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The Daheishan supergiant porphyry molybdenum deposit (also referred to as the Daheishan deposit) is the second largest molybdenum deposit in Asia and ranks fifth among the top seven molybdenum deposits globally with total molybdenum reserves of 1.65 billion tons, an average molybdenum ore grade of 0.081%, and molybdenum resources of 1.09 million tons. The main ore body is housed in the granodiorite porphyry plutons and their surrounding inequigranular granodiorite plutons, with high-grade ores largely located in the ore-bearing granodiorite porphyries in the middle-upper part of the porphyry plutons. Specifically, it appears as an ore pipe with a large upper part and a small lower part, measuring about 1700 m in length and width, extending for about 500 m vertically, and covering an area of 2.3 km2. Mineralogically, the main ore body consists of molybdenite, chalcopyrite, and sphalerite horizontally from its center outward and exhibits molybdenite, azurite, and pyrite vertically from top to bottom. The primary ore minerals include pyrite and molybdenite, and the secondary ore minerals include sphalerite, chalcopyrite, tetrahedrite, and scheelite, with average grades of molybdenum, copper, sulfur, gallium, and rhenium being 0.081%, 0.033%, 1.67%, 0.001%, and 0.0012%, respectively. The ore-forming fluids of the Daheishan deposit originated as the CO2-H2O-NaCl multiphase magmatic fluid system, rich in CO2and bearing minor amounts of CH4, N2, and H2S, and later mixed with meteoric precipitation. In various mineralization stages, the ore-forming fluids had homogenization temperatures of > 420°C–400°C, 360°C–350°C, 340°C–230°C, 220°C–210°C, and 180°C–160°C and salinities of > 41.05%–9.8% NaCleqv, 38.16%–4.48% NaCleqv, 35.78%–4.49% NaCleqv, 7.43% NaCleqv, and 7.8%–9.5% NaCleqv, respectively. The mineralization of the Daheishan deposit occurred at 186–167 Ma. The granites closely related to the mineralization include granodiorites (granodiorite porphyries) and monzogranites (monzogranite porphyries), which were mineralized after magmatic evolution (189–167 Ma). Moreover, these mineralization-related granites exhibit low initial strontium content and high initial neodymium content, indicating that these granites underwent crust-mantle mixing. The Daheishan deposit formed during the Early-Middle Jurassic, during which basaltic magma underplating induced the lower-crust melting, leading to the formation of magma chambers. After the fractional crystallization of magmas, ore-bearing fluids formed. As the temperature and pressure decreased, the ore-bearing fluids boiled drops while ascending, leading to massive unloading of metal elements. Consequently, brecciated and veinlet-disseminated ore bodies formed.

The reserves of the Duobaoshan porphyry Cu-Au-Mo-Ag deposit (also referred to as the Duobaoshan porphyry Cu deposit) ranks first among the copper deposits in China and 33rdamong the porphyry copper deposits in the world. It has proven resources of copper (Cu), molybdenum (Mo), gold (Au), and silver (Ag) of 2.28×106t, 80×103t, 73 t, and 1046 t, respectively. The major characteristics of the Duobaoshan porphyry Cu deposit are as follows. It is located in a zone sandwiched by the Siberian, North China, and paleo-Pacific plates in an island arc tectonic setting and was formed by the Paleozoic mineralization and the Mesozoic mineralization induced by superposition and transformation. The metallogenic porphyries are the Middle Hercynian granodiorite porphyries. The alterations of surrounding rocks are distributed in a ring form. With silicified porphyries at the center, the alteration zones of K-feldspar, biotite, sericite, and propylite occur from inside to outside. This deposit is composed of 215 ore bodies (including 14 major ore bodies) in four mineralized zones. Ore body No. X in the No. 3 mineralized zone has the largest resource reserves, accounting for more than 78% of the total reserves of the deposit. Major ore components include Cu, Mo, Au, Ag, Se, and Ga, which have an average content of 0.46%, 0.015%, 0.16 g/t, 1.22 g/t, 0.0003%, and 0.001%–0.003%, respectively. The ore minerals of this deposit primarily include pyrite, chalcopyrite, bornite, and molybdenite, followed by magnetite, hematite, rutile, gelenite, and sphalerite. The ore-forming fluids of this deposit were magmatic water in the early metallogenic stage and then the mixture of meteoric water and magmatic water at the late metallogenic stage. The ore-forming fluids experienced three stages. The ore-forming fluids of stage I had a hydrochemical type of H2O-CO2-NaCl, an ore-forming temperature of 375–650°C, and ore-forming pressure of 110–160 MPa. The ore-forming fluids of stage II had a hydrochemical type of H2O-CO2-NaCl, an ore-forming temperature of 310–350°C, and ore-forming pressure of 58–80 MPa. The ore-forming fluids of stage III had a hydrochemical type of NaCl-H2O, an ore-forming temperature of 210–290°C, and ore-forming pressure of 5–12 MPa. The Cu-Au-Mo-Ag mineralization mainly occurred at stages I and II, with the ore-forming materials having a mixed crust-mantle source. The Duobaoshan porphyry Cu deposit was formed in the initial subduction environment of the Paleo-Asian Ocean Plate during the Early Ordovician. Then, due to the closure of the Mongol-Okhotsk Ocean and the subduction and compression of the Paleo-Pacific Ocean, a composite orogenic metallogenic model of the deposit was formed. In other words, it is a porphyry - epithermal copper-gold polymetallic mineralization system of composite orogeny consisting of Paleozoic island arcs and Mesozoic orogeny and extension.

Porous titanium oxide (TiO2) nanocubes combining with carbon nanotubes (CNTs) framework greatly improve the utilization efficiency and enhance their sodium storage.

Through the introduction of the condensate system in 350 MW supercritical unit,we analysis and study the whole control strategy of condensate water based on automatic startup and shutdown control system.We realize condensate system of automatic startup and shutdown control and can automatically adjust deaerator level and pressure of condensation water pipe. The results is that the whole control strategy of condensate water based on automatic startup and shutdown control system is very good in controlling quality and has a good application value. 0 Preface APS is a control center of startup and shutdown automatically according to the set procedures ,which is to control each equipment/system cooperated with Data Acquisition System (DAS), Boiler Turbine Sequence Control System (SCS), Modulating control system (MCS) and Furnace Safeguard Supervisory System (FSSS), steam turbine digital electro-hydraulic control system (DEH), Coordinated Control system (CCS), Electric Control System (ECS), Automatic Voltage Regulation system (AVR) and so on. [1]

n this paper, the main performances of the lead-acid battery used on in a real off-road vehicle were tested through experiments. The lead-acid battery voltage and current characteristic curves of the self-discharge, real vehicle starting experiment and battery electricity demand experiment performance in the different conditions were studied. The results show that this lead-acid battery can be used as the preferred battery and the charging and discharging rules of this battery can be used to improve the vehicle design.

In order to increase the validation of preventive maintenance modes decision generally gotten by analyst’s subjective and qualitative judgment in reliability-centered maintenance analysis (RCMA), a projection model of intuitionistic fuzzy multiple attribution decision making for preventive maintenance modes in RCMA was presented. An illustration was used to validate the model of decision making about preventive maintenance modes in RCMA for vehicle equipment. The results indicate that the model is suitable to select the optimum preventive maintenance mode. Compared with the fuzzy comprehensive model that describes fuzzy information only by degree of membership, the intuitionistic fuzzy model more precisely and entirely describes fuzzy information come from RCMA by degree of membership, non-membership and hesitation. Then it is more adequate in group decision making for RCMA. It may be used in developing decision support system for RCMA.

Creep damage is an important failure factor of high-temperature alloy. The fatigue crack growth under elevated temperature of the material is investigated for life prediction. In this paper, the numerical simulation of the crack propagation in nickel-based super alloy, IN718, was presented. A modified creep damage model was employed to accumulate the creep damage under cyclic loading conditions. The numerical results exhibit a reasonable agreement in the comparison with the experimental data. The cohesive zone approach, combining with the extended finite element method, has the ability to simulate the creep-fatigue crack propagation even for more complex loading conditions and specimen geometries.

Extended finite element method is widely used to simulate the discontinuity problems, e.g. fatigue crack growth. This paper mainly analyzes the fatigue crack propagation under elevated temperature in nickel-based super alloy with extended finite element method. Cohesive zone model is used to describe the mechanical behavior around the crack tip. A modified creep damage model is introduced. Fatigue damage and creep damage are accumulated in a linear relationship. And the results produced by computational code are presented and draw a comparison with experimental observation.

In this paper，PANI/SSA thin films were deposited by MAPLE technique with different lasers. The structures and composition of films were characterized by XPS. The XPS results showed that because of the protection of matrix, the main structures and composition of films were protected effectively during deposition. While different lasers bring different influence to film structures. To short-wave laser, photochemical effect is obvious, the structures related to doping showed obvious change. To long-wave laser, photochemical effect did not bring obvious change to related structures, the XPS peaks showed no difference to that of PANI/SSA powder.

To establish the model of hospitalization cost in patients with cerebral infarction based on neural network using artificial network mathematical model, and setting the appropriate parameters. LM, BR, OSS, SCG four algorithms were used respectively to model 3, 5,10,15, 20 neuron number in different hidden layers and comparisons between model fitting ability and its generalization ability were made. The model which involves a hidden layer, 8 input neurons, 15 neurons in output layer network is the optimal model by using OSS system.

Three novel hyperbranched polycarbosilazanes were synthesized via hydrosilylation reaction and characterized by FT-IR, 1H NMR, 13C NMR, 29Si NMR, and laser light scattering. First, one AB4 type monomer bis(N,N‐diallylamino)‐methylsilane (M1) and two AB2 type monomers (N,N‐diallylamino)‐dimethylsilane (M2) and N,N‐bis (dimethylsilyl)‐allylamine (M3) were prepared by aminolysis of MeHSiCl2 and Me2HSiCl with diallylamine and allylamine. Then monomers were polymerized into hyperbranched polycarbosilazanes via hydrosilylation reaction using H2PtCl6 as the catalyst. The measurements indicate that α‐hydrosilylation mainly occurs during the polymerization and the polymers synthesized consist of &tbond;Si&bond;N&bond;C&tbond; linkages with hyperbranched architectures carrying a large amount of functional vinyl or &tbond;Si&bond;H end groups. The molecular weights ($\overline M _{\rm w} $) of the three polymers were found to be 13 500, 4 600, and 3 900 g · mol−1, respectively.

A hyperbranched polyethoxysiloxane was synthesized via hydrolytic polycondensation between methyltriethoxysilane (MTES) and tetraethoxysilane (TEOS), with hydrochloride acid as catalyst. FTIR, 1H NMR, 29Si NMR, and GPC measurements confirmed that the polyethoxysiloxane synthesized was indeed a hyperbranched polymer with a degree of branching of 0.67. It was also found that there were no silanol groups in polymer matrix. This quality can effectively enhance its storage stability. Based on the hyperbranched polyethoxysiloxane, a novel antifouling coating with high curing speed at ambient temperature was developed. The recipe and other technique parameters of the coating were revealed and investigated. Experiments indicate that the coating performs well as an antifouling agent and can be applied to various ceramic products. By using scanning electron microscope (SEM) to inspect the surface of a polished tile applied with the coating, the antifouling mechanism was studied and the results were explained in accordance with the penetrating and crosslinking of the macromolecules of hyperbrached polyethoxysiloxane into the microdefects on the surface of tiles. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5818–5824, 2006

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.