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Remnant extraterrestrial chrome spinels from terrestrial sediments provide information on how the mixture of meteoritic materials falling to Earth has changed over Earth’s history. The parent meteorite type of each grain can be identified by characteristic elemental and oxygen-isotope abundances. Some meteorite types can be difficult to classify because their chrome-spinel compositional ranges overlap. Silicate inclusions within chrome spinels of modern ordinary chondrites have been shown to have discriminating power among meteorite subclasses. We employed energy-dispersive X-ray spectroscopy in a scanning electron microscope (SEM) and in a (scanning) transmission electron microscope (S/TEM) to investigate inclusions in chrome-spinel grains from Ordovician and Jurassic sediments. Unaltered Ordovician inclusions allowed us to establish the size limits for reliable SEM analysis of inclusions. The Jurassic grains were more altered, but the use of STEM techniques on small inclusions (

Final properties of unfired earth are influenced by composition of earth mixtures. Methylene blue test could be useful method for analysis of earth composition. This would facilitate of designing unfired earth building structures because composition of natural earth is various. Principle of methylene blue test is measure of amount of adsorbed methylene blue dye by clay. The essential component of earth mixtures is clay because clay fulfils a function of binder. Experimental measure of adsorption capacity of individual kind of clay is described in this paper. Adsorption capacity was investigated in montmorillonite, kaolinite, illite-kaolinite and illite clays. The obtained results show that the adsorption capacity of clays is significantly different.

Seepage of irrigation water from earth canals is one of the most significant causes of water loss. It should be carefully studied and controlled. This research aims to study the effect of the presence of an impervious layer under the bed of trapezoidal earth canals on the amount of seepage discharge. The finite element numerical model SEEP2D is used in the study. Different scenarios for the canal's dimensions and side slopes are considered. Various values for the vertical distance between the canal's bed and the impervious layer are also studied. The numerical model's results are verified using Vedernikov's equations. The results show that the presence of an impervious layer can reduce the amount of seepage discharge by up to 82.7% compared to that calculated without it, depending on the depth of the pervious layer, the ratio between canal's bed width to water depth, and the side slopes. It is recommended to have boreholes at canal construction sites in order to investigate if an impervious layer exists under the canal's bed. This helps to estimate the correct amount of seepage discharge based on the vertical distance from the canal's bed to the impervious layer under it. Design charts are also provided. Highlights Evaluates the effect of impervious layer under canals’ bed on seepage discharge.; Simulates seepage from earth canals using SEEP2D numerical model.

Photo-oxidation of aqueous Fe(II) (Fe2+ and FeOH+) to Fe(III) (Fe3+) was likely involved in the formation of iron oxide deposits on early Mars and Earth. Previous studies have reported the photo-oxidation reaction rate (i.e., quantum yield, φ = the number of oxidized ferrous ions divided by the number of photons absorbed by ferrous ions) under acidic conditions (pH 0.4–3.0). However, the quantum yield has not been systematically investigated using chemical actinometry in the range of weakly acidic to neutral pH, where the photo-oxidation would have occurred on early Mars and Earth. We report quantum yields for the photo-oxidation of aqueous Fe(II) species over a pH range of 0.5–7.6 with Hg and Xe lamps (with and without optical filters) based on measured Fe(II) concentrations and photon fluxes. The quantum yield under continuous UV and visible light (>200 nm, Xe lamp) varies with pH: φ = 0.103 (±0.005) + 2.17 (±0.27) × [H+]0.5 at pH = 3.0–7.0. Our quantum yield is a few times higher than those reported by the previous studies that used a Hg lamp, indicating the wavelength dependence of the quantum yield. At higher pH (7.1–7.6), with a UV cutoff at ≤ 300 nm (filtered Xe lamp), photo-oxidation of Fe(II) is attributed to oxidation of FeOH+, with a quantum yield of 0.08 ± 0.01. Based on these quantum yields, we estimated Fe(III) (hydro)oxide precipitation rates in the early Gale lakes on Mars, and in Archean oceans on Earth. Results suggest that photo-oxidation may account for the amounts of Fe(III) (hydro)oxides in Gale sediments, assuming aqueous Fe(II) was supplied to the lakes through upwelling groundwater. Photo-oxidation of Fe(II) in Archean oceans on Earth could have been several times more intense than previously thought.

This paper analyzes measurement data on the ionic composition of the upper atmosphere at altitudes of 810–830 km in the period from 2009 to 2018; the measurements were made with RIMS mass spectrometers onboard the space vehicles Meteor-M no. 1 and Meteor-M no. 2. The spatial–temporal variability of the O+ concentration is analyzed in view of the solar activity (Wolf numbers) during a reversal of the solar magnetic field. It is found that the Sun’s magnetic field reversal occurred during the solar maximum of the 24th solar cycle and was accompanied with a significant increase in the concentration of O+.

Using the results of continuous long-term observations over 50 years (including solar cycles 20–24), we study the relationship between Earth’s seismicity and solar activity. An increase in the number of strong earthquakes on the planet occurs during the decline phase of solar activity when charged particle fluxes from high-latitude coronal holes increase, as well as during solar minimum when the intensity of galactic cosmic rays reaches a maximum. The change in the number of strong earthquakes (with magnitude 6) is considered in terms of variations in the intensity of galactic cosmic rays, Forbush decreases, and ground level enhancements in solar cosmic rays (GLE events). The number of strong earthquakes is shown to increase after Forbush decreases with a time lag from ~1 to ~6 days depending on the amplitude of Forbush decrease and after GLE events the number of strong earthquakes increases by ~8 day. In the number of strong earthquakes, a six-month variation is observed, which seems to follow the six-month variation in cosmic rays with a delay of ~1–2 months. It is surmised that the relationship between solar activity and Earth’s seismicity seems to be mediated through the modulation of galactic cosmic rays and atmospheric processes that provoke the occurrence of earthquakes in regions where the situation has already been prepared by tectonic activity.

Nanosilica was prepared from sugarcane bagasse ash (SCBA) and used as additive to the diatomaceous earth (DE). Nanosilica was characterized using laser light scattering (LS), scanning electron micr...

Simultaneous use of data repeated levelling measurements and continuous GNSS observations allows increasing the spatial resolution of geodynamics models. For this purpose, it is necessary to create a single network, a so-called hybrid network. This paper aims at examining the possibility of using scale-free network theory to determine the most relevant common points in hybrid networks using the distance criterion. Used on European network points: UELN (United European Levelling Network) and EPN (European Permanent GPS Network) and the regional network. In the hybrid network (UELN + EPN), 18 pseudo-nodal points with the highest number of links were identified. The accepted distance criterion shows that about 90 % of the EPN points can be used as common points. The application of the scale-free network theory allows determining the significance of points in a hybrid network.

The dynamic analysis and motion control of a spinning tether system for an interplanetary mission to Mars is considered. The space system consists of two spacecraft connected by a tether with thrusts to control its movement. The movements of the tether system in the sphere of action of the Earth, on the interplanetary trajectory and in the sphere of action of Mars are consistently analyzed. In near-Earth orbit, the transfer of the system into rotation with the help of jet engines installed on the end spacecrafts is considered. The spin of the system is used to create artificial gravity during the interplanetary flight. The tether system spins in the plane perpendicular to the plane of the orbital motion of the center of mass of the system. To describe spatial motion of the system, a mathematical model is used, in which the tether is represented as a set of material points with viscoelastic unilateral mechanical connections. When calculating the movement of the system, an approach based on the method of spheres of action is used. Spacecrafts are considered as material points. The level of gravity and spin of tether system is controlled by thrusters. The structure of the controller for controlling the angular speed of rotation of the tether system is proposed. The simulation results are presented to confirm the effectiveness of the proposed control algorithm, which provides a given level of artificial gravity for th e interplanetary mission under consideration.

Silicon, the second most abundant element on earth, has been an ideal candidate for semiconductor industry. Recently, it was shown that a superconducting phase with a large critical temperature Tc ...

In this paper, a seven-parameter BRDF model with double-peak characteristic, which could fit double-peak data, was adopted to fit the BRDF of Mars simulation soil. At the same time, the three-dimensional figure of the original data of the sample and the three-dimensional curve of the fitted curve were given. The results proved that the model worked well for this type of data. In addition, the experimental data of four kinds of earth sand samples with different roughness were also fitted and analyzed. It was found that the model still had a good fitting effect on such data. At last, the Mars simulation soil and the four kinds of earth sand samples with different roughness were compared horizontally and vertically. Moreover, the double-peak characteristics and other properties of the Mars simulation soil and the earth sand were analyzed under the same and different roughness.

The three-dimensional geoelectrical model of the Earth’s crust and upper mantle of the Crimean region and adjacent territories has been built for the first time. It is based on the results of the Earth’s low-frequency electromagnetic field experimental observations, conducted in 2008—2013 by the Institutes of the National Academy of Sciences of Ukraine. The subvertical conductive zones or contacts of the different resistivity mainly in the near-surface layers coincide with the fault structures, most of which are confined to the boundaries between the different tectonic elements, such as the Scythian Plate and Mountain Crimea, North and South Kerch Zones and the other faults: Chongarskiy, Melitopol-Novotsarytsynskiy, Korsarsko-Feodosiyskiy, Gornostaevskiy and Kerch-Chkalivskiy. The Mykolayiv and West Crimean fault systems occur as large separate submeridional conductive zone. Deeper in the Earth’s crust and upper mantle, geoelectrical inhomogeneities are transformed into the subhorizontal structures (layers) and manifest themselves in regional anomalies. This fact may indicate the high permeability for deep fluids of contact zones during their formation. The deep sublatitudinal structure in the Earth’s crust is confidently traced, in the west it confirms and details the well-known Tarkhankut anomaly, and continues through the central Crimea to the northwestern part of the Kerch Peninsula. It is assumed that there is the strong sublatitudinal anomaly in the interior of the northwestern shelf of the Black Sea and in the northeastern part of the Kerch-Taman Depression at the crust — upper mantle boundary, it is contouring the Crimean Peninsula. The ultradeep fluid manifestation zones obtained according to seismotomography, the conductivity anomalies in the Earth’s crust and the upper mantle, increased heat flow and the spread of the earthquake hypocenters confirm the relationship between the Crimea seismicity and collision processes. It is shown the spatial coincidences of the hydrocarbon manifestations and the isolated conductivity anomalies, which are characterized by subvertical channels galvanically connected to sediments, or subvertical contact zones of different resistivity, which are observed not only in the Earth’s crust but also in the upper mantle layers (60—90, 110—140 km) and may cause the superdeep fluid inflow.

Existing notions on the distribution of carbon on the Earth have been considered in the article. By the example of the data on carbon content in the upper mantle of the Earth obtained in the west of the USA by deep seismic tomography method the appraisal of the resource potential of the interior has been made within the limits of the theory of the deep abiogenous-mantle origin of oil and gas. According to the given appraisal, the partly melted zone (reservoir) contains not less than 1.2·1017 kg of volatiles (Q, kg), such as H or C. Calculation by carbon (С) taking into account the initial data demonstrated that the weight content (concentration) of carbon per unit volume of the Earth crust and upper mantle for which the appraisals of carbon content were completed will be 1 333.3 kg/m3 or 1.3 t/m3 (1.3 g/cm3). With average amount of melt of the rocks of the upper mantle 0.5±0.2 % (per volume), the volume of the area of melting of the Earth crust (deep carbon reservoir), containing the appraised volume of volatiles, will be: 4.5·1011 m3. In such a notion the weight content (concentration) of carbon per unit volume of partly melted zone of deep carbon reservoir will be: 2.67·105 kg/m3 or 266.67 t/m3 (266.67 g/cm3). These are very high figures if not to say fantastically high, characterizing not only high content of carbon and hydrogen as the main donors of hydrocarbons but also characterizing concentration of these elements within definite zones of the upper mantle of the Earth (asthenospheric layer) by all components (composition, concentration, phase state, PT-conditions), which is referred by our opinion to the sources of deep oil and gas formation. The data presented allow us to affirm that the problem of donors of HC of deep, abiogenous-mantle genesis has been resolved in our concept, and the source has been determined with high probability of the primary donors of HC in the section of the mantle and iron-carbon core of the Earth having inexhaustible resources of primary carbon, with its phase composition depending on PT conditions of the terrestrial envelopes might be crystalline (diamond phase, iron and nickel compounds (Fen+Nin)+Cn, iron carbides, for example — FeC, Fe2C, Fe3C (cementite) et al.), liquid (for example, the melt with admixture of sulfur and other volatiles H-N-F-O-Cl) and gaseous (СО2 gaseous only in the mantle, higher than D″ layer). In this case HC synthesis in industrial volumes is realized in the process of hydrogenation of deep carbon on the ascending hydrogen streams within the limits of asthenospheric lenses favoured by the presence of reaction volume here, catalysts and the necessary PT-conditions for polymerization of hydrocarbon radicals.

The paper analyzes the characteristics of digital cameras with a set of inter-changeable lenses and extenders, which were part of the ISS RS standard equipment from 2001 to 2020 and were used by Russian cosmonauts to per-form visual observations of the Earth's surface in the interests of environmental examination of various areas and objects, improvement of methods of observation, evaluation and forecast of potentially hazardous or catastrophic phenomena. The paper also presents the features of photographic recording of ground objects using ultra-long focus optics.

Salt particles play important roles in many atmospheric processes due to their high hygroscopicity. Saline lakes and playas are sources of salt particles, which are normally mixed with mineral dust...

Magnesium (Mg) is a cheap, non-toxic, and recyclable alkaline earth metal that constitutes about 2% weight in the Earth’s crust. The use of magnesium catalysts to forge chiral moieties in molecules is highly attractive. Based on our work in recent years, we describe the current progress in the development of in situ generated magnesium catalysts and their application in asymmetric synthesis. In this perspective, a critically concise classification of in situ generated magnesium catalytic modes, with relevant examples, is presented, and representative mechanisms of each category are discussed. Building on the established diverse strategies, one can foresee that more innovative and structurally creative magnesium catalysts that are generated in situ will be developed to overcome more formidable challenges of catalytic enantioselective reactions.1 Introduction2 Magnesium Catalysts Generated in Situ from Chiral Ligands Containing Dual Reactive Hydrogens3 Magnesium Catalysts Generated in Situ from Monoanionic Chiral Ligands4 Bimetallic and Polymetallic Magnesium Catalysts Assembled in Situ5 Summary and Outlook

The bleaching process at the crude palm oil (CPO) refinery stage is one of the processes sufficient to determine the quality of the cooking oil produced. CPO is refined to eliminate the unacceptable substances before consumption. The process produces spent bleaching earth (SBE) and deoiled bleaching earth (DBE) classified as hazardous and toxic material waste. However, according to several studies, SBE and DBE have the potential as filler materials in NPK fertilizers. This study aimed to study the effect of SBE and DBE filler-based NPK fertilization on the soil nutrient status and growth characteristics of soybean, thereby determining if the SBE and DBE materials can be used to replace some of the filler components in the NPK fertilizers. The study was a single factor experiment arranged in a Randomized Complete Block Design (RCBD) consisting of four blocks as replications. The treatments tested were fertilization of 10% bentonite clay mineral filler-based NPK (control), 5% bentonite clay mineral + 5% SBE filler-based NPK and 5% bentonite clay mineral + 5% DBE filler-based NPK. The data were analyzed using ANOVA and tested using LSD test at a 95% confidence level. The results showed that the SBE and DBE materials could partially replace the filler components in bentonite clay filler-based NPK fertilizers, which were shown to have the same effect on soil chemical properties and levels of heavy metals after treatment, levels and uptake of N, P, K, Ca and Mg in plants tissues and growth characteristic in the form of total dry weight.

Toprak işleme makinaları sürüm işlemi yaparken, işleyici parçalar ile toprakta bulunan kuvars veya korundun gibi partiküller sürtünmektedir ve bu durum toprakta sürüm yapan işleyici tarım ekipmanlarında aşınmalara neden olmaktadır. Ülkemizde, bu ekipmanların mekanik özelliklerinin iyileştirilmesi ve aşınmaya karşı dirençlerini artırabilmek amacıyla uygulanan sertleştirme ısıl işlemleri gelişen teknikler ile birlikte değişmektedir. Yapılan çalışmada süneklik ve tokluk değerlerinin yüksek olduğu bilinen ve tarım aletlerinin belli bölümlerinde sıklıkla kullanılan 60SiMn5 alaşımına sertleştirme işleminden sonra farklı sıcaklıklarda (250 °C ve 270 °C) uygulanan menevişleme işlemlerinin mikroyapı ve mekanik özelliklerine etkileri incelenmiştir. Bu amaçla, 970 °C’ de östenitleştirme ve ardından yağda soğutma işlemi uygulandıktan sonra farklı sıcaklıklarda menevişleme işlemi uygulanmıştır. Uygulanan menevişleme işlemlerinin mikroyapıya etkisi optik mikroskop ve SEM-EDX analizleri ile gerçekleştirilmiştir. Numunelerin sertlik, darbe ve kuru kum kauçuk aşınma testleri gerçekleştirilmiştir. Çalışmanın sonucunda 270 °C’ de yapılan menevişleme işlemi ile numunede alt beynit yapısının daha homojen dağılmasının sağlaması sebebi ile malzemenin tokluk değerinde artış görülmüştür. Ayrıca uygulanan menevişleme işlemlerinin akma, çekme ve aşınma dayanımlarını arttırdığı ve mekanik özellikleri olumlu yönde etkilediği gözlemlenmiştir.

The paper presents author’s original and literature data on the standard free energy of 31 Sc ions and complexes in aqueous solution. Scandium behavior at the weathering of phyllite shales is physicochemically simulated with the Selector program package. The content of Sc in the shales is close to its average content in the Earth’s crust: 10–3 wt %. Solution in the weathering profile was determined to contain Sc practically only in the form of the hydroxocomplex $${\text{Sc}}({\text{OH}})_{3}^{0}.$$ The dissolved Sc concentrations is controlled by the solubility of its oxide Sc2O3 and phosphate ScPO4 and is lower than 10–9 mol/L.

In this study, the use of combined drain has been suggested as an alternative for triangular toe drain in a homogeneous earth dam. The main idea used in this research is to reduce the volume of dra...

Results are presented from the numerical modeling of two independent GLE events that occur at different times and have different energy characteristics of protons in primary particles. The resulting dependences are analyzed with allowance for features caused by characteristics of each spectrum.

New results of thermobarogeochemical studies show that quartz veins in the Drazhnoe deposit were formed under mesozonal conditions at a depth of 3–9 km from heterogeneous carbon dioxide–aqueous fluids with a low concentration of brines and high contents of CO2, which is typical of ore-forming fluids in orogenic vein gold deposits. Based on the phase composition, three types of fluid inclusions are distinguished: (1) carbon dioxide–aqueous; (2) gaseous, filled with dense carbon dioxide; and (3) a two-phase gas–liquid of aqueous–brine solutions. Na, Mg, and Fe chlorides predominated in the ore-forming fluids. It is assumed that the fluids migrated along the regional Adycha–Taryn shear zone and were uplifted to the Earth’s surface at a supra-lithostatic pressure, which was followed by precipitation of ore elements and the formation of quartz veins during tectonic movements along shear zones.

Tropical forests store large amounts of Earth’s terrestrial C, but many tropical montane streams have low dissolved organic matter (DOM). This low availability of energy likely limits certa...

The target bodies of C‐complex asteroid sample return missions are carbonaceous chondrite‐like near‐Earth asteroids (NEAs), chosen for the abundance and scientific importance of their organic compounds and “hydrous” (including hydroxylated) minerals, such as serpentine‐group phyllosilicates. Science objectives include returning samples of pristine carbonaceous regolith from asteroids for study of the nature, history, and distribution of its constituent minerals, organic material, and other volatiles. Heating after the natural aqueous alteration that formed the abundant phyllosilicates in CM and similar carbonaceous chondrites dehydroxylated them and altered or decomposed other volumetrically minor constituents (e.g., carbonates, sulfides, organic molecules; Tonui et al. 2003, 2014). We propose a peak‐temperature thermometer based on dehydroxylation as measured by analytical totals from electron probe microanalysis (EPMA) of matrices in a number of heated and aqueously altered (but not further heated) CM chondrites. Some CM lithologies in Maribo and Sutter’s Mill do not exhibit the matrix dehydroxylation expected for surface temperatures expected from insolation of meteoroids with their known orbital perihelia. This suggests that insolated‐heated meteoroid surfaces were lost by ablation during passage through Earth’s atmosphere, and that insolation‐heated material is more likely to be encountered among returned asteroid regolith samples than in meteorites. More generally, several published lines of evidence suggest that episodic heating of some CM material, most likely by impacts, continued intermittently and locally up to billions of years after assembly and early heating of ancestral CM chondrite bodies. Mission spectroscopic measures of hydration can be used to estimate the extent of dehydroxylation, and the new dehydroxylation thermometer can be used directly to select fragments of returned samples most likely to contain less thermally altered inventories of primitive organic molecules.

A way of calculating the field of solar radiation in Earth’s atmosphere is described that considers the thermodynamic non-equilibrium in the vibrational bands of CO2 and O3. The proposed technique allows calculations with high spectral resolution (line by line), along with parameterizations of the optical parameters of the Earth’s upper atmosphere that can be used in calculating the field of solar radiation.

Evaporative loss of sulfur from molten planetesimals can explain the sub-chondritic sulfur isotope composition of the bulk silicate mantle, suggesting an important role for planetesimal evaporation in establishing Earth’s volatile budget.

The efficacy of diatomaceous earth (DE) on growth rate, egg production and on increasing feed conversion efficiency in deep litter raised layer hens was evaluated. The study was conducted at Mukono Zonal Agricultural Research and Development Institute (MUZARDI) in Uganda. Worms were collected from fresh intestines of indigenous chicken obtained from Kalerwe chicken market near Kampala. The DE was mined in Pakwach (formerly Nebbi) district in Northern Uganda. Chickens of the Lohmann Brown breed raised on deep litter were studied. At 7 weeks the birds were divided into 5 treatment groups, A, B, C, D and E each composed of 40 birds. Groups C, D and E were given an oral dose containing 250 embryonated eggs of A. galli while groups A and B were not infected. The chicks were weighed; and subjected to feeding trials as arranged below: A – Non-infected birds on DE (4%) supplemented diet; B –non-infected birds on neither piperazine (a conventional de-wormer) nor DE; C – infected birds on DE supplemented diet; D – infected birds on piperazine; and group E – infected birds on neither DE nor piperazine applied. Fecal samples were collected and analysed in the laboratory biweekly at week 16 till week 22 respectively for fecal egg counts. In a subsequent experiment, day-old layer chicks from Lohmann Brown strain but different from those used in earlier experiments, were used to assess the effect of DE on egg production. At 17 weeks of age the 420 were divided as follows: 6 treatment groups each having 7 replicates and each replicate having 10 birds. This study showed that DE can be used successfully in growing pullet diets to correct nutritional mineral imbalance since it supplies more than 14 trace elements and other elements. Diatomaceous earth also enables pullets to cope with Ascaridia galli load; and 2% DE supplementation did not have significant improvement on egg production as compared to no supplementation at all. However, reduction in egg production was experienced when supplementation with levels of DE higher that 2% was applied. Results from biweekly fecal analyses showed significant differences in fecal egg counts (p

SUMMARYWe present a theory of modern, thermally induced deformation in a realistic Earth. The heat conduction equation is coupled with standard elastic deformation theory to construct a boundary-value problem comprised of eighth-order differential equations. The accurate and stable dual variable and position propagating matrix technique is introduced to solve the boundary-value problem. The thermal load Love numbers are defined to describe the displacements and potential changes driven by thermally induced deformation. The proposed analytical method is validated by comparing the present results with exact solutions for a homogeneous sphere, which are also derived in this paper. The analytical method is then applied to a realistic Earth model to evaluate the effects of layering and self-gravitation of the Earth on displacement and changes of potential. Furthermore, the frequency dependence in the thermal load is illustrated by invoking different thermal periodicities in the computation. Thermal anisotropy is also considered by comparing the results obtained using isotropic and transversely isotropic Earth models. Results show that, when simulating thermally induced deformation, invoking a homogeneous spherical Earth leads to results that substantially differ from those obtained using a more realistic Earth model.

Fluorite structured materials have shown their applicability in various fields both on and off Earth. In particular, these oxides find extensive application in nuclear energy and the use of actinid...

The chemical composition of aerosol particles strongly influences the earth’s climate, including their effects as sediments reducing the reflectivity of snow surfaces. Source apportionment and transportation pathways of such particles help to assess their contribution to regional surface-radiative heating. The chemical composition of particles in the free troposphere was studied at the Jungfraujoch (3580 m asl) in the Swiss Alps, using the laser mass spectrometer LAMPAS 2 during the CLACE-1 campaign. Statistical methods and lab measurements of reference particles were used to investigate the source and aging of field-measured particles. Desert sand, igneous rock and river sediment were used as model systems to differentiate between aged and non-aged atmospheric particles. Dried-up snow-water particles showed a particle composition typically found at the measurement site, largely influenced by carbonaceous and organic particles from local sources. During on-line measurements between 17 and 24 March 2000, sand particles from two sandstorm events were a significant source for less-aged mineral particles. Our results show that desert-sand particles can be transported over long distances and that silicate-rich particles in particular are only slightly altered in the atmosphere. We assume that both, the carbonaceous fraction as well as the fresh mineral particles lead to a warming effect at the measurement site due to their intrinsic properties of low solubility and strong light absorption, decreasing the surface reflectivity of the Alpine snow layer. The results allow for a better assessment of environmental influences and particles’ impact on the local climate in the Alpine region at the Jungfraujoch. Copyright © 2021 American Association for Aerosol Research

Despite being the most ubiquitous compound on Earth, the fundamental properties of water are not fully understood, especially in nanoconfinement. Densely grafted polyelectrolyte (PE) molecules atta...

The incorporation of water in nominally anhydrous minerals plays a crucial role in many geodynamic processes and evolution of the Earth and affects the physical and chemical properties of the main constituents of the Earth's mantle. Technological advances now allow the transport properties of minerals to be precisely measured under extreme conditions of pressure and temperature (P and T) that closely mimic the P–T conditions throughout much of the Earth's interior. This contribution provides an overview of the recent progress in the experimental studies on the influence of water on physical properties (i.e., diffusivity, electrical conductivity, thermal conductivity, sound velocity, and rheology) of olivine, wadsleyite, and ringwoodite together with their applications. In particular, consistency among various experimental data is investigated, discrepancies are evaluated, and confusions are clarified. With such progress in the experimental determination of transport properties of major mantle minerals, we can expect new insights into a broad range of geoscience problems. Many unresolved issues around water inside Earth require an integrated approach and concerted efforts from multiple disciplines.

Dams are structures designed primarily for water containment. They usually are found in areas with special transportation needs, either for mining purposes or for transporting heavy equipment, and with limited road infrastructure available. Heavy traffic over dams is discouraged, due to the damage this can cause to the integrity of the structure. The possible deformations caused by the passage of vehicles on the dam crest are not typically considered in the design of earth dams; however, the authorization of vehicle traffic on dams can be beneficial both economically and environmentally. A tolerance criterion is required to determine the allowable vehicle load on the dam crest. This paper presents an analysis of the permanent deformation caused in the core of a rockfill dam. Stress conditions that may be associated with a rapid accumulation of permanent deformation were identified, and an analysis method is proposed to specify the acceptable heavy traffic conditions for the dams.

The Advanced Very High Resolution Radiometers (AVHRR), which have been flying on National Oceanic and Atmospheric Administration’s (NOAA) polar-orbiting weather satellites since 1978, provide the longest global record of Earth observations from a visible–infrared imager. Experience gained through AVHRRs has been integral to the development of the new-generation sensors such as the Moderate Resolution Imaging Spectroradiometer (MODIS), the Visible Infrared Imaging Radiometer Suite (VIIRS), and associated data processing algorithms in the United States, as well as a similar class of sensor by space agencies around the world. Over four decades of data have been vital for studying Earth and its change. TheMetOp-Csatellite that was successfully launched in 2018 carries the last AVHRR. This article reviews the contributions of AVHRR in building a continuous global data record over the last 40 years on the occasion of its last launch.

This investigation was carried out to identify the engineering properties of compressed interlock earth blocks manufactured from locally available lateritic soil and introduce to use the manufactured soil blocks to minimize the material and finishing cost for the low cost housing projects. The soil samples used in this study were well-graded lateritic sandy soil which has the composition of 1.9% gravel, 94% sand and 4.1% silt / clay. These soil samples were passed through the 100-mesh sieve and mixed with ordinary Portland cement to prepare the admixture. While compressing through a hydraulics jack by varying the compositions and the volume of soil-cement admixtures, compaction soil blocks were manufactured in a locally fabricated 250 mm x125 mm x100 mm standard steel mould. The manufactured soil blocks allowed to cure while spraying small quantity of water and covering with polythene for 28 days. Average compressive strengths of soil blocks made with 5% cement with 1.6:1 and 1.8:1 volume compactions were 1.3 Mpa and 1.9 Mpa, respectively. However, both compressive strength values were less than the standard limits of 2.8 MPa stated in SLS 1382:2009, local standards for soil blocks used for construction industry. However, soil blocks made with 10% cement under same compaction ratios attained compressive strengths of 3.0 MPa and 3.6 MPa respectively and it is above the required standards limits. However, 15% and 20% cement containing earth blocks have much higher compressive strengths but increase the cost of production. Regression analysis results confirmed the strong correlation between cement content and the compressive strength of the soil bricks. The soil bricks manufactured with more than 12.06% cement soil mix by maintaining compaction ratio into 1.6:1 or Soil bricks manufactured with more than 5.16% cement mix by maintaining compaction ratio into 1.8:1 will produce standards soil bricks for construction industry and these results further confirmed that wet and dry compressive strength of soil bricks will increase with increasing the compaction ratio and the cement content. However, when considering the compressive strength, water absorption level and cost effectiveness, soil bricks manufactured by maintaining compaction ratio into 1.8:1 with more than 5.16% cement mix will produce required standards cost effective soil bricks for construction industry.

The results of experimental studies at the hydrogen production site, hydrogen degassing sites in various regions, as well as on the Moon are presented. Experiments using the direct-prospecting technology of frequency- resonance processing and interpretation of satellite images and photographs are carried out in order to study the features of the deep structure in the areas of hydrogen degassing. The results of instrumental measurements indicate that, in the areas of the basalt volcanoes location with roots at different depths, signals at hydrogen frequencies are almost always recorded. When scanning the cross-section, responses from hydrogen are recorded practically from the upper edges of basalt volcanoes to their roots. Therefore, it can be assumed that basaltic volcanoes are a kind of channels through which hydrogen migrates to the upper horizons of the crosssection and further into the atmosphere. Deep (living) water is synthesized within many basalt volcanoes at a depth of 68 km. Hydrogen-rich water is healing and can be used for wellness purposes. All previously surveyed longevity zones on the Earth are located within basalt volcanoes, in which water synthesized at a depth of 68 km migrates to the surface and is used for the water supply. Hydrogen deposits can be formed by basaltic volcanoes in adjacent sealed reservoirs. The Mali hydrogen production site is located outside the contour of the basalt volcano; hydrogen responses were recorded from marl at the well site. At local sites in the Carpathians, signals from hydrogen are obtained from dolomites and marls. Hydrogen deposits formed near basalt volcanoes in different types of reservoirs can be discovered and localized during areal exploration using the methods of frequency- resonance processing of satellite images and photographs. Direct-prospecting technology can also be used to study reservoirs in crystalline rocks (including basalts). The materials of the article, as well as the previously published results of experimental work in various regions, indicate the advisability of using direct-prospecting methods of frequency–resonance processing of satellite images and photographs to detect zones of hydrogen accumulation in areas, where basalt volcanoes are located, as well as in areas of hydrogen degassing. The use of the mobile low-cost technology will significantly speed up the exploration process for hydrogen, as well as reduce the financial costs for its implementation.

Manganese (Mn) oxides have been prevalent on Earth since before the Great Oxidation Event and the Mn cycle is one of the most important biogeochemical processes on the Earth's surface. In sunlit natural environments, the photochemistry of Mn oxides has been discovered to enable solar energy harvesting and conversion in both geological and biological systems. One of the most widespread Mn oxides is birnessite, which is a semiconducting layered mineral that actively drives Mn photochemical cycling in Nature. The oxygen-evolving centre in biological photosystem II (PSII) is also a Mn-cluster of Mn4CaO5, which transforms into a birnessite-like structure during the photocatalytic oxygen evolution process. This phenomenon draws the potential parallel of Mn-functioned photoreactions between the organic and inorganic world. The Mn photoredox cycling involves both the photo-oxidation of Mn(II) and the photoreductive dissolution of Mn(IV/III) oxides. In Nature, the occurrence of Mn(IV/III) photoreduction is usually accompanied with the oxidative degradation of natural organics. For Mn(II) oxidation into Mn oxides, mechanisms of biological catalysis mediated by microorganisms (such asPseudomonas putidaandBacillusspecies) and abiotic photoreactions by semiconducting minerals or reactive oxygen species have both been proposed. In particular, anaerobic Mn(II) photo-oxidation processes have been demonstrated experimentally, which shed light on Mn oxide emergence before atmospheric oxygenation on Earth. This review provides a comprehensive and up-to-date elaboration of Mn oxide photoredox cycling in Nature, and gives brand-new insight into the photochemical properties of semiconducting Mn oxides widespread on the Earth's surface.

This paper makes a case for why Hawaii is the rainbow capital of the world. It begins by briefly touching on the cultural and historical significance of rainbows in Hawaii. Next it provides an overview of the science behind the rainbow phenomenon, which provides context for exploring the meteorology that helps explain the prevalence of Hawaiian rainbows. Last, the paper discusses the art and science of chasing rainbows.

The electrical conduction mechanism of the hydrous minerals under high pressure is of great significance for understanding the high conductivity of the mantle and the Earth’s internal water. Theref...

Low molecular weight dicarboxylic acids constitute a large fraction of atmospheric organic aerosols, which impact atmospheric radiative forcing and hence Earth’s climate. Radiocarbon (14C) is a uni...

Recent fluid flow in ancient meteoritesCarbonaceous chondritic meteorites are thought to be fragments broken off parent bodies that orbit in the outer Solar System, largely unaltered since their formation. These meteorites contain evidence of reactions with liquid water that was thought to have been lost or completely frozen billions of years ago. Turneret al.examined uranium and thorium isotopes in several carbonaceous chondrites, finding nonequilibrium distributions that imply that uranium ions were transported by fluid flow. Because this signature disappears after several half-lives of the radioactive isotopes, the meteorites must have been exposed to liquid within the past million years. The authors suggest that ice may have melted during the impacts that ejected the meteorites from their parent bodies.Science, this issue p.164

The discrimination and detection of phosphate anions have attracted extensive attention due to their important roles in various biological processes. Compared with sensors to detect one individual phosphate at a time, sensor arrays are able to discriminate multiple phosphates simultaneously. In this study, we developed a rare earth ions enhanced AuNCs-based sensor array to achieve facile and rapid identification of phosphate anions (PPi, ADP and ATP). The rare earth ions (i. e., Ce3+ , Gd3+ , Tm3+ and Yb3+ ) can significantly enhance the fluorescence of AuNCs through aggregation-induced emission effect. And the subsequent addition of phosphate anions can recover the fluorescence of the AuNCs-rare earth ions assembly. Thanks to the different numbers of phosphate group and different steric hindrance effects of phosphate anions, the recovery fluorescence of AuNCs-rare earth ions assembly induced by PPi, ADP or ATP are respectively distinct. Thus the sensor array composed of AuNCs and different rare earth ions is able to distinguish those phosphate anions. Finally, the sensor array was successfully demonstrated to identify the phosphates in blind samples.

We derive a theoretical parameter for three seismic scattering regimes where seismic wavelengths are either much shorter, similar, or much longer than the correlation length of small-scale Earth heterogeneities. We focus our analysis on the power spectral density (PSD) of the von Karman autocorrelation function (ACF), used to characterize the spatial heterogeneity of small-scale variations of elastic rock parameters that cause elastic seismic-wave scattering. Our analysis is based on the assumption that the PSD of the medium heterogeneities at the corresponding wavenumber is related to the wavefield scattering. Our theoretical findings are verified by numerical simulations. The seismic scattering effects in our simulations are assessed by examining attenuation of peak ground acceleration. We discover (1) that seismic scattering is proportional to the standard deviation of velocity variations in all three regimes, (2) that scattering is inversely proportional to the correlation length for the regime where seismic wavelengths are shorter than correlation length, but directly proportional to the correlation length in the other two regimes, and (3) that scattering effects are weak due to heterogeneities characterized by a gentle decay of the von Karman ACF for regimes where seismic wavelengths are similar or much longer than the correlation length.