Miracle-dz/UniFAR-FTUs huggingface dataset:
A Hydroprocessing Multicatalyst Deactivation and Reactor Performance Model−Pilot-Plant Life Test Applications

A simple plug-flow model was developed to study the deactivation mechanisms of hydroprocessing catalysts in atmospheric residue desulfurization (ARDS) units. The three stages of catalyst deactivationat the start of the run, middle of the run, and end of the runare considered. The catalyst deactivation is mainly due to metal and coke deposition. The model parameters considered are the unit temperature, fluid velocity, reaction rate constant, catalyst combination, catalyst bed length, and feed concentration of sulfur, metals, and asphaltenes. The simulated results compared very well with our laboratory data for a long catalyst life test operated under constant-temperature mode. The model is further applied to a parametric study that examines the effects of space velocity, unit temperature, and maximum metal capacity on the performance of catalyst systems. A constant-sulfur-mode simulation is also given.
Propagation of 632.8 nm and 4.67 µm laser beams in a turbulent flow containing CO2 and H2O at high temperatures

Laser based missile defence systems (DIRCM) are being increasingly employed on aircraft. In certain circumstances the laser must pass through the exhaust gases of the aircraft engine. In order to predict the degree of divergence and dispersion of the laser, an understanding of the exhaust gas structure and its influence is required. Specifically the effect of parameters such as temperature, carbon dioxide, turbulence intensity and length scales as well as the laser beam wavelength and beam diameter. A parametric study under laboratory controlled conditions was undertaken to examine these effects. The results of beam propagation through high temperature turbulent flows and for various CO2 and H2O concentrations are presented in this paper for wavelengths 632.8 nm and 4.67 μm. It was found that the beam displacement showed an approximate inverse square relationship to temperature. At high combustion temperatures the 632.8 nm beam was significantly broken-up and dispersed. Displacement of both beams appeared to be asymptotic above 600°C. Carbon dioxide absorption effects were found not to significantly influence the beam displacement at the wavelengths and temperatures studied. Quantifying these effects at high temperatures will assist with the development of a parametrically based laser beam propagation model.
Micro free-flow electrophoresis with injection molded chips

In this work we present an approach towards economic free-flow electrophoresis chips fabricated by injection molding as mass replication process. This is achieved by the development of a free-flow electrophoresis chip design suitable for one step molding fabrication. Integrated partitioning bars are incorporated as key elements for bubble segregation. A defined open gap of 20 μm in height and 500 μm in width was integrated between the separation chamber and the electrode channels, acting as a barrier for gas bubbles while maintaining electrical contact by the fluidic junction. Additionally, we present an approach to avoid internal electrodes in FFE microchips for a facile mass production process. The injection molded thermoplastic μFFE chips are ready to use without subsequent labor-intensive implementation of membranes or comparable structures serving as salt bridges.
Molecular Simulations and Experimental Studies of CO2, CO, and N2 Adsorption in Metal−Organic Frameworks

Atomistic grand canonical Monte Carlo simulations were performed to understand the interplay of factors (pore size, heat of adsorption, open metal sites, electrostatics, and ligand functionalization) contributing to adsorption of CO2, CO, and N2 in MOFs. Four MOFs—IRMOF-1, IRMOF-3, Cu-BTC, and Zn2[bdc]2[dabco]—were chosen for comparison. Binary mixtures (CO2/CO) and (CO2/N2) containing 5%, 50%, and 95% CO2 were examined. CO2 is preferentially adsorbed over CO and N2 in all MOFs. Cu-BTC displays higher selectivities for CO2 over CO at lower pressures and CO2 over N2 at all pressures for all mixtures due to the increase in electrostatic interactions of CO2 with the exposed copper sites. However, IRMOF-3 shows surprisingly high selectivities for CO2 over CO for 50% and 95% mixtures at higher pressures due to the presence of amine-functionalized groups and high pore volume. CO2 selectivities increase with increasing CO2 concentration in the gas mixtures at total pressures above 5 bar. On the basis of the resu.
Tin monoxide as an s‐orbital‐based p‐type oxide semiconductor: Electronic structures and TFT application

Tin monoxide (SnO) is a stable p‐type oxide semiconductor. This paper reports electrical properties, electronic structures, and thin‐film transistors (TFTs) of SnO. Epitaxial films were fabricated by pulsed laser deposition. The Hall mobility and the hole density of the epitaxial films were 2.4 cm2 V−1 s−1 and 2.5 × 1017, respectively. X‐ray photoelectron spectroscopy (PES) indicated that the closed‐shell 5s2 orbitals of Sn2+ ions heavily contribute to the hole conduction path in SnO. Top gate type TFTs (W/L = 300/50 µm) employing 20 nm thick SnO channels exhibited field‐effect mobilities µsat = 0.7 cm2 V−1 s−1 and µlin = 1.3 cm2 V−1 s−1, which are larger by two orders of magnitude than those reported for p‐channel oxide TFTs to date. On/off current ratios were ∼102 and subthreshold voltage swings (S) ∼7 V/decade. The parameters required for TFT simulations were estimated by ultraviolet PES and first‐principles calculations. The TFT simulations indicated that subgap hole trap density in the SnO channel is >1019 cm−3, which limits the TFT mobilities and the S values.
Comparison of the Phosphorus Sorption Characteristics of a Conservation Reserve Buffer and an Adjacent Crop Field

The U.S. Department of Agriculture's Conservation Reserve Program (CRP) was established by the Food Security Act of 1985. Since its inception, thousands of acres of cropland in stream riparian zones have been converted to conservation buffers through the planting of trees and native grasses. The objectives of this study were to determine the phosphorus (P)–sorption characteristics of the surface soil in a 13‐year‐old CRP buffer and an adjacent continuously cropped production area from which the buffer was created and to assess differences in P‐sorption maxima and P‐buffering capacity between the sites. Phosphorus sorption was modeled with both the simple Langmuir and the two‐surface Langmuir equations. There were significant differences in all P‐sorption parameters between the cropped area and the buffer over most of the depth increments studied. The cropped area soil had higher sorption max (Smax), binding energy (k), and P equilibrium buffering capacity (PEBC) than the buffer soil. However, the buffer had higher equilibrium P concentration (EPC). These findings imply that it may not be appropriate to assume that a buffer will act as a P sink simply because it is not receiving P fertilization. Any assessment of buffer or filter strip effectiveness for P retention should include an examination of the P‐sorption properties of the soils present.
Isolation of cellulose nanocrystals from pseudostems of banana plants

On account of their excellent mechanical properties, cellulose nanocrystals (CNCs) are attracting significant interest as a naturally sourced, renewable and inexpensive component of a broad range of nanomaterials. CNCs can be extracted from virtually any natural cellulosic material, but characteristic properties such as maximum aspect ratio, crystal structure, and crystallinity vary considerably between sources. In this work, the isolation of CNCs from the pseudostems of banana plants was explored. The dried stems from the species musa sapientum linn were first cleaned by Soxhlet extraction, alkali treatment and bleaching and subsequently hydrolyzed to CNCs using sulfuric acid. The hydrolysis time was systematically varied, with the objective to maximize the length (L = 375 ± 100 nm) and aspect ratio (A = 28) of the resulting CNCs. The surface charge density of the CNCs thus isolated was 168 mmol kg−1, the predominant crystal structure was that of cellulose I, and the crystallinity was 74%. In order to elucidate the reinforcing capability of the new CNCs, nanocomposites with an ethylene oxide–epichlorohydrin copolymer were prepared and their mechanical properties were investigated by dynamic mechanical analysis (DMA). A comparison with reference nanocomposites made with CNCs isolated from cotton shows that the new CNCs display a higher reinforcing capability.
Evidence from EPR that nitroxide spin labels attached to human hemoglobin alter their conformation upon freezing

Human oxy-hemoglobin was spin labelled at the two β-93 cysteine positions with three different spin labels. Continuous wave electron paramagnetic resonance (CW EPR) was used to assess the dynamics of the attached spin labels in solution at room temperature. Solutions were frozen to 50 K and the distance between the spin labels was measured using the double electron electron resonance (DEER) pulsed EPR technique. The two sets of results were compared to the crystal structure of the protein and were found to be consistent with a model where the spin labels tend to adopt a less rigid surface exposed conformation in solution, but are positioned in a protein pocket in the frozen state.
Study on Storage Stability of SBS Modified Asphalt

Abstract The evaluation for the storage stability of SBS modified asphalt was made by adding selected inorganic stabilizers, which was reported in China and overseas. The experimental results showed that stabilizer A can improve the compatibility between base asphalt and SBS, the difference between bottom softening point and up softening point in the Isolate Test was about 0.2, which was much less than that of JTJ036–98 standard. So, the modification effect of stabilizer A on storage stability of SBS modified asphalt was the best. That is, in the period of storage and transportation, SBS and base asphalt did not isolate. Some defects were overcome during construction of an asphalt road surface. The adding stabilizer not only reduced the cost of production but also simply the procedure.
Determination of the molecular weight of proteins in solution from a single small-angle X-ray scattering measurement on a relative scale

This paper describes a new and simple method to determine the molecular weight of proteins in dilute solution, with an error smaller than ∼10%, by using the experimental data of a single small-angle X-ray scattering (SAXS) curve measured on a relative scale. This procedure does not require the measurement of SAXS intensity on an absolute scale and does not involve a comparison with another SAXS curve determined from a known standard protein. The proposed procedure can be applied to monodisperse systems of proteins in dilute solution, either in monomeric or multimeric state, and it has been successfully tested on SAXS data experimentally determined for proteins with known molecular weights. It is shown here that the molecular weights determined by this procedure deviate from the known values by less than 10% in each case and the average error for the test set of 21 proteins was 5.3%. Importantly, this method allows for an unambiguous determination of the multimeric state of proteins with known molecular weights.
X-ray fluorescence analysis in the Russian State Agrochemical Service: an overview

The advantages of x-ray spectrometry in the field of rapid non-destructive multi-element analysis of environmental samples have been well known since the 1950s. This was a reason to include this method in the system of analytical control of the Russian State Agrochemical Service (SAS) including regional centers and the Central Research Institute of Agrochemical Service (CINAO), and similar services all over the world. The SAS was organized by the Ministry of Agriculture of the former USSR more than 30 years ago in order to control the status of agricultural soils, quality of forage, plants, fertilizers and fertilizer management. In the previous stage (1980–90), x-ray spectrometry used all-vacuum simultaneous spectrometers for the quality control of forages all over the USSR in terms of macro and micro (trace) elemental composition. The program was terminated in the 1990s because of the high cost of operation, slow-operating apparatus and changes in Russia. However, the new edition of the Agricultural Ministerial Handbook with the regional distribution of mineral nutrients in plants was created owing to the results obtained. Since 1991, more adaptable and inexpensive portable instruments became available and investigations were focused on novel agroecological tasks, e.g. soil pollution with heavy metals. The adaptable and rapid method of soil analysis was evaluated and tested in an interlaboratory study organized by CINAO with the participation of Standard Committee institutes. Relatively good agreement of participant results was demonstrated and information about different kinds of uncertainties in x-ray fluorescence soil analysis with the use of portable instruments was obtained. This method became used as a standard of the Ministry of Agriculture of the Russian Federation for the rapid analysis of soils to determine the total content of Fe, Zn, Mn, Ni, Sr, Cr and Pb in laboratory and field conditions. Copyright © 2002 John Wiley & Sons, Ltd.
Colorimetry and its accuracy in the measurement of fluorescent materials by the two‐monochromator method

The fundamental procedure involved in the two-monochromator method for determining the spectral radiance factors of fluorescent materials is described, and some measured results are presented. The colorimetric accuracy of the method was confirmed by comparing two sets of tristimulus values: (1) those based on the two-monochromator method and calculated from the reflected and the fluorescent spectral radiance factors and the spectral power distributions of a tungsten-halogen lamp and a xenon lamp (which were determined separately); and (2) those calculated from the total radiance factors obtained from the measurement under polychromatic illumination, where the fluorescent materials were irradiated with the tungsten and the xenon lamp. The color differences between these sets of tristimulus values in CIE-LUV color space were estimated to be less than 1.0 unit, irrespective of the illuminant or the source.
Lidocaine for the prevention of pain due to injection of propofol.

Propofol has a high incidence of pain with injection, particularly into small veins. We sought to determine whether concomitant administration of lidocaine could prevent this pain. In a randomized doubleblind trial, 368 women were allocated to one of four groups to receive 19 mL of propofol mixed wi
Hollow-fibre liquid-phase microextraction of polychlorinated biphenyls: dynamic aspects and analytical challenges associated with their speciation

In the present article, the hollow-fibre liquid-phase microextraction of poly-chlorinated biphenyls (PCBs) was conducted under non-equilibrium conditions, to investigate the bioavailability of PCBs in natural waters. The study was conducted for 12 PCB congeners (log K ow ranging from 5.2 to 8.2) in the ng L−1 range. This appeared as a major challenge since aqueous solutions in this concentration range tend to evolve rapidly due to adsorption of PCBs on glass walls. The average aqueous diffusion layer was measured to be 43 ± 2 µm at 500 rpm. Aqueous diffusion coefficients of PCBs estimated from experimental data were found to be about two times lower than those predicted by the Hayduk-Laurie equation, possibly due to the underestimation of the molar volume of PCBs, the aggregation of PCBs in the aqueous phase, or a decrease of the actual aqueous concentration during the time of extraction. The presence of Aldrich humic acid (AHA) in the solution decreased, as expected, the mass transfer of PCBs to the fibre, but the flux was not linked either to the total or to the free PCB concentration. This suggests a semi-labile behaviour for the AHA–PCB complex, which was confirmed by the effect of stirring speed on the amount of PCBs extracted in the presence and in the absence of AHA. The whole of these observations suggests that diffusion in solution is not only one of the limiting process for the extraction of PCBs but also supports the need for more experimental data to understand in detail the mechanism of extraction of hydrophobic compounds, and their bioavailability in the presence of aquatic complexants.
Poly(amido‐amine)s: Biomedical Applications

Poly(amido-amine)s (PAAs) are synthetic tert-amino polymers obtained by stepwise polyaddition of primary or secondary aliphatic amines to bis(acrylamide)s. Linear polymers are produced during the polymerisation of both primary mono(amine)s and secondary bis(amine)s. Under non-selective conditions primary bis(amine)s usually give crosslinked products upon reaction with bis(acrylamide)s, i. e. , they react as tetrafunctional monomers. Furthermore, end-functionalised PAAs can be used to prepare block or graft copolymers, as well as crosslinked resins. PAAs can therefore be regarded as macromonomers as well. Generally, PAAs are soluble in water, chloroform, lower alcohols, dimethyl sulfoxide and other polar solvents (although amphoteric PAAs can only be dissolved in water). PAAs are degradable in aqueous solution by means of hydrolytic cleavage of the amidic bonds in their main chain that are activated by the tert-amino groups present in ? -position. A vast library of PAA structures has now been reported that are suitable for numerous material and biomedical applications. Here we review the synthesis, characterisation and current biomedical uses of PAAs. Their use as heavy-metal-ion-complexing polymers, and polymers for heparin neutralisation in solution, fabrication of heparin-absorbing resins and heparinisable materials is discussed. As amphoteric PAAs are biocompatible and biodegradable polymers that moreover display intelligent stealth properties, they are currently under development as PAA/anticancer conjugates and non-viral vectors for intracytoplasmic delivery. The potential of this unique chemistry is reviewed.
New High-flux Small-angle Neutron Scattering Instrumentation and the Center for Structural and Molecular Biology at Oak Ridge National Laboratory

A number of upgrades are currently being undertaken at the High Flux Isotope Reactor (HFIR), including the installation of a supercritical hydrogen moderator (T ∼ 20 K) that will be one of the brightest cold sources currently available. It will feed four cold neutron guides (CGI-4), each with new instrumentation. CG2 and CG3 are reserved for two new small-angle neutron scattering (SANS) instruments. A 40 m SANS instrument (SANSI), funded by the Department of Energy (DOE) Office of Basic Energy Sciences and the University of Tennessee, Knoxville is designed for CG2. Our 35 m small-angle neutron scattering facility (SANS2 on CG3) is optimized for the study of biological systems as part of a Center for Structural and Molecular Biology (CSMB), funded by the DOE Office of Biological and Environmental Research. In addition to the new SANS facilities, there will be suite of instruments including a reflectometer and a cold triple-axis spectrometer. Both SANS facilities will have variable wavelength and large area (1m2) high count-rate detectors that can translate 45 cm off axis to increase the dynamic Q-range ( 10 15 neutrons/s/cm 2 , the beam intensities (up to 10 7 /s/cm 2 ) will be comparable to the best facilities worldwide and this will enhance our ability to collect data from synthetic and biological macromolecules more quickly and study smaller sample quantities.
Quasiclassical Trajectory Dynamics Study of Atomic Oxygen Collisions on an O-Preadsorbed Graphite (0001) Surface with a New Analytical Potential Energy Surface

A new flexible periodic LEPS potential energy surface (FPLEPS) based on density functional theory data is constructed for the interaction of atomic oxygen with an O-preadsorbed graphite (0001) surface over a C–C bridge. New ingredients were added to the usual expression of the FPLEPS in order to take into account the entrance barriers, molecular orientation, and morphology of the surface. A total of 563 DFT points were used to fit the Eley–Rideal (ER) reaction channel, achieving a root-mean-square deviation of 0.120 eV for energies lower than 1 eV over reactants. A quasiclassical trajectory (QCT) dynamics study has been performed at several initial conditions: collision energies (0.01 ≤ Ecol ≤ 2.0 eV), incident angles (θv = 0°, 45°), and surface temperatures (100 ≤ Tsurf ≤ 900 K). Also quasithermal and hyperthermal (⟨Ecol⟩ = 5.2 eV) conditions were considered. Eley–Rideal reaction and O reflection were the main processes, keeping the formed O2 molecules translationally and internally excited via the ER pr.
Structural Thermodynamics of Hydration

A simple two-state structural model of solute hydration has been developed. In this model, both water in the bulk state and water of solute hydration are assumed to consist of two structural species: a high density/high enthalpy species, structurally similar to ice III, and a low density/low enthalpy species, structurally similar to ice I. It is assumed that structural and thermodynamic distinctions between bulk and hydration water originate solely from the differential fractional composition, whereas the two structural species and thermodynamic parameters associated with each species are identical for bulk and hydration water. This model has been used in conjunction with volumetric data reported in the literature to analyze the hydration properties of charged, polar, and nonpolar groups at 25 °C. The equilibrium between the two structural species of water of hydration of charged and polar groups is shifted toward the high density/high enthalpy species. In contrast, the equilibrium between the two specie.
Voltammetric Determination of Nitro Derivative of Synthetic Antioxidant 2,6-di-tert-butyl-4-methyl-phenol

ABSTRACT A new method is reported for the determination of the nitro derivative of the synthetic antioxidant 2,6-di-tert-butyl-4-methyl-phenol by differential pulse voltammetry with a hanging drop mercury electrode. Standard 2,6-di-tert-butyl-4-methyl-4-nitro-2,5-cyclohexadiene-1-one was synthesized for voltammetric determination after nitration. A nitration mechanism in acetic anhydride was proposed. The analyte provided a voltammetric signal in a mixture of 0.014 mole per liter potassium chloride and 94% ethanol. The developed method was employed for the determination of 2,6-di-tert-butyl-4-methyl-phenol in oil with satisfactory results, suggesting future application for practical analysis.
Impacts of fluorine on GaN high electron mobility transistors: Theoretical study

We investigate the role of fluorine (F) in GaN‐based high electron mobility transistors (HEMTs) with first principle calculations. Formation energy calculations of F in GaN and AlN reveal that energetically favored interstitial F (Fi) and substitutional F at N sites (FN) could play important roles in the performance of HEMTs. Fi is responsible for positive threshold voltage (Vth) shift by forming F– anion and depleting 2DEG carriers. The degradation of device performance at high temperature is ascribed to the defect energy state near conduction band edge of FN. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)