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This paper presents recently obtained palebotanical data regarding the evolution of Lake Paleolotos in the Middle Pleistocene. Its evolution was more complicated than the development of the adjacent lakes in the coast of Peter the Great Bay (the Sea of Japan). The Middle Pleistocene lacustrine sediments accumulated in the downstream of the Tumannaya River (the most southwestern area of Primorye, Russia Far East) were studied using diatom and pollen analytical methods. We found that the Lake Paleolotos arose during Marine Isotope Stage 11 (MIS 11) and disappeared during MIS 6. For more than half of its existence (MIS 11–8), it was a freshwater oligotrophic basin with a depth of at least 20 m, with clear waters and poor organic matter content. The lake occupied most of the modern accumulative plain on the left bank of the Tumannaya River, reaching a size of at least 10–12 km across. During MIS 7–6 Lake Paleolotos turned into a shallow-water basin (its depth most likely did not exceed 1–3 m) of a eutrophic type with turbid waters rich in organic matter. Palynological data suggest that during MIS 11, 9 and 7 the area adjacent to the Lake was covered with coniferous/broad-leaved forests with presence of some thermophilic plants of North China and North Korea Flora (Castanea , Celtis , Magnolia , Tsuga and Cupressaceae). This indicates that vegetation zones were displaced by about 500–700 km to the north relative to their present position. During periods of cooling they were replaced by coniferous/small-leaved forests with the participation of shrub species of birch and alder (MIS 10) and coniferous/small-leaved forests consisted of pine, birch, and spruce with the participation of elm and oak (MIS 8 and 6). [ABSTRACT FROM AUTHOR]

Activated carbon fiber, also known as the third generation of activated carbon material, is a new type of activated carbon material after powder and granules, made of the organic fiber. Activated carbon fiber has a strong adsorption capacity due to its large specific surface area, and can adsorb and remove organic matter in water, including some carcinogenic or toxic macro-aromatic substances. Physical adsorption is caused by electrostatic interaction between the surface molecules of the adsorbent and the adsorbate molecules, which is characterized by adsorption without selectivity. Chemical adsorption is due to the chemical bonding between the two molecules, forming a strong chemical bond and also the surface complex. Chemical adsorption has the certain selectivity, generally monolayer adsorption. With the large increase in vehicle usage and the exhaust emissions from equipment such as oil-fired boilers, the pollution of nitrogen oxides and carbon monoxide gas has become an important issue in environmental management. Adsorption or catalytic conversion of nitrogen oxides and carbon monoxide is an important means of treatment. This paper integrates the smart city scenario to construct the novel scenario for the analysis and research. The simulation results prove the effectiveness. [ABSTRACT FROM AUTHOR]

[Display omitted] • Soils under anthropic uses showed more remarkable changes in soil properties with rainfall seasonality than soils under natural páramo. • Land-use change from natural vegetation to potato and onion crops followed by fallow reduces soil organic matter and water content and increases bulk density. • Land-use change could impair the ability of páramo catchments for streamflow buffering and this could increase surface runoff and reduce base flow. High-Andean páramos deliver essential ecosystem hydrological services from a combination of soil, vegetation, and climate characteristics, particularly in their natural state. However, agricultural activities considerably affect the páramo's ability to store, regulate, and supply water. Although there is information on the effect of potato crops (Solanum tuberosum) on páramo soils' properties, the effect of spring onion (Allium fistulosum) crops has been studied less. In addition, dry páramos are underrepresented in existent páramoś research. This study assessed the effect of rainfall seasonality (RS) and land-use change (transformation from páramo vegetation to crops) on soil hydrophysical properties associated with hydrological services (streamflow buffering) in a dry páramo in the Eastern range in Colombia. Six dominant land uses were studied: natural páramo vegetation (low slope, steep slope, and dense shrublands) and anthropic use (onion crops, potato crops, and fallow). An in-depth random stratified discrete design (0–5, 10–15, and 20–25 cm) was used to collect samples for analysis of soil organic matter (SOM), bulk density (BD), pH, and electrical conductivity (EC). Hydrophysical properties were measured at the soil surface: water retention capacity (WRC), structural stability (SS), and infiltration capacity (IC). Soils under anthropic uses showed more remarkable changes in soil properties with RS than soils under natural páramo. On the other hand, land-use change from natural vegetation to potato and onion crops followed by fallow leads to a reduction in SOM (9.8 %) and an increase in BD (0.19 gcm−3), especially at the surface level. In addition, this leads to a loss of WRC (20 % at field capacity), an increase in unstable aggregates (13 %), water erosion, and a loss of IC (44 mmh−1). This paper demonstrates the impact of land use on soil hydrophysical properties that compromise the maintenance of hydrological services and contributes to a better understanding of the complexity of Andean páramos. [ABSTRACT FROM AUTHOR]

Coal gasification technology is the core of clean and efficient utilization of coal, while coal gasification fine ash (CGFA) is the solid waste inevitably produced in the coal gasification process. Due to the high residual carbon content and water retention of CGFA, the solubility of its silica-aluminium-calcium-containing minerals is poor, which affects its potential cementing properties in construction materials. In this paper, the basic physicochemical properties were investigated, and it was found that small particles of CGFA (CGFA-S) had more active mineral components, lower residual carbon content (17.17%) and weaker water retention (6.91%), which facilitated the removal of impurities and water. In addition, the best effects were achieved at a heat treatment temperature of 650 °C, which exposed the minerals and increased the solution solubility, and the leaching concentrations of Si4+, Al3+, and Ca2+ increased by 21.2%, 44.6%, and 97.8%, respectively. However, when the temperature was too high (815 °C), the minerals recrystallized, leading to structural instability and dissolution difficulties, and the concentrations of the three major ions were reduced by 84.4%, 82.0%, and 42.2%, respectively, compared with the control.Finally, the optimal heat treatment temperature was 650 °C, with the highest exothermic hydration rate (11.92 mW/g) and the highest cumulative exothermic heat (199.81 J/g). The hydration products were tightly bound, and the cement mortar specimens had the highest compressive strength, with a 28d strength of 45.4 MPa. • The physicochemical properties of CGFA were analyzed based on particle size. • The extraction effect and microstructure of ash in CGFA were tested. • The hydration activity of thermally modified CGFA was investigated. [ABSTRACT FROM AUTHOR]

There is still no direct evidence for the existence of water ice and organic matter on the moon. The main goal of developing a miniature time-of-flight mass spectrometer (TOF MS), Lunar Water Molecular Analyzer Mass Spectrometer (LWMA MS), is to detect water ice, organic matter and other chemical components in situ on the moon. The miniature LWMA MS in this paper is composed of sampling introduction tube, gas charge tube, ion source, TOF mass analyzer and detector. The SIMION software was used to simulate the miniaturization design of the ion source and mass analyzer. Meanwhile, the developed miniature TOF MS was evaluated systematically. Its resolution is 151 for water and 163 for nitrogen, the mass range is from 1 to 500 amu, the stability of water is 3% during 12 h. Moreover, it was proved that the developed LWMA MS is able to detect water ice and organic matter through the experiments of the lunar soil simulant. • A miniature LWMA MS is developed. • The resolution is 151 for water and 163 for nitrogen. • The mass range is from 1 to 500 amu. • The stability of H 2 O is 2.98% for 12 h. • The designed LWMA MS is able to detect the water ice and organic matter in situ lunar investigations. [ABSTRACT FROM AUTHOR]

• Water content data in liquid CO 2 between (-55 and -10)°C • Impact of impurities on the dehydration requirement. • Two different modelling approaches used to calculate water content CCS is expected to become an important contribution to the mitigation of carbon dioxide emissions. Transportation of CO 2 from the capture site to the permanent storage reservoir plays a key role, and transportation by ship is now viewed as a relevant alternative for certain combinations of captured CO 2 volume and distance. This paper presents experimental equipment, methods and new results for the water content of carbon dioxide and impure carbon dioxide in equilibrium with hydrates at temperatures between (-55 and -10)°C and pressures between (3 and 120) bar, hence in both vapour and liquid phases. The experimental data are compared with predictions from two thermodynamic models: the Cubic-Plus-Association equation of state and an approach using Multi-Fluid Helmholtz Energy Approximation (MFHEA) equations of state (EoS). In all cases, the hydrate-forming conditions are modelled by the solid solution theory of van der Waals and Platteeuw. [Display omitted] [ABSTRACT FROM AUTHOR]

• A visual platform that combined Raman spectrometer was built to observe water at temperatures from 293 K to 1013 K. • The extent of hydrogen bonding in liquid water and supercritical water were estimated. • Compared with temperature, density has a greater effect on the degree of hydrogen bonding in supercritical water. • Hydrogen bonds still exist in supercritical water even at temperature of 1013 K (ρ = 49.8 g/L). Supercritical water is widely used as a superior reactant or solvent in the gasification of biomass and coal. Research shows that hydrogen bonding could reduce the potential energy of chemical reaction between water molecules and organic molecules. However, it is still uncertain whether hydrogen bonds exist in supercritical water at the temperature of coal gasification process (above 873 K). In this paper, a high temperature and pressure visualization platform (T max = 1013 K) was built. The hydrogen bonding degree of water from liquid to supercritical is obtained in a wider temperature range. It is a remarkable fact that hydrogen bonds still exist in supercritical water even at temperatures as high as 1013 K. These hydrogen bonds mainly exist in the form of dimer and trimer, which is a significant factor that can't be ignored in the study of gasification mechanism of coal and organic matter in supercritical water. [ABSTRACT FROM AUTHOR]

The Transpolar Drift (TPD) is a mechanism for the rapid transport of shelf-modified Siberian river waters across the Arctic Ocean and out through Fram Strait. We present results from three trans-Arctic research cruises in August–September 2014–2016 to investigate the distribution and dynamics of dissolved organic matter (DOM) in the upper waters across the North Pole, from Svalbard to the Mackenzie River mouth, and in two important outflow gateways of the Arctic Ocean (Fram Strait and Lancaster Sound). Fluorescence measurements of DOM obtained using in situ sensor and laboratory-based spectroscopic analyses, coupled with parallel factor analysis (PARAFAC) were used to map components of DOM at high spatial resolution. The optical properties showed a completely different composition with a much stronger humic-like signal observed in surface waters in the Makarov Basin than in the adjacent Canada Basin, likely due to the substantial amount of Siberian runoff transported by the TPD. The high levels of humic-like in TPD-influenced surface waters were traced from southern Makarov shelves up to the Lomonosov Ridge near the North Pole. Lower DOM levels were observed in the eastern Amundsen basin waters, likely the result of mixing with terrestrial-poor DOM Atlantic waters. The annual flux of humic-like C2 transported to the Atlantic through Fram Strait was estimated at 1816 ±926 r.u. km3. This study reveals the importance of shelf processes and TPD in supplying humic-like material to the central Arctic Ocean to Fram Strait. • Significant differences in fluorescence composition were found between the four main Arctic basins. • A much stronger terrigenous signal was observed in Makarov Basin waters than in the adjacent Canada Basin. • The annual flux of humic-like transported to the Atlantic Ocean was estimated at 1816± 926 r.u. km−3 [ABSTRACT FROM AUTHOR]

Cold-water corals (CWCs) are important ecosystem engineers in the deep sea that provide habitat for numerous species and can form large coral mounds. These mounds influence surrounding currents and induce distinct hydrodynamic features, such as internal waves and episodic downwelling events that accelerate transport of organic matter towards the mounds, supplying the corals with food. To date, research on organic matter distribution at coral mounds has focussed either on seasonal timescales or has provided single point snapshots. Data on food distribution at the timescale of a diurnal tidal cycle is currently limited. Here, we integrate physical, biogeochemical, and biological data throughout the water column and along a transect on the south-eastern slope of Rockall Bank, Northeast Atlantic Ocean. This transect consisted of 24-h sampling stations at four locations: Bank, Upper slope, Lower slope, and the Oreo coral mound. We investigated how the organic matter distribution in the water column along the transect is affected by tidal activity. Repeated CTD casts indicated that the water column above Oreo mound was more dynamic than above other stations in multiple ways. First, the bottom water showed high variability in physical parameters and nutrient concentrations, possibly due to the interaction of the tide with the mound topography. Second, in the surface water a diurnal tidal wave replenished nutrients in the photic zone, supporting new primary production. Third, above the coral mound an internal wave (200 m amplitude) was recorded at 400 m depth after the turning of the barotropic tide. After this wave passed, high quality organic matter was recorded in bottom waters on the mound coinciding with shallow water physical characteristics such as high oxygen concentration and high temperature. Trophic markers in the benthic community suggest feeding on a variety of food sources, including phytodetritus and zooplankton. We suggest that there are three transport mechanisms that supply food to the CWC ecosystem. First, small phytodetritus particles are transported downwards to the seafloor by advection from internal waves, supplying high quality organic matter to the CWC reef community. Second, the shoaling of deeper nutrient-rich water into the surface water layer above the coral mound could stimulate diatom growth, which form fast-sinking aggregates. Third, evidence from lipid analysis indicates that zooplankton faecal pellets also enhance supply of organic matter to the reef communities. This study is the first to report organic matter quality and composition over a tidal cycle at a coral mound and provides evidence that fresh high-quality organic matter is transported towards a coral reef during a tidal cycle. [Display omitted] • We measured physical conditions and food supply at a cold-water coral reef over 24h. • Large variability in environmental conditions and food supply over the tidal cycle. • Internal waves transport fresh organic matter to the cold-water coral reef. • Organic matter delivered to the cold-water coral reef is of high quality. • The reef community feeds on variety of sources, but depends on surface production. [ABSTRACT FROM AUTHOR]