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Impact cratering is one of the fundamental processes throughout the history of the Solar System. The formation of new impact craters on planetary bodies has been observed with repeat images from orbiting satellites. However, the time gap between images is often large enough to preclude detailed analysis of smaller‐scale features such as secondary impact craters, which are often removed or buried over a short time period. Here we use a seismic event detected on Mars by the NASA InSight mission to investigate secondary cratering at a new impact crater. We strengthen the case that the seismic event that occurred on Sol 1034 (S1034a) is the result of a new impact cratering event. Using the exact timing of this event from InSight, we investigated the resulting new impact crater in orbital image data. The S1034a impact crater is approximately 9 m in diameter but is responsible for over 900 secondary impact events in the form of low albedo spots that are located at distances of up to almost 7 km from the primary crater. We suggest that the low albedo spots formed from relatively low energy ejecta, with individual ejecta block velocities less than 200 m s−1. We estimate that the low albedo spots, the main evidence of secondary impact processes at this new impact event, fade within 200–300 days after formation. Plain Language Summary: On 23 October 2021, the seismometer instrument on the NASA InSight lander detected a seismic event on Mars. The nature of the seismic signal shared characteristics with other events attributed to meteorites impacting the surface of Mars. Reanalysis of images taken by cameras on orbiting spacecraft identified a new impact crater whose location and time of formation matched with the seismic analysis. Our study shows that this 9 m diameter crater has produced over 900 additional, or secondary, impact features up to 7 km away. These secondary features are characterized as being dark spots, often with a tail that points away from the direction of impact, which fade over time. The relatively high number of secondary features from this small impact event is likely due to the low porosity of the rock that was impacted at the surface. We estimate that the dark spots disappear in 200–300 days, thus removing a key set of features used in identifying new impact events on Mars. This timescale places useful limits for future image searches attempting to identify small new impact craters on Mars, and suggests that other such small impact events have been captured in existing data sets and not yet recognized. Key Points: A new 9‐m‐diameter impact crater on Mars identified with in situ seismic and orbital image dataOver 900 low albedo spots identified as a result of secondary ejecta processesSmall impact events have likely been captured in existing data sets and not yet recognized [ABSTRACT FROM AUTHOR]

The nature of the water in hydrated polymer electrolyte membranes (PEMs) is not the same as that of bulk water and affects the rate of diffusion of protons in the material. The traditional methods used in the study of the phenomenon of dielectric saturation assume the presence of a homogeneous or slowly varying external field, conditions that are hard appropriate for (PEMs).

A detailed rheological investigation of a lower critical solution temperature (LCST) blend of deuterated polystyrene-38K/PVME-23K near the critical region is presented. The phase behavior of the blend in the transitional regime was studied by the viscoelastic response of the system during dynamic temperature sweep experiments.

A theoretical study is conducted on the bridge mediated two-electron transfer (TET) in a donor-acceptor (D-A) complex. A type bridge is considered where the intersite coupling in the bridge becomes so large that the TET proceeds along delocalized bridges states but against the background of fast vibrational transitions within and between the states.

Density functional theory (DFT) used the B3LYP method to study the vibrational modes of double six-member ring (D6R) clusters with general composition (M(super n+))x/nH12Si(sub 12-x)Al(sub x)O18 (where x=0.2 and M=H(super +), Na(super +), K(super +), Ca(super 2+), Li(super 2+)).

A study was conducted on the electrodeposition of ZnSe films from dimethyl sulfoxide solutions with a special focus on epitaxial growth. The influence of experimental parameters such as the nature of the substrate, temperature, and hydrodynamic conditions were examined.

A proton NMR spectroscopy was used to determine the detailed structures of the alpha-cyclodextrin complexes. It is shown that a long chain surfactant molecule can bind two alpha-cyclodextrin molecules.

A new type of infrared (IR) optical poling consisting of IR photopumping of appropriate electronic states is studied. It is shown that the relaxation kinetics is consistent with a simple model of electron-phonon anharmonic interactions and the technique may be used in IR optical fibers.

C(sub 60) and C(sub70) molecules are studied in detail. A comparison study indicates that these molecules adsorbed on gold nanoparticles by one of their pentagonal faces gives experimental proof of molecule adsorption on metal surfaces.

The photophysical properties of CdSe nanocrystals arising from the interaction with p-phenylenediamine (PPD) are studied. A surface bound complexation equilibrDium model is proposed.

The structural relationship with single crystalline GaN and the quality of epitaxial Zinc Oxide(ZnO) is studied. It is shown that the in-plane misorientation increases significantly with the dye loading or negative potential.

Most of the surface of Mars is covered with unconsolidated rocky material, known as regolith. High‐fidelity models of the dynamics of impacts in such material are needed to help with the interpretation of seismic signals that are now recorded by SEIS, the seismometer of InSight. We developed a numerical model for impacts on regolith, using the novel Hybrid Optimization Software Suite (HOSS), which is a Lagrangian code mixing finite and discrete element formulations. We use data from hypervelocity impact experiments performed on pumice sand at the NASA Ames Vertical Gun Range to identify and calibrate key model parameters. The model provides insight into the plastic‐elastic transition observed in the data and it also demonstrates that gravity plays a key role in the material response. Waveforms for receivers situated vertically below the impact point are correctly modeled, while more research is needed to explain the shallow receivers' signals. Plain Language Summary: The generation of seismic waves by meteorite impacts in unconsolidated materials, such as Mars regolith, is a complex dynamic process. We present a numerical model based on a novel method and show its potential to explain the main characteristics of shock and seismic waves generated by impacts at laboratory scales. Our goal is to use this model to help with the analysis of data recorded during the InSight mission. Key Points: We conduct a parametric study of a novel Lagrangian numerical model of shock waves in granular media, with application to Mars regolithWe validate this model with a laboratory experiment in pumice sand with an impact velocity of 0.98 km/sAmplitude of shock waves and transition to different regimes is explained by the model for the sensors placed vertically from the impact [ABSTRACT FROM AUTHOR]

Presents a study which considered the low specific resistivity ohmic contact on n-type gallium arsenide (GaAs) as a requirement in the fabrication of high-speed GaAs integrated circuits. Selection of a metallization scheme in annealing; Electrical properties of the ohmic contact; Experimental procedures used.

Abstract The recovery of nitrogen (N) from, and the fertilizer-N value of, low dry-matter (DM) cattle slurry and farm yard manure (FYM), applied annually to perennial ryegrass swards grown at two sites, on sandy loam and shallow calcareous silty clay loam soils, were studied over a 4-year period. Slurry or FYM, applied at target rates of either 150 kg N ha-1 or 300 kg N ha-1 in either October, February or May/June, in combination with 150 kg N ha-1 inorganic fertilizer-N (applied as split dressings before the first and second grass cut), were compared with a set of inorganic fertilizer-N response treatments. DM yield, N offtake, apparent manure-N recovery (in herbage) and manure-N efficiency (compared with inorganic fertilizer-N) were determined at two silage cuts each summer. Soil mineral nitrogen (SMN) measurements in autumn and spring were used to assess potential N leaching loss over winter and to quantify available N residues in the soil in spring. Apparent manure-N recovery and manure-N efficiency were usually greater from slurry applications in February than from those in October, but the timing of the application of FYM had a much smaller effect, compared with the timings of the application of slurry, on the utilization of N from manure by grass. Spring assessment of SMN was useful in quantifying available N residues from October slurry applications. Manure-N recovery for all application timings was, on average, higher from the sandy loam than the shallow calcareous clay loam. The application of slurry to grass in early spring, at a rate of 150 kg total N ha-1 , with the addition of a supplementary 50 kg inorganic fertilizer-N ha-1 , was the most suitable strategy for utilizing slurry-N effectively and for supplying the N requirement for first-cut silage. [ABSTRACT FROM AUTHOR]

The thermal oxidation of silicon is generally modelled by Deal and Grove's theory based on the assumption that the oxygen molecules dissolve in silicon in interstitial positions and migrate to the S1-S1O interface where they react with the silicon substrate Experimental results for oxidation in dry oxygen agree with this theory only for thick oxide films The growth of very thin oxide films exhibits particular features which are discussed in this paper For these films, the growth mechanism is different from that of think films, this difference is possibly associated with the transport of oxygen atoms through the silica network The effect of hydrogenated impurities is also discussed Abstract. [ABSTRACT FROM AUTHOR]

We have studied the structural characteristics of very thin silicon oxide films thermally grown (at 930 °C, 10 Torr) in 18O enriched dry oxygen for times ranging from 0.5 to 22.5 h (corresponding to equivalent thicknesses ranging from 3.2 to 20.8 nm). Chemical etching combined with nuclear microanalysis, x-ray photoelectron spectroscopy (XPS), and reflection high-energy electron diffraction (RHEED) has been applied to the samples. A layer that is very slow to dissolve (of equivalent thickness ∼1.1 nm) was observed for oxide films grown for oxidation times of less than 1 h (equivalent thicknesses under 4.6 nm). As indicated by XPS this layer seems to be related to a structure different from what is observed for thicker films; its existence is also correlated to a structural order as seen by RHEED. [ABSTRACT FROM AUTHOR]