Autogenous sealing of a cavity in bentonite clay: observation by X-ray computerized tomography

✓ A patient with an anterior sacral meningocele combined with a hamartoma was diagnosed with x-ray films, myelography, and computerized tomography. She was successfully operated on by a transabdominal approach.

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Computerized Tomography: A Perspective in the Pediatric Patient

PEDIATRICS ◽

10.1542/peds.59.2.305 ◽

1977 ◽

Vol 59 (2) ◽

pp. 305-308

Author(s):

Derek Harwood-Nash ◽

Herman Grossman ◽

Alvin Felman ◽

John Kirkpatrick ◽

Leonard Swischuk

Keyword(s):

Computerized Tomography ◽

Soft Tissues ◽

Conventional Radiography ◽

The United States ◽

The Body ◽

Whole Body ◽

Central Research ◽

X Ray ◽

Whole Body Ct

Computerized tomography (CT), a technique conceptualized by Oldendorf in 19611 and developed by Hounsfield2 of EMI-Tronics Inc. (EMI) Central Research Laboratories, has proven to be a successful innovation in neuroradiology. Reviews by Ambrose3 in England and by Baker et al.4 and by New et al.5 in the United States have clearly demonstrated the value of this new modality in neuroradiological diagnosis. In 1975 Houser et al.6 and Harwood-Nash et al.7 provided the initial clinical and radiological data about CT in infants and children. More recently this technique has been extended to the study of tissues and organs in the body other than those in the head. This has been accomplished by modification of the original machine into a whole-body CT system. Early reviews by Ledley et al.8 and by Alfidi et al.9 suggest a significant potential for diagnosis of lesions in the abdomen, pelvis, and thorax. The advantages of CT are that it is less invasive than standard special diagnostic radiological procedures and that for the first time it provides in vivo information regarding the content and the characteristics of tissue composing organs and masses. DESCRIPTION OF EQUIPMENT In conventional radiography an image is made on radiographic film by an attenuated X-ray beam. In passing through a core of tissue, each ray of the beam is attenuated as it is absorbed and scattered by the tissue in its path. The intensity of the transmitted ray depends on the sum total of X-ray attenuation by all the different soft tissues in its path.

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Influence of Organophilization Process Variables in Bentonite Clays from Cubati-PB

Materials Science Forum ◽

10.4028/www.scientific.net/msf.727-728.1467 ◽

2012 ◽

Vol 727-728 ◽

pp. 1467-1472

Author(s):

Carla Dantas da Silva ◽

Rosa do Carmo de Oliveira Lima ◽

Julliana Marques Rocha Costa ◽

Gelmires Araújo Neves ◽

Heber Carlos Ferreira

Keyword(s):

Thermogravimetric Analysis ◽

Bentonite Clay ◽

Laser Diffraction ◽

Ionic Surfactants ◽

Organic Media ◽

Process Variables ◽

X Ray Diffraction ◽

X Ray ◽

Bentonite Clays ◽

Sodium Form

This work aims at the development of organoclay from two varieties of bentonite for use in organic media using ionic surfactants, studying the influence of process variables in the organophilization process. We used the following materials: natural bentonite clay from Cubati-PB District, and the ionic quaternary ammonium salt: Praepagen WB® with 45% active matter. The clays were benefited and then turned into sodium form and subsequently into organoclays. The bentonites were characterized by laser diffraction (GA) X-ray fluorescence chemical composition (EDX), thermogravimetric analysis (TGA), thermogravimetry (DTA) and X-ray diffraction (XRD). The organoclays were characterized by (XRD) thermogravimetric analysis (TGA) and thermogravimetry (DTA). The results showed that the clay has potential for application in the organophilization process and that there is influence of process variables.

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The effects of fine grinding on the physicochemical properties and thermal behavior of bentonite clay

Journal of the Serbian Chemical Society ◽

10.2298/jsc0211753f ◽

2002 ◽

Vol 67 (11) ◽

pp. 753-760 ◽

Cited By ~ 11

Author(s):

Leposava Filipovic-Petrovic ◽

Ljiljana Kostic-Gvozdenovic ◽

Stanka Eric-Antonic

Keyword(s):

Mechanical Treatment ◽

Structural Changes ◽

Bentonite Clay ◽

Powdered Material ◽

X Ray Diffraction ◽

X Ray ◽

Fine Grinding ◽

Dta Analysis ◽

Processing Steps ◽

Vibration Mill

In this study, the results obtained by the mechanical treatment of bentonite clay Zavidinci, Serbia in a laboratory vibration mill with rings for different periods of time are presented. The successive structural changes of the minerals were studied by X-ray diffraction analysis, DTA analysis, IR spectroscopy and particle size distribution. The reactivity changes were controlled by CEC. The starting material and the material mechanically treated for 30 min were sintered at several temperature and for different time periods examined by X-ray diffraction. Mechanical treatment by fine grinding of bentonite clay produces structural changes of the powdered material and influences its behavior in further processing steps in particular after thermal treatment.

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Measurement Method of X-ray Focus Projection Coordinates of Three-Dimensional Micro-Computerized Tomography Scanning System

Acta Optica Sinica ◽

10.3788/aos20092905.1275 ◽

2009 ◽

Vol 29 (5) ◽

pp. 1275-1280

Author(s):

杨民 Yang Min ◽

刘静华 Liu Jinghua ◽

李保磊 Li Baolei ◽

吴文晋 Wu Wenjin ◽

王钢 Wang Gang

Keyword(s):

Computerized Tomography ◽

Measurement Method ◽

Three Dimensional ◽

Scanning System ◽

X Ray ◽

Tomography Scanning ◽

Focus Projection

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Studies of new occurrences of bentonite clays in the State of Paraíba for use in water based drilling fluids

Rem Revista Escola de Minas ◽

10.1590/s0370-44672013000400013 ◽

2013 ◽

Vol 66 (4) ◽

pp. 485-491 ◽

Cited By ~ 7

Author(s):

Isabelle A. Silva ◽

Julliana Marques R. Costa ◽

Romualdo R. Menezes ◽

Heber S. Ferreira ◽

Gelmires de A. Neves ◽

...

Keyword(s):

Bentonite Clay ◽

Particle Size Analysis ◽

The State ◽

Size Analysis ◽

Drilling Fluids ◽

X Ray ◽

Clay Deposits ◽

Water Based ◽

Bentonite Clays ◽

New Occurrences

New bentonite clay deposits have recently been discovered in the state of Paraíba, mainly in the municipalities of Cubati and Pedra Lavrada, creating great expectations in view of the possibility of expanding industrial production using these new reserves. The aim of this study was to study the new occurrences of bentonite clay in Paraíba, particularly in the municipality of Pedra Lavrada, for use in water based drilling fluids. The mineralogical properties of the clays were characterized by particle size analysis using laser diffraction, and thermogravimetric and differential thermal analysis, and its chemical composition was analyzed by X-ray fluorescence, X-ray diffraction, cation exchange capacity and specific surface area. The bentonite clays were treated with sodium carbonate at concentrations of 75, 100, 125, 150 and 175mEq/100g of dry clay, to transform them from polycationic to sodium form. For the technological characterization, drilling fluids were prepared according to the standards of Petrobras. The results indicated that the mineralogical composition of the samples consisted of montmorillonite, kaolinite and quartz. As for their rheological properties, the samples were found to partially meet the rheological requirements of the Petrobras standard.

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