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The largest seismic event ever recorded on Mars, with a moment magnitude of 4.7 ± 0.2, is the first event to produce both Love and Rayleigh wave signals. We measured their group velocity dispersion between about 15 and 40 s period and found that no isotropic depth‐dependent velocity model could explain the two types of waves wave simultaneously, likely indicating the presence of seismic anisotropy. Inversions of Love and Rayleigh waves yielded velocity models with horizontally polarized shear waves traveling faster than vertically polarized shear waves in the top 10–25 km. We discuss the possible origins of this signal, including the preferred orientation of anisotropic crystals due to shear deformation, alignment of cracks, layered intrusions due to an impact, horizontal layering due to the presence of a large‐scale sediment layer on top of the crust, and alternation of sedimentation and basalt layers deposits due to large volcanic eruptions. Plain Language Summary: The largest marsquake recorded so far sent energy across the red planet in the form of different kinds of waves, including two types of waves trapped near the surface. This was the first time both types of so‐called surface waves were detected on Mars. Combining measurements from these two types of surface waves allowed us to determine the speed of other types of waves, that is, waves that travel horizontally and that make rocks move perpendicular to the direction of propagation. We found that these waves move faster in the crust between 10 and 25 km depth when the rocks oscillate in a direction sub‐parallel to the planet surface than if the rocks vibrate in the vertical direction. This wave speed dependence can tell us about deformation mechanisms inside the crust. We found that either an alternation of volcanic rocks and sediments layers due to volcanic eruptions or internal layering within the crust due to an impact are the preferred explanations for our observations. Key Points: Rayleigh and Love waves were detected on MarsSeismic wave speed is directionally dependent over large‐scales within Mars crustThe shear wave horizontal velocity is faster than the vertical velocity at 10–25 km depth in the lowlands between the event and the lander [ABSTRACT FROM AUTHOR]

X-ray diffraction patterns of decagonal Al[sub 70]Co[sub 15]Ni[sub 15], Al[sub 72]Ni[sub 12]Co[sub 16] and Al[sub 62]Cu[sub 20]Co[sub 15]Si[sub 3] show, apart from 'sharp' reflections, prominent diffuse maxima and diffuse streaks. From an analysis of high-resolution synchrotron data, arguments are given in favour of a more uniform interpretation of all these phenomena in terms of linear phason strain and phason fluctuations. Thus structural modifications, including one-dimensional quasicrystalline domains and periodic domains (approximants) can be conveniently described as transient ordering states, depending on temperature and composition. [ABSTRACT FROM AUTHOR]

Diffuse layers which are observed in different decagonal quasicrystals perpendicular to the unique 'periodic' axis are explained by one-dimensional (1D) columns of icosahedral Al clusters along this axis. From results of X-ray and purely elastic neutron diffraction experiments we give a qualitative explanation by basically off-layer atomic displacements which are grossly uncorrelated in different columnar clusters. A reversible temperature behaviour of the 1D superstructure which vanishes at high temperatures can be understood in the framework of this interpretation. Diffuse intensity modulations within the diffuse layers are discussed in terms of atomic displacements and chemical ordering within the icosahedral clusters which are the basic structural units of the columns. Computer simulations of different columnar models are carried out, their Fourier transforms are compared with the observed patterns. [ABSTRACT FROM AUTHOR]

The resistance of several models of catalytic, workfunction-based metal-oxide-semiconductor and electrochemical hydrogen sensors to chemical contaminants such as SO 2, H 2 S, NO 2 and hexamethyldisiloxane (HMDS) has been investigated. These sensor platforms are among the most commonly used for the detection of hydrogen. The evaluation protocols were based on the methods recommended in the ISO 26142:2010 standard. Permanent alteration of the sensor response to the target analyte (H 2 ) following exposure to potential poisons at the concentrations specified in ISO 26142 was rarely observed. Although a shift in the baseline response was often observed during exposure to the potential poisons, only in a few cases did this shift persist after removal of the contaminants. Overall, the resistance of the sensors to poisoning was good. However, a change in sensitivity to hydrogen was observed in the electrochemical platform after exposure to NO 2 and for a catalytic sensor during exposure to SO 2 . The siloxane resistance test prescribed in ISO 26142, based on exposure to 10 ppm HMDS, may possibly not properly reflect sensor robustness to siloxanes. Further evaluation of the resistance of sensors to other Si-based contaminants and other exposure profiles (e.g., concentration, exposure times) is needed. [ABSTRACT FROM AUTHOR]

High-resolution synchrotron data of near-Bragg diffuse scattering from decagonal Al71.5Ni23.5Fe5 quasicrystals were recorded. A dominant phasonic origin is ruled out because of the absence of a significant G⊥ dependence. An analysis solely in the frame of thermal diffuse scattering (TDS) theory (phonon scattering) showed a good match between experimental and calculated data in the quasiperiodic layers, but with an improbable ratio of elastic constants, c66/c11 = 4.0. In situ high-temperature measurements up to 1000 K revealed an increase of the intensity distribution perpendicular to the scattering vector G. Huang diffuse scattering (HDS) arising from quenched local defects has a general appearance that qualitatively reproduces the observed symmetry and anisotropy. An interpretation based on both TDS and HDS contributions is given. [ABSTRACT FROM AUTHOR]

High resolution synchrotron x-ray data of near-Bragg diffuse scattering from decagonal Al71.5Ni23Fe5quasicrystals was recorded. A significant dependence on Qbotwas not observed, a dominant phasonic origin can thus be ruled out. An analysis in frame of a TDS theory gives an unlikely ratio of elastic constants c66/c11=4.0. Moreover, subsequent measurements up to 720 K do not reveal a pronounced intensity increase. Predictions of a theory of Huang diffuse scattering, however, nicely match the anisotropy of the measured data. [ABSTRACT FROM AUTHOR]

This research was designed to evaluate the performance of the CuFe12O19/CuS/Xenon system in the degradation of tetracycline in aqueous solutions. In this study, after green synthesis of nanocomposite using the extract of the Artemisia plant, its properties were determined by XRD, FTIR, FESEM, TEM, BET, XPS, DRS, DLS, EDS, VSM, and PL. In addition, parameters affecting the photocatalytic degradation of tetracycline, including time, pH, TC initial concentration, and nanocomposite dose, were assessed. The findings showed that the degradation efficiency increases with increasing pH and catalyst dosage. Under optimum circumstances (pH = 9, nanocomposite dose of 0.5 g/L, and time 200 min), the process efficiency with concentration of 20 mg/L was 100%. The kinetics of the degradation rate of tetracycline obeyed the pseudo-first-order equation. In addition, the results show that after six consecutive cycles, the synthesized catalyst's ability did not significantly reduce. The results of the mineralization tests revealed that the COD and TOC degradation of the synthetic solution of tetracycline with a concentration of 20 mg/L reached 87.25% and 73.06%, respectively, in the optimal reaction conditions. The scavenger experiments confirmed that OH plays the most crucial role in the decomposition process of tetracycline. Generally, the CuFe12O19/CuS/Xenon photocatalytic system can effectively degradation tetracycline from aqueous environments. [ABSTRACT FROM AUTHOR]

Conventional leather chromium tanning requires long process time, excessive water usage and results in low float exhaustion of chrome salts. Our study aimed to eliminate the negative aspects of chromium tanning by designing a vacuum operated reaction vessel/drum and suitable production recipe for sheepskins. Tanning time decreased from 10 h to 6 h under vacuum. Float uptake was increased almost 30% according to the chrome oxide (Cr2O3) contents in leather and residual floats. Using the process water was also considerably saved. Process success was proved with Cr2O3 contents in leather and wastewater by chemical analyses after tanning operations. Shrinkage temperature (Ts) controls as hydrothermal stability indicator of collagen were also realized on the tanned skins. Pollution loads of conventional and vacuum operated chromium tanning were discussed with chemical oxygen demand (COD), total suspended solids (TSS), conductivity and salinity in the tanning baths. Physico-mechanical properties were also compared of the final products by tensile strength and tear load analyses. The results showed that vacuum operated chromium tanning was highly effective and promised for the sustainable production of leather products. [ABSTRACT FROM AUTHOR]

Globally, the companies that make commercial use of bamboo culms produce different kinds of solid waste rich in lignocellulosic biomass, which in some cases is not used and is discarded in landfills or incinerated in the open air; losing the possibility of recovering them and using them in other productive sectors. The research objective were to produce a biochar from Guadua agustifolia Kunth sawdust, evaluate its potential environmental and agricultural use, obtain a biochar/TiO2 composite to inactivate Escherichia coli and use the biochar as a soil conditioner in medicinal plants producing phenolic compounds and flavonoids. Biochar composite (produced at 300 °C for 1 h) involved TiO2 at 450 °C for 1 h for inactivation of E. coli (initial concentration: 6.5 ± 0.3 Log10 CFU mL− 1). For agriculture, 2% biochar was used to evaluate B. pilosa L. and G. angustifolia plant growth for 90 days. The biochar/TiO2 composite had a high photocatalytic activity on E. coli, generating a final count of 1.97 ± 0.2 Log10 CFU mL− 1 after 60 min. Biochar (2%) increased the total phenol and flavonoid content in the medicinal plant B. pilosa L. and total phenols in G. angustifolia, tested at the nursery stage. This study provides new information on the conversion and use of G. angustifolia sawdust as an alternative for new bio-based materials with environmental and agricultural applications. In addition, obtaining biochar and composite could positively impact the bamboo production chain in Colombia because of renewable and globally accepted alternatives that help capture gaseous emissions causing the greenhouse effect. [ABSTRACT FROM AUTHOR]

Nitrogen oxides (NOx) have numerous negative effects on both the environment and human health. They are major contributors to photochemical smog and acid rain. As a result, researchers are increasingly focused on developing de-NOx technologies. One effective method for removing NOx from the environment is selective catalytic reduction (SCR), with ammonia serving as the reductant (NH3–SCR). Rare earth-based catalysts have emerged as viable options for low-temperature NH3–SCR. Currently Ce-based NH3–SCR catalysts, such as CeO2–TiO2, CeO2–WO3, CeO2–MoO3, Ce–Mn–TiO2, CeO2–MnO2, Ce0.67Zr0.33O2, and CeO2–Fe2O3 have focused significant attention from researchers. The 4f orbitals of rare earth elements (REEs) are devoid of full electron occupancy. This attribute contributes to their distinct catalytic efficacy when employed as catalyst substrates. The oxygen storage capacity of Ce-based catalysts has further enhanced their popularity. Various methods, including microwave, hydrothermal, precipitation and sol–gel techniques, have been used by researchers to prepare catalysts in order to reduce the NOx emission. The paper has covered the impact of the preparation technique on rare earth catalyst performance and the NH3–SCR reaction mechanism to achieve a wide operating temperature. The global production and reserves of rare earth elements (REEs) worldwide have been thoroughly examined, and catalysts for the reduction of NOx emissions in automobiles by Ce and La have been explored. [ABSTRACT FROM AUTHOR]

Single-crystal X-ray diffraction was carried out on a decagonal Ni-rich phase in the Al-Co-Ni system with a nominal composition of Al72.5Co11Ni16.5. Apart from sharp Bragg reflections, satellite scattering was observed in Al72.5Co11Ni16.5 which is different from the satellite scattering observed in a Ni-poor phase with nominal composition Al72.5Co16.5Ni11. The two types of superorder scattering are interpreted in an unified way by periodic order superimposed on the quasiperiodic averaged substructure. This periodic regimes have a limited correlation length (short-range ordering). While the modulation period stays almost constant over a wide range of compositions in these decagonal alloys, the modulation vector is rotated by pi/10 if passing from Ni-rich (S satellites) to Ni-poor (C satellites) compositions. Arguments are given in favour of this interpretation which is also supported by computer simulations. [ABSTRACT FROM AUTHOR]

Development of supercritical carbon dioxide (SC-CO2) dyeing technology for natural fabrics and their blended fabrics is essential for the textile industry due to environmental and economic considerations. Wool (W), polyester (PET) and nylon (N) fabrics and their wool/polyester (W/PET) and wool/nylon (W/N) blended fabrics were dyed in SC-CO2 medium with a synthesized reactive disperse dye containing a vinylsulphone (VS) reactive group, which behaves as a disperse dye for synthetic fibers and a reactive dye for protein fibers. The SC-CO2 dyeing performance of all fabrics was investigated in terms of color strength, fixation, colorimetric and fastness measurements and compared with the conventional aqueous dyeing method. The results obtained indicate that the VS reactive disperse dye structure and non-polar PET component mainly improved colour strength (K/S) values of the dyed PET fabric and W/PET blended fabrics in SC-CO2 compared with those in the aqueous medium. Also, SC-CO2 dyeing has a notable influence on a*, b* and C* values of the dyed PET, N and W/PET fabrics and showed that the uptake of the VS reactive disperse dye and their appearance colors are higher and more saturated than the aqueous dyed samples. The levelling and fastness properties of all dyed fabrics in SC-CO2 medium are similar to those obtained in the aqueous medium. It was observed that VS reactive disperse dye penetrates well into the PET fabric and is chemically bound with the W fabric using both SC-CO2 and aqueous media and did not display significant color difference (∆E) values of W, PET and W/PET fabrics even after 20 washing cycles. The study claims that the VS reactive disperse dye structure and dyed PET-based wool blended fabric are good candidates for industrially SC-CO2 dyeing technology. [ABSTRACT FROM AUTHOR]

In this study, experimental carry out of liquid–vapor and solid–liquid phase transitions were conducted for the ternary system {CO2 (1) + ethanol (2) + acetaminophen (3)} at different concentrations of paracetamol in ethanol for temperatures from 313 to 333 K and pressures up to 12 MPa. Experimental high pressure phase transition data were obtained using the static method in a variable volume view cell. Experimental data were compared with the literature for systems containing acetaminophen in a saturated solution. The presence of paracetamol in the binary system {CO2 (1) + ethanol (2)} significantly alters the behavior of the phase under the conditions of temperature and concentration studied. It was observed that in the ternary system {CO2 (1) + ethanol (2) + acetaminophen (3)} with a saturated solution at the lowest temperature, 313 K, CO2 acts as a cosolvent for mole fractions lower than 0.6. Thermodynamic simulations employing the Perturbed Chain Statistical Associating Fluid Theory (PC-SAFT) Equations of State (EoS) aligned the experimental results adequately. The observed minimal deviations in pressure and temperature validate the efficacy of the thermodynamic models applied in this study. [ABSTRACT FROM AUTHOR]