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Unlike modern Mn(IV)-dominated manganese nodules, ancient manganese deposits primarily contain Mn(II) (manganous) mineral phases. The general assumption is that these manganous minerals formed post-depositionally from a Mn(IV) precursor phase during diagenesis and metamorphism. However, recent studies have shown that aqueous Mn(II) may combine with either CO 3 2– (aq) or H 4 SiO 4(aq) to nucleate and precipitate as primary manganous phases within anoxic waters. These findings thus make it difficult to assess what comprised the primary mineral assemblage of ancient Mn deposits, which in turn, has implications for understanding the redox fabric of the past marine water column. Here, we investigate the paragenesis and oxidation state of various Mn minerals (oxides, carbonates, and silicates) from the late Devonian Xialei and middle to late Permian Zunyi manganese deposits in South China. Through characterization of the micro-scale distribution, composition, and speciation of different Mn-bearing mineral phases, we provide evidence to support an oxidative mechanism during Mn cycling at the time of deposition. We document the presence of a residual oxide phase (hausmannite; Mn 3 O 4) that represents a primary to early formed Mn(III)-bearing oxide preserved in Mn(II)-carbonate nodules. Additionally, we observe spherulitic textures comprised of mixed-valence Mn(II,III,IV)-silicates enclosed in diagenetic Mn(II)-carbonate laminations. Our results allow for the construction of a paragenetic model for these deposits beginning with the reduction of a primary Mn(IV) phase and the subsequent precipitation of intermediate Mn(III)-oxide or -silicate mineral phases. Following continued exposure to reducing conditions during early diagenesis, Mn(III)-oxides were then replaced by Mn(II)-carbonates. Similarly, Mn(III)-silicates were transformed into various Mn(II)-silicates during late-stage diagenesis and metamorphism. This model suggests that the accumulation of various divalent Mn mineral phases in ancient sediments may, therefore, be indicative of deposition under a water column with a sufficient oxidizing potential to induce Mn(II) oxidation. [ABSTRACT FROM AUTHOR]

Understanding the process of CO 2 degassing during precipitation of calcite from a Ca2+–HCO 3 − solution is crucial for interpreting isotope compositions in the calcite precipitates. Unlike diffusion-controlled outgassing, i.e., dissolved CO 2 escaping from the solution via diffusion, degassing caused by precipitation of calcite is accompanied by a large carbon isotope fractionation between CO 2 (g) and HCO 3 − due to breaking of C O bond, with an equilibrium fractionation of ca. −9‰ at ambient temperature. Such a magnitude of fractionation has a great influence on carbon isotope compositions (δ13C) of DIC (dissolved inorganic carbon) reservoir in the solution and thus on δ13C of calcite precipitated from it. However, knowledge on isotope fractionation is limited during precipitation-associated degassing of CO 2 in a supersaturated solution where rapid calcite precipitation drives CO 2 degassing out of isotopic equilibrium. Here we show the data of water chemistry and carbon isotope compositions of DIC and carbonate precipitates in a mountain stream at Baishuitai, China. Results from numerical models show there exist large degrees of carbon isotope disequilibrium during precipitation-associated degassing of CO 2 via HCO 3 − dehydration and dehydroxylation. Average carbon isotope fractionation between CO 2 (g) and HCO 3 − ( ε C O 2 (g) - HC O 3 - ) calculated from our dataset is about −20‰ which is much lower than the equilibrium value. Moreover, an inverse correlation between ε C O 2 (g) - HC O 3 - and precipitation rate was observed, indicating higher precipitation rates cause ε C O 2 (g) - HC O 3 - farther from equilibrium value. By compiling the data from this study and literatures, we infer that disequilibrium isotope fractionation of carbon between CO 2 (g) and HCO 3 − may be common during the growth of speleothem and travertine from a solution supersaturated with respect to calcite. The rate dependence of ε C O 2 (g) - HC O 3 - has special implications for speleothem archives from ventilated caves. As partial pressure of CO 2 in cave atmosphere evolves with ventilation, variable precipitation rates of calcite will cause inconstant degrees of disequilibrium isotope fractionation between CO 2 and DIC and thus perturb the time-series of speleothem's δ13C records for paleo-environmental reconstruction. [ABSTRACT FROM AUTHOR]

The aerosol scattering properties were investigated at two continental sites in northern China in 2004. Aerosol light scattering coefficient (σ sp) at 525nm, PM10, and aerosol mass scattering efficiencies (α) at Dunhuang had a mean value of 165.1±148.8Mm−1, 157.6±270.0μgm−3, and 2.30±3.41m2 g−1, respectively, while these values at Dongsheng were, respectively, 180.2±151.9Mm−1, 119.0±112.9μgm−3, and 1.87±1.41m2 g−1. There existed a seasonal variability of aerosol scattering properties. In spring, at Dunhuang PM10, σ sp, and α were 184.1±211.548μgm−3, 126.3±89.6Mm−1, and 1.05±0.97m2 g−1, respectively, and these values at Dongsheng were 146.4±142.1μgm−3, 183.4±81.7Mm−1, and 1.98±1.52m2 g−1, respectively. However, in winter at Dunhuang PM10, σ sp, and α were 158.1±261.4μgm−3, 303.3±165.2Mm−1, and 3.17±1.93m2 g−1, respectively, and these values at Dongsheng were 155.7±170.1μgm−3, 304.4±158.1Mm−1, and 2.90±1.72m2 g−1, respectively. σ sp and α in winter were higher than that in spring at both the sites, which coincides with the characteristics of dust aerosol and pollution aerosol. Overall, the dominant aerosol types in spring and winter at both sites in northern China are dust aerosol and pollution aerosol, respectively. [Copyright &y& Elsevier]

• Calcites precipitated from the solutions with identical chemical and isotopic compositions have different δ 13 C values. • The DBL thickness affects the pH and the δ 13 C value of HCO − 3 at the mineral-solution interface. • Our finding offers a mechanistic interpretation on the variability of the ε calcite / DIC in riverine or cave environments. It is often assumed that the carbon isotope composition (δ 13 C) of carbonate minerals records that of the dissolved inorganic carbon (DIC) species with insignificant disequilibrium effect. However, results from field observations and laboratory experiments have shown that the δ 13 C difference between calcite and solution can vary up to 3‰ even under a similar set of solution composition and temperature, raising uncertainties on the δ 13 C's paleoclimate and paleoecology implications. One likely cause is the variable calcite precipitation rates and pH values induced by different thicknesses of the stagnant liquid layer between solid and well mixed bulk solution (i.e., diffusion boundary layer, DBL). To test this hypothesis, we selected a well-studied natural travertine deposit (Baishuitai, SW China) which consists of meter-scale travertine terraces. Calcite crystals at both the pool bottom and the rim of the terraces are inorganically precipitated from solutions identical in chemical, isotopic composition and temperature, but different only in hydrodynamics. This difference results in thicker DBL for water at the pool-bottom than for water flowing across the rim. We found that the δ 13 C and Mg/Ca ratios are higher while Sr/Ca ratios are lower for the pool-bottom calcites than for the rim calcites. By applying a mass transfer model, we quantitatively link the differences in carbon isotope and elemental compositions of the abiogenic calcites to the different hydrodynamic conditions. The inverse variation in Mg/Ca and Sr/Ca ratios in calcites arises from the different precipitation rates between at the pool-bottom and at the rim, while the consistently lower δ 13 C for calcites at the rim is due to their higher pH at the solid-solution interface than for calcites precipitated at the pool-bottom. In contrast, calcite precipitation rate has little influence on carbon isotope fractionation between calcite and HCO − 3 . Our results demonstrate the role of DBL thickness in governing the δ 13 C of HCO − 3 at mineral surface, which can assist to interpret the variable δ 13 C values of calcites in riverine or cave environments. [ABSTRACT FROM AUTHOR]

As seagrasses are not available with commercial nursery stocks, the removal of a large amount of plant materials may damage donor populations. We evaluated the recovery of the eelgrass Zostera marina following the removal of entire plant patches (0.01–0.49 m2) at the edge and interior of an eelgrass bed in Rongcheng Bay, Shandong Peninsula, China, through a field experiment. We investigated the shoot density, morphology and growth of recovering plants following excavation. We found that the removal of entire small patches with excavation areas ≤0.25 m2 in the interior of the eelgrass bed was the most suitable strategy for harvesting donor plants of Z. marina. Small patch excavation (≤ 0.25 m2) was able to promote asexual reproduction in recovering plants, and their shoot density and morphology equaled or exceeded those of natural plants <7 months after harvesting. These results indicate that Z. marina plants have a strong capacity for resilience from physical disturbance through rhizome elongation in the harvested area. [ABSTRACT FROM AUTHOR]

The onset of the Middle Permian Emeishan Large Igneous Province (ELIP), is commonly implicated in the Guadalupian mass extinction, one of the largest Phanerozoic extinction events, yet the contribution of the ELIP to this biotic event remains unresolved because of a lack of appropriate age constraints. In this study, we examined claystone beds overlying the cherty limestone of the Maokou Formation and underlying the flood basalts of the ELIP that were emplaced around the Guadalupian-Lopingian Boundary. Integrated petrographic, mineralogical, elemental, and isotopic features indicate that the studied claystones contain significant components from mafic volcanic ash that was likely associated with the emplacement of the ELIP. Zircons from the claystones yield U Pb ages of ~262.5 Ma, which predates the subaerial eruptive phase of the ELIP (259.1–260.4 Ma), but is comparable to the J. altudaensis conodont biostratigraphic zone (~263 Ma, Middle Capitanian Stage) which is contemporaneous with the emplacement of early-stage Emeishan subaqueous pillow basalts and mafic volcaniclastics. Our data provide a crucial new constraint on the lower age limit for the onset of the ELIP, which was likely associated with violent submarine eruptions and thus could have contributed to the loss of marine fauna during the Guadalupian mass extinction. • The lower limit age for onset of the Emeishan Large Igneous Province (ELIP) is ~ 262.5 Ma • Mafic volcanism was likely associated with the emplacement of the ELIP. • Violent submarine eruptions contributed to the end-Guadalupian mass extinction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Five V-bearing minerals are identified in the Zhongcun deposit. • Mineralogy and trace element geochemistry studies indicate that the vanadium deposit in the Shuigoukou Formation precipitated under an anoxic environment. • Metal source for the vanadium deposits in southern Qinling was predominantly ambient seawater. • Vanadium mineralization processes underwent primarily sedimentary-diagenetic enrichment and, subsequently, hydrothermal overprinting. The formation of black shale-hosted vanadium deposits is controlled by several factors including metal supply, biological processes, and marine sedimentary environments. Vanadium-bearing minerals have a complex mineralogy in black shale-hosted vanadium deposits, and the implications for the mineralization processes are still poorly understood. This study investigated the mineralogy, rare earth, and trace element geochemistry of the early Cambrian black shale-hosted Zhongcun vanadium deposit in the southern Qinling area. Analytical results from the scanning electron microscope, laser Raman probe, and electron probe microanalysis reveal five V-bearing minerals in members I and II of the Zhongcun deposit, of which roscoelite is the dominant V-bearing mineral. Ore samples from members I and II of the Shuigoukou Formation have remarkably negative Ce anomalies, indicating that the surface water was oxic in the early Cambrian paleo-ocean in the southern Qingling area. Ni/Co, V/Cr, and Th/U ratios suggest that the vanadium ores formed in an anoxic environment, and Member II was more sulfidic than Member I. These features suggest a redox-stratified basin with a redox-variable sedimentary environment in the early Cambrian. The absence of Eu/Eu*-V correlation, and Y/Ho and Sm/Yb ratios indicate that vanadium was dominantly precipitated from ambient seawater and hydrothermal input was negligible. V-bearing minerals, including roscoelite, mannardite, and anatase, formed during late diagenesis. Subsequently, oxidized hydrothermal fluids overprinted previously formed V-bearing minerals and formed V-bearing goethite and sulvanite. [ABSTRACT FROM AUTHOR]

Energy has become a scarce global strategic resource, and energy supply security is receiving increasing attention. A common evaluation platform is necessary to systematically understand the supply security levels of different energy sources and help make the national energy strategy. Ecological network analysis (ENA) is thus regarded as a useful common tool to systematically simulate, evaluate, and compare the supply security for different energy sources, when considering the fact that modern energy systems have formed a complex global energy network through extensive energy trading. Based on the established ENA platform, we evaluated and compared China's crude oil and natural gas supply security from 2000 to 2012. To this end, we assessed the overall security level, investigated the relationship among different compartments within the network system, determined the system's structure, and analyzed the system's properties. It was found that the Chinese crude oil supply security level was higher than that of the natural gas supply and that the crude oil supply system was more mature in terms of multiple properties. Suggestions are proposed to improve the Chinese energy supply security based on further scenario analysis, including increasing domestic energy production, controlling energy consumption, diversifying foreign supply sources, and strengthening the strategic reserve. The ENA-based common platform can be used for the systematic evaluation and improvement of energy supply security and further support national energy policymaking for both developed and developing countries, both energy importers and exporters. [ABSTRACT FROM AUTHOR]

Sedimentary provenance in multiphase rift basins exhibits rapid variations during distinct tectonic sub-stages, and a close association exists between alterations in sediment source, geomorphology, and tectono-depositional records. This study comprehensively integrates sandstone petrology, heavy mineral assemblages, detrital zircon characters, drill cores, well logs, and seismic reflections to investigate the evolution of provenance and sedimentary records within a complete rifting episode in a lacustrine basin. Three tectono-depositional models for different tectonic sub-stages have been established. During the early strengthened stage of Rifting Episode IV (Sqd3), sediments were primarily sourced from the Liaoxi Uplift, serving as an intrabasinal provenance. These sediments mainly consist of medium-to coarse-grained sandstones with short-distance transportation, forming a transversely-sourced fan-delta and gravity-flow depositional system. Additionally, wedge-shaped seismic configurations were observed along the flow direction. In the middle stage of Rifting Episode IV (Sqd2), the Liaoxi Uplift was submerged, and sediments originated from the Qinhuangdao, Suizhong, and Liaodong Uplift regions. Lake basin expanded during this period, resulting in axially and transversely-sourced river deltaic deposits in a multi-stage superimposed manner, associated with gravity-flow deposits. The sediments are predominantly composed of medium-to fine-grained sandstones that underwent long-distance transportation, accompanied by a significant increase in mudstone content. Simultaneously, sigmoid-oblique and sigmoidal geometries extensively developed. During the late weakened stage of Rifting Episode IV (Sqd1), sediments originated from the Qinhuangdao and Suizhong regions, forming a transversely-sourced shoal-water deltaic system enriched in medium-to fine-grained sandstone with limited mudstone. In comparison to Sqd3 and Sqd2, sediments within Sqd1 underwent intermediate-distance transport. Typically, a shingled seismic configuration developed, presenting a sharp contrast with the sigmoid-oblique and sigmoidal reflections within Sqd2. The detailed models of source-to-sink systems developed in this study are expected to enhance the comprehensive understanding of sedimentological responses to provenance evolution across various tectonic sub-stages in lacustrine rift basins. • Geomorphology, provenance, and depositional architecture are closely linked to tectonic stage in lacustrine rift basins. • Modern topography and drainage systems aid in reconstructing ancient drainage systems and sediment supply capabilities. • Sandstone petrology, seismic data, zircon morphology and geochronology play pivotal roles in provenance assessment. • Detailed models of source-to-sink systems are built during various tectonic sub-stages in lacustrine rift basins. [ABSTRACT FROM AUTHOR]

Abstract: Travertine δ18O values can be used to reconstruct paleo-temperatures if the oxygen isotope fractionation factors between travertine and water are accurately understood. For this purpose, the δ18O values of pool travertine and its parent water, and the deposition rates of the calcite were investigated at Baishuitai (Yunnan, SW China) over the course of the full hydrological year, April 23 2006–April 25 2007. The results show that the travertine–water isotope fractionation factors are close to the commonly accepted equilibrium line of Kim and O’Neil (1997). This differs from the results obtained by Yan et al. (2012) who found that the oxygen isotope fractionation factors in the travertine-depositing pools were close to the line suggested as equilibrium relationship by Coplen (2007). The average calcite deposition rate (2.30mgcm−2 d−1) in the present study is six times larger than that (0.38mgcm−2 d−1) in Yan et al. (2012). If slower calcite precipitation leads to equilibrium oxygen isotopic fractionation, then the results of this study support the results of Coplen (2007) that indicate that the equilibrium fractionation factor may be greater than the commonly accepted one derived by Kim and O’Neil (1997). The relationship between oxygen isotope fractionation factor and calcite deposition rate in our study also agrees with the results of Dietzel et al. (2009) who found that the kinetic-isotope effect favors preferential incorporation of 16O in solid calcite as the calcite deposition rate increases. There was a threshold for calcite precipitation rate control on oxygen isotopic equilibrium. In our case of travertine-depositing pools, when the calcite deposition rate was lower than 0.38mgcm−2 d−1, oxygen isotopic equilibrium between calcite and water was attained. Therefore, calcite deposition rate is a potentially important consideration when using δ18O in natural carbonates as a proxy for terrestrial and ocean temperature. [Copyright &y& Elsevier]

δ13C and D14C measurements on dissolved inorganic carbon (DIC), particulate organic carbon (POC) and aquatic plants from a karst spring and two spring-fed ponds in Laqiao, Maolan Township, Libo County, southeastern Guizhou of China in January, July and October of 2013 have been carried out to understand the roles of aquatic photosynthesis through DIC uptake in surface karst waters. The mean D14C and δ13C values of DIC for the spring, midstream pond (MP) and downstream pond (DP) are −26 ± 36‰ and −13 ± 2‰, 6 ± 56‰ and −12 ± 3‰, and 0 ± 64‰ and −9 ± 2‰, respectively. The carbon source for the DIC is mainly from biogenic CO 2 rather than the dissolution of limestone rock as the D14C and δ13C of limestone are about −1000‰ and 2‰, respectively. The enrichment trend of D14C DIC and δ13C DIC from the spring to the DP indicates CO 2 exchange between atmospheric CO 2 and DIC, because D14C and δ13C values of atmospheric CO 2 are ca. 50‰ and −8‰, respectively. The average D14C POC values in the spring, MP and DP were −325‰, −123‰ and −158‰, respectively, which are all lower than these of the DIC in each reservoir. The lower D14C values of the POC may be caused by older soil carbon from surface runoff and dust fall. More aquatic algae were formed through photosynthesis in the stream ponds, especially in summer, shown by strongly increased D14C POC and evidence of growth in EDS/SEM analyses. Furthermore, the D14C values of the submerged aquatic plants range from −153‰ to −26‰, reflecting that the aquatic plants used DIC for photosynthesis. The D14C value of an emergent plant which uses atmospheric CO 2 during photosynthesis is 52.5 ± 0.3‰, equivalent to the atmospheric D14C. Seasonal variations of D14C DIC and δ13C DIC are influenced by soil CO 2 input, primary productivity in the ponds, and CO 2 exchange; hydrochemical condition show lower D14C values but higher δ13C values in cold/dry season, and vice versa in summer rainy season. A simple mass balance calculation indicates ~90% of carbon for the spring DIC is from biogenic CO 2 , with higher contribution in summer due to higher productivity. Although this simple calculation may overestimate the biogenic CO 2 , it indicates that organic decomposition is a major carbon source for DIC in the karst hydrological system. The results of the present study have implications for 14C dating on aquatic plant remains, regional and perhaps global carbon budgets, and the different behaviors of 13C and 14C in karst systems. • The DIC carbon source of the karst spring is mainly from biogenic CO2. • 13C and 14C tracing C source and transformation including photosynthesis CO 2 uptake • Aquatic plants uptake DIC CO 2 may cause an older 14C age. • Biological pump effect in terrestrial water can be an important natural carbon sink. [ABSTRACT FROM AUTHOR]

The ecological and environmental problems in the Yellow River Basin of northern China have attracted widespread research attention. This study focused on the soil heavy metals (HMs) in the middle Yellow River Basin; the spatial variations of soil HMs were analyzed using geostatistical techniques, the pollution status and health risks were comprehensively assessed through multiple methods, and the sources of soil HMs were apportioned using a positive matrix factorization (PMF) model. The results showed that the spatial patterns of soil HMs in the study area with a high coefficient of variation (>20 %) exhibited obvious regional zoning, at a low level in the north and a high level in the south. The soil with significantly high HM content was mainly located in the vicinity of industrial cities and usually featured large enrichment factor values (>1.5), especially with respect to Hg, Cd, and Pb, indicating some influence of anthropogenic activities on soil HMs. Based on the comprehensive assessment method, it was found that soil in the study area was clean and safe on the whole, but relatively severe pollution and relatively high risks were found in the strip area of urban agglomeration, including in Tongchuan and Weinan. Further, Hg, Cd, and Pb – with a cumulative contribution of >85 % – were the primary elements to cause soil pollution, while As and Pb were the primary objects leading to health risks, with a cumulative contribution of >95 %. After quantitative analysis using a PMF model, five sources of soil HMs were identified in the south and their contributions decreased in the following order: natural source (43.25 %), industrial source (21.09 %), mixed source (13.15 %), agricultural source (13.11 %) and traffic source (9.40 %). Moreover, some key areas were delineated both with the combined pollution of soil HMs and the relatively high health risk for children. These key areas should be paid more attention to and the Hg, Cd, Pb, and As should be the main objects of prevention and control in the middle Yellow River Basin. • Heavy metals pollution status in soil was evaluated in the middle Yellow River Basin. • Heavy metals showed the obvious spatial heterogeneity and regional zoning. • Human activity caused heavy metals enrichment/pollution near some industrial cities. • Five sources of soil heavy metals in the key area were identified by PMF model. • Hg, Cd, Pb, and As were diagnosed as the main objects of prevention and control. [ABSTRACT FROM AUTHOR]

Seagrass is an important foundational species in marine ecosystems that plays an important role in providing ecosystem services. However, seagrass distribution and suitable habitat have rapidly declined in recent decades because of climate change and human-mediated disturbances. To achieved better conservation and management of the seagrass Zostera marina , an important representative seagrass in northern China, studies must investigate how this species responds to climate change. Here, we used an ensemble species distribution model to forecast the potential distribution and future suitable habitat change for the eelgrass Z. marina in coastal areas of the Bohai Sea and Shandong Peninsula, China. Two future climate scenarios, RCP 4.5 and RCP 8.5, were considered, which represent stable and high levels of greenhouse gas emissions, respectively. The ensemble model accurately predicted the current Z. marina distribution and performed better than the single-algorithm methods of random forest, generalized boosting model and maximum entropy according to performance matrices (AUC and TSS). The distance to land (78.50 ± 3.51%) and the maximum sea surface temperature (11.90 ± 0.25%) were the most important variables determining the distribution of Z. marina , while the contributions of other variables, maximum sea surface current velocity (3.80 ± 0.33%), minimum surface salinity (2.15 ± 0.22%) and water depth (1.74 ± 0.24%) were relatively low. Under future climate scenarios, the suitable habitat of Z. marina was predicted to decrease by more than half by the 2050s, whereas under the pessimistic greenhouse gas emission scenario (RCP 8.5), suitable Z. marina habitat was predicted to decrease by nearly 80% by the end of this century. The loss of Z. marina seagrass beds will have important ecological effects on the marine ecosystem. Our results not only provide valuable information to assist in identifying potential Z. marina meadows, but also have important implications for guiding conservation and management of Z. marina in the northern coastal region of China. • The distribution and suitable habitat of Zostera marina was predicted under current conditions and future climate scenarios. • Ensemble model could accurately predict the present distribution of Zostera marina compare with single-algorithm models. • Climate change may lead to over 50% loss of the suitable habitat for Zostera marina in northern coastal areas of China. [ABSTRACT FROM AUTHOR]

The Belt and Road Initiative proposed by China is a common aspiration of all countries along their routes to achieve sustainable development of the environment, economy, society, and people's livelihood. Recently, prominently raised CO 2 concentration in the Belt and Road region is perceived to give rise to these serious greenhouse effects on severe and sustained global warming. It could lead to related climate instability, adverse natural disasters, glacier melting, and extreme weather patterns. CO 2 -enhanced oil recovery (CO 2 -EOR) is one of the essential CCU technologies. Due to lacking sustainable quantitative evaluation of CCU technology widely used in promising industries, it is imperative to conduct process simulation and optimization evaluation of CCU technology. Considering the lack of sustainable quantitative evaluation of CO 2 -EOR, we proposed a multi-objective optimization and sustainable quantitative assessment to provide insights and enhance the separation of produced gas and CO 2 capture for CO 2 -EOR. Their industrial applications before and after optimization were systematically simulated, discussed, and compared. With unremitting efforts, the optimized CO 2 capture process can stably separate oil field-produced gas into pure CO 2 and oilfield light hydrocarbons, with a mass content of CO 2 over 99.7 wt%. The optimized process demonstrated outstanding technical, economic, social, livelihood, and environmental properties. This study will undoubtedly benefit researchers in related fields of CCU process simulation, promote significant breakthroughs in basic research, superstructure, and commercial applications, and provide a perspective for the Belt and Road Initiative to establish better and optimize CCU devices and realize regional and global cooperation, future scientific and industrial progress. [Display omitted] • The first proposed simulation enhances the separation of produced gas and CO 2 capture for oil recovery. • Detailed process models, original simulation files, and detailed modeling steps are performed. • Life cycle optimization strategies using BAB methods are carried out from multi-dimension. • The optimized process has superior techno-economic-society-livelihood-environment property. [ABSTRACT FROM AUTHOR]

The Belt and Road Initiative proposed by China is a common aspiration of all countries along their routes to achieve sustainable development of the environment, economy, society, and people's livelihood. Recently, prominently raised CO 2 concentration in the Belt and Road region is perceived to give rise to these serious greenhouse effects on severe and sustained global warming. It could lead to related climate instability, adverse natural disasters, glacier melting, and extreme weather patterns. CO 2 -enhanced oil recovery (CO 2 -EOR) is one of the essential CCU technologies. Due to lacking sustainable quantitative evaluation of CCU technology widely used in promising industries, it is imperative to conduct process simulation and optimization evaluation of CCU technology. Considering the lack of sustainable quantitative evaluation of CO 2 -EOR, we proposed a multi-objective optimization and sustainable quantitative assessment to provide insights and enhance the separation of produced gas and CO 2 capture for CO 2 -EOR. Their industrial applications before and after optimization were systematically simulated, discussed, and compared. With unremitting efforts, the optimized CO 2 capture process can stably separate oil field-produced gas into pure CO 2 and oilfield light hydrocarbons, with a mass content of CO 2 over 99.7 wt%. The optimized process demonstrated outstanding technical, economic, social, livelihood, and environmental properties. This study will undoubtedly benefit researchers in related fields of CCU process simulation, promote significant breakthroughs in basic research, superstructure, and commercial applications, and provide a perspective for the Belt and Road Initiative to establish better and optimize CCU devices and realize regional and global cooperation, future scientific and industrial progress. [Display omitted] • The first proposed simulation enhances the separation of produced gas and CO 2 capture for oil recovery. • Detailed process models, original simulation files, and detailed modeling steps are performed. • Life cycle optimization strategies using BAB methods are carried out from multi-dimension. • The optimized process has superior techno-economic-society-livelihood-environment property. [ABSTRACT FROM AUTHOR]

Microbial activity has been proposed to play an important role in the genesis of manganese (Mn) carbonate deposition in natural sediments, with microbial reduction of Mn(IV) oxides as a crucial factor that enhances the saturation state of Mn carbonates in pore waters. Recently, the nucleation of Mn carbonates on cellular templates has been suggested to represent a further microbial control. However, microstructural evidence for this model remains tentative and the Mn carbonate nucleation pathway is still unconstrained. Here we report petrographic and in-situ chemistry that supports the direct role(s) of microbes in the formation of Mn carbonates in the giant Malkansu Mn metallogenic belt at West Kunlun, Northwest China. The Mn carbonate ores exhibit negative δ13C values (−10.2 to −12.7‰) that indicate the microbial reduction of Mn oxide. Microscopic data show that the Mn carbonates exhibit spheroidal rod and dumbbell-like shaped morphologies with a well-defined core-shell structure. These carbonates are intimately associated with net-like organic matter. An incubation experiment was also carried out showing that biogenic Mn carbonate minerals share a strikingly similar crystal form with the natural Mn ore samples. Together, these results provide further evidence for a dual role of microbes in Mn‑carbonate ore formation: Mn(II) and carbonate produced by the microbial reduction of Mn(IV) oxides, and the nucleation of Mn carbonate minerals on cellular surfaces and/or organic matrices. Potentially, these Mn carbonates may have self-assembled to form rod- and dumbbell-like shaped morphologies, analogous to other carbonate systems. The unique core-shell structure observed herein also indicates that the formation of Mn‑carbonates mediated by microbes follows a heterogeneous nucleation pathway. [ABSTRACT FROM AUTHOR]

Oridonin is a diterpenoid isolated from Rabdosia rubescens (Hemsl.) Hara, a well-known herbal tea in China with many health benefits. To provide a better understanding of the potential cardioprotective effect of Oridonin, we investigated the metabolic alterations in heart tissue and serum of rat subjected to myocardial ischemia/reperfusion (MI/R) injury with or without pretreatment of Oridonin by UPLC-MS/MS metabolomics approach. Rats were randomly divided into groups as follows: Control, Sham, MI/R and pretreated with Oridonin (10 mg/kg)+MI/R. After 24 h of reperfusion, heart tissue and serum were collected for biochemical and metabolomic analysis. Pretreatment with Oridonin significantly decreased infarct size and reversed the abnormal elevated myocardial zymogram in serum. Moreover, Oridonin regulated several metabolic pathways, including glycolysis, branched chain amino acid, kynurenine, arginine, glutamine and bile acid metabolism. Our results suggest that Oridonin indeed displays outstanding cardioprotective effect mainly by regulating energy and amino acid metabolism. Scheme summarizing the potential mechanisms of Oridonin against MI/R injury by regulating several host metabolic pathways, including glycolysis, branched chain amino acid, kynurenine, arginine and bile acid metabolism. Image 1 [ABSTRACT FROM AUTHOR]