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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.

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 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...

Efficient charge separation and sufficiently exposed active sites are important for light-driving Fenton catalysts. 0D/2D hybrids, especially quantum dots (QDs)/nanosheets (NSs), offer a better opportunity for improving photo-Fenton activity due to their high charge mobility and more catalytic sites, which is highly desirable but remains a great challenge. Herein, a 0D hematite quantum dots/2D ultrathin g-C3 N4 nanosheets hybrid (Fe2 O3 QDs/g-C3 N4 NS) is developed via a facile chemical reaction and subsequent low-temperature calcination. As expected, the specially designed 0D/2D structure shows remarkable catalytic performance toward the removal of p-nitrophenol. By virtue of large surface area, adequate active sites, and strong interfacial coupling, the 0D Fe2 O3 QDs/2D g-C3 N4 nanosheets establish efficient charge transport paths by local in-plane carbon species, expediting the separation and transfer of electron/hole pairs. Simultaneously, highly efficient charge mobility can lead to continuous and fast Fe(III)/Fe(II) conversion, promoting a cooperative effect between the photocatalysis and chemical activation of H2 O2 . The developed carbon-intercalated 0D/2D hybrid provides a new insight in developing heterogeneous catalysis for a large variety of photoelectronic applications, not limited in photo-Fenton catalysis.

Herein, we developed a general strategy for rapid, highly selective, and ultratrace naked-eye colorimetric detection of Hg2+ in aqueous solutions. Two dimensional rGO/PEI/Pd nanohybrids, where rGO, PEI, and Pd were referred to as reduced graphene oxide, polyethylenimine, and Pd nanoparticles, respectively, were synthesized and used as mimetic peroxidase for selective and ultrasensitive detection of Hg2+ in water and human serum samples. In the presence of mercury ions, the peroxidase mimetic activity of rGO/PEI/Pd nanohybrids was found to be stimulated and enhanced significantly, which promoted the effective oxidation and color change of 3,3′,5,5′-tetramethylbenzidine (TMB) in solution to dark blue that was detected by the naked-eye and the absorption spectroscopic method. The proposed sensing strategy coupled with spectroscopic detection method showed an ultralow detection limit of 0.39 nM for Hg2+ in ddH2O and ∼1 nM in wastewater as well as serum samples, respectively. On the basis of the colorimetric a...

In order to obtain high selectivity and high quenching efficiency fluorescent sensors for 2,4,6-trinitrophenol (TNP), a ligand [5-(diethylamino)-2-((quinolin-8-ylimino)methyl)phenol hydrochloride, H2LCl] was obtained by the condensation of 4-(diethylamino)salicylaldehyde and 8-aminoquinoline in the present of HCl; and two Zn(II) complexes, namely [Zn2(μ2-L)(μ2-CH3COO)2Cl] (1) and [Zn2(μ2-L)2(NO3)2] (2), were also prepared via the reaction of H2LCl with Zn(AcO)2·2H2O or Zn(NO3)2·6H2O. 1 (in chloroform) and 2 (in methanol) showed strong emission centered at 498 nm and 540 nm respectively, and both of them displayed superior selectivity and high quenching efficiency to TNP among other nitroaromatics and analogues (i.e., 2,4,6-trinitrotoluene, phenol, nitrobenzene, o-nitrophenol, p-nitrotoluene, m-nitrotoluene, and salicylic acid). 6 equ. of TNP made 92% fluorescence quenching of 1, and 8 equ. of TNP induced 85% quenching of 2. The detection limits for TNP were found to be 0.154 ppm of 1 and 1.01 ppm of 2. © 2016 Elsevier B.V.

J- and H-aggregates of zinc tetraphenylporphyrin (ZnTPP) on carbon nanotube films (CNTFs) were prepared using the mixed solvent method. This resulted in completely different structures, such as the four-leaf clover and flower, on the CNTF, which were observed by recording SEM images. Characteristic changes in the electronic spectra of the ZnTPP monomer appeared when it underwent J- and H-aggregation. The measured photocurrent significantly varied for the same molecule when it was aggregated in two different ways on ITO and ITO/CNTF. The electron recombination resistance of the two aggregates, which was investigated using electrochemical impedance spectroscopy, was also different. The photocatalytic efficiency of the J- and H-aggregates was examined by performing methylene blue dye decoloration studies. In addition, a scanning electrochemical microscope was used to investigate the photoinduced charge transfer kinetics of the J- and H-aggregates at the electrode/electrolyte interface as a fresh attempt. The heterogeneous charge transfer constants for the J- and H-aggregates in the presence of light at varied intensities were calculated. Thereby, striking differences in the photophysical, photocatalytic, and photoelectrochemical properties of the J- and H-aggregates were visualized throughout our studies.

Isotopes (Rb Sr, C, O, S, and Pb) were investigated from the Zhenzigou Pb Zn deposit in the Qingchengzi mineral field (QMF) of the North China Craton as an aid to determine the genesis of stratiform Pb Zn deposits in the Liao-Ji Rift. A step-dissolution Rb Sr age of 1798 ± 8 Ma with 206Pb/204Pb ratios of 17.7477–17.8527 were obtained from sphalerite. Sulfur isotopic ratios for pyrite (5–14.4‰), sphalerite (2.4–8.6‰), and galena (− 0.3–8.6‰) from Zhenzigou have a narrower range than those from the host Paleoproterozoic Dashiqiao Formation, and granite in the area. Calcite and limestone from ore and wallrocks at the deposit have similar C and O isotope compositions, with δ13CPDB ranging from − 6.0 to − 2.3‰ and δ18OSMOW from 9.8 to 13.7‰, which are similar to those of carbonatite and the mantle. Comprehensive analysis of the Pb isotopic composition of the sulfide from the Zhenzigou deposit and Pb Zn deposits in adjacent area show that the Pb originated from the upper crust and mixed with Pb from the mantle. Sulfur isotopes from Zhenzigou deposit indicate that the mineralization has a volcanic eruption source. The δ13CPDB and δ18OSMOW values indicate that the CO2 originated from a mixed mantle, marine carbonate and organic source. Combined with the study of regional metallogenic background, this paper proposes that deposition of stratiform Pb Zn mineralization in the QMF began ca. 2052 Ma during development of the Liaoji Rift. The mineralization extended to ca. 1798 Ma prior to deformation associated with the Lvliang Movement, which dismembered the stratiform Pb Zn mineralization. The veined mineralization in the region cross-cuts the stratiform deposits and represents remobilized and redeposited deposits associated with the emplacement of Triassic plutons such as the Xinling and Shuangdinggou granites.

Xiaolonghe is a poorly studied greisen-type tin deposit that is hosted by biotite granite in the western Yunnan tin belt. The mineralisation-related metaluminous and weak peraluminous granite is characterised by high Si, Al and K and low Mg, Fe and Ca, with an average A/CNK of 1.02. The granite is enriched in LILEs (K and Rb), LREEs and HFSEs (Zr, Hf, Th, U and Ce) and depleted in Ba, Nb, Sr, P, and Ti, with zircon eHf(t) = − 10.8 to − 7.5 (T DM2 = 1.61–1.82 Ga). These characteristics indicate that the magma was generated by the partial melting of a thickened ancient crust. LA-ICP-MS U–Pb dating of igneous zircon and hydrothermal cassiterite yield ages of 71.4 ± 0.4 Ma and 71.6 ± 4.8 Ma, respectively. The igneous biotite and hydrothermal muscovite samples show Ar–Ar plateau ages of 72.3 ± 0.4 Ma and 70.6 ± 0.2 Ma, respectively. The close temporal relationship between the igneous emplacement and hydrothermal activity suggests that the tin mineralisation was closely linked to the igneous emplacement. The δ 18 O and δD values for the deposit range from + 3.11‰ to − 4.5‰ and from − 127.3‰ to − 94.7‰, respectively. The hydrothermal calcite C and O isotopic data show a wide range of δ 13 C PDB values from − 5.7‰ to − 4.4‰, and the δ 18 O SMOW values range from + 1.4‰ to + 11.2‰. The δ 34 S V-CDT data range from + 4.8‰ to + 8.9‰ for pyrite, and the 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb ratios range from 18.708 to 18.760, from 15.728 to 15.754 and from 39.237 to 39.341, respectively. The stable isotopic (C–H–O–S–Pb) compositions are all similar to those of magmatic and mantle-derived fluids, which indicate that the ore-forming fluids and materials were mainly derived from magmatic sources that were accompanied by meteoric water. The tin mineralisation in the Xiaolonghe district was closely associated with the Late Cretaceous crustal-melting S-type granites that formed during the subduction of the Neo-Tethys oceanic lithosphere. Combined with the tin deposits in the Southeast Asian tin belt, Tengchong block and Central Lhasa, we interpreted that a giant intermittent tin mineralisation belt should be present along the Asian Neo-Tethys margin.

The barite–fluorite metallogenic belt in southeastern Sichuan is one of the most important barite–fluorite ore-concentrated areas in China. In order to find the ore-forming source and the mineralization age of the Fengjia and Langxi barite–fluorite deposit, we systematically evaluated the rare earth element (REE) contents and isotopic characteristics of S, Sr, and Sm–Nd. The results show that the δ34S values of barites and pyrites are high and similar to S isotopic values of gypsum in the Cambrian Qingxudong Formation (∈1q), suggesting that the sulphur source was from Cambrian evaporite strata. The initial 87Sr/86Sr ratios of fluorites and barites range from 0.708800 to 0.712999, and these values are similar to Cambrian carbonate rocks and Lower Ordovician limestone. Except for black shales of the Lower Cambrian Niutitang Formation, the Ba content of other strata was generally low. The REE characteristics of barite and fluorite have close relationships, in regard to the source of ore-forming materials, to the Lower Cambrian Niutitang Formation black shales. Hence, we have concluded that the Cambrian carbonate rocks and Lower Ordovician limestone provide the source of calcium for mineralization and that the source of barium comes from the Lower Cambrian Niutitang Formation black shales. The fluorine contents of the Upper Sinian Doushantuo Formation and the Lower Cambrian Mingxinshi Formation are much higher than other strata, and these formations could provide the source for fluorine. The Sm–Nd isochron age of fluorites is 104 ± 11 Ma, which demonstrates that the mineralization mainly occurred during the late Yanshanian. Copyright © 2016 John Wiley & Sons, Ltd.

The petrogenesis and genetic relationship of molybdenum mineralization in the Late Mesozoic granitoids from the Xiong’ershan area remains controversial. This study presents integrated whole-rock geochemistry, zircon U-Pb geochronology and Hf-O isotopes for Late Mesozoic ore-bearing granite porphyry stock (Leimengou granite porphyry) and ore-barren plutons (Haoping and Jinshanmiao plutons) in the Xiong’ershan area of the East Qinling Orogen Belt (EQOB). The ore-barren granitoids are high-K subalkaline, metaluminous, and show negative correlations between Al2O3, MgO, TiO2, MnO, CaO, FeOT and P2O5 with SiO2. However, the Leimengou granite porphyry lacks distinctive linear correlation between major oxides with SiO2 except Al2O3, K2O and Na2O. These granitoids are enriched in LREE over HREE with slightly negative europium anomalies. Most samples show enrichment of Rb, Ba, Th, U, K and Pb, and depletion of Nb, Ta, P and Ti, mostly overlapping the ranges of the Taihua Group. Zircon U-Pb ages from the Haoping pluton, Jinshanmiao pluton and Leimengou granite porphyry are 130.9 ± 0.4 Ma, 127.7 ± 0.7 Ma and 131.5 ± 0.9 Ma, respectively. The Hf-O isotopic features of zircon from the Leimengou granite porphyry (δ18Ozircon = 5.03‰ − 5.86‰, eHf(t) = −24.3 to −14.4) are markedly similar with the Haoping pluton (δ18Ozircon = 5.17‰ − 5.61‰ and eHf(t) = −26.6 to −21.4). Zircon grains from the Jinshanmiao pluton have unique δ18Ozircon ranging from 6.01‰ to 8.90‰ and eHf(t) from −15.6 to −12.2. The co-variations of whole-rock geochemistry and Hf-O isotopic features in the samples suggest that Haoping pluton and Leimengou granite porphyry originated from mixture of partial melts of the Taihua Group with mantle-derived material, whereas the Jinshanmiao pluton originated from mixture of Xiong’er Group and mantle-derived material, with minor input of Taihua Group. The zircon grains from the Leimengou granite porphyry have significant higher Ce4+/Ce3+ (mean 547) and δEu (mean 0.65) ratios than those in the ore-barren Haoping pluton (mean 207 and 0.54, Ce4+/Ce3+ and δEu, respectively) and the Jinshanmiao pluton (mean 235 and 0.62, respectively). The main controlling factors for porphyry-type Mo mineralization are likely the oxygen fugacity (fO2) of the magma and input of mantle-derived material in the Xiong'ershan area. The geochemical and isotopic data show that the emplacement of these intrusions in the EQOB occurred in the post-collision settings during 132–127 Ma.

The Yujiadian F-Pb-Zn-Ag deposit in the South Great Xing’an Range (SGXR) consists of vein-type fluorite and F-Pb-Zn-Ag mineralization associated with granitoid. The orebodies occur in NS-trending extensional faults. Wallrock alterations are characterized by a series of medium-low temperature hydrothermal alteration, including silification, kaolinization, chloritization, sericitization, pyritic and carbonate alteration. Four stages of primary paragenetic sequences are recognized: polymetallic sulfide stage (stage I), sulfide fluorite sub-stage (stage II-1), silver-fluorite sub-stage (stage II-2), pure fluorite stage (stage III) and late carbonate stage (stage IV). Silver mineralization primarily belongs to the stage II. The 139–135 Ma quartz syenite porphyry is metaluminous and peralkalic, and is classified as A-type granite that formed in a post-orogenic extensional setting. The δ34S (1.8‰) of hydrothermal fluid calculated from coeval minerals (barite and galena) is comparable with the majority of adjacent magmatic hydrothermal deposits in the SGXR, implying a magmatic source. Microthermometric measurements show that ore minerals were deposited at intermediate temperatures (109.7–320.1 °C) and had low salinities (0.18–5.62 wt% NaCl equive). Ore-forming fluid originated from post-magmatic hydrothermal fluid and mixed with heated meteoric water. Successive precipitation of base metals occurred with changing physicochemical conditions and boiling of ore fluid. The main precipitation mechanism for fluorite in the late stage is related to fluid-rock reaction. We propose that the A-type granite related to the fracture-controlled hydrothermal vein-type Yujiadian F-Pb-Zn-Ag deposit forms part of the magmatic response to Paleo-Pacific subduction and associated lithospheric thinning, extension and delamination processes. Furthermore, the deposit represents the terminal and distal member of the regional Mesozoic large-scale mineralization events.

In this work, we discover an effective domino-effect-based detection mechanism for the rapid, high-selectivity, and ultrasensitive naked-eye colorimetric ratio assay of chromium(III) ion (Cr3+) in aqueous solutions. This naked-eye colorimetric ratio assay to Cr3+ relies on changes in absorbance properties that are due to the stimuli response of Cr3+ for the morphological transformation of silver nanoflakes. In the presence of Cr3+, large silver nanoflakes can be stimulated to transform to small nanoparticles (NPs), which promoted a color change in solution from bright yellow to wine red that was detected by the naked eye and spectroscopic absorption methods. The proposed naked-eye sensing strategy was coupled with an ultraviolet (UV)-spectroscopic chemosensor for the detection of trace Cr3+. The detection method showed an ultralow detection limit of 1.4 nM (nanomole) for Cr3+ in ultrapure water and 11.5 nM in human serum sample, respectively. On the basis of colorimetry, the lowest concentration of ∼50 nM for Cr3+ in ultrapure water and human serum can be detected by the naked eye. This naked-eye-based colorimetric ratio assay for accurate and selective identification and high sensitivity of Cr3+ is expected to have large potential and wide applications such as pharmaceutical analysis, clinical diagnosis, and environmental monitoring.

pH plays an important role in understanding physiological/pathologic processes, and abnormal pH is a symbol of many common diseases such as cancer, stroke, and Alzheimer’s disease. In this work, an effective dual-emission fluorescent metal–organic framework nanocomposite probe (denoted as RB-PCN) has been constructed for sensitive and broad-range detection of pH. RB-PCN was prepared by encapsulating the DBI-PEG-NH2-functionalized Fe3O4 into Zr-MOFs and then further reacting it with rhodamine B isothiocyanates (RBITC). In RB-PCN, RBITC is capable of sensing changes in pH in acidic solutions. Zr-MOFs not only enrich the target analyte but also exhibit a fluorescence response to pH changes in alkaline solutions. Based on the above structural and compositional features, RB-PCN could detect a wide range of pH changes. Importantly, such a nanoprobe could “see” the intracellular pH changes by fluorescence confocal imaging as well as “measure” the wider range of pH in actual samples by fluorescence spectroscopy. ...

Inspired by the spatial elaborate architecture and the kinetics characteristic of the nature photosynthesis, a nanohybrid of Au@THPP/CNTs with columnar-like shape has been prepared by a combination of the gold-4-hydroxyphenyl porphyrin nanohybrid of core–shell structure (Au@THPP) and vertically aligned carbon nanotubes (CNTs) grown on a transparent conducting substrate. A simplified model to uncover the partial electron transfer (ET) of photosystem II (PSII) using the nanohybrid by the chemical approach has been set up. The UV–vis/scanning electrochemical microscopy (UV–vis/SECM) platform, a simple, effective, and novel electrochemistry method, was used to investigate the behavior of photoinduced electron transfer of the model. At 560 nm wavelength, the heterogeneous electron transfer rate constant (keff) of this model is the highest, which is consistent with the maximum absorption wavelength of a different chromophore achieved in photosynthesis. The model is not only of great value to study the complex p...

A simple amine embellished tube array was assembled at the liquid–liquid interface to study ion transfer behavior. Variation in the pH of the solution resulted in three different protonation states at the amino groups of the nanochannel, which in turn regulated ion transport, similar to the switching effect of ion channels in vivo.