Miracle-dz/UniFAR-FTUs huggingface dataset:
Synthesis and optical properties of novel organic–inorganic hybrid UV (R–NH3)2PbCl4 semiconductors

We report on the synthesis and the optical properties of several novel ultraviolet (UV) semiconductors (R–NH3)2PbCl4. These semiconductors are two dimensional organic–inorganic perovskite (2DOIP) materials and have multiple quantum-well energy level structures. We systematically varied the organic components (R–NH3+), and discussed their influence on the self-organization ability, excitonic optical features, and long-term photo-stabilities of the 2DOIPs. The trends of selecting the organic groups to tailor the optical features and to improve the self-organization and long-term photo-stabilities of 2DOIPs are obtained by analyzing the experimental results. Self-organization abilities are found to be highly dependent on the interactions among the organic components. The excitonic optical properties of 2DOIPs are found to depend more on the steric structures, and less on the electronic structures and chemical properties of the organic groups (R–NH2) as long as the organic groups are optically inert. However, the long-term photo-stabilities of the (R–NH3)2PbCl4 semiconductors are highly dependent on the thermal and photo stabilities of organic components. We find a new UV semiconductor, (C6H11CH2NH3)2PbCl4 (CMPC), which has better photo-stability than the usually used (C6H5C2H4NH3)2PbCl4 (PEPC).
Influence of nitrogen on magnetic properties of indium oxide

Magnetic properties of indium oxide (In2O3) prepared by the decomposition of indium nitrate/indium hydroxide in the presence of ammonium chloride (NH4Cl) has been investigated. Structural and optical characterizations confirm that nitrogen is incorporated into In2O3. Magnetization has been convoluted to individual diamagnetic paramagnetic and ferromagnetic contributions with varying concentration of NH4Cl. Spin wave with diverging thermal exponent dominates in both field cool and zero field cool magnetizations. Uniaxial anisotropy plays an important role in magnetization as a function of magnetic field at higher concentration of NH4Cl. Avrami analysis indicates the absence of pinning effect in the magnetization process. Ferromagnetism has been interpreted in terms of local moments induced by anion dopant and strong hybridization with host cation.
Computational fluid dynamics simulation of mixing characteristics and light regime in tubular photobioreactors with novel static mixers

BACKGROUND Tubular photobioreactors are considered to be important and potential photobioreactors due to their higher photosynthetic efficiency and biomass productivity. In this work the performance of a new tubular photobioreactor with novel static mixers on mixing characteristics and light regime was studied through computational fluid dynamics. RESULTS The effects of cross-angle of two blades, horizontal spacing, open porosity and hole radius of the novel static mixers on mixing characteristics were investigated to obtain appropriate configurations. Compared with the tubular photobioreactor without static mixers, the tubular photobioreactor with novel static mixers was proved to have strong fluid mixing and significant swirling flow. Average velocity magnitude along the light direction increased by nearly 1000 times and turbulent kinetic energy increased by 1.3 times after adding novel static mixers into the tubular photobioreactor. Additionally, with novel static mixers most cells were promoted to circulate between the light zone and the dark zone. The light/dark cycle frequency was also improved and increased by 85.21% and 95.77% at fluid inlet velocity of 0.3 and 0.4 m s−1, respectively. CONCLUSION The simulation results showed the novel static mixers could effectively enhance mixing degree of fluid and increase the light/dark cycle frequency of microalgal cells in tubular photobioreactors. © 2014 Society of Chemical Industry
Joint Coordinate Optimization in Fingerprint-Based Indoor Positioning

Fingerprint-based indoor positioning uses pattern recognition algorithms (PRAs) to estimate the users’ locations in wireless local area network environments, where satellite-based positioning methods cannot work properly. Traditionally, the training phase of PRA is separately conducted for <inline-formula> <tex-math notation="LaTeX">$x$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$y$ </tex-math></inline-formula> coordinates. However, the received signal strength from access points is a unique fingerprint for each measured point, not for <inline-formula> <tex-math notation="LaTeX">$x$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$y$ </tex-math></inline-formula> coordinates separately. In this letter, we propose a method to jointly employ the <inline-formula> <tex-math notation="LaTeX">$x$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$y$ </tex-math></inline-formula> coordinates during the training phase using a novel PRA-based Gaussian process regression (GPR), named 2D-GPR. Experimental results show that the proposed 2D-GPR improves the accuracy of positioning more than <inline-formula> <tex-math notation="LaTeX">$40cm$ </tex-math></inline-formula> in limited data samples and has a lower calculation cost compared with conventional GPR.
Stability of all-trans-retinol in cream

Among the retinoids, we chose retinol (vitamin A) and studied the stability behavior of all-trans-retinol in creams. We observed thermal isomerization from all-trans-retinol to 13-cis-retinol, and this isomerization was a function of increasing temperature and oil content in creams. In addition, when the possibility of contact between retinol and water in creams was enhanced, retinol could be easily dehydrated to anhydro-vitamin A. Therefore, a balance of oils and water is considered to be important for the stabilizing of retinol in cream. We found that the reduction of all-trans-retinol in cream was caused by compound factors : thermal isomerization by temperature, dehydration by water, decomposition by oxygen, and peroxide in the surfactants or oils used in creams.
A facile colorimetric assay for determination of salicylic acid in tobacco leaves using titanium dioxide nanoparticles

A facile, colorimetric method for salicylic acid (SA) detection in tobacco leaves was developed using titanium dioxide nanoparticles (TiO2 NPs). The sensing strategy is based on the reaction of TiO2 NPs with SA at pH 5.5, which results in an intramolecular ligand to metal charge transfer transition between salicylate and Ti(IV) on the surface of TiO2 NPs, and causes the TiO2 NP solution to turn yellow. The TiO2 NP probe exhibits high selectivity for SA over seven structural chemicals (4-hydroxybenzoic acid, 3-hydroxybenzoic acid, benzoic acid, acetylsalicylic acid, phenol, methyl salicylate, and jasmonic acid). Moreover, the difference in the absorbance of the TiO2 NP solution is proportional to the concentration of SA over the range from 0.02 to 1.0 mM (R2 = 0.992). By using the TiO2 NP probe in 5 mM sodium acetate (pH 5.5) solutions, the limit of detection for SA was 15.4 μM at a signal-to-noise (S/N) ratio of 3. Furthermore, the practicality of the TiO2 NP probe was validated for the determination of SA in tobacco leaves by demonstrating its advantages including simplicity and selectivity.
Formation of Zinc–Antimony‐Based Spinel Phases

Formation of spinel phases in ZnO–Sb2O3and ZnO–Sb2O3–Bi2O3systems is studied by the use of X-ray diffraction. The formation of nonstoichiometric Zn2.33Sb0. 67O4phase is observed in both the systems at ∼900°C. However, in these systems, at higher temperatures (T≥ 1100°C), formation of the inverse spinel phase Zn7Sb2O12is observed. The study has been extended to understand the effect of CrO3doping on the stability of the different spinel phases in the previously mentioned systems. Interestingly, in both the systems, samples doped with CrO3, displayed the presence of Zn2.33Sb0. 67O4phase <1200°C, indicating the stabilization of the spinel phase by CrO3.
Adsorption of basic dye onto raw and surface‐modified agricultural waste

The application of raw Bangalora (Totapuri) mango seed kernel powder (RMS) and surface‐modified Bangalora (Totapuri) mango seed kernel powder (SMMS) for the removal of methylene blue (MB) dye from aqueous solution was investigated under ambient conditions. The adsorbent was characterized by the FTIR and SEM analyses. Batch adsorption studies were conducted by varying the solution pH, adsorbent dose, initial MB dye concentration, and contact time. The optimum conditions for the adsorption of MB dye onto the adsorbent was found to be: pH (8.0), adsorbent dose (1.0 g: RMS and 0.4 g: SMMS), contact time (60 min: RMS and 30 min: SMMS), temperature of 30°C for an initial MB dye concentration of 100 mg/L. Adsorption isotherm data were analyzed by the Langmuir, Freundlich, Temkin, and Dubinin‐Radushkevich isotherm models. Experimental data was successfully applied to the Freundlich model than the Langmuir model, and the maximum monolayer adsorption capacity was found to be greater for SMMS than the RMS. Adsorption kinetics was tested with the pseudo‐first‐order and pseudo‐second‐order kinetic models. The kinetic results show that the adsorption process followed the pseudo‐second‐order kinetic model. Adsorption kinetic data were further applied to the intraparticle diffusion, Boyd kinetic and shrinking core models to explain the adsorption mechanism. Adsorption mechanism results shows that the adsorption process was controlled by both internal and external diffusion. The results of this study show that the SMMS could be used as an effective and low‐cost adsorbent for the removal of dyes from aqueous solution. © 2013 American Institute of Chemical Engineers Environ Prog, 33: 87–98, 2014
Studies on electro‐conductive yarns prepared by in situ chemical and electrochemical polymerization of pyrrole

This work deals with preparation, characterization, and performance of electro-conductive yarns prepared by in situ chemical and electrochemical polymerization of pyrrole. Box-Behnken design in conjunction with response surface analysis has been used to study the electrochemical polymerization process. The effect of electrochemical process parameters on the electrical resistivity has been reported. Further, the electrical and electromechanical behaviour of the electro-conductive yarns thus produced has also been reported. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Non‐Newtonian flow in porous media

This paper describes a preliminary study of the linear flow of a non-Newtonian fluid, a water solution of Dextra (a polysaccharide), in porous media. A modification of Darcy's law, which uses capillary rheology data, is developed to describe non-Newtonian flow in underground reservoirs. The generalization, in effect, replaces the porous media with a capillary of equivalent radius proportional to the square root of the ratio of permeability to porosity. The constant of proportionality αo should be independent of permeability and porosity for a given type of rock. This has been partially confirmed experimentally. In principle, a capillary rheogram and a single core test permit evaluation of αo. Then non-Newtonian flow can be predicted in this type of rock regardless of porosity, permeability, or flow rate.
The difference in the intermolecular forces of H2O and D2O

The lattice energy of a compound at O deg K can be obtained from the heat of sublimation at O deg K, the zero-point energies due to the various intermolecular vibrations, and the difference between the crystal and the gas in the intramolecular zero-point energies. The difference in the lattice energies of isotopic molecules which have the same crystal structure is a good measure of the difference in their intermolecular forces. The lattice energy of H/sub 2/O and the difference in lattice energies of H/sub 2/O and D/sub 2/O have been calculated from calorimetric and spectroscopic data. The lattice energy of D/sub 2/O at 0 deg K is higher than that of H/sib 2/O by 1.27 plus or minus 0.6 kJ mole/sup -1/. The difference is presumably due to the different intermolecular forces consequent on the anharmonic zero-point intramolecular vibrations, and the difference of dipole moments is probably the major contribution. This is the first clear evidence that isotopic molecules may have appreciably different intermolecular forces. Tbe lattice energy of ice at 0 deg K is higher than is usually assumed because of the difference of zero-point energies between the solid and the vapor and it amounts to 56.0 xmore » 0.7 kJ mole/sup -1/. Most of the assigned error is caused by the uncertainties in the distribution of intermolecular rotational frequencies. (auth)« less
Influencia de apropiación de valores para la convivencia de niños dentro del aula de clases de la Escuela Normal Superior Federico LLeras, de Puerto carreño, Vichada

A traves de este estudio se busco desarrollar acciones pedagogicas para la apropiacion en valores para la convivencia en el aula de clases del grado 4to de Educacion Basica de la Escuela Normal Superior Federico Lleras de Puerto Carreno, Vichada, una institucion que posee fortalezas en muchos aspectos, sin embargo en la seccion mencionada se han presentado algunos actos de violencia verbal y fisica entre los estudiantes por lo cual fue necesario efectuar este estudio con la finalidad de aportar estrategias que minimicen la problematica, es por ello que se consideraron los valores para favorecer la convivencia en el aula, en busqueda de cincelar un ciudadano de bien capaz de desenvolverse en la sociedad. Cabe senalar que el estudio se sustento en la teoria critica especificamente en la investigacion accion que aporte soluciones a los problemas que se presentan en el contexto escolar. Por consiguiente, la poblacion estuvo conformada por veintinueve (29) estudiantes de 4to grado a quienes se les aplico una encuesta contentiva de ocho (8) preguntas referentes a la tematica a fin de constatar los conocimientos y experiencias en esta area. Asimismo, es significativo mencionar que la intervencion se disenaron dos (2) talleres dispuestos a dar aportes significativos en los estudiantes en la apropiacion de valores para la convivencia que es la capacidad de las personas de vivir con otras (con-vivir) en un marco de respeto mutuo y solidaridad reciproca; implica el reconocimiento y respeto por la diversidad, la capacidad de las personas de entenderse, de valorar y aceptar las diferencias; los puntos de vista de otro y de otros.
Highly active Si-MCM-41-supported Ga2O3 and In2O3 catalysts for friedel-crafts-type benzylation and acylation reactions in the presence or absence of moisture

Ga 2 O 3 and In 2 O 3 (which are amphoteric and basic in nature, respectively) supported on mesoporous Si-MCM-41, or even on micro- or macroporous inert catalyst carriers, are highly active and reusable catalysts for the benzylation of benzene and acylation of aromatic compounds, even in the presence of moisture. Moisture has a beneficial effect, more particularly for the acylation reaction. It causes an increase in the reaction rates for both the reactions and also a large increase in the induction period for the benzylation reaction but not for the acylation. The induction period is due to the presence of moisture adsorbed on the catalyst, which is to be replaced by the reactant(s) to start the catalytic reaction.
Preparation of magnetic mesoporous core–shell nanocomposites for cinnamic acid hydrogenation

A novel magnetic mesoporous core–shell nanocomposite Fe3O4@nSiO2@mSiO2@Ni–Co–B was prepared by the combination of a modified Stober sol–gel process, a surfactant-templating method and self-assembly. It has a multi-shell structure with ferroferric oxide as core, dense nonporous silica and mesoporous silica as middle layers in sequence and an Ni–Co–B amorphous alloy as outer layer, as confirmed by transmission electron microscopy and nitrogen adsorption–desorption. This nanocomposite showed high activity and good selectivity in the selective hydrogenation of cinnamic acid to hydrocinnamic acid. Notably, it can be easily separated by a magnet after reaction due to its high magnetism and recycled effectively five times.
Antitumor Efficacy of Taxane Liposomes on a Human Ovarian Tumor Xenograft in Nude Mice

Taxanes such as paclitaxel (Taxol) and docetaxel (Taxotere) are promising agents for use against ovarian cancer and other malignancies. Recently, SB-T-1011, a semisynthetic taxane, has been prepared from 14-hydroxy-10-deacetylbaccatin III. SB-T-1011 shows similar or greater in vitro cytostatic activity than paclitaxel, depending on the tumor cell line. The administration of taxanes is problematic due to their low solubility in most pharmaceutically acceptable solvents; formulations used clinically contain Cremophor/ethanol (diluent 12) or polysorbate 80/ethanol, excipients which may cause serious adverse effects. To eliminate these vehicles, we have prepared paclitaxel liposome formulations. The objective of the present work was to evaluate the antitumor activity of paclitaxel and two semisynthetic analogs in Cremophor-based and liposomal formulations. Antitumor activity was evaluated against A121a, a taxane-sensitive human ovarian tumor, growing as subcutaneous xenografts in athymic nude mice. Free and liposomal formulations of each taxane showed similar antitumor effect. The antitumor activity of paclitaxel and SB-T-1011 was similar, and docetaxel was more potent than either paclitaxel or SB-T-1011. Overall, taxane liposomes were better tolerated and more easily administered iv than taxane formulated in Cremophor/ethanol.
Parâmetros genéticos para produções de leite e gordura nas três primeiras lactações de vacas Holandesas

In this study 9,527 lactations of purebreed Holstein cows, calved between 1988 to 1997, from herds in the Minas Gerais State, were analysed. Two data sets were established: one with first lactations only and another with the first lactation until the third one. Milk and fat 305-day yields were analysed using a multivariate mixed model and restricted maximum likelihood procedure (REML). The milk and fat 305 days yields averages were respectively 5,870 ± 1,662 kg and 199 ± 55 kg for set I and 5,521 ± 1,523 kg and 187 ± 50 kg for set II in the first lactation, and 6,421 ± 1,789 kg and 215 ± 58 kg for the second lactation, and 7,045 ± 1,903 kg and 231 ± 60 kg for the third lactation, respectively. Heritabilities estimated for milk and fat yields in set I (first lactation) were . 28 ± . 04 and . 20 ± . 03 and using the set II, were . 16 ± . 09 e . 9 ± . 9 for milk and fat yields in the first lactation, . 17 ± . 11 and . 20 ± . 11 for second one, and . 16 ± . 10 and . 10 ± . 16 in third lactation, respectively. Genetic correlations were high and ranged from . 86 to 1.0.
Cloning and expression of human recombinant isoform a of glycine–N–acyltransferase

Awareness of detoxification, nowadays known as biotransformation, has become an integral part of our daily lives. It is a modern buzz word that is used to promote anything from health food to enhancement of performance in sports. Another lesser known application for detoxification is as a therapy for alleviating symptoms of inborn errors of metabolism. Detoxification is the process where endogenous and xenobiotic metabolites are transformed to less harmful products, in the liver and kidneys, in two phases. Phase 1 detoxification includes oxidation, hydroxylation, dehydrogenation metabolic reduction and hydrolysis. Phase 2 detoxification uses conjugation reactions to increase hydrophillicty of metabolites for excretion in bile and urine. Glycine N-acyltransferse (GLYAT; EC 2.3.1.13) is one of the amino acid conjugation enzymes. There are two variants of human GLYAT. I focused on the full-length mRNA human GLYAT isoform a, with a long term view of using it as a viable therapeutic enzyme for enhanced detoxification of harmful metabolites. I investigated if it is possible to clone and express a biologically active GLYAT. To achieve this goal I used three expression systems: traditional bacterial expression using the pET system; second generation cold shock bacterial expression using the pCOLDTF expression vector to improve solubility of the recombinant protein; and baculovirus expression in insect cells since therein some form of post translation glycosylation of the recombinant protein can occur which might improve solubility and ensure biological activity. The recombinant GLYAT expressed well in all three expression systems but was aggregated and no enzyme activity could be detected. A denature and renature system was also used to collect aggregated recombinant GLYAT and used to try to refold the recombinant protein in appropriate refolding buffers to improve solubility and obtain biological activity. The solubility of the recombinant GLYAT was improved but it remained biologically inactive.
Infrared characterization of amorphous and polycrystalline D2O ice on controlled wettability self-assembled alkanethiolate monolayers

Infrared reflection–absorption spectroscopy has been used to characterize thin overlayers (1–200 A) of D2O ice deposited in UHV onto a set of self-assembled alkanethiolate monolayers (SAMs) of controlled wettabilities on gold. The SAMs were prepared from a series of controlled composition, mixed solutions of HS(CH2)15CH3 and HS(CH2)16OH, making it possible to investigate the whole wettability range from θ≈0° to θ=112°, where θ is the static contact angle with water. Dosing of D2O and infrared measurements were carried out at selected sample temperatures between 82 and 150 K. Experimental spectra of ice overlayers recorded below 100 K on all SAM substrates are in good agreement with simulated reflection–absorption spectra, derived from the optical constants of amorphous ice. This agreement allows accurate film thickness determination. In contrast, lack of correspondence in spectral signature is noted between the spectra of annealed films and simulated polycrystalline (or amorphous) ice spectra. We interpre.