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In this paper we explored several issues surrounding metal-free selective synthesis of dibenzo[g,p]chrysene (DBC) by steps that consist of the dimerization of fluorenones and the carbocation 1,2-shift. We focus on structurally non-symmetric two fluorenones having a bromine atom as a reactive moiety and a tert-butyl group as a solubilizing agent: One is 4-bromo-2,7-di-tert-butyl-9-fluorenone (1), and the other 4,7-dibromo-2-(tert-butyl)-9-fluorenone (2). Each starting 1 and 2 undertakes the homo-coupling to give two isomeric spiroketones and the following Wagner-Meerwein rearrangement to yield two isomeric DBCs. The spiroketone intermediates have now been crystallographically characterized, which informed us of the exact structures and lead us to comprehend which aryl group predominantly migrates from one carbon to a neighboring carbon along with production of DBC skeletons. Although the construction of DBCs proved to be involved in four paths, it seems likely now that a clear demonstration of making different DBCs by different reaction conditions enables us to accomplish selective synthesis of DBCs.

En el presente estudio se identifican factores de la innovación que han tenido un impacto en el desarrollo del sector fotovoltaico. Considerando una muestra de 15 países entre 1992 y 2011, se encontró que la aplicación de los instrumentos de política pública, como: tarifa de retroalimentación, los subsidios directos al capital y los fondos de inversión, promueven la innovación en este sector. Además, la variación de precios de los módulos fotovoltaicos muestra una correlación inversa con el número de patentes internacionales, el efecto mayor se obtiene con un periodo de rezago de dos años. La cantidad de reservas de petróleo y las exportaciones de energía eléctrica con un rezago de dos años también favorecen la innovación en el sector fotovoltaico.

The provision of an appropriate shelter was the basic premise of human habitats from remote times, aimed at providing indoor comfort conditions and protection from the external environmental conditions. The role the building envelope plays is essential to achieve this objective. This work investigated the thermal performance of three different experimental modules (EM) with a solar control system (SCS) and different envelope characteristics relative to a control module (CM). The results showed that the EM with the SCS and the rammed earth walls presented the best thermal performance relative to the CM. It is expected that the results can be applied in low cost housing of various regions of the country for providing thermal comfort conditions of the occupants and to reduce the electricity consumption for the use of air conditioning systems (HVAC), and eventually, to diminish the burning and emission of greenhouse gases (GHG) to the environment.

The growing demand for food and the unstable price of fossil fuels has led to the search for environmentally friendly sources of energy. Energy is one of the largest overhead costs in the production of greenhouse crops for favorable climate control. The use of wind–solar renewable energy system for the control of greenhouse environments reduces fuel consumption and so enhances the sustainability of greenhouse production. This review describes the impact of solar–wind renewable energy systems in agricultural greenhouses.

To generate bright water-window (WW) soft x rays (2.3–4.4 nm), gold slab targets were irradiated with laser pulses (1064 nm, 7 ns, 1 J). Emission spectroscopy showed that the introduction of low-pressure nitrogen enhanced the soft x-ray yield emitted from the laser-produced Au plasma. The intensity of the WW x-ray transported in a 400-Pa N2 atmosphere from the laser-produced plasma increased by 3.8 times over that in vacuum. Considering a strong x-ray absorption, the x-ray yield emitted directly from the Au plasma in the N2 gas was evaluated to be 13 times higher than that in vacuum. Although similar measurements were made for various gases, only N2 gas causes an increase in a soft x-ray yield. The processes leading to this enhancement mechanism were revealed by using hydrodynamic simulation and atomic structure codes.

In recent years, silicon-related photoluminescent materials have attracted great attention due to their optical properties. This work aims to study the deposited silicon oxycarbide (SiOxCy) thin films by using the Organic Catalytic Chemical Vapor Deposition (O-Cat CVD) technique. Monomethyl Silane gas [MMS; (CH3-SiH3)] was used as an organometallic silicon precursor, and tantalum (Ta) filament was used as a catalyst. The influence of deposition time on the photoluminescent properties, resulting from the Si/C ratio in thin layers, was assessed. The nature of shifted silicon-oxygen stretching bonds from their stoichiometry value was discussed by Fourier Transform Infrared (FTIR) analysis. The chemical composition of the SiOxCy matrix was confirmed by X-ray Photoelectron Spectroscopy (XPS) analysis. Wide and intense photoluminescence (PL) emissions were observed for as-deposited films at substrate temperatures as low as 200 °C and the origin of emissions was explained by different defect mechanisms. Moreover, the shift of PL spectra from the red to the blue band was also explained. This investigation provides further understanding of the SiOxCy thin film properties to improve its optical properties and produce it more safely.

Regio-defined syntheses of tetra-brominated dibenzo[g,p]chrysene (DBC) derivatives are described, with a description of different patterns of the four-bromine-positions. These derivatives were designed with two features: one is installation of butyl groups for being processable in solution-phase, and the other is attachment of bromine atoms for being variable. Thus, these brominated devices would enable us to achieve diversity-oriented preparation of solution-processable DBC derivatives.

This work presents a simple and low-temperature method to prepare a variety of Lead selenide (PbSe) nanostructures, using aqueous solutions of Pb(NO3)2 and NaHSe. Nanostructures with different morphology were obtained by varying the Pb:Se molar ratio, as well as the mixing sequence of NH4OH with either Pb(NO3)2 or NaHSe. Nanoparticles with different shapes (spherical and octahedral), and self-assembled structures (flakes and ribbons) were observed by Transmission Electron Microscopy. X-ray results confirmed that the PbSe rock-salt crystalline structure was obtained for all of the prepared samples. The crystal size is in the order of 7.3 to 8.9 nm for single nanocrystals. The absorption spectra of the samples show exciton absorption bands at 1395 nm and 1660 nm. This material could be used to develop more advanced structures for thermoelectric generators.

In this work, we reported a chemical approach to prepare aluminium and indium co-doped ZnO thin films (AIZO) by ultrasonic spray pyrolysis. Film depositions were carried out on soda lime glass substrates at 425 °C by using a spray solution containing zinc acetate as zinc precursor, aluminium acetylacetonate as Al dopant source and indium (III) acetate as In dopant source. Physical properties such as structural, morphological, optical and electrical properties were studied with respect to the equal variations in co-dopants concentration (0.5–3 at%). X-ray diffraction patterns proved that films are poly crystalline with (002) preferential orientation. Scanning electron microscopy analysis showed that AIZO films grown like hexagonal nanopyramids, elongated grains and irregular trigonals. Optical transmittance ~85% and a minimum resistivity of 1.3×10−3 Ω cm, are achieved for films when co-doped with 1.5 at% of Al and 1.5 at% of In, confirm that AIZO films are suitable for transparent conductive oxide (TCO) applications.

This article analyzes the determinants of annual installed capacity of photovoltaic power (PV) at a country level. Our results suggest that in the 15 countries studied, the factors promoting the deployment of PV systems are the net consumption of renewable electricity, the existence of a feed-in tariff and sustainable building requirements, as well as the quantity of scientific publications. Meanwhile, the variables that negatively impact the PV deployment are oil reserves and the carbon dioxide emissions from energy consumption. Based on data from 1992 to 2011, the analysis shows that the deployment of PV requires long-term support for scientific research. One successful policy for PV deployment has been the feed-in tariff. Sustainable building requirements also significantly support PV deployment. The deployment of PV is one step towards a low-carbon energy system but the emergence of any renewable energy technology must cope with the energy sector’s domination by fossil fuels interests.

Resumen91% de la energía que se consume en el mundo se suministra por hidrocarburos, los cuales también son una de las principales fuentes de ingreso económico de algunos países de Latinoamérica, incluyendo México. El problema de la dependencia hacia los hidrocarburos se puede agravar con el incremento en la demanda de energía debido al constante crecimiento de la población. Es por ello que las nuevas políticas en energía se orientan a diversificar las fuentes de energía, principalmente, al uso de las energías renovables. Una posible solución es el uso del hidrógeno como energético, que se puede obtener a partir de recursos renovables como la biomasa para generar energía limpia en pequeñas ciudades. Se ha demostrado que algunos grupos de bacterias fermentadoras, tienen la capacidad de generar hidrógeno a partir de azúcares simples. Se realizó un estudio cromatográfico para determinar la presencia de biogás en los gases producidos por la fermentación natural de la bebida mediante algunas bacterias. En adición, mediante imágenes de microscopia se caracterizaron las bacterias implicadas en los procesos fermentativos. Las muestras se tomaron del pulque, bebida alcohólica natural de origen prehispánico. Con estos estudios se demostró la factibilidad para el uso de este biogás para obtener energía e hidrógeno sin alterar las condiciones naturales de fermentación de la bebida.Abstract91% of the energy consumed worldwide is supplied by hydrocarbons, which are also a major source of income for some of the Latin American countries, including Mexico. The problem is aggravated with the increase in the demand of energy due to the steady population growth. For this reason, the new energy policies are moving towards diversifying sources of energy, in particular, the use of renewable energy. One possible solution, is the use of hydrogen which can be obtained from renewable sources such as biomass to generate clean energy for small towns. It has been shown that some groups of fermentative bacteria have the ability to generate hydrogen from simple sugars. A chromatographic study was performed to determine the presence of biogas in the gases produced by the natural fermentation through some of the involved bacteria, and subsequently, by microscopy to characterize the bacteria images in fermentative processes. Samples were taken from the natural alcoholic drink pulque; of prehispanic origin. These studies demonstrated the feasibility of the use of this biogas to produce energy in the form of hydrogen without altering the natural fermentation conditions of the drink itself.

Undoped zinc oxide (ZnO) thin films were reactively deposited on soda-lime glass substrates by radio frequency (rf) sputtering at room temperature. We have studied the importance of substrate rotation speed on the structural, optical and morphological properties. The rotation speeds used were 0, 20, 40, 60, and 80 rpm. The XRD measurements confirmed that films were grown with (002) plane preferential orientation. The average transmittance was above 90% in the UV–vis region. The SEM images revealed that films deposited with substrate rotation are more homogeneous than the films deposited without rotation.

This work reports the electrical and thermal transport properties of polycrystalline Bi1-xSbx (x=0.10 and 0.14) pellets in the temperature range of 20 − 300 K . The pellets were prepared by spark plasma sintering from ball-milled Bi1-xSbx powders. As semiconductor, the samples displayed n-type conductivity as indicated by the negative sign of the Seebeck coefficient. Semiconducting properties were observed for the Bi0.86Sb0.14 alloy in the entire temperature range of 20 − 300 K , whereas the Bi0.90Sb0.10 alloy exhibited metal-like behavior at low temperatures ( 20 − 120 K ) and semiconducting one at temperatures between 160 K and 300 K . The metal-like feature of the Bi0.90Sb0.10 sample was attributed to the electron conduction by means of topologically protected surface gapless states, as this material has been reported to be a 3D topological insulator. The temperature dependence of the scattering coefficient and Fermi level shift were analyzed, assuming that prepared alloys are non-degenerate semiconductors in the temperature range where their semiconducting behavior was observed. The carrier thermal conductivity was estimated from the Lorenz number and Wiedemann-Franz law. At high temperature, the thermal energy transport rate is similar for both alloys, whereas at low temperature, it depends on the characteristic electrical behavior of each sample. Interestingly, the polycrystalline nature of our samples seems not affect their electrical and thermal transport properties.

We present a systematic approach how to characterize the dynamics of a laser-produced Au plasma, generated with a commercial Joule-class laser system. By means of our diagnostic methods, we identify the dominant ionic species within the water-window spectral region, as well as the radiated energy, the x-ray emission duration and the total dimensions of the x-ray source. We present additional analysis through radiation hydrodynamic simulations to provide details about the electron temperature and density profiles and further show that the plasma exhibits nearly 20% self-absorption, while the electron temperature is limited to 400 eV. A comparison with the experimental data further allows us to verify the applied numerical code.

A straightforward route to a well-soluble dibenzo[ g , p ]chrysene (DBC) scaffold is described. The scaffold is 2,7-dibromo-10,15-dibutyl DBC, in which two butyl groups work as a solubilizing agent and two bromines play a role of changeable tags. This solution-processable DBC enabled diversity-oriented approaches for synthesis of solubilizing DBC derivatives: actually, one of the two bromines selectively undertook the first transformation, and the other bromine was subjected to the second substitution reaction. Thus, the new DBC platform provides a general entry for creation of new polycyclic aromatic hydrocarbons.

This work describes the growth of silicon&ndash, silicon carbide nanoparticles (Si&ndash, SiC) and their self-assembly into worm-like 1D hybrid nanostructures at the interface of graphene oxide/silicon wafer (GO/Si) under Ar atmosphere at 1000 &deg, C. Depending on GO film thickness, spread silicon nanoparticles apparently develop on GO layers, or GO-embedded Si&ndash, SiC nanoparticles self-assembled into some-micrometers-long worm-like nanowires. It was found that the nanoarrays show that carbon&ndash, silicon-based nanowires (CSNW) are standing on the Si wafer. It was assumed that Si nanoparticles originated from melted Si at the Si wafer surface and GO-induced nucleation. Additionally, a mechanism for the formation of CSNW is proposed.

We report the obtention of luminescent silicon oxycarbide thin films deposited by Hot-wire chemical vapor deposition technique using tetraethyl orthosilicate as precursor. Additionally, we study the effect of the chamber pressure and the post-deposition thermal annealing in oxygen and hydrogen environments on the properties of the films. All the as-deposited samples showed an intense and wide emission band centered in the blue region. The samples deposited at 0.3 and 0.5 Torr presented a high surface uniformity. The X-ray diffraction measurements did not show the presence of nanocrystalline phase, so, we attributed the emission bands to defects in the silicon oxycarbide matrix, mainly related to oxygen deficiency centers, and to hydrogen and carbon-related defects. After the thermal annealing in oxygen and hydrogen, the samples showed a significative reduction in the emission intensity because of radiative defects passivation.

Silicon thin films have been obtained with respect to the deposition time variation by using hot wire chemical vapor deposition. Silicon and related oxide particles both in crystalline phases embedded in amorphous silicon have been obtained by using tungsten as the catalyst material for the decomposition of source gases in the reaction chamber. Crystalline nature of the thin film has been shown using X-ray diffraction, transmission electron microscopy and scanning electron microcopy. X-ray diffraction patterns authenticate the presence of crystalline phases related to silicon and silicon dioxide in the matrix. Furthermore, transmission electron micrographs also revealed the presence of adjacent nature of silicon and silicon dioxide particles in the amorphous matrix. The as-deposited samples at low substrate temperature of about 200 °C have shown intense white photoluminescence spectra. No need of post-deposition annealing for light emission at room temperature has been demonstrated. This advantage of hot wire chemical vapor deposition technique could be considered for the mass production of optoelectronic devices in the future.

Aim Portopulmonary venous anastomoses (PPVA) are shunts between esophageal varices and pulmonary veins. Because PPVA can cause serious complications at the time of sclerotherapy for esophageal varices, it is essential to confirm the existence of any PPVA before treatment. Methods The study group comprised 101 patients in whom hemodynamics were evaluated on three-dimensional computed tomography (3D-CT) before either elective or prophylactic treatment of esophageal varices at Kitasato University East Hospital from October 2007 through August 2013. The presence or absence of PPVA, laboratory test results and 3D-CT findings were retrospectively examined in these patients. Results Nine patients had PPVA, and 92 patients did not. The underlying diseases in the PPVA group were: hepatitis C liver cirrhosis in three; non-B, non-C liver cirrhosis in three; non-alcoholic steatohepatitis in one; primary biliary cirrhosis in one; and autoimmune hepatitis in one. The distribution of underlying diseases did not differ between the PPVA group and the non-PPVA group. When the study variables were statistically compared between the groups, the incidence of large, coil-shaped esophageal varices (grade F3) differed significantly between the groups (P = 0.001). Multivariate analyses of factors related to PPVA revealed that only the grade F3 type of esophageal varices differed significantly between the groups (P = 0.005; hazard ratio, 5.21; 95% confidence interval, 3.1–16.4). Conclusion In patients with grade F3 esophageal varices, the treatment method should be selected on the basis of an accurate hemodynamic analysis using 3D-CT before therapy.

Oleylamine-capped tin disulfide nanoparticles were prepared by the hot-injection method using tin (II) chloride (SnCl2.5H2O) and thioacetamide as tin (II) and sulfur precursors, respectively. The as-prepared nanoparticles were rinsed with ethanol or toluene, and their structural and morphological were assessed by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy. The obtained nanoparticles were single-phase SnS2 with hexagonal structure. These nanoparticles self-assembled to produce spherical 40-50 nm nanostructures after ethanol evaporation, whilst rhombohedral-shaped nanostructures or round-edge nanoribbons were produced after the toluene evaporation. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

In order to obtain low-k dielectric films, a subtractive technique, which removes sacrificial porogens from a hydrogenated silicon oxycarbide (SiOC:H) film, has been used successfully by different groups in the past. In this paper, we report on the porogen removal from porogenated SiOC:H films, using a hot wire chemical vapor deposition (HWCVD) equipment. Molecular hydrogen is dissociated into atomic hydrogen by the hot wires and these atoms may successfully remove the hydrocarbon groups from the porogenated SiOC:H films. The temperature of the HWCVD filaments proved to be a determining factor. By Fourier transform infrared spectroscopy, X-ray reflectivity (XRR), secondary ion mass spectrometry (SIMS), ellipsometric porosimetry and capacitance-voltage analyses, it was possible to determine that for temperatures higher than 1700 °C, efficient porogen removal occurred. For temperatures higher than 1800 °C, the presence of OH groups was detected. The dielectric constant was the lowest, 2.28, for the samples processed at a filament temperature of 1800 °C, although porosity measurements showed higher porosity for the films deposited at the higher temperatures. XRR and SIMS analyses indicated densification and Tungsten (W) incorporation at the top few nanometers of the films.

This work presents a study of the changes in the optical, morphological and compositional properties of SiOC thin films obtained by hot wire chemical vapor deposition (HWCVD) technique. A mixture of hydrogen (H 2 ), oxygen (O 2 ) and monomethyl-silane (MMS) was used as reactant gas, which was passed through a tantalum filament (Ta) in order to be decomposed and obtained the film. Changes were made in the oxygen concentration into the reactor to observe its influence on the luminescent properties of the obtained films. From FTIR absorption spectra of the films was possible to identify absorption bands corresponding to Si-O, Si-C, Si-H and Si-OH bonds. It was observed that when deposition temperature increases, the intensities of the absorption bands of the species H and OH also increase. On the other hand, from the SEM images it was observed an increase in the grain size when oxygen flow is higher, while from ellipsometry and EDS results it was observed that exist incorporation of Ta when higher oxygen flow is used. The presence of Ta in our films can be due to the degradation of the filament during the deposition. Besides, all samples obtained at low oxygen flows presented a very low emission, while those obtained at higher flow presented a wide and intense band emission in the visible spectrum, even though, it has not been possible to identify if the emission is due to effects of quantum confinement or defects in the SiO x matrix.

The dietary constituent, resveratrol, was recently identified as a transient receptor potential ankyrin 1 (TRPA1) antagonist, voltage-dependent sodium ion (Na+ ) channel, and cyclooxygenase-2 (COX-2) inhibitor. The aim of the present study was to investigate whether pretreatment with resveratrol attenuates acute inflammation-induced sensitization of nociceptive processing in rat spinal trigeminal nucleus caudalis (SpVc) and upper cervical (C1) dorsal horn neurons, via c-fos immunoreactivity. Mustard oil (MO), a TRPA1 channel agonist, was injected into the whisker pads of rats to induce inflammation. Pretreatment with resveratrol significantly decreased the mean thickness of inflammation-induced edema in whisker pads compared with those of untreated, inflamed rats. Ipsilateral of both the superficial and deep laminae of SpVc and C1 dorsal horn, there were significantly more c-fos-immunoreactive SpVc/C1 neurons in inflamed rats compared with naive rats, and resveratrol pretreatment significantly decreased that number relative to untreated, inflamed rats. These results suggest that systemic administration of resveratrol attenuates acute inflammation-induced augmented nociceptive processing of trigeminal SpVc and C1 neurons. These findings support resveratrol as a potential therapeutic agent for use in alternative, complementary medicine to attenuate, or even prevent, acute trigeminal inflammatory pain.

The use of the term "availability" to describe a photovoltaic (PV) system and power plant has been fraught with confusion for many years. A term that is meant to describe equipment operational status is often omitted, misapplied or inaccurately combined with PV performance metrics due to attempts to measure performance and reliability through the lens of traditional power plant language. This paper discusses three areas where current research in standards, contract language and performance modeling is improving the way availability is used with regards to photovoltaic systems and power plants.

Nezahualcoyotl es el segundo municipio mas poblado del Estado de Mexico. La marginacion es una cuestion social de gran influencia para el desarrollo urbano. Se planteo un estudio para analizar la intervencion de la percepcion social en la factibilidad de una transicion energetica basada en tecnologia fotovoltaica para el municipio, por medio de tecnicas socioestadisticas. La hipotesis supone diferentes tendencias de la poblacion (dependiendo del nivel de marginacion), para aceptar nuevas tecnologias energeticas e impulsar el bienestar de su comunidad. Se evaluaron las interacciones sociales y se analizo la estructuracion de la percepcion ambiental y economica sobre la energia solar. Se encontro que el nivel de marginacion, los costos de la energia electrica y el conocimiento de nuevas tecnologias son factores que influyen la transicion energetica en el municipio. Existe desinformacion sobre las consecuencias de una transicion energetica. La representacion local de nuevas tecnologias es fragil y las prioridades sociales estan vinculadas estrechamente con las comodidades domesticas.

Minimal deviation adenocarcinoma (MDA) is defined as an extremely well differentiated variant of endocervical adenocarcinoma. Several reports have stated that MDA associates with lobular endocervical glandular hyperplasia (LEGH). It is difficult to distinguish LEGH from MDA based on clinical and histologic similarities. There is no definite evidence proving that LEGH is a precursor lesion of MDA. A 45-year-old woman was admitted to our hospital for minute investigation of her neurological disorder. The multiple-cystic lesion at the uterine cervix was identified by magnetic resonance imaging. Based on her normal histological findings and severe underlying conditions, a careful follow-up strategy was adapted. Two years later, atypical glandular cells were observed and the multiple-cystic lesion had increased. Pathological diagnosis of a conization specimen was MDA. Radical hysterectomy was carried out. Pathological examination revealed coexistence of LEGH and MDA. Her clinical course and histological findings suggested the possibility that LEGH might be a precursor lesion of MDA.

A previous multi-center validation study demonstrated high transferability and reliability of reactive oxygen species (ROS) assay for photosafety evaluation. The present validation study was undertaken to verify further the applicability of different solar simulators and assay performance. In 7 participating laboratories, 2 standards and 42 coded chemicals, including 23 phototoxins and 19 non-phototoxic drugs/chemicals, were assessed by the ROS assay using two different solar simulators (Atlas Suntest CPS series, 3 labs; and Seric SXL-2500V2, 4 labs). Irradiation conditions could be optimized using quinine and sulisobenzone as positive and negative standards to offer consistent assay outcomes. In both solar simulators, the intra- and inter-day precisions (coefficient of variation; CV) for quinine were found to be below 10%. The inter-laboratory CV for quinine averaged 15.4% (Atlas Suntest CPS) and 13.2% (Seric SXL-2500V2) for singlet oxygen and 17.0% (Atlas Suntest CPS) and 7.1% (Seric SXL-2500V2) for superoxide, suggesting high inter-laboratory reproducibility even though different solar simulators were employed for the ROS assay. In the ROS assay on 42 coded chemicals, some chemicals (ca. 19–29%) were unevaluable because of limited solubility and spectral interference. Although several false positives appeared with positive predictivity of ca. 76–92% (Atlas Suntest CPS) and ca. 75–84% (Seric SXL-2500V2), there were no false negative predictions in both solar simulators. A multi-center validation study on the ROS assay demonstrated satisfactory transferability, accuracy, precision, and predictivity, as well as the availability of other solar simulators.

Since June 2012, the Research Center of the National Polytechnic Institute (CINVESTAV), located at Mexico City has installed 60 kilowatt-peak (kWp) photovoltaic (PV) system. PV system energy performances are reported together with the measured solar irradiation, PV module temperature and wind velocity. The grid-connected PV system consists of 240 PV modules of 250 Wp each, which are connected to 5 inverters to convert three phase 240 VAC. The injected energy to the grid, is used mainly for the building illuminations. We report the general PV system electric performances as a function of the seasonal solar irradiation and whether variations. The produced average energy during June 2012, was about 250 kWh/day, with a minimum and maximum of 100 and 350 kWh/day, respectively. In the same month, the PV module average operating temperature was between 55 to 62 °C. The best energy produced month was February 2013 with 310 kWh as daily-based average.

In this manuscript, distinct approaches were used in order to obtain the best electrical power estimation from photovoltaic systems located at different selected places in Mexico. Multiple Linear Regression (MLR) and Gradient Descent Optimization (GDO) were applied as statistical methods and they were compared against an Adaptive Neuro-Fuzzy Inference System (ANFIS) as an intelligent technique. The data gathered involved solar radiation, outside temperature, wind speed, daylight hour and photovoltaic power; collected from on-site real-time measurements at Mexico City and Hermosillo City, Sonora State. According to our results, all three methods achieved satisfactory performances, since low values were obtained for the convergence error. The GDO improved the MLR results, minimizing the overall error percentage value from 7.2% to 6.9% for Sonora and from 2.0% to 1.9% for Mexico City; nonetheless, ANFIS overcomes both statistical methods, achieving a 5.8% error percentage value for Sonora and 1.6% for Mexico City. The results demonstrated an improvement by applying intelligent systems against statistical techniques achieving a lesser mean average error.

In this study, the relation among different meteorological variables and the electrical power from photovoltaic systems located at different selected places in Mexico were presented. The data was collected from on-site real-time measurements from Mexico City and the State of Sonora. The statistical estimation by the gradient descent method demonstrated that solar radiation, outdoor temperature, wind speed, and daylight hour influenced the electric power generation when it was compared with the real power of each photovoltaic system. According to our results, 97.63% of the estimation results matched the real data for Sonora and 99.66% the results matched for Mexico City, achieving overall errors less than 7% and 2%, respectively. The results showed an acceptable performance since a satisfactory estimation error was achieved for the estimation of photovoltaic power with a high determination coefficient R2.

Aim: We evaluated the long-term effects of olmesartan, an angiotensin type 1 receptor blocker, in patients with non-alcoholic steatohepatitis (NASH) complicated with hypertension. Methods: All patients were given a standard calorie diet and exercise counseling more than 3 months before the treatment. Seven patients with NASH received olmesartan treatment for 1 year. Liver biopsy, clinical parameters and blood markers of hepatic fibrosis, including serum hyaluronic acid, type IV collagen, and procollagen III N-terminal propeptide levels, were also examined at the beginning and the end of the study. Results: The median dose of the final administration was 20 mg (range, 10 - 40 mg). Olmesartan reduced MAP by –11.3 ± 13.0% (P = 0.046) after 1 year. In the laboratory data, serum AST, ALT, and ferritin significantly decreased after a year of administration (AST, 62 ± 24 vs. 39 ± 20 IU/L, P = 0.018; ALT, 106 ± 79 vs. 55 ± 35 IU/L, P = 0.043; ferritin, 323.8 ± 252.8 vs. 202.3 ± 194.1 ng/ml, P = 0.028). Furthermore, fasting glucose significantly decreased. However, transforming growth factor-beta1, the serum concentration of the fibrosis markers, and all histological features were unchanged at the end of the study. No side effects of the treatment were noted at any time during the study. Conclusion: Olmesartan significantly reduced blood pressure, fasting glucose, aminotransferase, and serum ferritin but could not suppress the hepatic fibrosis markers or histological features after 1 year. Therefore, olmesartan is advisable only for its anti-inflammatory effect in patients with NASH-complicated hypertension.

The impact of the surface reconstruction of the density distribution and photoluminescence of silicon quantum dots (QDs) embedded in a silicon oxide matrix (SiOx) has been studied. Annealing treatments carried out on the as-deposited samples provoked the effusion of hydrogen species. Moreover, depending on the surrounding density and coalescence of QDs, they resulted in a change in the average size of the particles depending on the initial local environment. The shift in the luminescence spectra all over the visible region (blue, green and red) shows a strong dependence on the resultant change in the size and/or the passivation environment of QDs. Density functional theoretical (DFT) calculations support this fact and explain the possible electronic transitions (HOMO–LUMO gap) involved. Passivation in the presence of oxygen species lowers the band gap of Si29 and Si35 nanoclusters up to 1.7 eV, whereas, surface passivation in the environment of hydrogen species increases the band gap up to 4.4 eV. These results show a good agreement with the quantum confinement model described in this work and explain the shift in the luminescence all over the visible region. The results reported here offer vital insight into the mechanism of emission from silicon quantum dots which has been one of the most debated topics in the last two decades. QDs with multiple size distribution in different local environments (band gap) observed in this work could be used for the fabrication of light emission diodes (LEDs) or shift-conversion thin films in third generation efficient tandem solar cells for the maximum absorption of the solar spectrum in different wavelength regions.

This work presents the advances in the synthesis and characterization of magnetite-graphene oxide nanocomposite synthetized by coprecipitation. Structural and physicochemical properties were analyzed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM) and vibrating sample magnetometer (VSM). XRD and FT-IR analyses corroborated that magnetite was obtained. Nanoparticle mean size from XRD analysis revealed that it decreased when graphene oxide (GO) was present. TEM displayed that magnetite decorates the GO and VSM revealed superparamagnetic behavior.

Thin films comprising vertical aligned ZnO nanorod arrays are currently used for sensing and photovoltaic applications. Chemical Bath Deposition (CBD) is a low-cost technique for the semiconductor thin films deposition. This work reports the CBD growth of ZnO nanorods (NRs) on different substrates for potential application in thin film solar cells. It was found that, the successful deposition of thin films composed of vertical aligned ZnO nanorods on bare and ITO-coated glass substrates strongly depends on the seed layer characteristics.

In this work, we have investigated the structural, morphological, and optical properties of ZnO thin films by placing the substrate at different locations of the substrate holder. ZnO thin films were grown on glass substrates by reactive radio frequency (RF) sputtering at 100W. Structural results obtained from XRD revealed that ZnO thin films were grown along (002) plane. Morphological studies showed that films were formed from nanograins of ZnO. Optical measurements in the UV-vis region presented an average transmittance >90%.

In the Research Center (CINVESTAV), located north Mexico City was evaluated a 60 kWp photovoltaic (PV) system. The PV system energy performance ratio (PR) is reported together with the measured solar irradiation, ambient and PV module temperatures for three years. A finally calculated average PR was 86.8% for the 36 months. The average daily energy produced by the PV system during 3 years was 260.45 kWh/day and an average accumulated energy of 95,064.25 kWh per year. If we consider the factor of 1% degradation per year in the generated power, the system will generate about 1,311,887 kWh after 15 years, or equivalent to 87,459 kWh as an average per year.

This work describes the formation of reduced graphene oxide-coated copper oxide and copper nanoparticles (rGO-Cu2ONPs, rGO-CuNPs) on the surface of a copper foil supporting graphene oxide (GO) at annealing temperatures of 200–1000 °C, under an Ar atmosphere. These hybrid nanostructures were developed from bare copper oxide nanoparticles which grew at an annealing temperature of 80 °C under nitrogen flux. The predominant phase as well as the particle size and shape strongly depend on the process temperature. Characterization with transmission electron microscopy and scanning electron microscopy indicates that Cu or Cu2O nanoparticles take rGO sheets from the rGO network to form core–shell Cu–rGO or Cu2O–rGO nanostructures. It is noted that such ones increase in size from 5 to 800 nm as the annealing temperature increases in the 200–1000 °C range. At 1000 °C, Cu nanoparticles develop a highly faceted morphology, displaying arm-like carbon nanorods that originate from different facets of the copper crystal structure.