Miracle-dz/UniFAR-FTUs huggingface dataset:
Laser induced defects in laser doped solar cells

Laser doping offers a promising method to define selective emitters for solar cells. Its main advantage is the localised nature of the laser beam, which allows melting of the surface area without heating the bulk. The ability to perform this process over a dielectric film offers further benefits, such as the possibility of creating self‐aligned metallisation patterns simultaneously with the selective emitter formation. However, laser induced defects, contaminations and discontinuities in the selective emitter can reduce solar cell performance. In this work the influence of different dielectric films on defect formation is investigated. It was found that a thin oxide beneath the SiNx improves the implied open circuit voltage of the solar cells for a wide range of laser output powers. Fewer defects were observed when using this SiO2/SiNx stack compared to the standard single SiNx anti‐reflection coating layer. It was also found that the recrystallised silicon layer grows epitaxially according the substrate orientation. No dislocation or stacking faults were observed in deeper areas using transmission electron microscopy, although some defects were observed near the surface. Electron beam induced current images revealed discontinuities in junctions formed with high laser powers. We conclude that micro‐cracks create these discontinuities, which can potentially induce shunts. Finally, laser doped solar cells with a standard SiNx and with a double SiO2/SiNx stack layer as anti‐reflection coating were compared. An efficiency of 18.4% on a large area commercial grade p‐type CZ substrate was achieved. Copyright © 2010 John Wiley & Sons, Ltd.
A selected-ion-flow-drift-tube study of charge transfer processes between atomic, molecular, and dimer ion projectiles and polyatomic molecules ethane, propane, and n-butane

Charge transfer processes of Ar+, Kr+, Xe+, N2+, CO+, Ar2+, Kr2+, and N4+ with the alkanes ethane, propane, and n-butane were investigated using the selected-ion-flow-drift-tube (SIFDT) technique. The relative abundances of molecular and fragment hydrocarbon product ions can be explained using the breakdown pattern of the hydrocarbon molecular ion in question and assuming that the recombination energy of the projectile ions is deposited in the quasi continuum of the energy levels of the polyatomic molecular ions in a resonant way. The observed increase of the fragment ion yields with increasing collision energy is due to collision induced excitation up to the dissociation limit of the hydrocarbon ions in collisions with the helium buffer gas atoms rather than to inelastic charge transfer from hyperthermal projectile ions.
Screening of PHA-producing bacteria using biodiesel-derived waste glycerol as a sole carbon source.

Different sources of wastewater and soil were used to screen for PHA-producing bacteria using biodiesel-derived waste glycerol as a sole carbon source by the Nile red staining method together with polymer determination. Twelve out of twenty-six isolates from biodiesel-contaminated wastewater consortium were screened for their PHA accumulation ability by cultivation in mineral salt medium supplemented with waste glycerol. The AIK7 isolate was chosen as a potential PHA producer. The PHA production on waste glycerol was examined using pure glycerol as a control substrate. The PHA content of AIK7 isolate cultivated in 10 g/L glycerol could reach 35% cell dry weight in 72 hours from waste glycerol and 33% cell dry weight in 120 hours from pure glycerol cultivation. It can be seen that at this content of waste glycerol, AIK7 isolate is effectively capable of biotransforming glycerol into polymer from low-grade glycerol.
Computational fluid dynamics studies on pasteurisation of canned milk

Pasteurisation is a vital unit operation to inactivate the spoilage organisms and enzymes present in the milk. Computational fluid dynamics (CFD) modelling can be used as a tool to determine the temperature distribution pattern inside canned milk during thermal processing. In this study, a CFD model was developed for the pasteurisation process of canned milk at 74�C and 85�C and validated with the experimental measurements. Moreover, the effect of can rotation (5, 50 and 100 rpm) on processing time and pasteurisation value was investigated. This study predicted rotation of can with 5 rpm was more effective than stationary positioned can during pasteurisation.
Energy Coupling in the PSI−LHCI Supercomplex from the Green Alga Chlamydomonas reinhardtii†,‖

Energy transfer and trapping in the PSI−LHCI supercomplex from the green alga Chlamydomonas reinhardtii have been studied using femtosecond transient absorption and picosecond fluorescence spectroscopy at room temperature. Data suggest that excitations of the PSI−LHCI supercomplex at 700 nm have similar probabilities of excitation of either the primary donor in the PSI core (absorbing at 697 nm) or low-energy Chls in the LHCI (red pigments) that presumably absorb at this spectral region. Both transient absorption and picosecond fluorescence spectroscopy indicate a biphasic overall decay of the excitation in the PSI−LHCI. The process includes a photochemical trapping in the PSI core antenna occurring with a typical lifetime of 25 ± 3 ps and a significantly slower excitation decay phase in the PSI−LHCI supercomplex occurring with a lifetime of 104 ± 20 ps and maximum of absorption changes around 685 nm. The slow excitation decay process suggests presence of an energy transfer pathway from the LHCI to the PS.
INFLUENCE OF A COOLED WALL ON DROPLET STREAM COMBUSTION

Experiments were performed to investigate combustion characteristics of droplet streams in the vicinity of a cooled wall. The droplets were composed of methanol/dodecanol mixtures or methanol. A flat-flame burner generated hot gases that were directed down an electrically heated flow tube. Droplets initially about 160 or 193 µm in diameter were injected through the center of the flat-flame burner and along the tube. The droplet stream, which ignited shortly after entering the tube, passed near a vertical flat water-cooled wall with a sharp leading edge such that the droplets were within the thermal and momentum wall boundary layers. The experiments indicate that burning rates decreased significantly when droplets were in the vicinity of the wall. The wall also influenced staged combustion behaviors of the droplet streams. In addition, flame characteristics (sooting and flame lengths) were influenced by the presence of the wall.
SYNTHESIS AND REACTIVITY IN INORGANIC AND METAL-ORGANIC CHEMISTRY

Complexes of metal ions with the flavonoids quercetin (H2L ), rutin (H2L ) and 3-hydroxyflavone (HL) have been synthesized. From the data obtained by elemental analyses, molar conductance, atomic absorption, thermal analyses, H NMR, IR, UV-Vis and EPR spectroscopies one can propose the compositions: [Cu2(L )(H2O)4]Cl2 (1), *Correspondence: Wagner F. De Giovani, Departamento de Quı́mica, Faculdade de Filosofia Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14040-901, Ribeirão Preto, SP, Brazil; Fax: 55-16-633-8151; E-mail: wfdgiova@usp.br.
Hydroiodic acid treated PEDOT:PSS thin film as transparent electrode: an approach towards ITO free organic photovoltaics

In this article, we introduce a method for fabricating highly conductive transparent poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) thin nano-structured film by treating the pristine PEDOT:PSS film with concentrated (55%) hydroiodic acid (HI). HI treatment on the pristine PEDOT:PSS film could significantly reduce the film sheet resistance without sacrificing its transparency and other electronic properties, which are highly desirable for transparent conductors. A thin layer of HI treated PEDOT:PSS film (74 nm) has very high transmittance of 90% and a low sheet resistance of 95 ohm sq−1. The sheet resistance of the film can be reduced to 37 ohm sq−1 by increasing the film thickness but at the expense of its transparency. The low sheet resistance of the film can be attributed to the increase of polarons density, conformational changes and formation of clusters due to removal of some PSS from PEDOT:PSS particles. The results were confirmed by the UV/VIS/near-IR absorption spectroscopy, atomic force microscopy, X-ray photoelectron spectroscopy and energy-dispersive X-ray spectroscopy. Given the high electrical conductivity of the HI treated PEDOT:PSS film, it was then tested as a transparent organic cathode in a polymer solar cell. This ITO-free solar cell showed superior current generation and charge collection with an efficiency of 5.83%, which is 18 times higher than the cell that used untreated PEDOT:PSS film. We, therefore, envisage this potential fabrication method, which uses HI acid, to be applied on other conjugated polymers to enhance their conducting properties for practical applications.
Studies in recombination and dissociation reactions for collisional energy transfer and electron transfer of nanocrystals and dye molecules

This dissertation consists of three parts. In the first part, the effect of the large impact parameter near-elastic peak of collisional energy transfer for unimolecular dissociation/bimolecular recombination reactions and deviation from equilibrium case is studied. To this end the conventional single exponential model, a bi-exponential model that fits the literature classical trajectory data better, a model with a singularity at zero energy transfer, and the most realistic model, a model with a near-singularity, are fitted to the trajectory data in the literature. A theory is developed for the population distribution as a function of the energy E of a dissociating model, and used to calculate the three-body low pressure recombination rate constant. In the second part, the electron transfer process in the single quantum dot fluorescence blinking phenomenon is studied. The DCET (diffusion controlled electron transfer) model has been modified to explain the exponential cutoff of the power law time distribution of the bright state and the quadratic dependence of the exponential tail on the excitation intensity. Based on ensemble measurements it is proposed that an exponential tail for the dark state time distribution for long time experiments exists for single trajectory experiments. In the last part, we develop a general MLE (maximum likelihood estimation) method to analyze experimental data with a potential distribution of power law form which can be extended to a power law with an exponential tail and more generally, many other distribution forms.
Comparison of Immunoassay and HPLC for Analyzing Fluridone Concentrations: New Applications for Immunoassay Techniques

ABSTRACT High performance liquid chromatography (HPLC) and an enzyme-linked immunosorbent assay (ELISA) technique were used to analyze concentrations of the aquatic herbicide fluridone (l-methyl-3 phenyl-5-[-3 (trifluromethyl) phenyl]-4 (IH) pyridinone) in 488 surface water samples collected from two lakes in Michigan treated in 1997, 2 Michigan lakes treated in 1998, 1 lake in Florida treated in 1996, and a series of research ponds treated in Florida in 1997. Samples were collected following application of fluridone associated with operational treatment programs that targeted the exotic submersed plants Myriophyllum spicatum L. (Michigan) and Hydrilla verticillata (L.f) Royle (Florida). ELISA and HPLC results compared well (r2 = 0.84 to 0.98) across a broad range of initial fluridone treatment rates (5 to 150 μg L−1). The potential use of ELISA to monitor fluridone residues in the water in near real-time, and to use this residue data for lake specific herbicide treatment recommendations represents a unique use of ELISA technology.
FOLIAR FERTILIZATION ON PINEAPPLE QUALITY AND YIELD

There are just a few studies using foliar sprays with micronutrients on pineapple crops. The objective of this study was to evaluate the B and Zn effect, as chelate, acid or salt, via foliar feeding, on fruit yield and quality. The experiment was carried out in Guaracai, Sao Paulo State, Brazil, in a loamy medium texture soil, by using Smooth Cayenne (Hawaiian) pineapple seedlings. A randomized block design with four replications was adopted, with 110 g ha-1 of B and 250 g ha-1 of Zn for each application. Two foliar sprays were applied, at 7 and 9 months after planting. The B and Zn sources did not affect the total soluble solids contents, titratable acidity, average fruit diameter, fruit length without crown, and maturity index. Only the B, Zn, and K concentrations in the leaves were influenced by the application of micronutrients.
The Synthesis of Four New Unsymmetrical Vic-Dioximes and Their Complexes with Some Transition Metals

Abstract In this study, anti-p-tolylchloroglyoxime (PTCGH2) has been synthesized by chlorination of anti-p-tolylalyoxime. The reaction of PTCGH2 with suitable arylamines in ethanol between -10°C and -15°C gives unsymmetrical vic-dioximes. namely, o-toluidino-p-tolylglyoxime (C16H17N3O2), 1-naphthylamino-p-tolylglyoxime (C19H17N3O2), 1,1′-biphenyl-4-amino-4′-amino-p-tolylglyoxime (C21H20N4O2), N-(2-methylpyridyl)amino-p.-tolylglyoxime (C15H16N4O2). The Cu(II) and Ni(II) complexes of these ligands are square-planar while the Co(II) complexes are octahedral with water molecules as axial ligands. 1H-NMR, mass and IR spectra and elemental analyses data are given.
Quantum chemistry on the time axis: electron correlations and rearrangements on femtosecond and attosecond scales

ABSTRACT Recent developments toward the production and laboratory use of pulses of high intensity, and/or of very high frequency, and/or of ultrashort duration, make possible experiments which can produce time-resolved data on ultrafast transformations involving ‘motions’ of electrons. The formulation, quantitative understanding and prediction of related new phenomena entail the possibility of computing and applying solutions of the many-electron time-dependent Schrödinger equation, for arbitrary electronic structures, including the dominant effects of Rydberg series, of multiply excited states and of the multi-channel continuous spectrum. To this end, we have proposed and applied to many prototypical cases the state-specific expansion approach (SSEA). The paper explains briefly the SSEA and outlines four of its applications to recently formulated problems concerning time-resolved electronic processes, where electron correlations are crucial. These are as follows: (1) the time resolution of the decay of polyelectronic unstable states, (2) the excitation and decay of strongly correlating doubly excited states and atto-time-resolution of their geometries, (3) the time-resolved process of formation of the interference profiles of resonance states during the femtosecond photoionisation of helium and aluminium, and (4) the relative time delay in the (2s, 2p) photoionisation of neon by an attosecond pulse.
Acid-Treated Montmorillonites—A Study by 29Si and 27Al MAS NMR

Abstract The JP (Jelšový Potok, Slovakia) and SWy-1 (Wyoming, USA) montmorillonites were treated in 6 m HCl at 95°C. The rates of dissolution of tetrahedral and octahedral Al (Altet and Aloct) are comparable. Aluminium in the tetrahedral sheets was also identified in both untreated samples by 29Si MAS NMR spectroscopy. About 12% of total Si in SWy-1 was found to be bound in quartz. Traces of undecomposed montmorillonite and a small amount of Altet in the three-dimensional SiO4 framework were found in the reaction product of montmorillonite decomposition. Three different types of structural units were identified in acid-treated samples: Q4(OAl) units of amorphous silica with three-dimensional crosslinked framework; (SiO)3SiOH units, remaining as a result of poor-ordering of the framework without the possibility of cross-linking; and Q4(1A1) units.
Comparative studies on physicochemical and baking properties of newly harvested and stored indian varieties of wheat

Comparative studies on the progressive changes in distribution pattern of proteins, and in rheological and baking properties, were carried out with seven newly harvested and stored wheat varieties. Freshly harvested wheat contained a larger amount of low molecular weight gliadins, which were aggregated during storage in air. This resulted in improvement of the rheological and baking properties of stored grains. Thus, gluten content in wheat or, more precisely, the interchange reactions between thiol and disulphide during storage, governed the dough rheology. The same effects could be achieved by addition of an oxidising agent such as KBrO3. Radiation treatment (up to 200 krad) also improved the baking quality of newly harvested wheat by modifying some of its rheological properties. A significant correlation between SS/SH ratio and loaf volume was observed. Lower loaf volume in newly harvested wheat was associated with its low SS/SH ratio, high maximum gelatinisation viscosity and low gas retention capacity.
An Assessment of the Surface Properties of Milled Attapulgite Using Inverse Gas Chromatography

The most common means of reducing the particle size of solids is by grinding, a process which can affect the surface properties and the behavior of the solid in later stages (granulation, compaction, etc.), and which can influence the end-use properties of the final product. Inverse gas chromatography (IGC) measurements were used here to evaluate the influence of grinding, in a ball mill, on attapulgite. The milling experiments were performed in dry media for various periods. After 30 min of grinding, significant decreases in the particle size and specific surface areas were observed when calculated using different probes. No noticeable variation in the surface properties was observed by IGC either at infinite dilution or at finite concentration, however. In particular, the distribution functions of the adsorption energies (DFAE), giving information about the surface heterogeneity for both an apolar probe (octane) and a polar probe (isopropanol), remained unchanged, regardless of the grinding time. The stability of the surface energy with respect to the grinding process was seen to be related to the particular fibrous structure of the attapulgite clay.
An Inexpensive Multilevel Array of Sensors for Direct Ground Water Velocity Measurement

The point velocity probe (PVP) is an instrument capable of measuring ground water velocity in situ at the centimeter scale. It is based on detecting an electrically conductive tracer transported by ground water around the perimeter of the cylindrical probe. PVPs are easily constructed from inexpensive materials and can be deployed as a single sensor or in multilevel arrays. A multilevel array of these instruments, consisting of four PVPs stacked vertically on each of five stands, was installed as a fence within a sheet‐pile alleyway at the Canadian Forces Base Borden test site in Ontario, Canada. The data from the fence revealed notable velocity variations both spatially and temporally. Ground water velocity data of these kinds are likely to be valuable for permeable reactive barrier design and assessment, regulatory compliance assessments, and a variety of research level investigations concerned with local flow phenomena.
Patterns of Needle-Plane Discharges in Electronegative Hydrocarbons

Some of our previous experimental work focused on corona discharges in hydrocarbon media. It has been shown that the discharge can be characterized by corona “impedance. ” The present article elaborates on this work and introduces complementary details. In a negative pin-to-plane geometry, the experiments show that a corona parameter exhibits quasi-linear variation with corona current. The discharge was studied in a medium with controlled pressure, temperature, and homogeneity of the sample. The results were reproducible on different concentrations of the hydrocarbon mixture used. A modeling of the observed phenomenological relation is discussed. It is believed that the present analysis can be useful in optimizing characteristics of pin-plane corona discharges in hydrocarbon media.
Synthesis, Structure, Molecular Orbital and Valence Bond Calculations for Tetrazole Azide, CHN7

The synthesis, NMR spectroscopic characterization and structure determination of highly explosive tetrazole azide, a very nitrogen-rich material (88.3% N) is reported. Tetrazole azide was prepared in high yield from the diazotation reaction of aminotetrazole, followed by treatment of the formed diazonium salt with sodium azide. Synthesis in diethylether/methanol and recrystallization from diethylether afforded colorless cubes: CHN7 (1): monoclinic, P1 21/n1, a=1346.6(5), b=499.6(2), c=1360.9(5) pm, β=105.14(1)0, V=0.884(2) nm3, Z=8, ϱ=1.670 g cm−3. The observed structural parameters (X-ray) are in good accordance with the results from molecular orbital (MO) calculations. The computed electrostatic potential (B3LYP) suggests a pronounced shock and friction sensitivity which was confirmed experimentally. Quantitative valence bond (VB) calculations were performed for the most important 21 VB structures in order to obtain the structural weights and to obtain an assessment for the importance of the various individual VB structures considered.
Microbial biomass and nitrogen transformations in surface soils strongly acidified by volcanic hydrogen sulfide deposition in Osorezan, Japan

Abstract Volcanic acidification has created unique ecosystems that have had to adapt to the acidic environments in volcanic regions. To characterize the primary microbial properties of strongly acidified soils in such environments, we investigated microbial biomass, nitrogen transformations and other relevant chemical properties in the surface soils of solfatara and forests from Osorezan, a typical volcanic region in Japan, and compared the results to common Japanese forest soils. Soil microbial biomass C (MBC) and N (MBN) were determined using the chloroform fumigation–extraction method. Potential net N mineralization and net nitrification were measured in aerobic laboratory incubations. Long-term acidification in the Osorezan soils by volcanic hydrogen sulfide deposition caused low soil pH (3.0–3.8), base cation deficiency and increased concentrations of toxic ions such as Al3+. The proportions of MBC to total carbon (MBC/TC ratio) and MBN to total nitrogen (MBN/TN ratio) were lower than those in common Japanese forest soils. The extreme acidic conditions may have inhibited microbial survival in the Osorezan acid soils. Net N mineralization occurred at rates comparable to those in common Cryptomeria japonica forest soils, probably because of the presence of acid-tolerant soil microorganisms. Net nitrification was completely inhibited and autotrophic ammonia oxidizers were not detected by the MPN method. The inhibition of nitrification prevents nitrogen leaching from the soils, thus maintaining a nitrogen cycle in the volcanic acid region in which NH+ 4 (and NH3) is recycled among microorganisms and plants.
A UV-Visible Study of Partitioning of Pyrene in an Anionic Surfactant Sodium Dodecyl Sulfate

The interaction of hydrophobic dye pyrene with sodium dodecyl sulphate (SDS), an anionic surfactant, was studied in the process of solubilization. Difference UV-Visible spectroscopy was used to carry out the study. The partition coefficient (Kx), and number of dye molecules incorporated per micelle (n) was calculated. High Kx value shows that pyrene is partitioned strongly from polar to nonpolar environment. Steady-state fluorescence spectroscopy is used to check the environment of the pyrene as it is a well-known fluorescent probe. Onset of slope in curves is used to determine the critical micelle concentration (CMC).