WorldWideScience

Sample records for chemically significant energies

  1. Spectroscopic probes of vibrationally excited molecules at chemically significant energies

    Energy Technology Data Exchange (ETDEWEB)

    Rizzo, T.R. [Univ. of Rochester, NY (United States)

    1993-12-01

    This project involves the application of multiple-resonance spectroscopic techniques for investigating energy transfer and dissociation dynamics of highly vibrationally excited molecules. Two major goals of this work are: (1) to provide information on potential energy surfaces of combustion related molecules at chemically significant energies, and (2) to test theoretical modes of unimolecular dissociation rates critically via quantum-state resolved measurements.

  2. Significance of chemical return in nuclear steam generators

    International Nuclear Information System (INIS)

    A reasonable understanding of PWR steam generator corrosion mechanisms such as denting and wastage has been developed, and adequate chemistry control programs defined to obviate the magnitude and effects of these modes of attack. However, relatively unique corrosion attack modes have been encountered at several plants notwithstanding the presence of a reasonable to very good chemistry control program when considered in light of the Steam Generator Owners Group chemistry guidelines. The uniqueness of attack also suggests that parameters not routinely measured or monitored may be playing a significant role. In the authors opinions, the only reasonable method of routinely identifying corrosion accelerating species present in crevices, sludge piles, and deposits in PWR steam generators is by performing detailed chemical return studies during power transients, shutdowns, and long term layups. Although it would be preferable to obtain samples from regions of attack, such samples generally are not available for obvious reasons

  3. Allophane on Mars: Significance for Chemical Weathering and Soil Development

    Science.gov (United States)

    Kraft, M. D.; Rampe, E. B.; Sharp, T. G.; Ming, D. W.; Golden, D. C.; Christensen, P. R.

    2010-12-01

    It has been suggested that allophane or related poorly crystalline aluminosilicates are present on Mars, and that they comprise the high-silica phase detected by the Thermal Emission Spectrometer (TES) in Surface Type 2 materials (Kraft et al., 2003; Michalski et al., 2005). Using new laboratory spectra of allophanic materials, we (Rampe et al., this meeting) have detected allophane on the Martian surface via spectral modeling of TES data. We find that ST2 materials in the Northern Plains are consistent with a significant amount of high-silica allophane-like materials. In addition, we find that allophane may be present in some areas of the ancient highlands (TES Surface Type 1), but spectra of those regions are more consistent with aluminous allophane. The presence of allophane and its chemical variability have important implications for chemical weathering and soil development on Mars. Allophane-like materials are amorphous or poorly crystalline hydrous aluminosilicates formed from chemical weathering of glasses, feldspars, and other silicates (cf. Parfitt, 2009). True allophane is a combination of SiO2, Al2O3 and H2O, where Al:Si ranges from ~0.5-2. Aluminosilicate gels are amorphous and chemically similar to allophane but can have higher SiO2 contents. The presence of allophane indicates low-temperature chemical weathering and provides constraints on alteration conditions, limiting pH to circum-neutral (~4.5-8). Our model results indicate that weathering occurred in the relatively young northern plains of Mars. The high-silica allophane-like material present there implies little silica mobility through the soil column, which suggests that weathering involved small amounts of liquid water, consistent with our previous models of weathering in ice-rich soils (Kraft et al., 2007). The aluminous allophane indicated by our spectral models to be present in the highlands suggest that those regions experienced greater amounts of SiO2 leaching and weathering in those

  4. The significance of energy for the economy

    International Nuclear Information System (INIS)

    The importance of energy for the economy is described here in practical terms. This is meant for the works and workshop manager, maintenance chief, energy specialist, sales staff of industrial and business organisations. The term 'potential for saving energy' is extensively discussed. Statistical research shows a clear connection between energy application and growth of the economy. Fact: a rational use of energy is worth while in many aspects. figs., tabs., 14 refs

  5. Nuclear energy significantly reduces carbon dioxide emissions

    International Nuclear Information System (INIS)

    This article is devoted to nuclear energy, to its acceptability, compatibility and sustainability. Nuclear energy is non-dispensable part of energy sources with vast innovation potential. The safety of nuclear energy, radioactive waste deposition, and prevention of risk from misuse of nuclear material have to be very seriously adjudged and solved. Nuclear energy is one of the ways how to decrease the contamination of atmosphere with carbon dioxide and it solves partially also the problem of global increase of temperature and climate changes. Given are the main factors responsible for the renaissance of nuclear energy. (author)

  6. The significance of feedback control for chemical sensors

    NARCIS (Netherlands)

    Bergveld, P.

    1992-01-01

    The conventional way of applying chemical sensors is in an open-loop configuration. A parameter of the chemical domain, such as a gas or ion concentration, is converted into a parameter of the mechanical or electrical domain, often with non-linear transfer characteristics. The paramagnetic oxygen se

  7. Chemical composition and medicinal significance of Fagonia cretica: a review.

    Science.gov (United States)

    Qureshi, Huma; Asif, Saira; Ahmed, Haroon; Al-Kahtani, Hassan A; Hayat, Khizar

    2016-01-01

    Members of the family Zygophyllaceae are distributed in arid areas of the world and are traditionally used against various health insults ranging from skin lesions to lethal cancer. Fagonia cretica Linn. is a plant having novel compounds responsive in diseases that are still considered as incurable or are curable with serious side effects. Researchers, particularly of the Asian region elaborately studied the chemical composition and pharmacological activities of this plant. But further studies are still required to evaluate this plant in clinical trials in order to save humanity from synthetic chemical drugs yet disputed as 'friends or foe'. PMID:25921950

  8. Significance of chemical recognition cues is context dependent in ants

    DEFF Research Database (Denmark)

    Bos, N.; Guerrieri, F.J.; d'Ettorre, P.

    2010-01-01

    Recognition of group members is of fundamental importance in social animals, allowing individuals to protect resources against intruders and parasites, as well as ensuring social cohesion within the group. In ants and other social insects, social recognition relies on multicomponent chemical sign...... ensures that learning in an appetitive context does not interfere with the crucial task of colony defence. (C) 2010 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved......Recognition of group members is of fundamental importance in social animals, allowing individuals to protect resources against intruders and parasites, as well as ensuring social cohesion within the group. In ants and other social insects, social recognition relies on multicomponent chemical...

  9. Chemical and pharmacological significance of natural guanidines from marine invertebrates.

    Science.gov (United States)

    Ebada, S S; Proksch, P

    2011-03-01

    Natural Guanidines from marine invertebrates represent a group of bioactive secondary metabolites that revealed prominent pharmacological activities such as antimicrobial, antiproliferative, analgesic, and anti-coagulant properties. Acyclovir (Zovirax(®)), the first guanidine-derived pharmaceutical for the treatment of herpes infections since late 1970s, was synthesized based on a marine arabinosyl nucleoside, spongosine. Recently, ziconotide (Prialt(®)), a synthetic form of the marine-derived peptide (ω-conotoxin MVIIA) comprising a guanidine moiety, has been approved for the treatment of chronic pain. This review surveys over 130 compounds of guanidine-containing secondary metabolites from marine invertebrates with emphasis on their pharmacological significance and structure-activity relationships. PMID:21534931

  10. Significant thermal energy reduction in lactic acid production process

    International Nuclear Information System (INIS)

    Lactic acid is widely used as a raw material for the production of biodegradable polymers and in food, chemical and pharmaceutical industries. The global market for lactic acid is expected to reach 259 thousand metric tons by the year 2012. For batch production of lactic acid, the traditional process includes the following steps: (i) esterification of impure lactic acid with methanol in a batch reactor to obtain methyl lactate (ester), (ii) separation of the ester in a batch distillation, (iii) hydrolysis of the ester with water in a batch reactor to produce lactic acid and (iv) separation of lactic acid (in high purity) in a batch distillation. Batch reactive distillation combines the benefit of both batch reactor and batch distillation and enhances conversion and productivity (Taylor and Krishna, 2000 ; Mujtaba and Macchietto, 1997 ). Therefore, the first and the last two steps of the lactic acid production process can be combined together in batch reactive distillation () processes. However, distillation (batch or continuous) is an energy intensive process and consumes large amount of thermal energy (via steam). This paper highlights how significant (over 50%) reduction in thermal energy consumption can be achieved for lactic acid production process by carefully controlling the reflux ratio but without compromising the product specification. In this paper, only the simultaneous hydrolysis of methyl lactate ester and the separation of lactic acid using batch reactive distillation is considered.

  11. Progress of energy system with chemical-looping combustion

    Institute of Scientific and Technical Information of China (English)

    JIN HongGuang; HONG Hui; HAN Tao

    2009-01-01

    Chemical-looping combustion with zero energy penalty of CO2 separation is a significant breakthrough in resolving energy and environment problems for power generation systems. This paper summarizes the research on energy systems with chemical-looping combustion conducted in recent years, discloses the underlying mechanism of energy release of chemical-looping combustion, describes the trends of the key technology development, and presents the proposed chemicaMooping combustion thermal cycles. This paper may provide a new direction to the synthesis of the next-generation energy system compatible with environment.

  12. 76 FR 75794 - Significant New Use Rules on Certain Chemical Substances; Withdrawal of Two Chemical Substances

    Science.gov (United States)

    2011-12-05

    ... notices (PMNs), i.e., rutile, tin zinc, calcium-doped (PMN P-06-36; CAS No. 389623-01-2) and rutile, tin zinc, sodium-doped (PMN P-06-37; CAS No. 389623-07-8). These chemical substances are subject to TSCA... withdrawing the rules issued for rutile, tin zinc, calcium-doped (PMN P-06-36; CAS No. 389623-01-2) and...

  13. Energy conversion technology by chemical processes

    Energy Technology Data Exchange (ETDEWEB)

    Oh, I.W.; Yoon, K.S.; Cho, B.W. [Korea Inst. of Science and Technology, Seoul (Korea, Republic of)] [and others

    1996-12-01

    The sharp increase in energy usage according to the industry development has resulted in deficiency of energy resources and severe pollution problems. Therefore, development of the effective way of energy usage and energy resources of low pollution is needed. Development of the energy conversion technology by chemical processes is also indispensable, which will replace the pollutant-producing and inefficient mechanical energy conversion technologies. Energy conversion technology by chemical processes directly converts chemical energy to electrical one, or converts heat energy to chemical one followed by heat storage. The technology includes batteries, fuel cells, and energy storage system. The are still many problems on performance, safety, and manufacturing of the secondary battery which is highly demanded in electronics, communication, and computer industries. To overcome these problems, key components such as carbon electrode, metal oxide electrode, and solid polymer electrolyte are developed in this study, followed by the fabrication of the lithium secondary battery. Polymer electrolyte fuel cell, as an advanced power generating apparatus with high efficiency, no pollution, and no noise, has many applications such as zero-emission vehicles, on-site power plants, and military purposes. After fabricating the cell components and operating the single cells, the fundamental technologies in polymer electrolyte fuel cell are established in this study. Energy storage technology provides the safe and regular heat energy, irrespective of the change of the heat energy sources, adjusts time gap between consumption and supply, and upgrades and concentrates low grade heat energy. In this study, useful chemical reactions for efficient storage and transport are investigated and the chemical heat storage technology are developed. (author) 41 refs., 90 figs., 20 tabs.

  14. Development of renewable energy in China:significance & strategic objectives

    Institute of Scientific and Technical Information of China (English)

    Du Xiangwan; Huang Qili; Li Junfeng

    2009-01-01

    Based on CAE's research report, this paper illustrates the background and purposes of the development strat-egy research of renewable energy in China, emphasizes the significance of developing renewable energy in China, gives the strategic positions and development objectives of renewable energy in China in the first half of 21st century and con-tributes to green house gas emissions reduction and environmental protection in China.

  15. Estimation of Radiative Efficiency of Chemicals with Potentially Significant Global Warming Potential

    Data.gov (United States)

    U.S. Environmental Protection Agency — The set of commercially available chemical substances in commerce that may have significant global warming potential (GWP) is not well defined. Although there are...

  16. Potential energy surfaces for chemical reactions

    International Nuclear Information System (INIS)

    Research into potential energy surfaces for chemical reactions at Lawrence Berkeley Laboratory during 1976 is described. Topics covered include: the fuzzy interface between surface chemistry catalysis and organometallic chemistry; potential energy surfaces for elementary fluorine hydrogen reactions; structure, energetics, and reactivity of carbenes; and the theory of self-consistent electron pairs

  17. 78 FR 27048 - Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2013-05-09

    ... average), tube ends (open, capped, circular, other), tube width/diameter (measure inner and outer diameters or range), tube length (range) including a description of any deformities found in the tubes... significant new use rules (SNURs) under the Toxic Substances Control Act (TSCA) for 15 chemical...

  18. Fuels and chemicals from biomass using solar thermal energy

    Science.gov (United States)

    Giori, G.; Leitheiser, R.; Wayman, M.

    1981-01-01

    The significant nearer term opportunities for the application of solar thermal energy to the manufacture of fuels and chemicals from biomass are summarized, with some comments on resource availability, market potential and economics. Consideration is given to the production of furfural from agricultural residues, and the role of furfural and its derivatives as a replacement for petrochemicals in the plastics industry.

  19. Thermodynamic chemical energy transfer mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium chemical reactions

    International Nuclear Information System (INIS)

    Chemical energy transfer mechanisms at finite temperature are explored by a chemical energy transfer theory which is capable of investigating various chemical mechanisms of non-equilibrium, quasi-equilibrium, and equilibrium. Gibbs energy fluxes are obtained as a function of chemical potential, time, and displacement. Diffusion, convection, internal convection, and internal equilibrium chemical energy fluxes are demonstrated. The theory reveals that there are chemical energy flux gaps and broken discrete symmetries at the activation chemical potential, time, and displacement. The statistical, thermodynamic theory is the unification of diffusion and internal convection chemical reactions which reduces to the non-equilibrium generalization beyond the quasi-equilibrium theories of migration and diffusion processes. The relationship between kinetic theories of chemical and electrochemical reactions is also explored. The theory is applied to explore non-equilibrium chemical reactions as an illustration. Three variable separation constants indicate particle number constants and play key roles in describing the distinct chemical reaction mechanisms. The kinetics of chemical energy transfer accounts for the four control mechanisms of chemical reactions such as activation, concentration, transition, and film chemical reactions. - Highlights: • Chemical energy transfer theory is proposed for non-, quasi-, and equilibrium. • Gibbs energy fluxes are expressed by chemical potential, time, and displacement. • Relationship between chemical and electrochemical reactions is discussed. • Theory is applied to explore nonequilibrium energy transfer in chemical reactions. • Kinetics of non-equilibrium chemical reactions shows the four control mechanisms

  20. Chemical kinetics study of hydrocarbon regeneration from organic matter in carbonate source rocks and its significance

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In the comparison research of hydrocarbon regeneration, a low maturity carbonate source rock is heated to different temperatures in a gold tube to obtain a series of samples with different maturities. Then, the heated samples, before and after extraction, are subjected to Rock-Eval pyrolysis through a thermal simulation of hydrocarbon regeneration in order to inspect pyrolysis characteristics and probe into the characteristics of the chemical kinetics of each sample. The results indicate that, whether hy- drocarbon regeneration peak is delayed or advanced, the potential of hydrocarbon regeneration is closely related to the expulsion amount and breakdown maturity of primary hydrocarbon generation. After extraction, the average activation energy of artificially maturated samples increases with the in- creasing maturity, but the chemical kinetic properties of un-extracted samples decrease. The calibrated chemical kinetic models that describe extracted and un-extracted samples are applied to the Bohai Bay and the Songliao Basin, and the results indicate that the combination of the two models can explain some contradictory conclusions previously reported. These results also facilitate the quantitative evaluation of the amount of hydrocarbon regeneration by the chemical kinetic method.

  1. Chemical kinetics study of hydrocarbon regeneration from organic matter in carbonate source rocks and its significance

    Institute of Scientific and Technical Information of China (English)

    LU ShuangFang; ZHONG NingNing; XUE HaiTao; PAN ChangChun; LI JiJun; LI HongTao

    2007-01-01

    In the comparison research of hydrocarbon regeneration, a low maturity carbonate source rock is heated to different temperatures in a gold tube to obtain a series of samples with different maturities. Then, the heated samples, before and after extraction, are subjected to Rock-Eval pyrolysis through a thermal simulation of hydrocarbon regeneration in order to inspect pyrolysis characteristics and probe into the characteristics of the chemical kinetics of each sample. The results indicate that, whether hydrocarbon regeneration peak is delayed or advanced, the potential of hydrocarbon regeneration is closely related to the expulsion amount and breakdown maturity of primary hydrocarbon generation. After extraction, the average activation energy of artificially maturated samples increases with the in creasing maturity, but the chemical kinetic properties of un-extracted samples decrease. The calibrated chemical kinetic models that describe extracted and un-extracted samples are applied to the Bohai Bay and the Songliao Basin, and the results indicate that the combination of the two models can explain some contradictory conclusions previously reported. These results also facilitate the quantitative evaluation of the amount of hydrocarbon regeneration by the chemical kinetic method.

  2. The Surface Chemical Composition of Lunar Samples and Its Significance for Optical Properties

    Science.gov (United States)

    Gold, T.; Bilson, E.; Baron, R. L.

    1976-01-01

    The surface iron, titanium, calcium, and silicon concentration in numerous lunar soil and rock samples was determined by Auger electron spectroscopy. All soil samples show a large increase in the iron to oxygen ratio compared with samples of pulverized rock or with results of the bulk chemical analysis. A solar wind simulation experiment using 2 keV energy alpha -particles showed that an ion dose corresponding to approximately 30,000 years of solar wind increased the iron concentration on the surface of the pulverized Apollo 14 rock sample 14310 to the concentration measured in the Apollo 14 soil sample 14163, and the albedo of the pulverized rock decreased from 0.36 to 0.07. The low albedo of the lunar soil is related to the iron + titanium concentration on its surface. A solar wind sputter reduction mechanism is discussed as a possible cause for both the surface chemical and optical properties of the soil.

  3. Systematic Error Estimation for Chemical Reaction Energies

    CERN Document Server

    Simm, Gregor N

    2016-01-01

    For the theoretical understanding of the reactivity of complex chemical systems accurate relative energies between intermediates and transition states are required. Despite its popularity, density functional theory (DFT) often fails to provide sufficiently accurate data, especially for molecules containing transition metals. Due to the huge number of intermediates that need to be studied for all but the simplest chemical processes, DFT is to date the only method that is computationally feasible. Here, we present a Bayesian framework for DFT that allows for error estimation of calculated properties. Since the optimal choice of parameters in present-day density functionals is strongly system dependent, we advocate for a system-focused re-parameterization. While, at first sight, this approach conflicts with the first-principles character of DFT that should make it in principle system independent, we deliberately introduce system dependence because we can then assign a stochastically meaningful error to the syste...

  4. The Educational and Moral Significance of the American Chemical Society's The Chemist's Code of Conduct

    Science.gov (United States)

    Bruton, Samuel V.

    2003-05-01

    While the usefulness of the case study method in teaching research ethics is frequently emphasized, less often noted is the educational value of professional codes of ethics. Much can be gained by having students examine codes and reflect on their significance. This paper argues that codes such as the American Chemical Society‘s The Chemist‘s Code of Conduct are an important supplement to the use of cases and describes one way in which they can be integrated profitably into a class discussion of research ethics.

  5. Increasing significance of advanced physical/chemical processes in the development and application of sustainable wastewater treatment systems

    Institute of Scientific and Technical Information of China (English)

    Wim RULKENS

    2008-01-01

    The awareness of the problem of the scarcity of water of high quality has strongly changed the approach of wastewater treatment. Currently, there is an increasing need for the beneficial reuse of treated wastewater and to recover valuable products and energy from the wastewater. Because microbiological treatment methods are, only to a limited part, able to satisfy these needs, the role and significance of physical/chemical pro-cesses in wastewater treatment are gaining more and more interest. The specific future role and aim of the various physical/chemical treatment processes can be categorized in five groups: improvement of the perform-ance of microbiological treatment processes, achieve-ment of the high quality required for reuse of the effluent, recovery of valuable components and energy from the wastewater for beneficial reuse, desalination of brackish water and seawater, and treatment of con-centrated liquid or solid waste residues produced in a wastewater treatment process. Development of more environmentally sustainable wastewater treatment chains in which physical/chemical processes play a cru-cial role, also requires application of process control and modeling strategies. This is briefly introduced by the elaboration of treatment scenarios for three specific wastewaters.

  6. Minimum Energy Pathways for Chemical Reactions

    Science.gov (United States)

    Walch, S. P.; Langhoff, S. R. (Technical Monitor)

    1995-01-01

    Computed potential energy surfaces are often required for computation of such parameters as rate constants as a function of temperature, product branching ratios, and other detailed properties. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method to obtain accurate energetics, gives useful results for a number of chemically important systems. The talk will focus on a number of applications to reactions leading to NOx and soot formation in hydrocarbon combustion.

  7. Computed potential energy surfaces for chemical reactions

    Science.gov (United States)

    Walch, Stephen P.

    1994-01-01

    Quantum mechanical methods have been used to compute potential energy surfaces for chemical reactions. The reactions studied were among those believed to be important to the NASP and HSR programs and included the recombination of two H atoms with several different third bodies; the reactions in the thermal Zeldovich mechanism; the reactions of H atom with O2, N2, and NO; reactions involved in the thermal De-NO(x) process; and the reaction of CH(squared Pi) with N2 (leading to 'prompt NO'). These potential energy surfaces have been used to compute reaction rate constants and rates of unimolecular decomposition. An additional application was the calculation of transport properties of gases using a semiclassical approximation (and in the case of interactions involving hydrogen inclusion of quantum mechanical effects).

  8. Wavelet Scattering Regression of Quantum Chemical Energies

    CERN Document Server

    Hirn, Matthew; Poilvert, Nicolas

    2016-01-01

    We introduce multiscale invariant dictionaries to estimate quantum chemical energies of organic molecules, from training databases. Molecular energies are invariant to isometric atomic displacements, and are Lipschitz continuous to molecular deformations. Similarly to density functional theory (DFT), the molecule is represented by an electronic density function. A multiscale invariant dictionary is calculated with wavelet scattering invariants. It cascades a first wavelet transform which separates scales, with a second wavelet transform which computes interactions across scales. Sparse scattering regressions give state of the art results over two databases of organic planar molecules. On these databases, the regression error is of the order of the error produced by DFT codes, but at a fraction of the computational cost.

  9. Energy and environmental challenges to chemical engineers

    International Nuclear Information System (INIS)

    The National Research Council's report, Frontiers in Chemical Engineering, was written four years ago. Three high-priority research areas concerned with energy and the environment were identified in the report: in situ processing, liquid fuels for the future, and responsible management of hazardous wastes. As outlined in the recently released National Energy Strategy, in situ processing is viewed by the Department of Energy (DOE) primarily through its use in enhanced oil recovery, and some research is still funded. Industry, driven by the economics of low oil prices, is doing little research on in situ processing but much more on reservoir characterization, a prerequisite to processing. Research on liquid fuels for the future is driven more by environmental concerns now than by energy security concerns. It appears to be wise policy for the future to try to solve the alternative fuel problem as quickly and simply as possible. Otherwise, the nation will find itself with a costly and complex fuel and vehicle system that may have to be changed again in a generation. For the interim, we should look closely at reformulated gasoline followed by compressed natural gas, if necessary. In the long run, vehicle systems based on electricity seem most promising for the middle of the next century. To deliver this technology we need to capitalize on three new high-priority research areas: batteries, fuel cells, and nuclear power. For chemical engineers, future challenges of a different sort will be added to the technical challenges, among them are explaining to a skeptical public the wisdom of proceeding to design the interim system of alternative fuel(s) and to move expeditiously to a final solution

  10. Predictive Maintenance (PdM) Centralization for Significant Energy Savings

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Dale

    2010-09-15

    Cost effective predictive maintenance (PdM) technologies and basic energy calculations can mine energy savings form processes or maintenance activities. Centralizing and packaging this information correctly empowers facility maintenance and reliability professionals to build financial justification and support for strategies and personnel to weather global economic downturns and competition. Attendees will learn how to: Systematically build a 'pilot project' for applying PdM and tracking systems; Break down a typical electrical bill to calculate energy savings; Use return on investment (ROI) calculations to identify the best and highest value options, strategies and tips for substantiating your energy reduction maintenance strategies.

  11. Chemical Nonequilibrium in High Energy Nuclear Collisions

    OpenAIRE

    Letessier, Jean; Rafelski, Johann

    1998-01-01

    Strange particles produced in S-Au/W/Pb 200 A GeV and Pb-Pb 158 A GeV reactions are described invoking final hadronic phase space in thermal equilibrium, but allowing chemical non-equilibrium. Several sets of statistical freeze-out parameters are obtained for each system, invoking different models of dense matter. We show that only when allowing for strange and non-strange flavor abundance non-equilibrium, a statistically significant description of the experimental results is obtained. Physic...

  12. G-protein-Coupled Receptors and Their (Bio Chemical Significance Win 2012 Nobel Prize in Chemistry

    Directory of Open Access Journals (Sweden)

    Hsi-Hsien Lin

    2013-06-01

    Full Text Available G-protein-coupled receptors (GPCRs are seven transmembrane cell surface proteins specialized in cellular communication. These receptors represent a major gateway through which cells convert external cues into intracellular signals and respond with appropriate actions. While the effects of hormones, neurotransmitters, and drugs on cells, tissues, organs, and even whole organisms are well described, the molecular identity of the direct targets and the diverse signaling mechanisms of these biological ligands have been slow and hard to define. The Nobel Prize in Chemistry for the year 2012 acknowledges the importance of GPCRs in these processes, especially for the contribution of Profs Robert J. Lefkowitz and Brian K. Kobilka to the studies of GPCRs. In this brief review, the seminal works accomplished by the two GPCR pioneers are summarized and the (bio chemical significance of GPCRs in health and disease is discussed.

  13. Heterocyclyl linked anilines and benzaldehydes as precursors for biologically significant new chemical entities

    Indian Academy of Sciences (India)

    Raman K Verma; Vijay Kumar; Prithwish Ghosh; Lalit K Wadhwa

    2012-09-01

    Benzylidene and benzyl thiazolidinediones, oxazolidinediones, isoxazolidinediones and their acyclic analogs like alpha alkylthio/alkoxy phenylpropanoic acids, beta-keto esters and tyrosine-based compounds possess broad therapeutic potential in general and as Peroxisome Proliferator Activated Receptors (PPARs) agonists in particular in the management of hyperglycemia and hyperlipidaemia for the treatment of Type 2 Diabetes (T2D). We have synthesised and characterized some novel and suitably substituted heterocyclyl linked benzaldehydes and anilines, which can be easily and very readily derivatized to all the above mentioned classes to generate new chemical entities of broader biological significance. Synthesis of their benzylidene thiazolidinedione and diethyl malonate and also benzyl diethyl malonate and alpha-bromoesters derivatives is reported in some of the cases in the present work.

  14. Closed loop chemical systems for energy storage and transmission (chemical heat pipe). Final report

    Energy Technology Data Exchange (ETDEWEB)

    Vakil, H.B.; Flock, J.W.

    1978-02-01

    The work documents the anlaysis of closed loop chemical systems for energy storage and transmission, commonly referred to as the Chemical Heat Pipe (CHP). Among the various chemical reaction systems and sources investigated, the two best systems were determined to be the high temperature methane/steam reforming reaction (HTCHP) coupled to a Very High Temperature Gas Cooled Reactor (VHTR) and the lower temperature, cyclohexane dehydrogenation reaction (LTCHP) coupled to existing sources such as coal or light water reactors. Solar and other developing technologies can best be coupled to the LTCHP. The preliminary economic and technical analyses show that both systems could transport heat at an incremental cost of approximately $1.50/GJ/160 km (in excess of the primary heat cost of $2.50/GJ), at system efficiencies above 80%. Solar heat can be transported at an incremental cost of $3/GJ/160 km. The use of the mixed feed evaporator concept developed in this work contributes significantly to reducing the transportation cost and increasing the efficiency of the system. The LTCHP shows the most promise of the two systems if the technical feasibility of the cyclic closed loop chemical reaction system can be established. An experimental program for establishing this feasibility is recommended. Since the VHTR is several years away from commercial demonstration and the HTCHP chemical technology is well developed, future HTCHP programs should be aimed at VHTR and interface problems.

  15. Northeastern Center for Chemical Energy Storage (NECCES)

    Energy Technology Data Exchange (ETDEWEB)

    Whittingham, M. Stanley [Stony Brook Univ., NY (United States)

    2015-07-31

    The chemical reactions that occur in batteries are complex, spanning a wide range of time and length scales from atomic jumps to the entire battery structure. The NECCES team of experimentalists and theorists made use of, and developed new methodologies to determine how model compound electrodes function in real time, as batteries are cycled. The team determined that kinetic control of intercalation reactions (reactions in which the crystalline structure is maintained) can be achieved by control of the materials morphology and explains and allows for the high rates of many intercalation reactions where the fundamental properties might indicate poor behavior in a battery application. The small overvoltage required for kinetic control is technically effective and economically feasible. A wide range of state-of-the-art operando techniques was developed to study materials under realistic battery conditions, which are now available to the scientific community. The team also investigated the key reaction steps in conversion electrodes, where the crystal structure is destroyed on reaction with lithium and rebuilt on lithium removal. These so-called conversion reactions have in principle much higher capacities, but were found to form very reactive discharge products that reduce the overall energy efficiency on cycling. It was found that by mixing either the anion, as in FeOF, or the cation, as in Cu1-yFeyF2, the capacity on cycling could be improved. The fundamental understanding of the reactions occurring in electrode materials gained in this study will allow for the development of much improved battery systems for energy storage. This will benefit the public in longer lived electronics, higher electric vehicle ranges at lower costs, and improved grid storage that also enables renewable energy supplies such as wind and solar.

  16. Significance of Xenobiotic Metabolism for Bioaccumulation Kinetics of Organic Chemicals in Gammarus pulex

    OpenAIRE

    Ashauer, Roman; Hintermeister, Anita; O’Connor, Isabel; Elumelu, Maline; Hollender, Juliane; Escher, Beate I

    2012-01-01

    Bioaccumulation and biotransformation are key toxicokinetic processes that modify toxicity of chemicals and sensitivity of organisms. Bioaccumulation kinetics vary greatly among organisms and chemicals; thus, we investigated the influence of biotransformation kinetics on bioaccumulation in a model aquatic invertebrate using fifteen 14C-labeled organic xenobiotics from diverse chemical classes and physicochemical properties (1,2,3-trichlorobenzene, imidacloprid, 4,6-dinitro-o-cresol, ethylacry...

  17. 76 FR 81441 - Proposed Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2011-12-28

    ... chemical substances rutile, tin zinc, calcium-doped (CAS No. 389623-01- 2) and rutile, tin zinc, sodium... orders. The two chemical substances are identified as rutile, tin zinc, calcium-doped (PMN P-06-36; CAS..., tin zinc, calcium-doped and (P- 06-37) Rutile, tin zinc, sodium-doped. CAS numbers: (P-06-36)...

  18. Significance of vapor phase chemical reactions on CVD rates predicted by chemically frozen and local thermochemical equilibrium boundary layer theories

    Science.gov (United States)

    Gokoglu, Suleyman A.

    1988-01-01

    This paper investigates the role played by vapor-phase chemical reactions on CVD rates by comparing the results of two extreme theories developed to predict CVD mass transport rates in the absence of interfacial kinetic barrier: one based on chemically frozen boundary layer and the other based on local thermochemical equilibrium. Both theories consider laminar convective-diffusion boundary layers at high Reynolds numbers and include thermal (Soret) diffusion and variable property effects. As an example, Na2SO4 deposition was studied. It was found that gas phase reactions have no important role on Na2SO4 deposition rates and on the predictions of the theories. The implications of the predictions of the two theories to other CVD systems are discussed.

  19. Chemically and Thermally Stable High Energy Density Silicone Composites Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Thermal energy storage systems with 300 ? 1000 kJ/kg energy density through either phase changes or chemical heat absorption are sought by NASA. This proposed...

  20. Producing Bio-Based Bulk Chemicals Using Industrial Biotechnology Saves Energy and Combats Climate Change

    OpenAIRE

    Hermann, B.G.; de Blok, K; Patel, M.K. (Martin)

    2007-01-01

    The production of bulk chemicals from biomass can make a significant contribution to solving two of the most urgent environmental problems: climate change and depletion of fossil energy. We analyzed current and future technology routes leading to 15 bulk chemicals using industrial biotechnology and calculated their CO2 emissions and fossil energy use. Savings of more than 100% in non-renewable energy use and greenhouse gas emissions are already possible with current state of the art biotechno...

  1. Chemical effects of ionizing radiation and sonic energy in the context of chemical evolution

    International Nuclear Information System (INIS)

    Ionizing radiation and sonic energy are considered as sources for chemical evolution processes. These sources have still a modest place in the interdisciplinary approach for the prebiological synthesis of organic compounds. Studies in Radiation Chemistry and Sonochemistry can provide a deeper insight into the chemical processes that may have importance for prebiotic chemistry. The present work concerns the analysis of some chemical reactions induced by ionizing radiation or cavitation in aqueous media that may be relevant to chemical evolution studies. (author)

  2. Bandwidth Study on Energy Use and Potential Energy Saving Opportunities in U.S. Chemical Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Sabine Brueske, Caroline Kramer, Aaron Fisher

    2015-06-01

    Energy bandwidth studies of U.S. manufacturing sectors can serve as foundational references in framing the range (or bandwidth) of potential energy savings opportunities. This bandwidth study examines energy consumption and potential energy savings opportunities in U.S. chemical manufacturing. The study relies on multiple sources to estimate the energy used in the production of 74 individual chemicals, representing 57% of sector-wide energy consumption. Energy savings opportunities for individual chemicals and for 15 subsectors of chemicals manufacturing are based on technologies currently in use or under development; these potential savings are then extrapolated to estimate sector-wide energy savings opportunity.

  3. 77 FR 66149 - Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2012-11-02

    ... Register issue of April 24, 1990 (55 FR 17376) (April 24, 1990 SNUR). Consult that preamble for further... a raw material for production of copper chemicals and as a raw material for the production of animal... (PCDFs) by high resolution gas chromatography/high resolution mass spectrometry (HRGC/HRMS) study...

  4. 77 FR 25235 - Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2012-04-27

    ...'s first direct final SNUR published in the Federal Register issue of April 24, 1990 (55 FR 17376... described in the New Chemicals Program's PBT category (64 FR 60194, November 4, 1999) (FRL-6097-7). EPA... alkenylsuccinate, ethanolamine salt (generic). CAS numbers: Not available. Basis for action: The consolidated...

  5. 77 FR 75390 - Significant New Use Rules on Certain Chemical Substances

    Science.gov (United States)

    2012-12-20

    ..., automotive coating, wastewater treatment, solid waste. CAS number: 1392095-50-9. Chemical substance definition: The waste solids produced from the treatment of wastewaters from automotive pretreatment... amount of the substances reasonably likely to be removed from the waste stream by such treatment may...

  6. 78 FR 50026 - Energy Efficiency and Conservation Loan Program Finding of No Significant Impact

    Science.gov (United States)

    2013-08-16

    ... Rural Utilities Service Energy Efficiency and Conservation Loan Program Finding of No Significant Impact... (RUS) has made a finding of no significant impact (FONSI) for implementing its new Energy Efficiency... 12 to authorize energy audits and energy efficiency measures and devices to reduce demand on...

  7. Producing Bio-Based Bulk Chemicals Using Industrial Biotechnology Saves Energy and Combats Climate Change

    NARCIS (Netherlands)

    Hermann, B.G.; Blok, K.; Patel, M.K.

    2007-01-01

    The production of bulk chemicals from biomass can make a significant contribution to solving two of the most urgent environmental problems: climate change and depletion of fossil energy. We analyzed current and future technology routes leading to 15 bulk chemicals using industrial biotechnology and

  8. The Trouble with Chemical Energy: Why Understanding Bond Energies Requires an Interdisciplinary Systems Approach

    OpenAIRE

    Cooper, Melanie M.; Klymkowsky, Michael W.

    2013-01-01

    Helping students understand “chemical energy” is notoriously difficult. Many hold inconsistent ideas about what energy is, how and why it changes during the course of a chemical reaction, and how these changes are related to bond energies and reaction dynamics. There are (at least) three major sources for this problem: 1) the way biologists talk about chemical energy (which is also the way we talk about energy in everyday life); 2) the macroscopic approach to energy concepts that is common in...

  9. Chemical defences in leaf beetles and their larvae: The ecological, evolutionary and taxonomic significance

    OpenAIRE

    Pasteels, Jacques M.; Rowell-Rahier, Martine; Braekman Jean-Claude; Daloze, Désiré

    2009-01-01

    The chemical defences of the Chrysomelinae are reviewed. Defensive glandular secretions have evolved independently in larvae and adults, and faster than the morphology of the glands. Both characters are used in a phylogenetic study of the Chrysomelini, disclosing suprageneric affinities. First, a close relationship between the Chrysomelina and Phratora is proposed. Secondly, Leptinotarsa and Gonioctena are probably more closely related to the Chrysolinina than to the Chrysomelina and Phratora...

  10. Significance of the chemical and volume control system in corrosion product transport to PWR coolants

    International Nuclear Information System (INIS)

    A series of chemistry monitoring tests were carried out at the Doel 2 PWR to evaluate the performance of the chemical volume control system (CVCS) and its possible contribution to elemental cobalt input into the coolant circuit. A sampling probe was installed in the recharging line to assess the overall effect of the CVCS. These studies showed that the CVCS was not a potent source of cobalt in the reactor's 13th cycle. A number of observations were made on the efficiency of the purification plant and the effects on soluble and insoluble elemental and radioactive species in the recharged water relative to the primary circuit. (author)

  11. FMC Chemicals: Burner Management System Upgrade Improves Performance and Saves Energy at a Chemical Plant

    Energy Technology Data Exchange (ETDEWEB)

    None

    2004-07-01

    FMC Chemicals Corporation increased the efficiency of two large coal-fired boilers at its soda ash mine in Green River, Wyoming, by upgrading the burner management system. The project yields annual energy savings of 250,000 MMBtu.

  12. Allothermal gasification of biomass into chemicals and secondary energy carriers

    Energy Technology Data Exchange (ETDEWEB)

    Zwart, R.W.R. [ECN Biomass, Coal and Environmental Research, Petten (Netherlands)

    2009-09-15

    The outline of this presentation on the title subject states: Motivation for polygeneration; Allothermal gasification: the MILENA at ECN; Primary gas cleaning: the OLGA for tar removal; Possible secondary energy carriers; Possible chemicals; Polygeneration concept and its feasibility.

  13. A new principle of synthetic cascade utilization of chemical energy and physical energy

    Institute of Scientific and Technical Information of China (English)

    JIN Hongguang; HONG Hui; WANG Baoqun; HAN Wei; LIN Rumou

    2005-01-01

    We propose a new principle of the cascade utilization of both chemical energy and physical energy in energy systems with the integration of chemical processes and thermal cycles. Particularly, a general equation of energy levels of substance, Gibbs free energy of chemical reaction and physical energy is explicitly founded. On the basis of this equation, a chemical-looping combustion and an indirect combustion are investigated. Furthermore, a mechanism of energy release, with the combination of decreasing the energy level of Gibbs free energy and upgrading the energy level of low or middle- temperature thermal energy, is clarified. The promising results obtained here establish a theoretical basis for the further investigation of multi-function systems in which energy and the environment are compatible, and create a new approach to improve the performance of traditional thermal cycles.

  14. Significance of oil droplets in chemically enhanced water-accommodated fraction

    Energy Technology Data Exchange (ETDEWEB)

    Ramachandran, S. [Queen' s Univ., Kingston, ON (Canada). School of Environmental Studies; Hodson, P.V.; Lee, K. [Department of Fisheries and Oceans, Dartmouth, NS (Canada). Bedford Inst. of Oceanography

    2003-07-01

    This presentation described the controversial use of chemical dispersions to treat oil spills on water. Dispersants break up the spill in order to reduce shoreline impacts, but the dispersant drives the oil into the water column in the form of droplets, thereby temporarily increasing hydrocarbon concentrations and causing negative impacts on aquatic organisms. Exposure experiments have been conducted on rainbow trout exposed to Mesa and Scotian Light Crude Oil, with and without oil droplets. The studies showed that the levels of polycyclic aromatic hydrocarbons (PAH) was higher in the trout exposed to Corexit water-accommodated fractions, compared to water-accommodated fractions. The results suggest that dispersing crude oil sustains hydrocarbon concentrations in a larger volume of water than if it were not dispersed. The oil droplets increase the partitioning of PAH into the water solution. They adhere to the gills of the fish, thereby facilitating direct uptake.

  15. Periodic Table Target: A Game that Introduces the Biological Significance of Chemical Element Periodicity

    Science.gov (United States)

    Sevcik, Richard S.; McGinty, Ragan L.; Schultz, Linda D.; Alexander, Susan V.

    2008-01-01

    Periodic Table Target, a game for middle school or high school students, familiarizes students with the form of the periodic table and the biological significance of different elements. The Periodic Table Target game board is constructed as a class project, and the game is played to reinforce the content. Students are assigned several elements…

  16. Significant observations from a PWR steam generator chemical cleaning qualification test program

    International Nuclear Information System (INIS)

    A qualification test program for the chemical cleaning of the secondary side of steam generators was conducted in anticipation of a potential application at Indian Point 2 (IP-2). The sludge removal effectiveness was evaluated using a large-scale test facility and both simulated consolidated sludge samples and sludge removed from IP-2 steam generators during prior sludge lancing. The test also mocked up the weld geometries and locations for an accurate galvanic corrosion assessment. This large-scale test and other preliminary tests had the following three aims: (1) optimize and demonstrate the sludge removal effectiveness of the Electric Power Research Institute/Steam Generator Owners Group (EPRI/SGOG) generic cleaning process for the Westinghouse Model 44 steam generators, (2) determine the corrosion effects of the process on Westinghouse Model 44 steam generator materials that would be exposed to the process, and (3) identify technical issues that should be addressed prior to field implementation of the process. The qualification test program also included the evaluation of an eddy current technique that measures sludge height in the presence of copper (IP-2 sludge contains more than 30 percent copper)

  17. Germ cell toxicity: significance in genetic and fertility effects of radiation and chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Oakberg, E.F.

    1983-01-01

    The response of the male and female to radiation and chemicals is different. Any loss of oocytes in the female cannot be replaced, and if severe enough, will result in a shortening of the reproductive span. In the male, a temporary sterile period may be induced owing to destruction of the differentiating spermatogonia, but the stem cells are the most resistant spermatogonial type, are capable of repopulating the seminiferous epithelium, and fertility usually returns. The response of both the male and female changes with development of the embryonic to the adult gonad, and with differentiation and maturation in the adult. The primordial germ cells, early oocytes, and differentiating spermatogonia of the adult male are unusually sensitive to the cytotoxic action of noxious agents, but each agent elicits a specific response owing to the intricate biochemical and physiological changes associated with development and maturation of the gametes. The relationship of germ cell killing to fertility is direct, and long-term fertility effects can be predicted from histological analysis of the gonads. The relationship to genetic effects, on the other hand, is indirect, and acts primarily by limiting the cell stages available for testing, by affecting the distribution of mitotically active stem cells among the different stages of the mitotic cycle, and thereby, changing both the type and frequency of genetic effects observed. 100 references, 38 figures, 7 tables.

  18. Germ cell toxicity: significance in genetic and fertility effects of radiation and chemicals

    International Nuclear Information System (INIS)

    The response of the male and female to radiation and chemicals is different. Any loss of oocytes in the female cannot be replaced, and if severe enough, will result in a shortening of the reproductive span. In the male, a temporary sterile period may be induced owing to destruction of the differentiating spermatogonia, but the stem cells are the most resistant spermatogonial type, are capable of repopulating the seminiferous epithelium, and fertility usually returns. The response of both the male and female changes with development of the embryonic to the adult gonad, and with differentiation and maturation in the adult. The primordial germ cells, early oocytes, and differentiating spermatogonia of the adult male are unusually sensitive to the cytotoxic action of noxious agents, but each agent elicits a specific response owing to the intricate biochemical and physiological changes associated with development and maturation of the gametes. The relationship of germ cell killing to fertility is direct, and long-term fertility effects can be predicted from histological analysis of the gonads. The relationship to genetic effects, on the other hand, is indirect, and acts primarily by limiting the cell stages available for testing, by affecting the distribution of mitotically active stem cells among the different stages of the mitotic cycle, and thereby, changing both the type and frequency of genetic effects observed. 100 references, 38 figures, 7 tables

  19. Chemical Expansion: Implications for Electrochemical Energy Storage and Conversion Devices

    DEFF Research Database (Denmark)

    Bishop, S.R.; Marrocchelli, D.; Chatzichristodoulou, Christodoulos;

    2014-01-01

    modeling and an overview of factors impacting chemical expansion. We discuss the implications of chemical expansion for mechanical stability and functionality in the energy applications above, as well as in other oxide-based systems. The use of chemical expansion as a new means to probe other materials......Many energy-related materials rely on the uptake and release of large quantities of ions, for example, Li+ in batteries, H+ in hydrogen storage materials, and O2− in solid-oxide fuel cell and related materials. These compositional changes often result in large volumetric dilation of the material......, commonly referred to as chemical expansion. This article reviews the current knowledge of chemical expansion and aspires to facilitate and promote future research in this field by providing a taxonomy for its sources, along with recent atomistic insights of its origin, aided by recent computational...

  20. Germ cell toxicity: significance in genetic and fertility effects of radiation and chemicals

    International Nuclear Information System (INIS)

    The primordial germ cells originate in the region of the caudal end of the primitive streak, root of the allantois, and yolk sac splanchnopleure, and migrate to the gonadal ridges where they divide to form the oogonia of the female and gonocytes of the male. In the female, the transition to oocytes occurs in utero, and the female mammal is born with a finite number of oocytes that cannot be replaced. By contrast, the gonocytes of the male initiate divisions soon after birth to form the spermatogonial stem cells, which persist throughout reproductive life of the male and are capable of regenerating the seminiferous epithelium after injury. As a result of these basic differences in gametogenesis, the response of the male and female to radiation and chemicals is different. The response of both the male and female changes with development of the embryonic to the adult gonad, and with differentiation and maturation in the adult. The primordial germ cells, early oocytes, and differentiating spermatogonia of the adult male are unusually sensitive to the cytotoxic action of noxious agents, but each agent elicits a specific response owing to the intricate biochemical and physiological changes associated with development and maturation of the gametes. The relationship of germ cell killing to fertility is direct, and long-term fertility effects can be predicted from histological analysis of the gonads. The relationship to genetic effects, on the other hand, is indirect, and acts primarily by limiting the cell stages available for testing, by affecting the distribution of mitotically active stem cells among the different stages of the mitotic cycle, and thereby changing both the type and frequency of genetic effects observed

  1. A new approach of cascade utilization of the chemical energy of fuel

    Institute of Scientific and Technical Information of China (English)

    HAN Wei; JIN Hongguang; LIN Rumou

    2006-01-01

    The indirect release of chemical energy of fuel is investigated, and a new mechanism is proposed to identify the cascade utilization of chemical energy of fuel more clearly. Based on the concept of energy level, the internal phenomenon of the indirect chemical energy release is disclosed, and the equations of energy level describing the utilization of chemical energy and thermal energy during the indirect chemical energy release process are obtained. From theoretical analysis, we find that the superiority of the indirect chemical energy release of fuel comes from the cascade utilization of the fuel's chemical energy. Moreover, the cascade utilization of chemical energy is verified by the investigation of CRGT (chemically recuperated gas turbine). As a result, the thermal exergy obtained from the chemical energy release of fuel increases by 2 % -3 %. The results obtained here may help a deeper understanding of indirect chemical energy release of fuel and provide a theoretical basis for the synthesis of innovative energy systems.

  2. Concept for production of chemicals and power using geothermal energy

    International Nuclear Information System (INIS)

    This paper presents a concept for conducting commercial chemical reactions and production of power using geothermal heat. The high pressures (Ps) and temperatures (Ts) that fluids attain in deep reservoirs can be used to manufacture chemicals or decontaminate wastes. High P reactions which can be expensive and/or unsafe to conduct above ground can be conducted in geothermal reservoirs using closed designs. We present examples of reactions that could benefit from Enhanced Geothermal Systems (EGS) including production of ammonia (NH3), supercritical oxidation of wastewater contaminants, production of hydrogen (H2) by steam reforming of methanol (CH3OH) and partial oxidation of methane (CH4) to produce CH3OH. -- Highlights: • Co-production of power and chemicals using geothermal energy is discussed. • Process captures energy more efficiently as chemical, sensible and latent heat. • The co-production process can improve the economics of geothermal energy. • Novel designs are required for insure safety and guard against contamination

  3. Chemical energy sources transformations by remote experiment

    OpenAIRE

    Tkáč, Lukáš; Schauer, František; Gerhátová, Žaneta

    2014-01-01

    The paper describes the first experience with the set up, functioning and data evaluation of the remote experiment "Energy transformation" accessible via Internet (http://remotelab10.truni.sk ) as a part of the e-laboratory at the Department of Physics, Faculty of Education, Trnava University in Trnava, Slovakia. The remote experiment control and data acquisition is based on the system ISES (Internet School Experimental System) and its control program and www page are built using the environm...

  4. Contents of chemical elements in stomach during prenatal development: different age-dependent dynamical changes and their significance

    Institute of Scientific and Technical Information of China (English)

    Shao-Fan Hou; Hai-Rong Li; Li-Zhen Wang; De-Zhu Li; Lin-Sheng Yang; Chong-Zheng Li

    2003-01-01

    AIM: To observe dynamic of different chemical elements in stomach tissue during fetal development.METHODS: To determine contents of the 21 chemical elements in each stomach samples from fetus aging four to ten months. The content values were compared to those from adult tissue samples, and the values for each month group were also analyzed for dynamic changes.RESULTS: Three representations were found regarding the relationship between contents of the elements and ages of the fetus, including the positive correlative (K), reversely correlative (Na, Ca, P, Al, Cu, Zn, Fe, Mn, Cr, Sr, Li, Cd, Ba,Se ) and irrelevant groups (Mg, Co, Ni, V, Pb, Ti).CONCLUSION: The chemical elements' contents in stomach tissues were found to change dynamically with the stomach weights. The age-dependent representations for different chemical elements during the prenatal development may be of some significance for assessing development of fetal stomach and some chemical elements. The data may be helpful for the nutritional balance of fetus and mothers during prenatal development and even the perinatal stages.

  5. Chemical dynamics in time and energy space

    Energy Technology Data Exchange (ETDEWEB)

    Myers, J.D.

    1993-04-01

    The development of a versatile picosecond ultraviolet/vacuum ultraviolet temporal spectrometer and its potential use for measuring internal energy redistribution in isolated molecules are described in detail. A detailed description of the double-pass Nd:YAG amplifier and the dye amplifiers is given with the pulse energies achieved in the visible, ultraviolet, and vacuum ultraviolet. The amplified visible pulses are shown to be of sub-picosecond duration and near transform limited. The instrument`s temporal response ({le}10 ps) is derived from an instrument limited measurement of the dissociation lifetime of methyl iodide at 266 nm. The methyl iodide experiment is used to discuss the various sources of noise and background signals that are intrinsic to this type of experiment. Non-time-resolved experiments measuring the branching ratio and kinetic energy distributions of products from the 193 nm photodissociation of cyclopentadiene and thiophene are presented. These studies were done using the molecular beam Photofragment Translational Spectroscopy (PTS) technique. The results from the cyclopentadiene experiment confirm that H atom elimination to yield the cyclopentadienyl radical is the dominant dissociation channel. A barrier of {ge}5 kcal/mol can be understood in terms of the delocalization of the radical electron of the cyclopentadienyl fragment. A concerted elimination yielding cyclopropene and acetylene was also observed and is proposed to occur via a bicyclo-[2.1.0]pent-2-ene intermediate. Two other channels, yielding acetylene plus the CH{sub 2}CHCH triplet carbene, and CH{sub 2} plus 1-buten-3-yne, are postulated to occur via ring opening. The implications of the experimental results for bulk thermal oxidation and pyrolysis models are discussed. The thiophene experiment shows six competing dissociation channels. The postulated intermediates for the various thiophene dissociation channels include bicyclo, ring opened, and possibly ring contracted forms.

  6. The patterns of energy use in the chemical industry

    International Nuclear Information System (INIS)

    This paper was sculpted from a report commissioned by the Department of Energy to assess the impact of proposed energy taxes on energy use by the US chemical industry. The discussion of energy taxes is eliminated here, however the broader discussion of the impact of energy prices on energy use is retained. The US chemical industry is currently the world leader by many important measures, such as technology contributions and employment. This leadership traces to a slate of advantages: science base, low cost energy, large market and economic/political stability. The focus of this paper is on the patterns of energy use: (1) There is an optimum economic trade of capital against energy. Industry optimizes this trade to lower its costs. For the large volume chemicals which dominate energy use, this tradable capital cost exceeds energy cost by a factor of 1.5. (2) The capital/energy trade follows clearly defined rules. The basic rules are rooted in thermodynamics. (3) An increase in energy prices would result in a drop in process energy use: a doubling of process energy prices would cut process energy use by approximately 1/3 but the capital cost would be in excess of $100 billion if driven into a short time span, such as 5 years. This is because of the long useful lifetime of capital facilities. (4) Process energy is about half the total energy use, with feedstock being the balance. Feedstock use is much less sensitive to price. Restated, the doubling of energy price will result in roughly a 1/6 reduction in total energy use. (5) Technology progress will also reduce energy use. This reduction is distinct from the impact of energy price. Technological progress will be at least as important in reducing energy use as will energy pricing, for the foreseeable future. (6) Technology progress can be sorted into two themes: (a) Learning curve improvements, which are almost inherent in the production process and the nature of competition; and (b) Breakthroughs that happen in a

  7. Chemical reactions driven by concentrated solar energy

    Science.gov (United States)

    Levy, Moshe

    Solar energy can be used for driving endothermic reactions, either photochemically or thermally. The fraction of the solar spectrum that can be photochemically active is quite small. Therefore, it is desirable to be able to combine photochemical and thermal processes in order to increase the overall efficiency. Two thermally driven reactions are being studied: oil shale gasification and methane reforming. In both cases, the major part of the work was done in opaque metal reactors where photochemical reactions cannot take place. We then proceeded working in transparent quartz reactors. The results are preliminary, but they seem to indicate that there may be some photochemical enhancement. The experimental solar facilities used for this work include the 30 kW Schaeffer Solar Furnace and the 3 MW Solar Central Receiver in operation at the Weizmann Institute. The furnace consists of a 96 sq. m flat heliostat, that follows the sun by computer control. It reflects the solar radiation onto a spherical concentrator, 7.3 m in diameter, with a rim angle of 65 degrees. The furnace was characterized by radiometric and calorimetric measurements to show a solar concentration ratio of over 10,000 suns. The central receiver consists of 64 concave heliostats, 54 sq. m each, arranged in a north field and facing a 52 m high tower. The tower has five target levels that can be used simultaneously. The experiments with the shale gasification were carried out at the lowest level, 20 m above ground, which has the lowest solar efficiency and is assigned for low power experiments. We used secondary concentrators to boost the solar flux.

  8. Significant decimal digits for energy representation on short-word computers

    International Nuclear Information System (INIS)

    The general belief that single precision floating point numbers have always at least seven significant decimal digits on short word computers such as IBM is erroneous. Seven significant digits are required however for representing the energy variable in nuclear cross-section data sets containing sharp p-wave resonances at 0 Kelvin. It is suggested that either the energy variable is stored in double precision or that cross-section resonances are reconstructed to room temperature or higher on short word computers

  9. Chemical process safety management within the Department of Energy

    International Nuclear Information System (INIS)

    Although the Department of Energy (DOE) is not well known for its chemical processing activities, the DOE does have a variety of chemical processes covered under OSHA's Rule for Process Safety Management of Highly Hazardous Chemicals (the PSM Standard). DOE, like industry, is obligated to comply with the PSM Standard. The shift in the mission of DOE away from defense programs toward environmental restoration and waste management has affected these newly forming process safety management programs within DOE. This paper describes the progress made in implementing effective process safety management programs required by the PSM Standard and discusses some of the trends that have supported efforts to reduce chemical process risks within the DOE. In June of 1994, a survey of chemicals exceeding OSHA PSM or EPA Risk Management Program threshold quantities (TQs) at DOE sites found that there were 22 processes that utilized toxic or reactive chemicals over TQs; there were 13 processes involving flammable gases and liquids over TQs; and explosives manufacturing occurred at 4 sites. Examination of the survey results showed that 12 of the 22 processes involving toxic chemicals involved the use of chlorine for water treatment systems. The processes involving flammable gases and liquids were located at the Strategic Petroleum Reserve and Naval petroleum Reserve sites

  10. A Significance-Driven Programming Framework for Energy-Constrained Approximate Computing

    OpenAIRE

    Vassiliadis, Vassilis; Chalios, Charalambos; Parasyris, Konstantinos; Antonopoulos, Christos D.; Lalis, Spyros; Bellas, Nikolaos; Vandierendonck, Hans; Nikolopoulos, Dimitrios

    2015-01-01

    Approximate execution is a viable technique for energy-con\\-strained environments, provided that applications have the mechanisms to produce outputs of the highest possible quality within the given energy budget. We introduce a framework for energy-constrained execution with controlled and graceful quality loss. A simple programming model allows users to express the relative importance of computations for the quality of the end result, as well as minimum quality requirements. The significance...

  11. Energy use and energy intensity of the U.S. chemical industry

    OpenAIRE

    Worrell, Ernst; Phylipsen, Dian; Einstein, Dan; Martin, Nathan

    2000-01-01

    The U.S. chemical industry is the largest in the world, and responsible for about 11 percent of the U.S. industrial production measured as value added. It consumes approximately 20 percent of total industrial energy consumption in the U.S. (1994), and contributes in similar proportions to U.S. greenhouse gas emissions. Surprisingly, there is not much information on energy use and energy intensity in the chemical industry available in the public domain. This report provides detailed info...

  12. Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: July-December 1998

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1999-06-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period July-December 1998. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications.

  13. Quarterly Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: April-June 1998

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1999-04-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during th eperiod April-June 1998. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications.

  14. Chemical energy conversion as enabling factor to move to a renewable energy economy

    Energy Technology Data Exchange (ETDEWEB)

    Abate, Salvatore; Centi, Gabriele; Perathoner, Siglinda [Mesina Univ. (Italy). Section Industrial Chemistry; ERIC aisbl and INSTM/CASPE, Messina (Italy)

    2015-07-01

    The role of chemical energy storage and solar fuels as key elements for the sustainable chemical and energy production is discussed in this concept paper. It is shown how chemical energy storage, with the development of drop-in carbon-based solar fuels, will play a central role in the future low-carbon economy, but it is necessary to consider its out-of-the-grid use, rather than being limited to be a tool for smart grids. Related aspects discussed are the possibility to: (i) enable a system of trading renewable energy on a world scale (out-of-the-grid), including the possibility to exploit actually unused remote resources, (ii) develop a solar-driven and low-carbon chemical production, which reduces the use of fossil fuels and (iii) create a distributed energy production, going beyond the actual limitations and dependence on the grid.

  15. Chemical energy conversion as enabling factor to move to a renewable energy economy

    International Nuclear Information System (INIS)

    The role of chemical energy storage and solar fuels as key elements for the sustainable chemical and energy production is discussed in this concept paper. It is shown how chemical energy storage, with the development of drop-in carbon-based solar fuels, will play a central role in the future low-carbon economy, but it is necessary to consider its out-of-the-grid use, rather than being limited to be a tool for smart grids. Related aspects discussed are the possibility to: (i) enable a system of trading renewable energy on a world scale (out-of-the-grid), including the possibility to exploit actually unused remote resources, (ii) develop a solar-driven and low-carbon chemical production, which reduces the use of fossil fuels and (iii) create a distributed energy production, going beyond the actual limitations and dependence on the grid.

  16. Solar-driven chemical energy source for a Martian biota

    Science.gov (United States)

    Clark, B. C.

    1979-01-01

    Microorganisms deep in the Martian soil could derive energy indirectly from the sun via chemical reactions involving atmospheric photolysis products of the solar ultraviolet flux. The Viking discovery of a chemically uniform regolith which, though poor in organics, is rich in sulfur-containing compounds suggests reaction sequences in which sulfur is recycled through reduced and oxidized states by biologically catalyzed reactions with photochemically-produced atmospheric constituents. One candidate reaction, reduction of soil sulfate minerals by molecular hydrogen, is already exploited on earth by bacteria of the ubiquitous and tenacious Desulfovibrio genus.

  17. Potential of best practice technology to improve energy efficiency in the global chemical and petrochemical sector

    International Nuclear Information System (INIS)

    The chemical and petrochemical sector is by far the largest industrial energy user, accounting for 30% of the industry's total final energy use. However, due to its complexity its energy efficiency potential is not well understood. This article analyses the energy efficiency potential on a country level if Best Practice Technologies (BPT) were implemented in chemical processes. Two approaches are applied and an improved dataset referring to Europe has been developed for BPT energy use. This methodology has been applied to 66 products in fifteen countries that represent 70% of chemical and petrochemical sector's energy use worldwide. The results suggest a global energy efficiency potential of 16% for this sector, excluding savings in electricity use and by higher levels of process integration, combined heat and power (CHP) and post-consumer plastic waste treatment. The results are more accurate than previous estimates. The results suggest significant differences between countries, but a cross-check based on two different methods shows that important methodological and data issues remain to be resolved. Further refinement is needed for target setting, monitoring and informing energy and climate negotiation processes. For the short and medium term, a combination of benchmarking and country level analysis is recommended. -- Highlights: → Best Practice Technologies (BPTs) offer energy savings in the chemical industry. → Two approaches are applied based on an improved BPT dataset covering 66 chemicals. → Worldwide, BPTs offer 16% energy saving potentials excluding electricity use. → Process integration, combined heat and power and recycling offer further potential. → Results need to be improved by resolving important methodological and data issues.

  18. Thermal energy storage using thermo-chemical heat pump

    International Nuclear Information System (INIS)

    Highlights: ► Understanding of the performance of thermo chemical heat pump. ► Tool for storing thermal energy. ► Parameters that affect the amount of thermal stored energy. ► Lithium chloride has better effect on storing thermal energy. - Abstract: A theoretical study was performed to investigate the potential of storing thermal energy using a heat pump which is a thermo-chemical storage system consisting of water as sorbet, and sodium chloride as the sorbent. The effect of different parameters namely; the amount of vaporized water from the evaporator, the system initial temperature and the type of salt on the increase in temperature of the salt was investigated and hence on the performance of the thermo chemical heat pump. It was found that the performance of the heat pump improves with the initial system temperature, with the amount of water vaporized and with the water remaining in the system. Finally it was also found that lithium chloride salt has higher effect on the performance of the heat pump that of sodium chloride.

  19. Free Energy Transduction in a Chemical Motor Model

    CERN Document Server

    Baker, J E

    2003-01-01

    Motor enzymes catalyze chemical reactions, like the hydrolysis of ATP, and in the process they also perform work. Recent studies indicate that motor enzymes perform work with specific intermediate steps in their catalyzed reactions, challenging the classic view (in Brownian motor models) that work can only be performed within biochemical states. An alternative class of models (chemical motor models) has emerged in which motors perform work with biochemical transitions, but many of these models lack a solid physicochemical foundation. In this paper, I develop a self consistent framework for chemical motor models. This novel framework accommodates multiple pathways for free energy transfer, predicts rich behaviors from the simplest multi motor systems, and provides important new insights into muscle and motor function.

  20. Fate and residues of pesticides and other agriculturally significant chemicals in livestock and poultry as determined by radiotracer techniques

    International Nuclear Information System (INIS)

    Studies in the author's laboratories during this 5-year program have involved the use of radioisotope techniques (radiocarbon, tritium) to evaluate the fate of several agriculturally-significant chemicals in food animals. Included were studies of the fate of radiolabeled preparations of the organophosphorus insecticide, RH-0994, in a lactating cow; of the organophosphorus insecticide, coumaphos, after dermal application to goats as a pour on formulation; of the synthetic pyrethroid insecticide, resmethrin, in lactating cattle and laying hens; of the growth promoting drug, β-estradiol, after intramuscular injection into steer calves; of the environmental contaminants 4-chlorophenyl methyl sulfide and -sulfone in cattle and sheep; of the potent photosensitizer, xanthotoxin, in a goat, in bovine rumen fluid, and in laying hens; and of the trichothecene mycotoxin, T-2 toxin, in bovine rumen fluid. In these studies, particular emphasis was placed upon elucidation of the chemical nature of metabolic products generated, and upon quantification as appropriate of residues retained by edible tissues or secreted into milk or eggs. (author)

  1. Significance of stable and unstable cytogenetic biomarkers in estimation of genome damage in subjects exposed to physical and chemical agents

    International Nuclear Information System (INIS)

    The last few years have shown that cytogenetic biomarkers do predict increased cancer risk. The most frequently used biomarkers in genetic toxicology are chromosome aberration assay (CA) and micronucleus (MN) assay. Fluorescent in situ hybridisation (FISH), in turn, enables analysis of translocation as a stable genome damage. With technological development, working environment has become associated with complex exposure to ionising and non-ionising radiation and chemical agents. A follow-up of 1200 subjects occupationally exposed to ionising radiation and chemical agents using CA and MN showed that the highest deviations from control values were detected in complex exposure to ionising radiation and ultrasound or to radioisotopes in medicine and in industrial radiography and to ionising radiation in specific jobs in nuclear plants. FISH used in a group of subjects exposed to gamma radiation and ultrasound showed that translocation frequency could rise even when CA frequency is within control values. This example shows that health risk is present even when results obtained by routine methods for the last few decades do not deviate from control values and that a decrease in permissible doses does not protect from accumulated genome damage during employment under different conditions. As biological effects of complex exposure are not possible to monitor by physical measurements, cytogenetic biomarkers are the only reliable tools to evaluate of genome damage and significant parameters in regulating health surveillance of exposed subjects.(author)

  2. Proceedings of the DOE chemical energy storage and hydrogen energy systems contracts review

    Energy Technology Data Exchange (ETDEWEB)

    1980-02-01

    Sessions were held on electrolysis-based hydrogen storage systems, hydrogen production, hydrogen storage systems, hydrogen storage materials, end-use applications and system studies, chemical heat pump/chemical energy storage systems, systems studies and assessment, thermochemical hydrogen production cycles, advanced production concepts, and containment materials. (LHK)

  3. Thermal, Spectroscopic and Chemical Characterization of Biofield Energy Treated Anisole

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    The objective of the present study was to evaluate the impact of biofield energy treatment on the thermal, spectroscopic, and chemical properties of anisole by various analytical methods such as gas chromatography-mass spectrometry (GC-MS), high performance liquid chromatography (HPLC), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR) spectroscopy, and ultraviolet-visible (UV-Vis) spectroscopy. The anisole sample was divided into two parts, control and treated. The ...

  4. Prevention of significant deterioration: implications for energy research and development. [Air quality

    Energy Technology Data Exchange (ETDEWEB)

    Garvey, D. B.; Streets, D. G.; Kung, S. L.; Leppert, G.

    1978-02-10

    The Clean Air Act Amendments of 1977 contain provisions designed to prevent the significcant deterioration of air quality in areas of the nation where the ambient air is cleaner than the minimum levels required to meet National Ambient Air Quality Standards (NAAQS). The legislation will affect the economic competitiveness of alternative fuel cycles for the generation of power and will have implications for the future siting of all new major sources of emissions. This paper examines the potential effects of Prevention of Significant Deterioration (PSD) legislation on energy technologies and industrial facilities and, in particular, the possible effects on energy research and development programs of the Department of Energy (DOE).

  5. Testing chemical composition of highest energy comic rays

    Czech Academy of Sciences Publication Activity Database

    Nosek, D.; Vícha, Jakub; Nosková, J.; Ebr, Jan

    Singapore : International Union of Pure and Applied Physics (IUPAP), 2013, s. 0472. ISBN 978-85-89064-29-3. [The 33rd International Cosmic Ray Conference (ICRC2013). Rio de Janeiro (BR), 02.07.2013-09.07.2013] R&D Projects: GA MŠk(CZ) LG13007 Institutional support: RVO:68378271 Keywords : ultra-high energy cosmic rays * chemical composition Subject RIV: BF - Elementary Particles and High Energy Physics http://www.cbpf.br/~icrc2013/proc_icrc2013.html

  6. Arrival directions and chemical composition of ultrahigh energy cosmic rays

    International Nuclear Information System (INIS)

    To estimate the chemical composition of ultrahigh energy cosmic rays we apply an approach using the well established magnitude and character of the galactic magnetic field and also both theoretical and experimental distributions of showers in galactic latitude. Arrival directions of cosmic rays in the energy region of (0.8-4)x1019 eV in galactic latitude are consistent with theoretical calculations, if cosmic rays are mainly heavy nuclei. An excess flux of cosmic rays at ∼ 1019 eV from the galactic plane is found

  7. Chemical metrology, strategic job for the Chilean Nuclear Energy Commission

    International Nuclear Information System (INIS)

    The National Standardization Institute's (INN) Metrology unit prepared a study in 1996 to evaluate the impact of metrological activity in Chile. This study was based on a survey of the supply and demand of metrological services and on studies of the behavior of the production system and technological services in Chile during the period 1990-1996. With the information obtained in this study the economic impact resulting from the lack of a national metrology system could be evaluated. This impact was estimated to be a 5% loss in gross national product equal to 125-500 million dollars because of direct product rejection in the mining, fisheries, agricultural and manufacturing sectors. Chemical measurements are responsible for 50% of these losses. In response to this need and coordinated by the INN, a metrological network of reference laboratories began to operate in 1997 for the principal physical magnitudes (mass, temperature, longitude and force) and a CORFO-FDI project began in 2001 that includes the chemical magnitudes. The Chilean Nuclear Energy Commission, aware of the problem's importance and the amount of economic damage that the country may suffer, as a result of these deficiencies, has formed a Chemical Metrology Unit to provide technical support. It aims to raise the standards of local analytical laboratories by providing international recognition to the export sector. Nuclear analytical techniques are used as reference methods. This work describes the laboratories that are included in this Chemical Metrology Unit and the historical contribution to the development of local analytical chemistry. The national and international projects are described together with the publications they have generated. The quality assurance program applied to the laboratories is described as well, which has led to the accreditation of the analytical chemical assays. The procedures used for validation and calculation of uncertain nuclear methodologies are described together with

  8. Green energy as an alternative to inorganic chemical energy (ICE) for sustainable development in developing countries

    Energy Technology Data Exchange (ETDEWEB)

    Shrestra, G.L. [Green Energy Mission, (Nepal)

    1995-12-31

    In the developing and least developed countries severe deforestation by the ever increasing population needing fuelwood, timber and non-timber substitutes, more forests in circumstances where climatic conditions are highly variable, combined with intensive use of unbalanced doses of inorganic agricultural chemicals have caused uncontrolled agricultural land degradation, top soil erosion, land slides, flooding and deposits of debris as well as bank erosion in rivers. This paper summarises important factors relating to the developing and least developed countries, and emphasises the commercial application of green energy plants as well as bio-technologically developed green energy at the farm and village levels. There are alternatives to inorganic chemical energy applications for sustainable development in the developing and least developed countries. The examples cited in the paper from Nepal are to inform the scientific community of the real situation of green energy as an alternative to inorganic chemical energy for sustainable development. (author). 5 tabs.

  9. Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: January--March 1997

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1998-01-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division (CTD) at Oak Ridge National Laboratory (ORNL) during the period January--March 1997. Created in March 1997 when the CTD Chemical Development and Energy Research sections were combined, the Chemical and Energy Research Section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within seven major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Separations and Materials Synthesis, Solution Thermodynamics, and Biotechnology Research. The name of a technical contact is included with each task described in the report, and readers are encouraged to contact these individuals if they need additional information.

  10. Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels

    Energy Technology Data Exchange (ETDEWEB)

    Kucharski, TJ; Ferralis, N; Kolpak, AM; Zheng, JO; Nocera, DG; Grossman, JC

    2014-04-13

    Large-scale utilization of solar-energy resources will require considerable advances in energy-storage technologies to meet ever-increasing global energy demands. Other than liquid fuels, existing energy-storage materials do not provide the requisite combination of high energy density, high stability, easy handling, transportability and low cost. New hybrid solar thermal fuels, composed of photoswitchable molecules on rigid, low-mass nanostructures, transcend the physical limitations of molecular solar thermal fuels by introducing local sterically constrained environments in which interactions between chromophores can be tuned. We demonstrate this principle of a hybrid solar thermal fuel using azobenzene-functionalized carbon nanotubes. We show that, on composite bundling, the amount of energy stored per azobenzene more than doubles from 58 to 120 kJ mol(-1), and the material also maintains robust cyclability and stability. Our results demonstrate that solar thermal fuels composed of molecule-nanostructure hybrids can exhibit significantly enhanced energy-storage capabilities through the generation of template-enforced steric strain.

  11. Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels

    Science.gov (United States)

    Kucharski, Timothy J.; Ferralis, Nicola; Kolpak, Alexie M.; Zheng, Jennie O.; Nocera, Daniel G.; Grossman, Jeffrey C.

    2014-05-01

    Large-scale utilization of solar-energy resources will require considerable advances in energy-storage technologies to meet ever-increasing global energy demands. Other than liquid fuels, existing energy-storage materials do not provide the requisite combination of high energy density, high stability, easy handling, transportability and low cost. New hybrid solar thermal fuels, composed of photoswitchable molecules on rigid, low-mass nanostructures, transcend the physical limitations of molecular solar thermal fuels by introducing local sterically constrained environments in which interactions between chromophores can be tuned. We demonstrate this principle of a hybrid solar thermal fuel using azobenzene-functionalized carbon nanotubes. We show that, on composite bundling, the amount of energy stored per azobenzene more than doubles from 58 to 120 kJ mol-1, and the material also maintains robust cyclability and stability. Our results demonstrate that solar thermal fuels composed of molecule-nanostructure hybrids can exhibit significantly enhanced energy-storage capabilities through the generation of template-enforced steric strain.

  12. Thermal energy storage. [by means of chemical reactions

    Science.gov (United States)

    Grodzka, P. G.

    1975-01-01

    The principles involved in thermal energy storage by sensible heat, chemical potential energy, and latent heat of fusion are examined for the purpose of evolving selection criteria for material candidates in the low ( 0 C) and high ( 100 C) temperature ranges. The examination identifies some unresolved theoretical considerations and permits a preliminary formulation of an energy storage theory. A number of candidates in the low and high temperature ranges are presented along with a rating of candidates or potential candidates. A few interesting candidates in the 0 to 100 C region are also included. It is concluded that storage by means of reactions whose reversibility can be controlled either by product removal or by catalytic means appear to offer appreciable advantages over storage with reactions whose reversability cannot be controlled. Among such advantages are listed higher heat storage capacities and more favorable options regarding temperatures of collection, storage, and delivery. Among the disadvantages are lower storage efficiencies.

  13. Wind energy as a significant source of electricity for the United States

    International Nuclear Information System (INIS)

    This paper discusses wind energy and its potential to significantly impact the generation of electricity within the US. The principles and the equipment used to convert wind energy to electricity are described, as is the status of current technology. Markets and production projections are given. There is discussion of the advances required to reduce the selling cost of electricity generated from the wind from today's price of about $0.05 per kilowatt-hour to full cost-competitiveness with gas- and coal-based electricity

  14. Energy use and energy intensity of the U.S. chemical industry

    Energy Technology Data Exchange (ETDEWEB)

    Worrell, E.; Phylipsen, D.; Einstein, D.; Martin, N.

    2000-04-01

    The U.S. chemical industry is the largest in the world, and responsible for about 11% of the U.S. industrial production measured as value added. It consumes approximately 20% of total industrial energy consumption in the U.S. (1994), and contributes in similar proportions to U.S. greenhouse gas emissions. Surprisingly, there is not much information on energy use and energy intensity in the chemical industry available in the public domain. This report provides detailed information on energy use and energy intensity for the major groups of energy-intensive chemical products. Ethylene production is the major product in terms of production volume of the petrochemical industry. The petrochemical industry (SIC 2869) produces a wide variety of products. However, most energy is used for a small number of intermediate compounds, of which ethylene is the most important one. Based on a detailed assessment we estimate fuel use for ethylene manufacture at 520 PJ (LHV), excluding feedstock use. Energy intensity is estimated at 26 GJ/tonne ethylene (LHV), excluding feedstocks.The nitrogenous fertilizer production is a very energy intensive industry, producing a variety of fertilizers and other nitrogen-compounds. Ammonia is the most important intermediate chemical compound, used as basis for almost all products. Fuel use is estimated at 268 PJ (excluding feedstocks) while 368 PJ natural gas is used as feedstock. Electricity consumption is estimated at 14 PJ. We estimate the energy intensity of ammonia manufacture at 39.3 GJ/tonne (including feedstocks, HHV) and 140 kWh/tonne, resulting in a specific primary energy consumption of 40.9 GJ/tonne (HHV), equivalent to 37.1 GJ/tonne (LHV). Excluding natural gas use for feedstocks the primary energy consumption is estimated at 16.7 GJ/tonne (LHV). The third most important product from an energy perspective is the production of chlorine and caustic soda. Chlorine is produced through electrolysis of a salt-solution. Chlorine production is

  15. ANALYSIS OF THERMAL-CHEMICAL CHARACTERISTICS OF BIOMASS ENERGY PELLETS

    Directory of Open Access Journals (Sweden)

    Zorica Gluvakov

    2014-09-01

    Full Text Available In modern life conditions, when emphasis is on environmental protection and sustainable development, fuels produced from biomass are increasingly gaining in importance, and it is necessary to consider the quality of end products obtained from biomass. Based on the existing European standards, collected literature and existing laboratory methods, this paper presents results of testing individual thermal - chemical properties of biomass energy pellets after extrusion and cooling the compressed material. Analysing samples based on standard methods, data were obtained on the basis of which individual thermal-chemical properties of pellets were estimated. Comparing the obtained results with the standards and literature sources, it can be said that moisture content, ash content and calorific values are the most important parameters for quality analysis which decide on applicability and use-value of biomass energy pellets, as biofuel. This paper also shows the impact of biofuels on the quality of environmental protection. The conclusion provides a clear statement of quality of biomass energy pellets.

  16. The perceptual significance of high-frequency energy in the human voice

    Science.gov (United States)

    Monson, Brian B.; Hunter, Eric J.; Lotto, Andrew J.; Story, Brad H.

    2014-01-01

    While human vocalizations generate acoustical energy at frequencies up to (and beyond) 20 kHz, the energy at frequencies above about 5 kHz has traditionally been neglected in speech perception research. The intent of this paper is to review (1) the historical reasons for this research trend and (2) the work that continues to elucidate the perceptual significance of high-frequency energy (HFE) in speech and singing. The historical and physical factors reveal that, while HFE was believed to be unnecessary and/or impractical for applications of interest, it was never shown to be perceptually insignificant. Rather, the main causes for focus on low-frequency energy appear to be because the low-frequency portion of the speech spectrum was seen to be sufficient (from a perceptual standpoint), or the difficulty of HFE research was too great to be justifiable (from a technological standpoint). The advancement of technology continues to overcome concerns stemming from the latter reason. Likewise, advances in our understanding of the perceptual effects of HFE now cast doubt on the first cause. Emerging evidence indicates that HFE plays a more significant role than previously believed, and should thus be considered in speech and voice perception research, especially in research involving children and the hearing impaired. PMID:24982643

  17. The perceptual significance of high-frequency energy in the human voice.

    Science.gov (United States)

    Monson, Brian B; Hunter, Eric J; Lotto, Andrew J; Story, Brad H

    2014-01-01

    While human vocalizations generate acoustical energy at frequencies up to (and beyond) 20 kHz, the energy at frequencies above about 5 kHz has traditionally been neglected in speech perception research. The intent of this paper is to review (1) the historical reasons for this research trend and (2) the work that continues to elucidate the perceptual significance of high-frequency energy (HFE) in speech and singing. The historical and physical factors reveal that, while HFE was believed to be unnecessary and/or impractical for applications of interest, it was never shown to be perceptually insignificant. Rather, the main causes for focus on low-frequency energy appear to be because the low-frequency portion of the speech spectrum was seen to be sufficient (from a perceptual standpoint), or the difficulty of HFE research was too great to be justifiable (from a technological standpoint). The advancement of technology continues to overcome concerns stemming from the latter reason. Likewise, advances in our understanding of the perceptual effects of HFE now cast doubt on the first cause. Emerging evidence indicates that HFE plays a more significant role than previously believed, and should thus be considered in speech and voice perception research, especially in research involving children and the hearing impaired. PMID:24982643

  18. The perceptual significance of high-frequency energy in the human voice

    Directory of Open Access Journals (Sweden)

    Brian B. Monson

    2014-06-01

    Full Text Available While human vocalizations generate acoustical energy at frequencies up to (and beyond 20 kHz, the energy at frequencies above about 5 kHz has traditionally been neglected in speech perception research. The intent of this paper is to review (1 the historical reasons for this research trend and (2 the work that continues to elucidate the perceptual significance of high-frequency energy (HFE in speech and singing. The historical and physical factors reveal that, while HFE was believed to be unnecessary and/or impractical for applications of interest, it was never shown to be perceptually insignificant. Rather, the main causes for focus on low-frequency energy appear to be because the low-frequency portion of the speech spectrum was seen to be sufficient (from a perceptual standpoint, or the difficulty of HFE research was too great to be justifiable (from a technological standpoint. The advancement of technology continues to overcome concerns stemming from the latter reason. Likewise, advances in our understanding of the perceptual effects of HFE now cast doubt on the first cause. Emerging evidence indicates that HFE plays a more significant role than previously believed, and should thus be considered in speech and voice perception research, especially in research involving children and the hearing impaired.

  19. 76 FR 65579 - Certain High Production Volume Chemicals; Test Rule and Significant New Use Rule; Fourth Group of...

    Science.gov (United States)

    2011-10-21

    ... bioconcentration factor (BCF) of about 1,000 (Refs. 17, 29, and 30). A chemical substance with a fish BCF value of... are required to show photographic identification, pass through a metal detector, and sign the EPA... there were no other factors that removed the chemical substances from the scope of the HPV Challenge....

  20. Quarterly Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: January-March 1998

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1999-03-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period January-March 1998. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within nine major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Biotechnology, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnology Research, and Molecular Studies.

  1. The origin of the chemical profiles of fungal symbionts and their significance for nestmate recognition in Acromyrmex leaf-cutting ants

    DEFF Research Database (Denmark)

    Richard, Freddie-Jeanne; Poulsen, Michael; Hefetz, Abraham;

    2007-01-01

    less aggression when they are later introduced into that colony. It appears, therefore, that fungus gardens are an independent and significant source of chemical compounds, potentially contributing a richer and more abundant blend of recognition cues to the colony ¿gestalt¿ than the innate chemical...

  2. Accelerator driven reactors, - the significance of the energy distribution of spallation neutrons on the neutron statistics

    International Nuclear Information System (INIS)

    distribution of the spallation neutrons leads to second moments that differ significantly from the ones calculated with the average energy distribution only. With the most realistic model of the energy distributions, the second moment of the number of fissions was underestimated with 12-16%

  3. Understanding and tuning nanostructured materials for chemical energy conversion

    Science.gov (United States)

    Jian, Guoqiang

    The conversion of energy that employs chemical reaction is termed chemical energy conversion. In my dissertation, I have focused on chemical energy conversion systems involving energetic materials and lithium ion batteries, where performance is strongly dependent on the properties of materials and their architecture. The objective of this study is to enhance our understanding and tuning of nanostructured materials that might find application toward energetic materials and electrode materials in lithium ion batteries. Rapid heating diagnostics tools, i.e. temperature-jump techniques, have been used to study the ignition of aluminum nanoparticles, nanothermite reaction mechanism and metal oxides nanoparticles decomposition under rapid heating conditions (˜105-106 K/s). Time-resolved mass spectra results support the hypothesis that Al containing species diffuse outwards through the oxide shell. Low effective activation energies were found for metal oxides nanoparticles decomposition at high heating rates, implying the mass transfer control at high heating rates. The role of oxygen release from oxidizer in nanothermite reactions have been examined for several different systems, including some using microsized oxidizer (i.e., nano-Al/micro-I 2O5). In particular, for periodate based nanothermites, direct evidence from high heating rate SEM and mass spectrometry results support that direct gas phase oxygen release from oxidizer decomposition is critical in its ignition and combustion. Efforts have also been made to synthesize nanostructured materials for nanoenergetic materials and lithium ion batteries applications. Hollow CuO spheres were synthesized by aerosol spray pyrolysis, employing a gas blowing mechanism for the formation of hollow structure during aerosol synthesis. The materials synthesized as oxidizers in nanothermite demonstrated superior performance, and of particular note, periodate salts based nanothermite demonstrated the best gas generating performance

  4. A graph of dark energy significance on different spatial and mass scales

    CERN Document Server

    Teerikorpi, P; Nurmi, P; Chernin, A D; Einasto, M; Valtonen, M; Byrd, G

    2015-01-01

    The current cosmological paradigm sees the formation and evolution of the cosmic large-scale structure as governed by the gravitational attraction of the Dark Matter (DM) and the repulsion of the Dark Energy (DE). We characterize the relative importance of uniform and constant dark energy, as given by the Lambda term in the standard LCDM cosmology, in galaxy systems of different scales, from groups to superclusters. An instructive "Lambda significance graph" is introduced where the matter-DE density ratio /rho_Lambda for different galaxy systems is plotted against the radius R. This presents gravitation and DE dominated regions and shows directly the zero velocity radius, the zero-gravity radius, and the Einstein-Straus radius for any fixed value of mass. Example galaxy groups and clusters from the local universe illustrate the use of the Lambda significance graph. These are generally located deep in the gravity-dominated region /rho_Lambda > 2, being virialized. Extended clusters and main bodies of superclus...

  5. Scaling of surface-plasma reactors with a significantly increased energy density for NO conversion

    International Nuclear Information System (INIS)

    Highlights: ► An electrical shield is found to decouple surface-plasmas in neighboring chambers. ► The shield increases the power density in the plasma. ► The shield allows operating chambers in parallel without loss of efficiency. ► Removal of nitric oxide from air is demonstrated. - Abstract: Comparative studies revealed that surface plasmas developing along a solid–gas interface are significantly more effective and energy efficient for remediation of toxic pollutants in air than conventional plasmas propagating in air. Scaling of the surface plasma reactors to large volumes by operating them in parallel suffers from a serious problem of adverse effects of the space charges generated at the dielectric surfaces of the neighboring discharge chambers. This study revealed that a conductive foil on the cathode potential placed between the dielectric plates as a shield not only decoupled the discharges, but also increased the electrical power deposited in the reactor by a factor of about forty over the electrical power level obtained without shielding and without loss of efficiency for NO removal. The shield had no negative effect on efficiency, which is verified by the fact that the energy costs for 50% NO removal were about 60 eV/molecule and the energy constant, kE, was about 0.02 L/J in both the shielded and unshielded cases.

  6. Chemical energy in an introductory physics course for the life sciences

    OpenAIRE

    Dreyfus, Benjamin W.; Gouvea, Julia; Geller, Benjamin D.; Sawtelle, Vashti; Turpen, Chandra; Redish, Edward F.

    2013-01-01

    Energy is a complex idea that cuts across scientific disciplines. For life science students, an approach to energy that incorporates chemical bonds and chemical reactions is better equipped to meet the needs of life sciences students than a traditional introductory physics approach that focuses primarily on mechanical energy. We present a curricular sequence, or thread, designed to build up students' understanding of chemical energy in an introductory physics course for the life sciences. Thi...

  7. Analysis and modelling of the energy consumption of chemical batch plants

    Energy Technology Data Exchange (ETDEWEB)

    Bieler, P.S.

    2004-07-01

    This report for the Swiss Federal Office of Energy (SFOE) describes two different approaches for the energy analysis and modelling of chemical batch plants. A top-down model consisting of a linear equation based on the specific energy consumption per ton of production output and the base consumption of the plant is postulated. The model is shown to be applicable to single and multi-product batches for batch plants with constant production mix and multi-purpose batch plants in which only similar chemicals are produced. For multipurpose batch plants with highly varying production processes and changing production mix, the top-down model produced inaccurate results. A bottom-up model is postulated for such plants. The results obtained are discussed that show that the electricity consumption for infrastructure equipment was significant and responsible for about 50% of total electricity consumption. The specific energy consumption for the different buildings was related to the degree of automation and the production processes. Analyses of the results of modelling are presented. More detailed analyses of the energy consumption of this apparatus group show that about 30 to 40% of steam energy is lost and thus a large potential for optimisation exists. Various potentials for making savings, ranging from elimination of reflux conditions to the development of a new heating/cooling-system for a generic batch reactor, are identified.

  8. Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division, April--June 1997

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1998-06-01

    The Chemical and Energy Research Section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within six major areas of research: Hot Cell Operations, Process Chemistry and thermodynamics, Separations and Materials Synthesis, Solution Thermodynamics, biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information.

  9. LongTerm Energy Efficiency Analysis Requires Solid Energy Statistics: The case of the German Basic Chemical Industry

    NARCIS (Netherlands)

    Saygin, D.; Worrell, E.; Tam, C.; Trudeau, N.; Gielen, D.J.; Weiss, M.; Patel, M.K.

    2012-01-01

    Analyzing the chemical industry’s energy use is challenging because of the sector’s complexity and the prevailing uncertainty in energy use and production data. We develop an advanced bottom-up model (PIE-Plus) which encompasses the energy use of the 139 most important chemical processes. We apply t

  10. Significant release of shear energy of the North Korean nuclear test on February 12, 2013

    Science.gov (United States)

    Barth, Andreas

    2014-07-01

    On February 12, 2013 the Democratic People's Republic of Korea (DPRK) carried out an announced nuclear test, which was the third after tests conducted in 2006 and 2009. An important task in discriminating a man-made explosion and a natural tectonic earthquake is the analysis of seismic waveforms. To determine the isotropic and non-isotropic characteristics of the detonation source, I invert long-period seismic data for the full seismic moment tensor to match the observed seismic signals by synthetic waveforms based on a 3D Earth model. Here, I show that the inversion of long-period seismic data of the 2013 test reveals a clear explosive (isotropic) component combined with a significant release of shear energy by the double-couple part of the moment tensor. While the isotropic part of the nuclear test in 2009 was similar to that in 2013, the double-couple part was lower by a factor of 0.55 compared to the explosion in 2013. Moreover, the ratio of the isotropic seismic moments of the 2013 and 2009 nuclear tests is 1.4 ± 0.1 and lower than published estimations of the yield ratio, which indicates the importance of considering the release of shear energy. The determined orientation of the double-couple fault plane is parallel to the dominating geologic fault structures NNE-SSW to NE-SW, but the calculated normal faulting mechanism does not correspond to the general tectonic strike-slip regime. Thus, explanations for the enhanced release of shear energy might be induced dip-slip motion pre-stressed by the previous test or near source damaging effects due to a changed containment of the nuclear explosion.

  11. Statistical Significance of Small Scale Anisotropy in Arrival Directions of Ultra-High Energy Cosmic Rays

    CERN Document Server

    Yoshiguchi, H; Sato, K; Yoshiguchi, Hiroyuki; Nagataki, Shigehiro; Sato, Katsuhiko

    2004-01-01

    Recently, the High Resolution Fly's Eye (HiRes) experiment claims that there is no small scale anisotropy in the arrival distribution of ultra-high energy cosmic rays (UHECRs) above $E>10^{19}$ eV contrary to the Akeno Giant Air Shower Array (AGASA) observation. In this paper, we discuss the statistical significance of this discrepancy between the two experiments. We calculate arrival distribution of UHECRs above $10^{19}$ eV predicted by the source models constructed using the Optical Redshift Survey galaxy sample. We apply the new method developed by us for calculating arrival distribution in the presence of the galactic magnetic field. The great advantage of this method is that it enables us to calculate UHECR arrival distribution with lower energy ($\\sim 10^{19}$ eV) than previous studies within reasonable time by following only the trajectories of UHECRs actually reaching the earth. It has been realized that the small scale anisotropy observed by the AGASA can be explained with the source number density ...

  12. The visualization of surgical smoke produced by energy delivery devices: significance and effectiveness of evacuation systems

    Science.gov (United States)

    de Boorder, Tjeerd; Verdaasdonk, Rudolf; Klaessens, John

    2007-02-01

    Devices delivering energy to biological tissues (eg lasers, RF and ultrasound) can induce surgical smoke consisting of particles, vapor, gasses and aerosols. Besides interfering with the view of the surgeon, the smoke is a risk for the health of both the users and patients. In literature, it has been shown that surgical smoke can contain carcinogenic and harmful biological agents. However, the impact on health of the users and patients is widely debated. The use of smoke evacuation systems in the OR is usually governed by economical reason instead of safety issues. A special image enhancement technique is used to study the behavior of smoke and aerosols and the effectiveness of smoke evacuation systems. A back scatter illumination technique using 1 μs light flashes at video rate was applied to image the smoke production of various surgical devices without and with smoke evacuation while ablating biological tissues. The effectiveness of various smoke evacuation devices and strategies were compared. The ablative thermal devices produced smoke but also aerosols. If the thermal energy was delivered in high peak pulses, the presence of aerosols was more significant. Ultrasound based devices produce mainly aerosols. The distance to the target, the opening of the evacuation nozzle and the dimension of aerosols were leading for the effectiveness of the smoke evacuation. The smoke visualization technique has proven an effective tool for study the effectiveness of smoke and aerosols evacuation. The results can contribute to the necessity to use evacuation systems in the OR.

  13. Heat storage in forest biomass significantly improves energy balance closure particularly during stable conditions

    Directory of Open Access Journals (Sweden)

    A. Lindroth

    2009-08-01

    Full Text Available Temperature measurements in trunks and branches in a mature ca. 100 years-old mixed pine and spruce forest in central Sweden were used to estimate the heat storage in the tree biomass. The estimated heat flux in the sample trees and data on biomass distributions were used to scale up to stand level biomass heat fluxes. The rate of change of sensible and latent heat storage in the air layer below the level of the flux measurements was estimated from air temperature and humidity profile measurements and soil heat flux was estimated from heat flux plates and soil temperature measurements. The fluxes of sensible and latent heat from the forest were measured with an eddy covariance system in a tower. The analysis was made for a two-month period in summer of 1995. The tree biomass heat flux was the largest of the estimated storage components and varied between 40 and −35 W m−2 on summer days with nice weather. Averaged over two months the diurnal maximum of total heat storage was 45 W m−2 and the minimum was −35 W m−2. The soil heat flux and the sensible heat storage in air were out of phase with the biomass flux and they reached maximum values that were about 75% of the maximum of the tree biomass heat storage. The energy balance closure improved significantly when the total heat storage was added to the turbulent fluxes. The slope of a regression line with sum of fluxes and storage as independent and net radiation as dependent variable, increased from 0.86 to 0.95 for half-hourly data and the scatter was also reduced. The most significant finding was, however, that during nights with strongly stable conditions when the sensible heat flux dropped to nearly zero, the total storage matched the net radiation nearly perfectly. Another interesting result was that the mean energy imbalance started to increase when the Richardson number became more negative than ca. −0.1. In fact, the largest energy deficit

  14. Long-term energy efficiency analysis requires solid energy statistics: The case of the German basic chemical industry

    International Nuclear Information System (INIS)

    Analyzing the chemical industry’s energy use is challenging because of the sector’s complexity and the prevailing uncertainty in energy use and production data. We develop an advanced bottom-up model (PIE-Plus) which encompasses the energy use of the 139 most important chemical processes. We apply this model in a case study to analyze the German basic chemical industry’s energy use and energy efficiency improvements in the period between 1995 and 2008. We compare our results with data from the German Energy Balances and with data published by the International Energy Agency (IEA). We find that our model covers 88% of the basic chemical industry’s total final energy use (including non-energy use) as reported in the German Energy Balances. The observed energy efficiency improvements range between 2.2 and 3.5% per year, i.e., they are on the higher side of the values typically reported in literature. Our results point to uncertainties in the basic chemical industry’s final energy use as reported in the energy statistics and the specific energy consumption values. More efforts are required to improve the quality of the national and international energy statistics to make them useable for reliable monitoring of energy efficiency improvements of the chemical industry. -- Highlights: ► An advanced model was developed to estimate German chemical industry’s energy use. ► For the base year (2000), model covers 88% of the sector’s total final energy use. ► Sector’s energy efficiency improved between 2.2 and 3.5%/yr between 1995 and 2008. ► Improved energy statistics are required for accurate monitoring of improvements.

  15. Effects of chemical fuel composition on energy generation from thermopower waves

    International Nuclear Information System (INIS)

    Thermopower waves, which occur during combustion within hybrid structures formed from nanomaterials and chemical fuels, result in a self-propagating thermal reaction and concomitantly generate electrical energy from the acceleration of charge carriers along the nanostructures. The hybrid structures for thermopower waves are composed of two primary components: the core thermoelectric material and the combustible fuel. So far, most studies have focused on investigating various nanomaterials for improving energy generation. Herein, we report that the composition of the chemical fuel used has a significant effect on the power generated by thermopower waves. Hybrid nanostructures consisting of mixtures of picric acid and picramide with sodium azide were synthesized and used to generate thermopower waves. A maximum voltage of ∼2 V and an average peak specific power as high as 15 kW kg−1 were obtained using the picric acid/sodium azide/multiwalled carbon nanotubes (MWCNTs) array composite. The average reaction velocity and the output voltage in the case of the picric acid/sodium azide were 25 cm s−1 and 157 mV, while they were 2 cm s−1 and 3 mV, in the case of the picramide/sodium azide. These marked differences are attributable to the chemical and structural differences of the mixtures. Mixing picric acid and sodium azide in deionized water resulted in the formation of 2,4,6-trinitro sodium phenoxide and hydrogen azide (H-N3), owing to the exchange of H+ and Na+ ions, as well as the formation of fiber-like structures, because of benzene π stacking. The negative enthalpy of formation of the new compounds and the fiber-like structures accelerate the reaction and increase the output voltage. Elucidating the effects of the composition of the chemical fuel used in the hybrid nanostructures will allow for the control of the combustion process and help optimize the energy generated from thermopower waves, furthering the development of thermopower waves as an energy

  16. Effects of chemical fuel composition on energy generation from thermopower waves

    Science.gov (United States)

    Yeo, Taehan; Hwang, Hayoung; Jeong, Dong-Cheol; Lee, Kang Yeol; Hong, Jongsup; Song, Changsik; Choi, Wonjoon

    2014-11-01

    Thermopower waves, which occur during combustion within hybrid structures formed from nanomaterials and chemical fuels, result in a self-propagating thermal reaction and concomitantly generate electrical energy from the acceleration of charge carriers along the nanostructures. The hybrid structures for thermopower waves are composed of two primary components: the core thermoelectric material and the combustible fuel. So far, most studies have focused on investigating various nanomaterials for improving energy generation. Herein, we report that the composition of the chemical fuel used has a significant effect on the power generated by thermopower waves. Hybrid nanostructures consisting of mixtures of picric acid and picramide with sodium azide were synthesized and used to generate thermopower waves. A maximum voltage of ˜2 V and an average peak specific power as high as 15 kW kg-1 were obtained using the picric acid/sodium azide/multiwalled carbon nanotubes (MWCNTs) array composite. The average reaction velocity and the output voltage in the case of the picric acid/sodium azide were 25 cm s-1 and 157 mV, while they were 2 cm s-1 and 3 mV, in the case of the picramide/sodium azide. These marked differences are attributable to the chemical and structural differences of the mixtures. Mixing picric acid and sodium azide in deionized water resulted in the formation of 2,4,6-trinitro sodium phenoxide and hydrogen azide (H-N3), owing to the exchange of H+ and Na+ ions, as well as the formation of fiber-like structures, because of benzene π stacking. The negative enthalpy of formation of the new compounds and the fiber-like structures accelerate the reaction and increase the output voltage. Elucidating the effects of the composition of the chemical fuel used in the hybrid nanostructures will allow for the control of the combustion process and help optimize the energy generated from thermopower waves, furthering the development of thermopower waves as an energy source.

  17. Technology Roadmap: Energy and GHG reductions in the chemical industry via catalytic processes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    The chemical industry is a large energy user; but chemical products and technologies also are used in a wide array of energy saving and/or renewable energy applications so the industry has also an energy saving role. The chemical and petrochemical sector is by far the largest industrial energy user, accounting for roughly 10% of total worldwide final energy demand and 7% of global GHG emissions. The International Council of Chemical Associations (ICCA) has partnered with the IEA and DECHEMA (Society for Chemical Engineering and Biotechnology) to describe the path toward further improvements in energy efficiency and GHG reductions in the chemical sector. The roadmap looks at measures needed from the chemical industry, policymakers, investors and academia to press on with catalysis technology and unleash its potential around the globe. The report uncovers findings and best practice opportunities that illustrate how continuous improvements and breakthrough technology options can cut energy use and bring down greenhouse gas (GHG) emission rates. Around 90% of chemical processes involve the use of catalysts – such as added substances that increase the rate of reaction without being consumed by it – and related processes to enhance production efficiency and reduce energy use, thereby curtailing GHG emission levels. This work shows an energy savings potential approaching 13 exajoules (EJ) by 2050 – equivalent to the current annual primary energy use of Germany.

  18. Single-collision studies of energy transfer and chemical reaction

    Energy Technology Data Exchange (ETDEWEB)

    Valentini, J.J. [Columbia Univ., New York, NY (United States)

    1993-12-01

    The research focus in this group is state-to-state dynamics of reaction and energy transfer in collisions of free radicals such as H, OH, and CH{sub 3} with H{sub 2}, alkanes, alcohols and other hydrogen-containing molecules. The motivation for the work is the desire to provide a detailed understanding of the chemical dynamics of prototype reactions that are important in the production and utilization of energy sources, most importantly in combustion. The work is primarily experimental, but with an important and growing theoretical/computational component. The focus of this research program is now on reactions in which at least one of the reactants and one of the products is polyatomic. The objective is to determine how the high dimensionality of the reactants and products differentiates such reactions from atom + diatom reactions of the same kinematics and energetics. The experiments use highly time-resolved laser spectroscopic methods to prepare reactant states and analyze the states of the products on a single-collision time scale. The primary spectroscopic tool for product state analysis is coherent anti-Stokes Raman scattering (CARS) spectroscopy. CARS is used because of its generality and because the extraction of quantum state populations from CARS spectra is straightforward. The combination of the generality and easy analysis of CARS makes possible absolute cross section measurements (both state-to-state and total), a particularly valuable capability for characterizing reactive and inelastic collisions. Reactant free radicals are produced by laser photolysis of appropriate precursors. For reactant vibrational excitation stimulated Raman techniques are being developed and implemented.

  19. Dietary Mannoheptulose Does Not Significantly Alter Daily Energy Expenditure in Adult Labrador Retrievers.

    Directory of Open Access Journals (Sweden)

    Leslie L McKnight

    Full Text Available Mannoheptulose (MH, a sugar found in avocados that inhibits glycolysis in vitro, has been preliminarily investigated as a novel food ingredient for dogs. This study aimed to determine the effects of dietary MH, delivered as an extract of un-ripened avocado, on energy expenditure (EE in healthy adult Labrador Retriever dogs (total of 12 dogs, 26.99 ± 0.634 kg, 4.9 ± 0.2 y. The study was a double-blind, cross-over with each dog receiving both dietary treatments, control (CON and MH (400 mg/kg of diet; 6 mg/kg BW, in random order. Resting and post-prandial (10 h EE and respiratory quotient (RQ were determined by indirect calorimetry (d 42. The following day, body composition was assessed using dual X-ray absorptiometry. Continuous activity monitoring was conducted using an Atical® accelerometer (d 43-47. A vastus lateralis muscle biopsy was obtained prior to the morning meal (d 49 and 4 h after consumption of their meal (d 56 to determine the protein content and phosphorylation of 5' adenosine monophosphate-activated protein kinase (AMPK. Diet did not affect body weight, resting EE or skeletal muscle AMPK phosphorylation. Dogs fed MH had significantly lower post-prandial RQ (p = 0.02 and ratio of fat to lean body mass (p = 0.02. Physical activity during light time periods (but not dark was lower in dogs fed MH (p < 0.05 during weekends, but not on weekdays. These results suggest that MH affects energy balance of adult dogs, but that these effects are not dose dependent and not due to physical activity.

  20. Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: July--September 1997

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1998-07-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period July--September 1997. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within nine major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Biotechnology, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information.

  1. Agrice 1994-2000 - Activity report. Agriculture for chemicals and energy

    International Nuclear Information System (INIS)

    The emergence of new energy, chemicals and materials markets for agricultural products calls for an ongoing commitment to significant and stable funding for research. Even more importantly, these new markets also necessitate better coordination between the actors across the field, ranging from multidisciplinary research teams and agro-industrial companies to users in the petrochemicals, chemicals and materials sectors, and agricultural production. The need for this coordination is even greater today, in light of the key role that 'non-food' supply chains play in environmental protection: efforts to mitigate the greenhouse effect, reduction of VOC emissions, product safety and biodegradability, rational farming practices, etc. With these ends in mind the scientific interest group AGRICE- Agriculture for Chemicals and Energy- was created in France in 1994 by government bodies and eight partners. Today AGRICE includes the following members: the Institut Francais du Petrole (IFP), the Institut National de Recherche Agronomique (INRA), the Centre National de Recherche Scientifique (CNRS) and the Agence de l'Environnement et de la Maitrise de l'Energie (ADEME), professional organisations in oilseeds (ONIDOL), grains (AGPB) and beets (CGB), AVENTIS, TOTAL FINA ELF, LIMAGRAIN and EDF, the French ministries of Agriculture, Industry, Research, and Environment. AGRICE was founded for a six-year renewable term, and its management entrusted to ADEME. The group has worked to develop significant collaborative efforts across Europe, notably through the European Renewable Resources and Materials Association (ERRMA). AGRICE is due to be renewed with a broader base of partners in 2001. This report presents: 1 - the AGRICE profile, scope of activity (Biofuels vehicles (Ester/Oils, Ethanol/Ether) and non-vehicles (Energy crops, Processes), Biomolecules (Lubricants, Surfactants, Solvents, Other biomolecules), Biomaterials (Biopolymers, Agro-materials)), Financial report 1994

  2. The bioliq {sup registered} bioslurry gasification process for the production of biosynfuels, organic chemicals, and energy

    Energy Technology Data Exchange (ETDEWEB)

    Dahmen, Nicolaus; Henrich, Edmund; Dinjus, Eckhard; Weirich, Friedhelm [Karlsruhe Institute of Technology (KIT), Eggenstein-Leopoldshafen (Germany). Inst. of Catalysis Research and Technology

    2012-12-15

    Biofuels may play a significant role in regard to carbon emission reduction in the transportation sector. Therefore, a thermochemical process for biomass conversion into synthetic chemicals and fuels is being developed at the Karlsruhe Institute of Technology (KIT) by producing process energy to achieve a desirable high carbon dioxide reduction potential. In the bioliq process, lignocellulosic biomass is first liquefied by fast pyrolysis in distributed regional plants to produce an energy-dense intermediate suitable for economic transport over long distances. Slurries of pyrolysis condensates and char, also referred to as biosyncrude, are transported to a large central gasification and synthesis plant. The bioslurry is preheated and pumped into a pressurized entrained flow gasifier, atomized with technical oxygen, and converted at > 1,200 C to an almost tar-free, low-methane syngas. Syngas - a mixture of CO and H2 - is a well-known versatile intermediate for the selectively catalyzed production of various base chemicals or synthetic fuels. At KIT, a pilot plant has been constructed together with industrial partners to demonstrate the process chain in representative scale. The process data obtained will allow for process scale-up and reliable cost estimates. In addition, practical experience is gained. The paper describes the background, principal technical concepts, and actual development status of the bioliq process. It is considered to have the potential for worldwide application in large scale since any kind of dry biomass can be used as feedstock. Thus, a significant contribution to a sustainable future energy supply could be achieved.

  3. Physico-chemical investigation of some areas of fundamental significance to biophysics. Annual report, 1978-1979

    International Nuclear Information System (INIS)

    Work in progress includes: analyzing the lowest-energy Rydberg transitions of the alkyl halides; decomposition of a spectroscopic signal S into a system of bands; luminescence of aqueous systems; a study of the effects of small molecules on hydrogen bonding via glass transitions in ethanol; Rydberg/intravalence mixing in the S2 state of azulene; ultraviolet photoelectron spectroscopy of carbonyls; and multi-photon processes

  4. Finding of no significant impact for the State Energy Conservation Program

    International Nuclear Information System (INIS)

    The Department of Energy (DOE) has prepared a Programmatic Environmental Assessment (PEA), DOE/EA 1068, to assess the environmental impacts associated with the State Energy Conservation Program (SECP). DOE previously funded SECP projects under the Energy Policy and Conservation Act of 1975 (EPCA). The State Energy Efficiency Programs Improvements Act of 1990 (SEEPIA) and the Energy Policy Act of 1992 (EPACT) amended EPCA to broaden the range of state initiatives qualifying for Federal assistance under the SECP. The PEA presents a general analysis of the potential environmental effects associated with broad types of projects that can be funded under the SECP. It does not analyze specific environmental effects or alternatives associated with individual energy conservation, energy efficiency, and renewable energy projects. Individual actions are to be evaluated in detail on a project-by-project basis to determine whether their impacts fall within the bounding analysis of the impacts analyzed in the SECP PEA

  5. Chemical and physical characteristics of asbestos from north Pakistan and its significance in the promotion of asbestosis

    International Nuclear Information System (INIS)

    Studies of environmental geology are limited in Pakistan. Asbestos has been mined since early 70s around Peshawar valley but its role on environmental degradation was never regarded a concern until 1983. This study has been carried out to identify the carcinogenicity due to asbestos from the Sakhakot Qila Ultramafic Complex around Peshawar valley on the basis of chemical and physical features of the available asbestos minerals. Electron microprobe data (SiO/sub 2/=51.69% Al/sub 2/O/sub 3/=1.33%, FeO=1.33%, CaO=0.06%, XRD data (d=7.3-8.41, 1=400-100) and petrographic observation classify these asbestos minerals as chrysotile, antigorte and tremolite, indicate these to be carrying sufficient inhalation properties. Enhanced occurrences of allergies of lungs, eyes and skin have already been noted in the surrounding of the local mines and relevant industries in the area. Some of the important recommendations suggested for mitigation of asbestosis and other related ailments in the light of the data obtained are: adoption of ventilation and water spraying procedures in all processes of mining, transportation and industrial use of asbestos; personal protection of labor and skilled worker; restriction on use of asbestos in the manufacturing of talcum powder awareness training and health and safety monitoring of the employees and implementation of the international compensation laws. (author)

  6. Energy Certificate - Energy Performance Certificate for Buildings as Significant Support to Reducing Consumption Intensity in Croatia by 2050

    International Nuclear Information System (INIS)

    Since Energy Efficiency Certificate, as a certificate of energy efficiency in building, is a part of the DIRECTIVE 2002/91/EC on the energy performance of buildings and can be linked to the DIRECTIVE 2006/32/EG on energy end-use efficiency and energy services and to the Technical regulation of the Republic of Croatia about rational use of heath energy in the buildings, these are shown briefly and their correlation is pointed out. Activities for the joint European energy policy are listed: Green Book of the EU Commission for the joint European energy policy, Sustainable Energy Paths for Europe - Energy Paths Horizon 2050 and the programme Intelligent Energy in Europe (2003-2006). Issues of the Energy Efficiency Certificate are elaborated in detail, while the accent is on certification, not only for buildings, but also for house energy techniques and the class of energy sustainability. The advantages of the introduction of Energy Certificates are shown for the real estate market, as well as for the users. On the example of Austria, one of the EU leaders in introducing of sustainable energy policy, the issues linked to the introduction of Energy Efficiency Certificate are shown.(author)

  7. Optimising energy recovery and use of chemicals, resources and materials in modern waste-to-energy plants.

    Science.gov (United States)

    De Greef, J; Villani, K; Goethals, J; Van Belle, H; Van Caneghem, J; Vandecasteele, C

    2013-11-01

    Due to ongoing developments in the EU waste policy, Waste-to-Energy (WtE) plants are to be optimized beyond current acceptance levels. In this paper, a non-exhaustive overview of advanced technical improvements is presented and illustrated with facts and figures from state-of-the-art combustion plants for municipal solid waste (MSW). Some of the data included originate from regular WtE plant operation - before and after optimisation - as well as from defined plant-scale research. Aspects of energy efficiency and (re-)use of chemicals, resources and materials are discussed and support, in light of best available techniques (BAT), the idea that WtE plant performance still can be improved significantly, without direct need for expensive techniques, tools or re-design. In first instance, diagnostic skills and a thorough understanding of processes and operations allow for reclaiming the silent optimisation potential. PMID:23810322

  8. Significance of anaerobic digestion as a source of clean energy in wastewater treatment plants

    International Nuclear Information System (INIS)

    Highlights: • Between 39% and 79% of WWTP energy requirements could be fulfilled by the biogas produced. • Payback period of a biogas CHP engine is <2 years if energy price is ⩾216 € kJ−1. • 34% of the wastewater energy content is recovered into biogas. • Elemental composition is a good tool to estimate energy content of WWTP streams. - Abstract: Nowadays, energy consumption is one of the major concerns of wastewater treatment plants (WWTPs). Time ago, anaerobic digestion was usually implemented for sewage sludge stabilization but energy recovery optimization has recently gained importance. The energy balance of five WWTPs located in Catalonia revealed that depending on the configuration of the plant and its operation, between 39% and 76% of the total electric energy consumed in the WWTP could be supplied by the biogas produced. In the second part of this work, a carbon, nitrogen and sulphur flux analysis was carried out, together with an energy content evaluation for each stream in the WWTP. Results showed that 37% of the carbon found in the raw wastewater was removed during the active sludge process and 24% was transformed into biogas. The remaining carbon was found in the anaerobic dewatered sludge (22%) and in the treated water (19%). As a result, 34% of the initial energy was recovered in the form of biogas

  9. Geological subsurface will contribute significantly to the implementation of the energy policy towards renewables in Germany

    Science.gov (United States)

    Martens, Sonja; Kühn, Michael

    2015-04-01

    The demands to exploit the geological subsurface are increasing. In addition to the traditional production of raw materials such as natural gas and petroleum, or potable groundwater extraction the underground will most likely also be used to implement the climate and energy policy objectives in the context of the energy transition to renewables. These include the storage of energy from renewable sources (e.g. hydrogen and methane), the use of geothermal energy and possibly the long-term storage of carbon dioxide to reduce the release of greenhouse gases into the atmosphere. The presentation addresses the question which realistic contribution can be expected from the geo-resource subsurface for the energy revolution, the detachment of fossil and nuclear fuels as well as the reduction of CO2 emissions. The study of Henning and Palzer [1] that models the energy balance of the electricity and heat sector including all renewable energy converters, storage components and loads for a future German energy system shows that provision with 100% renewables is economically feasible by 2050. Based on their work, our estimates underline that already in 2015 more than 100% of the required methane storage capacities therein are available and more than 100% of the heat pump demands might be covered by shallow and deep geothermal energy production in the future. In addition we show that a newly developed energy storage system [2-3] could be applied to store 20-60% of the surplus energy from renewables expected for 2050 with integrated gas storage of methane and CO2. [1] Henning H-M, Palzer A (2014) A comprehensive model for the German electricity and heat sector in a future energy system with a dominant contribution from renewable energy technologies -- Part I: Methodology. Renewable and Sustainable Energy Reviews 30, 1003-1018. doi: 10.1016/j.rser.2013.09.012 [2] Kühn M, Nakaten N, Streibel M, Kempka T (2014) CO2 geological storage and utilization for a carbon neutral "power

  10. Significance of medium energy gamma ray astronomy in the study of cosmic rays

    Science.gov (United States)

    Fichtel, C. E.; Kniffen, D. A.; Thompson, D. J.; Bignami, G. F.; Cheung, C. Y.

    1975-01-01

    Medium energy (about 10 to 30 MeV) gamma ray astronomy provides information on the product of the galactic electron cosmic ray intensity and the galactic matter to which the electrons are dynamically coupled by the magnetic field. Because high energy (greater than 100 MeV) gamma ray astronomy provides analogous information for the nucleonic cosmic rays and the relevant matter, a comparison between high energy and medium energy gamma ray intensities provides a direct ratio of the cosmic ray electrons and nucleons throughout the galaxy. A calculation of gamma ray production by electron bremsstrahlung shows that: bremsstrahlung energy loss is probably not negligible over the lifetime of the electrons in the galaxy; and the approximate bremsstrahlung calculation often used previously overestimates the gamma ray intensity by about a factor of two. As a specific example, expected medium energy gamma ray intensities are calculated for the speral arm model.

  11. Significance of medium-energy gamma-ray astronomy in the study of cosmic rays

    Science.gov (United States)

    Fichtel, C. E.; Kniffen, D. A.; Thompson, D. J.; Bignami, G. F.; Cheung, C. Y.

    1976-01-01

    The paper examines the medium-energy (about 10-30 MeV) galactic gamma-ray radiation from primary and secondary electrons and calculates the expected gamma-ray distribution for the specific model of Bignami et al. (1975) on the assumption that the cosmic rays are correlated with the matter on the scale of galactic arms. The energy spectrum typical of regions near the galactic center indicates a dramatic shift from a predominantly cosmic-ray nucleonic mechanism at higher energies to a cosmic-ray electron mechanism at the lower energies. This provides a most important and direct means of probing the cosmic-ray electrons as a function of galactic position by making gamma-ray observations in the few to 40 MeV energy range. Medium-energy gamma-ray astronomy is shown to be a valuable tool in galactic research.

  12. Options for Water, Energy and Chemical Savings for Finitex, Cape Town

    DEFF Research Database (Denmark)

    Schneider, Zsig; Wenzel, Henrik

    An analysis of the options identified for saving of water, energy and chemicals was conducted at Finitex, Cape Town on the 18th October 2002. Cost savings were calculated from an estimation of the reduction in cost of water, energy and chemical usage associated with various interventions. Capital...

  13. Frost flowers on young Arctic sea ice: The climatic, chemical, and microbial significance of an emerging ice type

    DEFF Research Database (Denmark)

    Barber, D.; Ehn, J.; Pucko, M.;

    2014-01-01

    Ongoing changes in Arctic sea ice are increasing the spatial and temporal range of young sea ice types over which frost flowers can occur, yet the significance of frost flowers to ocean-sea ice-atmosphere exchange processes remains poorly understood. Frost flowers form when moisture from seawater...... formed. The new ice and frost flowers dramatically changed the radiative and thermal environment. The frost flowers were about 5°C colder than the brine surface, with an approximately linear temperature gradient from their base to their upper tips. Salinity and δ18O values indicated that frost flowers...

  14. Aluminium phosphate sulphate minerals (APS) associated with proterozoic unconformity-type uranium deposits: crystal-chemical characterisation and petrogenetic significance

    International Nuclear Information System (INIS)

    Aluminium phosphate sulfate minerals (APS) are particularly widespread and spatially associated with hydrothermal clay alteration in both the East Alligator River Uranium Field (Northern Territory, Australia) and the Athabasca basin (Saskatchewan, Canada), in the environment of proterozoic unconformity-related uranium deposits (URUD). The purpose of this study is both: 1) to characterize the nature and the origin of the APS minerals on both sides of the middle proterozoic unconformity between the overlying sandstones and the underlying metamorphic basement rocks that host the uranium ore bodies, 2) to improve our knowledge on the suitability of these minerals to indicate the paleo-conditions (redox, pH) at which the alteration processes relative to the uranium deposition operated. The APS minerals result from the interaction of oxidising and relatively acidic fluids with aluminous host rocks enriched in monazite. Several APS-bearing clay assemblages and APS crystal-chemistry have also been distinguished as a function of the distance from the uranium ore bodies or from the structural discontinuities which drained the hydrothermal solutions during the mineralisation event. One of the main results of this study is that the index mineral assemblages, used in the recent literature to describe the alteration zones around the uranium ore bodies, can be theoretically predicted by a set of thermodynamic calculations which simulate different steps of fluid-rock interaction processes related to a downward penetrating of hyper-saline, oxidizing and acidic diagenetic fluids through the lower sandstone units of the basins and then into the metamorphic basement rocks. The above considerations and the fact that APS with different crystal-chemical compositions crystallized in a range of fO2 and pH at which uranium can either be transported in solution or precipitated as uraninite in the host-rocks make these minerals not only good markers of the degree of alteration of the basement

  15. Excitation energy distribution between two photosystems in Porphyra yezoensis and its sig-nificance in photosynthesisevolution

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Comparative investigation on energy distribution between twophotosystems were carried out in the sporo- phytes and gametophytes of Porphyra yezoensis. By perfor- ming 77 K fluorescence spectra, we suggested that there probably existed a pathway for energy transfer from PSⅡ to PSⅠ to redistribute the absorbed energy in gametophytes, while no such a way or at minor level in sporophytes. Electron transfer inhibitor DCMU blocked the energy transfer from PSⅡ to PSⅠ in gametophytes, but no obvious effects on sporophytes. These indicated that excitation energy dis-tribution between two photosystems in gametophytes was more cooperative than that in sporophytes. These data in ontogenesis reflected the evolution process of photosynthetic organisms and supported the hypothesis of independent evolution of each photosystem.

  16. Towards consistent and reliable Dutch and international energy statistics for the chemical industry

    NARCIS (Netherlands)

    Neelis, M.L.; Pouwelse, J.W.

    2008-01-01

    Consistent and reliable energy statistics are of vital importance for proper monitoring of energy-efficiency policies. In recent studies, irregularities have been reported in the Dutch energy statistics for the chemical industry. We studied in depth the company data that form the basis of the energy

  17. Potential of best practice technology to improve energy efficiency in the global chemical and petrochemical sector

    NARCIS (Netherlands)

    Saygin, D.; Patel, M.K.; Worrell, E.; Tam, C.; Gielen, D.J.

    2011-01-01

    The chemical and petrochemical sector is by far the largest industrial energy user, accounting for 30% of the industry's total final energy use. However, due to its complexity its energy efficiency potential is not well understood. This article analyses the energy efficiency potential on a country l

  18. Cosmology with dark energy decaying through its chemical-potential contribution

    OpenAIRE

    Besprosvany, J.

    2007-01-01

    The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or radiation. When dominant, their energy densities tend asymptotically to a constant ratio, explaining today's dark energy-dark matter coincidence, and in agreement with supernova redshift data.

  19. Profitability of locations for wind energy utilization. Investigation of the significant influence parameters

    International Nuclear Information System (INIS)

    The jurisdiction for the designation of sites for wind energy requires that sufficient space was procured within the created sites for wind energy to achieve an exclusionary effect in the rest of the plan area of wind energy. This means that the designated areas must allow the economic operation of wind turbines. It is often not easy to adequately determine and assess the suitability of an area. The project economics of wind energy projects is dependent on the individual case, and there is no general guideline for estimating the decision of municipalities. In the case of allegations of so-called ''prevention plan'' against communities in which seemingly unsuitable areas have been identified the dispute is usually settled by court. This represents a considerable effort. At this point, the present investigation shall begin to prepare and carry out more detailed studies on the economics of wind energy sites, which can be used for orientation in the evaluation of possible identified areas for wind energy. For this purpose, the results of the power generation costs of wind energy projects from the Scientific accompanying report wind energy for EEG Progress Report will first used and collectively evaluated, what conclusions can be obtained based on these results for the profitability of locations. Based on the database, which was developed as part of the scientific opinion accompanying wind energy for EEG Progress Report, then a sensitivity analysis is carried out with regard to individual parameters of the economics of wind energy projects. This means individual factors within the sample locations are varied and analyzes the impact on the project economics. Thus, statements about can be taken, how limits for individual factors can be defined in terms of project economics.

  20. Computed Potential Energy Surfaces and Minimum Energy Pathway for Chemical Reactions

    Science.gov (United States)

    Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

    1994-01-01

    Computed potential energy surfaces are often required for computation of such observables as rate constants as a function of temperature, product branching ratios, and other detailed properties. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method with the Dunning correlation consistent basis sets to obtain accurate energetics, gives useful results for a number of chemically important systems. Applications to complex reactions leading to NO and soot formation in hydrocarbon combustion are discussed.

  1. Chemical composition of spinel from Uralian-Alaskan-type Mafic-Ultramafic complexes and its petrogenetic significance

    Science.gov (United States)

    Krause, J.; Brügmann, G. E.; Pushkarev, E. V.

    2011-02-01

    Uralian-Alaskan-type mafic-ultramafic complexes are recognized as a distinct class of intrusions regarding lithologic assemblage, mineral chemistry and petrogenetic setting. In the present study, we discuss new data on the distribution of major elements in minerals of the spinel group in rocks from Uralian-Alaskan-type complexes in the Ural Mountains, Russia. Cr-rich spinel (Cr2O3 = 20-53 wt%) in dunite with interstitial clinopyroxene and in wehrlite cumulates indicate that it reacted with interstitial liquid resulting in the progressive substitution of Al2O2 and Cr2O3 by Fe2O3 and TiO2. A distinct change in the spinel chemistry in dunite (Cr2O3 = 47-53 wt%), towards Al2O3- and Cr2O3-poor but Fe2O3-rich compositions monitors the onset of clinopyroxene fractionation in wehrlite (Cr2O3 = 15-35 wt%, Al2O3 = 1-8 wt%, Fe2O3 = 25-55 wt%). In more fractionated mafic rocks, the calculated initial composition of exsolved spinel traces the sustained crystallization of clinopyroxene by decreasing Cr2O3 and increasing FeO, Fe2O3 and fO2. Finally, the initiation of feldspar crystallization buffers the Al2O3 content in most of the spinels in mafic rocks at very low Cr2O3 contents (<5 wt%). The fractionation path all along and the reaction with interstitial liquid are accompanied by increasing Fe2O3 contents in the spinel. This likely is caused by a significant increase in the oxygen fugacity, which suggests closed system fractionation processes. Spinel with Cr2O3 < 27 wt% is exsolved into a Fe2O3-rich and an Al2O3-rich phase forming a variety of textures. Remarkably, exsolved spinel in different lithologies from complexes 200 km apart follows one distinct solvus line defining a temperature of ca. 600°C. This indicates that the parental magmas were emplaced and eventually cooled at similar levels in the lithosphere, likely near the crust-mantle boundary. Eventually, these 600°C hot bodies were rapidly transported into colder regions of the upper crust during a regional tectonic

  2. Biogas crops grown in energy crop rotations: Linking chemical composition and methane production characteristics.

    Science.gov (United States)

    Herrmann, Christiane; Idler, Christine; Heiermann, Monika

    2016-04-01

    Methane production characteristics and chemical composition of 405 silages from 43 different crop species were examined using uniform laboratory methods, with the aim to characterise a wide range of crop feedstocks from energy crop rotations and to identify main parameters that influence biomass quality for biogas production. Methane formation was analysed from chopped and over 90 days ensiled crop biomass in batch anaerobic digestion tests without further pre-treatment. Lignin content of crop biomass was found to be the most significant explanatory variable for specific methane yields while the methane content and methane production rates were mainly affected by the content of nitrogen-free extracts and neutral detergent fibre, respectively. The accumulation of butyric acid and alcohols during the ensiling process had significant impact on specific methane yields and methane contents of crop silages. It is proposed that products of silage fermentation should be considered when evaluating crop silages for biogas production. PMID:26836846

  3. OPTIMISATION OF SOLID-STATE AND SOLUTION-BASED SERS SYSTEMS FOR USE IN THE DETECTION OF ANALYTES OF CHEMICAL AND BIOLOGICAL SIGNIFICANCE

    OpenAIRE

    Samuel Bernard Mabbott

    2012-01-01

    AbstractThe University of ManchesterSamuel Bernard MabbottDoctor of PhilosophyOptimisation of Solid-State and Solution-Based SERS Systems for use in the Detection of Analytes of Chemical and Biological Significance13th September 2012Surface enhanced Raman scattering (SERS) has achieved much attention since its conception in 1974. The analytical technique overcomes many difficulties associated with conventional Raman whilst also increasing sensitivity. However, the increased interest and work ...

  4. Significance of Dynamic and Transient Analysis in the Design and Operation of Hybrid Energy Systems

    International Nuclear Information System (INIS)

    Energy systems were historically designed and operated with a specific energy conversion objective, while managing loads and resources. In the recent years, the increased utilization of non-dispatchable renewable sources such as wind and solar has played a role in power quality and the reliability of power systems. In order to mitigate the risk associated with the non-dispatchable resources an integrated approach, such as Hybrid Energy Systems (HES), has to be taken, integrating the loads and resource management between the traditional thermal power plants and the non-dispatchable resources. As our electric energy becomes more diverse in its generation resources, the HES with its operational control system, its real-time view and its dynamic decisions making will become an essential part of the integrated energy systems and improve the overall grid reliability. The operational constraints of the energy sources on both the thermal power plants and the non-dispatchable resources in HES, plays a vital role in the planning and design stage. It is an established fact that the choice of energy source depends on the available natural resources and possible infrastructure. A critical component of decision-making depends on the complementary nature and controllability of the energy sources to supply the load demands with high reliability. Controllability of complex HES to achieve desired performance and flexibility is implemented via coordinated control systems while simultaneously generating electricity and other useful products such as useful heat or hydrogen. These systems are based on instrumentation, signal processing, control theory, and engineering system design. The entire HES along with the control systems are characterized by widely varying time constants. Hence, for a well-coordinated control and operation, we propose physics based modeling of the subsystems to assist in a dynamic and transient analysis. Dynamic and transient analysis in real and non-real time

  5. Significance of Dynamic and Transient Analysis in the Design and Operation of Hybrid Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Panwar, Mayank; Mohanpurkar, Manish; Hovsapian, Rob; Osorio, Julian D.

    2015-02-01

    Energy systems were historically designed and operated with a specific energy conversion objective, while managing loads and resources. In the recent years, the increased utilization of non-dispatchable renewable sources such as wind and solar has played a role in power quality and the reliability of power systems. In order to mitigate the risk associated with the non-dispatchable resources an integrated approach, such as Hybrid Energy Systems (HES), has to be taken, integrating the loads and resource management between the traditional thermal power plants and the non-dispatchable resources. As our electric energy becomes more diverse in its generation resources, the HES with its operational control system, its real-time view and its dynamic decisions making will become an essential part of the integrated energy systems and improve the overall grid reliability. The operational constraints of the energy sources on both the thermal power plants and the non-dispatchable resources in HES, plays a vital role in the planning and design stage. It is an established fact that the choice of energy source depends on the available natural resources and possible infrastructure. A critical component of decision-making depends on the complementary nature and controllability of the energy sources to supply the load demands with high reliability. Controllability of complex HES to achieve desired performance and flexibility is implemented via coordinated control systems while simultaneously generating electricity and other useful products such as useful heat or hydrogen. These systems are based on instrumentation, signal processing, control theory, and engineering system design. The entire HES along with the control systems are characterized by widely varying time constants. Hence, for a well-coordinated control and operation, we propose physics based modeling of the subsystems to assist in a dynamic and transient analysis. Dynamic and transient analysis in real and non-real time

  6. Turkey's major lignite fields and significance of lignite for energy necessity

    Energy Technology Data Exchange (ETDEWEB)

    Balat, M. [Sila Science, Trabzon (Turkey)

    2008-07-01

    The objective of this study is to determine the lignite use for Turkey's energy necessity. Lignite is the most important energy resource of Turkey when compared with others according to the amount of reserves. Lignite is the dominant source of energy produced (43%) in Turkey. Lignite deposits are encountered in almost every region of Turkey. Total lignite reserves are estimated at 8,375 million tons, of which 7,340 million tons (88%) is economically feasible. Share of lignite reserves of Turkey are 2% in the world. Lignite deposits are encountered in almost every region of Turkey. Afsin-Elbistan, Mugla, Soma, Tuncbilek, Seyitomer, Beypazari and Sivas basins constitutes the most important known lignite reserves. The biggest lignite deposits, 40% of the total, are in Afsin-Elbistan. Lignite extraction is expected to increase as the government feels pressure to close down unprofitable hard coal mines that are geologically difficult, increasing the cost of extraction.

  7. Solar energy combined with chemical reactive systems for the production and storage of sustainable energy. A review of thermodynamic principles

    International Nuclear Information System (INIS)

    Highlights: ► Solar radiation power. ► Chemical reactions for the production and storage of usable energy. ► Thermodynamics of solar power. ► Homogeneous and heterogeneous reactive systems. - Abstract: This review article deals with thermodynamics and thermochemistry of processes combining solar radiation power with chemical reactions for the production and storage of usable energy. Some of the most promising procedures of such processes discussed in the literature have been selected as representative examples and are analyzed on the basis of their thermodynamic principles rather than reporting on technical details and feasibility studies with respect to economic potentials. The examples studied involve pure gaseous as well as heterogeneous reactive systems where the shift of chemical equilibria at different temperatures is used to gain chemical energy. The majority of examples focusses on different multistep chemical processes for water splitting into H2 and O2 which have already been tested on laboratory and semi technical scale.

  8. Computed Potential Energy Surfaces and Minimum Energy Pathways for Chemical Reactions

    Science.gov (United States)

    Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

    1994-01-01

    Computed potential energy surfaces are often required for computation of such parameters as rate constants as a function of temperature, product branching ratios, and other detailed properties. For some dynamics methods, global potential energy surfaces are required. In this case, it is necessary to obtain the energy at a complete sampling of all the possible arrangements of the nuclei, which are energetically accessible, and then a fitting function must be obtained to interpolate between the computed points. In other cases, characterization of the stationary points and the reaction pathway connecting them is sufficient. These properties may be readily obtained using analytical derivative methods. We have found that computation of the stationary points/reaction pathways using CASSCF/derivative methods, followed by use of the internally contracted CI method to obtain accurate energetics, gives usefull results for a number of chemically important systems. The talk will focus on a number of applications including global potential energy surfaces, H + O2, H + N2, O(3p) + H2, and reaction pathways for complex reactions, including reactions leading to NO and soot formation in hydrocarbon combustion.

  9. Significant Dissipation of Tidal Energy in the Deep Ocean Inferred from Satellite Altimeter Data

    Science.gov (United States)

    Egbert, G. D.; Ray, R. D.

    2000-01-01

    How and where the ocean tides dissipate their energy are longstanding questions that have consequences ranging from the history of the Moon to the mixing of the oceans. Historically, the principal sink of tidal energy has been thought to be bottom friction in shallow seas. There has long been suggestive however, that tidal dissipation also occurs in the open ocean through the scattering by ocean-bottom topography of surface tides into internal waves, but estimates of the magnitude of this possible sink have varied widely. Here we use satellite altimeter data from Topex/Poseidon to map empirically the tidal energy dissipation. We show that approximately 10(exp 12) watts-that is, 1 TW, representing 25-30% of the total dissipation-occurs in the deep ocean, generally near areas of rough topography. Of the estimated 2 TW of mixing energy required to maintain the large-scale thermohaline circulation of the ocean, one-half could therefore be provided by the tides, with the other half coming from action on the surface of the ocean.

  10. Energy audits reveal significant energy savings potential in India`s commercial air-conditioned building sector

    Energy Technology Data Exchange (ETDEWEB)

    Singh, G.; Presny, D.; Fafard, C. [Resource Management Associates of Madison, Inc., WI (United States)

    1997-12-31

    The United States Agency for International Development (USAID) began its Energy Management Consultation and Training (EMCAT) project in India. The EMCAT project began in 1991 as a six-year (1991--1997) project to improve India`s technological and management capabilities for both the supply of energy and its efficient end use. The end-use component of EMCAT aims for efficient energy utilization by industries and other sectors such as the commercial sector. A specific task under the end-use component was to conduct energy surveys/audits in high energy-use sectors, such as air-conditioned (AC) buildings in the commercial sector, and to identify investment opportunities that could improve energy utilization. This article presents results of pre-investment surveys that were conducted at four commercial air-conditioned facilities in 1995. The four facilities included two luxury hotels in New Delhi, and one luxury hotel and a private hospital in Bombay. Energy conservation opportunities (ECOs) were explored in three major energy-using systems in these buildings: air-conditioning, lighting, and steam and domestic hot water systems.

  11. Nuclear and energies. Synthesis of significant events from June 2013 to December 2013

    International Nuclear Information System (INIS)

    The first two articles concern the energy sector, generally speaking. Among them, the first one addresses the issue of energy transition (perspectives in France, situation in Germany where transition appears to be expensive and polluting with some perverse effects, a world shock wave created by shale gases, proposition by EDF to extend power station life duration from 40 to 50 years, EDF's commitment in nuclear revival in the UK and withdrawal from the USA, new strategy for GDF-Suez) and the second one current events in the renewable energy sector (in China, Germany, UK and Canada, French policy, wind energy bids in France). A second set of articles addresses the nuclear sector: recent evolutions of the uranium industry (mining activities and locations), the back end of the fuel cycle and the dismantling (activities of AREVA, public debate on Cigeo and building permit for ICEDA in France, activities and measures in Germany, in England, in the USA, and in Japan, study performed by the Nuclear Energy Agency on the economic aspect of the back end of the nuclear fuel cycle), the situation of nuclear reactors (perspectives in the world for 2050, perspectives, activities and important events in France, Belgium, Netherlands, United Kingdom, Finland, including the EPR, Turkey, Poland, Czech Republic, Belarus, Russia, China, South Korea, India, Pakistan, Japan, USA and Brazil), the deconstruction of nuclear power plants (legal framework in France, wastes as a major issue for dismantling, industrial challenges of dismantling). The last set of articles concern social and societal aspects of the nuclear sector: recent events in France (for AREVA regarding staff and investments, anti-nuclear activities and momentum), the Cigeo project of geological disposal of high-activity nuclear wastes, hostages in Niger, and diplomatic advances about the Iranian nuclear programme issue

  12. CHEMICALS

    CERN Multimedia

    Medical Service

    2002-01-01

    It is reminded that all persons who use chemicals must inform CERN's Chemistry Service (TIS-GS-GC) and the CERN Medical Service (TIS-ME). Information concerning their toxicity or other hazards as well as the necessary individual and collective protection measures will be provided by these two services. Users must be in possession of a material safety data sheet (MSDS) for each chemical used. These can be obtained by one of several means : the manufacturer of the chemical (legally obliged to supply an MSDS for each chemical delivered) ; CERN's Chemistry Service of the General Safety Group of TIS ; for chemicals and gases available in the CERN Stores the MSDS has been made available via EDH either in pdf format or else via a link to the supplier's web site. Training courses in chemical safety are available for registration via HR-TD. CERN Medical Service : TIS-ME :73186 or service.medical@cern.ch Chemistry Service : TIS-GS-GC : 78546

  13. Measures and potentials of energy-saving in a Chinese fine chemical industrial park

    International Nuclear Information System (INIS)

    This study aims to fill the gap in the literature on energy efficiency and economic analysis of energy-saving measures at the industrial park level by conducting a case study of a typical fine chemical industrial park in China. Based on a five-year intensive data collection, the authors quantitatively examined the energy consumption and energy efficiency of the industrial park in question and evaluated the energy-saving potentials and cost-effectiveness of ten types of energy-saving measures by means of a bottom-up method and scenario analysis. It was found that the energy efficiencies of its two combined heat and power plants in 2007 were 81.5% and 56% respectively. Energy efficiency of the fine chemical industrial park was around 4625.7 GJ per million USD of gross industrial output value, which was only between 20% and 25% of that of the sector of manufacturing raw chemical materials and chemical products in China. The energy-saving potentials of the ten measures amount to about 11% of energy consumption of the industrial park in 2007. A total capital investment of approximately 35 million USD would be needed to realise the potentials. The technical measures explored in the study are generally replicable in other Chinese fine chemical industrial parks. -- Highlights: ► We studied energy-saving potentials and cost on a fine chemical industrial park scale. ► Energy efficiency is 4625.7 GJ/million USD and 97 GJ per tonne-total-organic-carbon-output. ► Bottom-up method and scenario analysis are used to value ten measures' cost-effect. ► Ten measures have 11% energy-saving potential based on energy consumption in 2007. ► Total invest about 35 million USD is needed to realize the potential.

  14. Book of abstracts Chemical Engineering: IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists. Chemical engineering of nanomaterials. Energy- and resource-saving chemical-engineering processes and problems of their intensification. Processes and apparatuses of chemical engineering, chemical cybernetics. Ecological problems of chemical engineering and related fields

    International Nuclear Information System (INIS)

    In the given volume of abstracts of the IV All-Russian Conference on chemical engineering, All-Russian Youth Conference on chemical engineering, All-Russian school on chemical engineering for young scientists and specialists (Moscow, March 18-23, 2012) there are the abstracts of the reports concerning chemical engineering of nanomaterials, energy- and resource-saving chemical-engineering processes, processes and apparatuses of chemical engineering, chemical cybernetics, ecological problems of chemical engineering and related fields. The abstracts deal with state-of-the-art and future development of theoretical and experimental investigations as well as with experience in practical realization of development works in the field of chemical engineering and relative areas

  15. Potential of Coproduction of Energy, Fuels and Chemicals from Biobased Renewable Resources. Transition Path 3. Co-production of Energy, Fuels and Chemicals

    International Nuclear Information System (INIS)

    This report shows how in 2030, biobased alternatives can potentially cover up to 30% of the Netherlands' domestic energy and chemicals demand, effectively reducing CO2 emissions. Maximizing the economical potential of biobased alternatives seems the most attractive strategy. The method to compare various routes has been highly simplified and the conclusions of this report are only valid within the limitations of the underlying assumptions. Nevertheless, the Working group WISE BIOMAS of the Platform Biobased Raw Materials feels that the conclusions are valuable for Dutch policy makers and others interested in the use of biobased raw materials. In 2030, biobased alternatives are expected to be sufficiently competitive to fossil-based alternatives, even without subsidies. They are expected to play a significant role in an energy mix comprised of other renewables as well as 'clean' fossil energy sources. Presently, however, the Netherlands needs to step up its stimulation of biobased applications, through substantial investments in R and D programmes, demonstration plants, as well as measures to stimulate implementation. The whole package of tax reductions, local government purchases, etc., as well as direct financial support should amount to approximately 500 million euros per year. The simplified study presented here provides input for more realistic macro-economic scenario analysis taking actual and updated cost-availability relations including second generation biofuels and biochemicals, land use, international trade, etc., into account. Initial discussions with for instance the Netherlands Bureau for Economic Policy Analysis (Centraal Plan Bureau or CPB) have taken place, but are not covered in this report. It is urgently suggested to update macro-economic scenarios for securing the best Netherlands' position among the accelerating global development towards biobased resources

  16. Powering the planet: Chemical challenges in solar energy utilization

    OpenAIRE

    Lewis, Nathan S.; Nocera, Daniel G.

    2006-01-01

    Global energy consumption is projected to increase, even in the face of substantial declines in energy intensity, at least 2-fold by midcentury relative to the present because of population and economic growth. This demand could be met, in principle, from fossil energy resources, particularly coal. However, the cumulative nature of CO2 emissions in the atmosphere demands that holding atmospheric CO2 levels to even twice their preanthropogenic values by midcentury will require invention, devel...

  17. The limits of local correlation theory: electronic delocalization and chemically smooth potential energy surfaces.

    Science.gov (United States)

    Subotnik, Joseph E; Sodt, Alex; Head-Gordon, Martin

    2008-01-21

    Local coupled-cluster theory provides an algorithm for measuring electronic correlation quickly, using only the spatial locality of localized electronic orbitals. Previously, we showed [J. Subotnik et al., J. Chem. Phys. 125, 074116 (2006)] that one may construct a local coupled-cluster singles-doubles theory which (i) yields smooth potential energy surfaces and (ii) achieves near linear scaling. That theory selected which orbitals to correlate based only on the distances between the centers of different, localized orbitals, and the approximate potential energy surfaces were characterized as smooth using only visual identification. This paper now extends our previous algorithm in three important ways. First, locality is now based on both the distances between the centers of orbitals as well as the spatial extent of the orbitals. We find that, by accounting for the spatial extent of a delocalized orbital, one can account for electronic correlation in systems with some electronic delocalization using fast correlation methods designed around orbital locality. Second, we now enforce locality on not just the amplitudes (which measure the exact electron-electron correlation), but also on the two-electron integrals themselves (which measure the bare electron-electron interaction). Our conclusion is that we can bump integrals as well as amplitudes, thereby gaining a tremendous increase in speed and paradoxically increasing the accuracy of our LCCSD approach. Third and finally, we now make a rigorous definition of chemical smoothness as requiring that potential energy surfaces not support artificial maxima, minima, or inflection points. By looking at first and second derivatives from finite difference techniques, we demonstrate complete chemical smoothness of our potential energy surfaces (bumping both amplitudes and integrals). These results are significant both from a theoretical and from a computationally practical point of view. PMID:18205484

  18. Agrice 1994-2000 - Activity report. Agriculture for chemicals and energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-07-01

    The emergence of new energy, chemicals and materials markets for agricultural products calls for an ongoing commitment to significant and stable funding for research. Even more importantly, these new markets also necessitate better coordination between the actors across the field, ranging from multidisciplinary research teams and agro-industrial companies to users in the petrochemicals, chemicals and materials sectors, and agricultural production. The need for this coordination is even greater today, in light of the key role that 'non-food' supply chains play in environmental protection: efforts to mitigate the greenhouse effect, reduction of VOC emissions, product safety and biodegradability, rational farming practices, etc. With these ends in mind the scientific interest group AGRICE- Agriculture for Chemicals and Energy- was created in France in 1994 by government bodies and eight partners. Today AGRICE includes the following members: the Institut Francais du Petrole (IFP), the Institut National de Recherche Agronomique (INRA), the Centre National de Recherche Scientifique (CNRS) and the Agence de l'Environnement et de la Maitrise de l'Energie (ADEME), professional organisations in oilseeds (ONIDOL), grains (AGPB) and beets (CGB), AVENTIS, TOTAL FINA ELF, LIMAGRAIN and EDF, the French ministries of Agriculture, Industry, Research, and Environment. AGRICE was founded for a six-year renewable term, and its management entrusted to ADEME. The group has worked to develop significant collaborative efforts across Europe, notably through the European Renewable Resources and Materials Association (ERRMA). AGRICE is due to be renewed with a broader base of partners in 2001. This report presents: 1 - the AGRICE profile, scope of activity (Biofuels vehicles (Ester/Oils, Ethanol/Ether) and non-vehicles (Energy crops, Processes), Biomolecules (Lubricants, Surfactants, Solvents, Other biomolecules), Biomaterials (Biopolymers, Agro-materials)), Financial

  19. On the Use of Energy Storage Technologies for Regulation Services in Electric Power Systems with Significant Penetration of Wind Energy

    DEFF Research Database (Denmark)

    Yang, Bo; Makarov, Yuri; Desteese, John;

    2008-01-01

    Energy produced by intermittent renewable resources is sharply increasing in the United States. At high penetration levels, volatility of wind power production could cause additional problems for the power system balancing functions such as regulation. This paper reports some partial results of a...... for the BPA and California ISO systems by using a large energy storage facility. The paper evaluates several utility-scale energy storage technology options for their usage as regulation resources. The regulation service requires a participating resource to quickly vary its power output following the...... project work, recently conducted by the Pacific Northwest National Laboratory (PNNL) for Bonneville Power Administration (BPA). The project proposes to mitigate additional intermittency with the help of Wide Area Energy Management System (WAEMS) that would provide a two-way simultaneous regulation service...

  20. Constraints on the source of ultra-high energy cosmic rays using anisotropy vs chemical composition

    CERN Document Server

    Liu, Ruo-Yu; Lemoine, Martin; Wang, Xiang-Yu; Waxman, Eli

    2013-01-01

    The joint analysis of anisotropy signals and chemical composition of ultra-high energy cosmic rays offers strong potential for shedding light on the sources of these particles. Following up on an earlier idea, this paper studies the anisotropies produced by protons of energy >E/Z, assuming that anisotropies at energy >E have been produced by nuclei of charge Z, which share the same magnetic rigidity. We calculate the number of secondary protons produced through photodisintegration of the primary heavy nuclei. Making the extreme assumption that the source does not inject any proton, we find that the source(s) responsible for anisotropies such as reported by the Pierre Auger Observatory should lie closer than ~20-30, 80-100 and 180-200 Mpc if the anisotropy signal is mainly composed of oxygen, silicon and iron nuclei respectively. A violation of this constraint would otherwise result in the secondary protons forming a more significant anisotropy signal at lower energies. Even if the source were located closer t...

  1. Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: October-December 1997

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1999-02-01

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period October--December 1997. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within six major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information. Activities conducted within the area of Hot Cell Operations included efforts to optimize the processing conditions for Enhanced Sludge Washing of Hanford tank sludge, the testing of candidate absorbers and ion exchangers under continuous-flow conditions using actual supernatant from the Melton Valley Storage Tanks, and attempts to develop a cesium-specific spherical inorganic sorbent for the treatment of acidic high-salt waste solutions. Within the area of Process Chemistry and Thermodynamics, the problem of solids formation in process solutions from caustic treatment of Hanford sludge was addressed and experimental collaborative efforts with Russian scientists to determine the solidification conditions of yttrium barium, and copper oxides from their melts were completed.

  2. Structure, topology and chemical order in Ge-As-Te glasses: a high-energy x-ray diffraction study

    International Nuclear Information System (INIS)

    High-energy x-ray diffraction is employed to study the atomic structure of bulk GexAs2xTe100-3x glasses with compositions in the range 25 ≤ 3x ≤ 70. The coordination environments of Te atoms suggest significant violation of chemical order in these glasses. Analyses of the nearest-neighbor coordination environments and the parameters for the first sharp diffraction peak indicate that these telluride glasses are structurally and chemically more disordered as compared with their sulfide or selenide analogs. The compositional evolution of the structural parameters is shown to be consistent with the corresponding variation in molar volume and glass transition temperature.

  3. Quantum chemical approach for condensed-phase thermochemistry (III): Accurate evaluation of proton hydration energy and standard hydrogen electrode potential

    Science.gov (United States)

    Ishikawa, Atsushi; Nakai, Hiromi

    2016-04-01

    Gibbs free energy of hydration of a proton and standard hydrogen electrode potential were evaluated using high-level quantum chemical calculations. The solvent effect was included using the cluster-continuum model, which treated short-range effects by quantum chemical calculations of proton-water complexes, and the long-range effects by a conductor-like polarizable continuum model. The harmonic solvation model (HSM) was employed to estimate enthalpy and entropy contributions due to nuclear motions of the clusters by including the cavity-cluster interactions. Compared to the commonly used ideal gas model, HSM treatment significantly improved the contribution of entropy, showing a systematic convergence toward the experimental data.

  4. Bioelectrochemical Integration of Waste Heat Recovery, Waste-to- Energy Conversion, and Waste-to-Chemical Conversion with Industrial Gas and Chemical Manufacturing Processes

    Energy Technology Data Exchange (ETDEWEB)

    Mac Dougall, James [Air Products and Chemicals, Inc., Allentown, PA (United States)

    2016-02-05

    Many U.S. manufacturing facilities generate unrecovered, low-grade waste heat, and also generate or are located near organic-content waste effluents. Bioelectrochemical systems, such as microbial fuel cells and microbial electrolysis cells, provide a means to convert organic-content effluents into electric power and useful chemical products. A novel biochemical electrical system for industrial manufacturing processes uniquely integrates both waste heat recovery and waste effluent conversion, thereby significantly reducing manufacturing energy requirements. This project will enable the further development of this technology so that it can be applied across a wide variety of US manufacturing segments, including the chemical, food, pharmaceutical, refinery, and pulp and paper industries. It is conservatively estimated that adoption of this technology could provide nearly 40 TBtu/yr of energy, or more than 1% of the U.S. total industrial electricity use, while reducing CO2 emissions by more than 6 million tons per year. Commercialization of this technology will make a significant contribution to DOE’s Industrial Technology Program goals for doubling energy efficiency and providing a more robust and competitive domestic manufacturing base.

  5. Minimizing the Free Energy: A Computer Method for Teaching Chemical Equilibrium Concepts.

    Science.gov (United States)

    Heald, Emerson F.

    1978-01-01

    Presents a computer method for teaching chemical equilibrium concepts using material balance conditions and the minimization of the free energy. Method for the calculation of chemical equilibrium, the computer program used to solve equilibrium problems and applications of the method are also included. (HM)

  6. Qingtongxia Aluminum Carrying Out Off-site Renovation in Ningdong Energy & Chemical Base

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Recently,the off-site renovation project of Qingtongxia Aluminum commenced the con- struction in Linhe General Industrial Park of Ningdong Energy & Chemical Base,symboliz- ing a concrete step of Qingtongxia Aluminum

  7. On the Use of Energy Storage Technologies for Regulation Services in Electric Power Systems with Significant Penetration of Wind Energy

    DEFF Research Database (Denmark)

    Yang, Bo; Makarov, Yuri; Desteese, John; Viswanathan, Vilayanur; Nyeng, Preben; McManus, Bart; Pease, John

    2008-01-01

    rapidly and frequently changing regulation signal. Several energy storage options have been analyzed based on thirteen selection criteria. The evaluation process resulted in the selection of flywheels, pumped hydro electric power (or conventional hydro electric power) plant and sodium sulfur or nickel......Energy produced by intermittent renewable resources is sharply increasing in the United States. At high penetration levels, volatility of wind power production could cause additional problems for the power system balancing functions such as regulation. This paper reports some partial results of a...... project work, recently conducted by the Pacific Northwest National Laboratory (PNNL) for Bonneville Power Administration (BPA). The project proposes to mitigate additional intermittency with the help of Wide Area Energy Management System (WAEMS) that would provide a two-way simultaneous regulation service...

  8. Targeted energy transfer between a Rotor and a Morse oscillator: A model for selective chemical dissociation

    OpenAIRE

    Memboeuf, Antony; Aubry, Serge

    2005-01-01

    Standard Kramers theory of chemical reactions involves a coupling with a Langevin thermal bath which intrinsically forbids the possible existence of Discrete Breathers (DBs) (i.e. local modes). However, it is now known that in complex systems, that energy may focus for long time as Discrete Breathers (local mode). In very special systems, targeted energy transfer may occur subsequently to another selected site and induces an ultraselective chemical reaction operating at low temperature. The d...

  9. The chemical digestion of Ti6Al7Nb scaffolds produced by Selective Laser Melting reduces significantly ability of Pseudomonas aeruginosa to form biofilm.

    Science.gov (United States)

    Junka, Adam F; Szymczyk, Patrycja; Secewicz, Anna; Pawlak, Andrzej; Smutnicka, Danuta; Ziółkowski, Grzegorz; Bartoszewicz, Marzenna; Chlebus, Edward

    2016-01-01

    In our previous work we reported the impact of hydrofluoric and nitric acid used for chemical polishing of Ti-6Al-7Nb scaffolds on decrease of the number of Staphylococcus aureus biofilm forming cells. Herein, we tested impact of the aforementioned substances on biofilm of Gram-negative microorganism, Pseudomonas aeruginosa, dangerous pathogen responsible for plethora of implant-related infections. The Ti-6Al-7Nb scaffolds were manufactured using Selective Laser Melting method. Scaffolds were subjected to chemical polishing using a mixture of nitric acid and fluoride or left intact (control group). Pseudomonal biofilm was allowed to form on scaffolds for 24 hours and was removed by mechanical vortex shaking. The number of pseudomonal cells was estimated by means of quantitative culture and Scanning Electron Microscopy. The presence of nitric acid and fluoride on scaffold surfaces was assessed by means of IR and rentgen spetorscopy. Quantitative data were analysed using the Mann-Whitney test (P ≤ 0.05). Our results indicate that application of chemical polishing correlates with significant drop of biofilm-forming pseudomonal cells on the manufactured Ti-6Al-7Nb scaffolds ( p = 0.0133, Mann-Whitney test) compared to the number of biofilm-forming cells on non-polished scaffolds. As X-ray photoelectron spectroscopy revealed the presence of fluoride and nitrogen on the surface of scaffold, we speculate that drop of biofilm forming cells may be caused by biofilm-supressing activity of these two elements. PMID:27150429

  10. Chemical energy in an introductory physics course for the life sciences

    CERN Document Server

    Dreyfus, Benjamin W; Geller, Benjamin D; Sawtelle, Vashti; Turpen, Chandra; Redish, Edward F

    2013-01-01

    Energy is a complex idea that cuts across scientific disciplines. For life science students, an approach to energy that incorporates chemical bonds and chemical reactions is better equipped to meet the needs of life sciences students than a traditional introductory physics approach that focuses primarily on mechanical energy. We present a curricular sequence, or thread, designed to build up students' understanding of chemical energy in an introductory physics course for the life sciences. This thread is designed to connect ideas about energy from physics, biology, and chemistry. We describe the kinds of connections among energetic concepts that we intended to develop to build interdisciplinary coherence, and present some examples of curriculum materials and student data that illustrate our approach.

  11. Chemical energy storage system for Solar Electric Generating System (SEGS) solar thermal power plant

    International Nuclear Information System (INIS)

    This paper reports the Pacific Northwest Laboratory evaluated the potential feasibility of using chemical energy storage at the Solar Electric Generating System (SEGS) power plants developed by Luz International. Like sensible or latent heat energy storage systems, chemical energy storage can be beneficially applied to solar thermal power plants to dampen the impact of cloud transients, extend the daily operating period, and/or allow a higher fraction of power production to occur during high-valued peak demand periods. Higher energy storage densities make chemical energy storage a potentially attractive option. The results of the evaluation indicated that a system based on the reversible reaction, CaO + H2O = Ca(OH)2, could be technically and economically feasible for this application, but many technical and economic issues must be resolved

  12. Chemical latent heat for transport of nuclear energy over long distances

    International Nuclear Information System (INIS)

    The oil crisis has made clear the necessity to use nuclear energy to an increasing extent for purposes of energy supply and, particularly, for the supply of non-electric energy market. This purpose is served by the energy supply system 'Nuclear Energy over Long Distances', by which nuclear energy is transported in a converted form and transformed into the applicable forms of energy such as hot water or water vapour and electricity. The energy transport involves the transport of the 'latent heat gas', which by chemical reactions will be absorbing or emitting thermal energy. The latent heat gas 'sythesis gas/methane' presents several substantial advantages. The nuclear heat source of the energy supply system 'Nuclear Energy over Long Distances' is the high-temperature reactor. (author)

  13. Capacitive technology for energy extraction from chemical potential differences

    NARCIS (Netherlands)

    Bastos Sales, B.

    2013-01-01

    This thesis introduces the principle of Capacitive energy extraction based on Donnan Potential (CDP) to exploit salinity gradients. It also shows the fundamental characterization and improvements of CDP. An alternative application of this technology aimed at thermal gradients was tested.  

  14. CO2 recycling: a key strategy to introduce green energy in the chemical production chain.

    Science.gov (United States)

    Perathoner, Siglinda; Centi, Gabriele

    2014-05-01

    The introduction of renewable energy in the chemical production chain is a key strategic factor both to realize a sustainable, resource-efficient, low-carbon economy and society and to drive innovation and competiveness in the chemical production. This Concept discusses this concept in terms of motivations, perspectives, and impact as well as technical barriers to achieve this goal. It is shown how an important element to realize this scenario is to foster the paths converting carbon dioxide (CO2) into feedstock for the chemical/process industry, which is one of the most efficient methods to rapidly introduce renewable energy into the chemical production chain. Some of the possible options to proceed in this direction are discussed, with focus on the technical barriers and enabling factors such as catalysis. The tight interconnection between CO2 management and the use of renewable energy is evidenced. PMID:24599714

  15. Valorization of rendering industry wastes and co-products for industrial chemicals, materials and energy: review.

    Science.gov (United States)

    Mekonnen, Tizazu; Mussone, Paolo; Bressler, David

    2016-01-01

    Over the past decades, strong global demand for industrial chemicals, raw materials and energy has been driven by rapid industrialization and population growth across the world. In this context, long-term environmental sustainability demands the development of sustainable strategies of resource utilization. The agricultural sector is a major source of underutilized or low-value streams that accompany the production of food and other biomass commodities. Animal agriculture in particular constitutes a substantial portion of the overall agricultural sector, with wastes being generated along the supply chain of slaughtering, handling, catering and rendering. The recent emergence of bovine spongiform encephalopathy (BSE) resulted in the elimination of most of the traditional uses of rendered animal meals such as blood meal, meat and bone meal (MBM) as animal feed with significant economic losses for the entire sector. The focus of this review is on the valorization progress achieved on converting protein feedstock into bio-based plastics, flocculants, surfactants and adhesives. The utilization of other rendering streams such as fat and ash rich biomass for the production of renewable fuels, solvents, drop-in chemicals, minerals and fertilizers is also critically reviewed. PMID:25163531

  16. Energetic and chemical use of waste material and renewable energies

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.; Houmoeller, A.P. [ELSAM, Fredericia (Denmark)

    1996-12-31

    The paper will begin with a summary of the Danish energy policies from the mid-1970s and until today when the focus is on national self-sufficiency and combined heat and power - including industrial combined heat and power and renewable energies with emphasis on wind turbines and biofuels. The planning conditions of the Danish electricity utilities will be discussed, i.e. 20 per cent CO{sub 2} reduction by 2005, continuous reduction of SO{sub 2} and NO{sub x}, and finally the conversion of 5 per cent of the fuel from coal to straw and wood chips. Afterwards, the status of biofuels in Denmark will be described with emphasis on resources and prices. The main biofuel in Denmark is surplus production from agriculture - straw or other biofuels with straw-like properties. (orig./GL)

  17. Biomass as a Sustainable Energy Source: An Illustration of Chemical Engineering Thermodynamic Concepts

    Science.gov (United States)

    Mohan, Marguerite A.; May, Nicole; Assaf-Anid, Nada M.; Castaldi, Marco J.

    2006-01-01

    The ever-increasing global demand for energy has sparked renewed interest within the engineering community in the study of sustainable alternative energy sources. This paper discusses a power generation system which uses biomass as "fuel" to illustrate the concepts taught to students taking a graduate level chemical engineering process…

  18. Production of high-energy chemicals using solar energy heat. Project 8999, final report for the period September 1, 1977--May 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Dafler, J.R.; Sinnott, J.; Novil, M.; Yudow, B.D.; Rackoff, M.G.

    1978-12-01

    The first phase of a study to identify candidate processes and products suitable for future exploitation using high-temperature solar energy is presented. This phase has been principally analytical, consisting of techno-economic studies, thermodynamic assessments of chemical reactions and processes, and the determination of market potentials for major chemical commodities that use significant amounts of fossil resources today. The objective was to identify energy-intensive processes that would be suitable for the production of chemicals and fuels using solar energy process heat. Of particular importance was the comparison of relative costs and energy requirements for the selected solar product versus costs for the product derived from conventional processing. The assessment methodology used a systems analytical approach to identify processes and products having the greatest potential for solar energy-thermal processing. This approach was used to establish the basis for work to be carried out in subsequent phases of development. It has been the intent of the program to divide the analysis and process identification into the following three distinct areas: (1) process selection, (2) process evaluation, and (3) ranking of processes. Four conventional processes were selected for assessment namely, methanol synthesis, styrene monomer production, vinyl chloride monomer production, and terephthalic acid production.

  19. The top 50 commodity chemicals: Impact of catalytic process limitations on energy, environment, and economics

    Energy Technology Data Exchange (ETDEWEB)

    Tonkovich, A.L.Y.; Gerber, M.A.

    1995-08-01

    The production processes for the top 50 U.S. commodity chemicals waste energy, generate unwanted byproducts, and require more than a stoichiometric amount of feedstocks. Pacific Northwest Laboratory has quantified this impact on energy, environment, and economics for the catalytically produced commodity chemicals. An excess of 0.83 quads of energy per year in combined process and feedstock energy is required. The major component, approximately 54%, results from low per-pass yields and the subsequent separation and recycle of unreacted feedstocks. Furthermore, the production processes, either directly or through downstream waste treatment steps, release more than 20 billion pounds of carbon dioxide per year to the environment. The cost of the wasted feedstock exceeds 2 billion dollars per year. Process limitations resulting from unselective catalysis and unfavorable reaction thermodynamic constraints are the major contributors to this waste. Advanced process concepts that address these problems in an integrated manner are needed to improve process efficiency, which would reduce energy and raw material consumption, and the generation of unwanted byproducts. Many commodity chemicals are used to produce large volume polymer products. Of the energy and feedstock wasted during the production of the commodity chemicals, nearly one-third and one-half, respectively, represents chemicals used as polymer precursors. Approximately 38% of the carbon dioxide emissions are generated producing polymer feedstocks.

  20. Optimising energy recovery and use of chemicals, resources and materials in modern waste-to-energy plants

    International Nuclear Information System (INIS)

    Highlights: • WtE plants are to be optimized beyond current acceptance levels. • Emission and consumption data before and after 5 technical improvements are discussed. • Plant performance can be increased without introduction of new techniques or re-design. • Diagnostic skills and a thorough understanding of processes and operation are essential. - Abstract: Due to ongoing developments in the EU waste policy, Waste-to-Energy (WtE) plants are to be optimized beyond current acceptance levels. In this paper, a non-exhaustive overview of advanced technical improvements is presented and illustrated with facts and figures from state-of-the-art combustion plants for municipal solid waste (MSW). Some of the data included originate from regular WtE plant operation – before and after optimisation – as well as from defined plant-scale research. Aspects of energy efficiency and (re-)use of chemicals, resources and materials are discussed and support, in light of best available techniques (BAT), the idea that WtE plant performance still can be improved significantly, without direct need for expensive techniques, tools or re-design. In first instance, diagnostic skills and a thorough understanding of processes and operations allow for reclaiming the silent optimisation potential

  1. Optimising energy recovery and use of chemicals, resources and materials in modern waste-to-energy plants

    Energy Technology Data Exchange (ETDEWEB)

    De Greef, J.; Villani, K.; Goethals, J.; Van Belle, H. [Keppel Seghers, Center of Excellence, Hoofd 1, B-2830 Willebroek (Belgium); Van Caneghem, J., E-mail: jo.vancaneghem@cit.kuleuven.be [University of Leuven, Department of Chemical Engineering, ProcESS (Process Engineering for Sustainable Systems) Division, Willem De Croylaan 46, 3001 Leuven (Belgium); Group T Leuven Engineering College, Association of the University of Leuven, Andreas Vesaliusstraat 13, B-3000 Leuven (Belgium); Vandecasteele, C. [University of Leuven, Department of Chemical Engineering, ProcESS (Process Engineering for Sustainable Systems) Division, Willem De Croylaan 46, 3001 Leuven (Belgium)

    2013-11-15

    Highlights: • WtE plants are to be optimized beyond current acceptance levels. • Emission and consumption data before and after 5 technical improvements are discussed. • Plant performance can be increased without introduction of new techniques or re-design. • Diagnostic skills and a thorough understanding of processes and operation are essential. - Abstract: Due to ongoing developments in the EU waste policy, Waste-to-Energy (WtE) plants are to be optimized beyond current acceptance levels. In this paper, a non-exhaustive overview of advanced technical improvements is presented and illustrated with facts and figures from state-of-the-art combustion plants for municipal solid waste (MSW). Some of the data included originate from regular WtE plant operation – before and after optimisation – as well as from defined plant-scale research. Aspects of energy efficiency and (re-)use of chemicals, resources and materials are discussed and support, in light of best available techniques (BAT), the idea that WtE plant performance still can be improved significantly, without direct need for expensive techniques, tools or re-design. In first instance, diagnostic skills and a thorough understanding of processes and operations allow for reclaiming the silent optimisation potential.

  2. Chemical potential and internal energy of the noninteracting Fermi gas in fractional-dimensional space

    Indian Academy of Sciences (India)

    S Panda; B K Panda

    2010-09-01

    Chemical potential and internal energy of a noninteracting Fermi gas at low temperature are evaluated using the Sommerfeld method in the fractional-dimensional space. When temperature increases, the chemical potential decreases below the Fermi energy for any dimension equal to 2 and above due to the small entropy, while it increases above the Fermi energy for dimensions below 2 as a result of high entropy. The ranges of validity of the truncated series expansions of these quantities are extended from low to intermediate temperature regime as well as from high to relatively low density regime by using the Pad ́e approximant technique.

  3. Biorefineries to integrate fuel, energy and chemical production processes

    Directory of Open Access Journals (Sweden)

    Enrica Bargiacchi

    2007-12-01

    Full Text Available The world of renewable energies is in fast evolution and arouses political and public interests, especially as an opportunity to boost environmental sustainability by mitigation of greenhouse gas emissions. This work aims at examining the possibilities related to the development of biorefineries, where biomass conversion processes to produce biofuels, electricity and biochemicals are integrated. Particular interest is given to the production processes of biodiesel, bioethanol and biogas, for which present world situation, problems, and perspectives are drawn. Potential areas for agronomic and biotech researches are also discussed. Producing biomass for biorefinery processing will eventually lead to maximize yields, in the non food agriculture.

  4. Quarterly Progress Report for the Chemical and Energy Research Section of the Chemical Technology Division: July-September 1999

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    2001-04-16

    This report summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period July-September 1999. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within ten major areas of research: Hot Cell Operations, Process Chemistry, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Physical Properties Research, Biochemical Engineering, Separations and Materials Synthesis, Fluid Structures and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information. Activities conducted within the area of the Cell Operations involved the testing of two continuously stirred tank reactors in series to evaluate the Savannah River-developed process of small-tank tetraphenylborate precipitation to remove cesium, strontium and transuranics from supernatant. Within the area of Process Chemistry, various topics related to solids formation in process solutions from caustic treatment of Hanford sludge were addressed. Saltcake dissolution efforts continued, including the development of a predictive algorithm. New initiatives for the section included modeling activities centered on detection of hydrogen in {sup 233}U storage wells and wax formation in petroleum mixtures, as well as support for the Spallation Neutron Source (investigation of transmutation products formed during operation). Other activities involved in situ grouting and evaluation of options for use (i.e., as castable shapes) of depleted uranium. In a continuation of activities of the preceding

  5. Chemical reactions of ultracold alkali dimers in the lowest-energy $^3\\Sigma$ state

    CERN Document Server

    Tomza, Michał; Moszynski, Robert; Krems, Roman V

    2013-01-01

    We show that the interaction of polar alkali dimers in the quintet spin state leads to the formation of a deeply bound reaction complex. The reaction complex can decompose adiabatically into homonuclear alkali dimers (for all molecules except KRb) and into alkali trimers (for all molecules). We show that there are no barriers for these chemical reactions. This means that all alkali dimers in the $a^3\\Sigma^+$ state are chemically unstable at ultracold temperature, and the use of an optical lattice to segregate the molecules and suppress losses may be necessary. In addition, we calculate the minimum energy path for the chemical reactions of alkali hydrides. We find that the reaction of two molecules is accelerated by a strong attraction between the alkali atoms, leading to a barrierless process that produces hydrogen atoms with large kinetic energy. We discuss the unique features of the chemical reactions of ultracold alkali dimers in the $a^3\\Sigma^+$ electronic state.

  6. Search with the ATLAS detector for new physics with significant missing transverse energy and two isolated leptons

    Indian Academy of Sciences (India)

    João Firmino Da Costa; on behalf of the ATLAS Collaboration

    2012-11-01

    Results of searches for supersymmetry in events with significant missing transverse energy and two isolated leptons with the ATLAS experiment at the LHC are presented. Three analyses are presented here, the first two are analyses with leptons of opposite charge and same charge, respectively. The third one is an analysis that searches for an excess of same-flavour oppositecharge lepton pairs over those of different-flavour. Data corresponding to an integrated luminosity of 1 fb-1 are analysed.

  7. Biotechnology in China II. Chemicals, energy and environment

    Energy Technology Data Exchange (ETDEWEB)

    Tsao, G.T. [Purdue Univ., West Lafayette, IN (United States). Lab. Renewable Resources Engineering; Ouyang, Pingkai [Nanjing Univ. of Technology (China). College of Life Science and Pharmaceutical Engineering; Chen, Jian (eds.) [Jiangnan Univ., Wuxi (China). School of Biotechnology

    2010-07-01

    , biochemists, molecular biologists, bioengineers, chemical engineers, and food and pharmaceutical chemists, environmental engineers working in industry, at universities or at public institutions. The volume editors and the authors of the individual chapters have been chosen for their recognized expertise and their contributions to the various fields of biotechnology. Their willingness to impart this knowledge to their colleagues forms the basis of the book and is gratefully acknowledged. Moreover, this work could not have been brought to fruition without the foresight and the constant and diligent support from the Springer. The seven chapters are organized by more than 20 outstanding biotechnological groups in China. The first chapter reviews the general development history and the perspectives of the industrial biotechnology in China. The next two chapters consider the biotechnological production of organic chemicals and biofuels in China. The fourth chapter summarizes the development of bioreactors and bioseparation. The fifth chapter gives a profile on the current status of environmental biotechnology in China. Special attention is given here to traditional Chinese biotechnology. The last chapter describes the new biotechnology in China. A carefully selected and distinguished Editorial Board stands behind the series. Its members come from key institutions representing scientific input from about 20 countries. We are grateful to Springer for publishing Advances in Biochemical Engineering/Biotechnology with their customary excellence. Special thanks are due to Editorial Board, without whose constant efforts the volumes could not be published. Finally, the editors wish to thank the Chinese researchers working in the field for their diligence, courage and wisdom, which greatly facilitate the development of Chinese biotechnology. We believe that we have tried our best to draw a more comprehensive atlas for the development of biochemical engineering and biotechnology in China

  8. Energy-dependent existence of soliton in the synthesis of chemical elements

    OpenAIRE

    Iwata, Yoritaka

    2014-01-01

    Light chemical elements are, for instance, produced through ion collisions taking place in the core of stars, where fusion is particularly important to the synthesis of chemical elements. Meanwhile soliton provides non-interacting transparency leading to the hindrance of fusion cross section. In order to explain high fusion cross section actually observed in low incident energies, it is necessary to discover the suppression mechanism of soliton propagation. In this paper, based on a systemati...

  9. Purposeful synthesis of chemical elements and ecologically pure mobile sources of energy

    International Nuclear Information System (INIS)

    It is well known [1] that the natural geo-transmutation of chemical elements occurs in the atmosphere and earth in the regions of a strong change in geo-, bio-, acoustic-, and electromagnetic fields. The mineral row materials contain the same accompanying chemical combinations which are independent of mineral deposit [2]. This means that the formation of chemical elements occurs in the same physical and chemical conditions. These conditions were simulated on the fundamental cooperative resonance synchronization principle [1]. The experimental facility was constructed on the basis of our model which provided with the calculated final chemical elements. These experimental results indicate new possibilities for, simulating, inducing and controlling nuclear reactions by low energy external fields. The borrowing from the geo-transmutation mechanisms of chemical elements creates the fundamental directions in low energy nuclear reaction researches for construction of new ecologically pure mobile sources of energy independent of oil, gas and coal, new substances, and technologies. References [1] F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/0610002 2006. [2] V.A. Krivzskii, Transmutazija ximicheskix elementov v evolyuzii Semli (in Russian), Moscow 2003

  10. Chemical control over the energy-level alignment in a two-terminal junction

    Science.gov (United States)

    Yuan, Li; Franco, Carlos; Crivillers, Núria; Mas-Torrent, Marta; Cao, Liang; Sangeeth, C. S. Suchand; Rovira, Concepció; Veciana, Jaume; Nijhuis, Christian A.

    2016-07-01

    The energy-level alignment of molecular transistors can be controlled by external gating to move molecular orbitals with respect to the Fermi levels of the source and drain electrodes. Two-terminal molecular tunnelling junctions, however, lack a gate electrode and suffer from Fermi-level pinning, making it difficult to control the energy-level alignment of the system. Here we report an enhancement of 2 orders of magnitude of the tunnelling current in a two-terminal junction via chemical molecular orbital control, changing chemically the molecular component between a stable radical and its non-radical form without altering the supramolecular structure of the junction. Our findings demonstrate that the energy-level alignment in self-assembled monolayer-based junctions can be regulated by purely chemical modifications, which seems an attractive alternative to control the electrical properties of two-terminal junctions.

  11. Free energy calculations, enhanced by a Gaussian ansatz, for the "chemical work" distribution.

    Science.gov (United States)

    Boulougouris, Georgios C

    2014-05-15

    The evaluation of the free energy is essential in molecular simulation because it is intimately related with the existence of multiphase equilibrium. Recently, it was demonstrated that it is possible to evaluate the Helmholtz free energy using a single statistical ensemble along an entire isotherm by accounting for the "chemical work" of transforming each molecule, from an interacting one, to an ideal gas. In this work, we show that it is possible to perform such a free energy perturbation over a liquid vapor phase transition. Furthermore, we investigate the link between a general free energy perturbation scheme and the novel nonequilibrium theories of Crook's and Jarzinsky. We find that for finite systems away from the thermodynamic limit the second law of thermodynamics will always be an inequality for isothermal free energy perturbations, resulting always to a dissipated work that may tend to zero only in the thermodynamic limit. The work, the heat, and the entropy produced during a thermodynamic free energy perturbation can be viewed in the context of the Crooks and Jarzinsky formalism, revealing that for a given value of the ensemble average of the "irreversible" work, the minimum entropy production corresponded to a Gaussian distribution for the histogram of the work. We propose the evaluation of the free energy difference in any free energy perturbation based scheme on the average irreversible "chemical work" minus the dissipated work that can be calculated from the variance of the distribution of the logarithm of the work histogram, within the Gaussian approximation. As a consequence, using the Gaussian ansatz for the distribution of the "chemical work," accurate estimates for the chemical potential and the free energy of the system can be performed using much shorter simulations and avoiding the necessity of sampling the computational costly tails of the "chemical work." For a more general free energy perturbation scheme that the Gaussian ansatz may not be

  12. An Energy Balance Model to Predict Chemical Partitioning in a Photosynthetic Microbial Mat

    Science.gov (United States)

    Hoehler, Tori M.; Albert, Daniel B.; DesMarais, David J.

    2006-01-01

    Studies of biosignature formation in photosynthetic microbial mat communities offer potentially useful insights with regards to both solar and extrasolar astrobiology. Biosignature formation in such systems results from the chemical transformation of photosynthetically fixed carbon by accessory microorganisms. This fixed carbon represents a source not only of reducing power, but also energy, to these organisms, so that chemical and energy budgets should be coupled. We tested this hypothesis by applying an energy balance model to predict the fate of photosynthetic productivity under dark, anoxic conditions. Fermentation of photosynthetically fixed carbon is taken to be the only source of energy available to cyanobacteria in the absence of light and oxygen, and nitrogen fixation is the principal energy demand. The alternate fate for fixed carbon is to build cyanobacterial biomass with Redfield C:N ratio. The model predicts that, under completely nitrogen-limited conditions, growth is optimized when 78% of fixed carbon stores are directed into fermentative energy generation, with the remainder allocated to growth. These predictions were compared to measurements made on microbial mats that are known to be both nitrogen-limited and populated by actively nitrogen-fixing cyanobacteria. In these mats, under dark, anoxic conditions, 82% of fixed carbon stores were diverted into fermentation. The close agreement between these independent approaches suggests that energy balance models may provide a quantitative means of predicting chemical partitioning within such systems - an important step towards understanding how biological productivity is ultimately partitioned into biosignature compounds.

  13. Energy Efficient Catalytic Activation of Hydrogen peroxide for Green Chemical Processes: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Terrence J.; Horwitz, Colin

    2004-11-12

    A new, highly energy efficient approach for using catalytic oxidation chemistry in multiple fields of technology has been pursued. The new catalysts, called TAML® activators, catalyze the reactions of hydrogen peroxide and other oxidants for the exceptionally rapid decontamination of noninfectious simulants (B. atrophaeus) of anthrax spores, for the energy efficient decontamination of thiophosphate pesticides, for the facile, low temperature removal of color and organochlorines from pulp and paper mill effluent, for the bleaching of dyes from textile mill effluents, and for the removal of recalcitrant dibenzothiophene compounds from diesel and gasoline fuels. Highlights include the following: 1) A 7-log kill of Bacillus atrophaeus spores has been achieved unambiguously in water under ambient conditions within 15 minutes. 2) The rapid total degradation under ambient conditions of four thiophosphate pesticides and phosphonate degradation intermediates has been achieved on treatment with TAML/peroxide, opening up potential applications of the decontamination system for phosphonate structured chemical warfare agents, for inexpensive, easy to perform degradation of stored and aged pesticide stocks (especially in Africa and Asia), for remediation of polluted sites and water bodies, and for the destruction of chemical warfare agent stockpiles. 3) A mill trial conducted in a Pennsylvanian bleached kraft pulp mill has established that TAML catalyst injected into an alkaline peroxide bleach tower can significantly lower color from the effluent stream promising a new, more cost effective, energy-saving approach for color remediation adding further evidence of the value and diverse engineering capacity of the approach to other field trials conducted on effluent streams as they exit the bleach plant. 4) Dibenzothiophenes (DBTs), including 4,6-dimethyldibenzothiophene, the most recalcitrant sulfur compounds in diesel and gasoline, can be completely removed from model gasoline

  14. A hybrid solar and chemical looping combustion system for solar thermal energy storage

    International Nuclear Information System (INIS)

    Highlights: ► A novel solar–CLC hybrid system is proposed which integrates a CLC with solar thermal energy. ► The oxygen carrier particles are used as storage medium for thermal energy storage. ► A solar cavity reactor is proposed for fuel reactor. ► The absorbed solar energy is stored in the particles to produce a base heat load. -- Abstract: A novel hybrid of a solar thermal energy and a chemical looping combustion (CLC) system is proposed here, which employs the oxygen carrier particles in a CLC system to provide diurnal thermal energy storage for concentrated solar thermal energy. In taking advantage of the chemical and sensible energy storage systems that are an inherent part of a CLC system, this hybrid offers potential to achieve cost effective, base load power generation for solar energy. In the proposed system, three reservoirs have been added to a conventional CLC system to allow storage of the oxygen carrier particles, while a cavity solar receiver has been chosen for the fuel reactor. The performance of the system is evaluated using ASPEN PLUS software, with the model being validated using independent simulation result reported previously. Operating temperature, solar efficiency, solar fraction, exergy efficiency and the fraction of the solar thermal energy stored for a based load power generation application are reported.

  15. Chemical composition and metabolizable energy values of feedstuffs for broiler chickens

    OpenAIRE

    Eliane Aparecida da Silva; Luiz Fernando Teixeira Albino; Horacio Santiago Rostagno; Valdir Ribeiro Junior; Rodolfo Alves Vieira; Anastácia Maria de Araújo Campos; Rodrigo Knop Guazzi Messias

    2012-01-01

    The objective of this study was to estimate the values of apparent metabolizable energy and apparent metabolizable energy corrected for nitrogen balance and determine the chemical composition of the following feedstuffs: babassu meal, sunflower meal, corn gluten meal, babassu starch flour, meat and bones meal, beans, millet, cookies residue, pasta residue and bread-making residue. The traditional method of excreta collection was used with broilers in the period of 14 to 24 days of age, which ...

  16. Effect of the chemical cycle on the energy use when producing sulfate pulp

    Energy Technology Data Exchange (ETDEWEB)

    Maripuu, M.

    1982-09-01

    The influence of the chemical cycle on the energy conservation of a sulfate pulp factory has been investigated. The problem concerning ballast (non-load running) is crucial. The operational problems of causticizing and lime reburning have been looked into. Energy use could be reduced by a closer control of ballast, which is difficult to calculate. Heavy losses are found to take place when plant operetions are interfered with.

  17. Significantly enhanced energy output from 3D ordered macroporous structured Fe2O3/Al nanothermite film.

    Science.gov (United States)

    Zhang, Wenchao; Yin, Baoqing; Shen, Ruiqi; Ye, Jiahai; Thomas, Jason A; Chao, Yimin

    2013-01-23

    A three-dimensionally ordered macroporous Fe(2)O(3)/Al nanothermite membrane has been prepared with a polystyrene spheres template. The nanothermite, with an enhanced interfacial contact between fuel and oxidizer, outputs 2.83 kJ g(-1) of energy. This is significantly more than has been reported before. This approach, fully compatible with MEMS technology, provides an efficient way to produce micrometer thick three-dimensionally ordered nanostructured thermite films with overall spatial uniformity. These exciting achievements will greatly facilitate potential for the future development of applications of nanothermites. PMID:23276147

  18. Comparison of Chemical and Microbiological Parameters of Charcoal Versus Gas and Solar Energy Treated Milk

    Directory of Open Access Journals (Sweden)

    Mohamed Osman Mohamed Abdalla

    2010-09-01

    Full Text Available The effect of heat treatment using different sources of heat on the chemical composition and microbial quality of milk was studied. Raw cow, goat and sheep milk were heated with charcoal, gas and solar energy at 99ºC for 12 min, cooled to 20ºC and chemical (fat, protein, total solids, ash (titratable acidity, vitamin C composition as well as microbiological examination (total viable bacteria count were carried out. Results showed that fat, total solids and ash contents w ere high in cow milk heated with solar energy, while protein content was high when milk was heated with gas, and the titratable acidity was high in milk heated with charcoal and gas. The fat, total solids and ash contents of goat milk w ere high when milk was heated with gas, while the protein content and titratable acidity were high when milk was heated with solar energy. The fat contents of sheep milk was high when milk was heated with gas, while the protein and total solids content were high in milk heated with solar energy, and ash content and titratable acidity were high in milk heated with charcoal. Vitamin C content was high for all milks when heated with solar energy, while the total viable bacteria count was high in milks of all species when heated with charcoal. Solar energy was shown to be suitable for heating milk from chemical view point, while heat treatment of milk with gas was found to be better microbiologically.

  19. Hospital ventilation standards and energy conservation: chemical contamination of hospital air. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Rainer, D.; Michaelsen, G.S.

    1980-03-01

    In an era of increasing energy conservation consciousness, a critical reassessment of the validity of hospital ventilation and thermal standards is made. If current standards are found to be excessively conservative, major energy conservation measures could be undertaken by rebalancing and/or modification of current HVAC systems. To establish whether or not reducing ventilation rates would increase airborne chemical contamination to unacceptable levels, a field survey was conducted to develop an inventory and dosage estimates of hospital generated airborne chemical contaminants to which patients, staff, and visitors are exposed. The results of the study are presented. Emphasis is on patient exposure, but an examination of occupational exposure was also made. An in-depth assessment of the laboratory air environment is documented. Housekeeping products used in survey hospitals, hazardous properties of housekeeping chemicals and probable product composition are discussed in the appendices.

  20. On Extraction of Chemical Potentials of Quarks from Particle Transverse Momentum Spectra in High Energy Collisions

    International Nuclear Information System (INIS)

    We present two methods to extract the chemical potentials of quarks in high energy collisions. The first method is based on the ratios of negatively/positively charged particles, and the temperatures extracted from the transverse momentum spectra of related hadrons are needed. The second method is based on the chemical potentials of some particles, and we also need the transverse momentum spectra of related hadrons. To extract the quark chemical potentials, we would like to propose experimental collaborations to measure simultaneously not only the transverse momentum spectra of p-, p, K-, K+, π-, and π+, but also those of D-, D+, B-, and B+ (even those of Δ++, Δ-, and Ω-) in high energy nuclear collisions

  1. The Effective Concepts on Students' Understanding of Chemical Reactions and Energy

    Science.gov (United States)

    Ayyildiz, Yildizay; Tarhan, Leman

    2012-01-01

    The purpose of this study was to determine the relationship between the basic concepts related to the unit of "Chemical Reactions and Energy" and the sub-concepts underlying for meaningful learning of the unit and to investigate the effectiveness of them on students' learning achievements. For this purpose, the basic concepts of the unit were…

  2. A Simple Method to Calculate the Temperature Dependence of the Gibbs Energy and Chemical Equilibrium Constants

    Science.gov (United States)

    Vargas, Francisco M.

    2014-01-01

    The temperature dependence of the Gibbs energy and important quantities such as Henry's law constants, activity coefficients, and chemical equilibrium constants is usually calculated by using the Gibbs-Helmholtz equation. Although, this is a well-known approach and traditionally covered as part of any physical chemistry course, the required…

  3. Quarterly progress report for the Chemical and Energy Research Section of the Chemical Technology Division: January-March 1999

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, R.T.

    1999-11-01

    This reports summarizes the major activities conducted in the Chemical and Energy Research Section of the Chemical Technology Division at Oak Ridge National Laboratory (ORNL) during the period January--March 1999. The section conducts basic and applied research and development in chemical engineering, applied chemistry, and bioprocessing, with an emphasis on energy-driven technologies and advanced chemical separations for nuclear and waste applications. The report describes the various tasks performed within eight major areas of research: Hot Cell Operations, Process Chemistry and Thermodynamics, Molten Salt Reactor Experiment (MSRE) Remediation Studies, Chemistry Research, Separations and Materials Synthesis, Fluid Structure and Properties, Biotechnology Research, and Molecular Studies. The name of a technical contact is included with each task described, and readers are encouraged to contact these individuals if they need additional information. Activities conducted within the area of Hot Cell Operations included column loading of cesium from Melton Valley Storage Tank supematants using an engineered form of crystalline silicotitanate. A second task was to design and construct a continuously stirred tank reactor system to test the Savannah River-developed process of small-tank tetraphenylborate precipitation to remove cesium, strontium, and transuranics from supematant. Within the area of Process Chemistry and Thermodynamics, the problem of solids formation in process solutions from caustic treatment of Hanford sludge was addressed, including issues such as pipeline plugging and viscosity measurements. Investigation of solution conditions required to dissolve Hanford saltcake was also continued. MSRE Remediation Studies focused on recovery of {sup 233}U and its transformation into a stable oxide and radiolysis experiments to permit remediation of MSRE fuel salt. In the area of Chemistry Research, activities included studies relative to molecular imprinting for

  4. Collisions of polyatomic ions with surfaces: incident energy partitioning and chemical reactions

    International Nuclear Information System (INIS)

    Collision of polyatomic ions with surfaces were investigated in ion-surface scattering experiments to obtain more information on energy partitioning in ion-surface collision and on chemical reactions at surfaces. Mass spectra, translation energy and angular distributions of product ions were measured in dependence on the incident energy and the incident angle of polyatomic projectiles. From these data distributions of energy fractions resulting in internal excitation of the projectile, translation energy of the product ions, and energy absorbed by the surface were determined. The surface investigated were a standard stainless steel surface, covered by hydrocarbons, carbon surfaces at room and elevated temperatures, and several surfaces covered by a self-assembled monolayers (C12-hydrocarbon SAM, C11-perfluorohydrocarbon SAM, and C11 hydrocarbon with terminal -COOH group SAM). The main processes observed at collision energies of 10 - 50 eV were: neutralization of the ions at surfaces, inelastic scattering and dissociations of the projectile ions, quasi elastic scattering of the projectile ions, and chemical reactions with the surface material (usually hydrogen-atom transfer reactions). The ion survival factor was estimated to be a few percent for even-electron ions (like protonated ethanol ion, C2H5O+, CD5+) and about 10 - 102 times lower for radical ions (like ethanol and benzene molecular ions, CD4+). In the polyatomic ion -surface energy transfer experiments, the ethanol molecular ion was used as a well-characterized projectile ion. The results with most of the surfaces studied showed in the collision energy range of 13 - 32 eV that most collisions were strongly inelastic with about 6 - 8 % of the incident projectile energy transformed into internal excitation of the projectile (independent of the incident angle) and led partially to its further dissociation in a unimolecular way after the interaction with the surface. The incident energy transformed into the

  5. Number concentration and chemical composition of ultrafine and nanoparticles from WTE (waste to energy) plants.

    Science.gov (United States)

    Cernuschi, Stefano; Giugliano, Michele; Ozgen, Senem; Consonni, Stefano

    2012-03-15

    Stack field testing at four municipal waste-to-energy (WTE) plants was conducted to investigate total number concentrations and size distributions in a size range extended towards the evaluation of ultrafine (UFP) and nanoparticle (NP) fractions with diameters smaller than 100nm and 50nm, respectively. Measurements were performed with a specifically designed sampling line, equipped with a dilution system and a particle counting device for measuring both primary particles in raw flue gases at stack conditions and the contributions of condensable origin, arising from their cooling and dilution immediately following stack release into the atmosphere. Average concentration levels detected ranged between 5×10(3)-6×10(5)cm(-3): for all sampling conditions, ultrafine fractions largely prevailed in number size distributions, with average diameters constantly located in the nanoparticle size range. Stack concentrations appeared to be influenced by the design and process configuration of flue gas cleaning systems, with most significant effects related to the presence of wet scrubbing units and the baghouse operating temperature of dry removal processes. Chemical speciation (i.e., trace metals, anions and cations, carbonaceous compounds) of size-resolved particulate fractions was performed on one of the plants. NP and UFP composition was essentially in accordance with the most important fuel and combustion process characteristics: in particular, the presence of chlorides and metal species was consistent with the respective waste feed content and their expected behavior during combustion and flue gas cleaning processes. PMID:22326138

  6. FEARCF a multidimensional free energy method for investigating conformational landscapes and chemical reaction mechanisms

    Institute of Scientific and Technical Information of China (English)

    NAIDOO Kevin J.

    2012-01-01

    The development and implementation of a computational method able to produce free energies in multiple dimensions,descriptively named the free energies from adaptive reaction coordinate forces (FEARCF) method is described in this paper.While the method can be used to calculate free energies of association,conformation and reactivity here it is shown in the context of chemical reaction landscapes.A reaction free energy surface for the Claisen rearrangement of chorismate to prephenate is used as an illustration of the method's efficient convergence.FEARCF simulations are shown to achieve fiat histograms for complex multidimensional free energy volumes.The sampling efficiency by which it produces multidimensional free energies is demonstrated on the complex puckering of a pyranose ring,that is described by a three dimensional W(θ1,θ2,θ3) potential of mean force.

  7. Energy considerations for steam plasma gasification of black liquor and chemical recovery

    Energy Technology Data Exchange (ETDEWEB)

    Grandy, J.D.; Kong, P.C.

    1995-10-01

    This paper investigates the energy economics of using a hybrid steam plasma process to gasify black liquor. In the pulp and paper industry, gasification is gaining credibility as an incremental method to supplement the standard Kraft process, which bums the black liquor in large furnaces to recover energy and inorganic chemicals (sodium and sulfur) that are recycled back into the wood pulping process. This paper shows that despite the energy intensive nature of steam plasma processing, several fortuitous conditions arise that make it a viable technology for the gasification of black liquor.

  8. Excitation of the aromatic infrared emission bands: Chemical energy in hydrogenated amorphous carbon particles?

    CERN Document Server

    Duley, Walter W

    2011-01-01

    We outline a model for the heating of hydrogenated amorphous (HAC) dust via the release of stored chemical energy and show that this energy (~12 kJ/mole) is sufficient to heat dust grains of classical size (50-1000 {\\AA}) to temperatures at which they can emit at 3.3 {\\mu}m and other "UIR" wavelengths. Using laboratory data, we show that this heating process is consistent with a concentration of a few percent of dangling bonds in HAC and may be initiated by the recombination of trapped H atoms. We suggest that the release of chemical energy from dust represents an additional source of excitation for the UIR bands relaxing the previous requirement that only stochastically heated molecules having fewer than ~ 50 atoms can produce emission at 3.3 {\\mu}m.

  9. Measurement of discrete energy-level spectra in individual chemically synthesized gold nanoparticles

    DEFF Research Database (Denmark)

    Kuemmeth, Ferdinand; Bolotin, Kirill I; Shi, Su-Fei;

    2008-01-01

    We form single-electron transistors from individual chemically synthesized gold nanoparticles, 5-15 nm in diameter, with monolayers of organic molecules serving as tunnel barriers. These devices allow us to measure the discrete electronic energy levels of individual gold nanoparticles that are, by...... virtue of chemical synthesis, well-defined in their composition, size and shape. We show that the nanoparticles are nonmagnetic and have spectra in good accord with random-matrix-theory predictions taking into account strong spin-orbit coupling....

  10. Conventional Quantum Chemical Correlation Energy versus Density-Functional Correlation Energy

    OpenAIRE

    Gross, E.K.U.; Petersilka, M.; Grabo, T.

    1995-01-01

    We analyze the difference between the correlation energy as defined within the conventional quantum chemistry framework and its namesake in density-functional theory. Both quantities are rigorously defined concepts; one finds that $E_c^{QC} \\geq E_c^{DFT}$. We give numerical and analytical arguments suggesting that the numerical difference between the two rigorous quantities is small. Finally, approximate density functional correlation energies resulting from some popular correlation energy f...

  11. Difference in low energy plasma excitation and chemical reactivity of rare gases

    International Nuclear Information System (INIS)

    The gas release behavior of heavy rare gases such as Xe and Kr formed as major fission products in fuel pellets plays an important role on the reliability of fuel claddings due to increase the internal pressure. To clarify the chemical characteristics of rare gases is useful to inhibit the gas release and to improve the radioactive waste management and to the industrial application. On this study, the chemical reactivity was examined using the low energy plasma excitation techniques and oxidation in oxygen atmosphere. Two types of RF sources of the induced couple and static capacity types were used as the low energy plasma source. The electron density in plasma of rare gases was dependent on the binding energy of each gas. The large difference in electron densities among rare gases was typically observed in the induced couple type plasma, because of the high production yield at wall surfaces covered with low energy electrons. It was suggested that the chemical compounds were formed in the condensed atmosphere as fuels tubes. (author)

  12. Lipid Replacement Therapy Drink Containing a Glycophospholipid Formulation Rapidly and Significantly Reduces Fatigue While Improving Energy and Mental Clarity

    Directory of Open Access Journals (Sweden)

    Robert Settineri

    2011-08-01

    Full Text Available Background: Fatigue is the most common complaint of patients seeking general medical care and is often treated with stimulants. It is also important in various physical activities of relatively healthy men and women, such as sports performance. Recent clinical trials using patients with chronic fatigue have shown the benefit of Lipid Replacement Therapy in restoring mitochondrial electron transport function and reducing moderate to severe chronic fatigue. Methods: Lipid Replacement Therapy was administered for the first time as an all-natural functional food drink (60 ml containing polyunsaturated glycophospholipids but devoid of stimulants or herbs to reduce fatigue. This preliminary study used the Piper Fatigue Survey instrument as well as a supplemental questionnaire to assess the effects of the glycophospholipid drink on fatigue and the acceptability of the test drink in adult men and women. A volunteer group of 29 subjects of mean age 56.2±4.5 years with various fatigue levels were randomly recruited in a clinical health fair setting to participate in an afternoon open label trial on the effects of the test drink. Results: Using the Piper Fatigue instrument overall fatigue among participants was reduced within the 3-hour seminar by a mean of 39.6% (p<0.0001. All of the subcategories of fatigue showed significant reductions. Some subjects responded within 15 minutes, and the majority responded within one hour with increased energy and activity and perceived improvements in cognitive function, mental clarity and focus. The test drink was determined to be quite acceptable in terms of taste and appearance. There were no adverse events from the energy drink during the study.Functional Foods in Health and Disease 2011; 8:245-254Conclusions: The Lipid Replacement Therapy functional food drink appeared to be a safe, acceptable and potentially useful new method to reduce fatigue, sustain energy and improve perceptions of mental function.

  13. Biomass as feedstock for chemicals and energy on the threshold of the 21st. century

    International Nuclear Information System (INIS)

    A historical background is first given in which the role of biomass is described in relation to its competition with fossil biomass for the production of chemicals and energy. Occurrences of reserves from both sources are then compared. Petrochemical and biomass routes are then analyzed in terms of their relative competitive advantages. The oleochemical and biotechnology cases are analyzed in more detail as examples of biomass utilization. Latin American examples of industrial manufacturing of biomass derived chemicals are then provided. Alcochemicals are analyzed in detail as well as essential oils and other chemicals. Finally, references are made to regional Latin American initiatives regarding biomass and the objectives, organization and nature of the initiative are presented

  14. Relative significance of heat transfer processes to quantify tradeoffs between complexity and accuracy of energy simulations with a building energy use patterns classification

    Science.gov (United States)

    Heidarinejad, Mohammad

    This dissertation develops rapid and accurate building energy simulations based on a building classification that identifies and focuses modeling efforts on most significant heat transfer processes. The building classification identifies energy use patterns and their contributing parameters for a portfolio of buildings. The dissertation hypothesis is "Building classification can provide minimal required inputs for rapid and accurate energy simulations for a large number of buildings". The critical literature review indicated there is lack of studies to (1) Consider synoptic point of view rather than the case study approach, (2) Analyze influence of different granularities of energy use, (3) Identify key variables based on the heat transfer processes, and (4) Automate the procedure to quantify model complexity with accuracy. Therefore, three dissertation objectives are designed to test out the dissertation hypothesis: (1) Develop different classes of buildings based on their energy use patterns, (2) Develop different building energy simulation approaches for the identified classes of buildings to quantify tradeoffs between model accuracy and complexity, (3) Demonstrate building simulation approaches for case studies. Penn State's and Harvard's campus buildings as well as high performance LEED NC office buildings are test beds for this study to develop different classes of buildings. The campus buildings include detailed chilled water, electricity, and steam data, enabling to classify buildings into externally-load, internally-load, or mixed-load dominated. The energy use of the internally-load buildings is primarily a function of the internal loads and their schedules. Externally-load dominated buildings tend to have an energy use pattern that is a function of building construction materials and outdoor weather conditions. However, most of the commercial medium-sized office buildings have a mixed-load pattern, meaning the HVAC system and operation schedule dictate

  15. Chemical vapour deposition of thermochromic vanadium dioxide thin films for energy efficient glazing

    Energy Technology Data Exchange (ETDEWEB)

    Warwick, Michael E.A. [Department of Chemistry, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London, WC1H 0AJ (United Kingdom); UCL Energy Institute, Central House, 14 Upper Woburn Place, London, WC1H 0NN (United Kingdom); Binions, Russell, E-mail: r.binions@qmul.ac.uk [School of Engineering and Materials Science, Queen Mary University of London, Mile End Road, London, E1 4NS (United Kingdom)

    2014-06-01

    Vanadium dioxide is a thermochromic material that undergoes a semiconductor to metal transitions at a critical temperature of 68 °C. This phase change from a low temperature monoclinic structure to a higher temperature rutile structure is accompanied by a marked change in infrared reflectivity and change in resistivity. This ability to have a temperature-modulated film that can limit solar heat gain makes vanadium dioxide an ideal candidate for thermochromic energy efficient glazing. In this review we detail the current challenges to such glazing becoming a commercial reality and describe the key chemical vapour deposition technologies being employed in the latest research. - Graphical abstract: Schematic demonstration of the effect of thermochromic glazing on solar radiation (red arrow represents IR radiation, black arrow represents all other solar radiation). - Highlights: • Vanadium dioxide thin films for energy efficient glazing. • Reviews chemical vapour deposition techniques. • Latest results for thin film deposition for vanadium dioxide.

  16. Molecular and nanosized catalysts for the conversion of renewables into energy and chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Bianchini, Claudio [Institute of Chemistry of Organometallic Compounds (ICCOM-CNR), Florence (Italy)

    2010-07-01

    The simultaneous conversion of alcohols and sugars into energy (or hydrogen) and chemicals can be accomplished for a variety of renewable alcohols, including ethanol, glycerol and ethylene glycol, by means of two electrochemical devices: direct fuel cells (DAFC) and electrolyzers. In either case, an aqueous solution of the fuel in the anode compartment is oxidized on a nanostructured electrocatalyst that is appropriately designed to promote selectively the partial oxidation of the anolyte with low overpotentials, high stability and fast kinetics. (orig.)

  17. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    OpenAIRE

    Aloisio, R.; Berezinsky, V.; P. Blasi(INAF Arcetri)

    2013-01-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate $X_{max}(E)$ and dispersion $\\sigma(X_{max})$ as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must ...

  18. Nanoelectron spectroscopy for chemical analysis: a novel energy filter for imaging x-ray photoemission spectroscopy

    International Nuclear Information System (INIS)

    A novel instrument for imaging ESCA is described. It is based on a tandem arrangement of two hemispherical energy analysers used as an imaging energy filter. The main spherical aberration (α2-term) of the analyser is corrected by the antisymmetry of the tandem configuration. The kinetic energy range usable for imaging extends up to 1.6 keV; this is compatible with Mg and Al Kα laboratory x-ray sources. First experiments on the chemical surface composition of a Cu0.98Bi0.02 polycrystal, a GaAs/AlGaAs heterostructure and Ag crystallites on Si(111) have been performed using synchrotron radiation. The results reveal an energy resolution of 190 meV and a lateral resolution (edge resolution) of 120 nm. Besides elimination of the analyser's spherical aberration, the tandem arrangement largely retains the time structure of the electron signal, unlike a single hemispherical analyser

  19. Foundations of modeling in cryobiology-I: concentration, Gibbs energy, and chemical potential relationships.

    Science.gov (United States)

    Anderson, Daniel M; Benson, James D; Kearsley, Anthony J

    2014-12-01

    Mathematical modeling plays an enormously important role in understanding the behavior of cells, tissues, and organs undergoing cryopreservation. Uses of these models range from explanation of phenomena, exploration of potential theories of damage or success, development of equipment, and refinement of optimal cryopreservation/cryoablation strategies. Over the last half century there has been a considerable amount of work in bio-heat and mass-transport, and these models and theories have been readily and repeatedly applied to cryobiology with much success. However, there are significant gaps between experimental and theoretical results that suggest missing links in models. One source for these potential gaps is that cryobiology is at the intersection of several very challenging aspects of transport theory: it couples multi-component, moving boundary, multiphase solutions that interact through a semipermeable elastic membrane with multicomponent solutions in a second time-varying domain, during a two-hundred Kelvin temperature change with multi-molar concentration gradients and multi-atmosphere pressure changes. In order to better identify potential sources of error, and to point to future directions in modeling and experimental research, we present a three part series to build from first principles a theory of coupled heat and mass transport in cryobiological systems accounting for all of these effects. The hope of this series is that by presenting and justifying all steps, conclusions may be made about the importance of key assumptions, perhaps pointing to areas of future research or model development, but importantly, lending weight to standard simplification arguments that are often made in heat and mass transport. In this first part, we review concentration variable relationships, their impact on choices for Gibbs energy models, and their impact on chemical potentials. PMID:25240602

  20. Generally applicable limits on intakes of uranium based on its chemical toxicity and the radiological significance of intakes at those limits.

    Science.gov (United States)

    Thorne, M C; Wilson, J

    2015-12-01

    Uranium is chemically toxic and radioactive, and both considerations have to be taken into account when limiting intakes of the element, in the context of both occupational and public exposures. Herein, the most recent information available on the chemical toxicity and biokinetics of uranium is used to propose new standards for limiting intakes of the element. The approach adopted allows coherent standards to be set for ingestion and inhalation of different chemical forms of the element by various age groups. It also allows coherent standards to be set for occupational and public exposures (including exposures of different age groups) and for various exposure regimes (including short-term and chronic exposures). The proposed standards are more restrictive than those used previously, but are less restrictive than the Minimal Risk Levels proposed recently by the US Agency for Toxic Substances and Disease Registry. Having developed a set of proposed limits based solely on chemical toxicity considerations, the radiological implications of exposure at those proposed limits are investigated for natural, depleted and enriched uranium. PMID:26418079

  1. Analysis of Thermal and Chemical Effets on Negative Valve Overlap Period Energy Recovery for Low-Temperature Gasoline Combustion

    Energy Technology Data Exchange (ETDEWEB)

    Ekoto, Dr Isaac [Sandia National Laboratories (SNL); Peterson, Dr. Brian [University of Edinburgh; Szybist, James P [ORNL; Northrop, Dr. William [University of Minnesota

    2015-01-01

    A central challenge for efficient auto-ignition controlled low-temperature gasoline combustion (LTGC) engines has been achieving the combustion phasing needed to reach stable performance over a wide operating regime. The negative valve overlap (NVO) strategy has been explored as a way to improve combustion stability through a combination of charge heating and altered reactivity via a recompression stroke with a pilot fuel injection. The study objective was to analyze the thermal and chemical effects on NVO-period energy recovery. The analysis leveraged experimental gas sampling results obtained from a single-cylinder LTGC engine along with cylinder pressure measurements and custom data reduction methods used to estimate period thermodynamic properties. The engine was fueled by either iso-octane or ethanol, and operated under sweeps of NVO-period oxygen concentration, injection timing, and fueling rate. Gas sampling at the end of the NVO period was performed via a custom dump-valve apparatus, with detailed sample speciation by in-house gas chromatography. The balance of NVO-period input and output energy flows was calculated in terms of fuel energy, work, heat loss, and change in sensible energy. Experiment results were complemented by detailed chemistry single-zone reactor simulations performed at relevant mixing and thermodynamic conditions, with results used to evaluate ignition behavior and expected energy recovery yields. For the intermediate bulk-gas temperatures present during the NVO period (900-1100 K), weak negative temperature coefficient behavior with iso-octane fueling significantly lengthened ignition delays relative to similar ethanol fueled conditions. Faster ethanol ignition chemistry led to lower recovered fuel intermediate yields relative to similar iso-octane fueled conditions due to more complete fuel oxidation. From the energy analysis it was found that increased NVO-period global equivalence ratio, either from lower NVOperiod oxygen

  2. Experimental program to stimulate competitive energy research in North Dakota: Summary and significance of DOE Trainee research

    Energy Technology Data Exchange (ETDEWEB)

    Boudjouk, Philip

    1999-07-01

    The general goals of the North Dakota DOE/EPSCoR Program are to enhance the capabilities of North Dakota's researchers to conduct nationally competitive energy-related research and to develop science and engineering human resources to meet current and future needs in energy-related areas. Doctoral students were trained and energy research was conducted.

  3. Control of charging energy in chemically assembled nanoparticle single-electron transistors

    International Nuclear Information System (INIS)

    We show the control of a charging energy in chemically assembled nanoparticle single-electron transistors (SETs) by altering the core diameter of Au nanoparticles. The charging energy is a fundamental parameter that decides the operating temperature of SETs. Practical application of SETs requires us to regulate the value of the charging energy by tuning the diameter of quantum dots. In this study, we used 3.0, 5.0 and 6.2 nm diameter synthesized Au nanoparticles as a quantum dot in the SETs. The total capacitances and charging energy of the SETs were evaluated from the rhombic Coulomb diamonds attributed to a single Coulomb island. The capacitance and charging energy matched with a concentric sphere model much better than with a simple sphere model. The operating temperatures of the SETs suggested that a charging energy 2.2 times greater than the thermal energy was required for stable operation, in theory. These results will help us to select an appropriate core diameter for the Au nanoparticles in practical SETs. (paper)

  4. How to promote energy conservation in China’s chemical industry

    International Nuclear Information System (INIS)

    Fossil fuel consumption in China’s chemical industry accounted for 19.7% of the total industrial fossil fuel consumption, and the industry has become the second highest energy intensive sector in the country. Therefore, it is extremely urgent and important to study the problems related to fossil fuel consumption in the industry. This paper adopts the factor decomposition and the EG co-integration methods to investigate the influencing factors of fossil energy consumption and measure the saving potential of fossil fuel. The paper concludes that the influencing factors can be divided into positive driving factors (labor productivity effect and sector scale effect) and negative driving factors (energy intensity effect and energy structure effect). Among them, labor productivity and energy intensity are the main factors affecting fossil fuel demand. The largest saving potentials of fossil fuels are predicted to be 23.3 Mtce in 2015 and 70.6 Mtce in 2020 under the middle scenario and 46.8 Mtce in 2015 and 100.5 Mtce in 2020 under the ideal scenario, respectively. Finally, this paper provides some policy implications on fossil fuel conservation. - Highlights: • Labor productivity and energy intensity are crucial driving factors. • The relationship among variables is co-integrated. • The result of the EG co-integration is the same as that of LMDI. • ECM displays the short-term fluctuation of fossil fuel consumption. • Under the scenario analysis, there is a huge energy saving potential

  5. Significant Breakthrough in Industrial Test of the "Methanol to Olefins" Process Developed by Dalian Institute of Chemical Physics, Chinese Academy of Sciences

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ A process of "Methanol or Dimethylether to Olefins" developed by Dalian Institute of Chemical Physics (DICP), designated as the DMTO process, has attained great success in industrial scaling up testing. DICP, by collaborating with the Xinxing Coal Chemical Co., Ltd. of Shaanxi Province and the Luoyang Petrochemical Engineering Co. of the SINOPEC Group, operated successfully a 50t(methanol)/d unit for the conversion of methanol to lower olefins, with a methanol conversion of close to 100%, and a selectivity to lower olefins(ethylene, propylene and butylenes) of higher than 90%. On 23rd August, the industrial test project has passed a state appraisal. The experts of the Appraisal Group, headed by Prof.

  6. Generalized Least Energy of Separation for Desalination and Other Chemical Separation Processes

    Directory of Open Access Journals (Sweden)

    Karan H. Mistry

    2013-05-01

    Full Text Available Increasing global demand for fresh water is driving the development and implementation of a wide variety of seawater desalination technologies driven by different combinations of heat, work, and chemical energy. This paper develops a consistent basis for comparing the energy consumption of such technologies using Second Law efficiency. The Second Law efficiency for a chemical separation process is defined in terms of the useful exergy output, which is the minimum least work of separation required to extract a unit of product from a feed stream of a given composition. For a desalination process, this is the minimum least work of separation for producing one kilogram of product water from feed of a given salinity. While definitions in terms of work and heat input have been proposed before, this work generalizes the Second Law efficiency to allow for systems that operate on a combination of energy inputs, including fuel. The generalized equation is then evaluated through a parametric study considering work input, heat inputs at various temperatures, and various chemical fuel inputs. Further, since most modern, large-scale desalination plants operate in cogeneration schemes, a methodology for correctly evaluating Second Law efficiency for the desalination plant based on primary energy inputs is demonstrated. It is shown that, from a strictly energetic point of view and based on currently available technology, cogeneration using electricity to power a reverse osmosis system is energetically superior to thermal systems such as multiple effect distillation and multistage flash distillation, despite the very low grade heat input normally applied in those systems.

  7. Chemical production from waste carbon monoxide: its potential for energy conservation

    Energy Technology Data Exchange (ETDEWEB)

    Rohrmann, C.A.; Schiefelbein, G.F.; Molton, P.M.; Li, C.T.; Elliott, D.C.; Baker, E.G.

    1977-11-01

    Results of a study of the potential for energy conservation by producing chemicals from by-product or waste carbon monoxide (CO) from industrial sources are summarized. Extensive compilations of both industrial sources and uses for carbon monoxide were developed and included. Reviews of carbon monoxide purification and concentration technology and preliminary economic evaluations of carbon monoxide concentration, pipeline transportation and utilization of CO in the synthesis of ammonia and methanol are included. Preliminary technical and economic feasibility studies were made of producing ammonia and methanol from the by-product CO produced by a typical elemental phosphorus plant. Methanol synthesis appears to be more attractive than ammonia synthesis when using CO feedstock because of reduced water gas shift and carbon dioxide removal requirements. The economic studies indicate that methanol synthesis from CO appears to be competitive with conventional technology when the price of natural gas exceeds $0.82/million Btu, while ammonia synthesis from CO is probably not competitive until the price of natural gas exceeds $1.90/million Btu. It is concluded that there appears to be considerable potential for energy conservation in the chemical industry, by collecting CO rather than flaring it, and using it to make major chemicals such as ammonia and methanol.

  8. Energy and chemical efficient nitrogen removal at a full-scale MBR water reuse facility

    Directory of Open Access Journals (Sweden)

    Jianfeng Wen

    2015-02-01

    Full Text Available With stringent wastewater discharge limits on nitrogen and phosphorus, membrane bioreactor (MBR technology is gaining popularity for advanced wastewater treatment due to higher effluent quality and smaller footprint. However, higher energy intensity required for MBR plants and increased operational costs for nutrient removal limit wide application of the MBR technology. Conventional nitrogen removal requires intensive energy inputs and chemical addition. There are drivers to search for new technology and process control strategies to treat wastewater with lower energy and chemical demand while still producing high quality effluent. The NPXpress is a patented technology developed by American Water engineers. This technology is an ultra-low dissolved oxygen (DO operation for wastewater treatment and is able to remove nitrogen with less oxygen requirements and reduced supplemental carbon addition in MBR plants. Jefferson Peaks Water Reuse Facility in New Jersey employs MBR technology to treat municipal wastewater and was selected for the implementation of the NPXpress technology. The technology has been proved to consistently produce a high quality reuse effluent while reducing energy consumption and supplemental carbon addition by 59% and 100%, respectively. Lab-scale kinetic studies suggested that NPXpress promoted microorganisms with higher oxygen affinity. Process modelling was used to simulate treatment performance under NPXpress conditions and develop ammonia-based aeration control strategy. The application of the ammonia-based aeration control at the plant further reduced energy consumption by additional 9% and improved treatment performance with 35% reduction in effluent total nitrogen. The overall energy savings for Jefferson Peaks was $210,000 in four years since the implementation of NPXpress. This study provided an insight in design and operation of MBR plants with NPXpress technology and ultra-low DO operations.

  9. Biomass use in chemical and mechanical pulping with biomass-based energy supply

    Energy Technology Data Exchange (ETDEWEB)

    Holmberg, Jonas M.; Gustavsson, Leif [Department of Engineering Physics and Mathematics, Mid Sweden University, SE-831 25 Oestersund (Sweden)

    2007-12-15

    The pulp and paper industry is energy intensive and consumes large amounts of wood. Biomass is a limited resource and its efficient use is therefore important. In this study, the total amount of biomass used for pulp and for energy is estimated for the production of several woodfree (containing only chemical pulp) and mechanical (containing mechanical pulp) printing paper products, under Swedish conditions. Chemical pulp mills today are largely self-sufficient in energy while mechanical pulp mills depend on large amounts of external electricity. Technically, all energy used in pulp- and papermaking can be biomass based. Here, we assume that all energy used, including external electricity and motor fuels, is based on forest biomass. The whole cradle-to-gate chain is included in the analyses. The results indicate that the total amount of biomass required per tonne paper is slightly lower for woodfree than for mechanical paper. For the biomass use per paper area, the paper grammage is decisive. If the grammage can be lowered by increasing the proportion of mechanical pulp, this may lower the biomass use per paper area, despite the higher biomass use per unit mass in mechanical paper. In the production of woodfree paper, energy recovery from residues in the mill accounts for most of the biomass use, while external electricity production accounts for the largest part for mechanical paper. Motor fuel production accounts for 5-7% of the biomass use. The biomass contained in the final paper product is 21-42% of the total biomass use, indicating that waste paper recovery is important. The biomass use was found to be about 15-17% lower for modelled, modern mills compared with mills representative of today's average technology. (author)

  10. Energy Transfer from Phycobilisomes to Photosystems of Nostoc flagelliforme Born. et Flah. During the Rewetting Course and Its Physiological Significance

    Institute of Scientific and Technical Information of China (English)

    Hui HUANG; Ke-Zhi BAI; Ze-Pu ZHONG; Liang-Bi LI; Ting-Yun KUANG

    2005-01-01

    During the non-frost season, the condensation of dew makes Nostocflagelliforme Born. et Flah., a highly drought-tolerant terrestrial cyanobacterium, frequently undergo rehydration-dehydration.Rehydration begins in the dark at night. After rewetting in the dark, photochemical activity and the structure of photosystem (PS) Ⅱ were not recovered at all; the structure of PSⅠ, energy transfer in phycobilisomes, and energy transfer from phycobilisomes to PSⅠ were recovered within 5 min, as in the light. The recovery of energy transfer from phycobilisomes to PSⅡ was light dependent and energy transfer from phycobilisomes to PSⅡ was only partially recovered in the dark. These results suggest that the two-trigger control (water and light) of photosynthetic recovery may make N. flagelliforme avoid unnecessary energy consumption and, at the same time, the partial recovery of energy transfer from phycobilisomes to PSⅡ in the dark could help N. flagelliforme accumulate more photosynthetic products during the transient period of rehydrationdehydration.

  11. Predicting corn digestible and metabolizable energy content from its chemical composition in growing pigs

    Institute of Scientific and Technical Information of China (English)

    Quanfeng Li; Jianjun Zang; Dewen Liu; Xiangshu Piao; Changhua Lai; Defa Li

    2014-01-01

    Background:The nutrient composition of corn is variable. To prevent unforeseen reductions in growth performance, grading and analytical methods are used to minimize nutrient variability between calculated and analyzed values. This experiment was carried out to define the sources of variation in the energy content of corn and to develop a practical method to accurately estimate the digestible energy (DE) and metabolisable energy (ME) content of individual corn samples for growing pigs. Twenty samples were taken from each of five provinces in China (Jilin, Hebei, Shandong, Liaoning, and Henan) to obtain a range of quality. Results:The DE and ME contents of the 100 corn samples were measured in 35.3 ± 1.92 kg growing pigs (six pigs per corn sample). Sixty corn samples were used to build the prediction model;the remaining forty samples were used to test the suitability of these models. The chemical composition of each corn sample was determined, and the results were used to establish prediction equations for DE or ME content from chemical characteristics. The mean DE and ME content of the 100 samples were 4,053 and 3,923 kcal/kg (dry matter basis), respectively. The physical characteristics were determined, as well, and the results indicated that the bulk weight and 1,000-kernel weight were not associated with energy content. The DE and ME values could be accurately predicted from chemical characteristics. The best fit equations were as follows:DE, kcal/kg of DM=1062.68+(49.72 × EE)+(0.54 × GE)+(9.11 × starch), with R2=0.62, residual standard deviation (RSD)=48 kcal/kg, and P<0.01;ME, kcal/kg of dry matter basis (DM)=671.54+(0.89 × DE)-(5.57 × NDF)-(191.39 × ash), with R2=0.87, RSD=18 kcal/kg, and P<0.01. Conclusion:This experiment confirms the large variation in the energy content of corn, describes the factors that influence this variation, and presents equations based on chemical measurements that may be used to predict the DE and ME content of individual

  12. Chemical effects induced by low-energy particle beams in fluorozirconate glasses

    International Nuclear Information System (INIS)

    The modification of the chemical structure of fluorozirconate glasses (ZBLAN) with Ar ion and atom beams of low energy (2-10keV) has been studied in comparison with the damage produced in the starting polycrystalline ZrF4 and BaF2. A variety of reduced chemical states of Zr is produced in ZrF4 as well as in ZBLAN glasses, including metallic Zr0State. A strong enhancement of the amount of the metallic Zr formed under irradiation is observed in ZBLAN, while it is present only as trace in the irradiated pure ZrF4 samples. The reported effect is tentatively attributed to the presence of Ba ions in the glass network which could prompt the self-trapping of radiation-induced defects at the Zr sites, involving their progressive reduction

  13. Low energy oxygen ion beam modification of the surface morphology and chemical structure of polyurethane fibers

    International Nuclear Information System (INIS)

    Energetic O+ ions were implanted into polyurethane (PU) fiber filaments, at 60 and 100 keV with doses of 5 x 1014 and 1 x 1015 ions/cm2, to modify the near-surface fiber morphology. The implantations were performed at room temperature and at -197 deg. C, a temperature well below the glass transition temperature for this system. At room temperature, the lower energy implantation heats the fibers primarily near their surface, causing the fiber surface to smoothen and to develop a flattened shape. At the higher energy, the ion beam deposits its energy closer to the fiber core, heating the fiber more uniformly and causing them to re-solidify slowly. This favors a cylindrical equilibrium shape with a smooth fiber surface and no crack lines. The average fiber diameter reduced during 100 keV implantation from 3.1 to 2.3 μm. At -197 deg. C, the ion implantation does not provide enough heat to cause notable physical modifications, but the fibers crack and break during subsequent warming to room temperature. The dose dependence of the crack formation along the fiber intersections is presented. The ion beams further cause near-surface chemical modifications in the fibers, particularly introducing two new chemical functional groups (C-(C=O)-C and C-N-C)

  14. Low energy oxygen ion beam modification of the surface morphology and chemical structure of polyurethane fibers

    Science.gov (United States)

    Wong, K. H.; Zinke-Allmang, M.; Wan, W. K.; Zhang, J. Z.; Hu, P.

    2006-01-01

    Energetic O+ ions were implanted into polyurethane (PU) fiber filaments, at 60 and 100 keV with doses of 5 × 1014 and 1 × 1015 ions/cm2, to modify the near-surface fiber morphology. The implantations were performed at room temperature and at -197 °C, a temperature well below the glass transition temperature for this system. At room temperature, the lower energy implantation heats the fibers primarily near their surface, causing the fiber surface to smoothen and to develop a flattened shape. At the higher energy, the ion beam deposits its energy closer to the fiber core, heating the fiber more uniformly and causing them to re-solidify slowly. This favors a cylindrical equilibrium shape with a smooth fiber surface and no crack lines. The average fiber diameter reduced during 100 keV implantation from 3.1 to 2.3 μm. At -197 °C, the ion implantation does not provide enough heat to cause notable physical modifications, but the fibers crack and break during subsequent warming to room temperature. The dose dependence of the crack formation along the fiber intersections is presented. The ion beams further cause near-surface chemical modifications in the fibers, particularly introducing two new chemical functional groups (C-(Cdbnd O)-C and C-N-C).

  15. The Role of Chemical Processes in the Transition to Sustainable Energy Systems

    International Nuclear Information System (INIS)

    Chemical science and engineering play a central role in improving the eco- efficiency of energy services, be it by optimizing fossil fuel utilization from the source to the sinks, be it by exploring new ways of replacing fossil fuels with renewable ones. Catalytic fuel processing is required for providing clean and easy to convert inputs from contaminated and/or high molecular weight primary resources into efficient energy conversion systems such as advanced combustion engines and fuel cells. The switch from conventional fossil fuel resources to renewables such as solar or biomass requires new approaches in chemical engineering. Efficiency vs. emissions trade-offs for improving the eco-performance of combustion engines need to be optimized with improved understanding of the complex chemistry taking place in flames. New materials for fuel cells and batteries provide a means of making these devices applicable, thereby drastically cutting down on emissions from energy systems. Chemistry is not only involved in fuel processing and conversion, but it is also important at the end of the pipe, i.e. in catalytic emission control devices, in the treatment of hazardous residues from the incineration of waste materials, and in the complex interactions of air pollutants with the biosphere. (author)

  16. The Role of Chemical Processes in the Transition to Sustainable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Stucki, S.; Palumbo, R.; Baltensperger, U.; Boulouchos, K.; Haas, O.; Scherer, G.G.; Siegwolf, R.; Wokaun, A

    2002-01-01

    Chemical science and engineering play a central role in improving the eco- efficiency of energy services, be it by optimizing fossil fuel utilization from the source to the sinks, be it by exploring new ways of replacing fossil fuels with renewable ones. Catalytic fuel processing is required for providing clean and easy to convert inputs from contaminated and/or high molecular weight primary resources into efficient energy conversion systems such as advanced combustion engines and fuel cells. The switch from conventional fossil fuel resources to renewables such as solar or biomass requires new approaches in chemical engineering. Efficiency vs. emissions trade-offs for improving the eco-performance of combustion engines need to be optimized with improved understanding of the complex chemistry taking place in flames. New materials for fuel cells and batteries provide a means of making these devices applicable, thereby drastically cutting down on emissions from energy systems. Chemistry is not only involved in fuel processing and conversion, but it is also important at the end of the pipe, i.e. in catalytic emission control devices, in the treatment of hazardous residues from the incineration of waste materials, and in the complex interactions of air pollutants with the biosphere. (author)

  17. The isotype ZnO/SiC heterojunction prepared by molecular beam epitaxy--A chemical inert interface with significant band discontinuities.

    Science.gov (United States)

    Zhang, Yufeng; Lin, Nanying; Li, Yaping; Wang, Xiaodan; Wang, Huiqiong; Kang, Junyong; Wilks, Regan; Bär, Marcus; Mu, Rui

    2016-01-01

    ZnO/SiC heterojunctions show great potential for various optoelectronic applications (e.g., ultraviolet light emitting diodes, photodetectors, and solar cells). However, the lack of a detailed understanding of the ZnO/SiC interface prevents an efficient and rapid optimization of these devices. Here, intrinsic (but inherently n-type) ZnO were deposited via molecular beam epitaxy on n-type 6H-SiC single crystalline substrates. The chemical and electronic structure of the ZnO/SiC interfaces were characterized by ultraviolet/x-ray photoelectron spectroscopy and x-ray excited Auger electron spectroscopy. In contrast to the ZnO/SiC interface prepared by radio frequency magnetron sputtering, no willemite-like zinc silicate interface species is present at the MBE-ZnO/SiC interface. Furthermore, the valence band offset at the abrupt ZnO/SiC interface is experimentally determined to be (1.2 ± 0.3) eV, suggesting a conduction band offset of approximately 0.8 eV, thus explaining the reported excellent rectifying characteristics of isotype ZnO/SiC heterojunctions. These insights lead to a better comprehension of the ZnO/SiC interface and show that the choice of deposition route might offer a powerful means to tailor the chemical and electronic structures of the ZnO/SiC interface, which can eventually be utilized to optimize related devices. PMID:26976240

  18. Evaluation of various feedstuffs of ruminants in terms of chemical composition and metabolisable energy content

    Directory of Open Access Journals (Sweden)

    Dinesh Kumar

    2015-05-01

    Full Text Available Aim: The aim was to determine the chemical composition and metabolisable energy (ME content of feedstuffs used in ruminant animals using in vitro method. Materials and Methods: A total of 18 feedstuffs used for ruminant feeding including cultivated non-leguminous fodders like maize, sorghum, pearl millet, and oat; leguminous fodders like cowpea and berseem; agro-industrial by-products such as wheat bran, deoiled rice bran, rice polish, wheat straw, and concentrates such as mustard oil cake, groundnut cake, soybean meal, cotton seed cake, grains like maize, oat, wheat, and barley were taken for this study. Chemical compositions and cell wall constituents of test feeds were determined in triplicate. The crude protein (CP content was calculated as nitrogen (N × 6.25. True dry matter digestibility (TDMD, true organic matter digestibility (TOMD, ME, and partitioning factor (PF values were determined by in vitro gas production technique (IVGPT. Results: The CP content of non-leguminous fodders varied from 7.29% (sorghum to 9.51% (maize, but leguminous fodders had less variation in CP. Oilseed cakes/meals had high CP and ether extract (EE content than other feedstuffs except rice polish, which had 12.80% EE. Wheat straw contained highest fiber fractions than the other ingredients. ME content was highest in grains (wheat-12.02 MJ/kg and lowest in wheat straw (4.65 MJ/kg and other roughages. TDMD of grains and oilseed cakes/meals were higher than the fodders and agro-industrial by-products. The same trend was observed for TOMD. Conclusions: It was concluded that the energy feeds showed a great variation in chemical composition and ME content. The results of this study demonstrated that the kinetics of gas production of energy feed sources differed among themselves. Evaluation of various feedstuffs is helpful in balanced ration formulation for field animals and under farm conditions for better utilization of these commonly available feed resources.

  19. Estimated Energy Savings and Financial Impacts of Nanomaterials by Design on Selected Applications in the Chemical Industry

    Energy Technology Data Exchange (ETDEWEB)

    Thayer, Gary R. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Roach, J. Fred [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dauelsberg, Lori [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2006-03-01

    This study provides a preliminary analysis of the potential impact that nanotechnology could have on energy efficiency, economic competitiveness, waste reduction, and productivity, in the chemical and related industries.

  20. Chemical desulfurization of Turkish Cayirhan lignite with HI using microwave and thermal energy

    OpenAIRE

    Elsamak, Gülhan Güllü; Elsamak, Gulhan Gullu; Altuntaş Öztaş, Nurşen; Altuntas Oztas, Nursen; Yürüm, Yuda; Yurum, Yuda

    2003-01-01

    The purpose of the present work was to investigate the effect of the concentration of HI and reaction time in the chemical desulfurization of Cayirhan lignite in a microwave energy set up and to compare the results with those obtained in a thermal heating system. As the concentration of the HI was increased, the extent of desulfurization was also increased in all the experiments done for all of the samples of lignite. The main difference between the thermal and microwave heating was the extre...

  1. Linear solvation energy relationships for toxicity of selected organic chemicals to Daphnia pulex and Daphnia magna

    Science.gov (United States)

    Passino, Dora R.M.; Hickey, James P.; Frank, Anthony M.

    1988-01-01

    In the Laurentian Great Lakes, more than 300 contaminants have been identified in fish, other biota, water, and sediment. Current hazard assessment of these chemicals by the National Fisheries Research Center-Great Lakes is based on their toxicity, occurrence in the environment, and source. Although scientists at the Center have tested over 70 chemicals with the crustacean Daphnia pulex, the number of experimental data needed to screen the huge array of chemicals in the Great Lakes exceeds the practical capabilities of conducting bioassays. This limitation can be partly circumvented, however, by using mathematical models based on quantitative structure-activity relationships (QSAR) to provide rapid, inexpensive estimates of toxicity. Many properties of chemicals, including toxicity, bioaccumulation and water solubility are well correlated and can be predicted by equations of the generalized linear solvation energy relationships (LSER). The equation we used to model solute toxicity is Toxicity = constant + mVI/100 + s (π* + dδ) + bβm + aαm where VI = intrinsic (Van der Waals) molar volume; π* = molecular dipolarity/polarizability; δ = polarizability 'correction term'; βm = solute hydrogen bond acceptor basicity; and αm = solute hydrogen bond donor acidity. The subscript m designates solute monomer values for α and β. We applied the LSER model to 48-h acute toxicity data (measured as immobilization) for six classes of chemicals detected in Great Lakes fish. The following regression was obtained for Daphnia pulex (concentration = μM): log EC50 = 4.86 - 4.35 VI/100; N = 38, r2 = 0.867, sd = 0.403 We also used the LSER modeling approach to analyze to a large published data set of 24-h acute toxicity for Daphnia magna; the following regression resulted, for eight classes of compounds (concentration = mM): log EC50 = 3.88 - 4.52 VI/100 - 1.62 π* + 1.66 βm - 0.916 αm; N = 62, r2 = 0.859, sd = 0.375 In addition we developed computer software that identifies

  2. Task Group report to the Assistant Secretary for Environment, Safety and Health on oversight of chemical safety at the Department of Energy. Volume 2, Appendices

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-01

    This report presents the results of a preliminary review of chemical safety within the Department of Energy (DOE). The review was conducted by Chemical Safety Oversight Review (CSOR) Teams composed of Office of Environment, Safety and Health (EH) staff members and contractors. The primary objective of the CSOR was to assess, the safety status of DOE chemical operations and identify any significant deficiencies associated with such operations. Significant was defined as any situation posing unacceptable risk, that is, imminent danger or threat to workers, co-located workers, the general public, or the environment, that requires prompt action by EH or the line organizations. A secondary objective of the CSOR was to gather and analyze technical and programmatic information related to chemical safety to be used in conjunction with the longer-range EH Workplace Chemical Accident Risk Review (WCARR) Program. The WCARR Program is part of the ongoing EH oversight of nonnuclear safety at all DOE facilities. `` The program objective is to analyze DOE and industry chemical safety programs and performance and determine the need for additional or improved safety guidance for DOE. During the period June 6, 1992, through July 31, 1992, EH conducted CSORs at five DOE sites. The sites visited were Los Alamos National Laboratory (LANL), Savannah River Site (SRS), the Y-12 Plant (Y-12), Oak Ridge National Laboratory (ORNL), and Lawrence Livermore National Laboratory (LLNL).

  3. An isomer-specific high-energy collision-induced dissociation MS/MS database for forensic applications: a proof-of-concept on chemical warfare agent markers.

    Science.gov (United States)

    Subramaniam, Raja; Östin, Anders; Nygren, Yvonne; Juhlin, Lars; Nilsson, Calle; Åstot, Crister

    2011-09-01

    Spectra database search has become the most popular technique for the identification of unknown chemicals, minimizing the need for authentic reference chemicals. In the present study, an isomer-specific high-energy collision-induced dissociation (CID) MS/MS spectra database of 12 isomeric O-hexyl methylphosphonic acids (degradation markers of nerve agents) was created. Phosphonate anions were produced by the electrospray ionization of phosphonic acids or negative-ion chemical ionization of their fluorinated derivatives and were analysed in a hybrid magnetic-sector-time-of-flight tandem mass spectrometer. A centre-of-mass energy (E(com)) of 65 eV led to an optimal sequential carbon-carbon bond breakage, which was interpreted in terms of charge remote fragmentation. The proposed mechanism is discussed in comparison with the routinely used low-energy CID MS/MS. Even-mass (odd-electron) charge remote fragmentation ion series were diagnostic of the O-alkyl chain structure and can be used to interpret unknown spectra. Together with the odd-mass ion series, they formed highly reproducible, isomer-specific spectra that gave significantly higher database matches and probability factors (by 1.5 times) than did the EI MS spectra of the trimethylsilyl derivatives of the same isomers. In addition, ionization by negative-ion chemical ionization and electrospray ionization resulted in similar spectra, which further highlights the general potential of the high-energy CID MS/MS technique. PMID:21915956

  4. Quantum chemical study of mechanisms of dissociation and isomerization reactions in some molecules and radicals of astrophysical significance: Cyanides and related molecules

    Indian Academy of Sciences (India)

    V P Gupta; Archina Sharma

    2006-09-01

    A theoretical study of the mechanism of photodecomposition in carbonyl cyanide, diethynyl ketone, acetyl cyanide and formyl cyanide has been conducted using density functional and MP2 theories. A complete analysis of the electronic spectra of these molecules in terms of nature, energy and intensity of electronic transitions has been provided by time-dependent density functional theory. Mixing coefficients and main configurations of the electronic states have been used to identify the states leading to the photodecomposition process. While the Rydberg state 1(n,3s) is involved in the dissociation of formyl cyanide and acetyl cyanide, the $^{*}_{CC} / ^{*}_{CN}$ states are involved in the case of carbonyl cyanide and diethynyl ketone. In all cases, however, stepwise decomposition process is preferred over the concerted reaction process. Based on potential energy curves for bond dissociation and the transition state and IRC studies, it is found that besides the direct dissociation of carbonyl cyanide, a photoisomerization process through a non-planar transition state may also occur resulting in the formation of a stable and planar isomer CNC(O)CN. A complete vibrational analysis of the higher energy isomer has been conducted and several new fundamental bands are predicted. Some of the earlier experimental results on the photodecomposition mechanism and energies of photofragments in carbonyl cyanide and acetyl cyanide have also been rationalized.

  5. Future US energy demands based upon traditional consumption patterns lead to requirements which significantly exceed domestic supply

    Science.gov (United States)

    1975-01-01

    Energy consumption in the United States has risen in response to both increasing population and to increasing levels of affluence. Depletion of domestic energy reserves requires consumption modulation, production of fossil fuels, more efficient conversion techniques, and large scale transitions to non-fossile fuel energy sources. Widening disparity between the wealthy and poor nations of the world contributes to trends that increase the likelihood of group action by the lesser developed countries to achieve political and economic goals. The formation of anticartel cartels is envisioned.

  6. Chemical controls on fault behavior: weakening of serpentinite sheared against quartz-bearing rocks and its significance for fault creep in the San Andreas system

    Science.gov (United States)

    Moore, Diane E.; Lockner, David A.

    2013-01-01

    The serpentinized ultramafic rocks found in many plate-tectonic settings commonly are juxtaposed against crustal rocks along faults, and the chemical contrast between the rock types potentially could influence the mechanical behavior of such faults. To investigate this possibility, we conducted triaxial experiments under hydrothermal conditions (200-350°C), shearing serpentinite gouge between forcing blocks of granite or quartzite. In an ultramafic chemical environment, the coefficient of friction, µ, of lizardite and antigorite serpentinite is 0.5-0.6, and µ increases with increasing temperature over the tested range. However, when either lizardite or antigorite serpentinite is sheared against granite or quartzite, strength is reduced to µ ~ 0.3, with the greatest strength reductions at the highest temperatures (temperature weakening) and slowest shearing rates (velocity strengthening). The weakening is attributed to a solution-transfer process that is promoted by the enhanced solubility of serpentine in pore fluids whose chemistry has been modified by interaction with the quartzose wall rocks. The operation of this process will promote aseismic slip (creep) along serpentinite-bearing crustal faults at otherwise seismogenic depths. During short-term experiments serpentine minerals reprecipitate in low-stress areas, whereas in longer experiments new Mg-rich phyllosilicates crystallize in response to metasomatic exchanges across the serpentinite-crustal rock contact. Long-term shear of serpentinite against crustal rocks will cause the metasomatic mineral assemblages, which may include extremely weak minerals such as saponite or talc, to play an increasingly important role in the mechanical behavior of the fault. Our results may explain the distribution of creep on faults in the San Andreas system.

  7. A new type of power energy for accelerating chemical reactions: the nature of a microwave-driving force for accelerating chemical reactions.

    Science.gov (United States)

    Zhou, Jicheng; Xu, Wentao; You, Zhimin; Wang, Zhe; Luo, Yushang; Gao, Lingfei; Yin, Cheng; Peng, Renjie; Lan, Lixin

    2016-01-01

    The use of microwave (MW) irradiation to increase the rate of chemical reactions has attracted much attention recently in nearly all fields of chemistry due to substantial enhancements in reaction rates. However, the intrinsic nature of the effects of MW irradiation on chemical reactions remains unclear. Herein, the highly effective conversion of NO and decomposition of H2S via MW catalysis were investigated. The temperature was decreased by several hundred degrees centigrade. Moreover, the apparent activation energy (Ea') decreased substantially under MW irradiation. Importantly, for the first time, a model of the interactions between microwave electromagnetic waves and molecules is proposed to elucidate the intrinsic reason for the reduction in the Ea' under MW irradiation, and a formula for the quantitative estimation of the decrease in the Ea' was determined. MW irradiation energy was partially transformed to reduce the Ea', and MW irradiation is a new type of power energy for speeding up chemical reactions. The effect of MW irradiation on chemical reactions was determined. Our findings challenge both the classical view of MW irradiation as only a heating method and the controversial MW non-thermal effect and open a promising avenue for the development of novel MW catalytic reaction technology. PMID:27118640

  8. A new type of power energy for accelerating chemical reactions: the nature of a microwave-driving force for accelerating chemical reactions

    Science.gov (United States)

    Zhou, Jicheng; Xu, Wentao; You, Zhimin; Wang, Zhe; Luo, Yushang; Gao, Lingfei; Yin, Cheng; Peng, Renjie; Lan, Lixin

    2016-01-01

    The use of microwave (MW) irradiation to increase the rate of chemical reactions has attracted much attention recently in nearly all fields of chemistry due to substantial enhancements in reaction rates. However, the intrinsic nature of the effects of MW irradiation on chemical reactions remains unclear. Herein, the highly effective conversion of NO and decomposition of H2S via MW catalysis were investigated. The temperature was decreased by several hundred degrees centigrade. Moreover, the apparent activation energy (Ea’) decreased substantially under MW irradiation. Importantly, for the first time, a model of the interactions between microwave electromagnetic waves and molecules is proposed to elucidate the intrinsic reason for the reduction in the Ea’ under MW irradiation, and a formula for the quantitative estimation of the decrease in the Ea’ was determined. MW irradiation energy was partially transformed to reduce the Ea’, and MW irradiation is a new type of power energy for speeding up chemical reactions. The effect of MW irradiation on chemical reactions was determined. Our findings challenge both the classical view of MW irradiation as only a heating method and the controversial MW non-thermal effect and open a promising avenue for the development of novel MW catalytic reaction technology. PMID:27118640

  9. Significant enhancement of the electrical transport properties of graphene films by controlling the surface roughness of Cu foils before and during chemical vapor deposition

    Science.gov (United States)

    Lee, Dongmok; Kwon, Gi Duk; Kim, Jung Ho; Moyen, Eric; Lee, Young Hee; Baik, Seunghyun; Pribat, Didier

    2014-10-01

    We have studied the influence of the surface roughness of copper foils on the sheet resistance of graphene sheets grown by chemical vapor deposition. The surface roughness of the copper foils was reproducibly controlled by electropolishing. We have found that the graphene sheet resistance monotonically decreases as the surface roughness of the copper foils decreases. We show that a pre-annealing treatment combined with an optimized electropolishing process of the Cu foils and a fast CVD growth prevents the evolution of the Cu surface roughness during graphene synthesis. This combination of fabrication conditions produces small grain polycrystalline graphene films with a sheet resistance of 210 Ω □-1 and carrier mobility values as high as 5450 cm2 V-1 s-1 after transfer onto SiO2/Si.We have studied the influence of the surface roughness of copper foils on the sheet resistance of graphene sheets grown by chemical vapor deposition. The surface roughness of the copper foils was reproducibly controlled by electropolishing. We have found that the graphene sheet resistance monotonically decreases as the surface roughness of the copper foils decreases. We show that a pre-annealing treatment combined with an optimized electropolishing process of the Cu foils and a fast CVD growth prevents the evolution of the Cu surface roughness during graphene synthesis. This combination of fabrication conditions produces small grain polycrystalline graphene films with a sheet resistance of 210 Ω □-1 and carrier mobility values as high as 5450 cm2 V-1 s-1 after transfer onto SiO2/Si. Electronic supplementary information (ESI) available: Developed AFM profiles, evaporation induced planarization effect of Cu foils, EBSD analysis of a polycrystalline Cu foils, XPS spectra on RAW, EP and O-EP samples, Raman area map of the D-to-G mode intensity ratio of A-EP sample, Evaluation of the sheet resistance variation as a function of grain size, Optical images of a Cu foil before and after

  10. Nuclear and energies Nr 59/June 2012 - Synthesis of significant events from December 2011 until May 2012

    International Nuclear Information System (INIS)

    A first article comments the fact that, fifteen months after the Fukushima accident, two reactors are about to start again. In two articles dealing with energy, a first one comments the recent evolution of the energy sector (oil market, gas market, European energy) and a second one addresses current events in the sector of renewable energies: in the solar sector (the Photowatt affair, the Myrte and STARS projects), in the offshore wind sector (bidding in France and in Great-Britain). Dealing with the nuclear sector, a first article deals with the uranium market (from mine to fuel) and with AREVA activities in different countries. A second article proposes an overview of world perspectives for nuclear reactors, of nuclear activity in France (energy policy, nuclear safety, the issue of the Fessenheim power station, the EPR in Flamanville, the ATMEA project) and in various countries in Europe (Finland, Great Britain, Germany, Lithuania, Netherlands, Russia, Belarus, Czech Republic, Poland, Switzerland, Spain, Romania), in the United States, China, South Korea, Japan, India, Armenia, Vietnam, Jordan, and South Africa. The last articles address the relationship between nuclear and society (during the presidential campaign in France, in different reports, in the summit on nuclear safety, in Germany where phasing out nuclear raises problems), the impact of nuclear on the environment (situation in France, incidents in different French nuclear installations, and briefly in other countries like Germany, Great-Britain, Spain, Eastern Europe, Ukraine, Iran, China, Japan, Taiwan, USA), and the development of Pb-212-based radio-immunotherapy by Areva Med

  11. Performance and cost of energy transport and storage systems for dish applications using reversible chemical reactions

    Science.gov (United States)

    Schredder, J. M.; Fujita, T.

    1984-01-01

    The use of reversible chemical reactions for energy transport and storage for parabolic dish networks is considered. Performance and cost characteristics are estimated for systems using three reactions (sulfur-trioxide decomposition, steam reforming of methane, and carbon-dioxide reforming of methane). Systems are considered with and without storage, and in several energy-delivery configurations that give different profiles of energy delivered versus temperature. Cost estimates are derived assuming the use of metal components and of advanced ceramics. (The latter reduces the costs by three- to five-fold). The process that led to the selection of the three reactions is described, and the effects of varying temperatures, pressures, and heat exchanger sizes are addressed. A state-of-the-art survey was performed as part of this study. As a result of this survey, it appears that formidable technical risks exist for any attempt to implement the systems analyzed in this study, especially in the area of reactor design and performance. The behavior of all components and complete systems under thermal energy transients is very poorly understood. This study indicates that thermochemical storage systems that store reactants as liquids have efficiencies below 60%, which is in agreement with the findings of earlier investigators.

  12. Chemical structure changes of thermal-insulating polymers by exposures to high-energy ions

    International Nuclear Information System (INIS)

    The space machines on the low altitude orbits of the earth fly in the dilute atmospheric plasma formed by solar ultraviolet ray. Recently it has become a problem that to the insulators on spaceship surfaces that are charged negatively, the metallic parts attached to high voltage solar cell panels and their peripheral insulators, high energy ions collide, and deteriorate those materials. In this research, high energy ion beam irradiation test was carried out on the heat-resistant polymers for space use, and the change in their chemical structure was examined by XPS, thus the deterioration mechanism was presumed. The ECR ion source was used for ion acceleration, the kinds of generated ions were oxygen and nitrogen, and the irradiated ion energy was up to about 5 keV. The structures of three kinds of the polymers used for this research are shown. In this experiment, after the irradiation of ion beam, the samples were held for one hour in argon gas, and analyzed by XPS in the atmosphere. The XPS spectra of polyimide, PEEK and PFA are shown. It was presumed that by the irradiation of ion beam, on the surfaces of samples, both formation and dropping-off of functional groups occur. According to the energy and dose of irradiated ions, either effect becomes dominant, and the increase or decrease of functional groups occurs. By this change of structure, the lowering of heat resistance is expected. (K.I.)

  13. Indonesia-China Energy Trade: Analyzing Global and Domestic Political Economic Significance in Indonesia-China LNG Trade

    OpenAIRE

    Badaruddin, Muhammad

    2013-01-01

    Indonesia had been the largest LNG exporter for almost three decades since 1977 to 2005. During 1970s and 1980s, Indonesia’s energy industry boosted its economic growth that valued 80% of the country’s annual exports and 70% of its annual revenues. Meanwhile, Indonesia presents an exceptional case since it decreases its LNG export while it has been developing its largest LNG plant in Tangguh due to prioritizing domestic energy demand. But, since Indonesia eagerly links its economy to China, i...

  14. Carbon Dioxide Extraction from the Atmosphere Through Engineered Chemical Sinkage: Enabling Energy and Environmental Security

    Science.gov (United States)

    Dubey, M. K.; Ziock, H.; Rueff, G.; Smith, W. S.; Colman, J.; Elliott, S.; Lackner, K.; Johnston, N. A.

    2002-05-01

    We present the case for carbon dioxide (CO2) extraction from air using engineered chemical sinks as a means of sustaining fossil energy use by avoiding climate change. Existing carbon sequestration strategies such as CO2 injection into geologic formations or the deep ocean and mineral carbonation, require a pure stream of concentrated CO2 to be viable. Furthermore, current emphasis on reducing the global CO2 emissions is on large centralized power plants. However, more than half of all emissions are from the transportation sector and small, distributed sources such as home heating, etc. Most solutions for dealing with these sources explicitly or implicitly entail completely overhauling the existing infrastructure. To solve these problems, Los Alamos National Laboratory has conceived a novel approach for directly extracting CO2 from the atmosphere. Direct extraction converts the dilute CO2 (370 parts per million) in the atmosphere into a pure CO2 stream ready for permanent sequestration. It provides the following advantages: (1) Preserves our existing energy use and fuel distribution systems, which represent a large investment, (2) Indirectly captures CO2 from the myriad of small, distributed, and mobile sources that otherwise are not accessible to sequestration, (3) Allows atmospheric CO2 levels to be restored to their pre-industrial age value, (4) Provides free transport of CO2 to suitable sequestration sites by using natural atmospheric circulation, and (5) Is relatively compact and therefore inexpensive when compared to renewable concepts. Our concept harnesses atmospheric circulation to transport CO2 to sites where the CO2 is extracted by binding it to an adsorbent. The bound CO2 is then recovered as pure gas by heating together with the solid adsorbent that is recycled. As a proof of concept, we show that an aqueous Ca(OH)2 solution efficiently converts CO2 to a CaCO3 solid that can be heated to obtain pure CO2 and recover the CaO. Even with recycling costs

  15. Effects of mixing energy and flow dynamics on chemical dispersion of crude oil. Volume 1

    International Nuclear Information System (INIS)

    Oil spills at sea can be treated with chemical dispersants to reduce the oil-water interfacial tension and facilitate entrainment of the oil into the water column as small droplets. Removing the floating oil protects surface-swelling organisms and sensitive shorelines. The environmental impacts can be further minimized if the dispersed oil droplets can be diluted into a sufficiently large volume of water by turbulent diffusion. Therefore, this study investigated the effects of mixing energy and mixing systems on dispersion effectiveness of Mars crude oil using 2 bench-scale experimental systems. Two dispersant HLB (hydrophile-lipofile balance) of 10 and 12 were tested for size distribution and dispersed oil droplets. Dispersion effectiveness was defined as the volume of mass fraction of floating oil that becomes entrained in the water column after mixing energy is introduced. The size distribution of the dispersed oil droplets provides another measure of dispersion effectiveness since smaller oil droplets have a stronger tendency to remain suspended in the water column. In this study, dispersion effectiveness was measured at 4 different energy dissipation rates in 2 different mixing systems, namely a baffled flask system and a paddle jar system. It was shown that even when the average energy dissipation rate was the same, the fluid flow dynamics were quite different in the two systems. The droplet-size distributions were multimodal, with 2 major modes occurring in dispersions produced in the baffled-flask system. The diameters of mean volume of the major modes were not found to be sensitive to changes in the energy dissipation rates. However, in the baffled-flask system, the distribution of oil among the modes was influenced by the energy dissipation rate. 25 refs., 5 figs

  16. Effects of mixing energy and flow dynamics on chemical dispersion of crude oil. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, B.; Wrenn, B.A. [Washington Univ., St. Louis, MO (United States). Dept. of Energy, Environment and Chemical Engineering

    2007-07-01

    Oil spills at sea can be treated with chemical dispersants to reduce the oil-water interfacial tension and facilitate entrainment of the oil into the water column as small droplets. Removing the floating oil protects surface-swelling organisms and sensitive shorelines. The environmental impacts can be further minimized if the dispersed oil droplets can be diluted into a sufficiently large volume of water by turbulent diffusion. Therefore, this study investigated the effects of mixing energy and mixing systems on dispersion effectiveness of Mars crude oil using 2 bench-scale experimental systems. Two dispersant HLB (hydrophile-lipofile balance) of 10 and 12 were tested for size distribution and dispersed oil droplets. Dispersion effectiveness was defined as the volume of mass fraction of floating oil that becomes entrained in the water column after mixing energy is introduced. The size distribution of the dispersed oil droplets provides another measure of dispersion effectiveness since smaller oil droplets have a stronger tendency to remain suspended in the water column. In this study, dispersion effectiveness was measured at 4 different energy dissipation rates in 2 different mixing systems, namely a baffled flask system and a paddle jar system. It was shown that even when the average energy dissipation rate was the same, the fluid flow dynamics were quite different in the two systems. The droplet-size distributions were multimodal, with 2 major modes occurring in dispersions produced in the baffled-flask system. The diameters of mean volume of the major modes were not found to be sensitive to changes in the energy dissipation rates. However, in the baffled-flask system, the distribution of oil among the modes was influenced by the energy dissipation rate. 25 refs., 5 figs.

  17. Effects of mixing energy and flow dynamics on chemical dispersion of crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, B.; Wrenn, B.A. [Washington Univ., St. Louis, MO (United States). Dept. of Energy, Environment and Chemical Engineering

    2007-07-01

    Oil spills at sea can be treated with chemical dispersants to reduce the oil-water interfacial tension and facilitate entrainment of the oil into the water column as small droplets. Removing the floating oil protects surface-swelling organisms and sensitive shorelines. The environmental impacts can be further minimized if the dispersed oil droplets can be diluted into a sufficiently large volume of water by turbulent diffusion. Therefore, this study investigated the effects of mixing energy and mixing systems on dispersion effectiveness of Mars crude oil using 2 bench-scale experimental systems. Two dispersant HLB (hydrophile-lipofile balance) of 10 and 12 were tested for size distribution and dispersed oil droplets. Dispersion effectiveness was defined as the volume of mass fraction of floating oil that becomes entrained in the water column after mixing energy is introduced. The size distribution of the dispersed oil droplets provides another measure of dispersion effectiveness since smaller oil droplets have a stronger tendency to remain suspended in the water column. In this study, dispersion effectiveness was measured at 4 different energy dissipation rates in 2 different mixing systems, namely a baffled flask system and a paddle jar system. It was shown that even when the average energy dissipation rate was the same, the fluid flow dynamics were quite different in the two systems. The droplet-size distributions were multimodal, with 2 major modes occurring in dispersions produced in the baffled-flask system. The diameters of mean volume of the major modes were not found to be sensitive to changes in the energy dissipation rates. However, in the baffled-flask system, the distribution of oil among the modes was influenced by the energy dissipation rate. 25 refs., 5 figs.

  18. Elementary electron-molecule interactions and negative ion resonances at subexcitation energies and their significance in gaseous dielectrics

    International Nuclear Information System (INIS)

    Recent knowledge on low-energy (mostly approximately less than 10 eV) electron-molecule interaction processes in dilute and in dense gases is synthesized, discussed, and related to the breakdown strength of gaseous dielectrics. Optimal design of multicomponent gaseous insulators can be made on the basis of such knowledge

  19. Fate and possible nutritional and toxicological significance of methylbromide residues in fumigated cocoa beans. Coordinated programme on isotopic tracer-aided studies on foreign chemical residues in food

    International Nuclear Information System (INIS)

    Methyl bromide residues in cocoa as a result of fumigation under practical conditions have been studied. Cocoa beans were exposed to 14C-labelled CH3Br for 24 hours at 20-32degC and dosage 23.5 to 28mg/1 of fumigants (moisture content of 6-7%). Whole unroasted beans and their shells and nibs as well as shells and nibs of roasted (105degC for 30 min) beans were extracted separately with toluene (for free CH3Br) and the dried residues wet combusted. 14C-activities were determined by liquid scintillation counting. Total methyl bromide (bound and free) was equivalent 83-98ppm in whole unroasted beans 35 hours after treatment and aeration, and 31, 15 and 10ppm after 7, 42 and 70 days respectively in one set of experiments and 37, 53 and 42ppm after 76, 60 and 51 days in another set. Approximately 80% of the residue occurred in the shells which constitute only 12 to 13% of unroasted beans. 99% of the total residues appeared to be in chemically-bound form. Roasting reduced the total residues by 32 to 62% in nibs and 3.6 to 14% in shells. A striking effect of roasting was the occurrence in roasted nibs of residues as (extractable) carbon-14 (62-82% of the total residues compared to 16.5 - 27% in unroasted nibs). The bound residues behaved as methylated derivatives whilst the volatile fraction behaved as volatile aroma compounds formed by Maillard type reactions from the 14C-labelled amino acides and sugars

  20. Chemical reaction of sputtered Cu film with PI modified by low energy reactive atomic beam

    International Nuclear Information System (INIS)

    Polyimide (PMDA-ODA) surface was irradiated by low energy reactive atomic beam with energy 160-180 eV to enhance the adhesion with metal Cu film. O2+ and N2+ ions were irradiated at the fluence from 5 x 1015 to 1 x 1018 cm-2. Wetting angle 78o of distilled deionized (DI) water for bare PI was greatly reduced down to 2-4o after critical ion flounce, and the surface energy was increased from 37 to 81.2 erg/cm. From the analysis of O 1s core-level XPS spectra, such improvement seemed to result from the increment of hydrophilic carbonyl oxygen content on modified PI surface. To see more carefully correlation of the peel strength with interfacial reaction between Cu and PI, flexible copper clad laminate with Cu (9 μm)/Cu (200 nm) on modified PI substrate (25 μm) was fabricated by successive sputtering and electroplating. Firstly, peel strength was measured by using t-test and it was largely increased from 0.2 to 0.5 kgf/cm for Ar+ only irradiated PI to 0.72-0.8 kgf/cm for O2+ or N2O+ irradiated PI. Chemical reaction at the interface was reasoned by analyzing C 1s, O 1s, N 1s, and Cu 2p core-level X-ray photoelectron spectroscopy over the as-cleaved Cu-side and PI side surface through depth profiling. From the C 1s spectra of cleaved Cu-side, by the electron transfer from Cu to carbonyl oxygen, carbonyl carbon atom became less positive and as a result shifted to lower binding energy not reaching the binding energy of C2 and C3. The binding energy shift of the peak C4 as small as 1.7 eV indicates that carbonyl oxygen atoms were not completely broken. From the analysis of the O 1s spectra, it was found that new peak at 530.5 eV (O3) was occurred and the increased area of the peak O3 was almost the same with reduced area of the peak carbonyl oxygen peak O1. Since there was no change in the relative intensity of ether oxygen (O2) to carbonyl oxygen (O1), and thus O3 was believed to result from Cu oxide formation via a local bonding of Cu with carbonyl oxygen atoms

  1. Chemical composition and metabolizable energy values of feedstuffs for broiler chickens

    Directory of Open Access Journals (Sweden)

    Eliane Aparecida da Silva

    2012-03-01

    Full Text Available The objective of this study was to estimate the values of apparent metabolizable energy and apparent metabolizable energy corrected for nitrogen balance and determine the chemical composition of the following feedstuffs: babassu meal, sunflower meal, corn gluten meal, babassu starch flour, meat and bones meal, beans, millet, cookies residue, pasta residue and bread-making residue. The traditional method of excreta collection was used with broilers in the period of 14 to 24 days of age, which were distributed in a completely randomized design with eleven treatments and six replicates of six birds each. Each feedstuff replaced the reference diet at levels of 30 or 40% depending on the type of feedstuff. Chicks were housed in cages fitted with trays to collect the excreta. The apparent metabolizable energy corrected for nitrogen balance (kcal/kg on the natural matter of feedstuffs were: babassu meal, 1,116; sunflower meal, 1,607; corn gluten meal, 3,826; babassu flour starch, 1,731; meat and bone flour, 2,524; common beans, 693; millet, 3,046; cookies residue, 3,351; pasta residue, 3,543 and bread-making residue, 3,494.

  2. Assessment of quantum chemical methods and basis sets for excitation energy transfer

    International Nuclear Information System (INIS)

    The validity of several standard quantum chemical approaches and other models for the prediction of exciton energy transfer is investigated using the HOMO-LUMO excited states of benzene dimer as an example. The configuration interaction singles (CIS), time-dependent Hartree-Fock (TD-HF), time dependent density functional theroy (TD-DFT), and complete-active-space self-consistent-field (CASSCF) methods are applied with a supermolecule approach and compared to the previously established monomer transition density method and the ideal dipole approximation. Strong and physically incorrect admixture of charge-transfer states makes TD-DFT inappropriate for investigations of potential energy surfaces in such dimer systems. CIS, TD-HF and CASSCF perform qualitatively correct. TD-HF seems to be a particularly appropriate method due to its general applicability and overall good performance for the excited state and for transition properties. Double-zeta basis sets with polarisation functions are found to be sufficient to predict transfer rates of dipole allowed excitations. Efficient excitation energy transfer is predicted between degenerate excited states while avoided curve crossings of nearly spaced π-aggregates are identified as a possible trapping mechanism

  3. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    International Nuclear Information System (INIS)

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate Xmax(E) and dispersion σ(Xmax) as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must be very hard, ∼ E-γ with γ∼ 1- 1.6; b) the maximum energy of nuclei of charge Z in the sources must be ∼ 5Z× 1018 eV, thereby not requiring acceleration to extremely high energies; c) the fit to the Auger spectrum can be obtained only at the price of adding an ad hoc light extragalactic component with a steep injection spectrum ∼ E-2.7). In this sense, at the ankle EA≈ 5× 1018 eV) all the components are of extragalactic origin, thereby suggesting that the transition from Galactic to extragalactic cosmic rays occurs below the ankle. Interestingly, the additional light extragalactic component postulated above compares well, in terms of spectrum and normalization, with the one recently measured by KASCADE-Grande

  4. Ultra high energy cosmic rays: implications of Auger data for source spectra and chemical composition

    Energy Technology Data Exchange (ETDEWEB)

    Aloisio, R.; Blasi, P. [INAF/Osservatorio Astrofisico di Arcetri, Largo E. Fermi, 5—50125 Firenze (Italy); Berezinsky, V., E-mail: aloisio@arcetri.astro.it, E-mail: berezinsky@lngs.infn.it, E-mail: blasi@arcetri.astro.it [Gran Sasso Science Institute (INFN), viale F. Crispi 7, 67100 L' Aquila (Italy)

    2014-10-01

    We use a kinetic-equation approach to describe the propagation of ultra high energy cosmic ray protons and nuclei and calculate the expected spectra and mass composition at the Earth for different assumptions on the source injection spectra and chemical abundances. When compared with the spectrum, the elongation rate X{sub max}(E) and dispersion σ(X{sub max}) as observed with the Pierre Auger Observatory, several important consequences can be drawn: a) the injection spectra of nuclei must be very hard, ∼ E{sup -γ} with γ∼ 1- 1.6; b) the maximum energy of nuclei of charge Z in the sources must be ∼ 5Z× 10{sup 18} eV, thereby not requiring acceleration to extremely high energies; c) the fit to the Auger spectrum can be obtained only at the price of adding an ad hoc light extragalactic component with a steep injection spectrum ∼ E{sup -2.7}). In this sense, at the ankle E{sub A}≈ 5× 10{sup 18} eV) all the components are of extragalactic origin, thereby suggesting that the transition from Galactic to extragalactic cosmic rays occurs below the ankle. Interestingly, the additional light extragalactic component postulated above compares well, in terms of spectrum and normalization, with the one recently measured by KASCADE-Grande.

  5. High-energy heavy ion irradiation effects on polymer materials. Localization of chemical reaction by different chemical structures

    International Nuclear Information System (INIS)

    High-energy ion beams (He, C, Ne, Mg, Si Ar, Fe, Kr, Xe) from MEXP port in Heavy Ion Medical Accelerator in Chiba (HIMAC) were irradiated to various fluorinated polymers such as polytetrafluoroethylene (PTFE) and poly (ethylene-co-tetrafluoroethylene) (ETFE) under vacuum at room temperature (RT). The microfabrication of PTFE, FEP and PFA were demonstrated by direct etching using various high energy heavy ion beams. The etching rates of PTFE showed about 0.46 x 10-13 μm/(n/cm2)-1.5 x 10-13 μm/(n/cm2). Moreover, a novel functionally-gradient polymer electorate fuel cell membrane was fabricated with high energy heavy ion beam irradiation due to gradient energy deposition. (author)

  6. Effect of aging on surface chemical bonds of PTFE irradiated by low energy Ti ion

    International Nuclear Information System (INIS)

    Polytetrafluoroethylene (PTFE) was irradiated by low energy titanium ion in a metal vapor vacuum arc (MEVVA) implanter. The samples were irradiated with 80 keV Ti ion with fluences from 5x1015 to 5x1017 Ti/cm2, respectively. Transportation of Ion in Matters (TRIM) code was employed to simulate Ti ion irradiation. The as-irradiated samples were investigated by ESCA, SEM and wettability. As increasing ion fluence, various chemical bonds and irradiation-damaged surfaces were observed. The water droplet contact angel of PTFE samples increased gradually with ion fluence. All the as-irradiated PTFE samples were aged in air for 1 year. After aging the surface-restructuring behavior was observed on the surfaces of the samples irradiated with ion fluence equal to or less than 5x1016 Ti/cm2, which resulted in decrease of the droplet contact angle of these samples. The surface roughness change of the aged samples, which were measured by atomic force microscopy (AFM), was consistent with the droplet contact angle change. The experimental results revealed that Ti ion fluence closely affected the surface chemical bond, morphology and wettability, as well as the aging stability of the as-irradiated PTFE samples

  7. Molecular Dynamics Study of Thermally Augmented Nanodroplet Motion on Chemical Energy Induced Wettability Gradient Surfaces.

    Science.gov (United States)

    Chakraborty, Monojit; Chowdhury, Anamika; Bhusan, Richa; DasGupta, Sunando

    2015-10-20

    Droplet motion on a surface with chemical energy induced wettability gradient has been simulated using molecular dynamics (MD) simulation to highlight the underlying physics of molecular movement near the solid-liquid interface including the contact line friction. The simulations mimic experiments in a comprehensive manner wherein microsized droplets are propelled by the surface wettability gradient against forces opposed to motion. The liquid-wall Lennard-Jones interaction parameter and the substrate temperature are varied to explore their effects on the three-phase contact line friction coefficient. The contact line friction is observed to be a strong function of temperature at atomistic scales, confirming their experimentally observed inverse functionality. Additionally, the MD simulation results are successfully compared with those from an analytical model for self-propelled droplet motion on gradient surfaces. PMID:26381847

  8. Single-collision studies of hot atom energy transfer and chemical reaction

    International Nuclear Information System (INIS)

    This report discusses research in the collision dynamics of translationally hot atoms, with funding with DOE for the project ''Single-Collision Studies of Hot Atom Energy Transfer and Chemical Reaction,'' Grant Number DE-FG03-85ER13453. The work reported here was done during the period September 9, 1988 through October 31, 1991. During this period this DOE-funded work has been focused on several different efforts: (1) experimental studies of the state-to-state dynamics of the H + RH → H2 R reactions where RH is CH4, C2H6, or C3H8, (2) theoretical (quasiclassical trajectory) studies of hot hydrogen atom collision dynamics, (3) the development of photochemical sources of translationally hot molecular free radicals and characterization of the high resolution CARS spectroscopy of molecular free radicals, (4) the implementation of stimulated Raman excitation (SRE) techniques for the preparation of vibrationally state-selected molecular reactants

  9. EFFECT OF A HIGH-ENERGY DIET AND CHEMICAL COMPOUNDS ON THE DEVELOPMENT OF OBEITY

    Directory of Open Access Journals (Sweden)

    A.Djalayer

    1977-12-01

    Full Text Available The mechanism of the genesis and development of obesity is not yet known. In particular, it is not known whether the main reason is and increase in energetic efficiency, i.e. better utilization of food consumed, or hyperplasia. This study was undertaken to throw some light on this subject. Obesity was produced by chemical methods, i.e. by injections of gold-thioglucose and mono-sodium glutamate, as well as by feeding a high energy (high-fat-high-protein diet, in weanling, female mice. In these mice food intake, growth rate and body composition changes during growth were investigated. The results obtained show that increased energetic efficiency rather and hyperplasia plays the dominant role in the genesis and development of obesity. More research has to be carried out on this subject in man.

  10. Chemical Composition of the Essential Oil and Diethyl Ether Extract of Trinia glauca (L.) Dumort. (Apiaceae) and the Chemotaxonomic Significance of 5-O-Methylvisamminol.

    Science.gov (United States)

    Radulović, Niko S; Đorđević, Miljana R; Dekić, Milan S; Blagojević, Polina D

    2016-04-01

    Analyses by GC, GC/MS, and NMR spectroscopy (1D- and 2D-experiments) of the essential oil and Et2 O extract of Trinia glauca (L.) Dumort. (Apiaceae) aerial parts allowed a successful identification of 220 constituents, in total. The major identified compounds of the essential oil were (Z)-falcarinol (10.6%), bicyclogermacrene (8.0%), germacrene D (7.4%), δ-cadinene (4.3%), and β-caryophyllene (3.2%), whereas (Z)-falcarinol (47.2%), nonacosane (7.4%), and 5-O-methylvisamminol (4.0%) were the dominant constituents of the extract of T. glauca. One significant difference between the compositions of the herein and the previously analyzed T. glauca essential oils (only two reports) was noted. (Z)-Falcarinol was the major constituent in our case, whereas germacrene D (14.4 and 19.6%) was the major component of the previously studied oils. Possible explanations for this discrepancy were discussed. 5-O-Methylvisamminol, a (furo)chromone identified in the extract of T. glauca, has a limited occurrence in the plant kingdom and is a possible excellent chemotaxonomic marker (family and/or subfamily level) for Apiaceae. PMID:26919331

  11. PREDICTION OF CHEMICAL COMPOSITION AND ENERGY VALUE OF GRASS SILAGE BY NEAR-INFRARED REFLECTANCE SPECTROSCOPY

    Directory of Open Access Journals (Sweden)

    TOMAŽ ŽNIDARŠIČ

    2006-10-01

    Full Text Available One hundred and eighteen grass silage samples with known chemical composition and in vitro determined concentration of net energy for lactation (NEL were scanned over the wavelength range from 1100 to 2500 nm at 8 nm intervals. Calibration equations for the prediction of crude protein (CP, crude fi bre (CF, crude fat (F, crude ash (A, dry matter of air-dried samples (DM and NEL were developed by the use of principal component analysis (PCA and modifi ed partial least squares regression technique (mPLS. NIRS demonstrated high predictive ability for CP (R2 = 0.97, CF (R2 = 0.96 and A (R2 = 0.94. Moderate accuracy was characteristic for F and DM (R2 = 0.81 and 0.79. Crude protein, F and DM deviations from reference methods were comparable to those which are expected by the use of the same reference methods in different laboratories. The determination coeffi cient for in vitro assessed NEL concentration was 0.76. Seventy-seven percent of samples lied within acceptable limits of ± 0.3 MJ NEL kg-1DM. Suboptimal sample distribution, i.e. small number of samples in classes below 4.6 and above 6.0 MJ NEL kg-1DM was observed. It seems that deviations of NIRS predicted values from the reference values were related to the concentration of NEL. It was concluded that NIRS shows the potential for reliable determination of chemical composition and energy value of grass silage.

  12. Kirkwood-Buff Integrals for Aqueous Urea Solutions Based upon the Quantum Chemical Electrostatic Potential and Interaction Energies.

    Science.gov (United States)

    Chiba, Shuntaro; Furuta, Tadaomi; Shimizu, Seishi

    2016-08-11

    Cosolvents, such as urea, affect protein folding and binding, and the solubility of solutes. The modeling of cosolvents has been facilitated significantly by the rigorous Kirkwood-Buff (KB) theory of solutions, which can describe structural thermodynamics over the entire composition range of aqueous cosolvent mixtures based only on the solution density and the KB integrals (KBIs), i.e., the net excess radial distribution functions from the bulk. Using KBIs to describe solution thermodynamics has given rise to a clear guideline that an accurate prediction of KBIs is equivalent to accurate modeling of cosolvents. Taking urea as an example, here we demonstrate that an improvement in the prediction of KBIs comes from an improved reproduction of high-level quantum chemical (QC) electrostatic potential and molecular pairwise interaction energies. This rational approach to the improvement of the KBI prediction stems from a comparison of existing force fields, AMOEBA, and the generalized AMBER force field, as well as the further optimization of the former to enable better agreement with QC interaction energies. Such improvements would pave the way toward a rational and systematic determination of the transferable force field parameters for a number of important small molecule cosolvents. PMID:27434200

  13. Data-driven research on chemical features of Jingdezhen and Longquan celadon by energy dispersive X-ray fluorescence

    OpenAIRE

    He, Ziyang; Maolin ZHANG; Zhang, Haozhe

    2015-01-01

    The energy dispersive X-ray fluorescence (EDXRF) is used to determine the chemical composition of celadon body and glaze in Longquan kiln (at Dayao County) and Jingdezhen kiln. Forty typical shards in four cultural eras were selected to investigate the raw materials and firing technology. Random forests, a relatively new statistical technique, has been adopted to identify chemical elements that are strongest explanatory variables to classify samples into defferent cultural eras and kilns. The...

  14. Measurement of the chemical composition of the ultra-high-energy cosmic rays with the Pierre Auger Observatory

    CERN Document Server

    Plum, Matthias

    2013-01-01

    The Pierre Auger Observatory infers the chemical composition of ultra-high-energy cosmic rays through two independent detection techniques. The Fluorescence Detector (FD) measures the longitudinal profile of high energy air showers and can determine the depth of the shower maximum $X_{max}$, which is sensitive to the chemical composition of the primary cosmic rays. Additionally, measurements by the Surface Detector (SD) provide independent experimental observables based on the muonic shower component to analyze the chemical composition. We present the results for the $X_{max}$ distributions and the mass composition results measured by the FD and the SD for the energies $E \\geq 10^{18}$\\,eV. The data will be compared with the expectations for proton and iron primaries according to different hadronic interaction models.

  15. Quantum chemical calculations of bond dissociation energies for COOH scission and electronic structure in some acids

    Institute of Scientific and Technical Information of China (English)

    Zeng Hui; Zhao Jun; Xiao Xun

    2013-01-01

    Quantum chemical calculations are performed to investigate the equilibrium C-COOH bond distances and the bond dissociation energies (BDEs) for 15 acids.These compounds are studied by utilizing the hybrid density functional theory (DFT) (B3LYP,B3PW91,B3P86,PBE1PBE) and the complete basis set (CBS-Q) method in conjunction with the 6-31 lG** basis as DFT methods have been found to have low basis sets sensitivity for small and medium molecules in our previous work.Comparisons between the computational results and the experimental values reveal that CBS-Q method,which can produce reasonable BDEs for some systems in our previous work,seems unable to predict accurate BDEs here.However,the B3P86 calculated results accord very well with the experimental values,within an average absolute error of 2.3 kcal/mol.Thus,B3P86 method is suitable for computing the reliable BDEs of C-COOH bond for carboxylic acid compounds.In addition,the energy gaps between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of studied compounds are estimated,based on which the relative thermal stabilities of the studied acids are also discussed.

  16. Quantum chemical calculations of bond dissociation energies for COOH scission and electronic structure in some acids

    International Nuclear Information System (INIS)

    Quantum chemical calculations are performed to investigate the equilibrium C—COOH bond distances and the bond dissociation energies (BDEs) for 15 acids. These compounds are studied by utilizing the hybrid density functional theory (DFT) (B3LYP, B3PW91, B3P86, PBE1PBE) and the complete basis set (CBS—Q) method in conjunction with the 6-311G** basis as DFT methods have been found to have low basis sets sensitivity for small and medium molecules in our previous work. Comparisons between the computational results and the experimental values reveal that CBS—Q method, which can produce reasonable BDEs for some systems in our previous work, seems unable to predict accurate BDEs here. However, the B3P86 calculated results accord very well with the experimental values, within an average absolute error of 2.3 kcal/mol. Thus, B3P86 method is suitable for computing the reliable BDEs of C—COOH bond for carboxylic acid compounds. In addition, the energy gaps between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of studied compounds are estimated, based on which the relative thermal stabilities of the studied acids are also discussed. (atomic and molecular physics)

  17. Problems of the chemical and energy utilization of hydrocarbon raw materials of Siberia

    Energy Technology Data Exchange (ETDEWEB)

    Kalechits, I.V.

    1981-01-01

    According to forcasts, in the year 2000 the chemical industry (not including the Socialists coutries) will use 17% of all of the petroleum consumed, and in the year 2020 it will use 50%. A comprehensive integrated program is given here for developing processes and equipment to produce synthetic liquid and gaseous hydrocarbons from coal and other types of raw materials. During the 1980's different technological solutions in this field must be checked out at large commercial testing facilities, a technical and economic basis must be developed for constructing the first commercial undertaking, and its construction must start during the twelfth five-year plan. Moreover, the integrated target program should include a determination of the most economical method of transporting cheap Siberian energy to the European section of the USSR. Various ways of transmitting synthetic petroleum-enriched coal or electrical energy which is transmitted along superconducting transmission lines are examined. It is anticipated that during the eleventh five-year plan the petroleum utilization will not be advantageous in comparison with coal. Another important problem of the integrated target program is to reduce the consuption of fuel by increasing the selectivity of catalysts and reducing the operating temperature of process which will allow one to save tens of millions of tons of petroleum every year. Commercial petroleum plants are being constructed in Siberia which are designed to use the new catalysts, i.e. they will be more economical.

  18. Effect of biomass feedstock chemical and physical properties on energy conversion processes: Volume 2, Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Butner, R.S.; Elliott, D.C.; Sealock, L.J., Jr.; Pyne, J.W.

    1988-12-01

    This report presents an exploration of the relationships between biomass feedstocks and the conversion processes that utilize them. Specifically, it discusses the effect of the physical and chemical structure of biomass on conversion yields, rates, and efficiencies in a wide variety of available or experimental conversion processes. A greater understanding of the complex relationships between these conversion systems and the production of biomass for energy uses is required to help optimize the complex network of biomass production, collection, transportation, and conversion to useful energy products. The review of the literature confirmed the scarcity of research aimed specifically at identifying the effect of feedstock properties on conversion. In most cases, any mention of feedstock-related effects was limited to a few brief remarks (usually in qualitative terms) in the conclusions, or as a topic for further research. Attempts to determine the importance of feedstock parameters from published data were further hampered by the lack of consistent feedstock characterization and the difficulty of comparing results between different experimental systems. Further research will be required to establish quantitative relationships between feedstocks and performance criteria in conversion. 127 refs., 4 figs., 7 tabs.

  19. On the use of chemical reaction rates with discrete internal energies in the direct simulation Monte Carlo method

    Science.gov (United States)

    Gimelshein, S. F.; Gimelshein, N. E.; Levin, D. A.; Ivanov, M. S.; Wysong, I. J.

    2004-07-01

    The conventional chemical reaction models of the direct simulation Monte Carlo method developed with the assumption of continuous rotational or vibrational modes that are shown to exhibit systematic errors when used with discrete energy modes. A reaction model is proposed that is consistent with the use of discrete energy distributions of rotational and vibrational modes, and is equally applicable to diatomic and polyatomic systems. The sensitivity of the model to variations of different reaction rate parameters is examined. The revised chemical reaction model is then applied to the modeling of hypersonic flows over spacecraft in the Martian and Earth atmospheres.

  20. Effect of dry oxidation on the energy gap and chemical composition of CVD graphene on nickel

    International Nuclear Information System (INIS)

    The findings presented herein show that the electronic properties of CVD graphene on nickel can be altered from metallic to semiconducting by introducing oxygen adsorbates via UV/ozone or oxygen plasma treatment. These properties can be partially recovered by removing the oxygen adsorbates via vacuum annealing treatment. The effect of oxidation is studied by scanning tunneling microscopy/spectroscopy (STM/STS) and X-ray photoelectron spectroscopy (XPS). As probed by STM/STS, an energy gap opening of 0.11–0.15 eV is obtainable as the oxygen/carbon atomic ratio reaches 13–16%. The corresponding XPS spectra show a significant monotonic increase in the concentration of oxygenated functional groups due to the oxidation treatments. This study demonstrates that the opening of energy gap in CVD graphene can be reasonably controlled by a combination of UV/ozone or oxygen plasma treatment and vacuum annealing treatment.

  1. Influence of chemical disorder on energy dissipation and defect evolution in concentrated solid solution alloys

    International Nuclear Information System (INIS)

    A long-standing objective in materials research is to understand how energy is dissipated in both the electronic and atomic subsystems in irradiated materials, and how related non-equilibrium processes may affect defect dynamics and microstructure evolution. Here we show that alloy complexity in concentrated solid solution alloys having both an increasing number of principal elements and altered concentrations of specific elements can lead to substantial reduction in the electron mean free path and thermal conductivity, which has a significant impact on energy dissipation and consequentially on defect evolution during ion irradiation. Enhanced radiation resistance with increasing complexity from pure nickel to binary and to more complex quaternary solid solutions is observed under ion irradiation up to an average damage level of 1 displacement per atom. Understanding how materials properties can be tailored by alloy complexity and their influence on defect dynamics may pave the way for new principles for the design of radiation tolerant structural alloys

  2. Effect of dry oxidation on the energy gap and chemical composition of CVD graphene on nickel

    Energy Technology Data Exchange (ETDEWEB)

    Aria, Adrianus I. [Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125 (United States); Gani, Adi W. [Department of Electrical Engineering, California Institute of Technology, Pasadena, CA 91125 (United States); Gharib, Morteza, E-mail: mgharib@caltech.edu [Graduate Aeronautical Laboratories, California Institute of Technology, Pasadena, CA 91125 (United States)

    2014-02-28

    The findings presented herein show that the electronic properties of CVD graphene on nickel can be altered from metallic to semiconducting by introducing oxygen adsorbates via UV/ozone or oxygen plasma treatment. These properties can be partially recovered by removing the oxygen adsorbates via vacuum annealing treatment. The effect of oxidation is studied by scanning tunneling microscopy/spectroscopy (STM/STS) and X-ray photoelectron spectroscopy (XPS). As probed by STM/STS, an energy gap opening of 0.11–0.15 eV is obtainable as the oxygen/carbon atomic ratio reaches 13–16%. The corresponding XPS spectra show a significant monotonic increase in the concentration of oxygenated functional groups due to the oxidation treatments. This study demonstrates that the opening of energy gap in CVD graphene can be reasonably controlled by a combination of UV/ozone or oxygen plasma treatment and vacuum annealing treatment.

  3. Effect of dry oxidation on the energy gap and chemical composition of CVD graphene on nickel

    Science.gov (United States)

    Aria, Adrianus I.; Gani, Adi W.; Gharib, Morteza

    2014-02-01

    The findings presented herein show that the electronic properties of CVD graphene on nickel can be altered from metallic to semiconducting by introducing oxygen adsorbates via UV/ozone or oxygen plasma treatment. These properties can be partially recovered by removing the oxygen adsorbates via vacuum annealing treatment. The effect of oxidation is studied by scanning tunneling microscopy/spectroscopy (STM/STS) and X-ray photoelectron spectroscopy (XPS). As probed by STM/STS, an energy gap opening of 0.11-0.15 eV is obtainable as the oxygen/carbon atomic ratio reaches 13-16%. The corresponding XPS spectra show a significant monotonic increase in the concentration of oxygenated functional groups due to the oxidation treatments. This study demonstrates that the opening of energy gap in CVD graphene can be reasonably controlled by a combination of UV/ozone or oxygen plasma treatment and vacuum annealing treatment.

  4. Chemical, dimensional and morphological ultrafine particle characterization from a waste-to-energy plant

    International Nuclear Information System (INIS)

    Highlights: → Particle size distributions and total concentrations measurement at the stack and before the fabric filter of an incinerator. → Chemical characterization of UFPs in terms of heavy metal concentration through a nuclear method. → Mineralogical investigation through a Transmission Electron Microscope equipped with an Energy Dispersive Spectrometer. → Heavy metal concentrations on UFPs as function of the boiling temperature. → Different mineralogical and morphological composition amongst samples collected before the fabric filter and at the stack. - Abstract: Waste combustion processes are responsible of particles and gaseous emissions. Referring to the particle emission, in the last years specific attention was paid to ultrafine particles (UFPs, diameter less than 0.1 μm), mainly emitted by combustion processes. In fact, recent findings of toxicological and epidemiological studies indicate that fine and ultrafine particles could represent a risk for health and environment. Therefore, it is necessary to quantify particle emissions from incinerators also to perform an exposure assessment for the human populations living in their surrounding areas. To these purposes, in the present work an experimental campaign aimed to monitor UFPs was carried out at the incineration plant in San Vittore del Lazio (Italy). Particle size distributions and total concentrations were measured both at the stack and before the fabric filter inlet in order to evaluate the removal efficiency of the filter in terms of UFPs. A chemical characterization of UFPs in terms of heavy metal concentration was performed through a nuclear method, i.e. Instrumental Neutron Activation Analysis (INAA), as well as a mineralogical investigation was carried out through a Transmission Electron Microscope (TEM) equipped with an Energy Dispersive Spectrometer (EDS) in order to evaluate shape, crystalline state and mineral compound of sampled particles. Maximum values of 2.7 x 107 part. cm-3

  5. A quantum chemical study from a molecular perspective: ionization and electron attachment energies for species often used to fabricate single-molecule junctions

    CERN Document Server

    Baldea, Ioan

    2015-01-01

    The accurate determination of the lowest electron attachment ($EA$) and ionization ($IP$) energies for molecules embedded in molecular junctions is important for correctly estimating, \\emph{e.g.}, the magnitude of the currents ($I$) or the biases ($V$) where an $I-V$-curve exhibits a significant non-Ohmic behavior. Benchmark calculations for the lowest electron attachment and ionization energies of several typical molecules utilized to fabricate single-molecule junctions characterized by n-type conduction (4,4'-bipyridine, 1,4-dicyanobenzene, and 4,4'-dicyano-1,1'-biphenyl) and p-type conduction (benzenedithiol, biphenyldithiol, hexanemonothiol, and hexanedithiol] based on the EOM-CCSD (equation-of-motion coupled-cluster singles and doubles) state-of-the-art method of quantum chemistry are presented. They indicate significant differences from the results obtained within current approaches to molecular transport. The present study emphasizes that, in addition to a reliable quantum chemical method, basis sets m...

  6. Bio-based targeted chemical engineering education : Role and impact of bio-based energy and resourcedevelopment projects

    NARCIS (Netherlands)

    Márquez Luzardoa, N.M.; Venselaar, Jan

    2012-01-01

    Avans University of Applied Sciences is redrafting its courses and curricula in view of sustainability. For chemical engineering in particular that implies a focus on 'green' and bio-based processes, products and energy. Avans is situated in the Southwest region of the Netherlands and specifically i

  7. Clinical evaluation of the cerebral energy metabolism with 31P chemical shift imaging in neurosurgical disorders

    International Nuclear Information System (INIS)

    Cerebral energy metabolism was evaluated by means of 31P chemical shift imaging (CSI) using the 2.0 T whole-body MRIS system. 31P CSI was carried out by means of Spectroscopic Imaging by Dephasing Amplitude Changing method, four-dimensional CSI, and three-dimensional CSI. Twenty three patients with cerebral infarction and 21 patients with hypertensive intracerebral hemorrhage were examined. In cerebral infarction, an acute infarction was seen as a low-signal area in the PCr and ATP images and as a high-signal area in the Pi image. A subacute and chronic infarction was seen as a low-signal area in all the images -- 31P, PCr, ATP, Pi, PDE and PME. Intracellular acidosis was noticed within 2 days after onset. The intracellular pH became alkaline at the subacute and chronic stages of infarction. The chronological changes in the phosphorus metabolites were evaluated by means of these methods. In hypertensive intracerebral hemorrhage, hematoma and perifocal edema in the acute stage were seen as low-signal areas in the 31P, PCr, and ATP images, and as high-signal areas in the Pi image. In the chronic stage, a hematoma was seen as a low-signal area in all the images -- 31P, PCr, ATP and Pi. 31P CSI is thus a practical tool for studying phosphate metabolites clinically. Changes in the phosphorus metabolism relative to the anatomy of interest were detected by the use of these methods. (author)

  8. Production and distribution of domestic hot water in selected Danish apartment buildings and institutions. Analysis of consumption, energy efficiency and the significance for energy design requirements of buildings

    International Nuclear Information System (INIS)

    Highlights: ► Circulation system heat losses were 23–70% in apartment buildings. ► The use of additional heat meters in large buildings is recommended. ► The demand for domestic hot water, space heating and ventilation should be obtained. ► Domestic hot water will constitute a major part of future energy demand of dwellings. - Abstract: The goal of this work has been to document the efficiency of domestic hot water (DHW) distribution systems and to propose more energy efficient and environmentally friendly solutions for DHW systems based on analyses of existing conditions. In the article, measurements from 13 apartment buildings and two institutions are presented, i.e. consumption of DHW, heat loss from circulation lines and efficiency of the DHW system. The heat load and the cooling of the district heating water for DHW are documented as well. Possibilities for improving the DHW system include new types of circulation pipes, which have the potential of a 40% reduction of heat losses. In addition to the reduction of heat losses inside the building, a low return temperature from the hot water system will have a large impact on the heat losses from the district heating network when the building is being heated by district heating. It is likely that the production and distribution of DHW in buildings will constitute a dominant share of both the present, and in particular, the future energy design requirements of buildings. The results of this project could influence not only future buildings, but also existing buildings when renovation of installations take place

  9. Optical and chemical behaviors of CR-39 and Makrofol plastics under low-energy electron beam irradiation

    Science.gov (United States)

    El-Saftawy, Ashraf Ali; Abd El Aal, Saad Ahmed; Hassan, Nabil Mohamed; Abdelrahman, Moustafa Mohamed

    2016-07-01

    In this study, CR-39 and Makrofol plastic nuclear track detectors were irradiated with low-energy electron beams to study the effect of the induced changes on their optical and chemical properties. Surface chemical changes were recorded by Fourier transform infrared (FTIR) spectroscopy, which showed successive degradation and crosslinking for CR-39 and decomposition for Makrofol. The optical band gap was determined by UV–vis spectroscopy. Also, the parameters of carbon cluster formation and disordering (Urbach’s energy) occurring on plastic surfaces were examined. The intrinsic viscosity changes were investigated as well. As a result, low-energy electron beams were found to be useful for the control of many properties of the surfaces of the investigated detectors.

  10. Optimizing the Binding Energy of Hydrogen on Nanostructured Carbon Materials through Structure Control and Chemical Doping

    Energy Technology Data Exchange (ETDEWEB)

    Jie Liu

    2011-02-01

    The DOE Hydrogen Sorption Center of Excellence (HSCoE) was formed in 2005 to develop materials for hydrogen storage systems to be used in light-duty vehicles. The HSCoE and two related centers of excellence were created as follow-on activities to the DOE Office of Energy Efficiency and Renewable Energy’s (EERE’s) Hydrogen Storage Grand Challenge Solicitation issued in FY 2003. The Hydrogen Sorption Center of Excellence (HSCoE) focuses on developing high-capacity sorbents with the goal to operate at temperatures and pressures approaching ambient and be efficiently and quickly charged in the tank with minimal energy requirements and penalties to the hydrogen fuel infrastructure. The work was directed at overcoming barriers to achieving DOE system goals and identifying pathways to meet the hydrogen storage system targets. To ensure that the development activities were performed as efficiently as possible, the HSCoE formed complementary, focused development clusters based on the following four sorption-based hydrogen storage mechanisms: 1. Physisorption on high specific surface area and nominally single element materials 2. Enhanced H2 binding in Substituted/heterogeneous materials 3. Strong and/or multiple H2 binding from coordinated but electronically unsatruated metal centers 4. Weak Chemisorption/Spillover. As a member of the team, our group at Duke studied the synthesis of various carbon-based materials, including carbon nanotubes and microporous carbon materials with controlled porosity. We worked closely with other team members to study the effect of pore size on the binding energy of hydrogen to the carbon –based materials. Our initial project focus was on the synthesis and purification of small diameter, single-walled carbon nanotubes (SWNTs) with well-controlled diameters for the study of their hydrogen storage properties as a function of diameters. We developed a chemical vapor deposition method that synthesized gram quantities of carbon nanotubes with

  11. Low bone mineral density is a significant risk factor for low-energy distal radius fractures in middle-aged and elderly men: A case-control study

    Directory of Open Access Journals (Sweden)

    Johnsen Villy

    2011-04-01

    Full Text Available Abstract Background In general there is a lack of data on osteoporosis and fracture in men; this also includes low-energy distal radius fractures. The objectives of this study were to examine BMD and identify factors associated with distal radius fractures in male patients compared with controls recruited from the background population. Methods In a 2-year period, 44 men 50 years or older were diagnosed with low-energy distal radius fractures, all recruited from one hospital. The 31 men who attended for osteoporosis assessment were age-matched with 35 controls. Demographic and clinical data were collected and BMD at femoral neck, total hip and spine L2-4 was assessed by dual energy X-ray absorptiometry. Results Apart from weight and living alone, no significant differences were found between patient and controls for demographic variables (e.g. height, smoking and clinical variables (e.g. co-morbidity, use of glucocorticoids, osteoporosis treatment, falls and previous history of fracture. However, BMD expressed as T-score was significant lower in patients than in controls at all measurement sites (femoral neck: -2.24 vs. -1.15, p Conclusion The results from our study indicate that reduced BMD is an important risk factor for low-energy distal radius fracture in men. This suggests that improvement of BMD by both pharmacological and non-pharmacological initiatives may be a strategy to reduce fracture risk in men.

  12. Chemical composition, morphology and optical properties of zinc sulfide coatings deposited by low-energy electron beam evaporation

    International Nuclear Information System (INIS)

    The research determines the features of formation, morphology, chemical composition and optical properties of the coatings deposited by the method, proposed for the first time, of the exposure of mechanical mixture of zinc and sulfur powders to low-energy electron beam evaporation. The findings show that the deposited coatings are characterized by high chemical and structural homogeneity in thickness. The study considers the influence of substrate temperature and thickness of the deposited layer on the morphology and the width of the formed ZnS thin layers band gap. Also was shown the possibility to form ZnS coatings with this method using the mixture of zinc and copper sulfide powders.

  13. Chemical composition, morphology and optical properties of zinc sulfide coatings deposited by low-energy electron beam evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Ragachev, A.V. [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Yarmolenko, M.A., E-mail: simmak79@mail.ru [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Rogachev, A.A. [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China); Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Gorbachev, D.L. [Francisk Skorina Gomel State University, 104, Sovetskaya Street, Gomel 246019 (Belarus); Zhou, Bing [International Chinese-Belorussian scientific laboratory on vacuum-plasma technology, College of Chemical Engineering, Nanjing University of Science and Technology, Nanjing 210094 (China)

    2014-06-01

    The research determines the features of formation, morphology, chemical composition and optical properties of the coatings deposited by the method, proposed for the first time, of the exposure of mechanical mixture of zinc and sulfur powders to low-energy electron beam evaporation. The findings show that the deposited coatings are characterized by high chemical and structural homogeneity in thickness. The study considers the influence of substrate temperature and thickness of the deposited layer on the morphology and the width of the formed ZnS thin layers band gap. Also was shown the possibility to form ZnS coatings with this method using the mixture of zinc and copper sulfide powders.

  14. An approach to the determination of physical-chemical limits of energy consumption for the transition to a stationary state

    International Nuclear Information System (INIS)

    The paper gives a model of energy consumption and a programme for its application. Previous models are mainly criticized on the grounds that new technological developments as well as adjustments due to learning processes of homo sapiens are generally not sufficiently accounted for in these models. The approach of this new model is therefore an attempt at the determination of the physical-chemical limiting values for the capacity of the global HST (homo sapiens - Tellus) system or of individual regions with respect to certain critical factors. These limiting values determined by the physical-chemical system of the earth are independent of human ingenuity and flexibility. (orig./AK)

  15. Chemical gas sensors and the characterization, monitoring and sensor technology needs of the US Department of Energy

    International Nuclear Information System (INIS)

    The Office of Technology Development within the Dept. of Energy (DOE) has the responsibility of providing new technologies to aid the environmental restoration and waste management (ER/WM) activities of the DOE. There is a perception that application and judicious development of chemical sensor technologies could result in large cost savings and reduced risk to the health and safety of ER/WM personnel. A number of potential gas sensor applications which exist within DOE ER/WM operations are described. The capabilities of several chemical sensor technologies and their potential to meet the needs of ER/WM applications in the present or near term future are discussed

  16. Mass, energy, and exergy balance analysis of chemical looping with oxygen uncoupling (CLOU) process

    International Nuclear Information System (INIS)

    Highlights: • A CLOU reactor system using a CuO-based OC and coal as fuel is analyzed. • Possible operational regions for the chosen OC are identified. • Different heat balance scenarios are investigated. • The second-law efficiency of the system is evaluated. • Various design aspects and process modelling relationships are discussed. - Abstract: Chemical looping with oxygen uncoupling (CLOU) is a promising concept for efficient combustion of solid fuels with an inherent capture of the greenhouse gas CO2. This paper presents a CLOU process scheme with stoichiometric mass, energy, and exergy balances. A CLOU reactor system using medium volatile bituminous coal as fuel and silica-supported CuO as an oxygen carrier is analyzed. The analysis includes the estimation of various design and operational parameters, thermal considerations, and evaluation of the overall performance. The operation of a reactor system of two interacting circulating fluidized beds (CFBs) is greatly influenced by the hydrodynamics. For the CuO oxygen carrier, the hydrodynamic operating range appeared feasible considering the maximum solid circulation rates in current CFB boilers. Depending upon the reactor temperatures, oxygen carrier inventories of 400–680 kg/MW in the system were found necessary for stoichiometric combustion of the fuel. The temperature difference between the reactors should not exceed 50 °C, as otherwise, problems may arise with the heat balance. Exergetic efficiencies in the range of 63–70% were obtained for different combinations of relevant design parameters. It is evident that the possible operating conditions in the system are closely related to the properties of the chosen oxygen carrier. However, the calculation procedure and design criteria presented here are applicable to any oxygen carrier to be used in the process

  17. Chemicals-Industry of the Future; Industrial Partnerships: Advancing Energy and Environmental Goals

    International Nuclear Information System (INIS)

    This tri-fold brochure describe the partnering activities of the Office of Industrial Technologies' (OIT) Industries of the Future (IOF) for Chemicals. Information on what works for the Chemicals industry, examples of successful partnerships, and benefits of partnering with OIT are included

  18. Energy consumption analysis of Spanish food and drink, textile, chemical and non-metallic mineral products sectors

    International Nuclear Information System (INIS)

    This paper provides quantitative information for energy consumption from four different industry sectors based on an energy analysis obtained by means of in-situ energy audits and complementary information. The latter information was taken from Saving Strategy and Energy Efficiency in Spain (Estrategia de Ahorro y Eficiencia Energética en España 2004–2010, E4) documents and the 2009 Industrial Survey of Spain from the National Statistics Institute (Instituto Nacional de Estadística, INE). The results show an estimate of energy consumption for each sector, namely Spanish food, drink and tobacco (9.6%), textile (4.5%), chemical (14.7%), and non-metallic mineral products (24.3%), as well as the degree of inefficiency for each, obtained by means of a stochastic frontier production function model. These results are combined with the energy consumption analysis to identify potential energy saving opportunities around 20.0% of the total energy consumption for all studied sectors. These energy saving opportunities are classified according to thermal or electrical energy consumption and percentage savings of the total energy consumption. -- Highlights: ► This study presents the analysis of four Spanish energy-consuming industrial sectors. ► The four selected sectors account for 33.0% of the total industrial SMEs. ► An audit was carried out in several factories from each analysed industrial sector. ► Stochastic Cobb-Douglas frontiers were used to estimate production frontiers. ► Potential energy saving opportunities around 20.0% of the total energy consumption.

  19. The Carbon and Global Warming Potential Impacts of Organic Farming: Does It Have a Significant Role in an Energy Constrained World?

    Directory of Open Access Journals (Sweden)

    Ralph C. Martin

    2011-01-01

    Full Text Available About 130 studies were analyzed to compare farm-level energy use and global warming potential (GWP of organic and conventional production sectors. Cross cutting issues such as tillage, compost, soil carbon sequestration and energy offsets were also reviewed. Finally, we contrasted E and GWP data from the wider food system. We concluded that the evidence strongly favours organic farming with respect to whole-farm energy use and energy efficiency both on a per hectare and per farm product basis, with the possible exception of poultry and fruit sectors. For GWP, evidence is insufficient except in a few sectors, with results per ha more consistently favouring organic farming than GWP per unit product. Tillage was consistently a negligible contributor to farm E use and additional tillage on organic farms does not appear to significantly deplete soil C. Energy offsets, biogas, energy crops and residues have a more limited role on organic farms compared to conventional ones, because of the nutrient and soil building uses of soil organic matter, and the high demand for organic foods in human markets. If farm E use represents 35% of total food chain E use, improvements shown of 20% or more in E efficiency through organic farm management would reduce food-chain E use by 7% or more. Among other food supply chain stages, wholesale/retail (including cooling and packaging and processing often each contribute 30% or more to total food system E. Thus, additional improvements can be obtained with reduced processing, whole foods and food waste minimization.

  20. The metabolic cost of changing walking speeds is significant, implies lower optimal speeds for shorter distances, and increases daily energy estimates.

    Science.gov (United States)

    Seethapathi, Nidhi; Srinivasan, Manoj

    2015-09-01

    Humans do not generally walk at constant speed, except perhaps on a treadmill. Normal walking involves starting, stopping and changing speeds, in addition to roughly steady locomotion. Here, we measure the metabolic energy cost of walking when changing speed. Subjects (healthy adults) walked with oscillating speeds on a constant-speed treadmill, alternating between walking slower and faster than the treadmill belt, moving back and forth in the laboratory frame. The metabolic rate for oscillating-speed walking was significantly higher than that for constant-speed walking (6-20% cost increase for ±0.13-0.27 m s(-1) speed fluctuations). The metabolic rate increase was correlated with two models: a model based on kinetic energy fluctuations and an inverted pendulum walking model, optimized for oscillating-speed constraints. The cost of changing speeds may have behavioural implications: we predicted that the energy-optimal walking speed is lower for shorter distances. We measured preferred human walking speeds for different walking distances and found people preferred lower walking speeds for shorter distances as predicted. Further, analysing published daily walking-bout distributions, we estimate that the cost of changing speeds is 4-8% of daily walking energy budget. PMID:26382072

  1. Stepping stones to significant market shares for renewables. The European forum for market players and decision makers in the renewable energy industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This invitation to a two-day European Forum for market players and decision makers in the renewable energy business lists the presentations made at the conference in 2007. The programme included contributions in the following areas: Policies and market deployment initiatives, market trends and experience - from support schemes to market experience, opportunities in a changing framework in Switzerland, instruments and infrastructure requirements - how to make the market work and supply and demand aspects of a growing market. The conference examined how renewable forms of energy can gain significant market shares and reach a quota of 50% renewables in 50 years. The first session examined policies and market deployment initiatives, the second market trends and experiences, the third opportunities for Switzerland in a changing framework. The second day featured sessions on instruments and infrastructure requirements as well as on supply and demand aspects in a growing market. The conference was complemented with four workshops.

  2. Economic and safe operation of isolated systems with significant contribution from renewable energy sources; Operacao economica e segura de sistemas isolados com grande penetracao de energias renovaveis

    Energy Technology Data Exchange (ETDEWEB)

    Matos, M.A. [Instituto de Engenharia de Sistemas e Computadores (INESC), Porto (Portugal); Vlachos, A; Androutsos, A. [NTUA, Atenas (Greece); Bakirtzis, T. [AUTH, Salonica (Greece); Gigantidou, A. [DEI, Heraklio (Greece). E-mail: mmatos@inescn.pt; avlachos@power.ece.ntua.gr; bakiana@eng.auth.gr; deh_kkf@iraklio.netor.gr

    1999-07-01

    Medium and large size isolated systems with a significant contribution from renewable energy sources, specifically eolic energy, are not conveniently operated at the present, neither by the conventional ways of unit commitment/load dispatcher nor by the simplified procedures used in the small isolated power networks. This paper presents a new approaching, in the CARE framework which is financially supported by the European Union through the EEN-JOULE assistance program. The principal idea is to perform unit commitment on-line in the same dispatching cycle, by using the load forecasting and the more recent wind power. The process includes dynamic safety fast evaluation and a module for helping the decision making.

  3. Stepping stones to significant market shares for renewables. The European forum for market players and decision makers in the renewable energy industry

    International Nuclear Information System (INIS)

    This invitation to a two-day European Forum for market players and decision makers in the renewable energy business lists the presentations made at the conference in 2007. The programme included contributions in the following areas: Policies and market deployment initiatives, market trends and experience - from support schemes to market experience, opportunities in a changing framework in Switzerland, instruments and infrastructure requirements - how to make the market work and supply and demand aspects of a growing market. The conference examined how renewable forms of energy can gain significant market shares and reach a quota of 50% renewables in 50 years. The first session examined policies and market deployment initiatives, the second market trends and experiences, the third opportunities for Switzerland in a changing framework. The second day featured sessions on instruments and infrastructure requirements as well as on supply and demand aspects in a growing market. The conference was complemented with four workshops.

  4. Extension of the α particle energy range in polycarbonate using multiple step chemical and/or electrochemical etching

    International Nuclear Information System (INIS)

    For ten years polycarbonate has been widely used for the detection of α particles in radon dosimetry. Compared with CR-39 material, the detectable α energy range of about 0.5 to 3 MeV is, however, small after using a chemical pre-etching and electrochemical etching. In order to extend the α energy range the authors investigated: (a) a step-wise combination of chemical and ECE etching, and (b) a two-step ECE technique at low and high frequency. The results of this study show that α particle tracks can be revealed ranging from 0.5 to 5 MeV. For the two-step ECE technique a constant α registration efficiency has been found. (author)

  5. Chemical Potentials of Quarks Extracted from Particle Transverse Momentum Distributions in Heavy Ion Collisions at RHIC Energies

    Directory of Open Access Journals (Sweden)

    Hong Zhao

    2014-01-01

    Full Text Available In the framework of a multisource thermal model, the transverse momentum distributions of charged particles produced in nucleus-nucleus (A-A and deuteron-nucleus (d-A collisions at relativistic heavy ion collider (RHIC energies are investigated by a two-component revised Boltzmann distribution. The calculated results are in agreement with the PHENIX experimental data. It is found that the source temperature increases obviously with increase of the particle mass and incident energy, but it does not show an obvious change with the collision centrality. Then, the values of chemical potentials for up, down, and strange quarks can be obtained from the antiparticle to particle yield ratios in a wide transverse momentum range. The relationship between the chemical potentials of quarks and the transverse momentum with different centralities is investigated, too.

  6. Chemical Potentials of Quarks Extracted from Particle Transverse Momentum Distributions in Heavy Ion Collisions at RHIC Energies

    International Nuclear Information System (INIS)

    In the framework of a multisource thermal model, the transverse momentum distributions of charged particles produced in nucleus-nucleus (A-A) and deuteron-nucleus (d-A) collisions at relativistic heavy ion collider (RHIC) energies are investigated by a two-component revised Boltzmann distribution. The calculated results are in agreement with the PHENIX experimental data. It is found that the source temperature increases obviously with increase of the particle mass and incident energy, but it does not show an obvious change with the collision centrality. Then, the values of chemical potentials for up, down, and strange quarks can be obtained from the antiparticle to particle yield ratios in a wide transverse momentum range. The relationship between the chemical potentials of quarks and the transverse momentum with different centralities is investigated, too

  7. Huge Pressure from Energy Supply and Overheated Investment——analysis of China's Petrochemical and Chemical Industry

    Institute of Scientific and Technical Information of China (English)

    Feng Shiliang

    2007-01-01

    @@ The economic performance of China's petroleum and chemical industry is comprehensively decided by four major factors now: a. economy grows rapidly,boosting consumption demand; b. supply of energy and products consuming resources tends to be tighter; c. global crude oil price will continue to stay high,driving the production cost of its downstream products; d. the overly rapid increase of investment in fixed assets is difficult to control, so more and more products will face surplus production capacity.

  8. Conversion of bioprocess ethanol to industrial chemical products - Applications of process models for energy-economic assessments

    Science.gov (United States)

    Rohatgi, Naresh K.; Ingham, John D.

    1992-01-01

    An assessment approach for accurate evaluation of bioprocesses for large-scale production of industrial chemicals is presented. Detailed energy-economic assessments of a potential esterification process were performed, where ethanol vapor in the presence of water from a bioreactor is catalytically converted to ethyl acetate. Results show that such processes are likely to become more competitive as the cost of substrates decreases relative to petrolium costs. A commercial ASPEN process simulation provided a reasonably consistent comparison with energy economics calculated using JPL developed software. Detailed evaluations of the sensitivity of production cost to material costs and annual production rates are discussed.

  9. ESCA [electron spectroscopy for chemical analysis] examination of metal oxides and electronic ceramic materials: The effect of a low-energy argon-ion beam

    International Nuclear Information System (INIS)

    Electronic ceramic materials are increasingly of interest to chemists because there is a growing interest in preparing high purity ceramics by chemical means and because the properties of the ceramics often depend on the chemical state of the elements in the ceramic. The chemical species, e.g. the oxidation state, of a metal in a ceramic can be identified by the analytical technique known as ESCA (electron spectroscopy for chemical analysis). In this work, the application of ESCA to ceramic materials begins with studies of metal oxide powders and examines the effect of a low energy argon ion beam. Two problems that occur with oxide powders and ceramics are surface charging and the formation of carbonates on the surface. Surface charging is generally compensated for by referencing to the carbon contaminant or by flooding the surface with electrons. Referencing to the contaminant peak meets with limited success when compared to the literature. Flooding the surface of oxide powders and ceramics causes peak distortion. Surface carbonates are identified in the carbon region by their separation of -4.5 eV from the contaminant carbon. To examine the effect of a low energy ion beam on metal oxide powders and ceramic powders, both the X-ray photoelectron (XPS) and X-ray induced Auger electron spectra (XAES) of SC2O3, V2O5, Cu2 O, ZnO and SnO2 are examined before and after ion beam exposure. Limited reduction of the metal is noted in the XPS spectra of V2O5. XAES indicates the Sc2O3, Cu2O and SnO2 are also reduced. XAES is especially useful for determining that reduction by the ion beam has occurred. A comparison of ion beam exposed oxide powders and heavily oxidized metal foils (Ti, Zr and Nb) shows that while the powders undergo limited reduction, the oxidized foils are reduced much more significantly with the same sputtering parameters

  10. Energy

    CERN Document Server

    Foland, Andrew Dean

    2007-01-01

    Energy is the central concept of physics. Unable to be created or destroyed but transformable from one form to another, energy ultimately determines what is and isn''t possible in our universe. This book gives readers an appreciation for the limits of energy and the quantities of energy in the world around them. This fascinating book explores the major forms of energy: kinetic, potential, electrical, chemical, thermal, and nuclear.

  11. Significant improvements of the high-field properties of carbon-doped MgB2 films by hot-filament-assisted hybrid physical-chemical vapor deposition using methane as the doping source

    International Nuclear Information System (INIS)

    We report a significant enhancement in upper critical field Hc2 and irreversibility field Hirr in carbon-doped MgB2 films fabricated by hot-filament-assisted hybrid physical-chemical vapor deposition (HFA-HPCVD) using methane as the doping source. For the parallel field, a very large temperature derivative -dHc2parallelab/dT value of 3 T K-1 near Tc was achieved in a heavily doped film with Tc near 28 K. Carbon doping also enhanced flux pinning, resulting in a much higher critical current density in a magnetic field Jc(H) than in undoped samples. The result suggests a more effective doping of carbon into the MgB2 structure and a better connectivity between the carbon-doped MgB2 grains than in previous reports. A clear correlation between the decrease in grain size and the enhancement of Hc2 was observed. (rapid communication)

  12. Structure and function of natural sulphide-oxidizing microbial mats under dynamic input of light and chemical energy.

    Science.gov (United States)

    Klatt, Judith M; Meyer, Steffi; Häusler, Stefan; Macalady, Jennifer L; de Beer, Dirk; Polerecky, Lubos

    2016-04-01

    We studied the interaction between phototrophic and chemolithoautotrophic sulphide-oxidizing microorganisms in natural microbial mats forming in sulphidic streams. The structure of these mats varied between two end-members: one characterized by a layer dominated by large sulphur-oxidizing bacteria (SOB; mostly Beggiatoa-like) on top of a cyanobacterial layer (B/C mats) and the other with an inverted structure (C/B mats). C/B mats formed where the availability of oxygen from the water column was limited (45 μM) and continuously present. Here SOB were independent of the photosynthetic activity of cyanobacteria and outcompeted the cyanobacteria in the uppermost layer of the mat where energy sources for both functional groups were concentrated. Outcompetition of photosynthetic microbes in the presence of light was facilitated by the decoupling of aerobic chemolithotrophy and oxygenic phototrophy. Remarkably, the B/C mats conserved much less energy than the C/B mats, although similar amounts of light and chemical energy were available. Thus ecosystems do not necessarily develop towards optimal energy usage. Our data suggest that, when two independent sources of energy are available, the structure and activity of microbial communities is primarily determined by the continuous rather than the intermittent energy source, even if the time-integrated energy flux of the intermittent energy source is greater. PMID:26405833

  13. Energy production and storage inorganic chemical strategies for a warming world

    CERN Document Server

    Crabtree, Robert H

    2013-01-01

    Energy production and storage are central problems for our time. In principle, abundant energy is available from the sun to run the earth in a sustainable way. Solar energy can be directly harnessed by agricultural and photovoltaic means, but the sheer scale of the energy demand poses severe challenges, for example any major competition between biomass production and food production would simply transfer scarcity from energy to food. Indirect use of solar energy in the form of wind looks also promising, especially for those regions not blessed with abundant sunlight. Other modes such as tidal

  14. Global challenges and strategies for control, conversion and utilization of CO{sub 2} for sustainable development involving energy, catalysis, adsorption and chemical processing

    Energy Technology Data Exchange (ETDEWEB)

    Song, Chunshan [Clean Fuels and Catalysis Program, The Energy Institute, and Department of Energy and Geo-Environmental Engineering, The Pennsylvania State University 209 Academic Projects Building, University Park, PA 16802 (United States)

    2006-06-30

    Utilization of carbon dioxide (CO{sub 2}) has become an important global issue due to the significant and continuous rise in atmospheric CO{sub 2} concentrations, accelerated growth in the consumption of carbon-based energy worldwide, depletion of carbon-based energy resources, and low efficiency in current energy systems. The barriers for CO{sub 2} utilization include: (1) costs of CO{sub 2} capture, separation, purification, and transportation to user site; (2) energy requirements of CO{sub 2} chemical conversion (plus source and cost of co-reactants); (3) market size limitations, little investment-incentives and lack of industrial commitments for enhancing CO{sub 2}-based chemicals; and (4) the lack of socio-economical driving forces. The strategic objectives may include: (1) use CO{sub 2} for environmentally-benign physical and chemical processing that adds value to the process; (2) use CO{sub 2} to produce industrially useful chemicals and materials that adds value to the products; (3) use CO{sub 2} as a beneficial fluid for processing or as a medium for energy recovery and emission reduction; and (4) use CO{sub 2} recycling involving renewable sources of energy to conserve carbon resources for sustainable development. The approaches for enhancing CO{sub 2} utilization may include one or more of the following: (1) for applications that do not require pure CO{sub 2}, develop effective processes for using the CO{sub 2}-concentrated flue gas from industrial plants or CO{sub 2}-rich resources without CO{sub 2} separation; (2) for applications that need pure CO{sub 2}, develop more efficient and less-energy intensive processes for separation of CO{sub 2} selectively without the negative impacts of co-existing gases such as H{sub 2}O, O{sub 2}, and N{sub 2}; (3) replace a hazardous or less-effective substance in existing processes with CO{sub 2} as an alternate medium or solvent or co-reactant or a combination of them; (4) make use of CO{sub 2} based on the unique

  15. The correlationship between the metabolizable energy content, chemical composition and color score in different sources of corn DDGS

    Institute of Scientific and Technical Information of China (English)

    Yong-Z Jie; Jian-Y Zhang; Li-H Zhao; Qiu-G Maand Cheng Ji

    2014-01-01

    Background:This study was conducted to evaluate the apparent metabolizable energy (AME) and true metabolizable energy (TME) contents in 30 sources of corn distillers dried grains with solubles (DDGS) in adult roosters, and establish the prediction equations to estimate the AME and TME value based on its chemical Methods:Twenty-eight sources of corn DDGS made from several processing plants in 11 provinces of China and others imported from the United States. DDGS were analyzed for their metabolizable energy (ME) contents, measured for color score and chemical composition (crude protein, crude fat, ash, neutral detergent fiber, acid detergent fiber), to predict the equation of ME in DDGS. A precision-fed rooster assay was used, each DDGS sample was tube fed (50 g) to adult roosters. The experiment was conducted as a randomized incomplete block design with 3 periods. Ninety-five adult roosters were used in each period, with 90 being fed the DDGS samples and 5 being fasted to estimate basal endogenous energy losses. Results:Results showed that the AME ranged from 5.93 to 12.19 MJ/kg, TME ranged from 7.28 to 13.54 MJ/kg. Correlations were found between ME and ash content (-0.64, P<0.01) and between ME and yellowness score (0.39, P<0.05) of the DDGS samples. Furthermore, the best-fit regression equation for AME content of DDGS based on chemical composition and color score was AME=6.57111+0.51475 GE-0.10003 NDF+0.13380 ADF+0.07057 fat-0.57029 ash-0.02437 L (R2=0.70). The best-fit regression equation for TME content of DDGS was TME=7.92283+0.51475 GE-0.10003 NDF+0.13380 ADF+0.07057 fat-0.57029 ash-0.02437 L (R2=0.70). Conclusions:This experiment suggested that measuring the chemical composition and color score of a corn DDGS sample may provide a quality parameter for identifying corn DDGS sources energy digestibility and metabolizable energy content.

  16. Direct measurements of the energy flux due to chemical reactions at the surface of a silicon sample interacting with a SF6 plasma

    CERN Document Server

    Dussart, Remi; Pichon, Laurianne E; Bedra, Larbi; Semmar, Nadjib; Lefaucheux, Philippe; Mathias, Jacky; Tessier, Yves; 10.1063/1.2995988

    2008-01-01

    Energy exchanges due to chemical reactions between a silicon surface and a SF6 plasma were directly measured using a heat flux microsensor (HFM). The energy flux evolution was compared with those obtained when only few reactions occur at the surface to show the part of chemical reactions. At 800 W, the measured energy flux due to chemical reactions is estimated at about 7 W.cm\\^{-2} against 0.4 W.cm\\^{-2} for ion bombardment and other contributions. Time evolution of the HFM signal is also studied. The molar enthalpy of the reaction giving SiF4 molecules was evaluated and is consistent with values given in literature.

  17. 能源化工产业节能减排新模式%New mode of energy saving and emission reduction in energy chemical industry

    Institute of Scientific and Technical Information of China (English)

    李大鹏

    2012-01-01

    The status of energy chemical industry in Northern Shaanxi is briefly introduced. The development situation of a variety of comprehensive utilization of resources and the carbon dioxide capture, utilization and storage (CCUS) industry which are implemented by Yanchang Petroleum Group is presented in detail. The advantages of Jingbian Project about raising the utilization rate of resources and saving energy and reducing emission are illustrated. Yanchang Petroleum group is exploring the new pattern of energy saving and emission reduction in energy and chemical industry, and walking a new path of economic construction and environmental protection coordinated development.%简述了陕北地区能源化工产业的现状,详细介绍了延长石油实施多种资源综合利用及二氧化碳的捕获、利用与封存(CCUS)产业的发展情况,重点介绍了靖边项目在提高资源利用率和节能减排方面的优势.对能源化工产业节能减排新模式进行了探索,走经济建设和环境保护协调发展的产业道路.

  18. Chemical and radiological risk factors associated with waste from energy production

    DEFF Research Database (Denmark)

    Christensen, T.; Fuglestvedt, J.; Benestad, C.;

    1992-01-01

    potential impact of different sources and substances on human health. Existing concentration limits for effects on human health are used. The philosophy behind establishing limits for several carcinogenic chemicals is based on a linear dose-effect curve. That is, no lower concentration of no effect exists...

  19. Symposium on the Physical Chemistry of Solar Energy Conversion, Indianapolis American Chemical Society Meetings, Fall 2013

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Tianquan [PI, Emory Univ.

    2013-09-20

    The Symposium on the Physical Chemistry of Solar Energy Conversion at the Fall ACS Meeting in Indianapolis, IN (Sept. 8-12) featured the following sessions (approx. 6 speakers per session): (1) Quantum Dots and Nanorods for Solar Energy Conversion (2 half-day sessions); (2) Artificial Photosynthesis: Water Oxidation; (3) Artificial Photosynthesis: Solar Fuels (2 half-day sessions); (4) Organic Solar Cells; (5) Novel Concepts for Solar Energy Conversion (2 half-day sessions); (6) Emerging Techniques for Solar Energy Conversion; (7) Interfacial Electron Transfer

  20. Automated fit of high-dimensional potential energy surfaces using cluster analysis and interpolation over descriptors of chemical environment.

    Science.gov (United States)

    Fournier, René; Orel, Slava

    2013-12-21

    We present a method for fitting high-dimensional potential energy surfaces that is almost fully automated, can be applied to systems with various chemical compositions, and involves no particular choice of function form. We tested it on four systems: Ag20, Sn6Pb6, Si10, and Li8. The cost for energy evaluation is smaller than the cost of a density functional theory (DFT) energy evaluation by a factor of 1500 for Li8, and 60,000 for Ag20. We achieved intermediate accuracy (errors of 0.4 to 0.8 eV on atomization energies, or, 1% to 3% on cohesive energies) with rather small datasets (between 240 and 1400 configurations). We demonstrate that this accuracy is sufficient to correctly screen the configurations with lowest DFT energy, making this function potentially very useful in a hybrid global optimization strategy. We show that, as expected, the accuracy of the function improves with an increase in the size of the fitting dataset. PMID:24359355

  1. Genotoxicity, inflammation and physico-chemical properties of fine particle samples from an incineration energy plant and urban air

    DEFF Research Database (Denmark)

    Sharma, Anoop Kumar; Jensen, Keld Alstrup; Rank, Jette;

    2007-01-01

    Airborne particulate matter (PM) was sampled by use of an electrostatic sampler in an oven hall and a receiving hall in a waste-incineration energy plant, and from urban air in a heavy-traffic street and from background air in Copenhagen. PM was sampled for 1-2 weeks, four samples at each site. The......), but the distribution was completely different in the oven hall (maximum mode at about 150 nm). Also chemically, the samples from the oven hall were highly different from the other samples. PM extracts from the receiving hall, street and background air were more mutagenic than the PM extracts from the...... locations in particle size distribution, chemical composition and the resulting biological effects when A549 cells were incubated with the PM. These characteristics and observations in the oven hall indicated that the PM source was oven exhaust, which was well combusted. (c) 2007 Elsevier B.V. All rights...

  2. Chemical characterization of Lemna or 'Lenteja de Agua' from Titicaca Lake by energy dispersive x-ray fluorescence technique

    International Nuclear Information System (INIS)

    The objective of this work has been the chemical characterization of the Lemna or 'lenteja de agua', existing in the superficial water of the Lake Titicaca, the samples have been submitted to a rigorous process of cleaning, drying, crushing and shattering in a mortar of agate and pelletized to a 25 mm diameter into a hydraulic press. The samples were analyzed by Energy Dispersive X-Ray Fluorescence (EDXRF) technique, utilizing two XRF systems, one with radioactive Sources and another with an X-rays tube with Gadolinium and an assembly of secondary targets as excitation sources. The elements Al, Si, P, S, Cl, K, Ca, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Sb, Ba, Pb were determined in its chemical composition. (orig.)

  3. The investigation of chemical interaction and energy level alignment at Bepp2/Fe65Co35 interface

    Science.gov (United States)

    Wang, Zhen; Pan, Weiwei; Wang, Jinguo; Xu, Chunlong; Hou, Zhaoyang; Zuo, Yalu; Xi, Li

    2016-05-01

    In a bilayer system of Bepp2-FeCo, the element content variation and chemical states of the Bepp2-FeCo interface were investigated using X-ray and ultraviolet photoelectron spectroscopy with Ar ion etching. Chemical reaction was observed for Co and Fe with Bepp2 at the interface. Ultraviolet photoelectron spectroscopy results showed a downward energy shift of -1.0 eV at the interface. This behavior was attributed to the formation of an interface dipole layer. The hole injection barrier ΦpB was 2.0 eV, and the electronic injection barrier ΦnB was 0.6 eV. Moreover, only as the FeCo thickness is less than 3 nm, an uniaxial anisotropy can be induced on the organic layer with the investigation of magnetic optical Kerr effect, this can be used as a multi-function devices.

  4. Non-Friedmann cosmology for the Local Universe, significance of the universal Hubble constant, and short-distance indicators of dark energy

    Science.gov (United States)

    Chernin, A. D.; Teerikorpi, P.; Baryshev, Yu. V.

    2006-09-01

    Based on the increasing evidence of the cosmological relevance of the local Hubble flow, we consider a simple analytical cosmological model for the Local Universe. This is a non-Friedmann model with a non-uniform static space-time. The major dynamical factor controlling the local expansion is the antigravity produced by the omnipresent and permanent dark energy of the cosmic vacuum (or the cosmological constant). The antigravity dominates at larger distances than 1-2 Mpc from the center of the Local group. The model gives a natural explanation of the two key quantitative characteristics of the local expansion flow, which are the local Hubble constant and the velocity dispersion of the flow. The observed kinematical similarity of the local and global flows of expansion is clarified by the model. We analytically demonstrate the efficiency of the vacuum cooling mechanism that allows one to see the Hubble law this close to the Local group. The "universal Hubble constant" HV (≈60 km s-1 Mpc-1), depending only on the vacuum density, has special significance locally and globally. The model makes a number of verifiable predictions. It also unexpectedly shows that the dwarf galaxies of the local flow with the shortest distances and lowest redshifts may be the most sensitive indicators of dark energy in our neighborhood.

  5. Le traitement des déchets polymères : la valorisation énergétique ou chimique Treatment of Polymer Wastes: Chemical Or Energy Upgrading

    Directory of Open Access Journals (Sweden)

    Dawans F.

    2006-11-01

    Full Text Available Une protection accrue de l'environnement requiert la mise en place de nouvelles techniques fiables et économiques de traitement des déchets polymères. Parmi les diverses méthodes envisagées pour la réutilisation ou l'élimination des polymères usagés, les recyclages énergétiques et chimiques peuvent apporter des solutions satisfaisantes et complémentaires au recyclage de la matière. Cet article fait le point sur l'état d'avancement des techniques de valorisation énergétique et chimique des rejets de polymères et il propose une analyse critique des traitements actuels. Increased environmental protection requires the installation of new treatment techniques for polymer wastes. Competitive industrial facilities are not available from the economic standpoint for recycling spent plastic and rubber wastes in the form of materials, especially when mixtures are involved. It is only by using other treatment method for the chemical or energy upgrading of polymers, as a supplement to the recycling of materials, that it should be possible to make a significant reduction in the amount of spent polymers currently being scrapped. The energy upgrading of wastes by incineration with energy recovery or by pyrolysis with the formation of fuels in an interesting approach for a great many countries. When no reuse is possible, the energy content of the material is upgraded before the subsequent scrapping of an ultimate residue that is reduced to its incompressible minimum after having been inerted. There are currently several technical solutions for incineration furnaces and the treatment of the fumes produced, which meet the more and more severe requirements concerning environmental protection. Incineration systems with energy recovery can recover about 8000 thermies per ton of unsorted plastics. They already have an important position, albeit a varying one, from one European country to another (Table 6. They should develop considerably further in

  6. The Issue of Calculating the Final Temperature of the Products of Rapid Exothermic Chemical Reactions with Significant Energy Release in a Closed Volume

    Science.gov (United States)

    Lazarev, V.; Geidmanis, D.

    2016-02-01

    The theoretical problem solved in this article is the calculation of thermodynamic parameters such as final temperature, distribution of the liquid and dry saturated vapour phases of the substance that are considered to be in thermodynamic equilibrium, and pressure of the system of several reaction products after adding to the system a certain amount of heat or the thermal effect released during rapid exothermic reaction in a closed volume that occurs so fast that it can be considered to be adiabatic, and when the volume of liquid reagents is several orders of magnitude less than the volume of the reactor. The general multi-substance problem is reduced to a theoretical problem for one substance of calculation thermodynamic parameters of system after adding a certain amount of heat that gives theoretically rigorous isochoric calculation. In this article, we substantiate our view that isochoric pass of calculation is more robust compared to seemingly more natural isobaric pass of calculation, if the later involves quite not trivial calculation of the adiabatic compression of a two-phase system (liquid - dry saturated vapour) that can pass itself into another kind of state (liquid - wet saturated vapour), which requires, apparently, more complex descriptions compared with isochoric calculation because the specific heat capacity of wet saturated vapour can be negative. The solved theoretical problem relates to a practical problem that has been a driver for our research as part of a design of the reactor of the titanium reduction from magnesium and titanium tetrachloride supplied into atmosphere of the reactor at high temperatures when both reagents are in gaseous state. The reaction is known to be exothermic with a high thermal effect, and estimate of the final temperature and pressure of the products of reaction, for instance, designing the reactor allows eliminating the possibility of the reaction products to penetrate backwards into supply tracts of the reagents. Using a rigid theoretical approach and heuristics of thermodynamic parameters of reaction products available in the literature, we have presented a graphical dependence of final temperature, pressure ratio of the liquid and vapour state of titanium after the reaction on the initial temperature of the reactor and magnesium in the range of 1200-1800 °K while titanium tetrachloride is injected into reactor at its critical temperature.

  7. Development of Bi-phase sodium-oxygen-hydrogen chemical equilibrium calculation program (BISHOP) using Gibbs free energy minimization method

    Energy Technology Data Exchange (ETDEWEB)

    Okano, Yasushi [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1999-08-01

    In order to analyze the reaction heat and compounds due to sodium combustion, the multiphase chemical equilibrium calculation program for chemical reaction among sodium, oxygen and hydrogen is developed in this study. The developed numerical program is named BISHOP; which denotes Bi-Phase, Sodium - Oxygen - Hydrogen, Chemical Equilibrium Calculation Program'. Gibbs free energy minimization method is used because of the special merits that easily add and change chemical species, and generally deal many thermochemical reaction systems in addition to constant temperature and pressure one. Three new methods are developed for solving multi-phase sodium reaction system in this study. One is to construct equation system by simplifying phase, and the other is to expand the Gibbs free energy minimization method into multi-phase system, and the last is to establish the effective searching method for the minimum value. Chemical compounds by the combustion of sodium in the air are calculated using BISHOP. The Calculated temperature and moisture conditions where sodium-oxide and hydroxide are formed qualitatively agree with the experiments. Deformation of sodium hydride is calculated by the program. The estimated result of the relationship between the deformation temperature and pressure closely agree with the well known experimental equation of Roy and Rodgers. It is concluded that BISHOP can be used for evaluated the combustion and deformation behaviors of sodium and its compounds. Hydrogen formation condition of the dump-tank room at the sodium leak event of FBR is quantitatively evaluated by BISHOP. It can be concluded that to keep the temperature of dump-tank room lower is effective method to suppress the formation of hydrogen. In case of choosing the lower inflammability limit of 4.1 mol% as the hydrogen concentration criterion, formation reaction of sodium hydride from sodium and hydrogen is facilitated below the room temperature of 800 K, and concentration of

  8. Development of Bi-phase sodium-oxygen-hydrogen chemical equilibrium calculation program (BISHOP) using Gibbs free energy minimization method

    International Nuclear Information System (INIS)

    In order to analyze the reaction heat and compounds due to sodium combustion, the multiphase chemical equilibrium calculation program for chemical reaction among sodium, oxygen and hydrogen is developed in this study. The developed numerical program is named BISHOP; which denotes Bi-Phase, Sodium - Oxygen - Hydrogen, Chemical Equilibrium Calculation Program'. Gibbs free energy minimization method is used because of the special merits that easily add and change chemical species, and generally deal many thermochemical reaction systems in addition to constant temperature and pressure one. Three new methods are developed for solving multi-phase sodium reaction system in this study. One is to construct equation system by simplifying phase, and the other is to expand the Gibbs free energy minimization method into multi-phase system, and the last is to establish the effective searching method for the minimum value. Chemical compounds by the combustion of sodium in the air are calculated using BISHOP. The Calculated temperature and moisture conditions where sodium-oxide and hydroxide are formed qualitatively agree with the experiments. Deformation of sodium hydride is calculated by the program. The estimated result of the relationship between the deformation temperature and pressure closely agree with the well known experimental equation of Roy and Rodgers. It is concluded that BISHOP can be used for evaluated the combustion and deformation behaviors of sodium and its compounds. Hydrogen formation condition of the dump-tank room at the sodium leak event of FBR is quantitatively evaluated by BISHOP. It can be concluded that to keep the temperature of dump-tank room lower is effective method to suppress the formation of hydrogen. In case of choosing the lower inflammability limit of 4.1 mol% as the hydrogen concentration criterion, formation reaction of sodium hydride from sodium and hydrogen is facilitated below the room temperature of 800 K, and concentration of hydrogen

  9. Chemical effects of lanthanides and actinides in glasses determined with electron energy loss spectroscopy

    International Nuclear Information System (INIS)

    Chemical and structural environments of f-electron elements in glasses are the origin of many of the important properties of materials with these elements; thus oxidation state and chemical coordination of lanthanides and actinides in host materials is an important design consideration in optically active glasses, magnetic materials, perovskite superconductors, and nuclear waste materials. We have made use of the line shapes of Ce to determine its oxidation state in alkali borosilicate glasses being developed for immobilization of Pu. Examination of several prototype waste glass compositions with EELS shows that the redox state of Ce doped to 7 wt% could be varied by suitable choice of alkali elements. EELS for a Pu-doped glass illustrate the small actinide N4/N5 intensity ratio and show that the Pu-N4,5 white line cross section is comparable to that of Gd M4,5

  10. Methanogenesis as a potential source of chemical energy for primary biomass production by autotrophic organisms in hydrothermal systems on Europa

    Science.gov (United States)

    McCollom, Thomas M.

    Geochemical models are used to explore the possibility that lithoautotrophic methanogenesis (the conversion of CO2 plus H2 to methane) could be a source of metabolically useful chemical energy for the production of biomass at putative European hydrothermal systems. Two cases are explored: a relatively reduced methane-rich ocean and a relatively oxidized sulfate-and bicarbonate-rich ocean. In the case of a methane-rich ocean, a source of CO2 for methanogenesis is provided by conversion of dissolved methane to CO2 during reaction of ocean water with igneous rocks at high temperatures in the subsurface. Fluid-rock reactions also provide a source of dissolved H2 in the hydrothermal fluid. When this fluid circulates back to the ocean floor and mixes with seawater, conversion of the dissolved CO2 and H2 to methane provides a potential source of chemical energy that can be used to drive metabolic processes. For the case of a sulfate- and carbonate-rich ocean, reaction with reduced igneous rocks at high temperatures will also produce hydrothermal fluids with high H2 concentrations (as occurs in hydrothermal systems on Earth). Mixing of the resulting hydrothermal fluid with seawater in a relatively oxidized ocean could supply energy from either methanogenesis or sulfate reduction. For plausible compositions of a European ocean, methanogenesis can supply similar amounts of energy to that which supports the prolific ecosystems surrounding submarine hydrothermal vents on Earth. Even in the most optimistic case, however, the total amount of biomass that could be supported globally by lithoautotrophic microbes on Europa is extremely small compared to the biomass produced photosynthetically on Earth. Nevertheless, sufficient metabolic energy could apparently be available at hydrothermal systems on Europa to support an origin of life and localized ecosystems.

  11. Kinetic mechanism of molecular energy transfer and chemical reactions in low-temperature air-fuel plasmas.

    Science.gov (United States)

    Adamovich, Igor V; Li, Ting; Lempert, Walter R

    2015-08-13

    This work describes the kinetic mechanism of coupled molecular energy transfer and chemical reactions in low-temperature air, H2-air and hydrocarbon-air plasmas sustained by nanosecond pulse discharges (single-pulse or repetitive pulse burst). The model incorporates electron impact processes, state-specific N2 vibrational energy transfer, reactions of excited electronic species of N2, O2, N and O, and 'conventional' chemical reactions (Konnov mechanism). Effects of diffusion and conduction heat transfer, energy coupled to the cathode layer and gasdynamic compression/expansion are incorporated as quasi-zero-dimensional corrections. The model is exercised using a combination of freeware (Bolsig+) and commercial software (ChemKin-Pro). The model predictions are validated using time-resolved measurements of temperature and N2 vibrational level populations in nanosecond pulse discharges in air in plane-to-plane and sphere-to-sphere geometry; temperature and OH number density after nanosecond pulse burst discharges in lean H2-air, CH4-air and C2H4-air mixtures; and temperature after the nanosecond pulse discharge burst during plasma-assisted ignition of lean H2-mixtures, showing good agreement with the data. The model predictions for OH number density in lean C3H8-air mixtures differ from the experimental results, over-predicting its absolute value and failing to predict transient OH rise and decay after the discharge burst. The agreement with the data for C3H8-air is improved considerably if a different conventional hydrocarbon chemistry reaction set (LLNL methane-n-butane flame mechanism) is used. The results of mechanism validation demonstrate its applicability for analysis of plasma chemical oxidation and ignition of low-temperature H2-air, CH4-air and C2H4-air mixtures using nanosecond pulse discharges. Kinetic modelling of low-temperature plasma excited propane-air mixtures demonstrates the need for development of a more accurate 'conventional' chemistry mechanism

  12. Chemical Profiles of Wood Components of Poplar Clones for Their Energy Utilization

    Directory of Open Access Journals (Sweden)

    Danica Kačíková

    2012-12-01

    Full Text Available Selected and tested poplar clones are very suitable biomass resources for various applications such as biofuels, the pulp and paper industry as well as chemicals production. In this study, we determined the content of lignin, cellulose, holocellulose, and extractives, syringyl to guaiacyl (S/G ratio in lignin, and also calculated higher heating values (HHV among eight examined clones of Populus grown on three different experimental sites. The highest lignin content for all the examined sites was determined in ‘I-214’ and ‘Baka 5’ clones, whereas the highest content of extractives was found in ‘Villafranca’ and ‘Baka 5’ clones. The highest S/G ratio for all the examined sites was determined in ‘Villafranca’ and ‘Agathe F’ clones. The chemical profiles of main wood components, extractives, and the S/G ratio in lignin were also influenced by both the experimental site and the clone × site interaction. Higher heating values, derived from calculations based on the contents of lignin and extractives (or lignin only, were in close agreement with the previously published data. The highest heating values were found for ‘Baka 5’ and ‘I-214’ clones. The optimal method of poplar biomass utilization can be chosen on basis of the lignocellulosics chemical composition and the S/G ratio in lignin.

  13. Chemical looping combustion: A new low-dioxin energy conversion technology.

    Science.gov (United States)

    Hua, Xiuning; Wang, Wei

    2015-06-01

    Dioxin production is a worldwide concern because of its persistence and carcinogenic, teratogenic, and mutagenic effects. The pyrolysis-chemical looping combustion process of disposing solid waste is an alternative to traditional solid waste incineration developed to reduce the dioxin production. Based on the equilibrium composition of the Deacon reaction, pyrolysis gas oxidized by seven common oxygen carriers, namely, CuO, NiO, CaSO4, CoO, Fe2O3, Mn3O4, and FeTiO3, is studied and compared with the pyrolysis gas directly combusted by air. The result shows that the activity of the Deacon reaction for oxygen carriers is lower than that for air. For four typical oxygen carriers (CuO, NiO, Fe2O3, and FeTiO3), the influences of temperature, pressure, gas composition, and tar on the Deacon reaction are discussed in detail. According to these simulation results, the dioxin production in China, Europe, the United States, and Japan is predicted for solid waste disposal by the pyrolysis-chemical looping combustion process. Thermodynamic analysis results in this paper show that chemical looping combustion can reduce dioxin production in the disposal of solid waste. PMID:26040740

  14. Harvest and utilization of chemical energy in wastes by microbial fuel cells.

    Science.gov (United States)

    Sun, Min; Zhai, Lin-Feng; Li, Wen-Wei; Yu, Han-Qing

    2016-05-21

    Organic wastes are now increasingly viewed as a resource of energy that can be harvested by suitable biotechnologies. One promising technology is microbial fuel cells (MFC), which can generate electricity from the degradation of organic pollutants. While the environmental benefits of MFC in waste treatment have been recognized, their potential as an energy producer is not fully understood. Although progresses in material and engineering have greatly improved the power output from MFC, how to efficiently utilize the MFC's energy in real-world scenario remains a challenge. In this review, fundamental understandings on the energy-generating capacity of MFC from real waste treatment are provided and the challenges and opportunities are discussed. The limiting factors restricting the energy output and impairing the long-term reliability of MFC are also analyzed. Several energy storage and in situ utilization strategies for the management of MFC's energy are proposed, and future research needs for real-world application of this approach are explored. PMID:26936021

  15. Comparison between conventional chemical processes and bioprocesses in cotton fabrics

    OpenAIRE

    Mojsov, Kiro

    2015-01-01

    Textile processing is a growing industry that traditionally has used a lot of water, energy and harsh chemicals. They are also not easily biodegradable. Biotechnology in textiles is one of the revolutionary ways to promote the textile field. Bio-processing were accompanied by a significant lower demand of energy, water, chemicals, time and costs. Due to the ever growing costs for water and energy worldwide investigations are carried out to substitute conventional chemical textile processes by...

  16. Thermodynamics of chemical free energy generation in off-axis hydrothermal vent systems and its consequences for compartmentalization and the emergence of life

    CERN Document Server

    Simoncini, E; Gallori, E; .,

    2010-01-01

    In this paper we demonstrate how chemical free energy can be produced by a geological process. We provide a thermodynamic framework in which to assess how life emerged at the off-axis hydrothermal vent system; the RNA - clays system has been investigated from the entropic point of view, showing that the stabilization of the system in a state further away from equilibrium state, by an inorganic heterogeneous compartmetalization phenomena, is able to produce chemical free energy useful for RNA self - replication.

  17. X-Ray Photoelectron Spectroscopy and the Role of Relaxation Energy in Understanding Chemical Shifts

    Science.gov (United States)

    Ellison, Frank O.; White, Michael G.

    1976-01-01

    Discusses the measurement of electrons ejected from a system which is being irradiated with X-rays or ultraviolet photons, and a theoretical model for calculating core-electron ionization energies. (MLH)

  18. Research on high-energy chemical reactions. Annual progress report, August 1, 1974--October 31, 1975

    International Nuclear Information System (INIS)

    Product yields for the reactions T* + c - C6D12 → c - C6D11T, DT have been measured using a beam of T* formed by charge exchange in the energy range of 25 eV to 100 eV. A computer program was written to calculate the probability of collision vs. energy of a beam of T* moderated by He gas

  19. Characterization of Physico-Chemical and Spectroscopic Properties of Biofield Energy Treated 4-Bromoacetophenone

    OpenAIRE

    Trivedi, Mahendra Kumar

    2015-01-01

    4-Bromoacetophenone is an acetophenone derivative known for its usefulness in organic coupling reactions and various biological applications. The aim of the study was to evaluate the impact of biofield energy treatment on 4-bromoacetophenone using various analytical methods. The material is divided into two groups for this study i.e. control and treated. The control group remained as untreated and the treated group was subjected to Mr. Trivedi’s biofield energy treatment. Then, both the...

  20. Quantum-chemical modeling of energy parameters and vibrational spectra of chain and cyclic clusters of monohydric alcohols

    International Nuclear Information System (INIS)

    The specific peculiarities of alcohols such as heightened viscosity, boiling temperature and surface tension can be explained by the capability of their molecules to form relatively stable associates named clusters due to hydrogen bonding. In present work the stability of different chain-like and cyclic clusters of methanol, ethanol, 1-propanol, 1-butanol, 1-pentanol and 1-hexanol was investigated by means of quantum-chemical simulation and particular by recently developed DFT exchange–correlation functional M06-2X. The relative stability of the cluster structure was evaluated by the total energy per molecule at low temperatures (where all alcohols exist in solid state) and by the changing of the free Gibbs energy upon cluster formation at the room temperature. For the verification of revealed results the conformity of calculated IR spectra of the most stable cluster structures with the experimental IR spectra at different temperatures was analyzed.

  1. The Microstructure and Chemical Bonds of β-C2S Under the High Energy Ball Grinding Function

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Using the laser granularity survey technology, X- ray powder diffraction, scanning electron mi croscopy (SEM) and infrared spectrum analysis methods, we studied the microscopic structure and chemical bonds changes of β- C2 S monomineral under the high energy ball grinding function .The result indicates that, continuously under the mechanical power, β-C2 S crystal size would decrease, the micro strain and the effective Beff parameter would increase, and the amorphous phases would be presented. Furthermore, the mechanical power would cause Si- O bond broken and reorganized, the specific surface area would increase, the energy of micro-pow der agglomeration vibration would be enhanced and the crystal would be disordered .Finally, β- C2 S was caused to have the mechanochemical change and the activity enhancement.

  2. Alliance between chemical industry Astral Calcining, India, and energy company E.On Benelux; Verbond chemie en energie [tussen Astral Calcining, India en E.On Benelux

    Energy Technology Data Exchange (ETDEWEB)

    Roggen, M. (ed.)

    2003-03-01

    The Indian chemical concern Astral Calcining (produces carbon for the aluminium industry) will supply high-pressure steam to the energy company E.ON Benelux, to be used by Lyondell Bayer (producer of propylene oxide). In exchange, Astral will receive electricity from E.On Benelux. This is a unique co-operation between companies with different production processes and cultures. [Dutch] Het Indiase chemieconcern Astral gaat aan E.ON Benelux hogedruk stoom leveren die bestemd is voor Lyondell Bayer. In ruil daarvoor ontvangt Astral elektriciteit. Een unieke samenwerking tussen concerns met totaal andere productieprocessen en uiteenlopende culturen.

  3. Predicting Formation Damage in Aquifer Thermal Energy Storage Systems Utilizing a Coupled Hydraulic-Thermal-Chemical Reservoir Model

    Science.gov (United States)

    Müller, Daniel; Regenspurg, Simona; Milsch, Harald; Blöcher, Guido; Kranz, Stefan; Saadat, Ali

    2014-05-01

    In aquifer thermal energy storage (ATES) systems, large amounts of energy can be stored by injecting hot water into deep or intermediate aquifers. In a seasonal production-injection cycle, water is circulated through a system comprising the porous aquifer, a production well, a heat exchanger and an injection well. This process involves large temperature and pressure differences, which shift chemical equilibria and introduce or amplify mechanical processes. Rock-fluid interaction such as dissolution and precipitation or migration and deposition of fine particles will affect the hydraulic properties of the porous medium and may lead to irreversible formation damage. In consequence, these processes determine the long-term performance of the ATES system and need to be predicted to ensure the reliability of the system. However, high temperature and pressure gradients and dynamic feedback cycles pose challenges on predicting the influence of the relevant processes. Within this study, a reservoir model comprising a coupled hydraulic-thermal-chemical simulation was developed based on an ATES demonstration project located in the city of Berlin, Germany. The structural model was created with Petrel, based on data available from seismic cross-sections and wellbores. The reservoir simulation was realized by combining the capabilities of multiple simulation tools. For the reactive transport model, COMSOL Multiphysics (hydraulic-thermal) and PHREEQC (chemical) were combined using the novel interface COMSOL_PHREEQC, developed by Wissmeier & Barry (2011). It provides a MATLAB-based coupling interface between both programs. Compared to using COMSOL's built-in reactive transport simulator, PHREEQC additionally calculates adsorption and reaction kinetics and allows the selection of different activity coefficient models in the database. The presented simulation tool will be able to predict the most important aspects of hydraulic, thermal and chemical transport processes relevant to

  4. Chemical bond as a test of density-gradient expansions for kinetic and exchange energies

    International Nuclear Information System (INIS)

    Errors in kinetic and exchange contributions to the molecular bonding energy are assessed for approximate density functionals by reference to near-exact Hartree-Fock values. From the molecular calculations of Allan et al. and of Lee and Ghosh, it is demonstrated that the density-gradient expansion does not accurately describe the noninteracting kinetic contribution to the bonding energy, even when this expansion is carried to fourth order and applied in its spin-density-functional form to accurate Hartree-Fock densities. In a related study, it is demonstrated that the overbinding of molecules such as N2 and F2, which occurs in the local-spin-density (LSD) approximation for the exchange-correlation energy, is not attributable to errors in the self-consistent LSD densities. Contrary to expectations based upon the Gunnarsson-Jones nodality argument, it is found that the LSD approximation for the exchange energy can seriously overbind a molecule even when bonding does not create additional nodes in the occupied valence orbitals. LSD and exact values for the exchange contribution to the bonding energy are displayed and discussed for several molecules

  5. Equilibrium Chemical Engines

    OpenAIRE

    Shibata, Tatsuo; Sasa, Shin-ichi

    1997-01-01

    An equilibrium reversible cycle with a certain engine to transduce the energy of any chemical reaction into mechanical energy is proposed. The efficiency for chemical energy transduction is also defined so as to be compared with Carnot efficiency. Relevance to the study of protein motors is discussed. KEYWORDS: Chemical thermodynamics, Engine, Efficiency, Molecular machine.

  6. Energy Effectiveness of Direct UV and UV/H2O2 Treatment of Estrogenic Chemicals in Biologically Treated Sewage

    Directory of Open Access Journals (Sweden)

    Kamilla M. S. Hansen

    2012-01-01

    Full Text Available Continuous exposure of aquatic life to estrogenic chemicals via wastewater treatment plant effluents has in recent years received considerable attention due to the high sensitivity of oviparous animals to disturbances of estrogen-controlled physiology. The removal efficiency by direct UV and the UV/H2O2 treatment was investigated in biologically treated sewage for most of the estrogenic compounds reported in wastewater. The investigated compounds included parabens, industrial phenols, sunscreen chemicals, and steroid estrogens. Treatment experiments were performed in a flow through setup. The effect of different concentrations of H2O2 and different UV doses was investigated for all compounds in an effluent from a biological wastewater treatment plant. Removal effectiveness increased with H2O2 concentration until 60 mg/L. The treatment effectiveness was reported as the electrical energy consumed per unit volume of water treated required for 90% removal of the investigated compound. It was found that the removal of all the compounds was dependent on the UV dose for both treatment methods. The required energy for 90% removal of the compounds was between 28 kWh/m3 (butylparaben and 1.2 kWh/m3 (estrone for the UV treatment. In comparison, the UV/H2O2 treatment required between 8.7 kWh/m3 for bisphenol A and benzophenone-7 and 1.8 kWh/m3 for ethinylestradiol.

  7. Life-cycle fossil energy consumption and greenhouse gas emissions of bioderived chemicals and their conventional counterparts.

    Science.gov (United States)

    Adom, Felix; Dunn, Jennifer B; Han, Jeongwoo; Sather, Norm

    2014-12-16

    Biomass-derived chemical products may offer reduced environmental impacts compared to their fossil-derived counterparts and could improve profit margins at biorefineries when coproduced with higher-volume, lower-profit margin biofuels. It is important to assess on a life-cycle basis the energy and environmental impacts of these bioproducts as compared to conventional, fossil-derived products. We undertook a life-cycle analysis of eight bioproducts produced from either algal-derived glycerol or corn stover-derived sugars. Selected on the basis of technology readiness and market potential, the bioproducts are propylene glycol, 1,3-propanediol, 3-hydroxypropionic acid, acrylic acid, polyethylene, succinic acid, isobutanol, and 1,4-butanediol. We developed process simulations to obtain energy and material flows in the production of each bioproduct and examined sensitivity of these flows to process design assumptions. Conversion process data for fossil-derived products were based on the literature. Conversion process data were combined with upstream parameters in the Greenhouse gases, Regulated Emissions, and Energy use in Transportation (GREET) model to generate life-cycle greenhouse gas (GHG) emissions and fossil energy consumption (FEC) for each bioproduct and its corresponding petroleum-derived product. The bioproducts uniformly offer GHG emissions reductions compared to their fossil counterparts ranging from 39 to 86% on a cradle-to-grave basis. Similarly, FEC was lower for bioproducts than for conventional products. PMID:25380298

  8. Characterisation of chemical composition and energy content of green waste and municipal solid waste from Greater Brisbane, Australia.

    Science.gov (United States)

    Hla, San Shwe; Roberts, Daniel

    2015-07-01

    The development and deployment of thermochemical waste-to-energy systems requires an understanding of the fundamental characteristics of waste streams. Despite Australia's growing interest in gasification of waste streams, no data are available on their thermochemical properties. This work presents, for the first time, a characterisation of green waste and municipal solid waste in terms of chemistry and energy content. The study took place in Brisbane, the capital city of Queensland. The municipal solid waste was hand-sorted and classified into ten groups, including non-combustibles. The chemical properties of the combustible portion of municipal solid waste were measured directly and compared with calculations made based on their weight ratios in the overall municipal solid waste. The results obtained from both methods were in good agreement. The moisture content of green waste ranged from 29% to 46%. This variability - and the tendency for soil material to contaminate the samples - was the main contributor to the variation of samples' energy content, which ranged between 7.8 and 10.7MJ/kg. The total moisture content of food wastes and garden wastes was as high as 70% and 60%, respectively, while the total moisture content of non-packaging plastics was as low as 2.2%. The overall energy content (lower heating value on a wet basis, LHVwb) of the municipal solid waste was 7.9MJ/kg, which is well above the World Bank-recommended value for utilisation in thermochemical conversion processes. PMID:25882791

  9. Evaluation of the viability and energy metabolism of canine pancreas graft subjected to significant warm ischemia damage during preservation by UW solution cold storage method

    Institute of Scientific and Technical Information of China (English)

    Chun-Hui Yuan; Gui-Chen Li; He Zhang; Ying Cheng; Ning Zhao; Yong-Feng Liu

    2004-01-01

    AIM: To evaluate the viability and energy metabolism of long warm ischemically damaged pancreas during preservation by the UW solution cold storage method.METHODS: The pancreas grafts subjected to 30-120 min warm ischemia were preserved by the UW solution cold storage method for 24 h. The tissue concentrations of adenine nucleotides (AN) and adenosine triphosphate (ATP)and total adenine nucleotides (TAN) were determined by using high performance liquid chromatography (HPLC) and the viability of the pancreas graft was tested in the canine model of segmental pancreas autotransplantation.RESULTS: The functional success rates of pancreas grafts of groups after 30 min, 60 min, 90 min, 120 min of warm ischemia were 100%, 100%, 67.7%, 0%, respectively.There was an excellent correlation between the posttransplant viability and tissue concentration of ATP and TAN at the end of preservation.CONCLUSION: The UW solution cold storage method was effective for functional recovery of the pancreas suffering 60-min warm ischemia. The tissue concentration of ATP and TAN at the end of 24 h preservation by the UW solution cold storage method would predict the posttransplant outcome of pancreas graft subjected to significant warm ischemia.

  10. Non-Friedmann cosmology for the Local Universe, significance of the universal Hubble constant and short-distance indicators of dark energy

    CERN Document Server

    Chernin, A D; Baryshev, Y V; Chernin, Arthur D.; Teerikorpi, Pekka; Baryshev, Yurij V.

    2006-01-01

    Basing on the increasing evidence for the cosmological relevance of the local Hubble flow, we consider a simple analytical cosmological model for the Local Universe. This is a non-Friedmann model with a non-uniform static space-time. The major dynamical factor controlling the local expansion is the antigravity produced by the omnipresent and permanent dark energy of the cosmic vacuum (or the cosmological constant). The antigravity dominates at distances larger than 1-2 Mpc from the center of the Local Group. The model gives a natural explanation of the two key quantitative characteristics of the local expansion flow, which are the local Hubble constant and the velocity dispersion of the flow. The observed kinematical similarity of the local and global flows of expansion is clarified by the model. We demonstrate analytically the efficiency of the vacuum cooling mechanism that allows one to see the Hubble flow so close to the Local Group. Special significance is argued for the 'universal Hubble constant' H_V, d...

  11. Large-scale quantum mechanical scattering calculations for molecular energy transfer and chemical reactions

    International Nuclear Information System (INIS)

    The authors discuss two projects involving quantal collision theory calculations on supercomputers. In the first project the authors are considering HF-HF collisions and calculating rotational energy transfer for collisions of rigid molecules and vibrational-to-vibrational (V-V) energy transfer for collisions including all degrees of freedom. They examined several potential energy surfaces, and they parametrized a new one that should be more accurate for the cross correlation of the forces. For rotational energy transfer they also compared the results to classical trajectory calculations. The quantal calculations were carried out by integrating the close coupling equations with scattering boundary conditions using an extensively vectorized R matrix propagation code on the Control Data Corporation Cyber 205 computer. In the second project they are considering atom-diatom reactive collisions for low initial rotational states and both the ground and first excited vibrational state. The three arrangement channels (A =BC, AB+C, and AC+B) are coupled by the Fock scheme, and the reactive amplitude density (obtained by operating on the initial state with the reactance operator or the total wave function with the interaction potential) is expanded in a square-integrable basis set. This leads to a large system of coupled algebraic equations which are constructed and solved using a large-memory Cray-2 computer. Variational improvements have been tested successfully for nonreactive collisions and will soon be implemented for reactive collisions

  12. Physical and chemical nature of the scaling relations between adsorption energies of atoms on metal surfaces

    DEFF Research Database (Denmark)

    Calle-Vallejo, F.; Martínez, J. I.; García Lastra, Juan Maria;

    2012-01-01

    phenomenon between any set of adsorbates bound similarly to the surface. On the example of the near-surface alloys of Pt, we show that scalability is a result of identical variations of adsorption energies with respect to the valence configuration of both the surface components and the adsorbates....

  13. Transport of low energy electrons in water and some physico-chemical implications

    International Nuclear Information System (INIS)

    Considerable effort by numerous groups is currently being devoted to measuring or calculating cross-sections for use as input to Monte-Carlo studies of radiation effects. We address the question of how well do low-energy cross-sections need to be known in order to calculate adequately quantities of interest in the radiobiological domain. 11 references, 4 figures

  14. Chemical Storage of Solar Energy Using an Old Color Change Demonstration.

    Science.gov (United States)

    Spears, L. Gene, Jr.; Spears, Larry G.

    1984-01-01

    Background information, procedures, and typical results are provided for an experiment illustrating the potential of hydrated salts for solar energy storage. The experiment involves a demonstration often used to illustrate the ease with which some transition metal ions can change their coordination numbers. (JN)

  15. Acoustic energy transfer to the upper atmosphere from surface chemical and underground nuclear explosions

    Czech Academy of Sciences Publication Activity Database

    Drobzheva, Yana Viktorovna; Krasnov, Valerij Michailovič

    2006-01-01

    Roč. 68, 3-5 (2006), s. 578-585. ISSN 1364-6826 R&D Projects: GA ČR GA205/04/2110 Institutional research plan: CEZ:AV0Z30420517 Keywords : Acoustic wave * Energy * Atmosphere * Ionosphere Subject RIV: DG - Athmosphere Sciences, Meteorology Impact factor: 1.448, year: 2006

  16. Significant concentration changes of chemical components of PM1 in the Yangtze River Delta area of China and the implications for the formation mechanism of heavy haze-fog pollution.

    Science.gov (United States)

    Zhang, Y W; Zhang, X Y; Zhang, Y M; Shen, X J; Sun, J Y; Ma, Q L; Yu, X M; Zhu, J L; Zhang, L; Che, H C

    2015-12-15

    Since the winter season of 2013, a number of persistent haze-fog events have occurred in central-eastern China. Continuous measurements of the chemical and physical properties of PM1 at a regional background station in the Yangtze River Delta area of China from 16 Nov. to 18 Dec., 2013 revealed several haze-fog events, among which a heavy haze-fog event occurred between 6 Dec. and 8 Dec. The mean concentration of PM1 was 212μgm(-3) in the heavy haze-fog period, which was about 10 times higher than on clean days and featured a peak mass concentration that reached 298μgm(-3). Organics were the largest contributor to the dramatic rise of PM1 on heavy haze-fog days (average mass concentration of 86μgm(-3)), followed by nitrate (58μgm(-3)), sulfate (35μgm(-3)), ammonium (29μgm(-3)), and chloride (4.0μgm(-3)). Nitrate exhibited the largest increase (~20 factors), associated with a significant increase in NOx. This was mainly attributable to increased coal combustion emissions, relative to motor vehicle emissions, and was caused by short-distance pollutant transport within surrounding areas. Low-volatility oxidized organic aerosols (OA) (LV-OOA) and biomass-burning OA (BBOA) also increased sharply on heavy haze-fog days, exhibiting an enhanced oxidation capacity of the atmosphere and increased emissions from biomass burning. The strengthening of the oxidation capacity during the heavy pollution episode, along with lower solar radiation, was probably due to increased biomass burning, which were important precursors of O3. The prevailing meteorological conditions, including low wind and high relative humidity, and short distance transported gaseous and particulate matter surrounding of the sampling site, coincided with the increased pollutant concentrations mainly from biomass-burning mentioned above to cause the persistent haze-fog event in the YRD area. PMID:26298245

  17. Chemical bonding in view of electron charge density and kinetic energy density descriptors.

    Science.gov (United States)

    Jacobsen, Heiko

    2009-05-01

    Stalke's dilemma, stating that different chemical interpretations are obtained when one and the same density is interpreted either by means of natural bond orbital (NBO) and subsequent natural resonance theory (NRT) application or by the quantum theory of atoms in molecules (QTAIM), is reinvestigated. It is shown that within the framework of QTAIM, the question as to whether for a given molecule two atoms are bonded or not is only meaningful in the context of a well-defined reference geometry. The localized-orbital-locator (LOL) is applied to map out patterns in covalent bonding interaction, and produces results that are consistent for a variety of reference geometries. Furthermore, LOL interpretations are in accord with NBO/NRT, and assist in an interpretation in terms of covalent bonding. PMID:19090572

  18. Development of catalysts for chemical reactions driven by concentrated solar energy

    International Nuclear Information System (INIS)

    The aim of this phase of the work is to study commercially available low priced catalysts, for the methanation and reforming processes in the closed-loop solar chemical heat pipe. This report summarized some long term tests of commercially available methanation catalysts and the measurement of their active surface before and after reaction. It was found that the 1%Ru on alumina stars catalysts (prepared by Englehard Company according to our request) is very active and stable at 350-750 C. The catalyst 'A' produced in Russia, is less active, however, did not lose the mechanical strength. The 50% Ni/SiO2 catalyst is active as the 'A' catalyst but loses its activity after treatment at temperature > 600 C, its geometrical size shrinked. (authors). 25 refs., 25 figs., 36 tabs

  19. The Influence of the Feed Protein and Energy Level on the Meat Chemical Composition at „Lohmann Meat” Hybrid

    Directory of Open Access Journals (Sweden)

    Adela Marcu

    2011-10-01

    Full Text Available In this paper was studied the influence of feed energy-protein level on meat chemical composition depending on sex and anatomical region for chicken broiler belonging „LOHMANN MEAT” hybrid, slaughtered at 42 days old. The two groups (control group-Lc and experimental groups-Lexp. were given feed mixed with different level of energy and protein (Lc-standard hybrid, Lexp.-higher by 10% compared to standard hybrid. After slaughter, from each group were sampled 10 carcasses (five females and five males, and from different portions of the carcass (breast, thighs and shanks, was determined the meat chemical composition (water, dry matter, protein, lipids and minerals using STAS methods. For males the pectoral muscle had a greater amount of dry matter, compared with females, the situation is reversed when has been referring to the muscles of the thighs and shanks. The proteins content in meat has presented variation depending on: sex (in males was registred big values comparative with females, anatomical region (in pectorals was registred maximum values and in thighs minimum values and nutrition (feed with energy and protein high level was determined incresed content the protein in meat. The lipids content in meat showed the biggest variation between muscles analyzed, with minimum values in the pectoral muscles (from 0.67 at males-Lexp. to 0,95% in females-Lc and maximum values in the upper thigh muscles (from 6.97% in males-Lexp. to 8,23% in females-Lc. The high quality value on meat has been at the Lexp. group, which in all cases had the highest protein content and lowest lipids content in muscles.

  20. Electronic torsional sound in linear atomic chains: chemical energy transport at 1000 km/s

    CERN Document Server

    Kurnosov, Arkady A; Maksymov, Andrii A; Burin, Alexander L

    2016-01-01

    We investigate entirely electronic torsional vibrational modes in linear cumulene chains. The carbon nuclei of a cumulene are positioned along the primary axis so they can participate only in transverse and longitudinal motions. However, the interatomic electronic clouds behave as a torsion spring with remarkable torsional stiffness. The collective dynamics of these clouds can be described in terms of electronic vibrational quanta, which we name torsitons. It is shown that the group velocity of the wavepacket of torsitons is much higher than the typical speed of sound, because of the small mass of participating electrons compared to the atomic mass. For the same reason the maximum energy of the torsitons in cumulenes is as high as a few electronvolts, while the minimum possible energy is evaluated as a few hundred wavenumbers and this minimum is associated with asymmetry of zero point atomic vibrations. Molecular systems for experimental evaluation of the predictions are proposed.

  1. A periodic energy decomposition analysis method for the investigation of chemical bonding in extended systems

    International Nuclear Information System (INIS)

    The development and first applications of a new periodic energy decomposition analysis (pEDA) scheme for extended systems based on the Kohn-Sham approach to density functional theory are described. The pEDA decomposes the bonding energy between two fragments (e.g., the adsorption energy of a molecule on a surface) into several well-defined terms: preparation, electrostatic, Pauli repulsion, and orbital relaxation energies. This is complemented by consideration of dispersion interactions via a pairwise scheme. One major extension toward a previous implementation [Philipsen and Baerends, J. Phys. Chem. B 110, 12470 (2006)] lies in the separate discussion of electrostatic and Pauli and the addition of a dispersion term. The pEDA presented here for an implementation based on atomic orbitals can handle restricted and unrestricted fragments for 0D to 3D systems considering periodic boundary conditions with and without the determination of fragment occupations. For the latter case, reciprocal space sampling is enabled. The new method gives comparable results to established schemes for molecular systems and shows good convergence with respect to the basis set (TZ2P), the integration accuracy, and k-space sampling. Four typical bonding scenarios for surface-adsorbate complexes were chosen to highlight the performance of the method representing insulating (CO on MgO(001)), metallic (H2 on M(001), M = Pd, Cu), and semiconducting (CO and C2H2 on Si(001)) substrates. These examples cover diverse substrates as well as bonding scenarios ranging from weakly interacting to covalent (shared electron and donor acceptor) bonding. The results presented lend confidence that the pEDA will be a powerful tool for the analysis of surface-adsorbate bonding in the future, enabling the transfer of concepts like ionic and covalent bonding, donor-acceptor interaction, steric repulsion, and others to extended systems

  2. Descriptions of surface chemical reactions using a neural network representation of the potential-energy surface

    Science.gov (United States)

    Lorenz, Sönke; Scheffler, Matthias; Gross, Axel

    2006-03-01

    A neural network (NN) approach is proposed for the representation of six-dimensional ab initio potential-energy surfaces (PES) for the dissociation of a diatomic molecule at surfaces. We report tests of NN representations that are fitted to six-dimensional analytical PESs for H2 dissociation on the clean and the sulfur covered Pd(100) surfaces. For the present study we use high-dimensional analytical PESs as the basis for the NN training, as this enables us to investigate the influence of phase space sampling on adsorption rates in great detail. We note, however, that these analytical PESs were obtained from detailed density functional theory calculations. When information about the PES is collected only from a few high-symmetric adsorption sites, we find that the obtained adsorption probabilities are not reliable. Thus, intermediate configurations need to be considered as well. However, it is not necessary to map out complete elbow plots above nonsymmetric sites. Our study suggests that only a few additional energies need to be considered in the region of activated systems where the molecular bond breaks. With this understanding, the required number of NN training energies for obtaining a high-quality PES that provides a reliable description of the dissociation and adsorption dynamics is orders of magnitude smaller than the number of total-energy calculations needed in traditional ab initio on the fly molecular dynamics. Our analysis also demonstrates the importance of a reliable, high-dimensional PES to describe reaction rates for dissociative adsorption of molecules at surfaces.

  3. Effect of dry oxidation on the energy gap and chemical composition of CVD graphene on nickel

    OpenAIRE

    Aria, Adrianus I.; Adi W. Gani; Gharib, Morteza

    2014-01-01

    The findings presented herein show that the electronic properties of CVD graphene on nickel can be altered from metallic to semiconducting by introducing oxygen adsorbates via UV/ozone or oxygen plasma treatment. These properties can be partially recovered by removing the oxygen adsorbates via vacuum annealing treatment. The effect of oxidation is studied by scanning tunneling microscopy/spectroscopy (STM/STS) and X-ray photoelectron spectroscopy (XPS). As probed by STM/STS, an energy gap ope...

  4. A periodic energy decomposition analysis method for the investigation of chemical bonding in extended systems

    Energy Technology Data Exchange (ETDEWEB)

    Raupach, Marc; Tonner, Ralf, E-mail: tonner@chemie.uni-marburg.de [Fachbereich Chemie, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35032 Marburg (Germany)

    2015-05-21

    The development and first applications of a new periodic energy decomposition analysis (pEDA) scheme for extended systems based on the Kohn-Sham approach to density functional theory are described. The pEDA decomposes the bonding energy between two fragments (e.g., the adsorption energy of a molecule on a surface) into several well-defined terms: preparation, electrostatic, Pauli repulsion, and orbital relaxation energies. This is complemented by consideration of dispersion interactions via a pairwise scheme. One major extension toward a previous implementation [Philipsen and Baerends, J. Phys. Chem. B 110, 12470 (2006)] lies in the separate discussion of electrostatic and Pauli and the addition of a dispersion term. The pEDA presented here for an implementation based on atomic orbitals can handle restricted and unrestricted fragments for 0D to 3D systems considering periodic boundary conditions with and without the determination of fragment occupations. For the latter case, reciprocal space sampling is enabled. The new method gives comparable results to established schemes for molecular systems and shows good convergence with respect to the basis set (TZ2P), the integration accuracy, and k-space sampling. Four typical bonding scenarios for surface-adsorbate complexes were chosen to highlight the performance of the method representing insulating (CO on MgO(001)), metallic (H{sub 2} on M(001), M = Pd, Cu), and semiconducting (CO and C{sub 2}H{sub 2} on Si(001)) substrates. These examples cover diverse substrates as well as bonding scenarios ranging from weakly interacting to covalent (shared electron and donor acceptor) bonding. The results presented lend confidence that the pEDA will be a powerful tool for the analysis of surface-adsorbate bonding in the future, enabling the transfer of concepts like ionic and covalent bonding, donor-acceptor interaction, steric repulsion, and others to extended systems.

  5. Multiconfiguration molecular mechanics algorithm for potential energy surfaces of chemical reactions

    International Nuclear Information System (INIS)

    We present an efficient algorithm for generating semiglobal potential energy surfaces of reactive systems. The method takes as input molecular mechanics force fields for reactants and products and a quadratic expansion of the potential energy surface around a small number of geometries whose locations are determined by an iterative process. These Hessian expansions might come, for example, from ab initio electronic structure calculations, density functional theory, or semiempirical molecular orbital theory. A 2x2 electronic diabatic Hamiltonian matrix is constructed from these data such that, by construction, the lowest eigenvalue of this matrix provides a semiglobal approximation to the lowest electronically adiabatic potential energy surface. The theory is illustrated and tested by applications to rate constant calculations for three gas-phase test reactions, namely, the isomerization of 1,3-cis-pentadiene, OH+CH4→H2O+CH3, and CH2Cl+CH3F→CH3Cl+CH2F. (c) 2000 American Institute of Physics

  6. Fingerprints of energy dissipation for exothermic surface chemical reactions: O2 on Pd(100)

    Science.gov (United States)

    Bukas, Vanessa J.; Mitra, Shubhrajyoti; Meyer, Jörg; Reuter, Karsten

    2015-07-01

    We present first-principles calculations of the sticking coefficient of O2 at Pd(100) to assess the effect of phononic energy dissipation on this kinetic parameter. For this, we augment dynamical simulations on six-dimensional potential energy surfaces (PESs) representing the molecular degrees of freedom with various effective accounts of surface mobility. In comparison to the prevalent frozen-surface approach, energy dissipation is found to qualitatively affect the calculated sticking curves. At the level of a generalized Langevin oscillator model, we achieve good agreement with experimental data. The agreement is similarly reached for PESs based on two different semi-local density-functional theory functionals. This robustness of the simulated sticking curve does not extend to the underlying adsorption mechanism, which is predominantly directly dissociative for one functional or molecularly trapped for the other. Completely different adsorption mechanisms therewith lead to rather similar sticking curves that agree equally well with the experimental data. This highlights the danger of the prevalent practice to extract corresponding mechanistic details from simple fingerprints of measured sticking data for such exothermic surface reactions.

  7. Carbon, Energy and Water Footprint of threeAkzoNobel Internal Sizing Chemicals : A Cradle to Gate LCA related study

    OpenAIRE

    Triantou, Adamantia-Dimitra

    2009-01-01

    Functional chemicals are used in paper production to enhance specific characteristics in the final paper product. One functional chemicals category is internal sizing chemicals which are used to create liquid resistance hydrophobicity in the paper, at the wet end of the production process. This thesis report calculated the environmental burdens of three internal sizing chemicals produced by Eka Chemicals, a business unit of AkzoNobel. The three chemicals under study are a specific product of ...

  8. Prospects of the use of chemically reactive working media in solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Umarov, G.Ia.; Nesterenko, V.B.; Spivak, S.I.; Bubnov, V.P.; Umarov, A.G.

    1984-01-01

    The use of dissociating gases in solar and solar/fossil electric generating stations is shown to increase efficiency and to decrease cost. The advantages of gas and gas-liquid cycles with the heat transfer agent N2O4 as the working medium over both gas turbines using inert gases and steam turbines are presented. In the flow section of a high-pressure turbine of a gas-liquid cycle, high-pressure gas expands from 150 to 21 atm, and the gas temperature decreases from 450 to 300 C. Forty percent of the heat loss, transformed into useful turbine work, is formed due to the heat generated in the recombination of NO and O2. In the low-pressure turbine, 50 percent of the turbine work is formed in this way. The intensity of heat transfer processes in the chemically reactive system is 5-8 times higher than in air systems, and 3-4 times higher than in steam systems. 20 references.

  9. Effect of chemical heterogeneity of biodegradable polymers on surface energy: A static contact angle analysis of polyester model films.

    Science.gov (United States)

    Belibel, R; Avramoglou, T; Garcia, A; Barbaud, C; Mora, L

    2016-02-01

    Biodegradable and bioassimilable poly((R,S)-3,3 dimethylmalic acid) (PDMMLA) derivatives were synthesized and characterized in order to develop a new coating for coronary endoprosthesis enabling the reduction of restenosis. The PDMMLA was chemically modified to form different custom groups in its side chain. Three side groups were chosen: the hexyl group for its hydrophobic nature, the carboxylic acid and alcohol groups for their acid and neutral hydrophilic character, respectively. The sessile drop method was applied to characterize the wettability of biodegradable polymer film coatings. Surface energy and components were calculated. The van Oss approach helped reach not only the dispersive and polar acid-base components of surface energy but also acid and basic components. Surface topography was quantified by atomic force microscopy (AFM) and subnanometer average values of roughness (Ra) were obtained for all the analyzed surfaces. Thus, roughness was considered to have a negligible effect on wettability measurements. In contrast, heterogeneous surfaces had to be corrected by the Cassie-Baxter equation for copolymers (10/90, 20/80 and 30/70). The impact of this correction was quantified for all the wettability parameters. Very high relative corrections (%) were found, reaching 100% for energies and 30% for contact angles. PMID:26652458

  10. Comparisons of classical and Wigner sampling of transition state energy levels for quasiclassical trajectory chemical dynamics simulations

    International Nuclear Information System (INIS)

    Quasiclassical trajectory calculations are compared, with classical and Wigner sampling of transition state (TS) energy levels, for C2H5F≠→HF+C2H4 product energy partitioning and [Cl···CH3···Cl]- central barrier dynamics. The calculations with Wigner sampling are reported here for comparison with the previously reported calculations with classical sampling [Y. J. Cho et al., J. Chem. Phys. 96, 8275 (1992); L. Sun and W. L. Hase, J. Chem. Phys. 121, 8831 (2004)]. The C2H5F≠ calculations were performed with direct dynamics at the MP2/6-31G* level of theory. Classical and Wigner sampling give post-transition state dynamics, for these two chemical systems, which are the same within statistical uncertainties. This is a result of important equivalences in these two sampling methods for selecting initial conditions at a TS. In contrast, classical and Wigner sampling often give different photodissociation dynamics [R. Schinke, J. Phys. Chem. 92, 3195 (1988)]. Here the sampling is performed for a vibrational state of the ground electronic state potential energy surface (PES), which is then projected onto the excited electronic state's PES. Differences between the ground and the excited PESs may give rise to substantially different excitations of the vibrational and dissociative coordinates on the excited state PES by classical and Wigner sampling, resulting in different photodissociation dynamics.

  11. Thermal stability and energy harvesting characteristics of Au nanorods: harsh environment chemical sensing

    Science.gov (United States)

    Karker, Nicholas; Dharmalingam, Gnanaprakash; Carpenter, Michael A.

    2015-05-01

    Monitoring the levels of polluting gases such as CO and NOx from high temperature (500°C and higher) combustion environments requires materials with high thermal stability and resilience that can withstand harsh oxidizing and reducing environments. Au nanorods (AuNRs) have shown potential in plasmonic gas sensing due to their catalytic activity, high oxidation stability, and absorbance sensitivity to changes in the surrounding environment. By using electron beam lithography, AuNR geometries can be patterned with tight control of the rod dimensions and spacings, allowing tunability of their optical properties. Methods such as NR encapsulation within an yttria-stabilized zirconia overcoat layer with subsequent annealing procedures will be shown to improve temperature stability within a simulated harsh environment. Since light sources and spectrometers are typically required to obtain optical measurements, integration is a major barrier for harsh environment sensing. Plasmonic sensing results will be presented where thermal energy is harvested by the AuNRs, which replaces the need for an external incident light source. Results from gas sensing experiments that utilize thermal energy harvesting are in good agreement with experiments which use an external incident light source. Principal component analysis results demonstrate that by selecting the most "active" wavelengths in a plasmonic band, the wavelength space can be reduced from hundreds of monitored wavelengths to just four, without loss of information about selectivity of the AuNRs. By combining thermal stability, the thermal energy harvesting capability, and the selectivity in gas detection (achieved through multivariate analysis), integration of plasmonic sensors into combustion environments can be greatly simplified.

  12. Atomic Energy of Canada Limited-Chemical Company Annual review of operations, 1980-81

    International Nuclear Information System (INIS)

    Record production of heavy water was achieved: the plants at Glace Bay and Port Hawkesbury, Nova Scotia, produced a total of 560 megagrams. A shipment of 500 Mg was delivered on time to the Wolsung CANDU reactor in Korea. Energy conservation and waste heat utilization programs included the construction of a greenhouse at the Glace Bay site. Long-term protection of the La Prade site is essentially complete. The company has reorganized its marketing and engineering division and assumed a greater international role

  13. Compositions and chemical bonding in ceramics by quantitative electron energy-loss spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Bentley, J.; Horton, L.L. [Oak Ridge National Lab., TN (United States); McHargue, C.J. [Tennessee Univ., Knoxville, TN (United States); McKernan, S.; Carter, C.B. [Minnesota Univ., Minneapolis, MN (United States). Dept. of Chemical Engineering; Revcolevschi, A. [Univ. de Paris-Sud, Lab. de Chemie des Solides (France); Tanaka, S.; Davis, R.F. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Materials Science and Engineering

    1993-12-31

    Quantitative electron energy-loss spectrometry was applied to a range of ceramic materials at a spatial resolution of <5 nm. Analysis of Fe L{sub 23} white lines indicated a low-spin state with a charge transfer of {approximately}1.5 electrons/atom onto the Fe atoms implanted into (amorphized) silicon carbide. Gradients of 2 to 5% in the Co:O stoichiometry were measured across 100-nm-thick Co{sub 3}O{sub 4} layers in an oxidized directionally solidified CoO-ZrO{sub 2} eutectic, with the highest O levels near the ZrO{sub 2}. The energy-loss near-edge structures were dramatically different for the two cobalt oxides; those for CO{sub 3}O{sub 4} have been incorrectly ascribed to CoO in the published literature. Kinetically stabilized solid solubility occurred in an AlN-SiC film grown by low-temperature molecular beam epitaxy (MBE) on {alpha}(6H)-SiC, and no detectable interdiffusion occurred in couples of MBE-grown AlN on SiC following annealing at up to 1750C. In diffusion couples of polycrystalline AlN on SiC, interfacial 8H sialon (aluminum oxy-nitride) and pockets of Si{sub 3}N{sub 4}-rich {beta}{prime} sialon in the SiC were detected.

  14. Atomic-scale chemical imaging and quantification of metallic alloy structures by energy-dispersive X-ray spectroscopy.

    Science.gov (United States)

    Lu, Ping; Zhou, Lin; Kramer, M J; Smith, David J

    2014-01-01

    Determination of atomic-scale crystal structure for nanostructured intermetallic alloys, such as magnetic alloys containing Al, Ni, Co (alnico) and Fe, is crucial for understanding physical properties such as magnetism, but technically challenging due to the small interatomic distances and the similar atomic numbers. By applying energy-dispersive X-ray spectroscopy (EDS) mapping to the study of two intermetallic phases of an alnico alloy resulting from spinodal decomposition, we have determined atomic-scale chemical composition at individual lattice sites for the two phases: one is the B2 phase with Fe0.76Co0.24 -Fe0.40Co0.60 ordering and the other is the L2(1) phase with Ni0.48Co0.52 at A-sites, Al at B(Ι)-sites and Fe0.20Ti0.80 at B(ΙΙ)-sites, respectively. The technique developed through this study represents a powerful real-space approach to investigate structure chemically at the atomic scale for a wide range of materials systems. PMID:24492747

  15. Revision and extension of Eco-LCA metrics for sustainability assessment of the energy and chemical processes.

    Science.gov (United States)

    Yang, Shiying; Yang, Siyu; Kraslawski, Andrzej; Qian, Yu

    2013-12-17

    Ecologically based life cycle assessment (Eco-LCA) is an appealing approach for the evaluation of resources utilization and environmental impacts of the process industries from an ecological scale. However, the aggregated metrics of Eco-LCA suffer from some drawbacks: the environmental impact metric has limited applicability; the resource utilization metric ignores indirect consumption; the renewability metric fails to address the quantitative distinction of resources availability; the productivity metric seems self-contradictory. In this paper, the existing Eco-LCA metrics are revised and extended for sustainability assessment of the energy and chemical processes. A new Eco-LCA metrics system is proposed, including four independent dimensions: environmental impact, resource utilization, resource availability, and economic effectiveness. An illustrative example of comparing assessment between a gas boiler and a solar boiler process provides insight into the features of the proposed approach. PMID:24228888

  16. Evaluation of the potential for using old-field vegetation as an energy feedstock: Biomass yield, chemical composition, environmental concerns, and economics

    Energy Technology Data Exchange (ETDEWEB)

    Johnston, J.W. Jr.

    1990-07-01

    The major focus of current research on production of biomass for use as energy feedstock involves selection of species and genotypes best suited for specific regions of the United States and development of crop management techniques that maximize biomass productivity while minimizing environmental impacts and economic costs. The two experimental sites, and abandoned soybean field (AS) and an abandoned pasture (AP) were studied. At the AS site, the effects of two harvest frequencies (1 or 2 harvests annually), two nitrogen fertilizer treatments (1 or 2 harvests annually), two nitrogen fertilizer treatments (0 or 87 kg{center dot}ha{sup {minus}1}{center dot}yr{sup {minus}1}), and two phosphorous fertilizer treatments (0 or 111 kg{center dot}ha{sup {minus}1}{center dot}yr{sup {minus}1}) were determined. At the AP site, the effects of two harvest treatments (1 or 2 harvests annually), two fertilizer treatments (56:56:135 kg of N:P:K{center dot}ha{sup {minus}1}{center dot}yr{sup {minus}1}), and two lime treatments (0 or 4600 kg{center dot}ha{sup {minus}1}{center dot}yr{sup {minus}1}) were determined. At both sites, treatments were arranged in a randomized complete block 2 {times} 2 {times} 2 factorial experiment. The results of this research indicated that old-field vegetation is: (1) sufficiently productive to provide significant quantities of energy feedstock; (2) chemically suitable as an energy feedstock; (3) environmentally benign with respect to impacts related to soil erosion and nutrient depletion; (4) relatively unresponsive to fertilizer and lime inputs; and (5) economically competitive with other biomass energy feedstock candidates. 38 refs., 8 figs., 68 tabs.

  17. Energy analysis of two stage packed-bed chemical looping combustion configurations for integrated gasification combined cycles

    International Nuclear Information System (INIS)

    Chemical looping combustion is a promising technology for power production with integrated CO2 capture. High overall efficiencies can be reached, if the CLC reactors are operated at elevated pressures and high temperature, which can be accommodated in packed bed reactors. More possible oxygen carriers can be selected if the desired temperature rise for power production is achieved in a two stage chemical looping combustion (TS-CLC) process. In this work, the TS-CLC configuration using copper and manganese based oxygen carriers has been integrated in a complete power plant based on coal gasification (IG-CLC). An extensive energy analysis based on the combined use of a packed bed reactor modeling tool and a complete process simulation has been undertaken. An economic estimation of the reactors capital cost has also been carried out. From the material and energy balances the IG-CLC with one stage nickel-based CLC process results in a net electric efficiency of 41.1% on low heating value basis. In case of TS-CLC, efficiencies of 40.3%–40.8% have been obtained. This demonstrated that IGCC (integrated gasification combined cycles) adopting a TS-CLC process can also achieve high efficiency compared to conventional CO2 capture technologies. Although a larger reactor volume is required for TS-CLC, the total estimated investment costs are a factor two lower, because the oxygen carriers are much cheaper. - Highlights: • Complete IG-CLC power plants have been evaluated for different CLC configurations. • Novel operation strategy for the TS-CLC has been proposed: TS-CLC parallel. • The estimated capital costs of TS-CLC are a factor two smaller than one stage CLC. • The process efficiency of TS-CLC is demonstrated to be close to the one stage CLC

  18. Chemical bond effects on the low energy electronic stopping power: theory

    International Nuclear Information System (INIS)

    We discuss the applicability of a modified version of the Firsov model to account for the low-energy electronic stopping cross section (Se) due to molecular targets. We employ floating spherical Gaussian orbitals (FSGO), which reproduce major trends in electronic and geometrical structure of molecules. Two advantages of using FSGO are: i) each localized orbital is classified as inner shell, bonding and lone-pair species, hence a natural partitioning of Se from each type of orbital is possible and ii) a simple analytical expression for the orbital contribution to Se is obtained after averaging over all molecular orientations. Our results show an explicit dependence of Se on the geometric structure of the molecule as well as on the core and bond character. (orig.)

  19. The interplay between interface structure, energy level alignment and chemical bonding strength at organic-metal interfaces.

    Science.gov (United States)

    Willenbockel, M; Lüftner, D; Stadtmüller, B; Koller, G; Kumpf, C; Soubatch, S; Puschnig, P; Ramsey, M G; Tautz, F S

    2015-01-21

    What do energy level alignments at metal-organic interfaces reveal about the metal-molecule bonding strength? Is it permissible to take vertical adsorption heights as indicators of bonding strengths? In this paper we analyse 3,4,9,10-perylene-tetracarboxylic acid dianhydride (PTCDA) on the three canonical low index Ag surfaces to provide exemplary answers to these questions. Specifically, we employ angular resolved photoemission spectroscopy for a systematic study of the energy level alignments of the two uppermost frontier states in ordered monolayer phases of PTCDA. Data are analysed using the orbital tomography approach. This allows the unambiguous identification of the orbital character of these states, and also the discrimination between inequivalent species. Combining this experimental information with DFT calculations and the generic Newns-Anderson chemisorption model, we analyse the alignments of highest occupied and lowest unoccupied molecular orbitals (HOMO and LUMO) with respect to the vacuum levels of bare and molecule-covered surfaces. This reveals clear differences between the two frontier states. In particular, on all surfaces the LUMO is subject to considerable bond stabilization through the interaction between the molecular π-electron system and the metal, as a consequence of which it also becomes occupied. Moreover, we observe a larger bond stabilization for the more open surfaces. Most importantly, our analysis shows that both the orbital binding energies of the LUMO and the overall adsorption heights of the molecule are linked to the strength of the chemical interaction between the molecular π-electron system and the metal, in the sense that stronger bonding leads to shorter adsorption heights and larger orbital binding energies. PMID:25475998

  20. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Goethermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equiptment

    Energy Technology Data Exchange (ETDEWEB)

    Nancy Moller Weare

    2006-07-25

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  1. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Geothermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equipment

    International Nuclear Information System (INIS)

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  2. Low-energy and chemical-free activation of pyrolytic tire char and its adsorption characteristics.

    Science.gov (United States)

    Quek, Augustine; Balasubramanian, Rajasekhar

    2009-06-01

    It is generally known that the solid char obtained from pyrolysis of scrap rubber tires can be used as an adsorbent for several applications such as wastewater treatment. In this study, scrap tires were first pyrolyzed under nitrogen (N2) or carbon dioxide (CO2) gas under various temperatures to produce char. The char was activated in situ by post-pyrolysis oxygenation (PPO) at different temperature ranges as soon as the pyrolysis process was completed. Elemental and spectroscopic analyses showed significant zinc content in the char after PPO. Batch-mode removal of aqueous copper (Cu) using the chars revealed that, for N2 and CO2, the optimum condition for pyrolysis was at 550 degrees C and for activation was from 550 to 250 degrees C. Although CO2-pyrolyzed char had lower Cu and lead (Pb) removal than N2-pyrolyzed char, it had higher char yields. For both N2- and CO2-pyrolyzed char, activation with PPO improved their heavy metal removal efficiencies significantly compared with unactivated char. PPO chars had much faster removal rates and higher Cu removal compared with both pyrolyzed, unactivated char and commercial activated carbons. PMID:19603742

  3. Computational Investigations of Potential Energy Function Development for Metal--Organic Framework Simulations, Metal Carbenes, and Chemical Warfare Agents

    Science.gov (United States)

    Cioce, Christian R.

    Metal-Organic Frameworks (MOFs) are three-dimensional porous nanomaterials with a variety of applications, including catalysis, gas storage and separation, and sustainable energy. Their potential as air filtration systems is of interest for designer carbon capture materials. The chemical constituents (i.e. organic ligands) can be functionalized to create rationally designed CO2 sequestration platforms, for example. Hardware and software alike at the bleeding edge of supercomputing are utilized for designing first principles-based molecular models for the simulation of gas sorption in these frameworks. The classical potentials developed herein are named PHAST --- Potentials with High Accuracy, Speed, and Transferability, and thus are designed via a "bottom-up" approach. Specifically, models for N2 and CH4 are constructed and presented. Extensive verification and validation leads to insights and range of applicability. Through this experience, the PHAST models are improved upon further to be more applicable in heterogeneous environments. Given this, the models are applied to reproducing high level ab initio energies for gas sorption trajectories of helium atoms in a variety of rare-gas clusters, the geometries of which being representative of sorption-like environments commonly encountered in a porous nanomaterial. This work seeks to push forward the state of classical and first principles materials modeling. Additionally, the characterization of a new type of tunable radical metal---carbene is presented. Here, a cobalt(II)---porphyrin complex, [Co(Por)], was investigated to understand its role as an effective catalyst in stereoselective cyclopropanation of a diazoacetate reagent. Density functional theory along with natural bond order analysis and charge decomposition analysis gave insight into the electronics of the catalytic intermediate. The bonding pattern unveiled a new class of radical metal---carbene complex, with a doublet cobalt into which a triplet carbene

  4. Mixed Inhibition of Adenosine Deaminase Activity by 1,3-Dinitrobenzene: A Model for Understanding Cell-Selective Neurotoxicity in Chemically-Induced Energy Deprivation Syndromes in Brain

    OpenAIRE

    Wang, Yipei; Liu, Xin; Schneider, Brandon; Zverina, Elaina A.; Russ, Kristen; Wijeyesakere, Sanjeeva J.; Fierke, Carol A.; Richardson., Rudy J.; Philbert, Martin A.

    2011-01-01

    Astrocytes are acutely sensitive to 1,3-dinitrobenzene (1,3-DNB) while adjacent neurons are relatively unaffected, consistent with other chemically-induced energy deprivation syndromes. Previous studies have investigated the role of astrocytes in protecting neurons from hypoxia and chemical injury via adenosine release. Adenosine is considered neuroprotective, but it is rapidly removed by extracellular deaminases such as adenosine deaminase (ADA). The present study tested the hypothesis that ...

  5. Getting nanometric MoO{sub 3} through chemical synthesis and high energy milling

    Energy Technology Data Exchange (ETDEWEB)

    Santos-Beltrán, M. [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico); Paraguay-Delgado, F., E-mail: francisco.paraguay@cimav.edu.mx [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico); Santos-Beltrán, A. [Universidad Tecnológica de Chihuahua Sur, Km. 3 Carretera Chihuahua a Aldama s/n, C.P. 31050 Chihuahua, Chih. (Mexico); Fuentes, L. [Centro de Investigación en Materiales Avanzados (CIMAV), Laboratorio Nacional de Nanotecnología, Miguel de Cervantes No. 120, C.P. 31136 Chihuahua, Chih. (Mexico)

    2015-11-05

    The effects of high energy mechanical milling (HEMM) were studied on the microstructure and optical properties of MoO{sub 3} for hexagonal and orthorhombic phases. Employing HEMM was possible change particle size as a function of mechanical milling time, as well as the small quantity transformation percentage from hexagonal to orthorhombic phase. The relationship between microstrain and optical properties generated was studied. The electronic structures were calculated using the Density Functional Theory (DFT); to determinate partial density of state (PDOS). Band gap structure calculations show a good correlation between experimental and simulated data. The approximated values of microstrain, particle size, lattice parameters and oxygen vacancies were obtained employing the Rietveld refinement of X-ray diffraction patterns. Samples were characterized by electron microscopy techniques, surface area analysis (BET), thermal-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and ultraviolet–visible spectroscopy (UV–Vis). It was possible, obtain particles with size below 40 nm by 30 min milling. - Graphical abstract: Orthorhombic phase, SEM image, SAED before milling, milling NPs, Particle size and band gap variation by milling time. - Highlights: • MoO{sub 3} with hexagonal and orthorhombic structures was synthesized selectively. • By milling short time (30 m), it was possible get 40 nm diameter particles. • The band gap decrease for nanoparticles, then corroborated by simulation. • MoO{sub 3} nanoparticles get high surface area for new technologic applications.

  6. Getting nanometric MoO3 through chemical synthesis and high energy milling

    International Nuclear Information System (INIS)

    The effects of high energy mechanical milling (HEMM) were studied on the microstructure and optical properties of MoO3 for hexagonal and orthorhombic phases. Employing HEMM was possible change particle size as a function of mechanical milling time, as well as the small quantity transformation percentage from hexagonal to orthorhombic phase. The relationship between microstrain and optical properties generated was studied. The electronic structures were calculated using the Density Functional Theory (DFT); to determinate partial density of state (PDOS). Band gap structure calculations show a good correlation between experimental and simulated data. The approximated values of microstrain, particle size, lattice parameters and oxygen vacancies were obtained employing the Rietveld refinement of X-ray diffraction patterns. Samples were characterized by electron microscopy techniques, surface area analysis (BET), thermal-gravimetric analysis (TGA), differential scanning calorimetry (DSC) and ultraviolet–visible spectroscopy (UV–Vis). It was possible, obtain particles with size below 40 nm by 30 min milling. - Graphical abstract: Orthorhombic phase, SEM image, SAED before milling, milling NPs, Particle size and band gap variation by milling time. - Highlights: • MoO3 with hexagonal and orthorhombic structures was synthesized selectively. • By milling short time (30 m), it was possible get 40 nm diameter particles. • The band gap decrease for nanoparticles, then corroborated by simulation. • MoO3 nanoparticles get high surface area for new technologic applications

  7. The influence of chemical and color quenching on the shape of energy spectrum for Beta particles of 90Sr- 90Y by using liquid scintillation cocktail

    International Nuclear Information System (INIS)

    The effect of chemical quenching on the pulse height spectrum and Emax of Strontium 90Sr were studied using the organic scintillation cocktail and observing change in florescent yield and spectral shape (energy spectrum) of beta particles of 90Sr isotope in determining a relationship between the magnitude of material that causes quenching and the position of energy spectrum and Emax, adding 3 M nitric acid (HNO3) as chemical quencher to the scintillation, and added aqueous soluble yellow food dye with different concentration as color quencher. The beta detection efficiency depends on energy, spectral shape and cocktail. Typically, beta particles with maximum energies (Emax > 0.250 MeV) are detected with > 90% counting efficiency in organic liquid scintillation, where 90Sr has maximum beta energy, Emax, of 0.546 MeV and half-life of 28.17 years. The results were compared with reference and literature values. (author)

  8. XIX Mendeleev Congress on general and applied chemistry. Abstract book in 4 volumes. Volume 4. Chemistry aspects of modern energy and alternative energy resources. Chemistry of fossil and renewable hydrocarbon raw materials. Analytical chemistry: novel methods and devices for chemical research and analysis. Chemical education

    International Nuclear Information System (INIS)

    The abstracts of the XIX Mendeleev Congress on general and applied chemistry held 25-30 September 2011 in Volgograd are presented. The program includes the Congress plenary and section reports, poster presentations, symposia and round tables on key areas of chemical science and technology, and chemical education. The work of the Congress was held the following sections: 1. Fundamental problems of chemical sciences; 2. Chemistry and technology of materials, including nanomaterials; 3. Physicochemical basis of metallurgical processes; 4. Current issues of chemical production, technical risk assessment; 5. Chemical aspects of modern power and alternative energy sources; 6. Chemistry of fossil and renewable hydrocarbons; 7. Analytical chemistry: new methods and instruments for chemical research and analysis; 8. Chemical education. Volume 4 includes abstracts of oral and poster presentations and presentations of correspondent participants of the sections: Chemistry aspects of modern energy and alternative energy resources; Chemistry of fossil and renewable hydrocarbon raw materials; Analytical chemistry: novel methods and devices for chemical research and analysis; Chemical education, and author index

  9. Thickness-Dependent Binding Energy Shift in Few-Layer MoS2 Grown by Chemical Vapor Deposition.

    Science.gov (United States)

    Lin, Yu-Kai; Chen, Ruei-San; Chou, Tsu-Chin; Lee, Yi-Hsin; Chen, Yang-Fang; Chen, Kuei-Hsien; Chen, Li-Chyong

    2016-08-31

    The thickness-dependent surface states of MoS2 thin films grown by the chemical vapor deposition process on the SiO2-Si substrates are investigated by X-ray photoelectron spectroscopy. Raman and high-resolution transmission electron microscopy suggest the thicknesses of MoS2 films to be ranging from 3 to 10 layers. Both the core levels and valence band edges of MoS2 shift downward ∼0.2 eV as the film thickness increases, which can be ascribed to the Fermi level variations resulting from the surface states and bulk defects. Grainy features observed from the atomic force microscopy topographies, and sulfur-vacancy-induced defect states illustrated at the valence band spectra imply the generation of surface states that causes the downward band bending at the n-type MoS2 surface. Bulk defects in thick MoS2 may also influence the Fermi level oppositely compared to the surface states. When Au contacts with our MoS2 thin films, the Fermi level downshifts and the binding energy reduces due to the hole-doping characteristics of Au and easy charge transfer from the surface defect sites of MoS2. The shift of the onset potentials in hydrogen evolution reaction and the evolution of charge-transfer resistances extracted from the impedance measurement also indicate the Fermi level varies with MoS2 film thickness. The tunable Fermi level and the high chemical stability make our MoS2 a potential catalyst. The observed thickness-dependent properties can also be applied to other transition-metal dichalcogenides (TMDs), and facilitates the development in the low-dimensional electronic devices and catalysts. PMID:27488185

  10. Chemical Industry Bandwidth Study

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2006-12-01

    The Chemical Bandwidth Study provides a snapshot of potentially recoverable energy losses during chemical manufacturing. The advantage of this study is the use of "exergy" analysis as a tool for pinpointing inefficiencies.

  11. Using Edge-Preserving Algorithm with Non-local Mean for Significantly Improved Image-Domain Material Decomposition in Dual Energy CT

    CERN Document Server

    Zhao, Wei; Xing, Lei; Xie, Yaoqin; Xiong, Guanglei; Elmore, Kimberly; Zhu, Jun; Wang, Luyao; Min, James K

    2016-01-01

    Increased noise is a general concern for dual-energy material decomposition. Here, we develop an image-domain material decomposition algorithm for dual-energy CT (DECT) by incorporating an edge-preserving filter into the Local HighlY constrained backPRojection Reconstruction (HYPR-LR) framework. With effective use of the non-local mean, the proposed algorithm, which is referred to as HYPR-NLM, reduces the noise in dual energy decomposition while preserving the accuracy of quantitative measurement and spatial resolution of the material-specific dual energy images. We demonstrate the noise reduction and resolution preservation of the algorithm with iodine concentrate numerical phantom by comparing the HYPR-NLM algorithm to the direct matrix inversion, HYPR-LR and iterative image-domain material decomposition (Iter-DECT). We also show the superior performance of the HYPR-NLM over the existing methods by using two sets of cardiac perfusing imaging data. The reference drawn from the comparison study includes: (1) ...

  12. Evaluating Chemical Dispersant Efficacy In An Experimental Wave Tank: 1, Dispersant Effectiveness As A Function Of Energy Dissipation Rate

    Science.gov (United States)

    Numerous laboratory test systems have been developed for the comparison of efficacy between various chemical oil dispersant formulations. However, for the assessment of chemical dispersant effectiveness under realistic sea state, test protocols are required to produce hydrodynam...

  13. Chemical Composition, In vivo Digestibility and Metabolizable Energy Values of Caramba (Lolium multiflorum cv. caramba) Fresh, Silage and Hay.

    Science.gov (United States)

    Özelçam, H; Kırkpınar, F; Tan, K

    2015-10-01

    The experiment was conducted to determine nutritive values of caramba (Lolium multiflorum cv. caramba) fresh, silage and hay by in vivo and in vitro methods. There was a statistically significant difference (psilage (8.91%) and hay (6.35%). According to results of experiment, the crude fiber, neutral detergent fiber, acid detergent fiber (ADF), acid detergent lignin contents of the three forms of caramba varied between 30.22% to 35.06%, 57.41% to 63.70%, 35.32% to 43.29%, and 5.55% to 8.86% respectively. There were no significant differences between the three forms of caramba in digestibility of nutrients and in vivo metabolizable energy (ME) values (p>0.05). However, the highest MECN (ME was estimated using crude nutrients) and MEADF values were found in fresh caramba (psilage or hay is a good alternative source of forage for ruminants. PMID:26323399

  14. Non-Friedmann cosmology for the Local Universe, significance of the universal Hubble constant and short-distance indicators of dark energy

    OpenAIRE

    Chernin, Arthur D.; Teerikorpi, Pekka; Baryshev, Yurij V.

    2006-01-01

    Basing on the increasing evidence for the cosmological relevance of the local Hubble flow, we consider a simple analytical cosmological model for the Local Universe. This is a non-Friedmann model with a non-uniform static space-time. The major dynamical factor controlling the local expansion is the antigravity produced by the omnipresent and permanent dark energy of the cosmic vacuum (or the cosmological constant). The antigravity dominates at distances larger than 1-2 Mpc from the center of ...

  15. Low Cost Chemical Feedstocks Using an Improved and Energy Efficient Natural Gas Liquid (NGL) Removal Process, Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Howard, S.; Lu, Yingzhong

    2012-08-10

    The overall objective of this project is to develop a new low-cost and energy efficient Natural Gas Liquid (NGL) recovery process - through a combination of theoretical, bench-scale and pilot-scale testing - so that it could be offered to the natural gas industry for commercialization. The new process, known as the IROA process, is based on U.S. patent No. 6,553,784, which if commercialized, has the potential of achieving substantial energy savings compared to currently used cryogenic technology. When successfully developed, this technology will benefit the petrochemical industry, which uses NGL as feedstocks, and will also benefit other chemical industries that utilize gas-liquid separation and distillation under similar operating conditions. Specific goals and objectives of the overall program include: (i) collecting relevant physical property and Vapor Liquid Equilibrium (VLE) data for the design and evaluation of the new technology, (ii) solving critical R&D issues including the identification of suitable dehydration and NGL absorbing solvents, inhibiting corrosion, and specifying proper packing structure and materials, (iii) designing, construction and operation of bench and pilot-scale units to verify design performance, (iv) computer simulation of the process using commercial software simulation platforms such as Aspen-Plus and HYSYS, and (v) preparation of a commercialization plan and identification of industrial partners that are interested in utilizing the new technology. NGL is a collective term for C2+ hydrocarbons present in the natural gas. Historically, the commercial value of the separated NGL components has been greater than the thermal value of these liquids in the gas. The revenue derived from extracting NGLs is crucial to ensuring the overall profitability of the domestic natural gas production industry and therefore of ensuring a secure and reliable supply in the 48 contiguous states. However, rising natural gas prices have dramatically reduced

  16. A biological/chemical process for reduced waste and energy consumption, Caprolactam production: Phase 1, Select microorganisms and demonstrate feasibility. Final report

    Energy Technology Data Exchange (ETDEWEB)

    St.Martin, E.J.

    1995-08-01

    A novel biological/chemical process for converting cyclohexane into caprolactam was investigated. Microorganisms in a bioreactor would be used to convert cyclohexane into caprolactone followed by chemical synthesis of caprolactam using ammonia. The proposed bioprocess would be more energy efficient and reduce byproducts and wastes that are generated by the current chemical process. We have been successful in isolating from natural soil and water samples two microorganisms that can utilize cyclohexane as a sole source of carbon and energy for growth. These microorganisms were shown to have the correct metabolic intermediates and enzymes to convert cyclohexane into cyclohexanol, cyclohexanone and caprolactone. Genetic techniques to create and select for caprolactone hydrolase negative-mutants are being developed. These blocked-mutants will be used to convert cyclohexane into caprolactone but, because of the block, be unable to metabolize the caprolactone further and excrete it as a final end product.

  17. Chemical Industry Energy Saving and Emission Reduction Management%化工企业的节能减排管理

    Institute of Scientific and Technical Information of China (English)

    汪洋; 李文金; 杜建东

    2015-01-01

    The energy saving and emission reduction management should be a long-term strategic goals for chemical industry. Enterprise should encourage all the staffs participating actively in this management through internal promotion, training and variety of incentives. Through mass equilibrium analysis and cost analysis, the optimized direction and solve the emission issue from source could be fixed. By increasing automation controlling, the plant could also run more stability and reliability without more safety and environment incident happened. During the plant running and maintenance, we should continue to tap the potential benefits, standardize production management and catch all the details in order to do well for the energy saving and emission reduction management.%企业要做好节能减排管理,必须将其作为长期的战略目标,加强企业内部的宣传和培训,通过多种激励机制鼓励员工积极参与到节能减排管理中。生产装置要从源头进行节能减排,通过平衡分析和成本分析等手段,明确优化方向,通过提高装置运行的自动化程序,提高运行的稳定性和可靠性。在装置运行及停车检修过程中,不断挖掘潜在效益,规范生产管理,在细节上做好节能减排管理。

  18. Chemical Transport and Reduced-Form Models for Assessing Air Quality Impacts of Current and Future Energy Scenarios

    Science.gov (United States)

    Adams, P. J.

    2015-12-01

    Though essential for informed decision-making, it is challenging to estimate the air quality and public health impacts associated with current and future energy generation scenarios because the analysis must address the complicated atmospheric processes that air pollutants undergo: emissions, dispersion, chemistry, and removal. Employing a chemical transport model (CTM) is the most rigorous way to address these atmospheric processes. However, CTMs are expensive from a computational standpoint and, therefore, beyond the reach of policy analysis for many types of problems. On the other hand, previously available reduced-form models used for policy analysis fall short of the rigor of CTMs and may lead to biased results. To address this gap, we developed the Estimating Air pollution Social Impacts Using Regression (EASIUR) method, which builds parameterizations that predict per-tonne social costs and intake fractions for pollutants emitted from any location in the United States. Derived from a large database of tagged CTM simulations, the EASIUR method predicts social costs almost indistinguishable from a full CTM but with negligible computational requirements. We found that the average mortality-related social costs from inorganic PM2.5 and its precursors in the United States are 150,000-180,000/t EC, 21,000-34,000/t SO2, 4,200-15,000/t NOx, and 29,000-85,000/t NH3. This talk will demonstrate examples of using both CTMs and reduced-form models for assessing air quality impacts associated with current energy production activities as well as a future deployment of carbon capture and sequestration.

  19. U.S. Department of Energy Workers' mental models of radiation and chemical hazards in the workplace

    International Nuclear Information System (INIS)

    A pilot study was performed to test the mental models methodology regarding knowledge and perceptions of U.S. Department of Energy contractor radiation workers about ionizing radiation and hazardous chemicals. The mental models methodology establishes a target population's beliefs about risks and compares them with current scientific knowledge. The ultimate intent is to develop risk communication guidelines that address information gaps or misperceptions that could affect decisions and behavior. In this study, 15 radiation workers from the Hanford Site in Washington State were interviewed about radiation exposure processes and effects. Their beliefs were mapped onto a science model of the same topics to see where differences occurred. In general, workers' mental models covered many of the high-level parts of the science model but did not have the same level of detail. The following concepts appeared to be well understood by most interviewees: types, form, and properties of workplace radiation; administrative and physical controls to reduce radiation exposure risk; and the relationship of dose and effects. However, several concepts were rarely mentioned by most interviewees, indicating potential gaps in worker understanding. Most workers did not discuss the wide range of measures for neutralizing or decontaminating individuals following internal contamination. Few noted specific ways of measuring dose or factors that affect dose. Few mentioned the range of possible effects, including genetic effects, birth defects, or high dose effects. Variables that influence potential effects were rarely discussed. Workers rarely mentioned how basic radiation principles influenced the source, type, or mitigation of radiation risk in the workplace

  20. Effects of low-energy electron bombardment on the surface chemical structure and adhesive properties of polytetrafluoroethylene (PTFE)

    International Nuclear Information System (INIS)

    The x-ray photoemission studies of polytetrafluoroethylene (PTFE) bombarded by low-energy electrons in ultra-high vacuum conditions indicate that the major chemical changes induced by electron bombardment are defluorination of the surface and cross-linking of the polymer chains. The same electron bombardment process, when performed in the presence of 1 x 10-6 Torr ND3, also results in the adsorption of nitrogen-containing groups at the surface. The rate of nitrogen adsorption is linear for short electron bombardment times while the rates of defluorination and cross-linking are roughly exponential. However, at long bombardment times, the rates of nitrogen uptake, defluorination, and cross-linking become zero at the same time, indicating that defluorination of the surface is the rate-determining step in electron beam-induced adsorption of nitrogen-containing species. Regardless of whether the bombardment is carried out in ultra-high vacuum or in the presence of ND3, the maximum modification depth is less than 30 A. Pull tests performed on PTFE samples bombarded by electrons in ultra-high vacuum, then removed into air and bonded to epoxy show epoxy-PTFE joint strengths of 280--360 1b/in.2 (psi), are compared to zero psi for untreated PTFE and ≅2000 psi for cohesive failure within the PTFE layer

  1. Characterisation of the Thermal and Chemical Effects of Energetic Materials not Likely to Detonate

    OpenAIRE

    Biteau, Hubert; Marlair, Guy; Drysdale, Dougal; Torero, Jose L.

    2006-01-01

    Energetic materials encompass a wide range of chemical compounds all associated with a significant risk of fire and explosion. They include explosives, pyrotechnic materials, powders, fertilizers and other unsteady chemicals. These materials store a high level of chemical energy and are able to release it rapidly without external contribution of oxygen or other oxidizer. The aim of this work is the analysis of thermal and chemical characteristics of energy-rich materials under conditions t...

  2. Energy exploitation of acid gas with high H2S content by means of a chemical looping combustion system

    International Nuclear Information System (INIS)

    Highlights: • CLC can exploit the energy potential of acid gas by burning H2S. • New combustion process demonstration in a continuous CLC unit. • Highest H2S concentrations (20 vol.%) ever used in a CLC process. • Fe20γAl oxygen carrier is a suitable material for acid gas combustion. • H2S content above 20 vol.% turns the acid gas CLC into an auto-thermal process. - Abstract: In gas and petroleum industry, the waste gas stream from the sweetening process of a sour natural gas stream is commonly referred as acid gas. Chemical Looping Combustion (CLC) technology has the potential to exploit the combustible fraction of acid gas, H2S, to produce energy obtaining a flue gas highly concentrated on CO2 and SO2, which can be cost-effectively separated for subsequent applications, such as sulfuric acid production. At the same time, a concentrated CO2 stream ready for storage is obtained. The resistance of oxygen carriers to sulfur becomes crucial when an acid gas is subjected to a CLC process since the H2S content can be very high. In this work, a total of 41 h of continuous operation with acid gas and H2S concentrations up to 20 vol.% has been carried out in a 500 Wth CLC unit with two oxygen carriers based on Cu (Cu14γAl) and Fe (Fe20γAl). The formation of copper sulfides and the SO2 emissions in the air reactor made the Cu14γAl material not adequate for the process. In contrast, excellent results were obtained during acid gas combustion with the Fe20γAl oxygen carrier. H2S was fully burnt to SO2 in the fuel reactor at all operating conditions, SO2 was never detected in the gas outlet stream of the air reactor, and iron sulfides were never formed even at H2S concentrations as high as 20 vol.%. Furthermore, it was found that a H2S content of 20 vol.% in the acid gas was high enough to turn the CLC process into an auto-thermal process. Based on these results, it can be concluded that the Fe-based materials prepared by impregnation are very adequate to exploit

  3. Integration of Biological, Physical/Chemical and Energy Efficient Systems in the CELSS Antarctic Analog: Performance of Prototype Systems and Issues for Life Support

    Science.gov (United States)

    Bubenheim, David L.; Flynn, Michael T.; Lamparter, Richard; Bates, Maynard; Kliss, Mark (Technical Monitor)

    1998-01-01

    The Controlled Ecological Life Support System (CELSS) Antarctic Analog Project (CAAP) is a joint endeavor between the National Science Foundation, Office of Polar Programs (NSF-OPP), and the National Aeronautics and Space Administration (NASA). The fundamental objective is to develop, deploy, and operate a testbed of advanced life support technologies at the Amundsen-Scott South Pole Station that enable the objectives of both the NSF and NASA. The functions of food production, water purification, and waste treatment, recycle, and reduction provided by CAAP will improve the quality of life for the South Pole inhabitants, reduce logistics dependence, enhance safety, and minimize environmental impacts associated with human presence on the polar plateau. Because of the analogous technical, scientific, and mission features with Planetary missions, such as a mission to Mars, CAAP provides NASA with a method for validating technologies and overall approaches to supporting humans. Prototype systems for waste treatment, water recycle, resource recovery and crop production are being evaluated in a testbed at Ames Research Center. The combined performance of these biological and physical/chemical systems as an integrated function in support of the human habitat will be discussed. Overall system performance will be emphasized. The effectiveness and efficiency of component technologies will be discussed in the context of energy and mass flow within the system and contribution to achieving a mass and energy conservative system. Critical to the discussion are interfaces with habitat functions outside of the closed-loop life support: the ability of the system to satisfy the life support requirements of the habitat and the ability to define input requirements. The significance of analog functions in relation to future Mars habitats will be discussed.

  4. Dualistic Chemical Evolution to the Stabilization of the Energy-Balance: A Hypothesis on the Origin of Life on the Earth

    OpenAIRE

    Matsuda, Genji

    2004-01-01

    A hypothesis of the dualistic chemical evolution to the stabilization of the energy-balance is proposed and explained in connection with the origin of life on the earth. From author's viewpoint, the existence of all things and all phenomena in the universe are closely related to the stabilization of the energy-balance and life is not an exceptional case in this matter. It is presumed that the first life on the earth was formed as the process towards the stabilization of the energy-balance by ...

  5. Triboelectric nanogenerators as new energy technology for self-powered systems and as active mechanical and chemical sensors.

    Science.gov (United States)

    Wang, Zhong Lin

    2013-11-26

    series, from polymer to metal and to fabric, the morphologies of their surfaces can be modified by physical techniques with the creation of pyramid-, square-, or hemisphere-based micro- or nanopatterns, which are effective for enhancing the contact area and possibly the triboelectrification. The surfaces of the materials can be functionalized chemically using various molecules, nanotubes, nanowires, or nanoparticles, in order to enhance the triboelectric effect. The contact materials can be composites, such as embedding nanoparticles in a polymer matrix, which may change not only the surface electrification but also the permittivity of the materials so that they can be effective for electrostatic induction. Therefore, there are numerous ways to enhance the performance of the TENG from the materials point of view. This gives an excellent opportunity for chemists and materials scientists to do extensive study both in the basic science and in practical applications. We anticipate that a better enhancement of the output power density will be achieved in the next few years. The TENG is possible not only for self-powered portable electronics but also as a new energy technology with potential to contribute to the world energy in the near future. PMID:24079963

  6. U.S. contribution of section A.3. The significance of long-term supply and energy sufficiency prospects offered by fast breeders

    International Nuclear Information System (INIS)

    Costs involved in breeder deployment are identified and analyzed, i.e., high breeder capital costs, fuel cycle costs, research and development costs and discount rates. It is pointed out that while there are potential benefits to be derived from future application of fast breeders, there are also significant costs and other factors requiring consideration. Careful country-specific analyses are needed. Such analyses may conclude for example that although breeders could become economical in less highly industrialized nations, such nations may find it more economical and practical to purchase reprocessing services from existing large commercial size plants rather than deploy their own small scale reprocessing plants

  7. Chemical spectroscopy

    International Nuclear Information System (INIS)

    The purpose of chemical spectroscopy with neutrons is to utilize the dependence of neutron scattering cross-sections on isotope and on momentum transfer (which probes the spatial extent of the excitation) to understand fundamental and applied aspects of the dynamics of molecules and fluids. Chemical spectroscopy is divided into three energy ranges: vibrational spectroscopy, 25-500 MeV, for which much of the work is done on Be-filter analyzer instruments; low energy spectroscopy, less than 25 MeV; and high resolution spectroscopy, less than 1 MeV, which typically is performed on backscattering spectrometers. Representative examples of measurements of the Q-depenence of vibrational spectra, higher energy resolution as well as extension of the Q-range to lower values at high energy transfers, and provisions of higher sensitivities in vibrational spectroscopy are discussed. High resolution, high sensitivity, and polarization analysis studies in low energy spectroscopy are discussed. Applications of very high resolution spectroscopy are also discussed

  8. Review and analysis of Japan's efforts to ensure nuclear non-proliferation. Significant elements in terms of winning trust for the peaceful nature of the nuclear energy use and future challenges

    International Nuclear Information System (INIS)

    Japan initiated a program of peaceful use of nuclear energy in 1950s. Since that time, Japan has made it clear that the program is carried out strictly for peaceful purposes in a transparent manner, implementing measures to win trust from international community. In this report, we review, analyze and evaluate Japan's efforts to ensure nuclear non-proliferation, dividing them into seven categories, namely, (a) legislative measures to ensure peaceful use of nuclear energy, (b) commitments and cooperation for international nuclear non-proliferation regime, (c) safeguards, (d) efforts to secure transparency of peaceful use of nuclear energy, (e) measures to ensure nuclear nonproliferation in sensitive nuclear facilities, (f) export control and control of sensitive nuclear technology and (g) physical protection and nuclear security. Through such review, analysis and evaluation, the significant elements in terms of wining the trust for the peaceful nature of the nuclear energy use and future challenges have been identified for each category stated above. We expect this report to contribute to the discussion on the policy of peaceful use of nuclear energy and nuclear non-proliferation within the Atomic Energy Commission of Japan and to be any use for the states which plan to initiate nuclear energy use program on a significant scale including the deployment of nuclear power plants. (author)

  9. Skeletal lesions in the broiler, with special reference to dyschondroplasia (osteochondrosis). Pathology, frequency and clinical significance in two strains of birds on high and low energy feed.

    Science.gov (United States)

    Poulos, P W; Reiland, S; Elwinger, K; Olsson, S E

    1978-01-01

    The material consisted of 2,950 broilers of the variety Hybro Compact of two lines. An equal number of birds of both lines were given either a high energy feed (H) or a low energy feed (L), containing all nutrients known to be required by broilers. During the first 3 weeks, H and L starter feeds were given and thereafter H and L finishing feeds. At 21, 35, and 45 days of age, the birds were weighed in groups, and feed conversion calculated. At 21 days of age, the frequency of crooked toes and swollen hocks was registered. Birds were taken from each group for necropsy at regular intervals. Both clinically normal birds and those with locomotor disturbances were selected for necropsy, including radiographic examination. With the exception of 240 birds, which were kept for a long-term study, the birds on the H feed were slaughtered at 42 days of age and the ones on the L feed at 49 days of age. The long-term birds were slaughtered at regular intervals, weighed, and necropsied. The last birds were slaughtered at 134 days of age. A large number of skeletal lesions were found. They were: Twisted legs, slipped tendons, crooked toes, bowing of the proximal tibia, dyschondroplasia at different sites, fracture of the fibula, deformity of the spine, deviated sternum (with breast blisters), arthritis, and osteomyelitis. Leg weakness was found to be almost synonymous with skeletal deformities. Other causes were rare. The normal development and morphology of the skeleton and the morphology of tibial dyschondroplasia were the same as those previously described in the turkey. Dyschondroplasia was found not only in the proximal tibia but also in the distal tibia, proximal tarsometatarsus, proximal and distal femur, and to some extent also in the costochondral junction. Tibial dyschondroplasia was more common in the birds on the H feed than in the birds on the L feed. Hence, tibial dyschondroplasia was correlated with rapid growth. The other skeletal lesions did not differ in

  10. Energy Technology Programs: program summaries for 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-12-01

    The Energy Technology Programs in the BNL Department of Energy and Environment cover a broad range of activities, namely: electrochemical research, chemical energy storage, chemical heat pumps, solar technology, fossil technology, catalytic systems development, space-conditioning technology, and technical support/program management. Summaries of the individual tasks associated with these activities along with publications, significant accomplishments, and program funding levels are presented.

  11. Chemical Bonding of AlH3 Hydride by Al-L2,3 Electron Energy-Loss Spectra and First-Principles Calculations

    OpenAIRE

    Kazutaka Ikeda; Shin-Ichi Orimo; Kazuyoshi Tatsumi; Shunsuke Muto

    2012-01-01

    In a previous study, we used transmission electron microscopy and electron energy-loss (EEL) spectroscopy to investigate dehydrogenation of AlH3 particles. In the present study, we systematically examine differences in the chemical bonding states of Al-containing compounds (including AlH3) by comparing their Al-L2,3 EEL spectra. The spectral chemical shift and the fine peak structure of the spectra were consistent with the degree of covalent bonding of Al. This finding will be useful for futu...

  12. Chemical Bonding of AlH3 Hydride by Al-L2,3 Electron Energy-Loss Spectra and First-Principles Calculations

    Directory of Open Access Journals (Sweden)

    Kazutaka Ikeda

    2012-03-01

    Full Text Available In a previous study, we used transmission electron microscopy and electron energy-loss (EEL spectroscopy to investigate dehydrogenation of AlH3 particles. In the present study, we systematically examine differences in the chemical bonding states of Al-containing compounds (including AlH3 by comparing their Al-L2,3 EEL spectra. The spectral chemical shift and the fine peak structure of the spectra were consistent with the degree of covalent bonding of Al. This finding will be useful for future nanoscale analysis of AlH3 dehydrogenation toward the cell.

  13. Significant Reduction in NiO Band Gap upon Formation of LixNi1−xO Alloys: Applications to Solar Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Alidoust, Nima; Toroker, Maytal; Keith, John A.; Carter, Emily A.

    2014-01-01

    Long-term sustainable solar energy conversion relies on identifying economical and versatile semiconductor materials with appropriate band structures for photovoltaic and photocatalytic applications (e.g., band gaps of ∼1.5–2.0 eV). Nickel oxide (NiO) is an inexpensive yet highly promising candidate. Its charge-transfer character may lead to longer carrier lifetimes needed for higher efficiencies, and its conduction band edge is suitable for driving hydrogen evolution via water-splitting. However, NiO’s large band gap (∼4 eV) severely limits its use in practical applications. Our first-principles quantum mechanics calculations show band gaps dramatically decrease to ∼2.0 eV when NiO is alloyed with Li2O. We show that LixNi1−xO alloys (with x=0.125 and 0.25) are p-type semiconductors, contain states with no impurity levels in the gap and maintain NiO’s desirable charge-transfer character. Lastly, we show that the alloys have potential for photoelectrochemical applications, with band edges well-placed for photocatalytic hydrogen production and CO2 reduction, as well as in tandem dye-sensitized solar cells as a photocathode.

  14. 78 FR 16493 - ExxonMobil Canada Energy, Flint Hills Resources Canada, LP, Imperial Oil, NOVA Chemical (Canada...

    Science.gov (United States)

    2013-03-15

    ..., NOVA Chemical (Canada) Ltd., PBF Holding Company LLC, Toledo Refining Company, LLC, Pennzoil-Quaker... Resources Canada, LP, Imperial Oil, NOVA Chemical (Canada) Ltd., PBF Holding Company LLC, Toledo Refining... party must file a notice of intervention or motion to intervene, as appropriate. The Respondent's...

  15. The significance of chemical, isotopic, and detrital components in three coeval stalagmites from the superhumid southernmost Andes (53°S) as high-resolution palaeo-climate proxies

    Science.gov (United States)

    Schimpf, Daniel; Kilian, Rolf; Kronz, Andreas; Simon, Klaus; Spötl, Christoph; Wörner, Gerhard; Deininger, Michael; Mangini, Augusto

    2011-02-01

    Stalagmites are important palaeo-climatic archives since their chemical and isotopic signatures have the potential to record high-resolution changes in temperature and precipitation over thousands of years. We present three U/Th-dated records of stalagmites (MA1-MA3) in the superhumid southern Andes, Chile (53°S). They grew simultaneously during the last five thousand years (ka BP) in a cave that developed in schist and granodiorite. Major and trace elements as well as the C and O isotope compositions of the stalagmites were analysed at high spatial and temporal resolution as proxies for palaeo-temperature and palaeo-precipitation. Calibrations are based on data from five years of monitoring the climate and hydrology inside and outside the cave and on data from 100 years of regional weather station records. Water-insoluble elements such as Y and HREE in the stalagmites indicate the amount of incorporated siliciclastic detritus. Monitoring shows that the quantity of detritus is controlled by the drip water rate once a threshold level has been exceeded. In general, drip rate variations of the stalagmites depend on the amount of rainfall. However, different drip-water pathways above each drip location gave rise to individual drip rate levels. Only one of the three stalagmites (MA1) had sufficiently high drip rates to record detrital proxies over its complete length. Carbonate-compatible element contents (e.g. U, Sr, Mg), which were measured up to sub-annual resolution, document changes in meteoric precipitation and related drip-water dilution. In addition, these soluble elements are controlled by leaching during weathering of the host rock and soils depending on the pH of acidic pore waters in the peaty soils of the cave's catchment area. In general, higher rainfall resulted in a lower concentration of these elements and vice versa. The Mg/Ca record of stalagmite MA1 was calibrated against meteoric precipitation records for the last 100 years from two regional

  16. The Energetic Significance of Cooking

    OpenAIRE

    Wrangham, Richard W.; Carmody, Rachel Naomi

    2009-01-01

    While cooking has long been argued to improve the diet, the nature of the improvement has not been well defined. As a result, the evolutionary significance of cooking has variously been proposed as being substantial or relatively trivial. In this paper, we evaluate the hypothesis that an important and consistent effect of cooking food is a rise in its net energy value. The pathways by which cooking influences net energy value differ for starch, protein and lipid, and we therefore consider pla...

  17. Synthesis of alumina-α using chemical and activation energy por microwave; Sintese de alumina-α utilizando ativacao quimica e energia por microondas

    Energy Technology Data Exchange (ETDEWEB)

    Cartaxo, J.M.; Galdino, M.N.; Neves, G.A., E-mail: juliana@dema.ufcg.edu.br [Universidade Federal de Campina Grande (DEMA/UFCG), PB (Brazil). Unidade Academica de Engenharia de Materiais; Campos, L.F.A.; Menezes, R.R. [Universidade Federal da Paraiba (UFPB), PB (Brazil). Dept. de Engenharia de Materiais; Kiminami, R.H.G.A. [Universidade Federal de Sao Carlos (UFSC), SP (Brazil)

    2012-07-01

    With the great technological advances of alumina, this study aimed to synthesize the α-alumina and chemical activation using microwave energy from aluminum nitrate precursor. The synthesized powders were characterized by X-ray diffraction, thermal analysis (DTA and TGA) and surface area by BET. The chemical activation process was conducted by varying the concentration of the acid solution and exposure time of the material solution. The results proved the effectiveness of chemical activation by accelerating the synthesis process. The results of thermal analysis can observe the thermal decomposition temperature and the possible nucleation of new phases of alumina. The results of X-ray diffraction showed that the powders have the structure of α-alumina with specific areas ranging from 3 to 15m{sup 2}/g pore diameters between 190 to 485nm. (author)

  18. The effect of source chemical composition on the self-attenuation corrections for low-energy gamma-rays in soil samples

    International Nuclear Information System (INIS)

    To study the influence of the source's chemical composition on the self-attenuation corrections during the activity quantification of low-energy gamma-ray emitters (< 60 keV) in soil samples, we conducted a Monte Carlo-based hypothetical proficiency test in which different analytical laboratories analyze a soil sample, assuming the same density but a different chemical composition. The bias in the activity values was between 4% and 70%, with more than 50% of these results being unacceptable. Our work shows that collecting the detailed chemical composition of the samples is an essential issue to be considered by analytical laboratories that use the Monte Carlo method for the calculation of self-attenuation corrections.

  19. Significant Radionuclides Determination

    International Nuclear Information System (INIS)

    The purpose of this calculation is to identify radionuclides that are significant to offsite doses from potential preclosure events for spent nuclear fuel (SNF) and high-level radioactive waste expected to be received at the potential Monitored Geologic Repository (MGR). In this calculation, high-level radioactive waste is included in references to DOE SNF. A previous document, ''DOE SNF DBE Offsite Dose Calculations'' (CRWMS M and O 1999b), calculated the source terms and offsite doses for Department of Energy (DOE) and Naval SNF for use in design basis event analyses. This calculation reproduces only DOE SNF work (i.e., no naval SNF work is included in this calculation) created in ''DOE SNF DBE Offsite Dose Calculations'' and expands the calculation to include DOE SNF expected to produce a high dose consequence (even though the quantity of the SNF is expected to be small) and SNF owned by commercial nuclear power producers. The calculation does not address any specific off-normal/DBE event scenarios for receiving, handling, or packaging of SNF. The results of this calculation are developed for comparative analysis to establish the important radionuclides and do not represent the final source terms to be used for license application. This calculation will be used as input to preclosure safety analyses and is performed in accordance with procedure AP-3.12Q, ''Calculations'', and is subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (DOE 2000) as determined by the activity evaluation contained in ''Technical Work Plan for: Preclosure Safety Analysis, TWP-MGR-SE-000010'' (CRWMS M and O 2000b) in accordance with procedure AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''

  20. Significant Radionuclides Determination

    Energy Technology Data Exchange (ETDEWEB)

    Jo A. Ziegler

    2001-07-31

    The purpose of this calculation is to identify radionuclides that are significant to offsite doses from potential preclosure events for spent nuclear fuel (SNF) and high-level radioactive waste expected to be received at the potential Monitored Geologic Repository (MGR). In this calculation, high-level radioactive waste is included in references to DOE SNF. A previous document, ''DOE SNF DBE Offsite Dose Calculations'' (CRWMS M&O 1999b), calculated the source terms and offsite doses for Department of Energy (DOE) and Naval SNF for use in design basis event analyses. This calculation reproduces only DOE SNF work (i.e., no naval SNF work is included in this calculation) created in ''DOE SNF DBE Offsite Dose Calculations'' and expands the calculation to include DOE SNF expected to produce a high dose consequence (even though the quantity of the SNF is expected to be small) and SNF owned by commercial nuclear power producers. The calculation does not address any specific off-normal/DBE event scenarios for receiving, handling, or packaging of SNF. The results of this calculation are developed for comparative analysis to establish the important radionuclides and do not represent the final source terms to be used for license application. This calculation will be used as input to preclosure safety analyses and is performed in accordance with procedure AP-3.12Q, ''Calculations'', and is subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (DOE 2000) as determined by the activity evaluation contained in ''Technical Work Plan for: Preclosure Safety Analysis, TWP-MGR-SE-000010'' (CRWMS M&O 2000b) in accordance with procedure AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''.

  1. Exploring green catalysts for production of biofuels and value added chemicals for renewable and sustainable energy future

    Science.gov (United States)

    Budhi, Sridhar

    Porous silica have attracted significant attention in the past few decades due to their unique textural properties. They were extensively investigated for applications in catalysis, separation, environmental remediation and drug delivery. We have investigated the porous metal incorporated silica in the synthetic as well as catalytic perspectives. The synthesis of metal incorporated mesoporous silica via co-condensation such as SBA-15, KIT-5 are still challenging as it involves acidic synthetic route. Synthesis in high acidity conditions affects the incorporation of metal in silica due to high dissolution of metal precursors and breaking of metal oxygen and silica bond. The research presented here demonstrates an efficient way to incorporate metals by addition of diammonium hydrogen phosphate along with metal precursor during the synthesis. The incorporation efficiency has increased 2-3 times with this approach. Catalytic studies were performed to support our hypothesis. Such synthesized molybdenum incorporated mesoporous silica were investigated as catalyst for fast pyrolysis. When molydenum incorporated in silica was used as catalyst for fast pyrolysis of pine, it selectively produced furans (furan, methylfuran and dimethylfuran). Furans are considered value-added chemicals and can be used as a blendstock for diesel/jet grade fuel. The catalyst was very stable to harsh pyrolysis conditions and had a longer life before deactivation when compared with traditional zeolites. Further, this catalyst did not produce aromatic hydrocarbons in significant yields unlike zeolites. The origin of the furans was determined to be biopolymer cellulose and the selectivity for furans are attributed to low catalyst acidity. The effect of silica to alumina ratio (SAR) of beta-zeolite was investigated ranging to elucidate the relationship between the of number of acid sites on product speciation and catalyst deactivation on catalysts supplied by Johnson Matthey. The catalyst with low

  2. The study of energy band structure and chemical bonding in yttrium carbide, yttrium and strontium dicarbides by the LMTO and Xα DV method

    International Nuclear Information System (INIS)

    The energy band structures of yttrium carbide, yttrium and strontium dicarbides are studied by the LMTO-method. The cohesive energies and the total and partial pressures are calculated. The local electronic structure of yttrium dicarbide is studied by the Xα discrete variational method; the cluster Y6C2 which includes the group C2-2 and all the nearest neighbours of this group is used in this study. The results of this calculations are used to analyse the chemical bonding and some properties of the compounds. It is shown that the main contribution to the chemical bonding between C2-2 group and yttrium atoms is provided by the orbital of the eg-local symmetry which belongs to the zone of metallic state. In the SrC2 this orbital is empty which explains the instablity of its crystal lattice. (author)

  3. Influence of Chemical Effect on the Kβ/Kα Intensity Ratios and Kβ Energy Shift of Co, Ni, Cu, and Zn Complexes

    Institute of Scientific and Technical Information of China (English)

    G. Apaydma, V. Ayhkg; Z. Biyiklioglu; E. Tirasoglu; H. Kantekin

    2008-01-01

    Chemical effects on the Kβ/Kα intensity ratios and ΔE energy differences for Co, Ni, Cu, and Zn complexes were investigated. The samples were excited by 59.5 keV γ-rays from a 241 Am annular radioactive source. K X-rays emitted by samples were counted by an Ultra-LEGe detector with a resolution of 150 eV at 5.9 keV. We observed the effects of different ligands on the Kβ/Kα intensity ratios and ΔE energy differences for Co, Ni, Cu, and Zn complexes. We tried to investigate chemical effects on central atoms using the behaviors of different ligands in these complexes. The experimental values of Kβ/Kα were compared with the theoretical and other experimental values of pure Co, Ni, Cu, and Zn.

  4. Chemical flashlamps

    International Nuclear Information System (INIS)

    The authors have characterized the optical output and Nd:glass pumping performance of large-scale (120-cm-long, 1.2-cm-inner-diam), metal-oxidizer chemical flashlamps supplied to us by G.T.E. Sylvania. The experimental results were obtained on the same test bed that was used to study xenon electrical flashlamps, as described in Dependence of Flashlamp Performance on Gas Fill and Bore Size, earlier in this section. The peak Nd inversion levels produced by the chemical lamps were less than or equal to 10% of those generated by a xenon lamp of similar size and energy loading. The Peak Nd levels are in good agreement with predictions for the pumping rates in Nd:glass by a blackbody at the color temperatures of 30000 to 50000C, which they have measured during the burn of the pyrotechnic lamp

  5. Best mix of primary energy resources by renewable energy and fossil fuel with CCS in view of security,stability and sustainability——A vision on hydrogen supply chain by organic chemical hydride method

    Institute of Scientific and Technical Information of China (English)

    Junichi; SAKAGUCHI

    2010-01-01

    The best mix scenario by renewable energy and fossil fuel with or without CCS(Carbon Dioxide Capture and Storage) would be a solution to compromise Greenhouse Gases emission issue caused by carbon dioxide(CO2),and depletion of crude oil and natural gas reserves.As fossil fuel with pre-combustion CCS means hydrogen manufacturing and also hydrogen can be produced via electrolysis with renewable energy,it is desirable to establish transportation and storage systems of hydrogen as a clean energy.In this paper a vision on Hydrogen Supply Chain by Organic Chemical Hydride(OCH) Method as well as comparison of CCS configuration are discussed.

  6. Chemical sputtering

    International Nuclear Information System (INIS)

    In this thesis, the author focuses on chemical sputtering by keV ions, treating two specific examples: the chemical effects occurring when bombarding simple condensed gases and the mechanisms of the ion-assisted etching process. First, however, the mechanism of sputtering of condensed gases in general is discussed. These mechanisms have been investigated using condensed noble gases as target material. The thesis is a compilation of articles published elsewhere. Contents: sputtering of condensed noble gases by keV heavy ions; surface distribution as an observable factor in the energy distribution of sputtered particles; reactive sputtering of simple condensed gases by keV heavy ion bombardment; mass spectra of nozzle-produced small molecular clusters of H2O, NH3, CO and CH4; mass and energy distribution of particles sputter-etched from Si in a XeF2 environment; argon-ion assisted etching of silicon by molecular chlorine; energy distribution of sputtered poly-atomic molecules. (Auth.)

  7. Role of atomic hydrogen density and energy in low power chemical vapor deposition synthesis of diamond films

    International Nuclear Information System (INIS)

    Polycrystalline diamond films were synthesized on silicon substrates without diamond seeding by a very low power (∼40-80 W) microwave plasma continuous vapor deposition reaction of a mixture of helium-hydrogen-methane (48.2/48.2/3.6%) or argon-hydrogen-methane (17.5/80/2.5%). However, predominantly graphitic carbon films or no films formed when neon, krypton, or xenon was substituted for helium or argon. The films were characterized by time of flight secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, scanning electron microscopy, and X-ray diffraction. It is proposed that each of He+ and Ar+ served as a catalyst with atomic hydrogen to form an energetic plasma since only plasmas having these ions in the presence of atomic hydrogen showed significantly broadened H α lines corresponding to an average hydrogen atom temperature of >100 eV as reported previously. It was found that not only the energy, but also the H density uniquely increases in He-H2 and Ar-H2 plasmas. Bombardment of the carbon surface by highly energetic hydrogen formed by the catalysis reaction may play a role in the formation of diamond. Then, by this novel pathway, the relevance of the CO tie line is eliminated along with other stringent conditions and complicated and inefficient techniques which limit broad application of the versatility and superiority of diamond thin film technology

  8. Free Energy Minimization Calculation of Complex Chemical Equilibria. Reduction of Silicon Dioxide with Carbon at High Temperature.

    Science.gov (United States)

    Wai, C. M.; Hutchinson, S. G.

    1989-01-01

    Discusses the calculation of free energy in reactions between silicon dioxide and carbon. Describes several computer programs for calculating the free energy minimization and their uses in chemistry classrooms. Lists 16 references. (YP)

  9. Chemical Emergencies

    Science.gov (United States)

    When a hazardous chemical has been released, it may harm people's health. Chemical releases can be unintentional, as in the case of an ... the case of a terrorist attack with a chemical weapon. Some hazardous chemicals have been developed by ...

  10. Wind Energy

    Energy Technology Data Exchange (ETDEWEB)

    Ganley, Jason; Zhang, Jie; Hodge, Bri-Mathias

    2016-03-15

    Wind energy is a variable and uncertain renewable resource that has long been used to produce mechanical work, and has developed into a large producer of global electricity needs. As renewable sources of energy and feedstocks become more important globally to produce sustainable products, many different processes have started adopting wind power as an energy source. Many times this is through a conversion to hydrogen through electrolysis that allows for a more continuous process input. Other important pathways include methanol and ammonia. As the demand for sustainable products and production pathways increases, and wind power capital costs decrease, the role of wind power in chemical and energy production seems poised to increase significantly.

  11. Can nuclear energy support civilized society in the 21st century? From a civilization based on chemical reactions to a civilization based on nuclear reactions

    International Nuclear Information System (INIS)

    The United Nations passed and adopted 'Principles of Sustainable Development' in 1992, as a resolution on the sustainable development of mankind. It advocates maintaining the ecological system to support the earth, while presenting the ethical issue of 'impartiality within a generation', the reduction of absolute poverty and also 'impartiality between generations', in particular 'not leaving a negative legacy to the next generation'. The issue of the appropriate handling of waste is by nature an issue of safety and resources, but is also an ethical issue. Nuclear power generation is more likely to conserve the environment, if the comparison between radioactive waste and carbon dioxide is considered. The creation of hydrogen by nuclear energy resembles the ecological relationship between the sun and the earth in that it consists of the conversion of nuclear energy into chemical energy. Nuclear fission, nuclear fusion, particle acceleration and lasers can all be found in the universe. It will be possible to find a future for nuclear energy by learning from and imitating nature. If the future of nuclear energy is seen from the viewpoint of sustainability, it can be expected that energy resources will be secured and the environment will be conserved by a system of nuclear energy, which will hopefully grow into a comprehensive nuclear science and technology that supports the civilization at its roots. (orig.)

  12. Quantum chemical analysis of the energy of proton transfer from phenol and chlorophenols to H2O in the gas phase and in aqueous solution

    Science.gov (United States)

    Schüürmann, Gerrit

    1998-12-01

    Proton transfer energies of phenol and 14 chlorophenols with H2O as a base are analyzed in the gas phase and in solution using quantum chemical methods at the semiempirical and ab initio level of computation. The effect of aqueous solution was accounted for by applying the density functional theory (DFT) implementation of the conductor-like screening model (COSMO) as well as semiempirical continuum-solvation models. The results reveal substantial and systematic overestimations of the free energies of proton transfer as derived from experimental solution-phase pKa data. This can be traced back to both deficiencies in the current model parameterization as well as to limitations of the underlying gas-phase quantum chemical models, which is further illustrated by additional complete-basis-set (CBS) calculations for the proton transfer reaction with phenol. In contrast, the relative pKa trend is reflected well by COSMO-DFT calculations with correlation coefficients (adjusted for degrees of freedom) of 0.96. Decomposition of the dissociation energy in aqueous solution into a gas-phase term and a term summarizing the solvation contributions provides new insights into the effect of solvation on proton transfer energies, and yields mechanistic explanations for the observed differences in the gas-phase and solution-phase acidity orders of various subgroups of the compounds.

  13. Survey and discussion of models applicable to the transport and fate thrust area of the Department of Energy Chemical and Biological Nonproliferation Program

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-09-01

    The availability and easy production of toxic chemical and biological agents by domestic and international terrorists pose a serious threat to US national security, especially to civilian populations in and around urban areas. To address this threat, the Department of Energy (DOE) has established the Chemical and Biological Nonproliferation Program (CBNP) with the goal of focusing the DOE`s technical resources and expertise on capabilities to deny, deter, mitigate and respond to clandestine releases of chemical and biological agents. With the intent to build on DOE core competencies, the DOE has established six technology thrust areas within the CBNP Program: Biological Information Resources; Point Sensor Systems; Stand-off Detection; Transport and Fate; Decontamination; and Systems Analysis and Integration. The purpose of the Transport and Fate Thrust is to accurately predict the dispersion, concentration and ultimate fate of chemical and biological agents released into the urban and suburban environments and has two major goals: (1) to develop an integrated and validated state-of-the-art atmospheric transport and fate modeling capability for chemical and biological agent releases within the complex urban environment from the regional scale down to building and subway interiors, and (2) to apply this modeling capability in a broad range of simulation case studies of chemical and biological agent release scenarios in suburban, urban and confined (buildings and subways) environments and provide analysis for the incident response user community. Sections of this report discuss subway transport and fate models; buildings interior transport and fate modeling; models for flow and transport around buildings; and local-regional meteorology and dispersion models.

  14. A=D: SIGNIFICANT

    Directory of Open Access Journals (Sweden)

    Samuel Lincoln Bezerra Lins

    2009-07-01

    Full Text Available The lacanian concept of significant is a part of the interpretation in psychoanalytic clinics. To get to this word, Lacan did a re-reading on Freud's texts and articulates it to Saussure's Linguistics. The significant is pre-existent in the subject, and its meaning of speech is directly related to the opposition relationship of a significant to another. The analytical listening aims at establishing a relationship among the significants that the subject does, as well as the own effect that it gives to its speech. Therefore, this article has the goal of th correlating the concept of significant and its expression through films, literature and linguistics, once that the many interactions of psychoanalysis with other sciences makes it more interesting and understandable

  15. Rigorous ab initio quantum embedding for quantum chemistry using Green's function theory: screened interaction, non-local self-energy relaxation, orbital basis, and chemical accuracy

    CERN Document Server

    Lan, Tran Nguyen; Zgid, Dominika

    2016-01-01

    We present a detailed discussion of self-energy embedding theory (SEET) which is a quantum embedding scheme allowing us to describe a chosen subsystem very accurately while keeping the description of the environment at a lower cost. We apply SEET to molecular examples where commonly our chosen subsystem is made out of a set of strongly correlated orbitals while the weakly correlated orbitals constitute an environment. Such a self-energy separation is very general and to make this procedure applicable to multiple systems a detailed and practical procedure for the evaluation of the system and environment self-energy is necessary. We list all the intricacies for one of the possible procedures while focusing our discussion on many practical implementation aspects such as the choice of best orbital basis, impurity solver, and many steps necessary to reach chemical accuracy. Finally, on a set of carefully chosen molecular examples, we demonstrate that SEET which is a controlled, systematically improvable Green's fu...

  16. Reviewing Some Crucial Concepts of Gibbs Energy in Chemical Equilibrium Using a Computer-Assisted, Guided-Problem-Solving Approach

    Science.gov (United States)

    Borge, Javier

    2015-01-01

    G, G°, ?rG, ?rG°, ?G, and ?G° are essential quantities to master the chemical equilibrium. Although the number of publications devoted to explaining these items is extremely high, it seems that they do not produce the desired effect because some articles and textbooks are still being written with some of these quantities that appear to be…

  17. The significance of sex.

    Science.gov (United States)

    Annila, Arto; Annila, Erkki

    2012-12-01

    Sexual and asexual modes of proliferation are associated with advantages and disadvantages, yet a profound percept that would account for both ways of reproduction is missing. On the basis of the 2nd law of thermodynamics we find that both sexual and asexual reproduction can be regarded as a means to consume free energy in least time. Parthenogenesis is a fast way to consume a rich repository of free energy, e.g., an ample stock of food with a large number of individuals, whereas sexual reproduction is a fast way to consume diverse and dispersed resources with a large variety of individuals. Most organisms have adapted to their surroundings accordingly and some organisms switch from one mode of reproduction to the other depending on the amount and dispersion of free-energy sources. We conclude that the least-time free energy consumption in respective surroundings, as the general criterion of natural selection, determines also sexual and asexual modes of reproduction. PMID:23063598

  18. Development of chemical dosimeters

    International Nuclear Information System (INIS)

    A chemical dosimeter is a system that measures the energy by virtue of chemical changes from ionizing absorbed radiation produced unit when it is exposed to ionizing radiation. In all chemical dosimeters radiation induced chemical reaction produces at least one, initially absent species, which is properties long lived enough to determine its quantity or the change in the initial systems. Different types of chemical dosimeters were discussed such as aqueous, gaseous and solid, but the great consideration was given to aqueous systems because of their vital role in setting many processes.(Author)

  19. Characterization of chemical elements in soil submitted to different systems use and management by energy dispersive x-ray fluorescence spectrometry (EDXRF)

    International Nuclear Information System (INIS)

    This study aimed to evaluate the chemical elements levels in soil, submitted to different management systems and use by the Energy Dispersive X-Ray Fluorescence Spectrometry - EDXRF. The systems were T1 - agroforestry (SAF), T2 - native field (CN), T3 - native forest (NM), T4 - tillage forest (PF); T5 - conventional tillage system (SPC) and T6 - system tillage (NT). Samples were collected at 0-10 and 10-20 cm, dried and ground for analysis in EDX-720. The soil showed no difference in the average concentrations of chemical elements analyzed in the profiles, but the systems presented different concentrations of metal elements, and T3 had the highest K, Ca and Zn at 0-10 cm and higher contents of K, Ca, Cu, Zn and Mn in the layer of 10-20 cm. (author)

  20. Vacancy migration energy dependence on local chemical environment in Fe–Cr alloys: A Density Functional Theory study

    International Nuclear Information System (INIS)

    The first step towards the understanding and the modelling of the Fe–Cr alloy kinetic properties consists in estimating the migration energies related to the processes that drive the microstructure evolution. The vacancy’s migration barrier is expected to depend on the vacancy–migrating atom pair atomic environment as pointed out by Nguyen-Manh et al. or Bonny et al. In this paper, we address the issue of the dependence on the vacancy’s local atomic environment of both the vacancy migration energy and the configurational energy change ΔE that occurs when the vacancy jumps towards one of its nearest neighbour sites. A DFT approach is used to determine the ground state energy associated to a given configuration of the system. The results are interpreted in the light of the chromium–chromium and chromium–vacancy binding energies as well as the substitutional chromium atoms magnetic properties

  1. Metal modified graphite. An innovative material for systems converting electro-chemical energy; Metallmodifizierter Graphit. Ein innovativer Werkstoff fuer Systeme zur elektrochemischen Energieumwandlung

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Peter

    2007-07-23

    The work deals with metal modification of graphite electrodes in a water-acid electrolyte solution. The target is to improve the catalytic properties of graphite electrodes as they are applied in redox storage batteries for storing electric energy. Different carbon and graphite materials were used and coated electro-chemically with different metals. After being coated with metal the graphite and carbon electrodes were investigated in terms of changing their catalytic properties by means of impedance measurements. It was shown, a metal coating without a prior activation with electro-chemical oxidation-reduction cycles only results in a low or zero increase of the catalytic properties. Investigations at the electrode material glass carbon showed, a prior activation of the electrode surface by means of electro-chemical oxidation-reduction cycles decreases the penetration resistance. The activation of the glass carbon surface prior to the surface coating with metal is favourable to the electro-chemical properties of the metal-modified electrode. All carbon types, which were used in this work, could be activated at a different level by means of electro-chemical oxidation-reduction cycles depending on the carbon type. The investigations further showed that the edge levels of the carbon were activated by means of the electro-chemical oxidation-reduction cycles. The metal precipitation favourably occurs at the activated positions. (orig.) [German] Die Arbeit befasst sich mit der Metallmodifizierung von Graphitelektroden in waessriger saurer Elektrolytloesung. Ziel ist es die katalytischen Eigenschaften von Graphitelektroden wie sie in Redoxspeicherbatterien zur Speicherung von elektrischer Energie eingesetzt werden zu verbessern. Fuer die Untersuchungen wurden unterschiedliche Kohlenstoff und Graphitmaterialien eingesetzt, die elektrochemisch mit verschiedenen Metallen belegt wurden. Die Graphit- und Kohlenstoffelektroden wurden nach der Metallbelegung durch

  2. Chemical and Petrochemical Sector

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This publication is a background document on the global chemical and petrochemical sector for the IEA publication Energy Technology Transitions in Industry (IEA, 2009). It provides further, more detailed information on the methodology and data issues for energy efficiency indicators for the sector. The indicators discussed offer insight regarding the energy efficiency improvement potential in the short- to medium-term (by proven technologies).

  3. Significant Attributes of Documents.

    Science.gov (United States)

    Armstrong, Frances T.

    The purpose of this paper is to describe a method of finding the significant attributes of documents established during the course of research on the automatic classification of documents. The problem was first approached by examining the way in which an existing hierarchical classification system classifies things. The study of biological…

  4. A Significant Play

    Institute of Scientific and Technical Information of China (English)

    梁海光; 陈明

    2002-01-01

    Yesterday evening, I went to see a play. It was really significant. It was about Zheng Xiaoyue, a very clever and diligent middle school student. Unfortunately, her mother died when she and her brother were very young. Her father was out of work and,

  5. Lack of Statistical Significance

    Science.gov (United States)

    Kehle, Thomas J.; Bray, Melissa A.; Chafouleas, Sandra M.; Kawano, Takuji

    2007-01-01

    Criticism has been leveled against the use of statistical significance testing (SST) in many disciplines. However, the field of school psychology has been largely devoid of critiques of SST. Inspection of the primary journals in school psychology indicated numerous examples of SST with nonrandom samples and/or samples of convenience. In this…

  6. The Significance of Science

    Science.gov (United States)

    Pielke, R.

    2002-05-01

    Whether global warming, terrestrial carbon sinks, ecosystem functioning, genetically modified organisms, cloning, vaccination or chemicals in the environment, science is increasingly the battlefield on which political advocates, not least lawyers and commercial interests, manipulate `facts' to their preferred direction, which fosters the politicization of science. Debate putatively over science increasingly relies on tactics such as ad hominem attacks and criticism of process (for example, peer review or sources of funding), through paid advertisements, press releases and other publicity campaigns. As political battles are waged through `science', many scientists are willing to adopt tactics of demagoguery and character assassination as well as, or even instead of, reasoned argument, as in aspects of debate over genetically modified crops or global warming. Science is becoming yet another playing field for power politics, complete with the trappings of media spin and a win-at-all-costs attitude. Sadly, much of what science can offer policymakers, and hence society, is lost. This talk will use cases from the atmospheric sciences as points of departure to explore the politicization of science from several perspectives and address questions such as: Is it a problem? For whom and what outcomes? What are the alternatives to business-as-usual?

  7. Amorphous silicon carbonitride diaphragm for environmental-cell transmission electron microscope fabricated by low-energy ion beam induced chemical vapor deposition

    Science.gov (United States)

    Matsutani, Takaomi; Yamasaki, Kayo; Imaeda, Norihiro; Kawasaki, Tadahiro

    2015-12-01

    An amorphous silicon carbonitride (a-SiCN) diaphragm for an environmental-cell transmission electron microscope (E-TEM) was fabricated by low-energy ion beam induced chemical vapor deposition (LEIBICVD) with hexamethyldisilazane (HMDSN). The films were prepared by using gaseous HMDSN and N2+ ions with energies ranging from 300 to 600 eV. The diaphragms were applied to Si (1 0 0) and a Cu grid with 100-μm-diameter holes. With increasing ion energy, these diaphragms became perfectly smooth surfaces (RMS = 0.43 nm at 600 eV), as confirmed by atomic force microscopy and TEM. The diaphragms were amorphous and transparent to 200 kV electrons, and no charge-up was observed. Fourier transform infrared spectra and X-ray photoelectron spectra revealed that the elimination of organic compounds and formation of Si-N and C-N bonds can be promoted in diaphragms by increasing the ion impact energy. The resistance to electron beams and reaction gases in the E-cell was improved when the diaphragm was formed with high ion energy.

  8. Chemical Engineering in Space

    Science.gov (United States)

    Lobmeyer, Dennis A.; Meneghelli, Barry; Steinrock, Todd (Technical Monitor)

    2001-01-01

    The aerospace industry has long been perceived as the domain of both physicists and mechanical engineers. This perception has endured even though the primary method of providing the thrust necessary to launch a rocket into space is chemical in nature. The chemical engineering and chemistry personnel behind the systems that provide access to space have labored in the shadows of the physicists and mechanical engineers. As exploration into the cosmos moves farther away from Earth, there is a very distinct need for new chemical processes to help provide the means for advanced space exploration. The state of the art in launch systems uses chemical propulsion systems, primarily liquid hydrogen and liquid oxygen, to provide the energy necessary to achieve orbit. As we move away from Earth, there are additional options for propulsion. Unfortunately, few of these options can compare to the speed or ease of use provided by the chemical propulsion agents. It is with great care and significant cost that gaseous compounds such as hydrogen and oxygen are liquefied and become dense enough to use for rocket fuel. These low-temperature liquids fall within a specialty area known as cryogenics. Cryogenics, the science and art of producing cold operating conditions for use on Earth, in orbit, or on some other nonterrestrial body, has become increasingly important to our ability to travel within our solar system. The production of cryogenic fuels and the long-term storage of these fluids are necessary for travel. As our explorations move farther away from Earth, we need to address how to produce the necessary fuels to make a round-trip. The cost and the size of these expeditions are extreme at best. If we take everything necessary for our survival for the round-trip, we invalidate any chance of travel in the near future. As with the early explorers on Earth, we need to harvest much of our energy and our life support from the celestial bodies. The in situ production of these energy

  9. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    International Nuclear Information System (INIS)

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 × 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies

  10. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    CERN Document Server

    Abreu, P; Ahn, E J; Albuquerque, I F M; Allard, D; Allekotte, I; Allen, J; Allison, P; Castillo, J Alvarez; Alvarez-Muñiz, J; Ambrosio, M; Aminaei, A; Anchordoqui, L; Andringa, S; Antičić, T; Anzalone, A; Aramo, C; Arganda, E; Arqueros, F; Asorey, H; Assis, P; Aublin, J; Ave, M; Avenier, M; Avila, G; Bäcker, T; Balzer, M; Barber, K B; Barbosa, A F; Bardenet, R; Barroso, S L C; Baughman, B; Bäuml, J; Beatty, J J; Becker, B R; Becker, K H; Bellétoile, A; Bellido, J A; BenZvi, S; Berat, C; Bertou, X; Biermann, P L; Billoir, P; Blanco, F; Blanco, M; Bleve, C; Blümer, H; Boháčová, M; Boncioli, D; Bonifazi, C; Bonino, R; Borodai, N; Brack, J; Brogueira, P; Brown, W C; Bruijn, R; Buchholz, P; Bueno, A; Burton, R E; Caballero-Mora, K S; Caramete, L; Caruso, R; Castellina, A; Catalano, O; Cataldi, G; Cazon, L; Cester, R; Chauvin, J; Cheng, S H; Chiavassa, A; Chinellato, J A; Chou, A; Chudoba, J; Clay, R W; Coluccia, M R; Conceição, R; Contreras, F; Cook, H; Cooper, M J; Coppens, J; Cordier, A; Cotti, U; Coutu, S; Covault, C E; Creusot, A; Criss, A; Cronin, J; Curutiu, A; Dagoret-Campagne, S; Dallier, R; Dasso, S; Daumiller, K; Dawson, B R; de Almeida, R M; De Domenico, M; De Donato, C; de Jong, S J; De La Vega, G; Junior, W J M de Mello; Neto, J R T de Mello; De Mitri, I; de Souza, V; de Vries, K D; Decerprit, G; del Peral, L; Deligny, O; Dembinski, H; Dhital, N; Di Giulio, C; Diaz, J C; Castro, M L Díaz; Diep, P N; Dobrigkeit, C; Docters, W; D'Olivo, J C; Dong, P N; Dorofeev, A; Anjos, J C dos; Dova, M T; D'Urso, D; Dutan, I; Ebr, J; Engel, R; Erdmann, M; Escobar, C O; Etchegoyen, A; Luis, P Facal San; Tapia, I Fajardo; Falcke, H; Farrar, G; Fauth, A C; Fazzini, N; Ferguson, A P; Ferrero, A; Fick, B; Filevich, A; Filipčič, A; Fliescher, S; Fracchiolla, C E; Fraenkel, E D; Fröhlich, U; Fuchs, B; Gaior, R; Gamarra, R F; Gambetta, S; García, B; Gámez, D García; Garcia-Pinto, D; Gascon, A; Gemmeke, H; Gesterling, K; Ghia, P L; Giaccari, U; Giller, M; Glass, H; Gold, M S; Golup, G; Albarracin, F Gomez; Berisso, M Gómez; Gonçalves, P; Gonzalez, D; Gonzalez, J G; Gookin, B; Góra, D; Gorgi, A; Gouffon, P; Gozzini, S R; Grashorn, E; Grebe, S; Griffith, N; Grigat, M; Grillo, A F; Guardincerri, Y; Guarino, F; Guedes, G P; Guzman, A; Hague, J D; Hansen, P; Harari, D; Harmsma, S; Harton, J L; Haungs, A; Hebbeker, T; Heck, D; Herve, A E; Hojvat, C; Hollon, N; Holmes, V C; Homola, P; Hörandel, J R; Horneffer, A; Hrabovský, M; Huege, T; Insolia, A; Ionita, F; Italiano, A; Jarne, C; Jiraskova, S; Kadija, K; Kampert, K H; Karhan, P; Kasper, P; Kégl, B; Keilhauer, B; Keivani, A; Kelley, J L; Kemp, E; Kieckhafer, R M; Klages, H O; Kleifges, M; Kleinfeller, J; Knapp, J; Koang, D -H; Kotera, K; Krohm, N; Krömer, O; Kruppke-Hansen, D; Kuehn, F; Kuempel, D; Kulbartz, J K; Kunka, N; La Rosa, G; Lachaud, C; Lautridou, P; Leão, M S A B; Lebrun, D; Lebrun, P; de Oliveira, M A Leigui; Lemiere, A; Letessier-Selvon, A; Lhenry-Yvon, I; López, K Link R; Agüera, A Lopez; Louedec, K; Bahilo, J Lozano; Lucero, A; Ludwig, M; Lyberis, H; Maccarone, M C; Macolino, C; Maldera, S; Mandat, D; Mantsch, P; Mariazzi, A G; Marin, J; Marin, V; Maris, I C; Falcon, H R Marquez; Marsella, G; Martello, D; Martin, L; Martinez, H; Bravo, O Martínez; Mathes, H J; Matthews, J; Matthews, J A J; Matthiae, G; Maurizio, D; Mazur, P O; Medina-Tanco, G; Melissas, M; Melo, D; Menichetti, E; Menshikov, A; Mertsch, P; Meurer, C; Mićanović, S; Micheletti, M I; Miller, W; Miramonti, L; Mollerach, S; Monasor, M; Ragaigne, D Monnier; Montanet, F; Morales, B; Morello, C; Moreno, E; Moreno, J C; Morris, C; Mostafá, M; Moura, C A; Mueller, S; Muller, M A; Müller, G; Münchmeyer, M; Mussa, R; Navarra, G; Navarro, J L; Navas, S; Necesal, P; Nellen, L; Nelles, A; Nhung, P T; Niemietz, L; Nierstenhoefer, N; Nitz, D; Nosek, D; Nožka, L; Nyklicek, M; Oehlschläger, J; Olinto, A; Oliva, P; Olmos-Gilbaja, V M; Ortiz, M; Pacheco, N; Selmi-Dei, D Pakk; Palatka, M; Pallotta, J; Palmieri, N; Parente, G; Parizot, E; Parra, A; Parsons, R D; Pastor, S; Paul, T; Pech, M; Pȩkala, J; Pelayo, R; Pepe, I M; Perrone, L; Pesce, R; Petermann, E; Petrera, S; Petrinca, P; Petrolini, A; Petrov, Y; Petrovic, J; Pfendner, C; Phan, N; Piegaia, R; Pierog, T; Pieroni, P; Pimenta, M; Pirronello, V; Platino, M; Ponce, V H; Pontz, M; Privitera, P; Prouza, M; Quel, E J; Querchfeld, S; Rautenberg, J; Ravel, O; Ravignani, D; Revenu, B; Ridky, J; Riggi, S; Risse, M; Ristori, P; Rivera, H; Rizi, V; Roberts, J; Robledo, C; de Carvalho, W Rodrigues; Rodriguez, G; Martino, J Rodriguez; Rojo, J Rodriguez; Rodriguez-Cabo, I; Rodríguez-Frías, M D; Ros, G; Rosado, J; Rossler, T; Roth, M; Rouillé-d'Orfeuil, B; Roulet, E; Rovero, A C; Rühle, C; Salamida, F; Salazar, H; Salina, G; Sánchez, F; Santander, M; Santo, C E; Santos, E; Santos, E M; Sarazin, F; Sarkar, B; Sarkar, S; Sato, R; Scharf, N; Scherini, V; Schieler, H; Schiffer, P; Schmidt, A; Schmidt, F; Schmidt, T; Scholten, O; Schoorlemmer, H; Schovancova, J; Schovánek, P; Schröder, F; Schulte, S; Schuster, D; Sciutto, S J; Scuderi, M; Segreto, A; Settimo, M; Shadkam, A; Shellard, R C; Sidelnik, I; Sigl, G; Lopez, H H Silva; Śmiałkowski, A; Šmída, R; Snow, G R; Sommers, P; Sorokin, J; Spinka, H; Squartini, R; Stapleton, J; Stasielak, J; Stephan, M; Strazzeri, E; Stutz, A; Suarez, F; Suomijärvi, T; Supanitsky, A D; Šuša, T; Sutherland, M S; Swain, J; Szadkowski, Z; Szuba, M; Tamashiro, A; Tapia, A; Tartare, M; Taşcău, O; Ruiz, C G Tavera; Tcaciuc, R; Tegolo, D; Thao, N T; Thomas, D; Tiffenberg, J; Timmermans, C; Tiwari, D K; Tkaczyk, W; Peixoto, C J Todero; Tomé, B; Tonachini, A; Travnicek, P; Tridapalli, D B; Tristram, G; Trovato, E; Tueros, M; Ulrich, R; Unger, M; Urban, M; Galicia, J F Valdés; Valiño, I; Valore, L; Berg, A M van den; Varela, E; Cárdenas, B Vargas; Vázquez, J R; Vázquez, R A; Veberič, D; Verzi, V; Vicha, J; Videla, M; Villaseñor, L; Wahlberg, H; Wahrlich, P; Wainberg, O; Warner, D; Watson, A A; Weber, M; Weidenhaupt, K; Weindl, A; Westerhoff, S; Whelan, B J; Wieczorek, G; Wiencke, L; Wilczyńska, B; Wilczyński, H; Will, M; Williams, C; Winchen, T; Winders, L; Winnick, M G; Wommer, M; Wundheiler, B; Yamamoto, T; Yapici, T; Younk, P; Yuan, G; Yushkov, A; Zamorano, B; Zas, E; Zavrtanik, D; Zavrtanik, M; Zaw, I; Zepeda, A; Ziolkowski, M

    2011-01-01

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies $E>E_{th}=5.5\\times 10^{19}$ eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at $E>E_{th}$ are heavy nuclei with charge $Z$, the proton component of the sources should lead to excesses in the same regions at energies $E/Z$. We here report the lack of anisotropies in these directions at energies above $E_{th}/Z$ (for illustrative values of $Z=6,\\ 13,\\ 26$). If the anisotropies above $E_{th}$ are due to nuclei with charge $Z$, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

  11. Chemical Potentials of Quarks Extracted from Particle Transverse Momentum Distributions in Heavy Ion Collisions at RHIC Energies

    OpenAIRE

    Hong Zhao; Fu-Hu Liu

    2014-01-01

    In the framework of a multisource thermal model, the transverse momentum distributions of charged particles produced in nucleus-nucleus (A-A) and deuteron-nucleus (d-A) collisions at relativistic heavy ion collider (RHIC) energies are investigated by a two-component revised Boltzmann distribution. The calculated results are in agreement with the PHENIX experimental data. It is found that the source temperature increases obviously with increase of the particle mass and incident energy, but it ...

  12. Trans Hoogsteen/sugar edge base pairing in RNA. Structures, energies, and stabilities from quantum chemical calculations

    Czech Academy of Sciences Publication Activity Database

    Mládek, Arnošt; Sharma, P.; Mitra, A.; Bhattacharyya, D.; Šponer, Jiří; Šponer, Judit E.

    2009-01-01

    Roč. 113, č. 6 (2009), s. 1743-1755. ISSN 1520-6106 R&D Projects: GA AV ČR(CZ) IAA400550701; GA AV ČR(CZ) IAA400040802; GA AV ČR(CZ) 1QS500040581; GA MŠk(CZ) LC06030 Grant ostatní: GA MŠk(CZ) LC512 Institutional research plan: CEZ:AV0Z50040507; CEZ:AV0Z50040702; CEZ:AV0Z40550506 Keywords : quantum chemical calculations * base pairing * RNA Subject RIV: BO - Biophysics Impact factor: 3.471, year: 2009

  13. Significant engineering developments

    International Nuclear Information System (INIS)

    The CANDU nuclear power system is a successful product of creative intelligence combined with the tenacious pursuit of practical solutions to complex engineering challenges. Outstanding engineering developments have transformed a demanding technology into a safe, economic and reliable one. Among the noteworthy developments that have been made CANDU the world's best performing reactor system are those relating to fuel, pressure tubes, heavy water production and management, steam generators, live-load valve packing, pump seals, on-power refuelling and computer control. In addition to pragmatic engineering accomplishments, there has been significant engineering input to guide the direction and shaping of the unique form of safety design and regulation of the CANDU system

  14. Material Characterization in the Electro-Analytic Approach for Applications in Chemical Mechanical Planarization and Electrochemical Energy Systems

    Science.gov (United States)

    Rock, Simon E.

    The work presented in this thesis covers electro-analytical characterization for multiple applications in material science. Electrochemical techniques were used to investigate soluble film formation on metals used in chemical mechanical planarization in order to better understand the removal rate process by studying new chemicals proposed by groups in industry. Second, an ionic liquid was used as an electrolyte in a lithium ion cathode half cell to show the essential functionality of the IL and the temperature advantage over traditional electrolytes. Lastly, a comprehensive measurement for charge recombination in dye-sensitized solar cells was performed using both open-circuit voltage decay and impedance spectroscopy, which may be used to better understand the limiting factors that affect the cell's efficiently. Electrochemical techniques were applied to new methods and materials to extend the development of material manufacturing and advance the measurement process. The fabrication of interconnect structures for semiconductor devices requires low down-pressure chemical mechanical planarization (CMP) of Ta barrier layers. Guanidine carbonate (GC) serves as an effective surface-complexing agent for such CMP applications, where the rate of Ta removal can be chemically controlled through pH-tuned selectivity with respect to the removal of Cu lines. Electrochemical techniques are employed in this work to study the surface-modifying roles of GC that make this chemical an attractive complexing agent for Ta CMP. In addition, the effects of including H2O2 (an oxidizer) and dodecyl benzene sulfonic acid (DBSA, a dissolution inhibitor for Cu) in GC-based CMP solutions are investigated to examine the selective CMP mechanisms of Ta and Cu in these solutions. The results suggest that the removal of Ta is supported in part by structurally weak guanidinium-tantalic-acid surface complexes formed on Ta/Ta2O5. The bicarbonate/carbonate anions of GC also facilitate Ta removal through

  15. Surface free energy ( γsd) of active carbons determined by inverse gas chromatography: influences of the origin of precursors, the burn off level and the chemical modification

    Science.gov (United States)

    Cossarutto, L.; Vagner, C.; Finqueneisel, G.; Weber, J. V.; Zimny, T.

    2001-06-01

    The dispersive component of the surface free energies ( γsd) of commercial active carbons (AC) from various origins were determined by inverse gas chromatography at infinite dilution (IGC-ID). This method discriminates clearly the AC produced from wood (and activated/carbonised with phosphoric acid) and those from coconut-shell (carbonised and steam activated at 850°C). The values for the last AC (from coconut) are twice higher than the values for AC of wood origin. The structure and shape of the pores have to be considered to explain these values. It seems that for AC, IGC-ID globally characterises the most energetic micropores. This can be observed, in this work, by two ways: (i) washing of commercial AC (chemically activated) allows to liberate a part of the micropores blocked by soluble phosphate and consequently increases the γsd value; (ii) modifying coconuts AC by chemical treatment (formamide) results in a strong decrease of both microporosity and γsd value. On the contrary, thermal activation of the modified AC increases at the same time the microporosity and the surface free energy. Finally, we demonstrate that the IGC method is also an useful tool to monitor in situ the evolutions of the surface properties of carbonaceous materials.

  16. The translational, rotational, and vibrational energy effects on the chemical reactivity of water cation H2O+(X 2B1) in the collision with deuterium molecule D2.

    Science.gov (United States)

    Xu, Yuntao; Xiong, Bo; Chang, Yih Chung; Ng, C Y

    2013-07-14

    By employing the newly established vacuum ultraviolet (VUV) laser pulsed field ionization-photoion (PFI-PI) double quadrupole-double octopole ion guide apparatus, we have examined the translational, rotational, and vibrational energy effects on the chemical reactivity of water cation H2O(+)(X(2)B1) in the collision with deuterium molecule D2. The application of a novel electric-field pulsing scheme to the VUV laser PFI-PI ion source has enabled the preparation of a rovibrationally selected H2O(+)(X(2)B1; v1 (+)v2 (+)v3 (+); N(+) K a+Kc+) ion beam with not only high internal-state selectivity and high intensity but also high translational energy resolution. Despite the unfavorable Franck-Condon factors, we are able to prepare the excited vibrational states (v1 (+)v2 (+)v3 (+))=(100) and (020) along with the (000) ground vibrational state, for collisional studies, where v1 (+), v2 (+), and v3 (+) represent the symmetric stretching, bending, and asymmetric stretching modes of H2O(+)(X(2)B1). We show that a range of rotational levels from N(+) K a+Kc+ = 000 to 322, covering a rotational energy range of 0-200 cm(-1) of these vibrational states, can also be generated for absolute integral cross section (σ) measurements at center-of-mass collision energies (Ecms) from thermal energies to 10.00 eV. The Ecm dependences of the σ values are consistent with the prediction of the orbiting model, indicating that translational energy significantly hinders the chemical reactivity of H2O(+)(X(2)B1). Rotational enhancements are observed at Ecm < 0.30 eV for all the three vibrational states, (000), (100), and (020). While the σ values for (100) are found to be only slightly below those for (000), the σ values for (020) are lower than those for (000) and (100) by up to 20% at Ecm ≤ 0.20 eV, indicative of vibrational inhibition at low Ecm by excitation of the (020) mode. Rationalizations are proposed for the observed rotational enhancements and the bending vibrational

  17. A significant hardening and rising shape detected in the MeV/GeV νFν spectrum from the recently discovered very-high-energy blazar S4 0954+65 during the bright optical flare in 2015 February

    Science.gov (United States)

    Tanaka, Yasuyuki T.; Becerra Gonzalez, Josefa; Itoh, Ryosuke; Finke, Justin D.; Inoue, Yoshiyuki; Ojha, Roopesh; Carpenter, Bryce; Lindfors, Elina; Krauß, Felicia; Desiante, Rachele; Shiki, Kensei; Fukazawa, Yasushi; Longo, Francesco; McEnery, Julie E.; Buson, Sara; Nilsson, Kari; Fallah Ramazani, Vandad; Reinthal, Riho; Takalo, Leo; Pursimo, Tapio; Boschin, Walter

    2016-08-01

    We report on Fermi Large Area Telescope (LAT) and multi-wavelength results on the recently discovered very-high-energy (VHE, E > 100 GeV) blazar S4 0954+65 (z = 0.368) during an exceptionally bright optical flare in 2015 February. During the time period (2015 February 13/14, or MJD 57067) when the MAGIC telescope detected VHE γ-ray emission from the source, the Fermi-LAT data indicated a significant spectral hardening at GeV energies, with a power-law photon index of 1.8 ± 0.1-compared with the 3FGL (The Fermi LAT 4-Year Point Source Catalog) value (averaged over four years of observation) of 2.34 ± 0.04. In contrast, Swift X-Ray Telescope data showed a softening of the X-ray spectrum, with a photon index of 1.72 ± 0.08 (compared with 1.38 ± 0.03 averaged during the flare from MJD 57066 to 57077), possibly indicating a modest contribution of synchrotron photons by the highest-energy electrons superposed on the inverse Compton component. Fitting of the quasi-simultaneous ( 100 MeV) and a hard spectral index of ΓGeV up by ground-based Cherenkov telescopes to discover high-redshift blazars, investigate their temporal variability and spectral features in the VHE band, and also constrain the intensity of the extragalactic background light.

  18. Energy efficiency analysis method based on fuzzy DEA cross-model for ethylene production systems in chemical industry

    International Nuclear Information System (INIS)

    DEA (data envelopment analysis) has been widely used for the efficiency analysis of industrial production process. However, the conventional DEA model is difficult to analyze the pros and cons of the multi DMUs (decision-making units). The DEACM (DEA cross-model) can distinguish the pros and cons of the effective DMUs, but it is unable to take the effect of the uncertainty data into account. This paper proposes an efficiency analysis method based on FDEACM (fuzzy DEA cross-model) with Fuzzy Data. The proposed method has better objectivity and resolving power for the decision-making. First we obtain the minimum, the median and the maximum values of the multi-criteria ethylene energy consumption data by the data fuzzification. On the basis of the multi-criteria fuzzy data, the benchmark of the effective production situations and the improvement directions of the ineffective of the ethylene plants under different production data configurations are obtained by the FDEACM. The experimental result shows that the proposed method can improve the ethylene production conditions and guide the efficiency of energy utilization during ethylene production process. - Highlights: • This paper proposes an efficiency analysis method based on FDEACM (fuzzy DEA cross-model) with data fuzzification. • The proposed method is more efficient and accurate than other methods. • We obtain an energy efficiency analysis framework and process based on FDEACM in ethylene production industry. • The proposed method is valid and efficient in improvement of energy efficiency in the ethylene plants

  19. Motion and Energy Chemical Reactions, Parts One and Two of an Integrated Science Sequence, Teacher's Guide, 1973 Edition.

    Science.gov (United States)

    Portland Project Committee, OR.

    This teacher's guide is for the second year of the Portland Project, a three-year integrated secondary science curriculum sequence. The first of two parts in this volume, "Motion and Energy," begins with the study of motion, going from the quantitative description to a consideration of what causes motion and a discussion of Newton's laws. There…

  20. A periodic Energy Decomposition Analysis (pEDA) method for the Investigation of Chemical Bonding in Extended Systems

    CERN Document Server

    Raupach, Marc

    2015-01-01

    The development and first applications of a new periodic energy decomposition analysis (pEDA) scheme for extended systems based on the Kohn-Sham approach to density functional theory are described. The pEDA decomposes the binding energy between two fragments (e.g. the adsorption energy of a molecule on a surface) into several well-defined terms: preparation, electrostatic and dispersion interaction, Pauli repulsion and orbital relaxation energies. The pEDA presented here for an AO-based implementation can handle restricted and unrestricted fragments for 0D to 3D systems considering periodic boundary conditions with and without the determination of fragment occupations. For the latter case, reciprocal space sampling is enabled. The new method gives comparable results to established schemes for molecular systems and shows good convergence with respect to the basis set (TZ2P), the integration accuracy and k-space sampling. Four typical bonding scenarios for surface adsorbate complexes were chosen to highlight th...

  1. Gas revenue increasingly significant

    International Nuclear Information System (INIS)

    This paper briefly describes the wellhead prices of natural gas compared to crude oil over the past 70 years. Although natural gas prices have never reached price parity with crude oil, the relative value of a gas BTU has been increasing. It is one of the reasons that the total amount of money coming from natural gas wells is becoming more significant. From 1920 to 1955 the revenue at the wellhead for natural gas was only about 10% of the money received by producers. Most of the money needed for exploration, development, and production came from crude oil. At present, however, over 40% of the money from the upstream portion of the petroleum industry is from natural gas. As a result, in a few short years natural gas may become 50% of the money revenues generated from wellhead production facilities

  2. Anthropological significance of phenylketonuria.

    Science.gov (United States)

    Saugstad, L F

    1975-01-01

    The highest incidence rates of phenylketonuria (PKU) have been observed in Ireland and Scotlant. Parents heterozygous for PKU in Norway differ significantly from the general population in the Rhesus, Kell and PGM systems. The parents investigated showed an excess of Rh negative, Kell plus and PGM type 1 individuals, which makes them similar to the present populations in Ireland and Scotlant. It is postulated that the heterozygotes for PKU in Norway are descended from a completely assimilated sub-population of Celtic origin, who came or were brought here, 1ooo years ago. Bronze objects of Western European (Scottish, Irish) origin, found in Viking graves widely distributed in Norway, have been taken as evidence of Vikings returning with loot (including a number of Celts) from Western Viking settlements. The continuity of residence since the Viking age in most habitable parts of Norway, and what seems to be a nearly complete regional relationship between the sites where Viking graves contain western imported objects and the birthplaces of grandparents of PKUs identified in Norway, lend further support to the hypothesis that the heterozygotes for PKU in Norway are descended from a completely assimilated subpopulation. The remarkable resemblance between Iceland and Ireland, in respect of several genetic markers (including the Rhesus, PGM and Kell systems), is considered to be an expression of a similar proportion of people of Celtic origin in each of the two countries. Their identical, high incidence rates of PKU are regarded as further evidence of this. The significant decline in the incidence of PKU when one passes from Ireland, Scotland and Iceland, to Denmark and on to Norway and Sweden, is therefore explained as being related to a reduction in the proportion of inhabitants of Celtic extraction in the respective populations. PMID:803884

  3. Meaning and significance of

    Directory of Open Access Journals (Sweden)

    Ph D Student Roman Mihaela

    2011-05-01

    Full Text Available The concept of "public accountability" is a challenge for political science as a new concept in this area in full debate and developement ,both in theory and practice. This paper is a theoretical approach of displaying some definitions, relevant meanings and significance odf the concept in political science. The importance of this concept is that although originally it was used as a tool to improve effectiveness and eficiency of public governance, it has gradually become a purpose it itself. "Accountability" has become an image of good governance first in the United States of America then in the European Union.Nevertheless,the concept is vaguely defined and provides ambiguous images of good governance.This paper begins with the presentation of some general meanings of the concept as they emerge from specialized dictionaries and ancyclopaedies and continues with the meanings developed in political science. The concept of "public accontability" is rooted in economics and management literature,becoming increasingly relevant in today's political science both in theory and discourse as well as in practice in formulating and evaluating public policies. A first conclusin that emerges from, the analysis of the evolution of this term is that it requires a conceptual clarification in political science. A clear definition will then enable an appropriate model of proving the system of public accountability in formulating and assessing public policies, in order to implement a system of assessment and monitoring thereof.

  4. Energy system evaluation of thermo-chemical biofuel production : Process development by integration of power cycles and sustainable electricity

    OpenAIRE

    Bojler Görling, Martin

    2012-01-01

    Fossil fuels dominate the world energy supply today and the transport sector is no exception. Renewable alternatives must therefore be introduced to replace fossil fuels and their emissions, without sacrificing our standard of living. There is a good potential for biofuels but process improvements are essential, to ensure efficient use of a limited amount of biomass and better compete with fossil alternatives. The general aim of this research is therefore to investigate how to improve efficie...

  5. Use of Microporous Nuclear Fuels as a Means of Utilizing the Kinetic Energy of Fission Products in Chemical Synthesis

    International Nuclear Information System (INIS)

    The paper begins by briefly outlining possible uses of the kinetic energy of fission products in the case of gaseous phase weak G reactions. The problem is mainly one of the amount of energy available; industrial production would require ionizing radiation energies of several tens of megawatts. At the second Geneva Conference (September 1958), some of the present authors proposed, for the first time, the use of microporous nuclear fuels as a solution. A body of supplementary data obtained with these fuels in given; they refer to decomposition of N2O, methane radiolysis, and fixation of nitrogen in the form of oxides. The results of the experiments are described with reference to the following parameters: radiation dose, type of radiation, type and dimensions of the microporous support surface. This work confirms the existence of a phenomenon which we term 'heterogeneous radiocatalysis' and enables its nature to be better defined. The nitrogen fixation reaction carried out with these fuels has some interesting features. In some cases, the rate of formation of the nitrogen oxides varies little for oxygen burn-up rates ranging up to 50%. The apparent G, calculated with reference to the total fission energy dissipated in the ''solid/ reactive gas'' system varies, according to case, from 0.1 to 0.4. The temperature is 80o C and the pressure approximately 25 atmospheres. A thorough study of the microstructure of the solids used has been begun, and the spectrum of the pores has been measured. A rough theoretical sketch of the phenomenon of ''heterogenous radiocatalysis'' is tentatively put forward. The paper ends with a discussion of how such microporous fuels could be used in the building of ''chemonuclear '' reactors. A brief study of some possible solutions shows what difficulties are still to be overcome. (author)

  6. Chemical Property in Heavy Ion Collisions

    Science.gov (United States)

    Kaneta, M.

    K-/K+ and bar{p}/p ratios measured in 158 A\\cdotGeV Pb + Pb collisions are shown as a function of centrality and transverse momentum (Pt). Little significant centrality dependence in neither K-/K+ nor bar{p}/p ratios are observed and they are almost constant as a function of Pt. The chemical freeze-out temperature Tch and the chemical potentials for both light and strange quarks (μq, μs) are extracted by comparing the present data with simple model predictions. The μq, μs and Tch from the NA44 are compared with those obtained from similar analysis of SPS S + A and AGS Si + A data. The chemical freeze-out temperature Tch in CERN energy is higher than thermal freeze-out temperature Tfo which is extracted from transverse momentum distribution of charged hadrons. In AGS energy Tch is close to Tfo.

  7. Chemical Composition, In vivo Digestibility and Metabolizable Energy Values of Caramba (Lolium multiflorum cv. caramba) Fresh, Silage and Hay

    OpenAIRE

    Özelçam, H.; Kırkpınar, F.; TAN, K

    2015-01-01

    The experiment was conducted to determine nutritive values of caramba (Lolium multiflorum cv. caramba) fresh, silage and hay by in vivo and in vitro methods. There was a statistically significant difference (p0.05). However, the highest MECN (ME was estimated using crude nutrients) and MEADF values were found in fresh caramba (p

  8. Converting Chemical Energy to Electricity through a Three-Jaw Mini-Generator Driven by the Decomposition of Hydrogen Peroxide.

    Science.gov (United States)

    Xiao, Meng; Wang, Lei; Ji, Fanqin; Shi, Feng

    2016-05-11

    Energy conversion from a mechanical form to electricity is one of the most important research advancements to come from the horizontal locomotion of small objects. Until now, the Marangoni effect has been the only propulsion method to produce the horizontal locomotion to induce an electromotive force, which is limited to a short duration because of the specific property of surfactants. To solve this issue, in this article we utilized the decomposition of hydrogen peroxide to provide the propulsion for a sustainable energy conversion from a mechanical form to electricity. We fabricated a mini-generator consisting of three parts: a superhydrophobic rotator with three jaws, three motors to produce a jet of oxygen bubbles to propel the rotation of the rotator, and three magnets integrated into the upper surface of the rotator to produce the magnet flux. Once the mini-generator was placed on the solution surface, the motor catalyzed the decomposition of hydrogen peroxide. This generated a large amount of oxygen bubbles that caused the generator and integrated magnets to rotate at the air/water interface. Thus, the magnets passed under the coil area and induced a change in the magnet flux, thus generating electromotive forces. We also investigated experimental factors, that is, the concentration of hydrogen peroxide and the turns of the solenoid coil, and found that the mini-generator gave the highest output in a hydrogen peroxide solution with a concentration of 10 wt % and under a coil with 9000 turns. Through combining the stable superhydrophobicity and catalyst, we realized electricity generation for a long duration, which could last for 26 000 s after adding H2O2 only once. We believe this work provides a simple process for the development of horizontal motion and provides a new path for energy reutilization. PMID:27093949

  9. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    OpenAIRE

    Arganda, E.; Arqueros Martínez, Fernando; Blanco Ramos, Francisco; García Pinto, Diego; Ortiz Ramis, Montserrat; Rosado Vélez, Jaime; Vázquez Peñas, José Ramón

    2011-01-01

    The Pierre Auger Collaboration has reported. evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > E-th = 5.5 x 10(19) eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > E-th are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at ener...

  10. Geo-chemical analysis of beach rock samples of Andaman island using energy dispersive X-ray fluorescence (EDXRF) spectrometry

    International Nuclear Information System (INIS)

    Elemental concentrations of beach rock samples have been analyzed using non-destructive technique of energy dispersive X-ray fluorescence (EDXRF) spectrometry. The samples were collected from three different locations of Andaman Island. The concentrations of Al, Ca, K, Fe, Ti, Si, V, Co, Cu, Ba, Zn, Pb, Cd and Mn were determined. The geochemical behavior of elements in the region is discussed. Present study shows that elemental concentrations of beach rock samples from Andaman Islands are much below the values of both earth crust and that of Tamilnadu region. However, the Biogenic element (Ca) showed high concentration compared to all other elements. (author)

  11. A significant hardening and rising shape detected in the MeV/GeV νFν spectrum from the recently discovered very-high-energy blazar S4 0954+65 during the bright optical flare in 2015 February

    Science.gov (United States)

    Tanaka, Yasuyuki T.; Becerra Gonzalez, Josefa; Itoh, Ryosuke; Finke, Justin D.; Inoue, Yoshiyuki; Ojha, Roopesh; Carpenter, Bryce; Lindfors, Elina; Krauß, Felicia; Desiante, Rachele; Shiki, Kensei; Fukazawa, Yasushi; Longo, Francesco; McEnery, Julie E.; Buson, Sara; Nilsson, Kari; Fallah Ramazani, Vandad; Reinthal, Riho; Takalo, Leo; Pursimo, Tapio; Boschin, Walter

    2016-05-01

    We report on Fermi Large Area Telescope (LAT) and multi-wavelength results on the recently discovered very-high-energy (VHE, E > 100 GeV) blazar S4 0954+65 (z = 0.368) during an exceptionally bright optical flare in 2015 February. During the time period (2015 February 13/14, or MJD 57067) when the MAGIC telescope detected VHE γ-ray emission from the source, the Fermi-LAT data indicated a significant spectral hardening at GeV energies, with a power-law photon index of 1.8 ± 0.1-compared with the 3FGL (The Fermi LAT 4-Year Point Source Catalog) value (averaged over four years of observation) of 2.34 ± 0.04. In contrast, Swift X-Ray Telescope data showed a softening of the X-ray spectrum, with a photon index of 1.72 ± 0.08 (compared with 1.38 ± 0.03 averaged during the flare from MJD 57066 to 57077), possibly indicating a modest contribution of synchrotron photons by the highest-energy electrons superposed on the inverse Compton component. Fitting of the quasi-simultaneous ( 100 MeV) and a hard spectral index of ΓGeV < 2.0 detected by Fermi-LAT on daily timescales is a promising target for TeV follow-up by ground-based Cherenkov telescopes to discover high-redshift blazars, investigate their temporal variability and spectral features in the VHE band, and also constrain the intensity of the extragalactic background light.

  12. Chemical characterization of particulate matter suspended in the atmosphere of two Brazilian cities using energy dispersive X-ray fluorescence (EDXRF)

    International Nuclear Information System (INIS)

    The main objective was to evaluate the chemical composition of suspended particulate matter in the atmospheres of Londrina (Parana State) and Piracicaba (Sao Paulo State) - two southern Brazilian cities. The sampling was carried- out in the winter/2002 and summer/2003, with a stacker filter holder, which allowed for the simultaneous collection of fine particles (with aerodynamic diameter smaller than 2.5 μm) and coarse particles (between 2.5 and 10 μm), using 47 mm diameter filters of 0.4 and 8 μm pore diameters, respectively. The sample analyses were carried out with the energy dispersive X-ray fluorescence (EDXRF) technique, using a Mo target X-ray tube and a Si(Li) detector coupled to a multichannel analyzer. The excitation and detection of the characteristic X-rays were done in vacuous (Fe filter, 10 kV, 40 mA) and air atmospheres (Zr filter, 25 kV, 10 mA), quantifying 16 chemical elements in the particulate matter in the range-from Al to Zr. The obtained X-ray spectra were interpreted using the AXIL software and- the chemical element quantification was carried out by the fundamental parameters methodology, employing thin standard films produced by MicroMatter. The accuracy of the analytical method was assessed using a thin glass film, Standard Reference Material produced by the National Bureau of Standards. The average element concentrations in the fine and coarse fractions were different, with S being the major element in the fine fraction in the winter and summer in both cities, and Si, Fe, Al and Ca-in the coarse fraction. The grouping analysis revealed that the elements in the aerosol particles came basically from two sources: soil re-suspension and industrial/anthropogenic activities.

  13. Midrex竖炉化学能与物理能匹配及最大利用的数值分析%Numerical analysis on proportioning and maximum utilization of physical and chemical energies in Midrex shaft furnace

    Institute of Scientific and Technical Information of China (English)

    李强; 刘炳南; 冯明霞; 邹宗树

    2012-01-01

    针对诸如Midrex类型直接还原炼铁竖炉生产过程中存在煤气还原势化学能未能充分利用问题,设计出一种上部增设吹氧装置将过剩化学势转变成热能的竖炉.新型竖炉实现煤气化学能与物理能匹配,从而实现能的最大化利用和减少煤气消耗.根据质量和能量守恒建立了竖炉静态模型对比分析传统和新型竖炉的煤气消耗,同时开发一维动力学模型计算了炉内温度及煤气成分变化,获得了在热力学上盈余煤气的体积分数,即还原煤气过剩化学能的分布.结果表明,吹氧竖炉上部气固两相温度提高,CO和H2浓度明显下降,因而煤气利用率显著增加.在吹氧量为536.40 m3·h-1,吹氧位置为6.5m高度情况下,煤气量消耗下降25.94%,尾气还原势下降53.69%.%Aiming at the incomplete utilization of chemical energy of reducing gas in a shaft furnace like Midrex for direct reduced iron production,oxygen blowing into the upper part of the furnace was proposed to transform the excessive chemical energy into thermal energy. In this way,the proportioning and balancing between chemical and thermal energies of reducing gas in the furnace could be realized,and their maximum utilization and thus gas consumption reduction could be expected. A mass and heat balances model was developed to analyze the gas consumption of both traditional and newly proposed processes. A one-dimensional kinetic model was developed to calculate the composition and temperature profiles of both gas and solid phases in the furnace. The distribution of thermodynamic excess,i. e. the excessive chemical energy of reducing gas was also obtained. The results showed that with oxygen blowing into the upper part of the furnace,the temperatures of both gas and solid phases increased and the concentrations of CO and H2 decreased,and thus gas utilization was increased significantly. In the case of 536. 40 m3 o h-1 oxygen blowing at the furnace height of 6. 5m

  14. Chemical exchange program analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Waffelaert, Pascale

    2007-09-01

    As part of its EMS, Sandia performs an annual environmental aspects/impacts analysis. The purpose of this analysis is to identify the environmental aspects associated with Sandia's activities, products, and services and the potential environmental impacts associated with those aspects. Division and environmental programs established objectives and targets based on the environmental aspects associated with their operations. In 2007 the most significant aspect identified was Hazardous Materials (Use and Storage). The objective for Hazardous Materials (Use and Storage) was to improve chemical handling, storage, and on-site movement of hazardous materials. One of the targets supporting this objective was to develop an effective chemical exchange program, making a business case for it in FY07, and fully implementing a comprehensive chemical exchange program in FY08. A Chemical Exchange Program (CEP) team was formed to implement this target. The team consists of representatives from the Chemical Information System (CIS), Pollution Prevention (P2), the HWMF, Procurement and the Environmental Management System (EMS). The CEP Team performed benchmarking and conducted a life-cycle analysis of the current management of chemicals at SNL/NM and compared it to Chemical Exchange alternatives. Those alternatives are as follows: (1) Revive the 'Virtual' Chemical Exchange Program; (2) Re-implement a 'Physical' Chemical Exchange Program using a Chemical Information System; and (3) Transition to a Chemical Management Services System. The analysis and benchmarking study shows that the present management of chemicals at SNL/NM is significantly disjointed and a life-cycle or 'Cradle-to-Grave' approach to chemical management is needed. This approach must consider the purchasing and maintenance costs as well as the cost of ultimate disposal of the chemicals and materials. A chemical exchange is needed as a mechanism to re-apply chemicals on site. This

  15. Dimensional and chemical characterization of particles at a downwind receptor site of a waste-to-energy plant

    International Nuclear Information System (INIS)

    In the last years numerous epidemiological studies were carried out to evaluate the effects of particulate matter on human health. In industrialized areas, anthropogenic activities highly contribute to the fine and ultrafine particle concentrations. Then, it is important to characterize the evolution of particle size distribution and chemical composition near these emission points. Waste incineration represents a favorable technique for reducing the waste volume. However, in the past, municipal waste incinerators (MWIs) had a bad reputation due to the emission of toxic combustion byproducts. Consequently, the risk perception of the people living near MWIs is very high even if in Western countries waste incineration has nowadays to be considered a relatively clean process from a technical point of view. The study here presented has an exemplary meaning for developing appropriate management and control strategies for air quality in the surrounding of MWIs and to perform exposure assessment for populations involved. Environment particles were continuously measured through a SMPS/APS system over 12 months. The monitoring site represents a downwind receptor of a typical MWI. Furthermore, elements and organic fractions were measured by means of the Instrumental Neutron Activation Analysis and using dichotomous and high volume samplers. Annual mean values of 8.6 x 103 ± 3.7 x 102 part. cm-3 and 31.1 ± 9.0 μg m-3 were found for number and mass concentration, typical of a rural site. Most of the elements can be attributed to long-range transport from other natural and/or anthropogenic sources. Finally, the Polycyclic Aromatic Hydrocarbons present low concentrations with a mean value of 24.6 ng m-3.

  16. Dimensional and chemical characterization of particles at a downwind receptor site of a waste-to-energy plant.

    Science.gov (United States)

    Buonanno, G; Stabile, L; Avino, P; Vanoli, R

    2010-07-01

    In the last years numerous epidemiological studies were carried out to evaluate the effects of particulate matter on human health. In industrialized areas, anthropogenic activities highly contribute to the fine and ultrafine particle concentrations. Then, it is important to characterize the evolution of particle size distribution and chemical composition near these emission points. Waste incineration represents a favorable technique for reducing the waste volume. However, in the past, municipal waste incinerators (MWIs) had a bad reputation due to the emission of toxic combustion byproducts. Consequently, the risk perception of the people living near MWIs is very high even if in Western countries waste incineration has nowadays to be considered a relatively clean process from a technical point of view. The study here presented has an exemplary meaning for developing appropriate management and control strategies for air quality in the surrounding of MWIs and to perform exposure assessment for populations involved. Environment particles were continuously measured through a SMPS/APS system over 12 months. The monitoring site represents a downwind receptor of a typical MWI. Furthermore, elements and organic fractions were measured by means of the Instrumental Neutron Activation Analysis and using dichotomous and high volume samplers. Annual mean values of 8.6 x 10(3)+/-3.7 x 10(2)part.cm(-3) and 31.1+/-9.0 microg m(-3) were found for number and mass concentration, typical of a rural site. Most of the elements can be attributed to long-range transport from other natural and/or anthropogenic sources. Finally, the Polycyclic Aromatic Hydrocarbons present low concentrations with a mean value of 24.6 ng m(-3). PMID:20100651

  17. Catalysis for biomass and CO2 use through solar energy: opening new scenarios for a sustainable and low-carbon chemical production.

    Science.gov (United States)

    Lanzafame, Paola; Centi, Gabriele; Perathoner, Siglinda

    2014-11-21

    The use of biomass, bio-waste and CO2 derived raw materials, the latter synthesized using H2 produced using renewable energy sources, opens new scenarios to develop a sustainable and low carbon chemical production, particularly in regions such as Europe lacking in other resources. This tutorial review discusses first this new scenario with the aim to point out, between the different possible options, those more relevant to enable this new future scenario for the chemical production, commenting in particular the different drivers (economic, technological and strategic, environmental and sustainability and socio-political) which guide the selection. The case of the use of non-fossil fuel based raw materials for the sustainable production of light olefins is discussed in more detail, but the production of other olefins and polyolefins, of drop-in intermediates and other platform molecules are also analysed. The final part discusses the role of catalysis in establishing this new scenario, summarizing the development of catalysts with respect to industrial targets, for (i) the production of light olefins by catalytic dehydration of ethanol and by CO2 conversion via FTO process, (ii) the catalytic synthesis of butadiene from ethanol, butanol and butanediols, and (iii) the catalytic synthesis of HMF and its conversion to 2,5-FDCA, adipic acid, caprolactam and 1,6-hexanediol. PMID:24577063

  18. Studies on acid oils and fatty acids for chickens III. Effect of chemical composition on metabolisable energy of by-products of vegetable oil refining.

    Science.gov (United States)

    Vila, B; Esteve-Garcia, E

    1996-03-01

    1. Fourteen by-products of oil refining, selected for their variability in free fatty acid and unsaponifiable contents, were analysed chemically with the objective of relating the determined ME values of the products to chemical composition by means of multiple linear regression analysis. Refined sunflower oil was included as a reference fat. 2. Twenty-one 2-week-old chicks were used to determine fat digestibilities and AMEn values of diets, using the total collection method. Fats were included in a wheat-soyabean meal diet at 100 g/kg. Multiple linear regression analysis was used to express the ME values of fats as functions of the parameters measured (moisture, gross energy, impurities, unsaponifiables, non eluted material, free fatty acid content, unsaturated: saturated ratio, peroxide value, TBA test). 3. The ME of the fat products lay in the range l2.62 to 24.35 MJ/kg, and 29.26 MJ/kg for refined sunflower oil. Free fatty acid content of the fats was shown to be a poor predictor of their ME values, whereas non eluted material (NEM) of the fat products showed a good correlation with their ME. A regression equation could be derived (R2 0.6548; SEE 2.0064) with the unsaturated: saturated ratio (U:S) and NEM. An ME prediction equation based on the U:S, NEM and unsaponifiable content is also proposed (R2= 0.7l68; SEE= 1.9058). PMID:8833534

  19. Representation of molecules as Fourier series of atomic radial distribution functions: A descriptor for machine learning of potential energy surfaces in chemical compound space

    CERN Document Server

    von Lilienfeld, O Anatole; Knoll, Aaron

    2013-01-01

    A conceptual framework is developed and used to obtain a molecular descriptor for supervised learning of potential energy surfaces. Starting from the external potential, entering any electronic Hamiltonian, the representation is obtained through a Fourier transform, and use of atomic radial distribution functions as arguments for the plane-waves. Its final form consists of a sum over atoms, each term corresponding to a linearly independent analytical function in radial distance around the atom, with units of charge squared. Important properties requirements met include (i) uniqueness and completeness for any compound and geometry, (ii) continuous and differentiable with respect to atomic coordinates and nuclear charges. (iii) invariance with respect to translations, rotations, and atom indexing. In strict analogy to ab initio methods, the only input required are elemental composition and Cartesian coordinates. No pre-conceived knowledge is required about chemical bonding, topology, electronic configurations e...

  20. Three-dimensional chemical mapping with a confocal XRF setup.

    Science.gov (United States)

    Lühl, Lars; Mantouvalou, Ioanna; Schaumann, Ina; Vogt, Carla; Kanngießer, Birgit

    2013-04-01

    A new approach for the nondestructive reconstruction of stratified systems with constant elemental composition but with varying chemical compounds has been developed. The procedure is based on depth scans with a confocal X-ray fluorescence setup at certain energies near absorption edges. These so-called marker energies, where XAFS signals of the involved chemical compounds differ significantly, can also be used to uncover the chemical composition and its topology. A prominent field of application is homogeneous material that is degraded due to chemical reactions like oxidation or reduction. A procedure for the semiquantitative reconstruction of stratified material by means of depth scans at marker energies is elaborated and validated and a three-dimensional mapping is presented. PMID:23445459

  1. Chemical use

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a summary of research and activities related to chemical use on Neal Smith National Wildlife Refuge between 1992 and 2009. The chemicals used on the Refuge...

  2. Chemical bond cleavage induced by electron heating

    International Nuclear Information System (INIS)

    Gas emissions from titanium-metalloid compounds (titanium nitride and oxide) have been investigated to understand the effects of a microwave field on chemical reactions. We employed a high vacuum system (PO2 = 10−6 Pa) to observe in situ reductions. For titanium oxides, H-field heating significantly differed from conventional one in terms of oxygen emissions. For titanium nitride, the emissions were also induced by microwave heating. These tendencies were observed at temperatures above 1000 °C. A quantum chemical interpretation is provided to explain the emissions of the gases, and the experimental data is in good agreement with results predicted using the electronic energy band structure.

  3. Sperm shape abnormalities induced by energy-related hydrocarbons and industrial chemicals. Progress report, January 1-June 30, 1979

    International Nuclear Information System (INIS)

    Using existing and new biological screening and testing systems, the presence of carcinogenic, mutagenic, teratogenic and physiologic or metabolically toxic agents associated with coal and oil shale extraction, conversion or utilization was identified. The purpose of the study is to further develop and apply the detection of morphologically abnormal mammalian sperm as a rapid, simple, quantitative assay of the pathologic response of the male gonad to toxic agents associated with the recovery, process stream, and emission of nonnuclear sources of energy, with primary attention to substances from in situ coal gasification and in situ oil-shale extraction. Changes in mouse sperm head dimensions following low dose x-ray exposure have been compiled and analyzed

  4. Comparison of somatic mutation frequencies at HGPRT locus induced by radiation and chemical pollutant from energy system

    International Nuclear Information System (INIS)

    The somatic induction frequencies of mutation at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus induced by 60Co γ-rays and Benzo-a-pyrene (B(a)P), which are representative of hazardous emission and pollutant from nuclear energy cycle and fossil-fuelled energy cycle respectively, were detected by using forward mutation assay and cloning technique in both V79 Chinese hamster cells and human peripheral blood T-lymphocytes. Resistant mutants were selected with 6-thioguanine (6-TG). Dose-response curves and mathematical expressions were obtained for mutation frequencies and survival following γ-ray and B(a)P(+S9) treatments. The dose ranges for the two mutagens were compared when they induced the same mutation frequencies. In V79/HGPRT assay system, when the mutation frequencies were 5∼35 mutants/106 cells the response of γ-rays in the dose range from 0.93∼4.96 Gy at dose rate of 1.16 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.52∼4.27 μg/ml. By using cloning technique in T-lymphocytes, when the mutation frequencies were 1∼14 mutants/105 cells the response of γ-rays in the dose range from 0.05∼4.77 Gy at dose rate of 1.03 Gy/min is nearly equivalent to that in the B(a)P dose range from 0.15∼7.36 μg/ml. When the survival fraction is 37%, the mutation frequency induced by B(a)P is higher than that induced by 60Co γ-rays

  5. Chemical sensor

    Science.gov (United States)

    Rauh, R. David (Inventor)

    1990-01-01

    A sensor for detecting a chemical substance includes an insertion element having a structure which enables insertion of the chemical substance with a resulting change in the bulk electrical characteristics of the insertion element under conditions sufficient to permit effective insertion; the change in the bulk electrical characteristics of the insertion element is detected as an indication of the presence of the chemical substance.

  6. Chemical machining

    Directory of Open Access Journals (Sweden)

    A. Yardimeden

    2007-08-01

    Full Text Available Purpose: Nontraditional machining processes are widely used to manufacture geometrically complex and precision parts for aerospace, electronics and automotive industries. There are different geometrically designed parts, such as deep internal cavities, miniaturized microelectronics and fine quality components may only be produced by nontraditional machining processes. This paper is aiming to give details of chemical machining process, industrial applications, applied chemical etchants and machined materials. Advantages and disadvantages of the chemical machining are mentioned.Design/methodology/approach: In this study, chemical machining process was described its importance as nontraditional machining process. The steps of process were discussed in detail. The tolerances of machined parts were examined.Findings: Paper describes the chemical machining process, industrial applications, applied chemical etchants and machined materials.Practical implications: The machining operation should be carried out carefully to produce a desired geometry. Environmental laws have important effects when chemical machining is used.Originality/value: The importance of nontraditional machining processes is very high.

  7. Chemical Leukoderma.

    Science.gov (United States)

    Bonamonte, Domenico; Vestita, Michelangelo; Romita, Paolo; Filoni, Angela; Foti, Caterina; Angelini, Gianni

    2016-01-01

    Chemical leukoderma, often clinically mimicking idiopathic vitiligo and other congenital and acquired hypopigmentation, is an acquired form of cutaneous pigment loss caused by exposure to a variety of chemicals that act through selective melanocytotoxicity. Most of these chemicals are phenols and aromatic or aliphatic catechols derivatives. These chemicals, however, are harmful for melanocytes in individuals with an individual susceptibility. Nowadays, chemical leukoderma is fairly common, caused by common domestic products. The presence of numerous acquired confetti- or pea-sized macules is clinically characteristic of chemical leukoderma, albeit not diagnostic. Other relevant diagnostic elements are a history of repeated exposure to a known or suspected depigmenting agent at the sites of onset and a macules distribution corresponding to sites of chemical exposure. Spontaneous repigmentation has been reported when the causative agent is avoided; the repigmentation process is perifollicular and gradual, taking place for a variable period of weeks to months. PMID:27172302

  8. Quantum chemical vibrational study, molecular property, FTIR, FT-Raman spectra, NBO, HOMO-LUMO energies and thermodynamic properties of 1-methyl-2-phenyl benzimidazole

    Science.gov (United States)

    Karnan, M.; Balachandran, V.; Murugan, M.; Murali, M. K.

    2014-09-01

    The solid phase FT-IR and FT-Raman spectra of 1-methyl-2-phenyl benzimidazole (MPBZ) have been recorded in the condensed state. In this work, experimental and theoretical study on the molecular structure, quantum chemical calculations of energies and vibrational wavenumbers of MPBZ is presented. The vibrational frequencies of the title compound were obtained theoretically by DFT/B3LYP calculations employing the standard 6-311+G(d,p) and 6-311++G(d,p) basis set for optimized geometry and were compared with Fourier transform infrared spectrum (FTIR) in the region of 4000-400 cm-1 and with Fourier transform Raman spectrum in the region of 4000-100 cm-1. Complete vibrational assignments, analysis and correlation of the fundamental modes for the title compound were carried out. The vibrational harmonic frequencies were scaled using scale factor, yielding a good agreement between the experimentally recorded and the theoretically calculated values. The study is extended to calculate the HOMO-LUMO energy gap, NBO, mapped molecular electrostatic potential (MEP) surfaces, polarizability, Mulliken charges and thermodynamic properties of the title compound.

  9. CRADA No. NFE-10-02715 Assessment of AFA Stainless Steels for Tube Products in Chemical Processing and Energy Production Applications

    Energy Technology Data Exchange (ETDEWEB)

    Brady, Michael P [ORNL; Yamamoto, Yukinori [ORNL; Epler, Mario [Carpenter Technology Corporation; Magee, John H [Carpenter Technology Corporation

    2011-09-01

    Oak Ridge National Laboratory (ORNL) and Carpenter Technology Corporation (Carpenter) participated in an in-kind cost share cooperative research and development agreement (CRADA) effort under the auspices of the Energy Efficiency and Renewable Energy (EERE) Technology Maturation Program to assess material properties of several potential AFA family grades and explore the feasibility of producing alumina-forming austenitic (AFA) stainless steels in tubular form needed for many power generation and chemical process applications. Carpenter's Research Laboratory successfully vacuum melted 30 lb heats of seven candidate AFA alloy compositions representing a wide range of alloy content and intended application temperatures. These compositions were evaluated by ORNL and Carpenter R&D for microstructure, tensile properties, creep properties, and oxidation resistance. In parallel, additional work was directed toward an initial tube manufacture demonstration of a baseline AFA alloy. Carpenter successfully manufactured a 10,000 lb production heat and delivered appropriate billets to a partner for extrusion evaluation. Tube product was successfully manufactured from the baseline AFA alloy, indicating good potential for commercially produced AFA tubular form material.

  10. Effects of digestible protein to energy ratios on growth and carcass chemical composition of siamese fighting fish (Betta splendens

    Directory of Open Access Journals (Sweden)

    Marcos Vinicius Antunes de Lemos

    2014-02-01

    Full Text Available The expansion in the market of ornamental fish depends on the intensification of production systems and the generation of appropriate technologies. Therefore, it is necessary to know the nutritional requirements of each species for the formulation of nutritionally balanced diets. A 30-day feeding trial was undertaken to evaluate the effects of different dietary digestible protein to energy ratio in diets for Betta splendens fingerlings. Fifty-six all-male B. splendens with 1.03 ± 0.11 g average weight were randomly stocked into 56 1L-aquaria in a completely randomized design with a 2 x 4 factorial arrangement, comprising eight treatments and seven replication. Each fish was considered an experimental unit. Diets were formulated to contain 28.0, 35.0, 42.0 and 49.0% DP and 3,600 and 3,200 kcal/kg DE. The growth parameters evaluated in this trial were weight gain (WG, feed intake (FI, feed conversion ratio (FCR, protein efficiency ratio (PER and specific growth rate (SGR. No difference (P > 0.05 was observed for WG, FCR and SGR. However, a higher FI was observed for fish fed diets containing 42.0% DP (P < 0.05. A positive effect of DP and DE on PER was observed in this study. Generally, according to the increase of DE levels, a reduction on PER was observed. Based on this experimental condition, we recommend the use of 28.0% DP and 3,200 kcal/kg DE in diets for B. splendens.

  11. Non-targeted stressful effects in normal human fibroblast cultures exposed to low fluences of high charge, high energy (HZE) particles: kinetics of biologic responses and significance of secondary radiations

    International Nuclear Information System (INIS)

    The induction of non targeted stressful effects in cell populations exposed to low fluences of high charge (Z) and high energy (E) particles is relevant to estimates of the health risks of space radiation. We investigated the up-regulation of stress markers in confluent normal human fibroblast cultures exposed to 1,000 MeV/u iron ions [linear energy transfer (LET) ∼151 keV/μm] or 600 MeV/u silicon ions (LET ∼50 keV/μm) at mean absorbed doses as low as 0.2 cGy, wherein 1-3% of the cells were targeted through the nucleus by a primary particle. Within 24 h post-irradiation, significant increases in the levels of phospho-TP53 (serine 15), p21Waf1 (CDKN1A), HDM2, phospho-ERK1/2, protein carbonylation and lipid peroxidation were detected, which suggested participation in the stress response of cells not targeted by primary particles. This was supported by in situ studies that indicated greater increases in 53BP1 foci formation, a marker of DNA damage. than expected from the number of primary particle traversals. The effect was expressed as early as 15 min after exposure, peaked at 1 h and decreased by 24 h. A similar tendency occurred after exposure of the cell cultures to 0.2 cGy of 3.7 MeV a particles (LET ∼109 keV/μm) that targets ∼1.6% of nuclei, but not after 0.2 cGy from 290 MeV/u carbon ions (LET ∼13 keV/μm) by which, on average, ∼13% of the nuclei were hit, which highlights the importance of radiation quality in the induced effect. Simulations with the FLUKA multi-particle transport code revealed that fragmentation products, other than electrons, in cell cultures exposed to HZE particles comprise ≤1% of the absorbed dose. Further, the radial spread of dose due to secondary heavy ion fragments is confined to approximately 10-20 μm. Thus, the latter are unlikely to significantly contribute to stressful effects in cells not targeted by primary HZE particles. (authors)

  12. Chemical effects of radiation

    International Nuclear Information System (INIS)

    Ionizing radiations initiate chemical changes in materials because of the high energy of their quanta. In water, highly reactive free radicals are produced which can initiate secondary changes of solutes, and in chemical of biological molecules in contact with the water. Free radicals can also be directly produced in irradiated medical products. Their fate can be identified and the molecular basis of radiation inactivation clarified. Methods have now been developed to protect and minimise such radiation damage. (author)

  13. Interactive Chemical Reactivity Exploration

    OpenAIRE

    Haag, Moritz P.; Vaucher, Alain C.; Bosson, Mael; Redon, Stephane; Reiher, Markus

    2014-01-01

    Elucidating chemical reactivity in complex molecular assemblies of a few hundred atoms is, despite the remarkable progress in quantum chemistry, still a major challenge. Black-box search methods to find intermediates and transition-state structures might fail in such situations because of the high-dimensionality of the potential energy surface. Here, we propose the concept of interactive chemical reactivity exploration to effectively introduce the chemist's intuition into the search process. ...

  14. A combination of 3D-QSAR, docking, local-binding energy (LBE) and GRID study of the species differences in the carcinogenicity of benzene derivatives chemicals.

    Science.gov (United States)

    Fratev, Filip; Benfenati, Emilio

    2008-09-01

    A combination of 3D-QSAR, docking, local-binding energy (LBE) and GRID methods was applied as a tool to study and predict the mechanism of action of 100 carcinogenic benzene derivatives. Two 3D-QSAR models were obtained: (i) model of mouse carcinogenicity on the basis of 100 chemicals (model 1) and (ii) model of the differences in mouse and rat carcinogenicity on the basis of 73 compounds (model 2). 3D-QSAR regression maps indicated the important differences in species carcinogenicity, and the molecular positions associated with them. In order to evaluate the role of P450 metabolic process in carcinogenicity, the following approaches were used. The 3D models of CYP2E1 for mouse and rat were built up. A docking study was applied and the important ligand-protein residues interactions and oxidation positions of the molecules were identified. A new approach for quantitative assessment of metabolism pathways was developed, which enabled us to describe the species differences in CYP2E1 metabolism, and how it can be related to differences in the carcinogenic potential for a subset of compounds. The binding energies of the important substituents (local-binding energy-LBE) were calculated, in order to quantitatively demonstrate the contribution of the substituents in metabolic processes. Furthermore, a computational procedure was used for determining energetically favourable binding sites (GRID examination) of the enzymes. The GRID procedure allowed the identification of some important differences, related to species metabolism in CYP2E1. Comparing GRID, 3D-QSAR maps and LBE results, a similarity was identified, indicating a relationship between P450 metabolic processes and the differences in the carcinogenicity. PMID:18495507

  15. Chemical bonding and electronic structures of the Al2SiO5 polymorphs, andalusite, sillimanite, and kyanite: X-ray photoelectron- and electron energy loss spectroscopy studies

    Energy Technology Data Exchange (ETDEWEB)

    Ohuchi, Fumio S.; Ghose, Subrata; Engelhard, Mark H.; Baer, Donald R.

    2006-05-01

    We have undertaken a detailed analysis of the X-ray photoelectron spectra obtained from the three polymorphs of Al2SiO5; andalusite, sillimanite, and kyanite. Comparison of the spectra was made based on the chemical bonding and structural differences in the Al- and Si-coordination within each polymorph. The spectra for Si(2p) for all three polymorphs are nearly identical, consistent with the fact that all the Si atoms are in 4-fold (tetrahedral) coordination, whereas the binding energies, peak shapes, and peak widths for Al(2p) vary depending on the type of polymorph. The upper-valence band for all three polymorphs is characterized by four main features derived from O(2p), Al(3s), Al(2p), Si(3s), and Si(3p), and the differences in their contributions are observed. The density of state of the Al2SiO5 polymorphs is relatively featureless compared to those observed from ?-SiO2 and ?-Al2O3, suggesting that the orbital overlaps span a greater range in energy. The observed band gap energy for Al2SiO5 (sillimanite) was {approx}9.1eV, a value in between those for ?-SiO2 ({approx}8.6eV) and ?-Al2O3 ({approx}9.6eV). The conduction band feature of Al2SiO5 was experimentally compared to those of ?-SiO2 and ?-Al2O3, and shown that it is indeed intermediate between the ?-SiO2 and ?-Al2O3 phases.

  16. Molecular level control of nanoscale composition and morphology: Toward photocatalytic nanocomposites for solar-to-chemical energy conversion of biomass

    Energy Technology Data Exchange (ETDEWEB)

    Ruberu, Thanthrige P. [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    Understanding the factors influencing nanocrystal formation is a challenge yet to be realized. In comparison to the large number of studies on nanocrystal synthesis and their applications, the number of studies on the effect of the precursor chemistry on nanocrystal composition and shape remains low. Although photochemical fabrication of metalsemiconductor nano-heterostructures is reported in literature, control over the free particle formation and the site of metal deposition have not been achieved. Moreover, utilization of metal- semiconductor nano-heterostructures in photocatalytic reactions other than water splitting is hardly explored. In this thesis, we studied the effect of chalcogenide precursor reactivity on the composition, morphology and the axial anisotropy of cadmiumchalcogenide nanocrystals. We also investigated the influence of the irradiation wavelength in synthesizing metal-semiconductor nano-heterostructures. Finally, we showed that metal semiconductor nano-heterostructures can be used as a photocatalyst for alcohol dehydrogenation reactions. We explored the pathways for the formation of Pt and Pd nanoparticles on CdS and CdS{sub 0.4}Se{sub 0.6} nanorods. This study revealed that the wavelength of irradiation is critical to control free-standing vs. bound metal (Pt and Pd) nanoparticles to semiconductor. Additionally, we observed that metal photodeposition occurs on specific segments of axially anisotropic, compositionally graded CdS0.4Se0.6 nanorods due to the band-gap differential between their nano-domains. We used semiconductor-metal heterostructures for sunlightdriven dehydrogenation and hydrogenolysis of benzyl alcohol. Heterostructure composition dictates activity (turnovers) and product distribution. A few metal (Pt, Pd) islands on the semiconductor surface significantly enhance activity and selectivity and also greatly stabilize the semiconductor against photoinduced etching and degradation.

  17. Potential energy profile, structural, vibrational and reactivity descriptors of trans-2-methoxycinnamic acid by FTIR, FT-Raman and quantum chemical studies

    Science.gov (United States)

    Arjunan, V.; Anitha, R.; Thenmozhi, S.; Marchewka, M. K.; Mohan, S.

    2016-06-01

    The stable conformers of trans-2-methoxycinnamic acid (trans-2MCA) are determined by potential energy profile analysis. The energies of the s-cis and s-trans conformers of trans-2MCA determined by B3LYP/cc-pVTZ method are -612.9788331 Hartrees and -612.9780953 Hartrees, respectively. The vibrational and electronic investigations of the stable s-cis and s-trans conformers of trans-2-methoxycinnamic acid have been carried out extensively with FTIR and FT-Raman spectral techniques. The s-cis conformer (I) with a (C16-C17-C18-O19) dihedral angle equal to 0° is found to be more favoured relative to the one s-trans (II) with (C16-C17-C18-O19) = 180°, possibly due to delocalization, hydrogen bonding and steric repulsion effects between the methoxy and acrylic acid groups. The DFT studies are performed with B3LYP method by utilizing 6-311++G** and cc-pVTZ basis sets to determine the structure, thermodynamic properties, vibrational characteristics and chemical shifts of the compound. The total dipole moments of the conformers determined by B3LYP/cc-pVTZ method are 3.35 D and 4.87 D for s-cis and s-trans, respectively. It reveals the higher polarity of s-trans conformer of trans-2MCA molecule. The electronic and steric influence of the methoxy group on the skeletal frequencies has been analysed. The energies of the frontier molecular orbitals and the LUMO-HOMO energy gap have been determined. The MEP of s-cis conformer lie in the range +1.374e × 10-2 to -1.374e × 10-2 while for s-trans it is +1.591e × 10-2 to -1.591e × 10-2. The total electron density of s-cis conformer lie in the range +5.273e × 10-2 to -5.273e × 10-2 while for s-trans it is +5.403e × 10-2 to -5.403e × 10-2. The MEP and total electron density shows that the s-cis conformer is less polar, less reactive and more stable than the s-trans conformer. All the reactivity descriptors of the molecule have been discussed. Intramolecular electronic interactions and their stabilisation energies have analysed

  18. Acetic acid treatment in S.cerevisiae creates significant energy deficiency and nutrient starvation that is dependent on the activity of mitochondrial transcriptional complex Hap2-3-4-5.

    Directory of Open Access Journals (Sweden)

    AnaKitanovic

    2012-09-01

    Using an automated computer controlled assay system, we investigated and model the dynamic interconnection of biomass yield- and growth rate-dependence on extracellular glucose concentration, pH conditions and acetic acid concentration. Our results show that toxic concentrations of acetic acid inhibit glucose consumption and reduce ethanol production. In absence of carbohydrates uptake, cells initiate synthesis of storage carbohydrates, trehalose and glycogen, and upregulate gluconeogenesis. Accumulation of trehalose and glycogen, and induction of gluconeogenesis depends on mitochondrial activity, investigated by depletion of the Hap2-3-4-5 complex. Analyzing the activity of glycolytic enzymes, glyceraldehyde-3-phosphate dehydrogenase (GAPDH, pyruvate kinase (PYK and glucose-6-phosphate dehydrogenase (G6PDH we found that while high acetic acid concentration increased their activity, lower acetic acids concentrations significantly inhibited these enzymes. With this study we determined growth and functional adjustment of metabolism to acetic acid accumulation in a complex range of extracellular conditions. Our results show that substantial acidification of the intracellular environment, resulting from accumulation of dissociated acetic acid in the cytosol, is required for acetic acid toxicity, which creates a state of energy deficiency and nutrient starvation.

  19. Carbon Nanostructure-Based Field-Effect Transistors for Label-Free Chemical/Biological Sensors

    OpenAIRE

    PingAn Hu; Jia Zhang; Le Li; Zhenlong Wang; William O’Neill; Pedro Estrela

    2010-01-01

    Over the past decade, electrical detection of chemical and biological species using novel nanostructure-based devices has attracted significant attention for chemical, genomics, biomedical diagnostics, and drug discovery applications. The use of nanostructured devices in chemical/biological sensors in place of conventional sensing technologies has advantages of high sensitivity, low decreased energy consumption and potentially highly miniaturized integration. Owing to their particular structu...

  20. Chemical networks*

    OpenAIRE

    Thi Wing-Fai

    2015-01-01

    This chapter discusses the fundamental ideas of how chemical networks are build, their strengths and limitations. The chemical reactions that occur in disks combine the cold phase reactions used to model cold molecular clouds with the hot chemistry applied to planetary atmosphere models. With a general understanding of the different types of reactions that can occur, one can proceed in building a network of chemical reactions and use it to explain the abundance of species seen in disks. One o...