Oxidative hydrolysis of CsI radioaerosols localized on TRUMEM metallic membrane filter

2008 ◽  
Vol 50 (4) ◽  
pp. 402-407
Author(s):  
E. N. Bogachev ◽  
I. A. Rumer ◽  
S. A. Kulyukhin
Keyword(s):  
Membrane Filter ◽  
Hydrolysis Of ◽  
Metallic Membrane

Identification of acid-insoluble filter-plugging compounds and optimal acid-washing procedures for tubular backpulse pressure filters

TAPPI Journal ◽  
2011 ◽  
Vol 10 (1) ◽  
pp. 17-23
Author(s):  
KEVIN TAYLOR ◽  
RICH ADDERLY ◽  
GAVIN BAXTER
Keyword(s):  
Calcium Sulfate ◽  
Membrane Filter ◽  
Sulfamic Acid ◽  
Xrd Analysis ◽  
Metal Sulfides ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gypsum Formation ◽  
Acid Washing ◽  
Hydrolysis Of

Over time, performance of tubular backpulse pressure filters in kraft mills deteriorates, even with regular acid washing. Unscheduled filter replacement due to filter plugging results in significant costs and may result in mill downtime. We identified acid-insoluble filter-plugging materials by scanning electron microscope/energy-dispersion X-ray spectroscopy (SEM/EDS) and X-ray diffraction (XRD) analysis in both polypropylene and Gore-Tex™ membrane filter socks. The major filter-plugging components were calcium sulfate (gypsum), calcium phosphate (hydroxylapatite), aluminosilicate clays, metal sulfides, and carbon. We carried out detailed sample analysis of both the standard acid-washing procedure and a modified procedure. Filter plugging by gypsum and metal sulfides appeared to occur because of the acid-washing procedure. Gypsum formation on the filter resulted from significant hydrolysis of sulfamic acid solution at temperatures greater than 130°F. Modification of the acid-washing procedure greatly reduced the amount of gypsum and addition of a surfactant to the acid reduced wash time and mobilized some of the carbon from the filter. With surfactant, acid washing was 95% complete after 40 min.

Filtration of Pulp of Complex Processing of Iron-Nickel Concentrate – a Waste Product of Magnesium Oxide Production

2019 ◽  
Vol 23 (10) ◽  
pp. 24-28 ◽  
Author(s):  
N.L. Mokhireva ◽  
V.R. Mirolyubov
Keyword(s):  
Membrane Filter ◽  
Waste Product ◽  
Filter Press ◽  
Processing Plant ◽  
Nickel Concentrate ◽  
Iron Salts ◽  
Washing Process ◽  
Iron Nickel ◽  
Granulometric Characteristics ◽  
Hydrolysis Of

The granulometric characteristics of the precipitate were investigated, and the chemical composition of the solution for complex processing of iron-nickel concentrate was established. The filtering process was carried out using a model of a chamber and chamber-membrane filter press. Separation of the suspension was implemented using chambers with a depth of 10 and 20 mm. It was established that washing is possible only with the use of a weak HCl solution due to the need to inhibit the development of hydrolysis of iron salts in the pores of the sediment. A scheme for optimizing the water balance of the washing process is proposed. Initial data are formulated for designing a filtration section of a complex processing plant for iron-nickel concentrate. Criteria for process automation are defined.

Equilibrium hydrogen fluoride pressures over metal hydrofluorides, fluorophosphates and metal difluoride systems

1983 ◽  
Vol 36 (4) ◽  
pp. 649 ◽  
Author(s):  
GA Bottomley ◽  
JB Farrow ◽  
FJ Lincoln
Keyword(s):  
Hydrogen Fluoride ◽  
Pressure Range ◽  
Membrane Filter ◽  
Thermodynamic Quantities ◽  
Reaction Enthalpy ◽  
Nitrogen Gas ◽  
Sodium Potassium ◽  
Reciprocal Temperature ◽  
Filter Papers ◽  
Hydrolysis Of

The equilibrium pressures of hydrogen fluoride gas over barium, sodium, potassium and caesium monohydrofluorides have been measured in the general pressure range from 0.01 Pa to 1000 Pa. Nitrogen gas is transported through the powdered solid, then the acquired HF gas is absorbed on membrane filter papers for subsequent analysis with a fluoride ion specific electrode. By similarly using nitrogen with water vapour the equilibrium hydrogen fluoride pressures generated by the hydrolysis of sodium, potassium, barium and lead monofluorophosphates, and zinc, lead and cobalt difluorides were studied. The results for all systems are represented by linear logKp against reciprocal temperature equations from which, where the corresponding chemical reaction has been identified with considerable certainty, the reaction enthalpy, entropy and other thermodynamic quantities have been deduced.

Fine Structural Localization of Acyltransferases Involved in Lipid Synthesis in Intestinal Mucosa.

1970 ◽  
Vol 28 ◽  
pp. 54-55
Author(s):  
R. J. Barrnett ◽  
J. A. Higgins
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Lipid Synthesis ◽  
Mucosal Cell ◽  
Structural Localization ◽  
Morphological Studies ◽  
Mucosal Cells ◽  
Initial Appearance ◽  
Sh Group ◽  
Hydrolysis Of ◽  
Intestinal Mucosal Cells

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

Elucidating cyclic AMP signaling in subcellular domains with optogenetic tools and fluorescent biosensors

2019 ◽  
Vol 47 (6) ◽  
pp. 1733-1747 ◽  
Author(s):  
Christina Klausen ◽  
Fabian Kaiser ◽  
Birthe Stüven ◽  
Jan N. Hansen ◽  
Dagmar Wachten
Keyword(s):  
Cyclic Amp ◽  
Adenosine Monophosphate ◽  
Adenylyl Cyclases ◽  
Temporal Precision ◽  
Fluorescent Biosensors ◽  
Subcellular Domains ◽  
Spatio Temporal ◽  
Hydrolysis Of ◽  
Shed Light ◽  
Cyclic Amp Signaling

The second messenger 3′,5′-cyclic nucleoside adenosine monophosphate (cAMP) plays a key role in signal transduction across prokaryotes and eukaryotes. Cyclic AMP signaling is compartmentalized into microdomains to fulfil specific functions. To define the function of cAMP within these microdomains, signaling needs to be analyzed with spatio-temporal precision. To this end, optogenetic approaches and genetically encoded fluorescent biosensors are particularly well suited. Synthesis and hydrolysis of cAMP can be directly manipulated by photoactivated adenylyl cyclases (PACs) and light-regulated phosphodiesterases (PDEs), respectively. In addition, many biosensors have been designed to spatially and temporarily resolve cAMP dynamics in the cell. This review provides an overview about optogenetic tools and biosensors to shed light on the subcellular organization of cAMP signaling.

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