N-Hexane Isomerization on Ni-Pt/Catalysts Supported on Mordenite

The aim of this work was to evaluate the catalytic properties for n-hexane isomerization of bifunctional monometallic (Ni or Pt) and bimetallic catalysts (Pt-Ni), using HMOR zeolite as support. The method used for metal dispersion in the zeolite was competitive ion exchange using ammine complexes [Ni(NH3)6]Cl2 and [Pt(NH3)4]Cl2 as precursors. The catalysts were characterized by X-Ray diffraction, X-Ray energy dispersion spectroscopy, temperature-programmed reduction and transmission electron microscopy. The n-hexane isomerization reaction using the catalysts was carried out to evaluate the catalyst activity. The reaction was carried out in a fixed bed reactor operating at 250?C, 1 atm, H2/C6 = 9 molar ratio. The profiles obtained from TPR suggest that, for bimetallic catalysts, the presence of platinum facilitates the reduction of Ni2+ cations. The bimetallic catalysts presented a higher activity in the isomerization of n-hexane when compared to the monometallic ones, as well better stability as the Pt content in the solid increases.

Sol–gel La2O3–ZrO2 mixed oxide catalysts for biodiesel production

Different La2O3 contents（0, 1, 2, 3, and 5 wt%） were used to prepared La2O3-ZrO2 mixed oxides calcined at 600 ℃ by the sol-gel method. The catalytic activity was measured as biodiesel production from canola oil through a transesterification reaction. The characterization results indicate that the La2O3 monolayer formation and extent of basicity of m-ZrO2 have a large influence on biodiesel production.Greater biodiesel conversion（56% at 4 h） was obtained with the 3% La2O3-ZrO2 catalyst in the presence of basic sites and the formation of a monolayer of La2O3. The decrease in the catalytic activity for 5% La2O3-ZrO2 resulted from the loss of active sites on the catalyst because of agglomeration, which was suggested by XPS and the isoelectric point. The kinetic data fit to a pseudo-first order constant, and the largest kinetic constant corresponds to 3% La2O3-ZrO2, currently the largest heterogeneous non-alkaline metal catalyst reported for a transesterification reaction.

Shear Rate Effect on the Viscosity of Homemade and Commercial Tomato Sauce

Rheological characterization of tomato products is important not only for design of unit operations, but also to optimizeprocesses and guarantee high quality of food products. Time dependence is related with structural changes due to shear rate. Thus,rheological characterization as a function of time is extremely important to understand the changes that occurred in food productsduring commercial processes. However, these characterizations are rare in the literature for tomato products. Those rheologicalproperties depend of several parameters, such as agronomic, structural and process parameters. In this study, the effect of shear rateon the viscosity at room temperature （22 ~C） of two kinds of tomato sauce （homemade and commercial） is analyzed; using aBrookfield viscometer model 4535, Lab-Line Instruments. Homemade sauce was prepared with fresh saladette tomatoes from a localmarket. Rheological analysis was performed at shear rates from 0.05 to 10.47 sl; using all the spindles available. Statistical analysiswas made using LSD and Duncan tests with a confidence interval of 95% （p-value of 0.05）. It was demonstrated that homemade andcommercial tomato sauce behaved as a thixotropic fluid, due to the typical decrease on viscosity samples observed when testing timewas increased. When tomato sauce is at rest, it has a gelled tridimensional structure; and, as soon as a shear stress is applied, themovement generates an alignment of tomato constituent chains in flow direction, breaking physic entanglements and thus causing adecrease in viscosity as a function of time. Furthermore, it was discovered that the viscosity of homemade sauce was higher than theviscosity of commercial sauce. The latter may be due to the pre-thermal treatment. During this unit operation, polymeric chains oflycopene most likely break into smaller chains of isoprene, causing the observed decrease in viscosity. Besides, commercial saucecontains additives, seasonings, preservatives and thickeners that are not in a homemade sauce.

Motor Effects of 1,3-Disubstituted 8-Styrylxanthines as A_(1) and A_(2) Adenosine-Receptor Antagonists in Rats

A series of 1,3-substituted 8-styrylxanthines (11a-d) was synthesized, under chemo- and regioselective conditions, in a good overall yield. The compounds showed affinity towards both A1 and A2A-adenosine receptors by radioligand binding by means of in vitro assays. The (E)-3-ethyl-1-propyl-8-styrylxanthine (11a) showed the greatest affinity towards the A2A receptor, whereas (E)-3-pentyl-1-propyl-8-styrylxanthine (11d) showed the greatest affinity for the A1 receptor. When the 8-styrylxanthines 11a (A15Et) and 11c (A15Bu) were administrated in rats, which were previously injured with 6-hydroxydopamine at the substantia nigra pars compacta (SNc), the turning behavior decreased 50%. Based on these results we propose to A15Et as a potential compound to treat some symptoms of Parkinson’s disease.

Optimization of Analytical Conditions to Determine Steroids and Pharmaceuticals Drugs in Water Samples Using Solid Phase-Extraction and HPLC

Two reliable methods were optimized to determine two steroids (17?-Estradiol and 17?-Ethinylestradiol) and two pharmaceutical drugs (ibuprofen and naproxen) using Solid-Phase Extraction (SPE) for sample preparation and High Performance Liquid Chromatography (HPLC) for analysis. SPE (C18) conditions were evaluated varying elution solvent volume, pH conditions and sample mass in the cartridge and reduction techniques of the extract. The efficiency of the analytical methods was evaluated by spiking ultrapure water samples with compounds at three and four levels of concentration for steroids and pharmaceutical drugs, re- spectively. The recoveries were independent (P > 0.05) of added mass of target analytes with a repeatability lower than 6.5% for steroids and 12.1% for pharmaceutical compounds. The recovery factor (coefficient of variation, CV) was higher than 83% for steroids (CV 93% for pharmaceuticals (CV < 5.2%). The optimized analytical method was applied for the evaluation of a steroid degradation test using ozone, finding that the estimated limit of detection is sufficient to determine the residual mass (μg?L–1) of 17β-Estradiol after the experiment.

Simulaccion Processes of a Mathematical Model to Determine the Growth of Tomato under Plastic Cover

The tomato is one of the horticultural crops of the greatest economic value;for this reason, flexibility of management is usable. The population density in a crop of vegetables is determined by the distance between the plants and so it is necessary to choose the number of plants per square meter since the saturation of plants will lead to competition between sunlight, nutrients and weed. The objective of this work is to make the appropriate investigation for the use of the model proposed in order to describe the growth of tomato in greenhouse to high density of two plants per container to two bunches per plant, resulting in eight plants per square meter to grow, by means of a simulator of growth by computer. Of this work, it is concluded that it is possible to use the model to describe the growth of plants, and in the near future it will be possible to develop a simulator by computer of the growth of these crops in order to improve their quality and increase their production.

Correspondence amongst the PENO Test Battery Cognitive Results and Hippocampal Lesions in Alzheimer’s Disease

Alzheimer’s disease (AD) is characterized by a decline of cognitive functions. Distinctive histopathological hallmarks are neuritic plaques, neurofibrillary tangles, and synaptic alterations. Abnormally enlarged synaptic structures called “Meganeurite clusters” have been linked to plasticity changes. The aims of this study were to determine if cognitive impairment was related to specific neuritic and synaptic degeneration processes in patients with AD, and if the results of a cognitive test could be correlated with the histopathological damage. The neuropsychological evaluation obtained by the Protocole d’evaluation neuropsychologique optimal (PENO) test battery was used in live AD and control individuals. The histopathological evaluation of their brain after their death was carried out with specific polyclonal and monoclonal antibodies to Aβ, pTau protein, synaptophysin, and GAP-43. Images were obtained by confocal microscopy. The results showed a significant difference between healthy controls and Alzheimer’s patients in neuropsychological evaluation and histopathological hallmarks expression. The most significant positive correlation in AD patients was between memory and language results with the PENO test and the presence of Aβ +pTau+ plaques in the hippocampus. An interesting negative correlation was between cognitive impairment and the presence of Meganeuritic clusters, considered as “plasticity” markers. These results strongly supported the use of the PENO battery test to evaluate the progression of cognitive impairment in AD prone individuals and patients due to the strong correlation of the test results with histopathological brain lesions characteristic of Alzheimer’s disease.

Corrosion Inhibition of Carbon Steel in Acidic Mediaby Using Actinidia deliciosa(Kiwifruit)Extract

The corrosion inhibition of 1018 carbon steel in 0.5 M H2SO4 by using Actinidia deliciosa (Kiwifruit) peel extract has been investigated by using potentiodynamic polarization curves and electro-chemical impedance spectroscopy. Two kinds of extracts are investigated, one from the tender, and another one from ripe Actinidia deliciosa. Concentrations include 0, 25, 50, 75, and 100 ppm at room temperature. Results indicate that both kind of extracts acted as good corrosion inhibitors, is more efficient in the ripe extract. Corrosion inhibition efficiency increases with increasing its concentration for ripe extract, whereas for the tender Actinidia deliciosa, the higest inhibitor efficiency is obtained by adding 25 ppm and decresaing with a further increase in its concentration. Both extracts improve the passive film properties by decreasing the passive current density values. It is found that the corrosion inhibition is due to the presence of heteroatoms present in Actinidia deliciosa, mainly quercitine, which is physically adsorbed in the steel following a Frumkin type of adsorption isotherm which forms a protective film.

Oxidation and Coatings for Power Generation： New Super Ultra Critical Steam Turbines

The steels with chromium contents between 9%and 12%wt are used for power plants with advanced steam oxidation conditions.They present good creep properties as 9%Cr steels and good oxidation resistance,at the temperatures range between 500℃～600℃.In the last years numerous investigation in development of coatings has been realized with the aim the protected them against the oxidation in order to allow operation of steam turbines at 650℃.In this study,Al-Hf protective coatings were deposited by CVD-FBR on ferritic steel HCM-12A followed by a diffusion heat treatment,have shown to be protective at 650℃under steam for at least 3000 hours of laboratory steam exposure under atmospheric pressure.Morphology and composition of coatings were characterized by different techniques, such as scanning electron microscopy(SEM),electron probe microanalysis,and X-ray diffraction(XRD). On the other hand,volatile species by mass spectrometry(MS) and thermogravimetric measurements (TG) during the initial stages oxidation of the P92 ferritic steel without and of Al and Al/Si coating by chemical vapour deposition in fluidized bed reactors(CVD-FBR) at 650℃in Ar+20%H_2O for 150 h were studied.In order to go forward to coatings design the Thermocalc code is used as base for the MSdata. TG-MS experiments were conducted in a closed steam loop in order to obtain information about the oxyhydroxides formation as reaction between coatings and steam.From those results the role of the different coating element could be established and optimized for the coating durability.An oxidation mechanism based on the TG-MS results is given.The morphology/composition and structure of the oxidized samples were also studied using SEM/EDS and XRD techniques.

Temperature Effect on the Viscosity of Commercial Carrot Puree

Temperature effect was evaluated over the viscosity of commercial carrot puree in the range 30 to 60 ℃, using aBrookfield viscometer, model 4535, Lab-Line instruments. In order to perform the viscosity tests, 28 specimens of carrot puree froma local market were used. Totally, 72 tests （each one with a couple replicas） were performed during five minutes, using fourtemperatures （30, 40, 50 and 60 ℃）, six shear rates （0.26, 0.52, 1.05, 2.09, 5.24 and 10.47 s1） and three spindles （4, 5 and 6）.Statistical analysis was performed using LSD and Duncan tests with a confidence interval of 95% （p value of 0.05）. In the currentstudy, it was observed that an increase in the temperature triggers a reduction in the viscosity of the carrot specimens analyzed,although the samples tested at 60℃ were deviated from this trend, which may be due to denaturation of the starch containing carrotsamples at such temperature. Multiple biochemical and micro-structural changes inside the food specimens may begin to occur belowand over the physiological range （20-45 ℃）. Experimental data were analyzed with Power Law model in order to obtain the bestfitted parameters as a function of shear rate： It was observed that the consistent index （k） decreased with an increment in thetemperature; while all the values of parameter ＂n＂ lesser than one, which means that the puree samples behaved as a pseudo-plasticfluid. Besides that, an Arrhenius model was used to fit the parameters as a function of temperature： Parameter A was lower usingtheexperimental data at shear rates of 10.47 s-1. The modeling performed may be helpful for the appropriate selection of some processvariables, as the shear rate and operation temperature, used for the production of carrot puree; all this is in order to obtain the finishedproduct with the desired consistency.

PbS：Hg2＋ Nanostructures Films by Chemical Bath

The growth of nanocrystalline PbS films by chemical bath deposition （CBD） onto glass at temperatureT = 40 ± 2℃, is presented in this research. We report on the modification of structural, optical nanostructures due to in situ Hg-doping.The morphological changes of the layers were analyzed using AFM. XRD spectra displayed peaks at 20 = （26.00, 30.07, 43.10, 51.00, 53.48）, indicating growth on the zinc blende face. The grain size determined by x-rays diffraction of the undoped samples, was found -36 nm, whereas with the doped sample was 32-23 nm. Optical absorption, transition direct and indirect the forbidden band gap energy （Eg） shifts discloses a shift in the range 1.45-2.4 eV.

Substituent Effect of Chiraldiphenyl Salen Metal （M = Fe（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Zn（Ⅱ）） Complexes for New Conceptual DSSC Dyes

The authors have designed and synthesized new chiral salen-type metal （M = Fe, Co, Ni, Cu, Zn） complexes （1-5） for new conceptual dyes （co-sensitizer or colorful multi-dyes） of DSSCs （dye-sensitized solar cells）. The authors measured substituent effects on their absorption spectra and redox properties, and compared them with TD-DFT （time-dependent density functional theory） calculations. Electron withdrawing groups resulted in red-shift of ultraviolet-visible （UV-Vis） spectra. For the first time, the authors also proposed and confirmed the importance of substituent effects on their electric transition dipole moments, calculated by TD-DFT for designing dyes. Chemisorption for TiO2 of the complex by carboxyl groups was confirmed by XPS measurement. In view of electronic properties, all compounds have the possibility to be dyes of DSSCs.

Ab Initio Study of Aluminum-Phosphorus Co-doped Graphene

In the present work it is studied the phosphorus-aluminum co-doping effect on the electronic and structural graphene properties using ab initio calculations in the framework of DFT （density functional theory）. The doping of graphene with substituent heteroatoms can modify the band structures as well as the electron transfer, improving the electronic performance that could enhance the sensing ability in gas sensor devices. The incorporation of heteroatoms in the graphene monolayer alters the unit cell. The alteration degree depends on the dopant concentration. Furthermore, the electronic properties were modified by opening the gap up to 0.61 eV produced by the combination of phosphorus and aluminum as dopants. The dopant concentration can be controlled, which causes different degrees of semiconductor behavior on the co-doped graphene.

Screening chloroplast regions in Calophyllum brasiliense (Calophyllaceae) for suitability for population genetic analyses

The uniparental inheritance and conserved structure of the chloroplast genome among many angiosperms makes it suitable for constructing gene lineages and inferring population histories based on these relationships. However, the analysis of a single chloroplast region to solve population issues has not yielded the desired amount of variability due to the low mutation rate. Therefore, it is necessary to screen and carefully analyze chloroplast intergenic or intronic regions to select the most appropriate for studying the genetic variability in the chloroplast genome of a particular taxon. In this context, the aim of this work was to characterize 8 regions in Calophyllum brasiliense using 11 selected primer pairs and to evaluate their usefulness for phylogeographic analysis. Intergenic spacers petA-psbJ, petG-trnP and rp132-trnL and the trnL intron demonstrated potentially informative sites. The combination of these 4 regions will allow the analysis of genetic population structure and the integration of historical aspects to inform strategies for conserving C. brasiliense, especially for highly impacted populations and those at risk of local extinction.