scholarly journals Development of smelting technology of refined ferromanganese with special complex reducing agents

2018 ◽  
Vol 61 (9) ◽  
pp. 689-694
Author(s):  
S. O. Baisanov ◽  
A. S. Baisanov ◽  
A. Z. Isagulov ◽  
D. A. Esengaliev ◽  
N. I. Ospanov
Keyword(s):  
Experimental Studies ◽  
Reducing Agents ◽  
Reducing Agent ◽  
Added Value ◽  
Smelting Process ◽  
Internal Stresses ◽  
Technological Parameters ◽  
The Stability ◽  
Special Complex

The role of manganese in the production of steel is exceptionally high. A feature of the silicothermic process of obtaining refined ferromanganese is the large loss of manganese with waste slag. When waste slag is cooled, it crumbles to form a fine dust due to the polymorphic transformation of calcium orthosilicate β-Ca2SiO4  →  γ-Ca2SiO4 at temperature of 450  –  470  °С with an increase in volume by 12.3  %. As the volume increases, considerable internal stresses appear inside the slag, which leads to dispersion of the slags into finely dispersed state during their cooling. This work is devoted to improving the technology of smelting refined ferromanganese grades, using special complex reducing agents. Experiments have been carried out to simulate the smelting process of refined ferromanganese in an ore-thermal refining furnace RCO-0.1 MVA using aluminosilicomanganese (ASM). The technological modes of the smelting process are established, i.e. optimal composition of charge. Charge went evenly without collapses and emissions. The stability of the current load was observed. Thus, the principal possibility of obtaining a refined ferromanganese with the use of a complex ASM alloy as a reducing agent was proved by the largelaboratory experimental melting. The use of ASM as a reducing agent, instead of ferrosilicomanganese, is due to the sufficient content of silicon and aluminum in it. The presence of chemical compounds and solid solutions of iron, silicon and aluminum in ASM should significantly reduce losses of silicon and aluminum for oxidation processes when interacting with air oxygen. And involving ASM alloy in the metallurgical redistribution, in refined ferromanganese smelting, instead of expensive ferrosilicomanganese will make it possible to obtain an alloy with high added value and with the best technological parameters, due to the presence of additional aluminum in it. The results of X-ray phase studies of slag samples show that the mineralogical components are gehlenite, dicalcium silicate and manganosite. It is noted that gelenite in them is the dominant phase, which is a solid solution, preventing the dispersion of slag. As a result of the theoretical and experimental studies, the tasks have been solved - the smelting technology of refined ferromanganese was developed and tested using a special complex reducing agent – ASM.

Drag Reducing Agent: A Multi-Use Tool for Liquid Pipeline Companies

1996 ◽  
Author(s):  
David H. Rew ◽  
Steven R. Sandman
Keyword(s):  
Electric Power ◽  
Reducing Agents ◽  
Reducing Agent ◽  
Lessons Learned ◽  
Capacity Increase ◽  
Pipe Line ◽  
Multiple Uses

The role of Drag Reducing Agents (DRA) at Lakehead Pipe Line (LPL) has expanded considerably in recent years. It is now a multi-purpose tool that helps manage electric power usage as well as having traditional capacity increase uses. Indeed, DRA is now an important part of operating the LPL system. This paper examines the multiple uses of DRA as used by LPL. It also describes the structure of the DRA program within the company and provides a summary of “lessons learned” since the DRA program started at LPL in 1991. This information should be useful for anyone who is considering implementing a DRA program.

The dual role of micelles as templates and reducing agents for the fabrication of catalytically active hollow silver nanospheres

2015 ◽  
Vol 51 (4) ◽  
pp. 733-736 ◽  
Author(s):  
Manickam Sasidharan ◽  
Chenrayan Senthil ◽  
Vandana Kumari ◽  
Asim Bhaumik
Keyword(s):  
Catalytic Activity ◽  
Oxidation Reaction ◽  
Triblock Copolymer ◽  
Reducing Agents ◽  
Dual Role ◽  
Reducing Agent ◽  
Silver Nanospheres ◽  
Catalytically Active ◽  
Villiger Oxidation

A simple and efficient protocol for fabrication of colloidal hollow Ag nanospheres of size less than 30 nm using a triblock copolymer in the absence of any reducing agent is reported, which showed excellent catalytic activity in the Baeyer–Villiger oxidation reaction.

Hydrothermal formation of graphene aerogel for oil sorption: the role of reducing agent, reaction time and temperature

2016 ◽  
Vol 40 (4) ◽  
pp. 3040-3046 ◽  
Author(s):  
Wenchao Wan ◽  
Fei Zhang ◽  
Shan Yu ◽  
Ruiyang Zhang ◽  
Ying Zhou
Keyword(s):  
Reaction Time ◽  
Vitamin C ◽  
Reducing Agents ◽  
Reducing Agent ◽  
Graphene Aerogel ◽  
Oil Sorption ◽  
Adsorption Performance ◽  
Graphene Aerogels

Different reducing agents including vitamin C, ammonia and ethanediamine can significantly affect the density, strength, morphology and adsorption performance of graphene aerogels.

Experiments On the Relationship Between the Hen and Chick (Gallus Gallus): the Role of the Auditory Mode in Recognition and the Effects of Maternal Separation

Behaviour ◽  
1987 ◽  
Vol 102 (1-2) ◽  
pp. 1-13 ◽  
Author(s):  
J.P. Kent
Keyword(s):  
Maternal Separation ◽  
Experimental Studies ◽  
Simultaneous Discrimination ◽  
Discrimination Test ◽  
Auditory Mode ◽  
The Stability ◽  
The Relationship ◽  
Second Period ◽  
Hatching Experiment

AbstractIn a series of 6 experimental studies, the means by which a chick recognises its mother, and the reversibility of filial attachments were examined using bantam hens and their chicks. In a simultaneous discrimination test it was determined that the chick could discriminate between own and alien hens by means of the hens' cluck vocalizations, on the 4th and 8th days post hatching, (Experiment 1). The chicks could make this discrimination more efficiently when live hens were presented (Experiment 2). On separating the hen and chicks for 4 h on the 4th day, the chicks could no longer discriminate between own and an alien live hen (Experiment 3) while they would accept an alien hen, (Experiment 4). These findings suggest that maternal-filial bonds may be reversed with little difficulty. Thus Experiment 5 was designed to examine the stability of these later maternal filial bonds. Chicks spent the first 3 days post hatching, with the hen who incubated the eggs. Then they spent 3 days with an alien hen, after which 3 days isolation followed. It was found that chicks could discriminate in favour of their own hen after the first period of exposure, and in favour of the alien hen after the second period of exposure. Following 3 days isolation they showed no preference for either hen. Experiment 6 was essentially a replication of Experiment 5, but included a control for familiarity. Only one test took place after the 3 days isolation. The chicks were presented with the 1st 2nd and an unfamiliar alien hen. The chicks did not discriminate in favour of any particular hen. It is concluded that after 4 h or 3 days isolation, the chicks did not discriminate between the hens presented, yet they remained responsive to hens.

The role of phlogopite in the deep Earth’s water and fluorine cycles

2020 ◽  
Author(s):  
Jiaqi Sun ◽  
Yan Yang ◽  
Qunke Xia
Keyword(s):  
Raman Spectroscopy ◽  
High Temperature ◽  
Powder Diffraction ◽  
Experimental Studies ◽  
Accessory Mineral ◽  
X Ray ◽  
Deep Earth ◽  
The Stability

<p>    Knowledge of the volatiles cycles is vital to understand the evolution of the planet Earth and the life it supports. Although it is gradually accepted that water and other volatiles are recycled into the mantle through subduction, it is still not unclear how these volatiles are transported down into the deep Earth. Phlogopite is an accessory mineral frequently observed in samples from the upper mantle, thereby acting as an important carrier of fluorine and water down to >200 km depth. Previous experimental studies and textural relationships of natural samples have indicated that fluorine-rich phlogopite can be stable under ultra-high-temperature conditions. To further investigate effects of fluorine on the stability of phlogopite, here, we present an atomic level research of effects of fluorine on the structural stability using in situ high temperature infrared spectroscopy, Raman spectroscopy, and X-ray powder diffraction. Both X-ray powder diffraction and Raman spectroscopy suggests that fluorine-poor phlogopite decomposes earlier than the fluorine-rich phlogopite. Moreover, the O-H bonds and lattice modes are stiffer for the fluorine-rich phlogopite than the fluorine-poor phlogopite, which is well responsible for the mechanism of fluorine stabilizing phlogopite. Based on our studies, we propose that fluorine-rich phlogopite can effectively transport water and fluorine to the deep Earth.</p>

Methods for the Concentration of Bovine Ac-Globulin (Factor V)

1961 ◽  
Vol 06 (03) ◽  
pp. 435-444 ◽  
Author(s):  
Ricardo H. Landaburu ◽  
Walter H. Seegers
Keyword(s):  
Room Temperature ◽  
Barium Carbonate ◽  
Deae Cellulose ◽  
Reducing Agents ◽  
Factor V ◽  
Isoelectric Precipitation ◽  
Stabilizing Agent ◽  
Bovine Plasma ◽  
The Stability

SummaryAn attempt was made to obtain Ac-globulin from bovine plasma. The concentrates contain mostly protein, and phosphorus is also present. The stability characteristics vary from one preparation to another, but in general there was no loss before 1 month in a deep freeze or before 1 week in an icebox, or before 5 hours at room temperature. Reducing agents destroy the activity rapidly. S-acetylmercaptosuccinic anhydride is an effective stabilizing agent. Greatest stability was at pH 6.0.In the purification bovine plasma is adsorbed with barium carbonate and diluted 6-fold with water. Protein is removed at pH 6.0 and the Ac-globulin is precipitated at pH 5.0. Rivanol and alcohol fractionation is followed by chromatography on Amberlite IRC-50 or DEAE-cellulose. The final product is obtained by isoelectric precipitation.

A possibility of using nickel concentrate, obtained as a result of hydrometallurgical enrichment of manganese-containing raw materials, at steel alloying

2020 ◽  
Vol 76 (7) ◽  
pp. 709-715
Author(s):  
O. Yu. Kichigina
Keyword(s):  
Raw Materials ◽  
Experimental Studies ◽  
Selective Extraction ◽  
Technological Parameters ◽  
Nickel Iron ◽  
Nickel Recovery ◽  
Nickel Concentrate ◽  
Steel Alloying ◽  
High Degree ◽  
Comprehensive Processing

At production of stainless steel expensive alloying elements, containing nickel, are used. To decrease the steel cost, substitution of nickel during steel alloying process by its oxides is an actual task. Results of analysis of thermodynamic and experimental studies of nickel reducing from its oxide presented, as well as methods of nickel oxide obtaining at manganese bearing complex raw materials enrichment and practice of its application during steel alloying. Technology of comprehensive processing of complex manganese-containing raw materials considered, including leaching and selective extraction out of the solution valuable components: manganese, nickel, iron, cobalt and copper. Based on theoretical and experiment studies, a possibility of substitution of metal nickel by concentrates, obtained as a result of hydrometallurgical enrichment, was confirmed. Optimal technological parameters, ensuring high degree of nickel recovery out of the initial raw materials were determined. It was established, that for direct steel alloying it is reasonable to add into the charge pellets, consisting of nickel concentrate and coke fines, that enables to reach the through nickel recovery at a level of 90%. The proposed method of alloying steel by nickel gives a possibility to decrease considerably steel cost at the expense of application of nickel concentrate, obtained out of tails of hydrometallurgical enrichment of manganese-bearing raw materials, which is much cheaper comparing with the metal nickel.

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

The Role of Hydrophobicity in the Stability and pH-Switchability of (RXDX)4 and Coumarin-RXDX Conjugate β-Sheets

2020 ◽  
Author(s):  
Ryan Weber ◽  
Martin McCullagh
Keyword(s):  
Biological Imaging ◽  
Ph Sensing ◽  
Hydrophobic Residue ◽  
Ideal Candidate ◽  
Self Assembling ◽  
Sensing Applications ◽  
Β Sheets ◽  
The Stability ◽  
Dynamics Simulations

<p>pH-switchable, self-assembling materials are of interest in biological imaging and sensing applications. Here we propose that combining the pH-switchability of RXDX (X=Ala, Val, Leu, Ile, Phe) peptides and the optical properties of coumarin creates an ideal candidate for these materials. This suggestion is tested with a thorough set of all-atom molecular dynamics simulations. We first investigate the dependence of pH-switchabiliy on the identity of the hydrophobic residue, X, in the bare (RXDX)<sub>4</sub> systems. Increasing the hydrophobicity stabilizes the fiber which, in turn, reduces the pH-switchabilty of the system. This behavior is found to be somewhat transferable to systems in which a single hydrophobic residue is replaced with a coumarin containing amino acid. In this case, conjugates with X=Ala are found to be unstable and both pHs while conjugates with X=Val, Leu, Ile and Phe are found to form stable β-sheets at least at neutral pH. The (RFDF)<sub>4</sub>-coumarin conjugate is found to have the largest relative entropy value of 0.884 +/- 0.001 between neutral and acidic coumarin ordering distributions. Thus, we posit that coumarin-(RFDF)<sub>4</sub> containing peptide sequences are ideal candidates for pH-sensing bioelectronic materials.</p>

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