Study of the bismuth oxide concentration required to provide Portland cement with adequate radiopacity for endodontic use.

Science.gov (United States)

Bueno, Carlos Eduardo da Silveira; Zeferino, Eduardo Gregatto; Manhães, Luiz Roberto Coutinho; Rocha, Daniel Guimarães Pedro; Cunha, Rodrigo Sanches; De Martin, Alexandre Sigrist

2009-01-01

The purpose of this study was to determine the ideal concentration of bismuth oxide in white Portland cement to provide it with sufficient radiopacity for use as an endodontic material (ADA specification #57). 2-mm thick standardized test specimens of white MTA and of white Portland cement, as controls, and of white Portland cement with the experimental addition of 5%, 10%, 15%, 20%, 25% or 30% of bismuth oxide were radiographed and compared with various thicknesses of pure aluminum, using optic density to determine the observed grayscale levels of radiopacity in a scale ranging from 0 to 255. The data was submitted to ANOVA (pcement with 0%, 5%, 10%, 15%, 20%, 25% and 30% of bismuth oxide presented mean readings of 63.3, 95.7, 110.7, 142.7, 151.3, 161.0 and 180.0 respectively. MTA presented a mean reading of 157.3. The readings of MTA and white Portland cement with 15% bismuth oxide did not differ significantly from the reading observed for a thickness of 4 mm of aluminum (145.3), which is considered ideal for a test specimen by ADA specification #57 (2 mm above the thickness of the test specimen). White MTA and white Portland cement with 15% bismuth oxide presented the radiopacity required for an endodontic cement.

Preterm delivery among people living around Portland cement plants

International Nuclear Information System (INIS)

Yang, C.-Y.; Chang, C.-C.; Tsai, S.-S.; Huang, H.-Y.; Ho, C.-K.; Wu, T.-N.; Sung, F.-C.

2003-01-01

The Portland cement industry is the main source of particulate air pollution in Kaohsiung city. Data in this study concern outdoor air pollution and the health of individuals living in communities in close proximity to Portland cement plants. The prevalence of delivery of preterm birth infants as significantly higher in mothers living within 0-2 km of a Portland cement plant than in mothers living within 2-4 km. After controlling for several possible confounders (including maternal age, season, marital status, maternal education, and infant sex), the adjusted odds ratio was 1.30 (95% I=1.09-1.54) for the delivery of preterm infants for mothers living close to he Portland cement plants, chosen at the start to be from 0 to 2 km. These data provide further support for the hypothesis that air pollution can affect he outcome of pregnancy

Basalt waste added to Portland cement

Directory of Open Access Journals (Sweden)

Thiago Melanda Mendes

2016-08-01

Full Text Available Portland cement is widely used as a building material and more than 4.3 billion tons were produced in 2014, with increasing environmental impacts by this industry, mainly through CO2 emissions and consumption of non-removable raw materials. Several by-products have been used as raw materials or fuels to reduce environmental impacts. Basaltic waste collected by filters was employed as a mineral mixture to Portland cement and two fractions were tested. The compression strength of mortars was measured after 7 days and Scanning Electron Microscopy (SEM and Electron Diffraction Scattering (EDS were carried out on Portland cement paste with the basaltic residue. Gains in compression strength were observed for mixtures containing 2.5 wt.% of basaltic residue. Hydration products observed on surface of basaltic particles show the nucleation effect of mineral mixtures. Clinker substitution by mineral mixtures reduces CO2 emission per ton of Portland cement.

Immediate and delayed solubility of mineral trioxide aggregate and Portland cement

Directory of Open Access Journals (Sweden)

Augusto Bodanezi

2008-04-01

Full Text Available This study investigated the solubility of mineral trioxide aggregate (MTA and Portland cement since its mixture until 672 hours, by means of two complimentary methods. Metal ring molds filled with the cements were covered with distilled water and, at each experimental time (3, 24, 72, 168, 336 and 672 hours, were weighed as soon as the plates in which the samples have been placed. Empty rings served as the control group (n=8. Mean weight gain and loss was determined and analyzed statistically by two-way ANOVA and Tukey's test for all pairwise comparisons. Only Portland cement showed less than 3% weight loss through 24 hours. Detached MTA residues were heavier than those of Portland cement over the 3 to 168 hours. The weight of MTA rings increased more than that of Portland rings within 672 hours (p=0.05. The findings of the present study indicate that, in an aqueous environment MTA is more soluble than Portland cement and exceeds the maximum weight loss considered acceptable by ISO 6876 standard (2001.

Immediate and delayed solubility of mineral trioxide aggregate and Portland cement.

Science.gov (United States)

Bodanezi, Augusto; Carvalho, Nara; Silva, Daniela; Bernardineli, Norberti; Bramante, Clovis Monteiro; Garcia, Roberto Brandão; de Moraes, Ivaldo Gomes

2008-01-01

This study investigated the solubility of mineral trioxide aggregate (MTA) and Portland cement since its mixture until 672 hours, by means of two complimentary methods. Metal ring molds filled with the cements were covered with distilled water and, at each experimental time (3, 24, 72, 168, 336 and 672 hours), were weighed as soon as the plates in which the samples have been placed. Empty rings served as the control group (n=8). Mean weight gain and loss was determined and analyzed statistically by two-way ANOVA and Tukey's test for all pairwise comparisons. Only Portland cement showed less than 3% weight loss through 24 hours. Detached MTA residues were heavier than those of Portland cement over the 3 to 168 hours. The weight of MTA rings increased more than that of Portland rings within 672 hours (p=0.05). The findings of the present study indicate that, in an aqueous environment MTA is more soluble than Portland cement and exceeds the maximum weight loss considered acceptable by ISO 6876 standard (2001).

Comparative Study of Portland Cement-based and Zeolite-based Concretes in Terms of Hexavalent Chromium Leaching

Directory of Open Access Journals (Sweden)

Oravec Jozef

2016-12-01

Full Text Available The paper presents the results of the leaching study of Portland cement-based and zeolite-based concretes regarding water soluble hexavalent chromium. Three leaching water media (distilled water, rain water, and Britton-Robinson buffer of various pH values were under investigation. The correlation between pH and leached-out concentrations of chromium was not confirmed. The content of hexavalent water-soluble chromium in leachates of zeolite-based concretes was found to be higher than that in leachates of Portland cement-based samples.

Recycled materials in Portland cement concrete

Science.gov (United States)

2000-06-01

This report pertains to a comprehensive study involving the use of recycled materials in Portland cement concrete. Three different materials were studied including crushed glass (CG), street sweepings (SS), and recycled concrete (RC). Blast furnace s...

Energy costs and Portland water supply system

Energy Technology Data Exchange (ETDEWEB)

Elliott, W.M.; Hawley, R.P.

1981-10-01

The changing role of electrical energy on the Portland, Oregon, municipal-water-supply system is presented. Portland's actions in energy conservation include improved operating procedures, pump modifications, and modifications to the water system to eliminate pumping. Portland is implementing a small hydroelectric project at existing water-supply dams to produce an additional source of power for the area. Special precautions in construction and operation are necessary to protect the high quality of the water supply. 2 references, 7 figures.

Interim restorations.

Science.gov (United States)

Gratton, David G; Aquilino, Steven A

2004-04-01

Interim restorations are a critical component of fixed prosthodontic treatment, biologically and biomechanically. Interim restoration serves an important diagnostic role as a functional and esthetic try-in and as a blueprint for the design of the definitive prosthesis. When selecting materials for any interim restoration, clinicians must consider physical properties, handling properties, patient acceptance, and material cost. Although no single material meets all the requirements and material classification alone of a given product is not a predictor of clinical performance, bis-acryl materials are typically best suited to single-unit restorations, and poly(methylmethacrylate) interim materials are generally ideal for multi-unit, complex, long-term, interim fixed prostheses. As with most dental procedures, the technique used for fabrication has a greater effect on the final result than the specific material chosen.

Nuevos conglomerantes complementarios del cemento portland

OpenAIRE

Argiz, Cristina; Menéndez, Esperanza; Moragues, Amparo; Sanjuan-Barbudo, Miguel

2012-01-01

El desarrollo de nuevos conglomerantes complementarios al cemento portland se presenta como una alternativa que permitirá reciclar residuos, entre otros posibles beneficios. Estos nuevos materiales difícilmente podrán competir con el cemento portland ya que sus aplicaciones son limitadas y su coste, en general, más elevado.

Plutonium Finishing Plant. Interim plutonium stabilization engineering study

Energy Technology Data Exchange (ETDEWEB)

Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J. [Pacific Northwest Lab., Richland, WA (United States); Nass, R. [Nuclear Fuel Services, Inc. (United States)

1995-08-01

This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage.

Plutonium Finishing Plant. Interim plutonium stabilization engineering study

International Nuclear Information System (INIS)

Sevigny, G.J.; Gallucci, R.H.; Garrett, S.M.K.; Geeting, J.G.H.; Goheen, R.S.; Molton, P.M.; Templeton, K.J.; Villegas, A.J.; Nass, R.

1995-08-01

This report provides the results of an engineering study that evaluated the available technologies for stabilizing the plutonium stored at the Plutonium Finishing Plant located at the hanford Site in southeastern Washington. Further processing of the plutonium may be required to prepare the plutonium for interim (<50 years) storage. Specifically this document provides the current plutonium inventory and characterization, the initial screening process, and the process descriptions and flowsheets of the technologies that passed the initial screening. The conclusions and recommendations also are provided. The information contained in this report will be used to assist in the preparation of the environmental impact statement and to help decision makers determine which is the preferred technology to process the plutonium for interim storage

International validation study for interim PET in ABVD-treated, advanced-stage hodgkin lymphoma

DEFF Research Database (Denmark)

Biggi, Alberto; Gallamini, Andrea; Chauvie, Stephane

2013-01-01

At present, there are no standard criteria that have been validated for interim PET reporting in lymphoma. In 2009, an international workshop attended by hematologists and nuclear medicine experts in Deauville, France, proposed to develop simple and reproducible rules for interim PET reporting...... in lymphoma. Accordingly, an international validation study was undertaken with the primary aim of validating the prognostic role of interim PET using the Deauville 5-point score to evaluate images and with the secondary aim of measuring concordance rates among reviewers using the same 5-point score...

Biocompatibility of Portland cement combined with different radiopacifying agents.

Science.gov (United States)

Lourenço Neto, Natalino; Marques, Nádia C T; Fernandes, Ana Paula; Rodini, Camila O; Duarte, Marco A H; Lima, Marta C; Machado, Maria A A M; Abdo, Ruy C C; Oliveira, Thais M

2014-03-01

The aim of this study was to evaluate the response of rat subcutaneous tissue to Portland cement combined with two different radiopacifying agents, iodoform (CHI3) and zirconium oxide (ZrO2). These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Wistar rats for 7 and 15 days. The specimens were then stained with hematoxylin and eosin, and inflammatory reaction parameters were evaluated by light microscopy. The intensity of the inflammatory response to the sealants was analyzed by two blind calibrated observers throughout the experimental period. Histological analysis showed that all the materials caused a moderated inflammatory reaction at 7 days, which then diminished with time. At 15 days, the inflammatory reaction was almost absent, and fibroblasts and collagen fibers were observed indicating normal tissue healing. The degrees of the inflammatory reaction on different days throughout the experimental period were compared using the non-parametric Kruskal-Wallis test. Statistical analysis demonstrated no significant differences amongst the groups, and Portland cement associated with radiopacifying agents gave satisfactory results. Therefore, Portland cement used in combination with radiopacifying agents can be considered a biocompatible material. Although our results are very encouraging, further studies are needed in order to establish safe clinical indications for Portland cement combined with radiopacifying agents.

Poet Portland Approval

Science.gov (United States)

This update August 9, 2016 letter from EPA approves the petition, with modifications, from Poet Biorefining-Portland, LLC, regarding non-grandfathered ethanol produced through a dry mill process, qualifying under the Clean Air Act for renewable fuel

The Arabic Version of the Mayo-Portland Adaptability Inventory 4: A Validation Study

Science.gov (United States)

Hamed, Razan; Tariah, Hashem Abu; Malkawi, Somaya; Holm, Margo B.

2012-01-01

The Mayo-Portland Adaptability Inventory 4 (MPAI-4) is a valid and reliable assessment tool to detect clinical impairments in patients with acquired brain injury. The tool is widely used by rehabilitation therapists worldwide, given its good psychometric properties and its availability in several languages. The purpose of this study was to…

INFLUENCE OF SUBSTITUTION OF ORDINARY PORTLAND CEMENT BY SILICA FUME ON THE HYDRATION OF SLAG-PORTLAND CEMENT PASTES

Directory of Open Access Journals (Sweden)

E.A. El-Alfi

2011-06-01

Full Text Available Effect of gradual substitution of ordinary Portland cement by a few percent of silica fume (0.0, 2.5, 5.0 and 7.5 wt.% on the hydration properties of slag-Portland cement pastes up to 12 months was investigated. The results show that the composite cement pastes containing silica fume give the higher physico-mechanical properties than that of the slag-Portland cement. Also, the XRD results reveal that the peak of Ca(OH2 shows higher intensity in the sample without silica fume and completely disappears in the sample containing 7.5 wt.% silica fume content. Also, the intensity peaks of C4AH13 sharply increase with silica fume content.

40 CFR 81.51 - Portland Interstate Air Quality Control Region.

Science.gov (United States)

2010-07-01

... Quality Control Regions § 81.51 Portland Interstate Air Quality Control Region. The Portland Interstate Air Quality Control Region (Oregon-Washington) has been revised to consist of the territorial area... Portland Interstate Air Quality Control Region (Oregon-Washington) will be referred to by Washington...

Production of portland cement using Moroccan oil shale and comparative study between conventional cement plant and cement plant using oil shale

International Nuclear Information System (INIS)

Doumbouya, M.; Kacemi, K.E.; Kitane, S.

2012-01-01

Like the use of coal ash from power plants as an addition to cement, oil shale are used for cement production on an industrial scale in Estonia, China, USA and Germany. Oil shale can be utilized in manufacturing the cement. In addition to the utilization of these by-products after combustion, it can also reduce the required temperature for the clinkering reactions during the production of Portland clinker. We performed a study on the Moroccan oil shale to maximize the use of oil shale ash in the manufacturing of Portland cement. We found that Moroccan oil shale ash can be used up to 30% with 70% Portland clinker without altering its principle properties. The corresponding temperature required to generate the required liquid for the clinkering reactions as well as the essential ingredients for clinker was found to be around 850 to 1000 deg. C. The operating temperatures for this optimized blend ratio were found to 1000 deg. C. The resulting Portland clinker from this ratio will need further testing in accordance with international standards for Portland cement to examine properties like strength and setting time. (author)

Study of irradiation damage by fast neutrons in samples of Portland cement

International Nuclear Information System (INIS)

Lucki, G.; Rosa Junior, A.A.

1984-01-01

The effect of neutron irradiation in samples of Portland cement was evaluated, using the resonance frequency method and pulse velocity of ultra-sound techniques. The samples were divided in three groups: 1) monitoring samples; 2) samples submitted to gamma heating; 3) Irradiated samples. In the sample preparation, it was used the Portland Santa Rita CP 320 cement, and water-cement rate of 0.40 l/Kg. The irradiation was done in the research reactor IEA-R1, at IPEN - CNEN/SP, with an integrated flux of 7.2 x 10 18 n/cm 2 (E approx. 1 MeV). Some damage were detected, due to the neutron flux, and by the thermal effect of gamma heating. (E.G.) [pt

Effect of mineral trioxide aggregates and Portland cements on inflammatory cells.

Science.gov (United States)

Shahi, Shahriar; Rahimi, Saeed; Yavari, Hamid Reza; Mokhtari, Hadi; Roshangar, Leila; Abasi, Mehran Mesgary; Sattari, Sahar; Abdolrahimi, Majid

2010-05-01

Recently, some studies have compared mineral trioxide aggregate (MTA) with Portland cements, concluding that the principal ingredients of Portland cements are similar to those of MTA. The purpose of the present study was to evaluate the effect of gray MTA, white MTA, and gray and white Portland cements on inflammatory cells in rats. Fresh mixtures mixed with distilled water were placed in polyethylene tubes, which were implanted in the dorsal subcutaneous connective tissue of 60 Sprague-Dawley rats along with empty tubes as controls. Tissue specimens were collected after the rats were sacrificed after 7, 15, 30, 60, and 90 days. The specimens were fixed, stained, processed, and histologically evaluated under a light microscope. Inflammatory reactions were classified as grade 0: without inflammatory cells, grade I: sporadic infiltration of inflammatory cells, grade II: moderate infiltration (125 cells). Data were analyzed with the nonparametric (two factor) analysis of variance and Kruskal-Wallis H-test. All the groups showed grade III inflammation after 7 and 15 days; there was a decrease in the inflammatory process after 30, 60, and 90 days. After 90 days, gray MTA, white MTA, and control groups had grade 0 inflammatory process, but gray Portland cement and white Portland cement groups showed grade 0 to grade I inflammatory processes. MTAs were more biocompatible; however, more studies are required. Copyright (c) 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Microstructure and durability of Portland cement-carbon nanotube composites

OpenAIRE

MacLeod, Alastair James Neil

2017-01-01

The incorporation of carbon nanotubes (CNTs), fibres with diameters less than 100 nanometres that exhibit a tensile strength in excess of ten times greater than steel, into Portland cement (OPC) is a relatively novel, yet promising, development for next-generation construction materials exhibiting enhanced strength and ductility, even multifunctionality. When added to Portland cement, creating a Portland cement-CNT nanocomposite material (OPC-CNT), CNTs promote the nucleation of the princi...

The existence state of uranium(VI) in portland cement matrix material immobilization body

International Nuclear Information System (INIS)

Tan Hongbin; Li Yuxiang

2005-01-01

The basis of Portland cement material reaction with uranium, the corrosion of uranium minerals in nature and the state of study on immobilization of uranium by Portland cement matrix material are introduced, and some considerations are presented. (authors)

Thermophysical properties of blends from Portland and sulfoaluminate-belite cements

International Nuclear Information System (INIS)

Mojumdar, S.C.; Janotka, I.

2002-01-01

The behavior of mortars with blends consisting of sulfoaluminate-belite cements and ordinary Portland cement made with cement to sand ratio of 1:3 by weight and w/c = 0.5 maintained for 90 days at 20 0 C either at 60% relative humidity - dry air or 100% relative humidity - wet air. The results show insufficient character of hydraulic activity of sulfoaluminate-belite cements. Their quality has been improved. The replacement of 15 wt % of sulfoaluminate-belite cement by ordinary Portland cement influences strength positively and elasticity modulus values as well as hydrated phases and pore structure development of sulfoaluminate-belite/ordinary Portland cement blends relative to pure sulfoaluminate-belite cement systems. The above statements confirm the possible making technologies, when improvements in sulfoaluminate-belite cements quality will be achieved. One would then anticipate the competition in usages between sulfoaluminate-belite/ordinary Portland cement and blast furnace-slag Portland cement systems in the practice. It is important to consider because sulfoaluminate-belite cements are of great advantage from the viewpoint of energy savings and quantity of CO 2 released during their production. Thermal characteristics of the samples were studied by thermogravimetry and differential thermal analysis from room temperature to 1000 0 C in air atmosphere. Generally, four significant temperature regions on thermogravimetry curves with the respective differential thermal analysis peak temperature for all types of samples are observed (Authors)

Flow properties of MK-based geopolymer pastes. A comparative study with standard Portland cement pastes.

Science.gov (United States)

Favier, Aurélie; Hot, Julie; Habert, Guillaume; Roussel, Nicolas; d'Espinose de Lacaillerie, Jean-Baptiste

2014-02-28

Geopolymers are presented in many studies as alternatives to ordinary Portland cement. Previous studies have focused on their chemical and mechanical properties, their microstructures and their potential applications, but very few have focussed on their rheological behaviour. Our work highlights the fundamental differences in the flow properties, which exist between geopolymers made from metakaolin and Ordinary Portland Cement (OPC). We show that colloidal interactions between metakaolin particles are negligible and that hydrodynamic effects control the rheological behaviour. Metakaolin-based geopolymers can then be described as Newtonian fluids with the viscosity controlled mainly by the high viscosity of the suspending alkaline silicate solution and not by the contribution of direct contacts between metakaolin grains. This fundamental difference between geopolymers and OPC implies that developments made in cement technology to improve rheological behaviour such as plasticizers will not be efficient for geopolymers and that new research directions need to be explored.

76 FR 28315 - Security Zone; Portland Rose Festival on Willamette River

Science.gov (United States)

2011-05-17

... Zone; Portland Rose Festival on Willamette River AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the Portland Rose Festival Security Zone in... River during the Portland Rose festival. During the enforcement period, no person or vessel may enter or...

Experimental study of chloride diffusivity in unsaturated ordinary Portland cement mortar

NARCIS (Netherlands)

Zhang, Y.; Ye, G.; Santhanam, M.

2017-01-01

Experiments are carried out to investigate the chloride diffusivity in partially saturated ordinary Portland cement mortars with water-to-cement (w/c) ratios of 0.4, 0.5 and 0.6. Based on resistivity measurement and Nernst-Einstein equation, the chloride diffusivities of cement mortars at various

Interim storage study report

Energy Technology Data Exchange (ETDEWEB)

Rawlins, J.K.

1998-02-01

High-level radioactive waste (HLW) stored at the Idaho Chemical Processing Plant (ICPP) in the form of calcine and liquid and liquid sodium-bearing waste (SBW) will be processed to provide a stable waste form and prepare the waste to be transported to a permanent repository. Because a permanent repository will not be available when the waste is processed, the waste must be stored at ICPP in an Interim Storage Facility (ISF). This report documents consideration of an ISF for each of the waste processing options under consideration.

Synthesis of pure Portland cement phases

DEFF Research Database (Denmark)

Wesselsky, Andreas; Jensen, Ole Mejlhede

2009-01-01

Pure phases commonly found in Portland cement clinkers are often used to test cement hydration behaviour in simplified experimental conditions. The synthesis of these phases is covered in this paper, starting with a description of phase relations and possible polymorphs of the four main phases...... in Portland cement, i.e. tricalcium silicate, dicalcium silicate, tricalcium aluminate and tetracalcium alumino ferrite. Details of the The process of solid state synthesis are is described in general including practical advice on equipment and techniques. Finally In addition, some exemplary mix compositions...

Decision on performing interim analysis for comparative clinical trials.

Science.gov (United States)

Pak, Kyongsun; Jacobus, Susanna; Uno, Hajime

2017-09-01

In randomized-controlled trials, interim analyses are often planned for possible early trial termination to claim superiority or futility of a new therapy. While unblinding is necessary to conduct the formal interim analysis in blinded studies, blinded data also have information about the potential treatment difference between the groups. We developed a blinded data monitoring tool that enables investigators to predict whether they observe such an unblinded interim analysis results that supports early termination of the trial. Investigators may skip some of the planned interim analyses if an early termination is unlikely. We specifically focused on blinded, randomized-controlled studies to compare binary endpoints of a new treatment with a control. Assuming one interim analysis is planned for early termination for superiority or futility, we conducted extensive simulation studies to assess the impact of the implementation of our tool on the size, power, expected number of interim analyses, and bias in the treatment effect. The numerical study showed the proposed monitoring tool does not affect size or power, but dramatically reduces the expected number of interim analyses when the effect of the treatment difference is small. The tool serves as a useful reference when interpreting the summary of the blinded data throughout the course of the trial, without losing integrity of the study. This tool could potentially save the study resources and budget by avoiding unnecessary interim analyses.

Formula of Moulding Sand, Bentonite and Portland Cement toImprove The Quality of Al-Si Cast Alloy

OpenAIRE

Andoko Andoko; Poppy Puspitasari; Avita Ayu Permanasari; Didin Zakaria Lubis

2017-01-01

A binder is any material used to strengthen the bonding of moulding sand grains. The primary function of the binder is to hold the moulding sand and other materialstogether to produce high-quality casts. In this study, there were four binder compositions being tested, i.e. 5% bentonite + 5% Portland cement, 4% bentonite + 6% Portland cement, 6% bentonite + 4% Portland cement, and 7% bentonite + 3% Portland cement. Each specimen was measured for its compressive strength, shear strength, tensil...

Radiopacity evaluation of Portland and MTA-based cements by digital radiographic system.

Science.gov (United States)

Borges, Alvaro Henrique; Pedro, Fabio Luiz Miranda; Semanoff-Segundo, Alex; Miranda, Carlos Eduardo Saraiva; Pécora, Jesus Djalma; Cruz Filho, Antônio Miranda

2011-01-01

The aim of the present study was to evaluate the radiopacity of Portland and MTA-based cements using the Digora TM digital radiographic system. The performed tests followed specification number 57 from the American National Standard Institute/American Dental Association (2000) for endodontic sealing materials. The materials were placed in 5 acrylic plates, especially designed for this experiment, along with a graduated aluminum stepwedge varying from 1 to 10 mm in thickness. The set was radiographed at a 30 cm focus-object distance and with 0.2 s exposure time. After the radiographs were taken, the optical laser readings of radiographs were performed by Digora TM system. Five radiographic density readings were performed for each studied material and for each step of the aluminum scale. White ProRoot MTA (155.99±8.04), gray ProRoot MTA (155.96±16.30) and MTA BIO (143.13±16.94) presented higher radiopacity values (pPortland (119.76±22.34), gray Portland (109.71±4.90) and white structural Portland (99.59±12.88) presented lower radiopacity values (pcements were the only materials presenting radiopacity within the ANSI/ADA specifications.

Analyses of heavy metals in mineral trioxide aggregate and Portland cement.

Science.gov (United States)

Schembri, Matthew; Peplow, George; Camilleri, Josette

2010-07-01

Portland cement is used in the construction industry as a binder in concrete. It is manufactured from chalk, limestone, and clay, which are clinkered at very high temperatures and ground with gypsum to form Portland cement. The raw materials and the manufacturing process can result in the inclusion of heavy metals in Portland cement. Portland cement with a four to one addition of bismuth oxide is marketed as mineral trioxide aggregate (MTA), which is used mainly as a dental material. Heavy metal inclusion can be of concern because MTA is in contact with hard and soft tissues. Measurements of arsenic, lead, and chromium in hydrated gray and white Portland cement, ProRoot MTA, and MTA Angelus were conducted with graphite furnace atomic absorption spectrophotometry after acid digestion on the hydrated material. The leaching of the metal ions from the solid material in water and simulated body fluid (SBF) was also determined. All cement types showed high relative values of leached chromium compared with arsenic and lead in both the total metal content and leached species. The gray Portland cement showed the highest total amount of metal. The white Portland and both MTAs had lower values for all the leached metal ions. Both MTAs released more arsenic than the amount specified in ISO 9917-1 (2007). Portland cements and MTAs showed evidence of heavy metals in the acid-soluble form as well as leaching in deionized water and SBF. MTA contained levels of arsenic higher than the safe limit specified by the ISO 9917-1 (2007). Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Quantitative study of Portland cement hydration by X-Ray diffraction/Rietveld analysis and geochemical modeling

Science.gov (United States)

Coutelot, F.; Seaman, J. C.; Simner, S.

2017-12-01

In this study the hydration of Portland cements containing blast-furnace slag and type V fly ash were investigated during cement curing using X-ray diffraction, with geochemical modeling used to calculate the total volume of hydrates. The goal was to evaluate the relationship between the starting component levels and the hydrate assemblages that develop during the curing process. Blast furnace-slag levels of 60, 45 and 30 wt.% were studied in blends containing fly ash and Portland cement. Geochemical modelling described the dissolution of the clinker, and predicted quantitatively the amount of hydrates. In all cases the experiments showed the presence of C-S-H, portlandite and ettringite. The quantities of ettringite, portlandite and the amorphous phases as determined by XRD agreed well with the calculated amounts of these phases after different periods of time. These findings show that changes in the bulk composition of hydrating cements can be described by geochemical models. Such a comparison between experimental and modelled data helps to understand in more detail the active processes occurring during cement hydration.

Effect of blended materials on U(VI) retention characteristics for portland cement solidification product

International Nuclear Information System (INIS)

Tan Hongbin; Ma Xiaoling; Li Yuxiang

2006-01-01

Using the simulated groundwater as leaching liquid, the retention capability of U(VI) in solidification products with Portland cement, the Portland cement containing silica fume, the Portland cement containing metakaolin and the Portland cement containing fly ash was researched by leaching experiments at 25 degree C for 42 d. The results indicate silica fume and metakaolin as blended materials can improve the U(VI) retention capability of Portland cement solidification product, but fly ash can not. (authors)

Re-use of pilot data and interim analysis of pivotal data in MRMC studies: a simulation study

Science.gov (United States)

Chen, Weijie; Samuelson, Frank; Sahiner, Berkman; Petrick, Nicholas

2017-03-01

Novel medical imaging devices are often evaluated with multi-reader multi-case (MRMC) studies in which radiologists read images of patient cases for a specified clinical task (e.g., cancer detection). A pilot study is often used to measure the effect size and variance parameters that are necessary for sizing a pivotal study (including sizing readers, non-diseased and diseased cases). Due to the practical difficulty of collecting patient cases or recruiting clinical readers, some investigators attempt to include the pilot data as part of their pivotal study. In other situations, some investigators attempt to perform an interim analysis of their pivotal study data based upon which the sample sizes may be re-estimated. Re-use of the pilot data or interim analyses of the pivotal data may inflate the type I error of the pivotal study. In this work, we use the Roe and Metz model to simulate MRMC data under the null hypothesis (i.e., two devices have equal diagnostic performance) and investigate the type I error rate for several practical designs involving re-use of pilot data or interim analysis of pivotal data. Our preliminary simulation results indicate that, under the simulation conditions we investigated, the inflation of type I error is none or only marginal for some design strategies (e.g., re-use of patient data without re-using readers, and size re-estimation without using the effect-size estimated in the interim analysis). Upon further verifications, these are potentially useful design methods in that they may help make a study less burdensome and have a better chance to succeed without substantial loss of the statistical rigor.

76 FR 28318 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-05-17

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY... Emission Standards for Hazardous Air Pollutants from the Portland Cement Manufacturing Industry Response to... by the Portland Cement Industry and the New Source Performance Standards for Portland Cement Plants...

76 FR 2832 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-01-18

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY...) from the Portland Cement Manufacturing Industry and Standards of Performance (NSPS) for Portland Cement... Standards for Hazardous Air Pollutant From the Portland Cement Manufacturing Industry Docket, Docket ID No...

Evaluation of the strength and radiopacity of Portland cement with varying additions of bismuth oxide.

Science.gov (United States)

Saliba, E; Abbassi-Ghadi, S; Vowles, R; Camilleri, J; Hooper, S; Camilleri, J

2009-04-01

To study the effect of addition of various proportions of bismuth oxide on compressive strength and radiopacity of Portland cement. The compressive strength of white Portland cement and cement replaced with 10, 15, 20, 25 and 30% bismuth oxide was evaluated by testing cylinders 6 mm in diameter and 12 mm high. Twelve cylinders were tested for each material under study. The radiopacity of the cements tested was evaluated using an aluminium step-wedge and densitometer. The optical density was compared with the relevant thickness of aluminium (Al). Statistical analysis was performed using Analysis of Variance (ANOVA) with P = 0.05 and Tukey test to perform multiple comparison tests. Various additions of bismuth oxide had no significant effect on the strength of the material when compared with the unmodified Portland cement (P > 0.05). The radiopacity of the cements tested ranged from 2.02 mm Al for Portland cement to 9.79 mm Al for the highest bismuth replacement. Addition of bismuth oxide did not affect the compressive strength of Portland cement. All the bismuth oxide cement mixtures had radio-opacities higher than 3 mm thickness of aluminium.

77 FR 46371 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

Science.gov (United States)

2012-08-03

...-AQ93 National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing... Portland Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants,'' which was... Manufacturing Industry and Standards of Performance for Portland Cement Plants'' under Docket ID No. EPA-HQ-OAR...

Utilization of Iron Ore Tailings as Raw Material for Portland Cement Clinker Production

Directory of Open Access Journals (Sweden)

Li Luo

2016-01-01

Full Text Available The cement industry has for some time been seeking alternative raw material for the Portland cement clinker production. The aim of this research was to investigate the possibility of utilizing iron ore tailings (IOT to replace clay as alumina-silicate raw material for the production of Portland cement clinker. For this purpose, two kinds of clinkers were prepared: one was prepared by IOT; the other was prepared by clay as a reference. The reactivity and burnability of raw meal, mineralogical composition and physical properties of clinker, and hydration characteristic of cement were studied by burnability analysis, differential thermal analysis, X-ray diffraction, and hydration analysis. The results showed that the raw meal containing IOT had higher reactivity and burnability than the raw meal containing clay, and the use of IOT did not affect the formation of characteristic mineralogical phases of Portland cement clinker. Furthermore, the physical and mechanical performance of two cement clinkers were similar. In addition, the use of IOT was found to improve the grindability of clinker and lower the hydration heat of Portland cement. These findings suggest that IOT can replace the clay as alumina-silicate raw material for the preparation of Portland cement clinker.

Alkali binding in hydrated Portland cement paste

NARCIS (Netherlands)

Chen, Wei; Brouwers, Jos

2010-01-01

The alkali-binding capacity of C–S–H in hydrated Portland cement pastes is addressed in this study. The amount of bound alkalis in C–S–H is computed based on the alkali partition theories firstly proposed by Taylor (1987) and later further developed by Brouwers and Van Eijk (2003). Experimental data

Hydration study of ordinary portland cement in the presence of zinc ions

Directory of Open Access Journals (Sweden)

Monica Adriana Trezza

2007-12-01

Full Text Available Hydration products of Portland cement pastes, hydrated in water and in the presence of zinc ions were studied comparatively at different ages. Hydration products were studied by X ray diffractions (XRD and infrared spectroscopy (IR. Although IR is not frequently used in cement chemistry, it evidenced a new phase Ca(Zn(OH32. 2H2O formed during cement hydration in the presence of zinc. The significant retardation of early cement hydration in the presence of zinc is assessed in detail by differential calorimetry as a complement to the study carried out by IR and XRD, providing evidence that permits to evaluate the kinetic of the early hydration.

Physical and Thermodynamical Properties of Water Phases in Hardening Portland Cement Systems

DEFF Research Database (Denmark)

Hansen, T. Bæk

The present study is devoted to the description of water phases in hardening portland cement paste systems containing a significant amount of micro-filler and having a low to moderate water/powder ratio. Emphasis has been placed on the early stages of the hardening process.......The present study is devoted to the description of water phases in hardening portland cement paste systems containing a significant amount of micro-filler and having a low to moderate water/powder ratio. Emphasis has been placed on the early stages of the hardening process....

Analysis of heavy metal contents in gray and white MTA and 2 kinds of Portland cement: a preliminary study.

Science.gov (United States)

Chang, Seok Woo; Shon, Won Jun; Lee, WooCheol; Kum, Kee Yeon; Baek, Seung Ho; Bae, Kwang Shik

2010-04-01

The levels of 10 heavy metals (arsenic, bismuth, cadmium, chromium, copper, iron, lead, manganese, nickel, and zinc) in gray Portland cement (GPC), white Portland cement (WPC), gray MTA (GMTA), and white MTA (WMTA) were analyzed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). One gram of each material was digested with 80 degrees C "aqua-regia" (7 mL of 60% HNO3 and 21 mL of 35% HCl), filtered, and analyzed by ICP-AES. The analysis was performed 6 times and the data were analyzed statistically. Arsenic and lead concentrations were the highest in GPC (P cements (P Portland cement versus MTA, the differences in purity may be considered. Copyright 2010 Mosby, Inc. All rights reserved.

Electrically conductive Portland cement concrete.

Science.gov (United States)

1986-01-01

There is a need for an effective, simple-to-install secondary anode system for use in the cathodic protection of reinforced concrete bridge decks. In pursuit of such a system, carbon fibers and carbon black were incorporated in portland cement concre...

Mineral trioxide aggregate and Portland cement promote biomineralization in vivo.

Science.gov (United States)

Dreger, Luonothar Antunes Schmitt; Felippe, Wilson Tadeu; Reyes-Carmona, Jessie Fabiola; Felippe, Gabriela Santos; Bortoluzzi, Eduardo Antunes; Felippe, Mara Cristina Santos

2012-03-01

Mineral trioxide aggregate (MTA) and Portland cement have been shown to be bioactive because of their ability to produce biologically compatible carbonated apatite. This study analyzed the interaction of MTA and white Portland cement with dentin in vivo. Seventy-two human dentin tubes were filled with MTA Branco, MTA BIO, and white Portland cement + 20% bismuth oxide (PC1) or PC1 + 10% of calcium chloride (PC2) and implanted subcutaneously in 18 rats at 4 sites from the dorsal area. Empty dentin tubes, implanted in rats of a pilot study, were used as control. After 30, 60, and 90 days, the animals were killed, and the dentin tubes were retrieved for scanning electron microscope analysis. In the periods of 30 and 60 days, the mineral deposition in the material-dentin interface (interfacial layer) and in the interior of dentinal tubules was detected in more tubes filled with MTA Branco and MTA BIO than in tubes filled with PC1 and PC2. After 90 days, the interfacial layer and intratubular mineralization were detected in all tubes except for 3 and 1 of the tubes filled with PC2, respectively. It was concluded that all the cements tested were bioactive. The cements released some of their components in the tissue capable of stimulating mineral deposition in the cement-dentin interface and in the interior of the dentinal tubules. MTA BIO and MTA Branco were more effective in promoting the biomineralization process than Portland cements, mainly after 30 and 60 days. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

An interim report on the State of Nevada socioeconomic studies

International Nuclear Information System (INIS)

1989-06-01

This Interim Report is a report on work in progress and presents findings from the research to date on the potential consequences of a repository for the citizens of Nevada. The research and findings in the Report have been subjected to rigorous peer review as part of the state's effort to insure independent, objective analysis that meets the highest professional standards. The basic research effort will continue through June 1990 and will enable the state to refine and clarify the findings presented in this Interim Report

400-MWe Consolidated Nuclear Steam System (CNSS). 1200-MWt Phase 2A interim studies

International Nuclear Information System (INIS)

1978-09-01

The Phase 2A interim studies of the Consolidated Nuclear Steam System (CNSS) consisted of a number of separate task studies addressing the design concepts developed during the Phase 1 study reported in BAW--1445. The purpose of the interim studies was to better establish overall concept feasibility from both a hardware and economic standpoint, to make modification and additions to the design where appropriate, and to understand and reduce the technical risks in critical areas of the design. The work on these task studies included input from Barberton, Mt. Vernon, and the Alliance Research Center as well as United Engineers and Constructors (UE and C). The UE and C work was carried out under a separate DOE contract

Chemical composition, radiopacity, and biocompatibility of Portland cement with bismuth oxide.

Science.gov (United States)

Hwang, Yun-Chan; Lee, Song-Hee; Hwang, In-Nam; Kang, In-Chol; Kim, Min-Seok; Kim, Sun-Hun; Son, Ho-Hyun; Oh, Won-Mann

2009-03-01

This study compared the chemical constitution, radiopacity, and biocompatibility of Portland cement containing bismuth oxide (experimental cement) with those of Portland cement and mineral trioxide aggregate (MTA). The chemical constitution of materials was determined by scanning electron microscopy and energy-dispersive X-ray analysis. The radiopacity of the materials was determined using the ISO/6876 method. The biocompatibility of the materials was tested by MTT assay and tissue reaction. The constitution of all materials was similar. However, the Portland cement and experimental cement were more irregular and had a larger particle size than MTA. The radiopacity of the experimental cement was similar to MTA. The MTT assay revealed MTA to have slightly higher cell viability than the other materials. However, there were no statistically significant differences between the materials, with the exception of MTA at 24 h. There was no significant difference in the tissue reaction between the experimental groups. These results suggest that the experimental cement may be used as a substitute for MTA.

Interim overdentures.

Science.gov (United States)

Fenton, A H

1976-07-01

The construction of an interim overdenture using existing removable partial dentures with natural tooth crowns and artificial teeth can be a simple and economical method of providing patients with dentures while tissues heal and teeth are prepared and restored. A more definite prognosis for both the patient and his remaining dentition can be established before the final overdenture is completed. The procedures necessary to provide three types of interim overdentures have been outlined. Patients tolerate this method of changing their dentitions extremely well.

Retention of long-term interim restorations with sodium fluoride enriched interim cement

Science.gov (United States)

Strash, Carolyn

Purpose: Interim fixed dental prostheses, or "provisional restorations", are fabricated to restore teeth when definitive prostheses are made indirectly. Patients undergoing extensive prosthodontic treatment frequently require provisionalization for several months or years. The ideal interim cement would retain the restoration for as long as needed and still allow for ease of removal. It would also avoid recurrent caries by preventing demineralization of tooth structure. This study aims to determine if adding sodium fluoride varnish to interim cement may assist in the retention of interim restorations. Materials and methods: stainless steel dies representing a crown preparation were fabricated. Provisional crowns were milled for the dies using CAD/CAM technology. Crowns were provisionally cemented onto the dies using TempBond NE and NexTemp provisional cements as well as a mixture of TempBond NE and Duraphat fluoride varnish. Samples were stored for 24h then tested or thermocycled for 2500 or 5000 cycles before being tested. Retentive strength of each cement was recorded using a universal testing machine. Results: TempBond NE and NexTemp cements performed similarly when tested after 24h. The addition of Duraphat significantly decreased the retention when added to TempBond NE. NexTemp cement had high variability in retention over all tested time periods. Thermocycling for 2500 and 5000 cycles significantly decreased the retention of all cements. Conclusions: The addition of Duraphat fluoride varnish significantly decreased the retention of TempBond NE and is therefore not recommended for clinical use. Thermocycling significantly reduced the retention of TempBond NE and NexTemp. This may suggest that use of these cements for three months, as simulated in this study, is not recommended.

Radioactive waste interim storage in Germany

International Nuclear Information System (INIS)

2015-12-01

The short summary on the radioactive waste interim storage in Germany covers the following issues: importance of interim storage in the frame of radioactive waste management, responsibilities and regulations, waste forms, storage containers, transport of vitrified high-level radioactive wastes from the reprocessing plants, central interim storage facilities (Gorleben, Ahaus, Nord/Lubmin), local interim storage facilities at nuclear power plant sites, federal state collecting facilities, safety, radiation exposure in Germany.

Sulfatos en el cemento portland y su incidencia sobre el falso fraguado: Estado actual del conocimiento

Directory of Open Access Journals (Sweden)

de la Cruz, Ignacio

1983-12-01

Full Text Available A bibliographical study is carried out of the sulphates which may be present in the clinker and Portland cement, as likewise the effects of the aeration and temperature on the setting. This work is a prior phase of a wide experimental investigation carried out in the IETCC, on anomalies or setting and phenomena of "lumping" in Portland cement.

Se realiza un estudio bibliográfico de los sulfatos que pueden estar presentes en el clínker y cemento portland, así como de los efectos de la aireación y temperatura sobre el fraguado. Este trabajo es la fase previa de una amplia investigación experimental realizada en el IETCC, sobre anomalías de fraguado y fenómenos de "aterronamiento" en el cemento portland.

Pulp tissue response to Portland cement associated with different radio pacifying agents on pulpotomy of human primary molars.

Science.gov (United States)

Marques, N; Lourenço Neto, N; Fernandes, A P; Rodini, C; Hungaro Duarte, M; Rios, D; Machado, M A; Oliveira, T

2015-12-01

The objective of this research was to evaluate the response of Portland cement associated with different radio pacifying agents on pulp treatment of human primary teeth by clinical and radiographic exams and microscopic analysis. Thirty mandibular primary molars were randomly divided into the following groups: Group I - Portland cement; Group II - Portland cement with iodoform (Portland cement + CHI3 ); Group III - Portland cement with zirconium oxide (Portland cement + ZrO2 ); and treated by pulpotomy technique (removal of a portion of the pulp aiming to maintain the vitally of the remaining radicular pulp tissue using a therapeutic dressing). Clinical and radiographic evaluations were recorded at 6, 12 and 24 months follow-up. The teeth at the regular exfoliation period were extracted and processed for histological analysis. Data were tested using statistical analysis with a significance level of 5%. The microscopic findings were descriptively analysed. All treated teeth were clinically and radiographically successful at follow-up appointments. The microscopic analysis revealed positive response to pulp repair with hard tissue barrier formation and pulp calcification in the remaining roots of all available teeth. The findings of this study suggest that primary teeth pulp tissue exhibited satisfactory biological response to Portland cement associated with radio pacifying agents. However, further studies with long-term follow-up are needed to determine the safe clinical indication of this alternative material for pulp therapy of primary teeth. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

40 CFR 81.78 - Metropolitan Portland Intrastate Air Quality Control Region.

Science.gov (United States)

2010-07-01

... Quality Control Region. 81.78 Section 81.78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... Air Quality Control Regions § 81.78 Metropolitan Portland Intrastate Air Quality Control Region. The Metropolitan Portland Intrastate Air Quality Control Region (Maine) consists of the territorial area...

Study irradiation damage by fast neutrons in Portland cement by means of ultra-sound

International Nuclear Information System (INIS)

Rosa Junior, A.A.

1988-01-01

The effect of neutron irradiation in samples of Portland cement paste was evaluated, using the resonance frequency method and pulse velocity of ultra-sound technique. The samples were divide in three groups: 1) Monitoring samples; 2) Samples to gamma heating simulation; 3) Fast neutron irradiated samples in reactor core. Santa Rita Portland cement was utilized for samples preparation with water-cement rate of 0,40 l/kg. The irradiation was performed in the research reactor IEA-R1, at IPEN-CNEN/SP, with an integrated flux of 7,2 X 10 sup(18) n/cm sup(2) (E approx. 1 Mev). The samples of group 2 were submitted to special micro-waves heat treatment-with the same number of cycles of the reactor-which allowed the detection of fast neutron radiation effects within the predominant thermal effects. (author)

EnviroAtlas - Portland, OR - Meter-Scale Urban Land Cover (MULC) Data (2012)

Data.gov (United States)

U.S. Environmental Protection Agency — The EnviroAtlas Portland, OR Meter-Scale Urban Land Cover (MULC) dataset includes data for the Portland metropolitan area plus the city of Vancouver, Washington and...

Influence of ultrasonic radiation on the amorphous zeolite - Portland cement system

NARCIS (Netherlands)

Jakevicius, L.; Vaiciukyniene, D.; Demcenko, A.

2012-01-01

This paper considers the investigation of influence of an amorphous synthetic zeolite with inserted $Ca^{2+}$ ions additive (ASZ) on the hydration temperature of Portland cement paste. In this investigation the sonicated Portland cement paste is compared to the non-sonicated paste; and then the

Portland-pfa cement: a comparison between intergrinding and blending

Energy Technology Data Exchange (ETDEWEB)

Monk, M

1983-09-01

Portland-pfa cements containing 20-40% (by weight) pfa have been prepared in the laboratory both by intergrinding the ashes with clinker and by blending with cement. Cement properties have been assessed according to BS 4550 and scanning electron microscopy was used to examine the effects of grinding upon the pfa particles. The work has shown that intergrinding leads to an improvement in the water-reducing properties of coarse pfas and also in their pozzolanic activity as indicated by compressive strength development at later ages. Setting times have been found to be essentially the same for blended and interground cements, both being considerably longer than for typical ordinary Portland cements. Thus the results of this investigation indicate that, provided pfa's are chemically acceptable, they can be used for Portland-pfa cement manufacture by intergrinding irrespective of their coarseness.

A comparative evaluation of compressive strength of Portland cement with zinc oxide eugenol and Polymer-reinforced cement: an in vitro analysis.

Science.gov (United States)

Prakasam, S; Bharadwaj, Prakasam; Loganathan, S C; Prasanth, B Krishna

2014-01-01

The purpose of this study is to evaluate the ultimate compressive strength of 50% and 25% Portland cement mixed with Polymer-reinforced zinc oxide eugenol and zinc oxide eugenol cement after 1 hour, 24 hours, and 7 days. One hundred and eighty samples were selected. The samples were made cylindrical of size 6 × 8 mm and were divided into six groups as follows with each group consisting of 10 samples. Group 1: Polymer-reinforced zinc oxide eugenol with 50% Portland cement (PMZNPC 50%) Group 2: Polymer-reinforced zinc oxide eugenol with 25% Portland cement (PMZNPC 25%) Group 3: Polymer-reinforced zinc oxide eugenol with 0% Portland cement (PMZNPC 0%) Group 4: Zinc oxide eugenol with 50% Portland cement (ZNPC 50%) Group 5: Zinc oxide eugenol with 25% Portland cement (ZNPC 25%) Group 6: Zinc oxide eugenol with 0% Portland cement (ZNPC 0%) These samples were further subdivided based on time interval and were tested at 1 hour, 24 hours and at 7 th day. After each period of time all the specimens were tested by vertical CVR loaded frame with capacity of 5 tones/0473-10kan National Physical laboratory, New Delhi and the results were statistically analyzed using ANOVA and Scheffe test. Polymer-reinforced cement with 50% Portland cement, Zinc oxide with 50% Portland cement, Polymer-reinforced cement with 25% Portland cement and Zinc oxide with 25% Portland cement exhibited higher compressive strength when compared to Zinc oxide with 0% Portland cement and Polymer-reinforced cement with 0% Portland cement, at different periods of time. The difference between these two groups were statistically significant (P Portland cement in Zinc oxide eugenol and Polymer-modified zinc oxide cement can be used as core build up material and permanent filling material. It is concluded that 50% and 25% Portland cement in zinc oxide eugenol and polymer-modified zinc oxide eugenol results in higher compressive strength and hence can be used as permanent filling material and core built

Assessment of Pollution Potentialities of some Portland Cement ...

African Journals Online (AJOL)

Chemical analysis of some Portland cement commonly used in Nigeria was carried out. All the cement studies were found to be good for concrete work especially where no special property is required. The concentration levels of heavy metals in all the cement samples were above the tolerance limit and therefore need to ...

77 FR 42367 - National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing...

Science.gov (United States)

2012-07-18

... and 63 National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing... Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry and Standards of... manufacturing plants. Federal government Not affected. State/local/tribal government.... Portland cement...

7 CFR 1738.21 - Interim financing.

Science.gov (United States)

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Interim financing. 1738.21 Section 1738.21... Interim financing. (a) Upon notification by RUS that an applicant's application is considered complete, the applicant may enter into an interim financing agreement with a lender other than RUS or use its...

2015 City of Portland, Maine, Lidar

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 2015 City of Portland Maine Lidar Data Acquisition and Processing Woolpert Order No. 75564 Contractor: Woolpert, Inc. This task is for a high resolution data set of...

Analysis of Chemical Composition of Portland Cement in Ghana: A Key to Understand the Behavior of Cement

OpenAIRE

Bediako, Mark; Amankwah, Eric Opoku

2015-01-01

The performance of Portland cement in concrete or mortar formation is very well influenced by chemical compositions among other factors. Many engineers usually have little information on the chemical compositions of cement in making decisions for the choice of commercially available Portland cement in Ghana. This work analyzed five different brands of Portland cement in Ghana, namely, Ghacem ordinary Portland cement (OPC) and Portland limestone cement (PLC), CSIR-BRRI Pozzomix, Dangote OPC, a...

75 FR 54969 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2010-09-09

... Hazardous Air Pollutants From the Portland Cement Manufacturing Industry and Standards of Performance for... Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing Industry and Standards of... (NESHAP) from the Portland Cement Manufacturing Industry and to the New Source Performance Standards (NSPS...

76 FR 2860 - National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing...

Science.gov (United States)

2011-01-18

... Cement Manufacturing Industry and Standards of Performance for Portland Cement Plants AGENCY... Portland Cement Manufacturing Industry Docket, Docket ID No. EPA-HQ-OAR-2002-0051, 1200 Pennsylvania Ave... Portland Cement Manufacturing Industry Docket, EPA West, Room 3334, 1301 Constitution Ave., NW., Washington...

400-MWe Consolidated Nuclear Steam System (CNSS). 1200-MWt Phase 2A interim studies. [PWR

Energy Technology Data Exchange (ETDEWEB)

1978-09-01

The Phase 2A interim studies of the Consolidated Nuclear Steam System (CNSS) consisted of a number of separate task studies addressing the design concepts developed during the Phase 1 study reported in BAW--1445. The purpose of the interim studies was to better establish overall concept feasibility from both a hardware and economic standpoint, to make modification and additions to the design where appropriate, and to understand and reduce the technical risks in critical areas of the design. The work on these task studies included input from Barberton, Mt. Vernon, and the Alliance Research Center as well as United Engineers and Constructors (UE and C). The UE and C work was carried out under a separate DOE contract.

Stabilization of marly soils with portland cement

Science.gov (United States)

Piskunov, Maksim; Karzin, Evgeny; Lukina, Valentina; Lukinov, Vitaly; Kholkin, Anatolii

2017-10-01

Stabilization of marlous soils with Portland cement will increase the service life of motor roads in areas where marl is used as a local road construction material. The result of the conducted research is the conclusion about the principal possibility of stabilization of marlous soils with Portland cement, and about the optimal percentage of the mineral part and the binding agent. When planning the experiment, a simplex-lattice plan was implemented, which makes it possible to obtain a mathematical model for changing the properties of a material in the form of polynomials of incomplete third order. Brands were determined for compressive strength according to GOST 23558-94 and variants of stabilized soils were proposed for road construction.

7 CFR 1735.75 - Interim financing.

Science.gov (United States)

2010-01-01

... 7 Agriculture 11 2010-01-01 2010-01-01 false Interim financing. 1735.75 Section 1735.75... Involving Loan Funds § 1735.75 Interim financing. (a) A borrower may submit a written request for RUS approval of interim financing if it is necessary to close an acquisition before the loan to finance the...

Portland cement hydration in the presence of admixtures: black gram pulse and superplasticizer

Directory of Open Access Journals (Sweden)

Viveka Nand Dwivedi

2008-12-01

Full Text Available Effect of admixtures such as black gram pulse (BGP and sulfonated naphthalene based superplasticizer (SP on the hydration of Portland cement has been studied. The hydration characteristics of OPC in the presence of BGP and SP were studied with the help of non evaporable water content determinations, calorimetric method, Mössbauer spectroscopic and atomic force microscopic techniques. Results have shown that both BGP and SP get adsorbed at the surface of cement and its hydration products. The hydration of Portland cement is retarded in the presence of both the admixtures and nanosize hydration products are formed.

76 FR 78240 - Gray Portland Cement and Clinker From Japan: Continuation of Antidumping Duty Order

Science.gov (United States)

2011-12-16

... DEPARTMENT OF COMMERCE International Trade Administration [A-588-815] Gray Portland Cement and... Department) initiated the third sunset review of the antidumping duty order on gray portland cement and... of the antidumping duty order on gray portland cement and clinker from Japan would likely lead to...

Radiopacity and histological assessment of Portland cement plus bismuth oxide.

Science.gov (United States)

Coutinho-Filho, Tauby; De-Deus, Gustavo; Klein, Leila; Manera, Gisele; Peixoto, Carla; Gurgel-Filho, Eduardo Diogo

2008-12-01

The present study evaluated the subcutaneous connective tissue reactions and the radiopacity of MTA, Portland cement (PC), and Portland cement plus bismuth oxide (BO). Forty rats were divided into 5 groups (n = 8 per group): A1: Control (empty capsule); A2: Pro-Root MTA; A3: PC; A4: PC + BO 1:1; and A5: PC + BO 2:1. Polyethylene tubes were filled with the test materials and standardized radiographic images were taken. Histological evaluation was done after 7 and 60 days. Student t test and Fisher's test were used in the statistical analysis (P A4 > A5 > A3. No differences were found for the tissue response in the 2 experimental periods. A positive correlation between BO concentration and radiopacity of PC was determined. The histological evaluation suggests that all studied materials were biocompatible at 7 and 60 days.

Physicochemical Properties of MTA and Portland Cement after Addition of Aloe Vera.

Science.gov (United States)

Henrique Borges, Alvaro; Aguirre Guedes, Orlando; Evaristo Ricci Volpato, Luiz; Siebert Filho, Gilberto; Meireles Borba, Alexandre; Zina, Omar; Piva, Evandro; Estrela, Carlos

2017-01-01

The aim of this in vitro study was to determine the liquid-powder ratio, setting time, solubility, dimensional change, pH, and radiopacity of white structural and non-structural Portland cement, ProRoot MTA and MTA Bio, associated with a 2% glycolic solution containing Aloe Vera, as vehicle. Five samples of each material were used for each test, according to the American National Standards Institute/American Dental Association (ANSI/ADA) specification No. 57. Statistical analyses were performed using ANOVA and Tukey's test at 5% significance. When sample distribution was not normal, non-parametric analysis of variance and the Kruskal-Wallis test were used ( α =0.05). No statistical differences were found in liquid-powder ratios among the tested materials. ProRoot MTA showed the longest setting time. Dimensional change values were acceptable in all groups. Also, no significant differences were found in pH values and pH was alkaline in all samples throughout the experiment. Mean radiopacity results obtained for white Portland cements did not meet ANSI/ADA requirements, and were significantly lower than those obtained for MTA-based cements. Finally, Portland cements showed significantly higher mean solubility values compared to the other samples. The physicochemical properties of the tested materials in association with Aloe Vera were compatible with ANSI/ADA requirements, except for the white Portland cements, which failed to meet the radiopacity specification.

Root perforations treatment using mineral trioxide aggregate and Portland cements.

Science.gov (United States)

Silva Neto, José Dias da; Brito, Rafael Horácio de; Schnaider, Taylor Brandão; Gragnani, Alfredo; Engelman, Mírian; Ferreira, Lydia Masako

2010-12-01

Clinical, radiological and histological evaluation of root perforations treated with mineral trioxide aggregate (MTA) or Portland cements, and calcium sulfate barrier. One molar and 11 premolar teeth of a male mongrel dog received endodontic treatment and furcations were perforated with a high-speed round bur and treated with a calcium sulfate barrier. MTA, Portland cement type II (PCII) and type V (PCV), and white Portland cement (WPC) were used as obturation materials. The teeth were restored with composite resin and periapical radiographs were taken. The animal was euthanized 120 days post-surgery for treatment evaluation. Right lower first premolar (MTA), right lower third premolar (PCV), left lower second premolar (MTA), and right lower second premolar (WPC): clinically normal, slightly radio-transparent area on the furcation, little inflammatory infiltrate, and new-bone formation. Left lower third premolar (PCII), right upper first premolar (WPC), right upper third premolar (PCII), and left upper first molar (PCV): clinically normal, radiopaque area on the furcation, and new-bone formation. Right upper second premolar (MTA), left upper second premolar (WPC), left upper third premolar (PCII): presence of furcation lesion, large radiolucent area, and intense inflammatory infiltrate. All obturation materials used in this study induced new-bone formation.

13 CFR 120.890 - Source of interim financing.

Science.gov (United States)

2010-01-01

... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Source of interim financing. 120... Development Company Loan Program (504) Interim Financing § 120.890 Source of interim financing. A Project may use interim financing for all Project costs except the Borrower's contribution. Any source (including...

Comparative study of physico-chemical properties of MTA-based and Portland cements.

Science.gov (United States)

Borges, Alvaro H; Pedro, Fábio L M; Miranda, Carlos E S; Semenoff-Segundo, Alex; Pécora, Jesus D; Filho, Antônio M Cruz

2010-01-01

The purpose of this investigation was to evaluate the physicochemical properties of gray and white structural and nonstructural Portland cement, gray and white ProRoot MTA and MTA BIO. The water/powder ratio, setting time, solubility and pH (hydrogen-ion potential) changes of the materials were evaluated. Tests followed specification #57 from the American National Standard Institute/American Dental Association (2000) for endodontic sealing materials and pH was determined by a digital pH meter. The test results were statistically analyzed by variance analyses for global comparison and by the complementary Tukey's test for pairwise comparisons (5%). Considering the water/powder ratio, no significant difference (p > 0.05) was observed among the cements. MTA BIO (33.10 +/- 2.30) had the lowest setting time (p Portland cement (2.55 +/- 0.08) had the highest solubility (p 0.05) was observed among materials when considering pH evaluation. The pH levels were highly alkaline immediately after immersion in solution, remaining stable throughout the test period. The authors conclude that the cements had similar water/powder proportions. MTA BIO had the shortest setting time and gray ProRoot MTA had the lowest solubility. All cements had similar behavior in the pH analysis.

A comparison of the value relevance of interim and annual financial statements

Directory of Open Access Journals (Sweden)

Mbalenhle Zulu

2017-03-01

Aim: It explores whether the value relevance of interim financial statements is higher than the value relevance of annual financial statements. Finally, it investigates whether accounting information published in interim and annual financial statements has incremental value relevance. Setting: Data for the period from 1999 to 2012 were collected from a sample of non-financial companies listed on the Johannesburg Stock Exchange. Method: The Ohlson model to investigate the value relevance of accounting information was used for the study. Results: The results show that interim book value of equity is value relevant while interim earnings are not. Interim financial statements appear to have higher value relevance than annual financial statements. The value relevance of interim and annual accounting information has remained fairly constant over the sample period. Incremental comparisons provide evidence that additional book value of equity and earnings that accrue to a company between interim and annual reporting dates are value relevant. Conclusion: The study was conducted over a long sample period (1999–2012, in an era when a technology-driven economy and more timely reporting media could have had an effect on the value relevance of published accounting information. To the best of our knowledge, this is the first study to evaluate and compare the value relevance of published interim and annual financial statements.

Synthesis of Portland cement and calcium sulfoaluminate-belite cement for sustainable development and performance

Science.gov (United States)

Chen, Irvin Allen

Portland cement concrete, the most widely used manufactured material in the world, is made primarily from water, mineral aggregates, and portland cement. The production of portland cement is energy intensive, accounting for 2% of primary energy consumption and 5% of industrial energy consumption globally. Moreover, portland cement manufacturing contributes significantly to greenhouse gases and accounts for 5% of the global CO2 emissions resulting from human activity. The primary objective of this research was to explore methods of reducing the environmental impact of cement production while maintaining or improving current performance standards. Two approaches were taken, (1) incorporation of waste materials in portland cement synthesis, and (2) optimization of an alternative environmental friendly binder, calcium sulfoaluminate-belite cement. These approaches can lead to less energy consumption, less emission of CO2, and more reuse of industrial waste materials for cement manufacturing. In the portland cement part of the research, portland cement clinkers conforming to the compositional specifications in ASTM C 150 for Type I cement were successfully synthesized from reagent-grade chemicals with 0% to 40% fly ash and 0% to 60% slag incorporation (with 10% intervals), 72.5% limestone with 27.5% fly ash, and 65% limestone with 35% slag. The synthesized portland cements had similar early-age hydration behavior to commercial portland cement. However, waste materials significantly affected cement phase formation. The C3S--C2S ratio decreased with increasing amounts of waste materials incorporated. These differences could have implications on proportioning of raw materials for cement production when using waste materials. In the calcium sulfoaluminate-belite cement part of the research, three calcium sulfoaluminate-belite cement clinkers with a range of phase compositions were successfully synthesized from reagent-grade chemicals. The synthesized calcium sulfoaluminate

33 CFR 165.1312 - Security Zone; Portland Rose Festival on Willamette River.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; Portland Rose Festival on Willamette River. 165.1312 Section 165.1312 Navigation and Navigable Waters COAST GUARD... § 165.1312 Security Zone; Portland Rose Festival on Willamette River. (a) Location. The following area...

78 FR 4331 - Safety Zone; Sellwood Bridge Move; Willamette River, Portland, OR

Science.gov (United States)

2013-01-22

... Sellwood Bridge as it is being moved. This safety zone will also allow full maneuverability for... 1625-AA00 Safety Zone; Sellwood Bridge Move; Willamette River, Portland, OR AGENCY: Coast Guard, DHS... the Sellwood Bridge, located on the Willamette River in Portland, Oregon, while it is being relocated...

Engineering study: disposition of terminal liquors for interim storage

International Nuclear Information System (INIS)

Metz, W.P.; Ogren, W.E.

1975-02-01

Eight alternative processes were chosen as being technologically feasible within the time frame dictated by budgeting procedures and terminal liquor availability. Solidified waste products acceptable for single-shell tank storage were assumed to be placed in available single-shell tanks. Double-shell tanks were used only for the more mobile terminal liquors or semi-solid mush products. The mush, chemical neutralization, and clay in-tank processes offer potential savings of tens of millions of dollars over double-shell tank storage of terminal liquors. In order to achieve this cost savings, the process development and demonstration must be completed prior to the beginning of double-shell tank construction (Dec. 1976) expected to be funded from a fiscal year 1977 line item. Budgeting for these additional double-shell tanks must proceed since the processing options discussed here are not yet available and may not prove to be available at the required time. This study indicates the following topics for additional study: Process technology development to achieve interim storage of terminal liquor products receives the greatest emphasis as a means of reducing capital expenditures. Interim storage product criteria, waste inventory, and conversion to final form require definition to allow comparison of the alternatives for disposition of terminal liquors. The pseudotechnical nature of product acceptability criteria is important to the evaluation of the partial neutralization and aluminum removal alternatives. More accurate estimates of terminal liquor quantity and composition are required to give a sound technical basis for choosing the appropriate processing alternative. Retrieval and reprocessing operations may affect the comparisons presented by this study

Evaluation of ERA-Interim precipitation data in complex terrain

Science.gov (United States)

Gao, Lu; Bernhardt, Matthias; Schulz, Karsten

2013-04-01

Precipitation controls a large variety of environmental processes, which is an essential input parameter for land surface models e.g. in hydrology, ecology and climatology. However, rain gauge networks provides the necessary information, are commonly sparse in complex terrains, especially in high mountainous regions. Reanalysis products (e.g. ERA-40 and NCEP-NCAR) as surrogate data are increasing applied in the past years. Although they are improving forward, previous studies showed that these products should be objectively evaluated due to their various uncertainties. In this study, we evaluated the precipitation data from ERA-Interim, which is a latest reanalysis product developed by ECMWF. ERA-Interim daily total precipitation are compared with high resolution gridded observation dataset (E-OBS) at 0.25°×0.25° grids for the period 1979-2010 over central Alps (45.5-48°N, 6.25-11.5°E). Wet or dry day is defined using different threshold values (0.5mm, 1mm, 5mm, 10mm and 20mm). The correspondence ratio (CR) is applied for frequency comparison, which is the ratio of days when precipitation occurs in both ERA-Interim and E-OBS dataset. The result shows that ERA-Interim captures precipitation occurrence very well with a range of CR from 0.80 to 0.97 for 0.5mm to 20mm thresholds. However, the bias of intensity increases with rising thresholds. Mean absolute error (MAE) varies between 4.5 mm day-1 and 9.5 mm day-1 in wet days for whole area. In term of mean annual cycle, ERA-Interim almost has the same standard deviation of the interannual variability of daily precipitation with E-OBS, 1.0 mm day-1. Significant wet biases happened in ERA-Interim throughout warm season (May to August) and dry biases in cold season (November to February). The spatial distribution of mean annual daily precipitation shows that ERA-Interim significant underestimates precipitation intensity in high mountains and northern flank of Alpine chain from November to March while pronounced

Disposal facility data for the interim performance

International Nuclear Information System (INIS)

Eiholzer, C.R.

1995-01-01

The purpose of this report is to identify and provide information on the waste package and disposal facility concepts to be used for the low-level waste tank interim performance assessment. Current concepts for the low-level waste form, canister, and the disposal facility will be used for the interim performance assessment. The concept for the waste form consists of vitrified glass cullet in a sulfur polymer cement matrix material. The waste form will be contained in a 2 x 2 x 8 meter carbon steel container. Two disposal facility concepts will be used for the interim performance assessment. These facility concepts are based on a preliminary disposal facility concept developed for estimating costs for a disposal options configuration study. These disposal concepts are based on vault type structures. None of the concepts given in this report have been approved by a Tank Waste Remediation Systems (TWRS) decision board. These concepts will only be used in th interim performance assessment. Future performance assessments will be based on approved designs

Gravity Data for the Greater Portland Area

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The gravity station data (1,522 records) were compiled by the Portland State University. This data base was received in August 1990. Principal gravity parameters...

Strategic Planning to Advance Equity on Campus: A Case Study at Portland State University

Science.gov (United States)

Zapata, Marisa; Percy, Stephen; Andrews, Sona

2018-01-01

Propelled by many factors, including a newly appointed Board of Trustees responsible for governance of our university, resource shortages, and enrollment swings, Portland State University embarked on a strategic planning effort in 2014 with the intent of reunifying a divided campus and creating a bold vision for moving forward in the next five…

Hydration characteristics of zirconium oxide replaced Portland cement for use as a root-end filling material.

Science.gov (United States)

Camilleri, J; Cutajar, A; Mallia, B

2011-08-01

Zirconium oxide can be added to dental materials rendering them sufficiently radiopaque. It can thus be used to replace the bismuth oxide in mineral trioxide aggregate (MTA). Replacement of Portland cement with 30% zirconium oxide mixed at a water/cement ratio of 0.3 resulted in a material with adequate physical properties. This study aimed at investigating the microstructure, pH and leaching in physiological solution of Portland cement replaced zirconium oxide at either water-powder or water-cement ratios of 0.3 for use as a root-end filling material. The hydration characteristics of the materials which exhibited optimal behavior were evaluated. Portland cement replaced by zirconium oxide in varying amounts ranging from 0 to 50% in increments of 10 was prepared and divided into two sets. One set was prepared at a constant water/cement ratio while the other set at a constant water/powder ratio of 0.3. Portland cement and MTA were used as controls. The materials were analyzed under the scanning electron microscope (SEM) and the hydration products were determined. X-ray energy dispersive analysis (EDX) was used to analyze the elemental composition of the hydration products. The pH and the amount of leachate in Hank's balanced salt solution (HBSS) were evaluated. A material that had optimal properties that satisfied set criteria and could replace MTA was selected. The microstructure of the prototype material and Portland cement used as a control was assessed after 30 days using SEM and atomic ratio diagrams of Al/Ca versus Si/Ca and S/Ca versus Al/Ca were plotted. The hydration products of Portland cement replaced with 30% zirconium oxide mixed at water/cement ratio of 0.3 were calcium silicate hydrate, calcium hydroxide and minimal amounts of ettringite and monosulphate. The calcium hydroxide leached in HBSS solution resulted in an increase in the pH value. The zirconium oxide acted as inert filler and exhibited no reaction with the hydration by-products of Portland

Burn site groundwater interim measures work plan.

Energy Technology Data Exchange (ETDEWEB)

Witt, Jonathan L. (North Wind, Inc., Idaho Falls, ID); Hall, Kevin A. (North Wind, Inc., Idaho Falls, ID)

2005-05-01

This Work Plan identifies and outlines interim measures to address nitrate contamination in groundwater at the Burn Site, Sandia National Laboratories/New Mexico. The New Mexico Environment Department has required implementation of interim measures for nitrate-contaminated groundwater at the Burn Site. The purpose of interim measures is to prevent human or environmental exposure to nitrate-contaminated groundwater originating from the Burn Site. This Work Plan details a summary of current information about the Burn Site, interim measures activities for stabilization, and project management responsibilities to accomplish this purpose.

24 CFR 35.1330 - Interim controls.

Science.gov (United States)

2010-04-01

... Lead-Paint Hazard Evaluation and Hazard Reduction Activities § 35.1330 Interim controls. Interim..., cleanable covering or coating, such as metal coil stock, plastic, polyurethane, or linoleum. (3) Surfaces...

Presidential Transition: The Experience of Two Community College Interim Presidents

Science.gov (United States)

Thompson, Matthew D.

2010-01-01

The purpose of this qualitative case study was to understand the experiences of two community college interim presidents, their characteristics, and how they led institutions following an abrupt presidential departure. There were two fundamental questions framing this research study, 1. How do two interim community college presidents lead…

Effect of three natural pozzolans in portland cement hydration

Directory of Open Access Journals (Sweden)

Rahhal, V.

2003-03-01

Full Text Available Natural pozzolans have been used since ancient times and continues to be used today. The chemistry and morphological composition of natural pozzolans and their particle size distribution allows classifying them as more or less reactive pozzolan. In this research several techniques have been used to study the influence of pozzolan on portland cement hydration as much as to evaluate the mechanical and durable properties of concretes, mortars and pastes containing pozzolans. This paper describes the effect of incorporating three natural pozzolans to two cements with very different mineralogical composition. The techniques used were: conduction calorimetry and Fratini test. Results proved that pozzolanic activity and the acceleration and retardation of hydration reaction depend on the mineralogical composition of the portland cernent used. Effects of dilution, stimulation, acceleration or retardation reactions, behavior into areas of heat dissipation and pozzolanic activity depend on the percentage of pozzolan used and the age in which it has been analyzed.

El uso de las puzolanas naturales se remonta a la antigüedad, no obstante, actualmente continúa su utilización. La composición química y morfológica de las puzolanas naturales, sumado al tamaño de sus partículas, las califican como más o menos reactivas. En el estudio de las mismas, se han aplicado variadas técnicas para el análisis de sus interferencias en las reacciones de hidratación de los cementos portland; así como para la evaluación de las propiedades resistentes y duraderas que pueden conferirle a los hormigones, morteros o pastas de los que formen parte. Este trabajo versará sobre los efectos que produce la incorporación de tres puzolanas naturales a dos cementos portland de muy diferente composición mineralógica. Las técnicas aplicadas para su estudio han sido: la calorimetría de conducción y el ensayo de Fratini. Los resultados obtenidos permiten determinar

Tank Farm Interim Surface Barrier Materials And Runoff Alternatives Study

International Nuclear Information System (INIS)

Holm, M.J.

2009-01-01

This report identifies candidate materials and concepts for interim surface barriers in the single-shell tank farms. An analysis of these materials for application to the TY tank farm is also provided.

Solid waste burial grounds interim safety analysis

International Nuclear Information System (INIS)

Saito, G.H.

1994-01-01

This Interim Safety Analysis document supports the authorization basis for the interim operation and restrictions on interim operations for the near-surface land disposal of solid waste in the Solid Waste Burial Grounds. The Solid Waste Burial Grounds Interim Safety Basis supports the upgrade progress for the safety analysis report and the technical safety requirements for the operations in the Solid Waste Burial Grounds. Accident safety analysis scenarios have been analyzed based on the significant events identified in the preliminary hazards analysis. The interim safety analysis provides an evaluation of the operations in the Solid Waste Burial Grounds to determine if the radiological and hazardous material exposures will be acceptable from an overall health and safety standpoint to the worker, the onsite personnel, the public, and the environment

Solid waste burial grounds interim safety analysis

Energy Technology Data Exchange (ETDEWEB)

Saito, G.H.

1994-10-01

This Interim Safety Analysis document supports the authorization basis for the interim operation and restrictions on interim operations for the near-surface land disposal of solid waste in the Solid Waste Burial Grounds. The Solid Waste Burial Grounds Interim Safety Basis supports the upgrade progress for the safety analysis report and the technical safety requirements for the operations in the Solid Waste Burial Grounds. Accident safety analysis scenarios have been analyzed based on the significant events identified in the preliminary hazards analysis. The interim safety analysis provides an evaluation of the operations in the Solid Waste Burial Grounds to determine if the radiological and hazardous material exposures will be acceptable from an overall health and safety standpoint to the worker, the onsite personnel, the public, and the environment.

Reaction of rat subcutaneous tissue to mineral trioxide aggregate and Portland cement: a secondary level biocompatibility test.

Science.gov (United States)

Karanth, P; Manjunath, M K; Kuriakose, E S

2013-01-01

This secondary-level animal study was conducted to assess and compare the subcutaneous tissue reaction to implantation of white mineral trioxide aggregate (MTA) and white Portland cement. Polyethylene tubes filled with either freshly mixed white MTA (Group I) or white Portland cement (Group II) were implanted subcutaneously into 12 Wistar Albino rats. Each animal also received an empty polyethylene tube as the control (Group III). After 7, 14, 21 and 30 days, the implants, together with surrounding tissues were excised. Two pathologists blinded to the experimental procedure, evaluated sections taken from the biopsy specimens for the severity of the inflammatory response, calcification and the presence and thickness of fibrous capsule surrounding the implant. Statistical analysis was performed using the Cross-tabs procedure, Univariate analysis of the variance two-way and the Pearson product moment correlation to assess inter-rater variability between the two evaluators. At 7 days, there was no significant difference in the severity of inflammation between the control group, white MTA, and white Portland cement groups. In the 14 day, 21 day and 30 day test periods, control group had significantly less inflammation than white MTA and white Portland cement. There was no significant difference in the grading of inflammation between white MTA and white Portland cement. All materials exhibited thick capsule at 7 days and thin capsule by 30 days. Both white MTA and white Portland cement were not completely non-irritating at the end of 30 days as evidenced by the presence of mild inflammation. However, the presence of a thin capsule around the materials, similar to the control group, indicates good tissue tolerance. White MTA and white Portland cement seem to be materials of comparable biocompatibility.

1987 Federal interim storage fee study: A technical and economic analysis

International Nuclear Information System (INIS)

1987-09-01

This document is the latest in a series of reports that are published annually by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This information in the report, which was prepared by E.R. Johnson Associates under subcontract to PNL, will be used by the DOE to establish a payment schedule for interim storage of spent nuclear fuel under the Federal Interim Storage (FIS) Program, which was mandated by the Nuclear Waste Policy Act of 1982. The information in this report will be used to establish the schedule of charges for FIS services for the year commencing January 1, 1988. 13 tabs

1987 Federal interim storage fee study: A technical and economic analysis

Energy Technology Data Exchange (ETDEWEB)

1987-09-01

This document is the latest in a series of reports that are published annually by Pacific Northwest Laboratory (PNL) for the US Department of Energy (DOE). This information in the report, which was prepared by E.R. Johnson Associates under subcontract to PNL, will be used by the DOE to establish a payment schedule for interim storage of spent nuclear fuel under the Federal Interim Storage (FIS) Program, which was mandated by the Nuclear Waste Policy Act of 1982. The information in this report will be used to establish the schedule of charges for FIS services for the year commencing January 1, 1988. 13 tabs.

Lift : Special Needs Transportation in Portland, Oregon

Science.gov (United States)

1978-01-01

The report covers Portland, Oregon's Special Needs Transportation (SNT) project - the Lift - during its first year of operation. The purposes of this UMTA Service and Methods Demonstration (SMD) is to: (1) test a transit operator's ability to provide...

Modelling porewater chemistry in hydrated Portland cement

International Nuclear Information System (INIS)

Berner, U.R.

1987-01-01

Extensive employment of concrete is foreseen in radioactive waste repositories. A prerequisite for modelling the interactions between concrete and formation waters is characterization of the concrete system. Available experimental data from high pressure squeezing of cement pore-water indicate that, besides the high pH due to alkali hydroxide dissolution, cement composition itself influences the solubility determining solid phases. A model which simulates the hydration of Portland cement assuming complete hydration of the main clinker minerals is presented. The model also includes parameters describing the reactions between the cement and blending agents. Comparison with measured pore-water data generally gives a consistent picture and, as expected, the model gives correct predictions for pure Portland cements. For blended cements, the required additional parameters can, to some extent, be derived from pore-water analysis. 14 references, 1 figure, 4 tables

TWRS HLW interim storage facility search and evaluation

Energy Technology Data Exchange (ETDEWEB)

Calmus, R.B., Westinghouse Hanford

1996-05-16

The purpose of this study was to identify and provide an evaluation of interim storage facilities and potential facility locations for the vitrified high-level waste (HLW) from the Phase I demonstration plant and Phase II production plant. In addition, interim storage facilities for solidified separated radionuclides (Cesium and Technetium) generated during pretreatment of Phase I Low-Level Waste Vitrification Plant feed was evaluated.

33 CFR 100.1302 - Special Local Regulation, Annual Dragon Boat Races, Portland, Oregon.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Special Local Regulation, Annual Dragon Boat Races, Portland, Oregon. 100.1302 Section 100.1302 Navigation and Navigable Waters COAST... § 100.1302 Special Local Regulation, Annual Dragon Boat Races, Portland, Oregon. (a) Regulated area. All...

INFLUENCE OF BARIUM OXIDE ADDITIONS ON PORTLAND CLINKER

Directory of Open Access Journals (Sweden)

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.

EFFECT OF REHABILITATION DURING INTERIM STAY IN AALBORG MUNICIPALITY, DENMARK: A STUDY PROTOCOL

DEFF Research Database (Denmark)

Villumsen, Sidsel Maria Monrad; Villumsen, Morten

2016-01-01

Background: In the municipality of Aalborg, Denmark, the aim is to support citizens’ rehabilitation through training and learning in order to be self-reliant. This effort is supported at interim stays at the nursing homes [1]. A recent external report has outlined that citizen are highly satis ed...... are available in the systems, containing information on rehabilitation services rendered during interim stays. However, available data on the effect of the rehabilitation are currently unstructured in free-text, which impedes the assessment of rehabilitation effect and thereby the quality assurance. Objectives...... on rehabilitation of the citizen. The rehabilitation effect will be extracted from the free-text in the records. The free-text will be categorized into rehabilitation effects of i) deterioration, ii) no effect, iii) effect of rehabilitation, or iv) not possible to classify from the text. Results: This study...

Use of red mud as addition for portland cement mortars

International Nuclear Information System (INIS)

Ribeiro, D.V.; Morelli, M.R.

2011-01-01

The aim of the present research work was to investigate the possibility of adding red mud, an alkaline leaching waste that is obtained from bauxite during the Bayer process for alumina production, in the raw meal of Portland cement mortars. The red mud is classified as dangerous, according to NBR 10004/2004, and world while generation reached over 117 million tons/year. This huge production requires high consuming products to be used as incorporation matrix and we studied the influence of red mud addition on the characteristics of cement mortars and concrete. In this paper the properties of Portland cement mortars incorporating high amounts of red mud was evaluated: pH variation, fresh (setting time, workability or normal consistency and water retention), and hardened state (mechanical strength, capillary water absorption, density and apparent porosity). Results seem promising for red mud additions up to 20 wt%. (author)

PROJECT W-551 INTERIM PRETREATMENT SYSTEM PRECONCEPTUAL CANDIDATE TECHNOLOGY DESCRIPTIONS

Energy Technology Data Exchange (ETDEWEB)

MAY TH

2008-08-12

The Office of River Protection (ORP) has authorized a study to recommend and select options for interim pretreatment of tank waste and support Waste Treatment Plant (WTP) low activity waste (LAW) operations prior to startup of all the WTP facilities. The Interim Pretreatment System (IPS) is to be a moderately sized system which separates entrained solids and 137Cs from tank waste for an interim time period while WTP high level waste vitrification and pretreatment facilities are completed. This study's objective is to prepare pre-conceptual technology descriptions that expand the technical detail for selected solid and cesium separation technologies. This revision includes information on additional feed tanks.

Hospital waste ashes in Portland cement mortars

International Nuclear Information System (INIS)

Genazzini, C.; Zerbino, R.; Ronco, A.; Batic, O.; Giaccio, G.

2003-01-01

Nowadays, most concretes incorporate mineral additions such as pozzolans, fly ash, silica fume, blast furnace slag, and calcareous filler among others. Although the technological and economical benefits were the main reasons for the use of mineral additions, the prevention of environmental contamination by means of proper waste disposal becomes a priority. The chance of incorporating hospital waste ashes in Portland cement-based materials is presented here. Ash characterization was performed by chemical analysis, X-ray diffraction, radioactive material detection, and fineness and density tests. Conduction calorimetry and setting time tests were developed on pastes including ash contents from 0% to 100%. Mortars were prepared including ash contents up to 50% of cement. The results of setting time, temperature development, flexural and compressive strengths, water absorption, density, and leachability are analyzed. Results indicate that Portland cement systems could become an alternative for the disposal of this type of ashes

Interfacial morphology and domain configurations in 0-3 PZT-Portland cement composites

International Nuclear Information System (INIS)

Jaitanong, N.; Zeng, H.R.; Li, G.R.; Yin, Q.R.; Vittayakorn, W.C.; Yimnirun, R.; Chaipanich, A.

2010-01-01

Cement-based piezoelectric composites have attracted great attention recently due to their promising applications as sensors in smart structures. Lead zirconate titanate (PZT) and Portland cement (PC) composite were fabricated using 60% of PZT by volume. Scanning Electron Microscope and piezoresponse force microscope were used to investigate the morphology and domain configurations at the interfacial zone of PZT-Portland cement composites. Angular PZT ceramic grains were found to bind well with the cement matrix. The submicro-scale domains were clearly observed by piezoresponse force microscope at the interfacial regions between the piezoelectric PZT phase and Portland cement phase, and are clearer than the images obtained for pure PZT. This is thought to be due to the applied internal stress of cement to the PZT ceramic particle which resulted to clearer images.

78 FR 4381 - Foreign-Trade Zone 45-Portland, Oregon; Application for Reorganization and Expansion Under...

Science.gov (United States)

2013-01-22

... following sites: Site 1 (1,830 acres)--Rivergate Industrial Park, Port Terminal Nos. 5 and 6, and the... Way and NE Alderwood Road, Portland; Site 3 (254 acres)--Portland Ship Repair Yard, 5555 N. Channel...

76 FR 54206 - Gray Portland Cement and Clinker From Japan: Final Results of the Expedited Third Sunset Review...

Science.gov (United States)

2011-08-31

... DEPARTMENT OF COMMERCE International Trade Administration [A-588-815] Gray Portland Cement and... portland cement and clinker from Japan. As a result of this third sunset review, the Department finds that... initiation of the third sunset review of the antidumping duty order on gray portland cement and clinker from...

Potencialidades da metacaolinita e do tijolo queimado moído como substitutos parciais do cimento Portland Potentialities of metakaolin and crushed waste calcined clay brick as partial replacement of Portland cement

Directory of Open Access Journals (Sweden)

João de Farias Filho

2000-12-01

Full Text Available Avalia-se, neste trabalho, a potencialidade do uso da metacaolinita e dos resíduos de produção de tijolos cerâmicos queimados finamente moídos, como substitutos parciais do cimento Portland. Os materiais foram caracterizados física, química e mineralogicamente, além de determinado o índice de atividade pozolânica com cimento Portland. A evolução da resistência a compressão e a flexão das argamassas foi avaliada até as idades de, respectivamente, 365 e 208 dias. As porcentagens de substituição do cimento Portland, em peso, pelos materiais pozolânicos, variaram de 20 a 50%, enquanto o fator água/cimento variou de 0,37 a 0,45. Os resultados obtidos indicaram que a metacaolinita e o tijolo moído queimado possuem elevada atividade pozolânica e que a resistência a compressão, aos 28 dias, das argamassas mistas, foi superior à das argamassas de cimento Portland para os níveis de substituição e fatores água/cimento estudados. Um modelo matemático para predição da resistência à compressão das argamassas mistas é proposto com base em um desenho fatorial de experimentos.This paper evaluates the potentiality of metakaolin and crushed waste fired clay brick as cement replacement materials. They were characterised physically, chemically and mineralogically and their activity with Portland cement determined. The influence of the partial replacement of Portland cement on the development of compressive and flexural strength was evaluated until the age of, respectively, 365 and 208 days. The percentage of cement replacement, in weight, ranged from 20 to 50%, whereas the water/cement ratio ranged from 0.37 to 0.45. The results obtained show that the metakaolin and crushed calcined clay brick presented a good pozolanic activity and that the compressive strength of the blended mortars after 28 days of cure was higher than that observed for the reference Portland cement for all levels of cement replacement and water/cement ratio. A

Optimization of calcium chloride content on bioactivity and mechanical properties of white Portland cement

International Nuclear Information System (INIS)

Torkittikul, Pincha; Chaipanich, Arnon

2012-01-01

This research investigates the optimization of calcium chloride content on the bioactivity and mechanical properties of white Portland cement. Calcium chloride was used as an addition of White Portland cement at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by weight. Calcium chloride was dissolved in sterile distilled water and blended with White Portland cement using a water to cement ratio of 0.5. Analysis of the bioactivity and pH of white Portland cement pastes with calcium chloride added at various amounts was carried out in simulated body fluid. Setting time, density, compressive strength and volume of permeable voids were also investigated. The characteristics of cement pastes were examined by X-ray diffractometer and scanning electron microscope linked to an energy-dispersive X-ray analyzer. The result indicated that the addition of calcium chloride could accelerate the hydration of white Portland cement, resulting in a decrease in setting time and an increase in early strength of the pastes. The compressive strength of all cement pastes with added calcium chloride was higher than that of the pure cement paste, and the addition of calcium chloride at 8 wt.% led to achieving the highest strength. Furthermore, white Portland cement pastes both with and without calcium chloride showed well-established bioactivity with respect to the formation of a hydroxyapatite layer on the material within 7 days following immersion in simulated body fluid; white Portland cement paste with added 3%CaCl 2 exhibited the best bioactivity. - Highlights: ► Optimization CaCl 2 content on the bioactivity and mechanical properties. ► CaCl 2 was used as an addition at 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10% by weight. ► CaCl 2 resulted in a decrease in setting time and an increase in early strength. ► Addition of 3%CaCl 2 exhibited the optimum formation of hydroxyapatite.

Binding of chloride and alkalis in Portland cement systems

International Nuclear Information System (INIS)

Nielsen, Erik P.; Herfort, Duncan; Geiker, Mette R.

2005-01-01

A thermodynamic model for describing the binding of chloride and alkalis in hydrated Portland cement pastes has been developed. The model is based on the phase rule, which for cement pastes in aggressive marine environment predicts multivariant conditions, even at constant temperature and pressure. The effect of the chloride and alkalis has been quantified by experiments on cement pastes prepared from white Portland cements containing 4% and 12% C 3 A, and a grey Portland cement containing 7% C 3 A. One weight percent calcite was added to all cements. The pastes prepared at w/s ratio of 0.70 were stored in solutions of different Cl (CaCl 2 ) and Na (NaOH) concentrations. When equilibrium was reached, the mineralogy of the pastes was investigated by EDS analysis on the SEM. A well-defined distribution of chloride was found between the pore solution, the C-S-H phase, and an AFm solid solution phase consisting of Friedel's salt and monocarbonate. Partition coefficients varied as a function of iron and alkali contents. The lower content of alkalis in WPC results in higher chloride contents in the C-S-H phase. High alkali contents result in higher chloride concentrations in the pore solution

Contribución al estudio de los reacciones de hidratación del cemento portland por espectroscopia infrarroja II. Estudio de clínkeres y de cementos portland anhidros

Directory of Open Access Journals (Sweden)

Vázquez-Moreno, Tomás

1976-06-01

Full Text Available Not availableEn un artículo anterior (1 se dio cuenta de los trabajos realizados sobre la aplicación de la espectroscopia IR al estudio de las principales fases sintetizadas del clínker de cemento portland como fase previa al estudio de diversos clínkeres, obtenidos por nosotros en el laboratorio a partir de crudos industriales, y de distintos cementos portland comerciales anhidros.

Stabilization of chromium salt in ordinary portland cement

Indian Academy of Sciences (India)

Ordinary Portland cement (OPC) samples containing the chromium salt have been investigated using differential microcalorimetry, conductometry and Fourier transform infrared spectroscopic analysis. The effect of chromium on OPC hydration was evaluated by continuous observing of early hydration.

Rheological Properties of Very High-Strength Portland Cement Pastes: Influence of Very Effective Superplasticizers

Directory of Open Access Journals (Sweden)

Adriano Papo

2010-01-01

Full Text Available The influence of the addition of very effective superplasticizers, that are commercially available, employed for maximising the solid loading of very high-strength Portland cement pastes, has been investigated. Cement pastes were prepared from deionized water and a commercially manufactured Portland cement (Ultracem 52.5 R. Cement and water were mixed with a vane stirrer according to ASTM Standard C305. The 0.38 to 0.44 water/cement ratio range was investigated. Three commercial superplasticizing agents produced by Ruredil S.p.a. were used. They are based on a melamine resin (Fluiment 33 M, on a modified lignosulphonate (Concretan 200 L, and on a modified polyacrylate (Ergomix 1000. Rheological tests were performed at 25°C by using the rate controlled coaxial cylinder viscometer Rotovisko-Haake 20, system M5-osc., measuring device MV2P with serrated surfaces. The tests were carried out under continuous flow conditions. The results of this study were compared with those obtained in a previous article for an ordinary Portland cement paste.

EnviroAtlas - Portland, ME - Ecosystem Services by Block Group

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 146 block groups in Portland, Maine. Carbon attributes, temperature reduction,...

EnviroAtlas - Portland, OR - Ecosystem Services by Block Group

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset presents environmental benefits of the urban forest in 1176 block groups in Portland, Oregon. Carbon attributes, temperature reduction,...

Subsurface Interim Measures/Interim Remedial Action Plan/Environmental Assessment and Decision Document, Operable Unit No. 2

International Nuclear Information System (INIS)

1992-01-01

The subject Interim Measures/Interim Remedial Action plan/Environmental Assessment (IM/IRAP/EA) addresses residual free-phase volatile organic compound (VOC) contamination suspected in the subsurface within an area identified as Operable Unit No. 2 (OU2). This IM/IRAP/EA also addresses radionuclide contamination beneath the 903 Pad at OU2. Although subsurface VOC and radionuclide contamination on represent a source of OU2 ground-water contamination, they pose no immediate threat to public health or the environment. This IM/IRAP/EA identifies and evaluates interim remedial actions for removal of residual free-phase VOC contamination from three different subsurface environments at OU2. The term ''residual'' refers to the non-aqueous phase contamination remaining in the soil matrix (by capillary force) subsequent to the passage of non-aqueous or free-phase liquid through the subsurface. In addition to the proposed actions, this IM/IRAP/EA presents an assessment of the No Action Alternative. This document also considers an interim remedial action for the removal of radionuclides from beneath the 903 Pad

Biological evaluation of a new pulp capping material developed from Portland cement.

Science.gov (United States)

Negm, Ahmed M; Hassanien, Ehab E; Abu-Seida, Ashraf M; Nagy, Mohamed M

2017-03-02

This study evaluates the biological properties of a new pulp capping material developed from Portland cement. This study was conducted on 48 teeth in 4 dogs (12 teeth/dog). The dogs were classified into two equal groups (n=24 teeth) according to the evaluation period including: group A (3 weeks) and group B (3 months). Each group was further subdivided into three equal subgroups (n=8 teeth) according to the capping material including: subgroup 1: mineral trioxide aggregate (MTA), subgroup2: Portland cement+10% calcium hydroxide+20% bismuth oxide (Port Cal) and subgroup 3: Portland cement+bismuth oxide. After general anesthesia, a class V buccal cavity was prepared coronal to the gingival margin. After pulp exposure and hemostasis,the capping materials and glass ionomer filling were placed on the exposure sites. All histopathological findings, inflammatory cell count and dentin bridge formation were recorded. Data were analyzed statistically. After 3 months, the histopathological picture of the pulp in subgroup 1 showed normal pulp, continuous odontoblastic layer and complete dentin bridge formation while subgroup 2 showed partial and complete dentin bridge over a normal and necrotic pulps. Subgroup 3 showed loss of normal architecture, areas of necrosis, complete, or incomplete dentin bridge formation, attached and detached pulp stones and fatty degeneration in group B. For group A, MTA subgroup showed the least number of inflammatory cell infiltrate followed by Port Cal subgroup. While subgroup 3 showed the highest number of inflammatory cell infiltrate. For group B, the mean inflammatory cell count increased with the three tested materials with no statistical difference. Regarding dentin bridge formation at group A, no significant differences was found between subgroups, while at group B, MTA subgroup exhibited significantly higher scores than other subgroups. In conclusion, addition of calcium hydroxide to Portland cement improves the dentin bridge formation

Application of probabilistic risk assessment: Evaluating remedial alternatives at the Portland Harbor Superfund Site, Portland, Oregon, USA.

Science.gov (United States)

Ruffle, Betsy; Henderson, James; Murphy-Hagan, Clare; Kirkwood, Gemma; Wolf, Frederick; Edwards, Deborah A

2018-01-01

A probabilistic risk assessment (PRA) was performed to evaluate the range of potential baseline and postremedy health risks to fish consumers at the Portland Harbor Superfund Site (the "Site"). The analysis focused on risks of consuming fish resident to the Site containing polychlorinated biphenyls (PCBs), given that this exposure scenario and contaminant are the primary basis for US Environmental Protection Agency's (USEPA's) selected remedy per the January 2017 Record of Decision (ROD). The PRA used probability distributions fit to the same data sets used in the deterministic baseline human health risk assessment (BHHRA) as well as recent sediment and fish tissue data to evaluate the range and likelihood of current baseline cancer risks and noncancer hazards for anglers. Areas of elevated PCBs in sediment were identified on the basis of a geospatial evaluation of the surface sediment data, and the ranges of risks and hazards associated with pre- and postremedy conditions were calculated. The analysis showed that less active remediation (targeted to areas with the highest concentrations) compared to the remedial alternative selected by USEPA in the ROD can achieve USEPA's interim risk management benchmarks (cancer risk of 10 -4 and noncancer hazard index [HI] of 10) immediately postremediation for the vast majority of subsistence anglers that consume smallmouth bass (SMB) fillet tissue. In addition, the same targeted remedy achieves USEPA's long-term benchmarks (10 -5 and HI of 1) for the majority of recreational anglers. Additional sediment remediation would result in negligible additional risk reduction due to the influence of background. The PRA approach applied here provides a simple but adaptive framework for analysis of risks and remedial options focused on variability in exposures. It can be updated and refined with new data to evaluate and reduce uncertainty, improve understanding of the Site and target populations, and foster informed remedial decision

Silica fume effect on retention characteristics of portland cement for uranium (VI)

International Nuclear Information System (INIS)

Tan Hongbin; Ma Xiaoling; Li Yuxiang

2005-01-01

With simulated groundwater as leachant, the retention capabilities of the portland cement, which contains different amount of silica fume, are investigated under 25 degree C and 42 days. The results indicate that silica fume can improve the retention capabilities of portland cement for uranium. When the cement contains 15% silica fume, the diffusion coefficient is 7 x 10 -3 cm 3 · -1 . It is only 5.5% of the cement without containing fume. (authors)

Mineral Trioxide Aggregate and Portland Cement for Direct Pulp Capping in Dog: A Histopathological Evaluation

Directory of Open Access Journals (Sweden)

Maryam Bidar

2014-09-01

Full Text Available Background and aims. Mineral trioxide aggregate and calcium hydroxide are considered the gold standard pulp-capping materials. Recently, Portland cement has been introduced with properties similar to those of mineral trioxide aggregate. His-topathological effects of direct pulp capping using mineral trioxide aggregate and Portland cements on dog dental pulp tis-sue were evaluated in the present study. Materials and methods. This histopatological study was carried out on 64 dog premolars. First, the pulp was exposedwith a sterile bur. Then, the exposed pulp was capped with white or gray mineral trioxide aggregates and white or gray Port-land cements in each quadrant and sealed with glass-ionomer. The specimens were evaluated under a light microscope after 6 months. Statistical analysis was carried out using Kruskal-Wallis test. Statistical significance was defined at α=5%. Results. There was no acute inflammation in any of the specimens. Chronic inflammation in white and gray mineral triox-ide aggregates and white and gray Portland cements was reported to be 45.5%, 27.3%, 57.1% and 34.1%, respectively. Al-though the differences were not statistically significant, severe inflammation was observed mostly adjacent to white mineral trioxide aggregate. The largest extent of increased vascularization (45% and the least increase in fibrous tissue were ob-served adjacent to white mineral trioxide aggregate, with no significant differences. In addition, the least calcified tissue formed adjacent to white mineral trioxide aggregate, although the difference was not significant. Conclusion. The materials used in this study were equally effective as pulp protection materials following direct pulp cap-ping in dog teeth.

New York State interim waste management cost evaluation

International Nuclear Information System (INIS)

Ma, M.S.; Watts, R.J.; Jorgensen, J.R.; Rochester Gas and Electric Corp., NY)

1985-01-01

The purpose of this study is to investigate and quantify the comparative costs associated with including or excluding Class A utility wastes at a centralized interim waste management facility in New York State. The objective of the study is to assess the unit costs and total statewide costs associated with two distinct scenarios: (1) the case where non-utility Class A LLRW is received, incinerated and stored at the centralized interim facility, and utility Class A wastes are held without incineration at respective nuclear power plant interim onsite facilities without incineration; and (2) the alternative case where both utility and non-utility Class A wastes are accepted, incinerated and stored at the centralized facility. Unit costs to waste generators are estimated for each of the two cases described. This is followed by an estimation of the statewide cost impact to the public. The cost impact represents the cost differential resulting from the exclusion of utility Class A waste from the centralized NYS interim waste management facility. The principal factors comprising the cost differential include (1) higher unit disposal fees charged to non-utility waste generators, which are passed along in the costs of products and services; and (2) costs to utilities due to construction of additional onsite storage capacity, which in turn are charged to electric rate payers

Addendum to IFMIF-CDA interim report

Energy Technology Data Exchange (ETDEWEB)

Maekawa, Hiroshi; Ida, Mizuho [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; eds.

1996-08-01

During the second IFMIF-CDA Design Integration Workshop, the conceptual design and contents of `IFMIF-CDA Interim Report` were examined and discussed at both general and group meetings. Based on these discussion, the final IFMIF-CDA Report will be modified from the `Interim Report`. This report describes the outline of these modification. (author)

Addendum to IFMIF-CDA interim report

International Nuclear Information System (INIS)

Maekawa, Hiroshi; Ida, Mizuho

1996-08-01

During the second IFMIF-CDA Design Integration Workshop, the conceptual design and contents of 'IFMIF-CDA Interim Report' were examined and discussed at both general and group meetings. Based on these discussion, the final IFMIF-CDA Report will be modified from the 'Interim Report'. This report describes the outline of these modification. (author)

Healing of apical rarefaction of three nonvital open apex anterior teeth using a white portland cement apical plug

Directory of Open Access Journals (Sweden)

Amitabha Chakraborty

2012-01-01

Full Text Available The major challenge of performing root canal treatment in an open apex pulp-less tooth is to obtain a good apical seal. MTA has been successfully used to achieve a good apical seal, wherein the root canal obturation can be done immediately. MTA and White Portland Cement has been shown similarity in their physical, chemical and biological properties and has also shown similar outcome when used in animal studies and human trials. In our study, open apex of three non vital upper central incisors has been plugged using modified white Portland cement. 3 to 6 months follow up revealed absence of clinical symptoms and disappearance of peri-apical rarefactions. The positive clinical outcome may encourage the future use of white Portland cement as an apical plug material in case of non vital open apex tooth as much cheaper substitute of MTA.

Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone

DEFF Research Database (Denmark)

Moesgaard, M; Poulsen, Søren Lundsted; Herfort, D

2012-01-01

M. MOESGAARD, S.L. POULSEN, D. HERFORT, M. STEENBERG, L.F. KIRKEGAARD, J. SKIBSTED, Y. YUE, Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone, Journal of the American Ceramic Society 95, 403 – 409 (2012).......M. MOESGAARD, S.L. POULSEN, D. HERFORT, M. STEENBERG, L.F. KIRKEGAARD, J. SKIBSTED, Y. YUE, Hydration of Blended Portland Cements Containing Calcium-Aluminosilicate Glass Powder and Limestone, Journal of the American Ceramic Society 95, 403 – 409 (2012)....

Sustainable Solutions for Nuclear used Fuels Interim Storage

International Nuclear Information System (INIS)

Arslan, Marc; Favet, Dominique; Issard, Herve; Le Jemtel, Amaury; Drevon, Caroline

2014-01-01

AREVA has a unique experience in providing sustainable solutions for used fuel management, fitted with the needs of different customers in the world and with regulation in different countries. These solutions entail both recycling and interim storage technologies. In a first part, we will describe the various types of solutions for Interim Storage of UNF that have been implemented around the world for interim storage at reactor or centralized Pad solution in canisters dry storage, vault type storages for dry storage, dry storage of transportation casks (dual purpose) pools for wet storage, The experience for all these different families of interim storages in which AREVA is involved is extensive and will be discussed with respect to the new challenges: increase of the duration of the interim storage (long term interim storage) increase of burn up of the fuels In a second part of the presentation, special recycling features will be presented. In that case, interim storage of the used fuels is ensured in pools. This provides in the long term good conditions for the behaviour of the fuel and its retrievability. With recycling, the final waste (Universal Canister of vitrified fission products and compacted hulls and end pieces): is stable and licensed in many countries for the final disposal (France, UK, Belgium, NL, Switzerland, Germany, Japan, upcoming: Spain, Australia, Italy). Presents neither safety criticality risks nor proliferation risks (AREVA conditioned HLW and LL-ILW are free of IAEA safeguard constraints thanks to AREVA process high recovery and purification yields). It can therefore be safely stored in interim storage for more than 100 years before final disposal. Some economic considerations will also be discussed. In particular, in the case of long term interim storage of used fuels, there are growing uncertainties regarding the future needs of repackaging and transportation, which can result in future cost overruns. Meanwhile, in the recycling policy

Evolution of porosity in a Portland cement paste studied through positron annihilation lifetime spectroscopy

International Nuclear Information System (INIS)

Consolati, G.; Quasso, F.

2003-01-01

Positron annihilation lifetime spectroscopy experiments were carried out in an ordinary Portland cement paste characterized by a water-to-cement ratio w/c=0.8, in order to monitor the porosity of the paste. It was found that ortho-positronium intensity is a suitable quantity to this purpose, being sensitive to the amount of water contained in the pores. The experimental data show good agreement with the porosity calculated according to the Powers' thin filmsodel

Regional economic impact assessment: Evaluating remedial alternatives for the Portland Harbor Superfund Site, Portland, Oregon, USA.

Science.gov (United States)

Harrison, David; Coughlin, Conor; Hogan, Dylan; Edwards, Deborah A; Smith, Benjamin C

2018-01-01

The present paper describes a methodology for evaluating impacts of Superfund remedial alternatives on the regional economy in the context of a broader sustainability evaluation. Although economic impact methodology is well established, some applications to Superfund remedial evaluation have created confusion because of seemingly contradictory results. This confusion arises from failure to be explicit about 2 opposing impacts of remediation expenditures: 1) positive regional impacts of spending additional money in the region and 2) negative regional impacts of the need to pay for the expenditures (and thus forgo other expenditures in the region). The present paper provides a template for economic impact assessment that takes both positive and negative impacts into account, thus providing comprehensive estimates of net impacts. The paper also provides a strategy for identifying and estimating major uncertainties in the net impacts. The recommended methodology was applied at the Portland Harbor Superfund Site, located along the Lower Willamette River in Portland, Oregon, USA. The US Environmental Protection Agency (USEPA) developed remedial alternatives that it estimated would cost up to several billion dollars, with construction durations possibly lasting decades. The economic study estimated regional economic impacts-measured in terms of gross regional product (GRP), personal income, population, and employment-for 5 of the USEPA alternatives relative to the "no further action" alternative. Integr Environ Assess Manag 2018;14:32-42. © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC). © 2017 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

The Nord interim store

International Nuclear Information System (INIS)

Leushacke, D.F.; Rittscher, D.

1996-01-01

In line with the decision taken in 1990 to shut down and decommission the Greifswald and Rheinsberg Nuclear Power Stations, the waste management concept of the Energiewerke Nord is based on direct and complete decommissioning of the six shut down reactor units within the next fifteen years. One key element of this concept is the construction and use of the Zwischenlager Nord (Nord Interim Store, ZLN) for holding the existing nuclear fuels and for interim and decay storage of the radioactive materials arising in decommissioning and demolition. The owner and operator of the store is Energiewerke Nord GmbH. The interim store has the functions of a processing and Energiewerke Nord GmbH. The interim store has the functions of a processing and treatment station and buffer store for the flows of residues arising. As a radioactive waste management station, it accommodates nuclear fuels, radioactive waste or residues which are not treated any further. It is used as a buffer store to allow the materials accumulating in disassembly to be stored temporarily before or after treatment in order to ensure continuous loading of the treatment plants. When operated as a processing station, the ZLN is able to handle nearly all types of radioactive waste and residues arising, except for nuclear fuels. These installations allow the treatment of radioactive residues to be separated from the demolition work both physically and in time. The possibilities of interium storage and buffer storage of untreated waste and waste packages make for high flexibility in logistics and waste management strategy. (orig.) [de

Fit of interim crowns fabricated using photopolymer-jetting 3D printing.

Science.gov (United States)

Mai, Hang-Nga; Lee, Kyu-Bok; Lee, Du-Hyeong

2017-08-01

The fit of interim crowns fabricated using 3-dimensional (3D) printing is unknown. The purpose of this in vitro study was to evaluate the fit of interim crowns fabricated using photopolymer-jetting 3D printing and to compare it with that of milling and compression molding methods. Twelve study models were fabricated by making an impression of a metal master model of the mandibular first molar. On each study model, interim crowns (N=36) were fabricated using compression molding (molding group, n=12), milling (milling group, n=12), and 3D polymer-jetting methods. The crowns were prepared as follows: molding group, overimpression technique; milling group, a 5-axis dental milling machine; and polymer-jetting group using a 3D printer. The fit of interim crowns was evaluated in the proximal, marginal, internal axial, and internal occlusal regions by using the image-superimposition and silicone-replica techniques. The Mann-Whitney U test and Kruskal-Wallis tests were used to compare the results among groups (α=.05). Compared with the molding group, the milling and polymer-jetting groups showed more accurate results in the proximal and marginal regions (P3D printing significantly enhanced the fit of interim crowns, particularly in the occlusal region. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Evaluation of dynamic elasticity module in samples of Portland (type 1) cement paste exposed to neutronic irradiation

International Nuclear Information System (INIS)

Rosa Junior, A.A.; Lucki, G.

1986-01-01

The fast neutron radiation effects and temperature on Portland cement are studied. The Dynamic Elasticity Module (Ed) in samples of Portland cement paste was evaluated. Ultrassonic technics were applied (resonance frequency and pulse velocity). The samples were irradiated with fast neutrons to fluence of 7,2 x 10 18 n/cm 2 (E approx. 1 MeV), at temperature of 120 + - 5 0 C, due to gamma heating. This temperature was simulated in laboratory in a microwave oven. (Author) [pt

X-ray diffractometry of steam cured ordinary Portland and blast-furnace-slag cements

International Nuclear Information System (INIS)

Camarini, G.; Djanikian, J.G.

1994-01-01

This work studies some aspects of the phases produced by hydration of ordinary and blast-furnace-slag cements, at normal conditions and steam cured (60 and 95 0 C), using an X-ray diffraction technique. The blast-furnace-slag cement was a mixture of 50% of ordinary Portland cement and 50% of blast-furnace-slag (separately grinding). After curing the X-ray diffraction reveals that, in relation to ordinary Portland cement, the main phases in blast-furnace-slag cement are hydrated silicates and aluminates, hydro garnet, etringitte and mono sulphate. After steam curing the hydration of blast-furnace-slag cement proceeds. This is a result of the slag activation by the curing temperature. (author). 8 refs., 3 figs., 1 tab

Interim storage of radioactive waste packages

International Nuclear Information System (INIS)

1998-01-01

This report covers all the principal aspects of production and interim storage of radioactive waste packages. The latest design solutions of waste storage facilities and the operational experiences of developed countries are described and evaluated in order to assist developing Member States in decision making and design and construction of their own storage facilities. This report is applicable to any category of radioactive waste package prepared for interim storage, including conditioned spent fuel, high level waste and sealed radiation sources. This report addresses the following issues: safety principles and requirements for storage of waste packages; treatment and conditioning methods for the main categories of radioactive waste; examples of existing interim storage facilities for LILW, spent fuel and high level waste; operational experience of Member States in waste storage operations including control of storage conditions, surveillance of waste packages and observation of the behaviour of waste packages during storage; retrieval of waste packages from storage facilities; technical and administrative measures that will ensure optimal performance of waste packages subject to various periods of interim storage

Quantitative study of Portland cement hydration by X-ray diffraction/Rietveld analysis and independent methods

International Nuclear Information System (INIS)

Scrivener, K.L.; Fuellmann, T.; Gallucci, E.; Walenta, G.; Bermejo, E.

2004-01-01

X-ray diffraction (XRD) is a powerful technique for the study of crystalline materials. The technique of Rietveld refinement now enables the amounts of different phases in anhydrous cementitious materials to be determined to a good degree of precision. This paper describes the extension of this technique to a pilot study of the hydration of a typical Portland cement. To validate this XRD-Rietveld analysis technique, its results were compared with independent measures of the same materials by the analysis of backscattered electron images (BSE/IA) and thermogravimetric analysis (TGA). In addition, the internal consistency of the measurements was studied by comparing the XRD estimates of the amounts of hydrates formed with the amounts expected to form from the XRD estimates of the amounts of anhydrous materials reacted

High-volume natural volcanic pozzolan and limestone powder as partial replacements for portland cement in self-compacting and sustainable concrete

KAUST Repository

Celik, Kemal; Jackson, Marie D.; Mancio, Mauricio; Meral, Cagla; Emwas, Abdul-Hamid M.; Mehta, P. Kumar; Monteiro, Paulo José Meleragno

2014-01-01

A laboratory study demonstrates that high volume, 45% by mass replacement of portland cement (OPC) with 30% finely-ground basaltic ash from Saudi Arabia (NP) and 15% limestone powder (LS) produces concrete with good workability, high 28-day compressive strength (39 MPa), excellent one year strength (57 MPa), and very high resistance to chloride penetration. Conventional OPC is produced by intergrinding 95% portland clinker and 5% gypsum, and its clinker factor (CF) thus equals 0.95. With 30% NP and 15% LS portland clinker replacement, the CF of the blended ternary PC equals 0.52 so that 48% CO2 emissions could be avoided, while enhancing strength development and durability in the resulting self-compacting concrete (SCC). Petrographic and scanning electron microscopy (SEM) investigations of the crushed NP and finely-ground NP in the concretes provide new insights into the heterogeneous fine-scale cementitious hydration products associated with basaltic ash-portland cement reactions. © 2013 Published by Elsevier Ltd.

X-ray diffractometry of steam cured ordinary Portland and blast-furnace-slag cements; Difratometria de raios X de pastas de cimento Portland comum e de alto-forno submetidas a cura termica

Energy Technology Data Exchange (ETDEWEB)

Camarini, G [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia; Djanikian, J G [Sao Paulo Univ., SP (Brazil). Escola Politecnica

1994-12-31

This work studies some aspects of the phases produced by hydration of ordinary and blast-furnace-slag cements, at normal conditions and steam cured (60 and 95{sup 0} C), using an X-ray diffraction technique. The blast-furnace-slag cement was a mixture of 50% of ordinary Portland cement and 50% of blast-furnace-slag (separately grinding). After curing the X-ray diffraction reveals that, in relation to ordinary Portland cement, the main phases in blast-furnace-slag cement are hydrated silicates and aluminates, hydro garnet, etringitte and mono sulphate. After steam curing the hydration of blast-furnace-slag cement proceeds. This is a result of the slag activation by the curing temperature. (author). 8 refs., 3 figs., 1 tab.

Quantitative study on the effect of high-temperature curing at an early age on strength development of concrete. Experiment with mortar using moderate-heat portland cement

International Nuclear Information System (INIS)

Sugiyama, Hisashi; Chino, Shigeo

1999-01-01

The effect of high-temperature curing at an early age on the strength development of concrete using moderate-heat portland cement was quantitatively studied. High-temperature curing conditions were set so as to give systematic variations in the temperature-time factors. As a result, the integrated value of curing temperature during the period having a significant effect on the strength development was proposed as a parameter that expressed the degree of high-temperature curing. The effect of high-temperature curing on the strength development of concrete using moderate-heat portland cement could be exactly predicted with the integrated value of curing temperature during the period from 0 to 3 days. (author)

Immobilized high-level waste interim storage alternatives generation and analysis and decision report

International Nuclear Information System (INIS)

CALMUS, R.B.

1999-01-01

This report presents a study of alternative system architectures to provide onsite interim storage for the immobilized high-level waste produced by the Tank Waste Remediation System (TWRS) privatization vendor. It examines the contract and program changes that have occurred and evaluates their impacts on the baseline immobilized high-level waste (IHLW) interim storage strategy. In addition, this report documents the recommended initial interim storage architecture and implementation path forward

Presence of arsenic in different types of MTA and white and gray Portland cement.

Science.gov (United States)

Monteiro Bramante, Clóvis; Demarchi, Ana Claudia Cardoso Oliveira; de Moraes, Ivaldo Gomes; Bernadineli, Norberti; Garcia, Roberto Brandão; Spångberg, Lars S W; Duarte, Marco Antonio Hungaro

2008-12-01

The presence of arsenic in various types of mineral trioxide aggregate (MTA) and Portland cements were evaluated to verify if they comply with the ISO-recommended limit for water-based cements of 2 mg arsenic/kg material. An amount of 5 mL of hydrochloric acid was added to 2 g each of MTA and Portland cement to be analyzed. After 15 minutes, the material was filtered and the volume of supernatant was diluted with reagent-grade water up to 40 mL. Atomic absorption spectrophotometry readings were performed in triplicate. The following mean values were obtained: CPM (Egeo, Buenos Aires, Argentina) 11.06 mg/kg; CPM sealer (Egeo) 10.30 mg/kg; MTA-Obtura (Angelus, Londrina, PR, Brazil) 0.39 mg/kg; Experimental MTA: 10.30 mg/kg; White MTA-Angelus (Angelus) 1.03 mg/kg; Gray MTA-Angelus (Angelus) 5.91 mg/kg; ProRoot-MTA (Dentsply/Tulsa Dental Specialties, Tulsa, OK) 5.25 mg/kg; Gray Portland cement (Votorantim Cimentos, Cubatão, SP, Brazil): 34.27 mg/kg; and White Portland cement (Cimento Rio Branco, Rio de Janeiro, RJ, Brazil) 0.52 mg/kg. All tested materials presented arsenic in their composition. The form of arsenic was not analyzed nor the toxicity of the arsenic found. Only MTA-Obtura, White MTA-Angelus, and White Portland cement presented arsenic levels below the limit set in the ISO 9917-1 standard.

Research on the nanolevel influence of surfactants on structure formation of the hydrated Portland cement compositions

Directory of Open Access Journals (Sweden)

Guryanov Alexander

2016-01-01

Full Text Available The research of the structure formation process on a nanolevel of the samples of hydrated Portland cement compositions containing the modifying additives has been conducted with the help of small angle neutron scattering method. Carbonate and aluminum alkaline slimes as well as the complex additives containing surfactants were used as additives. The influence of slimes and surfactants on structural parameters change of Portland cement compositions of the average size of the disseminating objects, fractal dimension samples is considered. These Portland cement compositions are shown to be fractal clusters.

Evaluation of physico-chemical properties of Portland cements and MTA

Directory of Open Access Journals (Sweden)

Jorge Luis Gonçalves

2010-09-01

Full Text Available The purpose of this study was to evaluate the hydrogenionic potential and electrical conductivity of Portland cements and MTA, as well as the amount of arsenic and calcium released from these materials. In Teflon molds, samples of each material were agitated and added to plastic flasks containing distilled water for 3, 24, 72 and 168 h. The results were analyzed with a Kruskal-Wallis non-parametric test for global comparisons and a Dunn-Tukey test for pairwise comparisons. The results revealed no significant differences in the pH of the materials (p > 0.05. The electrical conductivity of the cements were not statistically different (p > 0.05. White non-structural cement and MTA BIO released the largest amount of calcium ions into solution (p 0.05. The results indicated that the physico-chemical properties of Portland cements and MTA were similar. Furthermore, all materials produced an alkaline environment and can be considered safe for clinical use because arsenic was not released. The electrical conductivity and the amount of calcium ions released into solution increased over time.

Evaluation of physico-chemical properties of Portland cements and MTA.

Science.gov (United States)

Gonçalves, Jorge Luis; Viapiana, Raqueli; Miranda, Carlos Eduardo Saraiva; Borges, Alvaro Henrique; Cruz Filho, Antônio Miranda da

2010-01-01

The purpose of this study was to evaluate the hydrogenionic potential and electrical conductivity of Portland cements and MTA, as well as the amount of arsenic and calcium released from these materials. In Teflon molds, samples of each material were agitated and added to plastic flasks containing distilled water for 3, 24, 72 and 168 h. The results were analyzed with a Kruskal-Wallis non-parametric test for global comparisons and a Dunn-Tukey test for pairwise comparisons. The results revealed no significant differences in the pH of the materials (p > 0.05). The electrical conductivity of the cements were not statistically different (p > 0.05). White non-structural cement and MTA BIO released the largest amount of calcium ions into solution (p 0.05). The results indicated that the physico-chemical properties of Portland cements and MTA were similar. Furthermore, all materials produced an alkaline environment and can be considered safe for clinical use because arsenic was not released. The electrical conductivity and the amount of calcium ions released into solution increased over time.

Yucca Mountain socioeconomic project: An interim report on the State of Nevada socioeconomic studies

International Nuclear Information System (INIS)

1989-06-01

The State of Nevada formally initiated a study of the socioeconomic impacts of a proposed high-level nuclear waste repository at Yucca Mountain in southern Nevada in 1986 after the Nevada site had been chosen as a potential waste disposal site. The State and affected local governments that participated in the development of the study recognized that the effort would need to go well beyond what is traditionally considered adequate for socioeconomic impact assessment because of the unique nature of the repository project. This Interim Report is a report on work in progress and presents findings from the research to date on the potential consequences of a repository for the citizens of Nevada. The research and findings in the Report have been subjected to rigorous peer review as part of the state's effort to insure independent, objective analysis that meets the highest professional standards. The basic research effort will continue through June 1990 and will enable the state to refine and clarify the findings presented in this Interim Report

Federal interim storage fee study for civilian spent nuclear fuel: a technical and economical analysis

International Nuclear Information System (INIS)

1983-07-01

This report describes the study conducted by the Department of Energy (the Department) regarding payment charges for the federal interim storage (FIS) of spent fuel and presents the details of the study results. It describes the selection of a methodology for calculating a FIS fee schedule, sets forth the estimates of cost for construction and operation of FIS facilities, provides a range of estimates for the fee for FIS services, and identifies special contractual considerations associated with providing FIS services to authorized users. The fee is structured for a range of spent fuel capacities because of uncertainties regarding the schedule of availability and amount of spent fuel that may require and qualify for FIS. The results set forth in the report were used as a basis for development of the report entitled Payment Charges for Federal Interim Storage of Spent Nuclear Fuel from Civilian Nuclear Power Plants in the United States, dated July 1983

76 FR 58790 - Notice of Interim Approval

Science.gov (United States)

2011-09-22

... to the customers. Rate Scenario 3--Original Cumberland Marketing Policy The third rate alternative... an interim basis to the customers. Rate Scenario 3--Original Cumberland Marketing Policy The third... allocated on an interim basis to the customers. Rate Scenario 3--Original Cumberland Marketing Policy The...

Arsenic Encapsulation Using Portland Cement With Ferrous Sulfate/Lime And Terra-BondTM Technologies - Microcharacterization And Leaching Studies

Science.gov (United States)

This work reports the results of an investigation on the treatment and encapsulation of arsenic-containing materials by Portland cement with ferrous sulfate and lime (PFL) and Terra-BondTM, a commercially available patented technology. The arsenic materials treated we...

The Interim Financial Statements: The Case of Greece

OpenAIRE

Rogdaki, E.I.; Kazantzis, Ch.

1999-01-01

The following paper refers to the accounting and auditing issues which emerge in the preparation of the interim financial statements of the companies: Firstly, the interim financial statements are defined as being the financial statements that provide useful information about the financial position and the financial results of a company which are realized and accrued during the fiscal year. The interim financial statements can be prepared on a monthly basis, on a quarterly basis or covering a...

Alternatieven voor Portland Cement in ontwikkelingslanden onderzocht : continue-kalkoven maakt toepassing van kalk pozzolaan cement mogelijk

NARCIS (Netherlands)

Egmond - de Wilde De Ligny, van E.L.C.; Jongsma, Ivo

1995-01-01

In de discussie over bouwmaterialen in ontwikkelingslanden wordt vaak gepleit voor alternatieven voor Portland Cement. De productie van Portland Cement is kapitaal- en energie-intensief en draagt weinig bij aan de ontwikkeling van deze landen. De klein schaliger productie van alternatieven voor

Exploratory characterization of volcanic ash sourced from Uganda as a pozzolanic material in portland cement concrete

NARCIS (Netherlands)

Buregyeya, A.; Quercia Bianchi, G.; Spiesz, P.R.; Florea, M.V.A.; Nassingwa, R.; Uzoegbo, H.C.; Schmidt, W.

2013-01-01

The need for alternative cementing materials to ordinary Portland cement (OPC) has promoted characterization research on pozzolana as an important ingredient in cement production. In Uganda, natural pozzolana application in cement production is done by only two producers of Portland cement and at a

Effectiveness of interim remedial actions at a radioactive waste facility

International Nuclear Information System (INIS)

Devgun, J.S.; Beskid, N.J.; Peterson, J.M.; Seay, W.M.; McNamee, E.

1989-01-01

Over the past eight years, several interim remedial actions have been taken at the Niagara Falls Storage Site (NFSS), primarily to reduce radon and gamma radiation exposures and to consolidate radioactive waste into a waste containment facility. Interim remedial actions have included capping of vents, sealing of pipes, relocation of the perimeter fence (to limit radon risk), transfer and consolidation of waste, upgrading of storage buildings, construction of a clay cutoff wall (to limit the potential groundwater transport of contaminants), treatment and release of contaminated water, interim use of a synthetic liner, and emplacement of an interim clay cap. An interim waste containment facility was completed in 1986. 6 refs., 3 figs

City of Portland: Businesses for an environmentally sustainable tomorrow

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-12-01

The sustainable business development program in Portland (OR) is known as BEST. BEST stands for Businesses for an Environmentally Sustainable Tomorrow. The Portland Energy Office operates BEST as a {open_quotes}one-stop service center{close_quotes} for business owners and managers. BEST provides information and assistance on resource efficient buildings and business practices. The results of BEST`s two years of operation have been generally impressive. Nearly 150 new or expanding businesses have been connected with utility design assistance programs. Businesses have also received assistance with water conservation, telecommuting, construction debris recycling, and alternative fuel vehicles. BEST has received local and national publicity and BEST services have been the topic at more than a dozen conferences, meetings, or other speaking engagements. A guidebook for communities wishing to start a similar program will be available in early 1996.

Predictive probability methods for interim monitoring in clinical trials with longitudinal outcomes.

Science.gov (United States)

Zhou, Ming; Tang, Qi; Lang, Lixin; Xing, Jun; Tatsuoka, Kay

2018-04-17

In clinical research and development, interim monitoring is critical for better decision-making and minimizing the risk of exposing patients to possible ineffective therapies. For interim futility or efficacy monitoring, predictive probability methods are widely adopted in practice. Those methods have been well studied for univariate variables. However, for longitudinal studies, predictive probability methods using univariate information from only completers may not be most efficient, and data from on-going subjects can be utilized to improve efficiency. On the other hand, leveraging information from on-going subjects could allow an interim analysis to be potentially conducted once a sufficient number of subjects reach an earlier time point. For longitudinal outcomes, we derive closed-form formulas for predictive probabilities, including Bayesian predictive probability, predictive power, and conditional power and also give closed-form solutions for predictive probability of success in a future trial and the predictive probability of success of the best dose. When predictive probabilities are used for interim monitoring, we study their distributions and discuss their analytical cutoff values or stopping boundaries that have desired operating characteristics. We show that predictive probabilities utilizing all longitudinal information are more efficient for interim monitoring than that using information from completers only. To illustrate their practical application for longitudinal data, we analyze 2 real data examples from clinical trials. Copyright © 2018 John Wiley & Sons, Ltd.

Structure investigations on Portland cement paste by small angle neutron scattering

International Nuclear Information System (INIS)

Dragolici, C.A.; Lin, A.

2004-01-01

Hydrated Portland cement is a very complex material. Cement paste consists of many crystalline and non-crystalline phases in various ranges of sizes (μm and nm scale). The crystalline phases are embedded in amorphous phases of hydration products. We investigated the structural changes of hydrating phases in a time interval up to 18 days, at Budapest Neutron Center's SANS spectrometer. The small angle neutron scattering of Portland cements prepared with a various water-to-cement ratios, gave us information about the microstructure changes in the material. Fractals were a suitable way for structure modelling. Some comments regarding the opportunity of using the most common models are pointed out. (authors)

EnviroAtlas - Portland, ME - BenMAP Results by Block Group

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 146 block groups in Portland, Maine. The US EPA's...

EnviroAtlas - Portland, OR - BenMAP Results by Block Group

Data.gov (United States)

U.S. Environmental Protection Agency — This EnviroAtlas dataset demonstrates the effect of changes in pollution concentration on local populations in 1176 block groups in Portland, Oregon. The US EPA's...

An Approach for Evaluating the Technical Quality of Interim Assessments

Science.gov (United States)

Li, Ying; Marion, Scott; Perie, Marianne; Gong, Brian

2010-01-01

Increasing numbers of schools and districts have expressed interest in interim assessment systems to prepare for summative assessments and to improve teaching and learning. However, with so many commercial interim assessments available, schools and districts are struggling to determine which interim assessment is most appropriate to their needs.…

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

International Nuclear Information System (INIS)

1978-01-01

This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited

In-situ storage: An approach to interim remedial action - recent case studies in Canada

International Nuclear Information System (INIS)

Zelmer, R.L.

1991-01-01

The Low-Level Radioactive Waste Management Office (LLRWMO) acts on behalf of the federal government to manage historic low-level radioactive wastes. Recent interim remedial work in the Town of Port Hope, Ontario has included the consolidation of radium and uranium contaminated soils into temporary storage facilities on two sites to await final disposal elsewhere. Simple containments constructed and sited on already contaminated sites have been found effective as part of an interim remedial strategy. The approach has been accepted and supported by the local public. Lessons have been learned from a project management, environmental remediation and engineering design point of view

Pre-conceptual study on the review framework for the radiation shielding safety of the PWR spent fuel cask interim storage in Korea

International Nuclear Information System (INIS)

Kim, Byeong-Soo; Jeong, Jae-Hak; Jeong, Chan-Woo

2006-01-01

In Korea, 20 nuclear power plants are in operation and lots of spent fuels are on the onsite storage. The onsite storage capacity in Korea is supposed to be full around at the year of 2016 and interim storage facilities could be considered to be constructed before 2016. A review framework to evaluate the radiation shielding safety of the interim storage facilities is developed in this study. It includes acceptance criteria, review procedures and activities of independent analyses. A case study is performed to apply the review framework. Modeling the review reference storage, evaluating the source terms and calculating the photon fluxes are performed. It is shown that the application of the review framework could satisfy the regulatory demand that would arise in the near future in the review area of the radiation shielding safety of the interim storage in Korea. (author)

Portland cement hydration and early setting of cement stone intended for efficient paving materials

Science.gov (United States)

Grishina, A.

2017-10-01

Due to the growth of load on automotive roads, modern transportation engineering is in need of efficient paving materials. Runways and most advanced highways require Portland cement concretes. This makes important the studies directed to improvement of binders for such concretes. In the present work some peculiarities of the process of Portland cement hydration and early setting of cement stone with barium hydrosilicate sol were examined. It was found that the admixture of said sol leads to a shift in the induction period to later times without significant change in its duration. The admixture of a modifier with nanoscale barium hydrosilicates increases the degree of hydration of the cement clinker minerals and changes the phase composition of the hydration products; in particular, the content of portlandite and tricalcium silicate decreases, while the amount of ettringite increases. Changes in the hydration processes of Portland cement and early setting of cement stone that are caused by the nanoscale barium hydrosilicates, allow to forecast positive technological effects both at the stage of manufacturing and at the stage of operation. In particular, the formwork age can be reduced, turnover of molds can be increased, formation of secondary ettringite and corrosion of the first type can be eliminated.

76 FR 12370 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

Science.gov (United States)

2011-03-07

... Production Act of 1993--Portland Cement Association Notice is hereby given that, on February 02, 2011... seq. (``the Act''), Portland Cement Association (``PCA'') has filed written notifications..., Praxair, Danbury, CT; Metso Minerals, York, PA; Lehigh Cement Company LLC, Allentown, PA; Lehigh Northwest...

76 FR 34252 - Notice Pursuant to the National Cooperative Research and Production Act of 1993; Portland Cement...

Science.gov (United States)

2011-06-13

... Production Act of 1993; Portland Cement Association Notice is hereby given that, on May 12, 2011, pursuant to.... (``the Act''), Portland Cement Association (``PCA'') has filed written notifications simultaneously with... plaintiffs to actual damages under specified circumstances. Specifically, Drake Cement, LLC, Scottsdale, AZ...

Global Spent Fuel Logistics Systems Study (GSFLS). Volume 2A. GSFLS visit findings (appendix). Interim report

Energy Technology Data Exchange (ETDEWEB)

None

1978-01-31

This appendix is a part of the interim report documentation for the Global Spent Fuel Logistics System (GSFLS) study. This appendix provides the legal/regulatory reference material, supportive of Volume 2 - GSFLS Visit Finding and Evaluations; and certain background material on British Nuclear Fuel Limited (BNFL).

Thermal analysis of borogypsum and its effects on the physical properties of Portland cement

International Nuclear Information System (INIS)

Elbeyli, Iffet Yakar; Derun, Emek Moeroeydor; Guelen, Jale; Piskin, Sabriye

2003-01-01

Borogypsum, which consists mainly of gypsum crystals, B 2 O 3 and some impurities, is formed during the production of boric acid from colemanite, which is an important borate ore. In this study, the effect of borogypsum and calcined borogypsum on the physical properties of ordinary Portland cement (OPC) has been investigated. The calcination temperature and transformations in the structures of borogypsum and natural gypsum were determined by differential thermal analysis (DTA), thermogravimetric analysis (TGA) and X-ray diffraction (XRD) techniques. Thermal experiments were carried out between ambient temperature and 500 deg. C in an air atmosphere at a heating rate of 10 deg. C min -1 . After calculation of enthalpy and determination of conversion temperatures, borogypsum (5% and 7%), hemihydrate borogypsum (5%) and natural gypsum (5%) were added separately to Portland cement clinker and cements were ground in the laboratory. The final products were tested for chemical analysis, compressive strength, setting time, Le Chatelier expansion and fineness properties according to the European Standard (EN 196). The results show that increasing the borogypsum level in Portland cement from 5% to 7% caused an increase in setting time and a decrease in soundness expansion and compressive strength. The cement prepared with borogypsum (5%) was found to have similar strength properties to those obtained with natural gypsum, whereas a mixture containing 5% of hemihydrate borogypsum was found to develop 25% higher compressive strength than the OPC control mixtures at 28 days. For this reason, utilization of calcined borogypsum in cement applications is expected to give better results than untreated borogypsum. It is concluded that hemihydrate borogypsum could be used as a retarder for Portland cement as an industrial side. This would play an important role in reducing environmental pollution

Structure investigations on Portland cement paste by small angle neutron scattering

International Nuclear Information System (INIS)

Dragolici, C. A.; Len, A.

2003-01-01

Portland cement pastes consist of many crystalline and non-crystalline phases in various ranges of sizes (nm and mm scale). The crystalline phases are embedded in amorphous phases of the hydration products. We investigated the structural changes of hydrating phases in the time interval of 1-30 days at Budapest Neutron Center's SANS diffractometer. The small angle neutron scattering of Portland cements prepared with a water-to-cement ratio from 0,3 to 0,8 gave us information about the microstructure changes in the material. Fractals were a suitable way for structure modelling. The variation of fractals size depending on the preparation-to-measurement time interval and water-to-cement ratio could be observed. (authors)

Development of Mix Design Method in Efforts to Increase Concrete Performance Using Portland Pozzolana Cement (PPC)

Science.gov (United States)

Krisnamurti; Soehardjono, A.; Zacoeb, A.; Wibowo, A.

2018-01-01

Earthquake disaster can cause infrastructure damage. Prevention of human casualties from disasters should do. Prevention efforts can do through improving the mechanical performance of building materials. To achieve high-performance concrete (HPC), usually used Ordinary Portland Cement (OPC). However, the most widely circulating cement types today are Portland Pozzolana Cement (PPC) or Portland Composite Cement (PCC). Therefore, the proportion of materials used in the HPC mix design needs to adjust to achieve the expected performance. This study aims to develop a concrete mix design method using PPC to fulfil the criteria of HPC. The study refers to the code/regulation of concrete mixtures that use OPC based on the results of laboratory testing. This research uses PPC material, gravel from Malang area, Lumajang sand, water, silica fume and superplasticizer of a polycarboxylate copolymer. The analyzed information includes the investigation results of aggregate properties, concrete mixed composition, water-binder ratio variation, specimen dimension, compressive strength and elasticity modulus of the specimen. The test results show that the concrete compressive strength achieves value between 25 MPa to 55 MPa. The mix design method that has developed can simplify the process of concrete mix design using PPC to achieve the certain desired performance of concrete.

Effect of addition of Sikament-R superplasticizer on the hydration characteristics of portland cement pastes

Directory of Open Access Journals (Sweden)

Safaa.M. El Gamal

2012-08-01

Full Text Available The effect of addition of Sikament-R superplasticizer (modified lignosulphonate base on the hydration characteristics of hardened Portland cement pastes were studied at different curing conditions. Four mixtures were prepared using 0, 0.2, 0.4 and 0.6 wt% addition of Sikament-R superplasticizer (SR of cement. These pastes were hydrated under two different conditions; (i normal curing at room temperature; 25 °C up to 90 days periods and (ii hydrothermal curing at a pressure of 8 atm. of saturated steam up to 24 h. The compressive strength, combined water content, free lime content, gel/space ratio and microstructure of hardened cement pastes were studied. The results revealed that addition of SR superplasticizer promote the dispersion of cement particles and interacts with Ca(OH2. The addition of SR superplasticizer exhibits Portland cement better workability during the preparation of pastes. In addition, amore compact structure were obtained leading to higher values of compressive strength for all the hardened hydrated pastes under both normal and hydrothermal curing. The results indicated that the addition of SR superplasticizer to Portland cement does not alter the types of hydration products formed during normal or hydrothermal conditions; only it caused a decrease in the degree of the porosity of the formed pastes.

Possibility of using waste tire rubber and fly ash with Portland cement as construction materials.

Science.gov (United States)

Yilmaz, Arin; Degirmenci, Nurhayat

2009-05-01

The growing amount of waste rubber produced from used tires has resulted in an environmental problem. Recycling waste tires has been widely studied for the last 20 years in applications such as asphalt pavement, waterproofing systems and membrane liners. The aim of this study is to evaluate the feasibility of utilizing fly ash and rubber waste with Portland cement as a composite material for masonry applications. Class C fly ash and waste automobile tires in three different sizes were used with Portland cement. Compressive and flexural strength, dry unit weight and water absorption tests were performed on the composite specimens containing waste tire rubber. The compressive strength decreased by increasing the rubber content while increased by increasing the fly ash content for all curing periods. This trend is slightly influenced by particle size. For flexural strength, the specimens with waste tire rubber showed higher values than the control mix probably due to the effect of rubber fibers. The dry unit weight of all specimens decreased with increasing rubber content, which can be explained by the low specific gravity of rubber particles. Water absorption decreased slightly with the increase in rubber particles size. These composite materials containing 10% Portland cement, 70% and 60% fly ash and 20% and 30% tire rubber particles have sufficient strength for masonry applications.

75 FR 4423 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

Science.gov (United States)

2010-01-27

... Production Act of 1993--Portland Cement Association Notice is hereby given that, on December 14, 2009... seq. (``the Act''), Portland Cement Association (``PCA'') has filed written notifications... Cement, Hannibal, MO has been added as a party to this venture. Also, the following parties have...

Engineering study: disposition of terminal liquors for interim storage. [Eight alternative processes

Energy Technology Data Exchange (ETDEWEB)

Metz, W.P.; Ogren, W.E.

1975-02-01

Eight alternative processes were chosen as being technologically feasible within the time frame dictated by budgeting procedures and terminal liquor availability. Solidified waste products acceptable for single-shell tank storage were assumed to be placed in available single-shell tanks. Double-shell tanks were used only for the more mobile terminal liquors or semi-solid mush products. The mush, chemical neutralization, and clay in-tank processes offer potential savings of tens of millions of dollars over double-shell tank storage of terminal liquors. In order to achieve this cost savings, the process development and demonstration must be completed prior to the beginning of double-shell tank construction (Dec. 1976) expected to be funded from a fiscal year 1977 line item. Budgeting for these additional double-shell tanks must proceed since the processing options discussed here are not yet available and may not prove to be available at the required time. This study indicates the following topics for additional study: Process technology development to achieve interim storage of terminal liquor products receives the greatest emphasis as a means of reducing capital expenditures. Interim storage product criteria, waste inventory, and conversion to final form require definition to allow comparison of the alternatives for disposition of terminal liquors. The pseudotechnical nature of product acceptability criteria is important to the evaluation of the partial neutralization and aluminum removal alternatives. More accurate estimates of terminal liquor quantity and composition are required to give a sound technical basis for choosing the appropriate processing alternative. Retrieval and reprocessing operations may affect the comparisons presented by this study. (DLC)

Nanotechnology-Based Performance Improvements For Portland Cement Concrete - Phase I

Science.gov (United States)

2012-08-16

A fundamental understanding of the nano-structure of Portland cement concrete (PCC) is the key to realizing significant breakthroughs regarding high performance and susta : (MBTC 2095/3004) using molecular dynamics (MD) provided new understanding of ...

Subsurface Interim Measures/Interim Remedial Action Plan/ Environmental Assessment and Decision Document, Operable Unit No. 2

International Nuclear Information System (INIS)

1992-01-01

The subject Interim Measures/Interim Remedial Action plan/Environmental Assessment (IM/IRAP/EA) addresses residual free-phase volatile organic compound (VOC) contamination suspected in the subsurface within an area identified as Operable Unit No. 2 (OU2). This IM/IRAP/EA also addresses radionuclide contamination beneath the 903 Pad at OU2. Although subsurface VOC and radionuclide contamination on represent a source of OU2 ground-water contamination, they pose no immediate threat to public health or the environment. This volume contains five appendices

A Histologic Evaluation on Tissue Reaction to Three Implanted Materials (MTA, Root MTA and Portland Cement Type I in the Mandible of Cats

Directory of Open Access Journals (Sweden)

F. Sasani

2004-09-01

Full Text Available Statement of Problem: Nowadays Mineral Trioxide aggregate (MTA is widely used for root end fillings, pulp capping, perforation repair and other endodontic treatments.Investigations have shown similar physical and chemical properties for Portland cement and Root MTA with those described for MTA.Purpose: The aim of this in vitro study was to evaluate the tissue reaction to implanted MTA, Portland cement and Root MTA in the mandible of cats.Materials and Methods: Under asepsis condition and general anesthesia, a mucoperiosteal flap, following the application of local anesthesia, was elevated to expose mandibular symphysis. Two small holes in both sides of mandible were drilled. MTA, Portland cement and Root MTA were mixed according to the manufacturers, recommendation and placed in bony cavities. In positive control group, the test material was Zinc oxide powder plus tricresoformalin. In negative control group, the bony cavities were left untreated. After 3,6 and 12 weeks, the animals were sacrificed and the mandibular sections were prepared for histologic examination under light microscope. The presence and thickness of inflammation, presence of fibrosis capsule, the severity of fibrosis and bone formation were investigated. The data were submitted to Exact Fisher test, chi square test and Kruskal-Wallis test for statistical analysis.Results: No statistically significant differences were found in the degree of inflammation,presence of fibrotic capsule, severity of fibrosis and inflammation thickness between Root MTA, Portland cement and MTA (P>0.05. There was no statistical difference in boneformation between MTA and Portland cement (P>0.05. However, bone formation was not found in any of the Root MTA specimens and the observed tissue was exclusively of fibrosis type.Conclusion: The physical and histological results observed with MTA are similar to those of Root MTA and Portland cement. Additionally, all of these three materials are biocompatible

CMM Interim Check Design of Experiments (U)

Energy Technology Data Exchange (ETDEWEB)

Montano, Joshua Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-07-29

Coordinate Measuring Machines (CMM) are widely used in industry, throughout the Nuclear Weapons Complex and at Los Alamos National Laboratory (LANL) to verify part conformance to design definition. Calibration cycles for CMMs at LANL are predominantly one year in length and include a weekly interim check to reduce risk. The CMM interim check makes use of Renishaw’s Machine Checking Gauge which is an off-the-shelf product simulates a large sphere within a CMM’s measurement volume and allows for error estimation. As verification on the interim check process a design of experiments investigation was proposed to test a couple of key factors (location and inspector). The results from the two-factor factorial experiment proved that location influenced results more than the inspector or interaction.

77 FR 5573 - Notice Pursuant to the National Cooperative Research and Production Act of 1993-Portland Cement...

Science.gov (United States)

2012-02-03

... Production Act of 1993--Portland Cement Association Notice is hereby given that, on January 6, 2012, pursuant... seq. (``the Act''), Portland Cement Association (``PCA'') has filed written notifications..., Newark, DE, has been added as a party to this venture. Also, Texas-Lehigh Cement Company, Buda, TX...

Permitting plan for the high-level waste interim storage

International Nuclear Information System (INIS)

Deffenbaugh, M.L.

1997-01-01

This document addresses the environmental permitting requirements for the transportation and interim storage of solidified high-level waste (HLW) produced during Phase 1 of the Hanford Site privatization effort. Solidified HLW consists of canisters containing vitrified HLW (glass) and containers that hold cesium separated during low-level waste pretreatment. The glass canisters and cesium containers will be transported to the Canister Storage Building (CSB) in a U.S. Department of Energy (DOE)-provided transportation cask via diesel-powered tractor trailer. Tri-Party Agreement (TPA) Milestone M-90 establishes a new major milestone, and associated interim milestones and target dates, governing acquisition and/or modification of facilities necessary for: (1) interim storage of Tank Waste Remediation Systems (TWRS) immobilized HLW (IHLW) and other canistered high-level waste forms; and (2) interim storage and disposal of TWRS immobilized low-activity tank waste (ILAW). An environmental requirements checklist and narrative was developed to identify the permitting path forward for the HLW interim storage (HLWIS) project (See Appendix B). This permitting plan will follow the permitting logic developed in that checklist

Toxicity and Histopathological Effects of Portland Cement Powder in ...

African Journals Online (AJOL)

Hepatic lesions in the liver tissues of fish exposed to Portland cement powder in solution were characterized by degeneration of hepatocyte, vascuolization of cell cytoplasm, fatty degeneration and hypertrophy of hepatocytes. Histological comparison of tissues indicated that most damage occurred in the gill rather than in ...

Utilization of steel slag for Portland cement clinker production.

Science.gov (United States)

Tsakiridis, P E; Papadimitriou, G D; Tsivilis, S; Koroneos, C

2008-04-01

The aim of the present research work is to investigate the possibility of adding steel slag, a by-product of the conversion of iron to steel process, in the raw meal for the production of Portland cement clinker. Two samples of raw meals were prepared, one with ordinary raw materials, as a reference sample ((PC)(Ref)), and another with 10.5% steel slag ((PC)(S/S)). Both raw meals were sintered at 1450 degrees C. The results of chemical and mineralogical analyses as well as the microscopic examination showed that the use of the steel slag did not affect the mineralogical characteristics of the so produced Portland cement clinker. Furthermore, both clinkers were tested by determining the grindability, setting times, compressive strengths and soundness. The hydration products were examined by XRD analysis at 2, 7, 28 and 90 days. The results of the physico-mechanical tests showed that the addition of the steel slag did not negatively affect the quality of the produced cement.

Influence Of Cement Kiln Dust As Partial Replacement On Some Properties Of Ordinary And White Portland Cement

Directory of Open Access Journals (Sweden)

Salah Sharif

2013-04-01

Full Text Available Cement Kiln Dust (CKD is produced as a solid waste with large quantities during manufacturing of Portland cement clinker. The possibility of utilizing CKD as partial replacement for Ordinary Portland Cement (OPC and White Portland Cement (WPC produced in factories of the Iraqi cement state company has been examined in this study to fulfil the environmental and economical aims. Different percentages of CKD were blended with OPC and WPC mixes. The results show that the amount of water for normal consistency were increased with about 39 % and 31 % for OPC and WPC blended with 25 % CKD. The setting time (initial and final decreases with increasing percent of CKD added. Compressive strength decreases slightly with increasing CKD content up to 10 %. For 7- day curing time, it decreases 7 % and 9 % for OPC and WPC mixes, respectively. As percent of added CKD increases to more than 10 %, the compressive strength and other parameters where affected significantly. Overall results proved that OPC and WPC blended with up to 10 % CKD are admissible for passing relevant specification requirements.

Physicochemical and mechanical properties of zirconium oxide and niobium oxide modified Portland cement-based experimental endodontic sealers.

Science.gov (United States)

Viapiana, R; Flumignan, D L; Guerreiro-Tanomaru, J M; Camilleri, J; Tanomaru-Filho, M

2014-05-01

To evaluate the physicochemical and mechanical properties of Portland cement-based experimental sealers (ES) with different radiopacifying agents (zirconium oxide and niobium oxide micro- and nanoparticles) in comparison with the following conventional sealers: AH Plus, MTA Fillapex and Sealapex. The materials were tested for setting time, compressive strength, flow, film thickness, radiopacity, solubility, dimensional stability and formaldehyde release. Data were subjected to anova and Tukey tests (P 0.05) and lower solubility when compared with MTA Fillapex and Sealapex (P Portland cement-based experimental endodontic sealers presented physicochemical properties according to the specifications no 57 ANSI/ADA (ADA Professional Product Review, 2008) and ISO 6876 (Dentistry - Root Canal Sealing Materials, 2012, British Standards Institution, London, UK). The sealers had setting times and flow ability that was adequate for clinical use, satisfactory compressive strength and low solubility. Additional studies should be carried out with the purpose of decreasing the film thickness and to determine the ideal ratio of radiopacifying agents in Portland cement-based root canal sealers. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Network Level Carbon Dioxide Emissions From On-road Sources in the Portland OR, (USA) Metropolitan Area

Science.gov (United States)

Powell, J.; Butenhoff, C. L.; Rice, A. L.

2014-12-01

To mitigate climate change, governments at multiple levels are developing policies to decrease anthropogenic carbon dioxide (CO2) emissions. The City of Portland (Oregon) and Multnomah County have adopted a Climate Action Plan with a stated goal of reducing emissions to 80% below 1990 levels by 2050. The transportation sector alone accounts for about 40% of total emissions in the Portland metropolitan area. Here we show a new street-level model of on-road mobile CO2 emissions for the Portland, OR metropolitan region. The model uses hourly traffic counter recordings made by the Portland Bureau of Transportation at 9,352 sites over 21 years (1986-2006), augmented with freeway loop detector data from the Portland Regional Transportation Archive Listing (PORTAL) transportation data archive. We constructed a land use regression model to fill in traffic network gaps with traffic counts as the dependent variable using GIS data such as road class (32 categories) and population density. The Environmental Protection Agency (EPA) MOtor Vehicle Emission Simulator (MOVES) model was used to estimate transportation CO2 emissions. The street-level emissions can be aggregated and gridded and used as input to atmospheric transport models for comparison with atmospheric measurements. This model also provides an independent assessment of top-down inventories that determine emissions from fuel sales, while being an important component of our ongoing effort to assess the effectiveness of emission mitigation strategies at the urban scale.

12 CFR 541.18 - Interim Federal savings association.

Science.gov (United States)

2010-01-01

... an existing savings and loan holding company or to facilitate any other transaction the Office may... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Interim Federal savings association. 541.18... REGULATIONS AFFECTING FEDERAL SAVINGS ASSOCIATIONS § 541.18 Interim Federal savings association. The term...

Single-shell tank interim stabilization project plan

Energy Technology Data Exchange (ETDEWEB)

Ross, W.E.

1998-03-27

Solid and liquid radioactive waste continues to be stored in 149 single-shell tanks at the Hanford Site. To date, 119 tanks have had most of the pumpable liquid removed by interim stabilization. Thirty tanks remain to be stabilized. One of these tanks (C-106) will be stabilized by retrieval of the tank contents. The remaining 29 tanks will be interim stabilized by saltwell pumping. In the summer of 1997, the US Department of Energy (DOE) placed a moratorium on the startup of additional saltwell pumping systems because of funding constraints and proposed modifications to the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) milestones to the Washington State Department of Ecology (Ecology). In a letter dated February 10, 1998, Final Determination Pursuant to Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) in the Matter of the Disapproval of the DOE`s Change Control Form M-41-97-01 (Fitzsimmons 1998), Ecology disapproved the DOE Change Control Form M-41-97-01. In response, Fluor Daniel Hanford, Inc. (FDH) directed Lockheed Martin Hanford Corporation (LNMC) to initiate development of a project plan in a letter dated February 25, 1998, Direction for Development of an Aggressive Single-Shell Tank (SST) Interim Stabilization Completion Project Plan in Support of Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). In a letter dated March 2, 1998, Request for an Aggressive Single-Shell Tank (SST) Interim Stabilization Completion Project Plan, the DOE reaffirmed the need for an aggressive SST interim stabilization completion project plan to support a finalized Tri-Party Agreement Milestone M-41 recovery plan. This project plan establishes the management framework for conduct of the TWRS Single-Shell Tank Interim Stabilization completion program. Specifically, this plan defines the mission needs and requirements; technical objectives and approach; organizational structure, roles, responsibilities

Single-shell tank interim stabilization project plan

International Nuclear Information System (INIS)

Ross, W.E.

1998-01-01

Solid and liquid radioactive waste continues to be stored in 149 single-shell tanks at the Hanford Site. To date, 119 tanks have had most of the pumpable liquid removed by interim stabilization. Thirty tanks remain to be stabilized. One of these tanks (C-106) will be stabilized by retrieval of the tank contents. The remaining 29 tanks will be interim stabilized by saltwell pumping. In the summer of 1997, the US Department of Energy (DOE) placed a moratorium on the startup of additional saltwell pumping systems because of funding constraints and proposed modifications to the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) milestones to the Washington State Department of Ecology (Ecology). In a letter dated February 10, 1998, Final Determination Pursuant to Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) in the Matter of the Disapproval of the DOE's Change Control Form M-41-97-01 (Fitzsimmons 1998), Ecology disapproved the DOE Change Control Form M-41-97-01. In response, Fluor Daniel Hanford, Inc. (FDH) directed Lockheed Martin Hanford Corporation (LNMC) to initiate development of a project plan in a letter dated February 25, 1998, Direction for Development of an Aggressive Single-Shell Tank (SST) Interim Stabilization Completion Project Plan in Support of Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement). In a letter dated March 2, 1998, Request for an Aggressive Single-Shell Tank (SST) Interim Stabilization Completion Project Plan, the DOE reaffirmed the need for an aggressive SST interim stabilization completion project plan to support a finalized Tri-Party Agreement Milestone M-41 recovery plan. This project plan establishes the management framework for conduct of the TWRS Single-Shell Tank Interim Stabilization completion program. Specifically, this plan defines the mission needs and requirements; technical objectives and approach; organizational structure, roles, responsibilities

76 FR 50252 - Gray Portland Cement and Cement Clinker From Japan; Scheduling of an Expedited Five-Year Review...

Science.gov (United States)

2011-08-12

... INTERNATIONAL TRADE COMMISSION [Investigation No. 731-TA-461 (Third Review)] Gray Portland Cement and Cement Clinker From Japan; Scheduling of an Expedited Five-Year Review Concerning the Antidumping Duty Order on Gray Portland Cement and Cement Clinker From Japan AGENCY: United States International...

40 CFR 80.141 - Interim detergent gasoline program.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Interim detergent gasoline program. 80... (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES Detergent Gasoline § 80.141 Interim detergent gasoline... apply to: (i) All gasoline sold or transferred to a party who sells or transfers gasoline to the...

The Influence of Diatomite on the Strength and Microstructure of Portland Cement

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Liu Jun

2016-01-01

Full Text Available To study the influence of the types and mixing amount of diatomite on the Portland cement, we prepared the cement specimen doped with the calcined first-grade, first-grade and second-grade diatomite ,tested the 3d, 7d, 14d compressive strength, and studied and discussed phase, structure and morphology of diatomite in the binary system by the method of XRD, SEM . Experimental results show that with the addition of diatomite, the strength of cement paste increase; the optimal contents of calcined first-grade ,first-grade and second-grade diatomite in Portland cement are 5%,Compared to the blank group, the strength of specimen can be increased by 54.6%, 15.4% and 10.2%, respectively; At the same time ,the 7d microscopic hydration of different diatomite particles were analyzed through the experiment , and the shell of calcined diatomite particles were better hydrated than that of first-grade and second-grade diatomite particles. The results indicate that the diatomite can improve the strength of cement paste, the hydration of different diatomite particles can influence the growth of cement paste strength.

Ettringite and C-S-H Portland cement phases for waste ion immobilization: A review

International Nuclear Information System (INIS)

Gougar, M.L.D.; Scheetz, B.E.; Roy, D.M.

1996-01-01

The formation, structure and chemistry of the ettringite and C-S-H phases of Portland cement have been reviewed as they relate to waste ion immobilization. The purpose of this review was to investigate the use of Portland cement as a host for priority metallic pollutants as identified by the Environmental Protection Agency and as a host for radioactive waste ions as identified in 40 CFR 191. Ettringite acts as host to a number of these ions in both the columnar and channel sections of the crystal structure. Substitutions have been made at the calcium, aluminum, hydroxide and sulfate sites. C-S-H also hosts a number of the waste species in both ionic and salt form. Immobilization mechanisms for C-S-H include sorption, phase mixing and substitution. The following ions have not apparently been reported as specifically immobilized by one of these phases: Ag, Am, Np, Pu, Ra, Tc, Th and Sn; however, some of these ions are immobilized by Portland cement

Applications of solid-state Nuclear Magnetic Resonance (NMR) in studies of Portland cements-based materials

DEFF Research Database (Denmark)

Skibsted, Jørgen; Andersen, Morten Daugaard; Jakobsen, Hans Jørgen

2007-01-01

Solid-state NMR spectroscopy represents an important research tool in the characterization of a range of structural properties for cement-based materials. Different approaches of the technique can be used to obtain information on hydration kinetics, mobile and bound water, porosity, and local...... atomic structures. After a short introduction to these NMR techniques, it is exemplified how magic-angle spinning (MAS) NMR can provide quantitative and structural information about specific phases in anhydrous and hydrated Portland cements with main emphasis on the incorporation of Al3+ ions...

Fusion Breeder Program interim report

International Nuclear Information System (INIS)

Moir, R.; Lee, J.D.; Neef, W.

1982-01-01

This interim report for the FY82 Fusion Breeder Program covers work performed during the scoping phase of the study, December, 1981-February 1982. The goals for the FY82 study are the identification and development of a reference blanket concept using the fission suppression concept and the definition of a development plan to further the fusion breeder application. The context of the study is the tandem mirror reactor, but emphasis is placed upon blanket engineering. A tokamak driver and blanket concept will be selected and studied in more detail during FY83

Characterization of floodflows along the Arkansas River without regulation by Pueblo Reservoir, Portland to John Martin Reservoir, Southeastern Colorado

Science.gov (United States)

Little, John R.; Bauer, Daniel P.

1981-01-01

The need for a method for estimating flow characteristics of flood hydrographs between Portland, Colo., and John Martin Reservoir has been promoted with the construction of the Pueble Reservoir. To meet this need a procedure was developed for predicting floodflow peaks, traveltimes, and volumes at any point along the Arkansas River between Portland and John Martin Reservoir without considering the existing Pueble Reservoir detention effects. A streamflow-routing model was calibrated initially and then typical flood simulations were made for the 164.8-mile study reach. Simulations were completed for varying magnitudes of floods and antecedent streamflow conditions. Multiple regression techniques were then used with simulation results as input to provide predictive relationships for food peak, volume, and traveltime. Management practices that may be used to benefit water users in the area include providing methods for the distribution and allotment of the flood waters upstream of Portland to different downstream water users according to Colorado water law and also under the Arkansas River Compact. (USGS)

Description of the structural evolution of a hydrating portland cement paste by SANS

International Nuclear Information System (INIS)

Haeussler, F.; Eichhorn, F.; Baumbach, H.

1994-01-01

On the spectrometer MURN at the pulsed reactor IBR-2 dry Portland cement, silica fume, and a hydrating Portland cement paste were studied by small-angle neutron scattering (SANS). By using the TOF-method a momentum transfer from 0.07 nm -1 to 7 nm -1 is detectable. Every component (dry cement powder, clinker minerals, hydrating cement pastes) shows a different scattering behaviour. In the measured Q-region the hardening cement paste does not show a Porod-like behaviour of SANS-curves. In contrast the Porod's potential law holds for dry powder samples of clinker minerals and silica fume. In experiments carried out to observe the hydration progress within the first 321 days the characteristics of the scattering curves (potential behaviour, the radius of gyration, and the macroscopic scattering cross section at Q = 0 nm -1 were measured. Some evolution of the inner structure of the hardened cement paste was noted. (orig.)

Una nota sobre los Hormigones de Cemento Portland (HCP y Hormigones de Cemento Portland con Adiciones (HCPA

Directory of Open Access Journals (Sweden)

Talero Morales, Rafael

1993-09-01

Full Text Available El hombre contemporáneo ha dividido el proceso evolutivo de la humanidad en macroperíodos de tiempo relacionados con avances significativos obtenidos en el campo de los materiales. Así se define la edad de piedra, bronce, hierro, cobre, etc. Y siguiendo esta tendencia, probablemente las generaciones futuras podrán hablar de esta época como la "edad del hormigón" y mostrar los monumentales vestigios que, en su mayor parte, se han construido con hormigón de cemento portland.

Explicit feedback to enhance the effect of an interim assessment: a cross-over study on learning effect and gender difference.

Science.gov (United States)

Olde Bekkink, Marleen; Donders, Rogier; van Muijen, Goos N P; de Waal, Rob M W; Ruiter, Dirk J

2012-11-01

In a previous study we demonstrated by a prospective controlled design that an interim assessment during an ongoing small group work (SGW) session resulted in a higher score in the course examination. As this reflects the so-called testing effect, which is supposed to be enhanced by feedback, we investigated whether feedback following an interim assessment would have an effect on the score of the course exam, and whether the effect is influenced by the gender of the student. During a General Pathology bachelor course all 386 (bio) medical students took an interim assessment on the topics cell damage (first week) and tumour pathology (fourth week). The intervention consisted of immediate detailed oral feedback on the content of the questions of the interim assessment by the tutor, including the rationale of the correct and incorrect answers. It concerned a prospective randomized study using a cross-over design. Outcome measures were: (1) the difference in the normalized scores (1-10) of the course examination multiple choice questions related to the two topics, (2) effect of gender, and (3) gender-specific scores on formal examination. The effect of feedback was estimated as half the difference in the outcome between the two conditions. Mixed-model analysis was used whereby the SGW group was taken as the study target. The scores of the questions on cell damage amounted to 7.70 (SD 1.59) in the group without and 7.78 (SD 1.39) in the group with feedback, and 6.73 (SD 1.51) and 6.77 (SD 1.60), respectively, for those on tumour pathology. No statistically significant effect of feedback was found: 0.02 on a scale of 1-10 (95 % CI: -0.20; 0.25). There were no significant interactions of feedback with gender. Female students scored 0.43 points higher on the formal examination in comparison with their male colleagues. No additional effect of immediate explicit feedback following an interim assessment during an SGW session in an ongoing bachelor course could be

Properties of Portland-Composite Cements with metakaolin: Commercial and manufactured by Thermal Activation of Serbian Kaolin Clay

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Mitrovic A.

2012-09-01

Full Text Available Portland-composite cements (CEM II were prepared with addition of 5 to 35% of metakaolin (MK, manufactured by thermal activation/calcination of Serbian kaolin clay, and commercial matakaolin (CMK. Performance of the composite cements was evaluated, through the setting time (initial and final, compressive strengths (for ages 2, 7, 28, 90 and 180 days and soundness, and compared with control cement (Portland cement – CEM I. Setting time (initial and final is accelerated in Portlandcomposite cements, for both metakaolins used. The acceleration is higher in cement with addition of commercial metakaolin. Lower compressive strength is obtained after 2 days of curing for all Portland-composite cements in comparison with control cement, since pozzolanic reaction still did not show its effect. After 7 days, pozzolanic reaction show its effect, manifested as compressive strength increase of Portland-composite cements with addition of up to 35% of CMK, and 25% in the case of cements with MK. After 28 days compressive strength was higher than that for control cement for cements prepared with addition of CMK, and with addition of up to 25% MK. After 90 days increased compressive strength was noticed with addition of 10 - 20% of CMK, and with 10 and 15% of MK, while after 180 days addition of both metakaolins influences compressive strength decrease. The results of the soundness, 0.5 mm for CEM I, and 1.0 mm in most Portland-composite cements indicate soundness increase with addition of metakaolins. Generally, better performance of Portland-composite cements was obtained with addition of commercial metakaolin, which may be attributed to the differences in the pozzolanic activity of the applied metakaolins, 20.5 MPa and 14.9 MPa for CMK and MK, respectively. By our previous findings pozzolanic activity of the thermally activated clay may be increased by subsequent milling of the metakaolin manufactured by thermal activation process.

The influence of the amount addition and kind of the active silica fume in the mechanical properties of the cement Portland concrete

International Nuclear Information System (INIS)

Silva, I.J. da; Melo, A.B. de; Liborio, J.B.L.; Souza, M.F. de

1998-01-01

This study presents an evaluation of the influence of the amount addition and of active silica type deriving from residues of the production of Iron-Silicon alloys of brasilian industries, on the mechanical properties of the concrete made with basaltic aggregates with D max ≥9,5 mm using Portland cements CP II E 32. The study has for objective to evaluate the efficiency of the active silica on the mechanical resistance of the high performance concrete (CAD), when used in substitution of the Portland cement, even so maintaining the same amount of agglomerant material. They are appraised amount of 5%, 8%, 10%, 12% and 15% of active silica in relation to Portland cement mass. The results suggest that for the appraised silicas there is little efficiency. Other aspects related to the mixtures just with addictive water reducers are commented with the purpose of also providing a high performance concrete. (author)

Influence of moisture condition on chloride diffusion in partially saturated ordinary Portland cement mortar

NARCIS (Netherlands)

Zhang, Y.; Zhang, M.; Ye, G.

2018-01-01

Experiments have been carried out to study the influence of moisture condition, including moisture content and its distribution, on the chloride diffusion in partially saturated ordinary Portland cement mortar. The mortar samples with water-to-cement (w/c) ratios of 0.4, 0.5 and 0.6, cured for 1

Effect of radiopaque Portland cement on mineralization in human dental pulp cells.

Science.gov (United States)

Min, Kyung-San; Lee, Sang-Im; Lee, Yoon; Kim, Eun-Cheol

2009-10-01

The aim of this study was to investigate whether radiopaque Portland cement (RPC) facilitates the mineralization process in human dental pulp cells (HDPCs) compared with pure Portland cement (PC). Under a scanning electron microscope (SEM), cellular morphology was evaluated. Alkaline phosphatase (ALP) activity was analyzed, and nodule formation was assessed by performing Alizarin Red S staining. In addition, the mRNA expressions of mineralization-related proteins were evaluated by performing a real-time polymerase chain reaction. On SEM evaluation, healthy HDPCs were found adhering to the surfaces of PC and RPC. The ALP activity increased in the PC and RPC groups compared with the control group at 1 day. Alizarin Red stain increased in the PC and RPC groups compared with the control group at 2 and 3 weeks. The mRNA expression of dentin sialophosphoprotein increased at 14 days in the PC and RPC groups. These results show that PC and RPC have similar effects in terms of mineralization and suggest that RPC also has the potential to be used as a clinically suitable pulp-capping material.

Design review report FFTF interim storage cask

International Nuclear Information System (INIS)

Scott, P.L.

1995-01-01

Final Design Review Report for the FFTF Interim Storage Cask. The Interim Storage Cask (ISC) will be used for long term above ground dry storage of FFTF irradiated fuel in Core Component Containers (CCC)s. The CCC has been designed and will house assemblies that have been sodium washed in the IEM Cell. The Solid Waste Cask (SWC) will transfer a full CCC from the IEM Cell to the RSB Cask Loading Station where the ISC will be located to receive it. Once the loaded ISC has been sealed at the RSB Cask Loading Station, it will be transferred by facility crane to the DSWC Transporter. After the ISC has been transferred to the Interim Storage Area (ISA), which is yet to be designed, a mobile crane will be used to place the ISC in its final storage location

Choosing a spent fuel interim storage system

International Nuclear Information System (INIS)

Roland, V.; Hunter, I.

2001-01-01

The Transnucleaire Group has developed different modular solutions to address spent fuel interim storage needs of NPP. These solutions, that are present in Europe, USA and Asia are metal casks (dual purpose or storage only) of the TN 24 family and the NUHOMS canister based system. It is not always simple for an operator to sort out relevant choice criteria. After explaining the basic designs involved on the examples of the TN 120 WWER dual purpose cask and the NUHOMS 56 WWER for WWER 440 spent fuel, we shall discuss the criteria that govern the choice of a given spent fuel interim storage system from the stand point of the operator. In conclusion, choosing and implementing an interim storage system is a complex process, whose implications can be far reaching for the long-term success of a spent fuel management policy. (author)

78 FR 67442 - Congestion Mitigation and Air Quality Improvement Program Interim Guidance

Science.gov (United States)

2013-11-12

...] Congestion Mitigation and Air Quality Improvement Program Interim Guidance AGENCY: Federal Highway... Comment. SUMMARY: The FHWA is issuing Interim Guidance on the Congestion Mitigation and Air Quality.../environment/air_quality/cmaq/policy_and_guidance/2008_guidance/ guidance/. DATES: This Interim Guidance is...

Moessbauer and calorimetric studies of portland cement hydration in the presence of black gram pulse

International Nuclear Information System (INIS)

Rai, Sarita; Kurian, Sajith; Dwivedi, V. N.; Das, S. S.; Singh, N. B.; Gajbhiye, N. S.

2009-01-01

Effect of different concentrations of naturally occurring admixture in the form of fine powder of black gram pulse (BGP) on the hydration of Portland cement was studied by isothermal calorimetry and 57 Fe Moessbauer spectroscopy. The spectra were recorded for anhydrous cement and the hydration products at room temperature and 77 K. In the presence of BGP, the spectra showed superparamagnetic doublets at room temperature and the sextet at 77 K, due to the presence of fine particles of iron containing component. Moessbauer studies of hydration products confirmed the formation of nanosize hydration products containing Fe 3+ . The isomer shift (δ) and the quadrupole splitting (ΔE Q ) values of C 4 AF in the cement confirmed iron in an octahedral and tetrahedral environment with +3 oxidation state. The high value of quadrupole splitting showed the high asymmetry of the electron environment around the iron atom. The overall mechanism of the hydration of cement in presence of BGP is discussed.

47 CFR 51.715 - Interim transport and termination pricing.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 3 2010-10-01 2010-10-01 false Interim transport and termination pricing. 51.715 Section 51.715 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) COMMON CARRIER... Telecommunications Traffic § 51.715 Interim transport and termination pricing. (a) Upon request from a...

The biomineralization ability of mineral trioxide aggregate and Portland cement on dentin enhances the push-out strength.

Science.gov (United States)

Reyes-Carmona, Jessie F; Felippe, Mara S; Felippe, Wilson T

2010-02-01

Recently, it was shown that the interaction of each of mineral trioxide aggregate (MTA) and Portland cement with dentin in phosphate-buffered saline (PBS) promotes a biomineralization process that leads to the formation of an interfacial layer with tag-like structures at the cement-dentin interface. This study analyzes the influence of the biomineralization process on the push-out strength of ProRoot MTA (Dentsply Tulsa Dental, Tulsa, OK), MTA Branco (Angelus Soluções Odontológicas, Londrina, PR, Brazil), MTA BIO (Angelus Soluções Odontológicas), or Portland cement with and without calcium chloride. Dentin discs with standardized cavities were filled with ProRoot MTA, MTA Branco, MTA BIO, white Portland cement + 20% bismuth oxide (PC1), or PC1 + 10% of calcium chloride (PC2). The specimens were randomly divided into two groups: cement in contact with a wet cotton pellet for 72 hours or immersed in PBS for 2 months. The bond strengths were measured with the Instron Testing machine (Model 4444; Instron Corp, Canton, MA), and the fractured surfaces on the root walls were observed by scanning electron microscopy. All samples immersed in PBS displayed a significantly greater resistance to displacement than that observed for the samples in contact with a wet cotton pellet for 72 hours (p Portland cements. It was concluded that the biomineralization process positively influenced the push-out bond strength of the cements, particularly the MTA groups. Copyright 2010 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Middle Level Teachers' Perceptions of Interim Reading Assessments: An Exploratory Study of Data-Based Decision Making

Science.gov (United States)

Reed, Deborah K.

2015-01-01

This study explored the data-based decision making of 12 teachers in grades 6-8 who were asked about their perceptions and use of three required interim measures of reading performance: oral reading fluency (ORF), retell, and a benchmark comprised of released state test items. Focus group participants reported they did not believe the benchmark or…

ITER Conceptual design: Interim report

International Nuclear Information System (INIS)

1990-01-01

This interim report describes the results of the International Thermonuclear Experimental Reactor (ITER) Conceptual Design Activities after the first year of design following the selection of the ITER concept in the autumn of 1988. Using the concept definition as the basis for conceptual design, the Design Phase has been underway since October 1988, and will be completed at the end of 1990, at which time a final report will be issued. This interim report includes an executive summary of ITER activities, a description of the ITER device and facility, an operation and research program summary, and a description of the physics and engineering design bases. Included are preliminary cost estimates and schedule for completion of the project

Hydration kinetics modeling of Portland cement considering the effects of curing temperature and applied pressure

International Nuclear Information System (INIS)

Lin Feng; Meyer, Christian

2009-01-01

A hydration kinetics model for Portland cement is formulated based on thermodynamics of multiphase porous media. The mechanism of cement hydration is discussed based on literature review. The model is then developed considering the effects of chemical composition and fineness of cement, water-cement ratio, curing temperature and applied pressure. The ultimate degree of hydration of Portland cement is also analyzed and a corresponding formula is established. The model is calibrated against the experimental data for eight different Portland cements. Simple relations between the model parameters and cement composition are obtained and used to predict hydration kinetics. The model is used to reproduce experimental results on hydration kinetics, adiabatic temperature rise, and chemical shrinkage of different cement pastes. The comparisons between the model reproductions and the different experimental results demonstrate the applicability of the proposed model, especially for cement hydration at elevated temperature and high pressure.

Ecological indices of manufacture of Portland cement clinker and production of the dolomite clinker

Directory of Open Access Journals (Sweden)

Vinnichenko Varvara

2017-01-01

Full Text Available It is shown that the production of dolomite clinker in comparison with that of Portland cement is environmentally appropriate. When calcining dolomite for cementitious binder, the pollution of the atmosphere by carbon dioxide is reduced due to its isolation during decarbonization reactions of calcium carbonates. Reducing fuel consumption for clinker burning provides less carbon dioxide emissions from combustion products. Reducing the firing temperature creates obstacles to the formation of nitrogen oxides. The production of binders from dolomite in comparison with the production of Portland cement helps to protect the environment from contamination

Portland Public Schools Project Chrysalis: Year 2 Evaluation Report.

Science.gov (United States)

Mitchell, Stephanie J.; Gabriel, Roy M.; Hahn, Karen J.; Laws, Katherine E.

In 1994, the Chrysalis Project in Portland Public Schools received funding to prevent or delay the onset of substance abuse among a special target population: high-risk, female adolescents with a history of childhood abuse. Findings from the evaluation of the project's second year of providing assistance to these students are reported here. During…

In vitro evaluation of the marginal integrity of CAD/CAM interim crowns.

Science.gov (United States)

Kelvin Khng, Kwang Yong; Ettinger, Ronald L; Armstrong, Steven R; Lindquist, Terry; Gratton, David G; Qian, Fang

2016-05-01

The accuracy of interim crowns made with computer-aided design and computer-aided manufacturing (CAD/CAM) systems has not been well investigated. The purpose of this in vitro study was to evaluate the marginal integrity of interim crowns made by CAD/CAM compared with that of conventional polymethylmethacrylate (PMMA) crowns. A dentoform mandibular left second premolar was prepared for a ceramic crown and scanned for the fabrication of 60 stereolithical resin dies, half of which were scanned to fabricate 15 Telio CAD-CEREC and 15 Paradigm MZ100-E4D-E4D crowns. Fifteen Caulk and 15 Jet interim crowns were made on the remaining resin dies. All crowns were cemented with Tempgrip under a 17.8-N load, thermocycled for 1000 cycles, placed in 0.5% acid fuschin for 24 hours, and embedded in epoxy resin before sectioning from the mid-buccal to mid-lingual surface. The marginal discrepancy was measured using a traveling microscope, and dye penetration was measured as a percentage of the overall length under the crown. The mean vertical marginal discrepancy of the conventionally made interim crowns was greater than for the CAD/CAM crowns (P=.006), while no difference was found for the horizontal component (P=.276). The mean vertical marginal discrepancy at the facial surface of the Caulk crowns was significantly greater than that of the other 3 types of interim crowns (Pmargin, the mean horizontal component of the Telio crowns was significantly larger than that of the other 3 types, with no difference at the lingual margins (P=.150). The mean percentage dye penetration for the Paradigm MZ100-E4D crowns was significantly greater and for Jet crowns significantly smaller than for the other 3 crowns (Pmarginal discrepancies of the Jet interim crowns at the facial surface and with the horizontal marginal discrepancies of the Caulk interim crowns at the lingual surface (Pmarginal discrepancy was found with the interim crowns fabricated by CAD/CAM as compared with PMMA crowns

Long-term interim storage concepts with conditioning strategies ensuring compatibility with subsequent disposal or reprocessing

International Nuclear Information System (INIS)

Moitrier, C.; Tirel, I.; Villard, C.

2000-01-01

The objective of the CEA studies carried out under research topic 3 (long-term interim storage) of the 1991 French radioactive waste management law is to demonstrate the industrial feasibility of a comprehensive, flexible interim storage facility by thoroughly evaluating and comparing all the basic components of various interim storage concepts. In this context, the CEA is considering reference solutions or concepts based on three primary components (the package, the interim storage facility and the site) suitable for determining the specifications of a very long-term solution. Some aspects are examined in greater detail, such as the implementation of long-term technologies, conditioning processes ensuring the absence of water and contamination in the facility, or allowance for radioactive decay of the packages. The results obtained are continually compiled in reports substantiating the design options. These studies should also lead to an overall economic assessment in terms of the capital and operating cost requirements, thereby providing an additional basis for selecting the design options. The comparison with existing industrial facilities highlights the technical and economic progress represented by the new generation of interim storage units. (authors)

Influencia del yeso sobre la velocidad de hidratación del cemento portland

Directory of Open Access Journals (Sweden)

Yamaguchi, G.

1961-12-01

Full Text Available Not availablePara esclarecer la Influencia del yeso sobre el fraguado y endurecimiento del cemento, los autores estudiaron el grado de hidratación de los cuatro principales minerales del clínker de cemento Portland y el efecto del yeso sobre ellas. Haciendo uso del análisis cuantitativo de rayos X, se determinó la porción no hidratada. Simultáneamente, se determinaron los tiempos de fraguado y las resistencias. Los ensayos se llevaron a cabo sobre tres clínkeres sintéticos de diferentes composiciones y sobre dos clínkeres de cemento Portland comerciales.

A randomized clinical trial on the use of medical Portland cement, MTA and calcium hydroxide in indirect pulp treatment.

Science.gov (United States)

Petrou, Marina Agathi; Alhamoui, Fadi Alhaddad; Welk, Alexander; Altarabulsi, Mohammed Basel; Alkilzy, Mohammed; H Splieth, Christian

2014-01-01

Studies on indirect pulp treatment (IPT) show varying success rates of 73 to 97 %. The necessity of re-opening the cavity and the question of the optimal capping material is still under debate. The aim of this prospective in vivo study was to compare the clinical and microbiological outcomes of mineral trioxide aggregate (MTA), medical Portland cement, and calcium hydroxide on the dentin-pulp complex of permanent and primary teeth treated with two-step IPT. In 86 regular patients (51 % men; 49 % women; age 17.2 years ±13.8), one deep carious lesion each was treated with incomplete caries removal, randomly selected capping with either calcium hydroxide (n = 31), medical Portland cement (29) or white MTA (26), and re-entry (6.3 months ±1.0). Clinical (color, humidity, and consistency of dentin) and microbiological (Lactobacilli/Mutans Strep. counts) parameters were recorded at the first and second treatment. The IPT had a high success rate of 90.3 % regardless of the material used (p = 0.72). The arrested lesions showed consistently darker, dry, and therefore, sclerotic dentine (p Portland cement. The findings of this study could promote the improvement of the IPT as a one-step treatment of deep carious lesions when the remaining demineralized dentin would be sealed with durable restorations.

Durabilidad de un suelo contaminado y tratado con cemento portland Durability of a contaminated soil treated with portland cement

Directory of Open Access Journals (Sweden)

José W Jiménez Rojas

2008-01-01

Full Text Available Este trabajo tiene por objetivo la aplicación de la técnica de solidificación/estabilización de suelos contaminados, analizando específicamente el comportamiento físico del suelo a través de ensayos de durabilidad. El suelo fue contaminado en laboratorio con residuo oleoso y la aplicación de la técnica tuvo cómo agente de encapsulamiento el cemento Portland CP V-ARI. Los ensayos de durabilidad, realizados según la NBR 13554 (1996, tuvieron como objetivo estudiar el grado de desagregación y vulnerabilidad del material con diversas combinaciones de dosificaciones de cemento y residuo oleoso, así cómo estudiar la variación volumétrica de los mismos. A partir de los resultados es posible observar que cuanto mayor la cantidad de contaminante, mayor es la pérdida de masa. Sin embargo, cuánto mayor es la cantidad de cemento, menor es la pérdida de masa y menor la variación volumétrica.This work seeks the application of solidification/stabilization techniques to contaminated soils analyzing specifically de physical behavior of the soil through tests of durability. The soil was contaminated in laboratory with acidic oily sludge industrial residues and the application of that technique had an encapsulate agent, the Portland cement CP V-ARI. The tests were carried out according to NBR 13.554 (1996, and they aimed to study the level of degradation and the vulnerability of the material with several combinations of cement and acidic oily sludge as well as study their volumetric variations. Starting from the results, it is possible to observe that the larger the contamination the larger the mass loss; however the larger the amount of cement, the smaller the mass loss and the more stable the volumetric variation.

The Influence of Diatomite on the Strength and Microstructure of Portland Cement

OpenAIRE

Liu Jun; Shao Peng; Wang Shihao

2016-01-01

To study the influence of the types and mixing amount of diatomite on the Portland cement, we prepared the cement specimen doped with the calcined first-grade, first-grade and second-grade diatomite ,tested the 3d, 7d, 14d compressive strength, and studied and discussed phase, structure and morphology of diatomite in the binary system by the method of XRD, SEM . Experimental results show that with the addition of diatomite, the strength of cement paste increase; the optimal contents of calcin...

Thermodynamic modelling of the effect of temperature on the hydration and porosity of Portland cement

International Nuclear Information System (INIS)

Lothenbach, Barbara; Matschei, Thomas; Moeschner, Goeril; Glasser, Fred P.

2008-01-01

The composition of the phase assemblage and the pore solution of Portland cements hydrated between 0 and 60 deg. C were modelled as a function of time and temperature. The results of thermodynamic modelling showed a good agreement with the experimental data gained at 5, 20, and 50 deg. C. At 5 and at 20 deg. C, a similar phase assemblage was calculated to be present, while at approximately 50 deg. C, thermodynamic calculations predicted the conversion of ettringite and monocarbonate to monosulphate. Modelling showed that in Portland cements which have an Al 2 O 3 /SO 3 ratio of > 1.3 (bulk weight), above 50 deg. C monosulphate and monocarbonate are present. In Portland cements which contain less Al (Al 2 O 3 /SO 3 < 1.3), above 50 deg. C monosulphate and small amounts of ettringite are expected to persist. A good correlation between calculated porosity and measured compressive strength was observed

STABILISASI TANAH LIAT SANGAT LUNAK DENGAN GARAM DAN PC (PORTLAND CEMENT

Directory of Open Access Journals (Sweden)

Tirta Djusman Arief

2006-01-01

Full Text Available Adding sodium chloride, as admixture, and Portland Cement, as stabilizer, to a very soft clay increase its plasticity index (PI, Californian Bearing Ratio (CBR, and Unconfined Compression Strength (UCS. This paper presents the results of testings done to very soft clay from Margomulyo, Surabaya. The results show a promising tendency. Anyhow a wider and comprehensive research is still needed to ensure the long-term effect of the soil stabilization. Abstract in Bahasa Indonesia : Penambahan garam (sodium chloride dan PC (Portland Cement meningkatkan PI (Plasticity Index, CBR (Californian Bearing Ratio, dan UCS (Unconfined Compression Strength dari tanah lempung sangat lunak. Dalam makalah ini disajikan hasil pengujian yang dilakukan terhadap lempung sangat lunak dari daerah Margomulyo, Surabaya. Hasilnya menunjukkan kecenderungan yang menggembirakan, namun penelitian yang luas dan komprehensif masih diperlukan untuk peningkatan stabilitas tanah dalam jangka panjang.

The impact of zirconium oxide radiopacifier on the early hydration behaviour of white Portland cement

International Nuclear Information System (INIS)

Coleman, Nichola J.; Li, Qiu

2013-01-01

Zirconium oxide has been identified as a candidate radiopacifying agent for use in Portland cement-based biomaterials. During this study, the impact of 20 wt.% zirconium oxide on the hydration and setting reactions of white Portland cement (WPC) was monitored by powder X-ray diffraction (XRD), 29 Si and 27 Al magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR), transmission electron microscopy (TEM) and Vicat apparatus. The presence of 20 wt.% zirconium oxide particles in the size-range of 0.2 to 5 μm was found to reduce the initial and final setting times of WPC from 172 to 147 min and 213 to 191 min, respectively. Zirconium oxide did not formally participate in the chemical reactions of the hydrating cement; however, the surface of the zirconium oxide particles presented heterogeneous nucleation sites for the precipitation and growth of the early C-S-H gel products which accelerated the initial setting reactions. The presence of zirconium oxide was found to have little impact on the development of the calcium (sulpho)aluminate hydrate phases. - Highlights: ► This is the first study of Portland cement-based biomaterials by 27 Al and 29 Si NMR. ► 20 wt.% ZrO 2 radiopacifier accelerates the early cement hydration reactions. ► Extent of hydration after 6 h is increased from 5.7% to 15% in the presence of ZrO 2 . ► Initial and final setting times are reduced by 25 and 22 min, respectively. ► ZrO 2 provides nucleation sites for the precipitation of early hydration products.

Ex vivo assessment of genotoxicity and cytotoxicity in murine fibroblasts exposed to white MTA or white Portland cement with 15% bismuth oxide.

Science.gov (United States)

Zeferino, E G; Bueno, C E S; Oyama, L M; Ribeiro, D A

2010-10-01

To evaluate whether white mineral trioxide aggregate (MTA) or white Portland cement with 15% bismuth oxide were able to induce genetic damage and cellular death ex vivo. Aliquots of 1 × 10(4) murine fibroblasts were incubated at 37 °C for 3 h with MTA (white) or white Portland cement with 15% bismuth oxide, at final concentrations ranging from 10 to 1000 μg mL(-1) individually. Data of three independent repeats from the comet assay and the trypan blue exclusion test were assessed by the one-way anova followed by Tukey's test. Mineral trioxide aggregate or Portland cement containing bismuth oxide did not produce genotoxic effects with respect to the single-cell gel (comet) assay data for all concentrations evaluated. Furthermore, no cytotoxicity was observed for MTA or Portland cement. White MTA or white Portland cement containing 15% bismuth oxide were not genotoxic and cytotoxic. © 2010 International Endodontic Journal.

Single-shell tank interim stabilization risk analysis

International Nuclear Information System (INIS)

Basche, A.D.

1998-01-01

The purpose of the Single-Shell Tank (SST) Interim Stabilization Risk Analysis is to provide a cost and schedule risk analysis of HNF-2358, Rev. 1, Single-Shell Tank Interim Stabilization Project Plan (Project Plan) (Ross et al. 1998). The analysis compares the required cost profile by fiscal year (Section 4.2) and revised schedule completion date (Section 4.5) to the Project Plan. The analysis also evaluates the executability of the Project Plan and recommends a path forward for risk mitigation

Microstructure: Surface and cross-sectional studies of hydroxyapatite formation on the surface of white Portland cement paste in vitro

International Nuclear Information System (INIS)

Chaipanich, Arnon; Torkittikul, Pincha

2011-01-01

The formation of hydroxyapatite was investigated at the surface and at the cross-section of white Portland cement paste samples before and after immersion in simulated body fluid. Scanning electron microscope images showed that hydroxyapatite were found at the surface of white Portland cement after immersion in simulated body fluid. Hydroxyapatite grains of mostly ∼1 μm size with some grain size of ∼2-3 μm were seen after 4 days immersion period. More estabilshed hydroxyapatite grain size of ∼3 μm grains were observed at longer period of immersion at 7 and 10 days. The cross-section of the samples was investigated using line scanning technique and was used to determine the hydroxyapatite layer. A strong spectrum of phosphorus is detected up to 6-8 μm depth for samples after 4, 7 and 10 days immersion in simulated body fluid when compared to weak spectrum detected before immersion. The increase in the phosphorus spectrum corresponds to the hydroxyapatite formation on the surface of the samples after the samples were placed in simulated body fluid.

An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

OpenAIRE

Weijing Yao; Jianyong Pang; Yushan Liu

2018-01-01

Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry inject...

EnviroAtlas - Portland, ME - Meter-Scale Urban Land Cover (MULC) Data (2010)

Data.gov (United States)

U.S. Environmental Protection Agency — The EnviroAtlas Portland, ME Meter-Scale Urban Land Cover (MULC) data was generated from USDA NAIP (National Agricultural Imagery Program) four band (red, green,...

Hydration rate and strength development of low-heat type portland cement mortar mixed with pozzolanic materials

International Nuclear Information System (INIS)

Matsui, Jun

1998-01-01

Recently, low-heat type Portland cement was specified in Japan Industrial Standards (JIS). Its hydration proceeds slowly. The results of the research so far obtained indicate that slow hydration of cement and mixing of pozzolanic materials with cement make micro-structure of harded cement paste dense and durable. In this study, a blended cement using low-heat type Portland cement and some of pozzolanic materials has been newly developed and its strength property and hydration ratio were checked. The followings are conclusion. (1) Hydration rate of cement paste varies with the replacement ratio of pozzolanic materials. (2) A good liner relationship between strength and total hydration rate of cement paste was observed. (3) A proper replacement ratio of both base-cement and pozzolanic material for manufacturing a blended cement is 50%. (author)

Phased-Resolved Strain Measuremetns in Hydrated Ordinary Portland Cement Using Synchrotron x-Rays (Prop. 2003-033)

International Nuclear Information System (INIS)

Biernacki, Joseph J.; Watkins, Thomas R.; Parnham, C.J.; Hubbard, Camden R.; Bai, J.

2006-01-01

X-ray diffraction methods developed for the determination of residual stress states in crystalline materials have been applied to study residual strains and strains because of mechanical loading of ordinary portland cement paste. Synchrotron X-rays were used to make in situ measurements of interplanar spacings in the calcium hydroxide (CH) phase of hydrated neat portland cement under uniaxial compression. The results indicate that strains on the order of 1/100 000 can be resolved providing an essentially new technique by which to measure the phase-resolved meso-scale mechanical behavior of cement under different loading conditions. Evaluation of these strain data in view of published elastic parameters for CH suggests that the CH carries a large fraction of the applied stress and that plastic interactions with the matrix are notable.

Gaz de France interim financial report 2007

International Nuclear Information System (INIS)

2007-01-01

This financial report contains the unaudited condensed financial statements of Gaz de France Group for the first half ended June 30, 2007, which were reviewed by the audit committee on August 27, 2007 and by the board of directors at its meeting on August 28, 2007. It includes forward-looking statements concerning the objectives, strategies, financial position, future operating results and the operations of Gaz de France Group. These statements reflect the Group's current perception of its activities and the markets in which it operates, as well as various estimates and assumptions considered to be reasonable. Content: interim management report (highlights of the first half of 2007, revenues and results for the period, financial structure, data on outstanding stock, outlook); interim consolidated financial statements (consolidated statements of income, consolidated balance sheets, consolidated statements of cash flows, recognized income and expenses, statements of changes in shareholders' equity, note to the consolidated financial statements); statement by the person responsible for the interim financial report; statutory auditors' report. (J.S.)

Industrial complementarities between interim storage and reversible geological repository - 59237

International Nuclear Information System (INIS)

Hoorelbeke, Jean-Michel

2012-01-01

The French Act voted in 2006 made the choice of deep geological disposal as the reference option for the long term management of high level (HLW) and intermediate level long-lived waste. The CIGEO repository project aims at avoiding or limiting burden to future generations, which could not be achieved by the extension in time of interim storage. The reversibility as provided by the Act will maintain a liberty of choice for waste management on a duration which is comparable to new storage facility. Interim storage is required to accommodate waste as long as the repository is not available. The commissioning of the repository in 2025 will not suppress needs for interim storage. The paper describes the complementarities between existing and future interim storage facilities and the repository project: repository operational issues and planning, HLW thermal decay, support for the reversibility, etc. It shows opportunities to prepare a global optimization of waste management including the utilization at best of storage capacities and the planning of waste emplacement in the repository in such a way to facilitate operational conditions and to limit cost. Preliminary simulations of storage-disposal scenarios are presented. Thanks to an optimal use of the waste management system, provision can be made for a progressive increase of waste emplacement flow during the first operation phase of the repository. It is then possible to stabilize the industrial activity level of the repository site. An optimal utilization of interim storage can also limit the diversity of waste packages emplaced simultaneously, which facilitates the operation of the repository. 60 years minimum interim storage duration is generally required with respect to HLW thermal output. Extending this interim storage period may reduce the underground footprint of the repository. Regarding reversibility, the capability to manage waste packages potentially retrieved from the repository should be analyzed. The

An Australian Study Comparing the Use of Multiple-Choice Questionnaires with Assignments as Interim, Summative Law School Assessment

Science.gov (United States)

Huang, Vicki

2017-01-01

To the author's knowledge, this is the first Australian study to empirically compare the use of a multiple-choice questionnaire (MCQ) with the use of a written assignment for interim, summative law school assessment. This study also surveyed the same student sample as to what types of assessments are preferred and why. In total, 182 undergraduate…

Fire Hazards Analysis for the 200 Area Interim Storage Area

International Nuclear Information System (INIS)

JOHNSON, D.M.

2000-01-01

This documents the Fire Hazards Analysis (FHA) for the 200 Area Interim Storage Area. The Interim Storage Cask, Rad-Vault, and NAC-1 Cask are analyzed for fire hazards and the 200 Area Interim Storage Area is assessed according to HNF-PRO-350 and the objectives of DOE Order 5480 7A. This FHA addresses the potential fire hazards associated with the Interim Storage Area (ISA) facility in accordance with the requirements of DOE Order 5480 7A. It is intended to assess the risk from fire to ensure there are no undue fire hazards to site personnel and the public and to ensure property damage potential from fire is within acceptable limits. This FHA will be in the form of a graded approach commensurate with the complexity of the structure or area and the associated fire hazards

Physical protection of shipments of irradiated reactor fuel; Interim guidance. Regulatory report

International Nuclear Information System (INIS)

1980-06-01

During May, 1979, the U.S. Nuclear Regulatory Commission approved for issuance in effective form new interim regulations for strengthening the protection of spent fuel shipments against sabotage and diversion. The new regulations were issued without benefit of public comment, but comments from the public were solicited after the effective date. Based upon the public comments received, the interim regulations were amended and reissued in effective form as a final interim rule in May, 1980. The present document supersedes a previously issued interim guidance document, NUREG-0561 (June, 1979) which accompanied the original rule. This report has been revised to conform to the new interim regulations on the physical protection of shipments of irradiated reactor fuel which are likely to remain in effect until the completion of an ongoing research program concerning the response of spent fuel to certain forms of sabotage, at which time the regulations may be rescinded, modified or made permanent, as appropriate. This report discusses the amended regulations and provides a basis on which licensees can develop an acceptable interim program for the protection of spent fuel shipments

Use of alternative dispute resolution--HHS. Notice of interim policy.

Science.gov (United States)

1992-10-27

The Department has developed an interim policy to address the use of alternative dispute resolution (ADR) as required by the Administrative Dispute Resolution Act (ADR Act), Public Law No. 101-552. This interim policy also responds to the Negotiated Rulemaking Act, Public Law No. 101-648, and relevant elements of the Executive Order on Civil Justice Reform (E.O. 12778). The Department is adopting an interim policy because we need a baseline of experience and knowledge from our own pilot activities and those of other agencies before finalizing a policy.

50 CFR 660.720 - Interim protection for sea turtles.

Science.gov (United States)

2010-10-01

... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Interim protection for sea turtles. 660.720 Section 660.720 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... Migratory Fisheries § 660.720 Interim protection for sea turtles. (a) Until the effective date of §§ 660.707...

Setting time and flowability of accelerated Portland cement mixed with polycarboxylate superplasticizer.

Science.gov (United States)

Wongkornchaowalit, Norachai; Lertchirakarn, Veera

2011-03-01

Important limitations of mineral trioxide aggregate for use in clinical procedures are extended setting time and difficult handling characteristics. The removal of gypsum at the end stage of the Portland cement manufacturing process and polycarboxylate superplasticizer admixture may solve these limitations. Different concentrations of polycarboxylate superplasticizer (0%, 1.2%, 1.8%, and 2.4% by volume) and liquid-to-powder ratios (0.27, 0.30, and 0.33 by weight) were mixed with white Portland cement without gypsum (AWPC-experimental material). Type 1 ordinary white Portland cement mixed with distilled water at the same ratios as the experimental material was used as controls. All samples were tested for setting time and flowability according to the International Organization for Standardization 6876:2001 guideline. The data were analyzed by two-way analysis of variance. Then, one-way analysis of variance and multiple comparison tests were used to analyze the significance among groups. The data are presented in mean ± standard deviation values. In all experimental groups, the setting times were in the range of 4.2 ± 0.4 to 11.3 ± 0.2 minutes, which were significantly (p setting time and increased flowability of cement, which would be beneficial for clinical use. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

CMM Interim Check (U)

Energy Technology Data Exchange (ETDEWEB)

Montano, Joshua Daniel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2015-03-23

Coordinate Measuring Machines (CMM) are widely used in industry, throughout the Nuclear Weapons Complex and at Los Alamos National Laboratory (LANL) to verify part conformance to design definition. Calibration cycles for CMMs at LANL are predominantly one year in length. Unfortunately, several nonconformance reports have been generated to document the discovery of a certified machine found out of tolerance during a calibration closeout. In an effort to reduce risk to product quality two solutions were proposed – shorten the calibration cycle which could be costly, or perform an interim check to monitor the machine’s performance between cycles. The CMM interim check discussed makes use of Renishaw’s Machine Checking Gauge. This off-the-shelf product simulates a large sphere within a CMM’s measurement volume and allows for error estimation. Data was gathered, analyzed, and simulated from seven machines in seventeen different configurations to create statistical process control run charts for on-the-floor monitoring.

Improved quantification of alite and belite in anhydrous Portland cements by 29Si MAS NMR: Effects of paramagnetic ions

DEFF Research Database (Denmark)

Poulsen, Søren Lundsted; Kocaba, Vanessa; Le Saoût, Gwenn

2009-01-01

The applicability, reliability, and repeatability of 29Si MAS NMR for determination of the quantities of alite (Ca3SiO5) and belite (Ca2SiO4) in anhydrous Portland cement was investigated in detail for 11 commercial Portland cements and the results compared with phase quantifications based...

Interim process report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Sellin, Patrick

2004-08-01

This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses

Interim process report for the safety assessment SR-Can

Energy Technology Data Exchange (ETDEWEB)

Sellin, Patrick (ed.)

2004-08-01

This report is a documentation of buffer processes identified as relevant to the long-term safety of a KBS-3 repository. The report is part of the interim reporting of the safety assessment SR-Can, see further the Interim main report. The final SR-Can reporting will support SKB's application to build an Encapsulation plant for spent nuclear fuel and is to be produced in 2006. The purpose of this report is to document the scientific knowledge of the processes to a level required for an adequate treatment in the safety assessment. The documentation is thus from a scientific point of not exhaustive since such a treatment is neither necessary for the purposes of the safety assessment nor possible within the scope of an assessment. The purpose is further to determine the handling of each process in the safety assessment and to demonstrate how uncertainties are taken care of, given the suggested handling. The process documentation in the SR 97 version of the Process report is a starting point for this SR-Can interim version. As further described in the Interim main report, the list of relevant processes has been reviewed and slightly extended by comparison to other databases. Furthermore, the backfill has been included as a system part of its own, rather than being described together with the buffer as in SR 97. Apart from giving an interim account of the documentation and handling of buffer processes in SR-Can, this report is meant to serve as a template for the forthcoming documentation of processes occurring in other parts of the repository system. A complete list of processes can be found in the Interim FEP report for the safety assessment SR-Can. All material presented in this document is preliminary in nature and will possibly be updated as the SR-Can project progresses.

Individual shareholders’ understanding of the content of interim reports of South African listed retail companies

Directory of Open Access Journals (Sweden)

Johan GI Oberholster

2015-05-01

Full Text Available A number of studies conducted, and reports published, by international and local accounting bodies have found that the proliferation of disclosures in financial reports has hampered users’ understanding of these reports. The reports by accounting bodies also indicate that these users prefer more concise financial reports. These findings, in conjunction with a dearth of recent questionnaire-based research on whether individual shareholders understand the content of financial reports, resulted in this study on whether individual shareholders understand the content of interim reports. The study provides empirical proof that a sound knowledge of business, accounting and economic matters is a prerequisite for understanding interim reports in the case of individual shareholders. The results of the study indicate that individual shareholders have a limited understanding of the content of interim reports as a whole, and that a good knowledge of business and economic matters and of accounting results in an improved understanding of the content of interim reports. In particular, specialisation in accounting in undergraduate and postgraduate degrees, professional qualifications, and work experience in the financial field improve the understanding of individual shareholders.

Prediction of potential compressive strength of Portland clinker from its mineralogy

DEFF Research Database (Denmark)

Svinning, K.; Høskuldsson, Agnar; Justnes, H.

2010-01-01

Based on a statistical model first applied for prediction of compressive strength up to 28 d from the microstructure of Portland cement, potential compressive strength of clinker has been predicted from its mineralogy. The prediction model was evaluated by partial least squares regression...

Effectiveness of shrinkage-reducing admixtures on Portland pozzolan cement concrete

Directory of Open Access Journals (Sweden)

Videla, C.

2005-06-01

Full Text Available Drying shrinkage causes tensile stress in restrained concrete members. Since all structural elements are subject to some degree of restraint, drying shrinkage is regarded to be one of the main causes of concrete cracking. The purpose of the present study was to evaluate the effectiveness of SRA in reducing drying shrinkage strain in Portland pozzolan cement concrete. The major variables examined included slump, admixture type and dose, and specimen size. The measured results indicate that any of the admixtures used in the study significantly reduced shrinkage. Concrete manufactured with shrinkage reducing admixtures shrank an average of 43% less than concrete without admixtures. As a rule, the higher the dose of admixture, the higher was its shrinkage reduction performance. The experimental results were compared to the shrinkage strain estimated with the ACI 209, CEB MC 90, B3, GL 2000, Sakata 1993 and Sakata 2001 models. Although none of these models was observed to accurately describe the behaviour of Portland pozzolan cement concrete with shrinkage reducing admixtures, the Sakata 2001 model, with a weighted coefficient of variation of under 30%, may be regarded to be roughly adequate.

La retracción por secado es un fenómeno intrínseco del hormigón que produce tensiones de tracción en elementos restringidos de hormigón. Puesto que todos los elementos presentan algún grado de retracción, se considera a la retracción por secado como una de las principales causas de agrietamiento en proyectos de construcción en hormigón. Por lo tanto, el objetivo de esta investigación fue evaluar la efectividad de los aditivos reductores de retracción (SRA en hormigones fabricados con cemento Portland puzolánico. Las variables principales estudiadas incluyen el asentamiento de cono de Abrams, marca y dosis de aditivo reductor de retracción, y tamaño de espécimen de hormigón. Los resultados obtenidos permiten concluir que el uso de

Development of the Portland cement slurries with diatomaceous earth to the oil industry; Desenvolvimento de pastas de cimento Portland com adicao de diatomita para a industria do petroleo

Energy Technology Data Exchange (ETDEWEB)

Brito, Roseane A; Melo, Dulce M.A.; Martinelli, Antonio E.; Simao, Cristina A.; Paiva, Maria D.M. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Melo, Marcus A.F. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)

2004-07-01

The class-G Portland cement has been used with success in oil well cementing. The material is usually shipped to the Northeast Brazil, because the only plant that manufactures class-G is located in Cantagalo/RJ. The present work investigates the influence of the partial substitution of Portland cement by diatomaceous earth, aiming at reducing the costs in oil well cementing, improving the slurry properties and using local raw material. The diatomaceous earth has pozzolanic properties and can be used as extenders of cement slurries. This properties added to the lower cost and availability of this material in Northeast Brazil, make the diatomaceous earth a candidate material to produce light cements, to well conditions in advanced phases of production. It were evaluated the rheological properties of the slurries (at 25 and 52 deg C), volume of free water, compressive strength after curing for 8, 24 and 48 h at 38 deg C, and consistometry tests. The results show that the diatomaceous earth maintain the viscosity values and gel force suitable for use in oil well cementing. No free water was observed in the formulations. It was also verified that the compressive strength of slurries hardened with diatomaceous earth is similar to those with only Portland cement and that the minimum compressive strength of 300 psi, after curing for 8 h was reached. The thickening time was longer than the average value and the application value. (author)

Microscopic analysis of dog dental pulp after pulpotomy and pulp protection with mineral trioxide aggregate and white Portland cement Análise microscópica da polpa dental de cães após pulpotomia e proteção pulpar com agregado de trióxido mineral e cimento Portland branco

Directory of Open Access Journals (Sweden)

Renato Menezes

2004-06-01

Full Text Available Considering previous studies on the similarity between the chemical composition of the mineral trioxide aggregate and the Portland cement, the purpose of this study was to investigate the pulp response of dog's teeth after pulpotomy and direct pulp protection with MTA Angelus and white Portland cement. Thirty eight pulp remnants were protected with these materials. One hundred and twenty days after treatment, the animals were sacrificed and the specimens removed and prepared for histological analysis. Both materials demonstrated the same results when used as pulp capping materials, inducing hard tissue bridge formation and maintaining pulp vitality in all specimens. The MTA Angelus and the white Portland cement showed to be effective as pulp protection materials following pulpotomy.Considerando estudos anteriores sobre a similaridade entre a composição química do agregado de trióxido mineral e o cimento Portland, o objetivo deste estudo foi investigar a resposta pulpar de dentes de cães após pulpotomia e proteção pulpar direta com MTA Angelus e cimento Portland branco. Trinta e oito remanescentes pulpares foram recobertos com esses materiais. Cento e vinte dias após o tratamento, os animais foram sacrificados e os espécimes removidos e preparados para análise histológica. Ambos os materiais demonstraram os mesmos resultados quando utilizados como materiais de capeamento pulpar, induzindo a formação de ponte de tecido mineralizado e mantendo a vitalidade pulpar em todos os espécimes. Ambos matérias se mostraram efetivos como protetores pulpares após pulpotomia em dentes de cães.

Materials behavior in interim storage of spent fuel

International Nuclear Information System (INIS)

Johnson, A.B. Jr.; Bailey, W.J.; Gilbert, E.R.; Inman, S.C.

1982-01-01

Interim storage has emerged as the only current spent-fuel management method in the US and is essential in all countries with nuclear reactors. Materials behavior is a key aspect in licensing interim-storage facilities for several decades of spent-fuel storage. This paper reviews materials behavior in wet storage, which is licensed for light-water reactor (LWR) fuel, and dry storage, for which a licensing position for LWR fuel is developing

Interim Safety Basis for Fuel Supply Shutdown Facility

International Nuclear Information System (INIS)

BENECKE, M.W.

2000-01-01

This ISB, in conjunction with the IOSR, provides the required basis for interim operation or restrictions on interim operations and administrative controls for the facility until a SAR is prepared in accordance with the new requirements or the facility is shut down. It is concluded that the risks associated with tha current and anticipated mode of the facility, uranium disposition, clean up, and transition activities required for permanent closure, are within risk guidelines

Study of radon diffusion from RHA-modified ordinary Portland cement using SSNTD technique

International Nuclear Information System (INIS)

Narula, A.K.; Goyal, S.K.; Chauhan, R.P.; Chakarvarti, S.K.

2013-01-01

The diffusion coefficient of radon is a very important factor in estimating the rate of indoor radon inflow. The aim of this work is to develop and assess the potential of radon resistant construction materials in residential buildings. Of late, rice husk ash (RHA) has been used as a component in cement. The X-ray diffraction of RHA indicates that the RHA contains mainly amorphous materials while the X-ray fluorescence analysis shows that the major percentage of it is composed of silica. The amorphous silica present in the RHA is responsible for the pozzolonic activity of the ash. The results of the present study indicate that the RHA when mixed with cement initially reduces radon diffusion coefficient, followed by enhancement when the percentage of RHA is increased above 30% by weight. - Highlights: ► Radon diffusion coefficient has been measured in Portland cement with different percentage of rice husk ash (RHA). ► The mixing of RHA to cement changes the radon diffusion coefficient. ► The mixture of cement and RHA can be used to make building materials more resistant to radon entry through diffusion

78 FR 49782 - Interim Staff Guidance on Changes During Construction

Science.gov (United States)

2013-08-15

... Construction AGENCY: Nuclear Regulatory Commission. ACTION: Draft interim staff guidance; request for comment... During Construction.'' This ISG provides guidance to the NRC staff on the Preliminary Amendment Request...-ISG-025 ``Interim Staff Guidance on Changes during Construction under 10 CFR Part 52'' is available...

Chemical composition, effective atomic number and electron density study of trommel sieve waste (TSW), Portland cement, lime, pointing and their admixtures with TSW in different proportions

International Nuclear Information System (INIS)

Kurudirek, Murat; Aygun, Murat; Erzeneoglu, Salih Zeki

2010-01-01

The trommel sieve waste (TSW) which forms during the boron ore production is considered to be a promising building material with its use as an admixture with Portland cement and is considered to be an alternative radiation shielding material, also. Thus, having knowledge on the chemical composition and radiation interaction properties of TSW as compared to other building materials is of importance. In the present study, chemical compositions of the materials used have been determined using a wavelength dispersive X-ray fluorescence spectrometer (WDXRFS). Also, TSW, some commonly used building materials (Portland cement, lime and pointing) and their admixtures with TSW have been investigated in terms of total mass attenuation coefficients (μ/ρ), photon interaction cross sections (σ t ), effective atomic numbers (Z eff ) and effective electron densities (N e ) by using X-rays at 22.1, 25 keV and γ-rays at 88 keV photon energies. Possible conclusions were drawn with respect to the variations in photon energy and chemical composition.

Addition of polyurethane dispersions to Portland G for oil wells steam injection submitted to vapor injection; Adicao de poliuretana em dispersao a Portland G para cimentacao de pocos de petroleo sujeitos a injecao de vapor

Energy Technology Data Exchange (ETDEWEB)

Silva, L.B. da; Lima, F.M. de; Martinelli, A.M.; Bezerra, U.T.; Mello, D.M.A. [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil); Araujo, R.G.S. [PETROBRAS, Rio de Janeiro, RJ (Brazil)

2004-07-01

Portland cement is by far the most important binding material used in oil well cementing. The cement sheath is responsible for both the mechanical stability of the wellbore and zonal isolation. During primary cementing and the production lifespan of the well, the cement sheath is exposed to adverse thermo-mechanical conditions, which may crack the intrinsically brittle cement material. Cracking affects the mechanical integrity of the sheath resulting in the contamination of oil or gas pay zones, as well as in the increase of producing costs related to the extraction of pebble and water. This scenario is especially encountered in wells containing heavy oils, typical of the Northeastern region of Brazil. The objective of the present study was to improve the fracture toughness of hardened Special Portland Cement slurries by the addition of aqueous polyurethane to Portland-based slurries used in primary cementing, plug backs and squeeze operations, improving environmental and economical impacts. The results revealed that the addition of polyurethane increased the viscosity of the slurry but still within the limits established by oil well cement guidelines. No significant increase was observed in the compressive strength of the cement. However, the addition of polyurethane improved the toughness of the cement increasing its ability to withstand thermo-mechanical cycles typical of heavy oil recovery. In addition, significant reduction in permeability was observed as the contents of polyurethane increased, contributing to the reduction in set time and gas migration through the cement sheath. (author)

An Experimental Study of Portland Cement and Superfine Cement Slurry Grouting in Loose Sand and Sandy Soil

Directory of Open Access Journals (Sweden)

Weijing Yao

2018-04-01

Full Text Available Grouting technology is widely applied in the fields of geotechnical engineering in infrastructure. Loose sand and sandy soil are common poor soils in tunnel and foundation treatments. It is necessary to use superfine cement slurry grouting in the micro-cracks of soil. The different effectiveness of Portland cement slurry and superfine cement slurry in sandy soil by the laboratory grouting experiment method were presented in this paper. The grouting situations of superfine cement slurry injected into sand and sandy soil were explored. The investigated parameters were the dry density, wet density, moisture content, internal friction angle, and cohesion force. The results show that the consolidation effect of superfine cement is better than that of Portland cement due to the small size of superfine cement particles. The superfine cement can diffuse into the sand by infiltration, extrusion, and splitting. When the water–cement ratio of superfine cement slurry is less than 2:1 grouting into loose sand, the dry and wet density decrease with the increase in the water–cement ratio, while the moisture content and cohesive force gradually increase. When the water–cement ratio of superfine cement slurry is 1:1 grouting into loose sand and sandy soil, the dry density, wet density, and cohesive force of loose sand are larger than those of sandy soil. The results of the experiment may be relevant for engineering applications.

Final Rule: NESHAP for the Portland Cement Manufacturing Industry: Alternative Monitoring Method

Science.gov (United States)

EPA is extending its approval for the use of an alternative method to show compliance with hydrogen chloride (HCl) emissions limits in the National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry

Spent fuel interim management: 1995 update

International Nuclear Information System (INIS)

Anderson, C.K.

1995-01-01

The problems of interim away-from-reactor spent fuel storage and storage in spent fuel pools at the reactor site are discussed. An overview of the state-of-the-art in the USA, Europe, and Japan is presented. The technical facilities for away-from-reactor storage are briefly described, including wet storage pools, interactive concrete systems, metallic containers, and passive concrete systems. Reprocessing technologies are mostly at the design stage only. It is predicted that during the 20 years to come, about 50 000 tonnes of spent fuel will be stored at reactor sites regardless of the advance of spent fuel reprocessing or interim storage projects. (J.B.). 4 tabs., 2 figs

General certification procedure of enterprises and interim job enterprises

CERN Document Server

Int. At. Energy Agency, Wien

2002-01-01

This procedure defines the certification global process of enterprises employing workers of A or B category for nuclear facilities and interim job enterprises proposing workers of A or B category for nuclear facilities. This certification proves the enterprises ability to satisfy the specification ''E'' of the CEFRI and the interim job enterprises to satisfy the specification ''I'' of the CEFRI. (A.L.B.)

ITER interim design report package and relevant documents

International Nuclear Information System (INIS)

1996-01-01

This publication documents the technical basis which underlay the Interim Design Report, Cost Review and Safety Analysis submitted to the ITER Councils (IC-8 and IC-9) Records of decisions and the ''ITER Interim Design Report Package''. This publication contains ITER Site Requirements and ITER Site Design Assumptions, TAC-8 Report, SRG Report, CP's Report on Tentative Sequence of Events and Parties' Views on the IDR Package and Parties' Technical Comments on the IDR Package. Figs, tabs

Tribal child welfare. Interim final rule.

Science.gov (United States)

2012-01-06

The Administration for Children and Families (ACF) is issuing this interim final rule to implement statutory provisions related to the Tribal title IV-E program. Effective October 1, 2009, section 479B(b) of the Social Security Act (the Act) authorizes direct Federal funding of Indian Tribes, Tribal organizations, and Tribal consortia that choose to operate a foster care, adoption assistance and, at Tribal option, a kinship guardianship assistance program under title IV-E of the Act. The Fostering Connections to Success and Increasing Adoptions Act of 2008 requires that ACF issue interim final regulations which address procedures to ensure that a transfer of responsibility for the placement and care of a child under a State title IV-E plan to a Tribal title IV-E plan occurs in a manner that does not affect the child's eligibility for title IV-E benefits or medical assistance under title XIX of the Act (Medicaid) and such services or payments; in-kind expenditures from third-party sources for the Tribal share of administration and training expenditures under title IV-E; and other provisions to carry out the Tribal-related amendments to title IV-E. This interim final rule includes these provisions and technical amendments necessary to implement a Tribal title IV-E program.

Evaluation of the effect of intrinsic material properties and ambient conditions on the dimensional stability of white mineral trioxide aggregate and Portland cement.

Science.gov (United States)

Camilleri, Josette

2011-02-01

A number of factors affect the dimensional stability of a material. These factors include curing conditions, material solubility, leaching, and time. The aim of this study was to evaluate the restrained dimensional change in the vertical direction as a function of the ambient conditions, fluid uptake, solubility, and leaching of white mineral trioxide aggregate (MTA) and Portland cement stored in Hank's balanced salt solution (HBSS) over a period of 28 days. The dimensional change in the vertical direction over a 28-day period was determined using a linear variable differential transducer (LVDT) on laterally restrained test samples. The fluid uptake and solubility of both MTA and Portland cement was also evaluated. The leaching in water and HBSS was assessed using inductively coupled plasma. MTA was more soluble than Portland cement. Both materials absorbed water and physiological solution, with Portland cement displaying a lower uptake than MTA. Both cements exhibited a net expansion when in contact with a physiological solution and released high levels of calcium. MTA leached bismuth. Both calcium and bismuth ion release was higher in HBSS than in water. Phosphorus ions in HBSS were depleted when in contact with both MTA and Portland cement. The MTA was very susceptible to ambient conditions. The addition of bismuth oxide to MTA reduced the leaching of calcium hydroxide, increased the material solubility, and caused deterioration in material dimensional stability. Further research is necessary to establish the material porosity and its effect on the dimensional stability. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Portland cement concrete pavement review of QC/QA data 2000 through 2009.

Science.gov (United States)

2011-04-01

This report analyzes the Quality Control/Quality Assurance (QC/QA) data for Portland cement concrete pavement : (PCCP) awarded in the years 2000 through 2009. Analysis of the overall performance of the projects is accomplished by : reviewing the Calc...

30 CFR 827.13 - Coal preparation plants: Interim performance standards.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Coal preparation plants: Interim performance...-COAL PREPARATION PLANTS NOT LOCATED WITHIN THE PERMIT AREA OF A MINE § 827.13 Coal preparation plants: Interim performance standards. (a) Persons operating or who have operated coal preparation plants after...

Fast Flux Test Facility interim examination and maintenance cell: Past, present, and future

International Nuclear Information System (INIS)

Vincent, J.R.

1990-09-01

The Fast Flux Test Facility Interim Examination and Maintenance Cell was designed to perform interim examination and/or disassembly of experimental core components for final analysis elsewhere, as well as maintenance of sodium-wetted or neutron-activated internal reactor parts and plant support hardware. The Interim Examination and Maintenance Cell equipment developed and used for the first ten years of operation has been primarily devoted to the disassembly and examination of core component test assemblies. While no major reactor equipment has required remote repair or maintenance, the Interim Examina Examination and Maintenance Cell has served as the remote repair facility for its own in-cell equipment, and several innovative remote repairs have been accomplished. The Interim Examination and Maintenance Cell's demonstrated versatility has shown its capability to support a challenging future. 12 refs., 9 figs

Characteristics of novel root-end filling material using epoxy resin and Portland cement.

Science.gov (United States)

Lee, Sang-Jin; Chung, Jin; Na, Hee-Sam; Park, Eun-Joo; Jeon, Hyo-Jin; Kim, Hyeon-Cheol

2013-04-01

The aim of this study was to evaluate the physical properties and cytotoxicity of a novel root-end filling material (EPC) which is made from epoxy resin and Portland cement as a mineral trioxide aggregate (MTA) substitute. EPC, developed as a root-end filling material, was compared with MTA and a mixture of AH Plus sealer and MTA (AMTA) with regard to the setting time, radio-opacity, and microleakage. Setting times were evaluated using Vicat apparatus. Digital radiographs were taken to evaluate the aluminium equivalent radio-opacity using an aluminium step wedge. Extracted single-rooted teeth were used for leakage test using methylene blue dye. After canal shaping and obturation, the apical 3-mm root was resected, and a root-end cavity with a depth of 3 mm was prepared. The root-end cavities were filled with MTA, AMTA, and EPC for 15 specimens in each of three groups. After setting in humid conditions for 24 h, the specimens were tested for apical leakage. For evaluation of the biocompatibility of EPC, cell (human gingival fibroblast) viability was compared for MTA and Portland cement by MTT assay, and cell morphological changes were compared for MTA and AH Plus by fluorescence microscopy using DAPI and F-actin staining. The setting time, radio-opacity, and microleakage were compared using one-way ANOVA and Scheffe's post hoc comparison, and the cytotoxicity was compared using the nonparametric Kruskal-Wallis rank sum test. Statistical significance was set at 95%. EPC had a shorter setting time and less microleakage compared with MTA (p Portland cement, was found to be a useful material for root-end filling, with favourable radio-opacity, short setting time, low microleakage, and clinically acceptable low cytotoxicity. The novel root-end filling material would be a potentially useful material for a surgical endodontic procedure with favourable properties.

Natural cement as the precursor of Portland cement: Methodology for its identification

International Nuclear Information System (INIS)

Varas, M.J.; Alvarez de Buergo, M.; Fort, R.

2005-01-01

When cements appeared in the 19th century, they took the place of traditional binding materials (lime, gypsum, and hydraulic lime) which had been used until that time. Early cements can be divided into two groups, natural and artificial (Portland) cements. Natural cements were introduced first, but their widespread usage was short-lived as they were quickly replaced by artificial cements (Portland), still the most important and predominant today. The main differences between natural and artificial cements arise during the manufacturing process. The final properties of the cements are greatly influenced by differences in the raw materials and burning temperatures employed. The aim of this paper is to assess the efficiency of traditional analytical techniques (petrographic microscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR)) used to differentiate natural and artificial cements

Early hydration of portland cement with crystalline mineral additions

International Nuclear Information System (INIS)

Rahhal, V.; Talero, R.

2005-01-01

This research presents the effects of finely divided crystalline mineral additions (quartz and limestone), commonly known as filler, on the early hydration of portland cements with very different mineralogical composition. The used techniques to study the early hydration of blended cements were conduction calorimeter, hydraulicity (Fratini's test), non-evaporable water and X-ray diffraction. Results showed that the stimulation and the dilution effects increase when the percentage of crystalline mineral additions used is increased. Depending on the replacement proportion, the mineralogical cement composition and the type of crystalline addition, at 2 days, the prevalence of the dilution effect or the stimulation effect shows that crystalline mineral additions could act as sites of heat dissipation or heat stimulation, respectively

Four Decades of Systems Science Teaching and Research in the USA at Portland State University

Directory of Open Access Journals (Sweden)

Wayne Wakeland

2014-04-01

Full Text Available Systems science is defined in general fashion, and a brief background is provided that lists some of the systems science-related societies, conferences, journals, research institutes, and educational programs. The Systems Science Graduate Program at Portland State University in Portland, OR, USA, is described in detail, including its history, curriculum, students, faculty, and degrees granted. Dissertation topics are summarized via word diagrams created from dissertation titles over the years. MS degrees, student placement, and undergraduate courses are also mentioned, and future plans for the program are described including its support for sustainability education.

Recycled Portland cement concrete pavements : Part II, state-of-the art summary.

Science.gov (United States)

1979-01-01

This report constitutes a review of the literature concerning recycling of portland cement concrete pavements by crushing the old pavement and reusing the crushed material as aggregate in a number of applications. A summary of the major projects cond...

216-T-4 interim stabilization final report

International Nuclear Information System (INIS)

Smith, D.L.

1996-01-01

This report provides a general description of the activities performed for the interim stabilization of the 216-T-4-1 ditch, 216-T-4-2 ditch, and 216-T-4-2 pond. Interim stabilization was required to reduce the amount of surface-contaminated acres and to minimize the migration of radioactive contamination. Work associated with the 216-T4-1 ditch and 216-T-4-2 pond was performed by the Radiation Area Remedial Action (RARA) Project. Work associated with the 216-T-4-2 ditch was done concurrently but was funded by Westinghouse Hanford Company (WHC) Tank Waste Remediation Systems (TWRS)

Lessons for outsourcing and interim management relationships.

Science.gov (United States)

Macko, W; Kostyack, P T

1999-01-01

Few decisions can affect an organization more than the selection of an outsourcing or interim management partner. More and more health care organizations face such decisions in today's competitive market in order to face new business needs. Making these relationships successful can be important for health care organizations seeking competitive advantages or seeking immediately accessible management support. These relationships, however, require careful partner selection and development. Success in outsourcing and interim management relationships is contingent upon a thorough selection process, a strong contract that has clearly and explicitly detailed responsibilities and a culture-sensitive business rapport between the client and selected partner.

Do Interim Assessments Reduce the Race and SES Achievement Gaps?

Science.gov (United States)

Konstantopoulos, Spyros; Li, Wei; Miller, Shazia R.; van der Ploeg, Arie

2017-01-01

The authors examined differential effects of interim assessments on minority and low socioeconomic status students' achievement in Grades K-6. They conducted a large-scale cluster randomized experiment in 2009-2010 to evaluate the impact of Indiana's policy initiative introducing interim assessments statewide. The authors used 2-level models to…

Effect of silica fume on reaction products of uranium (VI) with portland cement

International Nuclear Information System (INIS)

Tan Hongbin; Shaanxi Univ. of Technology, Hanzhong; Li Yuxiang

2005-01-01

Simulation of radioactive waste of U(VI) by uranyl nitrate and the effects of different additive quantities (12%, 20%, 30%, 35%, 40%) of silica fume on the products of U(VI) with Portland cement were studied at a hydrothermal condition of 180 degree C for a duration of one week. The X-ray powder diffraction examination results showed that the calcium uranate would be transformed into uranophane when the cement contained 30% silica fume. (authors)

Evaluation of the use of red mud as a pozzolanic additive in Portland cement

International Nuclear Information System (INIS)

Fortes, Gustavo Mattos; Balbino, Thiago Gabriel Ferreira; Lourenco, Rafaela Roberta; Rodrigues, Jose de Anchieta

2011-01-01

It is estimated that the aluminum industry generates approximately 13.7 million tones/year of red mud (RB) in Brazil. Although, being the RB rich in Al 2 O 3 and SiO 2 and partially amorphous, a potential pozzolanic activity is suggested. Thus, this work aims to evaluate the application of 15w-% of RB, as a pozzolanic additive, to the ordinary Portland cement (CPI), simulating a pozzolanic compost Portland cement (CPII-Z). To study the pozzolanic activation of the RB, this one was added without calcination, calcinated at 400°C and at 600°C. The compressive strength was measured in mortars of CPI with additions of RB, of CPI and CPII (references), after 28 days of curing. The analysis of the apparent porosity and the characterization of the hydration products were done to complement the evaluation. The mortars with calcinated RB showed good results of mechanical strength, reaching more than 85% (45 MPa) of the CPI's strength and higher values than the CPII-Z32. (author)

Portland blended cements: demolition ceramic waste management

International Nuclear Information System (INIS)

Trezza, M.A.; Zito, S.; Tironi, A.; Irassar, E.F.; Rahhal, V.F.

2017-01-01

Demolition ceramic wastes (DCWs) were investigated in order to determine their potential use as supplementary cementitious materials in Portland Blended Cements (PBCs). For this purpose, three ceramic wastes were investigated. After characterization of the materials used, the effect of ceramic waste replacement (8, 24 and 40% by mass) was analyzed. Pozzolanic activity, hydration progress, workability and compressive strength were determined at 2, 7 and 28 days. The results showed that the ground wastes behave as filler at an early age, but as hydration progresses, the pozzolanic activity of ceramic waste contributes to the strength requirement. [es

Comprehensive Medical Management of Rosacea: An Interim Study Report and Literature Review

OpenAIRE

Del Rosso, James Q.; Baum, Eric W.

2008-01-01

Rosacea is a common inflammatory facial dermatosis seen in adults that exhibits considerable variety in clinical presentation. Multiple medical therapeutic options are available including topical and oral treatments. Optimal medical management of rosacea includes assessment of subtype and disease severity and use of appropriate skin care to reduce epidermal barrier dysfunction. This article provides an overall discussion of the medical management of rosacea and reviews interim results from a ...

Influence of limestone on the hydration of Portland cements

International Nuclear Information System (INIS)

Lothenbach, Barbara; Le Saout, Gwenn; Gallucci, Emmanuel; Scrivener, Karen

2008-01-01

The influence of the presence of limestone on the hydration of Portland cement was investigated. Blending of Portland cement with limestone was found to influence the hydrate assemblage of the hydrated cement. Thermodynamic calculations as well as experimental observations indicated that in the presence of limestone, monocarbonate instead of monosulfate was stable. Thermodynamic modelling showed that the stabilisation of monocarbonate in the presence of limestone indirectly stabilised ettringite leading to a corresponding increase of the total volume of the hydrate phase and a decrease of porosity. The measured difference in porosity between the 'limestone-free' cement, which contained less than 0.3% CO 2 , and a cement containing 4% limestone, however, was much smaller than calculated. Coupling of thermodynamic modelling with a set of kinetic equations which described the dissolution of the clinker, predicted quantitatively the amount of hydrates. The quantities of ettringite, portlandite and amorphous phase as determined by TGA and XRD agreed well with the calculated amounts of these phases after different periods of time. The findings in this paper show that changes in the bulk composition of hydrating cements can be followed by coupled thermodynamic models. Comparison between experimental and modelled data helps to understand in more detail the dominating processes during cement hydration

76 FR 76760 - Gray Portland Cement and Cement Clinker From Japan

Science.gov (United States)

2011-12-08

... and Cement Clinker From Japan Determination On the basis of the record \\1\\ developed in the subject... duty order on gray Portland cement and cement clinker from Japan would be likely to lead to... and Cement Clinker from Japan: Investigation No. 731- TA-461 (Third Review). By order of the...

Durabilidad de un suelo contaminado y tratado con cemento portland Durability of a contaminated soil treated with portland cement

OpenAIRE

José W Jiménez Rojas; Nilo C Consoli; Karla Salvagni Heineck

2008-01-01

Este trabajo tiene por objetivo la aplicación de la técnica de solidificación/estabilización de suelos contaminados, analizando específicamente el comportamiento físico del suelo a través de ensayos de durabilidad. El suelo fue contaminado en laboratorio con residuo oleoso y la aplicación de la técnica tuvo cómo agente de encapsulamiento el cemento Portland CP V-ARI. Los ensayos de durabilidad, realizados según la NBR 13554 (1996), tuvieron como objetivo estudiar el grado de desagregación y v...

Radon in homes of the Portland, Oregon Area: Radon data from local radon testing companies collected by CRM (Continuous Radon Measurement) machines

Science.gov (United States)

Whitney, H.; Lindsey, K.; Linde, T.; Burns, S. F.

2013-12-01

Students from the Department of Geology at Portland State University paired up with the Oregon Health Authority to better understand radon gas values in homes of the Portland metropolitan area. This study focuses on radon values collected by continuous radon measurement (CRM) machines, taken by local radon testing companies. The local companies participating in this study include Alpha Environmental Services, Inc., Cascade Radon, Environmental Works, The House Detectives, LLC, and Soil Solutions Environmental Services, Inc. In total, 2491 radon readings spanning across 77 zip codes were collected from local companies in the Portland metropolitan area. The maximum value, average value, percentage of homes greater than 4 pCi/L and total rank sum was calculated and used to determine the overall radon potential for each zip code (Burns et al., 1998). A list and four maps were produced showing the results from each category. Out of the total records, 24 zip codes resulted in high radon potential and the average reading for the entire Portland Metropolitan area was 3.7 pCi/L. High potential zip codes are thought to be a result of sand and gravel (Missoula Flood deposits) and faults present in the subsurface. The CRM data was compared with both long-term and short-term data provided by the Oregon Health Authority to validate radon potentials in each zip code. If a home is located in a zip code with high or moderate radon potential across two types of data sets, it is recommended that those homes be tested for radon gas.

The Interim Financial Reporting in the Spirit of the IAS 34 Norm

OpenAIRE

Ovidia Doinea

2008-01-01

The role of an interim financial reporting is to allow the information users to acknowledge the activity of an entity on period shorter than financial exercise from the perspective of the available profits and cash flows generated as well as from the point of view of its financial position and liquidity. The interim financial reporting includes a complete or condensed set of financial statements which target to update the last financial reporting, usually the annual report. The interim financ...

Poor predictive value of positive interim FDG-PET/CT in primary mediastinal large B-cell lymphoma

Energy Technology Data Exchange (ETDEWEB)

Lazarovici, Julien; Petrovanu, Cynthia; Danu, Alina; Ferme, Christophe; Ribrag, Vincent; Ghez, David [Gustave Roussy, Villejuif (France). Dept. of Hematology; Paris Saclay Univ., Saint-Aubin (France); Terroir, Marie [Gustave Roussy, Villejuif (France). Dept. of Nuclear Medicine and Endocrine Oncology; Paris Saclay Univ., Saint-Aubin (France); Arfi-Rouche, Julia [Gustave Roussy, Villejuif (France). Dept. of Radiology; Paris Saclay Univ., Saint-Aubin (France); Michot, Jean-Marie [Gustave Roussy, Villejuif (France). Dept. of Drug Development (DITEP); Paris Saclay Univ., Saint-Aubin (France); Mussot, Sacha; Florea, Valentina [Marie Lannelongue Hospital, Le Plessis Robinson (France). Dept. of Thoracic Surgery; Ghigna, Maria-Rosa [Marie Lannelongue Hospital, Le Plessis Robinson (France). Dept. of Pathology; Dartigues, Peggy [Gustave Roussy, Villejuif (France). Dept. of Pathology; Paris Saclay Univ., Saint-Aubin (France)

2017-11-15

Though commonly used to assess response to therapy, the prognostic value of interim FDG-PET/CT in Primary Mediastinal Large B-cell Lymphoma (PMBCL) is unclear. We conducted a retrospective study on 36 consecutive patients treated at our institution for a PMBCL between 2006 and 2014. All patients with a positive interim FDG-PET/CT had undergone histological restaging consisting either in a surgical debulking of the residual lesion (15 patients) or a CT-guided core needle biopsy (two patients). All FDG-PET/CT were secondarily reviewed according to the more recent Deauville criteria. Interim FDG-PET/CT was considered positive in 17/36 patients using visual evaluation. Among these patients, 14 had a Deauville score of 4. Histological restaging was negative in all but one case, showing inflammation and/or fibrosis. After a median follow-up of 48.5 months, a total of five patients have relapsed, two patients in the positive FDG-PET/CT group, and three patients in the negative FDG-PET/CT group, respectively. These data indicate that a positive interim FDG-PET/CT does not reflect persistence of active disease in the vast majority of PMBCL cases. The relapse rate appears similar regardless of interim FDG-PET/CT results and interpretation criteria. This suggests that interim FDG-PET/CT has a poor positive predictive value, thus kt should be used with caution in PMBCL. (orig.)

Predicting the durability of Portland cement systems in aggressive environments--Laboratory validation

International Nuclear Information System (INIS)

Maltais, Y.; Samson, E.; Marchand, J.

2004-01-01

Portland cement systems are often exposed to severe environments, and their long-term performance is of concern. The main results of a comprehensive investigation of deterioration processes that may affect the behavior of Portland cement systems exposed to chemically aggressive environments is presented. As part of this investigation, well-cured cement paste discs were fully characterized and exposed to deionized water and sodium sulfate solutions. Degradation experiments were conducted under saturated and unsaturated conditions. At the end of the exposure period, microstructural alterations were investigated by microprobe analyses, scanning electron microscope observations and energy-dispersive X-ray analyses. Test results provide information on the basic aspects of various degradation phenomena, such as decalcification and external sulfate attack. Experimental results were also compared with results obtained by a numerical model. The analysis reveals that the intricate microstructural features of the degraded samples could be accurately reproduced by the model

Winter Storm Jupiter of January 2017: Meteorological Drivers, Synoptic Evolution, and Climate Change Considerations in Portland, Oregon

Science.gov (United States)

Dean, S.; Loikith, P. C.

2017-12-01

Although the Pacific Northwest has some of the highest wintertime precipitation in the United States, most urban areas receive little in the way of snow. While 37 inches of wintertime rain fall in Portland on average annually, the city only receives four inches of snow on average. Although wintertime extreme snowstorm events are rare in Portland, in the last century they have occurred about once every ten years. On January 10-12th, 2017, winter storm Jupiter brought 11 inches of snow to downtown Portland within a 12-hour period, making it the largest snowstorm for the city in twenty years. The city declared a state of emergency, over 30,000 citizens lost power, and thousands of businesses were forced to shut down. The anomalously cold air and high amounts of snowfall in a short amount of time made the storm different from others in recent years. This study aims to discover the meteorological drivers behind the January 2017 snowstorm in Portland, Oregon. We also aim to understand how this storm compared with other local storms in the past, and assess the likelihood of a similar event occurring in the future. To do this, reanalysis data were used to display the synoptic evolution of the January 2017 storm. We compared this storm with two other extreme snowfall events from December 2008 and January 1980, assessing meteorological similarities and differences between storms. Results show that the 2017 event was associated with a slow moving, strong low-pressure system accompanied by a 500 hPa trough. These large-scale features helped drive slow moving, locally heavy snow bands over the city of Portland. At the same time, an unusually strong Arctic high-pressure system moved into the interior Pacific Northwest allowing for strong cold air advection west through the Cascade Mountain Range and Columbia River Gorge. Temperature trends show warming of 1-2 °C in the Pacific Northwest since the middle of the last century. Because of this, uncertainty associated with

Interim analysis: A rational approach of decision making in clinical trial.

Science.gov (United States)

Kumar, Amal; Chakraborty, Bhaswat S

2016-01-01

Interim analysis of especially sizeable trials keeps the decision process free of conflict of interest while considering cost, resources, and meaningfulness of the project. Whenever necessary, such interim analysis can also call for potential termination or appropriate modification in sample size, study design, and even an early declaration of success. Given the extraordinary size and complexity today, this rational approach helps to analyze and predict the outcomes of a clinical trial that incorporate what is learned during the course of a study or a clinical development program. Such approach can also fill the gap by directing the resources toward relevant and optimized clinical trials between unmet medical needs and interventions being tested currently rather than fulfilling only business and profit goals.

Interim analysis: A rational approach of decision making in clinical trial

Directory of Open Access Journals (Sweden)

Amal Kumar

2016-01-01

Full Text Available Interim analysis of especially sizeable trials keeps the decision process free of conflict of interest while considering cost, resources, and meaningfulness of the project. Whenever necessary, such interim analysis can also call for potential termination or appropriate modification in sample size, study design, and even an early declaration of success. Given the extraordinary size and complexity today, this rational approach helps to analyze and predict the outcomes of a clinical trial that incorporate what is learned during the course of a study or a clinical development program. Such approach can also fill the gap by directing the resources toward relevant and optimized clinical trials between unmet medical needs and interventions being tested currently rather than fulfilling only business and profit goals.

Resistance to acid attack of portland cement mortars produced with red mud as a pozzolanic additive

International Nuclear Information System (INIS)

Balbino, Thiago Gabriel Ferreira; Fortes, Gustavo Mattos; Lourenco, Rafaela Roberta; Rodrigues, Jose de Anchieta

2011-01-01

Portland cement structures are usually exposed to aggressive environments, which requires the knowledge of the performance of these materials under deleterious conditions. In this study, it was evaluated the resistance to acid attack of mortars that contain ordinary (CPI) and compost (CPII-Z) Portland cements, adding to the first red mud (RB) as a pozzolanic additive in different conditions: without calcination, calcined at 400 ° C and at 600 ° C. The specimens were subjected to HCl and H 2 SO 4 solutions, both with concentration of 1.0 Mol L -1 for 28 days, monitoring the weight loss and leached material nature by atomic emission inductively coupled plasma (ICP). The hydration products were studied by thermogravimetric analysis (TGA) and X-ray diffraction (XRD) of the hydrated cement pastes. It was observed a reduction of portlandite amount in the RB containing cement pastes, indicating a possible pozzolanic activity of the red mud. The mortars prepared with RB were more resistant to HCl, while that ones with calcined RB present a better performance in H 2 SO 4 attack. (author)

Transuranic waste storage and assay facility (TRUSAF) interim safety basis

International Nuclear Information System (INIS)

Gibson, K.D.

1995-09-01

The TRUSAF ISB is based upon current facility configuration and procedures. The purpose of the document is to provide the basis for interim operation or restrictions on interim operations and the authorization basis for the TRUSAF at the Hanford Site. The previous safety analysis document TRUSAF hazards Identification and Evaluation (WHC 1977) is superseded by this document

Retrievable surface storage: interim storage of solidified high-level waste

International Nuclear Information System (INIS)

LaRiviere, J.R.; Nelson, D.C.

1976-01-01

Studies have been conducted on retrievable-surface-storage concepts for the interim storage of solidified high-level wastes. These studies have been reviewed by the Panel on Engineered Storage, convened by the Committee on Radioactive Waste Management of the National Research Council-National Academy of Sciences. The Panel has concluded that ''retrievable surface storage is an acceptable interim stage in a comprehensive system for managing high-level radioactive wastes.'' The scaled storage cask concept, which was recommended by the Panel on Engineered Storage, consists of placing a canister of waste inside a carbon-steel cask, which in turn is placed inside a thick concrete cylinder. The waste is cooled by natural convection air flow through an annulus between the cask and the inner wall of the concrete cylinder. The complete assembly is placed above ground in an outdoor storage area

Commentary: Interim leadership of academic departments at U.S. medical schools.

Science.gov (United States)

Grigsby, R Kevin; Aber, Robert C; Quillen, David A

2009-10-01

Medical schools and teaching hospitals are experiencing more frequent turnover of department chairs. Loss of a department chair creates instability in the department and may have a negative effect on the organization at large. Interim leadership of academic departments is common, and interim chairs are expected to immediately demonstrate skills and leadership abilities. However, little is known about how persons are prepared to assume the interim chair role. Newer competencies for effective leadership include an understanding of the business of medicine, interpersonal and communication skills, the ability to deal with conflict and solve adaptive challenges, and the ability to build and work on teams. Medical schools and teaching hospitals need assistance to meet the unique training and support needs of persons serving as interim leaders. For example, the Association of American Medical Colleges and individual chair societies can develop programs to allow current chairs to reflect on their present positions and plan for the future. Formal leadership training, mentorship opportunities, and conscientious succession planning are good first steps in preparing to meet the needs of academic departments during transitions in leadership. Also, interim leadership experience may be useful as a means for "opening the door" to underrepresented persons, including women, and increasing the diversity of the leadership team.

NESHAP for the Portland Cement Manufacturing Industry: Fact Sheets for Actions Since 2015

Science.gov (United States)

EPA is extending its approval for the use of an alternative method to show compliance with hydrogen chloride (HCl) emissions limits in the National Emission Standards for Hazardous Air Pollutants for the Portland Cement Manufacturing Industry

Incorporation of phosphorus guest ions in the calcium silicate phases of Portland cement from 31P MAS NMR spectroscopy.

Science.gov (United States)

Poulsen, Søren L; Jakobsen, Hans J; Skibsted, Jørgen

2010-06-21

Portland cements may contain small quantities of phosphorus (typically below 0.5 wt % P(2)O(5)), originating from either the raw materials or alternative sources of fuel used to heat the cement kilns. This work reports the first (31)P MAS NMR study of anhydrous and hydrated Portland cements that focuses on the phase and site preferences of the (PO(4))(3-) guest ions in the main clinker phases and hydration products. The observed (31)P chemical shifts (10 to -2 ppm), the (31)P chemical shift anisotropy, and the resemblance of the lineshapes in the (31)P and (29)Si MAS NMR spectra strongly suggest that (PO(4))(3-) units are incorporated in the calcium silicate phases, alite (Ca(3)SiO(5)) and belite (Ca(2)SiO(4)), by substitution for (SiO(4))(4-) tetrahedra. This assignment is further supported by a determination of the spin-lattice relaxation times for (31)P in alite and belite, which exhibit the same ratio as observed for the corresponding (29)Si relaxation times. From simulations of the intensities, observed in inversion-recovery spectra for a white Portland cement, it is deduced that 1.3% and 2.1% of the Si sites in alite and belite, respectively, are replaced by phosphorus. Charge balance may potentially be achieved to some extent by a coupled substitution mechanism where Ca(2+) is replaced by Fe(3+) ions, which may account for the interaction of the (31)P spins with paramagnetic Fe(3+) ions as observed for the ordinary Portland cements. A minor fraction of phosphorus may also be present in the separate phase Ca(3)(PO(4))(2), as indicated by the observation of a narrow resonance at delta((31)P) = 3.0 ppm for two of the studied cements. (31)P{(1)H} CP/MAS NMR spectra following the hydration of a white Portland cement show that the resonances from the hydrous phosphate species fall in the same spectral range as observed for (PO(4))(3-) incorporated in alite. This similarity and the absence of a large (31)P chemical shift ansitropy indicate that the hydrous (PO(4

Comparative evaluation of antimicrobial action of MTA, calcium hydroxide and Portland cement Avaliação comparativa da ação antimicrobiana do MTA, hidróxido de cálcio e cimento Portland

Directory of Open Access Journals (Sweden)

Caroline Sousa Ribeiro

2006-10-01

Full Text Available The present study aimed to evaluate and compare the antimicrobial effect of MTA Dentsply, MTA Angelus, Calcium Hydroxide and Portland cement. Four reference bacterial strains were used: Pseudomonas aeruginosa, Escherichia coli, Bacteroides fragilis, and Enterococcus faecalis. Plates containing Mueller-Hinton agar supplemented with 5% sheep blood, hemin, and menadione were inoculated with the bacterial suspensions. Subsequently, wells were prepared and immediately filled with materials and incubated at 37ºC for 48 hours under anaerobic conditions, except P. aeruginosa. The diameters of inhibition zones were measured, and data analyzed using ANOVA and the Tukey test with 1% level of significance. MTA Dentsply, MTA Angelus and Portland cement inhibited the growth of P. aeruginosa. Calcium Hydroxide was effective against P. aeruginosa and B. fragillis. Under anaerobic conditions, which may hamper the formation of reactive oxygen species, the materials failed to inhibit E. faecalis, and E. coli.O objetivo do presente trabalho foi avaliar e comparar o efeito antimicrobiano do MTA Dentsply, MTA Angelus, hidróxido de cálcio e cimento Portland sobre quatro cepas bacterianas: Pseudomonas aeruginosa, Escherichia coli, Bacteroides fragilis, e Enterococcus faecalis. Placas contendo agar Muller-Hinton suplementadas com 5% de sangue de carneiro, hemina e menadiona foram inoculadas com as suspensões bacterianas. Poços foram confeccionados com auxílio de perfuradores e imediatamente preenchidos com os materiais, e incubados a 37ºC por 48 horas em atmosfera de anaerobiose, exceto P. aeruginosa. O diâmetro dos halos de inibição foi medido e os dados analisados usando o teste estatístico ANOVA e o de Tukey com nível de significância de 1%. O MTA Dentsply, MTA Angelus e Cimento Portland inibiram o crescimento da P.aeruginosa. O hidróxido de cálcio foi efetivo contra P. aeruginosa e B. fragillis. Sob atmosfera de anaerobiose, condição que pode

K basins interim remedial action health and safety plan

Energy Technology Data Exchange (ETDEWEB)

DAY, P.T.

1999-09-14

The K Basins Interim Remedial Action Health and Safety Plan addresses the requirements of the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), as they apply to the CERCLA work that will take place at the K East and K West Basins. The provisions of this plan become effective on the date the US Environmental Protection Agency issues the Record of Decision for the K Basins Interim Remedial Action, currently planned in late August 1999.

Interim safety basis for fuel supply shutdown facility

International Nuclear Information System (INIS)

Brehm, J.R.; Deobald, T.L.; Benecke, M.W.; Remaize, J.A.

1995-01-01

This ISB in conjunction with the new TSRs, will provide the required basis for interim operation or restrictions on interim operations and administrative controls for the Facility until a SAR is prepared in accordance with the new requirements. It is concluded that the risk associated with the current operational mode of the Facility, uranium closure, clean up, and transition activities required for permanent closure, are within Risk Acceptance Guidelines. The Facility is classified as a Moderate Hazard Facility because of the potential for an unmitigated fire associated with the uranium storage buildings

Environmental justice and factors that influence participation in tree planting programs in Portland, Oregon, U.S

Science.gov (United States)

Geoffrey H. Donovan; John Mills

2014-01-01

Many cities have policies encouraging homeowners to plant trees. For these policies to be effective, it is important to understand what motivates a homeowner’s tree-planting decision. Researchers address this question by identifying variables that influence participation in a tree-planting program in Portland, Oregon, U.S. According to the study, homeowners with street...

Elemental atmospheric pollution assessment via moss-based measurements in Portland, Oregon

Science.gov (United States)

Demetrios Gatziolis; Sarah Jovan; Geoffrey Donovan; Michael Amacher; Vicente Monleon

2016-01-01

Mosses accumulate pollutants from the atmosphere and can serve as an inexpensive screening tool for mapping air quality and guiding the placement of monitoring instruments. We measured 22 elements using 346 moss samples collected across Portland, Oregon, in December 2013. Our objectives were to develop citywide maps showing concentrations of each element in moss and...

Trees in the city: valuing street trees in Portland, Oregon

Science.gov (United States)

G.H. Donovan; D.T. Butry

2010-01-01

We use a hedonic price model to simultaneously estimate the effects of street trees on the sales price and the time-on-market (TOM) of houses in Portland. Oregon. On average, street trees add $8,870 to sales price and reduce TOM by 1.7 days. In addition, we found that the benefits of street trees spill over to neighboring houses. Because the provision and maintenance...

Effects of chemical and mineral additives and the water/cement ratio on the thermal resistance of Portland cement concrete

International Nuclear Information System (INIS)

Cesar, Leandro Cesar Dias; Morelli, Arnaldo C.; Baldo, Joao Baptista

1998-01-01

The exposure of Portland concrete to high temperatures (>250 deg C) can damage drastically the microstructural integrity of the material. Since the water/cement ratio as well as the inclusion of superplasticizers and mineral additives (silica fume) can alter constitutively and micro structurally the material, in this work it was investigated per effect of these additions on the damage resistance of portland concrete after exposure to high temperatures. (author)

Recycling of porcelain tile polishing residue in portland cement: hydration efficiency.

Science.gov (United States)

Pelisser, Fernando; Steiner, Luiz Renato; Bernardin, Adriano Michael

2012-02-21

Ceramic tiles are widely used by the construction industry, and the manufacturing process of ceramic tiles generates as a major residue mud derived from the polishing step. This residue is too impure to be reused in the ceramic process and is usually discarded as waste in landfills. But the analysis of the particle size and concentration of silica of this residue shows a potential use in the manufacture of building materials based on portland cement. Tests were conducted on cement pastes and mortars using the addition of 10% and 20% (mass) of the residue. The results of compressive strength in mortars made up to 56 days showed a significant increase in compressive strength greater than 50%. The result of thermogravimetry shows that portlandite is consumed by the cement formed by the silica present in the residue in order to form calcium silicate hydrate and featuring a pozzolanic reaction. This effect improves the performance of cement, contributes to research and application of supplementary cementitious materials, and optimizes the use of portland cement, reducing the environmental impacts of carbon dioxide emissions from its production.

Explicit feedback to enhance the effect of an interim assessment: a cross-over study on learning effect and gender difference

NARCIS (Netherlands)

Olde Bekkink, M.; Donders, R.; van Muijen, G.N.; de Waal, R.M.; Ruiter, D.J.

2012-01-01

In a previous study we demonstrated by a prospective controlled design that an interim assessment during an ongoing small group work (SGW) session resulted in a higher score in the course examination. As this reflects the so-called testing effect, which is supposed to be enhanced by feedback, we

Petrographic Analysis of Portland Cement Concrete Cores from Pease Air National Guard Base, New Hampshire

Science.gov (United States)

2016-11-01

Petrographic Analysis of Portland Cement Concrete Cores from Pease Air National Guard Base, New Hampshire E n g in e e r R e s e a rc h a n d...id, age of the concrete being evaluated and tests performed...4 3 Preface This study was conducted in support of the Air Force Civil Engineer Center (AFCEC) to assess concrete obtained from Pease

Performance Characteristics of Waste Glass Powder Substituting Portland Cement in Mortar Mixtures

Science.gov (United States)

Kara, P.; Csetényi, L. J.; Borosnyói, A.

2016-04-01

In the present work, soda-lime glass cullet (flint, amber, green) and special glass cullet (soda-alkaline earth-silicate glass coming from low pressure mercury-discharge lamp cullet and incandescent light bulb borosilicate glass waste cullet) were ground into fine powders in a laboratory planetary ball mill for 30 minutes. CEM I 42.5N Portland cement was applied in mortar mixtures, substituted with waste glass powder at levels of 20% and 30%. Characterisation and testing of waste glass powders included fineness by laser diffraction particle size analysis, specific surface area by nitrogen adsorption technique, particle density by pycnometry and chemical analysis by X-ray fluorescence spectrophotometry. Compressive strength, early age shrinkage cracking and drying shrinkage tests, heat of hydration of mortars, temperature of hydration, X-ray diffraction analysis and volume stability tests were performed to observe the influence of waste glass powder substitution for Portland cement on physical and engineering properties of mortar mixtures.

Interim Design Report

CERN Document Server

Choubey, S.; Goswami, S.; Berg, J.S.; Fernow, R.; Gallardo, J.C.; Gupta, R.; Kirk, H.; Simos, N.; Souchlas, N.; Ellis, M.; Kyberd, P.; Benedetto, E.; Fernandez-Martinez, E.; Efthymiopoulos, I.; Garoby, R.; Gilardoni, S.; Martini, M.; Prior, G.; Ballett, P.; Pascoli, S.; Bross, A.; Geer, S.; Johnstone, C.; Kopp, J.; Mokhov, N.; Morfin, J.; Neuffer, D.; Parke, S.; Popovic, M.; Strait, J.; Striganov, S.; Blondel, A.; Dufour, F.; Laing, A.; Soler, F.J.P; Lindner, M.; Schwetz, T.; Alekou, A.; Apollonio, M.; Aslaninejad, M.; Bontoiu, C.; Dornan, P.; Eccleston, R.; Kurup, A.; Long, K.; Pasternak, J.; Pozimski, J.; Bogacz, A.; Morozov, V.; Roblin, Y.; Bhattacharya, S.; Majumdar, D.; Mori, Y.; Planche, T.; Zisman, M.; Cline, D.; Stratakis, D.; Ding, X.; Coloma, P.; Donini, A.; Gavela, B.; Lopez Pavon, J.; Maltoni, M.; Bromberg, C.; Bonesini, M.; Hart, T.; Kudenko, Y.; Mondal, N.; Antusch, S.; Blennow, M.; Ota, T.; Abrams, R.J.; Ankenbrandt, C.M.; Beard, K.B.; Cummings, M.A.C.; Flanagan, G.; Johnson, R.P.; Roberts, T.J.; Yoshikawa, C.Y.; Migliozzi, P.; Palladino, V.; de Gouvea, A.; Graves, V.B.; Kuno, Y.; Peltoniemi, J.; Blackmore, V.; Cobb, J.; Witte, H.; Mezzetto, M.; Rigolin, S.; McDonald, K.T.; Coney, L.; Hanson, G.; Snopok, P.; Tortora, L.; Andreopoulos, C.; Bennett, J.R.J.; Brooks, S.; Caretta, O.; Davenne, T.; Densham, C.; Edgecock, R.; Kelliher, D.; Loveridge, P.; McFarland, A.; Machida, S.; Prior, C.; Rees, G.; Rogers, C.; Thomason, J.W.G.; Booth, C.; Skoro, G.; Karadzhov, Y.; Matev, R.; Tsenov, R.; Samulyak, R.; Mishra, S.R.; Petti, R.; Dracos, M.; Yasuda, O.; Agarwalla, S.K.; Cervera-Villanueva, A.; Gomez-Cadenas, J.J.; Hernandez, P.; Li, T.; Martin-Albo, J.; Huber, P.; Back, J.; Barker, G.; Harrison, P.; Meloni, D.; Tang, J.; Winter, W.

2011-01-01

The International Design Study for the Neutrino Factory (the IDS-NF) was established by the community at the ninth "International Workshop on Neutrino Factories, super-beams, and beta- beams" which was held in Okayama in August 2007. The IDS-NF mandate is to deliver the Reference Design Report (RDR) for the facility on the timescale of 2012/13. In addition, the mandate for the study [3] requires an Interim Design Report to be delivered midway through the project as a step on the way to the RDR. This document, the IDR, has two functions: it marks the point in the IDS-NF at which the emphasis turns to the engineering studies required to deliver the RDR and it documents baseline concepts for the accelerator complex, the neutrino detectors, and the instrumentation systems. The IDS-NF is, in essence, a site-independent study. Example sites, CERN, FNAL, and RAL, have been identified to allow site-specific issues to be addressed in the cost analysis that will be presented in the RDR. The choice of example sites shou...

D90: The Strongest Contributor to Setting Time in Mineral Trioxide Aggregate and Portland Cement.

Science.gov (United States)

Ha, William N; Bentz, Dale P; Kahler, Bill; Walsh, Laurence J

2015-07-01

The setting times of commercial mineral trioxide aggregate (MTA) and Portland cements vary. It was hypothesized that much of this variation was caused by differences in particle size distribution. Two gram samples from 11 MTA-type cements were analyzed by laser diffraction to determine their particle size distributions characterized by their percentile equivalent diameters (the 10th percentile, the median, and the 90th percentile [d90], respectively). Setting time data were received from manufacturers who performed indentation setting time tests as specified by the standards relevant to dentistry, ISO 6786 (9 respondents) or ISO 9917.1 (1 respondent), or not divulged to the authors (1 respondent). In a parallel experiment, 6 samples of different size graded Portland cements were produced using the same cement clinker. The measurement of setting time for Portland cement pastes was performed using American Society for Testing and Materials C 191. Cumulative heat release was measured using isothermal calorimetry to assess the reactions occurring during the setting of these pastes. In all experiments, linear correlations were assessed between setting times, heat release, and the 3 particle size parameters. Particle size varied considerably among MTA cements. For MTA cements, d90 was the particle size characteristic showing the highest positive linear correlation with setting time (r = 0.538). For Portland cement, d90 gave an even higher linear correlation for the initial setting time (r = 0.804) and the final setting time (r = 0.873) and exhibited a strong negative linear correlation for cumulative heat release (r = 0.901). Smaller particle sizes result in faster setting times, with d90 (the largest particles) being most closely correlated with the setting times of the samples. Copyright © 2015 American Association of Endodontists. All rights reserved.

Project management plan for Reactor 105-C Interim Safe Storage project

International Nuclear Information System (INIS)

Plagge, H.A.

1996-09-01

Reactor 105-C (located on the Hanford Site in Richland, Washington) will be placed into an interim safe storage condition such that (1) interim inspection can be limited to a 5-year frequency; (2) containment ensures that releases to the environmental are not credible under design basis conditions; and (3) final safe storage configuration shall not preclude or significantly increase the cost for any decommissioning alternatives for the reactor assembly.This project management plan establishes plans, organizational responsibilities, control systems, and procedures for managing the execution of Reactor 105-C interim safe storage activities to meet programmatic requirements within authorized funding and approved schedules

Comparative evaluation of antimicrobial activity of three cements: new endodontic cement (NEC), mineral trioxide aggregate (MTA) and Portland.

Science.gov (United States)

Hasan Zarrabi, Mohammad; Javidi, Maryam; Naderinasab, Mahboube; Gharechahi, Maryam

2009-09-01

Using the agar diffusion method, we conducted an in vitro study to evaluate the antimicrobial activity of mineral trioxide aggregate (MTA), new endodontic cement (NEC) and Portland cement at different concentrations against five different microorganisms. A base layer was made using Muller-Hinton agar for Escherichia coli (ATCC 10538) and Candida (ATCC 10231). For Actinomyces viscosus (ATCC 15987), Enterococcus faecalis (ATCC 10541) and Streptococcus mutans (ATCC 25175) blood agar medium was used. Wells were formed by removing the agar, and the materials were placed in the well immediately after manipulation. The plates were kept at room temperature for 2 h for prediffusion, and then incubated at 37 degrees C for 72 h. The inhibition zones were then measured. The data were analyzed using ANOVA and the Tukey test to compare the differences among the three cements at different concentrations. The positive controls showed bacterial growth, while the negative controls showed no bacterial growth. All materials showed antimicrobial activity against the tested strains except for Enterococcus faecalis. NEC created larger inhibition zones than MTA and Portland cement. This difference was significant for Portland cement (P 0.05). Among the examined microorganisms, the largest inhibition zone was observed for Actinomyces group (P < 0.05). The antimicrobial activity of the materials increased with time and concentration (P < 0.05). It was concluded that NEC is a potent inhibitor of microorganism growth.

Interim FDG-PET Scan in Hodgkin's Lymphoma: Hopes and Caveats

Directory of Open Access Journals (Sweden)

M. André

2011-01-01

Full Text Available FDG-PET has recently emerged as an important tool for the management of Hodgkins lymphoma. Although its use for initial staging and response evaluation at the end of treatment is well established, the place of interim PET for response assessment and subsequent treatment tailoring is still quite controversial. The use of interim PET after a few cycles of chemotherapy may allow treatment reduction for good responders, leading to lesser treatment toxicities as well as early treatment adaptation for bad responders with a potential higher chance for cure. Interpretation of interim PET is a rapidly moving field. Actually, visual interpretation is preferred over quantitative interpretation in this situation. The notion of minimal residual uptake emerged for faint persisting FDG uptake, but has evolved during the recent years. Guidelines using mediastinum and liver as references have been proposed at the expert meeting in Deauville 2009. Actually, several trials are ongoing both for localised and advanced disease to evaluate the FDG-PET potential for early treatment monitoring and tailoring. Until the results of these prospective randomized trials become available, treatment changes according to the interim PET results should remain inappropriate and limited to well-conducted clinical trials.

Rat subcutaneous tissue response to MTA Fillapex® and Portland cement.

Science.gov (United States)

Marques, Nádia Carolina Teixeira; Lourenço Neto, Natalino; Fernandes, Ana Paula; Rodini, Camila de Oliveira; Duarte, Marco Antônio Hungaro; Oliveira, Thais Marchini

2013-01-01

The aim of this study was to evaluate the response of rat subcutaneous tissue to MTA Fillapex® (Angelus), an experimental root canal filling material based on Portland cement and propylene glycol (PCPG), and a zinc oxide, eugenol and iodoform (ZOEI) paste. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Wistar rats for 7 and 15 days. The specimens were stained with hematoxylin and eosin, and evaluated regarding inflammatory reaction parameters by optical microscopy. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated examiners for all experimental periods (kappa=0.96). The histological evaluation showed that all materials caused a moderate inflammatory reaction at 7 days, which subsided with time. A greater inflammatory reaction was observed at 7 days in the tubes filled with ZOEI paste. Tubes filled with MTA Fillapex presented some giant cells, macrophages and lymphocytes after 7 days. At 15 days, the presence of fibroblasts and collagen fibers was observed indicating normal tissue healing. The tubes filled with PCPG showed similar results to those observed in MTA Fillapex. At 15 days, the inflammatory reaction was almost absent at the tissue, with several collagen fibers indicating normal tissue healing. Data were analyzed by the nonparametric Kruskal-Wallis test (α=0.05). Statistically significant difference (p0.05). MTA Fillapex and Portland cement added with propylene glycol had greater tissue compatibility than the PCPG paste.

42 CFR 93.401 - Interaction with other offices and interim actions.

Science.gov (United States)

2010-10-01

... 42 Public Health 1 2010-10-01 2010-10-01 false Interaction with other offices and interim actions. 93.401 Section 93.401 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Human Services General Information § 93.401 Interaction with other offices and interim actions. (a) ORI...

42 CFR 417.572 - Budget and enrollment forecast and interim reports.

Science.gov (United States)

2010-10-01

... 42 Public Health 3 2010-10-01 2010-10-01 false Budget and enrollment forecast and interim reports... PLANS, AND HEALTH CARE PREPAYMENT PLANS Medicare Payment: Cost Basis § 417.572 Budget and enrollment forecast and interim reports. (a) Annual submittal. The HMO or CMP must submit an annual operating budget...

Early interim 18F-FDG PET in Hodgkin's lymphoma: evaluation on 304 patients

International Nuclear Information System (INIS)

Zinzani, Pier Luigi; Stefoni, Vittorio; Broccoli, Alessandro; Argnani, Lisa; Baccarani, Michele; Rigacci, Luigi; Puccini, Benedetta; Castagnoli, Antonio; Vaggelli, Luca; Zanoni, Lucia; Fanti, Stefano

2012-01-01

The use of early (interim) PET restaging during first-line therapy of Hodgkin's lymphoma (HL) in clinical practice has considerably increased because of its ability to provide early recognition of treatment failure allowing patients to be transferred to more intensive treatment regimens. Between June 1997 and June 2009, 304 patients with newly diagnosed HL (147 early stage and 157 advanced stage) were treated with the ABVD regimen at two Italian institutions. Patients underwent PET staging and restaging at baseline, after two cycles of therapy and at the end of the treatment. Of the 304 patients, 53 showed a positive interim PET scan and of these only 13 (24.5%) achieved continuous complete remission (CCR), whereas 251 patients showed a negative PET scan and of these 231 (92%) achieved CCR. Comparison between interim PET-positive and interim PET-negative patients indicated a significant association between PET findings and 9-year progression-free survival and 9-year overall survival, with a median follow-up of 31 months. Among the early-stage patients, 19 had a positive interim PET scan and only 4 (21%) achieved CCR; among the 128 patients with a negative interim PET scan, 122 (97.6%) achieved CCR. Among the advanced-stage patients, 34 showed a persistently positive PET scan with only 9 (26.4%) achieving CCR, whereas 123 showed a negative interim PET scan with 109 (88.6%) achieving CCR. Our results demonstrate the role of an early PET scan as a significant step forward in the management of patients with early-stage or advanced-stage HL. (orig.)

10 CFR 431.401 - Petitions for waiver, and applications for interim waiver, of test procedure.

Science.gov (United States)

2010-01-01

... Renewable Energy, U.S. Department of Energy. Each Application for Interim Waiver must reference the Petition... Renewable Energy. (e) Provisions specific to interim waivers—(1) Disposition of application. If... 10 Energy 3 2010-01-01 2010-01-01 false Petitions for waiver, and applications for interim waiver...

Cytotoxicity of Portland cement with different radiopacifying agents: a cell death study.

Science.gov (United States)

Gomes Cornélio, Ana Lívia; Salles, Loise Pedrosa; Campos da Paz, Mariana; Cirelli, Joni Augusto; Guerreiro-Tanomaru, Juliane Maria; Tanomaru Filho, Mário

2011-02-01

The aim of this study was to investigate the cytotoxicity of white Portland cement (PC) alone or associated with bismuth oxide (PCBi), zirconium oxide (PCZir), and calcium tungstate (PCCa) in 2 cell lineages. Murine periodontal ligament cells (mPDL) and rat osteosarcoma cells (ROS 17/2.8) were exposed for 24 hours to specific concentrations of fresh PC and PC associations with radiopacifiers. Zinc oxide-eugenol cement and hydrogen peroxide treatment were applied as cytotoxic positive controls. Cell viability after incubation with the cements was assessed by mitochondrial dehydrogenase enzymatic assay. Cell morphology was microscopically analyzed by cresyl violet staining, and the mechanism of cell death was determined by acridine orange/ethidium bromide methodology. All data were analyzed statistically by analysis of variance and Tukey post hoc test (P cement elutes. PC alone was not cytotoxic, even at 100 mg/mL. Microscopic images showed that none of the PC formulations caused damage to any cell lines. Statistical analysis of apoptosis/necrosis data demonstrated that PC and PC plus radiopacifying agents promoted significant necrosis cell death only at 100 mg/mL. The mPDL cells were more sensitive than ROS17/2.8. The results showed that PC associated with bismuth oxide, zirconium oxide, or calcium tungstate is not cytotoxic to mPDL or ROS17/2.8. Zirconium oxide and calcium tungstate might be good alternatives as radiopacifying agents. Copyright © 2011 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Portland cement for SO.sub.2 control in coal-fired power plants

Science.gov (United States)

Steinberg, Meyer

1985-01-01

There is described a method of removing oxides of sulfur from the emissions of fossil fuel combustion by injecting portland cement into the boiler with the fuel, the combustion air, or downstream with the combustion gases. There is also described the cement products that result from this method.

Portland cement for SO/sub 2/ control in coal-fired power plants

Science.gov (United States)

Steinberg, M.

1984-10-17

A method is described for removing oxides of sulfur from the emissions of fossil fuel combustion by injecting portland cement into the boiler with the fuel, the combustion air, or downstream with the combustion gases. The cement products that result from this method is also described. 1 tab.

Effect of ProRoot MTA, Portland cement, and amalgam on the expression of fibronectin, collagen I, and TGFβ by human periodontal ligament fibroblasts in vitro.

Science.gov (United States)

Fayazi, Sara; Ostad, Seyed Nasser; Razmi, Hasan

2011-01-01

Today many materials have been introduced for root-end filling materials. One of them is mineral trioxide aggregate (MTA) that is mentioned as a gold standard. The purpose of this in vitro study was to evaluate the reaction of human periodontal ligament fibroblasts to the root-end filling materials, such as ProRoot MTA, Portland cement, and amalgam. Eight impacted teeth were extracted in aseptic condition. The tissues around the roots were used to obtain fibroblast cells. After cell proliferation, they were cultured in the chamber slides and the extracts of the materials were added to the wells. Immunocytochemical method for measuring the expression of Fibronectin, collagen I and transforming growth factor beta (TGF®) was performed by Olysia Bioreport Imaging Software. The results were analyzed by SPSS 13.0 and Tukey post hoc test with PPortland cement group showed the most expression of collagen significantly and after 1 week, Portland cement and MTA groups had the most expression of collagen but there was no significant difference between these 2 groups. After 1 week, the Portland cement group demonstrated a higher amount of TGF® and fibronectin. The results suggest that Portland cement can be used as a less expensive root filling material with low toxicity. It has better effects than amalgam on the fibroblasts.

Estudo para o aproveitamento de resíduos pétreos de marmorarias, como agregados para concreto de cimento Portland

Directory of Open Access Journals (Sweden)

Fábio Conrado de Queiroz

2008-01-01

Full Text Available In this paper, it is presented a study for the utilization of marble shops waste (stone by-products as aggregate of Portland cement concrete. First, the material were separated and classified by lithologic type. After that, they were mixed in a crusher, producing the required aggregates. Several tests for technological characterization of the material were done, intending to evaluate the use of the material as aggregate. Some simulations of Portland cement concrete dosage were done with variation in fine and coarse aggregate composition, water/cement ratio and mortar percentage. The materials were submitted to uniaxial compression test at 7th, 14th and 28th days, showing similar resistances, around to 35 MPa, independent of the aggregate mix and concrete dosage.

A Non-Traditional Interim Project.

Science.gov (United States)

Brown, Diane; Ward, Dorothy

1980-01-01

Describes a project initiated by the Foreign Language Department of Birmingham-Southern College for their Interim term and discusses an interdisciplinary course focusing on Medieval Europe. The course included presentations on German and French language and literature, as well as lectures on the arts, philosophy, and family life of the period.…

Hydration kinetics for the alite, belite, and calcium aluminate phase in Portland cements from 27Al and 29Si MAS NMR spectroscopy

DEFF Research Database (Denmark)

Skibsted, Jørgen; Jensen, Ole Mejlhede; Jakobsen, Hans Jørgen

1997-01-01

29Si magic-angle spinning (MAS) NMR spectroscopy is shown to be a valuable tool for obtaining the quantities of alite and belite in hydrated Portland cements. The hydration (1-180 days) of a white Portland cement with 10 wt.% silica fume added is investigated and the degrees of hydration for alite...

Experimental investigation of the multiple scatter peak of gamma rays in portland cement in the energy range 279-1332 keV

International Nuclear Information System (INIS)

Singh, Tejbir; Singh, Parjit S

2011-01-01

The pulse height spectra for different thicknesses of portland cement in the reflected geometry has been recorded with the help of a NaI(Tl) scintillator detector and 2 K MCA card using different gamma-ray sources such as Hg 203 (279 keV), Cs 137 (662 keV) and Co 60 (1173 and 1332 keV). It has been observed that the multiple scatter peak for portland cement appears at 110 (±7) keV in all the spectra irrespective of different incident photon energies in the range 279-1332 keV from different gamma-ray sources. Further, the variation in the intensity of the multiple scatter peak with the thickness of portland cement in the backward semi-cylinders has been investigated.

XRF analysis of portland cement for major and trace elements

International Nuclear Information System (INIS)

Abdunnabi, A. R.

2012-12-01

Libyan portland cement produced in several factories around the country, in Lip tis, Zoltan, Souq-Elkamis, Dernah and El-Fatach, were analyzed for quantitative major and trace elements and mineral content, which were compered with those imported from Spain, Romania, Cyprus, and Egypt. X-ray fluorescence spectro X lab 2000 spectrometer equipped with Rh-and X-ray tube was used for the analysis of various samples. The detector Si(Li) with a resolution of 148 eV at Mn K-a=5.9 keV facilitates the determination of a wide range of elements from sodium to uranium, with a detection limit at sub levels. Cement samples in the powder form were analyzed using the pellet-technique. The pellets were prepared by mixing 4g of the cement powder with 0.9 g of binder (HWC) and pressed at high pressure. A ful analysis including, background counting, matrix correction and all relevant corrections were achieved automatically by XLAB 2000 software package. For major and trace elements X RF results were higher for most of the elements than those analyzed with atomic absorption spectrometry. The mineral content showed that Libyan cement is comparable to the imported ones, also the Libyan cement meets the requirements of the international specifications of the portland cement. (Author)

Performance of constructed evaporation ponds for disposal of smelter waste water: a case study at Portland Aluminum, Victoria, Australia.

Science.gov (United States)

Salzman, S A; Allinson, G; Stagnitti, F; Coates, M; Hill, R J

2001-06-01

The construction of evaporative ponds and wetlands for the disposal of waste water high in ionic concentrations is a waste disposal strategy currently considered by many industries. However, the design, construction and management of these ponds and wetlands are not straightforward as complex chemical interactions result in both spatial and temporal changes in water quality. The effects of evaporation and drainage on the water quality in two constructed ponds, an adjacent man-made wetland and local groundwater at Portland Aluminium were investigated. The minimum volume of water entering the ponds during the study period was 0.96 +/- 0.16 ML per month. The predicted theoretical evaporative capacity of the two ponds was calculated to be 0.30 +/- 0.07 ML per month. More water enters the ponds than it is theoretically possible to evaporate under the ambient weather conditions at Portland, yet the ponds do not overflow, suggesting percolation through the pond lining. No spatial differences in solute concentrations (fluoride, sulphate, bicarbonate, carbonate, sodium, potassium, calcium, and magnesium ions) were found within the waters of either pond, although temporal differences were apparent. The results support the conclusion that the ponds are not impermeable, and that much of the waste water entering the ponds is being lost through seepage. The impacts on local groundwater chemistry of this seepage are addressed. Significant correlations exist between solute presence within and between the ponds. wetland and groundwater. Fluoride and sulphate concentrations were significantly higher in pond waters throughout the duration of the experiment. Pond sediments revealed a high degree of spatial and temporal heterogeneity in the concentration of all monitored ions resulting from the chemical heterogeneity of the material making up the pond linings. Adsorption isotherms for fluoride indicate that the adsorption capacity of the pond linings remains high for this ion

Determination of coefficient of thermal expansion for Portland Cement Concrete pavements for MEPDG Implementation

Science.gov (United States)

2012-10-01

The Coefficient of Thermal Expansion (CTE) is an important parameter in Portland Cement Concrete (PCC) pavement analysis and design as it is directly proportional to the magnitude of temperature-related pavement deformations throughout the pavement s...

2014 Oregon Department of Geology and Mineral Industries (DOGAMI) Oregon Lidar: Metro Portland, OR

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The dataset encompasses 1221.6 square miles in portions of the greater Portland Metro area in the state of Oregon. The highest hit digital surface models (DSM)...

Interim and final storage casks

International Nuclear Information System (INIS)

Stumpfrock, L.; Kockelmann, H.

2012-01-01

The disposal of radioactive waste is a huge social challenge in Germany and all over the world. As is well known the search for a site for a final repository for high-level waste in Germany is not complete. Therefore, interim storage facilities for radioactive waste were built at plant sites in Germany. The waste is stored in these storage facilities in appropriate storage and transport casks until the transport in a final repository can be carried out. Licensing of the storage and transport casks aimed for use in the public space is done according to the traffic laws and for handling in the storage facility according to nuclear law. Taking into account the activity of the waste to be stored, different containers are in use, so that experience is available from the licensing and operation in interim storage facilities. The large volume of radioactive waste to be disposed of after the shut-down of power generation in nuclear power stations makes it necessary for large quantities of licensed storage and transport casks to be provided soon.

Interim storage report

International Nuclear Information System (INIS)

Rawlins, J.K.

1998-02-01

High-level radioactive waste (HLW) stored at the Idaho Chemical Processing Plant (ICPP) in the form of calcine and liquid and liquid sodium-bearing waste (SBW) will be processed to provide a stable waste form and prepare the waste to be transported to a permanent repository. Because a permanent repository will not be available when the waste is processed, the waste must be stored at ICPP in an Interim Storage Facility (ISF). This report documents consideration of an ISF for each of the waste processing options under consideration

ITER interim design report package documents

International Nuclear Information System (INIS)

1996-01-01

This publication contains the Excerpt from the ITER Council (IC-8), the ITER Interim Design Report, Cost Review and Safety Analysis, ITER Site Requirements and ITER Site Design Assumptions and the Excerpt from the ITER Council (IC-9). 8 figs, 2 tabs

Spent fuel interim storage

International Nuclear Information System (INIS)

Bilegan, Iosif C.

2003-01-01

The official inauguration of the spent fuel interim storage took place on Monday July 28, 2003 at Cernavoda NNP. The inaugural event was attended by local and central public authority representatives, a Canadian Government delegation as well as newsmen from local and central mass media and numerous specialists from Cernavoda NPP compound. Mr Andrei Grigorescu, State Secretary with the Economy and Commerce Ministry, underlined in his talk the importance of this objective for the continuous development of nuclear power in Romania as well as for Romania's complying with the EU practice in this field. Also the excellent collaboration between the Canadian contractor AECL and the Romanian partners Nuclear Montaj, CITON, UTI, General Concret in the accomplishment of this unit at the planned terms and costs. On behalf of Canadian delegation, spoke Minister Don Boudria. He underlined the importance which the Canadian Government affords to the cooperation with Romania aiming at specific objectives in the field of nuclear power such as the Cernavoda NPP Unit 2 and spent fuel interim storage. After traditional cutting of the inaugural ribbon by the two Ministers the festivities continued on the Cernavoda NPP Compound with undersigning the documents regarding the project completion and a press conference

A randomized controlled trial of interim methadone maintenance.

Science.gov (United States)

Schwartz, Robert P; Highfield, David A; Jaffe, Jerome H; Brady, Joseph V; Butler, Carol B; Rouse, Charles O; Callaman, Jason M; O'Grady, Kevin E; Battjes, Robert J

2006-01-01

Effective alternatives to long waiting lists for entry into methadone hydrochloride maintenance treatment are needed to reduce the complications of continuing heroin dependence and to increase methadone treatment entry. To compare the effectiveness of interim methadone maintenance with that of the usual waiting list condition in facilitating methadone treatment entry and reducing heroin and cocaine use and criminal behavior. Randomized, controlled, clinical trial using 2 conditions, with treatment assignment on a 3:2 basis to interim maintenance-waiting list control. A methadone treatment program in Baltimore. A total of 319 individuals meeting the criteria for current heroin dependence and methadone maintenance treatment. Participants were randomly assigned to either interim methadone maintenance, consisting of an individually determined methadone dose and emergency counseling only for up to 120 days, or referral to community-based methadone treatment programs. Entry into comprehensive methadone maintenance therapy at 4 months from baseline; self-reported days of heroin use, cocaine use, and criminal behavior; and number of urine drug test results positive for heroin and cocaine at the follow-up interview conducted at time of entry into comprehensive methadone treatment (or at 4 months from baseline for participants who did not enter regular treatment). Significantly more participants assigned to the interim methadone maintenance condition entered comprehensive methadone maintenance treatment by the 120th day from baseline (75.9%) than those assigned to the waiting list control condition (20.8%) (Pmethadone maintenance results in a substantial increase in the likelihood of entry into comprehensive treatment, and is an effective means of reducing heroin use and criminal behavior among opioid-dependent individuals awaiting entry into a comprehensive methadone treatment program.

Effectiveness of interim stage filter in the exhaust system of glove boxes

International Nuclear Information System (INIS)

Patre, D.K.; Vangara, H.; Thanamani, S.; Gopalakrishnan, R.K.; Mhatre, Amol M.

2018-01-01

All operations in radiochemical laboratories are carried out in containment systems like Glove boxes and Fume hoods. For controlling air contamination two separate air cleaning systems are incorporated. Laboratory has general ventilation system and glove boxes are provided with a negative pressure system (NPS). Glove box exhaust air is passed through three stage filtration systems: in situ, interim and final before discharging to the atmosphere. In addition to the individual HEPA filters of each glove box, there is an interim HEPA filter bank introduced at the laboratory end. This was introduced to reduce a load on main exhaust filter system. Finally the exhaust air is discharged through the final stage HEPA filter located in the filter house through the Stack. The interim HEPA filter bank provides additional protection for the release of particulate activity and reduces load on the final stage filters. In the present work efforts have been put to validate the interim stage filter, which has been introduced, to limit the environmental release

A study of photon interaction in some building materials: High-volume admixture of blast furnace slag into Portland cement

International Nuclear Information System (INIS)

Kurudirek, Murat; Tuerkmen, Ibrahim; Ozdemir, Yueksel

2009-01-01

Total mass attenuation coefficients, mean free paths (MFP), half-value (HVT) and tenth-value (TVT) thicknesses of Portland cement and three mixtures have been calculated in function of the energy from 1 keV to 100 GeV. Both in the low- and high-energy region there were significant variations in those parameters where photoelectric process and pair production partially dominates, respectively. In general, the attenuation parameters were found to vary with chemical composition, density of given material and photon energy.

A study of photon interaction in some building materials: High-volume admixture of blast furnace slag into Portland cement

Energy Technology Data Exchange (ETDEWEB)

Kurudirek, Murat [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey)], E-mail: mkurudirek@gmail.com; Tuerkmen, Ibrahim [Faculty of Engineering, Department of Civil Engineering, Ataturk University, 25240 Erzurum (Turkey); Ozdemir, Yueksel [Faculty of Science, Department of Physics, Ataturk University, 25240 Erzurum (Turkey)

2009-09-15

Total mass attenuation coefficients, mean free paths (MFP), half-value (HVT) and tenth-value (TVT) thicknesses of Portland cement and three mixtures have been calculated in function of the energy from 1 keV to 100 GeV. Both in the low- and high-energy region there were significant variations in those parameters where photoelectric process and pair production partially dominates, respectively. In general, the attenuation parameters were found to vary with chemical composition, density of given material and photon energy.

The influence of shrinkage-cracking on the drying behaviour of White Portland cement using Single-Point Imaging (SPI).

Science.gov (United States)

Beyea, S D; Balcom, B J; Bremner, T W; Prado, P J; Cross, A R; Armstrong, R L; Grattan-Bellew, P E

1998-11-01

The removal of water from pores in hardened cement paste smaller than 50 nm results in cracking of the cement matrix due to the tensile stresses induced by drying shrinkage. Cracks in the matrix fundamentally alter the permeability of the material, and therefore directly affect the drying behaviour. Using Single-Point Imaging (SPI), we obtain one-dimensional moisture profiles of hydrated White Portland cement cylinders as a function of drying time. The drying behaviour of White Portland cement, is distinctly different from the drying behaviour of related concrete materials containing aggregates.

A new aluminium-hydrate species in hydrated Portland cements characterized by 27Al and 29Si MAS NMR spectroscopy

International Nuclear Information System (INIS)

Andersen, Morten Daugaard; Jakobsen, Hans J.; Skibsted, Jorgen

2006-01-01

Recent 27 Al MAS NMR studies of hydrated Portland cements and calcium-silicate-hydrate (C-S-H) phases have shown a resonance from Al in octahedral coordination, which cannot be assigned to the well-known aluminate species in hydrated Portland cements. This resonance, which exhibits the isotropic chemical shift δ iso = 5.0 ppm and the quadrupole product parameter P Q = 1.2 MHz, has been characterized in detail by 27 Al MAS and 27 Al{ 1 H} CP/MAS NMR for different hydrated white Portland cements and C-S-H phases. These experiments demonstrate that the resonance originates from an amorphous or disordered aluminate hydrate which contains Al(OH) 6 3- or O x Al(OH) 6-x (3+x)- units. The formation of the new aluminate hydrate is related to the formation of C-S-H at ambient temperatures, however, it decomposes by thermal treatment at temperatures of 70-90 o C. From the experiments in this work it is proposed that the new aluminate hydrate is either an amorphous/disordered aluminate hydroxide or a calcium aluminate hydrate, produced as a separate phase or as a nanostructured surface precipitate on the C-S-H phase. Finally, the possibilities of Al 3+ for Ca 2+ substitution in the principal layers and interlayers of the C-S-H structure are discussed

The effect of urban trees on the rental price of single-family homes in Portland, Oregon

Science.gov (United States)

Geoffrey H. Donovan; David T. Butry

2011-01-01

Few studies have estimated the effect of environmental amenities on the rental price of houses. We address this gap in the literature by quantifying the effect of urban trees on the rental price of single-family homes in Portland, Oregon, USA. We found that an additional tree on a house's lot increased monthly rent by $5.62, and a tree in the public right of way...

Interim reliability evaluation program (IREP)

International Nuclear Information System (INIS)

Carlson, D.D.; Murphy, J.A.

1981-01-01

The Interim Reliability Evaluation Program (IREP), sponsored by the Office of Nuclear Regulatory Research of the US Nuclear Regulatory Commission, is currently applying probabilistic risk analysis techniques to two PWR and two BWR type power plants. Emphasis was placed on the systems analysis portion of the risk assessment, as opposed to accident phenomenology or consequence analysis, since the identification of risk significant plant features was of primary interest. Traditional event tree/fault tree modeling was used for the analysis. However, the study involved a more thorough investigation of transient initiators and of support system faults than studies in the past and substantially improved techniques were used to quantify accident sequence frequencies. This study also attempted to quantify the potential for operator recovery actions in the course of each significant accident

LANDFILL BIOREACTOR PERFORMANCE, SECOND INTERIM REPORT

Science.gov (United States)

A bioreactor landfill is a landfill that is operated in a manner that is expected to increase the rate and extent of waste decomposition, gas generation, and settlement compared to a traditional landfill. This Second Interim Report was prepared to provide an interpretation of fie...

DOE UST interim subsurface barrier technologies workshop

International Nuclear Information System (INIS)

1992-09-01

This document contains information which was presented at a workshop regarding interim subsurface barrier technologies that could be used for underground storage tanks, particularly the tank 241-C-106 at the Hanford Reservation

Ordinary Portland Cement matrix for solidification of cellulosic protective clothes hazardous wastes

International Nuclear Information System (INIS)

Shatta, H.A.; Saleh, H.M.

2006-01-01

The used cellulosic protective clothes constitutes considerable fraction of the hazardous and radioactive wastes accumulated during the practical daily life. The direct solidification of these wastes with ordinary Portland cement resulted in waste forms having undesired characters, therefore, it is recommended to immobilize the secondary waste solutions coming from the oxidative degradation of the used protective clothes waste simulates rather than direct imbedding. IR analyses, X-ray diffraction and thermal characteristics for products of both direct encapsulation of the waste and the cementation of its degradation products were performed to evaluate the properties of the final waste cemented form before their disposal. Based on the results reached from X-ray diffraction, IR spectrograms and thermal analyses reports, it could be stated that no detectable changes in hydration and curing coarse of ordinary Portland cement when mixing the residual secondary waste solution resulting from the oxidative degradation of the used protective clothes waste simulate compared with mixing cement with water and in reverse with imbedding the unprocessed waste in cement matrix

Bioactive coatings on Portland cement substrates: Surface precipitation of apatite-like crystals

International Nuclear Information System (INIS)

Gallego, Daniel; Higuita, Natalia; Garcia, Felipe; Ferrell, Nicholas; Hansford, Derek J.

2008-01-01

We report a method for depositing bioactive coatings onto cement materials for bone tissue engineering applications. White Portland cement substrates were hydrated under a 20% CO 2 atmosphere, allowing the formation of CaCO 3 . The substrates were incubated in a calcium phosphate solution for 1, 3, and 6 days (CPI, CPII, and CPIII respectively) at 37 deg. C to induce the formation of carbonated apatite. Cement controls were prepared and hydrated with and without CO 2 atmosphere (C+ and C- respectively). The presence of apatite-like crystals was verified by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The substrate cytocompatibility was evaluated via SEM after 24 hour cell cultures. SEM revealed the presence Ca(OH) 2 on C-, and CaCO 3 on C+. Apatite-like crystals were detected only on CPIII, confirmed by phosphorus EDS peaks only for CPIII. Cells attached and proliferated similarly well on all the substrates except C-. These results prove the feasibility of obtaining biocompatible and bioactive coatings on Portland cement for bone tissue engineering applications

Portland cement with additives in the repair of furcation perforations in dogs.

Science.gov (United States)

Silva Neto, José Dias da; Schnaider, Taylor Brandão; Gragnani, Alfredo; Paiva, Anderson Paulo de; Novo, Neil Ferreira; Ferreira, Lydia Masako

2012-11-01

To evaluate the use of Portland cements with additives as furcation perforation repair materials and assess their biocompatibility. The four maxillary and mandibular premolars of ten male mongrel dogs (1-1.5 years old, weighing 10-15 kg) received endodontic treatment (n=80 teeth). The furcations were perforated with a round diamond bur (1016 HL). The perforations involved the dentin, cementum, periodontal ligament, and alveolar bone. A calcium sulfate barrier was placed into the perforated bone to prevent extrusion of obturation material into the periradicular space. The obturation materials MTA (control), white, Type II, and Type V Portland cements were randomly allocated to the teeth. Treated teeth were restored with composite resin. After 120 days, the animals were sacrificed and samples containing the teeth were collected and prepared for histological analysis. There were no significant differences in the amount of newly formed bone between teeth treated with the different obturation materials (p=0.879). Biomineralization occurred for all obturation materials tested, suggesting that these materials have similar biocompatibility.

Effect of wastewater on properties of Portland pozzolana cement

Science.gov (United States)

Babu, G. Reddy

2017-07-01

This paper presents the effect of wastewaters on properties of Portland pozzolana cement (PPC). Fourteen water treatment plants were found out in the Narasaraopet municipality region in Guntur district, Andhra Pradesh, India. Approximately, from each plant, between 3500 and 4000 L/day of potable water is selling to consumers. All plants are extracting ground water and treating through Reverse Osmosis (RO) process. During water treatment, plants are discharging approximately 1,00,000 L/day as wastewater in side drains in Narasaraopet municipality. Physical and chemical analysis was carried out on fourteen plants wastewater and distilled water as per producer described in APHA. In the present work, based on the concentrations of constituent's in wastewater, four typical plants i.e., Narasaraopeta Engineering College (NECWW), Patan Khasim Charitable Trust (PKTWW), Mahmadh Khasim Charitable Trust (MKTWW) and Amara (ARWW) were considered. The performance of four plants wastewater on physical properties i.e., setting times, compressive strength, and flexural strength of Portland pozzolana Cement (PPC) were performed in laboratories and compared same with reference specimens i.e., made with Distilled Water (DW) as mixing water. No significant change was observed in initial and finial setting time but setting times of selected wastewaters were retarded as compared to that of reference water. Almost, no change was observed in 90 days compressive and flexural strengths in four plants wastewaters specimens compared to that of reference water specimens. XRD technique was employed to find out main hydration compounds formed in the process.

A conservative method of retaining an interim obturator for a total maxillectomy patient

Directory of Open Access Journals (Sweden)

Nirmal Famila Bettie

2017-01-01

Full Text Available Interim obturators are indicated during the postsurgical phases. It promotes surgical healing and serves as a temporary prosthesis to rehabilitate a patient with intra-oral surgical defect. Retention is gained by wiring, surgical suturing, and other noninvasive methods to enable functional rehabilitation and easy replacement with a permanent obturator. Interim obturators serve as an easy guide for replacing with definitive obturators by indicating prosthesis extensions and the required method of retention. A more conservative and noninvasive method of retaining an interim obturator for a maxillectomy patient is described in this case report.

A Conservative Method of Retaining an Interim Obturator for a Total Maxillectomy Patient.

Science.gov (United States)

Bettie, Nirmal Famila

2017-11-01

Interim obturators are indicated during the postsurgical phases. It promotes surgical healing and serves as a temporary prosthesis to rehabilitate a patient with intra-oral surgical defect. Retention is gained by wiring, surgical suturing, and other noninvasive methods to enable functional rehabilitation and easy replacement with a permanent obturator. Interim obturators serve as an easy guide for replacing with definitive obturators by indicating prosthesis extensions and the required method of retention. A more conservative and noninvasive method of retaining an interim obturator for a maxillectomy patient is described in this case report.

Effect of blastfurnace slag addition to Portland cement for cationic exchange resins encapsulation

Directory of Open Access Journals (Sweden)

Stefan L.

2013-07-01

Full Text Available In the nuclear industry, cement-based materials are extensively used to encapsulate spent ion exchange resins (IERs before their final disposal in a repository. It is well known that the cement has to be carefully selected to prevent any deleterious expansion of the solidified waste form, but the reasons for this possible expansion are not clearly established. This work aims at filling the gap. The swelling pressure of IERs is first investigated as a function of ions exchange and ionic strength. It is shown that pressures of a few tenths of MPa can be produced by decreases in the ionic strength of the bulk solution, or by ion exchanges (2Na+ instead of Ca2+, Na+ instead of K+. Then, the chemical evolution of cationic resins initially in the Na+ form is characterized in CEM I (Portland cement and CEM III (Portland cement + blastfurnace slag cements at early age and an explanation is proposed for the better stability of CEM III material.

Determination of the Apical Sealing Abilities of Mineral Trioxide Aggregate, Portland Cement, and Bioaggregate After Irrigation with Different Solutions.

Science.gov (United States)

Bayram, H Melike; Saklar, Feridun; Bayram, Emre; Orucoglu, Hasan; Bozkurt, Alperen

2015-06-01

The purpose of this study was to investigate the sealing ability of root-end filling materials such as mineral trioxide aggregate (MTA), Portland cement, and bioaggregate (BA) after irrigation with different solutions. We examined 130 human maxillar central teeth. After cutting the teeth at the cementoenamel junction, the root canals were expanded using nickel-titanium rotary instruments. Root canals were filled with AH-plus and gutta-percha. Then, the roots were cut apically, and 3 mm deep retrograde cavities were prepared. The roots were divided 12 experimental groups, consisting 10 teeth each; the positive and negative control groups contained five teeth each. The retrograde cavities were rinsed using ethylenediaminetetraacetic acid (EDTA), chlorhexidine (CHX), BioPure(™) mixture of a tetracycline isomer, an acid, and a detergent (MTAD), or distilled water. Next, groups 1, 2, 3, and 4 were sealed with MTA; groups 5, 6, 7, and 8 were sealed with Portland cement; and groups 9, 10, 11, and 12 were sealed with BA. Then, apical microleakage was evaluated by using a computerized fluid filtration method. The results of the leakage test were statistically evaluated by the post-hoc Tukey's test. MTA, Portland cement, and BA root-end filling materials showed the least leakage in the CHX and distilled water groups. The highest leakage was observed in the EDTA and MTAD groups. The sealing ability of BA was as good as that of MTA. EDTA and MTAD increased the apical leakage and CHX and distilled water decreased the leakage of the root-end filling materials examined in this study.

78 FR 41125 - Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting

Science.gov (United States)

2013-07-09

... NUCLEAR REGULATORY COMMISSION [NRC-2013-0114] Interim Enforcement Policy for Permanent Implant Brachytherapy Medical Event Reporting AGENCY: Nuclear Regulatory Commission. ACTION: Policy statement; revision. SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing an interim Enforcement Policy that allows...

Technical study of a thermally dense long term interim storage facility

International Nuclear Information System (INIS)

Le Duigou, A.; Badie, M.; Duret, B.; Bricard, A.

2001-01-01

The COFRE concept is aimed at the surface and thermal densification of the interim storage facility for irradiated fuels. The facility provides the biological shielding. A conditioning cell is used to load and retrieve the fuel assemblies. The facility container is the second containment barrier. The high power levels are managed by an auxiliary cooling system whose original feature is the passive use of a water evaporation-condensation cycle in a sealed circuit. The removable evaporator abuts the container. The air cooled condenser is placed outside the facility. Contact resistance and heat pipe mode were successfully modelled and are undergoing experimental validation on the THERESE and REBECA loops. (author)

A clear-sky hyperspectral closure study for MERRA-2 and ERA-interim reanalyses

Science.gov (United States)

Chen, X.; Huang, X.; Loeb, N. G.; Dong, X.; Xi, B.; Dolinar, E. K.; Bosilovich, M. G.; Kato, S.; Smith, W. L., Jr.; Stackhouse, P. W., Jr.

2017-12-01

We carried out a clear-sky radiance closure study to compare four sets of synthetic AIRS spectra to 51 AIRS L1 spectra over the ARM Southern Great Plains (SGP) site. The AIRS observations were made when the ARM SGP cloud radar identified cloud free situation for 50-km region within the SGP site. Four sets of synthetic AIRS spectra are calculated using collocated atmospheric profiles from ARM SGP sounding, AIRS L2 retrievals, MERRA-2 and ECMWF ERA-Interim reanalyses. Only channels that are sensitive to temperature, CO2 and water vapor and not to other trace gases are selected for study. The selected channels are further divided into different groups according to their sensitivities to the emission from different vertical levels and to H2O and CO2, respectively. Observed and synthetic radiances of each group are then examined. For synthetic spectra using the AIRS L2 retrievals or the ARM SGP sounding profiles, the brightness temperature (BT) differences between synthetic and observed ones are within ±0.5 K or even smaller, for all groups and for all four seasons. For MERRA-2 and ECMWF-interim reanalyses, the BT differences from observations for each CO2 group are generally within ±0.5 K, indicating good agreements with respect to temperature profiles in the reanalyses. The BT differences for H2O groups are all negative, ranging from -0.5K to -1.5K. The largest BT difference is -1.5K for H2O channels peaking at 400-200 hPa. Such BT difference is persistent when the synthetic radiances based on reanalyses are compared with observed ones for the entire zone of 30°N-40°N. These comparisons imply that the reanalyses can represent the temperature profile well but there is persistent wet bias in the reanalyses, especially for the upper troposphere. The water vapor at 400-200 hPa in reanalyses needs to be adjusted by about -0.01 g/kg in order to reach agreement with the observed radiances.

Pathways to deep decarbonization - Interim 2014 Report

International Nuclear Information System (INIS)

2014-01-01

The interim 2014 report by the Deep Decarbonization Pathways Project (DDPP), coordinated and published by IDDRI and the Sustainable Development Solutions Network (SDSN), presents preliminary findings of the pathways developed by the DDPP Country Research Teams with the objective of achieving emission reductions consistent with limiting global warming to less than 2 deg. C. The DDPP is a knowledge network comprising 15 Country Research Teams and several Partner Organizations who develop and share methods, assumptions, and findings related to deep decarbonization. Each DDPP Country Research Team has developed an illustrative road-map for the transition to a low-carbon economy, with the intent of taking into account national socio-economic conditions, development aspirations, infrastructure stocks, resource endowments, and other relevant factors. The interim 2014 report focuses on technically feasible pathways to deep decarbonization

Characterization and chemical activity of Portland cement and two experimental cements with potential for use in dentistry.

Science.gov (United States)

Camilleri, J

2008-09-01

To evaluate the chemical activity of Portland cement and two other cement types with similar chemical composition to mineral trioxide aggregate with the aim of developing these cements for further applications in dentistry. The chemical composition of the three cement types namely Portland cement, calcium sulpho-aluminate cement and calcium fluoro-aluminate cement was evaluated by elemental analysis using energy dispersive analysis with X-ray under the scanning electron microscope and by X-ray diffraction analysis (XRD) to determine the phases. The constituents of the hydration reaction by-products were evaluated by XRD analysis of the set cements at 1, 7, 28 and 56 days and by analysis of the leachate by ion chromatography. The pH of both cements and leachate was determined at different time intervals. Cements admixed with micro-silica were also tested to determine the effect of micro-silica on the reaction by-products. All three cement types were composed of tricalcium silicate as the main constituent phase. The hydration reaction of Portland cement produced calcium hydroxide. However, this was not present in the other cements tested at all ages. Admixed micro-silica had little or no effect on the cements with regard to reaction by-products. The pH of all cements tested was alkaline. Both the experimental calcium sulpho-aluminate cement and calcium fluoro-aluminate cement had different hydration reactions to that of Portland cement even though calcium silicate was the major constituent element of both cement types. No calcium hydroxide was produced as a by-product to cement hydration. Micro-silica addition to the cement had no effect on the hydration reaction.

The impact of zirconium oxide radiopacifier on the early hydration behaviour of white Portland cement.

Science.gov (United States)

Coleman, Nichola J; Li, Qiu

2013-01-01

Zirconium oxide has been identified as a candidate radiopacifying agent for use in Portland cement-based biomaterials. During this study, the impact of 20 wt.% zirconium oxide on the hydration and setting reactions of white Portland cement (WPC) was monitored by powder X-ray diffraction (XRD), (29)Si and (27)Al magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR), transmission electron microscopy (TEM) and Vicat apparatus. The presence of 20 wt.% zirconium oxide particles in the size-range of 0.2 to 5 μm was found to reduce the initial and final setting times of WPC from 172 to 147 min and 213 to 191 min, respectively. Zirconium oxide did not formally participate in the chemical reactions of the hydrating cement; however, the surface of the zirconium oxide particles presented heterogeneous nucleation sites for the precipitation and growth of the early C-S-H gel products which accelerated the initial setting reactions. The presence of zirconium oxide was found to have little impact on the development of the calcium (sulpho)aluminate hydrate phases. Copyright © 2012 Elsevier B.V. All rights reserved.

33 CFR 385.38 - Interim goals.

Science.gov (United States)

2010-07-01

..., monitoring and assessment; (ii) Be provided to the independent scientific review panel established in.... The interim goals shall be developed through the use of appropriate models and tools and shall provide... to be required to meet long-term hydrological and ecological restoration goals, based on best...

Interim guidelines for protecting fire-fighting personnel from multiple hazards at nuclear plant sites

International Nuclear Information System (INIS)

Klein, A.R.; Bloom, C.W.

1989-07-01

This report provides interim guidelines for reducing the impact to fire fighting and other supporting emergency response personnel from the multiple hazards of radiation, heat stress, and trauma when fighting a fire in a United States commercial nuclear power plant. Interim guidelines are provided for fire brigade composition, training, equipment, procedures, strategies, heat stress and trauma. In addition, task definitions are provided to evaluate and further enhance the interim guidelines over the long term. 19 refs

Urban Flooding Analysis Using Radar Rainfall Data and 2-D Hydrodynamic Model: A Pilot Study of Back Cover Area, Portland, Maine

Energy Technology Data Exchange (ETDEWEB)

Yan, Eugene [Argonne National Lab. (ANL), Argonne, IL (United States); Pierce, Julia [Argonne National Lab. (ANL), Argonne, IL (United States); Mahat, Vinod [Argonne National Lab. (ANL), Argonne, IL (United States); Jared, Alissa [Argonne National Lab. (ANL), Argonne, IL (United States); Collis, Scott [Argonne National Lab. (ANL), Argonne, IL (United States); Verner, Duane [Argonne National Lab. (ANL), Argonne, IL (United States); Wall, Thomas [Argonne National Lab. (ANL), Argonne, IL (United States)

2016-11-01

This project is a part of the Regional Resiliency Assessment Program, led by the Department of Homeland Security, to address flooding hazards of regional significance for Portland, Maine. The pilot study was performed by Argonne National Laboratory to identify differences in spatial rainfall distributions between the radar-derived and rain-gauge rainfall datasets and to evaluate their impacts on urban flooding. The flooding impact analysis utilized a high-resolution 2-dimensional (2-D) hydrodynamic model (15 ft by 15 ft) incorporating the buildings, streets, stream channels, hydraulic structures, an existing city storm drain system, and assuming a storm surge along the coast coincident with a heavy rainfall event. Two historical storm events from April 16, 2007, and September 29, 2015, were selected for evaluation. The radar-derived rainfall data at a 200-m resolution provide spatially-varied rainfall patterns with a wide range of intensities for each event. The resultant maximum flood depth using data from a single rain gauge within the study area could be off (either under- or over-estimated) by more than 10% in the 2007 storm and more than 60% in the 2015 storm compared to the radar-derived rainfall data. The model results also suggest that the inundation area with a flow depth at or greater than 0.5 ft could reach 11% (2007 storm) and 17% (2015 storm) of the total study area, respectively. The lowland areas within the neighborhoods of North Deering, East Deering, East and West Baysides and northeastern Parkside, appear to be more vulnerable to the flood hazard in both storm events. The high-resolution 2-D hydrodynamic model with high-resolution radar-derived rainfall data provides an excellent tool for detailed urban flood analysis and vulnerability assessment. The model developed in this study could be potentially used to evaluate any proposed mitigation measures and optimize their effects in the future for Portland, ME.

Effect of saliva and blood contamination on the bi-axial flexural strength and setting time of two calcium-silicate based cements: Portland cement and biodentine.

Science.gov (United States)

Alhodiry, W; Lyons, M F; Chadwick, R G

2014-03-01

This study evaluated the effect of contamination with saliva and blood on the bi-axial flexural strength and setting time of pure gray Portland cement and Biodentine (Septodont, Allington, UK). A one-way ANOVA showed that contamination caused no significant difference between the cements in bi-axial flexural strength (P> 0.05). However there was a significant difference in setting time (PPortland cement taking longer than Biodentine, regardless of the contaminant, and contamination with blood increased the setting time of both materials. Biodentine was similar in strength to Portland cement, but had a shorter setting time for both contaminated and non-contaminated samples.

Interim format and content for a physical security plan for nuclear power plants

International Nuclear Information System (INIS)

1977-02-01

The document serves as interim guidance to assist the licensee or applicant in the preparation of a physical security plan. It is to be used in conjunction with interim acceptance criteria for physical security programs, which will be distributed at a later date

ASPECTS CONCERNING INTERIM FINANCIAL REPORTING IN ROMANIA: STANDARDS AND REGULATIONS

Directory of Open Access Journals (Sweden)

Aristita Rotila

2014-12-01

Full Text Available The mechanisms employed for the communication of accounting information that is necessary for users in their economic decision-making process consist of the financial statements of an entity. All legal entities, no matter the domain of their activity, have the obligation to draw up annual financial statements for every completed financial year. For certain categories of entities, reporting obligations are also required for periods other than the annual reporting, throughout the financial year. It is the case of interim financial reporting. At the level of the international accounting framework, the aspects related to interim financial reporting are the subject of a separate standard, namely, IAS 34 Interim Financial Reporting. In Romania, the current system of accounting regulations concerning the annual financial statements comprises accounting regulations that comply with the European directives and which apply to the various categories of entities, on the one hand and, on the other, accounting regulations in line with the IFRS, which are applicable to other classes of entities from certain activity sectors. The accounting regulations that apply to each category refer to, among other things, the contents and the format of financial statements that have to be presented. Analysing the system of norms and regulations, this article identifies the requirements concerning interim financial reporting in Romania, with reference to the different types of entities.

Clinical and computed tomographic evaluation of portland cement pulpotomy in primary molar: A case report

Directory of Open Access Journals (Sweden)

Kamrun Nahar

2016-08-01

Full Text Available The present case describes the clinical & radiographic outcome of a Portland Cement pulpotomy. The 5 years old girl presenting extensive carious exposure in her mandibular left 2nd deciduous molar and was suffering pain in her left lower jaw only on exposure to cold for last 2 days. She was ultimately diagnosed clinic-radio-graphically as a case of irreversible pulpitis. Coronal pulpotomy procedure was carried out in the responsible tooth and Portland cement (PC was applied as a medicament after pulpotomy. At the 3 & 6-months follow-up appointments, treated tooth was asymptomatic clinically and radiographic examinations revealed no sign of periradicular pathosis in the pulpotomized teeth. Additionally, the formation of a dentin bridge immediately below the PC in the treated tooth was confirmed by RVG and CBCT.

Taking interim actions: Integrating CERCLA and NEPA to move ahead with site cleanup

International Nuclear Information System (INIS)

MacDonell, M.M.; Peterson, J.M.; Valett, G.L.; McCracken, S.H.

1991-01-01

The cleanup of contaminated sites can be expedited by using interim response actions in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). In fact, a major portion of some Superfund sites can be cleaned up using interim actions. For CERCLA sites being remediated by the US Department of Energy (DOE), such actions must also comply with the National Environmental Policy Act (NEPA) because the DOE has established a policy for integrating CERCLA and NEPA requirements. A strategy for the integrated documentation with implementation of interim actions has been applied successfully at the Weldon Spring site, and major cleanup projects are currently underway. This paper discusses some of the issues associated with integrating CERCLA and NEPA for interim actions and summarizes those actions that have been identified for the Weldon Spring site

Taking interim actions: Integrating CERCLA and NEPA to move ahead with site cleanup

International Nuclear Information System (INIS)

MacDonell, M.M.; Peterson, J.M.; Valett, G.L.; McCracken, S.H.

1991-01-01

The cleanup of contaminated sites can be expedited by using interim response actions in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended, and the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). In fact, a major portion of some Superfund sites can be cleaned up using interim actions. For CERCLA sites being remediated by the US Department of Energy (DOE), such actions must also comply with the National Environmental Policy Act (NEPA) because the DOE has established a policy for integrating CERCLA and NEPA requirements. A strategy for the integrated documentation and implementation of interim actions has been applied successfully at the Weldon Spring site, and major cleanup projects are currently underway. This paper discusses some of the issues associated with integrating CERCLA and NEPA for interim actions and summarizes those actions that have been identified for the Weldon Spring site

Influence of Ba2+ and Sr2+ ions on the hydration process of portland cement and blended cements

Directory of Open Access Journals (Sweden)

Živanović, B. M.

1987-12-01

Full Text Available This study concerns the influence of the concentration of Sr2+ and Ba2+ ions in mortar batch waters upon the hydration process of various Portland and additive cements. An increase in the mechanical resistence of said cements is observed, after 28 days, when the concentration of Ba2+ and Sr2+ ions in the mortar batch waters increases. This suggests a possible microstructural explanation of said phenomenon.En el presente trabajo se estudia la influencia de la concentración de los iones Sr2+ y Ba2+ en las aguas de amasado sobre el proceso de hidratación de varios cementos portland y de adición. Se comprueba un incremento de las resistencias mecánicas de dichos cementos, a los 28 días, cuando aumenta la concentración de los iones Ba2+ y Sr2+ en las aguas de amasado, lo cual sugiere una posible explicación microestructural a dicho fenómeno.

19 CFR 354.8 - Interim sanctions.

Science.gov (United States)

2010-04-01

... reconsider imposition of interim sanctions on the basis of new and material evidence or other good cause... Secretary may petition a presiding official to impose such sanctions. (b) The presiding official may impose... person to return material previously provided by the Department and all other materials containing the...

Clinical and Radiographic Evaluation of the Effectiveness of Formocresol, Mineral Trioxide Aggregate, Portland Cement, and Enamel Matrix Derivative in Primary Teeth Pulpotomies: A Two Year Follow-Up.

Science.gov (United States)

Yildirim, Ceren; Basak, Feridun; Akgun, Ozlem Marti; Polat, Gunseli Guven; Altun, Ceyhan

2016-01-01

The aim of this study was to evaluate and to compare clinical and radiographic outcomes of 4 materials (formocresol, mineral trioxide aggregate (MTA), Portland cement and enamel matrix derivative) using in primary teeth pulpotomies. Sixty-five patients aged 5-9 years (32 female, 33 male) were included in this study. A total of 140 primary first and second molars with deep caries were treated with pulpotomy. All teeth were then restored with stainless steel crowns. The treated teeth were evaluated clinically and radiographically at 3, 6, 12, 18 and 24 months. At 24 months, the clinical success rates of formocresol, MTA, Portland cement, and enamel matrix derivative were 96.9%, 100%, 93.9%, and 93.3%, respectively. The corresponding radiographic success rates were 84.4%, 93.9%, 86.7% and 78.1%, respectively. Although there were no statistically significant differences in clinical and radiographic success rates among the 4 groups, MTA appears to be superior to formocresol, Portland cement, and enamel matrix derivative as a pulpotomy agent in primary teeth.

Next Generation Melter Optioneering Study - Interim Report

International Nuclear Information System (INIS)

Gray, M.F.; Calmus, R.B.; Ramsey, G.; Lomax, J.; Allen, H.

2010-01-01

The next generation melter (NOM) development program includes a down selection process to aid in determining the recommended vitrification technology to implement into the WTP at the first melter change-out which is scheduled for 2025. This optioneering study presents a structured value engineering process to establish and assess evaluation criteria that will be incorporated into the down selection process. This process establishes an evaluation framework that will be used progressively throughout the NGM program, and as such this interim report will be updated on a regular basis. The workshop objectives were achieved. In particular: (1) Consensus was reached with stakeholders and technology providers represented at the workshop regarding the need for a decision making process and the application of the D 2 0 process to NGM option evaluation. (2) A framework was established for applying the decision making process to technology development and evaluation between 2010 and 2013. (3) The criteria for the initial evaluation in 2011 were refined and agreed with stakeholders and technology providers. (4) The technology providers have the guidance required to produce data/information to support the next phase of the evaluation process. In some cases it may be necessary to reflect the data/information requirements and overall approach to the evaluation of technology options against specific criteria within updated Statements of Work for 2010-2011. Access to the WTP engineering data has been identified as being very important for option development and evaluation due to the interface issues for the NGM and surrounding plant. WRPS efforts are ongoing to establish precisely data that is required and how to resolve this Issue. It is intended to apply a similarly structured decision making process to the development and evaluation of LAW NGM options.

Compilation of interim technical research memoranda. Volume I

International Nuclear Information System (INIS)

Shanahan, W.R.

1984-04-01

Four interim technical research memoranda are presented that describe the results of numerical simulations designed to investigate the dynamics of energetic plasma beams propagating across magnetic fields

Solidification of ion exchange resins saturated with Na+ ions: Comparison of matrices based on Portland and blast furnace slag cement

International Nuclear Information System (INIS)

Lafond, E.; Cau dit Coumes, C.; Gauffinet, S.; Chartier, D.; Stefan, L.; Le Bescop, P.

2017-01-01

This work is devoted to the conditioning of ion exchange resins used to decontaminate radioactive effluents. Calcium silicate cements may have a good potential to encapsulate spent resins. However, certain combinations of cement and resins produce a strong expansion of the final product, possibly leading to its full disintegration. The focus is placed on the understanding of the behaviour of cationic resins in the Na + form in Portland or blast furnace slag (CEM III/C) cement pastes. During hydration of the Portland cement paste, the pore solution exhibits a decrease in its osmotic pressure, which causes a transient expansion of small magnitude of the resins. At 20 °C, this expansion takes place just after setting in a poorly consolidated material and is sufficient to induce cracks. In the CEM III/C paste, swelling of the resins also occurs, but before the end of setting, and induces limited stress in the matrix which is still plastic. - Highlights: • Solidification of cationic resins in the Na + -form is investigated. • Portland and blast furnace slag cements are compared. • Deleterious expansion is observed with Portland cement only. • Resin swelling is due to a decrease in the osmotic pressure of the pore solution. • The consolidation rate of the matrix is a key parameter to prevent damage.

Puzzolanic cements of greater resistance at the attack of selenitic waters than the high sulfate resistance portland cements, and viceverse

Directory of Open Access Journals (Sweden)

Talero, Rafael

1987-09-01

Full Text Available This work confirms the certainty of the predictions of useful service given by Kaluosek and al. for the sulphate resistant portland cements (type V, USA, subject to severe selenitic attack. Two sulphate resistant portland cements, were tested by means of the Le Chatelier Anstett method. The tarts were destroyed at ages of three years, having detected in them the presence of thaumasite by XRD. Even so, the impossibility and possibility thaumasite formation was confirmed in pozzolanic cements tarts, which either had or did not have adequate amount of pozzolana (diatomite for such purpose.

Este trabajo confirman las predicciones de vida útil dadas por Kalousek y colaboradores, para los cementos portland de elevada resistencia al ataque de los iones sulfato (tipo V, USA, sometidos a un severo ataque selenitoso. Se ensayaron dos cementos portland de elevada resistencia al ataque del yeso, mediante el ensayo de Le Chatelier-Anstett. Sus tortas correspondientes se destruyeron a la edad de tres años, habiéndose detectado en las mismas la presencia de thaumasita por DRX. Asimismo se confirmó la imposibilidad y posibilidad de formación de thaumasita en tortas de cementos puzolánicos, los cuales tenían, o no, respectivamente, una adecuada cantidad de puzolana (diatomita para tales fines.

Immobilisation of strontium, nickel and iodide by a sulphate-resisting Portland cement

International Nuclear Information System (INIS)

Wieland, E.; Tits, J.; Spieler, P.; Dobler, J.-P.

1998-01-01

The interaction of Sr(II), Ni(II) and I(-I) with sulphate-resisting Portland cement was investigated under highly alkaline conditions. Batch-sorption studies were performed by contacting HTS cement (haute teneur en silice, sulphate-resisting Portland cement, Lafarge, France) with artificial cement pore water (ACW). The composition of ACW was 0.18 M KOH, 0.114 M NaOH and 1.2 mM Ca(OH) 2 . 85 Sr, 63 Ni and 125 I were used as tracers. In the experiments with Sr(II) and Ni(II), isosaccharinic acid (ISA) was added to ACW at 10 -5 M to 10 -2 M in order to study the effect of complexing ligands on radionuclide retention. The stability of the tracer solutions and the cement suspensions were first assessed. Moreover, the inventory of the stable elements were determined in cement and cement pore water. We then studied the kinetics of the radionuclide-cement interaction process and measured the dependence of the distribution ratio (R d ) on the concentration of ISA and on the concentration of cement particles (S:L ratio). In the case of 63 Ni and 125 I a strong decrease in the distribution ratio (R d ) with increasing S:L ratio was observed. There is strong indication that the inventory of the stable fraction of an element present in cement pore water accounts for the retention of the radioisotope fraction. The results further indicate that phase transformations may occur in non-pre-equilibrated cement systems (non-equilibrium conditions) which affect 63 Ni uptake by HTS cement. The distribution ratios measured on HTS cement were compared with values obtained from measurements on important cement components (portlandite, CSH/C(A)SH-phases)

2014 Oregon Department of Geology and Mineral Industries (DOGAMI) Oregon Lidar DEM: Metro Portland, OR

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The dataset encompasses 1221.6 square miles in portions of the greater Portland Metro area in the state of Oregon. The highest hit digital surface models (DSM)...

Concentration of electrolyte reserves of the juvenile african catfish clarias gariepinus (burchell, 1822) exposed to sublethal concentrations of portland cement powder in solution

International Nuclear Information System (INIS)

Adamu, M.K.; Francis, O.A.

2008-01-01

The study investigated the effect of sublethal concentrations (39.10, 19.55, 9.87 and 0.00 mg/l) of Portland cement powder in solution on the electrolyte reserves (sodium, potassium, calcium, chloride and inorganic phosphorus) in the serum, liver and kidney of the juvenile African catfish Clarias gariepinus after a 15 day exposure period. The basic function of the determined electrolyte reserves in the body lies in controlling fluid distribution, intra and extra cellular acidobasic equilibrium, maintaining osmotic pressure of body fluid and normal neuro-muscular irritability. The result revealed significant (P 0.05) changes in inorganic phosphorus. Sodium, calcium, chloride and inorganic phosphorus and potassium were significantly (P 0.05) different in liver and kidney, respectively. Ipso-facto, the effector organs viz: liver and kidney of teleost species - Clarias gariepinus which are primarily responsible for regulating water and ionic movement between external and internal milieu of fishes are susceptible to deleterious effects of Portland cement powder thus sublethal concentration (39.10 mg/l) of Portland cement powder in solution after a 15 day exposure has been most toxic and debilitating to the test fish. (author)

Utilization of the national Portland cement for immobilizing radioactive wastes - Physical characteristics

International Nuclear Information System (INIS)

Rzyski, B.M.; Suarez, A.A.

1988-01-01

This paper shows the results obtained in the study of the national Portland cement, P320, as matrix for radioactive nitric waste incorporation. Cement use practice in other countries is common for this purposes and demonstrates to be cheap and accessible when low and medium level wastes are immobilized. Some of physical characteristics as: homogeneity,mechanical strenght, setting and porosity are analysed due to water-cement ratio and salt contents. Those characteristics which are proper of the final product, must be controlled in such way to assure a long time integrity of the wasteform. The establishment of process and quality control criteria are based in such kind of data. (author) [pt

Interim research assessment 2003-2005 - Computer Science

NARCIS (Netherlands)

Mouthaan, A.J.; Hartel, Pieter H.

This report primarily serves as a source of information for the 2007 Interim Research Assessment Committee for Computer Science at the three technical universities in the Netherlands. The report also provides information for others interested in our research activities.

Relation between Portland cement carbonation, range of clinker burning and some expansive phenomena in the autoclave test

Directory of Open Access Journals (Sweden)

Ruiz de Cauna, A.

1975-12-01

Full Text Available Not availableEn este trabajo se estudia el doble pico que aparece en la región de altas temperaturas de las curvas derivatométricas, realizadas en atmósfera de vapor de agua, de los cementos portland anhidros e hidratados y en general el efecto de la carbonatación sobre los silicatos y aluminatos presentes en los cementos portland, especialmente sobre el perfil de las curvas derivatométricas de los cementos portland anhidros e hidratados. Se recogen y examinan los cambios experimentados en el doble pico al someter los cementos a la acción de diversos tratamientos y de agentes modificantes, tales como el tiempo, el CO2, la hidratación normal, las hidrataciones bajo agua a ebullición, en autoclave y en suspensión acuosa con agitación, la adición de puzolana y de fuertes proporciones de S04Ca. Se estudia y compara, asimismo, el comportamiento al análisis térmico bajo vapor de agua y al ensayo de autoclave de algunos clínkeres y cementos que presentan el doble pico en forma acusada y poco apreciable, respectivamente. De los resultados obtenidos se deducen conclusiones que explican los comportamientos experimentales observados. Las principales conclusiones se refieren a la interpretación de los picos que aparecen en las curvas derivatométricas o de velocidad de pérdida de peso de los cementos portland anhidros e hidratados, y a algunos aspectos de su carbonatación, a la probable existencia de un compuesto intermedio, consecuencia de la incompleta formación del silicato tricálcico y a la explicación de determinadas grandes expansiones producidas en el ensayo de autoclave.

Reinforcement of a PMMA resin for fixed interim prostheses with nanodiamonds.

Science.gov (United States)

Protopapa, Popi; Kontonasaki, Eleana; Bikiaris, Dimitrios; Paraskevopoulos, Konstantinos M; Koidis, Petros

2011-01-01

The aim of this study was to investigate the possible reinforcement of Nanodiamonds (ND) in a PMMA resin for fixed interim restorations. The fracture toughness (K(Ic)), impact strength and the dynamic thermomechanical properties (T(g), E´, E´´, tanδ) of a series of PMMA-ND nanocomposites with different amounts of ND were evaluated. The fracture toughness increased as the ND percentage increased up to 0.38% wt but a greater amount of ND induced a decrease in K(Ic). Impact strength and Young's modulus were also increased by increasing nanoparticles content, indicating the reinforcing effect of ND. Dynamic mechanical properties were also affected. By increasing the ND content an increase of storage modulus was recorded, while glass transition was shifted at higher temperatures. Under the limitations of this study, it can be suggested that reinforcing PMMA with ND nanoparticles -especially at low concentrations- may increase the overall performance of fixed interim prostheses.

A thermodynamic approach to the hydration of sulphate-resisting Portland cement

International Nuclear Information System (INIS)

Lothenbach, Barbara; Wieland, Erich

2006-01-01

A thermodynamic approach is used to model changes in the hydrate assemblage and the composition of the pore solution during the hydration of calcite-free and calcite-containing sulphate-resisting Portland cement CEM I 52.5 N HTS. Modelling is based on thermodynamic data for the hydration products and calculated hydration rates for the individual clinker phases, which are used as time-dependent input parameters. Model predictions compare well with the composition of the hydrate assemblage as observed by TGA and semi-quantitative XRD and with the experimentally determined compositions of the pore solutions. The calculations show that in the presence of small amounts of calcite typically associated with Portland cement, C-S-H, portlandite, ettringite and calcium monocarbonate are the main hydration products. In the absence of calcite in the cement, however, siliceous hydrogarnet instead of calcium monocarbonate is observed to precipitate. The use of a higher water-to-cement ratio for the preparation of a calcite-containing cement paste has a minor effect on the composition of the hydrate assemblage, while it significantly changes the composition of the pore solution. In particular, lower pH value and higher Ca concentrations appear that could potentially influence the solubility and uptake of heavy metals and anions by cementitious materials

75 FR 984 - Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at CERCLA and RCRA Sites

Science.gov (United States)

2010-01-07

...The Environmental Protection Agency (EPA or the Agency) is announcing a 50-day public comment period for draft recommended interim preliminary remediation goals (PRGs) developed in the Draft Recommended Interim Preliminary Remediation Goals for Dioxin in Soil at Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and Resource Conservation and Recovery Act (RCRA) Sites. EPA's Office of Solid Waste and Emergency and Emergency Response (OSWER) has developed the draft recommended interim PRGs for dioxin in soil. These draft recommended interim PRGs were calculated using existing, peer- reviewed toxicity values and current EPA equations and default exposure assumptions. This Federal Register notice is intended to provide an opportunity for public comment on the draft recommended interim PRGs. EPA will consider any public comments submitted in accordance with this notice and may revise the draft recommended interim PRGs thereafter.

Mechanical characterization of Portland cement mortars containing petroleum or coal tar

Directory of Open Access Journals (Sweden)

Garcés, P.

2007-08-01

Full Text Available This article discusses experimental data on the flexural and compressive strength of Portland cement mortars containing additions or cement replacements consisting in petroleum or coal tar, by-products of the oil and coal industries. The materials studied were two coal (BACA and BACB and two petroleum (BPP and BPT tars. The results show that it is feasible to use such materials as a partial replacement for cement in mortar manufacture. This should lead to the design of a new sustainable product that will contribute to lowering the environmental impact of construction materials while at the same time opening up an avenue for the re-use of this type of industrial by-products.En este artículo se presentan datos experimentales de resistencia a flexión y a compresión de morteros de cemento Portland con adición y sustitución de breas de petróleo y de alquitrán de carbón, que son subproductos de la industria del carbón o del petróleo. Los materiales estudiados son breas de alquitrán de carbón A (BACA y B (BACB, y dos breas de petróleo (BPP y (BPT. Los datos demuestran la viabilidad del uso de estas breas en la fabricación de morteros con menores contenidos de cemento, permitiendo diseñar un nuevo material sostenible con el medio ambiente y que contribuya a reducir el impacto ambiental de los materiales de construcción, hecho que permite abrir una nueva vía de valorización de estos subproductos.

Análise microscópica da polpa dental de cães após pulpotomia e proteção pulpar com agregado de trióxido mineral e cimento Portland branco

OpenAIRE

Menezes, Renato; Bramante, Clóvis Monteiro; Garcia, Roberto Brandão; Letra, Ariadne; Carvalho, Vanessa Graciela Gomes; Carneiro, Everdan; Brunini, Sérgio; Oliveira, Rodrigo Cardoso; Canova, Giovana Calichio; Moraes, Fernanda Gomes de

2004-01-01

Considering previous studies on the similarity between the chemical composition of the mineral trioxide aggregate and the Portland cement, the purpose of this study was to investigate the pulp response of dog's teeth after pulpotomy and direct pulp protection with MTA Angelus and white Portland cement. Thirty eight pulp remnants were protected with these materials. One hundred and twenty days after treatment, the animals were sacrificed and the specimens removed and prepared for histological ...

DATA MINING METHODOLOGY FOR DETERMINING THE OPTIMAL MODEL OF COST PREDICTION IN SHIP INTERIM PRODUCT ASSEMBLY

Directory of Open Access Journals (Sweden)

Damir Kolich

2016-03-01

Full Text Available In order to accurately predict costs of the thousands of interim products that are assembled in shipyards, it is necessary to use skilled engineers to develop detailed Gantt charts for each interim product separately which takes many hours. It is helpful to develop a prediction tool to estimate the cost of interim products accurately and quickly without the need for skilled engineers. This will drive down shipyard costs and improve competitiveness. Data mining is used extensively for developing prediction models in other industries. Since ships consist of thousands of interim products, it is logical to develop a data mining methodology for a shipyard or any other manufacturing industry where interim products are produced. The methodology involves analysis of existing interim products and data collection. Pre-processing and principal component analysis is done to make the data “user-friendly” for later prediction processing and the development of both accurate and robust models. The support vector machine is demonstrated as the better model when there are a lower number of tuples. However as the number of tuples is increased to over 10000, then the artificial neural network model is recommended.

Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement.

Science.gov (United States)

Marciano, Marina Angélica; Garcia, Roberto Brandão; Cavenago, Bruno Cavalini; Minotti, Paloma Gagliardi; Midena, Raquel Zanin; Guimarães, Bruno Martini; Ordinola-Zapata, Ronald; Duarte, Marco Antonio Hungaro

2014-01-01

To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement. White Portland cement (WPC) was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6). The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p0.05). For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05). The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (pPortland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated.

Industrial Wastes as Alternative Mineral Addition in Portland Cement and as Aggregate in Coating Mortars

OpenAIRE

Oliveira, Kamilla Almeida; Nazário, Bruna Inácio; Oliveira, Antonio Pedro Novaes de; Hotza, Dachamir; Raupp-Pereira, Fabiano

2017-01-01

This paper presents an evaluation study of wastes from pulp and paper as well as construction and demolition industries for application in cement-based materials. The alternative raw materials were used as a source of calcium carbonate (CaCO3) and as pozzolanic material (water-reactive SiO2) in partial replacement of Portland cement. In addition to the hydraulic binder, coating mortars were composed by combining the pulp and paper fluidized bed sand residue with construction and demolition wa...

18 CFR 300.20 - Interim acceptance and review of Bonneville Power Administration rates.

Science.gov (United States)

2010-04-01

... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Interim acceptance and review of Bonneville Power Administration rates. 300.20 Section 300.20 Conservation of Power and Water... Director of the Office of Energy Market Regulation; or (ii) Deny the Administrator's interim rate request...

Fuel Supply Shutdown Facility Interim Operational Safety Requirements

International Nuclear Information System (INIS)

BENECKE, M.W.

2000-01-01

The Interim Operational Safety Requirements for the Fuel Supply Shutdown (FSS) Facility define acceptable conditions, safe boundaries, bases thereof, and management of administrative controls to ensure safe operation of the facility

A web-based endpoint adjudication system for interim analyses in clinical trials.

Science.gov (United States)

Nolen, Tracy L; Dimmick, Bill F; Ostrosky-Zeichner, Luis; Kendrick, Amy S; Sable, Carole; Ngai, Angela; Wallace, Dennis

2009-02-01

A data monitoring committee (DMC) is often employed to assess trial progress and review safety data and efficacy endpoints throughout a trail. Interim analyses performed for the DMC should use data that are as complete and verified as possible. Such analyses are complicated when data verification involves subjective study endpoints or requires clinical expertise to determine each subject's status with respect to the study endpoint. Therefore, procedures are needed to obtain adjudicated data for interim analyses in an efficient manner. In the past, methods for handling such data included using locally reported results as surrogate endpoints, adjusting analysis methods for unadjudicated data, or simply performing the adjudication as rapidly as possible. These methods all have inadequacies that make their sole usage suboptimal. For a study of prophylaxis for invasive candidiasis, adjudication of both study eligibility criteria and clinical endpoints prior to two interim analyses was required. Because the study was expected to enroll at a moderate rate and the sponsor required adjudicated endpoints to be used for interim analyses, an efficient process for adjudication was required. We created a web-based endpoint adjudication system (WebEAS) that allows for expedited review by the endpoint adjudication committee (EAC). This system automatically identifies when a subject's data are complete, creates a subject profile from the study data, and assigns EAC reviewers. The reviewers use the WebEAS to review the subject profile and submit their completed review form. The WebEAS then compares the reviews, assigns an additional review as a tiebreaker if needed, and stores the adjudicated data. The study for which this system was originally built was administratively closed after 10 months with only 38 subjects enrolled. The adjudication process was finalized and the WebEAS system activated prior to study closure. Some website accessibility issues presented initially. However

Effect of calcium/silicon ratio on retention of uranium (VI) in portland cement materials

International Nuclear Information System (INIS)

Tan Hongbin; Li Yuxiang

2005-01-01

Calcium silicate hydrate (CSH) materials of varied calcium to silicon (Ca/Si) ratios were prepared by hydrothermal synthesis at 80 degree C, with calcium oxide and micro-silicon employed. These products were determined to be of gel phase by XRD. Leaching tests with 1% hydrochloric acid indicated that more Uranium (VI) was detained by CSH with lower Ca/Si ratios. Alkali-activated slag cement (with a lower Ca/Si ratio) was found to have a stronger retention capacity than Portland cement (with a higher Ca/Si ratio), at 25 degree C in 102-days leaching tests with simulated solidified forms containing Uranium (VI). The accumulative leaching fraction of Uranium (VI) for Alkali-activated slag cement solidified forms is 17.6% lower than that for Portland cement. The corresponding difference of diffusion coefficients is 40.6%. This could be correlated with the difference of Ca/Si ratios between cements of two kinds. (authors)

Measurement of the leaching rate of radionuclide 134Cs from the solidified radioactive sources in Portland cement mixed with microsilica and barite matrixes

International Nuclear Information System (INIS)

Shaaban, Ismail; Assi, Nasim

2011-01-01

Portland cement was mixed with radionuclide 134 Cs to produce low-level radioactive sources. These sources were surrounded with cement mixed with different materials like microsilica and barite. The leaching rate of 134 Cs from the solidified radioactive source in Portland cement alone was found to be 4.481 x 10 -4 g/cm 2 per day. Mixing this Portland cement with microsilica and with barite reduced significantly the leaching rate to 1.091 x 10 -4 g/cm 2 per day and 3.153 x 10 -4 g/cm 2 per day for 1 wt.% mixing, and to 1.401 x 10 -5 g/cm 2 per day and 1.703 x 10 -4 g/cm 2 per day for 3 wt.% mixing, respectively. It was also found that the application of a latex paint reduced these leaching rates by about 6.5%, 20.3% and 13.3% for Portland cement, cement mixed with microsilica and with barite, respectively. The leaching data were also analyzed using the polynomial method. The obtained results showed that cement mixed with microsilica and with barite can be effectively used for radioactive sources solidification.

Properties of expansive cements, made with Portland cement, gypsum and high alumina cement

Directory of Open Access Journals (Sweden)

Monfore, G. E.

1966-03-01

Full Text Available Not availableLos cementos expansivos se han desarrollado durante las tres décadas pasadas, principalmente por las investigaciones llevadas a cabo en Francia, URSS y Estados Unidos. Los cementos expansivos que fueron utilizados en los estudios de los cuales se da cuenta en el presente trabajo se obtuvieron mediante la mezcla de cemento Portland, cemento aluminoso y yeso. En las investigaciones se utilizaron morteros con los cuales se pudo determinar los efectos de la composición, tiempo y temperatura de curado sobre las resistencias, dilatación libre, retracción y desarrollo de resistencias en probetas pretensadas. Se hace una revisión sobre los estudios hechos con cementos expansivos y desarrollados en la Universidad de California. Las propiedades de taIes hormigones son, en términos generales, comparables a aquellos obtenidos con mezclas de cementos portland, cemento aluminoso y yeso. Es necesaria más información sobre pérdidas de tensión en los aceros y durabilidad de los hormigones autopretensados.

Latex-modified fiber-reinforced concrete bridge deck overlay : construction/interim report.

Science.gov (United States)

1993-06-01

Latex-modified concrete (LMC) is Portland cement concrete (PCC) with an admixture of latex. LMC is considered to be nearly impermeable to chlorides and is extensively used to construct bridge deck overlays. Unfortunately, some of these overlays have ...

Subsurface Interim Measures/Interim Remedial Action Plan and Decision Document for the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2)

International Nuclear Information System (INIS)

1992-01-01

The Department of Energy (DOE) is pursuing an Interim Measure/Interim Remedial Action (IM/IRA) at the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2) at the Rocky Flats Plant (RFP). This MIRA is to be conducted to provide information that will aid in the selection and design of final remedial actions at OU2 that will address removal of suspected free-phase volatile organic compound (VOC) contamination. The Plan involves investigating the removal of residual free-phase VOCs by in situ vacuum-enhanced vapor extraction technology at 3 suspected VOC source areas within OU2. VOC-contaminated vapors extracted from the subsurface would be treated by granular activated carbon (GAC) adsorption and discharged. The Plan also includes water table depression, when applicable at the test sites, to investigate the performance of vapor extraction technology in the saturated zone. The Plan provides for treatment of any contaminated ground water recovered during the IM/IRA at existing RFP treatment facilities. The proposed MVIRA Plan is presented in the document entitled ''Proposed Subsurface Interim Measures/Interim Remedial Action Plan/Environmental Assessment and Decision Document, 903 Pad, Mound, and East Trenches Areas, Operable Unit No. 2, '' dated 20 March 1992. Information concerning the proposed Subsurface IM/IRA was presented during a DOE Quarterly Review meeting held on 07 April 1992 and a public meeting held on 07 May 1992, at the Marriott Hotel in Golden, Colorado. The Responsiveness Summary presents DOE's response to all comments received at the public meeting, as well as those mailed to date to DOE during the public comment period

Radioactive waste-Portland cement systems: I, radionuclide distribution

International Nuclear Information System (INIS)

Jantzen, C.M.; Glasser, F.P.; Lachowski, E.E.

1984-01-01

Crystal chemical stabilization of radioactive wastes can be achieved during clinkering of, or with, ordinary portland cement. Waste loadings of 20 to 30 wt% are achieved by dilute solid solution of waste ions into cementitious host lattices. Higher waste loadings result in compatible noncementitious radiophases. The cementitious phases hydrate without loss of compressive strength. Crystallochemical relationships predict that the radionuclide partitioning in the anhydrous clinkered phases will be maintained in the hydration products. These cementitious hydroxylated radiophases would be in internal equilibrium under anticipated repository conditions. The radionuclide distributions observed are described in the context of established phase equilibria for commercial waste cement systems, but are applicable to transuranic, medium- and low-level wastes

Used Fuel Logistics: Decades of Experience with transportation and Interim storage solutions

Energy Technology Data Exchange (ETDEWEB)

Orban, G.; Shelton, C.

2015-07-01

Used fuel inventories are growing worldwide. While some countries have opted for a closed cycle with recycling, numerous countries must expand their interim storage solutions as implementation of permanent repositories is taking more time than foreseen. In both cases transportation capabilities will have to be developed. AREVA TN has an unparalleled expertise with transportation of used fuel. For more than 50 years AREVA TN has safely shipped more than 7,000 used fuel transport casks. The transportation model that was initially developed in the 1970s has been adapted and enhanced over the years to meet more restrictive regulatory requirements and evolving customer needs, and to address public concerns. The numerous “lessons learned” have offered data and guidance that have allowed for also efficient and consistent improvement over the decades. AREVA TN has also an extensive experience with interim dry storage solutions in many countries on-site but also is working with partners to developed consolidated interim storage facility. Both expertise with storage and transportation contribute to safe, secure and smooth continuity of the operations. This paper will describe decades of experience with a very successful transportation program as well as interim storage solutions. (Author)

Large-scale Meteorological Patterns Associated with Extreme Precipitation Events over Portland, OR

Science.gov (United States)

Aragon, C.; Loikith, P. C.; Lintner, B. R.; Pike, M.

2017-12-01

Extreme precipitation events can have profound impacts on human life and infrastructure, with broad implications across a range of stakeholders. Changes to extreme precipitation events are a projected outcome of climate change that warrants further study, especially at regional- to local-scales. While global climate models are generally capable of simulating mean climate at global-to-regional scales with reasonable skill, resiliency and adaptation decisions are made at local-scales where most state-of-the-art climate models are limited by coarse resolution. Characterization of large-scale meteorological patterns associated with extreme precipitation events at local-scales can provide climatic information without this scale limitation, thus facilitating stakeholder decision-making. This research will use synoptic climatology as a tool by which to characterize the key large-scale meteorological patterns associated with extreme precipitation events in the Portland, Oregon metro region. Composite analysis of meteorological patterns associated with extreme precipitation days, and associated watershed-specific flooding, is employed to enhance understanding of the climatic drivers behind such events. The self-organizing maps approach is then used to characterize the within-composite variability of the large-scale meteorological patterns associated with extreme precipitation events, allowing us to better understand the different types of meteorological conditions that lead to high-impact precipitation events and associated hydrologic impacts. A more comprehensive understanding of the meteorological drivers of extremes will aid in evaluation of the ability of climate models to capture key patterns associated with extreme precipitation over Portland and to better interpret projections of future climate at impact-relevant scales.

Success of Two-Stage Reimplantation in Patients Requiring an Interim Spacer Exchange.

Science.gov (United States)

George, Jaiben; Miller, Evan M; Curtis, Gannon L; Klika, Alison K; Barsoum, Wael K; Mont, Michael A; Higuera, Carlos A

2018-03-23

Some patients undergoing a 2-stage revision for a periprosthetic joint infection require a repeat spacer in the interim (removal of existing spacer with insertion of a new spacer or spacer exchange) due to persistent infection. The objectives of this study are to (1) determine the factors associated with patients who receive a repeat spacer and (2) compare the infection-free survival (overall and stratified by joint type) of reimplantation in patients who did or did not receive a repeat spacer. From 2001 to 2014, 347 hip or knee 2-stage revisions that finally underwent reimplantation and had a minimum 2-year follow-up were identified. An interim spacer exchange was performed in 59 (17%) patients (exchange cohort). Patient-related and organism-related factors were compared between the exchange and non-exchange cohorts. Kaplan-Meier survival curves were performed to assess the success (absence of signs of infection, reoperation for infection, periprosthetic joint infection-related mortality) of both cohorts. Patients in the exchange group had higher comorbidity score (P = .020), prolonged time to reimplantation (P exchange cohort, and 78% (knee 77%, hip 78%) in the non-exchange cohort (P = .020). Patients requiring an interim spacer exchange were found to have more comorbidities, prolonged treatment period, and were more likely to be infected with a resistant organism. About one-third of such patients became reinfected within 5 years compared to only one-fifth of the patients without an interim spacer exchange. Copyright © 2018 Elsevier Inc. All rights reserved.

Solidification of ion exchange resins saturated with Na{sup +} ions: Comparison of matrices based on Portland and blast furnace slag cement

Energy Technology Data Exchange (ETDEWEB)

Lafond, E. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Cau dit Coumes, C., E-mail: celine.cau-dit-coumes@cea.fr [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Gauffinet, S. [Laboratoire Interdisciplinaire Carnot de Bourgogne UMR 6303 CNRS-Université de Bourgogne, Dijon, France, 9 Av Alain Savary, BP 47870, 21078 Dijon cedex (France); Chartier, D. [CEA, DEN, DTCD, SPDE, F-30207 Bagnols-sur-Cèze cedex (France); Stefan, L. [AREVA, Back End Business Group, Dismantling & Services, 1 Place Jean Millier, 92084 Paris La Défense (France); Le Bescop, P. [CEA, DEN, DPC, SECR, F-91192 Gif-sur-Yvette (France)

2017-01-15

This work is devoted to the conditioning of ion exchange resins used to decontaminate radioactive effluents. Calcium silicate cements may have a good potential to encapsulate spent resins. However, certain combinations of cement and resins produce a strong expansion of the final product, possibly leading to its full disintegration. The focus is placed on the understanding of the behaviour of cationic resins in the Na{sup +} form in Portland or blast furnace slag (CEM III/C) cement pastes. During hydration of the Portland cement paste, the pore solution exhibits a decrease in its osmotic pressure, which causes a transient expansion of small magnitude of the resins. At 20 °C, this expansion takes place just after setting in a poorly consolidated material and is sufficient to induce cracks. In the CEM III/C paste, swelling of the resins also occurs, but before the end of setting, and induces limited stress in the matrix which is still plastic. - Highlights: • Solidification of cationic resins in the Na{sup +}-form is investigated. • Portland and blast furnace slag cements are compared. • Deleterious expansion is observed with Portland cement only. • Resin swelling is due to a decrease in the osmotic pressure of the pore solution. • The consolidation rate of the matrix is a key parameter to prevent damage.

Preparation and Physical Assessment of Portland Cement Base Composites Containing Nano Particles

OpenAIRE

Amir Mahmoudi

2015-01-01

In this research the effects of adding silica and alumina nanoparticles on flow ability and compressive strength of cementitious composites based on Portland cement were investigated. In the first stage, the rheological behavior of different samples containing nanosilica, nanoalumina and polypropylene, polyvinyl alcohol and polyethylene fibers were evaluated. With increasing of nanoparticles in fresh samples, the slump flow diameter reduced. Fibers reduced the flow abilit...

On-site interim storage of spent nuclear fuel: Emerging public issues

International Nuclear Information System (INIS)

Feldman, D.L.; Tennessee Univ., Knoxville, TN

1992-01-01

Failure to consummate plans for a permanent repository or above- ground interim Monitored Retrievable Storage (MRS) facility for spent nuclear fuel has spurred innovative efforts to ensure at-reactor storage in an environmentally safe and secure manner. This article examines the institutional and socioeconomic impacts of Dry Cask Storage Technology (DCST)-an approach to spent fuel management that is emerging as the preferred method of on-site interim spent fuel storage by utilities that exhaust existing storage capacity

Manufacturing of mortars and concretes non-traditionals, by Portland cement, metakaoline and gypsum (15.05%

Directory of Open Access Journals (Sweden)

Talero, R.

1999-12-01

Full Text Available In a thorough previous research (1, it appeared that creation, evolution and development of the values of compressive mechanical strength (CS and flexural strength (FS, measured in specimens 1x1x6cm of mortar type ASTM C 452-68 (2, manufactured by ordinary Portland cement P-1 (14.11% C₃A or PY-6 (0.00% C₃A, metakaolin and gypsum (CaSO₄∙2H₂O -or ternary cements, CT-, were similar to the ones commonly developed in mortars and concretes of OPC. This paper sets up the experimental results obtained from non-traditional mortars and concretes prepared with such ternary cements -TC-, being the portland cement/metakaolin mass ratio, as follows: 80/20, 70/30 and 60/40. Finally, the behaviour of these cements against gypsum attack, has been also determined, using the following parameters: increase in length (ΔL%, compressive, CS, and flexural, FS, strengths, and ultrasound energy, UE. Experimental results obtained from these non-traditional mortars and concretes, show an increase in length (ΔL, in CS and FS, and in UE values, when there is addition of metakaolin.

En una exhaustiva investigación anterior (1, se pudo comprobar que la creación, evolución y desarrollo de los valores de resistencias mecánicas a compresión, RMC, y flexotracción, RMF, proporcionados por probetas de 1x1x6 cm, de mortero 1:2,75, selenitoso tipo ASTM C 452-68 (2 -que habían sido preparadas con arena de Ottawa, cemento portland, P-1 (14,11% C₃A o PY- 6 (0,00% C₃A, metacaolín y yeso (CaSO₄∙2H₂O-, fue semejante a la que, comúnmente, desarrollan los morteros y hormigones tradicionales de cemento portland. En el presente trabajo se exponen los resultados experimentales obtenidos de morteros y hormigones no tradicionales, preparados con dichos cementos ternarios, CT, siendo las proporciones porcentuales en masa ensayadas, cemento portland/metacaolín, las siguientes: 80/20, 70

Environmental assessment for 881 Hillside (High Priority Sites) interim remedial action

International Nuclear Information System (INIS)

1990-01-01

This Environmental Assessment evaluates the impact of an interim remedial action proposed for the High Priority Sites (881 Hillside Area) at the Rocky Flats Plant (RFP). This interim action is to be conducted to minimize the release of hazardous substances from the 881 Hillside Area that pose a potential long-term threat to public health and the environment. This document integrates current site characterization data and environmental analyses required by the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) or ''Superfund'' process, into an environmental assessment pursuant to the National Environmental Policy Act (NEPA). Characterization of the 881 Hillside Area is continuing. Consequently, a final remedial action has not yet been proposed. Environmental impacts associated with the proposed interim remedial action and reasonable alternatives designed to remove organic and inorganic contaminants, including radionuclides, from alluvial groundwater in the 881 Hillside Area are addressed. 24 refs., 5 figs., 23 tabs

Transitioning aluminum clad spent fuels from wet to interim dry storage

International Nuclear Information System (INIS)

Louthan, M.R. Jr.; Iyer, N.C.; Sindelar, R.L.; Peacock, H.B. Jr.

1994-01-01

The United States Department of Energy (DOE) currently owns several hundred metric tons of aluminum clad, spent nuclear fuel and target assemblies. The vast majority of these irradiated assemblies are currently stored in water basins that were designed and operated for short term fuel cooling prior to fuel reprocessing. Recent DOE decisions to severely limit the reprocessing option have significantly lengthened the time of storage, thus increasing the tendency for corrosion induced degradation of the fuel cladding and the underlying core material. The portent of continued corrosion, coupled with the age of existing wet storage facilities and the cost of continuing basin operations, including necessary upgrades to meet current facility standards, may force the DOE to transition these wet stored, aluminum clad spent fuels to interim dry storage. The facilities for interim dry storage have not been developed, partially because fuel storage requirements and specifications for acceptable fuel forms are lacking. In spite of the lack of both facilities and specifications, current plans are to dry store fuels for approximately 40 to 60 years or until firm decisions are developed for final fuel disposition. The transition of the aluminum clad fuels from wet to interim dry storage will require a sequence of drying and canning operations which will include selected fuel preparations such as vacuum drying and conditioning of the storage atmosphere. Laboratory experiments and review of the available literature have demonstrated that successful interim dry storage may also require the use of fuel and canister cleaning or rinsing techniques that preclude, or at least minimize, the potential for the accumulation of chloride and other potentially deleterious ions in the dry storage environment. This paper summarizes an evaluation of the impact of fuel transitioning techniques on the potential for corrosion induced degradation of fuel forms during interim dry storage

The Estimation of Compaction Parameter Values Based on Soil Properties Values Stabilized with Portland Cement

Science.gov (United States)

Lubis, A. S.; Muis, Z. A.; Pasaribu, M. I.

2017-03-01

The strength and durability of pavement construction is highly dependent on the properties and subgrade bearing capacity. This then led to the idea of the selection methods to estimate the density of the soil with the proper implementation of the system, fast and economical. This study aims to estimate the compaction parameter value namely the maximum dry unit weight (γd max) and optimum moisture content (wopt) of the soil properties value that stabilized with Portland Cement. Tests conducted in the laboratory of soil mechanics to determine the index properties (fines and liquid limit) and Standard Compaction Test. Soil samples that have Plasticity Index (PI) between 0-15% then mixed with Portland Cement (PC) with variations of 2%, 4%, 6%, 8% and 10%, each 10 samples. The results showed that the maximum dry unit weight (γd max) and wopt has a significant relationship with percent fines, liquid limit and the percentation of cement. Equation for the estimated maximum dry unit weight (γd max) = 1.782 - 0.011*LL + 0,000*F + 0.006*PS with R2 = 0.915 and the estimated optimum moisture content (wopt) = 3.441 + 0.594*LL + 0,025*F + 0,024*PS with R2 = 0.726.

Assessment of diabetic teleretinal imaging program at the Portland Department of Veterans Affairs Medical Center.

Science.gov (United States)

Tsan, Grace L; Hoban, Keely L; Jun, Weon; Riedel, Kevin J; Pedersen, Amy L; Hayes, John

2015-01-01

We conducted a retrospective chart review of 200 diabetic patients who had teleretinal imaging performed between January 1, 2010, and January 1, 2011, at Portland Department of Veterans Affairs (VA) Medical Center outpatient clinics to assess the effectiveness of the diabetic teleretinal imaging program. Twenty patients (10%) had diabetic retinopathy. Ninety percent of the available teleretinal imaging studies were of adequate quality for interpretation. In accordance with local VA policy at that time, all teleretinal imaging patients should have been referred for a dilated retinal examination the following year. Image readers referred 97.5% of the patients to eye clinics for subsequent eye examinations, but the imagers scheduled appointments for only 80% of these patients. The redundancy rate, i.e., patients who had an eye examination within the past 6 mo, was 11%; the duplicate recall rate, i.e., patients who had a second teleretinal imaging performed within 1 yr of the eye examination, was 37%. Rates of timely diabetic eye examinations at clinics with teleretinal imaging programs, particularly when teleretinal imaging and eye clinics were colocated at the same community-based outpatient clinic, were higher than those without a teleretinal imaging program. We concluded that the Portland VA Medical Center's teleretinal imaging program was successful in increasing the screening rate for diabetic retinopathy.

Parameters of Alumina Cement and Portland Cement with Addition of Chalcedonite Meal

Science.gov (United States)

Kotwa, Anna

2017-10-01

Aluminous cement is a quick binder with special properties. It is used primarily to make non-standard monolithic components exposed to high temperatures, + 1300°C. It is also a component of adhesives and mortars. It has a very short setting time. It is characterized by rapid increase in mechanical strength and resistance to aggressive sulphates. It can be used in reinforced concrete structures. Laying of concrete, construction mortar made of alumina cement can be carried out even at temperatures of -10°C. This article discusses a comparison of the parameters of hardened mortar made of alumina cement GÓRKAL 40 and Portland cement CEM I 42.5R. The mortars contain an addition of chalcedonite meal with pozzolanic properties, with particle size of less than 0.063μm. The meal was added in amounts of 5% and 20% of cement weight. Chalcedonite meal used in the laboratory research is waste material, resulting from chalcedonite aggregate mining. It has the same properties as the rock from which it originates. We have compared the parameters of hardened mortar i.e. compressive strength, water absorption and capillarity. The addition of 20% chalcedonite meal to mortars made from aluminous cement will decrease durability by 6.1% relative to aluminous cement mortar without addition of meal. Considering the results obtained during the absorbency tests, it can be stated that the addition of chalcedonite meal reduces weight gains in mortars made with cement CEM I 42.5 R and alumina cement. Use of alumina cement without addition of meal in mortars causes an increase of mass by 248% compared to Portland cement mortars without additions, in the absorption tests. The addition of chalcedonite meal did not cause increased weight gain in the capillary action tests. For the alumina cement mortars, a lesser weight gains of 24.7% was reported, compared to the Portland cement mortar after 28 days of maturing.

Alkali segregation in Portland cement pastes

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Triviño, F.

1966-09-01

Full Text Available Not availableEn el presente trabajo se pone de manifiesto experimentalmente la formación y presencia de aphthitalita -sulfato doble de potasio y sodio en la relación S04K2/S04Na2 = 3/1 en las pastas puras de cemento portland, desde el comienzo del fraguado de las mismas. Se estudia el mecanismo de la citada formación, íntimamente relacionada con el proceso general de formación de eflorescencias salinas, a base de una emigración de sulfatos alcalinos hacia las partes externas de las pastas, en virtud de fenómenos de exudación equivalentes a arrastres capilares. Se sintetiza y aísla la aphthitalita por dos procedimientos y se obtiene su difractograma.de rayos· X, a efectos de su identificación y de la confirmación de los resultados experimentales obtenidos, así como de la interpretación de los mismos.

CALCIUM ORTHOPHOSPHATES HYDRATES: FORMATION, STABILITY AND INFLUENCE ON STANDARD PROPERTIES OF PORTLAND CEMENT

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Kaziliunas A.

2013-12-01

Full Text Available Preparation of phosphogypsum to produce the binders requires a much higher input than preparation of natural gypsum stone. This makes it uncompetitive material. The investigations presented therein are meant to reduce this input by looking for the ways of rendering impurities harmless. Soluble acid orthophosphates are the main harmful impurity of phosphogypsum. The studies show that dry insoluble calcium orthophosphates hydrates (1.09 % and 2.18 % P2O5 in gypsum have little effect on W/C, setting times and soundness of Portland cement pastes. Insoluble calcium orthophosphates hydrates {CaHPO4∙2H2O, Ca8(HPO42(PO44∙5H2O and Ca9(HPO4(PO45(OH∙4H2O} formed in acidic medium (pH = 4.2 - 5.9 have been destroyed in alkaline medium and reduce standard compressive strength of cement up to 28 %. Calcium orthophosphates hydrates of hydroxyapatite group are stable in alcaline medium, while in dry state they reduce the standard compressive strength of cement until 10 %, but their suspensions prolong setting times of Portland cement as soluble orthophosphates – 2 - 3 times. Alkalis in cement increase pH of paste, but do not change the process of formation of calcium orthophosphates hydrates of hydroxyapatite group: it takes place through an intermediate phase - CaHPO4·2H2O, whose transformation into apatite lasts for 2 - 3 months.

Portland's experience with land use tools to promote green roofs

International Nuclear Information System (INIS)

Johnson, M.

2004-01-01

In the late 1990s, the City of Portland, Oregon faced environmental challenges that prompted the City to mandate environmentally sensitive development. Several programs were developed in response to these challenges, some of which resulted in the creation of land use policies and incentives that promote green roofs. Zoning code provisions were adopted in 2001 to promote eco-roofs in an effort to reduce stormwater runoff, mitigate urban heat island effects, provide habitat for birds, and improve air quality and energy efficiency. The Central City Fundamental Design Guidelines were also revised to encourage eco-roof development. In 2002, the South Waterfront Plan was created to integrate ecological design into an urban environment through sustainability principles and practices. Land use tools were developed to introduce developers to an approach that reduced energy costs and stormwater costs, while also contributing to a project's marketability. These tools were created with the support of programs and policies such as the CSO (Combined Sewer Overflow) Program; eco-roof research which began in 1995 to determine the stormwater management potential of eco-Green roofs; technical assistance to encourage and highlight sustainable development practices; the Stormwater Management Manual that set standards for the amount and quality of stormwater runoff leaving development sites; the G/Rated Program that offers resources for green building practices; the Green Investment Fund that supports the G/Rated Program; and, the Portland Development Commission Green Building Policy financing tool for earth-friendly designs and materials. 34 refs., 2 figs

Observational Study of IncobotulinumtoxinA for Cervical Dystonia or Blepharospasm (XCiDaBLE: Interim Results for the First 170 Subjects with Blepharospasm

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Hubert H. Fernandez

2014-07-01

Full Text Available Background: XCiDaBLE is a large, prospective, observational “naturalistic” study evaluating Xeomin® for Cervical Dystonia or BLEpharospasm in the United States. We report the interim results from the blepharospasm cohort of XCiDaBLE.Methods: Subjects (≥18 years old with blepharospasm were followed for two treatment cycles of incobotulinumtoxinA and monitored for 4 weeks after injection via interactive voice/web response system (IVRS/IWRS. The investigator‐reported scale includes the Clinical Global Impression Scale‐Severity subscale (CGI‐S. Patient‐reported outcome measures include the Patient Global Impression Scale‐Severity (PGI‐S and ‐Improvement (PGI‐I subscales, Jankovic Rating Scale (JRS, SF‐12v2® health survey, and Work Productivity and Activity Impairment questionnaire. Subjects are seen by the investigator at baseline (including the first injection, during the second injection, and at a final study visit (12 weeks after the second injection.Results: One hundred seventy subjects were included in this interim analysis. The majority of subjects were female (77.1% and white (91.8%, and had previously been treated with botulinum toxins (96.5%. The mean total dose (both eyes was 71.5 U of incobotulinumtoxinA for the first injection. PGI‐S, PGI‐I, and JRS scores were significantly improved 4 weeks after treatment (all p<0.0001. No differences were noted in either quality of life (QoL or work productivity in this short assessment period. No unexpected adverse events occurred.Discussion: This is an interim study and assessment method based on an IVRS/IWRS. In this predominantly toxin‐experienced cohort, significant benefits in specific and global measures of disease severity were seen in the immediate post‐incobotulinumtoxinA injection period. It will be interesting to see if there are improvements in QoL with consistent individualized injections over a longer period.

Surface Water Interim Measures/Interim Remedial Action Plan/ Environmental and Decision Document, South Walnut Creek Basin, Operable Unit No.2

International Nuclear Information System (INIS)

1991-01-01

Water quality investigations have identified the presence of volatile organic compound (VOC) and radionuclide contamination of surface water at the Rocky Flats Plant (RFP). The subject interim Measures/Interim Remedial Action Plan/Environmental Assessment (IM/IRAP/EA) addresses contaminated surface water in a portion of the South Walnut Creek drainage basin located within an area identified as Operable Unit No. 2 (OU 2). There is no immediate threat to public health and the environment posed by this surface water contamination. The affected surface water is contained within the plant boundary by existing detention ponds, and is treated prior to discharge for removal of volatile contaminants and suspended particulates to which radionuclides, if present, are likely to absorb. However, there is a potential threat and the Department of Energy (DOE) is implementing this Surface Water IM/IRAP at the request of the US Environmental Protection Agency (EPA) and Colorado Department of Health (CDH). Implementation of the Surface Water IM/IRA will enhance the DOE's efforts towards containing and managing contaminated surface water, and will mitigate downgradient migration of contaminants. Another factor in implementing this IM/IRA is the length of time it will take to complete the investigations and engineering studies necessary to determine the final remedy for OU 2. 44 refs., 23 figs., 14 tabs

Administrative Court Stade, decision of March 22, 1985 (interim storage facility at Gorleben)

International Nuclear Information System (INIS)

Anon.

1985-01-01

This decision deals with the planned interim storage facility of Gorleben (F.R.G.). The provisions introduced by the 4th ammendment to sec. 5 para. 6 and 9a to 9c of the German Atomic Energy Act might contain a definite regulation of the 'Entsorgung' of nuclear power stations. Sec. 6 of the Atomic Energy Act is not applicable to interim storage facilities because irradiated nuclear fuel has a double nature: It is spent fuel and nuclear waste as well. Considering current licensing procedures of construction and operation of nuclear installations in the field of 'Entsorgung', special legal regulations for the construction and operation of an interim storage facility have to be required. (CW)

A cognitive stressor for event-related potential studies: the Portland arithmetic stress task.

Science.gov (United States)

Atchley, Rachel; Ellingson, Roger; Klee, Daniel; Memmott, Tabatha; Oken, Barry

2017-05-01

In this experiment, we developed and evaluated the Portland Arithmetic Stress Task (PAST) as a cognitive stressor to evaluate acute and sustained stress reactivity for event-related potential (ERP) studies. The PAST is a titrated arithmetic task adapted from the Montreal Imaging Stress Task (MIST), with added experimental control over presentation parameters, improved and synchronized acoustic feedback and generation of timing markers needed for physiological analyzes of real-time brain activity. Thirty-one older adults (M = 60 years) completed the PAST. EEG was recorded to assess feedback-related negativity (FRN) and the magnitude of the stress response through autonomic nervous system activity and salivary cortisol. Physiological measures other than EEG included heart rate, respiration rate, heart rate variability, blood pressure and salivary cortisol. These measures were collected at several time points throughout the task. Feedback-related negativity evoked-potential responses were elicited and they significantly differed depending on whether positive or negative feedback was received. The PAST also increased systolic blood pressure, heart rate variability and respiration rates compared to a control condition attentional task. These preliminary results suggest that the PAST is an effective cognitive stressor. Successful measurement of the feedback-related negativity suggests that the PAST is conducive to EEG and time-sensitive ERP experiments. Moreover, the physiological findings support the PAST as a potent method for inducing stress in older adult participants. Further research is needed to confirm these results, but the PAST shows promise as a tool for cognitive stress induction for time-locked event-related potential experiments.

Immobilization of citric acid solutions in portland cement; Imobilizacao de solucoes de acido citrico em cimento Portland

Energy Technology Data Exchange (ETDEWEB)

Lopes, Valdir M.; Rzyski, Barbara M. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

1997-12-01

Decontamination processes by using citric acid on certain items used in the nuclear area, can result in large volumes of liquid wastes with low activity or effluents, contaminated with uranium and some elements dangerous to the environment. A great number of installations that have decontamination processes adopt the zero discharge philosophy. So, one of the forms to isolate the solutions is by reducing its volume through the evaporation process. The generated must can be neutralized and encapsulated or immobilized in Portland cement. This work propose a chemical technique to destroy the citric acid in the decontamination solutions instead of neutralization and, depending on the installation convenience, a direct cement immobilization of these solutions or of the evaporation mud. The results obtained in this work involve data about the workability, setting time and mechanical resistance, after 28 days of sealed cure, for samples with water-cement ratios of 4, 0.5 and 0.6, by weight. (author). 5 refs., 2 tabs.

Diffusion of He in OPC paste and low-heat Portland cement paste containing fly-ash in contact with aqueous phase

International Nuclear Information System (INIS)

Sato, Fuminori; Miwata, Chikanori; Noda, Natsuko; Sato, Seichi; Kozaki, Tamotsu; Higashihara, Tomohiro; Hironaga, Michihiko; Kawanishi, Motoi

2008-01-01

As a part of gas migration studies in concrete package for nuclear waste surrounded by water-saturated rock, the helium diffusion in ordinary Portland cement paste (OPC) was studied using disk form specimen at various water-to-cement (w/c) ratios. The helium diffusion in low-heat Portland cement paste containing fly-ash (LPF) was also studied. Apparent diffusion coefficients of helium in OPC paste were ∼1 x 10 -10 m 2 s -1 at 0.4 w/c ratio, independent of increase of w/c ratio. It is likely that the materials formation such as C-S-H and CH in capillary pores in OPC plays an important role on the helium diffusion rather than porosity increase. Apparent diffusion coefficient of helium in LPF was two orders of magnitude smaller than that in OPC. It is quite possible that the addition of fly-ash contributes to the formation of hydration products which markedly enhance discontinuity of capillary pore. The results of the present study on the two kinds of cement pastes give us valuable information about alternatives to release gas from cement package. (author)

Imaging a fossil oolitic system with GPR, insights into the exposures of the Isle of Portland (UK)

Science.gov (United States)

Moreau, Julien; Hansen, Trine L.; Nielsen, Lars

2015-04-01

The Isle of Portland shows exposure of uppermost Jurassic oolitic carbonate all along its coast. The stone of Portland properties are famous as standards for concrete composition, as building material but also for sculpture. As a consequence, the Isle has been quarried intensively for hundreds of years. The regional exposure quality is very high with a potential 3D control. The site has seen generations of geologist trainees coming for field work. The Wessex Basin where the Isle is sitting contains an active petroleum system and the geologists visiting/training there use the carbonates of Portland as an analogue to equivalent Middle-East oil and gas reservoir. Surprisingly, although the site has a tremendous potential to understand the 3D architecture and the sedimentary dynamic of an oolitic system, only punctual observations of logs (1D), sometimes correlated have been published. Several studies place a shore line between the Isle and the continent striking NEE-SWW and facing towards the Channel. Facies changes are attributed to rapid sea-level variations and Walter's Law. We have collected an extensive GPR survey of the same stratigraphic interval (The Portland Freestone). With a total of 99 GPR profiles, we have produced grids on top of most of the coastal cliffs and quarry faces. We have encountered 3 main architectures: 2-m-high bars with steep clinoforms, 10s of metres-wide channels plugged with a variety of organisms and stacked aggrading bundles of multidirectional dunesets. Our dataset does not illustrate any major unconformity which could be attributed to a sharp sea-level drop. We have interpreted our sedimentary architecture to be the result of various hydrodynamic conditions associated with a mix of wave and tide influences. The Isle shows an island barrier complex which progrades into the basin but also expands laterally filling up the available space and cannibalising itself. More proximal facies are effectively observed in the north of the island

Conceptual design report for immobilized high-level waste interim storage facility (Phase 1)

International Nuclear Information System (INIS)

Burgard, K.C.

1998-01-01

The Hanford Site Canister Storage Building (CSB Bldg. 212H) will be utilized to interim store Phase 1 HLW products. Project W-464, Immobilized High-Level Waste Interim Storage, will procure an onsite transportation system and retrofit the CSB to accommodate the Phase 1 HLW products. The Conceptual Design Report establishes the Project W-464 technical and cost basis

Conceptual design report for immobilized high-level waste interim storage facility (Phase 1)

Energy Technology Data Exchange (ETDEWEB)

Burgard, K.C.

1998-04-09

The Hanford Site Canister Storage Building (CSB Bldg. 212H) will be utilized to interim store Phase 1 HLW products. Project W-464, Immobilized High-Level Waste Interim Storage, will procure an onsite transportation system and retrofit the CSB to accommodate the Phase 1 HLW products. The Conceptual Design Report establishes the Project W-464 technical and cost basis.

Agenda 21 interim balance, 1997

Energy Technology Data Exchange (ETDEWEB)

Van Vuuren, D.P.; Bakkes, J.A.

1997-10-01

Five years after the `United Nations Conference on Environment and Development (UNCED)`, an interim balance was drawn up to see what was done to meet the ambitious challenges adopted in Agenda 21 during this conference. Such a balance is presented in this report and the complementary brochure, `Developments in Sustainability 1992-1997`, reflecting societal developments and changes in environmental quality, as well as changes in responses to environmental concerns. 24 figs., 12 tabs., 68 refs.

Study on Characteristics of Lightweight Aggregate Concrete Made From Foam and Ordinary Portland Cement

Directory of Open Access Journals (Sweden)

Ibrahim N.M.

2016-01-01

Full Text Available The production and characteristic of lightweight bubble aggregates (LBA are presented in this paper. The LBA are produced by mixing between the foam and ordinary Portland cement according to the composition which has been set. Then, the characteristics of LBA such as density, water absorption, specific gravity, compressive strength, aggregate impact value and microscopic analysis of the LBA are analyzed. Those characteristics are identified in order to ensure that the LBA are successfully categorized into lightweight aggregate. The loose bulk density is obtained at 812.5 kg/m3 which can be categorized under lightweight aggregate group. For water absorption the value obtained is 9.7 % which is slightly higher compared to normal aggregate. Meanwhile the average specific gravity obtained for the samples of LBAis 1.75. Compressive strength for the aggregates was 17.76 MPa. The highest compressive strength for LBA foamed concrete was obtained at 25% replacement with 7.83MPa. Thus, the LBA have a significant features and characteristics that can be used as coarse aggregates in concrete.

Análises do comportamento físico de um solo contaminado por borra oleosa ácida e encapsulado com cimento Portland Analyses of physical behavior of a soil contaminated by acidic oily sludge and encapsulated with cement Portland

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José Waldomiro Jiménez Rojas

2008-06-01

Full Text Available Este trabalho tem como objetivo aplicar a técnica de encapsulamento em um solo contaminado com crescentes quantidades do resíduo industrial borra oleosa ácida, utilizando como agente encapsulante o cimento Portland CP-V ARI. A aplicação da técnica de encapsulamento consistiu na realização de estudos pós-tratamento, analisando fisicamente o solo contaminado através de ensaios de resistência à compressão simples e durabilidade. Os resultados apontam que quanto maior a quantidade de borra oleosa ácida presente no solo encapsulado, menor a resistência à compressão simples e maior a perda de massa.The objective of this study is applying the encapsulation technique in soil contaminated with increasing amounts of acidic oily sludge industrial residues, using Portland cement CP-V ARI as the encapsulating agent. The application of the encapsulation technique consisted in the accomplishment of post-treatment studies, analyzing the contaminated soil physically through unconfined compressive strength and durability tests. The results showed that an increasing amount of acidic oily sludge in the encapsulated soil ends up lowering the unconfined compressive strength as well as increasing the mass loss.

THE IMPORTANCE OF FINANCIAL INTERIM REPORTING FOR THE POSITION OF COMPANIES

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Claudia‐Elena\tGRIGORAȘ‐ICHIM

2015-12-01

Full Text Available The importance that each company must grant to the strategic sources of information generates our concern for analysis of the interim financial reporting. In every enterprise, there are doubts on the usefulness of interim financial reports, given the following elements: the necessary time for their preparation (relatively long, their restricted character and the resources necessary to establish them. Finding a common solution to these problems and, implicitly, increasing the interest for interim financial reporting, can help to increase the economic performance of the company, either by reducing the unnecessary costs related to time, or by increasing communication and transparency with third parties. An appropriate management can act early in the direction of counteracting the negative effects in their company or prevention of any commercial or production failures, the overall economic trends in that field and increasing productivity. Starting from these premises, we propose a research in order to capture the main aspects related to the mentioned issues.

Pembuatan dan Pengujian Kualitas Semen Portland Yang Diperkaya Silikat Abu Ampas Tebu

OpenAIRE

Suci Wulandari, Indah Pratama

2015-01-01

Penelitian ini mengkaji pengaruh penambahan abu ampas tebu terhadap kuat tekan mortar dan sifat fisis semen portland komposit, meliputi: kehalusan semen, kebutuhan air semen, waktu pengikatan semen, pemuaian dan komposisi kimia semen. Dari hasil penelitian, besar kuat tekan pada penggunaan abu ampas tebu dengan kadar 9% merupakan penambahan optimum pada mortar yang direndam larutan kapur jenuh Sedangkan dari hasil pengujian fisis yang meliputi kehalusan semen, kebutuhan air semen, waktu pengi...

A Thermoelectric Waste-Heat-Recovery System for Portland Cement Rotary Kilns

Science.gov (United States)

Luo, Qi; Li, Peng; Cai, Lanlan; Zhou, Pingwang; Tang, Di; Zhai, Pengcheng; Zhang, Qingjie

2015-06-01

Portland cement is produced by one of the most energy-intensive industrial processes. Energy consumption in the manufacture of Portland cement is approximately 110-120 kWh ton-1. The cement rotary kiln is the crucial equipment used for cement production. Approximately 10-15% of the energy consumed in production of the cement clinker is directly dissipated into the atmosphere through the external surface of the rotary kiln. Innovative technology for energy conservation is urgently needed by the cement industry. In this paper we propose a novel thermoelectric waste-heat-recovery system to reduce heat losses from cement rotary kilns. This system is configured as an array of thermoelectric generation units arranged longitudinally on a secondary shell coaxial with the rotary kiln. A mathematical model was developed for estimation of the performance of waste heat recovery. Discussions mainly focus on electricity generation and energy saving, taking a Φ4.8 × 72 m cement rotary kiln as an example. Results show that the Bi2Te3-PbTe hybrid thermoelectric waste-heat-recovery system can generate approximately 211 kW electrical power while saving 3283 kW energy. Compared with the kiln without the thermoelectric recovery system, the kiln with the system can recover more than 32.85% of the energy that used to be lost as waste heat through the kiln surface.

Application of dose evaluation of the MCNP code for interim spent fuel cask storage facility

International Nuclear Information System (INIS)

Kosako, Toshiso; Iimoto, Takeshi; Ishikawa, Satoshi; Tsuboi, Takafumi; Teramura, Masahiro; Okamura, Tomomi; Narumiya, Yoshiyuki

2007-01-01

The interim storage facility for spent fuel metallic cask is designed as a concrete building structure with air inlet and outlet for circulating the natural cooling. The feature of the interim storage facility is big capacity of spent fuel at several thousands MTU and restricted site usage. It is important to evaluate realistic dose rate in shielding design of the interim storage facility, therefore the three-dimensional continuous-energy Monte Carlo radiation transport code MCNP that exactly treating the complicated geometry was applied. The validation of dose evaluation for interim storage facility by MCNP code were performed by three kinds of neutron shielding benchmark experiments; cask shadow shielding experiment, duct streaming experiment and concrete deep penetration experiment. Dose rate distributions at each benchmark were measured and compared with the calculated results. The comparison showed a good consistency between calculation and experiment results. (author)

Interim data report for the safety assessment SR-Can

International Nuclear Information System (INIS)

Vahlund, Fredrik; Andersson, Johan

2004-08-01

This document is the interim data report in the project SR-Can. The purpose of the data report is to present input data, with uncertainty estimates, for the SR-Can assessment calculations. Besides input data, the report also describes the standardised procedures used when deriving the input data and the corresponding uncertainty estimates. However, in the present interim version of the report (written in the initial stage of the project when site characterisation has yet not been completed) the standardised procedures have not been possible to apply for most of the data and, in order to present a compilation of the data used in the assessment, much of the input data is presented without following the standardised procedures. This will however be changed for the final version of the SR-Can data report, in order to show the methodology that will be used in the final version one example of how input data will be presented is included (migration data for buffer) . The recommended input data for the assessment calculations are, for the interim version, mainly based on SR 97 Beberg data, these are merely presented without any background or uncertainty discussion (this is presented in the SR 97 data report)

Influence of bismuth oxide concentration on the pH level and biocompatibility of white Portland cement

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Marina Angélica MARCIANO

2014-07-01

Full Text Available Objectives: To investigate if there is a relation between the increase of bismuth oxide and the decrease of pH levels and an intensification of toxicity in the Portland cement. Material and Methods: White Portland cement (WPC was mixed with 0, 15, 20, 30 and 50% bismuth oxide, in weight. For the pH level test, polyethylene tubes were filled with the cements and immersed in Milli-Q water for 15, 30 and 60 days. After each period, the increase of the pH level was assessed. For the biocompatibility, two polyethylene tubes filled with the cements were implanted in ninety albino rats (n=6. The analysis of the intensity of the inflammatory infiltrate was performed after 15, 30 and 60 days. The statistical analysis was performed using the Kruskal-Wallis, Dunn and Friedman tests for the pH level and the Kruskal-Wallis and Dunn tests for the biological analysis (p0.05. For the inflammatory infiltrates, no significant statistical differences were found among the groups in each period (p>0.05. The 15% WPC showed a significant decrease of the inflammatory infiltrate from 15 to 30 and 60 days (p<0.05. Conclusions: The addition of bismuth oxide into Portland cement did not affect the pH level and the biological response. The concentration of 15% of bismuth oxide resulted in significant reduction in inflammatory response in comparison with the other concentrations evaluated.

Low porosity portland cement pastes based on furan polymers

International Nuclear Information System (INIS)

Darweesh, H.H.M.

2005-01-01

The effect of three different types of Furan polymers on the porosity, mechanical properties, mechanism of hydration and microstructure of Ordinary Portland cement (OPC) pastes was investigated. The results showed that mixing the OPC with Furan polymers, the standard water of consistency of the different cement pastes decreases and therefore the setting times (initial and final) are shortened. The total porosity of the hardened cement pastes decreased, while the mechanical properties improved and enhanced at all curing ages of hydration compared with those of the pure OPC pastes. The hydration process with Furan polymers proceeded according to the following decreasing order: F.ac. > F.ph. > F.alc. > OPC

Interim Storage Facility decommissioning. Final report

International Nuclear Information System (INIS)

Johnson, R.P.; Speed, D.L.

1985-01-01

Decontamination and decommissioning of the Interim Storage Facility were completed. Activities included performing a detailed radiation survey of the facility, removing surface and imbedded contamination, excavating and removing the fuel storage cells, restoring the site to natural conditions, and shipping waste to Hanford, Washington, for burial. The project was accomplished on schedule and 30% under budget with no measurable exposure to decommissioning personnel

Biocompatibility and setting time of CPM-MTA and white Portland cement clinker with or without calcium sulfate.

Science.gov (United States)

Bramante, Clovis Monteiro; Kato, Marcia Magro; Assis, Gerson Francisco de; Duarte, Marco Antonio Hungaro; Bernardineli, Norberti; Moraes, Ivaldo Gomes de; Garcia, Roberto Brandão; Ordinola-Zapata, Ronald; Bramante, Alexandre Silva

2013-01-01

To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM. Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey's test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level. Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s). All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinker.

Terrestrial gravity data analysis for interim gravity model improvement

Science.gov (United States)

1987-01-01

This is the first status report for the Interim Gravity Model research effort that was started on June 30, 1986. The basic theme of this study is to develop appropriate models and adjustment procedures for estimating potential coefficients from terrestrial gravity data. The plan is to use the latest gravity data sets to produce coefficient estimates as well as to provide normal equations to NASA for use in the TOPEX/POSEIDON gravity field modeling program.

Single-shell tank interim stabilization project plan

Energy Technology Data Exchange (ETDEWEB)

Ross, W.E.

1998-05-11

This project plan establishes the management framework for conduct of the TWRS Single-Shell Tank Interim Stabilization completion program. Specifically, this plan defines the mission needs and requirements; technical objectives and approach; organizational structure, roles, responsibilities, and interfaces; and operational methods. This plan serves as the project executional baseline.

14 CFR 136.41 - Interim operating authority.

Science.gov (United States)

2010-01-01

... AND NATIONAL PARKS AIR TOUR MANAGEMENT National Parks Air Tour Management § 136.41 Interim operating... terminate 180 days after the date on which an air tour management plan is established for the park and tribal lands; (6) Shall promote protection of national park resources, visitor experiences, and tribal...

Alternatives for managing wastes from reactors and post-fission operations in the LWR fuel cycle. Volume 3. Alternatives for interim storage and transportation

International Nuclear Information System (INIS)

1976-05-01

Volume III of the five-volume report contains information on alternatives for interim storage and transportation. Section titles are: interim storage of spent fuel elements; interim storage of chop-leach fuel bundle residues; tank storage of high-level liquid waste; interim storage of solid non-high-level wastes; interim storage of solidified high-level waste; and, transportation alternatives

Prognostic value of interim FDG-PET in Hodgkin lymphoma : systematic review and meta-analysis

NARCIS (Netherlands)

Adams, Hugo J A; Nievelstein, Rutger A J; Kwee, Thomas C.

2015-01-01

This study aimed to systematically review and meta-analyse the value of interim (18) F-fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET) in predicting treatment failure in Hodgkin lymphoma. MEDLINE was systematically searched for original studies that used standardized international

PROJECT W-551 INTERIM PRETREATMENT SYSTEM TECHNOLOGY SELECTION SUMMARY DECISION REPORT AND RECOMMENDATION

International Nuclear Information System (INIS)

CONRAD EA

2008-01-01

This report provides the conclusions of the tank farm interim pretreatment technology decision process. It documents the methodology, data, and results of the selection of cross-flow filtration and ion exchange technologies for implementation in project W-551, Interim Pretreatment System. This selection resulted from the evaluation of specific scope criteria using quantitative and qualitative analyses, group workshops, and technical expert personnel

Rosiglitazone evaluated for cardiovascular outcomes--an interim analysis

DEFF Research Database (Denmark)

Home, Philip D; Pocock, Stuart J; Beck-Nielsen, Henning

2007-01-01

BACKGROUND: A recent meta-analysis raised concern regarding an increased risk of myocardial infarction and death from cardiovascular causes associated with rosiglitazone treatment of type 2 diabetes. METHODS: We conducted an unplanned interim analysis of a randomized, multicenter, open...... group). The primary end point was hospitalization or death from cardiovascular causes. RESULTS: Because the mean follow-up was only 3.75 years, our interim analysis had limited statistical power to detect treatment differences. A total of 217 patients in the rosiglitazone group and 202 patients...... in the control group had the adjudicated primary end point (hazard ratio, 1.08; 95% confidence interval [CI], 0.89 to 1.31). After the inclusion of end points pending adjudication, the hazard ratio was 1.11 (95% CI, 0.93 to 1.32). There were no statistically significant differences between the rosiglitazone...

Elementary characterization of samples of Portland cement, natural gypsum and phosphogypsum mortars from Brazil

Energy Technology Data Exchange (ETDEWEB)

Narloch, Danielle Cristine; Paschuk, Sergei Anatolyevich; Corrêa, Janine Nicolosi; Torres, Catarina Alzira Peddis; Mazer, Wellington; Macioski, Gustavo [Universidade Tecnologica Federal do Parana (UTFPR), PR (Brazil); Lara, Alessandro [Universidade de Sao Paulo (USP), SP (Brazil). Departamento de Fisica; Casali, Juliana Machado, E-mail: janine_nicolosi@hotmail.com, E-mail: alellara@hotmail.com, E-mail: jucasali@gmail.com [Instituto Federal de Santa Catarina (IFSC), Florianópolis, SC (Brazil)

2017-07-01

Portland cement, the basic ingredient of concrete and is manufactured by crushing, milling and proportioning limestone, sand, clay, iron ore and secondary materials such as shells, chalk or marl combined with shale slate or blast furnace slag, fly ash, gypsum, phosphogypsum, and some others. Evaluating the physical and mineralogical characteristics of the cement and its chemical composition is essential to establish the quality of the product. Therefore, the objective of this work was to characterize and quantify the most common chemical elements in the samples of Brazilian Portland cement, natural gypsum, and phosphogypsum mortars by means of X-ray dispersive energy spectroscopy (EDXRF), as well as to evaluate the strength of these mortars. For analysis of the compressive strength, initially prepared samples were submitted to a destructive mechanical test. Subsequently samples were milled and compacted to form thin tablets, which were submitted to the EDXRF analysis. The qualitative and quantitative analyzes showed that for phosphogypsum mortar the largest mass fractions were found of 49.8±2.5% (Si), 24.66±0.96% (S) and 22.10±0.42% (Ca). For gypsum mortar those values were found of 43.41±0.45% (Ca), 33.8 ± 0.8% (S) and 18.9±1.2% (Si), respectively; and for Portland cement mortar, the predominant elements in those samples have the mass fractions of 64.20±0.52% (Ca) and 27.3±1.5% (Si). The results showed that obtained values of mass fraction of the elements Si, S, K, Ca, Ti, Fe are in rather good agreement with quantities indicated for manufacture. Besides, gypsum and phosphogypsum presented almost the same composition and compressive strength. (author)

Elementary characterization of samples of Portland cement, natural gypsum and phosphogypsum mortars from Brazil

International Nuclear Information System (INIS)

Narloch, Danielle Cristine; Paschuk, Sergei Anatolyevich; Corrêa, Janine Nicolosi; Torres, Catarina Alzira Peddis; Mazer, Wellington; Macioski, Gustavo; Lara, Alessandro

2017-01-01

Portland cement, the basic ingredient of concrete and is manufactured by crushing, milling and proportioning limestone, sand, clay, iron ore and secondary materials such as shells, chalk or marl combined with shale slate or blast furnace slag, fly ash, gypsum, phosphogypsum, and some others. Evaluating the physical and mineralogical characteristics of the cement and its chemical composition is essential to establish the quality of the product. Therefore, the objective of this work was to characterize and quantify the most common chemical elements in the samples of Brazilian Portland cement, natural gypsum, and phosphogypsum mortars by means of X-ray dispersive energy spectroscopy (EDXRF), as well as to evaluate the strength of these mortars. For analysis of the compressive strength, initially prepared samples were submitted to a destructive mechanical test. Subsequently samples were milled and compacted to form thin tablets, which were submitted to the EDXRF analysis. The qualitative and quantitative analyzes showed that for phosphogypsum mortar the largest mass fractions were found of 49.8±2.5% (Si), 24.66±0.96% (S) and 22.10±0.42% (Ca). For gypsum mortar those values were found of 43.41±0.45% (Ca), 33.8 ± 0.8% (S) and 18.9±1.2% (Si), respectively; and for Portland cement mortar, the predominant elements in those samples have the mass fractions of 64.20±0.52% (Ca) and 27.3±1.5% (Si). The results showed that obtained values of mass fraction of the elements Si, S, K, Ca, Ti, Fe are in rather good agreement with quantities indicated for manufacture. Besides, gypsum and phosphogypsum presented almost the same composition and compressive strength. (author)

75 FR 13484 - Foreign-Trade Zone 22; Temporary/Interim Manufacturing Authority; LG Electronics Mobilecomm USA...

Science.gov (United States)

2010-03-22

... DEPARTMENT OF COMMERCE [Docket T-1-2010] Foreign-Trade Zones Board Foreign-Trade Zone 22; Temporary/Interim Manufacturing Authority; LG Electronics Mobilecomm USA, Inc. (Cell Phones); Notice of.../ interim manufacturing (T/IM) authority, on behalf of LG Electronics Mobilecomm USA, Inc. (LGEMU), to...

Interim Action Proposed Plan for the Chemicals, Metals, and Pesticides (CMP) Pits Operable Unit; FINAL

International Nuclear Information System (INIS)

Bradley, J.

2002-01-01

The purpose of this Interim Action Proposed Plan (IAPP) is to describe the preferred interim remedial action for addressing the Chemicals, Metals, and Pesticides (CMP) Pits Operable Unit and to provide an opportunity for public input into the remedial action selection process

Effect of addition of opaline siliceous rocks at different proportions to portland cement

Directory of Open Access Journals (Sweden)

de Luxan, M. P.

1989-03-01

Full Text Available En este trabajo se estudia la influencia de la presencia de rocas silíceas opalinas, procedentes de las provincias de Salamanca, Zamora y Avila, en las propiedades de los cementos mixtos fabricados con cemento portland y proporciones variables de estas rocas utilizadas como adiciones activas. La caracterización de estos materiales y el estudio de las propiedades de los cementos preparados revelan la capacidad puzolánica de las rocas opalinas, y su singularidad respecto a otras puzolanas naturales, así como su posibilidad de empleo en la fabricación de cementos con adiciones.

En este trabajo se estudia la influencia de la presencia de rocas silíceas opalinas, procedentes de las provincias de Salamanca, Zamora y Avila, en las propiedades de los cementos mixtos fabricados con cemento portland y proporciones variables de estas rocas utilizadas como adiciones activas. La caracterización de estos materiales y el estudio de las propiedades de los cementos preparados revelan la capacidad puzolánica de las rocas opalinas, y su singularidad respecto a otras puzolanas naturales, así como su posibilidad de empleo en la fabricación de cementos con adiciones.

Food mirages: geographic and economic barriers to healthful food access in Portland, Oregon.

Science.gov (United States)

Breyer, Betsy; Voss-Andreae, Adriana

2013-11-01

This paper investigated the role of grocery store prices in structuring food access for low-income households in Portland, Oregon. We conducted a detailed healthful foods market basket survey and developed an index of store cost based on the USDA Thrifty Food Plan. Using this index, we estimated the difference in street-network distance between the nearest low-cost grocery store and the nearest grocery store irrespective of cost. Spatial regression of this metric in relation to income, poverty, and gentrification at the census tract scale lead to a new theory regarding food access in the urban landscape. Food deserts are sparse in Portland, but food mirages are abundant, particularly in gentrifying areas where poverty remains high. In a food mirage, grocery stores are plentiful but prices are beyond the means of low-income households, making them functionally equivalent to food deserts in that a long journey to obtain affordable, nutritious food is required in either case. Results suggested that evaluation of food environments should, at a minimum, consider both proximity and price in assessing healthy food access for low-income households. © 2013 Elsevier Ltd. All rights reserved.

Automotive Mechanics Occupational Performance Survey. Interim Report.

Science.gov (United States)

Borcher, Sidney D.; Leiter, Paul B.

The purpose of this federally-funded interim report is to present the results of a task inventory analysis survey of automotive mechanics completed by project staff within the Instructional Systems Design Program at the Center for Vocational and Technical Education. Intended for use in curriculum development for vocational education programs in…

340 waste handling facility interim safety basis

Energy Technology Data Exchange (ETDEWEB)

VAIL, T.S.

1999-04-01

This document presents an interim safety basis for the 340 Waste Handling Facility classifying the 340 Facility as a Hazard Category 3 facility. The hazard analysis quantifies the operating safety envelop for this facility and demonstrates that the facility can be operated without a significant threat to onsite or offsite people.

340 waste handling facility interim safety basis

International Nuclear Information System (INIS)

VAIL, T.S.

1999-01-01

This document presents an interim safety basis for the 340 Waste Handling Facility classifying the 340 Facility as a Hazard Category 3 facility. The hazard analysis quantifies the operating safety envelop for this facility and demonstrates that the facility can be operated without a significant threat to onsite or offsite people

Radiation shielding and dose rate evaluation at the interim storage facility for spent fuel from Cernavoda NPP

International Nuclear Information System (INIS)

Stanciu, Marcela; Mateescu, Silvia; Pantazi, Doina; Penescu, Maria

2000-01-01

At present studies necessary to license the Interim Storage Facility for the Spent Fuel (CANDU type) from Cernavoda NPP are developed in our country.The spent fuel from Cernavoda NPP is discharged into Spent Fuel Bay in Service Building of the plant, where it remains several years for cooling. After this period, the bundles of spent fuel are to be transferred to the Interim Storage Facility.The dry interim storage solution seems to be the most appropriate variant for Cernavoda NPP.The design of the Spent Fuel Interim Storage Facility must meet the applicable safety requirements in order to ensure radiological protection of the personnel, public and environment during all phases of the facility achievement. In this paper we intend to present the calculation of radiation shielding at the spent fuel interim storage facility for two technical solutions: - Concrete Monolithic Module and Concrete Storage Cask. In order to quantify the fuel composition after irradiation, the isotope generation and depletion code ORIGEN 2.1 has been used, taking into account a cooling time of 7 years and 9 years, respectively, for these two variants. The shielding calculations have been performed using the computer codes QAD-5K and MICROSHIELD-4. The evaluations refer only to gamma radiation because the resulting neutron source (from (α,n) reactions and spontaneous fission) is insignificant as compared to the gamma source. The final results consist in the minimum thickness of the shielding and the corresponding external dose rates, ensuring a design average dose rate based on national and international regulations. (authors)

Evolution and quantification of the main Sensitisers in commercial portland cements

Directory of Open Access Journals (Sweden)

Frías, M.

2002-03-01

Full Text Available The commercial Portland cements contain minor elements in their chemical compositions. The presence of these elements has a direct incidence in different aspects: rheological behaviour, reaction kinetics, environmental, etc. Some of them also have a negative effect on the human health; so, chromium (Cr, nickel (Ni and cobalt (Co are the main allergens present in Portland cements, causing of Professional Dermatitis in construction workers. The current study is focussed on the quantification of total and soluble chromium, nickel and cobalt in a wide range of Spanish commercial cements. These values can represent a contribution to the establishing of possible limitations or reductions of these elements in forthcoming standards. Analytical data show that clinkers are the main responsibles of the presence of soluble chromium in commercial cements. This fact could be indicating that chromium solubility (from inert Cr III to soluble Cr VI would be closely related to the clinkerisation conditions. On the other hand, there is not a direct ratio between total chromium and soluble chromium; it means that analytical results are punctual and not any case can be extrapolating ones. Ni and Co solubility in water is practically negligible either raw as clinkers.

Los cementos Portland comerciales contienen elementos minoritarios en su composición química. La presencia de estos elementos tiene una incidencia directa en diferentes aspectos: comportamiento reológico, cinética de reacción, contaminación ambiental, etc. Algunos de ellos, aparte de su incidencia mencionada anteriormente, tienen un efecto negativo en la salud humana. Así, el cromo (Cr, níquel (Ni y cobalto (Co son los principales alérgenos contenidos en los cementos y, por lo tanto, los principales causantes de la Dermatitis Profesional. Este trabajo se centra en la cuantifîcación de los contenidos totales y solubles de cromo, níquel y cobalto presentes en los cementos comerciales

Surface Water Interim Measures/Interim Remedial Action Plan/Environmental Assessment and Decision Document for South Walnut Creek Basin (Operable Unit No. 2)

International Nuclear Information System (INIS)

1991-01-01

The Department of Energy (DOE) is pursuing an Interim Measure/Interim Remedial Action (IM/IRA) at the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2) at the Rocky Flats Plant (RFP). This IM/IRA is to be conducted to minimize the release from these areas of hazardous substances that pose a potential threat to the public health and environment. The Plan involved the collection of contaminated surface water at specific locations, treatment by chemical precipitation, cross-flow membrane filtration and granular activated carbon (GAC) adsorption, and surface discharge of treated water. Information for the initial configuration of the Plan is presented in the document entitled ''Proposed Interim Measures/Interim Remedial Action Plan and Decision Document, 903 Pad, Mound, and East Trenches Areas, Operable Unit No. 2'' (IM/IRAP) dated 26 September 1990. Information concerning the proposed Surface Water IM/IRA was presented during a public meeting held from 7 to 10 p.m., Tuesday, 23 October 1990, at the Westminster City Park Recreation Center in Westminster, Colorado. This Responsiveness Summary presents DOE's response to all comments received at the public meeting, as well as those mailed to DOE during the public comment period which ended 24 November 1990. There were a number of technical comments on the plan that DOE has addressed herein. It is noted that several major issues were raised by the comments. Regardless of the estimated low risk to the public from construction and water transport activities, the popular sentiment of the public, based on comments received, is strong concern over worker and public health risks from these activities. In the light of public and municipal concerns, DOE proposes to eliminate from this IM/IRA the interbasin transfer of Woman Creek seepage to the South Walnut Creek drainage and to address collection and treatment of contaminated South Walnut Creek and Woman Creek surface water under two separate IM/IRAs

In Vitro Bioactivity and Setting Times of White Portland Cement Combined with Different Radio Pacifying Agents

Directory of Open Access Journals (Sweden)

Coleman Nichola Jayne

2017-01-01

Full Text Available Commercial formulations based on 80:20 mixtures of Portland cement and bismuth oxide (a radiopacifying agent are used in dentistry as root-filling materials. This study compares the impact of two alternative radiopacifiers, barium sulphate and zirconium oxide, with that of bismuth oxide, on the setting times and bioactivity of white Portland cement. The findings indicate that bismuth oxide prolongs both the initial and final setting times of the cement, and that barium sulphate and zirconium oxide have no effect on this parameter. Hydroxyapatite (HA formed on the surfaces of all test samples within 7 days of exposure to simulated body fluid, indicating that they possess the potential to stimulate new hard tissue formation. Fourier transform infrared spectroscopy, the traditional technique for the identification of HA, was not appropriate for the analysis of these cement systems owing to the overlap of signals from each of the radiopacifiers with the characteristic P-O bending modes of HA in the 570 – 610 cm−1 region. In this respect, the P-O band at 965 cm−1 of HA in the Raman spectrum was found to be a suitable means of detection since it is discrete with respect to all signals arising from the radiopacifying agents and cement phases.

Evaluation of bacterial leakage of four root- end filling materials: Gray Pro Root MTA, White Pro Root MTA, Root MTA and Portland Cement (type I

Directory of Open Access Journals (Sweden)

Zarabian M.

2005-07-01

Full Text Available Background and Aim: Today several materials have been used for root- end filling in endodontic surgery. Optimal properties of Pro Root MTA in in-vitro and in-vivo studies has been proven. On the other hand, based on some studies, Root MTA (Iranian Pro Root MTA and Portland cement are similar to Pro Root MTA in physical and biologic properties. The aim of this study was to evaluate bacterial leakage (amount and mean leakage time of four root- end filling materials. Materials and Methods: In this experimental in-vitro study, seventy six extracted single- rooted human teeth were randomly divided into six groups for root-end filling with gray Pro Root MTA, white Pro Root MTA, Root MTA (Iranian Pro Root MTA, Portland Cement (type I and positive and negative control groups. Root canals were instrumented using the step- back technique. Root- end filling materials were placed in 3mm ultra sonic retro preparations. Samples and microleakage model system were sterilized in autoclave. The apical 3-4 mm of the roots were immersed in phenol red with 3% lactose broth culture medium. The coronal access of each specimen was inoculated every 24h with a suspension of Streptococcus sanguis (ATCC 10556. Culture media were observed every 24h for colour change indicating bacterial contamination for 60 days. Statistical analysis was performed using log- rank test with P<0.05 as the limit of significance. Results: At the end of study 50%, 56.25%, 56.25% and 50% of specimens filled with Gray Pro Root MTA, White Pro Root MTA. Root MTA and Portland Cement (type I had evidence of leakage respectively. The mean leakage time was 37.19±6.29, 36.44±5.81, 37.69±5.97 and 34.81±6.67 days respectively. Statistical analysis of data showed no significant difference among the leakage (amount and mean leakage time of the four tested root- end filling materials (P=0.9958. Conclusion: Based on the results of this study, there were no significant differences in leakage among the four

Finding of no significant impact. Consolidation and interim storage of special nuclear material at Rocky Flats Environmental Technology Site

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-06-01

The Department of Energy (DOE) has prepared an environmental assessment (EA), DOE/EA -- 1060, for the consolidation, processing, and interim storage of Category I and II special nuclear material (SNM) in Building 371 at the Rocky Flats Environmental Technology Site (hereinafter referred to as Rocky Flats or Site), Golden, Colorado. The scope of the EA included alternatives for interim storage including the no action alternative, the construction of a new facility for interim storage at Rocky Flats, and shipment to other DOE facilities for interim storage.

Finding of no significant impact. Consolidation and interim storage of special nuclear material at Rocky Flats Environmental Technology Site

International Nuclear Information System (INIS)

1995-06-01

The Department of Energy (DOE) has prepared an environmental assessment (EA), DOE/EA -- 1060, for the consolidation, processing, and interim storage of Category I and II special nuclear material (SNM) in Building 371 at the Rocky Flats Environmental Technology Site (hereinafter referred to as Rocky Flats or Site), Golden, Colorado. The scope of the EA included alternatives for interim storage including the no action alternative, the construction of a new facility for interim storage at Rocky Flats, and shipment to other DOE facilities for interim storage

78 FR 70244 - Electronic Interim Assistance Reimbursement Program

Science.gov (United States)

2013-11-25

..., Social Security Online, at http://www.socialsecurity.gov . SUPPLEMENTARY INFORMATION: Background To be... SOCIAL SECURITY ADMINISTRATION 20 CFR Part 416 [Docket No. SSA-2011-0104] RIN 0960-AH45 Electronic Interim Assistance Reimbursement Program AGENCY: Social Security Administration. ACTION: Notice of...

Application of NUREG/CR-5999 interim fatigue curves to selected nuclear power plant components

International Nuclear Information System (INIS)

Ware, A.G.; Morton, D.K.; Nitzel, M.E.

1995-03-01

Recent test data indicate that the effects of the light water reactor (LWR) environment could significantly reduce the fatigue resistance of materials used in the reactor coolant pressure boundary components of operating nuclear power plants. Argonne National Laboratory has developed interim fatigue curves based on test data simulating LWR conditions, and published them in NUREG/CR-5999. In order to assess the significance of these interim fatigue curves, fatigue evaluations of a sample of the components in the reactor coolant pressure boundary of LWRs were performed. The sample consists of components from facilities designed by each of the four U.S. nuclear steam supply system vendors. For each facility, six locations were studied, including two locations on the reactor pressure vessel. In addition, there are older vintage plants where components of the reactor coolant pressure boundary were designed to codes that did not require an explicit fatigue analysis of the components. In order to assess the fatigue resistance of the older vintage plants, an evaluation was also conducted on selected components of three of these plants. This report discusses the insights gained from the application of the interim fatigue curves to components of seven operating nuclear power plants

Federal Administrative Court confirms interim action for the Kruemmel power plant site

International Nuclear Information System (INIS)

Anon.

1982-01-01

The interim action concerning the reactor site was confirmed in 1972, the action of voidance because of the possible injuriousness to health was rejected in the first instance. In the appeal OVG Lueneburg had sharpened three clauses concerning the contents of the restrictions and injunctions included in the interim action to the disadvantage of the operator. Responding to a new appeal the BVerwG has eliminated these restrictions and dismissed the following appeals of the plaintiffs. (HP) [de

77 FR 34935 - Foreign-Trade Zone 161; Temporary/Interim Manufacturing Authority; Siemens Energy, Inc., (Wind...

Science.gov (United States)

2012-06-12

... DEPARTMENT OF COMMERCE Foreign-Trade Zones Board [Docket T-4-2012] Foreign-Trade Zone 161; Temporary/Interim Manufacturing Authority; Siemens Energy, Inc., (Wind Turbine Nacelles and Hubs); Notice of... temporary/interim manufacturing (T/IM) authority, on behalf of Siemens Energy, Inc., to manufacture wind...

Resistência à compressão do solo-cimento com substituição parcial do cimento Portland por resíduo cerâmico moído Compressive strength of soil-cement with partial replacement of the Portland cement by crushed ceramic waste

Directory of Open Access Journals (Sweden)

Rivanildo Dallacort

2002-12-01

Full Text Available Neste trabalho, apresenta-se o estudo experimental da resistência à compressão do solo-cimento, com substituição parcial do cimento Portland por resíduo cerâmico moído. Para tanto, foram ensaiados 81 espécimenes cilíndricos desse material à compressão, em que parte do cimento foi substituída por material cerâmico moído. Realizou-se uma programação fatorial, na qual três variáveis foram selecionadas para estudo: o teor de material ligante (cimento + resíduo cerâmico, a umidade do solo e o teor de resíduo cerâmico adicionado. É apresentado um estudo estatístico através de análise de variância da massa específica do material e da resistência a compressão. Tal estudo permitiu concluir-se que substituições de 25 e 57% do teor de cimento por material cerâmico podem produzir blocos de solo-cimento com resistências superiores a 2 MPa, com teor de material ligante de 6 e 8%, respectivamente.In this paper, an experimental study of the compressive strength of soil-cement with partial replacement of the Portland cement by crushed ceramic waste is presented and discussed. For this, eighty-one cylindrical specimens of soil-cement were tested, where part of cement percentage was replaced by crushed ceramic waste. The experiment was conducted in factorial design and three variables were selected and studied: the binding material content (cement + ceramic waste, soil moisture content and the ratio of ceramic waste. A statistical study using variance analysis of the specific mass and compressive strength of the material is presented. This study concluded that replacement ratios of 25 and 57% of the Portland cement by crushed ceramic material can be used to fabricate soil-cement bricks with strength higher than 2 MPa, for a binding material content of 6 and 8% respectively.

Using ERA-Interim reanalysis for creating datasets of energy-relevant climate variables

Science.gov (United States)

Jones, Philip D.; Harpham, Colin; Troccoli, Alberto; Gschwind, Benoit; Ranchin, Thierry; Wald, Lucien; Goodess, Clare M.; Dorling, Stephen

2017-07-01

The construction of a bias-adjusted dataset of climate variables at the near surface using ERA-Interim reanalysis is presented. A number of different, variable-dependent, bias-adjustment approaches have been proposed. Here we modify the parameters of different distributions (depending on the variable), adjusting ERA-Interim based on gridded station or direct station observations. The variables are air temperature, dewpoint temperature, precipitation (daily only), solar radiation, wind speed, and relative humidity. These are available on either 3 or 6 h timescales over the period 1979-2016. The resulting bias-adjusted dataset is available through the Climate Data Store (CDS) of the Copernicus Climate Change Data Store (C3S) and can be accessed at present from climate.copernicus.eu" target="_blank">ftp://ecem.climate.copernicus.eu. The benefit of performing bias adjustment is demonstrated by comparing initial and bias-adjusted ERA-Interim data against gridded observational fields.

EPA's Revised Interim Financial Assistance Conflict of Interest Policy

Science.gov (United States)

EPA has established the following revised interim policy governing disclosure of actual and potential conflicts of interest (COI Policy) by applicants for, and recipients of, federal financial assistance awards from EPA.

Data Analysis of GPM Constellation Satellites-IMERG and ERA-Interim precipitation products over West of Iran

Science.gov (United States)

Sharifi, Ehsan; Steinacker, Reinhold; Saghafian, Bahram

2016-04-01

Precipitation is a critical component of the Earth's hydrological cycle. The primary requirement in precipitation measurement is to know where and how much precipitation is falling at any given time. Especially in data sparse regions with insufficient radar coverage, satellite information can provide a spatial and temporal context. Nonetheless, evaluation of satellite precipitation is essential prior to operational use. This is why many previous studies are devoted to the validation of satellite estimation. Accurate quantitative precipitation estimation over mountainous basins is of great importance because of their susceptibility to hazards. In situ observations over mountainous areas are mostly limited, but currently available satellite precipitation products can potentially provide the precipitation estimation needed for meteorological and hydrological applications. One of the newest and blended methods that use multi-satellites and multi-sensors has been developed for estimating global precipitation. The considered data set known as Integrated Multi-satellitE Retrievals (IMERG) for GPM (Global Precipitation Measurement) is routinely produced by the GPM constellation satellites. Moreover, recent efforts have been put into the improvement of the precipitation products derived from reanalysis systems, which has led to significant progress. One of the best and a worldwide used model is developed by the European Centre for Medium Range Weather Forecasts (ECMWF). They have produced global reanalysis daily precipitation, known as ERA-Interim. This study has evaluated one year of precipitation data from the GPM-IMERG and ERA-Interim reanalysis daily time series over West of Iran. IMERG and ERA-Interim yield underestimate the observed values while IMERG underestimated slightly and performed better when precipitation is greater than 10mm. Furthermore, with respect to evaluation of probability of detection (POD), threat score (TS), false alarm ratio (FAR) and probability

The origins of American industrial success: Evidence from the US portland cement industry

OpenAIRE

Prentice, David

2008-01-01

The contributions of innovations, factor endowments and institutions to American industrialization are examined through analysing the rise of the American portland cement industry. Minerals abundance contributed in multiple ways to the spectacular rise of the industry from the 1890s. However, the results of a structural econometric analysis of entry suggests geological surveys, institutions highlighted by David and Wright, played a contributing rather than critical rol...

39 CFR 211.4 - Interim personnel regulations.

Science.gov (United States)

2010-07-01

... 39 Postal Service 1 2010-07-01 2010-07-01 false Interim personnel regulations. 211.4 Section 211.4... under the Postal Reorganization Act. (b) Continuation of Personnel Provisions of Former title 39, U.S.C... collective bargaining agreement under the Postal Reorganization Act, all provisions of former title 39, U.S.C...

Arsenic content in Portland cement: a literature review.

Science.gov (United States)

Tenório de Franca, Talita Ribeiro; da Silva, Raphaela Juvenal; Sedycias de Queiroz, Michellini; Aguiar, Carlos Menezes

2010-01-01

Portland cement (PC) is a hydraulic binding material widely used in the building industry. The main interest in its use in dentistry is focused on a possible alternative to mineral trioxide aggregate (MTA) because PC is less expensive and is widely available. In dentistry, PC has been used in dental procedures such as pulpotomy, pulp capping, repair of root perforation and root-end filling. The purpose of this article is review the dental literature about the PC, its composition with special attention to arsenic content, properties, and application in dentistry. A bibliographic research was performed in Bireme, PubMed, LILACS and Scopus data bases looking for national and international studies about the PC composition, properties and clinical use. It was observed that PC has favorable biological properties very similar to those of MTA. The PC has shown good cell proliferation induction with formation of a monolayer cell, satisfactory inflammatory response, inhibitory effect of prostaglandin and antimicrobial effect. Studies have shown that PC is not cytotoxic, stimulates the apposition of reparative dentin and permits cellular attachment and growth. Regarding arsenic presence, its levels and release are low. PC has physical, chemical and biological properties similar to MTA. Arsenic levels and release are low, therefore, unable to cause toxic effects.

Arsenic content in Portland cement: A literature review

Directory of Open Access Journals (Sweden)

Tenorio de Franca Talita

2010-01-01

Full Text Available Portland cement (PC is a hydraulic binding material widely used in the building industry. The main interest in its use in dentistry is focused on a possible alternative to mineral trioxide aggregate (MTA because PC is less expensive and is widely available. In dentistry, PC has been used in dental procedures such as pulpotomy, pulp capping, repair of root perforation and root-end filling. The purpose of this article is review the dental literature about the PC, its composition with special attention to arsenic content, properties, and application in dentistry. A bibliographic research was performed in Bireme, PubMed, LILACS and Scopus data bases looking for national and international studies about the PC composition, properties and clinical use. It was observed that PC has favorable biological properties very similar to those of MTA. The PC has shown good cell proliferation induction with formation of a monolayer cell, satisfactory inflammatory response, inhibitory effect of prostaglandin and antimicrobial effect. Studies have shown that PC is not cytotoxic, stimulates the apposition of reparative dentin and permits cellular attachment and growth. Regarding arsenic presence, its levels and release are low. PC has physical, chemical and biological properties similar to MTA. Arsenic levels and release are low, therefore, unable to cause toxic effects.

Dry interim storage of radioactive material in Germany

International Nuclear Information System (INIS)

Drobniewski, Christian; Palmes, Julia

2013-01-01

In accordance with the waste management concept in Germany, spent fuel is stored in interim storage facilities for a period of up to 40 years until deposition in a geological repository. In twelve on-site interim storages in the vicinity or directly on the sites of the nuclear power plants, spent fuel elements from reactor operation are stored after the necessary period of decay in wet storage basins inside the reactors. Additionally, three central interim storage facilities for storage of spent fuel of different origin are in operation. The German facilities realize the concept of dry interim storage in metallic transport and storage casks. The confinement of the radioactive material is ensured by the double lid system of the casks, of which the leak tightness is monitored constantly. The casks are constructed to provide adequate heat removal and shielding of gamma and neutron radiation. Usually the storage facilities are halls of thick concrete structures, which ensure the removal of the decay heat by natural convection. The main safety goal of the storage concept is to prevent unnecessary exposure of persons, material goods and environment to ionizing radiation. Moreover any exposure should be kept as low as reasonable achievable. To reach this goal the containment of the radioactive materials, the disposal of decay heat, the sub criticality and the shielding of ionizing radiation has to be demonstrated by the applicant and verified by the licensing authority. In particular accidents, incidents and disasters have to be considered in the facility and cask design. This includes mechanical impacts onto the cask, internal and external fire, and environmental effects like wind, rain, snowfall, flood, earthquakes and landslides. In addition civilizatoric influences like plane crashes and explosions have to be taken into account. In all mentioned cases the secure confinement of the radioactive materials has to be ensured. On-site storage facilities have to consider the

Guidelines for interim storage of low level waste

International Nuclear Information System (INIS)

Hornibrook, C.; Castagnacci, A.; Clymer, G.; Kelly, J.; Naughton, M.; Saunders, P.; Stoner, P.; Walker, N.; Cazzolli, R.; Dettenmeier, R.; Loucks, L.; Rigsby, M.; Spall, M.; Strum, M.

1992-12-01

This report presents an overview of on-site storage of Low Level Waste while providing guidelines for using the complete Interim On-Site Storage of Low Level Waste report series. Overall, this report provides a methodology for planning and implementing on-site storage

A study of the usage of LPAs by the North Carolina Division of Motor Vehicles : interim report - phase I.

Science.gov (United States)

2014-02-27

This interim report was prepared to assist NCDMV in meeting the requirements of S.B. 402, Sec. 34.17, which mandates that NCDOT in collaboration with NCDMV shall evaluate current contractual models and compensation for license plate agency (LPA...

The Homestake Interim Laboratory and Homestake DUSEL

Science.gov (United States)

Lesko, Kevin T.

2011-12-01

The former Homestake gold mine in Lead South Dakota is proposed for the National Science Foundation's Deep Underground Science and Engineering Laboratory (DUSEL). The gold mine provides expedient access to depths in excess of 8000 feet below the surface (>7000 mwe). Homestake's long history of promoting scientific endeavours includes the Davis Solar Neutrino Experiment, a chlorine-based experiment that was hosted at the 4850 Level for more than 30 years. As DUSEL, Homestake would be uncompromised by competition with mining interests or other shared uses. The facility's 600-km of drifts would be available for conversion for scientific and educational uses. The State of South Dakota, under Governor Rounds' leadership, has demonstrated exceptionally strong support for Homestake and the creation of DUSEL. The State has provided funding totalling $46M for the preservation of the site for DUSEL and for the conversion and operation of the Homestake Interim Laboratory. Motivated by the strong educational and outreach potential of Homestake, the State contracted a Conversion Plan by world-recognized mine-engineering contractor to define the process of rehabilitating the facility, establishing the appropriate safety program, and regaining access to the facility. The State of South Dakota has established the South Dakota Science and Technology Authority to oversee the transfer of the Homestake property to the State and the rehabilitation and preservation of the facility. The Homestake Scientific Collaboration and the State of South Dakota's Science and Technology Authority has called for Letters of Interest from scientific, educational and engineering collaborations and institutions that are interested in hosting experiments and uses in the Homestake Interim Facility in advance of the NSF's DUSEL, to define experiments starting as early as 2007. The Homestake Program Advisory Committee has reviewed these Letters and their initial report has been released. Options for

The Homestake Interim Laboratory and Homestake DUSEL

International Nuclear Information System (INIS)

Lesko, Kevin T.

2011-01-01

The former Homestake gold mine in Lead South Dakota is proposed for the National Science Foundation's Deep Underground Science and Engineering Laboratory (DUSEL). The gold mine provides expedient access to depths in excess of 8000 feet below the surface (>7000 mwe). Homestake's long history of promoting scientific endeavours includes the Davis Solar Neutrino Experiment, a chlorine-based experiment that was hosted at the 4850 Level for more than 30 years. As DUSEL, Homestake would be uncompromised by competition with mining interests or other shared uses. The facility's 600-km of drifts would be available for conversion for scientific and educational uses. The State of South Dakota, under Governor Rounds' leadership, has demonstrated exceptionally strong support for Homestake and the creation of DUSEL. The State has provided funding totalling $46M for the preservation of the site for DUSEL and for the conversion and operation of the Homestake Interim Laboratory. Motivated by the strong educational and outreach potential of Homestake, the State contracted a Conversion Plan by world-recognized mine-engineering contractor to define the process of rehabilitating the facility, establishing the appropriate safety program, and regaining access to the facility. The State of South Dakota has established the South Dakota Science and Technology Authority to oversee the transfer of the Homestake property to the State and the rehabilitation and preservation of the facility. The Homestake Scientific Collaboration and the State of South Dakota's Science and Technology Authority has called for Letters of Interest from scientific, educational and engineering collaborations and institutions that are interested in hosting experiments and uses in the Homestake Interim Facility in advance of the NSF's DUSEL, to define experiments starting as early as 2007. The Homestake Program Advisory Committee has reviewed these Letters and their initial report has been released. Options for

The regulation of hazardous air pollutants under the Clean Air Act Amendments of 1990: Effects on the Portland cement industry

International Nuclear Information System (INIS)

Mikols, E.H.; Gill, A.S.; Dougherty, A.

1996-01-01

Title III of the 1990 Clean Air Act Amendments (CAAA) addresses the control of hazardous air pollutants (HAPs) from major sources of air pollution in the US. In the CAAA, Congress defined 189 compounds as hazardous air pollutants in need of additional control by the Environmental Protection Agency (EPA). Congress directed EPA to identify the major source categories which emit HAPs and to prepare regulations that would reduce and control future HAP emissions. This paper outlines the activities undertaken by EPA to regulate HAP emissions from Portland cement plants and the program developed by the Portland cement manufacturing industry to cope with Title III

Effect of the use nickeliferous laterite and pumice as additives in the performance and durability of the Portland cement

Directory of Open Access Journals (Sweden)

María Carolina Rueda-Gualdrón

2016-01-01

Full Text Available En este trabajo se evalúa el comportamiento puzolánico de la laterita niquelífera de Cerromatoso (Córdoba y la pumita de Cemex (Boyacá en la preparación de morteros según normas NTC para agregados finos. Los morteros se prepararon con adiciones de 2,5%, 5% y 10% como sustitutos del cemento Portland tipo I, los cuales fueron sometidos a ensayos de resistencia mecánica antes y después de ser sometidos a ambientes extremos (altas temperaturas y ataques químicos como H2 SO4 y MgSO4 . Los resultados demuestran cómo estos materiales alternativos incrementan o disminuyen su grado de puzolanidad, así como el efecto de estos aditivos al interior de las mezclas de mortero en el tiempo, demostrando propiedades similares con relación a los morteros preparados con cemento Portland tipo I. Por lo tanto, los morteros tienen una respuesta aceptable ante las condiciones evaluadas, aunque es posible mejorar su desempeño y durabilidad, colaborando no solo con el ahorro energético en la producción del cemento Portland tipo I sino también en el uso de aditivos alternativos que permitan mitigar el impacto ambiental provocado por la industria cementera.

Interim Feed The Future Population Based Assessment of Cambodia

Data.gov (United States)

US Agency for International Development — This is the interim population based survey of Feed the Future in Cambodia for 2015. The data is split into survey modules. Modules A through C includes location...

Microbial leakage of MTA, Portland cement, Sealapex and zinc oxide-eugenol as root-end filling materials.

Science.gov (United States)

Estrela, Carlos; Estrada-Bernabé, Pedro-Felício; de Almeida-Decurcio, Daniel; Almeida-Silva, Julio; Rodrigues-Araújo-Estrela, Cyntia; Poli-Figueiredo, José-Antonio

2011-05-01

The aim of this study was to compare the microbial leakage of mineral trioxide aggregate (MTA), Portland cement (PC), Sealapex and zinc oxide-eugenol (ZOE) as root-end filling materials. An in vitro microbial leakage test (MLT) with a split chamber was used in this study. A mixture of facultative bacteria and one yeast (S. aureus+E. faecalis+P. aeruginosa+B. subtilis+C. albicans) was placed in the upper chamber and it could only reach the lower chamber containing Brain Heart Infusion broth by way of leakage through the root-end filling. Microbial leakage was observed daily for 60 days. Sixty maxillary anterior human teeth were randomly assigned to different groups--MTA and PC (gray and white), Sealapex+zinc oxide and ZOE, control groups and subgroups to evaluate the influence of EDTA for smear layer removal. These materials were further evaluated by an agar diffusion test (ADT) to verify their antimicrobial efficacy. Data were analyzed statistically by Kruskal-Wallis and Mann-Whitney test. In the MLT, Sealapex+zinc oxide and ZOE did not show evidence of microbial leakage over the 60-day experimental period. The other materials showed leakage from the 15th day. The presence of smear layer influenced microbial leakage. Microbial inhibition zones were not observed in all samples tested by ADT. Sealapex+zinc oxide and ZOE did not show microbial leakage over the experimental period, whereas it was verified within 15 to 45 days in MTA and Portland cement.

Fuel supply shutdown facility interim operational safety requirements

International Nuclear Information System (INIS)

Besser, R.L.; Brehm, J.R.; Benecke, M.W.; Remaize, J.A.

1995-01-01

These Interim Operational Safety Requirements (IOSR) for the Fuel Supply Shutdown (FSS) facility define acceptable conditions, safe boundaries, bases thereof, and management or administrative controls to ensure safe operation. The IOSRs apply to the fuel material storage buildings in various modes (operation, storage, surveillance)

Prospective Study Evaluating IncobotulinumtoxinA for Cervical Dystonia or Blepharospasm: Interim Results from the First 145 Subjects with Cervical Dystonia

Directory of Open Access Journals (Sweden)

Hubert Fernandez

2013-05-01

Full Text Available Background: We report the interim results from XCiDaBLE: A large prospective, observational "naturalistic" study evaluating Xeomin® (incobotulinumtoxinA for cervical dystonia or blepharospasm in the United States.Methods: Subjects with CD are followed for 2 treatment cycles and monitored via Interactive Voice/Web Response. Subject-reported scales include the Subject Global Impression-Severity and Improvement; Cervical Dystonia Impact Profile (CDIP-58; and Work Productivity and Quality of Life (QoL are assessed by means of an employment questionnaire and work history and the SF-12v2.Results: This ongoing study includes 145 subjects with a diagnosis of CD. The majority were female (82.3% and White (91.0% and had previously been treated with botulinum toxins (77.2%. There were 106 employed at the time of onset of the disease, but 12.6 years later only 44% were still employed at the time of enrolment into the study and 20% were either receiving or seeking disability benefits. However, only 44% were still employed at the time of recruitment for study participation. The mean total dose/treatment of CD was 225.2 units for the 1st injection. The CDIP-58 total score was significantly improved at four weeks post the first injection compared to baseline (p=<0.0001. Most subjects noted improvement in their global impression assessment. No new or unexpected adverse events occurred. Discussion: The results from these interim analyses confirm previous controlled single-dose studies of incobotulinumtoxinA in terms of efficacy and safety.

National Emission Standards for Hazardous Air Pollutants (NESHAP) for the Portland Cement Manufacturing Industry Subpart LLL Rule Guidance

Science.gov (United States)

This Spring 2016 document is intended for the use of EPA staff, State and Local regulatory agencies and their staff, and industry plant managers for the NESHAP for the Portland Cement Manufacturing Industry.

Chemical and morphological characteristics of mineral trioxide aggregate and Portland cements.

Science.gov (United States)

Khan, Shahbaz; Kaleem, Muhammad; Fareed, Muhammad Amber; Habib, Amir; Iqbal, Kefi; Aslam, Ayesha; Ud Din, Shahab

2016-01-01

The purpose of this study was to investigate the chemical composition and particle morphology of white mineral trioxide aggregate (WMTA) and two white Portland cements (CEM 1 and CEM 2). Compositional analysis was performed by energy dispersive X-ray spectroscopy, X-ray fluorescence spectrometry and X-ray diffraction whereas, morphological characteristics were analyzed by scanning electron microscope and Laser scattering particle size distribution analyzer. The elemental composition of WMTA, CEM 1 and CEM 2 were similar except for the presence of higher amounts of bismuth in WMTA. Calcium oxide and silicon oxide constitute the major portion of the three materials whereas, tricalcium silicate was detected as the major mineral phase. The particle size distribution and morphology of WMTA was finer compared to CEM 1 and CEM 2. The three tested materials had relatively similar chemical composition and irregular particle morphologies.

An allowable cladding peak temperature for spent nuclear fuels in interim dry storage

Science.gov (United States)

Cha, Hyun-Jin; Jang, Ki-Nam; Kim, Kyu-Tae

2018-01-01

Allowable cladding peak temperatures for spent fuel cladding integrity in interim dry storage were investigated, considering hydride reorientation and mechanical property degradation behaviors of unirradiated and neutron irradiated Zr-Nb cladding tubes. Cladding tube specimens were heated up to various temperatures and then cooled down under tensile hoop stresses. Cool-down specimens indicate that higher heat-up temperature and larger tensile hoop stress generated larger radial hydride precipitation and smaller tensile strength and plastic hoop strain. Unirradiated specimens generated relatively larger radial hydride precipitation and plastic strain than did neutron irradiated specimens. Assuming a minimum plastic strain requirement of 5% for cladding integrity maintenance in interim dry storage, it is proposed that a cladding peak temperature during the interim dry storage is to keep below 250 °C if cladding tubes are cooled down to room temperature.

Fabrication of an interim complete removable dental prosthesis with an in-office digital light processing three-dimensional printer: A proof-of-concept technique.

Science.gov (United States)

Lin, Wei-Shao; Harris, Bryan T; Pellerito, John; Morton, Dean

2018-04-30

This report describes a proof of concept for fabricating an interim complete removable dental prosthesis with a digital light processing 3-dimensional (3D) printer. Although an in-office 3D printer can reduce the overall production cost for an interim complete removable dental prosthesis, the process has not been validated with clinical studies. This report provided a preliminary proof of concept in developing a digital workflow for the in-office additively manufactured interim complete removable dental prosthesis. Copyright © 2018 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Temperature Characteristics of Porous Portland Cement Concrete during the Hot Summer Session

Directory of Open Access Journals (Sweden)

Liqun Hu

2017-01-01

Full Text Available Pavement heats the near-surface air and affects the thermal comfort of the human body in hot summer. Because of a large amount of connected porosity of porous Portland cement concrete (PPCC, the thermal parameters of PPCC are much different from those of traditional Portland cement concrete (PCC. The temperature change characteristics of PPCC and the effects on surrounding environment are also different. A continuous 48-hour log of temperature of a PCC and five kinds of PPCC with different porosity were recorded in the open air in the hot summer. The air temperatures at different heights above concrete specimens were tested using self-made enclosed boxes to analyze the characteristics of near-surface air temperature. The output heat flux of different concrete specimens was calculated. The results show that the PPCC has higher temperature in the daytime and lower temperature in the nighttime and larger temperature gradient than the PCC. The air temperature above PPCC is lower than that of PCC after solar radiation going to zero at night. The total output heat flux of PPCC is slightly smaller in the daytime and significantly smaller at night than that of PCC. The results of tests and calculations indicate that PPCC contributes to the mitigation of heating effect of pavement on the near-surface air.

Properties of SiMn slag as apozzolanic material in portland cement manufacture

Directory of Open Access Journals (Sweden)

Frías, M.

2005-12-01

Full Text Available The primary purpose of this study was to evaluate the behaviour of SiMn slag as a pozzolanic material in commercial Portland cement manufacture. This necessitated exploring different scientific and technical aspects to ensure a correct valuation. The results obtained revealed that silica and calcium are the main components of SiMn slag, whose pozzolanic activity occupies an intermediate position between silica fume and fly ash; it reduces heat of hydration and mortars made with cement containing SiMn slag exhibit compressive strength values similar to the figures for standard mortar. Consequently, the use of SiMn slag as an active addition to cement is feasible, inasmuch as the resulting product meets the requirements laid down in the present legislation.

El objetivo principal de este trabajo es evaluar el comportamiento de la escoria de SiMn como material puzolánico en la fabricación de cementos Portland comerciales. Para ello, resulta necesario investigar diferentes aspectos científicos y técnicos que conlleven a una correcta valorización de las mismas. Los resultados obtenidos en el presente trabajo han puesto de manifiesto que la escoria de SiMn presenta una naturaleza sílico-cálcica, actividad puzolúnica intermedia entre el humo de sílice y ceniza volante, reduce el calor de hidratación y los morteros con escoria de SiMn muestra alcanzan resistencias a compresión similares a las del mortero patrón. Por lo tanto, la utilización de la escoria de SiMn como adición activa al cemento es viable, cumpliendo con las exigencias recogidas en la norma vigente.

Failsafe automation of Phase II clinical trial interim monitoring for stopping rules.

Science.gov (United States)

Day, Roger S

2010-02-01

In Phase II clinical trials in cancer, preventing the treatment of patients on a study when current data demonstrate that the treatment is insufficiently active or too toxic has obvious benefits, both in protecting patients and in reducing sponsor costs. Considerable efforts have gone into experimental designs for Phase II clinical trials with flexible sample size, usually implemented by early stopping rules. The intended benefits will not ensue, however, if the design is not followed. Despite the best intentions, failures can occur for many reasons. The main goal is to develop an automated system for interim monitoring, as a backup system supplementing the protocol team, to ensure that patients are protected. A secondary goal is to stimulate timely recording of patient assessments. We developed key concepts and performance needs, then designed, implemented, and deployed a software solution embedded in the clinical trials database system. The system has been in place since October 2007. One clinical trial tripped the automated monitor, resulting in e-mails that initiated statistician/investigator review in timely fashion. Several essential contributing activities still require human intervention, institutional policy decisions, and institutional commitment of resources. We believe that implementing the concepts presented here will provide greater assurance that interim monitoring plans are followed and that patients are protected from inadequate response or excessive toxicity. This approach may also facilitate wider acceptance and quicker implementation of new interim monitoring algorithms.

Low-cost computer classification of land cover in the Portland area, Oregon, by signature extension techniques

Science.gov (United States)

Gaydos, Leonard

1978-01-01

Computer-aided techniques for interpreting multispectral data acquired by Landsat offer economies in the mapping of land cover. Even so, the actual establishment of the statistical classes, or "signatures," is one of the relatively more costly operations involved. Analysts have therefore been seeking cost-saving signature extension techniques that would accept training data acquired for one time or place and apply them to another. Opportunities to extend signatures occur in preprocessing steps and in the classification steps that follow. In the present example, land cover classes were derived by the simplest and most direct form of signature extension: Classes statistically derived from a Landsat scene for the Puget Sound area, Wash., were applied to the Portland area, Oreg., using data for the next Landsat scene acquired less than 25 seconds down orbit. Many features can be recognized on the reduced-scale version of the Portland land cover map shown in this report, although no statistical assessment of its accuracy is available.

17 CFR 210.8-03 - Interim financial statements.

Science.gov (United States)

2010-04-01

... 17 Commodity and Securities Exchanges 2 2010-04-01 2010-04-01 false Interim financial statements... AND CONTENT OF AND REQUIREMENTS FOR FINANCIAL STATEMENTS, SECURITIES ACT OF 1933, SECURITIES EXCHANGE... ADVISERS ACT OF 1940, AND ENERGY POLICY AND CONSERVATION ACT OF 1975 Article 8 Financial Statements of...