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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 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.

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.

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 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.

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.

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.

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. ...

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.

The Fengjia barite–fluorite deposit in southeast Sichuan is a stratabound ore deposit which occurs mainly in Lower Ordovician carbonate rocks. Here we present results from fluid inclusion and oxygen and hydrogen isotope studies to determine the nature and origin of the hydrothermal fluids that generated the deposit. The temperature of the ore-forming fluid shows a range of 86 to 302 °C. Our detailed microthermometric data show that the temperature during mineralization of the fluorite and barite in the early ore-forming stage was higher than that during the formation of the calcite in the late ore-forming stage. The salinity varied substantially from 0.18% to 21.19% NaCl eqv., whereas the density was around 1.00 g/cm3. The fluid composition was mainly H2O (>91.33%), followed by CO2, CH4 and traces of C2H6, CO, Ar, and H2S. The dominant cation was Na+ and the dominant anion Cl-, followed by Ca2+, SO42-, K+, and Mg2+, indicating a mid–low-temperature, mid-low-salinity, low-density NaCl–H2O system. Our results demonstrate that the temperature decreased during the ore-forming process and the fluid system changed from a closed reducing environment to an open oxidizing environment. The hydrogen and oxygen isotope data demonstrate that the hydrothermal fluids in the study area had multiple sources, primarily formation water, as well as meteoric water and metamorphic water. Combined with the geological setting and mineralization features we infer that the stratabound barite–fluorite deposits originated from mid–low-temperature hydrothermal fluids and formed vein filling in the fault zone.

Three-dimensional (3D) district-scale geoscience information for the Luanchuan Mo district was integrated for understanding the development of its regional geology and ore-forming processes and for decision-making about potential targets for mineral exploration. The methodology and datasets used were: (1) construction of an initial geological model (25 km × 20 km × 2.5 km) using 1:10,000 scale geological map, nine geological cross-sections and gravity and magnetic data; (2) construction of three large-scale Mo deposits model (5 km × 4 km × 2.5 km) using 1:2000 scale geological and topographic maps, 288 boreholes (total core length of 158,700 m), and 32 1:2000 scale cross-sections; (3) 3D inversion of 1:25,000 scale gravity and magnetic data for identification metallogenic anomaly zones which are associated with Jurassic intrusions; (4) extraction of ore-controlling formation and sequence of the Luanchuan Group using the large-scale 3D models of Mo deposits and results of analysis of lithogeochemical samples from outcrops and borehole cores; (5) identification of ore-forming and ore-controlling faults using the large-scale 3D model of Mo deposits and mineralized Jurassic granite porphyry stocks; (6) boost weights-of-evidence and concentration–volume (C–V) fractal analyses to integrate metallogenic information and to identify and classify potential Mo targets. Four classes of exploration targets were identified using C–V modeling and 3D known orebodies model: the first and second class targets are mainly located in three large magma-skarn type deposit camps, occupying ~ 1.4 km3 with total estimated reserve of ~ 2.3 Mt; the third class targets, which are mainly located in Huangbeiling and Yuku deposit camps comprising concealed magma-skarn type deposits, occupy ~ 2.8 km3 and represent a new target exploration zone in the Luanchuan district; the fourth class targets, which are located in the Huoshenmiao, Majuan, and Daping zones, occupy ~ 15 km3 and represent potential mineral resources with likely similar orebody features as the Yuku deposit.

The Luanchuan metallogenic belt, located within the eastern part of the Qinling Orogen, central China, hosts a number of world-class Mo deposits that are closely related to small late Mesozoic granitic plutons. Zircon U–Pb dating of distinct plutons in the Luanchuan metallogenic belt has yielded ages of 153 ± 1, 154 ± 2, 152 ± 2, and 148 ± 1 Ma. Molybdenite Re–Os isotopic compositions of Yuku ore district in the southern part of Luanchuan metallogenic belt has yielded an isochron age of 146 ± 1 Ma, which is consistent with the large-scale mineralization ages in the northern part of the Luanchuan metallogenic belt. A combination of previous studies and new geochronological and isotopic data show a concordant temporal and genetic link between granitic magmatism and Mo mineralization in the Luanchuan metallogenic belt, suggesting that this mineralization episode formed the most extensive Mo mineralization belt in the east Qinling Orogen. Zircon grains from Mo-related granitic plutons show similar trace element distributions. High-precision Multi Collector–Inductively Coupled Plasma–Mass Spectrometry (MC–ICP–MS) Pb isotope analysis of K-feldspar megacrysts from mineralization-related granites suggest that they were derived from the lower crust. Similarly, the Pb isotopic compositions of pyrite coprecipitated with molybdenite also suggest that the metals were derived form the lower crust, with probably minor mantle contribution. A continuum mineralization model that describes the sourcing of Mo from an evolving granitic magma over successive differentiation events, possibly in separate but connected magma chambers, could explain the remarkable Mo enrichment in the Luanchuan metallogenic belt. The volatile- and Mo-bearing granitic magmas ascended as diapirs from the deep crust, and were emplaced as dikes in the upper crust. Lithological differences between these Mo-bearing granites may relate to different stages in the evolution of individual magmas. Finally, ore-forming fluids were exsolved from the granitic melts in shallow-crustal magma chambers, resulting in the formation of the Mo deposits of the Luanchuan metallogenic belt. This model may account for the widespread late Mesozoic Mo deposits of eastern China.

The Luanchuan Mo–W–Pb–Zn–Ag polymetallic ore district is located in the East Qinling metallogenic belt on the southern margin of the North China Craton. Two ore fields (Nannihu and Yuku) are recognized in the district, and three types of deposits are identified from the two ore fields as follows: (1) the 6 proximal porphyry–skarn type Mo–W deposits occurring at the inner contact zone of the granite porphyries, (2) the 3 middle skarn–hydrothermal type Zn deposits, and (3) the 8 distal hydrothermal type Pb–Zn–Ag deposits at the periphery of the porphyry. We present C–H–O isotope compositions of hydrothermal quartz and calcite, S–Pb isotope compositions of sulfide minerals, and sphalerite Rb–Sr isochron ages from the 17 deposits. The geochemical and geochronological data from the two ore fields all show systematic temporal and spatial variation, and primarily lead to the following inferences. (1) The temperatures and salinities of the ore-forming fluids decreased during mineralization. The ore-forming fluids gradually evolved from magmatic water to mixed magmatic–meteoric water. (2) The metallogenic components were primarily derived from igneous rocks, with increasing proportions of the materials from the ore-bearing rocks. (3) The mineralization ages of these deposits are close (147–136 Ma), which correspond to the emplacement of the granite intrusions. (4) The three types of deposits and the ore-related late Mesozoic intrusives constitute a unified magmatic–hydrothermal–mineralization system. Finally, we also suggest exploration strategies for the Luanchuan ore district.

Herein, we present a catalysis-based, label-free, and efficient strategy for a rapid, high-throughput, highly selective and ultrasensitive naked-eye colorimetric assay of Au

The Shanggong lode deposit represents one of the largest Mesozoic orogenic gold deposits in the East Qinling metallogenic belt of central China. Here we investigate the texture, trace element and sulfur isotopic composition of pyrite from this deposit to gain insights in the ore genesis. Three types of pyrite are recognized by its texture: Py1 is represented by coarse-grained cubic and pentagonal dodecahedron belonging to the stage I quartz-pyrite vein; Py2 comprises fine-grained disseminated pentagonal dodecahedron belonging to stage II quartz-sulfides vein; Py2 can be further divided into core and rim: porous cores (Py2c) carrying abundant, visible mineral inclusions and significantly higher arsenic concentration, and clean rims (Py2r) with low arsenic. Systematic LA-ICPMS trace elements and SIMS sulfur isotopic analyses reveal two distinct stages of mineralization with diverse source materials. 1) The early stage is represented by Py1 which contains 0.65–70 ppm Au (average 11.6 ppm), with relatively low and variable concentrations of Cu, Ag, Te, Pb, Zn, and Bi. The δ34S values of Py1 range from −2.7‰ to 7.2‰, suggesting that the sulfur source for the early stage fluid was mainly derived from the Taihua and Xiong’er Groups and that the depleted δ34S values reflect changes of pH, fO2 and fluid-rock interaction. 2) The main stage is represented by Py2 which contains Au in the range of 0.14–189 ppm (average 39.7 ppm). The Py2 carries significantly higher contents of compatible elements (Ni, Co, V, and Cr) and ore metals (e.g. Au, Ag, Pb, Zn, As, Te) than those in Py1, with the ore metals occurring as invisible lattice bound or nanosized particles and visible micron-sized inclusions. The δ34S values of Py2 show marked depletion with a range of −16.3‰ to −11.7‰, attributing to the fractionation between barite and sulfide minerals. Together with previous studies and trace element characters in Py2, we identify a contribution of Au from mantle source into the ore-forming fluid system during the main stage. We propose that the two stages of gold mineralization in the Shanggong deposit, in response to the collisional assembly of Qinling Orogenic Belt, preserve evidence for diverse metal sources with the early stage derived from partial melting of the lower crust (Taihua and Xiong’er Groups) in the compressional stage, and the main stage characterized by mantle contribution in a post-collisional extensional setting. Our findings may have important implications for the exploration of regional Triassic gold and molybdenum deposits.

Transition metal chalcogenides are investigated for catalyst, intermediary agency, and particular optical properties because of their distinguished electron-vacancy-transfer (EVT) process toward different applications. In this work, one convenient approach for making pure-phased FeSe nanocrystals (NCs) and doped CuFeSe nanosheets (NSs) through a wet chemistry method in mixed solvents is illustrated. The surface modification of each product is realized by using a peptide molecule glutathione (GSH), in which the thiol group (-SH) is ascribed to be the in situ reducer and bonding agency between the crystalline surface and surfactant in whole constructing processes. Due to the functional groups in biological GSH, highly aggregated NCs are rebuilt in the form of an FeSe hollow structure through amino and carboxyl cross-linking functions through a spontaneous assembly procedure. Owing to the coupling procedure of Cu and Fe in the growth process, it generates enhanced EVT. Additionally, it shows the emission spectra of λEM-PL = 436 nm (FeSe) and 452 nm (CuFeSe) while λEX-PL = 356 nm, it also conveys two-photon phenomenon while λEX-PL = 720 nm. Moreover, it also shows strong off-resonant luminescence due to two-photon absorption, which should be valuable for biological applications.