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In this paper, an improved YOLOv5 multiscale marine organism target detection algorithm (YOLOv5‐Mult) is proposed to address the insufficient feature extraction ability of small targets, low detection accuracy, and high catching error of existing models in complex environments. First, real frame clustering is performed using the Kmeans++ method. Second, the BiFPN network module is adopted in lieu of the PANet network module to enhance the feature fusion ability. Next, the multilayer semantic fusion module RBC (RepBlock CSP) replaces the C3 module before the SPP layer of the Backbone network and the C3 module in the Neck layer to enrich the image semantic information. Finally, the multiscale feature fusion module MC (Mult Conv) replaces the last C3 module in the Backbone network to mitigate the semantic gap between different feature channel layers. Experimental results demonstrate that the improved algorithm attains a mAP value of 71.18%, which is 5.22% higher than that of the original YOLOv5 algorithm, providing accurate identification and fishing for underwater robots. [ABSTRACT FROM AUTHOR]

The electronic and photophysical properties for a series of ruthenium(II) polypyridyl dyes are presented where a π‐accepting 5‐(vinyl‐cyanine)‐8‐oxyquinolate class of ligand is incorporated to yield an improved vis–NIR absorption. A combination of computational, UV–vis–NIR absorption, phosphorescence emission and cyclic voltammetry studies are used to probe the influence of these ligands on complex electronic and photophysical properties. To assess their potential as vis–NIR photoacoustic contrast agents, select complexes were formulated in a PBS buffer/Tween® 20 solvent system. The p‐quinolin‐1‐ium, 1,3,3‐trimethyl‐3H‐indol‐1‐ium and 1,1,3‐trimethyl‐1H‐benzo[e]indol‐3‐ium acceptor groups each impart a strong 680 nm optical absorption and photoacoustic emission on par with the performance exhibited by both the methylene blue and cryptocyanine commercial dyes. [ABSTRACT FROM AUTHOR]

The electronic and photophysical properties for a series of ruthenium(II) polypyridyl dyes are presented where a π‐accepting 5‐(vinyl‐cyanine)‐8‐oxyquinolate class of ligand is incorporated to yield an improved vis–NIR absorption. A combination of computational, UV–vis–NIR absorption, phosphorescence emission and cyclic voltammetry studies are used to probe the influence of these ligands on complex electronic and photophysical properties. To assess their potential as vis–NIR photoacoustic contrast agents, select complexes were formulated in a PBS buffer/Tween® 20 solvent system. The p‐quinolin‐1‐ium, 1,3,3‐trimethyl‐3H‐indol‐1‐ium and 1,1,3‐trimethyl‐1H‐benzo[e]indol‐3‐ium acceptor groups each impart a strong 680 nm optical absorption and photoacoustic emission on par with the performance exhibited by both the methylene blue and cryptocyanine commercial dyes. [ABSTRACT FROM AUTHOR]

A series of aminopyrazine derivatives were designed and synthesized for the development of effective inhibitors for Q235 steel corrosion in 1.0 M HCl solution, in which the monohalogenated aminopyrazine showed good inhibitive performance. The corrosion protection properties of the monohalogenated aminopyrazine, including 2‐amino‐5‐chloropyrazine (ACP), 2‐amino‐5‐bromopyrazine (ABP), and 2‐amino‐5‐iodopyrazine (AIP), were further investigated using weight‐loss test and electrochemical techniques. The results indicated the halogen‐substituted aminopyrazine have excellent inhibition performance, and these aminopyrazine derivatives act as mixed type inhibitors with predominant cathodic effectiveness. Adsorption of halogen‐substituted aminopyrazine on steel surface obeyed the Langmuir adsorption isotherm. The adsorption of the inhibitor molecules on steel surface was further supported by scanning electron microscope (SEM). The inhibition mechanism of the investigated monohalogenated aminopyrazine was derived using density functional theory (DFT) based quantum chemical calculations for their neutral as well as protonated forms. Both experimental and DFT studies suggested that the inhibition efficiency of three halogen‐substituted aminopyrazine followed the order of η(AIP)>η(ABP)>η(ACP). [ABSTRACT FROM AUTHOR]

Accurate predictions of the air quality index (AQI) is critical for pollution control and air quality warning. However, this is challenging because of the nonlinearity of data and the uncertainty between data relationships. This paper proposes a combinatorial model based on an improved adaptive dynamic particle swarm optimization (ADPSO) algorithm to optimize a bidirectional gated recurrent unit (BiGRU) neural network to predict AQI time series and capture data dependence. The ADPSO method incorporates a dynamic spatial search strategy into the standard particle swarm optimization method, allowing the parameters to be dynamically adjusted to balance global and local search capabilities, thus improving the performance and effectiveness of this optimization process. Compared to the BiGRU model, the PSO‐BiGRU model, and the radial basis neural,the results of the improved algorithm reveal that the root mean square error (RMSE), mean absolute error (MAE), and mean absolute percentage error (MAPE) of the ADPSO‐BiGRU predicted air pollution index are smaller than the errors of the other three models. The accuracy of the ADPSO‐BiGRU prediction model is higher than that of the other models, and it aids in the development of effective regional air quality management policies to reduce the negative impacts of pollution. [ABSTRACT FROM AUTHOR]

Microfractures in the coal matrix have complex spatial structure because of the joint effects of coalification and tectonism. The accurate modeling and characterization of microfractures directly affect mechanism analysis of coal rock fracturing and mining. In this study, taking the high‐rank coal in the north of Qinshui Basin, structural characteristics of microfracture in intact and tectonic coals were analyzed systematically using 2D thin section, 3D micro‐CT modeling and mercury intrusion based on digital image analysis and fractal theory. The result indicates that the response sensitivity of fractal parameters obtained from different methods to microfractures from two types of coal structures is different greatly. Single fractal dimension (Df) in tectonic coal is higher than that of intact coal. Specially, for 2D thin sections, the indicative effect on the Df of manually corrected images is better than that of automatically extracted and linear ones. Df has a positive correlation with the pixel‐based microfracture porosity, as well as generalized fractal parameters. Moreover, microfracture permeability based on the Cubic‐Law increases with the increase of Df. For 3D micro‐CT modeling, the classical Watershed algorithm cannot segment the spatial microfracture network, which, however, can be segmented and characterized by the self‐developed FracSC3D program. Spatial microstructural parameters including volume, surface and length at three‐axis directions meet bifractal characteristics. Specially, for 2D micro‐CT slices, with the increase of porosity, the multifractal spectrum width Δα also increased. Besides, the fractal parameter based on Menger model from mercury intrusion experiment can act as a good indicator for identifying microfractures, flow pores and diffusion pores. Key Points: 3D microfracture network is segmented and characterized by the developed algorithm FracSC3DClassical watershed algorithm used to segment pore bodies in porous media cannot be used to segment 3D fracture surfaces in fractured media3D microfracture characteristic parameters and mercury intrusion porosimetry meet the dual fractal scaling rather than single fractal law [ABSTRACT FROM AUTHOR]

Machine learning (ML) integrated with density functional theory (DFT) calculations have recently been used to accelerate the design and discovery of single‐atom catalysts (SACs) by establishing deep structure–activity relationships. The traditional ML models are always difficult to identify the structural differences among the single‐atom systems with different modification methods, leading to the limitation of the potential application range. Aiming to the structural properties of several typical two‐dimensional MA2Z4‐based single‐atom systems (bare MA2Z4 and metal single‐atom doped/supported MA2Z4), an improved crystal graph convolutional neural network (CGCNN) classification model was employed, instead of the traditional machine learning regression model, to address the challenge of incompatibility in the studied systems. The CGCNN model was optimized using crystal graph representation in which the geometric configuration was divided into active layer, surface layer, and bulk layer (ASB‐GCNN). Through ML and DFT calculations, five potential single‐atom hydrogen evolution reaction (HER) catalysts were screened from chemical space of 600 MA2Z4‐based materials, especially V1/HfSn2N4(S) with high stability and activity (ΔGH* is 0.06 eV). Further projected density of states (pDOS) analysis in combination with the wave function analysis of the SAC‐H bond revealed that the SAC‐dz2 orbital coincided with the H‐s orbital around the energy level of −2.50 eV, and orbital analysis confirmed the formation of σ bonds. This study provides an efficient multistep screening design framework of metal single‐atom catalyst for HER systems with similar two‐dimensional supports but different geometric configurations. [ABSTRACT FROM AUTHOR]

Anionic redox chemistry has aroused increasing attention in sodium‐ion batteries (SIBs) by virtue of the appealing additional capacity. However, up to now, anionic redox reaction has not been reported in the mainstream phosphate cathodes for SIBs. Herein, the ultrathin VOPO4 nanosheets are fabricated as promising cathodes for SIBs, where the oxygen redox reaction is first activated accompanied by reversible ClO4− (from the electrolyte) insertion/extraction. As a result, the VOPO4 cathode harvests a record‐high capacity (168 mAh g−1 at 0.1 C) among its counterparts ever reported. Moreover, the ClO4− insertion efficiently expands the interlayer spacing of VOPO4 and accelerates the ion diffusion, enabling an unprecedentedly high rate performance (69 mAh g−1 at 30 C). Via systematic ex situ characterizations and theoretical computations, the anionic redox chemistry and charge storage mechanism upon cycling are thoroughly elucidated. This study opens up a new avenue toward high‐energy phosphate cathodes for SIBs by triggering anionic redox reactions. [ABSTRACT FROM AUTHOR]

Layered V2O5 is a star cathode material of rechargeable aqueous zinc‐based batteries (RAZBs) owing to the rich redox chemistry of vanadium, which commonly exhibits the 2D ion‐diffusion mechanism through Zn2+ (de)intercalation at edge sites but is plagued by the inert basal planes. Here, hierarchically porous V2O5 nanosheets vertically grown on carbon cloth (V2O5/C) are innovatively prepared, where the porous structure with lattice defects successfully unlocks the V2O5 basal plane to provide additional ion‐diffusion channels and abundant active sites. Thus, highly efficient and ultrafast 3D Li+/Zn2+ co‐insertion/extraction behaviors along both the c‐axis and ab plane of V2O5 are realized for the first time in the formulated 15 m LiTFSI + 1 m Zn(CF3SO3)2 aqueous electrolyte, as elucidated by systematic ex situ analyses, multiple electrochemical measurements, and theoretical computations. As a result, the porous V2O5/C electrode delivers an exceptional high‐rate capability (up to 100 A g−1) and an ultralong cycling durability (15 000 cycles) in RAZBs. Finally, quasi‐solid‐state wearable rechargeable zinc batteries employing the porous V2O5/C cathode demonstrate respectable performance even under severe deformations and low temperatures. This work achieves a conceptual breakthrough represented by an upgrading of the traditional 2D ion transportation in layered cathodes to the more facile 3D diffusion for designing high‐performance battery electrochemistry. [ABSTRACT FROM AUTHOR]

In this paper, the Delayed Detached‐Eddy Simulation (DDES) model is used to simulate the cloud cavitation process and the flow field distribution characteristics in the three‐dimensional cavitating chamber with a sudden change channel. The effect of cavitation evolution on the flow field is investigated by the change of vacuole volume fraction and the distribution of physical quantities in the flow field. And the Q criterion is introduced to identify the vortex structure and its variation. The results show that the evolution of cavitation presents periodic characteristics, but in a period, the flow field distribution, vortex structure, and vortex intensity under different cavitation states are different. In the stage of bubble growth, falling off, bubble cluster breaking, and separation, the vortex size is large and the vortex intensity is high, making the flow field show drastic fluctuations. However, in the stage of bubble mass integration, the flow field fluctuation is relatively weak, and the pressure fluctuation law is consistent with the bubble shedding frequency. In addition, the Q criterion indicates that the high‐strength vortices are mainly concentrated in the throat, as the degree of cavitation increases, vortex breakage is intensified and vortices are not obvious in the flow field. [ABSTRACT FROM AUTHOR]

Soil microbial biomass and microbial stoichiometric ratios are important for understanding carbon and nutrient cycling in terrestrial ecosystems. Here, we compiled data from 12245 observations of soil microbial biomass from 1626 published studies to map global patterns of microbial biomass carbon (MBC), microbial biomass nitrogen (MBN), microbial biomass phosphorus (MBP), and their stoichiometry using a random forest model. Concentrations of MBC, MBN, and MBP were most closely linked to soil organic carbon, while climatic factors were most important for stoichiometry in microbial biomass ratios. Modeled seasonal MBC concentrations peaked in summer in tundra and in boreal forests, but in autumn in subtropical and in tropical biomes. The global mean MBC/MBN, MBC/MBP, and MBN/MBP ratios were estimated to be 10, 48, and 6.7, respectively, at 0–30 cm soil depth. The highest concentrations, stocks, and microbial C/N/P ratios were found at high latitudes in tundra and boreal forests, probably due to the higher soil organic matter content, greater fungal abundance, and lower nutrient availability in colder than in warmer biomes. At 30–100 cm soil depth, concentrations of MBC, MBN, and MBP were highest in temperate forests. The MBC/MBP ratio showed greater flexibility at the global scale than did the MBC/MBN ratio, possibly reflecting physiological adaptations and microbial community shifts with latitude. The results of this study are important for understanding C, N, and P cycling at the global scale, as well as for developing soil C‐cycling models including soil microbial C, N, and P as important parameters. [ABSTRACT FROM AUTHOR]

In this paper, a novel energy storage technology of a gravity‐enhanced compressed air energy storage system is proposed for the first time, aiming to support the rapid growth of solar and wind capacity. With air storage formed by the shaft well, gravity piston, and seal membrane, the proposed system could achieve constant operating pressure, high storage efficiency, and large storage capacity. Electricity charged into this system is simultaneously transformed and stored in the thermal, pressure potential, and gravitational potential forms. The operating properties of the proposed system are simulated and analyzed with the commercial software Thermoflex V29. Results show that both the storage pressure and the well radius have essential influences on the performance of the newly proposed system. The theoretical energy storage efficiency of the proposed system is in a scope of 63.58%–65.50% with a storage pressure range of 40–100 bar. Economic analysis based on the time‐of‐use price policy in China suggests that the optimum levelized cost of storage (LCOS) happens at the storage pressure of 70 bar and a well radius of 8 m. Besides, considering different plant cost factors that reflect the total investment of a power plant, the optimum LCOS is 1.09–1.26 CNY/kWh. Moreover, the specific exergy cost of the discharged electricity is assessed to be 0.51 CNY/kWh or so, which is significantly more profitable compared with the given electricity price of 1.15 CNY/kWh at off‐peak. [ABSTRACT FROM AUTHOR]

Fine‐tuning the interior structure of porous materials is desirable for altering the gas transport characteristic. An activation‐induced structure manipulation strategy is reported here to act on ZIF‐8 membranes for C3H6/C3H8 separation. Notably, after treatment with methanol, acetonitrile and chloroform, the amount of embedded N,N‐dimethylacetamide (DMAc) molecules within ZIF‐8 cavity is about 0.8, 1.2 and 3.8 molecules per cage, respectively. The increased amount of DMAc results in enhanced thermodynamic adsorption selectivity of ZIF‐8 for C3H6/C3H8, which is highly constructive to the separation ability of corresponding ZIF‐8 membranes. Typically, the ZIF‐8 membranes activated with methanol, acetonitrile and chloroform demonstrate C3H6 permeance of 1.5 · 10−8, 8.5 · 10−9 and 4.3 · 10−9 mol m−2s−1Pa−1, and C3H6/C3H8 separation factors of 52, 92 and 192, respectively. [ABSTRACT FROM AUTHOR]

Triggering the anionic redox chemistry in layered oxide cathodes has emerged as a paradigmatic approach to efficaciously boost the energy density of sodium‐ion batteries. However, their practical applications are still plagued by irreversible lattice oxygen release and deleterious structure distortion. Herein, a novel P2‐Na0.76Ca0.05[Ni0.23□0.08Mn0.69]O2 cathode material featuring joint cationic and anionic redox activities, where native vacancies are produced in the transition‐metal (TM) layers and Ca ions are riveted in the Na layers, is developed. Random vacancies in the TM sites induce the emergence of nonbonding O 2p orbitals to activate anionic redox, which is confirmed by systematic electrochemical measurements, ex situ X‐ray photoelectron spectroscopy, in situ X‐ray diffraction, and density functional theory computations. Benefiting from the pinned Ca ions in the Na sites, a robust layered structure with the suppressed P2‐O2 phase transition and enhanced anionic redox reversibility upon charge/discharge is achieved. Therefore, the electrode displays exceptional rate capability (153.9 mA h g−1 at 0.1 C with 74.6 mA h g−1 at 20 C) and improved cycling life (87.1% capacity retention at 0.1 C after 50 cycles). This study provides new opportunities for designing high‐energy‐density and high‐stability layered sodium oxide cathodes by tuning local chemical environments. [ABSTRACT FROM AUTHOR]

In agro‐ecosystems, fertilization practices must accomplish high and stable crop productivity, with maximum soil organic carbon (SOC) sequestration to address climate change and food security challenges. However, the impacts of these practices on SOC and crop yields are variable over the long‐term duration, and an improved understanding of the factors influencing SOC sequestration and sustainable productivity is still needed to provide evidence‐based management decisions. Therefore, we conducted a meta‐analysis to evaluate the impact of long‐term (≥10 years) application of different fertilizer management practices adapted across China on crop productivity, yield sustainability, and SOC sequestration. Results indicated that unbalanced mineral fertilizer (UMF), balanced mineral fertilizer (BMF), organic fertilizers (OF), combined unbalanced mineral and OF, and combined balanced mineral and organic fertilizers (BMOF) significantly enhanced the grain yield, and SOC sequestration compared with control (p <.05). For UMF, the increases in SOC and grain yields were least among fertilization practices. Comparing OF, BMF mostly produced more grain yields, but with a slight increase in C sequestration. Highest SOC sequestration rate of 0.43 Mg C ha−1 yr−1 was recorded in BMOF, among all the treatments. The data obtained indicated that SOC sequestration is highly time‐dependent. Irrespective of fertilization mode, SOC gradually increased and attained the peak of sequestration rate in the initial two decades rather than at later stages of fertilizer addition. The linear fitted model indicated that an increase in SOC sequestration benefits sustainable productivity. The available data indicate that crop yields can be improved by 143 kg ha−1 for rice (Oryza sativa), 255 kg ha−1 for maize (Zea mays), and 202 kg ha−1 for wheat (Triticum aestivum) with every 1 Mg ha−1 increase in SOC stock by fertilization in the root zone. In crux, BMOF can maintain and improve soil quality while producing high and stable crop yields. [ABSTRACT FROM AUTHOR]

Summary: Taxonomic relations play an important role in various Natural Language Processing (NLP) tasks (eg, information extraction, question answering and knowledge inference). Existing approaches on embedding‐based taxonomic relation learning mainly rely on the word embeddings trained using co‐occurrence‐based similarity learning. However, the performance of these approaches is not quite satisfactory due to the lack of sufficient taxonomic semantic knowledge within word embeddings. To solve this problem, we propose an improved embedding‐based approach to learn taxonomic relations via incorporating relation descriptions into word embeddings. First, to capture additional taxonomic semantic knowledge, we train special word embeddings using not only co‐occurrence information of words but also relation descriptions (eg, taxonomic seed relations and their contextual triples). Then, using the trained word embeddings as features, we employ two learning models to identify and predict taxonomic relations, namely, offset‐based classification model and offset‐based similarity model. Experimental results on four real‐world domain datasets demonstrate that our proposed approach can capture additional taxonomic semantic knowledge and reduce dependence on the training dataset, outperforming the state‐of‐the‐art compared approaches on the taxonomic relation learning task. [ABSTRACT FROM AUTHOR]

Abstract: The Zhaxikang Pb‐Zn‐Ag‐Sb deposit, the largest polymetallic deposit known in the Himalayan Orogen of southern Tibet, is characterized by vein‐type mineralization that hosts multiple mineral assemblages and complicated metal associations. The deposit consists of at least six steeply dipping vein‐type orebodies that are hosted by Early Jurassic black carbonaceous slates and are controlled by a Cenozoic N–S‐striking normal fault system. This deposit records multiple stages of mineralization that include an early period (A) of massive coarse‐grained galena–sphalerite deposition and a later period (B) of Sb‐bearing vein‐type mineralization. Period A is only associated with galena–sphalerite mineralization, whereas period B can be subdivided into ferrous rhodochrosite–sphalerite–pyrite, quartz–sulfosalt–sphalerite, calcite–pyrite, quartz–stibnite, and quartz‐only stages of mineralization. The formation of brecciated galena and sphalerite ores during period A implies reworking of pre‐existing Pb–Zn sulfides by Cenozoic tectonic deformation, whereas period B mineralization records extensive open‐space filling during ore formation. Fluid inclusion microthermometric data indicate that both periods A and B were associated with low–medium temperature (187–267°C) and low salinity (4.00–10.18% wt. NaCl equivalent) ore‐forming fluids, although variations in the physical–chemical nature of the period B fluids suggest that this phase of mineralization was characterized by variable water/rock ratios. Microprobe analyses indicate that Fe concentrations in sphalerite decrease from period A to period B, and can be divided into three groups with FeS concentrations of 8.999–9.577, 7.125–9.109, 5.438–1.460 mol.%. The concentrations of Zn, Sb, Pb, and Ag within orebodies in the study area are normally distributed in both lateral and vertical directions, and Pb, Sb, and/or Ag concentrations are positive correlation within the central part of these orebodies, but negatively correlate in the margins. Sulfide S isotope compositions are highly variable (4‰–13‰), varying from 4‰ to 11‰ in period A and 10‰ to 13‰ in period B. The Pb isotope within these samples is highly radiogenic and defines linear trends in 206Pb/204Pb vs. 207Pb/204Pb and 206Pb/204Pb vs. 208Pb/204Pb diagrams, respectively. The S and Pb isotopic characteristics indicate that the period B orebodies formed by mixing of Pb–Zn sulfides and regional Sb‐bearing fluids. These features are indicative of overprinting and remobilization of pre‐existing Pb–Zn sulfides by Sb‐bearing ore‐forming fluids during a post‐collisional period of the Himalayan Orogeny. The presence of similar ore types in the north Rhenish Massif that formed after the Variscan Orogeny suggests that Zhaxikang‐style mineralization may be present in other orogenic belts, suggesting that this deposit may guide Pb–Zn exploration in these areas. [ABSTRACT FROM AUTHOR]

Abstract: The Yangbishan iron–tungsten deposit in the Shuangyashan area of Heilongjiang Province is located in the center of the Jiamusi Massif in northeastern China. The rare earth element and trace element compositions of the scheelite show that it formed in a reducing environment and inherited the rare earth element features of the ore‐forming fluid. The geochemical characteristics of the gneissic granite associated with the tungsten mineralization show that the magma formed in this reducing environment and originated from the partial melting of metamorphosed shale that contained organic carbon and was enriched with tungsten. In addition, in situ Hf isotopic analysis of zircons from the gneissic granite indicates that they probably originated from the partial melting of a predominantly Paleo–Mesoproterozoic crustal source. According to LA‐ICP‐MS zircon dating, the Yangbishan ore‐related gneissic granite has an Early Paleozoic crystallization age of 520.6 ± 2.8 Ma. This study, together with previous data, indicates that the massifs of northeastern China, including Erguna, Xing'an, Songliao, Jiamusi, and Khanka massifs, belonged to an orogenic belt that existed along the southern margin of the Siberian Craton during the late Pan‐African period. The significant continental movements of this orogeny resulted in widespread magmatic activity in northeastern China from 530 Ma to 470 Ma under a tectonic setting that transitioned from compressional syn‐collision to extensional post‐collision. [ABSTRACT FROM AUTHOR]

The rare earth elements (REE) composition of the polymetallic crusts and nodules obtained from the South China Sea (SCS) were analyzed through inductively coupled plasma mass spectrometry. Results revealed great differences in the REE abundances (ΣREE) of the SCS polymetallic crusts and nodules; the crusts show the highest ΣREE, whereas the nodules exhibit the lowest ΣREE. The similarity in their NASC-normalized patterns, the enriched light REE (LREE), the markedly positive Ce anomaly ( δCe), and the non- or weakly positive Eu anomaly ( δEu), suggest that the polymetallic crusts and nodules are of hydrogenetic origin. Moreover, the REE contents and their relevant parameters are quite different among the various layers of the crusts and nodules, which probably results from the different marginal sea environments and mineral assemblages of the samples. The growth profiles of the SCS polymetallic crusts and nodules reveal the tendency ΣREE and δCe to slightly increase from the outer to the inner layers, suggesting that the growth environments of these samples changed smoothly from an oxidizing to a relatively reducing environment; in addition, the crust ST1 may have experienced a regressive event (sea-level change) during its growth, although the REE composition of the seawater remained relatively stable. On the basis of the regional ΣREE distribution in the SCS crusts and nodules, the samples collected near the northern margin were influenced by terrigenous material more strongly compared with the other samples, and the REE contents are relatively low. Therefore, the special geotectonic environment is a significant factor influencing the abundance of elements, including REE and other trace elements. Compared with the oceanic seamount crusts and deep-sea nodules from other oceans, the SCS polymetallic crusts and nodules exhibit special REE compositions and shale-normalized patterns, implying that the samples are of marginal sea-type Fe-Mn sedimentary deposits, which are strongly affected by the epicontinental environment, and that they grew in a more oxidative seawater environment. This analysis indicates that the oxidized seawater environment and the special nano property of their Fe-Mn minerals enrich the REE adsorption. [ABSTRACT FROM AUTHOR]

ABSTRACT Land-use and land-cover change ( LUCC, such as the conversion of natural landscape to agricultural land) and human activities ( HAs) are the most important human influences ( HIs) on regional climate. Studying such influences is fundamental to understanding anthropogenic climate change. Our objectives were to quantify contributions of HI on regional temperature change and demonstrate that HI may cause abrupt climate change. We quantified the contribution of HI on regional temperature by comparing the seasonal temperature changes between a human-dominated plain and an adjoining natural plain using the daily maximum ( Tmax) and minimum ( Tmin) temperature data from 12 meteorological stations. We quantified the contribution of HA on regional temperature change using winter weather data because snow cover in both plains masked the effects of LUCC. HI caused decreases in Tmax and increases in Tmin, and an increase in mean temperature. HA contributed to the reduction in the diurnal temperature range, whereas LUCC caused an increase in the range. The abrupt temperature change was in accord with the abrupt changes in agricultural land area and population. The HI led to an abrupt change in Tmax 3 years earlier (1985) than the recognized abrupt climate change in the Northern Hemisphere (1988). The synthetic effects of HI ( LUCC and HA) evidently altered the change trends and accelerated abrupt changes in regional temperature, which affected the regional climate. Our findings can elucidate regional climate patterns and improve the accuracy of downscaling general circulation models. [ABSTRACT FROM AUTHOR]

Outcrop and drill hole data show that the Jurassic coal measures in the northeastern Ordos Basin are composed mainly of the Yan'an Formation and the lowstand system tract of the Zhiluo Formation, and there is a regional unconformity between them. The Dongsheng uranium deposit is associated with the Jurassic coal measures. Research data indicate that the Jurassic coal measures in the study area have a certain hydrocarbon-generating capacity, although the metamorphic grade is low ( Ro=0.40%-0.58%). In the Dongsheng region alone, the accumulative amount of generated coalbed methane (CBM) is about 2028.29 × 108 −2218.72 × 108 m3; the residual amount is about 50.92 × 108 m3, and the lost amount is about 1977 × 108 m3. Analysis of the burial history of the host rocks and the evolutionary history of the Dongsheng uranium deposit suggests that the Jurassic coal measures generated hydrocarbon mainly from Middle Jurassic to Early Crataceous, which is the main mineralization phase of the Dongsheng uranium deposit. By the Late Cretaceous, a mass of CBM dissipated due to the strong tectonic uplift, and the Dongsheng uranium deposit stepped into the preservation phase. Therefore, the low-mature hydrocarbon-containing fluid in the Jurassic coal measures not only served as a reducing agent for the formation of sandstone-type uranium deposits, but also rendered the second reduction of paleo-interlayer oxidation zone and become the primary reducing agent for ore conservation. Regional strata correlation reveals that the sandstone-type uranium reservoir at the bottom of the Zhiluo Formation is in contact with the underlying industrial coal seams in the Yan'an Formation through incision or in the form of an unconformity surface. In the Dongsheng region with poorly developed fault systems, the unconformity surface and scour surface served as the main migration pathways for low-mature hydrocarbon-containing fluid migrating to the uranium reservoir. [ABSTRACT FROM AUTHOR]

The article presents abstracts on geological topics which include the geochemistry of zircon in Yunnan, China, mineral quartz in polymetallic deposits in Gacun, China, and the interaction between water and syenite at different temperatures.