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China is a large rare earth country that has pushed for related rare earth research, development, and application in the global development and progress of rare earths. The rare earth resource reserve strategy must be implemented by China due to the situation of rare earth resources at home and abroad, national security, and the need to strengthen the right to speak in the international market. This article builds the rare earth mineral resources reserve system and model from the perspective of regional development and uses the improved SURF algorithm to solve the problems of inaccurate mine location, mine location deviation, dislocation, overlap, and other issues, resulting in more accurate mineral resources reserve management data. The results show that the maximum relative error between the parallel profile method and the traditional method is 2.6%, which meets the requirement for mineral reserve calculation accuracy and can be used to calculate reserves. China’s peak ionic rare earth output will be 46,797.06 tonnes in 2024, and then, it will decline at a 4% annual rate thereafter. This demonstrates how a graded reserve and orderly promotion can improve the workflow and efficiency of the rare earth mineral resources reserve.

Although some ions, due to their unique chemical properties, can regulate the enzyme-like activity of nanomaterials, it is still a huge challenge to explore the mechanism of regulation. Herein, we found that Cr

The Xiong’ershan district in central China hosts broadly coeval porphyry Au (Qiyugou deposit), porphyry Mo (Leimengou deposit), and barren (Huashan pluton) systems. The key controls on the ore potential and different mineralization styles in these systems are not well understood, with first-order differences in fluid chemistry and melt sources being the main alternatives. The fluid inclusion characteristics of all three porphyry systems have been studied using an integrated approach that combines field geology, petrography, microthermometry, and laser ablation–inductively coupled plasma–mass spectrometry analysis of single fluid inclusions. The results permit a reconstruction of the magmatic-hydrothermal evolution of the ore-forming fluids, and to elucidate whether specialized hydrothermal fluids strongly enriched in ore metals (i.e., Mo, Au, Cu) were essential to form the economically significant deposits. The fluid compositions across the three hydrothermal stages from the Qiyugou Au deposit remain approximately the same over time, suggesting that progressive magma fractionation, fluid-rock reaction along fluid path, and mineral precipitation had a limited effect on fluid composition. The syn-ore stage fluids of the Leimengou Mo deposit are characterized by higher Cs/Na, Sr/Na, and B/Na, but lower K/Na and Cl/Na ratios, and also have salinities and homogenization temperatures distinct from the earlier fluids. This demonstrates that Mo mineralization was caused by a second pulse of fluid input from a highly fractionated felsic magma subsequent to the pre-ore stage. At the Huashan barren pluton, fluids from phase II have higher Cs/Na, B/Na, Li/Na, and Rb/Na ratios with lower homogenization temperatures than fluids occurring in porphyritic rocks of phase III, reflecting a higher degree of magma fractionation of this plutonic complex. The Huashan pluton does not host economic mineralization which is likely caused by the low ore metal tenor, inefficient fluid extraction from the melt, or the flat-roof geometry preventing accumulation of a large volume of fluid in the apical part. The Au tenor of the Qiyugou deposit was most likely contributed by mantle-derived material of higher Mg/Na, Fe/Na, Pb/Na, and Zn/Na ratios. Taken together, the metal charged magmatic-hydrothermal fluids, steeply dipping geometry, and small volume of the porphyry stocks all suggest that a much larger magma chamber feeding the porphyry systems should be present at deeper levels with good potential for Mo mineralization below the current level of exposure at Qiyugou deposit.

Mitochondria are the power plants of the cell and play key roles in activating the apoptotic pathway in cancer cells, which are readily susceptible to cytotoxic reactive oxygen species and temperature elevations. Herein, we develop a “nanomissile” that targets mitochondria to enhance tumor treatment effects by facilitating mitochondrial dysfunction and releasing cytochrome C to activate the apoptotic pathway of cancer cells under 650-nm laser irradiation. Porphyrin-grafted polydopamine nanomaterial (PTPF-MitP) is designed as a nanomissile, with integrated O2-evolving photodynamic therapy and moderate photothermal therapy, which can selectively deliver to the mitochondria through a targeting unit, MitP. The cytotoxicity of PTPF-MitP to human lung tumor cells is twice as high as that of PTPF that does not have mitochondrial targeting units. In addition, it represents a realtime visualization and highly efficient treatment for tumor sites in vivo. This development represents a viable strategy for cancer therapy.

The Huangshui’an deposit located in East Qinling (China) is an unusual case of a Si-rich carbonatite hosting economic Mo and minor Pb and REE mineralization. The role of mantle-sourced carbonatite melts and fluids in the formation of the Mo mineralization remains poorly understood. Our integrated study based on field geology, petrography, microthermometry, and LA-ICP-MS analysis of single fluid inclusions, and noble gas isotopes of pyrite permits to reconstruct the source characteristics, the magmatic-hydrothermal evolution of the carbonatitic fluids, and their controls on Mo mineralization. Fluid inclusions hosted in calcite in the carbonatite dikes have the highest concentrations of Mo (9.9–62 ppm), Ce (820–9700 ppm), Pb (1800–19500 ppm), and Zn (570–5800 ppm) and represent the least modified hydrothermal fluid derived from the carbonatite melt. Fluid inclusions hosted in calcite (Cal) and quartz (Qz2 and Qz3) of the stage I carbonatite dikes have different metal concentrations, suggesting that they formed from two distinct end member fluids. The FIA in calcite represent fluid A evolved from carbonatite melt with relatively high-ore metal concentrations, and those in quartz characterize fluid B having a crustal signature due to metasomatic reactions with the wall rocks. The FIA in quartz (Qz1) within the altered wall rock have overlapping elemental concentrations with those of massive quartz (Qz2) and vuggy quartz (Qz3) in carbonatite. This suggests that the volumetrically significant quartz in the Huangshui’an carbonatite has been formed by the introduction of Si by fluid B. The positive correlations between Rb, B, Al, Cl, and Sr in stage II fluid inclusions in late fluorite + quartz + calcite veins indicate that this late mineralization formed from the mixing of primary hydrothermal fluid B with meteoric water. The He–Ar isotope data, in combination with available C–O–Sr–Nd–Pb isotope data, constrain the carbonatite source as an enriched mantle source modified by contributions from crustal material which was probably the fertile lower crust in the region. This distinct source facilitated the enrichment in Mo, REE, and Pb in the primary carbonatite magma. The carbonatite magmatism and Mo mineralization at 209.5–207 Ma occurred in the regional-scale extensional setting at the postcollision stage of the Qinling Orogenic Belt.

The tin (Sn)-tungsten (W) polymetallic ore concentrated district in SE Yunnan is distributed at the junction region of the Yangtze Block, the Cathaysian Block and the Indosinian Block, where there are several giant deposits of tin, tungsten, copper, silver, lead, zinc and indium closely associated with a large scale Late Cretaceous magmatism. Bi-dimensional empirical mode decomposition (BEMD) is used to extract aeromagnetic anomalous components at the survey scale of 1: 200 000 from the original aeromagnetic data of SE Yunnan. Four intrinsic mode functions (IMFs) and a residues component are obtained, which may reflect the geological structures and geological bodies at different spatial scales from high frequency to low frequency. The results are shown as follows: (1) Two different types of Precambrian basement in the study area were recognized: one is the Yangtze Block basement characterized by a strong positive magnetic anomaly, the other is the Cathaysian Block basement with a weak negative magnetic anomaly. The former consists of high grade metamorphic rocks including metamorphosed basic igneous rocks, while the latter consists of low grade metamorphosed sedimentary rocks. (2) The aeromagnetic anomalies associated with Sn-W polymetallic mineralization and related to granites in the study area illustrate a pattern of a skarnized alteration-mineralization zone with a positive ring magnetic anomaly enclosing a granitic intrusion with negative magnetic anomaly; (3) The ring positive magnetic anomaly zones enclosing the negative magnetic anomaly are defined as the Sn-W polymetallic ore-searching targets in the study area.

The Qiyugou Au deposit, located in the Xiong'ershan ore cluster of central China, consists of breccia pipe hosted Au ore bodies (>60 t Au) and newly discovered porphyry ore body (8 t Au). The porphyry Au mineralization occurs in the silicified core of the apical part of porphyritic granite stock which shows close spatial relationship with the auriferous breccia pipes. Here we present an integrated study involving detailed field investigation, textural studies, in situ pyrite trace element and sulfur isotope analysis, and U-Pb and Re-Os geochronology to elucidate the genetic relationship and hydrothermal evolution of the porphyry and breccia pipe mineralization. The SIMS sulfur isotopic analyses for the five pyrite generations show consistent δ34S values between −3.6‰ and 0.6‰, indicating that the two styles of Au mineralization had a mixed source including crustal and mantle-derived components. Zircon LA-ICP-MS U-Pb geochronology of two porphyritic granites yield weighted mean ages of 133.0 ± 0.6 Ma and 130.3 ± 0.9 Ma, and six molybdenite samples display an isochron age of 131.3 ± 1.1 Ma, representing the timing of granitic magmatism and Au mineralization in the 189 porphyry ore body. Available geochronological data allow us to constrain the timing of granitic magmatism and gold mineralization to be 135.6–134.1 Ma in the breccia pipes and 133.0–128.6 Ma in the porphyry ore. Among the five pyrite generations, Py1b and Py2b from the J4 breccia pipe are characterized by higher Co, Ni, and comparable contents of other elements (e.g. Au, Ag, Te, Pb, Zn, Cu and Bi) than those in Py1p, Py2p and Py3p from the porphyry ore. The widely consistent metal concentrations and linear relationship of metals in pyrite between the breccia pipe and porphyry ore are most probably the result of fluid exsolution from the same magmatic-hydrothermal system, whereas the enriched Co and Ni values from the J4 breccia pipe can reflect the composition of pyrite precipitating fluid at the early stage of the prolonged magmatic-hydrothermal system. The Qiyugou porphyry and breccia pipe mineralization show close spatial-temporal association and consistent source materials, and thus we propose that they resulted from multiple pulses of fluid exsolution from a large, deep-seated magma chamber.

China is promoting the production and use of electric vehicles (EVs) to achieve carbon neutrality. However, the shift will drive higher demand and tighter supply of nickel in China. We develop a stock-driven bottom-up dynamic substance flow analysis (SFA) model to simulate the demand trends of various EVs under 3 scenarios, the flow of nickel under 9 scenarios and the amount of recoverable nickel under 27 scenarios in China's EV industry from 2010 to 2050. The results indicate that China's current production capacity and primary reserves of nickel cannot meet the growing nickel demand, especially under the High EVs-LNCT scenarios, and closed-loop nickel recovery from EV batteries can effectively alleviate the demand-supply contradiction. In different scenarios, the annual recycling nickel could cover between 67.7 % and 96.6 % of the demand for EV batteries in 2050, and between 37.9 % and 58.1 % in terms of the cumulative quantity by 2050. When the low nickel battery technology is adopted and the recovery efficiency is rapidly improved, the recovered nickel would meet the demand for EV batteries to the highest degree. Therefore, sufficient attention should be paid to low-nickel battery technology and efficient recycling of spent EV batteries, which is of great significance to ensure the development of EV industry and the availability of nickel in China.

Gold clusters loaded on various supports have been widely used in the fields of energy and biology. However, the poor photostability of Au clusters on support interfaces under prolonged illumination usually results in loss of catalytic performance. Covalent organic frameworks (COFs) with periodic and ultrasmall pore structures are ideal supports for dispersing and stabilizing Au clusters, although it is difficult to encapsulate Au clusters in the ultrasmall pores. In this study, a two-dimensional (2D) COF modified with thiol chains in its pores was prepared. With -SH groups as nucleation sites, Au nanoclusters (NCs) could grow in situ within the COF. The ultrasmall pores of the COF and the strong S-Au binding energy combine to improve the dispersibility of Au NCs under prolonged light illumination. Interestingly, Au-S-COF bridging as observed in this artificial Z-scheme photocatalytic system is deemed to be an ideal means to increase charge-separation efficiency.

On account of its relatively low equilibrium potential, the electrocatalytic urea oxidation reaction (UOR) has promising application prospects for replacing the oxygen evolution reaction (OER) in boosting the cathode hydrogen production. To overcome the limitation of catalysts with only one active site, Ni–Sn dual sites, respectively pointing at the amino and carbonyl groups of the urea molecule, were designed based on the orbital symmetry matching principle to electrocatalytically oxidize urea at the anode for highly efficient hydrogen evolution at the cathode. The synthesized Ni–Sn sulfide catalyst, having a high active surface area (145 m2 g−1), displayed outstanding performance in the UOR with a low potential of 1.36 V (vs. RHE) at 10 mA cm−2 and achieved a high hydrogen production rate (100 L min−1 gcat−1) at the potential of 1.69 V (vs. RHE). The density functional theory studies combined with Raman experiments unveiled that the enhanced performance is due to the weakening of the urea C–N bond, resulting from the precisely designed Ni–Sn dual active sites, and the self-driven electron transfer between Ni and Sn. The synergistic strategy of point-to-point dual active sites developed here not only achieved a highly efficient UOR to boost hydrogen production, but also provides a new concept when designing catalysts for other catalytic reactions.

The Southern Great Xing'an Range (SGXR) which forms part of the eastern segment of the Central Asian Orogenic Belt (CAOB) is known as one of the most important Cu-Mo-Pb-Zn-Ag-Au metallogenic belts in China, hosting a number of porphyry Mo (Cu), skarn Fe (Sn), epithermal Au-Ag, and hydrothermal vein-type Ag-Pb-Zn ore deposits. Here we investigate the Bianjiadayuan hydrothermal vein-type Ag-Pb-Zn ore deposit in the southern part of the SGXR. Porphyry Sn ± Cu ± Mo mineralization is also developed to the west of the Ag-Pb-Zn veins in the ore field. We identify a five-stage mineralization process based on field and petrologic studies including (i) the early porphyry mineralization stage, (ii) main porphyry mineralization stage, (iii) transition mineralization stage, (iv) vein-type mineralization stage and (v) late mineralization stage. Pyrite is the predominant sulfide mineral in all stages except in the late mineralization stage, and we identify corresponding four types of pyrites: Py1 is medium-grained subhedral to euhedral occurring in the early barren quartz vein; Py2 is medium- to fine-grained euhedral pyrite mainly coexisting with molybdenite, chalcopyrite, minor sphalerite and galena; Py3 is fine-grained, subhedral to irregular pyrite and displays cataclastic textures with micro-fractures; Py4 occurs as euhedral microcrystals and forms irregularly shaped aggregate with sphalerite and galena. LA-ICP-MS trace element analyses of pyrite show that Cu, Pb, Zn, Ag, Sn, Cd and Sb are partitioned into pyrite as structurally bound metals or mineral micro/nano-inclusions, whereas Co, Ni, As and Se enter the lattice via isomorphism in all types of pyrite. The Cu, Zn, Ag, Cd concentrations gradually increase from Py1 to Py4, which we correlate with cooling and mixing of ore-forming fluid with meteoric water. Py2 contains the highest contents of Co, Ni, Se, Te and Bi, suggesting high temperature conditions for the porphyry mineralization stage. Ratios of Co/Ni (0.03–10.79, average 2.13) and sulphur isotope composition of sulfide indicate typical hydrothermal origin for pyrites. The δ34SCDT values of Py1 (0.42‰–1.61‰, average 1.16‰), Py2 (–1.23‰ to 0.82‰, average 0.35‰), Py3 (–0.36‰ to 2.47‰, average 0.97‰), Py4 (2.51‰–3.72‰, average 3.06‰), and other sulfides are consistent with those of typical porphyry deposit (–5‰ to 5‰), indicating that the Pb-Zn polymetallic mineralization in the Bianjiadayuan deposit is genetically linked to the Yanshanian (Jurassic–Cretaceous) magmatic-hydrothermal events. Variations of δ34S values are ascribed to the changes in physical and chemical conditions during the evolution and migration of the ore-forming fluid. We propose that the high Sn content of pyrite in the Bianjiadayuan hydrothermal vein-type Pb–Zn polymetallic deposit can be used as a possible pathfinder to prospect for Sn mineralization in the surrounding area or deeper level of the ore field in this region. Keywords: Trace elements, In-situ sulfur isotope, Pyrite, Bianjiadayuan deposit, Southern Great Xing'an range

Catalyst deactivation derived from slow conversion of Fe(III)/Fe(II) is the critical problem restricting catalytic efficiency of advanced oxidation. Herein, a novel multichannel healing strategy is proposed for fast healing structural damage by designing rationally smart platform (TiO2-CDs-FeOOH hollow sandwich hybrid). This ingenious system shows remarkable catalytic activity (0.77 min−1) and stability towards the removal of organic contaminants. Systematic studies confirm that the excellent catalytic activity is attributed to multiple electron transfer (MET) behavior at interface between photocatalytic substrate and FeOOH, leading to highly efficient interfacial charge separation and then fast recovery of Fe(II) on FeOOH surface during H2O2 activation process. Notably, multichannel healing procedure and MET kinetic information are unveiled by UV–vis/scanning electrochemical microscopy (SECM) through an in situ probe scanning technique. A higher ET rate constant keff (0.92 × 10-2 cm s-1) was revealed over TiO2-CDs-FeOOH, two times that of TiO2-FeOOH, further confirming that multi-channel electron transfer could achieve fast Fe(III)/Fe(II) conversion. This work offers a new insight to design highly efficient catalysts for the practical applications of sustainable environmental remediation and energy conversion.

A novel strategy toward monitoring of hydrogen peroxide (H2O2) through carbonaceous nanoplatform architectures (herein named as Cu(II)-LPQDs) is presented. Cu(II)-LPQDs were constructed by coupling Cu(II) complex with l -phenylalaninamide (LPN) functionalized N-doped carbon quantum dots (LPQDs). We have designed an efficient metal-ion-controlled mechanism to control peroxidase mimetic catalytic reactions. As the range of electron delocalization enhanced, the catalytic activity and stability of the mimetic peroxidase based on the Cu-N coordination unit increase significantly. By capturing the appearance of colorimetric and fluorescence changes, the detection of H2O2 in biological samples by qualitative and quantitative analysis is successfully realized. In our work, the detection limits of H2O2 by colorimetric and fluorescent methods are 80 nM and 2.5 μM, respectively. Its ultrasensitive-bidirectional properties are well described in-situ measurement in real samples and biological cells. The arresting feature of this method is green, simple, speedy, selective, sensitive and stable. Our findings provide clues to the intelligent nanoplatforms for the preparation of metalloenzymes without the use of noble metal elements for sensing applications and exhibit the highest peroxidase mimetic activity compared to other transition metals.

The development of industries in China’s resource-rich regions is mainly affected by resource reserves, environmental protection, and industrial structural adjustment. The development of resource-oriented industries that can’t support a high-quality regional economy is large but not well developed. This article considers China’s resource product imports and exports, carbon emissions, and industrial structure ratio factors in recent years. It is believed that China’s resource-rich regions have macro-level development bottlenecks, and the general development of a resource-based industries path is proposed based on the perspective of “resources, assets, and capital”. Taking Guangxi Zhuang Autonomous Region as an empirical case, this article analyzes the pattern of regional industrial development by using the input-output method, calculates the degree of inter-industrial correlation, and constructs a regional industrial development system. The results show the following: 1. China’s overall industrial development pattern has undergone major changes, 2. emerging industries and service-oriented industries have risen in development status, and although resource-based industries have a weaker development momentum, they still have an important position, 3. the hierarchical industry development management model is helpful for forming a regional circular economy innovation development pattern. The results also indicate that the integrated management of “resources, assets, and capital” has a positive effect on the development of resource-based industries in resource-rich regions, which affects the overall industrial development pattern of the region and promotes economic development.

The development of China’s resource industry is facing great pressures from industrial structure adjustment and environmental restraints, and the sustainable risk of the provincial resource industry is different. Considering the development of the resource industry and environmental pressure, this article selects the panel data of 31 provinces from 2015 to 2019 to construct an index evaluation system with six dimensions: influence, induction, supply and demand safety, regional pollution emission, environment quality, and pollution control. The results showed that Shanxi, Anhui, Jiangsu, and Shanghai had the highest sustainable risk in the resource industry, while Heilongjiang, Jilin, Tianjin, Fujian, Jiangxi, Hunan, Guizhou, Sichuan, and Qinghai had the lowest sustainable risk. The resource industry model of all the provinces is divided into sustainable, industrial, ecological, and unsustainable. Finally, this article puts forward reasonable suggestions for the four scenarios and argues that the balanced development of the resource industry sector and environmental protection is conducive to reducing the sustainable risks of the resource industry.

The Early Cretaceous (ca. 128 Ma) Shapoling vein-type molybdenum (Mo) mineralization, associated with the Huashan intrusion is a newly discovered deposit in the Xiong'ershan district, East Qinling, China where pyrite is a ubiquitous mineral phase. Here we present results from an integrated study on the texture, in situ trace element chemistry from laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and sulfur isotopic composition using secondary-ion mass spectrometry (SIMS), with a view to understand the geochemical variation, genesis of Mo mineralization and ore-forming process. The distinct textural patterns as revealed by petrographic observations suggest three types of pyrites: Py1 is composed of coarse-grained euhedral pyrite in the wall rock and early barren quartz vein at Stage I, Py2 is represented by subhedral-anhedral grains coexisting with molybdenite in quartz veins at Stage II, and Py3 forms irregular interstitial grains in the quartz + K-feldspar + molybdenite dominated veins at Stage III. The Mo enrichment mainly occurred in Py3 (with Co/Ni ratios >1 and δ34S values mainly

The Xiaoshuijing Syenogranite is the host of Mo mineralisation recently discovered in the Tengchong Terrane of southwestern China. Here, we present new zircon U-Pb ages and molybdenite Re-Os ages, whole-rock geochemical data, and zircon Hf isotopic data for the Xiaoshuijing Syenogranite hosting disseminated Mo mineralisation. The syenogranite’s mineralogical and geochemical characteristics indicate it is a high-K, alkaline, and peraluminous granite. LA-ICP-MS analysis of zircon yields an age of 65 ± 1 Ma (n = 14, MSWD = 2.1), and yields negative zircon eHf(t) values ranging from −18.23 to −12.92, interpreted to have a crustal source. The Re-Os Mo age of 64 ± 2 Ma (n = 4, MSWD = 2.2) for the mineralisation is the same as the syenogranite’s age, within error. The geochemistry also indicates that the syenogranite is related to a thickened crust resulting from the eastward subduction of the Neo-Tethyan oceanic lithosphere shortly before the collision of the Indian and Eurasian continental crusts.

Hexavalent chromium ion (Cr6+) is one of the most toxic substances for plants, for animals, and is a confirmed human respiratory carcinogen. However, so far, there are few independent and efficient colorimetric methods for detection of Cr6+. Here, we introduce a convenient, label-free, catalysis-based, and efficient strategy for quantification of Cr6+ by using a colorimetric sensing probe 3,3′,5,5′-tetramethylbenzidine (TMB). In the presence of a trace amount of gold amalgam nanocomposites (Au@Hg) and Cr6+, TMB can be oxidized to oxTMB and the color changed to an intense blue that was observed by naked-eye and absorption spectroscopic method. In addition, the colorimetric method shows the high selectivity against 34 other interfering substances, and it can be performed at room temperature, in water, and requires only ∼5 min. Thus, the catalysis-based colorimetric assay for accurate and ultrahigh selective identification of Cr6+ will find widespread use in the world.

Late Mesozoic granites are extensively distributed in the Luanchuan district of eastern Qinling and can be divided into two types: Late Jurassic to Early Cretaceous granites (ore-related plutons) and Late Cretaceous granites (Laojunshan batholith). This study presents new geochemical and zircon U-Pb-Hf isotopic data from the Shibaogou and Yuku plutons to provide robust constraints on the petrogenesis and tectonic significance of the late Mesozoic granites in the Luanchuan district. Zircon U-Pb dating results yielded weighted mean 206Pb/238U ages of 149.1 ± 0.8 Ma and 150.5 ± 0.8 Ma, which were interpreted as the crystallization ages of the Shibaogou and Yuku plutons, respectively. We propose that the late Mesozoic granites contain high concentrations of SiO2 and alkali elements (Na2O + K2O) and feature metaluminous to weakly peraluminous characteristics. Enrichment in light rare earth elements and large ion lithophile elements and depletion in high field strength elements are observed. Mineralogical and geochemical evidence reveal that the late Mesozoic granites are highly fractionated I-type granites with fractional crystallization of feldspar, plagioclase and accessory minerals (e.g., apatite and titanite or magnetite). Based on the Hf composition, we suggest that the parental magmas of the ore-related plutons were derived from remelting of the Taihua and Xiong’er groups with minor contributions of mantle-derived materials and that the Laojunshan batholith was generated by the hybridization of ancient crust- (Kuanping group) and mantle-derived components. Collectively, the above arguments indicates a tectonic transition from compression to post-collisional extension during the late Mesozoic, that was likely triggered by the continental collision of the North China Block and the Yangtze Block, which generated numerous contemporaneous granites and Mo-W-Pb-Zn-Ag-Au poly-metallic deposits.

The Early Cretaceous granitoids that are widespread in the Tengchong terrane of Southwest China play a critical role in understanding the tectonic framework associated with the Tethyan oceans. In this study, we present a detailed description of zircon U–Pb ages, whole-rock geochemistry and Hf isotopes for the Laoxiangkeng pluton in the eastern Tengchong terrane and elucidate their petrogenesis and geodynamic implications. Zircon U–Pb dating of the Laoxiangkeng pluton yields ages of 114 ± 1 Ma and 115 ± 1 Ma, which imply an Early Cretaceous magmatic event. The Laoxiangkeng pluton enriched in Si and Na, is calc-alkaline and metaluminous, and has the characteristics of highly fractionated I-type granites. Zircons from the pluton have calculated e Hf ( t ) values of −12.7 to −3.7 and two-stage model ages of 1327–1974 Ma, respectively, indicating a mixed source of partial melting of Paleo-Neoproterozoic crust-derived compositions with some inputs of mantle-derived magmas. By integrating all available data for the regional tectonic evolution of the eastern Tethys tectonic domain, we conclude that the Early Cretaceous magmatism in the Tengchong terrane was produced by the northeastward subduction of the Meso-Tethyan Bangong–Nujiang Ocean.

Recently identified Early Jurassic, Early Cretaceous, and Late Cretaceous granites of the Tengchong terrane, SW China, help to refine our understanding of the Mesozoic tectonic-magmatic evolutionar...

The Xing’an–Mongolia orogenic belt is located in the southeastern segment of the Central Asian Orogenic Belt. Its tectonic evolution, especially during the Late Palaeozoic to Early Mesozoic, remains controversial. Here, we report new zircon U–Pb dates, whole-rock geochemistry, and Hf isotopes of representative samples from four plutons in the Linxi area of Northeast China to provide new constraints on this issue. Zircon U–Pb dating indicates that the intrusions were emplaced in two stages: (1) Late Permian to Early Triassic (the Banshifangzi and Xinangou plutons (252 ± 3)–(246.3 ± 3.3) Ma); and (2) Late Triassic (the Baoshan and Hada plutons (220.8 ± 2.7)–(211.4 ± 2.6) Ma). Their positive εHf(t) values (6.6–14.1), coupled with their geochemical characteristics, suggest that the provenance of investigated granitoids were most likely to be dominated by juvenile crustal materials. Based on these new data and previous studies, we propose three stages of tectonic evolution during the Late Palaeozoic–Early Mesozoic in the XMOB: (1) Late Carboniferous–Early Permian (330–270 Ma): double-sided subduction of the Palaeo-Asian Ocean; (2) Middle Permian–Middle Triassic (270–237 Ma): the closure of the Palaeo-Asian Ocean and subsequent continent–continent collision between the North China Craton and the South Mongolia Terrane; and (3) Late Triassic (237–211 Ma): post-collisional extension.

New data from mineralogy, geochemistry, zircon U–Pb dating, and Hf isotopes have revealed Late Cretaceous to Eocene magmatic intrusions in the Tengchong terrane and constrained the origin, tectonic setting, and characteristics of tin-bearing and barren granitoids. We divide the studied granitoids into two groups: (a) the Late Cretaceous Zhinaxiang (70 Ma) and Early Paleocene Dazhupeng (65 Ma) S-type barren granites and (b) the Eocene Lailishan A2-type tin-bearing granite (50 Ma). All these granitoids display Si- and K-rich and calc-alkaline characteristics and have similar chondrite-normalized rare earth element patterns. However, geochemical differences do exist between the two groups of granites. The Zhinaxiang and Dazhupeng S-type granites are slightly peraluminous, enriched in large-ion lithophile elements (e.g., Rb and K), and depleted in high-field-strength elements (e.g., Nb, Ta, Zr, and Hf), whereas the Lailishan A2-type granite has higher TFe2O3, high-field-strength element content, and Ga/Al ratios. The geochemical and Hf isotopic data indicate that the granites in this study were generated by partial melting of Paleoproterozoic metasedimentary rocks. Due to the subduction of the Neo-Tethyan Ocean beneath the Eurasian plate, the Zhinaxiang and Dazhupeng S-type granites were formed in a thickened-crustal environment, whereas the Lailishan A2-type granite was emplaced in a post-collisional extensional setting attributed to slab break-off. By comparison between tin-bearing and barren granites, we propose that the Sn mineralization could be related to relatively high-temperature and low-pressure crystallization conditions.

The Late Mesozoic (i.e. 150–120 Ma) marks one of the most active periods of magmatism in the Southern Great Xing'an Range (SGXR), associated with large-scale mineralization. Here we investigate the large Shuitou fluorite deposit located within the SGXR mineralized belt. The ore bodies strike nearly NS and discontinuously extend for 10 km long. Zircon U–Pb dating of the associated intrusion (the Herimu Tai granite) in the southern part of the area yields an emplacement age of 136.9 ± 1.7 Ma whereas Sm–Nd isotopic data on the fluorite ore yield an isochron age of 132 ± 11 Ma. Fluid inclusions in the fluorite show low homogenization temperatures (140–220 °C), salinities (0.27 wt% NaCl eqv – 2.8 wt% NaCl eqv) and densities (0.86–0.891 g/cm3). The inclusions are mainly composed of H2O, along with minor C3H6 and other organic components. The associated calcite has δ13CV-PDB varying from −7.1‰ to −6.3‰ (average −6.73‰) and δ18OV-SMOW from −2.8‰ to −0.7‰. The field, petrologic and isotopic data from our study leads to the following salient findings. 1) The major minerals in the ore deposit include fluorite, quartz and calcite, which are of hydrothermal origin and have a uniform source and therefore the ore deposit is considered to be of hydrothermal vein-type. 2) The ore-forming fluids can be mainly attributed to NaCl–H2O system with moderate to low temperature, low salinity and low density. There is no evidence for post-magmatic hydrothermal fluid. The ore-forming fluid shows a meteoric water source, with water-rock reaction as the main mechanism for fluorite precipitation. 3) The deposit was formed in an extensional setting within the Central Asian Orogenic Belt and is closely associated with the late Jurassic to early Cretaceous polymetallic events. The nearly synchronous magmatic events in the study area suggest that these might have provided the heat source for fluorite mineralization.

The Lailishan deposit is an important tin deposit that is genetically associated with an Early Eocene biotite granite in the western Yunnan metallogenic belt in the Sanjiang region, SW China. This study reports new zircon U–Pb ages and Hf isotopic data, whole–rock elements, mica Ar–Ar age and C–H–O–S–Pb isotope for the Lailishan Sn deposit. The mineralization–related biotite granite crystallized during the Early Eocene (50.5 Ma), with its zircon eHf(t) values ranging from −11.5 to −7.6 and two–stage Hf model ages (T DM2 ) ranging from 1.60 to 1.85 Ga. The rocks are peraluminous with A/CNK values of 0.99–1.08. The granites display high Si, Al and K contents but low Mg, Fe and Ca contents. The rocks show flat chondrite-normalized REE patterns with strong Eu negative anomalies. These characteristics indicate that the magma originated from a continental crustal source. The hydrothermal muscovite exhibits an Ar–Ar plateau age of 50.4 ± 0.2 Ma. The δ 18 O and δD values of hydrothermal quartz from the deposit range from −7.32‰ to 4.01‰ and from −124.9‰ to −87.1‰, respectively. The δ 13 C PDB and δ 18 O SMOW values of calcite range from −11.3‰ to −3.7‰ and from +2.2‰ to +12.7‰, respectively. The sulfur isotopic compositions (δ 34 S V–CDT ) range from +3.3‰ to +8.6‰ for sulfide separates, and the lead isotopic ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb range from 18.668 to 18.746, from 15.710 to 15.743 and from 39.202 to 39.295, respectively. These isotopic compositions are similar to those of magma–derived fluids, indicating that the ore–forming fluids and materials mainly originated from magmatic rocks with some input from meteoric water. This evidence suggests that the tin mineralization is closely linked to the Lailishan I–type granites. In combination with previous data, it is proposed in this study that widespread early Eocene magmatism resulted from the slab breakoff of the subducting Neo-Tethyan slab at ca. 55 Ma.

In this paper, multi-source (geophysical, geochemical, geological and remote sensing) datasets were used to construct multi-scale (district-, deposit-, and orebody-scale) 3D geological models and extract 3D exploration criteria for subsurface Mo-polymetallic exploration targeting in the Luanchuan district in China. The results indicate that (i) a series of region-/district-scale NW-trending thrusts controlled main Mo-polymetallic forming, and they were formed by regional Indosinian Qinling orogenic events, the secondary NW-trending district-scale folds and NE-trending faults and the intrusive stock structure are produced based on thrust structure in Caledonian–Indosinian orogenic events; they are ore-bearing zones and ore-forming structures; (ii) the NW-trending district-scale and NE-trending deposit-scale normal faults were crossed and controlled by the Jurassic granite stocks in 3D space, they are associated with the magma-skarn Mo polymetallic mineralization (the 3D buffer distance of ore-forming granite stocks is 600 m) and the NW-trending hydrothermal Pb-Zn deposits which are surrounded by the Jurassic granite stocks and constrained by NW-trending or NE-trending faults (the 3D buffer distance of ore-forming fault is 700 m); and (iii) nine Mo polymetallic and four Pb-Zn targets were identified in the subsurface of the Luanchuan district.

In this study, graphene grafted Ag 3 PO 4 @AgBr (GO-Ag 3 PO 4 @AgBr) composite with enhanced photocatalytic performance was synthesized via in situ fabrication method. The synthesized composite was characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS) and X-ray photoelectron spectroscopy (XPS). The GO-Ag 3 PO 4 @AgBr composite was exhibited higher activity than Ag 3 PO 4 @AgBr and bare Ag 3 PO 4 . The material characterization and the detailed study of the various parameters which affect the photocatalytic reaction, revealed that the enhanced catalytic activity is related to the surface electric property of the synthesized catalyst. The investigation of the energy band structure further considered as a reason for the enhancement of the multi-electron reaction. Furthermore, the effect of illuminated light on the catalytic performance was also investigated. The results indicated that simulated sunlight significantly affects the catalytic activity compared with visible light. In addition, the photocatalytic experimental conditions were tested, and sonication of the dye/catalyst reaction system for 10 min was selected to be the optimum condition to establish absorption – desorption equilibrium. This work could supply a new way to use natural sunlight to facilitate the practical application of photocatalysts in environment issues.

Generally, 3,3′,5,5′-tetramethylbenzidine (TMB) cannot react with hydrogen peroxide (H2O2) in neutral pH or in water at room temperature and pressure. Herein, we found that hexavalent chromium (Cr6...

Coal will continue to be the main energy source in China for the immediate future, although the environmental pollution and ecological impacts of each stage in the full life cycle of coal mining, transportation, and combustion generate large quantities of external costs. The Late Permian coals in southwestern (SW) China usually contain high amounts of fluorine (F), arsenic (As), and ash, which together with high-F clays cause abnormally high levels of endemic fluorosis, As poisoning, and lung cancer in areas where coal is mined and burned. In this paper, we estimate the external costs of the life cycle of coal. The results show that the externalities of coal in SW China are estimated at USD 73.5 billion or 284.3 USD/t, which would have accounted for 6.5 % of the provincial GDP in this area in 2018. The external cost of human health accounts for 87.2% of the total external costs, of which endemic skeletal fluorosis diseases and related lung cancers have the most important impact. Our study provides a more precise estimate of externalities compared with its counterparts in other provinces in China. Therefore, several policy recommendations would be proposed to internalize the external cost.