Miracle-dz/UniFAR-FTUs huggingface dataset:
SAFT- Force Field for the Simulation of Molecular Fluids 6. Binary and ternary mixtures comprising water, carbon dioxide, and n-alkanes

The SAFT-γ coarse graining methodology [E. A. Müller and G. Jackson, Ann. Rev. Chem. Biomol. Eng. 5, 405 (2014)] is used to develop force fields for the fluid-phase behaviour of binary and ternary mixtures comprising water, carbon dioxide, and n-alkanes. The effective intermolecular interactions between the coarse grained (CG) segments are directly related to macroscopic thermodynamic properties by means of the SAFT-γ equation of state for molecular segments represented with the Mie (generalized Lennard-Jones) intermolecular potential [V. Papaioannou, T. Lafitte, C. Avendaño, C. S. Adjiman, G. Jackson, E. A. Müller, and A. Galindo, J. Chem. Phys. 140, 054107 (2014)]. The unlike attractive interactions between the components of the mixtures are represented with a single adjustable parameter, which is shown to be transferable over a wide range of conditions. The SAFT-γ Mie CG force fields are used in molecular-dynamics simulations to predict the challenging vapour-liquid and liquid-liquid fluid-phase equilibria characterising these mixtures, and to study properties that are not accessible directly from the equation of state, such as the interfacial properties. The description of the fluid-phase equilibria and interfacial properties predicted with the SAFT-γ Mie force fields is in excellent with the corresponding experimental data, and of comparable if not superior quality to that reported for the more sophisticated atomistic or united-atom models.
Characteristics of partial discharges in artificial simulated tree channels during tree propagation

In order to clarify partial discharge (PD) mechanism in an electrical tree, we investigated PD pulse sequence and light emission from a single PD in an artificially-simulated tree channel during the tree propagation in low-density polyethylene (LDPE). For positive PD, the light emission was observed near the needle-tip and there was a positive correlation between the PD magnitude and the length of luminous region. The pulse-sequence analysis showed that PD took place at constant voltage increments. These results suggest that PD starts at the needle-tip and the PD magnitude is determined by the PD length. On the other hand, for negative PD, there was no correlation between the PD magnitude and the length of luminous region. The PD pulse sequence can be explained by a simple PD model, since the voltage increment is related to the magnitude of preceding PD. These results suggest that there is a difference between positive and negative PD characteristics and their mechanisms in an artificial channel during tree propagation.
Solution-Processable Nanowire Field-Effect Transistors

Solution-processable single-crystalline inorganic semiconducting nanowires are excellent building blocks for printable electronics requiring high performance of semiconducting components. Excellent charge carrier mobilities of crystalline nanowires combined with solvent-based nanowire processing open up possibilities for low-cost nanowire electronics targeting a variety of applications ranging from flexible circuits to chemical and biological sensors. Nanowire field-effect transistors are key devices for most of such applications. Recent developments in controllable nanowire positioning and orientation on the substrates and electrical property selection provide the necessary technological breakthroughs enabling the fabrications of reproducible nanowire transistors. In this chapter, we discuss the nanowire assembly methods and high-spatial-resolution scanning probe microscopy techniques towards scalable fabrication of high-performance printable nanowire field-effect transistors.
Perfluorooctanoic Acid (PFOA) and Perfluorooctane Sulfonate (PFOS) in Surface Water From the Langat River, Peninsular Malaysia

Perfluorinated compounds (PFCs) are not degradable and persistent compounds, bioacculumative and possess toxic characteristics. The compounds have been produced in large quantities and then applied and disposed without proper monitoring and regulation within the past half-century. Although the PFCs productions were to end today, the compounds would continue to persist in the environment for many years to come. Currently in Malaysia no studies have addressed perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) and no regulations has been developed to control these compounds. The analytical method used in this study involves solid phase extraction together with liquid chromatography coupled with mass spectrometry (LC/MS/MS). S# is referring to sampling station. Results from the water samples from Langat River, Malaysia, indicated that relatively high concentration of PFOS can be found in the eastern of the river, one of the most populated areas within the basin (S16–S35) with the highest concentration in station S35 (43.5 ng/mL). Reason for this concentration is that the compound was highly used in industry as well as in manufacturing processes and consumer products. Relatively high concentration of PFOA can be found in station S6 (5.94 ng/mL) because this station is the station receiving effluent from landfill site. Further studies on the PFCs compounds could provide more data set and larger view of current state of PFCs contamination in Malaysian aquatic environments.
Simulation of Protein Dynamics

Globular proteins exhibit a great variety of internal motions. One indication of this diversity is the range of characteristic times involved, which extends from 10-14 s for local vibrations to more than lcr s for certain structural transitions (1). Despite the obvious difficulties in dealing with such complicated systems, the dynamical richness of pro­ teins and the functional importance of their internal motions have attracted the interest of an increasing number of physical chemists in recent years (2-5). In particular, the experimental literature on protein dynamics has grown quite rapidly. Many different spectroscopic and kinetic techniques have been used to probe protein motions, in part because of the wide range of time scales involved. Several reviews of this work are now available (6-11). A small but increasing number of theoretical studies of protein dynamics have also appeared (11). Most of these studies are based on detailed computer models that can be used to simulate the classical dynamics of the atoms in a protein. As in the experimental work, it is necessary to use different theoretical techniques to study dynamical processes that occur on different time scales. The purposes of this review are to identify the different dynamical regimes of interest in proteins, to describe simulation techniques that may be useful for each regime, and to summarize the results of the various simulation studies. Before embarking on this program, it is useful to recall certain structural features of proteins.
Developing a 21st Century framework for lake‐specific eutrophication assessment using quantile regression

Over the past 30+ years, researchers and water resource managers have often relied on a set of regression‐based equations to describe the relationships between secchi depth (SD), chlorophyll (Chl) and total phosphorous (TP) and quantitatively assess lake trophic status after Carlson (1977). Here, we develop a revised framework for eutrophication assessment that incorporates recent statistical advances in ecology and leverages the increasing availability of lake‐specific datasets in the 21st Century. Long‐term (1992–2012) water quality data from Lake Champlain (LC) are used to revisit and revise classic equations of tropic state indices (TSIChl/TP). The upper boundaries of SD–ln(Chl) and ln(Chl)–ln(TP) distributions within this dataset fit well with quantile regression (99th, QR) to generate LC‐specific TSIChl/TP equations. Our results illustrate that Carlson (1977)'s original TSIChl/TP equations overestimate the trophic status of LC relative to LC‐specific equations, and highlight the power of the QR‐derived TSIChl/TP metric. We combine TSISD and TSIChl into one metric to indicate pseudoeutrophication and pseudomesotrophication of oligotrophic waters as well as pseudoeutrophication of mesotrophic waters to identify waters threatened by potential trophic shift. Additionally, TSIChl and TSITP were coupled as a complimentary dual metric to indicate potential risks of excessive phosphorus loading to oligotrophic and mesotrophic waters. With these dual metric schemes, we performed cluster analysis of 15 locations to spatially assess trophic status and phosphorous risks across LC. This study describes a relatively simple and robust approach for lake‐specific status assessment, the structure of which can be broadly utilized within monitoring and research communities.
Synthesis of tobermorite: A cement phase expected under repository conditions

In this study I have synthesized tobermorite, Ca{sub 5}Si{sub 6}O{sub l6}(OH){sub 2. }4H{sub 2}0, a principal crystalline phase expected to form in cementitious materials subjected to elevated temperatures in a potential nuclear waste repository. Fluids interacting with these materials may have a profound effect on the integrity of the waste package and on transport of radionuclides. At ambient temperature, Portland cement reacts with water to form an amorphous calcium-silicate-hydrate (C-S-H) gel. At elevated temperatures, crystalline phases of various hydration states form. The C-S-H system has not been well characterized at elevated temperatures up to 250{degrees}C, which has been considered a bounding temperature for the potential Yucca Mountain repository. Physical, chemical, and thermodynamic data for these cement minerals that are predicted to be stable at these temperatures must be obtained from synthetic or natural samples to help predict fluid chemistry. For some of these minerals natural samples are difficult to obtain in sufficient quantity and purity. Therefore, monomineralic phases must be synthesized in order to unambiguously define their behavior. The synthetic or natural phases will be characterized as part of a comprehensive study to define the behavior of cementitious materials in a repository environment.
Bond-order?bond-length?bond-strength (bond-OLS) correlation mechanism for the shape-and-size dependence of a nanosolid

A bond-order–bond-length–bond-strength (bond-OLS) correlation mechanism is presented for consistent insight into the origin of the shape-and-size dependence of a nanosolid, aiming to provide guidelines for designing nanomaterials with desired functions. It is proposed that the coordination number imperfection of an atom at a surface causes the remaining bonds of the lower-coordinated surface atom to relax spontaneously; as such, the bond energy rises (in absolute value). The bond energy rise contributes not only to the cohesive energy (ECoh) of the surface atom but also to the energy density in the relaxed region. ECoh relates to thermodynamic properties such as self-assembly, phase transition and thermal stability of a nanosolid. The binding energy density rise is responsible for the changes of the system Hamiltonian and related properties, such as the bandgap, core-level shift, phonon frequency and the dielectrics of a nanosolid of which the surface curvature and the portion of surface atoms vary with particle size. The bond-OLS premise, involving no assumptions or freely adjustable parameters, has led to consistency between predictions and experimental observations of a number of outstanding properties of nanosolids.
The Superposition of Thermal Activation in Dislocation Movement

The thermally activated movement of a dislocation intersecting a small density of strong point obstacles imbedded in a large density of weak obstacles is calculated analytically by modelling the geometrical correlations. The superposition of the flow stresses for the isolated processes is only valid for zero temperature. At high temperatures only the strong obstacles impede the movement wheras at low temperatures the weak obstacles contribute to or controll the flow stress. It is suggested that the plateau-stress in solid solutions has its origin in the dislocation forest which acts like strong obstacles. Die thermisch aktivierte Versetzungsbewegung uber starke Punkthindernisse mit kleiner Dichte, die in eine grose Dichte von schwachen Hindernissen eingebettet sind, wird mit einem Modell fur die geometrischen Korrelationen analytisch berechnet. Die Uberlagerung der Fliesspannungen fur die isolierten Prozesse gilt nur beim absoluten Nullpunkt. Bei hoher Temperatur wirken nur die starken Hindernisse, wahrend bei tiefen Temperaturen die schwachen Hindernisse zur Fliesspannung beitragen oder sie bestimmen. Es wird vorgeschlagen, das die Plateauspannung in Mischkristallen durch den Versetzungswald bedingt ist, der wie starke Hindernisse wirkt.
Structure and magnetic properties of polycrystalline Fe3O4 films deposited by reactive sputtering at room temperature

Polycrystalline Fe3O4 films have been prepared by reactive sputtering at room temperature, which is much lower than the reported temperature of above 500 K to deposit high quality Fe3O4 films. Transmission electron microscopy image shows that uniform Fe3O4 grains are well separated by grain boundaries and their size increases with film thickness. The magnetization of the Fe3O4 films measured at 300 K under 50 kOe magnetic field is much lower than the reported value of 471 emu/cc, which can be interpreted as the existence of strong antiferromagnetic coupling within the grain boundaries. The coupling between frozen surface spins and core spins and the switch of surface spin configurations cause hysteresis loop shift below 200 K and high field irreversibility, respectively. The observed decrease of magnetization with film thickness can be explained as the reduction in magnetization caused by the increased volume fraction of surface layer and the grain boundaries. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)
Detection of sibutramine and phenolphthalein in functional foods using capillary electrophoresis

A simple method has been established for the simultaneous detection of sibutramine and phenolphthalein by using capillary electrophoresis. A mixture of 20 mM phosphate buffer and 20 mM sodium dodecyl sulfate was used as running buffer (pH 11.0). Analysis was carried out at a detection wavelength of 223 nm under a separation voltage of 25 kV at 20 °C. The limits of detection (LODs) were 0.03 μg mL−1 for sibutramine and 0.18 μg mL−1 for phenolphthalein. The linear ranges of the method were 0.1–50 μg mL−1 for sibutramine and 0.8–50 μg mL−1 for phenolphthalein. The proposed method has been successfully applied for the detection of the two target chemicals in functional foods, with satisfactory recovery ranging from 95.3% to 103.4%.
On the Reliability of Calculated Log P-values: Rekker, Hansch/Leo and Suzuki Approach

A number of fragmental approaches for calculation of drug lipophilicity (log P) have been developed in recent years. Among these the procedures of Rekker, Hansch and Leo and that of Suzuki and Kudo offer good possibilities for setting up computerized versions of log-P calculation. This paper presents a comparative overview of the results of these three approaches for two series of hydrocarbon structures as well as for 36 selected drugs as tabulated by Rekker and Mannhold in their monograph “Calculation of Drug Lipophilicity”. The presented data demonstrate quite clearly that in a number of cases unexpected and unacceptable artefacts show up. Our final conclusion is that – at least for the series we chose for demonstration – the ultimate goal for faultless log P-calculations, although within reach, has not yet been fully realized.
Arsenic adsorption from contaminated water on Fe(III)‐coordinated amino‐functionalized poly(glycidylmethacrylate)‐grafted TiO2‐densified cellulose

BACKGROUND: The main aim of this study is to determine the sorptive potential of a novel anion exchanger, Fe(III)-coordinated amino-functionalized poly(glycidylmethacrylate)-grafted TiO2-densified cellulose (AM-Fe-PGDC) for arsenic(V) removal from aqueous solutions by batch technique. RESULTS: The adsorbent was characterized using infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, thermogravimetry and potentiometric titrations. The effective pH for removal was 6.0. The adsorption rate was influenced by initial metal ion concentration and contact time. The equilibrium was achieved within 1.5 h and follows a pseudo-second-order kinetic model. The adsorption capacity for As(V) calculated using the Langmuir isotherm equation was 105.47 mg g−1. The AM-Fe-PGDC developed was used to remove As(V) from simulated groundwater. Regeneration experiments were attempted for four cycles using 0.1 mol L−1 NaCl solution. CONCLUSION: It was found that AM-Fe-PGDC is very efficient for the removal of As(V) from aqueous solutions. © 2012 Society of Chemical Industry
Lead-free ferroelectric relaxor ceramics in the BaTiO3-BaZrO3-CaTiO3 system

Relative permittivity studies of ceramics with a variety of compositions in the BaTiO 3 -BaZrO 3 -CaTiO 3 system showed some of them to be ferroelectric relaxors at temperatures close to 295 K. Such a favourable effect is due to the Ca 2+ for Ba 2+ cationic substitution. In addition a spontaneous classical ferroelectric-relaxor ferroelectric transition was evidenced. Some of these new compositions are of interest for applications (dielectrics for capacitors, actuators) since they are environmentally friendly.
Optimization of Stepsize in X-Ray Powder Diffractogram Collection

Abstract Fourier transform methods of smoothing and interpolation are applied to X-ray diffraction data. It is shown that, frequently, too small a step size is used. Major gains are to be expected by selection of the optimum step size and use of these methods. A comparison of Fourier transforms of diffractograms of quartz measured between 67 and 69° 2θ, collected at varying step intervals (0.1 to 0.01° 2θ) was used to illustrate these applications. By examining the Fourier transform of the diffractogram and noting where it decays to die baseline, a reasonable estimate of the optimal step interval can be obtained. In addition, Fourier interpolation can be used to enhance the appearance of the diffractogram, approximating a continuous plot.
The arrangement of subunits in cholera toxin.

: Cholera toxin consists of five similar B subunits of apparent molecular weight about 10 600 and one A subunit (29 000) consisting of two peptides (A1 23 000-24 000 and A2 about 5500) linked by a single disulfide bond. Each B subunit also contains one internal disulfide bond which is readily reduced but is protected from carboxymethylation unless the reduced subunits are heated in urea. Tyrosine residues in A1 and in B subunits are readily iodinated, but the intact B assembly does not react with iodine. Upon reaction with the cross-linking reagent dimethyl suberimidate, B subunits may be covalently connected to each other, to A1 and to A2. A1 and A2 may also be cross-linked. The B subunits are probably arranged in a ring with A on the axis. A2 is required for the re-assembly of toxin from its subunits and may serve to hold A1 on the B ring. The maximum activity of cholera toxin in vitro is obtained only when the active peptide, A1, is separated from the rest of the molecule. Such separation, and the insertion of A1 into the cytosol, must follow the binding of the complete toxin, through component B, to the exterior of intact cells. This binding increases the effective concentration of the toxin in the vicinity of the plasma membrane. Possible ways in which A1 then crosses the membrane are considered in the Discussion.
Nitrate‐N and phosphate‐P concentration in winter wheat at varying growth stages(1)

Abstract Winter wheat triticum aestivum L. ) was sampled at selected stages of growth from N and P fertility experiments at one location in 1981 and three locations in 1982. Specific growth stages were determined using the Feekes scale. Plants were separated into roots, crowns, and leaves at each growth stage, dried, ground, and analyzed for NO3‐N and PO4‐P. Crown and leaf NO3‐N at growth stages 4 and 5 were significantly correlated with yield in 1981 at the Stillwater site. Crown and leaf NO3‐N and PO4‐P were also positively correlated with N and P applied at growth stages 4 and 5, respectively. In contrast to 1981, no moisture stress was present during 1982 and as such contributed to lower tissue concentration of NO3‐N and PO4‐P at all stages of growth. Limited positive correlation between independent crown and leaf PO4‐P and NO3‐N concentration at all growth stages with yield was found in 1982. However, surface response modeling using NO3‐N and PO4‐P in the leaf samples at or before stage 5 with yield p.
Gbbs free energies for interaction of CuCl 2 with (E)-1-phenyl-2- (2-(4-((E)-pheyldiazenyl) phenyl hydrazono)-2-(phenylsulfonyl) ethanone in ethanol at different temperatures.

--------------------------------------------------------ABSTRACT-------------------------------------------------the association constants, formation constants and Gibbs free energies of solvation are calculated from the conductometric titration curves of CuCl2 with (E)-1-phenyl-2-(2-(4-((E)henyldiazenyl)phenyl)hydrazono)2-(phenylsulfonyl)ethanone(L) in absolute ethanol at 293.15, 298.15, 303.15 and 308.15 K. On drawing the relation between molar conductance and the ratio of metal to ligand concentrations, different lines are obtained indicating the formation of 1:2, 1:1 and 2:1 (M:L) stoichiometric complexes. The formation constants and Gibbs free energies of these different complexes in absolute ethanol at 293.15, 298.15, 303.15 and 308.15 K follow the order: Kf (2:1) > Kf (1:1) > Kf(1:2) for (M:L); and ∆Gf (2:1)>∆Gf (1:1)>∆Gf (1:2) for (M:L).
Investigating the transfer processes across the free aqueous viscous boundary layer by the controlled flux method

Theory and experimental results of a new method are described directly investigating the transfer processes across the aqueous viscous boundary layer. The method is based on a known and controllable flux density being applied at the interface. Then the local transfer velocity can be determined by monitoring the tracer concentration at the water surface within minutes. Moreover, the time constant for the transport across the boundary layer (“surface renewal time”) can be measured directly. Comparison of the theoretical and measured frequency response of the boundary layer yields significant deviations. The technique is put into operation for heat transfer measurements. Direct comparisons with gas exchange measurements in several wind/wave facilities verify that the gas transfer velocity can be accurately extrapolated from the heat transfer measurements. A new way is opened both for detailed studies of the transfer processes in wind/wave facilities and the urgently needed direct parameterization of the transfer velocity as a function of windshear, wave parameters, and water turbulence in natural systems as rivers, lakes and the ocean. This paper includes (as a first example) measurements on the fetch dependency of the transfer process. DOI: 10.1111/j.1600-0889.1989. tb00135.x
Combined Effects of Salts and Temperature on the Thermal Destruction of Staphylococcus aureus MF‐31

The combined effects of salts (NaCl and KCl) and heat treatment temperature on the thermal destruction of Staphylococcus aureus MF-31 was studied by determining the relationships between the decimal reduction time (D value), temperature and each of three parameters (water activity, osmotic pressure and water binding energy) of the heating menstruum. The results demonstrated that the resistance of S. aureus MF-31 to heat destruction increased as the degree of salt-water association increased. Salts and heat treatment temperature had an interactive effect on heat resistance; however, increasing the heat treatment temperature made the difference caused by salt concentrations become insignificant.