New Recognized Intellect for Prospecting Large-superlarge Mineral Deposits

Based on the data base of 1285 mineral deposits of 22 commodities in 121 countries of 6 continents of the world, the authors use the linear trend analysis for their reserves to determine the cut-off limited order of reserves to select 36 exceptional superlarge （as peak mineral）, 95 superlarge and 314 large deposits as new recognized intellect for their quantitative change. We have projected above 445 large-superlarge deposits on （1：5 M） global tectonic background map and divided 4 metallogenic domains, 21 metallogenic belts. Global metallogeny of large-superlarge deposits are： unity by endogenic, exogenic metamorphic and epigenetic in origin; speciality in different metallogenic domains and belts; preferentiality to ore-forming elements of Cu, Au, Fe, Ag, Cr, Mn, Zn, Pb, Sb, Hg, to continental margins or plate convergent belts, to Intra-continental tectono-magmatic complex belts and Large ductile shear zones; abnormality by the global oxyatmversion （excess oxygen atmospheric event） in Archean, redoxyatmversion （lack oxygen atmospheric event） in Proterozoic-Paleozoic, and tectonosphere thermal erosion （great amount of tectonic magmatic event） in Mesozoic-Cenozoic.

The Major Ore Clusters of Super-Large Iron Deposits in the World, Present Situation of Iron Resources in China, and Prospect

The metamorphosed sedimentary type of iron deposits（BIF） is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces（belts）, such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type（BIF）, magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type（BIF） as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets.

Quantitative Prediction of Concentrated Regions of Large and Superlarge Deposits in China

Identification and quantitative prediction of large and superlarge mineral deposits of solid mineral resources using the mineral resource prediction theory and method with comprehensive information is carried out nationwide in China at a scale of 1∶5 000 000. Using deposit concentrated regions as the model units and concentrated mineralization anomaly regions as prediction units, the prediction is performed on GIS platform. The technical route and research method of locating large and superlarge mineral deposits and principle of compiling attribute table of independent variables and functional variables are proposed. Upon methodology study, the qualitative locating and quantitative predicting mineral deposits are carried out with quantitative theory Ⅲ and characteristic analysis, respectively, and the advantage and disadvantage of two methods are discussed. This research is significant for mineral resource prediction in ten provinces of western China.

Metallogenic mechanisms of super-large Cu and Au deposits in the Dexing region and simulating experiments

Based on the results of previous studies and under the direction of the theory of "ore deposit genesis",the authors made use of high temperature and high pressure experimental facilities and conditions at the Tectono-geochemistry Research Room under the State Key Laboratory of Ore Deposit Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,and put the focus on the multi-source of tectonically controlling ore-forming materials,the characteristics of multi-stage and multi-episode hydrothermal activities and mineralization and the characteristics of multi-genesis and multi-ore deposition so as to shed light on the metallogenic mechanisms of super-large Cu and Au deposits.In addition simulating experiments were made on multi-stage and multi-episode tectonic activities and rock and ore deformation,multi-stage and multi-episode tectonic activities and mobilization and migration of ore-forming materials,and multi-stage and multi-episode tectonic activities and superimposition and enrichment of ore-forming materials.The experimental results showed that under the action of multi-stage and multi-episode tectonic stress the deformation and fragmentation of not only rocks and ores have been intensified,and but also the ore-forming materials originally disbursed in the rocks and ores have been mobilized and migrated and superimposed and enriched.The experimental results also provided the scientific experimental data and grounds for deep-going research on the rules of metallogenesis and geneses of super-large ore deposits in the Dexing region,Jiangxi Province.

A Super-Large Rb-Nb Rare Metal Deposit has been Discovered in Huashi Village of Xinglong County, Hebei Province

Objective The Huashi Village in Xinglong County of Hebei Province is located in the Yanshan subsidence zone in the central eastern North China Plate, which is 137 km away from Beijing City （Fig. la）. This area has undergone large -scale magmatic intrusion affected by the tectonic compression of the Pacific Plate in the Mesozoic （known as the Yanshanian movement） to form many alkaline rocks such as the Wulingshan rock mass. Previous studies have conducted petrological research and reconnaissance survey of rare metal ores in this area （Tian Shuzhang and Guo Zongshan, 1981; Xu Baoling et al., 1996）. In 2016, the Qinhuangdao Mineral and Hydrology Engineering Geological Brigade of Hebei Bureau of Geology and Mineral Resources Exploration implemented the project of Reconnaissance of Rare Metal Ores Including Rubidium in Huashi Village of Xinglong County, Hebei Province, and discovered super-large rare metal deposits of rubidium and biobium in the Madi alkali feldspar granite bodies in the Huashi Village to achieve great breakthrough of rare metal ore prospecting.

New Zircon U-Pb Age of the Super-Large Lijiagou Spodumene Deposit in Songpan Garze Fold Belt, Eastern Tibet： Implications for Early Jurassic Rare-Metal Polymetallic Event

Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the SGFB,including the Xuebaoding,Jiajika,Keeryin rare metal deposits and Danba muscovite deposit(Li Jiankang et al.,2015).The newly discovered super-large Lijiagou

New Re-Os Dating of Auriferous Pyrite from the Suoluogou Large Gold Deposit in Muli County, West Sichuan Province

Objective The Suoluogou gold depositin Muli County of Sichuan Province is located in the southern section of the GanziLitang suture zone(Fig.la),which is the largest gold deposit discovered in this suture zone in recent years.At present,the exploration of the Suoluogou gold deposit is still in progress,and the amount of resource is increasing.

One potential superlarge Pb-Zn ore occurrence with Himalayan thermal brine genesis——Wuqia Region, Xinjiang, China

The paper focuses on geological and geochemical evidence of thermal brine genesis of Pb Zn deposits in Wuqia district, Xinjiang. The results suggest that the known Pb Zn deposits, such as Wulagen, are thermal brine genesis, which is supported by the features of tectonic setting, magma and regional metamorphism, and the characteristics of trace element distribution in strata and redistribution in the ore forming process, the REE patterns and their main parameters of main type ores, the composition features and the source indicators of Pb, S isotopes. Ore forming conditions of superlarge Pb Zn deposits studies show that there exists tectonic and sources setting of Jinding type superlarge Pb Zn deposits in this area. Five Pb Zn ore belts and central uplift belts discovered lately have not only confirmed that the genesis of Wulagen Pb Zn deposits is thermal genesis, but also further proved that there exists tectonic and source setting of Jinding type superlarge Pb Zn deposit in the study area. Mineral deposit model was described and prospecting potentiality of superlarge Pb Zn deposit and their significance were discussed.

A Novel Soft Start Method of Super Large Capacity High Voltage Motor

The large current generated by starting directly of super large capacity and high voltage induction motor would have a huge impact on the grid as well as the motor itself.The variation of the power factor and electromagnetic torque during direct start of motors with different capacity and voltage levels are obtained.Aiming at the problem that the secondary impact of auto-transformer starter is too large and the cost of magnetic control starter is too high,the auto-transformer and magnetic control soft start method of super large capacity and high voltage motor is proposed and the basic working principle is analyzed.The calculation formula of cost for magnetic control soft starter and auto-transformer and magnetic control soft starter is deduced,and specific examples are analyzed and compared.It is concluded that the choice of auto-transformer with appropriate tapping ratio can greatly reduce the cost of auto-transformer and magnetic control soft starter compared with the other one.Finally,the simulation and experiment results show that the start method can effectively avoid secondary current impact and constrain the motor starting current to less than 2.5 times the rated current.

Numerical analysis of ice accretion effects at super-cooled large droplet conditions on airfoil aerodynamics

Changes in flow field around NACA23012 airfoil from a clean condition to a super-cooled large droplet （SLD） condition were simulated, and variations in aerodynamic parameters were calculated using FLUENT. In the case of numerical simulation for a clean airfoil, flow field characteristics simulated agreed well with theory analysis, indicating that turbulence models and parameters setting are feasible. Aerodynamic parameters for iced airfoil were calculated using the same method and agreed with those measured test data under the same environment in icing wind tunnels by S. Lee. Conclusion is made that the numerical simulation is valid, and it can be an alternative to study ice accretion effects at the SLD condition on airfoil aerodynamics, leading to reduction in research cycle time and cost.

Low-Temperature Soft-Cover-Assisted Hydrolysis Deposition of Large-Scale TiO_2 Layer for Efficient Perovskite Solar Modules

Perovskite solar cells with TiO_2 electron transport layers exhibit power conversion efficiency(PCE) as high as 22.7% in single cells. However, the preparation process of the TiO_2 layer is adopted by an unscalable method or requires high-temperature sintering, which precludes its potential use for mass production of flexible devices. In this study, a scalable low-temperature softcover-assisted hydrolysis(SAH) method is presented,where the precursor solution is sandwiched between a soft cover and preheated substrate to form a closed hydrolysis environment. Compact homogeneous TiO_2 films with a needle-like structure were obtained after the hydrolysis of a TiCl_4 aqueous solution. Moreover, by careful optimization of the TiO_2 fabrication conditions, a high PCE of 14.01% could be achieved for a solar module(4 × 4 cm^2) prepared using the SAH method. This method provides a novel approach for the efficient scale-up of the low-temperature TiO_2 film growth for industrial applications.

Spray deposition for making large size billet with swing atomizer

The movement mode of the atomizer is a very important parameter during spray deposition process,which has direct influence on the size and surface texture of the billets. To resolve the problem of manufacturing large size billets,a method of spray deposition by the atomizer with off-center swing was put forward. The atomizer was driven by the alternating current servomotor to swing within 7° at varying speed. The influence of the atomizer parameters,such as translation of the atomizer,swing angle of the atomizer,substrate falling speed and spraying pressure,on the spray deposition was studied. The optimized parameters of the spray deposition process were obtained. The results show that the large size billets with uniform surface quality can be made through adjusting swing frequency and angle of the atomizer,offset distance of the atomizer and inclined angle of the substrate; the valid spray area will decrease and the dimension of top surface will reduce when pressure is less than 0.4 MPa within certain spray distance; meantime,the moving time and cooling time of the droplets are extended,which will lead to loose structure and bad densification. When the pressure,the swing angle and the eccentric offset of the atomization equal 0.5 MPa,7° and 60 mm,respectively,large size billets with fine texture and diameter of 500 mm can be produced.

Geological Features,Mineralization Types and Metallogenic Setting of the Phlaythong Large Iron Deposit,Southern Laos

The Phlaythong large iron deposit in Shampasak of southern Laos,is located in the Kon Tum microblock （Fig.1A）,central-southern part of the Indo-China block,and the geographic coordinate of the central mining area is 14°43′04″ N and 106°07′02″ E.

The Metallogenetic Processes and Environment of a Large Ag-V Deposit in Black Rock Series

Located in Western Hubei Province,this deposit is a large-scale Ag-V ore deposit,listed among the fifth type of silver deposit in China.1 Geological Characteristics It lies in the NE sector of the Yangtze flat of the Yangtze paraplatform.There are sporadically magmatic rocks and fold basement made up of upper Archaeozoicmiddle and lower Proterozoic strata.The sedimentary cover consists of Sinian-lower Paleozoic marine sediments,Mesozoic-Cenozoic intercalated marine and nonmarine sediments or nonmarine sediments.

The Emeishan large igneous province:A synthesis

The late Permian Emeishan large igneous province （EL1P） covers -0.3× 10-6 kmL of the western margin of the Yangtze Block and Tibetan Plateau with displaced, correlative units in northern Vietnam （Song Da zone）. The ELIP is of particular interest because it contains numerous world-class base metal deposits and is contemporaneous with the late Capitanian （-260 Ma） mass extinction. The flood basalts are the signature feature of the ELIP but there are also ultramafic and silicic volcanic rocks and layered mafic- ultramafic and silicic plutonic rocks exposed. The EL1P is divided into three nearly concentric zones （i.e. inner, middle and outer） which correspond to progressively thicker crust from the inner to the outer zone. The eruptive age of the ELIP is constrained by geological, paleomagnetic and geochronological evidence to an interval of 〈3 Ma. The presence of picritic rocks and thick piles of flood basalts testifies to high temperature thermal regime however there is uncertainty as to whether these magmas were derived from the subcontinental lithospheric mantle or sub-lithospheric mantle （i.e. asthenosphere or mantle plume） sources or both. The range of Sr （Isr ≈ 0.7040-0.7132）, Nd （ENd（t） ≈ -14 tO ＋8）, Pb （206-pb/204-pb1 ≈ 17.9-20.6） and Os （Yos ≈ -5 to ＋11） isotope values of the ultramafic and mafic rocks does not permit a conclusive answer to ultimate source origin of the primitive rocks but it is clear that some rocks were affected by crustal contamination and the presence of near-depleted isotope compo- sitions suggests that there is a sub-lithospheric mantle component in the system. The silicic rocks are derived by basaltic magmas/rocks through fractional crystallization or partial melting, crustal melting or by interactions between mafic and crustal melts. The formation of the Fe-Ti-V oxide-ore deposits is probably due to a combination of fractional crystallization of Ti-rich basalt and fluxing of C02-rich fluids whereas the Ni-Cu-（PGE） deposits are related to crystallization and crustal contamination of mafic or ultramafic magmas with subsequent segregation of a sulphide-rich portion. The ELIP is considered to be a mantle plume-derived LIP however the primary evidence for such a model is less convincing （e.g. uplift and geochemistry） and is far more complicated than previously suggested but is likely to be derived from a relatively short-lived, plume-like upwelling of mantle-derived magmas. The emplacement of the ELIP may have adversely affected the short-term environmental conditions and contributed to the decline in biota durin~ the late Caoitanian.

Contrasting oxidation states of low-Ti and high-Ti magmas control Ni-Cu sulfide and Fe-Ti oxide mineralization in Emeishan Large Igneous Province

Magmatic Ni-Cu-(PGE) sulfide and Fe-Ti oxide deposits in plume-related large igneous provinces(LIPs)are commonly related to low-Ti and high-Ti series magmas, respectively, but the major factors that control such a relationship of metallogenic types and magma compositions are unclear. Magma fOcontrols sulfur status and relative timing of Fe-Ti oxide saturation in mafic magmas, which may help clarify this issue. Taking the Emeishan LIP as a case, we calculated the magma fOof the high-Ti and low-Ti picrites based on the olivine-spinel oxygen barometer, and the partitioning of V in olivine. The obtained fOof the high-Ti series magma(FMQ + 1.1 to FMQ + 2.6) is higher than that of the low-Ti series magma(FMQ-0.5to FMQ + 0.5). The magma fOof the high-Ti and low-Ti picrites containing Fo > 90 olivine reveals that the mantle source of the high-Ti series is likely more oxidized than that of the low-Ti series. The results using the ’lambda REE’ approach show that the high-Ti series may have been derived from relatively oxidized mantle with garnet pyroxenite component. The S contents at sulfide saturation(SCSS) of the two series magmas were calculated based on liquid compositions obtained from the alpha Melts modeling, and the results show that the low-Ti series magma could easily attain the sulfide saturation as it has low fOwith S being dominantly as S. In contrast, the oxidized high-Ti series magma is difficult to attain the sulfide saturation, but could crystallize Fe-Ti oxides at magma MgO content of ~7.0 wt.%. Thus, contrasting magma fOof low-Ti and high-Ti series in plume-related LIPs may play an important role in producing two different styles of metallogeny.

Synthesis of a Large Diamond Crystal with a Smooth(100) Facet at its Top Through MPCVD

A large diamond crystal up to 500 μm in diameter with a smooth （100） facet at its top has been synthesized on Mo substrate through microwave plasma chemical vapor deposition （MPCVD）. Its morphology and quality were characterized by scanning electron microscopy （SEM）, and the growth mechanism was roughly illustrated from both macroscopic and microscopic viewpoints. It was found that morphological instabilities are a major factor resulting in synthesis of large diamond crystals, moreover, high microwave power density （MPD）, high CH4 concentrations, high pressure, high substrate surface temperature and the addition of a small amount of O2 were also necessary for the synthesis of large diamond crystals.

Intelligent optimization of the structure of the large section highway tunnel based on improved immune genetic algorithm

As in the building of deep buried long tunnels,there are complicated conditions such as great deformation,high stress,multi-variables,high non-linearity and so on,the algorithm for structure optimization and its application in tunnel engineering are still in the starting stage. Along with the rapid development of highways across the country,it has become a very urgent task to be tackled to carry out the optimization design of the structure of the section of the tunnel to lessen excavation workload and to reinforce the support. Artificial intelligence demonstrates an extremely strong capability of identifying,expressing and disposing such kind of multiple variables and complicated non-linear relations. In this paper,a comprehensive consideration of the strategy of the selection and updating of the concentration and adaptability of the immune algorithm is made to replace the selection mode in the original genetic algorithm which depends simply on the adaptability value. Such an algorithm has the advantages of both the immune algorithm and the genetic algorithm,thus serving the purpose of not only enhancing the individual adaptability but maintaining the individual diversity as well. By use of the identifying function of the antigen memory,the global search capability of the immune genetic algorithm is raised,thereby avoiding the occurrence of the premature phenomenon. By optimizing the structure of the section of the Huayuan tunnel,the current excavation area and support design are adjusted. A conclusion with applicable value is arrived at. At a higher computational speed and a higher efficiency,the current method is verified to have advantages in the optimization computation of the tunnel project. This also suggests that the application of the immune genetic algorithm has a practical significance to the stability assessment and informationization design of the wall rock of the tunnel.

Preparation of Large-Scale Double-Side BDD Electrodes and Their Electrochemical Performances

Boron doped diamond(BDD)performs well in electrochemical oxidation for organic pollutants thanks to its wide electrochemical window and superior chemical stability.We presented a method to obtain well-adherent large-scale BDD/Nb electrode by the modified hot filament chemical vapor deposition system(HFCVD).SiC particles were sand blasted to enhance the adhesion of BDD coating.The BDD coating was then deposited on both sides of Nb which was placed vertically and closely with filament grids on both sides.The BDD/Nb electrodes had no deformation because the thermal deformations of the BDD films on both sides of the Nb substrate conteracted each other during cooling process after deposition.The surface morphology and purity of the BDD/Nb electrode were analyzed by Raman and scanning elestron microscope(SEM)techniques.Scratch test was used to investigate the adhesion of BDD films.The electrochemical performances were measured by cyclic voltammetry test.The BDD electrode at the B/C ratio of 2 000×10^(-6) held a higher oxygen evolution potential thanks to its high sp3 carbon content.Accelerated life test illustrated that the sandblasting pretreatment obviously enhanced the adhesion of BDD coating which resulted in a longer service duration than the un-sandblasted one.