and Fourier transform infra-red spectroscopy (FT-IR performed to characterize the powders. Results:XRD and FT-IR confirmed the crystal phase and silicate structure of HT and TEM images demonstrated the nanostructure of powders. Further, Sr-Ti-HT induced apatite formation and showed a higher human mesenchymal stem cell (hMSCs adhesion and proliferation compared to HT. Conclusion:Our study revealed that Sr-Ti-HT with a nanostructured crystal structure of 50 nm, can be prepared by mechanical activation to use as biomaterials for orthopedic applications.

The influence of Sr content in calcium phosphate coatings

International Nuclear Information System (INIS)

Lindahl, Carl; Pujari-Palmer, Shiuli; Hoess, Andreas; Ott, Marjam; Engqvist, Håkan; Xia, Wei

2015-01-01

In this study calcium phosphate coatings with different amounts of strontium (Sr) were prepared using a biomineralization method. The incorporation of Sr changed the composition and morphology of coatings from plate-like to sphere-like morphology. Dissolution testing indicated that the solubility of the coatings increased with increased Sr concentration. Evaluation of extracts (with Sr concentrations ranging from 0 to 2.37 μg/mL) from the HA, 0.06Sr, 0.6Sr, and 1.2Sr coatings during in vitro cell cultures showed that Sr incorporation into coatings significantly enhanced the ALP activity in comparison to cells treated with control and HA eluted media. These findings show that calcium phosphate coatings could promote osteogenic differentiation even in a low amount of strontium. - Highlights: • Calcium phosphate coating doping with low Sr contents was prepared via a biomineralization process. • The solubility of the coatings increased with increased Sr concentration. • Present findings show the potential that Sr has on promoting osteogenic differentiation even in a low amount

Renewable energy export network

International Nuclear Information System (INIS)

Anon

2000-01-01

A Renewable Energy Exporters Network (REEN) has recently been established, following a meeting of renewable energy exporters and government agencies on 30 October 2000. REEN will assist the Australian renewable energy industry to take advantage of the opportunities offered by the burgeoning global market for renewable energy goods and services. Recent estimates of the significant potential global growth is renewable energy demand have reinforced the industry and Government's view that, in the medium to long-term, growth in the Australian renewable energy industry will largely depend on capturing export market share. Expanding the export market was identified as a crucial component in the Renewable Energy Action Agenda, developed jointly by industry and Government and released in June 2000. It was estimated that, for the industry to achieve its vision of sales of $4 billion per year by 2010, exports would need to comprise approximately 50% of the forecast growth in sales. As such, the need for a specific export strategy for the Australian renewable energy industry was recognised in the Action Agenda, and the establishment of the REEN is one of the first initiatives undertaken as part of the Renewable Energy Export Strategy. The REEN comprises approximately 50 export-ready renewable energy companies, the Department of Industry, Science and Resources, Austrade, and Stage Government agencies such as NSW's Sustainable Energy Development Authority. The Export Network will operate electronically, with face-to-face meetings held as appropriate. The Department of Industry, Science and Resources will facilitate the Export Network and has published a website at www.isr.gov.au/industry/reen. The site includes: a members directory; a discussion forum; information on opportunities to showcase Australian renewable; energy products and services; and Iinks to sites containing information that may be useful to renewable energy exporters. Other actions that are being undertaken as

Charge transfer mechanism for the formation of metallic states at the KTaO3/SrTiO3 interface

KAUST Repository

Nazir, Safdar

2011-03-29

The electronic and optical properties of the KTaO3/SrTiO3 heterointerface are analyzed by the full-potential linearized augmented plane-wave approach of density functional theory. Optimization of the atomic positions points at subordinate changes in the crystal structure and chemical bonding near the interface, which is due to a minimal lattice mismatch. The creation of metallic interface states thus is not affected by structural relaxation but can be explained by charge transfer between transition metal and oxygen atoms. It is to be expected that a charge transfer is likewise important for related interfaces such as LaAlO3/SrTiO3. The KTaO3/SrTiO3 system is ideal for disentangling the complex behavior of metallic interface states, since almost no structural relaxation takes place.

Anomalous enhancement of the thermoelectric figure of merit by V co-doping of Nb-SrTiO3

KAUST Repository

Ozdogan, K.

2012-05-10

The effect of V co-doping of Nb-SrTiO3 is studied by full-potential density functional theory. We obtain a stronger increase of the carrier density for V than for Nbdopants. While in Nb-SrTiO3 a high carrier density counteracts a high thermoelectric figure of merit, the trend is inverted by V co-doping. The mechanism leading to this behavior is explained in terms of a local spin-polarization introduced by the V ions. Our results indicate that magnetic co-doping can be a prominent tool for improving the thermoelectric figure of merit.

Anomalous enhancement of the thermoelectric figure of merit by V co-doping of Nb-SrTiO3

KAUST Repository

Ozdogan, K.; Alshareef, Husam N.; Schwingenschlö gl, Udo; Upadhyay Kahaly, M.

2012-01-01

The effect of V co-doping of Nb-SrTiO3 is studied by full-potential density functional theory. We obtain a stronger increase of the carrier density for V than for Nbdopants. While in Nb-SrTiO3 a high carrier density counteracts a high thermoelectric figure of merit, the trend is inverted by V co-doping. The mechanism leading to this behavior is explained in terms of a local spin-polarization introduced by the V ions. Our results indicate that magnetic co-doping can be a prominent tool for improving the thermoelectric figure of merit.

The impacts of non-renewable and renewable energy on CO2 emissions in Turkey.

Science.gov (United States)

Bulut, Umit

2017-06-01

As a result of great increases in CO 2 emissions in the last few decades, many papers have examined the relationship between renewable energy and CO 2 emissions in the energy economics literature, because as a clean energy source, renewable energy can reduce CO 2 emissions and solve environmental problems stemming from increases in CO 2 emissions. When one analyses these papers, he/she will observe that they employ fixed parameter estimation methods, and time-varying effects of non-renewable and renewable energy consumption/production on greenhouse gas emissions are ignored. In order to fulfil this gap in the literature, this paper examines the effects of non-renewable and renewable energy on CO 2 emissions in Turkey over the period 1970-2013 by employing fixed parameter and time-varying parameter estimation methods. Estimation methods reveal that CO 2 emissions are positively related to non-renewable energy and renewable energy in Turkey. Since policy makers expect renewable energy to decrease CO 2 emissions, this paper argues that renewable energy is not able to satisfy the expectations of policy makers though fewer CO 2 emissions arise through production of electricity using renewable sources. In conclusion, the paper argues that policy makers should implement long-term energy policies in Turkey.

Analysis of renewable energy projects' implementation in Russia

Science.gov (United States)

Ratner, S. V.; Nizhegorodtsev, R. M.

2017-06-01

With the enactment in 2013 of a renewable energy scheme by contracting qualified power generation facilities working on renewable energy sources (RES), the process of construction and connection of such facilities to the Federal Grid Company has intensified in Russia. In 2013-2015, 93 projects of solar, wind, and small hydropower energy were selected on the basis of competitive bidding in the country with the purpose of subsequent support. Despite some technical and organizational problems and a time delay of some RES projects, in 2014-2015 five solar generating facilities with total capacity of 50 MW were commissioned, including 30 MW in Orenburg oblast. However, the proportion of successful projects is low and amounts to approximately 30% of the total number of announced projects. The purpose of this paper is to analyze the experience of implementation of renewable energy projects that passed through a competitive selection and gained the right to get a partial compensation for the construction and commissioning costs of RES generating facilities in the electric power wholesale market zone. The informational background for the study is corporate reports of project promoters, analytical and information materials of the Association NP Market Council, and legal documents for the development of renewable energy. The methodological base of the study is a theory of learning curves that assumes that cost savings in the production of high-tech products depends on the production growth rate (economy of scale) and gaining manufacturing experience (learning by doing). The study has identified factors that have a positive and a negative impact on the implementation of RES projects. Improvement of promotion measures in the renewable energy development in Russia corresponding to the current socio-economic situation is proposed.

Structural and electronic behavior of Sr2GdRuO6 complex perovskite

International Nuclear Information System (INIS)

Corredor, L.T.; Velasco Zarate, J.; Landinez Tellez, D.A.; Fajardo, F.; Arbey Rodriguez M, J.; Roa-Rojas, J.

2009-01-01

We report experimental and theoretical study of crystallographic lattice and electronic structure of Sr 2 GdRuO 6 complex perovskite, which is used as precursor in the fabrication process of superconducting ruthenocuprate RuSr 2 GdCu 2 O 8 . Samples were produced by the standard solid state reaction. Rietveld refinement of experimental X-ray diffraction patterns shows that material crystallizes in a monoclinic structure, which belongs to the P2 1 /n (no.14) space group, with lattice parameters a=5.8019(6)A, b=5.8296(5)A, c=8.2223(7)A, and tilt angle β=90.258 deg. Calculations of electronic structure were performed by the density functional theory. The exchange and correlation potentials were included through the LDA+U approximation. Density of states (DOS) study was carried out considering the two spin polarizations. Results show Gd are majority responsible for the magnetic character in this material, but Ru contribution is also relevant because d-orbital is closer to Fermi level. Theoretical results evidence that Sr 2 GdRuO 6 material behaves as a magnetic semiconductor, with 20μ B effective magnetic moment.

A Theory of Continuous Socialization for Organizational Renewal

Science.gov (United States)

Danielson, Monica Marie

2004-01-01

Current literature suggests that for sustained competitive success, organizations must have processes in place for continuous learning and adaptation. Any process, then, that appears to hinder agility should come under scrutiny. Examination of socialization theories revealed an intended outcome of perpetuating the organization's way of life, its…

The inverse F-BAR domain protein srGAP2 acts through srGAP3 to modulate neuronal differentiation and neurite outgrowth of mouse neuroblastoma cells.

Directory of Open Access Journals (Sweden)

Yue Ma

Full Text Available The inverse F-BAR (IF-BAR domain proteins srGAP1, srGAP2 and srGAP3 are implicated in neuronal development and may be linked to mental retardation, schizophrenia and seizure. A partially overlapping expression pattern and highly similar protein structures indicate a functional redundancy of srGAPs in neuronal development. Our previous study suggests that srGAP3 negatively regulates neuronal differentiation in a Rac1-dependent manner in mouse Neuro2a cells. Here we show that exogenously expressed srGAP1 and srGAP2 are sufficient to inhibit valporic acid (VPA-induced neurite initiation and growth in the mouse Neuro2a cells. While ectopic- or over-expression of RhoGAP-defective mutants, srGAP1(R542A and srGAP2(R527A exert a visible inhibitory effect on neuronal differentiation. Unexpectedly, knockdown of endogenous srGAP2 fails to facilitate the neuronal differentiation induced by VPA, but promotes neurite outgrowth of differentiated cells. All three IF-BAR domains from srGAP1-3 can induce filopodia formation in Neuro2a, but the isolated IF-BAR domain from srGAP2, not from srGAP1 and srGAP3, can promote VPA-induced neurite initiation and neuronal differentiation. We identify biochemical and functional interactions of the three srGAPs family members. We propose that srGAP3-Rac1 signaling may be required for the effect of srGAP1 and srGAP2 on attenuating neuronal differentiation. Furthermore, inhibition of Slit-Robo interaction can phenocopy a loss-of-function of srGAP3, indicating that srGAP3 may be dedicated to the Slit-Robo pathway. Our results demonstrate the interplay between srGAP1, srGAP2 and srGAP3 regulates neuronal differentiation and neurite outgrowth. These findings may provide us new insights into the possible roles of srGAPs in neuronal development and a potential mechanism for neurodevelopmental diseases.

Renewable Electricity Futures Study. Volume 1. Exploration of High-Penetration Renewable Electricity Futures

Energy Technology Data Exchange (ETDEWEB)

Hand, M. M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Baldwin, S. [U.S. Dept. of Energy, Washington, DC (United States); DeMeo, E. [Renewable Energy Consulting, Chicago, IL (United States); Reilly, J. M. [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States); Mai, T. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Arent, D. [Joint Inst. for Strategic Energy Analysis, Boulder, CO (United States); Porro, G. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Meshek, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sandor, D. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2012-06-15

The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%–90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT). Learn more at the RE Futures website. http://www.nrel.gov/analysis/re_futures/

The metallic interface between the two band insulators LaGaO3 and SrTiO3

KAUST Repository

Nazir, Safdar; Schwingenschlö gl, Udo; Singh, Nirpendra

2011-01-01

The formation of metallic interface states between the two band insulators LaGaO3 and SrTiO3 is studied by the full-potential linearized augmented plane-wave method based on density functional theory.Structural optimization of the atomic positions points to only small changes of the chemical bonding at the interface. The n-type (LaO/TiO2) and p-type (GaO2/SrO) interfaces turn out to be metallic. Reduction of the O content increases the conductivity of the n-type interface, while the p-type interface can be turned gradually from a hole doped into an electron doped state.

The metallic interface between the two band insulators LaGaO3 and SrTiO3

KAUST Repository

Nazir, Safdar

2011-06-28

The formation of metallic interface states between the two band insulators LaGaO3 and SrTiO3 is studied by the full-potential linearized augmented plane-wave method based on density functional theory.Structural optimization of the atomic positions points to only small changes of the chemical bonding at the interface. The n-type (LaO/TiO2) and p-type (GaO2/SrO) interfaces turn out to be metallic. Reduction of the O content increases the conductivity of the n-type interface, while the p-type interface can be turned gradually from a hole doped into an electron doped state.

Mapping and characterization of wheat stem rust resistance genes SrTm5 and Sr60 from Triticum monococcum.

Science.gov (United States)

Chen, Shisheng; Guo, Yan; Briggs, Jordan; Dubach, Felix; Chao, Shiaoman; Zhang, Wenjun; Rouse, Matthew N; Dubcovsky, Jorge

2018-03-01

The new stem rust resistance gene Sr60 was fine-mapped to the distal region of chromosome arm 5A m S, and the TTKSK-effective gene SrTm5 could be a new allele of Sr22. The emergence and spread of new virulent races of the wheat stem rust pathogen (Puccinia graminis f. sp. tritici; Pgt), including the Ug99 race group, is a serious threat to global wheat production. In this study, we mapped and characterized two stem rust resistance genes from diploid wheat Triticum monococcum accession PI 306540. We mapped SrTm5, a previously postulated gene effective to Ug99, on chromosome arm 7A m L, completely linked to Sr22. SrTm5 displayed a different race specificity compared to Sr22 indicating that they are distinct. Sequencing of the Sr22 homolog in PI 306540 revealed a novel haplotype. Characterization of the segregating populations with Pgt race QFCSC revealed an additional resistance gene on chromosome arm 5A m S that was assigned the official name Sr60. This gene was also effective against races QTHJC and SCCSC but not against TTKSK (a Ug99 group race). Using two large mapping populations (4046 gametes), we mapped Sr60 within a 0.44 cM interval flanked by sequenced-based markers GH724575 and CJ942731. These two markers delimit a 54.6-kb region in Brachypodium distachyon chromosome 4 and a 430-kb region in the Chinese Spring reference genome. Both regions include a leucine-rich repeat protein kinase (LRRK123.1) that represents a potential candidate gene. Three CC-NBS-LRR genes were found in the colinear Brachypodium region but not in the wheat genome. We are currently developing a Bacterial Artificial Chromosome library of PI 306540 to determine which of these candidate genes are present in the T. monococcum genome and to complete the cloning of Sr60.

Growth with Endogenous Capital, Knowledge, and Renewable Resources

Directory of Open Access Journals (Sweden)

Wei-Bin Zhang

2017-03-01

Full Text Available This paper proposes a dynamic economic model with endogenous technological change, physical capital and renewable resources. The model is a synthesis of the neoclassical growth theory, Arrow’s learning by doing, and some traditional dynamic models of renewable resources with an alternative approach to household behavior. The model describes a dynamic interdependence between technological change, physical accumulation, resource change, and division of labor under perfect competition. Because of its refined economic structure, the model analyzes some interactions between economic variables which are not found in the existing literature of economic growth. We simulate the model to demonstrate existence of equilibrium points and motion of the dynamic system. Our comparative dynamic analysis shows, for instance, that a rise in the capacity of the renewable resource increases the stock and reduces the price of the resource of the resource over time; the output levels of the two sectors, the total capital stock, and capital inputs of the two sectors are all increased; the labor distribution between the two sectors is slightly affected initially but is not affected in the long term; the rate of interest rises initially rise and is almost not affected in the long term; the per capita consumption levels of the good and the resource and the wage rate are increased.

Chernobyl 90Sr in bilberries from Poland

International Nuclear Information System (INIS)

Mietelski, J.W.; Vajda, N.

1997-01-01

As part of a detailed survey on the contamination of Polish forests 90 Sr activity concentrations were determined in bilberries. Elevated 90 Sr levels were found in several samples from north-eastern Poland. The calculated maximum 90 Sr surface contamination was 2 kBq*m -2 . The correlation between 90 Sr and 137 Cs concentrations in bilberries was good for two sets of samples originating from two geographical areas of Poland indicating the local differences in radionuclide depositions from Chernobyl fallout. (author)

Uncertainty analysis of 137Cs and 90Sr activity in borehole water from a waste disposal site

International Nuclear Information System (INIS)

Dafauti, Sunita; Pulhani, Vandana; Datta, D.; Hegde, A.G.

2005-01-01

Uncertainty quantification (UQ) is the quantitative characterization and use of uncertainty in experimental applications. There are two distinct types of uncertainty variability which can be quantified in principle using classical probability theory and lack of knowledge which requires more than classical probability theory for its quantification. Fuzzy set theory was applied to quantify the second type of uncertainty associated with the measurement of activity due to 137 Cs and 90 Sr present in bore-well water samples from a waste disposal site. The upper and lower limits of concentration were computed and it may be concluded from the analysis that the alpha cut technique of fuzzy set theory is a good nonprecise estimator of these types of bounds. (author)

Modification of Sr on 4004 Aluminum Alloy

Science.gov (United States)

Guo, Erjun; Cao, Guojian; Feng, Yicheng; Wang, Liping; Wang, Guojun; Lv, Xinyu

2013-05-01

As a brazing foil, 4004 Al alloy has good welding performance. However, the high Si content decreases the plasticity of the alloy. To improve the plasticity of 4004 Al alloy and subsequently improve the productivity of 4004 Al foil or 434 composite foil, 4004 Al alloy was modified by Al-10%Sr master alloy. Modification effects of an additional amount of Sr, modification temperature, and holding time on 4004 aluminum alloy were studied by orthogonal design. The results showed that the greatest impact parameter of 4004 aluminum alloy modification was the additional amount of Sr, followed by holding time and modification temperature. The optimum modification parameters obtained by orthogonal design were as follows: Sr addition of 0.04%, holding time of 60 min, and modification temperature of 760°C. The effect of Sr addition on modification was analyzed in detail based on orthogonal results. With increasing of Sr addition, elongation of 4004 alloy increased at first, and decreased after reaching the maximum value.

Losses of Sr/sup 90/, Sr/sup 89/, and I/sup 131/ from fallout-contaminated plants

Energy Technology Data Exchange (ETDEWEB)

Martin, W E

1964-11-01

During the early period following local fallout, and during periods of maximal worldwide fallout, the entry of radionuclides into terrestrial food-chains is due primarily to the external contamination of plants and secondarily to the uptake of radionuclides from contaminated soil. Studies were undertaken to estimate the rates of radionuclide loss from fallout-contaminated vegetation and hence from the diets of herbivores living in a fallout field. On the fifth, fifteenth, thirtieth, and sixtieth days after an underground nuclear explosion (Operation Sedan) at the Nevada Test Site, plant samples were collected from twenty representative locations in the fallout field and analyzed to determined the concentrations (pc/g dry wt) of /sup 90/Sr, /sup 89/Sr, and /sup 131/I at the times of collections. While the radioactive half lives of /sup 90/Sr, /sup 89/Sr, and /sup 131/I are approximately 27.7 years, 53 days, and 8.04 days respectively, their average effective half-lives on fallout-contaminated plants, during the period from 5 to 30 days after the detonation, were 27.8 days, 17.8 days, and 5.0 days respectively. Losses of /sup 90/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 90/Sr and /sup 89/Sr were attributed to radioactive decay and to the removal of fallout particles and foliage by wind and/or other mechanical disturbances. Losses of /sup 131/I were attributed to radioactive decay, to mechanical disturbance, and to the vaporization of /sup 131/I from the fallout particles retained on foliage.

High charge carrier density at the NaTaO3/SrTiO3 hetero-interface

KAUST Repository

Nazir, Safdar

2011-08-05

The formation of a (quasi) two-dimensional electron gas between the band insulators NaTaO3 and SrTiO3 is studied by means of the full-potential linearized augmented plane-wave method of density functional theory. Optimization of the atomic positions points to only small changes in the chemical bonding at the interface. Both the p-type (NaO)−/(TiO2)0 and n-type (TaO2)+/(SrO)0 interfaces are found to be metallic with high charge carrier densities. The effects of O vacancies are discussed. Spin-polarized calculations point to the formation of isolated O 2pmagnetic moments, located in the metallic region of the p-type interface.

Adsorption and Electronic Structure of Sr and Ag Atoms on Graphite Surfaces: a First-Principles Study

Science.gov (United States)

Luo, Xiao-Feng; Fang, Chao; Li, Xin; Lai, Wen-Sheng; Sun, Li-Feng; Liang, Tong-Xiang

2013-06-01

The adsorption behaviors of radioactive strontium and silver nuclides on the graphite surface in a high-temperature gas-cooled reactor are studied by first-principles theory using generalized gradient approximation (GGA) and local density approximation (LDA) pseudo-potentials. It turns out that Sr prefers to be absorbed at the hollow of the carbon hexagonal cell by 0.54 eV (GGA), while Ag likes to sit right above the carbon atom with an adsorption energy of almost zero (GGA) and 0.45 eV (LDA). Electronic structure analysis reveals that Sr donates its partial electrons of the 4p and 5s states to the graphite substrate, while Ag on graphite is a physical adsorption without any electron transfer.

Determination of the shape factor of 90Sr by means of the cutoff energy yield method

International Nuclear Information System (INIS)

Grau Carles, A.; Kossert, K.; Grau Malonda, A.

2008-01-01

Usually, Kurie plots are used to analyze beta-spectra shape-factor functions measured by means of semiconductor and magnetic spectrometers. A drawback of these techniques is the occurrence of self-absorption within the samples through which the emission spectrum is altered. In liquid-scintillation samples self-absorption does not occur, but the poor energy resolution makes the analysis of the spectra difficult. To overcome this problem, two resolution-invariant observables are used for determining the shape-factor function of 90 Sr: (1) the maximum point energy and (2) the cutoff energy yield. The measured shape-factor function of 90 Sr agrees with the one which is predicted by theory for the first-forbidden unique transition

Metal-insulator transition at the LaAlO3/SrTiO3 interface revisited: A hybrid functional study

KAUST Repository

Cossu, Fabrizio; Eyert, V.; Schwingenschlö gl, Udo

2013-01-01

We investigate the electronic properties of the LaAlO3/SrTiO3 interface using density functional theory. In contrast to previous studies, which relied on (semi-)local functionals and the GGA+U method, we here use a recently developed hybrid

Experimental evidence shows no fractionation of strontium isotopes ((87)Sr/(86)Sr) among soil, plants, and herbivores: implications for tracking wildlife and forensic science.

Science.gov (United States)

Flockhart, D T Tyler; Kyser, T Kurt; Chipley, Don; Miller, Nathan G; Norris, D Ryan

2015-01-01

Strontium isotopes ((87)Sr/(86)Sr) can be useful biological markers for a wide range of forensic science applications, including wildlife tracking. However, one of the main advantages of using (87)Sr/(86)Sr values, that there is no fractionation from geological bedrock sources through the food web, also happens to be a critical assumption that has never been tested experimentally. We test this assumption by measuring (87)Sr/(86)Sr values across three trophic levels in a controlled greenhouse experiment. Adult monarch butterflies were raised on obligate larval host milkweed plants that were, in turn, grown on seven different soil types collected across Canada. We found no significant differences between (87)Sr/(86)Sr values in leachable Sr from soil minerals, organic soil, milkweed leaves, and monarch butterfly wings. Our results suggest that strontium isoscapes developed from (87)Sr/(86)Sr values in bedrock or soil may serve as a reliable biological marker in forensic science for a range of taxa and across large geographic areas.

Electronic structure calculation of Sr2CoWO6 double perovskite using DFT+U

Science.gov (United States)

Mandal, Golak; Jha, Dhiraj; Himanshu, A. K.; Ray, Rajyavardhan; Mukherjee, P.; Das, Nisith; Singh, B. K.; Sreenivas, K.; Singh, M. N.; Sinha, A. K.

2018-04-01

Using the synchrotron and Raman spectroscopy we measured the lattice parameter and Raman modes of the half-metallic (HM) Sr2CoWO6 (SCoW) synthesied by the solid state reaction technique.. The physical properties of SCoW are studies within the framework of density function theory (DFT) under the generalised gradient approximation (GGA) of Perdew, Bruke, and Ernzerhof both by itself and including a coulomb repulsion via the Hubbard approach or GGA+U. Our results states that Sr2CoWO6 material behaves as insulators for the spin-up orientation and spindown orientation as found for the half metallic systems and at U = 0.06eV the ground state of spin up channel being insulating with spin gap of 2.27eV comparable to the experimental Band gap (BG).

Renewal after the punishment of free operant behavior.

Science.gov (United States)

Bouton, Mark E; Schepers, Scott T

2015-01-01

Three experiments examined the role of context in punishment learning. In Experiment 1, rats were trained to lever press for food in Context A and then punished for responding in Context B (by presenting response-contingent footshock). Punishment led to complete suppression of the response. However, when responding was tested (in extinction) in Contexts A and B, a strong renewal of responding occurred in Context A. In Experiment 2, renewal also occurred when initial reinforcement occurred in Context A, punishment occurred in Context B, and testing occurred in a new context (Context C). In both experiments, behavioral suppression and renewal were not observed in groups that received noncontingent (yoked) footshocks in Context B. In Experiment 3, 2 responses (lever press and chain pull) were separately reinforced in Contexts A and B and then punished in the opposite context. Although the procedure equated the contexts on their association with reinforcement and punishment, renewal of each response was observed when it was tested in its nonpunished context. The contexts also influenced response choice. Overall, the results suggest that punishment is specific to the context in which it is learned, and establish that its context-specificity does not depend on a simple association between the context and shock. Like extinction, punishment may involve learning to inhibit a specific response in a specific context. Implications for theories of punishment and for understanding the cessation of problematic operant behavior (e.g., drug abuse) are discussed. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Real-time {sup 90}Sr Counter

Energy Technology Data Exchange (ETDEWEB)

Kaneko, Naomi; Kawai, Hideyuki; Kodama, Satoshi; Kobayashi, Atsushi; Tabata, Makoto; Ito, Hiroshi [Graduate School of Science, Chiba University, Chiba, (Japan); Han, Soorim [Graduate School of Science, Chiba University, Chiba, (Japan); National Institute of Radiological Science, Chiba, (Japan)

2015-07-01

Radioisotopes have been emitted around Japan due to a nuclear accident at the Fukushima Daiichi nuclear power station in March 2011. A problem is the contaminated water including the atomic nucleus which relatively has a long half- life time and soluble such as {sup 90}Sr, {sup 137}Cs. Internal exposures by {sup 90}Sr are more dangerous than {sup 137}Cs's because Sr has effective half-life time of 18 years and property of accumulation in a born. We have developed real-time {sup 90}Sr counter which is sensitive beta-ray of maximum kinematic energy of 2.28 MeV from {sup 90}Sr and insensitive of beta-ray of maximum kinematic energy of 1.17 MeV and gamma-ray from {sup 90}Sr by Cherenkov detection. This counter composes of Cerenkov counter, trigger scintillation counter and veto counter. Silica aerogel for Cherenkov counter can obtain refractive index between 1.017 and 1.049 easily. And wavelength shifting fiber (WLSF) is used as a light guide for extending effective area and producing lower cost. A mechanism of the identification of {sup 90}Sr is explained in following. In case of {sup 90}Sr, when the trigger counter reacts on the beta-ray from {sup 90}Sr, aerogel emits the Cherenkov light and WLSF reacts and read the Cherenkov light. On the other hand, in case of {sup 137}Cs, the trigger counter reacts on the beta-ray, aerogel stops the beta- ray and Cherenkov light is not emitted. Therefore, aerogel has a function as a radiator and shielding material. the gamma-ray is not reacted on the lower density detector. Cosmic rays would be also reacted by the veto counter. A prototype counter whose the effective area is 30 cm x 10 cm was obtained (2.0±1.2){sup 3} of mis-identification as {sup 137}Cs/{sup 90}Sr. Detection limit in the surface contamination inspection depends on measurement time and effective area mainly. The sensitivity of wide range, 10{sup -2} - 10{sup 4} Bq/cm{sup 2}, is obtained by adjustment of detection level in circuit of this counter. A lower

Temperature effect on the retention of U(VI) by SrTiO3

International Nuclear Information System (INIS)

Garcia Rosales, G.

2007-11-01

The purpose of this research was the study of the interaction mechanisms between U(VI) ions and SrTiO 3 surfaces versus pH and temperature: 25, 50, 75 and 90 C. Firstly, a physicochemical characterization was realized (DRX, MEB, FTIR) and the surface site density was determined. The potentiometric titration data were simulated, for each temperature, using the constant capacitance model and taking into account bath protonation of the ≡Sr-OH surface sites and deprotonation of the ≡Ti-OH ones (one pK a model). Both enthalpy and entropy changes, corresponding to the surface acid-base reactions, were evaluated using the van't Hoff relation. U(VI) was sorbed onto SrTiO 3 powder in the pH range 0.5-5.0 with an U(VI) initial concentration 1.10 -4 M. By TRLIFS two U(VI) complexes were detected associated with two lifetime values (60 ± 5 and 12 ± 2 μs at 25 C). The sorption edges were simulated using FITEQL 4.0 software. The surface complexation constants of the system SrTiO 3 /U(VI) between 25 and 90 C temperature range were thus obtained with the constant capacitance model considering two reactive surface sites. It reveals that two types of surface complex, namely [(≡SrOH)(≡TiOH)UO 2 ] 2+ and [(≡TiOH)(≡TiO)UO 2+ ] 2+ , are needed to properly describe the experimental observations. By application of the van't Hoff equation, Delta R S 0 and Delta R H 0 were obtained, which indicated an endothermic sorption process. Finally, an energy transfer study was realised by TRLIFS. The energy transfer between Tb 3+ and Eu 3+ ions sorbed onto SrTiO 3 powders were investigated. The results showed that the energy transfer between Tb 3+ and Eu 3+ is a non-radiative process and follows a dipole-dipole type interaction. A formalism based on the Dexter and the Inokuti-Hirayama theories was used to calculate the distances (2,7-3,4 Angstroms between Tb 3+ and Eu 3+ onto SrTiO 3 surface. (author)

Renewable Electricity Futures: Exploration of a U.S. Grid with 80% Renewable Electricity

Science.gov (United States)

Mai, Trieu

2013-04-01

Renewable Electricity Futures is an initial investigation of the extent to which renewable energy supply can meet the electricity demands of the contiguous United States over the next several decades. This study explores the implications and challenges of very high renewable electricity generation levels: from 30% up to 90% (focusing on 80%) of all U.S. electricity generation from renewable technologies in 2050. At such high levels of renewable electricity penetration, the unique characteristics of some renewable resources, specifically geographical distribution and variability and un-certainty in output, pose challenges to the operability of the nation's electric system. The study focuses on key technical implications of this environment from a national perspective, exploring whether the U.S. power system can supply electricity to meet customer demand on an hourly basis with high levels of renewable electricity, including variable wind and solar generation. The study also identifies some of the potential economic, environmental, and social implications of deploying and integrating high levels of renewable electricity in the U.S. The full report and associated supporting information is available at: http://www.nrel.gov/analysis/refutures/.

Report on nuclear energy in SR Slovenia; Porocilo o uporabi jedrske energije v SR Sloveniji

Energy Technology Data Exchange (ETDEWEB)

NONE

1987-07-01

Currently Yugoslavia has one 632 MWe nuclear power plant (NPP) of PWR design, located at Krsko in the Socialist Republic (SR) of Slovenia. Krsko NPP, which is a two-loop plant, started power operation in 1981. In general, reactor safety activities in the SR of Slovenia are mostly related to upgrading the safety of our Krsko NPP and to developing capabilities for use in future units. This report presents the nuclear safety related legislation and organization of the corresponding regulatory body, and the activities related to nuclear safety of the participating organizations in the SR of Slovenia in 1987.

Teaching Renewable Energy Using Online PBL in Investigating Its Effect on Behaviour towards Energy Conservation among Malaysian Students: ANOVA Repeated Measures Approach

Science.gov (United States)

Nordin, Norfarah; Samsudin, Mohd Ali; Harun, Abdul Hadi

2017-01-01

This research aimed to investigate whether online problem based learning (PBL) approach to teach renewable energy topic improves students' behaviour towards energy conservation. A renewable energy online problem based learning (REePBaL) instruction package was developed based on the theory of constructivism and adaptation of the online learning…

Renewable energy in eastern Asia: Renewable energy policy review and comparative SWOT analysis for promoting renewable energy in Japan, South Korea, and Taiwan

International Nuclear Information System (INIS)

Chen, Wei-Ming; Kim, Hana; Yamaguchi, Hideka

2014-01-01

Japan, South Korea, and Taiwan are deficient of domestic fossil energy sources and depend significantly on imported fuels. Since the oil shock in the 1970s, all three countries have promoted renewable energy as an alternative energy source to improve energy security. Currently, renewable energy is being promoted to build low-carbon economies. This study reviews the development of renewable energy policies and roadmaps. It also examines and compares strengths, weaknesses, opportunities, and threats (SWOT) of these countries in the context of advancing renewable energy policies and technologies and expanding domestic renewable energy installations, as well as strategically positioning themselves in the international renewable energy market as exporters of clean energy technologies. Through the SWOT analysis, this paper identifies a capacity for additional renewable energy deployment in these countries and highlights the necessity of increased cooperation between the three countries to strengthen their domestic and regional renewable energy sectors and compete in the global renewable energy market in the post-Fukushima era. - Highlights: • Japan, South Korea and Taiwan need to develop renewable energy (RE). • These countries have been too conservative to achieve a notable share of RE. • Pro-nuclear energy policies have hindered the RE development in these countries. • The Fukushima disaster made these countries more favorable to RE. • Joint cooperation for R and D and deployment of RE is recommended

Studying young people’ views on deployment of renewable energy sources in Iran through the lenses of Social Cognitive Theory

Directory of Open Access Journals (Sweden)

Nadejda Komendantova

2018-03-01

Full Text Available Renewable energy sources (RES have potentials to address goals of climate change mitigation at the global level. Iran has abundant RES potentials and investment into renewable energy sources can contribute to its socio-economic development and to diversification of its energy mix. Economic and technical capacities but also human factors, such as stakeholders’ views, public and social acceptance, as well as willingness to use RES, willingness to pay for their deployment and to participate in decision-making processes on energy transition, are crucial factors for deployment of RES at scale. These human factors impact development and implementation of energy transition at the national and local governance levels. Deployment of new technology and energy transition can lead to conflicting views, believes and risks perceptions among involved stakeholders but also among people affected by deployment of new technology infrastructure deployment. To be sustainable and acceptable by all social groups, such process should be based on understanding of positions of different stakeholders and development of compromise solutions. It is crucial to understand the views of young people on deployment of RES as young people represent a significant share of population and are future decision makers. Their support and willingness to use RES will be a significant driver for RES deployment in short and medium term. Based on socio cognitive theory this paper examines the patters of behavior of young adults in relation to energy use. The results show positive influence of self-rewarding to encourage young adults to participate in energy transition. Another important driver is expectation of social outcome, which involves existing social norms in the community. Trust to the source of information is another important driver and the level of information about RES has an important influence on the willingness to use them.

What drives renewable energy development?

International Nuclear Information System (INIS)

Alagappan, L.; Orans, R.; Woo, C.K.

2011-01-01

This viewpoint reviews renewable energy development in 14 markets that differ in market structure (restructured vs. not restructured), use of feed-in-tariff (FIT) (yes vs. no), transmission planning (anticipatory vs. reactive), and transmission interconnection cost allocated to a renewable generator (high vs. low). We find that market restructuring is not a primary driver of renewable energy development. Renewable generation has the highest percent of total installed capacity in markets that use a FIT, employ anticipatory transmission planning, and have loads or end-users paying for most, if not all, of the transmission interconnection costs. In contrast, renewable developers have been less successful in markets that do not use a FIT, employ reactive transmission planning, and have generators paying for most, if not all, of the transmission interconnection costs. While these policies can lead to higher penetration of renewable energy in the short run, their high cost to ratepayers can threaten the economic sustainability of renewable energy in the long-run. - Highlights: → Market structure seems to have little effect on renewable energy development. → Renewable energy development is more successful in markets that use a FIT. → Anticipatory transmission planning aids renewable energy development. → Low interconnection costs for developers also aids renewable energy development.

Sr isotopic tracer study of the Samail ophiolite, Oman

International Nuclear Information System (INIS)

Lanphere, M.A.; Coleman, R.G.; Hopson, C.A.

1981-01-01

We have measured Rb and Sr concentrations and Sr isotopic compositions in 41 whole-rock samples and 12 mineral separates from units of the Samail ophiolite, including peridotite, gabbro, plagiogranite diabase dikes, and gabbro and websterite dikes within the metamorphic peridotite. Ten samples of cummulate gabbro from the Wadir Kadir section and nine samples from the Wadi Khafifah section have mean 87 Sr/ 86 Sr ratios and standard deviations of 0.70314 +- 0.00030 and 0.70306 +- 0.00034, respectively. The dispersion in Sr isotopic composition may reflect real heterogeneities in the magma source region. The average Sr isotopic composition of cumulate gabbro falls in the range of isotopic compositions of modern midocean ridge basalt. The 87 Sr/ 86 Sr ratios of noncumulate gabbro, plagiogranite, and diabase dikes range from 0.7034 to 0.7047, 0.7038 to 0.7046, and 0.7037 to 0.7061, respectively. These higher 87 Sr/ 86 Sr ratios are due to alteration of initial magmatic compositions by hydrothermal exchange with seawater. Mineral separates from dikes that cut harzburgite tectonite have Sr isotopic compositions which agree with that of cumulate gabbro. These data indicate that the cumulate gabbro and the different dikes were derived from partial melting of source regions that had similar long-term histories and chemical compositions

Renewables Global Futures Report: Great debates towards 100% renewable energy

International Nuclear Information System (INIS)

Teske, Sven; Fattal, Alex; Lins, Christine; Hullin, Martin; Williamson, Laura E.

2017-01-01

The first version of REN21's Renewables Global Futures Report (GFR) published in January 2013 identified a panorama of likely future debates related to the renewable energy transition. As a reflection of the wide range of contemporary thinking by the many experts interviewed for the report, it did not present just one vision of the future but rather a 'mosaic' of insights. Given the positive feedback in response to the first edition, a new edition has been prepared, continuing where the last one left off. The objective of this report is to gather opinions about the feasibility of a 100% renewable energy future, and the macro-economic impacts it would entail. In so doing, the report reflects on the debates of 2013, and tracks their evolution to the present time. Some remain, some have changed, some have been overtaken by progress, and new ones have arisen. They are summarised here as the Great Debates in renewable energy. The questionnaire for the survey was developed in close cooperation between the REN21 Secretariat, the Institute for Sustainable Future (ISF) of the University of Technology Sydney/Australia (UTS) and the Institute for Advanced Sustainability Studies (IASS) in Potsdam/Germany. It covered the following topics: 1. How much renewables?; 2. Power sector; 3. Heating and cooling; 4. Transport; 5. Storage; 6. Demand-side management and energy efficiency; 7. Integration of sectors; 8. Macro-economic considerations; 9. Technology and costs; 10. Policy; 11. Cities; 12. Distributed renewable energy/energy access; 13. Barriers/challenges/enablers. 114 experts were interviewed in total; the average interview time was approximately one hour. The interviews were conducted between May and October 2016. The questionnaire was also mirrored in an online version and used both by interviewers and interviewees to record the interview process. Interviewees were selected from the following regions: Africa, Australia and Oceania, China, Europe, India, Japan, Latin America

Thermal infrared and microwave absorbing properties of SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/polyaniline nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Hosseini, Seyed Hossein, E-mail: shhosseini@iiau.ac.ir [Department of Chemistry, Faculty of Science, Islamshahr Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Zamani, Parisa [Department of Applied Chemistry, Faculty of Pharmaceutical Chemistry, Pharmaceutical Sciences Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of); Mousavi, S.Y. [Faculty of Passive Defense, Imam Hossein University, Tehran (Iran, Islamic Republic of)

2015-09-25

Graphical abstract: We have developed a new perspective of applications and properties of conducting polymers. The combination of absorption ability prepared nanocomposites in the present of PANI display a great potential in organization of shielding structures into thermal IR and microwave. Further investigations using other conducting polymers to demonstrate their capability for advance thermal IR and microwave shielding devices is under way. The application of these samples may improve the IR thermographic detection, catalysis, sensors, magnetic data storage, electromagnetic resonance wave absorption, photonic crystals, and microelectronic devices and military aspects. - Highlights: • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI exhibited electric and electromagnetic properties. • The SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI has shielding structures into thermal IR and microwave. • Increasing weight ratios and thicknesses will increase thermal IR ability. • Increasing weight ratios and thicknesses will increase microwave absorption ability. - Abstract: Polyaniline (PANI) as a unique polymer that also has electromagnetic absorption used as the substrate. In this research, SrTiO{sub 3} was synthesized as IR absorbent and core and then SrFe{sub 12}O{sub 19} as microwave absorbent was prepared on SrTiO{sub 3} via co-precipitation method as the first shell. As the next step, PANI was coated on SrTiO{sub 3}/SrFe{sub 12}O{sub 19} nanoparticles via in situ polymerization by multi core–shell structures (SrTiO{sub 3}/SrFe{sub 12}O{sub 19}/PANI). Nanometer size and structures of samples were measured by TEM, XRD and FTIR. Morphology of nanocomposite was showed by SEM images. The magnetic and electric properties were also performed by VSM and four probe techniques. Thermal infrared (IR) absorption and microwave reflection loss of nanocomposites were investigated at 10–40 μm and 8–12 GHz, IR and microwave frequencies, respectively. The results showed that the Sr

Thermodynamic properties of crystalline Sr0.5Zr2(PO4)3 phosphate from T → 0 to 665 K

International Nuclear Information System (INIS)

Pet'kov, V.I.; Markin, A.V.; Bykova, T.A.; Sukhanov, M.V.; Smirnova, N.N.; Loshkarev, V.N.

2007-01-01

The temperature dependence of the heat capacity of crystalline Sr 0.5 Zr 2 (PO 4 ) 3 phosphate was studied by precision adiabatic vacuum and dynamic scanning calorimetry over the temperature range 7-665 K. The low-temperature dependence of the heat capacity was analyzed using the Debye theory of the heat capacity of solids and its multifractal generalization, which allowed conclusions to be drawn about the heterodynamic characteristics of the structure. The experimental data obtained were used to calculate the standard thermodynamic functions of Sr 0.5 Zr 2 (PO 4 ) 3 from T → 0 to 665 K. The standard absolute entropy of Sr 0.5 Zr 2 (PO 4 ) 3 was in turn used to calculate the standard entropy of its formation from simple substances at 298.15 K [ru

82Sr--82Rb radioisotope generator

International Nuclear Information System (INIS)

Grant, P.M.; Erdal, B.R.; O'Brien, H.A.

1976-01-01

An improved 82 Sr- 82 Rb radioisotope generator system, based upon the complexing ion exchange resin Chelex-100, has been developed. Columns of this material can be easily and rapidly milked, and the Rb-Sr separation factor for a fresh generator was found to be greater than 10 7 . Approximately 80 percent of the 82 Rb present was delivered in a 15-ml volume of aqueous 0.2 M NH 4 Cl solution. After more than 6 liters of eluant had been put through the generator, the Rb-Sr separation factor was still observed to be greater than 10 5 , and no unusual strontium breakthrough behavior was seen in the system over nearly three 82 Sr half lives. 2 claims, no drawings

Mapping of renewable energies

International Nuclear Information System (INIS)

Boulanger, V.

2013-01-01

Germany is the champion of green energy in Europe: the contribution of renewable energies to electricity generation reached about 20% in 2011. This article describes the situation of renewable energies in Germany in 2011 with the help of 2 maps, the first one gives the installed electrical generation capacity for each region and for each renewable energy source (wind power, hydro-electricity, biomass, photovoltaic energy and biogas) and the second one details the total number of jobs (direct and indirect) for each renewable energy source and for each region. In 2011 about 372000 people worked in the renewable energy sector in Germany. (A.C.)

Autoradiography of 90Sr in developing rats

International Nuclear Information System (INIS)

Olsen, I.; Jonsen, J.

1979-01-01

The distribution patterns of 90 Sr in five littermate, 8-day-old Wistar rats were studied by whole body autoradiography. Rats were killed 15 min, 1, 4, 24, and 72 h after a single intraperitoneal injection of the isotope. Immediately after administration, 90 Sr was distributed throughout most of the soft tissues of the body. The soft tissue deposits had practically disappeared after 4 h. In the hard tissues of the body 90 Sr accumulated up to 24-72 h. Fifteen minutes after injection the uptake of 90 Sr in the enamel of the teeth was highest in the occlusal and incisal regions. 90 Sr gradually accumulated throughout the enamel and after 72 h its distribution in this layer was fairly uniform. Immediately after injection a narrow zone of radioactivity appeared in the dentin near the pulp. This zone broadened with time towards the dentinoenamel junction and included the intire dentin layer 72 h after injection. Initially, the uptake of 90 Sr was higher in the dentin than in the enamel, particularly in the cervical areas of the crown. This difference became less apparent with time. There was good correlation between the uptake in the teeth and bones, supporting the use of teeth as indicators of the 90 Sr body burden. (author)

Determination of 90Sr by liquid scintillation counting

International Nuclear Information System (INIS)

Cerchetti, Maria L.; Aghazarian, V.P.

2006-01-01

99m Tc, the result of the radioactive decay of 99 Mo, is one of the most applied radioisotopes in nuclear medicine and is used in nuclear medicine as a radiopharmaceutical product. It is important to ensure 99 Mo quality in order to fit the 99m Tc quality specifications. The main objective was to obtain a technique for 90 Sr determination in 99 Mo and environmental samples. The purification of 90 Sr is performed by extraction chromatography where crown-ether resin (Sr-Spec, Eichrom) was used. The measurement of the 90 Sr activity is performed by Liquid Scintillation Counting (LSC) using the double windows method. This method permits the 90 Sr determination without waiting until radiochemical equilibrium 90 Sr / 90 Y has been reached. The recovery factor was determined by gamma spectrometry with 85 Sr, and by gravimetry with stable strontium carrier solution. The minimum detectable activity was 0,05 Bq. The recovery factor was the major contribution in the total uncertainty. (author)

General Strain Theory, Peer Rejection, and Delinquency/Crime

Science.gov (United States)

Higgins, George E.; Piquero, Nicole L.; Piquero, Alex R.

2011-01-01

The development of general strain theory (GST) has led to a renewed focus on the influence of negative life experiences on antisocial behavior. Although a number of studies have generated an impressive array of support for the theory, several avenues remain open for research. In this article, we examine how a specific noxious stimuli, peer…

Test for the determination of 90Sr in soil

International Nuclear Information System (INIS)

1980-01-01

The standardized method is based on the chemical separation (extraction, precipitation, etc.) of 90 Sr from other fission products. After long-term storage for 90 Sr- 90 Y equilibrium the activity of the sample precipitated in the form of Y(COO) 2 is measured. The Sr yield coefficient is determined by 85 Sr tracer or by gravimetry. The test is applicable for the determination of 90 Sr contamination originating from fallout or from other sources in soil, when the concentration of 90 Sr is higher than 0.2-0.4 Bqg -1 (5-10 pCig -1 ). The error of the method is less than +-2% of the amount of the 90 Sr present. (Sz.J.)

China's renewables law

International Nuclear Information System (INIS)

Zhu Li

2005-01-01

The paper discusses China's Renewable Energy Promotion Law which will come into force in January 2006. The law shows China's commitment to renewable energy sources. The target is to raise the country's energy consumption from renewables to 10% by 2020. Data for current capacity, and expected capacity by 2020, are given for wind power, solar power, biomass and hydroelectric power. The financial and technological hurdles which China must overcome are mentioned briefly

Atomic layer epitaxy of Ruddlesden-Popper SrO(SrTiO{sub 3}){sub n} films by means of metalorganic aerosol deposition

Energy Technology Data Exchange (ETDEWEB)

Jungbauer, M.; Hühn, S.; Moshnyaga, V. [Erstes Physikalisches Institut, Universität Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Egoavil, R.; Tan, H.; Verbeeck, J.; Van Tendeloo, G. [EMAT, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)

2014-12-22

We report an atomic layer epitaxial growth of Ruddlesden-Popper (RP) thin films of SrO(SrTiO{sub 3}){sub n} (n = ∞, 2, 3, 4) by means of metalorganic aerosol deposition (MAD). The films are grown on SrTiO{sub 3}(001) substrates by means of a sequential deposition of Sr-O/Ti-O{sub 2} atomic monolayers, monitored in-situ by optical ellipsometry. X-ray diffraction and transmission electron microscopy (TEM) reveal the RP structure with n = 2–4 in accordance with the growth recipe. RP defects, observed by TEM in a good correlation with the in-situ ellipsometry, mainly result from the excess of SrO. Being maximal at the film/substrate interface, the SrO excess rapidly decreases and saturates after 5–6 repetitions of the SrO(SrTiO{sub 3}){sub 4} block at the level of 2.4%. This identifies the SrTiO{sub 3} substrate surface as a source of RP defects under oxidizing conditions within MAD. Advantages and limitations of MAD as a solution-based and vacuum-free chemical deposition route were discussed in comparison with molecular beam epitaxy.

Renewable, ethical? Assessing the energy justice potential of renewable electricity

Directory of Open Access Journals (Sweden)

Aparajita Banerjee

2017-08-01

Full Text Available Energy justice is increasingly being used as a framework to conceptualize the impacts of energy decision making in more holistic ways and to consider the social implications in terms of existing ethical values. Similarly, renewable energy technologies are increasingly being promoted for their environmental and social benefits. However, little work has been done to systematically examine the extent to which, in what ways and in what contexts, renewable energy technologies can contribute to achieving energy justice. This paper assesses the potential of renewable electricity technologies to address energy justice in various global contexts via a systematic review of existing studies analyzed in terms of the principles and dimensions of energy justice. Based on publications including peer reviewed academic literature, books, and in some cases reports by government or international organizations, we assess renewable electricity technologies in both grid integrated and off-grid use contexts. We conduct our investigation through the rubric of the affirmative and prohibitive principles of energy justice and in terms of its temporal, geographic, socio-political, economic, and technological dimensions. Renewable electricity technology development has and continue to have different impacts in different social contexts, and by considering the different impacts explicitly across global contexts, including differences between rural and urban contexts, this paper contributes to identifying and understanding how, in what ways, and in what particular conditions and circumstances renewable electricity technologies may correspond with or work to promote energy justice.

Do state renewable portfolio standards promote in-state renewable generation

International Nuclear Information System (INIS)

Yin, Haitao; Powers, Nicholas

2010-01-01

Several US states have passed renewable portfolio standard (RPS) policies in order to encourage investment in renewable energy technologies. Existing research on their effectiveness has either employed a cross-sectional approach or has ignored heterogeneity among RPS policies. In this paper, we introduce a new measure for the stringency of an RPS that explicitly accounts for some RPS design features that may have a significant impact on the strength of an RPS. We also investigate the impacts of renewable portfolio standards on in-state renewable electricity development using panel data and our new measure of RPS stringency, and compare the results with those when alternative measures are used. Using our new measure, the results suggest that RPS policies have had a significant and positive effect on in-state renewable energy development, a finding which is masked when design differences among RPS policies are ignored. We also find that another important design feature - allowing 'free trade' of REC's - can significantly weaken the impact of an RPS. These results should prove instructive to policy makers, whether considering the development of a federal-level RPS or the development or redesign of a state-level RPS. (author)

Interplay between HIV Entry and Transportin-SR2 Dependency

Directory of Open Access Journals (Sweden)

Gijsbers Rik

2011-01-01

Full Text Available Abstract Background Transportin-SR2 (TRN-SR2, TNPO3, transportin 3 was previously identified as an interaction partner of human immunodeficiency virus type 1 (HIV-1 integrase and functions as a nuclear import factor of HIV-1. A possible role of capsid in transportin-SR2-mediated nuclear import was recently suggested by the findings that a chimeric HIV virus, carrying the murine leukemia virus (MLV capsid and matrix proteins, displayed a transportin-SR2 independent phenotype, and that the HIV-1 N74D capsid mutant proved insensitive to transportin-SR2 knockdown. Results Our present analysis of viral specificity reveals that TRN-SR2 is not used to the same extent by all lentiviruses. The DNA flap does not determine the TRN-SR2 requirement of HIV-1. We corroborate the TRN-SR2 independent phenotype of the chimeric HIV virus carrying the MLV capsid and matrix proteins. We reanalyzed the HIV-1 N74D capsid mutant in cells transiently or stably depleted of transportin-SR2 and confirm that the N74D capsid mutant is independent of TRN-SR2 when pseudotyped with the vesicular stomatitis virus glycoprotein (VSV-G. Remarkably, although somewhat less dependent on TRN-SR2 than wild type virus, the N74D capsid mutant carrying the wild type HIV-1 envelope required TRN-SR2 for efficient replication. By pseudotyping with envelopes that mediate pH-independent viral uptake including HIV-1, measles virus and amphotropic MLV envelopes, we demonstrate that HIV-1 N74D capsid mutant viruses retain partial dependency on TRN-SR2. However, this dependency on TRN-SR2 is lost when the HIV N74D capsid mutant is pseudotyped with envelopes mediating pH-dependent endocytosis, such as the VSV-G and Ebola virus envelopes. Conclusion Here we discover a link between the viral entry of HIV and its interaction with TRN-SR2. Our data confirm the importance of TRN-SR2 in HIV-1 replication and argue for careful interpretation of experiments performed with VSV-G pseudotyped viruses in

Development of materials for use in solid oxid fuel cells anodes using renewable fuels in direct operation

International Nuclear Information System (INIS)

Lima, D.B.P.L. de; Florio, D.Z. de; Bezerra, M.E.O.

2016-01-01

Fuel cells produce electrical current from the electrochemical combustion of a gas or liquid (H2, CH4, C2H5OH, CH3OH, etc.) inserted into the anode cell. An important class of fuel cells is the SOFC (Solid Oxide Cell Fuel). It has a ceramic electrolyte that transports protons (H +) or O-2 ions and operating at high temperatures (500-1000 °C) and mixed conductive electrodes (ionic and electronic) ceramics or cermets. This work aims to develop anodes for fuel cells of solid oxide (SOFC) in order to direct operations with renewable fuels and strategic for the country (such as bioethanol and biogas). In this context, it becomes important to study in relation to the ceramic materials, especially those that must be used in high temperatures. Some types of double perovskites such as Sr2MgMoO6 (or simply SMMO) have been used as anodes in SOFC. In this study were synthesized by the polymeric precursor method, analyzed and characterized different ceramic samples of families SMMO, doped with Nb, this is: Sr2 (MgMo)1-xNbxO6 with 0 ≤ x ≤ 0.2. The materials produced were characterized by various techniques such as, thermal analysis, X-ray diffraction and scanning electron microscopy, and electrical properties determined by dc and ac measurements in a wide range of temperature, frequency and partial pressure of oxygen. The results of this work will contribute to a better understanding of advanced ceramic properties with mixed driving (electronic and ionic) and contribute to the advancement of SOFC technology operating directly with renewable fuels. (author)

44/40Ca and 87Sr/86Sr isotopes as tracers of silicate weathering in small catchments of the Massif Central, France

Science.gov (United States)

Négrel, Philippe; Guerrot, Catherine; Millot, Romain; Petelet-Giraud, Emmanuelle; Bullen, Thomas

2013-04-01

We present calcium stable isotope and strontium radiogenic isotope data for soils and sediments developed on volcanic and igneous rocks forming small catchments in the Massif Central (France). Measurements of 44/40Ca isotope ratios (44/40Ca measured by the double spike method on TIMS and normalized to the value for seawater Ca in delta units) in rocks, sediments and soils from silicate catchments (e.g. granite and basalts) together with 87Sr/86Sr isotope ratios permit an examination of the relationships of these isotope systematics during weathering of silicate rocks. We have analysed the granite, weathered granite (arene) and saprolite, sediment and soil overlying the granite on one hand and the basanite, sediment and soil overlying the basanite on the other. The main bedrock in the volcanic zone (e.g. Allanche catchment) is 11 to 2.5 Ma basanite (nephelinitic to leucitic basalts) having SiO2 between 41-45 wt. %, Na2O + K2O bank have 87Sr/86Sr ratios greater than that of the arene with values increasing in the sediment from the surface down to soil. The 87Sr/86Sr vs. Rb/Sr variation observed in the volcanic area likewise confirms the weathering of low 87Sr/86Sr, low Rb/Sr phases in the bedrock, and there is a linear increase in 87Sr/86Sr and Rb/Sr ratios from those in the sediment up to the values observed in the soils. In the volcanic area, the basanite bedrock has 44/40Ca = -0.94 ± 0.05‰ (n = 7), while the soils and sediments have 44/40Ca of -0.75 to -1.13‰ and -0.79 to -1.01‰, respectively. These results suggest that Ca isotopes are not strongly fractionated during weathering of the basalt. The granite whole-rock has 44/40Ca of -1.29‰, while the soil and sediments have 44/40Ca of -1.93 to -2.07‰ and -1.98 to -2.81‰, respectively, with values decreasing as the Ca content decreases. The 44/40Ca ratios of arene, soil and sediment are similar to or less than that of K- feldspar, reflecting complete loss of the relatively heavy Ca from plagioclase and

Carrier density independent scattering rate in SrTiO3-based electron liquids.

Science.gov (United States)

Mikheev, Evgeny; Raghavan, Santosh; Zhang, Jack Y; Marshall, Patrick B; Kajdos, Adam P; Balents, Leon; Stemmer, Susanne

2016-02-10

We examine the carrier density dependence of the scattering rate in two- and three-dimensional electron liquids in SrTiO3 in the regime where it scales with T(n) (T is the temperature and n ≤ 2) in the cases when it is varied by electrostatic control and chemical doping, respectively. It is shown that the scattering rate is independent of the carrier density. This is contrary to the expectations from Landau Fermi liquid theory, where the scattering rate scales inversely with the Fermi energy (EF). We discuss that the behavior is very similar to systems traditionally identified as non-Fermi liquids (n density-independent scattering rates have been observed. The results indicate that the applicability of Fermi liquid theory should be questioned for a much broader range of correlated materials and point to the need for a unified theory.

Renewable energy

International Nuclear Information System (INIS)

Berghmans, J.

1994-01-01

Renewable energy sources have a small environmental impact and can be easily integrated within existing structures. Moreover, the use of renewable energy sources can contribute to achieve a zero emission of carbon dioxide by 2100, provided an efficient environmental policy during the next 40 years. This includes a correct pricing policy of renewable energy sources with respect to nuclear energy and fossil fuel. The latter energy sources have been favoured in the past. In addition, an open market policy, the restructuring or conversion of existing international energy institutes, and international treaties for the protection of the natural environment are needed in view of achieving the zero carbon dioxide emission objective. (A.S.)

2015 Renewable Energy Data Book

Energy Technology Data Exchange (ETDEWEB)

Beiter, Philipp [National Renewable Energy Lab. (NREL), Golden, CO (United States); Tian, Tian [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-11-01

The Renewable Energy Data Book for 2015 provides facts and figures on energy and electricity use, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, marine and hydrokinetic power, hydrogen, renewable fuels, and clean energy investment.

2015 Renewable Energy Data Book

Energy Technology Data Exchange (ETDEWEB)

Beiter, Philipp; Tian, Tian

2016-11-01

The 2015 Renewable Energy Data Book provides facts and figures on energy and electricity use, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, marine and hydrokinetic power, hydrogen, renewable fuels, and clean energy investment.

2014 Renewable Energy Data Book

Energy Technology Data Exchange (ETDEWEB)

Beiter, Philipp

2015-11-01

The Renewable Energy Data Book for 2014 provides facts and figures on energy and electricity use, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, marine and hydrokinetic power, hydrogen, renewable fuels, and clean energy investment.

2016 Renewable Energy Data Book

Energy Technology Data Exchange (ETDEWEB)

2017-12-29

The 2016 Renewable Energy Data Book provides facts and figures on energy and electricity use, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, marine and hydrokinetic power, hydrogen, renewable fuels, and clean energy investment.

Public opinion and communicative action around renewable energy projects

Science.gov (United States)

Fast, Stewart

This thesis investigates how rural communities negotiate the development of renewable energy projects. Public and local community acceptance of these new technologies in rural areas around the world is uncertain and spatially uneven and represents an area of emerging public policy interest and one where scholarly theory is rapidly developing. This thesis uses Habermasian concepts of public sphere, communicative action and deliberative democracy, as well as the concept of "wicked problems" from the planning studies literature combined with geographical concepts of place and scale to advance theoretical and empirical understanding of how public opinion on renewable energy technologies is formed in place. It documents energy use patterns, attitudes and socio-political relations at a time when considerable state and business efforts are directed at the construction of solar, wind, biomass and small-hydro technologies in rural regions. These concepts and theories are applied in a case study of rural communities in the Eastern Ontario Highlands, an impoverished area undergoing rapid restructuring driven by centralization of services and amenity migration but with abundant natural resources in form of forests, numerous waterways and open space which have attracted a broad range of new energy developments. Overall high levels of support for alternative energy development particularly for solar power were found, albeit for reasons of local energy security and not for reasons of preventing climate change. There was some evidence that seasonal residents are less supportive of hydro and biomass projects than permanent residents possibly reflecting broader trends in rural economies away from productive uses of land to consumptive appreciation of rural landscapes. The thesis suggests that collective action to advance energy projects in the case study area require agreement along three world-claims (truth, rightness and truthfulness) and that communication leading to discourse

Renewables 2017 Global Status Report

International Nuclear Information System (INIS)

Sawin, Janet L.; Sverrisson, Freyr; Seyboth, Kristin; Adib, Rana; Murdock, Hannah E.; Lins, Christine; Edwards, Isobel; Hullin, Martin; Nguyen, Linh H.; Prillianto, Satrio S.; Satzinger, Katharina; Appavou, Fabiani; Brown, Adam; Chernyakhovskiy, Ilya; Logan, Jeffrey; Milligan, Michael; Zinaman, Owen; Epp, Baerbel; Huber, Lon; Lyons, Lorcan; Nowak, Thomas; Otte, Pia; Skeen, Jonathan; Sovacool, Benjamin; Witkamp, Bert; Musolino, Evan; Brown, Adam; Williamson, Laura E.; Ashworth, Lewis; Mastny, Lisa

2017-01-01

Renewable energy technologies increase their hold across developing and emerging economies throughout the year The year 2016 saw several developments and ongoing trends that all have a bearing on renewable energy, including the continuation of comparatively low global fossil fuel prices; dramatic price declines of several renewable energy technologies; and a continued increase in attention to energy storage. For the third consecutive year, global energy-related carbon dioxide emissions from fossil fuels and industry were nearly flat in 2016, due largely to declining coal use worldwide but also due to improvements in energy efficiency and to increasing use of renewable energy. As of 2015, renewable energy provided an estimated 19.3% of global final energy consumption, and growth in capacity and production continued in 2016. The power sector experienced the greatest increases in renewable energy capacity in 2016, whereas the growth of renewables in the heating and cooling and transport sectors was comparatively slow. Most new renewable energy capacity is installed in developing countries, and largely in China, the single largest developer of renewable power and heat over the past eight years. In 2016, renewable energy spread to a growing number of developing and emerging economies, some of which have become important markets. For the more than 1 billion people without access to electricity, distributed renewable energy projects, especially those in rural areas far from the centralised grid, offer important and often cost-effective options to provide such access. The renewable energy sector employed 9.8 million people in 2016, an increase of 1.1% over 2015. By technology, solar PV and biofuels provided the largest numbers of jobs. Employment shifted further towards Asia, which accounted for 62% of all renewable energy jobs (not including large-scale hydropower), led by China. The development of community renewable energy projects continued in 2016, but the pace of

In situ Sr/Sr investigation of igneous apatites and carbonates using laser-ablation MC-ICP-MS

DEFF Research Database (Denmark)

Bizzarro, Martin; Simonetti, A.; Stevenson, R.K.

2003-01-01

In situ Sr isotopic compositions of coexisting apatite and carbonate for carbonatites from the Sarfartoq alkaline complex, Greenland, have been determined by laser-ablation multicollector inductively coupled plasma mass spectrometry. This study is the first to examine the extent of Sr isotopic ho...

Hybrid HF-DFT comparative study of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties

Energy Technology Data Exchange (ETDEWEB)

Evarestov, R.A.; Bandura, A.V.; Alexandrov, V.E. [Department of Quantum Chemistry, St. Petersburg State University, 26 Universitetskii Prospekt, Stary Petergof, 198504 St. Petersburg (Russian Federation)

2006-10-15

Hybrid HF-DFT LCAO simulations of SrZrO{sub 3} and SrTiO{sub 3}(001) surface properties are performed in a single-slab model framework. The SrZrO{sub 3}(001) surface was studied by an ab initio method for the first time. Three slab models with different surface terminations including up to 8 atomic planes were used for calculation of the various surface characteristics (surface energies, atomic charges, density of electronic states). The dependence of the results on the chosen model and on the kind of d-element is analyzed. The dissimilarity in the surface oxygen atom contributions to the total density of states of two crystals is attributed to the more ionic nature of Zr-O bonds compared to Ti-O bonds. It is found that in the case of SrZrO{sub 3} the electronic density is biased towards the SrO-terminated surface and this surface should be more basic in nature than the SrO surface of SrTiO{sub 3} crystal. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Determination of the shape factor of {sup 90}Sr by means of the cutoff energy yield method

Energy Technology Data Exchange (ETDEWEB)

Grau Carles, A. [Instituto de Matematicas y Fisica Fundamental (CSIC), Dcho. 211, C/Serrano 113b, 28006 Madrid (Spain)], E-mail: agrau@imaff.cfmac.csic.es; Kossert, K. [Physikalisch-Technische Bundesanstalt, Department 6.1, Bundesallee 100, D-38116 Braunschweig (Germany); Grau Malonda, A. [CIEMAT, Departamento de Proyectos Estrategicos, Avda. Complutense 22, 28040 Madrid (Spain)

2008-06-15

Usually, Kurie plots are used to analyze beta-spectra shape-factor functions measured by means of semiconductor and magnetic spectrometers. A drawback of these techniques is the occurrence of self-absorption within the samples through which the emission spectrum is altered. In liquid-scintillation samples self-absorption does not occur, but the poor energy resolution makes the analysis of the spectra difficult. To overcome this problem, two resolution-invariant observables are used for determining the shape-factor function of {sup 90}Sr: (1) the maximum point energy and (2) the cutoff energy yield. The measured shape-factor function of {sup 90}Sr agrees with the one which is predicted by theory for the first-forbidden unique transition.

Theoretical investigation on thermoelectric properties of (Ca,Sr,Ba)Fe2(As/Bi)2 compounds under temperature

Science.gov (United States)

Jayalakshmi, D. S.; Sundareswari, M.; Viswanathan, E.; Das, Abhijeet

2018-04-01

The electrical conductivity, resistivity and Seebeck coefficient, Pauli magnetic susceptibility and power factor are computed under temperature (100 K - 800 K) in steps of 100 K for the theoretically designed compounds namely (Ca,Sr,Ba)Fe2Bi2 and their parent compounds namely (Ca,Sr,Ba)Fe2As2 by using Boltzmann transport theory interfaced to the Wien2k program. The Bulk modulus, electron phonon coupling constant, thermoelectric figure of merit (ZT) and transition temperature are calculated for the optimized anti ferromagnetic phase of the proposed compounds. The results are discussed for the novel compounds in view of their superconductivity existence and compared with their parent unconventional superconducting compounds.

Save with Renewable Energy: A Technical Bulletin for Federal Renewable Energy Champions

Energy Technology Data Exchange (ETDEWEB)

2003-11-01

This eight-page publication, prepared in 2003 for the U.S. Department of Energy's Federal Energy Management Program by the DOE National Renewable Energy Laboratory, is an updated version of the former Save with Solar and Wind bulletin. Save with Renewable Energy provides up-to-date information about the progress that the government is making in achieving federal goals for renewable energy use; agencies have achieved about 60% of the current goal for 2005 of 1384 gigawatt-hours from renewable energy systems. This publication also describes current and planned federal projects featuring wind, solar, and geothermal systems in several different states.

Effect of Varying Pnictogen Elements (Pn=N, P, As, Sb, Bi) on the Optoelectronic Properties of SrZn2Pn2

Science.gov (United States)

Murtaza, G.; Yousaf, N.; Laref, A.; Yaseen, M.

2018-03-01

Pnictogen-based Zintl compounds have fascinating properties. Nowadays these compounds have gained exceptional interest in thermoelectric and optoelectronic fields. Therefore, in this work the structural, electronic and optical properties of SrZn2Pn2 (Pn=N, P, As, Sb, Bi) compounds were studied using state-of-the-art density functional theory. The optimised lattice parameters (ɑ, c, c/ɑ and bond lengths) are consistent with the experimental results. The bulk moduli and c/a showed a decrease when changing the Pnictogen (Pn) anion from N to Bi in SrZn2Pn2 (Pn=N, P, As, Sb, Bi). The modified Becke-Johnson potential is used for band structure calculations. All compounds show semiconducting behaviour except SrZn2Bi2, which is metallic. Pn-p, Zn-d and Sr-d play an important role in defining the electronic structure of the compounds. The optical conductivity and absorption coefficient strength are high in visible and ultraviolet regions. These band structures and optical properties clearly show that SrZn2Pn2 compounds are potential candidates in the fields of optoelectronic and photonic devices.

Determination of the electrostatic potential distribution in Pt/Fe:SrTiO₃/Nb:SrTiO₃ thin-film structures by electron holography.

Science.gov (United States)

Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E; Waser, Rainer

2014-11-10

We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

Using noble gases and 87Sr/86Sr to constrain heat sources and fluid evolution at the Los Azufres Geothermal Field, Mexico

Science.gov (United States)

Wen, T.; Pinti, D. L.; Castro, M. C.; Lopez Hernandez, A.; Hall, C. M.; Shouakar-Stash, O.; Sandoval-Medina, F.

2017-12-01

Geothermal wells and hot springs were sampled for noble gases' volume fraction and isotopic measurements and 87Sr/86Sr in the Los Azufres Geothermal Field (LAGF), Mexico, to understand the evolution of fluid circulation following three decades of exploitation and re-injection of used brines. The LAGF, divided into the Southern Production Zone (SPZ) and the Northern Production Zone (NPZ), is hosted in a Miocene to Pliocene andesitic volcanic complex covered by Quaternary rhyolitic-dacitic units. Air contamination corrected 3He/4He ratios (Rc) normalized to the atmospheric ratio (Ra=1.384 x 10-6), show a median value of 6.58 indicating a dominant mantle helium component. Contributions of crustal helium up to 53% and 18% are observed in NPZ and SPZ, respectively. Observations based on Rc/Ra and 87Sr/86Sr ratios points to the mixing of three magmatic sources supplying mantle helium to the LAGF: (1) a pure mantle He (Rc/Ra = 8) and Sr (87Sr/86Sr = 0.7035) source; (2) a pure mantle helium (Rc/Ra = 8) with some radiogenic Sr (87Sr/86Sr = 0.7049) source possibly resulting from Quaternary rhyolitic volcanism; and (3) a fossil mantle He component (Rc/Ra = 3.8) with some radiogenic Sr (87Sr/86Sr = 0.7038), corresponding possibly to the Miocene andesite reservoir. Intrusions within the last 50 kyrs from sources (1) and (2) are likely responsible for the addition of mantle volatiles and heat to the hydrothermal system of Los Azufres. He and Ar isotopes indicate that heat flow is transported by both convection and conduction. Atmospheric noble gas elemental ratios suggest that geothermal wells located closer to the western re-injection zone are beginning to be dominated by re-injection of used brines (injectate). The area affected by boiling in LAGF has further extended to the north and west since the last noble gas sampling campaign in 2009.

Thermodynamic modeling of the Sr-Co-Fe-O system

DEFF Research Database (Denmark)

Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

2016-01-01

This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...... using the CALPHAD approach and was further extrapolated to that of Sr-Co-Fe-O. The thermodynamic database of Sr-Co-Fe-O established in this work allows for calculating phase diagrams, thermodynamic properties, cation distribution and defect chemistry properties, and therefore enables material...

Factors affecting 90Sr uptake from the ration

International Nuclear Information System (INIS)

Knizhnikov, V.A.; Marej, A.N.; Borisov, B.K.; Petukhova, Eh.V.

1980-01-01

The dependence of 90 Sr uptake in the human organism on nutrition peculiarities is shown. Strontium-90 polluting vegetable products due to particle sorption from the air is less available for the uptake than 90 Sr resorbed from the soil with vegetation. Therefore, this nuclide is uptaken more completely from milk which containes 90 Sr in a soluble form than from grain and bakery products which are polluted by 90 Sr largely by air

Decoupling of unpolluted temperate forests from rock nutrient sources revealed by natural 87Sr/86Sr and 84Sr tracer addition

Science.gov (United States)

Kennedy, Martin J.; Hedin, Lars O.; Derry, Louis A.

2002-01-01

An experimental tracer addition of 84Sr to an unpolluted temperate forest site in southern Chile, as well as the natural variation of 87Sr/86Sr within plants and soils, indicates that mechanisms in shallow soil organic horizons are of key importance for retaining and recycling atmospheric cation inputs at scales of decades or less. The dominant tree species Nothofagus nitida feeds nearly exclusively (>90%) on cations of atmospheric origin, despite strong variations in tree size and location in the forest landscape. Our results illustrate that (i) unpolluted temperate forests can become nutritionally decoupled from deeper weathering processes, virtually functioning as atmospherically fed ecosystems, and (ii) base cation turnover times are considerably more rapid than previously recognized in the plant available pool of soil. These results challenge the prevalent paradigm that plants largely feed on rock-derived cations and have important implications for understanding sensitivity of forests to air pollution. PMID:12119394

The renewable chemicals industry

DEFF Research Database (Denmark)

Christensen, Claus H.; Rass-Hansen, J.; Marsden, Charlotte Clare

2008-01-01

per kilogram of desired product to illustrate in which processes the use of renewable resources lead to the most substantial reduction of CO2 emissions. The steps towards a renewable chemicals industry will most likely involve intimate integration of biocatalytic and conventional catalytic processes......The possibilities for establishing a renewable chemicals industry featuring renewable resources as the dominant feedstock rather than fossil resources are discussed in this Concept. Such use of biomass can potentially be interesting from both an economical and ecological perspective. Simple...

New renewable energy sources

International Nuclear Information System (INIS)

2001-06-01

This publication presents a review of the technological, economical and market status in the field of new renewable energy sources. It also deals briefly with the present use of energy, external conditions for new renewable energy sources and prospects for these energy sources in a future energy system. The renewable energy sources treated here are ''new'' in the sense that hydroelectric energy technology is excluded, being fully developed commercially. This publication updates a previous version, which was published in 1996. The main sections are: (1) Introduction, (2) Solar energy, (3) Bio energy, (4) Wind power, (5) Energy from the sea, (6) Hydrogen, (7) Other new renewable energy technologies and (8) New renewable s in the energy system of the future

Renewables in the Midwest

International Nuclear Information System (INIS)

Wager, J.S.

1994-01-01

Over the past three years, the Union of Concerned Scientists (UCS) has evaluated the potential for using renewable energy for electricity in the Midwest, and has been carrying out a multifaceted effort to expand the use of renewables in the region. The UCS study presents a strategy for developing renewable-electric technologies and resources in 12 midwestern states. UCS analysts used a geographic information system (GIS) to create data-bases of renewable resources, land uses, vegetation cover, terrain elevation and locations of utility transmission lines, and to analyze and present information on a .6 mi x .6 mi (1 km x 1 km) grid scale. In addition, UCS developed a model to calculate the net employment impact of renewable versus conventional electricity technologies on a state-by-state basis. In evaluating the costs and benefits of renewable energy sources, UCS analysts explored a cost assessment that accounted for the impact of pollution from fossil fuels on energy resource cost. Researchers also considered the risks associated with fuel-price volatility, environmental regulation, construction lead times and other uncertainties. Finally, UCS researchers suggested steps to remove the institutional, regulatory and legislative barriers that inhibit renewable energy development, and proposed policies to expand the use of the region's renewable resources. The UCS analysis showed that wind is currently the least expensive renewable resource. UCS also found numerous opportunities to expand biomass-electric generation in the near term, such as converting small coal-fired power plants to wood fuel, making greater use of logging residues and co-firing a small percentage of biomass with fossil fuel at large power plants

Size exclusion chromatography for semipreparative scale separation of Au38(SR)24 and Au40(SR)24 and larger clusters.

Science.gov (United States)

Knoppe, Stefan; Boudon, Julien; Dolamic, Igor; Dass, Amala; Bürgi, Thomas

2011-07-01

Size exclusion chromatography (SEC) on a semipreparative scale (10 mg and more) was used to size-select ultrasmall gold nanoclusters (<2 nm) from polydisperse mixtures. In particular, the ubiquitous byproducts of the etching process toward Au(38)(SR)(24) (SR, thiolate) clusters were separated and gained in high monodispersity (based on mass spectrometry). The isolated fractions were characterized by UV-vis spectroscopy, MALDI mass spectrometry, HPLC, and electron microscopy. Most notably, the separation of Au(38)(SR)(24) and Au(40)(SR)(24) clusters is demonstrated.

Thermodynamic modeling of the Sr-Co-Fe-O system

DEFF Research Database (Denmark)

Zhang, Wei Wei; Povoden-Karadeniz, Erwin; Chen, Ming

2016-01-01

This paper reviews and assesses phase equilibria and thermodynamic properties of phases in the Sr-Co-Fe-O system, with a focus on oxides, especially the SrCo1 - xFexO3 - δ perovskite. In our work, the SrCo1 - xFexO3 - δ perovskite was modeled with a three-sublattice model, where the three...... sublattices correspond to the A, B and oxygen sites in an ABO3 perovskite, respectively. A number of other important ternary oxide phases in Sr-Co-O and Sr-Co-Fe-O were also considered. Available thermodynamic and phase diagram data were carefully assessed. A thermodynamic description of Sr-Co-O was derived...

Temperature effect on the retention of U(VI) by SrTiO{sub 3}; Effet de la temperature sur la retention de U(VI) par SrTiO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Garcia Rosales, G

2007-11-15

The purpose of this research was the study of the interaction mechanisms between U(VI) ions and SrTiO{sub 3} surfaces versus pH and temperature: 25, 50, 75 and 90 C. Firstly, a physicochemical characterization was realized (DRX, MEB, FTIR) and the surface site density was determined. The potentiometric titration data were simulated, for each temperature, using the constant capacitance model and taking into account bath protonation of the {identical_to}Sr-OH surface sites and deprotonation of the {identical_to}Ti-OH ones (one pK{sub a} model). Both enthalpy and entropy changes, corresponding to the surface acid-base reactions, were evaluated using the van't Hoff relation. U(VI) was sorbed onto SrTiO{sub 3} powder in the pH range 0.5-5.0 with an U(VI) initial concentration 1.10{sup -4} M. By TRLIFS two U(VI) complexes were detected associated with two lifetime values (60 {+-} 5 and 12 {+-} 2 {mu}s at 25 C). The sorption edges were simulated using FITEQL 4.0 software. The surface complexation constants of the system SrTiO{sub 3}/U(VI) between 25 and 90 C temperature range were thus obtained with the constant capacitance model considering two reactive surface sites. It reveals that two types of surface complex, namely [({identical_to}SrOH)({identical_to}TiOH)UO{sub 2}]{sup 2+} and [({identical_to}TiOH)({identical_to}TiO)UO{sup 2+}]{sup 2+}, are needed to properly describe the experimental observations. By application of the van't Hoff equation, Delta{sub R}S{sup 0} and Delta{sub R}H{sup 0} were obtained, which indicated an endothermic sorption process. Finally, an energy transfer study was realised by TRLIFS. The energy transfer between Tb{sup 3+} and Eu{sup 3+} ions sorbed onto SrTiO{sub 3} powders were investigated. The results showed that the energy transfer between Tb{sup 3+} and Eu{sup 3+} is a non-radiative process and follows a dipole-dipole type interaction. A formalism based on the Dexter and the Inokuti-Hirayama theories was used to calculate the

Applying Classical Ethical Theories to Ethical Decision Making in Public Relations: Perrier's Product Recall.

Science.gov (United States)

Pratt, Cornelius B.

1994-01-01

Links ethical theories to the management of the product recall of the Perrier Group of America. Argues for a nonsituational theory-based eclectic approach to ethics in public relations to enable public relations practitioners, as strategic communication managers, to respond effectively to potentially unethical organizational actions. (SR)

The 87Sr/86Sr aquatic isoscape of the Danube catchment from the source to the mouth as tool for studying fish migrations

Science.gov (United States)

Zitek, Andreas; Tchaikovsky, Anastassiya; Irrgeher, Johanna; Waidbacher, Herwig; Prohaska, Thomas

2014-05-01

Isoscapes - spatially distributed isotope patterns across landscapes - are increasingly used as important basis for ecological studies. The natural variation of the isotopic abundances in a studied area bears the potential to be used as natural tracer for studying e.g. migrations of animals or prey-predator relations. The 87Sr/86Sr ratio is one important tracer, since it is known to provide a direct relation of biological samples to geologically distinct regions, as Sr isotopes are incorporated into living tissues as a proxy for calcium and taken up from the environment without any significant fractionation. Although until now the focus has been mainly set on terrestrial systems, maps for aquatic systems are increasingly being established. Here we present the first 87Sr/86Sr aquatic isoscape of the Danube catchment, the second largest river catchment in Europe, from near its source starting at river km 2581 in Germany down to its mouth to river km 107 in Romania. The total length of the river Danube is 2780 km draining a catchment area 801 463 km2 (10 % of the European continent). The major purpose of this study was to assess the potential of the 87Sr/86Sr isotope ratio to be used as tool for studying fish migrations at different scales in the entire Danube catchment. Within the Joint Danube Research 3 (JDS 3), the biggest scientific multi-disciplinary river expedition of the World in 2013 aiming at the assessment of the ecological status and degree of human alterations along the river Danube, water samples were taken at 68 pre-defined sites along the course of the river Danube including the major tributaries as a basis to create the so called 'Isoscape of the Danube catchment'. The determination of 87Sr/86Sr isotope ratio in river water was performed by multicollector-sector field-inductively coupled plasma-mass spectrometry (MC-SF-ICP-MS). The JDS 3 data were combined with existing data from prior studies conducted within the Austrian part of the Danube catchment

Rapid determination of 90Sr in seawater

International Nuclear Information System (INIS)

Pavlotskaya, F.I.; Moskin, A.I.

1994-01-01

A method for determining 90 Sr in seawater that is based on direct isolation and radiochemical purification of daughter 90 Y is proposed. The analysis time is 6-8 h. The chemical yield of the Y-carrier during the 90 Sr determination from 35 liters of seawater varies in the range 37-69%. The analysis uncertainty is 90 Sr from seawater and subsequent isolation of 90 Y

PRODUCTION OF PLANTARCIN BY LACTOBACILLUS PLANTARUM SR18

Directory of Open Access Journals (Sweden)

Wagih El-Shouny

2012-06-01

Full Text Available Out of 86 lactobacilli previously screened in our laboratory, Lactobacillus plantarum SR18 isolated from yoghurt revealed the largest detected inhibition zone against the selected indicator Streptococcus salivarius 5. The obtained electrophoretic patterns revealed that L. plantarum SR18 was free from plasmids. Exposure of 6 h growing L. plantarum culture to T-8M, 3B ultraviolet B lamp (8w, 220v & 312 nm for 2 h and subsequent growth for further 24 h resulted in an increase of cell-bound bacteriocin titer reached 2 fold at 12 h. Whereas bacteriocin secreted in the culture filtrate was not affected by UV irradiation. Plantarcin SR18 production was maximal (12800 AU/ml between 12 and 18 h by incubation of the culture at 37°C and pH 5-7 in candle jar (CO2. The bacteriocin bound to the cells and that secreted into the culture filtrate of L. plantarum SR18 were precipitated by 75% ammomium sulphate, dialysed and further purified by Gel filtration on Sephadex G-100. The specific activities (AU/mg protein were increased by a factor of about 5.3 and 2.35 for plantarcins purified from proteins bound to the cell of L. plantarum SR18 (plantarcin SR18 a and that secreted into the culture filtrate (plantarcin SR18 b, respectively. Gel filtration of plantarcin SR18a resulted in moderate antibacterial activity (3200 AU/ml and very high activity (25600 AU/ml of plantarcin SR18b.

90Sr and 89Sr in seawater off Japan as a consequence of the Fukushima Dai-ichi nuclear accident

Directory of Open Access Journals (Sweden)

N. Casacuberta

2013-06-01

Full Text Available The impact of the earthquake and tsunami on the east coast of Japan on 11 March 2011 caused a loss of power at the Fukushima Dai-ichi nuclear power plant (NPP that resulted in one of the most important releases of artificial radioactivity into the environment. Although several works were devoted to evaluating the atmospheric dispersion of radionuclides, the impact of the discharges to the ocean has been less investigated. Here we evaluate the distribution of Fukushima-derived 90Sr (n = 57 and 89Sr (n = 19 throughout waters 30–600 km offshore in June 2011. Concentrations of 90Sr and 89Sr in both surface waters and shallow profiles ranged from 0.8 ± 0.2 to 85 ± 3 Bq m−3 and from 19 ± 6 to 265 ± 74 Bq m−3, respectively. Because of its short half-life, all measured 89Sr was due to the accident, while the 90Sr concentrations can be compared to the background levels in the Pacific Ocean of about 1.2 Bq m−3. Fukushima-derived radiostrontium was mainly detected north of Kuroshio Current, as this was acting as a southern boundary for transport. The highest activities were associated with near-shore eddies, and larger inventories were found in the closest stations to Fukushima NPP. The data evidence a major influence of direct liquid discharges of radiostrontium compared to the atmospheric deposition. Existing 137Cs data reported from the same samples allowed us to establish a 90Sr / 137Cs ratio of 0.0256 ± 0.0006 in seawater off Fukushima, being significantly different than that of the global atmospheric fallout (i.e., 0.63 and may be used in future studies to track waters coming from the east coast of Japan. Liquid discharges of 90Sr to the ocean were estimated, resulting in an inventory of 53 ± 1 TBq of 90Sr in the inshore study area in June 2011 and total releases of 90Sr ranging from 90 to 900 TBq, depending upon the reported estimates of 137Cs releases that are considered.

Crystal structures of KM(AsF6)3 (M2+ = Mg, Co, Mn, Zn), KCu(SbF6)3 and [Co(HF)2]Sr[Sr(HF)]2-[Sr(HF)2]2[AsF6]12

International Nuclear Information System (INIS)

Mazej, Zoran; Goreshnik, Evgeny

2015-01-01

The KM(AsF 6 ) 3 (M 2+ = Mg, Co, Mn, Zn) and KCu(SbF 6 ) 3 compounds crystallize isotypically to previously known KNi(AsF 6 ) 3 . The main features of the structure of these compounds are rings of MF 6 octahedra sharing apexes with AsF 6 octahedra connected into infinite tri-dimensional frameworks. In this arrangement cavities are formed where K + cations are placed. Single crystals of CoSr 5 (AsF 6 ) 12 .8HF were obtained as one of the products after the crystallization of 3KF/CoF 2 /SrF 2 mixture in the presence of AsF 5 in anhydrous HF. The CoSr 5 (AsF 6 ) 12 .8HF is monoclinic, C/2c (No.15), with a = 26.773(5) Aa, b = 10.087(2) Aa, c = 21.141(5) Aa, β = 93.296(13) circle , V = 5699.9(19) Aa 3 at 200 K, and Z = 4. There are three crystallographically non-equivalent Sr 2+ cations in the crystal structure of CoSr 5 (AsF 6 ) 12 .8HF. The Sr1 is coordinated by ten fluorine atoms from eight different [AsF 6 ]- anions, meanwhile Sr2 and Sr3 are bound to nine fluorine atoms provided by one HF and eight AsF 6 units or by two HF and six AsF 6 units, respectively. The Co 2+ is coordinated distorted-octahedrally by six fluorine atoms from two HF molecules and four different AsF 6 units. All those moieties in the crystal structure of [Co(HF) 2 ]Sr[Sr(HF)] 2 [Sr(HF) 2 ] 2 [AsF 6 ] 12 are connected into tridimensional framework. The CoSr 5 (AsF 6 ) 12 .8HF is a unique example of compound where HF molecules are directly bound via fluorine atoms to two different metal centres.

Geographical distribution of 90Sr contamination in Poland

International Nuclear Information System (INIS)

Gaca, P.; Mietelski, J.W.; Skwarzec, B.

2006-01-01

The paper presents results on determination of 90 Sr in bilberry and cowberry leaves (Vaccinium myrtillus and Vaccinium vitis-idaea) and the use of these plants as bio-monitors of radiostrontium contamination in Poland. Radiostrontium was determined by mean of liquid scintillation spectrometry preceded by radiochemical separation using Sr-resin and 85 Sr tracer. The approximate map of 90 Sr contamination of Poland is presented. The activity ratio between 90 Sr and obtained earlier data for 137 Cs in the same samples is discussed. The enhancement of radiostrontium content observed in northeastern Poland seems to be the trace of hot-particles fallout from initial Chernobyl cloud, which passed over Polish territory toward Scandinavia. (orig.)

Renewable Energy Certificate Program

Energy Technology Data Exchange (ETDEWEB)

Gwendolyn S. Andersen

2012-07-17

This project was primarily to develop and implement a curriculum which will train undergraduate and graduate students at the University seeking a degree as well as training for enrollees in a special certification program to prepare individuals to be employed in a broad range of occupations in the field of renewable energy and energy conservation. Curriculum development was by teams of Saint Francis University Faculty in the Business Administration and Science Departments and industry experts. Students seeking undergraduate and graduate degrees are able to enroll in courses offered within these departments which will combine theory and hands-on training in the various elements of wind power development. For example, the business department curriculum areas include economic modeling, finance, contracting, etc. The science areas include meteorology, energy conversion and projection, species identification, habitat protection, field data collection and analysis, etc.

Nuclear plant license renewal

International Nuclear Information System (INIS)

Gazda, P.A.; Bhatt, P.C.

1991-01-01

During the next 10 years, nuclear plant license renewal is expected to become a significant issue. Recent Electric Power Research Institute (EPRI) studies have shown license renewal to be technically and economically feasible. Filing an application for license renewal with the Nuclear Regulatory Commission (NRC) entails verifying that the systems, structures, and components essential for safety will continue to perform their safety functions throughout the license renewal period. This paper discusses the current proposed requirements for this verification and the current industry knowledge regarding age-related degradation of structures. Elements of a license renewal program incorporating NRC requirements and industry knowledge including a schedule are presented. Degradation mechanisms for structural components, their significance to nuclear plant structures, and industry-suggested age-related degradation management options are also reviewed

Renewal-anomalous-heterogeneous files

International Nuclear Information System (INIS)

Flomenbom, Ophir

2010-01-01

Renewal-anomalous-heterogeneous files are solved. A simple file is made of Brownian hard spheres that diffuse stochastically in an effective 1D channel. Generally, Brownian files are heterogeneous: the spheres' diffusion coefficients are distributed and the initial spheres' density is non-uniform. In renewal-anomalous files, the distribution of waiting times for individual jumps is not exponential as in Brownian files, yet obeys: ψ α (t)∼t -1-α , 0 2 >, obeys, 2 >∼ 2 > nrml α , where 2 > nrml is the MSD in the corresponding Brownian file. This scaling is an outcome of an exact relation (derived here) connecting probability density functions of Brownian files and renewal-anomalous files. It is also shown that non-renewal-anomalous files are slower than the corresponding renewal ones.

Epitaxial phase diagrams of SrTiO3, CaTiO3, and SrHfO3: Computational investigation including the role of antiferrodistortive and A -site displacement modes

Science.gov (United States)

Angsten, Thomas; Asta, Mark

2018-04-01

Ground-state epitaxial phase diagrams are calculated by density functional theory (DFT) for SrTiO3, CaTiO3, and SrHfO3 perovskite-based compounds, accounting for the effects of antiferrodistortive and A -site displacement modes. Biaxial strain states corresponding to epitaxial growth of (001)-oriented films are considered, with misfit strains ranging between -4 % and 4%. Ground-state structures are determined using a computational procedure in which input structures for DFT optimizations are identified as local minima in expansions of the total energy with respect to strain and soft-mode degrees of freedom. Comparison to results of previous DFT studies demonstrates the effectiveness of the computational approach in predicting ground-state phases. The calculated results show that antiferrodistortive octahedral rotations and associated A -site displacement modes act to suppress polarization and reduce the epitaxial strain energy. A projection of calculated atomic displacements in the ground-state epitaxial structures onto soft-mode eigenvectors shows that three ferroelectric and six antiferrodistortive displacement modes are dominant at all misfit strains considered, with the relative contributions from each varying systematically with the strain. Additional A -site displacement modes contribute to the atomic displacements in CaTiO3 and SrHfO3, which serve to optimize the coordination of the undersized A -site cation.

Contrasting pressure effects in Sr2VFeAsO3 and Sr2ScFePO3

International Nuclear Information System (INIS)

Kotegawa, Hisashi; Kawazoe, Takayuki; Tou, Hideki; Murata, Keizo; Ogino, Hiraku; Kishio, Kohji; Shimoyama, Jun-ichi

2009-01-01

We report the resistivity measurements under pressure of two Fe-based superconductors with a thick perovskite oxide layer, Sr 2 VFeAsO 3 and Sr 2 ScFePO 3 . The superconducting transition temperature T c of Sr 2 VFeAsO 3 markedly increases with increasing pressure. Its onset value, which was T c onset =36.4 K at ambient pressure, increases to T c onset =46.0 K at ∼4 GPa, ensuring the potential of the '21113' system as a high-T c material. However, the superconductivity of Sr 2 ScFePO 3 is strongly suppressed under pressure. The T c onset of ∼16 K decreases to ∼5 K at ∼4 GPa, and the zero-resistance state is almost lost. We discuss the factor that induces this contrasting pressure effect. (author)

Prospects for renewable energy in South Africa. Mobilizing the private sector

Energy Technology Data Exchange (ETDEWEB)

Pegels, Anna

2009-07-01

The challenge of transforming entire economies is enormous, especially if a country is as fossil- fuel-based and emission-intensive as South Africa. However, as it is already facing climate change impacts in an increasingly carbon-constrained world, South Africa must drastically reduce its greenhouse gas emission intensity soon. The South African electricity sector is a vital part of the economy and at the same time contributes most to the emission problem. Transforming this sector is therefore urgently needed, but will be difficult. First steps have been taken to enhance energy efficiency and promote renewable energy, but they have failed to have any large-scale effects. The two major barriers to investments in renewable energy technologies are based in the South African energy innovation system and its inherent power structures and in the economics of renewable energy technologies. The innovation system is dominated by the state-owned Eskom (electricity) and Sasol (fuel) enterprises. Both companies have their core competencies in fossil fuel technologies. Capacity in renewable energy is lacking at every stage of the technology cycle, from research and development to installation and maintenance. The obstacles inherent in the economics of renewable energy technologies are cost and risk, two of the main factors in investment planning. As most technologies are in early stages of development, they have not yet realized their full cost degression potential and continue to entail a higher risk than established technologies. To overcome these barriers, the South African government has introduced several renewable energy support measures, such as a renewable energy feed-in tariff (REFIT). While a promising scheme in theory, the South African REFIT has a crucial flaw: Eskom is the monopsonistic buyer of electricity produced from renewable energy and is responsible for distributing it to consumers. However, Eskom is not obliged to buy that electricity. This runs counter to

Rb-Sr ages and initial 87Sr/86Sr ratios of late paleozoic granitic rocks from northern Chile

International Nuclear Information System (INIS)

Shibata, Ken; Ishihara, Shunso; Ulriksen, C.E.

1984-01-01

Rb-Sr whole-rock isochron ages were determined on three suites of so-called Paleozoic granitic rocks from northern coastal Chile. The granitic rocks from the Valparaiso and Ci Funcho areas are dated as 296.3 +- 5.4 Ma and 262.2 +- 4.6 Ma, respectively, which are in accord with geologically estimated age. The rocks from the Chanaral area is dated as 212.8 +- 8.6 Ma, which is correlated close to the Triassic-Jurassic boundary age. A K-Ar age of 196 +- 6 Ma was obtained on biotite in granite from Esmeralda between Ci Funcho and Chanaral. These age results demonstrate that no Precambrian plutonism occurred in the studied area, and that so-called Paleozoic granitic rocks in the Ci Funcho-Chanaral area are divided into Permian and early Mesozoic in age. Initial 87 Sr/ 86 Sr ratios of the ilmenite-series granitic rocks from the coastal region are 0.70641 (Valparaiso), 0.70635 (Ci Funcho) and 0.70455 (Chanaral). These relatively low ratios deny substantial crustal contribution to the granitoids. The initial ratios of magnetite-series granitoids from porphyry- and manto-type mineralized areas (Chiquicamata, El Salvador and Tocopilla) are as low as 0.70344 to 0.70464. (author)

Hydrogen impurity in SrTiO3: structure, electronic properties and migration

International Nuclear Information System (INIS)

Villamagua, Luis; Barreto, Rafael; Procel, Luis Miguel; Stashans, Arvids

2007-01-01

The present paper reports a computational investigation of the geometry and electronic structure as well as the migration of a hydrogen impurity in the cubic SrTiO 3 crystal. The study is done using an approach based on the Hartree-Fock theory and developed for periodic systems. It is found that the H impurity forms the so-called OH group at the equilibrium. Analysis of electron density within the defective region implies the enhancement in covalent chemical bonding. A possible defect migration has been also investigated

Renewable energy in Europe

International Nuclear Information System (INIS)

Deshaies, M.

2009-01-01

Europe's increasing demand for energy and its environmental preoccupations are creating a favourable environment for the development of renewable energy sources. This article stated that although many European countries have adopted voluntary policies since the 1990s to increase the use of renewable energy sources, they have not been developed in an equal or consistent manner. A table was included to show the consumption of renewable energies by country; the percentage of renewable energies in 1995 as compared to 2006; and the consumption of primary energy resources. Combined, Germany, Spain and Denmark produce 75 per cent of wind energy in Europe, while 75 per cent of Europe's hydroelectricity is produced in Norway, Sweden, France, Italy, Austria and Switzerland. Germany has also made significant contributions in developing biomass energy. The article emphasized that the development of renewable energy sources is limited by the fact that it cannot keep up with growing energy demands. In addition, renewable energies cannot yet replace all fossil fuel consumption in Europe because of the variation in development from one country to another. 1 ref., 2 tabs., 4 figs.

87Sr/86Sr variations in basalts of Late Eocene-Early Miocene series in Eastern Sikhoteh-Alin

International Nuclear Information System (INIS)

Esin, S.V.; Ponomarchuk, V.A.; Shipitsyn, Yu.G.; Palesskij, Yu.G.

1993-01-01

Late Eocene high-alumina and Oligocene high-alumina and magnesian basalts of the Neogene calc-alkaline series from the Eastern Sikhoteh-Alin are shown to have the following 87 Sr/ 86 Sr ratios: 0.70390-0.70465; 0.70347-0.70401, and the 0.70330-0.70347. Analysis of variations of Sr ratios, REE, HFSE, and LILE suggests that they are the products of successive melting of a multicomponent source containing the peridotite material of OIB- and MORB-types altered by fluids to a different degree and the pelagic sediments

Building a sustainable market for renewables

Energy Technology Data Exchange (ETDEWEB)

Rader, N.

1996-12-31

Opinions regarding marketing approaches for electricity generation from renewable resources are presented in the paper. The Renewables Portfolio Standard of the California Public Utilities Commission is described. This system is based on renewable energy credits. Other marketing approaches, including surcharges, auctioned renewables credit, green pricing, and green marketing are also assessed. It is concluded that the Renewables Portfolio Standard creates a stable economic environment for the renewable energy industries.

Renewable energy handbook

Energy Technology Data Exchange (ETDEWEB)

Fine, R

1976-01-01

The potential for renewable energy use in Canada is examined. It is pointed out that Canada can choose to begin to diversify its energy supply now, moving rapidly and smoothly towards an efficient energy society based on renewable energy sources; or, it can continue on its present course and face the possibility of being forced by necessity to make a later transition to renewable sources, probably with a great deal of economic and political disruption. The handbook begins with a discussion on major issues and options available. This second section deals with the technology, applications, and costs of direct solar energy utilization, solar thermal electricity generation, photovoltaic conversion, wind energy, biomass energy, tidal power, wave energy, ocean thermal energy, geothermal energy, heat pumps, and energy storage. Section three discusses how renewable energy might realistically supply Canada's energy requirements within a reasonable period of time. Some issues on how government, industry, and the individual may become involved to make this happen are suggested. A list of resource people and renewable energy businesses is provided in the last section. A recommended reading list and bibliography complete the handbook. (MCW)

Renewable energy education in Turkey

Energy Technology Data Exchange (ETDEWEB)

Acikgoz, Caglayan [Department of Chemical and Process Engineering, Faculty of Engineering, Bilecik University, P.O.11030, Bilecik (Turkey)

2011-02-15

Utilization of renewable energy sources and the application of environmentally sound energy technologies are essential to sustainable development and will help to secure the quality of living and the well-being of the future generations. Turkey presently has considerable renewable energy sources. The most important renewable sources are hydropower, wind, solar, geothermal, and biomass. The use of renewable energy as a topic to study energy and its forms permits a novel way to motivate students, particularly those who energy topics taking conscience with the environment. This paper presents the analysis and classification of renewable energy sources and how to find out their origin and a way to motivate students in energy topics related to renewable sources and also, the development of didactic competencies in special blended learning arrangements for educationalists, trainers and lecturers in adult education in the field of renewable energies in Turkey. (author)

Phase equilibria in the system As2-O5 - SrO

International Nuclear Information System (INIS)

Kasenov, B.K.; Ashlyaeva, I.V.

1993-01-01

T-x phase state diagram of As 2 O 5 -SrO system was investigated by the methods of physicochemical analysis. It was established that incongruently melting Sr(AsO 3 ) 2 (t mel 900 deg C), Sr 2 As 2 O 4 (t mel = 1140 deg C), Sr 4 As 2 O 9 (t mel = 1390 deg C) and congruently melting at 1635 deg C Sr 3 (AsO 4 ) 2 formed in the system. Eutectic points were revealed in the system: As 2 O 5 -Sr(AsO 3 ) 2 (15.0 mol % SrO, 700 deg C) and Sr 3 (AsO 4 ) 2 -Sr 4 As 2 O 9 (78 mol % SrO, 1370 deg C)

Does FDI influence renewable energy consumption? An analysis of sectoral FDI impact on renewable and non-renewable industrial energy consumption

International Nuclear Information System (INIS)

Doytch, Nadia; Narayan, Seema

2016-01-01

This study examines the link between foreign direct investment (FDI) and energy demand. FDI is a source of financing that allows businesses to grow. At the same time, FDI can be a source of innovation that promotes energy efficiency. Existing evidence on the impact of aggregate FDI inflows on energy consumption is scarce and inconclusive. In the current study, we disaggregate FDI inflows into mining, manufacturing, total services, and financial services components and examine the impact of these FDI flows on renewable – and non-renewable industrial energy – sources for 74 countries for the period 1985–2012. We employ a Blundell–Bond dynamic panel estimator to control for endogeneity and omitted variable biases in our panels. The results point broadly to an energy consumption-reducing effect with respect to non-renewable sources of energy and an energy consumption-augmenting effects with respect to renewable energy. We find that these effects vary in magnitude and significance by sectoral FDI. - Highlights: • FDI generally discourages the use of unclean energy. • Economic growth promotes non-renewable energy consumption. • Service FDI save energy and encourage the switch to renewable energy. • Mining FDI to low and lower middle-income panels save energy. • These results are mainly consistent with the FDI halo effect.

Low Thermal Conductivity of RE-Doped SrO(SrTiO3)1 Ruddlesden Popper Phase Bulk Materials Prepared by Molten Salt Method

Science.gov (United States)

Putri, Yulia Eka; Said, Suhana Mohd; Refinel, Refinel; Ohtaki, Michitaka; Syukri, Syukri

2018-04-01

The SrO(SrTiO3)1 (Sr2TiO4) Ruddlesden Popper (RP) phase is a natural superlattice comprising of alternately stacking perovskite-type SrTiO3 layers and rock salt SrO layers along the crystallographic c direction. This paper discusses the properties of the Sr2TiO4 and (La, Sm)-doped Sr2TiO4 RP phase synthesized via molten salt method, within the context of thermoelectric applications. A good thermoelectric material requires high electrical conductivity, high Seebeck coefficient and low thermal conductivity. All three conditions have the potential to be fulfilled by the Sr2TiO4 RP phase, in particular, the superlattice structure allows a higher degree of phonon scattering hence resulting in lowered thermal conductivity. In this work, the Sr2TiO4 RP phase is doped with Sm and La respectively, which allows injection of charge carriers, modification of its electronic structure for improvement of the Seebeck coefficient, and most significantly, reduction of thermal conductivity. The particles with submicron size allows excessive phonon scattering along the boundaries, thus reduces the thermal conductivity by fourfold. In particular, the Sm-doped sample exhibited even lower lattice thermal conductivity, which is believed to be due to the mismatch in the ionic radius of Sr and Sm. This finding is useful as a strategy to reduce thermal conductivity of Sr2TiO4 RP phase materials as thermoelectric candidates, by employing dopants of differing ionic radius.

State-scale evaluation of renewable electricity policy: The role of renewable electricity credits and carbon taxes

International Nuclear Information System (INIS)

Levin, Todd; Thomas, Valerie M.; Lee, Audrey J.

2011-01-01

We have developed a state-scale version of the MARKAL energy optimization model, commonly used to model energy policy at the US national scale and internationally. We apply the model to address state-scale impacts of a renewable electricity standard (RES) and a carbon tax in one southeastern state, Georgia. Biomass is the lowest cost option for large-scale renewable generation in Georgia; we find that electricity can be generated from biomass co-firing at existing coal plants for a marginal cost above baseline of 0.2-2.2 cents/kWh and from dedicated biomass facilities for 3.0-5.5 cents/kWh above baseline. We evaluate the cost and amount of renewable electricity that would be produced in-state and the amount of out-of-state renewable electricity credits (RECs) that would be purchased as a function of the REC price. We find that in Georgia, a constant carbon tax to 2030 primarily promotes a shift from coal to natural gas and does not result in substantial renewable electricity generation. We also find that the option to offset a RES with renewable electricity credits would push renewable investment out-of-state. The tradeoff for keeping renewable investment in-state by not offering RECs is an approximately 1% additional increase in the levelized cost of electricity. - Research Highlights: →We examine state-scale impacts of a renewable electricity standard and a carbon tax. →Georgia has low electricity prices and bioenergy is the main renewable option. →A carbon tax of $50/tCO 2 does not significantly increase renewable generation. →Renewable electricity credits divert renewable investment to other states. →Keeping renewable electricity generation in-state increases electricity costs by 1%.

Resilient Renewable Energy Microgrids

Energy Technology Data Exchange (ETDEWEB)

Anderson, Katherine H [National Renewable Energy Laboratory (NREL), Golden, CO (United States); DiOrio, Nicholas A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Butt, Robert S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Cutler, Dylan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Richards, Allison [Unaffiliated

2017-11-14

This presentation for the Cable-Tec Expo 2017 offers information about how renewable microgrids can be used to increase resiliency. It includes information about why renewable energy battery diesel hybrids microgrids should be considered for backup power, how to estimate economic savings of microgrids, quantifying the resiliency gain of microgrids, and where renewable microgrids will be successful.

Preparation of highly stable zeolite-alginate foam composite for strontium(90Sr) removal from seawater and evaluation of Sr adsorption performance.

Science.gov (United States)

Hong, Hye-Jin; Kim, Byoung-Gyu; Ryu, Jungho; Park, In-Su; Chung, Kang-Sup; Lee, Sang Moon; Lee, Jin-Bae; Jeong, Hyeon Su; Kim, Hyunchul; Ryu, Taegong

2018-01-01

Alginate bead is a promising strontium (Sr) adsorbent in seawater, but highly concentrated Na ions caused over-swelling and damaged the hydrogel bead. To improve the mechanical stability of alginate bead, flexible foam-type zeolite-alginate composite was synthesized and Sr adsorption performance was evaluated in seawater; 1-10% zeolite immobilized alginate foams were prepared by freeze-dry technique. Immobilization of zeolite into alginate foam converted macro-pores to meso-pores which lead to more compact structure. It resulted in less swollen composite in seawater medium and exhibited highly improved mechanical stability compared with alginate bead. Besides, Sr adsorption efficiency and selectivity were enhanced by immobilization of zeolite in alginate foam due to the increase of Sr binding sites (zeolite). In particular, Sr selectivity against Na was highly improved. The 10% zeolite-alginate foam exhibited a higher log K d of 3.3, while the pure alginate foam exhibited 2.7 in the presence of 0.1 M Na. Finally, in the real seawater, the 10% zeolite-alginate foam exhibited 1.5 times higher Sr adsorption efficiency than the pure alginate foam. This result reveals that zeolite-alginate foam composite is appropriate material for Sr removal in seawater due to its swelling resistance as well as improved Sr adsorption performance in complex media. Copyright © 2017 Elsevier Ltd. All rights reserved.

Geographical traceability based on 87Sr/86Sr indicator: a first approach for PDO Lambrusco wines from Modena.

Science.gov (United States)

Durante, Caterina; Baschieri, Carlo; Bertacchini, Lucia; Cocchi, Marina; Sighinolfi, Simona; Silvestri, Michele; Marchetti, Andrea

2013-12-01

The main goal of this study was to evaluate (87)Sr/(86)Sr ratio in different matrices, namely soils, branches, and grape juices, of an oenological food chain in order to develop a robust analytical strategy able to link the investigated food to its territory of origin. The (87)Sr/(86)Sr has been used as traceability marker and several aspects, affected its variability, i.e. geological features of the investigated area, the bio-available fraction of elements in the soils and the up-take of the plant, have been taken into account. Optimisation of an analytical procedure for the separation of Sr from its interferences and investigation of the analytical performances in terms of precision of used methodology have been carried out as well. This work highlighted a good match between the isotopic values monitored in the bio-available fraction of soils and their respective grape juices for almost all the investigated areas. The correlation with food satisfyingly improves when isotopic relative abundance values of branches vine are considered. Copyright © 2013 Elsevier Ltd. All rights reserved.

FEP report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Skagius, Kristina

2006-11-01

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

Renewables. The clean advantage

International Nuclear Information System (INIS)

Klein, A.

2006-01-01

Europe's big utilities are increasingly seeing renewable energy as a viable alternative to conventional forms of power generation which at present have disadvantages in terms of cost and/or environment. Europe's biggest 20 utilities aim to double their renewables capacity in the next five years and nearly 20 billion US dollars have been earmarked for such projects. This report by Emerging Energy Research discusses the likely trends for the next five years. The various sources of renewable energy and how they might be developed are discussed. The companies leading exploitation of renewables and their market share are named

The effect of secondary apatite on the initial 87Sr/86Sr ratio determination in granitic rocks: a case study of the Tadamigawa pluton, northeastern Japan

Science.gov (United States)

Wakasugi, Y.; Ichino, K.; Tanioka, Y.; Wakaki, S.; Tsuboi, M.; Ishikawa, T.

2017-12-01

Apatite is a major accessory mineral in igneous rocks. Because Rb contents in apatite are very low, 87Sr/86Sr ratios of magmatic apatite are useful to estimate the initial 87Sr/86Sr ratio (SrI) of igneous rocks. Secondary post-magmatic event such as hydrothermal alteration may also crystallize secondary apatite, which may inhibit the estimation of SrI of igneous rocks. In this study, we examine the effects of secondary apatite on the initial 87Sr/86Sr ratio determination of granitic rocks by using acid leaching technique. Leached apatite samples were first separated from the whole rock powder as a heavy mineral fraction by heavy liquid technique, and the heavy mineral fraction was then leached by 3 M HNO3. The isotopic ratios of Sr and the concentrations of Rb and Sr were analyzed by TIMS and ICP-MS at Kochi Core Center, respectively. The Tadamigawa Older-stage granites, which locate in the Taishaku Mountains at the northeastern part of Japan, intrude into the Ashio Jurassic complex, and the ages of these rocks are late Cretaceous to Paleogene. The U-Pb ages of zircon and the K-Ar ages of biotite for these rocks are c. 100 Ma [1, 2]. Rb-Sr whole-rock isochron age of the pluton is 96.5 ± 1.3 Ma (SrI = 0.70534 ± 0.00003) and it is concordant with other radiometric ages. Rb-Sr mineral isochron ages range from 84.4 to 97.3 Ma and these ages are relatively younger than the Rb-Sr whole-rock isochron age. The difference among radiometric ages may reflect the difference of the closure temperature in each isotopic system. The Tadamigawa Older-stage granites have SrI for Rb-Sr mineral isochron range from 0.7053 to 0.7061 and are very similar to that (0.70534) for Rb-Sr whole-rock isochron. These may suggest that the Tadamigawa Older-stage granites are generated from same parental magma. However, 87Sr/86Sr ratios of the leached apatite samples were 0.70544-0.70856 and are relatively higher than SrI obtained from the Rb-Sr mineral isochrons (0.7053-0.7061). This result

Renewable energy

DEFF Research Database (Denmark)

Olsen, Birgitte Egelund

2016-01-01

Renewable energy projects are increasingly confronted by local opposition, which delays and sometimes even prevents their implementation. This reflects the frequent gap between support for the general idea of renewables as a strategy for reducing carbon emissions, and acceptance of renewable energy...... installations in the local landscape. A number of countries have introduced financial incentives to promote community acceptance. The tool box of incentives is still limited but in recent years it has been expanded to address local concerns. Certain general characteristics can be identified, suggesting...... that there are at least three distinct categories of incentives: individual compensation, community benefits and ownership measures. Local opposition must be approached with caution, as financial incentives to promote local acceptance can be seen as buying consent or even ‘bribery’, stirring up further opposition....

Spin-polarized electron gas in Co2MSi/SrTiO3(M= Ti, V, Cr, Mn, and Fe) heterostructures

KAUST Repository

Nazir, S.; Schwingenschlö gl, Udo

2016-01-01

Spin-polarized density functional theory is used to study the TiO2 terminated interfaces between the magnetic Heusler alloys Co2Si (M = Ti, V, Cr, Mn, and Fe) and the non-polar band insulator SrTiO3. The structural relaxation at the interface turns

NRC's license renewal regulations

International Nuclear Information System (INIS)

Akstulewicz, Francis

1991-01-01

In order to provide for the continuity of the current generation of nuclear power plant operating licenses and at the same time ensure the health and safety of the public, and the quality of the environment, the US Nuclear Regulatory Commission (NRC) established a goal of developing and issuing regulations and regulatory guidance for license renewal in the early 1990s. This paper will discuss some of those activities underway to achieve this goal. More specifically, this paper will discuss the Commission's regulatory philosophy for license renewal and the two major license renewal rule makings currently underway. The first is the development of a new Part 54 to address procedural and technical requirements for license renewal; the second is a revision to existing Part 51 to exclude environmental issues and impacts from consideration during the license renewal process. (author)

A method for determination of 90Sr in vegetation

International Nuclear Information System (INIS)

Nygren, U.

1998-12-01

This report describes a method for determination of 90 Sr in vegetation. The method consists of wet-ashing the samples and separating Sr from the sample matrix by oxalate precipitation and extraction chromatography. 90 Y ingrowth is awaited after which Y is separated from Sr and 90 Y measured in a proportional counter. The method has been applied on two reference materials and the 90 Sr results agree well with the recommended values. The method has also been used on 20 samples of blueberry twigs and the mean recovery of Sr was 74%

Migration and distribution of 90Sr in soil

International Nuclear Information System (INIS)

Yang Juncheng; Zhu Yongyi; Chen Jingjian

1993-01-01

The migration and distribution of radionuclide 90 Sr were conducted by the analysis of 97 soil longitudinal sections under natural conditions and by pot experiments with fallout and 90 Sr solution, respectively. Spring wheat and rice were employed in the pot experiments. The result showed that the radionuclide 90 Sr was mainly accumulated in the topsoil 0-10 cm under both of the natural and laboratory conditions. The vertical distribution of 90 Sr in soil agreed with the power function, which obtained was Y = 75.78 X -0.527 ; r = -0.986; n = 97. The existing forms of 90 Sr from fallout in soil, only 0.02-0.03% was in a soluble form and 0.06-0.07% in non-replaceable form

OpenNebula KVM SR-IOV driver

CSIR Research Space (South Africa)

Macleod, D

2013-05-01

Full Text Available With the recent release of an OFED which supports SR-IOV on Infiniband HCAs it is now possible to use verbs from inside a VM. This VMM driver supports these Infiniband HCAs, and any other SR-IOV network device, in OpenNebula....

Renewables 2013. Global Status Report

Energy Technology Data Exchange (ETDEWEB)

Sawin, J. L. [and others

2013-07-01

Renewable energy markets, industries, and policy frameworks have evolved rapidly in recent years. The Renewables Global Status Report provides a comprehensive and timely overview of renewable energy market, industry, investment, and policy developments worldwide. It relies on the most recent data available, provided by many contributors and researchers from around the world, all of which is brought together by a multi-disciplinary authoring team. The report covers recent developments, current status, and key trends; by design, it does not provide analysis or forecasts. This latest Renewables Global Status Report saw: a shift in investment patterns that led to a global decrease in clean energy investment; continuing growth in installed capacity due to significant technology cost reductions and increased investment in developing countries; renewables progressively supplementing established electricity systems, demonstrating that the implementation of suitable policies can enable the successful integration of higher shares of variable renewables; and the emergence of integrated policy approaches that link energy efficiency measures with the implementation of renewable energy technologies.

Renewables 2018 - Global status report. A comprehensive annual overview of the state of renewable energy. Advancing the global renewable energy transition - Highlights of the REN21 Renewables 2018 Global Status Report in perspective

International Nuclear Information System (INIS)

Sawin, Janet L.; Sverrisson, Freyr; Rutovitz, Jay; Dwyer, Scott; Teske, Sven; Murdock, Hannah E.; Adib, Rana; Guerra, Flavia; Murdock, Hannah E.; Blanning, Linh H.; Guerra, Flavia; Hamirwasia, Vibhushree; Misra, Archita; Satzinger, Katharina; Williamson, Laura E.; Lie, Mimi; Nilsson, Anna; Aberg, Emma; Weckend, Stephanie; Wuester, Henning; Ferroukhi, Rabia; Garcia, Celia; Khalid, Arslan; Renner, Michael; Taylor, Michael; Epp, Barbel; Seyboth, Kristin; Skeen, Jonathan; Kamiya, George; Munuera, Luis; Appavou, Fabiani; Brown, Adam; Kondev, Bozhil; Musolino, Evan; Brown, Adam; Mastny, Lisa; Arris, Lelani

2018-06-01

REN21's Renewables 2018 Global Status Report presents developments and trends through the end of 2017, as well as observed trends from early 2018 where available. Renewable power accounted for 70% of net additions to global power generating capacity in 2017, the largest increase in renewable power capacity in modern history, according to REN21's Renewables 2018 Global Status Report (GSR). But the heating, cooling and transport sectors - which together account for about four-fifths of global final energy demand - continue to lag far behind the power sector. The GSR, published today, is the most comprehensive annual overview of the state of renewable energy worldwide. New solar photovoltaic (PV) capacity reached record levels: Solar PV additions were up 29% relative to 2016, to 98 GW. More solar PV generating capacity was added to the electricity system than net capacity additions of coal, natural gas and nuclear power combined. Wind power also drove the uptake of renewables with 52 GW added globally. Investment in new renewable power capacity was more than twice that of net, new fossil fuel and nuclear power capacity combined, despite large, ongoing subsidies for fossil fuel generation. More than two-thirds of investments in power generation were in renewables in 2017, thanks to their increasing cost-competitiveness - and the share of renewables in the power sector is expected to only continue to rise. Investment in renewables was regionally concentrated: China, Europe and the United States accounted for nearly 75% of global investment in renewables in 2017. However, when measured per unit of gross domestic product (GDP), the Marshall Islands, Rwanda, the Solomon Islands, Guinea Bissau, and many other developing countries are investing as much as or more in renewables than developed and emerging economies. Both energy demand and energy-related CO 2 emissions rose substantially for the first time in four years. Energy-related CO 2 emissions rose by 1

Abscisic Acid (ABA) Regulation of Arabidopsis SR Protein Gene Expression

Science.gov (United States)

Cruz, Tiago M. D.; Carvalho, Raquel F.; Richardson, Dale N.; Duque, Paula

2014-01-01

Serine/arginine-rich (SR) proteins are major modulators of alternative splicing, a key generator of proteomic diversity and flexible means of regulating gene expression likely to be crucial in plant environmental responses. Indeed, mounting evidence implicates splicing factors in signal transduction of the abscisic acid (ABA) phytohormone, which plays pivotal roles in the response to various abiotic stresses. Using real-time RT-qPCR, we analyzed total steady-state transcript levels of the 18 SR and two SR-like genes from Arabidopsis thaliana in seedlings treated with ABA and in genetic backgrounds with altered expression of the ABA-biosynthesis ABA2 and the ABA-signaling ABI1 and ABI4 genes. We also searched for ABA-responsive cis elements in the upstream regions of the 20 genes. We found that members of the plant-specific SC35-Like (SCL) Arabidopsis SR protein subfamily are distinctively responsive to exogenous ABA, while the expression of seven SR and SR-related genes is affected by alterations in key components of the ABA pathway. Finally, despite pervasiveness of established ABA-responsive promoter elements in Arabidopsis SR and SR-like genes, their expression is likely governed by additional, yet unidentified cis-acting elements. Overall, this study pinpoints SR34, SR34b, SCL30a, SCL28, SCL33, RS40, SR45 and SR45a as promising candidates for involvement in ABA-mediated stress responses. PMID:25268622

SR-71 Pilot Stephen (Steve) D. Ishmael

Science.gov (United States)

1992-01-01

NASA research pilot Stephen D. Ishmael is pictured here in front of an SR-71 Blackbird on the ramp at the Dryden Flight Research Center, Edwards, California. Ishmael was one of two NASA research pilots assigned to the SR-71 high speed research program in the early 1990s at NASA's Dryden Flight Research Facility (redesignated the Dryden Flight Research Center in 1994), Edwards, California. Ishmael became a NASA research pilot in 1977. Data from the SR-71 program will be used to aid designers of future supersonic aircraft and propulsion systems. Two SR-71 aircraft have been used by NASA as testbeds for high-speed and high-altitude aeronautical research. The aircraft, an SR-71A and an SR-71B pilot trainer aircraft, have been based here at NASA's Dryden Flight Research Center, Edwards, California. They were transferred to NASA after the U.S. Air Force program was cancelled. As research platforms, the aircraft can cruise at Mach 3 for more than one hour. For thermal experiments, this can produce heat soak temperatures of over 600 degrees Fahrenheit (F). This operating environment makes these aircraft excellent platforms to carry out research and experiments in a variety of areas -- aerodynamics, propulsion, structures, thermal protection materials, high-speed and high-temperature instrumentation, atmospheric studies, and sonic boom characterization. The SR-71 was used in a program to study ways of reducing sonic booms or over pressures that are heard on the ground, much like sharp thunderclaps, when an aircraft exceeds the speed of sound. Data from this Sonic Boom Mitigation Study could eventually lead to aircraft designs that would reduce the 'peak' overpressures of sonic booms and minimize the startling affect they produce on the ground. One of the first major experiments to be flown in the NASA SR-71 program was a laser air data collection system. It used laser light instead of air pressure to produce airspeed and attitude reference data, such as angle of attack and

Renewable energy systems the choice and modeling of 100% renewable solutions

CERN Document Server

Lund, Henrik

2009-01-01

How can society quickly convert to renewable energy? Can worldwide energy needs ever be met through 100% renewable sources? The answers to these questions rest largely on the perception of choice in the energy arena. It is of pivotal importance that engineers, researchers and policymakers understand what choices are available, and reasonable, when considering the design and deployment of new energy systems. The mission of this new book, written by one of the world's foremost experts in renewable power, is to arm these professionals with the tools and methodologies necessary to make smart choic

Marine Renewable Energies

DEFF Research Database (Denmark)

Azzellino, Arianna; Conley, Daniel; Vicinanza, Diego

2013-01-01

Countries with coastlines may have valuable renewable energy resources in the form of tides, currents, waves, and offshorewind.The potential to gather energy from the sea has recently gained interest in several nations, so Marine Renewable Energy Installations (hereinafter MREIs) will likely become...

(Ba+Sr)/Ti ratio dependence of the dielectric properties for (Ba0.5Sr0.5)TiO3 thin films prepared by ion beam sputtering

Science.gov (United States)

Yamamichi, Shintaro; Yabuta, Hisato; Sakuma, Toshiyuki; Miyasaka, Yoichi

1994-03-01

(Ba0.5Sr0.5)TiO3 thin films were prepared by ion beam sputtering from powder targets with (Ba+Sr)/Ti ratios ranging from 0.80 to 1.50. All of the perovskite (Ba,Sr)TiO3 films were single phase except for the film with a (Ba+Sr)/Ti ratio of 1.41. The dielectric constant values notably depended on the (Ba+Sr)/Ti ratio for films thicker than 70 nm. The highest dielectric constant of 580 was achieved for the 5% (Ba+Sr) rich film. This (Ba+Sr)/Ti ratio dependence was diminished by the thickness dependence for thinner films. The grain sizes for the 9% (Ba+Sr) rich film and for the 6% (Ba+Sr) poor film ranged from 70 to 100 nm and from 30 to 60 nm, respectively. This grain size difference could explain why slightly A-site rich (Ba,Sr)TiO3 films have a larger dielectric constant than A-site poor films.

Ab initio study of the RbSr electronic structure: Potential energy curves, transition dipole moments, and permanent electric dipole moments

Energy Technology Data Exchange (ETDEWEB)

Pototschnig, Johann V., E-mail: johann.pototschnig@tugraz.at; Krois, Günter; Lackner, Florian; Ernst, Wolfgang E., E-mail: wolfgang.ernst@tugraz.at [Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, A-8010 Graz (Austria)

2014-12-21

Excited states and the ground state of the diatomic molecule RbSr were calculated by post Hartree-Fock molecular orbital theory up to 22 000 cm{sup −1}. We applied a multireference configuration interaction calculation based on multiconfigurational self-consistent field wave functions. Both methods made use of effective core potentials and core polarization potentials. Potential energy curves, transition dipole moments, and permanent electric dipole moments were determined for RbSr and could be compared with other recent calculations. We found a good agreement with experimental spectra, which have been obtained recently by helium nanodroplet isolation spectroscopy. For the lowest two asymptotes (Rb (5s {sup 2}S) + Sr (5s4d {sup 3}P°) and Rb (5p {sup 2}P°) + Sr (5s{sup 2} {sup 1}S)), which exhibit a significant spin-orbit coupling, we included relativistic effects by two approaches, one applying the Breit-Pauli Hamiltonian to the multireference configuration interaction wave functions, the other combining a spin-orbit Hamiltonian and multireference configuration interaction potential energy curves. Using the results for the relativistic potential energy curves that correspond to the Rb (5s {sup 2}S) + Sr (5s4d {sup 3}P°) asymptote, we have simulated dispersed fluorescence spectra as they were recently measured in our lab. The comparison with experimental data allows to benchmark both methods and demonstrate that spin-orbit coupling has to be included for the lowest states of RbSr.

Ab initio study of the RbSr electronic structure: potential energy curves, transition dipole moments, and permanent electric dipole moments.

Science.gov (United States)

Pototschnig, Johann V; Krois, Günter; Lackner, Florian; Ernst, Wolfgang E

2014-12-21

Excited states and the ground state of the diatomic molecule RbSr were calculated by post Hartree-Fock molecular orbital theory up to 22 000 cm(-1). We applied a multireference configuration interaction calculation based on multiconfigurational self-consistent field wave functions. Both methods made use of effective core potentials and core polarization potentials. Potential energy curves, transition dipole moments, and permanent electric dipole moments were determined for RbSr and could be compared with other recent calculations. We found a good agreement with experimental spectra, which have been obtained recently by helium nanodroplet isolation spectroscopy. For the lowest two asymptotes (Rb (5s (2)S) + Sr (5s4d (3)P°) and Rb (5p (2)P°) + Sr (5s(2) (1)S)), which exhibit a significant spin-orbit coupling, we included relativistic effects by two approaches, one applying the Breit-Pauli Hamiltonian to the multireference configuration interaction wave functions, the other combining a spin-orbit Hamiltonian and multireference configuration interaction potential energy curves. Using the results for the relativistic potential energy curves that correspond to the Rb (5s (2)S) + Sr (5s4d (3)P°) asymptote, we have simulated dispersed fluorescence spectra as they were recently measured in our lab. The comparison with experimental data allows to benchmark both methods and demonstrate that spin-orbit coupling has to be included for the lowest states of RbSr.

Sr and Nd isotope systematics in fish teeth

International Nuclear Information System (INIS)

Staudigel, H.; Zindler, A.

1985-01-01

High concentrations of Sr and Nd in fish teeth apatite (up to 2000 and 3800 ppm, respectively) make them relatively impervious to diagenetic overprints and allow high-precision analysis of 87 Sr/ 86 Sr and 143 Nd/ 144 Nd of very small amounts of material. 87 Sr/ 86 Sr ratios of 14 Cenozoic samples ( 87 Sr/ 86 Sr stratigraphic dating. A compilation of published 143 Nd/ 144 Nd data from recent Mn-nodules and marine Fe/Mn deposits shows that the North-Central Pacific Ocean and the major portion of the Atlantic Ocean display distinctly different, narrow ranges in isotopic compositions. Between these two areas, the 143 Nd/ 144 Nd of Mn-nodules vary systematically towards intermediate compositions in the Southern Oceans, reflecting the communication between the Atlantic and Pacific Oceans through the eastward moving Antarctic Circumpolar Current. The 143 Nd/ 144 Nd of the 2-55 Ma old fish teeth analyzed are typically close to the range of 143 Nd/ 144 Nd in Recent Mn-nodules and seawater for the respective ocean and, thus, indicate no significant change through this time period. The 143 Nd/ 144 Nd of fish teeth from the North Pacific Ocean are highest during periods of high aeolian sedimentation. (orig.)

Future Costs, Benefits, and Impacts of Renewables Used to Meet U.S. Renewable Portfolio Standards

Energy Technology Data Exchange (ETDEWEB)

2016-12-01

This brochure provides a brief overview of the report titled 'A Prospective Analysis of the Costs, Benefits, and Impacts of U.S. Renewable Portfolio Standards.' The report evaluates the future costs, benefits, and other impacts of renewable energy used to meet current state renewable portfolio standards (RPSs). It also examines a future scenario where RPSs are expanded. The analysis examines changes in electric system costs and retail electricity prices, which include all fixed and operating costs, including capital costs for all renewable, non-renewable, and supporting (e.g., transmission and storage) electric sector infrastructure; fossil fuel, uranium, and biomass fuel costs; and plant operations and maintenance expenditures. The analysis evaluates three specific benefits: air pollution, greenhouse gas emissions, and water use. It also analyzes two other impacts, renewable energy workforce and economic development, and natural gas price suppression. The analysis finds that the benefits or renewable energy used to meet RPS polices exceed the costs, even when considering the highest cost and lowest benefit outcomes.

Aldo Leopold's land health from a resilience point of view: self-renewal capacity of social-ecological systems.

Science.gov (United States)

Berkes, Fikret; Doubleday, Nancy C; Cumming, Graeme S

2012-09-01

Health approaches to ecology have a strong basis in Aldo Leopold's thinking, and contemporary ecohealth in turn has a strong philosophical basis in Leopold. To commemorate the 125th anniversary of Leopold's birth (1887-1948), we revisit his ideas, specifically the notions of stewardship (land ethic), productive use of ecosystems (land), and ecosystem renewal. We focus on Leopold's perspective on the self-renewal capacity of the land, as understood in terms of integrity and land health, from the contemporary perspective of resilience theory and ecological theory more generally. Using a broad range of literature, we explore insights and implications of Leopold's work for today's human-environment relationships (integrated social-ecological systems), concerns for biodiversity, the development of agency with respect to stewardship, and key challenges of his time and of ours. Leopold's seminal concept of land health can be seen as a triangulation of productive use, self-renewal, and stewardship, and it can be reinterpreted through the resilience lens as the health of social-ecological systems. In contemporary language, this involves the maintenance of biodiversity and ecosystem services, and the ability to exercise agency both for conservation and for environmental justice.

Tracing sediment sources in upstream agricultural catchments: contribution of elemental geochemistry, 87Sr/86Sr ratio and radionuclides measurements

International Nuclear Information System (INIS)

Le-Gall, Marion

2016-01-01

Soil erosion is recognized as one of the main processes of land degradation in agricultural environments. This study develops an original fingerprinting method to examine sediment source contributions in two contrasted agricultural catchments. Several properties were used to trace sediment lithological sources ( 87 Sr/ 86 Sr ratios, elemental concentrations), soil surface and subsurface sources ( 137 Cs) and to quantify their temporal dynamics ( 7 Be, 210 Pb xs ). In the Louroux catchment (24 km 2 , France), representative of drained areas of Northwestern Europe, results showed the dominant contribution of very fine particles (≤2 μm) transiting through the tile drainage system to suspended sediment. Sediment accumulated in the river channel was mainly exported during the two first floods investigated in 2013 whereas the next event was characterized by the transport of sediment eroded from the cultivated soil surface. Mixing models were used, and results indicated that surface sources contributed the majority of sediment deposited in the pond, at the outlet of the catchment. The two lithological sources, discriminated using 87 Sr/ 86 Sr ratios, contributed in similar proportions to downstream pond sediment. In contrast, significant variations were observed since the 1950's. These changes may be related to the progressive implementation of land consolidation schemes within the catchment. Results obtained in the Louroux catchment revealed the potential of 87 Sr/ 86 Sr ratios to trace sediment lithological sources. The methodology was then applied to the larger and steeper Guapore catchment (2000 km 2 , Brazil), exposed to a more erosive climate and characterized by contrasted laterite soils. 87 Sr/ 86 Sr ratios and elements that discriminated the five soil types found in the catchment were incorporated in mixing models. Results showed that the major part of sediment was supplied by soils located in lower catchment parts. This result suggests the higher

Renewables 2015 global status report - Annual Reporting on Renewables: Ten years of excellence

International Nuclear Information System (INIS)

Sawin, Janet L.; Sverrisson, Freyr; Rickerson, Wilson; Lins, Christine; Williamson, Laura E.; Adib, Rana; Murdock, Hannah E.; Musolino, Evan; Hullin, Martin; Reith, Ayla; Valero, Alana; Mastny, Lisa; Petrichenko, Ksenia; Seyboth, Kristin; Skeen, Jonathan; Sovacool, Benjamin; Wouters, Frank; Martinot, Eric

2015-01-01

Renewable energy continued to grow in 2014 against the backdrop of increasing global energy consumption, particularly in developing countries, and a dramatic decline in oil prices during the second half of the year. Despite rising energy use, for the first time in four decades, global carbon emissions associated with energy consumption remained stable in 2014 while the global economy grew; this stabilisation has been attributed to increased penetration of renewable energy and to improvements in energy efficiency. Globally, there is growing awareness that increased deployment of renewable energy (and energy efficiency) is critical for addressing climate change, creating new economic opportunities, and providing energy access to the billions of people still living without modern energy services. Although discussion is limited to date, renewables also are an important element of climate change adaptation, improving the resilience of existing energy systems and ensuring delivery of energy services under changing climatic conditions. Renewable energy provided an estimated 19.1% of global final energy consumption in 2013, and growth in capacity and generation continued to expand in 2014. Heating capacity grew at a steady pace, and the production of bio-fuels for transport increased for the second consecutive year, following a slowdown in 2011-2012. The most rapid growth, and the largest increase in capacity, occurred in the power sector, led by wind, solar PV, and hydropower. Growth has been driven by several factors, including renewable energy support policies and the increasing cost-competitiveness of energy from renewable sources. In many countries, renewables are broadly competitive with conventional energy sources. At the same time, growth continues to be tempered by subsidies to fossil fuels and nuclear power, particularly in developing countries. Although Europe remained an important market and a centre for innovation, activity continued to shift towards other

Renewable energy partnerships in development cooperation: Towards a relational understanding of technical assistance

International Nuclear Information System (INIS)

Kruckenberg, Lena J.

2015-01-01

Recent decades have witnessed a surge in international programmes established to assist the adoption of renewable energy technologies (RETs) in low and lower-middle income countries. So far, such programmes have yielded mixed success. While partnerships between international, national and local organisations have become the pre-eminent model for RET programmes, we know relatively little about their contribution. This article traces the role of renewable energy partnerships in development cooperation, shifting the analytical emphasis from barriers and drivers to key actors and their relationships. It presents a relational approach for the analysis of development assistance for renewable energy, drawing on theories concerning the role of strong and weak ties in inter-organisational networks. Through an analysis of seven empirical cases from Central America, the article provides insights into how different forms of inter-organisational relationships can facilitate implementation of RET programmes but do not necessarily enhance the capacities of local organisations in a way to support a more sustainable adoption of RETs. On the basis of this analysis, theoretical and policy implications are given concerning the potential of relational approaches for researching technology diffusion processes, and the role of strong and weak ties for the success – or failure – of renewable energy partnerships. - Highlights: • Study of renewable energy partnerships in development cooperation. • Relational framework for analysis of inter-organisational technology diffusion. • Empirical cases of renewable energy partnerships in Central America. • Different types of network relationships enable/inhibit sustainable adoption. • Three policy recommendations for programme development

Localized versus itinerant states created by multiple oxygen vacancies in SrTiO3

Science.gov (United States)

Jeschke, Harald O.; Shen, Juan; Valentí, Roser

2015-02-01

Oxygen vacancies in strontium titanate surfaces (SrTiO3) have been linked to the presence of a two-dimensional electron gas with unique behavior. We perform a detailed density functional theory study of the lattice and electronic structure of SrTiO3 slabs with multiple oxygen vacancies, with a main focus on two vacancies near a titanium dioxide terminated SrTiO3 surface. We conclude based on total energies that the two vacancies preferably inhabit the first two layers, i.e. they cluster vertically, while in the direction parallel to the surface, the vacancies show a weak tendency towards equal spacing. Analysis of the nonmagnetic electronic structure indicates that oxygen defects in the surface TiO2 layer lead to population of Ti {{t}2g} states and thus itinerancy of the electrons donated by the oxygen vacancy. In contrast, electrons from subsurface oxygen vacancies populate Ti eg states and remain localized on the two Ti ions neighboring the vacancy. We find that both the formation of a bound oxygen-vacancy state composed of hybridized Ti 3eg and 4p states neighboring the oxygen vacancy as well as the elastic deformation after extracting oxygen contribute to the stabilization of the in-gap state.

Kinetics of distribution of 90Sr in Beijing-white layers

International Nuclear Information System (INIS)

Shang Zhaorong; Xu Shiming; Zhao Wenhu; Hou Lanxin

1993-08-01

The experiment feeding 90 Sr(NO 3 ) 2 in the range of 1.85 x 10 2 to 1.85 x 10 5 Bq/chicken was carried out with 45 Beijing-white layers to observe the regular pattern of absorption and distribution of 90 Sr in organs and tissues. The results are summarized as follows: the uptake rate of 90 Sr by layer through oral feeding is very low. Most part of 90 Sr drains away from body with daily excreta and egg. The accumulation of 90 Sr in the body is low and about 70% is in the bone. About 99% of 90 Sr in egg is concentrated in the eggshell. The order of absorptivity of 90 Sr in tissues is bone>feather>muscle>blood>viscera. The absorption coefficient of 90 Sr in organs and tissues in different stages with different feeding volumes has been calculated

The accumulation and elimination of 89Sr in tea leaves

International Nuclear Information System (INIS)

Zhang Yongxi; Wang Shouxiang; Chen Chuanqun; Sun Zhiming; Hu Bingmin; Huang Dan

1995-01-01

The 89 Sr was added to the tea tree-soil system by different ways. The 89 Sr in the system through the over-ground part of tea tree, was much more than that through soil. The 89 Sr concentration in older leaves was higher than in shoot for a definite treatment. The accumulation elimination law of 89 Sr in leaves varied with the treatments. For the treatment through the over-ground part, the 89 Sr concentration in older leaves and shoot was monotonously decreased with time increasing. But for the treatment through soil the 89 Sr concentration in shoot was increased to reach a peak value, and then decreased slowly; while the 89 Sr concentration in older leaves increased quickly in a period, then increased slowly to attain a saturated value. In addition, the concentration factor of 89 Sr in older leaves and shoot were determined

Rb-Sr and Nd-Sr isotope geochemistry and petrogenesis of the Misho Mountains mafic dikes (NW Iran

Directory of Open Access Journals (Sweden)

Maryam Ahankoub

2017-02-01

Full Text Available Introduction There are some theories about the Paleotethys event during the Paleozoic that have been proposed by geologists (Metcalfe, 2006. Some scientist offered some pieces of evidence about the northern margin of Gondwana (Zhu et al., 2010. The Paleotethys Ocean and Hercynian orogenic report first in Iran, have been Offered from the Morrow and Misho Mountain (Eftekharnejad, 1981. Misho Mountains is located between the north and south Misho faults and cause the formation of a positive flower structure (Moayyed and Hossainzade, 2011. There is theory about Misho southern fault as the best candidate of the Paleotethys suture zone (Moayyed and Hossainzade, 2011. Geochemistry and Sr –Nd isotopic data of the A2 granitic and Synite rocks of the East Misho, indicate that the magmatism post collision has occurred in the active continental margin by extensional zones of the following the closure of the Paleotethys (Ahankoub, 2012. Granite and syenite rocks have been cut by mafic dikes. Mafic dikes are often formed in extensional tectonic settings related to mantle plume or continental break –up (Zhu et al., 2009. In this paper, we use the geochemistry and Nd-Sr isotope data to determined petrogenesis, tectono-magmatic setting and age of Misho mafic dikes. Materials and methods After petrography study of 30 thin sections of mafic dike rocks, 8 samples were selected for whole-rock chemical analyses using ICP-MS and ICP-AES instruments by ACME Company in Vancouver, Canada. We prepared 6 sample For Sm-Nd and Rb-Sr analysis. Sr and Nd isotope ratios were measured with a thermal ionization mass spectrometer, VG Sector 54–30 at the Nagoya University. The isotope abundances of Rb, Sr, Nd, and Sm were measured by the ID method with a Finnigan MAT Thermoquad THQ thermal ionization quadrupole mass spectrometer at the Nagoya University. NBS987 and JNdi-1 were measured as natural Sr and Nd isotope ratio standards (Tanaka et al., 2000. Averages and 2σ errors

Interim FEP report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina (ed.) [Kemakta Konsult AB, Stockholm (Sweden)

2004-08-01

This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

Interim FEP report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Skagius, Kristina

2004-08-01

This report describes the work with identification and structuring of features, events and processes (FEPs) that has been carried out within the scope of the SR-Can safety assessment up to the time of the interim reporting of the project. The overall objective of the work is to develop a database of features, events and processes in a format that would facilitate both a systematic analysis of FEPs and documentation of the FEP analysis as well as facilitate revisions and updates to be made in connection with new safety assessments. This overall objective also includes the development of procedures for a systematic FEP analysis as well as to apply these procedures in order to arrive at an SR-Can version of the FEP database. The work started by implementing the content of the SR 97 Process report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs from the audit were sorted into three main categories in the SR-Can database i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. These groups of FEPs were further processed for making decisions on how to handle these FEPs in the assessment. Biosphere processes were not included in the SR 97 Process report and there is thus not the same basis for updating these descriptions as for the engineered barriers and the geosphere. All biosphere FEPs from the audit have therefore been compiled in a single category in the database, but remain to be further handled. FEPs were also categorised as irrelevant or as being related to methodology on a general

Streamlining the license renewal review process

International Nuclear Information System (INIS)

Dozier, J.; Lee, S.; Kuo, P.T.

2001-01-01

The staff of the NRC has been developing three regulatory guidance documents for license renewal: the Generic Aging Lessons Learned (GALL) report, Standard Review Plan for License Renewal (SRP-LR), and Regulatory Guide (RG) for Standard Format and Content for Applications to Renew Nuclear Power Plant Operating Licenses. These documents are designed to streamline the license renewal review process by providing clear guidance for license renewal applicants and the NRC staff in preparing and reviewing license renewal applications. The GALL report systematically catalogs aging effects on structures and components; identifies the relevant existing plant programs; and evaluates the existing programs against the attributes considered necessary for an aging management program to be acceptable for license renewal. The GALL report also provides guidance for the augmentation of existing plant programs for license renewal. The revised SRP-LR allows an applicant to reference the GALL report to preclude further NRC staff evaluation if the plant's existing programs meet the criteria described in the GALL report. During the review process, the NRC staff will focus primarily on existing programs that should be augmented or new programs developed specifically for license renewal. The Regulatory Guide is expected to endorse the Nuclear Energy Institute (NEI) guideline, NEI 95-10, Revision 2, entitled 'Industry Guideline for Implementing the Requirements of 10 CFR Part 54 - The License Renewal Rule', which provides guidance for preparing a license renewal application. This paper will provide an introduction to the GALL report, SRP-LR, Regulatory Guide, and NEI 95-10 to show how these documents are interrelated and how they will be used to streamline the license renewal review process. This topic will be of interest to domestic power utilities considering license renewal and international ICONE participants seeking state-of-the-art information about license renewal in the United States

The renewable energy market in Australia

International Nuclear Information System (INIS)

2002-01-01

Australia is committed to an 8 per cent reduction in its emissions of greenhouse gases above 1990 levels as a result of the Kyoto Protocol for the period 2008-2012. At present, the emissions stand at 17.4 per cent above 1990 levels. Total electrical power in Australia resulting from renewable energy is in the order of 10.5 per cent. A mandatory renewable energy target of 9500 gigawatt hour (GWh) of extra renewable energy is to be produced annually by 2010, under the Renewable Energy (Electricity) Act. An emissions trading system has been implemented, involving one renewable energy certificate (REC) created for each megawatt hour of renewable energy generated. A significant expansion of the demand for renewable energy is expected in Australia over the next ten years, according to the Australian Greenhouse Office. Increased opportunities for local and international firms operating in the field of renewable energy are being created by the Australian government through initiatives such as the Renewable Energy Commercialization Program, and the Renewable Remote Power Generation Program. Solar, biomass, and wind power are comprised in the wealth of renewable energy resources in Australia. The market remains largely undeveloped. Firms from the United States and the European Union are the leading exporters of renewable energy technology to Australia. Public utilities and independent power producers having entered the deregulated electricity market are the consumers of renewable energy technology and services. A country with minimal duties in most cases, Australia has much in common with Canada, including similar regulatory and legal systems. Australia applies a 10 per cent goods and services tax, which would apply to Canadian exports. It was advised to consult the Australian Customs Service for additional information concerning duties that might be applicable to the renewable energy industry. 28 refs., 3 tabs

High-pressure structural behavior of the double perovskite Sr2CrReO6: an experimental and theoretical study

DEFF Research Database (Denmark)

Olsen, J.S.; Gerward, Leif; Vaitheeswaran, G.

2009-01-01

The high-pressure structural behavior of Sr2CrReO6 has been studied experimentally using synchrotron radiation and the diamond anvil cell and theoretically using density functional theory. The experimental zero-pressure bulk modulus is B0=1704GPa and the pressure derivative is B0'=4.71.0. These r...

Igneous Consequence Modeling for the TSPA-SR

International Nuclear Information System (INIS)

McCord, John

2001-01-01

The purpose of this technical report is to develop credible, defendable, substantiated models for the consequences of igneous activity for the TSPA-SR Model. The effort will build on the TSPA-VA and improve the quality of scenarios and depth of the technical basis underlying disruptive events modeling. Computational models for both volcanic eruptive releases (this is an event that results in ash containing waste being ejected from Yucca Mountain) and igneous intrusion groundwater releases (this is an event that reaches the repository level, impacts the waste packages, and produces releases from waste packages damaged by igneous activity) will be included directly in the TSPA calculations as part of the TSPA-SR Model. This Analysis Model Report (AMR) is limited to development of the conceptual models for these two scenarios. The mathematical implementation of these conceptual models will be done within the TSPA-SR Model. Thus, this AMR will not include any model results or sensitivity analyses. Calculation of any doses resulting from igneous releases will also be done within the TSPA-SR model, as will the probabilistic weighting of these doses. Calculation and analysis of the TSPA-SR Model results for igneous disruption are, therefore, outside the scope of this activity. The reason for not running the mathematical models as part of this AMR is that the models are integrated within the TSPA-SR model and, thus, any model simulations and the corresponding results are out of the scope of this AMR. The scope of this work as defined in the development plan (CRWMS M and O 2000j) involves using data that has been extracted from existing sources to design and support the TSPA-SR models for the transport of radionuclides following igneous disruption of the repository. The development plan states ''applications of the code in this analysis will be limited to testing of the code and sensitivity analyses during analysis design.'' In contrast to the development plan, the ASHPLUME

Separation of 90Sr from Purex high level waste and development of a 90Sr-90Y generator

International Nuclear Information System (INIS)

Ramanujam, A.; Dhami, P.S.; Chitnis, R.R.; Achuthan, P.V.; Kannan, R.; Gopalakrishnan, V.; Balu, K.

2000-04-01

90 Y (T 1/2 =64.2 h) finds several applications in nuclear medicine. It is formed from the decay of 90 Sr which has a long half-life of 28.8 years. 90 Sr can be used as a long-lasting source for the production of carrier-free 90 Y. 90 Sr itself is abundantly available in high level waste (HLW) of PUREX origin. The present studies deal with the separation of pure 90 Sr from HLW and the subsequent separation of 90 Y from 90 Sr. Actinides and some of the fission products like lanthanides, zirconium, molybdenum and cesium were first removed from the HLW using methods based on solvent extraction and ion-exchange studied earlier in our laboratory. The resulting waste solution was used as a feed for the present process. The separation of 90 Sr from HLW was based on radiochemical method which involved a repeated scavenging with ferric hydroxide followed by strontium carbonate precipitation. The separation of 90 Y from 90 Sr was achieved by membrane separation technique. A compact generator is developed for this separation using a commercially available polytetrafluoroethylene (PTFE) membrane, impregnated with indigenously synthesised 2-ethylhexyl 2-ethylhexyl phosphonic acid (KSM-17). Generator system overcomes the drawbacks associated with conventional solvent extraction and ion-exchange based generators. The product is in chloride form and is suitable for complexation studies. After gaining an operating experience of ∼3 years in generating carrier-free 90 Y at 2 mCi level for initial studies in radiotherapeutic applications, the process was scaled up for the production of about 12 mCi of 90 Y to be used for animal studies before its application to patients. Radiochemical and chemical purity of the product was critically assayed by radiometry, ICP-AES, etc. The process is amenable for further scaling up. (author)

FEP report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Skagius, Kristina [Kemakta Konsult AB, Stockholm (Sweden)

2006-11-15

This report documents the analysis and processing of features, events and processes, FEPs, that has been carried out within the safety assessment SR-Can, and forms an important part of the reporting of the project. The SR-Can project is a preparatory stage for the SR-Site assessment, and the report from that project will be used in support of SKB's application to build a final repository. The overall objective of the FEP analysis and processing included development of a database of features, events and processes, an SKB FEP database, in a format that facilitates both a systematic analysis of FEPs and documentation of that FEP analysis, as well as facilitating revisions and updates to be made in connection with new safety assessments. The overall objective also extended to the development of procedures for such a systematic FEP analysis as well as the application of those procedures in order to establish an SR-Can FEP catalogue within the framework of the SKB FEP database. The work started by implementing the content of the SR 97 Process Report into a database format suitable for import and processing of FEP information from other sources. The SR 97 version of the database was systematically audited against the NEA database with Project FEPs, version 1.2. In addition, an earlier audit of the SR 97 process report against the interaction matrices developed for a deep repository of the KBS-3 type was revisited and updated. Relevant FEPs identified through the audit process were sorted into three main categories i) FEPs related to the initial states of the repository system, ii) FEPs related to internal processes of the repository system, and iii) FEPs related to external impacts on the repository system. This resulted in additions to the SR 97 list of processes and to the lists of initial state FEPs and external factors to be addressed in further processing. The further processing of the initial state FEPs revealed that those FEPs that are not covered by the

Comparative study of potentially J{sub eff} = 0 ground state iridium(V) in SrLaNiIrO{sub 6}, SrLaMgIrO{sub 6}, and SrLaZnIrO{sub 6}

Energy Technology Data Exchange (ETDEWEB)

Wolff, Klaus K.; Agrestini, Stefano; Tjeng, Liu Hao [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Tanaka, Arata [Department of Quantum Matter, AdSM, Hiroshima University, Higashi-Hiroshima (Japan); Jansen, Martin [Max Planck Institute for Chemical Physics of Solids, Dresden (Germany); Max Planck Institute for Solid State Research, Stuttgart (Germany)

2017-12-13

A series of polycrystalline double perovskites SrLaBIrO{sub 6} (B = Ni, Mg, Zn) containing Ir{sup 5+} (5d{sup 4}) was synthesized by solid state reactions, and structural, magnetic and electronic properties were investigated. The isotypic fully ordered double perovskites crystallize in space group P2{sub 1}/n and show semiconducting behavior with estimated bandgaps of approximately 0.2 eV for SrLaNiIrO{sub 6} and SrLaZnIrO{sub 6}, and 0.4 eV for SrLaMgIrO{sub 6}. SrLaNiIrO{sub 6} is an antiferromagnet with a Neel temperature of 74 K (μ{sub eff} = 3.3 μ{sub B}, θ{sub W} = -90 K), whereas SrLaMgIrO{sub 6} and SrLaZnIrO{sub 6} are weakly paramagnetic. All title compounds exhibit a temperature-independent contribution to the measured magnetic susceptibility, which supports the notion for a van-Vleck-type response originating from the Ir{sup 5+} (5d{sup 4}, J{sub eff} = 0) ions. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Renewable Energy Policy Fact sheet - Ireland

International Nuclear Information System (INIS)

2017-09-01

The EurObserv'ER policy profiles give a snapshot of the renewable energy policy in the EU Member States. With Ireland's current 'trajectory' of renewable energy growth, it is likely to slightly fall short of its 2020 nationally binding renewable energy target. Ireland initiated a 'moratorium' on its REFIT (Renewable Energy Feed-in Tariff) support scheme in December 2015, with the aim of introducing a revised scheme in 2017 in line with market developments. Grants and tax relief remain in place for renewable heat promotion. An Offshore Renewable Energy Development Plan (OREDP) was introduced in 2014, which sets out Government policy in relation to the sustainable development of Ireland's abundant offshore renewable energy resource

renewables 2011 - Global status report

International Nuclear Information System (INIS)

Sawin, Janet L.; Martinot, Eric; Barnes, Douglas; Martinot, Eric; McCrone, Angus; Roussell, Jodie; Sawin, Janet L.; Sims, Ralph; Sonntag-O'Brien, Virginia; Adib, Rana; Skeen, Jonathan; Musolino, Evan; Riahi, Lily; Mastny, Lisa

2011-01-01

Changes in renewable energy markets, investments, industries, and policies have been so rapid in recent years that perceptions of the status of renewable energy can lag years behind the reality. This report captures that reality and provides a unique overview of renewable energy worldwide as of early 2011. The report covers both current status and key trends; by design, it does not provide analysis or forecast the future. Global energy consumption rebounded in 2010 after an overall downturn in 2009. Renewable energy, which experienced no downturn in 2009, continued to grow strongly in all end-use sectors - power, heat and transport - and supplied an estimated 16% of global final energy consumption. Renewable energy accounted for approximately half of the estimated 194 gigawatts (GW) of new electric capacity added globally during the year. Renewables delivered close to 20% of global electricity supply in 2010, and by early 2011 they comprised one quarter of global power capacity from all sources. In several countries, renewables represent a rapidly growing share of total energy supply, including heat and transport

System of Sr(NO sub 2 ) sub 2 -Sr(OH) sub 2 -H sub 2 O at 25 deg C. Sistema Sr(NO sub 2 ) sub 2 -H sub 2 O pri 25 grad C

Energy Technology Data Exchange (ETDEWEB)

Popova, T B; Berdyukova, V A; Khutsistova, F M [Kalmytskij Gosudarstvennyj Univ., Ehlista (USSR) Rostovskij-na-Donu Gosudarstvennyj Univ., Rostov-na-Donu (USSR)

1990-02-01

Sr(NO{sub 2}){sub 2}-Sr(OH){sub 2}-H{sub 2}O system was investigated by the methods of solubility, density, viscosity, electric conductivity and refractometry. It was established that its compoments form the compound 4Sr(NO{sub 2}){sub 2}xSr(OH){sub 2}x8H{sub 2}O. The compound was separated from solution; its density, decomposition temperature were determined; IR spectra and X-ray patterns of prepared and initial compounds were obtained.

ELNES study of chemical solution deposited SrO(SrTiO3)n Ruddlesden-Popper films: Experiment and simulation

International Nuclear Information System (INIS)

Riedl, T.; Gemming, T.; Weissbach, T.; Seifert, G.; Gutmann, E.; Zschornak, M.; Meyer, D.C.; Gemming, S.

2009-01-01

This article analyzes electron energy-loss near-edge fine structures of the SrO(SrTiO 3 ) n=1 Ruddlesden-Popper system and of the parent compounds SrTiO 3 and SrO by comparison with first principles calculations. For that, the fine structures of chemical solution deposited Ruddlesden-Popper films have been experimentally recorded by means of transmission electron microscopy. Moreover, density of states computations using an all-electron density-functional code have been performed. It is shown that the appearance and shape of the experimental O-K and Ti-L 2,3 fine structure features result from the crystallography-dependent electronic structure of the investigated oxides, which display technologically interesting dielectric as well as lattice-structural properties.

Estimation of the magnetic entropy change by means of Landau theory and phenomenological model in La0.6Ca0.2 Sr0.2MnO3/Sb2O3 ceramic composites

Science.gov (United States)

Nasri, M.; Dhahri, E.; Hlil, E. K.

2018-06-01

In this paper, magnetocaloric properties of La0.6Ca0.2Sr0.2MnO3/Sb2O3 oxides have been investigated. The composite samples were prepared using the conventional solid-state reaction method. The second-order phase transition can be testified with the positive slope in Arrott plots. An excellent agreement has been found between the -ΔSM values estimated by Landau theory and those obtained using the classical Maxwell relation. The field dependence of the magnetic entropy change analysis shows a power law dependence,|ΔSM|≈Hn , with n(TC) = 0.65. Moreover, the scaling analysis of magnetic entropy change exhibits that ΔSM(T) curves collapse into a single universal curve, indicating that the observed paramagnetic to ferromagnetic phase transition is an authentic second-order phase transition. The maximum value of magnetic entropy change of composites is found to decrease slightly with the further increasing of Sb2O3 concentration. A phenomenological model was used to predict magnetocaloric properties of La0.6Ca0.2Sr0.2MnO3/Sb2O3 composites. The theoretical calculations are compared with the available experimental data.

Unforeseen consequences of dedicated renewable energy transmission: Potential implications for renewable electricity development

Energy Technology Data Exchange (ETDEWEB)

Bezdek, Roger

2010-09-15

Renewable electricity generation requires expansion of electricity transmission, and the U.S. is planning to build a 'green' transmission lines restricted to renewable electricity. However, local jurisdictions are resisting this unless the transmission serves local constituents and existing power plants. This paper finds that if such transmission is built and local access allowed, then the major beneficiaries may be existing power plants. Their access to added transmission could enable them to sell electric power at rates against which renewables cannot compete. These issues must be addressed if large additions of new transmission lines are to facilitate expansion of renewable electricity generation worldwide.

Development of 90Sr-90Y generators

International Nuclear Information System (INIS)

Barrio, Graciela

2007-01-01

Yttrium-90 is a radioisotope of great interest in the field of Nuclear Medicine. It is considered one of the most important and most used radionuclides for radioimmunotherapeutical applications, especially promising for the treatment of certain types of cancer. Another important application of 90 Y is radio synovectomy. This radionuclide has a half-life of 64 hours, emits long range beta particles (maximum energy of 2.3 MeV) and decays, without intermediate nuclides, to a stable daughter. 90 Y may be obtained carrier-free, generated by the decay of its parent 90 Sr (half-life=28 years). 90 Sr is a product from uranium fission, and due to its long half-life, can be indefinitely used, which is certainly advantageous. It is present in great amounts, and needs to be processed and purified in order to be used as raw material for the generators. Generators of 90 Sr- 90 Y may thus be used during various months, due to 90 Sr long half-life. Several methods for the separation of 90 Y from 90 Sr by solvent extraction and ion exchange have been reported in literature. Thanks to its simplicity, ion exchange techniques have been more commonly used for this generator system. The main objective of this work was to develop a methodology for the preparation of 90 Sr- 90 Y generators, using cationic exchange resins. In such method, 90 Sr is strongly adsorbed in the resin and 90 Y is eluted by a 0.003 M EDTA solution. According to the quality control carried out, results showed that elution yields are greater than 65%, thus confirming the efficiency of the separation method used.

Possible two-stage 87Sr evolution in the Stockdale Rhyolite

International Nuclear Information System (INIS)

Compston, W.; McDougall, I.; Wyborn, D.

1982-01-01

The Rb-Sr total-rock data for the Stockdale Rhyolite, of significance for the Palaeozoic time scale, are more scattered about a single-stage isochron than expected from experimental error. Two-stage 87 Sr evolution for several of the samples is explored to explain this, as an alternative to variation in the initial 87 Sr/ 86 Sr which is customarily used in single-stage dating models. The deletion of certain samples having very high Rb/Sr removes most of the excess scatter and leads to an estimate of 430 +- 7 m.y. for the age of extrusion. There is a younger alignment of Rb-Sr data within each sampling site at 412 +- 7 m.y. We suggest that the Stockdale Rhyolite is at least 430 m.y. old, that its original range in Rb/Sr was smaller than now observed, and that it experienced a net loss in Sr during later hydrothermal alteration at ca. 412 m.y. (orig.)

Determination of the electrostatic potential distribution in Pt/Fe:SrTiO3/Nb:SrTiO3 thin-film structures by electron holography

Science.gov (United States)

Marchewka, Astrid; Cooper, David; Lenser, Christian; Menzel, Stephan; Du, Hongchu; Dittmann, Regina; Dunin-Borkowski, Rafal E.; Waser, Rainer

2014-11-01

We determined the electrostatic potential distribution in pristine Pt/Fe:SrTiO3/Nb:SrTiO3 structures by electron holography experiments, revealing the existence of a depletion layer extending into the Nb-doped bottom electrode. Simulations of potential profiles in metal-insulator-metal structures were conducted assuming different types and distributions of dopants. It is found that the presence of acceptor-type dopant concentrations at the Fe:SrTiO3/Nb:SrTiO3 interface with a donor-doped insulating layer provides a good match to the measured profile. Such acceptor-type interface concentrations may be associated with Sr vacancies on the Nb:SrTiO3 side of the bottom interface.

Assessing Covariation of Holocene Monsoon Intensity and Local Moisture Conditions in Eastern and Southwestern Amazon Basin Using Speleothem δ18O and 87Sr/86Sr Values

Science.gov (United States)

Ward, B. M.; Wong, C. I.; Novello, V. F.; Silva, L.; McGee, D.; Cheng, H.; Wang, X.; Edwards, R. L.; Cruz, F. W., Sr.; Santos, R. V.

2017-12-01

δ18O records from South America offer insight into past variability of the South American Monsoon System (SAMS). Potential, however, for understanding local moisture conditions is limited as precipitation δ18O is strongly influenced by regional climate dynamics. Here we create Holocene speleothem 87Sr/86Sr records at 200-yr resolution using TIMS methods in the Center for Isotope Geochemistry at Boston College to complement existing Holocene δ18O speleothem records and investigate local moisture conditions above caves located in the eastern Amazon Basin (PAR - 4°S, 55°W) and southwestern Brazil (JAR - 21°S, 56°W). Speleothem 87Sr/86Sr variability is interpreted to reflect differences in the extent of water-rock interaction due to differences in infiltration rates under wet and dry conditions. Drier conditions promote longer residence time, enhanced water-rock interaction, and greater evolution of dripwater 87Sr/86Sr values from an initial isotopic signature acquired from the soil to the signature of the cave host rock. PAR speleothem 87Sr/86Sr values range from 0.71024 to 0.71067 and are bracketed by soil (0.71710 to 0.70956) and bedrock (0.70852 to 0.70899) values. JAR speleothem 87Sr/86Sr values range from 0.71216 to 0.71539 and are greater than bedrock values (0.70825 to 0.71219), although some speleothem values exceed the single analysis conducted of the soil isotopic composition (0.71473). JAR speleothem 87Sr/86Sr values increase from the early to mid Holocene, consistent with increase in local moisture availability associated with intensification of the SAMS suggested by decreasing δ18O values in many records from the region. Speleothem 87Sr/86Sr values at JAR decrease from the mid to late Holocene, consistent with an increase in δ18O values at PAR that suggest a decline in monsoon intensity. 87Sr/86Sr variability at JAR, however, is positively correlated with the δ18O record. Preliminary 87Sr/86Sr results from PAR are only broadly consistent with

2010 Renewable Energy Data Book (Book)

Energy Technology Data Exchange (ETDEWEB)

Gelman, R.

2011-10-01

This Renewable Energy Data Book for 2010 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar energy, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investments.

2013 Renewable Energy Data Book (Book)

Energy Technology Data Exchange (ETDEWEB)

Esterly, S.

2014-12-01

This Renewable Energy Data Book for 2013 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investment.

2011 Renewable Energy Data Book (Book)

Energy Technology Data Exchange (ETDEWEB)

Gelman, R.

2012-10-01

This Renewable Energy Data Book for 2011 provides facts and figures on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar energy, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investments.

The value of renewables

International Nuclear Information System (INIS)

Koch, H.J.

2001-01-01

The article extols the virtues of renewable energy sources. Based largely on the outcome of an IAE meeting in May 2001, the author has outlined an approach for accelerating the development of renewables. The article quotes several statements made by the IAE with respect to the need for a secure supply of affordable energy, sustainable development, diversification, the value of renewables and challenges confronting developers of renewables. The article is presented under the sub-headings of: (i) harnessing energy market forces; (ii) understanding costs in the context of diversification; (iii) economic performance; (iv) environmental protection; (v) an IAE action plan and (vi) conclusions. The author was once the IAE's director for energy efficiency, technology and R and D

Preparation of Sr2(MgMo)1-xRuxO6 ceramics for use in a solid oxide fuel cell anode

International Nuclear Information System (INIS)

Bezerra, Matheus Eiji Ohno; Florio, Daniel Zanetti de; Fonseca, Fabio Coral

2016-01-01

Full text: Solid Oxide Fuel Cells are the most efficient devices known for the direct conversion of fuels into electric energy. Such devices have advanced steadily and are already available for specific applications such as portable power and residential stationary generation. The main objective of this work is the development of anodes for SOFC operating directly with renewable fuels, without the addition of water and using strategic fuels such as ethanol and natural gas. Specifically, a family of mixed ionic-electronic compounds has been investigated: the double perovskites with compositions Sr 2 (MgMo) 1-x Ru x O 6 with x = 0; 1; 2; 5; 10 e 20 at.%. This material has been synthesized by polymeric precursor method. The resins were prepared by combining stoichiometric amounts of the starting solutions. The resulting solution was heated treated under magnetic stirring. The thermal decomposition of the polymeric resin was studied by means of simultaneous thermogravimetric and differential scanning calorimetry up to 1500 °C with heating and cooling rates of 10 °/min in Ar. The thermal decomposition result shows mass loss up to, approximately, 900 °C. However X-ray diffraction analyses of the powder heat treated at 900 °C and 1200 °C presents a considerable content of an undesiderate phase (SrMoO 4 ). According to the literature for similar compounds a thermal treatment under reduction conditions could be necessary to obtain the double perovskites single phase. After this treatment the material will be characterized regarding its electrical properties. The expected results will contribute to advance both the understanding of the mixed ionic electronic ceramics and the SOFC technology using renewable fuels. (author)

ACTH Regulation of Adrenal SR-B1

Directory of Open Access Journals (Sweden)

Wen-Jun eShen

2016-05-01

Full Text Available The adrenal gland is one of the prominent sites for steroid hormone synthesis. Lipoprotein-derived cholesterol esters delivered via scavenger receptor, class B type 1 (SR-B1 constitute the dominant source of cholesterol for steroidogenesis, particularly in rodents. ACTH stimulates steroidogenesis through downstream actions on multiple components involved in steroidogenesis. Both acute and chronic ACTH treatment can modulate SR-B1 function including its transcription, its post transcriptional stability, its phosphorylation and dimerization status, as well as its interaction with other protein partners; all of which result in changes in the ability of SR-B1 to mediate HDL-cholesterol ester uptake and the supply of cholesterol for conversion to steroids. Here we provide a review of the recent findings on the regulation of adrenal SR-B1 function by ACTH.

Rapid determination of {sup 90}Sr in urine samples using AnaLig Sr-01

Energy Technology Data Exchange (ETDEWEB)

Bilohuscin, J.; Dulanska, S.; Gardonova, V. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra jadrovej chemie, 84215 Bratislava (Slovakia)

2013-04-16

This work describes the use of IBC's AnaLig Sr-01 molecular recognition technology product to effectively and selectively pre-concentrate, separate and recover strontium from urine samples. This method uses two-stage columns separation consisting of two different commercial products Eichrom's Pre-filter Material and AnaLig Sr-01 column from IBC Advanced Technologies. This method does not involve co-precipitation of strontium as phosphates and oxalates from urine samples. The new rapid method separates strontium-90 with high chemical recovery (authors)

Development of an on-line flow injection Sr/matrix separation method for accurate, high-throughput determination of Sr isotope ratios by multiple collector-inductively coupled plasma-mass spectrometry.

Science.gov (United States)

Galler, Patrick; Limbeck, Andreas; Boulyga, Sergei F; Stingeder, Gerhard; Hirata, Takafumi; Prohaska, Thomas

2007-07-01

This work introduces a newly developed on-line flow injection (FI) Sr/Rb separation method as an alternative to the common, manual Sr/matrix batch separation procedure, since total analysis time is often limited by sample preparation despite the fast rate of data acquisition possible by inductively coupled plasma-mass spectrometers (ICPMS). Separation columns containing approximately 100 muL of Sr-specific resin were used for on-line FI Sr/matrix separation with subsequent determination of (87)Sr/(86)Sr isotope ratios by multiple collector ICPMS. The occurrence of memory effects exhibited by the Sr-specific resin, a major restriction to the repetitive use of this costly material, could successfully be overcome. The method was fully validated by means of certified reference materials. A set of two biological and six geological Sr- and Rb-bearing samples was successfully characterized for its (87)Sr/(86)Sr isotope ratios with precisions of 0.01-0.04% 2 RSD (n = 5-10). Based on our measurements we suggest (87)Sr/(86)Sr isotope ratios of 0.713 15 +/- 0.000 16 (2 SD) and 0.709 31 +/- 0.000 06 (2 SD) for the NIST SRM 1400 bone ash and the NIST SRM 1486 bone meal, respectively. Measured (87)Sr/(86)Sr isotope ratios for five basalt samples are in excellent agreement with published data with deviations from the published value ranging from 0 to 0.03%. A mica sample with a Rb/Sr ratio of approximately 1 was successfully characterized for its (87)Sr/(86)Sr isotope signature to be 0.718 24 +/- 0.000 29 (2 SD) by the proposed method. Synthetic samples with Rb/Sr ratios of up to 10/1 could successfully be measured without significant interferences on mass 87, which would otherwise bias the accuracy and uncertainty of the obtained data.

Damn renewable energies

International Nuclear Information System (INIS)

Gay, Michel

2017-01-01

In this book, the author describes how renewable energies have been developed in a way he considers as scandalous, whereas they are a technical, financial and ecological dead end. He also explains how ecologists (notably the ADEME) manipulate figures to make believe that these energies could be an answer to the needs of France, of Europe and of humanity. In a first chapter, he criticises the influence of a so-called green ideology on the design of energy transition. In the second one, he denounces twelve tales about energy transition. In the next chapters, he denounces the sham of renewable energies, and finally tells some unfortunate renewable experiments

Effect of Flowing Water on Sr Sorption Changes of Hydrous Sodium Titanate

Directory of Open Access Journals (Sweden)

Youko Takahatake

2017-12-01

Full Text Available Radioactive contaminated water has been generated at the Fukushima Daiichi Nuclear Power station (F1NPS. Hydrous sodium titanate (SrTreat® is able to remove radioactive Strontium (Sr from this water. Knowing the amount of radioactive nuclides in the used as-received SrTreat® is important for effective disposal and deposition of the F1NPS waste. This study investigated changes in the ability of SrTreat® to sorb Sr, and to understand the causes of changes in the sorbing. An investigation of the Sr sorption ability of SrTreat® is important for calculating the initial radioactive inventory of used SrTreat®. This study carries out Sr sorption studies with acid-base titrations and X-ray photoelectron spectroscopy (XPS to characterize the properties. After exposure to simulated treated water for 99 h, the surface structure of the SrTreat® was changed, and the percentage of sorbed Sr and the buffer capacity for protons decreased. When the amount of radioactive nuclides contained in the used SrTreat® is calculated from the sorption data of the as-received SrTreat®, the radioactive Sr content will be overestimated with a concomitant increase in the deposition and disposal costs of the used SrTreat®.

Alaska's renewable energy potential.

Energy Technology Data Exchange (ETDEWEB)

2009-02-01

This paper delivers a brief survey of renewable energy technologies applicable to Alaska's climate, latitude, geography, and geology. We first identify Alaska's natural renewable energy resources and which renewable energy technologies would be most productive. e survey the current state of renewable energy technologies and research efforts within the U.S. and, where appropriate, internationally. We also present information on the current state of Alaska's renewable energy assets, incentives, and commercial enterprises. Finally, we escribe places where research efforts at Sandia National Laboratories could assist the state of Alaska with its renewable energy technology investment efforts.

Renewable energy policy. Into the mainstream

International Nuclear Information System (INIS)

2003-01-01

Renewable energy today is at a critical stage of development: renewable technologies are maturing, and costs for some technologies are in the competitive range. Beyond the energy they produce, renewable energy technologies offer a variety of other benefits towards the achievement of sustainable development goals. This promise has led to all IEA governments to support their greater development. But, while renewables markets are growing strongly, additional steps must be taken to accelerate the achievement of sustainable, large-scale markets. This report by the IEA's Renewable Energy Working Party outlines those steps, and the benefits of moving renewable energy into the mainstream

Thermoelectric and spincaloric properties of epitaxial LaNiO{sub 3}/SrTiO{sub 3} superlattices from first principles

Energy Technology Data Exchange (ETDEWEB)

Geisler, Benjamin [FRM II, Technische Universitaet Muenchen, Garching (Germany); Fakultaet fuer Physik, Universitaet Duisburg-Essen, Duisburg (Germany); Blanca-Romero, Ariadna [Imperial College, London (United Kingdom); Pentcheva, Rossitza [Fakultaet fuer Physik, Universitaet Duisburg-Essen, Duisburg (Germany)

2016-07-01

Modern layer-by-layer fabrication techniques make it possible to grow epitaxial oxide superlattices with atomic precision. By combining accurate DFT+U calculations to determine the atomic and electronic structure and Boltzmann transport theory we show how a targeted design of the interface composition can be used to optimize the thermoelectric and/or spincaloric properties of LaNiO{sub 3}/SrTiO{sub 3}(001) superlattices. A TiO{sub 2}/LaO interface induces n-type doping, and a (potentially highly spin-polarized) charge current arises solely in-plane in the NiO{sub 2} layers. The out-of-plane resistance is high, since the SrTiO{sub 3} layers act as tunneling barriers. In contrast, a NiO{sub 2}/SrO interface leads to p-type doping. In this case, also the valence band of SrTiO{sub 3} contributes to the transmission, thereby reducing the out-of-plane resistance significantly. Besides this doping effect we find that the interface composition influences the electronic band structure, which leads to a nontrivial behavior of the Seebeck coefficient. Funding by the DFG within TRR 80 (G3 and G8) is acknowledged.

Atomically resolved spectroscopic study of Sr.sub.2./sub.IrO.sub.4./sub.: Experiment and theory

Czech Academy of Sciences Publication Activity Database

Li, Q.; Cao, G.; Okamoto, S.; Yi, J.; Lin, W.; Sales, B.C.; Yan, J.; Arita, R.; Kuneš, Jan; Kozhevnikov, A.V.; Eguiluz, A.G.; Imada, M.; Gai, Z.; Pan, M.; Mandrus, D.G.

2013-01-01

Roč. 3, OCT (2013), s. 1-7 ISSN 2045-2322 R&D Projects: GA ČR GA13-25251S Institutional support: RVO:68378271 Keywords : Sr 2 IrO 4 * scanning tunneling microscopy * Mott insulator * Slater insulator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 5.078, year: 2013 http://www.nature.com/srep/2013/131029/srep03073/full/srep03073.html

Strong violet-blue light photoluminescence emission at room temperature in SrZrO3: Joint experimental and theoretical study

International Nuclear Information System (INIS)

Longo, V.M.; Cavalcante, L.S.; Erlo, R.; Mastelaro, V.R.; Figueiredo, A.T. de; Sambrano, J.R.; Lazaro, S. de; Freitas, A.Z.; Gomes, L.; Vieira, N.D.; Varela, J.A.; Longo, Elson

2008-01-01

Ultrafine ordered and disordered SrZrO 3 powders were prepared by the polymeric precursor method. The structural evolution from structural disorder to order was monitored by X-ray diffraction and X-ray absorption near-edge spectroscopy. Complex cluster vacancies [ZrO 5 .V O Z ]and[SrO 11 .V O Z ] (where V O Z =V O X , V O · andV O ·· ) were proposed for disordered powders. The intense violet-blue light photoluminescence emission measured at room temperature in the disordered powders was attributed to complex cluster vacancies. High-level quantum mechanical calculations within the density functional theory framework were used to interpret the experimental results

Highly-efficient mid-infrared CW laser operation in a lightly-doped 3 at.% Er:SrF2 single crystal.

Science.gov (United States)

Su, Liangbi; Guo, Xinsheng; Jiang, Dapeng; Wu, Qinghui; Qin, Zhipeng; Xie, Guoqiang

2018-03-05

3 at.% Er:SrF 2 laser crystals with high optical quality were successfully grown using the temperature gradient technique (TGT). The intense mid-infrared emission was observed around 2.7 μm with excitation by a 970 nm LD. Based on the Judd-Ofelt theory, the emission cross-sections of the 4 I 13/2 - 4 I 11/2 transition were calculated by using the Fuchtbauer-Ladenburg (FL) method. Efficient continuous-wave laser operation at 2.8 µm was achieved with the lightly-doped 3 at.% Er:SrF 2 crystal pumped by a 970 nm laser diode. The laser output power reached up to 1.06 W with a maximum slope efficiency of 26%.

Economics of nuclear and renewables

International Nuclear Information System (INIS)

Khatib, Hisham; Difiglio, Carmine

2016-01-01

This paper provides an assessment of the economic challenges faced by both nuclear power and “new” renewable electricity technologies. The assessment reflects the need to incorporate new renewables into power grids and issues faced in dispatching power and their effect on traditional electricity technologies as well as the need for transmission extension and/or grid reinforcement. Wider introduction of smart grids and the likely demise of nuclear in some OECD countries are bound to enhance the future prospects for new renewables. However, their immediate future expansion will depend on continued subsidies, which are becoming difficult to sustain in present economic circumstances. Development of large energy storage facilities and carbon pricing could significantly enhance future renewable energy prospects. Correspondingly, expanding renewable energy, in spite of their popularity with some governments and sections of the public, is likely to face challenges which will slow their present rapid progress. Nuclear is now shied away from in many industrialized countries and having mixed prospects in developing economies. In many instances, it suffers from high initial costs, long lead times and often excessive construction delays. Nuclear power also faces challenging risks – investment as well as regulatory. In contrast to renewables, its share of global energy consumption is declining. - Highlights: •Renewables are increasing their energy share. •Renewables system cost is higher than their production cost. •Nuclear share is not increasing and their costs are not reduced. •Discount rate and subsidies are important in economics of renewables and nuclear.

PEI's perspective on renewable energy development

International Nuclear Information System (INIS)

Brown, B.

2005-01-01

Approximately 7 per cent of Prince Edward Island's (PEI) energy supply is from renewable sources, acquired mainly from biomass. Wind power accounts for 0.5 per cent of electricity production. This paper discussed issues concerning renewable energy developments in PEI, with particular reference to the PEI Renewable Energy Act as well as the PEI energy framework and renewable energy strategy, which was the result of public consultation sessions held in 2003. The results of these sessions indicated that greater development of indigenous renewable energy resources was desired, particularly in wind power. It was also stated that the government should help to advance renewable energy development in the province. Several development opportunities were highlighted, including: wind; biodiesel; ethanol; biomass; bio-gas; and small-scale hydro. The advantages of wind power were reviewed and wind data was presented. The economic and community benefits of renewable energy include local price stability, development opportunities, diversity of fuel type and security of supply. It was noted that renewable energy fully complemented the energy goals of the PEI government. Several strategies were discussed towards the development of renewable energy, including feasibility studies in biogas and biomass generation. The PEI government's commitment towards developing a regulatory framework acknowledging environmental sustainability was re-stated. Objectives include the promotion of renewable energy sources through the establishment of a Renewable Portfolio Standard for electricity; improvements in the economics of small-scale electricity production from renewable resources through the introduction of net metering; decreases in peak demand; enablement of green credits; the designation of areas for large-scale wind developments; and provision of guaranteed prices paid to producers for medium and large-scale renewable energy generators through feed-in tariffs. tabs, figs

Structural, electronic and optical properties of cubic SrTiO{sub 3} and KTaO{sub 3}: Ab initio and GW calculations

Energy Technology Data Exchange (ETDEWEB)

Benrekia, A.R., E-mail: benrekia.ahmed@yahoo.com [Faculty of Science and Technology, University of Medea (Algeria); Benkhettou, N. [Laboratoire des Materiaux Magnetiques, Faculte des Sciences, Universite Djillali Liabes de Sidi Bel Abbes (Algeria); Nassour, A. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisations (CRM2, UMR CNRS 7036) Institut Jean Barriol, Nancy Universite BP 239, Boulevard des Aiguillettes, 54506 Vandoeuvre-les-Nancy (France); Driz, M. [Applied Material Laboratory (AML), Electronics Department, University of Sidi bel Abbes (DZ 22000) (Algeria); Sahnoun, M. [Laboratoire de Physique Quantique de la Matiere et Modelisations Mathematique (LPQ3M), Faculty of Science and Technology,University of Mascara (Algeria); Lebegue, S. [Laboratoire de Cristallographie, Resonance Magnetique et Modelisations (CRM2, UMR CNRS 7036) Institut Jean Barriol, Nancy Universite BP 239, Boulevard des Aiguillettes, 54506 Vandoeuvre-les-Nancy (France)

2012-07-01

We present first-principles VASP calculations of the structural, electronic, vibrational, and optical properties of paraelectric SrTiO{sub 3} and KTaO{sub 3}. The ab initio calculations are performed in the framework of density functional theory with different exchange-correlation potentials. Our calculated lattice parameters, elastic constants, and vibrational frequencies are found to be in good agreement with the available experimental values. Then, the bandstructures are calculated with the GW approximation, and the corresponding band gap is used to obtain the optical properties of SrTiO{sub 3} and KTaO{sub 3}.

Role of Non-Renewable and Renewable Energy for Sustainable Electricity Generation in Malaysia

OpenAIRE

Hussain Ali Bekhet; Nor Hamisham Harun

2016-01-01

The main objective of this paper is to give a comprehensive review of non-renewable energy and renewable energy utilization in Malaysia, including hydropower, solar photovoltaic, biomass and biogas technologies. Malaysia mainly depends on non-renewable energy (natural gas, coal and crude oil) for electricity generation. Therefore, this paper provides a comprehensive review of the energy sector and discusses diversification of electricity generation as a strategy for providing sustainable ener...

2012 Renewable Energy Data Book (Book)

Energy Technology Data Exchange (ETDEWEB)

Gelman, R.

2013-10-01

This Renewable Energy Data Book for 2012 provides facts and figures in a graphical format on energy in general, renewable electricity in the United States, global renewable energy development, wind power, solar power, geothermal power, biopower, hydropower, advanced water power, hydrogen, renewable fuels, and clean energy investment.

Nuclear theory group. Progress report and renewal proposal

International Nuclear Information System (INIS)

1979-01-01

The work discussed covers a broad range of topics in theoretical nuclear and intermediate-energy physics and nuclear astrophysics. Primary emphasis is placed on understanding the underlying nucleon-nucleon and meson-nucleon interactions. The research is categorized as follows: fundamental interactions; intermediate-energy physics; effective interactions, nuclear models and many-body theory; structure of finite nuclei; nuclear astrophysics; heavy-ion physics; and numerical analysis. Page-length summaries of the work are given; completed work has been or will be published. Staff vitas, recent publications, and a proposed budget complete the report

Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

Energy Technology Data Exchange (ETDEWEB)

Aina, Valentina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Bergandi, Loredana, E-mail: loredana.bergandi@unito.it [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy); Lusvardi, Gigliola; Malavasi, Gianluca [Department of Chemical and Geological Sciences, Università di Modena and Reggio Emilia, Via Campi 183, 41125 Modena (Italy); Imrie, Flora E.; Gibson, Iain R. [School of Medical Sciences, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD (United Kingdom); Cerrato, Giuseppina [Department of Chemistry, Università degli Studi di Torino, Via P. Giuria 7, 10125 Torino (Italy); Centre of Excellence NIS (Nanostructured Interfaces and Surface) Università degli Studi di Torino (Italy); INSTM (Italian National Consortium for Materials Science and Technology), UdR Università di Torino (Italy); Ghigo, Dario [Department of Oncology, Università degli Studi di Torino, Via Santena 5/bis, 10126 Torino (Italy)

2013-04-01

A series of Sr-substituted hydroxyapatites (HA), of general formula Ca{sub (10−x)}Sr{sub x}(PO{sub 4}){sub 6}(OH){sub 2}, where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl{sub 2,} in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in

Sr-containing hydroxyapatite: morphologies of HA crystals and bioactivity on osteoblast cells

International Nuclear Information System (INIS)

Aina, Valentina; Bergandi, Loredana; Lusvardi, Gigliola; Malavasi, Gianluca; Imrie, Flora E.; Gibson, Iain R.; Cerrato, Giuseppina; Ghigo, Dario

2013-01-01

A series of Sr-substituted hydroxyapatites (HA), of general formula Ca (10−x) Sr x (PO 4 ) 6 (OH) 2 , where x = 2 and 4, were synthesized by solid state methods and characterized extensively. The reactivity of these materials in cell culture medium was evaluated, and the behavior towards MG-63 osteoblast cells (in terms of cytotoxicity and proliferation assays) was studied. Future in vivo studies will give further insights into the behavior of the materials. A paper by Lagergren et al. (1975), concerning Sr-substituted HA prepared by a solid state method, reports that the presence of Sr in the apatite composition strongly influences the apatite diffraction patterns. Zeglinsky et al. (2012) investigated Sr-substituted HA by ab initio methods and Rietveld analyses and reported changes in the HA unit cell volume and shape due to the Sr addition. To further clarify the role played by the addition of Sr on the physico-chemical properties of these materials we prepared Sr-substituted HA compositions by a solid state method, using different reagents, thermal treatments and a multi-technique approach. Our results indicated that the introduction of Sr at the levels considered here does influence the structure of HA. There is also evidence of a decrease in the crystallinity degree of the materials upon Sr addition. The introduction of increasing amounts of Sr into the HA composition causes a decrease in the specific surface area and an enrichment of Sr-apatite phase at the surface of the samples. Bioactivity tests show that the presence of Sr causes changes in particle size and/or morphology during soaking in MEM solution; on the contrary the morphology of pure HA does not change after 14 days of reaction. The presence of Sr, as Sr-substituted HA and SrCl 2, in cultures of human MG-63 osteoblasts did not produce any cytotoxic effect. In fact, Sr-substituted HA increased the proliferation of osteoblast cells and enhanced cell differentiation: Sr in HA has a positive effect

Rapid Simultaneous Determination of 89Sr and 90Sr in Milk: A Procedure Using Cerenkov and Scintillation Counting

International Nuclear Information System (INIS)

2013-01-01

Since 2004, the IAEA programme related to the terrestrial environment has included activities aimed at developing and testing a set of procedures for the determination of radionuclides in environmental samples. Both 89Sr and 90Sr are fission products that can be, and have been, released to the environment during nuclear explosions and nuclear reactor accidents. Since strontium uptake from milk is an important pathway for incorporation of radioactive strontium into the human body, the rapid and accurate analysis of radioactive strontium isotopes in milk is of crucial importance in emergency situations in order to protect the public from radiation hazards. This report describes a new approach for the rapid determination of 89 Sr and 90Sr in milk using Cerenkov and scintillation counting methods that was tested and validated by the analysis of four spiked milk samples in terms of repeatability, reproducibility and trueness (relative bias) in accordance with ISO guidelines. The report also describes the calculation of the uncertainty budget. This research was proposed in 2007 at the Asia-Pacific regional meeting of the IAEA Analytical Laboratories for the Measurement of Environmental Radioactivity (ALMERA) network. Several ALMERA network laboratories participated in the validation procedure by performing reproducibility tests. The resulting recommended procedure is designed to be of general use to a wide range of laboratories, including those in the ALMERA network. It is expected that this rapid method for determining 89 Sr and 90 Sr in milk will be useful in emergency conditions and for routine environmental monitoring of elevated levels of radioactivity

Effect of SrO content on Zeolite Structure

Science.gov (United States)

Widiarti, N.; Sari, U. S.; Mahatmanti, F. W.; Harjito; Kurniawan, C.; Prasetyoko, D.; Suprapto

2018-04-01

The aims of current studies is to investigate the effect of strontium oxide content (SrO) on synthesized zeolite. Zeolite was synthesized from Tetraethyl orthosilicate (TEOS) as precursors of SiO2 and aluminum isopropoxide (AIP) precursors. The mixture was aged for 3 days and hydrothermally treated for 6 days. The SrO content was added by impregnation method. The products were then characterized using X-Ray Diffraction (XRD), Fourier Transform Infrared (FTIR), and Surface Area Analyzer (SAA). The diffractogram confirmed the formation of Faujasite-like zeolite. However, after the addition of SrO, the crystallinity of zeolite was deformed. The diffractograms shows the amorphous phase of zeolite were decrease as the SrO content is increase. The structural changes was also observed from FTIR spectra which shows the shifting and peak formation. The surface area analysis showed that the increasing loading of SrO/Zeolites reduced the catalyst surface area.

Sr-90 determination in aqueous and soils samples

International Nuclear Information System (INIS)

Gonzalez Sintas, Maria F.; Cerchietti, Maria L.; Arguelles, Maria G.

2009-01-01

The main objective of this paper is to evaluate the method for Sr-90 determination in aqueous sample and soils. Area and Personal Dosimetry laboratory (DPA) determines the presence of Sr-90 by Liquid Scintillation (LSC) by applying method of the double window and corresponding adjustments. Calibration is performed by standard solutions of 90 Sr/ 90 Y, where spectral 90 Sr and 90 Y zones are optimized. The initial treatment of the liquid samples includes the concentration for evaporation, while the solid ones dissolve for microwave and acidic digestion. The separation of the analyte involves a selective chromatographic extraction. An average efficiency for 90 Sr of 77 ± 1 % was obtained; the factor a/b was 0,85 ± 0,01 and recovery of 82 ± 8 %. The resultant MAD was 0,10 Bq/L in aqueous samples and 0,10 Bq/g in solid samples. (author)

Renewable energy progress and biofuels sustainability

Energy Technology Data Exchange (ETDEWEB)

Hamelinck, C.; De Lovinfosse, I.; Koper, M.; Beestermoeller, C.; Nabe, C.; Kimmel, M.; Van den Bos, A.; Yildiz, I.; Harteveld, M. [Ecofys Netherlands, Utrecht (Netherlands); Ragwitz, M.; Steinhilber, S. [Fraunhofer Institut fuer System- und Innovationsforschung ISI, Karlsruhe (Germany); Nysten, J.; Fouquet, D. [Becker Buettner Held BBH, Munich (Germany); Resch, G.; Liebmann, L.; Ortner, A.; Panzer, C. [Energy Economics Group EEG, Vienna University of Technology, Vienna (Austria); Walden, D.; Diaz Chavez, R.; Byers, B.; Petrova, S.; Kunen, E. [Winrock International, Brussels (Belgium); Fischer, G.

2013-03-15

On 27 March 2013, the European Commission published its first Renewable Energy Progress Report under the framework of the 2009 Renewable Energy Directive. Since the adoption of this directive and the introduction of legally binding renewable energy targets, most Member States experienced significant growth in renewable energy consumption. 2010 figures indicate that the EU as a whole is on its trajectory towards the 2020 targets with a renewable energy share of 12.7%. Moreover, in 2010 the majority of Member States already reached their 2011/2012 interim targets set in the Directive. However, as the trajectory grows steeper towards the end, more efforts will still be needed from the Member States in order to reach the 2020 targets. With regard to the EU biofuels and bioliquids sustainability criteria, Member States' implementation of the biofuels scheme is considered too slow. In accordance with the reporting requirements set out in the 2009 Directive on Renewable Energy, every two years the European Commission publishes a Renewable Energy Progress Report. The report assesses Member States' progress in the promotion and use of renewable energy along the trajectory towards the 2020 renewable energy targets. The report also describes the overall renewable energy policy developments in each Member State and their compliance with the measures outlined in the Directive and the National Renewable Energy Action Plans. Moreover, in accordance with the Directive, it reports on the sustainability of biofuels and bioliquids consumed in the EU and the impacts of this consumption. A consortium led by Ecofys was contracted by the European Commission to perform support activities concerning the assessment of progress in renewable energy and sustainability of biofuels.

Renewable energy progress and biofuels sustainability

Energy Technology Data Exchange (ETDEWEB)

Hamelinck, C.; De Lovinfosse, I.; Koper, M.; Beestermoeller, C.; Nabe, C.; Kimmel, M.; Van den Bos, A.; Yildiz, I.; Harteveld, M. [Ecofys Netherlands, Utrecht (Netherlands); Ragwitz, M.; Steinhilber, S. [Fraunhofer Institut fuer System- und Innovationsforschung ISI, Karlsruhe (Germany); Nysten, J.; Fouquet, D. [Becker Buettner Held BBH, Munich (Germany); Resch, G.; Liebmann, L.; Ortner, A.; Panzer, C. [Energy Economics Group EEG, Vienna University of Technology, Vienna (Austria); Walden, D.; Diaz Chavez, R.; Byers, B.; Petrova, S.; Kunen, E. [Winrock International, Brussels (Belgium); Fischer, G.

2013-03-15

On 27 March 2013, the European Commission published its first Renewable Energy Progress Report under the framework of the 2009 Renewable Energy Directive. Since the adoption of this directive and the introduction of legally binding renewable energy targets, most Member States experienced significant growth in renewable energy consumption. 2010 figures indicate that the EU as a whole is on its trajectory towards the 2020 targets with a renewable energy share of 12.7%. Moreover, in 2010 the majority of Member States already reached their 2011/2012 interim targets set in the Directive. However, as the trajectory grows steeper towards the end, more efforts will still be needed from the Member States in order to reach the 2020 targets. With regard to the EU biofuels and bioliquids sustainability criteria, Member States' implementation of the biofuels scheme is considered too slow. In accordance with the reporting requirements set out in the 2009 Directive on Renewable Energy, every two years the European Commission publishes a Renewable Energy Progress Report. The report assesses Member States' progress in the promotion and use of renewable energy along the trajectory towards the 2020 renewable energy targets. The report also describes the overall renewable energy policy developments in each Member State and their compliance with the measures outlined in the Directive and the National Renewable Energy Action Plans. Moreover, in accordance with the Directive, it reports on the sustainability of biofuels and bioliquids consumed in the EU and the impacts of this consumption. A consortium led by Ecofys was contracted by the European Commission to perform support activities concerning the assessment of progress in renewable energy and sustainability of biofuels.

Priority to renewable energies - on the amendment to the renewable energies act

International Nuclear Information System (INIS)

Heller, W.

2003-01-01

The Federal Ministry for the Environment, which has been the competent authority for renewable energies since the 2002 federal election, has presented draft legislation on the accelerated development of renewable energies in the electricity sector. This is to reduce, through internalization, the costs to the national economy arising from power supply, to conserve nature and the environment, avoid conflicts over fossil energy resources, and promote the advanced development of renewable energy technologies. Emphasis is put solely on protection of the climate and of the environment. The way towards sustainable energy supply by taking into account ecological, economic and social aspects is abandoned. The funding rates laid down in legislation are not going to offer major incentives for further plant improvement by technological development. The quantitative goals of this draft legislation onesidedly aimed at electricity production are doubtful. Renewable energies are hardly the right way to replace nuclear power plants operated in the baseload mode. What is missing in the draft legislation, though it would be urgently needed, is a clear time limit on the eligibility of renewable energy plants for subsidizing, as this would counteract the impression of permanent subsidizing. (orig.)

Renewable Electricity Futures Study. Executive Summary

Energy Technology Data Exchange (ETDEWEB)

Mai, T.; Sandor, D.; Wiser, R.; Schneider, T.

2012-12-01

The Renewable Electricity Futures (RE Futures) Study investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. The analysis focused on the sufficiency of the geographically diverse U.S. renewable resources to meet electricity demand over future decades, the hourly operational characteristics of the U.S. grid with high levels of variable wind and solar generation, and the potential implications of deploying high levels of renewables in the future. RE Futures focused on technical aspects of high penetration of renewable electricity; it did not focus on how to achieve such a future through policy or other measures. Given the inherent uncertainties involved with analyzing alternative long-term energy futures as well as the multiple pathways that might be taken to achieve higher levels of renewable electricity supply, RE Futures explored a range of scenarios to investigate and compare the impacts of renewable electricity penetration levels (30%-90%), future technology performance improvements, potential constraints to renewable electricity development, and future electricity demand growth assumptions. RE Futures was led by the National Renewable Energy Laboratory (NREL) and the Massachusetts Institute of Technology (MIT).

Renewables 2010 - Global status report

International Nuclear Information System (INIS)

Sawin, Janet L.; Martinot, Eric; Sonntag-O'Brien, Virginia; McCrone, Angus; Roussell, Jodie; Barnes, Douglas; Flavin, Christopher; Mastny, Lisa; Kraft, Diana; Wang, Shannon; Ellenbeck, Saskia; Ilieva, Lili; Griebenow, Christof; Adib, Rana; Lempp, Philippe; Welker, Bettina

2010-01-01

Changes in renewable energy markets, investments, industries, and policies have been so rapid in recent years that perceptions of the status of renewable energy can lag years behind the reality. This report captures that reality and provides a unique overview of renewable energy worldwide as of early 2010. The report covers both current status and key trends. By design, the report does not provide analysis, discuss current issues, or forecast the future. Many of the trends reflect the increasing significance of renewable energy relative to conventional energy sources (including coal, gas, oil, and nuclear). By 2010, renewable energy had reached a clear tipping point in the context of global energy supply. Renewables comprised fully one quarter of global power capacity from all sources and delivered 18 percent of global electricity supply in 2009. In a number of countries, renewables represent a rapidly growing share of total energy supply-including heat and transport. The share of households worldwide employing solar hot water heating continues to increase and is now estimated at 70 million households. And investment in new renewable power capacity in both 2008 and 2009 represented over half of total global investment in new power generation. Trends reflect strong growth and investment across all market sectors-power generation, heating and cooling, and transport fuels. Grid-connected solar PV has grown by an average of 60 percent every year for the past decade, increasing 100-fold since 2000. During the past five years from 2005 to 2009, consistent high growth year-after-year marked virtually every other renewable technology. During those five years, wind power capacity grew an average of 27 percent annually, solar hot water by 19 percent annually, and ethanol production by 20 percent annually. Biomass and geothermal for power and heat also grew strongly. Much more active policy development during the past several years culminated in a significant policy milestone

Renewable Energy Policy Fact sheet - Romania

International Nuclear Information System (INIS)

2017-07-01

The EurObserv'ER policy profiles give a snapshot of the renewable energy policy in the EU Member States. The promotion of renewable electricity in Romania relies primarily on a renewable quota scheme. Since 2017 the scheme has been closed for new projects. Renewable heating and cooling is promoted through investment subsidies. Renewable energy sources in the transport sector are promoted by a bio-fuels quota scheme and indirectly through a subsidy scheme for the purchase of electric vehicles

Promoting renewable energy technologies

International Nuclear Information System (INIS)

Grenaa Jensen, S.

2004-06-01

Technologies using renewable energy sources are receiving increasing interest from both public authorities and power producing companies, mainly because of the environmental advantages they procure in comparison with conventional energy sources. These technologies can be substitution for conventional energy sources and limit damage to the environment. Furthermore, several of the renewable energy technologies satisfy an increasing political goal of self-sufficiency within energy production. The subject of this thesis is promotion of renewable technologies. The primary goal is to increase understanding on how technological development takes place, and establish a theoretical framework that can assist in the construction of policy strategies including instruments for promotion of renewable energy technologies. Technological development is analysed by through quantitative and qualitative methods. (BA)

Resistance switching in epitaxial SrCoOx thin films

Science.gov (United States)

Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

2014-08-01

We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO2.5) and conducting perovskite (SrCoO3-δ) depending on the oxygen content. The current-voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoOx thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO2.5.

Resistance switching in epitaxial SrCoOx thin films

International Nuclear Information System (INIS)

Tambunan, Octolia T.; Parwanta, Kadek J.; Acharya, Susant K.; Lee, Bo Wha; Jung, Chang Uk; Kim, Yeon Soo; Park, Bae Ho; Jeong, Huiseong; Park, Ji-Yong; Cho, Myung Rae; Park, Yun Daniel; Choi, Woo Seok; Kim, Dong-Wook; Jin, Hyunwoo; Lee, Suyoun; Song, Seul Ji; Kang, Sung-Jin; Kim, Miyoung; Hwang, Cheol Seong

2014-01-01

We observed bipolar switching behavior from an epitaxial strontium cobaltite film grown on a SrTiO 3 (001) substrate. The crystal structure of strontium cobaltite has been known to undergo topotactic phase transformation between two distinct phases: insulating brownmillerite (SrCoO 2.5 ) and conducting perovskite (SrCoO 3−δ ) depending on the oxygen content. The current–voltage characteristics of the strontium cobaltite film showed that it could have a reversible insulator-to-metal transition triggered by electrical bias voltage. We propose that the resistance switching in the SrCoO x thin film could be related to the topotactic phase transformation and the peculiar structure of SrCoO 2.5

Trace determination of 90Sr and 89Sr in environmental samples by collinear resonance ionization spectroscopy

International Nuclear Information System (INIS)

Lantzsch, J.; Bushaw, B. A.; Bystrow, V. A.; Herrmann, G.; Kluge, H.-J.; Niess, S.; Otten, E. W.; Passler, G.; Schwalbach, R.; Schwarz, M.; Stenner, J.; Trautmann, N.; Wendt, K.; Yushkevich, Y. V.; Zimmer, K.

1995-01-01

Collinear resonance ionization spectroscopy has been developed as a sensitive technique for fast trace detection of 90 Sr and 89 Sr in the environment. A detection limit for 90 Sr of 10 7 atoms in the presence of 10 17 atoms in the presence of 10 17 atoms of stable Strontium has been achieved, while the applicability of the method has been demonstrated on real world samples. After collection and chemical separation, strontium is surface ionized, accelerated to 33keV and mass separated. The ions are neutralized and the emerging fast atoms interact with an argon ion laser beam (γ=364 nm) in a quasi-collinear geometry. Optical excitation starts from the long-lived 5s4d 3 D2 state of strontium, which is populated in the charge exchange process, and the fast atoms are selectively excited into the high-lying 5s23f 3 F3 Rydberg state. The Rydberg-atoms are subsequently field-ionized and detected by a channeltron detector after energy selection. The described method was successfully used to determine the 90 Sr-content in air samples collected near Munich during the Chernobyl reactor accident in April 1986

Magneto-caloric and magneto-resistive properties of La{sub 0.67}Ca{sub 0.33-x}Sr{sub x}MnO{sub 3}

Energy Technology Data Exchange (ETDEWEB)

Reves Dinesen, Anders

2004-08-01

This thesis presents results of an experimental investigation of magneto-caloric and magneto-resistive properties of a series of polycrystalline Ca- and Sr-doped lanthanum manganites, La{sub 0.67}Ca{sub 0.33-x}Sr{sub x}MnO{sub 3} (0{<=} x {<=} 0.33), with the perovskite structure. The samples consisted of sintered oxide powders prepared the glycine-nitrate combustion technique. The compounds were ferromagnetic and showed a Curie transition in the temperature range 267370 K (T{sub C} increased with increasing x). An analysis of the structural properties was carried out by means of x-ray diffraction and the Rietveld technique. The variation of the Ca/Sr ratio was found to cause a transition from orthorhombic to rhombohedral symmetry in the composition range 0.110 < x < 0.165. The analysis suggested a strong correlation between structural properties and magnetism, for instance a relationship between the mean MnOMn bond angle and the Curie temperature. The MnOMn bonds mediate ferromagnetism and electrical transport in these materials via the double-exchange mechanism. The magnetocaloric effect of the La{sub 0.67}Ca{sub 0.33-x}Sr{sub x}MnO{sub 3} samples was measured directly and indirectly (by means of magnetization measurements). All the samples showed a magnetocaloric effect in the vicinity of T{sub C}. A model for the mag-netocaloric effect based on Weiss mean field theory and classical theories for heat capacities was developed. The model provided reasonable predictions of the magneto-caloric properties of the samples. The compounds with low Sr content showed a magnetocaloric effect comparable to that of Gadolinium, the prototypical working material for magnetic refrigeration at room temperature. A less comprehensive part of the investigation regarded the magneto-resistive properties of the La{sub 0.67}Ca{sub 0.33-x}Sr{sub x}MnO{sub 3} system. It was found that th polycrystalline nature of the compounds played a decisive role for the magnetotransport properties