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We studied the fluid inclusions of the Jiguanshan Mo deposit in China, which is a large porphyry deposit located in the southern Xilamulun Metallogenic Belt. The irregular Mo ore body with various types of hydrothermal veinlets is hosted by Late Jurassic granite porphyry. Intense hydrothermal alterations in the deposit from the core to margin are silicification–potassium feldspar alteration, pyrite–quartz–sericite–fluorite alteration, and propylitic alteration. Based on the mineral assemblages and crosscutting relationships of ore veins, the ore-forming process were divided into three stages and two substages: quartz–pyrite veins (stage I) associated with potassic alteration; quartz–molybdenite–chalcopyrite–pyrite veins (substage II-1) and quartz–molybdenite–fluorite veins (substage II-2) associated with phyllic alteration; and fluorite–quartz–carbonate veins (stage III) with carbonation. Five major fluid inclusions (FIs) types were distinguished in the quartz associated with oxide and sulfide minerals, i.e. polyphase brine (Pb-type), opaque-bearing brine (Ob-type), solid halite (S-type), two-phase aqueous (A-type), and vapor (V-type) inclusions. The FIs of stage I were composed of liquid-rich S-, A-, and V-type FIs with homogenization temperatures and salinities of 490 to 511 °C and 8.9 to 56.0 wt% NaCl equiv., respectively. The FIs of substage II-1 are composed of Pb-, Ob-, S-, A-, and V-type FIs with homogenization temperatures and salinities of 352 to 460 °C and 3.7 to 46.1 wt% NaCl equiv, respectively. The FIs of substage II-2 are Ob-, S-, A-, and V-type FIs with homogenization temperatures and salinities of 234 to 309 °C and 3.7 to 39.2 wt% NaCl equiv, respectively. The FIs of stage III are A-type FIs with homogenization temperatures and salinities of 136 to 172 °C and 1.1 to 8.9 wt% NaCl equiv, respectively. Fluid boiling, which resulted in the precipitation of sulfides, occurred in stages I and II. The initial ore-forming fluids of the Jiguanshan deposit had high temperature, high salinity, and belonged to an F-rich NaCl ± KCl–H2O system. The fluids gradually evolved to low temperature, low salinity, and belonged to a NaCl–H2O system. Studies of the hydrogen and oxygen isotope compositions of quartz (δ18OH2O = − 7.3 to 6.3‰, δDH2O = − 104.3 to − 83.3‰) show that the ore-forming fluids gradually evolved from magmatic water to meteoric water.

Black phosphorus (BP) has become a novel focus of the 2D material due to its natural direct band gap and high carrier mobility, but researchers seldom refer to the water-BP interfacial properties while the natural rippled surface of the BP raises great hope to develop the controllable fluid transmission devices. In this paper, the interfacial slip and friction between monolayered BP and water are first investigated using classical molecular dynamics simulations based on the BP sheet-water Couette model. The results show that the rippled structure of the BP surface leads to the anisotropic boundary slip and interfacial friction between water and BP sheets. The maximum boundary slip and the minimum interfacial friction are obtained for the water flow direction parallel to the ripple direction of BP monolayer. With increasing the intersection angle between water flow direction and BP ripple direction, the boundary slip decreases and the interfacial friction increases continuously. The mechanism of the anisotropic interfacial properties is clarified from the configuration of the water molecules adjacent to the BP surfaces. This finding will generate excitement in designing the BP-based fluid transmission device.

The Middle Triassic Laojiagou porphyry Mo deposit is located in the Xilamulun metallogenic belt, along the northern margin of the North China Craton (NCC). Molybdenum mineralization is associated with a monzogranite porphyry and occurs primarily in quartz veins and veinlets hosted in wall rocks affected by potassic, silicic, sericitic, and propylitic alteration. The ore-forming process is divided into three stages, characterized by veinlets comprising molybdenite + pyrite + quartz (stage I), pyrite + chalcopyrite + molybdenite + quartz (stage II), and pyrite + quartz (sulfide-poor) (stage III). We identify three fluid inclusion types in quartz grains: carbonic (C-type), liquid-rich two-phase (L-type), and rare vapor-rich two-phase (V-type) inclusions. Microthermometric results indicate that an initial high-temperature (> 350 °C) and low-salinity (

The Angeer Yinwula Pb–Zn deposit of Inner Mongolia, China, is located in the Erlianhot–Dongwuqi metallogenic belt, which is considered to be the eastern part of the Central Asian Orogenic Belt. We used the ore geology, fluid inclusion, isotopes, and zircon U–Pb geochronology to elucidate the genesis and tectonic setting of the deposit. The deposit belongs to the moderate-temperature hydrothermal-vein type, and most of the ore bodies occurred in the quartz diorite intrusions and silty slate country rocks of the Devonian Angeer Yinwula Group. Fluid inclusion petrography and microthermometry results show that the inclusions that developed in the different mineralization stages changed from the LV type (vapor-rich two-phase) + S type (daughter-mineral-bearing three-phase) + VL type (liquid-rich two-phase) to the VL type + LV type and eventually evolved into the VL type, and the ore-forming fluids changed from a moderate-temperature and moderate- to high-salinity, boiling fluid system to a low-temperature and low-salinity H2O–NaCl system. The isotope (C, H, O, S) characteristics suggest that the ore-forming fluids were derived from a magmatic source, and the lead was derived from a deep-seated mantle-derived magma and also included some crustal material. The LA–ICP–MS zircon U–Pb age of the quartz diorite is 152.0 ± 1.5 Ma, which is the best estimate for the age of mineralization of the deposit. Overall, we suggest that the deposit formed in a Late Jurassic Paleo-Pacific Plate subduction setting, although this hypothesis needs to be further tested by conducting computational simulations in the field of emerging computational geosciences.

Development of the efficient bifunctional oxygen electrode is indispensable but challenging for the rechargeable metal–air batteries. The oxygen reduction reaction and oxygen evolution reaction of theTMN4 embedded graphene, graphane and fluorographene are systematically investigated by the density functional theory calculations (TM = Fe, Co and Ni). Our results show that the ORR/OER activity and the stability of the TMN4 moieties are dramatically changed by the graphene functionalization. According to the free energy analysis, the H/F decoration on the carbon skeleton improves the activities of FeN4 and CoN4 moieties, in comparison with the graphene counterpart. In detail, the FeN4-based electrodes are potential ORR ones where the overpotentials are reduced from 0.98 V of G/FeN4 to 0.46 V of GH/FeN4 and 0.38 V of GF/FeN4. Meanwhile, the CoN4-based electrodes possess good OER efficiency featured with the overpotentials of −0.50 V and −0.53 V for GH/CoN4 and GF/CoN4 with respect to −0.72 V for G/CoN4, respectively. On the other side, the high thermodynamic barrier of NiN4-based electrodes limits its application, regardless of the supports. Furthermore, the binding strengths between TM and its N coordination are substantially increased due to the presence of H/F attachments, indicating the enhanced TM capture, which ascribes to the corresponding wrinkle sp3 structure. Additionally, the structural integrity without any degradation in the molecular dynamic stimulation further supports the thermodynamic stability at the room temperature. The robustness of GH/TMN4 and GF/TMN4 illustrates the feasibility of the experimental synthesis. Considering the possible dehydrogenation of the graphane at the elevated temperature, the fluorographene with atomically dispersed FeN4 and CoN4 moieties is recommended as promising oxygen electrode. To shed light on the physical origination, the electronic structure analysis correlates the activity enhancement with the change of the TM d-orbital, being evidenced by the linearity between the OH affinity and the d band center. Therein, the influences of the graphene functionalization on the electrocatalysis provide new insights into the design of the bifunctional oxygen electrode.

Herein, zircon U-Pb geochronology, Lu-Hf isotopes, and whole-rock major and trace element geochemistry are presented for two Palaeoproterozoic granitic rocks in Qingchengzi district, northeastern Jiao-Liao-Ji Belt (JLJB). These new geochronological and geochemical data provide reference clues for exploring the petrogenesis and tectonic setting of Paleoproterozoic magmatic rocks in the Qingchengzi district, which further constrain the tectonic nature of the JLJB. Our zircon U-Pb dating denotes that the Paleoproterozoic magmatic events in the Qingchengzi district were emplaced at ~2163 Ma and ~1854 Ma, represented by granite porphyry and biotite granite, respectively. Geochemically, these Palaeoproterozoic rocks are characterized by high Sr (760&ndash, 842 ppm), SiO2 (69.72&ndash, 70.89 wt.%), and Al2O3 (15.53&ndash, 16.78 wt.%) contents, low Y (2.1&ndash, 9.0 ppm) and Yb (0.25&ndash, 0.80 ppm) contents, which indicate an adakite affinity. Combined with Hf isotopic composition (&epsilon, Hf(t) = &minus, 1.5~+4.8, TDM2 = 3109~2560 Ma), we believe that the Paleoproterozoic adakitic magma originated from partial melting of the thickened lower crust material in the Meso-Neoarchean. Moreover, these rocks are enriched in light rare earth elements and large ion lithophilic elements (e.g., K, Rb, and Cs), and depleted in heavy rare earth elements and high field strength elements (e.g., Nb and Ta). These features are similar to magmatic rocks formed in an arc environment (either island arc or active continental margin) and are not consistent with an intraplate/intracontinental environment. According to this study and previous research results, we conclude that the arc&ndash, continent collision model is conducive to the Paleoproterozoic tectonic attribute of the JLJB, and the oceanic crust subduction between the Namgrim and Longgang blocks may have induced the widespread occurrence of magmatic events in the region.

The Qingchengzi Au–Ag orefield is a key Au province in the North China Craton. The fault-controlled orebodies are hosted in the Paleoproterozoic meta-sedimentary rocks of the Dashiqiao and Gaixian Formations. We present new bulk-ore REE, fluid inclusion (FI) microthermometric and mineral H–O–S–Pb isotopic data of these Au–Ag deposits, and discuss their ore fluid/material source and metallogenesis. Our FI microthermometric data indicate that the ore fluids are of medium temperatures (260–310 °C), low salinity (≤10 wt% NaCl eq.), and belonged to a H2O–CO2–NaCl system. Hydrogen (δD = –6.5 to 9.1‰) and oxygen (δ18O = –139.4 to –90.1‰) isotopes of the hydrothermal quartz indicate that the early-stage ore-forming fluids were mainly magmatic sourced. The δ34S values (–12.5 to 18.7‰) of the ore sulfides overlap with the Paleoproterozoic ore host (δ34S = –0.5 to 13.2‰) and the Late Triassic granites (δ34S = 5.6–7.6‰). Lead isotope compositions of the ore sulfides (206Pb/204Pb = 17.269–18.334; 207Pb/204Pb = 15.335–15.883; 208Pb/204Pb = 37.254–38.784) also support a metallogenic link with the granites and wall-rocks. Therefore, we suggest that the Qingchengzi Au–Ag deposits are best classified as magmatic-related medium-temperature hydrothermal lode type, albeit spatial correlations with magmatic intrusions are not ubiquitous. Closer to the hydrothermal centers, the higher-temperature, magmatic-dominated fluids were responsible to generate the Au(-Ag) mineralization, whereas the more distal, lower-temperature magmatic-meteoric-mixed fluids may have formed the Ag and Pb–Zn mineralization. The ore-forming fluids and materials were likely sourced mainly from the Triassic granitoids, although significant contributions of ore metals and sulfur from the Au-/Ag-rich Dashiqiao and Gaixian Formations should not be neglected. Considering the regional tectonic setting, the Late Triassic Qingchengzi Au–Ag polymetallic mineralization may have occurred during the post-collisional extension after the Yangtze-North China continent–continent collision.

The Qingchengzi Pb–Zn deposit is located in the northeastern Jiao–Liao–Ji Belt (JLJB), North China Craton (NCC). Field observation and age dating indicate that the deposit was formed from Paleoproterozoic sedimentary exhalative (SEDEX) stratiform mineralization overprinted by Late Triassic hydrothermal vein-type mineralization. Five types of fluid inclusions (FIs) are identified in the quartz grains, based on petrography and laser Raman spectroscopy: liquid-rich two-phase (type 1), vapor-rich two-phase (type 2), CO2-bearing (types 3a and 3b), and CO2-pure (type 4). Quartz from the SEDEX stratiform ores contains only type 1 FIs, and hydrogen-oxygen isotopic compositions indicate that the ore-forming fluids were magmatic water-derived. The ore-forming fluids were likely of medium-temperatures and low-salinity, and belonged to a NaCl–H2O hydrothermal system. Quartz from the vein-types contains all five types of FIs, and the ore-forming fluids may have belonged to a medium-temperature, low-salinity NaCl–H2O–CO2 hydrothermal system. Hydrogen-oxygen isotopes indicate that the vein-type ore-forming fluids were derived from magmatic-meteoric mixed source. Rare-earth element (REE) and sulfur-lead isotopic compositions indicate that ore-forming materials of the SEDEX stratiform mineralization were derived from the wall-rocks and magma, wheres those of the vein-type mineralization were derived from Late Triassic granitic magma, wall-rocks, and the Paleoproterozoic SEDEX ores. Based on field geological and geochronological data, we propose the following regional metallogenic model: (1) SEDEX mineralization occurred during the Paleoproterozoic post-collisional extension in the JLJB; (2) vein-type mineralization was generated by the north-dipping subduction of the Yangtze Craton beneath the NCC, which led to continent-continent collision and slab break-off in the Late Triassic.

With the rapid development of low-dimensional materials, the opportunity that promotes the development of micro/nano fluid devices, a new low-dimensional material black phosphorus (BP) has attracted wide attention due to its excellent properties, and has been applied to many areas. In this paper, the influences of driving force, water-BP anisotropy, channels’ width and the number of black phosphorus layers on the flow characteristics of water molecules in the nanochannels are studied by molecular dynamics based on the Poiseuille flow model. The results show that the boundary slip velocity increases with the driving force increasing. The anisotropy will also affect the flow characteristics of water molecules in the nanochannel under the pressure driving the Poiseuille flow. Specifically, the boundary slip velocity decreases with the chirality angle increasing, and the viscosity coefficient of water molecules is still not affected by the anisotropy. The natural rippled structure of the BP surface leads to the coarse potential surface, and further results in the anisotropic boundary slip and interfacial friction between water and BP sheets. With the driving acceleration kept constant, the influences of the width of nanochannels and the number of black phosphorus layers on the boundary slip velocity and viscosity coefficient of water molecules are investigated. The results indicate that the slip velocity of water molecules in the nanochannels decreases with the width of the nanochannels increasing. The velocity profile of water molecules in the bilayer model is slightly different from that in the monolayer model. With the number of BP layers increasing, the energy of BP-water solid-liquid interface increases while the anisotropic interfacial property remains unchanged. The results will provide a theoretical basis for the study of the characteristics of the fluid flowing in the black phosphorus nanochannels and the design of micro/nano fluid devices based on black phosphorus materials.

A new species of Paracleistostoma De Man, 1895, P. meilanense n. sp. is reported from mangroves forests in Haikou, Hainan Province, China. The new species inhabits mud burrows in the upper intertidal zone and is sympatric with P. tomentosa YangSun, 1993, and P. depressum De Man, 1895. The slender chelipeds as well as the characteristic morphology of the male first pleopod easily distinguishes the species from congeners.