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Purpose – In the grid-based simulation, the resource application needed is distributed in the grid environment as grid service, and time management is a key problem in the simulation system. Grid workflow provides convenience for grid user to management and executes grid services. But it emphasizes process and no time-management, so a temporally constrained grid workflow model is pointed out based on grid flow with temporally constraint to schedule resources and manage time. Design/methodology/approach – The temporally constrained grid workflow model is distributed model: the federate has local temporal constraints and interactive temporal constraints among federates. The problem to manage time is a temporally distributed constraint satisfaction problem given deadline time and duration time of grid services. Multi-asynchronous weak-commitment search (AWS) algorithm is an approach to resolve DCSP, so a practical example of a simulation project-based grid system was presented to introduce application of Multi-AWS algorithm. Findings – The temporally constrained grid workflow is based temporal reasoning and grid workflow description about grid services. Originality/value – The new problem about scheduling resources and managing time in the grid-based simulation is pointed out; and the approach to resolve the problem is applied into a practical example. [ABSTRACT FROM AUTHOR]

The article presents a study which aims the acquisition of doubly variable precision-based knowledge rules in pansystems methodology from incomplete decision tables (IDTs). Study introduces limited tolerance and variable precision in relation in IDT to construct symmetric binary relation and variable inclusion to obtain upper and lower approximations with noises. Findings reveal that the classes of tolerance are not monotone with the attribute reduction and remains their symmetry.

The Xitieshan lead‐zinc deposit is located at the northern margin of the Qaidam Basin, Qinghai Province, China, and had developed a complete marine sedimentary‐exhalative system. Our preliminary study of ore‐forming fluids shows that fluid inclusions in quartz from altered stockwork rocks that represent the pipe facies have a wide range of temperature and salinity. The intense fluid activities are characteristics of the pipe facies of the exhalative system. Fluid inclusions in carbonates near the unstratified ore bodies hosted in the thick‐bedded marble which represents vent‐proximal facies are large in size and have moderate to high temperatures. They represent unerupted sub‐seafloor fluid activity. Fluids in altered stockwork rocks and carbonates have similar H2O‐NaCl‐CO2system, both belonging to the sedimentary‐exhalative system. The fluids migrate from the pipe facies to the unstratified ore bodies. Boiling of the fluids causes the separation of CO2vapor and liquid H2O. When the fluids migrate into the unconsolidated thick‐bedded marble, the escape of CO2, decreasing temperature and pressure as well as some involvement of seawater into the fluids result in the unmixing of fluids with high and low salinity and deposition of ore‐forming materials. The two unmixed fluids were trapped in unconsolidated carbonates and the ore‐forming materials were deposited in the unconsolidated carbonates to form the sedimentary‐exhalative type unstratified ore bodies. The ore‐forming temperature of unstratified ore bodies is up to high temperature indicating that there is a huge ore‐forming potential in its deep.

There are four deposit types related to a Permian mafic complex in northern Xinjiang, i.e., copper‐nickel sulfide deposit, vanadic titanomagnetite deposit, magnetite (‐cobalt) deposit and Cu‐Ni‐VTiFe composite deposit. The deposits are distributed spanning tectonic units with close and consecutive metallogenic ages. A transitional deposit type can occur among the end‐member deposits. Trace elements of host rocks show that they can derive from similar source area. Hence, they constitute a particular metallogenic series related to a mafic‐ultramafic complex that is also a symbol series of the post‐collisional stage of the Central Asia Metallogenic Province (CAMP). The metallogenic ages of the series are between 260 Ma and 300 Ma throughout the Permian. Unlike mineralization from a mantle plume, the metallogenic period of this series spans at least 40 Ma. Compared with related deposits of the Emeishan mantle plume, the North Xinjiang series has a similar ore‐forming element assemblage but has preferably developed Cu‐Ni sulfide deposits rather than vanadic titanomagnetite deposits. In concomitance with this series, North Xinjiang area has developed a set of syntectonic Au‐Cu‐Mo metallogenic series related to a felsic volcanic‐intrusive complex, which might indicate that there is no direct relationship with mantle plume activity. From early to late, i.e., the sequence of copper‐nickel sulfide to magnetite (‐cobalt) to vanadic titanomagnetite deposit, the host rock series evolves from mafic‐ultramafic and tholeiite series to mafic and alkalic series, the ΣREE content tends to increase with increasing of REE fractionation, and some of the trace elements (particularly LIL) also show an increasing tendency. The above evolutionary regularity possibly reflects a course where the magma source deepens and thermal interface moves down, energy gradually exhausts, and neo‐continental crust forming in the post‐collision stage tends to stabilize.

Abstract:The Heiyingshan granite and the Laohutai granite plutons exposed in the Southwest Tianshan resemble A‐type granites geochemically. Analysis shows that the both are ferron calc‐alkalic peraluminous or ferron alkali‐calcic peraluminous with a relatively high concentration of SiO2(>70%), high alkali contents (Na2O + K2O = 7.14%‐8.56%; K2O>N2O; A/CNK = 0.99‐1.20), and pronounced negative anomales in Eu, Ba, Sr, P and Ti. A SHRIMP zircon U‐Pb age of 285±4 Ma was obtained for the Heiyingshan hornblende biotite granite intrusion. The geochemical and age dating data reported in this paper indicate that these granites were formed during the post‐collisional crustal extension of the Southwest Tianshan orogenic belt, in agreement with the published data for the granites in the South Tianshan.

Abstract With the TEM and physical gas adsorption techniques, porous properties of nano‐fibriform silica (MLD: 92.73%) from natural chrysotile are studied in this paper. The results indicate that porous nano‐fibriform silica results from brucite octahedral sheets of nature chrysotile dissolved completely and Si‐O tetrahedral sheets collapsed by acid leaching. Its length is at a micron or nanometer scale. There are two types of pores: pores among neighboring fibers and pores in nanofiber. These pores (less than 6.5 nm in diameter, mostly 2.1 nm and 3.8 nm) all belong to mesopores. The pores in fibers consist of those among SiO2particles, those among aggregates, remnant nanotubes and capillary tubes. Nano‐fibriform silica proves better than the traditional silica as a carrier of catalyzer and a filler for reinforce rubber and plastics.

Abstract On the basis of the study on the REE geochemistry of the ore minerals and host rocks of the Kalatongke Cu‐Ni deposit, Xinjiang, it is indicated that the major ore minerals, sulfides, were sourced from the host mafic‐ultramafic magma. Characterized by low REE content of sulfide, such a Cu‐Ni sulfide deposit occurring in the orogen is obviously different from that on the margin of the craton. Because the mafic‐ultramafic rocks from the Cu‐Ni sulfide deposit occurring in the orogen is water‐rich and the REEs of some sulfides show a particular “multiple‐bending” pattern, which suggests coexistence of multiple liquid phases (fluid and melt), the sulfide melt possibly contains a great deal of hydrothermal fluids and increasingly developed gases and liquid‐rich ore‐forming fluids after the main metallogenic epoch (magmatic segregation stage).

Abstract According to the study on the peripheral orogenic belts of the Junggar basin and combined with the interpretation of geophysical data, this paper points out that there is an Early Paleozoic basement of immature continental crust in the Junggar area, which is mainly composed of Neoproterozoic‐Ordovician oceanic crust and weakly metamorphosed covering sedimentary rocks. The Late Paleozoic tectonism and mineralization were developed on the basement of the Early Paleozoic immature continental crust. The Junggar metallogenic province is dominated by Cr, Cu, Ni and Au mineralization. Those large and medium‐scale deposits are mainly distributed along the deep faults and particularly near the ophiolitic mélange zones, and formed in the Late Paleozoic with the peak of mineralization occurring in the Carboniferous‐Permian post‐collisional stage. The intrusions related to Cu, Ni and Au mineralization generally have low Isrand positive ɛENd(t) values. The δ34S values of the ore deposits are mostly near zero, and the lead isotopes are mostly of normal lead. All these indicate that the ore‐forming material comes either directly from the mantle‐derived magma (for chromite and Cu‐Ni deposits) or from recirculation of the basement material of the Early Paleozoic immature crust (for most Cu and Au deposits).

Abstract The Hatu large gold deposit is located on the western margin of the Junggar basin, Xinjiang. Its mineralization is characterized by auriferous quartz veins and Au‐bearing altered fracturing zones. Studies on mineralogy, inclusions and decrepitation temperature indicate that the gold deposit was formed by overlapping of two kinds of fluid of different origins, instead of gradual evolution of a single fluid. The auriferous quartz veins are related to magmatism‐originated fluid, but the Au‐bearing altered fracturing zones to deep‐derived fluid. Bonanzas in quartz veins were formed and localized at overlapping positions of two types of fluid under intensive compression.

For the first time, fluid‐melt inclusions are found in fluorite of the Huanggangliang skarn iron‐tin deposit (HSID). The fluorite was formed in the main stage of mineralization, named the hydro‐skarnization stage. The inclusions contain various components such as Fe, Mg and Cr from deep sources. The melts of primary inclusions are mainly Ca‐ and F‐rich and those of secondary inclusions tend to become Si‐rich. During this evolution process, the melts and iron daughter minerals decreased and even vanished. These facts reveal that the evolution of the primary mineralizing fluids and the differentiation of the fluids and melts are the main factors leading to the deposition of Fe, Sn and other elements. This discovery confirms the magmatic genesis of the HSID and has filled in the gaps in the research of magmatogenic skarn deposits and furnished new methods for such research. Furthermore, it has enlarged the scope of the research on fluid inclusions.

A thin ion-plated Ti film on sintered Si3N4was implanted with 110 keV N+at doses of 1 x 1016to 3 x 1017ions cm-2and a substrate temperature of 60°C. The adhesion of the ion-plated Ti film and the N+-implanted films on Si3N4was examined using a scratch tester and a scanning electron microscope. The interfacial chemistry of the N+-implanted Ti/Sl3N4specimens was examined using sample tilting diffraction (STD), Auger electron spectroscopy (AES), and X-ray photoelectron spectroscopy (XPS). It was found that at a dose of 3 x 1017N+cm-2, the critical load for the scratch test on the N+-implanted Ti film/Si3N4substrate increased from 10.8 to 50.0 N; consequently, the implanted films were not easily removed by interfacial failure as in the case of the unimplanted one. AES indicated that N+implantation produced substantial interfacial mixing and interfacial grading in the Ti/Si3N4system. The STD and XPS analyses revealed that a TixN (x = 1, 2) compound was formed by N+implantation. The combination of these effects in the N+implanted Ti/Si3N4specimen provided an increased adhesion that was approximately 4.6 times that of the unimplanted system. In addition, the hydrocarbon adsorbed in the near-surface region of Ti films reduced the adhesion component of friction between the metal and the N+-implanted specimen.

The article describes China's role in the petrochemical industry. The country will continue to use a variety of refined products and condensate to produce ethylene but will soon become a net importer of naphtha which is projected to be a predominant feedstock in the next 10 years. Major international oil companies that have formed joint ventures with China to build large ethylene plants include BASF, Shell and Saudi Aramco.