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Clarify the value of ceramic containers used in tea packaging from the development process, study the impact of contemporary consumer culture, industrialization and globalization on ceramic tea packaging containers, discuss the orientation and development strategy of contemporary ceramic containers design applied to tea packaging.

The R programming language that provides a variety of statistical calculation functions is considered to be one of the programming languages most suitable for artificial intelligence.The correctness of the language implementation is a prerequisite for the correctness of the programs developed with such a language.However,there are inevitably many defects in the R programming language.This paper conducts an empirical study on defects in the R programming language and its core packages.By analyzing 7020 issues,we find that:1) Among all the 35 versions involved in these defects,there are the most defects in R 3.1.2,R 3.0.2 and R 3.5.0,and these defects are primarily distributed in a few components such as Documentation,Graphics,Language.2) The components with higher overall defect priority include Startup,Installation and Analyses,and the components with higher overall defect severity include I/O,Installation and Accuracy.There is a significant intermediate correlation between the priority and severity of the defects.3) About 78% of defects could be repaired within one year.4) Semantic faults are the most frequent root cause of defects,in which the “missing feature” and “processing” are more than others.These findings reveal some laws of defects in the R programming language and its core packages.It can assist developers of the R programming language in improving their development quality,assist maintainers of the R programming language in detecting and repairing defects more effectively,and suggest users of the R programming language evade potential risks.

1,3,5-tris（3,3,3-trifluoropyl）-1,3,5-trimethylcyclotrisiloxane （D3F） and hexamethylcyclotrisiloxane were used as raw materials to synthesize fluorosilicone copolymer with high molecular weight. The effects of reaction time and reaction temperature on molecular weight of the products and monomer ratio on chain segment content of the copolymers were studied. The structure of the copolymer was characterized by infrared spectroscopy and nuclear magnetic resonance spectroscopy, and its molecular weight was determined by Ubbelohde viscometer. The results showed that the proportion of chain segment content in fluorosilicone rubber was closer to that of feed when D3F amount was high. With increase of reaction temperature and time, molecular weight of the fluorosilicone copolymer first increased and then decreased. Molecular weight of fluorosilicone copolymer could be effectively increased by stopping heating at an approp-riate node in the reaction process. When the reaction temperature was 90 ℃, reaction time was 10 min and mole fraction of D3F was 80%, molecular weight of fluorosilicone copolymer reached the maximum, and the viscosity average molecular weight was 8.2×105.

It is naturally common that different proportions of ramets in a clone lose rooting conditions due to habitat stress or obstacles, which potentially affects the overall growth of the clonal plant to different extents. However, so far, little attention has been paid to such phenomena and much less to the underlying ecological mechanisms. Taking Zoysia japonica as material, through an experiment with two nutrition levels in the habitats and five rooting ramet proportions in the clones, the impacts of proportions of rooting ramets in the clone on the overall growth were tested and the ecological mechanisms were analyzed. The results showed that there was no significant difference in the total clonal biomasses among the clones with five rooting ramet proportions under high and low nutrition levels, except for that with 0% rooting ramet proportion. Under both high and low nutrition levels, the lower rooting ramet proportions (0% and 25%) in the clones significantly decreased the number of the so‐called A‐ and B‐ramets, root biomass, stolon length per unit biomass, and root–shoot ratio, but significantly increased the stolon biomass of the clones. Stolon elongation was promoted under high nutrient level, and biomass allocations to stolons and roots increased under low nutrition levels. A‐ramet biomasses accounted for about 50% and 30% of the total biomasses of the whole clone under high and low nutrition levels, respectively. These results might be reasonably explained in terms of clonal integration, compensatory growth, division of labor, and bet‐hedging strategy. [ABSTRACT FROM AUTHOR]