A feasible method to determine the critical DS for modified polysaccharide derivatives' gelation by gel point, tg

One facile and efficient strategy for the hydrosilylation of steric 1,1-disubstituted terminal alkenes is demonstrated. Investigations on substrate scope and control experiments revealed the necessity of thioether in promoting this process under a simple iridium catalysis system. This convenient and feasible method is expected to be useful in the synthesis of sulfur-containing organosilicon polymers with different side-chains.

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A feasible method for measuring photosynthesis in vitro for major tree species in northeastern China

Chinese Journal of Plant Ecology ◽

10.3724/sp.j.1258.2011.00452 ◽

2011 ◽

Vol 35 (4) ◽

pp. 452-462 ◽

Cited By ~ 3

Author(s):

Yan TANG ◽

Chuan-Kuan WANG

Keyword(s):

Tree Species ◽

Northeastern China ◽

Feasible Method

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Evaluating ozone dose for AOC removal in two-step GAC filters

Water Science & Technology ◽

10.2166/wst.1998.0347 ◽

1998 ◽

Vol 37 (9) ◽

pp. 113-120 ◽

Cited By ~ 6

Author(s):

R. Vahala ◽

T. Ala-Peijari ◽

J. Rintala ◽

R. Laukkanen

Keyword(s):

Activated Carbon ◽

Organic Carbon ◽

Second Step ◽

Humic Lake ◽

Short Term ◽

Feasible Method ◽

Assimilable Organic Carbon ◽

Water Treatment Plants ◽

Ozone Dose ◽

Ozonated Water

Upgrading an existing post-ozonation plant with two-step granular activated carbon (GAC) filtration for assimilable organic carbon (AOC) removal was studied. The effects of ozone dose on AOC formation and its removal in the subsequent two-step GAC filtration was studied using chemically pretreated 2 to 14° C humic lake water. Two parallel pilot-plant trains with different ozone doses (0 to 1.2 mgO3/mgTOC) and a short-term ozonation study were performed. The optimum ozone dose for maximum AOC formation was 0.4–0.5 mgO3/mgTOC. The AOC-P17 of ozonated water was three-fold higher and AOC-NOX over ten-fold higher than in non-ozonated water, while the following biofiltration (first step) removed 51% and 72% of AOC-P17 and AOC-NOX, respectively. The adsorber (second step) contributed to less than 10% of the overall AOC reduction. It appeared that biofiltration is a feasible method in upgrading water treatment plants for AOC removal even when treating cold humic waters, while the subsequent adsorber seems to have less significance for AOC removal.

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Improved Processing and Properties for Polyphenylene Oxide Modified by Diallyl Orthophthalate Prepolymer

Polymers ◽

10.3390/polym11122016 ◽

2019 ◽

Vol 11 (12) ◽

pp. 2016

Author(s):

Honghua Wang ◽

Qilin Mei ◽

Yujie Ding ◽

Zhixiong Huang ◽

Minxian Shi

Keyword(s):

Differential Scanning Calorimetry ◽

Thermal Properties ◽

Phase Separation ◽

Dilution Effect ◽

Gradual Decrease ◽

Gel Point ◽

Dynamic Mode ◽

Curing Process ◽

Scanning Calorimetry ◽

Polyphenylene Oxide

Diallyl orthophthalate (DAOP) prepolymer was investigated as a reactive plasticizer to improve the processability of thermoplastics. The rheology of blends of DAOP prepolymer initiated by 2,3-dimethyl-2,3-diphenylbutane (DMDPB) and polyphenylene oxide (PPO) was monitored during the curing process, and their thermal properties and morphology in separated phases were also studied. Differential scanning calorimetry (DSC) results showed that the cure degree of the reactively plasticized DAOP prepolymer was reduced with increasing PPO due to the dilution effect. The increasing amount of the DAOP prepolymer led to a gradual decrease in the viscosity of the blends and the rheology behavior was consistent with the chemical gelation of DAOP prepolymer in blends. This indicated that the addition of the DAOP prepolymer effectively improved processability. The phase separation occurring during curing of the blend and the transition from the static to dynamic mode significantly influences the development of the morphology of the blend corresponding to limited evolution of the conversion around the gel point.

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