scholarly journals PLASTIFICATION OF DUSTED QUARTZ BY RECHARGING ITS SURFACE

2021 ◽  
Vol 1 (69) ◽  
pp. 30-32
Author(s):  
M. Ananev ◽  
L. Zakrevskaya ◽  
K. Nikolaeva
Keyword(s):  
High Strength ◽  
Quartz Surface ◽  
Gravitational Flow ◽  
Mineral Particles ◽  
System A ◽  
Water Suspensions

To ensure the gravitational flow of the system, a method of non-mechanical disaggregation of mineral particles was used in order to obtain high-strength concretes with a reaction-powder bond and with minimal W / T and W / C ratios. The technology of plasticizing highly filled quartz-water suspensions consists in recharging the quartz surface and includes the following operations: dispersing the mixture into fractions (0.163 mm; 0.315 mm), adding a plasticizer, mixing and shaping the mixture. Evaluation of rheotechnological properties of water-calcium, water-quartz and water-calcium-quartz suspensions, characterized by the spread of the mixture from 64.5 mm to 29.5 mm.

A Magnetic Bearing Suspension System for High Temperature Gas Turbine Applications: Part III — Magnetic Actuator Development

1997 ◽  
Author(s):  
William P. Kelleher ◽  
Anthony S. Kondoleon
Keyword(s):  
High Temperature ◽  
Gas Turbine ◽  
Copper Wire ◽  
High Vacuum ◽  
High Strength ◽  
Magnetic Bearing ◽  
Suspension System ◽  
Control Power ◽  
System A ◽  
Turbine Shaft

Magnetic bearings, unlike traditional mechanical bearings, consist of a series of components when mated together, form a stabilized system. A series of four papers will summaries the results carried out at Draper in the development of a high temperature magnetic bearing suspension system for a gas turbine application. Part I [1] will document our approach for rotordynamics modeling of the turbine shaft and the development of models for use in our simulation programs. Part II [2] documents the simulation efforts and the control system which resulted from this effort. Parts III and IV [3] document the design and fabrication of the magnetic bearing actuators and the auxiliary touchdown bearings. This paper, part III, deals with the design of the high temperature magnetic bearing actuators. Two radial and one axial magnetic bearing actuator were designed to meet the requirements for the turbine application. No bias coils are included in these design. The biasing flux is provided by current from the control power amplifiers. All the coils are made from ceramic coated copper wire and are terminated to high temperature connectors designed into the actuators. The new high strength Hiperco 50 HS material was chosen for the rotor lamination material for the radial bearings. A customized heat treatment process for this material in a high vacuum environment was developed to insure the maximum strength was obtained with the maximum magnetic properties. High temperature ceramic coated copper wire and bonding and potting material used for the coil assembly were tested up to 650 degrees C without failures.

Use of sonication to determine the size distributions of soil particles and organic matter

2009 ◽  
Vol 89 (4) ◽  
pp. 413-419 ◽  
Author(s):  
X M Yang ◽  
C F Drury ◽  
W D Reynolds ◽  
D C MacTavish
Keyword(s):  
Particle Size ◽  
Organic Matter ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Size Distributions ◽  
Silt Loam ◽  
Clay Loam ◽  
Mineral Particles ◽  
Water Suspensions ◽  
Primary Mineral

Applying ultrasound energy to soil-water suspensions (sonication) is an established method of determining the size distributions of soil primary mineral particles and associated organic matter. The size distributions may vary, however, with sonication input energy and soil type. The objective of this study was to determine the effects of sonication input energy on the size distributions of soil mineral particles and organic matter for a range of soil textures and carbon contents typical of agricultural soils in southwestern Ontario. The soils included a Brookston clay loam, a Brookston clay, a Huron silt loam, a Perth silt loam and a Harrow sandy loam. All soils were under no-tillage management. Nine sonication energies ranging from 50 to 1500 J mL–1 were applied to soil-water suspensions (1:4 mass ratio), and the soil particle size distribution results were compared with those obtained using the standard chemical dispersion (pipette) method. The three medium- and coarse-textured soils (Huron, Perth, Harrow) required about 250 J mL–1 for complete dissociation of soil aggregates, while the two fine-textured soils (Brookston) required sonication energies of 600-750 J mL–1. Increasing sonication energy increased the amount of soil organic carbon (SOC) measured in the clay-size fraction and decreased the amounts in the sand and silt fractions. Therefore, accurate determinations of particle size distribution and SOC contents require an initial assessment of the amount of sonication energy required for the complete dispersion of the particle size fractions. For the Brookston clay loam and Brookston clay soils, 40–52% less particulate SOC was found in the sand fraction at 750 J mL–1 sonication energy than that obtained using the standard pipette method, indicating particle size reduction by sonication of particle organic matter. It should be noted that the sand-size SOC typically represents a small fraction. Furthermore, sonication had a minor effect on the SOC content of the clay fraction. It was concluded that sonication is a viable technique for determining the size distribution of soil primary mineral particles, as well as the amount of SOC associated with the silt and clay fractions. Key words: Sonication, ultrasound energy, particle size distribution, organic carbon fractionation, clay soil

Graded Anodic Film Morphologies for Sustainable Exploitation of Aluminium Alloys in Aerospace

2008 ◽  
Vol 38 ◽  
pp. 48-55 ◽  
Author(s):  
Michele Curioni ◽  
Peter Skeldon ◽  
George E. Thompson ◽  
John Ferguson
Keyword(s):  
Aluminium Alloys ◽  
High Strength ◽  
Alloy System ◽  
Alloying Elements ◽  
Anodic Film ◽  
Localized Corrosion ◽  
Second Phase ◽  
System A ◽  
Multiphase Alloy ◽  
Low Weight

High strength aluminium alloys are widely used in the civil and military aerospace industry due to their low weight and high mechanical properties, achieved by selected alloying elements and heat treatments. The resulting multiphase alloy system, a solid solution of alloying elements in the aluminium matrix and a variety of second phase material, requires specific anticorrosion measures in order to prevent localized corrosion, which is promoted by microgalvanic coupling between the different metallographic phases. Traditionally, the anticorrosion performances are achieved by chromic acid anodizing (CAA), followed by painting. However, environmental issues and associated costs for the disposal of chromate wastes, require the development of new approaches for anodizing of aluminium alloys. In this work, the potential for tailoring the porous anodic film morphology through the film thickness by controlled variations of the anodizing potential is inspected. The procedure developed is, in principle, applicable to any aluminium alloy in any anodizing electrolyte and results in the generation of innovative graded porous anodic film morphologies which promise improvement of anticorrosion properties and replacement of CAA .

Reduction of Combined Sewer Overflow Pollution Loads by Detention of Sanitary Sewage

1990 ◽  
Vol 22 (10-11) ◽  
pp. 205-212
Author(s):  
W. Schilling ◽  
D. T. Kollatsch
Keyword(s):  
High Strength ◽  
Chemical Transformations ◽  
Storage Tanks ◽  
Combined System ◽  
System A ◽  
Sewer Systems ◽  
Combined Sewer ◽  
Separate System ◽  
Using Data ◽  
Operational Aspects

For mixed combined/separate sewer systems it is proposed, in times of combined sewage overflows (CSO), to store sanitary sewage at the inlet point to the combined system. Thereby, sanitary sewage (with high strength) is kept in the system for further treatment after the storm whereas less-polluted CSO are diverted to the receiving water. By using data of an existing catchment different scenarios are evaluated and the potential benefit of sanitary sewage detention is quantified. This approach is compared to current German CSO regulations. It is more effective than conventional CSO detention if more than 60 % of the population upstream of the CSO diversion are served by a separate system. A key problem of this concept is the control strategy that determines when to activate and empty the storage tanks. A number of criteria are compared. Considerations are also made on operational aspects such as chemical transformations in stored sewage, maximum allowable detention time, and cleansing of storage tanks.

Research on Function Aggregate Prepared by Steel Wastewater Sludge

2010 ◽  
Vol 168-170 ◽  
pp. 1625-1630
Author(s):  
Qing Jun Ding ◽  
Xiu Lin Huang ◽  
Hua Sun ◽  
Kun Yang
Keyword(s):  
Heavy Metals ◽  
Optimization Design ◽  
High Strength ◽  
Radiation Shielding ◽  
Wastewater Sludge ◽  
Raw Material ◽  
Linear Attenuation Coefficient ◽  
System A ◽  
Zn Content ◽  
Novel Method

Industrial wastewater sludge contains a certain amount of heavy metals, which will cause environmental pollution. In this paper high Cr, Zn content wastewater sludge from steel plant was used as the main raw material, with Kaolin and other materials as adjustment materials. Through optimization design of raw mix composition and firing system, a kind of function aggregate was got, which had an apparent relative density of about 3.0 g/cm3, a vacuum water absorption between 16%~23%, and a linear attenuation coefficient more than 0.15cm-1. Use XRD and SEM to analyze the existence state of heavy metals in aggregates. The novel method for making function aggregates provides a technical support for resource utilization of steel wastewater sludge, which could be applied in the field of high strength concrete and radiation shielding concrete.

Technologies for urban water recycling

2008 ◽  
Vol 3 (2) ◽  
Author(s):  
Marc Pidou ◽  
Fayyaz Ali ◽  
Ronnie Frazer Williams ◽  
Paul Jeffrey ◽  
Tom Stephenson ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Constructed Wetlands ◽  
Biological System ◽  
Membrane Bioreactor ◽  
High Strength ◽  
Chemical Reactor ◽  
Chemical System ◽  
Urban Water ◽  
Reed Beds ◽  
System A

This paper presents a comparative analysis of 5 systems for the treatment of greywater for reuse. The systems investigated were a biological system: a membrane bioreactor (MBR), a chemical system: a membrane chemical reactor (MCR) and three constructed wetlands: vertical (VFRB) and horizontal (HFRB) flow reed beds and a green roof (GROW). The results revealed that the GROW and the HFRB achieved a limited treatment of the greywater. Alternatively, the MBR, the MCR and the VFRB achieved a good general treatment of the greywater. However, the MBR and MCR alter more significantly the solids and microbial fractions. Overall, the MBR was found to be the most suitable technology for greywater recycling due to its robustness. Indeed, the MBR constantly achieved an excellent treatment of the high strength greywater.

Study on Mechanical Behavior of Floor Beams in the High-Strength Cold-Formed Steel Framing System

2011 ◽  
Vol 71-78 ◽  
pp. 3489-3494
Author(s):  
Yao Jie Guo ◽  
De Wei Zeng ◽  
Yan Zhou Chen
Keyword(s):  
Finite Element ◽  
Mechanical Behavior ◽  
Shell Element ◽  
High Strength ◽  
Plastic Shell ◽  
Loading Test ◽  
System A ◽  
Steel Framing ◽  
Practical Engineering ◽  
Cold Formed Steel

Tests and the finite element method (FEM) have been used to research the mechanical behavior of floor beams in the new cold-formed steel framing system. A group of 3 floor beams have been carried loading test to obtain ultimate bearing capacity, then finite element models, using plastic shell element and simultaneous considering material and geometric nonlinearity in ANSYS, have been established to analyze the mechanical behavior of floor beams. Finally, the ultimate uniform loads are given for the various specifications of floor beams, for practical engineering design.

scholarly journals Experimental investigation on burr formation in vibration-assisted micro-milling of Ti-6Al-4V

2018 ◽  
Vol 233 (12) ◽  
pp. 4112-4119 ◽  
Author(s):  
Lu Zheng ◽  
Wanqun Chen ◽  
Dehong Huo
Keyword(s):  
High Strength ◽  
Resonant Mode ◽  
Micro Milling ◽  
Burr Formation ◽  
Machining Accuracy ◽  
Tool Wear Rate ◽  
Slot Milling ◽  
System A ◽  
Mode Vibration ◽  
Vibration Parameters

Titanium alloys have been widely used in aerospace, marine and medical industries, due to their high strength, good corrosion resistance and excellent heat resistance. High tool wear rate and low machining accuracy limits conventional micro-milling to meet increasing stringent demand. In this paper, a prototype of two-directional vibration stage and its control system are developed for non-resonant mode vibration-assisted micro-milling system. A series of slot milling experiments are carried out to investigate the effects of vibration parameters on burr generation. The results show that vibration-assisted micro-milling is an effective way to reduce burr size when choosing appropriate vibration parameters and directions.

Decomposition of the metastable beta titanium alloy Ti-15-3

1983 ◽  
Vol 41 ◽  
pp. 264-265
Author(s):  
Y. L. Chen ◽  
S. Fujlshiro
Keyword(s):  
Low Cost ◽  
High Strength ◽  
Alpha Phase ◽  
Thick Sheet ◽  
Omega Phase ◽  
Beta Titanium Alloy ◽  
Beta Titanium ◽  
Beta Matrix ◽  
Metastable Beta ◽  
Very High

Metastable beta titanium alloys have been known to have numerous advantages such as cold formability, high strength, good fracture resistance, deep hardenability, and cost effectiveness. Very high strength is obtainable by precipitation of the hexagonal alpha phase in a bcc beta matrix in these alloys. Precipitation hardening in the metastable beta alloys may also result from the formation of transition phases such as omega phase. Ti-15-3 (Ti-15V- 3Cr-3Al-3Sn) has been developed recently by TIMET and USAF for low cost sheet metal applications. The purpose of the present study was to examine the aging characteristics in this alloy.The composition of the as-received material is: 14.7 V, 3.14 Cr, 3.05 Al, 2.26 Sn, and 0.145 Fe. The beta transus temperature as determined by optical metallographic method was about 770°C. Specimen coupons were prepared from a mill-annealed 1.2 mm thick sheet, and solution treated at 827°C for 2 hr in argon, then water quenched. Aging was also done in argon at temperatures ranging from 316 to 616°C for various times.

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