An experimental study on barium peritonitis in rats

International Nuclear Information System (INIS)

Kang, Heung Sik; Han, Man Chung; Kim, Chu Wan

1985-01-01

Barium sulfate is universally used contrast media in gastrointestinal roentgenology, and spillage of barium into peritoneal cavity can occur. The references on effect of barium sulfate in the peritoneal cavity have been scattered and the results are varied. In 80 rats, body weight of 130 gm to 150 gm, sterile pure barium, sterile commercial barium, intestinal content, and mixed pure barium and intestinal content were experimentally injected into the peritoneal cavity. Consecutive weekly laparotomy and microscopic examination were done for 4 weeks. The results are as followings: 1. Mind inflammatory reaction and mild adhesion after sterile pure barium injection. 2. Mild inflammatory reaction and moderate adhesion after sterile commercial barium injection. 3. Acute peritonitis and abscess formation after intestinal content injection. 4. High mortality due to severe acute peritonitis, and severe adhesion in survivors after injection of both pure barium and intestinal content.

Barium carbonate as an agent to improve the electrical properties of neodymium-barium-copper system at high temperature

Energy Technology Data Exchange (ETDEWEB)

Fernandes, J.P. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Duarte, G.W. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Research Group in Technology and Information, Centro Universitário Barriga Verde (UNIBAVE), Santa Catarina, SC (Brazil); Caldart, C. [Post-Graduate Program in Science and Materials Engineering, Universidade do Extremo Sul Catarinense (UNESC), Criciúma, SC, 88806-000 (Brazil); Kniess, C.T. [Post-Graduate Program in Professional Master in Management, Universidade Nove de Julho, São Paulo, SP (Brazil); Montedo, O.R.K.; Rocha, M.R. [Post-Graduate Program in Science and Materials Engineering, Universidade do Extremo Sul Catarinense (UNESC), Criciúma, SC, 88806-000 (Brazil); Riella, H.G. [Post-Graduate Program in Chemical Engineering, Universidade Federal de Santa Catarina (UFSC), Florianópolis, SC, 88040-900 (Brazil); Fiori, M.A., E-mail: fiori@unochapeco.edu.br [Post-Graduate Program in Environmental Science, Universidade Comunitária da Região de Chapecó (UNOCHAPECÓ), Chapecó, SC, 89809-000 (Brazil); Post-Graduate Program in Technology and Management of the Innovation, Universidade Comunitária da Região de Chapecó (UNOCHAPECÓ), Chapecó, SC, 89809-000 (Brazil)

2015-11-15

Specialized ceramics are manufactured under special conditions and contain specific elements. They possess unique electrical and thermal properties and are frequently used by the electronics industry. Ceramics containing neodymium-barium-copper (NBC) exhibit high conductivities at low temperatures. NBC-based ceramics are typically combined with oxides, i.e., NBCo produced from neodymium oxide, barium oxide and copper oxide. This study presents NBC ceramics that were produced with barium carbonate, copper oxide and neodymium oxide (NBCa) as starting materials. These ceramics have good electrical conductivities at room temperature. Their conductivities are temperature dependent and related to the starting amount of barium carbonate (w%). - Highlights: • The new crystalline structure were obtained due presence of the barium carbonate. • The NBCa compound has excellent electrical conductivity at room temperature. • The grain crystalline morphology was modified by presence of the barium carbonate. • New Phases α and β were introduced by carbonate barium in the NBC compound.

Barium carbonate as an agent to improve the electrical properties of neodymium-barium-copper system at high temperature

International Nuclear Information System (INIS)

Fernandes, J.P.; Duarte, G.W.; Caldart, C.; Kniess, C.T.; Montedo, O.R.K.; Rocha, M.R.; Riella, H.G.; Fiori, M.A.

2015-01-01

Specialized ceramics are manufactured under special conditions and contain specific elements. They possess unique electrical and thermal properties and are frequently used by the electronics industry. Ceramics containing neodymium-barium-copper (NBC) exhibit high conductivities at low temperatures. NBC-based ceramics are typically combined with oxides, i.e., NBCo produced from neodymium oxide, barium oxide and copper oxide. This study presents NBC ceramics that were produced with barium carbonate, copper oxide and neodymium oxide (NBCa) as starting materials. These ceramics have good electrical conductivities at room temperature. Their conductivities are temperature dependent and related to the starting amount of barium carbonate (w%). - Highlights: • The new crystalline structure were obtained due presence of the barium carbonate. • The NBCa compound has excellent electrical conductivity at room temperature. • The grain crystalline morphology was modified by presence of the barium carbonate. • New Phases α and β were introduced by carbonate barium in the NBC compound

Barium aspiration and alveolarisation of barium in an infant: A case report and review of management

Directory of Open Access Journals (Sweden)

Alan F. Isles

2014-05-01

Full Text Available We describe a case of bilateral inhalation and alveolarisation of barium in an infant following a barium swallow for investigation of dusky spells associated with feeds. A bronchoscopy subsequently revealed the presence of a mid-tracheal tracheo-oesophageal cleft. We review the literature on barium aspiration, its consequences and make recommendations for management.

Statistical properties of barium stars

International Nuclear Information System (INIS)

Hakkila, J.E.

1986-01-01

Barium stars are G- and K-giant stars with atmospheric excesses of s-process elements, and a broadband spectral depression in the blue portion of the spectrum. The strength of the λ4554 Ball line is used as a classification parameter known as the Barium Intensity. They have a mean absolute magnitude of 1.0 and a dispersion of 1.2 magnitudes (assuming a Gaussian distribution in absolute magnitude) as measured from secular and statistical parallaxes. These stars apparently belong to a young-disk population from analyses of both the solar reflex motion and their residual velocity distribution, which implies that they have an upper mass limit of around three solar masses. There is no apparent correlation of barium intensity with either luminosity or kinematic properties. The barium stars appear to be preferentially distributed in the direction of the local spiral arm, but show no preference to associate with or avoid the direction of the galactic center. They do not appear related to either the carbon or S-stars because of these tendencies and because of the stellar population to which each type of star belongs. The distribution in absolute magnitude combined with star count analyses implies that these stars are slightly less numerous than previously believed. Barium stars show infrared excesses that correlate with their barium intensities

Barium sulfate aspiration: Severe chemical pneumonia induced by a massive reflux of contrast medium during small bowel barium enema.

Science.gov (United States)

Zhang, Lin; Yang, Yi; Zhang, Ji; Zhou, Xiaowei; Dong, Hongmei; Zhou, Yiwu

2015-08-01

Barium contrast radiography is a conventional procedure aimed at revealing lesions of the alimentary tract using barium sulfate on X-ray irradiation. Although it is widely used in clinics, adverse effects and complications are observed, such as anaphylaxis, granuloma, fecalithes, abdomen-leaking, embolism, bacterial contamination, and aspiration. We report a case of death due to a massive barium sulfate aspiration resulted from an air-barium double contrast enema radiography. A 25-year-old female patient was hospitalized with symptoms of abdominal distention, nausea, vomiting and diarrhea for three days. A progressive respiratory distress presented only 1h after a small bowel air-barium double contrast enema. The patient died 11h later. The result of autopsy revealed the cause of death to be severe chemical pneumonitis induced by gastric fluid which was aspirated into her lungs. Barium sulfate is generally recognized to be chemically inert for the respiratory system, but a mixture of barium sulfate with gastric contents is fatal. Here we intend to suggest that, when determining the potential cause of death, medical examiners should consider a patient's status quo as well as the possible adverse effects and complications caused by the barium sulfate preparation during gastrointestinal radiography. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Bacterial Reduction Of Barium Sulphate By Sulphate-Reducing Bacteria

Directory of Open Access Journals (Sweden)

Luptáková Alena

2015-12-01

Full Text Available Acid mine drainage (AMD is a worldwide problem leading to contamination of water sources. AMD are characterized by low pH and high content of heavy metals and sulphates. The barium salts application presents one of the methods for the sulphates removing from AMD. Barium chloride, barium hydroxide and barium sulphide are used for the sulphates precipitation in the form of barium sulphate. Because of high investment costs of barium salts, barium sulphide is recycled from barium sulphate precipitates. It can be recycled by thermic or bacterial reduction of barium sulphate. The aim of our study was to verify experimentally the possibility of the bacterial transformation of BaSO4 to BaS by sulphate-reducing bacteria. Applied BaSO4 came from experiments of sulphates removal from Smolnik AMD using BaCl2.

Barium aluminate cement: its application

International Nuclear Information System (INIS)

Drozdz, M.; Wolek, W.

1975-01-01

The technology of manufacturing barium aluminate cement from barium sulfate and alumina, using a rotary kiln for firing the clinker is described. The method of granulation of the homogenized charge was used. Conditions of using the ''to mud'' method in industry were indicated. The physical and chemical properties of barium aluminate cement are determined and the quality of several batches of cement prepared on a semi-industrial scale and their suitability for making highly refractory concretes are tested. The optimal composition of the concretes is determined as a function of the mixing water and barium aluminate cement contents. Several experimental batches of concretes were used in the linings of furnaces in the steel industry. The suitability of these cements for use in fields other than steelmaking is examined. It is established that calcium aluminate cement has certain limited applications [fr

Analysis of barium by isotope mass spectrometry

International Nuclear Information System (INIS)

Long Kaiming; Jia Baoting; Liu Xuemei

2004-01-01

The isotopic abundance ratios for barium at sub-microgram level are analyzed by thermal surface ionization mass spectrometry (TIMS). Rhenium trips used for sample preparation are firstly treated to eliminate possible barium background interference. During the preparation of barium samples phosphoric acid is added as an emitting and stabilizing reagent. The addition of phosphoric acid increases the collection efficiency and ion current strength and stability for barium. A relative standard deviation of 0.02% for the isotopic abundance ratio of 137 Ba to 138 Ba is achieved when the 138 Ba ion current is (1-3) x 10 -12 A. The experimental results also demonstrate that the isotope fractionation effect is negligibly small in the isotopic analysis of barium

Oesophageal motility disorders - diagnosis with a barium-rice study

International Nuclear Information System (INIS)

Schwickert, H.C.; Schadmand-Fischer, S.; Klose, P.; Staritz, M.; Ueberschaer, B.; Thelen, M.

1993-01-01

The purpose of this study was to evaluate the role of a 'barium-rice' study for diagnosis of dysphagia and oesophageal motility disorders. Material and methods: 203 patients with oesophageal motility disorders of various aetiologies were examined by both conventional barium study and a 'barium-rice' study. During the latter, oesophageal clearance of a defined mixture of barium sulfate and boiled rice was measured. Results: The conventional barium study revealed prolonged transit time in only 15.8% (32 of 203 cases), whereas barium-rice study was pathological in 50.8% (103 of 203 cases). In 71 of 171 patients (41.5%) with a normal barium study, barium-rice passage was prolonged. In 23 patients, radiological results were confirmed by manometric measurements. Conclusion: Oesophageal motility disorders are detected by a barim-rice study with high sensitivity independent of the underlying disease. The barium-rice study offers a simple diagnostic tool revealing quantitative and reliable results. The barium-rice study is a suitable method for screening and follow-up of patients with dysphagia and oesophageal motility disorders. (orig.) [de

Effect of sodium bicarbonate pretreatment on barium coating of mucosa during double contrast barium meal

International Nuclear Information System (INIS)

Kinnunen, J.; Toetterman, S.; Kaila, R.; Pietilae, J.; Linden, H.; Tervahartiala, P.

1983-01-01

The radiographic pattern of the areae gastricae is produced by barium lying in the intersecting furrows of the gastric mucosal surface. However, if the mucus layer on the gastric mucosa is thick, it interferes with the barium coating of the areae gastricae during double contrast barium meal. As sodium bicarbonate decreases the viscosity of mucus and thus may make the gastric mucus layer thinner, it was evaluated as a pretreatment agent in a routine double contrast upper-gastrointestinal study to improve the visualization of the areae gastricae. In a single blind study, 53 of 106 patients took sodium bicarbonate water mixtures at bedtime the day before and on the morning of the examination. According to the results of the present study mucolysis induced by the used doses of sodium bicarbonate does not significantly affect micromucosal visualization during double-contrast barium meal. (orig.) [de

Effect of sodium bicarbonate pretreatment on barium coating of mucosa during double contrast barium meal

Energy Technology Data Exchange (ETDEWEB)

Kinnunen, J.; Toetterman, S.; Kaila, R.; Pietilae, J.; Linden, H.; Tervahartiala, P.

1983-08-01

The radiographic pattern of the areae gastricae is produced by barium lying in the intersecting furrows of the gastric mucosal surface. However, if the mucus layer on the gastric mucosa is thick, it interferes with the barium coating of the areae gastricae during double contrast barium meal. As sodium bicarbonate decreases the viscosity of mucus and thus may make the gastric mucus layer thinner, it was evaluated as a pretreatment agent in a routine double contrast upper-gastrointestinal study to improve the visualization of the areae gastricae. In a single blind study, 53 of 106 patients took sodium bicarbonate water mixtures at bedtime the day before and on the morning of the examination. According to the results of the present study mucolysis induced by the used doses of sodium bicarbonate does not significantly affect micromucosal visualization during double-contrast barium meal.

Aspiration of Barium Contrast

Directory of Open Access Journals (Sweden)

Cristina Fuentes Santos

2014-01-01

Full Text Available The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical file was reviewed, images were found of a barium swallow study that the patient had undergone months earlier, and we were able to observe the exact moment of the aspiration of the contrast material. The patient had been asymptomatic since the test.

Binding and leakage of barium in alginate microbeads.

Science.gov (United States)

Mørch, Yrr A; Qi, Meirigeng; Gundersen, Per Ole M; Formo, Kjetil; Lacik, Igor; Skjåk-Braek, Gudmund; Oberholzer, Jose; Strand, Berit L

2012-11-01

Microbeads of alginate crosslinked with Ca(2+) and/or Ba(2+) are popular matrices in cell-based therapy. The aim of this study was to quantify the binding of barium in alginate microbeads and its leakage under in vitro and accumulation under in vivo conditions. Low concentrations of barium (1 mM) in combination with calcium (50 mM) and high concentrations of barium (20 mM) in gelling solutions were used for preparation of microbeads made of high-G and high-M alginates. High-G microbeads accumulated barium from gelling solution and contained higher concentrations of divalent ions for both low- and high-Ba exposure compared with high-G microbeads exposed to calcium solely and to high-M microbeads for all gelling conditions. Although most of the unbound divalent ions were removed during the wash and culture steps, leakage of barium was still detected during storage. Barium accumulation in blood and femur bone of mice implanted with high-G beads was found to be dose-dependent. Estimated barium leakage relevant to transplantation to diabetic patients with islets in alginate microbeads showed that the leakage was 2.5 times lower than the tolerable intake value given by WHO for high-G microbeads made using low barium concentration. The similar estimate gave 1.5 times higher than is the tolerable intake value for the high-G microbeads made using high barium concentration. To reduce the risk of barium accumulation that may be of safety concern, the microbeads made of high-G alginate gelled with a combination of calcium and low concentration of barium ions is recommended for islet transplantation. Copyright © 2012 Wiley Periodicals, Inc.

Anastomotic stenosis of the descending colon caused by barium granuloma formation following barium peritonitis: report of a case.

Science.gov (United States)

Kitajima, Toshihiro; Tomizawa, Kenji; Hanaoka, Yutaka; Toda, Shigeo; Matoba, Shuichiro; Kuroyanagi, Hiroya; Oota, Yasunori

2014-11-01

Anastomotic stricture reportedly often recurs following barium peritonitis, regardless of whether the anastomotic diameter is initially sufficient. However, the causes of repetitive stricture have not been clarified. We report a case that suggests the pathophysiology of recurrent anastomotic strictures following barium peritonitis. The patient was a 39-year-old Japanese man with idiopathic perforation of the descending colon after undergoing an upper gastrointestinal barium contrast study. After emergency peritoneal lavage and diverting colostomy, created using the perforated region, the patient recovered uneventfully and 3 months later, the colostomy was closed and the perforated colon was resected. However, 7 months after colostomy closure, abdominal distention gradually developed, and colonoscopy revealed an anastomotic stricture. The patient was referred to our hospital where he underwent resection of the anastomotic stricture. The surgical specimen exhibited barium granulomas not only in the subserosa of the entire specimen, but also in the submucosa and lamina propria localized in the anastomotic site. These findings suggest that barium was embedded in the submucosa and lamina propria with manipulation of the stapled anastomosis and that the barium trapped in the anastomotic site caused persistent inflammation, resulting in an anastomotic stricture.

Barium enema findings of milk allergy in infants

International Nuclear Information System (INIS)

Kim, Gyoung Ju; Kim, Mi Jeong; Lee, Hee Jung

2006-01-01

We wanted to evaluate the barium enema findings of milk allergy in infants. Retrospective evaluation of the plain abdominal radiography and barium enema findings was performed in fifteen young infants suffering with milk allergy. The presence of gaseous distension, rectal gas, paralytic ileus and mechanical obstruction was evaluated on the plain radiography. The presence of spasm, a transitional zone, a reversed rectosigmoid index and mucosal irregularity was analyzed on the barium enema; the presence of barium retention was also evaluated on 24-hour-delayed plain radiography. Paralytic ileus was the most common finding on the plain radiography (93%). On the barium enema, continuous spasm of the colon, ranging from the rectum to the descending colon, was revealed in ten infants (67%). A transitional zone was observed in one infant and a reversed rectosigmoid index was revealed in four. Mucosal irregularity was observed in two infants. Barium retention was demonstrated in 11 of fifteen cases: throughout the entire colon (n = 3), from the rectum to the descending colon (n = 7), and up to the transverse colon (n = 1). The most common barium enema finding of milk allergy in infants was spasm of the distal colon. The other findings were a transitional zone, a reversed rectosigmoid index, mucosal irregularity and barium retention

INFLUENCE OF BARIUM OXIDE ADDITIONS ON PORTLAND CLINKER

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Anezka Zezulova

2016-12-01

Full Text Available Nowadays, nuclear power plants are widespread around the world and research is of great interest. Together with nuclear research, shielding of different types of radiation is an important current topic of research aiming at their safety. Portland cement has been an elementary building material for centuries. Since barium is very efficient in shielding different types of radiation, it can be assumed that the radiation shielding capability of cement can be improved by incorporation of barium. This work deals with the influence of barium oxide, added in the form of barium carbonate and sulphate, on the formation and properties of Portland clinker. The structure of burnt clinkers and the ratio of clinker phases were studied by polarizing microscopy and by X-ray diffraction. With increasing barium content, the alite-belite ratio decreases and the content of free lime gradually increases. Moreover, sulphates induce the growth of alite crystals. The ability of barium to be a part of the clinker minerals was observed by scanning electron microscopy. Belite and clinker melt contain the highest amount of barium, but aggregates of barium oxide are formed in the clinker melt. Furthermore, the rate of alite crystallization was studied under isothermal conditions.

Observed Barium Emission Rates

Science.gov (United States)

Stenbaek-Nielsen, H. C.; Wescott, E. M.; Hallinan, T. J.

1993-01-01

The barium releases from the CRRES satellite have provided an opportunity for verifying theoretically calculated barium ion and neutral emission rates. Spectra of the five Caribbean releases in the summer of 1991 were taken with a spectrograph on board a U.S. Air Force jet aircraft. Because the line of sight release densities are not known, only relative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other observations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with photometric observations. It has been postulated that charge exchange between neutral barium and oxygen ions represents a significant source for ionization. If so. it should be associated with emissions at 4957.15 A and 5013.00 A, but these emissions were not detected.

Effects of barium concentration on oropharyngeal swallow timing measures.

Science.gov (United States)

Stokely, Shauna L; Molfenter, Sonja M; Steele, Catriona M

2014-02-01

Videofluoroscopy is commonly used for evaluating oropharyngeal swallowing but requires radiopaque contrast (typically barium). Prior studies suggest that some aspects of swallowing, including timing measures of oral and pharyngeal bolus transit, vary depending on barium concentration. The aim of our study was to identify timing differences in healthy swallowing between "thin" (40 % w/v concentration) and "ultrathin" (22 % w/v concentration) barium solutions. Twenty healthy adults (Ten women; mean age = 31 years) each performed a series of three noncued 5-ml swallows each of ultrathin and thin liquid barium solutions in videofluoroscopy. Timing measures were compared between barium concentrations using a mixed-model ANOVA. The measures of interest were stage transition duration, pharyngeal transit time, and duration of upper esophageal sphincter opening. Significant differences were observed in the timing measures of swallowing with respect to barium concentration. In all cases, longer durations were seen with the higher barium concentration. Barium concentration influences timing parameters in healthy swallowing, even between ultrathin and thin concentrations. Clinicians need to understand and control for the impact of different barium stimuli on swallowing physiology.

Atomization mechanisms for barium in furnace atomic absorption spectrometry

International Nuclear Information System (INIS)

Styris, D.L.

1984-01-01

Atomic absorption spectrometry and mass spectrometry are used simultaneously in order to elucidate atomization mechanisms of barium dichloride in pyrolytic graphite, vitreous carbon, and tantalum furnaces. Gas-phase barium dicarbide is observed to appear concurrently with the free barium. Barium oxide and barium dihydroxide precursors appear with the chlorides. Surface reactions involving species that are absorbed on the various furnaces are postulated to explain the appearances of the species that are observed in the gas phase. 49 references, 4 figures, 1 table

Double contrast barium meal and acetylcysteine

International Nuclear Information System (INIS)

Kinnunen, J.; Pietilae, J.; Ahovuo, J.; Mankinen, P.; Tervahartiala, P.

1989-01-01

In a prospective double blind study, acetylcysteine, a local and systemic respiratory tract mucolytic agent, or a placebo, were given to 100 patients prior to a double contrast barium meal to decrease the gastric mucus viscosity and to make the mucus layer thinner, in order to permit barium to outline the furrows surrounding the areae gastricae instead of the overlying thick mucus. However, acetylcysteine failed to improve either visualization of the areae gastricae or the general quality of the double contrast barium meal. (orig.)

Nanoparticles of barium induce apoptosis in human phagocytes.

Science.gov (United States)

Mores, Luana; França, Eduardo Luzia; Silva, Núbia Andrade; Suchara, Eliane Aparecida; Honorio-França, Adenilda Cristina

2015-01-01

Nutrients and immunological factors of breast milk are essential for newborn growth and the development of their immune system, but this secretion can contain organic and inorganic toxins such as barium. Colostrum contamination with barium is an important issue to investigate because this naturally occurring element is also associated with human activity and industrial pollution. The study evaluated the administration of barium nanoparticles to colostrum, assessing the viability and functional activity of colostral mononuclear phagocytes. Colostrum was collected from 24 clinically healthy women (aged 18-35 years). Cell viability, superoxide release, intracellular Ca(2+) release, and phagocyte apoptosis were analyzed in the samples. Treatment with barium lowered mononuclear phagocyte viability, increased superoxide release, and reduced intracellular calcium release. In addition, barium increased cell death by apoptosis. These data suggest that nanoparticles of barium in colostrum are toxic to cells, showing the importance of avoiding exposure to this element.

Barium appendicitis after upper gastrointestinal imaging.

Science.gov (United States)

Novotny, Nathan M; Lillemoe, Keith D; Falimirski, Mark E

2010-02-01

Barium appendicitis (BA) is a rarely seen entity with fewer than 30 reports in the literature. However, it is a known complication of barium imaging. To report a case of BA in a patient whose computed tomography (CT) scan was initially read as foreign body ingestion. An 18-year-old man presented with right lower quadrant pain after upper gastrointestinal imaging 2 weeks prior. A CT scan was obtained of his abdomen and pelvis that revealed a finding that was interpreted as a foreign body at the area of the terminal ileum. A plain X-ray study of the abdomen revealed radiopaque appendicoliths. Pathology confirmed the diagnosis of barium appendicitis. BA is a rare entity and the pathogenesis is unclear. Shorter intervals between barium study and presentation with appendicitis usually correlate with fewer complications. Copyright (c) 2010 Elsevier Inc. All rights reserved.

Cost-effectiveness of barium enemas performed by radiographers

International Nuclear Information System (INIS)

Brown, Lorraine; Desai, Sharad

2002-01-01

AIM: To assess the cost-effectiveness of barium enemas performed by radiographers compared to those performed by consultant radiologists. METHOD: Prospective study of 200 barium enemas carried out by a senior radiographer and a consultant radiologist. The sample was a consecutive sample of adult out-patients over a 3-month period, with no exclusion. The length of time of the enema and the numbers and grades of staff involved in the procedure were recorded. This was translated into staffing costs using the appropriate pay scales. RESULTS: The barium enemas performed by the superintendent radiographer were more cost-effective than those performed by the consultant radiologist (1406 pounds for 100 radiographer-performed barium enemas compared to 1787 pounds for 100 carried out by the consultant radiologist). CONCLUSION: In terms of staffing costs, radiographers performing barium enemas not only liberates radiologist time, it is also a cost-effective method of providing an out-patient barium enema service. Brown, L. and Desai, S. (2002)

Kinematic and spatial distributions of barium stars - are the barium stars and Am stars related?

International Nuclear Information System (INIS)

Hakkila, J.

1989-01-01

The possibility of an evolutionary link between Am stars and barium stars is considered, and an examination of previous data suggests that barium star precursors are main-sequence stars of intermediate mass, are most likely A and/or F dwarfs, and are intermediate-mass binaries with close to intermediate orbital separations. The possible role of mass transfer in the later development of Am systems is explored. Mass transfer and loss from systems with a range of masses and orbital separations may explain such statistical peculiarities of barium stars as the large dispersion in absolute magnitude, the large range of elemental abundances from star to star, and the small number of stars with large peculiar velocities. 93 refs

Aspiration of Barium Contrast

OpenAIRE

Fuentes Santos, Cristina; Steen, Bárbara

2014-01-01

The aspiration of barium contrast is a rare complication that may occur during studies of the digestive tract. Barium is an inert material that can cause anywhere from an asymptomatic mechanical obstruction to serious symptoms of respiratory distress that can result in patient death. We present the case of a 79-year-old male patient in whom we observed the presence of contrast medium residue in the lung parenchyma as an incidental finding during hospitalization. When the patient’s medical fil...

Enterogastroesophageal reflux during barium enema: Report of a case

International Nuclear Information System (INIS)

Shin, Hyoun Ja; Rhee, Hak Song

1972-01-01

Enterogastric reflux during barium enema examination has been ascribed to various causes including incompetence of the ilepcecal valve, shunt, fistula, excessive barium etc. Recently we have encountered a case of complete enterogastroesphageal regurgitation during barium enema examination performed for the reduction of the ileocolic intuosusception in 6 months old baby. The regurgitation occurred only in the first of two barium enema examinations conducted at one month interval for recurring intussusception. The barium-saline solution used in the present study was not more than 350 ml in quantity. No organic or physical causes of such a complete regurgitation could be determined

Laser cooling and trapping of barium

NARCIS (Netherlands)

De, Subhadeep

2008-01-01

Laser cooling and trapping of heavy alkaline-earth element barium have been demonstrated for the first time ever. For any possible cycling transition in barium that could provide strong cooling forces, the excited state has a very large branching probability to metastable states. Additional lasers

Barium determination in gastric contents, blood and urine by inductively coupled plasma mass spectrometry in the case of oral barium chloride poisoning.

Science.gov (United States)

Łukasik-Głębocka, Magdalena; Sommerfeld, Karina; Hanć, Anetta; Grzegorowski, Adam; Barałkiewicz, Danuta; Gaca, Michał; Zielińska-Psuja, Barbara

2014-01-01

A serious case of barium intoxication from suicidal ingestion is reported. Oral barium chloride poisoning with hypokalemia, neuromuscular and cardiac toxicity, treated with intravenous potassium supplementation and hemodialysis, was confirmed by the determination of barium concentrations in gastric contents, blood, serum and urine using the inductively coupled plasma mass spectrometry method. Barium concentrations in the analyzed specimens were 20.45 µg/L in serum, 150 µg/L in blood, 10,500 µg/L in urine and 63,500 µg/L in gastric contents. Results were compared with barium levels obtained from a non-intoxicated person. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Coprecipitation of iron and silver with barium fluoride

International Nuclear Information System (INIS)

Kopilova, N.V.; Khamidov, B.O.; Kashina, Z.A.; Ikrami, D.D.

1986-01-01

Distribution of trace contaminants of iron and silver at coprecipitation of barium fluoride is studied in present work. It is defined that iron almost completely coprecipitated with barium fluoride in wide range of ph 5.5-12. Silver coprecipitated with barium fluoride in ph range 4-7. The value of coprecipitation varies from 94% to 100%.

Barium Sulfate

Science.gov (United States)

... uses a computer to put together x-ray images to create cross-sectional or three dimensional pictures of the inside of the body). Barium sulfate is in a class of medications called radiopaque contrast media. It works by coating the esophagus, stomach, or ...

Synthesis, photoluminescence and magnetic properties of barium vanadate nanoflowers

International Nuclear Information System (INIS)

Xu, Jing; Hu, Chenguo; Xi, Yi; Peng, Chen; Wan, Buyong; He, Xiaoshan

2011-01-01

Graphical abstract: The flower-shaped barium vanadate was obtained for the first time. The photoluminescence and magnetic properties of the barium vanadate nanoflowers were investigated at room temperature. Research highlights: → In the paper, the flower-shaped barium vanadate were obtained for the first time. The CHM method used here is new and simple for preparation of barium vanadate. → The photoluminescence and magnetic properties of the barium vanadate nanoflowers were investigated at room temperature. The strong bluish-green emission was observed. → The ferromagnetic behavior of the barium vanadate nanoflowers was found with saturation magnetization of about 83.50 x 10 -3 emu/g, coercivity of 18.89 Oe and remnant magnetization of 4.63 x 10 -3 emu/g. → The mechanisms of PL and magnetic property of barium vanadate nanoflowers have been discussed. -- Abstract: The flower-shaped barium vanadate has been obtained by the composite hydroxide mediated (CHM) method from V 2 O 5 and BaCl 2 at 200 o C for 13 h. XRD and XPS spectrum of the as-synthesized sample indicate it is hexagonal Ba 3 V 2 O 8 with small amount of Ba 3 VO 4.8 coexistence. Scan electron microscope and transmission electron microscope display that the flower-shaped crystals are composed of nanosheets with thickness of ∼20 nm. The UV-visible spectrum shows that the barium vanadate sample has two optical gaps (3.85 eV and 3.12 eV). Photoluminescence spectrum of the barium vanadate flowers exhibits a visible light emission centered at 492 and 525 nm which might be attributed to VO 4 tetrahedron with T d symmetry in Ba 3 V 2 O 8 . The ferromagnetic behavior of the barium vanadate nanoflowers has been found with saturation magnetization of about 83.50 x 10 -3 emu/g, coercivity of 18.89 Oe and remnant magnetization of 4.63 x 10 -3 emu/g, which is mainly due to the presence of a non-orthovanadate phase with spin S = 1/2.

40 CFR 721.10011 - Barium calcium manganese strontium oxide.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium calcium manganese strontium... Specific Chemical Substances § 721.10011 Barium calcium manganese strontium oxide. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium calcium...

History and challenges of barium titanate: Part I

Directory of Open Access Journals (Sweden)

Vijatović M.M.

2008-01-01

Full Text Available Barium titanate is the first ferroelectric ceramics and a good candidate for a variety of applications due to its excellent dielectric, ferroelectric and piezoelectric properties. Barium titanate is a member of a large family of compounds with the general formula ABO3 called perovskites. Barium titanate can be prepared using different methods. The synthesis method depends on the desired characteristics for the end application. The used method has a significant influence on the structure and properties of barium titanate materials. In this review paper, Part I contains a study of the BaTiO3 structure and frequently used synthesis methods.

Blood pressure changes during barium enema

International Nuclear Information System (INIS)

Roach, S.C.; Martin, O.J.D.; Owen, A.; Martin, D.F.

2001-01-01

AIMS: To document blood pressure changes during barium enema examination and to determine at what point in the examination changes are likely to occur. METHODS AND RESULTS: Blood pressure measurements were taken at seven points during the course of barium enema examination in 107 consecutive patients. We found that patients over the age of 60 years had statistically significant decreases in blood pressure when they were stood up during the course of the examination. Many of these patients were asymptomatic. Patients who had symptoms (15/107, 14%) when standing up had a degree of hypotension. The duration of barium enema examination is longer in those patients who experience symptoms. CONCLUSION: During a barium enema examination hypotension occurs at the point of standing up more frequently in patients over 60 years and in those who suffer symptoms at this time. Patients who fall into one of these groups should be considered at risk of fainting at this point in the examination. A modified technique to avoid standing should be considered in at-risk patients. Roach, S.C. et al. (2001)

Gluten content of barium sulfate suspensions used for barium swallows in patients with celiac disease.

Science.gov (United States)

Chiu, Jennifer G; Shin, Yoona; Patel, Priti N; Mangione, Robert A

2014-01-01

To determine the availability and accuracy of information provided by hospitals, imaging centers, and manufacturers regarding gluten in barium sulfate suspensions. A total of 105 facilities were contacted via telephone to determine the gluten content of the contrast media used in those facilities. Manufacturers were contacted and their Web sites reviewed to determine the gluten content of their barium products. Thirty-nine percent of the hospitals and 52% of the imaging centers were not aware of the gluten content of the contrast media they used. Twenty-nine-and-a-half percent of the respondents provided the correct gluten content. The manufacturers noted that 5 products were tested and confirmed gluten free, 1 product was not tested but described as gluten free, 1 product's gluten content depended upon its flavor, and 1 product was reported to contain gluten. Clinicians caring for patients with celiac disease or patients who choose to restrict their gluten consumption must ensure that the barium sulfate suspension ingested is gluten free. It can be difficult to determine the gluten content of barium sulfate, as a majority of radiology departments and imaging centers did not know whether the product they use is gluten free. Educating staff members and improving product labeling would benefit the quality of care provided to patients with celiac disease.

Barium transport in the hot spot region of fluorescent lamps

International Nuclear Information System (INIS)

Sigeneger, F; Rackow, K; Uhrlandt, D; Ehlbeck, J; Lieder, G

2010-01-01

The transport of barium atoms and ions in the vicinity of the hot spot in fluorescent lamps operating at 25 kHz is investigated by a combined experimental and theoretical approach. By laser-induced fluorescence, the particle densities of barium atoms and ions were measured time-resolved at different distances from the spot centre. In addition, the time-dependent cathode fall voltage was measured using an improved band method. The model combines a kinetic part for the electrons with a fluid part for the barium atoms and ions. Both parts are spatially resolved in spherically symmetric geometry. The space-dependent electron Boltzmann equation yields the electron density and the ionization rate coefficient of barium as functions of the cathode fall voltage. These results are used to solve the time-dependent particle balance equations of barium atoms and ions which include the ionization of barium as gain and loss terms, respectively. Good agreement between the measured and calculated particle densities of barium atoms is obtained. A sensitive dependence of the ionization frequency and of the barium particle densities on the cathode fall voltage was found.

Creating unstable velocity-space distributions with barium injections

International Nuclear Information System (INIS)

Pongratz, M.B.

1983-01-01

Large Debye lengths relative to detector dimensions and the absence of confining walls makes space an attractive laboratory for studying fundamental theories of plasma instabilities. However, natural space plasmas are rarely found displaced from equilibrium enough to permit isolation and diagnosis of the controlling parameters and driving conditions. Furthermore, any plasma or field response to the departure from equilibrium can be masked by noise in the natural system. Active experiments provide a technique for addressing the chicken or egg dilemma. Early thermite barium releases were generally conducted at low altitudes from sounding rockets to trace electric fields passively or to study configuration-space instabilities. One can also study velocity-space instabilities with barium releases. Neutral barium vapor releases wherein a typical speed greatly exceeds the thermal speed can be used to produce barium ion velocity-space distributions that should be subject to a number of microinstabilities. We examine the ion velocity-space distributions resulting from barium injections from orbiting spacecraft and shaped-charges

Evaluation of gastrointestinal tract transit times using barium-impregnated polyethylene spheres and barium sulfate suspension in a domestic pigeon (Columba livia) model.

Science.gov (United States)

Bloch, Rebecca A; Cronin, Kimberly; Hoover, John P; Pechman, Robert D; Payton, Mark E

2010-03-01

Barium impregnated polyethylene spheres (BIPS) are used in small animal medicine as an alternative to barium sulfate for radiographic studies of the gastrointestinal tract. To determine the usefulness of BIPS as an alternative to barium suspension in measuring gastrointestinal (GI) transit time for avian species, ventrodorsal radiographs were used to follow the passage of BIPS and 30% barium sulfate suspension through the GI tracts of domestic pigeons (Columba livia). Gastrointestinal transit times of thirty 1.5-mm BIPS administered in moistened gelatin capsules and 30% barium sulfate suspension gavaged into the crop were compared in 6 pigeons. Although the barium suspension passed out of the GI tract of all pigeons within 24 hours, the 1.5-mm BIPS remained in the ventriculus for 368.0 +/- 176.8 hours and did not clear the GI tract for 424.0 +/- 204.6 hours. Although the times for passage of BIPS and 30% barium sulfate suspension from the crop into the ventriculus were not significantly different (P = .14), the times for passage of BIPS from the ventriculus into the large intestine-cloaca and for clearance from the GI tract of the pigeons were significantly longer (P barium sulfate suspension. From the results of this study, we conclude that BIPS are not useful for radiographically evaluating GI transit times in pigeons and are unlikely to be useful in other avian species that have a muscular ventriculus. BIPS may or may not be useful for evaluating GI transit times in species that lack a muscular ventriculus.

Dynamical symmetry breaking in barium isotopes

International Nuclear Information System (INIS)

Rawat, Bir Singh; Chattopadhyay, P.K.

1997-01-01

The isotopes of Xe with mass numbers 124, 126, 128, 130 and the isotopes of barium with mass numbers 128, 130, 132, 134 were shown to correspond to the O(6) dynamical symmetry of IBM. In the investigation of the dynamical symmetry breaking in this region, the barium isotopes for departures from O(6) symmetry have been studied

Late changes in barium sulfate aspiration: HRCT features

International Nuclear Information System (INIS)

Voloudaki, A.; Ergazakis, N.; Gourtsoyiannis, N.

2003-01-01

Aspiration of barium sulfate occurs accidentally. Lung reaction is usually mild in the early phase due to inert character of the substance and long-term reactions or late toxicities are not expected. Little if any fibrotic response is speculated. We present a case with barium aspiration, studied by high-resolution computed tomography (HRCT) 1 year after the event, as late pulmonary sequelae studied by CT have not been described yet, to the best of our knowledge. The HRCT revealed thickened interlobular septa, subpleural lines, subpleural cysts, and centrilobular micronodules along with barium particles in a subpleural distribution. Those findings indicated that barium is capable of producing mild though silent clinically fibrosis. (orig.)

Barium low concentration determination in solutions using X rays energy spectrometry

International Nuclear Information System (INIS)

Barbosa, Joao Batista Santos; Pereira, Jose dos Santos Jorge

1999-01-01

This work was proposed to establish an analytical methodology for barium determination in samples from the Waste Supervision of CDTN. Barium is the focus here because it has the same chemical behaviour as radium. Therefore, barium can replace it as an inactive tracer in contention matrix studies. The methodology is made up of two phases; physical concentration and barium determination by an Energy Dispersive Spectrometer using an Am 241 photon excitation system. A very good set of results is found when Am 241 is used in fluorescing barium atoms. This fact, in addition to the physical concentration process, allows to detect up 12 ppb of elementary barium. (author)

Electrooptic and piezoelectric measurements in photorefractive barium titanate and strontium barium niobate

International Nuclear Information System (INIS)

Ducharme, S.; Feinberg, J.; Neurgaonkar, R.R.

1987-01-01

The authors measured the low-frequency (''unclamped'') electrooptic and piezoelectric coefficients in undoped BaTiO/sub 3/ and Sr/sub x/Ba/sub 1-x/Nb/sub 2/O/sub 6/ (chi - 0.61) crystals using interferometric techniques. The contribution of the piezoelectric effect to the Pockels measurement is discussed. For an applied ac electric field in the range 0.1-200 V/cm, the electrooptic and piezoelectric effects are linear in the magnitude of of the applied field and independent of its frequency in the range of 10 Hz-100 kHz. The unclamped electrooptic coefficients of poled BaTiO/sub 3/ single crystals are r/sub 13/ = 19.5 +- 1 pm/V and r/sub 33/ = 97 +- 7 pm/V, and for strontium barium niobate are r/sub 13/ = 47 +- 5 pm/V and r/sub 33/ = 235 +- 21 pm/V, all measured at a wavelength of 514.5 nm and at T = 23 0 C. For the barium titanate samples the measured Pockels coefficient r/sub c/ identical to r/sub 33/ - (n/sub 1//n/sub 3/)/sup 3/r/sub 13/ = 79 +- 6 pm/V in good agreement with the value r/sub c/ = 76 +- 7 pm/V computed from the above values of r/sub 13/ and r/sub 33/, where n/sub 1/ and n/sub 3/ are the ordinary and extraordinary indexes of refraction, respectively. The measured piezoelectric coefficient is d/sub 23/ = +28.7 +- 2 pm/V for barium titanate, and is d/sub 23/ = +24.6 +- 2 pm/V for strontium barium niobate. They also measured the photoreflective coupling of two optical beams in the crystals, and they show that the dependence of the coupling strength on beam polarization is in fair agreement with the measured values of the Pockels coefficients

Selenium Sulfide

Science.gov (United States)

Selenium sulfide, an anti-infective agent, relieves itching and flaking of the scalp and removes the dry, ... Selenium sulfide comes in a lotion and is usually applied as a shampoo. As a shampoo, selenium ...

Neutron diffraction investigations of the superionic conductors lithium sulfide and sodium sulfide

International Nuclear Information System (INIS)

Altorfer, F.

1990-03-01

Statics and dynamics of the superionic conductors lithium sulfide and sodium sulfide were investigated using the following experimental methods: elastic scattering on sodium sulfide powder in the temperature range 20 - 1000 C, elastic scattering on a lithium sulfide single crystal in the temperature range 20 - 700 C, inelastic scattering on a 7 Li 2 S single crystal at 10 K. 34 figs., 2 tabs., 10 refs

Gastrointestinal tract wall visualization and distention during abdominal and pelvic multidetector CT with a neutral barium sulphate suspension: comparison with positive barium sulphate suspension and with water.

Science.gov (United States)

Oliva, M R; Erturk, S M; Ichikawa, T; Rocha, T; Ros, P R; Silverman, S G; Mortele, K J

2012-01-01

When examining patients with contrast-enhanced multidetector-row CT, we determined if the stomach and small bowel were visualized and distended better with a neutral barium sulphate suspension than with positive barium sulphate suspension or water. After obtaining approval from our institutional review board, 156 patients (women: 84; mean age: 54 yrs) with no history of gastrointestinal tract disease were randomized prospectively to receive orally either 900 ml of neutral (0.1% w/v) barium sulphate suspension (n = 53), 900 ml of positive (2.1% w/v) barium sulphate suspension (n = 53), or 900 ml of water (n = 50), prior to undergoing contrast-enhanced abdominal and pelvic multidetector-row CT. Two independent radiologists evaluated the stomach, and small bowel, for luminal distension and wall visualization, using a five point scale. Results were compared using Kruskal-Wallis and Mann-Whitney U tests. The walls of the stomach, and small bowel were visualized better in patients who were administered neutral barium sulphate suspension than those who were administered either positive barium sulphate suspension (p barium sulphate suspension, the stomach and small bowel were distended better compared to patients administered water (p barium sulphate suspension (p contrast-enhanced abdominal and pelvic multidetector-row CT, orally administered neutral barium sulphate suspension allows the gastrointestinal tract to be visualized and distended better than either positive barium sulphate suspension, or water.

Barium and radium migration in unconsolidated Canadian geological materials

International Nuclear Information System (INIS)

Gillham, R.W.; Sharma, H.D.; Reddy, M.R.; Cooper, E.L.; Cherry, J.A.

1981-05-01

This report describes the results of laboratory studies on the distribution coefficients of radium and barium in samples of unconsolidated geologic materials. Graphs of Ksub(d) versus solution concentration for the respective elements showed constant Ksub(d) values in the low concentration range suggesting that, at low concentrations, a distribution coefficient is a valid means of representing the geochemical reactions of both barium and radium. The Ksub(d) values for barium range between 60 and 3500 ml/g. The values appear to be influenced by the amount of barium occurring naturally in the soil materials and thus there is little possiblility of using barium as an analog of radium in laboratory experiments. The Ksub(d) values of radium vary from 50 to 1000 ml/g indicating that a wide range of geological materials have a substantial capacity to retard the migration of radium

Time requirement for barium reduction in intussusception

International Nuclear Information System (INIS)

Hwang, Hye Eun; Kim, Seung Ho; Kang, In Young; Park, Byoung Lan; Kim, Byoung Geun

1988-01-01

During the period between January 1985 and December 1987, barium reduction was performed in 146 cases of intussusception who were admitted to Kwangju Christian Hospital. The results were as follows: 1. Success rate to the symptom duration is relatively constant. 2. The success rate in infants with severe dehydration was 50% but it was gradually increased in infants with moderate dehydration and in infants with mild dehydration, 83.3% and 100% respectively. 3. The success rate of 12 cases in severely dehydrated infants with positive dissection sign was 16.7%. 4. The success rate of 15 cases in moderately dehydrated infants with positive dissection sign was 66.7%. 5. The average time requirement for barium reduction was 58.3 minutes. No serious complications were noted during barium reduction, except mild vomiting. 6. With above results, it is desirable that barium reduction should be performed according to the patient's physical status and radiologic findings.

Radiation doses to patients undergoing barium meal and barium enema examinations

International Nuclear Information System (INIS)

Delichas, M. G.; Hatziioannou, K.; Papanastassiou, E.; Albanopoulou, P.; Chatzi, E.; Sioundas, A.; Psarrakos, K.

2004-01-01

The radiation doses received by patients during 41 barium meal (BM) and 42 barium enema (BE) examinations in two Greek hospitals are presented. Radiation dose was measured in terms of the dose area product (DAP). The effective dose and doses to certain organs were estimated using the ODS-60 software. Mean total DAP values were found to be 25 ± 11 Gy cm 2 for BM and 60 ± 35 Gy cm 2 for BE examinations, whereas the estimated mean values of effective dose were 8.6 ± 4.0 and 24 ± 16 mSv respectively. DAP to effective dose conversion coefficients were estimated to be 0.34 mSv per Gy cm 2 for BM and 0.41 mSv per Gy cm 2 for BE. (authors)

Barium peritonitis following upper gastrointestinal series: A case report

Energy Technology Data Exchange (ETDEWEB)

Ko, Su Jin; Hwang, Ji Young; Kim, Yong Jin; Hong, Seong Sook [Soonchunhyang University College of Medicine, Seoul Hospital, Seoul (Korea, Republic of)

2017-06-15

We report a rare case of barium peritonitis following an upper gastrointestinal (GI) series and its imaging findings in a 74-year-old female. Barium peritonitis is a rare but life-threatening complication of GI contrast investigation. Therefore, clinical awareness of barium peritonitis as a complication of GI tract contrast investigation would help to prevent such a complication and manage the patients properly.

Barium peritonitis following upper gastrointestinal series: A case report

International Nuclear Information System (INIS)

Ko, Su Jin; Hwang, Ji Young; Kim, Yong Jin; Hong, Seong Sook

2017-01-01

We report a rare case of barium peritonitis following an upper gastrointestinal (GI) series and its imaging findings in a 74-year-old female. Barium peritonitis is a rare but life-threatening complication of GI contrast investigation. Therefore, clinical awareness of barium peritonitis as a complication of GI tract contrast investigation would help to prevent such a complication and manage the patients properly

Air (CO2) double-contrast barium enteroclysis.

Science.gov (United States)

Maglinte, Dean D T; Kohli, Marc D; Romano, Stefania; Lappas, John C

2009-09-01

In the 1980s and 1990s in North America and Europe, air (CO(2)) double-contrast barium enteroclysis took a back seat to biphasic methylcellulose double-contrast enteroclysis in the investigation of small-bowel diseases. The widespread application of capsule endoscopy in the 21st century has identified a number of limitations of radiologic examinations in the investigation of mucosal diseases of the small intestine. Evidence-based studies comparing barium, computed tomographic (CT), and magnetic resonance (MR) enteroclysis have shown that in spite of improvements in small-bowel examination methods using CT and MR, barium examinations remain superior in the depiction of mucosal abnormalities, particularly the apthoid lesions of early Crohn disease. Barium small-bowel examinations have been recommended in the patient with a negative CT or MR enteroclysis study where the pretest probability of Crohn disease is high. A recent prospective comparison of methylcellulose double-contrast barium enteroclysis to capsule endoscopy with review of the literature has shown that air enteroclysis depicts mucosal details better than does methylcellulose double-contrast enteroclysis because of the "washout" effect of methylcellulose on superficial mucosal features. Recent articles have shown that air enteroclysis compares favorably with wireless capsule endoscopy and double-balloon endoscopy in the diagnosis of mucosal abnormalities of the small bowel. This article describes the authors' technique of performing air double-contrast enteroclysis, its clinical indications, and its pitfalls.

Surface studies of barium and barium oxide on tungsten and its application to understanding the mechanism of operation of an impregnated tungsten cathode

Science.gov (United States)

Forman, R.

1976-01-01

Surface studies have been made of multilayer and monolayer films of barium and barium oxide on a tungsten substrate. The purpose of the investigation was to synthesize the surface conditions that exist on an activated impregnated tungsten cathode and obtain a better understanding of the mechanism of operation of such cathodes. The techniques employed in these measurements were Auger spectroscopy and work-function measurements. The results of this study show that the surface of an impregnated cathode is identical to that observed for a synthesized monolayer or partial monolayer of barium on oxidized tungsten by evaluating Auger spectra and work-function measurements. Data obtained from desorption studies of barium monolayers on a tungsten substrate in conjunction with Auger and work-function results have been interpreted to show that throughout most of its life an impreganated cathode has a partial monolayer, rather than a monolayer, of barium on its surface.

Effects of chemesthetic stimuli mixtures with barium on swallowing apnea duration.

Science.gov (United States)

Todd, J Tee; Butler, Susan G; Plonk, Drew P; Grace-Martin, Karen; Pelletier, Cathy A

2012-10-01

This study tested the hypotheses that swallowing apnea duration (SAD) will increase given barium versus water, chemesthetic stimuli (i.e., water barium, age (older > younger), and genetic taste differences (supertasters > nontasters). Prospective group design. University Medical Center. Eighty healthy women were identified as nontasters and supertasters, equally comprising two age groups: 18 to 35 years and 60+ years. The KayPentax Swallowing Signals Lab was used to acquire SAD via nasal cannula during individually randomized swallows of 5 mL barium, 2.7% w/v citric acid with barium, carbonation with barium, and 50:50 diluted ethanol with barium. Data were analyzed using path analysis, with the mediator of chemesthetic perception, adjusted for repeated measures. Significant main effects of age (P = .012) and chemesthetic stimuli (P = .014) were found, as well as a significant interaction between chemesthetic stimuli and age (P = .028). Older women had a significantly longer SAD than younger women. Post hoc analyses revealed that barium mixed with ethanol elicited a significantly longer SAD than other bolus conditions, regardless of age group. There were no significant differences in SAD between barium and water conditions, and no significant effect of chemesthetic perception (P > .05). Ethanol added to barium elicited longer SAD compared to plain barium, but not the other chemesthetic conditions. Older women had a longer SAD than younger women in all conditions. These findings may influence design of future studies examining effects of various stimuli on SAD. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Effectiveness of therapeutic barium enema for diverticular hemorrhage.

Science.gov (United States)

Matsuura, Mizue; Inamori, Masahiko; Nakajima, Atsushi; Komiya, Yasuhiko; Inoh, Yumi; Kawasima, Keigo; Naitoh, Mai; Fujita, Yuji; Eduka, Akiko; Kanazawa, Noriyoshi; Uchiyama, Shiori; Tani, Rie; Kawana, Kennichi; Ohtani, Setsuya; Nagase, Hajime

2015-05-14

To evaluate the effectiveness of barium impaction therapy for patients with colonic diverticular bleeding. We reviewed the clinical charts of patients in whom therapeutic barium enema was performed for the control of diverticular bleeding between August 2010 and March 2012 at Yokohama Rosai Hospital. Twenty patients were included in the review, consisting of 14 men and 6 women. The median age of the patients was 73.5 years. The duration of the follow-up period ranged from 1 to 19 mo (median: 9.8 mo). Among the 20 patients were 11 patients who required the procedure for re-bleeding during hospitalization, 6 patients who required it for re-bleeding that developed after the patient left the hospital, and 3 patients who required the procedure for the prevention of re-bleeding. Barium (concentration: 150 w%/v%) was administered per the rectum, and the leading edge of the contrast medium was followed up to the cecum by fluoroscopy. After confirmation that the ascending colon and cecum were filled with barium, the enema tube was withdrawn, and the patient's position was changed every 20 min for 3 h. Twelve patients remained free of re-bleeding during the follow-up period (range: 1-19 mo) after the therapeutic barium enema, including 9 men and 3 women with a median age of 72.0 years. Re-bleeding occurred in 8 patients including 5 men and 3 women with a median age of 68.5 years: 4 developed early re-bleeding, defined as re-bleeding that occurs within one week after the procedure, and the remaining 4 developed late re-bleeding. The DFI (disease-free interval) decreased 0.4 for 12 mo. Only one patient developed a complication from therapeutic barium enema (colonic perforation). Therapeutic barium enema is effective for the control of diverticular hemorrhage in cases where the active bleeding site cannot be identified by colonoscopy.

Transient Kinetic Analysis of Hydrogen Sulfide Oxidation Catalyzed by Human Sulfide Quinone Oxidoreductase*

Science.gov (United States)

Mishanina, Tatiana V.; Yadav, Pramod K.; Ballou, David P.; Banerjee, Ruma

2015-01-01

The first step in the mitochondrial sulfide oxidation pathway is catalyzed by sulfide quinone oxidoreductase (SQR), which belongs to the family of flavoprotein disulfide oxidoreductases. During the catalytic cycle, the flavin cofactor is intermittently reduced by sulfide and oxidized by ubiquinone, linking H2S oxidation to the electron transfer chain and to energy metabolism. Human SQR can use multiple thiophilic acceptors, including sulfide, sulfite, and glutathione, to form as products, hydrodisulfide, thiosulfate, and glutathione persulfide, respectively. In this study, we have used transient kinetics to examine the mechanism of the flavin reductive half-reaction and have determined the redox potential of the bound flavin to be −123 ± 7 mV. We observe formation of an unusually intense charge-transfer (CT) complex when the enzyme is exposed to sulfide and unexpectedly, when it is exposed to sulfite. In the canonical reaction, sulfide serves as the sulfur donor and sulfite serves as the acceptor, forming thiosulfate. We show that thiosulfate is also formed when sulfide is added to the sulfite-induced CT intermediate, representing a new mechanism for thiosulfate formation. The CT complex is formed at a kinetically competent rate by reaction with sulfide but not with sulfite. Our study indicates that sulfide addition to the active site disulfide is preferred under normal turnover conditions. However, under pathological conditions when sulfite concentrations are high, sulfite could compete with sulfide for addition to the active site disulfide, leading to attenuation of SQR activity and to an alternate route for thiosulfate formation. PMID:26318450

Transient Kinetic Analysis of Hydrogen Sulfide Oxidation Catalyzed by Human Sulfide Quinone Oxidoreductase.

Science.gov (United States)

Mishanina, Tatiana V; Yadav, Pramod K; Ballou, David P; Banerjee, Ruma

2015-10-09

The first step in the mitochondrial sulfide oxidation pathway is catalyzed by sulfide quinone oxidoreductase (SQR), which belongs to the family of flavoprotein disulfide oxidoreductases. During the catalytic cycle, the flavin cofactor is intermittently reduced by sulfide and oxidized by ubiquinone, linking H2S oxidation to the electron transfer chain and to energy metabolism. Human SQR can use multiple thiophilic acceptors, including sulfide, sulfite, and glutathione, to form as products, hydrodisulfide, thiosulfate, and glutathione persulfide, respectively. In this study, we have used transient kinetics to examine the mechanism of the flavin reductive half-reaction and have determined the redox potential of the bound flavin to be -123 ± 7 mV. We observe formation of an unusually intense charge-transfer (CT) complex when the enzyme is exposed to sulfide and unexpectedly, when it is exposed to sulfite. In the canonical reaction, sulfide serves as the sulfur donor and sulfite serves as the acceptor, forming thiosulfate. We show that thiosulfate is also formed when sulfide is added to the sulfite-induced CT intermediate, representing a new mechanism for thiosulfate formation. The CT complex is formed at a kinetically competent rate by reaction with sulfide but not with sulfite. Our study indicates that sulfide addition to the active site disulfide is preferred under normal turnover conditions. However, under pathological conditions when sulfite concentrations are high, sulfite could compete with sulfide for addition to the active site disulfide, leading to attenuation of SQR activity and to an alternate route for thiosulfate formation. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage

CSIR Research Space (South Africa)

Mulopo, J

2012-01-01

Full Text Available Batch regeneration of barium carbonate (BaCO3) from barium sulphide (BaS) slurries by passing CO2 gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO3 recovery in the Alkali...

21 CFR 201.304 - Tannic acid and barium enema preparations.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Tannic acid and barium enema preparations. 201.304... Tannic acid and barium enema preparations. (a) It has become a widespread practice for tannic acid to be added to barium enemas to improve X-ray pictures. Tannic acid is capable of causing diminished liver...

Effects of Barium Concentration on Oropharyngeal Swallow Timing Measures

OpenAIRE

Stokely, Shauna L.; Molfenter, Sonja M.; Steele, Catriona M.

2013-01-01

Videofluoroscopy is commonly used for evaluating oropharyngeal swallowing but requires radiopaque contrast (typically barium). Prior studies suggest that some aspects of swallowing, including timing measures of oral and pharyngeal bolus transit, vary depending on barium concentration. The aim of our study was to identify timing differences in healthy swallowing between “thin” (40 % w/v concentration) and “ultrathin” (22 % w/v concentration) barium solutions. Twenty healthy adults (Ten women; ...

Barium Depletion in the NSTAR Discharge Cathode After 30,000 Hours of Operation

Science.gov (United States)

Polk, James E.; Capece, Angela M.; Mikellides, Ioannis G.; Katz, Ira

2010-01-01

Dispenser hollow cathodes rely on a consumable supply of barium released by impregnant materials in the pores of a tungsten matrix to maintain a low work function surface. Examinations of cathode inserts from long duration ion engine tests show deposits of tungsten at the downstream end that appear to block the flow of barium from the interior. In addition, a numerical model of barium transport in the insert plasma indicates that the barium partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant barium-producing reaction, and it was postulated previously that this would suppress barium loss in the upstream part of the insert. New measurements of the depth of barium depletion from a cathode insert operated for 30,352 hours reveal that barium loss is confined to a narrow region near the downstream end, confirming this hypothesis.

SULFIDE MINERALS IN SEDIMENTS

Science.gov (United States)

The formation processes of metal sulfides in sediments, especially iron sulfides, have been the subjects of intense scientific research because of linkages to the global biogeochemical cycles of iron, sulfur, carbon, and oxygen. Transition metal sulfides (e.g., NiS, CuS, ZnS, Cd...

Evaluation of barium hydroxide treatment efficacy on a dolomitic marble.

Science.gov (United States)

Toniolo, L; Colombo, C; Realini, M; Peraio, A; Positano, M

2001-01-01

The Arch of Peace, by Luigi Cagnola, is one of the most famous neoclassical monuments in Milan. It has been subjected to conservative intervention in 1998. In the present paper the efficacy of the consolidation by means of barium hydroxide has been evaluated. The stone material showed severe degradation phenomena as: erosion, pulverisation, exfoliation. The analytical data acquired through X-ray diffraction (XRD), infrared spectrophotometry (FTIR) and scanning electron microscopy (SEM-EDX), allowed to compare the conditions of stone before and after the treatment with barium hydroxide. The presence of barium has been put in evidence mainly on the surface as barium sulphate, whereas barium is only sporadically present within the thickness of the decayed material. The treatment was judged not satisfying and its inefficacy is, most probably, due to a not suitable cleaning procedure carried out before the consolidation.

SEPARATION OF BARIUM VALUES FROM URANYL NITRATE SOLUTIONS

Science.gov (United States)

Tompkins, E.R.

1959-02-24

The separation of radioactive barium values from a uranyl nitrate solution of neutron-irradiated uranium is described. The 10 to 20% uranyl nitrate solution is passed through a flrst column of a cation exchange resin under conditions favoring the adsorption of barium and certain other cations. The loaded resin is first washed with dilute sulfuric acid to remove a portion of the other cations, and then wash with a citric acid solution at pH of 5 to 7 to recover the barium along with a lesser amount of the other cations. The PH of the resulting eluate is adjusted to about 2.3 to 3.5 and diluted prior to passing through a smaller second column of exchange resin. The loaded resin is first washed with a citric acid solution at a pH of 3 to elute undesired cations and then with citric acid solution at a pH of 6 to eluts the barium, which is substantially free of undesired cations.

The diagnostic value of barium enema in acute appendicitis

International Nuclear Information System (INIS)

Kim, Yong Ga; Chung, Duck Soo; Kim, Ok Dong

1986-01-01

Acute appendicitis is the most common acute surgical condition of the abdomen. When the clinical presentation is atypical, barium enema has proven to be safe and useful in confirming the diagnosis and reducing the negative surgical exploration. However, the performance of barium enema in acute appendicitis has known contraindication primarily because of fear of leakage by perforation of the inflamed appendix. This study using barium enema as a diagnostic aid in acute appendicitis with atypical clinical presentation was performed to further support the previously noted efficacy and safety of this procedure. The results were as followings: 1. In case of acute appendicitis with atypical clinical presentation, the use of barium enema as a diagnostic aid increased the accuracy of diagnosis and decreased the negative surgical exploration. In women between 11 to 50 years old age, especially, it played important role differentiating appendicitis from nonsurgical acute abdomen. 2. The results of the study were 92.31% in sensitivity, 7.69% in false positive, 6.9% in false negative, and 10.26% in negative appendectomy. 3. None of case of leakage of barium by perforation of the inflamed appendix was noted, therefore, barium enema was thought to be safe as a diagnostic aid in acute appendicitis. 4. A simple partial or non filling of appendix without other associated positive finding could not exclude appendicitis, therefore, close clinical observation was necessary. 5. The positive findings of barium enema and their sensitivity were as followings: 1. Non filling of appendix: 90% 2. Partial filling of appendix: 91.7% 3. Displacement or a local impression on terminal ileum: 100%

Prompt striations observed in a barium thermite release at 335 km

International Nuclear Information System (INIS)

Simons, D.J.; Pongratz, M.B.; Smith, G.M.; Barasch, G.E.; Fitzgerald, T.J.

1981-01-01

Three barium clouds have been released from a single rocket at altitudes of 335, 443, and 535 km. The releases were by means of barium thermite injection. Adding the different cross-field velocity components of the rocket at each of the releases resulted in barium clouds with different kinetic velocity distributions. The barium cloud with the most peaked velocity distribution striated promptly, in good agreement with theoretical predictions based on a kinetic plasma instability. Details of the data analysis and experiment are discussed

Effectiveness of therapeutic barium enema for diverticular hemorrhage

Science.gov (United States)

Matsuura, Mizue; Inamori, Masahiko; Nakajima, Atsushi; Komiya, Yasuhiko; Inoh, Yumi; Kawasima, Keigo; Naitoh, Mai; Fujita, Yuji; Eduka, Akiko; Kanazawa, Noriyoshi; Uchiyama, Shiori; Tani, Rie; Kawana, Kennichi; Ohtani, Setsuya; Nagase, Hajime

2015-01-01

AIM: To evaluate the effectiveness of barium impaction therapy for patients with colonic diverticular bleeding. METHODS: We reviewed the clinical charts of patients in whom therapeutic barium enema was performed for the control of diverticular bleeding between August 2010 and March 2012 at Yokohama Rosai Hospital. Twenty patients were included in the review, consisting of 14 men and 6 women. The median age of the patients was 73.5 years. The duration of the follow-up period ranged from 1 to 19 mo (median: 9.8 mo). Among the 20 patients were 11 patients who required the procedure for re-bleeding during hospitalization, 6 patients who required it for re-bleeding that developed after the patient left the hospital, and 3 patients who required the procedure for the prevention of re-bleeding. Barium (concentration: 150 w%/v%) was administered per the rectum, and the leading edge of the contrast medium was followed up to the cecum by fluoroscopy. After confirmation that the ascending colon and cecum were filled with barium, the enema tube was withdrawn, and the patient’s position was changed every 20 min for 3 h. RESULTS: Twelve patients remained free of re-bleeding during the follow-up period (range: 1-19 mo) after the therapeutic barium enema, including 9 men and 3 women with a median age of 72.0 years. Re-bleeding occurred in 8 patients including 5 men and 3 women with a median age of 68.5 years: 4 developed early re-bleeding, defined as re-bleeding that occurs within one week after the procedure, and the remaining 4 developed late re-bleeding. The DFI (disease-free interval) decreased 0.4 for 12 mo. Only one patient developed a complication from therapeutic barium enema (colonic perforation). CONCLUSION: Therapeutic barium enema is effective for the control of diverticular hemorrhage in cases where the active bleeding site cannot be identified by colonoscopy. PMID:25987779

The impact of digital imaging on patient doses during barium studies

International Nuclear Information System (INIS)

Broadhead, D.A.; Chapple, C.-L.; Faulkner, K.

1995-01-01

Barium studies performed on 10 digital and four non-digital fluoroscopic systems were monitored with dose-area product meters as part of a Regional Patient Dosimetry Audit programme. The data have been collected using a computer to read and reset the dose-area product meter and also to collect patient and examination details. A comparison of dose-area product measurements from digital and non-digital fluoroscopy units on over 10 000 barium studies is presented. The data have been corrected according to patient size. The mean size corrected dose-area product for a barium meal examination was found to be 7.62 Gy cm -2 for a digital set compared with 15.45 Gy cm -2 for a non-digital set with 2462 and 1308 patients included in each measurement series, respectively. Dose-area products were also a factor of approximately two lower for barium enema, barium swallow and barium follow-through examinations performed on digital systems. (author)

Exposure to low-dose barium by drinking water causes hearing loss in mice.

Science.gov (United States)

Ohgami, Nobutaka; Hori, Sohjiro; Ohgami, Kyoko; Tamura, Haruka; Tsuzuki, Toyonori; Ohnuma, Shoko; Kato, Masashi

2012-10-01

We continuously ingest barium as a general element by drinking water and foods in our daily life. Exposure to high-dose barium (>100mg/kg/day) has been shown to cause physiological impairments. Direct administration of barium to inner ears by vascular perfusion has been shown to cause physiological impairments in inner ears. However, the toxic influence of oral exposure to low-dose barium on hearing levels has not been clarified in vivo. We analyzed the toxic influence of oral exposure to low-dose barium on hearing levels and inner ears in mice. We orally administered barium at low doses of 0.14 and 1.4 mg/kg/day to wild-type ICR mice by drinking water. The doses are equivalent to and 10-fold higher than the limit level (0.7 mg/l) of WHO health-based guidelines for drinking water, respectively. After 2-week exposure, hearing levels were measured by auditory brain stem responses and inner ears were morphologically analyzed. After 2-month exposure, tissue distribution of barium was measured by inductively coupled plasma mass spectrometry. Low-dose barium in drinking water caused severe hearing loss in mice. Inner ears including inner and outer hair cells, stria vascularis and spiral ganglion neurons showed severe degeneration. The Barium-administered group showed significantly higher levels of barium in inner ears than those in the control group, while barium levels in bone did not show a significant difference between the two groups. Barium levels in other tissues including the cerebrum, cerebellum, heart, liver and kidney were undetectably low in both groups. Our results demonstrate for the first time that low-dose barium administered by drinking water specifically distributes to inner ears resulting in severe ototoxicity with degeneration of inner ears in mice. Copyright © 2012 Elsevier Inc. All rights reserved.

Barium Titanate Nanoparticles for Biomarker Applications

International Nuclear Information System (INIS)

Matar, O; Hondow, N S; Brydson, R M D; Milne, S J; Brown, A P; Posada, O M; Wälti, C; Saunders, M; Murray, C A

2015-01-01

A tetragonal crystal structure is required for barium titanate nanoparticles to exhibit the nonlinear optical effect of second harmonic light generation (SHG) for use as a biomarker when illuminated by a near-infrared source. Here we use synchrotron XRD to elucidate the tetragonal phase of commercially purchased tetragonal, cubic and hydrothermally prepared barium titanate (BaTiO 3 ) nanoparticles by peak fitting with reference patterns. The local phase of individual nanoparticles is determined by STEM electron energy loss spectroscopy (EELS), measuring the core-loss O K-edge and the Ti L 3 -edge energy separation of the t 2g , e g peaks. The results show a change in energy separation between the t 2g and e g peak from the surface and core of the particles, suggesting an intraparticle phase mixture of the barium titanate nanoparticles. HAADF-STEM and bright field TEM-EDX show cellular uptake of the hydrothermally prepared BaTiO 3 nanoparticles, highlighting the potential for application as biomarkers. (paper)

Neutral barium cloud evolution at different altitudes

International Nuclear Information System (INIS)

Li Lei; Xu Ronglan

2002-01-01

Considering the joint effects of diffusion, collision, oxidation and photoionization, the authors study the evolution of the barium cloud at different altitudes in the space plasma active experiment. The results present the variation of the loss rate, number density distribution and brightness of the barium cloud over the range from 120 to 260 km. This can be divided into oxidation, oxidation plus photoionization and photoionization regions

Fabrication and properties of yttrium doped barium titanate film by RF sputtering

International Nuclear Information System (INIS)

Igarashi, H.; Yuasa, M.; Okazaki, K.

1985-01-01

Semiconductive barium titanate films were fabricated by RF sputtering on fused quartz, alumina and barium titanate ceramic substrates using barium titanate ceramic with a small amount of yttria as a target. The films on the barium titanate substrates turned blue color and showed a small PTC effect by heat-treating at 1000 0 C in the air after deposition at the substrate temperature of 600 0 C

Barium and Tc-poor S stars: Binary masqueraders among carbon stars

OpenAIRE

Jorissen, A.; Van Eck, S.

1997-01-01

The current understanding of the origin of barium and S stars is reviewed, based on new orbital elements and binary frequencies. The following questions are addressed: (i) Is binarity a necessary condition to produce a barium star? (ii) What is the mass transfer mode (wind accretion or RLOF?) responsible for their formation? (iii) Do barium stars form as dwarfs or as giants? (iv) Do barium stars evolve into Tc-poor S stars? (v) What is the relative frequency of Tc-rich and Tc-poor S stars?

Freeze cast porous barium titanate for enhanced piezoelectric energy harvesting

Science.gov (United States)

Roscow, J. I.; Zhang, Y.; Kraśny, M. J.; Lewis, R. W. C.; Taylor, J.; Bowen, C. R.

2018-06-01

Energy harvesting is an important developing technology for a new generation of self-powered sensor networks. This paper demonstrates the significant improvement in the piezoelectric energy harvesting performance of barium titanate by forming highly aligned porosity using freeze casting. Firstly, a finite element model demonstrating the effect of pore morphology and angle with respect to poling field on the poling behaviour of porous ferroelectrics was developed. A second model was then developed to understand the influence of microstructure-property relationships on the poling behaviour of porous freeze cast ferroelectric materials and their resultant piezoelectric and energy harvesting properties. To compare with model predictions, porous barium titanate was fabricated using freeze casting to form highly aligned microstructures with excellent longitudinal piezoelectric strain coefficients, d 33. The freeze cast barium titanate with 45 vol.% porosity had a d 33  =  134.5 pC N‑1 compared to d 33  =  144.5 pC N‑1 for dense barium titanate. The d 33 coefficients of the freeze cast materials were also higher than materials with uniformly distributed spherical porosity due to improved poling of the aligned microstructures, as predicted by the models. Both model and experimental data indicated that introducing porosity provides a large reduction in the permittivity () of barium titanate, which leads to a substantial increase in energy harvesting figure of merit, , with a maximum of 3.79 pm2 N‑1 for barium titanate with 45 vol.% porosity, compared to only 1.40 pm2 N‑1 for dense barium titanate. Dense and porous barium titanate materials were then used to harvest energy from a mechanical excitation by rectification and storage of the piezoelectric charge on a capacitor. The porous barium titanate charged the capacitor to a voltage of 234 mV compared to 96 mV for the dense material, indicating a 2.4-fold increase that was similar to that

Radiation losses in microwave K_u region by conducting pyrrole/barium titanate and barium hexaferrite based nanocomposites

International Nuclear Information System (INIS)

Kaur, Talwinder; Kumar, Sachin; Narang, S.B.; Srivastava, A.K.

2016-01-01

Nanocomposites of substituted barium hexaferrite and barium titanate embedded in a polymer were synthesized via emulsion polymerization. The study was performed by using X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, electron spin resonance spectroscopy, a vibrating sample magnetometer and a vector network analyzer. It is found that maximum radiation loss occur at 16.09 GHz (−14.23 dB) frequency owing to the combined effect of conducting polymer, suitable dielectric and magnetic material. This suggests that prepared material is suitable for radiation losses. Micro structural study reveals the presence of all the phases of the compounds comprises composite. Benzene ring absorption band (at 1183 cm"−"1) in FT-IR spectra illustrates the presence of polymer. Surface morphology reveals the presence of array of particles encapsulated by the polymer. - Highlights: • Composites having polymer, barium titanate and hexaferrite have been successfully prepared. • Effective radiation absorption and losses have been achieved. • Magnetic properties have made an impact on shielding effectiveness.

Barium uranyl diphosphonates

Energy Technology Data Exchange (ETDEWEB)

Nelson, Anna-Gay D., E-mail: nelsoa@umich.edu [Department of Civil Engineering and Geological Sciences and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States); Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109-1005 (United States); Alekseev, Evgeny V. [Institute of Energy and Climate Research (IEK-6), Forschungszentrum Juelich Wilhelm-Johnen-Strasse, Juelich 52428 (Germany); Ewing, Rodney C. [Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, MI 48109-1005 (United States); Albrecht-Schmitt, Thomas E. [Department of Civil Engineering and Geological Sciences and Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, IN 46556 (United States)

2012-08-15

Three Ba{sup 2+}/UO{sub 2}{sup 2+} methylenediphosphonates have been prepared from mild hydrothermal treatment of uranium trioxide, methylendiphosphonic acid (C1P2) with barium hydroxide octahydrate, barium iodate monohydrate, and small aliquots of HF at 200 Degree-Sign C. These compounds, Ba[UO{sub 2}[CH{sub 2}(PO{sub 3}){sub 2}]{center_dot}1.4H{sub 2}O (Ba-1), Ba{sub 3}[(UO{sub 2}){sub 4}(CH{sub 2}(PO{sub 3}){sub 2}){sub 2}F{sub 6}]{center_dot}6H{sub 2}O (Ba-2), and Ba{sub 2}[(UO{sub 2}){sub 2}(CH{sub 2}(PO{sub 3}){sub 2})F{sub 4}]{center_dot}5.75H{sub 2}O (Ba-3) all adopt layered structures based upon linear uranyl groups and disphosphonate molecules. Ba-2 and Ba-3 are similar in that they both have UO{sub 5}F{sub 2} pentagonal bipyramids that are bridged and chelated by the diphosphonate moiety into a two-dimensional zigzag anionic sheet (Ba-2) and a one-dimensional ribbon anionic chain (Ba-3). Ba-1, has a single crystallographically unique uranium metal center where the C1P2 ligand solely bridges to form [UO{sub 2}[CH{sub 2}(PO{sub 3}){sub 2}]{sup 2-} sheets. The interlayer space of the structures is occupied by Ba{sup 2+}, which, along with the fluoride ion, mediates the structure formed and maintains overall charge balance. - Graphical abstract: Illustration of the stacking of the layers in Ba{sub 3}[(UO{sub 2}){sub 4}(CH{sub 2}(PO{sub 3}){sub 2}){sub 2})F{sub 6}]{center_dot}6H{sub 2}O viewed along the c-axis. The structure is constructed from UO{sub 7} pentagonal bipyramidal units, U(1)O{sub 7}=gray, U(2)O{sub 7}=yellow, barium=blue, phosphorus=magenta, fluorine=green, oxygen=red, carbon=black, and hydrogen=light peach. Highlights: Black-Right-Pointing-Pointer The polymerization of the UO{sub 2}{sup 2+} sites to form uranyl dimers leads to structural variations in compounds. Black-Right-Pointing-Pointer Barium cations stitch uranyl diphosphonate anionic layers together, and help mediate structure formation. Black-Right-Pointing-Pointer HF acts as both a

Fabry-Perot measurements of barium temperature in fluorescent lamps

International Nuclear Information System (INIS)

Hadrath, S; Garner, R

2010-01-01

A scanning Fabry-Perot interferometer (FPI) is used to determine the temperature of barium atoms that are liberated from the electrodes of fluorescent lamps during their steady-state operation. Barium, a constituent of the work function lowering emitter material that is placed on the tungsten coil that forms the electrode, is liberated primarily by evaporation from the hot (∼1300 K) thermionic electrode. However, there may be situations or modes of operation in which barium is, in addition, sputtered, a condition which may lead to increased end-darkening, shortened life and increased mercury consumption in the lamp. Using the FPI diagnostic, the occurrence of sputtering is inferred when barium temperatures are much greater than the electrode temperature. The FPI diagnostic senses resonance radiation (λ = 553 nm) emitted by barium atoms excited in the low pressure discharge environment, and infers temperature from the Doppler broadened linewidth. The diagnostic has proven to be successful in a number of situations. Measurements have been made on rare gas discharges and on Hg-argon discharges for different discharge currents, gas pressures and auxiliary coil currents. Measurements are phase resolved for ac-driven discharges.

Barium sulfate suspension as a negative oral contrast agent for MR imaging

International Nuclear Information System (INIS)

Li, K.C.P.; Tart, R.P.; Fitzsimmons, J.R.; Storm, B.; Mao, J.

1989-01-01

Proton spectroscopy with linewidth measurements and MR imaging were performed on various commercially available barium sulfate suspensions as well as inorganic sulfates and barium salts. Approximately 500 mL of 20%, 40%, 60%, and 70% wt/wt single-contrast oral barium sulfate suspensions were administered to four normal volunteers, and MR imaging was performed with both a 1.5-T and a 0.15-T MR imager. As much as 80% of the small bowel and the entire colon were well visualized with the 60% or 70% wt/wt single-contrast barium sulfate suspensions. The authors conclude that barium sulfate suspensions are useful as oral MR contrast agents

Simplified assessment of segmental gastrointestinal transit time with orally small amount of barium

Energy Technology Data Exchange (ETDEWEB)

Yuan, Weitang; Zhang, Zhiyong; Liu, Jinbo; Li, Zhen; Song, Junmin; Wu, Changcai [Department of Colorectal Surgery, The First Affiliated Hospital and Institute of Clinical Medicine, Zhengzhou University, 450052 Zhengzhou (China); Wang, Guixian, E-mail: guixianwang@hotmail.com [Department of Colorectal Surgery, The First Affiliated Hospital and Institute of Clinical Medicine, Zhengzhou University, 450052 Zhengzhou (China)

2012-09-15

Objective: To determine the effectiveness and advantage of small amount of barium in the measurement of gastrointestinal transmission function in comparison with radio-opaque pallets. Methods: Protocal 1: 8 healthy volunteers (male 6, female 2) with average age 40 ± 6.1 were subjected to the examination of radio-opaque pellets and small amount of barium with the interval of 1 week. Protocol 2: 30 healthy volunteers in group 1 (male 8, female 22) with average age 42.5 ± 8.1 and 50 patients with chronic functional constipation in group 2 (male 11, female 39) with average age 45.7 ± 7.8 were subjected to the small amount of barium examination. The small amount of barium was made by 30 g barium dissolved in 200 ml breakfast. After taking breakfast which contains barium, objectives were followed with abdominal X-ray at 4, 8, 12, 24, 48, 72, 96 h until the barium was evacuated totally. Results: Small amount of barium presented actual chyme or stool transit. The transit time of radio-opaque pallets through the whole gastrointestinal tract was significantly shorter than that of barium (37 ± 8 h vs. 47 ± 10 h, P < 0.05) in healthy people. The transit times of barium in constipation patients were markedly prolonged in colon (61.1 ± 22 vs. 37.3 ± 11, P < 0.01) and rectum (10.8 ± 3.7 vs. 2.3 ± 0.8 h, P < 0.01) compared with unconstipated volunteers. Transit times in individual gastrointestinal segments were also recorded by using small amount of barium, which allowed identifying the subtypes of constipation. Conclusion: The small amount barium examination is a convenient and low cost method to provide the most useful and reliable information on the transmission function of different gastrointestinal segments and able to classify the subtypes of slow transit constipation.

Simplified assessment of segmental gastrointestinal transit time with orally small amount of barium

International Nuclear Information System (INIS)

Yuan, Weitang; Zhang, Zhiyong; Liu, Jinbo; Li, Zhen; Song, Junmin; Wu, Changcai; Wang, Guixian

2012-01-01

Objective: To determine the effectiveness and advantage of small amount of barium in the measurement of gastrointestinal transmission function in comparison with radio-opaque pallets. Methods: Protocal 1: 8 healthy volunteers (male 6, female 2) with average age 40 ± 6.1 were subjected to the examination of radio-opaque pellets and small amount of barium with the interval of 1 week. Protocol 2: 30 healthy volunteers in group 1 (male 8, female 22) with average age 42.5 ± 8.1 and 50 patients with chronic functional constipation in group 2 (male 11, female 39) with average age 45.7 ± 7.8 were subjected to the small amount of barium examination. The small amount of barium was made by 30 g barium dissolved in 200 ml breakfast. After taking breakfast which contains barium, objectives were followed with abdominal X-ray at 4, 8, 12, 24, 48, 72, 96 h until the barium was evacuated totally. Results: Small amount of barium presented actual chyme or stool transit. The transit time of radio-opaque pallets through the whole gastrointestinal tract was significantly shorter than that of barium (37 ± 8 h vs. 47 ± 10 h, P < 0.05) in healthy people. The transit times of barium in constipation patients were markedly prolonged in colon (61.1 ± 22 vs. 37.3 ± 11, P < 0.01) and rectum (10.8 ± 3.7 vs. 2.3 ± 0.8 h, P < 0.01) compared with unconstipated volunteers. Transit times in individual gastrointestinal segments were also recorded by using small amount of barium, which allowed identifying the subtypes of constipation. Conclusion: The small amount barium examination is a convenient and low cost method to provide the most useful and reliable information on the transmission function of different gastrointestinal segments and able to classify the subtypes of slow transit constipation

Comparison of pressure between barium reduction and air reduction of the intussusception in children

Energy Technology Data Exchange (ETDEWEB)

Lee, Kyung Hwan; Park, Sang Gyu; Park, Choong Ki; Yoon, Jong Sup [Hallym University College of Medicine, Seoul (Korea, Republic of)

1989-08-15

There are many method of treatment of the intussusception in children, including surgery, barium reduction, air reduction, and saline enema under ultrasonographic monitoring. Among them, barium reduction and air reduction have been used widely as nonsurgical method of treatment in radiologic department. During barium reduction, the bottle filled with barium solution must not be elevated over a 3 feet from the operating table. In air reduction, diagnostic pressure is about 60 mmHg and pressure during reduction usually is maintained between 90 mmHg and 130 mmHg. The authors have studied about pressure difference of barium solution by changing height of the bottle filled with barium solution, and have compared with pressure in air reduction. The results are as follows; 1. Pressure of 20 w/v % barium solution at the 60 cm height is 44.4 mmHg, and 69.6 mmHg at the 90 cm height. 2. Pressure of 40 w/v % barium solution at the 60 cm height is 51.4 mmHg, and 80.1 mmHg at the 90 cm height. 3. Pressure of 40 w/v % barium solution at the 90cm height is much lower than the pressure maintained during air reduction, and this difference in pressure may be one of the causes of low reduction rate in barium reduction then air reduction. 4. The pressure gradient per 10 cm height is about 8.45 mmHg in 20 w/v % barium solution, about 9.21 mmHg in 30 w/v % barium solution, and about 9.72 mmHg 40 w/v % barium solution. 5. Intraluminal pressure difference between the barium reduction and the air reduction is probably of the major causes of rapid diagnosis and high reduction rate in the air reduction.

Comparison of pressure between barium reduction and air reduction of the intussusception in children

International Nuclear Information System (INIS)

Lee, Kyung Hwan; Park, Sang Gyu; Park, Choong Ki; Yoon, Jong Sup

1989-01-01

There are many method of treatment of the intussusception in children, including surgery, barium reduction, air reduction, and saline enema under ultrasonographic monitoring. Among them, barium reduction and air reduction have been used widely as nonsurgical method of treatment in radiologic department. During barium reduction, the bottle filled with barium solution must not be elevated over a 3 feet from the operating table. In air reduction, diagnostic pressure is about 60 mmHg and pressure during reduction usually is maintained between 90 mmHg and 130 mmHg. The authors have studied about pressure difference of barium solution by changing height of the bottle filled with barium solution, and have compared with pressure in air reduction. The results are as follows; 1. Pressure of 20 w/v % barium solution at the 60 cm height is 44.4 mmHg, and 69.6 mmHg at the 90 cm height. 2. Pressure of 40 w/v % barium solution at the 60 cm height is 51.4 mmHg, and 80.1 mmHg at the 90 cm height. 3. Pressure of 40 w/v % barium solution at the 90cm height is much lower than the pressure maintained during air reduction, and this difference in pressure may be one of the causes of low reduction rate in barium reduction then air reduction. 4. The pressure gradient per 10 cm height is about 8.45 mmHg in 20 w/v % barium solution, about 9.21 mmHg in 30 w/v % barium solution, and about 9.72 mmHg 40 w/v % barium solution. 5. Intraluminal pressure difference between the barium reduction and the air reduction is probably of the major causes of rapid diagnosis and high reduction rate in the air reduction

Barium ion beam. Annual progress report

International Nuclear Information System (INIS)

Lazar, N.; Dandl, R.; Rynn, N.; Wickham, M.

1985-01-01

The barium ion beam Zeeman diagnostic is an in situ nonperturbing diagnostic designed to measure both the plasma electric and magnetic fields in devices such as STM and EBT. The diagnostic satisfies the requirements of high precision, spatial resolution and nonperturbation of the plasma. The technique uses resonance absorption of light from a single moded laser in a beam of energetic barium ions to measure the Zeeman effect in the absorption spectrum (to measure changes in the magnetic field) and to observe the changes in beam velocity by the Doppler shift of the absorption lines

Characterization of Barium Borate Frameworks Using Raman Spectroscopy.

Science.gov (United States)

Gharavi-Naeini, Jafar; Yoo, Kyung W; Stump, Nathan A

2018-04-01

Systematic micro-Raman scattering investigations have been carried out on Sm +2 doped 2(BaO)-n(B 2 O 3 ) matrices for n = 4, 5, 8, and 2(BaO)-(Na 2 O)-9(B 2 O 3 ) using the 364 nm excitation of an Ar + laser. The Raman results have been compared with the known structures of barium tetraborate, barium pentaborate, barium octaborate, and barium sodium nonaborate. An excellent correlation has been found between the BO 4 /BO 3 composition ratios for each product and intensity ratios of the designated BO 4 and BO 3 Raman peaks. Furthermore, the Raman frequencies of both BO 4 and BO 3 groups undergo a systematic blueshift as n increases from four to nine. The shift results from a decrease of the B-O bond lengths for both BO 4 and BO 3 groups as the samples transition from the tetraborate to nonaborate structures. Linear relations (with negative slopes) have been determined between the measured Raman frequencies and B-O bond lengths in the frameworks.

40 CFR 721.10010 - Barium manganese oxide (BaMnO3).

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Barium manganese oxide (BaMnO3). 721... Substances § 721.10010 Barium manganese oxide (BaMnO3). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as barium manganese oxide (BaMnO3) (PMN P-00...

Nanostructured metal sulfides for energy storage

Science.gov (United States)

Rui, Xianhong; Tan, Huiteng; Yan, Qingyu

2014-08-01

Advanced electrodes with a high energy density at high power are urgently needed for high-performance energy storage devices, including lithium-ion batteries (LIBs) and supercapacitors (SCs), to fulfil the requirements of future electrochemical power sources for applications such as in hybrid electric/plug-in-hybrid (HEV/PHEV) vehicles. Metal sulfides with unique physical and chemical properties, as well as high specific capacity/capacitance, which are typically multiple times higher than that of the carbon/graphite-based materials, are currently studied as promising electrode materials. However, the implementation of these sulfide electrodes in practical applications is hindered by their inferior rate performance and cycling stability. Nanostructures offering the advantages of high surface-to-volume ratios, favourable transport properties, and high freedom for the volume change upon ion insertion/extraction and other reactions, present an opportunity to build next-generation LIBs and SCs. Thus, the development of novel concepts in material research to achieve new nanostructures paves the way for improved electrochemical performance. Herein, we summarize recent advances in nanostructured metal sulfides, such as iron sulfides, copper sulfides, cobalt sulfides, nickel sulfides, manganese sulfides, molybdenum sulfides, tin sulfides, with zero-, one-, two-, and three-dimensional morphologies for LIB and SC applications. In addition, the recently emerged concept of incorporating conductive matrices, especially graphene, with metal sulfide nanomaterials will also be highlighted. Finally, some remarks are made on the challenges and perspectives for the future development of metal sulfide-based LIB and SC devices.

Purification of hydrogen sulfide

International Nuclear Information System (INIS)

Tsao, U.

1978-01-01

A process is described for purifying a hydrogen sulfide gas stream containing carbon dioxide, comprising (a) passing the gas stream through a bed of solid hydrated lime to form calcium hydrosulfide and calcium carbonate and (b) regenerating hydrogen sulfide from said calcium hydrosulfide by reacting the calcium hydrosulfide with additional carbon dioxide. The process is especially applicable for use in a heavy water recovery process wherein deuterium is concentrated from a feed water containing carbon dioxide by absorption and stripping using hydrogen sulfide as a circulating medium, and the hydrogen sulfide absorbs a small quantity of carbon dioxide along with deuterium in each circulation

Sulfide oxidation in a biofilter

DEFF Research Database (Denmark)

Pedersen, Claus Lunde; Dezhao, Liu; Hansen, Michael Jørgen

Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

Sulfide oxidation in a biofilter

DEFF Research Database (Denmark)

Pedersen, Claus Lunde; Liu, Dezhao; Hansen, Michael Jørgen

2012-01-01

Observed hydrogen sulfide uptake rates in a biofilter treating waste air from a pig farm were too high to be explained within conventional limits of sulfide solubility, diffusion in a biofilm and bacterial metabolism. Clone libraries of 16S and 18S rRNA genes from the biofilter found no sulfide...... higher hydrogen sulfide uptake followed by oxidation catalyzed by iron-containing enzymes such as cytochrome c oxidase in a process uncoupled from energy conservation....

Radiation losses in microwave K{sub u} region by conducting pyrrole/barium titanate and barium hexaferrite based nanocomposites

Energy Technology Data Exchange (ETDEWEB)

Kaur, Talwinder [Department of Physics, Lovely Professional University, Phagwara 144411 (India); Kumar, Sachin [Department of Chemistry, Guru Nanak Dev University, Amritsar 143005 (India); Narang, S.B. [Department of Electronics Technology, Guru Nanak Dev University, Amritsar 143005 (India); Srivastava, A.K., E-mail: srivastava_phy@yahoo.co.in [Department of Physics, Lovely Professional University, Phagwara 144411 (India)

2016-12-15

Nanocomposites of substituted barium hexaferrite and barium titanate embedded in a polymer were synthesized via emulsion polymerization. The study was performed by using X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy, electron spin resonance spectroscopy, a vibrating sample magnetometer and a vector network analyzer. It is found that maximum radiation loss occur at 16.09 GHz (−14.23 dB) frequency owing to the combined effect of conducting polymer, suitable dielectric and magnetic material. This suggests that prepared material is suitable for radiation losses. Micro structural study reveals the presence of all the phases of the compounds comprises composite. Benzene ring absorption band (at 1183 cm{sup −1}) in FT-IR spectra illustrates the presence of polymer. Surface morphology reveals the presence of array of particles encapsulated by the polymer. - Highlights: • Composites having polymer, barium titanate and hexaferrite have been successfully prepared. • Effective radiation absorption and losses have been achieved. • Magnetic properties have made an impact on shielding effectiveness.

Preparation of porous nano barium ferrite and its adsorption properties on uranium

International Nuclear Information System (INIS)

Xiong Guoxuan; Huang Haiqing; Zhang Zhibin

2012-01-01

The porous nano barium ferrite was made of Fe(NO 3 ) 3 and Ba(NO 3 ) 2 as raw materials, CTAB as surfactant by method of sol-gel and self-propagating combustion. The composition, morphology and magnetic properties of nano-rod barium ferrite were characterized by XRD, SEM and vibrating sample magnetometer. The adsorption properties of porous nano barium ferrite on uranium were studied with static adsorption and the effects of pH, adsorption temperature and oscillation time on adsorption properties were discussed. The results indicate that the average particle size of porous nano barium ferrite is 45-65 nm, the saturation magnetization and coercivity are 62.83 emu/g and 5481.0 Oe, respectively. Under the condition of the porous nano barium ferrite amount of 0.02 g, pH of 6, adsorption temperature of 25℃ and oscillation time of 30 min, the adsorption capacity of uranium on the porous nano barium ferrite reaches 921 μg/g. (authors)

A review of the health impacts of barium from natural and anthropogenic exposure.

Science.gov (United States)

Kravchenko, Julia; Darrah, Thomas H; Miller, Richard K; Lyerly, H Kim; Vengosh, Avner

2014-08-01

There is an increasing public awareness of the relatively new and expanded industrial barium uses which are potential sources of human exposure (e.g., a shale gas development that causes an increased awareness of environmental exposures to barium). However, absorption of barium in exposed humans and a full spectrum of its health effects, especially among chronically exposed to moderate and low doses of barium populations, remain unclear. We suggest a systematic literature review (from 1875 to 2014) on environmental distribution of barium, its bioaccumulation, and potential and proven health impacts (in animal models and humans) to provide the information that can be used for optimization of future experimental and epidemiological studies and developing of mitigative and preventive strategies to minimize negative health effects in exposed populations. The potential health effects of barium exposure are largely based on animal studies, while epidemiological data for humans, specifically for chronic low-level exposures, are sparse. The reported health effects include cardiovascular and kidney diseases, metabolic, neurological, and mental disorders. Age, race, dietary patterns, behavioral risks (e.g., smoking), use of medications (those that interfere with absorbed barium in human organism), and specific physiological status (e.g., pregnancy) can modify barium effects on human health. Identifying, evaluating, and predicting the health effects of chronic low-level and moderate-level barium exposures in humans is challenging: Future research is needed to develop an understanding of barium bioaccumulation in order to mitigate its potential health impacts in various exposured populations. Further, while occupationally exposed at-risk populations exist, it is also important to identify potentially vulnerable subgroups among non-occupationally exposed populations (e.g., elderly, pregnant women, children) who are at higher risk of barium exposure from drinking water and food.

The diagnosis of gastro-esophageal reflux disease cannot be made with barium esophagograms.

Science.gov (United States)

Saleh, C M G; Smout, A J P M; Bredenoord, A J

2015-02-01

For over 50 years, barium studies have been used to diagnose gastro-esophageal reflux disease (GERD), but the value of this test is controversial. Our study aimed to determine if barium esophagograms can be used to diagnose GERD. Barium esophagograms and pH-impedance measurement were performed in 20 subjects with reflux symptoms. pH-impedance measurements were used as gold standard for the diagnosis of GERD. Gastro-esophageal reflux measured with the barium study was defined as a positive outcome. 50% of patients presented gastro-esophageal reflux on the barium esophagogram. No significant differences were observed in acid exposure time between subjects with (median: 7.4%; interquartile range, IQR: 8.4%) or without reflux at barium esophagography (median: 5.95%; IQR: 13.05%; p > 0.05). Nor did we find differences in median proximal extent of reflux measured with impedance monitoring between patients with a positive (median: 6.7%; IQR: 1.95%) and negative barium study (median: 7.1%; IQR: 0.68%; p > 0.05). Patients with reflux on barium esophagogram did not have a positive symptom association probability more often than those who did not have reflux at barium esophagography. Lastly, there were no differences in numbers of acid, weakly acidic or total reflux episodes between those with positive or negative barium esophagogram (p > 0.05). No correlations were found between the maximum proximal extent of gastro-esophageal reflux during esophagography and pH-impedance parameters. Presence or absence of gastro-esophageal reflux during barium esophagography does not correlate with incidence or extent of reflux observed during 24-h pH-impedance monitoring and is not of value for the diagnosis of GERD. © 2014 John Wiley & Sons Ltd.

Contrast characteristics of barium preparations and the timing of exposure

OpenAIRE

渋谷, 光一; 中桐, 義忠; 東, 義晴; 杉田, 勝彦; 小橋, 高郎; 大倉, 保彦; 丹谷, 延義; 三上, 泰隆; 平木, 祥夫

1995-01-01

We studied the relationship between the contrast characteristics of barium suspension and timing of exposure. We poured several kinds of barium preparations on the phantom manufactured by ourselves, and took X-ray pictures continuously by a DSA system. We analyzed each of the characteris-tics of the contrast. The time which was reguired for the contrast to reach the peak (Contrast Peak Time ; CPT) was unrelated with the kind of barium preparations used. It depended on the viscosity of the con...

Outcome of barium enema in patients with colorectal symptoms ...

African Journals Online (AJOL)

Background: For many years, double contrast barium enema has been an effective way to evaluate the large bowel. With the development of the colonoscope, the role of barium enema has been questioned. However it is still useful in investigating patients with colorectal symptoms especially in the developing world where ...

Application of magnesium hydroxide and barium hydroxide for the ...

African Journals Online (AJOL)

Application of magnesium hydroxide and barium hydroxide for the removal of metals and sulphate from mine water. ... equivalent to the Ba(OH)2 dosage. During CO2-dosing, CaCO3 is precipitated to the saturation level of CaCO3. Keywords: Magnesium hydroxide; barium hydroxide; sulphate removal; water treatment ...

49 CFR 173.182 - Barium azide-50 percent or more water wet.

Science.gov (United States)

2010-10-01

... 49 Transportation 2 2010-10-01 2010-10-01 false Barium azide-50 percent or more water wet. 173.182 Section 173.182 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS... Class 1 and Class 7 § 173.182 Barium azide—50 percent or more water wet. Barium azide—50 percent or more...

Barium-borate-flyash glasses: As radiation shielding materials

International Nuclear Information System (INIS)

Singh, Sukhpal; Kumar, Ashok; Singh, Devinder; Thind, Kulwant Singh; Mudahar, Gurmel S.

2008-01-01

The attenuation coefficients of barium-borate-flyash glasses have been measured for γ-ray photon energies of 356, 662, 1173 and 1332 keV using narrow beam transmission geometry. The photon beam was highly collimated and overall scatter acceptance angle was less than 3 o . Our results have an uncertainty of less than 3%. These coefficients were then used to obtain the values of mean free path (mfp), effective atomic number and electron density. Good agreements have been observed between experimental and theoretical values of these parameters. From the studies of the obtained results it is reported here that from the shielding point of view the barium-borate-flyash glasses are better shields to γ-radiations in comparison to the standard radiation shielding concretes and also to the ordinary barium-borate glasses

Charge distributions of barium isotopes from muonic X-rays

International Nuclear Information System (INIS)

Shera, E.B.; Wohlfahrt, H.D.; Hoehn, M.V.; Tanaka, Y.

1982-01-01

The results of a muonic X-ray study of the charge radii of stable barium isotopes are presented and compared with optical isotope shifts. The isotope shifts Δ 2 > of a wide range of barium isotopes are found to be in good agreement with the droplet model and with IBA calculations. (orig.)

BARIUM REDUCTION OF INTUSSUSCEPTION IN INFANCY

Science.gov (United States)

Denenholz, Edward J.; Feher, George. S.

1955-01-01

Barium enema reduction was used as the initial routine treatment in 29 infants with intussusception. In 22 of them the intussusception was reduced by this means. In three of eight patients operated upon the intussusception was found to be reduced. Four of the remaining five patients had clinical or x-ray evidence of complications before reduction by barium enema was attempted. Twenty-one of the patients, all of whom were observed in private practice, were treated without admission to the hospital. After reduction, these patients were observed closely by the clinician. None of these patients showed clinical or x-ray signs of complications before reduction. Certain clinical and roentgen criteria must be satisfied before it can be concluded that reduction by barium enema is complete. If there are clinical signs of complications with x-ray evidence of small bowel obstruction, only a very cautious attempt at hydrostatic reduction should be made. As the time factor is generally a reliable clinical guide to reducibility, the late cases should be viewed with greater caution. Long duration of symptoms, however, is not per se a contraindication to an attempt at hydrostatic reduction. PMID:13230908

Making of Magnet Barium Ferit Anisotropic

International Nuclear Information System (INIS)

Idayati, Novrita; Dedi

2003-01-01

Barium Hexa ferrite (BaFe 12 O 19 ) is ceramic and materials which usually used for making of permanent magnet. In this research Barium Hexa ferrite were made Anisotropic, and applied for loudspeaker, electro motors, dynamo, KWh metre, etc. this Magnet is commonly used due to its high Induction of Remanen (Br) and coercivity (high Hc). Besides it applies a more simple and easier process technology, cheaper raw material, and easy to find it, hence the magnetic component is much cheaper. Powder Metallurgy was used for the process technology, by reacting all materials in the powder (oxide), with a certain size distribution and a tight preparation step. The next step was mixing ferrite and Barium Carbonate (in the form of oxide), calcination, compaction, cantering and characterisation. The Anisotropic particle effects a high Induce Remanen (Br) and of koersifitas (high Hc). All the process steps will is determine physical and chemical characteristics of the magnet. The best Magnet characteristic of the magnet produced in this research is Induction of Remanen (Br) = 4,27 kg, Coercivity (Hc) = 1,745 kOe, Energy Product max (BHmaks) = 2,31 MGOe

Thermal reactions of some calcium, strontium, and barium chromates

International Nuclear Information System (INIS)

Piekarska-Piesse, B.; Gontarz, Z.; Ostrowski, A.; Kucharski, R.

2000-01-01

Thermal decomposition of calcium chromates and solid state reactions of barium and strontium chromates(VI) with barium and strontium hydroxides and carbonates, as well as the reduction of chromates by carbon and hydrogen, have been investigated. The mechanisms of individual stages of the thermal decomposition have been proposed on the basis of morphological classification. (author)

Barium and radium radiopolarography

International Nuclear Information System (INIS)

Fourest, B.

1979-01-01

Radiopolarography has been applied to the study of two elements (barium and radium) which is difficult by classical polarography because of their strong electropositivity. Various parameters have been considered: nature, concentration and pH of supporting electrolyte. In any case of investigated mediums, the reduction to the metallic state reaction appeared to be reversible. An important variation of the barium half-wave potential E 1/2 with the ionic strength μ of the solution, imposed by LiCl used as supporting electrolyte, has been observed. It gives the possibility to estimate, for μ = 0, E 1/2 (Ba) = - 1.916 V/S.C.E. and E 1/2(Ra) = - 1.852 V/S.C.E. The values of barium and radium half wave potentials, obtained with a good accuracy in LiCl (or LiClO 4 ) 0.1 M medium, have been used to establish the amalgamation energy Δ 2 (M) of these elements. A linear variation of Δ 2 (M) with the metallic radius of the 2a elements has been obtained. On the other hand, by making the concentration of the complex forming agent (Cit 3- ) vary in the solution, we have a shift in the half wave potential from which we can deduce the stability constant of the complexe and its composition (BaCit - ; pK 1 =2). At last, nature and concentration of the supporting electrolyte (between 5.10 -2 M and 5M) have a determining influence on the extent of the polarogram plateau. This plateau is limited by an 'hollow effect' preceding the supporting electrolyte discharge. An interpretation of this effect is suggested which is based on the Stern model [fr

Microbial control of hydrogen sulfide production

Energy Technology Data Exchange (ETDEWEB)

Montgomery, A.D.; Bhupathiraju, V.K.; Wofford, N.; McInerney, M.J. [Univ. of Oklahoma, Tulsa, OK (United States)] [and others

1995-12-31

A sulfide-resistant strain of Thiobacillus denitrificans, strain F, prevented the accumulation of sulfide by Desulfovibrio desulfuricans when both organisms were grown in liquid medium. The wild-type strain of T. denitrificans did not prevent the accumulation of sulfide produced by D. desulfuricans. Strain F also prevented the accumulation of sulfide by a mixed population of sulfate-reducing bacteria enriched from an oil field brine. Fermentation balances showed that strain F stoichiometrically oxidized the sulfide produced by D. desulfuricans and the oil field brine enrichment to sulfate. The ability of a strain F to control sulfide production in an experimental system of cores and formation water from the Redfield, Iowa, natural gas storage facility was also investigated. A stable, sulfide-producing biofilm was established in two separate core systems, one of which was inoculated with strain F while the other core system (control) was treated in an identical manner, but was not inoculated with strain F. When formation water with 10 mM acetate and 5 mM nitrate was injected into both core systems, the effluent sulfide concentrations in the control core system ranged from 200 to 460 {mu}M. In the test core system inoculated with strain F, the effluent sulfide concentrations were lower, ranging from 70 to 110 {mu}M. In order to determine whether strain F could control sulfide production under optimal conditions for sulfate-reducing bacteria, the electron donor was changed to lactate and inorganic nutrients (nitrogen and phosphate sources) were added to the formation water. When nutrient-supplemented formation water with 3.1 mM lactate and 10 mM nitrate was used, the effluent sulfide concentrations of the control core system initially increased to about 3,800 {mu}M, and then decreased to about 1,100 {mu}M after 5 weeks. However, in the test core system inoculated with strain F, the effluent sulfide concentrations were much lower, 160 to 330 {mu}M.

Status of barium studies in the present era of oncology: Are they a history?

Science.gov (United States)

Mahajan, Abhishek; Desai, Subash; Sable, Nilesh Pandurang; Thakur, Meenakshi Haresh

2016-01-01

With the advent of the modern imaging technologies, the present era of oncology is seeing steady decline in requests for barium studies due to the many reasons. It is prudent to mention here, that, barium examinations cannot be made obsolete! Our aim to preserve the age old technique of barium studies not only to keep it going on but also for the betterment and appropriate management of the patient. Our goal is not to "save" barium studies simply to keep this technology alive, per se, but rather to preserve barium radiology for the quality in patient care.

Role of Barium Swallow in Diagnosing Clinically Significant Anastomotic Leak following Esophagectomy

Directory of Open Access Journals (Sweden)

Simon Roh

2016-04-01

Full Text Available Background: Barium swallow is performed following esophagectomy to evaluate the anastomosis for detection of leaks and to assess the emptying of the gastric conduit. The aim of this study was to evaluate the reliability of the barium swallow study in diagnosing anastomotic leaks following esophagectomy. Methods: Patients who underwent esophagectomy from January 2000 to December 2013 at our institution were investigated. Barium swallow was routinely done between days 5–7 to detect a leak. These results were compared to clinically determined leaks (defined by neck wound infection requiring jejunal feeds and or parenteral nutrition during the postoperative period. The sensitivity and specificity of barium swallow in diagnosing clinically significant anastomotic leaks was determined. Results: A total of 395 esophagectomies were performed (mean age, 62.2 years. The indications for the esophagectomy were as follows: malignancy (n=320, high-grade dysplasia (n=14, perforation (n=27, benign stricture (n=7, achalasia (n=16, and other (n=11. A variety of techniques were used including transhiatal (n=351, McKeown (n=35, and Ivor Lewis (n=9 esophagectomies. Operative mortality was 2.8% (n=11. Three hundred and sixty-eight patients (93% underwent barium swallow study after esophagectomy. Clinically significant anastomotic leak was identified in 36 patients (9.8%. Barium swallow was able to detect only 13/36 clinically significant leaks. The sensitivity of the swallow in diagnosing a leak was 36% and specificity was 97%. The positive and negative predictive values of barium swallow study in detecting leaks were 59% and 93%, respectively. Conclusion: Barium swallow is an insensitive but specific test for detecting leaks at the cervical anastomotic site after esophagectomy.

Studies on phase evolution and electrical conductivity of barium doped gadolinium aluminate

International Nuclear Information System (INIS)

Sinha, Amit; Sharma, B.P.; Gopalan, P.

2012-01-01

Highlights: ► Barium doped GdAlO 3 compositions were prepared from citrate gel derived powders. ► The solid solubility of barium in GdAlO 3 was less than 4 mol%. ► The un-dissolved barium precipitated in the form of BaAl 2 O 4 phase. ► The conductivity of Ba-doped GdAlO 3 increased with increasing amounts of Ba. ► In Gd 1−x Ba x AlO 3−δ system, specimen with x = 0.02 exhibited maximum conductivity. - Abstract: The phase evolution and electrical conductivity of barium doped GdAlO 3 samples have been investigated. The Ba- doped compositions of GdAlO 3 were prepared through citrate gel process. Analysis of the phases was carried out using X-ray diffraction (XRD). The morphology of the calcined powders was studied by scanning electron microscopy. The electrical conductivity of Gd 1−x Ba x AlO 3−δ (x = 0–0.04) was measured using ac impedance spectroscopy as a function of temperature ranging from 300 to 1000 °C under air. The solid solubility of barium in GdAlO 3 was found to be less than 4 mol%. The undissolved barium precipitated in the form of BaAl 2 O 4 phase. The barium doped GdAlO 3 powders obtained after calcination at 1000 °C was found to be porous agglomerate composed of nanocrystalline grains. The total electrical conductivity of Ba-doped GdAlO 3 increased with increasing amounts of barium up to 2 mol% doping.

The diagnosis of gastro-esophageal reflux disease cannot be made with barium esophagograms

NARCIS (Netherlands)

Saleh, C. M. G.; Smout, A. J. P. M.; Bredenoord, A. J.

2015-01-01

For over 50 years, barium studies have been used to diagnose gastro-esophageal reflux disease (GERD), but the value of this test is controversial. Our study aimed to determine if barium esophagograms can be used to diagnose GERD. Barium esophagograms and pH-impedance measurement were performed in 20

Mesostructured metal germanium sulfides

Energy Technology Data Exchange (ETDEWEB)

MacLachlan, M.J.; Coombs, N.; Bedard, R.L.; White, S.; Thompson, L.K.; Ozin, G.A.

1999-12-29

A new class of mesostructured metal germanium sulfide materials has been prepared and characterized. The synthesis, via supramolecular assembly of well-defined germanium sulfide anionic cluster precursors and transition-metal cations in formamide, represents a new strategy for the formation of this class of solids. A variety of techniques were employed to examine the structure and composition of the materials. Structurally, the material is best described as a periodic mesostructured metal sulfide-based coordination framework akin to periodic hexagonal mesoporous silica, MCM-41. At the molecular scale, the materials strongly resemble microstructured metal germanium sulfides, in which the structure of the [Ge{sub 4}S{sub 10}]{sup 4{minus}} cluster building-blocks are intact and linked via {mu}-S-M-S bonds. Evidence for a metal-metal bond in mesostructured Cu/Ge{sub 4}S{sub 10} is also provided.

Barium contributions to the valence electronic structure of YBa2Cu3O7-δ, PrBa2Cu3O7-δ, and other barium-containing compounds

International Nuclear Information System (INIS)

Mueller, D.R.; Wallace, J.S.; Jia, J.J.; O'Brien, W.L.; Dong, Q.; Callcott, T.A.; Miyano, K.E.; Ederer, D.L.

1995-01-01

Monochromatic photon beams were used to excite barium N IV,V soft x-ray emission spectra from YBa 2 Cu 3 O 7-δ , PrBa 2 Cu 3 O 7-δ , BaF 2 , and BaTiO 3 . Near threshold excitation was used to demonstrate that small contributions to the barium N V and N IV emission spectra in the energy region above the 5p→4d core-core transitions do not arise as satellite emission from transitions in multiply excited atoms but rather occur as a result of transitions from the valence states. The emission spectrum of YBa 2 Cu 3 O 7-δ and PrBa 2 Cu 3 O 7-δ reveals a contribution to the electronic density of states at the barium site in the region near the Fermi level. The YBa 2 Cu 3 O 7-δ compound is a superconductor and PrBa 2 Cu 3 O 7-δ is an insulator. It has been proposed that the difference between them is due to mixing of praseodymium and barium among the sites occupied by yttrium and barium, with an accompanying change in electronic structure. However, our measurements indicate that the barium partial density of states for the two compounds are essentially identical

Synthesis and properties of barium diketonates as precursors for MOCVD

Energy Technology Data Exchange (ETDEWEB)

Drozdov, A.A. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Troyanov, S.I. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Kuzmina, N.P. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Martynenko, L.I. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Alikhanyan, A.S. (Dept. of Chemistry, Moscow State Univ. (Russian Federation)); Malkerova, I.P. (Dept. of Chemistry, Moscow State Univ. (Russian Federation))

1993-08-01

The structures of barium diketonates depend on the way in which they are synthesized. It is shown that there is a correlation between the volatility of these compounds and their crystal structures. A new volatile mononuclear adduct of barium dipivaloylmethanate suitable for MOCVD is suggested. (orig.).

Synthesis and properties of barium diketonates as precursors for MOCVD

International Nuclear Information System (INIS)

Drozdov, A.A.; Troyanov, S.I.; Kuzmina, N.P.; Martynenko, L.I.; Alikhanyan, A.S.; Malkerova, I.P.

1993-01-01

The structures of barium diketonates depend on the way in which they are synthesized. It is shown that there is a correlation between the volatility of these compounds and their crystal structures. A new volatile mononuclear adduct of barium dipivaloylmethanate suitable for MOCVD is suggested. (orig.)

Barium hexaferrite nanoparticles: Synthesis and magnetic properties

International Nuclear Information System (INIS)

Martirosyan, K.S.; Galstyan, E.; Hossain, S.M.; Wang Yiju; Litvinov, D.

2011-01-01

Carbon combustion synthesis is applied to rapid and energy efficient fabrication of crystalline barium hexaferrite nanoparticles with the average particle size of 50-100 nm. In this method, the exothermic oxidation of carbon nanoparticles with an average size of 5 nm with a surface area of 80 m 2 /g generates a self-propagating thermal wave with maximum temperatures of up to 1000 deg. C. The thermal front rapidly propagates through the mixture of solid reactants converting it to the hexagonal barium ferrite. Carbon is not incorporated in the product and is emitted from the reaction zone as a gaseous CO 2 . The activation energy for carbon combustion synthesis of BaFe 12 O 19 was estimated to be 98 kJ/mol. A complete conversion to hexagonal barium ferrite is obtained for carbon concentration exceeding 11 wt.%. The magnetic properties H c ∼3000 Oe and M s ∼50.3 emu/g of the compact sintered ferrites compare well with those produced by other synthesis methods.

Diagnostic role of barium enema in carcinoma rectum

International Nuclear Information System (INIS)

Asghar, M.

2003-01-01

Objective: The main aim of this barium enema study was to evaluate its role in patients suspected to have rectal pathologies with complaints of change in bowel habit, anorexia/weight loss, bleeding per rectum and acute/sub-acute colonic obstruction. Results: barium enema study as screening test for colo-rectal carcinoma was undertaken. Contrast outlined the colonic growth in 35 cases, out of which the cases of carcinoma colon were 24 including 13 patients suffering from carcinoma rectum. The percentage of carcinoma colon to total colonic growth was 68% while, carcinoma rectum to total carcinoma colon was 54%. Conclusion: On the basis of these investigations, it is concluded that patient's compliance is important factor in the early detection of colonic neoplasia. Though results of colonoscopy are more reliable but in practice, barium enema (double contrast) is performed initially to outline the lesion and then colonoscopy for biopsy purpose. (author)

Atomization of magnesium, strontium, barium and lead nitrates on surface of graphite atomizers

International Nuclear Information System (INIS)

Nagdaev, V.K.; Pupyshev, A.A.

1982-01-01

Modelling of the processes on graphite surface using differential-thermal analysis and graphite core with identification of decomposition products of magnesium, strontium, barium and lead nitrates by X-ray analysis has shown that carbon promotes the formation of strontium, barium and lead carbonates. The obtained temperatures of strontium and barium carbonate decomposition to oxides agree satisfactorily with calculation ones. Magnesium nitrate does not react with carbon. Formation of strontium and barium carbonates results in considerable slowing down of the process of gaseous oxide dissociation. Lead carbonate is unstable and rapidly decomposes to oxide with subsequent reduction to free metal. Formation of magnesium, strontium and barium free atoms is connected with appearance of gaseous oxides in analytical zone. Oxide and free metal lead are present on graphite surface simultaneously

Aspiration of barium contrast medium in an elderly man with disordered swallowing

OpenAIRE

Bağcı Ceyhan, B.; Çelikel, T.; Koç, M.; Ahıskalı, R.; Biren, T.; Ataizi Çelikel, Ç.

1995-01-01

The aspiration of contrast medium during the investigation of gastrointestinal diseases is a well recognized hazard, particularly in patients with swallowing disorders. A case is reported in which accidental aspiration of contrast barium occurred owing to disordered swallowing in an elderly man. The infiltration on chest x-ray persisted 2 years after barium contrast aspiration. Inflammatory reaction and retractile, granular material observed in lung biopsy specimens suggested barium-induced p...

Synthesis and surface properties of submicron barium sulfate particles

International Nuclear Information System (INIS)

Zhang Ming; Zhang Bao; Li Xinhai; Yin Zhoulan; Guo Xueyi

2011-01-01

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO 4 particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO 4 particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO 4 were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO 4 was presented. The FTIR result indicates that the surface of the prepared BaSO 4 absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

Synthesis and surface properties of submicron barium sulfate particles

Energy Technology Data Exchange (ETDEWEB)

Zhang Ming, E-mail: csu.light@yahoo.com.cn [College of Chemistry and Chemical Engineering, Zhaoqing University, Zhaoqing 526061 (China); School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Zhang Bao; Li Xinhai [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); Yin Zhoulan [School of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Guo Xueyi [School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China)

2011-10-15

Barium sulfate particles were synthesized in the presence of EDTA at room temperature. X-ray diffractometry (XRD), Fourier transform infrared resonance (FTIR) and scanning electron microscopy (SEM) were used to characterize the structure and morphology of BaSO{sub 4} particles. The effect of the preparation parameters on the particle size distribution and morphology was investigated. The conditional formation constants of Ba-EDTA at different pH values were calculated. The results show that the size and morphology of BaSO{sub 4} particles can be effectively controlled by adding EDTA in the precipitation process. Among all the operation conditions, the pH value has significant effect on the particle size. The obtained barium sulfate particles are spherical and well dispersed at pH = 9-10. Zeta potentials of BaSO{sub 4} were measured at different pH. The isoelectric point (IEP) of barium sulfate colloid appears at pH 6.92. The model of the solid-solution interface at a particle of BaSO{sub 4} was presented. The FTIR result indicates that the surface of the prepared BaSO{sub 4} absorbs the functional groups of EDTA, which lower the IEP of the barium sulfate particles.

Prospective comparison of double contrast barium enema plus flexible sigmoidoscopy v colonoscopy in rectal bleeding: barium enema v colonoscopy in rectal bleeding.

OpenAIRE

Irvine, E J; O'Connor, J; Frost, R A; Shorvon, P; Somers, S; Stevenson, G W; Hunt, R H

1988-01-01

Rectal bleeding often heralds serious colonic disease. The literature suggests that colonoscopy is superior to barium enema plus sigmoidoscopy, although no good comparative studies exist. Seventy one patients with overt rectal bleeding had prospectively flexible sigmoidoscopy, double contrast barium enema and colonoscopy completed independently. Against the gold standard, the sensitivity and specificity of colonoscopy were 0.69 and 0.78 respectively for a spectrum of colonic lesions, while fo...

Printed Barium Strontium Titanate capacitors on silicon

Energy Technology Data Exchange (ETDEWEB)

Sette, Daniele [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Luxembourg Institute of Science and Technology LIST, Materials Research and Technology Department, L-4422 Belvaux (Luxembourg); Kovacova, Veronika [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Defay, Emmanuel, E-mail: emmanuel.defay@list.lu [Univ. Grenoble Alpes, F-38000 Grenoble (France); CEA, LETI, MINATEC Campus, F-38054 Grenoble (France); Luxembourg Institute of Science and Technology LIST, Materials Research and Technology Department, L-4422 Belvaux (Luxembourg)

2015-08-31

In this paper, we show that Barium Strontium Titanate (BST) films can be prepared by inkjet printing of sol–gel precursors on platinized silicon substrate. Moreover, a functional variable capacitor working in the GHz range has been made without any lithography or etching steps. Finally, this technology requires 40 times less precursors than the standard sol–gel spin-coating technique. - Highlights: • Inkjet printing of Barium Strontium Titanate films • Deposition on silicon substrate • Inkjet printed silver top electrode • First ever BST films thinner than 1 μm RF functional variable capacitor that has required no lithography.

Rapid and accurate determination of barium by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Armelin, Maria Jose A.; Maihara, Vera A.; Saiki, Mitiko; Trevizam, Anderson R.

2013-01-01

Barium is an alkaline earth metal naturally present in soils. When available at a high level in the soil it can cause toxicity to plants and animals. Not all the barium is readily available to living organisms. Inorganic and organic barium compounds can be presented as soluble or insoluble forms in the soil. The soluble form of BaS is extremely toxic to humans, animals and plants. Researchers have noted a decrease of K absorption in the plant when Ba concentrations are increased and a change in overall plant growth. In case of animals, Ba tends to be concentrated in the bones which may compete with calcium, although only about 2% barium ingested in dietary is absorbed by the body. Another effect is that the Ba can interfere with the availability of sulfur in the soil due to the sulphate formation of low solubility. Barium and some other elements are considered palioclimatic proxies. For some researchers, barite is perhaps the most appropriate indicator of paleoproductivity because of a high resistance to dissolution. As explained about the barium effects in various situations, it was considered important to study the more appropriated experimental conditions for determination of this element by INAA. Conditions established for this analysis were: a) Irradiation time, 15 and 40 seconds, under thermal flux neutron about 4 x 10 12 n cm -2 s -1 , for determining barium in geological and biological matrices, respectively; b) Decay time, approximately of 4 minutes; c) Counting time of 30 minutes; d) Radionuclide measured 139 Ba. The quality of Ba results was evaluated from the analysis of certified reference materials. The performance of the method was satisfactory, according to the criterion of E.ζ score. Results obtained in this study indicate INAA is a good alternative for Ba determination in geological and biological samples. (author)

Air-water transfer of hydrogen sulfide

DEFF Research Database (Denmark)

Yongsiri, C.; Vollertsen, J.; Rasmussen, M. R.

2004-01-01

The emissions process of hydrogen sulfide was studied to quantify air–water transfer of hydrogen sulfide in sewer networks. Hydrogen sulfide transfer across the air–water interface was investigated at different turbulence levels (expressed in terms of the Froude number) and pH using batch...... experiments. By means of the overall mass–transfer coefficient (KLa), the transfer coefficient of hydrogen sulfide (KLaH2S), referring to total sulfide, was correlated to that of oxygen (KLaO2) (i.e., the reaeration coefficient). Results demonstrate that both turbulence and pH in the water phase play...... a significant role for KLaH2S. An exponential expression is a suitable representation for the relationship between KLaH2S and the Froude number at all pH values studied (4.5 to 8.0). Because of the dissociation of hydrogen sulfide, KLaH2S increased with decreasing pH at a constant turbulence level. Relative...

TV observations of the Barium-GEOS ion jet experiment

International Nuclear Information System (INIS)

Hapgood, M.A.; Collin, H.L.; Rothwell, P.

1980-01-01

The barium jet released by the Barium-GEOS rocket was observed by low light television cameras at Skibotn, Norway and Esrange, Sweden. The release produced a single well-defined jet containing barium ions with initial velocities between 7 and 12 km s -1 systematically slower than the velocities reported in previous experiments. Accurate data on the motion of the jet has been obtained for the first two minutes after release (up to a height of 2000 km). The orientation of the jet was close to that of an IGRF1975 model field line but was significantly different from that predicted by the Barraclough and Olson field model. The motion of the jet across the field lines was southwards with a velocity of about 150 m s -1 . (Auth.)

Barium titanate thick films prepared by screen printing technique

Directory of Open Access Journals (Sweden)

Mirjana M. Vijatović

2010-06-01

Full Text Available The barium titanate (BaTiO3 thick films were prepared by screen printing technique using powders obtained by soft chemical route, modified Pechini process. Three different barium titanate powders were prepared: i pure, ii doped with lanthanum and iii doped with antimony. Pastes for screen printing were prepared using previously obtained powders. The thick films were deposited onto Al2O3 substrates and fired at 850°C together with electrode material (silver/palladium in the moving belt furnace in the air atmosphere. Measurements of thickness and roughness of barium titanate thick films were performed. The electrical properties of thick films such as dielectric constant, dielectric losses, Curie temperature, hysteresis loop were reported. The influence of different factors on electrical properties values was analyzed.

Effects of powdered versus liquid barium on the viscosity of fluids used in modified swallow studies

International Nuclear Information System (INIS)

Baron, J.; Alexander, T.

2003-01-01

To determine if the viscosity of thickened juice mixtures used in modified barium swallow studies significantly changes with the addition of powdered barium. We also describe a test formulation created using liquid barium, which has a negligible effect on juice viscosity. The viscosities of water and standardized honey- and nectar-consistency juices mixed with different amounts of powdered barium were measured by timing the laminar flow of a given initial hydrostatic head of fluid under gravity though an orifice of fixed diameter. Standardized juices were then mixed with a liquid formulation of barium and with measured quantities of water to produce viscosities that more closely equated with those of the standardized juices. With the addition of powdered barium, viscosity increased in all fluids, most markedly with the nectar-consistency juice. Liquid barium formulations maintained the viscosities of the original thickened juices. Rendering juices radio-opaque with barium powder results in dramatic increases in the viscosity of the resulting mixture and compromises diagnostic accuracy. Liquid barium preparations have the advantage that they can be rapidly and accurately dispensed by syringe, and their use does not significantly increase the viscosity of the preparation. (author)

Effects of powdered versus liquid barium on the viscosity of fluids used in modified swallow studies

Energy Technology Data Exchange (ETDEWEB)

Baron, J.; Alexander, T. [Univ. of Alberta, Dept. of Radiology, Edmonton, Alberta (Canada)

2003-06-01

To determine if the viscosity of thickened juice mixtures used in modified barium swallow studies significantly changes with the addition of powdered barium. We also describe a test formulation created using liquid barium, which has a negligible effect on juice viscosity. The viscosities of water and standardized honey- and nectar-consistency juices mixed with different amounts of powdered barium were measured by timing the laminar flow of a given initial hydrostatic head of fluid under gravity though an orifice of fixed diameter. Standardized juices were then mixed with a liquid formulation of barium and with measured quantities of water to produce viscosities that more closely equated with those of the standardized juices. With the addition of powdered barium, viscosity increased in all fluids, most markedly with the nectar-consistency juice. Liquid barium formulations maintained the viscosities of the original thickened juices. Rendering juices radio-opaque with barium powder results in dramatic increases in the viscosity of the resulting mixture and compromises diagnostic accuracy. Liquid barium preparations have the advantage that they can be rapidly and accurately dispensed by syringe, and their use does not significantly increase the viscosity of the preparation. (author)

Complications from radiographer-performed double contrast barium enemas

Energy Technology Data Exchange (ETDEWEB)

Vora, P.; Chapman, A. E-mail: anthony.chapman@leedsth.nhs.uk

2004-04-01

AIM: To determine the types and rates of complications encountered by radiographers when performing double contrast barium enemas (DCBE). MATERIALS AND METHODS: Seven hundred and forty-one questionnaires were posted to radiographers who had in the last 5 years attended one of the biannual barium enema training courses. RESULTS: Of 741 questionnaires posted 407 (54.9%) were returned completed. Approximately 348,000 barium enema examinations had been performed. Fifty-nine radiographers reported 89 complications, including 13 intra-peritoneal and 11 extra-peritoneal perforations. There were five deaths (mortality 1 in 70,000). Deaths resulted from two of 24 (10%) perforations, two of 45 (5%) cardiac events and one cerebrovascular accident that occurred during an examination. CONCLUSIONS: Radiographers have been regularly performing DCBEs for almost a decade. The mortality for radiographer-performed DCBE is similar to that previously reported for radiologists, although a slightly higher rate of perforation is noted and so this is an area where radiographer training should be targeted.

Complications from radiographer-performed double contrast barium enemas

International Nuclear Information System (INIS)

Vora, P.; Chapman, A.

2004-01-01

AIM: To determine the types and rates of complications encountered by radiographers when performing double contrast barium enemas (DCBE). MATERIALS AND METHODS: Seven hundred and forty-one questionnaires were posted to radiographers who had in the last 5 years attended one of the biannual barium enema training courses. RESULTS: Of 741 questionnaires posted 407 (54.9%) were returned completed. Approximately 348,000 barium enema examinations had been performed. Fifty-nine radiographers reported 89 complications, including 13 intra-peritoneal and 11 extra-peritoneal perforations. There were five deaths (mortality 1 in 70,000). Deaths resulted from two of 24 (10%) perforations, two of 45 (5%) cardiac events and one cerebrovascular accident that occurred during an examination. CONCLUSIONS: Radiographers have been regularly performing DCBEs for almost a decade. The mortality for radiographer-performed DCBE is similar to that previously reported for radiologists, although a slightly higher rate of perforation is noted and so this is an area where radiographer training should be targeted

Barium fluoride surface preparation, analysis and UV reflective coatings at Lawrence Livermore National Laboratory

International Nuclear Information System (INIS)

Wuest, C.R.

1992-01-01

Lawrence Livermore National Laboratory (LLNL) has begun a program of study on barium fluoride scintillating crystals for the Barium Fluoride Electromagnetic Calorimeter Collaboration. This program has resulted in a number of significant improvements in the mechanical processing, polishing and coating of barium fluoride crystals. Techniques have been developed using diamond-loaded pitch lapping that can produce 15 angstrom RMS surface finishes over large areas. These lapped surfaces have been shown to be crystalline using Rutherford Back-scattering (RBS). Also, special polishing fixtures have been designed based on mounting technology developed for the 1.1 m diameter optics used in LLNL's Nova Laser. These fixtures allow as many as five 25--50 cm long barium fluoride crystals to be polished and lapped at a time with the necessary tolerances for the 16,000 crystal Barium Fluoride Calorimeter. In addition, results will be presented on coating barium fluoride with UV reflective layers of magnesium fluoride and aluminum

Sulfidation behavior of Fe20Cr alloys

International Nuclear Information System (INIS)

Pillis, Marina Fuser

2001-01-01

Alloys for use in high temperature environments rely on the formation of an oxide layer for their protection. Normally, these protective oxides are Cr 2 O 3 , Al 2 O 3 and, some times, SiO 2 . Many industrial gaseous environments contain sulfur. Sulfides, formed in the presence of sulfur are thermodynamically less stable, have lower melting points and deviate much more stoichiometrically, compared to the corresponding oxides. The mechanism of sulfidation of various metals is as yet not clear, in spite of the concerted efforts during the last decade. To help address this situation, the sulfidation behavior of Fe20Cr has been studied as a function of compositional modifications and surface state of the alloy. The alloys Fe20Cr, Fe20Cr0.7Y, Fe20Cr5Al and Fe20Cr5Al0.6Y were prepared and three sets of sulfidation tests were carried out. In the first set, the alloys were sulfidized at 700 deg C and 800 deg C for 10h. In the second set, the alloys were pre-oxidized at 1000 deg C and then sulfidized at 800 deg C for up to 45h. In the third set of tests, the initial stages of sulfidation of the alloys was studied. All the tests were carried out in a thermobalance, in flowing H 2 /2%H 2 S, and the sulfidation behavior determined as mass change per unit area. Scanning electron microscopy coupled to energy dispersive spectroscopy and X-ray diffraction analysis were used to characterize the reaction products. The addition of Y and Al increased sulfidation resistance of Fe20Cr. The addition of Y altered the species that diffused predominantly during sulfide growth. It changed from predominant cationic diffusion to predominant anionic diffusion. The addition of Al caused an even greater increase in sulfidation resistance of Fe20Cr, with the parabolic rate constant decreasing by three orders of magnitude. Y addition to the FeCrAl alloy did not cause any appreciable alteration in sulfidation resistance. Pre-oxidation of the FeCrAl and FeCrAlY alloys resulted in an extended

Results of a cooperative study for the evaluation of the barium meal Falibaryt HD

International Nuclear Information System (INIS)

Reisinger, W.; Liess, G.; Beckmann, D.; Block, H.G.; Dietze, R.; Grosche, N.; Hall, E.; Lasch, G.; Knoth, H.J.; Kroeger, W.

1986-01-01

The diagnostic capabilities of radiologic investigations of the stomach in double contrast can be significantly improved with high-density low-viscosity barium meals. In the GDR the barium meal Falibaryt HD with a barium sulfate content of 215 g per 100 ml suspension has been developed. In nearly 1,000 radiologic investigations of the stomach (81% in relaxation with spasmolytics, 66% without hypotony) all fine structures were well imaged and the preparation therefore is comparable with the best barium meals presently on the market. (author)

Colonoscopy can miss diverticula of the left colon identified by barium enema.

Science.gov (United States)

Niikura, Ryota; Nagata, Naoyoshi; Shimbo, Takuro; Akiyama, Junichi; Uemura, Naomi

2013-04-21

To identify the diagnostic value of colonoscopy for diverticulosis as determined by barium enema. A total of 65 patients with hematochezia who underwent colonoscopy and barium enema were analyzed, and the diagnostic value of colonoscopy for diverticula was assessed. The receiver operating characteristic area under the curve was compared in relation to age (barium enema. Colonoscopy had a sensitivity of 91% and specificity of 90%. No significant differences were found in the receiver operating characteristic area under the curve (ROC-AUC) for age group or sex. The ROC-AUC of the left colon was significantly lower than that of the right colon (0.81 vs 0.96, P = 0.02). Colonoscopy identified 486 colonic diverticula, while barium enema identified 1186. The detection ratio for the entire colon was therefore 0.41 (486/1186). The detection ratio in the left colon (0.32, 189/588) was significantly lower than that of the right colon (0.50, 297/598) (P barium enema, only half the number of colonic diverticula can be detected by colonoscopy in the entire colon and even less in the left colon.

Experimental studies on 3D printing of barium titanate ceramics for medical applications

Directory of Open Access Journals (Sweden)

Schult Mark

2016-09-01

Full Text Available The present work deals with the 3D printing of porous barium titanate ceramics. Barium titanate is a biocompatible material with piezoelectric properties. Due to insufficient flowability of the starting material for 3D printing, the barium titanate raw material has been modified in three different ways. Firstly, barium titanate powder has been calcined. Secondly, flow additives have been added to the powder. And thirdly, flow additives have been added to the calcined powder. Finally, a polymer has been added to the three materials and specimens have been printed from these three material mixtures. The 3D printed parts were then sintered at 1320°C. The sintering leads to shrinkage which differs between 29.51–71.53% for the tested material mixtures. The porosity of the parts is beneficial for cell growth which is relevant for future medical applications. The results reported in this study demonstrate the possibility to fabricate porous piezoelectric barium titanate parts with a 3D printer that can be used for medical applications. 3D printed porous barium titanate ceramics can especially be used as scaffold for bone tissue engineering, where the bone formation can be promoted by electrical stimulation.

Barium ionization mechanisms in the CRRES G-1 and G-11b releases

International Nuclear Information System (INIS)

Hunton, D.E.

1993-01-01

The G-11b chemical release experiment form the Combined Release and Radiation Effects Satellite (CRRES) was conducted in darkness below the solar UV terminator to test the Critical Ionization Velocity (CIV) hypothesis. The Quadrupole Ion Mass Spectrometer (QIMS) aboard CRRES measured fluxes of barium ions from this darkness release that were only a factor of ten smaller than the G-1 release measurements in full sunlight. Possible mechanisms for this significant barium ionization in darkness include CIV, charge exchange with O + , collisional ionization and associative ionization. The authors have evaluated the relative contributions of the collisional mechanisms by constructing a simple model of barium ions from the darkness release seem to be consistent with recent measurements of the charge transfer cross section. A collective plasma ionization mechanism such as CIV does not seem to necessary in order to explain the large barium ion fluxes observed. However, QIMS could only detect barium ions formed several seconds after the initial detonation of the release canister. A CIV process could still have occurred very early in the expansion of the barium neutral cloud and the mass spectrometer would not have detected these ions

Sulfide intrusion and detoxification in seagrasses ecosystems

DEFF Research Database (Denmark)

Hasler-Sheetal, Harald; Holmer, Marianne

Sulfide intrusion in seagrasses represents a global threat to seagrasses and thereby an important parameter in resilience of seagrass ecosystems. In contrast seegrasses colonize and grow in hostile sediments, where they are constantly exposed to invasion of toxic gaseous sulfide. Remarkably little...... strategies of seagrasses to sustain sulfide intrusion. Using stable isotope tracing, scanning electron microscopy with x-ray analysis, tracing sulfur compounds combined with ecosystem parameters we found different spatial, intraspecific and interspecific strategies to cope with sulfidic sediments. 1...... not present in terrestrial plants at that level. Sulfide is not necessarily toxic but used as sulfur nutrition, presupposing healthy seagrass ecosystems that can support detoxification mechanisms. Presence or absence of those mechanisms determines susceptibility of seagrass ecosystems to sediment sulfide...

Gas thermodesorption study of barium and strontium cerates

International Nuclear Information System (INIS)

Aksenova, T.I.; Khromushin, I.V.; Zhotabaev, Zh.R.; Bukenov, K.D.; Medvedeva, Z.V.; Berdauletov, A.K.

2002-01-01

Kinetic of water, oxygen, hydrogen and carbon dioxide molecules release from doped and undoped samples of barium cerates and doped strontium cerates during vacuum heating was studied. The samples were prepared by inductive melting method. The following two kinds of preliminary samples treatments were used: annealing in air (650-750 deg. C) and wet nitrogen atmosphere (625 deg.C). Main results of thermodesorption studies of barium and strontium cerates are represented in the table. The samples of doped LaSrMnO were investigated also. It was found that the initial doped samples (without preliminary annealing) did not show any gas release in temperature range of 20-1100 deg. C. This fact indicates on high stability of compositions and strong bond of 'host' oxygen in their lattice. A significant amount of water and oxygen molecules were released from BaCe 0.9 Nd 0.1 O 3 samples whereas water and hydrogen molecules desorption from SrCe 0.95 Y 0.05 O 3 samples took place. Hydrogen molecules desorption was found for strontium cerates samples; no hydrogen molecules release was observed for doped and pure barium cerate samples.Intensive water molecules release from doped samples confirms the necessity of oxygen vacancies creation in these compounds to get properties of proton conductivity, since it was not found any water molecules release from annealed undoped samples of BaCeO 3 It is necessary to notice that oxygen molecules release from these samples took place at ∼1000 deg. C that is significantly higher then from BaCeNdO samples. Forms of high temperatures part of oxygen and low temperature part of water spectra indicate that phase transformations are responsible for oxygen and water molecules desorption in this cases. These results are in good agreement with literature data. Desorption of water molecules from barium and strontium cerates took place. Oxygen desorption took place only from barium cerates. It can be explained as the following: doped barium cerates have

Complete sulphate removal from neutralised acidic mine drainage with barium carbonate

CSIR Research Space (South Africa)

Swanepoel, H

2012-03-01

Full Text Available -barium-calcium) Desalination process which uses barium salts to further reduce the sulphate concentration to acceptable levels with the added advantage that sulphate removal can be controlled due to the low solubility of BaSO4. This paper reports on the results...

Barium titanate coated with magnesium titanate via fused salt method and its dielectric property

International Nuclear Information System (INIS)

Chen Renzheng; Cui Aili; Wang Xiaohui; Li Longtu

2003-01-01

Barium titanate fine particles were coated homogeneously with magnesium titanate via the fused salt method. The thickness of the magnesium titanate film is 20 nm, as verified by TEM and XRD. The mechanism of the coating is that: when magnesium chloride is liquated in 800 deg. C, magnesium will replace barium in barium titanate, and form magnesium titanate film on the surface of barium titanate particles. Ceramics sintered from the coated particles show improved high frequency ability. The dielectric constant is about 130 at the frequency from 1 to 800 MHz

30 CFR 250.504 - Hydrogen sulfide.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.504 Section 250.504... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.504 Hydrogen sulfide. When a well-completion operation is conducted in zones known to contain hydrogen sulfide (H2S) or in...

30 CFR 250.604 - Hydrogen sulfide.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.604 Section 250.604... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.604 Hydrogen sulfide. When a well-workover operation is conducted in zones known to contain hydrogen sulfide (H2S) or in...

Barium in produced water: Is it a toxicological hazard to the marine environment?

International Nuclear Information System (INIS)

Neff, J.M.

1993-01-01

Produced water is a complex aqueous mixture of organic and inorganic chemicals that often is generated in large volumes as a by-product of production of oil and gas. Produced water from offshore oil production platforms sometimes is treated to remove particulate oil and then discharged to the ocean. Barium often is the most abundant inorganic chemical, other than the dominant sea salts, in produced water. Some concern has been expressed that the large amounts of barium discharged to the ocean in produced water may have adverse effects on marine biological communities. The ecological risks associated with discharge to the ocean in produced water may have adverse effects on marine biological communities. The ecological risks associated with discharge to the ocean of barium in produced water were evaluated. Concentrations of barium in produced water from different sources range from less than 1.0 to about 2,000 mg/L, and are inversely correlated with concentrations of sulfate. Concentrations of barium in the ocean usually are in the range of 10 to 20 μg/L; the ocean is undersaturated with respect to barite (BaSO 4 ). During mixing and dilution of a produced water plume in the ocean, barium reacts with the abundant sulfate in seawater and precipitates as barite. Barite is completely nontoxic to marine organisms. Because of the high concentration of sulfate in the ocean, ionic barium can not reach concentrations high enough to be toxic to marine organisms

Carbon steel protection in G.S. (Girlder sulfide) plants. Iron sulfide scales formation conditions. Pt. 1

International Nuclear Information System (INIS)

Bruzzoni, P.; Burkart, A.L.; Garavaglia, R.N.

1981-11-01

An ASTM A 516 degree 60 carbon steel superficial protection technique submitted to a hydrogen-water sulfide corrosive medium at 2 MPa of pressure and 40-125 deg C forming on itself an iron sulfide layer was tested. Studies on pH influence, temperature, passivating mean characteristics and exposure time as well as the mechanical resistance of sulfide layers to erosion are included. (Author) [es

Qualitative analysis of barium particles coated in small intestinal mucosa of rabbit by using scanning electron microscopy

International Nuclear Information System (INIS)

Lee, Yong Suk; Ha, Hyun Kwon; Lee, Yang Seob; Kim, Jae Kyun; Yoon, Seong Eon; Kim, Jung Hoon; Chung, Dong Jin; Auh, Yong Ho

1998-01-01

To qualitatively analysed barium coating status in the intestinal mucosa, we used scanning electron microscopy to observe barium particles coated in the small intestinal mucosa of rabbit, and we attempted to assess the relationship between electron microscopic findings and radiographic densities. Six different combination of barium and methylcellulose suspensions were infused into the resected small intestines of 15 rabbits. Barium powders were mixed with water to make 40% and 70% w/v barium solutions, and also mixed with 0.5% methylcellulose solutions were used as a double contrast agent. After the infusion of barium suspensions, a mammography unit was used to obtain radiographs of the small intestine, and their optical densities were measured by a densitometer. Thereafter, photographs of barium-coated small intestinal mucosa were obtained using a scanning electron microscope (x 8,000), and the number of barium particles in the unit area were measured. To compare the relationship between the electron microscopic findings and optical densities, statistical analysis using Spearman correlation was performed. This study shows that by using scanning electron microscopy, barium particles coated on the small intestinal mucosa can be qualitatively analysed. It also shows that the number of small barium particles measured by scanning electron microscopy is related to optical densities. (author). 14 refs., 2 figs

30 CFR 250.808 - Hydrogen sulfide.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Hydrogen sulfide. 250.808 Section 250.808... OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Production Safety Systems § 250.808 Hydrogen sulfide. Production operations in zones known to contain hydrogen sulfide (H2S) or in zones where the presence of H2S...

Formation of barium strontium titanate powder by solid state reaction using different calcination temperatures

International Nuclear Information System (INIS)

Teoh Wah Tzu; Ahmad Fauzi Mohd Noor; Zainal Arifin Ahmad

2002-01-01

The unique electrical properties of large permittivity in Barium Strontium Titanate have been widely used to make capacitors; it can be produced by solid state reaction. In this study, the mixture of Barium Carbonate, Strontium Carbonate and Titanium Dioxide was calcined at 500 degree C, 1000 degree C, 1100 degree C , 1150 degree C, 1200 degree C, 1250 degree C and 1300 degree C. The results of the phases change in each stage were investigated via X ay Diffraction. The results show that the formation of Barium Strontium Titanate started at 1100 degree C with the presence of other phases. The mixture is fully reacted to form Barium Strontium Titanate at 1150 degree C. Only Barium Strontium Titanate was formed as the calcination temperature was set higher. (Author)

Influence of fuel ratios on auto combustion synthesis of barium ferrite ...

Indian Academy of Sciences (India)

Unknown

Influence of fuel ratios on auto combustion synthesis of barium ferrite nano particles. D BAHADUR*, S RAJAKUMAR and ANKIT KUMAR. Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology,. Mumbai 400 076 e-mail: dhirenb@iitb.ac.in. Abstract. Single-domain barium ferrite nano ...

Mechanochemical reduction of copper sulfide

DEFF Research Database (Denmark)

Balaz, P.; Takacs, L.; Jiang, Jianzhong

2002-01-01

The mechanochemical reduction of copper sulfide with iron was induced in a Fritsch P-6 planetary mill, using WC vial filled with argon and WC balls. Samples milled for specific intervals were analyzed by XRD and Mossbauer spectroscopy. Most of the reaction takes place during the first 10 min...... of milling and only FeS and Cu are found after 60 min. The main chemical process is accompanied by phase transformations of the sulfide phases as a result of milling. Djurleite partially transformed to chalcocite and a tetragonal copper sulfide phase before reduction. The cubic modification of FeS was formed...... first, transforming to hexagonal during the later stages of the process. The formation of off-stoichiometric phases and the release of some elemental sulfur by copper sulfide are also probable....

Strontium-90 sorption from fresh waters in the process of barium manganite modification

International Nuclear Information System (INIS)

Ryzhen'kov, A.P.; Egorov, Yu.V.

1995-01-01

Strontium-90 extraction by barium manganite from fresh water (natural non-salty water in open ponds) may be increased adding to the solution the sulfate anion containing reagents that modify a sorbent and chemically bind a sorbate. Heterogeneous anion-exchanging reaction of barium manganite transformation into barium sulfate-manganese dioxide and simultaneous coprecipitation of strontium sulfate (microelement) occur as a result of it. 9 refs., 4 figs., 1 tab

Small bowel volvulus in children. Its appearance on the barium enema examination

Energy Technology Data Exchange (ETDEWEB)

Siegel, M.J.; Shackelford, G.D.; McAlister, W.H.

1980-01-01

Two children with small bowel volvulus diagnosed on barium enema examination are reported. In one patient the volvulus was associated with malrotation and in the other patient there was a post-operative peritoneal adhesion. In both cases the diagnosis was based on beaking of the head of the barium column at the site of volvulus. Radiographic demonstration of a beak sign in the small bowel on barium enema examination should suggest a diagnosis of small bowel volvulus, and indicates the need for immediate surgery.

Modeling Sulfides, pH and Hydrogen Sulfide Gas in the Sewers of San Francisco

DEFF Research Database (Denmark)

Vollertsen, Jes; Revilla, Nohemy; Hvitved-Jacobsen, Thorkild

2015-01-01

An extensive measuring campaign targeted on sewer odor problems was undertaken in San Francisco. It was assessed whether a conceptual sewer process model could reproduce the measured concentrations of total sulfide in the wastewater and H2S gas in the sewer atmosphere, and to which degree...... such simulations have potential for further improving odor and sulfide management. The campaign covered measurement of wastewater sulfide by grab sampling and diurnal sampling, and H2S gas in the sewer atmosphere was logged. The tested model was based on the Wastewater Aerobic/Anaerobic Transformations in Sewers...... (WATS) sewer process concept, which never had been calibrated to such an extensive dataset. The study showed that the model was capable of reproducing the general levels of wastewater sulfide, wastewater pH, and sewer H2S gas. It could also reproduce the general variability of these parameters, albeit...

Sulfide Intrusion and Detoxification in the Seagrass Zostera marina

DEFF Research Database (Denmark)

Hasler-Sheetal, Harald; Holmer, Marianne

2015-01-01

Gaseous sulfide intrusion into seagrasses growing in sulfidic sediments causes little or no harm to the plant, indicating the presence of an unknown sulfide tolerance or detoxification mechanism. We assessed such mechanism in the seagrass Zostera marina in the laboratory and in the field...... as sulfate throughout the plant. We conclude that avoidance of sulfide exposure by reoxidation of sulfide in the rhizosphere or aerenchyma and tolerance of sulfide intrusion by incorporation of sulfur in the plant are likely major survival strategies of seagrasses in sulfidic sediments....

Characterization of barium titanate powder doped with sodium and potassium ions by using Rietveld refining

International Nuclear Information System (INIS)

Andrade, M.C.; Assis, J.T.; Pereira, F.R.

2009-01-01

A solid-reaction synthesis of doped barium titanate was done by employing barium carbonates, sodium, potassium and titanium oxides with classic procedures. Rietveld refining of X ray diffraction data of perovskite samples with tetragonal symmetry was applying and show good agreement. Besides, the treatment performed from 600 deg C produces nanocrystals of barium titanate with average size of 33 nm. The presence of endothermic peaks related to BaTiO 3 formation at relatively low temperatures was determined by thermal analysis. A pseudo-Voigt Thompson-Cox-Hastings function was used to fit the standard samples of barium titanate. The Rietveld method has showed be efficient to detect the influences of temperature and doping on barium titanate microstructures. (author)

How does esophagus look on barium esophagram in pediatric eosinophilic esophagitis?

Science.gov (United States)

Al-Hussaini, Abdulrahman; AboZeid, Amany; Hai, Abdul

2016-08-01

The clinical, endoscopic, and histologic findings of eosinophilic esophagitis (EoE) are well characterized; however, there have been very limited data regarding the radiologic findings of pediatric EoE. We report on the radiologic findings of pediatric EoE observed on barium esophagram and correlate them with the endoscopic findings. We identified children diagnosed with EoE in our center from 2004 to 2015. Two pediatric radiologists met after their independent evaluations of each fluoroscopic study to reach a consensus on each case. Clinical and endoscopic data were collected by retrospective chart review. Twenty-six pediatric EoE cases (age range 2-13 years; median 7.5 years) had barium esophagram done as part of the diagnostic approach for dysphagia. Thirteen children had abnormal radiologic findings of esophagus (50%): rings formation (n = 4), diffuse irregularity of mucosa (n = 8), fixed stricture formation (n = 3), and narrow-caliber esophagus (n = 10). Barium esophagram failed to show one of 10 cases of narrow-caliber esophagus and 10 of 14 cases of rings formation visualized endoscopically. The mean duration of symptoms prior to diagnosis of EoE was longer (3.7 vs. 1.7 year; p value 0.019), and the presentation with intermittent food impaction was commoner in the group with abnormal barium esophagram as compared to the group with normal barium esophagram (69% vs. 8%; p value 0.04). Barium swallow study is frequently normal in pediatric EoE. With the exception of narrow-caliber esophagus, our data show poor correlation between radiologic and endoscopic findings.

Tunable ferromagnetic resonance in La-Co substituted barium hexaferrites at millimeter wave frequencies

Science.gov (United States)

Korolev, Konstantin A.; Wu, Chuanjian; Yu, Zhong; Sun, Ke; Afsar, Mohammed N.; Harris, Vincent G.

2018-05-01

Transmittance measurements have been performed on La-Co substituted barium hexaferrites in millimeter waves. Broadband millimeter-wave measurements have been carried out using the free space quasi-optical spectrometer, equipped with a set of high power backward wave oscillators covering the frequency range of 30 - 120 GHz. Strong absorption zones have been observed in the millimeter-wave transmittance spectra of all La-Co substituted barium hexaferrites due to the ferromagnetic resonance. Linear shift of ferromagnetic resonance frequency as functions of La-Co substitutions have been found. Real and imaginary parts of dielectric permittivity of La-Co substituted barium hexaferrites have been calculated using the analysis of recorded high precision transmittance spectra. Frequency dependences of magnetic permeability of La-Co substituted barium hexaferrites, as well as saturation magnetization and anisotropy field have been determined based on Schlömann's theory for partially magnetized ferrites. La-Co substituted barium hexaferrites have been further investigated by DC magnetization to assess magnetic behavior and compare with millimeter wave data. Consistency of saturation magnetization determined independently by both millimeter wave absorption and DC magnetization have been found for all La-Co substituted barium hexaferrites. These materials seem to be quite promising as tunable millimeter wave absorbers, filters, circulators, based on the adjusting of their substitution parameters.

STUDY OF HYDROGEN SULFIDE REMOVAL FROM GROUNDWATER

Directory of Open Access Journals (Sweden)

T. Lupascu

2013-06-01

Full Text Available The process of the hydrogen sulfide removal from the underground water of the Hancesti town has been investigated. By oxygen bubbling through the water containing hydrogen sulfide, from the Hancesti well tube, sulfur is deposited in the porous structure of studied catalysts, which decreases their catalytic activity. Concomitantly, the process of adsorption / oxidation of hydrogen sulfide to sulfate take place. The kinetic research of the hydrogen sulfide removal from the Hancesti underground water, after its treatment by hydrogen peroxide, proves greater efficiency than in the case of modified carbonic adsorbents. As a result of used treatment, hydrogen sulfide is completely oxidized to sulfates

Accelerating the transit time of barium sulphate suspensions in small bowel examinations

International Nuclear Information System (INIS)

Summers, David S.; Roger, Mark D.; Allan, Paul L.; Murchison, John T.

2007-01-01

Purpose: To determine whether hyperosmolar and effervescent agents proven individually to accelerate transit time in the barium small bowel examination have an additive effect when combined, surpassing that of either agent alone. Materials and methods: One hundred and forty-nine patients were randomised to four groups. Three hundred milliliters of barium sulphate alone was given to the first group. Fifteen milliliters of iodinated hyperosmolar contrast agent (Gastrografin, meglumine/sodium diatrizoate, Schering) was given in addition to barium sulphate to the second group while six packets of effervescent granules (Carbex, Ferring) were added for the third group. The final group was given a combination of both additives and barium sulphate. The time taken following ingestion for the contrast column to reach the caecum, as assessed by frequent interval fluoroscopy, was recorded. A subgroup of 32 patients were selected randomly from the four groups, 8 from each and assessed for quality of examination. Statistical assessments were made using Kruskal-Wallis and Mann-Whitney tests. Results: One hundred and nineteen patients were analysed after exclusions. The addition of accelerant to barium sulphate, both individually and in combination significantly reduced the small bowel transit time (p < 0.001). No significant difference existed between the additives when used with barium alone. The combined group had significantly faster transit times compared to the hyperosmolar group (p = 0.02). Differences between combined and effervescent groups tended towards significance (p = 0.09). No significant difference existed between groups when examination quality was assessed. Conclusion: These results suggest that the addition of combined effervescent and hyperosmolar agents to the barium suspension may significantly shorten the small bowel transit time without adversely affecting examination quality. This has implications for patient acceptability of the examination as well as

Study of interferences in the atomic - absorption and emission of barium in nitrous oxide/acetylene flame

International Nuclear Information System (INIS)

Curtius, A.J.; Couto, M.I.

1979-01-01

The interferences of several ions that are present in oifield water and sea water in the atomic absorption and emission of barium were investigated. It was verified that the interferences of sodium, potassium, calcium, strontium and chloride are the most important. The indirect method for the determination of sulfate by measuring barium by atomic absorption after precipitating barium sulfate with an excess of barium chloride, should not be used for highly salted matrix. To avoid the interferences that are not compensated by an ionization supressor, the measurement of barium by the standard addition method or a previous sulfate separation is recommended. (Author) [pt

On film quality in barium-air double contrast colon study

International Nuclear Information System (INIS)

Rhu, Sang Hyung; Rhee, Jae Ho; Kim, Hai Sung; Cheung, Hwan

1984-01-01

The colon double contrast study provides valuable diagnostic information by means of appropriate control of Kvp and mAa when making double contrast image by injecting air into the colon after coating the colon wall by appropriately diluted Barium solution. The following experiments were performed the results of which allowed to improve the quality of film in barium-air double contrast colon study: (1) Do the pictures have uniform density when measured with a densitometer from three measuring points established in the picture by changing Kvp and mAs depending on the thickness of the patient? (2) Is the quality of the picture improved by being compensated from the adjacent area when using a wedge filter in routine check lateral decubitus and erect view? (3) What is the optimum dilution of barium solution which gives the best result for colon wall coating? The above experiments revealed that as the patient's thickness increased, it should be considered to increase mAs as well as Kvp and a wedge filter could give diagnostically very informative pictures in routine-check lateral decubitus and erect view. And 70-80% solution of Barium-water mixture provided the best quality of double contrast image

Lanthanide doped strontium-barium cesium halide scintillators

Science.gov (United States)

Bizarri, Gregory; Bourret-Courchesne, Edith; Derenzo, Stephen E.; Borade, Ramesh B.; Gundiah, Gautam; Yan, Zewu; Hanrahan, Stephen M.; Chaudhry, Anurag; Canning, Andrew

2015-06-09

The present invention provides for a composition comprising an inorganic scintillator comprising an optionally lanthanide-doped strontium-barium, optionally cesium, halide, useful for detecting nuclear material.

New efficient catalyst for ammonia synthesis: barium-promoted cobalt on carbon

DEFF Research Database (Denmark)

Hagen, Stefan; Barfod, Rasmus; Fehrmann, Rasmus

2002-01-01

Barium-promoted cobalt catalysts supported on carbon exhibit higher ammonia activities at synthesis temperatures than the commercial, multipromoted iron catalyst and also a lower ammonia......Barium-promoted cobalt catalysts supported on carbon exhibit higher ammonia activities at synthesis temperatures than the commercial, multipromoted iron catalyst and also a lower ammonia...

Barium Isotopes in Single Presolar Grains

Science.gov (United States)

Pellin, M. J.; Davis, A. M.; Savina, M. R.; Kashiv, Y.; Clayton, R. N.; Lewis, R. S.; Amari, S.

2001-01-01

Barium isotopic compositions of single presolar grains were measured by laser ablation laser resonant ionization mass spectrometry and the implications of the data for stellar processes are discussed. Additional information is contained in the original extended abstract.

Synthesis and characterization of barium ferrite–silica nanocomposites

International Nuclear Information System (INIS)

Aguilar-González, M.A.; Mendoza-Suárez, G.; Padmasree, K.P.

2013-01-01

In this work, we prepared barium ferrite-silica (BaM-SiO 2 ) nanocomposites of different molar ratios by high-energy ball milling, followed by heat-treatment at different temperatures. The microstructure, morphology and magnetic properties were characterized for different synthesis conditions by using X-ray diffraction (XRD), scanning electron microscopy (SEM) and vibrating sample magnetometry (VSM). The results indicate that 15 h of milling was enough to avoid the generation of hematite phase and to get a good dispersion of barium ferrite particles in the ceramic matrix. For milling periods beyond 15 h and heat treatment above 900 °C, the XRD patterns showed the presence of hematite phase caused by the decomposition of BaM. The agglomerate size observed through SEM analysis was around 150 nm with a good BaM dispersion into the SiO 2 matrix. The highest saturation magnetization (Ms) value obtained was 43 emu/g and the corresponding coercivity (Hc) value of 3.4 kOe for the composition 60BaM-40SiO 2 milled for 15 h and heat treated at 900 °C. This coercivity value is acceptable for the application in magnetic recording media. Highlights: • Barium ferrite–silica nanocomposites were prepared by high energy ball milling. • Optimal processing time is 15 h milling and heat treatment at 900 °C. • This is enough to avoid the generation of hematite phase. • Obtain good dispersion of barium ferrite particles in the ceramic matrix • Above this processing time shows the presence of increased amount of hematite

Controlling Barium Sulphate Scale Deposition Problems in an unbleached Kraft Paper Mill

CSIR Research Space (South Africa)

Sithole, Bruce

2015-06-01

Full Text Available Troubleshooting of scale deposits and defects in paper samples showed that the problem was caused by barium sulphate and calcium sulphate scales. However, it was ascertained that barium sulphate was more of a concern than calcium sulphate...

Development of biomonitoring equivalents for barium in urine and plasma for interpreting human biomonitoring data.

Science.gov (United States)

Poddalgoda, Devika; Macey, Kristin; Assad, Henry; Krishnan, Kannan

2017-06-01

The objectives of the present work were: (1) to assemble population-level biomonitoring data to identify the concentrations of urinary and plasma barium across the general population; and (2) to derive biomonitoring equivalents (BEs) for barium in urine and plasma in order to facilitate the interpretation of barium concentrations in the biological matrices. In population level biomonitoring studies, barium has been measured in urine in the U.S. (NHANES study), but no such data on plasma barium levels were identified. The BE values for plasma and urine were derived from U.S. EPA's reference dose (RfD) of 0.2 mg/kg bw/d, based on a lower confidence limit on the benchmark dose (BMDL 05 ) of 63 mg/kg bw/d. The plasma BE (9 μg Ba/L) was derived by regression analysis of the near-steady-state plasma concentrations associated with the administered doses in animals exposed to barium chloride dihydrate in drinking water for 2-years in a NTP study. Using a human urinary excretion fraction of 0.023, a BE for urinary barium (0.19 mg/L or 0.25 mg/g creatinine) was derived for US EPA's RfD. The median and the 95 th percentile barium urine concentrations of the general population in U.S. are below the BE determined in this study, indicating that the population exposure to inorganic barium is expected to be below the exposure guidance value of 0.2 mg/kg bw/d. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Severe acute cholangitis after endoscopic sphincterotomy induced by barium examination: A case report.

Science.gov (United States)

Zhang, Zhen-Hai; Wu, Ya-Guang; Qin, Cheng-Kun; Su, Zhong-Xue; Xu, Jian; Xian, Guo-Zhe; Wu, Shuo-Dong

2012-10-21

Endoscopic sphincterotomy (EST) is considered as a possible etiological factor for severe cholangitis. We herein report a case of severe cholangitis after endoscopic sphincterotomy induced by barium examination. An adult male patient presented with epigastric pain was diagnosed as having choledocholithiasis by ultrasonography. EST was performed and the stone was completely cleaned. Barium examination was done 3 d after EST and severe cholangitis appeared 4 h later. The patient was recovered after treated with tienam for 4 d. Barium examination may induce severe cholangitis in patients after EST, although rare, barium examination should be chosen cautiously. Cautions should be also used when EST is performed in patients younger than 50 years to avoid the damage to the sphincter of Oddi.

Reaction between barium and nitrogen in liquid sodium

International Nuclear Information System (INIS)

Addison, C.C.; Pulham, R.J.; Trevillion, E.A.

1975-01-01

Nitrogen in increasing amounts has been added to separate solutions of barium in sodium of constant composition (ca.4.40 mol % Ba) at 300 0 C. After rendering each mixture homogenous using an electromagnetic pump, filtration, and nitrogen analysis, all the N 2 added has been found in solution up to a solution composition approximating to Ba 4 N (i.e. 1.1 mol % N) beyond which the quantity of dissolved N 2 decreases progressively due to precipitation of the nitride Ba 2 N. The solubilization is interpreted in terms of strong preferential solvation of the nitride ion by barium cations. (author)

Barium atoms and N20 molecular agregates reaction

International Nuclear Information System (INIS)

Visticot, J.P.; Mestdagh, J.M.; Alcaraz, C.; Cuvellier, J.; Berlande, J.

1988-06-01

The collisions between a barium atom and N20 molecular agregates are studied, for a better understanding of the solvation part in a chemical reaction. The experiments are carried out in a crossed molecular beam device. The light coming from the collision zone is scattered, and analysed by means of a photon detector. A time-of-flight technique is applied in the investigation of the beam's polymer concentration. The results show a nearly negligible chemiluminescent effect in the reaction between barium and N20 polymer. A solvated BaO formation mechanism is proposed to justify the experimental results [fr

Regeneration of barium carbonate from barium sulphide in a pilot-scale bubbling column reactor and utilization for acid mine drainage.

Science.gov (United States)

Mulopo, J; Zvimba, J N; Swanepoel, H; Bologo, L T; Maree, J

2012-01-01

Batch regeneration of barium carbonate (BaCO(3)) from barium sulphide (BaS) slurries by passing CO(2) gas into a pilot-scale bubbling column reactor under ambient conditions was used to assess the technical feasibility of BaCO(3) recovery in the Alkali Barium Calcium (ABC) desalination process and its use for sulphate removal from high sulphate Acid Mine Drainage (AMD). The effect of key process parameters, such as BaS slurry concentration and CO(2) flow rate on the carbonation, as well as the extent of sulphate removal from AMD using the recovered BaCO(3) were investigated. It was observed that the carbonation reaction rate for BaCO(3) regeneration in a bubbling column reactor significantly increased with increase in carbon dioxide (CO(2)) flow rate whereas the BaS slurry content within the range 5-10% slurry content did not significantly affect the carbonation rate. The CO(2) flow rate also had an impact on the BaCO(3) morphology. The BaCO(3) recovered from the pilot-scale bubbling column reactor demonstrated effective sulphate removal ability during AMD treatment compared with commercial BaCO(3).

Determination of barium in natural waters by ICP-OES technique. Part II: Assessment of human exposure to barium in bottled mineral and spring waters produced in Poland.

Science.gov (United States)

Garboś, Sławomir; Swiecicka, Dorota

2013-01-01

A method of the classification of natural mineral and spring waters and maximum admissible concentration (MAC) levels of metals present in such types of waters are regulated by Commission Directive 2003/40/EC, Directive 2009/54/EC of the European Parliament and of the Council and Ordinance of Minister of Health of 30 March 2011 on the natural mineral waters, spring waters and potable waters. MAC of barium in natural mineral and spring waters was set at 1.0 mg/l, while World Health Organization determined the Ba guideline value in water intended for human consumption at the level of 0.7 mg/l. The aims of the study were: the determination of barium in natural mineral and spring waters (carbonated, non-carbonated and medium-carbonated waters) produced and bottled on the area of Poland, and assessment of human exposure to this metal presents in the above-mentioned types of waters. The study concerning barium determinations in 23 types of bottled natural mineral waters and 15 types of bottled spring waters (bought in Polish retail outlets) was conducted in 2010. The analyses were performed by validated method of determination of barium in water based on inductively coupled plasma optical emission spectrometry, using modern internal quality control scheme. Concentrations of barium determined in natural mineral and spring waters were in the ranges from 0.0136 mg/l to 1.12 mg/l and from 0.0044 mg/l to 0.43 mg/l, respectively. Only in the single case of natural mineral water the concentration of barium (1.12 mg/l), exceeded above-mentioned MAC for this metal, which is obligatory in Poland and the European Union - 1.0 mg/l. The long-term monitoring of barium concentration in another natural mineral water (2006 - 2010), in which incidental exceeding MAC was observed in 2006, was conducted. All measured barium concentrations in this water were lower than 1.0 mg/l and therefore, it is possible to state that the proper method of mixing waters taken from six independent

An experimental study on sterilized barium sulfate (BaSO4) for vertebroplasty

International Nuclear Information System (INIS)

Chen Long; Ni Caifang; Ding Yi; Wang Yijin

2005-01-01

Objective: To search the proper sterilization method of barium for vertebroplasty. Methods: Perfusion agents were classified into two groups with ratio of powder/liquid(g/ml) as 3:2, and the percentage of BsSO 4 in powder was 20%. The barium powder in one group was sterilized by dry-heat and by ethylene oxide in the other. The barium powder of each group was germicultured and the polymerization time, CT value, strength and stiffness were measured respectively including 6 samples. Two independent-samples t text was used for analysis. Results: The germiculture in each group was negative. The difference in polmerization time and CT value of each group were not significant (P>0.05), while the strength and stiffness were significantly different (P<0.05). Conclusions: Sterilized effects of two groups were satisfied but the dry-heat barium sulfate is superior, more suitable for vertebroplasty. (authors)

Electron transfer to sulfides:

International Nuclear Information System (INIS)

Meneses, Ana Belen; Antonello, Sabrina; Arevalo, Maria Carmen; Maran, Flavio

2005-01-01

The problem of characterizing the steps associated with the dissociative reduction of sulfides has been addressed. The electrochemical reduction of diphenylmethyl para-methoxyphenyl sulfide in N,N-dimethylformamide, on both glassy carbon and mercury electrodes, was chosen as a test system. The electrode process involves the slow heterogeneous outer-sphere electron transfer to the sulfide, the fast cleavage of the C-S bond, the reduction of the ensuing carbon radical, and the self-protonation triggered by the generation of the strong base Ph 2 CH - . The latter reaction is rather slow, in agreement with the large intrinsic barriers characterizing proton transfers between CH-acids and carbon bases. The dissociative reduction was studied in the presence of an exogenous acid. The results, obtained by convolution analysis, point to a stepwise DET mechanism in which the ET step is accompanied by rather large reorganization energy. Similar results were obtained on both electrode materials. Analysis of the heterogeneous electron transfer and associated C-S bond cleavage indicate that the reduction of this and other sulfides lies between the stepwise dissociative electron transfers leading to the formation of stiff π* radical anions and those going through the intermediacy of loose σ* radical anions

Interactions between nitrogen molecules and barium atoms on Ru (0001) surface

International Nuclear Information System (INIS)

Zhao Xinxin; Mi Yiming; Xu Hongxia; Wang Lili; Ren Li; Tao Xiangming; Tan Mingqiu

2011-01-01

We had performed first principles calculations on interactions between nitrogen molecules and barium atoms on Ru (0001) surface using density function theory methods. It was shown that effects of barium atoms weakened the bond strength of nitrogen molecules. The bond length of nitrogen molecule increases from 0.113 nm on Ru (001)-N 2 to 0.120 nm on Ru (001)-N 2 /Ba surface. While stretch vibrational frequency of nitrogen molecule decreased from 2222 cm -1 and charge transfer toward nitrogen molecule increased from 0.3 e to 1.1 e. Charge was mainly translated from 6 s orbitals of barium atoms to 4 d orbitals of substrate, which enhanced the hybridization between 4 d and 2 π orbitals and increased the dipole moment of 5 σ and d π orbitals of nitrogen molecule. The molecular dipole moment of nitrogen molecule was increased by -0.136 e Anstrom. It was suggested that barium had some characters to be an electronic promoter on the process of activating nitrogen molecules on Ru (0001) surface. (authors)

Hydrogen sulfide can inhibit and enhance oxygenic photosynthesis in a cyanobacterium from sulfidic springs

NARCIS (Netherlands)

Klatt, Judith M.; Haas, Sebastian; Yilmaz, Pelin; de Beer, Dirk; Polerecky, Lubos

We used microsensors to investigate the combinatory effect of hydrogen sulfide (H2S) and light on oxygenic photosynthesis in biofilms formed by a cyanobacterium from sulfidic springs. We found that photosynthesis was both positively and negatively affected by H2S: (i) H2S accelerated the recovery of

Barium inhibits arsenic-mediated apoptotic cell death in human squamous cell carcinoma cells.

Science.gov (United States)

Yajima, Ichiro; Uemura, Noriyuki; Nizam, Saika; Khalequzzaman, Md; Thang, Nguyen D; Kumasaka, Mayuko Y; Akhand, Anwarul A; Shekhar, Hossain U; Nakajima, Tamie; Kato, Masashi

2012-06-01

Our fieldwork showed more than 1 μM (145.1 μg/L) barium in about 3 μM (210.7 μg/L) arsenic-polluted drinking well water (n = 72) in cancer-prone areas in Bangladesh, while the mean concentrations of nine other elements in the water were less than 3 μg/L. The types of cancer include squamous cell carcinomas (SCC). We hypothesized that barium modulates arsenic-mediated biological effects, and we examined the effect of barium (1 μM) on arsenic (3 μM)-mediated apoptotic cell death of human HSC-5 and A431 SCC cells in vitro. Arsenic promoted SCC apoptosis with increased reactive oxygen species (ROS) production and JNK1/2 and caspase-3 activation (apoptotic pathway). In contrast, arsenic also inhibited SCC apoptosis with increased NF-κB activity and X-linked inhibitor of apoptosis protein (XIAP) expression level and decreased JNK activity (antiapoptotic pathway). These results suggest that arsenic bidirectionally promotes apoptotic and antiapoptotic pathways in SCC cells. Interestingly, barium in the presence of arsenic increased NF-κB activity and XIAP expression and decreased JNK activity without affecting ROS production, resulting in the inhibition of the arsenic-mediated apoptotic pathway. Since the anticancer effect of arsenic is mainly dependent on cancer apoptosis, barium-mediated inhibition of arsenic-induced apoptosis may promote progression of SCC in patients in Bangladesh who keep drinking barium and arsenic-polluted water after the development of cancer. Thus, we newly showed that barium in the presence of arsenic might inhibit arsenic-mediated cancer apoptosis with the modulation of the balance between arsenic-mediated promotive and suppressive apoptotic pathways.

M series resonant x-ray lines of barium for near threshold electron excitation

International Nuclear Information System (INIS)

Morgon, D.V.

1992-01-01

An investigation of the M series resonant x-ray emission lines of barium for near threshold electron excitation was undertaken with a vacuum double crystal spectrometer equipped with potassium acid phthalate crystals. X-ray continuum isochromats were obtained for barium samples using the double crystal spectrometer as a monochrometer set to pass 532 eV photons. The rotatable anode allowed the samples to be observed by either the double crystal spectrometer or a soft x-ray appearance potential spectrometer, which was used for monitoring the surface of the varium sample for contamination, and to provide a cross-check for the double crystal spectrometer data. Barium M series characteristic x-ray spectra for 2.0 keV electron excitation were obtained for a variety of samples, and it was discovered that the fluorescent and resonant x-ray emission line energies remained virtually the same, regardless of the chemical condition of the sample. The continuum resonance effect was observed for near-threshold energy electron excitation, but it was significantly weaker than the same effect observed previously for lanthanum or cerium. The electron excitation energy and intensity of this effect were strongly dependent on the chemical condition of the barium sample. X-ray continuum isochromats were observed for pure and contaminated barium samples at a photon energy of 532 eV. For pure metallic barium, a peak associated with 4f electronic states was observed at an energy of about 10.2 eV above the Fermi level. When the sample was exposed to 1.5 x 10 4 Langmuir of air, the 4f structure became more sharply peaked, and shifted to an energy of about 12.0 eV above the Fermi level. A continuum isochromat of barium oxide was also observed. Chemical shifts in barium M IV and M V appearance potential spectra are therefore caused soley by shifts in the energy position of the empty 4f electronic states relative to the Fermi level

Modified small bowel follow-through using methylcellulose after administration of barium suspension : comparison with conventional series

International Nuclear Information System (INIS)

Shin, Ji Hoon; Ha, Hyun Kwon; Park, Sung Tae; Yoon, Soo Woong; Kim, Ho Sung; Kim, Sun Mi

1998-01-01

To compare modified small bowel follow-through (SBFT) using methylcellulose after the administration of barium suspension with a conventional series. Materials and Methods : In order to evaluate small bowel pathology, modified SBFT was performed in 155 patients during a 15 month period. All patients received 600 mL of methylcellulose ; 98 had taken 250 mL of 40% wt/vol barium suspension and 57 had taken 150 mL of 70% barium. For the group of 98, the barium suspension was prepared by mixing barium powder with water (n=46) or with methylcellulose in(n=52). For comparison with a modified series, 49 patients who underwent conventional SBFT using 500 mL of 40 %wt/vol barium were lso included. Image quality was rated by three radiologists as p oor , f air , g ood , or e xcellent . We analyzed the relationship between image quality, transit time and small bowel pathology;the sensitivity and specificity of each technique was also determined. Results : Among the four techniques, modified SBFT with 250 mL of 40% wt/vol barium suspension, prepared by mixing barium powder with methylcellulose, showed the best image quality ['excellent' result in 33 of the 52 patients (63%)] and shortest transit time to the cecum. The high image quality of this technique was not affected by the presence of small bowel pathology;its use resulted in the lowest incidence and slowest development of flocculation. The sensitivity (91-95%) of the three modified SBFT procedures was superior to that of a conventional series(76%), but there was no difference in specificity.Conclusion : Modified SBFT using methylcellulose after administering barium suspension with barium powder as a mixing agent is a simple technique. Its use easily improves the image quality and diagnostic accuracy of peroral SBFT

Radiologic diagnosis of gastro-oesophageal reflux. Comparison of barium and low-density contrast medium

Energy Technology Data Exchange (ETDEWEB)

Fransson, S.G.; Soekjer, H.; Johansson, K.E.; Tibbling, L.

It has been proposed that the high density of ordinary barium suspension may complicate the radiologic diagnosis of gastro-oesophageal reflux. For this reason P-contrast was developed (Ferring AB); a contrast medium with the same density as water (1 g/cm/sup 3/). A comparison of P-contrast and barium (Mixobar Ventrikel 400 mg/ml) was performed in 82 patients. All patients were examined with both contrast media and the findings were compared with those at reflux test at manometry, endoscopy and 24-hour pH monitoring. Another 40 patients and 15 symptom-free controls were examined with two different amounts of barium, 100 ml and 200 ml, to study if the radiologic diagnosis of reflux varied with the volume of contrast medium administered. P-contrast was found to have no advantages over barium for the diagnosis of gastro-oesophageal reflux. The outcome of the radiologic examination was not influenced by the different volumes of barium used.

Anion and cation diffusion in barium titanate and strontium titanate; Anionen- und Kationendiffusion in Barium- und Strontiumtitanat

Energy Technology Data Exchange (ETDEWEB)

Kessel, Markus Franz

2012-12-19

Perovskite oxides show various interesting properties providing several technical applications. In many cases the defect chemistry is the key to understand and influence the material's properties. In this work the defect chemistry of barium titanate and strontium titanate is analysed by anion and cation diffusion experiments and subsequent time-of-flight secondary ion mass spectrometry (ToF-SIMS). The reoxidation equation for barium titanate used in multi-layer ceramic capacitors (MLCCs) is found out by a combination of different isotope exchange experiments and the analysis of the resulting tracer diffusion profiles. It is shown that the incorporation of oxygen from water vapour is faster by orders of magnitude than from molecular oxygen. Chemical analysis shows the samples contain various dopants leading to a complex defect chemistry. Dysprosium is the most important dopant, acting partially as a donor and partially as an acceptor in this effectively acceptor-doped material. TEM and EELS analysis show the inhomogeneous distribution of Dy in a core-shell microstructure. The oxygen partial pressure and temperature dependence of the oxygen tracer diffusion coefficients is analysed and explained by the complex defect chemistry of Dy-doped barium titanate. Additional fast diffusion profiles are attributed to fast diffusion along grain boundaries. In addition to the barium titanate ceramics from an important technical application, oxygen diffusion in cubic, nominally undoped BaTiO{sub 3} single crystals has been studied by means of {sup 18}O{sub 2}/{sup 16}O{sub 2} isotope exchange annealing and subsequent determination of the isotope profiles in the solid by ToF-SIMS. It is shown that a correct description of the diffusion profiles requires the analysis of the diffusion through the surface space-charge into the material's bulk. Surface exchange coefficients, space-charge potentials and bulk diffusion coefficients are analysed as a function of oxygen partial

Impurities in barium titanate posistor ceramics

Czech Academy of Sciences Publication Activity Database

Korniyenko, S. M.; Bykov, I. P.; Glinchuk, M. J.; Laguta, V. V.; Belous, A. G.; Jastrabík, Lubomír

2000-01-01

Roč. 239, - (2000), s. 1209-1218 ISSN 0015-0193 Institutional research plan: CEZ:AV0Z1010914 Keywords : barium titanate phase transition * ESR * positive temperature coefficient of resistivity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.547, year: 2000

Technetium behavior in sulfide and ferrous iron solutions

International Nuclear Information System (INIS)

Lee, S.Y.; Bondietti, E.A.

1982-01-01

Pertechnetate oxyanion ( 99 TcO 4- ), a potentially mobile species in leachate from a breached radioactive waste repository, was removed from a brine solution by precipitation with sulfide, iron, and ferrous sulfide at environmental pH's. Maghemite (ν-Fe 2 O 3 ) and geothite (α-FeOOH) were the dominant minerals in the precipitate obtained from the TcO 4- -ferrous iron reaction. The observation of small particle size and poor crystallinity of the minerals formed in the presence of Tc suggested that the Tc was incorporated into the mineral structure after reduction to a lower valence state. Amorphous ferrous sulfide, an initial phase precipitating in the TcO 4- -ferrous iron-sulfide reaction, was transformed to goethite and hematite (α-Fe 2 O 3 ) on aging. The black precipitate obtained from the TcO 4- -sulfide reaction was poorly crystallized technetium sulfide (Tc 2 S 7 ) which was insoluble in both acid and alkaline solution in the absence of strong oxidents. The results suggested that ferrous- and/or sulfide-bearing groundwaters and minerals in host rocks or backfill barriers could reduce the mobility of Tc through the formation of less-soluble Tc-bearing iron and/or sulfide minerals

Gastroesophageal reflux: comparison of barium studies with 24-h pH monitoring

International Nuclear Information System (INIS)

Pan, John J.; Levine, Marc S.; Redfern, Regina O.; Rubesin, Stephen E.; Laufer, Igor; Katzka, David A.

2003-01-01

Objective: To determine the correlation between massive gastroesophageal reflux (GER) on barium studies and pathologic acid reflux on 24-h pH monitoring. Methods: A search of hospital records from January 1997 to January 2001 revealed 28 patients who underwent both barium studies and 24-h pH monitoring. The radiologic reports were reviewed to determine the presence and degree of GER. Patients with reflux to or above the thoracic inlet either spontaneously or with provocative maneuvers in the recumbent position were classified as having massive reflux, whereas the remaining patients with reflux below the thoracic inlet or no reflux comprised the control group. The pH monitoring reports were also reviewed to determine if pathologic acid reflux was present in the recumbent position. The findings on these studies were then compared to determine the frequency of pathologic acid reflux in the recumbent position on pH monitoring in patients with massive reflux on barium studies compared with the control group. Results: Massive GER was observed on barium studies in 11 (39%) of the 28 patients and reflux below the thoracic inlet or no reflux in the remaining 17 patients (61%) who comprised the control group. All 11 patients (100%) with massive reflux on barium studies had pathologic acid reflux on pH monitoring in the recumbent position compared with six (35%) of 17 patients in the control group (P=0.0009). The pH in the distal esophagus on pH monitoring was less than 4.0 for 13.1% of the recumbent period for patients with massive GER on barium studies compared with 6.2% of the recumbent period for the control group (P=0.0076). Conclusion: Although 24-h pH monitoring remains the gold standard for the detection of GER, our experience suggests that patients with massive reflux on barium studies are so likely to have pathologic acid reflux in the recumbent position that these individuals can be further evaluated and treated for their gastroesophageal reflux disease (GERD

Gastroesophageal reflux: comparison of barium studies with 24-h pH monitoring

Energy Technology Data Exchange (ETDEWEB)

Pan, John J.; Levine, Marc S. E-mail: levine@oasis.rad.upenn.edu; Redfern, Regina O.; Rubesin, Stephen E.; Laufer, Igor; Katzka, David A

2003-08-01

Objective: To determine the correlation between massive gastroesophageal reflux (GER) on barium studies and pathologic acid reflux on 24-h pH monitoring. Methods: A search of hospital records from January 1997 to January 2001 revealed 28 patients who underwent both barium studies and 24-h pH monitoring. The radiologic reports were reviewed to determine the presence and degree of GER. Patients with reflux to or above the thoracic inlet either spontaneously or with provocative maneuvers in the recumbent position were classified as having massive reflux, whereas the remaining patients with reflux below the thoracic inlet or no reflux comprised the control group. The pH monitoring reports were also reviewed to determine if pathologic acid reflux was present in the recumbent position. The findings on these studies were then compared to determine the frequency of pathologic acid reflux in the recumbent position on pH monitoring in patients with massive reflux on barium studies compared with the control group. Results: Massive GER was observed on barium studies in 11 (39%) of the 28 patients and reflux below the thoracic inlet or no reflux in the remaining 17 patients (61%) who comprised the control group. All 11 patients (100%) with massive reflux on barium studies had pathologic acid reflux on pH monitoring in the recumbent position compared with six (35%) of 17 patients in the control group (P=0.0009). The pH in the distal esophagus on pH monitoring was less than 4.0 for 13.1% of the recumbent period for patients with massive GER on barium studies compared with 6.2% of the recumbent period for the control group (P=0.0076). Conclusion: Although 24-h pH monitoring remains the gold standard for the detection of GER, our experience suggests that patients with massive reflux on barium studies are so likely to have pathologic acid reflux in the recumbent position that these individuals can be further evaluated and treated for their gastroesophageal reflux disease (GERD

Barium and manganese-doped zinc silicate rods prepared by mesoporous template route and their luminescence property

Science.gov (United States)

Dang, Lingyan; Tian, Chen; Zhao, Shifeng; Lu, Qingshan

2018-06-01

Barium and manganese-doped zinc silicates was prepared under hydrothermal treatment by mesoporous template route employing mesoporous silica as an active template. The sample displays a rod-like morphology with a mean diameter of ∼40 nm and a mean length of ∼450 nm, which inherits the characteristics of mesoporous silica. The individual rods show single crystalline and assemble into bundle-like hierarchical structure along the channels of the mesoporous silica. When barium ions together with manganese ions are co-doped in zinc silicate, the green emission corresponding to manganese ions display a significant enhancement, especially for the sample with the barium doping concentration of 0.08, which indicates that an energy transfer from barium to manganese ions takes place. With further increasing barium concentration from 0.08 to 0.10, the recombination between the defects related to barium and the excitation states of the manganese dominates accompanying non-radiative transitions which can reduce the emission efficiency.

Electronic and chemical properties of barium and indium clusters

International Nuclear Information System (INIS)

Onwuagba, B.N.

1992-11-01

The ground state electronic and chemical properties of divalent barium and trivalent indium are investigated in a self-consistent manner using the spin-polarized local density approximation in the framework of Density Functional Theory. A jellium model is adopted in the spirit of Gunnarsson and Lundqvist exchange and correlation energies and the calculated properties primarily associated with the s-p orbitals in barium and p orbitals in indium provide deepened insight towards the understanding of the mechanisms to the magic numbers in both clusters. (author). 21 refs, 5 figs

Preparation and characterization of antimony barium composite oxide photocatalysts

Science.gov (United States)

Han, X. P.; Yao, B. H.; Pan, Q. H.; Pen, C.; Zhang, C. L.

2018-01-01

In this paper, two kinds of antimony barium composite oxide photocatalysts have been prepared by two methods and characterized by XRD and SEM. The photocatalytic activity was evaluated by a photocatalytic reactor and an ultraviolet spectrophotometer. The results showed that-BaSb2O5•4H2O, BaSb2O6 two kinds of antimony barium composite oxide photocatalysts were successfully prepared in this experiment and they showed good photocatalytic properties. In addition, BaSb2O6 morphology showed more regular, microstructure and better catalytic performance.

Carbon steel protection in G.S. (Girlder sulfide) plants. Pressure influence on iron sulfide scales formation. Pt. 5

International Nuclear Information System (INIS)

Delfino, C.A.; Lires, O.A.; Rojo, E.A.

1987-01-01

In order to protect carbon steel towers and piping of Girlder sulfide (G.S.) experimental heavy water plants against corrosion produced by the action of aqueous solutions of hydrogen sulfide, a method, previously published, was developed. Carbon steel, exposed to saturated aqueous solutions of hydrogen sulfide, forms iron sulfide scales. In oxygen free solutions evolution of corrosion follows the sequence: mackinawite → cubic ferrous sulfide → troilite → pyrrotite → pyrite. Scales formed by pyrrotite-pyrite or pyrite are the most protective layers (these are obtained at 130 deg C, 2MPa, for periods of 14 days). Experiments, at 125 deg C and periods of 10-25 days, were performed in two different ways: 1- constant pressure operations at 0.5 and 1.1 MPa. 2- variable pressure operation between 0.3-1 MPa. In all cases pyrrotite-pyrite scales were obtained. (Author) [es

Preparation and properties of yttria doped tetragonal zirconia polycrystal/Sr-doped barium hexaferrite ceramic composites

International Nuclear Information System (INIS)

Wang, Shanshan; Zhang, Chao; Guo, Ruisong; Liu, Lan; Yang, Yuexia; Li, Kehang

2015-01-01

Highlights: • The 3Y-TZP/Sr-doped barium ferrite composites were prepared. • The saturation magnetization was improved by 15% with Sr-doping. • The dispersion coefficient p could reflect the microscopic lattice variation. • The composite with x = 0.5 had the maximum fracture toughness of 8.3 MPa m 1/2 . - Abstract: The effects of substitution of Ba 2+ by Sr 2+ on the magnetic property of barium ferrite and addition barium ferrite secondary phase to the 3 mol% yttria-doped tetragonal zirconia polycrystal (3Y-TZP) matrix on the mechanical property of composites were investigated. The Sr-doped barium ferrite (Ba 1−x Sr x Fe 12 O 19 , x = 0, 0.25, 0.50 and 0.75) was synthesized by solid-state reaction in advance. Then 3Y-TZP/20 wt% Sr-doped barium ferrite composites were prepared by means of conventional ceramic method. It was found that a moderate amount of Sr added to barium ferrite could boost the saturation magnetization by 15% compared with the composites without Sr-doping. Besides, the composite with x = 0.50 possessed the best mechanical properties, such as 11.5 GPa for Vickers hardness and 8.3 MPa m 1/2 for fracture toughness, respectively. It was demonstrated that magnetic and mechanical properties of the composites could be harmonized by the incorporation of barium ferrite secondary phase

Measurements of barium photocathode quantum yields at four excimer laser wavelengths

International Nuclear Information System (INIS)

Van Loy, M.D.; Young, A.T.; Leung, K.N.

1992-06-01

The electron quantum yields from barium cathodes excited by excimer laser radiation at 193, 248, 308, and 351 nm have been determined. Experiments with different cathode surface preparation techniques reveal that deposition of barium film a few microns thick on a clean copper surface under moderate vacuum conditions achieves relatively high quantum efficiencies. Quantum yields measured from surfaces prepared in this manner are 2.3 x 10 -3 at 193 nm, 7.6 x 10 - 4 at 248 nm, 6.1 x 10 -4 at 308 nm, and 4.0 x 10 -4 at 351 nm. Other preparation techniques, such as laser cleaning of a solid barium surface, produced quantum yields that were at least an order of magnitude lower than these values

Obtaining of a barium compound by combustion chemistry and their evaluation as Co adsorbent

International Nuclear Information System (INIS)

Rosas G, N.

2008-01-01

In this work, barium carbonate synthesized by chemical combustion method using a chemical precursor prepared by the combination of barium nitrate and urea as a fuel, with a 1:1 molar ratio in aqueous solution, the chemical precursor was heated to evaporate excess water, producing a homogeneous viscous liquid, that when heated to 900 centi grades for 5 minutes an exothermic reaction was produced very quickly and abruptly, forming a white powder final product, fine porous, little spongy, dry and crystalline ready to be used as material adsorbent. Additionally, the effect of water on the synthesis by chemical combustion was studied. Simultaneously, and with the purpose of comparing the advantages and disadvantages of the method by chemical combustion, barium carbonate was synthesized by precipitation method using barium nitrate salts and sodium carbonate. Synthesized barium carbonate, was characterized by X-ray diffraction, thermal gravimetric analysis, infrared spectrometry and scanning electron microscopy. We studied the adsorption capacity of Co present in aqueous solution by static tests on materials synthesized at room temperature using the neutron activation analysis. It was found that the synthesis by chemical combustion provides an interesting alternative compared to the synthesis by precipitation because it offers simplicity of synthesis and speed to have a good adsorbent material. It was found that the barium carbonate synthesized by the chemical combustion method using in their synthesis 1.0 ml of water, was the one who achieved the maximum adsorption capacity of 95.6% compared with the barium carbonate prepared by precipitation, which reached a capacity adsorption of 51.48%. (Author)

Experimental simulations of sulfide formation in the solar nebula.

Science.gov (United States)

Lauretta, D S; Lodders, K; Fegley, B

1997-07-18

Sulfurization of meteoritic metal in H2S-H2 gas produced three different sulfides: monosulfide solid solution [(Fe,Ni)1-xS], pentlandite [(Fe,Ni)9-xS8], and a phosphorus-rich sulfide. The composition of the remnant metal was unchanged. These results are contrary to theoretical predictions that sulfide formation in the solar nebula produced troilite (FeS) and enriched the remaining metal in nickel. The experimental sulfides are chemically and morphologically similar to sulfide grains in the matrix of the Alais (class CI) carbonaceous chondrite, suggesting that these meteoritic sulfides may be condensates from the solar nebula.

Photometric Calibration of the Barium Cloud Image in a Space Active Experiment: Determining the Release Efficiency

International Nuclear Information System (INIS)

Xie Liang-Hai; Li Lei; Wang Jing-Dong; Tao Ran; Cheng Bing-Jun; Zhang Yi-Teng

2014-01-01

The barium release experiment is an effective method to explore the near-earth environment and to study all kinds of space physics processes. The first space barium release experiment in China was successfully carried out by a sounding rocket on April 5, 2013. This work is devoted to calculating the release efficiency of the barium release by analyzing the optical image observed during the experiment. First, we present a method to calibrate the images grey value of barium cloud with the reference stars to obtain the radiant fluxes at different moments. Then the release efficiency is obtained by a curve fitting with the theoretical evolution model of barium cloud. The calculated result is basically consistent with the test value on ground

CT-Guided Percutaneous Transthoracic Localization of Pulmonary Nodules Prior to Video-Assisted Thoracoscopic Surgery Using Barium Suspension

Energy Technology Data Exchange (ETDEWEB)

Lee, Nyoung Keun; Park, Chang Min; Kang, Chang Hyun; Jeon, Yoon Kyung; Choo, Ji Yung; Lee, Hyun Ju; Goo, Jin Mo [Seoul National University College of Medicine, Seoul (Korea, Republic of)

2012-11-15

To describe our initial experience with CT-guided percutaneous barium marking for the localization of small pulmonary nodules prior to video-assisted thoracoscopic surgery (VATS). From October 2010 to April 2011, 10 consecutive patients (4 men and 6 women; mean age, 60 years) underwent CT-guided percutaneous barium marking for the localization of 10 small pulmonary nodules (mean size, 7.6 mm; range, 3-14 mm): 6 pure ground-glass nodules, 3 part-solid nodules, and 1 solid nodule. A 140% barium sulfate suspension (mean amount, 0.2 mL; range, 0.15-0.25 mL) was injected around the nodules with a 21-gauge needle. The technical details, surgical findings and pathologic features associated with barium localizations were evaluated. All nodules were marked within 3 mm (mean distance, 1.1 mm; range, 0-3 mm) from the barium ball (mean diameter, 9.6 mm; range, 8-16 mm) formed by the injected barium suspension. Pneumothorax occurred in two cases, for which one needed aspiration. However, there were no other complications. All barium balls were palpable during VATS and visible on intraoperative fluoroscopy, and were completely resected. Both the whitish barium balls and target nodules were identifiable in the frozen specimens. Pathology revealed one invasive adenocarcinoma, five adenocarcinoma-in-situ, two atypical adenomatous hyperplasias, and two benign lesions. In all cases, there were acute inflammations around the barium balls which did not hamper the histological diagnosis of the nodules. CT-guided percutaneous barium marking can be an effective, convenient and safe pre-operative localization procedure prior to VATS, enabling accurate resection and diagnosis of small or faint pulmonary nodules.

CT-Guided Percutaneous Transthoracic Localization of Pulmonary Nodules Prior to Video-Assisted Thoracoscopic Surgery Using Barium Suspension

International Nuclear Information System (INIS)

Lee, Nyoung Keun; Park, Chang Min; Kang, Chang Hyun; Jeon, Yoon Kyung; Choo, Ji Yung; Lee, Hyun Ju; Goo, Jin Mo

2012-01-01

To describe our initial experience with CT-guided percutaneous barium marking for the localization of small pulmonary nodules prior to video-assisted thoracoscopic surgery (VATS). From October 2010 to April 2011, 10 consecutive patients (4 men and 6 women; mean age, 60 years) underwent CT-guided percutaneous barium marking for the localization of 10 small pulmonary nodules (mean size, 7.6 mm; range, 3-14 mm): 6 pure ground-glass nodules, 3 part-solid nodules, and 1 solid nodule. A 140% barium sulfate suspension (mean amount, 0.2 mL; range, 0.15-0.25 mL) was injected around the nodules with a 21-gauge needle. The technical details, surgical findings and pathologic features associated with barium localizations were evaluated. All nodules were marked within 3 mm (mean distance, 1.1 mm; range, 0-3 mm) from the barium ball (mean diameter, 9.6 mm; range, 8-16 mm) formed by the injected barium suspension. Pneumothorax occurred in two cases, for which one needed aspiration. However, there were no other complications. All barium balls were palpable during VATS and visible on intraoperative fluoroscopy, and were completely resected. Both the whitish barium balls and target nodules were identifiable in the frozen specimens. Pathology revealed one invasive adenocarcinoma, five adenocarcinoma-in-situ, two atypical adenomatous hyperplasias, and two benign lesions. In all cases, there were acute inflammations around the barium balls which did not hamper the histological diagnosis of the nodules. CT-guided percutaneous barium marking can be an effective, convenient and safe pre-operative localization procedure prior to VATS, enabling accurate resection and diagnosis of small or faint pulmonary nodules.

Inconceivable Hypokalemia: A Case Report of Acute Severe Barium Chloride Poisoning

Directory of Open Access Journals (Sweden)

Haibo Tao

2016-01-01

Full Text Available Barium is a heavy divalent alkaline earth metal that has been known as a muscle poison. Barium can cause human toxicity, which may lead to significant hypokalemia and have serious consequences. This paper reports a case of unprecedented barium intoxication in which the patient, who suffered from depression, swallowed at least 3.0 g barium chloride to commit suicide. On admission, the patient presented with nausea, vomiting, stomach burning feeling, dizziness, and weakness. Emergency biochemical testing showed that the patient was suffering from severe hypokalemia (K+ 1.7 mmol/L. His electrocardiogram (ECG prompted atrioventricular blocking, ventricular tachycardia, prolongation of PR interval, ST segment depression with U waves, and T wave inversion. Intravenous potassium supplements were given immediately to correct hypokalemia and regular monitoring of vital signs and fluid balance was arranged. After all-out rescue of our hospital personnel, the condition of the patient is currently stable and he is gradually recovering. This case exemplifies the weaknesses of the management of toxic substances and the lack of mental health education for young people. We hope to get more attention for the supervision of toxic substances and the healthy development of young people.

Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE.

Science.gov (United States)

Anderson, N G; Butler, A P; Scott, N J A; Cook, N J; Butzer, J S; Schleich, N; Firsching, M; Grasset, R; de Ruiter, N; Campbell, M; Butler, P H

2010-09-01

Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 microA). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications.

Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

Energy Technology Data Exchange (ETDEWEB)

Anderson, N.G. [University of Otago, Department of Radiology, Christchurch (New Zealand); Butler, A.P. [University of Otago, Department of Radiology, Christchurch (New Zealand); University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Scott, N.J.A. [University of Otago, Department of Medicine, Christchurch (New Zealand); Cook, N.J. [Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Butzer, J.S. [Karlsruhe Institute of Technology, Physics Department, Karlsruhe (Germany); Schleich, N. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand); Christchurch Hospital, Medical Physics and Bioengineering, Christchurch (New Zealand); Firsching, M. [Friedrich Alexander University, Physics Department, Erlangen (Germany); Grasset, R.; Ruiter, N. de [University of Canterbury, Hitlab NZ, Christchurch (New Zealand); Campbell, M. [European Organisation for Nuclear Research, Physics Section, Geneva (Switzerland); Butler, P.H. [University of Canterbury, Physics and Astronomy, Christchurch (New Zealand)

2010-09-15

Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 {mu}A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct from soft tissue and bone in all six mice. Calcium, iodine and barium were displayed as separate channels on 3D colour images at <55 {mu}m isotropic voxels. Spectral CT distinguishes contrast agents with K-edges only 4 keV apart. Multi-contrast imaging and molecular CT are potential future applications. (orig.)

Sulfide response analysis for sulfide control using a pS electrode in sulfate reducing bioreactors

NARCIS (Netherlands)

Villa Gomez, D.K.; Cassidy, J.; Keesman, K.J.; Sampaio, R.M.; Lens, P.N.L.

2014-01-01

Step changes in the organic loading rate (OLR) through variations in the influent chemical oxygen demand (CODin) concentration or in the hydraulic retention time (HRT) at constant COD/SO4 2- ratio (0.67) were applied to create sulfide responses for the design of a sulfide control in sulfate reducing

A Comparative Study on Magnetostructural Properties of Barium Hexaferrite Powders Prepared by Polyethylene Glycol

OpenAIRE

Zehra Durmus

2014-01-01

Nanocrystalline particles of barium hexaferrite were synthesized by a sol-gel combustion route using nitrate-citrate gels prepared from metal nitrates and citric acid solutions with Fe/Ba molar ratio 12. The present paper aims to study the effect of addition of polyethylene glycol (PEG) solutions with different molecular weights (MW: 400, 2000, and 10.000 g/mol) on magnetostructural properties of barium hexaferrite. The formation of the barium hexaferrite was inspected using X-ray diffractio...

Adsorption of sulfide ions on cerussite surfaces and implications for flotation

International Nuclear Information System (INIS)

Feng, Qicheng; Wen, Shuming; Zhao, Wenjuan; Deng, Jiushuai; Xian, Yongjun

2016-01-01

Highlights: • A new discussion on the lead sulfide species is introduced. • The Na_2S concentration determines cerussite sulfidization. • The activity of lead sulfide species also determines cerussite sulfidization. • Disulfide and polysulfide in lead sulfide species affect its activity. - Abstract: The adsorption of sulfide ions on cerussite surfaces and implications for flotation were studied by X-ray photoelectron spectroscopy (XPS) analysis, micro-flotation tests, and surface adsorption experiments. The XPS analysis results indicated that lead sulfide species formed on the mineral surface after treatment by Na_2S, and the increase in the Na_2S concentration was beneficial for sulfidization. In addition to the content of lead sulfide species, its activity, which was determined by the proportion of sulfide, disulfide and polysulfide, also played an important role in cerussite sulfidization. Micro-flotation tests results demonstrated that insufficient or excessive addition of Na_2S in pulp solutions has detrimental effects on flotation performance, which was attributed to the dosage of Na_2S and the activity of lead sulfide species formed on the mineral surface. Surface adsorption experiments of sulfide ions determined the residual S concentrations in pulp solutions and provided a quantitative illustration for the inhibition of cerussite flotation by excessive sulfide ions. Moreover, it also revealed that sulfide ions in the pulp solution were transformed onto the mineral surface and formed lead sulfide species. These results showed that both of lead sulfide species and its activity acted as an important role in sulfidization flotation process of cerussite.

Adsorption of sulfide ions on cerussite surfaces and implications for flotation

Energy Technology Data Exchange (ETDEWEB)

Feng, Qicheng [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093 (China); Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Wen, Shuming, E-mail: fqckmust@126.com [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093 (China); Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Zhao, Wenjuan [Kunming Metallurgical Research Institute, Kunming 650031 (China); Deng, Jiushuai; Xian, Yongjun [State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization, Kunming University of Science and Technology, Kunming 650093 (China); Faculty of Land Resource Engineering, Kunming University of Science and Technology, Kunming 650093 (China)

2016-01-01

Highlights: • A new discussion on the lead sulfide species is introduced. • The Na{sub 2}S concentration determines cerussite sulfidization. • The activity of lead sulfide species also determines cerussite sulfidization. • Disulfide and polysulfide in lead sulfide species affect its activity. - Abstract: The adsorption of sulfide ions on cerussite surfaces and implications for flotation were studied by X-ray photoelectron spectroscopy (XPS) analysis, micro-flotation tests, and surface adsorption experiments. The XPS analysis results indicated that lead sulfide species formed on the mineral surface after treatment by Na{sub 2}S, and the increase in the Na{sub 2}S concentration was beneficial for sulfidization. In addition to the content of lead sulfide species, its activity, which was determined by the proportion of sulfide, disulfide and polysulfide, also played an important role in cerussite sulfidization. Micro-flotation tests results demonstrated that insufficient or excessive addition of Na{sub 2}S in pulp solutions has detrimental effects on flotation performance, which was attributed to the dosage of Na{sub 2}S and the activity of lead sulfide species formed on the mineral surface. Surface adsorption experiments of sulfide ions determined the residual S concentrations in pulp solutions and provided a quantitative illustration for the inhibition of cerussite flotation by excessive sulfide ions. Moreover, it also revealed that sulfide ions in the pulp solution were transformed onto the mineral surface and formed lead sulfide species. These results showed that both of lead sulfide species and its activity acted as an important role in sulfidization flotation process of cerussite.

Sensitivity of single contrast barium enema with regard to colorectal disease as diagnosed by colonoscopy

International Nuclear Information System (INIS)

Kaude, J.V.; Harty, R.F.

1982-01-01

The results of single contrast barium enema were retrospectively correlated with colonoscopically diagnosed colorectal disease in 54 patients (75 lesions). Altogether 66 lesions (88%) were correctly diagnosed. The sensitivity of barium enema for polyps was 81% (26/32). There were three perceptive errors and three polyps 5 mm or less in size were not demonstrated by barium enema. Twenty-nine cases of inflammatory disorders were all correctly diagnosed. One of 12 malignancies was missed by perceptive error. In two cases with vascular malformations the barium enema was normal. 4/9 (44%) of missed lesions were perceptive errors and could have been probably avoided by a second independent reading of films. (orig.)

Efficacy of Barium-Based Fecal Tagging for CT Colonography: a Comparison between the Use of High and Low Density Barium Suspensions in a Korean Population - a Preliminary Study

Science.gov (United States)

Kim, Min Ju; Lee, Seung Soo; Byeon, Jeong-Sik; Choi, Eugene K.; Kim, Jung Hoon; Kim, Yeoung Nam; Kim, Ah Young; Ha, Hyun Kwon

2009-01-01

Objective This preliminarily study was designed to determine and to compare the efficacy of two commercially available barium-based fecal tagging agents for CT colonography (CTC) (high-density [40% w/v] and low-density [4.6% w/v] barium suspensions) in a population in Korea. Materials and Methods In a population with an identified with an average-risk for colorectal cancer, 15 adults were administered three doses of 20 ml 40% w/v barium for fecal tagging (group I) and 15 adults were administered three doses of 200 ml 4.6% w/v barium (group II) for fecal tagging. Excluding five patients in group I and one patient in group II that left the study, ten patients in group I and 14 patients in group II were finally included in the analysis. Two experienced readers evaluated the CTC images in consensus regarding the degree of tagging of stool pieces 6 mm or larger. Stool pieces were confirmed with the use of standardized CTC criteria or the absence of matched lesions as seen on colonoscopy. The rates of complete fecal tagging were analyzed on a per-lesion and a per-segment basis and were compared between the patients in the two groups. Results Per-lesion rates of complete fecal tagging were 52% (22 of 42; 95% CI, 37.7-66.6%) in group I and 78% (28 of 36; 95% CI, 61.7-88.5%) in group II. The difference between the two groups did not reach statistical significance (p = 0.285). The per-segment rates of complete tagging were 33% (6 of 18; 95% CI, 16.1%-56.4%) in group I and 60% (9 of 15; 95% CI, 35.7%-80.3%) in group II; again, the difference between the two groups did not reach statistical significance (p = 0.171). Conclusion Barium-based fecal tagging using both the 40% w/v and the 4.6% w/v barium suspensions showed moderate tagging efficacy. The preliminary comparison did not demonstrate a statistically significant difference in the tagging efficacy between the use of the two tagging agents, despite the tendency toward better tagging with the use of the 4.6% w/v barium

Spectrophotometry of barium, CH, and R-type carbon stars

International Nuclear Information System (INIS)

Gow, C.E.

1976-01-01

Observations of 35 barium, CH, R, and hydrogen-deficient carbon stars, along with ten comparison K giants, have been made with the Indiana rapid spectrum scanner and the Indiana SIT vidicon spectrometer. The scanner observations cover a wavelength range of 3300--7000 A at 30-A resolution, while the SIT vidicon observations cover a wavelength range of 3800--5000 A at 2.5-A resolution. The data have been used to form molecular indices for a quantitative measurement of the strength of molecular features appearing in this region of the spectrum, and to compare the spectral energy distribution of carbon and oxygen stars over the entire observed wavelength range. We find the C 2 Swan index correlated strongly with both the strength of an unidentified feature centered near 4000 A, and the barium-to-hydrogen ratio. A detailed comparison of the spectral energy distribution of the barium stars with normal K giants shows that this unidentified absorption feature consists of two shallows depressions, one at 4000 A and another at 4325 A

Comparative evaluation of the fecal-tagging quality in CT colonography: barium vs. iodinated oral contrast agent.

Science.gov (United States)

Nagata, Koichi; Singh, Anand Kumar; Sangwaiya, Minal Jagtiani; Näppi, Janne; Zalis, Michael E; Cai, Wenli; Yoshida, Hiroyuki

2009-11-01

The purpose of this evaluation was to compare the tagging quality of a barium-based regimen with that of iodine-based regimens for computed tomographic (CT) colonography. Tagging quality was assessed retrospectively in three different types of fecal-tagging CT colonographic cases: 24 barium-based cases, 22 nonionic iodine-based cases, and 24 ionic iodine-based cases. For the purpose of evaluation, the large intestine was divided into six segments, and the tagging homogeneity of a total of 420 segments (70 patients) was graded by three blinded readers from 0 (heterogeneous) to 4 (homogeneous). For barium-based cases, the average score for the three readers was 2.4, whereas it was 3.4 for nonionic iodine and 3.6 for ionic iodine. The percentages of segments that were assigned scores of 4 (excellent tagging [100%]) were 11.6%, 61.9%, and 72.9% for the barium-based, nonionic iodine-based, and ionic iodine-based regimens, respectively. The homogeneity scores of iodine-based fecal-tagging regimens were significantly higher than those of the barium-based fecal-tagging regimen (P barium-based regimen (P barium-based fecal-tagging regimen. Iodine-based fecal-tagging regimens can provide an appropriate method for use in nonlaxative or minimum-laxative CT colonography.

The efficacy of steroids for postoperative persistent inflammatory reaction in a patient with barium peritonitis: A case report

Directory of Open Access Journals (Sweden)

Hirofumi Kojima

2017-01-01

Conclusion: Residual barium in the intraperitoneal cavity causes persistent inflammatory reaction in patients with barium peritonitis. The use of steroids is effective for postoperative persistent inflammation due to the residual barium.

Structure and multiferroic properties of barium hexaferrite ceramics

International Nuclear Information System (INIS)

Tan, Guolong; Chen, Xiuna

2013-01-01

Simultaneous occurrence of large ferroelectricity and strong ferromagnetism have been observed in barium hexaferrite ceramics. Barium hexaferrite (BaFe 12 O 19 ) powders with hexagonal crystal structure were successfully synthesized in a polymer precursor method using barium acetate and ferric acetylacetonate as the precursors. The powders were pressed into pellets which were sintered into ceramics at 1200 °C and 1300 °C for 1 h. The structure and morphology of the ceramics were examined using X-ray diffraction and field emission scanning electron microscopy. Large spontaneous polarization was observed in the BaFe 12 O 19 ceramics at room temperature, revealing a clear ferroelectric hysteresis loop. The maximum remanent polarization of the BaFe 12 O 19 ceramic was estimated approximately 11.8 μC cm −2 . The FeO 6 octahedron in its perovskite-like hexagonal unit cell and the shift of Fe 3+ off the center of octahedron are suggested to be the origin of the polarization in BaFe 12 O 19 . The BaFe 12 O 19 ceramics also showed strong ferromagnetism at room temperature. - Graphical abstract: Ferroelectric hysteresis loops of BaFe 12 O 19 ceramics measured at a frequency of 120 Hz, which shows that the ceramics sintered at 1200 °C is ferroelectric with P r ∼11.8 μC/cm 2 . Highlights: ► Large ferroelectricity and strong ferromagnetism were observed in barium hexaferrite ceramics. ► The maximum remanent polarization of the BaFe 12 O 19 ceramic was estimated to be 11.8 μC cm −2 . ► The FeO 6 octahedron and off-center shift of Fe 3+ are suggested to be the origin of the polarization.

The reaction between barium and nitrogen in liquid sodium: resistivity studies

International Nuclear Information System (INIS)

Addison, C.C.; Creffield, G.K.; Hubberstey, P.; Pulham, R.J.

1976-01-01

The reaction of nitrogen with solutions of barium (between 0.34 and 6.89 mol % Ba) in liquid sodium at 573 K has been followed by changes in the electrical resistivity of the liquid. The capillary method has been employed, continuous sampling during reaction being achieved by electromagnetic pumping. The initial solution of nitrogen in the metal, followed by precipitation of barium and nitrogen from sodium as the nitride Ba 2 N, are reflected in the resistivity changes. The solubility of nitrogen in the alloy is a linear function of the barium concentration: S(mol % N) = x/4 (0 <= x <= 6.89 mol % Ba). This and the decrease in resistivity which invariably occurs during the solution process, provides additional information on the nature of solvation of nitrogen in solution in the liquid metal. (author)

Virtual colonoscopy with electron beam CT: correlation with barium enema, colonoscopy and pathology

International Nuclear Information System (INIS)

Hong, Hye Suk; Kim, Min Jung; Chung, Jae Joon; Kim, Myeong Jin; Lee, Jong Tae; Yoo, Hyung Sik

1998-01-01

To perform virtual colonoscopy using electron beam tomography(EBT) in patients in whom a colonic mass was present, and to compare the results with those obtained using barium enema, colonoscopy and gross pathologic specimens. Materials and Methods : Ten patients in whom colonic masses were diagnosed by either barium enema or colonoscopy were involved in this study. There were nine cases of adenocarcinoma and one of tubulovillous adenoma. Using EBT preoperative abdominopelvic CT scans were performed. Axial scans were then three-dimensionally reconstructed to produce virtual colonoscopic images and were compared with barium enema, colonoscopy and gross pathologic specimens. Virtual colonoscopic images of the masses were classified as either 1)polyploid, 2)sessile,3)fungating, or 4)annular constrictive. We also determined whether ulcers were present within the lesions and whether there was obstruction. Results : After virtual colonoscopy, two lesions were classified as polyploid, one as sessile, five as fungating and two as annular constrictive. Virtual colonoscopic images showed good correlation with the findings of barium enema, colonoscopy and gross pathologic specimens. Three of six ulcerative lesions were observed on colonoscopy; in seven adenocarcinomas with partial or total luminal obstruction, virtual colonoscopy visualized the colon beyond the obstructed sites. In one case, barium contrast failed to pass through the obstructed portion and in six cases, the colonoscope similarly failed. Conclusion : Virtual colonoscopies correlated well with barium enema, colonoscopy and gross pathologic specimens. They provide three dimensional images of colonic masses and are helpful for the evaluation of obstructive lesions

Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

International Nuclear Information System (INIS)

Taylor, S.A.; Halligan, S.; Burling, D.; Bassett, P.; Bartram, C.I.

2005-01-01

AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients

Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

Energy Technology Data Exchange (ETDEWEB)

Taylor, S.A. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)]. E-mail: csytaylor@yahoo.co.uk; Halligan, S. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Burling, D. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bassett, P. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bartram, C.I. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)

2005-02-01

AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients.

Spectroscopic (multi-energy) CT distinguishes iodine and barium contrast material in MICE

CERN Document Server

Anderson, NG; Firsching, M; de Ruiter, N; Schleich, N; Butzer, J S; Cook, N J; Grasset, R; Campbell, M; Scott, N J A; Anderson, N G

2010-01-01

Spectral CT differs from dual-energy CT by using a conventional X-ray tube and a photon-counting detector. We wished to produce 3D spectroscopic images of mice that distinguished calcium, iodine and barium. We developed a desktop spectral CT, dubbed MARS, based around the Medipix2 photon-counting energy-discriminating detector. The single conventional X-ray tube operated at constant voltage (75 kVp) and constant current (150 A mu A). We anaesthetised with ketamine six black mice (C57BL/6). We introduced iodinated contrast material and barium sulphate into the vascular system, alimentary tract and respiratory tract as we euthanised them. The mice were preserved in resin and imaged at four detector energy levels from 12 keV to 42 keV to include the K-edges of iodine (33.0 keV) and barium (37.4 keV). Principal component analysis was applied to reconstructed images to identify components with independent energy response, then displayed in 2D and 3D. Iodinated and barium contrast material was spectrally distinct f...

Imaging assessment of the modified double contrast barium enema using carboxymethylcellulose on radiography and ultrasonography in dogs.

Science.gov (United States)

Choi, Mihyun; Lee, Namsoon; Kim, Junyoung; Yi, Kangjae; Jung, Joohyun; Yoon, Junghee; Choi, Mincheol

2011-01-01

A modified double contrast barium enema using carboxymethylcellulose was evaluated in beagle dogs and compared with dogs receiving a conventional barium enema. The experimental group was divided into three groups (1, 2, and 3) and given 30 ml/kg of different volume ratios of a barium vs. carboxymethylcellulose mixture. Each group underwent sonography following radiography. The volume ratio of one part barium to three parts carboxymethylcellulose was judged to be the optimal mixture, resulting in a general distribution of contrast and bowel radiolucency on radiographs and adequate postradiography sonography. The modified barium enema using carboxymethylcellulose is useful for assessing the general morphology and mucosal layers of the colon simultaneously on radiographs and ultrasonographs.

Acute respiratory failure caused by aspiration of high density barium: A case report

International Nuclear Information System (INIS)

Park, Ki Soon; Jung, Eun A; Yang, Ik; Lee, Yul; Chung, Soo Young

1994-01-01

Accidental aspiration of barium contrast medium during the upper gastrointestinal study can occur in patients with swallowing disorder, especially in the elderly patients. We experienced a case of respiratory failure followed by death within a few hours in 85 year-old patient after barium aspiration

Imaging diagnosis--duodenobiliary reflux of barium sulfate during esophagogastrography in a dog.

Science.gov (United States)

Shaikh, Layla; Sharma, Ajay; Secrest, Scott

2015-01-01

A 4-year-old Australian cattle dog presented for regurgitation, 2 months after duodenal resection and anastomosis for a perforated duodenal ulcer. Duodenobiliary reflux of barium sulfate suspension was detected during fluoroscopic esophagogastrography. Follow-up radiography 2 hours later demonstrated persistence of the barium in the gallbladder and biliary tree. Ultrasonography showed an open sphincter of Oddi but no other morphological abnormalities with the gallbladder or biliary system. No side effects or bloodwork abnormalities were noted. This is the first case report of duodenobiliary reflux of barium in a dog. The pathophysiology of this phenomenon and its incidence and significance in human medicine are discussed. © 2014 American College of Veterinary Radiology.

Prospective comparison of air-contrast barium enema and colonoscopy in patients with fecal occult blood: a pilot study.

Science.gov (United States)

Rockey, Don C; Koch, Johannes; Yee, Judy; McQuaid, Kenneth R; Halvorsen, Robert A

2004-12-01

The utility of air-contrast barium enema and colonoscopy for evaluation of the colon has been debated. Air-contrast barium enema is less expensive and invasive than colonoscopy, but it also is less sensitive and specific. Further, although air-contrast barium enema may be less painful than colonoscopy, it often is poorly tolerated by patients. Thus, this study compared the sensitivity and the specificity of air-contrast barium enema and colonoscopy for detection of colonic lesions in patients with fecal occult blood. Over a 30-month period, patients with fecal occult blood were recruited. Patients underwent standard air-contrast barium enema, followed by colonoscopy 7 to 14 days later. Colonoscopists were blinded to the results of air-contrast barium enema until the colonoscopy was completed, after which the results were disclosed. If the findings were discrepant, colonoscopy was repeated. A total of 100 patients were evaluated. Nine air-contrast barium enemas were reported to be inadequate, and the cecum was not intubated at colonoscopy in two patients. In the remaining patients, 5 cancers were identified (1 each cecum, transverse colon, descending colon, sigmoid colon, and rectum) by both studies. Sixty-six polypoid lesions were identified in 30 patients. Diverticula were identified in 42 patients by air-contrast barium enema and in 18 patients by colonoscopy. Air-contrast barium enema detected 3 of 36 polypoid lesions 5 mm or less in diameter, 5 of 15 adenomas 6 to 9 mm in size, and 4 of 15 adenomas 10 mm or greater in diameter (sensitivity 8%, 33%, and 27%, respectively). After excluding patients with diverticula, air-contrast barium enema detected 3 of 7 adenomas 10 mm or greater in size. Overall, 12 polypoid lesions or filling defects were identified by air-contrast barium enema that could not be verified by colonoscopy. The specificity of air-contrast barium enema for lesions 1.0 cm or greater in size was 100%; for those 6 mm or greater, it was 97%. Air

The Kerr nonlinearity of the beta-barium borate crystal

DEFF Research Database (Denmark)

Bache, Morten; Guo, Hairun; Zhou, Binbin

2013-01-01

A popular crystal for ultrafast cascading experiments is beta-barium-borate (β-BaB2O4, BBO). It has a decent quadratic nonlinear coefficient, and because the crystal is anisotropie it can be birefringence phase-matched for type I (oo → e) second-harmonic generation (SHG). For femtosecond experime......A popular crystal for ultrafast cascading experiments is beta-barium-borate (β-BaB2O4, BBO). It has a decent quadratic nonlinear coefficient, and because the crystal is anisotropie it can be birefringence phase-matched for type I (oo → e) second-harmonic generation (SHG). For femtosecond...

Comparison of barium swallow and ultrasound in diagnosis of gastro-oesophageal reflux in children.

Science.gov (United States)

Naik, D R; Bolia, A; Moore, D J

1985-01-01

Fifty one infants and older children with suspected gastro-oesophageal reflux entered a study comparing the diagnostic accuracy of a standard barium swallow examination with that of ultrasound scanning. All children were examined by both techniques. In 40 cases there was unequivocal agreement between the examinations. Of the remaining patients, four had definite reflux by ultrasonic criteria but showed no evidence of reflux on barium swallow examination, four had positive findings on ultrasound but showed only minimal reflux on barium swallow, and one showed minimal reflux on ultrasound but had a negative barium meal result. In two children the ultrasound study was inconclusive. Ultrasound has an important role in the diagnosis and follow up of patients under the age of 5 years with gastro-oesophageal reflux. Images FIG 1 FIG 2 PMID:3924317

Microwave-hydrothermal synthesis of barium strontium titanate nanoparticles

International Nuclear Information System (INIS)

Simoes, A.Z.; Moura, F.; Onofre, T.B.; Ramirez, M.A.; Varela, J.A.; Longo, E.

2010-01-01

Research highlights: → Barium strontium titanate nanoparticles were obtained by the Hydrothemal microwave technique (HTMW) → This is a genuine technique to obtain nanoparticles at low temperature and short times → Barium strontium titanate free of carbonates with tetragonal structure was grown at 130 o C. - Abstract: Hydrothermal-microwave method (HTMW) was used to synthesize crystalline barium strontium titanate (Ba 0.8 Sr 0.2 TiO 3 ) nanoparticles (BST) in the temperature range of 100-130 o C. The crystallization of BST with tetragonal structure was reached at all the synthesis temperatures along with the formation of BaCO 3 as a minor impurity at lower syntheses temperatures. Typical FT-IR spectra for tetragonal (BST) nanoparticles presented well defined bands, indicating a substantial short-range order in the system. TG-DTA analyses confirmed the presence of lattice OH- groups, commonly found in materials obtained by HTMW process. FE/SEM revealed that lower syntheses temperatures led to a morphology that consisted of uniform grains while higher syntheses temperature consisted of big grains isolated and embedded in a matrix of small grains. TEM has shown BST nanoparticles with diameters between 40 and 80 nm. These results show that the HTMW synthesis route is rapid, cost effective, and could serve as an alternative to obtain BST nanoparticles.

Use of biogenic sulfide for ZnS precipitation

NARCIS (Netherlands)

Esposito, G.; Veeken, A.; Weijma, J.; Lens, P.N.L.

2006-01-01

A 600 ml continuously stirred tank reactor was used to assess the performance of a zinc sulfide precipitation process using a biogenic sulfide solution (the effluent of a sulfate-reducing bioreactor) as sulfide source. In all experiments, a proportional-integral (PI) control algorithm was used to

Recovery and separation of rare-earth elements, barium, and strontium from bastnasite with sulfuric acid

International Nuclear Information System (INIS)

Eisele, J.A.; Bauer, D.J.

1974-01-01

A bench-scale investigation was made of a concentrated H 2 SO 4 reaction for recovering and separating rare earth elements, barium, and strontium from a bastnaesite ore and byproduct. Barium and strontium were dissolved in the concentrated acid and precipitated as a mixed product by water dilution. Separation of strontium from barium was effected by reaction with Na 2 CO 3 solution, followed by a dilute acid leach of the SrCO 3 formed. After removing the barium and strontium from bastnaesite ore, the rare-earth elements were roasted to water-soluble sulfates. The rare earth sulfate solution was subsequently processed by solvent extraction to produce rare-earth oxides low in lead and magnesium. (U.S.)

Microaeration for hydrogen sulfide removal in UASB reactor.

Science.gov (United States)

Krayzelova, Lucie; Bartacek, Jan; Kolesarova, Nina; Jenicek, Pavel

2014-11-01

The removal of hydrogen sulfide from biogas by microaeration was studied in Up-flow Anaerobic Sludge Blanket (UASB) reactors treating synthetic brewery wastewater. A fully anaerobic UASB reactor served as a control while air was dosed into a microaerobic UASB reactor (UMSB). After a year of operation, sulfur balance was described in both reactors. In UASB, sulfur was mainly presented in the effluent as sulfide (49%) and in biogas as hydrogen sulfide (34%). In UMSB, 74% of sulfur was detected in the effluent (41% being sulfide and 33% being elemental sulfur), 10% accumulated in headspace as elemental sulfur and 9% escaped in biogas as hydrogen sulfide. The efficiency of hydrogen sulfide removal in UMSB was on average 73%. Microaeration did not cause any decrease in COD removal or methanogenic activity in UMSB and the elemental sulfur produced by microaeration did not accumulate in granular sludge. Copyright © 2014 Elsevier Ltd. All rights reserved.

Sulfide toxicity kinetics of a uasb reactor

Directory of Open Access Journals (Sweden)

D. R. Paula Jr.

2009-12-01

Full Text Available The effect of sulfide toxicity on kinetic parameters of anaerobic organic matter removal in a UASB (up-flow anaerobic sludge blanket reactor is presented. Two lab-scale UASB reactors (10.5 L were operated continuously during 12 months. The reactors were fed with synthetic wastes prepared daily using glucose, ammonium acetate, methanol and nutrient solution. One of the reactors also received increasing concentrations of sodium sulfide. For both reactors, the flow rate of 16 L.d-1 was held constant throughout the experiment, corresponding to a hydraulic retention time of 15.6 hours. The classic model for non-competitive sulfide inhibition was applied to the experimental data for determining the overall kinetic parameter of specific substrate utilization (q and the sulfide inhibition coefficient (Ki. The application of the kinetic parameters determined allows prediction of methanogenesis inhibition and thus the adoption of operating parameters to minimize sulfide toxicity in UASB reactors.

Sulfide Precipitation in Wastewater at Short Timescales

DEFF Research Database (Denmark)

Kiilerich, Bruno; van de Ven, Wilbert; Nielsen, Asbjørn Haaning

2017-01-01

Abatement of sulfides in sewer systems using iron salts is a widely used strategy. When dosing at the end of a pumping main, the reaction kinetics of sulfide precipitation becomes important. Traditionally the reaction has been assumed to be rapid or even instantaneous. This work shows that this i......Abatement of sulfides in sewer systems using iron salts is a widely used strategy. When dosing at the end of a pumping main, the reaction kinetics of sulfide precipitation becomes important. Traditionally the reaction has been assumed to be rapid or even instantaneous. This work shows...... that this is not the case for sulfide precipitation by ferric iron. Instead, the reaction time was found to be on a timescale where it must be considered when performing end-of-pipe treatment. For real wastewaters at pH 7, a stoichiometric ratio around 14 mol Fe(II) (mol S(−II))−1 was obtained after 1.5 s, while the ratio...

Comparison of Calcium and Barium Microcapsules as Scaffolds in the Development of Artificial Dermal Papillae.

Science.gov (United States)

Liu, Yang; Lin, Changmin; Zeng, Yang; Li, Haihong; Cai, Bozhi; Huang, Keng; Yuan, Yanping; Li, Yu

2016-01-01

This study aimed to develop and evaluate barium and calcium microcapsules as candidates for scaffolding in artificial dermal papilla. Dermal papilla cells (DPCs) were isolated and cultured by one-step collagenase treatment. The DPC-Ba and DPC-Ca microcapsules were prepared by using a specially designed, high-voltage, electric-field droplet generator. Selected microcapsules were assessed for long-term inductive properties with xenotransplantation into Sprague-Dawley rat ears. Both barium and calcium microcapsules maintained xenogenic dermal papilla cells in an immunoisolated environment and induced the formation of hair follicle structures. Calcium microcapsules showed better biocompatibility, permeability, and cell viability in comparison with barium microcapsules. Before 18 weeks, calcium microcapsules gathered together, with no substantial immune response. After 32 weeks, some microcapsules were near inflammatory cells and wrapped with fiber. A few large hair follicles were found. Control samples showed no marked changes at the implantation site. Barium microcapsules were superior to calcium microcapsules in structural and mechanical stability. The cells encapsulated in hydrogel barium microcapsules exhibited higher short-term viability. This study established a model to culture DPCs in 3D culture conditions. Barium microcapsules may be useful in short-term transplantation study. Calcium microcapsules may provide an effective scaffold for the development of artificial dermal papilla.

Biodegradation of BTEX and Other Petroleum Hydrocarbons by Enhanced and Controlled Sulfate Reduction

Energy Technology Data Exchange (ETDEWEB)

Song Jin

2007-07-01

High concentrations of sulfide in the groundwater at a field site near South Lovedale, OK, were inhibiting sulfate reducing bacteria (SRB) that are known to degrade contaminants including benzene, toluene, ethylbenzene, and m+p-xylenes (BTEX). Microcosms were established in the laboratory using groundwater and sediment collected from the field site and amended with various nutrient, substrate, and inhibitor treatments. All microcosms were initially amended with FeCl{sub 2} to induce FeS precipitation and, thereby, reduce sulfide concentrations. Complete removal of BTEX was observed within 39 days in treatments with various combinations of nutrient and substrate amendments. Results indicate that elevated concentration of sulfide is a limiting factor to BTEX biodegradation at this site, and that treating the groundwater with FeCl{sub 2} is an effective remedy to facilitate and enhance BTEX degradation by the indigenous SRB population. On another site in Moore, OK, studies were conducted to investigate barium in the groundwater. BTEX biodegradation by SRB is suspected to mobilize barium from its precipitants in groundwater. Data from microcosms demonstrated instantaneous precipitation of barium when sulfate was added; however, barium was detected redissolving for a short period and precipitating eventually, when active sulfate reduction was occurring and BTEX was degraded through the process. SEM elemental spectra of the evolved show that sulfur was not present, which may exclude BaSO{sub 4} and BaS as a possible precipitates. The XRD analysis suggests that barium probably ended in BaS complexing with other amorphous species. Results from this study suggest that SRB may be able to use the sulfate from barite (BaSO{sub 4}) as an electron acceptor, resulting in the release of free barium ions (Ba{sup 2+}), and re-precipitate it in BaS, which exposes more toxicity to human and ecological health.

Effect of barium-coated halloysite nanotube addition on the cytocompatibility, mechanical and contrast properties of poly(methyl methacrylate) cement.

Science.gov (United States)

Jammalamadaka, Uday; Tappa, Karthik; Weisman, Jeffery A; Nicholson, James Connor; Mills, David K

2017-01-01

Halloysite nanotubes (HNTs) were investigated as a platform for tunable nanoparticle composition and enhanced opacity in poly(methyl methacrylate) (PMMA) bone cement. Halloysite has been widely used to increase the mechanical properties of various polymer matrices, in stark contrast to other fillers such as barium sulfate that provide opacity but also decrease mechanical strength. The present work describes a dry deposition method for successively fabricating barium sulfate nanoparticles onto the exterior surface of HNTs. A sintering process was used to coat the HNTs in barium sulfate. Barium sulfate-coated HNTs were then added to PMMA bone cement and the samples were tested for mechanical strength and tailored opacity correlated with the fabrication ratio and the amount of barium sulfate-coated HNTs added. The potential cytotoxic effect of barium-coated HNTs in PMMA cement was also tested on osteosarcoma cells. Barium-coated HNTs were found to be completely cytocompatible, and cell proliferation was not inhibited after exposure to the barium-coated HNTs embedded in PMMA cement. We demonstrate a simple method for the creation of barium-coated nanoparticles that imparted improved contrast and material properties to native PMMA. An easy and efficient method for coating clay nanotubes offers the potential for enhanced imaging by radiologists or orthopedic surgeons.

[Value of preoperative barium contrast examination for the diagnosis and operative planning in gastric cancer].

Science.gov (United States)

Wang, Chang-jian; Zhao, Guang-fa; Li, Qing-guo; Chen, Jing-gui; Zhu, Kai; Shi, Ying-qiang; Fu, Hong

2010-04-01

To investigate the value of preoperative barium contrast examination for the diagnosis and operative planning in gastric cancer. Clinical data of 229 gastric cancer patients were analyzed retrospectively. Lesions were divided into three parts: the cardiac, the body, and the antrum. The diagnostic accuracy of localization and the extent of tumor between gastroscopy alone and gastroscopy plus barium contrast were compared with the results of surgical findings. The diagnostic accuracy of localization and the extent of tumor for gastroscopy in the cardiac, the body and the antrum cancers were 100% and 78.4%, 94.6% and 86.5%, 98.1% and 84.6%, respectively, while for gastroscopy plus barium contrast were 100% and 84.8%, 100% and 91.9%, 99.0% and 90.4%, respectively. The diagnostic accuracy of both the localization and the extent of tumor were not significantly different between gastroscopy alone and gastroscopy plus barium contrast (P>0.05). Diagnostic accuracy of the length of esophagus infiltrated by cardiac cancer in gastroscopy was 60.6%, while in gastroscopy plus barium contrast was 90.9%, which was significantly different (Pbarium contrast was more accurate in predicting the possibility of thoracotomy in cardiac cancer infiltrating the lower esophagus. It is necessary to perform preoperative barium contrast examination in cardiac cancer patients, so as to identify whether the lower esophagus is infiltrated and to measure the length of lesion, which can provide evidences for making a decision of thoracotomy. For gastric body and antrum cancer, there is no indication for barium contrast examination if gastroscopy findings are satisfied.

Fluoroscopy-guided barium marking for localizing small pulmonary lesions before video-assisted thoracoscopic surgery

International Nuclear Information System (INIS)

Yamada, Takahiro; Koyama, Yasunori; Masui, Asami

2009-01-01

Small pulmonary lesions not previously seen on chest radiographs will likely be detected with increasing frequency because of the spread of CT screening. For the diagnosis and treatment of such lesions, we frequently perform resection by video-assisted thoracoscopic surgery (VATS). We performed fluoroscopy-guided barium marking for localization of small peripheral pulmonary lesions before VATS resection, and examined its reliability, safety, and usefulness. We studied 46 patients with peripheral pulmonary lesions 20 mm or less in diameter who were scheduled to undergo VATS resection. The average diameter of the lesions was 10.2±0.5 mm (mean±standard error), and the average distance from the pleural surface was 10.1±0.8 mm. The optimal site for the catheter tip was decided on chest radiographs using CT scans for reference beforehand, and a catheter was inserted bronchoscopically into the target segment and guided to the presumed lesion. A 50% (weight/volume) barium sulfate suspension was instilled into the bronchus through the catheter, and the site of barium marking was checked by CT scanning. The average instilled volume of barium was 0.36±0.03 ml. On CT scans, barium spots were superimposed on the target lesions in 35 of the 46 patients and were only 15 mm from the lesions in the other patients. Barium was well recognized in all patients at the time of VATS resection, and we could confirm the diagnosis in all patients. A mild cough persisted for about 1 week in 1 patient, but the other patients had no specific complications. Fluoroscopy-guided barium marking is a safe, convenient, and reliable method for localization of small pulmonary lesions before VATS resection. (author)

Benefits of Barium Enema in Patients with Incomplete Colonoscopy. Prospective Study of 45 Cases

International Nuclear Information System (INIS)

Gispert, S.; Mayolas, N.; Hidalgo, A.

2003-01-01

To evaluate the usefulness of barium enema in patients with incomplete colonoscopy. There was carried out a prospective 10-month study of 45 patients with incomplete colonoscopy (27 men and 18 women), who were later examined by means of barium enema (33 conventional, 12 double-contrast) in order to check for additional pathology in portions of the colon not visualized by colonoscopy. Barium enema diagnosed six possible additional lesions (13.3%) in portions of the colon not visualized by incomplete colonoscopy (four neoplasia and two non-neoplasia). Regarding the neoplasia two were true positives and two false positives. Both true positives were adenocarcinomas (one synchronous caecum, and another in splenic angle). The two false positives corresponded to fecal matter stuck to the intestinal wall. Regarding the non-neoplasia, multiple stenosis was detected in a patient with Crohn's disease and an enterocolic fistula was found in a patient with sigmoid colon neoplasia. The diagnostic yield of barium enema in the detection of additional pathology in colon portions not visualized by colonoscopy was of 9%. Barium enema following incomplete colonoscopy permits a complete colon evaluation in most cases, and it offers additional diagnostic information. (Author) 21 refs

Colonic transit time in patient with slow-transit constipation: Comparison of radiopaque markers and barium suspension method

Energy Technology Data Exchange (ETDEWEB)

Xu Huimin [Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University, No. 8 Gongtina Lu, Chaoyang District, Beijing 100020 (China); Department of General Surgery, Weifang People' s Hospital, ShanDong Province 261041 (China); Han Jiagang [Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University, No. 8 Gongtina Lu, Chaoyang District, Beijing 100020 (China); Na Ying [Department of Medical Imaging, Weifang People' s Hospital, ShanDong Province 261041 (China); Zhao Bo; Ma Huachong [Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University, No. 8 Gongtina Lu, Chaoyang District, Beijing 100020 (China); Wang Zhenjun, E-mail: wang3zj@sohu.com [Department of General Surgery, Beijing Chaoyang Hospital, Capital Medical University, No. 8 Gongtina Lu, Chaoyang District, Beijing 100020 (China)

2011-08-15

Background: Colonic transit study provides valuable information before surgical treatment is considered for patient with constipation. The radiopaque markers method is the most common way for evaluating colon transit time. The aim of this study is to compare the barium suspension with the radiopaque makers to assess the colonic mobility in patient with constipation. Methods: Colonic transit time was measured in 11 female patients with slow-transit constipation using both radiopaque markers and barium suspension method. In radiopaque markers method, the patient ingested 20 markers on the first day, and an abdominal radiograph was performed every 24 h until 80% markers were excreted. In barium suspension method, the patient swallowed up to 50 ml of 200% (w/v) barium meal. The abdominal radiographs were taken at the same time point as the former. Results: The total or segmental colonic transit time were obviously prolonged in all patients. Segmental transits time spent in the right colon, left colon and rectosigmoid for radiopaque markers and barium suspension method was, respectively, 30 {+-} 6 h and 34 {+-} 7 h; 38 {+-} 9 h and 32 {+-} 6 h; 40 {+-} 8 h and 38 {+-} 10 h. In the radiopaque markers method, total colonic transit time was 108 {+-} 14 h and it was 103 {+-} 13 h in the barium suspension method (P > 0.05). Conclusion: The barium suspension and radiopaque markers gave the similar results for colonic transit time. The barium suspension was a simple and cheap method for evaluating the colonic mobility.

Iron-sulfide crystals in probe deposits

DEFF Research Database (Denmark)

Laursen, Karin; Frandsen, Flemming

1998-01-01

Iron-sulfides were observed in deposits collected on a probe inserted at the top of the furnace of a coal-fired power station in Denmark. The chemical composition of the iron-sulfides is equivalent to pyrrhotite (FeS). The pyrrhotites are present as crystals and, based on the shape of the crystals......: (1) impact of low viscous droplets of iron sulfide; and (2) sulfur diffusion. Previous research on the influence of pyrite on slagging focused on the decomposition of pyrite into pyrrhotite and especially on the oxidation stage of this product during impact on the heat transfer surfaces...

Sulfide-conducting solid electrolytes

International Nuclear Information System (INIS)

Kalinina, L.A.; Shirokova, G.I.; Murin, I.V.; Ushakova, Yu.N.; Fominykh, E.G.; Lyalina, M.Yu.

2000-01-01

Feasibility of sulfide transfer in phases on the basis of BaZrS 3 and MLn 2 S 4 ( M = Ca, Ba; Ln = La, Y, Tm, Nd, Sm, Pr) is considered. Solid solution regions on the basis of ternary compounds are determined. Systematic study of the phases is carried out making use of the methods of conductometry, emf in chemical concentration chains without/with transfer, potentiostatic chronoamperometry. Possible mechanism of defect formation during successive alloying of ternary sulfides by binary ones in suggested [ru

Electromagnetic properties of photodefinable barium ferrite polymer composites

Science.gov (United States)

Sholiyi, Olusegun; Lee, Jaejin; Williams, John D.

2014-07-01

This article reports the magnetic and microwave properties of a Barium ferrite powder suspended in a polymer matrix. The sizes for Barium hexaferrite powder are 3-6 μm for coarse and 0.8-1.0 μm for the fine powder. Ratios 1:1 and 3:1 (by mass) of ferrite to SU8 samples were characterized and analyzed for predicting the necessary combinations of these powders with SU8 2000 Negative photoresist. The magnetization properties of these materials were equally determined and were analyzed using Vibrating Sample Magnetometer (VSM). The Thru, Reflect, Line (TRL) calibration technique was employed in determining complex relative permittivity and permeability of the powders and composites with SU8 between 26.5 and 40 GHz.

Electromagnetic properties of photodefinable barium ferrite polymer composites

Directory of Open Access Journals (Sweden)

Olusegun Sholiyi

2014-07-01

Full Text Available This article reports the magnetic and microwave properties of a Barium ferrite powder suspended in a polymer matrix. The sizes for Barium hexaferrite powder are 3–6 μm for coarse and 0.8–1.0 μm for the fine powder. Ratios 1:1 and 3:1 (by mass of ferrite to SU8 samples were characterized and analyzed for predicting the necessary combinations of these powders with SU8 2000 Negative photoresist. The magnetization properties of these materials were equally determined and were analyzed using Vibrating Sample Magnetometer (VSM. The Thru, Reflect, Line (TRL calibration technique was employed in determining complex relative permittivity and permeability of the powders and composites with SU8 between 26.5 and 40 GHz.

NASA/Max Planck Institute Barium Ion Cloud Project.

Science.gov (United States)

Brence, W. A.; Carr, R. E.; Gerlach, J. C.; Neuss, H.

1973-01-01

NASA and the Max Planck Institute for Extraterrestrial Physics (MPE), Munich, Germany, conducted a cooperative experiment involving the release and study of a barium cloud at 31,500 km altitude near the equatorial plane. The release was made near local magnetic midnight on Sept. 21, 1971. The MPE-built spacecraft contained a canister of 16 kg of Ba CuO mixture, a two-axis magnetometer, and other payload instrumentation. The objectives of the experiment were to investigate the interaction of the ionized barium cloud with the ambient medium and to deduce the properties of electric fields in the proximity of the release. An overview of the project is given to briefly summarize the organization, responsibilities, objectives, instrumentation, and operational aspects of the project.

Anoxic sulfide biooxidation using nitrite as electron acceptor

International Nuclear Information System (INIS)

Mahmood, Qaisar; Zheng Ping; Cai Jing; Wu Donglei; Hu, Baolan; Li Jinye

2007-01-01

Biotechnology can be used to assess the well being of ecosystems, transform pollutants into benign substances, generate biodegradable materials from renewable sources, and develop environmentally safe manufacturing and disposal processes. Simultaneous elimination of sulfide and nitrite from synthetic wastewaters was investigated using a bioreactor. A laboratory scale anoxic sulfide-oxidizing (ASO) reactor was operated for 135 days to evaluate the potential for volumetric loading rates, effect of hydraulic retention time (HRT) and substrate concentration on the process performance. The maximal sulfide and nitrite removal rates were achieved to be 13.82 and 16.311 kg/(m 3 day), respectively, at 0.10 day HRT. The process can endure high sulfide concentrations, as the sulfide removal percentage always remained higher than 88.97% with influent concentration up to 1920 mg/L. Incomplete sulfide oxidation took place due to lower consumed nitrite to sulfide ratios of 0.93. It also tolerated high nitrite concentration up to 2265.25 mg/L. The potential achieved by decreasing HRT at fixed substrate concentration is higher than that by increasing substrate concentration at fixed HRT. The process can bear short HRT of 0.10 day but careful operation is needed. Nitrite conversion was more sensitive to HRT than sulfide conversion when HRT was decreased from 1.50 to 0.08 day. Stoichiometric analyses and results of batch experiments show that major part of sulfide (89-90%) was reduced by nitrite while some autooxidation (10-11%) was resulted from presence of small quantities of dissolved oxygen in the influent wastewater. There was ammonia amassing in considerably high amounts in the bioreactor when the influent nitrite concentration reached above 2265.25 mg/L. High ammonia concentrations (200-550 mg/L) in the bioreactor contributed towards the overall inhibition of the process. Present biotechnology exhibits practical value with a high potential for simultaneous removal of nitrite

The impact of high-density barium use in double contrast radiographic methods for gastric cancer screening in Niigata, Japan.

Science.gov (United States)

Wakai, Shizuko; Tanabe, Naohito; Suzuki, Hiroshi

2005-04-01

Use of high-density barium (= or > 180 w/v%) has been widely spread in community-based mass screening for gastric cancer in Japan. However, the impact on outcomes of the screening has not been fully evaluated. Then, we investigated the advantage of high-density barium use by comparing the outcomes between a period with high-density barium and that with low-density barium (barium decreases the positive finding rate in initial mass screening x-ray examinations by 12% (odds ratio, 0.88; 95% confidence interval, 0.86 - 0.90) and increase the gastric cancer detection rate by diagnostic examination by 15% (odds ratio, 1.15; 95% confidence interval, 1.01-1.31). We conclude that introduction of high-density barium has improved the efficiency of mass screening for gastric cancer by decreasing unnecessary diagnostic examinations and reducing the total personal and public health costs. Thus, nationwide use of high-density barium is recommended for mass gastric cancer screening in Japan.

Oxidation and Precipitation of Sulfide in Sewer Networks

DEFF Research Database (Denmark)

Nielsen, A. H.

risks and corrosion of concrete and metals. Most of the problems relate to the buildup of hydrogen sulfide in the atmosphere of sewer networks. In this respect, the processes of the sulfur cycle are of fundamental importance in ultimately determining the extent of such problems. This study focused...... calibrated and validated against field data. In the extension to the WATS model, sulfur transformations were described by six processes: 1. Sulfide production taking place in the biofilm and sediments covering the permanently wetted sewer walls; 2. Biological sulfide oxidation in the permanently wetted...... to the sewer atmosphere, potentially resulting in concrete corrosion. The extended WATS model represents a major improvement over previously developed models for prediction of sulfide buildup in sewer networks. Compared to such models, the major processes governing sulfide buildup in sewer networks...

Kinetic Spectrophotometric Determination of Trace Amounts of Sulfide

Energy Technology Data Exchange (ETDEWEB)

Barzegar, Mohsen [Tarbiat Modarres University, Tehran (Iran, Islamic Republic of); Jabbari, Ali [K. N. Toosi University, Tehran (Iran, Islamic Republic of); Esmaeili, Majid [Razi University, Kermanshah (Iran, Islamic Republic of)

2003-09-15

A method for the determination of trace amount of sulfide based on the addition reaction of sulfide with methyl green at pH 7.5 and 25 .deg. C is described. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of the dyestuff at 637 nm by the initial rate and fixed time method. The calibration graph is linear in the range 30-1200 ppb. The theoretical limit of detection was 0.014 ppm. Seven replicate analysis of a sample solution containing 0.70 ppm sulfide gave a relative standard deviation of 1.5%. The interfering effects of various ions on sulfide determination have been reported and procedures for removal of interference have been described. The proposed method was applied successfully to the determination of sulfide in tap and wastewater samples.

Kinetic Spectrophotometric Determination of Trace Amounts of Sulfide

International Nuclear Information System (INIS)

Barzegar, Mohsen; Jabbari, Ali; Esmaeili, Majid

2003-01-01

A method for the determination of trace amount of sulfide based on the addition reaction of sulfide with methyl green at pH 7.5 and 25 .deg. C is described. The reaction is monitored spectrophotometrically by measuring the decrease in absorbance of the dyestuff at 637 nm by the initial rate and fixed time method. The calibration graph is linear in the range 30-1200 ppb. The theoretical limit of detection was 0.014 ppm. Seven replicate analysis of a sample solution containing 0.70 ppm sulfide gave a relative standard deviation of 1.5%. The interfering effects of various ions on sulfide determination have been reported and procedures for removal of interference have been described. The proposed method was applied successfully to the determination of sulfide in tap and wastewater samples

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE

OpenAIRE

Sanchi Nenkova; Peter Velev; Mirela Dragnevska; Diyana Nikolova; Kiril Dimitrov

2011-01-01

Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of co...

Comparison of endoscopy and barium swallow with marshmallow in dysphagia.

Science.gov (United States)

Somers, S; Stevenson, G W; Thompson, G

1986-06-01

Forty-four patients with dysphagia were examined both by endoscopy and by barium swallow with a marshmallow bolus. In these patients 36 stenoses were found: 34 by radiology and 30 by endoscopy. The radiologic criteria for stenosis included arrest of the marshmallow in a manner to support a column of barium and reproduction of the patient's symptoms at the time this occurred. Radiologic false negative findings were partly due to an inability by patients to swallow an adequate marshmallow bolus; endoscopic failures were associated with small endoscopes and mild stenoses.

Barium Tagging from nEXO Using Resonance Ionization Spectroscopy

Science.gov (United States)

Twelker, K.; Kravitz, S.

nEXO is a 5-ton liquid enriched-xenon time projection chamber (TPC) to search for neutrinoless double-beta decay, designed to have the sensitivity to completely probe the inverted mass hierarchy of Majorana neutrinos. The detector will accommodate-as a background reduction technique-a system to recover and identify the barium decay product. This upgrade will allow a background-free measurement of neutrinoless double-beta decay and increase the half-life sensitivity of the experiment by at least one order of magnitude. Ongoing research and development includes a system to test barium extraction from liquid xenon using surface adsorption and Resonance Ionization Spectroscopy (RIS).

Determination of barium in surface and ground waters at Centro Experimental Aramar area

Energy Technology Data Exchange (ETDEWEB)

Matoso, Erika, E-mail: ematoso@hotmail.com [Centro Tecnologico da Marinha em Sao Paulo (CEA/CTMS), Ipero, SP (Brazil). Centro Experimental Aramar; Cadore, Solange, E-mail: cadore@iqm.unicamp.br [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Quimica. Departamento de Quimica Analica

2015-07-01

Barium can be found in waters up to 1 mg L{sup -1} and came from natural sources such as sedimentary rocks erosion rich in feldspar and barite. Also anthropogenic activities can release this element such as oil and gas industry, agricultural defensives, chemical industry and waste disposal. At high doses, barium can be harmful to human central nervous system and can also cause high blood pressure, heart problems, fatigue and anxiety. The water potability defined by Brazilian's Ministry of Healthy sets barium concentration up to 0.7 mg L{sup -1} and official regulation defines the same limit of this element to superficial waters (according CONAMA resolution 357/2005) and ground waters (Sao Paulo state regulation). In this work, barium was analyzed monthly in superficial waters from 4 different sampling locations, located in a ratio of 10-km-long from Centro Experimental Aramar (CEA) at Ipanema River, during one year, in order to evaluate the river in different conditions (seasons, temperature and rain period). The ground water was collected every six months. The analytical technique applied was ICP OES and the method conditions were optimized: wavelength, linearity, signal background ratio, detection and quantification limits. Data obtained in this work will contribute to evaluate the presence of barium at CEA region and nearby in order to compare it with current Brazilian regulations. (author)

Determination of barium in surface and ground waters at Centro Experimental Aramar area

International Nuclear Information System (INIS)

Matoso, Erika; Cadore, Solange

2015-01-01

Barium can be found in waters up to 1 mg L -1 and came from natural sources such as sedimentary rocks erosion rich in feldspar and barite. Also anthropogenic activities can release this element such as oil and gas industry, agricultural defensives, chemical industry and waste disposal. At high doses, barium can be harmful to human central nervous system and can also cause high blood pressure, heart problems, fatigue and anxiety. The water potability defined by Brazilian's Ministry of Healthy sets barium concentration up to 0.7 mg L -1 and official regulation defines the same limit of this element to superficial waters (according CONAMA resolution 357/2005) and ground waters (Sao Paulo state regulation). In this work, barium was analyzed monthly in superficial waters from 4 different sampling locations, located in a ratio of 10-km-long from Centro Experimental Aramar (CEA) at Ipanema River, during one year, in order to evaluate the river in different conditions (seasons, temperature and rain period). The ground water was collected every six months. The analytical technique applied was ICP OES and the method conditions were optimized: wavelength, linearity, signal background ratio, detection and quantification limits. Data obtained in this work will contribute to evaluate the presence of barium at CEA region and nearby in order to compare it with current Brazilian regulations. (author)

Effect of barium-coated halloysite nanotube addition on the cytocompatibility, mechanical and contrast properties of poly(methyl methacrylate cement

Directory of Open Access Journals (Sweden)

Jammalamadaka U

2017-06-01

Full Text Available Uday Jammalamadaka,1 Karthik Tappa,1 Jeffery A Weisman,1 James Connor Nicholson,2 David K Mills1,3 1Center for Biomedical Engineering and Rehabilitation Science, 2Nanosystems Engineering, 3The School of Biological Sciences, Louisiana Tech University, Ruston, LA, USA Abstract: Halloysite nanotubes (HNTs were investigated as a platform for tunable nanoparticle composition and enhanced opacity in poly(methyl methacrylate (PMMA bone cement. Halloysite has been widely used to increase the mechanical properties of various polymer matrices, in stark contrast to other fillers such as barium sulfate that provide opacity but also decrease mechanical strength. The present work describes a dry deposition method for successively fabricating barium sulfate nanoparticles onto the exterior surface of HNTs. A sintering process was used to coat the HNTs in barium sulfate. Barium sulfate-coated HNTs were then added to PMMA bone cement and the samples were tested for mechanical strength and tailored opacity correlated with the fabrication ratio and the amount of barium sulfate-coated HNTs added. The potential cytotoxic effect of barium-coated HNTs in PMMA cement was also tested on osteosarcoma cells. Barium-coated HNTs were found to be completely cytocompatible, and cell proliferation was not inhibited after exposure to the barium-coated HNTs embedded in PMMA cement. We demonstrate a simple method for the creation of barium-coated nanoparticles that imparted improved contrast and material properties to native PMMA. An easy and efficient method for coating clay nanotubes offers the potential for enhanced imaging by radiologists or orthopedic surgeons. Keywords: barium, bone cement, halloysite, imaging, PMMA, sintering

75 FR 20625 - Barium Chloride From China

Science.gov (United States)

2010-04-20

... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-149 (Third Review)] Barium Chloride From China AGENCY: United States International Trade Commission. ACTION: Revised schedule for the subject review. DATES: Effective Date: April 9, 2010. FOR FURTHER INFORMATION CONTACT: Amy Sherman (202-205-3289...

Rheological properties of potassium barium borate glasses

NARCIS (Netherlands)

Szwejda, K.A.; Vogel, D.L.; Stevels, J.M.

1973-01-01

Several series of potassium barium borate glasses have been investigated as to their rheological properties. It has been found, that all these glasses show deviations from ‘Newtonian’ behaviour below temperatures corresponding to viscosities of 1010 poises. The activation energies of viscous flow

Catalytic oxidation of sulfide in drinking water treatment: activated carbon as catalyst; Katalytische Oxidation von Sulfid bei der Trinkwasseraufbereitung: Aktivkohle als Katalysator

Energy Technology Data Exchange (ETDEWEB)

Hultsch, V; Grischek, T; Wolff, D; Worch, E [Technische Univ. Dresden (Germany). Inst. fuer Wasserchemie; Gun, J [Hebrew Univ. of Jerusalem (Israel). Div. of Environmental Sciences, Fredy and Nadine Herrmann School of Applied Science

2001-07-01

In regions with warm climate and limited water resources high sulfide concentrations in groundwater can cause problems during drinking water treatment. Aeration of the raw water is not always sufficient to ensure the hydrogen sulfide concentration below the odour threshold value for hydrogen sulfide. As an alternative, activated carbon can be used as a catalyst for sulfide oxidation of raw water. The use of different types of activated carbon was investigated in kinetic experiments. Both Catalytic Carbon from Calgon Carbon and granulated activated carbon from Norit showed high catalytic activities. The results of the experiments are discussed with regard to the practical use of activated carbon for the elimination of hydrogen sulfide during drinking water treatment. (orig.)

Barium swallow study in routine clinical practice: a prospective study in patients with chronic cough.

Science.gov (United States)

Nin, Carlos Shuler; Marchiori, Edson; Irion, Klaus Loureiro; Paludo, Artur de Oliveira; Alves, Giordano Rafael Tronco; Hochhegger, Daniela Reis; Hochhegger, Bruno

2013-01-01

To assess the routine use of barium swallow study in patients with chronic cough. Between October of 2011 and March of 2012, 95 consecutive patients submitted to chest X-ray due to chronic cough (duration > 8 weeks) were included in the study. For study purposes, additional images were obtained immediately after the oral administration of 5 mL of a 5% barium sulfate suspension. Two radiologists systematically evaluated all of the images in order to identify any pathological changes. Fisher's exact test and the chi-square test for categorical data were used in the comparisons. The images taken immediately after barium swallow revealed significant pathological conditions that were potentially related to chronic cough in 12 (12.6%) of the 95 patients. These conditions, which included diaphragmatic hiatal hernia, esophageal neoplasm, achalasia, esophageal diverticulum, and abnormal esophageal dilatation, were not detected on the images taken without contrast. After appropriate treatment, the symptoms disappeared in 11 (91.6%) of the patients, whereas the treatment was ineffective in 1 (8.4%). We observed no complications related to barium swallow, such as contrast aspiration. Barium swallow improved the detection of significant radiographic findings related to chronic cough in 11.5% of patients. These initial findings suggest that the routine use of barium swallow can significantly increase the sensitivity of chest X-rays in the detection of chronic cough-related etiologies.

Investigation on the effects of milling atmosphere on synthesis of barium ferrite/magnetite nanocomposite

NARCIS (Netherlands)

Molaei, M.J.; Ataie, A.; Raygan, S.; Picken, S.J.

2011-01-01

In this research, barium ferrite /magnetite nanocomposites synthesized via a mechano-chemical route. Graphite was used in order to reduce hematite content of barium ferrite to magnetite to produce a magnetic nanocomposite. The effects of processing conditions on the powder characteristics were

A Reaction Involving Oxygen and Metal Sulfides.

Science.gov (United States)

Hill, William D. Jr.

1986-01-01

Describes a procedure for oxygen generation by thermal decomposition of potassium chlorate in presence of manganese dioxide, reacted with various sulfides. Provides a table of sample product yields for various sulfides. (JM)

Edge detection of barium-filled stomach picture by one-dimensional collation method

International Nuclear Information System (INIS)

Nakamura, Shizuo

1983-01-01

The method for the contour edge detection of barium- filled stomach pictures by X-ray for the automatic screening is described using computer technique. It is necessary for the automatic screening of barium- filling pictures to detect accurately the outline of stomachs because the analysis of repletion pictures is performed by checking the disorder of marginal contours and abnormal stomach shapes. However, the detection of the coutour lines is difficult to be successful for the reason that the contrast of stomach pictures to background is low, a stomach is not necessarily filled completely with barium and the shadow of barium flowing into intestines is superimposed on stomach images and the shading is likely to occur. The engineering processing against these problems is not yet solved. In order to reduce the noise due to differential operator, the proposed method determines the boundary of a thing generally by the threshold value of density, and defines the edge of the thing from the differential waveform of density in the vicinity of the boundary. In addition, the method corrects the detection error caused by the local nonconformity of parameters by comparing the edges between the adjacent lines. As a result, in spite of its simple algorithm, the edges with good continuity and less noise can be detected, and the method is not much affected by shading. This method was found to be applicable to the images of others than stomachs. The extraction of the contour of barium- filling pictures requires the high level recognition processing instead of the simple conditioning. (Wakatsuki, Y.)

Observation of a barium xenon exciplex within a large argon cluster.

Science.gov (United States)

Briant, M; Gaveau, M-A; Mestdagh, J-M

2010-07-21

Spectroscopic measurements provide fluorescence and excitation spectra of a single barium atom codeposited with xenon atoms on argon clusters of average size approximately 2000. The spectra are studied as a function of the number of xenon atoms per cluster. The excitation spectrum with approximately 10 xenon atoms per cluster is qualitatively similar to that observed when no xenon atom is present on the cluster. It consists of two bands located on each side of the 6s6p (1)P-6s(2) (1)S resonance line of the free barium. In contrast, the fluorescence spectrum differs qualitatively since a barium-xenon exciplex is observed, which has no counterpart in xenon free clusters. In particular an emission is observed, which is redshifted by 729 cm(-1) with respect to the Ba(6s6p (1)P-6s(2) (1)S) resonance line.

Azo dye decolorization assisted by chemical and biogenic sulfide

Energy Technology Data Exchange (ETDEWEB)

Prato-Garcia, Dorian [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico); Cervantes, Francisco J. [División de Ciencias Ambientales, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la Presa de San José 2055, San Luis Potosí 78216 (Mexico); Buitrón, Germán, E-mail: gbuitronm@ii.unam.mx [Laboratory for Research on Advanced Processes for Water Treatment, Unidad Académica Juriquilla, Instituto de Ingeniería, Universidad Nacional Autónoma de México, Blvd. Juriquilla 3001, Querétaro 76230 (Mexico)

2013-04-15

Highlights: ► Azo dyes were reduced efficiently by chemical and biogenic sulfide. ► Biogenic sulfide was more efficient than chemical sulfide. ► There was no competition between dyes and sulfate for reducing equivalents. ► Aromatic amines barely affected the sulfate-reducing process. -- Abstract: The effectiveness of chemical and biogenic sulfide in decolorizing three sulfonated azo dyes and the robustness of a sulfate-reducing process for simultaneous decolorization and sulfate removal were evaluated. The results demonstrated that decolorization of azo dyes assisted by chemical sulfide and anthraquinone-2,6-disulfonate (AQDS) was effective. In the absence of AQDS, biogenic sulfide was more efficient than chemical sulfide for decolorizing the azo dyes. The performance of sulfate-reducing bacteria in attached-growth sequencing batch reactors suggested the absence of competition between the studied azo dyes and the sulfate-reducing process for the reducing equivalents. Additionally, the presence of chemical reduction by-products had an almost negligible effect on the sulfate removal rate, which was nearly constant (94%) after azo dye injection.

Simultaneous removal of sulfide, nitrate and acetate: Kinetic modeling

Energy Technology Data Exchange (ETDEWEB)

Wang Aijie, E-mail: waj0578@hit.edu.cn [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China); Liu Chunshuang; Ren Nanqi; Han Hongjun [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China); Lee Duujong [State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (SKLUWRE, HIT), Harbin 150090 (China); Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)

2010-06-15

Biological removal of sulfide, nitrate and chemical oxygen demand (COD) simultaneously from industrial wastewaters to elementary sulfur (S{sup 0}), N{sub 2}, and CO{sub 2}, or named the denitrifying sulfide (DSR) process, is a cost effective and environmentally friendly treatment process for high strength sulfide and nitrate laden organic wastewater. Kinetic model for the DSR process was established for the first time on the basis of Activated Sludge Model No. 1 (ASM1). The DSR experiments were conducted at influent sulfide concentrations of 200-800 mg/L, whose results calibrate the model parameters. The model correlates well with the DSR process dynamics. By introducing the switch function and the inhibition function, the competition between autotrophic and heterotrophic denitrifiers is quantitatively described and the degree of inhibition of sulfide on heterotrophic denitrifiers is realized. The model output indicates that the DSR reactor can work well at 0.5 < C/S < 3.0 with influent sulfide concentration of 400-1000 mg/L. At >1000 mg/L influent sulfide, however, the DSR system will break down.

Correlation between Timed Barium Esophagogram and the Eckardt Stage in Achalasia

Directory of Open Access Journals (Sweden)

Waraporn Boonsomjint, M.D.

2018-01-01

Full Text Available Objective: To evaluate the correlation of timed barium esophagogram (TBE parameters and the Eckardt stage in patients with achalasia. Methods: This prospective study was done in 29 adult achalasia patients who underwent TBE and were assessed for clinical symptoms according to the Eckardt stage. The association between the Eckardt stage and TBE parameters including the height and the width of barium column, esophageal emptying between 1 and 5 minutes, which was calculated by comparing the area of barium column and esophageal emptying between 0 and 5 minutes, which was calculated from the relative changes in ingested volume to estimated volume of barium column on the 5-min image and this was calculated by using Kruskal-Wallis test. Comparison of mean emptied volume at 1 min. image and mean emptied volume between 1 and 5 minutes was done by using paired samples t-tests. Results: There was a significant difference in the amount of emptied volume at 1 min image (mean = 118.27, SD = 31.1 and emptied volume between 1 min and 5 min images (mean = 11.41, SD = 9.4; t(27 =15.375, p < 0.001. Statistically significant difference in esophageal emptying between 1 and 5 minutes across the Eckardt stages was found (H=8.115, 3 d.f., p=0.044. The difference was statistically significant between the Eckardt stage 2 and 3 (p=0.039. There were no statistically significant differences in other TBE parameters across the Eckardt stages. Conclusion: No statistically significant difference in TBE parameters across the Eckardt stages was found in the present study. However, TBE is a useful objective method to assess esophageal emptying in patients with achalasia. Interpretation of TBE should be standardized. Calculation of esophageal emptying should include the amount of barium emptied from the esophagus in the first minute.

Use of sulfide-containing liquors for removing mercury from flue gases

Science.gov (United States)

Nolan, Paul S.; Downs, William; Bailey, Ralph T.; Vecci, Stanley J.

2006-05-02

A method and apparatus for reducing and removing mercury in industrial gases, such as a flue gas, produced by the combustion of fossil fuels, such as coal, adds sulfide ions to the flue gas as it passes through a scrubber. Ideally, the source of these sulfide ions may include at least one of: sulfidic waste water, kraft caustic liquor, kraft carbonate liquor, potassium sulfide, sodium sulfide, and thioacetamide. The sulfide ion source is introduced into the scrubbing liquor as an aqueous sulfide species. The scrubber may be either a wet or dry scrubber for flue gas desulfurization systems.

The effect of barium temperature on esophageal and castric motility in dogs: a fluoroscopic study

International Nuclear Information System (INIS)

Eville, P.; Ackerman, N.

1984-01-01

The influence of barium temperature on canine esophageal transit time and gastric motility were studied fluoroscopically. Micropulverized barium sulfate (30% wt/vol) at 35°F, 70°F, and 100°F was given orally to each of five dogs with a minimum of two hours between each temperature. Esophageal transit times ranged from 4 to 9.67 seconds, and gastric contractions average four per minute. Barium temperature had no significant effect on either esophageal transit time or gastric motility

Colonic transit time in patient with slow-transit constipation: Comparison of radiopaque markers and barium suspension method

International Nuclear Information System (INIS)

Xu Huimin; Han Jiagang; Na Ying; Zhao Bo; Ma Huachong; Wang Zhenjun

2011-01-01

Background: Colonic transit study provides valuable information before surgical treatment is considered for patient with constipation. The radiopaque markers method is the most common way for evaluating colon transit time. The aim of this study is to compare the barium suspension with the radiopaque makers to assess the colonic mobility in patient with constipation. Methods: Colonic transit time was measured in 11 female patients with slow-transit constipation using both radiopaque markers and barium suspension method. In radiopaque markers method, the patient ingested 20 markers on the first day, and an abdominal radiograph was performed every 24 h until 80% markers were excreted. In barium suspension method, the patient swallowed up to 50 ml of 200% (w/v) barium meal. The abdominal radiographs were taken at the same time point as the former. Results: The total or segmental colonic transit time were obviously prolonged in all patients. Segmental transits time spent in the right colon, left colon and rectosigmoid for radiopaque markers and barium suspension method was, respectively, 30 ± 6 h and 34 ± 7 h; 38 ± 9 h and 32 ± 6 h; 40 ± 8 h and 38 ± 10 h. In the radiopaque markers method, total colonic transit time was 108 ± 14 h and it was 103 ± 13 h in the barium suspension method (P > 0.05). Conclusion: The barium suspension and radiopaque markers gave the similar results for colonic transit time. The barium suspension was a simple and cheap method for evaluating the colonic mobility.

Barium diffusion in metallo-organic solution deposited barrier layers and Y1Ba2Cu3O7-x films

International Nuclear Information System (INIS)

Lipeles, R.A.; Leung, M.S.; Thiede, D.A.

1990-01-01

This paper reports on barium silicate and barium aluminate films that were studied for use as chemical reaction and diffusion barrier layers for Y 1 Ba 2 Cu 3 O 7-x (YBC) deposited on sapphire and fused silica substrates by the sol-gel technique. Depth profiling by secondary ion mass spectrometry (SIMS) was used to characterize the abruptness of the interfaces between the barrier layer and the YBC film as well as the barrier layer and the substrate. The authors found that barium aluminate films reacted with fused silica substrates forming a coarse-grained barium silicate phase. Barium silicate, BaSiO 3 , also reacted with silica substrates forming a broad, amorphous reaction zone containing some BaSi 2 O 5 . Although barium silicate and barium aluminate deposited on sapphire formed a BaAl 12 O 19 phase, they provided a barrier to barium diffusion from sol-gel deposited YBC. Crystalline barium aluminate grown on c-cut sapphire was the most effective barrier layer for the growth of YBC films; compositionally uniform YBC films were made similar to that grown on strontium titanate substrates. These data show that chemically stable, crystalline films are more effective barrier layers than amorphous films

Thermoelectric properties of non-stoichiometric lanthanum sulfides

International Nuclear Information System (INIS)

Shapiro, E.; Danielson, L.R.

1983-01-01

The lanthanum sulfides are promising candidate materials for high-efficiency thermoelectric applications at temperatures up to 1300 0 C. The nonstoichiometric lanthanum sulfides (LaS /SUB x/ , where 1.33 2 //rho/ can be chosen. The thermal conductivity remains approximately constant with stoichiometry, so a material with an optimum value of α 2 //rho/ should possess the optimum figure-of-merit. Data for the Seebeck coefficient and electrical resistivity of non-stoichiometric lanthanum sulfides is presented, together with structural properties of these materials

High temperature impedance spectroscopy of barium stannate ...

Indian Academy of Sciences (India)

(M = Ba, Sr, Ca and Pb). ... Barium stannate (BaSnO3) is a cubic pervoskite oxide com- .... were gold-sputtered and scanned in different regions using .... de ions. Water insertion into the oxide structure can be re- presented as the process of ...

Improved thermal stability and wettability behavior of thermoplastic polyurethane / barium metaborate composites

International Nuclear Information System (INIS)

Baştürka, Emre; Madakbaş, Seyfullah; Kahraman, Memet Vezir

2016-01-01

In this paper, it was targeted to the enhance thermal stability and wettability behavior of thermoplastic polyurethane (TPU) by adding barium metaborate. TPU-Barium metaborate composites were prepared by adding various proportions of barium metaborate to TPU. The chemical structures of the composites were characterised by fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. All prepared composites have extremely high Tg and thermal stability as determined from DSC and TGA analysis. All composite materials have the Tg ranging from 15 to 35 °C. The surface morphologies of the composites were investigated by a scanning electron microscopy. Mechanical properties of the samples were characterized with stress-strain test. Hydrophobicity of the samples was determined by the contact angle measurements. The obtained results proved that thermal, hydrophobic and mechanical properties were improved. (author)

Improved thermal stability and wettability behavior of thermoplastic polyurethane / barium metaborate composites

Energy Technology Data Exchange (ETDEWEB)

Baştürka, Emre; Madakbaş, Seyfullah; Kahraman, Memet Vezir, E-mail: smadakbas@marmara.edu.tr [Department of Chemistry, Marmara University, Istanbul (Turkey)

2016-03-15

In this paper, it was targeted to the enhance thermal stability and wettability behavior of thermoplastic polyurethane (TPU) by adding barium metaborate. TPU-Barium metaborate composites were prepared by adding various proportions of barium metaborate to TPU. The chemical structures of the composites were characterised by fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. All prepared composites have extremely high Tg and thermal stability as determined from DSC and TGA analysis. All composite materials have the Tg ranging from 15 to 35 °C. The surface morphologies of the composites were investigated by a scanning electron microscopy. Mechanical properties of the samples were characterized with stress-strain test. Hydrophobicity of the samples was determined by the contact angle measurements. The obtained results proved that thermal, hydrophobic and mechanical properties were improved. (author)

Deposition barium titanate (BaTiO3) doped lanthanum with chemical solution deposition

International Nuclear Information System (INIS)

Iriani, Y.; Nurhadi, N.; Jamaludin, A.

2016-01-01

Deposition of Barium Titanate (BaTiO 3 ) thin films used Chemical Solution Deposition (CSD) method and prepared with spin coater. BaTiO 3 is doped with lanthanum, 1%, 2%, and 3%. The thermal process use annealing temperature 900°C and holding time for 3 hours. The result of characterization with x-ray diffraction (XRD) equipment show that the addition of La 3+ doped on Barium Titanate caused the change of angle diffraction.The result of refine with GSAS software shows that lanthanum have been included in the structure of BaTiO 3 . Increasing mol dopant La 3+ cause lattice parameter and crystal volume become smaller. Characterization result using Scanning Electron Microscopy (SEM) equipment show that grain size (grain size) become smaller with increasing mole dopant (x) La 3+ . The result of characterization using Sawyer Tower methods show that all the samples (Barium Titanante and Barium Titanate doped lanthanum) are ferroelectric material. Increasing of mole dopant La 3+ cause smaller coercive field and remanent polarization increases. (paper)

Indentation plasticity of barium titanate single crystals: Dislocation influence on ferroelectric domain walls

International Nuclear Information System (INIS)

Liu, D.; Chelf, M.; White, K.W.

2006-01-01

The plastic behaviors of barium titanate (001) and (110) single crystals are studied with atomic force microscopy and piezoresponse force microscopy (PFM) following nanoindendation damage. Plastic deformation mechanisms of ferroelectric barium titanate single crystals are discussed with a focus on the interaction between PFM response and dislocation activities. Nanoindentation tests indicate that the theoretical strength is approached prior to the first pop-in event, consistent with the creation of dislocation nucleation sites required for the onset of plasticity. Surface topographic and piezoelectric analyses indicate that pile-ups around indents result from dislocation activities on the primary slip system, {110} pc pc . The more complex indentation-induced domain patterns observed on (110) barium titanate are also discussed

Fabrication and electrical characterization of 15% yttrium-doped barium zirconate-nitrate freeze drying method combined with vacuum heating

International Nuclear Information System (INIS)

Imashuku, Susumu; Uda, Tetsuya; Nose, Yoshitaro; Awakura, Yasuhiro

2011-01-01

Research highlights: → Very fine 15% yttrium-doped barium zirconate powder of particle size about 30 nm was obtained by synthesizing at 500 deg. C in vacuum from powder mixed by the nitrate freeze-drying method. → Large and homogeneous grains of 15% yttrium-doped barium zirconate were easily obtained using the synthesized powder. → Grain boundary resistance was not inversely proportional to the grain size as theoretically expected. → Specific grain boundary conductivity varies with samples because impurities and/or evaporation loss of barium oxide might affect the grain-boundary resistance in 15% yttrium-doped barium zirconate. - Abstract: We applied a nitrate freeze-drying method to obtain a fine synthesized powder of 15% yttrium-doped barium zirconate. Fine 15% yttrium-doped barium zirconate powder of particle size about 30 nm was obtained by synthesizing at 500 deg. C in vacuum from a powder mixed by the nitrate freeze-drying method. However, we could not obtain such fine powder by synthesizing in air. Using the powder synthesized in vacuum, large and homogeneous grains of 15% yttrium-doped barium zirconate were easily obtained after sintering. Then, the bulk and grain boundary resistance were evaluated by AC 2-terminal measurement of sample in the form of bar and pellet and DC 4-terminal measurement of bar-shape sample. The grain boundary resistance was not inversely proportional to the grain size as theoretically expected. We concluded that specific grain boundary conductivity varies with samples. Some impurities, evaporation loss of barium oxide and/or other unexpected reasons might affect the grain boundary resistance in 15% yttrium-doped barium zirconate.

Barium isotopes in Allende meteorite - Evidence against an extinct superheavy element

Science.gov (United States)

Lewis, R. S.; Anders, E.; Shimamura, T.; Lugmair, G. W.

1983-01-01

Carbon and chromite fractions from the Allende meteorite that contain isotopically anomalous xenon-131 to xenon-136 (carbonaceous chondrite fission or CCF xenon) at up to 5 x 10 to the 11th atoms per gram show no detectable isotopic anomalies in barium-130 to barium-138. This rules out the possibility that the CCF xenon was formed by in situ fission of an extinct superheavy element. Apparently the CCF xenon and its carbonaceous carrier are relics from stellar nucleosynthesis.

Comparison of Carbon XANES Spectra from an Iron Sulfide from Comet Wild 2 with an Iron Sulfide Interplanetary Dust Particle

Science.gov (United States)

Wirick, S.; Flynn, G. J.; Keller, L. P.; Sanford, S. A.; Zolensky, M. E.; Messenger, Nakamura K.; Jacobsen, C.

2008-01-01

Among one of the first particles removed from the aerogel collector from the Stardust sample return mission was an approx. 5 micron sized iron sulfide. The majority of the spectra from 5 different sections of this particle suggests the presence of aliphatic compounds. Due to the heat of capture in the aerogel we initially assumed these aliphatic compounds were not cometary but after comparing these results to a heated iron sulfide interplanetary dust particle (IDP) we believe our initial interpretation of these spectra was not correct. It has been suggested that ice coating on iron sulfides leads to aqueous alteration in IDP clusters which can then lead to the formation of complex organic compounds from unprocessed organics in the IDPs similar to unprocessed organics found in comets [1]. Iron sulfides have been demonstrated to not only transform halogenated aliphatic hydrocarbons but also enhance the bonding of rubber to steel [2,3]. Bromfield and Coville (1997) demonstrated using Xray photoelectron spectroscopy that "the surface enhancement of segregated sulfur to the surface of sulfided precipitated iron catalysts facilitates the formation of a low-dimensional structure of extraordinary properties" [4]. It may be that the iron sulfide acts in some way to protect aliphatic compounds from alteration due to heat.

75 FR 19657 - Barium Chloride From China

Science.gov (United States)

2010-04-15

... China AGENCY: United States International Trade Commission. ACTION: Notice of Commission determination... China. SUMMARY: The Commission hereby gives notice that it will proceed with a full review pursuant to... antidumping duty order on barium chloride from China would be likely to lead to continuation or recurrence of...

Esophageal intramural pseudodiverticulosis characterized by barium esophagography: a case report

LENUS (Irish Health Repository)

O'Connor, Owen J

2010-05-21

Abstract Introduction Esophageal intramural pseudodiverticulosis is a rare condition characterized by the dilatation of the submucosal glands. Case presentation We present a case of esophageal intramural pseudodiverticulosis in a 72-year-old Caucasian man who presented with dysphagia and with a background history of alcohol abuse. An upper gastrointestinal endoscopy of our patient showed an esophageal stricture with abnormal mucosal appearances, but no malignant cells were seen at biopsy. Appearances on a barium esophagram were pathognomonic for esophageal intramural pseudodiverticulosis. Conclusion We demonstrate the enduring usefulness of barium esophagography in the characterization of abnormal mucosal appearances at endoscopy.

Barium swallow study in routine clinical practice: a prospective study in patients with chronic cough

Directory of Open Access Journals (Sweden)

Carlos Shuler Nin

2013-12-01

Full Text Available OBJECTIVE: To assess the routine use of barium swallow study in patients with chronic cough.METHODS: Between October of 2011 and March of 2012, 95 consecutive patients submitted to chest X-ray due to chronic cough (duration > 8 weeks were included in the study. For study purposes, additional images were obtained immediately after the oral administration of 5 mL of a 5% barium sulfate suspension. Two radiologists systematically evaluated all of the images in order to identify any pathological changes. Fisher's exact test and the chi-square test for categorical data were used in the comparisons.RESULTS: The images taken immediately after barium swallow revealed significant pathological conditions that were potentially related to chronic cough in 12 (12.6% of the 95 patients. These conditions, which included diaphragmatic hiatal hernia, esophageal neoplasm, achalasia, esophageal diverticulum, and abnormal esophageal dilatation, were not detected on the images taken without contrast. After appropriate treatment, the symptoms disappeared in 11 (91.6% of the patients, whereas the treatment was ineffective in 1 (8.4%. We observed no complications related to barium swallow, such as contrast aspiration.CONCLUSIONS: Barium swallow improved the detection of significant radiographic findings related to chronic cough in 11.5% of patients. These initial findings suggest that the routine use of barium swallow can significantly increase the sensitivity of chest X-rays in the detection of chronic cough-related etiologies.

Simultaneous removal of sulfide, nitrate and acetate: Kinetic modeling

International Nuclear Information System (INIS)

Wang Aijie; Liu Chunshuang; Ren Nanqi; Han Hongjun; Lee Duujong

2010-01-01

Biological removal of sulfide, nitrate and chemical oxygen demand (COD) simultaneously from industrial wastewaters to elementary sulfur (S 0 ), N 2 , and CO 2 , or named the denitrifying sulfide (DSR) process, is a cost effective and environmentally friendly treatment process for high strength sulfide and nitrate laden organic wastewater. Kinetic model for the DSR process was established for the first time on the basis of Activated Sludge Model No. 1 (ASM1). The DSR experiments were conducted at influent sulfide concentrations of 200-800 mg/L, whose results calibrate the model parameters. The model correlates well with the DSR process dynamics. By introducing the switch function and the inhibition function, the competition between autotrophic and heterotrophic denitrifiers is quantitatively described and the degree of inhibition of sulfide on heterotrophic denitrifiers is realized. The model output indicates that the DSR reactor can work well at 0.5 1000 mg/L influent sulfide, however, the DSR system will break down.

Hydrogen sulfide oxidation without oxygen - oxidation products and pathways

International Nuclear Information System (INIS)

Fossing, H.

1992-01-01

Hydrogen sulfide oxidation was studied in anoxic marine sediments-both in undisturbed sediment cores and in sediment slurries. The turn over of hydrogen sulfide was followed using 35 S-radiolabeled hydrogen sulfide which was injected into the sediment. However, isotope exchange reactions between the reduced sulfur compounds, in particular between elemental sulfur and hydrogen sulfide, influenced on the specific radioactivity of these pools. It was, therefore, not possible to measure the turn over rates of the reduced sulfur pools by the radiotracer technique but merely to use the radioisotope to demonstrate some of the oxidation products. Thiosulfate was one important intermediate in the anoxic oxidation of hydrogen sulfide and was continuously turned over by reduction, oxidation and disproportionation. The author discusses the importance of isotope exchange and also presents the results from experiments in which both 35 S-radiolabeled elemental sulfur, radiolabeled hydrogen sulfide and radiolabeled thiosulfate were used to study the intermediates in the oxidative pathways of the sulfur cycle

Evidence against barium in the mushroom Trogia venenata as a cause of sudden unexpected deaths in Yunnan, China.

Science.gov (United States)

Zhang, Ying; Li, Yanchun; Wu, Gang; Feng, Bang; Yoell, Shanze; Yu, Zefen; Zhang, Keqin; Xu, Jianping

2012-12-01

This study examined barium concentrations in the mushroom Trogia venenata, the leading culprit for sudden unexpected deaths in Yunnan, southwest China. We found that barium concentrations in T. venenata from Yunnan were low and comparable to other foods, inconsistent with barium concentrations in this mushroom as a significant contributor to these deaths.

Barium borate nanorod decorated reduced graphene oxide for optical power limiting applications

Science.gov (United States)

Muruganandi, G.; Saravanan, M.; Vinitha, G.; Jessie Raj, M. B.; Sabari Girisun, T. C.

2018-01-01

By simple hydrothermal method, nanorods of barium boate were successfully loaded on reduced graphene oxide sheets. Powder XRD confirms the incorporation of barium borate (2θ = 29°, (202)) along with the transition of graphene oxide (2θ = 12°, (001)) into reduced graphene oxide (2θ = 25°, (002)). In the FTIR spectra, presence of characteristic absorption peaks of rGO (1572 and 2928 cm-1) and barium borate (510, 760 and 856 cm-1) further evidences the formation of BBO:rGO nanocomposite. FESEM images potray the existence of graphene sheets as thin layers and growth of barium borate as nanorods on the sheets of reduced graphene oxide. Ground state absorption studies reveal the hypsochromic shift in the absorption maxima of the graphene layers due to reduction of graphene oxide and hypochromic shift in the absorbance intensity due to the inclusion of highly transparent barium bortae. The photoluminescence of BBO:rGO shows maximum emission in the UV region arising from the direct transitions involving the valence band and conduction band in the band gap region. Z-scan technique using CW diode pumped Nd:YAG laser (532 nm, 50 mW) exposes that both nanocomposite and individual counterpart possess saturable absorption and self-defocusing behavior. Third-order nonlinear optical coefficients of BBO:rGO nanocomposite is found to be higher than bare graphene oxide. In particular the nonlinear refractive index of nanocomposite is almost four times higher than GO which resulted in superior optical power limiting action. Strong nonlinear refraction (self-defocusing) and lower onset limiting thershold makes the BBO:rGO nanocomposite preferable candidate for laser safety devices.

Granulomatous colitis: findings on double contrast barium enema and follow-up studies

International Nuclear Information System (INIS)

Song, Jong Gi; Han, Joon Koo; Kim, Seung Hoon; Choo, Sung Wook; Kim, Seung Cheol; Choi, Byung Ihn

1995-01-01

To evaluate the radiologic findings of granulomatous colitis on double contrast barium enema and changes on follow-up studies. Serial double contrast barium enema of six patients with granulomatous colitis confirmed by endoscopic biopsy were reviewed. We analyzed the radiologic findings and their follow-up changes, including aphthous ulcers, lymphoid hyperplasia, deep ulcers, cobble stone appearance, geographic ulcers, asymmetric involvement of ulcers, skip lesions, sinus tract, fistula formation, pseudosacculation, focal stricture, and small bowel involvement. Pretreatment double contrast barium enema findings were aphthous ulcers in five patients, deep ulcer in six, cobble stone appearance in five, longitudinal geographic ulcers in two, fistulas in one, pseudosacculations in two, focal stricture in one, and pseudopolyps in six. Also, anal ulcers were observed in two patients, asymmetric involvement of ulcers in three, skip lesions in four, and small bowel involvement in five in five patients proved to have inactive disease after treatment, aphthous ulcers and deep ulcers disappeared. Geographic ulcers of two patients and anal ulcer of one patients decreased in size or depth. Pseudosacculation in one patient disappeared. Pseudopolyps decreased in two patients, increased in one, and decreased after increase in two. One patient whose disease remained active after treatment showed maintenance or increase of ulcers or fistula. And their pseudosacculation or focal stricture unchanged and pseudopolyps decreased. The major radiologic findings of chronic granulomatous colitis on double contrast barium enema are aphthous ulcer, deep ulcer, cobble stone appearance, discontinuity of the lesion and coexistence of ulcers and pseudopolyps. And, double contrast barium enema is good follow-up modality because its findings correlate with clinical course of the granulomatous colitis after treatment

Trace metal distribution and mobility in drill cuttings and produced waters from Marcellus Shale gas extraction: Uranium, arsenic, barium

International Nuclear Information System (INIS)

Phan, Thai T.; Capo, Rosemary C.; Stewart, Brian W.; Graney, Joseph R.; Johnson, Jason D.; Sharma, Shikha; Toro, Jaime

2015-01-01

Highlights: • Distributions of U, As, and Ba in Marcellus Shale were determined. • As is primarily associated with sulfide minerals, Ba with exchange sites. • Most U is in the silicate minerals, but up to 20% is partitioned into carbonate. • Low [U] and [As] in produced water are consistent with reducing downhole conditions. • Proper waste management should account for potential mobilization of U and As. - Abstract: Development of unconventional shale gas wells can generate significant quantities of drilling waste, including trace metal-rich black shale from the lateral portion of the drillhole. We carried out sequential extractions on 15 samples of dry-drilled cuttings and core material from the gas-producing Middle Devonian Marcellus Shale and surrounding units to identify the host phases and evaluate the mobility of selected trace elements during cuttings disposal. Maximum whole rock concentrations of uranium (U), arsenic (As), and barium (Ba) were 47, 90, and 3333 mg kg −1 , respectively. Sequential chemical extractions suggest that although silicate minerals are the primary host for U, as much as 20% can be present in carbonate minerals. Up to 74% of the Ba in shale was extracted from exchangeable sites in the shale, while As is primarily associated with organic matter and sulfide minerals that could be mobilized by oxidation. For comparison, U and As concentrations were also measured in 43 produced water samples returned from Marcellus Shale gas wells. Low U concentrations in produced water (<0.084–3.26 μg L −1 ) are consistent with low-oxygen conditions in the wellbore, in which U would be in its reduced, immobile form. Arsenic was below detection in all produced water samples, which is also consistent with reducing conditions in the wellbore minimizing oxidation of As-bearing sulfide minerals. Geochemical modeling to determine mobility under surface storage and disposal conditions indicates that oxidation and/or dissolution of U

A surface-chemistry study of barium ferrite nanoplates with DBSa-modified surfaces

Energy Technology Data Exchange (ETDEWEB)

Lisjak, Darja, E-mail: darja.lisjak@ijs.si [Jožef Stefan Institute, Ljubljana (Slovenia); Ovtar, Simona; Kovač, Janez [Jožef Stefan Institute, Ljubljana (Slovenia); Gregoratti, Luca; Aleman, Belen; Amati, Matteo [Elettra – Sincrotrone Trieste S.C.p.A. di interesse nazionale, Trieste (Italy); Fanetti, Mattia [University of Nova Gorica, Nova Gorica (Slovenia); Istituto Officina dei Materiali CNR, Area Science Park, Trieste (Italy); Makovec, Darko [Jožef Stefan Institute, Ljubljana (Slovenia)

2014-06-01

Barium ferrite (BaFe{sub 12}O{sub 19}) is a ferrimagnetic oxide with a high magnetocrystalline anisotropy that can be exploited in magnetically aligned ceramics or films for self-biased magnetic applications. Magnetic alignment of the films can be achieved by the directed assembly of barium ferrite nanoplates. In this investigation the nanoplates were synthesized hydrothermally and suspended in 1-butanol using dodecylbenzene sulphonic acid (DBSa) as a surfactant. They were then deposited in an electric or magnetic field on flat substrates and exhibited a significant preferential alignment in the plane of the substrate, allowing a differentiation between the analysis of their basal and side planes using scanning photoelectron microscopy with a lateral resolution down to 100 nm. The surface chemistry of the nanoplates was additionally studied with X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. For a comparison, bare barium ferrite nanoplates were also analyzed after decomposing the DBSa at 460 °C. The deviation of the surface chemistry from the stoichiometric composition was observed and the adsorption of the DBSa molecules on the nanoplates was confirmed with all three methods. Different types of bonding (physi- or chemisorption) were possible and considered with respect to the assembly of the barium ferrite nanoplates into anisotropic magnetic films.

Individual-specific transgenerational marking of fish populations based on a barium dual-isotope procedure.

Science.gov (United States)

Huelga-Suarez, Gonzalo; Moldovan, Mariella; Garcia-Valiente, America; Garcia-Vazquez, Eva; Alonso, J Ignacio Garcia

2012-01-03

The present study focuses on the development and evaluation of an individual-specific transgenerational marking procedure using two enriched barium isotopes, (135)Ba and (137)Ba, mixed at a given and selectable molar ratio. The method is based on the deconvolution of the isotope patterns found in the sample into four molar contribution factors: natural xenon (Xe nat), natural barium (Ba nat), Ba135, and Ba137. The ratio of molar contributions between Ba137 and Ba135 is constant and independent of the contribution of natural barium in the sample. This procedure was tested in brown trout ( Salmo trutta ) kept in captivity. Trout were injected with three different Ba137/Ba135 isotopic signatures ca. 7 months and 7 days before spawning to compare the efficiency of the marking procedure at long and short term, respectively. The barium isotopic profiles were measured in the offspring by means of inductively coupled plasma mass spectrometry. Each of the three different isotopic signatures was unequivocally identified in the offspring in both whole eggs and larvae. For 9 month old offspring, the characteristic barium isotope signatures could also be detected in the otoliths even in the presence of a high and variable amount of barium of natural isotope abundance. In conclusion, it can be stated that the proposed dual-isotope marking is inheritable and can be detected after both long-term and short-term marking. Furthermore, the dual-isotope marking can be made individual-specific, so that it allows identification of offspring from a single individual or a group of individuals within a given fish group. © 2011 American Chemical Society

Reduction of produced elementary sulfur in denitrifying sulfide removal process.

Science.gov (United States)

Zhou, Xu; Liu, Lihong; Chen, Chuan; Ren, Nanqi; Wang, Aijie; Lee, Duu-Jong

2011-05-01

Denitrifying sulfide removal (DSR) processes simultaneously convert sulfide, nitrate, and chemical oxygen demand from industrial wastewater into elemental sulfur, dinitrogen gas, and carbon dioxide, respectively. The failure of a DSR process is signaled by high concentrations of sulfide in reactor effluent. Conventionally, DSR reactor failure is blamed for overcompetition for heterotroph to autotroph communities. This study indicates that the elementary sulfur produced by oxidizing sulfide that is a recoverable resource from sulfide-laden wastewaters can be reduced back to sulfide by sulfur-reducing Methanobacterium sp. The Methanobacterium sp. was stimulated with excess organic carbon (acetate) when nitrite was completely consumed by heterotrophic denitrifiers. Adjusting hydraulic retention time of a DSR reactor when nitrite is completely consumed provides an additional control variable for maximizing DSR performance.

Barium ferrite nanoparticles prepared by self-propagating low ...

Indian Academy of Sciences (India)

Administrator

Kubo et al 1982; Lucchini et al 1983), hydrothermal. (Barb et al 1986), microemulsion ... combustion route employing metal oxalate precursors. In search of a suitable ... heptahydrate/barium nitrate and oxalic acid were dis- solved in minimum ...

Study of decomposition kinetics of volatile β-diketonates of yttrium, barium and copper in flow reactor

International Nuclear Information System (INIS)

Devyatykh, G.G.; Gavrishchuk, E.M.; Gibin, A.M.; Dadanov, A.Yu.; Dzyubenko, N.G.; Kaul', A.R.; Nichiporuk, R.V.; Snezhko, N.T.; Ul'yanov, A.A.

1990-01-01

Heterogeneous oxidative decomposition of adduct of yttrium acetylacetonate with o-phenanthroline, copper acetylacetonate and barium dipivaloylmethanate in a flow-type reactor was carried out. The basic kinetic characteristics of chemical precipitation processes of films of yttrium, copper and barium oxides, which are components of high-temperature superconductors, were obtained. The values of activation energy of precipitation process of yttrium, copper and barium oxides constituted 76±10, 108±15, 81±12 (t 600 deg C) respectively

A Comparative Study on Magnetostructural Properties of Barium Hexaferrite Powders Prepared by Polyethylene Glycol

Directory of Open Access Journals (Sweden)

Zehra Durmus

2014-01-01

Full Text Available Nanocrystalline particles of barium hexaferrite were synthesized by a sol-gel combustion route using nitrate-citrate gels prepared from metal nitrates and citric acid solutions with Fe/Ba molar ratio 12. The present paper aims to study the effect of addition of polyethylene glycol (PEG solutions with different molecular weights (MW: 400, 2000, and 10.000 g/mol on magnetostructural properties of barium hexaferrite. The formation of the barium hexaferrite was inspected using X-ray diffraction (XRD analysis, Fourier transform infrared (FT-IR analysis, thermogravimetric (TGA analysis, scanning electron microscopy (SEM analysis and vibrating sample magnetometer (VSM analysis for magnetic measurements.

Enhanced sulfidation xanthate flotation of malachite using ammonium ions as activator.

Science.gov (United States)

Wu, Dandan; Ma, Wenhui; Mao, Yingbo; Deng, Jiushuai; Wen, Shuming

2017-05-18

In this study, ammonium ion was used to enhance the sulfidation flotation of malachite. The effect of ammonium ion on the sulfidation flotation of malachite was investigated using microflotation test, inductively coupled plasma (ICP) analysis, zeta potential measurements, and scanning electron microscope analysis (SEM). The results of microflotation test show that the addition of sodium sulfide and ammonium sulfate resulted in better sulfidation than the addition of sodium sulfide alone. The results of ICP analysis indicate that the dissolution of enhanced sulfurized malachite surface is significantly decreased. Zeta potential measurements indicate that a smaller isoelectric point value and a large number of copper-sulfide films formed on the malachite surface by enhancing sulfidation resulted in a large amount of sodium butyl xanthate absorbed onto the enhanced sulfurized malachite surface. EDS semi-quantitative analysis and XPS analysis show that malachite was easily sulfurized by sodium sulfide with ammonium ion. These results show that the addition of ammonium ion plays a significant role in the sulfidation of malachite and results in improved flotation performance.

Barium promotes anchorage-independent growth and invasion of human HaCaT keratinocytes via activation of c-SRC kinase.

Science.gov (United States)

Thang, Nguyen Dinh; Yajima, Ichiro; Kumasaka, Mayuko Y; Ohnuma, Shoko; Yanagishita, Takeshi; Hayashi, Rumiko; Shekhar, Hossain U; Watanabe, Daisuke; Kato, Masashi

2011-01-01

Explosive increases in skin cancers have been reported in more than 36 million patients with arsenicosis caused by drinking arsenic-polluted well water. This study and previous studies showed high levels of barium as well as arsenic in the well water. However, there have been no reports showing a correlation between barium and cancer. In this study, we examined whether barium (BaCl(2)) may independently have cancer-related effects on human precancerous keratinocytes (HaCaT). Barium (5-50 µM) biologically promoted anchorage-independent growth and invasion of HaCaT cells in vitro. Barium (5 µM) biochemically enhanced activities of c-SRC, FAK, ERK and MT1-MMP molecules, which regulate anchorage-independent growth and/or invasion. A SRC kinase specific inhibitor, protein phosphatase 2 (PP2), blocked barium-mediated promotion of anchorage-independent growth and invasion with decreased c-SRC kinase activity. Barium (2.5-5 µM) also promoted anchorage-independent growth and invasion of fibroblasts (NIH3T3) and immortalized nontumorigenic melanocytes (melan-a), but not transformed cutaneous squamous cell carcinoma (HSC5 and A431) and malignant melanoma (Mel-ret) cells, with activation of c-SRC kinase. Taken together, our biological and biochemical findings newly suggest that the levels of barium shown in drinking well water independently has the cancer-promoting effects on precancerous keratinocytes, fibroblast and melanocytes in vitro.

The role of the Ganges-Brahmaputra mixing zone in supplying barium and 226Ra to the Bay of Bengal

International Nuclear Information System (INIS)

Carroll, J.; Falkner, K.K.; Brown, E.T.; Moore, W.S.

1993-01-01

The Ganges-Brahmaputra river system is ranked fourth among world rivers as a source of freshwater to the oceans and is believed to supply more sediment to the ocean than any other; 1.5 x 10 12 kg/yr (Milliman and Meade, 1983). Barium and 226 Ra are typically enriched in waters where sediment-laden rivers enter the ocean. As such, the Ganges-Brahmaputra is likely to produce globally significant barium and 226 Ra fluxes to the ocean. Water samples for barium and 226 Ra were collected within four major channels of the Ganges-Brahmaputra mixing zone during a period of low sediment and freshwater discharge. The data suggest that in addition to suspended sediments supplied directly from rivers, river sediments deposited during high discharge in mangroves and on islands are desorbing barium and 226 Ra to seawater. The release of barium and 226 Ra from these sediment deposits is out-of-phase with the direct supply of sediments from the rivers. Estimates of the annual fluxes of barium and 226 Ra from the Ganges-Brahmaputra mixing zone were also derived. The fluxes of barium and 226 Ra are 5.3 x 10 8 mol barium/yr and 9.5 x 10 14 dpm radium/yr. The first silicate and phosphate mixing profiles for this system are reported. 29 refs., 6 figs., 3 tabs

Indentation plasticity of barium titanate single crystals: Dislocation influence on ferroelectric domain walls

Energy Technology Data Exchange (ETDEWEB)

Liu, D. [Department of Mechanical Engineering, University of Houston, 4800 Calhoun Road, Houston, TX 77204 (United States)]. E-mail: duo.liu@mail.uh.edu; Chelf, M. [Department of Mechanical Engineering, University of Houston, 4800 Calhoun Road, Houston, TX 77204 (United States); White, K.W. [Department of Mechanical Engineering, University of Houston, 4800 Calhoun Road, Houston, TX 77204 (United States)

2006-10-15

The plastic behaviors of barium titanate (001) and (110) single crystals are studied with atomic force microscopy and piezoresponse force microscopy (PFM) following nanoindendation damage. Plastic deformation mechanisms of ferroelectric barium titanate single crystals are discussed with a focus on the interaction between PFM response and dislocation activities. Nanoindentation tests indicate that the theoretical strength is approached prior to the first pop-in event, consistent with the creation of dislocation nucleation sites required for the onset of plasticity. Surface topographic and piezoelectric analyses indicate that pile-ups around indents result from dislocation activities on the primary slip system, {l_brace}110{r_brace}{sub pc}<11-bar 0>{sub pc}. The more complex indentation-induced domain patterns observed on (110) barium titanate are also discussed.

Physiological behavior of hydrogen sulfide in rice plant. Part 5. Effect of hydrogen sulfide on respiration of rice roots

Energy Technology Data Exchange (ETDEWEB)

Okajima, H; Takagi, S

1955-01-01

The inhibitory effects of hydrogen sulfide on the respiration of rice plant roots were investigated using Warburg's manometory technique. Hydrogen sulfide inhibited not only aerobic respiration but anaerobic respiration process of roots. Inhibitory action of hydrogen sulfide and potassium cyanide on the respiration were apparently reversible, but the style of recovery reaction from inhibition was somewhat different in each case. Oxygen consumption of roots was increased by addition of ammonium salts, but the same effects were not recognized by the addition of any other salt examined (except nitrate salts). There was close relationship between respiration of roots and assimilation of nitrogen by roots. The increased oxygen uptake by addition of ammonium salt was also inhibited by hydrogen sulfide. The reactivation of this reaction occurred with the recovery of endogenous respiration of roots. 19 references, 8 figures, 3 tables.

Enhanced sulfidation xanthate flotation of malachite using ammonium ions as activator

OpenAIRE

Dandan Wu; Wenhui Ma; Yingbo Mao; Jiushuai Deng; Shuming Wen

2017-01-01

In this study, ammonium ion was used to enhance the sulfidation flotation of malachite. The effect of ammonium ion on the sulfidation flotation of malachite was investigated using microflotation test, inductively coupled plasma (ICP) analysis, zeta potential measurements, and scanning electron microscope analysis (SEM). The results of microflotation test show that the addition of sodium sulfide and ammonium sulfate resulted in better sulfidation than the addition of sodium sulfide alone. The ...

Clearance of barium from the oesophagus with diet cola and metoclopramide: A one stop approach to patients with dysphagia

Energy Technology Data Exchange (ETDEWEB)

Mitchell, J.; Farrow, R.; Hussaini, S.H.; Dalton, H.R

2001-01-01

AIM: To establish a 'one-stop' dysphagia service in which a consultation, barium swallow and endoscopy can all be performed in the same hospital visit. MATERIALS AND METHODS: In order to allow both barium swallow examination and endoscopy to be performed on the same day, a novel technique for clearing barium from the upper gastrointestinal tract was established. Following the barium swallow examination, patients were given diet cola and metoclopramide syrup. If appropriate, an upper gastrointestinal endoscopy was then performed shortly afterwards. The service was piloted for 6 months in which time 25 patients were investigated in this way. RESULTS: All patients were seen within 2 weeks of referral. The mean time between barium swallow and endoscopy was 3 h 38 min (range, 1 h 50 min to 5 h 20 min). In all 24 patients in whom an endoscopy was performed, barium had been satisfactorily cleared from the oesophagus and stomach. CONCLUSION: This technique allows both barium swallow and upper gastrointestinal endoscopy to be performed on the same day, providing a rapid, safe and accurate diagnosis with minimum patient inconvenience. Mitchell, J. (2001)

Clearance of barium from the oesophagus with diet cola and metoclopramide: A one stop approach to patients with dysphagia

International Nuclear Information System (INIS)

Mitchell, J.; Farrow, R.; Hussaini, S.H.; Dalton, H.R.

2001-01-01

AIM: To establish a 'one-stop' dysphagia service in which a consultation, barium swallow and endoscopy can all be performed in the same hospital visit. MATERIALS AND METHODS: In order to allow both barium swallow examination and endoscopy to be performed on the same day, a novel technique for clearing barium from the upper gastrointestinal tract was established. Following the barium swallow examination, patients were given diet cola and metoclopramide syrup. If appropriate, an upper gastrointestinal endoscopy was then performed shortly afterwards. The service was piloted for 6 months in which time 25 patients were investigated in this way. RESULTS: All patients were seen within 2 weeks of referral. The mean time between barium swallow and endoscopy was 3 h 38 min (range, 1 h 50 min to 5 h 20 min). In all 24 patients in whom an endoscopy was performed, barium had been satisfactorily cleared from the oesophagus and stomach. CONCLUSION: This technique allows both barium swallow and upper gastrointestinal endoscopy to be performed on the same day, providing a rapid, safe and accurate diagnosis with minimum patient inconvenience. Mitchell, J. (2001)

Formation of Copper Sulfide Precipitate in Solid Iron

Science.gov (United States)

Urata, Kentaro; Kobayashi, Yoshinao

The growth rate of copper sulfide precipitates has been measured in low carbon steel samples such as Fe-0.3mass%Cu-0.03mass%S-0.1mass%C and Fe-0.1mass%Cu-0.01mass%S- 0.1mass%C. Heat-treatment of the samples was conducted at 1273, 1423 and 1573 K for 100 s - 14.4 ks for precipitation of copper sulfides and then the samples were observed by a scanning electron microscope and a transmission electron microscope to measure the diameter of copper sulfides precipitated in the samples. The growth rate of copper sulfide has been found to be well described by the Ostwald growth model, as follows: R\

Reducing conditions on barium absorption in rice plants cultured in BaSO4-enriched soil doi: 10.4025/actasciagron.v36i1.17539

Directory of Open Access Journals (Sweden)

Marcio Osvaldo Lima Magalhães

2014-01-01

Full Text Available To evaluate the possible solubilization of barium sulfate in soils under reducing conditions and its effects on barium bioavailability, an Oryza sativa pot trial was established. Increasing barium doses and two redox potential conditions were evaluated. The geochemical fractionation data demonstrated that reducing conditions led to an increase in the levels of more labile forms of barium and a reduction in more stable forms. Furthermore, higher doses of barium were found to have a negative impact on grain production. The highest levels of barium accumulation in the leaves, roots, and grains were observed with the highest barium dose under reducing conditions. These results demonstrate that reducing conditions increased barium bioavailability and absorption by rice plants.

An experimental study of Fe-Ni exchange between sulfide melt and olivine at upper mantle conditions: implications for mantle sulfide compositions and phase equilibria

Science.gov (United States)

Zhang, Zhou; von der Handt, Anette; Hirschmann, Marc M.

2018-03-01

The behavior of nickel in the Earth's mantle is controlled by sulfide melt-olivine reaction. Prior to this study, experiments were carried out at low pressures with narrow range of Ni/Fe in sulfide melt. As the mantle becomes more reduced with depth, experiments at comparable conditions provide an assessment of the effect of pressure at low-oxygen fugacity conditions. In this study, we constrain the Fe-Ni composition of molten sulfide in the Earth's upper mantle via sulfide melt-olivine reaction experiments at 2 GPa, 1200 and 1400 °C, with sulfide melt X_{{{Ni}}}^{{{Sulfide}}}={{Ni}}/{{Ni+{Fe}}} (atomic ratio) ranging from 0 to 0.94. To verify the approach to equilibrium and to explore the effect of {f_{{{O}2}}} on Fe-Ni exchange between phases, four different suites of experiments were conducted, varying in their experimental geometry and initial composition. Effects of Ni secondary fluorescence on olivine analyses were corrected using the PENELOPE algorithm (Baró et al., Nucl Instrum Methods Phys Res B 100:31-46, 1995), "zero time" experiments, and measurements before and after dissolution of surrounding sulfides. Oxygen fugacities in the experiments, estimated from the measured O contents of sulfide melts and from the compositions of coexisting olivines, were 3.0 ± 1.0 log units more reduced than the fayalite-magnetite-quartz (FMQ) buffer (suite 1, 2 and 3), and FMQ - 1 or more oxidized (suite 4). For the reduced (suites 1-3) experiments, Fe-Ni distribution coefficients K_{{D}}{}={(X_{{{Ni}}}^{{{sulfide}}}/X_{{{Fe}}}^{{{sulfide}}})}/{(X_{{{Ni}}^{{{olivine}}}/X_{{{Fe}}}^{{{olivine}}})}} are small, averaging 10.0 ± 5.7, with little variation as a function of total Ni content. More oxidized experiments (suite 4) give larger values of K D (21.1-25.2). Compared to previous determinations at 100 kPa, values of K D from this study are chiefly lower, in large part owing to the more reduced conditions of the experiments. The observed difference does not seem

75 FR 33824 - Barium Chloride From China

Science.gov (United States)

2010-06-15

... China Determination On the basis of the record\\1\\ developed in the subject five-year review, the United... China would be likely to lead to continuation or recurrence of material injury to an industry in the... contained in USITC Publication 4157 (June 2010), entitled Barium Chloride from China: Investigation No. 731...

Thermal decomposition of barium valerate in argon

DEFF Research Database (Denmark)

Torres, P.; Norby, Poul; Grivel, Jean-Claude

2015-01-01

The thermal decomposition of barium valerate (Ba(C4H9CO2)(2)/Ba-pentanoate) was studied in argon by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction and hot-stage optical microscopy. Melting takes place in two different steps, at 200 degrees C and 280...

[Comparison of iodinated and barium-containing contrast media of different viscosity in the detection of pharyngeal perforation].

Science.gov (United States)

Keberle, M; Wittenberg, G; Trusen, A; Baumgartner, W; Hahn, D

2001-08-01

In contrast to esophageal perforations, the more radiopaque barium-suspensions are not as important as iodinated aqueous contrast agents for the detection of pharyngeal perforations. This study was performed to find out whether the highly different viscosities (of iodinated and barium-containing contrast agents with comparable radiopacities) are a reason for this. Viscosity, subjective difference in contrast, and CT-density of an iodinated aqueous (Telebrix) and a 50 wt/vol% barium-containing contrast agent (Micropaque) were determined. Moreover, to exclude postoperative perforation, 104 patients were prospectively examined by pharyngography using both contrast media. Pharyngographies of patients with perforation were later compared by two independent readers. All patients with perforation were followed up clinically to exclude complications due to barium administration. In-vitro comparison showed comparable radiopacity but the 50 wt/vol% barium-suspension was much more viscous than the iodinated contrast agent. During pharyngography, totally, 14 perforations were clearly delineated with the iodinated aqueous contrast agent. However, two of them were not detected with the barium-suspension. All the other perforations presented equally. Given a sufficient radiopacity, a low viscosity appears to be essential for a contrast agent to detect especially pharyngeal perforations. Thus, we recommend the sole use of an iodinated contrast agent (at suspicion of aspiration as isoosmolar variant) for this purpose.

In vitro experiments for the development of a high density (HD) barium sulfate contrast medium

International Nuclear Information System (INIS)

Klein, J.

1986-01-01

In vitro experiments with the high-density (HD) barium meal Falibaryt HD are described. Several charges of BaSO 4 were tested together with certain additives influencing dispersion, stability of the suspension, flowability, surface tension etc. Particle size spectra were measured by the manufacturer, VEB Fahlberg-List. With a simple PVC test plate containing several grooves simulating small details (areae gastricae) the diagnostic capabilities of the HD contrast medium were evaluated in an in vitro test. The developed barium meal Falibaryt HD is in its physical and chemical parameters comparable with Prontobario-HD, one of the best HD barium meals. (author)

Nanoporous gold-based microbial biosensor for direct determination of sulfide.

Science.gov (United States)

Liu, Zhuang; Ma, Hanyue; Sun, Huihui; Gao, Rui; Liu, Honglei; Wang, Xia; Xu, Ping; Xun, Luying

2017-12-15

Environmental pollution caused by sulfide compounds has become a major problem for public health. Hence, there is an urgent need to explore a sensitive, selective, and simple sulfide detection method for environmental monitoring and protection. Here, a novel microbial biosensor was developed using recombinant Escherichia coli BL21 (E. coli BL21) expressing sulfide:quinone oxidoreductase (SQR) for sulfide detection. As an important enzyme involved in the initial step of sulfide metabolism, SQR oxidizes sulfides to polysulfides and transfers electrons to the electron transport chain. Nanoporous gold (NPG) with its unique properties was selected for recombinant E. coli BL21 cells immobilization, and then glassy carbon electrode (GCE) was modified by the resulting E. coli/NPG biocomposites to construct an E. coli/NPG/GCE bioelectrode. Due to the catalytic oxidation properties of NPG for sulfide, the electrochemical reaction of the E. coli/NPG/GCE bioelectrode is attributed to the co-catalysis of SQR and NPG. For sulfide detection, the E. coli/NPG/GCE bioelectrode showed a good linear response ranging from 50μM to 5mM, with a high sensitivity of 18.35μAmM -1 cm -2 and a low detection limit of 2.55μM. The anti-interference ability of the E. coli/NPG/GCE bioelectrode is better than that of enzyme-based inhibitive biosensors. Further, the E. coli/NPG/GCE bioelectrode was successfully applied to the detection of sulfide in wastewater. These unique properties potentially make the E. coli/NPG/GCE bioelectrode an excellent choice for reliable sulfide detection. Copyright © 2017 Elsevier B.V. All rights reserved.

LIGNOCELLULOSE NANOCOMPOSITE CONTAINING COPPER SULFIDE

Directory of Open Access Journals (Sweden)

Sanchi Nenkova

2011-04-01

Full Text Available Copper sulfide-containing lignocellulose nanocomposites with improved electroconductivity were obtained. Two methods for preparing the copper sulfide lignocellulose nanocomposites were developed. An optimization of the parameters for obtaining of the nanocomposites with respect to obtaining improved electroconductivity, economy, and lower quantities and concentration of copper and sulfur ions in waste waters was conducted. The mechanisms and schemes of delaying and subsequent connection of copper sulfides in the lignocellulosic matrix were investigated. The modification with a system of 2 components: cupric sulfate pentahydrate (CuSO4. 5H2O and sodium thiosulfate pentahydrate (Na2S2O3.5H2O for wood fibers is preferred. Optimal parameters were established for the process: 40 % of the reduction system; hydromodule M=1:6; and ratio of cupric sulfate pentahydrate:sodium thiosulfate pentahydrate = 1:2. The coordinative connection of copper ions with oxygen atoms of cellulose OH groups and aromatic nucleus in lignin macromolecule was observed.

SALT reveals the barium central star of the planetary nebula Hen 2-39

Science.gov (United States)

Miszalski, B.; Boffin, H. M. J.; Jones, D.; Karakas, A. I.; Köppen, J.; Tyndall, A. A.; Mohamed, S. S.; Rodríguez-Gil, P.; Santander-García, M.

2013-12-01

Classical barium stars are binary systems which consist of a late-type giant enriched in carbon and slow neutron capture (s-process) elements and an evolved white dwarf (WD) that is invisible at optical wavelengths. The youngest observed barium stars are surrounded by planetary nebulae (PNe), ejected soon after the wind accretion of polluted material when the WD was in its preceding asymptotic giant branch (AGB) phase. Such systems are rare but powerful laboratories for studying AGB nucleosynthesis as we can measure the chemical abundances of both the polluted star and the nebula ejected by the polluter. Here, we present evidence for a barium star in the PN Hen 2-39 (PN G283.8-04.2) as one of only a few known systems. The polluted giant is very similar to that found in WeBo 1 (PN G135.6+01.0). It is a cool (Teff = 4250 ± 150 K) giant enhanced in carbon ([C/H] = 0.42 ± 0.02 dex) and barium ([Ba/Fe] = 1.50 ± 0.25 dex). A spectral type of C-R3 C24 nominally places Hen 2-39 amongst the peculiar early R-type carbon stars; however, the barium enhancement and likely binary status mean that it is more likely to be a barium star with similar properties, rather than a true member of this class. An AGB star model of initial mass 1.8 M⊙ and a relatively large carbon pocket size can reproduce the observed abundances well, provided mass is transferred in a highly conservative way from the AGB star to the polluted star (e.g. wind Roche lobe overflow). It also shows signs of chromospheric activity and photometric variability with a possible rotation period of ˜5.5 d likely induced by wind accretion. The nebula exhibits an apparent ring morphology in keeping with the other PNe around barium stars (WeBo 1 and A 70) and shows a high degree of ionization implying the presence of an invisible hot pre-WD companion that will require confirmation with UV observations. In contrast to A 70, the nebular chemical abundance pattern is consistent with non-Type I PNe, in keeping with the

CuO and Ag2O effect on electrical properties of barium vanadate glasses

International Nuclear Information System (INIS)

Bogomolova, L.D.; Glasova, M.N.; Kalygina, V.M.; Spasibkina, S.N.; Khorikov, A.A.

1987-01-01

Effect of CuO on barium vanadate glass (BVG) conductivity on direct and alternating currents in the frequency range (10 2 -10 4 )Hz has been studied. Effect of Ag 2 O has been also studied for comparison, as Ag and Cu have idendical structure of external electron shells (d 10 , S 1 ). CuO introduction to binary barium vanadate glasses as a modificator results in the conductivity improvement on direct and alternating currents conditioned with reducing activation energy of small radius polaron jump, apparently, owing to exchange (ferromagnetic) interaction between V(IV) and Cu(II). Jump activation energy in barium vanadate glasses with Ag 2 O increases and conductivity drops due to the distance increase between vanadium atoms

Barium zirconate-titanate/barium calcium-titanate ceramics via sol-gel process: novel high-energy-density capacitors

International Nuclear Information System (INIS)

Puli, Venkata Sreenivas; Kumar, Ashok; Scott, J F; Katiyar, Ram S; Chrisey, Douglas B; Tomozawa, M

2011-01-01

Lead-free barium zirconate-titanate/barium calcium-titanate, [(BaZr 0.2 Ti 0.80 )O 3 ] 1-x -[(Ba 0.70 Ca 0.30 )TiO 3 ] x (x = 0.10, 0.15, 0.20) (BZT-BCT) ceramics with high dielectric constant, low dielectric loss and moderate electric breakdown field were prepared by the sol-gel synthesis technique. X-ray diffraction patterns revealed tetragonal crystal structure and this was further confirmed by Raman spectra. Well-behaved ferroelectric hysteresis loops and moderate polarizations (spontaneous polarization, P s ∼ 3-6 μC cm -2 ) were obtained in these BZT-BCT ceramics. Frequency-dependent dielectric spectra confirmed that ferroelectric diffuse phase transition (DPT) exists near room temperature. Scanning electron microscope images revealed monolithic grain growth in samples sintered at 1280 deg. C. 1000/ε versus (T) plots revealed ferroelectric DPT behaviour with estimated γ values of ∼1.52, 1.51 and 1.88, respectively, for the studied BZT-BCT compositions. All three compositions showed packing-limited breakdown fields of ∼47-73 kV cm -1 with an energy density of 0.05-0.6 J cm -3 for thick ceramics (>1 mm). Therefore these compositions might be useful in Y5V-type capacitor applications.

Cuprous sulfide as a film insulation for superconductors

International Nuclear Information System (INIS)

Wagner, G.R.; Uphoff, J.H.; Vecchio, P.D.

1982-01-01

The LCP test coil utilizes a conductor of forced-flow design having 486 strands of multifilametary Nb 3 Sn compacted in a stainless steel sheath. The impetus for the work reported here stemmed from the need for some form of insulation for those strands to prevent sintering during reaction and to reduce ac losses. The work reported here experimented with cuprous sulfide coatings at various coating rates and thicknesses. Two solenoids that were wound with cuprous sulfide-coated wires and heat-treated at 700 degrees C were found to demonstrate that the film is effective in providing turn-to-turn insulation for less than about 0.5V between turns. The sulfide layer provided a metal-semiconductor junction which became conducting at roughly 0.5V. Repeated cycling of the coil voltage in excess of that value produced no damage to the sulfide layer. The junction provided self-protection for the coil as long as the upper allowable current density in the sulfide was not exceeded. No training was apparent up to 6.4 T

Remediation of Sulfidic Wastewater by Aeration in the Presence of Ultrasonic Vibration

Directory of Open Access Journals (Sweden)

F. Ahmad

2018-06-01

Full Text Available In the current study, the aerial oxidation of sodium sulfide in the presence of ultrasonic vibration is investigated. Sulfide analysis was carried out by the methylene blue method. Sodium sulfide is oxidized to elemental sulfur in the presence of ultrasonic vibration. The influence of air flow rate, initial sodium sulfide concentration and ultrasonic vibration intensity on the oxidation of sodium sulfide was investigated. The rate law equation regarding the oxidation of sulfide was determined from the experimental data. The order of reaction with respect to sulfide and oxygen was found to be 0.36 and 0.67 respectively. The overall reaction followed nearly first order kinetics.

Synthesis and characterization of M-type barium hexferrite by ultrasonic inter-dispersion of chemical precipitate

International Nuclear Information System (INIS)

Garcia Junior, E.S.; Gomes Junior, G.G.; Ogasawara, T.

2010-01-01

This work is concerned with the study the synthesis and characterization of M-type barium hexaferrite powder by chemical precipitation type and ultrasonic interdispersion of precursor materials Fe(OH) 3 and Ba(OH) 2 ,separately and ultrasonic inter-dispersion, followed by drying and calcining. In order to guide the experimental work was carried out a preliminary thermodynamic analysis of the system Ba-Fe-H 2 O at 25 deg C. The study shows that the phase formation of M-type barium hexaferrite is obtained at a calcination at 1000 deg C, characterized by X-ray diffraction, the grain growth of the final product of synthesis depending on the calcination temperature is visible by SEM. The synthesis method developed in this research is an option to achieve the results that would be obtained if the co-precipitation of ferric and barium hydroxide was thermodynamically possible, where you can get crystallization of barium hexaferrite in a calcination at 1000 deg C. (author)

Girdler-sulfide process physical properties

International Nuclear Information System (INIS)

Neuburg, H.J.; Atherley, J.F.; Walker, L.G.

1977-05-01

Physical properties of pure hydrogen sulfide and of gaseous and liquid solutions of the H 2 S-H 2 O system have been formulated. Tables for forty-nine different properties in the pressure and temperature range of interest to the Girdler-Sulfide (GS) process for heavy water production are given. All properties are presented in SI units. A computer program capable of calculating properties of the pure components as well as gaseous mixtures and liquid solutions at saturated and non-saturated conditions is included. (author)

Pressure-assisted sintering of high purity barium titanate

NARCIS (Netherlands)

van den Cruijsem, S.; Varst, van der P.G.T.; With, de G.; Bortzmeyer, D.; Boussuge, M.; Chartier, Th.; Hausonne, J.M.; Mocellin, A.; Rousset, A.; Thevenot, F.

1997-01-01

The dielectric behaviour of High Purity Barium titanate (HPB) ceramics is strongly dependent on the grain size and porosity. For applications, control of grain size and porosity is required. Pressure-assisted sintering techniques at relatively low temperatures meet these requirements. In this study,

Water-soluble contrast media compared with barium in enteric follow-through

International Nuclear Information System (INIS)

Laerum, F.; Stordahl, A.; Aase, S.

1988-01-01

The local effects and radiographic efficacy of 4 water-soluble contrast media, barium and saline were evaluated in 86 anaesthetized rats with the distal ileum ligated. The rats were observed for 8 hours after instillation of 3 ml of the test substance via orogastric tube. Radiographs were taken after 1, 4 and 8 hours of observation. After 8 hours the intestines were weighed and biopsied for light microscopy, and blood and urine were sampled for testing. Sodium diatrizoate caused increased fluid influx to the bowel lumen and, like barium, provided poorer radiographic images as compared with iohexol, ioxaglate or iodixanol. Barium showed slower progression through the small bowel than the other agents, while sodium diatrizoate was the most rapidly progressing contrast medium and caused the greatest distension. Correlation to osmolality was obvious. No significant morphologic effects on the small bowel mucosa were seen in any of the groups. Low-osmolar, water-soluble contrast media may have prospects for clinical use in patients with suspected small bowel obstruction. (orig.)

Hydrogen sulfide production from cysteine and homocysteine by periodontal and oral bacteria.

Science.gov (United States)

Yoshida, Akihiro; Yoshimura, Mamiko; Ohara, Naoya; Yoshimura, Shigeru; Nagashima, Shiori; Takehara, Tadamichi; Nakayama, Koji

2009-11-01

Hydrogen sulfide is one of the predominant volatile sulfur compounds (VSCs) produced by oral bacteria. This study developed and evaluated a system for detecting hydrogen sulfide production by oral bacteria. L-methionine-alpha-deamino-gamma-mercaptomethane-lyase (METase) and beta carbon-sulfur (beta C-S) lyase were used to degrade homocysteine and cysteine, respectively, to produce hydrogen sulfide. Enzymatic reactions resulting in hydrogen sulfide production were assayed by reaction with bismuth trichloride, which forms a black precipitate when mixed with hydrogen sulfide. The enzymatic activities of various oral bacteria that result in hydrogen sulfide production and the capacity of bacteria from periodontal sites to form hydrogen sulfide in reaction mixtures containing L-cysteine or DL-homocysteine were assayed. With L-cysteine as the substrate, Streptococcus anginosus FW73 produced the most hydrogen sulfide, whereas Porphyromonas gingivalis American Type Culture Collection (ATCC) 33277 and W83 and Fusobacterium nucleatum ATCC 10953 produced approximately 35% of the amount produced by the P. gingivalis strains. Finally, the hydrogen sulfide found in subgingival plaque was analyzed. Using bismuth trichloride, the hydrogen sulfide produced by oral bacteria was visually detectable as a black precipitate. Hydrogen sulfide production by oral bacteria was easily analyzed using bismuth trichloride. However, further innovation is required for practical use.

Early colon cancer : findings on double contrast barium enema

International Nuclear Information System (INIS)

Kim, Seung Kwon; Lim, Jae Hoon; Lee, Soon Jin; Lim, Hyo Keun

1998-01-01

The purpose of this study is to describe the radiologic findings of early colon cancer on double-contrast barium enema. We retrospectively reviewed the double-contrast barium enemas of eight patients (M:F = 6:2; mean age : 67 yrs; range : 48-77 yrs) who were pathologically proven to be early colon cancer. The location, size and gross morphology of lesions was evaluated using double-contrast barium enema, while depth of invasion, degree of differentiation, precancerous lesions and lymph node metastasis were evaluated histopathologically. Early colon cancer was found in the rectum (n=4), sigmoid colon (n=3) and ascending colon (n=1). The size of mass ranged from 2.3 ∼ 8.3 (mean, 4.6) cm. And the polypoid type was most common (n=7); this was subdivided into sessile (Is, n=5), semipedunculated (Isp, n=1) and pedunculated type (Ip, n=1). Another mass was a sessile polypoid combined with a flat depressed lesion. In eight cases, four cancers were confined to the mucosa, while the remaining four had infiltrated the submucosa. Most cancers arose from villous and villotubular adenoma. All cases were well-differentiated adenocarcinoma and no metastasis to lymph nodes had occurred. In early colon cancer, lesions were mainly polypoid and large. Most arose from villous and villotubular adenoma. (author). 19 refs., 1 tab., 3 figs

Calorimetric study of interaction of barium hydroxide with diluted solutions of hydrofluoric acid

International Nuclear Information System (INIS)

Kurbanov, A.R.; Sharipov, D.Sh.

1993-01-01

Present article is devoted to calorimetric study of interaction of barium hydroxide with diluted solutions of hydrofluoric acid. The calorimetric study of interaction of barium hydroxide with diluted solutions of hydrofluoric acid was carried out in order to determine the thermal effects of reactions. The results of interaction of Ba(OH) 4 ·8H 2 O with 5, 10, and 20% solution of hydrofluoric acid were considered.

Barium-induced skeletal muscle paralysis in the rat, and its relationship to human familial periodic paralysis

Science.gov (United States)

Schott, G. D.; McArdle, B.

1974-01-01

An in vivo study of skeletal muscle paralysis induced by intravenous barium chloride has been made in curarized and non-curarized rats. The influence of potassium and calcium chlorides, propranolol, ouabain, and prior adrenalectomy on the paralysis has also been studied. Paralysis is found to be due to a direct effect on skeletal muscle, and to correlate well with the development of hypokalaemia. Possible mechanisms of action of barium are discussed, and attention is drawn to the similarity between barium poisoning and hypokalaemic familial periodic paralysis. PMID:4813426

Three barium diphosphonates with 3-D structures

Science.gov (United States)

Tuikka, Matti; Haukka, Matti; Ahlgrén, Markku

2007-06-01

The gel crystallization method was exploited in this work in order to study the 3-D solid state structures of barium diphosphonates. This technique proved to be an effective tool for the growth of single crystals of diphosphonates for structure analysis. By using this approach, three barium diphosphonates, Ba[HO 3P(CH 2) 2PO 3H] ( 1), Ba 2[O 3P(CH 2) 3PO 3]·3H 2O ( 2) and Ba[HO 3P(CH 2) 4PO 3H] ( 3), with different three dimensional structures, were synthesized and characterized. The structures of compounds 1 and 2 were determined by single crystal X-ray diffraction and the structure of 3 by the powder diffraction method. In the structure of 1, the diphosphonate ligand is completely surrounded by the Ba atoms, which is an unusual arrangement in a diphosphonate system. The structures of 2 and 3 are more conventional. They are organized in typical pillared layers in which the separation of the layers can be adjusted by varying the length of the hydrocarbon chain.

The Novel Formation of Barium Titanate Nanodendrites

Directory of Open Access Journals (Sweden)

Chien-Jung Huang

2014-01-01

Full Text Available The barium titanate (BaTiO3 nanoparticles with novel dendrite-like structures have been successfully fabricated via a simple coprecipitation method, the so-called BaTiO3 nanodendrites (BTNDs. This method was remarkable, fast, simple, and scalable. The growth solution is prepared by barium chloride (BaCl2, titanium tetrachloride (TiCl4, and oxalic acid. The shape and size of BaTiO3 depend on the amount of added BaCl2 solvent. To investigate the influence of amount of BaCl2 on BTNDs, the amount of BaCl2 was varied in the range from 3 to 6 mL. The role of BaCl2 is found to have remarkable influence on the morphology, crystallite size, and formation of dendrite-like structures. The thickness and length of the central stem of BTND were ~300 nm and ~20 μm, respectively. The branchings were found to occur at irregular intervals along the main stem. Besides, the formation mechanism of BTND is proposed and discussed.

Sulfidation of alumina-supported iron and iron-molybdenum oxide catalysts

NARCIS (Netherlands)

Ramselaar, W.L.T.M.; Crajé, M.W.J.; Hadders, R.H.; Gerkema, E.; Beer, de V.H.J.; Kraan, van der A.M.

1990-01-01

The transition of alumina-supported iron and iron-molybdenum catalysts from the oxidic precursor to the sulfided catalysts was systematically studied by means of in-situ Mössbauer spectroscopy at room temperature. This enabled the adjudgement of various sulfidic phases in the sulfided catalysts. The

Clinical efficacy of a new barium sulfate for abdominal CT

International Nuclear Information System (INIS)

Yamada, Tatuya; Kohno, Mitio; Uematsu, Sadao; Nisitani, Hiromu; Tanaka, Takao.

1988-01-01

Computed Tomography of the abdomen requires that the intestines are filled with contrast medium so that the gut is not misinterpreted as a pathologic process. Besides, normal structures may be difficult to delimit in patients with scanty intra-abdominal fat. In Japan, up to date, only a single contrast medium has been available for this purpose, Gastrografin and thus identical with the intravasculaly used Urografin or Angiografin. A new Barium Sulfate suspention (Fusimi Seiyaku, Kagawa) for computed tomographic use has been dilute solution (4.77 %) and with suspending agents that prevent a rapid sedimentation of the Barium Sulfate. The aim of this investigation was to compare Gastrografin with a new barium regarding patients tolerance, side effects and diagnostic information. The investigation comprised 146 patients who were reffered for abdominal CT and was carried out by 5 facilities; National Cancer Center, Kobe University, Chiba University, Kyushu University and Juntendo University. Diagnostic information was judged with respect to the filling of the stomach and intestines, the presence of imaging artifacts and finally clinical estimation. Patients tolerance was investigated as regards taste and side effects. Good filling of the stomach and intestines was obtained in this investigation. However, imaging artifacts occured in only a few cases. The imaging artifacts appeared almost exclusively to arise in the boundary layer between the bowel gas and contrast medium, and were most common in the stomach. However, the contrasting effect of this medium did not in itself appear to cause any imaging artifacts. Fushimi's new barium seems to be preffered because of its lesser tendency to arise artifacts and better tendency to make good filling of the stomach and intestines. Moreover, this investigation did not have any side effects. (J.P.N.)

Red coloration by heat treatment of the coprecipitate of cadmium sulfide and mercury(II) sulfide prepared from the nitrates

International Nuclear Information System (INIS)

Nakahara, Fujiya

1979-01-01

The effects of starting salts on the color, particle size and crystal structure of mercury-cadmium-sulfide pigments were investigated. The coprecipitate (N-S) of cadmium sulfide and mercury (II) sulfide was prepared by adding sodium sulfide solution to a mixed cadmium-mercury (II) nitrate solution. The coprecipitate (C-S) of cadmium sulfide and mercury (II) sulfide was also prepared from the mixed solution of their chlorides by the same method as described above. The coprecipitated products were heat-treated (calcination or hydrothermal treatment) at 350 0 C for 2 hours and subsequent changes in powder properties of both products were compared from each other. The powder properties of N-S, C-S and their heat-treated products were investigated by spectral reflectance, electron microscopy, X-ray diffraction and specific surface area measurements. Sample (N-C) obtained by the calcination of N-S was brown, indicating no red coloration, but the calcined product (C-C) of C-S developed a red color. Cl - and hot water were found to be effective for the red color development of the pigment. The effectiveness was confirmed by calcining N-S in the presence of NaCl or by treating it hydrothermally. It was found that halides other than NaCl, (e.g., NH 4 Cl, KCl, KBr and KI), were also effective for the color development of the pigment. The red samples are solid solutions with a basically hexagonal CdS structure, and it appears that CdS takes up HgS without any apparent structural changes. The particle size of the red samples are larger than those of the non red samples. (author)

Influence of Magnetron Effect on Barium Hexaferrite Thin Layers

International Nuclear Information System (INIS)

Hassane, H.; Chatelon, J.P.; Rousseau, J.J; Siblini, A.; Kriga, A.

2011-01-01

In this paper, we study the effects of a magnet, located in the cathode, on barium hexaferrite thin films deposited by RF magnetron sputtering technique. During the process, these effects can modify thickness, roughness and stress of coatings. The characteristics of the deposited layers depend on the substrate position that is located opposite of magnetron cathode. In the m agnetron area , one can observe that the high stress can produce cracks or detachment of layers and the increasing of both depositing rate and surface roughness. After sputtering elaboration, barium hexaferrite films are in a compressive stress mode. But, after the post-deposition heat treatment these films are in a tensile stress mode. To improve the quality of BaM films, the subsrtate has to be set outside the magnetron area. (author)

Synthesis and characterization of nickel oxide doped barium strontium titanate ceramics

Energy Technology Data Exchange (ETDEWEB)

Banerjee, M. [Dept. of Electrical Engineering, Bengal Institute of Technology Kolkata (India); Mukherjee, S. [Dept. of Metallurgical Engineering, Jadavpur University, Kolkata (India); Maitra, S. [Govt. College of Engg. and Ceramic Technology, Kolkata (India)

2012-01-15

Barium strontium titanate (BST) ceramics (Ba{sub 0.6}Sr{sub 0.4})TiO{sub 3} were synthesized by solid state sintering using barium carbonate, strontium carbonate and rutile as the precursor materials. The samples were doped with nickel oxide in different proportions. Different phases present in the sintered samples were determined from X-ray diffraction investigation and the distribution of different phases in the microstructure was assessed from scanning electron microscopy study. It was observed that the dielectric properties of BST were modified significantly with nickel oxide doping. These ceramics held promise for applications in tuned circuits. (author)

SAD phasing with in-house cu Ka radiation using barium as anomalous scatterer.

Science.gov (United States)

Dhanasekaran, V; Velmurugan, D

2011-12-01

Phasing of lysozyme crystals using co-crystallized barium ions was performed using single-wavelength anomalous diffraction (SAD) method using Cu Ka radiation with in-house source of data collection. As the ion binding sites vary with respect to the pH of the buffer during crystallization, the highly isomorphic forms of lysozyme crystals grown at acidic and alkaline pH were used for the study. Intrinsic sulphur anomalous signal was also utilized with anomalous signal from lower occupancy ions for phasing. The study showed that to solve the structure by SAD technique, 2.8-fold data redundancy was sufficient when barium was used as an anomalous marker in the in-house copper X-ray radiation source for data collection. Therefore, co-crystallization of proteins with barium containing salt can be a powerful tool for structure determination using lab source.

A method for measuring sulfide toxicity in the nematode Caenorhabditis elegans.

Science.gov (United States)

Livshits, Leonid; Gross, Einav

2017-01-01

Cysteine catabolism by gut microbiota produces high levels of sulfide. Excessive sulfide can interfere with colon function, and therefore may be involved in the etiology and risk of relapse of ulcerative colitis, an inflammatory bowel disease affecting millions of people worldwide. Therefore, it is crucial to understand how cells/animals regulate the detoxification of sulfide generated by bacterial cysteine catabolism in the gut. Here we describe a simple and cost-effective way to explore the mechanism of sulfide toxicity in the nematode Caenorhabditis elegans ( C. elegans ). •A rapid cost-effective method to quantify and study sulfide tolerance in C. elegans and other free-living nematodes.•A cost effective method to measure the concentration of sulfide in the inverted plate assay.

Production of autoionizing di-excited states of barium with high angular momentum

International Nuclear Information System (INIS)

Roussel, F.; Breger, P.; Gounand, F.; Spiess, G.

1988-01-01

Autoionizing di-excited states Ba(6p 1/2 27l) with 7 ≤l≤26, have been experimentally detected. They have been produced by a method combining excitation by two lasers and l-mixing collisions between barium and xenon. Results show that a long delay between the two laser excitation steps is favourable to the production of these states. The method has proved to be very efficient (measured cross-section: σ = 3.1 . 10 -13 cm 2 ) for populating high-angular-momentum autoionizing states of barium

Influence of Water Salinity on Air Purification from Hydrogen Sulfide

Directory of Open Access Journals (Sweden)

Leybovych L.I.

2015-12-01

Full Text Available Mathematical modeling of «sliding» water drop motion in the air flow was performed in software package FlowVision. The result of mathematical modeling of water motion in a droplet with diameter 100 microns at the «sliding» velocity of 15 m/s is shown. It is established that hydrogen sulfide oxidation occurs at the surface of phases contact. The schematic diagram of the experimental setup for studying air purification from hydrogen sulfide is shown. The results of the experimental research of hydrogen sulfide oxidation by tap and distilled water are presented. The dependence determining the share of hydrogen sulfide oxidized at the surface of phases contact from the dimensionless initial concentration of hydrogen sulfide in the air has been obtained.

ORIGINAL ARTICLE ORIG ORIG Comparison of barium and ...

African Journals Online (AJOL)

SA JOURNAL OF RADIOLOGY • June 2007. ORIG. Abstract. Background. Simulation of patients with carcinoma of the oesophagus using radio-opaque contrast is a standard step in treatment planning prior to delivering radiation therapy. Various contrast mediums such as barium, gastrograffin and hexabrix have been used ...

Sulfidation of carbon-supported iron oxide catalysts

NARCIS (Netherlands)

Ramselaar, W.L.T.M.; Hadders, R.H.; Gerkema, E.; Beer, de V.H.J.; Oers, van E.M.; Kraan, van der A.M.

1989-01-01

The sulfidation of carbon-supported iron oxide catalysts was studied by means of in-situ Mössbauer spectroscopy at temperatures down to 4.2 K. The catalysts were dried in two different ways and then sulfided in a flow of 10% H2S in H2 at temperatures between 293 and 773 K. Thiophene

Structural and optical study of tellurite-barium glasses

Science.gov (United States)

Grelowska, I.; Reben, M.; Burtan, B.; Sitarz, M.; Cisowski, J.; Yousef, El Sayed; Knapik, A.; Dudek, M.

2016-12-01

The goal of this work was to determine the effect of barium oxide on the structural, thermal and optical properties of the TeO2-BaO-Na2O (TBN) and TeO2-BaO-WO3 (TBW) glass systems. Raman spectra allow relating the glass structure and vibration properties (i.e. vibrational frequencies and Raman intensities) with the glass composition. Raman spectra show the presence of TeO4 and TeO3+1/TeO3 units that conform with the glass matrix. Differential thermal analysis DTA, XRD measurements have been considered in term of BaO addition. The spectral dependence of ellipsometric angles of the tellurite-barium glass has been studied. The optical measurements were conducted on Woollam M2000 spectroscopic ellipsometer in spectral range of 190-1700 nm. The reflectance and transmittance measurements have been done on spectrophotometer Perkin Elmer, Lambda 900 in the range of 200-2500 nm (UV-VIS-NIR). From the transmittance spectrum, the energy gap was determined.

Optimization of the superconducting phase of hydrogen sulfide

Science.gov (United States)

Degtyarenko, N. N.; Masur, E. A.

2015-12-01

The electron and phonon spectra, as well as the densities of electron and phonon states of the SH3 phase and the stable orthorhombic structure of hydrogen sulfide SH2, are calculated for the pressure interval 100-225 GPa. It is found that the I4/ mmm phase can be responsible for the superconducting properties of metallic hydrogen sulfide along with the SH3 phase. Sequential stages for obtaining and conservation of the SH2 phase are proposed. The properties of two (SH2 and SH3) superconducting phases of hydrogen sulfide are compared.

Chemical dissolution of sulfide minerals

Science.gov (United States)

Chao, T.T.; Sanzolone, R.F.

1977-01-01

Chemical dissolution treatments involving the use of aqua regia, 4 N HNO3, H2O2-ascorbic acid, oxalic acid, KClO3+HCl, and KClO3+HCl followed by 4 N HNO3 were applied to specimens of nine common sulfide minerals (galena, chalcopyrite, cinnabar, molybdenite, orpiment, pyrite, stibnite, sphalerite, and tetrahedrite) mixed individually with a clay loam soil. The resultant decrease in the total sulfur content of the mixture, as determined by using the Leco induction furnace, was used to evaluate the effectiveness of each chemical treatment. A combination of KClO3+HCl followed by 4 N HNO3 boiling gently for 20 min has been shown to be very effective in dissolving all the sulfide minerals. This treatment is recommended to dissolve metals residing in sulfide minerals admixed with secondary weathering products, as one step in a fractionation scheme whereby metals in soluble and adsorbed forms, and those associated with organic materials and secondary oxides, are first removed by other chemical extractants.

Lanthanide complexes as luminogenic probes to measure sulfide levels in industrial samples

International Nuclear Information System (INIS)

Thorson, Megan K.; Ung, Phuc; Leaver, Franklin M.; Corbin, Teresa S.; Tuck, Kellie L.; Graham, Bim; Barrios, Amy M.

2015-01-01

A series of lanthanide-based, azide-appended complexes were investigated as hydrogen sulfide-sensitive probes. Europium complex 1 and Tb complex 3 both displayed a sulfide-dependent increase in luminescence, while Tb complex 2 displayed a decrease in luminescence upon exposure to NaHS. The utility of the complexes for monitoring sulfide levels in industrial oil and water samples was investigated. Complex 3 provided a sensitive measure of sulfide levels in petrochemical water samples (detection limit ∼ 250 nM), while complex 1 was capable of monitoring μM levels of sulfide in partially refined crude oil. - Highlights: • Lanthanide–azide based sulfide sensors were synthesized and characterized. • The probes have excitation and emission profiles compatible with sulfide-contaminated samples from the petrochemical industry. • A terbium-based probe was used to measure the sulfide concentration in oil refinery wastewater. • A europium-based probe had compatibility with partially refined crude oil samples.

Lanthanide complexes as luminogenic probes to measure sulfide levels in industrial samples

Energy Technology Data Exchange (ETDEWEB)

Thorson, Megan K. [Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, UT 84108 (United States); Ung, Phuc [Monash Institute of Pharmaceutical Sciences, Monash University, Victoria 3052 (Australia); Leaver, Franklin M. [Water & Energy Systems Technology, Inc., Kaysville, UT 84037 (United States); Corbin, Teresa S. [Quality Services Laboratory, Tesoro Refining and Marketing, Salt Lake City, UT 84103 (United States); Tuck, Kellie L., E-mail: kellie.tuck@monash.edu [School of Chemistry, Monash University, Victoria 3800 (Australia); Graham, Bim, E-mail: bim.graham@monash.edu [Monash Institute of Pharmaceutical Sciences, Monash University, Victoria 3052 (Australia); Barrios, Amy M., E-mail: amy.barrios@utah.edu [Department of Medicinal Chemistry, University of Utah College of Pharmacy, Salt Lake City, UT 84108 (United States)

2015-10-08

A series of lanthanide-based, azide-appended complexes were investigated as hydrogen sulfide-sensitive probes. Europium complex 1 and Tb complex 3 both displayed a sulfide-dependent increase in luminescence, while Tb complex 2 displayed a decrease in luminescence upon exposure to NaHS. The utility of the complexes for monitoring sulfide levels in industrial oil and water samples was investigated. Complex 3 provided a sensitive measure of sulfide levels in petrochemical water samples (detection limit ∼ 250 nM), while complex 1 was capable of monitoring μM levels of sulfide in partially refined crude oil. - Highlights: • Lanthanide–azide based sulfide sensors were synthesized and characterized. • The probes have excitation and emission profiles compatible with sulfide-contaminated samples from the petrochemical industry. • A terbium-based probe was used to measure the sulfide concentration in oil refinery wastewater. • A europium-based probe had compatibility with partially refined crude oil samples.

Calculations of energy levels and lifetimes of low-lying states of barium and radium

International Nuclear Information System (INIS)

Dzuba, V. A.; Ginges, J. S. M.

2006-01-01

We use the configuration-interaction method and many-body perturbation theory to perform accurate calculations of energy levels, transition amplitudes, and lifetimes of low-lying states of barium and radium. Calculations for radium are needed for the planning of measurements of parity- and time-invariance-violating effects which are strongly enhanced in this atom. Calculations for barium are used to control the accuracy of the calculations

The solubility of iron sulfides and their role in mass transport in Girdler-Sulfide heavy water plants

International Nuclear Information System (INIS)

Tewari, P.H.; Wallace, G.; Campbell, A.B.

1978-04-01

The solubilities of several iron sulfides, mackinawite FeSsub((1-x)), troilite FeS, pyrrhotite Fesub((1-x))S (monoclinic and hexagonal), and pyrite FeS 2 have been determined in aqueous H 2 S solution at 0.1 MPa and 1.8 MPa H 2 S pressures between 25 deg and 125 deg C. The dependence of solubility on the pH of the medium has also been studied. It is concluded that since mackinawite is the most soluble of the iron sulfides, and has the highest dissolution rate and the steepest decline in solubility with temperature, its prolonged formation during plant operation should be avoided to minimize iron transport from lower to higher temperature areas in Girdler-Sulfide (G.S.) heavy water plants. This can be achieved by a preconditioning of carbon steel surfaces to convert mackinawite to pyrrhotite and pyrite

Laser cleaning of sulfide scale on compressor impeller blade

International Nuclear Information System (INIS)

Tang, Q.H.; Zhou, D.; Wang, Y.L.; Liu, G.F.

2015-01-01

Highlights: • The effects of sulfide layers and fluence values on the mechanism of laser cleaning were experimentally established. • The specimen surface with sulfide scale becomes slightly smoother than that before laser cleaning. • The mechanism of laser cleaning the sulfide scale of stainless steel is spallation without oxidization. • It would avoid chemical waste and dust pollution using a fiber laser instead of using nitric acids or sandblasting. - Abstract: Sulfide scale on the surface of a compressor impeller blade can considerably reduce the impeller performance and its service life. To prepare for subsequent remanufacturing, such as plasma spraying, it needs to be removed completely. In the corrosion process on an FV(520)B stainless steel, sulfide scale is divided into two layers because of different outward diffusion rates of Cr, Ni and Fe. In this paper, the cleaning threshold values of the upper and inner layers and the damage threshold value of the substrate were investigated using a pulsed fiber laser. To obtain experimental evidence, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and 3D surface profilometry were employed to investigate the two kinds of sulfide layers on specimens before, during, and after laser cleaning.

Environmental consequences of the placement of radium-barium sludge in tailings areas

International Nuclear Information System (INIS)

Huck, P.M.; Brown, J.R.; Multimaki, G.; Murphy, K.L.

1982-01-01

A preliminary evaluation was made of the implications of placing radium-barium sludge in tailings areas. The study was restricted to a consideration of possible increases in the quantities of radionuclides escaping to the environment through either groundwater or surface water, considering the types of tailings treated and the effluent treatment systems currently operating in Canada. It was concluded that the placement of radium/barium sludge in tailings areas should not adversely affect the long-term stability of the radionuclides in the tailings or sludge, based on geochemical inorganic reactions

Double contrast with technique of Insufflated Barium Meal in the radiological study of the esophagus

International Nuclear Information System (INIS)

Gallina, F.; Piga, V.; Gallina, M.S.

1985-01-01

The results are reported of the esophagus double contrast examination with Insufflated Barium Meal technique as first part of the routine upper digestive system radiological examination. This technique gives good double contrast without those artifacts using effervescent powders and without modifying the normal radiological alimentary tract examination established way. The double contrast is administered by a special container with a built-in mouthpiece which allows the simultaneous ingestion of barium suspension and air. The esophageal mucosa can be examined as far as the distal tract where frequently the barium contrast stops using different techniques. Good results in 90% of patients have been obtained. The early detection of inflammatory and tumoral lesions has taken particular advantage in patients sometimes asymptomatic

Double contrast with technique of Insufflated Barium Meal in the radiological study of the esophagus

Energy Technology Data Exchange (ETDEWEB)

Gallina, F; Piga, V; Gallina, M.S. and others

1985-01-01

The results are reported of the esophagus double contrast examination with Insufflated Barium Meal technique as first part of the routine upper digestive system radiological examination. This technique gives good double contrast without those artifacts using effervescent powders and without modifying the normal radiological alimentary tract examination established way. The double contrast is administered by a special container with a built-in mouthpiece which allows the simultaneous ingestion of barium suspension and air. The esophageal mucosa can be examined as far as the distal tract where frequently the barium contrast stops using different techniques. Good results in 90% of patients have been obtained. The early detection of inflammatory and tumoral lesions has taken particular advantage in patients sometimes asymptomatic.

Barium zirconate-titanate/barium calcium-titanate ceramics via sol-gel process: novel high-energy-density capacitors

Energy Technology Data Exchange (ETDEWEB)

Puli, Venkata Sreenivas; Kumar, Ashok; Scott, J F; Katiyar, Ram S [SPECLAB, Department of Physics, University of Puerto Rico, San Juan, PR 00936 (Puerto Rico); Chrisey, Douglas B; Tomozawa, M, E-mail: rkatiyar@uprrp.edu [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180-3590 (United States)

2011-10-05

Lead-free barium zirconate-titanate/barium calcium-titanate, [(BaZr{sub 0.2}Ti{sub 0.80})O{sub 3}]{sub 1-x}-[(Ba{sub 0.70}Ca{sub 0.30})TiO{sub 3}]{sub x} (x = 0.10, 0.15, 0.20) (BZT-BCT) ceramics with high dielectric constant, low dielectric loss and moderate electric breakdown field were prepared by the sol-gel synthesis technique. X-ray diffraction patterns revealed tetragonal crystal structure and this was further confirmed by Raman spectra. Well-behaved ferroelectric hysteresis loops and moderate polarizations (spontaneous polarization, P{sub s} {approx} 3-6 {mu}C cm{sup -2}) were obtained in these BZT-BCT ceramics. Frequency-dependent dielectric spectra confirmed that ferroelectric diffuse phase transition (DPT) exists near room temperature. Scanning electron microscope images revealed monolithic grain growth in samples sintered at 1280 deg. C. 1000/{epsilon} versus (T) plots revealed ferroelectric DPT behaviour with estimated {gamma} values of {approx}1.52, 1.51 and 1.88, respectively, for the studied BZT-BCT compositions. All three compositions showed packing-limited breakdown fields of {approx}47-73 kV cm{sup -1} with an energy density of 0.05-0.6 J cm{sup -3} for thick ceramics (>1 mm). Therefore these compositions might be useful in Y5V-type capacitor applications.

Spectral K-edge subtraction imaging of experimental non-radioactive barium uptake in bone.

Science.gov (United States)

Panahifar, Arash; Samadi, Nazanin; Swanston, Treena M; Chapman, L Dean; Cooper, David M L

2016-12-01

To evaluate the feasibility of using non-radioactive barium as a bone tracer for detection with synchrotron spectral K-edge subtraction (SKES) technique. Male rats of 1-month old (i.e., developing skeleton) and 8-month old (i.e., skeletally mature) were orally dosed with low dose of barium chloride (33mg/kg/day Ba 2+ ) for 4weeks. The fore and hind limbs were dissected for imaging in projection and computed tomography modes at 100μm and 52μm pixel sizes. The SKES method utilizes a single bent Laue monochromator to prepare a 550eV energy spectrum to encompass the K-edge of barium (37.441keV), for collecting both 'above' and 'below' the K-edge data sets in a single scan. The SKES has a very good focal size, thus limits the 'crossover' and motion artifacts. In juvenile rats, barium was mostly incorporated in the areas of high bone turnover such as at the growth plate and the trabecular surfaces, but also in the cortical bone as the animals were growing at the time of tracer administration. However, the adults incorporated approximately half the concentration and mainly in the areas where bone remodeling was predominant and occasionally in the periosteal and endosteal layers of the diaphyseal cortical bone. The presented methodology is simple to implement and provides both structural and functional information, after labeling with barium, on bone micro-architecture and thus has great potential for in vivo imaging of pre-clinical animal models of musculoskeletal diseases to better understand their mechanisms and to evaluate the efficacy of pharmaceuticals. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

Synthesis and properties of nickel-doped nanocrystalline barium hexaferrite ceramic materials

Science.gov (United States)

Waqar, Moaz; Rafiq, Muhammad Asif; Mirza, Talha Ahmed; Khalid, Fazal Ahmad; Khaliq, Abdul; Anwar, Muhammad Sabieh; Saleem, Murtaza

2018-04-01

M-type barium hexaferrite ceramics have emerged as important materials both for technological and commercial applications. However, limited work has been reported regarding the investigation of nanocrystalline Ni-doped barium hexaferrites. In this study, nanocrystalline barium hexaferrite ceramics with the composition BaFe12- x Ni x O19 (where x = 0, 0.3 and 0.5) were synthesized by sol-gel method and characterized using X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer and precision impedance analyzer. All the synthesized samples had single magnetoplumbite phase having space group P63/mmc showing the successful substitution of Ni in BaFe12O19 without the formation of any impurity phase. Average grain size of undoped samples was around 120 nm which increased slightly with the addition of Ni. Saturation magnetization ( M s) and remnant magnetization ( M r) increased with the addition of Ni, however, coercivity ( H c) decreased with the increase in Ni from x = 0 to x = 0.5. Real and imaginary parts of permittivity decreased with the increasing frequency and increased with Ni content. Dielectric loss and conductivity showed slight variation with the increase in Ni concentration.

Attainment of barium hexaferrite nanoparticles by a Pechini Method

International Nuclear Information System (INIS)

Galvao, S.B.; Timoteo, Jr.J.F.; Melo, G.M.; Souto, K.K.O.; Florioto, N.T.; Paskocimas, C.A.

2009-01-01

The barium hexaferrites (BaFe 12 O 19 ) are used as a compound of materials applied in electronic devices, as medical devices, satellites, dada servers systems, wireless systems and others. The general properties are strongly related to the microstructure and morphology, and the particles size decrease results in advantages to the majority applications, mainly the high-tech thumbnail devices. These magnetic ceramic materials, with perovskite structure, are traditionally prepared my conventional oxide mixture synthesis. In this work was studied the nanoparticle synthesis of BaFe 12 O 19 by the precursors polymeric method (Pechini), using as precursors the barium carbonate and the iron nitrate, under different thermal treatment conditions. The samples were characterized by XRD, SEM, BET, DTA and TGA. The results presented the attainment of a monophasic powder with particles size around 100 nm. (author)

Laser-Induced Fluorescence diagnostic of barium ion plasmas in the Paul Trap Simulator Experiment

International Nuclear Information System (INIS)

Chung, Moses; Gilson, Erik P.; Davidson, Ronald C.; Efthimion, Philip C.; Majeski, Richard; Startsev, Edward A.

2005-01-01

The Paul Trap Simulator Experiment (PTSX) is a cylindrical Paul trap whose purpose is to simulate the nonlinear dynamics of intense charged particle beam propagation in alternating-gradient magnetic transport systems. To investigate the ion plasma microstate in PTSX, including the ion density profile and the ion velocity distribution function, a laser-induced fluorescence diagnostic system is being developed as a nondestructive diagnostic. Instead of cesium, which has been used in the initial phase of the PTSX experiment, barium has been selected as the preferred ion for the laser-induced fluorescence diagnostic. A feasibility study of the laser-induced fluorescence diagnostic using barium ions is presented with the characterization of a tunable dye laser. The installation of the barium ion source and the development of the laser-induced fluorescence diagnostic system are also discussed

Effect of Sodium Sulfide on Ni-Containing Carbon Monoxide Dehydrogenases

Energy Technology Data Exchange (ETDEWEB)

Jian Feng; Paul A. Lindahl

2004-07-28

OAK-B135 The structure of the active-site C-cluster in CO dehydrogenase from Carboxythermus hydrogenoformans includes a {mu}{sup 2}-sulfide ion bridged to the Ni and unique Fe, while the same cluster in enzymes from Rhodospirillum rubrum (CODH{sub Rr}) and Moorella thermoacetica (CODH{sub Mt}) lack this ion. This difference was investigated by exploring the effects of sodium sulfide on activity and spectral properties. Sulfide partially inhibited the CO oxidation activity of CODH{sub Rr} and generated a lag prior to steady-state. CODH{sub Mt} was inhibited similarly but without a lag. Adding sulfide to CODH{sub Mt} in the C{sub red1} state caused the g{sub av} = 1.82 EPR signal to decline and new features to appear, including one with g = 1.95, 1.85 and (1.70 or 1.62). Removing sulfide caused the g{sub av} = 1.82 signal to reappear and activity to recover. Sulfide did not affect the g{sub av} = 1.86 signal from the C{sub red2} state. A model was developed in which sulfide binds reversibly to C{sub red1}, inhibiting catalysis. Reducing this adduct causes sulfide to dissociate, C{sub red2} to develop, and activity to recover. Using this model, apparent K{sub I} values are 40 {+-} 10 nM for CODH{sub Rr} and 60 {+-} 30 {micro}M for CODH{sub Mt}. Effects of sulfide are analogous to those of other anions, including the substrate hydroxyl group, suggesting that these ions also bridge the Ni and unique Fe. This proposed arrangement raises the possibility that CO binding labilizes the bridging hydroxyl and increases its nucleophilic tendency towards attacking Ni-bound carbonyl.

Sulfide-iron interactions in domestic wastewater from a gravity sewer

NARCIS (Netherlands)

Nielsen, A.H.; Lens, P.N.L.; Vollertsen, J.; Hvitved-Jacobsen, Th.

2005-01-01

Interactions between iron and sulfide in domestic wastewater from a gravity sewer were investigated with particular emphasis on redox cycling of iron and iron sulfide formation. The concentration ranges of iron and total sulfide in the experiments were 0.4-5.4 mg Fe L-1 and 0-5.1 mg S L-1,

Optimization of biological sulfide removal in a CSTR bioreactor.

Science.gov (United States)

Roosta, Aliakbar; Jahanmiri, Abdolhossein; Mowla, Dariush; Niazi, Ali; Sotoodeh, Hamidreza

2012-08-01

In this study, biological sulfide removal from natural gas in a continuous bioreactor is investigated for estimation of the optimal operational parameters. According to the carried out reactions, sulfide can be converted to elemental sulfur, sulfate, thiosulfate, and polysulfide, of which elemental sulfur is the desired product. A mathematical model is developed and was used for investigation of the effect of various parameters on elemental sulfur selectivity. The results of the simulation show that elemental sulfur selectivity is a function of dissolved oxygen, sulfide load, pH, and concentration of bacteria. Optimal parameter values are calculated for maximum elemental sulfur selectivity by using genetic algorithm as an adaptive heuristic search. In the optimal conditions, 87.76% of sulfide loaded to the bioreactor is converted to elemental sulfur.

Process for scavenging hydrogen sulfide from hydrocarbon gases

International Nuclear Information System (INIS)

Fox, I.

1981-01-01

A process for scavenging hydrogen sulfide from hydrocarbon gases utilizes iron oxide particles of unique chemical and physical properties. These particles have large surface area, and are comprised substantially of amorphous Fe 2 O 3 containing a crystalline phase of Fe 2 O 3 , Fe 3 O 4 and combinations thereof. In scavenging hydrogen sulfide, the iron oxide particles are suspended in a liquid which enters into intimate mixing contact with hydrocarbon gases; the hydrogen sulfide is reacted at an exceptional rate and only acid-stable reaction products are formed. Thereafter, the sweetened hydrocarbon gases are collected

Denitrifying sulfide removal process on high-salinity wastewaters.

Science.gov (United States)

Liu, Chunshuang; Zhao, Chaocheng; Wang, Aijie; Guo, Yadong; Lee, Duu-Jong

2015-08-01

Denitrifying sulfide removal (DSR) process comprising both heterotrophic and autotrophic denitrifiers can simultaneously convert nitrate, sulfide, and acetate into nitrogen gas, elemental sulfur (S(0)), and carbon dioxide, respectively. Sulfide- and nitrate-laden wastewaters at 2-35 g/L NaCl were treated by DSR process. A C/N ratio of 3:1 was proposed to maintain high S(0) conversion rate. The granular sludge with a compact structure and smooth outer surface was formed. The microbial communities of DSR consortium via high-throughput sequencing method suggested that salinity shifts the predominating heterotrophic denitrifiers at 10 g/L NaCl.

Monitoring sulfide and sulfate-reducing bacteria

Energy Technology Data Exchange (ETDEWEB)

Tanner, R.S.

1995-12-31

Simple yet precise and accurate methods for monitoring sulfate-reducing bacteria (SRB) and sulfide remain useful for the study of bacterial souring and corrosion. Test kits are available to measure sulfide in field samples. A more precise methylene blue sulfide assay for both field and laboratory studies is described here. Improved media, compared to that in API RP-38, for enumeration of SRB have been formulated. One of these, API-RST, contained cysteine (1.1 mM) as a reducing agent, which may be a confounding source of sulfide. While cysteine was required for rapid enumeration of SRB from environmental samples, the concentration of cysteine in medium could be reduced to 0.4 mM. It was also determined that elevated levels of yeast extract (>1 g/liter) could interfere with enumeration of SRB from environmental samples. The API-RST medium was modified to a RST-11 medium. Other changes in medium composition, in addition to reduction of cysteine, included reduction of the concentration of phosphate from 3.4 mM to 2.2 mM, reduction of the concentration of ferrous iron from 0.8 mM to 0.5 mM and preparation of a stock mineral solution to ease medium preparation. SRB from environmental samples could be enumerated in a week in this medium.

Follow-up barium study after a negative water-soluble contrast examination for suspected esophageal leak: is it necessary?

Science.gov (United States)

Sanchez, Thomas R; Holz, Grant S; Corwin, Michael T; Wood, Robert J; Wootton-Gorges, Sandra L

2015-10-01

The purpose of this study was to determine the value of follow-up barium esophogram in diagnosing esophageal injury or leak if the initial water-soluble contrast examination of the esophagus is normal. An institutional review board (IRB)-approved retrospective review of all pediatric patients less than 18 years old referred to the radiology department for evaluation of esophageal injury or leak was performed for a 9-year period from 2005 to 2014. The majority of patients had unexplained pneumomediastinum, chest trauma (gunshot or puncture wound), or foreign body ingestion as the reason for the referral. Forty-nine patients (age range 10 days to 17 years) underwent an initial water-soluble esophogram immediately followed by a barium esophogram. Forty-six studies were negative on both water-soluble contrast and barium studies. Two studies were both positive on the initial water-soluble contrast and subsequent barium studies. A single study showed the esophageal leak only in the water-soluble study, with the follow-up barium exam being normal. The result of this study indicates that a single-contrast water-soluble esophogram alone is sensitive in the diagnosis of esophageal injury or leak. It has a 100 % sensitivity and negative predictive value. A follow-up barium esophogram only increases the study time and radiation dose to the patient.

The barium-to-iron enrichment versus age relation of ancient disc stars

Science.gov (United States)

Fuhrmann, K.; Chini, R.; Kaderhandt, L.; Chen, Z.; Lachaume, R.

2017-11-01

We report an intrinsically precise relation of the barium-to-iron enrichment as a function of age for a local, volume-complete (N = 30) sample of ancient Population II (τ ≥ 12 Gyr) and intermediate-disc stars (τ ≃ 10 Gyr), which suggests a common, r-process-dominated nucleosynthesis site for both elements in the early stages of the Milky Way. Deviants from this empirical relation are to a large extent identified as formerly known or new blue straggler stars. We report in particular the striking case of the Population II star HD 159062, whose barium overabundance is difficult to explain without wind accretion of s-process material from a former asymptotic giant branch (AGB) primary that very likely survived as a white dwarf companion. The weak but significant barium enhancement that we measure for HR 3578 and 104 Tau also suggests that both may be accompanied by faint degenerate companions. If confirmed through precision astrometry or direct imaging observations, this would mean a very efficient method to uncover ancient stellar remnant companions around solar-type stars.

Bioavailability of barium to plants and invertebrates in soils contaminated by barite.

Science.gov (United States)

Lamb, Dane T; Matanitobua, Vitukawalu P; Palanisami, Thavamani; Megharaj, Mallavarapu; Naidu, Ravi

2013-05-07

Barium (Ba) is a nonessential element to terrestrial organisms and is known to be toxic at elevated concentrations. In this study, the bioavailability and toxicity of Ba in barite (BaSO4) contaminated soils was studied using standard test organisms (Lactuca sativa L. "Great Lakes", Eisenia fetida). Contamination resulted from barite mining activities. Barium concentrations in contaminated soils determined by X-ray fluorescence were in the range 0.13-29.2%. Barite contaminated soils were shown to negatively impact both E. fetida and L. sativa relative to control soil. For E. fetida, pore-water concentrations and acid extractable Ba were linearly related to % body weight loss. In L. sativa, pore-water Ba and exchangeable Ba were both strongly related to shoot Ba and shoot biomass production. A negative linear relationship was observed between shoot Ba content and shoot weight (P Barium concentrations in pore-water were lower than predicted from barite solubility estimates but strongly related to exchangeable Ba, indicating an influence of ion exchange on Ba solubility and toxicity to E. fetida and L. sativa.

Is succession in wet calcareous dune slacks affected by free sulfide?

NARCIS (Netherlands)

Adema, EB; van Gemerden, H; Grootjans, AP; Adema, Erwin B.; Grootjans, Ab P.; Rapson, G.

Consequences of sulfide toxicity on succession in wet calcareous dune slacks were investigated. Sulfide may exert an inhibitory effect on dune slack plants, but several pioneer species exhibit ROL (Radial Oxygen Loss) and thereby protect themselves against free sulfide. Under oxic conditions free

Non-toxic lead sulfide nanodots as efficient contrast agents for visualizing gastrointestinal tract.

Science.gov (United States)

Liu, Zhen; Ran, Xiang; Liu, Jianhua; Du, Yingda; Ren, Jinsong; Qu, Xiaogang

2016-09-01

Non-invasive imaging of gastrointestinal (GI) tract using novel but efficient contrast agents is of the most important issues in the diagnosis and prognosis of GI diseases. Here, for the first time, we reported the design and synthesis of biothiol-decorated lead sulfide nanodots, as well as their usages in functional dual-modality imaging of GI tract in vivo. Due to the presence of glutathione on the surface of the nanodots, these well-prepared contrast agents could decrease the unwanted ion leakage, withstand the harsh conditions in GI tract, and avoid the systemic absorption after oral administration. Compared with clinical barium meal and iodine-based contrast agents, these nanodots exhibited much more significant enhancement in contrast efficiency during both 2D X-ray imaging and 3D CT imaging. Different from some conventional invasive imaging modalities, such as gastroscope and enteroscope, non-invasive imaging strategy by using glutathione modified PbS nanodots as contrast agents could reduce the painfulness towards patients, facilitate the imaging procedure, and economize the manipulation period. Moreover, long-term toxicity and bio-distribution of these nanodots after oral administration were evaluated in detail, which indicated their overall safety. Based on our present study, these nanodots could act as admirable contrast agents to integrate X-ray imaging and CT imaging for the direct visualization of GI tract. Copyright © 2016 Elsevier Ltd. All rights reserved.

Titanocene sulfide chemistry

Czech Academy of Sciences Publication Activity Database

Horáček, Michal

2016-01-01

Roč. 314, MAY 2016 (2016), s. 83-102 ISSN 0010-8545 R&D Projects: GA ČR(CZ) GAP207/12/2368 Institutional support: RVO:61388955 Keywords : titanocene sulfide chemistry * photolysis * titanocene hydrosulfides Ti-(SH)n Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 13.324, year: 2016

Theoretical study of phonon dispersion, elastic, mechanical and thermodynamic properties of barium chalcogenides

Science.gov (United States)

Musari, A. A.; Orukombo, S. A.

2018-03-01

Barium chalcogenides are known for their high-technological importance and great scientific interest. Detailed studies of their elastic, mechanical, dynamical and thermodynamic properties were carried out using density functional theory and plane-wave pseudo potential method within the generalized gradient approximation. The optimized lattice constants were in good agreement when compared with experimental data. The independent elastic constants, calculated from a linear fit of the computed stress-strain function, were used to determine the Young’s modulus (E), bulk modulus (B), shear modulus (G), Poisson’s ratio (σ) and Zener’s anisotropy factor (A). Also, the Debye temperature and sound velocities for barium chalcogenides were estimated from the three independent elastic constants. The calculations of phonon dispersion showed that there are no negative frequencies throughout the Brillouin zone. Hence barium chalcogenides have dynamically stable NaCl-type crystal structure. Finally, their thermodynamic properties were calculated in the temperature range of 0-1000 K and their constant-volume specific heat capacities at room-temperature were reported.

Effects of polyacrylic acid additive on barium sulfate particle morphology

Energy Technology Data Exchange (ETDEWEB)

Li, Jie; Liu, Dandan; Jiang, Hongkun; Wang, Jun; Jing, Xiaoyan; Chen, Rongrong [Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Zhu, Wenting [Department of Gastroenterology, Harbin Medical University Cancer Hospital, Harbin 150081 (China); Han, Shihui [Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); Li, Wanyou [College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001 (China); Wei, Hao, E-mail: weihao7512@126.com [Key Laboratory of Superlight Material and Surface Technology of Ministry of Education, College of Material Science and Chemical Engineering, Harbin Engineering University, Harbin 150001 (China); College of Power and Energy Engineering, Harbin Engineering University, Harbin 150001 (China)

2016-06-01

In this paper, polyacrylic acid (PAA) was used as a growth modifier to control micron-sized barium sulfate particles via a simple precipitation reaction between sodium sulfate and barium chloride at ambient temperature. The barium sulfate particles were exhibited various morphologies, such as monodisperse spheres, ellipsoids, rose-like aggregates, etc. To better understand the formation mechanisms of the various morphologies of these particles, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and thermo-gravimetric analysis (TGA) were employed. It was found that the PAA concentration, pH, and Ba{sup 2+} and SO{sub 4}{sup 2−} ions concentrations were the most important parameters controlling the morphology of the BaSO{sub 4} particles. These parameters affected the BaSO{sub 4} morphology by influencing the interactions between the PAA carboxyl groups and inorganic ions and the conformation change of the PAA molecular chains. Moreover, this work attempts to provide a preliminary understanding of the formation of the spherical BaSO{sub 4} particles with the randomly coiled conformation of the polymer. - Highlights: • Polyacrylic acid (PAA) was used as a growth modifier to control micron-sized BaSO{sub 4} particles. • The PAA/BaSO{sub 4} particles were exhibited various morphologies. • Provide a preliminary understanding of the formation mechanism of BaSO{sub 4} particles.

Magnetic studies of cobalt doped barium hexaferrite nanoparticles prepared by modified sol-gel method

International Nuclear Information System (INIS)

Shalini, M. Govindaraj; Sahoo, Subasa C.

2016-01-01

M-type barium hexaferrite (BaFe_1_2O_1_9) and cobalt doped barium hexaferrite (BaFe_1_1CoO_1_9) nanopowders were synthesized by modified sol-gel auto-combustion technique and were annealed at 900°C in air for 4 hours. The annealed powders were studied in the present work and X-ray diffraction studies showed pure phase formation after annealing. The average grain size in the nanopowder sample was decreased after doping. Magnetization value of 60 emu/g was observed at 300 K for the barium hexaferrite and was reduced to 54 emu/g after doping. The coercivity of 5586 Oe was observed at 300 K for the undoped sample and was found to be decreased in the doped sample. As the measurement temperature was decreased from 300 K to 60 K, magnetization value was increased in both the samples compared to those at 300 K. The coercivity of the undoped sample was found to decrease whereas it was increased for the doped sample at 60 K. The observed magnetic properties may be understood on the basis of modified exchange interaction and anisotropy in the doped sample compared to that of pure barium hexaferrite.

Method of selective dissolution for characterization of particulate forms of radium and barium in natural and waste waters

International Nuclear Information System (INIS)

Benes, P.; Sedlacek, J.; Sebesta, F.; Sandrik, R.

1981-01-01

A new method is proposed for characterization of particulate forms of radium and barium in natural and waste waters. Particulate solids suspended in 1-3 l. of water are first concentrated by membrane filtration or by centrifugation to 20-50 ml of a concentrate which is then filtered through a small-size membrane filter. The solids retained by the filter are successively washed with three selective solvents releasing ''loosely bound'', ''acid soluble'' and ''barium sulfate'' forms of radium and barium. Compositions and volumes of the selective solvents have been chosen using model experiments and partially checked by analysis of natural samples. Radium and barium ''in crystalline detritus'' remain on the filter and are determined after an acid digestion of the filter. The principal criteria and selectivity of the method are discussed. (author)

Effect of barium sulfate contrast medium on rheology and sensory texture attributes in a model food.

Science.gov (United States)

Ekberg, O; Bulow, M; Ekman, S; Hall, G; Stading, M; Wendin, K

2009-03-01

The swallowing process can be visualized using videoradiography, by mixing food with contrast medium, e.g., barium sulfate (BaSO(4)), making it radiopaque. The sensory properties of foods may be affected by adding this medium. To evaluate if and to what extent sensory and rheological characteristics of mango purée were altered by adding barium sulfate to the food. This study evaluated four food samples based on mango purée, with no or added barium sulfate contrast medium (0%, 12.5%, 25.0%, and 37.5%), by a radiographic method, and measured sensory texture properties and rheological characteristics. The sensory evaluation was performed by an external trained panel using quantitative descriptive analysis. The ease of swallowing the foods was also evaluated. The sensory texture properties of mango purée were significantly affected by the added barium in all evaluated attributes, as was the perception of particles. Moreover, ease of swallowing was significantly higher in the sample without added contrast medium. All samples decreased in extensional viscosity with increasing extension rate, i.e., all samples were tension thinning. Shear viscosity was not as dependent on the concentration of BaSO(4) as extensional viscosity. Addition of barium sulfate to a model food of mango purée has a major impact on perceived sensory texture attributes as well as on rheological parameters.

MDCT appearance of the appendix: how does the low-density barium sulfate oral contrast agent affect it?

Science.gov (United States)

Yaghmai, Vahid; Aghaei-Lasboo, Anahita; Brandwein, Warren M; Tochetto, Sandra; Mafi, John N; Miller, Frank H; Nikolaidis, Paul

2011-01-01

We compared the effect of low-density barium sulfate neutral oral contrast agent on the diameter of normal appendix and its luminal content versus that of water on multidetector-row CT. CT scans of 24 patients who had been imaged on two separate occasions for the evaluation of pancreatic pathology, once with water and subsequently with low-density barium sulfate as the neutral oral contrast agent were evaluated (total of 48 scans). Studies were randomized and reviewed in consensus on a workstation in the stack mode by two radiologists blinded to the type of oral contrast. The appendix was measured at baseline and 10 days later to obtain an average diameter. Results of the water and low-density barium sulfate groups were compared using paired t test. Contents of the appendiceal lumen were also noted (gas, fluid, mixed, and collapsed appendix). The average diameter of the appendix for scans obtained with water and low-density barium sulfate was 4.09 ± 0.87 mm (median, 4.22 mm; range, 2.50-5.65 mm) and 4.13 ± 0.93 mm (median, 4 mm, range, 2.2-5.65 mm), respectively. This difference was not statistically significant (P = 0.69). There was no statistically significant difference in the appendiceal content when water or low-density barium sulfate were used as oral contrast (χ (2) = 4.25, P = 0.89). Low-density barium sulfate does not affect appendiceal content or diameter and, therefore, should not adversely affect evaluation of the appendix on multidetector row CT.

Generation of sub-100-fs Stokes pulses upon SRS in a barium nitrate crystal

International Nuclear Information System (INIS)

Konyashchenko, Aleksandr V; Losev, Leonid L; Tenyakov, S Yu

2010-01-01

72-fs pulses are generated at the first Stokes component frequency upon stimulated Raman scattering in a barium nitrate crystal for the radiation of the Ti 3+ :Al 2 O 3 laser with the pulse duration of 50 fs. The energy efficiency of conversion is 20%. The barium nitrate crystal was optically pumped by two consecutive orthogonally polarised chirped pulses with the following time compression of the Stokes radiation pulse. (nonlinear optical phenomena)

Iron-sulfide redox flow batteries

Science.gov (United States)

Xia, Guan-Guang; Yang, Zhenguo; Li, Liyu; Kim, Soowhan; Liu, Jun; Graff, Gordon L

2013-12-17

Iron-sulfide redox flow battery (RFB) systems can be advantageous for energy storage, particularly when the electrolytes have pH values greater than 6. Such systems can exhibit excellent energy conversion efficiency and stability and can utilize low-cost materials that are relatively safer and more environmentally friendly. One example of an iron-sulfide RFB is characterized by a positive electrolyte that comprises Fe(III) and/or Fe(II) in a positive electrolyte supporting solution, a negative electrolyte that comprises S.sup.2- and/or S in a negative electrolyte supporting solution, and a membrane, or a separator, that separates the positive electrolyte and electrode from the negative electrolyte and electrode.

Kinetics of barium sulphate reaction crystallization in crystallizers with internal circulation

Directory of Open Access Journals (Sweden)

J. Koralewska

2008-06-01

Full Text Available Kinetic calculation results describing the observed nucleation and growth rates of barium sulphate crystals precipitated in an integrated reaction-crystallization process in a barium sulphate-ammonium chloride-water system are presented and analyzed. The scope of experiments included two continuous model DTM-type crystallizers (Draft Tube Magma with internal circulation of the suspension forced by a liquid jet-pump device responsible for stable and intensive enough ascending/descending flow of BaSO4 crystal magma in a mixing chamber. For comparison purposes the experimental data corresponding to a continuous DT (Draft Tube crystallizer with propeller agitator are presented and discussed. The various types of laboratory crystallizers used were fed with concentrated water solution of barium chloride (of 10 or 24 mass % and - in a stoichiometric proportion - crystalline ammonium sulphate, assuming isothermal (348 K and hydrodynamic (average residence time of suspension in a crystallizer: 900 s process conditions. The observed nucleation and growth rates of barium sulphate crystals were estimated on the basis of crystal size distributions (CSDs using convenient calculation scheme derived for an MSMPR (Mixed Suspension Mixed Product Removal model approach. Considering the experimental population density distribution courses, a size-dependent growth (SDG phenomenon was taken into account in the kinetic calculations. Five SDG kinetic models recommended in the accessible literature were used for kinetic parameter values estimation. It was proved statistically, that Rojkowski’s two SDG models (hyperbolic and exponential best suit for our own experimental data description. The experimental data presented can be practically applied for improving the constructions of liquid jet-pump DTM crystallizers recommended for reaction crystallization of sparingly soluble inorganic salts (especially for high concentrations of reaction substrates in the modern

Growth kinetics of hydrogen sulfide oxidizing bacteria in corroded concrete from sewers

International Nuclear Information System (INIS)

Jensen, Henriette Stokbro; Lens, Piet N.L.; Nielsen, Jeppe L.; Bester, Kai; Nielsen, Asbjorn Haaning; Hvitved-Jacobsen, Thorkild; Vollertsen, Jes

2011-01-01

Hydrogen sulfide oxidation by microbes present on concrete surfaces of sewer pipes is a key process in sewer corrosion. The growth of aerobic sulfur oxidizing bacteria from corroded concrete surfaces was studied in a batch reactor. Samples of corrosion products, containing sulfur oxidizing bacteria, were suspended in aqueous solution at pH similar to that of corroded concrete. Hydrogen sulfide was supplied to the reactor to provide the source of reduced sulfur. The removal of hydrogen sulfide and oxygen was monitored. The utilization rates of both hydrogen sulfide and oxygen suggested exponential bacterial growth with median growth rates of 1.25 d -1 and 1.33 d -1 as determined from the utilization rates of hydrogen sulfide and oxygen, respectively. Elemental sulfur was found to be the immediate product of the hydrogen sulfide oxidation. When exponential growth had been achieved, the addition of hydrogen sulfide was terminated leading to elemental sulfur oxidation. The ratio of consumed sulfur to consumed oxygen suggested that sulfuric acid was the ultimate oxidation product. To the knowledge of the authors, this is the first study to determine the growth rate of bacteria involved in concrete corrosion with hydrogen sulfide as source of reduced sulfur.

Isolation of Ochrobactrum sp.QZ2 from sulfide and nitrite treatment system

International Nuclear Information System (INIS)

Mahmood, Qaisar; Hu Baolan; Cai Jing; Zheng Ping; Azim, Muhammad Rashid; Jilani, Ghulam; Islam, Ejazul

2009-01-01

A bacterial strain QZ2 was isolated from sludge of anoxic sulfide-oxidizing (ASO) reactor. Based on 16S rDNA sequence analysis and morphology, the isolate was identified as Ochrobactrum sp. QZ2. The strain was facultative chemolithotroph, able of using sulfide to reduce nitrite anaerobically. It produced either elemental sulfur or sulfate as the product of sulfide oxidation, depending on the initial sulfide and nitrite concentrations. The optimum growth pH and temperature for Ochrobactrum sp. QZ2 were found as 6.5-7.0 and 30 deg. C, respectively. The specific growth rate (μ) was found as 0.06 h -1 with a doubling time of 19.75 h; the growth seemed more sensitive to highly alkaline pH. Ochrobactrum sp. QZ2 catalyzed sulfide oxidation to sulfate was more sensitive to sulfide compared with nitrite as indicated by IC 50 values for sulfide and nitrite utilization implying that isolate was relatively more tolerant to nitrite. The comparison of physiology of Ochrobactrum sp. QZ2 with those of other known sulfide-oxidizing bacteria suggested that the present isolate resembled to Ochrobactrum anthropi in its denitrification ability.

Distribution and source of barium in ground water at Cattaraugus Indian Reservation, southwestern New York

Science.gov (United States)

Moore, R.B.; Staubitz, W.W.

1984-01-01

High concentrations of dissolved barium have been found in ground water from bedrock wells on the Seneca Nation of Indians Reservation on Cattaraugus Creek in southwestern New York. Concentrations in 1982 were as high as 23.0 milligrams per liter , the highest found reported from any natural ground-water system in the world. The highest concentrations are in a bedrock aquifer and in small lenses of saturated gravel between bedrock and the overlying till. The bedrock aquifer is partly confined by silt, clay, and till. The high barium concentrations are attributed to dissolution of the mineral barite (BaSO4), which is present in the bedrock and possibly in overlying silt, clay, or till. The dissolution of barite seems to be controlled by action of sulfate-reducing bacteria, which alter the BaSO4 equilibrium by removing sulfate ions and permitting additional barite to dissolve. Ground water from the surficial, unconsolidated deposits and surface water in streams contain little or no barium. Because barium is chemically similar to calcium, it probably could be removed by cation exchange or treatments similar to those used for water softening. (USGS)

Multiple electrical phase transitions in Al substituted barium hexaferrite

Science.gov (United States)

Kumar, Sunil; Supriya, Sweety; Kar, Manoranjan

2017-12-01

Barium hexaferrite is known to be a very good ferromagnetic material. However, it shows very good dielectric properties, i.e., the dielectric constant is comparable to that of the ferroelectric material. However, its crystal symmetry does not allow it to be a ferroelectric material. Hence, the electrical properties have revived the considerable research interest on these materials, not only for academic interest, but also for technological applications. There are a few reports on temperature dependent dielectric behavior of these materials. However, the exact cause of dielectric as well as electrical conductivity is yet to be established. Hence, Al (very good conducting material) substituted barium hexaferrite (BaFe12-xAlxO19, x = 0.0-4.0) has been prepared by following the modified sol-gel method to understand the ac and DC electrical properties of these materials. The crystal structure and parameters have been studied by employing the XRD and FTIR techniques. There are two transition temperatures, which have been observed in the temperature dependent ac dielectric and DC resistivity measurement. The response of dielectric behaviors to temperature is similar to that of the ferroelectric material; however, the dielectric polarization is due to the polaron hopping, which is evident from the DC resistivity analysis. Hence, the present observations lead to understand the electrical properties of barium hexaferrite. The frequency dependent dielectric dispersion can be understood by the modified Debye model. More interestingly, the dielectric constant decreases and DC resistivity increases with the increase in the Al concentration, which has the correlation between bond length modifications in the crystal due to substitution.

Sulfide Oxidation in the Anoxic Black-Sea Chemocline

DEFF Research Database (Denmark)

JØRGENSEN, BB; FOSSING, H.; WIRSEN, CO

1991-01-01

per day, occurred in anoxic water at the top of the sulfide zone concurrent with the highest rates of dark CO2 assimilation. The main soluble oxidized products of sulfide were thiosulfate (68-82%) and sulfate. Indirect evidence was presented for the formation of elemental sulfur which accumulated...... that the measured H2S oxidation rates were 4-fold higher than could be explained by the downward flux of organic carbon and too high to balance the availability of electron acceptors such as oxidized iron or manganese. A nitrate maximum at the lower boundary of the O2 zone did not extend down to the sulfide zone....

Short-cavity squeezing in barium

Science.gov (United States)

Hope, D. M.; Bachor, H-A.; Manson, P. J.; Mcclelland, D. E.

1992-01-01

Broadband phase sensitive noise and squeezing were experimentally observed in a system of barium atoms interacting with a single mode of a short optical cavity. Squeezing of 13 +/- 3 percent was observed. A maximum possible squeezing of 45 +/- 8 percent could be inferred for out experimental conditions, after correction for measured loss factors. Noise reductions below the quantum limit were found over a range of detection frequencies 60-170 MHz and were best for high cavity transmission and large optical depths. The amount of squeezing observed is consistent with theoretical predictions from a full quantum statistical model of the system.

Ammonia synthesis with barium-promoted iron–cobalt alloys supported on carbon

DEFF Research Database (Denmark)

Hagen, Stefan; Barfod, Rasmus; Fehrmann, Rasmus

2003-01-01

Iron–cobalt alloys supported on carbon were investigated as ammonia synthesis catalysts. Barium was found to have a promoting effect for Fe with an optimum atomic ratio Ba/Fe of 0.35. At this Ba loading, a local maximum for the NH3 synthesis activity was found at 4 wt% Co by varying the Fe/Co ratio....... Samples containing only Co and no Fe, however, yielded by far the most active catalysts (7.0 μmol (NH3) g−1 s−1, 673 K, 10 bar). Barium was a very efficient promoter for Co, increasing the NH3 synthesis activity by more than two orders of magnitude compared to the unpromoted Co samples, while...

Duodenal diverticula demonstrated by barium examination

Energy Technology Data Exchange (ETDEWEB)

Christiansen, T.; Thommesen, P.

An investigation for biliary tract calculi and food-stimulated gastro-oesophageal reflux was carried out in 37 patients with duodenal diverticula demonstrated by barium examination. Sixty per cent of the diverticula were located in the descending part of the duodenum. Biliary tract calculi were demonstrated in 38 per cent and food-stimulated gastro-oesophageal reflux in 81 per cent of the patients. The detection of a duodenal diverticulum should result in a supplementary investigation for gallstones and gastrooesophageal reflux and its sequelae.

Kinetics of Indigenous Nitrate Reducing Sulfide Oxidizing Activity in Microaerophilic Wastewater Biofilms

Science.gov (United States)

Villahermosa, Desirée; Corzo, Alfonso; Garcia-Robledo, Emilio; González, Juan M.; Papaspyrou, Sokratis

2016-01-01

Nitrate decreases sulfide release in wastewater treatment plants (WWTP), but little is known on how it affects the microzonation and kinetics of related microbial processes within the biofilm. The effect of nitrate addition on these properties for sulfate reduction, sulfide oxidation, and oxygen respiration were studied with the use of microelectrodes in microaerophilic wastewater biofilms. Mass balance calaculations and community composition analysis were also performed. At basal WWTP conditions, the biofilm presented a double-layer system. The upper microaerophilic layer (~300 μm) showed low sulfide production (0.31 μmol cm-3 h-1) and oxygen consumption rates (0.01 μmol cm-3 h-1). The anoxic lower layer showed high sulfide production (2.7 μmol cm-3 h-1). Nitrate addition decreased net sulfide production rates, caused by an increase in sulfide oxidation rates (SOR) in the upper layer, rather than an inhibition of sulfate reducing bacteria (SRB). This suggests that the indigenous nitrate reducing-sulfide oxidizing bacteria (NR-SOB) were immediately activated by nitrate. The functional vertical structure of the biofilm changed to a triple-layer system, where the previously upper sulfide-producing layer in the absence of nitrate split into two new layers: 1) an upper sulfide-consuming layer, whose thickness is probably determined by the nitrate penetration depth within the biofilm, and 2) a middle layer producing sulfide at an even higher rate than in the absence of nitrate in some cases. Below these layers, the lower net sulfide-producing layer remained unaffected. Net SOR varied from 0.05 to 0.72 μmol cm-3 h-1 depending on nitrate and sulfate availability. Addition of low nitrate concentrations likely increased sulfate availability within the biofilm and resulted in an increase of both net sulfate reduction and net sulfide oxidation by overcoming sulfate diffusional limitation from the water phase and the strong coupling between SRB and NR-SOB syntrophic

Kinetics of Indigenous Nitrate Reducing Sulfide Oxidizing Activity in Microaerophilic Wastewater Biofilms.

Directory of Open Access Journals (Sweden)

Desirée Villahermosa

Full Text Available Nitrate decreases sulfide release in wastewater treatment plants (WWTP, but little is known on how it affects the microzonation and kinetics of related microbial processes within the biofilm. The effect of nitrate addition on these properties for sulfate reduction, sulfide oxidation, and oxygen respiration were studied with the use of microelectrodes in microaerophilic wastewater biofilms. Mass balance calaculations and community composition analysis were also performed. At basal WWTP conditions, the biofilm presented a double-layer system. The upper microaerophilic layer (~300 μm showed low sulfide production (0.31 μmol cm-3 h-1 and oxygen consumption rates (0.01 μmol cm-3 h-1. The anoxic lower layer showed high sulfide production (2.7 μmol cm-3 h-1. Nitrate addition decreased net sulfide production rates, caused by an increase in sulfide oxidation rates (SOR in the upper layer, rather than an inhibition of sulfate reducing bacteria (SRB. This suggests that the indigenous nitrate reducing-sulfide oxidizing bacteria (NR-SOB were immediately activated by nitrate. The functional vertical structure of the biofilm changed to a triple-layer system, where the previously upper sulfide-producing layer in the absence of nitrate split into two new layers: 1 an upper sulfide-consuming layer, whose thickness is probably determined by the nitrate penetration depth within the biofilm, and 2 a middle layer producing sulfide at an even higher rate than in the absence of nitrate in some cases. Below these layers, the lower net sulfide-producing layer remained unaffected. Net SOR varied from 0.05 to 0.72 μmol cm-3 h-1 depending on nitrate and sulfate availability. Addition of low nitrate concentrations likely increased sulfate availability within the biofilm and resulted in an increase of both net sulfate reduction and net sulfide oxidation by overcoming sulfate diffusional limitation from the water phase and the strong coupling between SRB and NR

Diagnosis of gastro-oesophageal reflux in children. Comparison between oesophageal pH and barium examinations

Energy Technology Data Exchange (ETDEWEB)

Al-Khawari, Hanaa A. [Department of Radiology, Al-Amiri Hospital, Kuwait University (Kuwait); Sinan, T.S. [Department of Radiology, Mubarak Al-Kabeer Hospital, Kuwait University (Kuwait); Seymour, Helen [Department of Radiology, St George' s Hospital, Blackshaw Road, London SW17 0QT (United Kingdom)

2002-11-01

Gastro-oesophageal reflux (GOR) is a common disorder encountered during childhood. Early diagnosis and treatment is essential to prevent serious complications. There are several methods for the diagnosis of GOR, with variable opinions regarding which one is the most sensitive and specific. Objective. This is a retrospective study comparing 24-h oesophageal pH monitoring and barium examinations in the diagnosis of GOR in children. Patients and methods. All children referred with signs and/or symptoms of GOR from January to December 1996 at Great Ormond Street Hospital, London, UK, were included in the study. The recorded results (presence or absence of reflux) of barium examinations and 24-h oesophageal pH monitoring studies performed on 169 children were retrospectively reviewed and compared. Results. One-third of patients were below 1 year of age. In all age groups, oesophageal pH probe studies showed a high detection rate (83%) and low incidence of false-negative results (7%) compared to barium examinations, which showed a lower detection rate (43%) and higher incidence of false-negative results (48%). Most GOR-related anatomical abnormalities diagnosed by barium examinations were identified in infants below 1 year of age. Conclusions. We believe that 24-h oesophageal pH monitoring should be used as the first line of investigation for the diagnosis of GOR in all children regardless of the age group. Barium examinations can be reserved for patients below 1 year of age, those going for surgery and those with negative oesophageal pH monitoring results but strong clinical suspicion of GOR. (orig.)

Investigation of the process of co-crystallization of barium and strontium nitrates from the system acetic acid-water

International Nuclear Information System (INIS)

Hubicki, W.; Piskorek, M.

1976-01-01

Co-crystallization of barium nitrate and strontium nitrate from the system CH 3 COOH-H 2 O was investigated by using radioactive tracer Ba 133 . The authors have found that during the crystallization of strontium nitrate from acetic acid solution at 25 0 C, one can obtain a 67-fold lowering of the content of barium in strontium nitrate, a 40-fold lowering of the content of barium in strontium nitrate is at 35 0 C. Strontium nitrate went to the solid phase with 70% efficiency. Acetic acid solutions of 24.5-24.3 per cent weight were used. Attention was paid to the franctionation of barium admixtures during crystallization of strontium nitrate from acetic acid solutions (so called ''isothermic salting out crystallization process'') is in agreement with the logarithmic law of Doerner-Hoskins. Process is characterized by a constant coefficient of surface co-crystallization lambda = 18. The results of investigations show that it is possible to obtain spectrally pure non-barium strontium nitrate as the result of its crystallization from the system CH 3 COOH-H 2 O at a temperature of 25 0 and 35 0 C. (author)

Routine filtration for decubitus radiography during double contrast barium enema examinations

International Nuclear Information System (INIS)

Camellini, V.; Abelli, P.; Marconi, G.

1987-01-01

A wedge-shaped plexiglass compensation filter for use in lateral decubitus radiographs of double contrast barium enema examinations has been designed. This filter, which has been used since February 1985, was compared with a second plexiglass filter, made by E-Z-EM. Voltage and amperage were kept contrast. Two different experiments were conducted in order to demonstrate the benefits of routine use of this compensation filter. First, the changes in skin dose were assessed using an ionization chamber on phantom. Secondly, three radiologists examined a series of 80 consecutive barium enemas without knowing which had been performed using the new filter. Out of the 70 examinations they considered excellent, as many as 45 had been performed with the new filter. Personal experience and the studies described show that the use of a compensation filter improves the accuracy and thus the diagnostic quality of the examinations as it enhances the detail of the anatomic structure of the colon; moreover the filter reduces skin exposure by up to 73.1% (EZ-E-EM filter 47.3%) and, at the same time, less radiographic films are needed. Routine use of a plexiglass compensation filter in lateral decubitus radiographs while performing a double contrast barium enema examination, is strongly recommended especially in obese patients

Nanoscale Zero-Valent Iron for Sulfide Removal from Digested Piggery Wastewater

Directory of Open Access Journals (Sweden)

Sheng-Hsun Chaung

2014-01-01

Full Text Available The removal of dissolved sulfides in water and wastewater by nanoscale zero-valent iron (nZVI was examined in the study. Both laboratory batch studies and a pilot test in a 50,000-pig farm were conducted. Laboratory studies indicated that the sulfide removal with nZVI was a function of pH where an increase in pH decreased removal rates. The pH effect on the sulfide removal with nZVI is attributed to the formation of FeS through the precipitation of Fe(II and sulfide. The saturated adsorption capacities determined by the Langmuir model were 821.2, 486.3, and 359.7 mg/g at pH values 4, 7, and 12, respectively, for nZVI, largely higher than conventional adsorbents such as activated carbon and impregnated activated carbon. The surface characterization of sulfide-laden nZVI using XPS and TGA indicated the formation of iron sulfide, disulfide, and polysulfide that may account for the high adsorption capacity of nZVI towards sulfide. The pilot study showed the effectiveness of nZVI for sulfide removal; however, the adsorption capacity is almost 50 times less than that determined in the laboratory studies during the testing period of 30 d. The complexity of digested wastewater constituents may limit the effectiveness of nZVI. Microbial analysis suggested that the impact of nZVI on the change of microbial species distribution was relatively noticeable after the addition of nZVI.

Sulindac Sulfide, but Not Sulindac Sulfone, Inhibits Colorectal Cancer Growth

Directory of Open Access Journals (Sweden)

Christopher S. Williams

1999-06-01

Full Text Available Sulindac sulfide, a metabolite of the nonsteroidal antiinflammatory drug (NSAID sulindac sulfoxide, is effective at reducing tumor burden in both familial adenomatous polyposis patients and in animals with colorectal cancer. Another sulindac sulfoxide metabolite, sulindac sulfone, has been reported to have antitumor properties without inhibiting cyclooxygenase activity. Here we report the effect of sulindac sulfone treatment on the growth of colorectal carcinoma cells. We observed that sulindac sulfide or sulfone treatment of HCA-7 cells led to inhibition of prostaglandin E2 production. Both sulindac sulfide and sulfone inhibited HCA-7 and HCT-116 cell growth in vitro. Sulindac sulfone had no effect on the growth of either HCA-7 or HCT-116 xenografts, whereas the sulfide derivative inhibited HCA-7 growth in vivo. Both sulindac sulfide and sulfone inhibited colon carcinoma cell growth and prostaglandin production in vitro, but sulindac sulfone had no effect on the growth of colon cancer cell xenografts in nude mice.

INVESTIGATIONS ON BIOCHEMICAL PURIFICATION OF GROUND WATER FROM HYDROGEN SULFIDE

Directory of Open Access Journals (Sweden)

Yu. P. Sedlukho

2015-01-01

Full Text Available The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa. The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality

Detection of colonic polyps in the elderly: Optimization of the single-contrast barium enema examination

International Nuclear Information System (INIS)

Gelfand, D.W.; Chen, Y.M.; Ott, D.J.; Munitz, H.A.

1986-01-01

Single-contrast studies account for 75% of barium enema examinations and are often performed in the elderly. By optimizing all factors, the following results were obtained: for polyps of less than 1 cm, 40 of 57 were detected (sensitivity, 70.2%); for polyps of 1 cm or larger, 33 of 35 were detected (sensitivity, 94%). Overall, 73 of 92 polyps were detected (sensitivity, 79.3%). These sensitivities result from meticulous preparation and the use of compression filming, low-density barium, moderate kilovoltages, high-resolution screens, remote control apparatus, and high-bandpass TV fluoroscopy. The authors conclude that an optimal single-contrast barium enema examination detects colonic polyps with a sensitivity approaching that of the double-contrast study and may be employed in elderly patients who cannot undergo the double-contrast study

Mapping of strain mechanisms in barium titanate by three-dimensional X-ray diffraction

DEFF Research Database (Denmark)

Majkut, Marta

This thesis presents an in-situ three-dimensional study of the grain-scale response of a prototypical piezoelectric ceramic, barium titanate (BT), to an exernally applied electric field. Piezoceramics take advantage of the coupling of electrical and mechanical energies for use in sensors and actu......This thesis presents an in-situ three-dimensional study of the grain-scale response of a prototypical piezoelectric ceramic, barium titanate (BT), to an exernally applied electric field. Piezoceramics take advantage of the coupling of electrical and mechanical energies for use in sensors...

Influence of barium substitution on bioactivity, thermal and physico-mechanical properties of bioactive glass

Energy Technology Data Exchange (ETDEWEB)

Arepalli, Sampath Kumar, E-mail: askumar.rs.cer11@iitbhu.ac.in; Tripathi, Himanshu; Vyas, Vikash Kumar; Jain, Shubham; Suman, Shyam Kumar; Pyare, Ram; Singh, S.P., E-mail: spsinghceram@gmail.com

2015-04-01

Barium with low concentration in the glasses acts as a muscle stimulant and is found in human teeth. We have made a primary study by substituting barium in the bioactive glass. The chemical composition containing (46.1 − X) SiO{sub 2−}–24.3 Na{sub 2}O–26.9 CaO–2.6 P{sub 2}O{sub 5}, where X = 0, 0.4, 0.8, 1.2 and 1.6 mol% of BaO was chosen and melted in an electric furnace at 1400 ± 5 °C. The glasses were characterized to determine their use in biomedical applications. The nucleation and crystallization regimes were determined by DTA and the controlled crystallization was carried out by suitable heat treatment. The crystalline phase formed was identified by using XRD technique. Bioactivity of these glasses was assessed by immersion in simulated body fluid (SBF) for various time periods. The formation of hydroxy carbonate apatite (HCA) layer was identified by FTIR spectrometry, scanning electron microscope (SEM) and XRD which showed the presence of HCA as the main phase in all tested bioactive glass samples. Flexural strength and densities of bioactive glasses have been measured and found to increase with increasing the barium content. The human blood compatibility of the samples was evaluated and found to be pertinent. - Highlights: • In vitro bioactivity of soda-lime–baria-phospho-silicate glass was investigated. • HCA formed on surface of glasses was confirmed by XRD, SEM and FTIR spectrometry. • Mechanical properties of glasses were found to increase with barium addition. • Hemolysis showed that 1.2 mol% BaO bioactive glass exhibited better biocompatibility. • Barium substituted bioactive glasses can be used as bone implants.

Acute inhalation toxicity of carbonyl sulfide

Energy Technology Data Exchange (ETDEWEB)

Benson, J.M.; Hahn, F.F.; Barr, E.B. [and others

1995-12-01

Carbonyl sulfide (COS), a colorless gas, is a side product of industrial procedures sure as coal hydrogenation and gasification. It is structurally related to and is a metabolite of carbon disulfide. COS is metabolized in the body by carbonic anhydrase to hydrogen sulfide (H{sub 2}S), which is thought to be responsible for COS toxicity. No threshold limit value for COS has been established. Results of these studies indicate COS (with an LC{sub 50} of 590 ppm) is slightly less acutely toxic than H{sub 2}S (LC{sub 50} of 440 ppm).

A sulfidation-resistant nickel-base alloy

International Nuclear Information System (INIS)

Lai, G.Y.

1989-01-01

For applications in mildly to moderately sulfidizing environments, stainless steels, Fe-Ni-Cr alloys (e.g., alloys 800 and 330), and more recently Fe-Ni-Cr-Co alloys (e.g., alloy 556) are frequently used for construction of process equipment. However, for many highly sulfidizing environments, few existing commercial alloys have adequate performance. Thus, a new nickel-based alloy containing 27 wt.% Co, 28 wt.% Cr, 4 wt.% Fe, 2.75 wt.% Si, 0.5 wt.% Mn and 0.05 wt.% C (Haynes alloy HR-160) was developed

Electrical transport properties of calcium and barium aluminates

NARCIS (Netherlands)

Metselaar, R.; Hoefsloot, A.M.

1987-01-01

Electrical conductivity and ionic transport numbers have been measured of barium and calcium aluminates with composition CaO·nAl2O3 (n=7/12, 1, 2, 6) and 0.82 BaO·6Al2O3. At room temperatures these compounds are insulators, but at high temperatures mixed conductivity is observed. Ionic transport

Enhanced constitutive invasion activity in human nontumorigenic keratinocytes exposed to a low level of barium for a long time.

Science.gov (United States)

Thang, Nguyen D; Yajima, Ichiro; Ohnuma, Shoko; Ohgami, Nobutaka; Kumasaka, Mayuko Y; Ichihara, Gaku; Kato, Masashi

2015-02-01

We have recently demonstrated that exposure to barium for a short time (≤4 days) and at a low level (5 µM = 687 µg/L) promotes invasion of human nontumorigenic HaCaT cells, which have characteristics similar to those of normal keratinocytes, suggesting that exposure to barium for a short time enhances malignant characteristics. Here we examined the effect of exposure to low level of barium for a long time, a condition mimicking the exposure to barium through well water, on malignant characteristics of HaCaT keratinocytes. Constitutive invasion activity, focal adhesion kinase (FAK) protein expression and activity, and matrix metalloproteinase 14 (MMP14) protein expression in primary cultured normal human epidermal keratinocytes, HaCaT keratinocytes, and HSC5 and A431 human squamous cell carcinoma cells were augmented following an increase in malignancy grade of the cells. Constitutive invasion activity, FAK phosphorylation, and MMP14 expression levels of HaCaT keratinocytes after treatment with 5 µM barium for 4 months were significantly higher than those of control untreated HaCaT keratinocytes. Taken together, our results suggest that exposure to a low level of barium for a long time enhances constitutive malignant characteristics of HaCaT keratinocytes via regulatory molecules (FAK and MMP14) for invasion. © 2013 Wiley Periodicals, Inc.

Microbial oxidation of soluble sulfide in produced water from the Bakkeen Sands

Energy Technology Data Exchange (ETDEWEB)

Gevertz, D.; Zimmerman, S. [Agouron Institute, La Jolla, CA (United States); Jenneman, G.E. [Phillips Petroleum Company, Bartlesville, OK (United States)] [and others

1995-12-31

The presence of soluble sulfide in produced water results in problems for the petroleum industry due to its toxicity, odor, corrosive nature, and potential for wellbore plugging. Sulfide oxidation by indigenous nitrate-reducing bacteria (NRB) present in brine collected from wells at the Coleville Unit (CVU) in Saskatchewan, Canada, was investigated. Sulfide oxidation took place readily when nitrate and phosphate were added to brine enrichment cultures, resulting in a decrease in sulfide levels of 99-165 ppm to nondetectable levels (< 3.3 ppm). Produced water collected from a number of producing wells was screened to determine the time required for complete sulfide oxidation, in order to select candidate wells for treatment. Three wells were chosen, based on sulfide removal in 48 hours or less. These wells were treated down the backside of the annulus with a solution containing 10 mM KNO{sub 3} and 100 {mu}M NaH{sub 2}PO{sub 4}. Following a 24- to 72-hour shut-in, reductions in pretreatment sulfide levels of greater than 90% were observed for two of the wells, as well as sustained sulfide reductions of 50% for at least two days following startup. NRB populations in the produced brine were observed to increase significantly following treatment, but no significant increases in sulfate-reducing bacteria were observed. These results demonstrate the technical feasibility of stimulating indigenous populations of NRB to remediate and control sulfide in produced brine.

Barium titanate inverted opals-synthesis, characterization, and optical properties

Energy Technology Data Exchange (ETDEWEB)

Soten, I.; Miguez, H.; Yang, S.M.; Petrov, S.; Coombs, N.; Tetreault, N.; Ozin, G.A. [Toronto Univ., ON (Canada). Dept. of Chemistry; Matsuura, N.; Ruda, H.E. [Toronto Univ., ON (Canada). Dept. of Metallurgy and Materials Science

2002-01-01

The engineering of cubic or tetragonal polymorphs of nanocrystalline barium titanate inverted opals has been achieved by thermally induced transformations. Optical characterization demonstrated photonic crystal behavior of the opals. The tuning of the ferroelectric-paraelectric transition around the Curie temperature is shown in this paper. (orig.)

Surface modification of malachite with ethanediamine and its effect on sulfidization flotation

Science.gov (United States)

Feng, Qicheng; Zhao, Wenjuan; Wen, Shuming

2018-04-01

Ethanediamine was used to modify the mineral surface of malachite to improve its sulfidization and flotation behavior. The activation mechanism was investigated by adsorption experiments, X-ray photoelectron spectroscopy (XPS) analysis, and zeta potential measurements. Microflotation experiments showed that the flotation recovery of malachite was enhanced after the pretreatment of the mineral particles with ethanediamine prior to the addition of Na2S. Adsorption tests revealed that numerous sulfide ion species in the pulp solution were transferred onto the mineral surface through the formation of more copper sulfide species. This finding was confirmed by the results of the XPS measurements. Ethanediamine modification not only increased the contents of copper sulfide species on the malachite surface but also enhanced the reactivity of the sulfidization products. During sulfidization, Cu(II) species on the mineral surface were reduced into Cu(I) species, and the percentages of S22- and Sn2- relative to the total S increased after modification, resulting in increased surface hydrophobicity. The results of zeta potential measurements showed that the ethanediamine-modified mineral surface adsorbed with more sulfide ion species was advantageous to the attachment of xanthate species, thereby improving malachite floatability. The proposed ethanediamine modification followed by sulfidization xanthate flotation exhibits potential for industrial application.

Bioavailability and stability of mercury sulfide in Armuchee (USA) soil

International Nuclear Information System (INIS)

Han, Fengxiang; Shiyab, Safwan; Su, Yi; Monts, David L.; Waggoner, Charles A.; Matta, Frank B.

2007-01-01

Because of the adverse effects of elemental mercury and mercury compounds upon human health, the U.S. Department of Energy (DOE) is engaged in an on-going effort to monitor and remediate mercury-contaminated DOE sites. In order to more cost effectively implement those extensive remediation efforts, it is necessary to obtain an improved understanding of the role that mercury and mercury compounds play in the ecosystem. We have conducted pilot scale experiments to study the bioavailability of mercury sulfide in an Armuchee (eastern US ) soil. The effects of plants and incubation time on chemical stability and bioavailability of HgS under simulated conditions of the ecosystem have been examined, as has the dynamics of the dissolution of mercury sulfide by various extractants. The results show that mercury sulfide in contaminated Armuchee soil was still to some extent bioavailable to plants. After planting, soil mercury sulfide is more easily dissolved by both 4 M and 12 M nitric acid than pure mercury sulfide reagent. Dissolution kinetics of soil mercury sulfide and pure chemical reagent by nitric acid are different. Mercury release by EDTA from HgS-contaminated soil increased with time of reaction and soil mercury level. Chelating chemicals increase the solubility and bioavailability of mercury in HgS-contaminated soil. (authors)

Effect of Sulfide Concentration on Copper Corrosion in Anoxic Chloride-Containing Solutions

Science.gov (United States)

Kong, Decheng; Dong, Chaofang; Xu, Aoni; Man, Cheng; He, Chang; Li, Xiaogang

2017-04-01

The structure and property of passive film on copper are strongly dependent on the sulfide concentration; based on this, a series of electrochemical methods were applied to investigate the effect of sulfide concentration on copper corrosion in anaerobic chloride-containing solutions. The cyclic voltammetry and x-ray photoelectron spectroscopy analysis demonstrated that the corrosion products formed on copper in anaerobic sulfide solutions comprise Cu2S and CuS. And the corrosion resistance of copper decreased with increasing sulfide concentration and faster sulfide addition, owing to the various structures of the passive films observed by the atomic force microscope and scanning electron microscope. A p-type semiconductor character was obtained under all experimental conditions, and the defect concentration, which had a magnitude of 1022-1023 cm-3, increased with increasing sulfide concentration, resulting in a higher rate of both film growth and dissolution.

Selective Sulfidation of Lead Smelter Slag with Sulfur

Science.gov (United States)

Han, Junwei; Liu, Wei; Wang, Dawei; Jiao, Fen; Qin, Wenqing

2016-02-01

The selective sulfidation of lead smelter slag with sulfur was studied. The effects of temperature, sulfur dosage, carbon, and Na salts additions were investigated based on thermodynamic calculation. The results indicated that more than 96 pct of zinc in the slag could be converted into sulfides. Increasing temperature, sulfur dosage, or Na salts dosage was conducive to the sulfidation of the zinc oxides in the slag. High temperature and excess Na salts would result in the more consumption of carbon and sulfur. Carbon addition not only promoted the selective sulfidation but reduced the sulfur dosage and eliminated the generation of SO2. Iron oxides had a buffering role on the sulfur efficient utilization. The transformation of sphalerite to wurtzite was feasible under reducing condition at high temperature, especially above 1273 K (1000 °C). The growth of ZnS particles largely depended upon the roasting temperature. They were significantly increased when the temperature was above 1273 K (1000 °C), which was attributed to the formation of a liquid phase.

Green Synthesis of Barium Sulfate Particles Using Plant Extracts

Directory of Open Access Journals (Sweden)

Chen Long

2016-01-01

Full Text Available The biological molecules in the extracts of four fruits or vegetables: kiwifruit, oranges, tomato and carrot, were used as templates to synthesize barium sulfate (BaSO4 particles. The products were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray power diffractometry. The results showed that, leaf-shaped barite BaSO4 crystals with toothed edge were obtained with kiwifruit extracts; thorn spherical barium sulfate crystals with diameter of 2-4 micrometers were produced with tomato extracts; rod-like or quasi-spherical BaSO4 crystals with size of several hundred nanometers to several micrometers were gained with orange extracts; while quasi-spherical BaSO4 nano-crystals were obtained with carrot extracts. The formation mechanism of BaSO4 is also discussed, showing that the proteins, carbohydrates, vitamins and organic acids in above four kinds of fruits or vegetables may provide nucleation sites, controlling the growth of BaSO4 crystals with different morphologies.

Study of barium bismuth titanate prepared by mechanochemical synthesis

Directory of Open Access Journals (Sweden)

Lazarević Z.Ž.

2009-01-01

Full Text Available Barium-bismuth titanate, BaBi4Ti4O15 (BBT, a member of Aurivillius bismuth-based layer-structure perovskites, was prepared from stoichiometric amounts of barium titanate and bismuth titanate obtained via mechanochemical synthesis. Mechanochemical synthesis was performed in air atmosphere in a planetary ball mill. The reaction mechanism of BaBi4Ti4O15 and the preparation and characteristics of BBT ceramic powders were studied using XRD, Raman spectroscopy, particle analysis and SEM. The Bi-layered perovskite structure of BaBi4Ti4O15 ceramic forms at 1100 °C for 4 h without a pre-calcination step. The microstructure of BaBi4Ti4O15 exhibits plate-like grains typical for the Bi-layered structured material and spherical and polygonal grains. The Ba2+ addition leads to changes in the microstructure development, particularly in the change of the average grain size.

Barium as a potential indicator of phosphorus in agricultural runoff.

Science.gov (United States)

Ahlgren, Joakim; Djodjic, Faruk; Wallin, Mats

2012-01-01

In many catchments, anthropogenic input of contaminants, and in particular phosphorus (P), into surface water is a mixture of agricultural and sewage runoff. Knowledge about the relative contribution from each of these sources is vital for mitigation of major environmental problems such as eutrophication. In this study, we investigated whether the distribution of trace elements in surface waters can be used to trace the contamination source. Water from three groups of streams was investigated: streams influenced only by agricultural runoff, streams influenced mainly by sewage runoff, and reference streams. Samples were collected at different flow regimes and times of year and analyzed for 62 elements using ICP-MS. Our results show that there are significant differences between the anthropogenic sources affecting the streams in terms of total element composition and individual elements, indicating that the method has the potential to trace anthropogenic impact on surface waters. The elements that show significant differences between sources are strontium (p barium (p barium shows the greatest potential as a tracer for an individual source of anthropogenic input to surface waters. We observed a strong relationship between barium and total P in the investigated samples (R(2) = 0.78), which could potentially be used to apportion anthropogenic sources of P and thereby facilitate targeting of mitigation practices. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Quantitative prediction process and evaluation method for seafloor polymetallic sulfide resources

Directory of Open Access Journals (Sweden)

Mengyi Ren

2016-03-01

Full Text Available Seafloor polymetallic sulfide resources exhibit significant development potential. In 2011, China received the exploration rights for 10,000 km2 of a polymetallic sulfides area in the Southwest Indian Ocean; China will be permitted to retain only 25% of the area in 2021. However, an exploration of seafloor hydrothermal sulfide deposits in China remains in the initial stage. According to the quantitative prediction theory and the exploration status of seafloor sulfides, this paper systematically proposes a quantitative prediction evaluation process of oceanic polymetallic sulfide resources and divides it into three stages: prediction in a large area, prediction in the prospecting region, and the verification and evaluation of targets. The first two stages of the prediction process have been employed in seafloor sulfides prospecting of the Chinese contract area. The results of stage one suggest that the Chinese contract area is located in the high posterior probability area, which indicates good prospecting potential area in the Indian Ocean. In stage two, the Chinese contract area of 48°–52°E has the highest posterior probability value, which can be selected as the reserved region for additional exploration. In stage three, the method of numerical simulation is employed to reproduce the ore-forming process of sulfides to verify the accuracy of the reserved targets obtained from the three-stage prediction. By narrowing the exploration area and gradually improving the exploration accuracy, the prediction will provide a basis for the exploration and exploitation of seafloor polymetallic sulfide resources.

Oxidation of Alcohols by Ferric Nitrate in the Presence of Barium ...

African Journals Online (AJOL)

NJD

Oxidation, ferric nitrate, barium chloride, silica sulphuric acid, heterogeneous or solvent-free conditions. 1. Introduction ... economic advantage and environment protection. ... by TLC. After completion, structure of the product was charac-.

New cyclic sulfides, garlicnins I2, M, N, and O, from Allium sativum.

Science.gov (United States)

Nohara, Toshihiro; Ono, Masateru; Nishioka, Naho; Masuda, Fuka; Fujiwara, Yukio; Ikeda, Tsuyoshi; Nakano, Daisuke; Kinjo, Junei

2018-01-01

One atypical thiolane-type sulfide, garlicnin I 2 (1), two 3,4-dimethylthiolane-type sulfides, garlicnins M (2) and N (3), and one thiabicyclic-type sulfide, garlicnin O (4), were isolated from the acetone extracts of Chinese garlic bulbs, Allium sativum and their structures were characterized. Hypothetical pathways for the production of the respective sulfides were discussed.

Attainment of barium hexa ferrite nanoparticles by a Pechini method

International Nuclear Information System (INIS)

Galvao, Sheila B.; Timoteo, Flavio Junior J.; Machado, Tercio G.; Souto, Kesia K.O.; Floreoto, Neide T.; Paskocimas, Carlos A.

2009-01-01

The barium hexa ferrites (BaFe 12 O 19 ) are used as a compound of materials applied in electronic devices, as medical devices, satellites, dada servers systems, wireless systems and others. The general properties are strongly related to the microstructure and morphology, and the particles size decrease results in advantages to the majority applications, mainly the high-tech thumbnail devices. These magnetic ceramic materials, with perovskite structure, are traditionally prepared my conventional oxide mixture synthesis. In this work was studied the nanoparticle synthesis of BaFe 12 O 19 by the precursors polymeric method (Pechini), using as precursors the barium carbonate and the iron nitrate, under different thermal treatment conditions. The samples were characterized by XRD, Raman spectroscopy, SEM, BET, DTA and TGA. The results presented the attainment of a monophasic powder with particles size around 100 nm. (author)

Enhanced performance of denitrifying sulfide removal process under micro-aerobic condition

International Nuclear Information System (INIS)

Chen Chuan; Ren Nanqi; Wang Aijie; Liu Lihong; Lee, Duu-Jong

2010-01-01

The denitrifying sulfide removal (DSR) process with bio-granules comprising both heterotrophic and autotrophic denitrifiers can simultaneously convert nitrate, sulfide and acetate into di-nitrogen gas, elementary sulfur and carbon dioxide, respectively, at high loading rates. This study determines the reaction rate of sulfide oxidized into sulfur, as well as the reduction of nitrate to nitrite, would be enhanced under a micro-aerobic condition. The presence of limited oxygen mitigated the inhibition effects of sulfide on denitrifier activities, and enhanced the performance of DSR granules. The advantages and disadvantages of applying the micro-aerobic condition to the DSR process are discussed.

Adaptation of cyanobacteria to the sulfide-rich microenvironment of black band disease of coral.

Science.gov (United States)

Myers, Jamie L; Richardson, Laurie L

2009-02-01

Black band disease (BBD) is a cyanobacteria-dominated microbial mat that migrates across living coral colonies lysing coral tissue and leaving behind exposed coral skeleton. The mat is sulfide-rich due to the presence of sulfate-reducing bacteria, integral members of the BBD microbial community, and the sulfide they produce is lethal to corals. The effect of sulfide, normally toxic to cyanobacteria, on the photosynthetic capabilities of five BBD cyanobacterial isolates of the genera Geitlerinema (3), Leptolyngbya (1), and Oscillatoria (1) and six non-BBD cyanobacteria of the genera Leptolyngbya (3), Pseudanabaena (2), and Phormidium (1) was examined. Photosynthetic experiments were performed by measuring the photoincorporation of [(14)C] NaHCO(3) under the following conditions: (1) aerobic (no sulfide), (2) anaerobic with 0.5 mM sulfide, and (3) anaerobic with 0.5 mM sulfide and 10 microM 3-(3',4'-dichlorophenyl)-1,1-dimethylurea (DCMU). All five BBD cyanobacterial isolates tolerated sulfide by conducting sulfide-resistant oxygenic photosynthesis. Five of the non-BBD cyanobacterial isolates did not tolerate sulfide, although one Pseudanabaena isolate continued to photosynthesize in the presence of sulfide at a considerably reduced rate. None of the isolates conducted anoxygenic photosynthesis with sulfide as an electron donor. This is the first report on the physiology of a culture of Oscillatoria sp. found globally in BBD.

Hydrogen sulfide intervention in focal cerebral ischemia/reperfusion injury in rats

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Xin-juan Li

2015-01-01

Full Text Available The present study aimed to explore the mechanism underlying the protective effects of hydrogen sulfide against neuronal damage caused by cerebral ischemia/reperfusion. We established the middle cerebral artery occlusion model in rats via the suture method. Ten minutes after middle cerebral artery occlusion, the animals were intraperitoneally injected with hydrogen sulfide donor compound sodium hydrosulfide. Immunofluorescence revealed that the immunoreactivity of P2X 7 in the cerebral cortex and hippocampal CA1 region in rats with cerebral ischemia/reperfusion injury decreased with hydrogen sulfide treatment. Furthermore, treatment of these rats with hydrogen sulfide significantly lowered mortality, the Longa neurological deficit scores, and infarct volume. These results indicate that hydrogen sulfide may be protective in rats with local cerebral ischemia/reperfusion injury by down-regulating the expression of P2X 7 receptors.

Nanostructured silver sulfide: synthesis of various forms and their application

Science.gov (United States)

Sadovnikov, S. I.; Rempel, A. A.; Gusev, A. I.

2018-04-01

The results of experimental studies on nanostructured silver sulfide are analyzed and generalized. The influence of small particle size on nonstoichiometry of silver sulfide is discussed. Methods for the synthesis of various forms of nanostructured Ag2S including nanopowders, stable colloidal solutions, quantum dots, core–shell nanoparticles and heteronanostructures are described. The advantages and drawbacks of different synthetic procedures are analyzed. Main fields of application of nanostructured silver sulfide are considered. The bibliography includes 184 references.

Sensitivity of single and double contrast barium enema in the detection of colorectal carcinoma

International Nuclear Information System (INIS)

Myllylae, V.; Paeivansalo, M.; Laitinen, S.; Oulu Univ.

1984-01-01

The preoperative barium enema of the 188 colorectal carcinoma patients operated at the Oulu University Central Hospital (Finland) during 1977-1982 were examined retrospectively. Altogether 112 single contrast studies and 87 double contrast studies had been made on these patients. The single contrast barium enemas had resulted in a correct diagnosis of colorectal carcinoma in 93 cases (sensitivity 83%). The correct diagnosis in the double contrast studies numbered 71 (sensitivity 82%). Most of the overlooked carcinomas were located in the caecum, in the sigmoid or the rectum. Most of the errors made in the single contrast studies were due to detection errors and poor evacuation. The most common failures in double contrast enemas were detection errors and nonvisualisation of the sigmoid. The authors recommend use of the double contrast technique and suggest that the two methods of barium enema be used to complement each other. A false negative diagnosis delayed the operation of the colorectal carcinoma patients by 2.2 months (median). (orig.) [de

Barium sulphate preparations for use in double contrast examination of the upper gastrointestinal tract

International Nuclear Information System (INIS)

Anderson, W.; Harthill, J.E.; James, W.B.; Montgomery, D.

1980-01-01

Physical properties relevant to upper gastrointestinal radiology have been compared for five barium sulphate preparations and related to radiographic results. Evaluation of particles (size and stability) and whole suspension (dispersibility and fluidity) resulted in ranking of the preparations generally in accord with that based on radiological experience in double contrast examinations of the stomach. Experiments with extirpated pig stomach revealed a tendency for large particles in a low viscosity barium sulphate suspension to settle in mucosal grooves. This is believed to contribute to good radiographic definition of both the areae gastricae and small lesions. Particle size is therefore important and susceptibility to flocculation, a possible cause of random change in size during use, was assessed by measuring particle electrophoretic mobility under varying conditions; quantitative differences in suspension flow and dispersibility were also demonstrated. Fluidity and dispersibility together with rapid sedimentation of suitably sized particles resistant to flocculation underlie the successful use of low viscosity high density barium sulphate suspensions. (U.K.)

Production and Preservation of Sulfide Layering in Mercury's Magma Ocean

Science.gov (United States)

Boukare, C.-E.; Parman, S. W.; Parmentier, E. M.; Anzures, B. A.

2018-05-01

Mercury's magma ocean (MMO) would have been sulfur-rich. At some point during MMO solidification, it likely became sulfide saturated. Here we present physiochemical models exploring sulfide layer formation and stability.

Obtaining of barium sulfate from solution formed after desulfation of the active mass of scrap lead-acid batteries

Directory of Open Access Journals (Sweden)

O. A. Kalko

2014-03-01

Full Text Available Analyses of literature data about processes for solution utilization formed after desulfation of the active mass of scrap lead-acid batteries is performed. Optimal conditions for obtaining of barium sulfate sediment from ammonium sulfate solute and chemically pure Ba(OH2×8H2O и BaCl2×2H2O were found experimentally. In laboratory the commercial barium sulfate from sulfate solutions, that are waste of recycling process of battery scrap, with application of chloride and barium hydroxide was production. The possibility of using this product were discussed.

Determination of solubility isotherms of barium and strontium nitrates in the system acetic acid-water at 250 C

International Nuclear Information System (INIS)

Hubicki, W.; Piskorek, M.

1976-01-01

Investigastions of the solubility of barium and strontium nitrates were carried out in the system: acetic acid - water at 25 0 C. When one compares the isotherms of solubility of barium and strontium nitrates, one can observe that it is possible to separate the admixtures of barium from strontium nitrates as a result of fractional crystallization of these nitrates from actic acid solution at the temperatures lower than 31.3 0 C, i.e. below the temperature of transformation: Sr(NO 3 ) 2 . 4H 2 O reversible to Sr(NO 3 ) 2 + 4H 2 O for aqueous solution. (author)

Effects of Wood Pollution on Pore-Water Sulfide Levels and Eelgrass Germination

Science.gov (United States)

Ekelem, C.

2016-02-01

Historically, sawmills released wood waste onto coastal shorelines throughout the Pacific Northwest of the USA, enriching marine sediments with organic material. The increase in organic carbon boosts the bacterial reduction of sulfate and results in the production of a toxic metabolite, hydrogen sulfide. Hydrogen sulfide is a phytotoxin and can decrease the growth and survival of eelgrass. This is a critical issue since eelgrass, Zostera marina, forms habitat for many species, stabilizes sediment, and plays a role in nutrient cycling and sediment chemistry. The objective of our study was to determine the effects of wood debris on sediment pore-water hydrogen sulfide concentrations and eelgrass germination. To test the impact of wood inputs on sulfide production and seed germination, we conducted a laboratory mesocosm experiment, adding sawdust to marine sediments and measuring the sulfide levels weekly. We subsequently planted seeds in the mesocosms and measured germination rates. Higher concentrations of sawdust led to higher levels of pore-water hydrogen sulfide and drastically slower eelgrass germination rates. Treatments with greater than 10% wood enrichment developed free sulfide concentrations of 0.815 (± 0.427) mM after 118 days, suggesting sediments with greater than 10% wood pollution may have threateningly high pore-water hydrogen sulfide levels. These results can be used to set thresholds for remediation efforts and guide seed distribution in wood polluted areas.

Iatrogen perforation of the rectum following barium enema

International Nuclear Information System (INIS)

Eggum, R.; Kressner, U.; Haffner, J.

1998-01-01

Perforation of the rectum following barium enema is relatively rare, occurring in 1 of 3,000 procedures. Colorectal perforation is a serious condition and early diagnosis is of paramount importance in order to avoid any delay in treating the patient. Direct suture of the perforation, lavage, presacral drainage and stomia are the preferred methods of primary surgical treatment. 10 refs., 1 fig

Performance of cement solidification with barium for high activity liquid waste including sulphate

International Nuclear Information System (INIS)

Waki, Toshikazu; Yamada, Motoyuki; Horikawa, Yoshihiko; Kaneko, Masaaki; Saso, Michitaka; Haruguchi, Yoshiko; Yamashita, Yu; Sakai, Hitoshi

2009-01-01

The target liquid waste to be solidified is generated from PWR primary loop spent resin treatment with sulphate acid, so, its main constituent is sodium sulphate and the activity of this liquid is relatively high. Waste form of this liquid waste is considered to be a candidate for the subsurface disposal. The disposed waste including sulphate is anticipated to rise a concentration of sulphate ion in the ground water around the disposal facility and it may cause degradation of materials such as cement and bentonite layer and comprise the disposal facility. There could be two approaches to avoid this problem, the strong design of the disposal facility and the minimization of sulphaste ion migration from the solidified waste. In this study, the latter approach was examined. In order to keep the low concentration of sulphate ion in the ground water, it is effective to make barium sulphate by adding barium compound into the liquid waste in solidification. However, adding equivalent amount of barium compound with sulphate ion causes difficulty of mixing, because production of barium sulphate causes high viscosity. In this study, mixing condition after and before adding cement into the liquid waste was estimated. The mixing condition was set with consideration to keep anion concentration low in the ground water and of mixing easily enough in practical operation. Long term leaching behavior of the simulated solidified waste was also analyzed by PHREEQC. And the concentration of the constitution affected to the disposal facility was estimated be low enough in the ground water. (author)

Anion and cation diffusion in barium titanate and strontium titanate

International Nuclear Information System (INIS)

Kessel, Markus Franz

2012-01-01

Perovskite oxides show various interesting properties providing several technical applications. In many cases the defect chemistry is the key to understand and influence the material's properties. In this work the defect chemistry of barium titanate and strontium titanate is analysed by anion and cation diffusion experiments and subsequent time-of-flight secondary ion mass spectrometry (ToF-SIMS). The reoxidation equation for barium titanate used in multi-layer ceramic capacitors (MLCCs) is found out by a combination of different isotope exchange experiments and the analysis of the resulting tracer diffusion profiles. It is shown that the incorporation of oxygen from water vapour is faster by orders of magnitude than from molecular oxygen. Chemical analysis shows the samples contain various dopants leading to a complex defect chemistry. Dysprosium is the most important dopant, acting partially as a donor and partially as an acceptor in this effectively acceptor-doped material. TEM and EELS analysis show the inhomogeneous distribution of Dy in a core-shell microstructure. The oxygen partial pressure and temperature dependence of the oxygen tracer diffusion coefficients is analysed and explained by the complex defect chemistry of Dy-doped barium titanate. Additional fast diffusion profiles are attributed to fast diffusion along grain boundaries. In addition to the barium titanate ceramics from an important technical application, oxygen diffusion in cubic, nominally undoped BaTiO 3 single crystals has been studied by means of 18 O 2 / 16 O 2 isotope exchange annealing and subsequent determination of the isotope profiles in the solid by ToF-SIMS. It is shown that a correct description of the diffusion profiles requires the analysis of the diffusion through the surface space-charge into the material's bulk. Surface exchange coefficients, space-charge potentials and bulk diffusion coefficients are analysed as a function of oxygen partial pressure and temperature. The

Functional consortium for denitrifying sulfide removal process.

Science.gov (United States)

Chen, Chuan; Ren, Nanqi; Wang, Aijie; Liu, Lihong; Lee, Duu-Jong

2010-03-01

Denitrifying sulfide removal (DSR) process simultaneously converts sulfide, nitrate, and chemical oxygen demand from industrial wastewaters to elemental sulfur, nitrogen gas, and carbon dioxide, respectively. This investigation utilizes a dilution-to-extinction approach at 10(-2) to 10(-6) dilutions to elucidate the correlation between the composition of the microbial community and the DSR performance. In the original suspension and in 10(-2) dilution, the strains Stenotrophomonas sp., Thauera sp., and Azoarcus sp. are the heterotrophic denitrifiers and the strains Paracoccus sp. and Pseudomonas sp. are the sulfide-oxidizing denitrifers. The 10(-4) dilution is identified as the functional consortium for the present DSR system, which comprises two functional strains, Stenotrophomonas sp. strain Paracoccus sp. At 10(-6) dilution, all DSR performance was lost. The functions of the constituent cells in the DSR granules were discussed based on data obtained using the dilution-to-extinction approach.

Activation mechanism of ammonium ions on sulfidation of malachite (-201) surface by DFT study

Science.gov (United States)

Wu, Dandan; Mao, Yingbo; Deng, Jiushuai; Wen, Shuming

2017-07-01

The activation mechanism of ammonium ions on the sulfidation of malachite (-201) was determined by density functional theory (DFT) calculations. Results of DFT calculations indicated that interlayer sulfidation occurs during the sulfidation process of malachite (-201). The absorption of both the ammonium ion and sulfide ion on the malachite (-201) surface is stronger than that of sulfur ion. After sulfidation was activated with ammonium ion, the Cu 3d orbital peak is closer to the Fermi level and characterized by a stronger peak value. Therefore, the addition of ammonium ions activated the sulfidation of malachite (-201), thereby improving the flotation performance.

Hydrogen sulfide generation in shipboard oily-water waste. Part 3. Ship factors

Energy Technology Data Exchange (ETDEWEB)

Hodgeman, D.K.; Fletcher, L.E.; Upsher, F.J.

1995-04-01

The chemical and microbiological composition of bilge-water in ships of the Royal Australian Navy has been investigated in relation to the formation of hydrogen sulfide by sulfate-reducing bacteria. Sulfate-reducing bacteria were found in most ships in populations up to 800,000 per mL. Sulfate in the wastes is provided by sea-water. Sea-water constitutes up to 60% (median 20%) of the wastes analysed. Evidence for generation of hydrogen sulfide in the ships was found directly as sulfide or indirectly as depressed sulfate concentrations. The low levels of sulfide found in bilge-water from machinery spaces suggested the ventilation systems were effectively removing the gas from the working area. The effect of storage of the wastes under conditions which simulated the oily- water holding tanks of ships were also investigated. Some wastes were found to produce large quantities of hydrogen sulfide on storage. The wastes that failed to produce hydrogen sulfide were investigated to identify any specific nutritional deficiencies. Some organic substances present in bilge-water, such as lactate or biodegradable cleaning agents, and phosphate strongly influenced the generation of hydrogen sulfide in stored oily-water wastes.

Study on the sulfidation behavior of smithsonite

International Nuclear Information System (INIS)

Wu, Dandan; Wen, Shuming; Deng, Jiushuai; Liu, Jian; Mao, Yingbo

2015-01-01

Highlights: • Zeta potential showed that the pH IEP of smithsonite decreased from 7.7 to 6. • ICP test showed the gradual reduction of C S in the solution. • SEM showed that the mineral surface was partially changed to ZnS film. • XPS indicated that the presence of a characteristic signal peak of sulfur ions. - Abstract: Zinc extraction from low-grade mineral resources of oxidized zinc has recently become a focus of study. Sulfidation is an important process in oxidized ore flotation. In this study, the influence of sulfur ion adsorption on smithsonite surface was investigated with the use of zeta potential, inductively coupled plasma (ICP), scanning electron microscope (SEM), and X-ray photoelectron spectroscopic studies. Zeta potential measurements of sodium sulfide showed that sulfur ions were adsorbed onto the surface of pure smithsonite, as evidenced by the increased negative charge and the decrease in the pH IEP of smithsonite from 7.7 to 6 after sodium sulfide treatment. The ICP test revealed the gradual reduction in sulfur ion adsorption onto the surface of smithsonite in pulp sulfur. After 30 min of absorption, C S in the solution declined from 1000 × 10 −6 mol/L to 1.4 × 10 −6 mol/L. SEM results showed that the mineral surface was partially changed to ZnS film after sodium sulfide treatment, whereas EDS analysis results showed that 2% S is contained on the smithsonite surface. X-ray photoelectron spectroscopy results indicated the presence of a characteristic signal peak of sulfur ions after sulfidation. Sulfur concentration increased to 11.89%, whereas oxygen concentration decreased from 42.31% to 13.74%. Sulfur ions were not only present during chemical adsorption, but were also incorporated into the crystal lattices of minerals by the exchange reaction between S 2− and CO 3 2− ions

Metal sulfide electrodes and energy storage devices thereof

Science.gov (United States)

Chiang, Yet-Ming; Woodford, William Henry; Li, Zheng; Carter, W. Craig

2017-02-28

The present invention generally relates to energy storage devices, and to metal sulfide energy storage devices in particular. Some aspects of the invention relate to energy storage devices comprising at least one flowable electrode, wherein the flowable electrode comprises an electroactive metal sulfide material suspended and/or dissolved in a carrier fluid. In some embodiments, the flowable electrode further comprises a plurality of electronically conductive particles suspended and/or dissolved in the carrier fluid, wherein the electronically conductive particles form a percolating conductive network. An energy storage device comprising a flowable electrode comprising a metal sulfide electroactive material and a percolating conductive network may advantageously exhibit, upon reversible cycling, higher energy densities and specific capacities than conventional energy storage devices.

Effects of barium chlorine treatment of uranium ore on 222Rn emanation and 226Ra leachability from mill tailings

International Nuclear Information System (INIS)

Ibrahim, S.A.; Church, S.L.; Whicker, F.W.

1985-01-01

The purpose of this laboratory study was to investigate the effectiveness of barium chloride treatment of uranium ore on 222 Rn emanation from mill tailings, 226 Ra level in waste-water, and the leachability of radium from tailings. It has been shown that barium sulfate is an excellent carrier for radium and that barium sulfate crystals have high retention capacity for radon gas produced by radium trapped within the lattice. Ground uranium ore from a mine in Wyoming was mixed with water to form a 1:1 ratio before barium and potassium chlorides were added at concentrations of 0, 10, 25, 50, and 100 mg per liter of slurry. The ore was then subjected to a simulated mill process using sulfuric acid leaching. The liquid representing tailings pond water was separated and analyzed for 226 Ra and the solid fraction, representing mill tailings, was tested for radon emanation and the leachability of radium by deionized water. This study suggests that barium treatment of uranium ore prior to sulfuric acid leaching could be effective in reducing radon emanation from tailings and also in reducing the 226 Ra concentration of waste-water. Leachability of radium from treated tailings was markedly reduced

Sulfide mineralization in ultramafic rocks of the Faryab ophiolite complex, southern Kerman

Directory of Open Access Journals (Sweden)

Mohammad Ali Rajabzadeh

2015-10-01

Full Text Available Introduction Worldwide, Ni-Cu and PGE magmatic sulfide deposits are confined to the lower parts of stratiform mafic and ultramafic complexes. However, ophiolite mafic and ultramafic complexes have been rarely explored for sulfide deposits despite the fact that they have been extensively explored and exploited for chromite. Sulfide saturation during magmatic evolution is necessary for sulfide mineralization, in which sulfide melts scavenge chalcophile metals from the parent magma and concentrate them in specific lithological zones. The lack of exploration for sulfides in this environment suggests that sulfide saturation is rarely attained in ophiolite-related magmas. Some ophiolites, however, contain sulfide deposits, such as at Acoje in Philippines, and Cliffs in Shetland, U.K. (Evans, 2000; Naldrett, 2004. The Faryab ophiolite complex in southern Kerman Province, the most important mining area for chromite deposits in Iran, is located in the southwest part of the Makran Zone. Evidence of sulfide mineralization has been reported there by some authors (e.g. Rajabzadeh and Moosavinasab, 2013. This paper discusses the genesis of sulfides in the Faryab ophiolite using mineral chemistry of the major mineral phases in different rocks of the ophiolite column in order to determine the possible lithological location of sulfide deposits. Materials and methods Seventy three rock samples from cumulate units were collected from surficial occurrences and drill core. The samples were studied using conventional microscopic methods and the mineralogy confirmed by x-ray diffraction. Electron microprobe analysis was carried out on different mineral phases in order to determine the chemistry of the minerals used in the interpretation of magma evolution in the Faryab ophiolite. Lithologically, the Faryab ophiolite complex is divided into two major parts: the northern part includes magmatic rocks and the southern part is comprised of rocks residual after partial

H- Enhancement Process in a Multicusp Ion Source Operated with a Barium Insert Structure

Energy Technology Data Exchange (ETDEWEB)

Leung, K.N.; Van Os, C.F.A.; Kunkel, W.B.

1990-05-01

It has been demonstrated that the H{sup -} output current from a small multicusp source can be substantially enhanced if the hydrogen plasma is seeded with barium. Operating with a barium washer insert at the extraction aperture, it is found that the extractable H{sup -} current is increased by a factor of three if the insert bias potential is optimized. By use of a mixture of xenon and hydrogen gas, it is further demonstrated that the positive hydrogen ions are responsible for the observed H{sup -} enhancement.

Elevated Z line: a new sign of Barrett's esophagus on double-contrast barium esophagograms.

Science.gov (United States)

Levine, Marc S; Ahmad, Nuzhat A; Rubesin, Stephen E

2015-01-01

We describe an elevated Z line as a new radiographic sign of Barrett's esophagus characterized by a transversely oriented, zigzagging, barium-etched line extending completely across the circumference of the midesophagus. An elevated Z line is rarely seen in other patients, so this finding should be highly suggestive of Barrett's esophagus on double-contrast barium esophagograms. If the patient is a potential candidate for surveillance, endoscopy and biopsy should be performed to confirm the presence of Barrett's esophagus. Copyright © 2015 Elsevier Inc. All rights reserved.

Development of novel and sensitive methods for the determination of sulfide in aqueous samples by hydrogen sulfide generation-inductively coupled plasma-atomic emission spectroscopy.

Science.gov (United States)

Colon, M; Todolí, J L; Hidalgo, M; Iglesias, M

2008-02-25

Two new, simple and accurate methods for the determination of sulfide (S(2-)) at low levels (microgL(-1)) in aqueous samples were developed. The generation of hydrogen sulfide (H(2)S) took place in a coil where sulfide reacted with hydrochloric acid. The resulting H(2)S was then introduced as a vapor into an inductively coupled plasma-atomic emission spectrometer (ICP-AES) and sulfur emission intensity was measured at 180.669nm. In comparison to when aqueous sulfide was introduced, the introduction of sulfur as H(2)S enhanced the sulfur signal emission. By setting a gas separator at the end of the reaction coil, reduced sulfur species in the form of H(2)S were removed from the water matrix, thus, interferences could be avoided. Alternatively, the gas separator was replaced by a nebulizer/spray chamber combination to introduce the sample matrix and reagents into the plasma. This methodology allowed the determination of both sulfide and sulfate in aqueous samples. For both methods the linear response was found to range from 5microgL(-1) to 25mgL(-1) of sulfide. Detection limits of 5microgL(-1) and 6microgL(-1) were obtained with and without the gas separator, respectively. These new methods were evaluated by comparison to the standard potentiometric method and were successfully applied to the analysis of reduced sulfur species in environmental waters.

Development of novel and sensitive methods for the determination of sulfide in aqueous samples by hydrogen sulfide generation-inductively coupled plasma-atomic emission spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Colon, M. [Department of Chemistry, University of Girona, Campus Montilivi, 17071 Girona (Spain); Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Todoli, J.L. [Departamento de Quimica Analitica, Nutricion y Bromatologia, University of Alicante, 03080 Alicante (Spain); Hidalgo, M. [Department of Chemistry, University of Girona, Campus Montilivi, 17071 Girona (Spain); Iglesias, M. [Department of Chemistry, University of Girona, Campus Montilivi, 17071 Girona (Spain)], E-mail: monica.iglesias@udg.es

2008-02-25

Two new, simple and accurate methods for the determination of sulfide (S{sup 2-}) at low levels ({mu}g L{sup -1}) in aqueous samples were developed. The generation of hydrogen sulfide (H{sub 2}S) took place in a coil where sulfide reacted with hydrochloric acid. The resulting H{sub 2}S was then introduced as a vapor into an inductively coupled plasma-atomic emission spectrometer (ICP-AES) and sulfur emission intensity was measured at 180.669 nm. In comparison to when aqueous sulfide was introduced, the introduction of sulfur as H{sub 2}S enhanced the sulfur signal emission. By setting a gas separator at the end of the reaction coil, reduced sulfur species in the form of H{sub 2}S were removed from the water matrix, thus, interferences could be avoided. Alternatively, the gas separator was replaced by a nebulizer/spray chamber combination to introduce the sample matrix and reagents into the plasma. This methodology allowed the determination of both sulfide and sulfate in aqueous samples. For both methods the linear response was found to range from 5 {mu}g L{sup -1} to 25 mg L{sup -1} of sulfide. Detection limits of 5 {mu}g L{sup -1} and 6 {mu}g L{sup -1} were obtained with and without the gas separator, respectively. These new methods were evaluated by comparison to the standard potentiometric method and were successfully applied to the analysis of reduced sulfur species in environmental waters.

Pregnancy outcome after 1st-trimester inadvertent exposure to barium sulphate as a contrast media for upper gastrointestinal tract radiography.

Science.gov (United States)

Han, B H; Lee, K S; Han, J Y; Choi, J S; Ahn, H K; Ryu, H M; Yang, J H; Han, H W; Nava-Ocampo, A A

2011-10-01

Despite barium being used as a contrast media for decades, the specific assessment of its safety in pregnant women is scarce. We are reporting the favourable pregnancy outcome in women who were inadvertently exposed to barium swallow and associated ionising radiation, early in pregnancy. A control group of age- and gravidity-matched unexposed pregnant women was also included. There were 32 live-born babies in the exposed group and 94 in the control group. Women had undergone diagnostic upper gastrointestinal tract (UGT) fluoroscopic examination at 3.3 ± 1.5 weeks' gestation. Estimated maternal radiation dose secondary to barium swallow varied widely, the maximum dose was estimated to be 2.45 mSv. Similar pregnancy outcomes were observed between the groups. The number of babies born with major malformations was not significantly different (p = 1.0) between cases and controls: one (3.1%) vs three (3.2%), respectively. In conclusion, our small prospective cohort study of women suggests no association between inadvertent exposure to ionising radiation and barium sulphate during fluoroscopic barium swallow and adverse fetal outcomes.

Revaluation on detection of metastatic cancer of the colorectum with barium enema. Comparison with computed tomography and colonoscopy

International Nuclear Information System (INIS)

Watari, Jiro; Mizukami, Yusuke; Tanabe, Hirotaka

1996-01-01

The findings with barium enema were analyzed and compared to those with computed tomography and colonoscopy in 15 patients with metastatic cancer of the colorectum, which were from 8 gastric, 2 colonic, 2 ovarian, 1 pancreatic, 1 prostatic carcinomas and 1 unknown origin. Primary cancers of intra-abdominal cavity origin tended to make multiple colorectal metastases (91.7%). With barium enema colonic and rectal involvement was mostly expressed as the tethered type and the diffuse type by Ishikawa's classification, respectively. Computed tomography detected direct tumor invasion to the colorectum in 4 cases. Of the other 11 cases, 8 patients (72.3%) showed abnormally thickened colorectal wall. Colonoscopy detected only 3 (37.5%) out of 8 lesions seen in 4 patients who had undergone colonoscopy before barium enema. Many of the lesions missed were the tethered type involvement. Barium enema is the most sensitive method to detect metastatic cancer of the colorectum. (author)

Volcanic sulfur degassing and the role of sulfides in controlling volcanic metal emissions

Science.gov (United States)

Edmonds, M.; Liu, E.

2017-12-01

Volcanoes emit prodigious quantities of sulfur and metals, their behaviour inextricably linked through pre-eruptive sulfide systematics and through degassing and speciation in the volcanic plume. Fundamental differences exist in the metal output of ocean island versus arc volcanoes, with volcanoes in Hawaii and Iceland outgassing large fluxes of gaseous and particulate chalcophiles; and arc volcanoes' plumes, in contrast, enriched in Zn, Cu, Tl and Pb. Metals and metalloids partition into a magmatic vapor phase from silicate melt at crustal pressures. Their abundance in magmatic vapor is influenced strongly by sulfide saturation and by the composition of the magmatic vapor phase, particularly with respect to chloride. These factors are highly dependent on tectonic setting. Metal outgassing is controlled by magma water content and redox: deep saturation in vapor and minimal sulfide in arc basalts yields metal-rich vapor; shallow degassing and resorption of sulfides feeds the metal content of volcanic gas in ocean islands. We present a detailed study of the sulfide systematics of the products of the 2014-2015 Holuhraun basaltic fissure eruption (Bárðarbunga volcanic system, Iceland) to illustrate the interplay between late water and sulfur outgassing; sulfide saturation and breakdown; and metal partitioning into a vapor phase. Sulfide globules, representing quenched droplets of an immiscible sulfide liquid, are preserved within erupted tephra. Sulfide globules in rapidly quenched tephra are preserved within both matrix glass and as inclusions in crystals. The stereologically-corrected 3D size distribution of sulfide globules ranges from importance in supplying sulfur and metals to the atmosphere during eruption.

Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water.

Science.gov (United States)

Kato, Masashi; Kumasaka, Mayuko Y; Ohnuma, Shoko; Furuta, Akio; Kato, Yoko; Shekhar, Hossain U; Kojima, Michiyo; Koike, Yasuko; Dinh Thang, Nguyen; Ohgami, Nobutaka; Ly, Thuy Bich; Jia, Xiaofang; Yetti, Husna; Naito, Hisao; Ichihara, Gaku; Yajima, Ichiro

2013-01-01

Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L) and coexposure to barium (137 µg/L) and arsenic (225 µg/L). The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L) and barium (700 µg/L), but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium), in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to barium in humans and propose a novel remediation system.

Nano Transition Metal Sulfide Catalyst for Solvolysis Liquefaction of Soda Lignin

International Nuclear Information System (INIS)

Fei-Ling, P.; Chin-Hua, C.; Sarani Zakaria; Soon-Keong, N.; Tze-Khong, L.

2011-01-01

Solvolysis liquefaction of soda lignin in the presence of various transition metal sulfide catalysts was studied to investigate the catalyst effects on the oil and gas yields, conversion rate and higher heating value (HHV) of oil. Nano sized copper sulfide, iron sulfide and molybdenum sulfide were successfully synthesized via a simple hydrothermal method under reaction temperature 200 degree Celsius for 90 min. The addition of transition metal sulfide based catalysts (CuS, MoS 2 and FeS 2 ) enhanced both production of the oils and gas and the higher heating value (HHV) of oil products. A high oil and gas yields of 82.1 % and 2890 cm 3 was obtained with MoS 2 at 250 degree Celsius for 60 min. Elemental analyses for the oils revealed that the liquid products have much higher heating values than the crude soda lignin powder. (author)

Formation of nanocolloidal metacinnabar in mercury-DOM-sulfide systems

Science.gov (United States)

Gerbig, Chase A.; Kim, Christopher S.; Stegemeier, John P.; Ryan, Joseph N.; Aiken, George R.

2011-01-01

Direct determination of mercury (Hg) speciation in sulfide-containing environments is confounded by low mercury concentrations and poor analytical sensitivity. Here we report the results of experiments designed to assess mercury speciation at environmentally relevant ratios of mercury to dissolved organic matter (DOM) (i.e., structure (EXAFS) spectroscopy. Aqueous Hg(II) and a DOM isolate were equilibrated in the presence and absence of 100 μM total sulfide. In the absence of sulfide, mercury adsorption to the resin increased as the Hg:DOM ratio decreased and as the strength of Hg-DOM binding increased. EXAFS analysis indicated that in the absence of sulfide, mercury bonds with an average of 2.4 ± 0.2 sulfur atoms with a bond length typical of mercury-organic thiol ligands (2.35 Å). In the presence of sulfide, mercury showed greater affinity for the C18 resin, and its chromatographic behavior was independent of Hg:DOM ratio. EXAFS analysis showed mercury–sulfur bonds with a longer interatomic distance (2.51–2.53 Å) similar to the mercury–sulfur bond distance in metacinnabar (2.53 Å) regardless of the Hg:DOM ratio. For all samples containing sulfide, the sulfur coordination number was below the ideal four-coordinate structure of metacinnabar. At a low Hg:DOM ratio where strong binding DOM sites may control mercury speciation (1.9 nmol mg–1) mercury was coordinated by 2.3 ± 0.2 sulfur atoms, and the coordination number rose with increasing Hg:DOM ratio. The less-than-ideal coordination numbers indicate metacinnabar-like species on the nanometer scale, and the positive correlation between Hg:DOM ratio and sulfur coordination number suggests progressively increasing particle size or crystalline order with increasing abundance of mercury with respect to DOM. In DOM-containing sulfidic systems nanocolloidal metacinnabar-like species may form, and these species need to be considered when addressing mercury biogeochemistry.

Enhanced performance of denitrifying sulfide removal process under micro-aerobic condition.

Science.gov (United States)

Chen, Chuan; Ren, Nanqi; Wang, Aijie; Liu, Lihong; Lee, Duu-Jong

2010-07-15

The denitrifying sulfide removal (DSR) process with bio-granules comprising both heterotrophic and autotrophic denitrifiers can simultaneously convert nitrate, sulfide and acetate into di-nitrogen gas, elementary sulfur and carbon dioxide, respectively, at high loading rates. This study determines the reaction rate of sulfide oxidized into sulfur, as well as the reduction of nitrate to nitrite, would be enhanced under a micro-aerobic condition. The presence of limited oxygen mitigated the inhibition effects of sulfide on denitrifier activities, and enhanced the performance of DSR granules. The advantages and disadvantages of applying the micro-aerobic condition to the DSR process are discussed. 2010 Elsevier B.V. All rights reserved.

Three-dimensional, two-species magnetohydrodynamic studies of the early time behaviors of the Combined Release and Radiation Effects Satellite G2 barium release

International Nuclear Information System (INIS)

Xie, Lianghai; Li, Lei; Wang, Jingdong; Zhang, Yiteng

2014-01-01

We present a three-dimensional, two-species (Ba + and H + ) MHD model to study the early time behaviors of a barium release at about 1 R E like Combined Release and Radiation Effects Satellite G2, with emphasis placed on the three-dimensional evolution of the barium cloud and its effects on the ambient plasma environment. We find that the perturbations caused by the cloud are the combined results of the initial injection, the radial expansion, and the diamagnetic effect and propagate as fast MHD waves in the magnetosphere. In return, the transverse expansion and the cross-B motion of barium ions are constrained by the magnetic force, which lead to a field-aligned striation of ions and the decoupling of these ions from the neutrals. Our simulation shows the formation and collapse of the diamagnetic cavity in the barium cloud. The estimated time scale for the cavity evolution might be much shorter if photoionization time scale and field aligned expansion of barium ions are considered. In addition, our two species MHD simulation also finds the snowplow effect resulting from the momentum coupling between barium ions and background H + , which creates density hole and bumps in the background H + when barium ions expanding along the magnetic field lines

Study of precipitation processes of strontium and barium nitrates in mixtures of water-with dimethylformamide and dimethylsulfoxide

International Nuclear Information System (INIS)

Eliseeva, O.V.; Abakshin, V.A.; Barannikov, V.P.; Krestov, G.A.

1994-01-01

The investigation into phase equilibriums diagrams in the barium (strontium) nitrate-water-dimethylsulfoxide and barium nitrate-water dimethylformamide systems has been pursued at 298, 15 K for the estimation of outlook for use of mixed aqua-organic solvents during the production of mixture form high temperature superconductors by means of coprecipitation or crystallization. 4 refs., 3 figs., 2 tabs

Barium halide nanocrystals in fluorozirconate based glass ceramics for scintillation application

Energy Technology Data Exchange (ETDEWEB)

Selling, J.

2007-07-01

Europium (Eu)-activated barium halide nanocrystals in fluorozirconate based glass ceramics represent a promising class of Xray scintillators. The scintillation in these glass ceramics is mainly caused by the emission of divalent Eu incorporated in hexagonal BaCl{sub 2} nanocrystals which are formed in the glass matrix upon appropriate annealing. Experiments with cerium (Ce)-activated fluorozironate glass ceramics showed that Ce is an interesting alternative. In order to get a better understanding of the scintillation mechanism in Eu- or Ce-activated barium halide nanocrystals, an investigation of the processes in the corresponding bulk material is essential. The objective of this thesis is the investigation of undoped, Eu-, and Ce-doped barium halides by X-ray excited luminescence (XL), pulse height, and scintillation decay spectra. That will help to figure out which of these crystals has the most promising scintillation properties and would be the best nanoparticles for the glass ceramics. Furthermore, alternative dopants like samarium (Sm) and manganese (Mn) were also investigated. Besides the above-mentioned optical investigation electron paramagnetic resonance (EPR) and Moessbauer measurements were carried out in order to complete the picture of Eu-doped barium halides. The EPR data of Eu-doped BaI{sub 2} is anticipated to yield more information about the crystal field and crystal structure that will help to understand the charge carrier process during the scintillation process. The main focus of the Moessbauer investigations was set on the Eu-doped fluorochlorozirconate glass ceramics. The results of this investigation should help to improve the glass ceramics. The Eu{sup 2+}/Eu{sup 3+} ratio in the glass ceramics should be determined and optimize favor of the Eu{sup 2+}. We also want to distinguish between Eu{sup 2+} in the glass matrix and Eu{sup 2+} in the nanocrystals. For a better understanding of Moessbauer spectroscopy on Eu also measurements on Eu in a

Barium halide nanocrystals in fluorozirconate based glass ceramics for scintillation application

International Nuclear Information System (INIS)

Selling, J.

2007-01-01

Europium (Eu)-activated barium halide nanocrystals in fluorozirconate based glass ceramics represent a promising class of Xray scintillators. The scintillation in these glass ceramics is mainly caused by the emission of divalent Eu incorporated in hexagonal BaCl 2 nanocrystals which are formed in the glass matrix upon appropriate annealing. Experiments with cerium (Ce)-activated fluorozironate glass ceramics showed that Ce is an interesting alternative. In order to get a better understanding of the scintillation mechanism in Eu- or Ce-activated barium halide nanocrystals, an investigation of the processes in the corresponding bulk material is essential. The objective of this thesis is the investigation of undoped, Eu-, and Ce-doped barium halides by X-ray excited luminescence (XL), pulse height, and scintillation decay spectra. That will help to figure out which of these crystals has the most promising scintillation properties and would be the best nanoparticles for the glass ceramics. Furthermore, alternative dopants like samarium (Sm) and manganese (Mn) were also investigated. Besides the above-mentioned optical investigation electron paramagnetic resonance (EPR) and Moessbauer measurements were carried out in order to complete the picture of Eu-doped barium halides. The EPR data of Eu-doped BaI 2 is anticipated to yield more information about the crystal field and crystal structure that will help to understand the charge carrier process during the scintillation process. The main focus of the Moessbauer investigations was set on the Eu-doped fluorochlorozirconate glass ceramics. The results of this investigation should help to improve the glass ceramics. The Eu 2+ /Eu 3+ ratio in the glass ceramics should be determined and optimize favor of the Eu 2+ . We also want to distinguish between Eu 2+ in the glass matrix and Eu 2+ in the nanocrystals. For a better understanding of Moessbauer spectroscopy on Eu also measurements on Eu in a CaF 2 host lattice were carried

Passivation Of High-Temperature Superconductors

Science.gov (United States)

Vasquez, Richard P.

1991-01-01

Surfaces of high-temperature superconductors passivated with native iodides, sulfides, or sulfates formed by chemical treatments after superconductors grown. Passivating compounds nearly insoluble in and unreactive with water and protect underlying superconductors from effects of moisture. Layers of cuprous iodide and of barium sulfate grown. Other candidate passivating surface films: iodides and sulfides of bismuth, strontium, and thallium. Other proposed techniques for formation of passivating layers include deposition and gas-phase reaction.

Self-assembly of a tetrahedral 58-nuclear barium vanadium oxide cluster.

Science.gov (United States)

Kastner, Katharina; Puscher, Bianka; Streb, Carsten

2013-01-07

We report the synthesis and characterization of a molecular barium vanadium oxide cluster featuring high nuclearity and high symmetry. The tetrameric, 2.3 nm cluster H(5)[Ba(10)(NMP)(14)(H(2)O)(8)[V(12)O(33)](4)Br] is based on a bromide-centred, octahedral barium scaffold which is capped by four previously unknown [V(12)O(33)](6-) clusters in a tetrahedral fashion. The compound represents the largest polyoxovanadate-based heterometallic cluster known to date. The cluster is formed in organic solution and it is suggested that the bulky N-methyl-2-pyrrolidone (NMP) solvent ligands allow the isolation of this giant molecule and prevent further condensation to a solid-state metal oxide. The cluster is fully characterized using single-crystal XRD, elemental analysis, ESI mass spectrometry and other spectroscopic techniques.

Sulfidization of an aluminocobaltomolybdenum catalyst using the 35S radioisotope

International Nuclear Information System (INIS)

Isagulyants, G.V.; Greish, A.A.; Kogan, V.M.

1987-01-01

It has been established that in aluminocobaltomolybdenum catalyst sulfidized with elemental sulfur there are two types of sulfur, free and bound. The maximum amount of bound sulfur in ACM catalyst is 6.6 wt. %, which corresponds to practically complete sulfidation of the ACM catalyst. In the presence of hydrogen an equilibrium distribution of bound sulfur is achieved in a granule of ACM catalyst irrespective of the temperature of sulfidation. In a nitrogen atmosphere it is primarily the surface layers of the catalyst that are sulfured

Microbial selenium sulfide reduction for selenium recovery from wastewater

NARCIS (Netherlands)

Hageman, S.P.W.; Weijden, van der R.D.; Stams, A.J.M.; Cappellen, van P.; Buisman, C.J.N.

2017-01-01

Microbial reduction of selenium sulfide (SeS2) is a key step in a new treatment process to recover selenium from selenate and selenite streams. In this process, selenate is first reduced to selenite, and subsequently selenite is reduced by sulfide and precipitates from the solution as SeS2. The

Effect of mucolytic pretreatment on gastric mucosal coating with barium sulfate in the rat

International Nuclear Information System (INIS)

Lindgren, I.; Nevalainen, T.; Maeki, J.; Soederstroem, K.-O.

1980-01-01

Freshly prepared isolated rat stomachs were used to examine the adherence of barium sulfate particles to the mucosal surface by scanning electron microscopy. The stomachs were pretreated with sodium bicarbonate alone or in connection with N-acetyl-L-cysteine and then treated with barium sulfate specially designed for double contrast examination of the stomach. The best adhesion of the contrast medium was obtained when the mucosa was pretreated with both the alkaline and mucolytic agent indicating that, for the optimum adherence of the contrast medium, the mucosal surface must be as clean as possible. (Auth.)

Observation of potential barriers on barium strontium titanate PTCR ceramics by electrostatic force microscopy

International Nuclear Information System (INIS)

Manfredini, J.P.; Paulin Filho, P.I.; Gheno, S.M.

2011-01-01

A composition of PTCR ceramic based in barium titanate with isovalent replacement of part of barium by strontium using lanthanum and manganese as additives was investigated. The transition temperature, typical of these materials, was shifted below the room temperature by the presence of strontium, whose behavior was detected by tests of DC resistivity and impedance spectroscopy. The observation of potential barriers at grain boundaries was possible through the technique of electrostatic force microscopy (EFM). The results also showed the presence of space charges in regions inside grains, possibly at subgrain boundaries. (author)

Barium isotope fractionation during experimental formation of the double carbonate BaMn[CO3](2) at ambient temperature.

Science.gov (United States)

Böttcher, Michael E; Geprägs, Patrizia; Neubert, Nadja; von Allmen, Katja; Pretet, Chloé; Samankassou, Elias; Nägler, Thomas F

2012-09-01

In this study, we present the first experimental results for stable barium (Ba) isotope ((137)Ba/(134)Ba) fractionation during low-temperature formation of the anhydrous double carbonate BaMn[CO(3)](2). This investigation is part of an ongoing work on Ba fractionation in the natural barium cycle. Precipitation at a temperature of 21±1°C leads to an enrichment of the lighter Ba isotope described by an enrichment factor of-0.11±0.06‰ in the double carbonate than in an aqueous barium-manganese(II) chloride/sodium bicarbonate solution, which is within the range of previous reports for synthetic pure BaCO (3) (witherite) formation.

Study on the surface sulfidization behavior of smithsonite at high temperature

Science.gov (United States)

Lv, Jin-fang; Tong, Xiong; Zheng, Yong-xing; Xie, Xian; Wang, Cong-bing

2018-04-01

Surface sulfidization behavior of smithsonite at high temperature was investigated by X-ray powder diffractometer (XRD) along with thermodynamic calculation, X-ray photoelectron spectroscopy (XPS) and electron probe microanalysis (EPMA). The XRD and thermodynamic analyses indicated that the smithsonite was decomposed into zincite at high temperatures. After introducing a small amount of pyrite, artificial sulfides were formed at surface of the obtained zincite. The XPS analyses revealed that the sulfide species including zinc sulfide and zinc disulfide were generated at the zincite surface. The EPMA analyses demonstrated that the film of sulfides was unevenly distributed at the zincite surface. The average concentration of elemental sulfur at the sample surface increased with increasing of pyrite dosage. A suitable mole ratio of FeS2 to ZnCO3 for the surface thermal modification was determined to be about 0.3. These findings can provide theoretical support for improving the process during which the zinc recovery from refractory zinc oxide ores is achieved by xanthate flotation.

Spectral induced polarization and electrodic potential monitoring of microbially mediated iron sulfide transformations

Energy Technology Data Exchange (ETDEWEB)

Hubbard, Susan; Personna, Y.R.; Ntarlagiannis, D.; Slater, L.; Yee, N.; O' Brien, M.; Hubbard, S.

2008-02-15

Stimulated sulfate-reduction is a bioremediation technique utilized for the sequestration of heavy metals in the subsurface.We performed laboratory column experiments to investigate the geoelectrical response of iron sulfide transformations by Desulfo vibriovulgaris. Two geoelectrical methods, (1) spectral induced polarization (SIP), and (2) electrodic potential measurements, were investigated. Aqueous geochemistry (sulfate, lactate, sulfide, and acetate), observations of precipitates (identified from electron microscopy as iron sulfide), and electrodic potentials on bisulfide ion (HS) sensitive silver-silver chloride (Ag-AgCl) electrodes (630 mV) were diagnostic of induced transitions between an aerobic iron sulfide forming conditions and aerobic conditions promoting iron sulfide dissolution. The SIP data showed 10m rad anomalies during iron sulfide mineralization accompanying microbial activity under an anaerobic transition. These anomalies disappeared during iron sulfide dissolution under the subsequent aerobic transition. SIP model parameters based on a Cole-Cole relaxation model of the polarization at the mineral-fluid interface were converted to (1) estimated biomineral surface area to pore volume (Sp), and (2) an equivalent polarizable sphere diameter (d) controlling the relaxation time. The temporal variation in these model parameters is consistent with filling and emptying of pores by iron sulfide biofilms, as the system transitions between anaerobic (pore filling) and aerobic (pore emptying) conditions. The results suggest that combined SIP and electrodic potential measurements might be used to monitor spatiotemporal variability in microbial iron sulfide transformations in the field.

Toxicity of sulfide to early life stages of wild rice (Zizania palustris).

Science.gov (United States)

Fort, Douglas J; Todhunter, Kevin; Fort, Troy D; Mathis, Michael B; Walker, Rachel; Hansel, Mike; Hall, Scott; Richards, Robin; Anderson, Kurt

2017-08-01

The sensitivity of wild rice (Zizania palustris) to sulfide is not well understood. Because sulfate in surface waters is reduced to sulfide by anaerobic bacteria in sediments and historical information indicated that 10 mg/L sulfate in Minnesota (USA) surface water reduced Z. palustris abundance, the Minnesota Pollution Control Agency established 10 mg/L sulfate as a water quality criterion in 1973. A 21-d daily-renewal hydroponic study was conducted to evaluate sulfide toxicity to wild rice and the potential mitigation of sulfide toxicity by iron (Fe). The hydroponic design used hypoxic test media for seed and root exposure and aerobic headspace for the vegetative portion of the plant. Test concentrations were 0.3, 1.6, 3.1, 7.8, and 12.5 mg/L sulfide in test media with 0.8, 2.8, and 10.8 mg/L total Fe used to evaluate the impact of iron on sulfide toxicity. Visual assessments (i.e., no plants harvested) of seed activation, mesocotyl emergence, seedling survival, and phytoxicity were conducted 10 d after dark-phase exposure. Each treatment was also evaluated for time to 30% emergence (ET30), total plant biomass, root and shoot lengths, and signs of phytotoxicity at study conclusion (21 d). The results indicate that exposure of developing wild rice to sulfide at ≥3.1 mg sulfide/L in the presence of 0.8 mg/L Fe reduced mesocotyl emergence. Sulfide toxicity was mitigated by the addition of Fe at 2.8 mg/L and 10.8 mg/L relative to the control value of 0.8 mg Fe/L, demonstrating the importance of iron in mitigating sulfide toxicity to wild rice. Ultimately, determination of site-specific sulfate criteria taking into account factors that alter toxicity, including sediment Fe and organic carbon, are necessary. Environ Toxicol Chem 2017;36:2217-2226. © 2017 SETAC. © 2017 SETAC.

Sulfide phase in the Fe-Ti-S and Fe-C-Ti-S alloys

International Nuclear Information System (INIS)

Malinochka, Ya.N.; Balakina, N.A.; Shmelev, Yu.S.

1976-01-01

The nature of the sulfide phases in Fe-Ti-S and Fe-C-Ti-S alloys was studied. The carbide and the sulfide phase were identified the aid of X-ray spectral microanalysis. It was established that for a small content of titanium and sulfur in ternary Fe-Ti-S alloys the solidification of the γ-solution on the boundaries of dendritic branches is accompanied, along with the precipitation of a sulfide rich in iron of the (Fe, Ti) S type where a small quantity of titanium is dissolved, by the formation of a titanium-bearing sulfide eutectic γ + TiS. The amount of the sulfide eutectic increases with the contents of titanium and sulfur until a purely eutectic alloy is formed. Both carbides and sulfides may be formed in the solidification of quaternary alloys Fe-C-Ti-S

Preparation and characterization of amorphous manganese sulfide thin films by SILAR method

International Nuclear Information System (INIS)

Pathan, H.M.; Kale, S.S.; Lokhande, C.D.; Han, Sung-Hwan; Joo, Oh-Shim

2007-01-01

Manganese sulfide thin films were deposited by a simple and inexpensive successive ionic layer adsorption and reaction (SILAR) method using manganese acetate as a manganese and sodium sulfide as sulfide ion sources, respectively. Manganese sulfide films were characterized for their structural, surface morphological and optical properties by means of X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis and optical absorption measurement techniques. The as-deposited film on glass substrate was amorphous. The optical band gap of the film was found to be thickness dependent. As thickness increases optical band gap was found to be increase. The water angle contact was found to be 34 o , suggesting hydrophilic nature of manganese sulfide thin films. The presence of Mn and S in thin film was confirmed by energy dispersive X-ray analysis

76 FR 64022 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

Science.gov (United States)

2011-10-17

... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide. SUMMARY: EPA is announcing... (EPCRA) section 313 toxic chemical release reporting requirements for hydrogen sulfide (Chemical...

Dynamics of a barium release in the magnetospheric tail

Science.gov (United States)

Mende, S. B.; Swenson, G. R.; Geller, S. P.; Doolittle, J. H.; Haerendel, G.

1989-01-01

The late time behavior of the May 13, 1985 magnetotail barium cloud is examined. The bulk dynamics of the cloud are studied based on triangulated data and data from Fabry-Perot Doppler velocity measurements. The changes in cloud morphology in relation to the in situ measurements made by the Ion Release Module satellite are discussed.

Comparison of Barium and Arsenic Concentrations in Well Drinking Water and in Human Body Samples and a Novel Remediation System for These Elements in Well Drinking Water.

Directory of Open Access Journals (Sweden)

Masashi Kato

Full Text Available Health risk for well drinking water is a worldwide problem. Our recent studies showed increased toxicity by exposure to barium alone (≤700 µg/L and coexposure to barium (137 µg/L and arsenic (225 µg/L. The present edition of WHO health-based guidelines for drinking water revised in 2011 has maintained the values of arsenic (10 µg/L and barium (700 µg/L, but not elements such as manganese, iron and zinc. Nevertheless, there have been very few studies on barium in drinking water and human samples. This study showed significant correlations between levels of arsenic and barium, but not its homologous elements (magnesium, calcium and strontium, in urine, toenail and hair samples obtained from residents of Jessore, Bangladesh. Significant correlation between levels of arsenic and barium in well drinking water and levels in human urine, toenail and hair samples were also observed. Based on these results, a high-performance and low-cost adsorbent composed of a hydrotalcite-like compound for barium and arsenic was developed. The adsorbent reduced levels of barium and arsenic from well water in Bangladesh and Vietnam to <7 µg/L within 1 min. Thus, we have showed levels of arsenic and barium in humans and propose a novel remediation system.

High resolution studies of barium Rydberg states

International Nuclear Information System (INIS)

Eliel, E.R.

1982-01-01

The subtle structure of Rydberg states of barium with orbital angular momentum 0, 1, 2 and 3 is investigated. Some aspects of atomic theory for a configuration with two valence electrons are reviewed. The Multi Channel Quantum Defect Theory (MQDT) is concisely introduced as a convenient way to describe interactions between Rydberg series. Three high-resolution UV studies are presented. The first two, presenting results on a transition in indium and europium serve as an illustration of the frequency doubling technique. The third study is of hyperfine structure and isotope shifts in low-lying p states in Sr and Ba. An extensive study of the 6snp and 6snf Rydberg states of barium is presented with particular emphasis on the 6snf states. It is shown that the level structure cannot be fully explained with the model introduced earlier. Rather an effective two-body spin-orbit interaction has to be introduced to account for the observed splittings, illustrating that high resolution studies on Rydberg states offer an unique opportunity to determine the importance of such effects. Finally, the 6sns and 6snd series are considered. The hyperfine induced isotope shift in the simple excitation spectra to 6sns 1 S 0 is discussed and attention is paid to series perturbers. It is shown that level mixing parameters can easily be extracted from the experimental data. (Auth.)

76 FR 69136 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

Science.gov (United States)

2011-11-08

... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide; Correction. SUMMARY: The... Administrative Stay of the reporting requirements for hydrogen sulfide. The Office of the Federal Register...

Enrichment and immobilization of sulfide removal microbiota applied for environmental biological remediation of aquaculture area

International Nuclear Information System (INIS)

Zhao, Yang-Guo; Zheng, Yu; Tian, Weijun; Bai, Jie; Feng, Gong; Guo, Liang; Gao, Mengchun

2016-01-01

To remove sulfide in the deteriorating aquaculture sediment and water, sulfide-oxidizing microbiota was enriched from Jiaozhou Bay, China, by using sulfide-rich medium. Composition and structure of microbial communities in the enrichments were investigated by 16S rDNA molecular biotechniques. Results showed that microbial community structure continuously shifted and the abundance of sulfate reducing bacteria, i.e., Desulfobacterium, Desulfococcus and Desulfobacca apparently declined. Several halophile genera, Vibrio, Marinobacter, Pseudomonas, Prochlorococcus, Pediococcus and Thiobacillus predominated finally in the microbiota. The enriched microbiota was capable of removing a maximum of 1000 mg/L sulfide within 12 h with 10% inoculum at pH 7.0, 20–30 °C. After immobilized, the microbiota presented excellent resistance to impact and could completely remove 600 mg/L sulfide in 12 h. Moreover, the immobilized microbiota recovered well even recycled for five times. In conclusion, the immobilized sulfide-removing microbiota showed a quite promising application for biological restoring of sulfide-rich aquaculture environment. - Highlights: • A sulfide-oxidizing microbiota successfully enriched from aquaculture sediment. • Microbiota dominated by Vibrio, Marinobacter, Pseudomonas and Thiobacillus spp. • Sulfide-oxidizing microbiota removed sulfide at an average rate of 100 mg/(L·h). • Immobilized microbiota removed over 85% of sulfide even recycled for five times.