Sedimentation stability of clayless enamel slip based on polyacrylamide

In-situ sol-gel method to prepare colloidal hybrids of surfactant modified polysucchride and titanium oxide has been presented, and experiments indicated these highly ER active particles exhibited a remarkable ER effect. The static shear stress can be up to 37 k Pa (shear rate 5 S -1) under DC field of 4 kV/mm at root temperature, well above that of simple blends of starch and TiO 2. In the meanwhile, temperature dependence and sedimentation stability were also greatly improved. Based on recent experimental facts, we find that dielectric properties and surface (interface) activity are two necessary conditions fulfilling the requirement of high ER activity. Adequate grinding of particles with oil can effectively enhance the shear stress, which may be owed to the decline of the activation energy needed for restructuring. It has provided us a new horizon for preparation of excellent ER materials and further studies should be continued to make.

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INFLUENCE OF MORPHOLOGY, PHASE COMPOSITION AND CONTENT OF ALUMINUM OXIDE PARTICLES ON RHEOLOGICAL PROPERTIES OF AQUEOUS SUSPENSIONS BASED ON THEM

Aviation Materials and Technologies ◽

10.18577/2713-0193-2021-0-4-14-25 ◽

2021 ◽

pp. 14-25

Author(s):

V.A. Voronov ◽

◽

A.S. Chainikova ◽

Yu.E. Lebedeva ◽

D.M. Tkalenko ◽

...

Keyword(s):

Phase Composition ◽

Aluminum Oxide ◽

Aggregate Stability ◽

Plasma Chemical ◽

Buffer Solution ◽

Sedimentation Stability ◽

Aqueous Suspensions ◽

Oxide Powders ◽

Ceramic Samples ◽

Oxide Particles

This work investigated the chemical and phase composition of aluminum oxide powders obtained by various methods (alkoxide, codeposition, thermal and plasma-chemical). The physicomechanical, thermophysical and thermal properties of ceramic samples based on them have been determined. The effect of the nature of the aluminum oxide powder and the production process parameters on the sedimentation stability of aqueous suspensions based on them has been determined. The influence of the content of particles of aluminum oxide, buffer solution and rheological additives on the viscosity, sedimentation and aggregate stability of aqueous suspensions has been determined.

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Synthesis of calcium ferrite nanocrystal clusters for magnetorheological fluid with enhanced sedimentation stability

Powder Technology ◽

10.1016/j.powtec.2017.08.065 ◽

2017 ◽

Vol 322 ◽

pp. 47-53 ◽

Cited By ~ 24

Author(s):

Guangshuo Wang ◽

Dexing Zhao ◽

Yingying Ma ◽

Zhixiao Zhang ◽

Hongwei Che ◽

...

Keyword(s):

Magnetorheological Fluid ◽

Calcium Ferrite ◽

Sedimentation Stability

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Application of synthetic and grafted polymeric flocculants in agricultural wastewater treatment

Journal of Degraded and Mining Lands Management ◽

10.15243/jdmlm.2021.083.2829 ◽

2021 ◽

Vol 8 (3) ◽

pp. 2829-2836

Author(s):

Mohamed N Ali ◽

Mohammed S Fahmy ◽

Rehab M Elhefny

Keyword(s):

Activated Sludge ◽

Agricultural Sector ◽

Aeration Tank ◽

Activated Sludge Process ◽

Sedimentation Stability ◽

Agricultural Wastewater ◽

High Concentrations ◽

Filtration Stage ◽

Organic Particles ◽

Low Dosage

Due to the large amounts of freshwater consumed in Egypt by the agricultural sector that is more than 85% of Egypt share of freshwater in addition to the high concentrations of salts, chemicals and nutrients produced from fertilizers. Reduction of these pollutants concentrations to an acceptable level and breaking the sedimentation stability of colloidal substances and organic particles for reuse for irrigation purposes was associated with the application of biological treatment with coagulants addition. The flocculation process was performed by using polydiallyldimethylammonium chloride (polyDADMAC) and polyacrylamide grafted oatmeal (OAT-g-PAM). The scale-pilot consists of an aeration tank equipped with an air blower, sedimentation tank followed by a filtration stage through 20 cm of pottery scrubs media. To study the performance of synthetic and grafted polymeric flocculants, 3 trials were performed. Activated sludge process without adding any polymeric flocculants was the control trial. In the second trial, polyDADMAC was added with a dose of 5 mg/l. Finally, OAT-g-PAM with a dose of 1.25 mg/l was used in the third trial. The physicochemical properties of agricultural wastewater were measured at the national research center in Cairo. It was found that OAT-g-PAM incorporated with activated sludge process was the most effective in treating agricultural wastewater as it achieved COD, BOD,TKN, TP, and TSS removal efficiency up to 92.29%, 93.13%, 90.64%, 90.46%, and 92.5%, respectively which made it suitable to reuse for agricultural purposes, in addition to its ability to biodegrade, environmentally friendly, and low dosage required compared to polyDADMAC.

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Impulsively-Laser Excitation and Propagation of Ultrasonic Waves through Nanomagnetic Fluid

Devices and Methods of Measurements ◽

10.21122/2220-9506-2021-12-3-211-219 ◽

2021 ◽

Vol 12 (3) ◽

pp. 211-219

Author(s):

A. R. Baev ◽

A. I. Мitkovets ◽

M. V. Asadchaya ◽

A. L. Mayorov

Keyword(s):

Laser Radiation ◽

Boundary Conditions ◽

Magnetic Fluid ◽

Colloidal Particles ◽

Laser Excitation ◽

Magnetic Fluids ◽

Ultrasonic Waves ◽

Dispersed Phase ◽

Transformation Mechanism ◽

Sedimentation Stability

Magnetic fluids belong to the class of nanomaterials with a high gain of light absorption, aggregative and sedimentation stability as well as controllability by external fields, which is of interest to use in the field of optoacoustics. The purpose of the work was to experimentally study the effect of the optoacoustic transformation in a magnetic fluid, depending on the concentration of magnetic colloidal particles, boundary conditions, intensity of the laser as well as to identify the possibilities of using the magnetic fluid as an element of the optoacoustic transformation in a number of applications.A brief analysis of the optoacoustic transformation mechanism in a magnetic fluid was carried out and a technique and an installation that implements the shadow measurement variant developed. A Lotis type laser was used as a source of ultrasonic pulse-laser excitation in magnetic fluids. A quartz and air were used as a material transmitting the energy of laser radiation in a magnetic fluid. Receiving of ultrasound signals was made by a piezoelectric probe at a working frequency of 5 MHz. In the measurement process, the concentration of the dispersed phase in tmagnetic fluid was varied from zero to 8 % and the energy in the impulse – from zero to 10 mJ.For the first time, it was established that: a) an amplitude of the function of the optoacoustic transformation in a magnetic fluid, depending on the concentration of the dispersed phase, has a maximum determined by the fluid physical properties and boundary conditions; b) for all samples within the measurement error, a quasilinear dependence of the specified amplitude of energy in the laser pulse in the range of 0–8 MJ has been established.A number ways of the optoacoustic effects in magnetic fluids to use in ultrasonic testing, measuring the intensity of the laser radiation had been suggested.

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Research on characterization method and influencing factors of sedimentation stability of magnetorheological fluid

Korea-Australia Rheology Journal ◽

10.1007/s13367-021-0024-y ◽

2021 ◽

Vol 33 (4) ◽

pp. 309-320

Author(s):

Yuqing Li ◽

Yiping Luo ◽

Ying Wang ◽

Jiao Luo ◽

Yameng Chen

Keyword(s):

Influencing Factors ◽

Magnetorheological Fluid ◽

Sedimentation Stability

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Highly Crystalline WO3 Nanoparticles Are Nontoxic to Stem Cells and Cancer Cells

Journal of Nanomaterials ◽

10.1155/2019/5384132 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

B. Han ◽

A. L. Popov ◽

T. O. Shekunova ◽

D. A. Kozlov ◽

O. S. Ivanova ◽

...

Keyword(s):

Stem Cells ◽

Tungsten Oxide ◽

Cell Lines ◽

Colloidal Solutions ◽

Sedimentation Stability ◽

Ultrasonic Assisted ◽

Low Cytotoxicity ◽

Theranostic Applications

Tungsten oxide sol, containing highly crystalline nanoparticles of orthorhombic WO3 and having good sedimentation stability, was synthesized using a facile, ultrasonic-assisted technique. An additional steric stabilizer, dextran, was proposed to enhance the stability of WO3 nanoparticles in biological media and to reduce their in vivo toxicity. The cytotoxicity of dextran-stabilized and nonstabilized WO3 sols was studied in vitro using dental pulp stem (DPS) cell lines and breast cancer (MCF-7) cell lines. Both tungsten oxide sols demonstrated low cytotoxicity and low genotoxicity for both stem cells and malignant cells and only slightly reduced their metabolic activity in the concentration range studied (from 0.2 to 200 μg/ml). The data obtained support possible theranostic applications of tungsten oxide colloidal solutions.

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Research and Application of Ultra-High Cementing Slurry

Materials Science Forum ◽

10.4028/www.scientific.net/msf.847.485 ◽

2016 ◽

Vol 847 ◽

pp. 485-489

Author(s):

Xing Cai Zhang ◽

Xiao Wei Cheng ◽

Xiao Yang Guo

Keyword(s):

High Temperature ◽

Oil And Gas ◽

Good Effect ◽

Fluid Loss ◽

Cement Slurry ◽

Sedimentation Stability ◽

Temperature Resistance ◽

Deep Wells ◽

High Temperature Resistance ◽

Shallow Wells

With the exploration of oil and gas in depth, shallow wells already can’t satisfy the requirement, therefore to explore and develop deep reservoirs is necessary. In the case of deep wells the loop temperature of bottom can reach to 150°C-200°C, which put forward a higher requirement for the high temperature resistance property of cement slurry. At present, many problems existed in the most of high temperature cement slurry. For example, high temperature resistance is not well, cement thickening time can’t adjust easily, mega-thermal sedimentation stability is unsatisfactory, and ultra-retarding phenomenon appeared for the top prone. After research indoors, we developed the ultra-high temperature slurry system by means of the investigation on cementing additives and select proper materials from high temperature resistant fluid loss additives, retarders, flowable agent at the same time. This system needs a lots of properties, such as, adjustable slurry thickening time below 200°C, great slurry sedimentation stability, API loss can be controlled at the range of 0-50ml, insensitive to temperature and density, could be used in low-density and conventional density cement etc. This system be used successfully in the well that loop temperature of bottom reaches to 185°C and get a good effect finally.

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