The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although...The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although the Chating large porphyry Cu-Au deposit and a few middle-sized skarntype Cu polymetallic deposits have been discovered.In this study,we carried out high-resolution seismic reflection,magnetotelluric,gravity,and magnetic investigations,and constructed the 3 D geological structure of the uppermost crust in a depth range of 0-5 km using a comprehensive inversion of the new data constrained by previous deep-drilling data.We hence proposed some new insights to understand the mineralization processes of this district.A system of alternating ridges and valleys is suggested as the major structure pattern,composed of“two-layer structure”of the basins and“three-layer structure”of anticlines.Moreover,a conjugated fault system and its distribution features are revealed in our models,including the Jiangnan fault,Zhouwang fault,and Kunshan thrust nappe.The Jiangnan and Kunshan faults are suggested to have controlled the diagenesis and metallogenesis.Two deep concealed plutons located in Chating and Magushan are found,forming the Mesozoic diorite-felsic intrusions.These intrusions are believed to be the causes of hydrothermal deposits such as the Chating deposit and the Magushan deposit.展开更多
The Early Cretaceous aluminous A-type granites in the Lower Yangtze River belt(LYRB)can provide important insights into the Mesozoic magmatism in eastern China,but their origin remains highly controversial.In this stu...The Early Cretaceous aluminous A-type granites in the Lower Yangtze River belt(LYRB)can provide important insights into the Mesozoic magmatism in eastern China,but their origin remains highly controversial.In this study,radiogenic Ca-Nd isotopic analysis was performed for syenite porphyry and alkali-feldspar granite porphyry of the Yangshan pluton,a typical aluminous A-type granitic intrusion in the LYRB,to constrain its source and geodynamic setting.The results show thatε_(Ca)(126 Ma),ε_(Nd)(126 Ma)and K/Ca_(source) of the syenite porphyry range from-0.24 to+0.96,-7.2 to-6.0,and 0.31 to 1.26,respectively.The corresponding values for the alkali-feldspar granite porphyry range from 0.26 to 0.84,-8.0 to-6.1,and 0.79 to 1.08,respectively.Binary mixing modeling indicates that they were originated from the same sources with different proportion,namely,a mixing of 50%to 75%Neoproterozoic crust and 50%to 25%asthenospheric mantle.Together with previous works,we propose that the Early Cretaceous subduction of the ridge between the Pacific and Izanagi plates was responsible for the formation of the aluminous A-type granites in the LYRB.展开更多
0.INTRODUCTION.The Jiuwandashan Sn-polymetallic ore cluster,located in the western part of the Jiangnan Orogen and the Nanling Metallogenic Belt,is one of the most significant Precambrian tin ore concentration areas i...0.INTRODUCTION.The Jiuwandashan Sn-polymetallic ore cluster,located in the western part of the Jiangnan Orogen and the Nanling Metallogenic Belt,is one of the most significant Precambrian tin ore concentration areas in South China(Figure 1a;Mao et al.,1987).Recently,this region has garnered considerable research attention due to its intense mafic-felsic magmatic activity and large-scale Sn-polymetallic mineralization(Li et al.,2020;Chen J F et al.,2019;Huang and Wang,2019;Zhang et al.,2019;Chen L et al.,2018;Xiang et al.,2018;Su et al.,2014).A series of medium-to large-scale Sn-polymetallic deposits,including Jiumao,Liuxiu,Yidong,Honggangshan,and Shaping(Figure 1b),have been identified within this region,with proven tin reserves of approximately 200000 t.High-precision dating methods have yielded cassiterite U-Pb ages of ca.830 Ma,pointing to a Neoproterozoic Sn-polymetallic mineralization event in South China(Zhang et al.,2019;Xiang et al.,2018).展开更多
The paper presents an overview of the relationships between the interior structures of tectonic terranes and the distribution of tectonic-metallogenic zones in Southeast Asia. Episodic tectonic activities occurred in ...The paper presents an overview of the relationships between the interior structures of tectonic terranes and the distribution of tectonic-metallogenic zones in Southeast Asia. Episodic tectonic activities occurred in this archipelagic area, generating metallogenic belts in multi-terranes. Since the Late Paleozoic, opening and closure of the Paleotethys and Neotethys led to multiple suture zones between different blocks, mainly between the Indochina terrane, the Nambung terrane, the Sibumasu terrane and the West Myanmar terrane. During the Mesozoic to Cenozoic, the formation of accreted terranes and their related islands was caused by subduction and collision processes between the Pacific and Australian plates toward the Eurasian Continent, forming Sundaland and its affiliated islands, the Philippines and its subsidiary islands, the Papua New Guinea terrane and its related islands and the Sunda epicontinental arc system. Within the margin of terranes resulted in the structural transfer zones, their secondary tectonic units can be divided into island arc belts, back-arc basins, suture zones, marginal fold belts and orogenic belts. The metallogenic assemblages are mainly distributed within these structural zones of the terranes. According to the relationship between these tectonic units and the distribution of mineral resources, the tectonic-metallogenic belts can be divided into 24 metallogenic belts in Southeast Asia. They are characterized by a diversity and frequency of metallogenic material combination which is likely to reflect the complexity of the material distribution during mineralization processes, mostly by the structural transformation during the dissociation-convergence process between multiple terranes. Therefore, the formation of ore deposits was not only restricted by the evolution(opening and closure) of Paleo-and Neotethys, but may also be controlled by the interaction of the terranes with different tectonic attributes which provided multiple sources of metallogenic material.展开更多
Recently measured high gamma ray values in the Yanchang Formation of the Upper Triassic in the Ordos Basin have added an interesting and controversial twist to the study of the formation’s uranium enrichment and gene...Recently measured high gamma ray values in the Yanchang Formation of the Upper Triassic in the Ordos Basin have added an interesting and controversial twist to the study of the formation’s uranium enrichment and genesis.High uranium and thorium contents in the tuffaceous layer cause high gamma ray values in the Yanchang Formation.Petrographic studies,major elements,rare earth elements(REEs),and trace elements have been systematically analyzed to determine the composition,geochemical environment,and diagenetic processes of the layer.The observed color of the tuffaceous layer in the study area varies from yellow to yellowish brown.The tuff consists of matrix supported with sub-rounded to sub-angular lithic fragments.These lithic fragments probably derived from pre-existing rocks and incorporated into the tuffaceous layer during volcanic eruption.Quartz,plagioclase,and biotite were observed in well to poorly sorted form,in addition to framboidal pyrite and organic laminae.Measured ratios of SiO_2/Al_2O_3 ranged from 3.277 to 6.105 with an average of 3.738.The ratio of TiO_2/Al_2O_3 varied from 0.037 to 0.201 with an average of 0.061,indicating that the sediments of the tuffaceous layer originated from an intermediate magma.REE distribution patterns show sharp negative Eu anomalies,indicating a reducing environment,which is suitable for uranium deposition.A reducing environment was confirmed by black shale in the base of the Yanchang Formation.Such black shale has high organic matter content that can take kerogene from mudstone and provide a reducing environment for uranium enrichment in the tuffaceous layer.Moreover,negative Eu anomalies and the REE patterns indicate a subduction-related volcanic arc environment as the magma source of the tuffaceous layers.High values of Rb,Ba,and Sr might be the result of fluid phase activities;low values of Hf and Eu indicate the involvement of crustal material during diagenesis of the tuff.Discrimination diagrams(Th/Yb vs Ta/Yb,Th/Hf vs Ta/Hf)suggest an active continental margin as the tectonic setting of source volcanoes.Plots of Nb versus Y,Rb versus Y+Nb,TiO_2 versus Zr,and Th/Yb versus Nb/Yb of the tuffaceous content point to calc-alkaline continental arc-related magmatism.We concluded that uranium enrichment in the tuffaceous layer was supported by oxidation–reduction.展开更多
Piaoac granites exposed in the Cao Bang region, northern Vietnam, are S-type granite, which are associated with W-Sn-Mo-Be-F mineralization. Zircon U-Pb ages, major and trace elements, mineral chemical and Hf isotopic...Piaoac granites exposed in the Cao Bang region, northern Vietnam, are S-type granite, which are associated with W-Sn-Mo-Be-F mineralization. Zircon U-Pb ages, major and trace elements, mineral chemical and Hf isotopic compositions of the W-Sn-bearing granites from the Piaoac District have been investigated in detail. LA-ICP-MS U-Pb dating of zircon grains from these granites yielded ages of 82.5±2.3 and 82±1.8 Ma, representing an episode of Late Cretaceous magmatic event. These granites are characterized by high peraluminous and have typical S-type geochemical signatures with high SiO_2(72.37 wt.%–73.07 wt.%), high A/CNK values(1.61–1.65) and Al_2O_3(14.4 wt.%–15 wt.%). They are enriched in Rb, U, K, Th, Ta and Pb and display pronounced negative Ba, Sr, Nb, Ti and Eu(Eu/Eu*=0.19–0.24) anomalies. The high degree of fractional crystallization is characterized by low Rb, Sr, Ba and Eu concentrations with high ratios of La/Sm and Eu/Eu*. Zircon grains show εHf(t) values from-9.69 to-0.9 and the corresponding TDM2 range from 1.2 to 1.7 Ga, indicating that these granites could be derived from the Proterozoic basement rocks with minor input from mantle-derived magmas. The calculation of Fe^(3+) and Fe^(2+) of biotites indicates a low oxygen fugacity condition(log fO_2 ranging from 10-17 to 10-18 bars, below MH), which is favorable for the W-Sn mineralization. Tungsten and tin have been enriched in granitic magmas through fractionation, and low oxygen fugacity conditions have promoted the accumulation and transportation of W-Sn in the hydrothermal fluids, leading to deposition of mineral phases. The geochemical data suggest that Piaoac granites formed in an extensional setting related with the Late Cretaceous magmatism occurring large-scale lithospheric extensional in South China Block.展开更多
Flotation is an efficient pre-treatment technology for oily water.In this work,the interaction process between the moving oil droplet and the gas bubble was studied by high-speed camera and Bassset-Boussinesq-Oseen(BB...Flotation is an efficient pre-treatment technology for oily water.In this work,the interaction process between the moving oil droplet and the gas bubble was studied by high-speed camera and Bassset-Boussinesq-Oseen(BBO)theoretical model,and the experimental and simulation results of the oil droplet trajectory were compared.Moreover,the micro-particle image velocimetry system was utilized to observe the flow inside and outside of the moving oil droplet.The results show that the BBO model with the mobile bubble’s surface can reflect the velocity change trend of the oil droplet during the interaction process between the moving oil droplet and the gas bubble,but there are some significant differences between the experimental and simulation results.While the oil droplet is moving on the bubble’s surface,the velocity of the area near the contact point of oil droplet–gas bubble is less than that of the other areas inside the oil droplet.Meanwhile,the flow of water above the oil drop is more biased towards the gas bubble.展开更多
Phenolic wastewater is one of the priorities in the field of wastewater treatment,which poses a serious threat to the human health and nature environment.In this paper,cationic cetyltrimethylammonium bromide(CTAB)and ...Phenolic wastewater is one of the priorities in the field of wastewater treatment,which poses a serious threat to the human health and nature environment.In this paper,cationic cetyltrimethylammonium bromide(CTAB)and anionic sodium oleate(Na OL)microemulsions were utilized to extract phenol from the wastewater.The optimal extraction factors were investigated by exploring the effects of microemulsion composition ratio and extraction conditions on the phenol extraction performance.Furthermore,the enhanced extraction mechanism of phenol by cations microemulsions is illustrated by studying the extraction process of cationic and anionic microemulsions in the extraction of phenol.The optimum components were obtained:surfactant concentration of 0.2 mol·L^(-1),isoamyl alcohol volume of 30%,internal aqueous phase concentration of CTAB microemulsion of 0.05 mol·L^(-1),and internal aqueous phase concentration of Na OL microemulsion of 0.09 mol·L^(-1).The extraction efficiencies were 96.44%and 82.0%when using CTAB and Na OL microemulsions under optimal conditions(water-emulsion ratio of 5,contact time of 9 min,extraction temperature of 298.15 K,and p H of 9),confirming the enhanced extraction of phenol by CTAB cationic microemulsion.It was analyzed that the enhanced extraction of CTAB microemulsion was due to the electrostatic adsorption of cations with phenol root ions.展开更多
Some Au deposits in southern Anhui Province have recently been found to be closely associated with Late Mesozoic intrusions. Typical examples include the Huashan Au(Sb) deposit and Au deposits at Zhaojialing, Wuxi,and...Some Au deposits in southern Anhui Province have recently been found to be closely associated with Late Mesozoic intrusions. Typical examples include the Huashan Au(Sb) deposit and Au deposits at Zhaojialing, Wuxi,and Liaojia. In order to understand the mechanisms that led the formation of these Au deposits, we make detailed reviews on the geological characteristics of these Au deposits. Specifically, we present new LA-ICP-MS zircon U–Pb dating, along with elemental and Hf isotopic data from the Huashan Au(Sb) deposit. Our data suggests that the Huashan ore-related intrusions were emplaced during the Late Jurassic and Early Cretaceous periods(144–148 Ma). They are characterized by arc-magma features and high oxygen fugacity and are rich in inherited zircons. Zircon U–Pb ages and Lu–Hf isotopes from intrusions suggest that Proterozoic juvenile lithosphere is the main source of these intrusions. The regional geological history implies that lithosphere beneath southern Anhui was produced during a Proterozoic subduction and was fertilized with Au(Cu) in the process. Integrated with theresults of previous studies, we inferred that Late Mesozoic intrusions formed by the remelting of the lithosphere could provide the metal endowment for the Au-rich deposits in southern Anhui.展开更多
Inhalable particle is a harmful air pollutant that causes a significant threat to people's health and ecological environments,which should be removed to purify air,but there exists limited removal efficiency due t...Inhalable particle is a harmful air pollutant that causes a significant threat to people's health and ecological environments,which should be removed to purify air,but there exists limited removal efficiency due to particle re-entrainment.Here,Operando observation system based on microscopic visualization method is developed to make in situ test of particle migration,deposition and re-entrainment characteristics on a lab-on-a-chip to achieve the investigation in micro-level scale.The deposition evolution of charged particles is recorded in electric field region intuitively,which confirms the fracture of particle chain occurs during the growth process of deposited particles.It captures the instantaneous process that a larger particle with micron size due to the coagulation of submicron particles fractures from main body of the particle chain for the first time.The analysis of migration behavior of a single submicron particle near electrode surface demonstrates the direct influence of drag force on the fracture of particle chain.This work is the first-time visualization of dynamic process and mechanism elucidation of particle re-entrainment at the micron level,and the findings will provide the theory support for the particle re-entrainment mechanism and bring inspires of enhancing capture efficiency of inhalable particle.展开更多
Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of MOCJMs.Herein,the flow cha...Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of MOCJMs.Herein,the flow characteristics and micromixing performance inside the MOCJM were investigated using experiments and computational fluid dynamics(CFD)simulations based on the Villermaux/Dushman system and the finite-rate/modified eddy-dissipation model.The optimal A value was correlated with the characteristic parameters of MOCJMs to develop a CFD calculation method applicable to the study of the micromixing performance of the MOCJMs.Then the micromixing efficiency was evaluated using the segregation index XS,and the effects of operational and geometric parameters such as mixing flow Reynolds number(ReM),flow ratio(RF),total jet area(ST),the number of jet orifices(n),and outlet configuration on the micromixing efficiency were investigated.It was found that the intensive turbulent region generated by interactions between jets,as well as between jets and crossflows,facilitated rapid reactions.XS decreased with increasing ReM and decreasing RF.Furthermore,MOCJMs with lower ST,four jet orifices,and the narrower outlet configuration demonstrated a better micromixing efficiency.This study contributes to a deeper understanding of the micromixing performance of MOCJMs and provides valuable guidance for their design,optimization,and industrial application.展开更多
Seamounts on the drifting oceanic crust are inevitably carried by plate motions and eventually accreted or subducted.However,the geochemical signatures of the subducted seamounts and the significance of seamount subdu...Seamounts on the drifting oceanic crust are inevitably carried by plate motions and eventually accreted or subducted.However,the geochemical signatures of the subducted seamounts and the significance of seamount subduction are not well constrained.Hundreds of seamounts have subducted beneath the Philippine Sea Plate following the westward subduction of the Pacific Plate since the Eocene(~52 Ma).The subducted oceanic crust and seamount materials can be exhumed from the mantle depth to the seafloor in the Mariana forearc region by serpentinite mud volcanoes,providing exceptional opportunities to directly study the subducted oceanic crust and seamounts.The International Ocean Discovery Program(IODP)expedition 366 has recovered a few metamorphosed mafic clasts exhumed from the Mariana forearc serpentinite mud volcanoes,e.g.,the Fantangis?a and Asùt Tesoru seamounts.These mafic clasts have tholeiitic to alkaline affinities with distinct trace elements and Nd-Hf isotopes characteristics,suggesting different provenances and mantle sources.The tholeiites from the Fantangisna Seamount have trace element characteristics typical of mid-ocean ridge basalt.The Pacific-type Hf-Nd isotopic compositions,combined with the greenschist metamorphism of these tholeiites further suggest that they came from the subducted Pacific oceanic crust.The alkali basalts-dolerites from the Fantangisna and Asùt Tesoru seamounts show ocean island basalt(OIB)-like geochemical characteristics.The OIB-like geochemical signatures and the low-grade metamorphism of these alkali basalts-dolerites suggest they came from subducted seamounts that originally formed in an intraplate setting on the Pacific Plate.The Pacific Plate origin of these metabasites suggests they were formed in the Early Cretaceous or earlier.Two types of OIBs have been recognized from alkali metabasites,one of which is geochemically similar to the HIMU-EMI-type OIBs from the West Pacific Seamount Province,and another is similar to the EMII-type OIBs from the Samoa Island in southern Pacific,with negative Nb-Ta-Ti anomalies and enriched Nd-Hf isotopes.Generally,these alkali metabasites are sourced from the heterogeneous mantle sources that are similar to the present South Pacific Isotopic and Thermal Anomaly.This study provides direct evidence for seamount subduction in the Mariana convergent margins.We suggest seamount subduction is significant to element cycling,mantle heterogeneity,and mantle oxidation in subduction zones.展开更多
The Southwest Borneo(SW Borneo)block belongs to Sundaland and is the oldest continental fragment of Borneo that is believed to derive from the Gondwana land.The U-Pb isotopic dating ages of 113 detrital zircons from s...The Southwest Borneo(SW Borneo)block belongs to Sundaland and is the oldest continental fragment of Borneo that is believed to derive from the Gondwana land.The U-Pb isotopic dating ages of 113 detrital zircons from sandstones of the Ketapang Complex in SW Borneo range from 3298 Ma to 78 Ma,and show six major age populations:2476-2344 Ma,2016-1831 Ma,1296-759 Ma,455-406 Ma,262-210 Ma,and 187-78 Ma.The youngest age of these detrital zircons is 78 Ma,indicating that the maximum depositional age of the sandstones is Campanian.Permian-Late Cretaceous detrital zircons are interpreted as having been derived from the nearby Schwaner Mountains and the Permian-Triassic tin belt granitoids in Southeast Asia(SE Asia).Archean-Carboniferous detrital zircons have a continental Gondwana provenance,with their age spectra similar to those of northwestern Australia,indicating that these zircons could be derived from the orogenic belts and cratons in northwestern and central Australia.The provenance of these detrital zircons in this study indicates the SW Borneo block was located on the northwestern margin of Australia during the Paleozoic,in the region of the Banda Embayment.SW Borneo rifted from Australia and moved northward in the Early Jurassic,and this block was added to Sundaland in the Early Cretaceous.The Luconia-Dangerous Grounds continental fragment derived from East Asia collided with SW Borneo after subduction in the Cretaceous,which induced the widespread magmatism in the Schwaner Mountains in SW Borneo.展开更多
Uranium exploration especially in currently non-producing countries like Nigeria possesses high economic prospect. This study investigates a new uranium prospect in Mika, Northeastern Nigeria. The Mika uranium mineral...Uranium exploration especially in currently non-producing countries like Nigeria possesses high economic prospect. This study investigates a new uranium prospect in Mika, Northeastern Nigeria. The Mika uranium mineralization is located in Mika, Taraba State. Two lodes were identified and additional nine (9) trenches were added. The main lode in the west extends about 10 m, ore vein strikes 348°, inclination 42°and the strike of the lode 306°with average uranium content of 18%. The eastern trench is about 8 × 4 × 6 m which exposes a veinlet of pitchblende. From the petrography, one can deduce that the granitic host rock has suffered deformation resulting in crushing of quartz crystals and stretching of plagioclase. The uraninite and chalcedony in the late phase filled up the fractures along the crystal grain boundaries as veinlets. The laboratory gamma ray analysis of the samples showed that the secondary uranium content is 0.1%, while the primary uranium ore grade is 1.5%. Radiometric in situ measurements showed that Th and K ranges from 47.3 - 3654 ppm and 4.26% - 6.26% respectively. From the survey, a strong radiometric zone extends 800 × 35 m in an NW-SE direction and has highest radiation content of 1200 cpm against the background count rate of 30 cpm. Generally, the uranium concentrations in the ores in Mika area range from 0.03% - 0.12%. Since only the surface occurrences have been explored, the study area is a good prospect for future development when properly explored. The North-eastern Nigeria has been roughly explored by Nigeria Uranium Mining Company (NUMCO) in 1980, but no formal exploration had been followed after that, especially near the site of this article. The company (ACE Mines, Ltd) of the first author was among the few uranium mining companies approved in the list of Nigerian Geological Survey agency of Abuja in Nigeria. The authors determined the coordinates of the site in their first survey which formed the prospect area in the licence.展开更多
The Boloven bauxite deposit occurs either in the weathered basalt(alkali basalt and tholeiite), or in the Cretaceous sandstone. It is generally agreed that the bauxite deposits/laterites overlying the alkali basalt an...The Boloven bauxite deposit occurs either in the weathered basalt(alkali basalt and tholeiite), or in the Cretaceous sandstone. It is generally agreed that the bauxite deposits/laterites overlying the alkali basalt and tholeiite were derived from weathering of underlying basalt, however, the origin of bauxite deposit overlying the sandstone remains controversial. Chondrite-normalized REE patterns show that the bauxite ores/laterites overlying the sandstone exhibit quite similar chondrite-normalized REE patterns to those overlying the alkali basalt. Diagram of Al-Ti-Zr shows that the bauxite ores/laterites overlying the sandstone, tholeiite and alkali basalt are close to each other and to the calc-alkaline suite, however, significantly different from the sandstone and shales. Binary diagram of log Nb/Y vs log Zr/Ti further indicates that the parent rocks of bauxite ores/laterites overlying the sandstone belong to the suit of ultra-alkali to alkali basalt. Multivariate statistical analysis of geochemical data exhibit that the geochemical characteristics of HREE, Y, LREE and Al_2O_3 for bauxite ores/laterites overlying the sandstone are similar to those overlying the alkali basalt(15.7 Ma), obviously different from those overlying the tholeiite(1.2 to 0.5 Ma). Consequently, it can be inferred that the bauxite deposits/laterites overlying the sandstone were derived from the alkali basalt.展开更多
This study delves into the intricate deposition dynamics of submicron particles within electric-flow coupled fields,underscoring the unique challenges posed by their minuscule size,aggregation tendencies,and biologica...This study delves into the intricate deposition dynamics of submicron particles within electric-flow coupled fields,underscoring the unique challenges posed by their minuscule size,aggregation tendencies,and biological reactivity.Employing an operando investigation system that synergizes microfluidic technology with advanced micro-visualization techniques within a lab-on-a-chip framework enables a meticulous examination of the dynamic deposition phenomena.The incorporation of object detection and deep learning methodologies in image processing streamlines the automatic identification and swift extraction of crucial data,effectively tackling the complexities associated with capturing and mitigating these hazardous particles.Combined with the analysis of the growth behavior of particle chain under different applied voltages,it established that a linear relationship exists between the applied voltage and θ.And there is a negative correlation between the average particle chain length and electric field strength at the collection electrode surface(4.2×10^(5)to 1.6×10^(6)V·m^(-1)).The morphology of the deposited particle agglomerate at different electric field strengths is proposed:dendritic agglomerate,long chain agglomerate,and short chain agglomerate.展开更多
Loop-mediated isothermal amplification(LAMP)is a novel nucleic acid amplification method.Compared with the widely utilized polymerase chain reaction(PCR),LAMP has higher speed and efficiency as well as lower requireme...Loop-mediated isothermal amplification(LAMP)is a novel nucleic acid amplification method.Compared with the widely utilized polymerase chain reaction(PCR),LAMP has higher speed and efficiency as well as lower requirement for system temperature control because the whole amplification process is isothermal and no efforts are needed to switch between different temperatures.In this paper,we designed and fabricated different kinds of polycarbonate(PC)microfluid chips,explored appropriate reaction condition for LAMP in microenvironment(1 nL→10μL),and developed a microfluidic isothermal amplification detection system.The DNA optimal amplification temperature is obtained;the starting time of exponential amplification of DNA is put forward farther.The optimal condition of DNA amplification in microenvironment,with a little reaction materials and early starting exponential amplification time of DNA are very important for clinic DNA detection and the application of Lab-on-a-Chip.展开更多
A surface plasmon resonance imaging(SPRI)system was developed for the discrimination of proteins on a gold surface.As a label-free and high-throughput technique,SPRI enables simultaneously monitoring of the biomolecul...A surface plasmon resonance imaging(SPRI)system was developed for the discrimination of proteins on a gold surface.As a label-free and high-throughput technique,SPRI enables simultaneously monitoring of the biomolecular interactions at low concentrations.We used SPRI as a label-free and parallel method to detect different proteins based on protein microarray.Bovine Serum Albumin(BSA),Casein and Immunoglobulin G(IgG)were immobilized onto the Au surface of a gold-coated glass chip as spots forming a 6×6 matrix.These proteins can be discriminated directly by changing the incident angle of light.Excellent reproducibility for label-free detection of protein molecules was achieved.This SPRI platform represents a simple and robust method for performing high-sensitivity detection of protein microarray.展开更多
Symmetry plays a fundamental role in topological photonic crystals, and topological phase transitions induced bydisorder have also been extensively explored in recent years. However, in this work, we find anisotropy c...Symmetry plays a fundamental role in topological photonic crystals, and topological phase transitions induced bydisorder have also been extensively explored in recent years. However, in this work, we find anisotropy can beinduced by reducing symmetry in a C_(2v) symmetry triangular photonic crystal. We investigate that anisotropyinducedinterfaces profoundly affect edge states and enable the realization of slow light dispersion. Numericalsimulations reveal a transition from gapless chiral edge modes to gapped flat band dispersion. Furthermore, weobserve higher-order corner states in corner structures constructed by anisotropic interfaces. The corner states canbe induced and localized at different lattice positions, thereby realizing multiple types of higher-order topologicalstates. We demonstrate the significance of anisotropic geometry in topological photonics. These findings opennew possibilities for steering wave transport in multiple dimensions and offer, to our knowledge, a novel researchperspective on the transformation of topological states induced by anisotropic lattices.展开更多
The identification of complete ammonia oxidizers(comammox)within the nitriteoxidizing bacteria(NOB)genus Nitrospira,capable of oxidizing ammonia directly to nitrite and nitrate,represents a pivotal advancement in eluc...The identification of complete ammonia oxidizers(comammox)within the nitriteoxidizing bacteria(NOB)genus Nitrospira,capable of oxidizing ammonia directly to nitrite and nitrate,represents a pivotal advancement in elucidating the microbial and metabolic pathways underlying nitrification in the global nitrogen cycle.Although comammox Nitrospira have been consistently identified across diverse environmental habitats,their rapid enrichment from complex activated sludge systems remains challenging owing to their intrinsically low growth rates and the restricted availability of cultured isolates.In this study,Candidatus Nitrospira inopinata(Ca.N.inopinata)was successfully enriched from anammox-inoculated sludge within 70 d under low ammonia concentrations(~4.88 mg/L),ambient temperatures(21.6-28.4℃),and minimal aeration(0-0.01 mg/L),facilitated by the application of kanamycin(KAN).By employing 16S rRNA gene amplicon sequencing and quantitative polymerase chain reaction(qPCR)targeting the functional marker gene amoA,Ca.N.inopinata was identified as the dominant ammonia oxidizer,achieving a relative abundance of 95.22% in the nitrifying community.Kanamycin was shown to exert significant selective pressure,further enhancing the enrichment of Ca.N.inopinata.These findings demonstrate the feasibility of establishing comammox Nitrospira through direct inoculation of anammox pellets coupled with kanamycin,offering a robust and efficient strategy for rapid enrichment of comammox Nitrospira for biotechnological applications,while underscoring the energy-efficient advantages of comammox-driven ammonia oxidation processes.展开更多
基金supported by the National Key R&D Program Project of China(No.2016YFC0600209)。
文摘The Nanling-Xuancheng ore region of Anhui Province is located in the Middle-Lower Yangtze River metallogenic belt.Insufficient exploration and research have been carried out in this newly defined ore district,although the Chating large porphyry Cu-Au deposit and a few middle-sized skarntype Cu polymetallic deposits have been discovered.In this study,we carried out high-resolution seismic reflection,magnetotelluric,gravity,and magnetic investigations,and constructed the 3 D geological structure of the uppermost crust in a depth range of 0-5 km using a comprehensive inversion of the new data constrained by previous deep-drilling data.We hence proposed some new insights to understand the mineralization processes of this district.A system of alternating ridges and valleys is suggested as the major structure pattern,composed of“two-layer structure”of the basins and“three-layer structure”of anticlines.Moreover,a conjugated fault system and its distribution features are revealed in our models,including the Jiangnan fault,Zhouwang fault,and Kunshan thrust nappe.The Jiangnan and Kunshan faults are suggested to have controlled the diagenesis and metallogenesis.Two deep concealed plutons located in Chating and Magushan are found,forming the Mesozoic diorite-felsic intrusions.These intrusions are believed to be the causes of hydrothermal deposits such as the Chating deposit and the Magushan deposit.
基金the State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang(No.2020Z03)the National Key R&D Program of China(Nos.2016YFC0600408,2019YFA0708400)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB41020102)。
文摘The Early Cretaceous aluminous A-type granites in the Lower Yangtze River belt(LYRB)can provide important insights into the Mesozoic magmatism in eastern China,but their origin remains highly controversial.In this study,radiogenic Ca-Nd isotopic analysis was performed for syenite porphyry and alkali-feldspar granite porphyry of the Yangshan pluton,a typical aluminous A-type granitic intrusion in the LYRB,to constrain its source and geodynamic setting.The results show thatε_(Ca)(126 Ma),ε_(Nd)(126 Ma)and K/Ca_(source) of the syenite porphyry range from-0.24 to+0.96,-7.2 to-6.0,and 0.31 to 1.26,respectively.The corresponding values for the alkali-feldspar granite porphyry range from 0.26 to 0.84,-8.0 to-6.1,and 0.79 to 1.08,respectively.Binary mixing modeling indicates that they were originated from the same sources with different proportion,namely,a mixing of 50%to 75%Neoproterozoic crust and 50%to 25%asthenospheric mantle.Together with previous works,we propose that the Early Cretaceous subduction of the ridge between the Pacific and Izanagi plates was responsible for the formation of the aluminous A-type granites in the LYRB.
基金financially supported by the National Natural Science Foundation of China(No.42472117)China Geological Survey(Nos.DD20243431,DD20230342,DD20240064)。
文摘0.INTRODUCTION.The Jiuwandashan Sn-polymetallic ore cluster,located in the western part of the Jiangnan Orogen and the Nanling Metallogenic Belt,is one of the most significant Precambrian tin ore concentration areas in South China(Figure 1a;Mao et al.,1987).Recently,this region has garnered considerable research attention due to its intense mafic-felsic magmatic activity and large-scale Sn-polymetallic mineralization(Li et al.,2020;Chen J F et al.,2019;Huang and Wang,2019;Zhang et al.,2019;Chen L et al.,2018;Xiang et al.,2018;Su et al.,2014).A series of medium-to large-scale Sn-polymetallic deposits,including Jiumao,Liuxiu,Yidong,Honggangshan,and Shaping(Figure 1b),have been identified within this region,with proven tin reserves of approximately 200000 t.High-precision dating methods have yielded cassiterite U-Pb ages of ca.830 Ma,pointing to a Neoproterozoic Sn-polymetallic mineralization event in South China(Zhang et al.,2019;Xiang et al.,2018).
基金financially supported by the Natural Science Foundation of China (Nos. 41573039 41673040 U1603245)
文摘The paper presents an overview of the relationships between the interior structures of tectonic terranes and the distribution of tectonic-metallogenic zones in Southeast Asia. Episodic tectonic activities occurred in this archipelagic area, generating metallogenic belts in multi-terranes. Since the Late Paleozoic, opening and closure of the Paleotethys and Neotethys led to multiple suture zones between different blocks, mainly between the Indochina terrane, the Nambung terrane, the Sibumasu terrane and the West Myanmar terrane. During the Mesozoic to Cenozoic, the formation of accreted terranes and their related islands was caused by subduction and collision processes between the Pacific and Australian plates toward the Eurasian Continent, forming Sundaland and its affiliated islands, the Philippines and its subsidiary islands, the Papua New Guinea terrane and its related islands and the Sunda epicontinental arc system. Within the margin of terranes resulted in the structural transfer zones, their secondary tectonic units can be divided into island arc belts, back-arc basins, suture zones, marginal fold belts and orogenic belts. The metallogenic assemblages are mainly distributed within these structural zones of the terranes. According to the relationship between these tectonic units and the distribution of mineral resources, the tectonic-metallogenic belts can be divided into 24 metallogenic belts in Southeast Asia. They are characterized by a diversity and frequency of metallogenic material combination which is likely to reflect the complexity of the material distribution during mineralization processes, mostly by the structural transformation during the dissociation-convergence process between multiple terranes. Therefore, the formation of ore deposits was not only restricted by the evolution(opening and closure) of Paleo-and Neotethys, but may also be controlled by the interaction of the terranes with different tectonic attributes which provided multiple sources of metallogenic material.
基金supported by National Program on Key Basic Research Project (973 Program) (2015CB453002)DREAM Project of MOST China (2016YFC0600404)CASTWAS President Fellowship 2012
文摘Recently measured high gamma ray values in the Yanchang Formation of the Upper Triassic in the Ordos Basin have added an interesting and controversial twist to the study of the formation’s uranium enrichment and genesis.High uranium and thorium contents in the tuffaceous layer cause high gamma ray values in the Yanchang Formation.Petrographic studies,major elements,rare earth elements(REEs),and trace elements have been systematically analyzed to determine the composition,geochemical environment,and diagenetic processes of the layer.The observed color of the tuffaceous layer in the study area varies from yellow to yellowish brown.The tuff consists of matrix supported with sub-rounded to sub-angular lithic fragments.These lithic fragments probably derived from pre-existing rocks and incorporated into the tuffaceous layer during volcanic eruption.Quartz,plagioclase,and biotite were observed in well to poorly sorted form,in addition to framboidal pyrite and organic laminae.Measured ratios of SiO_2/Al_2O_3 ranged from 3.277 to 6.105 with an average of 3.738.The ratio of TiO_2/Al_2O_3 varied from 0.037 to 0.201 with an average of 0.061,indicating that the sediments of the tuffaceous layer originated from an intermediate magma.REE distribution patterns show sharp negative Eu anomalies,indicating a reducing environment,which is suitable for uranium deposition.A reducing environment was confirmed by black shale in the base of the Yanchang Formation.Such black shale has high organic matter content that can take kerogene from mudstone and provide a reducing environment for uranium enrichment in the tuffaceous layer.Moreover,negative Eu anomalies and the REE patterns indicate a subduction-related volcanic arc environment as the magma source of the tuffaceous layers.High values of Rb,Ba,and Sr might be the result of fluid phase activities;low values of Hf and Eu indicate the involvement of crustal material during diagenesis of the tuff.Discrimination diagrams(Th/Yb vs Ta/Yb,Th/Hf vs Ta/Hf)suggest an active continental margin as the tectonic setting of source volcanoes.Plots of Nb versus Y,Rb versus Y+Nb,TiO_2 versus Zr,and Th/Yb versus Nb/Yb of the tuffaceous content point to calc-alkaline continental arc-related magmatism.We concluded that uranium enrichment in the tuffaceous layer was supported by oxidation–reduction.
基金supported by the National Key R & D Program of China (No. 2016YFC0600404)the National Natural Science Foundation of China (Nos. 41673040 and 41611540339)
文摘Piaoac granites exposed in the Cao Bang region, northern Vietnam, are S-type granite, which are associated with W-Sn-Mo-Be-F mineralization. Zircon U-Pb ages, major and trace elements, mineral chemical and Hf isotopic compositions of the W-Sn-bearing granites from the Piaoac District have been investigated in detail. LA-ICP-MS U-Pb dating of zircon grains from these granites yielded ages of 82.5±2.3 and 82±1.8 Ma, representing an episode of Late Cretaceous magmatic event. These granites are characterized by high peraluminous and have typical S-type geochemical signatures with high SiO_2(72.37 wt.%–73.07 wt.%), high A/CNK values(1.61–1.65) and Al_2O_3(14.4 wt.%–15 wt.%). They are enriched in Rb, U, K, Th, Ta and Pb and display pronounced negative Ba, Sr, Nb, Ti and Eu(Eu/Eu*=0.19–0.24) anomalies. The high degree of fractional crystallization is characterized by low Rb, Sr, Ba and Eu concentrations with high ratios of La/Sm and Eu/Eu*. Zircon grains show εHf(t) values from-9.69 to-0.9 and the corresponding TDM2 range from 1.2 to 1.7 Ga, indicating that these granites could be derived from the Proterozoic basement rocks with minor input from mantle-derived magmas. The calculation of Fe^(3+) and Fe^(2+) of biotites indicates a low oxygen fugacity condition(log fO_2 ranging from 10-17 to 10-18 bars, below MH), which is favorable for the W-Sn mineralization. Tungsten and tin have been enriched in granitic magmas through fractionation, and low oxygen fugacity conditions have promoted the accumulation and transportation of W-Sn in the hydrothermal fluids, leading to deposition of mineral phases. The geochemical data suggest that Piaoac granites formed in an extensional setting related with the Late Cretaceous magmatism occurring large-scale lithospheric extensional in South China Block.
基金supported by the National Natural Science Foundation of China(51578239)the Education and Scientific Research Projects of Shanghai(17DZ1202802)。
文摘Flotation is an efficient pre-treatment technology for oily water.In this work,the interaction process between the moving oil droplet and the gas bubble was studied by high-speed camera and Bassset-Boussinesq-Oseen(BBO)theoretical model,and the experimental and simulation results of the oil droplet trajectory were compared.Moreover,the micro-particle image velocimetry system was utilized to observe the flow inside and outside of the moving oil droplet.The results show that the BBO model with the mobile bubble’s surface can reflect the velocity change trend of the oil droplet during the interaction process between the moving oil droplet and the gas bubble,but there are some significant differences between the experimental and simulation results.While the oil droplet is moving on the bubble’s surface,the velocity of the area near the contact point of oil droplet–gas bubble is less than that of the other areas inside the oil droplet.Meanwhile,the flow of water above the oil drop is more biased towards the gas bubble.
基金sponsored by the National Natural Science Foundation of China(22225804)Shanghai Sailing Program,China(21YF1409500)+1 种基金the National Natural Science Foundation of China(22078102)the Education and Scientific Research Projects of Shanghai,China(19DZ1208201)。
文摘Phenolic wastewater is one of the priorities in the field of wastewater treatment,which poses a serious threat to the human health and nature environment.In this paper,cationic cetyltrimethylammonium bromide(CTAB)and anionic sodium oleate(Na OL)microemulsions were utilized to extract phenol from the wastewater.The optimal extraction factors were investigated by exploring the effects of microemulsion composition ratio and extraction conditions on the phenol extraction performance.Furthermore,the enhanced extraction mechanism of phenol by cations microemulsions is illustrated by studying the extraction process of cationic and anionic microemulsions in the extraction of phenol.The optimum components were obtained:surfactant concentration of 0.2 mol·L^(-1),isoamyl alcohol volume of 30%,internal aqueous phase concentration of CTAB microemulsion of 0.05 mol·L^(-1),and internal aqueous phase concentration of Na OL microemulsion of 0.09 mol·L^(-1).The extraction efficiencies were 96.44%and 82.0%when using CTAB and Na OL microemulsions under optimal conditions(water-emulsion ratio of 5,contact time of 9 min,extraction temperature of 298.15 K,and p H of 9),confirming the enhanced extraction of phenol by CTAB cationic microemulsion.It was analyzed that the enhanced extraction of CTAB microemulsion was due to the electrostatic adsorption of cations with phenol root ions.
基金supported by the National Key R&D Program of China(No.2016YFC0600404)the National Natural Science Foundation of China(Nos.41372087,41673040,41174043)the Project of Geological Science and Technology of Anhui Province(2014-K-04,2016-K-1)
文摘Some Au deposits in southern Anhui Province have recently been found to be closely associated with Late Mesozoic intrusions. Typical examples include the Huashan Au(Sb) deposit and Au deposits at Zhaojialing, Wuxi,and Liaojia. In order to understand the mechanisms that led the formation of these Au deposits, we make detailed reviews on the geological characteristics of these Au deposits. Specifically, we present new LA-ICP-MS zircon U–Pb dating, along with elemental and Hf isotopic data from the Huashan Au(Sb) deposit. Our data suggests that the Huashan ore-related intrusions were emplaced during the Late Jurassic and Early Cretaceous periods(144–148 Ma). They are characterized by arc-magma features and high oxygen fugacity and are rich in inherited zircons. Zircon U–Pb ages and Lu–Hf isotopes from intrusions suggest that Proterozoic juvenile lithosphere is the main source of these intrusions. The regional geological history implies that lithosphere beneath southern Anhui was produced during a Proterozoic subduction and was fertilized with Au(Cu) in the process. Integrated with theresults of previous studies, we inferred that Late Mesozoic intrusions formed by the remelting of the lithosphere could provide the metal endowment for the Au-rich deposits in southern Anhui.
基金supported by the National Natural Science Foundation of China (Nos.52200130 and 22176123)Postdoctoral Science Foundation of China (No.2022M722082)the National Key Research&Development Plan (No.2017YFC0211804)。
文摘Inhalable particle is a harmful air pollutant that causes a significant threat to people's health and ecological environments,which should be removed to purify air,but there exists limited removal efficiency due to particle re-entrainment.Here,Operando observation system based on microscopic visualization method is developed to make in situ test of particle migration,deposition and re-entrainment characteristics on a lab-on-a-chip to achieve the investigation in micro-level scale.The deposition evolution of charged particles is recorded in electric field region intuitively,which confirms the fracture of particle chain occurs during the growth process of deposited particles.It captures the instantaneous process that a larger particle with micron size due to the coagulation of submicron particles fractures from main body of the particle chain for the first time.The analysis of migration behavior of a single submicron particle near electrode surface demonstrates the direct influence of drag force on the fracture of particle chain.This work is the first-time visualization of dynamic process and mechanism elucidation of particle re-entrainment at the micron level,and the findings will provide the theory support for the particle re-entrainment mechanism and bring inspires of enhancing capture efficiency of inhalable particle.
基金the financial support from the Shanghai Sailing Program,China(21YF1409500)the National Natural Science Foundation of China(22308100,22308105)+1 种基金the State Key Laboratory of Chemical Engineering(SKL-ChE-23Z01)the National Science Fund for Distinguished Young Scholars of China(22225804).
文摘Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of MOCJMs.Herein,the flow characteristics and micromixing performance inside the MOCJM were investigated using experiments and computational fluid dynamics(CFD)simulations based on the Villermaux/Dushman system and the finite-rate/modified eddy-dissipation model.The optimal A value was correlated with the characteristic parameters of MOCJMs to develop a CFD calculation method applicable to the study of the micromixing performance of the MOCJMs.Then the micromixing efficiency was evaluated using the segregation index XS,and the effects of operational and geometric parameters such as mixing flow Reynolds number(ReM),flow ratio(RF),total jet area(ST),the number of jet orifices(n),and outlet configuration on the micromixing efficiency were investigated.It was found that the intensive turbulent region generated by interactions between jets,as well as between jets and crossflows,facilitated rapid reactions.XS decreased with increasing ReM and decreasing RF.Furthermore,MOCJMs with lower ST,four jet orifices,and the narrower outlet configuration demonstrated a better micromixing efficiency.This study contributes to a deeper understanding of the micromixing performance of MOCJMs and provides valuable guidance for their design,optimization,and industrial application.
基金financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(XDA22050103,XDB42020303,XDB18020102)the National Natural Science Foundation of China(Grant No.41803002)+2 种基金China Postdoctoral Science Foundation(No.2018 M642708)the Qingdao National Laboratory for Marine Science and Technology(2017ASKJ02)the Taishan Scholar Foundation of Shandong Province(ts201712075)。
文摘Seamounts on the drifting oceanic crust are inevitably carried by plate motions and eventually accreted or subducted.However,the geochemical signatures of the subducted seamounts and the significance of seamount subduction are not well constrained.Hundreds of seamounts have subducted beneath the Philippine Sea Plate following the westward subduction of the Pacific Plate since the Eocene(~52 Ma).The subducted oceanic crust and seamount materials can be exhumed from the mantle depth to the seafloor in the Mariana forearc region by serpentinite mud volcanoes,providing exceptional opportunities to directly study the subducted oceanic crust and seamounts.The International Ocean Discovery Program(IODP)expedition 366 has recovered a few metamorphosed mafic clasts exhumed from the Mariana forearc serpentinite mud volcanoes,e.g.,the Fantangis?a and Asùt Tesoru seamounts.These mafic clasts have tholeiitic to alkaline affinities with distinct trace elements and Nd-Hf isotopes characteristics,suggesting different provenances and mantle sources.The tholeiites from the Fantangisna Seamount have trace element characteristics typical of mid-ocean ridge basalt.The Pacific-type Hf-Nd isotopic compositions,combined with the greenschist metamorphism of these tholeiites further suggest that they came from the subducted Pacific oceanic crust.The alkali basalts-dolerites from the Fantangisna and Asùt Tesoru seamounts show ocean island basalt(OIB)-like geochemical characteristics.The OIB-like geochemical signatures and the low-grade metamorphism of these alkali basalts-dolerites suggest they came from subducted seamounts that originally formed in an intraplate setting on the Pacific Plate.The Pacific Plate origin of these metabasites suggests they were formed in the Early Cretaceous or earlier.Two types of OIBs have been recognized from alkali metabasites,one of which is geochemically similar to the HIMU-EMI-type OIBs from the West Pacific Seamount Province,and another is similar to the EMII-type OIBs from the Samoa Island in southern Pacific,with negative Nb-Ta-Ti anomalies and enriched Nd-Hf isotopes.Generally,these alkali metabasites are sourced from the heterogeneous mantle sources that are similar to the present South Pacific Isotopic and Thermal Anomaly.This study provides direct evidence for seamount subduction in the Mariana convergent margins.We suggest seamount subduction is significant to element cycling,mantle heterogeneity,and mantle oxidation in subduction zones.
基金Supported by the National Natural Science Foundation of China(Nos.41803038,41903005)the Guangxi Natural Science Foundation(No.2018GXNSFAA138193)the China Postdoctoral Science Foundation(No.2019M662458)。
文摘The Southwest Borneo(SW Borneo)block belongs to Sundaland and is the oldest continental fragment of Borneo that is believed to derive from the Gondwana land.The U-Pb isotopic dating ages of 113 detrital zircons from sandstones of the Ketapang Complex in SW Borneo range from 3298 Ma to 78 Ma,and show six major age populations:2476-2344 Ma,2016-1831 Ma,1296-759 Ma,455-406 Ma,262-210 Ma,and 187-78 Ma.The youngest age of these detrital zircons is 78 Ma,indicating that the maximum depositional age of the sandstones is Campanian.Permian-Late Cretaceous detrital zircons are interpreted as having been derived from the nearby Schwaner Mountains and the Permian-Triassic tin belt granitoids in Southeast Asia(SE Asia).Archean-Carboniferous detrital zircons have a continental Gondwana provenance,with their age spectra similar to those of northwestern Australia,indicating that these zircons could be derived from the orogenic belts and cratons in northwestern and central Australia.The provenance of these detrital zircons in this study indicates the SW Borneo block was located on the northwestern margin of Australia during the Paleozoic,in the region of the Banda Embayment.SW Borneo rifted from Australia and moved northward in the Early Jurassic,and this block was added to Sundaland in the Early Cretaceous.The Luconia-Dangerous Grounds continental fragment derived from East Asia collided with SW Borneo after subduction in the Cretaceous,which induced the widespread magmatism in the Schwaner Mountains in SW Borneo.
文摘Uranium exploration especially in currently non-producing countries like Nigeria possesses high economic prospect. This study investigates a new uranium prospect in Mika, Northeastern Nigeria. The Mika uranium mineralization is located in Mika, Taraba State. Two lodes were identified and additional nine (9) trenches were added. The main lode in the west extends about 10 m, ore vein strikes 348°, inclination 42°and the strike of the lode 306°with average uranium content of 18%. The eastern trench is about 8 × 4 × 6 m which exposes a veinlet of pitchblende. From the petrography, one can deduce that the granitic host rock has suffered deformation resulting in crushing of quartz crystals and stretching of plagioclase. The uraninite and chalcedony in the late phase filled up the fractures along the crystal grain boundaries as veinlets. The laboratory gamma ray analysis of the samples showed that the secondary uranium content is 0.1%, while the primary uranium ore grade is 1.5%. Radiometric in situ measurements showed that Th and K ranges from 47.3 - 3654 ppm and 4.26% - 6.26% respectively. From the survey, a strong radiometric zone extends 800 × 35 m in an NW-SE direction and has highest radiation content of 1200 cpm against the background count rate of 30 cpm. Generally, the uranium concentrations in the ores in Mika area range from 0.03% - 0.12%. Since only the surface occurrences have been explored, the study area is a good prospect for future development when properly explored. The North-eastern Nigeria has been roughly explored by Nigeria Uranium Mining Company (NUMCO) in 1980, but no formal exploration had been followed after that, especially near the site of this article. The company (ACE Mines, Ltd) of the first author was among the few uranium mining companies approved in the list of Nigerian Geological Survey agency of Abuja in Nigeria. The authors determined the coordinates of the site in their first survey which formed the prospect area in the licence.
基金supported by Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring, Ministry of Education, Central South University (No. 2018YSJS01)the National Natural Science Foundation of China (No. 41673040)+1 种基金the DREAM project of MOST China (No. 2016YFC0600404)QingzhenYunfeng Aluminum and Iron Mining Co. (No. 738010033)
文摘The Boloven bauxite deposit occurs either in the weathered basalt(alkali basalt and tholeiite), or in the Cretaceous sandstone. It is generally agreed that the bauxite deposits/laterites overlying the alkali basalt and tholeiite were derived from weathering of underlying basalt, however, the origin of bauxite deposit overlying the sandstone remains controversial. Chondrite-normalized REE patterns show that the bauxite ores/laterites overlying the sandstone exhibit quite similar chondrite-normalized REE patterns to those overlying the alkali basalt. Diagram of Al-Ti-Zr shows that the bauxite ores/laterites overlying the sandstone, tholeiite and alkali basalt are close to each other and to the calc-alkaline suite, however, significantly different from the sandstone and shales. Binary diagram of log Nb/Y vs log Zr/Ti further indicates that the parent rocks of bauxite ores/laterites overlying the sandstone belong to the suit of ultra-alkali to alkali basalt. Multivariate statistical analysis of geochemical data exhibit that the geochemical characteristics of HREE, Y, LREE and Al_2O_3 for bauxite ores/laterites overlying the sandstone are similar to those overlying the alkali basalt(15.7 Ma), obviously different from those overlying the tholeiite(1.2 to 0.5 Ma). Consequently, it can be inferred that the bauxite deposits/laterites overlying the sandstone were derived from the alkali basalt.
基金supported by the National Natural Science Foundation of China(52200130,22308100).
文摘This study delves into the intricate deposition dynamics of submicron particles within electric-flow coupled fields,underscoring the unique challenges posed by their minuscule size,aggregation tendencies,and biological reactivity.Employing an operando investigation system that synergizes microfluidic technology with advanced micro-visualization techniques within a lab-on-a-chip framework enables a meticulous examination of the dynamic deposition phenomena.The incorporation of object detection and deep learning methodologies in image processing streamlines the automatic identification and swift extraction of crucial data,effectively tackling the complexities associated with capturing and mitigating these hazardous particles.Combined with the analysis of the growth behavior of particle chain under different applied voltages,it established that a linear relationship exists between the applied voltage and θ.And there is a negative correlation between the average particle chain length and electric field strength at the collection electrode surface(4.2×10^(5)to 1.6×10^(6)V·m^(-1)).The morphology of the deposited particle agglomerate at different electric field strengths is proposed:dendritic agglomerate,long chain agglomerate,and short chain agglomerate.
基金supported by the National Foundation of High Technology of China(2006AA020701 and 2006AA020803)National Program on Key Basic Research Projects 973 of China(2006CB705700)+1 种基金the Nature Science Foundation of Zhejiang Province(2006C21G3210005)Tsinghua-Yuyuan Medicine Foundation(40000510B).
文摘Loop-mediated isothermal amplification(LAMP)is a novel nucleic acid amplification method.Compared with the widely utilized polymerase chain reaction(PCR),LAMP has higher speed and efficiency as well as lower requirement for system temperature control because the whole amplification process is isothermal and no efforts are needed to switch between different temperatures.In this paper,we designed and fabricated different kinds of polycarbonate(PC)microfluid chips,explored appropriate reaction condition for LAMP in microenvironment(1 nL→10μL),and developed a microfluidic isothermal amplification detection system.The DNA optimal amplification temperature is obtained;the starting time of exponential amplification of DNA is put forward farther.The optimal condition of DNA amplification in microenvironment,with a little reaction materials and early starting exponential amplification time of DNA are very important for clinic DNA detection and the application of Lab-on-a-Chip.
基金Supported by the National Foundation of High Technology of China(2006AA020701 and 2006AA020803)National Program on Key Basic Research Projects 973 of China(2006CB705700)+1 种基金the Nature Science Foundation of Zhejiang Province(2006C21G3210005)Tsinghua-Yuyuan Medicine Foundation(40000510B).
文摘A surface plasmon resonance imaging(SPRI)system was developed for the discrimination of proteins on a gold surface.As a label-free and high-throughput technique,SPRI enables simultaneously monitoring of the biomolecular interactions at low concentrations.We used SPRI as a label-free and parallel method to detect different proteins based on protein microarray.Bovine Serum Albumin(BSA),Casein and Immunoglobulin G(IgG)were immobilized onto the Au surface of a gold-coated glass chip as spots forming a 6×6 matrix.These proteins can be discriminated directly by changing the incident angle of light.Excellent reproducibility for label-free detection of protein molecules was achieved.This SPRI platform represents a simple and robust method for performing high-sensitivity detection of protein microarray.
基金National Natural Science Foundation of China(12374296,62401474)Key Research and Development Program of Shaanxi Province(2023-YBGY-247,2024GXZDCYL-01-31)+1 种基金Basic and Applied Basic Research Foundation of Guangdong Province(2024A1515011725)Innovation Foundation for Doctor Dissertation of Northwestern Polytechnical University(CX2024029)。
文摘Symmetry plays a fundamental role in topological photonic crystals, and topological phase transitions induced bydisorder have also been extensively explored in recent years. However, in this work, we find anisotropy can beinduced by reducing symmetry in a C_(2v) symmetry triangular photonic crystal. We investigate that anisotropyinducedinterfaces profoundly affect edge states and enable the realization of slow light dispersion. Numericalsimulations reveal a transition from gapless chiral edge modes to gapped flat band dispersion. Furthermore, weobserve higher-order corner states in corner structures constructed by anisotropic interfaces. The corner states canbe induced and localized at different lattice positions, thereby realizing multiple types of higher-order topologicalstates. We demonstrate the significance of anisotropic geometry in topological photonics. These findings opennew possibilities for steering wave transport in multiple dimensions and offer, to our knowledge, a novel researchperspective on the transformation of topological states induced by anisotropic lattices.
基金supported by the Science and Technique Project of Yantai University(HJ19B92:1115/2219014)the Natural Science Foundation of Shandong Province(ZR2024ME069+2 种基金ZR202209150060)the Beijing Scholars Training Program Grants(BJXZ-2024-02)the Natural Science Foundation of Fujian Province(2022J01984).
文摘The identification of complete ammonia oxidizers(comammox)within the nitriteoxidizing bacteria(NOB)genus Nitrospira,capable of oxidizing ammonia directly to nitrite and nitrate,represents a pivotal advancement in elucidating the microbial and metabolic pathways underlying nitrification in the global nitrogen cycle.Although comammox Nitrospira have been consistently identified across diverse environmental habitats,their rapid enrichment from complex activated sludge systems remains challenging owing to their intrinsically low growth rates and the restricted availability of cultured isolates.In this study,Candidatus Nitrospira inopinata(Ca.N.inopinata)was successfully enriched from anammox-inoculated sludge within 70 d under low ammonia concentrations(~4.88 mg/L),ambient temperatures(21.6-28.4℃),and minimal aeration(0-0.01 mg/L),facilitated by the application of kanamycin(KAN).By employing 16S rRNA gene amplicon sequencing and quantitative polymerase chain reaction(qPCR)targeting the functional marker gene amoA,Ca.N.inopinata was identified as the dominant ammonia oxidizer,achieving a relative abundance of 95.22% in the nitrifying community.Kanamycin was shown to exert significant selective pressure,further enhancing the enrichment of Ca.N.inopinata.These findings demonstrate the feasibility of establishing comammox Nitrospira through direct inoculation of anammox pellets coupled with kanamycin,offering a robust and efficient strategy for rapid enrichment of comammox Nitrospira for biotechnological applications,while underscoring the energy-efficient advantages of comammox-driven ammonia oxidation processes.