Miracle-dz/UniFAR-FTUs huggingface dataset:
Pengembangan Bahan Ajar Matematika Berbasis Integrasi-Interkoneksi Untuk Memfasilitasi Penalaran Dan Pemecahan Masalah

This research aims to produce and see the effectiveness of interconnection-based mathematics-based teaching materials to facilitate the reasoning and problem-solving skills of high school students. The method used is research model development Borg & Gall with three phases: an introduction that includes literature review and analysis of student characteristics, stage of development which include determining the basic competencies and indicators, the analysis of the materials, writing materials, and instruments, and the stage of validation includes expert validation, revision I, small group trial, analysis of the trial results, revision II, and packaging the final product. The research result is drafting a set of mathematics teaching materials based integration-interconnection effective to facilitate reasoning, and problem-solving abilities of high school students worthy with the results of the assessment of Very Good is 157.5 of the maximum score 172 or percentage 91.2% and posttest result of average mathematical reasoning 77.21 and average problem-solving ability 76.01. Also of the test is found that teaching materials can be used well in learning with positive impact. Keywords: mathematics teaching materials, interconnect integration, reasoning, problem-solving
The role of the relative voltage and phase for frequency coupling in a dual-frequency capacitively coupled plasma

Frequency coupling in multifrequency discharges is a complex nonlinear interaction of the different frequency components. An alpha-mode low pressure rf capacitively coupled plasma operated simultaneously with two frequencies is investigated and the coupling of the two frequencies is observed to greatly influence the excitation and ionization within the discharge. Through this, plasma production and sustainment are dictated by the corresponding electron dynamics and can be manipulated through the dual-frequency sheath. These mechanisms are influenced by the relative voltage and also the relative phase of the two frequencies.
Siam weed along highways, herbal medicine or poison?

The levels of five metals (Cd, Hg, Mn, Ni, and Pb) were determined in Siam weed (Chromolaena odorata) collected along Nigerian highways with a view to ascertaining the suitability or otherwise of the plant species for therapeutic purposes. Samples were acid digested and the levels of the metals in the digestates were determined using an atomic absorption spectrophotometer. The average concentrations recorded for all metals, with the exception of Cd, exceeded the maximum permissible concentrations (MPCs) of metals in natural systems for the protection of human health. It was only at the reference site that the concentrations of the five metals were within the MPC. Going by the results of this study, it is obvious that plant samples collected within the vicinity of the highways are not suitable for therapeutic purposes due to their high metals’ burdens. Therefore, for therapeutic purposes, vegetative parts of medicinal plants should be sourced at very far distances from highways to safeguard consumers of herbal medicines from toxicity associated with the ingestion of these metals.
Thermal expansion of fluorapatite-hydroxylapatite crystalline solutions

Abstract Fluorapatite has been synthesized through ion-exchange between NIST hydroxylapatite SRM 2910a and optical-grade fluorite. The latter end-member and additional intermediate F-OH apatite samples made through ion-exchange between the newly synthesized fluorapatite and the original hydroxylapatite have provided materials for an investigation of thermal expansion in the F-OH apatite system. Unit-cell volumes determined from X-ray powder diffraction data collected between 22 and 928 °C have been utilized to compute the coefficients of thermal expansion at a pressure of 1 bar for seven apatite samples having various F:OH ratios, as well as for natural samples of fluorapatite and hydroxylapatite. Results show that the thermal expansion coefficient for volume averages 41.0 ± 1.4 (1σ) × 10-6 deg-1 for all samples and is thus little affected by F:OH ratio. This study extends the thermodynamic characterization of this important mineral system, with potential applications for the geological, planetary, biological, medical, and materials-science communities.
Decolorization by ozone of direct dyes in presence of some catalysts

Abstract Decolorization of two direct dyes by ozone in aqueous medium was studied in absence and in presence of some salts at room temperature. It was found that zinc sulfate catalyses the process of decolorization. Equations to describe the process and to allow prediction of ozone requirement were developed. The new findings of this study would have an impact on wastewater treatment techniques using ozone.
In Situ Observation of CO2 Hydrate by X‐ray Diffraction

Abstract: In situ observations of CO2 hydrate growth using high‐energy X‐rays were done at high‐pressures and the growth rates of CO2 hydrate from ice particles were measured. Assuming a model of diffusion through CO2 hydrate layers, interdiffusion coefficients of CO2 and H2O molecules were calculated between 233 K and 272.5 K. The diffusion coefficient at 263 K was 7.4 × 10−16 m2/s, and the activation energy of diffusion was 0.40 eV.
Changes with time in the potassium content and phyllosilicates in the soil of the Broadbalk continuous wheat experiment at Rothamsted

The transformations of phyllosilicates and the changes in potassium (K) balances caused by long‐term cropping have been examined in soil from the 153‐year‐old Broadbalk experiment. Samples taken between 1856 and 1987 and kept in archive were fractionated for particle size and analysed for changes in mineralogy by X‐ray diffraction and changes in total K of the coarser and fine fractions. These were compared with K balances made from records of cropping and fertilizer application. No change in mica due to cropping and K‐depletion could be detected. Deep ploughing after 1925 mixed chlorite from the subsoil into the surface soil, but this had weathered by 1987. Potassium balances did not agree with measured changes in total K presumably because of unquantified uptake of K from the subsoil and poorly quantified K leaching.
Carboxylic acids-modified palm stones as sorbents for metal ions using single and multi-metal aqueous solutions

Natural palm stone has been modified in order to enhance its sorption capacity for different metal ions. The palm stone (PS), or date-pits, was treated with different carboxylic acids, namely carboxylic acid (CA), tartaric acid (TA), salicylic acid (SA), oxalic acid (OA), mandelic acid (MND) and malic acid (MA). Batch sorption tests were carried out using single, binary or tertiary metal systems composed from copper, zinc and cadmium. In single metal systems, the sorption of metal ions by modified date-pits stone was always higher than that of the unmodified date-pits. The best sorbents used in this work for the removal of Cu, Zn and Cd from their individual solution are SA-PS, CA-PS and MA-PS, respectively. For multi-metal systems, OA-PS and TA-PS can be considered as the best candidates for metal removal. Equilibrium is achieved in a contact time of about an hour. The amount adsorbed was dependent on the process conditions; it increased with an increase in pH, initial metal concentration and amount of sorbet. The Freundlich model agreed very well with the equilibrium isotherm experimental data.
Heterogeneous chemistry in the troposphere: experimental approaches and applications to the chemistry of sea salt particles

Halogen atoms, particularly chlorine atoms, are well known to be highly reactive and to play a central role in the chemistry of the upper atmosphere. A large potential source of these halogens in the lower atmosphere (troposphere) exists in the form of sea salt particles. A variety of laboratory, field and modelling studies strongly suggests that there are heterogeneous reactions of sea salt particles which generate photochemically active halogen species such as Cl in marine areas. In addition, there is increasing evidence for a contribution of bromine atoms to tropospheric chemistry in marine regions at high latitudes. We review here briefly the potential importance of such halogen reactions and evidence for their role in the chemistry of the troposphere. Studies carried out in this laboratory to elucidate, at a molecular level, the mechanisms of reaction of synthetic sea salt and its components with gases of tropospheric interest are reviewed. Initial results obtained using a new aerosol apparatus recen.
The Effects Of Differing Optical Stimuli On Depth Perception In Virtual Reality

It is well documented that egocentric depth perception is under estimated in virtual reality more often than not. Many studies have been done to try and understand why this underestimation happens and what variables aﬀect it. While this underestimation can be shown consistently the degree of underestimation can strongly diﬀer from study to study, with as much as 68% to as low as 6% underestimation, Jones et al. (2011, 2008); Knapp (1999); Richardson and Waller (2007). Many of these same studies use blind walking as a tool to measure depth perception. With no standardized blind walking method for virtual reality existing diﬀering blind walking methods may cause diﬀering results. This thesis will explore how small changes in the blind walking procedure aﬀect depth perception. Speciﬁcally, we will be examining procedures that alter the amount of ambient light that is visible to an observer after performing a blind walk.
An equation for acoustic propagation in inhomogeneous media with relaxation losses

An equation for acoustic propagation in an inhomogeneous medium with relaxation loss is systematically derived from the classical dynamic equations together with an equation of state for relaxation. The derivation assumes small acoustic perturbations but accommodates arbitrary spatial inhomogeneities in material compressibility, density, and parameters of relaxation. The linearized wave equation obtained for n relaxation mechanisms has order n + 2, is causal, and yields the expected dependence of attenuation on frequency. Exact analytic expressions valid at all frequencies are given for the spatially varying attenuation coefficient, as well as phase velocity. A Green's function is calculated for the equation. The results may be used to model scattering for image reconstruction and the determination of statistical properties, such as average differential scattering cross section.
Modelagem matemática da secagem da pimenta Cumari do Pará

Among the processes of food preservation, drying the product stands out for maintaining the nutritional quality and flavor of products. The objective of this study was to determine and adjust the curves of drying of Para Cumari pepper (Capsicum chinense Jacqui), at temperatures of 45, 55 and 65 oC. The Para Cumari peppers were collected in the city of Ceres, GO and transported to UEG - Anapolis, GO. Drying was conducted in fixed bed dryer with temperature control and airflow of 60 m3 min-1 m-2. Experimental data were adjusted to nine mathematical models. The magnitude of the coefficient of determination (R2), the mean relative error (P) and the estimated mean error (SE) were used to verify the degree of fit of the models. It was concluded that: a) the behavior of the drying curves of Para Cumari pepper was similar to most agricultural products; b) the drying time was 4 h; 2 h and 50 min and 1 h and 55 min, respectively, for the drying temperatures of 45, 55 and 65 oC; c) the mathematical model of drying proposed by Midilli et al. (2002) was the best fit to the experimental data; d) values of the diffusion coefficient increased with the increase of the temperature of the drying air, with results between 2.29 10-11 and 2.57 10-11 m2 s-1.
The Effects of Ambient Pressure Upon Global Shape and Hydrodynamic Behavior of Buoyant Laminar Jet Diffusion Flames

Abstract The action of ambient pressure variation upon buoyant laminar jet diffusion flames is studied experimentally and theoretically at low Reynolds number. For the first time, the flame height and the surface area are measured as a function of ambient pressure at different flow rates and for different burner diameters. Two distinct regimes have been found: one in which the flame flickers and the other in which it does not. For steady flames, the flame surface area increases significantly with reduction of the ambient pressure, while the height increases slightly or remains nearly constant. For flickering flames, the flame height decreases with reduction of pressure, which finally results in a decrease in the surface area of the flame. A simple theoretical model based on a cylindrical flame geometry which considers both the radial diffusion of species and the buoyancy effects, is proposed to predict the trend of surface area variation for steady flames. For steady flames, both reductions of gravity lev.
Ham Massaging. Effect of Massaging Cycle, Environmental Temperature and Pump Level on Yield, Bind, and Color of Intermittently Massaged Hams

Commercially available hams (7.69–9 kg) were open face boned, closely trimmed of fat and then stitch pumped with various levels of pickle to determine the efficacy of pump level, massage cycle, or temperature of the ham during massaging on cook shrink, USDA yield, bind, and cured color intensity and uniformity. On a constant time basis, continuous massaging appeared superior to intermittent massaging and shorter rest periods were superior to longer rest periods where intermittent massaging was used. High pump levels (30, 35%) gave correspondingly higher cook shrink losses and lower bind values (adhesion) than low pump levels. But the 35% pump level gave the best combination of cured color intensity, uniformity and yield yet still provided sufficeint bind for slice durability. Ideal environmental massaging temperatures appeared to be between 4.4°C and 10°C for maximizing cured color development and yield. Bind was reduced at 10°C; however, no problem in slice durability was experienced. SUMMARY AND CONCLUSIONS FIG. 1 SUMMARIZES the effect of factors identified in this study which influenced bind. Note that as the action time increased or rest period declined in the massaging cycles the bind increased in a linear and quadratic manner. Therefore, actual massaging time in a cycle should be long in comparison to the rest period to promote bind—such cycles also reduce cook shrinkage. Continuous massaging appears to be a better practice than intermittent massaging, provided ham tearing is not excessive. Bind decreased in a linear manner as pump levels increased, suggesting that more problems can be expected with adhesion of meat particles and slice durability as pump levels rise. Apparently, cook shrinkage also increases as pump levels rise. The effect of high environmental massaging temperature (10°C) can be considered detrimental to bind; however, since high temperatures also reduce voids and enhance cure color intensity, relatively high temperature massaging (7°C) is still recommended. Fig. 2 identifies three factors which influenced cure color intensity in a linear manner. Increasing environmental massaging temperature, higher pump level and using cycles with longer action periods and shorter rest periods, all promoted intense cure color. Increasing the action interval in the massaging cycles caused a linear increase in color uniformity of hams while temperature had no effect (Fig. 3). Increasing pump levels promoted a linear and quadratic effect on color uniformity. As high pump levels were reached the effect on color uniformity diminished. Pump levels near 35% gave good yield and cure color intensity, excellent color uniformity, and provided sufficeint bind for slice durability under the conditions of this study.
Water and Vapor Movement with Condensation and Evaporation in a Sandy Column

The diffusion of warm, humid air into an initially cold, dry, sandy column was analyzed to study the movement of water vapor and liquid water under nonisothermal and low water content conditions. The analysis was performed using the HYDRUS-1D code. While the water retention curve of sand was measured experimentally, the unsaturated hydraulic conductivity function was inversely estimated from the observed water content profiles in the column. The estimated unsaturated hydraulic conductivity function displayed a shape that reflected distinct processes of capillary pore water flow and film flow at high and low water contents, respectively. Four components of the total water flux, including thermal and isothermal liquid water and water vapor fluxes, were evaluated using the calibrated soil hydraulic properties. Evaporation and condensation rates were calculated based on water mass balance. Water vapor entered the soil column at the hot surface and condensed at the cold bottom. Subsequently, liquid water moved upward and evaporated at the moisture front in the middle of the column where the relative humidity decreased below unity. Liquid water and water vapor then circulated between the bottom and the moisture front, accompanied by condensation and evaporation processes. The impact of the enhancement factor in the thermal vapor diffusion term could not be clearly identified from available experimental water content profiles. Increases in liquid water flow and the evaporation rate could be compensated for by increases in vapor flow and the condensation rate. Additional data would be needed to fully evaluate the effect of the enhancement factor.
Solvent effect on thermal degradation of polystyrene

The thermal degradation of polystyrene (PS) in various kinds of solvents was studied in the temperature range from 300 to 450°C. The conversion of PS to low molecular weight products was dependent on the hydrogen donating ability of the solvents used: Solvents with greater donating ability resulted in less conversion of PS. A different degradation behavior was evident when phenols or other kind of solvents were used. These reaction properties are explained with a proposed degradation mechanism that includes hydrogen transfer steps from solvents to Intermediate PS radicals and from PS to the solvent radicals.
Comparative study of corrosion inhibition of aluminium alloy of type AA3003 in acidic and alkaline media by Euphorbia hirta extract

The inhibitive effect of leaf extract of Euphorbia hirta on aluminium corrosion in HCl and NaOH solutions were studied using gravimetric technique at 30 and 60°C. Results obtained showed that the leaf extract functioned as effective and excellent inhibitors in the acidic and alkaline media. Also, the leaf extract suppressed the corrosion reaction in both media. Inhibition efficiency of the extract was found to vary with concentration, temperature and exposure time. The leaf extracts of E. hirta demonstrated better inhibition efficiency in the acidic medium than in the alkaline medium. The adsorption characteristics of the leaf extract were best described by the Langmuir isotherm. Values of the free energy of adsorption G ads were determined from the isotherm parameters and they showed that the adsorption was spontaneous. The molecular interaction parameter (α) between the molecular species of the inhibitors and the metal surface they cover was also determined. The heat of adsorption (Q ads ) and apparent activation energy (E a) were estimated from the temperature dependence of inhibition efficiency. Physical adsorption mechanism is proposed from the obtained thermodynamic parameters.
Rhodomyrtals A–D, four unusual phloroglucinol-sesquiterpene adducts from Rhodomyrtus psidioides

Four novel compounds, rhodomyrtals A–D (1–4), with two unprecendented carbon frameworks of phloroglucinol coupled eudesmane, together with the known compound eucalyptin A (5) have been isolated from the leaves of the Australian plant Rhodomyrtus psidioides. The structures of compounds 1–4 were elucidated by spectroscopic analysis and ECD calculations. Some of the compounds showed good antibacterial activity against selected Gram-positive strains.
Studies of dodecanethiol capped Ag and Au nanoparticles using synchrotron radiation based photoelectron spectroscopy

Differently sized dodecanethiol capped Au and Ag nanoparticles have been investigated using synchrotron radiation based photoelectron spectroscopy (PES). Comparative measurements were also performed on self-assembled monolayers (SAMs) of dodecanethiol at vacuum evaporated Au and Ag surfaces. The series of experiments display important differences in the surface electronic and molecular structure between the different kinds of materials. Specifically, the changes measured in binding energies are discussed with respect to initial and final state effects. Also, a broadening is observed for metal-core levels in the smaller nanoparticles. Thus, surface atoms in a different chemical state than the rest of the surface atoms are detected.In valence-levelspectra,the matching between the orbitals centered at the surface-coating molecule and the orbitals centered on the core materials are discussed.
Adsorption of ammonia on the gold (111) surface

We have modeled the adsorption of ammonia on the Au(111) surface at coverages of 1/4 and 1/9 of a monolayer using density-functional theory employing the pseudopotential method, periodic imaging, a plane-wave basis set, and the PW91 density functional. The geometries of the adsorbate and the surface are fully optimized. The adsorption is found to be highly favored on top of a surface atom. Adsorption energies of 26 and 32 kJ mol−1 are obtained for the 1/4 and 1/9 of a monolayer coverage, respectively, extrapolating to 34 kJ mol−1 at zero coverage; the experimental estimate is 32–42 kJ mol−1. Small changes in the work function are predicted and interpreted as arising from a surface layer whose effective dipole moment is 2.15 D, 0.77 D larger than the calculated value of isolated ammonia. Examination of the calculated charge density and the local electric field strengths indicate that the change in dipole moment is due to polarization effects and that ammonia to gold charge transfer is minimal, at most 0.01.