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Trace element partitioning between coesite and hydrous silicate melt has been investigated at 5 GPa and 1500−1750°C. High-P experiments successfully produced large coesite crystals in equilibrium with large silicate melt pools (plus kyanite and corundum crystals in some cases). Scanning electron microscopy and micro-Raman spectroscopy were employed to characterize the phases and the textures. Wavelength-dispersive electron microprobe analyses were performed to quantify conventional major elements, and laser ablation-inductively coupled plasma-mass spectrometry analyses were successfully conducted to quantify trace elements. Eventually, high-P partition coefficients were obtained for 33 elements. In general coesite is a very pure phase. With a few possible exceptions like Sc, Ti, and V, nearly all other trace elements are incompatible in coesite. Moreover, the partitioning behaviors of nearly all trace elements except some 4+ cations cannot be readily described by the lattice strain model, presumably implying a minor role for the cation size in the trace-element partitioning. Combining our experimental results with the results in the literature, some T and P effects on the element partitioning behavior have been observed: T seemingly has different effects on different trace elements, but P might negatively correlate with the partition coefficients in all cases. Due to its large modal fraction in some subducted materials such as the continental crustal material, coesite might play an important role in the distributions of some trace elements, Ti for example.

The Circum-Pacific subduction zone is a famous gold metallogenic domain in the world, with two important gold metallogenic provinces, the North China Craton and Nevada, which are related to the destruction of the North China Craton and the Wyoming Craton, respectively. Their ore-forming fluids were possibly derived from the stagnant slab in the mantle transition zone. The oceanic lithospheric mantle usually contains serpentine layers up to thousands of meters thick. During plate subduction, serpentine is dehydrated at depths of 300 km. The overlying big mantle wedge is hydrated during the breakdown of these hydrous facies in the mantle transition zone. The dehydration of the subducted slab in the big mantle wedge releases sulfur-rich fluid, which extracts gold and other chalcophile elements in the surrounding rocks, forming gold-rich fluid. Because the cratonic geotherm is lower than the water-saturated solidus line of lherzolite, the fluid cannot trigger partial melting. Instead, it induces metasomatism and forms pargasite and other water-bearing minerals when it migrates upward to depths of less than 100 km in the cratonic lithospheric mantle, resulting in a water- and gold-rich weak layer. During the destruction of craton, the weak layer is destabilized, releasing gold-bearing fluids that accelerate the destruction. The ore-forming fluids migrate along the shallow weak zone and are accumulated at shallow depths, and subsequently escape along deep faults during major tectonic events, leading to explosive gold mineralization. The ore-forming fluids are rich in ferrous iron, which releases hydrogen at low pressure through iron hydrolysis. Therefore, decratonic gold deposits are often reduced deposits.

In-situ hydrothermal experiments using diamond-anvil cell show that sulfate and sulfide are the dominant sulfur species under P-T conditions similar to those of porphyry magmas. No sulfite was identified using in-situ Raman spectrometer. This supports that porphyry copper mineralization is controlled by sulfate reduction, rather than sulfite disproportionation.

Atherosclerosis (AS) is a leading cause of vascular diseases that severely threats the human health due to the lack of efficient therapeutic methods. During the development and progress of AS, macrophages play critical roles, which are polarized into pro-inflammatory M1 phenotype to excrete abundant cytokines and overproduce reactive oxygen species (ROS), and take up excess amount of lipid to form foam cells. In this work, we developed a MnO2-based nanomedicine to re-educate macrophages for targeting AS therapy. The MnO2 was one-pot synthesized under mild condition, showing intrinsic catalase-mimic activity for self-oxygenation by using endogenous H2O2 as substrate. Moreover, the mesoporous structure as well as the abundant metal coordination sites in MnO2 structure facilitated the loading of an anti-AS drug of curcumin (Cur), achieving extraordinarily high drug loading capacity of 54%. Cur displayed a broad spectrum of anti-oxidant and anti-inflammatory capabilities to repolarize M1 macrophages into M2 phenotype, and the catalytic MnO2 recovered the function of lipid efflux transporter to remove lipid from cells by suppressing HIF-1α. Collectively, the nanocarrier and the payload drug functioned as an all-active nanoplatform to synergistically alleviate the syndromes of AS. In ApoE−/− mice model, the nanosystem could significantly prolong the circulation half-life of Cur by sixfold, and enhance drug accumulation in atherosclerotic lesion by 3.5-fold after intravenous injection by virtue of surface hyaluronic acid (HA) modification. As a result, a robust anti-AS efficacy was achieved as evidenced by the decrease of atherosclerotic lesion, plaque area, lipid level. Graphical Abstract

The Late Ordovician mass extinction (LOME) was the first global extinction with the destruction of 85 % of marine species. However, the cause of LOME is still controversial. Most studies attribute it to large-scale volcanism caused by global cooling or warming. Through analyzing the driving difference between global cooling and warming on large-scale magmatism, the perspective is intended to evoke a hot discussion on the cause of LOME. Did global cooling or warming trigger the LOME?

The Indo-Pacific convergence region is the best target to solve the two remaining challenges of the plate tectonics theory, i.e., subduction initiation and the driving force of plate tectonics. Recent studies proposed that the Izu-Bonin subduction initiation belongs to spontaneous initiation, which implies that it started from extension, followed by low angle subduction. Numerical geodynamic modeling suggests that the initiation of plate subduction likely occurred along a transform fault, which put the young spreading ridge in direct contact with old oceanic crust. This, however, does not explain the simultaneous subduction initiation in the west Pacific region in the Cenozoic. Namely, the subduction initiations in the Izu-Bonin- Mariana, the Aleutian, and the Tonga-Kermadec trenches are associated with oceanic crusts of different ages, yet they occurred at roughly the same time, suggesting that they were all triggered by a major change in the Pacific plate. Moreover, low angle subduction induces compression rather than extension, which requires external compression forces. Given that the famous Hawaiian-Emperor bending occurred roughly at the same time with the onset of westward subductions in the west Pacific, we propose that these Cenozoic subductions were initiated by the steering of the Pacific plate, which are classified as induced initiation. Induced subduction initiation usually occurs in young ocean basins, forming single-track subduction. The closures of Neo-Tethys Oceans were likely triggered by plumes in the south, forming northward subductions. Interestingly, the Indian plate kept on moving northward more than 50 Ma after the collision between the Indian and Eurasian continents and the break-off of the subducted oceanic slab attached to it. This strongly suggests that slab pull is not the main driving force of plate tectonics, whereas slab sliding is.

Levulinic acid (LA) is an important biomass-based chemical. The preparation of LA from bagasse is of great practical significance for the comprehensive and efficient utilization of biomass. Biomass bagasse is mainly composed of cellulose, hemicellulose, and lignin. The cellulose is mainly degraded to glucose, and hemicellulose is mainly degraded to xylose, with dilute acid treatment at high temperature. In this research, we produced the LA from bagasse with dilute acid treatment at high temperature. The influences of residence time (10–60 min), reaction temperature (170–240 °C), liquid-to-solid ratio (5:1–25:1 mL/g), and acid concentration (1–5%) on the synthesis of LA were investigated by statistical methods, achieving a maximum LA yield of 16.25%. Additionally, LA was isolated and extracted from bagasses hydrolysate by ion exchange and vacuum distillation. The adsorption capacity of different resins was determined and compared. The optimal resin to acquire better adsorption capacity was determined. The better adsorption capacity was obtained when the D301 resin was selected as the filter for ion exchange. The height-to-diameter rate, eluent flow rate, elution volume of ion exchange column were 10, 0.84 BV/h, 56.4 mL, respectively. The eluent was then distilled under vacuum, collecting the components at 130–140 °C. The total yield and purity of LA were 67.1% and 78%, respectively.

The mechanism of lithospheric removal and destruction of the North China Craton (NCC) has been hotly debated for decades. It is now generally accepted that the subduction of the (Paleo)-Pacific plate played an important role in this process. However, how the plate subduction contributed to the craton destruction remains unclear. Here we report high oxygen fugacity (fO2) characteristics of the Yunmengshan granite, e.g., hematite–magnetite intergrowth supported by zircon Ce4+/Ce3+ ratios and apatite Mn oxygen fugacity indicator. High fO2 magmas are widely discovered in Late Mesozoic (160–130 Ma) adakitic rocks in central NCC. The origin of high fO2 magma is likely related to the input of the “oxidized mantle components”, which shows a close connection between plate subduction and destruction of the craton. The research area is ~ 1500 km away from the current Pacific subduction zone. Considering the back-arc extension of Japan Sea since the Cretaceous, this distance may be shortened to ~ 800 km, which is still too far for normal plate subduction. Ridge subduction is the best candidate that was responsible for the large scale magmatism and the destruction of the NCC. Massive slab-derived fluids and/or melts were liberated into an overlying mantle wedge and modified the lithospheric mantle. Rollback of the subducting plate induced the large-scale upwelling of asthenospheric mantle and triggered the formation of extensive high fO2 intraplate magmas.

Plate subduction is the largest natural factory that processes elements, which controls recycling and mineralization of a variety of elements. There are three major ore deposit belts in the world: the circum-Pacific, the central Asian, and the Tethys belts. All the three belts are closely associated with plate subductions, the mechanism remains obscure. We approached this problem from systematic studies on the behaviours of elements during geologic processes. This contribution summaries the recent progress of our research group. Our results suggest that porphyry Cu deposits form through partial melting of subducted young oceanic crust under oxygen fugacities higher than ΔFMQ ∼+1.5, which is promoted after the elevation of atmospheric oxygen at ca. 550 Ma. Tin deposits are associated with reducing magmatic rocks formed as a consequence of slab rollback. The Neo-Tethys tectonic regime hosts more than 60% of the world’s total Sn reserves. This is due to the reducing environment formed during the subduction of organic rich sediments. For the same reason, porphyry Cu deposits formed in the late stages during the closure of the Neo-Tethys Ocean. Tungsten deposits are also controlled by slab rollback, but is not so sensitive to oxygen fugacity. Subduction related W/Sn deposits are mostly accompanied by abundant accessory fluorites due to the breakdown of phengite and apatite. Decomposition of phengite is also significant for hard rock lithium deposits, whereas orogenic belt resulted from plate subduction promote the formation of Li brine deposits. Cretaceous red bed basins near the Nanling region are favorable for Li brines. Both Mo and Re are enriched in the oxidation-reduction cycle during surface processes, and may get further enriched once Mo-, Re-enriched sediments are subducted and involved in magmatism. During plate subduction, Mo and Re fractionate from each other. Molybdenum is mainly hosted in porphyry Mo deposits and to a less extent, porphyry Cu-Mo deposits, whereas Re is predominantly hosted in porphyry Cu-Mo deposits and sedimentary sulfide deposits.

The kinetics of serpentinization were investigated at 400–500 °C and 3.0–20 kbar using natural olivine and peridotite for run durations of 9–38 days. The serpentine varieties were lizardite for all the experiments. The serpentinization kinetics at 400 °C and 3.0 kbar and at 500 °C and 20 kbar displayed a sigmoidal kinetic behavior, with very sluggish reaction rates at the early stage of serpentinization, followed by a sudden increase in the reaction rates. They were 1–2 orders of magnitude faster than serpentinization kinetics commonly used for modeling serpentinization-related processes. Pressure greatly increases the rates of peridotite serpentinization at 500 °C, e.g., 19% of reaction extent was achieved within 20 days for experiments at 500 °C and 3.0 kbar with starting grain sizes of

Phosphorescent organic light emitting diodes (PHOLEDs) have been fabricated with structure of indium tin oxide/MoO3 doped 4,4′-N,N'-dicarbazole-biphenyl (CBP) 30 nm/tris(4-carbazoyl-9-ylphenyl)amine 10 nm/CBP doped with tris(2-phenylpyridine)iridium(III) (CBP:Ir(ppy)3) x/bathocuproine 50 nm/LiF 1 nm/Al, where x = 2.5, 5, 10, and 20 nm, respectively. The current efficiency (CE) of device with x = 10 nm is higher than those with x = 2.5 and 5 nm, mostly because the width of exciton formation zone (5.7 nm) with x = 10 nm is larger than those (2.5 and 5 nm) with x = 2.5 and 5 nm. However, the current density with x = 10 nm decreases than those with x = 2.5 and 5 nm at a certain driving voltage, since the ~ 4.3 nm CBP:Ir(ppy)3 accommodating no exciton formation with x = 10 nm plays a role of transporting holes, raising ohmic loss of hole and thereby increasing driving voltage. When x increases from 10 to 20 nm, the width of exciton formation zone rises from 5.7 to 6.8 nm with CE almost unchanged, and the current density decreases as a result of increased ohmic loss of hole. The current research is useful to develop high-efficiency and low-driving voltage PHOLEDs.

Application of microbial fermentation of xylose to produce xylitol can not only turn waste into useful products and conserve resources, but also protect the environment. Currently, more than 100 kinds of microorganisms are known to ferment xylose, among which Candida tropicalis has strong xylose conversion ability and high tolerance to inhibitors such as furfural, acetate, and phenolics in xylose mother liquor. The present study focused on fermenting xylose hydrolysate from sugarcane bagasse to produce xylitol using C. tropicalis strain 31949. The effects of inoculum age, inoculum quantity, and initial xylose concentration on xylitol fermentation by C. tropicalis 31949 were discussed. The following optimum fermentation conditions were determined: inoculum quantity, 10%; inoculum age, 26 h; and initial xylose concentration, 100 g/L. Under these optimal fermentation conditions, C. tropicalis 31949 could ferment sugarcane bagasse hydrolysate, which was pretreated by vacuum concentration and activated carbon detoxification decoloration, to produce 62.9800 g/L xylitol.

Cenozoic adakitic rocks in the Gangdese changed from barren continental melts to ore-forming slab melts at ~ 23 Ma. The distribution and chemical characteristics of the ore-forming adakites point to an association with the Ninetyeast Ridge. The subduction of the thick, rigid Ninetyeast Ridge changed the geometry and rheology of the eastern Tibetan Plateau lithosphere and asthenosphere, restrained the eastward escape of asthenospheric mantle as well as continental fragments, and promoted the uplift and building of the Tibetan Plateau, which consequently changed the tectonic and climatic regimes in eastern Asia.

Applications for l-lactic acid are increasing. Recent studies have investigated inexpensive raw materials for producing l-lactic acid and have explored technical principles. We optimized fermentation conditions for enzymatic hydrolysis of sugarcane bagasse as a substrate for l-lactic acid production, and to achieve a high conversion rate of bagasse to l-lactic acid using Rhizopus oryzae. The maximum conversion rate of l-lactic acid was 28.45% in the conditions of 48-h fermentation time and 200 r/min rotary shaking in 50 mL liquid medium with 10% inoculum. The kinetics of fermentation were worked out. Logistic equations, Luedeking–Piret equations and Luedeking–Piret-like equations were chosen as kinetic models. Three kinetic models were constructed which reflected microbial growth, product synthesis and substrate consumption; R2 of three kinetics model equations, respectively, were 0.9799, 0.9869, 0.9911, which indicated that the predicted values fit the experimental data and the equations accurately describe the fermentation process of R. oryzae Gim3.129 for producing l-lactic acid. The models described the fermentation process of R. oryzae Gim3.129 successfully and provided a theoretical foundation for the industrialization of l-lactic acid from sugarcane bagasse.

Granitic continental crust distinguishes the Earth from other planets in the Solar System. Consequently, for understanding terrestrial continent development, it is of great significance to investigate the formation and evolution of granite. Crystal fractionation is one of principal magma evolution mechanisms. Nevertheless, it is controversial whether crystal fractionation can effectively proceed in felsic magma systems because of the high viscosity and non-Newtonian behavior associated with granitic magmas. In this paper, we focus on the physical processes and evaluate the role of crystal fractionation in the evolution of granitic magmas during non-transport processes, i.e., in magma chambers and after emplacement. Based on physical calculations and analyses, we suggest that general mineral particles can settle only at tiny speed (~10−9–10−7 m s−1) in a granitic magma body due to high viscosity of the magma; however, the cumulating can be interrupted with convection in magma chambers, and the components of magma chambers will tend to be homogeneous. Magma convection ceases once the magma chamber develops into a mush (crystallinity, F>~40–50%). The interstitial melts can be extracted by hindered settling and compaction, accumulating gradually and forming a highly silicic melt layer. The high silica melts can further evolve into high-silica granite or high-silica rhyolite. At various crystallinities, multiple rejuvenation of the mush and the following magma intrusion may generate a granite complex with various components. While one special type of granites, represented by the South China lithium- and fluoride- rich granite, has lower viscosity and solidus relative to general granitic magmas, and may form vertical zonation in mineral-assemblage and composition through crystal fractionation. Similar fabrics in general intrusions that show various components on small lengthscales are not the result of gravitational settling. Rather, the flowage differentiation may play a key role. In general, granitic magma can undergo effective crystal fractionation; high-silica granite and volcanics with highly fractionated characteristics may be the products of crystal fractionation of felsic magmas, and many granitoids may be cumulates.

South China is famous for the extensive magmatism and polymetallic mineralization that took place there in the Mesozoic. Shilu is a large porphyry–skarn Cu–Mo deposit in the Yangchun Basin, South China. The lithology of the Shilu intrusion is granodiorite and quartz diorite, both of which are high-K calc-alkaline series, with high Sr (>400 ppm) content along with low Y and Yb contents. Most of the samples have characteristics of adakite except for a few samples that have slightly higher Y and Yb contents, which may be plausibly explained by crustal contamination. Laser Ablation Inductively Coupled Plasma Mass Spectrometry zircon U–Pb dating revealed ages between 106.6 ± 1.3 and 103.9 ± 0.5 Ma, with multiple magmatic pulses. Molybdenite Re–Os isochron age of 102.2 ± 2.9 Ma (MSWD = 9.4) was determined, which is identical to the youngest zircon U–Pb age (103.9 ± 0.5 Ma) within error. The Shilu intrusion has high oxygen fugacity as indicated by high zircon Ce4+/Ce3+ and EuN/EuN* ratios. Considering the geochemical characteristics (high Sr, and low Y and Yb contents), high oxygen fugacity, and copper mineralization of the Shilu intrusion, it was most likely formed by partial melting of a subducted young oceanic slab. Whole-rock Sr–Nd isotope-, zircon Hf isotope-, and whole-rock trace element analyses show that Shilu adakitic magmas may have interacted with type II enriched mantle and/or crustal materials during ascent. South China was affected by the Pacific tectonic regime to the east and the Neo-Tethys tectonic regime to the south in the Cretaceous. Based on the Pacific Plate drifting and rotation history, it is hard to explain how the Pacific Plate would have subducted and melted, forming adakitic rocks in the Shilu region. Considering the tectonic history of Southeast Asia and the South China Sea, the Neo-Tethys trench should have been much closer to the South China Block in the Cretaceous, and thus have had a greater impact on the South China Block. Based on the subduction direction, time of subduction, and distance between the Neo-Tethys subduction zone and the Shilu deposit, subduction of the Neo-Tethys ridge is the best mechanism for explaining the Shilu adakitic rocks and Cu–Mo mineralization.

Copper is a moderately incompatible chalcophile element. Its behavior is strongly controlled by sulfides. The speciation of sulfur is controlled by oxygen fugacity. Therefore, porphyry Cu deposits are usually oxidized (with oxygen fugacities > ΔFMQ +2) (Mungall 2002; Sun et al. 2015). The problem is that while most of the magmas at convergent margins are highly oxidized, porphyry Cu deposits are very rare, suggesting that high oxygen fugacity alone is not sufficient. Partial melting of mantle peridotite even at very high oxygen fugacities forms arc magmas with initial Cu contents too low to form porphyry Cu deposits directly (Lee et al. 2012; Wilkinson 2013). Here we show that partial melting of subducted young oceanic slabs at high oxygen fugacity (>ΔFMQ +2) may form magmas with initial Cu contents up to >500 ppm, favorable for porphyry mineralization. Pre-enrichment of Cu through sulfide saturation and accumulation is not necessarily beneficial to porphyry Cu mineralization. In contrast, re-melting of porphyritic hydrothermal sulfide associated with iron oxides may have major contributions to porphyry deposits. Thick overriding continental crust reduces the “leakage” of hydrothermal fluids, thereby promoting porphyry mineralization. Nevertheless, it is also more difficult for ore forming fluids to penetrate the thick continental crust to reach the depths of 2–4 km where porphyry deposits form.

The dependence of starting materials and their initial grain sizes on the formation of gases (H2, CH4, C2H6 and C3H8) during serpentinization was investigated by conducting hydrothermal experiments at 311°C and 3 kbar on olivine and peridotite with initial grain sizes ranging from

The Triassic eclogite-bearing central Qiangtang metamorphic belt (CQMB) in the northern Tibetan Plateau has been debated whether it is a metamorphic core complex underthrust from the Jinsha Paleo-Tethys or an in-situ Shuanghu suture. The CQMB is thus a key issue to elucidate the crustal architecture of the northern Tibetan Plateau, the tectonics of the eastern Tethys, and the petrogenesis of Cenozoic high-K magmatism. We here report the newly discovered Baqing eclogite along the eastern extension of the CQMB near the Baqing town, central Tibet. These eclogites are characterized by the garnet + omphacite + rutile + phengite + quartz assemblages. Primary eclogite-facies metamorphic pressure–temperature estimates yield consistent minimum pressure of 25 ± 1 kbar at 730 ± 60 °C. U–Pb dating on zircons that contain inclusions (garnet + omphacite + rutile + phengite) gave eclogite-facies metamorphic ages of 223 Ma. The geochemical continental crustal signature and the presence of Paleozoic cores in the zircons indicate that the Baqing eclogite formed by continental subduction and marks an eastward-younging anticlockwise West–East Qiangtang collision along the Shuanghu suture from the Middle to Late Triassic.

近10多年来LA-ICPMS锆石U-Pb定年技术得到迅速发展和应用, 其特点是成本低、分析速度快, U-Pb定年的内部精度可以优于1%, 但其外部重现性(准确度)则相对较差. 为了定量评估LA-ICPMS锆石U-Pb定年的准确性, 本文在多个SIMS和LA-ICPMS实验室对一个中生代闪长质暗色包体的锆石样品(FS06)和一个新元古代闪长岩的锆石样品(WC09-32)进行对比分析. 三台SIMS对FS06和WC09-32锆石的U-Pb分析获得了在误差范围一致的定年结果, 其最佳形成年龄分别为132.2和760.5 Ma (不确定度~1%, 2RSD). 6个LA-ICPMS实验室获得的FS06锆石的U-Pb年龄结果范围为(128.3±1.0)~(135.0±0.9) Ma(2SE), WC09-32锆石的U-Pb年龄结果范围为(742.9±3.1)~(777.8±4.7) Ma(2SE), 外部误差达到~4%(2RSD). LA-ICPMS锆石U-Pb定年的误差来源包括单点同位素比值测定时引入的误差、用标样计算分馏因子时引入的误差、普通铅校正造成的年龄误差和标准样品推荐值的误差以及数据处理及相关软件的使用. 本文的结果客观地反映了目前的LA-ICPMS分析技术对锆石U-Pb定年的不确定度水平在~4%(2RSD). 因此, 在对LA-ICPMS锆石U-Pb定年结果的解释和应用时, 必须考虑该方法的不确定度水平.

The publish/subscribe (pub/sub) paradigm is a popular communication model for data dissemination in large-scale distributed networks. However, scalability comes with a contradiction between the delivery latency and the memory cost. On one hand, constructing a separate overly per topic guarantees real-time dissemination, while the number of node degrees rapidly increases with the number of subscriptions. On the other hand, maintaining a bounded number of connections per node guarantees small memory cost, while each message has to traverse a large number of uninterested nodes before reaching the subscribers. In this paper, we propose Feverfew, a coverage-based hybrid overlay that disseminates messages to all subscribers without uninterested nodes involved in, and increases the average number of node connections slowly with an increase in the number of subscribers and nodes. The major novelty of Feverfew lies in its heuristic coverage mechanism implemented by combining a gossip-based sampling protocol with a probabilistic searching protocol. Based on the practical workload, our experimental results show that Feverfew significantly outperforms existing coverage-based overlay and DHT-based overlay in various dynamic network environments.

The Baerzhe alkaline granite pluton hosts one of the largest rare metal (Zr, rare earth elements, and Nb) deposits in Asia. It contains a geological resource of about 100 Mt at 1.84 % ZrO2, 0.30 % Ce2O3, and 0.26 % Nb2O5. Zirconium, rare earth elements (REE), and Nb are primarily hosted by zircon, yttroceberysite, fergusonite, ferrocolumbite, and pyrochlore. Three types of zircon can be identified in the deposit: magmatic, metamict, and hydrothermal. Primary magmatic zircon grains occur in the barren hypersolvus granite and are commonly prismatic, with oscillatory zones and abundant melt and mineral inclusions. The occurrence of aegirine and fluorite in the recrystallized melt inclusions hosted in the magmatic zircon indicates that the parental magma of the Baerzhe pluton is alkali- and F-rich. Metamict zircon grains occur in the mineralized subsolvus granite and are commonly prismatic and murky with cracks, pores, and mineral inclusions. They commonly show dissolution textures, indicating a magmatic origin with later metamictization due to deuteric hydrothermal alteration. Hydrothermal zircon grains occur in mineralized subsolvus granite and are dipyramidal with quartz inclusions, with murky CL images. They have 608 to 2,502 ppm light REE and 787 to 2,521 ppm Nb, much higher than magmatic zircon. The texture and composition of the three types of zircon indicate that they experienced remobilization and recrystallization during the transition from a magmatic to a hydrothermal system. Large amounts of Zr, REE, and Nb were enriched and precipitated during the transitional period to form the giant low-grade Baerzhe Zr–REE–Nb deposit.

Here we report a novel mass spectrometry measurement system (MSHE4) developed at State Key Laboratory of Isotope Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences for quantifying helium-4 contents of geological mineral samples. The MSHE4 system consists of seven units, a high vacuum level generating unit, a gas purified unit, a laser heating unit, a pneumatic valve unit, an automatic control unit, a gas standard unit and a quadropole mass spectrometer unit. The unique software package, developed using LabVIEW for embedded system, allows users to control the full measurement sequences. Results from a test of the Durango apatite sample are used to illustrate the performance of the new MSHE4. We show that the constructed MSHE4 system is able to accurately measure helium-4 contents of apatite mineral, which in turn can be used to quantify the low temperature thermochronology of geological minerals in combination with measurements of uranium and thorium by LA-ICP-MS. The configuration of the MSHE4 system has following advantages: smaller volume of pipeline for gas purification, easier operation of graphic user interface for measurements, and more compact design of sample holder for single grain measurements. The separate step-heating unit can be mounted to the system smoothly. The MSHE4 system can be used for measurement of noble gases from minerals, and in turn thermochronology applications for geochemists.

This paper describes a GIS-based application of a fuzzy analytical hierarchy process (AHP) to map porphyry-Cu prospectivity in the Dananhu metallogenic belt, NW China. Based on a model of porphyry-Cu mineralization, evidential layers were derived from geological, geochemical, and geophysical data. These layers were subsequently assigned weights by implementing a fuzzy AHP method using knowledge from three experts in porphyry-Cu exploration. After obtaining normalized weights, different fuzzy operators were tried to combine the weighted evidential layers into potential maps, which were then compared and evaluated by predication-area (P-A) plots. Subsequently, a ternary map was generated by defuzzification of the optimum prospectivity map as selected by the P-A plot; this ternary map shows zones of high, moderate, and low favorability for porphyry-Cu deposits in the study area. To further evaluate the results, potential zones were analyzed for two-dimensional spatial domain. The results demonstrate that the fuzzy AHP method can be effectively applied to mineral prospectivity mapping in vaguely known areas.

The different interactions between a chemosensor, 1-(naphthalen-2-yl)-3-(6-nitrobenzothiazol-2-yl)-thiourea (1), and F−, acetate (AcO−), Cl−, and Br− anions have been investigated theoretically at the B3LYP/6-31+G(d,p) level with the basis set superposition error (BSSE) correction. It was found that the high selectivity of compound 1 for F− can be ascribed to the ability of the anion to deprotonate the N-H fragment of the host sensor, while the chemosensor also has a strong affinity for AcO− by virtue of the formation of a hydrogen-bonded complex. Intramolecular charge transfer (ICT) causes the colorimetric signaling of compound 1 after interaction with F−/AcO−. A study of substituent effects suggested that the O/NH- and O/S-substituted derivatives are also expected to be promising candidates for chromogenic F−/AcO− chemosensors.

Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47 degrees 35'N, 133 degrees 31'E), northeast China, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of -300 to -100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.

Many large porphyry Cu-Au deposits are connected to adakitic rocks known to be closely associated with ridge subduction. For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are much less there, both in terms of tonnage and the number of deposits. Given that Cu and Au are moderately incompatible elements, oceanic crust has much higher Cu-Au concentrations than the mantle and the continental crust, and thus slab melts with their diagnostic adakitic chemistry have systematically higher Cu and Au, which is favorable for mineralization. Considering the geotherm of subducting slabs in the Phanerozoic, ridge subduction is the most favorable tectonic setting for this. Therefore, slab melting is the likely link in the spatial association between ridge subduction and Cu-Au deposits. Geochemical signatures of slab melting and hence maybe ridge subduction in less eroded regions in eastern China, the central Asian orogenic belt etc. may indicate important exploration targets for large porphyry Cu-Au deposits.

The Global boundary Stratotype Section and Point (GSSP) for the base of the Hirnantian Stage (the latest stage of the Ordovician System) is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangjiawan North Section, which is the upper most “golden spike” of the Ordovician. However, this “golden spike” is lack of reliable geochronology data. This article gives a sensitive high resolution ion microprobe (SHRIMPII) zircon U-Pb dating for a K-bentonite sample from the Kuanyinchiao Bed in the Wangjiawan North Section. The age of the K-bentonite sample is 443.2±1.6 Ma, that is to say, the isotopic age of the uppermost of Hirnantian Stage, the point of Ordovician-Silurian boundary, should be near to, but slightly younger than 443.2±1.6 Ma. This age is identical to the Ordovician-Silurian boundary age 443.7±1.5 Ma as declared by International Commission on Stratigraphy (ICS). So, this research provides some good geochronlogical data for the Hirnantian Stage and the Ordovician-Silurian boundary as well as the global correlation.

Background Our previous research showed that icariin (1) and its phosphorylated structural modification (2) improved the survival and attenuated oxidative stress and liver dysfunction induced by duck virus hepatitis. In this paper, we were one step closer to determine the structure of phosphorylation icariin (2) by the FT-IR, HRESIMS and 13C NMR. Anti-DHAV activities of 1 and 2 were compared in duck embryonic hepatocytes (DEHs) cultured in vitro and by artificial infection method in vivo. Additionally, the antiviral mechanisms of replication/release in vitro and the DHAV gene expression in vivo of 1 and 2 were analyzed. Results Compound 2's molecular formula was C33H42O18P. The results indicated that 1 and 2 effectively resisted DHAV invading DEHs, that they decreased the mortality of ducklings challenged with DHAV, and that 2 performed more effectively. 1 and 2 performed evenly on DHAV release; however, 2 restrained virus replication far more effectively. Since the anti-DHAV mechanisms of 1 and 2in vitro probably involve suppression of replication and release, 2’s better performance in anti-DHAV may result from its far more effectively inhibiting virus replication. Conclusions The compound 2's chemical structure was defined as 8-prenylkaempferol-4'-methylether-3-rhamnosyl-7-(6'''-phosphate)-glycoside. 1 and 2 exhibited anti-virus activity on DHAV. Our results suggest that 1 and 2 might become an anti-virus plant material candidate.

Yulong ore-bearing porphyries, along the northwestern extension of the Red River–Ailao Shan fault system in eastern Tibet, consist of five porphyry deposits, containing a total of more than 8 million tons of copper resources. U–Th–Pb laser inductively coupled plasma mass spectrometry dating of zircon shows that the porphyries were emplaced in Early Tertiary (41.2–36.9 Ma), covering a period of ∼4.3 Ma, with formation ages decreasing systematically from northwest to southeast. The start of porphyry magmatism coincided with the onset of transpressional movement along the Red River–Ailao Shan fault system, implying a close link between these two events. Age sequence in intrusions can be plausibly explained by assuming that a region of melting in the lower northwestern plate moved southeasternward along the Tuoba–Mangkang fault relative to the upper plate. Zircon grains from the Yulong ore-bearing porphyries have higher Ce4+/Ce3+ than those from barren porphyries in the region. This suggests that the ore-bearing porphyries crystallized from a relatively oxidized magma, which has important implications for future ore exploration in the region and other Cu deposits in convergent margin environments in general.

China is striving to start its own cane and sugar based green chemical industry. A survey of current progress and situation in this new boundary in China was made. The comprehensive utilization of byproducts from cane, and sugar-based new products development were summarized. The research and industrial application of new products and technologies in this field are also discussed.

Variations in the 187Os/188Os isotopic signature of mantle and mantle-derived rocks have been thought to provide a powerful chemical tracer of deep Earth structure. Many studies have inferred from such data that a long-lived, high-rhenium component exists in the deep mantle (187Re is the parent isotope decaying to 187Os, with a half-life of approximately 42 billion years), and that this reservoir probably consists of subducted oceanic crust. The interpretation of these isotopic signatures is, however, dependent on accurate estimates of rhenium and osmium concentrations in all of the main geochemical reservoirs, and the crust has generally been considered to be a minor contributor to such global budgets. In contrast, we here present observations of high rhenium concentrations and low Yb/Re ratios in arc-type melt inclusions. These results indicate strong enrichment of rhenium in undegassed arc rocks, and consequently the continental crust, which results in a crustal estimate of 2 p.p.b. rhenium, as compared to previous estimates of 0.4-0.2 p.p.b. (refs 4, 5). Previous determinations of rhenium in arc materials, which were largely measured on subaerially erupted samples, are likely to be in error owing to rhenium loss during degassing. High mantle-to-crust rhenium fluxes, as observed here, require a revaluation of geochemical models based on the 187Re-187Os decay system.

The basalt-borne peridotite xenoliths from Jiangsu-Anhui provinces were analyzed for whole rock Os isotopic compositions in two laboratories of USTC, China and CRPG, France, respectively. The 187 Os/ 188 Os ratio of the sample set ranges from 0.119 to 0.129 (25 samples, USTC) and from 0.117 to 0.131 (17 samples, CRPG). The Os isotopic compositions of most samples are less than 0.129 and depleted relatively to the primitive mantle, showing a good correlation with the major element compositions. With the 187 Os/ 188 Os-Al 2 O 3 alumichron, the samples yield a model age of 2.5 ± 0.1 Ga (data of USTC) and 1.9 ± 0.1 Ga (data of CRPG), late Archean to early Proterozoic. The two samples with the lowest 187 Os/ 188 Os ratio (0.119 and 0.117) have the T RD (Re depleted age) of 1.1 Ga (USTC) and 1.4 Ga (CRPG), mid-Proterozoic. The Os isotope model age shows that the peridotite xenoliths from Cenozoic alkali basalt in Jiangsu-Anhui provinces have an old formation age (early- to mid- Proterozoic). They are not newly produced mantle after the Phanerozoic replacement of the lithosphere mantle, but residual fractions of Proterozoic mantle.

There are two generations of white micas in retrograded coesite-bearing eclogite from the Yangkou area near Qingdao, eastern China. The secondary phengite developed along the folliations in eclogite is the majority of the white micas. Nd and Sr isotopic disequilibriums between garnet and retrograded omphacite as well as secondary phengite have been observed. Consequently, the Rb-Sr ages ((193 ±4) Ma-(195 ±4) Ma) given by the tie lines of the secondary phengite + garnet or whole rock may predate the formation time of the phengite. The Rb-Sr age of (183 ±4) Ma given by the secondary phengite + retrograde omphacite is much closer to the formation time of the phengite indicating the retrograde age of eclogite instead of a cooling age of eclogite at 500°C.

The conflict among water drainage, water supply and eco-environment protection is getting more and more serious due to the irrational drainage and exploitation of ground water resources in coal-accumulated basins of North China. Efficient solutions to the conflict are to maintain long-term dynamic balance between input and output of the ground water basins, and to try to improve resourcification of the mine water. All solutions must guarantee the eco-environment quality. This paper presents a new idea of optimum combination of water drainage, water supply and eco-environment protection so as to solve the problem of unstable mine water supply, which is caused by the changeable water drainage for the whole combination system. Both the management of hydraulic techniques and constraints in economy, society, ecology, environment, industrial structural adjustments and sustainable developments have been taken into account. Since the traditional and separate management of different departments of water drainage, water supply and eco-environment protection is broken up, these departments work together to avoid repeated geological survey and specific evaluation calculations so that large amount of national investment can be saved and precise calculation for the whole system can be obtained. In the light of the conflict of water drainage, water supply and eco-environment protection in a typical sector in Jiaozuo coal mine, a case study puts forward an optimum combination scheme, in which a maximum economic benefit objective is constrained by multiple factors. The scheme provides a very important scientific base for finding a sustainable development strategy.

Using the isotopic diluting and thermal ionization mass spectrometric (TIMS) technique, the U-series dating procedure was established on the basis of measurement of national standard GBW04412. With this highly precise technique the Holocene corals from the South China Sea were dated. Comparison between this method and α-spectrometry was made. The results show that a thriving period of corals in the South China Sea appeared at 6 800–5 800 a BP, during which the paleosea level was the higher than at present in the Holocene.

The osmium isotopic ratio of187Os/188Os ranging from 0.126 to 0.127 for the primitive upper mantle (PUM) is obtained according to the correlation between187Os/188Os and Al2O3 of mantle-derived xenoliths and orogenic peridotites, which consists with Allegre and Luck’s ALM value and similar to Yin’s nuggets uniform reservoir (NUR) value. It shows that the Os isotope ratio is lower than enstatite or ondinary chondrites, similar to carbonaceous chondrites (CV3).

Two national stalagnlite standards (GBW04412, GBW04413) and one international coral standard (RKM-4) have been determined by using thcrmal ionization mass spcctrometry (TIMS) method. The values of (234U/238U)act, (230Th/234U)act and age are all consistent in error range with thc stantlard values obtained by using α spectrometry.

The formation of the Moon remains obscure after *400 years since Galileo saw that the Moon was mountainous in 1609. The current hypothesis is that the Moon formed through a low-angle collision between the Earth and Mar-size impactor,which is knownas theGiant Impactmodel (e.g.Benz et al. 1989). The giant impact should be sufficiently energetic to vaporize much of the material that went to make up the Moon. This explains the depletion of volatile elements in the Moon. According to this scenario, the Moon should contain a significant amount of material from the impactor. This is now challenged by geochemists (e.g. Stevenson and Halliday 2014; Asphaug 2014). As pointed out by Taylor, it is very likely that the possibleMoon-forming impactors possess isotopic ratios that differ from those of Earth (Taylor 2016). Isotopic analysis of lunar samples, however, has revealed little trace of material other than that resembling the Earth, i.e., the isotope ratios for the non-volatile elements in the Moon have nearly identical values to those on the Earth. In this volume, Taylor proposed two alternative models. The first model is that the Moon may have been formed through a process similar to the formation of tektites, which excavates part of the terrestrial mantle (low in metallic iron), depletes the proto-lunar material in volatiles, melts much of the material and left little or no trace of itself (Taylor 2016). This model, however, still needs to explain why the impactor was not seen in the Moon. Another model is Cometary Impact about 100 Ma after the formation of the Earth. Given that the composition of the Moon looks like massive distal ejecta from the terrestrial mantle without definitive evidence of the impacting body, it is proposed that massive impacts on the terrestrial mantle by icy comets, which provided energy to melt most of the Moon, deplete the volatile elements, and leave little or any trace of the impactor (Taylor 2016). The Earth is a rocky planet, which requires additional water possibly from icy comets (Albarede 2009). This stimulating model explains both the formation of the Moon and the possession of water in the Earth. The challenges of this model are: first, Hf-W isotopes suggest that the Moon-forming Impact occurred at *30 Ma after the formation of the Earth (Yin et al. 2002), whereas it has been proposed that the addition of water occurred 70 Ma later (Albarede 2009). Moreover, it may also needs additional mechanism to explain the dry nature of the Moon.