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Cryptotephras in peat and sediment samples are traditionally separated for geochemical characterization using chemical or density floatation techniques following initial tephra identification and shard counting through analysis of ashed residue via light microscopy. However, these practices can be time consuming, subject to practitioner experience and material type, with a potential for sample loss. We present an alternative approach to identify cryptotephra in peat and sedimentary samples, where ashed material is mounted directly in epoxy resin and analysed through back‐scattered electron (BSE) imaging via scanning electron microscopy–energy dispersive X‐ray spectroscopy (SEM‐EDX). Semi‐quantitative, unsupervised chemical maps of epoxy mounts are created within 120 min using 'Feature Analysis' on AZtec software by Oxford Instruments. These maps locate grains of higher atomic mass and categorize phases based on geochemistry. We create a tephra identification method using an ombrotrophic peat sample doped with bimodal Vedde Ash, where recovery of the known tephra proportion in wet peat is 96%. We also propose an automated alternative to optical shard counting, whereby tephra counts identified via Feature Analysis can be ratioed to total grain counts acquired through ImageJ software and extrapolated to the inorganic fraction in wet peat. We apply the method to a minerotrophic peat from Brackloon Wood, Mayo, Ireland, where the Laki ad 1783–84 cryptotephra is successfully identified. [ABSTRACT FROM AUTHOR]

The object of this work is a study of the microstructure and hardness evolution of LPBF-manufactured biomedical alloy Ti-6Al-4V superficially modified by pack carburization and subsequent laser melting. Carburization was conducted in a powder of (NH2)2CO (20 vol. %), K4Fe(CN)6 (20 vol. %), and a carbon black (60 vol. %) at 1000 (C (7 hours). The laser processing was fulfilled by fiber laser «TruFiber 400» (TRUMPF) of 1064 nm wavelength with a power of 400 W and scanning velocity of 5 mm·sec – 1. The investigations included optical (GX71 OLYMPUS) and scanning electron microscopy observations (JSM-7000F JEOL), energy-dispersive X-ray spectroscopy (INCAx-sight, Oxford Instruments), X-ray diffraction (X'Pert PRO, PANalytical, Cu-Kα radiation) and microhardness measurement (LM700AT LECO, under the load of 0.05 kg). It was found that carburization resulted in a 440-700 μm deep carbon-rich layer of (Ti with an upper thin layer comprising TiC, TiO2, and Al2O3. Carburization led to 720 ± 12 HV in a near-surface layer which is two times the bulk structure (322 ± 32 HV). A consequent laser scanning formed a 60-120 (m wide melted layer followed by the heat-affected zone (having a needle-like (Ti-martensite) extended to (∼0.8 mm depth. The melted layer had a fine-grained structure which included the dispersive particles of an oxycarbide Ti(O0.8C0.2) of both grainy and dendrite-like shapes. Consequently, the hardness of the melted layer rose up to 1000-1200 HV with a further gradual decrease, according to the declining carbon content profile. Laser melting was accompanied by cracks and shrinkage cavities formation. It also led to an increased roughness of the surface caused by its boiling under the laser melting. [ABSTRACT FROM AUTHOR]

Two pairs of space-resolved extreme ultraviolet (EUV) spectrometers working at 5–138 Å with different vertical observation ranges of −7 ≤ Z ≤ 19 and −18 ≤ Z ≤ 8 cm have been newly developed to observe the radial profile of impurity line emissions and to study the transport of high-Z impurity ions intrinsically existing in EAST tokamak plasmas. Both spectrometers are equipped with a complementary metal-oxide semiconductor (CMOS) detector (Andor Marana-X 4.2B-6, Oxford Instruments) with sensitive area of 13.3 × 13.3 mm2 and number of pixels equal to 2048 × 2048 (6.5 × 6.5 µm2/pixels). Compared to the currently operating space-resolved EUV spectrometers with a charge-coupled detector (CCD: 1024 × 255 pixels, 26 × 26 µm2) working at 30–520 Å, this spectrometer's performance was substantially improved by using the CMOS detector. First, the spectral resolution measured at full width at half maximum was improved in the whole wavelength range, e.g., Δλ1/2_CMOS = 0.092 Å and Δλ1/2_CCD = 0.124 Å at C VI 33.73 Å and Δλ1/2_CMOS = 0.104 Å and Δλ1/2_CCD = 0.228 Å at Mo XXXI 115.999 Å, thus enabling a more accurate analysis of spectra with complicated structure such as tungsten unresolved transition array in the range 45–65 Å. Second, the temporal resolution was largely improved due to the high-speed data acquisition system of the CMOS detector, e.g., Δt_CMOS = 15 ms/frame and Δt_CCD = 200 ms/frame at routine operation in the radial profile measurement. Third, signal saturation issues that occurred when using the old CCD sensor during impurity accumulation now disappeared entirely using the CMOS detector due to lower exposure time at high readout rates, which largely improved the observation performance in similar impurity burst events. The above-mentioned performance improvements of the space-resolved EUV spectrometer led to a rapid change in the W XXXIII (52.22 Å) radial profile during a single cycle of low-frequency sawtooth oscillation with fst = 5–6 Hz at a sufficient detector count rate. [ABSTRACT FROM AUTHOR]

The carbon nanotubes (CNTs) embedding into metal-matrix composites is accompanied with difficulties in providing their uniform distribution within the matrix. Therefore, choosing a way to add CNTs into a metalmatrix and a general technological route for composite-material fabrication are crucial tasks. This study aims to develop copper–CNT composites by powder-metallurgy methods from composite powders and to analyse the structure and properties of such materials. The composite powders are produced by electrodeposition from the copper-bearing sulfuric acid electrolyte. The CNTs are dispersed in electrolyte, using sonication in the presence of surfactants having the different-type actions. In this research, anionic surfactant sodium lauryl sulphate NaC12H25SO4 (SDS) and cation surfactant cetyltrimethylammonium bromide C19H42BrN (CTAB) are used. Multiwalled CNTs (with outer diameter of 8–28 nm and length of 0.5–10 μm) are prepared by the chemical vapour deposition (CVD) and thermally annealed at temperature of 650C through catalysts Al2O3–Fe2O3–MoO3. The concentration of CNTs in the plating bath is of 0.15 g/l. The electrodeposited copper powder is used as a matrix for sintered samples’ fabrication. Samples for the investigation are compacted at pressure of 400 MPa and sintered at 950 C in a hydrogen atmosphere. The study of sinteredsamples’ structural characteristics is performed, using the scanning electron microscope (Tescan Mira 3 LMU). The local microanalysis of the samples’ elemental composition is made by energy dispersive spectroscopy (EDS) with a radiation detector ‘X-max 80’ (‘Oxford Instruments’, England). The amperemeter and voltmeter method is used for the resistance measurement of sintered samples. After samples’ sintering, the CNTs in the copper matrix are revealed mainly at the grain boundaries and within the pores. The CNTs content increasing (in investigated limits) reduces the electrical resistance of the sintered material. The highest content of CNTs is provided by deposition in the electrolyte with cation surfactant CTAB. The investigation results are helpful for the copper materials’ manufacture for electrical contacts. [ABSTRACT FROM AUTHOR]

We demonstrate successful operation of a continuous flow liquid helium magnetic cryostat (Oxford Instruments, Microstat MO) in closed cycle operation using a modular cryocooling system (ColdEdge Technologies, Stinger). For the system operation, we have developed a custom gas handling manifold and we show that despite the lower cooling power of the cryocooler with respect to the nominal cryostat cooling power requirements, the magnetic cryostat can be operated in a stable manner. We provide the design of the gas handling manifold and a detailed analysis of the system performance in terms of cooling times, magnetic field ramping rates, and vibrations at the sample. Base temperatures can be reached within 10 h while the superconducting magnet can be energized at a ramping rate of 0.5 T/min. Vibrations are measured interferometrically and show amplitudes with a root mean square on the order of 5 nm, permitting the use of the system for sensitive magnetic microscopy experiments. [ABSTRACT FROM AUTHOR]

The purpose of this study is to elucidate the flow features of the dissimilar Al-Cu welded plates. The welding method used is Bobbin Friction Stir Welding (BFSW), and the joint is between two dissimilar materials, aluminium alloy (AA6082-T6) and pure copper. Weld samples were cut from along the weld line, and the cross-sections were polished and observed under an optical microscope (OM). Particular regions of interest were examined under a scanning electron microscope (SEM) and analysed with Energy Dispersive X-ray Spectroscopy (EDS) using the AZtec software from Oxford Instruments. The results and images attained were compared to other similar studies. The reason for fracture was mainly attributed to the welding parameters used; a higher rotational speed may be required to achieve a successful BFSW between these two materials. The impact of welding parameters on the Al-Cu flow bonding and evolution of the intermetallic compounds were identified by studying the interfacial microstructure at the location of the tool action. The work makes an original contribution to identifying the solid-phase hybrid bonding in Al-Cu joints to improve the understanding of the flow behaviours during the BFSW welding process. The microstructural evolution of the dissimilar weld has made it possible to develop a physical model proposed for the flow failure mechanism. [ABSTRACT FROM AUTHOR]

TolTEC is an upcoming millimeter-wave imaging polarimeter designed to fill the focal plane of the 50-m-diameter Large Millimeter Telescope (LMT). Combined with the LMT, TolTEC will offer high-angular-resolution (5 ′ ′ –10 ′ ′ ) simultaneous, polarization-sensitive observations in three wavelength bands: 1.1, 1.4, and 2.0 mm. Additionally, TolTEC will feature mapping speeds greater than 2 deg 2 / mJy 2 / h , thus enabling wider surveys of large-scale structure, galaxy evolution, and star formation. These improvements are only possible through the integration of approximately 7000 low-noise, high-responsivity superconducting Lumped Element Kinetic Inductance Detectors. Utilizing three focal planes of detector arrays requires the design, fabrication, and characterization of a unique, large-scale cryogenic system. Based on thermal models and expected photon loading, the focal planes must have a base operational temperature below 150 mK. To achieve this base temperature, TolTEC utilizes two cryocoolers, a Cryomech pulse tube cooler and an Oxford Instruments dilution refrigerator, to establish four thermal stages: 45 K, 4 K, 1 K, and 100 mK. During the design phase, we developed an object-oriented Python code to model the heat loading on each stage as well as the thermal gradients throughout the system. This model has allowed us to improve thermal gradients in the system as well as locate areas of poor thermal conductivity prior to ending a cooldown. The results of our model versus measurements from our cooldowns will be presented along with a detailed overview of TolTEC's cryogenic system. We anticipate TolTEC to be commissioned at the LMT by Spring 2020. [ABSTRACT FROM AUTHOR]

Oxford Instruments plc has acquired First Light Imaging SAS, a scientific camera specialist based in France. The acquisition will enhance Oxford Instruments' world-class camera offering and expand its customer base. First Light's low-noise scientific cameras for infrared and visible imaging are complementary to Oxford Instruments' existing portfolio. The acquisition will also provide opportunities for both companies to expand into adjacent markets. Under the terms of the acquisition, Oxford Instruments will pay an initial cash consideration of €15.7m, with an additional €3m conditional on First Light's trading performance. [Extracted from the article]

INTRODUCTION: Tissue engineering strives for innovative solutions in addressing challenges associated with contemporary bone tissue implants. This study focuses on the electrophoretic deposition (EPD) of hydroxyapatite-based bioceramic composites containing antibacterial agents onto titanium surfaces. Two composite coatings, hydroxyapatite/chitosan (HAP/CS) and hydroxyapatite/chitosan/gentamicin (HAP/CS/Gent) were developed to combat issues such as poor adhesion, limited antibacterial potential, limited bioactivity, and potential toxicity of implant materials. EXPERIMENTAL: EPD was performed at constant voltage (5 V, 12 min) on pure Ti plates from aqueous (HAP/CS and HAP/CS/Gent) suspensions. The uniformity and functionality of the deposited coatings were assessed through comprehensive physico-chemical characterization using X-ray diffraction (XRD) (Philips PW 1710, Netherlands) and scanning electron microscopy (SEM, Hitachi S-4700, J) equipped with energy dispersive X-Ray spectroscopy (EDS, X-Max, Oxford Instruments, UK). Antibacterial activity was evaluated against Staphylococcus aureus TL and Escherichia coli ATCC 25922 by quantitatively monitoring changes in the viable number of bacterial cells in suspension. Cytotoxicity against MRC-5 and L929 cell lines was investigated using trypan blue dye-exclusion test (DET) and MTT assay for assessing cell metabolic activity. Statistical significance was determined for antibacterial and cytotoxicity results by one-way analysis of variance (ANOVA), followed by multiple comparisons post-hoc test. RESULTS AND DISCUSSION: XRD revealed broadened diffraction maximums corresponding to fine HAP crystallites. Porous surface with homogeneously distributed spherical HAP agglomerates embedded in wax-like polymers' matrix of CS was observed for both coatings by SEM. The addition of gentamicin significantly enhanced the antibacterial activity of the HAP/CS/Gent coating – complete reduction of S. aureus bacterial cells was achieved within 1 h of exposure. MTT and DET tests indicated low cytotoxicity against MRC-5 and L929 tested cell line for both samples. Slightly decreased cell percentage viability due to gentamicin presence was observed for HAP/CS/Gent. CONCLUSIONS: Single-step EPD yielded antibacterial composite coatings with potential for biomedical applications. HAP/CS/Gent showed successful gentamicin loading, favorable crystalline structure, and strong antibacterial effects. The presence of fine HAP crystallites yielded a larger surface area, favorable for new bone growth and improved osseointegration. HAP/CS/Gent exhibited good antibacterial activity against both tested bacteria (especially pronounced against S. aureus – bactericidal effect), while preserving low cytotoxicity, indicating the high potential for biomedical applications. [ABSTRACT FROM AUTHOR]

This document provides information on three different products related to cryogenics, vacuum equipment, materials, and semiconductors. The first product is a customizable diaphragm gas pump from KNF that offers precise vacuum control for various applications. The second product is a compact dilution refrigerator called ProteoxS, which is designed for low-temperature physics and is suitable for research, photonics, and sensing applications. The third product is an epoxy called Supreme 3DM-85, which serves as a damming compound in encapsulation applications and is designed for heat-sensitive components. These products are manufactured by KNF Neuberger Inc, Oxford Instruments NanoScience, and Master Bond Inc, respectively. [Extracted from the article]

The article evaluates several physics equipment including the VCP Pirani vacuum transducer from Thyracont Vacuum Instruments GmbH, the scanning ion-conductance microscopy (SICM) module from Park Systems Inc., and the X-Max Extreme silicon drift detector from Oxford Instruments Plc.

The article offers brief information on several microscopy equipment and supplies including the NanoZoomer SQ slide scanner from Hamamatsu Photonics, the Labelmark 6 Label Design software from Brady, and the AZtecFeature particle analysis platform from Oxford Instruments.

The article features several scientific instruments, including the StingRay structured light-generating laser from Coherent, the Cryofree Optistat Dry optical cryostat from Oxford Instruments and the FLEX ultraviolet/visible/near-infrared microspectrophotometer from CRAIC Technologies.

Introduction: More than 5,200 tons of extraterrestrial material (12-700 mkm) fall out to the Earth each year [1]. A fraction of this dust that hits the ground could be collected at the Earth's surface in the form of microscopic particles (<2 mm) called micrometeorites. The most common archives of micrometeorites are deep-sea sediments, snow, ice, and sediments in polar areas [2]. Antarctica and its ice cover is a unique place for collecting micrometeorites and cosmic dust, due to the absence of terrestrial and industrial dust. The study of extraterrestrial matter is of considerable importance because they are the best-preserved materials of the early Solar System available [3]. Samples and Methods: In this work, we present investigations of two types of samples. The first is the collection of magnetic micrometeorites on a small neodymium magnet (30 x 20 x 10 mm) in a string exposed on a triangle that stands 4.6 km from station Vostok for one year. Magnets were wrapped into the tape to prevent gluing samples to the magnet. The second is the samples of blue ice originating from different horizons near the Voltat massif and Lomonosov mountains. Magnetic fractions (nanoscale cosmic dust) from melted ice were removed by using a permanent magnet. The morphology and elemental composition of magnetic separates were studied using scanning electron microscopy "Merlin" ?arl Zeiss equipped with an energy-dispersive spectrometer "Aztec X-Max" Oxford Instruments. Surface morphology was investigated at an accelerating voltage of 5 keV on SE mode (secondary electrons). Elemental analysis and surface mapping were carried out at an accelerating voltage of 20 keV with AsB mode. Results: Microscopic investigations showed widespread micrometeorites in all studied samples. Magnetic particles collected on magnets represented micrometeorites, mostly spherules, curved fragments, and magnets themselves. Analysis of particles showed that particles were presented mostly by iron oxides, with a low content of other elements (Mg, Si, Cr, Ca, etc.). Particles containing Nd, Fe, Dy were originating from the magnet itself. For future work, the tape should be changed to another material to prevent contamination by the magnet itself which is resolved now in ongoing expositions using the same type of magnets but covered with Teflon (Loctite LB 8192). The chemical analysis of nanosized dust from the ice showed chromic iron which could justify the background magnetic component of the cosmic dust. Nanoparticles in the form of spherules were not observed. Acknowledgment: The reported study was funded by RFBR and DFG according to the research project ? 20-55-12006, and the Ministry of Education and Science of the Russian Federation (The projects FEUZ-2020-0059). [ABSTRACT FROM AUTHOR]

Introduction: Enstatite chondrites (ECs) are thought to represent the material present in the accretion regions of the terrestrial planets [1]. However, ECs contain unique mineral assemblages which indicate that they formed under much more reduced conditions than Earth. It has long been assumed that ECs formed from material condensed at supersolar C/O ratios, however, recent trace element work suggests that ECs may instead be derived from precursors that formed in a more oxidising environment [2]. Later processing of these precursors in an unusually S (and other volatile)-rich and O-poor environment may then explain the highly reduced nature of ECs [2, 3]. We are analysing relict grains to test the hypothesis of an evolving nebular composition recorded in unequilibrated ECs. Relict forsterite grains did not crystallise in-situ with their host melt [4], instead forming by reduction of a more FeO-rich olivine, either before or during the formation of the host chondrule [5, 6, 7]. Relict grains in some ordinary and carbonaceous chondrites have been observed to have a "dusty" texture [4, 5, 8, 9, 10]; dusty grains contain micronsized blebs of essentially Ni-free metal. Isolated dusty forsterite grains have been observed to exhibit blue cathodoluminescence (CL) [11] in disequilibrium with their host chondrule, therefore suggesting a relict origin. Forsterite grains with red-CL cores and blue-CL rims suggest relict cores that have been equilibrated at lower temperatures before chondrule formation [8] with an overgrowth of a chondrule melt enriched in trace elements [12]. The cores of these grains may or may not have a dusty texture but are assumed to have a similar formation process [4], suggesting that most forsterite grains within type I porphyritic olivine-pyroxene (POP) chondrules could be considered relict grains [13]. Method: Polished sections of Dominion Range 14021 (EH3; section #11) and Larkman Nunatak 12156 (EH3; section #6) were studied using a ZEISS Evo 15LS SEM. Large area elemental mapping was carried out with an Oxford Instruments Aztec EDS system to locate olivine grains. High-resolution cathodoluminescence (CL) imaging has been performed with a Gatan ChromaCL system, at 10kV accelerating voltage, 3nA beam current and at a distance of ~1 mm from the CL detector. Findings: Forsterite grains were identified and imaged in 37 chondrules in DOM 14021,11 and 28 chondrules in LAR 12156,6 (~20% / ~25% of chondrules in the samples respectively); forsterite was found to occur as anhedral to subhedral grains poikilitically enclosed in enstatite. Forsterite abundance within the chondrules ranged from ~2% to ~30% for DOM 14021,11 and from ~2% to ~15% for LAR 12156,6. The largest forsterite grain in each sample measured ~0.2×0.2 mm and ~0.26×0.33 mm respectively. Based on the size and morphology of their forsterite grains, 22 POP chondrules in DOM 14021,11 and 9 POP chondrules in LAR 12156,6 were further imaged using the CL detector. All chondrules analysed are type I, FeO-poor with Fo(>98.7); 1 chondrule in DOM 14021,11 (~30% forsterite) is more ferroan with Fo96.55. Red and blue CL observed in the chondrules of both samples indicate varying concentrations of trace elements in the forsterite grains. Isolated dusty forsterite grains exhibiting blue CL and grains exhibiting red-CL cores surrounded by blue-CL rims were identified in both samples. Implications: Several isolated dusty forsterite grains in DOM 14021,11 and LAR 12156,6 exhibit blue CL, in disequilibrium with their host chondrule and suggesting a relict origin [11]. Forsterite grains with red-CL cores surrounded by blue-CL rims were also identified, indicative of relict cores with an overgrowth of a chondrule melt enriched in trace elements [12]. Our work will advance to the analysis of trace element concentrations and oxygen isotopic variations of the relict grains. This analysis will provide further understanding of the origin and history of relict grains and subsequently the evolving composition of the EC formation region. [ABSTRACT FROM AUTHOR]

Introduction: Iron meteorites have a unique structure formed in equilibrium processes. This makes it possible to use them as iron-nickel substrates for the synthesis of carbon nanotubes (CNTs) [1]. In this case, the meteorite acts both as a substrate and as a catalyst. There are several questions related to the influence of the substrate/catalyst on the growth of CNTs. For example, does catalysis take place at the atomic or cluster level [2]? This research is devoted to mechanisms of CNTs obtaining on the meteorite's surface. We used the Chinga ataxite (ungrouped iron). It contains the submicroscopic duplex plessite and kamacite spindles with enveloping taenite [3]. Previously [4], we have already described the results of the synthesis; it was noted that, in parallel with the growth of CNTs, the formation of hematite nanowires took place. For comparison, two samples of an iron-nickel-cobalt alloy (FNC20) containing 20 wt.% nickel and about 1 wt.% cobalt was used. To determine the effect of oxidation, one of the samples was thermally oxidized. Materials and Methods: The FNC20-1 and FNC20-2 samples are examples of a single-phase alloy obtained from Fe, Ni, and Co metal powders at a temperature of 1700°C. The average grain size was about 1 µm. The samples of Chinga meteorite and FNC20-1, FNC20-2 were prepared using standard metallographic polishing and etching with 1 wt. % nital during 5 minutes. This led to the revealing of a submicron structure of the Chinga sample. Then several areas were marked on the samples and were analyzed before and after the synthesis of nanomaterials. The nanomaterials on the Chinga meteorite and FNC20-1 were synthesized by a catalytic pyrolysis of ethanol using "CVDomna" commercial equipment for carbon nanotube growth. The samples was placed into a reaction chamber, then heated to 600°C at a pressure of 1 kPa. A vapor-gas mixture of ethanol and air was passed into the reaction chamber during 10 minutes at a linear increase in pressure to 15 kPa, then they were cooled to 400°C at a pressure of 1 kPa and then cooled under an ambient air. At first the FNC20-2 was oxidized at a temperature of 600°C and an air pressure of 15 kPa for 10 minutes, then it was observed with SEM. After that, the synthesis of nanomaterials was carried out on it as described above. The samples were studied with ZEISS Axiovert 40 MAT optical microscope before the synthesis and by scanning electron microscopy and energy-dispersive X-ray spectroscopy using Zeiss Sigma VP equipped with X-max detector by Oxford Instruments before and after the synthesis. Results: We have found synthesized CNTs on the plessite surface of Chinga sample. The average diameters of CNTs were 20 nm. This is described in more detail in [4]. The average Ni content of plessite in the Chinga is above 16 wt.%, the Ni content of taenite is ~ 25 wt.%. Therefore, we used an alloy with 20 wt.% Ni to test whether the content of the element affects the growth of CNTs. As a result of synthesis, amorphous forms of carbon were found on the surface of the FNC20-1 sample. The surface of the FNC20-2 surface after the oxidation was covered with oxide film and hematite nanorods on top layer of the film. The diameters of the nanorods were ~ 30 nm and the lenths were ~ 1-2 µm. In some places, the film is cracked and peeled off with flakes. The surface under the flakes contained pits with the diameters 50-100 nm. After the synthesis of the nanomaterials some remaining hematite nanorods were found. In places where the oxide film came off in flakes, the surface after synthesis was different. It was covered with amorphous carbon, and rare CNTs with an average diameter of about 25 nm were found. As mention in [5] with an excess of catalyst, excessive release of soot begins, which leads to contamination of the CNTs. Thus, more CNTs could be found under the amorphous layers. Discussion: We carried out experiments with two-phase plessite of Chinga meteorite and one-phase 20 wt.% Ni alloy. A precence of the CNTs on the meteoritic plessite and an absence of the CNTs on the meteoritic taenite, kamacite and one-phase artificial alloy showed that Ni content did not affect on the synthesis. Deeper etching led to a higher yield of CNTs on the sample Chinga [4]. Thus, we can conclude that the entire particle participates in the precursor gas catalysis, and when we provide comprehensive gas access to it through deep oxidation, the yield of CNTs is greater. On the other hand, oxidation of one-phase alloy has changed its surface. There we had hematite nanorods and heat theatment pits under the peeled flakes. Authors of [6] showed that the oxidation reduces the surface tension coefficient, which improves the saturation of the metal catalyst with carbon. So even non-catalytic materials provide the CNTs growth. According to the [1, 5] and the experiments carried out we can propose the CNTs synthesis mechanism. The precursor gas (CO) gained access to individual high-nickel plessite particles, then Fe-Ni particles were saturated with C and it is excreted as a precipitate. In this case, the Fe-Ni particle remains on the substrate, and the end of the CNT goes up from it. The driving force of the process is the concentration gradient in the metal particle. [ABSTRACT FROM AUTHOR]

Introduction: Sediments of Lake Bannoe where studied for detection extraterrestrial matter. Bannoe (53°35'48.13"N 58°37'47.28"E) is located in the Southern Urals, Russia. Length of investigated core 5.06 meters and according the radiocarbon dating the lake is ~12.5 thousand years of age. Seismoacoustic investigations shows that sediments are stratified and not distracted at the sampling point. Previous studies [1, 2, 3, 4] shows that micrometeorites and cosmic dust can be found in different types of sediments and rocks and that magnetic properties can be used for choosing reliable samples for further investigations Thermomagnetic measurements were carried out for all samples of the core. Six of them which is showing presence of iron-nickel alloys (Curie temperature higher that 690 °C) and in some cases magnetite (Curie temperature ~580 °C) were chosen for magnetic separation and further investigations. Methods: Differential thermomagnetic analysis was carried out for tracing magnetic minerals according to their Curie temperature. Temperature dependences of induced magnetization up to 800°C at a heating rate of 100°C per minute in a constant magnetic field of 0.4 T were obtained. The curves of the first and second heating allow to evaluate possible mineralogical transformations in a sample. The morphology and elemental composition of magnetic separates studied using scanning electron microscopy "Merlin" ?arl Zeiss equipped with an energy-dispersive spectrometer "Aztec X-Max" Oxford Instruments. Surface morphology was investigated at an accelerating voltage of 5 keV on SE mode (secondary electrons). Elemental analysis was carried out at an accelerating voltage of 20 keV with AsB mode. Results: According to the thermomagnetic analysis samples with Fe-Ni alloys distributed along the core nonuniformly and detected in 48 samples out of 250. The largest number of samples with iron-nickel alloys was found in sediments aged 6200, 8800 and 12000 years ago. Microscopic investigations showed presence of micrometeorites in studied samples. Shape of particles from round to egg-shape. Size of particles varies from 5 to 30 microns. Almost all microparticles have specific wavy surface. Finding differences in extraterrestrial matter in time would be helpful for understanding changes in the type of material falling to the Earth's surface. This study was funded by the grant of the President of the Russian Federation for state support of young Russian scientists - candidates of sciences ? MK-4100.2021.1.5. [ABSTRACT FROM AUTHOR]

Introduction: The study of martian meteorites has provided a deeper understanding of volcanism on Mars. The small number of samples analyzed have begun to answer large-scale questions pertaining to the geological history of the martian surface. Here, we investigate a basaltic shergottite meteorite from the early Amazonian [1] - one of only two currently known martian meteorites that crystallized at this time [1,2]. Shergottites sample a suite of different lithologies, formation ages, ejection ages and volcanic settings [3], therefore careful consideration of each sub-type is critical to building a wider understanding of martian volcanism as a function of both formation age and location. North-West Africa (NWA) 8159 is the only shergottite classified as an augite basalt [1, 4]. It likely crystallized from an evolved melt at 2.37 ± 0.25 Ga based on Sm-Nd analyses [1], which is much older than the majority of the shergottite group (typically <600 Ma in formation age) [1]. We investigate the crystallization conditions of this early Amazonian rock, and what implications that has for the environment in which it formed. The aim of this initial crystallographic examination is to qualify and quantify any crystallographic textures. These may be used as an indicator for emplacement of the rock, for example in a fast-moving flow or in a cumulate setting. We will also investigate any shock-induced micro- and nano-structures within apatites as an indicator of conditions during impact, and comparisons between apatite grains proximal and distal to the melt vein will also be conducted. Methods & Materials: A 1-inch round epoxy thick section of NWA 8159 (supplied by UNM) was polished for 4 hours using a Vibromet polisher with colloidal silica solution to obtain a reflective surface, and subsequently coated with a ~5 nm carbon coat. Backscatter electron (BSE) and energy dispersive spectrometry (EDS) images were collected at 20 KeV accelerating voltage on the TESCAN TIMA scanning electron microscope (SEM) at the John de Laeter centre (JDLC) at Curtin University. All crystallographic information was then collected using the electron backscatter diffraction (EBSD) on the TESCAN MIRA3 SEM using Oxford Instruments' Symmetry CMOS detector. Large area maps were created based on crystallographic information obtained at a step size of 1 micrometre. Data were processed using AZtecCrystal software, and noise reduction was performed as per common protocol [e.g. 5, 6]. Grains were identified based on a 10° misorientation threshold. Phase, crystallographic orientation and crystal-plastic deformation maps were collected or deduced based on Kikuchi bands recorded by the detector. Results: Preliminary results from earlier large-area mapping demonstrates that much of the sample is crystalline with very little amorphous material present as discovered in prior studies [e.g. 8]. Mineralogy of the large area map is broken down as follows; clinopyroxene 48%; plagioclase feldspar 36%; magnetite 8%; olivine 3%; ~5% attributed to the Ca-rich veins, and other minor phases such as apatite [9]. Crystallographic analysis of this data showed a weak alignment of the <010> axis across the plagioclase grains, whereby the orientation of this axis formed a weak cluster. This axis is typically the shortest crystallographic axis in plagioclase. There is no alignment of the other two axis. Apatites are present across the surface of the exposed sample, and will be further investigated prior to the meeting. Discussion: The presence of an alignment in the <010> axis indicates that a consistent force was applied during the final phase of crystallization of this rock. The lack of alignment in the other two axes suggest this texture was not formed by flow (as in [7]), but rather by a compressive force, such as gravity or impact, whereby the shortest axis of the grains will stack parallel to the direction of the force being applied (e.g. [5]). The limited amount of maskelynite within this sample would indicate this was aligned during crystallization and is therefore interpreted as a gravitational settling texture. This is in agreement with earlier studies, where the groundmass was used to infer a surface lava flow, or shallow sill origin as we find here. Conclusions and further work: The crystallographic alignment of the plagioclase grains examined thus far indicate a settling texture is present. We aim to examine crystallographic properties not only of the plagioclase laths, but also the fine-grained groundmass ahead of the meeting. We will also investigate the apatites across the sample using EBSD and atom probe techniques to compliment the EBSD analyses already performed. [ABSTRACT FROM AUTHOR]

Introduction: Hypervelocity impacts induce extreme pressures and temperatures that are not normally produced by endogenic geological processes. Features created in response to these conditions can thus be used to infer the occurrence of a bolide impact and confirm a suspected impact structure (planar deformation features, PDFs, in quartz are perhaps the best known of these [1]). The mineral zircon (ZrSiO4) responds to extreme pressure-temperature (P-T) conditions in a variety of crystallographically controlled ways [2]. Given the use of zircon in studies of shock metamorphism, it is critical to understand which features in zircon are unique to hypervelocity impacts and which may form as a result of other extreme P-T excursions, such as lightning strikes. Additionally, analysis of deformation and phase transitions in zircon may shed light on the P-T conditions of such events. Previous studies of fulgurites (tubular bodies of glass and fused clasts that form in response to lightning) have noted zircon with rims of ZrO2 [3,4] and one study documented a Zr-rich patch of glass interpreted to represent a melted zircon grain [4]. With the aim to recognize features that form in response to extreme P-T excursions but are not unique to hypervelocity impacts, and to understand better the P-T conditions of these events, we undertook imaging and microstructural analysis of zircon and baddeleyite (monoclinic ZrO2) in a recently formed fulgurite. As an experimental control, we also imaged zircon from nearby soil and rock that was not exposed to the lightning strike. Samples: The fulgurite sample studied here formed as lightning struck vegetated soil in York County, Pennsylvania, USA, in 2004. The rock control sample collected near the fulgurite is a phyllite, consistent with local bedrock being mapped as metasedimentary rocks of the late Proterozoic or early Cambrian Harpers Formation [5]. The soil control sample contains mm-scale clasts of phyllite, supporting a local provenance. Methods: A portion of the fulgurite was mounted in epoxy and cut perpendicular to it exterior wall. This exposed an approximately circular cross-section 20 mm in diameter, which was polished with diamond suspension and colloidal silica. Imaging and microstructural characterization of zircon and baddeleyite by electron backscatter diffraction analysis were performed on an FEI Quanta FEG 650 scanning electron microscope. Microstructural data were processed in Oxford Instruments Channel 5 software and further data analysis was done in ARPGE software [6]. Results: Zircon grains from the control samples displayed a range of features, including xenotime rims and porosity. However, none displayed rims or inclusions of baddeleyite. Of the 91 Zr-rich grains identified in the fulgurite, five are composed entirely of vermicular baddeleyite. The other 86 are zircon grains, with 19 of these displaying granular baddeleyite and 29 having rims of vermicular baddeleyite. The abundance of baddeleyite in the zircon grains decreases with increasing distance from the fulgurite's central void, indicating that the baddeleyite formed in response to the lightning strike. Microstructural analysis of a rim of vermicular ZrO2 on a zircon grain revealed that it is composed of systematically oriented clusters of baddeleyite, consistent with cubic to monoclinic transformation and the former presence of cubic ZrO2 in the sample [7]. Cubic ZrO2 is a high-temperature phase (forming at T>2370°C at low pressure) and previously documented natural occurrences were associated with hypervelocity impacts [8-10]. Implications: Evidence for precursor cubic ZrO2 in baddeleyite rims on zircon grains in a fulgurite indicate that cubic ZrO2 - despite indicating extreme P-T conditions - is not unique to, or diagnostic of, hypervelocity impacts. Furthermore, the observation adds new constraints to the P-T conditions of lightning strikes. Comprehensive results and discussion are presented in [11]. Acknowledgments: This project received funding from the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Individual Fellowship Grant Agreement No. 792030, supporting Kenny. We thank Cyril Cayron for helpful discussions and support with ARPGE software. [ABSTRACT FROM AUTHOR]

Introduction: During preparations for Martian exploration it is important to test the design and functionality of a spacecraft's components with materials that are similar to what they will encounter using terrestrial analogue samples [1], ensuring mission objectives can be met effectively [1]. Geological terrestrial analogue samples focus on the petrological and geochemical similarity of these terrestrial rocks to Mars [1], and are useful for Martian exploration preparations owing to the current absence of directly returned samples from Mars' surface [1,2]. Through satellite imagery, abundant basaltic lava has been observed on the Martian surface [3,4], the morphology of which has been previously likened to terrestrial flood lavas [5,6]. These observations, and a lack of plate tectonics on Mars indicate that regions of terrestrial intraplate volcanism are potential targets for finding accurate analogue samples for Martian volcanism [7]. Here, we present a new terrestrial analogue that best matches petrologically and geochemically to the abundant Martian shergottite meteorites, and may provide a further testbed for Martian exploration technology. Methodology: Four terrestrial intraplate basalts similar in origin to Martian volcanism were selected; two Hawaiian basalts (H-001 & H-002), a European Space Agency (ESA) analogue from the ESA²C collection (ESA01- A), and a sample from an intra-rift setting in New Mexico (NM-001). These were compared to Martian meteorites representative of Mars' geochemistry and petrology (North West Africa (NWA) 7397, NWA 1110 and Tissint). All samples were mounted and carbon coated prior to analysis. Petrological and geochemical analyses were carried out using non-destructive scanning electron microscopy (SEM-EDS). Data were collected using the JEOL 7001F SEM within Plymouth Electron Microscopy at 20kV coupled with an Oxford Instruments 50 mm² X-Max detector and Oxford Instruments AZtec (V6.0) software, collecting point EDS data and element maps for each sample. Results and Discussion: H-001 and ESA01-A were both tholeiitic in composition and more similar to the Martian shergottites than the calc-alkaline compositions exhibited by H-002 and NM-001. Petrographically speaking, olivine compositions across the Martian meteorites were similar to their terrestrial counterparts. Olivine in ESA01-A was the most Ferich (Fa45) and demonstrated the greatest similarity to NWA 7397 (Fa41), whilst in the remaining terrestrial samples olivine was Mg-rich (Fa22-30) and more analogous to antecrysts in olivine-phyric shergottites (Fa30-34). ESA01-A exhibited extensive plagioclase zoning that is not observed in the Martian shergottites analyzed. High-Ca pyroxene compositions across H-001 (Ens49Fs15Wo37), and range of low-Ca to high-Ca pyroxene compositions in NM-001 (Ens20Fs36Wo44 average) were similar to the Martian shergottites (Ens32-53Fs17-35Wo14-51), but neither were a perfect match. None of the terrestrial samples in this study were identical to the Martian shergottites analyzed [8]. With that said however the official terrestrial analogue, ESA01-A, demonstrated the poorest similarity to the Martian shergottites analyzed whereas the intra-rift basalt, NM-001, was petrographically the most similar to Martian shergottites in this study, particularly to olivine-phyric shergottites NWA 1110 and Tissint. The texture of these samples can be seen in Figure 1. Full results will be presented at the meeting. [ABSTRACT FROM AUTHOR]