Efficient linking of two epoxides using potassium thioacetate in water and its use in polymerization

2022 ◽  
Author(s):  
Takanori Kishida ◽  
Tomio Shimada ◽  
Kazunori Sugiyasu
Keyword(s):  
Stoichiometric Ratios

Two epoxides can be efficiently linked using potassium thioacetate in water even at their imbalanced stoichiometric ratios.

scholarly journals Nutrient and Stoichiometric Characteristics of Aggregates in a Sloping Farmland Area under Different Tillage Practices

2021 ◽  
Vol 13 (2) ◽  
pp. 890
Author(s):  
Jie Zhang ◽  
Yaojun Liu ◽  
Taihui Zheng ◽  
Xiaomin Zhao ◽  
Hongguang Liu ◽  
...  
Keyword(s):  
Organic Matter ◽  
Size Distribution ◽  
Soil Aggregates ◽  
Soil Aggregate ◽  
Elemental Content ◽  
Stoichiometric Ratio ◽  
Longitudinal Ridge ◽  
Stoichiometric Ratios ◽  
Sloping Farmland ◽  
Ridge Tillage

Sloping farmland is prevalent in hilly red soil areas of South China. Improper tillage patterns induce decreased soil organic matter, soil aggregate breakdown, and nutrient imbalance, thereby restricting crop production. However, the stoichiometric characteristics could reflect the nutrient availability which was mostly studied on bulk soil. The stoichiometric characteristics of soil aggregates with multiple functions in farmlands has rarely been studied. The study was to reveal the impact of tillage patterns on the size distribution, nutrient levels, and stoichiometric ratios of soil aggregates after 20 years’ cultivation. Soil samples of 0–20 cm and 20–40 cm from five tillage patterns, bare-land control (BL), longitudinal-ridge tillage (LR), conventional tillage + straw mulching (CS), cross-ridge tillage (CR), and longitudinal-ridge tillage + hedgerows (LH) were collected. The elemental content (C, N and P) and soil aggregate size distribution were determined, and the stoichiometric ratios were subsequently calculated. Through our analysis and study, it was found that the nutrient content of >2 mm soil aggregates in all plots was the highest. In the hedgerow plots, >2 mm water-stable soil aggregate content was increased. Therefore, LH plots have the highest content of organic matter and nutrients. After 20 years of cultivation, stoichiometric ratio of each plot showed different changes on soil aggregates at different levels. the C:N, C:P, and N:P ratios are lower than the national average of cultivated land. Among of them, the stoichiometric ratio in the LH plot is closer to the mean and showed better water-stable aggregate enhancement. Therefore, longitudinal-ridge tillage + hedgerows can be recommended as a cultivation measure. This study provides a reference for determining appropriate tillage measures, balancing nutrient ratios, and implementing rational fertilization.

scholarly journals Carbide Synthesis from Graphite/molybdenum Powder Mixtures at Sub-Stoichiometric Ratios under Solar Radiation Heating to 1900°C

2008 ◽  
Vol 49 (11) ◽  
pp. 2673-2678 ◽  
Author(s):  
Bernard Granier ◽  
Jean-Marie Badie ◽  
Fernando Almeida Costa Oliveira ◽  
Teresa Magalhães ◽  
Nobumitsu Shohoji ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Molybdenum Powder ◽  
Radiation Heating ◽  
Powder Mixtures ◽  
Stoichiometric Ratios

scholarly journals How Elemental Stoichiometric Ratios in Microorganisms Respond to Thinning Management in Larix principis-rupprechtti Mayr. Plantations of the Warm Temperate Zone in China

Forests ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 684
Author(s):  
Mengke Cai ◽  
Shiping Xing ◽  
Xiaoqing Cheng ◽  
Li Liu ◽  
Xinhao Peng ◽  
...  
Keyword(s):  
Microbial Biomass ◽  
Soil Temperature ◽  
Microbial Communities ◽  
Microbial Biomass Carbon ◽  
Gram Negative Bacteria ◽  
Medium Density ◽  
Biomass Carbon ◽  
Gram Negative ◽  
Gram Positive Bacteria ◽  
Stoichiometric Ratios

The stoichiometric ratios of elements in microorganisms play an important role in biogeochemical cycling and evaluating the nutritional limits of microbial growth, but the effects of thinning treatment on the stoichiometric ratio of carbon, nitrogen, and phosphorus in microorganisms remain unclear. We conducted research in a Larix principis-rupprechtti Mayr. plantation to determine the main factors driving microbial carbon (C): nitrogen (N): phosphorus (P) stoichiometry following thinning and the underlying mechanisms of these effects. The plantation study varied in thinning intensity from 0% tree removal (control), 15% tree reduction (high density plantation, HDP), 35% tree reduction (medium density plantation, MDP), and 50% tree reduction (low density plantation, LDP). Our results indicated that medium density plantation significantly increased litter layer biomass, soil temperature, and other soil properties (e.g., soil moisture and nutrient contents). Understory vegetation diversity (i.e., shrub layer and herb layer) was highest in the medium density plantation. Meanwhile, thinning had a great influence on the biomass of microbial communities. For example, the concentration of phospholipid fatty acids (PLFA) for bacteria and fungi in the medium density plantation (MDP) was significantly higher than in other thinning treatments. Combining Pearson correlation analysis, regression modeling, and stepwise regression demonstrated that the alteration of the microbial biomass carbon: nitrogen was primarily related to gram-positive bacteria, gram-negative bacteria, soil temperature, and soil available phosphorus. Variation in bacteria, actinomycetes, gram-positive bacteria, gram–negative bacteria, and soil total phosphorus was primarily associated with shifts in microbial biomass carbon: phosphorus. Moreover, changes in microbial biomass nitrogen: phosphorus were regulated by actinomycetes, gram-negative bacteria, and soil temperature. In conclusion, our research indicates that the stoichiometric ratios of elements in microorganisms could be influenced by thinning management, and emphasizes the importance of soil factors and microbial communities in driving soil microbial stoichiometry.

HALIDE ALKOXIDES OF SAMARIUM: III. REACTIONS OF SAMARIUM ALKOXIDES WITH ACETYL CHLORIDE AND ACETYL BROMIDE

1966 ◽  
Vol 44 (18) ◽  
pp. 2131-2137 ◽  
Author(s):  
B. S. Sankhla ◽  
R. N. Kapoor
Keyword(s):  
Hydrogen Chloride ◽  
Acetyl Chloride ◽  
Acetyl Bromide ◽  
Acyl Halide ◽  
Exothermic Reactions ◽  
Stoichiometric Ratios ◽  
Derivatives Of ◽  
Acyl Halides

The reactions of samarium n-butoxide, isopropoxide, and tert-butoxide with acyl halides in different stoichiometric ratios have been studied and products of the type Sm(OR)2X, Sm(OR)X2•0.5CH3COOR and SmX3•CH3COOR (where R = C4H9n, C3H7i, or C4H9t and X = Cl or Br) have been isolated in quantitative yields. All these reactions are exothermic and the amount of heat liberated also increases with the increase in the concentration of acyl halide. These reactions have been further confirmed by the reactions with anhydrous samarium trichloride and the corresponding esters, which are also exothermic reactions. Attempts to sublime the dialkoxy monohalide derivatives of samarium were unsuccessful. The reaction of a dry current of hydrogen chloride gas on samarium isopropoxide has also been investigated.

Syntheses and Molecular Structures of Heteroleptic and Homoleptic Antimony(III) Tetrafluorophenylethylenediamidate Complexes

2020 ◽  
Vol 73 (6) ◽  
pp. 504
Author(s):  
Areej K. Aldabbagh ◽  
Peter C. Junk ◽  
Jun Wang
Keyword(s):  
Solid State ◽  
Alternative Pathway ◽  
Molecular Structures ◽  
Direct Reaction ◽  
Pendant Arm ◽  
Metathesis Reactions ◽  
Stoichiometric Ratios ◽  
Interesting Alternative

A series of hetero- and homoleptic organoamidoantimony(iii) complexes of the type [SbLMe3−nCln] (n=2, 1, 0) (HLMe=p-HC6F4NH(CH2)2NMe2) incorporating a bulky amido fluorinated ligand tethered with an amino pendant arm, have been successfully synthesised and fully characterised as monomers in the solid state. [Sb(p-HC6F4NC2H4NMe2)Cl2] (1), [Sb(p-HC6F4NC2H4NMe2)2Cl] (2), and [Sb(p-HC6F4NC2H4NMe2)3] (3) were isolated by metathesis reactions involving different stoichiometric ratios between SbCl3 and Li(p-HC6F4N(CH2)2NMe2) (LiLMe) in non-coordinating solvents, while [Sb(p-HC6F4NC2H4NMe2)Cl2] (1) was also synthesised by the direct reaction between SbCl3 and HLMe in THF providing an interesting alternative pathway to access these types of compounds.

scholarly journals Spatiotemporal Variations in Seston C:N:P Stoichiometry in a Large Eutrophic Floodplain Lake (Lake Taihu): Do the Sources of Seston Explain Stoichiometric Flexibility?

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 36
Author(s):  
Jian Cai ◽  
Chengrong Bai ◽  
Xiangming Tang ◽  
Jiangyu Dai ◽  
Xingyu Jiang ◽  
...  
Keyword(s):  
Lake Taihu ◽  
Freshwater Ecosystems ◽  
Floodplain Lakes ◽  
Agricultural Watershed ◽  
Particulate Phosphorus ◽  
Floodplain Lake ◽  
Spatiotemporal Variations ◽  
Eutrophic Lakes ◽  
C:N:P Stoichiometry ◽  
Stoichiometric Ratios

Although sources of seston are much more complicated in lakes compared to oceans, the influences of different sources on the spatiotemporal variations in seston stoichiometry are still underexplored, especially in large eutrophic floodplain lakes. Here, we investigated seston stoichiometric ratios across a typical large eutrophic floodplain lake (Lake Taihu, East China) over one year. In addition, we used the n-alkane proxies to examine the influence of the seston source on seston stoichiometry variation. Throughout the study, the average value of the C:N:P ratio of 143:19:1 across Lake Taihu was close to the canonical lake’s ratios (166:20:1). Similar to other eutrophic lakes, seston C:N ratios varied the least across all environments, but C:P and N:P ratios varied widely and showed a strong decreasing trend in ratios of N:P and C:P from growing season to senescence season. This seasonal change was mainly associated with the decreasing contribution from algal-derived materials in seston pools because the non-algal dominated seston exhibited significantly lower ratios than algal-dominated seston. Furthermore, the spatial heterogeneity of stoichiometric ratios was also related to the seston source. During the senescence season, the terrestrial-dominated seston from agricultural watershed exhibited the lowest ratios in estuary sites compared with other areas. Statistically, the predictive power of environmental variables on stoichiometric ratios was strongly improved by adding n-alkanes proxies. Apart from source indicators, particulate phosphorus (PP) contents also partly explained the spatiotemporal variations in stoichiometric ratios. This study, thus, highlights the utility of multiple-combined n-alkane proxies in addition to simple C:N ratios to get more robust source information, which is essential for interpreting the spatiotemporal variations in seston stoichiometric ratios among eutrophic floodplain lakes and other freshwater ecosystems.

The effect of vegetation cover on ecological stoichiometric ratios of soil carbon, nitrogen and phosphorus: A case study of the Dunhuang Yangguan wetland

2019 ◽  
Vol 39 (2) ◽  
Author(s):  
张剑 ZHANG Jian ◽  
宿力 SU Li ◽  
王利平 WANG Liping ◽  
包雅兰 BAO Yalan ◽  
陆静雯 LU Jingwen ◽  
...  
Keyword(s):  
Soil Carbon ◽  
Vegetation Cover ◽  
Nitrogen And Phosphorus ◽  
Stoichiometric Ratios

ARGET ATRP of Methacrylates and Acrylates with Stoichiometric Ratios of Ligand to Copper

2008 ◽  
Vol 209 (17) ◽  
pp. 1797-1805 ◽  
Author(s):  
Nicky Chan ◽  
Michael F. Cunningham ◽  
Robin A. Hutchinson
Keyword(s):  
Arget Atrp ◽  
Stoichiometric Ratios
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