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Sedimentary carbonates are known to be carried into the deep mantle by subducted slabs, and studies on mantle‐derived magmas have attempted to trace the recycled carbonate in their mantle source. However, the final depth of storage of recycled carbonate and the role of recycled carbonate in the partial melting of mantle remain controversial. Peralkaline‐carbonatite suites are considered to have been derived from a carbonated mantle source and are windows to evaluate carbon in the mantle. In this study, we report the Zn isotopic compositions of a peralkaline‐carbonatite suite from the Tarim Large Igneous Province (Tarim LIP). The peralkaline‐carbonatite suite has heavier δ66Zn than normal mantle with δ66Zn of 0.34–0.40 ‰ for nephelinite, 0.35–0.47 ‰ for aillikite, 0.51–0.55 ‰ for nepheline syenite, 0.58–0.67 ‰ for calciocarbonatite and 0.38–0.56 ‰ for magnesiocarbonatite. The heavy Zn isotopic compositions of the peralkaline‐carbonatite suite in the Wajilitag complex suggest the incorporation of recycled carbonate‐bearing materials into the deep mantle. We infer that the calciocarbonatite was produced by the initial partial melting of subducted MgSiO3/MgO + C‐bearing carbonated eclogite, whereas the magnesiocarbonatite, aillikite, and nephelinite are considered as reacted melts between carbonated eclogite‐derived melts and peridotite. The heavy Zn isotopic compositions of the nepheline syenite are attributed to fractional crystallization from nephelinite magma in the magma reservoir. Our study highlights the incorporation of carbonated eclogite as an important agent of recycled carbon in the deep mantle and interactions between carbonated eclogite‐derived melts and peridotite lead to the complex lithological heterogeneities in the peralkaline‐carbonatite suite in Tarim LIP. Key Points: Zn isotopes of the peralkaline‐carbonatite suite in TLIP show that the subducted carbon is recycled in the form of MgSiO3/MgO + CThe carbonated eclogite‐derived melt‐peridotite reaction as the key for the formation of aillikite and nephelinite in TLIPThe incorporation of carbonated eclogite as an important source of recycled carbon in the deep mantle [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzothiophenes (PCDTs) are sulfur analogues of polychlorinated dibenzofurans with prevalent occurrence in aquatic environments and potential ecological risks. However, data on the behavior and toxicity of PCDTs in aquatic organisms remain scarce. In the present study, the bioaccumulation, metabolism, and oxidative damage of 4‐mono‐chlorinated dibenzothiophene (4‐mono‐CDT) in freshwater mussel (Hyriopsis cumingii) were investigated after exposure to 4‐mono‐CDT in semistatic water. The uptake rates, depuration rates, half‐lives, and bioconcentration factors of 4‐mono‐CDT in hepatopancreas, gill, and muscle tissues ranged from 0.492 to 1.652 L d−1 g−1 dry weight, from 0.117 to 0.308 d−1, from 2.250 to 5.924 d, and from 2.903 to 8.045 × 103 L kg−1 dry weight, respectively. A dechlorinated metabolite (dibenzothiophene) was detected in hepatopancreas tissue, indicating that dechlorination was the main metabolic pathway of 4‐mono‐CDT. As the exposure time increased, the activities of superoxide dismutase, catalase, and glutathione peroxidase were induced or inhibited in the different experimental groups. The malondialdehyde content increased with increasing 4‐mono‐CDT dose and exposure time. A higher concentration of 4‐mono‐CDT corresponded to a greater integrated biomarker response in each tissue and greater oxidative damage. The antioxidant enzymes in hepatopancreas were more sensitive to 4‐mono‐CDT than those in gill. The results provide useful information on the behavior and ecotoxicity of PCDTs in freshwater mussels. Environ Toxicol Chem 2021;40:1873–1882. © 2021 SETAC [ABSTRACT FROM AUTHOR]

Porphyry Cu–Au ores areamong the important types of porphyry deposits. Some of these are enriched in Pd and Pt, which in some cases have economic potential for PGE (platinum group element) recovery. The behaviour of PGE and S‐saturation in mafic intrusions associated with porphyry deposits are, however, poorly constrained. Here we investigate the PGE concentrations of gabbroic intrusions from Akcha, Beleuti, and Kalmakyr in the Almalyk porphyry Cu–Au ore field in Uzbekistan through Ni–S analyses employing fire assay‐isotope dilution method. The results reveal extremely high Pd/Ir ratio and a negative Ru anomaly for the Beleuti and Akcha gabbro which we attribute to fractional crystallization of olivine and Ru–Os–Ir alloys. The extremely high Cu/Pd ratio (2.56 × 105–2.98 × 106) and depleted PGE contents of the Kalmakyr gabbro possibly represent immiscible separation of sulphide. During the emplacement of the parental magma of Kalmakyr gabbro, crustal contamination might have resulted in S‐saturation and sulphide segregation. Sulphide‐bearing crust was remobilized during the increasing maturity of the island and long‐lived arc magmatism, which released the sulphide into the hydrothermal system of the porphyry deposit. We propose that this process favoured the enrichment of Pt–Pd and sulphide in the Kalmakyr porphyry Cu–Au deposit. [ABSTRACT FROM AUTHOR]

The bimodal intermediate‐felsic suites are rare, and their petrogenesis remains unsolved. Here, we report a bimodal intermediate‐felsic magmatic suite from East Junggar (NW China) composed of rhyolites, basaltic andesites, and andesites. The basaltic andesites and andesites are porphyritic with phenocrysts predominantly of plagioclase. The rhyolites are porphyritic with phenocrysts of alkali‐feldspar, quartz, and minor plagioclase. LA–ICP–MS zircon U–Pb dating yielded an age of 284 ± 2 Ma for rhyolites. The basaltic andesites and andesites show SiO2 ranging from 54.67 to 58.26 wt%, and exhibit moderate TiO2 (1.45–1.77 wt%), and K2O (1.59–2.07 wt%) with low MgO (1.51–2.25 wt%). They display enrichment in HFSE and LILE together with negative Th, Nb, Ta, Ti anomalies, and exhibit low 87Sr/86Sr(t) ratios (0.7040–0.7046), high positive εNd(t) values (+5.82 to +6.16) and young TDM ages (<0.6 Ga). The rhyolites exhibit highSiO2(>75 wt%), negative Nb, Ta anomalies and significant depletion in Ba, Eu, Sr, Ti, and P. They also show high εNd(t) values (+5.51 to +7.08) and young TDM ages (<0.6 Ga), which are close to those of the intermediate rocks. Except for elements dominantly controlled by fractional crystallization, the other trace elements of the bimodal suite display similar patterns. Based on these characteristics, the MELTS simulation further suggests that the felsic rocks were possibly evolved from the intermediate magmas through fractional crystallization of feldspar, clinopyroxene, iron‐titanium oxide, and apatite. In contrast, the magmas parental to basaltic andesites were derived from the remelting of basaltic rocks underplated beneath the lower crust. The petrogenesis of this bimodal suite also provides new insights into Permian crustal reworking in the East Junggar, and suggest that the Junggar Ocean was closed prior to the Early Permian. [ABSTRACT FROM AUTHOR]

The article talks about the orogenic event of North Qinling Terrain, understanding the evolution of tectonic plates before the amalgamation of North China Block and South China Block along the Mianxian-Lueyang suture zone. It talks about the spread of the oceanic crust, subduction, collision that leads to the closure of Shang-Dan Paleotethys, different types of granites, leucogranite and felsic intrusion linked to continental crust.

ABSTRACT A novel model based on a radial basis function neural network (RBF NN), chaos theory, self-adaptive particle swarm optimization (PSO), and a clustering method is proposed to predict the gas solubility in polymers; this model is hereafter called CSPSO-C RBF NN. To develop the CSPSO-C RBF NN, the conventional PSO was modified with chaos theory and a self-adaptive inertia weight factor to overcome its premature convergence problem. The classical k-means clustering method was used to tune the hidden centers and radial basis function spreads, and the modified PSO algorithm was used to optimize the RBF NN connection weights. Then, the CSPSO-C RBF NN was used to investigate the solubility of N2 in polystyrene (PS) and CO2 in PS, polypropylene, poly(butylene succinate), and poly(butylene succinate- co-adipate). The results obtained in this study indicate that the CSPSO-C RBF NN was an effective method for predicting the gas solubility in polymers. In addition, compared with conventional RBF NN and PSO neural network, the CSPSO-C RBF NN showed better performance. The values of the average relative deviation, squared correlation coefficient, and standard deviation were 0.1282, 0.9970, and 0.0115, respectively. The statistical data demonstrated that the CSPSO-C RBF NN had excellent prediction capabilities with a high accuracy and a good correlation between the predicted values and the experimental data. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3825-3832, 2013 [ABSTRACT FROM AUTHOR]

To replace costly and time-consuming experimentation in laboratory, a novel solubility prediction model based on chaos theory, self-adaptive particle swarm optimization (PSO), fuzzy c-means clustering method, and radial basis function artificial neural network (RBF ANN) is proposed to predict CO2 solubility in polymers, hereafter called CSPSO-FC RBF ANN. The premature convergence problem is overcome by modifying the conventional PSO using chaos theory and self-adaptive inertia weight factor. Fuzzy c-means clustering method is used to tune the hidden centers and radial basis function spreads. The modified PSO algorithm is employed to optimize the RBF ANN connection weights. Then, the proposed CSPSO-FC RBF ANN is used to investigate solubility of CO2 in polystyrene (PS), polypropylene (PP), poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA), respectively. Results indicate that CSPSO-FC RBF ANN is an effective method for gas solubility in polymers. In addition, compared with conventional RBF ANN and PSO ANN, CSPSO-FC RBF ANN shows better performance. The values of average relative deviation (ARD), squared correlation coefficient ( R2) and standard deviation (SD) are 0.1071, 0.9973 and 0.0108, respectively. Statistical data demonstrate that CSPSO-FC RBF ANN has excellent prediction capability and high-accuracy, and the correlation between prediction values and experimental data is good. [ABSTRACT FROM AUTHOR]

A four-layer fuzzy neural network (FNN) model combining particle swarm optimization (PSO) algorithm and clustering method is proposed to predict the solubility of gases in polymers, hereafter called the CPSO-FNN, which combined fuzzy theory's better adaptive ability, neural network's capability of nonlinear and PSO algorithm's global search ability. In this article, the CPSO-FNN model has been employed to investigate solubility of CO2 in polystyrene, N2 in polystyrene, and CO2 in polypropylene, respectively. Results obtained in this work indicate that the proposed CPSO-FNN is an effective method for the prediction of gases solubility in polymers. Meanwhile, compared with traditional FNN, this method shows a better performance on predicting gases solubility in polymers. The values of average relative deviation, squared correlation coefficient ( R2) and standard deviation are 0.135, 0.9936, and 0.0302, respectively. The statistical data demonstrate that the CPSO-FNN has an outstanding prediction accuracy and an excellent correlation between prediction values and experimental data. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on early paleozoic magmatism and crustal evolution in the North Qinling Orogen. Topics include multi-phase tectonic-magmatic events found in North Qinling orogenic belt; chronlogical and chemical evidence for the evolution of the basement and tectonic provenance of the Qinling orogenic belt; and a comparison with the magmatism and crustal evolution of the adjacent terrains.

To clarify the infection approach of Diplodia sapinea, a pathogen that causes tip blight of Pinus tabulaeformis, the infection process of the pathogen in needles was observed using scanning electron microscopy (SEM). In addition, the disease incidence on branches damaged by Aphrophora flavipes (Hemiptera: Cercopidae) and Dioryctria splendidella (Lepidoptera: Pyralidae) in the forest was also investigated. Then, branches and needles of P. tabulaeformis were inoculated using the D. sapinea spore suspension under indoor and field conditions. The results showed that the damage caused by A. flavipes could aggravate the occurrence of tip blight of P. tabulaeformis to some extent. Moreover, the pathogen could also penetrate 1‐, 2‐ and 3‐year‐old pine needles through stomata in the field. The pathogen infected the 1‐year‐old branches first and then gradually spread to 2‐ and 3‐year‐old branches. [ABSTRACT FROM AUTHOR]