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This study presents new geochronological, whole-rock geochemical, and zircon Hf isotopic evidence for the age, petrogenesis, and source of Mesozoic granitic rocks of the Xing'an Block, Northeast China. This evidence reveals the Late Mesozoic tectonic evolution of the eastern section of the Central Asian Orogenic Belt. Laser-ablation inductively coupled plasma--mass spectrometryzircon U-Pb age data indicate that the syenogranite, monzogranite, and alkali feldspar granite units, as well as their associated diorite microgranular enclaves, were emplaced between 150-142 Ma, providing evidence of Late Jurassic to Early Cretaceous magmatic events within the Xing'an Block. The granites contain high concentrations of Si[O.sub.2] (65.24%-75.73 wt.%) and [K.sub.2]O (3.94%-5.30 wt.%), low concentrations of MgO (0.10%-1.30 wt.%), and A/CNK values of 0.92-1.06. In addition, Hf isotopic analysis of zircons from the 150-142 Ma granites yields [[epsilon].sub.Hf](t) values of +4.54 to +12.16 and two-stage Hf model aged from 906 to 423 Ma, indicating that they formed from magmas generated by partial melting of a juvenile Neoproterozoic--Phanerozoic accreted crustal source. The basic magma source for the diorite microgranular enclaves most likely formed from partial melting of a depleted mantle that had been metasomatized by subduction-related fluids. Combining these new geochemical data with the geology of this region, Late Jurassic to Early Cretaceous magmatism in the Xing'an Block most likely occurred in an extensional environment associated with closure of the Mongol--Okhotsk Ocean. L'article présente de nouvelles données géochronologiques, géochimiques sur roche totale et d'isotopes de Hf dans des zircons sur l'âge, la pétrogenèse et la source de roches magmatiques mésozoïques du bloc de Xing'an (nord-est de la Chine). Ces données révèlent l'évolution tectonique au Mésozoïque tardif de la section est de la ceinture orogénique d'Asie centrale. Des données de datation U-Pb sur zircon par LA-ICP-MS indiquent que les unités de syénogranite, de monzogranite et de granite à feldspath alcalin, ainsi que les enclaves microgranulaires de diorite qui leur sont associées, ont été mises en place entre 150 Ma et 142 Ma, ce qui fournit des preuves d'épisodes magmatiques d'âge jurassique tardif à crétacé précoce dans le bloc de Xing'an. Les granites présentent de fortes concentrations de Si[O.sub.2] (65,24 %-75,73 % en poids) et en [K.sub.2]O (3,94 %-5,30 % en poids), de faibles concentrations de MgO (0,10 %-1,30 % en poids), et des rapports A/CNK de 0,92-1,06. L'analyse des isotopes de Hf dans les zircons des granites de 150-142 Ma donne en outre des valeurs de [[epsilon].sub.Hf](t) de +4,54 à +12,16 et des âges de Hf pour un modèle à deux étapes de 906 Ma à 423 Ma, ce qui indique que les granites se sont formés à partir de magmas produits par la fusion partielle d'une source crustale accrétée d'âge néoprotérozoïque-phanérozoïque. La source de magma basique pour les enclaves de diorite microgranulaire s'est vraisemblablement formée par la fusion partielle d'un manteau appauvri métasomatisé par des fluides associés à la subduction. En combinant ces nouvelles données géochimiques à la géologie de larégion, il ressort que le magmatisme d'âge jurassique tardif à crétacé précoce dans lebloc de Xing'an est probablement survenu dans un milieu d'extension associé à la fermeture de l'océan Mongol-Okhotsk. [Traduit par la Rédaction], 1. Introduction The Central Asian Orogenic Belt, located between the Siberia and North China cratons and extending from the Ural Mountains in the west to the Pacific coast in the [...]

There is increasing evidence that low family socioeconomic status (SES) not only is a social issue, but also is a precursor to addiction to social media and other technologies. The authors investigated the relationship between family SES, stress, impulsiveness and inhibitory control, and social media addiction among Chinese female college students. The findings revealed that in lower-SES families, increased social media addiction was associated with reduced inhibitory control and increased stress and impulsiveness. A structural equation model was used to examine the mediation model hypothesis, and the results confirmed the mediating role of no-planning impulsiveness and inhibitory control between family educational level and social media addiction among Chinese female college students. These findings demonstrate the importance of reducing impulsiveness and improving inhibitory control for preventing social media addiction in female college students of low SES. Future studies are required to confirm precursors to social media addiction, elucidate causal mechanisms, and support the explanatory model of social media addiction. [ABSTRACT FROM AUTHOR]

Controversy has long surrounded the tectonic framework and evolution of the Mudanjiang Ocean between the Bureya-Jiamusi-Khanka Massif and Songnen-Zhangguangcai Range Massif, which are located in the easternmost segment of the Central Asian Orogenic Belt. To address these issues, we present zircon U-Pb ages, geochemical data, and zircon Hf isotopic compositions of the Taipinggou amphibolite and metagabbro exposed along the boundary area of Bureya-Jiamusi Massif and Songnen-Zhangguangcai Range Massif. Magmatic zircons from the amphibolite and metagabbro yield 206Pb/238U ages of 267 ± 2 Ma and 264 ± 2 Ma, respectively, which are interpreted as protolith ages. The geochemical data of the amphibolite samples show transitional characteristics of calcalkaline to tholeiitic series, with high MgO concentrations (9.44-10.48 wt.%) and Mg-numbers (73-75). These samples are enriched in large ion lithophile elements (e.g. Rb, Ba, and K) and light rare earth elements and are depleted in high-field-strength elements (e.g. Nb, Ta, and Ti) and heavy rare earth elements, with εHf(t) values of −6.63 to −3.26. It is inferred that the parental magma originated from an enriched lithospheric mantle that had been metasomatized by fluids derived from subducted oceanic slab. During magma evolution, the magma that formed the amphibolite mainly experienced accumulation with a shallow-level evolutionary process involving fractional crystallization. The Taipinggou metagabbro samples are subalkaline series and also characterized by enrichment in large ion lithophile elements (e.g. Rb, Ba, and K) and light rare earth elements and by depletion in Nb-Ta-P-Ti, with εHf(t) values of −3.09 to +1.16. The Taipinggou metagabbro and amphibolite have similar geochemical and Hf isotopic compositions, indicating a common parental magma source but with different degrees of magmatic differentiation. Based on the new geochronological and geochemical data presented in this study, we propose that both the Taipinggou metagabbro and amphibolite formed in a Middle Permian continental arc setting, closely related to eastward subduction beneath the Bureya-Jiamusi Massif. Combined with previous studies and regional geological observations, we suggest that a double-side subduction model is favoured for the Late Palaeozoic-Early Mesozoic geodynamic processes along the boundary area of Bureya-Jiamusi-Khanka Massif and Songnen-Zhangguangcai Range Massif. [ABSTRACT FROM AUTHOR]

To reduce the energy consumption and solve the problems of serious leakage, frequent bursting of pipes and uneven pressure distribution in water distribution system of mountainous urban, a model for dividing districts and optimization is built. Based on systematized study of water distribution system of mountainous urban, a two-step method is proposed for optimizing the built water distribution system. In the first step, the built network is districted by the algorithm proposed in this paper; in the second step, every sub-district is optimized by NSGA-II. In district algorithm, the elevation difference value between two nodes is taken as the characteristic value of corresponding pipe in pipe network. Whether a node in a pipe is classified as one subdistrict depends on that the characteristic values between the node and other nodes in this sub-district is within a given maximum allowable elevation difference. The optimization of pipe diameter in every sub-district is solved by NSGA-II, which has been successfully used in many multi-objective eases. In the process of evolution, the direction of mutation is that the diameter of every pipe approximates its economic pipe diameter. A practical dividing district and optimization of water distribution system is made by concerned calculation programs. And the results show that the energy consumption is reduced greatly and the pressure distribution of water distribution system is more even by proposed method. [ABSTRACT FROM AUTHOR]

Abstract: Ant colony algorithm is not only easy to fall into premature and stagnation, but also its convergence speed is slow in solving multiple constrained QoS unicast routing problems. Therefore, an improved ant colony algorithm embedded chaotic selections is proposed in this paper to solve multiple constrained QoS unicast routing problems. There are three aspects to improve the Ant Colony Optimization (ACO) algorithm:chaos perturbation is used to improve nodes selection strategy; adjusting dynamically evaporation coefficient according to the intensity of pheromone trail; Updating adaptively pheromone trail on the path according to the solution. According to simulations, it is demonstrate that the improved algorithm can keep good balance between accelerating convergence and preventing premature and stagnation. The improved algorithm is feasible and effective. [Copyright &y& Elsevier]

The Beiya gold deposit is located in the central part of the Jinshajiang–Honghe strike–slip belt, at the junction zone of the Tethys-Himalaya orogenic belt and the Yangtze plate in SW China. This large-scale (125.6 million metric tonnes with a mean grade of 2.42 g/t) Au-rich polymetallic deposit is related to alkaline porphyry intrusions. Previous studies show that the Beiya alkaline porphyry intrusions are the fractionation product of a mantle-derived magma emplaced in an extension environment at the post-collision stage of the India–Eurasian plate collision; the Beiya deposit is considered to be skarn-related. Based on detailed field studies and previous work, we propose that the Beiya porphyry and associated Au-rich polymetallic ores were formed by the emplacement of magmas within the Jinshajiang–Honghe strike–slip fault during the late stage of the India–Eurasian plate collision at 45–25 Ma. At Beiya, the mineralized zones in the Cu–Au-rich porphyries are surrounded by Au–Cu–Fe skarns and Au (Cu) veins. Pb–Zn–Ag-rich mineralization was derived from the inner porphyry, and is widely developed outside the central alkaline-rich porphyry. The sulfur isotope signature of the sulfide mineralization in the Beiya and Qinhe deposits is − 2.40‰–4.50‰ and 1.25–2.75‰, respectively. These values are close to 0‰, indicating that the sulfur may be mantle-derived. The δ 18 O compositions of the ore-forming fluids responsible for the formation of calcites at Qinhe are 8.10‰–9.61‰, which is lower than that of Beiya (δ 18 O = 10.5‰) where the ores contain a larger contribution of oxygen from the mantle. The Beiya porphyry magmas provided fluids and the heat that drove the transport of the metals to the site of deposition. Alkaline porphyries are widely distributed throughout the Jinshajiang–Honghe strike–slip fault belt, and they are potential hosts to future discoveries of Beiya-style mineralization. [ABSTRACT FROM AUTHOR]