Data acquisition for the HILI [Heavy Ion Light Ion] detector

International Nuclear Information System (INIS)

Teh, K.M.; Shapira, D.; McConnell, J.W.; Kim, H.; Novotny, R.

1987-01-01

A large acceptance, multi-segmented detector system capable of the simultaneous detection of heavy and light ions has been constructed. The heavy ions are detected with a segmented gas ionization chamber and a multiwire proportional counter while the light ions are detected with a 192 element plastic phoswich hodoscope. Processing the large number of signals is accomplished through a combination of CAMAC and FASTBUS modules and preprocessors, and a Host minicomputer. Details of the data acquisition system and the reasons for adopting a dual standards system are discussed. In addition, a technique for processing signals from an individual hodoscope detector is presented. 4 refs., 3 figs

Converting heavy oils into light oils, etc

Energy Technology Data Exchange (ETDEWEB)

Mony, H

1915-12-22

A process is described for transforming heavy oils obtained by the carbonization of lignites, peats, coals, shales into light oils, and also the heavy oils of mineral and vegetable origin, consisting of heating the heavy oils or tars in the presence of one or more solid substances or liquids suitably chosen to cause the distillation of the oils under atmospheric pressure at an appropriate temperature; solid and liquid substances which favor the production of light products under the influence of heat being added preferably to the oil to be treated before putting it in the retort and before heating, so that light oils are obtained by treatment of the heavy oils in a single operation.

Spectra of heavy-light mesons in a relativistic model

Energy Technology Data Exchange (ETDEWEB)

Liu, Jing-Bin; Lue, Cai-Dian [Institute of High Energy Physics, Beijing (China)

2017-05-15

The spectra and wave functions of heavy-light mesons are calculated within a relativistic quark model which is based on a heavy-quark expansion of the instantaneous Bethe-Salpeter equation by applying the Foldy-Wouthuysen transformation. The kernel we choose is the standard combination of linear scalar and Coulombic vector. The effective Hamiltonian for heavy-light quark-antiquark system is calculated up to order 1/m{sub Q}{sup 2}. Our results are in good agreement with available experimental data except for the anomalous D{sub s0}{sup *}(2317) and D{sub s1}(2460) states. The newly observed heavy-light meson states can be accommodated successfully in the relativistic quark model with their assignments presented. The D{sub sJ}{sup *}(2860) can be interpreted as the vertical stroke 1{sup 3/2}D{sub 1} right angle and vertical stroke 1{sup 5/2}D{sub 3} right angle states being members of the 1D family with J{sup P} = 1{sup -} and 3{sup -}. (orig.)

Proceedings of study meeting on microscopic and phenomenological research of interaction for light heavy-ion systems

International Nuclear Information System (INIS)

1991-06-01

The Research Center for Nuclear Physics study meeting 'Microscopic and phenomenological research of interaction for light heavy-ion systems was held on March 7-9, 1990 as the study meeting in the second half of 1990, and 25 researchers took part in it. As the background of holding this study meeting, the fact that recently the rainbow scattering due to nuclear force was discovered experimentally in 16 O- 16 O system, and phenomenologically it was explained only by deep inter-nucleus potential. This should be evaluated as an important foothold for the research on the interaction for light heavy-ion systems and nuclear reaction mechanism. Accordingly, most of the papers presented this time were those related to the inter-nucleus potential and nuclear reaction mechanism. Also the development of theoretical analysis method was carried out and reported. Further, recently the experimental study on the structure and reaction of the neutron rich nucleus has advanced, and the theoretical research related to this topic was reported. (K.I.)

Determination of heavy water in heavy water - light water mixtures

International Nuclear Information System (INIS)

Sanhueza M, A.

1986-01-01

A description about experimental methodology to determine isotopic composition of heavy water - light water mixtures is presented. The employed methods are Nuclear Magnetic Resonance Spectroscopy, for measuring heavy water concentrations from 0 to 100% with intervals of 10% approx., and mass Spectrometry, for measuring heavy water concentrations from 0.1 to 1% with intervals of 0.15% approx., by means of an indirect method of Dilution. (Author)

Drying of heavy water system and works of charging heavy water in Fugen

International Nuclear Information System (INIS)

Matsushita, Tadashi; Iijima, Setsuo

1980-01-01

The advanced thermal reactor ''Fugen'' is the first heavy water-moderated, boiling light water-cooled nuclear reactor for power generation in Japan. It is a large heavy water reactor having about 130 m 3 of heavy water inventory and about 300 m 3 of helium space as the cover gas of the heavy water system. The heavy water required was purchased from FRG, which had been used for the power output test in the KKN, and the quality was 99.82 mol % mean heavy water concentration. The concentration of heavy water for Fugen used for the nuclear design is 99.70 mol%, and it was investigated how heavy water can be charged without lowering the concentration. The matters of investigation include the method of bringing the heavy water and helium system to perfect dryness after washing and light water test, the method of confirming the sufficient dryness to prevent the deterioration, and the method of charging heavy water safely from its containers. On the basis of the results of investigation, the actual works were started. The works of drying the heavy water and helium system by vacuum drying, the works of sampling heavy water and the result of the degree of deterioration, and the works of charging heavy water and the measures to the heavy water remaing in the containers are described. All the works were completed safely and smoothly. (J.P.N.)

Multifragmentation induced by light relativistic projectiles and heavy ions: similarities and differences

International Nuclear Information System (INIS)

Karnaukhov, V.A.; Avdeev, S.P.; Kuznetsov, V.D.

1998-01-01

The experimental data on fragment multiplicities, their energy and charge distributions, the emission times are considered for the nuclear multifragmentation process induced by relativistic light projectiles (protons, helium) and heavy ions. With light projectiles, the multifragmentation is a pure 'thermal' process, well described by the statistical models. Heavy-ion-induced multifragmentation is influenced by dynamic effects related first of all to the compression of the system in the collision. But statistical models can also be applied to rendering the partition of the system if the excitation energy is less than 10 MeV/nucleon and compression is modest. For the central collision of heavy ions the statistical approach fails to describe the data

Lead induced changes in phosphorylation of PSII proteins in low light grown pea plants.

Science.gov (United States)

Wioleta, Wasilewska; Anna, Drożak; Ilona, Bacławska; Kamila, Kąkol; Elżbieta, Romanowska

2015-02-01

Light-intensity and redox-state induced thylakoid proteins phosphorylation involved in structural changes and in regulation of protein turnover. The presence of heavy metal ions triggers a wide range of cellular responses including changes in plant growth and photosynthesis. Plants have evolved a number of mechanisms to protect photosynthetic apparatus. We have characterized the effect of lead on PSII protein phosphorylation in pea (Pisum sativum L.) plants grown in low light conditions. Pb ions affected only slightly photochemical efficiency of PSII and had no effect on organization of thylakoid complexes. Lead activated strongly phosphorylation of PSII core D1 protein and dephosphorylation of this protein did not proceed in far red light. D1 protein was also not degraded in this conditions. However, phosphorylation of LHCII proteins was not affected by lead. These results indicate that Pb(2+) stimulate the phosphorylation of PSII core proteins and by disturbing the disassembly of supercomplexes play a role in PSII repair mechanism. LHCII phosphorylation could control the distribution of energy between the photosystems in low light conditions. This demonstrates that plants may respond to heavy metals by induction different pathways responsible for protein protection under stress conditions.

Heavy-light semileptonic decays in staggered chiral perturbation theory

Science.gov (United States)

Aubin, C.; Bernard, C.

2007-07-01

We calculate the form factors for the semileptonic decays of heavy-light pseudoscalar mesons in partially quenched staggered chiral perturbation theory (SχPT), working to leading order in 1/mQ, where mQ is the heavy-quark mass. We take the light meson in the final state to be a pseudoscalar corresponding to the exact chiral symmetry of staggered quarks. The treatment assumes the validity of the standard prescription for representing the staggered “fourth-root trick” within SχPT by insertions of factors of 1/4 for each sea-quark loop. Our calculation is based on an existing partially quenched continuum chiral perturbation theory calculation with degenerate sea quarks by Bećirević, Prelovsek, and Zupan, which we generalize to the staggered (and nondegenerate) case. As a byproduct, we obtain the continuum partially quenched results with nondegenerate sea quarks. We analyze the effects of nonleading chiral terms, and find a relation among the coefficients governing the analytic valence mass dependence at this order. Our results are useful in analyzing lattice computations of form factors B→π and D→K, when the light quarks are simulated with the staggered action.

Dynamics of light, intermediate, heavy and superheavy nuclear ...

Indian Academy of Sciences (India)

2014-05-01

May 1, 2014 ... Various features related to the dynamics of competing decay modes of nuclear systems are explored by addressing the experimental data of a number of reactions in light, intermediate, heavy and superheavy mass regions. The DCM, being a non-statistical description for the decay of a com- pound nucleus ...

Why heavy and light quarks radiate energy with similar rates

International Nuclear Information System (INIS)

Kopeliovich, B. Z.; Potashnikova, I. K.; Schmidt, Ivan

2010-01-01

The dead-cone effect has been predicted to reduce the magnitude of energy loss and jet quenching for heavy flavors produced with large p T in heavy-ion collisions. On the contrary, data from the Relativistic Heavy Ion Collider demonstrate a strong suppression of high-p T electrons from charm and bottom decays. We show that vacuum radiation of a highly virtual quark produced at high p T with a stripped-off color field develops a much wider dead cone, which screens the one related to the quark mass. Lacking the field, gluons cannot be radiated within this cone until the color field is regenerated and the quark virtuality cools down to the scale of the order of the quark mass. However, this takes longer than is essential for the observed jet quenching, leading to similar nuclear effects for the light and charm quark jets. Open beauty is expected to radiate much less within the p T range studied so far in heavy-ion collisions.

Light-light and heavy-light mesons in the model of QCD string with quarks at the ends

CERN Document Server

Nefediev, A V

2002-01-01

The variational einbein field method is applied to the model of the QCD string with quarks at the ends for the case of light-light and heavy-light mesons. Special attention is payed to the proper string dynamics. The correct string slope of the Regge trajectories is reproduced for light-light states which comes out from the picture of rotating string. Masses of several low-lying orbitally and radially excited states in the D, D_s, B, and B_s meson spectra are calculated and a good agreement with the experimental data as well as with recent lattice calculations is found. The role of the string correction to the interquark interaction is discussed at the example of the identification of D*'(2637) state recently claimed by DELPHI Collaboration. For the heavy-light mesons the standard constants used in Heavy Quark Effective Theory are extracted and compared to the results of other approaches.

Electromagnetic properties of light and heavy baryons in the relativistic quark model

International Nuclear Information System (INIS)

Nicmorus Marinescu, Diana

2007-01-01

One of the main challenges of nowadays low-energy physics remains the description of the internal structure of hadrons, strongly connected to the electromagnetic properties of matter. In this vein, the success of the relativistic quark model in the analysis of the hadron structure constitutes a solid motivation for the study carried out throughout this work. The relativistic quark model is extended to the investigation of static electromagnetic properties of both heavy and light baryons. The bare contributions to the magnetic moments of the single-, double- and triple-heavy baryons are calculated. Moreover, the relativistic quark model allows the study of the electromagnetic properties of the light baryon octet incorporating meson cloud contributions in a perturbative manner. The long disputed values of the multipole ratios E2/M1 and C2/M1 and the electromagnetic form factors of the N→Δγ transition are successfully reproduced. The relativistic quark model can be viewed as a quantum field theory approach based on a phenomenological Lagrangian coupling light and heavy baryons to their constituent quarks. In our approach the baryon is a composite object of three constituent quarks, at least in leading order. The effective interaction Lagrangian is written in terms of baryon and constituent quark fields. The effective action preserves Lorentz covariance and gauge invariance. The main ingredients of the model are already introduced at the level of the interaction Lagrangian: the three-quark baryon currents, the Gaussian distribution of the constituent quarks inside the baryon and the compositeness condition which sets an upper limit for the baryon-quark vertex. The S-matrix elements are expressed by a set of Feynman quark-diagrams. The model contains only few parameters, namely, the cut-off parameter of the Gaussian quark distribution and the free quark propagator, which are unambiguously determined from the best fit to the data. The heavy quark limit within this

Electromagnetic properties of light and heavy baryons in the relativistic quark model

Energy Technology Data Exchange (ETDEWEB)

Nicmorus Marinescu, Diana

2007-06-14

One of the main challenges of nowadays low-energy physics remains the description of the internal structure of hadrons, strongly connected to the electromagnetic properties of matter. In this vein, the success of the relativistic quark model in the analysis of the hadron structure constitutes a solid motivation for the study carried out throughout this work. The relativistic quark model is extended to the investigation of static electromagnetic properties of both heavy and light baryons. The bare contributions to the magnetic moments of the single-, double- and triple-heavy baryons are calculated. Moreover, the relativistic quark model allows the study of the electromagnetic properties of the light baryon octet incorporating meson cloud contributions in a perturbative manner. The long disputed values of the multipole ratios E2/M1 and C2/M1 and the electromagnetic form factors of the N{yields}{delta}{gamma} transition are successfully reproduced. The relativistic quark model can be viewed as a quantum field theory approach based on a phenomenological Lagrangian coupling light and heavy baryons to their constituent quarks. In our approach the baryon is a composite object of three constituent quarks, at least in leading order. The effective interaction Lagrangian is written in terms of baryon and constituent quark fields. The effective action preserves Lorentz covariance and gauge invariance. The main ingredients of the model are already introduced at the level of the interaction Lagrangian: the three-quark baryon currents, the Gaussian distribution of the constituent quarks inside the baryon and the compositeness condition which sets an upper limit for the baryon-quark vertex. The S-matrix elements are expressed by a set of Feynman quark-diagrams. The model contains only few parameters, namely, the cut-off parameter of the Gaussian quark distribution and the free quark propagator, which are unambiguously determined from the best fit to the data. The heavy quark limit

Does behaviour of heavy and light wine buyers differ?

DEFF Research Database (Denmark)

Chrysochou, Polymeros; Lockshin, Larry; Habenschuss, Sarah

and contribution to a brand’s sales, light wine buyers comprise an important target group for small share wine brands. Winemakers of small brands should acknowledge this fact, trying to meet expectations of light buyers as well. In addition, direct marketing strategies could be adapted for each group individually......Purpose: The aim of this paper is to explore the differences in behaviour between heavy and light wine buyers. This is conducted by comparing heavy and light buyers of wine in terms of their repertoires including the size, purchase frequency and market shares across brands, as well as loyalty...... exhibited towards particular wine attributes. Design/methodology/approach: Using panel data of wine purchases in the UK for each buyer group (light and heavy) market shares and loyalty to wine attributes were examined. The polarisation index φ (phi) was used as a measure of loyalty. Findings: The light...

Heavy meson form factors from QCD

International Nuclear Information System (INIS)

Falk, A.F.; Georgi, H.; Grinstein, B.

1990-01-01

We calculate the leading QCD radiative corrections to the relations which follow from the decoupling of the heavy quark spin as the quark mass goes infinity and from the symmetry between systems with different heavy quarks. One of the effects we calculate gives the leading q 2 -dependence of the form factor of a heavy quark, which in turn dominates the q 2 -dependence of the form factors of bound states of the heavy quark with light quarks. This, combined with the normalization of the form factor provided by symmetry, gives us a first principles calculation of the heavy meson (or baryon) form factors in the limit of very large heavy quark mass. (orig.)

A Drinking Water Sensor for Lead and Other Heavy Metals.

Science.gov (United States)

Lin, Wen-Chi; Li, Zhongrui; Burns, Mark A

2017-09-05

Leakage of lead and other heavy metals into drinking water is a significant health risk and one that is not easily detected. We have developed simple sensors containing only platinum electrodes for the detection of heavy metal contamination in drinking water. The two-electrode sensor can identify the existence of a variety of heavy metals in drinking water, and the four-electrode sensor can distinguish lead from other heavy metals in solution. No false-positive response is generated when the sensors are placed in simulated and actual tap water contaminated by heavy metals. Lead detection on the four-electrode sensor is not affected by the presence of common ions in tap water. Experimental results suggest the sensors can be embedded in water service lines for long-time use until lead or other heavy metals are detected. With its low cost (∼$0.10/sensor) and the possibility of long-term operation, the sensors are ideal for heavy metal detection of drinking water.

Radiative decay of light and heavy mesons

International Nuclear Information System (INIS)

Barik, N.; Dash, P.C.

1994-01-01

The M1 transition among the vector (V) and pseudoscalar (P) mesons in the light and heavy flavor sectors has been investigated in a potential model of independent quarks. Going beyond the static approximation, to add some momentum dependence due to the recoil effect in a more realistic calculation, we find an improvement in the results for the radiative decay of light flavored mesons. However, our prediction on the decay rates for the mesons (D * and B * ) in the heavy flavor sector remains unaffected and compares well with those of other model calculations

Faces with Light Makeup Are Better Recognized than Faces with Heavy Makeup.

Science.gov (United States)

Tagai, Keiko; Ohtaka, Hitomi; Nittono, Hiroshi

2016-01-01

Many women wear facial makeup to accentuate their appeal and attractiveness. Makeup may vary from natural (light) to glamorous (heavy), depending of the context of interpersonal situations, an emphasis on femininity, and current societal makeup trends. This study examined how light makeup and heavy makeup influenced attractiveness ratings and facial recognition. In a rating task, 38 Japanese women assigned attractiveness ratings to 36 Japanese female faces with no makeup, light makeup, and heavy makeup (12 each). In a subsequent recognition task, the participants were presented with 36 old and 36 new faces. Results indicated that attractiveness was rated highest for the light makeup faces and lowest for the no makeup faces. In contrast, recognition performance was higher for the no makeup and light make up faces than for the heavy makeup faces. Faces with heavy makeup produced a higher rate of false recognition than did other faces, possibly because heavy makeup creates an impression of the style of makeup itself, rather than the individual wearing the makeup. The present study suggests that light makeup is preferable to heavy makeup in that light makeup does not interfere with individual recognition and gives beholders positive impressions.

Faces with light makeup are better recognized than faces with heavy makeup

Directory of Open Access Journals (Sweden)

Keiko eTagai

2016-03-01

Full Text Available Many women wear facial makeup to accentuate their appeal and attractiveness. Makeup may vary from natural (light to glamorous (heavy, depending of the context of interpersonal situations, an emphasis on femininity, and current societal makeup trends. This study examined how light makeup and heavy makeup influenced attractiveness ratings and facial recognition. In a rating task, 38 Japanese women assigned attractiveness ratings to 36 Japanese female faces with no makeup, light makeup, and heavy makeup (12 each. In a subsequent recognition task, the participants were presented with 36 old and 36 new faces. Results indicated that attractiveness was rated highest for the light makeup faces and lowest for the no makeup faces. In contrast, recognition performance was higher for the no makeup and light make up faces than for the heavy makeup faces. Faces with heavy makeup produced a higher rate of false recognition than did other faces, possibly because heavy makeup creates an impression of the style of makeup itself, rather than the individual wearing the makeup. The present study suggests that light makeup is preferable to heavy makeup in that light makeup does not interfere with individual recognition and gives beholders positive impressions.

Modular Construction of Large Non-Immune Human Antibody Phage-Display Libraries from Variable Heavy and Light Chain Gene Cassettes.

Science.gov (United States)

Lee, Nam-Kyung; Bidlingmaier, Scott; Su, Yang; Liu, Bin

2018-01-01

Monoclonal antibodies and antibody-derived therapeutics have emerged as a rapidly growing class of biological drugs for the treatment of cancer, autoimmunity, infection, and neurological diseases. To support the development of human antibodies, various display techniques based on antibody gene repertoires have been constructed over the last two decades. In particular, scFv-antibody phage display has been extensively utilized to select lead antibodies against a variety of target antigens. To construct a scFv phage display that enables efficient antibody discovery, and optimization, it is desirable to develop a system that allows modular assembly of highly diverse variable heavy chain and light chain (Vκ and Vλ) repertoires. Here, we describe modular construction of large non-immune human antibody phage-display libraries built on variable gene cassettes from heavy chain and light chain repertoires (Vκ- and Vλ-light can be made into independent cassettes). We describe utility of such libraries in antibody discovery and optimization through chain shuffling.

Light-particle emission and heavy residues from nucleus-nucleus collisions

International Nuclear Information System (INIS)

Caplar, R.; Hoelbling, S.; Gentner, R.; Lassen, L.; Oberstedt, A.

1991-01-01

We have investigated the interrelation between light-particle multiplicities and mass resp. charge distributions of heavy residues from complete and incomplete fusion of heavy ions. We have shown that a simple statistical model provides the possibility of quantitatively correlating heavy-residue distributions and corresponding light-particle multiplicities both at the Coulomb barrier and at higher energies where preequilibrium emission occurs. (author). 8 refs, 4 figs, 1 tab

Effect of heavy particles in low-energy light-particle processes

International Nuclear Information System (INIS)

Chan, L.H.; Hagiwara, T.; Ovrut, B.

1979-01-01

The ''decoupling theorem'' of Appelquist and Carazzone is found not always to be applicable to light-scalar-particle processes in spontaneously broken theories. If the Higgs scalar is considered to be light, then Higgs-scalar processes see the effect of heavy fermions and heavy vector gauge bosons at the one-loop level. If there is more than one scalar multiplet in a spontaneously broken gauge theory, the effect of a heavy Higgs particle in light-scalar-particle processes is significant at the tree level. In the latter case, such an effect can be absorbed completely into an effective phi 4 coupling constant, lambda/sub eff/, of the light particle provided that lambda/sub eff/ is positive definite

High-energy elastic recoil detection heavy ions for light element analysis

International Nuclear Information System (INIS)

Goppelt-Langer, P.; Yamamoto, S.; Takeshita, H.; Aoki, Y.; Naramoto, H.

1994-01-01

The detection of light and medium heavy elements in not homogeneous solids is a severe problem in ion beam analysis. Heavy elements can be detected by the well established Rutherford backscattering technique (RBS). In a homogeneous host material most impurities can be easily analyzed by secondary ion mass spectroscopy (SIMS). Some isotopes ( 3 He, 6 Li, 10 B) can be measured by nuclear reaction analysis (NRA) using thermal neutrons inducing (n, p) or (n, α) reactions. Others can be detected by energetic ion beams by nuclear reactions (e.g. 15 N( 1 H, αγ) 12 C for analysis of hydrogen). A high content of H, D or T can be also determined by elastic recoil detection using an energetic He beam. The latter technique has been developed to a universal method for detection of light and heavy elements in any target, using a high energetic heavy ion beam and a detector system, which is able to identify the recoils and delivers energy and position of the particles. (author)

Lattice renormalisation of O(a) improved heavy-light operators

International Nuclear Information System (INIS)

Blossier, B.

2007-05-01

Analytical expressions and numerical values of renormalisation constants of O(a) improved heavy-light currents are given at 1-loop order of perturbation theory in the framework of Heavy Quark Effective Theory: the heavy quark is described by the HYP action and the light quark is described either with the Clover or the Neuberger action. These factors are relevant to extract from a lattice computation the decay constants f B , f B S and the set of bag parameters B i associated with B- anti B mixing phenomenology in the Standard Model and beyond. (orig.)

LEAD ACCUMULATION IN THE ROADSIDE SOILS FROM HEAVY ...

African Journals Online (AJOL)

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ABSTRACT. The levels of lead pollution in the roadside soils of the heavy density motor ways of Eastern ... Heavy metals are not biodegradable and .... Finally, filtration was carried out using Whatman No. 1 filter ... Air-acetylene (99 % purity).

Heavy-light flavor correlations and the QCD phase boundary

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Chihiro [Institute of Theoretical Physics, University of Wroclaw, PL-50204 Wroclaw (Poland); Frankfurt Institute for Advanced Studies, D-60438 Frankfurt am Main (Germany); Redlich, Krzysztof [Institute of Theoretical Physics, University of Wroclaw, PL-50204 Wroclaw (Poland)

2016-12-15

We discuss correlations between the light and heavy-light flavored mesons at finite temperature within a chiral effective theory implementing heavy quark symmetry. We show that the thermodynamics of the charmed mesons is strongly dragged by the chiral crossover dominated by the non-strange flavors. Consequently, the fluctuations carried by the states with strangeness can be used to characterize the onset of the chiral symmetry restoration.

A study of Cirus heavy water system isotopic purity

International Nuclear Information System (INIS)

Thomas, Shibu; Sahu, A.K.; Unni, V.K.P.; Pant, R.C.

2000-01-01

Cirus uses heavy water as moderator and helium as cover gas. Approximately one tonne of heavy water was added to the system every year for routine make up. Isotopic purity (IP) of this water used for addition was always higher than that of the system. Though this should increase IP of heavy water in the system, it has remained almost at the same level, over the years. A study was carried out to estimate the extent of improvement in IP of heavy water in the system that should have occurred because of this and other factors in last 30 years. Reasons for non-occurrence of such an improvement were explored. Ion exchange resins used for purification of heavy water and air ingress into helium cover gas system appear to be the principal sources of entry of light water into heavy water system. (author)

Heavy and Light chain amyloidosois presenting as complete heart block: A rare presentation of a rare disease.

Science.gov (United States)

Priyamvada, P S; Morkhandikar, S; Srinivas, B H; Parameswaran, S

2015-01-01

Amyloidosis is an uncommon disease characterized by deposition of proteinaceous material in the extracellular matrix, which results from abnormal protein folding. Even though more than 25 precursor proteins are identified, majority of systemic amyloidosis results from deposition of abnormal immunoglobulin (Ig) light chains. In heavy chain amyloidosis (AH), deposits are derived from both heavy chain alone, whereas in heavy and light chain amyloidosis (AHL), the deposits are derived from Ig heavy chains and light chains. Both AH and AHL are extremely rare diseases. Here, we report an unusual presentation of IgG (lambda) AHL amyloidosis in the background of multiple myeloma, where the initial clinical presentation was complete heart block, which preceded the definitive diagnosis by 18 months.

Heavy-to-light form factors: Sum rules on the light cone and beyond

International Nuclear Information System (INIS)

Lucha, Wolfgang; Melikhov, Dmitri; Simula, Silvano

2007-01-01

We report the first systematic analysis of the off-light-cone effects in sum rules for heavy-to-light form factors. These effects are investigated in a model based on scalar constituents, which allows a technically rather simple analysis but has the essential features of the analogous QCD calculation. The correlator relevant for the extraction of the heavy-to-light form factor is calculated in two different ways: first, by adopting the full Bethe-Salpeter amplitude of the light meson and, second, by performing the expansion of this amplitude near the light cone x 2 =0. We demonstrate that the contributions to the correlator from the light-cone term x 2 =0 and the off-light-cone terms x 2 ≠0 have the same order in the 1/m Q expansion. The light-cone correlator, corresponding to x 2 =0, is shown to systematically overestimate the full correlator, the difference being ∼Λ QCD /δ, with δ the continuum subtraction parameter of order 1 GeV. Numerically, this difference is found to be 10 divide 20%

Heavy flavour production in proton-lead and lead-lead collisions with LHCb

Science.gov (United States)

Winn, Michael

2017-11-01

The LHCb experiment offers the unique opportunity to study heavy-ion interactions in the forward region (2 kinematic domain complementary to the other 3 large experiments at the LHC. The detector has excellent capabilities for reconstructing quarkonia and open charm states, including baryons, down to zero pT. It can separate the prompt and displaced charm components. In pPb collisions, both forward and backward rapidities are covered thanks to the possibility of beam reversal. Results include measurements of the nuclear modification factor and forward-backward ratio for charmonium, open charm and bottomonium states. These quantities are sensitive probes for nuclear effects in heavy flavour production. Perspectives are given with the large accumulated luminosity during the 2016 pPb run at the LHC. In 2015, LHCb participated successfully for the first time in the PbPb data-taking. The status of the forward prompt J/ψ nuclear modification factor measurement in lead-lead collisions is discussed.

Biochemical and morphological characterization of light and heavy sarcoplasmic reticulum vesicles

Energy Technology Data Exchange (ETDEWEB)

Campbell, K.P.

1978-01-01

Light and heavy sarcoplasmic reticulum vesicles isolated from rabbit leg muscle have been used in a study of chloride-induced calcium release. The biochemical and morphological data indicate that light sarcoplasmic reticulum vesicles are derived from the longitudinal reticulum and heavy sarcoplasmic reticulum vesicles are derived from the terminal cisternae of the sarcoplasmic reticulum. The light and heavy sarcoplasmic reticulum vesicles were both able to accumulate calcium in the presence of ATP to amounts greater than 100 nmoles Ca/sup + +/ per mg of protein in less than one minute. Light and heavy sarcoplasmic reticulum vesicles each had a biphasic time course of calcium uptake. The initial uptake was followed by a rapid release after approximately one minute, of 30 to 40% of the accumulated calcium, which was then followed by a slower phase of calcium accumulation. Results indicate that the chloride induced release of calcium may be acting by two mechanisms, osmotic swelling and depolarization. The release of calcium from the light SR vesicles is probably due to osmotic swelling and the release of calcium from the heavy SR vesicles is probably due to depolarization.

Overview on heavy flavour measurements in lead-lead collisions at the CERN-LHC

CERN Document Server

Mischke, Andre

2013-01-01

High energy collisions of heavy atomic nuclei allow to create and carefully study a high-density, colour-deconfined state of strongly-interacting matter. According to calculations from lattice Quantum-Chromodynamics, under the conditions of high energy density and temperature reached in such collisions, the phase transition to a quark-gluon plasma (QGP) is expected to occur, where the colour confinement of quarks and gluons into hadrons should vanish and chiral symmetry should be restored. Heavy-flavour particles, containing charm and beauty, are unique probes of the conditions of the medium formed in nucleus-nucleus collisions at high energy. In this report recent measurements on open and hidden heavy-flavour production in lead-lead collisions at CERN's Large Hadron Collider are presented and discussed.

Heavy and Light chain amyloidosois presenting as complete heart block: A rare presentation of a rare disease

Directory of Open Access Journals (Sweden)

P S Priyamvada

2015-01-01

Full Text Available Amyloidosis is an uncommon disease characterized by deposition of proteinaceous material in the extracellular matrix, which results from abnormal protein folding. Even though more than 25 precursor proteins are identified, majority of systemic amyloidosis results from deposition of abnormal immunoglobulin (Ig light chains. In heavy chain amyloidosis (AH, deposits are derived from both heavy chain alone, whereas in heavy and light chain amyloidosis (AHL, the deposits are derived from Ig heavy chains and light chains. Both AH and AHL are extremely rare diseases. Here, we report an unusual presentation of IgG (lambda AHL amyloidosis in the background of multiple myeloma, where the initial clinical presentation was complete heart block, which preceded the definitive diagnosis by 18 months.

A nonperturbative treatment of spin-dependent interactions of light and heavy quarkonia

International Nuclear Information System (INIS)

Schoeberl, F.

1986-01-01

We propose a nonrelativistic potential model with a regularized Coulomb potential at short range which leads to spin-dependent interactions which are at most as singular as 1/r. The Schroedinger equation is solved numerically including all spin-dependent interactions nonperturbatively. The predicted spectrum of light and heavy quarkonia is in remarkable agreement with experiment. Even the leptonic decay widths as well as the M1 transitions are in agreement with experiment. (Author)

From global to heavy-light: 5-point conformal blocks

International Nuclear Information System (INIS)

Alkalaev, Konstantin; Belavin, Vladimir

2016-01-01

We consider Virasoro conformal blocks in the large central charge limit. There are different regimes depending on the behavior of the conformal dimensions. The most simple regime is reduced to the global sl(2,ℂ) conformal blocks while the most complicated one is known as the classical conformal blocks. Recently, Fitzpatrick, Kaplan, and Walters showed that the two regimes are related through the intermediate stage of the so-called heavy-light semiclassical limit. We study this idea in the particular case of the 5-point conformal block. To find the 5-point global block we use the projector technique and the Casimir operator approach. Furthermore, we discuss the relation between the global and the heavy-light limits and construct the heavy-light block from the global block. In this way we reproduce our previous results for the 5-point perturbative classical block obtained by means of the monodromy method.

Oil flow in deep waters: comparative study between light oils and heavy oils

Energy Technology Data Exchange (ETDEWEB)

Andreolli, Ivanilto [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

2009-12-19

Ultra deeper waters fields are being exploited due to technological development. Under this scenario, the flow design is accomplished through pipelines subjected to low temperature and high pressure. Moreover, these flow lines are usually long causing a fast fluid cooling, which may affect flow assurance in some cases. Problems during topsides production plant's restart might occur if the oil is viscous and even in steady state a significant different behavior can be noticed, if compared to a less viscous oil. A comparison between light and heavy oil through a case study with the objective to show some heavy oil flow particularities is the purpose of this paper. Permanent and transient analyses for a specific geometry are presented. The results showed that thermal and proper viscosity modeling are required for heavy oil flow, differently from that of light oil flow, due to the exponential viscosity dependence to temperature and because the predominant laminar regime. In addition, on heavier and heavier oil flow systems, it is essential to consider exportation system's restart. (author)

Masses of open-flavour heavy-light hybrids from QCD sum-rules

Energy Technology Data Exchange (ETDEWEB)

Ho, J. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada); Harnett, D. [Department of Physics, University of the Fraser Valley,Abbotsford, BC, V2S 7M8 (Canada); Steele, T.G. [Department of Physics and Engineering Physics, University of Saskatchewan,Saskatoon, SK, S7N 5E2 (Canada)

2017-05-29

We use QCD Laplace sum-rules to predict masses of open-flavour heavy-light hybrids where one of the hybrid’s constituent quarks is a charm or bottom and the other is an up, down, or strange. We compute leading-order, diagonal correlation functions of several hybrid interpolating currents, taking into account QCD condensates up to dimension-six, and extract hybrid mass predictions for all J{sup P}∈{0"±, 1"±}, as well as explore possible mixing effects with conventional quark-antiquark mesons. Within theoretical uncertainties, our results are consistent with a degeneracy between the heavy-nonstrange and heavy-strange hybrids in all J{sup P} channels. We find a similar mass hierarchy of 1{sup +}, 1{sup −}, and 0{sup +} states (a 1{sup +} state lighter than essentially degenerate 1{sup −} and 0{sup +} states) in both the charm and bottom sectors, and discuss an interpretation for the 0{sup −} states. If conventional meson mixing is present the effect is an increase in the hybrid mass prediction, and we estimate an upper bound on this effect.

Moving NRQCD for heavy-to-light form factors on the lattice

International Nuclear Information System (INIS)

Horgan, R.R.; Khomskii, L.; Meinel, S.

2009-06-01

We formulate Non-Relativistic Quantum Chromodynamics (NRQCD) on a lattice which is boosted relative to the usual discretization frame. Moving NRQCD (mNRQCD) allows us to treat the momentum for the heavy quark arising from the frame choice exactly. We derive mNRQCD through O(1/m 2 ,v 4 rel ), as accurate as the NRQCD action in present use, both in the continuum and on the lattice with O(a 4 ) improvements. We have carried out extensive tests of the formalism through calculations of two-point correlators for both heavy-heavy (bottomonium) and heavy-light (B s ) mesons in 2+1 flavor lattice QCD and obtained nonperturbative determinations of energy shift and external momentum renormalization. Comparison to perturbation theory at O(α s ) is also made. The results demonstrate the effectiveness of mNRQCD. In particular we show that the decay constants of heavy-light and heavy-heavy mesons can be calculated with small systematic errors up to much larger momenta than with standard NRQCD. (orig.)

Production of heavy neutrino in next-to-leading order QCD at the LHC and beyond

International Nuclear Information System (INIS)

Das, Arindam; Konar, Partha; Majhi, Swapan

2016-01-01

Majorana and pseudo-Dirac heavy neutrinos are introduced into the type-I and inverse seesaw models, respectively, in explaining the naturally small neutrino mass. TeV scale heavy neutrinos can also be accommodated to have a sizable mixing with the Standard Model light neutrinos, through which they can be produced and detected at the high energy colliders. In this paper we consider the Next-to-Leading Order QCD corrections to the heavy neutrino production, and study the scale variation in cross-sections as well as the kinematic distributions with different final states at 14 TeV LHC and also in the context of 100 TeV hadron collider. The repertoire of the Majorana neutrino is realized through the characteristic signature of the same-sign dilepton pair, whereas, due to a small lepton number violation, the pseudo-Dirac heavy neutrino can manifest the trileptons associated with missing energy in the final state. Using the √s=8 TeV, 20.3 fb"−"1 and 19.7 fb"−"1 data at the ATLAS and CMS respectively, we obtain prospective scale dependent upper bounds of the light-heavy neutrino mixing angles for the Majorana heavy neutrinos at the 14 TeV LHC and 100 TeV collider. Further exploiting a recent study on the anomalous multilepton search by CMS at √s=8 TeV with 19.5 fb"−"1 data, we also obtain the prospective scale dependent upper bounds on the mixing angles for the pseudo-Dirac neutrinos. We thus project a scale dependent prospective reach using the NLO processes at the 14 TeV LHC.

Various light particles emissions accompaning light heavy ion collisions

International Nuclear Information System (INIS)

Billerey, R.

1981-01-01

In this work we have investigated light particles emission accompanying heavy-ion induced reactions. The experiments were performed at the isochronous cyclotron of the I.S.N. de Grenoble and we got in and out of plane correlations between solid state and gazeous detectors. In 14 N (100 MeV) + 27 Al we have chosen, light particles emitted in coincidence with deep inelastic fragments or evaporation residues have been measured. Likewise we observed the correlations between fragments and fragments. The particularities we found between protons and alpha emissions are to be assigned to differences in separation energies, but their relative energies and angular momenta have also a significant part [fr

Simultaneous fit of the spectra of light and heavy self-conjugate mesons

International Nuclear Information System (INIS)

Jena, S.N.

1983-01-01

It is shown that a simultaneous nonrelativistic fit of the spectra of both the light and heavy self-conjugate mesons is possible by an effective non-Coulombic power-law potential of the form V(r) = Ar/sup 0.1/+V 0 . This purely phenomenological potential is found to provide a very good account of the mass spectra and the leptonic decay widths of the rho 0 , theta, psi, and UPSILON systems in a flavor-independent manner. In spite of the smallness of the constituent quark masses involved, the nonrelativistic fit for the light mesons of rho 0 and theta systems is excellent

Evaluation of heavy metals level (arsenic, nickel, mercury and lead effecting on health in drinking water resource of Kohgiluyeh county using geographic information system (GIS

Directory of Open Access Journals (Sweden)

Abdolazim Alinejad

2016-08-01

Full Text Available This study was conducted to determine the amount of heavy metals (Arsenic, Nickel, Mercury, and Lead in drinking water resource of Kohgiluyeh County using Geographic Information System (GIS. This cross-sectional study was conducted on drinking water resource of Kohgiluyeh County (33 water supplies and 4 heavy metals in 2013. 264 samples were analyzed in this study. The experiments were performed at the laboratory of Water and Wastewater Company based on Standard Method. The Atomic Adsorption was used to evaluate the amount of heavy metals. The results were mapping by Geographic Information System software (GIS 9.3 after processing of parameters. Finally, the data were analyzed by SPSS 16 and Excel 2007. The maximum amount of each heavy metal and its resource were shown as follow: Nickel or Ni (Source of w12, 124ppb, Arsenic or As (w33, 42 ppb, Mercury or Hg (w22 and w30, 96ppb, Lead or Pb (w21, 1553ppb. Also, the GIS maps showed that Lead in the central region was very high, Mercury and Arsenic in the northern region were high and Nickel in the eastern and western regions was high. The Kriging method and Gauss model were introduced as best method for interpolation of these metals. Since the concentration of these heavy metals was higher than standard levels in most drinking water supplies in Kohgiluyeh County and these high levels of heavy metals can cause the adverse effects on human health; therefore, the environmental and geological studies are necessary to identify the pollution resource and elimination and removal of heavy metals

Production of heavy flavours at the next-to-leading order

International Nuclear Information System (INIS)

Nason, P.; Ridolfi, G.; Frixione, S.; Mangano, M.L.

1993-01-01

The status of next-to-leading calculations of heavy quark production is reviewed. In particular, results on the doubly-differential cross section for the photoproduction of heavy flavours are discussed. The possibility of using heavy flavour production in order to determine the gluon density in the proton at HERA is also discussed. 3 figs., 22 refs

Moving NRQCD for heavy-to-light form factors on the lattice

Energy Technology Data Exchange (ETDEWEB)

Horgan, R R; Khomskii, L; Meinel, S [Cambridge Univ. (GB). Dept. of Applied Mathematics and Theoretical Physics

2009-06-15

We formulate Non-Relativistic Quantum Chromodynamics (NRQCD) on a lattice which is boosted relative to the usual discretization frame. Moving NRQCD (mNRQCD) allows us to treat the momentum for the heavy quark arising from the frame choice exactly. We derive mNRQCD through O(1/m{sup 2},v{sup 4}{sub rel}), as accurate as the NRQCD action in present use, both in the continuum and on the lattice with O(a{sup 4}) improvements. We have carried out extensive tests of the formalism through calculations of two-point correlators for both heavy-heavy (bottomonium) and heavy-light (B{sub s}) mesons in 2+1 flavor lattice QCD and obtained nonperturbative determinations of energy shift and external momentum renormalization. Comparison to perturbation theory at O({alpha}{sub s}) is also made. The results demonstrate the effectiveness of mNRQCD. In particular we show that the decay constants of heavy-light and heavy-heavy mesons can be calculated with small systematic errors up to much larger momenta than with standard NRQCD. (orig.)

Electrolytic separation factors for oxygen isotopes in light and heavy water solutions

International Nuclear Information System (INIS)

Gulens, J.; Olmstead, W.J.; Longhurst, T.H.; Gale, K.L.; Rolston, J.H.

1987-01-01

The electrolytic separation factor, α, has been measured for /sup 17/O and /sup 18/O at Pt and Ni anodes in both light and heavy water solutions of 6M KOH as a function of current density. For oxygen-17, isotopic separation effects were not observed, within the experimental uncertainty of +-2%, under all conditions studied. For oxygen-18, there is a small difference of 2% in α values between Pt and Ni in both light and heavy water solutions, but there is no significant difference in α values between light and heavy water solutions. In light waters solutions, the separation factor at Pt is small, α(/sup 18/O) ≤ 1.02 for i ≥ 0.1 A/cm/sub 2/. This value agrees reasonably well with theoretical estimates

Faces with Light Makeup Are Better Recognized than Faces with Heavy Makeup

OpenAIRE

Tagai, Keiko; Ohtaka, Hitomi; Nittono, Hiroshi

2016-01-01

Many women wear facial makeup to accentuate their appeal and attractiveness. Makeup may vary from natural (light) to glamorous (heavy), depending of the context of interpersonal situations, an emphasis on femininity, and current societal makeup trends. This study examined how light makeup and heavy makeup influenced attractiveness ratings and facial recognition. In a rating task, 38 Japanese women assigned attractiveness ratings to 36 Japanese female faces with no makeup, light makeup, and he...

Impact of different moderator ratios with light and heavy water cooled reactors in equilibrium states

International Nuclear Information System (INIS)

Permana, Sidik; Takaki, Naoyuki; Sekimoto, Hiroshi

2006-01-01

As an issue of sustainable development in the world, energy sustainability using nuclear energy may be possible using several different ways such as increasing breeding capability of the reactors and optimizing the fuel utilization using spent fuel after reprocessing as well as exploring additional nuclear resources from sea water. In this present study the characteristics of light and heavy water cooled reactors for different moderator ratios in equilibrium states have been investigated. The moderator to fuel ratio (MFR) is varied from 0.1 to 4.0. Four fuel cycle schemes are evaluated in order to investigate the effect of heavy metal (HM) recycling. A calculation method for determining the required uranium enrichment for criticality of the systems has been developed by coupling the equilibrium fuel cycle burn-up calculation and cell calculation of SRAC 2000 code using nuclear data library from the JENDL 3.2. The results show a thermal spectrum peak appears for light water coolant and no thermal peak for heavy water coolant along the MFR (0.1 ≤ MFR ≤ 4.0). The plutonium quality can be reduced effectively by increasing the MFR and number of recycled HM. Considering the effect of increasing number of recycled HM; it is also effective to reduce the uranium utilization and to increase the conversion ratio. trans-Plutonium production such as americium (Am) and curium (Cm) productions are smaller for heavy water coolant than light water coolant. The light water coolant shows the feasibility of breeding when HM is recycled with reducing the MFR. Wider feasible area of breeding has been obtained when light water coolant is replaced by heavy water coolant

Systemic causes of heavy menstrual bleeding

NARCIS (Netherlands)

Verschueren, Sophie

2017-01-01

Heavy menstrual bleeding (HMB) is a common problem in fertile women. In addition to local factors, such as a polyp or a uterine fibroid, systemic causes may lead to HMB. These systemic causes are discussed in this thesis. For years, women with HMB were tested underlying thyroid disorder, but our

Light particle and gamma ray emission measurements in heavy-ion reactions. Progress report

International Nuclear Information System (INIS)

Petitt, G.A.

1982-01-01

The development of a position-sensitive neutron detector and a data acquisition system at HHIRF for studying light particle emission in heavy ion reactions is described. Results are presented and discussed for the reactions 12 C + 158 Gd, 13 C + 157 Gd, and 20 Ne + 150 Nd

Results from proton–lead collisions

CERN Document Server

Mischke, André

2016-01-01

This contribution summarises recent measurements in small collision systems at the Large Hadron Collider (LHC), presented at the 2016 edition of the Annual Large Hadron Collider Physics conference. Three main probes are discussed, namely light flavour (strangeness) production, az- imuthal angular correlations and jets, and open and hidden heavy-flavour production in proton- lead collisions.

Maximizing heavy oil value while minimizing environmental impact with HTL upgrading of heavy to light oil

Energy Technology Data Exchange (ETDEWEB)

Koshka, E. [Ivanhoe Energy Inc., Calgary, AB (Canada)

2009-07-01

This presentation described Ivanhoe Energy Inc.'s proprietary HTL upgrading technology which was designed to process heavy oil in the field to cost effectively produce an upgraded synthetic oil that meets pipeline requirements. Steam and electricity are generated from the energy produced during the process. HTL improves the economics of heavy oil production by reducing the need for natural gas and diluent, and by capturing most of the heavy to light oil price differential. Integrated HTL heavy oil production also provides many environmental benefits regarding greenhouse gas (GHG) emissions. The HTL upgrading process is ready for full scale application. tabs., figs.

Taking account of the recoil effect under a light particle scattering on two heavy particles

International Nuclear Information System (INIS)

Peresypkin, V.V.

1978-01-01

Proceeding from the Faddeev equations the derivation of the Bruekner formula describing a light particle scattering by a system of two fixed force centers is presented. Using the zero-range two-particle potential and assuming the ratio of the incident particle mass to the heavy particle mass to be a small perturbation parameter the correction to the Bruekner formula is obtained taking into account the heavy particle recoil

Process of transforming into light oils heavy oils from carbonization of lignites, coals, etc

Energy Technology Data Exchange (ETDEWEB)

Mony, H

1926-12-20

A process is described for transforming into light oils the heavy oils coming from the carbonization of lignites, peats, coals, and shales, and heavy oils from original minerals and vegetables, consisting of heating the heavy oils or tars in the presence of one or more solid or liquid substances conveniently chosen, with a veiw to effect distillation of the oils under atmospheric pressure at an appropriate temperature, the solids or liquid substances favoring the formation of light products under the influence of heat, being preferably added to the oil before admitting it to the retort and heating, so that the light oils are obtained from the heavy oils in a single operation.

Heavy-quark physics in quantum chromodynamics

International Nuclear Information System (INIS)

Brodsky, S.J.

1991-04-01

Heavy quarks can expose new symmetries and novel phenomena in QCD not apparent in ordinary hadronic systems. In these lectures I discuss the use of effective-Lagrangian and light-cone Fock methods to analyze exclusive heavy hadron decays such as Υ → p bar p and B → ππ, and also to derive effective Schroedinger and Dirac equations for heavy quark systems. Two contributions to the heavy quark structure functions of the proton and other light hadrons are identified: an ''extrinsic'' contribution associated with leading twist QCD evolution of the gluon distribution, and a higher twist ''intrinsic'' contribution due to the hardness of high-mass fluctuations of multi-gluon correlations in hadronic wavefunctions. A non-perturbative calculation of the heavy quark distribution of a meson in QCD in one space and one time is presented. The intrinsic higher twist contributions to the pion and proton structure functions can dominate the hadronic production of heavy quark systems at large longitudinal momentum fraction x F and give anomalous contributions to the quark structure functions of ordinary hadrons at large x bj . I also discuss a number of ways in which heavy quark production in nuclear targets can test fundamental QCD phenomena and provide constraints on hadronic wavefunctions. The topics include color transparency, finite formation time, and predictions for charm production at threshold, including nuclear-bound quarkonium. I also discuss a number of QCD mechanisms for the suppression of J/ψ and Υ production in nuclear collisions, including gluon shadowing, the peripheral excitation of intrinsic heavy quark components at large x F , and the coalescence of heavy quarks with co-moving spectators at low x F

Present status and future perspective of R and D on lead heavy metal-cooled fast reactors

International Nuclear Information System (INIS)

Takahashi, Minoru

2007-01-01

Since a lead heavy metal (lead-bismuth eutectic) is chemically inert and has higher boiling point compared to a sodium, a lead heavy metal-cooled fast reactor can be inherently safe and has good nuclear characteristics and is so suitable to a medium-small size of the reactor. R and D on corrosion of a lead heavy metal has been carried out in the world and this issue might be solved to choose specific corrosion resistant alloys for structural materials and fuel cans of a lead heavy metal-cooled reactor. This article reviews present status and future perspective on lead heavy metal-cooled fast reactors. (T. Tanaka)

Factorization of heavy-to-light form factors in soft-collinear effective theory

CERN Document Server

Beneke, Martin; Feldmann, Th.

2004-01-01

Heavy-to-light transition form factors at large recoil energy of the light meson have been conjectured to obey a factorization formula, where the set of form factors is reduced to a smaller number of universal form factors up to hard-scattering corrections. In this paper we extend our previous investigation of heavy-to-light currents in soft-collinear effective theory to final states with invariant mass Lambda^2 as is appropriate to exclusive B meson decays. The effective theory contains soft modes and two collinear modes with virtualities of order m_b*Lambda (`hard-collinear') and Lambda^2. Integrating out the hard-collinear modes results in the hard spectator-scattering contributions to exclusive B decays. We discuss the representation of heavy-to-light currents in the effective theory after integrating out the hard-collinear scale, and show that the previously conjectured factorization formula is valid to all orders in perturbation theory. The naive factorization of matrix elements in the effective theory ...

Weak decay constants of light and heavy pseudoscalar mesons

Energy Technology Data Exchange (ETDEWEB)

Barik, N [Physics Department, Utkal Univ., Bhubaneswar (India); Kar, S; Dash, P C [Physics Dept., Prananath College, Khurda (India)

1997-05-01

We investigate the weak leptonic decays of light and heavy pseudoscalar mesons in a relativistic quark model of independent quarks. We perform a static calculation of the decay constant f{sub M} purely on grounds of simplicity. In order to minimize the possible uncertainty in the static calculation, we estimate the ratios of the decay constants which are found to be in good agreement, in the heavy flavor sector, with the predictions of other models available in the literature and existing experimental data. However, there is a noticeable discrepancy in the current prediction for pion decay constant which demonstrates the inherent limitations of the static approximation in the study of non-strange light mesons. (author). 25 refs., 1 fig., 3 tabs.

Production of light hydrocarbons, etc. [from heavy hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

1937-10-07

A process is given for the production of light hydrocarbons of the gasoline type and, if desired, of the middle-oil type, from liquid or fusible heavy or medium heavy hydrocarbon materials. The process comprises subjecting the said initial materials in the first stage to catalytic hydrofining, separating the lower boiling constituents and the hydrogenating gas from the resulting products and then subjecting the higher boiling constituents in a second stage to a splitting destructive hydrogenation and then recycling substantially the entire reaction mixture obtained in the second stage to the frst stage.

Dominance of the light-quark condensate in the heavy-to-light exclusive decays

CERN Document Server

Narison, Stéphan

1995-01-01

Using the QCD {\\it hybrid} (moments--Laplace) sum rule, we show semi--analytically that, in the limit M_b \\rar \\infty, the q^2 and M_b behaviours of the heavy--to--light exclusive (\\bar B\\rar \\rho~(\\pi) semileptonic as well as the B\\rar \\rho\\gamma rare) decay--form factors are universally dominated by the contribution of the soft light--quark condensate rather than that of the hard perturbative diagram. The QCD--analytic q^2 behaviour of the form factors is a polynomial in q^2/M^2_b, which mimics quite well the usual pole parametrization, except in the case of the A_1^B form factor, where there is a significant deviation from this polar form. The M_b--dependence of the form factors expected from HQET and lattice results is recovered. We extract with a good accuracy the ratios: V^B(0)/A^B_1(0) \\simeq A^B_2(0)/A^B_1(0) \\simeq 1.18\\pm 0.04, A^B_1(0)/f^B_+(0) \\simeq 1.64 \\pm 0.06, and A^B_1(0)/F^B_1(0) \\simeq 1.19 \\pm 0.03; combined with the ``world average" value of f^B_+(0) or/and F^B_1(0), these ratios lead to...

Critical heat flux experiments in a circular tube with heavy water and light water. (AWBA Development Program)

International Nuclear Information System (INIS)

Williams, C.L.; Beus, S.G.

1980-05-01

Experiments were performed to establish the critical heat flux (CHF) characteristics of heavy water and light water. Testing was performed with the up-flow of heavy and of light water within a 0.3744 inch inside diameter circular tube with 72.3 inches of heated length. Comparisons were made between heavy water and light water critical heat flux levels for the same local equilibrium quality at CHF, operating pressure, and nominal mass velocity. Results showed that heavy water CHF values were, on the average, 8 percent below the light water CHF values

Light and Heavy Tactical Wheeled Vehicle Fuel Consumption Evaluations Using Fuel Efficient Gear Oils (FEGO)

Science.gov (United States)

2016-05-01

UNCLASSIFIED LIGHT AND HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FUEL EFFICIENT GEAR OILS (FEGO) FINAL... HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FUEL EFFICIENT GEAR OILS (FEGO) FINAL REPORT TFLRF No. 477 by Adam C...August 2014 – March 2016 4. TITLE AND SUBTITLE LIGHT AND HEAVY TACTICAL WHEELED VEHICLE FUEL CONSUMPTION EVALUATIONS USING FEUL EFFICIENT GEAR OILS

A survey of light-vehicle driver education curriculum on sharing the road with heavy vehicles.

Science.gov (United States)

Baker, Stephanie; Schaudt, William A; Freed, J C; Toole, Laura

2012-07-01

Light-vehicle driver education programs that contain content about sharing the road with heavy vehicles may be helpful in reducing future light-vehicle/heavy-vehicle interactions. However, the extent of curricula in the United States including such content is unclear. Researchers developed an online survey targeted at instructors/administrators of state driver education programs to identify curricula addressing heavy vehicles and to determine perceived effectiveness. Ninety-one percent of respondents indicated that the light-vehicle driver education curriculum they teach/administer included a component covering how to safely share the road with heavy vehicles (82% perceived this component to be effective). Although a large proportion of these programs included a component on how to safely share the road with heavy vehicles, participants indicated there may be room for improvement. Participants recommended that future improvements to driver education programs include updated materials and student hands-on experience with heavy vehicles. Copyright © 2012 Elsevier Ltd. All rights reserved.

Hydrocracking of heavy ends to light hydrocarbons for steam-crackers feed

Energy Technology Data Exchange (ETDEWEB)

Cesana, A.; Buzzoni, R. [Eni S.p.A., Research Centre for Non-Conventional Energies, Novara (Italy). Ist. Eni Donegani

2010-12-30

Low value aromatic fractions, i.e. heavy pygas and pyrolysis fuel oil from naphtha steamcrackers or heavy distillates and ends from refinery, can be conveniently upgraded as high quality steamcracker feeds by severe hydrocracking treatment at 450 -530 C, 6 MPa H{sub 2} employing Ni-Mo or Zn-Mo on H-USY zeolite as catalysts. The process mainly leads to linear C{sub 2}-C{sub 4} alkanes with a low yield to CH{sub 4}. The robust catalytic system allows upgrading fractions with a high content of sulfur and nitrogen. Catalyst life and industrial feasibility have been assessed by long life runs using genuine industrial feedstocks. (orig.)

Standards for heavy water concentration determinations in light water

International Nuclear Information System (INIS)

Varlam, M.; Steflea, D.; Pavelescu, M.

1995-01-01

The paper presents a method to prepare heavy water -light water standards within the range 144 ppm - 1%. A formula for computing standards concentration based on initial concentration of D 2 O and distilled water is given

Fragmentation in central collisions of heavy systems

International Nuclear Information System (INIS)

Claesson, G.; Doss, K.G.R.; Ferguson, R.

1987-01-01

One of the goals of heavy ion reaction studies is to understand the fragmentation of hot nuclei. The LBL/GSI Plastic Ball detector system has been used to achieve a very high solid angle for detection of light and medium-heavy fragments emitted in 200 Mev/A Au + Au and Au + Fe reactions. The simultaneous measurement of almost all of the nucleons and nuclei resulting from each collision allows an estimation of the total charged particle multiplicity and hence the impact parameter. By choosing subsets of the data corresponding to a peripheral or central collision, the assumptions inherent in various models of nuclear fragmentation can be tested. 3 refs., 3 figs

Lattice results for heavy light matrix elements

International Nuclear Information System (INIS)

Soni, A.

1994-09-01

Lattice results for heavy light matrix elements are reviewed and some of their implications are very briefly discussed. Despite the fact that in most cases the lattice results for weak matrix elements at the moment have only a modest accuracy of about 20--30% they already have important phenomenological repercussions; e.g. for V td /V ts , x s /x d and B → K*γ

''Heavy light bullets'' in electron-positron plasma

International Nuclear Information System (INIS)

Berezhiani, V.I.; Mahajan, S.M.

1995-03-01

The nonlinear propagation of circularly polarized electromagnetic waves with relativistically strong amplitudes in an unmagnetized hot electron-positron plasma with a small fraction of ions is investigated. The possibility of finding localized solutions in such a plasma is explored. It is shown that these plasmas support the propagation of ''heavy light bullets''; nondiffracting and nondispersive electromagnetic (EM) pulses with large density bunching. (author). 24 refs, 12 figs

In vivo detection of the toxic heavy elements, lead and cadmium

International Nuclear Information System (INIS)

Thomas, B.J.; Thomas, B.W.; Davey, J.F.; Baddeley, H.; Summers, V.; Craswell, P.

1986-01-01

Portable systems for the in vivo measurement of the toxic heavy elements, cadmium and lead are described. The cadmium concentration in either the liver or left kidney is determined using a technique of thermal neutron capture gamma-ray analysis. X-ray fluorescence analysis is used to measure lead within the bone of the second phalanx of the index finger. Each of the measurements is used as an index of long term exposure to the element and applied to screening of exposed industrial workers. The results of these industrial health applications are presented. Clinical application of the measurements to the study of the involvement of these elements in renal disease is described in brief. (author)

Role of zero modes in the canonical quantization of heavy-fermion QED in light-cone coordinates

International Nuclear Information System (INIS)

Brown, R.W.; Jun, J.W.; Shvartsman, S.M.; Taylor, C.C.

1993-01-01

Four-dimensional heavy-fermion QED is studied in light-cone coordinates with (anti)periodic field boundary conditions. We carry out a consistent light-cone canonical quantization of this model using the Dirac algorithm for a system with first- and second-class constraints. To examine the role of the zero modes, we consider the quantization procedure in the zero-mode and the nonzero-mode sectors separately. In both sectors we obtain the physical variables and their canonical commutation relations. The physical Hamiltonian is constructed via a step-by-step exclusion of the unphysical degrees of freedom. An example using this Hamiltonian in which the zero modes play a role is the verification of the correct Coulomb potential between two heavy fermions

Acquired cutis laxa associated with light and heavy chain deposition disease

Directory of Open Access Journals (Sweden)

Reena A Majithia

2018-01-01

Full Text Available Acquired cutis laxa (ACL is a rare connective tissue disorder characterized by pendulous and coarsely wrinkled skin. There have been few cases of its association to monoclonal immunoglobulin deposition disease (MIDD, which constitutes the light chain (LCDD, heavy chain (HCDD, and light and heavy chain (LHCDD deposition disease. MIDD predominantly involves the kidney. Skin is the next common organ to be affected by HCDD, which presents as ACL. We report the case of a 40-year-old male who presented with ACL associated with LHCDD. The clinical features of ACL in the present case appeared prior to the development of clinical features related to LHCDD.

Large mixing of light and heavy neutrinos in seesaw models and the LHC

International Nuclear Information System (INIS)

He Xiaogang; Oh, Sechul; Tandean, Jusak; Wen, C.-C.

2009-01-01

In the type-I seesaw model the size of mixing between light and heavy neutrinos, ν and N, respectively, is of order the square root of their mass ratio, (m ν /m N ) 1/2 , with only one generation of the neutrinos. Since the light-neutrino mass must be less than an eV or so, the mixing would be very small, even for a heavy-neutrino mass of order a few hundred GeV. This would make it unlikely to test the model directly at the LHC, as the amplitude for producing the heavy neutrino is proportional to the mixing size. However, it has been realized for some time that, with more than one generation of light and heavy neutrinos, the mixing can be significantly larger in certain situations. In this paper we explore this possibility further and consider specific examples in detail in the context of type-I seesaw. We study its implications for the single production of the heavy neutrinos at the LHC via the main channel qq ' →W*→lN involving an ordinary charged lepton l. We then extend the discussion to the type-III seesaw model, which has richer phenomenology due to presence of the charged partners of the heavy neutrinos, and examine the implications for the single production of these heavy leptons at the LHC. In the latter model the new kinds of solutions that we find also make it possible to have sizable flavor-changing neutral-current effects in processes involving ordinary charged leptons.

Biochemical and morphological characterization of light and heavy sarcoplasmic reticulum vesicles. Volume I

Energy Technology Data Exchange (ETDEWEB)

Campbell, Kevin Peter [Univ. of Rochester, NY (United States)

1978-01-01

Light (30 to 32.5% sucrose) and heavy (38.5 to 42% sucrose) sarcoplasmic reticulum vesicles (LSR, HSR) were isolated from rabbit leg muscle. They were then diluted and washed with sucrose or KCl and referred to as sucrose or KCl washed vesicles. Thin-section electron microscopy of LSR vesicles reveals empty vesicles of various sizes and shapes where as the HSR vesicles appear as rounded vesicles of uniform size filled with electron dense material. The LSR consists of predominantly Ca²⁺ + Mg²⁺ ATPase (80 to 90%), a small amount of the high affinity Ca binding protein (5%), and a 5000 dalton proteolipid. The sucrose HSR vesicles contain the Ca²⁺ + Mg²⁺ ATPase (50%), Calsequestrin (25%), high affinity Ca binding protein (5%), one extrinsic 34,000 dalton protein (3%), one intrinsic 30,000 dalton protein (3%), a 9000 dalton proteolipid, and a 5000 dalton proteolipid. The sucrose--washed HSR vesicles contain greater than three times the calcium content of the sucrose washed LSR vesicles where as the KCl--washed vesicles contain less than 15 nmoles Ca²⁺ mg of protein each. The light and heavy sarcoplasmic reticulum vesicles were both able to accumulate calcium in the presence of ATP. Exchange of methanesulfonate for chloride resulted in the release of calcium from both the light and heavy SR vesicles. Sucrose causes a slight inhibition of chloride--induced calcium release from the heavy SR vesicles but it greatly reduces the release of calcium from the light SR vesicles. Sodium dantrolene (20 uM) has no effect on the release of calcium from the light SR vesicles but it inhibits the release of calcium from the heavy SR vesicles. The results indicate that the chloride--induced release of calcium may be acting by two mechanisms, osmotic swelling and depolarization.

Biochemical and morphological characterization of light and heavy sarcoplasmic reticulum vesicles. Volume I

International Nuclear Information System (INIS)

Campbell, K.P.

1978-01-01

Light (30 to 32.5% sucrose) and heavy (38.5 to 42% sucrose) sarcoplasmic reticulum vesicles (LSR, HSR) were isolated from rabbit leg muscle. They were then diluted and washed with sucrose or KCl and referred to as sucrose or KCl washed vesicles. Thin-section electron microscopy of LSR vesicles reveals empty vesicles of various sizes and shapes where as the HSR vesicles appear as rounded vesicles of uniform size filled with electron dense material. The LSR consists of predominantly Ca 2+ + Mg 2+ ATPase (80 to 90%), a small amount of the high affinity Ca binding protein (5%), and a 5000 dalton proteolipid. The sucrose HSR vesicles contain the Ca 2+ + Mg 2+ ATPase (50%), Calsequestrin (25%), high affinity Ca binding protein (5%), one extrinsic 34,000 dalton protein (3%), one intrinsic 30,000 dalton protein (3%), a 9000 dalton proteolipid, and a 5000 dalton proteolipid. The sucrose--washed HSR vesicles contain greater than three times the calcium content of the sucrose washed LSR vesicles where as the KCl--washed vesicles contain less than 15 nmoles Ca 2+ /mg of protein each. The light and heavy sarcoplasmic reticulum vesicles were both able to accumulate calcium in the presence of ATP. Exchange of methanesulfonate for chloride resulted in the release of calcium from both the light and heavy SR vesicles. Sucrose causes a slight inhibition of chloride--induced calcium release from the heavy SR vesicles but it greatly reduces the release of calcium from the light SR vesicles. Sodium dantrolene (20 uM) has no effect on the release of calcium from the light SR vesicles but it inhibits the release of calcium from the heavy SR vesicles. The results indicate that the chloride--induced release of calcium may be acting by two mechanisms, osmotic swelling and depolarization

Results from a prototype MAPS sensor telescope and readout system with zero suppression for the heavy flavor tracker at STAR

International Nuclear Information System (INIS)

Greiner, L.; Matis, H.S.; Ritter, H.G.; Rose, A.; Stezelberger, T.; Sun, X.; Szelezniak, M.; Thomas, J.; Vu, C.; Wieman, H.

2008-01-01

We describe a three Mimostar-2 Monolithic Active Pixel Sensor (MAPS) sensor telescope prototype with an accompanying readout system incorporating on-the-fly data sparsification. The system has been characterized and we report on the measured performance of the sensor telescope and readout system in beam tests conducted both at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory (LBNL) and in the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). This effort is part of the development and prototyping work that will lead to a vertex detector for the STAR experiment

New evaluation of thermal neutron scattering libraries for light and heavy water

Directory of Open Access Journals (Sweden)

Marquez Damian Jose Ignacio

2017-01-01

Full Text Available In order to improve the design and safety of thermal nuclear reactors and for verification of criticality safety conditions on systems with significant amount of fissile materials and water, it is necessary to perform high-precision neutron transport calculations and estimate uncertainties of the results. These calculations are based on neutron interaction data distributed in evaluated nuclear data libraries. To improve the evaluations of thermal scattering sub-libraries, we developed a set of thermal neutron scattering cross sections (scattering kernels for hydrogen bound in light water, and deuterium and oxygen bound in heavy water, in the ENDF-6 format from room temperature up to the critical temperatures of molecular liquids. The new evaluations were generated and processable with NJOY99 and also with NJOY-2012 with minor modifications (updates, and with the new version of NJOY-2016. The new TSL libraries are based on molecular dynamics simulations with GROMACS and recent experimental data, and result in an improvement of the calculation of single neutron scattering quantities. In this work, we discuss the importance of taking into account self-diffusion in liquids to accurately describe the neutron scattering at low neutron energies (quasi-elastic peak problem. To improve modeling of heavy water, it is important to take into account temperature-dependent static structure factors and apply Sköld approximation to the coherent inelastic components of the scattering matrix. The usage of the new set of scattering matrices and cross-sections improves the calculation of thermal critical systems moderated and/or reflected with light/heavy water obtained from the International Criticality Safety Benchmark Evaluation Project (ICSBEP handbook. For example, the use of the new thermal scattering library for heavy water, combined with the ROSFOND-2010 evaluation of the cross sections for deuterium, results in an improvement of the C/E ratio in 48 out of

New evaluation of thermal neutron scattering libraries for light and heavy water

Science.gov (United States)

Marquez Damian, Jose Ignacio; Granada, Jose Rolando; Cantargi, Florencia; Roubtsov, Danila

2017-09-01

In order to improve the design and safety of thermal nuclear reactors and for verification of criticality safety conditions on systems with significant amount of fissile materials and water, it is necessary to perform high-precision neutron transport calculations and estimate uncertainties of the results. These calculations are based on neutron interaction data distributed in evaluated nuclear data libraries. To improve the evaluations of thermal scattering sub-libraries, we developed a set of thermal neutron scattering cross sections (scattering kernels) for hydrogen bound in light water, and deuterium and oxygen bound in heavy water, in the ENDF-6 format from room temperature up to the critical temperatures of molecular liquids. The new evaluations were generated and processable with NJOY99 and also with NJOY-2012 with minor modifications (updates), and with the new version of NJOY-2016. The new TSL libraries are based on molecular dynamics simulations with GROMACS and recent experimental data, and result in an improvement of the calculation of single neutron scattering quantities. In this work, we discuss the importance of taking into account self-diffusion in liquids to accurately describe the neutron scattering at low neutron energies (quasi-elastic peak problem). To improve modeling of heavy water, it is important to take into account temperature-dependent static structure factors and apply Sköld approximation to the coherent inelastic components of the scattering matrix. The usage of the new set of scattering matrices and cross-sections improves the calculation of thermal critical systems moderated and/or reflected with light/heavy water obtained from the International Criticality Safety Benchmark Evaluation Project (ICSBEP) handbook. For example, the use of the new thermal scattering library for heavy water, combined with the ROSFOND-2010 evaluation of the cross sections for deuterium, results in an improvement of the C/E ratio in 48 out of 65

Hyperfine splitting of low-lying heavy baryons

Energy Technology Data Exchange (ETDEWEB)

Harada, M.; Qamar, A.; Schechter, J. [Syracuse Univ., NY (United States). Dept. of Physics; Sannino, F. [Syracuse Univ., NY (United States). Dept. of Physics]|[Dipartimento di Scienze Fisiche and Istituto Nazionale di Fisica Nucleare, Mostra D`Oltremare Pad. 19, 80125, Napoli (Italy); Weigel, H. [Institute for Theoretical Physics, Tuebingen University, Auf der Morgenstelle 14, D-72076, Tuebingen (Germany)

1997-11-10

We calculate the next-to-leading order contribution to the masses of the heavy baryons in the bound-state approach for baryons containing a heavy quark. These 1/N{sub C} corrections arise when states of good spin and isospin are generated from the background soliton of the light meson fields. Our study is motivated by the previously established result that light vector meson fields are required for this soliton in order to reasonably describe the spectrum of both the light and the heavy baryons. We note that the inclusion of light vector mesons significantly improves the agreement of the predicted hyperfine splitting with experiment. A number of aspects of this somewhat complicated calculation are discussed in detail. (orig.). 33 refs.

ZIRCONIUM—HAFNIUM ISOTOPE EVIDENCE FROM METEORITES FOR THE DECOUPLED SYNTHESIS OF LIGHT AND HEAVY NEUTRON-RICH NUCLEI

Energy Technology Data Exchange (ETDEWEB)

Akram, W.; Schönbächler, M. [School of Earth, Atmospheric and Environmental Sciences, The University of Manchester, Oxford Road, Manchester, M13 9PL (United Kingdom); Sprung, P. [Institut für Planetologie, Universität Münster, Wilhelm-Klemm-Strasse 10, D-48149 Münster (Germany); Vogel, N. [Institute for Geochemistry and Petrology, ETH, Clausiusstrasse 25, 8092 Zürich (Switzerland)

2013-11-10

Recent work based on analyses of meteorite and terrestrial whole-rock samples showed that the r- and s- process isotopes of Hf were homogeneously distributed throughout the inner solar system. We report new Hf isotope data for Calcium-Aluminum-rich inclusions (CAIs) of the CV3 carbonaceous chondrite Allende, and novel high-precision Zr isotope data for these CAIs and three carbonaceous chondrites (CM, CO, CK). Our Zr data reveal enrichments in the neutron-rich isotope {sup 96}Zr (≤1ε in {sup 96}Zr/{sup 90}Zr) for bulk chondrites and CAIs (∼2ε). Potential isotope effects due to incomplete sample dissolution, galactic and cosmic ray spallation, and the nuclear field shift are assessed and excluded, leading to the conclusion that the {sup 96}Zr isotope variations are of nucleosynthetic origin. The {sup 96}Zr enrichments are coupled with {sup 50}Ti excesses suggesting that both nuclides were produced in the same astrophysical environment. The same CAIs also exhibit deficits in r-process Hf isotopes, which provides strong evidence for a decoupling between the nucleosynthetic processes that produce the light (A ≤ 130) and heavy (A > 130) neutron-rich isotopes. We propose that the light neutron-capture isotopes largely formed in Type II supernovae (SNeII) with higher mass progenitors than the supernovae that produced the heavy r-process isotopes. In the context of our model, the light isotopes (e.g. {sup 96}Zr) are predominantly synthesized via charged-particle reactions in a high entropy wind environment, in which Hf isotopes are not produced. Collectively, our data indicates that CAIs sampled an excess of materials produced in a normal mass (12-25 M{sub ☉}) SNII.

Characterization of the interaction between the heavy and light chains of bovine factor Va.

Science.gov (United States)

Walker, F J

1992-10-05

Bovine factor Va has been previously been shown to consist of heavy (M(r) = 94,000) and light chains (M(r) = 81,000), that interact in a manner dependent upon the presence of either calcium or manganese ions. In an attempt to understand the mechanism of subunit interaction we have studied the effects of temperature and ions on factor Va stability. The rates of formation of factor Va from isolated chains and dissociation were temperature-dependent with an energy of activation of 6.2 and 1.3 kcal mol-1, respectively. The yield of factor Va from isolated chains was inversely related to the amount of time the chains were incubated at 4 degrees C. Incubation of individual chains revealed that the heavy chain is cold-labile, an effect that is reversible. Manganese ion was observed to prevent the conversion to the inactive form. High salt tends to stabilize the two-chain structure of factor Va, but is inhibitory to its formation from isolated chains. High concentrations of either manganese or calcium ions also inhibited reconstitution of activity. The light chain, in particular, was sensitive to the presence of manganese or calcium ion. Heavy chain that had been cleaved by activated protein C had a weakened interaction with the light chain, and the resulting complex had no procoagulant activity. Cooling of the heavy chain to 4 degrees C enhanced its intrinsic fluorescence. Manganese ion prevented some of this enhancement. The heavy chain fluorescence returned to the room temperature value with a half-life of approximately 10 min. In the presence of manganese ion relaxation was accelerated. The intrinsic fluorescence of activated protein C-cleaved heavy chain was not increased when the temperature was decreased. These data suggest that the heavy chain can exist in two forms. Elevated temperature converts it to a form that can bind ions and have a productive interaction with the light chain. However, conditions that prevent the heavy chain from combining with the light

A decade of heavy light

International Nuclear Information System (INIS)

Anon.

1993-01-01

Ten years ago, in May 1983, the UA1 experiment led by Carlo Rubbia at CERN's proton-antiproton collider saw the first Z particle, the heavy (91 GeV) electrically neutral carrier of the weak force. The press announced the discovery of 'heavy light', a highly apt description which has unfortunately fallen into disuse. The weak force comes in two varieties - one which permutes electric charges (the classic example being the beta decay of a neutron into a proton and an electron), and a neutral variant which does not. Each has its carrier particle, and both were discovered at CERN - first the charged W, in January 1983, and then the Z, a few months later. For both experiment and theory, the Z discovery was the culmination of a long and diligent quest without parallel in the history of modern physics. The missing piece of the 'electroweak' jigsaw finally clicked into place, and for ever after electromagnetism would be firmly linked with the weak nuclear force. It was the twentieth-century remake, with a much bigger cast, of the story which began in 1864 when James Clerk Maxwell wrote down his four famous equations linking electricity and magnetism. This was the birth of a new science - electromagnetism

Heavy Metals (Mercury, Lead and Cadmium Determination in 17 Species of Fish Marketed in Khorramabad City, West of Iran

Directory of Open Access Journals (Sweden)

Ali Mortazavi

2016-01-01

Full Text Available Heavy metals entrance to fish body tissues and transferring to human body systems after their consuming makes numerous undesirable effects and health problems. The aim of this study was to determine some heavy metals (lead, cadmium and mercury in fresh fishes marketed in Khorramabad City, west of Iran. In this descriptive study, five samples of 17 fish species with high consumption were purchased randomly in 2014. Measurement of mercury, lead and cadmium was performed using atomic absorption spectrometry. All measurements were performed three times for each sample. Lead mean levels in fish samples was in the range 0.736 -1.005 ppm, cadmium range was from 0.196 to 0.015 ppm and mean content of mercury was  0.431 - 0.107 ppm. At present mean concentration of lead, mercury and cadmium in supplied fishes muscle is lower than maximum recommended levels according to WHO, EC and FDA guidelines. Based on the obtained results of this study and the importance of heavy metals in foods and their impacts on human health, continuous monitoring of heavy metals levels in foods is necessary.

Heavy ion measurements at ATLAS and CMS

CERN Document Server

Chapon, Emilien

2018-01-01

We present an overview of recent results from the ATLAS and CMS collaborations on heavy ion physics. Using data from proton-proton, proton-lead and lead-lead collisions at the LHC, these results help to shed light on the properties of nuclear matter.

A natural scenario for heavy colored and light uncolored superpartners

International Nuclear Information System (INIS)

Bhattacharyya, Gautam; Bhattacherjee, Biplob; Yanagida, Tsutomu T.; Yokozaki, Norimi

2013-01-01

Influenced by the current trend of experimental data, especially from the LHC, we construct a supersymmetric scenario where a natural dynamics makes the squarks and gluino super-heavy (order 10 TeV) while keeping the sleptons and the weak gauginos light (100–500 GeV). The dynamics relies on the interfusion of two underlying ideas: (i) gauge mediation of supersymmetry breaking with two messenger multiplets, one transforming as a triplet of weak SU(2) and the other as an octet of color SU(3); (ii) perturbative gauge coupling unification at the string scale even with these incomplete SU(5) multiplets. Interestingly, the relative magnitude of the triplet and octet messenger scales that ensures gauge unification at the two-loop level also helps to naturally keep the uncolored superpartners light while making the colored ones heavy

Investigation of heavy metals (Cadmium, Lead in Chironomidae and Gammarus pulex Namrood River – Tehran Province

Directory of Open Access Journals (Sweden)

Rezaei M. Kamali A. and Shapoori M.

2012-01-01

Full Text Available Marine ecosystem pollution is one of the important problems of today environment. In this study the existence of heavy metal in the Namrood River, situated in Firoozkooh in Tehran province, Iran has been investigated. The Namrood River is located near Firoozkooh route, and is affected by pollutant from tourist centers, entertainment, gas stations, nearby villages’ sewage systems, farming effluent, and hatchery farms. In some areas, its water is heavily polluted possibly by heavy metals. After selecting two stations in upstream and downstream of the river, they were sampled three times in both cold and hot seasons of year (mid-March, and June for Chironomidae, and Gammarus plux sediments. The measured heavy metals were cadmium and lead. The results showed that the concentration of cadmium in measured samples varied from 0.010-0.2033 ppm. The concentration of lead in samples varied from 0.11-2.16 ppm. The results also indicated that sediments of samples taken from the upper station in the cold season had a higher proportion of cadmium and a higher concentration of lead  than  sediments in the lower station during the hot season.

Heavy-to-light form factors for non-relativistic bound states

International Nuclear Information System (INIS)

Bell, G.; Feldmann, Th.

2007-01-01

We investigate transition form factors between non-relativistic QCD bound states at large recoil energy. Assuming the decaying quark to be much heavier than its decay product, the relativistic dynamics can be treated according to the factorization formula for heavy-to-light form factors obtained from the heavy-quark expansion in QCD. The non-relativistic expansion determines the bound-state wave functions to be Coulomb-like. As a consequence, one can explicitly calculate the so-called 'soft-overlap' contribution to the transition form factor

A novel route for the removal of bodily heavy metal lead (II)

International Nuclear Information System (INIS)

Huang, Weirong; Zhang, Penghua; Xu, Hui; He, Yongju; Wang, Fei; Liang, Gaowei; Chang, Shengli

2015-01-01

The lead ion concentration in bile is considerably higher than in blood, and bile is released into the alimentary tract. Thiol-modified SBA-15 administered orally can combine with lead ions in the alimentary tract. In this paper, the in vitro lead absorption of bile was investigated. This thiol-modified SBA-15 material was used in pharmacodynamics studies on rabbits. The result that the lead content in faeces was notably higher indicates that thiol-modified SBA-15 can efficiently remove lead. The mechanism could include the following: thiol-modified SBA-15 material cuts off the heavy metal lead recirculation in the process of bile enterohepatic circulation by chelating the lead in the alimentary tract, causing a certain proportion of lead to be removed by the thiol mesoporous material, and the lead is subsequently egested out of the body in faeces. The results indicate that this material might be a potential non-injection material for the removal bodily heavy metal lead in the alimentary tract. This material may also be a useful means of lead removal, especially for non-acute sub-poisoning symptoms. (paper)

Renormalized sum rules for structure functions of heavy meson decays

International Nuclear Information System (INIS)

Grozin, A.G.; Korchemsky, G.P.

1996-01-01

We consider the properties of the structure functions of inclusive heavy meson decays B→X c and treat the c quark mass as a free parameter. We show that in two extreme cases of heavy and light c quarks the structure functions of heavy-heavy and heavy-light transitions are given by a Fourier transform of the matrix elements of Wilson lines containing a timelike and a lightlike segment, correspondingly. Using the renormalization properties of Wilson lines we find the dependence of the structure functions on the factorization scale, the structure function of the heavy-heavy transition is renormalized multiplicatively, while that of the heavy-light transition obeys the GLAP-type evolution equation. We propose a generalization of the sum rules for the moments of the structure functions (Bjorken, Voloshin, and the open-quote open-quote third close-quote close-quote sum rules) with a soft exponential factorization cutoff, which correctly incorporates both perturbative and nonperturbative effects. We analyze nonperturbative corrections by first considering infrared renormalon contributions to the Wilson lines. Uncertainties induced by the leading renormalon pole at u=1/2 are exactly canceled by a similar uncertainty in the heavy quark pole mass. The leading nonperturbative corrections associated with the next renormalon at u=1 are parametrized by the matrix element μ π 2 which is proportional to the heavy quark kinetic energy. copyright 1996 The American Physical Society

Impact of heavy metals on the female reproductive system

Directory of Open Access Journals (Sweden)

Piotr Rzymski

2015-05-01

Full Text Available Introduction. It has been recognized that environmental pollution can affect the quality of health of the human population. Heavy metals are among the group of highly emitted contaminants and their adverse effect of living organisms has been widely studied in recent decades. Lifestyle and quality of the ambient environment are among these factors which can mainly contribute to the heavy metals exposure in humans. Objective. A review of literature linking heavy metals and the female reproductive system and description of the possible associations with emission and exposure of heavy metals and impairments of female reproductive system according to current knowledge. Results. The potential health disorders caused by chronic or acute heavy metals toxicity include immunodeficiency, osteoporosis, neurodegeneration and organ failures. Potential linkages of heavy metals concentration found in different human organs and blood with oestrogen-dependent diseases such as breast cancer, endometrial cancer, endometriosis and spontaneous abortions, as well as pre-term deliveries, stillbirths and hypotrophy, have also been reported. Conclusions. Environmental deterioration can lead to the elevated risk of human exposure to heavy metals, and consequently, health implications including disturbances in reproduction. It is therefore important to continue the investigations on metal-induced mechanisms of fertility impairment on the genetic, epigenetic and biochemical level.

The Role of Zero-Modes in the Canonical Quantization of Heavy-Fermion QED in Light-Cone Coordinates

OpenAIRE

Brown, Robert W.; Jun, Jin Woo; Shvartsman, Shmaryu M.; Taylor, Cyrus C.

1993-01-01

Four-dimensional heavy-fermion QED is studied in light-cone coordinates with (anti-)periodic field boundary conditions. We carry out a consistent light-cone canonical quantization of this model using the Dirac algorithm for a system with first- and second-class constraints. To examine the role of the zero modes, we consider the quantization procedure in {the }zero-mode {and the non-zero-mode} sectors separately. In both sectors we obtain the physical variables and their canonical commutation ...

A triple telescope for the simultaneous identification of light and heavy reaction products

CERN Document Server

Moura, M M D; Alonso, E E; Souza, F A; Fujii, R J; Morais, O B D; Szanto, E M; Szanto de Toledo, A; Carlin, N

2001-01-01

Sixteen triple telescopes were developed to be used in the study of light heavy-ion nuclear reactions at the University of Sao Paulo Pelletron Laboratory, with the purpose of providing simultaneous identification of light and heavy reaction products. Each telescope consists of one ionization chamber, one Si detector and one CsI detector with photodiode readout. The telescopes are encapsulated in such a way that they can be utilized in different setup geometries depending on the kind of experiment being performed. Results for the ionization chambers energy loss resolution, Si and CsI detectors energy resolution and general performance are presented.

Two lighter than air systems in opposing flight regimes: An unmanned short haul, heavy load transport balloon and a manned, light payload airship

Science.gov (United States)

Pohl, R. A.

1975-01-01

Lighter Than Air vehicles are generally defined or categorized by the shape of the balloon, payload capacity and operational flight regime. Two balloon systems that are classed as being in opposite categories are described. One is a cable guided, helium filled, short haul, heavy load transport Lighter Than Air system with a natural shaped envelope. The other is a manned, aerodynamic shaped airship which utilizes hot air as the buoyancy medium and is in the light payload class. While the airship is in the design/fabrication phase with flight tests scheduled for the latter part of 1974, the transport balloon system has been operational for some eight years.

Heavy water upgrading system in the Fugen heavy water reactor

International Nuclear Information System (INIS)

Matsushita, T.; Susaki, S.

1980-01-01

The heavy water upgrading system, which is installed in the Fugen heavy water reactor (HWR) was designed to reuse degraded heavy water generated from the deuteration-dedeuteration of resin in the ion exchange column of the moderator purification system. The electrolysis method has been applied in this system on the basis of the predicted generation rate and concentration of degraded heavy water. The structural feature of the electrolytic cell is that it consists of dual cylindrical electrodes, instead of a diaphragm as in the case of conventional water electrolysis. 2 refs

The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

KAUST Repository

Chailyan, Anna

2011-06-28

The antigen-binding site of immunoglobulins is formed by six regions, three from the light and three from the heavy chain variable domains, which, on association of the two chains, form the conventional antigen-binding site of the antibody. The mode of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface between the heavy and light chain variable domains and show that there are essentially two different modes for their interaction that can be identified by the presence of key amino acids in specific positions of the antibody sequences. We also show that the different packing modes are related to the type of recognized antigen.

Light Higgs from Scalar See-Saw in Technicolor

DEFF Research Database (Denmark)

Foadi, Roshan; Frandsen, Mads Toudal

2012-01-01

We consider a TeV scale see-saw mechanism leading to light scalar resonances in models with otherwise intrinsically heavy scalars. The mechanism can provide a 125 GeV technicolor Higgs in e.g. two-scale TC models......We consider a TeV scale see-saw mechanism leading to light scalar resonances in models with otherwise intrinsically heavy scalars. The mechanism can provide a 125 GeV technicolor Higgs in e.g. two-scale TC models...

Heavy-light mesons in lattice HQET and QCD

International Nuclear Information System (INIS)

Guazzini, D.

2007-12-01

We present a study of a combination of HQET and relativistic QCD to extract the b-quark mass and the B s -meson decay constant from lattice quenched simulations. We start from a small volume, where one can directly simulate the b-quark, and compute the connection to a large volume, where finite size effects are negligible, through a finite size technique. The latter consists of steps extrapolated to the continuum limit, where the b-region is reached through interpolations guided by the effective theory. With the lattice spacing given in terms of the Sommer's scale r 0 and the experimental B s and K masses, we get the final results for the renormalization group invariant mass M b =6.88(10) GeV, translating into anti m b (anti m b )=4.42(6) GeV in the MS scheme, and f B s =191(6) MeV for the decay constant. A renormalization condition for the chromo-magnetic operator, responsible, at leading order in the heavy quark mass expansion of HQET, for the mass splitting between the pseudoscalar and the vector channel in mesonic heavy-light bound states, is provided in terms of lattice correlations functions which well suits a non-perturbative computation involving a large range of renormalization scales and no valence quarks. The two-loop expression of the corresponding anomalous dimension in the Schroedinger functional (SF) scheme is computed starting from results in the literature; it requires a one-loop calculation in the SF scheme with a non-vanishing background field. The cutoff effects affecting the scale evolution of the renormalization factors are studied at one-loop order, and confirmed by non-perturbative quenched computations to be negligible for the numerical precision achievable at present. (orig.)

Heavy-light mesons in lattice HQET and QCD

Energy Technology Data Exchange (ETDEWEB)

Guazzini, D.

2007-12-15

We present a study of a combination of HQET and relativistic QCD to extract the b-quark mass and the B{sub s}-meson decay constant from lattice quenched simulations. We start from a small volume, where one can directly simulate the b-quark, and compute the connection to a large volume, where finite size effects are negligible, through a finite size technique. The latter consists of steps extrapolated to the continuum limit, where the b-region is reached through interpolations guided by the effective theory. With the lattice spacing given in terms of the Sommer's scale r{sub 0} and the experimental B{sub s} and K masses, we get the final results for the renormalization group invariant mass M{sub b}=6.88(10) GeV, translating into anti m{sub b}(anti m{sub b})=4.42(6) GeV in the MS scheme, and f{sub B{sub s}}=191(6) MeV for the decay constant. A renormalization condition for the chromo-magnetic operator, responsible, at leading order in the heavy quark mass expansion of HQET, for the mass splitting between the pseudoscalar and the vector channel in mesonic heavy-light bound states, is provided in terms of lattice correlations functions which well suits a non-perturbative computation involving a large range of renormalization scales and no valence quarks. The two-loop expression of the corresponding anomalous dimension in the Schroedinger functional (SF) scheme is computed starting from results in the literature; it requires a one-loop calculation in the SF scheme with a non-vanishing background field. The cutoff effects affecting the scale evolution of the renormalization factors are studied at one-loop order, and confirmed by non-perturbative quenched computations to be negligible for the numerical precision achievable at present. (orig.)

Adsorption by and artificial release of zinc and lead from porous concrete for recycling of adsorbed zinc and lead and of porous concrete to reduce urban non-point heavy metal runoff.

Science.gov (United States)

Harada, Shigeki; Yanbe, Miyu

2018-04-01

This report describes the use of porous concrete at the bottom of a sewage trap to prevent runoff of non-point heavy metals into receiving waters, and, secondarily, to reduce total runoff volume during heavy rains in urbanized areas while simultaneously increasing the recharge volume of heavy-metal-free water into underground aquifers. This idea has the advantage of preventing clogging, which is fundamentally very important when using pervious materials. During actual field experiments, two important parameters were identified: maximum adsorption weight of lead and zinc by the volume of porous concrete, and heavy metal recovery rate by artificial acidification after adsorption. To understand the effect of ambient heavy metal concentration, a simple mixing system was used to adjust the concentrations of lead and zinc solutions. The concrete blocks used had been prepared for a previous study by Harada & Komuro (2010). The results showed that maximum adsorption depended on the ambient concentration, expressed as the linear isothermal theory, and that recovery depended on the final pH value (0.5 or 0.0). The dependence on pH is very important for recycling the porous concrete. A pH of 0.5 is important for recycling both heavy metals, especially zinc, (8.0-22.1% of lead and 42-74% of zinc) and porous concrete because porous concrete has not been heavily damaged by acid. However, at a pH of 0.0, the heavy metals could be recovered: 30-60% of the lead and 75-125% of the zinc. At a higher pH, such as 2.0, no release of heavy metals occurred, indicating the safety to the environment of using porous concrete, because the lowest recorded pH of rainfall in Japan is. 4.0. Copyright © 2018 Elsevier Ltd. All rights reserved.

Distribution of light and heavy fractions of soil organic carbon as related to land use and tillage practice

Science.gov (United States)

Tan, Zhengxi; Lal, R.; Owens, L.; Izaurralde, R. C.

2007-01-01

Mass distributions of different soil organic carbon (SOC) fractions are influenced by land use and management. Concentrations of C and N in light- and heavy fractions of bulk soils and aggregates in 0–20 cm were determined to evaluate the role of aggregation in SOC sequestration under conventional tillage (CT), no-till (NT), and forest treatments. Light- and heavy fractions of SOC were separated using 1.85 g mL−1 sodium polytungstate solution. Soils under forest and NT preserved, respectively, 167% and 94% more light fraction than those under CT. The mass of light fraction decreased with an increase in soil depth, but significantly increased with an increase in aggregate size. C concentrations of light fraction in all aggregate classes were significantly higher under NT and forest than under CT. C concentrations in heavy fraction averaged 20, 10, and 8 g kg−1 under forest, NT, and CT, respectively. Of the total SOC pool, heavy fraction C accounted for 76% in CT soils and 63% in forest and NT soils. These data suggest that there is a greater protection of SOC by aggregates in the light fraction of minimally disturbed soils than that of disturbed soil, and the SOC loss following conversion from forest to agriculture is attributed to reduction in C concentrations in both heavy and light fractions. In contrast, the SOC gain upon conversion from CT to NT is primarily attributed to an increase in C concentration in the light fraction.

Spin alignment in heavy and light flavour systems at OPAL

CERN Document Server

Robins, Simon

1999-01-01

Spin alignment of inclusive vector mesons and longitudinal polarization of Lambda hyperons have been measured in a sample of 4.3 million hadronic Z/sup 0/ decays from the OPAL detector at LEP. Leading, light vector mesons have been $9 found to populate preferentially the helicity-zero state, a result which has no firm theoretical explanation. The values of off-diagonal elements of the helicity density matrix are in agreement with a theory based on the Standard $9 Model with coherent fragmentation. The longitudinal polarization of the Lambda is well described by a model in which the constituent strange quark carries all of the hyperon spin.

Shorter Exciton Lifetimes via an External Heavy-Atom Effect: Alleviating the Effects of Bimolecular Processes in Organic Light-Emitting Diodes.

Science.gov (United States)

Einzinger, Markus; Zhu, Tianyu; de Silva, Piotr; Belger, Christian; Swager, Timothy M; Van Voorhis, Troy; Baldo, Marc A

2017-10-01

Multiexcited-state phenomena are believed to be the root cause of two exigent challenges in organic light-emitting diodes; namely, efficiency roll-off and degradation. The development of novel strategies to reduce exciton densities under heavy load is therefore highly desirable. Here, it is shown that triplet exciton lifetimes of thermally activated delayed-fluorescence-emitter molecules can be manipulated in the solid state by exploiting intermolecular interactions. The external heavy-atom effect of brominated host molecules leads to increased spin-orbit coupling, which in turn enhances intersystem crossing rates in the guest molecule. Wave function overlap between the host and the guest is confirmed by combined molecular dynamics and density functional theory calculations. Shorter triplet exciton lifetimes are observed, while high photoluminescence quantum yields and essentially unaltered emission spectra are maintained. A change in the intersystem crossing rate ratio due to increased dielectric constants leads to almost 50% lower triplet exciton densities in the emissive layer in the steady state and results in an improved onset of the photoluminescence quantum yield roll-off at high excitation densities. Efficient organic light-emitting diodes with better roll-off behavior based on these novel hosts are fabricated, demonstrating the suitability of this concept for real-world applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Monitoring light source for CMS lead tungstate crystal calorimeter at LHC

CERN Document Server

Zhang Li Yuan; Zhu Ren Yuan; Liu Dun Can

2000-01-01

Light monitoring will serve as an inter calibration for CMS lead tungstate crystals in situ at LHC, which is crucial for maintaining crystal calorimeter's sub percent constant term in the energy resolution. This paper presents the design of the CMS ECAL monitoring light source and high level distribution system. The correlations between variations of the light output and the transmittance for the CMS choice of Y doped PbWO//4 crystals were investigated, and were used to study monitoring linearity and sensitivity as a function of the wavelength. The monitoring wavelength was determined so that a good linearity as well as adequate sensitivity can be achieved. The performance of a custom manufactured tunable laser system is presented. Issues related to monitoring precision are discussed. 29 Refs.

Concentrations of heavy metals (lead, manganese, cadmium) in blood and urine of former uranium workers

International Nuclear Information System (INIS)

Apostolova, D.; Pavlova, S.; Paskalev, Z.

1999-01-01

Uranium ores contain heavy metals and other stable chemical elements as oxides, hydro-carbonates, sulphates, etc. During chemical processing of ore they could be transformed into compounds soluble in biologic liquids. The purpose of this study was to determine the combined intoxication of uranium miners and millers by heavy metals and radiation. Heavy metal (lead, manganese and cadmium) concentrations in blood and urine od 149 former uranium miners and millers were determined by AAS method. Data of significantly increased lead and manganese concentration in blood (p<0.05) of two groups were established in comparison with a control group. There is no statistical significant differences in the cadmium concentrations. The lead and manganese blood levels at the uranium millers were significant higher than those of the uranium miner group (p<0.05). Tendency towards increased blood lead concentrations of uranium millers depending on the length of service was established

MSSM interpretations of the LHC discovery. Light or heavy Higgs?

Energy Technology Data Exchange (ETDEWEB)

Bechtle, P.; Stefaniak, T. [Bonn Univ. (Germany). Physikalisches Inst.; Heinemeyer, S. [Instituto de Fisica de Cantabria (CSIC-UC), Santander (Spain); Staal, O. [Stockholm Univ. (Sweden). The Oskar Klein Centre; Weiglein, G.; Zeune, L. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

2012-11-15

A Higgs-like particle with a mass of about 126 GeV has been discovered at the LHC. Within the experimental uncertainties, the measured properties of this new state are compatible with those of the Higgs boson in the Standard Model (SM). While not statistically significant at present, the results show some interesting patterns of deviations from the SM predictions, in particular a higher rate in the {gamma}{gamma} decay mode observed by ATLAS and CMS, and a somewhat smaller rate in the {tau}{sup +}{tau}{sup -} mode. The LHC discovery is also compatible with the predictions of the Higgs sector of the Minimal Supersymmetric Standard Model (MSSM), interpreting the new state as either the light or the heavy CP-even MSSM Higgs boson. Within the framework of the MSSM with seven free parameters (pMSSM-7), we fit the various rates of cross section times branching ratio as measured by the LHC and Tevatron experiments under the hypotheses of either the light or the heavy CP-even Higgs boson being the new state around 126 GeV, with and without the inclusion of further lowenergy observables. We find an overall good quality of the fits, with the best fit points exhibiting an enhancement of the {gamma}{gamma} rate, as well as a small suppression of the b anti b and {tau}{sup +}{tau}{sup -} channels with respect to their SM expectations, depending on the details of the fit. For the fits including the whole data set the light CP-even Higgs interpretation in the MSSM results in a higher relative fit probability than the SM fit. On the other hand, we find that the present data also permit the more exotic interpretation in terms of the heavy CP-even MSSM Higgs, which could give rise to experimental signatures of additional Higgs states in the near future.

Matching of heavy-light flavour currents between HQET at order 1/m and QCD

DEFF Research Database (Denmark)

Della Morte, Michele; Dooling, Samantha; Heitger, Jochen

2014-01-01

We present a strategy how to match the full set of components of the heavy-light axial and vector currents in Heavy Quark Effective Theory (HQET), up to and including 1/m-corrections, to QCD. While the ultimate goal is to apply these matching conditions non-perturbatively, in this study we first...

Measurement of Leading Particle Effects in Decays of Z0 Bosons into Light Flavors

International Nuclear Information System (INIS)

Steiner, R.; Benvenuti, A.; Coller, J.; Hedges, S.; Johnson, A.; Shank, J.; Whitaker, J.; Allen, N.; Cotton, R.; Dervan, P.; Hasan, A.; McKemey, A.; Watts, S.; Caldwell, D.; Lu, A.; Yellin, S.; Cavalli-Sforza, M.; Coyne, D.; Fernandez, J.; Liu, X.; Reinertsen, P.; Schalk, T.; Schumm, B.; Williams, D.; DOliveira, A.; Johnson, R.; Meadows, B.; Nussbaum, M.; Dima, M.; Harton, J.; Smy, M.; Wilson, R.; Baranko, G.; Fahey, S.; Fan, C.; Krishna, N.; Lauber, J.; Nauenberg, U.; Wagner, D.; Bazarko, A.; Bolton, T.; Rowson, P.; Shaevitz, M.; Camanzi, B.; Mazzucato, E.; Piemontese, L.; Calcaterra, A.; De Sangro, R.; Peruzzi, I.; Piccolo, M.; Eisenstein, B.; Gladding, G.; Karliner, I.; Shapiro, G.; Steiner, H.; Bardon, O.; Burrows, P.; Busza, W.; Cowan, R.; Dong, D.; Fero, M.; Gonzalez, S.; Kendall, H.; Lath, A.; Lia, V.; Osborne, L.; Quigley, J.; Taylor, F.; Torrence, E.; Verdier, R.; Williams, D.; Yamamoto, R.; Yamartino, J.

1997-01-01

We present evidence for leading particle production in hadronic decays of the Z 0 boson to light-flavor jets. A polarized electron beam was used to tag quark and antiquark jets, and a vertex detector was employed to reject heavy-flavor events. Charged hadrons were identified with a Cherenkov ring imaging detector. In the quark jets, more high-momentum p, L, K - , and bar K *0 were observed than their antiparticles, and vice versa for antiquark jets, providing direct evidence that the higher-momentum particles in jets are more likely to carry the primary quark or antiquark from the Z 0 decay, and that s bar s production is suppressed in fragmentation. copyright 1997 The American Physical Society

Nonthermal plasma reactors for the production of light hydrocarbon olefins from heavy oil

Directory of Open Access Journals (Sweden)

G. Prieto

2003-03-01

Full Text Available During the last decade, nonthermal plasma technology was applied in many different fields, focusing attention on the destruction of harmful compounds in the air. This paper deals with nonthermal plasma reactors for the conversion of heavy oil into light hydrocarbon olefins, to be employed as gasoline components or to be added in small amounts for the catalytic reduction of nitrogen oxide compounds in the treatment of exhaust gas at power plants. For the process, the plate-plate nonthermal plasma reactor driven by AC high voltage was selected. The reactor was modeled as a function of parameter characteristics, using the methodology provided by the statistical experimental design. The parameters studied were gap distance between electrodes, carrier gas flow and applied power. Results indicate that the reactions occurring in the process of heavy oil conversion have an important selective behavior. The products obtained were C1-C4 hydrocarbons with ethylene as the main compound. Operating the parameters of the reactor within the established operative window of the system and close to the optimum conditions, efficiencies as high as 70 (mul/joule were obtained. These values validate the process as an in-situ method to produce light olefins for the treatment of nitrogen oxides in the exhaust gas from diesel engines.

Heavy Quark Impact Factor at Next-to-leading Level

OpenAIRE

Ciafaloni, Marcello; Rodrigo, German

2000-01-01

We further analyze the definition and the calculation of the heavy quark impact factor at next-to-leading (NL) log(s) level, and we provide its analytical expression in a previously proposed k-factorization scheme. Our results indicate that k-factorization holds at NL level with a properly chosen energy scale, and with the same gluonic Green's function previously found in the massless probe case.

Light charged particle emission in heavy-ion reactions – What have ...

Indian Academy of Sciences (India)

coincidence with gamma rays, fission products, evaporation residues have yielded interesting results which bring out the influence of nuclear structure, nuclear mean field and dynamics on the emission of these particles. Keywords. Light charged particles; heavy-ion induced reactions; particle spectra and angular distri-.

Asymmetries in heavy meson production from light quark fragmentation

International Nuclear Information System (INIS)

Dias de Deus, J.; Duraes, F.

2000-01-01

We discuss the possibility of the asymmetry in D - /D + production from π - beams, being a direct consequence of the properties of the light quark fragmentation function into heavy mesons. The main features of the asymmetry, as a function of x F , are easily described. An integrated sum rule for the D - , D + multiplicity difference is presented. Predictions for the asymmetry in B meson production are given. (orig.)

Energy utilization of light and heavy weaned piglets subjected to different dietary energy levels

Directory of Open Access Journals (Sweden)

Andréa Machado Leal Ribeiro

Full Text Available ABSTRACT This study was conducted to evaluate the effects of dietary metabolisable energy (ME: 3.25, 3.40, 3.55, or 3.70 Mcal kg−1 and weaning weight (WW: light 4.0±0.7 kg, and heavy: 6.3±0.6 kg on productive response and energy utilization of weaned piglets. Sixty-four male piglets were housed in 32 metabolic cages (two animals per cage during the first 14 d postweaning. At day 15, only one animal per cage was kept until day 28. Body composition, energy, and nutrient deposition rates and energy utilization efficiency were measured through a comparative slaughter procedure. Piglets with light WW had a poorer feed conversion ratio and lower weight gain and feed intake when expressed per live weight. Increased ME led to greater daily fat deposition in the empty bodies (defined as weighted mean of the carcass + organs + blood, no intestinal content, while light WW piglets had a reduced protein deposition. Light WW piglets increased heat production with increased ME, but no effect was seen for the heavy WW piglets. By contrast, heavy WW piglets increased empty body gross energy as ME increased, while no influence was observed on light WW piglets. Increasing dietary energy levels did not contribute to the subsequent growth performance of piglets that were lighter at weaning. The lack of interaction between weaning weight and dietary ME content on growth performance does not support the hypothesis that light piglets at weaning do not exhibit compensatory growth because of limitations in energy intake.

Monitoring light source for CMS lead tungstate crystal calorimeter at LHC

CERN Document Server

Zhang Liang Ying; Zhu, R Y; Liu, D T

2001-01-01

Light monitoring will serve as an intercalibration for Compact Muon Solenoid (CMS) lead tungstate crystals in situ at the Large Hadronic Collider, which is crucial for maintaining crystal calorimeter's subpercent constant term in the energy resolution. This paper presents the design of the CMS electromagnetic calorimeter monitoring light source and high-level distribution system. The correlations between variations of the light output and the transmittance for the CMS choice of yttrium-doped PbWO/sub 4/ crystals were investigated and were used to study monitoring linearity and sensitivity as a function of wavelength. The monitoring wavelength was determined so that a good linearity as well as adequate sensitivity can be achieved. The performance of a custom manufactured tunable laser system is presented. Issues related to monitoring precision are discussed. (12 refs).

Modelling of NO{sub x} emission factors from heavy and light-duty vehicles equipped with advanced aftertreatment systems

Energy Technology Data Exchange (ETDEWEB)

Oliveira, M.L.M., E-mail: monalisa@unifor.br [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Silva, C.M. [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Moreno-Tost, R. [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain); Farias, T.L. [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Jimenez-Lopez, Antonio [IDMEC - Institute of Mechanical Engineering, Instituto Superior Tecnico, Technical University of Lisbon, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain); Rodriguez-Castellon, E. [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Unidad Asociada al Instituto de Catalisis, CSIC, Universidad de Malaga, Campus de Teatinos, 29071 Malaga (Spain)

2011-08-15

Highlights: {yields} Alternative SCR materials. {yields} Catalysts used in heavy-duty vehicles are based on V{sub 2}O{sub 5}-WO{sub 3}-TiO{sub 2}. {yields}Zeolites containing transition metal ions as catalysts for urea SCR has increased. {yields} FeZSM5 catalyst can be a possible candidate as far as pollutants regulation is considered. {yields} Regarding N{sub 2}O emissions mordenite based SCR do not emit this pollutant. - Abstract: NO{sub x} emission standards are becoming stringiest over the world especially for heavy-duty vehicles. To comply with current and future regulations some vehicle manufacturers are adopting exhaust aftertreatment systems known as Selective Catalytic Reduction (SCR). The catalysts are based on Vanadium (Va) and the reductant agent based on ammonia. However, Va is listed on the California Proposition 65 List as potentially causing cancer and alternatives are being studied. This paper presents a model based on neural networks that integrated with a road vehicle simulator allows to estimate NO{sub x} emission factors for different powertrain configurations, along different driving conditions, and covering commercial, zeolite and mordenite alternatives as the base monolith for SCR. The research included the experimental study of copper based and iron based zeolites (ZSM5 and Cuban natural mordenite). The response of NO{sub x} conversion efficiency was monitored in a laboratory for varying space velocity, oxygen, sulfur, water, NO{sub x} and SO{sub 2} emulating the conditions of a Diesel engine exhaust along a trip. The experimental data was used for training neural networks and obtaining a mathematical correlation between the outputs and inputs of the SCR system. The developed correlation was integrated with ADVISOR road vehicle simulator to obtain NO{sub x} emission factors and to test each SCR system installed on light-duty and heavy-duty vehicles for standardized driving cycles and real measured driving cycles. Despite having lower NO

Infinite-order-sudden method for light--heavy--light reactions: Application to D+HCl→DCl+H

International Nuclear Information System (INIS)

Clary, D.C.; Drolshagen, G.

1982-01-01

An infinite-order-sudden (IOS) theory for light-heavy-light reactions is applied to the D+HCl(v = 0, j)→DCl(v'< or =1, j')+H reaction. The results are compared with those obtained using a more accurate quantum-dynamical technique, the ESA--CSA method, in which the energy sudden approximation is used for the entrance channel, while the centrifugal sudden approximation is employed for the exit channel. The computations have been performed using LEPS and DIM potential energy surfaces. We obtain good agreement between the IOS and ESA--CSA results, not only for averaged quantities such as rate coefficients, but also for detailed vibrational-rotational reactive cross sections

Scaling violation in the heavy quark fragmentation functian

International Nuclear Information System (INIS)

Avaliani, I.S.; Kartvelishvili, V.G.

1981-01-01

The scaling violation in the heavy quark fragmentation functions is analysed in the framework of the leading logarithmic approximation in QCD and it is shown, that the slaling violation effects are more essential for heavy quarks, than for light ones. These results indicate that the D-meson inclusive spectra measurement is a sensitive test for some standard assumptions [ru

Heavy irradiation effects in radiation-resistant optical fibers

Energy Technology Data Exchange (ETDEWEB)

Shikama, Tatsuo [Tohoku Univ., Oarai, Ibaraki (Japan). Oarai Branch, Inst. for Materials Research

1998-07-01

Development of a system for optical measurements in a nuclear reactor has been progressing to investigate dynamic changes in a material caused by heavy irradiation. In such system, transfer of optical signals to out-pile measuring systems is being attempted by the use of optical fibers. In this report, the characteristics of optical fibers in the heavy irradiation field were summarized. It has been known that amorphous silica might produce radiolysis and structural defects by the exposure to ionizing radiation. The effects of heavy irradiation on molten silica were extremely complicated. A large intensity of visible light absorption occurred from an early time during start-up of the reactor. The absorption range was limited below 700 nm for the radiation associating fast neutron and the absorption was mostly attributed to non-bridging oxygen hole center. The depletion of optical transferring capacity under the radiation might be related to the internal stress. Therefore, it seems desirable to use optical fibers in the conditions without leading too much stress. (M.N.)

Insertion of lead lithium eutectic mixture in RELAP/SCDAPSIM Mod 4.0 for Fusion Reactor Systems

International Nuclear Information System (INIS)

Tiwari, Ashutosh; Allison, Brian; Hohorst, J.K.; Wagner, R.J.; Allison, Chris

2012-01-01

Highlights: ► Thermodynamic and transport properties of lead lithium eutectic mixture have been inserted in RELAP/SCDAPSIM MOD 4.0 code. ► Code results are verified for a simple pipe problem with lead lithium eutectic mixture flowing in it. ► Code is calculating the inserted properties of lead lithium eutectic mixture to a fairly good agreement. - Abstract: RELAP/SCDAPSIM Mod 4.0 code was developed by Innovative System Software (ISS) for the analysis of nuclear power plants (NPPs) cooled by light water and heavy water. Later on the code was expanded to analyze the NPPs cooled by liquid metal, in this sequence: lead bismuth eutectic mixture, liquid sodium and lead lithium eutectic mixture (LLE) are inserted in the code. This paper focuses on the insertion of liquid LLE as a coolant for NPPs in the RELAP/SCDAPSIM Mod 4.0 code. Evaluation of the code was made for a simple pipe problem connected with heat structures having liquid LLE as a coolant in it. The code is predicting well all the thermodynamic and transport properties of LLE.

Orbiting in collisions between light heavy ions (A/sub T/ + A/sub P/ < 50)

International Nuclear Information System (INIS)

Shapira, D.; Erb, K.A.; Ford, J.L.C. Jr.

1983-01-01

Evidence is presented for the formation of a long-lived rotating dinuclear complex in the early stages of the collision between light heavy nuclei. A study of the variation of the total kinetic energy of the outgoing fragments with bombarding energy allows a determination of the average dinuclear separation prior to scission. At higher bombarding energies the study reveals that the system of the two colliding nuclei has reached a critical value of angular momentum beyond which it can not be trapped into an orbiting configuration

Study of the light and heavy water leaks in nuclear reactors and development of techniques for their detection, location and estimation

International Nuclear Information System (INIS)

Bashiruddin Mahmood, S.

1979-01-01

In heavy water type nuclear reactors the detection and control of heavy water and light water escapes from different systems is of vital importance in the successful and economic operation of these type of plants. The high cost of heavy water makes it imperative to minimise all such escapes, in order to reduce the loss as well as the upgrading cost of downgraded collection recovered from the reactor building. Original methods and devices have been developed at the Karachi Nuclear Power Plant which successfully solve this problem. This report describes the constructional and operational features of these devices

Lead accumulation in the roadside soils from heavy density motor ...

African Journals Online (AJOL)

The levels of lead pollution in the roadside soils of the heavy density motor ways of Eastern Ethiopia, in particular; Modjo, Bishoftu and Adama towns were studied. Soil samples were collected from a total of 22 sampling sites while the control samples were obtained from places about 1 km away from the main roads of each ...

High resolution conductometry for isotopic assay of deuterium in mixtures of heavy water and light water

International Nuclear Information System (INIS)

Ananthanarayanan, R.; Sahoo, P.; Murali, N.

2014-01-01

A PC based high resolution conductivity monitoring technique has been deployed for determination of isotopic purity of heavy water in samples containing heavy water and light water mixtures using pulsating sensor based conductivity monitoring instrument. The technique involves accurate determination of conductivities of a series of specially treated heavy water and light water mixtures of various compositions at a constant solution temperature. The shift in conductivity (Δκ), which is the difference between conductivities of composite mixture after and before the formation of a typical complex compound (boric acid–mannitol complex in this case), shows a smooth and reproducible decreasing trend with increase in percentage composition of heavy water. This relation, which is obtained by appropriate calibration, is used in the software program for direct display of isotopic purity of heavy water. The technique is examined for determination of percentage composition of heavy water in the entire range of concentration (0-100 %) with reasonable precision (relative standard deviation, RSD ≤1.5 %). About 1 mL of sample is required for each analysis and analysis is completed within a couple of minutes after pretreatment of sample. The accuracy in measurement is ≤1.75 %. (author)

Application of heavy-light methods to B meson physics

International Nuclear Information System (INIS)

Eichten, E.; Hockney, G.; Thacker, H.B.

1989-01-01

The heavy-light method is applied to the study of the B meson spectrum, the pseudoscalar decay constant f B , the mixing (B) parameter, and exclusive semileptonic B meson decays. Preliminary results are discussed for f B and the B parameter at β = 5.7 and κ = 0.165 on a 12 3 x 24 lattice and at β = 5.9 and κ = 0.158 on a 16 3 x 32 lattice. 9 refs., 2 figs., 2 tabs

Heavy quark effective theory and heavy baryon transitions

International Nuclear Information System (INIS)

Hussain, F.

1992-01-01

The heavy quark effective theory (HQET) is applied to study the weak decay of heavy mesons and heavy baryons and to predict the form factors for heavy to heavy and heavy to light transitions. 28 refs, 10 figs, 2 tabs

Heavy baryons in the heavy quark effective theory

International Nuclear Information System (INIS)

Koerner, J.G.; Thompson, G.

1991-10-01

We give a mini-review of recent results on current-induced transitions between heavy baryons (and between heavy and light baryons) in the light of the new spin and flavour symmetries of the Heavy Quark Effective Theory (HQET). We discuss the structure of the 1/m corrections to the heavy mass limit and outline a diagrammatic proof that there are no 0(1/m) correction to the Voloshin-Shifman normalization condition at zero recoil. (orig.)

Heavy-quark fragmentation functions at next-to-leading perturbative QCD

Energy Technology Data Exchange (ETDEWEB)

Moosavi Nejad, S.M. [Yazd University, Faculty of Physics, Yazd (Iran, Islamic Republic of); Institute for Research in Fundamental Sciences (IPM), School of Particles and Accelerators, Tehran (Iran, Islamic Republic of); Sartipi Yarahmadi, P. [Yazd University, Faculty of Physics, Yazd (Iran, Islamic Republic of)

2016-10-15

It is well known that the dominant mechanism to produce hadronic bound states with large transverse momentum is fragmentation. This mechanism is described by the fragmentation functions (FFs) which are the universal and process-independent functions. Here, we review the perturbative FFs formalism as an appropriate tool for studying these hadronization processes and detail the extension of this formalism at next-to-leading order (NLO). Using Suzuki's model, we calculate the perturbative QCD FF for a heavy quark to fragment into a S-wave heavy meson at NLO. As an example, we study the LO and NLO FFs for a charm quark to split into the S-wave D-meson and compare our analytic results both with experimental data and well-known phenomenological models. (orig.)

Fusion-Fission like studies from medium heavy to light compound systems

International Nuclear Information System (INIS)

Heusch, B.

1991-01-01

It has been shown that for systems as light as A CN = 47 up to systems just above the Businaro Gallone point in the mass region of 100 to 110 the probability for a system to deexcite by the fission channel, is not negligible. As predicted, the asymmetrical separation becomes dominant when the A CN mass is decreasing but the symmetrical mode remains measurable. The ambiguities in the measured outgoing fragment distributions arise from the competition with IMF emissions as well as dynamical fission processes which depend strongly on the studied system. Fully relaxed DIC has also be used to interpret the results. I tried to show that precise checks on the behavior of two neighbouring systems as well as search for entrance channel effect and/or energy dependence bring evidence enough that the deexcitation of the compound nucleus can account for the symmetric and asymmetric fission channels as well as IMF emissions. This is strongly supported by different recent calculations all done in this frame. These all conclusions indicate also that the RLDM fails in the data interpretation. The strength of the fission channel depends strongly on the possibilities a system has to deexcite. For very light systems especially the number of open channels available determines directly the flux repartition between direct or compound processes and therefore very large differences in the general behaviour of two neighbouring systems can be observed. 15 figs

Proceedings of the workshop on microscopic and phenomenological studies of the interactions between light-heavy ions

International Nuclear Information System (INIS)

Yamaguchi, S.

1993-01-01

The workshop 'Microscopic and Phenomenological Studies of the Interactions between Light-Heavy Ions' was held at Institute for Nuclear Study, University of Tokyo from Dec. 24 to Dec. 26, 1991. The workshop included 1) studies of the nucleus-nucleus interactions of the systems as 16 O- 16 O, 16 O- 15 N, etc., or the studies of the elastic and inelastic scatterings and the transfer reactions in such systems, 2) structure and reactions of neutron-rich nuclei, 3) microscopic derivation of the effective two-nucleon interactions, 4) development of the methods of techniques applied to the heavier systems. (author)

High-resolution velocity measurements on fully identified light nuclides produced in {sup 56}Fe + protons and {sup 56}Fe + titanium systems

Energy Technology Data Exchange (ETDEWEB)

Napolitani, P. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Institut de Physique Nucleaire (IPN), 91 - Orsay (France); Schmidt, K.H. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany); Botvina, A.S. [Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)]|[Rossijskaya Akademiya Nauk, Moscow (Russian Federation). Inst. Yadernykh Issledovanij; Rejmund, F.; Tassan-Got, L. [Institut de Physique Nucleaire (IPN), 91 - Orsay (France); Villagrasa, C. [CEA Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (FR). Dept. d' Astrophysique, de Physique des Particules, de Physique Nucleaire et de l' Instrumentation Associee (DAPNIA)

2004-07-01

New experimental results on the kinematics and the residue production are obtained for the interactions of {sup 56}Fe projectiles with protons and {sup nat}Ti target nuclei, respectively, at the incident energy of 1 A GeV. The titanium-induced reaction serves as a reference case for multifragmentation. Already in the proton-induced reaction, the characteristics of the isotopic cross sections and the shapes of the velocity spectra of light residues indicate that high thermal energy is deposited in the system during the collision. In the {sup 56}Fe+p system the high excitation seems to favour the onset of fast break-up decays dominated by very asymmetric partitions of the disassembling system. This configuration leads to the simultaneous formation of one or more light fragments together with one heavy residue. (orig.)

Pore network modelling of heavy oil depressurization : a parametric study of factors affecting critical gas saturation and three-phase relative permeabilities

Energy Technology Data Exchange (ETDEWEB)

Bondino, I.; McDougall, S.D. [Heriot-Watt Univ., Edinburgh, Scotland (United Kingdom); Hamon, G. [TotalFina Elf Exploration and Production (France)

2002-07-01

A review of how the bubble nucleation process affects the efficiency of heavy oil recovery was presented along with a discussion regarding a pore-scale simulator technique to depressurize heavy oil systems. A light oil depressurization simulation is also presented in which a straightforward instantaneous nucleation (IN) model and a more intricate progressive nucleation (PN) model have been used. Simulation results are compared to those derived from the heavy oil systems. The nucleation of bubbles, their growth by solute diffusion and expansion, plus the final stages of coalescence migration and production are the main steps in the depressurization process which were accounted for in a 3-phase simulator. The model can also determine the impact of bubble density and gas-oil diffusion coefficient on critical gas saturation and 3-phase relative permeability. The difference in results for light and heavy oils was also highlighted. In the first scenario, the evolution of gas was characterized by embryonic bubbles that are quickly and randomly nucleated once bubble-point pressure is reached. A stochastic algorithm was developed for PN from experimental observations. IN and PN observations were not necessarily contradictory. It was determined that the high interfacial tension of heavy oils leads to a more compact, capillary-dominated pattern of gas evolution compared to light oils, resulting in improved recoveries for heavy oil systems. 23 refs., 6 tabs., 23 figs.

Personalized Risk Assessment in Never, Light, and Heavy Smokers in a prospective cohort in Taiwan.

Science.gov (United States)

Wu, Xifeng; Wen, Chi Pang; Ye, Yuanqing; Tsai, MinKwang; Wen, Christopher; Roth, Jack A; Pu, Xia; Chow, Wong-Ho; Huff, Chad; Cunningham, Sonia; Huang, Maosheng; Wu, Shuanbei; Tsao, Chwen Keng; Gu, Jian; Lippman, Scott M

2016-11-02

The objective of this study was to develop markedly improved risk prediction models for lung cancer using a prospective cohort of 395,875 participants in Taiwan. Discriminatory accuracy was measured by generation of receiver operator curves and estimation of area under the curve (AUC). In multivariate Cox regression analysis, age, gender, smoking pack-years, family history of lung cancer, personal cancer history, BMI, lung function test, and serum biomarkers such as carcinoembryonic antigen (CEA), bilirubin, alpha fetoprotein (AFP), and c-reactive protein (CRP) were identified and included in an integrative risk prediction model. The AUC in overall population was 0.851 (95% CI = 0.840-0.862), with never smokers 0.806 (95% CI = 0.790-0.819), light smokers 0.847 (95% CI = 0.824-0.871), and heavy smokers 0.732 (95% CI = 0.708-0.752). By integrating risk factors such as family history of lung cancer, CEA and AFP for light smokers, and lung function test (Maximum Mid-Expiratory Flow, MMEF 25-75% ), AFP and CEA for never smokers, light and never smokers with cancer risks as high as those within heavy smokers could be identified. The risk model for heavy smokers can allow us to stratify heavy smokers into subgroups with distinct risks, which, if applied to low-dose computed tomography (LDCT) screening, may greatly reduce false positives.

Inclusive Decays of Heavy Quarkonium to Light Particles

CERN Document Server

Brambilla, Nora; Pineda-Ruiz, A; Soto, J; Vairo, Antonio; Brambilla, Nora; Eiras, Dolors; Pineda, Antonio; Soto, Joan; Vairo, Antonio

2003-01-01

We derive the imaginary part of the potential NRQCD Hamiltonian up to order 1/m^4, when the typical momentum transfer between the heavy quarks is of the order of Lambda_{QCD} or greater, and the binding energy E much smaller than Lambda_{QCD}. We use this result to calculate the inclusive decay widths into light hadrons, photons and lepton pairs, up to O(mv^3 x (Lambda_{QCD}^2/m^2,E/m)) and O(mv^5) times a short-distance coefficient, for S- and P-wave heavy quarkonium states, respectively. We achieve a large reduction in the number of unknown non-perturbative parameters and, therefore, we obtain new model-independent QCD predictions. All the NRQCD matrix elements relevant to that order are expressed in terms of the wave functions at the origin and six universal non-perturbative parameters. The wave-function dependence factorizes and drops out in the ratio of hadronic and electromagnetic decay widths. The universal non-perturbative parameters are expressed in terms of gluonic field-strength correlators, which ...

Study on lead transportation in air-water-paddy system with 210Pb as tracer

International Nuclear Information System (INIS)

Li Shuding; Zhang Hairong; Ma Xuejun

1987-08-01

With 210 PbCl 2 as tracer, a research into lead sources in brown rice, lead distribution in soil and rice, lead chemical forms in soil and their change with time, availability of soil for rice and effect of soil pH on the Pb adsorption was carried out in air-water-paddy system near cities and towns located upper and middle reaches of Liaohe River, northeastern China. Test soil was light acid meadow brown soil. The Pb proportions in rice grain derived from the soil, airborne dust and irrigation water and the transportation pathway to brown rice were investigated. Transportation coefficients of Pb in the system were determined by tracer experiment. It was indicated that the Pb concentration in rice root, the Pb concentration and its distribution in the soil are main factors effecting Pb transportation to rice. Based on the simulation test, mathematical model for computing soil environmental capacity of Pb in the system is put forward. The soil environmental capacity of Pb computed is 1600 - 1700 ppm, i.e. 3.6 - 3.8 t/ha. The computed result was in agreement with the observed. The mathematical model was also used to compute soil enviromental capacity of those heavy metal corresponding respectively with 203 Hg, 115+115m Cd, 65 Zn, 51 Cr, 65 Ni, 60 Co etc

Systematic model calculations of the hyperfine structure in light and heavy ions

CERN Document Server

Tomaselli, M; Nörtershäuser, W; Ewald, G; Sánchez, R; Fritzsche, S; Karshenboim, S G

2003-01-01

Systematic model calculations are performed for the magnetization distributions and the hyperfine structure (HFS) of light and heavy ions with a mass close to A ~ 6 208 235 to test the interplay of nuclear and atomic structure. A high-precision measurement of lithium-isotope shifts (IS) for suitable transition, combined with an accurate theoretical evaluation of the mass-shift contribution in the respective transition, can be used to determine the root-mean-square (rms) nuclear-charge radius of Li isotopes, particularly of the halo nucleus /sup 11/Li. An experiment of this type is currently underway at GSI in Darmstadt and ISOLDE at CERN. However, the field-shift contributions between the different isotopes can be evaluated using the results obtained for the charge radii, thus casting, with knowledge of the ratio of the HFS constants to the magnetic moments, new light on the IS theory. For heavy charged ions the calculated n- body magnetization distributions reproduce the HFS of hydrogen-like ions well if QED...

Molecular dynamics simulations of ion range profiles for heavy ions in light targets

Energy Technology Data Exchange (ETDEWEB)

Lan, C. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Xue, J.M. [State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Zhang, Y., E-mail: Zhangy1@ornl.gov [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Morris, J.R. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States); Zhu, Z. [Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Gao, Y.; Wang, Y.G.; Yan, S. [State Key Laboratory of Nuclear Physics and Technology, Peking University, 100871 (China); Weber, W.J. [Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

2012-09-01

The determination of stopping powers for slow heavy ions in targets containing light elements is important to accurately describe ion-solid interactions, evaluate ion irradiation effects and predict ion ranges for device fabrication and nuclear applications. Recently, discrepancies of up to 40% between the experimental results and SRIM (Stopping and Range of Ions in Matter) predictions of ion ranges for heavy ions with medium and low energies (<{approx}25 keV/nucleon) in light elemental targets have been reported. The longer experimental ion ranges indicate that the stopping powers used in the SRIM code are overestimated. Here, a molecular dynamics simulation scheme is developed to calculate the ion ranges of heavy ions in light elemental targets. Electronic stopping powers generated from both a reciprocity approach and the SRIM code are used to investigate the influence of electronic stopping on ion range profiles. The ion range profiles for Au and Pb ions in SiC and Er ions in Si, with energies between 20 and 5250 keV, are simulated. The simulation results show that the depth profiles of implanted ions are deeper and in better agreement with the experiments when using the electronic stopping power values derived from the reciprocity approach. These results indicate that the origin of the discrepancy in ion ranges between experimental results and SRIM predictions in the low energy region may be an overestimation of the electronic stopping powers used in SRIM.

Tritium isotope separation from light and heavy water by bipolar electrolysis

International Nuclear Information System (INIS)

Petek, M.; Ramey, D.W.; Taylor, R.D.; Kobisk, E.H.

1980-01-01

A process for separating tritium from light and heavy water is described. Hydrogen is transferred at and through bipolar electrodes at rates H > D > T. In a cell containing several bipolar electrodes placed in series between two terminal electrodes, a flow of hydrogen is established from the terminal anode compartment toward the terminal cathode. An electrolyte feed containing tritium is continuously added to the system and is subsequently transported countercurrent to the hydrogen mass transfer. A cascaded system is established, in which effluent streams enriched and depleted in tritium can be withdrawn. The voltage drop is smaller at any bipolar electrode as compared to the voltage for normal electrolysis. Cell design is compact because isotope separation occurs at bipolar electrodes without evolution of gas. Isotope separation was demonstrated in laboratory cells where a steady-state tritium concentration gradient was attained. This gradient was in agreement with concentrations calculated from a derived mathematical model

B-meson decay constants from 2+1-flavor lattice QCD with domain-wall light quarks and relativistic heavy quarks

Energy Technology Data Exchange (ETDEWEB)

Christ, Norman H. [Columbia Univ., New York, NY (United States); Flynn, Jonathan M. [Univ. of Southampton, Southampton (United Kingdom); Izubuchi, Taku [Brookhaven National Lab. (BNL), Upton, NY (United States); Kawanai, Taichi [RIKEN, Wako (Japan); Brookhaven National Lab. (BNL), Upton, NY (United States); Lehner, Christoph [Brookhaven National Lab. (BNL), Upton, NY (United States); Soni, Amarjit [Brookhaven National Lab. (BNL), Upton, NY (United States); Van de Water, Ruth S. [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Witzel, Oliver [Boston Univ., Boston, MA (United States)

2015-03-10

We calculate the B-meson decay constants f_B, f_Bs, and their ratio in unquenched lattice QCD using domain-wall light quarks and relativistic b-quarks. We use gauge-field ensembles generated by the RBC and UKQCD collaborations using the domain-wall fermion action and Iwasaki gauge action with three flavors of light dynamical quarks. We analyze data at two lattice spacings of a ≈ 0.11, 0.086 fm with unitary pion masses as light as M_π ≈ 290 MeV; this enables us to control the extrapolation to the physical light-quark masses and continuum. For the b-quarks we use the anisotropic clover action with the relativistic heavy-quark interpretation, such that discretization errors from the heavy-quark action are of the same size as from the light-quark sector. We renormalize the lattice heavy-light axial-vector current using a mostly nonperturbative method in which we compute the bulk of the matching factor nonperturbatively, with a small correction, that is close to unity, in lattice perturbation theory. We also improve the lattice heavy-light current through O(α_sa). We extrapolate our results to the physical light-quark masses and continuum using SU(2) heavy-meson chiral perturbation theory, and provide a complete systematic error budget. We obtain f_B⁰ = 196.2(15.7) MeV, f_B⁺ = 195.4(15.8) MeV, f_Bs = 235.4(12.2) MeV, f_Bs/f_B⁰ = 1.193(59), and f_Bs/f_B⁺ = 1.220(82), where the errors are statistical and total systematic added in quadrature. In addition, these results are in good agreement with other published results and provide an important independent cross check of other three-flavor determinations of B-meson decay constants using staggered light quarks.

Long-distance behavior of the quark-antiquark static potential. Application to light-quark mesons and heavy quarkonia

International Nuclear Information System (INIS)

Gonzalez, P.

2009-01-01

Screening effects from sea pairs on the quark-antiquark static potential are analyzed phenomenologically from the light-quark to the heavy-quark meson spectra. From the high excited light-quark meson spectrum, a universal form for the screened static potential is proposed. This potential is then successfully applied to heavy quarkonia. Our results suggest the assignment of X(4260) to the 4s state of charmonium and the possible existence of a 5s bottomonium resonance around 10748 MeV.

HQE parameters from unquenched lattice data on pseudoscalar and vector heavy-light meson masses

Science.gov (United States)

Gambino, Paolo; Melis, Aurora; Simula, Silvano

2018-03-01

We present a new lattice determination of some of the parameters appearing both in the Operator Product Expansion (OPE) analysis of the inclusive semileptonic B-meson decays and in the Heavy Quark Expansion (HQE) of the pseudoscalar (PS) and vector (V) heavy-light meson masses. We perform a lattice QCD (LQCD) computation of PS and V heavy-light meson masses for heavy-quark masses mh in the range from mcphys to ≃ 4mbphys. We employed the Nf = 2 + 1 + 1 gauge configurations of the European Twisted Mass Collaboration (ETMC) at three values of the lattice spacing a ≃ (0.062,0.082,0.089) fm with pion masses in the range Mπ ≃ (210 - 450) MeV. The heavy-quark mass is simulated directly on the lattice up to ≃ 3mcphys. The interpolation to the physical mbphys is performed using the ETMC ratio method and adopting the kinetic mass scheme. We obtain mbkin (1 GeV) = 4.61(20) GeV (m̅b(m̅b) = 4.26(18) GeV in the MS scheme). The lattice data are analyzed in terms of the HQE and the matrix elements of dimension-4 and dimension-5 operators are extracted with good precision, namely: Λ¯ = 0.552(26) GeV, μπ2 = 0.321(32) GeV2 and μG2(mb) = 0.253(25)GeV2. The data also allow for an estimate of the dimension-6 operator matrix elements.

Heavy metal dynamics in the soil-leaf-fruit system under intensive apple cultivation

Directory of Open Access Journals (Sweden)

Murtić Senad

2014-01-01

Full Text Available One of the major problems confronting agricultural production is heavy metal contamination of agricultural soils, which imposes considerable limitations on productivity and leads to great consumer health and safety concerns about the products obtained on these soils. The objective of this study was to evaluate heavy metal dynamics in the soil-leaf-fruit system in an intensive apple cv. 'Idared' planting located in the Municipality of Goražde. Heavy metal contents in the soil samples and plant material were determined by atomic absorption spectrophotometry using a Shimadzu 7000 AA device, according to the instructions specified in the ISO 11047 method. The dynamics of the heavy metals analyzed, excepting zinc, in the soil-leaf-fruit system was characterized by relatively high total levels of heavy metals in the soil and a very low degree of their accumulation in the leaves and in particular the fruits. No fruit sample was found to have toxic levels of any of the heavy metals analyzed. In terms of soil contamination, this suggests the suitability of the study location for safe apple fruit production.

1. contribution of the dynamics on the reactions mechanisms in the heavy ions collisions at the intermediary energies (20-100 MeV/A) for the light systems. 2. management of radioactive wastes by new options: nuclear data measurement programme between 20 and 150 MeV

International Nuclear Information System (INIS)

Eudes, Ph.

2000-01-01

The first part concerns the features of emitted charged particles in heavy ions reactions that have been studied in the framework of the semi classical Landau-Vlasov approach for the light system Ar + Al at 65 MeV/nucleon incident energy. The second part is devoted to the radioactive waste management (transmutation), but it was necessary to increase the data banks evaluated in neutrons up to 150-200 MeV and to create a data bank in protons. In the European framework it was decide to focus on three representative elements: lead (spallation target), iron (structure material) and uranium (actinide). (N.C.)

Neutron disadvantage factors in heavy water and light water reactors

International Nuclear Information System (INIS)

Pop-Jordanov, J.

1966-01-01

A number od heavy water and light water reactor cells are analyzed in this paper by applying analytical methods of neutron thermalization. Calculations done according to the one-group Amouyal-Benoist method are included in addition. Computer codes for ZUSE Z-23 computer were written by applying both methods. The obtained results of disadvantage factors are then compared to results obtained by one-group P 3 approximation and by multigroup K7-THERMOS code [sr

Light vs. heavy sedation during mechanical ventilation after oesophagectomy--a pilot experimental study focusing on memory.

Science.gov (United States)

Samuelson, K A M; Lundberg, D; Fridlund, B

2008-09-01

To assess and compare the feasibility and stressful memories of light vs. heavy sedation during post-operative mechanical ventilation. Randomized clinical trial in one general intensive care unit (ICU) in a Swedish university hospital. Thirty-six adults were randomly assigned to receive either light [Motor Activity Assessment Scale (MAAS) 3-4] or heavy (MAAS 1-2) sedation with continuous i.v. infusion of propofol during post-operative invasive mechanical ventilation after oesophagectomy. The patients were interviewed at the general ward 5 days post-ICU using the ICU Memory Tool and the ICU Stressful Experience Questionnaire, and 2 months post-ICU using the Impact of Event Scale Revised. Patient data and hourly recorded MAAS values were collected after the interviews. Seventy-four per cent of the 139 MAAS values in the light sedation group (n=18) and 79% of the 142 in the heavy sedation group (n=18) were within the targeted levels, and the median MAAS scores were 3.0 vs. 1.25, respectively. Intention-to-treat analyses showed no significant difference in the prevalence of stressful memories between groups, including endotracheal tube discomfort, presenting wide 95% confidence intervals for the difference in outcome estimates. Excluding the patients with a prolonged ICU stay (n=3), a higher prevalence of delusional memories was found in the heavy sedation group (31% vs. 0%, P=0.04). This small randomized-controlled pilot study suggests that a light sedation regimen during short-term post-operative mechanical ventilation after major surgery is feasible without increasing patient discomfort.

Light-induced defects in hybrid lead halide perovskite

Science.gov (United States)

Sharia, Onise; Schneider, William

One of the main challenges facing organohalide perovskites for solar application is stability. Solar cells must last decades to be economically viable alternatives to traditional energy sources. While some causes of instability can be avoided through engineering, light-induced defects can be fundamentally limiting factor for practical application of the material. Light creates large numbers of electron and hole pairs that can contribute to degradation processes. Using ab initio theoretical methods, we systematically explore first steps of light induced defect formation in methyl ammonium lead iodide, MAPbI3. In particular, we study charged and neutral Frenkel pair formation involving Pb and I atoms. We find that most of the defects, except negatively charged Pb Frenkel pairs, are reversible, and thus most do not lead to degradation. Negative Pb defects create a mid-gap state and localize the conduction band electron. A minimum energy path study shows that, once the first defect is created, Pb atoms migrate relatively fast. The defects have two detrimental effects on the material. First, they create charge traps below the conduction band. Second, they can lead to degradation of the material by forming Pb clusters.

Lead and other heavy metals in stream sediments in the area of Meža valley

Directory of Open Access Journals (Sweden)

Julija Fux

2007-12-01

Full Text Available In the Meža valley, lead – zinc ore has been exploited and processed for more than 300 years, which has strongly influenced the environment.Previous investigation shave shown increased concentrations of lead and some other metals. At the end of the 20th century, the Meža River was considered a stream with the highest concentrations of heavy metals in Slovenia.When the mine and processing plants ceased to operate, the direct transfer of heavy metals into the environment has strongly decreased. However, the deposits of poor ore and wastes from ore processing have remained as an indirect source of heavy metal pollution. From those places heavy metals have been washed out into the nearby streams, and carried into the Meža River and further into the Drava River. Chemical analysis of the Meža River and its tributaries has shown heavy pollution of the upper Meža River sediments with lead, zinc, molybdenum and cadmium, and partly with arsenic. In the lower Meža valley, those concentrations are mildly decreased. Concentrations of cobalt, chrome, copper and nickel are increased in the area around Ravne as a result of the ironworks industry. Mušenik and Jančarjev potok, both tributaries of the Meža River, contribute a high portion of heavy metal load to the Meža River. A specific case is Helenski potok,in which the concentrations of heavy metals strongly surpass the concentrations measured at all other locations. Although more than 10 years have passed since the mine and ore processing plant in the upper Meža valley were closed, the production has ceased and the rehabilitation measures have been taken, the environment in the upper Meža valley is still highly polluted.

Isotope effect in heavy/light water suspensions of optically active gold nanoparticles

Science.gov (United States)

Kutsenko, V. Y.; Artykulnyi, O. P.; Petrenko, V. I.; Avdeev, M. V.; Marchenko, O. A.; Bulavin, L. A.; Snegir, S. V.

2018-04-01

Aqueous suspensions of optically active gold nanoparticles coated with trisodium citrate were synthesized in light (H2O) water and mixture of light and heavy (H2O/D2O) water using the modified Turkevich protocol. The objective of the paper was to verify sensitivity of neutron scattering methods (in particular, neutron reflectometry) to the potential isotope H/D substitution in the stabilizing organic shell around particles in colloidal solutions. First, the isotope effect was studied with respect to the changes in the structural properties of metal particles (size, shape, crystalline morphology) in solutions by electron microscopy including high-resolution transmission electron microscopy from dried systems. The structural factors determining the variation in the adsorption spectra in addition to the change in the optical properties of surrounding medium were discussed. Then, neutron reflectometry was applied to the layered nanoparticles anchored on a silicon wafer via 3-aminopropyltriethoxysilane molecules to reveal the presence of deuterated water molecules in the shell presumably formed by citrate molecules around the metallic core.

Lighting system with a device for reducing system wattage

NARCIS (Netherlands)

1996-01-01

A lighting system having a high pressure gas discharge lamp intended to be operated on a stabilization ballast further includes a low loss device to reduce the current through the ballast and lamp, thereby reducing system wattage for energy savings. For a lead-type ballast, the current reducing

Matrix light and pixel light: optical system architecture and requirements to the light source

Science.gov (United States)

Spinger, Benno; Timinger, Andreas L.

2015-09-01

Modern Automotive headlamps enable improved functionality for more driving comfort and safety. Matrix or Pixel light headlamps are not restricted to either pure low beam functionality or pure high beam. Light in direction of oncoming traffic is selectively switched of, potential hazard can be marked via an isolated beam and the illumination on the road can even follow a bend. The optical architectures that enable these advanced functionalities are diverse. Electromechanical shutters and lens units moved by electric motors were the first ways to realize these systems. Switching multiple LED light sources is a more elegant and mechanically robust solution. While many basic functionalities can already be realized with a limited number of LEDs, an increasing number of pixels will lead to more driving comfort and better visibility. The required optical system needs not only to generate a desired beam distribution with a high angular dynamic, but also needs to guarantee minimal stray light and cross talk between the different pixels. The direct projection of the LED array via a lens is a simple but not very efficient optical system. We discuss different optical elements for pre-collimating the light with minimal cross talk and improved contrast between neighboring pixels. Depending on the selected optical system, we derive the basic light source requirements: luminance, surface area, contrast, flux and color homogeneity.

Comparisons of system benefits and thermo-economics for exhaust energy recovery applied on a heavy-duty diesel engine and a light-duty vehicle gasoline engine

International Nuclear Information System (INIS)

Wang, Tianyou; Zhang, Yajun; Zhang, Jie; Peng, Zhijun; Shu, Gequn

2014-01-01

Highlights: • Comparisons of exhaust energy recovery are launched between two types of engine. • System performances are analyzed in terms of benefits and thermo-economics. • Diesel engine system presents superior to gasoline type in economic applicability. • Only diesel engine system using water under full load meets the economic demand. - Abstract: Exhaust energy recovery system (EERS) based on Rankine cycle (RC) in internal combustion engines have been studied mainly on heavy-duty diesel engines (D) and light-duty vehicle gasoline engines (G), however, little information available on systematical comparisons and evaluations between the two applications, which is a particularly necessary summary for clarifying the differences. In this paper, the two particular systems are compared quantitatively using water, R141b, R123 and R245fa as working fluids. The influences of evaporating pressure, engine type and load on the system performances are analyzed with multi-objectives, including the thermal efficiency improvement, the reduced CO 2 emission, the total heat transfer area per net power output (APP), the electricity production cost (EPC) and the payback period (PBP). The results reveal that higher pressure and engine load would be attractive for better performances. R141b shows the best performances in system benefits for the D-EERS, while water exhibits the largest contributions in the G-EERS. Besides, water performs the best thermo-economics, and R245fa serves as the most uneconomical fluid. The D-EERS presents superior to the G-EERS in the economic applicability as well as much more CO 2 emission reductions, although with slightly lower thermal efficiency improvement, and only the D-EERS with water under the full load meets the economic demand. Therefore the EERS based on RC serve more applicable on the heavy-duty diesel engine, while it might be feasible for the light-duty vehicle gasoline engine as the state-of-the art technologies are developed in the

40 CFR Appendix X to Part 86 - Sampling Plans for Selective Enforcement Auditing of Heavy-Duty Engines and Light-Duty Trucks

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Sampling Plans for Selective Enforcement Auditing of Heavy-Duty Engines and Light-Duty Trucks X Appendix X to Part 86 Protection of... Plans for Selective Enforcement Auditing of Heavy-Duty Engines and Light-Duty Trucks Table 1—Sampling...

Model based control for waste heat recovery rankine cycle system in heavy duty trucks

OpenAIRE

Grelet, Vincent; Dufour, Pascal; Nadri, Madiha; Lemort, Vincent; Reiche, Thomas

2015-01-01

Driven by future emissions legislations and increase in fuel prices engine, gas heat recovering has recently attracted a lot of interest. In the past few years, a high number of studies have shown the interest of energy recovery Rankine based systems for heavy duty trucks engine compounding. Recent studies have brought a significant potential for such a system in a Heavy Duty (HD) vehicle, which can lead to a decrease in fuel consumption of about 5% [Wang et al. (2011)] and reduce engine emis...

Heavy baryon transitions and the heavy quark effective theory

International Nuclear Information System (INIS)

Hussain, F.

1992-01-01

Heavy baryon decays are studied in the context of the Bethe-Salpeter approach to the heavy quark effective theory. A drastic reduction, in the number of independent form factors, is found. Results are presented both for heavy to heavy and heavy to light baryon decays. (orig.)

Comparison of potential models through heavy quark effective theory

International Nuclear Information System (INIS)

Amundson, J.F.

1995-01-01

I calculate heavy-light decay constants in a nonrelativistic potential model. The resulting estimate of heavy quark symmetry breaking conflicts with similar estimates from lattice QCD. I show that a semirelativistic potential model eliminates the conflict. Using the results of heavy quark effective theory allows me to identify and compensate for shortcomings in the model calculations in addition to isolating the source of the differences in the two models. The results lead to a rule as to where the nonrelativistic quark model gives misleading predictions

Decay heat removal analyses on the heavy liquid metal cooled fast breeding reactor. Comparisons of the decay heat removal characteristics on lead, lead-bismuth and sodium cooled reactors

International Nuclear Information System (INIS)

Sakai, Takaaki; Ohshima, Hiroyuki; Yamaguchi, Akira

2000-04-01

The feasibility study on several concepts for the commercial fast breeder reactor(FBR) in future has been conducted in JNC for the kinds of possible coolants and fuel types to confirm the direction of the FBR developments in Japan. In this report, Lead and Lead-Bismuth eutectic coolants were estimated for the decay heat removal characteristics by the comparison with sodium coolant that has excellent features for the heat transfer and heat transport performance. Heavy liquid metal coolants, such as Lead and Lead-Bismuth, have desirable chemical inertness for water and atmosphere. Therefore, there are many economical plant proposals without an intermediate heat transport system that prevents the direct effect on a reactor core by the chemical reaction between water and the liquid metal coolant at the hypocritical tube failure accidents in a steam generator. In this study, transient analyses on the thermal-hydraulics have been performed for the decay heat removal events in Equivalent plant' with the Lead, Lead-Bismuth and Sodium coolant by using Super-COPD code. And a resulted optimized lead cooled plant in feasibility study was also analyzed for the comparison. In conclusion, it is become clear that the natural circulation performance, that has an important roll in passive safety characteristic of the reactor, is more excellent in heavy liquid metals than sodium coolant during the decay heat removal transients. However, we need to confirm the heat transfer reduction by the oxidized film or the corrosion products expected to appear on the heat transfer surface in the Lead and Lead-Bismuth circumstance. (author)

Lead/tin resonator development at the Stony Brook heavy-ion linac

International Nuclear Information System (INIS)

Sikora, J.; Ben-Zvi, I.; Brennan, J.M.; Cole, M.; Noe, J.W.

1988-01-01

The Stony Brook Nuclear Structure Laboratory (NSL) has operated a superconducting heavy-ion booster linac since April 1983. The 40 copper split-loop resonators were developed and fabricated at Cal-Tech and plated with lead at Stony Brook. These original lead surfaces have given stable performance for the last 4 years, at an average accelerating gradient of about 2.5 MV/m in the high-β section. The low-β resonators however have never run reliably on-line much better than 2.0 MV/m, due to excessive vibration of their rather soft loop arms in the working accelerator environment. For the last 2-3 years the efforts of the Stony Brook accelerator development group have been focused on (1) a retrofit of the low-beta section of the linac with new QWRs and (2) the further development of plated superconducting surfaces. In particular a Sn/Pb alloy has been shown to give resonator performance at least comparable to that obtained with pure Pb but with a greatly simplified plating technique, as discussed below. Recently a possible heavy-ion injector based on superconducting RF quadrupole (RFQ) structures has also been studied. 13 references, 3 figures, 1 table

Sudakov resummation for subleading SCET currents and heavy-to-light form factors

International Nuclear Information System (INIS)

Hill, Richard J.; Becher, Thomas; Lee, Seung J.; Neubert, Matthias

2004-01-01

The hard-scattering contributions to heavy-to-light form factors at large recoil are studied systematically in soft-collinear effective theory (SCET). Large logarithms arising from multiple energy scales are re-summed by matching QCD onto SCET in two stages via an intermediate effective theory. Anomalous dimensions in the intermediate theory are computed, and their form is shown to be constrained by conformal symmetry. Renormalization-group evolution equations are solved to give a complete leading-order analysis of the hard-scattering contributions, in which all single and double logarithms are re-summed. In two cases, spin-symmetry relations for the soft-overlap contributions to form factors are shown not to be broken at any order in perturbation theory by hard-scattering corrections. One-loop matching calculations in the two effective theories are performed in sample cases, for which the relative importance of renormalization-group evolution and matching corrections is investigated. The asymptotic behavior of Sudakov logarithms appearing in the coefficient functions of the soft-overlap and hard-scattering contributions to form factors is analyzed. (author)

Heavy Flavor Physics in Heavy-Ion Collisions with STAR Heavy Flavor Tracker

International Nuclear Information System (INIS)

Yifei Zhang

2010-01-01

Heavy quarks are a unique tool to probe the strongly interacting matter created in relativistic heavy-ion collisions at RHIC energies. Due to their large mass, energetic heavy quarks are predicted to lose less energy than light quarks by gluon radiation when they traverse a Quark-Gluon Plasma. In contrast, recent measurements of non-photonic electrons from heavy quark decays at high transverse momentum (p T ) show a jet quenching level similar to that of the light hadrons. Heavy quark are produced mainly at early stage in heavy-ion collisions, thus they are proposed to probe the QCD medium and to be sensitive to bulk medium properties. Ultimately, their flow behavior may help establish whether light quarks thermalize. But due to the absence of the measurement of B-mesons and precise measurement of D-mesons, it is difficult to separate bottom and charm contributions experimentally in current non-photonic electron measurements for both spectra and elliptic flow v 2 . Therefore, topological reconstruction of D-mesons and identification of electrons from charm and bottom decays are crucial to understand the heavy flavor production and their in medium properties. The Heavy Flavor Tracker (HFT) is a micro-vertex detector utilizing active pixel sensors and silicon strip technology. The HFT will significantly extend the physics reach of the STAR experiment for precise measurement of charmed and bottom hadrons. We present a study on the open charm nuclear modification factor, elliptic flow v 2 and λ c measurement as well as the measurement of bottom mesons via a semi-leptonic decay. (author)

Multi-sources model and control algorithm of an energy management system for light electric vehicles

International Nuclear Information System (INIS)

Hannan, M.A.; Azidin, F.A.; Mohamed, A.

2012-01-01

Highlights: ► An energy management system (EMS) is developed for a scooter under normal and heavy power load conditions. ► The battery, FC, SC, EMS, DC machine and vehicle dynamics are modeled and designed for the system. ► State-based logic control algorithms provide an efficient and feasible multi-source EMS for light electric vehicles. ► Vehicle’s speed and power are closely matched with the ECE-47 driving cycle under normal and heavy load conditions. ► Sources of energy changeover occurred at 50% of the battery state of charge level in heavy load conditions. - Abstract: This paper presents the multi-sources energy models and ruled based feedback control algorithm of an energy management system (EMS) for light electric vehicle (LEV), i.e., scooters. The multiple sources of energy, such as a battery, fuel cell (FC) and super-capacitor (SC), EMS and power controller, DC machine and vehicle dynamics are designed and modeled using MATLAB/SIMULINK. The developed control strategies continuously support the EMS of the multiple sources of energy for a scooter under normal and heavy power load conditions. The performance of the proposed system is analyzed and compared with that of the ECE-47 test drive cycle in terms of vehicle speed and load power. The results show that the designed vehicle’s speed and load power closely match those of the ECE-47 test driving cycle under normal and heavy load conditions. This study’s results suggest that the proposed control algorithm provides an efficient and feasible EMS for LEV.

A see-saw mechanism with light sterile neutrinos

International Nuclear Information System (INIS)

McKellar, B.H.J.; Garbutt, M.; Stephenson, G.J.; Goldman, T.

2001-01-01

The usual see-saw mechanism for the generation of light neutrino masses is based on the assumption that all of the flavours of right-handed (more properly, sterile) neutrinos are heavy. If the sterile Majorana mass matrix is singular, one or more of the sterile neutrinos will have zero mass before mixing with the active (left-handed) neutrinos and be light after that mixing is introduced In particular, a rank 1 sterile mass matrix leads naturally to two pseudo-Dirac pairs, one very light active Majorana neutrino and one heavy sterile Majorana neutrino. For any pattern of Dirac masses, there exists a region of parameter space in which the two pseudo-Dirac pairs are nearly degenerate in mass. This, in turn, leads to large amplitude mixing of active states as well as mixing into sterile states

Effects of Photonic Crystals on the Light Output of Heavy Inorganic Scintillators

CERN Document Server

Knapitsch, Arno; Fabjan, Christian W; Leclercq, Jean-Louis; Letartre, Xavier; Mazurczyk, Radoslaw; Lecoq, Paul

2013-01-01

Photonic crystals (PhCs) are optical materials which can affect the propagation of light in multiple ways. In recent years PhCs contributed to major technological developments in the field of semiconductor lasers, light emitting diodes and photovoltaic applications. In our case we are investigating the capabilities of photonic crystal slabs with the aim to improve the performance of heavy inorganic scintillators. To study the combination of scintillators and PhCs we use a Monte-Carlo program to simulate the light propagation inside a scintillator and a rigorous coupled wave analysis (RCWA) framework to analyse the optical PhC properties. The simulations show light output improvements of a wide range of scintillating materials due to light scattering effects of the PhC slabs. First samples have been produced on top of 1.2 × 2.6 × 5 mm LSO (cerium-doped Lutetium Oxyorthosilicate, Lu_2SiO_5:Ce^3+) scintillators using electron beam lithography and reactive ion etching (RIE). Our samples show a 30-60% light outp...

Effects of chronic lead intoxication on rat serotoninergic system and anxiety behavior.

Science.gov (United States)

Sansar, Wafa; Bouyatas, My Mustapha; Ahboucha, Samir; Gamrani, Halima

2012-01-01

Chronic lead exposure has been shown to produce behavioral disturbances in human and animal models. These disturbances are associated with alterations in monoaminergic neurotransmission in the central nervous system (CNS), some of which have been attributed to serotonin (5-HT). This study was undertaken to investigate the chronic effects of lead exposure on the serotoninergic system in the dorsal raphe nucleus (DRN) and the consequences of its toxicity on rat behavior. Adult male Wistar rats were chronically exposed for 3 months to 0.5% lead acetate in drinking water. The serotoninergic system was evaluated using immunohistochemistry and the anxiety behavior was assessed by the light/dark box test. The results show that chronic lead exposure induces a significant increase of blood and brain lead levels in treated rats compared with controls. The density of the immunoreactive serotoninergic cell bodies was significantly higher in treated rats in all parts of the DRN. Assessment of animal behavior using the light/dark box test showed that lead-treated rats spent significantly more time in the light chamber compared with controls (P=0.001). These findings suggest that lead exposure may possibly induce increased anxiety as a consequence of changes in neuronal 5-HT content in the DRN. Copyright © 2011 Elsevier GmbH. All rights reserved.

Effective non-Coulombic power-law potential for the study of light and heavy mesons

International Nuclear Information System (INIS)

Barik, N.; Jena, S.N.

1982-01-01

From purely phenomenological considerations we have shown that it is possible to describe successfully the heavy meson spectra of cc-bar and bb-bar systems in the framework of an effective non-Coulombic power-law potential in the form V(r) = V 0 +ar/sup ν/ (with a,ν>0). The nonsingular short-distance behavior of this potential, which is in apparent contradiction with the predictions of quantum- chromodynamics, does not pose any problem in explaining the fine-hyperfine splitting, if we prescribe the spin dependence to be generated through this static confining potential in the form of an approximately equal admixture of scalar and vector parts with no contributions from the anomalous quark magnetic moments. This nonrelativistic formalsm, when extended to a unified study of the entire meson spectra including the ordinary light and the heavy mesons, gives a very good account of the meson masses, fine-hyperfine splittings, electromagnetic transition rates, and leptonic decay widths without reflecting any inadequacy in the short- and long-range behavior of this simple effective power-law potential

Investigations of the Lamb shift in heavy one and two electron systems

International Nuclear Information System (INIS)

Reuschl, Regina

2008-01-01

Experiments on the 1s Lamb-shift in heavy H-like ions and on the intra-shell transitions in heavy He-like systems have been performed. These investigations are of particular interest to verify the validity of quantum electrodynamics (QED) in extremely strong Coulomb fields. In addition, in heavy systems not only QED but also relativistic effects start to play a key role. The experiments have been performed at the gas-jet target of the experimental storage ring (ESR) at GSI. In an experiment with He-like uranium we were able to directly measure the intra-shell transition 2 3 P 2 →2 3 S 1 , in a high-Z system for the very first time. This has been achieved by combining the results from a high-resolution Bragg crystal-spectrometer and a standard planar Germanium detector. A fit of the experimental spectrum with data obtained from a simulation shows, the theoretical predictions describe the transition dynamics very well in this two-electron system. Another experiment has been performed on H-like lead to investigate the 1s Lamb-shift in heavy H-like systems. Here, a high-resolution Laue crystal-spectrometer has been commissioned together with novel high-resolution two dimensional micro-strip Ge-detectors. The combination of both instruments is a very promising tool for future high-precision X-ray experiments. (orig.)

Study of elastic scattering between heavy ions. Reaction channel influence

International Nuclear Information System (INIS)

Doubre, Hubert.

1978-01-01

The role of absorption on the behavior of heavy ion angular distributions and excitaton functions has been investigated on light and medium mass systems. Comparison between 20 Ne+ 12 C and 16 O+ 16 O systems which lead to the same compound nucleus, shows that it originates from the direct channels strongly coupled to the entrance channel. Structures in the excitation functions occur for almost all the light systems and it is shown that the damping observed for heavier systems such as 40 Ca+ 40 Ca, essentially results on the predominance of Coulomb effects which hide the nuclear structure effects. Thus no valuable information on the details of S-matrix can be extracted for such an heavy system. A coherent description of the elastic scattering, based on a splitting of the scattering amplitude into two components, the modulus of each component varying smoothly as a function of energy and angle. The interference between these sub-amplitudes give rise to interference effects in angular distributions and excitation functions. The study of the main reaction channels of the 40 Ca+ 40 Ca system - i.e. deep inelastic reactions and fusion - also shows that the closed-shell nature of the interacting nuclei does not play any role in these processes due to the excitation processes in the first stage of the reactions which destroy the specific structure of the nuclei [fr

Dynamical limitations to heavy ion fusion

International Nuclear Information System (INIS)

Back, B.B.

1983-01-01

Dynamical limitations to heavy ion fusion reaction are considered. The experimental signatures and the importance of a quasi-fission process are examined. The anaular distributions of fission fragments for the 32 S+ 208 Pb and 16 O+ 238 U systems are presented. It is shown that the observations of quasi-fission for even rather ''light'' heavy ions poeess severe limitations on the fusion process. This result may consequently be responsible for the lack of success of the search for super heavy elements in heavy ion fusion reactions

Potential to reduce emissions of sulphur dioxide through reducing sulphur levels in heavy and light fuel oils - a discussion paper

International Nuclear Information System (INIS)

Tushingham, M.; Bellamy, J.

2001-01-01

Background information on the sulphur levels in light fuel oil (used in residential heating) and heavy fuel oil (used as industrial fuel oil) is provided. In addition to the description of sulphur levels in light and heavy fuel oils, the report also provides a summary of regulatory limits in Canada and elsewhere, and a description of the emission benefits of decreasing sulphur in fuels. 4 refs., 10 tabs., 12 figs

Health Assessment of Heavy Metal Pollution (Cadmium, Lead, Arsenic in Citrus Marketed in Tehran, Iran, 2015

Directory of Open Access Journals (Sweden)

Razieh Saleh

2017-03-01

Full Text Available Background & Aims of the Study: Today, the environment pollution with heavy metals has increased. It is important to study various types of pollutions specially those regarding fruits. The effect of pollutions on food safety for human consumption is a global concern.  This study was conducted for health assessment of heavy metals pollution (cadmium, lead, and arsenic in citrus marketed in Tehran, Iran in 2015. Materials & Methods: After collecting and preparing 2 samples from each citrus species (tangerine, grapefruit, sweet lime, sour orange, orange with acid digestion method, the citrus pulp and peel were surveyed. Inductively coupled plasma optical emission spectrometry (ICP-OES was used to determine the concentrations of heavy metals with three replications. Moreover, SPSS version 19 was employed to perform statistical analysis. Results: The results showed that the concentration average of Cadmium, Lead and Arsenic in citrus samples of the pulp parts were 19.73, 42.95 and 2.30 mg/kg and in peel parts were 20.09, 42.71 and 2.12 mg/kg, respectively. The average concentrations of heavy metals were higher than WHO maximum permissible limits. Conclusions: Based on these results, consumption of citrus species has no adverse effect on the consumers’ health (except Sweet lime, Orange, Tangerine and Grapefruit in lead is risky for adults and Sweet lime and Orange that Health Index in Lead and Arsenic and Sour Orange, Tangerine and Grapefruit that Health Index in Lead is more than 1 and is risky for children. Thus, individuals living in Tehran should be cautious about using these citrus fruits and researchers should try to obtain national standards in the field of entering these metals to food in environmental conditions that are in Iran.

Concordance-based Kendall's Correlation for Computationally-Light vs. Computationally-Heavy Centrality Metrics: Lower Bound for Correlation

Directory of Open Access Journals (Sweden)

Natarajan Meghanathan

2017-01-01

Full Text Available We identify three different levels of correlation (pair-wise relative ordering, network-wide ranking and linear regression that could be assessed between a computationally-light centrality metric and a computationally-heavy centrality metric for real-world networks. The Kendall's concordance-based correlation measure could be used to quantitatively assess how well we could consider the relative ordering of two vertices vi and vj with respect to a computationally-light centrality metric as the relative ordering of the same two vertices with respect to a computationally-heavy centrality metric. We hypothesize that the pair-wise relative ordering (concordance-based assessment of the correlation between centrality metrics is the most strictest of all the three levels of correlation and claim that the Kendall's concordance-based correlation coefficient will be lower than the correlation coefficient observed with the more relaxed levels of correlation measures (linear regression-based Pearson's product-moment correlation coefficient and the network wide ranking-based Spearman's correlation coefficient. We validate our hypothesis by evaluating the three correlation coefficients between two sets of centrality metrics: the computationally-light degree and local clustering coefficient complement-based degree centrality metrics and the computationally-heavy eigenvector centrality, betweenness centrality and closeness centrality metrics for a diverse collection of 50 real-world networks.

Status and prospects for lattice calculations in heavy quark physics

International Nuclear Information System (INIS)

Wittig, H.; Forschungszentrum Juelich GmbH

1996-06-01

The current status of lattice calculation of weak matrix elements for heavy quark systems is reviewed. After an assessment of systematic errors in present simulations, results for the B meson decay constant, the B parameter B B and semi-leptonic heavy-to-light and heavy-to-heavy transitions are discussed. The final topic are lattice results for heavy baryon spectroscopy. (orig.)

Emission of high-energy, light particles from intermediate-energy heavy-ion reactions

International Nuclear Information System (INIS)

Ball, J.B.; Auble, R.L.

1982-01-01

One of the early surprises in examining reaction products from heavy ion reactions at 10 MeV/nucleon and above was the large yield of light particles emitted and the high energies to which the spectra of these particles extended. The interpretation of the origin of the high energy light ions has evolved from a picture of projectile excitation and subsequent evaporation to one of pre-equilibrium (or nonequilibrium) emission. The time scale for particle emission has thus moved from one that occurs following the initial collision to one that occurs at the very early stages of the collision. Research at ORNL on this phenomenon is reviewed

The future for heavy crude oil

International Nuclear Information System (INIS)

Horsnell, P.

1995-01-01

The expectation, still held in 1993, that the light oil-heavy crude oil differential would go on increasing in favour of light oil has not been fulfilled. Current perceptions are that heavy oil will continue to be relatively strong and there is no inevitable upward trend in light-heavy crude differentials. Non-OPEC production has grown significantly lighter overall in recent years and is likely to continue so for several more years. This is due to expanded light oil production in the North Sea, Latin America and the Far East, and contractions in heavy oil production in Russia and the USA. OPEC production has also become lighter with, in particular, an expansion in light oil and contraction in heavy grades from Saudi Arabia. At the same time, the nature of the demand from refineries has changed with the introduction of new units designed to process the residium from heavy oil distillation. Thus the supply of light oil has expanded while demand for it has contracted with the reverse being true for heavy oil. (2 figures, 1 table) (UK)

One-dimensional organic lead halide perovskites with efficient bluish white-light emission

Science.gov (United States)

Yuan, Zhao; Zhou, Chenkun; Tian, Yu; Shu, Yu; Messier, Joshua; Wang, Jamie C.; van de Burgt, Lambertus J.; Kountouriotis, Konstantinos; Xin, Yan; Holt, Ethan; Schanze, Kirk; Clark, Ronald; Siegrist, Theo; Ma, Biwu

2017-01-01

Organic-inorganic hybrid metal halide perovskites, an emerging class of solution processable photoactive materials, welcome a new member with a one-dimensional structure. Herein we report the synthesis, crystal structure and photophysical properties of one-dimensional organic lead bromide perovskites, C4N2H14PbBr4, in which the edge sharing octahedral lead bromide chains [PbBr4 2-]∞ are surrounded by the organic cations C4N2H14 2+ to form the bulk assembly of core-shell quantum wires. This unique one-dimensional structure enables strong quantum confinement with the formation of self-trapped excited states that give efficient bluish white-light emissions with photoluminescence quantum efficiencies of approximately 20% for the bulk single crystals and 12% for the microscale crystals. This work verifies once again that one-dimensional systems are favourable for exciton self-trapping to produce highly efficient below-gap broadband luminescence, and opens up a new route towards superior light emitters based on bulk quantum materials.

Elastic and radiative heavy quark interactions in ultra-relativistic heavy-ion collisions

International Nuclear Information System (INIS)

Uphoff, Jan; Fochler, Oliver; Xu, Zhe; Greiner, Carsten

2015-01-01

Elastic and radiative heavy quark interactions with light partons are studied with the partonic transport model named the Boltzmann approach to multiparton scatterings (BAMPSs). After calculating the cross section of radiative processes for finite masses in the improved Gunion–Bertsch approximation and verifying this calculation by comparing to the exact result, we study elastic and radiative heavy quark energy loss in a static medium of quarks and gluons. Furthermore, the full 3 + 1D space–time evolution of gluons, light quarks, and heavy quarks in ultra-relativistic heavy-ion collisions at the BNL Relativistic Heavy-Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) are calculated with BAMPS including elastic and radiative heavy flavor interactions. Treating light and heavy particles on the same footing in the same framework, we find that the experimentally measured nuclear modification factor of charged hadrons and D mesons at the LHC can be simultaneously described. In addition, we calculate the heavy flavor evolution with an improved screening procedure from hard-thermal-loop calculations and confront the results with experimental data of the nuclear modification factor and the elliptic flow of heavy flavor particles at the RHIC and the LHC. (paper)

QCD-oriented Bethe-Salpeter dynamics for all flavours, light and heavy

International Nuclear Information System (INIS)

Mitra, A.N.

1987-01-01

A QCD oriented Bethe-Salpeter approach with a vector-like confinement which looks harmonic in the instantaneous approximation (IA), was found to describe several features of qanti q and qqq systems (mass spectra and structural properties) adequately, with little extra assumptions. The model had the following drawbacks: (a) The IA, being non-covariant, had restricted the application of the model to slow hadrons; (b) The zero-point energies were poorly described without additional assumptions; (c) The predicted Qanti Q spacings were too large for the data. These limitations have recently been overcome and the model now has a wide sweep of successful predictions, not only on the mass spectra for both light and heavy sectors, but also for transition amplitudes involving fast moving hadrons. A sketchy but consolidated account is given of the main features of the model (as modified through the new assumptions) and the nature of its successes on the experimental front (mostly mass spectra) are indicated. 20 refs

Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity

DEFF Research Database (Denmark)

Holm, L.; Reitelseder, S.; Pedersen, T.G.

2008-01-01

resonance imaging, muscle biopsies were obtained bilaterally from vastus lateralis for determination of myosin heavy chain (MHC) composition, and maximal muscle strength was assessed by 1RM testing and in an isokinetic dynamometer at 60 degrees /s. Quadriceps muscle cross-sectional area increased (P ...Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same...... individual trained one leg at 70% of one-repetition maximum (1RM) (heavy load, HL) while training the other leg at 15.5% 1RM (light load, LL). Eleven sedentary men (age 25 +/- 1 yr) trained for 12 wk at three times/week. Before and after the intervention muscle hypertrophy was determined by magnetic...

Heavy Ion Physics at CMS

CERN Document Server

Veres, Gabor

2017-01-01

In the present proceedings recent heavy ion results from the Compact Muon Solenoid collaboration at the LHC are presented. These contain comparisons between small and large collision systems, as well as studies of energy evolution, thus include data collected in proton-proton collisions at 13 TeV (2015 and 2016), proton-proton and lead-lead collisions at 5 TeV (2015), and proton-lead collisions at 5 TeV and 8 TeV (2016) center-of-mass energy per nucleon pair. They provide new insights into the properties of the extremely high density and high temperature matter created in heavy ion collisions, while pointing out similarities and differences in comparison to smaller collision systems. These include gluon distribution functions in the lead nucleus; the azimuthal anisotropy of final state particle distributions in all the three different collision systems; charge separation signals from proton-lead collisions and consequences for the Chiral Magnetic Effect; new studies of parton energy loss and its dependence on...

Symmetric splitting of very light systems

International Nuclear Information System (INIS)

Grotowski, K.; Majka, Z.; Planeta, R.

1985-01-01

Fission reactions that produce fragments close to one half the mass of the composite system are traditionally observed in heavy nuclei. In light systems, symmetric splitting is rarely observed and poorly understood. It would be interesting to verify the existence of the symmetric splitting of compound nuclei with A 12 C + 40 Ca, 141 MeV 9 Be + 40 Ca and 153 MeV 6 Li + 40 Ca. The out-of-plane correlation of symmetric products was also measured for the reaction 186 MeV 12 C + 40 Ca. The coincidence measurements of the 12 C + 40 Ca system demonstrated that essentially all of the inclusive yield of symmetric products around 40 0 results from a binary decay. To characterize the dependence of the symmetric splitting process on the excitation energy of the 12 C + 40 C system, inclusive measurements were made at bombarding energies of 74, 132, 162, and 185 MeV

Diagonal form factors and hexagon form factorsII. Non-BPS light operator

International Nuclear Information System (INIS)

Jiang, Yunfeng

2017-01-01

We study the asymptotic volume dependence of the heavy-heavy-light three-point functions in the N=4 Super-Yang-Mills theory using the hexagon bootstrap approach, where the volume is the length of the heavy operator. We extend the analysis of our previous short letter http://dx.doi.org/10.1007/JHEP07(2016)120 to the general case where the heavy operators can be in any rank one sector and the light operator being a generic non-BPS operator. We prove the conjecture of Bajnok, Janik and Wereszczynski http://dx.doi.org/10.1007/JHEP09(2014)050 up to leading finite size corrections.

Diagonal form factors and hexagon form factorsII. Non-BPS light operator

Energy Technology Data Exchange (ETDEWEB)

Jiang, Yunfeng [Institut für Theoretische Physik, ETH Zürich,Wolfgang Pauli Strasse 27, CH-8093 Zürich (Switzerland)

2017-01-05

We study the asymptotic volume dependence of the heavy-heavy-light three-point functions in the N=4 Super-Yang-Mills theory using the hexagon bootstrap approach, where the volume is the length of the heavy operator. We extend the analysis of our previous short letter http://dx.doi.org/10.1007/JHEP07(2016)120 to the general case where the heavy operators can be in any rank one sector and the light operator being a generic non-BPS operator. We prove the conjecture of Bajnok, Janik and Wereszczynski http://dx.doi.org/10.1007/JHEP09(2014)050 up to leading finite size corrections.

Heavy Metals Levels in Soil and Vegetables in Different Growing Systems

Directory of Open Access Journals (Sweden)

Hura C.

2013-04-01

Full Text Available The current project deals with an issue of actuality and scientific/technical necessity and aims to assess the factors contributing to the vulnerability of ecological systems and therefore endangering/compromising food safety. The goals of this ongoing study are to address the main risk factors on ecological system with particular regards to fresh growing vegetables and to establish technical monitoring system(s with a view to increase food safety. Herein, the authors present the research results obtained in 2011 in SIECOLEG Project regarding the assessment of some heavy metals (mainly lead, cadmium, cooper, and manganese of 80 samples soils and 25 samples vegetables from some ecological system. The concentrations of heavy metals were measured by Atomic absorption spectrometer (AAS Schimadzu 6300 - with graphite furnace atomizer and autosampler. In soil: lead and cadmium concentrations ranged from 4.51 to 6.58 mg/kg and from 0.14 to 0.4 mg/kg, respectively. Cooper and manganese concentrations ranged from 20.73 to 6.58 mg/kg and from 218.1 to 298.3 mg/kg, respectively. In vegetables (tomatoes, cucumber, peppers, eggplant, cabbage: lead concentrations ranged from 0.0 (tomatoes to 4.35 mg/kg (cabbage; cooper concentrations ranged from 0.2 mg/kg (cucumber to 0.80 mg/kg (eggplant; manganese concentrations ranged from 0.0 mg/kg (tomatoes to 0.60 mg/kg (eggplant. Cadmium was not detected in any of analysed vegetable samples. Under these circumstances, the project intends to demonstrate the extent of this vulnerability and to elaborate measures for controlling and diminishing the effects of the involved factors in order to increase food safety and security for ecological fresh vegetables

Spectral flow of trimer states of two heavy impurities and one light condensed boson

DEFF Research Database (Denmark)

Zinner, Nikolaj Thomas

2014-01-01

The spectral flow of three-body (trimer) states consisting of two heavy (impurity) particles sitting in a condensate of light bosons is considered. Assuming that the condensate is weakly interaction and that an impurity and a boson have a zero-range two-body interaction, we use the Born...

Reduction of light oil usage as power fluid for jet pumping in deep heavy oil reservoirs

Energy Technology Data Exchange (ETDEWEB)

Chen, S.; Li, H.; Yang, D. [Society of Petroleum Engineers, Canadian Section, Calgary, AB (Canada)]|[Regina Univ., SK (Canada); Zhang, Q. [China Univ. of Petroleum, Dongying, Shandong (China); He, J. [China National Petroleum Corp., Haidan District, Beijing (China). PetroChina Tarim Oilfield Co.

2008-10-15

In deep heavy oil reservoirs, reservoir fluid can flow more easily in the formation as well as around the bottomhole. However, during its path along the production string, viscosity of the reservoir fluid increases dramatically due to heat loss and release of the dissolved gas, resulting in significant pressure drop along the wellbore. Artificial lifting methods need to be adopted to pump the reservoir fluids to the surface. This paper discussed the development of a new technique for reducing the amount of light oil used for jet pumping in deep heavy oil wells. Two approaches were discussed. Approach A uses the light oil as a power fluid first to obtain produced fluid with lower viscosity, and then the produced fluid is reinjected into the well as a power fluid. The process continues until the viscosity of the produced fluid is too high to be utilized. Approach B combines a portion of the produced fluid with the light oil at a reasonable ratio and then the produced fluid-light oil mixture is used as the power fluid for deep heavy oil well production. The viscosity of the blended power fluid continue to increase and eventually reach equilibrium. The paper presented the detailed processes of both approaches in order to indicate how to apply them in field applications. Theoretic models were also developed and presented to determine the key parameters in the field operations. A field case was also presented and a comparison and analysis between the two approaches were discussed. It was concluded from the field applications that, with a certain amount of light oil, the amount of reservoir fluid produced by using the new technique could be 3 times higher than that of the conventional jet pumping method. 17 refs., 3 tabs., 6 figs.

Light-Front QCD

Energy Technology Data Exchange (ETDEWEB)

Brodsky, S.

2004-11-30

In these lectures, I survey a number of applications of light-front methods to hadron and nuclear physics phenomenology and dynamics, including light-front statistical physics. Light-front Fock-state wavefunctions provide a frame-independent representation of hadrons in terms of their fundamental quark and gluon degrees of freedom. Nonperturbative methods for computing LFWFs in QCD are discussed, including string/gauge duality which predicts the power-law fall-off at high momentum transfer of light-front Fock-state hadronic wavefunctions with an arbitrary number of constituents and orbital angular momentum. The AdS/CFT correspondence has important implications for hadron phenomenology in the conformal limit, including an all-orders derivation of counting rules for exclusive processes. One can also compute the hadronic spectrum of near-conformal QCD assuming a truncated AdS/CFT space. Given the LFWFs, one can compute form factors, heavy hadron decay amplitudes, hadron distribution amplitudes, and the generalized parton distributions underlying deeply virtual Compton scattering. The quantum fluctuations represented by the light-front Fock expansion leads to novel QCD phenomena such as color transparency, intrinsic heavy quark distributions, diffractive dissociation, and hidden-color components of nuclear wavefunctions. A new test of hidden color in deuteron photodisintegration is proposed. The origin of leading-twist phenomena such as the diffractive component of deep inelastic scattering, single-spin asymmetries, nuclear shadowing and antishadowing is also discussed; these phenomena cannot be described by light-front wavefunctions of the target computed in isolation. Part of the anomalous NuTeV results for the weak mixing angle {theta}{sub W} could be due to the non-universality of nuclear antishadowing for charged and neutral currents.

Decay constants and radiative decays of heavy mesons in light-front quark model

International Nuclear Information System (INIS)

Choi, Ho-Meoyng

2007-01-01

We investigate the magnetic dipole decays V→Pγ of various heavy-flavored mesons such as (D,D*,D s ,D s *,η c ,J/ψ) and (B,B*,B s ,B s *,η b ,Υ) using the light-front quark model constrained by the variational principle for the QCD-motivated effective Hamiltonian. The momentum dependent form factors F VP (q 2 ) for V→Pγ* decays are obtained in the q + =0 frame and then analytically continued to the timelike region by changing q perpendicular to iq perpendicular in the form factors. The coupling constant g VPγ for real photon case is then obtained in the limit as q 2 →0, i.e. g VPγ =F VP (q 2 =0). The weak decay constants of heavy pseudoscalar and vector mesons are also calculated. Our numerical results for the decay constants and radiative decay widths for the heavy-flavored mesons are overall in good agreement with the available experimental data as well as other theoretical model calculations

Properties of Doubly Heavy Baryons in the Relativistic Quark Model

International Nuclear Information System (INIS)

Ebert, D.; Faustov, R.N.; Galkin, V.O.; Martynenko, A.P.

2005-01-01

Mass spectra and semileptonic decay rates of baryons consisting of two heavy (b or c) and one light quark are calculated in the framework of the relativistic quark model. The doubly heavy baryons are treated in the quark-diquark approximation. The ground and excited states of both the diquark and quark-diquark bound systems are considered. The quark-diquark potential is constructed. The light quark is treated completely relativistically, while the expansion in the inverse heavy-quark mass is used. The weak transition amplitudes of heavy diquarks bb and bc going, respectively, to bc and cc are explicitly expressed through the overlap integrals of the diquark wave functions in the whole accessible kinematic range. The relativistic baryon wave functions of the quark-diquark bound system are used for the calculation of the decay matrix elements, the Isgur-Wise function, and decay rates in the heavy-quark limit

Role of light and heavy minerals on natural radioactivity level of high background radiation area, Kerala, India.

Science.gov (United States)

Ramasamy, V; Sundarrajan, M; Suresh, G; Paramasivam, K; Meenakshisundaram, V

2014-02-01

Natural radionuclides ((238)U, (232)Th and (40)K) concentrations and eight different radiological parameters have been analyzed for the beach sediments of Kerala with an aim of evaluating the radiation hazards. Activity concentrations ((238)U and (232)Th) and all the radiological parameters in most of the sites have higher values than recommended values. The Kerala beach sediments pose significant radiological threat to the people living in the area and tourists going to the beaches for recreation or to the sailors and fishermen involved in their activities in the study area. In order to know the light mineral characterization of the present sediments, mineralogical analysis has been carried out using Fourier transform infrared (FTIR) spectroscopic technique. The eight different minerals are identified and they are characterized. Among the various observed minerals, the minerals such as quartz, microcline feldspar, kaolinite and calcite are major minerals. The relative distribution of major minerals is determined by calculating extinction co-efficient and the values show that the amount of quartz is higher than calcite and much higher than microcline feldspar. Crystallinity index is calculated to know the crystalline nature of quartz present in the sediments. Heavy mineral separation analysis has been carried out to know the total heavy mineral (THM) percentage. This analysis revealed the presence of nine heavy minerals. The minerals such as monazite, zircon, magnetite and illmenite are predominant. Due to the rapid and extreme changes occur in highly dynamic environments of sandy beaches, quantities of major light and heavy minerals are widely varied from site to site. Granulometric analysis shows that the sand is major content. Multivariate statistical (Pearson correlation, cluster and factor) analysis has been carried out to know the effect of mineralogy on radionuclide concentrations. The present study concluded that heavy minerals induce the (238)U and (232)Th

Survey of heavy metal pollution (copper, lead, zinc, cadmium, iron and manganese in drinking water resources of Nurabad city, Lorestan, Iran 2013

Directory of Open Access Journals (Sweden)

GHodratolah Shams Khorramabadi

2016-09-01

Full Text Available Background: Healthy water passes through the pipelines from supply resources to consuming places in which passing from these stages may cause some cases of contamination like heavy metal contamination. Therefore, the aim of this study was to evaluate the contamination of heavy metals (copper, lead, zinc, cadmium, iron, and manganese in water resources of Nurabad city of Lorestan in 2013. Materials and Methods: In this cross-sectional study, samples were collected from 7 wells of drinking water and 2 water storage tanks during 6 months in Nurabad. So that, heavy metal parameters such as copper, lead, zinc, cadmium, iron, and manganese were measured using an atomic absorption device and also electrical conductivity, sulfate, chloride and total dissolved solids were also measured in accordance with standard methods. Results: Results indicated that the concentration of studied metals in water sources was lower than the national standards and World Health Organization standard, and in the water supply system the concentration of some metals was more than standard level. Moreover, the results showed that the concentration of studied heavy metals were more in winter than in autumn. Conclusion: Generally, in the water resources of Nurabad city the concentration of studied heavy metals was lower than the national standards and World Health Organization standard and there are not problems for water consumers. However, due to public health and the presence of a high concentration of these metals in the distribution supply, the heavy metal concentration in drinking water of this region should be monitored regularly by responsible organizations.

Study of the 6Li+16O light heavy-ion system around the Coulomb barrier

International Nuclear Information System (INIS)

Glasner, K.; Ricken, L.; Kuhlmann, E.

1986-01-01

Total cross sections of the light heavy-ion reactions 16 O( 6 Li,p) 21 Ne, i=0-10, have been measured for beam energies Esub(Li)=4.5-8.0 MeV in steps of 100 keV. Additional excitation functions of the inclusive reactions 16 O( 6 Li,xy), x=p, n and α, were taken for Esub(li)=4.1-12.5 MeV. The 6 Li+ 16 O reaction can be understood as a predominant compound-nucleus process as extensive Hauser-Feshbach calculations show. A comprehensive statistical analysis yields a coherence width GAMMA=130+-20 keV for Esub(x)( 22 Na)approx.=19 MeV. Statistically significant deviations from pure fluctuation phenomena are found in most excitation functions at Esub(x)( 22 Na)=17.9, 18.4, 19.2 and 20.2 MeV. Interpreting these structures with widths 400<=GAMMAsub(tot)<=800 keV as intermediate-width resonances in terms of rotational band, tentative spin assignments can be given. (orig.)

Local-duality QCD sum rules for strong isospin breaking in the decay constants of heavy-light mesons

Energy Technology Data Exchange (ETDEWEB)

Lucha, Wolfgang [Austrian Academy of Sciences, Institute for High Energy Physics, Vienna (Austria); Melikhov, Dmitri [Austrian Academy of Sciences, Institute for High Energy Physics, Vienna (Austria); M.V. Lomonosov Moscow State University, D.V. Skobeltsyn Institute of Nuclear Physics, Moscow (Russian Federation); University of Vienna, Faculty of Physics, Vienna (Austria); Simula, Silvano [Istituto Nazionale di Fisica Nucleare, Sezione di Roma Tre, Rome (Italy)

2018-02-15

We discuss the leptonic decay constants of heavy-light mesons by means of Borel QCD sum rules in the local-duality (LD) limit of infinitely large Borel mass parameter. In this limit, for an appropriate choice of the invariant structures in the QCD correlation functions, all vacuum-condensate contributions vanish and all nonperturbative effects are contained in only one quantity, the effective threshold. We study properties of the LD effective thresholds in the limits of large heavy-quark mass m{sub Q} and small light-quark mass m{sub q}. In the heavy-quark limit, we clarify the role played by the radiative corrections in the effective threshold for reproducing the pQCD expansion of the decay constants of pseudoscalar and vector mesons. We show that the dependence of the meson decay constants on m{sub q} arises predominantly (at the level of 70-80%) from the calculable m{sub q}-dependence of the perturbative spectral densities. Making use of the lattice QCD results for the decay constants of nonstrange and strange pseudoscalar and vector heavy mesons, we obtain solid predictions for the decay constants of heavy-light mesons as functions of m{sub q} in the range from a few to 100 MeV and evaluate the corresponding strong isospin-breaking effects: f{sub D{sup +}} - f{sub D{sup 0}} = (0.96 ± 0.09) MeV, f{sub D}{sup {sub *}{sub +}} - f{sub D}{sup {sub *}{sub 0}} = (1.18 ± 0.35) MeV, f{sub B{sup 0}} - f{sub B{sup +}} = (1.01 ± 0.10) MeV, f{sub B}{sup {sub *}{sub 0}} - f{sub B}{sup {sub *}{sub +}} = (0.89 ± 0.30) MeV. (orig.)

Heavy Metal Exposure and Metabolic Syndrome: Evidence from Human and Model System Studies.

Science.gov (United States)

Planchart, Antonio; Green, Adrian; Hoyo, Cathrine; Mattingly, Carolyn J

2018-03-01

Metabolic syndrome (MS) describes the co-occurrence of conditions that increase one's risk for heart disease and other disorders such as diabetes and stroke. The worldwide increase in the prevalence of MS cannot be fully explained by lifestyle factors such as sedentary behavior and caloric intake alone. Environmental exposures, such as heavy metals, have been implicated, but results are conflicting and possible mechanisms remain unclear. To assess recent progress in determining a possible role between heavy metal exposure and MS, we reviewed epidemiological and model system data for cadmium (Cd), lead (Pb), and mercury (Hg) from the last decade. Data from 36 epidemiological studies involving 17 unique countries/regions and 13 studies leveraging model systems are included in this review. Epidemiological and model system studies support a possible association between heavy metal exposure and MS or comorbid conditions; however, results remain conflicting. Epidemiological studies were predominantly cross-sectional and collectively, they highlight a global interest in this question and reveal evidence of differential susceptibility by sex and age to heavy metal exposures. In vivo studies in rats and mice and in vitro cell-based assays provide insights into potential mechanisms of action relevant to MS including altered regulation of lipid and glucose homeostasis, adipogenesis, and oxidative stress. Heavy metal exposure may contribute to MS or comorbid conditions; however, available data are conflicting. Causal inference remains challenging as epidemiological data are largely cross-sectional; and variation in study design, including samples used for heavy metal measurements, age of subjects at which MS outcomes are measured; the scope and treatment of confounding factors; and the population demographics vary widely. Prospective studies, standardization or increased consistency across study designs and reporting, and consideration of molecular mechanisms informed by model

Overview of the Safety Issues Associated with the Compressed Natural Gas Fuel System and Electric Drive System in a Heavy Hybrid Electric Vehicle

Energy Technology Data Exchange (ETDEWEB)

Nelson, S.C.

2002-11-14

This report evaluates the hazards that are unique to a compressed-natural-gas (CNG)-fueled heavy hybrid electric vehicle (HEV) design compared with a conventional heavy vehicle. The unique design features of the heavy HEV are the CNG fuel system for the internal-combustion engine (ICE) and the electric drive system. This report addresses safety issues with the CNG fuel system and the electric drive system. Vehicles on U. S. highways have been propelled by ICEs for several decades. Heavy-duty vehicles have typically been fueled by diesel fuel, and light-duty vehicles have been fueled by gasoline. The hazards and risks posed by ICE vehicles are well understood and have been generally accepted by the public. The economy, durability, and safety of ICE vehicles have established a standard for other types of vehicles. Heavy-duty (i.e., heavy) HEVs have recently been introduced to U. S. roadways, and the hazards posed by these heavy HEVs can be compared with the hazards posed by ICE vehicles. The benefits of heavy HEV technology are based on their potential for reduced fuel consumption and lower exhaust emissions, while the disadvantages are the higher acquisition cost and the expected higher maintenance costs (i.e., battery packs). The heavy HEV is more suited for an urban drive cycle with stop-and-go driving conditions than for steady expressway speeds. With increasing highway congestion and the resulting increased idle time, the fuel consumption advantage for heavy HEVs (compared with conventional heavy vehicles) is enhanced by the HEVs' ability to shut down. Any increase in fuel cost obviously improves the economics of a heavy HEV. The propulsion system for a heavy HEV is more complex than the propulsion system for a conventional heavy vehicle. The heavy HEV evaluated in this study has in effect two propulsion systems: an ICE fueled by CNG and an electric drive system with additional complexity and failure modes. This additional equipment will result in a less

Computer Modeling of Daylight-Integrated Photocontrol of Electric Lighting Systems

Directory of Open Access Journals (Sweden)

Richard Mistrick

2015-05-01

Full Text Available This article presents a variety of different approaches to both model and assess the performance of daylight-integrated electric lighting control systems. In these systems, the output of a controlled lighting zone is based on a light sensor reading and a calibrated control algorithm. Computer simulations can consider the simulated illuminance data generated from both the electric lighting system and a daylight delivery system whose performance is addressed using typical meteorological year (TMY weather data. Photosensor signals and the operation of a control system’s dimming algorithms are also included. Methods and metrics for evaluating simulated performance for the purpose of making informed design decisions that lead to the best possible installed system performance are presented.

Lead Apron Inspection Using Infrared Light: A Model Validation Study.

Science.gov (United States)

McKenney, Sarah E; Otero, Hansel J; Fricke, Stanley T

2018-02-01

To evaluate defect detection in radiation protective apparel, typically called lead aprons, using infrared (IR) thermal imaging. The use of IR lighting eliminates the need for access to x-ray-emitting equipment and radiation dose to the inspector. The performance of radiation workers was prospectively assessed using both a tactile inspection and the IR inspection with a lead apron phantom over a 2-month period. The phantom was a modified lead apron with a series of nine holes of increasing diameter ranging from 2 to 35 mm in accordance with typical rejection criteria. Using the tactile method, a radiation worker would feel for the defects in the lead apron. For the IR inspection, a 250-W IR light source was used to illuminate the lead apron phantom; an IR camera detected the transmitted radiation. The radiation workers evaluated two stills from the IR camera. From the 31 participants inspecting the lead apron phantom with the tactile method, only 2 participants (6%) correctly discovered all 9 holes and 1 participant reported a defect that was not there; 10 of the 20 participants (50%) correctly identified all 9 holes using the IR method. Using a weighted average, 5.4 defects were detected with the tactile method and 7.5 defects were detected with the IR method. IR light can penetrate an apron's protective outer fabric and illuminate defects below the current standard rejection size criteria. The IR method improves defect detectability as compared with the tactile method. Copyright © 2017 American College of Radiology. Published by Elsevier Inc. All rights reserved.

The association of heavy and light chain variable domains in antibodies: implications for antigen specificity.

KAUST Repository

Chailyan, Anna; Marcatili, Paolo; Tramontano, Anna

2011-01-01

of interaction between the heavy and light chain variable domains affects the relative position of the antigen-binding loops and therefore has an effect on the overall conformation of the binding site. In this article, we analyze the structure of the interface

Light and heavy touch reduces postural sway and modifies axial tone in Parkinson's disease.

Science.gov (United States)

Franzén, Erika; Paquette, Caroline; Gurfinkel, Victor; Horak, Fay

2012-10-01

Light touch with a stable object reduces postural sway by increasing axial postural tone in healthy subjects. However, it is unknown whether subjects with Parkinson's disease (PD), who have more postural sway and higher axial postural tone than healthy subjects, can benefit from haptic touch. To investigate the effect of light and heavy touch on postural stability and hip tone in subjects with PD. Fourteen subjects with mid-stage PD and 14 healthy control subjects were evaluated during quiet standing with eyes closed with their arms (a) crossed, (b) lightly touching a fixed rigid bar in front of them, and (c) firmly gripping the bar. Postural sway was measured with a forceplate, and axial hip tone was quantified using a unique device that measures the resistance of the hips to yaw rotation while maintaining active stance. Subjects with PD significantly decreased their postural sway with light or heavy touch (P touch, hip tone was larger in PD subjects. With touch, however, tone values were similar in both groups. This change in hip tone with touch was highly correlated with the initial amount of tone (PD, r = -.72 to -.95; controls, r = -.74 to -.85). The authors showed, for the first time, that subjects with PD benefit from touch similarly to control subjects and that despite higher axial postural tone, PD subjects are able to modulate their tone with touch. Future studies should investigate the complex relationship between touch and postural tone.

Interactions of 10.6 GeV/n gold nuclei with light and heavy target nuclei in nuclear emulsion

International Nuclear Information System (INIS)

Cherry, M.L.; Denes-Jones, P.

1994-03-01

We have investigated the particle production and fragmentation of nuclei participating in the interactions of 10.6 GeV/n gold nuclei in nuclear emulsions. A new criteria has been developed to distinguish between the interactions of these gold nuclei with the light (H, C, N, O) and heavy (Ag, Br) target nuclei in the emulsion. This has allowed separate analyzes of the multiplicity and pseudo-rapidity distributions of the singly charged particles emitted in Au-(H, C, N, O) and Au-(Ag, Br) interactions, as well as of the models of breakup of the projectile and target nuclei. The pseudo-rapidity distributions show strong forward asymmetries, particularly for the interactions with the light nuclei. Heavy target nuclei produce a more severe breakup of the projectile gold nucleus than do the lighter targets. A negative correlation between the number of fragments emitted from the target nuclei and the degree of centrality of the collisions has been observed, which can be attributed to the total destruction of the relatively light target nuclei by these very heavy projectile nuclei. (author). 14 refs, 11 figs, 1 tab

Heavy Flavor Production in Heavy Ion Collisions at CMS

CERN Document Server

Sun, Jian

2016-01-01

Studies of Heavy flavor production are of great interest in heavy ion collisions. In the produced medium, the binding potential between a quark and antiquark in quarkonium is screened by surrounding light quarks and antiquarks. Thus, the various quarkonium states are expected to be melt at different temperatures depending on their binding energies, which allows us to characterize the QCD phase transition. In addition, open heavy flavor production are relevant for flavor-dependence of the in-medium parton energy loss. In QCD, gluons are expected to lose more energy compared to quarks when passing through the QGP due to the larger color charge. Compared to light quarks, heavy quarks are expected to lose less radiative energy because gluon radiation is suppressed at angles smaller than the ratio of the quark mass to its energy. This dead cone effect (and its disappearance at high transverse momentum) can be studied using open heavy flavor mesons and heavy flavor tagged jets. With CMS detector, quarkonia, open he...

Neutrinoless ββ decay mediated by the exchange of light and heavy neutrinos: the role of nuclear structure correlations

Science.gov (United States)

Menéndez, J.

2018-01-01

Neutrinoless β β decay nuclear matrix elements calculated with the shell model and energy-density functional theory typically disagree by more than a factor of two in the standard scenario of light-neutrino exchange. In contrast, for a decay mediated by sterile heavy neutrinos the deviations are reduced to about 50%, an uncertainty similar to the one due to short-range effects. We compare matrix elements in the light- and heavy-neutrino-exchange channels, exploring the radial, momentum transfer and angular momentum-parity matrix element distributions, and considering transitions that involve correlated and uncorrelated nuclear states. We argue that the shorter-range heavy-neutrino exchange is less sensitive to collective nuclear correlations, and that discrepancies in matrix elements are mostly due to the treatment of long-range correlations in many-body calculations. Our analysis supports previous studies suggesting that isoscalar pairing correlations, which affect mostly the longer-range part of the neutrinoless β β decay operator, are partially responsible for the differences between nuclear matrix elements in the standard light-neutrino-exchange mechanism.

Measurements of vector boson production in lead–lead and proton–lead collisions with the ATLAS detector

International Nuclear Information System (INIS)

Grabowska-Bold, Iwona

2014-01-01

Photons and weak bosons do not interact strongly and, thus, their production yields provide direct tests of scaling with a number of binary nucleon–nucleon collisions in the heavy-ion environment. In addition, they should be sensitive to the nuclear modification of parton distribution functions (nPDF). Proton-lead collisions also provide an excellent opportunity to test nPDF in a less dense environment than lead–lead via looking at forward–backward production of weak bosons. The ATLAS detector has proven to be an excellent apparatus in measurements involving photons, electrons and muons, the latter being products of weak boson decays, in the high occupancy environment produced in heavy-ion collisions. The experiment has recorded 30nb −1 of proton–lead data and 140μb −1 of lead–lead data, both of which have similar integrated partonic luminosities. We present the prompt photon, Z and W boson yields as a function of centrality, and also differentially in transverse momentum and rapidity, in lead–lead and proton–lead collisions from the ATLAS experiment. For W ± bosons, a lepton charge asymmetry has also been studied, which may also shed light on nPDF

Heavy ion irradiation effects of polymer film on absorption of light

Energy Technology Data Exchange (ETDEWEB)

Kasai, Noboru; Seguchi, Tadao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Arakawa, Tetsuhito

1997-03-01

Ion irradiation effects on the absorption of light for three types of polymer films; polyethylene-terephthalate (PET), polyethylene-naphthalate (PEN), and polyether-ether-ketone (PEEK) were investigated by irradiation of heavy ions with Ni{sup 4+}(15MeV), O{sup 6+}(160MeV), and Ar{sup 8+}(175MeV), and compared with electron beams(EB) irradiation. The change of absorption at 400nm by a photometer was almost proportional to total dose for ions and EB. The absorption per absorbed dose was much high in Ni{sup 4+}, but rather small in O{sup 6+} and Ar{sup 8+} irradiation, and the absorption by EB irradiation was accelerated by the temperature of polymer film during irradiation. The beam heating of materials during ion irradiation was assumed, especially for Ni ion irradiation. The heavy ion irradiation effect of polymers was thought to be much affected by the ion beam heating than the linear energy transfer(LET) of radiation source. (author)

Soil heavy metals

Energy Technology Data Exchange (ETDEWEB)

Sherameti, Irena [Jena Univ. (Germany). Inst. fuer Allgemeine Botanik und Pflanzenphysiologie; Varma, Ajit (eds.) [Amity Univ., Uttar Pradesh (India). Amity Inst. of Microbial Technology; Amity Science, Technology and Innovation Foundation, Noida, UP (India)

2010-07-01

Human activities have dramatically changed the composition and organisation of soils. Industrial and urban wastes, agricultural application and also mining activities resulted in an increased concentration of heavy metals in soils. How plants and soil microorganisms cope with this situation and the sophisticated techniques developed for survival in contaminated soils is discussed in this volume. The topics presented include: the general role of heavy metals in biological soil systems; the relation of inorganic and organic pollutions; heavy metal, salt tolerance and combined effects with salinity; effects on abuscular mycorrhizal and on saprophytic soil fungi; heavy metal resistance by streptomycetes; trace element determination of environmental samples; the use of microbiological communities as indicators; phytostabilization of lead polluted sites by native plants; effects of soil earthworms on removal of heavy metals and the remediation of heavy metal contaminated tropical land. (orig.)

Complete fusion in light 'heavy ion' collisions

International Nuclear Information System (INIS)

Volant, C.; Wieleczko, J.P.

1979-01-01

In the last few years a large amount of data have been obtained on the complete fusion of light ions. One of the aim of these studies was to look for aspects which could not be explained by the macroscopic description of the fusion which works quite well for heavier systems. Indeed, it was suggested that for light systems the fusion could be sometimes limited by compound nucleus properties or by some particular structures in the entrance channel. In this talk new results on fusion experiments obtained by the Saclay group are presented

Sub-Angstrom Atomic-Resolution Imaging of Heavy Atoms to Light Atoms

Energy Technology Data Exchange (ETDEWEB)

O' Keefe, Michael A.; Shao-Horn, Yang

2003-05-23

Three decades ago John Cowley and his group at ASU achieved high-resolution electron microscope images showing the crystal unit cell contents at better than 4Angstrom resolution. Over the years, this achievement has inspired improvements in resolution that have enabled researchers to pinpoint the positions of heavy atom columns within the cell. More recently, this ability has been extended to light atoms as resolution has improved. Sub-Angstrom resolution has enabled researchers to image the columns of light atoms (carbon, oxygen and nitrogen) that are present in many complex structures. By using sub-Angstrom focal-series reconstruction of the specimen exit surface wave to image columns of cobalt, oxygen, and lithium atoms in a transition metal oxide structure commonly used as positive electrodes in lithium rechargeable batteries, we show that the range of detectable light atoms extends to lithium. HRTEM at sub-Angstrom resolution will provide the essential role of experimental verification for the emergent nanotech revolution. Our results foreshadow those to be expected from next-generation TEMs with Cs-corrected lenses and monochromated electron beams.

Thorium utilization in heavy water moderated Accelerator Driven Systems

International Nuclear Information System (INIS)

Bajpai, Anil; Degweker, S.B.; Ghosh, Biplab

2011-01-01

is a much more realistic option, since it gives us a good gain with heavy water as coolant and even with light water cooled heavy water moderated reactor, the gain is somewhat lower, but still acceptable. We show that the self sustaining cycle for a critical system gives rather low discharge burnup. To obtain higher burnup, the critical reactor needs an external feed of fissile material. We show that the accelerator driven sub-critical mode of operation gives acceptable burnup in a self sustaining cycle. (author)

Weak leptonic decay of light and heavy pseudoscalar mesons in an independent quark model

International Nuclear Information System (INIS)

Barik, N.; Dash, P.C.

1993-01-01

Weak leptonic decays of light and heavy pseudoscalar mesons are studied in a field-theoretic framework based on the independent quark model with a scalar-vector harmonic potential. Defining the quark-antiquark momentum distribution amplitude obtainable from the bound quark eigenmodes of the model with the assumption of a strong correlation between quark-antiquark momenta inside the decaying meson in its rest frame, we derive the partial decay width with correct kinematical factors from which we extract an expression for the pseudoscalar decay constants f M . Using the model parameters determined from earlier studies in the light-flavor sector and heavy-quark masses m c and m b from the hyperfine splitting of (D * ,D) and (B * ,B), we calculate the pseudoscalar decay constants. We find that while (f π ,f K )≡(138,157 MeV); (f D ,f Ds )≡(161,205 MeV), (f B ,f Bs )≡(122,154 MeV), and f Bc =221 MeV. We also obtain the partial decay widths and branching ratios for some kinematically allowed weak leptonic decay processes

Heavy baryons

International Nuclear Information System (INIS)

Koerner, J.G.

1994-06-01

We review the experimental and theoretical status of baryons containing one heavy quark. The charm and bottom baryon states are classified and their mass spectra are listed. The appropriate theoretical framework for the description of heavy baryons is the Heavy Quark Effective Theory, whose general ideas and methods are introduced and illustrated in specific examples. We present simple covariant expressions for the spin wave functions of heavy baryons including p-wave baryons. The covariant spin wave functions are used to determine the Heavy Quark Symmetry structure of flavour-changing current-induced transitions between heavy baryons as well as one-pion and one-photon transitions between heavy baryons of the same flavour. We discuss 1/m Q corrections to the current-induced transitions as well as the structure of heavy to light baryon transitions. Whenever possible we attempt to present numbers to compare with experiment by making use of further model-dependent assumptions as e.g. the constituent picture for light quarks. We highlight recent advances in the theoretical understanding of the inclusive decays of hadrons containing one heavy quark including polarization. For exclusive semileptonic decays we discuss rates, angular decay distributions and polarization effects. We provide an update of the experimental and theoretical status of lifetimes of heavy baryons and of exclusive nonleptonic two body decays of charm baryons. (orig.)

Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant

Directory of Open Access Journals (Sweden)

Zamani Abbas Ali

2012-12-01

Full Text Available Abstract The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP. Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs. Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.

Multivariate statistical assessment of heavy metal pollution sources of groundwater around a lead and zinc plant.

Science.gov (United States)

Zamani, Abbas Ali; Yaftian, Mohammad Reza; Parizanganeh, Abdolhossein

2012-12-17

The contamination of groundwater by heavy metal ions around a lead and zinc plant has been studied. As a case study groundwater contamination in Bonab Industrial Estate (Zanjan-Iran) for iron, cobalt, nickel, copper, zinc, cadmium and lead content was investigated using differential pulse polarography (DPP). Although, cobalt, copper and zinc were found correspondingly in 47.8%, 100.0%, and 100.0% of the samples, they did not contain these metals above their maximum contaminant levels (MCLs). Cadmium was detected in 65.2% of the samples and 17.4% of them were polluted by this metal. All samples contained detectable levels of lead and iron with 8.7% and 13.0% of the samples higher than their MCLs. Nickel was also found in 78.3% of the samples, out of which 8.7% were polluted. In general, the results revealed the contamination of groundwater sources in the studied zone. The higher health risks are related to lead, nickel, and cadmium ions. Multivariate statistical techniques were applied for interpreting the experimental data and giving a description for the sources. The data analysis showed correlations and similarities between investigated heavy metals and helps to classify these ion groups. Cluster analysis identified five clusters among the studied heavy metals. Cluster 1 consisted of Pb, Cu, and cluster 3 included Cd, Fe; also each of the elements Zn, Co and Ni was located in groups with single member. The same results were obtained by factor analysis. Statistical investigations revealed that anthropogenic factors and notably lead and zinc plant and pedo-geochemical pollution sources are influencing water quality in the studied area.

Heavy Chain Diseases

Science.gov (United States)

... of heavy chain produced: Alpha Gamma Mu Alpha Heavy Chain Disease Alpha heavy chain disease (IgA heavy ... the disease or lead to a remission. Gamma Heavy Chain Disease Gamma heavy chain disease (IgG heavy ...

Hyperthermal (10-500 eV) collisions of noble gases with Ni(100) surface. Comparison between light and heavy atom collisions

International Nuclear Information System (INIS)

Kim, C.

1995-01-01

Collisional events between 10-500 eV atomic beams (He, Ne, Ar, Kr, and Xe) and a Ni(100) surface are investigated by the classical trajectory method. The calculation employs a molecular dynamics approach combined with a Langevin method for treating energy dissipation to infinite solid. We find that low energy collisions of heavy atoms (Xe and Kr) are characterized by extensive many-body interactions with top layer surface atoms. On the other hand, light atom (Ne and He) collisions can be approximated as a sequence of binary collisions even at these energies. Such a difference in the collisional nature gives rise to the following consequences. Low energy heavy atoms transfer energy mostly to the surface atoms during 45 angle collision. They scatter from the surface with a narrow angular distribution centered in a supraspecular direction. The ratio of the scattered to incident particle energy rapidly decreases with increasing beam energy of heavy atoms. The sputtering yield for Ni atoms by heavy atom bombardment increases quite linearly with beam energy, which is attributed to a linear proportionality between the beam energy and the energy transfered to a surface. Near the threshold energy sputtering can occur more efficiently by light atom bombardment. The energy transfer ratio to solid continuously increases with beam energy for light atoms. For heavy projectiles, on the other hand, this ratio reaches a maximum at the energy of ca, 100 eV, above which it stays nearly constant but slightly decreases. ((orig.))

Phenomenology of heavy quark systems

International Nuclear Information System (INIS)

Gilman, F.J.

1987-03-01

The spectroscopy of heavy quark systems is examined with regards to spin independent and spin dependent potentials. It is shown that a qualitative picture exists of the spin-independent forces, and that a semi-quantitative understanding exists for the spin-dependent effects. A brief review is then given of the subject of the decays of hadrons containing heavy quarks, including weak decays at the quark level, and describing corrections to the spectator model

Covariant Spectator Theory of heavy–light and heavy mesons and the predictive power of covariant interaction kernels

Energy Technology Data Exchange (ETDEWEB)

Leitão, Sofia, E-mail: sofia.leitao@tecnico.ulisboa.pt [CFTP, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Stadler, Alfred, E-mail: stadler@uevora.pt [Departamento de Física, Universidade de Évora, 7000-671 Évora (Portugal); CFTP, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Peña, M.T., E-mail: teresa.pena@tecnico.ulisboa.pt [Departamento de Física, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); CFTP, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal); Biernat, Elmar P., E-mail: elmar.biernat@tecnico.ulisboa.pt [CFTP, Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisboa (Portugal)

2017-01-10

The Covariant Spectator Theory (CST) is used to calculate the mass spectrum and vertex functions of heavy–light and heavy mesons in Minkowski space. The covariant kernel contains Lorentz scalar, pseudoscalar, and vector contributions. The numerical calculations are performed in momentum space, where special care is taken to treat the strong singularities present in the confining kernel. The observed meson spectrum is very well reproduced after fitting a small number of model parameters. Remarkably, a fit to a few pseudoscalar meson states only, which are insensitive to spin–orbit and tensor forces and do not allow to separate the spin–spin from the central interaction, leads to essentially the same model parameters as a more general fit. This demonstrates that the covariance of the chosen interaction kernel is responsible for the very accurate prediction of the spin-dependent quark–antiquark interactions.

A positive-weight next-to-leading-order Monte Carlo for heavy flavour hadroproduction

International Nuclear Information System (INIS)

Frixione, Stefano; Ridolfi, Giovanni; Nason, Paolo

2007-01-01

We present a next-to-leading order calculation of heavy flavour production in hadronic collisions that can be interfaced to shower Monte Carlo programs. The calculation is performed in the context of the POWHEG method. It is suitable for the computation of charm, bottom and top hadroproduction. In the case of top production, spin correlations in the decay products are taken into account

Light-induced lattice expansion leads to high-efficiency perovskite solar cells

Science.gov (United States)

Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

2018-04-01

Light-induced structural dynamics plays a vital role in the physical properties, device performance, and stability of hybrid perovskite–based optoelectronic devices. We report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in situ structural and device characterizations reveal that light-induced lattice expansion benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5 to 20.5%. The lattice expansion leads to the relaxation of local lattice strain, which lowers the energetic barriers at the perovskite-contact interfaces, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion did not compromise the stability of these high-efficiency photovoltaic devices under continuous operation at full-spectrum 1-sun (100 milliwatts per square centimeter) illumination for more than 1500 hours.

Several crucial problems in evaluating spectra of baryons with two heavy quarks

International Nuclear Information System (INIS)

Tong Shengping; Ding Yibing; Guo Xinheng; Shen Pengnian; Li Xueqian; Zhang Rui

2000-01-01

The spectra of baryons which include two heavy quarks and one light quark can be treated as a two-body system, where two heavy quarks constitute a bosonic diquark. The authors derive the effective potential between the light quark and the heavy diquark. In this work authors have discussed several serious problems: (1) the operator ordering, (2) the errors caused by the non-relativistic expansion, (3) spin-spin coupling and (4) the mixing between baryon states with scalar-diquark and vector-diquark

Lighting system with thermal management system

Science.gov (United States)

Arik, Mehmet; Weaver, Stanton; Stecher, Thomas; Seeley, Charles; Kuenzler, Glenn; Wolfe, Jr., Charles; Utturkar, Yogen; Sharma, Rajdeep; Prabhakaran, Satish; Icoz, Tunc

2013-05-07

Lighting systems having unique configurations are provided. For instance, the lighting system may include a light source, a thermal management system and driver electronics, each contained within a housing structure. The light source is configured to provide illumination visible through an opening in the housing structure. The thermal management system is configured to provide an air flow, such as a unidirectional air flow, through the housing structure in order to cool the light source. The driver electronics are configured to provide power to each of the light source and the thermal management system.

Process for removing heavy metal compounds from heavy crude oil

Science.gov (United States)

Cha, Chang Y.; Boysen, John E.; Branthaver, Jan F.

1991-01-01

A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

Perturbative effect of heavy particles in an effective-Lagrangian approach

International Nuclear Information System (INIS)

Hagiwara, T.; Nakazawa, N.

1981-01-01

An effective-Lagrangian approach is summarized to estimate the perturbative effect of heavy-mass particles in the leading-logarithmic approximation: the logarithmic corrections to mass-suppressed amplitudes are given in a concise form. We apply the formalism to a simplified model with two scalar fields where one is heavy and the other is light. We derive an effective Lagrangian by calculating heavy-particle one-loop diagrams. Solving renormalization-group equations derived from the effective Lagrangian by light-particle one-loop corrections, we obtain logarithmic corrections to the mass-suppressed amplitudes. The results are confirmed by explicit two-loop calculation in the full theory, up to order O((1/M 2 )1nM 2 ), where M is a heavy scalar mass. It is found that the boundary condition for solving the renormalization-group equations must be specified by the renormalization at the heavy-particle mass. It must also be emphasized that in an effective-Lagrangian approach minimal subtraction is not a proper method of renormalization. The necessity to adopt the conventional momentum-shell subtraction is stressed. Several applications of this formalism are also mentioned

Isgur-Wise function for heavy-light mesons in the D-dimensional potential model

International Nuclear Information System (INIS)

Roy, Sabyasachi; Choudhury, D K; Hazarika, B J

2012-01-01

We report the results of a wave function for mesons in D space-time dimension developed by considering the quark-antiquark potential of Nambu-Goto strings. With this wave function, we have studied the Isgur-Wise function for heavy-light mesons and its derivatives such as slope and curvature. The dimensional dependence of our results and a comparative study with the results of three-dimensional QCD are also reported.

A light scalar-HLQBS interplay and a HLQBS weak decay test

International Nuclear Information System (INIS)

Kozlov, G.A.

1993-01-01

The interplay between a light scalar boson (Higgs) and a heavy-light quark bound system (HLQBS) in the flavour-changing of the heavy quarks is presented. The estimations of the transition form-factors in the weak leptonic decays of the pseudoscalar HLQBS are proposed. (orig.)

Handbook on Lead-bismuth Eutectic Alloy and Lead Properties, Materials Compatibility, Thermal-hydraulics and Technologies - 2015 Edition

International Nuclear Information System (INIS)

Fazio, Concetta; Sobolev, V.P.; Aerts, A.; Gavrilov, S.; Lambrinou, K.; Schuurmans, P.; Gessi, A.; Agostini, P.; Ciampichetti, A.; Martinelli, L.; Gosse, S.; Balbaud-Celerier, F.; Courouau, J.L.; Terlain, A.; Li, N.; Glasbrenner, H.; Neuhausen, J.; Heinitz, S.; Zanini, L.; Dai, Y.; Jolkkonen, M.; Kurata, Y.; Obara, T.; Thiolliere, N.; Martin-Munoz, F.J.; Heinzel, A.; Weisenburger, A.; Mueller, G.; Schumacher, G.; Jianu, A.; Pacio, J.; Marocco, L.; Stieglitz, R.; Wetzel, T.; Daubner, M.; Litfin, K.; Vogt, J.B.; Proriol-Serre, I.; Gorse, D.; Eckert, S.; Stefani, F.; Buchenau, D.; Wondrak, T.; Hwang, I.S.

2015-01-01

Heavy liquid metals such as lead or lead-bismuth have been proposed and investigated as coolants for fast reactors since the 1950's. More recently, there has been renewed interest worldwide in the use of these materials to support the development of systems for the transmutation of radioactive waste. Heavy liquid metals are also under evaluation as a reactor core coolant and accelerator-driven system neutron spallation source. Several national and international R and D programmes are ongoing for the development of liquid lead-alloy technology and the design of liquid lead-alloy-cooled reactor systems. In 2007, a first edition of the handbook was published to provide deeper insight into the properties and experimental results in relation to lead and lead-bismuth eutectic technology and to establish a common database. This handbook remains a reference in the field and is a valuable tool for designers and researchers with an interest in heavy liquid metals. The 2015 edition includes updated data resulting from various national and international R and D programmes and contains new experimental data to help understand some important phenomena such as liquid metal embrittlement and turbulent heat transfer in a fuel bundle. The handbook provides an overview of liquid lead and lead-bismuth eutectic properties, materials compatibility and testing issues, key aspects of thermal-hydraulics and existing facilities, as well as perspectives for future R and D. (authors)

Association between light absorption measurements of PM2.5 and distance from heavy traffic roads in the Mexico City metropolitan area.

Science.gov (United States)

Cortez-Lugo, Marlene; Escamilla-Núñez, Consuelo; Barraza-Villarreal, Albino; Texcalac-Sangrador, José Luis; Chow, Judith; Watson, John; Hernández-Cadena, Leticia; Romieu, Isabelle

2013-04-01

To study the relationship between light absorption measurements of PM2.5 at various distances from heavy traffic roads and diesel vehicle counts in Mexico City. PM2.5 samples were obtained from June 2003-June 2005 in three MCMA regions. Light absorption (b abs) in a subset of PM2.5 samples was determined. We evaluated the effect of distance and diesel vehicle counts to heavy traffic roads on PM2.5 b abs using generalized estimating equation models. Median PM2.5 b abs measurements significantly decrease as distance from heavy traffic roads increases (proads. Our model predicts that PM2.5 b abs measurements would increase by 20% (CI95% 3-38) as the hourly heavy diesel vehicle count increases by 150 per hour. PM2.5 b abs measurements are significantly associated with distance from motorways and traffic density and therefore can be used to assess human exposure to traffic-related emissions.

Research in heavy-ion nuclear physics

International Nuclear Information System (INIS)

Sanders, S.J.; Prosser, F.W.

1992-01-01

This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the 24 Mg+ 24 Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development

Development of the heavy manipulator vehicle system

International Nuclear Information System (INIS)

Herbst, C.; Paustian, P.; Kruger, W.

1993-01-01

After the severe reactor accident of Tschernobyl in 1986 MaK System started to develop a Heavy Manipulator Vehicle System under contract from German nuclear technology assistance company ''KHG'' (Kerntechnische Hilfsdienst GmbH). The system comprises a remote controlled manipulator vehicle, a mobile mission control stand as well as a transport/service unit. In order to fulfill the high demands of this complex system a couple of new developments had to be started. The paper describes some of these developments and gives an overview about the main features of the Heavy Manipulator Vehicle System (HMV). (author)

FIBER OPTIC LIGHTING SYSTEMS

Directory of Open Access Journals (Sweden)

Munir BATUR

2013-01-01

Full Text Available Recently there have been many important and valuable developments in the communication industry. The huge increase in the sound, data and visual communications has caused a parallel increase in the demand for systems with wider capacity, higher speed and higher quality. Communication systems that use light to transfer data are immensely increased. There have recently many systems in which glass or plastic fiber cables were developed for light wave to be transmitted from a source to a target place. Fiber optic systems, are nowadays widely used in energy transmission control systems, medicine, industry and lighting. The basics of the system is, movement of light from one point to another point in fiber cable with reflections. Fiber optic lighting systems are quite secure than other lighting systems and have flexibility for realizing many different designs. This situation makes fiber optics an alternative for other lighting systems. Fiber optic lighting systems usage is increasing day-by-day in our life. In this article, these systems are discussed in detail.

Experimental concept and design of DarkLight, a search for a heavy photon

International Nuclear Information System (INIS)

Cowan, Ray F.

2013-01-01

This talk gives an overview of the DarkLight experimental concept: a search for a heavy photon A′ in the 10-90 MeV/c 2 mass range. After briefly describing the theoretical motivation, the talk focuses on the experimental concept and design. Topics include operation using a half-megawatt, 100 MeV electron beam at the Jefferson Lab FEL, detector design and performance, and expected backgrounds estimated from beam tests and Monte Carlo simulations

Heavy fragment radioactivity

International Nuclear Information System (INIS)

Silisteanu, I.

1991-06-01

The effect of collective mode excitation in heavy fragment radioactivity (HFR) is explored and discussed in the light of current experimental data. It is found that the coupling and resonance effects in fragment interaction and also the proper angular momentum effects may lead to an important enhancing of the emission process. New useful procedures are proposed for the study of nuclear decay properties. The relations between different decay processes are investigated in detail. We are also trying to understand and explain in a unified way the reaction mechanisms in decay phenomena. (author). 17 refs, 4 figs, 3 tabs

A Corpus-based Stylistic Analysis of Body-Soul and Heaviness-Lightness Metaphors in Kundera's Novel The Unbearable Lightness of Being

Directory of Open Access Journals (Sweden)

Khalid Shakir Hussein

2015-10-01

Full Text Available This paper represents an attempt to conduct a corpus-based stylistic analysis of  two conceptual metaphors in The Unbearable Lightness of Being, which is a novel written by Milan Kundera. Soul-body and lightness-heaviness metaphors are foregrounded as being central themes all through the novel. The way such metaphors are used in the novel indicates an insightful employment of metaphor as a cognitive tool which empowers language users with a capacity of conceptualizing different experiences. The researcher adopts conceptual metaphor theory to produce a sort of conceptual analysis incorporating Leech's semantic componential analysis within the overall analytic procedure. Different techniques are figured out in relation to the creative ways of manipulating the cognitive level of language, such as conceptual switching, conceptual extension, and conceptual fusion. These creative techniques are carefully used in the novel under investigation with different ranges of metaphorical creativity. Conceptual switching might be simple but very active in deviating from the conventional conceptual system. Conceptual extension marks certain minute elaborations conventional metaphors undergo extending the limits of cognitive conceptualization. As for conceptual fusion, it proves to be interestingly powerful in producing certain aggregations of metaphorical mappings. Keywords: Conceptual Metaphor Theory, Metaphorical Creativity, Metaphorical Mappings, Corpus Stylistics

Corrector/quadrupole/sextupole power leads for the Relativistic Heavy Ion Collider at Brookhaven National Laboratory

International Nuclear Information System (INIS)

Shutt, R.; Hornik, K.; Rehak, M.

1993-01-01

In RHIC (Relativistic Heavy Ion Collider), there are 492 CQS (Corrector/Quadrupole/Sextupole) assemblies which require leads to carry the current from the power supply to the magnet. The lead assemblies will contain these leads along with instrumentation voltage taps and current carrying wires that are used only for magnet warm-up. These lead assemblies are analyzed for two cooling schemes: (1) gas flow through the lead tube and (2) heat sinking the lead tube along a 40--70 K heat shield (without gas flow). The analysis was extended to include the modeling of the cold and warm ends and effects of superinsulation shielding the lead assembly against radiation (including heat conduction due to residual gas pressure in the surrounding vacuum). Extensive parametric studies of heat exchange areas, specific copper properties, length of the lead, etc. are also included in the analysis

Thermal performance of heavy-weight and light-weight steel frame construction approaches in the central Pretoria climate

CSIR Research Space (South Africa)

Kumirai, T

2013-01-01

Full Text Available -1 Journal for New Generation Sciences Thermal performance of heavy-weight and light-weight steel frame construction approaches in the central Pretoria climate T Kumirai and DCU Conradie Built Environment, Council for Scientific and Industrial...

Neutron production in lead targets by high-energy light-mass heavy ions

International Nuclear Information System (INIS)

Daniehl', A.V.; Lyapin, V.S.; Tsvetkov, I.O.

1992-01-01

The characteristics of the time-of-flight spectrometer and the double different distributions of neutrons and secondary charged particles produced by 2 GeV protons and 1 GeVXA d,α, 6 Li and 12 C ions bombarding lead targets are described. Experimental data are compared with the results of calculations by codes SITHA. 17 refs.; 10 figs.; 1 tab

Evolution of nuclear shape in the light radon isotopes

CERN Multimedia

Reiter, P; Blazhev, A A; Kruecken, R; Rahkila, P J; Grahn, T; Wadsworth, R; Gernhaeuser, R A; Bree, N C F; Habs, D; Jenkins, D G; Huyse, M L

2008-01-01

We propose to carry out Coulomb excitation of post-accelerated beams of $^{202,204}$ Rn from the REX-ISOLDE facility. The aim of this study is to expand our understanding of nuclear shape coexistence, which has been increasingly well-established in the light mercury and lead nuclei to these very heavy nuclei. Such an extension will provide stringent tests of nuclear models of collectivity and shape coexistence in a previously-inaccessible heavy mass region. REX- ISOLDE is the only facility worldwide at the present time which can provide accelerated beams of such heavy radioactive nuclei.

Unknown risk: co-exposure to lead and other heavy metals among children living in small-scale mining communities in Zamfara State, Nigeria.

Science.gov (United States)

Bartrem, Casey; Tirima, Simba; von Lindern, Ian; von Braun, Margrit; Worrell, Mary Claire; Mohammad Anka, Shehu; Abdullahi, Aishat; Moller, Gregory

2014-08-01

The lead poisoning crisis in Zamfara State, Northern Nigeria has been called the worst such case in modern history and it presents unique challenges for risk assessment and management of co-exposure to multiple heavy metals. More than 400 children have died in Zamfara as a result of ongoing lead intoxication since early in 2010. A review of the common toxic endpoints of the major heavy metals advances analysis of co-exposures and their common pathologies. Environmental contamination in Bagega village, examined by X-ray fluorescence of soils, includes lead, mercury, cadmium, arsenic and manganese. Co-exposure risk is explored by scoring common toxic endpoints and hazard indices to calculate a common pathology hazard risk ranking of Pb > As > Hg > Cd > Mn. Zamfara presents an extreme picture of both lead and multiple heavy metal mortality and morbidity, but similar situations have become increasingly prevalent worldwide.

High-Performance Red-Light Photodetector Based on Lead-Free Bismuth Halide Perovskite Film.

Science.gov (United States)

Tong, Xiao-Wei; Kong, Wei-Yu; Wang, You-Yi; Zhu, Jin-Miao; Luo, Lin-Bao; Wang, Zheng-Hua

2017-06-07

In this study, we developed a sensitive red-light photodetector (RLPD) based on CsBi 3 I 10 perovskite thin film. This inorganic, lead-free perovskite was fabricated by a simple spin-coating method. Device analysis reveals that the as-assembled RLPD was very sensitive to 650 nm light, with an on/off ratio as high as 10 5 . The responsivity and specific detectivity of the device were estimated to be 21.8 A/W and 1.93 × 10 13 Jones, respectively, which are much better than those of other lead halide perovskite devices. In addition, the device shows a fast response (rise time: 0.33 ms; fall time: 0.38 ms) and a high external quantum efficiency (4.13 × 10 3 %). It is also revealed that the RLPD has a very good device stability even after storage for 3 months under ambient conditions. In summary, we suggest that the CsBi 3 I 10 perovskite photodetector developed in this study may have potential applications in future optoelectronic systems.

Delay in polling systems in heavy traffic

Science.gov (United States)

van der Mei, Robert D.

1998-10-01

We study the delay in asymmetric cyclic polling systems with general mixtures of gated and exhaustive service, with generally distributed service times and switch-over times, in heavy traffic. We obtain closed-form expressions for all moments of the delay incurred at each of the queues. The expressions are strikingly simple and can even be expressed as finite products of known factors. The results provide new insights into the heavy-traffic behavior of polling systems.

Fragment formation in GeV-energy proton and light heavy-ion induced reactions

International Nuclear Information System (INIS)

Murakami, T.; Haga, M.; Haseno, M.

2002-01-01

We have investigated similarities and differences among the fragment formation processes in GeV-energy light-ion and light heavy-ion induced reactions. We have newly measured inclusive and exclusive energy spectra of intermediate mass fragments (3 ≤ Z ≤ 30; IMFs) for 8-GeV 16 O and 20 Ne and 12-GeV 20 Ne induced target multifragmentations (TMFs) in order to compare them with those previously measured for 8- and 12-GeV proton induced TMFs. We fond noticeable difference in their spectrum shapes and magnitudes but all of them clearly indicate the existence of sideward-peaked components, indicating fragment formations are mainly dictated not by a incident energy per nucleon but by a total energy of the projectile. (author)

Measurement of the plastic scintillator response to heavy ions, between 0 to 30 MeV/N

International Nuclear Information System (INIS)

Dorion, I.

1984-01-01

The light produced in a plastic scintillator depends on particle nature and energy. Theoretical models predict a linear behavior of the light output response for high energy heavy ions. An experimental set-up was realised in order to perform the integral and, in some case, the differential measurement of the light yield in a plastic scintillator (NE102) stopping 6 Li, 12 C, 16 O, 20 Ne, 40 Ar ions given by SARA, with particle incident energy from 3 to 30 MeV per nucleon. The plastic resolution was also measured. The data analysis leads to experimental results which are in good agreement with the predictions. Taking into account resolution value, the use of plastic scintillator in detection system allows in some case, particle identification [fr

A lattice QCD determination of potentials between pairs of static-light mesons

International Nuclear Information System (INIS)

Hetzenegger, Martin

2011-01-01

Potentials between pairs of static-light mesons are interesting in a sense that they give insights in the nature of strong interactions from first principles for multiquark systems. For large heavy quark masses, e.g., the spectra of heavy-light mesons are determined by excitations of the light quark and gluonic degrees of freedom. In particular, the vector-pseudoscalar splitting vanishes and a static-light meson can be interpreted as either a B, a B * , a D or a D * heavy-light meson. Calculating potentials between two static-light mesons also enables investigations of possible bound tetraquark states or for particles that are close to the meson-antimeson threshold, such as the X(3872) or the Z + (4430).

Role of passive valves & devices in poison injection system of advanced heavy water reactor

International Nuclear Information System (INIS)

Sapra, M.K.; Kundu, S.; Vijayan, P.K.; Vaze, K.K.; Sinha, R.K.

2014-01-01

The Advanced Heavy Water Reactor (AHWR) is a 300 MWe pressure tube type boiling light water (H 2 O) cooled, heavy water (D 2 O) moderated reactor. The reactor design is based on well-proven water reactor technologies and incorporates a number of passive safety features such as natural circulation core cooling; direct in-bundle injection of light water coolant during a Loss of Coolant Accident (LOCA) from Advanced Accumulators and Gravity Driven Water Pool by passive means; Passive Decay Heat Removal using Isolation Condensers, Passive Containment Cooling System and Passive Containment Isolation System. In addition to above, there is another passive safety system named as Passive Poison Injection System (PPIS) which is capable of shutting down the reactor for a prolonged time. It is an additional safety system in AHWR to fulfill the shutdown function in the event of failure of wired shutdown systems i.e. primary and secondary shut down systems of the reactor. When demanded, PPIS injects the liquid poison into the moderator by passive means using passive valves and devices. On increase of main heat transport (MHT) system pressure beyond a predetermined value, a set of rupture disks burst, which in-turn actuate the passive valve. The opening of passive valve initiates inrush of high pressure helium gas into poison tanks to push the poison into the moderator system, thereby shutting down the reactor. This paper primarily deals with design and development of Passive Poison Injection System (PPIS) and its passive valves & devices. Recently, a prototype DN 65 size Poison Injection Passive Valve (PIPV) has been developed for AHWR usage and tested rigorously under simulated conditions. The paper will highlight the role of passive valves & devices in PPIS of AHWR. The design concept and test results of passive valves along with rupture disk performance will also be covered. (author)

Water chemistry features of advanced heavy water reactor

International Nuclear Information System (INIS)

Sriram, Jayasree; Vijayan, K.; Kain, Vivekanad; Velmurugan, S.

2015-01-01

Advanced Heavy Water Reactor (AHWR) being designed in India proposes to use Plutonium and Thorium as fuel. The objective is to extract energy from the uranium-233 formed from Thorium. It is a heavy water moderated and light water cooled tube type boiling water reactor. It is a heavy water moderated and light water cooled tube type boiling water reactor. It is a natural circulation reactor. Thus, it has got several advanced passive safety features built into the system. The various water coolant systems are listed below. i) Main Heat transport System ii) Feed water system iii) Condenser cooling system iv) Process water system and safety systems. As it is a tube type reactor, the radiolysis control differs from the normal boiling water reactor. The coolant enters the bottom of the coolant channel, boiling takes place and then the entire steam water mixture exits the core through the long tail pipes and reaches the moisture separator. Thus, there is a need to devise methods to protect the tail pipes from oxidizing water chemistry condition. Similarly, the moderator heavy water coolant chemistry differs from that of moderator system chemistry of PHWR. The reactivity worth per ppm of gadolinium and boron are low in comparison to PHWR. As a result, much higher concentration of neutron poison has to be added for planned shutdown, start up and for actuating SDS-2. The addition of higher concentration of neutron poison result in higher radiolytic production of deuterium and oxygen. Their recombination back to heavy water has to take into account the higher production of these gases. This paper also discusses the chemistry features of safety systems of AHWR. In addition, the presentation will cover the chemistry monitoring methodology to be implemented in AHWR. (author)

Light and heavy touch reduces postural sway and modifies axial tone in Parkinson’s disease

Science.gov (United States)

Franzén, Erika; Paquette, Caroline; Gurfinkel, Victor; Horak, Fay

2014-01-01

Background Light touch with a stable object reduces postural sway by increasing axial postural tone in healthy subjects. However, it is unknown whether subjects with Parkinson’s disease (PD), who have more postural sway and higher axial postural tone than healthy subjects, can benefit from haptic touch. Objective To investigate the effect of light and heavy touch on postural stability and hip tone in subjects with PD. Methods Fourteen subjects with mid-stage PD, and 14 healthy control subjects were evaluated during quiet standing with eyes closed with their arms: 1) crossed, 2) lightly touching a fixed rigid bar in front of them and 3) firmly gripping the bar. Postural sway was measured with a forceplate and axial hip tone was quantified using a unique device that measures the resistance of the hips to yaw rotation while maintaining active stance. Results Subjects with PD significantly decreased their postural sway with light or heavy touch (ptouch, hip tone was larger in PD subjects. With touch, however, tone values were similar in both groups. This change in hip tone with touch was highly correlated with the initial amount of tone (PD: r=− 0.72 to −0.95 and controls: r=−0.74 to−0.85). Conclusions We showed, for the first time, that subjects with PD benefit from touch similarly to control subjects and that despite higher axial postural tone, PD subjects are able to modulate their tone with touch. Future studies should investigate the complex relationship between touch and postural tone. PMID:22415944

Universality classes far from equilibrium. From heavy-ion collisions to superfluid Bose systems

International Nuclear Information System (INIS)

Boguslavski, Kirill

2016-01-01

Quantum many-body systems far from equilibrium can approach a nonthermal fixed point during their real-time evolution. One example is scalar field theory, which occurs in models of cosmological inflation, and similar examples are found for non-Abelian plasmas relevant for heavy-ion collisions and for ultracold Bose gases. Investigating nonthermal fixed points of different microscopic theories, we present two novel universality classes that provide links between these systems. One of them involves nonrelativistic, N-component relativistic and expanding scalar systems. It occurs in the deep infrared regime of very high occupancies and is governed by a self-similar evolution. Its nonequilibrium dynamics leads to the formation of a Bose-Einstein condensate. The scaling properties of this region can be described by a vertex-resummed kinetic theory that is based on a systematic large-N expansion at next-to-leading order. The other novel universality class encompasses scalar field theories and non-Abelian plasmas in a longitudinally expanding background and corresponds to an early dynamical stage of heavy-ion collisions in the high-energy limit. We show that these systems share the same self-similar scaling properties for a wide range of momenta in a limit where particles are weakly coupled but their occupancy is high. Both universality classes are found in separate momentum regions in a longitudinally expanding N-component scalar field theory. We argue that the important role of the infrared dynamics ensures that key features of our results for scalar and gauge theories cannot be reproduced consistently in conventional kinetic theory frameworks. Moreover, the observed universality connects different physics disciplines from heavy-ion collisions to ultracold atoms, making a remarkable link between the world's hottest and coldest matter.

Universality classes far from equilibrium. From heavy-ion collisions to superfluid Bose systems

Energy Technology Data Exchange (ETDEWEB)

Boguslavski, Kirill

2016-07-27

Quantum many-body systems far from equilibrium can approach a nonthermal fixed point during their real-time evolution. One example is scalar field theory, which occurs in models of cosmological inflation, and similar examples are found for non-Abelian plasmas relevant for heavy-ion collisions and for ultracold Bose gases. Investigating nonthermal fixed points of different microscopic theories, we present two novel universality classes that provide links between these systems. One of them involves nonrelativistic, N-component relativistic and expanding scalar systems. It occurs in the deep infrared regime of very high occupancies and is governed by a self-similar evolution. Its nonequilibrium dynamics leads to the formation of a Bose-Einstein condensate. The scaling properties of this region can be described by a vertex-resummed kinetic theory that is based on a systematic large-N expansion at next-to-leading order. The other novel universality class encompasses scalar field theories and non-Abelian plasmas in a longitudinally expanding background and corresponds to an early dynamical stage of heavy-ion collisions in the high-energy limit. We show that these systems share the same self-similar scaling properties for a wide range of momenta in a limit where particles are weakly coupled but their occupancy is high. Both universality classes are found in separate momentum regions in a longitudinally expanding N-component scalar field theory. We argue that the important role of the infrared dynamics ensures that key features of our results for scalar and gauge theories cannot be reproduced consistently in conventional kinetic theory frameworks. Moreover, the observed universality connects different physics disciplines from heavy-ion collisions to ultracold atoms, making a remarkable link between the world's hottest and coldest matter.

Vibroacoustic Modeling of Mechanically Coupled Structures: Artificial Spring Technique Applied to Light and Heavy Mediums

Directory of Open Access Journals (Sweden)

L. Cheng

1996-01-01

Full Text Available This article deals with the modeling of vibrating structures immersed in both light and heavy fluids, and possible applications to noise control problems and industrial vessels containing fluids. A theoretical approach, using artificial spring systems to characterize the mechanical coupling between substructures, is extended to include fluid loading. A structure consisting of a plate-ended cylindrical shell and its enclosed acoustic cavity is analyzed. After a brief description of the proposed technique, a number of numerical results are presented. The analysis addresses the following specific issues: the coupling between the plate and the shell; the coupling between the structure and the enclosure; the possibilities and difficulties regarding internal soundproofing through modifications of the joint connections; and the effects of fluid loading on the vibration of the structure.

[Mixed valent and heavy ferimons and related systems

International Nuclear Information System (INIS)

Schlottmann, P.

1991-01-01

The main objective of the project is to gain a better understanding of highly correlated fermion systems. High correlations appear in a variety of solid state phenomena: mixed-valence and heavy-fermions or Kondo systems, superfluid and normal He 3 , high-temperature superconductors, magnetism in low dimensions, quantum Hall effect, spin-fluctuations in transition metals, giant magnetic moments, tunneling of an atom interacting with a degenerate electron gas, quantum dissipative systems, organic superconductors, etc. The primary focus of the work is on valence mixing and heavy fermions, but elated highly correlated systems are also studied. In this paper a brief summary of the achievements grouped under four headings, namely (1) heavy fermions-mixed valence-Kondo, (2) magnetism in low dimensions, (3) narrow band phenomena/Hubbard model and (4) collaborations with experimentalists

Dynamical Flavor Hierarchy and Heavy Top

CERN Document Server

Dvali, Gia; Dvali, Gia; Kakushadze, Zurab

1998-01-01

In the Standard Model one of the generations is much heavier than the other two. We propose a simple mechanism where all three generations are treated on the equal footing to begin with, and one heavy and two light families emerge from supersymmetric strong dynamics. The Yukawa mass matrix is identified with vevs of the meson fields of some additional gauge theory. It is then forced to have rank one (in the leading order) by non-perturbative superpotential.

Natural light illumination system.

Science.gov (United States)

Whang, Allen Jong-Woei; Chen, Yi-Yung; Yang, Shu-Hua; Pan, Po-Hsuan; Chou, Kao-Hsu; Lee, Yu-Chi; Lee, Zong-Yi; Chen, Chi-An; Chen, Cheng-Nan

2010-12-10

In recent years, green energy has undergone a lot of development and has been the subject of many applications. Many research studies have focused on illumination with sunlight as a means of saving energy and creating healthy lighting. Natural light illumination systems have collecting, transmitting, and lighting elements. Today, most daylight collectors use dynamic concentrators; these include Sun tracking systems. However, this design is too expensive to be cost effective. To create a low-cost collector that can be easily installed on a large building, we have designed a static concentrator, which is prismatic and cascadable, to collect sunlight for indoor illumination. The transmission component uses a large number of optical fibers. Because optical fibers are expensive, this means that most of the cost for the system will be related to transmission. In this paper, we also use a prismatic structure to design an optical coupler for coupling n to 1. With the n-to-1 coupler, the number of optical fibers necessary can be greatly reduced. Although this new natural light illumination system can effectively guide collected sunlight and send it to the basement or to other indoor places for healthy lighting, previously there has been no way to manage the collected sunlight when lighting was not desired. To solve this problem, we have designed an optical switch and a beam splitter to control and separate the transmitted light. When replacing traditional sources, the lighting should have similar characteristics, such as intensity distribution and geometric parameters, to those of traditional artificial sources. We have designed, simulated, and optimized an illumination lightpipe with a dot pattern to redistribute the collected sunlight from the natural light illumination system such that it equals the qualities of a traditional lighting system. We also provide an active lighting module that provides lighting from the natural light illumination system or LED auxiliary

Survival of high pT light and heavy flavors in a dense medium

International Nuclear Information System (INIS)

Kopeliovich, B. Z.

2011-01-01

This talk presents an attempt at a critical overview of the current status of modeling for high-p T processes in nuclei. In particular, it includes discussion of the space-time development of hadronization of highly virtual light and heavy partons, and the related time scales; the role of early production and subsequent attenuation of pre-hadrons in a dense medium. We identify several challenging problems within the current interpretation of high-p T processes and propose solutions for some of them.

New heavy-lift system under construction

Energy Technology Data Exchange (ETDEWEB)

2009-07-01

Heavy-lift availability is at a premium, and the market is eager for alternatives to meet the demand. An alternative heavy-lift solution from SeaMetric - which has two multi-purpose heavy-lift vessels under construction in China - will be available in the first quarter of 2011. The TML system is based on buoyancy and ballast tanks, with four lifting arms mounted on two identical vessels, each vessel measuring 140 x 40 x 10.75 metres. To perform a lift, one TML with lifting arms is positioned on each side of the object. Using seawater pumps, lift force is created by de ballasting the buoyancy tanks and at the same time ballasting the ballast tanks. (AG). tab., ills

Modeling of photoluminescence in laser-based lighting systems

Science.gov (United States)

Chatzizyrli, Elisavet; Tinne, Nadine; Lachmayer, Roland; Neumann, Jörg; Kracht, Dietmar

2017-12-01

The development of laser-based lighting systems has been the latest step towards a revolution in illumination technology brought about by solid-state lighting. Laser-activated remote phosphor systems produce white light sources with significantly higher luminance than LEDs. The weak point of such systems is often considered to be the conversion element. The high-intensity exciting laser beam in combination with the limited thermal conductivity of ceramic phosphor materials leads to thermal quenching, the phenomenon in which the emission efficiency decreases as temperature rises. For this reason, the aim of the presented study is the modeling of remote phosphor systems in order to investigate their thermal limitations and to calculate the parameters for optimizing the efficiency of such systems. The common approach to simulate remote phosphor systems utilizes a combination of different tools such as ray tracing algorithms and wave optics tools for describing the incident and converted light, whereas the modeling of the conversion process itself, i.e. photoluminescence, in most cases is circumvented by using the absorption and emission spectra of the phosphor material. In this study, we describe the processes involved in luminescence quantum-mechanically using the single-configurational-coordinate diagram as well as the Franck-Condon principle and propose a simulation model that incorporates the temperature dependence of these processes. Following an increasing awareness of climate change and environmental issues, the development of ecologically friendly lighting systems featuring low power consumption and high luminous efficiency is imperative more than ever. The better understanding of laser-based lighting systems is an important step towards that aim as they may improve on LEDs in the near future.

Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

Energy Technology Data Exchange (ETDEWEB)

Hoelzel, Christina S., E-mail: Christina.Hoelzel@wzw.tum.de [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mueller, Christa [Institute for Agroecology, Organic Farming and Soil Protection, Bavarian State Research Center for Agriculture (LfL), Lange Point 12, 85354 Freising (Germany); Harms, Katrin S. [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany); Mikolajewski, Sabine [Department for Quality Assurance and Analytics, Bavarian State Research Center for Agriculture (LfL), Lange Point 4, 85354 Freising (Germany); Schaefer, Stefanie; Schwaiger, Karin; Bauer, Johann [Chair of Animal Hygiene, Technische Universitaet Muenchen, Weihenstephaner Berg 3, 85354 Freising (Germany)

2012-02-15

Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08-5.30 mg cadmium, 1.1-32.0 mg chrome, 22.4-3387.6 mg copper, <2.0-26.7 mg lead, <0.01-0.11 mg mercury, 3.1-97.3 mg nickel and 93.0-8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against {beta}-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against {beta}-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

A lattice QCD determination of potentials between pairs of static-light mesons

Energy Technology Data Exchange (ETDEWEB)

Hetzenegger, Martin

2011-07-04

Potentials between pairs of static-light mesons are interesting in a sense that they give insights in the nature of strong interactions from first principles for multiquark systems. For large heavy quark masses, e.g., the spectra of heavy-light mesons are determined by excitations of the light quark and gluonic degrees of freedom. In particular, the vector-pseudoscalar splitting vanishes and a static-light meson can be interpreted as either a B, a B{sup *}, a D or a D{sup *} heavy-light meson. Calculating potentials between two static-light mesons also enables investigations of possible bound tetraquark states or for particles that are close to the meson-antimeson threshold, such as the X(3872) or the Z{sup +}(4430).

Heavy water upgrader of 'Fugen'

International Nuclear Information System (INIS)

Matsushita, Tadashi; Sasaki, Shigeo

1980-01-01

The nuclear power station of the advanced thermal prototype reactor ''Fugen'' has continued the smooth operation since it started the fullscale operation in March, 1979. Fugen is the first heavy water-moderated, boiling light water-cooled reactor in Japan, and its outstanding feature is the use of heavy water as the moderator. The quantity of heavy water retained in Fugen is about 140 m 3 , and the concentration is 99.8 wt.%. This heavy water had been made is USA, and was imported from F.R. of Germany where it had been used. Heavy water is an internationally regulated material, and it is very expensive and hard to purchase. Therefore in order to prevent the deterioration of heavy water and to avoid its loss as far as possible, the management of the quantity and the control of the water quality have been carried out carefully and strictly. The generation of deteriorated heavy water occurs from the exchange of ion exchange resin for poison removal and purification. The heavy water upgrader reconcentrates the deteriorated heavy water of high concentration and returns to the heavy water system, and it was installed for the purpose of reducing the purchase of supplementary heavy water. The outline of the heavy water upgrader, its construction, the performance test and the operation are described. (Kako, I.)

Fusion of light ion systems at energies near and below the Coulomb barrier

International Nuclear Information System (INIS)

Arnould, M.; Howard, W.M.; Cusson, R.Y.

1978-01-01

Experimental fusion cross sections for light ion systems at energies below the Coulomb barrier become available in greater and greater number, and provide a stringent test of the macroscopic and microscopic physics involved in models of heavy-ion reactions. Measurements and predictions of the fusion cross sections for 12 C + 12 C, 12 C + 16 O and 16 O + 16 O are also of major importance in astrophysics. (orig.) [de

Lighting Control System for Premises with Display Screen Equipment

Science.gov (United States)

Kudryashov, A. V.

2017-11-01

The use of Display Screen Equipment (DSE) at enterprises allows one to increase the productivity and safety of production, minimize the number of personnel and leads to the simplification of the work of specialists, but on the other side, changes usual working conditions. If the personnel works with displays, visual fatigue develops more quickly which contributes to the emergence of nervous tension, stress and possible erroneous actions. Low interest of the lighting control system developers towards the rooms with displays is dictated by special requirements for coverage by sanitary and hygienic standards (limiting excess workplace illumination). We decided to create a combined lighting system which works considering daylight illumination and artificial light sources. The brightness adjustment of the LED lamps is carried out according to the DALI protocol, adjustment of the natural illumination by means of smart glasses. The technical requirements for a lighting control system, the structural-functional scheme and the algorithm for controlling the operation of the system have been developed. The elements of control units, sensors and actuators have been selected.

Transport of heavy ions through matter within ion optical systems

International Nuclear Information System (INIS)

Schwab, T.

1991-04-01

In this thesis for the first time higher-order ion-optical calculations were connected with the whole phase-space changes of the heavy ions in passing through matter. With the developed programs and the newly proposed analytical methods atomic and nuclear interactions of the heavy ions within ion optical systems can be described realistically. The results of this thesis were applied to the conception of the fragment separator (FRS) and to the planning and preparation of experiments at the new GSI accelerator facility. Especially for the description of the ion-optical combination of FRS and the storage ring ESR the developed programs and methods proved to be necessary. A part of the applied theories on the atomic stopping could be confirmed in the framework of this thesis in an experiment with the high-resolving spectrometer SPEC at GANIL. The method of the isotopically pure separation of projectile fragments by means of magnetic analysis and the electronic energy loss could be also experimentally successfully tested at several energies (60-400 MeV/u). Furthermore in this thesis also application-related problems regarding a tumor therapy with heavy ions were solved. A concept for a medical separator (BMS) was developed, which separates light diagnosis beams isotopically purely and beyond improves the energy sharpness by means of an especially shaped (monoenergetic) stopper so that an in-situ range determination is possible with an accuracy of about one millimeter. (orig./HSI) [de

Neutral B Meson Mixing and Heavy-light Decay Constants from Quenched Lattice QCD

CERN Document Server

Lellouch, Laurent; Lellouch, Laurent

1999-01-01

We present high-statistics results for neutral B-meson mixing and heavy-light-meson leptonic decays in the quenched approximation from tadpole-improved clover actions at beta =6.0 and beta =6.2. We consider quantities such as B(B/sub d/(s)), f(D/sub d/(s)), f(B/sub d /(s)) and the full Delta B=2 matrix elements as well as the corresponding SU(3)-breaking ratios. These quantities are important for determining the CKM matrix element ¦V/sub td/¦. (5 refs).

Dynamic deformation theory of spherical and deformed light and heavy nuclei with A = 12-240

International Nuclear Information System (INIS)

Kumar, Krishna.

1979-01-01

Deformation dependent wave functions are calculated for different types of even-even nuclei (spherical, transitional, deformed; light, medium, heavy) without any fitting parameters. These wave functions are employed for the energies, B(E2)'s, quadrupole and magnetic moments of selected nuclei with A = 12-240 (with special emphasis on 56 Fe, 154 Gd), and for neutron cross sections of 148 Sm, 152 Sm

Quarkonia and heavy-light mesons in a covariant quark model

Directory of Open Access Journals (Sweden)

Leitão Sofia

2016-01-01

Full Text Available Preliminary calculations using the Covariant Spectator Theory (CST employed a scalar linear confining interaction and an additional constant vector potential to compute the mesonic mass spectra. In this work we generalize the confining interaction to include more general structures, in particular a vector and also a pseudoscalar part, as suggested by a recent study [1]. A one-gluon-exchange kernel is also implemented to describe the short-range part of the interaction. We solve the simplest CST approximation to the complete Bethe-Salpeter equation, the one-channel spectator equation, using a numerical technique that eliminates all singularities from the kernel. The parameters of the model are determined through a fit to the experimental pseudoscalar meson spectra, with a good agreement for both quarkonia and heavy-light states.

Leaching Properties of Naturally Occurring Heavy Metals from Soils

Science.gov (United States)

Zhang, M.; Hoshino, M.; Yoshikawa, M.; Hara, J.; Sugita, H.

2014-12-01

The major threats to human health from heavy metals are associated with exposure to arsenic, lead, cadmium, chromium, mercury, as well as some other elements. The effects of such heavy metals on human health have been extensively studied and reviewed by international organizations such as WHO. Due to their toxicity, heavy metal contaminations have been regulated by national environmental standards in many countries, and/or laws such as the Soil Contamination Countermeasures Act in Japan. Leaching of naturally occurring heavy metals from the soils, especially those around abandoned metal mines into surrounding water systems, either groundwater or surface water systems, is one of the major pathways of exposure. Therefore, understanding the leaching properties of toxic heavy metals from naturally polluted soils is of fundamentally importance for effectively managing abandoned metal mines, excavated rocks discharged from infrastructure constructions such as tunneling, and/or selecting a pertinent countermeasure against pollution when it is necessary. In this study, soil samples taken from the surroundings of abandoned metal mines in different regions in Japan were collected and analyzed. The samples contained multiple heavy metals such as lead, arsenic and chromium. Standard leaching test and sequential leaching test considering different forms of contaminants, such as trivalent and pentavalent arsenics, and trivalent and hexavalent chromiums, together with standard test for evaluating total concentration, X-ray Fluorescence Analysis (XRF), X-ray diffraction analysis (XRD) and Cation Exchange Capacity (CEC) tests were performed. In addition, sequential leaching tests were performed to evaluate long-term leaching properties of lead from representative samples. This presentation introduces the details of the above experimental study, discusses the relationships among leaching properties and chemical and mineral compositions, indicates the difficulties associated with

Towards New Ambient Light Systems: a Close Look at Existing Encodings of Ambient Light Systems

Directory of Open Access Journals (Sweden)

Andrii Matviienko

2015-10-01

Full Text Available Ambient systems provide information in the periphery of a user’s attention. Their aim is to present information as unobtrusively as possible to avoid interrupting primary tasks (e.g. writing or reading. In recent years, light has been used to create ambient systems to display information. Examples of ambient light systems range from simple notification systems such as displaying messages or calendar event reminders, to more complex systems such as focusing on conveying information regarding health activity tracking. However, for ambient light systems, there is a broad design space that lacks guidelines on when to make use of light displays and how to design them. In this paper we provide a systematic overview of existing ambient light systems over four identified information classes derived from 72 existing ambient light systems. The most prominent encoding parameters among the surveyed ambient light systems are color, brightness, and their combination. By analyzing existing ambient light systems, we provide a first step towards developing guidelines for designing future ambient light systems.

Heavy quark masses

Science.gov (United States)

Testa, Massimo

1990-01-01

In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

Towards next-to-leading order corrections to the heavy quark potential in the effective string theory

Directory of Open Access Journals (Sweden)

Hwang Sungmin

2017-01-01

Full Text Available We present our calculation of the non-relativistic corrections to the heavy quark-antiquark potential up to leading and next-to-leading order (NLO via the effective string theory (EST. Full systematics of effective field theory (EFT are discussed in order for including the NLO contribution that arises in the EST. We also show how the number of dimensionful parameters arising from the EST are reduced by the constraints between the Wilson coeffcients from non-relativistic EFTs for QCD.

Determination of allergen specificity by heavy chains in grass pollen allergen-specific IgE antibodies.

Science.gov (United States)

Gadermaier, Elisabeth; Flicker, Sabine; Lupinek, Christian; Steinberger, Peter; Valenta, Rudolf

2013-04-01

Affinity and clonality of allergen-specific IgE antibodies are important determinants for the magnitude of IgE-mediated allergic inflammation. We sought to analyze the contribution of heavy and light chains of human allergen-specific IgE antibodies for allergen specificity and to test whether promiscuous pairing of heavy and light chains with different allergen specificity allows binding and might affect affinity. Ten IgE Fabs specific for 3 non-cross-reactive major timothy grass pollen allergens (Phl p 1, Phl p 2, and Phl p 5) obtained by means of combinatorial cloning from patients with grass pollen allergy were used to construct stable recombinant single chain variable fragments (ScFvs) representing the original Fabs and shuffled ScFvs in which heavy chains were recombined with light chains from IgE Fabs with specificity for other allergens by using the pCANTAB 5 E expression system. Possible ancestor genes for the heavy chain and light chain variable region-encoding genes were determined by using sequence comparison with the ImMunoGeneTics database, and their chromosomal locations were determined. Recombinant ScFvs were tested for allergen specificity and epitope recognition by means of direct and sandwich ELISA, and affinity by using surface plasmon resonance experiments. The shuffling experiments demonstrate that promiscuous pairing of heavy and light chains is possible and maintains allergen specificity, which is mainly determined by the heavy chains. ScFvs consisting of different heavy and light chains exhibited different affinities and even epitope specificity for the corresponding allergen. Our results indicate that allergen specificity of allergen-specific IgE is mainly determined by the heavy chains. Different heavy and light chain pairings in allergen-specific IgE antibodies affect affinity and epitope specificity and thus might influence clinical reactivity to allergens. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by

Probing QCD critical fluctuations from light nuclei production in relativistic heavy-ion collisions

Directory of Open Access Journals (Sweden)

Kai-Jia Sun

2017-11-01

Full Text Available Based on the coalescence model for light nuclei production, we show that the yield ratio Op-d-t=NH3Np/Nd2 of p, d, and 3H in heavy-ion collisions is sensitive to the neutron relative density fluctuation Δn=〈(δn2〉/〈n〉2 at kinetic freeze-out. From recent experimental data in central Pb+Pb collisions at sNN=6.3 GeV, 7.6 GeV, 8.8 GeV, 12.3 GeV and 17.3 GeV measured by the NA49 Collaboration at the CERN Super Proton Synchrotron (SPS, we find a possible non-monotonic behavior of Δn as a function of the collision energy with a peak at sNN=8.8 GeV, indicating that the density fluctuations become the largest in collisions at this energy. With the known chemical freeze-out conditions determined from the statistical model fit to experimental data, we obtain a chemical freeze-out temperature of ∼144 MeV and baryon chemical potential of ∼385 MeV at this collision energy, which are close to the critical endpoint in the QCD phase diagram predicted by various theoretical studies. Our results thus suggest the potential usefulness of the yield ratio of light nuclei in relativistic heavy-ion collisions as a direct probe of the large density fluctuations associated with the QCD critical phenomena.

Mass and charge distribution in heavy-ion collisions

International Nuclear Information System (INIS)

Beck, F.; Dworzecka, M.; Feldmeier, H.

1978-01-01

A statistical model based on the independent particle picture is used to calculate mass and charge distributions in deep inelastic heavy-ion collisions. Different assumptions on volume and charge equilibrations are compared with measured variances of charge distributions. One combination of assumptions is clearly favoured by experiment, and gives a reasonable description of the variance versus energy loss curves up to energy losses of about 200 MeV in the heavy systems Kr+Ho and Xe+Bi, and up to about 60 MeV for the light system Ar+Ca [af

Smart brake light system would provide more information to drivers

OpenAIRE

Trulove, Susan

2008-01-01

You are driving in heavy traffic. The brake lights on the car in front of you come on. Is the car slowing or is it going to stop? It slows to 25 mph and the lights go off. You drop back. The car in front of you stops suddenly! You stop just in time. The car behind you collects your rear bumper.

Handbook on lead-bismuth eutectic alloy and lead properties, materials compatibility, thermal-hydraulics and technologies

International Nuclear Information System (INIS)

2007-01-01

As part of the development of advanced nuclear systems, including accelerator-driven systems (ADS) proposed for high-level radioactive waste transmutation and generation IV reactors, heavy liquid metals such as lead (Pb) or lead-bismuth eutectic (LBE) are under evaluation as reactor core coolant and ADS neutron target material. Heavy liquid metals are also being envisaged as target materials for high-power neutron spallation sources. The objective of this handbook is to collate and publish properties and experimental results on Pb and LBE in a consistent format in order to provide designers with a single source of qualified properties and data and to guide subsequent development efforts. The handbook covers liquid Pb and LBE properties, materials compatibility and testing issues, key aspects of the thermal-hydraulics and system technologies, existing test facilities, open issues and perspectives. (author)

Chiral dynamics and heavy quark symmetry in a solvable toy field-theoretic model

International Nuclear Information System (INIS)

Bardeen, W.A.; Hill, C.T.

1994-01-01

We study a solvable QCD-like toy theory, a generalization of the Nambu--Jona-Lasinio model, which implements chiral symmetries of light quarks and heavy quark symmetry. The chiral symmetric and chiral broken phases can be dynamically tuned. This implies a parity-doubled heavy-light meson system, corresponding to a (0 - ,1 - ) multiplet and a (0 + ,1 + ) heavy spin multiplet. Consequently the mass difference of the two multiplets is given by a Goldberger-Treiman relation and g A is found to be small. The Isgur-Wise function ξ(w), the decay constant f B , and other observables are studied

Magnetic fluctuations in heavy fermion systems

International Nuclear Information System (INIS)

Broholm, C.L.

1989-06-01

Magnetic order and fluctuations in the heavy Fermion systems UPt 3 , U 2 Zn 17 and URu 2 Si 2 have been studied by neutron scattering. Single crystalline samples and triple-axis neutron-scattering techniques with energy transfers between 0 and 40 meV and energy resolutions between 0.1 meV and 4 meV have been employed. UPt 3 develops an antiferromagnetically ordered moment of (0.02±0.005) μ B below T N = 5 K which doubles the unit cell in the basal plane and coexists with superconductivity below T c = 0.5 K. The magnetic fluctuations are relaxational, and enhanced at the antiferromagnetic zone center in a low-energy regime. The characteristic zone-center relaxation energy is 0.3 meV. The temperature- and field-dependence of the antiferromagnetic order in the superconducting phase suggest a close relation between these two properties in UPt 3 . U 2 Zn 17 has a broad spectrum of magnetic fluctuations, even below T N = 9.7 K, of which the transverse part below 10 meV is strongly enhanced at the antiferromagnetic zone center. The system has an anomalously extended critical region and the antiferromagnetic phase transition seems to be driven by the temperature-dependence of an effective RKKY interaction, as anticipated theoretically. URu 2 Si 2 , a strongly anisotropic heavy Fermion system, has a high-energy regime of antiferromagnetically-correlated overdamped magnetic fluctuations. Below T N = 17.5 K weak antiferromagnetic order, μ = (0.04±0.01)μ B , with finite correlations along the tetragonal c axis, develops along with a low-energy regime of strongly dispersive singlet-singlet excitations. Below T c = 1 K antiferromagnetism coexists with superconductivity. A phenomenological model describing the exchange-enhanced overdamped magnetic fluctuations of heavy Fermion systems is proposed. Our experimental results are compared to the anomalous bulk properties of heavy Fermion systems, and to magnetic fluctuations in other metallic magnets. (orig.)

Comparison of the time behavior in the separation of light and heavy materials in X-ray backscattered method as a diagnostic tool in inspection

International Nuclear Information System (INIS)

Faezeh, Rahmani; Sepideh Sadat, Azimi; Esmaiel, Bayat; Vahid, Dost Mohammadi

2016-01-01

X-ray backscattered method based on Compton backscattering is used in the inspection field. In contrast to transmission method, source and detectors are positioned on one side of the target, so in the situation that transmission inspection is difficult, X-ray backscattered method can be provided suitable data in the inspection field. Also, detection of hidden explosives and narcotic materials are very difficult or impossible in transmission methods. High intensity backscattered beam from light materials (low-Z), such as explosives and narcotics, in comparison to the heavy materials (high-Z), made this method as the strong technique in inspection. X-ray and gamma photons scattered by the light material (such as PE and PTFE) as well as heavy material (such as Fe and Cu) were studied using MCNPX2.6 Monte Carlo code. The results showed that rise time of pulse from light materials are slower than that of from heavy materials due to multi scattering of low energy photons in the light ones, so time expansion would occur in signals from light elements. If measurement is possible, the difference in time behavior can be used as a novel method in complementary diagnostic tool beside the use of pulse height in X-ray backscattered method.

Superconductivity of tin and lead after heavy ion irradiation below 7.2 K

International Nuclear Information System (INIS)

Klaumuenzer, S.

1978-01-01

In this work the influence of radiation defects induced by heavy ion irradiation at low temperatures on the specific residual resistivity, the critical temperature of superconductivity, and the width of the resistive-superconductive phase transition have been measured for lead and tin as a function of dose and subsequent isochronous annealing. In the case of lead the critical magnetic field parallel to the surface of the sample, which in a wide range of defect contrations is identical with the surface superconductivity critical field, also has been measured at 5 K and 6 K as a function of dose and subsequent isochronous annealing. As projectiles 25 MeV oxygen ions have been used for irradiation, with a sufficiently low particle flux to obtain irradiation temperatures below about 7.2 K. However these temperatures are large enough to allow for free motion of interstitial atoms in the case of lead. For tin the results presented here also suggest free motion of the defects. (orig./WBU) [de

Green Synthesis of InP/ZnS Core/Shell Quantum Dots for Application in Heavy-Metal-Free Light-Emitting Diodes

OpenAIRE

Kuo, Tsung-Rong; Hung, Shih-Ting; Lin, Yen-Ting; Chou, Tzu-Lin; Kuo, Ming-Cheng; Kuo, Ya-Pei; Chen, Chia-Chun

2017-01-01

Quantum dot light-emitting diodes (QD-LEDs) have been considered as potential display technologies with the characterizations of high color purity, flexibility, transparency, and cost efficiency. For the practical applications, the development of heavy-metal-free QD-LEDs from environment-friendly materials is the most important issue to reduce the impacts on human health and environmental pollution. In this work, heavy-metal-free InP/ZnS core/shell QDs with different fluorescence were prepare...

Heavy metals in liquid pig manure in light of bacterial antimicrobial resistance

International Nuclear Information System (INIS)

Hölzel, Christina S.; Müller, Christa; Harms, Katrin S.; Mikolajewski, Sabine; Schäfer, Stefanie; Schwaiger, Karin; Bauer, Johann

2012-01-01

Heavy metals are regularly found in liquid pig manure, and might interact with bacterial antimicrobial resistance. Concentrations of heavy metals were determined by atomic spectroscopic methods in 305 pig manure samples and were connected to the phenotypic resistance of Escherichia coli (n=613) against 29 antimicrobial drugs. Concentrations of heavy metals (/kg dry matter) were 0.08–5.30 mg cadmium, 1.1–32.0 mg chrome, 22.4–3387.6 mg copper, <2.0–26.7 mg lead, <0.01–0.11 mg mercury, 3.1–97.3 mg nickel and 93.0–8239.0 mg zinc. Associated with the detection of copper and zinc, resistance rates against β-lactams were significantly elevated. By contrast, the presence of mercury was significantly associated with low antimicrobial resistance rates of Escherichia coli against β-lactams, aminoglycosides and other antibiotics. Effects of subinhibitory concentrations of mercury on bacterial resistance against penicillins, cephalosporins, aminoglycosides and doxycycline were also demonstrated in a laboratory trial. Antimicrobial resistance in the porcine microflora might be increased by copper and zinc. By contrast, the occurrence of mercury in the environment might, due to co-toxicity, act counter-selective against antimicrobial resistant strains.

Hadron production in light and heavy, quark and antiquark jets

International Nuclear Information System (INIS)

Baird, K.G.

1996-08-01

The authors review four hadronization studies performed by the SLD experiment at SLAC, involving separation of light (Z 0 → u anti u, d anti d, s anti s), c, and b flavors using precision vertexing, and separation of q- and anti q-jets using the highly polarized SLC electron beam. They measured the differences between the average charged multiplicities in Z 0 → light, → c anti c, and →b anti b events, and found that the results were consistent with predictions of perturbative QCD. Next, they measured π/Κ/p/Κ 0 /Λ 0 production in light events for the first time, and compared with production in c- and b-flavor events. They then examined particle production differences in light quark and antiquark hemispheres, and observed more high momentum baryons and K - 's than antibaryons and K + 's in quark hemispheres, consistent with the leading particle hypothesis. Lastly, they performed a search for jet handedness in light q- and anti q-jets. Assuming Standard Model values of quark polarization in Z 0 decays, they have set an improved upper limit on the analyzing power of the handedness method

Hydrogen radiolytic production in light and heavy water mixtures under conditions similar to LOCA (loss of coolant accidents)

International Nuclear Information System (INIS)

Garcia Rodenas, L.; Ali, S.P.; Liberman, S.J.

1987-01-01

H 2 , HD and D 2 radiolytic yield in heavy and light water mixtures has been determined to supply the necessary data which will allow to make a realistic estimation of the solution of such gas under LOCA conditions as a function of time. (Author)

Office lighting systems: Optimization

Energy Technology Data Exchange (ETDEWEB)

Dagnino, U. (ENEL, Milan (Italy))

1990-09-01

Relative to office lighting systems, in particular, those making use of tubular fluorescent lamps, currently available on the international market, this paper tries to develop lighting system, design optimization criteria. The comparative assessment of the various design possibilities considers operating cost, energy consumption, and occupational comfort/safety aspects such as lighting level uniformity and equilibrium, reduction of glare and reflection, natural/artificial lighting balance, programmed switching, computerized control systems for multi-use requirements in large areas, programmed maintenance for greater efficiency and reliability.

A diquark model for baryons containing one heavy quark

International Nuclear Information System (INIS)

Ebert, D.; Feldmann, T.; Kettner, C.; Reinhardt, H.

1995-06-01

We present a phenomenological ansatz for coupling a heavy quark with two light quarks to form a heavy baryon. The heavy quark is treated in the heavy mass limit, and the light quark dynamics is approximated by propagating scalar and axial vector 'diquarks'. The resulting effective lagrangian, which incorporates heavy quark and chiral symmetry, describes interactions of heavy baryons with Goldstone bosons in the low energy region. As an application, the Isgur-Wise formfactors are estimated. (orig.)

Experimental testing facilities for ultrasonic measurements in heavy liquid metal

International Nuclear Information System (INIS)

Cojocaru, V.; Ionescu, V.; Nicolescu, D.; Nitu, A.

2016-01-01

The thermo-physical properties of Heavy Liquid Metals (HLM), like lead or its alloy, Lead Bismuth Eutectic (LBE), makes them attractive as coolant candidates in advanced nuclear systems. The opaqueness, that is common to all liquid metals, disables all optical methods. For this reason ultrasound waves are used in different applications in heavy liquid metal technology, for example for flow and velocity measurements and for inspection techniques. The practical use of ultrasound in heavy liquid metals still needs to be demonstrated by experiments. This goal requires heavy liquid metal technology facility especially adapted to this task. In this paper is presented an experimental testing facility for investigations of Heavy Liquid Metals acoustic properties, designed and constructed in RATEN ICN. (authors)

Unified approach to the study of light and heavy mesons in the frameworkof the vacuum-polarization-corrected potential model

International Nuclear Information System (INIS)

Barik, N.; Jena, S.N.

1981-01-01

Phenomenological evidence from meson spectroscopy is presented to support the view that a unified description of bound light- and heavy-quark systems is possible within the scope of a nonrelativistic-potential-model approach. The vacuum-polarization-corrected potential with its confinement part in the form of an approximately equal admixture of vector and scalar components is found to be a suitable one for the purpose. The overall systematics of the predictions based on this potential model for the meson masses, fine-hyperfine splittings, leptonic decay widths, and the Regge slopes are observed to be consistent with the premise that the forces between quarks and antiquarks are independent of the quark flavors

Factorization for radiative heavy quarkonium decays into scalar Glueball

Energy Technology Data Exchange (ETDEWEB)

Zhu, Ruilin [INPAC, Shanghai Key Laboratory for Particle Physics and Cosmology,Department of Physics and Astronomy, Shanghai Jiao Tong University,Dongchuan RD 800, Shanghai 200240 (China); State Key Laboratory of Theoretical Physics,Institute of Theoretical Physics, Chinese Academy of Sciences,Zhongguancun E. St. 55, Beijing 100190 (China); CAS Center for Excellence in Particle Physics,Institute of High Energy Physics, Chinese Academy of Sciences,Yuquan RD 19B, Beijing 100049 (China)

2015-09-24

We establish the factorization formula for scalar Glueball production through radiative decays of vector states of heavy quarkonia, e.g. J/ψ, ψ(2S) and Υ(nS), where the Glueball mass is much less than the parent heavy quarkonium mass. The factorization is demonstrated explicitly at one-loop level through the next-to-leading order (NLO) corrections to the hard kernel, the non-relativistic QCD (NRQCD) long-distance matrix elements (LDMEs) of the heavy quarkonium, and the light-cone distribution amplitude (LCDA) of scalar Glueball. The factorization provides a comprehensive theoretical approach to investigate Glueball production in the radiative decays of vector states of heavy quarkonia and determine the physic nature of Glueball. We discuss the scale evolution equation of LCDA for scalar Glueball. In the end, we extract the value of the decay constant of Scalar Glueball from Lattice QCD calculation and analyze the mixing effect among f{sub 0}(1370), f{sub 0}(1500) and f{sub 0}(1710).

Implication of heavy metals distribution for a municipal solid waste management system - a case study in Shanghai

International Nuclear Information System (INIS)

Zhang Hua; He Pinjing; Shao Liming

2008-01-01

Heavy metal contamination in municipal solid waste (MSW) is of increasing concern. The occurrence and distribution of heavy metals in MSW and their implications for the integrated MSW management system in mega-cities have been investigated by means of material flow analysis based on a case study of Shanghai in China. A good statistical basis was provided through a one-year monitoring program on the mass and metals composition of the waste from three MSW treatment facilities. The results showed that the main heavy metals in the MSW were Zn, Cr, Cu, and Pb (on average > 100 mg kg -1 ), followed by Ni, Cd, and Hg. The MSW contained higher levels of Cu and Ni in metals, Cr and Pb in plastics, and Pb and Zn in the inorganic fractions. Regardless of the sources, the statistically similar heavy metal contents in the organic fractions indicated that effective blending and diffusion of heavy metals had taken place throughout the MSW collection, transfer, transportation, and storage, leading to cross-contamination of the waste fractions. PU (composed of putrescible waste and miscellaneous indistinguishable particles) contributed the majority of the heavy metals to the MSW, followed by plastics, as a result of the predominance in the overall composition of PU and plastics rather than from differences in their heavy metal contents. Therefore, manual or mechanical separation of some significantly heavy metal-rich fractions alone is not sufficient to reduce the heavy metal contents in the MSW. Source separation of organic waste and the diversion of tailored inorganic waste such as hazardous components, construction and demolition waste, etc., are proposed to control the heavy metal contamination in MSW. For the mixed MSW management system, physicochemical fractionation to exclude particles containing high levels of heavy metals can be conducted

Implication of heavy metals distribution for a municipal solid waste management system - a case study in Shanghai

Energy Technology Data Exchange (ETDEWEB)

Zhang Hua [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China); He Pinjing [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)], E-mail: solidwaste@mail.tongji.edu.cn; Shao Liming [State Key Laboratory of Pollution Control and Resources Reuse, Key Laboratory of Yangtze River Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092 (China)

2008-09-01

Heavy metal contamination in municipal solid waste (MSW) is of increasing concern. The occurrence and distribution of heavy metals in MSW and their implications for the integrated MSW management system in mega-cities have been investigated by means of material flow analysis based on a case study of Shanghai in China. A good statistical basis was provided through a one-year monitoring program on the mass and metals composition of the waste from three MSW treatment facilities. The results showed that the main heavy metals in the MSW were Zn, Cr, Cu, and Pb (on average > 100 mg kg{sup -1}), followed by Ni, Cd, and Hg. The MSW contained higher levels of Cu and Ni in metals, Cr and Pb in plastics, and Pb and Zn in the inorganic fractions. Regardless of the sources, the statistically similar heavy metal contents in the organic fractions indicated that effective blending and diffusion of heavy metals had taken place throughout the MSW collection, transfer, transportation, and storage, leading to cross-contamination of the waste fractions. PU (composed of putrescible waste and miscellaneous indistinguishable particles) contributed the majority of the heavy metals to the MSW, followed by plastics, as a result of the predominance in the overall composition of PU and plastics rather than from differences in their heavy metal contents. Therefore, manual or mechanical separation of some significantly heavy metal-rich fractions alone is not sufficient to reduce the heavy metal contents in the MSW. Source separation of organic waste and the diversion of tailored inorganic waste such as hazardous components, construction and demolition waste, etc., are proposed to control the heavy metal contamination in MSW. For the mixed MSW management system, physicochemical fractionation to exclude particles containing high levels of heavy metals can be conducted.

Nuclear structure studies with low-energy light ions: fundamental and applied

International Nuclear Information System (INIS)

Mazumdar, I.

2016-01-01

Studies in low and medium energy nuclear physics have been dominated by heavy-ion induced reactions for last five decades. Heavy-ion induced nuclear reactions have enriched our knowledge of the structural evolutions and intricacies of reaction dynamics of the nuclear many-body systems. However, the emergence and rise of heavy-ion physics have seen a general decline in studies with low- and medium-energy light-ion beams. The harsh reality of dwindling number of low-energy light ion facilities adversely affect research in nuclear physics. Very low-energy and high current light-ion facilities immediately conjures up in our minds the studies in nuclear astrophysics. Measurements of light-ion capture cross sections and astrophysical S factors are the major themes of research at most of the light-ion facilities. However, the importance low energy light-ion beams is multifarious. A variety of measurements providing vital support and inputs to heavy-ion research can only be carried out at the low-energy, light-ion facilities. Light-ion beams are also useful for generation of mono-energetic neutron beams. In this talk I will draw from some of our recent measurements to show the importance of light-ion beams in nuclear astrophysics and also in applied nuclear physics. (author)

An intranuclear cascade calculation of high-energy heavy-ion interactions

International Nuclear Information System (INIS)

Yariv, Y.; Fraenkel, Z.

1979-01-01

The intranuclear cascade model of Chen is extended to high-energy reactions between two heavy ions. The results of the calculations are compared with experimental results for the inclusive proton and pion cross sections, two-particle correlations, particle multiplicity distributions and spallation cross section distributions from light ( 12 C+ 12 C) to heavy( 40 Ar + 238 U) projectile-target systems in the laboratory bombarding energy range E/A=250-1000 MeV. The comparison shows that the model is fairly successful in reproducing the various aspects of high-energy reactions between heavy ions. It is also shown that the assumption that high particle multiplicities are indicative of ''central'' (small impact parameter) collisions are well founded for heavy projectile-target systems. (B.G.)

Determination of heavy metals contamination using a silicon sensor with extended responsive to the UV

International Nuclear Information System (INIS)

Aceves-Mijares, M; Ramírez, J M; Pedraza, J; Román-López, S; Chávez, C

2013-01-01

Due to its potential risk to human health and ecology, the presence of heavy metals in water demands of techniques to determine them in a simple and economical way. Currently, new developments of light emitters and detectors open a window of opportunities to use optical properties to analyze contaminated water. In this paper, a silicon sensor developed to extend its sensitivity up to the UV range is used to determine heavy metals in water. Cadmium, Zinc, Lead, Copper and Manganese mixed in pure water at different concentrations were used as test samples. The photocurrent obtained by the light that passes through the samples was used to determine the optical transmittance of pure and contaminated water. Preliminary results show a good separability between samples, which can be used for qualitative and quantitative detection of such heavy metals in water.

Moderator clean-up system in a heavy water reactor

International Nuclear Information System (INIS)

Sasada, Yasuhiro; Hamamura, Kenji.

1983-01-01

Purpose: To decrease the fluctuation of the poison concentration in heavy water moderator due to a heavy water clean-up system. Constitution: To a calandria tank filled with heavy water as poison-containing moderators, are connected both end of a pipeway through which heavy water flows and to which a clean-up device is provided. Strongly basic resin is filled within the clean-up device and a cooler is disposed to a pipeway at the upstream of the clean-up device. In this structure, the temperature of heavy water at the inlet of the clean-up device at a constant level between the temperature at the exit of the cooler and the lowest temperature for the moderator to thereby decrease the fluctuation in the poison concentration in the heavy water moderator due to the heavy water clean-up device. (Moriyama, K.)

Neutron absorption profile in a reactor moderated by different mixtures of light and heavy waters

International Nuclear Information System (INIS)

Nagy, Mohamed E.; Aly, Mohamed N.; Gaber, Fatma A.; Dorrah, Mahmoud E.

2014-01-01

Highlights: • We studied neutron absorption spectra in a mixed water moderated reactor. • Changing D 2 O% in moderator induced neutron energy spectral shift. • Most of the neutrons absorbed in control rods were epithermal. • Control rods worth changes were not proportional to changes of D 2 O% in moderator. • Control rod arrangement influenced the neutronic behavior of the reactor. - Abstract: A Monte-Carlo parametric study was carried out to investigate the neutron absorption profile in a model of LR-0 reactor when it is moderated by different mixtures of heavy/light waters at molecular ratios ranging from 0% up to 100% D 2 O at increments of 10% in D 2 O. The tallies included; neutron absorption profiles in control rods and moderator, and neutron capture profile in 238 U. The work focused on neutron absorption in control rods entailing; total mass of control rods needed to attain criticality, neutron absorption density and total neutron absorption in control rods at each of the studied mixed water moderators. The aim was to explore whether thermal neutron poisons are the most suitable poisons to be used in control rods of nuclear reactors moderated by mixed heavy/light water moderators

Summary report of the second research co-ordination meeting on improvement of the standard cross sections for light elements

International Nuclear Information System (INIS)

Carlson, A.D.; Hale, G.M.; Pronyaev, V.G.

2004-03-01

Results are presented following one and a half years of work under the Coordinated Research Project (CRP) on Improvement of the Standard Cross Sections for Light Elements. They include the use of the refined resonating group model for the theoretical prediction of the R-matrix poles and preliminary R-matrix model fits of the full experimental database for the 6 Li+n system obtained with different codes. Significant attention was paid to the exclusion of the bias in the evaluated data caused by the possible presence of Peelle's Pertinent Puzzle effect in the experimental data. Updates were also presented of the experimental database for light and heavy element standards including fission cross sections up to 200 MeV. First results and observed trends for all standard reactions are given, including the preliminary results of combining the model (for light elements) and non-model fits. The timetable for further work was agreed, which should lead to new reaction cross section standards for light and heavy elements by the end 2004. (author)

Isospin Conservation in Neutron Rich Systems of Heavy Nuclei

Science.gov (United States)

Jain, Ashok Kumar; Garg, Swati

2018-05-01

It is generally believed that isospin would diminish in its importance as we go towards heavy mass region due to isospin mixing caused by the growing Coulomb forces. However, it was realized quite early that isospin could become an important and useful quantum number for all nuclei including heavy nuclei due to neutron richness of the systems [1]. Lane and Soper [2] also showed in a theoretical calculation that isospin indeed remains quite good in heavy mass neutron rich systems. In this paper, we present isospin based calculations [3, 4] for the fission fragment distributions obtained from heavy-ion fusion fission reactions. We discuss in detail the procedure adopted to assign the isospin values and the role of neutron multiplicity data in obtaining the total fission fragment distributions. We show that the observed fragment distributions can be reproduced rather reasonably well by the calculations based on the idea of conservation of isospin. This is a direct experimental evidence of the validity of isospin in heavy nuclei, which arises largely due to the neutron-rich nature of heavy nuclei and their fragments. This result may eventually become useful for the theories of nuclear fission and also in other practical applications.

Impact of heavy metals on the female reproductive system

Directory of Open Access Journals (Sweden)

Piotr Rzymski

2015-05-01

Environmental deterioration can lead to the elevated risk of human exposure to heavy metals, and consequently, health implications including disturbances in reproduction. It is therefore important to continue the investigations on metal-induced mechanisms of fertility impairment on the genetic, epigenetic and biochemical level.

Matrix elements of Δ B =0 operators in heavy hadron chiral perturbation theory

Science.gov (United States)

Lee, Jong-Wan

2015-05-01

We study the light-quark mass and spatial volume dependence of the matrix elements of Δ B =0 four-quark operators relevant for the determination of Vu b and the lifetime ratios of single-b hadrons. To this end, one-loop diagrams are computed in the framework of heavy hadron chiral perturbation theory with partially quenched formalism for three light-quark flavors in the isospin limit; flavor-connected and -disconnected diagrams are carefully analyzed. These calculations include the leading light-quark flavor and heavy-quark spin symmetry breaking effects in the heavy hadron spectrum. Our results can be used in the chiral extrapolation of lattice calculations of the matrix elements to the physical light-quark masses and to infinite volume. To provide insight on such chiral extrapolation, we evaluate the one-loop contributions to the matrix elements containing external Bd, Bs mesons and Λb baryon in the QCD limit, where sea and valence quark masses become equal. In particular, we find that the matrix elements of the λ3 flavor-octet operators with an external Bd meson receive the contributions solely from connected diagrams in which current lattice techniques are capable of precise determination of the matrix elements. Finite volume effects are at most a few percent for typical lattice sizes and pion masses.

Green Lighting. Energy-efficient integrated lighting systems - Final report

Energy Technology Data Exchange (ETDEWEB)

Linhart, F.; Scartezzini, J.-L.

2009-10-15

The objective of the Green Lighting project was to develop a High Performance Integrated Lighting System, based on advanced technologies for day- and electric lighting, achieving a Lighting Power Density (LPD) that does not exceed 3 W/m{sup 2}. The project has revealed that Anidolic Daylighting Systems (ADS) are an ideal basis for High Performance Integrated Lighting Systems. Not only are they able to provide adequate illumination (i.e. sufficiently high illuminance) in office rooms during large fractions of normal office hours, under various sky conditions and over the entire year, but they are also highly appreciated by office occupants at the condition that glare control mechanisms are available. Complementary electric lighting is, however, still necessary to back up the ADS at times when there is insufficient daylight flux available. It was shown during this project, that the most interesting trade-offs between energy-efficiency and visual comfort are obtained by using a combination of ceiling-mounted directly emitting luminaires with very high optical efficiencies for ambient lighting and portable desk lamps for temporary task lighting. The most appropriate lamps for the ceiling-mounted luminaires are currently highly efficient fluorescent tubes, but white LED tubes can be considered a realistic option for the future. The most suitable light sources for desk lamps for temporary task lighting are Compact Fluorescent Lamps (CFLs) and white LED light bulbs. Based on the above-mentioned technologies, a High Performance Integrated Lighting System with a very low LPD has been developed over the last three years. The system has been set up in an office room of the LESO solar experimental building located on the EPFL campus; it has been tested intensively during a Post-Occupancy Evaluation (POE) study involving twenty human subjects. This study has revealed that the subjects' performance and subjective visual comfort was improved by the new system, compared to

Induction linacs for heavy ion fusion

International Nuclear Information System (INIS)

Keefe, D.

1986-11-01

Experimental progress to date has strengthened our belief in the soundness and attractiveness of the heavy ion method for fusion. What surprises that have shown up in the laboratory (e.g., in SBTE) have all been of the pleasant kind so far. The systems assessment has supported the view that the heavy ion approach can lead to economically attractive electric power and that a wide variety of options exists in all parameters. The systems work has also been of great help in pointing the way for the research and development activities

Decontamination of the RA reactor heavy water system, Annex 9

International Nuclear Information System (INIS)

Maksimovic, Z.B.; Nikolic, R.M.; Marinkovic, M.D.; Jelic, Lj.M.

1963-01-01

Both stainless steel and aluminium parts of the RA reactor heavy water system system were decontaminated as well as the heavy water itself. System was contaminated with 60 Co. Decontamination factor was determined by activity measurements during distillation. Concentration of the corrosion products in the heavy water was measured by spectrochemical analysis, and found to be 0.1 - 1 mg/l. Chemical analyses of the aluminium and stainless steel surfaces showed that cobalt was adsorbed on the aluminium oxide layer. Water solution of 7%H 3 PO 4 + 2% CrO 3 was used for decontamination of the heavy water system and distillation device. This was found to be the most efficient solvent which does not affect stainless steel corrosion. Decontamination factors achieved were from 60 - 100. Decontamination results enabled determining the distribution of cobalt in the system: 10 Ci on the stainless steel parts, 50 Ci in the heavy water; and above 600 Ci on the fuel and experimental channels. Specific activity of 60 Co was calculated to be 15 Ci/g on the reactor channels, 8 Ci/g on the stainless steel parts and 3 Ci/g in the heavy water. Decontamination of the aluminium parts was not done because it was considered it could initiate corrosion. Since the efficiency of distillation is increased it was expected that permanent distillation would remove most of the activity in the reactor channels

QCD Phenomenology and Light-Front Wavefunctions

International Nuclear Information System (INIS)

Brodsky, Stanley J.

2001-01-01

A natural calculus for describing the bound-state structure of relativistic composite systems in quantum field theory is the light-front Fock expansion which encodes the properties of a hadrons in terms of a set of frame-independent n-particle wavefunctions. Light-front quantization in the doubly-transverse light-cone gauge has a number of remarkable advantages, including explicit unitarity, a physical Fock expansion, the absence of ghost degrees of freedom, and the decoupling properties needed to prove factorization theorems in high momentum transfer inclusive and exclusive reactions. A number of applications are discussed in these lectures, including semileptonic B decays, two-photon exclusive reactions, diffractive dissociation into jets, and deeply virtual Compton scattering. The relation of the intrinsic sea to the light-front wavefunctions is discussed. Light-front quantization can also be used in the Hamiltonian form to construct an event generator for high energy physics reactions at the amplitude level. The light-cone partition function, summed over exponentially weighted light-cone energies, has simple boost properties which may be useful for studies in heavy ion collisions. I also review recent work which shows that the structure functions measured in deep inelastic lepton scattering are affected by final-state rescattering, thus modifying their connection to light-front probability distributions. In particular, the shadowing of nuclear structure functions is due to destructive interference effects from leading-twist diffraction of the virtual photon, physics not included in the nuclear light-cone wavefunctions

Influence of “Chelavite” Mineral Supplement Use on Cadmium and Lead Content in Blood, Wool and Milk of Heavy Cows

Directory of Open Access Journals (Sweden)

Anna Borisovna ANDREEVA

2015-07-01

Full Text Available The purpose of this research was to study the influence of this supplement use on the concentration of cadmium and lead in blood serum, wool and milk of heavy cows. The cows of milking herd of black-and-white breed, of 3-5 years old were the object of research. Their yearly milk production was 6 thousand litters (control and experimental group, each having 15 heads. The cows have been fed according to the balanced ration for heavy cows. The mineral supplement dose was determined according to the instruction for application for cows of experimental group with feed. The curative dose was 0.6 ml for 10 kg of body mass 1 time a day during 30 days. The samples were taken before giving the mineral supplement “Chelavite” and after the course had finished. The device Unicam AAS-939 was used to determine the cadmium and lead content in blood, wool and milk by way of atomic absorption spectrophotometry. It has been found that the cadmium level reduced by 2.35 times, the lead level reduced by 1,5 times in cows blood, the cadmium level reduced by 1.33 times, the lead level reduced by 4.34 times in cows wool, the cadmium level reduced by 2.2 times, the lead level reduced by 3.7 times in cows milk after giving them mineral supplement “Chelavite”. Thus, the application of chelate compounds in form of “Chelavite” for cows reduces concentration of heavy metals such as cadmium and lead. Then this is one of the ways to improve the milk quality.

Modelling and Simulation of SVPWM Based Vector Controlled HVDC Light Systems

Directory of Open Access Journals (Sweden)

Ajay Kumar MOODADLA

2012-11-01

Full Text Available Recent upgrades in power electronics technology have lead to the improvements of insulated gate bipolar transistor (IGBT based Voltage source converter High voltage direct current (VSC HVDC transmission systems. These are also commercially known as HVDC Light systems, which are popular in renewable, micro grid, and electric power systems. Out of different pulse width modulation (PWM schemes, Space vector PWM (SVPWM control scheme finds growing importance in power system applications because of its better dc bus utilization. In this paper, modelling of the converter is described, and SVPWM scheme is utilized to control the HVDC Light system in order to achieve better DC bus utilization, harmonic reduction, and for reduced power fluctuations. The simulations are carried out in the MATLAB/SIMULINK environment and the results are provided for steady state and dynamic conditions. Finally, the performance of SVPWM based vector controlled HVDC Light transmission system is compared with sinusoidal pulse width modulation (SPWM based HVDC Light system in terms of output voltage and total harmonic distortion (THD.

Fission delay and GDR γ-ray from very heavy system

International Nuclear Information System (INIS)

Shen, W.Q.; Wang, J.S.; Ye, W.; Cai, Y.H.; Ma, Y.G.; Feng, J.; Fang, D.Q.; Cai, X.Z.

1999-01-01

The study of the fission delay in reaction of 84 Kr+ 27 Al at 10.6 Mev/u and the systematics of fission delay are described. Authors also discussed the possibility to study the GDR γ rays emitted from the super-heavy compound system on the basis of the strong increasing of the GDR γ rays duo to the fission delay. The calculation results of the GDR γ rays from the super-heavy compound system via microscopic semi-classical Vlasov equation and the experimental data analysis for searching the super-heavy compound system via GDR γ were given

Hybrid daylight/light-emitting diode illumination system for indoor lighting.

Science.gov (United States)

Ge, Aiming; Qiu, Peng; Cai, Jinlin; Wang, Wei; Wang, Junwei

2014-03-20

A hybrid illumination method using both daylight and light-emitting diodes (LEDs) for indoor lighting is presented in this study. The daylight can be introduced into the indoor space by a panel-integration system. The daylight part and LEDs are combined within a specific luminaire that can provide uniform illumination. The LEDs can be turned on and dimmed through closed-loop control when the daylight illuminance is inadequate. We simulated the illumination and calculated the indoor lighting efficiency of our hybrid daylight and LED lighting system, and compared this with that of LED and fluorescent lighting systems. Simulation results show that the efficiency of the hybrid daylight/LED illumination method is better than that of LED and traditional lighting systems, under the same lighting conditions and lighting time; the method has hybrid lighting average energy savings of T5 66.28%, and that of the LEDs is 41.62%.

Contamination and Spatial Variation of Heavy Metals in the Soil-Rice System in Nanxun County, Southeastern China

Science.gov (United States)

Zhao, Keli; Fu, Weijun; Ye, Zhengqian; Zhang, Chaosheng

2015-01-01

There is an increasing concern about heavy metal contamination in farmland in China and worldwide. In order to reveal the spatial features of heavy metals in the soil-rice system, soil and rice samples were collected from Nanxun, Southeastern China. Compared with the guideline values, elevated concentrations of heavy metals in soils were observed, while heavy metals in rice still remained at a safe level. Heavy metals in soils and rice had moderate to strong spatial dependence (nugget/sill ratios: 13.2% to 49.9%). The spatial distribution of copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) in soils illustrated that their high concentrations were located in the southeast part. The high concentrations of cadmium (Cd) in soils were observed in the northeast part. The accumulation of all the studied metals is related to the long-term application of agrochemicals and industrial activities. Heavy metals in rice showed different spatial distribution patterns. Cross-correlograms were produced to quantitatively determine the spatial correlation between soil properties and heavy metals composition in rice. The pH and soil organic matter had significant spatial correlations with the concentration of heavy metals in rice. Most of the selected variables had clear spatial correlation ranges for heavy metals in rice, which could be further applied to divide agricultural management zones. PMID:25635917

Contamination and Spatial Variation of Heavy Metals in the Soil-Rice System in Nanxun County, Southeastern China

Directory of Open Access Journals (Sweden)

Keli Zhao

2015-01-01

Full Text Available There is an increasing concern about heavy metal contamination in farmland in China and worldwide. In order to reveal the spatial features of heavy metals in the soil-rice system, soil and rice samples were collected from Nanxun, Southeastern China. Compared with the guideline values, elevated concentrations of heavy metals in soils were observed, while heavy metals in rice still remained at a safe level. Heavy metals in soils and rice had moderate to strong spatial dependence (nugget/sill ratios: 13.2% to 49.9%. The spatial distribution of copper (Cu, nickel (Ni, lead (Pb and zinc (Zn in soils illustrated that their high concentrations were located in the southeast part. The high concentrations of cadmium (Cd in soils were observed in the northeast part. The accumulation of all the studied metals is related to the long-term application of agrochemicals and industrial activities. Heavy metals in rice showed different spatial distribution patterns. Cross-correlograms were produced to quantitatively determine the spatial correlation between soil properties and heavy metals composition in rice. The pH and soil organic matter had significant spatial correlations with the concentration of heavy metals in rice. Most of the selected variables had clear spatial correlation ranges for heavy metals in rice, which could be further applied to divide agricultural management zones.

Contamination and spatial variation of heavy metals in the soil-rice system in Nanxun County, Southeastern China.

Science.gov (United States)

Zhao, Keli; Fu, Weijun; Ye, Zhengqian; Zhang, Chaosheng

2015-01-28

There is an increasing concern about heavy metal contamination in farmland in China and worldwide. In order to reveal the spatial features of heavy metals in the soil-rice system, soil and rice samples were collected from Nanxun, Southeastern China. Compared with the guideline values, elevated concentrations of heavy metals in soils were observed, while heavy metals in rice still remained at a safe level. Heavy metals in soils and rice had moderate to strong spatial dependence (nugget/sill ratios: 13.2% to 49.9%). The spatial distribution of copper (Cu), nickel (Ni), lead (Pb) and zinc (Zn) in soils illustrated that their high concentrations were located in the southeast part. The high concentrations of cadmium (Cd) in soils were observed in the northeast part. The accumulation of all the studied metals is related to the long-term application of agrochemicals and industrial activities. Heavy metals in rice showed different spatial distribution patterns. Cross-correlograms were produced to quantitatively determine the spatial correlation between soil properties and heavy metals composition in rice. The pH and soil organic matter had significant spatial correlations with the concentration of heavy metals in rice. Most of the selected variables had clear spatial correlation ranges for heavy metals in rice, which could be further applied to divide agricultural management zones.

Electrons with continuous energy distribution from energetic heavy ion collisions

International Nuclear Information System (INIS)

Berenyi, D.

1984-01-01

The properties and origin of continuous electron spectrum emitted in high energy heavy ion collisions are reviewed. The basic processes causing the characteristic regions of the continuous spectrum are described. The contribution of electrons ejected from the target and from the projectile are investigated in detail in the cases of light and heavy projectiles. The recently recognized mechanisms, electron-capture-to-continuum (ECC) and electron-loss-to-continuum (ELC), leading to a cusp in forward direction, and their theoretical interpretations are discussed. The importance of data from ion-atom collisions in the field of atomic physics and in applications are briefly summarized. (D.Gy)

Autonomous photovoltaic lighting system

OpenAIRE

Hafez, Ahmed A. A.; Montesinos Miracle, Daniel; Sudrià Andreu, Antoni

2012-01-01

This paper introduces a comparison between the conventional and Photovoltaic (PV) lighting systems. A simple sizing procedure for a PV stand-alone system was advised. The paper also proposes a novel PV lighting system. The proposed system is simple, compact and reliable. The system operation was investigated by thoroughly mathematical and simulation work.

Preparation of rat gastric heavy and light microsomal membranes enriched in (H+-K+)-ATPase using 2H2O and Percoll gradients

International Nuclear Information System (INIS)

Im, W.B.; Davis, J.P.; Blakeman, D.P.

1985-01-01

Gastric heavy microsomal membranes highly enriched in (H + -K + )-ATPase were obtained from cimetidine- or carbachol-treated rats through 2 H 2 O and Percoll gradient centrifugations. Both the resting (cimetidine-treated) and the stimulated (carbachol-treated) heavy membranes which presumably represent the apical membrane of gastric parietal cells were enriched with the polypeptides of 81,000 and 45,000 besides that of 93,000 representing (H + -K + )-ATPase. No apparent differences could be detected between the resting and the stimulated heavy membranes in their polypeptide profiles or their specific activity of (H + -K + )-ATPase. Nevertheless, the level of 86 RbCl uptake was greater in the stimulated than the resting heavy microsomal membrane vesicles. The light gastric microsomes which abound in intracellular tubulovesicles containing reserve (H + -K + )-ATPase as isolated from cimetidine-treated rats were similarly purified with respect to (H + -K + )-ATPase. The purified light gastric membranes were largely devoid of the polypeptides of 81,000 and 45,000 found in the heavy gastric membranes. These observations further support the current hypothesis that secretagogues bring about changes in the environment of (H + -K + )-ATPase and induce KCl permeability in the apical membrane of the parietal cells, although at present the authors have been unable to identify the polypeptide(s) responsible for the KCl pathway

Light ion program at BNL

International Nuclear Information System (INIS)

Foelsche, H.; Barton, D.S.; Thieberger, P.

1986-08-01

At Brookhaven National Laboratory (BNL) two existing facilities, the Tandem Van de Graaff machines and the AGS have been joined by a beam transfer line, and modified to permit acceleration of light ions (up to sulfur) to energies of 14.6 GeV/amu. Light ions supplied by a pulsed ion source are accelerated by the Tandem to an energy of about 7 to 8 MeV/amu, and are transferred directly into the AGS in the fully stripped state. In the AGS an auxiliary rf system has been added to accelerate through the low velocity region from about 7 to about 200 MeV/amu, at which point the previously existing AGS RF system takes over to complete the acceleration cycle to full energy, as it normally does for protons. Standard resonant slow extraction delivers the beam to the existing experimental beam facilities. This is the first phase of a long range program to provide facilities for relativistic heavy ion experiments with fixed targets and ultimately with colliding beams at BNL. The design objectives for this project and preliminary results obtained during the commissioning of the light ion program are described in this paper. Plans for a future second phase, a booster accelerator to permit heavy ion acceleration in the AGS, and of the third phase, a proposed Relativistic Heavy Ion Collider (RHIC) are briefly mentioned as well

The heavy oil refiners needs in the future

International Nuclear Information System (INIS)

Sauer, J.W.

1991-01-01

In the 1970s oil crisis, the high price differential that developed between heavy and light crude led to an expansion in heavy crude processing geared to producing light oil products. The subsequent collapse in prices meant that heavy crudes with low netbacks were shut in, heavy crude refining capacity exceeded the restrained production of heavy crudes, and refineries were operating at losses. However, the low prices for oil rekindled demand and spare production capacity has been absorbed. The crude oil price is forecast to rise to ca $27/bbl by the late 1990s, which is favorable for heavy crude oil production. Nevertheless, investments in heavy crude production are exposed to a high degree of risk. A strategy for dealing with this risk is to integrate into downstream, which makes more sense for heavy crude producers than for conventional producers. On the other hand, such integration is capital-intensive, and light oils will likely be favored in crude oil production developments for the next several years. Low prices for natural gas will make it hard to find markets for residual fuel made from heavy crudes. 8 figs

Report of the heavy-ion fusion task group

International Nuclear Information System (INIS)

Sawyer, G.A.; Booth, L.A.; Henderson, D.B.; Jameson, R.A.; Kindel, J.M.; Knapp, E.A.; Pollock, R.; Talbert, W.L.; Thode, L.E.; Williams, J.M.

1980-02-01

An assessment of heavy-ion fusion has been completed. Energetic heavy ions, for example 10-GeV uranium, provided by an rf linac or an induction linac, are used as alternatives to laser light to drive inertial confinement fusion pellets. The assessment has covered accelerator technology, transport of heavy-ion beams, target interaction physics, civilian power issues, and military applications. It is concluded that particle accelerators promise to be efficient pellet drivers, but that there are formidable technical problems to be solved. It is recommended that a moderate level research program on heavy-ion fusion be pursued and that LASL should continue to work on critical issues in accelerator development, beam transport, reactor systems studies, and target physics over the next few years

Removal and recovery of tritium from light and heavy water

International Nuclear Information System (INIS)

Butler, J.P.; Hammerli, M.

1979-01-01

A method and apparatus for removing tritium from light water are described, comprising contacting tritiated feed water in a catalyst column in countercurrent flow with hydrogen gas originating from an electrolysis cell so as to enrich this feed water with tritium from the electrolytic hydrogen gas and passing the tritium enriched water to an electrolysis cell wherein the electrolytic hydrogen gas is generated and then fed upwards through the catalyst column or recovered as product. The tritium content of the hydrogen gas leaving the top of the enricher catalyst column is further reduced in a stripper column containing catalyst which transfers the tritium to a countercurrent flow of liquid water. Anodic oxygen and water vapour from the anode compartment may be fed to a drier and condensed electrolyte recycled with a slip stream or recovered as a further tritium product stream. A similar method involving heavy water is also described. (author)

PV led engine characterization lab for standalone light to light systems

DEFF Research Database (Denmark)

Thorsteinsson, Sune; Poulsen, Peter Behrensdorff; Lindén, Johannes

2014-01-01

PV-powered lighting systems, light-to-light systems (L2L), offer outdoor lighting where it is else where cumbersome to enable lighting. Application of these systems at high latitudes, where the difference in day length between summer and winter is large and the solar energy is low requires smart...... dimming functions for reliable lighting. In this work we have built a laboratory to characterize these systems up to 200 Wp from “nose to tail” in great details to support improvement of the systems and to make accurate field performance predictions....

Physical properties of root cementum: part 20. Effect of fluoride on orthodontically induced root resorption with light and heavy orthodontic forces for 4 weeks: a microcomputed tomography study.

Science.gov (United States)

Karadeniz, Ersan Ilsay; Gonzales, Carmen; Nebioglu-Dalci, Oyku; Dwarte, Dennis; Turk, Tamer; Isci, Devrim; Sahin-Saglam, Aynur M; Alkis, Huseyin; Elekdag-Turk, Selma; Darendeliler, M Ali

2011-11-01

The major side effect of orthodontic treatment is orthodontically induced inflammatory root resorption. Fluoride was previously shown to reduce the volume of the root resorption craters in rats. However, the effect of fluoride on orthodontically induced inflammatory root resorption in humans has not yet been investigated. The aim of this study was to investigate the effect of high and low amounts of fluoride intake from birth on orthodontically induced inflammatory root resorption under light (25 g) and heavy (225 g) force applications. Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected from 2 cities in Turkey with high and low fluoride concentrations in the public water of ≥ 2 and ≤ 0.05 ppm, respectively. The patients were randomly separated into 4 groups of 12 each: group 1, high fluoride intake and heavy force; group 2, low fluoride intake and heavy force; group 3, high fluoride intake and light force; and group 4, low fluoride intake and light force. Light or heavy buccal tipping orthodontic forces were applied on the maxillary first premolars for 28 days. At day 28, the teeth were extracted, and the samples were analyzed with microcomputed tomography. Fluoride reduced the volume of root resorption craters in all groups; however, this effect was significantly different with high force application (P = 0.015). It was also found that light forces caused less root resorption than heavy forces. There was no statistical difference in the amount of root resorption observed on root surfaces (buccal, lingual, mesial, and distal) in all groups. However, the middle third of the roots showed the least root resorption. With high fluoride intake and heavy force application, less root resorption was found in all root surfaces and root thirds. Fluoride may reduce the volume of root resorption craters. This effect is significant with heavy force applications (P root showed significantly greater root

NA49: lead-lead collision

CERN Multimedia

1996-01-01

This is an image of an actual lead ion collision taken from tracking detectors on the NA49 experiment, part of the heavy ion project at CERN. These collisions produce a very complicated array of hadrons as the heavy ions break up. It is hoped that one of these collisions will eventually create a new state of matter known as quark-gluon plasma.

The Use of Water Vapor for Detecting Environments that Lead to Convectively Produced Heavy Precipitation and Flash Floods

Science.gov (United States)

Scofield, Rod; Vicente, Gilberto; Hodges, Mike

2000-01-01

This Tech Report summarizes years of study and experiences on using GOES Water vapor (6.7 micron and precipitable water) and Special Sensor Microwave Imager (SSM/1) from the Defense Meteorological Satellite Program (DMSP) derived Precipitable Water (PNAI) for detecting environments favorable for convectively produced flash floods. An emphasis is on the moisture. upper air flow, and equivalent potential temperature (Theta(sub e)) patterns that lead to devastating flood events. The 15 minute 6.7 micron water vapor imagery is essential for tracking middle to upper tropospheric disturbances that produce upward vertical motion and initiate flash flood producing systems. Water vapor imagery at 6.7 micron is also used to detect surges of upper level moisture (called tropical water vapor plumes) that have been associated with extremely heavy rainfall. Since the water vapor readily depicts lifting mechanisms and upper level moisture, water vapor imagery is often an excellent source of data for recognizing patterns of heavy precipitation and flash floods. In order to analyze the depth of the moisture, the PW aspects of the troposphere must be measured. The collocation (or nearby location) of high values ofP\\V and instability are antecedent conditions prior to the flash flood or heavy rainfall events. Knowledge of PW magnitudes have been used as thresholds for impending flash flood events, PW trends are essential in flash flood prediction. Conceptual models and water vapor products are used to study some of the characteristics of convective systems that occurred over the United States of America (USA) during the summer of 1997 and the 1997-1998 El Nino. P\\V plumes were associated with most of the \\vest coast heavy precipitation events examined during the winter season of 1997 - 1998, In another study, conducted during the summer season of 1997. results showed that the collocation of water vapor (6.7 micron) and P\\N' plumes possessed higher correlations with predicted

Recent developments in heavy-ion fusion reactions around the Coulomb barrier

Directory of Open Access Journals (Sweden)

Hagino K.

2016-01-01

Full Text Available The nuclear fusion is a reaction to form a compound nucleus. It plays an important role in several circumstances in nuclear physics as well as in nuclear astrophysics, such as synthesis of superheavy elements and nucleosynthesis in stars. Here we discuss two recent theoretical developments in heavy-ion fusion reactions at energies around the Coulomb barrier. The first topic is a generalization of the Wong formula for fusion cross sections in a single-channel problem. By introducing an energy dependence to the barrier parameters, we show that the generalized formula leads to results practically indistinguishable from a full quantal calculation, even for light symmetric systems such as 12C+12C, for which fusion cross sections show an oscillatory behavior. We then discuss a semi-microscopic modeling of heavy-ion fusion reactions, which combine the coupled-channels approach to the state-of-the-art nuclear structure calculations for low-lying collective motions. We apply this method to subbarrier fusion reactions of 58Ni+58Ni and 40Ca+58Ni systems, and discuss the role of anharmonicity of the low-lying vibrational motions.

Light Heavy MSSM Higgs Bosons at Large tan $\\beta$

CERN Document Server

Ellis, Jonathan Richard; Olive, K A; Weiglein, G

2007-01-01

The region of MSSM Higgs parameter space currently excluded by the CDF Collaboration, based on an analysis of ~1 fb^-1 of integrated luminosity, is less than the expected sensitivity. We analyze the potential implications of the persistence of this discrepancy within the MSSM, assuming that the soft supersymmetry-breaking contributions to scalar masses are universal, apart from those to the Higgs masses (the NUHM model). We find that a light heavy MSSM Higgs signal in the unexcluded part of the sensitive region could indeed be accommodated in this simple model, even after taking into account other constraints from cold dark matter, electroweak precision observables and B physics observables. In this case the NUHM suggests that supersymmetric signatures should also be detectable in the near future in some other measurements such as BR(B_s -> mu+ mu-), BR(b -> s gamma) and (g-2)_mu, and M_h would have to be very close to the LEP exclusion limit. In addition, the dark matter candidate associated with this model ...

Physical properties of root cementum: Part 18. The extent of root resorption after the application of light and heavy controlled rotational orthodontic forces for 4 weeks: a microcomputed tomography study.

Science.gov (United States)

Wu, Andy T J; Turk, Tamer; Colak, Canan; Elekdağ-Turk, Selma; Jones, Allan S; Petocz, Peter; Darendeliler, M Ali

2011-05-01

The aim of this prospective randomized clinical trial was to quantitatively measure and compare the locations, dimensions, and volume of root resorption craters in human premolars after the application of controlled light and heavy rotational orthodontic forces over a 28-day (4-week) period. Fifteen patients requiring bilateral extraction of maxillary first premolars as part of their orthodontic treatment were recruited for this study. Each patient received a heavy (225 g) rotational force on 1 premolar and a light (25 g) rotational force on the contralateral premolar. Orthodontic rotational forces were applied over 28 days with buccal and palatal cantilever springs; 0.016-inch beta-titanium molybdenum alloys were used to apply the light force and 0.018-inch stainless steel was used for the heavy force. After the 28-day experimental period, the upper first premolars were extracted under stringent protocols to prevent root surface damage. The samples were then scanned using a microcomputed tomography (micro-CT) scan x-ray system (SkyScan 1072, Skyscan, Aartselaar, Belgium), and analyzed using convex hull algorithm (CHULL2D; University of Sydney, Sydney, Australia) software to obtain direct volumetric measurements. The mean volume of resorption craters was 0.42 in the light force group and 0.51 in the heavy force group (P = 0.013). When separated at the root level, the difference in volume of root resorption craters between the 2 groups was significantly different only at the midlevel (P = 0.001). Root resorption craters were consistently detected at the boundaries between the buccal and distal surfaces and the mesial and lingual surfaces. The result supports our hypothesis that positive areas develop significantly more root resorption craters at all 3 levels, as compared with minimal areas (paired t test root resorption than light rotational forces and compression areas (buccal-distal and lingual-mesial surfaces in this study) showed significantly higher root

Study of the continuum in heavy ion inelastic spectra by light particle coincidence measurements

International Nuclear Information System (INIS)

Scarpaci, J.A.; Blumenfeld, Y.; Chomaz, P.; Frascaria, N.; Garron, J.P.; Roynette, J.C.; Suomijarvi, T.; Van der Woude, A.; Alamanos, N.; Fernandez, B.; Gillibert, A.; Van der Woude, A.; Lepine, A.

1990-01-01

The continuum in heavy ion inelastic spectra contains, in addition to the excitation of target nucleus states, contributions from pick-up break-up and knock out reactions. In the case of the 40 Ca + 40 Ca collision at 50 MeV/N these contributions are separated and their relative importance assessed by the measurement of light charged particles in coincidence with the inelastically scattered fragments. The pick-up break-up contribution is found to make up less than half of the cross section at high excitation energies, conversely, the knock out process is important

Non-perturbative heavy quark effective theory. An application to semi-leptonic B-decays

International Nuclear Information System (INIS)

Della Morte, Michele; Heitger, Jochen; Simma, Hubert; Sommer, Rainer; Humboldt-Universitaet, Berlin

2015-01-01

We review a lattice strategy how to non-perturbatively determine the coefficients in the HQET expansion of all components of the heavy-light axial and vector currents, including 1/m h -corrections. We also discuss recent preliminary results on the form factors parameterizing semi-leptonic B-decays at the leading order in 1/m h .

Anatomy of lead poisoning | Duru | Research Journal of Health ...

African Journals Online (AJOL)

Objective: Lead poisoning and lead toxicity is usually often interchangeably used by different Scientists. The Anatomy of lead poisoning encompasses its effects on different organ-systems of different species of organisms. It also includes environmental, functional and biochemical components associated with most heavy ...

Heavy-quark pair production in gluon fusion at next-to-next-to-leading O(α4s) order. One-loop squared contributions

International Nuclear Information System (INIS)

Kniehl, B.A.; Merebashvili, Z.

2008-09-01

We calculate the next-to-next-to-leading order O(α 4 s ) one-loop squared corrections to the production of heavy quark pairs in the gluon-gluon fusion process. Together with the previously derived results on the q anti q production channel the results of this paper complete the calculation of the oneloop squared contributions of the next-to-next-to-leading order O(α 4 s ) radiative QCD corrections to the hadroproduction of heavy flavours. Our results, with the full mass dependence retained, are presented in a closed and very compact form, in dimensional regularization. (orig.)

Development of an intermediate energy heavy-ion micro-beam irradiation system

International Nuclear Information System (INIS)

Song Mingtao; Wang Zhiguang; He Yuan; Gao Daqing; Yang Xiaotian; Liu Jie; Su Hong; Man Kaidi; Sheng Li'na

2008-01-01

The micro-beam irradiation system, which focuses the beam down the micron order and precisely delivers a predefined number of ions to a predefined spot of micron order, is a powerful tool for radio-biology, radio-biomedicine and micromachining. The Institute of Modern Physics of Chinese Academy of Sciences is developing a heavy-ion micro-beam irradiation system up to intermediate energy. Based on the intermediate and low energy beam provided by Heavy Ion Research Facility of Lanzhou, the micro-beam system takes the form of the magnetic focusing. The heavy-ion beam is conducted to the basement by a symmetrical achromatic system consisting of two vertical bending magnets and a quadrupole in between. Then a beam spot of micron order is formed by magnetic triplet quadrupole of very high gradient. The sample can be irradiated either in vacuum or in the air. This system will be the first opening platform capable of providing heavy ion micro-beam, ranging from low (10 MeV/u) to intermediate energy (100 MeV/u), for irradiation experiment with positioning and counting accuracy. Target material may be biology cell, tissue or other non-biological materials. It will be a help for unveiling the essence of heavy-ion interaction with matter and also a new means for exploring the application of heavy-ion irradiation. (authors)

Heavy metal analysis in soils and vegetation for assessing emission fields near tunnel ventilation systems

International Nuclear Information System (INIS)

Peer, T.

1992-01-01

In the environment of the ventilation system of the Tauern and Katschberg tunnels, lead, cadmium, zinc and copper were determined in soil and vegetation samples in order to determine the emission fields. Thalli of Pseudevernia furfuracea in addition were used as active monitors. The surface-level exhaust portals produce relatively small atmospheric pollution fields. Via the detached exhaust tower at Urbanalm/Mosermandl (2.000 msm), a long-distance transport: Lead concentrations in soils are above average as far away as 1.5 kms of distance. The solubility of heavy metals increases in the order Pb [de

Opportunities for High-Value Bioblendstocks to Enable Advanced Light- and Heavy-Duty Engines: Insights from the Co-Optima Project

Energy Technology Data Exchange (ETDEWEB)

Farrell, John T [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2018-01-25

Co-Optima research and analysis have identified fuel properties that enable advanced light-duty and heavy-duty engines. There are a large number of blendstocks readily derived from biomass that possess beneficial properties. Key research needs have been identified for performance, technology, economic, and environmental metrics.

High dose, heavy ion implantation into metals: the use of sacrificial surface layers to enhance retention

International Nuclear Information System (INIS)

Clapham, L.

1994-01-01

While of considerable interest for the production of metallic alloys, high dose, heavy ion implantation is highly problematical, since the process is limited by sputtering effects. Sputtering is less significant, however, for light target materials, such as C and Al. This paper summarizes studies involving the use of light materials (such as C and Al) which act as slowly sputtering ''sacrificial layers'' when deposited on metallic targets prior to heavy ion implantation. The use of C and Al sacrificial coatings has enabled implanted ion retentions of 100% to be obtained in a number of ion-metal target systems, where the retentions in uncoated samples were as low as 20%. Ion implantation invariably leads to mixing at the sacrificial layer-metal target interface. This mixing may be detrimental in certain systems, so it is useful to be able to minimize or remove this mixed region. To achieve this, a number of techniques have been investigated: (1) removal of the mixed region in the latter stages of the implant; (2) using a barrier layer or chemical effects to minimize mixing at the sacrificial layer-metal interface; (3) choosing a sacrificial layer material which forms a mixed region which has desirable properties. The results of these investigations, for a number of different ion-target systems, are outlined in this paper. (orig.)

Engineering systems designs for a recirculating heavy ion induction accelerator

International Nuclear Information System (INIS)

Newton, M.A.; Barnard, J.J.; Reginato, L.L.; Yu, S.S.

1991-05-01

Recirculating heavy ion induction accelerators are being investigated as possible drivers for heavy ion fusion. Part of this investigation has included the generation of a conceptual design for a recirculator system. This paper will describe the overall engineering conceptual design of this recirculator, including discussions of the dipole magnet system, the superconducting quadrupole system and the beam acceleration system. Major engineering issues, evaluation of feasibility, and cost tradeoffs of the complete recirculator system will be presented and discussed. 5 refs., 4 figs

Cyclotron method for heavy ion acceleration

International Nuclear Information System (INIS)

Gikal, B.N.; Gul'bekyan, G.G.; Kutner, V.B.; Oganesyan, R.Ts.

1984-01-01

Studies on heavy ion beams in a wide range of masses (up to uranium) and energies disclose essential potential opportunities for solution of both fundamental scientific and significant economical problems. A cyclotron method for heavy ion acceleration is considered. Development of low and medium energy heavy ion accelerators is revealed. The design of a complex comprising two isochronous cyclotrons which is planned to be constrdcted 1n the JINR is described. The cyclotron complex includes the U-400 and the U-400 M cyclotrons and it is intended for acceleration of both 35-20 MeV/nucleon superheavy ions such as Xe-U and 120 MeV/nucleon light ions. Certain systems of the accelerators are described. Prospects of the U-400 and the U-400 M development are displayed

Light-induced lattice expansion leads to high-efficiency perovskite solar cells

Energy Technology Data Exchange (ETDEWEB)

Tsai, Hsinhan; Asadpour, Reza; Blancon, Jean-Christophe; Stoumpos, Constantinos C.; Durand, Olivier; Strzalka, Joseph W.; Chen, Bo; Verduzco, Rafael; Ajayan, Pulickel M.; Tretiak, Sergei; Even, Jacky; Alam, Muhammad Ashraf; Kanatzidis, Mercouri G.; Nie, Wanyi; Mohite, Aditya D.

2018-04-05

Hybrid-perovskite based high-performance optoelectronic devices and clues from their operation has led to the realization that light-induced structural dynamics play a vital role on their physical properties, device performance and stability. Here, we report that continuous light illumination leads to a uniform lattice expansion in hybrid perovskite thin-films, which is critical for obtaining high-efficiency photovoltaic devices. Correlated, in-situ structural and device characterizations reveal that light-induced lattice expansion significantly benefits the performances of a mixed-cation pure-halide planar device, boosting the power conversion efficiency from 18.5% to 20.5%. This is a direct consequence of the relaxation of local lattice strains during lattice expansion, which results in the reduction of the energetic barriers at the perovskite/contact interfaces in devices, thus improving the open circuit voltage and fill factor. The light-induced lattice expansion stabilizes these high-efficiency photovoltaic devices under continuous operation of full-spectrum 1-Sun illumination for over 1500 hours. One Sentence Summary: Light-induced lattice expansion improves crystallinity, relaxes lattice strain, which enhances photovoltaic performance in hybrid perovskite device.

QCD Phenomenology and Light-Front Wave Functions

International Nuclear Information System (INIS)

Brodsky, St.J.

2001-01-01

A natural calculus for describing the bound-state structure of relativistic composite systems in quantum field theory is the light-front Fock expansion which encodes the properties of a hadrons in terms of a set of frame-independent n-particle wave functions. Light-front quantization in the doubly-transverse light-cone gauge has a number of remarkable advantages, including explicit unitarity, a physical Fock expansion, the absence of ghost degrees of freedom, and the decoupling properties needed to prove factorization theorems in high momentum transfer inclusive and exclusive reactions. A number of applications are discussed in these lectures, including semileptonic B decays, two-photon exclusive reactions, diffractive dissociation into jets, and deeply virtual Compton scattering. The relation of the intrinsic sea to the light-front wave functions is discussed. Light-front quantization can also be used in the Hamiltonian form to construct an event generator for high energy physics reactions at the amplitude level. The light-cone partition function, summed over exponentially-weighted light-cone energies, has simple boost properties which may be useful for studies in heavy ion collisions. I also review recent work which shows that the structure functions measured in deep inelastic lepton scattering are affected by final-state rescattering, thus modifying their connection to light-front probability distributions. In particular, the shadowing of nuclear structure functions is due to destructive interference effects from leading-twist diffraction of the virtual photon, physics not included in the nuclear light-cone wave functions. (author)

Bioleaching combined brine leaching of heavy metals from lead-zinc mine tailings: Transformations during the leaching process.

Science.gov (United States)

Ye, Maoyou; Yan, Pingfang; Sun, Shuiyu; Han, Dajian; Xiao, Xiao; Zheng, Li; Huang, Shaosong; Chen, Yun; Zhuang, Shengwei

2017-02-01

During the process of bioleaching, lead (Pb) recovery is low. This low recovery is caused by a problem with the bioleaching technique. This research investigated the bioleaching combination of bioleaching with brine leaching to remove heavy metals from lead-zinc mine tailings. The impact of different parameters were studied, including the effects of initial pH (1.5-3.0) and solid concentration (5-20%) for bioleaching, and the effects of sodium chloride (NaCl) concentration (10-200 g/L) and temperature (25 and 50 °C) for brine leaching. Complementary characterization experiments (Sequential extraction, X-ray diffractometer (XRD), scanning electronic microscope (SEM)) were also conducted to explore the transformation of tailings during the leaching process. The results showed that bioleaching efficiency was significantly influenced by initial pH and solid concentration. Approximately 85.45% of iron (Fe), 4.12% of Pb, and 97.85% of zinc (Zn) were recovered through bioleaching in optimum conditions. Increasing the brine concentration and temperature promoted lead recovery. Lead was recovered from the bioleaching residues at a rate of 94.70% at 25 °C and at a rate of 99.46% at 50 °C when the NaCl concentration was 150 g/L. The study showed that bioleaching significantly changed the speciation of heavy metals and the formation and surface morphology of tailings. The metals were mainly bound in stable fractions after bioleaching. Copyright © 2016 Elsevier Ltd. All rights reserved.

Remediation of lead and cadmium-contaminated soils.

Science.gov (United States)

Salama, Ahmed K; Osman, Khaled A; Gouda, Neama Abdel-Razeek

2016-01-01

The research was designated to study the ability of plants to bio-accumulate, translocate and remove the heavy metals, lead and cadmium from contaminated soil. The herbal plant ryegrass, Lolium multiflorum was investigated as a bio-accumulator plant for these metals. The translocation of these heavy metals in the herbal plant was compared considering root to shoot transport and redistribution of metals in the root and shoot system. The trace metal contents from root and shoot parts were determined using atomic absorption spectrometer. The results showed that the percent of lead and cadmium transferred to ryegrass plant were averaged as 51.39, and 74.57%, respectively, while those remained in the soil were averaged as 48.61 and 25.43% following 60 days of treatment. The soil-plant transfer index in root and shoot system of ryegrass was found to be 0.32 and 0.20 for lead, and 0.50 and 0.25 for cadmium. These findings indicated that the herbal plant ryegrass, Lolium multiflorum is a good accumulator for cadmium than lead. The soil-plant transfer factor (the conc. of heavy metal in plant to the conc. in soil) indicated that the mechanism of soil remedy using the investigated plant is phytoextraction where the amounts of heavy metals transferred by plant roots into the above ground portions were higher than that remained in the soil. The method offers green technology solution for the contamination problem since it is effective technology with minimal impact on the environment and can be easily used for soil remedy.

Changes in muscle size and MHC composition in response to resistance exercise with heavy and light loading intensity

DEFF Research Database (Denmark)

Holm, Lars; Reitelseder, Søren; Pedersen, T.G.

2008-01-01

Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same indivi...... in healthy young men. However, LL resistance training was inferior to HL training in evoking adaptive changes in muscle size and contractile strength and was insufficient to induce changes in MHC composition.......Muscle mass accretion is accomplished by heavy-load resistance training. The effect of light-load resistance exercise has been far more sparsely investigated with regard to potential effect on muscle size and contractile strength. We applied a resistance exercise protocol in which the same.......05) in HL but remained unchanged in LL (4 +/- 5%, not significant). Finally, MHC IIX protein expression was decreased with HL but not LL, despite identical total workload in HL and LL. Our main finding was that LL resistance training was sufficient to induce a small but significant muscle hypertrophy...

Superconducting gap anomaly in heavy fermion systems

International Nuclear Information System (INIS)

Rout, G.C.; Ojha, M.S.; Behera, S.N.

2008-01-01

The heavy fermion system (HFS) is described by the periodic Anderson model (PAM), treating the Coulomb correlation between the f-electrons in the mean-field Hartree-Fock approximation. Superconductivity is introduced by a BCS-type pairing term among the conduction electrons. Within this approximation the equation for the superconducting gap is derived, which depends on the effective position of the energy level of the f-electrons relative to the Fermi level. The latter in turn depends on the occupation probability n f of the f-electrons. The gap equation is solved self-consistently with the equation for n f ; and their temperature dependences are studied for different positions of the bare f-electron energy level, with respect to the Fermi level. The dependence of the superconducting gap on the hybridization leads to a re-entrant behaviour with increasing strength. The induced pairing between the f-electrons and the pairing of mixed conduction and f-electrons due to hybridization are also determined. The temperature dependence of the hybridization parameter, which characterizes the number of electrons with mixed character and represents the number of heavy electrons is studied. This number is shown to be small. The quasi-particle density of states (DOS) shows the existence of a pseudo-gap due to superconductivity and the signature of a hybridization gap at the Fermi level. For the choice of the model parameters, the DOS shows that the HFS is a metal and undergoes a transition to the gap-less superconducting state. (author)

Impact of heavy metal toxicity and constructed wetland system as a tool in remediation.

Science.gov (United States)

Usharani, B; Vasudevan, N

2016-01-01

The objective of this review is to throw light upon the global concern of heavy metal-contaminated sites and their remediation through an ecofriendly approach. Accumulated heavy metals in soil and water bodies gain entry through the food chain and pose serious threat to all forms of life. This has engendered interest in phytoremediation techniques where hyperaccumulators are used. Constructed wetland has a pivotal role and is a cost-effective technique in the remediation of heavy metals. Metal availability and mobility are influenced by the addition of chelating agents, which enhance the availability of metal uptake. This review helps in identifying the critical knowledge gaps and areas to enhance research in the future to develop strategies such as genetically engineered hyperaccumulators to attain an environment devoid of heavy metal contamination.

Particle and heavy ion transport code system; PHITS

International Nuclear Information System (INIS)

Niita, Koji

2004-01-01

Intermediate and high energy nuclear data are strongly required in design study of many facilities such as accelerator-driven systems, intense pulse spallation neutron sources, and also in medical and space technology. There is, however, few evaluated nuclear data of intermediate and high energy nuclear reactions. Therefore, we have to use some models or systematics for the cross sections, which are essential ingredients of high energy particle and heavy ion transport code to estimate neutron yield, heat deposition and many other quantities of the transport phenomena in materials. We have developed general purpose particle and heavy ion transport Monte Carlo code system, PHITS (Particle and Heavy Ion Transport code System), based on the NMTC/JAM code by the collaboration of Tohoku University, JAERI and RIST. The PHITS has three important ingredients which enable us to calculate (1) high energy nuclear reactions up to 200 GeV, (2) heavy ion collision and its transport in material, (3) low energy neutron transport based on the evaluated nuclear data. In the PHITS, the cross sections of high energy nuclear reactions are obtained by JAM model. JAM (Jet AA Microscopic Transport Model) is a hadronic cascade model, which explicitly treats all established hadronic states including resonances and all hadron-hadron cross sections parametrized based on the resonance model and string model by fitting the available experimental data. The PHITS can describe the transport of heavy ions and their collisions by making use of JQMD and SPAR code. The JQMD (JAERI Quantum Molecular Dynamics) is a simulation code for nucleus nucleus collisions based on the molecular dynamics. The SPAR code is widely used to calculate the stopping powers and ranges for charged particles and heavy ions. The PHITS has included some part of MCNP4C code, by which the transport of low energy neutron, photon and electron based on the evaluated nuclear data can be described. Furthermore, the high energy nuclear

33 CFR 127.109 - Lighting systems.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Lighting systems. 127.109 Section... Waterfront Facilities Handling Liquefied Natural Gas § 127.109 Lighting systems. (a) The marine transfer area for LNG must have a lighting system and separate emergency lighting. (b) All outdoor lighting must be...

Magnetic moments of the lowest-lying singly heavy baryons

Science.gov (United States)

Yang, Ghil-Seok; Kim, Hyun-Chul

2018-06-01

A light baryon is viewed as Nc valence quarks bound by meson mean fields in the large Nc limit. In much the same way a singly heavy baryon is regarded as Nc - 1 valence quarks bound by the same mean fields, which makes it possible to use the properties of light baryons to investigate those of the heavy baryons. A heavy quark being regarded as a static color source in the limit of the infinitely heavy quark mass, the magnetic moments of the heavy baryon are determined entirely by the chiral soliton consisting of a light-quark pair. The magnetic moments of the baryon sextet are obtained by using the parameters fixed in the light-baryon sector. In this mean-field approach, the numerical results of the magnetic moments of the baryon sextet with spin 3/2 are just 3/2 larger than those with spin 1/2. The magnetic moments of the bottom baryons are the same as those of the corresponding charmed baryons.

The Semaphore crab, Heloecius cordiformis: bio-indication potential for heavy metals in estuarine systems.

Science.gov (United States)

MacFarlane; Booth; Brown

2000-09-01

Although alterations at the organism level in decapod crustaceans on exposure to heavy metals have been evidenced in the laboratory, little examination of metal effects on morphology and population parameters have been explored in a field-based situation. Relationships between morphological parameters, population demography and heavy metal sediment loadings were examined in conjunction with the accumulation of metals in the Semaphore crab, Heloecius cordiformis, in the Port Jackson and Hawkesbury River estuaries, Sydney, Australia. H. cordiformis exhibited sexual dimorphism, with males having larger carapace width, carapace length, chelae length and total mass than females. Sexes were subsequently treated separately to assess morphological differences among locations. Locations that had greater proportions of females with purple chelae and less females in the population tended to have higher sediment metal levels. These relationships were maintained over time, and could be employed as population-level biological indicators of heavy metal stress. Copper and zinc were regulated in the hepatopancreas of H. cordiformis. Lead was accumulated in the hepatopancreas of H. cordiformis in proportion to sediment lead levels, suggesting the species is both an appropriate candidate for bio-indication of lead pollution, and Pb is the main metal linked with population level differences. Accumulation of lead varied between sexes, indicating that sexes must be monitored separately. Smaller males accumulated more lead than larger males, suggesting size is an important consideration for lead accumulation.

Heavy-ion-spectrometer system

International Nuclear Information System (INIS)

1982-05-01

LBL safety policy (Pub 300 Appendix E) states that every research operation with a Class A risk potential (DOE 5484.1) should identify potentially hazardous procedures associated with the operation and develop methods for accomplishing the operation safely without personnel injury or property damage. The rules and practices that management deems to be minimally necessary for the safe operations of the Heavy Ion Spectrometer System (HISS) in the Bevatron Experimental Hall (51B) are set forth in this Operation Safety Procedures

Heavy-ion-spectrometer system

Energy Technology Data Exchange (ETDEWEB)

1982-05-01

LBL safety policy (Pub 300 Appendix E) states that every research operation with a Class A risk potential (DOE 5484.1) should identify potentially hazardous procedures associated with the operation and develop methods for accomplishing the operation safely without personnel injury or property damage. The rules and practices that management deems to be minimally necessary for the safe operations of the Heavy Ion Spectrometer System (HISS) in the Bevatron Experimental Hall (51B) are set forth in this Operation Safety Procedures (OSP).

Resolving the SELEX--LHCb Double-Charm Baryon Conflict: The Impact of Intrinsic Heavy-Quark Hadroproduction and Supersymmetric Light-Front Holographic QCD

Energy Technology Data Exchange (ETDEWEB)

Brodsky, Stanley [SLAC National Accelerator Lab., Menlo Park, CA (United States)

2017-01-01

In this paper we show that the intrinsic heavy-quark QCD mechanism for the hadroproduction of heavy hadrons at large $x_F$ can resolve the apparent conflict between measurements of double-charm baryons by the SELEX fixed-target experiment and the LHCb experiment at the LHC collider. We show that both experiments are compatible, and that both results can be correct. The observed spectroscopy of double-charm hadrons is in agreement with the predictions of supersymmetric light front holographic QCD.

Effect of fluoride on root resorption following heavy and light orthodontic force application for 4 weeks and 12 weeks of retention.

Science.gov (United States)

Karadeniz, Ersan I; Gonzales, Carmen; Turk, Tamer; Isci, Devrim; Sahin-Saglam, Aynur M; Alkis, Huseyin; Elekdag-Turk, Selma; Darendeliler, M Ali

2013-05-01

To evaluate the null hypothesis that fluoride intake via drinking water has no effect on orthodontic root resorption in humans after orthodontic force application for 4 weeks and 12 weeks of retention. Forty-eight patients who required maxillary premolar extractions as part of their orthodontic treatment were selected from two cities in Turkey. These cities had a high and low fluoride concentration in public water of ≥2 pm and ≤0.05 pm, respectively. The patients were randomly separated into four groups of 12 each: group 1HH, high fluoride (≥2 ppm) and heavy force (225 g); group 2LH, low fluoride (≤0.05 ppm) and heavy force; group 3HL, high fluoride and light force (25 g); and group 4LL, low fluoride and light force. Light or heavy buccal tipping force was applied on the upper first premolars for 28 days. At day 28, the left premolars were extracted (positive control side); the right premolars (experimental side) were extracted after 12 weeks of retention. The samples were analyzed with microcomputed tomography. On the positive control side, under heavy force application, the high fluoride groups exhibited less root resorption (P  =  .015). On the experimental side, it was found that fluoride reduced the total volume of root resorption craters; however, this effect was not statistically significant (P  =  .237). Moreover, the results revealed that under heavy force application experimental teeth exhibited more root resorption than positive control groups. The null hypothesis could not be rejected. High fluoride intake from public water did not have a beneficial effect on the severity of root resorption after a 4-week orthodontic force application and 12 weeks of passive retention.

Heavy metal biosorption by three bacteria isolated from a tropical river

African Journals Online (AJOL)

Bioaccumulation (bioconcentration) of four heavy metals cadmium, lead, zinc and nickel by three bacteria Bacillus, Staphylococcus and Pseudomonas as a tool for the decontamination of heavy metal impacted aquatic systems was investigated . The bacteria were obtained from the New Calabar River. Monitoring of the ...

Effect of ultraviolet light on fatigue of lead zirconate titanate thin-film capacitors

Science.gov (United States)

Lee, J.; Esayan, S.; Safari, A.; Ramesh, R.

1994-07-01

Fatigue of Pb(Zr0.52Ti0.48)O3 (PZT) thin-film capacitors was studied under UV light (He-Cd laser, λ=325 nm). The remanent polarization of the PZT film capacitors increased upon light illumination. Fatigue resistance was also improved under UV light. During fatigue test, the change in polarization of PZT films upon UV light illumination increased gradually with cycling. These results were examined within the framework of the polarization screening model, which is suggested as an essential process for fatigue. This leads to a conclusion that more charged defects are involved in the fatigue process through internal screening of polarization.

An inter-lighting interference cancellation scheme for MISO-VLC systems

Science.gov (United States)

Kim, Kyuntak; Lee, Kyujin; Lee, Kyesan

2017-08-01

In this paper, we propose an inter-lighting interference cancellation (ILIC) scheme to reduce the interference between adjacent light-emitting diodes (LEDs) and enhance the transmission capacity of multiple-input-single-output (MISO)-visible light communication (VLC) systems. In indoor environments, multiple LEDs have normally been used as lighting sources, allowing the design of MISO-VLC systems. To enhance the transmission capacity, different data should be simultaneously transmitted from each LED; however, that can lead to interference between adjacent LEDs. In that case, relatively low-received power signals are subjected to large interference because wireless optical systems generally use intensity modulation and direct detection. Thus, only the signal with the highest received power can be detected, while the other received signals cannot be detected. To solve this problem, we propose the ILIC scheme for MISO-VLC systems. The proposed scheme preferentially detects the highest received power signal, and this signal is referred as interference signal by an interference component generator. Then, relatively low-received power signal can be detected by cancelling the interference signal from the total received signals. Therefore, the performance of the proposed scheme can improve the total average bit error rate and throughput of a MISO-VLC system.

Heavy flavour and quarkonia measurement with ATLAS detector

CERN Document Server

Gallus, Petr; The ATLAS collaboration

2017-01-01

Charm and bottom quarks provide a powerful tool to study the properties of the hot, dense medium created in heavy ion collisions, and in particular may help differentiate between initial and final state effects in large collision systems. Measurements of open heavy flavour particle and quarkonia production, including their prompt and non-prompt components, and their correlations with light hadrons, build a path to understanding how heavy quarks propagate through the quark-gluon plasma. Additionally, an important component in these studies is the comparison between large and small collision systems. In this talk, ATLAS presents results on measurements of quarkonia production in PbPb collisions at 5.02 TeV, including separated prompt and non-prompt particle yields and a new measurement of the anisotropic flow of the J/Psi. The flow measurement provides information on the stage at which charmonium states are formed during the system evolution, thus giving insights on the effects that modify their production. Add...

Anticipatory stress restores decision-making deficits in heavy drinkers by increasing sensitivity to losses.

Science.gov (United States)

Gullo, Matthew J; Stieger, Adam A

2011-09-01

Substance abusers are characterized by hypersensitivity to reward. This leads to maladaptive decisions generally, as well as those on laboratory-based decision-making tasks, such as the Iowa Gambling Task (IGT). Negative affect has also been shown to disrupt the decision-making of healthy individuals, particularly decisions made under uncertainty. Neuropsychological theories of learning, including the Somatic Marker Hypothesis (SMH), argue this occurs by amplifying affective responses to punishment. In substance abusers, this might serve to rebalance their sensitivity to reward with punishment, and improve decision-making. Before completing the IGT, 45 heavy and 47 light drinkers were randomly assigned to a control condition, or led to believe they had to give a stressful public speech. IGT performance was analyzed with the Expectancy-Valence (EV) learning model. Working memory and IQ were also assessed. Heavy drinkers made more disadvantageous decisions than light drinkers, due to higher attention to gains (versus losses) on the IGT. Anticipatory stress increased participants' attention to losses, significantly improving heavy drinkers' decision-making. Anticipatory stress increased attention to losses, effectively restoring decision-making deficits in heavy drinkers by rebalancing their reward sensitivity with punishment sensitivity. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Various analytical techniques used for the measurement of isotopic purity of heavy water at Madras Atomic Power Station

International Nuclear Information System (INIS)

Satyanarayanan, V.; Umapathy, P.; Bhaskaran, R.; Nagarajan, J.; Pradeep, Jeena; Ayyar, S.R.

2008-01-01

The paper deals with the various techniques used for the measurement of isotopic purity of heavy water samples received from different sources viz. reactor systems, heavy water upgrading plant and fresh consignment from heavy water production plants. Heavy water is used in PHWRs as moderator and primary coolant. Isotopic Purity is an important parameter to be monitored/analysed regularly for both the systems. There is a minimum isotopic purity level to be maintained in the moderator system due to neutron economy/fuel burnup and in the case of coolant system the measurement is of paramount importance due to its safety considerations. The selection of the method of analysis depends on the isotopic range. The techniques used to measure the isotopic purity of heavy water are a) Infrared Spectrophotometry b) Refractometry c) Densitometry. Infrared spectrometer uses the property of molecular absorption of IR radiation by HOD species and the absorbance is the measure of isotopic purity. This technique is generally used for measuring high isotopic (80-99.98%) and low isotopic samples. Refractometer uses the property of refractive index of heavy water. The difference in refractive indices of light water and heavy water is 0.0048. A 1 % change in D 2 O concentration would thus equal to 0.000048 refractive index units. This method is used for determining the approximate isotopic value of a sample. Density meter uses the property of difference in densities of light and heavy water. The difference in density of 99.999% D 2 O and light water is 0.107540 which covers the whole range of interest. The experience gained with these techniques in the measurements of isotopic purity of various samples are presented in this paper. (author)

Scaling behaviour of leptonic decay constants for heavy quarkonia and heavy mesons

International Nuclear Information System (INIS)

Kiselev, V.V.

1994-01-01

In the framework of QCD sum rules one uses a scheme, allowing one to apply the conditions of both nonrelativistic heavy quark motion inside mesons and the heavy quark flavour independence of nonsplitting nS-state density. In the leading order an analitic expression is derived for leptonic constants of both heavy quarkonia and heavy mesons with a single heavy quark. The expression allows one explicitly to determine scaling properties of the constants. 24 refs., 2 tabs

Optimization of light quality from color mixing light-emitting diode systems for general lighting

Science.gov (United States)

Thorseth, Anders

2012-03-01

Given the problem of metamerisms inherent in color mixing in light-emitting diode (LED) systems with more than three distinct colors, a method for optimizing the spectral output of multicolor LED system with regards to standardized light quality parameters has been developed. The composite spectral power distribution from the LEDs are simulated using spectral radiometric measurements of single commercially available LEDs for varying input power, to account for the efficiency droop and other non-linear effects in electrical power vs. light output. The method uses electrical input powers as input parameters in a randomized steepest decent optimization. The resulting spectral power distributions are evaluated with regard to the light quality using the standard characteristics: CIE color rendering index, correlated color temperature and chromaticity distance. The results indicate Pareto optimal boundaries for each system, mapping the capabilities of the simulated lighting systems with regard to the light quality characteristics.

Potential surfaces in symmetric heavy-ion reactions

International Nuclear Information System (INIS)

Royer, G.; Piller, C.; Mignen, J.; Raffray, Y.

1989-01-01

The entrance channel in symmetric heavy-ion reactions is studied in the liquid-drop model approach including the nuclear proximity energy and allowing ellipsoidal deformations of the colliding nuclei. In the whole mass range a sudden transition occurs from oblate to prolate shapes when the proximity forces become important. This strongly affects the effective moment of inertia. The ellipsoidal deformations reduce the fusion barrier width for light systems and lower the potential barrier height for medium and heavy nuclei. The results are in agreement with the empirical effective barrier shift determined by Aguiar et al for the 58 Ni + 58 Ni, 74 Ge + 74 Ge and 80 Se + 80 Se systems. The sub-barrier fusion enhancement in heavy-ion reactions might be explained by the slowness of the process. Below the static fusion barrier, the reaction time is long; allowing some adiabaticity and deformations of the colliding ions. Above the barrier, the reaction is more sudden and the deformation degree of freedom is frozen

Reactivity requirements and safety systems for heavy water reactors

International Nuclear Information System (INIS)

Kati, S.L.; Rustagi, R.S.

1977-01-01

The natural uranium fuelled pressurised heavy water reactors are currently being installed in India. In the design of nuclear reactors, adequate attention has to be given to the safety systems. In recent years, several design modifications having bearing on safety, in the reactor processes, protective and containment systems have been made. These have resulted either from new trends in safety and reliability standards or as a result of feed-back from operating reactors of this type. The significant areas of modifications that have been introduced in the design of Indian PHWR's are: sophisticated theoretical modelling of reactor accidents, reactivity control, two independent fast acting systems, full double containment and improved post-accident depressurisation and building clean-up. This paper brings out the evolution of design of safety systems for heavy water reactors. A short review of safety systems which have been used in different heavy water reactors, of varying sizes, has been made. In particular, the safety systems selected for the latest 235 MWe twin reactor unit station in Narora, in Northern India, have been discussed in detail. Research and Development efforts made in this connection are discussed. The experience of design and operation of the systems in Rajasthan and Kalpakkam reactors has also been outlined

Heavy-flavour transport: from large to small systems

Energy Technology Data Exchange (ETDEWEB)

Beraudo, A.; De Pace, A.; Monteno, M.; Nardi, M.; Prino, F.

2016-12-15

Predictions for heavy-flavour production in relativistic heavy-ion experiments provided by the POWLANG transport setup, including now also an in-medium hadronization model, are displayed, After showing some representative findings for the Au-Au and Pb-Pb cases, a special focus will be devoted to the results obtained in the small systems formed in proton(deuteron)-nucleus collisions, where recent experimental data suggest the possible formation of a medium featuring a collective behaviour.

CAB models for water: A new evaluation of the thermal neutron scattering laws for light and heavy water in ENDF-6 format

International Nuclear Information System (INIS)

Márquez Damián, J.I.; Granada, J.R.; Malaspina, D.C.

2014-01-01

Highlights: • We present a new evaluation of the thermal scattering laws for light and heavy water. • This evaluation is based on molecular and experimental data, with no free parameters. • Calculations with these libraries compare well with experimental values. • Libraries result in an improvement over existing ENDF scattering law files. - Abstract: In this work we present the CAB models for water: a set of new models for the evaluation of the thermal neutron scattering laws for light and heavy water in ENDF-6 format, using the LEAPR module of NJOY. These models are based on experimental structure data and frequency spectra computed from molecular dynamics simulations. The calculations show a significant improvement over ENDF/B-VI and ENDF/B-VII when compared with measurements of differential and integral scattering data

Issues facing the management of radioactively contaminated lead within the DOE system

International Nuclear Information System (INIS)

Gilmore, M.C.; Kent, S.H.

1993-01-01

The purpose of this paper is to discuss and evaluate the issues that managing and operating contractors in the US DOE system should consider that are associated with management of radioactively contaminated elemental lead. There are many instances where DOE contaminated lead fall within Resource Conservation and Recovery Act (RCRA) regulation. In light of the Federal Facilities Compliance Act (FFCA), it is becoming increasingly important for additional regulatory options to be explored in order to facilitate proper treatment, storage and disposal of RCRA regulated lead. Various DOE facilities have initiated processes to reuse or recycle contaminated lead. Technologies such as melt-refining, surface blasting, and electromigration are being explored. One or more of these technologies may be the key to reducing contaminated lead inventories in the DOE system. Many DOE facilities are finding that these efforts need to have stringent regulatory evaluation since some alternatives have proven to be environmentally desirable but not economically feasible

Determination of distribution pattern of the heavy metal concentrations in the potable network of Gachsaran by Geographical Information System (GIS

Directory of Open Access Journals (Sweden)

G Paraham

2013-12-01

. Methods: In this descriptive, cross-sectional study, samples were taken from11 spots of the drinking water distribution network and tested for concentration of 10 metals by Inductivity Coupled Ions Plasma (ICP method in summer of 2010. The research data were compared with national and international water standards. Then the distribution map of heavy metals concentrations in the drinking water wells of the region was prepared by using the Geographical Information System (GIS software. Data were analyzed by the Kruskal-Wallis tests. Results: In all samples, the average concentration of heavy metals were: Arsenic 0.54, Cadmium 0.05, Zinc 55.9, Lead 0.18, Copper .82, Chromium 1.6, Barium 36.5, Selenium0.5, Mercury 0.1 and Silver 0.05 micrograms per liter and was less than the water quality standard. Conclusion: Based on the results obtained, it can be concluded that concentrations of heavy metals in Gachsaran’s drinking water distribution network are not higher than national and international standards and therefore not harmful for people. Key words: Heavy metals, Distribution network, Gachsaran, geographical information system (GIS

Heavy metal balances: Part I. General aspects of cadmium, copper, zinc and lead balance studies in agro-ecosystems

NARCIS (Netherlands)

Moolenaar, S.W.; Lexmond, T.M.

1999-01-01

The control of heavy metals in such a way that soil functioning and product quality are not impeded is a prerequisite to sustainable agriculture. The current status of heavy metal accumulation in agricultural soils differs widely by region, by metal, and by agricultural system; levels of concern

Heavy Higgs boson with a light sneutrino next-to-lightest supersymmetric particle in the MSSM with enhanced SU(2) D-terms

International Nuclear Information System (INIS)

Medina, Anibal D.; Shah, Nausheen R.; Wagner, Carlos E. M.

2009-01-01

The minimal supersymmetric extension of the standard model provides a solution to the hierarchy problem and leads to the presence of a light Higgs. A Higgs boson with mass above the present experimental bound may only be obtained for relatively heavy third generation squarks, requiring a precise, somewhat unnatural balance between different contributions to the effective Higgs mass parameter. It was recently noticed that somewhat heavier Higgs bosons, which are naturally beyond the CERN LEP bound, may be obtained by enhanced weak SU(2) D-terms. Such contributions appear in models with an enhanced electroweak gauge symmetry, provided the supersymmetry breaking masses associated with the scalars responsible for the breakdown of the enhanced gauge symmetry group to the standard model one are larger than the enhanced symmetry breaking scale. In this article we emphasize that the enhanced SU(2) D-terms will not only raise the Higgs boson mass but also affect the spectrum of the nonstandard Higgs bosons, sleptons, and squarks, which therefore provide a natural contribution to the T parameter, compensating for the negative one coming from the heavy Higgs boson. The sleptons and nonstandard Higgs bosons of these models, in particular, may act in a way similar to the so-called inert Higgs doublet. The phenomenological properties of these models are emphasized, and possible cosmological implications as well as collider signatures are described.

Detecting heavy quarks

International Nuclear Information System (INIS)

Benenson, G.; Chau, L.L.; Ludlam, T.; Paige, F.E.; Platner, E.D.; Protopopescu, S.D.; Rehak, P.

1983-01-01

In this exercise we examine the performance of a detector specifically configured to tag heavy quark (HQ) jets through direct observations of D-meson decays with a high resolution vertex detector. To optimize the performance of such a detector, we assume the small diamond beam crossing configuration as described in the 1978 ISABELLE proposal, giving a luminosity of 10 32 cm -2 sec -1 . Because of the very large backgrounds from light quark (LQ) jets, most triggering schemes at this luminosity require high P/sub perpendicular to/ leptons and inevitably give missing neutrinos. If alternative triggering schemes could be found, then one can hope to find and calculate the mass of objects decaying to heavy quarks. A scheme using the high resolution detector will also be discussed in detail. The study was carried out with events generated by the ISAJET Monte Carlo and a computer simulation of the described detector system

Using stable lead isotopes to trace heavy metal contamination sources in sediments of Xiangjiang and Lishui Rivers in China.

Science.gov (United States)

Sun, Guo-Xin; Wang, Xin-Jun; Hu, Qin-Hong

2011-12-01

Lead isotopes and heavy metal concentrations were measured in two sediment cores sampled in estuaries of Xiangjiang and Lishui Rivers in Hunan province, China. The presence of anthropogenic contribution was observed in both sediments, especially in Xiangjiang sediment. In the Xiangjiang sediment, the lower (206)Pb/(207)Pb and higher (208)Pb/(206)Pb ratio, than natural Pb isotope signature (1.198 and 2.075 for (206)Pb/(207)Pb and (208)Pb/(206)Pb, respectively), indicated a significant input of non-indigenous Pb with low (206)Pb/(207)Pb and high (208)Pb/(206)Pb. The corresponding concentrations of heavy metals (As, Cd, Zn, Mn and Pb) were much higher than natural values, suggesting the contaminations of heavy metals from extensive ore-mining activities in the region. Copyright © 2011 Elsevier Ltd. All rights reserved.

New heavy crude oil flow improver increases delivery : application scenarios

Energy Technology Data Exchange (ETDEWEB)

Pierce, J.; Johnston, R.; Lauzon, P. [ConocoPhillips Specialty Products Inc., Houston, TX (United States)

2009-07-01

Flow improvers or drag reducing agents have been used for over 25 years as a method to increase fluid flow in hydrocarbon pipelines. The technology is effective in refined projects, light and medium crude oils. This paper presented a new development in flow improver technology that allows treatment of heavy crude oil slates. It discussed case studies of flow improver treatment of heavy oils in various pipeline system as well as factors that affect commercial success. tabs., figs.

Heavy quark effective theory and study of heavy hadron spectra

International Nuclear Information System (INIS)

Dong Yubing

1995-01-01

By employing the heavy quark effective theory, the spectra of heavy hadrons, such as heavy mesons (Q-barq), heavy baryons (QQq and Qqq) and heavy multiquark systems (Q-barQ-barqq) are studied systemically. The results are compared with the predictions for Q-barQ-barqq in potential model

Entropy, baryon asymmetry and dark matter from heavy neutrino decays

International Nuclear Information System (INIS)

Buchmueller, W.; Schmitz, K.; Vertongen, G.

2011-01-01

The origin of the hot phase of the early universe remains so far an unsolved puzzle. A viable option is entropy production through the decays of heavy Majorana neutrinos whose lifetimes determine the initial temperature. We show that baryogenesis and the production of dark matter are natural by-products of this mechanism. As is well known, the cosmological baryon asymmetry can be accounted for by leptogenesis for characteristic neutrino mass parameters. We find that thermal gravitino production then automatically yields the observed amount of dark matter, for the gravitino as the lightest superparticle and typical gluino masses. As an example, we consider the production of heavy Majorana neutrinos in the course of tachyonic preheating associated with spontaneous B-L breaking. A quantitative analysis leads to constraints on the superparticle masses in terms of neutrino masses: For a light neutrino mass of 10 -5 eV the gravitino mass can be as small as 200 MeV, whereas a lower neutrino mass bound of 0.01 eV implies a lower bound of 9 GeV on the gravitino mass. The measurement of a light neutrino mass of 0.1 eV would rule out heavy neutrino decays as the origin of entropy, visible and dark matter.

Entropy, baryon asymmetry and dark matter from heavy neutrino decays

Energy Technology Data Exchange (ETDEWEB)

Buchmueller, W.; Schmitz, K.; Vertongen, G.

2011-04-15

The origin of the hot phase of the early universe remains so far an unsolved puzzle. A viable option is entropy production through the decays of heavy Majorana neutrinos whose lifetimes determine the initial temperature. We show that baryogenesis and the production of dark matter are natural by-products of this mechanism. As is well known, the cosmological baryon asymmetry can be accounted for by lepto- genesis for characteristic neutrino mass parameters. We nd that thermal gravitino production then automatically yields the observed amount of dark matter, for the gravitino as the lightest superparticle and typical gluino masses. As an example, we consider the production of heavy Majorana neutrinos in the course of tachyonic preheating associated with spontaneous B-L breaking. A quantitative analysis leads to contraints on the superparticle masses in terms of neutrino masses: For a light neutrino mass of 10{sup -5} eV the gravitino mass can be as small as 200 MeV, whereas a lower neutrino mass bound of 0.01 eV implies a lower bound of 9 GeV on the gravitino mass. The measurement of a light neutrino mass of 0.1 eV would rule out heavy neutrino decays as the origin of entropy, visible and dark matter. (orig.)

No increased systemic fibrinolysis in women with heavy menstrual bleeding

NARCIS (Netherlands)

Wiewel-Verschueren, S.; Knol, H. M.; Lisman, T.; Bogchelman, D. H.; Kluin-Nelemans, J. C.; van der Zee, A.G.J.; Mulder, A.B.; Meijer, K.

BackgroundBleeding disorders have been recognized as important etiologic or contributory factors in women with heavy menstrual bleeding. Fibrinolysis in the endometrium plays a role in heavy menstrual bleeding. It is unknown whether increased systemic fibrinolysis might also increase the risk of

Update on Heavy-Meson Spectrum Tests of the Oktay--Kronfeld Action

Energy Technology Data Exchange (ETDEWEB)

Bailey, Jon A. [Seoul Natl. U.; Jang, Yong-Chull [Seoul Natl. U.; Lee, Weonjong [Seoul Natl. U.; DeTar, Carleton [Utah U.; Kronfeld, Andreas S. [TUM-IAS, Munich; Oktay, Mehmet B. [Iowa U.

2016-01-18

We present updated results of a numerical improvement test with heavy-meson spectrum for the Oktay--Kronfeld (OK) action. The OK action is an extension of the Fermilab improvement program for massive Wilson fermions including all dimension-six and some dimension-seven bilinear terms. Improvement terms are truncated by HQET power counting at $\\mathrm{O}(\\Lambda^3/m_Q^3)$ for heavy-light systems, and by NRQCD power counting at $\\mathrm{O}(v^6)$ for quarkonium. They suffice for tree-level matching to QCD to the given order in the power-counting schemes. To assess the improvement, we generate new data with the OK and Fermilab action that covers both charm and bottom quark mass regions on a MILC coarse $(a \\approx 0.12~\\text{fm})$ $2+1$ flavor, asqtad-staggered ensemble. We update the analyses of the inconsistency quantity and the hyperfine splittings for the rest and kinetic masses. With one exception, the results clearly show that the OK action significantly reduces heavy-quark discretization effects in the meson spectrum. The exception is the hyperfine splitting of the heavy-light system near the $B_s$ meson mass, where statistics are too low to draw a firm conclusion, despite promising results.

Measurement of concentration of heavy water

International Nuclear Information System (INIS)

Tsukamoto, Yuichi; Kondo, Mitsuo; Sakurai, Naoyuki

1979-01-01

The concentration of heavy water is measured as one of the technical management in the Fugen plant. The heavy water is used as the moderator in the reactor. The measuring method depends on the theory of light absorption. The light absorption range of heavy water spreads from near infrared to infrared zone. The near infrared absorption was adopted for the purpose, as the absorption is much larger in infrared zone, and the measurement has to be conducted, limiting the apparent absorption. This measuring method is available to determine the concentration of heavy water in the broad range exactly. The preparation of heavy water sample and the measurement of the absorption spectra of near infrared ray are explained, as the experimental procedure. The sample cell was made of quartz, and the spectroscope was the Hitachi 323 type. The resolving power is 100 nm and 27 nm for the wave length of 1000 nm and 2500 nm, respectively. Concerning the measured results, the absorption was recorded in the wave length range from 600 nm to 2600 nm, and for the heavy water concentration range from 0 to 99.77 wt. %. The peaks of absorption were located at the wave length of 1450, 1660, 1920, 1970, 2020 and 2600 nm. The three kinds of fundamental vibration mode of the molecules of both light and heavy water are shown, and the peaks belong to H 2 O, HDO and D 2 O, respectively. The relation between the absorption and the heavy water concentration, and that between the transmissivity and the wave length are shown, when the cell thickness was varied to 5 mm and 20 mm, and the heavy water concentration to 21%, 62% and 99.85%. (Nakai, Y.)

40 CFR Appendix Xii to Part 86 - Tables for Production Compliance Auditing of Heavy-Duty Engines and Heavy-Duty Vehicles...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Tables for Production Compliance Auditing of Heavy-Duty Engines and Heavy-Duty Vehicles, Including Light-Duty Trucks XII Appendix XII to... Appendix XII to Part 86—Tables for Production Compliance Auditing of Heavy-Duty Engines and Heavy-Duty...

Modeling of Heavy Metal Transformation in Soil Ecosystem

Science.gov (United States)

Kalinichenko, Kira; Nikovskaya, Galina N.

2017-04-01

The intensification of industrial activity leads to an increase in heavy metals pollution of soils. In our opinion, sludge from biological treatment of municipal waste water, stabilized under aerobic-anaerobic conditions (commonly known as biosolid), may be considered as concentrate of natural soil. In their chemical, physical and chemical and biological properties these systems are similar gel-like nanocomposites. These contain microorganisms, humic substances, clay, clusters of nanoparticles of heavy metal compounds, and so on involved into heteropolysaccharides matrix. It is known that microorganisms play an important role in the transformation of different nature substances in soil and its health maintenance. The regularities of transformation of heavy metal compounds in soil ecosystem were studied at the model of biosolid. At biosolid swelling its structure changing (gel-sol transition, weakening of coagulation contacts between metal containing nanoparticles, microbial cells and metabolites, loosening and even destroying of the nanocomposite structure) can occur [1, 2]. The promotion of the sludge heterotrophic microbial activities leads to solubilization of heavy metal compounds in the system. The microbiological process can be realized in alcaligeneous or acidogeneous regimes in dependence on the type of carbon source and followed by the synthesis of metabolites with the properties of flocculants and heavy metals extragents [3]. In this case the heavy metals solubilization (bioleaching) in the form of nanoparticles of hydroxycarbonate complexes or water soluble complexes with oxycarbonic acids is observed. Under the action of biosolid microorganisms the heavy metals-oxycarbonic acids complexes can be transformed (catabolised) into nano-sizing heavy metals- hydroxycarbonates complexes. These ecologically friendly complexes and microbial heteropolysaccharides are able to interact with soil colloids, stay in the top soil profile, and improve soil structure due

Heavy electron superconductivity: From 1K to 90K to ?

International Nuclear Information System (INIS)

Pethick, C.J.; Pines, D.

1987-01-01

This paper reviews the experimental results and physical arguments which led us to conclude that in heavy electron systems the physical mechanism responsible for superconductivity is an attractive interaction between the heavy electrons which results from the virtual exchange of antiferromagnetic f-electron moment fluctuations. In these systems, then, the superconductivity is of purely electronic origin; the phonon-induced interaction between electrons which leads to superconductivity in ordinary metals plays little or no role

Radiogenic lead with dominant content of {sup 208}Pb: New coolant and neutron moderator for innovative nuclear reactors

Energy Technology Data Exchange (ETDEWEB)

Shmelev, A. N.; Kulikov, G. G.; Kryuchkov, E. F.; Apse, V. A.; Kulikov, E. G. [National Research Nuclear Univ. MEPhI, Kashirskoe shosse, 31, 115409, Moscow (Russian Federation)

2012-07-01

The advantages of radiogenic lead with dominant content of {sup 208}Pb as a reactor coolant with respect to natural lead are caused by unique nuclear properties of {sup 208}Pb which is a double-magic nucleus with closed proton and neutron shells. This results in significantly lower micro cross section and resonance integral of radiative neutron capture by {sup 208}Pb than those for numerous light neutron moderators. The extremely weak ability of {sup 208}Pb to absorb neutrons results in the following effects. Firstly, neutron moderating factor (ratio of scattering to capture cross sections) is larger than that for graphite and light water. Secondly, age and diffusion length of thermal neutrons are larger than those for graphite, light and heavy water. Thirdly, neutron lifetime in {sup 208}Pb is comparable with that for graphite, beryllium and heavy water what could be important for safe reactor operation. The paper presents some results obtained in neutronics and thermal-hydraulics evaluations of the benefits from the use of radiogenic lead with dominant content of {sup 208}Pb instead of natural lead as a coolant of fast breeder reactors. The paper demonstrates that substitution of radiogenic lead for natural lead can offer the following benefits for operation of fast breeder reactors. Firstly, improvement of the reactor safety thanks to the better values of coolant temperature reactivity coefficient and, secondly, improvement of some thermal-hydraulic reactor parameters. Radiogenic lead can be extracted from thorium sludge without isotope separation as {sup 208}Pb is a final isotope in the decay chain of {sup 232}Th. (authors)

Heavy liquid metal technologies at KArlsruhe Lead LAboratory KALLA

International Nuclear Information System (INIS)

Knebel, J.U.; Mueller, G.; Konys, J.

2002-01-01

The objectives of the research cover: lead-bismuth technologies; corrosion mechanism and corrosion protection; thermal hydraulics; kinetics of oxygen control systems. Detailed experimental results are presented

Dibaryon states containing two different types of heavy quarks

International Nuclear Information System (INIS)

Leandri, J.; Silvestre-Brac, B.

1995-01-01

In a recent series of papers we have shown that including heavy quarks in the dibaryon sector can lead to configurations stable against decay into two baryons. In this study we extend our previous work by a study of all the physical Q 2 q 4 [Q denotes a heavy quark and q denotes a member of the SU(3) F triplet representation] systems in a solvable chromomagnetic model. We propose a number of new heavy states which could be stable under strong interactions

Procedure for operating a heavy water cooled power reactor

International Nuclear Information System (INIS)

Rau, P.; Kumpf, H.

1981-01-01

Nuclear reactors cooled by heavy water usually have equipment for fuel element exchange during operation, with the primary circuit remaining contained. This fuel element exchange equipment is expensive and complicated in many respects. According to the invention, the heavy water is therefore replaced by light water after a certain time of operation in such way that light water is led in and heavy water is led off. After the replacement, at least a quarter of the fuel elements of the reactor core is exchanged with the reactor pressure vessel being open. Then the light water serving as a shielding is replaced by heavy water, with the reactor pressure vessel being closed. The invention is of interest particularly for high-conversion reactors. (orig.) [de

Study of the contamination of forages and legumes by lead and heavy metals

Energy Technology Data Exchange (ETDEWEB)

Delcarte, E; Impens, R; Kirchmann, R; Nangniot, P; Fagniart, E

1975-01-01

A description of the methods used by the authors for their study of contamination of the environment and of the food chain by heavy metals is presented with particular reference to lead, cadmium and zinc. The first phase consists of taking samples, in industrial and urban areas and in the vicinity of highways, of soil and various common plants, including Plantago major L. (greater plantain), Ligustrum sp. (privet), Trifolium repens L. (white clover) and Tussilago farfara L. (coltsfoot). Concentrations of metal substances in these samples are measured by means of oscillopolarography at a set voltage. Risk areas are thus demarcated where fodder, vegetable and fruit samples are taken regularly throughout the vegetation period. A watch is kept on the progress and extent of Zn, Cd, Pb, Ni, Co and Cu fall-out in vegetable gardens and orchards in the vicinity of smelters in the Meuse valley. The results are compared with those obtained in the suburbs of Brussels near highway intersections and in a control area, away from any source of pollution. These results reveal that there is a serious risk of chronic poisoning in human beings and animals which feed on contaminated plants. Parallel laboratory tests are being carried out on the absorption, retention and toxicity of these metal substances in plants. The results obtained using stable lead and /sup 210/lead in Zea mays L. (maize) are discussed. Finally, dairy cattle are being experimentally fed on fodder which has been artificially enriched with stable lead and /sup 210/lead. The aim is to calculate the rate of alimentary lead transfer to the milk, urine and feces.

Charge and angular distributions as well as sequential decay and γ-ray emission in heavy ion collisions viewed in the light of the diffusion model

International Nuclear Information System (INIS)

Moretto, L.G.

1977-08-01

The hierarchy of the collective relaxation times in heavy ion reactions is briefly reviewed. An improved diffusion model is introduced and applied to interpret the fragment Z and angular distributions for some typical reactions. The equilibrium in the neutron-to-proton ratio as well as the sharing of the excitation energy between fragments is studied by a coincidence method which leads to the measurement of the charge, mass and mean number of nucleons emitted by each fragment. The final destiny of the dissipative energy is determined by measuring the atomic number of two coincident fragments, thus obtaining the missing charge as a function of bombarding energy and the Q of the reaction. The sequential fission probability of the heavy recoil is established as a function of the Z and kinetic energy of the light partner. The out-of-plane angular distribution of the fission fragments is correlated with the fissionability and interpreted in terms of various sources of angular momentum misalignment. The γ-ray multiplicities and the γ-ray angular distributions associated with deep inelastic event are discussed in terms of the angular momentum transfer and in terms of the diffusion model

Soft Gluon Radiation off Heavy Quarks beyond Eikonal Approximation

International Nuclear Information System (INIS)

Mazumder, Surasree; Bhattacharyya, Trambak; Abir, Raktim

2016-01-01

We calculate the soft gluon radiation spectrum off heavy quarks (HQs) interacting with light quarks (LQs) beyond small angle scattering (eikonality) approximation and thus generalize the dead-cone formula of heavy quarks extensively used in the literatures of Quark-Gluon Plasma (QGP) phenomenology to the large scattering angle regime which may be important in the energy loss of energetic heavy quarks in the deconfined Quark-Gluon Plasma medium. In the proper limits, we reproduce all the relevant existing formulae for the gluon radiation distribution off energetic quarks, heavy or light, used in the QGP phenomenology.

Antimicrobial resistance, heavy metal resistance and integron content in bacteria isolated from a South African tilapia aquaculture system.

Science.gov (United States)

Chenia, Hafizah Y; Jacobs, Anelet

2017-11-21

Antibacterial compounds and metals co-select for antimicrobial resistance when bacteria harbour resistance genes towards both types of compounds, facilitating the proliferation and evolution of antimicrobial and heavy metal resistance. Antimicrobial and heavy metal resistance indices of 42 Gram-negative bacteria from a tilapia aquaculture system were determined to identify possible correlations between these phenotypes. Agar dilution assays were carried out to determine susceptibility to cadmium, copper, lead, mercury, chromate and zinc, while susceptibility to 21 antimicrobial agents was investigated by disk diffusion assays. Presence of merA, the mercury resistance gene, was determined by dot-blot hybridizations and PCR. Association of mercury resistance with integrons and transposon Tn21 was also investigated by PCR. Isolates displayed a high frequency of antimicrobial (erythromycin: 100%; ampicillin: 85%; trimethoprim: 78%) and heavy metal (Zn2+: 95%; Cd2+: 91%) resistance. No correlation was established between heavy metal and multiple antibiotic resistance indices. Significant positive correlations were observed between heavy metal resistance profiles, indices, Cu2+ and Cr3+ resistance with erythromycin resistance. Significant positive correlations were observed between merA (24%)/Tn21 (24%) presence and heavy metal resistance profiles and indices; however, significant negative correlations were obtained between integron-associated qacE∆1 (43%) and sulI (26%) gene presence and heavy metal resistance indices. Heavy metal and antimicrobial agents co-select for resistance, with fish-associated, resistant bacteria demonstrating simultaneous heavy metal resistance. Thus, care should be taken when using anti-fouling heavy metals as feed additives in aquaculture facilities.

Vacuum system control for the Heavy Ion Transport Line

International Nuclear Information System (INIS)

Stattel, P.; Feigenbaum, I.; Hseuh, H.C.; Robinson, T.; Skelton, R.; Wong, V.

1987-01-01

The Brookhaven AGS, 807 m in circumference, and the Tandem Van de Graaff are now joined together by a transport line, 600 m in length. This now allows heavy ions from the Tandem, up to fully stripped sulfur (M = 32) to be transported into the AGS and accelerated to 15 GeV/A. With the addition of a booster between the Tandem and the AGS in the near future, heavy ions such as gold (M = 200) can be accelerated to 30 Z/A GeV/A. This paper describes the HITL (Heavy Ion Transport Line) vacuum control system design and implementation

Design and development of an improved traffic light control system using hybrid lighting system

Directory of Open Access Journals (Sweden)

Michael Osigbemeh

2017-02-01

Full Text Available The deployment of light emitting diodes (LEDs based traffic system control created the problem of dim displays when ambient light is similar to traffic lights. It causes some drivers' disability of seeing and obeying traffic signs. This makes drivers violate traffic rules. In this paper, an attempt to use hybrid lighting technology to mitigate this problem was developed. Incandescent lightings with deployed halogen bulbs provided an instantaneous source of highly efficacious illumination which is brighter than the drivers' ambient lights (both daylight, electrical lights and their reflections, which can help drivers get access to enough warning and help them initiate traffic safety warning as necessary. The halogen lightings also offered the required high current draw needed in electrical circuitry to help brighten the LED displays. The problem of heat generated was eliminated by aerating the T-junction traffic light control unit designed for this technology. The result of hybrid lighting system design was found to be high luminosity and capability of gaining driver attention in real-time. It also allowed enhanced sign's image detection and processing for smart based technologies by providing the “light punch” needed for a wide range of visual concerns.

1. contribution of the dynamics on the reactions mechanisms in the heavy ions collisions at the intermediary energies (20-100 MeV/A) for the light systems. 2. management of radioactive wastes by new options: nuclear data measurement programme between 20 and 150 MeV; 1. role de la dynamique sur les mecanismes de reactions dans les collisions d'ions lourds aux energies intermediaires (20-100 MeV/A) pour des systemes legers. 2. gestion des dechets radioactifs par des options nouvelles: programme de mesures de donnees nucleaires entre 20 et 150 MeV

Energy Technology Data Exchange (ETDEWEB)

Eudes, Ph

2000-09-22

The first part concerns the features of emitted charged particles in heavy ions reactions that have been studied in the framework of the semi classical Landau-Vlasov approach for the light system Ar + Al at 65 MeV/nucleon incident energy. The second part is devoted to the radioactive waste management (transmutation), but it was necessary to increase the data banks evaluated in neutrons up to 150-200 MeV and to create a data bank in protons. In the European framework it was decide to focus on three representative elements: lead (spallation target), iron (structure material) and uranium (actinide). (N.C.)

1. contribution of the dynamics on the reactions mechanisms in the heavy ions collisions at the intermediary energies (20-100 MeV/A) for the light systems. 2. management of radioactive wastes by new options: nuclear data measurement programme between 20 and 150 MeV; 1. role de la dynamique sur les mecanismes de reactions dans les collisions d'ions lourds aux energies intermediaires (20-100 MeV/A) pour des systemes legers. 2. gestion des dechets radioactifs par des options nouvelles: programme de mesures de donnees nucleaires entre 20 et 150 MeV

Energy Technology Data Exchange (ETDEWEB)

Eudes, Ph

2000-09-22

The first part concerns the features of emitted charged particles in heavy ions reactions that have been studied in the framework of the semi classical Landau-Vlasov approach for the light system Ar + Al at 65 MeV/nucleon incident energy. The second part is devoted to the radioactive waste management (transmutation), but it was necessary to increase the data banks evaluated in neutrons up to 150-200 MeV and to create a data bank in protons. In the European framework it was decide to focus on three representative elements: lead (spallation target), iron (structure material) and uranium (actinide). (N.C.)

Empirical membrane lifetime model for heavy duty fuel cell systems

Science.gov (United States)

Macauley, Natalia; Watson, Mark; Lauritzen, Michael; Knights, Shanna; Wang, G. Gary; Kjeang, Erik

2016-12-01

Heavy duty fuel cells used in transportation system applications such as transit buses expose the fuel cell membranes to conditions that can lead to lifetime-limiting membrane failure via combined chemical and mechanical degradation. Highly durable membranes and reliable predictive models are therefore needed in order to achieve the ultimate heavy duty fuel cell lifetime target of 25,000 h. In the present work, an empirical membrane lifetime model was developed based on laboratory data from a suite of accelerated membrane durability tests. The model considers the effects of cell voltage, temperature, oxygen concentration, humidity cycling, humidity level, and platinum in the membrane using inverse power law and exponential relationships within the framework of a general log-linear Weibull life-stress statistical distribution. The obtained model is capable of extrapolating the membrane lifetime from accelerated test conditions to use level conditions during field operation. Based on typical conditions for the Whistler, British Columbia fuel cell transit bus fleet, the model predicts a stack lifetime of 17,500 h and a membrane leak initiation time of 9200 h. Validation performed with the aid of a field operated stack confirmed the initial goal of the model to predict membrane lifetime within 20% of the actual operating time.

Investigation of the heavy water distillation system at the RA reactor

International Nuclear Information System (INIS)

Zecevic, V.; Badrljica, R.

1963-01-01

The heavy water distillation system was tested because this was not done before the reactor start-up. Detailed inspection of the system components showed satisfactory results. Leak testing was done as well as the testing of the instrumentation which enables reliable performance of the system. Performance testing was done with ordinary water and later 2700 l of heavy water from the reactor was purified, decreasing the activity by 45%

A Preliminary Version of Heavy Ion Treatment Planning System at IMP

International Nuclear Information System (INIS)

Liu Xinguo; Dai Zhongying; Ye Fei; Wu Qingfeng; Li Ping; Li Qiang; Jin Xiaodong; Du Xiaogang; WangYangping; Dang Jianwu

2010-01-01

Based on the Heavy Ion Research Facility in Lanzhou (HIRFL/HIRFL-CSR), clinical trials of heavy ion radiotherapy are being conducted at the Institute of Modern Physics (IMP), Chinese Academy of Sciences, where two-dimensional(2D) layer-stacking conformal irradiation method in a passive beam delivery system was applied. To make better use of the biophysical advantages of heavy ion beams and ensure success of the clinical trials, a preliminary version of heavy ion treatment planning system (TPS) has been developed at IMP. The TPS was designed in a manner to adapt to the 2D layer-stacking conformal irradiation method. The architecture and function of the TPS software and the implementation of dose calculation algorithm in the TPS were introduced in this paper.The deviation between the doses planned by the TPS and measured through an anthropomorphous phantom was verified to be less than 5%. Finally,the pending issues for developing a sophisticated treatment planning system at IMP were discussed. (authors)

Design of Heavy Metals Monitoring System in Water Based on WSN and GPRS

Directory of Open Access Journals (Sweden)

Ke Lin

2014-04-01

Full Text Available In order to realize the real-time monitoring of heavy metals in water environment, a new type of heavy metal monitoring system was developed. The system was composed of monitoring terminal, gateway, GPRS network and upper computer monitoring center. The system detected the heavy metal ion concentrations by ion-selective electrode array and came into the system error automatic compensation method in the detection process. The collecting data was transported to the monitoring center through the cooperation between the wireless sensor network constituted by CC2530 and General Packet Radio Service network. The test result shows that the system can increased precision dramatically and strengthens the real-time transmission capacity effectively. The system is reliable in transmission, high real-time performance, flexible in networking and can be applied to continuous remote monitoring of heavy metals pollution.

Heavy Ion Fusion Systems Assessment study

International Nuclear Information System (INIS)

Dudziak, D.J.; Herrmannsfeldt, W.B.

1986-07-01

The Heavy Ion Fusion Systems Assessment (HIFSA) study was conducted with the specific objective of evaluating the prospects of using induction linac drivers to generate economical electrical power from inertial confinement fusion. The study used algorithmic models of representative components of a fusion system to identify favored areas in the multidimensional parameter space. The resulting cost-of-electricity (COE) projections are comparable to those from other (magnetic) fusion scenarios, at a plant size of 100 MWe

Safety system in a heavy water detritiation plant

International Nuclear Information System (INIS)

Balteanu, O.; Stefan, I.; Retevoi, C.

2003-01-01

In a CANDU 6 type reactor a quantity of 55·10 15 Bq/year of tritium is generated, 95% being in the D 2 O moderator which can achieve a radioactivity of 2.5-3.5·10 12 Bq/kg. Tritium in heavy water contributes with 30-50% to the doses received by operation personnel and up to 20% to the radioactivity released in the environment. The large quantity of heavy water used in this type of reactors (500 tones) make storage very difficult, especially for environment. The extraction of tritium from tritiated heavy water of CANDU reactors solve the following problems: the radiation level in the operation area, the costs of maintenance and repair reduction due to reduction of personnel protection measures, the increase of NPP utilisation factor by shutdown time reduction for maintenance and repair, use the extracted tritium for fusion reactors and not for the last, lower costs and risk for storage heavy water waste. Heavy water detritiation methods, which currently are used in the industrial or experimental plant, are based on catalytic isotope exchange or electrolysis followed cryogenic distillation or permeation. The technology developed at Institute of Cryogenics and Isotope Separation is based upon catalytic exchange between tritiated water and deuterium, followed by cryogenic distillation of hydrogen isotopes. The nature of the fluids that are processed in detritiation requires the operation of the plant in safety conditions. The paper presents the safety system solution chose in order to solve this task, as well as a simulation of an incident and safety system response. The application software is using LabView platform that is specialised on control and factory automation applications. (author)

Heavy-quark pair production in gluon fusion at next-to-next-to-leading O({alpha}{sup 4}{sub s}) order. One-loop squared contributions

Energy Technology Data Exchange (ETDEWEB)

Kniehl, B.A.; Merebashvili, Z. [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik; Koerner, J.G. [Mainz Univ. (Germany). Inst. fuer Physik; Rogal, M. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany)

2008-09-15

We calculate the next-to-next-to-leading order O({alpha}{sup 4}{sub s}) one-loop squared corrections to the production of heavy quark pairs in the gluon-gluon fusion process. Together with the previously derived results on the q anti q production channel the results of this paper complete the calculation of the oneloop squared contributions of the next-to-next-to-leading order O({alpha}{sup 4}{sub s}) radiative QCD corrections to the hadroproduction of heavy flavours. Our results, with the full mass dependence retained, are presented in a closed and very compact form, in dimensional regularization. (orig.)

Lead and Cadmium: Priorities for action from UNEP’s perspective for addressing risks posed by these two heavy metals

Directory of Open Access Journals (Sweden)

Piper D.

2013-04-01

Full Text Available The United Nations Environment Programme (UNEP has been focusing on actions with regard to lead and cadmium since 2001 when the work of the Partnership for Clean Fuels and Vehicles (PCFV was initiated. The development and finalization of the reviews of scientific information on lead and cadmium facilitated discussions among Governments in relation to the need for global action with regard to these heavy metals. UNEP continues to address priority areas for focusing to reduce risks posed by lead and cadmium. The Global Alliance to Eliminate Lead Paint (GAELP is a clear example for addressing those risks; however more work is expected to be done in relation to these key issues.

Heavy crude oil and synthetic crude market outlook

International Nuclear Information System (INIS)

Crandall, G.R.

1997-01-01

This presentation included an outline of the international heavy crude supply and demand versus Canadian heavy crude supply and disposition, and pricing outlook for synthetic crudes. Differences among crude oils such as light sweet, light sour, heavy and bitumen were described and illustrated with respect to their gravity, API, percentage of sulphur, metals and nitrogen. Internationally, heavy and sour crude supplies are forecast to increase significantly over the next four years. Discoveries of light sour crude in offshore Gulf of Mexico will provide a major new source of sour crude to U.S. Gulf Coast refineries. Venezuela's supplies of heavy and sour crude are also expected to increase over the next few years. Mexico and Canada have plans to increase their heavy crude production. All of the crudes will be aimed at the U.S. Gulf Coast and Midwest markets. Pentanes and condensates are also expected to increase based on the growing Canadian natural gas production. Diluent demand will also grow to match Canadian heavy crude/bitumen production. U.S. midwest refiners are proposing expansions to allow them to process more Canadian heavy crude oil. At present, only a few refineries are equipped to process significant amounts of synthetic crude. It was suggested that to absorb available heavy and synthetic production, increased penetration into both Canadian and U.S. markets will be required. Some refineries may have to be modified to process heavy and synthetic oil supplies. Heavy oil and synthetic producers may need to develop relationships with refiners such as joint ventures and term supply agreements to secure markets. 2 tabs., 12 figs

Heavy quark production and spectroscopy