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Globally, the transport sector represents more than a quarter of the total energy consumed. In Mexico, energy consumption in the road transport subsector alone represented 40.9% of the final energy required nationwide. The national goal of energy efficiency expressed in terms of energy intensity for the transport, industry, buildings, and agricultural sectors, indicates that energy intensity should decrease 1.9% per year during the 2016–2030 period. Besides, the primary strategy proposed by the government to optimize the energy consumption of freight transportation is energy efficiency. This proposal estimates the energy efficiency indicators to make a reliable assessment of the situation of the impact of energy efficiency on demand. If the goal of reducing the transport sector energy intensity is met, the intensity of freight transportation should be reduced from 0.7434 MJ / dollar in 2017 to 0.5793 MJ / dollar by 2030, which represents a reduction of 22.1%. It could represent a reduction in carbon emissions of 33.1% in the same period.

Four new quinoxaline-spanned cavitands having a diester hydrogen phosphate group were successfully synthesised. These phosphorous derivatives were applied in Brønsted acid-assisted catalytic conjugate addition reactions. The results were ranked with the control of diphenyl hydrogen phosphate as well as among those four cavitands. The structure–activity relationship revealed that the catalyst centre surrounded by two trans-positioned quinoxalines significantly influences reaction profile and product distribution. This comparative study provides us an intellectual basis for future catalytic cavitand chemistry and artificial enzymatic catalysis.

Cu2ZnSnS4 (CZTS) thin films were deposited on glass-slide substrates by ultrasonic spray pyrolysis at the substrate temperatures in the 330–420 °C range, using water–ethanol solutions containing CuCl2–H2O, ZnCl2, SnCl2, and (NH2)2CS (thiourea). After being deposited, CZTS films were annealed under vacuum and then characterized in regarding their structural and optical properties. The X-ray diffraction and Raman spectroscopy studies indicated that CZTS thin films with kesterite as predominant phase could be obtained. The X-ray diffraction patterns of all deposited samples displayed diffraction peaks corresponding to the planes (112), (220), and (312) of kesterite CZTS and diffraction peaks belonging to phases other than CZTS were apparently undetectable for the X-ray technique. Furthermore, their Raman spectra were featured for a widely structured Raman band in the 200–400 cm−1 wavenumber area. After being deconvoluted, Raman peaks belonging only to kesterite CZTS were revealed. However, a further analysis of the UV–Vis absorbance spectra indicated all our films strongly absorbs in this spectral region. In the low photon energy region (

The 2018 Mw 6.4 Hualien earthquake generated a large peak-to-peak velocity of over 2 m/s, with a period of 3 s at the south end of the Milun fault, which resulted in the collapse of five buildings. To investigate the shallow subsurface soil structure and evaluate possible effects on the ground motion and building damage, we performed microtremor measurements in the Hualien basin. Based on the velocity structure jointly inverted from both Rayleigh-wave dispersion curves and microtremor horizontal-to-vertical spectral ratio data, we found that the shallow subsurface structure generally deepens from west to east. Close to the Milun fault, the structure becomes shallower, which is consistent with faulting during the 2018 earthquake and the long-term tectonic displacement. There is no significant variation for the site conditions in the north–south direction that can explain the large peak ground velocity in the south. As a result of the dense measurements in the heavily damaged area, where three high-rise buildings totally collapsed, these locations have the average S-wave velocity of the upper 30 m (AVS30) values and are relatively high compared to the more distant area from the Meilun River. This is somewhat unusual, because lower AVS30 values indicating softer ground conditions are expected close to the river. We did not find any characteristic subsurface soil structure that may contribute to the building collapses. The large 3 s pulse was probably generated by source effects, rather than subsurface soil amplification.

The purpose of this work was to produce iron nanoparticles (Fe-NP) by microbial pathway from anaerobic bacteria grown in anaerobic fluidized bed reactors (AnFBRs) that constitute a new stage of a waste-based biorefinery. Bioparticles from biological fluidized bed reactors from a biorefinery of organic fraction of municipal solid wastes (that produces hydrolysates rich in reducing sugars) were nanodecorated (embedded nanobioparticle or nanodecorated bioparticle, ENBP) by biological reduction of iron salts. Factors “origin of bioparticles” (either from hydrogenogenic or methanogenic fluidized bed reactor) and “type of iron precursor salt” (iron chloride or iron citrate) were explored. SEM and high-resolution transmission electron microscopy (HRTEM) showed amorphous distribution of nanoparticles (NP) on the bioparticles surface, although small structures that are nanoparticle-like could be seen in the SEM micrographs. Some agglomeration of NPs was confirmed by DLS. Average NP size was lower in general for NP in ENBP-M than ENBP-H according to HRTEM. The factors did not have a significant influence on the specific surface area of NPs, which was high and in the range 490 to 650 m2 g−1. Analysis by EDS displayed consistent iron concentration 60–65% iron in nanoparticles present in ENBP-M (bioparticles previously grown in methanogenic bioreactor), whereas the iron concentration in NPs present in ENBP-H (bioparticles previously grown in hydrogenogenic bioreactor) was more variable in a range from 8.5 to 62%, depending on the iron salt. X-ray diffraction patterns showed the typical peaks for magnetite at 35° (3 1 1), 43° (4 0 0), and 62° (4 0 0); moreover, siderite diffraction pattern was found at 26° (0 1 2), 38° (1 1 0), and 42° (1 1 3). Results of infrared analysis of ENBP in our work were congruent with presence of magnetite and occasionally siderite determined by XRD analysis as well as presence of both Fe+2 and F+3 (and selected satellite signal peaks) observed by XPS. Our results on the ENBPs hold promise for water treatment, since iron NPs are commonly used in wastewater technologies that treat a wide variety of pollutants. Finally, the biological production of ENBP coupled to a biorefinery could become an environmentally friendly platform for nanomaterial biosynthesis as well as an additional source of revenues for a waste-based biorefinery.

Objectives: Colorectal laterally spreading tumors (LSTs) are widely recognized owing to their structural characteristics. This study aims to clarify the histopathological characteristics of large colorectal LSTs according to growth pattern. Methods: We studied 297 colorectal LSTs measuring ≥20 mm in diameter. The LSTs were classified into four types: granular homogenous type (LST-G-H), granular nodular mixed type (LST-G-M), non-granular flat elevated type (LST-NG-F), and non-granular pseudo-depressed type (LST-NG-PD). Retrospectively collected data were examined to compare the histopathological characteristics of LSTs according to the growth pattern. Results: LST-G-M lesions (142 lesions) were most common, followed by LST-NG-F (74 lesions), LST-G-H (61 lesions), and LST-NG-PD (20 lesions). The mean tumor diameter of LST-G lesions (38.5 ± 17.2 mm) was significantly greater than that of LST-NG lesions (26.3 ± 7.0 mm, P < 0.001). In particular, 45% of LST-G-M lesions were ≥40 mm in diameter. Adenomas accounted for 54% of LST-G-H lesions compared with only 10% of LST-NG-PD lesions. Pathological T1 carcinomas accounted for 55% of LST-NG-PD lesions and were not found among LST-G-H lesions. Conclusions: The biological malignancy of colorectal LSTs differs considerably depending on the growth pattern even among large lesions and therefore should be considered when selecting treatment regimens.

Strong ground motions from the 2016 Mw 7.0 Kumamoto earthquake (Japan) can be well simulated based on a characterized source model consisting of strong-motion generation areas (SMGAs) with high stress drop and a background area with low stress drop, except at very near-fault stations (Irikura et al. in Earth Planets Sp 69:10, 2017). Strong ground motions observed at very near-fault stations less than 3 km away from the surface traces along the Futagawa fault zone have long-period motions including maximum permanent displacements beyond 2 m. To reproduce such long-period ground motions at those very near-fault stations, one must place SMGAs in the seismogenic zone but also add long-period-motion generation areas (LMGAs) in the weak shallow layer (SL) zone between the top of the seismogenic zone and the free surface. During the 2010 Mw 7.0 Darfield (New Zealand) earthquake, surface breaks caused by the mainshock were found associated with active faults by field surveys. Strong ground motions from the 2010 Darfield earthquake can also be simulated well using the conventional characterized source model, except for ground motions at very near-fault stations. Reproduction of very near-fault motions with permanent components for the 2010 Darfield earthquake also requires consideration of LMGAs in the SL zone. We thus propose an extension of the characterized source model by adding LMGAs in the SL zone. The parameters for the SMGAs are given following the recipe of Irikura and Miyake (Pure Appl Geophys 168:85–104, 2011), while the parameters of the LMGAs are estimated from two scaling relationships, viz. the surface displacement versus the average slip in the rupture area from the source inversion, and the surface displacement versus the rise time of the slip velocity time function in the LMGA from the forward simulation.

Silicon (Si) and silicon carbide (SiC) nanoparticles embedded in an amorphous matrix of SiO xCy were grown using a very safe and economic precursor, tetra-ethyl orthosilicate (TEOS-(Si(OC2H5)4 )) by an organic catalytic chemical vapor deposition technique (O-Cat-CVD) at a relatively low filament temperature of 1700 °C and a substrate temperature of 300 °C. These crystalline nanoparticles were generated during the growth process in the thin film matrix, without the need for any post-annealing treatment. Morphology and crystalline phase identification of the nanoparticles were studied using Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) respectively. X-ray Photoelectron Spectroscopy (XPS) and Fourier transform infrared (FTIR) revealed the presence of Si, O, C presence in the matrix and additionally different bonding peaks such as Si O Si rocking, Si C stretching, Si H bending, Si OH, Si O Si antisymmetric stretching, Si CH3 bending, C C and C H modes confirmed the formation of SiOxCy matrix. Optical studies were carried out using the photoluminescence spectroscopy , and broad, intense visible emission was observed from the sample. Further, investigation of the luminescence mechanism was carried out using the time-resolved photoluminescence (TRPL) and low-temperature photoluminescence (LTPL). The decay time was found in the order of few nanoseconds, which remarked that the emission is mainly from the radiative recombination inside the Si and SiC nanoparticles embedded in SiOxCy matrix and was attributed to the quantum confinement effect (Q.C.E). Additional, measurements were carried out by varying the laser pump power, and two extreme powers (low pump power, 2 mW, and high pump power, 30 mW) were used to find their impact on the emission. As in overall, the emission found in the present study can be used to develop potential applications such as LED, the third generation of solar cells among others.

Asperity models for ground motion prediction is widely used in Japan. Here we expand the application of these asperity models to predict fault displacement caused by surface rupture. The proposed approach is rather simple and practical for the use in fault displacement hazard analysis in nuclear installations and other critical infrastructures, as it is the emphasis of the current topical issue. The proposed method mainly consists of two steps. The first step consists in the characterization of asperities at the seismogenic zone based on the kinematic asperity source model following Irikura’s recipe (Irikura and Miyake in Pure Applied Geophysics, 168:85–104, 2011) for strong ground motion prediction. Since the kinematic model does not take into account surface rupture mechanism, this first step assumes that the fault is buried, and then by trial and error procedure the stress drop on the asperities are estimated, so that the average slip at each asperity be consistent with the ones from the kinematic model. At this stage, the dynamic model predicts strong ground motion consistent with those from the kinematic model. In the second step, the surface rupture is included by calibrating the shallow layer (SL) with stress drop, strength excess and critical slip distance, so that the final fault displacement along the fault be consistent with observations. The 2010 Mw 7.0 Darfield (New Zealand) earthquake is used to test the proposed method. Surface-rupturing was observed in several sites along the main fault reaching values of fault displacement larger than 5 m. The main fault of this earthquake is strike-slip, almost vertical. Therefore, a simplified planar fault asperity model to capture the main features of the fault displacement is assumed. The fault dimensions are assumed to have a length of 60 km and a width of 24 km with three asperities. The preferred model of the first step predicts average slip for each asperity of 2.7, 2.7, and 2 m corresponding, respectively, to stress drops of 6.0 MPa, 8.5 MPa, and 7.0 MPa. In the second step, the surface rupture is calibrated assuming a SL zone of 3 km depth. We found that negative stress drop is not necessary in the SL, because this strongly inhibits surface rupturing. Our preferred model produces fault displacement distribution closer to the observed ones, but average slip at each asperity increases to 3.4 m, 3.2 and 2.8 m. This increase in average slip is due to the contribution of surface rupturing. Ground motion differences between fault-surface rupturing and buried models are negligible, except at the very near-source. These differences are attributed to the SL rupture that mainly affect the ground motion at the very near-source. Overall, our simple asperity model captures the main features of the observed fault displacement and near-source ground motion, proving that the proposed simple and practical two step-procedure provides meaningful estimate of fault displacement and near-source ground motion consistent with observations, as such, this method has the potential to be used in practical fault displacement hazard analysis.

In the Research Center (CINVESTAV), located north Mexico City was evaluateda 60 kWp photovoltaic (PV) system. The PV system energy performance ratio, so called “quality factor” isreported together with the measured solar irradiation,ambient andPV module temperatures. The performance ratio (PR), defines the overall PV system performance considering operation parameters as the produced energy, the incident solar irradiance and the total effect of system losses. The electric grid-tied PV system consists of 240 PV modules of 250 Wp each, which are connected to 5 inverters to transform three phase AC. We describe the PV system electric performance for 36 consecutive months through diverse weather conditions. The calculated average PR was 86.8% for the 36 months, even though,it had a lower PR of about 84.8 % in the last 12 months due to the PV array string outages and also inverter technical troubles. The average daily energy produced by the PV system in 3 years was 260.45 kWh/day and anaverage accumulated energy of 95,064.25 kWh per year.

Various experiments, such as X-ray diffraction, polarization microscopy, relative permittivity, spontaneous electric polarization and ferroelectric loop measurements, have been performed on single crystals of a perovskite-type layered compound ( C 2 H 5 N H 3 ) 2 C u C l 4 . The crystal structure of this compound at 273 K and 100 K is determined as Abma and Pbca, respectively. In the polarization microscopy experiments, disappearance of the ferroelastic domain under a stress has been found at 370 K, suggesting that the crystal structure above 370 K is tetragonal (I4∕mmm). We have found, for the first time, a remarkable anomaly at T C = 25.8 K in the temperature dependence of the relative permittivity. In D-E hysteresis measurements, the ferroelectric loop opens below T C, where D is the electric displacement field and E is the electric field, respectively. The remnant polarization reaches 8 μC/m2 at 5 K. These results indicate that there is a weak ferroelectric ordering at T C. The clear D-E hysteresis curve is detected below T N = 10 K, which is a weak ferromagnetic transition temperature, suggesting that the weak ferroelectric and the weak ferromagnetic states coexist below T N.

Performance ratio (PR) of 60 kWp photovoltaic system (PVS) were measured considering the soiling effect in the interval of December 2019 to January 2020. Towards final week of December 2019, the PVS started showing a poor PR due to the natural soiling in a photovoltaic-array, but due to rainfall at mid-January 2020, the PR was recuperated. The average PR for January was 71.1%, but the cleaned PV-array by the rainfall showed an about 14 points of increment in energy generation from 63.3 to 77.3 %. Also, it is discussed the average generated energy during 2019 which was 267.8 kWh/day and in 2020, it was 273.3 kWh/day, with the corresponding PR of 76.7% and 76.8%, respectively.

This work aims to evaluate the properties of deposited SiO x C y thin films by means of organic catalytic chemical vapor deposition (O-Cat CVD) technique. The employed precursors were Monomethyl Silane (MMS; (CH 3 -SiH 3 )) and Tetra-ethyl orthosilicate [TEOS; (Si(OC 2 H 5 ) 4 )], which corresponded to gaseous and liquid sources, respectively. The deposition chamber worked under a reactant atmosphere of hydrogen (H 2 ) and oxygen (O 2 ), likewise the use of tantalum (T a ) as a catalyst for MMS precursor. TEOS was used at the Argon atmosphere and tungsten (W) as a catalyst. The deposition time was varied from 20 to 30 min in order to evaluate its influence on the luminescent properties of the deposited films. Chemical and bonding-state characterization were performed through Fourier transform infrared (FTIR) and X-ray Photoelectron Spectroscopy (XPS) techniques. The measurements of thickness and refractive index of the thin films were obtained by ellipsometry. Optical properties were evaluated by photoluminescence spectroscopy. The FTIR showed the peak shifting from the stoichiometric stretching value of Si-O-Si bonding (1080 cm-1) to 1025 cm-1 and 1036 cm-1 for MMS and TEOS precursors, respectively. The Si-O-Si bonding shift might come due to the oxygen deficiency in the prepared samples. Through XPS measurements, it was possible to determine different bonding states and their amount through the formation of SiO x C y thin films; however, the sample deposited with TEOS shows its nature closer to the SiO x phase in comparison to MMS deposited thin films. The thickness of thin films increased proportionately with the increment of deposition time. Moreover, the red-shifted PL spectrum was determined for the MMS deposited samples in comparison to TEOS deposited samples. Intense emission in a broad region of the visible spectrum was observed without further thermal annealing process. The different reasons were discussed about the origin of photoluminescence, but still, there is further need for additional studies to determine the PL mechanism.

During 2018 and 2019, it was evaluated a 60 kWp photovoltaic (PV) system. The PV system energy performance ratio is reported together with the measured solar irradiation, wind velocity, ambient and PV module temperatures. The performance ratio (PR) is a straightforward indicator to compare different PV systems through the produced energy, considering its total system losses. The obtained average PR during 2018 was 76.27%, and in 2019 it was 77.70%. The lower PR in 2018 was mainly due to the one of the inverters partial failure. Even though, the soiling effects on the PV module-array lowered substantially the PR of about 10% of the energy to obtain. The average daily produced energy by the PV system during 2-years was 263.75 kWh/day with an average daily solar irradiance of 5.71kWh/m2 and the total produced energy during 24-consecutive months was 192,537.94 kWh with the overall PR of 76.985%.