SYNTHESES OF CATION EXCHANGER WITH MACROPOROSITY AND INVESTIGATING SPECIFIC PROPERTIES

2020 ◽  
Vol 5 (443) ◽  
pp. 108-115
Author(s):  
Shokhakimova Aziza Alimdjanovna, ◽  
◽  
Turabdzhanov Sadritdin Maxamatdinovich, ◽  
Kedelbayev Bakhitjan Shilmirzaevich, ◽  
Peter Lieberzeit, ◽  
...  
Keyword(s):  
Polymer Matrix ◽  
High Speed ◽  
Cation Exchanger ◽  
Total Pore Volume ◽  
Molar Ratio ◽  
Small Radius ◽  
Macroporous Structure ◽  
Ion Exchangers ◽  
Optimal Amount ◽  
Acid Cation

Obtained new strongly acid cation exchanger of macroporous structure based on furfural and dipheniloxide. The optimal amount of the poreformed agent and the molar ratio of the reacting substances were determined. Initially results showed that the polymer matrix using camphor as pore forming agent present a uniform surface with inter-connected pores and adding camphor into the polymer matrix could attain more abundant pores than adding n-heptane. We studied the components, surface and pore structures of the сation exchanger by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). SEM observations showed that the resin abounded in macropores as large as 7.4 to 22.6 µm both in the surface and the interior. The parameters of the porous structure of the samples are calculated using by equation BET (Brauner., at al.) and the total pore volume of ion exchangers and the radius of submicroscopic capillaries were determined. Finally dates testing prototypes under application conditions, allow us to recommend this cation exchanger for sorption of small radius ions at high speed, as fundamentals upon receipt of ion exchangers, etc.

Study on the Synthesis of Isoamyl Acetate Catalyzed by Strong Acidic Cation Exchange Resin

2011 ◽  
Vol 396-398 ◽  
pp. 2411-2415 ◽  
Author(s):  
Ping Lan ◽  
Li Hong Lan ◽  
Tao Xie ◽  
An Ping Liao
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Cation Exchanger ◽  
Cation Exchange Resin ◽  
Isoamyl Acetate ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Reaction Conditions ◽  
Optimum Reaction

Isoamyl acetate was synthesized from isoamylol and glacial acetic acid with strong acidic cation exchanger as catalyst. The effects of reaction conditions such as acid-alcohol ratio, reaction time, catalyst dosage to esterification reaction have been investigated and the optimum reaction conditions can be concluded as: the molar ratio of acetic acid to isoamylol 0.8:1, reaction time 2h, 25 % of catalyst (quality of acetic acid as benchmark). The conversion rate can reach up to 75.46%. The catalytic ability didn’t reduce significantly after reusing 10 times and the results showed that the catalyst exhibited preferably catalytic activity and reusability.

scholarly journals Sorption Extraction of Rare Earth Metals from Wet-Process Phosphoric Acid

2021 ◽  
Vol 83 (1) ◽  
pp. 140-152
Author(s):  
Baltabekova Zhazira ◽  
Kenzhaliyev Bagdaulet ◽  
Lokhova Nina ◽  
Kassymzhanov Kaisar
Keyword(s):  
Rare Earth ◽  
Phosphoric Acid ◽  
Treatment Process ◽  
Cation Exchanger ◽  
Rare Earth Metals ◽  
Ion Exchangers ◽  
Technological Parameters ◽  
Complex Composition ◽  
Impurity Composition ◽  
Wet Process

When apatites and phosphorites are processed, up to 30% of rare earth metals are converted into wet-process phosphoric acid. Wet-process phosphoric acid from the phosphorite treatment process differs from apatite one by impurity composition, i.e. the iron content is by 3.5 times, and calcium is by 5.0 times more. The complex composition of the wet-process phosphoric acid from the phosphorite treatment process requires additional researches to select optimal ion exchangers and technological parameters of sorption. Various aspects of sorption have been studied to select the optimal ion exchangers and technological parameters, and technological modes for desorption of rare earth metals from a cation exchanger to obtain a concentrate of rare earth metals have been completed. The method enables to extract rare earth metals without changing the composition of commercial wet-process phosphoric acid directly in the production process of the enterprises engaged in the phosphorite treatment process.

Influence of the Composition of the Sulfuric Acid Cation Exchanger on the Efficiency of Chromatographic Purification of Petroleum Vanadyl Porphyrins

2020 ◽  
Vol 93 (6) ◽  
pp. 888-896
Author(s):  
N. A. Mironov ◽  
D. V. Milordov ◽  
E. G. Tazeeva ◽  
G. R. Abilova ◽  
D. I. Tazeev ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Cation Exchanger ◽  
Chromatographic Purification ◽  
Acid Cation

Resorcinol-Formaldehyde Resins for Cesium Removal from Solutions Produced after Processing Spent Ion-Exchangers

2020 ◽  
Vol 842 ◽  
pp. 107-114
Author(s):  
Eduard Tokar' ◽  
Marina Palamarchuk ◽  
Mikhail Tutov ◽  
Anna Matskevich ◽  
Andrei Egorin
Keyword(s):  
Chemical Stability ◽  
Contact Time ◽  
Sorption Properties ◽  
Molar Ratio ◽  
Ion Exchangers ◽  
Resorcinol Formaldehyde ◽  
Dynamic Conditions ◽  
Cesium Removal ◽  
Dynamic Sorption ◽  
Short Contact Time

A series of resorcinol-formaldehyde resins (RFR) has been prepared and studied in terms of Cs-137 uptake efficiency from solutions (0.75М NaOH-2.25M NaNO3) intended for processing spent ion-exchangers. Sample synthesized at molar ratio of resorcinol to formaldehyde of 1.8:2.2 and solidified at 210 °C (sample RFR-3-1-210) has shown the best sorption-selective performance and chemical stability. Implementing RFR in dynamic sorption scheme enables to reduce its decay due to short contact time. In dynamic conditions, after feeding 1000 bed volumes of the solution, RFR 3-1-210 maintains its sorption properties after 6 sorption-desorption cycles.

Automatic Flaw Detector Channels Sensitivity Adjustment with the Use of an Adaptive Threshold

NDT World ◽  
2016 ◽  
Vol 19 (3) ◽  
pp. 77-80
Author(s):  
Кисляковский ◽  
Oleg Kislyakovsky ◽  
Чистякова ◽  
Olga Chistyakova ◽  
Тарабрин ◽  
...  
Keyword(s):  
High Speed ◽  
Dynamic Range ◽  
Optimal Algorithm ◽  
Diagnostic System ◽  
Adaptive Threshold ◽  
Flaw Detector ◽  
Small Radius ◽  
Maximum Information ◽  
High Level ◽  
The Impact

Introduction. With high-speed total ultrasonic testing (UT) of the rails, the urgent task is to provide the required testing sensitivity under the impact of a significant number of adverse factors caused by the following reasons:  unstable acoustic contact;  incorrect flaw detector channel settings due to underskilled staff;  a misalignment, for example when passing a small radius curve or when rails have significant lateral wear. The listed factors lead to level changing of echo signals within a wide dynamic range as well as to echo amplitudes ratio changing of useful and noise signals. In contrast to manual testing when an operator has the possibility of multiple scanning, total rails testing by a mobile diagnostic system is fulfilled by only a single scan. The objective of the work was to develop an optimal algorithm of flaw detector channels sensitivity adjustment and formulate the reasonable requirements for a mathematical model and hardware. Method. Theoretical researches and experimental work were conducted and resulted in the development of a multichannel flaw detector for inspection of rails by mobile means. The analysis of different mathematical models has enabled the optimal algorithm for automatic channels sensitivity adjustment to be developed. Results. The developed algorithm has allowed minimizing the impact of the negative factors and compensating the sensitivity to the level that enables high-speed single-scan rails testing to be fulfilled and maximum information at a high level of reliability to be recorded. Implementation of the adaptive threshold principle has made it possible to develop and offer the technique and technology for automatic flaw detector channels sensitivity adjustment. Conclusion. The offered technique and technology can be fully put into practice with the developed flaw detector and its control software.

scholarly journals Grip and limb force limits to turning performance in competition horses

2010 ◽  
Vol 278 (1715) ◽  
pp. 2105-2111 ◽  
Author(s):  
Huiling Tan ◽  
Alan M. Wilson
Keyword(s):  
Angular Velocity ◽  
High Speed ◽  
Small Radius ◽  
Maximum Speed ◽  
Large Radius ◽  
Centripetal Acceleration ◽  
Straight Line ◽  
Prey Interaction ◽  
The Coefficient Of Friction ◽  
Stride Parameters

Manoeuverability is a key requirement for successful terrestrial locomotion, especially on variable terrain, and is a deciding factor in predator–prey interaction. Compared with straight-line running, bend running requires additional leg force to generate centripetal acceleration. In humans, this results in a reduction in maximum speed during bend running and a published model assuming maximum limb force as a constraint accurately predicts how much a sprinter must slow down on a bend given his maximum straight-line speed. In contrast, greyhounds do not slow down or change stride parameters during bend running, which suggests that their limbs can apply the additional force for this manoeuvre. We collected horizontal speed and angular velocity of heading of horses while they turned in different scenarios during competitive polo and horse racing. The data were used to evaluate the limits of turning performance. During high-speed turns of large radius horizontal speed was lower on the bend, as would be predicted from a model assuming a limb force limit to running speed. During small radius turns the angular velocity of heading decreased with increasing speed in a manner consistent with the coefficient of friction of the hoof–surface interaction setting the limit to centripetal force to avoid slipping.

scholarly journals COMPARATIVE ANALYSIS OF MAMMALIAN SPERM MOTILITY

1972 ◽  
Vol 53 (2) ◽  
pp. 561-573 ◽  
Author(s):  
David M. Phillips
Keyword(s):  
High Speed ◽  
Mammalian Species ◽  
Chinese Hamster ◽  
Small Radius ◽  
Radius Of Curvature ◽  
Large Radius ◽  
Cross Sectional ◽  
Mammalian Sperm ◽  
High Speed Cinematography ◽  
Pass Through

Spermatozoa of several mammalian species were studied by means of high-speed cinematography and electron microscopy. Three types of motile patterns were observed in mouse spermatozoa. The first type involved an asymmetrical beat which seemed to propel the sperm in circular paths. The second type involved rotation of the sperm and appeared to allow them to maintain straight paths. In the third type of pattern, the sperm appeared to move by crawling on surfaces in a snakelike manner. Spermatozoa of rabbit and Chinese hamster also had an asymmetrical beat which sometimes caused them to swim in circles. In spite of the asymmetry of the beat, these spermatozoa were also able to swim in straight paths by rotating around a central axis as they swam. Spermatozoa of some species appeared very flexible; their flagella formed arcs with a very small radius of curvature as they beat. Spermatozoa of other species appeared very stiff, and their flagella formed arcs with a very large radius of curvature. The stiffness of the spermatozoan appeared to correlate positively with the cross-sectional area of the dense fibers. This suggests that the dense fibers may be stiff elastic elements. Opossum sperm become paired as they pass through the epididymis. Pairs of opossum spermatozoa beat in a coordinated, alternating manner.

Sign in / Sign up

Export Citation Format

Share Document