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The sedimentary basin is a basic geological unit in the Earth system: its formation and evolution are controlled mainly by plate tectonics and geodynamics, which have produced a variety of basin types. The development and evolution of various basins depend not only on the tectonic effect of lithospheric plate but also on sublithospheric, and Earth surface actions. Basin classification schemes based on the theories of platform–geosyncline or plate tectonics could neither include all basin types nor reflect the complex processes of basin formation and evolution. From the viewpoint of Earth system, we proposed a new basin classification scheme based on geodynamic mechanism—that is, lithospheric plate, sublithospheric, and Earth surface actions. In our geodynamic classification, we employed a series of geodynamic settings of basin formation and evolution, including the lithospheric plate, sublithospheric, and Earth surface environments, the dynamic regimes of basin formation and evolution, such as tectonic setting (extension, compression and shearing), the thermal processes and gravity effects, the various natures of basin basement and crustal types (continental, oceanic, or transitional crust), and the history of basin sedimentary filling and tectonic paleogeography successively, as the controlling factors for basin classification. This new geodynamic classification scheme highlights both the role of the lithosphere and the effects of the sublithospheric and the Earth surface actions on controlling the basin formation and evolution. The basic dynamic types of basin classification include the prototype basin forming under a single tectonic, thermal, or gravity regime and the superimposed basin as well as residual basin forming under multistage thermal and/or tectonic regimes. Thus, this classification scheme could provide an evolving understanding of lithosphere, crust–mantle interaction, and geodynamic processes as well as of hydrocarbon accumulation and metallogenic mechanisms in sedimentary basins and would help in the synthetic exploration of various resources.

In this paper we consider a fluid-fluid system coupled with a friction-type interface condition which is described by a jump of the velocities along the tangential interface. Based on domain decomposition, we propose a Schwarz type iterative method to decouple the different physical process in each subdomain occupied by a single fluid, which allows solving in each subdomain only the physical process described by a Stokes problem. Using energy estimate, we prove that the algorithm converges for any traction coefficient. A more detailed analysis based on Fourier analysis shows that the convergence rate depends on both the fluids' properties, the traction coefficient and the time stepsize, but is independent of the spatial mesh. We finally use numerical examples to illustrate the theoretical results.

The complex pore system in tight sandstone reservoirs controls the storage and transport of natural gas. Thus, quantitatively characterizing the micro-nanopore structure of tight sandstone reservoirs is of great significance to determining the accumulation and distribution of tight gas. The pore structure of reservoirs was determined through polarizing microscopy, scanning electron microscopy (SEM), and the combination of mercury injection capillary pressure (MICP) and nuclear magnetic resonance (NMR) experiments on Late Paleozoic conventional and tight sandstone samples from the Linxing Block, Ordos Basin. The results show that in contrast to conventional sandstone, dissolution pores, with diameters less than 8 μm, are the main contributors to the gas storage space of tight sandstone reservoirs. The pore size distribution derived from the MICP experiment demonstrates that the main peak of tight sandstones corresponds to a pore radius in the range of 247 nm to 371 nm, while the secondary peak usually corresponds to 18 nm. The results of the NMR test illustrate that the T2 spectra of tight sandstones are unimodal, bimodal and multimodal, and the main NMR peak is highly related to the MICP peak. Fractal theory was proposed to quantitatively characterize the complex pore structure and rough porous surface. The sandstones show fractal characteristics including nanopore fractal dimension DN obtained from the MICP and large pore fractal dimension DL obtained from the NMR experiment. Both DN and DL are positively correlated with porosity and negatively correlated with permeability, demonstrating that complex and heterogeneous pore structure could increase the gas storage space and reduce the connectivity.

A series of organic-rich shale samples from various shale gas reservoirs that experienced complex structural change around the Sichuan Basin of the Upper Yangtze Block, South China, have been studied with respect to their microstructural and petrophysical variations, using mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). Deformed samples were chosen as being representative of various degrees of deformation intensity, and undeformed samples (reference primary structure shales) were sampled outside the main deformed zones. In most of the examples explored, porosity, permeability, and fracture varied with the degree of structural deformation at the micrometer or even nanometer scale, changing and in most cases increasing the deformed shales's ability to store and transport hydrocarbon molecules. Quartz and carbonates are primarily responsible for petrophysical variations, but tectonism can strongly influence these existing relations. Porosity varies by up to one to two times in extreme cases, but the average porosity increase is about one time. Permeability increases by up to three to four orders of magnitude in extreme cases, but the average permeability increase is about two to three orders of magnitude. These ranges depend heavily on the development of abundant natural micro-fractures and micro-channels. Six major fracture types, including matrix micro-fracture, mineral-related micro-fracture, OM-related micro-fracture, fracture-edge micro-channel, pore-edge micro-channel, and intragranular micro-channel, have been identified and classified by size, location, and geometry. Furthermore, possible formation mechanisms for these fractures, such as grain crushing, grain cracking, grain folding, and grain spacing, have been proposed and discussed. This study highlights the tectonic processes for natural fracture formation and their changes in porosity and permeability. These results have significant implications for understanding methane storage and fluid migration in naturally deformed shale reservoirs, and they could prove important for evaluating and predicting producible resources.

The Fenton oxidation of nuclear grade cationic exchange resin was investigated in view of the effects of initial temperature, H2O2 dosage, catalyst type and concentration as well as initial pH. Initial temperature and H2O2 dosage exhibited a significant positive effect on the decomposition of cationic resins, whereas the initial pH showed a negative effect. Ferrous ions had higher catalytic ability than copper ions to the H2O2 activation for resin decomposition, and the best Fe2+ concentration was 0.3 M. Under the conditions of initial temperature of 75 °C, H2O2 dosage of 200 mL, Fe2+ concentration of 0.3 M and initial pH of 0.01, a weight reduction of 73% was achieved. The experimental results on Co-substituted mock samples indicated that the radionuclides loaded in the resins were concentrated in liquid residue. The decomposition of cationic resins followed the two-stage first-order kinetics that composed of a dissolution period of resin beads (first-stage) and a followed degradation stage of resin solution (second-stage). Combined with the UV–visible and infrared spectra and their corresponding density functional theory (DFT) calculations, the dissolution of resin beads was due to the desulfonation of the sulfonated aromatic rings and the oxidative fragmentation of the polymer backbone by hydroxyl radicals ( OH) formed in Fenton reactions. After the dissolution of resin beads, the oxidative degradation and mineralization process proceeded by the attack of OH mainly in aqueous medium.

Three-dimensional macroporous graphene-wrapped zero-valent copper nanoparticles (3D-GN@Cu0) were synthesized using a self-assembly process of liquid-phase reduction and characterized by field emission scanning electron microscopy, nitrogen adsorption/desorption isotherms, X-ray diffraction, Raman spectrum analysis, and X-ray photoelectron spectroscopy. The catalytic activity of 3D-GN@Cu0 was evaluated in view of the effects of various systems, the pH value, catalyst dosage, initial metronidazole concentration and temperature, and it showed a high efficiency for removing metronidazole with saturated dissolved oxygen (without adding extra H2O2) in a wide range of pH value from 3.2 to 9.8. Combined with the results of dissolved oxygen activation, determination of reactive oxidizing species, and X-ray photoelectron spectroscopy (XPS) analysis, the surface-bounded ·OHads formed by the reaction of the in situ generation H2O2 with 3D-GN@Cu0 was mainly responsible for the removal of metronidazole. The charge distribution and electrostatic potential (ESP) of 3D-GN@Cu0 further illustrated the distribution and transfer of electrons on the catalyst surface, which predicted a micro-electrolysis-promoted Fenton-like reaction mechanism.

The nanopore network in organic-rich shale plays a key role in shale gas storage and migration, and micropores are an important structural unit in connecting the migration channel. In this study, we selected six non-marine coal-bearing shales from the Qinshui Basin to investigate the effect of composition on micropore structure using X-ray diffraction, total organic carbon (TOC), vitrinite reflectance, and CO2adsorption methods. The results indicate that non-marine shale with higher TOC content possesses more micropores, leading to a more complex pore structure and improving the heterogeneity of shale reservoirs. With the increase in TOC content, the micropore surface area and micropore volume clearly increases, which greatly improves the gas storage space in shale reservoirs. The thermal evolution of organic matter promotes the development of micropores to a certain extent in non-marine shale. Clay minerals possess a rough surface and develop more micropores, and their influence on the micropore structure of non-marine shale is relatively strong, while terrestrial quartz exhibits significant micropore development. The obviously positive correlations between micropore volume and kaolinite, chlorite contents in the non-marine shale suggest that kaolinite and chlorite make a certain contribution to micropore volume. The characteristics of micropore structures in coal mainly depend on lithotypes, TOC content, and ash content, while clay content, quartz content, and TOC content are the key factors controlling the formation of micropores in non-marine shale.

The structure and fractal characteristics of nanopores of high-rank coal were investigated using an approach that integrates N2 adsorption and field emission scanning electron microscopy (FE-SEM). The results indicated that the high-rank coal of the Shanxi Formation has a complex pore-fracture network composed of organic matter pores, mineral-related pores, and microfractures. The pore type of high-rank coal tends to be complicated, and the main pore types are inkbottle pores and open pores, which are more conducive to methane enrichment. The Ro,max has a negative relationship with the total pore volume. In addition, the ash and inertinite contents show a positive correlation with the average pore size (APS), while the fixed carbon content exhibits a negative relationship with the APS. The pore structure of high-rank coal is controlled not only by the degree of metamorphism but also by coal composition, which leads to the variation in pore structure becoming more complicated. With the increase in coal metamorphism, high-rank coal with high amounts of fixed carbon content generally possesses a higher irregularity in pore structure. No obvious relationship was observed between D2 and the coal components, which indicates that the pore structure, ash content, moisture content and other factors controlled by the metamorphism of coal have different effects on D2 that lead to this inapparent relationship. A negative relationship exists between adsorption volume and D1, which indicates that the high irregularity of the pore structure is not conducive to methane absorption and that no obvious correlation exists between the adsorption volume and D2. In the high-rank coal, the high D1 value represents the complexity and heterogeneity of the pore structure and represents a low adsorption affinity for methane molecules; in addition, D2 has no effect on the methane adsorption capacity.

The mineralogical and compositional characteristics of gold-bearing minerals and the occurrence of gold are not only of great significance to exploring the sources of ore-forming materials and their formation mechanisms but also helpful for designing reasonable beneficiations and smelting schemes and achieving remarkable economic benefits. This paper presents an integrated study on the crystal characteristics, elemental composition and distribution of pyrite (the main gold-bearing minerals), on the basis of electron probe microanalysis (EPMA), scanning electron microscopy (SEM), laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) and nano-secondary ion mass spectrometry (NanoSIMS). The occurrence of gold in the Shuiyindong gold deposit and Ashawayi gold deposit has been studied by means of microscopy, SEM, and EPMA images, elemental correlations, S–Fe–As ternary diagrams, logAs–logAu diagrams and Au/As ratios. The gold in pyrite of the Shuiyindong deposit is in the form of nano gold inclusions and lattice gold. The gold in pyrite of the Ashawayi deposit dominantly exists in the form of nano gold inclusions or is present as micro-nano gold particles in the cracks or edges of pyrite, some of which can exist as lattice gold. The ore-forming hydrothermal solution of the Shuiyindong gold deposit is mainly underground hot brine, but it may be reformed by a deep magmatic hydrothermal solution or volcanic-subvolcanic hydrothermal solution. The ore-forming hydrothermal solution of the Ashawayi gold deposit is mainly derived from the metamorphic hydrothermal solution formed during the orogenic process, and the ore-forming process or post-mineralization process may be reformed by the leaching of underground hot brine. Finally, the characteristics of ore-forming fluids and evolution of the two types of deposits are determined via pyrite element surface scanning. This paper shows that micro-nanoscale study of gold-bearing pyrite is of great significance to understanding the gold mineralization process and is worth further study.

The western Sichuan hydrothermal area is located at the northeastern margin of the eastern syntaxis of the Qinghai-Tibet Plateau, which is also the eastern end of the Mediterranean-Himalayan geothermal activity zone. There are 248 warm or hot springs in this area, and 11 have temperatures beyond the local boiling temperature. Most of these hot springs are distributed along the Jinshajiang, Dege-Xiangcheng, Ganzi-Litang, and Xianshuihe faults, forming a NW-SE hydrothermal belt. A geothermal analysis of this high-temperature hydrothermal area is an important basis for understanding the deep geodynamic process of the eastern syntaxis of the Qinghai-Tibet Plateau. In addition, this study offers an a priori view to utilize geothermal resources, which is important in both scientific research and application. We use gravity, magnetic, seismic, and helium isotope data to analyze the crust-mantle heat flow ratio and deep geothermal structure. The results show that the background terrestrial heat flow descends from southwest to northeast. The crustal heat ratio is not more than 60%. The high temperature hydrothermal active is related to crustal dynamics processes. Along the Batang-Litang-Kangding line, the Moho depth increases eastward, which is consistent with the changing Q c/ Q m (crustal/mantle heat flow) ratio trend. The geoid in the hydrothermal zone is 4–6 km higher than the surroundings, forming a local “platform”. The NW-SE striking local tensile stress zone and uplift structure in the upper and middle crust corresponds with the surface hydrothermal active zone. There is an average Curie Point Depth (CPD) of 19.5–22.5 km in Batang, Litang, and Kangding. The local shear-wave ( S -wave) velocity is relatively low in the middle and lower crust. The S -wave shows a low velocity trap ( V s 3.2 km s‒1) at 15–30 km, which is considered a high-temperature partial melting magma, the crustal source of the hydrothermal active zone. We conclude that the hydrothermal system in this area can be divided into Batang-type and Kangding-type, both of which rely on a crustal heating cycle of atmospheric precipitation and surface water along the fracture zone. The heat is derived from the middle and lower crust: groundwater penetrates the deep faults bringing geothermal energy back to the surface and forming high-temperature springs.

Nanoscale zero-valent iron (nZVI) was prepared and used as a heterogeneous Fenton-like catalyst for the degradation of nuclear-grade cationic exchange resin. The properties of nZVI before and after reaction were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET) surface area analysis. The results showed that nZVI–H2O2 system exhibited the enhanced degradation of cationic resins, compared with Fe2+–H2O2, Cu0–H2O2, and Fe0/Cu0–H2O2 systems. The effects of initial temperature, nZVI dose, and H2O2 concentration were studied, and the higher temperature and nZVI dose with relatively low H2O2 concentration brought faster degradation rate. The degradation of cationic resins followed the pseudo-first-order kinetics with the apparent activation energy of 53.29 kJ/mol. According to the experimental and calculated infrared and UV-visible spectra, the carbon skeleton of cationic resins was broken with the detachment of benzene ring and the desulfonation of resin polymer by hydroxyl radicals (•OH), generating long-chain alkenes. These intermediates were further oxidized through the hydroxyl substitution, hydrogen abstraction, ring cleavage, or carbonylation reactions, finally forming carboxylic acids remained in solution.

Until recently, the characteristics of nano-microscale structures in the naturally deformed, overmature, marine shales were poorly known. Thermally overmature Lujiaping shales in the complex tectonic area of the northeast part of the upper Yangtze area, China have experienced strong tectonic deformation and are considered as potentially important strata for shale gas exploration. Naturally deformed samples from the main source rocks are selected from the Lower Cambrian Lujiaping Formation in the Dabashan Thrust-fold Belt to investigate nanometer- to micrometer-sized structures. A combination of scanning electron microscope (SEM), low-pressure nitrogen adsorption (LPNA), and low-field nuclear magnetic resonance (NMR) suggests that the pore types are dominantly fracture-related pores with a lesser abundance of mineral-hosted pores. These two pore types account for the 90% of total pore space. Organic matter (OM)-hosted pores are rare and make up a small part of the pore systems (less than 10%) due to high thermal maturity and intensive tectonic compression. Overall, the Lujiaping deformed, overmature samples have abundant nanometer- to micrometer-sized inorganic pores. High-resolution SEM images provide direct evidence of the formation of nano- and microsized structures such as OM&ndash, clay aggregates and silica nanograins. OM&ndash, clay aggregates are commonly observed in samples, which also exhibit abundant open microfractures and interparticle pores. Quartz can occur as silica nanograins and botryoids typically 20&ndash, 100 nm in size, which may influence porosity through the creation or occupying interparticle pore space.

International audience; The degradation pathway of the antibiotic metronidazole (MNZ) in wastewater was investigated computationally with a physical statistical method and a quantum chemical approach. In both cases, density functional theory (DFT) at the M06-2X/6-311+G(d,p) level was used to calculate the structures and property parameters of all molecules. On one hand, decay of the isolated MNZ molecule excited at a given excitation energy was studied using the statistical molecular fragmentation (SMF) model. On the other hand, the reaction mechanisms of MNZ oxidized by hydroxyl radicals (•OH) in advanced oxidation processes (AOPs) were analyzed. Both studies show that the main reaction sites in MNZ are, by decreasing importance, −NO2, −CH2OH, and −CH2CH2OH. The main degradation reactions are (i) alcohol group oxidation including the abstraction of hydrogen on C in the −CH2OH group and oxidation of the hydroxyl group to the aldehyde and further to the carboxylic acid and (ii) addition–elimination reactions happening on the imidazole ring which finally replace the nitro by hydroxyl radicals. The results gained are in a good agreement with the available experimental data on MNZ degradation by AOPs. The structures of intermediates, transition states, and free energy surfaces are helpful in elucidating the details of the elimination mechanism, supplementing current experimental knowledge.

Salvia species is a member of the Lamiaceae family, and it also possesses medicinal and horticulture values. The genetic diversity was assessed through sequence-related amplified polymorphism. To uncover genetic diversity and species characteristics in Salvia species were studied through a combination of morphological and molecular data. One hundred forty-five individuals related to 30 Salvia were collected in 18 provinces. A total of 157 (Number of total loci) (NTL) DNA bands were produced through polymerase chain reaction (PCR) from 30 Salvia species. These bands were produced with the combinations of 10 selective primers. The total number of amplified fragments ranged from 10 to 20. The predicted unbiased heterozygosity (H) varied between 0.11 (Salvia urmiensis) and 0.31 (Salvia limbata). High Shannon’s information index was detected in Salvia limbata. The genetic similarities between 30 species are estimated from 0.46 to 0.91. Clustering results showed two major clusters. According to the SRAP (Sequence-related amplified polymorphism) markers analysis, Salvia hydrangea and Salvia sharifii had the lowest similarity. Salvia bracteata and Salvia suffruticosa were genetically dissimilar to each other. This study also detected a significant signature of isolation by distance. Present results showed that sequence-related amplified polymorphism has the potential to decipher genetic affinity between Salvia species. Current results have implications in biodiversity and conservation programs. Besides this, present results could pave the way for selecting suitable ecotypes for forage and pasture purposes in Iran.

Fe-based heterogeneous Fenton-like catalysts has shown tremendous potential for wastewater treatment, but the investigation of adsorption, reduction and oxidation mechanism remains challenging. In this study, nanoscale zero-valent iron encapsulated in three-dimensional graphene network (3D-GN@nZVI) was synthesized and characterized as a heterogeneous Fenton-like catalyst via the activation of dissolved oxygen (DO) for adsorption and degradation of sulfadiazine (SDZ). 3D-GN@nZVI had the synergistic effect of catalytic reactivity for sulfadiazine removal, which was evaluated in view of the effects of operational factors. The role of adsorption, reduction and oxidation was determined; in 3D-GN@nZVI/DO system, sulfadiazine was removed mainly by the attack of hydroxyl radicals ( OH). The possible degradation pathway of sulfadiazine was inferred by identifying reactive oxidizing species and degradation intermediates. According to the X-ray photoelectron spectroscopy (XPS) analysis, Fourier Transform infrared spectroscopy (FTIR) analysis and density functional theory (DFT) calculations, the distribution and transfer of electrons on the surface of 3D-GN@nZVI were illustrated, and the adsorption and oxidation mechanisms of sulfadiazine through DO-driven and micro-electrolysis-enhanced heterogeneous Fenton-like reaction were proposed. The comprehensive mechanism was elucidated to provide new insights to advance the DO-driven Fenton-like process and to inspire the development of nZVI and relevant composites.