Miracle-dz/UniFAR-FTUs huggingface dataset:
Percolation transition of hydration water in biosystems

Hydration water at the surface of a biomolecule may exist as an ensemble of small clusters or as a hydrogen-bonded spanning network, which homogeneously envelopes the biomolecule. The formation of this spanning water network occurs via an intrinsically rounded quasi-two-dimensional percolation transition. We propose methods to study the percolation transition of hydration water at the surface of a finite object, including the surface of a biomolecule. Application of the developed methods to the various model biosystems demonstrates the percolation transition of hydration water when the hydration level, temperature or pressure is varied. We show that the percolation transition of hydration water is closely related to the conformational transitions of hydrated biomolecules and to the qualitative changes of their dynamics. The nature of this coupling may be clarified by the analysis of the various physical properties when crossing the percolation threshold.
Method for the determination of K shell fluorescence yields

A simple method is proposed for determining the K shell fluorescence yield, ω K , using an NaI(Tl) detector coupled to an active filter amplifier and a 1K multi-channel analyser. By placing the target and the source right on the face of the detector, that is, by forming a 2π geometrical configuration, the intensities are measured by employing weak radioactive sources of strengths of the order of 10 4 Bq. The target criterion is suggested following Bambynek et al.'s prescription for optimization of target thickness. The ω K values were determined using several trials for each target to demonstrate the reliability and reproducibility of the method. The ω K values were obtained for lead, tantalum and gold elemental targets, and also for lead compounds and for some rare earth compounds. These values were compared with the recent standard fitted values of Hubbell et al. and were found to be in close agreement. The method is discussed in detail.
Chemical Potential Perturbation: A Method to Predict Chemical Potential Using Molecular Simulations

Chemical Potential Perturbation: A Method to Predict Chemical Potential Using Molecular Simulations Stan G. Moore Department of Chemical Engineering, BYU Doctor of Philosophy A new method, called chemical potential perturbation (CPP), has been developed to predict the chemical potential as a function of composition in molecular simulations. The CPP method applies a spatially varying external potential to the simulation, causing the composition to depend upon position in the simulation cell. Following equilibration, the homogeneous chemical potential as a function of composition can be determined relative to some reference state after correcting for the effects of the inhomogeneity of the system. The CPP method allows one to predict chemical potential for a wide range of composition points using a single simulation and works for dense fluids where other prediction methods become inefficient. For pure-component systems, three different methods of approximating the inhomogeneous correction are compared. The first method uses the van der Waals density gradient theory, the second method uses the local pressure tensor, and the third method uses the TriezenbergZwanzig definition of surface tension. If desired, the binodal and spinodal densities of a two-phase fluid region can also be predicted by the new method. The CPP method is tested for pure-component systems using a Lennard-Jones (LJ) fluid at supercritical and subcritical conditions. The CPP method is also compared to Widom’s method. In particular, the new method works well for dense fluids where Widom’s method starts to fail. The CPP method is also extended to an Ewald lattice sum treatment of intermolecular potentials. When computing the inhomogeneous correction term, one can use the IrvingKirkwood (IK) or Harasima (H) contours of distributing the pressure. We show that the chemical potential can be approximated with the CPP method using either contour, though with the lattice sum method the H contour has much greater computational efficiency. Results are shown for the LJ fluid and extended simple point-charge (SPC/E) water. We also show preliminary results for solid systems and for a new LJ lattice sum method, which is more efficient than a full lattice sum when the average density varies only in one direction. The CPP method is also extended to activity coefficient prediction of multi-component fluids. For multi-component systems, a separate external potential is applied to each species, and constant normal component pressure is maintained by adjusting the external field of one of the species. Preliminary results are presented for five different binary LJ mixtures. Results from the CPP method show the correct trend but some CPP results show a systematic bias, and we discuss a few possible ways to improve the method.
Electric double layer interaction of ionizable surfaces: Charge regulation for arbitrary potentials

Electrostatic interactions between charged surfaces across an electrolyte solution are commonly described by boundary conditions of constant charge or constant surface potential. These two extremes are in general not appropriate for an equilibrium description of materials with ionizable surface groups, but do provide an upper and lower bound for the interaction energy. We propose a quantitative criterion which permits to evaluate the degree of charge regulation for surfaces with arbitrary electrostatic potential, as considered in the Poisson–Boltzmann theory. Our approach represents a generalization of the linearized regulation model proposed earlier for the framework of Debye–Huckel theory only. Like in the case of low surface potentials, the regulation behavior is generally determined by the competition between the capacities of the diffuse and the compact part of the electric double layer. Our results suggest a new way of using the limiting conditions of constant charge and constant potential to approx.
Precise Synthesis of Dendrimer-Like Star-Branched Polystyrenes and Block Copolymers Composed of Polystyrene and Poly(methyl methacrylate) Segments by an Iterative Methodology Using Living Anionic Polymerization

A series of well-defined dendrimer-like star-branched polys t yrenes (PS)s has been synthesized by developing a new iterative methodology based on "arm-first" divergent approach. In the methodology, the following three reaction steps are needed for the entire iterative synthetic sequence: (1) a linking reaction of α-3-(tert-butyldimethylsilyloxy)propyl- (TBDMSOP-) functionalized polystyryllithium end-capped with 1,1-diphenylethylene with either a core compound with four benzyl bromide (BnBr) functions or chain-end—BnBr—functionalized PS, (2) a transformation reaction of the terminal TBDMSOP group into 3-bromopropyl group, and (3) an introduction reaction of two BnBr functions via the 3-bromopropyl group. The synthetic sequence has been repeated five times to successfully synthesize dendrimer-like star-branched (PS)s up to the fifth-generation (5G). The final 5G polymer was 1.88 x 10 6 in M w value (M w /M n =1.05) consisting of 124 PS branch segments. By using α-functionalized living PMMA with two 3-tert-butyldimethylsilyloxymethylphenyl groups convertible to BnBr functions in the iterative process of the new methodology, two kinds of the 3G dendrimer-like star-branched block copolymers composed of PS, PMMA, PS and PMMA, PS, PMMA introduced at the lG, 2G, and 3G generations, respectively, have also been successfully synthesized. The resulting polymers all herein synthesized were observed to have precisely controlled molecular weights and compositions and narrow molecular weight distributions (M w /M n ≤1.05). Their expected and well-defined structures and low degrees of homogeneity were guaranteed by agreement of both observed and calculated molecular weights of the final polymers obtained at all generation stages.
Evaluation of the potential for co-gasification of black liquor and biofuel by-products : An experimental study of mixing and char reactivity

The increased use of fossil fuels during the last centuries has caused elevated levels of carbon dioxide in the atmosphere. There is significant evidence that this is the cause of global warming. To mitigate the global warming, measures has to be taken to use renewable fuels and make processes more efficient.Catalytic gasification and downstream upgrading of synthesis gas is a promising technology for biofuel production, where previous research in black liquor gasification is currently expanding into a wider fuel feedstock.This work focuses on co-gasification of black liquor and by-products from other biofuel production technologies. The interesting by-products were crude glycerol from biodiesel production and spruce fermentation residue from ethanol production. The main goals were to study if the fuels can mix homogeneously and study the char reactivity. CO2 char gasification for mixtures of black liquor and glycerol or fermentation residue respectively was studied using thermogravimetric analysis (TGA) for four temperatures between 750°C and 900°C.The results show that glycerol can be mixed in all proportions with black liquor and indicate that the char reactivity is unchanged. The sustained char reactivity for blends is attributed to the volatility of glycerol. The fermentation residue does not produce a homogeneous mixture with black liquor and the char is less reactive.More studies should be performed to further elucidate the validity of the results.
Semiconducting properties of Tm doped Yb-ZnO films by spray pyrolysis

In this work, we have investigated the structural, optical and electrical properties of rare earth co-doped zinc oxide thin films prepared by spray pyrolysis technique. X-ray diffraction has shown that the films are polycrystalline and textured with the c -axis of the wurtzite structure along the growth direction. Scanning electronic microscopy and transmission electronic microscopy were used to study the films composition and morphology. Photoluminescence measurements showed that all the films have a strong emission band at around 380 nm. Layers with electrical resistivity values as low as 5.7 × 10 −2 Ω cm were obtained.
Physico-Chemistry of Planetary Atmospheric Entry Plasmas

This contribution deals with the description of the physico-chemistry in the reactive flow produced near the surface of a body entering a planetary atmosphere in hypersonic regime. A shock layer is formed in which a boundary layer is developed where energy is released to the body surface. N2 is chosen as a test-case of Earth atmospheric reentry to illustrate the main characteristics of the flow. The vibrational and electronic specific Collisional-Radiative model CoRaM-N2 is described and implemented in a one-dimensional Euler flow solver. The well-known FIRE II flight experiment conditions are used to illustrate the behaviour of the different ground and excited states of atomic and molecular species. The results show that the three successive phases occur: vibrational excitation, dissociation and ionisation. Radiation plays a minor role. According to the upstream thermodynamic conditions, the boundary layer edge can be in local thermodynamic equilibrium or not. The different strategies using thermal protection systems are discussed to reduce the damaging of the entering body.
Measurement of gas temperature and OH density in the afterglow of pulsed positive corona discharge

The gas temperature and OH density in the afterglow of pulsed positive corona discharge are measured using the laser-induced predissociation fluorescence (LIPF) of OH radicals. Discharge occurs in a 13 mm point-to-plane gap in an atmospheric-pressure H2O(2.8%)/O2(2.0%)/N2 mixture. The temperature measurement shows that (i) the temperature increases after discharge and (ii) the temperature near the anode tip (within 1 mm from the anode tip) is much higher than that of the rest of the discharge volume. Near the anode tip, the temperature increases from 500 K (t = 0 µs) to 1100 K (t = 20 µs), where t is the postdischarge time, while it increases from 400 K (t = 0 µs) to 700 K (t = 100 µs) in the rest of the discharge volume away from the anode tip. This temperature difference between the two volumes (near and far from the anode tip) causes a difference in the decay rate of OH density: OH density near the anode tip decays approximately 10 times slower than that far from the tip. The spatial distribution of OH density shows good agreement with that of the secondary streamer luminous intensity. This shows that OH radicals are mainly produced in the secondary streamer, not in the primary one.
A Comparison of Alternative Approaches to Free Energy Calculations

Critical comparisons of a pair of alternate approaches to free energy calculations are performed. The «single topology» method incorporated in widely-used programs such as AMBER is compared to the «dual topology» approach used by widely-used programs such as CHARMM. For each topological approach, both free energy perturbation (FEP), and thermodynamic integration (TI) methods are characterized. All calculations are performed for the «zero sum» model system of «ethane-to-ethane» in water. The symmetry of the'change in this system allows one to unambiguously evaluate the approach to convergence for a series of simulations
Composition of Chemical and Antioxidant Properties of Pomegranate Juices from Eight

Pomegranate (Punica granatum L.) is an important Iranian-native fruit, which many cultivars are cultivated. The objective of this work was to analyze and compare the chemical composition and antioxidant activity of eight pomegranate cultivars. This study showed that there were significant differences (p < 0.05) among the cultivars in all measured parameters. Total soluble solids content varied from 11.67 to 15.07 (°Brix), pH values from 3.16 to 3.99 and titrable acidity concentration from 0.33 to 2.44 (g/100 g). The level of ascorbic acid was observed in pomegranate cultivars between 9.91 (‘Malas Save’) and 18.42 (‘Malas Yazdi’) (mg/100 g). The highest and lowest level of total anthocyanins was recorded in ‘Malas Yazdi’ and ‘Dom Ambaroti’ (30.11and 5.72 mg/100 g), respectively. The values of total phenolics varied from 295.79 (‘Shirin Pust Ghermez’) to 916.03 (‘Malas Yazdi’) (mg gallic acid /100 g). Antioxidant activity of pomegranate cultivars was found between 18.41 (‘Shirin Pust Ghermez’) and 48.85% (‘Malas Yazdi’). There was a strong
High‐quality nonpolar m ‐plane GaN substrates grown by HVPE

Relatively large size (about 10 mm × 10 mm) m ‐plane GaN substrates are grown by hydride vapor phase epitaxy (HVPE). The high crystalline quality of the substrates was observed by X‐ray diffraction analysis. Typical full widths at half maximum values of X‐ray rocking curves measured for the (10$ \bar 1 $0) and (10$ \bar 1 $2) reflections were 25–35 arcsec and 30–40 arcsec, respectively. The defect density distribution was analyzed from the [10$ \bar 1 $0] direction by the cathodeluminescence method. The dark spot density decreased in the growth direction and could be as low as 2.5 × 105 cm–2. No stacking faults could be seen. The surface roughness after the lapping, polishing and cleaning was measured by atomic force microscopy and the RMS roughness was 0.072 nm. All of the phonon modes that the selection rules allow have been observed in polarized Raman measurements. High‐quality large‐size m ‐plane GaN substrates will enable the realization of commercial production of nonpolar devices. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Origins of ion energy distribution function (IEDF) in high power impulse magnetron sputtering (HIPIMS) plasma discharge

The ion energy distribution function (IEDF) in high power impulse magnetron sputtering (HIPIMS) discharges was studied by plasma sampling energy-resolved mass spectroscopy. HIPIMS of chromium (Cr), titanium (Ti) and carbon (C) targets in argon (Ar) atmosphere was analysed. Singly and doubly charged ions of both the target and the gas were detected. Time-averaged IEDFs were measured for all detected ions at the substrate position at a distance of 150 mm from the target. The effects of target current and discharge pressure on the IEDF were investigated. Measurements were done at two pressures and for three peak discharge currents. The IEDF of both the target and the gas ions was found to comprise two Maxwellian distributions. Quantitative analysis of target IEDFs at a low pressure showed that the main peak had a lower average energy with an approximate value of EAV = 1 eV which is attributed to collisions with thermalized gas atoms and ions. The higher energy distribution has a tail extending up to 70 eV, which is assumed to originate from a Thompson distribution of sputtered metal atoms which, due to collisions, are thermalized and appear as a Maxwell distribution. The proportion of high energy IEDFs for metal ions increases monotonically as a function of Id. The effective ion temperature kBT, extracted from the main low energy peak, showed a weak dependence on peak current. The effective ion temperature extracted from the high energy tail showed a strong correlation with the change in Id. The IEDF at high pressure shows that a proportion of high energy IEDFs was very low and dominated by a low energy main peak. The gas IEDF at high pressure was completely thermalized. The metal-ion-to-gas-ion ratio was found to increase with Id and with the sputtering yield of the target material.
Distribution and correlation of psychiatric symptoms in early stages of parkinson’s disease

The premotor phase of Parkinson Disease (PD) precedes the classical motor phase and the clinical picture is dominated by nonmotor symptoms. The psychiatric symptoms, an important category of nonmotors symptoms, need to be evaluated and treated. The study objective was to assess the frequency of nonmotor symptoms in patients with PD in early stages of the disease and to establish correlations between these symptoms and the features of disease or clinical characteristics of patients. The group of patients enrolled in the study included a number of 43 patients with early PD, enrolled during a period of one year in Neurology Clinic I, from Cluj-Napoca, Romania. For all patients enrolled in the study, the questionnaire NMS-PD QUEST was applied. Psychiatric complaints play an important role as there were no patients who did not present at least one psychiatric symptom and in most cases patients have described a complex of associated symptoms: roughly one third of the patients of both genders complain about 5 symptoms of each of this type, simultaneneously. Within the psychiatric fi eld, the most prevalent symptoms belonged to affective disordersdepression-81,39%, followed by disorders of attention and concentration-79, 06%. Regarding the correlations monitored in the study, the analysis of parameters show that the only statistically signifi cant correlation was with family history of PD. The fi eld of sleep disorders was well represented by insomnia, present in 69.76% of cases, which was followed by excessive daytime sleepiness and sleep with nightmares in equal percentages of 46.51%. The most common psychiatric symptoms reported by the questionnaire even from the early stages were depression, attention and memory problems and those related to impaired sleep. The results presented highlights the importance of questioning the patients about nonmotor complaints from the very beginning of the diagnostic process.
The effectiveness of the nitrification inhibitor dicyandiamide (DCD) for mitigating nitrogen leaching losses from a winter grazed forage crop on a free draining soil in northern Southland.

Evidence suggests that the wintering of stock on forage crops is a significant contributor to N losses from livestock farming. Losses are likely to be exacerbated if crops are grown on shallow free-draining soils types and grazed by dairy cattle. A three-year trial (December 2008 – November 2011) was conducted in northern Southland on a soil classified as having severe vulnerability for nutrient leaching to groundwater. Porous ceramic cups were installed under a brassica crop which was grazed by dairy cows in June each year and the leachate collected regularly for N analysis. The treatments evaluated were with and without a single application of DCD applied at the time of crop grazing. Concentrations of nitrate-N in drainage water ranged from <1 mg/L initially to a peak of >40 mg/L in May 2011. Concentrations of dissolved organic N (DON) also increased from a low initial value (<4 mg/L) to peak at 48 mg/L in May 2011. Estimates of mean annual losses of total nitrogen (TN) in drainage to groundwater averaged 81 kg N/ha/yr and ranged from 8.5 kg N/ha in 2009 to 125 kg N/ha in 2011. The single post-grazing application of DCD did not significantly reduce nitrate leaching losses.
COMPETITIVE DYNAMICS AND CORPORATE PROFITABILITY: AN EMPIRICAL ANALYSIS OF ALUMINUM MANUFACTURING FIRMS IN DELTA STATE, NIGERIA

The paper examined the relationship between competitive dynamics and corporate profitability in aluminum manufacturing firms in Delta State, Nigeria. The study analyzed data collected from one hundred and ninety-eight (198) senior management staff and managers drawn from six (6) major aluminum and steel manufacturing firms. The study adopts a cross-sectional survey research design. A structured self-made research questionnaire was used to collect data for the study while the multiple regression statistics techniques was used to analyze the study hypotheses at a 95% confidence interval and 0.05% level of significance with the aid of Statistical Package for Social Science (SPSS) version 25.0. The reliability of research instrument was obtained through the Crombach’s Alpha Coefficients with all the items above 0.70 which was established by Nunnally (1970). The empirical results of the study found a statistically positive and significant relationship between competitive dynamics such as: competitive pricing, new product launch actions and corporate profitability in the aluminum manufacturing firms in Delta State, Nigeria. From the empirical findings, the study concluded that there is a significant relationship between competitive and corporate profitability through competitive pricing and new product launch actions in the industry. Thus, the study recommend that aluminum and steel manufacturing firms should make it a matter of priority to consider competitive pricing moves and new product launch actions to build on their unique competitive advantage so as to increase their level of corporate profitability in the industry.
Influence of network topology on mechanical properties of network polymers

We studied theoretically how the network topology influences the mechanical properties of polymers. We used conclusions of thermofluctuation theory of fracture and graph theory. The long-term strengths of monofunctional and polyfunctional networks were compared. The cross-link functionality distribution of the polyfunctional networks is a power function. All other conditions being equal, the long-term strengths of the polyfunctional polymer networks are some three to four times the long-term strengths of the monofunctional networks.
Phenanthrolinchinone und Diazafluorene

Es wird die Darstellung der 5,6-Chinone der drei isomeren Phenanthrolinen beschrieben. Aus den Chinonen werden durch Ringverengung uber die Diazafluorenone die entsprechenden neuen Grundkorper, das 1,5-, 1,8- und das 4,5-Diazafluoren gewonnen.