Moisture content of the melt as a factor in the efficiency of orthophosphoric acid as molecular-weight regulator for polycaproamide

1977 ◽  
Vol 8 (6) ◽  
pp. 602-607
Author(s):  
L. N. Mizerovskii ◽  
V. G. Silant'eva ◽  
T. S. Usachev ◽  
Yu. S. Paikachev ◽  
N. V. Sholichev ◽  
...  
2014 ◽  
Vol 955-959 ◽  
pp. 2926-2930
Author(s):  
Lin Pei Dong ◽  
Ji Ling Zhan ◽  
Xin Li

This article studied the dehydration effect of elutriation sludge produced in the process of cultivating aerobic granular sludge, which is a joint regulation of cationic polyacrylamide (CPAM) and modified coal fly ash, using sludge specific resistance(SRF) and moisture content of sludge extent as the target. The results show that the greater the relative molecular weight, the better effect is. CPAM whose relative molecular weight is 8 million is the best type when solo casted. When casted by15 mg/L, SRF is reduced to 0.43×108 S2/g, The 1 g/L coal fly ash and 15 mg/L 8 million CPAM joint control, SRF is reduced to 0.4×108 S2/g, moisture content is 72.04%. When using modified coal fly ash, the result is better. Modified coal fly ash can effectively promote the efficiency of CPAM as the coagulant aid. It can further reduce SRF and moisture content of the sludge. We can observe the effects modified coal fly ash joint CPAM has on elutriation sludge morphology by scanning electron microscopy (SEM).


2011 ◽  
Vol 83 (2) ◽  
pp. 934-939 ◽  
Author(s):  
Kiyoshi Kawai ◽  
Ken Fukami ◽  
Pariya Thanatuksorn ◽  
Chotika Viriyarattanasak ◽  
Kazuhito Kajiwara

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Yan-jiang Jin ◽  
Ben-xian Shen ◽  
Ruo-fan Ren ◽  
Lei Yang ◽  
Jun Sui ◽  
...  

The effect of the amounts of initiator, emulsifier, and molecular weight regulator on the styrene butadiene rubber performance was investigated, based on the industrial original formula. It was found that the polymerization rate was increased with the increased dosage of initiator and emulsifier, and together with replenishing molecular weight regulator will make the Mooney viscosity of rubber meet the national standard when the conversion rate reaches 70%. The backpropagation neural network was trained by the original formula and ameliorated formula on the basis of Levenberg-Marquardt algorithm, and the relative error between the simulation results and experimental data is less than 1%. The good consistency shows that the BP neural network could predict the product performances in different formula conditions. It would pave the way for adjustment of the SBR formulation and prediction of the product performances.


2020 ◽  
Vol 30 (2) ◽  
pp. 112-121 ◽  
Author(s):  
R. Umarani ◽  
M. Bhaskaran ◽  
C. Vanitha ◽  
M. Tilak

AbstractSeed is a fertilized mature ovule, which possesses an embryonic plant. When the dry, mature seeds are subjected to imbibition, they release a wide range of organic substances, which include low molecular weight carbonyl compounds (gases and volatiles) and water-soluble organic substances (enzymes and polysaccharides). The volatile organic compounds (VOCs) are molecules of low molecular weight (300 g mol−1) and high vapour pressure (0.01 kPa at 20°C) and include diverse chemical compounds. The nature and emission kinetics of volatiles produced from seeds vary, depending on the moisture content of the seeds. Orthodox seeds stored at ‘low seed moisture content’ undergo seed deterioration, predominantly due to lipid peroxidation, initiated by autoxidation or enzymatic oxidation of unsaturated or polyunsaturated fatty acids. This peroxidation leads to emission of volatile compounds. The quantity of VOCs emitted is positively correlated with the advancement of seed deterioration. With respect to the seed germination process, exposure of seeds to ‘high moisture conditions’ leads to increased respiration, triggers glycolysis and mobilization of storage reserves, resulting in the emission of volatile metabolic products. The quantity of VOCs emitted on commencement of metabolic activity in germinating seeds depends on (1) vigour status and (2) amount of storage reserves. Since it has been established that there is a significant difference between high and low vigour seeds with respect to quantity and profile of VOCs emitted, there is great potential for utilizing the VOC profile to obtain a quick and reproducible test of vigour status of crop seeds. In order to harness the VOC profile for quick assessment of vigour status of seeds, research has to be taken up to develop standard protocols for fingerprinting of VOCs for the purpose of seed vigour assessment and to fix the standard volatile biomarker(s) specific to crop and vigour status of seeds.


2011 ◽  
Vol 194-196 ◽  
pp. 1529-1535 ◽  
Author(s):  
Jian Qiang Li ◽  
Ru Quan Zhang ◽  
Xiao Jie Zhou ◽  
Dai Qi Li

Keratins from wool were reduced by the optimize method(PH 7.0, NaHSO350wt%, Urea 200wt% and SDS 15wt%), wool 5g, distilled water100mL, shaken at 80°C inconstant temperature water-bath for 24h, filtered through different nylon screens with 50-300 aperture using decompression filtering, dialyzed against distilled water afford a colorless and clear solution. The keratins main molecular weight was 35,000-45,000 Daltons; a clear film is readily prepared from a keratin solution containing glycerol or PEG on the basic of SMS nonwovens; the films moisture content was changed while glycerol concentration changed from 5% to 25%; the film was insoluble in water and organic solvents. The films were tested by SEM, Ultraviolet and FTIR.


Author(s):  
Dmitry Belov

The synthesis of additives for thinning mineral suspensions based on sodium polyacrylate was carried out. The effect of molecular weight regulators on the molecular weight characteristics of the polymer and the effect of such polymers on the rheological properties of suspensions was studied. Sodium acrylate polymers are synthesized by free radical polymerization in aqueous solution using molecular weight regulators. The molecular weight characteristics of the polymeric samples were estimated by viscometry using Mark-Houwink-Kuhn-Sakurada (MHKS) equation. Synthesized polymers were used as thinners ceramic slurries, prepared according to the recipe of the enterprises producing ceramic products. The thinning ability of polymer samples with different molecular weights was estimated using an Engler viscometer from the time of the ceramic slurry flow. The influence of the type and amount molecular weight regulator on polyacryates was revealed. It was found that molecular weight synthesized samples was in the range of 21000 - 91000. It was determined that samples with a molecular weight of 28000 - 35000 synthesized using mercaptoethanol (at a dosage of 0.5-1.5% by weight of the monomer) provide optimal fluidity to the ceramic slurry.


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