《尔雅·释草》名物词命名理据研究

《尔雅》作为一部以先秦以及秦汉时规范的标准语释古词语和方言词的专著,对当时自然界和人类社会所出现的各种各样的名物词进行了广泛的收集和整理,成为我国第一部分类字典。本论文选取《尔雅》的第十三篇《释草》篇中的名物词为研究对象,主要从主观、客观两个方面出发,对其命名理据进行研究考证。

Size-controlled preparation of hollow silica spheres and glyphosate release

Different-sized hollow SiO2 spheres of 249–1348 nm in diameter were successfully prepared by using Na2SiO3 as the precursor and using polystyrene and polystyrene-methyl acrylic acid latexes as the templates. The diameter and shell thickness of the hollow SiO2 spheres increase with increasing the latex template diameter at a given mass ratio of SiO2 to latex template. The diameter and shell thickness of the hollow SiO2 spheres also increase with increasing the mass ratios of SiO2 to latex template. The presence of carboxylic acid groups on the surfaces of polystyrene-methyl acrylic acid latex templates favors the formation of dense and uniform SiO2 shells. The hollow SiO2 sphere is constructed by mesoporous shell with large specific surface area. When glyphosate is used as a release model chemical, glyphosate release rate is tuned by varying the shell thickness.

Effect of Diluents on the Extraction of Oxalic Acid by Trialkylphosphine Oxide

In liquid-liquid solvent extraction processes, diluents have a strong influence on the extraction mechanism and efficiency. In this study, benzene, cyclohexane, trichloromethane, carbon tetrachloride, methyl isobutyl ketone (MIBK), butyl acetate, and 1-octanol were used as diluents in the extraction of oxalic acid by trialkylphos-phine oxide (TRPO). The effects of extractant concentration, initial concentration of oxalic acid and diluent type on the extraction equilibrium partition coefficient are analyzed. The sequence of the extraction ability by different diluents is MIBK > butyl acetate > cyclohexane=benzene > carbon tetrachloride > 1-octanol > trichloromethane. Extraction mechanism was analyzed and extraction model parameters were evaluated.

Biological Characteristies of Methane Emission of Oryzasativa，Panicumcrus－galliand Cyperusdif for misGrown on PaddySoil

Biological characteristics of methane emission were compared among Oryza sativa, Panicum crus-galli andCyperus difformis grown on paddy soil. The order of the amounts of methane emitted was P. crus-galli > O. sativa >C. difformis, with the former two 11 and 8 times as much as that of the latter, respectively. And it was just opposite tothat of the methane-forming activities of roots of the three plants. The diurnal changes of methane emission of thethree plants were relatively consistent with valleys during 11:00-14:00 and midnight and peaks during 8:00-11: 00,14:00- 20:00 and about 5:00 early morning. The methanogenic activites in rhizospheric soils were higher than those innonrhizospheric soils with P. crus-galli and O. sativa, but not with C. difformis. The pathways of methane release ofP. crus-galli and O . sativa were probably through the top gaps near the junctions of nodal plate and leaf sheath, how-ever in C. difformistopgaps from which methane could escape into atmosphere were not found.

Diurnal Variation of Soil CO2 Efflux and Its Optimal Measuring Time-window of Temperate Meadow Steppes in Western Songnen Plain, China

In order to study the diurnal variation of soil CO2 effiux from temperate meadow steppes in Northeast China, and determine the best time for observation, a field experiment was conducted with a LI-6400 soil CO2 flux system under five typical plant communi- ties （Suaeda glauca （Sg）, Chloris virgata （Cv）, Puecinellia distans （Pd）, Leymus chinensis （Lc） and Phragmites australis （Pa）） and an alkali-spot land （As） at the meadow steppe of western Songnen Plain. The results showed that the diurnal variation of soil CO2 effiux exhibited a single peak curve in the growing season. Diurnal maximum soil respiration （Rs） often appeared between 1 1：00 and 13：00, while the minimum occurred at 21：00-23：00 or before dawn. Air temperature near the soil surface （Ta） and soil temperature at 10 cm depth （Tlo） exerted dominant control on the diurnal variations of soil respiration. The time-windows 7：00-9：00 could be used as the optimal measuring time to represent the daily mean soil CO2 effiux at the Cv, Pd, Lc and Pa sites. The daily mean soil CO2 effiux was close to the soil COz effiux from 15：00 to 17：00 and the mean of 2 individual soil CO2 effiux from 15：00 to 19：00 at the As and Sg sites, respectively. During nocturnal hours, negative soil CO2 fluxes （CO2 downwards into the soil） were frequently observed at the As and Sg sites, the magnitude of the negative CO2 fluxes were 0.10-1.55 gmol/（m2.s） and 0.10-0.69 gmol/（m2.s）at the two sites. The results im- plied that alkaline soils could absorb CO2 under natural condition, which might have significant implications to the global carbon budget accounting.

Plant diversity promotes soil fungal pathogen richness under fertilization in an alpine meadow

Aims The effects of fertilization on fungal plant pathogens in agricultural soils have been studied extensively.However,we know little about how fertilization affects the relative abundance and richness of soil fungal plant pathogens in natural ecosystems,either through altering the soil properties or plant community composition.Methods Here,we used data from a 7-year nitrogen(N)addition experiment in an alpine meadow on the Qinghai-Tibetan Plateau to test how N addition affects the relative abundance and richness of soil fungal plant pathogens,as determined using Miseq sequencing of ITS1 gene biomarkers.We also evaluated the relative importance of changes in soil properties versus plant species diversity under N addition.Important Findings Using general linear model selection and a piecewise structural equation model,we found that N addition increased the relative abundance of soil fungal plant pathogens by significantly altering soil properties.However,higher host plant species richness led to higher soil fungal plant pathogen richness,even after excluding the effects of N addition.We conclude that the relative abundance and richness of soil fungal plant pathogens are regulated by different mechanisms in the alpine meadow.Continuous worldwide N inputs(through both fertilizer use and nitrogen deposition)not only cause species losses via altered plant species interactions,but also produce changes in soil properties that result in more abundant soil fungal plant pathogens.This increase in pathogen relative abundance may seriously threaten ecosystem health,thus interrupting important ecosystem functions and services.