7,662 research outputs found
Three-year performance of in-situ mass stabilised contaminated site soils using MgO-bearing binders
This paper provides physical and chemical performances of mass stabilised organic and inorganic contaminated site soils using a new group of MgO-bearing binders over 3 years and evaluated the time-dependent performance during the 3 years. This study took place at a contaminated site in Castleford, UK in 2011, where MgO, ground granulated blastfurnace slag (GGBS) and Portland cement (PC) were mixed with the contaminated soils in a dry form using the ALLU mass mixing equipment. Soil cores were retrieved 40-day, 1-year and 3-year after the treatment. The core quality, strength, and the leaching properties were determined via physical observation, unconfined compressive strength (UCS) and batch leaching tests. After 3-year treatment, the UCS values of ALLU mixes were in the range of 50–250 kPa; the leachate concentrations of Cd, Pb, Cu and Zn (except Ni) in all mixes were lower than their drinking water standards; and the leachability of total organics was in the range of 10–105 mg/L. No apparent degradation of the mass stabilised materials after 3 years’ exposure to the field conditions was found. MgO-GGBS blends were found able to provide higher strength and less leachability of contaminants compared to PC and MgO-only mixes in mass stabilised soils
Thermochemical properties of small oxygenated sulfur hydrocarbons and kinetics - reaction pathways of methylthiomethyl radical with oxygen
The thermochemical properties on CH3SCH2OOH and the corresponding two radicals resulting from loss of H atom: CH3SCH2OO and CH2SCH2OOH are important to understand the stability, reaction paths and kinetics of reactions of dimethyl sulfide and other sulfur hydrocarbons (sulfides) in the atmosphere and combustion processes. Thermochemical properties for species and transition states in the methylthiomethyl radical (CH3SCH2) + O2 reaction system are analyzed to evaluate reaction paths and kinetics under these conditions. Isodesmic working reaction are employed to determine the enthalpies of formation (ΔHf°298) using density functional (B3LYP/6-3 1 1G(d,p)) and complete basis set extrapolation (CBS-QB3) computational methods. Entropy (S°298) and heat capacities CP(T) ( 300≤T/K≤1500) are determined using geometric parameters and vibration frequencies obtained at B3LYP/6-3 11 G(d,p) level of calculation. Quantum Rice-Ramsperger-Kassel(QRRK) analysis is used to calculate energy- dependent rate constants, k(E) and master equation is used to account for collisional stabilization of adduct and isomer. The methyithiomethyl radical adds to oxygen to form a methylperoxy racial with a 37.82 kcal/mol well depth. The peroxy radical can undergo dissociation back to reactants, isomerize via hydrogen shift (TS1, Ea=17.06kcal/mol) to form a hydroperoxide methyl radical CH2SCH2OOH, decompose via hydrogen transfer (TS2, Ea=37.79kcal/mol) to form CH3SC(=O)H plus OH radical , or the peroxy radical can also attack the sulfur atom via TS3 (Ea=32.92kcal/mol) to form CH3S(=O) + CH2O. The CH2SCH2OOH isomer can decompose via TS4 (Ea=24.O9kcal/mol) to form CH2O+CH2S+OH, or through a four-member ring transition state (TS5, Ea= 30.77kcal/mol) to form 1,3-Oxathietane + OH.
Structures and thermochemical properties on Sulfenic Acids (RSOH R = CH3, CH3CH2, CH2=CH,) and their radicals are determined by CBS-QB3 calculation. Molecular structures and vibration frequencies are calculated at B3LYP/6-311G(d,p) levels. ΔHF°298, S°298 and C(T) for the concerned species are calculated in this study. Enthalpies of formation are determined using the ΔH°rxn(298) and known enthalpies in each of different working reactions. Contributions to entropy and heat capacity from internal rotation are also determined
Superactivation of monogamy relations for nonadditive quantum correlation measures
We investigate the general monogamy and polygamy relations satisfied by
quantum correlation measures. We show that there exist two real numbers
and such that for any quantum correlation measure ,
is monogamous if and polygamous if for a
given multipartite state . For , we show that the
monogamy relation can be superactivated by finite copies
of for nonadditive correlation measures. As a detailed example, we use
the negativity as the quantum correlation measure to illustrate such
superactivation of monogamy properties. A tighter monogamy relation is
presented at last
Monogamy relations of all quantum correlation measures for multipartite quantum systems
The monogamy relations of quantum correlation restrict the sharability of
quantum correlations in multipartite quantum states. We show that all measures
of quantum correlations satisfy some kind of monogamy relations for arbitrary
multipartite quantum states. Moreover, by introducing residual quantum
correlations, we present tighter monogamy inequalities that are better than all
the existing ones. In particular, for multi-qubit pure states, we also
establish new monogamous relations based on the concurrence and concurrence of
assistance under the partition of the first two qubits and the remaining ones.Comment: arXiv admin note: text overlap with arXiv:1206.4029 by other author
Polygamy relations of multipartite entanglement beyond qubits
We investigate the polygamy relations related to the concurrence of
assistance for any multipartite pure states. General polygamy inequalities
given by the th power of concurrence of
assistance is first presented for multipartite pure states in
arbitrary-dimensional quantum systems. We further show that the general
polygamy inequalities can even be improved to be tighter inequalities under
certain conditions on the assisted entanglement of bipartite subsystems. Based
on the improved polygamy relations, lower bound for distribution of bipartite
entanglement is provided in a multipartite system. Moreover, the th
() power of polygamy inequalities are obtained for the
entanglement of assistance as a by-product, which are shown to be tighter than
the existing ones. A detailed example is presented.Comment: arXiv admin note: text overlap with arXiv:1902.0744
Three-year performance of in-situ solidified/stabilised soil using novel MgO-bearing binders.
A new group of MgO-bearing binders has been developed recently which showed improved sustainability and technical performance compared to Portland cement (PC). However, the application of these MgO-bearing binders in the Solidification/Stabilisation (S/S) techniques is very limited. This study investigates the three-year performance of a highly contaminated soil treated by in-situ S/S using MgO-bearing binders and PC. The core quality, strength, permeability and the leaching properties of the S/S materials were evaluated. The effects of binder composition, addition of inorgano-organo-clay (IOC) and the grout content on the properties of the 3-y S/S materials are discussed. It is found that although MgO alone provided negligible strength to the soil, it is superior in immobilising both inorganic and organic contaminants. Replacing MgO by ground granulated blast-furnace slag (GGBS) significantly enhanced the strength while also performed well in immobilising the contaminants. The improved pH buffering capacity was attributed to the low solubilities of brucite and hydrotalcite-like phases formed in the MgO-bearing binders, and was also the reason for the improved performance in stabilising contaminants. The addition of IOC slightly decreased the strength and the permeability of the S/S materials but inconsistent effect on the contaminant immobilisation was found depending on the binder composition. This study showed no degradation of the S/S materials after 3 y exposure to field conditions and has proved the applicability and the advantages of MgO-bearing binders over PC in S/S.The authors are grateful to the funding from EPSRC (Grant No.: NMZJ/116 RG60240) to support this research. The samples were all retreived from a field trial sponsored by EPSRC/TSB (Grant No.: TP/5/CON/6/I/H0304E).This is the final version of the article. It first appeared from Elsevier via http://dx.doi.org/10.1016/j.chemosphere.2015.09.046 The data reported in this study can be accessed at: http://www.repository.cam.ac.uk/handle/1810/250325
Quantifying quantum coherence and non-classical correlation based on Hellinger distance
Quantum coherence and non-classical correlation are key features of quantum
world. Quantifying coherence and non-classical correlation are two key tasks in
quantum information theory. First, we present a bona fide measure of quantum
coherence by utilizing the Hellinger distance. This coherence measure is proven
to fulfill all the criteria of a well defined coherence measure, including the
strong monotonicity in the resource theories of quantum coherence. In terms of
this coherence measure, the distribution of quantum coherence in multipartite
systems is studied and a corresponding polygamy relation is proposed. Its
operational meanings and the relations between the generation of quantum
correlations and the coherence are also investigated. Moreover, we present
Hellinger distance-based measure of non-classical correlation, which not only
inherits the nice properties of the Hellinger distance including contractivity,
and but also shows a powerful analytic computability for a large class of
quantum states. We show that there is an explicit trade-off relation satisfied
by the quantum coherence and this non-classical correlation
Every Moment Counts: Dense Detailed Labeling of Actions in Complex Videos
Every moment counts in action recognition. A comprehensive understanding of
human activity in video requires labeling every frame according to the actions
occurring, placing multiple labels densely over a video sequence. To study this
problem we extend the existing THUMOS dataset and introduce MultiTHUMOS, a new
dataset of dense labels over unconstrained internet videos. Modeling multiple,
dense labels benefits from temporal relations within and across classes. We
define a novel variant of long short-term memory (LSTM) deep networks for
modeling these temporal relations via multiple input and output connections. We
show that this model improves action labeling accuracy and further enables
deeper understanding tasks ranging from structured retrieval to action
prediction.Comment: To appear in IJC
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