Miracle-dz/UniFAR-FTUs huggingface dataset:
Comparison of surface interactions for NH and NH2 on polymer and metal substrates during NH3 plasma processing

How different plasma species influence the reactions and reactivity of each other during plasma processing is not fully understood, especially with respect to surface interactions. The goal of this study is to provide insight into the relationships between gas-phase NHx species in NH3 plasmas. Specifically, formation of NHx, their relationship with the surface during plasma processing, and the effects of charged species on these interactions are discussed. The surface reactivities of NH and NH2 radicals with different substrate materials during NH3 plasma processing were investigated using the imaging of radicals interacting with surfaces technique. Scatter coefficients, S, for NHx species were obtained as a function of applied rf power for polyimide, polytetrafluoroethylene, and platinum substrates. To investigate the role of ions on the formation of NHx radicals in the gas phase and at the surface, ions were removed (>98%) from the plasma molecular beam. Results from the “ion-free” conditions suggest th.
Temperature dependence of the dynamics of optical spin injection in self-assembled InGaAs quantum dots

We report the temperature dependence of the dynamics of optical spin injection from GaAs barriers into self-assembled quantum dots (QDs) of In0.5Ga0. 5As. Transient circular-polarization properties of photoluminescence (PL) from excited states in QDs depend strongly on the temperature (T) and rate-equation analysis shows the T-dependent dynamics of spin injection. The filling for the majority spin states is strongly suppressed as T increases above 100 K, enhancing the circular polarization degree of PL. This suppression originates from thermal redistribution of electrons from the excited states in the QDs to the barrier. In contrast, spin relaxation during the injection becomes significant at T ≥ 150 K.
Poisonous Effects of Phosalone as an Insecticide on Rumen Degradability of Dry Matter according to in situTechnique

In considering the interaction between microorganisms and insecticides, some certain effects may become significant. These effects involve the potential inhibition or possible germicidal action of insecticides on rumen microbes. Proper functioning of these microorganisms is essential, since they supply approximately 50 to 70% of the energy requirements of ruminants. Any deleterious influence, even of a temporary nature, could have a profound effect on the bacterial activity and subsequently upon the host animal. So a study to investigate the effects of different levels (0, 0.7, 2.8 and 5.6 mg) of phosalone as an insecticide with different levels of calcium bentonite (0 and 100 mg) on in vitro dry matter disappearance was carried out in the farm of animal science in Ferdowsi University of Mashhad, Iran in 2012. The study indicated that all the levels of phosalone had not any significant effect on in situ dry matter disappearance (ISDMD),only the effect of phosalone was significant after 24h incubation (p<0.05). There was a significant effect (P<0.01) for calcium bentonite for effective dry matter digestibility (EDMD), the rapidly soluble fraction (a) and the potentially degradable fraction (b). In this experiment calcium bentonite is tested as toxin binder for decreasing the probably deleterious effects of phosalone on rumen degradability of dry matter.
Structural Features of 2′,3′-Dideoxy-2′,3′-Didehydrocytidine, A Potent Inhibitor of the HIV (AIDS) Virus

Abstract The structure and conformation of 2′,3′-dideoxy-2′,3′-didehydrocytidine (2′,3′-dideoxycytidin-2′-ene, d4C), a potent inhibitor of the human immunodeficiency virus, was determined by X-ray crystallography. The nucleoside crystallizes in the orthorhombic space group P212121 with cell dimensions a = 8.603(1), b = 9.038(1), c = 25.831(2) A and with two independent molecules in the asymmetric unit (Z = 8). Atomic parameters were refined by full-matrix least squares to a final value of R = 0.033 for 2258 observed reflections. The molecules are quite flexible: in molecule A the glycosyl torsion angle (XCN) is 61.3° and the -CH2OH side chain is in the gauche + orientation while in molecule B XCN = 19.8° and the side chain is trans. The five-membered rings are slightly puckered (∼0.1 A), 04′ being endo in molecule A and exo in molecule B. A mechanism is proposed for the known instability of 2′,3′-unsaturated nucleosides.
Ambulatory assessment of human body kinematics and kinetics

Traditional human movement analysis systems consist of an optical position measurement system with one or more 6D force plates mounted in a laboratory. Although clinically accepted as `the golden standard' for the assessment of human movement, the restriction to a laboratory environment with its limited measurement volume prevents these systems to be used in an ambulatory environment. To overcome this limitation, this thesis proposes two measurement systems. First, an instrumented shoe is proposed that is used to assess the 3D ground reaction force, the center of pressure trajectory, the center of mass trajectory, and the movement of the foot. The instrumented shoe consists of an orthopedic sandal with two 6D force/moment sensors beneath the heel and the forefoot, and two inertial sensors rigidly attached to the force/moment sensors. Second, a measurement system is proposed which fuses inertial and magnetic sensing to estimate relative positions and orientations on the human body. Fusion is achieved using a realtime Extended Kalman Filter (EKF) with a tightly coupled structure. Change of position and orientation is predicted by integration of acceleration and angular velocity measured by an inertial sensor. Magnetic updates are used to reduce the inherent integration drift due to noise and a fluctuating offset. To minimize energy consumption, the magnetic system only actuates if the uncertainty associated with the position and orientation exceeds a predefined threshold. Moreover, only the coil delivering most information for the reduction of the uncertainty is actuated.
Characterization of a Linear Melamine Formaldehyde Resin

Abstract A novel linear melamine formaldehyde resin on the basis of the bifunctional tetramethylmelamine was created. It was found to posses several promising properties for industrial applications. Structural characterization of the material at its various production states was achieved with different mass spectrometric techniques. Liquid chromatography-ion trap mass spectrometry was used to completely separate the resins and identify the individual components. Detection with a diode array detector indicated a change of spectroscopic properties with the degree of polymerization. The material was also analyzed with analytical pyrolysis and a gel permeation chromatography system hyphenated to a mass spectrometer in order to unambiguously determine the molar masses.
Microfluidic Chromatography for Early Stage Evaluation of Biopharmaceutical Binding and Separation Conditions

Optimization of separation conditions for biopharmaceuticals requires evaluation of a large number of process variables. To miniaturize this evaluation a microfluidic column (1.5 µL volume and 1 cm height) was fabricated and packed with a typical process scale resin. The device was assessed by comparison to a protein separation at conventional laboratory scale. This was based upon measurement of the quality of packing and generation of breakthrough and elution curves. Dynamic binding capacities from the microfluidic column compared well with the laboratory scale. Microfluidic scale gradient elution separations also equated to the laboratory column three orders of magnitude larger in scale.
Infrared spectroscopy of strained BaTiO3/SrTiO3 superlattices on scandate substrates

Polarized infrared reflectance of ferroelectric [(BaTiO)/(SrTiO)] superlattices grown on DyScO, TbScO, EuScO and SmScOsubstrates by reactive molecular beam epitaxy was measured. Infrared spectra (30–3000 cm) were taken independently from the (110) cut of bare substrate and the substrate covered with superlattice in two polarizations: along the -axis and perpendicular to it. The phonon parameters and dielectric function of the superlattice were extracted using a fitting procedure to study the influence of the strain induced by different substrates. The phonon frequency dependence on the substrate-induced strain was varying from 75 to 95 cm. The superlattice static permittivity was estimated from that data, which varies from 150 to 270 depending on substrate and polarization. The highest permittivity was obtained for the EuScO substrate.
Development of models and methods to simulate peptide-assisted nucleation and growth of calcium-minerals

In the past years, several so far unknown phenomena such as the existence of different pre-nucleation structures have been observed experimentally, and have generated a new understanding of the processes that occur at the molecular scale during nucleation and growth of crystals. The implications that pre-nucleation structures might have in the process of biomineralisation are not yet well-understood. The mechanisms, by which biomolecular modifiers such as peptides might interact with pre-nucleation structures and thus influence the nucleation process of minerals, are numerous. Molecular simulations are well suited for the analysis of the formation of pre-nucleation structures in the presence of modifiers. This thesis presents an approach to study the interactions of peptides with the solvated constituents of the forming crystals by means of Molecular Dynamics simulations. As a first step towards informative simulations, the quality of existing forcefields with respect to the description of oligoglutamates interacting with calcium ions in aqueous solution was tested. It was found that large discrepancies between well-established forcefields exist, and that non of the tested forcefields gave a realistic description of the ion-pairing of these complex ions. Therefore, a strategy to optimise existing biomolecular forcefields in this respect was developed and it was found that relatively small changes in the parameters of the ion–peptide van-der-Waals interactions were sufficient to obtain a reliable model for the system of interest. The comprehensive sampling of the phase space of the systems is particularly challenging due to the large number of degrees of freedom and the strong interactions between calcium ions and glutamate in solution. The Biasing Potential Replica Exchange Molecular Dynamics method was therefore adapted to the enhanced sampling of oligoglutamates, and peptides of different chain lengths were simulated in the presence of calcium ions. With the help of the sketch-map analysis method numerous stable ion–peptide clusters, which might affect the formation of pre-nucleation structures, were identified from these simulations. Depending on the chain length of the peptide, these clusters exhibit characteristic distances between the calcium ions. These distances resemble some of the distances between calcium ions in those phases of calcium oxalate crystals, which are grown in the presence of oligoglutamates. The analogy of distances between calcium ions in solvated ion–peptide clusters and in calcium oxalate crystals might be interpreted as an indication for the importance of ion–peptide clusters in the nucleation and growth of biominerals and it is a possible explanation for the ability of oligoglutamates to influence the phase of the forming crystals, as it has been observed in experiments.
Structural and optical properties of TiO2 thin films annealed in O2 and N2 gases flow

Titanium dioxide (TiO2) thin films were prepared by ion-assisted electron-beam deposition on glass at room temperature and were annealed by rapid thermal annealing in O2 and N2 gas flow. TiO2 thin films annealed in N2 gas flow are (110) rutile phase and (101) anatase phase, but in O2 gas flow are (110) rutile phase. The optical band gaps of the TiO2 thin films are increased to 3.281 eV with annealing treatment of 300 ~ 500 °C in O2 gas flow and to 3.271 eV in N2 gas flow. However, the band gap begins to decrease to 3.277 eV at the annealing temperature of 600 °C in O2 gas flow and to 3.257 eV in N2 gas flow, respectively.
The Distribution of Metals in Soils and Pore Water at Three U.S. Military Training Facilities

Small arms firing ranges at military training facilities can have enormous heavy metal burdens (percent level) in soils. Currently there are few published works that quantify the metal content of soils and waters at military installations or speculate on the potential for migration of these contaminants into groundwater. This article documents metals in soils and waters at nine small arms training ranges at three military installations in the U.S. Soil samples were collected from the surface and shallow subsurface. The results demonstrated that lead, antimony, copper, and zinc were the principal contaminants of interest and mapping a site's lead and copper surface distributions would adequately define the extent of impacted soil. Lower metal concentrations at three of the ranges reflected previous remediation by means of physical separation and mechanical removal of metallic fragments followed by fixation treatment with MaectiteTM. Except for the treated ranges where mixing had occurred, subsurface soil samples indicated limited vertical migration. Several of the ranges were also monitored for trace element migration in the vadose zone by means of suction-cup lysimeters. This pore-water sampling indicated ceramic suction-cup lysimeters are useful for assessing relative concentrations but require care in evaluation because of potential sorption losses. Monitoring of soil water at ranges should include antimony and zinc; the former because, in contrast to the other metals, it is typically soluble in an anionic form, and the latter because of its greater solubility and mobility.
Elektronenkoinzidenzmessungen an kleinen Molekülen mit hoher Energieauflösung

Subject of this thesis is the performance of energetically highly resolved coincidence experiments on gaseous molecules after their ionization with synchrotron radiation. Fur this purpose a new apparatus has been set up. This apparatus consisted of an energydispersive, hemispherical electron analyzer, which was enhanced with respect to the possibility to measure the time-of-flight of each electron individually. Additionally, for the coincidence measurements, electron time-of-flight spectrometers have been newly built up and an angle resolving ion-mass-spectrometer has been adapted to harmonize with the apparatus. After combining this apparatus with drift-tube type time-offlight spectrometers, pure photo–Auger-electron coincidences were measured on the N2O molecule for the first time. Thus, it became possible, to separate the individual contributions from K-shell ionization of the chemically shifted nitrogen atoms to the Auger spectrum of N2O. In combination with the ion-spectrometer, the resonant Auger decay of the O2 molecule after excitation of the σ∗ resonance could be observed in coincidence with the respective ionic fragment. In this process, molecular dissociation and resonant Auger decay occur on the same time-scale, which results in an angle-dependent Doppler shift of the kinetic electron energies. By coincident measurement of the Auger electron and the positively charged ion-fragment, the understanding of the Doppler-splitting as a result of coremomentum-transfer induced destruction of coherence or localization in the electron wave function could be confirmed. Furthermore, for the first time, the scattering of a photoelectron on the dissociating fragments and a charge transfer between those fragments could be observed.
A modified diffusion‐based methane sensor and its application in freshwater sediment

Methane is the main end product of anaerobic degradation in freshwater sediments. The flux of methane from the sediment into the water column, and possible methane oxidation at the sediment surface, can be estimated on the basis of its distribution in the sediment and the overlying water. Nonetheless, the quantification of methane in sediments at high spatial resolution is difficult, owing to its chemical inertia. In this study, we describe the improvement of a diffusion‐based methane sensor and its application in freshwater sediment cores. The sensor consists of a steel cannula with small openings, which are covered by thin silicone tubing. Methane diffuses into the cannula and is flushed directly to a flame ionization detector for quantification. With this sensor, methane profiles in freshwater sediment can be measured at high spatial (1.5 mm) and temporal (3 minutes per measurement) resolution. The detection limit was 2 µmol L−1. The relative accuracy of the sensor was ± 15% with a precision of ± 7.5%. Analysis of fine‐scale methane profiles in littoral and profundal sediments of Lake Constance indicate that owing to structural inhomogeneities and temporal changes a high‐resolution analysis is required to allow exact calculations of diffusive fluxes and turnover rates of methane.
Mathematical and Artificial Neural Network Models to Predict the Membrane Fouling Behavior of an Intermittently‐Aerated Membrane Bioreactor Under Sub‐Critical Flux

This study established a mathematical model and an artificial neural network (ANN) model based on the theory of critical flux filtration to predict the membrane module fouling performance of an intermittently aerated membrane bioreactor (IAMBR) while simultaneously conducting a prediction performance evaluation of the two models. The key parameters of the mathematical model, such as constant rate, fouling propensity, and others, were determined by a short-term step-flux experiment and a long-term filtration experiment. The transmembrane pressure jump point (tsus) of the long-term filtration under sub-critical flux was calculated using the key parameters. An ANN model was also established based on the critical flux theory and the initial weights of the network model were optimized using a genetic algorithm, which accelerated the convergence of the model. The evaluation results indicated that the ANN model had a better simulation performance under the intermittently aerated mode, but the mathematical model predicted tsus more steadily. Therefore, a more in-depth investigation is required to obtain an elaborate evaluation of those two models.
Synthesis of nucleoside analogues and peptides for nanoore analysis and controlled bioactivity

This research describes the synthesis of nucleoside analogues and peptides, and their application to nanopore technology and cell biology. Nanopore technology is a technique in which analytes are detected by disturbances in ionic current caused as they traverse a pore, at a fixed applied potential. Here potential applications of the technology are explored. A nanopore-based method to detect enzymatic activity was investigated. The technique involved the detection of peptide fragments proteolytically released from a solid-support. The released fragments gave rise to distinct electrical signals which facilitated their identification and characterisation. The frequency with which they traversed the pore was indicative of enzyme activity. The technique was successfully applied to the detection of the protease enzyme, renin, in the presence of human serum. An approach to count nucleotide repeat sequences, which are the basis of forensic DNA fingerprinting, was also investigated. It was hypothesised that chemically modified copies of the repeat regions could be generated using primer extension and nucleoside analogues. The copying could be performed such that a single analogue was incorporated per repeat. Ensuing nanopore analysis would then give rise to electrical signals in which the analogues could be identified from unique signals. The number of repeat sequences could simply be determined by counting the number of signals. It was envisaged that this could be achieved using adamantane-modified nucleosides. However, these did not give rise to the expected result. Inspired by the adamantane project, analogues of the drug, azacytidine were synthesised. Azacytidine is used to treat cancers that arise due to epigenetic modifications of DNA. It was hypothesised that its side-effects could be mitigated using photocaged-derivatives of the nucleoside, as these would enable greater temporal and spatial control of drug release. Analogues of azacytidine were successfully synthesised and shown to be uncaged back to the parent nucleoside.
A Mesoscopic Model for an Asphaltene and Complex Mixtures of Asphaltenes

A representation for an asphaltene system and asphaltene mixtures is proposed based on experimental data reported by Sócrates et al. These were modeled at the mesoscopic level by applying dissipative particle dynamics (DPD), where DPD beads correspond to the main structure that constitutes the real asphaltene fraction. The experimental solubility parameters were used to obtain the Flory–Huggins parameter, based on which the repulsive parameters aij, were calculated using the methodology developed by Groot and Warren (1997). Finally, the obtained asphaltene model, it presents the evolution of the Interfacial Tension in DPD unit values, according to the solvents used. It also describes how to obtain the asphaltene solubility parameters.
Co‐growsth of Straight and Coiled Carbon Nanofibers by Ethanol Catalytic Combustion Technique

We have successfully fabricated straight carbon nanofibers containing coiled carbon nanofibers by ethanol catalytic combustion technique. In our experiment, copper plate was employed as substrate, transition metal salt solution as catalyst precursor, and ethanol as carbon source. The morphology and microstructure of the obtained carbon nanostructures have been investigated and their growth mechanism has been discussed.
Preparation of Graphene Oxide/Polyaniline Nanocomposite with Assistance of Supercritical Carbon Dioxide for Supercapacitor Electrodes

We report a facile strategy to prepare graphene oxide (GO)/polyaniline (PANI) nanocomposite by in situ polymerization with the assistance of supercritical carbon dioxide (SC CO2). The morphology and chemical structure of the synthesized samples were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), FT-IR, Raman, and UV–vis spectrophotometry. As a result, PANI nanoparticles uniformly cover the GO sheets with the help of SC CO2, and the formation mechanism is suggested. The morphologies of GO/PANI nanocomposites can be controlled through adjusting the concentration of aniline. The GO/PANI nanocomposite exhibits better specific capacitance and cycle stability than pure PANI and GO owing to the synergistic effect of GO and PANI nanoparticles, making it promising application in electrochemical devices.
PERFORMANCE LIMITS OF PULSE TUBE CRYOCOOLERS USING 3HE

The enthalpy, entropy, and exergy flows resulting from the real gas effects of 3He in ideal pulse tube cryocoolers are described. The discussion follows a previous description of the real gas effects of 4He in ideal pulse tube cryocoolers and makes use of a recently developed model of the thermophysical properties of 3He. This model is used to describe how the thermodynamic flows are affected by real gas phenomena of 3He and compares these effects to similar effects for 4He.The analysis was done over the pressure range 0.3–2 MPa and temperatures down to 1 K. At 2 MPa there is almost no difference in the cooling power between 3He and 4He. At lower pressures, using 3He is advantageous. There is a 1–2 K reduction in the 3He cooling power vs. temperature curves compared to those for 4He in the 0.3–1 MPa range.