Miracle-dz/UniFAR-FTUs huggingface dataset:
Influence of CuO Additions and Sintering Temperature on Microwave Dielectric Properties of La(Mg1/2Sn1/2)O3 Ceramics

In this study, the microwave dielectric properties of La(Mg 1/2 Sn 1/2 )O 3 ceramics have been investigated for application in mobile communication. CuO was selected as liquid sintering aids to lower the sintering temperature of La(Mg 1/2 Sn 1/2 )O 3 ceramics. It is found that the X-ray diffraction patterns of the La(Mg 1/2 Sn 1/2 )O 3 ceramics exhibited no phase difference with 0.5 wt% at different sintering temperatures. The maximum value of the dielectric constant and the quality factor Q × f can be obtained with 0.5 wt% CuO additive and sintered at 1550°C for 4 h. The temperature coefficient of resonant frequency τ f is -83 ppm/°C was measured for La(Mg 1/2 Sn 1/2 )O 3 ceramics with 0.5 wt% CuO sintered at 1550°C for 4 h.
Controlled release of aspirin from pH‐sensitive chitosan/poly(vinyl alcohol) hydrogel

The aim of this study was to develop a cheap, pH-sensitive enteric coating of aspirin with biocompatible polymers. A novel approach was used to develop enteric coating from chitosan (CS) and poly(vinyl alcohol) (PVA). Solutions of CS and PVA (5 : 1 mol ratio) were mixed and selectively crosslinked with tetraethoxysilane. IR analysis confirmed the presence of the incorporated components and the existence of siloxane linkages between CS and PVA. The crosslinking percentage and thermal stability increased with increasing amount of crosslinker. The response of the developed coating in different media, such as water, pH (nonbuffer and buffer), and ionic media showed hydrogel properties. All hydrogels showed low swelling in acidic and basic pH media, whereas maximum swelling was exhibited at neutral pH. This pH sensitivity of the hydrogel has been exploited as enteric coating for commercial aspirin tablets. The dissolution test of enteric-coated aspirin tablet in simulated gastric fluid (pH 1.2) showed 7.11% aspirin release over a period of 2 h, whereas a sustained release of remaining aspirin (83.25%) was observed in simulated intestinal fluid (pH 6.8). © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Analysis of the current dependency of the small signal gain spectrum in InAs/InP(100) quantum-dot amplifiers

InAs/InP(100) quantum-dot amplifiers have been fabricated with a 1700nm peak wavelength. The measured small-signal gain spectra have been analyzed with a quantum-dot rate-equation model. The average energies of the ground state EGS=0.716eV and the excited state EES=0.760 transitions have been determined. The origin of the spectral behavior has been analyzed.
Physics of the Switching Kinetics in Resistive Memories

Memristive cells based on different physical effects, that is, phase change, valence change, and electrochemical processes, are discussed with respect to their potential to overcome the voltage–time dilemma that is crucial for an application in storage devices. Strongly non‐linear switching kinetics are required, spanning more than 15 orders of magnitude in time. Temperature‐driven and field‐driven crystallization, threshold switching, ion migration, as well as redox reactions at interfaces are identified as relevant mechanisms. In phase change materials the combination of a reversible threshold switching and extremely large crystal growth velocities at high voltages enables ultra‐fast resistive switching whereas lower voltages will not be sufficient to overcome the energy barrier for crystallization. In electrochemical cells it depends on the voltage regime, which mechanism is the rate‐determining one for switching. While electro‐crystallization dominates at low voltages, electron transfer in the medium voltage range and a mixture of electron transfer and ion migration at high voltages. In valence change materials, ion migration is found to be accelerated by a combined effect of electric field and local temperature increase due to Joule heating. All discussed types of resistive switches can provide sufficient non‐linearity of switching kinetics for overcoming the voltage time dilemma.
Thin Film Structure of Tin(II) Iodide

Thin films of tin(II) iodide were prepared and characterized. The lattice structure of thin films determined by X-ray diffraction is different from that of bulk SnI 2 . This change of lattice is explained by a polymorphous transition of monoclinic α-SnI 2 to hexagonal β-SnI 2 . The unit cell parameters of β-SnI 2 are a = (4.506 ± 0.014) A, c = (6.946 ± 0.011) A. Thin films of β-SnI 2 have predominant [001] orientation.
Role of Aluminosilicate deposits in Lead and Copper Corrosion

Aluminosilicates frequently deposit onto plumbing materials in distribution systems. Such solids were previously believed to provide some degree of corrosion protection to pipes—although at the expense of increased head loss, reduced flow, and consumer complaints related to postprecipitation. However, this work demonstrates that new copper and lead pipe sections did not benefit from the deposition of aluminosilicate solids. In fact, in most situations the presence of solids actually caused the release of more metal to drinking water compared with solutions without solids. Final pH played a key role in determining the extent of copper corrosion, and the aluminum deposits prevented increases in pH during stagnation through a buffering action.
Etude au microscope électronique de plasmas contenant de l’acide désoxyribonucléique

Mit Hilfe einer Os-Fixation unter bestimmten Bedingungen ist es möglich, in den Nukleoiden von 5 verschiedenen Bakterienarten ein feinfädiges Nukleoplasma zu erhalten. Abweichungen von der Standardfixation führen zu den üblichen, mehr oder weniger groben Einschlüssen in einer leeren Kernvakuole. Ein PH von 6, die Anwesenheit von Aminosäuren oder Peptiden während der Osmiumfixation und eine Stabilisierung mit Uranylacetat erwiesen sich als wesentlich, um ein feines Nukleoplasma zu erhalten. Die äußere Form der Kernvakuole ist sehr variabel und für die Teilungsphasen nicht spezifisch. Die biologischen Konsequenzen dieser Beobachtungen werden diskutiert und eine Hypothese betreffend die Mechanismen der Fixation des Nukleoplasmas aufgestellt.
Conformational flexibility of disaccharides investigated by multiple field carbon‐13 nuclear spin relaxation

Multiple‐field carbon‐13 NMR relaxation studies were performed on four disaccharides with different sugar residues, anomeric configurations and substitution positions. Measurements were made in dimethyl sulfoxide at 300 K, leading to conditions outside the extreme narrowing regime. Global correlation times differed between the disaccharides and scaled well with the number of hydroxyl groups of the disaccharides that can hydrogen bond to solvent. The Lipari–Szabo generalized order parameter was similar for the disaccharides with an average of S2 = 0.75 ± 0.03 when a carbon–proton distance of 109.8 pm was used. However, the flexibility at the disaccharide level is expected to be more restricted (higher value of S2) since a longer carbon–proton distance is judged to be more appropriate. Copyright © 1999 John Wiley & Sons, Ltd.
Spectrophotometric characterization of useful dyes in laser photodynamic therapy

This paper present the physico-chemical properties of some synthetic porphyrin dyes obtained at ZECASIN SA. We have measured the absorption, excitation and fluorescence spectra of these dyes in different solvents. From them we have concluded that the most reliable due for our studies concerning the photodynamic therapy with UV lasers is Zn II- tetrakis-sulfonatophenyl porphyrin.
Comparative efficacy study of different serological tests for the diagnosis of brucellosis in bovines

The application of multiple serological assays currently available for the detection of Brucella antibodies in various species of animals indicates that no single test can detect all infected animals and therefore, combination of serological tests should include more sensitive tests designed to reduce the number of false negative reactions which contribute to the persistence of infection as a herd problem. So the presnt study was conducted to evaluate the comparative efficacy of RBPT and STAT to i-ELISA determined with regards to their sensitivity and specificity in the diagnosis of bovine brucellosis for detecting antibodies in cows and buffaloes. In present study seropositivity for Brucella antibodies were detected by i-ELISA, RBPT and STAT in 618 serum samples of cattle and buffaloes, comprising of 296 from cattle and 322 from buffaloes. Of these 12.46%, 20.06% and 35.92% of serum samples were found to be positive by RBPT, STAT and i-ELISA,, respectively showing higher efficacy i-ELISA followed STAT and RBPT.The sensitivity of RBPT and STAT was found to be of 34.68% and 55.86%, respectively, considering i-ELISA as a gold standard test while specificity was found to be of 98.48% and 98.99%, respectively. Thus, STAT was found to be more sensitive and specific than that of RBPT.
On the dual role of the Knudsen layer and unsteady, adiabatic expansion in pulse sputtering phenomena

When a surface is bombarded with pulses as from a laser and the number of monolayers sputtered per pulse is sufficiently small, the emitted particles fly freely from the target surface. For yields comparable to 0.5 monolayer in 10 ns, a limited number of gas‐phase interactions is known to occur, leading to a Knudsen layer. As a result the particles develop moderate forward peaking (∼cos4 θ) and begin to flow (Mach number, M≊1). It is common, however, for yields to exceed 0.5 monolayer in 10 ns. We show that the resulting gas‐phase interactions cause the Knudsen layer to evolve into an unsteady, adiabatic expansion which is formally like a gun which fires a finite charge into an infinite, one‐dimensional barrel. An explicit solution can be obtained which has the form a=f1(x/t) and u=f2(x/t), where a is the speed of sound and u is the flow velocity. The solution is assumed to be valid up to a distance where the gas density ρ falls to the critical value ρc where free flight sets in. The particles are then ch.
Dewaxing Process Control Using Near-Infrared Spectroscopy

Near-infrared (NIR) spectroscopy and multivariate analysis were applied to estimate the oil content in paraffin streams. On the basis of studies of prepared mixtures, the system NIR/PLS (partial least-squares method) has good predictive capability and could be used to develop an integrated process control for base oils and wax production. The accuracy, difference between predicted and measured oil content, was within 0.5% weight equivalent to that specified in the standard test method ASTM D 721.
The soil skeleton, a forgotten pool of carbon and nitrogen in soil

To evaluate the contribution of rock fragments to the soil’s total carbon content, the soil of 26 sites, ranging from the Canadian Arctic to the Jordan desert, was analysed for the content of organic C and total N in both fine earth and skeleton fractions. The soils, uncultivated and cultivated, are derived from 11 parent materials: sandstone, mica‐schist, granite, gneiss, basaltic pyroclastites, trachyte, dolomite, beach deposits, clay schist, marl and serpentinite. For each soil horizon the contents of fine earth and skeleton were determined by volume. Both fractions were analysed for bulk density, total and organic C and total N. Our results indicate that rock fragments contain amounts of C and N that depend on the nature of the parent material and on its resistance to the weathering processes. The C and N of both fine earth and skeleton were used to calculate the contents of these elements for three depths. At each depth, the skeleton contributes C and N to the soil depending on its abundance. We conclude that the contribution of the rock fragments to the soil C and N cannot be predicted from the soil taxa, but can from the parent material. Calculations that exclude C and N of the skeleton could lead to errors in the estimates of these two elements in soils.
Synthese und Chiralität des (-)-Cannabidiols Vorläufige Mitteilung

N, N-Dimethylformamide-dineopentylacetal mediates the direct formation of (-)-cannabidiol from (+)-trans- or (+)-cis-p-menthadiene-(2,8)-ol-(1) and olivetol. This reaction provides a simple synthetic entry into the series of optically active constituents of haschisch and defines at the same time the chirality of these compounds.
Total Synthesis of (±)-Methyl Atis-16-en-19-oate via Homoallyl−Homoallyl Radical Rearrangement

Total synthesis of (±)-methyl atis-16-en-19-oate (5c), a tetracyclic diterpenoid possessing a bicyclo[2.2. 2]octane ring system, was accomplished. Intramolecular Diels−Alder reaction of tetraene 14 was employed in a construction of kaurene skeleton 13. The pivotal step involved a homoallyl−homoallyl radical rearrangement process of (±)-methyl 12-hydroxykaur-16-en-19-oate monothioimidazolide 12, which led to 5c in good yield. Interestingly, treatment of methyl 12-oxo-kaur-16-en-19-oate 30 with hydrazine monohydrate in the presence of KOH in bis(ethylene glycol) at 200 °C resulted in cyclopropanation to furnish, directly, trachyloban-19-oic acid (4b), together with kaur-16-en-19-oic acid (6b).
Quantification of line-edge roughness of photoresists. II. Scaling and fractal analysis and the best roughness descriptors

A search for the best and most complete description of line-edge roughness (LER) is presented. The root mean square (rms) value of the edge (sigma value) does not provide a complete characterization of LER since it cannot give information about its spatial complexity. In order to get this missing information, we analyze the detected line edges as found from scanning electron microscope(SEM)image analysis [see Paper I: G. P. Patsis et al., J. Vac. Sci. Technol. B 21, 1008 (2003)] using scaling and fractal concepts. It is shown that the majority of analyzed experimental edges exhibit a self-affine character and thus the suggested parameters for the description of their roughness should be: (1) the sigma value, (2) the correlation length ξ, and (3) the roughness exponent α. The dependencies of ξ and α on various image recording and analysis parameters (magnification, resolution, threshold value, etc.) are thoroughly examined as well as their implications on the calculation of sigma when it is carried out by averaging over the sigmas of a number of segments of the edge. In particular, ξ is shown to be connected to the minimum segment size for which the average sigma becomes independent of the segment size, whereas α seems to be related to the relative contribution of high frequency fluctuations to LER.
Electronic and Optical Properties of Rare Earth Oxides: Ab Initio Calculation

In this work, we have investigated the electronic and optical properties of the technologically im- portant rare earth oxide compounds—X2O3 (X: Gd, Tb) using the density functional theory within the GGA. The band structure of X2O3 have been calculated along high symmetry directions in the first brillouin zone. The real and imaginary parts of dilectric functions and the other optical res- ponses such as energy-loss function, the effective number of valence electrons and the effective optical dielectric constants of the rare earth sesquioxides (Gd2O3 and Tb2O3) were calculated.
Validation of inhomogeneous Magnetization Transfer (ihMT) as a myelin biomarker

The ihMT (inhomogeneous Magnetization transfer) signal qualitatively demonstrates sensitivity for myelinated structures. However, image intensity and contrast vary with the saturation parameters, further questioning the specificity of ihM for myelin. This study validated ihMT as a myelin biomarker by demonstrating for various ihMT sequences, linear relationships between ihMT signal and intensity of fluorescence microscopy (a quantitative myelin specific histology technique) collected in plp-GFP mouse brain.
Spectrophotometric Methods For The Determination Of Lipoic Acid By Using MBTH And Ferric Chloride

The oxidative coupling of the proposed method is simple, rapid and sensitive with reasonable precision and accuracy. The precision of the method was found by analyzing a set of eight solutions, each containing a final concentration value approximately in the middle of the Beer’s law range. The percent relative standard deviation in this method is presented in table-2. The accuracy of the method was determined by taking different known amounts (with in Beer’s law limits) of the drug and analyzing them by proposed method. The results are given in table – 3. In the determination of Lipoic acid the excipients usually present in formulations (glucose, starch, sodium hexa phosphate and some vitamins) and the other antioxidants and antidiabetics did not interfere.
Exploring lag times in a pair tracing and debugging eye-tracking experiment

This paper investigated the leader/follower patterns that possibly occurred in a remote pair programming eye-tracking experiment. We intended to build the profile of the initiator and the follower and explore the lag times inherent to pairs categorized based on prior knowledge using the diagonal recurrence profile. Findings revealed that in a pair programming setup, the initiator was the low prior knowledge participant. We defined the “initiator” as the one who encountered a problem in the code first and hence initiated the contact to ask for help, and the “follower” was the one who responded to help. The characteristic lag times based on prior knowledge were 2.33 seconds for both high prior knowledge pairs, 1.96 seconds for both low prior knowledge pairs, and 1.51 seconds for mixed prior knowledge pairs.
The Anomeric Equilibrium in d-Xylose: Free Energy and the Role of Solvent Structuring

Standard molecular dynamics (MD) and free energy simulations have been used to analyze the anomeric equilibrium for d-xylose in aqueous solution. This molecule was selected as a simple model for the anomeric effect in sugars since there are no complications arising from the rotameric distribution of a primary alcohol. As in previous studies of glucose, the free energy calculations found a small free energy difference (0.15 kcal/mol favoring the α form) between the anomers; the experimental value is also small (−0.38 kcal/mol) but favors the β form. Thermodynamic integration analysis of the components contributing to this result showed that, as in the case of glucose, the free energy difference results from the balance between an internal term favoring the α anomer and a solvation term favoring the β anomer. The validity of the partitioning is confirmed by direct evaluation of the energy difference and its components from long standard MD simulations of each anomer. Hydrogen bonding analysis of the MD simu.
Monte Carlo calculation of the contribution of backscattered electrons to secondary electron emission from aluminium

A Monte Carlo model for the simulation of electron penetration into aluminium and for the generation and emission of secondary electrons is presented. Monte Carlo calculations for the penetration and backscattering of primary electrons show good agreement with experiment, while the dependence of the secondary electron yield on the primary electron energy show qualitative agreement with experimental measurements. beta , which is defined as the relative efficiency of backscattered electrons for producing secondary electrons which escape the surface over that of the primary electrons on their inward path, is found to be approximately 6-7 for primary electrons in the energy range 3-25 keV.
Improved thermosets obtained from diglycidyl ether of bisphenol A/4,4′-diaminodiphenylsulfone based on a new epoxy-terminated hyperbranched polymer

A new hyperbranched polymer (HBP) with a flexible aromatic skeleton and terminal epoxy groups was synthesized to improve the toughness of diglycidyl ether of bisphenol A. The HBP was characterized using nuclear magnetic resonance, Fourier transfer infrared spectroscopy and gel permeation chromatography. The effect of HBP on the thermomechanical and mechanical properties of modified epoxy systems was studied. For evaluating the efficiency of the modified epoxy systems, composite samples using glass fiber cloth were molded and tested. Using dynamic mechanical analysis, a slight reduction in glass transition temperature (Tg) with increasing HBP content was observed. Analysis of fracture surfaces revealed a possible effect of HBP as a toughener and showed no phase separation in the modified resin systems. The results showed that the addition of 15 phr HBP maximized the toughness of the modified resin systems with 215 and 40% increases in impact and flexural strengths, respectively. Tg and heat resistance of cured modified resin systems decreased slightly with an increase in HBP content and, at 15 phr HBP, only a 2.6% decrease in thermomechanical properties was observed. Meanwhile, a molded composite with HBP showed improved mechanical properties and retention rate at 150 °C as compared to that made with neat resin. © 2015 Society of Chemical Industry
Structure of sodium sulphate aqueous solution/quartz interface: a molecular dynamics simulation

The molecular dynamics simulation was used to investigate the aqueous sodium sulphate solutions within quartz nanopores. Simulation was conducted for 13 ns to obtain the equilibrium distribution of water molecules, sulphate and sodium ions (Na+ and ) within the pores. The results clearly show an adsorption of sodium sulphate solution onto the quartz surface. However, Na+ shows a stronger attachment to the fully hydroxylated surface than due to size effects. The majority of Na+ ions appear within the primary and secondary water adsorption sites from the quartz surface. A special orientation of water molecules has been found in these layers, where one of the O–H bonds was parallel to the normal direction of the quartz surface. These observations illustrate the effect of quartz surface on the diffusion and precipitation of aqueous salt solutions under confinement, thus providing the mechanism of salt destruction on mural paintings.
Efficient Ultraviolet Organic Liquid Laser Pumped by a High Power Nitrogen Laser

An organic liquid laser pumped by a 1 MW nitrogen laser is investigated. Twenty chemical compounds which can lase at wavelengths shorter than 440 nm are examined, including six new lasing compounds. Energy conversion efficiencies are improved remarkably by high power pumping, especially in the ultraviolet. An efficiency of about 20% is obtained in the ultraviolet which is as high as in the visible region. The laser efficiency, tuning range, and some spectroscopic properties of each of these compounds are measured, and the dependence of their chemical structure on the laser characteristics is discussed in the case of scintillators represented by a general formula R1-X-R2. They are the most useful compounds for laser action in the ultraviolet.
Short‐range order and superstructures of ternary oxides AMO2, A2MO3 and A5MO6 of monovalent A and multivalent M metals related to the NaCl structure

Ternary oxides AMO2, A2MO3 and A5MO6 with monovalent A and tri-, tetra- or hepta-valent M metals can exhibit order/disorder transitions with about 20 superstructures of the NaC1 lattice. Some structures can be related to AM, A2M and A5M alloys with a larger distortion of the lattice due to stronger interactions between metal atoms. In ternary oxides about 30 short-range order configurations are selected for the first, second and third shell of metal atoms in applying Pauling's electrovalence rule. Stable configurations are characterized by the strength of Coulomb interactions and by a high point symmetry of the M atoms. Mainly disordered ternary oxides can vary stoichiometrically with a frequent occurrence of vacancies or with partial occupation of tetrahedral interstices by A atoms.