Miracle-dz/UniFAR-FTUs huggingface dataset:
Crystallographic texture and microstructure of terebratulide brachiopod shell calcite: An optimized materials design with hierarchical architecture

Abstract We analyzed the microstructure, microchemistry, and microhardness variations across the architectural elements of the shells of the brachiopod species Megerlia truncata and Terebratalia transversa with scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), laser-ablation inductively coupled plasma mass-spectrometry (LA-ICP-MS), and Vickers microhardness indentation (VMHI). The brachiopod valves consist of two principal layers of distinct calcite biomineralization: a thin, nanocrystalline, outer, hard protective layer with VMHI values exceeding 200 HV and a much thicker, inner, secondary layer of a hybrid organic-inorganic fiber composite material. The secondary layer is further structured into two sublayers, an outer part with VMHI values varying between 110 and 140 HV, and a softer inner part (70 < HV < 110). Whereas the size of the calcite crystals within the primary layer varies between a few tens of nanometers and 2 μm, calcite crystals within the secondary layer are fibrous, commonly reaching lengths exceeding 150 μm. Cross sections of these fibrous crystals are spade shaped, their dimensions being about 5 × 20 μm. The fibers are aligned parallel to each other. They are single crystals with their morphological fiber axes pointing almost parallel to the shell vault. The crystallographic orientation of the morphological fiber axes, however, is arbitrary within the a-b plane of the calcite lattice, whereas the c-axis (hexagonal unit-cell setting) is perpendicular to the morphological fiber axes and thus parallel to the radial vector of the valve vault. This morphology strongly indicates that fibrous growth is controlled by confinement within a cell in an organic matrix and not by attachment of biomolecules to specific crystallographic faces. We observe inhomogeneous Sr2+ and Mg2+ concentrations in the shell calcite within the 0.1. 0.9 wt% range. Design of the shell appears to be highly optimized for mechanical performance. Crystal morphology and orientation as well as incorporated organic matter are structured hierarchially at different length levels forming a hybrid organic-inorganic fiber composite architecture.
Parâmetros agronômicos do sorgo em razão de estratégias de semeadura e adubação

Objetivou-se com esta pesquisa avaliar estrategias de semeadura e adubacao com NPK nos parâmetros agronomicos do sorgo forrageiro e granifero . No experimento I foi utilizado o sorgo forrageiro AG-2002 e os tratamentos avaliados foram tres doses do formulado NPK 10-20-10 (18, 25 e 32 g m -1 linear) e dois espacamentos entre linhas de 60 e 80 cm, com quatro repeticoes. Notou-se interacao significativa do espacamento x adubacao no diâmetro de colmo e produtividade de panicula do sorgo forrageiro, destacando-se a associacao de 25 e 32 g de NPK no espacamento de 60 cm entre linhas (7,64 e 8,40 t ha -1 de panicula, respectivamente). A altura media das plantas e a produtividade de materia verde aumentaram quando as maiores doses de NPK foram empregadas. Na conducao do experimento II, estudou-se o sorgo granifero DKB550 e os tratamentos avaliados foram tres espacamentos entre linhas 50, 70 e 90 cm e duas densidades de plantio de 10 e 12 plantas por metro linear, com quatro repeticoes. A altura media de plantas, produtividade de materia verde e produtividade de panicula foram maiores quando a densidade de plantio foi maior (12 plantas m -1 ). A produtividade e porcentagem de paniculas em relacao a planta inteira foram maiores quando manejados no menor espacamento entre linhas de 50 cm. O sorgo forrageiro respondeu de forma positiva a adubacao com NPK, melhorando os parâmetros agronomicos. Plantios mais adensados resultam em melhores caracteristicas agronomicas, principalmente, em relacao a produtividade de paniculas.
Ultrastructural changes in a holocellulose pulp revealed by enzymes, thermoporosimetry and atomic force microscopy

Abstract To increase our knowledge of the ultrastructure within softwood fibres, enzymatic treatment, thermoporosimetry, light microscopy, and atomic force microscopy with image analysis were used to investigate the structure of holocellulose softwood pulp fibres. The size of the average cellulose fibril aggregates and the width of pore and matrix lamellae were found to be uniform across the secondary cell-wall layer in the transverse direction of the wood fibre wall. In holocellulose, these dimensions were very similar to those in the native wood, whereas in kraft pulp the cellulose fibril aggregates were larger and the pore and matrix lamellae broader. These differences between holocellulose and kraft pulp fibres suggest that a high temperature is needed for cellulose fibril aggregation to occur. Neither refining nor drying of the holocellulose pulp changed the cellulose fibril aggregate size. Upon drying and enzymatic treatment, a small decrease in the pore and matrix lamella width was evident throughout the fibre wall. This indicated not only uniform distribution of pores throughout the fibre wall, but also enzymatic accessibility to the entire fibre wall. The holocellulose pulp had a somewhat larger pore volume than the kraft pulp. Refining of the holocellulose pulp led to pore closure, probably due to increased mobility of the fibre wall. The enzymatic treatment revealed that during hydrolysis of one hemicellulose, part of the other was also dissolved, indicating that the two hemicelluloses are to some extent linked to each other in the structure.
FIVE-YEAR CURRICULUM OF TEACHER EDUCATION IN THAILAND; GAIN OR PAIN?

The purposes of the study were to (1) explore the advantages or disadvantages of five-year curriculum of teacher education program in English, General Science, Math, Thai, Social study and Early childhood Education, Faculty of Education, Suan Sunandha Rajabhat University, and (2) to explore participants’ opinion whether the participants prefer five-year curriculum of teacher education to four-year curriculum of teacher education and why. The research sample, selected by volunteer sampling technique, comprised 12 internship student teachers program in English, General Science, Math, Thai, Social study and Early childhood Education, Faculty of Education, Suan Sunandha Rajabhat University. The data collection was conducted by using semi-structured interview which covered 2 main questions. The qualitative data analysis was conducted with the data obtained from semi-structured interview. It was found that there are both advantages and disadvantages of five-year curriculum of teacher education. The main advantage was providing one-year internship and disadvantages were describe in many aspects. Student teachers’ selection of teacher education curriculum were both five-year and four-year curriculum with different reasons.
Characterisation of poly(ethylene terephthalate) and cotton fibres after cold SF6 plasma treatment

Poly(ethylene terephthalate) (PET) and cotton fibres, treated in an appositely set up RF SF6 plasma reactor under different operating conditions, were characterised by XPS, EPR, DSC, XRD, ATR analyses, water contact angle and water droplet roll-off angle measurements. The ageing of plasma-treated samples was also investigated under different post-treatment conditions. Plasma treatment led to efficient implantation of fluorine atoms on the surface of both polymers; this resulted in water repellence without altering the bulk properties of the polymers. The radical species formed in the plasma-activated polymer surface were involved in its fluorination and in the subsequent uptake of atmospheric oxygen. Surface reorganisation of polymer segments, tending to reduce the interfacial energy between the polymer and the phase in contact with it, induced the surface modifications observed under ageing and in samples plasma-treated several times. An increase in the depth of the fluorinated layer, leading to outstanding stable hydrorepellence, was achieved by repeated SF6 plasma treatments, followed by surface rearrangements favoured by swelling.
PbS-Quantum-Dot-Based Heterojunction Solar Cells Utilizing ZnO Nanowires for High External Quantum Efficiency in the Near-Infrared Region

The improvement of solar cell performance in the near-infrared (near-IR) region is an important challenge to increase power conversion efficiency under one-sun illumination. PbS quantum-dot (QD)-based heterojunction solar cells with high efficiency in the near-IR region were constructed by combining ZnO nanowire arrays with PbS QDs, which give a first exciton absorption band centering at wavelengths longer than 1 μm. The morphology of ZnO nanowire arrays was systematically investigated to achieve high light-harvesting efficiency as well as efficient carrier collection. The solar cells with the PbS QD/ZnO nanowire structures made up of densely grown thin ZnO nanowires about 1.2 μm long yielded a maximum incident-photon-to-current conversion efficiency (IPCE) of 58% in the near-IR region (@1020 nm) and over 80% in the visible region (shorter than 670 nm). The power conversion efficiency obtained on the solar cell reached about 6.0% under simulated one-sun illumination.
The kinetics of solid-phase microextraction measured for freshly added and aged hydrophobic compounds in two different soils

The proper choice of exposure times is critical if the freely dissolved concentration of chemicals in soil porewater is to be measured via the equilibrium solid-phase microextraction (SPME) as the times to equilibrium may vary depending on compound and soil properties. To reveal the effects of compound hydrophobicity, ageing and soil organic matter content on times to equilibrium, the SPME uptake was measured for five freshly added and aged hydrophobic organic compounds (phenanthrene, pyrene, lindane, p,p′-DDT and polychlorinated biphenyl (PCB) 153) in two contrasted soils (arable and forest soil). The tested compound-soil systems behaved kinetically different. Longer equilibrium times were observed with increasing hydrophobicity of compounds for aged compared to freshly added chemicals and for the forest soil in comparison to the arable soil. The calculated soil–porewater partition coefficients (i.e. sorption coefficients, Kd) of chemicals differed between soil types mainly due to various organic carbon (OC) contents as evidenced by the comparable Koc values (i.e. Kd values normalised to soil OC content). Similar Koc values were also found with the various extent of ageing, indicating that both the freshly added and aged compounds linearly partitioned between the soil organic matter and porewater. Our results suggest that, for a respective compound, variations in equilibrium times may be expected depending upon the residence time and the organic matter content in soil where the longest equilibrium times seems to appear for a combination of aged compounds and high organic soils. With regard to this outcome, the effect of the level of sample depletion due to the SPME extraction (LDSPME) on equilibrium times was assessed. At LDsSPME of up to 10%, equilibrium times increases linearly with LDsSPME for p,p′-DDT and PCB 153. For phenanthrene (LDSPME<10%), and for lindane and pyrene (1.2% < LDSPME > 40%), no clear relationships were observed.
FREQUENCY-DEPENDENT OPTICAL CONSTANTS OF WATER ICE OBTAINED DIRECTLY FROM AEROSOL EXTINCTION SPECTRA

We report here a new approach for determining frequency-dependent real and imaginary components of the refractive index of crystalline solids directly from the observation of the infrared spectra of the corresponding aerosols. The interplay between scattering and absorption observed in large (> 0.5-pm-radius) particles allows us to properly scale the imaginary component, determined from the absorption spectrum of small (around 0.3-pm-radius) aerosols, using calculations based on the Mie scattering theory. Once the imaginary indices are properly scaled, the corresponding real indices are determined through a Kramers-Kronig analysis. The method is applied to the study of water ice aerosols, and comparisons with previous measurements confirm that the method is sound and accurate, Reported here is a detailed study of the temperature dependence of the refractive index of ice. Experiments are reported over the temperature range from 130 to 210 K, which includes the region of interest for the study of polar stratospheric clouds (PSC’s).
Chemical changes during the alteration of micas

Abstract Di- and trioctahedral micas were altered to vermiculite-like minerals by extracting the K with sodium tetraphenylboron. Chemical analysis of original and altered micas shows that loss of K is accompanied by an increased loss on ignition, oxidation of some Fe2+ to Fe3+, loss of divalent octahedral cations, mainly Mg2+, loss of OH− (or sorption of H+) and decrease in net negative charge. The following reactions are suggested to explain these changes: (1) replacement of K by Na at interlayer sites; (2) release of structural OH− ions exposed by replacement of K, which decreases the negative charge and allows the structure to expand and more K to be replaced; (3) oxidation of Fe2+ ions by the reaction 4Fe2+ + 4 structural (OH−) + O2 → 4Fe3+ + 4 structural (O2−) + 2H2O; and (4) release of divalent octahedral ions, possibly through some of the holes left when structural OH− is lost. The wide implications of these proposals are discussed.
Analysis of the stress-strain relationships in reactor grade graphite

Departure from linearity in the stress-strain relationships and plastic deformation are observed in reactor grade graphite at very small stresses. A model is put forward which describes the mechanical behaviour of such a material and a simple mathematical theory is derived which is shown to give an adequate description of the stress-strain relationships of graphite on stress cycling under low compressive stresses.
Water soluble inorganic trace gases and related aerosol compounds in the tropical boundary layer. An analysis based on real time measurements at a pasture site in the Amazon Basin

This dissertation investigates the behavior of water-soluble inorganic trace gases and related aerosol species in the tropical boundary layer. Mixing ratios of ammonia (NH3), nitric acid (HNO3), nitrous acid (HONO), hydrochloric acid (HCl), sulfur dioxide (SO;,) and the corresponding water-soluble aerosol species, ammonium (NH,,1), nitrate (NO3 ), nitrite (NO,), chloride (CI) and sulfate (SO,") were measured at a pasture site in the Amazon Basin (Rondonia, Brazil). Sampling was performed from 12 Sep. to 14 Nov. 2002, covering the late dry (biomass burning) season, the transition period and the onset of the wet season (clean conditions) (LBA-SMOCC*). Measurements were made continuously using a wet-annular denuder (WAD) in combination with a Steam-Jet Aerosol Collector (SJAC) followed by on-line analysis. Real-time data were combined with measurements of the aerosol compounds sodium (Na+), potassium (K), calcium (Ga ), magnesium (Mg2) and low-molecular weight polar organic acids determined using integrated filter samples. Additionally, on-line measured mixing ratios of nitric oxide (NO), nitrogen dioxide (NTX) and ozone (O3) as well as (microj-meteorological quantities are considered, Gaseous NH3 was present in mixing ratios an order of magnitude higher than those of HN0:i, HONO, HCl and SO,. Thermodynamic equilibrium models are used to explore the impact of mineral cations (particularly pyrogenic K+) and LMW polar organic acids on the NH4+-NO3"-C1 -SO. ," -H2O aerosol system. Mineral cations present in Amazonian fine mode aerosols significantly balanced aerosol NO.," and SO/ during daytime and (NH4)2SOj appeared to be only a minor aerosol component. Thermodynamic equilibrium permitted the formation of aqueous ? ,,? ;, and NH^Cl only during nighttime at RH>90 %. During daytime, excess NH3 neutralized LMW polar organic acids, forming aerosol NRy. Local dry and wet deposition rates of inorganic ? are presented. Dry ? deposition was inferred using the "big leaf multiple resistance approach" and a canopy compensation point model. Dry ? deposition is dominated by NH:i and NO3, which featured highest mixing ratios as a consequence of biomass burning activities during the dry season. The pasture site was likely to have a strong potential for daytime NH3 (re-) emission, owing to high canopy compensation points, which are related to high surface temperatures and to direct NH^ emissions from cattle excreta. Total (dry + wet) ? deposition was estimated to be 7.3 - 9.8 kgN ha"1 yr"\\ which exceeds predictions for the Amazon region by global chemistry and transport models by at least factor of two.
Study of substrate bias effect on corrosion susceptibility of thin film magnetic disks by accelerated chemical tests

In this study, the characteristics of two relatively fast pore decoration techniques used for studying corrosion susceptibility of thin film disks with the structure CoCrTa/Cr/NiP/AlMg are discussed. The first technique employs HCl vapor. Since the HCl vapor reacts with both the cobalt alloy and the NiP layers, it has the capability of revealing pores in the sputtered layers with different sizes and depths that have an opening at the disk surface. The other technique uses a concentrated nitric acid solution. Because concentrated nitric acid reacts only extensively with the NiP layer, it is used to reveal the deeper pores in the sputtered layers with depth reaching the NiP layer. The tests are used to study the corrosion susceptibility of thin film disks with different substrate bias voltages during growth of the magnetic and chromium layers. By the use of these two accelerated chemical tests, the pinhole densities of sputtered films are found to decrease with increasing bias due to ion bombardment on the .
APPLICATION OF A METAL SOLUBILITY MODEL TO GEOCHEMICAL SURVEY DATA

In areas where heavy metals are introduced into or onto land where they would not normally be present at elevated concentrations, then that land could be considered to be contaminated. A simple way of determining the magnitude of contamination by heavy metals is to measure the total metal concentration in the soil. However, this simple measure is a poor way of assessing the potential risks to the environment and human health. A more effective risk assessment can be achieved by analysing the proportion of the total metal that exists in a mobile or bioavailable form, in other words, the metal solubility. Unfortunately metal solubility is more difficult and costly to measure than total metal concentration in the soil. This thesis examines the application of a metal solubility model to geochemical survey data consisting of pH and metal concentrations. The solubility predictions were interpolated in order to produce maps; however, the interpolated data had very high uncertainties. Further analysis showed that pH was the greatest source of uncertainty in the algorithm, contributing the most for lead, with 76% of the uncertainty being due to pH. pH was least influential for copper, contributing 49% of the uncertainty, but pH was the highest contributor in each metal. In order to examine the accuracy of the algorithm without geostatistical influences, a field work study was undertaken to measure metal solubility directly at the original survey sites. This showed that the algorithm was very good at predicting metal solubility at point sources. In order to assess the shortscale spatial variability of pH, and the errors in pH measurements, a second field work project was conducted, measuring the pH on 200 samples from a single field. This work showed that pH does vary across a field, but more importantly allowed a quantification of the uncertainty involved in sampling and measuring pH. Results show that despite the short-scale variability in pH, point predictions are accurate (the average difference between measured and predicted pZn2+ is 6%), xvi and might be of use to land managers. However, interpolating solubility predictions for mapping produces unacceptably high uncertainties (mean values were 188% for Pb, 417% for Cu and 153% for Zn) for land management or the development of policy measures related to soil. Further work could include calculating the measured Pb and Cu solubility and comparing these to the predictions. A study to investigate how pH and Zn2+ vary together across a field would also be of interest.
Sequential Fractionation of Copper, Lead, Cadmium and Zinc in Soils from or near Doñana National Park

A knowledge of the total amount of truce metals is not enough to assess the environmental impact of polluted soils. For this reason, the determination of metal species in solution is important to evaluate their behavior in the environment and their mobilization capacity. Soils contaminated by Cu, Pb, Cd, and Zn found at Donana National Park (Spain) were examined for total content. Sequential extraction schemes were used to determine the degree of pollution and to partition the trace elements in soils. The three areas studied (marshes, stabilized sand, and mine) have different contamination levels. The northern-most marshes of Donana National Park have the highest total levels of the four metals due to the influence of a mine located 40 km away
Description of tunneling with the help of coupled frozen Gaussians

A previous initial value coherent state representation is applied to Gaussian wave packet propagation on one-dimensional and two-dimensional double well potentials. The method uses a basis of trajectory guided frozen Gaussian coherent states, sampled from a Monte Carlo ensemble, for numerical solutions of the quantum time dependent integro-differential Schrodinger equation. Accurate tunneling splittings are obtained. Comparisons are also made with corresponding results obtained by the Herman–Kluk semiclassical initial value representation wave packet method.
Molecular simulations of physical and chemical adsorption under gas and liquid environments using force field- and quantum mechanics-based methods

Here we review our simulations of adsorption on metal–organic frameworks (MOFs) and platinum (Pt) catalysts, focusing on the modelling methods required to understand these two very different systems. MOFs are porous, crystalline materials with large surface areas, which are promising for a variety of adsorption applications. We review our simulations of gas uptake in PCN-53 (porous coordination network) as well as gas storage in MOFs functionalised with metal alkoxide sites. While fluid–solid interactions in both systems can be modelled quite well using algebraic force fields, the alkoxide sites in the functionalised MOFs require specialised versions, in order to describe the stronger adsorption energies. We discuss grand canonical Monte Carlo (GCMC) simulations of both systems. Pt is a common catalyst, and simulations have proven quite useful for providing molecular level details to understand its functionality. This involves understanding adsorption phenomena, which often requires quantum mechanical calculations. We describe our periodic boundary condition density functional theory (DFT) simulations of Pt-catalysed NO oxidation, focusing on adsorbate geometries and coverage effects. Finally, we describe one of the current ‘grand challenges’ in molecular simulations of adsorption, modelling catalytic activity in aqueous phase, which requires a combination of algebraic force fields, DFT and GCMC.