Miracle-dz/UniFAR-FTUs huggingface dataset:
Thermal conductivity in two-dimensional monatomic non-linear lattices

The authors investigate the validity of Fourier's law in a two-dimensional monoatomic Toda lattice using the molecular dynamics method. The temperature profiles in the lattice exhibit an exponential behaviour with lattice position. The temperature dependence of thermal conductivity is necessarily derived from the spatial variation of the local temperature, and found to be inversely proportional to the local temperature. The validity of Fourier's law is confirmed by excluding the non-diffusive heat flow from the total heat currents.
Molecular dynamics of putrescine

Molecular dynamics simulations of the cationic polyamine putrescine have been performed at T= 300 K. Partial charges of putrescine were calculated with both the HF/STO-3G and HF/6-3G* methods. Solvent was represented either explicitly or via a distance-dependent dielectric of the form Iµ=r. Simulations were performed either with no counterions or with two chloride counterions present. In the case of the distance-dependent dielectric, two different sets of ionic parameters were used to model either hydrated or unhydrated ions. All possible combinations of partial charge set, ionic strength and type and solvent representation were simulated, giving ten different simulations. In general the putrescine molecule was found to adopt a number of different conformations that could be broadly characterised by the ranges in which the backbone torsion angles fell. The conformational behaviour of putrescine was found to be not strongly affected by the partial charges used or the hydration of the ions, however, it was significantly dependent on the representation of the solvent. With the distance-dependent dielectric, the putrescine favoured the ttt state at low ionic strength and the g+tt and g+tg± states at high ionic strength. When water molecules were explicitly included the ttt state was rarely adopted and the g+tg+ state was the most favoured, however, the g+tt state was also represented.
Antioxidant activity of different components of pine species

Abstract The total phenolic content and antioxidant activity of extracts from pine species were evaluated for various plant components, with emphasis on the seed cones. Seed cones from pine species were found to contain relatively high amounts of both total phenolics and antioxidant activity, and there appears to be some correlation of the two measurements. Juvenile cones contained by far the highest phenolic and antioxidant activity, but this high activity appears to be related to seeds retained in some of the samples, possibly due to the presence of proteins or additional antioxidants in the seeds. The phenolic content and antioxidant activity were also measured for other plant components and for a few other species for comparison. In general, the cones of red and jack pine exhibited the highest antioxidant activity compared to black and southern pines. The general trend for both total phenolics and antioxidant activity was (highest to lowest): juvenile cones>needles>new cones> bark>old cones>wood. Obviously, cones could represent a viable source of antioxidants, especially compared to the wood of species that had comparatively low activity. Collection and extraction of pine cones for antioxidants would be a non-destructive method for procurement of this medicinal aid.
Clear‐cutting of a Norway spruce stand: implications for controls on the dynamics of dissolved organic matter in the forest floor

Clear‐cutting of forest provides a unique opportunity to study the response of dynamic controls on dissolved organic matter. We examined differences in concentrations, fluxes and properties of dissolved organic matter from a control and a clear‐cut stand to reveal controlling factors on its dynamics. We measured dissolved organic C and N concentrations and fluxes in the Oi, Oe and Oa horizons of a Norway spruce stand and an adjacent clear‐cutting over 3 years. Aromaticity and complexity of organic molecules were determined by UV and fluorescence spectroscopy, and we measured δ13C ratios over 1 year.
Effect of moisture and temperature regimes on available phosphorus in wetland rice soils

Abstract A laboratory experiment was conducted to evaluate the effects of water and temperature regimes on availability of soil phosphorus (P). Four soil samples with variable levels of available P collected from a long‐term P frequency trial were incubated under two moisture regimes, continuous waterlogging (CWL) and alternate wetting and drying (AWD) at 20°C and 30°C temperature for 90 days. The samples were extracted with 0.5M NaHCO3 for available P determination after incubation. Increase in temperature increased available P content and this increase was more prominent in CWL conditions. Available P in all the soils tested was higher under CWL than AWD conditions, however, the increase in available P due to CWL environment was more pronounced in soils with higher available P.
CRC Handbook of Chemistry and Physics, 57th Edition

An entry of 0.0 for Δ f H ° for an element indicates the reference state of that element. See References 1 and 2 for further information on reference states. A blank means no value is available. The data are derived from the sources listed in the references, from other papers appearing in the Journal of Physical and Chemical Reference Data , and from the primary research literature. We are indebted to M. V. Korobov for providing data on fullerene compounds. References
Self-mutilating behaviors

Treating self-mutilating behaviors (SMB) is complex. Since people are continuing to engage in the behaviors, counselors need to be informed of the various techniques that are used with SMB as well as to be informed about common myths around selfmutilating behaviors. This paper will explore the methods of SMB, the common myths surrounding SMB, and the theories that explain and inform treatment of.
Electrochemical and binding properties of a novel ferrocene-containing redox-active basket-shaped host molecule

A novel basket-shaped host based on the rigid molecule diphenylglycoluril {3a,6a-diphenyltetrahydroimidazo[4,5-d]imidazole-2,5(1H,3H)-dione} has been synthesized and characterised. It is able to bind cations in its crown ether rings and neutral organic substrates in its cavity. Differential pulse voltammetry experiments showed that the host is redox-responsive to cations. It forms 1∶1 complexes with K+ and NH4+ ions and 1∶2 host–guest complexes with Na+ ions. On addition of (di)ammonium salts, protonation of the host occurs. A complex was formed between the host and model substrate olivetol (5-pentylbenzene-1,3-diol). In the absence of additives, this complex is stabilised via hydrogen bonds and π–π stacking interactions. In the presence of Na+ ions a complex consisting of the host, the diol, and 2 Na+ ions was formed, in which hydrogen bonds are no longer present. In the presence of 2 Na+ ions a four-fold increase in association constant has been found. Spectroscopic (NMR and IR) experiments have been used to elucidate the mode of co-operative co-ordination between the host, diol substrate and Na+ ions.
Fast Pyrolysis of Biomass in a Fluidized Bed Reactor: In Situ Filtering of the Vapors

A system to remove in situ char/ash from hot pyrolysis vapors has been developed and tested at the University of Twente. The system consists of a continuous fluidized bed reactor (0.7 kg/h) with immersed filters (wire mesh, pore size 5 μm) for extracting pyrolysis vapors. Integration of the filter system in the fluidized bed should overcome operational problems related to the increase in pressure drop across the filter in time and a decrease in oil yield as typically observed in downstream pyrolysis vapor filtration and lead to process intensification. In this study the effect of in situ hot pyrolysis vapor filtration has been studied with respect to process stability, product yields, and product quality. Oil obtained via a more conventional cyclone system placed in parallel to the filter system served as reference for the quality and yields of the filtered oil. Good process stability concerning temperature and pressure drop across the hot gas vapor filter was achieved during a 2 h run, even when using a reused filter. Particles (char/sand) were retained inside the filter pores located at the outside surface of the filter, while the inside of the filter remained clean apart from some deposits formed on the metal wire and small 1 μm particles which slipped through the filter. Mass balance closures higher than 94 wt % were obtained. Comparable yields (cyclone + filtered oil) were obtained as in the experiments carried out with only the cyclones. The filtered oil contained significantly less solids, alkali metals, and ash compared to cyclone oil. For the alkali metals, only a considerable amount of potassium (K) was still present in filtered pyrolysis oil, which most likely entered the filtered oil via the vapor phase. There were no significant differences in the elemental composition of the oil produced via the filter line and cyclone line. The molecular weight of the filtered oil obtained with nondried feed was always marginally lower compared to the cyclone oil. Results of the aging tests show that the reactivity of pyrolysis oil can already originate from the highly reactive components in pyrolysis oil itself and does not need the presence of char/ash. To show the intrinsically high reactivity of solids-free pyrolysis oil vapors, an external filter section (1 μm pore size) was placed additionally and in series with the filter inside the fluidized bed. The results show that char is formed from the reactive pyrolysis vapors.
Seasonal Variability of Particle-Associated Organic Compounds Near a Heavily Traveled Secondary Road

Size-resolved aerosol samples were collected both upwind and downwind of a large secondary road in the winter and spring of 2007 to assess contributions of on-road emissions to ambient aerosols. The aerosol samples were extracted and analyzed for a wide variety of organic compounds including polycyclic aromatic hydrocarbons (PAHs), alkanes, sugars, and organic acids. The results showed a strong seasonal pattern where the concentrations of most compounds were higher in winter than in spring. Some of the biogenic sugars were the exception, which might be the result of a “spring blooming season. ” The surprising result was that the upwind site located in a residential neighborhood had very similar concentrations of most organic compounds compared to the near-roadway site. Possible reasons for the lack of differences in organic chemical concentrations between the near-road and control sites include: a large urban background concentration of aerosols superimposed on any local source; shifting wind directions that make the “downwind” site upwind during the night; and additional local sources in the residential neighborhood such as wood burning in winter. Copyright 2014 American Association for Aerosol Research
Numerical study of combustion initiation in a supersonic flow of H2–air mixture by resonance laser radiation

A comparative analysis of the efficiency of approaches based on the exposure of reacting gas to resonance laser radiation to enhance combustion in a supersonic flow of H2–air mixture is conducted. The kinetic processes responsible for the intensification of chain reactions in premixed and non-premixed H2–air flows upon photodissociation of O2 molecules by 193.3 nm laser radiation, excitation of these molecules to the singlet sigma state by laser photons with 762.346 nm wavelength and heating the mixture by laser radiation are analysed in a detailed manner. It is shown that both photochemical methods, photodissociation and excitation of O2 molecules, are much more effective in shortening the ignition delay length than merely heating the mixture. For the premixed flow, the photodissociation of O2 molecules ensures a slightly higher reduction in the ignition delay than the laser-induced excitation of molecular oxygen to the singlet sigma state. However, in the non-premixed flow the situation is inverted. The analysis shows that both photochemical methods make it possible to raise the efficiency of conversion of reactant chemical energy to thermal energy released during combustion compared with the method of heating the mixtures.
Computational Exploration of Newly Synthesized Zirconium Metal-Organic Frameworks UiO-66, 67, 68 and Analogues

One of the major weaknesses of metal–organic framework (MOF) materials is their rather low thermal, hydrothermal, and chemical stabilities. Identification of stable and solvent resistant MOF materials will be key to their real world utilization. Recently, Lillerud and coworkers reported the synthesis of a new class of Zr MOF materials. These materials have very high surface area and exceptional thermal stability, are resistant to water and some solvents, acids, bases, and remain crystalline at high pressure. The newly synthesized Zr metal–organic frameworks (UiO-66, -67, and -68) as well as analogues substituting Ti and Hf for Zr, are explored using density functional theory calculations. The crystal structure, phase stability, bulk modulus, electronic structure, formation enthalpies, powder X-ray diffraction, chemical bonding, and optical properties are studied. We find bulk moduli of 36.6, 22.1, and 14.8 GPa for UiO-66, -67, and -68 respectively. As the linkers are extended, the bulk modulus drops. The highest occupied crystal orbital to lowest unoccupied crystal orbital gaps range from 2.9 to 4.1 eV. The compounds have similar electronic structure properties. Experimental powder X-ray diffraction patterns compare well with simulation. The large formation enthalpies (−40 to −90 kJ mol−1) for the series indicate high stability. This is consistent with the fact that these materials have very high decomposition temperatures. A detailed analysis of chemical bonding is carried out. Potential applications for these new materials include organic semiconducting devices such as field-effect transistors, solar cells, and organic light-emitting devices. We hope that the present study will stimulate research on UiO-based photocatalysis and will open new perspectives for the development of photocatalysts for water splitting and CO2 reduction. The large surface areas also make these materials good candidates for gas adsorption, storage, and separation.
Novel DABCO Based Ionic Liquids: Green and Efficient Catalysts with Dual Catalytic Roles for Aqueous Knoevenagel Condensation

Four novel basic ionic liquids (ILs), based on 1,4-diazobicyclo[2.2. 2]octane (DABCO) and 3-chloro-1,2-propanediol, have been introduced as catalysts for Knoevenagel condensation. These catalysts are applicable to a wide range of aromatic/heteroaromatic aldehydes with α-aromatic (heteroaromatic or polyaromatic)-substituted methylene compounds in water at room temperature, and they afford the products in excellent yields within short times. These reactions are operationally simple, and the desired products can be separated directly from the reaction mixture without further purification. A possible reaction mechanism was proposed, and the relevant evidence was given. In addition, the ionic liquids used can be regenerated and recycled several times without significant loss of activity. Furthermore, the novel ILs could be efficiently used in a step of atorvastatin synthesis.
High sensitivity microwave characterization of organic molecule solutions of nanoliter volume

A microwave resonator composed of a sapphire cylinder and a quartz plate with a 400 nl cavity was developed for the determination of the complex permittivity of liquids at 10 GHz. This sensor was calibrated over a wide range of values for real and imaginary parts of permittivity. The measured resonator losses induced by the liquid were found to be proportional to the dipole relaxation time of the liquid molecules, as predicted by perturbation theory. Our analysis of weight concentration and temperature dependence of the measured inverse quality factor revealed a sensitivity of about 0.1% for aqueous solutions of glucose.
Growth Deceleration of Vertically Aligned Carbon Nanotube Arrays: Catalyst Deactivation or Feedstock Diffusion Controlled?

Feedstock and byproduct diffusion in the root growth of aligned carbon nanotube arrays is discussed. A non-dimensional modulus is proposed to differentiate catalyst-poisoning controlled growth deceleration from one which is diffusion controlled. It is found that, at the current stage, aligned multiwalled carbon nanotube arrays are usually free of feedstock diffusion resistance while single-walled carbon nanotube arrays are already suffering from a strong diffusion resistance. The method presented here is also able to predict the critical lengths in different CVD processes from which carbon nanotube arrays begin to meet strong diffusion resistance, as well as the possible solutions to this diffusion caused growth deceleration.
Generalization of Turbulent Swirl Flame Transfer Functions in Gas Turbine Combustors

Experimental investigations of the forced response of swirl-stabilized turbulent flames to upstream flow disturbances were performed in an industrial scale gas turbine combustor operating with natural gas fuel and CO2/air. We measured flame transfer functions (FTFs) for a wide range of forcing frequency over a broad range of operating conditions with 50–120 kW thermal power. A sensitivity analysis was then performed in order to identify the key dimensionless parameters controlling the forced swirl flame dynamics. Two different dimensionless parameters, S t 1 = (fδ sw )/U and S t 2 = (f L f )/U, are used as dimensionless frequencies, while the dependence of the FTF gain on the turbulent flame speed is taken into account using a dimensionless flame length, ξ = L f /D c . The implementation of the nondimensionalization strategy using several time and length scales reveals that all FTFs are well characterized by either S t 1 or S t 2, but the best result is obtained from a combination of S t 1 and S t 2, which accounts for the interference mechanisms of vortical and acoustic disturbances in the system. As a consequence, the occurrence of local minima and local maxima, a clear manifestation of destructive and constructive interferences of acoustically forced swirl-stabilized flames, is well captured by the dimensionless numbers. This methodology is then applied to extensive FTF data measured from a different gas turbine combustor. A comparison of the FTFs for the two different gas turbine combustion systems provides insight into generalized transfer function behaviors in the dimensionless domain. This study focuses on velocity-coupled combustion instability, and these generalizations may not extend to situations where other coupling mechanisms dominate.
The soil solution in a soil treated with digested sewage sludge

SUMMARY Toxic trace metals may percolate to the ground water from sewage sludge disposed onto land. Analyses are presented of the soil solution from a slightly acid loamy soil treated 7 years earlier with single applications of digested sewage sludge in amounts equivalent to 0, 150 & 330 t dry matter ha−1 These very heavy dressings correspond to 2 & 4.5 times the recommended 30–year limit. Samples of soil and soil solution from four depths to 80 cm were analysed for Al, B, Ba, Ca, Cl, Cu, Fe, K, Li, Mg, Mn, Na, Ni, P, S, Sr, V, Zn, together with the OM of the soil, and the pH, alkalinity, dissolved organic carbon, and absorbance at 350 nm of the solutions. These very heavy sludge applications were apparently still releasing substantial quantities of NO3, and some SO4 even after 7 years. Nitrate, SO4, Mg, Ca, Sr, B, and possibly Ba are still moving through the profile, possibly to the ground water. Solution concentrations of Cu and Zn are considerably higher at all depths than those in the untreated plot, but they fall off sharply with depth. It is unlikely that any Cu or Zn is now reaching the ground water. The paper also presents a set of published solution analyses for soils, sludge–treated soils and digested sludge, as a basis for further studies.
Resonant microwave power absorption in slabs and cylinders

Resonant power absorption is an important phenomenon during microwave heating. The resonances that occur when plane electromagnetic waves are incident on infinitely long cylinders and slabs are investigated as a function of sample dimensions. For cylinders two kinds of incident waves are studied: $TM^z$ when the electric field is oriented along the axis of the cylinder and $TM^z$ when the magnetic field is oriented along the axis. At a resonant condition the overage power absorbed by the sample is a local maximum. Due to attenuation within the sample the resonances decrease in intensity as the sample size increases. Using the dielectric properties of water, resonances are found to be a function of the ratio of the sample dimension to the wavelength of radiation, $\lambda_s$, in the sample. For slabs of thickness L and integer values of n, resonances occurred at $L/\lambda_s = 0.5n$; for cylinders of diameter D, resonances occurred at $D/\lambda_s = 0.5n - 0.257$. The generality of these relations to predict resonances in other food samples are shown using existing dielectric data. Resonances in cylinders for both polarizations occurred at similar radii. However, the radius at which the first resonance occurred for the $TM^z$ case was absent in the $TM^z$ case.
Effect of aerial oxidation pretreatment on composition and effectiveness of a Nigerian lignite sample as soil organic matter amendment.

Abstract A Nigerian lignite sample was analyzed for its nutrient element and organic components. The effect of two oxidation procedures, namely, oven‐oxidation and wet‐oxidation on the composition and extractability of organic fraction with 0.1 M sodium hydroxide (NaOH), was also studied. A pot experiment was conducted to investigate effect of the oxidized lignite samples on the growth of Gmelina arborea seedlings. The lignite sample is very acidic in reaction with a pH of 2.0, and has low quantity of macro‐ and micronutrient elements with a carbon (C):nitrogen (N) ratio of 103. It, however, has over 90% organic matter with more than 78% extractable humic substances. All these components were either increased, decreased, or unaffected by the oxidation pretreatments. Compared to the control, both the unoxidized and differently oxidized lignite samples, generally depressed growth of 12‐week‐old Gmelina arborea seedlings in the Alfisols while their addition to the Oxisols enhanced the growth of the seedlings.
Computer simulation studies of anisotropic systems. XXVI. Monte Carlo investigations of a Gay–Berne discotic at constant pressure

The majority of molecules which form liquid crystals are elongated in shape. However, disk shaped molecules have also been shown to exhibit liquid crystalline phases. In this paper we report a series of constant pressure Monte Carlo simulations of model discotic molecules. We have used the Gay–Berne potential, which is in essence an anisotropic version of a shifted Lennard‐Jones potential, to model the interactions between the disks. Initially we studied a system of 512 molecules over a range of pressures to determine the mesophases formed and to construct the phase diagram. The system was found to exhibit isotropic, nematic, and columnar phases. We have also studied a larger system of 2000 molecules at a single pressure to calculate more accurately the distribution functions used to describe the translational and orientational order within the various phases.