Miracle-dz/UniFAR-FTUs huggingface dataset:
Thermal Degradation and Decomposition Products of Electronic Boards Containing BFRs

Production of electronic boards containing brominated flame retardants is constantly increasing, posing important problems with disposal of products containing these materials. The present study investigated the thermal degradation behavior of electronic boards manufactured using tetrabromobisphenol A and diglycidyl ether of bisphenol A epoxy resins. Qualitative and quantitative information was obtained on the products formed in the thermal degradation process, and the bromine distribution in the different product fractions was determined. The more important decomposition products included hydrogen bromide, phenol, polybrominated phenols, and polybrominated bisphenol A species. The formation of considerable amounts of hydrogen bromide and high-molecular-weight organobrominated compounds, as well as the potential formation of limited quantities of polybrominated dibenzo-p-dioxins and dibenzofurans, is an important element of concern in the safety and environmental assessment of the thermal degradation proc.
A Free Energy Model for Confined Diblock Copolymers

In this paper, the treatment of Turner is extended to include the possibility of a vertical orientation of the lamellar morphology. A free energy model is constructed for confined diblock copolymers organized normal to the walls and compared to the symmetric and antisymmetric horizontal cases. The vertical orientation is shown to be favored over both horizontal structures in a limited range of film thicknesses that depends on the material parameters of the confined structure.
Development and Validation of RP-HPLC Method for the Estimation of Raloxifene in Marketed Formulations

Abstract A Simple, selective, accurate, economical reverse phase high performance liquid chromatography (RP-HPLC) was developed for estimation of Raloxifene in pharmaceutical formulations. Chromatographic separation achieved on a C18column (Use INERTSIL, C18, 5μ, 250 × 4.6 mm i.d.) with mobile phase containing acetonirile and ammonium acetate buffer in the ratio 75:25 v/v. The flow rate was 1.0 mL/min and effluent was monitored at 254 nm. The retention time was 4.413 min. The method was validated in terms of linearity, accuracy and precision. The linearity curve was found to be linear over 2.5 —12.5 μg/mL. The limit of detection and limit of quantification were found to be 0.0202 and 0.202 μg/ml respectively. The proposed method was successfully used to determine the drug content of marketed formulations.
Gas hold-up and solids hold-up in flotation columns: on-line measurement based on electrical conductivity

Abstract Electrical conductivity measurements in solid-liquid and solid-liquid-gas dispersions have proven suitable for determination of the volumetric fraction of the phases, or hold-up. A combination of estimation routines was applied to determine the gas hold-up and solids hold-up on line in a flotation column. Gas holdup was determined by using the so-called 'phase separation method' and the standard addition method was used to estimate solids hold-up. Laboratory results validating the techniques and results obtained from applications in industrial flotation columns are presented.
Matrix-assisted Laser Desorption/Ionization Mass Spectrometry of Natural and Synthetic Lignin

Lignin is one of the components, with cellulose and hemicellulose, of cell walls in all terrestrial plants. Lignin is an amorphous, three-dimensional, polyphenolic molecule charged with the function of giving strength and impermeability to the plant structure. The determination of its molecular weight and structure is still problematic owing to the difficulties in isolation of lignin from the other cell wall constituents. The present work reports the experimental conditions for matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the characterization of different types of natural lignins and of one synthetic lignin. A nitrogen laser (λ=337 nm) was used for ion desorption and sinapinic acid (3,5-dimethoxy-4-hydroxycinnamic acid) was chosen as the best matrix for lignin analysis. Data on the molecular weight distribution of oligomers in lignin and information on the monomeric constituents of different types of lignin are shown.
Modeling Ignition in Catalytic Microreactors

A pseudo-2D reactor model is used to perform a comprehensive study on the catalytic ignition of a lean propane/air mixture in a microreactor with Pt-coated walls. The results of the in-house code are verified against the commercial package FLUENT. The roles of inlet velocity, wall conductivity, heat losses or heat transfer to an adjacent endothermic channel, channel gap size, and wall thickness in steady-state ignition via inlet preheating and resistive heating, are studied. The results show that the heat loss/transfer has the largest effect on ignition for both ignition modes. For an adiabatic reactor, the ignition inlet temperature decreases with increasing wall conductivity. The exact opposite trend is observed at high heat losses. On the other hand, in the resistive heating mode, the external power input at ignition decreases with increasing wall conductivity, irrespective of the heat losses. Lower values of the inlet velocity result in a lower required power input for ignition. The two ignition modes are contrasted, and microreactor and multifunctional devices start-up strategies are suggested.
Electrooptical behavior of liquid-crystalline (hydroxypropyl)cellulose/ inorganic salt aqueous solutions

The selective light reflection and turbidimetric property of concentrated aqueous solutions of (hydroxypropyl)cellulose (HPC), originating from their cholesteric mesophase structure and LCST-type phase behavior, respectively, are much affected by coexistence of inorganic salts therein. This is ascribed to a strong dependence of both cholesteric helical pitch (P) and cloud point (Tc) of the aqueous cellulosic solutions on the sort and concentration of the additive salts. By virtue of electrophoretic motility of the coexistent salt ions as P and/or Tc shifter, the dynamic variation in cholesteric coloration and/or optical turbidity of the HPC solutions was realized under the action of a relatively weak electromotive force to electrodes in contact with their layered sample. It was reasonably taken that the electrical stimulation allowed the ion particles to migrate and localize in this lyotropic system, resulting in occurrence of a certain degree of gradient in magnitude of P and/or Tc in response to the une.
A New Look at the 5á-Reductase Inhibitor Finasteride

Finasteride is the first 5a-reductase inhibitor that received clinical approval for the treatment of human benign prostatic hyperplasia (BPH) and androgenetic alopecia (male pattern hair loss). These clinical applications are based on the ability of finasteride to inhibit the Type II isoform of the 5a-reductase enzyme, which is the predominant form in human prostate and hair follicles, and the concomitant reduction of testosterone to dihydrotestosterone (DHT). In addition to catalyzing the rate-limiting step in the reduction of testosterone, both isoforms of the 5a-reductase enzyme are responsible for the reduction of progesterone and deoxycorticosterone to dihydroprogesterone (DHP) and dihydrodeoxycorticosterone (DHDOC), respectively. Recent preclinical data indicate that the subsequent 3a-reduction of DHT, DHP and DHDOC produces steroid metabolites with rapid non-genomic effects on brain function and behavior, primarily via an enhancement of a-aminobutyric acid (GABA)ergic inhibitory neurotransmission. Consistent with their ability to enhance the action of GABA at GABA A receptors, these steroid derivatives (termed neuroactive steroids) possess anticonvulsant, antidepressant and anxiolytic effects in addition to altering aspects of sexual- and alcohol-related behaviors. Thus, finasteride, which inhibits both isoforms of 5a-reductase in rodents, has been used as a tool to manipulate neuroactive steroid levels and determine the impact on behavior. Results of some preclinical studies and clinical observations with finasteride are described in this review article. The data suggest that endogenous neuroactive steroid levels may be inversely re
A first-principles simulation of the semiconductor/water interface

The overall electronic structure of a water/semiconductor interface is studied for the first time by ab initio molecular dynamics for realistic solvent configurations. The present study expands on our earlier work [J. Chem. Phys. 103, 7569 (1996)] by including a complete ab initio description of the surface and the solvent. Several statistically independent solvent configurations are generated via classical molecular dynamics as a starting point for a realistic sampling of the true solvent electronic structure via ab initio dynamics. A significant degree of mixing is observed between semiconductor electronic surface states and the bulk water orbitals. A new method is also given to facilitate the use of gradient corrected density functionals with Vanderbilt pseudopotentials.
Modelling X-ray or neutron scattering spectra of lyotropic lamellar phases : interplay between form and structure factors

The lamellar phase of two binary systems, AOT/water and DDAB/water, is studied by X-ray or neutron scattering techniques, along dilution lines. We observe on both systems a large wave vector diffuse scattering with the following features : i) its shape is independent of dilution ; ii) its intensity scales linearly with the bilayer volume fraction ; iii) it is sensitive to the scattering length density profile of the amphiphilic bilayer. With the help of a model combining geometry of the bilayers and layer displacement fluctuations, we quantitatively describe our data. This allows us to ascribe the diffuse scattering to the strongly enhanced thermal diffuse scattering which originates in the Landau-Peierls instability characteristic of the smectic A symmetry of our systems. The model has two important consequences : i) the form factor of the amphiphilic bilayer may be extracted from the large wave vector diffuse scattering ; ii) the Bragg peak intensities, modulated by the bilayer form factor, also depend on the amplitude of the thermally-excited elastic waves, i.e. on the magnitude of the elastic constants.
POWD, an interactive program for powder diffraction data interpretation and indexing

An interactive program, POWD, written in Fortran77, for powder diffraction data interpretation and indexing is described. Various functions such as the least-squares refinement and the systematic absence test are also included in this versatile program. The modified de Wolff figure of merit [Wu (1988). J. Appl. Cryst. 21, 530–535] is introduced in the program to decrease the execution time and estimate the reliability of the indexing. Very high success rates for indexing and tolerance of the presence of limited impurity lines are demonstrated by testing the program on several groups of powder data.
Dynamic Surface Processes of Nanostructured Pd2Ga Catalysts Derived from Hydrotalcite-Like Precursors

The stability of the surface termination of intermetallic Pd2Ga nanoparticles and its effect on the hydrogenation of acetylene was investigated. For this purpose, a precursor synthesis approach was applied to synthesize supported intermetallic Pd2Ga nanoparticles. A series of Pd-substituted MgGa-hydrotalcite (HT)-like compounds with different Pd loading was prepared by coprecipitation and studied in terms of loading, phase formation, stability and catalytic performance in the selective hydrogenation of acetylene. Higher Pd loadings than 1 mol % revealed an incomplete incorporation of Pd into the HT lattice, as evidenced by XANES and TPR measurements. Upon thermal reduction in hydrogen, Pd2Ga nanoparticles were obtained with particle sizes varying with the Pd loading, from 2 nm to 6 nm. The formation of intermetallic Pd2Ga nanoparticles led to a change of the CO adsorption properties as was evidenced by IR spectroscopy. Dynamic changes of the surface were noticed at longer exposure times to CO and higher c.
Liquid mixtures for matrix-assisted laser desorption

Binary matrix solutions are described which can be used for matrix-assisted laser desorption of peptides and proteins at 532 or 337 nm. The matrix solutions are composed of a strongly absorbing organic compound, such as rhodamine 6G or 1,4-diphenyl-1,3-butadiene, dissolved into a polar liquid, such as 3-nitrobenzyl alcohol or glycerol. Variations in absorber concentration are shown to affect the mass resolution, with higher resolution mass spectra being obtained at lower absorber concentrations. At the lowest absorber concentrations, mass resolution approaches that obtained with this instrument using the standard solid matrix, sinapinic acid
Soil Phosphorus Extracted by Bray 1 and Mehlich 3 Soil Tests as Affected by the Soil/Solution Ratio in Mollisols

Different relationships between soil-test methods results have been reported in several agricultural regions. Differences in the same soil-test procedure (e.g., soil/solution ratio) exist between soil-testing laboratories from different agricultural regions. Our objectives were to (1) determine the effect of soil/solution ratio on the amount of phosphorus removed by Bray 1 and Mehlich 3 methods, (2) compare the amounts of phosphorus removed by Bray 1 and Mehlich 3 in Mollisols from the Pampean region, and (3) determine whether soil/solution ratio affects the relationship between Bray 1 and Mehlich 3. Soil phosphorus availability was determined with two extractants (Bray 1 and Mehlich 3), using two soil/solution ratios (1:10 and 1:8, wt/v) in 72 soils (noncalcareous, loess-derived Molisolls) from the Pampean region. The amount of phosphorus removed was 20–24% greater when using 1:10 than 1:8 (wt/v) soil/solution ratio. This effect was significantly greater in Bray 1 than in Mehlich 3 (p = 0.04). When compared using the same soil/solution ratio, Mehlich 3 removed 4 to 8% more phosphorus than Bray 1. The soil/solution ratio used in the comparison affected the relationship between both extractants. The difference between extractants was slightly greater with a soil/solution ratio of 1:8 than of 1:10 (p = 0.03). Our results showed that even when using the same method, changes in the procedure (like soil/solution ratio) may cause different soil-test results and also differences in the relationship between two extracting solutions. Therefore, reported relationships between two methods are only valid for the soils and region where the relationship was developed and should not be extrapolated to other regions, even with similar soils.
A unified equation for the viscosity of pure liquid metals

Abstract The following unified equation has been elaborated in the present paper, to describe the viscosity of all liquid metals as a function of temperature: ηi=A⋅Mi1/2Vi2/3⋅T1/2⋅exp(B⋅Tm,iT) $${\eta _i} = A \cdot {{M_i^{1/2}} \over {V_i^{2/3}}} \cdot {T^{1/2}} \cdot \exp \left( {B \cdot {{{T_{{\rm{m}},i}}} \over T}} \right)$$ with ηi, Mi , Vi, Tm,i being the dynamic viscosity, atomic mass, molar volume and melting point of the given metal i, and T is temperature. The above equation was tested on 101 measured points of 15 selected liquid metals, and the average values of the generally valid parameters were found as: A = (1.80 ± 0.39) · 10–8 (J/Kmol1/3)1/2, B = 2.34 ± 0.20. Based on these parameters, the temperature dependence of viscosity was estimated for 32 liquid metals. The above equation was derived by (i) combining Andrade’s equation with the activation energy concept, and (ii) by combining Andrade’s equation with the free volume concept. It is shown, that the activation energy and the free volume concepts have identical roots and lead to identical results. The above equation is shown to be valid for liquid semi-metals (Si, Ge, Sb, Bi), if their actual melting points are replaced by their corrected melting points, corresponding to (unstable) metallic solid crystals. The ratio of viscosity to surface tension of pure liquid metals is discussed, as well.
A Thermodynamic Approach for Modeling Partitioning of Semivolatile Organic Compounds on Atmospheric Particulate Matter: Humidity Effects

Humidity effects on the gas/particle partitioning of the different types of semivolatile organic compounds (SOCs) in the organic layer of wood soot, diesel soot, and secondary aerosols were studied in outdoor environmental chambers. Experimental partitioning coefficients, Kp, of different SOCs were measured using outdoor Teflon film chambers and compared to theoretical Kp values calculated with the aid of activity coefficients and vapor pressures. A thermodynamic model based on group contribution methods was used to estimate SOC activity coefficients in the liquid organic layer of different atmospheric particles. The equilibrated water content in the organic phase of chemi cally different particles was estimated from the activity coefficient of water in the particle's organic liquid and the ambient relative humidity (RH). It was found that predicted SOC activity coefficients (i ) for diesel soot particles were not a strong function of RH. There was, however, a dramatic change in i on wood soot particles f.
Effect of Water Soluble Polymers on Dissolution Enhancement of Ibuprofen Solid Dispersion Prepared by Fusion Method

The purpose of this study was to prepare and characterize solid dispersions of the NSAID Ibuprofen with PEG 6000, Poloxomer 188 and Poloxomer 407 with the intention of improving its dissolution properties. The solid dispersions were prepared by the fusion method. Evaluation of the properties of the dispersions was performed using dissolution studies. The results obtained showed that the rate of dissolution of Ibuprofen was considerably improved when formulated in solid dispersions with PEG 6000 and poloxomer 188. Solid dispersions with poloxomer 407 showed drug retarding capability which may trigger more research in the intension of exploiting this feature to prepare sustained release dosage form. Key words: Ibuprofen; polyethylene glycol; poloxomer; solid dispersion; fusion method; dissolution DOI: 10.3329/sjps.v3i1. 6801 S. J. Pharm. Sci. 3(1): 63-67
Advanced guidance and navigation of small UAVs under GPS-denied environment with experimental validations

OF THE DISSERTATION Advanced Guidance and Navigation of Small UAVs under GPS-denied Environment with Experimental Validations by Liyang Wang Dissertation Director: Xiaoli Bai Small vertical take-off and landing (VTOL) Unmanned Aerial Vehicles (UAVs) are playing more and more important role in recent years for a wide range of applications including wireless communication, topographic mapping, disaster relief, and military action. The size of the UAVs becomes smaller to enable challenging applications such as indoor exploration. With the reduced size of the structure, battery, and on-board sensors, the payload is constrained. As a result, the quality of the on-board sensors and the on-board computation ability of small UAVs are limited. Under these conditions, to complete complicated tasks, research on small VTOL UAVs are required in many aspects. This thesis mainly focuses on four aspects: 1) Object recognition and tracking for vessel deck landings; 2) Simultaneous localization and mapping (SLAM); 3) Wind disturbance estimation; and 4) UAV platform design. Autonomous landing of a quadrotor UAV on a vessel deck is challenging due to the special sea environment. In this thesis, an on-board monocular vision-based solution that provides a quadrotor with the capability to autonomously track and land on a vessel deck platform with simulated high sea state conditions is presented. The whole landing process includes two stages: approaching from a long range and landing after hovering above the landing platform. Only on-board sensors are used in both stages, without external information input. This thesis use Parrot AR.Drone as the experimental quadrotor platform, and a self-designed vessel deck
AUTHENTICATION OF FUEL SPILL STANDARDS USING GAS CHROMATOGRAPHY/PATTERN RECOGNITION TECHNIQUES

Gas chromatography and pattern recognition techniques have been used to develop a potential method to authenticate fuel spill identification standards. The test data consisted of 65 gas chromatograms of JP-4, Jet-A, JP-7, JPTS, JP-5, AVGAS, and Diesel fuels, which were obtained from Mukilteo and Wright Patterson Energy Management Laboratories. A genetic algorithm (GA) was used to identify features in the gas chromatograms of neat jet fuels characteristic of fuel type. Authentication of the fuel recognition standards was achieved by projecting each standard onto a principal component map developed from 64 neat jet fuel samples and the 14 chromatographic peaks selected by the GA. The proposed method has been validated using nine fuel recognition standards purchased from an unnamed commercial supplier.
Foam-derived multiferroic BiFeO3 nanoparticles and integration into transparent polymer nanocomposites

Transparent BiFeO3/PMMA (PMMA = poly(methyl methacrylate)) nanocomposites with a thickness up to 40 µm are obtained via solution film casting of BiFeO3 nanoparticle dispersions. The multiferroic BiFeO3 nanoparticles are obtained in a space confined crystallisation process in a porous carbon matrix and subsequent removal of the matrix. The average crystallite size ranges from 46 nm to 106 nm for materials synthesised at 803 K and 903 K respectively, but, at higher temperature, significant amounts of side products are detected by means of X-ray powder diffraction. The nanoparticles are multiferroic with a magnetic coercivity of 1.88 A m−1 at 400 K and a polarisation of up to 1.04 µC/cm2 at 65 kV/cm (298 K). Surface functionalisation using oleic acid allows the integration into PMMA films with a high transmittance.
Spontaneous formation of hierarchical proton‐conductive structures in sulfonated poly(p‐phenylene terephthalamide) copolymer films

Two partially sulfonated copolymers of poly(p-phenylene terephthalamide) were studied; the sulfonated diamine to nonsulfonated diamine ratios were x = 1 and x = 2. Polymer solutions in water demonstrated lyotropic liquid-crystalline behavior, with the critical concentration for nematic phase formation being around 0.7 wt %. Films of these copolymers could be considered for fuel-cell applications. The in-plane proton conductivities were of the order of 10−3 to 10−2 S cm−1 between 20 and 90 °C. Increasing the sulfonation level resulted in a more conductive material. Spontaneous alignment of the polymer occurred during film formation, as revealed by X-ray diffraction. Scattering along the polymer backbone was observed perpendicular to the film, implying that the polymer chains were homeotropically aligned with respect to the film. The average degree of alignment was determined to be 0.66 and 0.77 for x = 1 and x = 2, respectively. Evidence of secondary layering within the plane of the film was seen in SEM images. These layers could provide a pathway for proton conduction to occur within the plane of the film. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 666–676, 2007