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The mineral zircon has a robust crystal structure, preserving a wealth of geological information through deep time. Traditionally, trace elements in magmatic and hydrothermal zircon have been employed to distinguish between different primary igneous or metallogenic growth fluids. However, classical approaches based on mineral geochemistry are not only time consuming but often ambiguous due to apparent compositional overlap for different growth environments. Here, we report a compilation of 11 004 zircon trace element measurements from 280 published articles, 7173 from crystals in igneous rocks, and 3831 from ore deposits. Geochemical variables include Hf, Th, U, Y, Ti, Nb, Ta, and the REEs. Igneous rock types include kimberlite, carbonatite, gabbro, basalt, andesite, diorite, granodiorite, dacite, granite, rhyolite, and pegmatite. Ore types include porphyry Cu-Au-Mo, skarntype polymetallic, intrusion-related Au, skarn-type Fe-Cu, and Nb-Ta deposits. We develop Decision Tree, XGBoost, and Random Forest algorithms with this zircon geochemical information to predict lithology or deposit type. The F1-score indicates that the Random Forest algorithm has the best predictive performance for the classification of both lithology and deposit type. The eight most important zircon elements from the igneous rock (Hf, Nb, Ta, Th, U, Eu, Ti, Lu) and ore deposit (Y, Eu, Hf, U, Ce, Ti, Th, Lu) classification models, yielded reliable F1-scores of 0.919 and 0.891, respectively. We present a web page portal (http://60.205.170.161:8001/) for the classifier and employ it to a case study of Archean igneous rocks in Western Australia and ore deposits in Southwest China. The machine learning classifier successfully determines the known primary lithology of the samples, demonstrating significant promise as a classification tool where host rock and ore deposit types are unknown. [ABSTRACT FROM AUTHOR]

Modified polyglycolic acid (PGA) was prepared by melt blending and reactive extrusion. The effects of chain extenders, crosslinking agents and lubricants on melt fluidity, dynamic rheological properties, thermal stability, and crystallization properties of modified samples were studied. The results show that the melt strength of samples are significantly improved by using ADR chain extender and BIBP crosslinking agent simultaneously, the melt mass flow rate is decreased by 73.6% compared to pure PGA. The thermal stability of modified samples is also improved, with increasing the 5% thermal decomposition temperature by 7 °C. With the addition of chain extender and crosslinking agent, the degree of crystallinity of PGA samples are decreased, the number of crystal nuclei are decreased, and the spherulite size are increased. The degree of cross-linking of the sapmles with adding chain extender and crosslinking agent at the same time is increased, resulting in imperfect crystallization and the formation of irregular crystals. Molecular motion are promoted by lubricants, and the crystallization temperature of PGA sample is decreased from 179.3 °C without addition to 173.9 °C after addition. [ABSTRACT FROM AUTHOR]

In order to improve the stability of polypropylene in the extrusion process, the modified polypropylene was prepared by melt extrusion technology, and the effects of antioxidant type, antioxidant ratio and hydrotalcite type on the processing stability of polypropylene were studied. The results show that the combination of hydroxylamine antioxidant and pentaerythritol phosphite antioxidant improve the processing stability of polypropylene, and the a value (red and green) is less than 0 and b value (yellow and blue) is less than 1.5 in multiple extrusion processing, and the melt flow rate increment is less than 5 g/10 min. Hydrotalcite with a large particle size and good dispersion is beneficial to improve the processing stability of polypropylene. The combination of hydroxylamine antioxidants, pentaerythritol phosphite antioxidants, and hydrotalcite with large particle size dispersion is conducive to improving the processing stability of polypropylene. [ABSTRACT FROM AUTHOR]

Background and Aim: This study aimed to clarify health‐related quality of life (HRQoL) of patients with colorectal precancer and colorectal cancer (CRC) in China and to better understand related utility scores. Methods: A hospital‐based cross‐sectional survey was conducted in precancer and CRC patients from 2012 to 2014, covering 12 provinces in China. HRQoL was assessed with EuroQol 5‐Dimensions 3‐Levels. Utility scores were derived using Chinese value set. A multivariate regression model was established to explore potential predictors of utility scores. Results: A total of 376 precancer (mean age 58.7 years, 61.2% men) and 2470 CRC patients (mean age 58.6 years, 57.6% men) were included. In five dimensions, there was a certain percentage of problem reported among precancer (range: 12.0% to 36.7%) and CRC (range: 32.4% to 50.3%) patients, with pain/discomfort being the most serious dimension. Utility scores of precancer and CRC patients were 0.870 (95% confidence interval [CI], 0.855–0.886) and 0.751 (95% CI, 0.742–0.759), both of which were lower than those of general Chinese population (0.960 [95% CI, 0.960–0.960]). Utilities for patients at stage I to stage IV were 0.742 (95% CI, 0.715–0.769), 0.722 (95% CI, 0.705–0.740), 0.756 (95% CI, 0.741–0.772), and 0.745 (95% CI, 0.742–0.767), respectively. Multivariate analysis showed that therapeutic regimen, time point of the interview, education, occupation, annual household income, and geographic region were associated with utilities of CRC patients. Conclusion: Health‐related quality of life of both precancer and CRC patients in China declined considerably. Utility scores differed by sociodemographic and clinical characteristics, and findings of these utilities may facilitate implementation of further cost–utility evaluations. [ABSTRACT FROM AUTHOR]