Effects of charged water-soluble polymers on the stability and activity of yeast alcohol dehydrogenase and subtilisin Carlsberg

2001 ◽  
Vol 76 (3) ◽  
pp. 241-246 ◽  
Author(s):  
Trudi M. Foreman ◽  
Mona Khalil ◽  
Paul Meier ◽  
James R. Brainard ◽  
Laura A. Vanderberg ◽  
...  
Keyword(s):  
Alcohol Dehydrogenase ◽  
Water Soluble ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
Yeast Alcohol Dehydrogenase ◽  
Subtilisin Carlsberg ◽  
The Stability ◽  
Charged Water

scholarly journals Improvement of Foaming Ability of Surfactant Solutions by Water-Soluble Polymers: Experiment and Molecular Dynamics Simulation

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 571 ◽  
Author(s):  
Chaohang Xu ◽  
Hetang Wang ◽  
Deming Wang ◽  
Xiaolong Zhu ◽  
Yunfei Zhu ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Water Soluble ◽  
Dynamics Simulation ◽  
Foaming Agents ◽  
Water Soluble Polymers ◽  
Foaming Ability ◽  
Soluble Polymers ◽  
Aqueous Foam ◽  
Surfactant Solutions ◽  
The Stability

Aqueous foam is widely used in fire extinguishing and dust suppression technologies. Improving the foaming ability is the key to reducing the added concentration of foaming agents as well as the economic cost. In this work, the effect of a water-soluble polymer (polyvinyl alcohol, PVA) on the foaming ability of anionic surfactant (sodium dodecyl ether sulfate, SDES) was studied by an experiment and molecular dynamics simulation. The experimental results showed that PVA greatly improves the foaming ability of SDES solutions when the surfactant concentration is less than 0.1%, which is attributed to the fact that the polymer can enhance the stability of bubble films and reduce the bubble rupture rate during the foam generation process. The simulation results indicate that PVA can enhance the hydration of surfactant head groups and contribute to the formation of a three-dimensional hydrogen bond network between surfactants, polymers, and water molecules, thus greatly improving the stability of bubble liquid films. The above results suggest that water-soluble polymers can be used to improve the foaming ability of surfactant solutions by enhancing the bubble film stability, which is beneficial as it reduces the added concentration of foaming agents in aqueous foam applications.

Improving Gas Bubbles’ Half Life in Foam Drilling Fluid

2013 ◽  
Vol 62 (1) ◽  
Author(s):  
Issham Ismail ◽  
Nur Suriani Mamat ◽  
Baihaqi Mamat ◽  
Ahmad Shamsulizwan Ismail ◽  
Azmi Kamis ◽  
...  
Keyword(s):  
Rheological Properties ◽  
Xanthan Gum ◽  
Drilling Fluid ◽  
Water Soluble ◽  
Polymer Foam ◽  
Water Soluble Polymers ◽  
Stable Foam ◽  
Soluble Polymers ◽  
The Stability ◽  
Foam Drilling

An underbalanced drilling using foam drilling fluid is one of the most effective solutions which are capable of preventing formation damage, differential sticking, or circulation lost. Nevertheless, the limitation of using foam drilling fluid is the stability of its rheological properties which would affect its lubricity characteristics. Therefore, a research study was carried out to determine the stability and effectiveness of water soluble polymers as an additive in foam drilling fluid. To produce the required and most stable foam, four types of surfactants had been tested, namely sodium dodecyl sulfate (anionic), cetyltrimethylammonium bromide (cationic), T×100 (non ionic), and n-alkyl betaines (amphoteric). Then, the water soluble polymers, namely xanthan gum, hydroxyethyl cellulose, guar gum, and carboxymethyl cellulose, were evaluated as a stabilizer in the said foam drilling fluid. The laboratory works involved lubricity and rheological properties tests, which were conducted at ambient condition. The experimental results showed that the use of xanthan gum with anionic surfactant produced the most stable foam drilling fluid compared to other polymers. Rheological properties of the polymer foam drilling fluid were compared with water-based mud, and it was revealed that polymer foam drilling fluid could perform as effective as the latter. The significant advantage of using polymer foam drilling fluid was its coefficient of friction which was found to be lower than the water-based mud. 

Influence of Viscosity-Modifying Admixtures on the Thixotropic Behaviour of Cement Pastes

2008 ◽  
Vol 18 (4) ◽  
pp. 45604-1-45604-8 ◽  
Author(s):  
R. Bouras ◽  
M. Chaouche ◽  
S. Kaci
Keyword(s):  
Rheological Properties ◽  
Cement Paste ◽  
Water Soluble ◽  
Mix Design ◽  
Scale Level ◽  
Cement Pastes ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
Thixotropic Behaviour ◽  
The Stability

Abstract Water soluble polymers such as cellulosic or starch ethers are often included in the mix-design of Self Compacting Concretes (SCCs) in order to improve their stability and robustness. The stability, including resistance to liquid-solid separation and sedimentation, may be attributed to the increase of the viscosity of the liquid phase due to the thickening effect of the polymer. The later is then referred to as a Viscosity-Modifying Admixture (VMA). In the present study, we consider the influence of VMAs on the rheological properties of the material at cement scale level. In particular, the change in the thixotropic properties of the cement paste due to the inclusion of VMA is investigated. It is found that addition of VMA significantly enhances rebuild-up kinetics at rest following shearing at high shear rate. The influence of VMA on the steady state rheological properties is also considered. As reported in the literature, the yield stress is found to monotonically increase with VMA content, while the consistency presents a minimum indicating the existence of an optimum value of the VMA for which the workability of the cement paste is maximum.

Experimental Study of the Insulating Properties of a Lightweight Material Based on Fast-Hardening Highly Resistant Foams in Relation to Vapors of Toxic Organic Fluids

2021 ◽  
Vol 1038 ◽  
pp. 374-382
Author(s):  
Ruslan Pietukhov ◽  
Alexander Kireev ◽  
Dmytro Tregubov ◽  
Serhii Hovalenkov
Keyword(s):  
Experimental Study ◽  
Carboxymethyl Cellulose ◽  
Water Soluble ◽  
Mass Rate ◽  
Foaming Agent ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
The Stability ◽  
Organic Fluids ◽  
Insulating Properties

To isolate the surface of toxic liquids, it is proposed to use fast-hardening highly resistant foams. To obtain fast-hardening, highly resistant foams, the process of gel and foaming is combined. For this, solutions of sodium polysilicate and gelation catalyst are mixed. To increase the stability of the foams, it is proposed to add water-soluble polymers to the gel-forming composition. It is shown that a fast-hardening foam of the composition Na2O·2.5SiO2 (9%)+NaHCO3 (9%)+6% foaming agent +0.5% carboxymethyl cellulose with thickness reduces the mass rate of benzene evaporation by more than 5 times. It retains its insulating properties for more than 5 days. It is concluded that it is advisable to use fast-hardening highly resistant foams for the elimination of emergencies with the spill of toxic liquids.

New quenching media based on water-soluble polymers

1981 ◽  
Vol 23 (2) ◽  
pp. 104-106 ◽  
Author(s):  
A. V. Tolstousov ◽  
O. A. Bannykh
Keyword(s):  
Water Soluble ◽  
Water Soluble Polymers ◽  
Soluble Polymers ◽  
Quenching Media

scholarly journals SANS quantification of bound water in water-soluble polymers across multiple concentration regimes

Soft Matter ◽  
2021 ◽  
Author(s):  
Helen Yao ◽  
Bradley D. Olsen
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Bound Water ◽  
Water Soluble ◽  
Wide Concentration Range ◽  
Water Molecules ◽  
Water Soluble Polymers ◽  
Soluble Polymers

Small-angle neutron scattering is used to measure the number of bound water molecules associating with three polymers over a wide concentration range. Different fitting workflows are evaluated and recommended depending on the concentration regime.

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