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Sample records for dissolution test method

  1. Comparative Application of PLS and PCR Methods to Simultaneous Quantitative Estimation and Simultaneous Dissolution Test of Zidovudine - Lamivudine Tablets.

    PubMed

    Üstündağ, Özgür; Dinç, Erdal; Özdemir, Nurten; Tilkan, M Günseli

    2015-01-01

    In the development strategies of new drug products and generic drug products, the simultaneous in-vitro dissolution behavior of oral dosage formulations is the most important indication for the quantitative estimation of efficiency and biopharmaceutical characteristics of drug substances. This is to force the related field's scientists to improve very powerful analytical methods to get more reliable, precise and accurate results in the quantitative analysis and dissolution testing of drug formulations. In this context, two new chemometric tools, partial least squares (PLS) and principal component regression (PCR) were improved for the simultaneous quantitative estimation and dissolution testing of zidovudine (ZID) and lamivudine (LAM) in a tablet dosage form. The results obtained in this study strongly encourage us to use them for the quality control, the routine analysis and the dissolution test of the marketing tablets containing ZID and LAM drugs.

  2. [The real-time FOCSDT detection method and conditions for dissolution test of metronidazole and vitamin B6 tablets].

    PubMed

    Wu, Jun; Yang, Mei; Li, Xin-Xia; Chen, Jian

    2006-09-01

    A method to monitor the dissolution rate of drug on-line fiber optic chemical sensor dissolution test(FOCSDT) was studied. Bifurcated optical fiber was used to connect the light source and detector, and the common end was dipped in the dissolution vessel. The dissolution process could be monitored through computer. The results show that the high, middle and low concentration group's recovery of metronidazole is 100.8%, 99.8% and 100.6%; and RSD is 2.5, 0.8 and 1.1 respectively, The high, middle and low Concentration group's recovery of vitamin B6 is 98.8%, 100.8% and 98.8%; and RSD is 4.1, 4.1 and 2.5 respectively. This process of analysis can test the whole process of drug and get dissolution graph. The study shows that this process analysis can reflect the real dissolution of drug and obtain the total information. PMID:17112065

  3. Content uniformity and dissolution tests of triplicate mixtures by a double divisor-ratio spectra derivative method.

    PubMed

    Markopoulou, Catherine K; Malliou, Eleftheria T; Koundourellis, John E

    2005-09-01

    The use of a UV double divisor-ratio spectra derivative calibration for the simultaneous analysis of synthetic samples and commercial tablet preparations without prior separation is proposed. The method was successfully applied to quantify three ternary mixtures, chlorpheniramine maleate and caffeine combined with paracetamol or acetylsalicylic acid and a mixture of acetylsalicylic acid combined with paracetamol and caffeine, using the information in the absorption spectra of appropriate solutions. Beer's law was obeyed in the concentration range of 0.84-4.21 microg/ml for chlorpheniramine maleate, 1.60-15.96 microg/ml for caffeine, 2.0-20.0 microg/ml for acetylsalicylic acid and 1.58-15.93 microg/ml for paracetamol. The whole procedure was applied to synthetic mixtures of pure drugs as well as to commercial preparations (Algon) by using content uniformity and dissolution tests (USP 24) and was found to be precise and reproducible. According to the dissolution profile test more than 84% of paracetamol and caffeine were dissolved within 20 min. Acetylsalicylic acid dissolved more slowly, taking about 45-60 min to dissolve completely. A chemometric method partial least squares (PLS) and a HPLC method were also employed to evaluate the same mixtures. The results of the proposed method were in excellent agreement with those obtained from PLS and HPLC methods and can be satisfactorily used for routine analysis of multicomponent dosage forms.

  4. Dissolution test acceptance sampling plans.

    PubMed

    Tsong, Y; Hammerstrom, T; Lin, K; Ong, T E

    1995-07-01

    The U.S. Pharmacopeia (USP) general monograph provides a standard for dissolution compliance with the requirements as stated in the individual USP monograph for a tablet or capsule dosage form. The acceptance rules recommended by USP have important roles in the quality control process. The USP rules and their modifications are often used as an industrial lot release sampling plan, where a lot is accepted when the tablets or capsules sampled are accepted as proof of compliance with the requirement. In this paper, the operating characteristics of the USP acceptance rules are reviewed and compared to a selected modification. The operating characteristics curves show that the USP acceptance rules are sensitive to the true mean dissolution and do not reject a lot or batch that has a large percentage of tablets that dissolve with less than the dissolution specification.

  5. Bench Scale Saltcake Dissolution Test Report

    SciTech Connect

    BECHTOLD, D.B.; PACQUET, E.A.

    2000-12-06

    A potential scenario for retrieving saltcake from single shell tanks is the ''Rainbird{reg_sign} sprinkler'' method. Water is distributed evenly across the surface of the saltcake and allowed to percolate by gravity through the waste. The salt dissolves in the water, forming a saturated solution. The saturated liquid is removed by a saltwell pump situated near the bottom of the tank. By this method, there is never a large inventory of liquid in the tank that could pose a threat of leakage. There are many variables or factors that can influence the hydrodynamics of this retrieval process. They include saltcake porosity; saltwell pumping rate; salt dissolution chemistry; factors that could promote flow channeling (e.g. tank walls, dry wells, inclusions or discontinuities in the saltcake); method of water distribution; plug formation due to crystal formations or accumulation of insoluble solids. A brief literature search indicates that very little experimental data exist on these aspects of saltcake dissolution (Wiersma 1996, 1997). The tests reported here were planned (Herting, 2000) to provide preliminary data and information for planning future, scaled-up tests of the sprinkler method.

  6. Dissolution test for silymarin tablets and capsules.

    PubMed

    Campodónico, A; Collado, E; Ricci, R; Pappa, H; Segall, A; Pizzorno, M T

    2001-01-01

    Silybine (SBN), isosilybine (ISBN), silycristine (SCN), silydianine (SDN), and taxifoline (TXF) are the main active flavonoids commonly found in the dried fruits of Silybum marianum, Gaertner (Compositae). Concentrations of these compounds, except TXF, are usually expressed together as silymarin content. This paper describes a simple dissolution test developed to estimate silymarin (Sl) in pharmaceutical formulations. Five commercial products were tested using this new method (including tablets, sugar tablets, and capsules): two from Argentina, one from Brazil, one from Spain, and one from Italy. Results demonstrated that, provided the dosage form disintegrates, amounts dissolved range from 50 to 90% of the labeled value. Products were analyzed by high performance liquid chromatography (HPLC) and UV spectrophotometry.

  7. [Improvement of dissolution test using micro-controlled roller pump].

    PubMed

    Nagai, Noriaki; Konishi, Nahoko; Nitta, Tadahisa; Taga, Atsushi; Ito, Yoshimasa

    2012-01-01

    The dissolution test is a core performance test in pharmaceutical development and quality control of solid drug products. The conventional HPLC dissolution method (batch-sampling method) involves many steps including the filtration, collection and replenishment of sample solutions. We previously reported a dissolution test that involved microdialysis methods (microdialysis-HPLC method) and allowed many steps to be omitted. However, the recovery rate of theophylline by the microdialysis-HPLC method was lower, and the decrease in the flow rate through the dialysis probe caused variation between each tablet. In this study, we have attempted to improve the dissolution test by using a precise micro-controlled roller pump and microfiltering probe (microfiltering-HPLC method). Sustained release preparations of Theodur (100 mg) were used, and the test solutions used were water, buffer at pH 1.2 and pH 6.8, and pH 6.8-buffer containing 0.1-1% polysorbate 80 or sodium lauryl sulfate. In all test solutions, the microfiltering-HPLC method was able to accomplish continuous sampling of sample solutions, and the recovery rate of theophylline was over 90%. The dissolution behavior by the microfiltering-HPLC method tends to reflect the pharmaceutical design in comparison with the batch-sampling method, and the standard deviations by the microfiltering-HPLC are lower than with the batch-sampling method. In addition, the microfiltering-HPLC method allows many steps to be omitted, such as the filtration, collection and replenishment of sample solutions. These findings provide significant information that can be used in the pharmaceutical development and quality assessment of solid drug products.

  8. Automated Dissolution for Enteric-Coated Aspirin Tablets: A Case Study for Method Transfer to a RoboDis II.

    PubMed

    Ibrahim, Sarah A; Martini, Luigi

    2014-08-01

    Dissolution method transfer is a complicated yet common process in the pharmaceutical industry. With increased pharmaceutical product manufacturing and dissolution acceptance requirements, dissolution testing has become one of the most labor-intensive quality control testing methods. There is an increased trend for automation in dissolution testing, particularly for large pharmaceutical companies to reduce variability and increase personnel efficiency. There is no official guideline for dissolution testing method transfer from a manual, semi-automated, to automated dissolution tester. In this study, a manual multipoint dissolution testing procedure for an enteric-coated aspirin tablet was transferred effectively and reproducibly to a fully automated dissolution testing device, RoboDis II. Enteric-coated aspirin samples were used as a model formulation to assess the feasibility and accuracy of media pH change during continuous automated dissolution testing. Several RoboDis II parameters were evaluated to ensure the integrity and equivalency of dissolution method transfer from a manual dissolution tester. This current study provides a systematic outline for the transfer of the manual dissolution testing protocol to an automated dissolution tester. This study further supports that automated dissolution testers compliant with regulatory requirements and similar to manual dissolution testers facilitate method transfer.

  9. 21 CFR 343.90 - Dissolution and drug release testing.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...-COUNTER HUMAN USE Testing Procedures § 343.90 Dissolution and drug release testing. (a) (b) Aspirin capsules. Aspirin capsules must meet the dissolution standard for aspirin capsules as contained in the United States Pharmacopeia (USP) 23 at page 132. (c) Aspirin delayed-release capsules and aspirin...

  10. 21 CFR 343.90 - Dissolution and drug release testing.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...-COUNTER HUMAN USE Testing Procedures § 343.90 Dissolution and drug release testing. (a) (b) Aspirin capsules. Aspirin capsules must meet the dissolution standard for aspirin capsules as contained in the United States Pharmacopeia (USP) 23 at page 132. (c) Aspirin delayed-release capsules and aspirin...

  11. 21 CFR 343.90 - Dissolution and drug release testing.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...-COUNTER HUMAN USE Testing Procedures § 343.90 Dissolution and drug release testing. (a) (b) Aspirin capsules. Aspirin capsules must meet the dissolution standard for aspirin capsules as contained in the United States Pharmacopeia (USP) 23 at page 132. (c) Aspirin delayed-release capsules and aspirin...

  12. 21 CFR 343.90 - Dissolution and drug release testing.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...-COUNTER HUMAN USE Testing Procedures § 343.90 Dissolution and drug release testing. (a) (b) Aspirin capsules. Aspirin capsules must meet the dissolution standard for aspirin capsules as contained in the United States Pharmacopeia (USP) 23 at page 132. (c) Aspirin delayed-release capsules and aspirin...

  13. 21 CFR 343.90 - Dissolution and drug release testing.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...-COUNTER HUMAN USE Testing Procedures § 343.90 Dissolution and drug release testing. (a) (b) Aspirin capsules. Aspirin capsules must meet the dissolution standard for aspirin capsules as contained in the United States Pharmacopeia (USP) 23 at page 132. (c) Aspirin delayed-release capsules and aspirin...

  14. Development and Validation of Discriminating and Biorelevant Dissolution Test for Lornoxicam Tablets

    PubMed Central

    Anumolu, P. D.; Sunitha, G.; Bindu, S. Hima; Satheshbabu, P. R.; Subrahmanyam, C. V. S.

    2015-01-01

    The establishment of biorelevant and discriminating dissolution procedure for drug products with limited water solubility is a useful technique for qualitative forecasting of the in vivo behavior of formulations. It also characterizes the drug product performance in pharmaceutical development. Lornoxicam, a BCS class-II drug is a nonsteroidal antiinflammatory drug of the oxicam class, has no official dissolution media available in the literature. The objective of present work was to develop and validate a discriminating and biorelevant dissolution test for lornoxicam tablet dosage forms. To quantify the lornoxicam in dissolution samples, UV spectrophotometric method was developed using 0.01M sodium hydroxide solution as solvent at λma×376 nm. After evaluation of saturation solubility, dissolution, sink conditions and stability of lornoxicam bulk drug in different pH solutions and biorelevant media, the dissolution method was optimized using USP paddle type apparatus at 50 rpm rotation speed and 500 ml simulated intestinal fluid as discriminating and biorelevant dissolution medium. The similarity factor (f2) were investigated for formulations with changes in composition and manufacturing variations, values revealed that dissolution method having discriminating power and method was validated as per standard guidelines. The proposed dissolution method can be effectively applied for routine quality control in vitro dissolution studies of lornoxicam in tablets and helpful to pharmacopoeias. PMID:26180277

  15. Pilot-scale tests of HEME and HEPA dissolution process

    SciTech Connect

    Qureshi, Z.H.; Strege, D.K.

    1994-06-01

    A series of pilot-scale demonstration tests for the dissolution of High Efficiency Mist Eliminators (HEME`s) and High Efficiency Particulate Airfilters (HEPA) were performed on a 1/5th linear scale. These fiberglass filters are to be used in the Defense Waste Processing Facility (DWPF) to decontaminate the effluents from the off-gases generated during the feed preparation process and vitrification. When removed, these filters will be dissolved in the Decontamination Waste Treatment Tank (DWTT) using 5 wt% NaOH solution. The contaminated fiberglass is converted to an aqueous stream which will be transferred to the waste tanks. The filter metal structure will be rinsed with process water before its disposal as low-level solid waste. The pilot-scale study reported here successfully demonstrated a simple one step process using 5 wt% NaOH solution. The proposed process requires the installation of a new water spray ring with 30 nozzles. In addition to the reduced waste generated, the total process time is reduced to 48 hours only (66% saving in time). The pilot-scale tests clearly demonstrated that the dissolution process of HEMEs has two stages - chemical digestion of the filter and mechanical erosion of the digested filter. The digestion is achieved by a boiling 5 wt% caustic solutions, whereas the mechanical break down of the digested filter is successfully achieved by spraying process water on the digested filter. An alternate method of breaking down the digested filter by increased air sparging of the solution was found to be marginally successful are best. The pilot-scale tests also demonstrated that the products of dissolution are easily pumpable by a centrifugal pump.

  16. Oral dosage form performance tests: new dissolution approaches.

    PubMed

    Hauck, Walter W; Foster, Thomas; Sheinin, Eric; Cecil, Todd; Brown, William; Marques, Margareth; Williams, Roger L

    2005-02-01

    The performance test is one of a series of tests that compose the specification in a United States Pharmacopeia (USP) dosage form monograph. For an orally administered, nonsolution dosage form, it is usually satisfied by either a dissolution or disintegration procedure. Dissolution acceptance criteria are usually set in private negotiations between an applicant and a regulatory agency. With information about this private agreement and other information provided in a sponsor's Request for Revision to USP, the USP's Council of Experts elaborates a public dosage form monograph. Based on the relationship between the regulatory decisions and the Request for Revision, the USP dissolution procedure links to a regulatory judgment about bioavailability and bioequivalence and, ultimately, to a judgment about safety and efficacy. The current dissolution procedure and acceptance criteria are perceived as having worked well over the years and are generally accepted. This article discusses new approaches that merit consideration. These approaches focus on a) explicit use of hypothesis testing, b) use of parametric tolerance intervals, c) improved ways to set dissolution acceptance criteria, and d) a more flexible protocol to assess conformity. Application of the proposed approaches may better assess, manage, and communicate both manufacturer and consumer risk for dissolution testing.

  17. Modeling solid-state transformations occurring in dissolution testing.

    PubMed

    Laaksonen, Timo; Aaltonen, Jaakko

    2013-04-15

    Changes in the solid-state form can occur during dissolution testing of drugs. This can often complicate interpretation of results. Additionally, there can be several mechanisms through which such a change proceeds, e.g. solvent-mediated transformation or crystal growth within the drug material itself. Here, a mathematical model was constructed to study the dissolution testing of a material, which undergoes such changes. The model consisted of two processes: the recrystallization of the drug from a supersaturated liquid state caused by the dissolution of the more soluble solid form and the crystal growth of the stable solid form at the surface of the drug formulation. Comparison to experimental data on theophylline dissolution showed that the results obtained with the model matched real solid-state changes and that it was able to distinguish between cases where the transformation was controlled either by solvent-mediated crystallization or solid-state crystal growth. PMID:23506958

  18. Dissolution test for ivermectin in oral veterinary paste.

    PubMed

    Sznitowska, M; Pietkiewicz, J; Stokrocka, M; Janicki, S

    2004-10-01

    A dissolution test for oral veterinary pastes with ivermectin using the Ph. Eur. paddle apparatus was developed. Sink conditions were achieved with sodium lauryl sulphate in a concentration of 0.5% as dissolution medium. By means of HPLC fast degradation of ivermectin was observed in HCl 0.1 M solution. Rotation speed of the paddle at 75 rpm was appropriate as demonstrated in a study comparing two different products. PMID:15544065

  19. A novel off-center paddle impeller (OPI) dissolution testing system for reproducible dissolution testing of solid dosage forms.

    PubMed

    Wang, Yimin; Armenante, Piero M

    2012-02-01

    Dissolution testing is routinely conducted in the pharmaceutical industry to provide in vitro drug release information for quality control purposes. The most common dissolution testing system for solid dosage forms is the United States Pharmacopeia (USP) Dissolution Testing Apparatus 2. This apparatus is very sensitive to the initial location of the tablet, which cannot be controlled because the tablet is dropped into the vessel at the beginning of the test and it may rest at random locations at the vessel's bottom. In this work, a modified Apparatus 2 in which the impeller was placed 8 mm off center in the vessel was designed and tested. This new design was termed "OPI" for "off-center paddle impeller." Dissolution tests were conducted with the OPI apparatus for nine different tablet locations using both disintegrating tablets (prednisone) and nondisintegrating tablets (salicylic acid). The dissolution profiles in the OPI apparatus were largely independent of the tablet location at the vessel's bottom, whereas those obtained in the Standard System generated statistically different profiles depending on the tablet location. The newly proposed OPI system can effectively eliminate artifacts generated by random settling of the tablet at the vessel's bottom, thus making the test more robust.

  20. Glass Dissolution: Testing and Modeling for Long-Term Behavior.

    SciTech Connect

    Strachan, Denis M. )

    2001-09-01

    The basic concepts of thermodynamics and kinetics are discussed in relationship to glass dissolution testing. While it seems like these subjects are too basic to be discussed in a journal article, it is often the case that we forget these concepts when planning and designing dissolution tests and interpreting the results that come from these tests. The possible connection between the composition of the dissolving glass and its long-term behavior is discussed. Results from a preliminary study suggest that the aluminum content of a glass is important to its long-term behavior. The formation of a zeolite can cause the glass dissolution rate to increase under certain conditions that can be modeled. Results indicate that complex glasses can be modeled with a glass containing as little as six components.

  1. Three-stage sequential statistical dissolution testing rules.

    PubMed

    Tsong, Yi; Shen, Meiyu; Shah, Vinod P

    2004-08-01

    The U.S. Pharmacopoeia (USP) general monograph provides a standard for dissolution compliance with the requirements as stated in the individual USP monograph for a tablet or capsule dosage form. The USP monograph sets performance limit on dissolution in terms of a specific percentage Q that the drug product is required to be dissolved at a specified time. Japan Pharmacopoeia provides acceptance rules different from USP. However the objective of the acceptance rules was not defined in terms of the inference of the whole lot by either USP, European Pharmacopoeia (EP) or Japan Pharmacopoeia (JP). The operating characteristics' curves of these rules are all shown to be sensitive to the true mean dissolution and do not reject a lot which has a large percentage of tablets that dissolve with less than the specified limit Q. This is especially true when the mean dissolution is close to the specification value. We proposed that the goal of the dissolution test sampling plan is to accept a lot at least 90% of the tablets dissolved more than a pre-specified amount Q at the specific time. The group sequential procedure derived accordingly is shown to outperform both USP and JP in controlling the type I error rate under normality assumption.

  2. Development and Validation of a Dissolution Test for Meloxicam and Pridinol Mesylate from Combined Tablet Formulation

    PubMed Central

    Vignaduzzo, S. E.; Castellano, P. M.; Kaufman, T. S.

    2010-01-01

    The association of meloxicam and pridinol is indicated for treating muscular contractures and low back pain. A dissolution test for the meloxicam-pridinol combined tablet formulation was developed and validated, using a suitable HPLC method for simultaneously quantitating both dissolved drugs. The optimized conditions include the use of USP apparatus 2 at a paddle rotation rate of 75 rpm and 900 ml of 50 mM phosphate buffer (pH= 7.5) as dissolution medium, at 37.0±0.5°. The test, which demonstrated to be robust against small changes in bath temperature, paddle rotation speed and pH of the dissolution medium, was applied to two different brands of tablets; the corresponding dissolution profiles were constructed and both brands showed to dissolve at least 75% of the drugs at the 45 min time point. PMID:20838523

  3. Test Objectives for the Saltcake Dissolution Retrieval Demonstration

    SciTech Connect

    DEFIGH PRICE, C.

    2000-09-22

    This document describes the objectives the Saltcake Dissolution Retrieval Demonstration. The near term strategy for single-shell tank waste retrieval activities has shifted from focusing on maximizing the number of tanks entered for retrieval (regardless of waste volume or content) to a focus on scheduling the retrieval of wastes from those single-shell tanks with a high volume of contaminants of concern. These contaminants are defined as mobile, long-lived radionuclides that have a potential of reaching the groundwater and the Columbia River. This strategy also focuses on the performance of key retrieval technology demonstrations, including the Saltcake Dissolution Retrieval Demonstration, in a variety of waste forms and tank farm locations to establish a technical basis for future work. The work scope will also focus on the performance of risk assessment, retrieval performance evaluations (RPE) and incorporating vadose zone characterization data on a tank-by-tank basis, and on updating tank farm closure/post closure work plans. The deployment of a retrieval technology other than Past-Practice Sluicing (PPS) allows determination of limits of technical capabilities, as well as, providing a solid planning basis for future SST retrievals. This saltcake dissolution technology deployment test will determine if saltcake dissolution is a viable retrieval option for SST retrieval. CH2M Hill Hanford Group (CHG) recognizes the SST retrieval mission is key to the success of the River Protection Project (RPP) and the overall completion of the Hanford Site cleanup. The objectives outlined in this document will be incorporated into and used to develop the test and evaluation plan for saltcake dissolution retrievals. The test and evaluation plan will be developed in fiscal year 2001.

  4. Validation of analytical methods involved in dissolution assays: acceptance limits and decision methodologies.

    PubMed

    Rozet, E; Ziemons, E; Marini, R D; Boulanger, B; Hubert, Ph

    2012-11-01

    Dissolution tests are key elements to ensure continuing product quality and performance. The ultimate goal of these tests is to assure consistent product quality within a defined set of specification criteria. Validation of an analytical method aimed at assessing the dissolution profile of products or at verifying pharmacopoeias compliance should demonstrate that this analytical method is able to correctly declare two dissolution profiles as similar or drug products as compliant with respect to their specifications. It is essential to ensure that these analytical methods are fit for their purpose. Method validation is aimed at providing this guarantee. However, even in the ICHQ2 guideline there is no information explaining how to decide whether the method under validation is valid for its final purpose or not. Are the entire validation criterion needed to ensure that a Quality Control (QC) analytical method for dissolution test is valid? What acceptance limits should be set on these criteria? How to decide about method's validity? These are the questions that this work aims at answering. Focus is made to comply with the current implementation of the Quality by Design (QbD) principles in the pharmaceutical industry in order to allow to correctly defining the Analytical Target Profile (ATP) of analytical methods involved in dissolution tests. Analytical method validation is then the natural demonstration that the developed methods are fit for their intended purpose and is not any more the inconsiderate checklist validation approach still generally performed to complete the filing required to obtain product marketing authorization. PMID:23084050

  5. Interlaboratory study of the reproducibility of the single-pass flow-through test method : measuring the dissolution rate of LRM glass at 70 {sup {degree}}C and pH 10.

    SciTech Connect

    Ebert, W. L.; Chemical Engineering

    2006-02-28

    An international interlaboratory study (ILS) was conducted to evaluate the precision with which single-pass flow-through (SPFT) tests can be conducted by following a method to be standardized by the American Society for Testing and Materials - International. Tests for the ILS were conducted with the low-activity reference material (LRM) glass developed previously for use as a glass test standard. Tests were conducted at 70 {+-} 2 C using a LiCl/LiOH solution as the leachant to impose an initial pH of about 10 (at 70 C). Participants were provided with LRM glass that had been crushed and sieved to isolate the -100 +200 mesh size fraction, and then washed to remove fines. Participants were asked to conduct a series of tests using different solution flow rate-to-sample mass ratios to generate a range of steady-state Si concentrations. The glass dissolution rate under each test condition was calculated using the steady-state Si concentration and solution flow rate that were measured in the test. The glass surface area was estimated from the mass of glass used in the test and the Si content of LRM glass was known. A linear relationship between the rate and the steady-state Si concentration (at Si concentrations less than 10 mg/L) was used to estimate the forward dissolution rate, which is the rate in the absence of dissolved Si. Participants were asked to sample the effluent solution at least five times after reaction times of between 3 and 14 days to measure the Si concentration and flow rate, and to verify that steady-state was achieved. Results were provided by seven participants and the data sets provided by five participants were sufficient to determine the forward rates independently.

  6. Development of Alkaline Oxidative Dissolution Methods for Chromium (III) Compounds Present in Hanford Site Tank Sludges

    SciTech Connect

    NN Krot; VP Shilov; AM Fedoseev; NA Budantseva; MV Nikonov; AB Yusov; AYu Garnov; IA Charushnikova; VP Perminov; LN Astafurova; TS Lapitskaya; VI Makarenkov

    1999-07-02

    The high-level radioactive waste sludge in the underground storage tanks at the Hanford Site contains various chromium(III)solid phases. Dissolution and removal of chromium from tank waste sludges is desirable prior to high-level waste vitrification because increased volume is required to incorporate the residual chromium. Unfortunately, dissolution of chromium from the sludge to form Cr(OH){sub 4}{sup {minus}} through treatment with heated NaOH solution (also used to dissolve aluminum phases and metathesize phosphates to sodium salts) generally has been unsuccessful in tests with both simulated and genuine Hanford waste sludges. Oxidative dissolution of the Cr(III) compounds to form soluble chromate has been proposed as an alternative chromium solid phase dissolution method and results of limited prior testing have been reported.

  7. Solar Radiation Management and Olivine Dissolution Methods in Climate Engineering

    NASA Astrophysics Data System (ADS)

    Kone, S.

    2014-12-01

    An overview of solar radiation management and olivine dissolution methods allows to discuss, comparatively, the benefits and consequences of these two geoengineering techniques. The combination of those two techniques allows to concomitantly act on the two main agents intervening in global warming: solar radiation and carbon dioxide. The earth surface temperature increases due mainly to carbon dioxide (a greenhouse gas) that keeps the solar radiation and causes the global warming. Two complementary methods to mitigate climate change are overviewed: SRM method, which uses injected aerosols, aims to reduce the amount of the inbound solar radiation in atmosphere; and olivine dissolution in water, a key chemical reaction envisaged in climate engineering , aiming to reduce the amount of the carbon dioxide in extracting it from atmosphere. The SRM method works on scenarios of solar radiation decrease and the olivine dissolution method works as a carbon dioxide sequestration method. Olivine dissolution in water impacts negatively on the pH of rivers but positively in counteracting ocean acidification and in transporting the silica in ocean, which has benefits for diatom shell formation.

  8. DISSOLUTION METHOD OF REMOVING BONDING AGENTS

    DOEpatents

    Hyman, H.H.

    1960-04-19

    A method is given for removing residual aluminumsilicon bonding agents from uranium slugs after the removal of aluminum coatings. To accomplish this the slug is immersed in an aqueous solution about 0.75 N in hydrofluoric acid and about 7 N in nitric acid.

  9. Dissolution study of nanocrystal powders of a poorly soluble drug by UV imaging and channel flow methods.

    PubMed

    Sarnes, Annika; Østergaard, Jesper; Jensen, Sabrine Smedegaard; Aaltonen, Jaakko; Rantanen, Jukka; Hirvonen, Jouni; Peltonen, Leena

    2013-11-20

    Application of drug nanocrystals provides advantageous options for the pharmaceutical formulation development of poorly soluble drugs. The objective of this study was to investigate the dissolution behavior improving effects of differently sized nanocrystals of a poorly soluble model drug, indomethacin. Nanocrystal suspensions were prepared using a top-down wet milling technique with three stabilizers: poloxamer F68, poloxamer F127 and polysorbate 80. The dissolution of the differently sized indomethacin nanocrystals were investigated using a channel flow dissolution method and by UV imaging. Unmilled bulk indomethacin and physical mixtures were used as references. According to both the dissolution methods, the dissolution properties of indomethacin were improved by the particle size reduction. UV imaging was used for the first time as a dissolution testing method for fast dissolving nanoscale material. The technique provided new information about the concentration of the dissolved drug next to the sample surface; with the smallest nanocrystals (580 nm) the indomethacin concentration next to the particle surface exceeded five-fold the thermodynamic saturated indomethacin solution concentration. Thus the solubility improvement itself, not only the increased surface area for dissolution, may have an important role in the higher dissolution rates of nanocrystal formulations. Poloxamer F68 was the most optimal stabilizer in the preparation of the indomethacin nanocrystal suspensions and in the solubility and dissolution enhancement as well.

  10. Development of a Suitable Dissolution Method for the Combined Tablet Formulation of Atorvastatin and Ezetimibe by RP-LC Method.

    PubMed

    Ozkan Cansel, Kose; Ozgur, Esim; Sevinc, Kurbanoglu; Ayhan, Savaser; Ozkan, Sibel A; Yalcin, Ozkan

    2016-01-01

    Pharmaceutical preparations of ezetimibe and atorvastatin are generally used to regulate the lipid level in blood. It decreases the secondary events for patients with high cholesterol and clinical cardiovascular disease such as non-fatal or fatal heart attack. There is no any pharmacopoeia method available for the dissolution testing recommended by the FDA. Development of dissolution tests method is very critical parameter especially for the pharmaceutical preparations that contain Class II drugs (slightly soluble, good permeable). In the proposed method, the effects of pH and surfactant on the dissolution of poorly water soluble combined drug therapy with a different pKa values in an in vitro environment is investigated. The content of our study was designed to answer these open-ended questions. The optimized test conditions achieved under sink conditions with USP apparatus 2 at a paddle rotation speed of 75 rpm and 900 ml in 0.01 M Acetate buffer (pH= 6.8) containing 0.45% SDS as a dissolution medium. Quantification of dissolution samples were analyzed with a new fully validated RP-LC method with UV detection at 242 nm. PMID:26638976

  11. Screening method to identify preclinical liquid and semi-solid formulations for low solubility compounds: miniaturization and automation of solvent casting and dissolution testing.

    PubMed

    Mansky, Paul; Dai, Wei-Guo; Li, Shu; Pollock-Dove, Crystal; Daehne, Klaus; Dong, Liang; Eichenbaum, Gary

    2007-06-01

    We have developed an efficient screening method to identify liquid and semisolid formulations for low-solubility compounds. The method is most suitable for identifying dosing vehicles for compounds in lead optimization, where compound supply is limited and long-term stability is not a requirement. Dilute compound and excipient stock solutions are prepared in organic solvent and then dispensed and mixed in 96-well plates. The solvent is removed in a vacuum centrifuge evaporator, leaving neat formulation (e.g., 10-40 microg compound, 0.4 mg excipient) at the bottom of each well. After an aging step, an aqueous dilution medium is added and the plates are incubated (agitation by orbital shaking). The diluted formulations are then filtered and analyzed by ultraviolet (UV) absorbance or high-performance liquid chromatography (HPLC). To illustrate the method, two compounds (aqueous solubility method to screening compound/surfactant/oil formulations is also presented.

  12. Development and evaluation of methods for starch dissolution using asymmetrical flow field-flow fractionation. Part II: Dissolution of amylose.

    PubMed

    Perez-Rea, Daysi; Bergenståhl, Björn; Nilsson, Lars

    2016-02-01

    In this paper, we investigate whether dissolution in water under autoclaving conditions (140 °C, 20 min) or in dimethyl sulfoxide, DMSO (100 °C, 1 h), is preferable for characterization of amylose. Two types of amylose, potato and maize, were dissolved either in water using an autoclave or in DMSO. On the aqueous solutions obtained, the extent of molecular dissolution of the sample (referred to as the dissolution yield) was determined by enzymatic analysis as well as the molecular properties, such as molar mass and root-mean-square radius, obtained with asymmetrical flow field-flow fractionation coupled to multi-angle light scattering and differential refractive index detection (AF4-MALS-dRI). The results showed that both dissolution methods are efficient at dissolving amylose. However, AF4-MALS-dRI analysis revealed substantial differences. Amylose aqueous solutions obtained by dissolution in DMSO were relatively stable over time, but the dissolution method in autoclave caused some degradation of the molecules, and their solutions display a high tendency to retrograde. PMID:26232931

  13. K Basin Sludge Conditioning Testing: Nitric Acid Dissolution Testing of K East Canister Sludge

    SciTech Connect

    Carlson, C.D.; Delegard, C.H.; Burgeson, I.E.: Schmidt, A.J.; Bredt, P.R.; Silvers, K.L.

    1999-04-01

    This report describes tests performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) as part of the overall activities for the development of the K Basin Sludge Treatment System. These tests were conducted to examine the dissolution behavior of a K East Basin canister sludge composite in nitric acid at the following concentrations: 2 M, 4 M, 6 M, 7.8 M and 10 M and temperatures of 25 C and boiling. Assuming that the sludge was 100% uranium metal, a 4X stoichiometric excess of nitric acid was used for all testing, except that conducted at 4 M. In the 4 M nitric acid dissolution test, 50% excess nitric acid was used resulting in a dissolver solution with a significantly higher solids loading. The boiling tests were conducted for 11 hr, the 25 C dissolution tests were conducted from 24 hr to 2 weeks. For the 25 C dissolution testing, the weight percent residual solids was determined, however, chemical and radiochemical analyses were not performed.

  14. Development and validation of dissolution testings in acidic media for rabeprazole sodium delayed-release capsules.

    PubMed

    Tan, Yinhe; Si, Xiaoqing; Zhong, Lulu; Feng, Xin; Yang, Xinmin; Huang, Min; Wu, Chuanbin

    2016-10-01

    Rabeprazole sodium (RAB) dissolved in acidic media is accompanied by its degradation in the course of dissolution testing. To develop and establish the accumulative release profiles of ACIPHEX(®) Sprinkle (RAB) delayed-release capsules (ACIPHEX(®) Sprinkle) in acidic media using USP apparatus 2 (paddle apparatus) as a dissolution tester, the issues of determination of accumulative release amount of RAB in these acidic media and interference of hydroxypropylmethyl cellulose phthalate were solved by adding appropriate hydrochloric acid (HCl) into dissolution samples coupled with centrifugation so as to remove the interference and form a solution of degradation products of RAB, which is of a considerably stable ultraviolet (UV) absorbance at the wavelength of 298 nm within 2.0 h. Therefore, the accumulative release amount of RAB in dissolution samples at each sample time points could be determined by UV-spectrophotometry, and the accumulative release profiles of ACIPHEX(®) Sprinkle in the media of pH 1.0, pH 6.0, and pH 6.8 could be established. The method was validated per as the ICH Q2 (R1) guidelines and demonstrated to be adequate for quality control of ACIPHEX(®) Sprinkle and the accumulative release profiles can be used as a tool to guide the formulation development and quality control of a generic drug for ACIPHEX(®) Sprinkle. PMID:27066697

  15. Calcination/dissolution testing for Hanford Site tank wastes

    SciTech Connect

    Colby, S.A.; Delegard, C.H.; McLaughlin, D.F.; Danielson, M.J.

    1994-07-01

    Thermal treatment by calcination offers several benefits for the treatment of Hanford Site tank wastes, including the destruction of organics and ferrocyanides and an hydroxide fusion that permits the bulk of the mostly soluble nonradioactive constituents to be easily separated from the insoluble transuranic residue. Critical design parameters were tested, including: (1) calciner equipment design, (2) hydroxide fusion chemistry, and (3) equipment corrosion. A 2 gal/minute pilot plant processed a simulated Tank 101-SY waste and produced a free flowing 700 C molten calcine with an average calciner retention time of 20 minutes and >95% organic, nitrate, and nitrite destruction. Laboratory experiments using actual radioactive tank waste and the simulated waste pilot experiments indicate that 98 wt% of the calcine produced is soluble in water, leaving an insoluble transuranic fraction. All of the Hanford Site tank wastes can benefit from calcination/dissolution processing, contingent upon blending various tank waste types to ensure a target of 70 wt% sodium hydroxide/nitrate/nitrite fluxing agent. Finally, corrosion testing indicates that a jacketed nickel liner cooled to below 400 C would corrode <2 mil/year (0.05 mm/year) from molten calcine attack.

  16. Dating of black gel pen ink using the dissolution-diffusion method.

    PubMed

    Li, Biao

    2014-01-01

    In many criminal and civil cases in China, the most commonly questioned documents are those written with gel pen ink. An important task for forensic document examiners is to identify whether two or more ink entries in one or more documents were written with the same ink type. The identification of the age of gel ink entries made poses an important and difficult problem for forensic document examiners. In this paper, a dissolution-diffusion method was successfully employed to estimate the relative age of gel ink entries by comparing dissolution-diffusion rates. Using extensive tests, the mixed solution of dimethyl formamide (DMF) and anhydrous ethanol proved to be a suitable solvent and was used to dissolve the dye of gel ink strokes made at different times. As preliminary findings of this study, calibration curves were created to indicate the relationship between the average dissolution-diffusion rate of soluble gel ink components and the age of gel ink entries stored under natural aging conditions. It was also determined that brands of gel inks, types of paper and thickness of gel ink strokes had varying impacts on estimating the dates of gel ink strokes. Experimental results showed that dissolution-diffusion method was applicable for determining the relative age of gel ink entries under certain conditions. PMID:24378312

  17. Enabling real time release testing by NIR prediction of dissolution of tablets made by continuous direct compression (CDC).

    PubMed

    Pawar, Pallavi; Wang, Yifan; Keyvan, Golshid; Callegari, Gerardo; Cuitino, Alberto; Muzzio, Fernando

    2016-10-15

    A method for predicting dissolution profiles of directly compressed tablets for a fixed sustained release formulation manufactured in a continuous direct compaction (CDC) system is presented. The methodology enables real-time release testing (RTRt). Tablets were made at a target drug concentration of 9% Acetaminophen, containing 90% lactose and 1% Magnesium Stearate, and at a target compression force of 24kN. A model for predicting dissolution profiles was developed using a 3(4-1) fractional factorial experimental design built around this targeted condition. Four variables were included: API concentration (low, medium, high), blender speed (150rpm, 200rpm, 250rpm), feed frame speed (20rpm, 25rpm, 30rpm), compaction force (8KN, 16KN, 24KN). The tablets thus obtained were scanned at-line in transmission mode using Near IR spectroscopy. The dissolution profiles were described using two approaches, a model-independent "shape and level" method, and a model-dependent approach based on Weibull's model. Multivariate regression was built between the NIR scores as the predictor variables and the dissolution profile parameters as the response. The model successfully predicted the dissolution profiles of the individual tablets (similarity factor, f2 ∼72) manufactured at the targeted set point. This is a first ever published manuscript addressing RTRt for dissolution prediction in continuous manufacturing, a novel and state of art technique for tablet manufacturing. PMID:27543350

  18. Solution calorimetry as an alternative approach for dissolution testing of nanosuspensions.

    PubMed

    Kayaert, P; Li, B; Jimidar, I; Rombaut, P; Ahssini, F; Van den Mooter, G

    2010-11-01

    The formulation of poorly soluble drugs as nanocrystals/nanosuspensions has rapidly evolved during the past decade into a mature drug-delivery strategy. The major characteristic of these systems is the high drug dissolution rate, enabling bioavailability enhancement after oral administration. It is therefore of great importance to have access to analytical methodology that is able to accurately monitor the extreme fast dissolution process of such formulations. The aim of the present study was to evaluate solution calorimetry as a novel approach to measure the dissolution rate of nanosuspensions by recording the temperature change in the dissolution vessel during the dissolution process of the nanocrystals. The applicability was tested on different nanosuspensions made up of three model drugs: naproxen, cinnarizine and an investigational API, i.e. compound A. The dissolution process of all nanosuspensions investigated was completed within less than 1 min. During this period, sufficient data points were collected to transform temperature offset data to cumulative heat of solution pointing to the potential of this technique. However, of significant concern is the fact that this technique measures the total heat produced or consumed by all processes that occur during the dissolution, e.g. the heat of mixing when the nanosuspension comes in contact with the dissolution medium. Erroneous conclusions will result if phenomena other than dissolution are not accounted for. PMID:20887787

  19. Commentary on AAPS Workshop: dissolution testing for the twenty-first century: linking critical quality attributes and critical process parameters to clinically relevant dissolution.

    PubMed

    Tong, Cheng; D'Souza, Susan S; Parker, Jan E; Mirza, Tahseen

    2007-09-01

    This is a summary report of the workshop entitled "Dissolution Testing for the Twenty-first Century: Linking Critical Quality Attributes and Critical Process Parameters to Clinically Relevant Dissolution," organized by the In Vitro Release and Dissolution Testing Focus Group of the American Association of Pharmaceutical Scientists. Participants from the pharmaceutical industry, regulatory authorities, and academia in the US, Europe, and Japan attended this workshop to review, discuss, and explore the role of traditional dissolution testing in the new arena of Quality by Design (QbD) and Process Analytical Technology (PAT). Other areas of discussion were the use of the dissolution test to evaluate drug release from novel dosage forms, challenges in dissolution testing and specification setting, and dissolution apparatus calibration using performance verification tablets versus mechanical calibration. The workshop identified areas where further research and collaboration are needed to advance knowledge and understanding of the science of dissolution. Views expressed in this report are those of the authors and do not necessarily reflect those of the FDA and USP.

  20. High-Speed Intrinsic Dissolution Rate in One Minute Using the Single-Particle Intrinsic Dissolution Rate Method.

    PubMed

    Svanbäck, Sami; Ehlers, Henrik; Antikainen, Osmo; Yliruusi, Jouko

    2015-11-01

    Intrinsic dissolution rate (IDR) has traditionally been determined from a constant surface area of a substance. Here we present an optofluidic single-particle intrinsic dissolution rate (SIDR) method, by means of which real-time determination of IDR from continuously changing effective surface areas of dissolving individual microparticles, is possible. The changing surface area of the individual microparticles is characterized through continuous random orientation 3D particle morphology characterization during the dissolution process. Using noninvasive optical monitoring and nonspecific image analysis, we determined IDRs of a diverse set of substances from individual pure-substance microparticles (14-747 μg) with an average relative standard deviation of 9.4%. A linear fit between SIDR and literature equilibrium solubility values (R(2) = 0.999) was achieved and kinetic solubility equivalent SIDRs were obtained, for all substances, in as little as 1 min. Such miniaturized methods could become valuable tools in drug discovery, by providing resource sparing higher quality data acquisition means to replace current high-throughput solubility methods.

  1. Developing dissolution testing methodologies for extended-release oral dosage forms with supersaturating properties. Case example: Solid dispersion matrix of indomethacin.

    PubMed

    Tajiri, Tomokazu; Morita, Shigeaki; Sakamoto, Ryosaku; Mimura, Hisahi; Ozaki, Yukihiro; Reppas, Christos; Kitamura, Satoshi

    2015-07-25

    The objective of this study was to develop an in vitro dissolution test method with discrimination ability for an extended-release solid dispersion matrix of a lipophilic drug using the United States Pharmacopeia (USP) Apparatus 4, flow-through cell apparatus. In the open-loop configuration, the sink condition was maintained by manipulating the flow rate of the dissolution medium. To evaluate the testing conditions, the drug release mechanism from an extended-release solid dispersion matrix containing hydrophobic and hydrophilic polymers was investigated. As the hydroxypropyl methylcellulose (HPMC) maintained concentrations of indomethacin higher than the solubility in a dissolution medium, the release of HPMC into the dissolution medium was also quantified using size-exclusion chromatography. We concluded that the USP Apparatus 4 is suitable for application to an in vitro dissolution method for orally administered extended-release solid dispersion matrix formulations containing poorly water-soluble drugs. PMID:26022889

  2. Developing dissolution testing methodologies for extended-release oral dosage forms with supersaturating properties. Case example: Solid dispersion matrix of indomethacin.

    PubMed

    Tajiri, Tomokazu; Morita, Shigeaki; Sakamoto, Ryosaku; Mimura, Hisahi; Ozaki, Yukihiro; Reppas, Christos; Kitamura, Satoshi

    2015-07-25

    The objective of this study was to develop an in vitro dissolution test method with discrimination ability for an extended-release solid dispersion matrix of a lipophilic drug using the United States Pharmacopeia (USP) Apparatus 4, flow-through cell apparatus. In the open-loop configuration, the sink condition was maintained by manipulating the flow rate of the dissolution medium. To evaluate the testing conditions, the drug release mechanism from an extended-release solid dispersion matrix containing hydrophobic and hydrophilic polymers was investigated. As the hydroxypropyl methylcellulose (HPMC) maintained concentrations of indomethacin higher than the solubility in a dissolution medium, the release of HPMC into the dissolution medium was also quantified using size-exclusion chromatography. We concluded that the USP Apparatus 4 is suitable for application to an in vitro dissolution method for orally administered extended-release solid dispersion matrix formulations containing poorly water-soluble drugs.

  3. EVALUATION OF ARG-1 SAMPLES PREPARED BY CESIUM CARBONATE DISSOLUTION DURING THE ISOLOK SME ACCEPTABILITY TESTING

    SciTech Connect

    Edwards, T.; Hera, K.; Coleman, C.

    2011-12-05

    Evaluation of Defense Waste Processing Facility (DWPF) Chemical Process Cell (CPC) cycle time identified several opportunities to improve the CPC processing time. The Mechanical Systems & Custom Equipment Development (MS&CED) Section of the Savannah River National Laboratory (SRNL) recently completed the evaluation of one of these opportunities - the possibility of using an Isolok sampling valve as an alternative to the Hydragard valve for taking DWPF process samples at the Slurry Mix Evaporator (SME). The use of an Isolok for SME sampling has the potential to improve operability, reduce maintenance time, and decrease CPC cycle time. The SME acceptability testing for the Isolok was requested in Task Technical Request (TTR) HLW-DWPF-TTR-2010-0036 and was conducted as outlined in Task Technical and Quality Assurance Plan (TTQAP) SRNLRP-2011-00145. RW-0333P QA requirements applied to the task, and the results from the investigation were documented in SRNL-STI-2011-00693. Measurement of the chemical composition of study samples was a critical component of the SME acceptability testing of the Isolok. A sampling and analytical plan supported the investigation with the analytical plan directing that the study samples be prepared by a cesium carbonate (Cs{sub 2}CO{sub 3}) fusion dissolution method and analyzed by Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP-OES). The use of the cesium carbonate preparation method for the Isolok testing provided an opportunity for an additional assessment of this dissolution method, which is being investigated as a potential replacement for the two methods (i.e., sodium peroxide fusion and mixed acid dissolution) that have been used at the DWPF for the analysis of SME samples. Earlier testing of the Cs{sub 2}CO{sub 3} method yielded promising results which led to a TTR from Savannah River Remediation, LLC (SRR) to SRNL for additional support and an associated TTQAP to direct the SRNL efforts. A technical report resulting

  4. Commercially available folic acid supplements and their compliance with the British Pharmacopoeia test for dissolution.

    PubMed

    Sculthorpe, N F; Davies, B; Ashton, T; Allison, S; McGuire, D N; Malhi, J S

    2001-09-01

    A recent report suggested that some folic acid preparations available in the United States failed to meet the specifications for dissolution specified by the US Pharmacopoeia (USP), of 70 per cent drug release in the first hour of testing. The Teratology Society recommends that women of childbearing age should take a daily supplement of 400 microg folic acid when they are trying to conceive, to reduce the risk of foetal neural tube defects. The consequence of this failure to meet the USP requirements may be that an inadequate dose of folate may be absorbed and thus the expected level of protection against neural tube defects not afforded. The purpose of the present study was to examine a number of brands of folic acid (400 microg), available commercially in the United Kingdom, for compliance with the British Pharmacopoeia (BP) test for dissolution. Ten tablets (or capsules) from each of 11 brands were tested using dissolution apparatus compliant with BP requirements, using 0.1 M sodium hydroxide as the dissolution medium. The results indicated that four of the brands failed to release 70 per cent of the nominal drug content in the first hour of test and thus did not comply with the test. Two of the seven brands that passed the test went on to release more than 150 per cent of the nominal 400 microg drug content. These results highlight the problems of dose uniformity and the potential health risks of slow dissolution and under-dosing in commercially available folic acid dosage forms.

  5. Development and Validation of a New HPLC Method for the Simultaneous Determination of Paracetamol, Ascorbic Acid, and Pseudoephedrine HCl in their Co-formulated Tablets. Application to in vitro Dissolution Testing.

    PubMed

    Ibrahim, Fawzia; El-Enany, Nahed; El-Shaheny, Rania N; Mikhail, Ibraam E

    2015-01-01

    The first HPLC method was developed for the simultaneous determination of paracetamol (PC), ascorbic acid (AA), and pseudoephedrine HCl (PE) in their co-formulated tablets. Separation was achieved on a C18 column in 5 min using a mobile phase composed of methanol-0.05 M phosphate buffer (35:65, v/v) at pH 2.5 with UV detection at 220 nm. Linear calibration curves were constructed over concentration ranges of 1.0 - 50.0, 3.0 - 60.0 and 3.0 - 80.0 μg mL(-1) for PC, AA, and PE, respectively. The method was validated and applied for the simultaneous determination of these drugs in their tablets with average % recoveries of 101.17 ± 0.67, 98.34 ± 0.77, and 98.95 ± 1.11%, for PC, AA, and PE, respectively. The proposed method was also used to construct in vitro dissolution profiles of the co-formulated tablets containing the three drugs.

  6. Dissolution profiles of perindopril and indapamide in their fixed-dose formulations by a new HPLC method and different mathematical approaches.

    PubMed

    Gumieniczek, Anna; Mączka, Paulina; Komsta, Łukasz; Pietraś, Rafał

    2015-09-01

    A new HPLC method was introduced and validated for simultaneous determination of perindopril and indapamide. Validation procedure included specificity, sensitivity, robustness, stability, linearity, precision and accuracy. The method was used for the dissolution test of perindopril and indapamide in three fixed-dose formulations. The dissolution procedure was optimized using different media, different pH of the buffer, surfactants, paddle speed and temperature. Similarity of dissolution profiles was estimated using different model-independent and model-dependent methods and, additionally, by principal component analysis (PCA). Also, some kinetic models were checked for dissolved amounts of drugs as a function of time. PMID:26431103

  7. Phase field and level set methods for modeling solute precipitation and/or dissolution

    SciTech Connect

    Zhijie Xu; Hai Huang; Paul Meakin

    2012-01-01

    The dynamics of solid-liquid interfaces controlled by solute precipitation and/or dissolution due to the chemical reaction at the interface were computed in two dimensions using a phase field models. Sharp-interface asymptotic analysis demonstrated that the phase field solutions should converge to the proper sharp-interface precipitation/dissolution limit. For the purpose of comparison, the numerical solution of the sharp-interface model for solute precipitation/dissolution was directly solved using a level set method. In general, the phase field results are found in good agreement with the level set results for all reaction rates and geometry configurations investigated. Present study supports the applications of both methods to more complicated and realistic reactive systems, including the nuclear waste release and mineral precipitation and dissolution

  8. Field test of a calcite dissolution rate law: Fort's Funnel Cave, Mammoth Cave National Park

    SciTech Connect

    Slunder, J.S. ); Groves, C.G. . Center for Cave and Karst Studies)

    1994-03-01

    The laboratory-derived calcite dissolution rate law of Plummer et al. (1978) is the most widely used and mechanistically detailed expression currently available for predicting dissolution rates as a function of water chemistry. Such rate expressions are of great use in understanding timescales associated with limestone karst development. Little work has gone into the field testing of the rate law under natural conditions. This work measured dissolution rates by a crystal weight loss experiment in Buffalo Creek within Fort's funnel Cave, which lies within a pristine, forested catchment of Mammoth Cave National Park. Continuous water chemistry sampling over the same period allowed a time-integrated prediction of the dissolution based on the Plummer et al. (1978) expression. Results indicate that the rate law overpredicted dissolution by a factor of about ten. This concurs with earlier laboratory work suggesting that the law tends to overpredict rates in solutions close to equilibrium with respect to calcite, as were the waters within this part of the groundwater flow system.

  9. Validation Testing of the Nitric Acid Dissolution Step Within the K Basin Sludge Pretreatment Process

    SciTech Connect

    AJ Schmidt; CH Delegard; KL Silvers; PR Bredt; CD Carlson; EW Hoppe; JC Hayes; DE Rinehart; SR Gano; BM Thornton

    1999-03-24

    The work described in this report involved comprehensive bench-scale testing of nitric acid (HNO{sub 3}) dissolution of actual sludge materials from the Hanford K East (KE) Basin to confirm the baseline chemical pretreatment process. In addition, process monitoring and material balance information was collected to support the development and refinement of process flow diagrams. The testing was performed by Pacific Northwest National Laboratory (PNNL)for the US Department of Energy's Office of Spent Fuel Stabilization (EM-67) and Numatec Hanford Corporation (NHC) to assist in the development of the K Basin Sludge Pretreatment Process. The baseline chemical pretreatment process for K Basin sludge is nitric acid dissolution of all particulate material passing a 1/4-in. screen. The acid-insoluble fraction (residual solids) will be stabilized (possibly by chemical leaching/rinsing and grouting), packaged, and transferred to the Hanford Environmental Restoration Disposal Facility (ERDF). The liquid fraction is to be diluted with depleted uranium for uranium criticality safety and iron nitrate for plutonium criticality safety, and neutralized with sodium hydroxide. The liquid fraction and associated precipitates are to be stored in the Hanford Tank Waste Remediation Systems (TWRS) pending vitrification. It is expected that most of the polychlorinated biphenyls (PCBs), associated with some K Basin sludges, will remain with the residual solids for ultimate disposal to ERDF. Filtration and precipitation during the neutralization step will further remove trace quantities of PCBs within the liquid fraction. The purpose of the work discussed in this report was to examine the dissolution behavior of actual KE Basin sludge materials at baseline flowsheet conditions and validate the.dissolution process step through bench-scale testing. The progress of the dissolution was evaluated by measuring the solution electrical conductivity and concentrations of key species in the dissolver

  10. A novel dissolution media for testing drug release from a nanostructured polysaccharide-based colon specific drug delivery system: an approach to alternative colon media.

    PubMed

    Kotla, Niranjan G; Singh, Sima; Maddiboyina, Balaji; Sunnapu, Omprakash; Webster, Thomas J

    2016-01-01

    The aim of this study was to develop a novel microbially triggered and animal-sparing dissolution method for testing of nanorough polysaccharide-based micron granules for colonic drug delivery. In this method, probiotic cultures of bacteria present in the colonic region were prepared and added to the dissolution media and compared with the performance of conventional dissolution methodologies (such as media with rat cecal and human fecal media). In this study, the predominant species (such as Bacteroides, Bifidobacterium, Lactobacillus species, Eubacterium and Streptococcus) were cultured in 12% w/v skimmed milk powder and 5% w/v grade "A" honey. Approximately 10(10)-10(11) colony forming units m/L of probiotic culture was added to the dissolution media to test the drug release of polysaccharide-based formulations. A USP dissolution apparatus I/II using a gradient pH dissolution method was used to evaluate drug release from formulations meant for colonic drug delivery. Drug release of guar gum/Eudragit FS30D coated 5-fluorouracil granules was assessed under gastric and small intestine conditions within a simulated colonic environment involving fermentation testing with the probiotic culture. The results with the probiotic system were comparable to those obtained from the rat cecal and human fecal-based fermentation model, thereby suggesting that a probiotic dissolution method can be successfully applied for drug release testing of any polysaccharide-based oral formulation meant for colonic delivery. As such, this study significantly adds to the nanostructured biomaterials' community by elucidating an easier assay for colonic drug delivery. PMID:27051284

  11. A novel dissolution media for testing drug release from a nanostructured polysaccharide-based colon specific drug delivery system: an approach to alternative colon media

    PubMed Central

    Kotla, Niranjan G; Singh, Sima; Maddiboyina, Balaji; Sunnapu, Omprakash; Webster, Thomas J

    2016-01-01

    The aim of this study was to develop a novel microbially triggered and animal-sparing dissolution method for testing of nanorough polysaccharide-based micron granules for colonic drug delivery. In this method, probiotic cultures of bacteria present in the colonic region were prepared and added to the dissolution media and compared with the performance of conventional dissolution methodologies (such as media with rat cecal and human fecal media). In this study, the predominant species (such as Bacteroides, Bifidobacterium, Lactobacillus species, Eubacterium and Streptococcus) were cultured in 12% w/v skimmed milk powder and 5% w/v grade “A” honey. Approximately 1010–1011 colony forming units m/L of probiotic culture was added to the dissolution media to test the drug release of polysaccharide-based formulations. A USP dissolution apparatus I/II using a gradient pH dissolution method was used to evaluate drug release from formulations meant for colonic drug delivery. Drug release of guar gum/Eudragit FS30D coated 5-fluorouracil granules was assessed under gastric and small intestine conditions within a simulated colonic environment involving fermentation testing with the probiotic culture. The results with the probiotic system were comparable to those obtained from the rat cecal and human fecal-based fermentation model, thereby suggesting that a probiotic dissolution method can be successfully applied for drug release testing of any polysaccharide-based oral formulation meant for colonic delivery. As such, this study significantly adds to the nanostructured biomaterials’ community by elucidating an easier assay for colonic drug delivery. PMID:27051284

  12. A new NMR method for directly monitoring and quantifying the dissolution kinetics of starch in DMSO.

    PubMed

    Dona, Anthony; Yuen, Chun-Wai Wayne; Peate, Jonathan; Gilbert, Robert G; Castignolles, Patrice; Gaborieau, Marianne

    2007-12-10

    The kinetics of dissolution of starch is needed for (i) understanding digestive processes; (ii) providing data that could correlate with higher levels of starch structure; (iii) improving techniques for starch characterization in solution. A novel method is presented here to directly monitor these dissolution kinetics by time-resolved (1)H solution-state nuclear magnetic resonance (NMR); studies were carried out in deuterated dimethyl sulfoxide (DMSO-d(6)). By assuming pseudo-first-order kinetics with respect to starch concentration, the data for various starch samples yield values of the apparent rate coefficients for the rate of appearance of completely dissolved anhydroglucose units, results which have not been obtained hitherto. The presence of a limited amount of water in DMSO had a drastic effect on dissolution kinetics (slowing it down at high temperatures), indicating multiple pathways for the dissolution mechanism. Dynamic light scattering (DLS) appears to be more limited than the NMR method to monitor the kinetics of dissolution. The newly developed NMR method can be extended to other solvents and polysaccharides. PMID:17892866

  13. Theoretical Investigation of Dissolution Test Criteria for Waiver of Clinical Bioequivalence Study.

    PubMed

    Sugano, Kiyohiko

    2016-06-01

    The purpose of the present study was to provide a theoretical basis for the dissolution test criteria of a biowaiver scheme. The critical dissolution number (Dncrit) was defined as a value to show bioequivalence of AUC and Cmax against infinitely rapid dissolution (Dn = ∞). The gastrointestinal tract was represented by the one-compartment model. The dissolution of a drug was expressed by the Noyes-Whitney equation. The permeation of a drug was expressed by the first-order equation. The approximate analytical solutions of Dncrit were derived from the analytical solution for the fraction of a dose absorbed [Fa = 1 - exp(-1/(1/Dn + Do/Pn)]; Do, the dose number; Pn, the permeation number). Numerical integration was also performed to calculate Dncrit more accurately. Dncrit was found to become smaller as Pn and Do became smaller. Dncrit for Cmax was found to be dependent on the elimination half-life of a drug as well as Pn and Do. The Fa equation can be an appropriate theoretical basis for a biowaiver scheme. PMID:27238491

  14. Theoretical Investigation of Dissolution Test Criteria for Waiver of Clinical Bioequivalence Study.

    PubMed

    Sugano, Kiyohiko

    2016-06-01

    The purpose of the present study was to provide a theoretical basis for the dissolution test criteria of a biowaiver scheme. The critical dissolution number (Dncrit) was defined as a value to show bioequivalence of AUC and Cmax against infinitely rapid dissolution (Dn = ∞). The gastrointestinal tract was represented by the one-compartment model. The dissolution of a drug was expressed by the Noyes-Whitney equation. The permeation of a drug was expressed by the first-order equation. The approximate analytical solutions of Dncrit were derived from the analytical solution for the fraction of a dose absorbed [Fa = 1 - exp(-1/(1/Dn + Do/Pn)]; Do, the dose number; Pn, the permeation number). Numerical integration was also performed to calculate Dncrit more accurately. Dncrit was found to become smaller as Pn and Do became smaller. Dncrit for Cmax was found to be dependent on the elimination half-life of a drug as well as Pn and Do. The Fa equation can be an appropriate theoretical basis for a biowaiver scheme.

  15. Hydroxyapatite, fluor-hydroxyapatite and fluorapatite produced via the sol-gel method: dissolution behaviour and biological properties after crystallisation.

    PubMed

    Tredwin, Christopher J; Young, Anne M; Abou Neel, Ensanya A; Georgiou, George; Knowles, Jonathan C

    2014-01-01

    Hydroxyapatite (HA), fluor-hydroxyapatite (FHA) with varying levels of fluoride ion substitution and fluorapatite (FA) were synthesised by the sol-gel method as possible implant coating or bone-grafting materials. Calcium nitrate and triethyl phosphite were used as precursors under an ethanol-water based solution. Different amounts of ammonium fluoride were incorporated for the preparation of the FHA and FA sol-gels. After heating and powdering the sol-gels, dissolution behaviour was assessed using ion chromatography to measure Ca(2+) and PO4 (3-) ion release. Biological behaviour was assessed using cellular proliferation with human osteosarcoma cells and alamarBlue™ assay. Statistical analysis was performed with a two way analysis of variance and post hoc testing with a Bonferroni correction. Increasing fluoride substitution into an apatite structure decreased the dissolution rate. Increasing the firing temperature of the HA, FHA and FA sol-gels up to 1,000 °C decreased the dissolution rate. There was significantly higher cellular proliferation on highly substituted FHA and FA than on HA or Titanium. The properties of an implant coating or bone grafting material can be tailored to meet specific requirements by altering the amount of fluoride that is incorporated into the original apatite structure. The dissolution behaviour can further be altered by the temperature at which the sol-gel is fired.

  16. Evaluation of the Microcentrifuge Dissolution Method as a Tool for Spray-Dried Dispersion.

    PubMed

    Wu, Benjamin; Li, Jinjiang; Wang, Yahong

    2016-03-01

    Although using spray-dried dispersions (SDDs) to improve the bioavailability of poorly water-soluble compounds has become a common practice in supporting the early phases of clinical studies, their performance evaluation, whether in solid dosage forms or alone, still presents significant challenges. A microcentrifuge dissolution method has been reported to quickly assess the dissolution performance of SDDs. While the microcentrifuge dissolution method has been used in the SDD community, there is still a need to understand the mechanisms about the molecular species present in supernatant after centrifugation, the molecular nature of active pharmaceutical ingredients (APIs), as well as the impact of experimental conditions. In this paper, we aim to assess the effect of API and polymer properties on the dissolution behavior of SDDs along with centrifuging parameters, and for this, two poorly water-soluble compounds (indomethacin and ketoconazole) and two commonly used polymers in the pharmaceutical industry (PVP and HPMC-AS) were chosen to prepare SDDs. A typical microcentrifuge dissolution procedure as reported in the publication (Curatolo et al., Pharm Res 26:1419-1431, 2009) was followed. In addition, after separation of the supernatant from precipitation, some of the samples were filtered through filters of various sizes to investigate the particulate nature (particle size) of the supernatant. Furthermore, the centrifuge speed was varied to study sedimentation of API, SDD, or polymer particles. The results indicated that for the SDDs of four drug-polymer pairs, microcentrifuge dissolution exhibited varied behaviors, depending on the polymer and the drug used. The SDDs of indomethacin with either PVP or HPMC-AS showed a reproducible dissolution with minimum variability even after filtration and subjecting to varied centrifugation speed, suggesting that the supernatant behaved solution-like. However, ketoconazole-PVP and ketoconazole-HPMC-AS SDDs displayed a

  17. Investigation of a suitable in vitro dissolution test for itraconazole-based solid dispersions.

    PubMed

    Thiry, Justine; Broze, Guy; Pestieau, Aude; Tatton, Andrew S; Baumans, France; Damblon, Christian; Krier, Fabrice; Evrard, Brigitte

    2016-03-31

    The difficulty to find a relevant in vitro dissolution test to evaluate poorly soluble drugs is a well-known issue. One way to enhance their aqueous solubility is to formulate them as amorphous solid dispersions. In this study, three formulations containing itraconazole (ITZ), a model drug, were tested in seven different conditions (different USP apparatuses and different media). Two of the formulations were amorphous solid dispersions namely Sporanox®, the marketed product, and extrudates composed of Soluplus® and ITZ produced by hot melt extrusion; and the last one was pure crystalline ITZ capsules. After each test, a ranking of the formulations was established. Surprisingly, the two amorphous solid dispersions exhibited very different behavior depending primarily on the dissolution media. Indeed, the extrudates showed a better release profile than Sporanox® in non-sink and in biphasic conditions, whilst Sporanox® showed a higher release profile than the extrudates in sink and fasted simulated gastric conditions. The disintegration, dynamic light scattering and nuclear magnetic resonance results highlighted the presence of interaction between the surfactants and Soluplus®, which slowed down the erosion of the polymer matrix. Indeed, the negative charge of sodium dodecyl sulfate (SDS) and bile salts interacted with the surface of the extrudates that formed a barrier through which the water hardly diffused. Moreover, Soluplus® and SDS formed mixed micelles in solution in which ITZ interacts with SDS, but no longer with Soluplus®. Regarding the biphasic dissolution test, the interactions between the octanol dissolved in the aqueous media disrupted the polymer--ITZ system leading to a reduced release of ITZ from Sporanox®, whilst it had no influence on the extrudates. All together these results pointed out the difficulty of finding a suitable in vitro dissolution test due to interactions between the excipients that complicates the prediction of the behavior

  18. Production and dissolution of nuclear explosive melt glasses at underground test sites in the Pacific Region

    SciTech Connect

    Bourcier, W.L.; Smith, D.K.

    1998-11-06

    From 1975 to 1996 the French detonated 140 underground nuclear explosions beneath the atolls of Mururoa and Fangataufa in the South Pacific; from 1965 to 1971 the United States detonated three high yield nuclear tests beneath Amchitka Island in the Aleutian chain. Approximately 800 metric tons of basalt is melted per kiloton of nuclear yield; almost lo7 metric tons of basalt were melted in these tests. Long-lived and toxic radionuclides are partitioned into the melt glass at the time of explosion and are released by dissolution with seawater under saturated conditions. A glass dissolution model predicts that nuclear melt glasses at these sites will dissolve in lo6 to lo7 yea

  19. Phase field and level set methods for modeling solute precipitation and/or dissolution

    SciTech Connect

    Xu, Zhijie; Huang, Hai; Li, Xiaoyi; Meakin, Paul

    2012-01-02

    The dynamics of solid-liquid interfaces controlled by solute precipitation and/or dissolution due to the chemical reaction at the interface were computed in two dimensions using a phase field models. Sharp-interface asymptotic analysis demonstrated that the phase field solutions should converge to the proper sharp-interface precipitation/dissolution limit. For the purpose of comparison, the numerical solution of the sharp-interface model for solute precipitation/dissolution was directly solved using a level set method. In general, the phase field results are found in good agreement with the level set results for all reaction rates and geometry configurations. Present study supports the applications of both methods to more complicated and realistic reactive systems.

  20. Method for dissolution and stabilization of silica-rich fibers

    DOEpatents

    Jantzen, Carol M.

    1997-01-01

    A method for dissolving silica-rich fibers such as borosilicate fibers, fiberglass and asbestos to stabilize them for disposal. The method comprises (1) immersing the fibers in hot, five-weight-percent sodium hydroxide solution until the concentration of dissolved silica reaches equilibrium and a only a residue is left (about 48 hours), then immersing the residue in hot, five-weight-percent nitric acid until the residue dissolves (about 96 hours). After adjusting the pH of the dissolved fibers to be caustic, the solution can then be added to a waste vitrification stream for safe disposal. The method is useful in disposing contaminated HEME and HEPA filters.

  1. Experimental and computational determination of the hydrodynamics of mini vessel dissolution testing systems.

    PubMed

    Wang, Bing; Armenante, Piero M

    2016-08-20

    Mini vessel dissolution testing systems consist of a small-scale 100-mL vessel with a small paddle impeller, similar to the USP Apparatus 2, and are typically utilized when only small amounts of drug product are available during drug development. Despite their common industrial use, mini vessels have received little attention in the literature. Here, Computational Fluid Dynamics (CFD) was used to predict velocity profiles, flow patterns, and strain rate distribution in a mini vessel at different agitation speeds. These results were compared with experimental velocity measurements obtained with Particle Image Velocimetry (PIV). Substantial agreement was observed between CFD results and PIV data. The flow is strongly dominated by the tangential velocity component. Secondary flows consist of vertical upper and lower recirculation loops above and below the impeller. A low recirculation zone was observed in the lower part of the vessel. The radial and axial velocities in the region just below the impeller are very small especially in the innermost core zone below the paddle, where tablet dissolution occurs. Increasing agitation speed reduces the radius of this zone, which is always present at any speed, and only modestly increases the tangential flow intensity, with significant implication for dissolution testing in mini vessels. PMID:27317988

  2. Experimental and computational determination of the hydrodynamics of mini vessel dissolution testing systems.

    PubMed

    Wang, Bing; Armenante, Piero M

    2016-08-20

    Mini vessel dissolution testing systems consist of a small-scale 100-mL vessel with a small paddle impeller, similar to the USP Apparatus 2, and are typically utilized when only small amounts of drug product are available during drug development. Despite their common industrial use, mini vessels have received little attention in the literature. Here, Computational Fluid Dynamics (CFD) was used to predict velocity profiles, flow patterns, and strain rate distribution in a mini vessel at different agitation speeds. These results were compared with experimental velocity measurements obtained with Particle Image Velocimetry (PIV). Substantial agreement was observed between CFD results and PIV data. The flow is strongly dominated by the tangential velocity component. Secondary flows consist of vertical upper and lower recirculation loops above and below the impeller. A low recirculation zone was observed in the lower part of the vessel. The radial and axial velocities in the region just below the impeller are very small especially in the innermost core zone below the paddle, where tablet dissolution occurs. Increasing agitation speed reduces the radius of this zone, which is always present at any speed, and only modestly increases the tangential flow intensity, with significant implication for dissolution testing in mini vessels.

  3. Method for dissolution and stabilization of silica-rich fibers

    DOEpatents

    Jantzen, C.M.

    1997-11-11

    A method is described for dissolving silica-rich fibers such as borosilicate fibers, fiberglass and asbestos to stabilize them for disposal. The method comprises (1) immersing the fibers in hot, five-weight-percent sodium hydroxide solution until the concentration of dissolved silica reaches equilibrium and a only a residue is left (about 48 hours), then immersing the residue in hot, five-weight-percent nitric acid until the residue dissolves (about 96 hours). After adjusting the pH of the dissolved fibers to be caustic, the solution can then be added to a waste vitrification stream for safe disposal. The method is useful in disposing contaminated HEME and HEPA filters. 1 fig.

  4. Novel silk fibroin films prepared by formic acid/hydroxyapatite dissolution method.

    PubMed

    Ming, Jinfa; Liu, Zhi; Bie, Shiyu; Zhang, Feng; Zuo, Baoqi

    2014-04-01

    Bombyx mori silk fibroin from the silkworm was firstly found to be soluble in formic acid/hydroxyapatite system. The rheological behavior of silk fibroin solution was significantly influenced by HAp contents in dissolved solution. At the same time, silk fibroin nanofibers were observed in dissolved solution with 103.6±20.4nm in diameter. Moreover, the structure behavior of SF films prepared by formic acid/hydroxyapatite dissolution method was examined. The secondary structure of silk fibroin films was attributed to silk II structure (β-sheet), indicating that the hydroxyapatite contents in dissolved solution were not significantly affected by the structure of silk fibroin. The X-ray diffraction results exhibited obviously hydroxyapatite crystalline nature existing in silk fibroin films; however, when the hydroxyapatite content was 5.0wt.% in dissolved solution, some hydroxyapatite crystals were converted to calcium hydrogen phosphate dehydrate in silk fibroin dissolution process. This result was also confirmed by Fourier transform infrared analysis and DSC measurement. In addition, silk fibroin films prepared by this dissolution method had higher breaking strength and extension at break. Based on these analyses, an understanding of novel SF dissolution method may provide an additional tool for designing and synthesizing advanced materials with more complex structures, which should be helpful in different fields, including biomaterial applications.

  5. Single-step preparation and deagglomeration of itraconazole microflakes by supercritical antisolvent method for dissolution enhancement.

    PubMed

    Sathigari, Sateesh Kumar; Ober, Courtney A; Sanganwar, Ganesh P; Gupta, Ram B; Babu, R Jayachandra

    2011-07-01

    Itraconazole (ITZ) microflakes were produced by supercritical antisolvent (SAS) method and simultaneously mixed with pharmaceutical excipients in a single step to prevent drug agglomeration. Simultaneous ITZ particle formation and mixing with fast-flo lactose (FFL) was performed in a high-pressure stirred vessel at 116 bar and 40 °C by the SAS-drug excipient mixing (SAS-DEM) method. The effects of stabilizers, such as sodium dodecyl sulfate and poloxamer 407 (PLX), on particle formation and drug dissolution were studied. Drug-excipient formulations were characterized for surface morphology, crystallinity, drug-excipient interactions, drug content uniformity, and drug dissolution rate. Mixture of drug microflakes and FFL formed by the SAS-DEM process shows that the process was successful in overcoming drug-drug agglomeration. PLX produced crystalline drug flakes in loose agglomerates with superior dissolution and flow properties even at higher drug loadings. Characterization studies confirmed the crystallinity of the drug and absence of chemical interactions during the SAS process. The dissolution of ITZ was substantially higher due to SAS and SAS-DEM processes; this improvement can be attributed to the microflake particle structures, effective deagglomeration, and wetting of the drug flakes with the excipients.

  6. Results from Nevada Nuclear Waste Storage Investigations (NNWSI) Series 3 spent fuel dissolution tests

    SciTech Connect

    Wilson, C.N.

    1990-06-01

    The dissolution and radionuclide release behavior of spent fuel in groundwater is being studied by the Yucca Mountain Project (YMP), formerly the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. Specimens prepared from pressurized water reactor fuel rod segments were tested in sealed stainless steel vessels in Nevada Test Site J-13 well water at 85{degree}C and 25{degree}C. The test matrix included three specimens of bare-fuel particles plus cladding hulls, two fuel rod segments with artificially defected cladding and water-tight end fittings, and an undefected fuel rod section with watertight end fittings. Periodic solution samples were taken during test cycles with the sample volumes replenished with fresh J-13 water. Test cycles were periodically terminated and the specimens restarted in fresh J-13 water. The specimens were run for three cycles for a total test duration of 15 months. 22 refs., 32 figs., 26 tabs.

  7. CO2CRC's Otway Residual Saturation and Dissolution Test: Using Reactive Ester Tracers to Determine Residual CO2 Saturation

    NASA Astrophysics Data System (ADS)

    Myers, M.; Stalker, L.; LaForce, T.; Pejcic, B.; Dyt, C.; Ho, K.; Ennis-King, J.

    2013-12-01

    oil saturation and the second is based on TOUGH2. The estimates of residual saturation given by these models were similar giving a very low residual CO2 saturation value. We suspect that this low value might be due to CO2 being inadvertently dissolved in the near wellbore region prior to this test. This possible dissolution of CO2 may be attributed to the complexity of the multi-test sequence (including other tracer tests prior to this particular test) used in the overall program at of the Residual Gas Saturation and Dissolution Test. References Myers, M., Stalker, L., Ross, A., Dyt, C., Ho, K.-B., 2012. Method for the determination of residual carbon dioxide saturation using reactive ester tracers. Applied Geochemistry 27, 2148-2156.

  8. pH-metric solubility. 3. Dissolution titration template method for solubility determination.

    PubMed

    Avdeef, A; Berger, C M

    2001-12-01

    The main objective of this study was to develop an effective potentiometric saturation titration protocol for determining the aqueous intrinsic solubility and the solubility-pH profile of ionizable molecules, with the specific aim of overcoming incomplete dissolution conditions, while attempting to shorten the data collection time. A modern theory of dissolution kinetics (an extension of the Noyes-Whitney approach) was applied to acid-base titration experiments. A thermodynamic method was developed, based on a three-component model, to calculate interfacial, diffusion-layer, and bulk-water reactant concentrations in saturated solutions of ionizable compounds perturbed by additions of acid/base titrant, leading to partial dissolution of the solid material. Ten commercial drugs (cimetidine, diltiazem hydrochloride, enalapril maleate, metoprolol tartrate, nadolol, propoxyphene hydrochloride, quinine hydrochloride, terfenadine, trovafloxacin mesylate, and benzoic acid) were chosen to illustrate the new titration methodology. It was shown that the new method is about 10 times faster in determining equilibrium solubility constants, compared to the traditional saturation shake-flask methods.

  9. K Basin Sludge Conditioning Testing Nitric Acid Dissolution Testing of K East Area Sludge Composite, Small- and Large-Scale Testing

    SciTech Connect

    Carlson, C.D.; Delegard, C.H.; Burgeson, I.E.; Schmidt, A.J.; Silvers, K.L.

    1999-04-02

    This report describes work performed by Pacific Northwest National Laboratory (PNNL) for Numatec Hanford Corporation (NHC) to support the development of the K Basin Sludge Treatment System. For this work, testing was performed to examine the dissolution behavior of a K East Basin floor and Weasel Pit sludge composite, referred to as K East area sludge composite, in nitric acid at the following concentrations: 2 M, 4 M, 6 M and 7.8 M. With the exception of one high solids loading test the nitric acid was added at 4X the stoichiometric requirement (assuming 100% of the sludge was uranium metal). The dissolution tests were conducted at boiling temperatures for 24 hours. Most of the tests were conducted with {approximately}2.5 g of sludge (dry basis). The high solids loading test was conducted with {approximately}7 g of sludge. A large-scale dissolution test was conducted with 26.5 g of sludge and 620 mL of 6 M nitric acid. The objectives of this test were to (1) generate a sufficient quantity of acid-insoluble residual solids for use in leaching studies, and (2) examine the dissolution behavior of the sludge composite at a larger scale.

  10. Method for improving dissolution efficiency in gas-absorption and liquid extraction processes. [Patent application

    DOEpatents

    Kanak, B.E.; Stephenson, M.J.

    1980-01-11

    A method is described for improving dissolution efficiency in processes in which a feed fluid is introduced to a zone where it is contacted with a liquid solvent for preferentially removing a component of the feed and where part of the solvent so contacted undergoes transfer into the feed fluid to saturate the same. It has been found that such transfer significantly impairs dissolution efficiency. In accordance with the invention, an amount of the above-mentioned solvent is added to the feed fluid being introduced to the contact zone, the solvent being added in an amount sufficient to effect reduction or elimination of the above-mentioned transfer. Preferably, the solvent is added to the feed fluid in an amount saturating or supersaturating the feed fluid under the conditions prevailing in the contact zone.

  11. Method for improving dissolution efficiency in gas-absorption and liquid extraction processes

    DOEpatents

    Kanak, Brant E.; Stephenson, Michael J.

    1981-01-01

    This invention is a method for improving dissolution efficiency in processes in which a feed fluid is introduced to a zone where it is contacted with a liquid solvent for preferentially removing a component of the feed and where part of the solvent so contacted undergoes transfer into the feed fluid to saturate the same. It has been found that such transfer significantly impairs dissolution efficiency. In accordance with the invention, an amount of the above-mentioned solvent is added to the feed fluid being introduced to the contact zone, the solvent being added in an amount sufficient to effect reduction or elimination of the above-mentioned transfer. Preferably, the solvent is added to the feed fluid in an amount saturating or supersaturating the feed fluid under the conditions prevailing in the contact zone.

  12. Dissolution behavior of Caldag lateritic nickel ore subjected to a sequential organic acid leaching method

    NASA Astrophysics Data System (ADS)

    Kursunoglu, Sait; Kaya, Muammer

    2015-11-01

    The dissolution behavior of Caldag lateritic nickel ore subjected to a sequential organic acid leaching method was investigated. The effects of the type of organic acid, acid concentration, leaching time, and leaching temperature on the lateritic nickel ore were examined. Organic acids were used individually prior to sequential leaching. Citric acid was more effective than the other two acids for the selective leaching of nickel and cobalt. An increase in the citric acid concentration negligibly affected the dissolution of the metals, whereas temperature exhibited a strong beneficial effect. Oxalic acid was determined to be the most appropriate organic acid for the second leaching step. After 8 h (4 h + 4 h) of leaching with organic acids (0.5 M citric + 0.5 M oxalic) in sequence at 90°C, 89.63% Ni, 82.89% Co, and 69.63% Fe were leached from the lateritic nickel ore. A sequential citric + oxalic acid leaching method could represent a viable alternative for the dissolution of metals from lateritic nickel ore.

  13. Results from NNWSI [Nevada Nuclear Waste Storage Investigations] Series 2 bare fuel dissolution tests

    SciTech Connect

    Wilson, C.N.

    1990-09-01

    The dissolution and radionuclide release behavior of spent fuel in groundwater is being studied by the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. Two bare spent fuel specimens plus the empty cladding hulls were tested in NNWSI J-13 well water in unsealed fused silica vessels under ambient hot cell air conditions (25{degree}C) in the currently reported tests. One of the specimens was prepared from a rod irradiated in the H. B. Robinson Unit 2 reactor and the other from a rod irradiated in the Turkey Point Unit 3 reactor. Results indicate that most radionuclides of interest fall into three groups for release modeling. The first group principally includes the actinides (U, Np, Pu, Am, and Cm), all of which reached solubility-limited concentrations that were orders of magnitude below those necessary to meet the NRC 10 CFR 60.113 release limits for any realistic water flux predicted for the Yucca Mountain repository site. The second group is nuclides of soluble elements such as Cs, Tc, and I, for which release rates do not appear to be solubility-limited and may depend on the dissolution rate of fuel. In later test cycles, {sup 137}Cs, {sup 90}Sr, {sup 99}Tc, and {sup 129}I were continuously released at rates between about 5 {times} 10{sup {minus}5} and 1 {times} 10{sup {minus}4} of inventory per year. The third group is radionuclides that may be transported in the vapor phase, of which {sup 14}C is of primary concern. Detailed test results are presented and discussed. 17 refs., 15 figs., 21 tabs.

  14. Selective chemical dissolution of sulfides: An evaluation of six methods applicable to assaying sulfide-bound nickel

    USGS Publications Warehouse

    Klock, P.R.; Czamanske, G.K.; Foose, M.; Pesek, J.

    1986-01-01

    Six analytical techniques for the selective chemical dissolution of sulfides are compared with the purpose of defining the best method for accurately determining the concentration of sulfide-bound nickel. Synthesized sulfide phases of known elemental content, mixed with well-analyzed silicates, were used to determine the relative and absolute efficiency, based on Ni and Mg recovery, of the techniques. Tested leach-methods purported to dissolve sulfide from silicate phases include: brominated water, brominated water-carbon tetrachloride, nitric-hydrochloric acid, hydrogen peroxide-ammonium citrate, bromine-methanol and hydrogen peroxide-ascorbic acid. Only the hydrogen peroxide-ammonium citrate method did not prove adequate in dissolving the sulfide phases. The remaining five methods dissolved the sulfide phases, but the indicated amount of attack on the silicate portion ranged from 3% to 100%. The bromine-methanol method is recommended for assaying sulfide-Ni deposits when Ni is also present in silicate phases. ?? 1986.

  15. Dissolution Behaviour of Hazardous Materials from Steel Slag with Wet Grinding Method

    NASA Astrophysics Data System (ADS)

    Hisyamudin Muhd Nor, Nik; Norhana Selamat, Siti; Hanif Abd Rashid, Muhammad; Fauzi Ahmad, Mohd; Jamian, Saifulnizan; Chee Kiong, Sia; Fahrul Hassan, Mohd; Mohamad, Fariza; Yokoyama, Seiji

    2016-06-01

    Steel slag is a by-product from steel industry and it contains variety of hazardous materials. In this study, the dissolution behaviour and removal potential of hazardous materials from steel slag with the wet grinding method was investigated. The slag was wet ground in the CO2 atmosphere and the slurry produced was filtered using centrifugal separator to separate the liquid and solid sediments. Then, the concentrations of dissolved metal elements in the liquid sediment were analyzed by ICP-MS. The changes of pH during the grinding were also investigated. It was found that the pHs were decreased immediately after the CO2 gas introduced into the vessel. The pHs were ranging from 6.8 to 7.6 at the end of grinding. The dissolved concentration of Zn and Cr were ranging from 5~45 [mg/dm3] and 0.2~2.5 [mg/dm3] respectively. The ratios of Zn removal for stainless steel oxidizing and reducing slag were very high, but those from normal steel oxidizing and reducing slag were very low. It is assumed that the Zn dissolved as ZnOH+ from Zn(OH)2 that formed due to the reaction between ZnO and water. Dissolution of Cr also occurred but in very low quantity compared to the dissolution of Zn. The dissolution of Cr occurred due to the grinding process and small amount of Cr(OH)3 was formed during the grinding. This small formation of Cr(OH)3 resulted to the low dissolved concentration of Cr in the form of Cr(OH)2+. According to the XRD analysis, the Cr mostly existed in the slags as Cr(IIl) in the form of MgCr2O4 and FeCr2O4.

  16. In vitro release of ketoprofen suppositories using the USP basket and the flow-through cell dissolution methods.

    PubMed

    Medina, José Raúl; Padilla, Adrián Roberto; Hurtado, Marcela; Cortés, Alma Rosa; Domínguez-Ramírez, Adriana Miriam

    2014-05-01

    In order to study the release characteristics of ketoprofen suppositories under the hydrodynamic environment generated by USP Apparatus 1 and 4, the dissolution profiles of the Mexican reference product (100 mg) were determined. Phosphate buffer pH 8 and 1% sodium lauryl sulfate (SLS) aqueous solutions were proved as dissolution mediums. Baskets were rotated at 100 rpm with USP Apparatus 1 and different flow rates from 16-32 mL/min with USP Apparatus 4 were used. Drug samples were taken and quantified during 60 min by UV analysis at 260 nm. Mean dissolution time (MDT) and dissolution efficiency (DE) were calculated by model-independent methods. Data were also fitted to several kinetic models. Poor dissolution was found in both dissolution mediums when USP basket method was used (< 10% dissolved) while better results were obtained with USP Apparatus 4 when 1% SLS at 24 mL/min was used (43.6% dissolved, MDT of 25.5 min and DE of 25.0%). Kinetics showed a great variability when the USP Apparatus 1 was used, and Gompertz fitted well for data of 1% SLS at 24 mL/min (R(2)(adjusted) > 0.99). The results suggest the need to establish an adequate dissolution method to evaluate the release kinetics of ketoprofen from suppositories.

  17. Development and validation of a dissolution test for a once-a-day combination tablet of immediate-release cetirizine dihydrochloride and extended-release pseudoephedrine hydrochloride.

    PubMed

    Likar, Michael D; Mansour, Hany L; Harwood, Jeffrey W

    2005-09-15

    A dissolution test for a once daily combination tablet containing 10 mg of cetirizine dihydrochloride (cetirizine HCl) for immediate release and 240 mg of pseudoephedrine hydrochloride (pseudoephedrine HCl) for extended release was developed and validated according to current ICH and FDA guidelines. The cetirizine HCl is contained within an outer layer of the tablet while a semipermeable membrane of cellulose acetate and polyethylene glycol controls the rate at which pseudoephedrine HCl is released from the tablet core. The dissolution method, which uses USP apparatus 2 with paddles rotating at 50 rpm, 1000 ml of deaerated water as the dissolution medium, and reversed-phased HPLC for quantitation, was demonstrated to be robust, discriminating, and transferable. These test conditions were selected after it was demonstrated that the cetirizine HCl portion of the tablet rapidly dissolved in aqueous media over the physiologically relevant pH range of 1.1-7.5, and that the extended-release profile of pseudoephedrine HCl was independent of dissolution conditions (i.e., apparatus, pH, and agitation).

  18. Dissolution and particle size characterization of radioactive contaminants in Hanford facilities: Criteria for methods of measurement

    SciTech Connect

    Briant, J.K.; James, A.C.

    1990-08-01

    The purpose of this document is to discuss experimental methods that can be applied to evaluate the rate at which an actinide material is likely to dissolve in biological fluids. Criteria are recommended for the design and conduct of meaningful experimental procedures to sample a representative size fraction of the source material, to measure the rate of radionuclide dissolution, and to apply the results to assign the material to an appropriate ICRP Publication-30 lung retention class (or mixture of classes). 26 refs., 3 figs., 3 tabs.

  19. TRANSPORT OF REACTING SOLUTES SUBJECT TO A MOVING DISSOLUTION BOUNDARY: NUMERICAL METHODS AND SOLUTIONS.

    USGS Publications Warehouse

    Willis, Catherine; Rubin, Jacob

    1987-01-01

    In this paper we consider examples of chemistry-affected transport processes in porous media. A moving boundary problem which arises during transport with precipitation-dissolution reactions is solved by three different numerical methods. Two of these methods (one explicit and one implicit) are based on an integral formulation of mass balance and lead to an approximation of a weak solution. These methods are compared to a front-tracking scheme. Although the two approaches are conceptually different, the numerical solutions showed good agreement. As the ratio of dispersion to convection decreases, the methods based on the integral formulation become computationally more efficient. Specific reactions were modeled to examine the dependence of the system on the physical and chemical parameters.

  20. Recovery of waterborne oocysts of Cryptosporidium from water samples by the membrane-filter dissolution method.

    PubMed

    Graczyk, T K; Cranfield, M R; Fayer, R

    1997-01-01

    The cellulose-acetate membrane (CAM)-filter dissolution method implemented into a Millipore Glass Microanalysis system was used for recovery of Cryptosporidium parvum oocysts seeded into 25 l of drinking water in polyethylene carboy aspirator bottles. CAM-entrapped oocysts were detected by immunofluorescence microscopy. From 65 to 94 oocysts/l (mean 75 oocysts/l), 34.7% overall of the inoculated oocysts, were unrecovered as determined after the water had been drained from the bottle, rinsed with 1 l of eluting fluid (EF), and CAM-filtered. Efficiency rates of oocyst recovery ranged from 24.0% to 64.0% (mean 44.1%), without the use of EF and from 72.1% to 82.3% (mean 78.8%) when EF was used. To ensure a high recovery efficiency of Cryptosporidium oocysts from sampled water by the CAM-filter dissolution method, it is recommended that 1 l of EF per 25 l of water be used. PMID:9039693

  1. The influence of amorphization methods on the apparent solubility and dissolution rate of tadalafil.

    PubMed

    Wlodarski, K; Sawicki, W; Paluch, K J; Tajber, L; Grembecka, M; Hawelek, L; Wojnarowska, Z; Grzybowska, K; Talik, E; Paluch, M

    2014-10-01

    This study for the first time investigates the solubility and dissolution rate of amorphous tadalafil (Td)--a poorly water soluble chemical compound which is commonly used for treating the erectile dysfunction. To convert the crystalline form of Td drug to its amorphous counterpart we have employed most of the commercially available amorphization techniques i.e. vitrification, cryogenic grinding, ball milling, spray drying, freeze drying and antisolvent precipitation. Among the mentioned methods only quenched cooling of the molten sample was found to be an inappropriate method of Td amorphization. This is due to the thermal decomposition of Td above 200°C, as proved by the thermogravimetric analysis (TGA). Disordered character of all examined samples was confirmed using differential scanning calorimetry (DSC) and X-ray powder diffraction (PXRD). In the case of most amorphous powders, the largest 3-fold increase of apparent solubility was observed after 5 min, indicating their fast recrystallization in water. On the other hand, the partially amorphous precipitate of Td and hypromellose enhanced the solubility of Td approximately 14 times, as compared with a crystalline substance, which remained constant for half an hour. Finally, disk intrinsic dissolution rate (DIDR) of amorphous forms of Td was also examined. PMID:24907679

  2. Development of a bio-relevant dissolution test device simulating mechanical aspects present in the fed stomach.

    PubMed

    Koziolek, Mirko; Görke, Kristin; Neumann, Marco; Garbacz, Grzegorz; Weitschies, Werner

    2014-06-16

    A novel bio-relevant in vitro dissolution device was designed to mimic intragastric conditions after food intake paying particular consideration to mechanical aspects: the Fed Stomach Model (FSM). The FSM represents a fully computer-controlled dynamic flow-through system, in which dosage forms are hosted in so-called gastric vessels. Dosage form movement profiles as well as pressures can be simulated in a physiologically relevant manner. This proof-of-concept study aimed at the investigation of the effects of individual parameters and complex test programs on the drug delivery behavior of diclofenac sodium bilayer extended release tablets. Magnetic marker monitoring experiments demonstrated the applicability of the FSM to simulate intragastric movement velocities of solid oral dosage forms equivalent to in vivo data. Dissolution experiments revealed the relevance of all simulated parameters (i.e. pressure, dosage form movement and pump rate). Moreover, three different test scenarios with test programs specific for fundus, antrum and gastric emptying considered the variability of intragastric transit of solid oral dosage forms after food intake and were confirmed to be reasonable. Dissolution rates were low under conditions specific for fundus owing to low shear stresses. In contrast, higher amounts of the drug were released under high stress conditions simulating antral transit and gastric emptying. Concluding, the FSM can be a valuable tool for bio-relevant dissolution testing due to its potential of precise and reproducible simulation of mechanical parameters characteristic for the fed stomach.

  3. Comparison of methods for predicting dissolution and the theoretical implications of particle-size-dependent solubility.

    PubMed

    Johnson, Kevin C

    2012-02-01

    Experimental dissolution data of cilostazol suspensions and hydrocortisone powders were simulated using either the Wang-Flanagan equation (1999. J Pharm Sci 88:731-738; 2002. J Pharm Sci 91:534-542) or the method of Johnson and coworkers (1989. Int J Pharm 51:9-17; 1993. Pharm Res 10:1308-1314; 1996. Pharm Res 13:1795-1798; 2003. Drug Dev Ind Pharm 29:833-842). Both methods were able to simulate experimental data with similar accuracy. For the method of Johnson and coworkers (1989. Int J Pharm 51:9-17; 1993. Pharm Res 10:1308-1314; 1996. Pharm Res 13:1795-1798; 2003. Drug Dev Ind Pharm 29:833-842), a single set of hydrodynamic assumptions was able to simulate both cilostazol and hydrocortisone with similar accuracy. For the Wang-Flanagan equation (1999. J Pharm Sci 88:731-738; 2002. J Pharm Sci 91:534-542), significantly different diffusion layer thicknesses gave the best simulations for cilostazol and hydrocortisone, but a single value of 38 µm provided good overall simulation of dissolution. The general computational method was enhanced to make solubility dependent on particle size, according to the Ostwald-Freundlich equation; it was also able to simulate Ostwald ripening. The enhanced computational method provided no way to explain the large increase in bioavailability of cilostazol in dogs when the drug was dosed as a nanoparticle versus micronized preparation. The method provides a computational tool for exploring theoretical implications and explaining the behavior of nanoparticles.

  4. Mechanical clot dissolution: new concept.

    PubMed

    Bildsoe, M C; Moradian, G P; Hunter, D W; Castaneda-Zuniga, W R; Amplatz, K

    1989-04-01

    The authors present preliminary data on in vitro mechanical clot dissolution by means of a catheter with a tiny high-speed propeller enclosed in a special housing. Preweighed human blood clots were subjected to the catheter in a test tube with saline at various propeller speeds and durations of application. After filtration of the resultant slurry, the clot residue was weighed and examined histologically. Clot dissolution was found to be related to both the duration and speed of propeller rotation. No fibrin residue was seen after dissolution, although potential embolic material, composed of clumps of cellular debris as large as 208 microns in longest dimension, was found. Mechanical clot dissolution could possibly be used in any natural or synthetic blood vessel in which there is acute or subacute thrombosis, with fewer complications and lower cost than obtained with traditional methods.

  5. Fluid dynamics test method

    NASA Technical Reports Server (NTRS)

    Gayman, W. H.

    1974-01-01

    Test method and apparatus determine fluid effective mass and damping in frequency range where effective mass may be considered as total mass less sum of slosh masses. Apparatus is designed so test tank and its mounting yoke are supported from structural test wall by series of flexures.

  6. In Vitro Dissolution Tests of Plutonium and Americium Containing Contamination Originating From ZPPR Fuel Plates

    SciTech Connect

    William F. Bauer; Brian K. Schuetz; Gary M. Huestis; Thomas B. Lints; Brian K. Harris; R. Duane Ball; Gracy Elias

    2012-09-01

    Assessing the extent of internal dose is of concern whenever workers are exposed to airborne radionuclides or other contaminants. Internal dose determinations depend upon a reasonable estimate of the expected biological half-life of the contaminants in the respiratory tract. One issue with refractory elements is determining the dissolution rate of the element. Actinides such as plutonium (Pu) and Americium (Am) tend to be very refractory and can have biological half-lives of tens of years. In the event of an exposure, the dissolution rates of the radionuclides of interest needs to be assessed in order to assign the proper internal dose estimates. During the November 2011 incident at the Idaho National Laboratory (INL) involving a ZPPR fuel plate, air filters in a constant air monitor (CAM) and a giraffe filter apparatus captured airborne particulate matter. These filters were used in dissolution rate experiments to determine the apparent dissolution half-life of Pu and Am in simulated biological fluids. This report describes these experiments and the results. The dissolution rates were found to follow a three term exponential decay equation. Differences were noted depending upon the nature of the biological fluid simulant. Overall, greater than 95% of the Pu and 93% of the Am were in a very slow dissolving component with dissolution half-lives of over 10 years.

  7. Modern Methods of Testing

    NASA Technical Reports Server (NTRS)

    Seeber, F

    1939-01-01

    After a brief survey of the commonly used single-value test methods, the importance of the determination of the incipient knock for the octane number is discussed and improvements suggested for the knock testing in the CFR engine. The DVL supercharge test method with its superiority of direct determination of fuel knock in each single cylinder of an airplane engine without involving structural changes, is described and the advantages of a multiple-value method enumerated. A diagrammatic presentation of the knock characteristics is presented.

  8. Ignitability test method. II

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.; Schimmel, Morry L.

    1990-01-01

    To determine functional performance of initiating devices, the NASA's Langley Research Center's novel ignitability research on percussion primers has been expanded in 1989 to include measurements of function time, the evaluation of six primer lots (five types), and the determination of the effects of the military cold-temperature requirement of -65 F and primer output closure disks. This test method, a major improvement over the prior primer output test methods, fully met all objectives, while showing a significant amount of ignition variability.

  9. LEAKAGE TESTING METHOD

    DOEpatents

    McAdams, Wm.A.; Foss, M.H.

    1958-08-12

    A method of testing containers for leaks is described, particularly the testing of containers or cans in which the uranium slugs for nuelear reactors are jacketed. This method involves the immersion of the can in water under l50 pounds of pressure, then removing, drying, and coating the can with anhydrous copper sulfate. Amy water absorbed by the can under pressure will exude and discolor the copper sulfate in the area about the leak.

  10. [In vitro dissolution rate of Liuwei Wuling tablet based on biological potency and integrated dissolution].

    PubMed

    Zheng, Juan; Cheng, Ling; Shen, Cheng-ying; Li, Juan-juan; Qiu, Ling; Shen, Gang; Han, Jin; Yuan, Hai-long

    2015-11-01

    To explore the feasibility of chemical and biological method in evaluation of the in vitro dissolution rate of Liuwei Wuling tablet (LWT), this experiment investigated the inhibitory effect of LWT dissolving solutions on LX-2 hepatic stellate cells in 0.1% SDS dissolution medium in different dissolving periods. From these results, the cumulative dissolution rate of LWT was obtained based on the cell inhibitory rate. The dissolution rates of deoxyschizandrin, phillyrin, and Specnuezhenide were determined by HPLC method. A novel approach of self-defined weighting coefficient had been created to establish the integrated dissolution rate model. Then f2 similar factor method was used to evaluate the relevance of these two methods. The results showed that f2 values for deoxyschizandrin, phillyrin, Specnuezhenide, and the integrated dissolution were 61, 43, 61 and 75 respectively, indicating that the dissolution of multi-component integration could fully reflect the biological potency of the whole recipe. The dissolution evaluation method for multicomponent integration based on biological activity is expected to be one of the effective means for in vitro dissolution test of LWT. PMID:27097413

  11. Ignitability test method

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.; Schimmel, Morry L.

    1989-01-01

    To overcome serious weaknesses in determining the performance of initiating devices, a novel 'ignitability test method', representing actual design interfaces and ignition materials, has been developed. Ignition device output consists of heat, light, gas an burning particles. Past research methods have evaluated these parameters individually. This paper describes the development and demonstration of an ignitability test method combining all these parameters, and the quantitative assessment of the ignition performance of two widely used percussion primers, the M42C1-PA101 and the M42C2-793. The ignition materials used for this evaluation were several powder, granule and pellet sizes of black powder and boron-potassium nitrate. This test method should be useful for performance evaluation of all initiator types, quality assurance, evaluation of ignition interfaces, and service life studies of initiators and ignition materials.

  12. Standard environmental test methods

    SciTech Connect

    Schafer, D R

    1983-12-01

    This guide to uniformity in testing is intended primarily as an aid to persons responsible for designing, developing, and performing environmental tests. It will also be of use to those concerned with production, evaluation, and quality control and assurance. Checklists for preparing the environmental testing portion of product specifications are included, as are copies of Process Standards covering the instrumentation, equipment, and methods for use in environmental testing of Sandia National Laboratories components. Techniques and equipment are constantly improving. This version of SC-4452 reflects current state-of-the-art and practice in environmental testing. Previously existing sections of the document have ben updated and new ones have been added, e.g., Transient Testing on Vibration Machines.

  13. Using a Word Association Test for the Assessment of High School Students' Cognitive Structures on Dissolution

    ERIC Educational Resources Information Center

    Derman, Aysegul; Eilks, Ingo

    2016-01-01

    Understanding students' cognitive structures in a specific knowledge domain helps to determine the ''what, how and why'' features of such knowledge, so that we can take these structures into consideration in teaching. The purpose of the present study was to identify students' cognitive structures about solution and dissolution concepts. The study…

  14. [Dissolution study of the gentin tablets].

    PubMed

    Tsagareishvili, N T; Bakuridze, A D; Kurdiani, N G; Murtazashvili, T Zh

    2006-04-01

    To establish individual dissolution test for the tablets gentin, which have a marked influence on the secretory function of the stomach (increase the free acidity of the gastric juice and stimulate enzymoproduction function of the stomach), and gastroprotective functioning, the conditions for the test realization were studied and specified, using apparatus "Rotating Basket" (Dissolution test, apparatus 1, p.1791, USP XXIII, 1995). For the quantification of the active ingredients in buffer solutions chromatospectrophotometric method was used. The same conditions were used for the accomplishment of the dissolution test using apparatus "Rotating Paddle" (Dissolution test, apparatus 2, p.1791, USP XXIII, 1995). Metrologic characteristics were compared for the evaluation of the reproducibility of the results. Obtained data showed better reproducibility of the results for the apparatus "Rotating Paddle" compare to the apparatus "Rotating Basket". Estimated conditions are useful for the routine control of the tablets "Gentin" in the case of manufacturing.

  15. Bubble size distribution in acoustic droplet vaporization via dissolution using an ultrasound wide-beam method.

    PubMed

    Xu, Shanshan; Zong, Yujin; Li, Wusong; Zhang, Siyuan; Wan, Mingxi

    2014-05-01

    Performance and efficiency of numerous cavitation enhanced applications in a wide range of areas depend on the cavitation bubble size distribution. Therefore, cavitation bubble size estimation would be beneficial for biological and industrial applications that rely on cavitation. In this study, an acoustic method using a wide beam with low pressure is proposed to acquire the time intensity curve of the dissolution process for the cavitation bubble population and then determine the bubble size distribution. Dissolution of the cavitation bubbles in saline and in phase-shift nanodroplet emulsion diluted with undegassed or degassed saline was obtained to quantify the effects of pulse duration (PD) and acoustic power (AP) or peak negative pressure (PNP) of focused ultrasound on the size distribution of induced cavitation bubbles. It was found that an increase of PD will induce large bubbles while AP had only a little effect on the mean bubble size in saline. It was also recognized that longer PD and higher PNP increases the proportions of large and small bubbles, respectively, in suspensions of phase-shift nanodroplet emulsions. Moreover, degassing of the suspension tended to bring about smaller mean bubble size than the undegassed suspension. In addition, condensation of cavitation bubble produced in diluted suspension of phase-shift nanodroplet emulsion was involved in the calculation to discuss the effect of bubble condensation in the bubble size estimation in acoustic droplet vaporization. It was shown that calculation without considering the condensation might underestimate the mean bubble size and the calculation with considering the condensation might have more influence over the size distribution of small bubbles, but less effect on that of large bubbles. Without or with considering bubble condensation, the accessible minimum bubble radius was 0.4 or 1.7 μm and the step size was 0.3 μm. This acoustic technique provides an approach to estimate the size

  16. Development and application of a validated HPLC method for the analysis of dissolution samples of levothyroxine sodium drug products.

    PubMed

    Collier, J W; Shah, R B; Bryant, A R; Habib, M J; Khan, M A; Faustino, P J

    2011-02-20

    A rapid, selective, and sensitive gradient HPLC method was developed for the analysis of dissolution samples of levothyroxine sodium tablets. Current USP methodology for levothyroxine (L-T(4)) was not adequate to resolve co-elutants from a variety of levothyroxine drug product formulations. The USP method for analyzing dissolution samples of the drug product has shown significant intra- and inter-day variability. The sources of method variability include chromatographic interferences introduced by the dissolution media and the formulation excipients. In the present work, chromatographic separation of levothyroxine was achieved on an Agilent 1100 Series HPLC with a Waters Nova-pak column (250 mm × 3.9 mm) using a 0.01 M phosphate buffer (pH 3.0)-methanol (55:45, v/v) in a gradient elution mobile phase at a flow rate of 1.0 mL/min and detection UV wavelength of 225 nm. The injection volume was 800 μL and the column temperature was maintained at 28°C. The method was validated according to USP Category I requirements. The validation characteristics included accuracy, precision, specificity, linearity, and analytical range. The standard curve was found to have a linear relationship (r(2)>0.99) over the analytical range of 0.08-0.8 μg/mL. Accuracy ranged from 90 to 110% for low quality control (QC) standards and 95 to 105% for medium and high QC standards. Precision was <2% at all QC levels. The method was found to be accurate, precise, selective, and linear for L-T(4) over the analytical range. The HPLC method was successfully applied to the analysis of dissolution samples of marketed levothyroxine sodium tablets.

  17. Validation and application of a new reversed phase HPLC method for in vitro dissolution studies of rabeprazole sodium in delayed-release tablets.

    PubMed

    Nawaz, Md Saddam

    2013-01-01

    The purpose of this study was to develop and validate a new reversed phase high performance liquid chromatographic (RP-HPLC) method to quantify in vitro dissolution assay of rabeprazole sodium in pharmaceutical tablet dosage form. Method development was performed on C 18, 100 × 4.6 mm ID, and 10  μ m particle size column, and injection volume was 20  μ L using a diode array detector (DAD) to monitor the detection at 280 nm. The mobile phase consisted of buffer: acetonitrile at a ratio of 60 : 40 (v/v), and the flow rate was maintained at 1.0 mL/min. The method was validated in terms of suitability, linearity, specificity, accuracy, precision, stability, and sensitivity. Linearity was observed over the range of concentration 0.05-12.0  μ g/mL, and the correlation coefficient was found excellent >0.999. The method was specific with respect to rabeprazole sodium, and the peak purity was found 99.99%. The method was precise and had relative standard deviations (RSD) less than 2%. Accuracy was found in the range of 99.9 to 101.9%. The method was robust in different variable conditions and reproducible. This proposed fast, reliable, cost-effective method can be used as quality control tool for the estimation of rabeprazole sodium in routine dissolution test analysis. PMID:24062966

  18. A silica-supported solid dispersion of bifendate using supercritical carbon dioxide method with enhanced dissolution rate and oral bioavailability.

    PubMed

    Cai, Cuifang; Liu, Muhua; Li, Yun; Guo, Bei; Chang, Hui; Zhang, Xiangrong; Yang, Xiaoxu; Zhang, Tianhong

    2016-01-01

    In this study, to enhance the dissolution rate and oral bioavailability of bifendate, a silica-supported solid dispersion (SD) of bifendate was prepared using supercritical carbon dioxide (ScCO2) technology. The properties of bifendate-silica SD were characterized by differential scanning calorimetry (DSC), X-ray diffraction (X-RD) and scanning electron microscopy. The pharmacokinetic study was carried out in beagle dogs using commercial bifendate dropping pills as a reference which is a conventional SD formulation of bifendate and PEG6000. A novel method of Ultra Performance Convergence Chromatography-tandem mass spectrometry (UPC(2)™-MS/MS) method was applied to determine bifendate concentration in plasma. The amorphous state of bifendate in bifendate-silica SD was revealed in X-RD and DSC when the ratios of bifendate and silica were 1:15 and 1:19, respectively. In vitro dissolution rate was significantly improved with cumulative release of 67% within 20 min relative to 8% for the physical mixture of bifendate and silica, and which was also higher than the commercial dropping pill of 52%. After storage at 75% relative humidity (RH) for 10 d, no recrystallization was found and reduced dissolution rate was obtained due to the absorption of moisture. In pharmacokinetic study, Cmax and AUC0-t for bifendate-silica SD were 153.1 ng/ml and 979.8 ng h/ml, respectively. AUC0-t of bifendate-silica SDs was ∼1.6-fold higher than that of the commercial dropping pills. These results suggest that adsorbing bifendate onto porous silica via ScCO2 technique could be a feasible method to enhance oral bioavailability together with a higher dissolution rate.

  19. Selection of a discriminant and biorelevant in vitro dissolution test for the development of fenofibrate self-emulsifying lipid-based formulations.

    PubMed

    Pestieau, Aude; Krier, Fabrice; Brouwers, Adeline; Streel, Bruno; Evrard, Brigitte

    2016-09-20

    Fenofibrate, a BCS class II compound, has a low bioavailability especially when taken orally on an empty stomach. The challenge to find a new formulation for providing bioavailability, independent of food, is still ongoing. If the development of a suitable oral delivery formulation of BCS class II compounds is a frequent and great challenge to formulation scientists, the in vitro evaluation of these new formulations is also a great challenge. The purpose of this study was therefore to select an in vitro dissolution test that would be useful and as biorelevant as possible for the development of fenofibrate self-emulsifying lipid-based formulations. In this context, three different fenofibrate formulations, for which in vivo data are available in the literature, were tested using different dissolution tests until we found the one that was the most suitable. As part of this approach, we started with the simplest in vitro dissolution tests and progressed to tests that were increasingly more complex. The first tests were different single phase dissolution tests: a test under sink conditions based on the USP monograph, and different tests under non-sink conditions in non-biorelevant and biorelevant media. Given the inconclusive results obtained with these tests, biphasic dissolution systems were then tested: one with USP apparatus type II alone and another which combined USP apparatus types II and IV. This last combined test seemed the most suitable in vitro dissolution test for the development of the future fenofibrate lipid-based formulations we intend to develop in our own laboratory. PMID:27169683

  20. Selection of a discriminant and biorelevant in vitro dissolution test for the development of fenofibrate self-emulsifying lipid-based formulations.

    PubMed

    Pestieau, Aude; Krier, Fabrice; Brouwers, Adeline; Streel, Bruno; Evrard, Brigitte

    2016-09-20

    Fenofibrate, a BCS class II compound, has a low bioavailability especially when taken orally on an empty stomach. The challenge to find a new formulation for providing bioavailability, independent of food, is still ongoing. If the development of a suitable oral delivery formulation of BCS class II compounds is a frequent and great challenge to formulation scientists, the in vitro evaluation of these new formulations is also a great challenge. The purpose of this study was therefore to select an in vitro dissolution test that would be useful and as biorelevant as possible for the development of fenofibrate self-emulsifying lipid-based formulations. In this context, three different fenofibrate formulations, for which in vivo data are available in the literature, were tested using different dissolution tests until we found the one that was the most suitable. As part of this approach, we started with the simplest in vitro dissolution tests and progressed to tests that were increasingly more complex. The first tests were different single phase dissolution tests: a test under sink conditions based on the USP monograph, and different tests under non-sink conditions in non-biorelevant and biorelevant media. Given the inconclusive results obtained with these tests, biphasic dissolution systems were then tested: one with USP apparatus type II alone and another which combined USP apparatus types II and IV. This last combined test seemed the most suitable in vitro dissolution test for the development of the future fenofibrate lipid-based formulations we intend to develop in our own laboratory.

  1. Studies on the dissolution of polycyclic aromatic hydrocarbons from contaminated materials using a novel dialysis tubing experimental method

    SciTech Connect

    Woolgar, P.J. Scottish Environment Protection Agency, Stirling ); Jones, K.C. )

    1999-06-15

    Assessment of risk and remediation strategies at contaminated sites requires that both the amounts of contaminants present and their potential for release from materials and soils be evaluated. The release, or dissolution, of polycyclic aromatic hydrocarbons (PAHs) from contaminated materials to water was therefore investigated. To facilitate investigations of PAH dissolution from physically disparate materials such as solid coal tars, creosote, oil, and spent oxide, an experimental method for measuring dissolved PAHs was developed employing dialysis tubing in batch-type system. This was validated and compared to aqueous-phase PAH concentrations measured using more traditional techniques and also predicted using Raoult's law. The experimental procedure was successfully used to determine near equilibrium aqueous concentrations of PAHs, but it could only be used to determine relative rates of approach to equilibrium as the dialysis tubing effected the rate constants. It was found that the contaminant materials influenced dissolution, in particular the close to equilibrium concentrations. For materials chemically similar to PAHs, such as nonaqueous-phase liquids (NAPLs), the concentrations could be predicted using Raoult's law. For materials that were chemically dissimilar to PAHs, such as spent oxide, release was more thermodynamically favorable than for NAPLs.

  2. Development and validation of a method for simultaneous estimation of ofloxacin and ornidazole in different dissolution media

    PubMed Central

    Patel, Dasharath M.; Soneji, Jignesh A.; Patel, Parth B.; Patel, Chhagan N.

    2012-01-01

    Introduction: Ofloxacin and ornidazole in a combined tablet dosage form is available in the market. This combination has gained increasing acceptance in diarrhea caused due to bacterial and protozoal infections. Ofloxacin and ornidazole are also combined in the capsule dosage form to modify its release pattern in different studies. Spectrophotometric and HPTLC methods have been reported for their simultaneous estimation in the tablet dosage form in specific solvents. This paper presents a simple, accurate, and reproducible spectrophotometric method for simultaneous estimation of ofloxacin and ornidazole in the tablet dosage form in different dissolution media. The reported method is helpful in determination of ofloxacin and ornidazole during a dissolution study. Materials and Methods: A simple, sensitive, accurate, and economical spectrophotometric method based on the simultaneous equation was developed for the estimation of ornidazole and ofloxacin simultaneously in the tablet or capsule dosage form in different dissolution media at different pH values. Results: Ofloxacin showed absorption maxima at 294 nm in 0.1 N HCl and at 287 nm in phosphate buffer pH 6.8 and phosphate buffer pH 7.4 while ornidazole showed absorption maxima at 277 nm in 0.1 N HCl and at 319 nm in two buffers, respectively. The linearity was obtained in the concentration range of 1–8 μg/ ml for ofloxacin and 4–26 μg/ml for ornidazole. Discussion: The concentrations of the drugs were determined by the simultaneous equation method. The results of analysis have been validated statistically and by recovery studies. PMID:23781488

  3. Fabrication of fenofibrate nanocrystals by probe sonication method for enhancement of dissolution rate and oral bioavailability.

    PubMed

    Ige, Pradum Pundlikrao; Baria, Rohan K; Gattani, Surendra G

    2013-08-01

    Fenofibrate (FBT) is lipophillic drug used in hypercholesterolemia and hypertriglyceridemia having logP 5.375, low solubility (practically insoluble in water) and low oral bioavailability (36%). The purpose of work was to develop FBT nanocrystals for the enhancement of solubility and oral bioavailability. Fenofibrate nanosuspension was prepared using probe sonicator and transformed into dry powder using freeze drying and characterized by DSC, FTIR, XRPD, SEM, particle size, polydispersity index (PDI), zeta potential, solubility, in vitro dissolution, in vivo bioavailability and stability studies. Formulation FNS3 and pure drug exhibited the in vitro dissolution about 73.89% and 8.53% in 1% sodium lauryl sulfate (SLS) media, respectively. When the particle size reduced from 80,000±923nm to 460±20nm, saturation solubility was significantly increased. The saturation solubility of formulation FNS3 in 0.5% and 1% of SLS media found to be 67.51±1.5μg/mL and 107±1.9μg/mL, respectively. While, the saturation solubility of pure drug in 0.5% and 1% of SLS was found to be 6.02±1.51μg/ml and 23.54±1.54μg/ml, respectively. The pharmacokinetic study of optimized nanocrystals (FNS3) conducted in New Zealand white rabbits showed 4.73-fold increase in relative bioavailability than that of pure drug. Long term stability studies showed that there was no significant change in the mean particle size and PDI at 5°C±3°C after 180 days. This enhanced dissolution and bioavailability of fenofibrate nanocrystals could be the promising approach for oral delivery.

  4. Dissolution-precipitation processes in tank experiments for testing numerical models for reactive transport calculations: Experiments and modelling

    NASA Astrophysics Data System (ADS)

    Poonoosamy, Jenna; Kosakowski, Georg; Van Loon, Luc R.; Mäder, Urs

    2015-06-01

    In the context of testing reactive transport codes and their underlying conceptual models, a simple 2D reactive transport experiment was developed. The aim was to use simple chemistry and design a reproducible and fast to conduct experiment, which is flexible enough to include several process couplings: advective-diffusive transport of solutes, effect of liquid phase density on advective transport, and kinetically controlled dissolution/precipitation reactions causing porosity changes. A small tank was filled with a reactive layer of strontium sulfate (SrSO4) of two different grain sizes, sandwiched between two layers of essentially non-reacting quartz sand (SiO2). A highly concentrated solution of barium chloride was injected to create an asymmetric flow field. Once the barium chloride reached the reactive layer, it forced the transformation of strontium sulfate into barium sulfate (BaSO4). Due to the higher molar volume of barium sulfate, its precipitation caused a decrease of porosity and lowered the permeability. Changes in the flow field were observed with help of dye tracer tests. The experiments were modelled using the reactive transport code OpenGeosys-GEM. Tests with non-reactive tracers performed prior to barium chloride injection, as well as the density-driven flow (due to the high concentration of barium chloride solution), could be well reproduced by the numerical model. To reproduce the mineral bulk transformation with time, two populations of strontium sulfate grains with different kinetic rates of dissolution were applied. However, a default porosity permeability relationship was unable to account for measured pressure changes. Post mortem analysis of the strontium sulfate reactive medium provided useful information on the chemical and structural changes occurring at the pore scale at the interface that were considered in our model to reproduce the pressure evolution with time.

  5. Dissolution-precipitation processes in tank experiments for testing numerical models for reactive transport calculations: Experiments and modelling.

    PubMed

    Poonoosamy, Jenna; Kosakowski, Georg; Van Loon, Luc R; Mäder, Urs

    2015-01-01

    In the context of testing reactive transport codes and their underlying conceptual models, a simple 2D reactive transport experiment was developed. The aim was to use simple chemistry and design a reproducible and fast to conduct experiment, which is flexible enough to include several process couplings: advective-diffusive transport of solutes, effect of liquid phase density on advective transport, and kinetically controlled dissolution/precipitation reactions causing porosity changes. A small tank was filled with a reactive layer of strontium sulfate (SrSO4) of two different grain sizes, sandwiched between two layers of essentially non-reacting quartz sand (SiO2). A highly concentrated solution of barium chloride was injected to create an asymmetric flow field. Once the barium chloride reached the reactive layer, it forced the transformation of strontium sulfate into barium sulfate (BaSO4). Due to the higher molar volume of barium sulfate, its precipitation caused a decrease of porosity and lowered the permeability. Changes in the flow field were observed with help of dye tracer tests. The experiments were modelled using the reactive transport code OpenGeosys-GEM. Tests with non-reactive tracers performed prior to barium chloride injection, as well as the density-driven flow (due to the high concentration of barium chloride solution), could be well reproduced by the numerical model. To reproduce the mineral bulk transformation with time, two populations of strontium sulfate grains with different kinetic rates of dissolution were applied. However, a default porosity permeability relationship was unable to account for measured pressure changes. Post mortem analysis of the strontium sulfate reactive medium provided useful information on the chemical and structural changes occurring at the pore scale at the interface that were considered in our model to reproduce the pressure evolution with time.

  6. Dissolution rate of borosilicate glass SON68: A method of quantification based upon interferometry and implications for experimental and natural weathering rates of glass

    NASA Astrophysics Data System (ADS)

    Icenhower, Jonathan P.; Steefel, Carl I.

    2015-05-01

    Rates of glass dissolution from laboratory and field studies are often considered to be irreconcilable, although potential causes for the difference, such as solution saturation state and increasing surface area from progressive weathering, have not been explored in depth. The dissolution rate of SON68 glass, the non-radioactive analog of the French R7T7 composition, was determined in a single-pass flow-through (SPFT) system at 90 °C and pH 9 over a silica-saturation interval. Dissolution rates were determined on both powdered and monolithic specimens by assaying the concentration of elements released from glass to effluent solution. In addition, rates of 12 monolithic specimens were quantified using a Vertical Scanning Interferometry (VSI) method. The method entails measuring the difference in height between a reference and reaction surface. The height difference is proportional to the dissolution rate. By adjusting the relative position of the reacted surface to average surface roughness, the effects of surface area on the dissolution rate can be minimized. Values of the dissolution rate, based upon chemical assay of the effluent solution on the one hand, and VSI methods on the other, were compared. In general, rates determined by the two methods are within a factor of 2×. The difference in rates may be due to the presence of a reaction layer that develops on the glass surface, resulting in an underestimation of the height difference measurement. The dissolution rates of SON68 glass in silica-saturated solutions were then compared to rates previously determined on basalt glass in natural weathering environments (Gordon and Brady, 2002, Chem. Geol. 190, 113-122). When adjusted for differences in temperature and pH, the ranges of borosilicate and basalt glass dissolution rates overlap, indicating that laboratory and field rates can be reconciled and that the principal control on glass dissolution is solution saturation with respect to amorphous silica.

  7. Dissolution and Separation of Aluminum and Aluminosilicates

    SciTech Connect

    McFarlane, Joanna; Benker, Dennis; DePaoli, David W.; Felker, Leslie Kevin; Mattus, Catherine H.

    2015-12-19

    The selection of an aluminum alloy for target irradiation affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the dissolver, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. Aluminosilicate dissolution presents challenges in a number of different areas, metals extraction from minerals, flyash treatment, and separations from aluminum alloys. We present experimental work that attempts to maximize dissolution of aluminum metal, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as a function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. Our data have been compared with published calculations of aluminum phase diagrams. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.

  8. Dissolution and Separation of Aluminum and Aluminosilicates

    DOE PAGESBeta

    McFarlane, Joanna; Benker, Dennis; DePaoli, David W.; Felker, Leslie Kevin; Mattus, Catherine H.

    2015-12-19

    The selection of an aluminum alloy for target irradiation affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the dissolver, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. Aluminosilicate dissolution presents challenges in a number of different areas, metals extraction from minerals, flyash treatment, and separations from aluminum alloys. We present experimental work that attempts to maximize dissolution of aluminum metal, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as amore » function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. Our data have been compared with published calculations of aluminum phase diagrams. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.« less

  9. Intermediate Scale Laboratory Testing to Understand Mechanisms of Capillary and Dissolution Trapping during Injection and Post-Injection of CO2 in Heterogeneous Geological Formations

    SciTech Connect

    Illangasekare, Tissa; Trevisan, Luca; Agartan, Elif; Mori, Hiroko; Vargas-Johnson, Javier; Gonzalez-Nicolas, Ana; Cihan, Abdullah; Birkholzer, Jens; Zhou, Quanlin

    2015-03-31

    Carbon Capture and Storage (CCS) represents a technology aimed to reduce atmospheric loading of CO2 from power plants and heavy industries by injecting it into deep geological formations, such as saline aquifers. A number of trapping mechanisms contribute to effective and secure storage of the injected CO2 in supercritical fluid phase (scCO2) in the formation over the long term. The primary trapping mechanisms are structural, residual, dissolution and mineralization. Knowledge gaps exist on how the heterogeneity of the formation manifested at all scales from the pore to the site scales affects trapping and parameterization of contributing mechanisms in models. An experimental and modeling study was conducted to fill these knowledge gaps. Experimental investigation of fundamental processes and mechanisms in field settings is not possible as it is not feasible to fully characterize the geologic heterogeneity at all relevant scales and gathering data on migration, trapping and dissolution of scCO2. Laboratory experiments using scCO2 under ambient conditions are also not feasible as it is technically challenging and cost prohibitive to develop large, two- or three-dimensional test systems with controlled high pressures to keep the scCO2 as a liquid. Hence, an innovative approach that used surrogate fluids in place of scCO2 and formation brine in multi-scale, synthetic aquifers test systems ranging in scales from centimeter to meter scale developed used. New modeling algorithms were developed to capture the processes controlled by the formation heterogeneity, and they were tested using the data from the laboratory test systems. The results and findings are expected to contribute toward better conceptual models, future improvements to DOE numerical codes, more accurate assessment of storage capacities, and optimized placement strategies. This report presents the experimental and modeling methods

  10. Assessment of In Vivo Clinical Product Performance of a Weak Basic Drug by Integration of In Vitro Dissolution Tests and Physiologically Based Absorption Modeling.

    PubMed

    Ding, Xuan; Gueorguieva, Ivelina; Wesley, James A; Burns, Lee J; Coutant, Carrie A

    2015-11-01

    Effective integration of in vitro tests and absorption modeling can greatly improve our capability in understanding, comparing, and predicting in vivo performances of clinical drug products. In this case, we used a proprietary drug candidate galunisertib to describe the procedures of designing key in vitro tests, analyzing relevant experimental and trial data, and integrating them into physiologically based absorption models to evaluate the performances of its clinical products. By simulating the preclinical study result, we estimated high in vivo permeability for the drug. Given the high sensitivity of its solubility to pH, supersaturation may play an important role in the absorption of galunisertib. Using the dynamic dissolution test, i.e., artificial stomach-duodenum (ASD) model and simulation, we concluded galunisertib in solution or tablet products could maintain supersaturation during the transit in the gastrointestinal tract (GIT). A physiologically based absorption model was established by incorporating these key inputs in the simulation of Trial 1 results of galunisertib solution. To predict the performance of three tablet products, we developed z-factor dissolution models from the multi-pH USP dissolution results and integrate them into the absorption model. The resultant biopharmaceutical models provided good prediction of the extent of absorption of all three products, but underestimated the rate of absorption of one tablet product. Leveraging the ASD result and optimization with the dissolution model, we identified the limitation of the model due to complexity of estimating the dissolution parameter z and its in vitro-in vivo correlation.

  11. Accelerated Test Methods

    NASA Technical Reports Server (NTRS)

    Jansen, Ralph

    1995-01-01

    Neural network systems were evaluated for use in predicting wear of mechanical systems. Three different neural network software simulation packages were utilized in order to create models of tribological wear tests. Representative simple, medium, and high complexity simulation packages were selected. Pin-on-disk, rub shoe, and four-ball tribological test data was used for training, testing, and verification of the neural network models. Results showed mixed success. The neural networks were able to predict results with some accuracy if the number of input variables was low or the amount of training data was high. Increased neural network complexity resulted in more accurate results, however there was a point of diminishing return. Medium complexity models were the best trade off between accuracy and computing time requirements. A NASA Technical Memorandum and a Society of Tribologists and Lubrication Engineers paper are being published which detail the work.

  12. Physical and dissolution characterization of cilostazol solid dispersions prepared by hot melt granulation (HMG) and thermal adhesion granulation (TAG) methods.

    PubMed

    Chen, Ying-Chen; Ho, Hsiu-O; Chiou, Jiun-Da; Sheu, Ming-Thau

    2014-10-01

    A growing number of poorly water-soluble drug have been discovered, but the poor bioavailability is a critical problem. In this study, physical properties and dissolution profiles of cilostazol solid dispersions prepared by hydrophilic/lipophilic excipients (Kollidon(®) VA64, tocopheryl polyethylene glycol succinate (TPGS), vitamine E) with hot-melt and thermal adhesion granulation (TAG) method to adsorb Fujicalin(®) and Microcel(®) were characterized. Results demonstrate the angle of repose in formulations with Fujicalin(®) was improved than those with Microcel(®), but the difference disappeared when more TPGS or vitamin E was added. Compared the formulation made by hot-melt and TAG method, both improved flowability. The hardness decreased with the increased amount of TPGS and vitamin E. The formulations with Microcel(®) had lower hardness than those with Fujicalin(®), because Microcel(®) has weaker adsorption ability and cannot afford much TPGS and vitamin E, leading to lower hardness. Furthermore, the solubility was almost three-fold higher than that of Pletaal(®) (7.68 ± 0.20 μg/mL) in compositions containing TPGS and vitamin E made by hot-melt or TAG method, in which a controlled drug release pattern was demonstrated. There is no significant difference on dissolution profile between hot-melt and TAG method. However, the procedure of TAG is easier, indicating its potential pharmaceutical use. PMID:25089508

  13. Enhancement of the dissolution rate and bioavailability of fenofibrate by a melt-adsorption method using supercritical carbon dioxide

    PubMed Central

    Cha, Kwang-Ho; Cho, Kyung-Jin; Kim, Min-Soo; Kim, Jeong-Soo; Park, Hee Jun; Park, Junsung; Cho, Wonkyung; Park, Jeong-Sook; Hwang, Sung-Joo

    2012-01-01

    Background: The aim of this study was to enhance the bioavailability of fenofibrate, a poorly water-soluble drug, using a melt-adsorption method with supercritical CO2. Methods: Fenofibrate was loaded onto Neusilin® UFL2 at different weight ratios of fenofibrate to Neusilin UFL2 by melt-adsorption using supercritical CO2. For comparison, fenofibrate-loaded Neusilin UFL2 was prepared by solvent evaporation and hot melt-adsorption methods. The fenofibrate formulations prepared were characterized by differential scanning calorimetry, powder x-ray diffractometry, specific surface area, pore size distribution, scanning electron microscopy, and energy-dispersive x-ray spectrometry. In vitro dissolution and in vivo bioavailability were also investigated. Results: Fenofibrate was distributed into the pores of Neusilin UFL2 and showed reduced crystal formation following adsorption. Supercritical CO2 facilitated the introduction of fenofibrate into the pores of Neusilin UFL2. Compared with raw fenofibrate, fenofibrate from the prepared powders showed a significantly increased dissolution rate and better bioavailability. In particular, the area under the drug concentration-time curve and maximal serum concentration of the powders prepared using supercritical CO2 were 4.62-fold and 4.52-fold greater than the corresponding values for raw fenofibrate. Conclusion: The results of this study highlight the usefulness of the melt-adsorption method using supercritical CO2 for improving the bioavailability of fenofibrate. PMID:23118538

  14. [The in vitro dissolution of total composition of the tablet of rhizomes of Ligusticum chuanxiong components and in vitro-in vivo correlation by the method of area under the absorbance-wavelength curve].

    PubMed

    Lai, Hong-qiang; Hu, Yue; Li, Xiao-dong

    2015-06-01

    To discuss the availability of evaluation on the dissolution studies of the multicomponents in traditional Chinese medicine, the in vitro dissolution of total composition of the tablet of rhizomes of Ligusticum chuanxiong components and its correlation with the in vivo were studied by the method of area under the absorbance-wavelength curve (AUAWC). Taken the tablet of rhizomes of Ligusticum chuanxiong components which is composed of sodium ferulate and ligustrazine hydrochloride as subject model, the dissolution tests were carried out with basket method. The plasma concentrations of tablets in different rats were determined by AUAWC at different interval times. The in vivo absorption percentage was calculated by Wagner-Nelson equation to evaluate the in vitro and in vivo correlation. According to the results, the cumulative dissolution in vitro of total composition of tablets of rhizomes of Ligusticum chuanxiong components at 60 min was 90.65% in water by AUAWC. The in vivo pharmacokinetics is fitted with an one-compartment model. The linear equation based on the cumulative dissolution rate (fr) and absorption percentage (fa) at 5, 10, 20, 30 and 60 min was fa = 0.819 7 fr+0.183 and the correlation coefficient was 0.959 5, which showed a good correlation between the in vitro dissolution and the in vivo absorption percentage. The method of AUAWC can be used accurately, feasibly and conveniently to evaluate the in vitro and in vivo correlation of total composition of tablets of rhizomes of Ligusticum chuanxiong components, which will provide better guidance to study the in vitro and in vivo correlation of sustained release preparation etc under complex system of traditional Chinese medicine in the future. PMID:26521454

  15. METHOD FOR TESTING COATINGS

    DOEpatents

    Johns, I.B.; Newton, A.S.

    1958-09-01

    A method is described for detecting pin hole imperfections in coatings on uranium-metal objects. Such coated objects are contacted with a heated atmosphere of gaseous hydrogen and imperfections present in the coatings will allow the uranlum to react with the hydrogen to form uranium hydride. Since uranium hydride is less dense than uranium metal it will swell, causing enlargement of the coating defeot and rendering it visible.

  16. Comparative in vitro dissolution study of carbamazepine immediate-release products using the USP paddles method and the flow-through cell system

    PubMed Central

    Medina, José Raúl; Salazar, Dulce Karina; Hurtado, Marcela; Cortés, Alma Rosa; Domínguez-Ramírez, Adriana Miriam

    2013-01-01

    Dissolution profiles of four carbamazepine immediate-release generic products (200 mg tablets) and the reference product Tegretol® were evaluated using the USP paddles method and an alternative method with the flow-through cell system, USP Apparatus 4. Under official conditions all products met the Q specification, dissolution profiles of generic products were similar to the dissolution profile of the reference product (f2 > 50) and model-independent parameters showed non significant differences to the reference product except mean dissolution time for product A (p < 0.05). On the other hand, when the flow-through cell system was used, none of the products met the pharmacopeial specification at 15 min and product A did not reach dissolution criteria at 60 min, dissolution profiles of all generic products were not similar to the reference product profile (f2 < 50) and all model-independent parameters showed significant differences compared to the reference product (p < 0.05). Weibull’s model was more useful for adjusting the dissolution data of all products in both USP apparatuses and Td values showed significant differences compared to the reference product (p < 0.05) when USP Apparatus 4 was used. These results indicate that the proposed method, using the flow-through cell system, is more discriminative in evaluating both, rate and extent of carbamazepine dissolution process from immediate-release generic products. PMID:24648826

  17. Ultrasonic testing method

    SciTech Connect

    Ferreira, N.C.

    1989-02-21

    This patent describes an ultrasonic sound scanning method for detection of ultrasonic anomalies in a workpiece having an inspection surface and at least one formation which results in an echo-masked zone in the workpiece, the method including carrying out an inspection pass by (a) directing a beam of ultrasonic sound pulses from a probe along a beam axis through a transmission medium and impinging the beam upon the inspection surface at a selected impingement angle and thence into the workpiece, (b) receiving echo pulses thereby reflected from the workpiece, (c) displaying the echo pulses to reveal those, if any, which indicate the existence of anomalies within the workpiece, and (d) traversing the beam in a pre-selected path along the inspection surface, the improvement comprising: making one or more first inspection passes with the probe oriented so that, relative to the workpiece, the beam lies within one or more first scanning planes which are non-perpendicular to at least one of the return-reflecting formation at its point or respective points of intersection with the first plane or planes, whereby to reduce the volume of the echo-masked zone relative to that which would be generated with the probe oriented in a corresponding number or one or more scanning planes which are perpendicular to at least one return-reflecting formation.

  18. Predicting the oral pharmacokinetic profiles of multiple-unit (pellet) dosage forms using a modeling and simulation approach coupled with biorelevant dissolution testing: case example diclofenac sodium.

    PubMed

    Kambayashi, Atsushi; Blume, Henning; Dressman, Jennifer B

    2014-07-01

    The objective of this research was to characterize the dissolution profile of a poorly soluble drug, diclofenac, from a commercially available multiple-unit enteric coated dosage form, Diclo-Puren® capsules, and to develop a predictive model for its oral pharmacokinetic profile. The paddle method was used to obtain the dissolution profiles of this dosage form in biorelevant media, with the exposure to simulated gastric conditions being varied in order to simulate the gastric emptying behavior of pellets. A modified Noyes-Whitney theory was subsequently fitted to the dissolution data. A physiologically-based pharmacokinetic (PBPK) model for multiple-unit dosage forms was designed using STELLA® software and coupled with the biorelevant dissolution profiles in order to simulate the plasma concentration profiles of diclofenac from Diclo-Puren® capsule in both the fasted and fed state in humans. Gastric emptying kinetics relevant to multiple-units pellets were incorporated into the PBPK model by setting up a virtual patient population to account for physiological variations in emptying kinetics. Using in vitro biorelevant dissolution coupled with in silico PBPK modeling and simulation it was possible to predict the plasma profile of this multiple-unit formulation of diclofenac after oral administration in both the fasted and fed state. This approach might be useful to predict variability in the plasma profiles for other drugs housed in multiple-unit dosage forms.

  19. Setting dissolution specifications for modified-release dosage forms.

    PubMed

    Piscitelli, D A; Young, D

    1997-01-01

    Dissolution specifications are used for quality assurance and may also serve as a surrogate for in vivo bioavailability. These limits can guide formulation development and eliminate the need for bioavailability studies for scale up and post approval changes. Several methods for setting dissolution specifications have been reviewed in this chapter. A summary of the advantages and disadvantages for each method can be found in Table 1. When choosing a method for setting dissolution specifications, it is important to 1) have a discriminating dissolution system, 2) incorporate in vivo data, 3) include intersubject variability, and 4) predict plasma concentration-time profiles. Predicting plasma concentration curves allows one to see how the change in formulation or dissolution limits perform in vivo. Dissolution specifications should be set so that all formulations that have dissolution profiles within the limits of the specifications are bioequivalent. This can be assured if the boundaries are tested for bioequivalence. Minimally, the formulations that have dissolution profiles within the limits of the specifications should be bioequivalent to the pivotal batch. A population prediction of the plasma concentration-time profiles for the upper and lower limit would incorporate the true intersubject variability for the formulation. PMID:9269491

  20. Marital dissolution by sex of the petitioner: a test of the man-child affiliative bond.

    PubMed

    Mackey, W C

    1993-09-01

    The problems in disentangling the tabula rasa explanations, as opposed to the biocultural explanations, in the understanding and prediction of human behavior are deep, real, and difficult. This study tested two conflicting sets of predictions concerning divorce patterns in the United States: a socioeconomic set and a biocultural set. The socio-economic perspective predicts that the addition of one or more children to a marriage would increase the husband's (as compared with the wife's) motivation to petition for a divorce. The biocultural perspective posits that a man-to-child affiliative bond would add to a man's adherence to his child(ren) and, in turn, would lower his motivation (as compared with the woman's) to petition for a divorce. The biocultural perspective was supported in this study.

  1. Unidirectional Fabric Drape Testing Method

    PubMed Central

    Mei, Zaihuan; Yang, Jingzhi; Zhou, Ting; Zhou, Hua

    2015-01-01

    In most cases, fabrics such as curtains, skirts, suit pants and so on are draped under their own gravity parallel to fabric plane while the gravity is perpendicular to fabric plane in traditional drape testing method. As a result, it does not conform to actual situation and the test data is not convincing enough. To overcome this problem, this paper presents a novel method which simulates the real mechanical conditions and ensures the gravity is parallel to the fabric plane. This method applied a low-cost Kinect Sensor device to capture the 3-dimensional (3D) drape profile, thus we obtained the drape degree parameters and aesthetic parameters by 3D reconstruction and image processing and analysis techniques. The experiment was conducted on our self-devised drape-testing instrument by choosing different kinds of weave structure fabrics as our testing samples and the results were compared with those of traditional method and subjective evaluation. Through regression and correlation analysis we found that this novel testing method was significantly correlated with the traditional and subjective evaluation method. We achieved a new, non-contact 3D measurement method for drape testing, namely unidirectional fabric drape testing method. This method is more suitable for evaluating drape behavior because it is more in line with actual mechanical conditions of draped fabrics and has a well consistency with the requirements of visual and aesthetic style of fabrics. PMID:26600387

  2. Unidirectional Fabric Drape Testing Method.

    PubMed

    Mei, Zaihuan; Shen, Wei; Wang, Yan; Yang, Jingzhi; Zhou, Ting; Zhou, Hua

    2015-01-01

    In most cases, fabrics such as curtains, skirts, suit pants and so on are draped under their own gravity parallel to fabric plane while the gravity is perpendicular to fabric plane in traditional drape testing method. As a result, it does not conform to actual situation and the test data is not convincing enough. To overcome this problem, this paper presents a novel method which simulates the real mechanical conditions and ensures the gravity is parallel to the fabric plane. This method applied a low-cost Kinect Sensor device to capture the 3-dimensional (3D) drape profile, thus we obtained the drape degree parameters and aesthetic parameters by 3D reconstruction and image processing and analysis techniques. The experiment was conducted on our self-devised drape-testing instrument by choosing different kinds of weave structure fabrics as our testing samples and the results were compared with those of traditional method and subjective evaluation. Through regression and correlation analysis we found that this novel testing method was significantly correlated with the traditional and subjective evaluation method. We achieved a new, non-contact 3D measurement method for drape testing, namely unidirectional fabric drape testing method. This method is more suitable for evaluating drape behavior because it is more in line with actual mechanical conditions of draped fabrics and has a well consistency with the requirements of visual and aesthetic style of fabrics. PMID:26600387

  3. The difference between surface ocean carbonate chemistry and calcite dissolution in deep sea sediments as observed in tests of Globorotalia menardii

    NASA Astrophysics Data System (ADS)

    Russo, M.; Mekik, F.

    2010-12-01

    The Globorotalia menardii Fragmentation Index (MFI) was developed to trace deep sea calcite dissolution within sediments. While this proxy has a multi-basin core top calibration ranging the tropical and subtropical world ocean, the effect of the surface ocean [CO32-] on thickness of whole G. menardii shells has not been previously tested. If the size-normalized shell weight (SNSW) of G. menardii tests were affected by the [CO32-] of ambient habitat waters, this would put constraints on the applicability of MFI as a reliable bulk sediment calcite dissolution proxy. We present new SNSW data from G. menardii shells within core tops in the eastern equatorial Pacific where there is both a strong gradient to surface ocean [CO32-] and calcite dissolution in the sediments. We compare our G.menardii SNSW data with that of other species in the region, such as Neogloboquadrina dutertrei and Pulleniatina obliquiloculata. While SNSW of both N. dutertrei and P. obliquiloculata have clear relationships with surface ocean [CO32-], we do not find a similar relationship between G. menardii SNSW and surface ocean parameters, particularly [CO32-]. This bolsters our confidence in the reliability of MFI as a deep sea carbonate dissolution tracer.

  4. HEPA filter dissolution process

    DOEpatents

    Brewer, K.N.; Murphy, J.A.

    1994-02-22

    A process is described for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal. 4 figures.

  5. Hepa filter dissolution process

    DOEpatents

    Brewer, Ken N.; Murphy, James A.

    1994-01-01

    A process for dissolution of spent high efficiency particulate air (HEPA) filters and then combining the complexed filter solution with other radioactive wastes prior to calcining the mixed and blended waste feed. The process is an alternate to a prior method of acid leaching the spent filters which is an inefficient method of treating spent HEPA filters for disposal.

  6. Aluminum Target Dissolution in Support of the Pu-238 Program

    SciTech Connect

    McFarlane, Joanna; Benker, Dennis; DePaoli, David W; Felker, Leslie Kevin; Mattus, Catherine H

    2014-09-01

    Selection of an aluminum alloy for target cladding affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the caustic dissolution step, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. We present a study to maximize dissolution of aluminum metal alloy, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as a function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. These data have been compared with published calculations of aluminum phase diagrams. Temperature logging during the transients has been investigated as a means to generate kinetic and mass transport data on the dissolution process. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.

  7. [Test method for 6 phthalates in polyvinyl chloride].

    PubMed

    Abe, Yutaka; Mutsuga, Motoh; Hirahara, Yoshichika; Kawamura, Yoko

    2011-01-01

    A test method for 6 phthalates, bis(2-ethylhexyl)phthalate, dibutyl phthalate, benzyl butyl phthalate, diisononyl phthalate, diisodecyl phthalate and di-n-octyl phthalate, in polyvinyl chloride (PVC) was developed. GC/MS was used in the SIM mode for the separation and detection of phthalates. For preparation of the test solution, the extraction method with acetone-hexane mixture (3 : 7) and the dissolution method with tetrahydrofuran and ethanol were compared and it was confirmed that each method gave good recoveries. Dilution of the test solution was effective to reduce the influence of PVC. In a collaborative study with nine laboratories, the intra-laboratory variations showed good repeatability, but the measurements at some laboratories deviated widely. It appears that this method is unsuitable for the judgment of acceptability, but it may be suitable for the determination of phthalate content in PVC products.

  8. Coherent anti-Stokes Raman scattering (CARS) microscopy visualizes pharmaceutical tablets during dissolution.

    PubMed

    Fussell, Andrew L; Kleinebudde, Peter; Herek, Jennifer; Strachan, Clare J; Offerhaus, Herman L

    2014-01-01

    Traditional pharmaceutical dissolution tests determine the amount of drug dissolved over time by measuring drug content in the dissolution medium. This method provides little direct information about what is happening on the surface of the dissolving tablet. As the tablet surface composition and structure can change during dissolution, it is essential to monitor it during dissolution testing. In this work coherent anti-Stokes Raman scattering microscopy is used to image the surface of tablets during dissolution while UV absorption spectroscopy is simultaneously providing inline analysis of dissolved drug concentration for tablets containing a 50% mixture of theophylline anhydrate and ethyl cellulose. The measurements showed that in situ CARS microscopy is capable of imaging selectively theophylline in the presence of ethyl cellulose. Additionally, the theophylline anhydrate converted to theophylline monohydrate during dissolution, with needle-shaped crystals growing on the tablet surface during dissolution. The conversion of theophylline anhydrate to monohydrate, combined with reduced exposure of the drug to the flowing dissolution medium resulted in decreased dissolution rates. Our results show that in situ CARS microscopy combined with inline UV absorption spectroscopy is capable of monitoring pharmaceutical tablet dissolution and correlating surface changes with changes in dissolution rate. PMID:25045833

  9. Test methods for textile composites

    NASA Technical Reports Server (NTRS)

    Minguet, Pierre J.; Fedro, Mark J.; Gunther, Christian K.

    1994-01-01

    Various test methods commonly used for measuring properties of tape laminate composites were evaluated to determine their suitability for the testing of textile composites. Three different types of textile composites were utilized in this investigation: two-dimensional (2-D) triaxial braids, stitched uniweave fabric, and three-dimensional (3-D) interlock woven fabric. Four 2-D braid architectures, five stitched laminates, and six 3-D woven architectures were tested. All preforms used AS4 fibers and were resin-transfer-molded with Shell RSL-1895 epoxy resin. Ten categories of material properties were investigated: tension, open-hole tension, compression, open-hole compression, in-plane shear, filled-hole tension, bolt bearing, interlaminar tension, interlaminar shear, and interlaminar fracture toughness. Different test methods and specimen sizes were considered for each category of test. Strength and stiffness properties obtained with each of these methods are documented in this report for all the material systems mentioned above.

  10. Testing biodegradability with standardized methods.

    PubMed

    Pagga, U

    1997-12-01

    Laboratory test methods are used by industry laboratories to determine biodegradability, an important parameter for the evaluation of the ecological behaviour of substances. Biodegradability has a key role due to the simple fact that a degradable substance will cause no long term risk in the environment. The great variety of biodegradation processes in the natural environment and in technical plants for treating waste water and solid wastes gave rise to a rather large number of test methods based on different test principles. To guarantee the acceptance of the test results by authorities and customers internationally standardized methods (ISO, OECD) and established quality criteria (GLP, EN 45,000, ISO 9000) are used. PMID:9415981

  11. A Simplified Method for Measuring the Entropy Change of Urea Dissolution. An Experiment for the Introductory Chemistry Lab

    NASA Astrophysics Data System (ADS)

    Liberko, Charles A.; Terry, Stephanie

    2001-08-01

    The enthalpy change, equilibrium constant, Gibbs free energy change, and entropy change of the dissolution of urea in water were determined in a guided-inquiry lab experiment. Introductory-level students were able to obtain quite satisfactory thermodynamic values for the dissolution of urea using minimal equipment and a very simple procedure. The enthalpy change of dissolution was determined with a simple coffee-cup calorimeter. Students then directly determined the concentration of a saturated solution of urea simply by measuring the amount of urea used and the total volume of the solution as prepared in a graduated cylinder. The equilibrium expression for the dissolution of urea can be simplified to K = [urea]. With the enthalpy change and the equilibrium constant determined experimentally, the free energy change and enthalpy change for the process are readily calculated.

  12. SELECTIVE SEPARATION OF URANIUM FROM THORIUM, PROTACTINIUM AND FISSION PRODUCTS BY PEROXIDE DISSOLUTION METHOD

    DOEpatents

    Seaborg, G.T.; Gofman, J.W.; Stoughton, R.W.

    1959-08-18

    A method is described for separating U/sup 233/ from thorium and fission products. The separation is effected by forming a thorium-nitric acid solution of about 3 pH, adding hydrogen peroxide to precipitate uranium and thorium peroxide, treating the peroxides with sodium hydroxide to selectively precipitate the uranium peroxide, and reacting the separated solution with nitric acid to re- precipitate the uranium peroxide.

  13. Thermal well-test method

    DOEpatents

    Tsang, Chin-Fu; Doughty, Christine A.

    1985-01-01

    A well-test method involving injection of hot (or cold) water into a groundwater aquifer, or injecting cold water into a geothermal reservoir. By making temperature measurements at various depths in one or more observation wells, certain properties of the aquifer are determined. These properties, not obtainable from conventional well test procedures, include the permeability anisotropy, and layering in the aquifer, and in-situ thermal properties. The temperature measurements at various depths are obtained from thermistors mounted in the observation wells.

  14. Methods for testing transport models

    SciTech Connect

    Singer, C.; Cox, D.

    1991-11-14

    Substantial progress has been made over the past year on six aspects of the work supported by this grant. As a result, we have in hand for the first time a fairly complete set of transport models and improved statistical methods for testing them against large databases. We also have initial results of such tests. These results indicate that careful application of presently available transport theories can reasonably well produce a remarkably wide variety of tokamak data.

  15. Application of Taguchi Method to Investigate the Effects of Process Factors on the Production of Industrial Piroxicam Polymorphs and Optimization of Dissolution Rate of Powder.

    PubMed

    Shahbazian, Alen; Davood, Asghar; Dabirsiaghi, Alireza

    2016-01-01

    Piroxicam has two different crystalline forms (known as needle and cubic forms), that they are different in physicochemical properties such as biological solubility. In the current research, using Taguchi experimental design approach the influences of five operating variables on formation of the piroxicam polymorph shapes in recrystallization were studied. The variables include type of solvent, cooling methods, type of mixture paddle, pH, and agitator speed. Statistical analysis of results revealed the significance order of factors affecting the product quality and quantity. At first using the Taguchi experimental method, the influence of process factors on the yield, particle size and dissolution rate of piroxicam powder was statistically investigated. The optimum conditions to achieve the best dissolution rate of piroxicam were determined experimentally. The results were analyzed using Qualitek4 software and it was revealed that the type of solvent and method of cooling respectively are the most important factors that affect the dissolution rate. It was also experimentally achieved that some factors such as type of agitator paddle, pH and agitation rate have no significant effects on dissolution rate.

  16. Co-solvent evaporation method for enhancement of solubility and dissolution rate of poorly aqueous soluble drug simvastatin: in vitro-in vivo evaluation.

    PubMed

    Pandya, Priyanka; Gattani, Surendra; Jain, Pankaj; Khirwal, Lokesh; Surana, Sanjay

    2008-01-01

    A number of synthesized chemical molecules suffer from low aqueous solubility problems. Enhancement of aqueous solubility, dissolution rate, and bioavailability of drug is a very challenging task in drug development. In the present study, solubility and dissolution of poorly aqueous soluble drug simvastatin (SIM) was enhanced using hydrophilic, low viscosity grade polymer hydroxypropyl methylcellulose (HPMC K(3)LV). The co-solvent evaporation method was developed for efficient encapsulation of hydrophobic drug in polymer micelles of HPMC K(3)LV. Spray drying and rotaevaporation method were applied for solvent evaporation. Co-solvent-evaporated mixture in solid state was determined by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD), scanning electron microscopy, and Fourier-transform infrared spectroscopy. In vitro-in vivo studies were performed on co-solvent-evaporated mixture and compared with SIM. In vivo study was conducted on healthy albino rats (Wister strain), and formulations were administered by oral route. Results of the study show the conversion of crystalline form of SIM into amorphous form. The dissolution rate was remarkably increased in co-solvent-evaporated mixtures compared to SIM. co-solvent-evaporated mixtures showed better reduction in total cholesterol and triglyceride levels than the SIM. The low-viscosity grade HPMC acts as a surfactant, which enhances the wetting of drug and thus improves the solubility of drug. The co-solvent evaporation method provides good encapsulation efficiency and produces amorphous form of SIM, which gave better solubility and dissolution than the crystalline SIM.

  17. Application of Taguchi Method to Investigate the Effects of Process Factors on the Production of Industrial Piroxicam Polymorphs and Optimization of Dissolution Rate of Powder.

    PubMed

    Shahbazian, Alen; Davood, Asghar; Dabirsiaghi, Alireza

    2016-01-01

    Piroxicam has two different crystalline forms (known as needle and cubic forms), that they are different in physicochemical properties such as biological solubility. In the current research, using Taguchi experimental design approach the influences of five operating variables on formation of the piroxicam polymorph shapes in recrystallization were studied. The variables include type of solvent, cooling methods, type of mixture paddle, pH, and agitator speed. Statistical analysis of results revealed the significance order of factors affecting the product quality and quantity. At first using the Taguchi experimental method, the influence of process factors on the yield, particle size and dissolution rate of piroxicam powder was statistically investigated. The optimum conditions to achieve the best dissolution rate of piroxicam were determined experimentally. The results were analyzed using Qualitek4 software and it was revealed that the type of solvent and method of cooling respectively are the most important factors that affect the dissolution rate. It was also experimentally achieved that some factors such as type of agitator paddle, pH and agitation rate have no significant effects on dissolution rate. PMID:27642310

  18. Effects of the Preparation Method on the Formation of True Nimodipine SBE-β-CD/HP-β-CD Inclusion Complexes and Their Dissolution Rates Enhancement.

    PubMed

    Semcheddine, Farouk; Guissi, Nida El Islem; Liu, XueYin; Wu, ZuoMin; Wang, Bo

    2015-06-01

    The aims of this study were to enhance the solubility and dissolution rate of nimodipine (ND) by preparing the inclusion complexes of ND with sulfobutylether-b-cyclodextrin (SBE-β-CD) and 2-hydroxypropyl-b-cyclodextrin (HP-β-CD) and to study the effect of the preparation method on the in vitro dissolution profile in different media (0.1 N HCl pH 1.2, phosphate buffer pH 7.4, and distilled water). Thus, the inclusion complexes were prepared by kneading, coprecipitation, and freeze-drying methods. Phase solubility studies were conducted to characterize the complexes in the liquid state. The inclusion complexes in the solid state were investigated with differential scanning calorimetry (DSC), X-ray diffractometry (X-RD), and Fourier transform infrared spectroscopy (FT-IR). Stable complexes of ND/SBE-β-CD and ND/HP-β-CD were formed in distilled water in a 1:1 stoichiometric inclusion complex as indicated by an AL-type diagram. The apparent stability constants (Ks) were 1334.4 and 464.1 M(-1) for ND/SBE-β-CD and ND/HP-β-CD, respectively. The water-solubility of ND was significantly increased in an average of 22- and 8-fold for SBE-β-CD and HP-β-CD, respectively. DSC results showed the formation of true inclusion complexes between the drug and both SBE-β-CD and HP-β-CD prepared by the kneading method. In contrast, crystalline drug was detectable in all other products. The dissolution studies showed that all the products exhibited higher dissolution rate than those of the physical mixtures and ND alone, in all mediums. However, the kneading complexes displayed the maximum dissolution rate in comparison with drug and other complexes, confirming the influence of the preparation method on the physicochemical properties of the products.

  19. A dynamic system for the simulation of fasting luminal pH-gradients using hydrogen carbonate buffers for dissolution testing of ionisable compounds.

    PubMed

    Garbacz, Grzegorz; Kołodziej, Bartosz; Koziolek, Mirko; Weitschies, Werner; Klein, Sandra

    2014-01-23

    The hydrogen carbonate buffer is considered as the most biorelevant buffer system for the simulation of intestinal conditions and covers the physiological pH range of the luminal fluids from pH 5.5 to about pH 8.4. The pH value of a hydrogen carbonate buffer is the result of a complex and dynamic interplay of the concentration of hydrogen carbonate ions, carbonic acid, the concentration of dissolved and solvated carbon dioxide and its partial pressure above the solution. The complex equilibrium between the different ions results in a thermodynamic instability of hydrogen carbonate solutions. In order to use hydrogen carbonate buffers with pH gradients in the physiological range and with the dynamics observed in vivo without changing the ionic strength of the solution, we developed a device (pHysio-grad®) that provides both acidification of the dissolution medium by microcomputer controlled carbon dioxide influx and alkalisation by degassing. This enables a continuous pH control and adjustment during dissolution of ionisable compounds. The results of the pH adjustment indicate that the system can compensate even rapid pH changes after addition of a basic or acidic moiety in amounts corresponding up to 90% of the overall buffer capacity. The results of the dissolution tests performed for a model formulation containing ionizable compounds (Nexium 20mg mups) indicate that both the simulated fasting intraluminal pH-profiles and the buffer species can significantly affect the dissolution process by changing the lag time prior to initial drug release and the release rate of the model compound. A prediction of the in vivo release behaviour of this formulation is thus most likely strongly related to the test conditions such as pH and buffer species.

  20. Studies on the dissolution of glucose in ionic liquids and extraction using the antisolvent method.

    PubMed

    Hassan, El-Sayed R E; Mutelet, Fabrice; Pontvianne, Steve; Moïse, Jean-Charles

    2013-03-19

    Biomass, the fibrous material derived from plant cell walls, is a potentially clean and renewable nonfood feedstock for liquid fuel and chemical production in future biorefineries. The capability of ionic liquids to act as selective solvents and catalysts for biomass processing has already been proven. Thus, they are considered as an alternative to conventional solvents. Nevertheless, phase equilibria with biomass derived compounds is still lacking in the literature. To overcome the lack of experimental data on phase equilibria of biomass carbohydrates in ionic liquids, the solubility of d-glucose in four ionic liquids was measured within a temperature range from 283 to 373 K. Solubility data were successfully correlated with local composition thermodynamic models such as NRTL and UNIQUAC. In this work, the possibility of extracting glucose from these ionic liquids using the antisolvent method has been also evaluated. The parameters affecting the extraction process are the ionic liquid type, ethanol/ionic liquid ratio, temperature, water content, and time. Results indicate that ethanol can be successfully used as an antisolvent to separate glucose from ionic liquids. PMID:23398175

  1. K Basin Sludge Conditioning Process Testing Fate of PCBs During K Basin Sludge Dissolution in Nitric Acid and with Hydrogen Peroxide Addition

    SciTech Connect

    GM Mong; AJ Schmidt; EW Hoppe; KH Pool; KL Silvers; BM Thornton

    1999-01-04

    The work described in this report is part of the studies being performed to address the fate of polychlorinated biphenyls (PCBs) in K Basin sludge before the sludge can be transferred to the Tank Waste Remediation System (TWRS) double shell tanks. One set of tests examined the effect of hydrogen peroxide on the disposition of PCBs in a simulated K Basin dissolver solution containing 0.5 M nitric acid/1 M Fe(NO{sub 3}){sub 3}. A second series of tests examined the disposition of PCBs in a much stronger ({approx}10 M) nitric acid solution, similar to that likely to be encountered in the dissolution of the sludge.

  2. Thermal well-test method

    DOEpatents

    Tsang, C.F.; Doughty, C.A.

    1984-02-24

    A well-test method involving injection of hot (or cold) water into a groundwater aquifer, or injecting cold water into a geothermal reservoir is disclosed. By making temperature measurements at various depths in one or more observation wells, certain properties of the aquifer are determined. These properties, not obtainable from conventional well test procedures, include the permeability anisotropy, and layering in the aquifer, and in-situ thermal properties. The temperature measurements at various depths are obtained from thermistors mounted in the observation wells.

  3. Special Test Methods for Batteries

    NASA Technical Reports Server (NTRS)

    Gross, S.

    1984-01-01

    Various methods are described for measuring heat generation in primary and secondary batteries as well as the specific heat of batteries and cell thermal conductance. Problems associated with determining heat generation in large batteries are examined. Special attention is given to monitoring temperature gradients in nickel cadmium cells, the use of auxiliary electrodes for conducting tests on battery charge control, evaluating the linear sweep of current from charge to discharge, and determining zero current voltage. The fast transient behavior of batteries in the microsecond range, and the electrical conductance of nickel sinters in the thickness direction are also considered. Mechanical problems experienced in the vibration of Ni-Cd batteries and tests to simulate cyclic fatigue of the steel table connecting the plates to the comb are considered. Methods of defining the distribution of forces when cells are compressed during battery packaging are also explored.

  4. Impact of vibration and agitation speed on dissolution of USP prednisone tablets RS and various IR tablet formulations.

    PubMed

    Seeger, Nicole; Lange, Sigrid; Klein, Sandra

    2015-08-01

    Dissolution testing is an in vitro procedure which is widely used in quality control (QC) of solid oral dosage forms and, given that real biorelevant test conditions are applied, can also be used as a predictive tool for the in vivo performance of such formulations. However, if a dissolution method is intended to be used for such purposes, it has to deliver results that are only determined by the quality of the test product, but not by other variables. In the recent past, more and more questions were arising on how to address the effects of vibration on dissolution test results. The present study was performed to screen for the correlation of prednisone dissolution of USP Prednisone Tablets RS with vibration caused by a commercially available vibration source as well as to investigate how drug release from a range of immediate release formulations containing class 1-4 drugs of the biopharmaceutical classification scheme is affected by vibration when performing dissolution experiments at different agitation rates. Results of the present study show that the dissolution process of oral drug formulations can be affected by vibration. However, it also becomes clear that the degree of which a certain level of vibration impacts dissolution is strongly dependent on several factors such as drug properties, formulation parameters, and the design of the dissolution method. To ensure the establishment of robust and predictive dissolution test methods, the impact of variation should thus be considered in method design and validation.

  5. Understanding the impact of media viscosity on dissolution of a highly water soluble drug within a USP 2 mini vessel dissolution apparatus using an optical planar induced fluorescence (PLIF) method.

    PubMed

    Stamatopoulos, Konstantinos; Batchelor, Hannah K; Alberini, Federico; Ramsay, John; Simmons, Mark J H

    2015-11-10

    In this study, planar induced fluorescence (PLIF) was used for the first time to evaluate variability in drug dissolution data using Rhodamine-6G doped tablets within small volume USP 2 apparatus. The results were compared with tablets contained theophylline (THE) drug for conventional dissolution analysis. The impact of hydrodynamics, sampling point, dissolution media viscosity and pH were investigated to note effects on release of these two actives from the hydrophilic matrix tablets. As expected mixing performance was poor with complex and reduced velocities at the bottom of the vessel close to the tablet surface; this mixing became even worse as the viscosity of the fluid increased. The sampling point for dissolution can affect the results due to in-homogenous mixing within the vessel; this effect is exacerbated with higher viscosity dissolution fluids. The dissolution profiles of RH-6G measured via PLIF and THE measured using UV analysis were not statistically different demonstrating that RH-6G is an appropriate probe to mimic the release profile of a highly soluble drug. A linear correlation was accomplished between the release data of the drug and the dye (R(2)>0.9). The dissolution profile of the dye, obtained with the analysis of the PLIF images, can be used in order to evaluate how the viscosity and the mixing performance of USP 2 mini vessel affect the interpretation of the dissolution data of the targeted drug.

  6. Enzymatic activity in the presence of surfactants commonly used in dissolution media, Part 1: Pepsin

    PubMed Central

    Guzman, Maria L; Marques, Margareth R; Olivera ME, Maria E; Stippler, Erika S

    2016-01-01

    The United States Pharmacopeia (USP) General Chapters Dissolution 〈711〉 and Disintegration and Dissolution of Dietary Supplements 〈2040〉 allows the use of enzymes in dissolution media when gelatin capsules do not conform to dissolution specifications due to cross linking. Possible interactions between enzymes and surfactants when used together in dissolution media could result in loss of the enzymatic activity. Pepsin is an enzyme commonly used in dissolution media, and in this work, the activity of pepsin was determined in the presence of different surfactants as usually found in case of dissolution tests of certain gelatin capsule formulations. Pepsin enzymatic activity was determined according to the Ninth Edition of the Food Chemicals Codex (FCC) 9 method, in dissolution conditions: simulated gastric fluid, 37 °C and 50 rpm. Sodium dodecyl sulfate (SDS), cetyltrimethyl ammonium bromide (CTAB), polysorbate 80 (Tween 80) and octoxynol 9 (Triton X100) in concentrations above and below their critical micellar concentrations were selected. Results showed a significant reduction in the activity of pepsin at all the concentrations of SDS assayed. On the contrary, CTAB, Tween 80, and Triton X100 did not alter the enzymatic activity at of pepsin any of the concentration assayed. This data demonstrates a rational selection of the surfactant to be used when pepsin is required in dissolution test. PMID:27047734

  7. 40 CFR 63.1161 - Performance testing and test methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... concentration standard for that plant. (d) Test methods. (1) The following test methods in appendix A of 40 CFR... Facilities and Hydrochloric Acid Regeneration Plants § 63.1161 Performance testing and test methods. (a...) or measure the concentration of HCl (and Cl2 for hydrochloric acid regeneration plants) in...

  8. 40 CFR 63.1161 - Performance testing and test methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... concentration standard for that plant. (d) Test methods. (1) The following test methods in appendix A of 40 CFR... Facilities and Hydrochloric Acid Regeneration Plants § 63.1161 Performance testing and test methods. (a...) or measure the concentration of HCl (and Cl2 for hydrochloric acid regeneration plants) in...

  9. 40 CFR 63.1161 - Performance testing and test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... concentration standard for that plant. (d) Test methods. (1) The following test methods in appendix A of 40 CFR... Facilities and Hydrochloric Acid Regeneration Plants § 63.1161 Performance testing and test methods. (a...) or measure the concentration of HCl (and Cl2 for hydrochloric acid regeneration plants) in...

  10. 49 CFR 383.133 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 5 2011-10-01 2011-10-01 false Test methods. 383.133 Section 383.133... STANDARDS; REQUIREMENTS AND PENALTIES Tests § 383.133 Test methods. (a) All tests must be constructed in...) Knowledge tests: (1) States must use the FMCSA pre-approved pool of test questions to develop...

  11. Development of a biphasic dissolution test for Deferasirox dispersible tablets and its application in establishing an in vitro-in vivo correlation.

    PubMed

    Al Durdunji, Amal; AlKhatib, Hatim S; Al-Ghazawi, Mutasim

    2016-05-01

    In a biphasic dissolution medium, the integration of the in vitro dissolution of a drug in an aqueous phase and its subsequent partitioning into an organic phase is hypothesized to simulate the in vivo drug absorption. Such a methodology is expected to improve the probability of achieving a successful in vitro-in vivo correlation. Dissolution of Dispersible tablets of Deferasirox, a biopharmaceutics classification system type II compound, was studied in a biphasic dissolution medium using a flow-through dissolution apparatus coupled to a paddle apparatus. The experimental parameters associated with dissolution were optimized to discriminate between Deferasirox dispersible tablets of different formulations. The dissolution profiles obtained from this system were subsequently used to construct a level A in vitro-in vivo correlation.

  12. Characterization and evaluation of a modified PVPA barrier in comparison to Caco-2 cell monolayers for combined dissolution and permeation testing.

    PubMed

    Gantzsch, Sandra P; Kann, Birthe; Ofer-Glaessgen, Monika; Loos, Petra; Berchtold, Harald; Balbach, Stefan; Eichinger, Thomas; Lehr, Claus-Michael; Schaefer, Ulrich F; Windbergs, Maike

    2014-02-10

    Aim of this study was to implement a modified phospholipid vesicle-based permeation assay (PVPA) barrier as alternative to Caco-2 cell monolayers in a combined dissolution and permeation system for testing of solid dosage forms. Commercially available Transwell® inserts were coated with egg phospholipids (Lipoid E 80) and characterized by confocal Raman microscopy. The modified PVPA barrier was then evaluated in permeation studies with solutions of different drugs as well as in combined dissolution and permeation studies utilizing an immediate and an extended release tablet formulation. Raman cross section images demonstrated complete filling of the membrane pores with lipids and the formation of a continuous lipid layer of increasing thickness on top of the membrane during the stepwise coating procedure. Furthermore, it could be shown that this lipid coating remains intact for at least 18h under dynamic flow conditions, significantly exceeding the viability of Caco-2 cell monolayers. Permeability data for both drug solutions as well as for a fast and slow release tablet formulation were in excellent correlation with those data obtained for Caco-2 cell monolayers. Especially under the dynamic flow conditions prevailing in such a setup, the modified PVPA barrier is more robust and easier to handle than epithelial cell monolayers and can be prepared rather easily at a fraction of costs and time. The modified PVPA barrier may therefore represent a valuable alternative to Caco-2 cell monolayers in such context. PMID:24361370

  13. A novel method of non-violent dissolution of sodium metal in a concentrated aqueous solution of Epsom salt

    NASA Astrophysics Data System (ADS)

    Lakshmanan, A. R.; Prasad, M. V. R.; Ponraju, D.; Krishnan, H.

    2004-10-01

    A new technique of non-violent and fast dissolution of sodium metal in a concentrated aqueous solution of Epsom salt (MgSO4.7H2O) at room temperature (RT) has been developed. The dissolution process is mildly exothermic but could be carried out even in a glass beaker in air under swift stirring condition. The reaction products consist of mixed salts of MgSO4 and Na2SO4 as well as Mg(OH)2 which are only mildly alkaline and hence are non-corrosive and non-hazardous unlike NaOH. A 50 mL solution having Epsom salt concentration of 2 M was found to give the optimal composition for disposal of 1 g of sodium. Supersaturated (>2.7 M), as well as dilute (<1.1 M) solutions, however, cause violent reactions and hence should be avoided. Repeated sodium dissolution in Epsom solution produced a solid waste of 4.7 g per g of sodium dissolved which is comparable with the waste (4 g) produced in 8 M NaOH solution. A 1.4 M Epsom solution sprayed with a high-pressure jet cleaner at RT in air easily removed the sodium blocked inside a metal pipe made of mild steel. The above jet also dissolved peacefully residual sodium collected on the metal tray after a sodium fire experiment. No sodium fire or explosion was observed during this campaign. The Epsom solution spray effectively neutralized the minor quantity of sodium aerosol produced during this campaign. This novel technique would hence be quite useful for draining sodium from fast breeder reactor components and bulk processing of sodium as well as for sodium fire fighting.

  14. 40 CFR 63.1161 - Performance testing and test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... (1) The following test methods in appendix A of 40 CFR part 60 shall be used to determine compliance... Facilities and Hydrochloric Acid Regeneration Plants § 63.1161 Performance testing and test methods. (a...) Establishment of hydrochloric acid regeneration plant operating parameters. (1) During the performance test...

  15. 40 CFR 63.1161 - Performance testing and test methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    .... (1) The following test methods in appendix A of 40 CFR part 60 shall be used to determine compliance... Facilities and Hydrochloric Acid Regeneration Plants § 63.1161 Performance testing and test methods. (a...) Establishment of hydrochloric acid regeneration plant operating parameters. (1) During the performance test...

  16. Mechanistic modelling and mechanistic monitoring: simulation and shadowgraph imaging of particulate dissolution in the flow-through apparatus.

    PubMed

    D'arcy, Deirdre M; Persoons, Tim

    2011-03-01

    Accurate mechanistic modelling of a complex system requires insight into the process being simulated, in addition to a theoretical 'first-principles' approach. The current work uses a numerical mechanistic model to simulate dissolution of a particulate system in the flow-through dissolution apparatus. A shadowgraph imaging method is also used to monitor the dissolution process, providing real-time estimates of particle motion, number and total dissolution time. Experimental dissolution studies of ibuprofen particles are used to assess the accuracy of the model. The numerical model adequately predicts the ibuprofen particle dissolution rate at 16 mL min(-1) . Parameter sensitivity analysis identified dissolution test circumstances requiring more, or less, accuracy in the particle size and density calculations. The shadowgraph imaging method successfully determined the total dissolution time and decreasing particle numbers over time. The images confirmed the pulsing particle motion of the numerical model but revealed some more complex velocity patterns, assisting numerical model development. Further optimisation of the sampling window is required to capture all relevant particle motion and changing particle size distribution. A mechanistic model can successfully simulate particulate dissolution in the flow-through apparatus, and when used along with shadowgraph imaging, can give valuable insight into the dissolution process mechanisms and environment. PMID:20848646

  17. Error response test system and method using test mask variable

    NASA Technical Reports Server (NTRS)

    Gender, Thomas K. (Inventor)

    2006-01-01

    An error response test system and method with increased functionality and improved performance is provided. The error response test system provides the ability to inject errors into the application under test to test the error response of the application under test in an automated and efficient manner. The error response system injects errors into the application through a test mask variable. The test mask variable is added to the application under test. During normal operation, the test mask variable is set to allow the application under test to operate normally. During testing, the error response test system can change the test mask variable to introduce an error into the application under test. The error response system can then monitor the application under test to determine whether the application has the correct response to the error.

  18. Smoothing Methods for Estimating Test Score Distributions.

    ERIC Educational Resources Information Center

    Kolen, Michael J.

    1991-01-01

    Estimation/smoothing methods that are flexible enough to fit a wide variety of test score distributions are reviewed: kernel method, strong true-score model-based method, and method that uses polynomial log-linear models. Applications of these methods include describing/comparing test score distributions, estimating norms, and estimating…

  19. Myasthenia Gravis: Tests and Diagnostic Methods

    MedlinePlus

    ... Affiliations Foundation Focus Newsletter E-Update Test & Diagnostic methods In addition to a complete medical and neurological ... How can I help? About MGFA Test & Diagnostic methods Treatment for MG FAQ's Upcoming Events Spring 2016 ...

  20. Fundamental study of photoresist dissolution with real time spectroscopic ellipsometry and interferometry

    NASA Astrophysics Data System (ADS)

    Burns, Sean D.; Schmid, Gerard M.; Trinque, Brian C.; Willson, James; Wunderlich, Jennifer; Tsiartas, Pavlos C.; Taylor, James C.; Burns, Ryan L.; Wilson, C. Grant

    2003-06-01

    The use of in situ spectroscopic ellipsometry (SE) is demonstrated as a technique for studying photoresist dissolution. Experiments carried out using a J.A.Woollam M-2000 ellipsometer and a custom built cell designed for in situ film measurements show that bulk dissolution rate measurements using the SE technique agree with dissolution rate data obtained using multiwavelength interferometry. SE is also demonstrated as a method for measuring thin film dissolution rates, water sorption, and films that swell. An additional focus of this work was the topic of interfacial "gel" layer formation during photoresist dissolution. Ellipsometry and interferometry were used to test several photoresist resins, with an emphasis on phenolic polymers. Single and multiple layer models were used to analyze the data, and were compared to model calculations predicting formation of a gel layer. For the materials studied, interfacial gel layer formation in low molecular weight phenolic polymers was not detected, within the resolution of the experimental techniques (< 15 nm).

  1. 30 CFR 27.31 - Testing methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Testing methods. 27.31 Section 27.31 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test Requirements § 27.31 Testing methods. A...

  2. 30 CFR 27.31 - Testing methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Testing methods. 27.31 Section 27.31 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test Requirements § 27.31 Testing methods. A...

  3. 30 CFR 27.31 - Testing methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Testing methods. 27.31 Section 27.31 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test Requirements § 27.31 Testing methods. A...

  4. 30 CFR 27.31 - Testing methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Testing methods. 27.31 Section 27.31 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test Requirements § 27.31 Testing methods. A...

  5. 40 CFR 80.3 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Test methods. 80.3 Section 80.3... FUELS AND FUEL ADDITIVES General Provisions § 80.3 Test methods. The lead and phosphorus content of gasoline shall be determined in accordance with test methods set forth in the appendices to this part....

  6. 40 CFR 80.3 - Test methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Test methods. 80.3 Section 80.3... FUELS AND FUEL ADDITIVES General Provisions § 80.3 Test methods. The lead and phosphorus content of gasoline shall be determined in accordance with test methods set forth in the appendices to this part....

  7. 40 CFR 63.465 - Test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 10 2014-07-01 2014-07-01 false Test methods. 63.465 Section 63.465... Halogenated Solvent Cleaning § 63.465 Test methods. (a) Except as provided in paragraphs (f) and (g) of this...) of this section. (i) From tests conducted using EPA reference method 25d. (ii) By...

  8. 40 CFR 63.1546 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 12 2011-07-01 2009-07-01 true Test methods. 63.1546 Section 63.1546... Hazardous Air Pollutants for Primary Lead Smelting § 63.1546 Test methods. (a) The following procedure shall....1543(a)(1) through § 63.1543(a)(9) shall be determined according to the following test methods...

  9. 40 CFR 80.3 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Test methods. 80.3 Section 80.3... FUELS AND FUEL ADDITIVES General Provisions § 80.3 Test methods. The lead and phosphorus content of gasoline shall be determined in accordance with test methods set forth in the appendices to this part....

  10. 40 CFR 63.1546 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 12 2010-07-01 2010-07-01 true Test methods. 63.1546 Section 63.1546... Hazardous Air Pollutants for Primary Lead Smelting § 63.1546 Test methods. (a) The following procedure shall....1543(a)(1) through § 63.1543(a)(9) shall be determined according to the following test methods...

  11. Electrokinetic remediation prefield test methods

    NASA Technical Reports Server (NTRS)

    Hodko, Dalibor (Inventor)

    2000-01-01

    Methods for determining the parameters critical in designing an electrokinetic soil remediation process including electrode well spacing, operating current/voltage, electroosmotic flow rate, electrode well wall design, and amount of buffering or neutralizing solution needed in the electrode wells at operating conditions are disclosed These methods are preferably performed prior to initiating a full scale electrokinetic remediation process in order to obtain efficient remediation of the contaminants.

  12. Bacterial mutagenicity assays: test methods.

    PubMed

    Gatehouse, David

    2012-01-01

    The most widely used assays for detecting chemically induced gene mutations are those employing bacteria. The plate incorporation assay using various Salmonella typhimurium LT2 and E. coli WP2 strains is a short-term bacterial reverse mutation assay specifically designed to detect a wide range of chemical substances capable of causing DNA damage leading to gene mutations. The test is used worldwide as an initial screen to determine the mutagenic potential of new chemicals and drugs.The test uses several strains of S. typhimurium which carry different mutations in various genes of the histidine operon, and E. coli which carry the same AT base pair at the critical mutation site within the trpE gene. These mutations act as hot spots for mutagens that cause DNA damage via different mechanisms. When these auxotrophic bacterial strains are grown on a minimal media agar plates containing a trace of the required amino-acid (histidine or tryptophan), only those bacteria that revert to amino-acid independence (His(+) or Tryp(+)) will grow to form visible colonies. The number of spontaneously induced revertant colonies per plate is relatively constant. However, when a mutagen is added to the plate, the number of revertant colonies per plate is increased, usually in a dose-related manner.This chapter provides detailed procedures for performing the test in the presence and absence of a metabolic activation system (S9-mix), including advice on specific assay variations and any technical problems. PMID:22147566

  13. METHOD OF TESTING FOR LEAKS

    DOEpatents

    Creutz, E.C.; McAdams, Wm.A.; Foss, M.H.

    1958-07-22

    A method is described for detecting minute holes In fuel element jackets. The method comprises submerging the jacketed body in an atmosphere of a radioactive gas under pressure, the radioactive emanations from said gas being sufficientiy penetratIng to penetrate the jacket of the jacketed body. After the jacketed body is removed from the radtoactive gas atmosphere, it is exannined for the presence of emanations from radioactive gas which entered the jacketed body through the minute holes. In this manner, the detectton of radioactive emanations is a positive indication that the fuel element is not perfectly sealed.

  14. 7 CFR 58.644 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 3 2011-01-01 2011-01-01 false Test methods. 58.644 Section 58.644 Agriculture... Procedures § 58.644 Test methods. (a) Microbiological. Microbiological determinations shall be made in accordance with the methods described in the latest edition of Standard Methods for the Examination of...

  15. 7 CFR 58.644 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Test methods. 58.644 Section 58.644 Agriculture... Procedures § 58.644 Test methods. (a) Microbiological. Microbiological determinations shall be made in accordance with the methods described in the latest edition of Standard Methods for the Examination of...

  16. 30 CFR 36.41 - Testing methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Testing methods. 36.41 Section 36.41 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF... Requirements § 36.41 Testing methods. Mobile diesel-powered transportation equipment submitted...

  17. 16 CFR 1513.4 - Test methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Test methods. 1513.4 Section 1513.4... REQUIREMENTS FOR BUNK BEDS § 1513.4 Test methods. (a) Guardrails (see § 1513.3(a)(6)). With no mattress on the... manufacturer's recommended maximum thickness mattress and foundation in place, repeat the test in paragraph...

  18. 16 CFR 1213.4 - Test methods.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Test methods. 1213.4 Section 1213.4... STANDARD FOR ENTRAPMENT HAZARDS IN BUNK BEDS § 1213.4 Test methods. (a) Guardrails (see § 1213.3(a)(6... manufacturer's recommended maximum thickness mattress and foundation in place, repeat the test in paragraph...

  19. 30 CFR 36.41 - Testing methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Testing methods. 36.41 Section 36.41 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF... Requirements § 36.41 Testing methods. Mobile diesel-powered transportation equipment submitted...

  20. 40 CFR 59.207 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Consumer Products § 59.207 Test methods. Each manufacturer or...

  1. 40 CFR 59.207 - Test methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Consumer Products § 59.207 Test methods. Each manufacturer or...

  2. 40 CFR 59.207 - Test methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Consumer Products § 59.207 Test methods. Each manufacturer or...

  3. 40 CFR 59.207 - Test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... VOLATILE ORGANIC COMPOUND EMISSION STANDARDS FOR CONSUMER AND COMMERCIAL PRODUCTS National Volatile Organic Compound Emission Standards for Consumer Products § 59.207 Test methods. Each manufacturer or...

  4. RELATIVE DISSOLUTION RATES OF RADIOACTIVE MATERIALS USED AT AWE.

    PubMed

    Miller, T J; Bingham, D; Cockerill, R; Waldren, S; Moth, N

    2016-09-01

    A simple in vitro dissolution test was used to provide a semi-quantitative comparison of the relative dissolution rates of samples of radioactive materials used at Atomic Weapons Establishment in a lung fluid surrogate (Ringer's solution). A wide range of dissolution rates were observed for aged legacy actinides, freshly produced actinide alloys and actinides from waste management operations.

  5. YUCCA Mountain Project - Argonne National Laboratory, Annual Progress Report, FY 1997 for activity WP 1221 unsaturated drip condition testing of spent fuel and unsaturated dissolution tests of glass.

    SciTech Connect

    Bates, J. K.; Buck, E. C.; Emery, J. W.; Finch, R. J.; Finn, P. A.; Fortner, J.; Hoh, J. C.; Mertz, C.; Neimark, L. A.; Wolf, S. F.; Wronkiewicz, D. J.

    1998-09-18

    This document reports on the work done by the Nuclear Waste Management Section of the Chemical Technology Division of Argonne National Laboratory in the period of October 1996 through September 1997. Studies have been performed to evaluate the behavior of nuclear waste glass and spent fuel samples under the unsaturated conditions (low-volume water contact) that are likely to exist in the Yucca Mountain environment being considered as a potential site for a high-level waste repository. Tests with actinide-doped waste glasses, in progress for over 11 years, indicate that the transuranic element release is dominated by colloids that continuously form and span from the glass surface. The nature of the colloids that form in the glass and spent fuel testing programs is being investigated by dynamic light scattering to determine the size distribution, by autoradiography to determine the chemistry, and by zeta potential to measure the electrical properties of the colloids. Tests with UO{sub 2} have been ongoing for 12 years. They show that the oxidation of UO{sub 2} occurs rapidly, and the resulting paragenetic sequence of secondary phases forming on the sample surface is similar to that observed for uranium found in natural oxidizing environments. The reaction of spent fuel samples in conditions similar to those used with UO{sub 2} have been in progress for over six years, and the results suggest that spent fuel forms many of the same alteration products as UO{sub 2}. With spent fuel, the bulk of the reaction occurs via a through-grain reaction process, although grain boundary attack is sufficient to have reacted all of the grain boundary regions in the samples. New test methods are under development to evaluate the behavior of spent fuel samples with intact cladding: the rate at which alteration and radionuclide release occurs when water penetrates fuel sections and whether the reaction causes the cladding to split. Alteration phases have been formed on fine grains of UO

  6. Nanosizing of drugs: Effect on dissolution rate

    PubMed Central

    Dizaj, S. Maleki; Vazifehasl, Zh.; Salatin, S.; Adibkia, Kh.; Javadzadeh, Y.

    2015-01-01

    The solubility, bioavailability and dissolution rate of drugs are important parameters for achieving in vivo efficiency. The bioavailability of orally administered drugs depends on their ability to be absorbed via gastrointestinal tract. For drugs belonging to Class II of pharmaceutical classification, the absorption process is limited by drug dissolution rate in gastrointestinal media. Therefore, enhancement of the dissolution rate of these drugs will present improved bioavailability. So far several techniques such as physical and chemical modifications, changing in crystal habits, solid dispersion, complexation, solubilization and liquisolid method have been used to enhance the dissolution rate of poorly water soluble drugs. It seems that improvement of the solubility properties ofpoorly water soluble drugscan translate to an increase in their bioavailability. Nowadays nanotechnology offers various approaches in the area of dissolution enhancement of low aqueous soluble drugs. Nanosizing of drugs in the form of nanoparticles, nanocrystals or nanosuspensions not requiring expensive facilities and equipment or complicated processes may be applied as simple methods to increase the dissolution rate of poorly water soluble drugs. In this article, we attempted to review the effects of nanosizing on improving the dissolution rate of poorly aqueous soluble drugs. According to the reviewed literature, by reduction of drug particle size into nanometer size the total effective surface area is increased and thereby dissolution rate would be enhanced. Additionally, reduction of particle size leads to reduction of the diffusion layer thickness surrounding the drug particles resulting in the increment of the concentration gradient. Each of these process leads to improved bioavailability. PMID:26487886

  7. PE Metrics: Background, Testing Theory, and Methods

    ERIC Educational Resources Information Center

    Zhu, Weimo; Rink, Judy; Placek, Judith H.; Graber, Kim C.; Fox, Connie; Fisette, Jennifer L.; Dyson, Ben; Park, Youngsik; Avery, Marybell; Franck, Marian; Raynes, De

    2011-01-01

    New testing theories, concepts, and psychometric methods (e.g., item response theory, test equating, and item bank) developed during the past several decades have many advantages over previous theories and methods. In spite of their introduction to the field, they have not been fully accepted by physical educators. Further, the manner in which…

  8. 16 CFR 1213.4 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Test methods. 1213.4 Section 1213.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION CONSUMER PRODUCT SAFETY ACT REGULATIONS SAFETY STANDARD FOR ENTRAPMENT HAZARDS IN BUNK BEDS § 1213.4 Test methods. (a) Guardrails (see §...

  9. 16 CFR 1513.4 - Test methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Test methods. 1513.4 Section 1513.4 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR BUNK BEDS § 1513.4 Test methods. (a) Guardrails (see § 1513.3(a)(6)). With no mattress on...

  10. 40 CFR 80.3 - Test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Test methods. 80.3 Section 80.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES General Provisions § 80.3 Test methods. The lead and phosphorus content...

  11. 40 CFR 80.3 - Test methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Test methods. 80.3 Section 80.3 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGULATION OF FUELS AND FUEL ADDITIVES General Provisions § 80.3 Test methods. The lead and phosphorus content...

  12. 40 CFR 59.207 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 5 2010-07-01 2010-07-01 false Test methods. 59.207 Section 59.207 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) NATIONAL... Compound Emission Standards for Consumer Products § 59.207 Test methods. Each manufacturer or...

  13. Methods for Scaling Icing Test Conditions

    NASA Technical Reports Server (NTRS)

    Anderson, David N.

    1995-01-01

    This report presents the results of tests at NASA Lewis to evaluate several methods to establish suitable alternative test conditions when the test facility limits the model size or operating conditions. The first method was proposed by Olsen. It can be applied when full-size models are tested and all the desired test conditions except liquid-water content can be obtained in the facility. The other two methods discussed are: a modification of the French scaling law and the AEDC scaling method. Icing tests were made with cylinders at both reference and scaled conditions representing mixed and glaze ice in the NASA Lewis Icing Research Tunnel. Reference and scale ice shapes were compared to evaluate each method. The Olsen method was tested with liquid-water content varying from 1.3 to .8 g/m(exp3). Over this range, ice shapes produced using the Olsen method were unchanged. The modified French and AEDC methods produced scaled ice shapes which approximated the reference shapes when model size was reduced to half the reference size for the glaze-ice cases tested.

  14. Fabrication of carvedilol nanosuspensions through the anti-solvent precipitation-ultrasonication method for the improvement of dissolution rate and oral bioavailability.

    PubMed

    Liu, Dandan; Xu, Heming; Tian, Baocheng; Yuan, Kun; Pan, Hao; Ma, Shilin; Yang, Xinggang; Pan, Weisan

    2012-03-01

    The present study aims to prepare carvedilol (CAR) nanosuspensions using the anti-solvent precipitation-ultrasonication technique to improve its dissolution rate and oral bioavailability. Alpha-tocopherol succinate (VES) was first used as a co-stabilizer to enhance the stability of the nanosuspensions. The effects of the process parameters on particle size of the nanosuspensions were investigated. The optimal values of the precipitation temperature, power inputs, and the time length of ultrasonication were selected as 10°C, 400 W, and 15 min, respectively. Response surface methodology based on central composite design was utilized to evaluate the formulation factors that affect the size of nanosuspensions, i.e., the concentration of CAR and VES in the organic solution, and the level of sodium dodecyl sulfate in the anti-solvent phase, respectively. The optimized formulation showed a mean size of 212 ± 12 nm and a zeta potential of -42 ± 3 mV. Scanning electron microscopy revealed that the nanosuspensions were flaky-shaped. Powder X-ray diffraction and differential scanning calorimetry analysis confirmed that the nanoparticles were in the amorphous state. Fourier transform infrared analysis demonstrated that the reaction between CAR and VES is probably due to hydrogen bonding. The nanosuspension was physically stable at 25°C for 1 week, which allows it to be further processing such as drying. The dissolution rate of the nanosuspensions was markedly enhanced by reducing the size. The in vivo test demonstrated that the C(max) and AUC(0-36) values of nanosuspensions were approximately 3.3- and 2.9-fold greater than that of the commercial tablets, respectively. PMID:22246736

  15. Fabrication of carvedilol nanosuspensions through the anti-solvent precipitation-ultrasonication method for the improvement of dissolution rate and oral bioavailability.

    PubMed

    Liu, Dandan; Xu, Heming; Tian, Baocheng; Yuan, Kun; Pan, Hao; Ma, Shilin; Yang, Xinggang; Pan, Weisan

    2012-03-01

    The present study aims to prepare carvedilol (CAR) nanosuspensions using the anti-solvent precipitation-ultrasonication technique to improve its dissolution rate and oral bioavailability. Alpha-tocopherol succinate (VES) was first used as a co-stabilizer to enhance the stability of the nanosuspensions. The effects of the process parameters on particle size of the nanosuspensions were investigated. The optimal values of the precipitation temperature, power inputs, and the time length of ultrasonication were selected as 10°C, 400 W, and 15 min, respectively. Response surface methodology based on central composite design was utilized to evaluate the formulation factors that affect the size of nanosuspensions, i.e., the concentration of CAR and VES in the organic solution, and the level of sodium dodecyl sulfate in the anti-solvent phase, respectively. The optimized formulation showed a mean size of 212 ± 12 nm and a zeta potential of -42 ± 3 mV. Scanning electron microscopy revealed that the nanosuspensions were flaky-shaped. Powder X-ray diffraction and differential scanning calorimetry analysis confirmed that the nanoparticles were in the amorphous state. Fourier transform infrared analysis demonstrated that the reaction between CAR and VES is probably due to hydrogen bonding. The nanosuspension was physically stable at 25°C for 1 week, which allows it to be further processing such as drying. The dissolution rate of the nanosuspensions was markedly enhanced by reducing the size. The in vivo test demonstrated that the C(max) and AUC(0-36) values of nanosuspensions were approximately 3.3- and 2.9-fold greater than that of the commercial tablets, respectively.

  16. Development of new hole expansion testing method

    NASA Astrophysics Data System (ADS)

    Kim, Hyunok; Shang, Jianhui; Beam, Kevin; Samant, Anoop; Hoschouer, Cliff; Dykeman, Jim

    2016-08-01

    This paper introduces a new hole expansion (HE) testing method that could be more relevant to the edge cracking problem observed in stamping advanced high strength steel (AHSS). The new testing method adopted a large hole diameter of 75 mm compared to the standard hole diameter of 10 mm. An inline monitoring system was developed to visually monitor the hole edge cracking during the test and synchronize the load-displacement data with the recorded video for capturing the initial crack. A new hole expansion testing method was found to be effective in evaluating the edge cracking by considering the effects of material properties and trimming methods. It showed a much larger difference, up to 11%, of the HE ratio between DP980 and TRIP780 compared to the standard HE testing method giving less than a 2% difference.

  17. Absorbing Software Testing into the Scrum Method

    NASA Astrophysics Data System (ADS)

    Tuomikoski, Janne; Tervonen, Ilkka

    In this paper we study, how to absorb software testing into the Scrum method. We conducted the research as an action research during the years 2007-2008 with three iterations. The result showed that testing can and even should be absorbed to the Scrum method. The testing team was merged into the Scrum teams. The teams can now deliver better working software in a shorter time, because testing keeps track of the progress of the development. Also the team spirit is higher, because the Scrum team members are committed to the same goal. The biggest change from test manager’s point of view was the organized Product Owner Team. Test manager don’t have testing team anymore, and in the future all the testing tasks have to be assigned through the Product Backlog.

  18. Dissolution enthalpies of cellulose in ionic liquids.

    PubMed

    Parviainen, Helena; Parviainen, Arno; Virtanen, Tommi; Kilpeläinen, Ilkka; Ahvenainen, Patrik; Serimaa, Ritva; Grönqvist, Stina; Maloney, Thaddeus; Maunu, Sirkka Liisa

    2014-11-26

    In this work, interactions between cellulose and ionic liquids were studied calorimetrically and by optical microscopy. Two novel ionic liquids (1,5-Diazabicyclo[4.3.0]non-5-enium propionate and N-methyl-1,5-diazabicyclo[4.3.0]non-5-enium dimethyl phosphate) and 1-ethyl-3-methylimidazolium acetate-water mixtures were used as solvents. Optical microscopy served in finding the extent of dissolution and identifying the dissolution pattern of the cellulose sample. Calorimetric studies identified a peak relating to dissolution of cellulose in solvent. The transition did, however, not indicate complete dissolution, but rather dissolution inside fibre or fibrils. This method was used to study differences between four cellulose samples with different pretreatment or origins.

  19. Dissolution enthalpies of cellulose in ionic liquids.

    PubMed

    Parviainen, Helena; Parviainen, Arno; Virtanen, Tommi; Kilpeläinen, Ilkka; Ahvenainen, Patrik; Serimaa, Ritva; Grönqvist, Stina; Maloney, Thaddeus; Maunu, Sirkka Liisa

    2014-11-26

    In this work, interactions between cellulose and ionic liquids were studied calorimetrically and by optical microscopy. Two novel ionic liquids (1,5-Diazabicyclo[4.3.0]non-5-enium propionate and N-methyl-1,5-diazabicyclo[4.3.0]non-5-enium dimethyl phosphate) and 1-ethyl-3-methylimidazolium acetate-water mixtures were used as solvents. Optical microscopy served in finding the extent of dissolution and identifying the dissolution pattern of the cellulose sample. Calorimetric studies identified a peak relating to dissolution of cellulose in solvent. The transition did, however, not indicate complete dissolution, but rather dissolution inside fibre or fibrils. This method was used to study differences between four cellulose samples with different pretreatment or origins. PMID:25256460

  20. Toxicity test method development in southeast Asia

    SciTech Connect

    McPherson, C.A.

    1995-12-31

    Use of aquatic toxicity tests is relatively new in southeast Asia. As part of the ASEAN-Canada Cooperative Programme on Marine Science -- Phase 2, which includes development of marine environmental criteria, a need for tropical toxicity data was identified. A step-wise approach was used for test method development (simple, acute tests and easily measured endpoints first, then more complex short-term chronic methods), for test specific selection (using species found throughout the region first, and then considering species with narrower geographic distribution), and for integration of quality assurance/quality control (QA/QC) practices into all laboratory activities. Development of test protocols specifically for tropical species included acute and chronic toxicity tests with marine fish, invertebrates and algae. Criteria for test species selection will be reviewed. Method development was based on procedures and endpoints already widely used in North America and Europe (e.g., 96-h LC50 with fish), but adapted for use with tropical species. For example, a bivalve larval development test can use the same endpoints but the duration is only 24 hours. Test method development included research on culture and holding procedures, determination of test conditions (e.g., duration, test containers), and identification of appropriate endpoints. Acute tests with fish and invertebrates were developed first. The next step was development of short-term chronic tests to measure phytoplankton growth, bivalve and echinoderm embryo or larval development, and larval fish growth. The number of species and types of tests was increased in a staged approach, as laboratories became better equipped and personnel gained practical experience. In most cases, method development coincided with training workshops to introduce the principles of toxicity testing.

  1. Testing variance components by two jackknife methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The jacknife method, a resampling technique, has been widely used for statistical tests for years. The pseudo value based jacknife method (defined as pseudo jackknife method) is commonly used to reduce the bias for an estimate; however, sometimes it could result in large variaion for an estmimate a...

  2. Method and apparatus for testing microfilaments

    DOEpatents

    Schleitweiler, Patrick M.; Merten, Jr., Charles W.

    1995-08-01

    A method and apparatus are disclosed for testing tensile strength of microfilaments. Fibers as small as 0.001 inch in diameter and 0.04 inches in length have been tested, although the method and apparatus of the invention are capable of testing fibers of smaller diameter and length. The invention utilizes a method wherein one or both ends of a microfilament is gripped using resin which is softened sufficiently to accept an end of the microfilament and then allowed to harden. The invention also employs the use of a translation stage capable of controlled three-dimensional movement suited to facilitating gripping of the microfilament.

  3. Method and apparatus for testing microfilaments

    DOEpatents

    Schleitweiler, P.M.; Merten, C.W. Jr.

    1995-08-01

    A method and apparatus are disclosed for testing tensile strength of microfilaments. Fibers as small as 0.001 inch in diameter and 0.04 inches in length have been tested, although the method and apparatus of the invention are capable of testing fibers of smaller diameter and length. The invention utilizes a method wherein one or both ends of a microfilament is gripped using resin which is softened sufficiently to accept an end of the microfilament and then allowed to harden. The invention also employs the use of a translation stage capable of controlled three-dimensional movement suited to facilitating gripping of the microfilament. 2 figs.

  4. Continuous plutonium dissolution apparatus

    DOEpatents

    Meyer, F.G.; Tesitor, C.N.

    1974-02-26

    This invention is concerned with continuous dissolution of metals such as plutonium. A high normality acid mixture is fed into a boiler vessel, vaporized, and subsequently condensed as a low normality acid mixture. The mixture is then conveyed to a dissolution vessel and contacted with the plutonium metal to dissolve the plutonium in the dissolution vessel, reacting therewith forming plutonium nitrate. The reaction products are then conveyed to the mixing vessel and maintained soluble by the high normality acid, with separation and removal of the desired constituent. (Official Gazette)

  5. Synthesis and characterization of [BMIM]bromide using microwave-assisted organic synthesis method and its application for dissolution of palm empty fruit bunch

    SciTech Connect

    Arianie, Lucy; Wahyuningrum, Deana Nurrachman, Zeily Natalia, Dessy

    2014-03-24

    The decrease of cellulose crystallinity index of palm empty fruit bunch is crucial for the next application of cellulose as raw material for various biofuel and its derivatives. The aim of this research is to decrease the cellulose crystallinity index of palm empty fruit bunch using 1-butyl-3-methylimidazoliumbromide or [BMIM] bromide which has been synthesized using Microwave-Assisted Organic Synthesis (MAOS) method. Conventional reaction method has also been carried out to synthesize [BMIM]bromide for comparison as well. The characterization of synthesized product using FTIR, {sup 1}H-NMR, {sup 13}C-NMR and LC-MS showed that these reactions have been carried out successfully. The results showed that MAOS method is up to 90% faster in producing [BMIM]bromide compare to the conventional method. The application of [BMIM]bromide for dissolution of palm empty fruit bunch showed that cellulose and lignin could be extracted using stirring process for 20 hours. The decrease of cellulose crystallinity index and its morphology changes were identified using FTIR and Scanning Electron Microscope.

  6. In vitro Dissolution Studies on Solid Dispersions of Mefenamic Acid

    PubMed Central

    Rao, K. R. S. Sambasiva; Nagabhushanam, M V; Chowdary, K. P. R.

    2011-01-01

    Solid dispersions of mefanamic acid with a water-soluble polymer polyvinyl pyrrolidine and a super disintegrant, primojel were prepared by common solvent and solvent evaporation methods employing methanol as the solvent. The dissolution rate and dissolution efficiency of the prepared solid dispersions were evaluated in comparison to the corresponding pure drug. Solid dispersions of mefenamic acid showed a marked enhancement in dissolution rate and dissolution efficiency. At 1:4 ratio of mefenamic acid-primojel a 2.61 fold increase in the dissolution rate of mefenamic acid was observed with solid dispersion. The solid dispersions in combined carriers gave much higher rates of dissolution than super disintegrants alone. Mefanamic acid-primojel-polyvinyl pyrrolidine (1:3.2:0.8) solid dispersion gave a 4.11 fold increase in the dissolution rate of mefenamic acid. Super disintegrants alone or in combination with polyvinyl pyrrolidine could be used to enhance the dissolution rate of mefenamic acid. PMID:22303074

  7. Chlorhexidine gel associated with papain in pulp tissue dissolution

    PubMed Central

    Couto De Oliveira, Gabriel; Ferraz, Caio Souza; Andrade Júnior, Carlos Vieira

    2013-01-01

    Objectives This study aimed to evaluate the capacity of 2% chlorhexidine gel associated with 8% papain gel in comparison with 5.25% sodium hypochlorite in bovine pulp tissue dissolution. Materials and Methods Ninety bovine pulps of standardized sizes were used and fragmented into 5-mm sizes. The fragments were removed from the root middle third region. They were divided into 6 experimental groups (n = 15), 1) 8% papain; 2) 2% chlorhexidine; 3) 2% chlorhexidine associated with 8% papain; 4) 0.9% saline solution; 5) 2.5% sodium hypochlorite; and 6) 5.25% sodium hypochlorite. The pulp fragments were weighed and put into immobile test tubes for dissolution for time intervals of 30, 60, 90, and 120 min. Results The 5.25% sodium hypochlorite had greater dissolution potential than the pure papain, and when associated with chlorhexidine, both promoted greater dissolution than did the saline solution and 2% chlorhexidine groups (p < 0.05). The 2.5% sodium hypochlorite promoted dissolution to a lesser extent than the groups with papain within a period of 30 min (p < 0.05), but, was comparable to the saline solution and chlorhexidine. After 120 min, the 2.5% and 5.25% sodium hypochlorite promoted dissolution of 100% of the pulp fragments, and papain, 61%, while chlorhexidine associated with papain and chlorhexidine alone dissolved only 55% and 3%, respectively. Conclusions The 8% papain in gel, both alone and in association with chlorhexidine, was able to dissolve bovine pulp tissue, but to a lesser extent than did 5.25% sodium hypochlorite. PMID:24303355

  8. The chronic toxicity of ZnO nanoparticles and ZnCl2 to Daphnia magna and the use of different methods to assess nanoparticle aggregation and dissolution.

    PubMed

    Adam, Nathalie; Schmitt, Claudia; Galceran, Josep; Companys, Encarna; Vakurov, Alexander; Wallace, Rachel; Knapen, Dries; Blust, Ronny

    2014-11-01

    In this study, the effect of ZnO nanoparticles and ZnCl2 on growth, reproduction and accumulation of zinc in Daphnia magna was determined in a 21-day chronic toxicity test. A variety of techniques were used to distinguish the free zinc ion, dissolved, nanoparticle and aggregated zinc fraction in the Daphnia test medium. The results showed similar chronic effects on growth, reproduction and accumulation for the ZnO nanoparticles (EC10, 20, 50 reproduction: 0.030, 0.049, 0.112 mg Zn/l) and the ZnCl2 (EC10, 20, 50 reproduction: 0.014, 0.027, 0.082 mg Zn/l). A large fraction of the nanoparticles rapidly dissolved after introduction in the exposure medium. Aggregation of nanoparticles was also observed but within 48 h of exposure most of these ZnO aggregates were dissolved. Based on the combined dissolution kinetics and toxicity results, it can be concluded that the toxicological effects of ZnO nanoparticles at the chronic level can be largely attributed to the dissolved fraction rather than the nanoparticles or initially formed aggregates.

  9. The dilemma of disappearing diatoms: Incorporating diatom dissolution data into palaeoenvironmental modelling and reconstruction

    NASA Astrophysics Data System (ADS)

    Ryves, David B.; Battarbee, Richard W.; Fritz, Sherilyn C.

    2009-01-01

    Taphonomic issues pose fundamental challenges for Quaternary scientists to recover environmental signals from biological proxies and make accurate inferences of past environments. The problem of microfossil preservation, specifically diatom dissolution, remains an important, but often overlooked, source of error in both qualitative and quantitative reconstructions of key variables from fossil samples, especially those using relative abundance data. A first step to tackling this complex issue is establishing an objective method of assessing preservation (here, diatom dissolution) that can be applied by different analysts and incorporated into routine counting strategies. Here, we establish a methodology for assessment of diatom dissolution under standard light microscopy (LM) illustrated with morphological criteria for a range of major diatom valve shapes. Dissolution data can be applied to numerical models (transfer functions) from contemporary samples, and to fossil material to aid interpretation of stratigraphic profiles and taphonomic pathways of individual taxa. Using a surface sediment diatom-salinity training set from the Northern Great Plains (NGP) as an example, we explore a variety of approaches to include dissolution data in salinity inference models indirectly and directly. Results show that dissolution data can improve models, with apparent dissolution-adjusted error (RMSE) up to 15% lower than their unadjusted counterparts. Internal validation suggests improvements are more modest, with bootstrapped prediction errors (RMSEP) up to 10% lower. When tested on a short core from Devils Lake, North Dakota, which has a historical record of salinity, dissolution-adjusted models infer higher values compared to unadjusted models during peak salinity of the 1930s-1940s Dust Bowl but nonetheless significantly underestimate peak values. Site-specific factors at Devils Lake associated with effects of lake level change on taphonomy (preservation and re

  10. In silico dissolution rates of pharmaceutical ingredients

    NASA Astrophysics Data System (ADS)

    Dogan, Berna; Schneider, Julian; Reuter, Karsten

    2016-10-01

    The correlation between in vitro dissolution rates and the efficiency of drug formulations establishes an opportunity for accelerated drug development. Using in silico methods to predict the dissolution rates bears the prospect of further efficiency gains by avoiding the actual synthesis of candidate formulations. Here, we present a computational protocol that achieves such prediction for molecular crystals at low undersaturation. The protocol exploits the classic spiral dissolution model to minimize the number of material parameters that require explicit molecular simulations. Comparison to available data for acetylsalicylic acid and alpha lactose monohydrate indicates a tunable accuracy within one order of magnitude.

  11. A comparison of test methods for determining in vitro drug release from transdermal delivery dosage forms.

    PubMed

    Mazzo, D J; Fong, E K; Biffar, S E

    1986-01-01

    Three test methods for determining in vitro drug release rate from transdermal delivery dosage forms were tested for equivalency of results, ease of implementation and precision. The 'paddle-over-disk' (POD) method is under consideration by the USP as a standarized method for release-rate testing of all transdermal delivery dosage forms. The 'reciprocating disk' (RD) and 'diffusion cell' (DC) methods are both commonly employed throughout the pharmaceutical industry. The three methods were demonstrated to be equivalent in terms of release rate profile (curve shape) and total drug released over the lifetime of the dosage form tested (Transderm-Scop). The precision for the RD method as measured by the mean relative standard deviation over all time points was 4.6%; the precision of the POD method was 5.4% and that for the DC method was 6.7%. Steady-state flux values derived from the POD and RD methods were equivalent ( approximately 4 microg cm(-2) h(-1)) but were approximately 25% greater than the steady-state flux value derived from the DC method ( approximately 3 microg cm(-2) h(-1)). All three methods gave results which were within the specifications of the manufacturer (CIBA-GEIGY). The POD method was the easiest to use on a routine basis, required the least amount of specialized equipment and most resembled the current test methodology for dissolution testing of other dosage forms such as tablets or capsules.

  12. Alternative Test Methods for Electronic Parts

    NASA Technical Reports Server (NTRS)

    Plante, Jeannette

    2004-01-01

    It is common practice within NASA to test electronic parts at the manufacturing lot level to demonstrate, statistically, that parts from the lot tested will not fail in service using generic application conditions. The test methods and the generic application conditions used have been developed over the years through cooperation between NASA, DoD, and industry in order to establish a common set of standard practices. These common practices, found in MIL-STD-883, MIL-STD-750, military part specifications, EEE-INST-002, and other guidelines are preferred because they are considered to be effective and repeatable and their results are usually straightforward to interpret. These practices can sometimes be unavailable to some NASA projects due to special application conditions that must be addressed, such as schedule constraints, cost constraints, logistical constraints, or advances in the technology that make the historical standards an inappropriate choice for establishing part performance and reliability. Alternate methods have begun to emerge and to be used by NASA programs to test parts individually or as part of a system, especially when standard lot tests cannot be applied. Four alternate screening methods will be discussed in this paper: Highly accelerated life test (HALT), forward voltage drop tests for evaluating wire-bond integrity, burn-in options during or after highly accelerated stress test (HAST), and board-level qualification.

  13. ASTM Validates Air Pollution Test Methods

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    The American Society for Testing and Materials (ASTM) has validated six basic methods for measuring pollutants in ambient air as the first part of its Project Threshold. Aim of the project is to establish nationwide consistency in measuring pollutants; determining precision, accuracy and reproducibility of 35 standard measuring methods. (BL)

  14. Formal methods for test case generation

    NASA Technical Reports Server (NTRS)

    Rushby, John (Inventor); De Moura, Leonardo Mendonga (Inventor); Hamon, Gregoire (Inventor)

    2011-01-01

    The invention relates to the use of model checkers to generate efficient test sets for hardware and software systems. The method provides for extending existing tests to reach new coverage targets; searching *to* some or all of the uncovered targets in parallel; searching in parallel *from* some or all of the states reached in previous tests; and slicing the model relative to the current set of coverage targets. The invention provides efficient test case generation and test set formation. Deep regions of the state space can be reached within allotted time and memory. The approach has been applied to use of the model checkers of SRI's SAL system and to model-based designs developed in Stateflow. Stateflow models achieving complete state and transition coverage in a single test case are reported.

  15. Standard Test Methods for Textile Composites

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Portanova, Marc A.

    1996-01-01

    Standard testing methods for composite laminates reinforced with continuous networks of braided, woven, or stitched fibers have been evaluated. The microstructure of these textile' composite materials differs significantly from that of tape laminates. Consequently, specimen dimensions and loading methods developed for tape type composites may not be applicable to textile composites. To this end, a series of evaluations were made comparing testing practices currently used in the composite industry. Information was gathered from a variety of sources and analyzed to establish a series of recommended test methods for textile composites. The current practices established for laminated composite materials by ASTM and the MIL-HDBK-17 Committee were considered. This document provides recommended test methods for determining both in-plane and out-of-plane properties. Specifically, test methods are suggested for: unnotched tension and compression; open and filled hole tension; open hole compression; bolt bearing; and interlaminar tension. A detailed description of the material architectures evaluated is also provided, as is a recommended instrumentation practice.

  16. Prediction of dissolution profiles by non-destructive near infrared spectroscopy in tablets subjected to different levels of strain.

    PubMed

    Hernandez, Eduardo; Pawar, Pallavi; Keyvan, Golshid; Wang, Yifan; Velez, Natasha; Callegari, Gerardo; Cuitino, Alberto; Michniak-Kohn, Bozena; Muzzio, Fernando J; Romañach, Rodolfo J

    2016-01-01

    This study describes how the strain on formulation components affects dissolution and how near infrared spectroscopy can be used to predict dissolution. Strain (exposure to shear stress) applied during powder mixing affects the interaction between formulation components. Particles experience shear strain when they move relative to each other in a process affecting the properties of the final product. This stress affects the dissolution of oral solid dosages forms. However, dissolution testing destroys the entire tablet, making it impossible to further evaluate tablet properties when an out of specification result is obtained. Thus, a nondestructive technique such as near infrared spectroscopy is desirable to predict dissolution. The aim of this study was to predict dissolution on tablets with different levels of strain (shear) using near infrared spectroscopy in combination with multivariate data analysis. Shear was induced using a modified Couette cell on the powder mixture and tablets from these mixtures were produced using a tablet press emulator. Tablets produced with different strain levels were measured using near infrared spectroscopy. Spectra were obtained in diffuse reflectance mode and pretreated with baseline correction to maintain the physical and chemical information of the tablets. Dissolution profiles were obtained using USP Apparatus 2 as a reference method. Principal component analysis was used to study the sources of variation in the spectra obtained. Partial least squares 2 was used to predict dissolution on tablets with different levels of strain.

  17. Development of test methods for textile composites

    NASA Technical Reports Server (NTRS)

    Masters, John E.; Ifju, Peter G.; Fedro, Mark J.

    1993-01-01

    NASA's Advanced Composite Technology (ACT) Program was initiated in 1990 with the purpose of developing less costly composite aircraft structures. A number of innovative materials and processes were evaluated as a part of this effort. Chief among them are composite materials reinforced with textile preforms. These new forms of composite materials bring with them potential testing problems. Methods currently in practice were developed over the years for composite materials made from prepreg tape or simple 2-D woven fabrics. A wide variety of 2-D and 3-D braided, woven, stitched, and knit preforms were suggested for application in the ACT program. The applicability of existing test methods to the wide range of emerging materials bears investigation. The overriding concern is that the values measured are accurate representations of the true material response. The ultimate objective of this work is to establish a set of test methods to evaluate the textile composites developed for the ACT Program.

  18. Aflatoxin plate kit. Performance Tested Method 081003.

    PubMed

    Trombley, Arthur; Fan, Titan; LaBudde, Robert

    2011-01-01

    The level of total aflatoxin contamination was analyzed in naturally contaminated and spiked samples of corn and peanut using the Aflatoxin Plate Kit. This kit is an enzyme-linked immunosorbent assay (ELISA) suitable for rapid testing of grains and peanuts. The assay was evaluated for ruggedness and linearity of the standard curve. The test kit results were then statistically evaluated for accuracy, precision, and correlation to a validated HPLC method (AOAC 994.08). The results were verified by an independent laboratory.

  19. In-vitro bioactivity, biocompatibility and dissolution studies of diopside prepared from biowaste by using sol-gel combustion method.

    PubMed

    Choudhary, Rajan; Vecstaudza, Jana; Krishnamurithy, G; Raghavendran, Hanumantha Rao Balaji; Murali, Malliga Raman; Kamarul, Tunku; Swamiappan, Sasikumar; Locs, Janis

    2016-11-01

    Diopside was synthesized from biowaste (Eggshell) by sol-gel combustion method at low calcination temperature and the influence of two different fuels (urea, l-alanine) on the phase formation temperature, physical and biological properties of the resultant diopside was studied. The synthesized materials were characterized by heating microscopy, FTIR, XRD, BET, SEM and EDAX techniques. BET analysis reveals particles were of submicron size with porosity in the nanometer range. Bone-like apatite deposition ability of diopside scaffolds was examined under static and circulation mode of SBF (Simulated Body Fluid). It was noticed that diopside has the capability to deposit HAP (hydroxyapatite) within the early stages of immersion. ICP-OES analysis indicates release of Ca, Mg, Si ions and removal of P ions from the SBF, but in different quantities from diopside scaffolds. Cytocompatability studies on human bone marrow stromal cells (hBMSCs) revealed good cellular attachment on the surface of diopside scaffolds and formation of extracellular matrix (ECM). This study suggests that the usage of eggshell biowaste as calcium source provides an effective substitute for synthetic starting materials to fabricate bioproducts for biomedical applications. PMID:27524000

  20. Comparing various techniques to produce micro/nanoparticles for enhancing the dissolution of celecoxib containing PVP.

    PubMed

    Homayouni, Alireza; Sadeghi, Fatemeh; Varshosaz, Jaleh; Garekani, Hadi Afrasiabi; Nokhodchi, Ali

    2014-09-01

    One of the major challenges in pharmaceutical development is the poor dissolution performance of drugs. Celecoxib (CLX) is a poorly water soluble drug with its bioavailability being limited by its poor dissolution. In this study several particle engineering methods were employed on CLX using various ratios of CLX:PVP-K30. Micro/nanoparticles of CLX:PVP were prepared by using spray drying (SD), antisolvent crystallization followed by freeze drying (CRS-FD) and spray drying (CRS-SD) techniques. The suspension obtained through antisolvent crystallization was also subjected to high pressure homogenization followed by freeze drying (HPH-FD). Particle size measurements, saturation solubility, optical and scanning electron microscopy, DSC, XRPD, FT-IR and dissolution test were performed to characterize the physicochemical and pharmaceutical properties of the samples. The results showed that spray dried samples in the presence of (50%) PVP produced spherical particles and exhibited a high dissolution rate. Interestingly in the antisolvent crystallization technique, spherical nanoparticles of drug-PVP were obtained in the range of 291-442 nm. The average particle size was dependent on the concentration of the PVP used during the crystallization process. Solid state analysis showed that these particles were completely amorphous in nature. Also interesting to note was that at concentration of 5% PVP, when the suspension of nanoparticles was subjected to the high pressure homogenization process, the crystallinity of CLX increased. Despite the partial crystallinity of particles produced, they showed excellent dissolution behavior. It can thus be concluded that the method of preparation of CLX micro/nanoparticles had a big impact on the dissolution rate when the concentration of PVP was low (e.g., 5%). At high PVP concentration (e.g., 50%) all methods used to prepare engineered CLX particles showed better dissolution with no significant differences in their dissolution

  1. Integrating Formal Methods and Testing 2002

    NASA Technical Reports Server (NTRS)

    Cukic, Bojan

    2002-01-01

    Traditionally, qualitative program verification methodologies and program testing are studied in separate research communities. None of them alone is powerful and practical enough to provide sufficient confidence in ultra-high reliability assessment when used exclusively. Significant advances can be made by accounting not only tho formal verification and program testing. but also the impact of many other standard V&V techniques, in a unified software reliability assessment framework. The first year of this research resulted in the statistical framework that, given the assumptions on the success of the qualitative V&V and QA procedures, significantly reduces the amount of testing needed to confidently assess reliability at so-called high and ultra-high levels (10-4 or higher). The coming years shall address the methodologies to realistically estimate the impacts of various V&V techniques to system reliability and include the impact of operational risk to reliability assessment. Combine formal correctness verification, process and product metrics, and other standard qualitative software assurance methods with statistical testing with the aim of gaining higher confidence in software reliability assessment for high-assurance applications. B) Quantify the impact of these methods on software reliability. C) Demonstrate that accounting for the effectiveness of these methods reduces the number of tests needed to attain certain confidence level. D) Quantify and justify the reliability estimate for systems developed using various methods.

  2. Transport Test Problems for Hybrid Methods Development

    SciTech Connect

    Shaver, Mark W.; Miller, Erin A.; Wittman, Richard S.; McDonald, Benjamin S.

    2011-12-28

    This report presents 9 test problems to guide testing and development of hybrid calculations for the ADVANTG code at ORNL. These test cases can be used for comparing different types of radiation transport calculations, as well as for guiding the development of variance reduction methods. Cases are drawn primarily from existing or previous calculations with a preference for cases which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22.

  3. Dimensionality reduction, and function approximation of poly(lactic-co-glycolic acid) micro- and nanoparticle dissolution rate.

    PubMed

    Ojha, Varun Kumar; Jackowski, Konrad; Abraham, Ajith; Snášel, Václav

    2015-01-01

    Prediction of poly(lactic-co-glycolic acid) (PLGA) micro- and nanoparticles' dissolution rates plays a significant role in pharmaceutical and medical industries. The prediction of PLGA dissolution rate is crucial for drug manufacturing. Therefore, a model that predicts the PLGA dissolution rate could be beneficial. PLGA dissolution is influenced by numerous factors (features), and counting the known features leads to a dataset with 300 features. This large number of features and high redundancy within the dataset makes the prediction task very difficult and inaccurate. In this study, dimensionality reduction techniques were applied in order to simplify the task and eliminate irrelevant and redundant features. A heterogeneous pool of several regression algorithms were independently tested and evaluated. In addition, several ensemble methods were tested in order to improve the accuracy of prediction. The empirical results revealed that the proposed evolutionary weighted ensemble method offered the lowest margin of error and significantly outperformed the individual algorithms and the other ensemble techniques.

  4. Methods to Test Visual Attention Online

    PubMed Central

    Yung, Amanda; Cardoso-Leite, Pedro; Dale, Gillian; Bavelier, Daphne; Green, C. Shawn

    2015-01-01

    Online data collection methods have particular appeal to behavioral scientists because they offer the promise of much larger and much more representative data samples than can typically be collected on college campuses. However, before such methods can be widely adopted, a number of technological challenges must be overcome – in particular in experiments where tight control over stimulus properties is necessary. Here we present methods for collecting performance data on two tests of visual attention. Both tests require control over the visual angle of the stimuli (which in turn requires knowledge of the viewing distance, monitor size, screen resolution, etc.) and the timing of the stimuli (as the tests involve either briefly flashed stimuli or stimuli that move at specific rates). Data collected on these tests from over 1700 online participants were consistent with data collected in laboratory-based versions of the exact same tests. These results suggest that with proper care, timing/stimulus size dependent tasks can be deployed in web-based settings. PMID:25741746

  5. [Process monitoring of dissolution of valsartan and hydrochlorothiazide tablets by fiber-chemical sensor assisted by mathematical separation model of linear equations].

    PubMed

    Ding, Hai-Yan; Li, Gai-Ru; Yu, Ying-Ge; Guo, Wei; Zhi, Ling; Li, Xin-Xia

    2014-04-01

    A method for on-line monitoring the dissolution of Valsartan and hydrochlorothiazide tablets assisted by mathematical separation model of linear equations was established. UV spectrums of valsartan and hydrochlorothiazide were overlapping completely at the maximum absorption wavelength respectively. According to the Beer-Lambert principle of absorbance additivity, the absorptivity of Valsartan and hydrochlorothiazide was determined at the maximum absorption wavelength, and the dissolubility of Valsartan and hydrochlorothiazide tablets was detected by fiber-optic dissolution test (FODT) assisted by the mathematical separation model of linear equations and compared with the HPLC method. Results show that two ingredients were real-time determined simultaneously in given medium. There was no significant difference for FODT compared with HPLC (p > 0.05). Due to the dissolution behavior consistency, the preparation process of different batches was stable and with good uniformity. The dissolution curves of valsartan were faster and higher than hydrochlorothiazide. The dissolutions at 30 min of Valsartan and hydrochlorothiazide were concordant with US Pharmacopoeia. It was concluded that fiber-optic dissolution test system assisted by the mathematical separation model of linear equations that can detect the dissolubility of Valsartan and hydrochlorothiazide simultaneously, and get dissolution profiles and overall data, which can directly reflect the dissolution speed at each time. It can provide the basis for establishing standards of the drug. Compared to HPLC method with one-point data, there are obvious advantages to evaluate and analyze quality of sampling drug by FODT. PMID:25007628

  6. Method for non-destructive testing

    DOEpatents

    Akers, Douglas W.

    2011-08-30

    Non-destructive testing method may include providing a source material that emits positrons in response to bombardment of the source material with photons. The source material is exposed to photons. The source material is positioned adjacent the specimen, the specimen being exposed to at least some of the positrons emitted by the source material. Annihilation gamma rays emitted by the specimen are detected.

  7. IMPROVED TEST METHODS FOR ELECTRONIC AIR CLEANERS

    EPA Science Inventory

    The objective of this project was to develop a fractional filtration efficiency test protocol for residential electrostatic precipitators (ESPs) that avoids the limitations of the ASHRAE 52.2 method. Specifically, the objectives were to a) determine the change in efficiency that ...

  8. Equated Pooled Booklet Method in DIF Testing

    ERIC Educational Resources Information Center

    Cheng, Ying; Chen, Peihua; Qian, Jiahe; Chang, Hua-Hua

    2013-01-01

    Differential item functioning (DIF) analysis is an important step in the data analysis of large-scale testing programs. Nowadays, many such programs endorse matrix sampling designs to reduce the load on examinees, such as the balanced incomplete block (BIB) design. These designs pose challenges to the traditional DIF analysis methods. For example,…

  9. 16 CFR 1213.4 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... STANDARD FOR ENTRAPMENT HAZARDS IN BUNK BEDS § 1213.4 Test methods. (a) Guardrails (see § 1213.3(a)(6)). With no mattress on the bed, place the wedge block shown in Figure 1, tapered side first, into each opening in the bed structure below the lower edge of the uppermost member of the guardrail and above...

  10. 16 CFR 1513.4 - Test methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REQUIREMENTS FOR BUNK BEDS § 1513.4 Test methods. (a) Guardrails (see § 1513.3(a)(6)). With no mattress on the bed, place the wedge block shown in Figure 1, tapered side first, into each opening in the rigid...

  11. Testing alleged mediumship: methods and results.

    PubMed

    O'keeffe, Ciarán; Wiseman, Richard

    2005-05-01

    Mediums claim to be able to communicate with the deceased. Such claims attract a considerable amount of public interest and, if valid, have important implications for many areas of psychology. For over 100 years, researchers have tested alleged mediums. This work has obtained mixed results and provoked a considerable amount of methodological debate. This paper reviews the key issues in this debate, describes how the authors devised a method of testing that aimed to prevent the many problems that have hindered past research, and how they then used this method to test several professional mediums. The results of this work did not support the existence of genuine mediumistic ability. Competing interpretations of these results are discussed, along with ways in which the methodology presented in the paper could be used to assess conceptually similar, but non-paranormal, claims made in clinical, occupational and forensic contexts.

  12. Unemployment and marital dissolution.

    PubMed

    Jensen, P; Smith, N

    1990-01-01

    "This paper analyses the effects of unemployment on the probability of marital dissolution. Based on panel data for a sample of Danish married couples, we estimate a dynamic model for the probability of marital dissolution where we take into account the possible effects of unemployment for both spouses. We also control for other factors such as education, age, presence of children, place of residence, health and economic factors. The empirical results show that unemployment seems to be an important factor behind marital instability. However, only unemployment of the husband has an effect, and this effect is immediate." PMID:12283481

  13. High temperature pressurized high frequency testing rig and test method

    DOEpatents

    De La Cruz, Jose; Lacey, Paul

    2003-04-15

    An apparatus is described which permits the lubricity of fuel compositions at or near temperatures and pressures experienced by compression ignition fuel injector components during operation in a running engine. The apparatus consists of means to apply a measured force between two surfaces and oscillate them at high frequency while wetted with a sample of the fuel composition heated to an operator selected temperature. Provision is made to permit operation at or near the flash point of the fuel compositions. Additionally a method of using the subject apparatus to simulate ASTM Testing Method D6079 is disclosed, said method involving using the disclosed apparatus to contact the faces of prepared workpieces under a measured load, sealing the workface contact point into the disclosed apparatus while immersing said contact point between said workfaces in a lubricating media to be tested, pressurizing and heating the chamber and thereby the fluid and workfaces therewithin, using the disclosed apparatus to impart a differential linear motion between the workpieces at their contact point until a measurable scar is imparted to at least one workpiece workface, and then evaluating the workface scar.

  14. Enhanced dissolution and stability of Tanshinone IIA base by solid dispersion system with nano-hydroxyapatite

    PubMed Central

    Jiang, Yan-rong; Zhang, Zhen-hai; Huang, Sai-yan; Lu, Yan; Ma, Tian-tian; Jia, Xiao-bin

    2014-01-01

    Background: Tanshinone IIA (TSIIA) exhibits a variety of cardiovascular effects; however, it has low solubility in water. The preparation of poorly soluble drugs for oral delivery is one of the greatest challenges in the field of formulation research. Among the approaches available, solid dispersion (SD) technique has proven to be one of the most commonly used these methods for improving dissolution and bioavailability of drugs, because of its relative simplicity and economy in terms of both preparation and evaluation. Objective: This study was aimed at investigating the dissolution behavior and physical stability of SDs of TSIIA by employing nano-hydroxyapatite (n-HAp). Materials and Methods: The TSIIA SDs was prepared to use a spray-drying method. First, an in vitro dissolution test was performed to assess dissolution characteristics. Next, a set of complementary techniques (differential scanning calorimetry, scanning electron microscopy, X-ray powder diffraction, and Fourier transform infrared spectroscopy) was used to monitor the physicochemical properties of the SDs. The SDs was stored at 40°C/75% relative humidity for 6 months, after which their stability was assessed. Results: TSIIA dissolution remarkably improved because of the formulation of the SDs with n-HAp particles. Comparisons with the corresponding physical mixtures revealed changes in the SDs and explained the formation of the amorphous phase. In the stability test, virtually no time-dependent decrease was observed in either in vitro drug dissolution or drug content. Conclusion: SD formulation with n-HAp may be a promising approach for enhancing the dissolution and stability of TSIIA. PMID:25210322

  15. Mergers, Annexations, Dissolutions

    ERIC Educational Resources Information Center

    Russo, Alexander

    2006-01-01

    Consolidations come in all shapes and sizes, including mergers, annexations and dissolutions. They do not all take place under state mandate, however. A handful of districts consolidate every year in some states like Illinois that have large numbers of small districts, many of them dual districts that serve K-8 or 9-12 in the same geographic area.…

  16. Methods and instruments for materials testing

    NASA Technical Reports Server (NTRS)

    Hansma, Paul (Inventor); Drake, Barney (Inventor); Rehn, Douglas (Inventor); Adams, Jonathan (Inventor); Lulejian, Jason (Inventor)

    2011-01-01

    Methods and instruments for characterizing a material, such as the properties of bone in a living human subject, using a test probe constructed for insertion into the material and a reference probe aligned with the test probe in a housing. The housing is hand held or placed so that the reference probe contacts the surface of the material under pressure applied either by hand or by the weight of the housing. The test probe is inserted into the material to indent the material while maintaining the reference probe substantially under the hand pressure or weight of the housing allowing evaluation of a property of the material related to indentation of the material by the probe. Force can be generated by a voice coil in a magnet structure to the end of which the test probe is connected and supported in the magnet structure by a flexure, opposing flexures, a linear translation stage, or a linear bearing. Optionally, a measurement unit containing the test probe and reference probe is connected to a base unit with a wireless connection, allowing in the field material testing.

  17. Interpretation and optimization of the dissolution specifications for a modified release product with an in vivo-in vitro correlation (IVIVC).

    PubMed

    Hayes, Siobhán; Dunne, Adrian; Smart, Trevor; Davis, John

    2004-03-01

    This article considers the in vivo significance attached to in vitro dissolution testing. Almost invariably, the in vitro dissolution test is interpreted in terms of bioequivalence. The literature that describes methods for setting in vitro dissolution specifications is reviewed. The most common interpretation of these specifications is a deterministic one, that is, those batches passing the dissolution specifications would be bioequivalent with the reference if tested in vivo and those failing the dissolution specifications would not be bioequivalent if tested in vivo. Due to random variation, the deterministic interpretation is not appropriate. Instead, we need to consider the conditional probability that a batch that has passed the in vitro dissolution test would demonstrate bioequivalence if tested in vivo, and that a batch known to have failed the in vitro dissolution test would demonstrate bioinequivalence if tested in vivo. One way to estimate these probabilities is by means of a simulated experiment in which the production and testing (in vivo and in vitro) of a large number of batches is computer simulated. Such a simulation can only be performed if the relationship between the in vitro dissolution characteristics and the in vivo performance of the product has been modeled. These models are generally referred to as in vivo-in vitro correlations (IVIVC). The results of one such experiment are described. The above-mentioned conditional probabilities are shown to depend on the choice of dissolution specifications. This result leads to the notion of optimal dissolution specifications. However, both of the conditional probabilities cannot be maximized simultaneously. The probability of making a correct decision on the basis of the in vitro dissolution test is introduced as a possible optimality criterion. This probability is a linear combination of the two conditional probabilities of interest. Using this criterion, the optimal dissolution specifications can be

  18. Singlepath Salmonella. Performance Tested Method 060401.

    PubMed

    Lindhardt, Charlotte; Schönenbrücher, Holger; Slaghuis, Jörg; Bubert, Andreas; Ossmer, Rolf

    2009-01-01

    Singlepath Salmonella is an immunochromatographic (lateral flow) assay for the presumptive qualitative detection of Salmonella spp. in food. A previous AOAC Performance Tested Method study evaluated Singlepath Salmonella as an effective method for the detection of Salmonella spp. in the following selected foods: dried skimmed milk, black pepper, dried pet food, desiccated coconut, cooked peeled frozen prawns, raw ground beef, and raw ground turkey. In this Emergency Response Validation extension, creamy peanut butter was inoculated with S. enterica. ser. Typhimurium. For low contamination level (1.08 CFU/25 g), a Chi-square value of 0.5 indicated that there was no significant difference between Singlepath Salmonella and the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) reference method. For high-level and uninoculated control there was 100% agreement between the methods. PMID:20166612

  19. Explosive materials equivalency, test methods and evaluation

    NASA Technical Reports Server (NTRS)

    Koger, D. M.; Mcintyre, F. L.

    1980-01-01

    Attention is given to concepts of explosive equivalency of energetic materials based on specific airblast parameters. A description is provided of a wide bandwidth high accuracy instrumentation system which has been used extensively in obtaining pressure time profiles of energetic materials. The object of the considered test method is to determine the maximum output from the detonation of explosive materials in terms of airblast overpressure and positive impulse. The measured pressure and impulse values are compared with known characteristics of hemispherical TNT data to determine the equivalency of the test material in relation to TNT. An investigation shows that meaningful comparisons between various explosives and a standard reference material such as TNT should be based upon the same parameters. The tests should be conducted under the same conditions.

  20. Characterization methods for ultrasonic test systems

    SciTech Connect

    Busse, L.J.; Becker, F.L.; Bowey, R.E.; Doctor, S.R.; Gribble, R.P.; Posakony, G.J.

    1982-07-01

    Methods for the characterization of ultrasonic transducers (search units) and instruments are presented. The instrument system is considered as three separate components consisting of a transducer, a receiver-display, and a pulser. The operation of each component is assessed independently. The methods presented were chosen because they provide the greatest amount of information about component operation and were not chosen based upon such conditions as cost, ease of operation, field implementation, etc. The results of evaluating a number of commercially available ultrasonic test instruments are presented.

  1. Calcination/dissolution residue treatment

    SciTech Connect

    Knight, R.C.; Creed, R.F.; Patello, G.K.; Hollenberg, G.W.; Buehler, M.F.; O`Rourke, S.M.; Visnapuu, A.; McLaughlin, D.F.

    1994-09-01

    Currently, high-level wastes are stored underground in steel-lined tanks at the Hanford site. Current plans call for the chemical pretreatment of these wastes before their immobilization in stable glass waste forms. One candidate pretreatment approach, calcination/dissolution, performs an alkaline fusion of the waste and creates a high-level/low-level partition based on the aqueous solubilities of the components of the product calcine. Literature and laboratory studies were conducted with the goal of finding a residue treatment technology that would decrease the quantity of high-level waste glass required following calcination/dissolution waste processing. Four elements, Fe, Ni, Bi, and U, postulated to be present in the high-level residue fraction were identified as being key to the quantity of high-level glass formed. Laboratory tests of the candidate technologies with simulant high-level residues showed reductive roasting followed by carbonyl volatilization to be successful in removing Fe, Ni, and Bi. Subsequent bench-scale tests on residues from calcination/dissolution processing of genuine Hanford Site tank waste showed Fe was separated with radioelement decontamination factors of 70 to 1,000 times with respect to total alpha activity. Thermodynamic analyses of the calcination of five typical Hanford Site tank waste compositions also were performed. The analyses showed sodium hydroxide to be the sole molten component in the waste calcine and emphasized the requirement for waste blending if fluid calcines are to be achieved. Other calcine phases identified in the thermodynamic analysis indicate the significant thermal reconstitution accomplished in calcination.

  2. Crystal growth of calcite from calcium bicarbonate solutions at constant PCO2 and 25°C: a test of a calcite dissolution model

    USGS Publications Warehouse

    Reddy, Michael M.; Plummer, L. Neil; Busenberg, E.

    1981-01-01

    A highly reproducible seeded growth technique was used to study calcite crystallization from calcium bicarbonate solutions at 25°C and fixed carbon dioxide partial pressures between 0.03 and 0.3 atm. The results are not consistent with empirical crystallization models that have successfully described calcite growth at low PCO2 (< 10−3 atm). Good agreement was found between observed crystallization rates and those calculated from the calcite dissolution rate law and mechanism proposed by Plummer et al. (1978).

  3. Control system health test system and method

    DOEpatents

    Hoff, Brian D.; Johnson, Kris W.; Akasam, Sivaprasad; Baker, Thomas M.

    2006-08-15

    A method is provided for testing multiple elements of a work machine, including a control system, a component, a sub-component that is influenced by operations of the component, and a sensor that monitors a characteristic of the sub-component. In one embodiment, the method is performed by the control system and includes sending a command to the component to adjust a first parameter associated with an operation of the component. Also, the method includes detecting a sensor signal from the sensor reflecting a second parameter associated with a characteristic of the sub-component and determining whether the second parameter is acceptable based on the command. The control system may diagnose at least one of the elements of the work machine when the second parameter of the sub-component is not acceptable.

  4. Assessing Social Isolation: Pilot Testing Different Methods.

    PubMed

    Taylor, Harry Owen; Herbers, Stephanie; Talisman, Samuel; Morrow-Howell, Nancy

    2016-04-01

    Social isolation is a significant public health problem among many older adults; however, most of the empirical knowledge about isolation derives from community-based samples. There has been less attention given to isolation in senior housing communities. The objectives of this pilot study were to test two methods to identify socially isolated residents in low-income senior housing and compare findings about the extent of isolation from these two methods. The first method, self-report by residents, included 47 out of 135 residents who completed in-person interviews. To determine self-report isolation, residents completed the Lubben Social Network Scale 6 (LSNS-6). The second method involved a staff member who reported the extent of isolation on all 135 residents via an online survey. Results indicated that 26% of residents who were interviewed were deemed socially isolated by the LSNS-6. Staff members rated 12% of residents as having some or a lot of isolation. In comparing the two methods, staff members rated 2% of interviewed residents as having a lot of isolation. The combination of self-report and staff report could be more informative than just self-report alone, particularly when participation rates are low. However, researchers should be aware of the potential discrepancy between these two methods. PMID:27276687

  5. Assessing Social Isolation: Pilot Testing Different Methods.

    PubMed

    Taylor, Harry Owen; Herbers, Stephanie; Talisman, Samuel; Morrow-Howell, Nancy

    2016-04-01

    Social isolation is a significant public health problem among many older adults; however, most of the empirical knowledge about isolation derives from community-based samples. There has been less attention given to isolation in senior housing communities. The objectives of this pilot study were to test two methods to identify socially isolated residents in low-income senior housing and compare findings about the extent of isolation from these two methods. The first method, self-report by residents, included 47 out of 135 residents who completed in-person interviews. To determine self-report isolation, residents completed the Lubben Social Network Scale 6 (LSNS-6). The second method involved a staff member who reported the extent of isolation on all 135 residents via an online survey. Results indicated that 26% of residents who were interviewed were deemed socially isolated by the LSNS-6. Staff members rated 12% of residents as having some or a lot of isolation. In comparing the two methods, staff members rated 2% of interviewed residents as having a lot of isolation. The combination of self-report and staff report could be more informative than just self-report alone, particularly when participation rates are low. However, researchers should be aware of the potential discrepancy between these two methods.

  6. A new method of field MRTD test

    NASA Astrophysics Data System (ADS)

    Chen, Zhibin; Song, Yan; Liu, Xianhong; Xiao, Wenjian

    2014-09-01

    MRTD is an important indicator to measure the imaging performance of infrared camera. In the traditional laboratory test, blackbody is used as simulated heat source which is not only expensive and bulky but also difficult to meet field testing requirements of online automatic infrared camera MRTD. To solve this problem, this paper introduces a new detection device for MRTD, which uses LED as a simulation heat source and branded plated zinc sulfide glass carved four-bar target as a simulation target. By using high temperature adaptability cassegrain collimation system, the target is simulated to be distance-infinite so that it can be observed by the human eyes to complete the subjective test, or collected to complete objective measurement by image processing. This method will use LED to replace blackbody. The color temperature of LED is calibrated by thermal imager, thereby, the relation curve between the LED temperature controlling current and the blackbody simulation temperature difference is established, accurately achieved the temperature control of the infrared target. Experimental results show that the accuracy of the device in field testing of thermal imager MRTD can be limited within 0.1K, which greatly reduces the cost to meet the project requirements with a wide application value.

  7. Singlepath Salmonella. Performance-Tested Method 060401.

    PubMed

    Thompson, Lisa; Lindhardt, Charlotte

    2006-01-01

    Singlepath Salmonella is an immunochromatographic (lateral flow) assay for the presumptive qualitative detection of Salmonella spp. in food. The AOAC Performance-Tested Method study evaluated Singlepath Salmonella as an effective method for the detection of Salmonella spp. in the following selected foods: dried skimmed milk, black pepper, dried pet food, desiccated coconut, cooked peeled frozen prawns, raw ground beef, and raw ground turkey. When the foods were inoculated with Salmonella spp. at levels ranging from low [0.23-1.08 colony forming units (CFU)/25 g] to high (2.3-6.0 CFU/25 g), a Chi-square value of 0.9 indicated that there was no significant difference between Singlepath Salmonella and the ISO 6579:2002 reference method. Singlepath Salmonella gave a false-positive rate of 7.3% and a false-negative rate of 2.5%. For the inclusivity study, all 105 Salmonella serovars reacted with Singlepath Salmonella. For the exclusivity study, 58 non-Salmonella spp. were tested. There were no cross-reactions with Singlepath Salmonella from these strains. PMID:16640289

  8. Noise-abatement method for explosives testing.

    PubMed

    Pfeifer, H E; Odell, B N; Arganbright, V E

    1980-09-01

    When Lawrence Livermore Laboratory started detonating explosives at its Site 300 test location in the sparsely populated hills east of the Laboratory, residents in neighboring areas complained of sudden loud noises. A combined literature and research study, coupled with an experimental test program, indicated the combination of air temperatures and winds at various elevations was primarily responsible for blast or sound waves being returned to the surface. To solve the noise problem, the Laboratory devised a method for determining the maximum amount of explosives that could be detonated aboveground under various atmospheric conditions without creating excessive noise in populated areas. This method for predicting explosives weight limits using pressure-distance-weight nomograms and the slope of a sound-velocity curve is described in this paper. The sound-velocity curve is computed with temperature information from the U.S. Weather Bureau and wind data from a target-acquisition radar system. By following this method, the Laboratory has been able to detonate thousands of shots without creating excessive noise in nearby communities. PMID:7457390

  9. Experimental test of airplane boarding methods

    SciTech Connect

    Steffen, Jason H.; Hotchkiss, Jon

    2011-10-26

    We report the results of an experimental comparison of different airplane boarding methods. This test was conducted in a mock 757 fuselage, located on a Southern California soundstage, with 12 rows of six seats and a single aisle. Five methods were tested using 72 passengers of various ages. We found a significant reduction in the boarding times of optimized methods over traditional methods. These improved methods, if properly implemented, could result in a significant savings to airline companies. The process of boarding an airplane is of interest to a variety of groups. The public is interested both as a curiosity, as it is something that they may regularly experience, and as a consumer, as their experiences good or bad can affect their loyalties. Airline companies and their employees also have a stake in an efficient boarding procedure as time saved in the boarding process may result is monetary savings, in the quality of interactions with passengers, and in the application of human resources to the general process of preparing an airplane for departure. A recent study (Nyquist and McFadden, 2008) indicates that the average cost to an airline company for each minute of time spent at the terminal is roughly $30. Thus, each minute saved in the turn-around time of a flight has the potential to generate over $16,000,000 in annual savings (assuming an average of 1500 flights per day). While the boarding process may not be the primary source of delay in returning an airplane to the skies, reducing the boarding time may effectively eliminate passenger boarding as a contributor in any meaningful measure. Consequently, subsequent efforts to streamline the other necessary tasks, such as refueling and maintenance, would be rewarded with a material reduction in time at the gate for each flight.

  10. Experimental test of airplane boarding methods

    DOE PAGESBeta

    Steffen, Jason H.; Hotchkiss, Jon

    2011-10-26

    We report the results of an experimental comparison of different airplane boarding methods. This test was conducted in a mock 757 fuselage, located on a Southern California soundstage, with 12 rows of six seats and a single aisle. Five methods were tested using 72 passengers of various ages. We found a significant reduction in the boarding times of optimized methods over traditional methods. These improved methods, if properly implemented, could result in a significant savings to airline companies. The process of boarding an airplane is of interest to a variety of groups. The public is interested both as a curiosity,more » as it is something that they may regularly experience, and as a consumer, as their experiences good or bad can affect their loyalties. Airline companies and their employees also have a stake in an efficient boarding procedure as time saved in the boarding process may result is monetary savings, in the quality of interactions with passengers, and in the application of human resources to the general process of preparing an airplane for departure. A recent study (Nyquist and McFadden, 2008) indicates that the average cost to an airline company for each minute of time spent at the terminal is roughly $30. Thus, each minute saved in the turn-around time of a flight has the potential to generate over $16,000,000 in annual savings (assuming an average of 1500 flights per day). While the boarding process may not be the primary source of delay in returning an airplane to the skies, reducing the boarding time may effectively eliminate passenger boarding as a contributor in any meaningful measure. Consequently, subsequent efforts to streamline the other necessary tasks, such as refueling and maintenance, would be rewarded with a material reduction in time at the gate for each flight.« less

  11. Test versus analysis: A discussion of methods

    NASA Technical Reports Server (NTRS)

    Butler, T. G.

    1986-01-01

    Some techniques for comparing structural vibration data determined from test and analysis are discussed. Orthogonality is a general category of one group, correlation is a second, synthesis is a third and matrix improvement is a fourth. Advantages and short-comings of the methods are explored with suggestions as to how they can complement one another. The purpose for comparing vibration data from test and analysis for a given structure is to find out whether each is representing the dynamic properties of the structure in the same way. Specifically, whether: mode shapes are alike; the frequencies of the modes are alike; modes appear in the same frequency sequence; and if they are not alike, how to judge which to believe.

  12. Determinants of marriage dissolution

    NASA Astrophysics Data System (ADS)

    Rahim, Mohd Amirul Rafiq Abu; Shafie, Siti Aishah Mohd; Hadi, Az'lina Abdul; Razali, Nornadiah Mohd; Azid @ Maarof, Nur Niswah Naslina

    2015-10-01

    Nowadays, the number of divorce cases among Muslim couples is very worrisome whereby the total cases reported in 2013 increased by half of the total cases reported in the previous year. The questions on the true key factors of dissolution of marriage continue to arise. Thus, the objective of this study is to reveal the factors that contribute to the dissolution of marriage. A total of 181 cases and ten potential determinants were included in this study. The potential determinants considered were age at marriage of husband and wife, educational level of husband and wife, employment status of husband and wife, income of husband and wife, the number of children and the presence at a counseling session. Logistic regression analysis was used to analyze the data. The findings revealed that four determinants, namely the income of husband and wife, number of children and the presence at a counselling session were significant in predicting the likelihood of divorce among Muslim couples.

  13. Effect of particle size on solubility, dissolution rate, and oral bioavailability: evaluation using coenzyme Q10 as naked nanocrystals

    PubMed Central

    Sun, Jiao; Wang, Fan; Sui, Yue; She, Zhennan; Zhai, Wenjun; Wang, Chunling; Deng, Yihui

    2012-01-01

    In this paper work, four naked nanocrystals (size range 80–700 nm) were prepared without any surfactant or polymer using the solvent/nonsolvent method. The effects of particle size on their solubility, dissolution, and oral bioavailability were investigated. Solubility and dissolution testing were performed in three types of dissolution medium, and the studies demonstrated that the equilibrium solubilities of coenzyme Q10 nanocrystals and bulk drugs were not affected by the dissolution media but the kinetic solubilities were. Kinetic solubility curves and changes in particle size distribution were determined and well explained by the proposed solubilization model for the nanocrystals and bulk drugs. The particle size effect on dissolution was clearly influenced by the diffusion coefficients of the various dissolution media, and the dissolution velocity of coenzyme Q10 increased as particle size decreased. The bioavailability of coenzyme Q10 after oral administration in beagle dogs was improved by reducing the particle size. For 700 nm nanocrystals, the AUC0–48 was 4.4-fold greater than that for the coarse suspensions, but a further decrease in particle size from 700 nm to 120 nm did not contribute to improvement in bioavailability until the particle size was reduced to 80 nm, when bioavailability was increased by 7.3-fold. PMID:23166438

  14. Improved method for azole antifungal susceptibility testing.

    PubMed Central

    Gordon, M A; Lapa, E W; Passero, P G

    1988-01-01

    A reproducible method is described for the determination of the MICs of ketoconazole, miconazole, fluconazole, and itraconazole with sharp endpoints when employed with either yeasts or molds. A semisolid medium is used with controlled pH and standardized inoculum. The time of reading results is a critical factor in the conduct of this test. The medium is simple to prepare and has a relatively long refrigerator shelf life in a user-ready state, requiring only the addition of a freshly prepared inoculum after restoration to room temperature. Images PMID:2846651

  15. Comparison of three preservation techniques for slowing dissolution of calcareous nannofossils in organic rich sediments

    USGS Publications Warehouse

    Seefelt, Ellen L.; Self-Trail, Jean; Schultz, Arthur P.

    2015-01-01

    In an attempt to halt or reduce dissolution of calcareous nannofossils in organic and/or pyrite-rich sediments, three different methods of short-term storage preservation were tested for efficacy: vacuum packing, argon gas replacement, and buffered water. Abundance counts of calcareous nannofossil assemblages over a six month period showed that none of the three preservation methods were consistently effective in reducing assemblage loss due to dissolution. In most cases, the control slides made at the drill site had more abundant calcareous nannofossil assemblages than those slides made from sediments stored via vacuum packing, argon gas replacement, or buffered water. Thin section and XRD analyses showed that in most cases, <1% pyrite was needed to drive the oxidation-reduction reaction that resulted in dissolution, even in carbonate-rich sediments.

  16. Test methods for evaluating reformulated fuels

    SciTech Connect

    Croudace, M.C.

    1994-12-31

    The US Environmental Protection Agency (EPA) introduced regulations in the 1989 Clean Air Act Amendment governing the reformulation of gasoline and diesel fuels to improve air quality. These statutes drove the need for a fast and accurate method for analyzing product composition, especially aromatic and oxygenate content. The current method, gas chromatography, is slow, expensive, non portable, and requires a trained chemist to perform the analysis. The new mid-infrared spectroscopic method uses light to identify and quantify the different components in fuels. Each individual fuel component absorbs a specific wavelength of light depending on the molecule`s unique chemical structure. The quantity of light absorbed is proportional to the concentration of that fuel component in the mixture. The mid-infrared instrument has significant advantages; it is easy to use, rugged, portable, fully automated and cost effective. It can be used to measure multiple oxygenate or aromatic components in unknown fuel mixtures. Regulatory agencies have begun using this method in field compliance testing; petroleum refiners and marketers use it to monitor compliance, product quality and blending accuracy.

  17. Development of In Vitro-In Vivo Correlation/Relationship Modeling Approaches for Immediate Release Formulations Using Compartmental Dynamic Dissolution Data from “Golem”: A Novel Apparatus

    PubMed Central

    Čulen, Martin; Tuszyński, Paweł K.; Polak, Sebastian; Jachowicz, Renata; Mendyk, Aleksander; Dohnal, Jiří

    2015-01-01

    Different batches of atorvastatin, represented by two immediate release formulation designs, were studied using a novel dynamic dissolution apparatus, simulating stomach and small intestine. A universal dissolution method was employed which simulated the physiology of human gastrointestinal tract, including the precise chyme transit behavior and biorelevant conditions. The multicompartmental dissolution data allowed direct observation and qualitative discrimination of the differences resulting from highly pH dependent dissolution behavior of the tested batches. Further evaluation of results was performed using IVIVC/IVIVR development. While satisfactory correlation could not be achieved using a conventional deconvolution based-model, promising results were obtained through the use of a nonconventional approach exploiting the complex compartmental dissolution data. PMID:26120580

  18. Foucault test: a quantitative evaluation method.

    PubMed

    Rodríguez, Gustavo; Villa, Jesús; Ivanov, Rumen; González, Efrén; Martínez, Geminiano

    2016-08-01

    Reliable and accurate testing methods are essential to guiding the polishing process during the figuring of optical telescope mirrors. With the natural advancement of technology, the procedures and instruments used to carry out this delicate task have consistently increased in sensitivity, but also in complexity and cost. Fortunately, throughout history, the Foucault knife-edge test has shown the potential to measure transverse aberrations in the order of the wavelength, mainly when described in terms of physical theory, which allows a quantitative interpretation of its characteristic shadowmaps. Our previous publication on this topic derived a closed mathematical formulation that directly relates the knife-edge position with the observed irradiance pattern. The present work addresses the quite unexplored problem of the wavefront's gradient estimation from experimental captures of the test, which is achieved by means of an optimization algorithm featuring a proposed ad hoc cost function. The partial derivatives thereby calculated are then integrated by means of a Fourier-based algorithm to retrieve the mirror's actual surface profile. To date and to the best of our knowledge, this is the very first time that a complete mathematical-grounded treatment of this optical phenomenon is presented, complemented by an image-processing algorithm which allows a quantitative calculation of the corresponding slope at any given point of the mirror's surface, so that it becomes possible to accurately estimate the aberrations present in the analyzed concave device just through its associated foucaultgrams. PMID:27505659

  19. Foucault test: a quantitative evaluation method.

    PubMed

    Rodríguez, Gustavo; Villa, Jesús; Ivanov, Rumen; González, Efrén; Martínez, Geminiano

    2016-08-01

    Reliable and accurate testing methods are essential to guiding the polishing process during the figuring of optical telescope mirrors. With the natural advancement of technology, the procedures and instruments used to carry out this delicate task have consistently increased in sensitivity, but also in complexity and cost. Fortunately, throughout history, the Foucault knife-edge test has shown the potential to measure transverse aberrations in the order of the wavelength, mainly when described in terms of physical theory, which allows a quantitative interpretation of its characteristic shadowmaps. Our previous publication on this topic derived a closed mathematical formulation that directly relates the knife-edge position with the observed irradiance pattern. The present work addresses the quite unexplored problem of the wavefront's gradient estimation from experimental captures of the test, which is achieved by means of an optimization algorithm featuring a proposed ad hoc cost function. The partial derivatives thereby calculated are then integrated by means of a Fourier-based algorithm to retrieve the mirror's actual surface profile. To date and to the best of our knowledge, this is the very first time that a complete mathematical-grounded treatment of this optical phenomenon is presented, complemented by an image-processing algorithm which allows a quantitative calculation of the corresponding slope at any given point of the mirror's surface, so that it becomes possible to accurately estimate the aberrations present in the analyzed concave device just through its associated foucaultgrams.

  20. Mesh deployable antenna mechanics testing method

    NASA Astrophysics Data System (ADS)

    Jiang, Li

    Rapid development in spatial technologies and continuous expansion of astronautics applications require stricter and stricter standards in spatial structure. Deployable space structure as a newly invented structural form is being extensively adopted because of its characteristic (i.e. deployability). Deployable mesh reflector antenna is a kind of common deployable antennas. Its reflector consists in a kind of metal mesh. Its electrical properties are highly dependent on its mechanics parameters (including surface accuracy, angle, and position). Therefore, these mechanics parameters have to be calibrated. This paper presents a mesh antenna mechanics testing method that employs both an electronic theodolite and a laser tracker. The laser tracker is firstly used to measure the shape of radial rib deployable antenna. The measurement data are then fitted to a paraboloid by means of error compensation. Accordingly, the focus and the focal axis of the paraboloid are obtained. The following step is to synchronize the coordinate systems of the electronic theodolite and the measured antenna. Finally, in a microwave anechoic chamber environment, the electromechanical axis is calibrated. Testing results verify the effectiveness of the presented method.

  1. Comparative In Vitro Dissolution of Two Commercially Available Er-Zhi-Wan Herbal Medicinal Products

    PubMed Central

    Wang, M.; Jin, X.; Ren, X.; Zhu, Y.; Liu, Z.; Gao, X.

    2015-01-01

    In vitro dissolution test is an essential tool to assess the quality of herbal medicinal products in the solid dosage forms for oral use. Our work aimed to evaluate the dissolution behavior of Er-Zhi-Wan, in the formulations of water-honeyed pill and formula granule. Different media (water, 30% EtOH, 0.1 M HCl, acetate buffer, pH 4.5 and phosphate buffer, pH 6.8) were used following United States Pharmacopoeia and Chinese Pharmacopeia. An ultra-high performance liquid chromatography method was developed and validated to detect simultaneously six active ingredients for quantification and dissolution study (salidroside, specnuezhenide, nuezhenoside, luteolin, apigenin, oleanolic acid). As we observed, contents of main active ingredients were close in the two formulations for daily dose. In each medium, more ingredients dissolved from formula granule with higher Ymax and Ka. The mean dissolution time of the most ingredients in granule was significantly shorter than that in pill in acetate buffer, pH 4.5 and phosphate buffer, pH 6.8. Furthermore, salidroside, specnuezhenide and luteolin dissolved more than 80% in 30 min from formula granule, which indicated higher solubility along the intestinal tract according to biopharmaceutics classification system. The dissolution test developed and validated was adequate for its purposes and could be applied for quality control of herbal medicine. This work also can be used to provide necessary information on absorption for its biopharmaceutical properties. PMID:26664054

  2. Investigation of the release test method for the topical application of pharmaceutical preparations: release test of cataplasm including nonsteroidal anti-inflammatory drugs using artificial sweat.

    PubMed

    Shimamura, Takeshi; Tairabune, Tomohiko; Kogo, Tetsuo; Ueda, Hideo; Numajiri, Sachihiko; Kobayashi, Daisuke; Morimoto, Yasunori

    2004-02-01

    A simple procedure for determining the in vitro release profile of a cataplasm for use in a quality control procedure has been developed. Since the disk assembly in the USP for patch dosage forms was unsuited for use in a release test due to penetration of the dissolution medium into the cataplasm from the screw part of the device and the cataplasm swelled, new holders were designed. In the new holder, a cataplasm is held in position by sandwiching it between a stainless-steel O-ring and a silicon O-ring on the stainless steel board, 2 acrylic boards hold the O-rings and the stainless steal board, and the entire assembly is placed at the bottom of the dissolution vessel. The release profile was determined using the "Paddle over Disk" method in USP26. Furthermore, in order to prevent the swelling of the cataplasm, artificial sweat was used as the dissolution medium. The release profiles of the nine marketed brands of cataplasm containing indomethacin, ketoprofen, and flurbiprofen, respectively, were determined over a 12-h period. By adjusting the ion concentration and volume of the media, and the release surface-area of the cataplasm exposed to each medium, the procedure was found to be reproducible for in vitro release characterization of nine marketed brands. This shows that this technique can be used as a quality control tool for assuring product uniformity. PMID:14757999

  3. Fracture mechanics life analytical methods verification testing

    NASA Technical Reports Server (NTRS)

    Favenesi, J. A.; Clemons, T. G.; Riddell, W. T.; Ingraffea, A. R.; Wawrzynek, P. A.

    1994-01-01

    The objective was to evaluate NASCRAC (trademark) version 2.0, a second generation fracture analysis code, for verification and validity. NASCRAC was evaluated using a combination of comparisons to the literature, closed-form solutions, numerical analyses, and tests. Several limitations and minor errors were detected. Additionally, a number of major flaws were discovered. These major flaws were generally due to application of a specific method or theory, not due to programming logic. Results are presented for the following program capabilities: K versus a, J versus a, crack opening area, life calculation due to fatigue crack growth, tolerable crack size, proof test logic, tearing instability, creep crack growth, crack transitioning, crack retardation due to overloads, and elastic-plastic stress redistribution. It is concluded that the code is an acceptable fracture tool for K solutions of simplified geometries, for a limited number of J and crack opening area solutions, and for fatigue crack propagation with the Paris equation and constant amplitude loads when the Paris equation is applicable.

  4. Solubility limits on radionuclide dissolution

    SciTech Connect

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  5. Criticality safety in high explosives dissolution

    SciTech Connect

    Troyer, S.D.

    1997-06-01

    In 1992, an incident occurred at the Pantex Plant in which the cladding around a fissile material component (pit) cracked during dismantlement of the high explosives portion of a nuclear weapon. Although the event did not result in any significant contamination or personnel exposures, concerns about the incident led to the conclusion that the current dismantlement process was unacceptable. Options considered for redesign, dissolution tooling design considerations, dissolution tooling design features, and the analysis of the new dissolution tooling are summarized. The final tooling design developed incorporated a number of safety features and provides a simple, self-contained, low-maintenance method of high explosives removal for nuclear explosive dismantlement. Analyses demonstrate that the tooling design will remain subcritical under normal, abnormal, and credible accident scenarios. 1 fig.

  6. In vitro dissolution-permeation evaluation of an electrospun cyclodextrin-based formulation of aripiprazole using μFlux™.

    PubMed

    Borbás, Enikő; Balogh, Attila; Bocz, Katalin; Müller, Judit; Kiserdei, Éva; Vigh, Tamás; Sinkó, Bálint; Marosi, Attila; Halász, Attila; Dohányos, Zoltán; Szente, Lajos; Balogh, György T; Nagy, Zsombor K

    2015-08-01

    Since it is a well-known fact that among the newly discovered active pharmaceutical ingredients the number of poorly water soluble candidates is continually increasing, dissolution enhancement of poorly water soluble drugs has become one of the central challenges of pharmaceutical studies. So far the preclinical studies have been mainly focused on formulation methods to enhance the dissolution of active compounds, in many cases disregarding the fact that the formulation matrix not only affects dissolution but also has an effect on the transport through biological membranes, changing permeation of the drug molecules. The aim of this study was to test an electrospun cyclodextrin-based formulation of aripiprazole with the novel μFlux apparatus, which monitors permeation together with dissolution, and by this means better in vitro-in vivo correlation is achieved. It was evinced that a cyclodextrin-based electrospun formulation of aripiprazole has the potential to ensure fast drug delivery through the oral mucosa owing to the ultrafast dissolution of the drug from the formulation and the enhanced flux across membranes as shown by the result of the novel in vitro dissolution and permeation test.

  7. 40 CFR 63.1208 - What are the test methods?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 11 2010-07-01 2010-07-01 true What are the test methods? 63.1208 Section 63.1208 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... § 63.1208 What are the test methods? (a) (b) Test methods. You must use the following test methods...

  8. Testing methods and techniques: Environmental testing: A compilation

    NASA Technical Reports Server (NTRS)

    1971-01-01

    Various devices and techniques are described for testing hardware and components in four special environments: low temperature, high temperature, high pressure, and vibration. Items ranging from an automatic calibrator for pressure transducers to a fixture for testing the susceptibility of materials to ignition by electric spark are included.

  9. A Proposed Framework of Test Administration Methods

    ERIC Educational Resources Information Center

    Thompson, Nathan A.

    2008-01-01

    The widespread application of personal computers to educational and psychological testing has substantially increased the number of test administration methodologies available to testing programs. Many of these mediums are referred to by their acronyms, such as CAT, CBT, CCT, and LOFT. The similarities between the acronyms and the methods…

  10. A one-pot method to enhance dissolution rate of low solubility drug molecules using dispersion polymerization in supercritical carbon dioxide.

    PubMed

    Galia, Alessandro; Scialdone, Onofrio; Filardo, Giuseppe; Spanò, Tiziana

    2009-07-30

    The surfactant assisted polymerization of 1-vinyl-2-pyrrolidone in supercritical carbon dioxide in the presence of Piroxicam, selected as a model of a low aqueous solubility drug, was studied in order to prepare in a single step a polymeric composite to enhance the rate of dissolution of the pharmaceutical compound. Reactive entrapping was carried out at 65 degrees C in the P range 21-38MPa. Under proper operative conditions we obtained the composite under the form of sub-micron spherical particles with relatively narrow particle size distribution. Drug loadings higher than 12% (w/w) were obtained and XRD and Raman spectroscopy suggest that the anti-inflammatory agent is dispersed in the matrix with a non-crystalline structure. The dissolution rate of the drug from the composites was significantly faster both than that of the pure compound and of its physical mixture with the polymer. Collected results suggest that the proposed one-pot process can be used to prepare polymer based composites to increase bioavailability of low solubility drugs without utilization of toxic solvents and under mild temperature conditions.

  11. DISSOLUTION OF PLUTONIUM METAL IN 8-10 M NITRIC ACID

    SciTech Connect

    Rudisill, T.; Pierce, R.

    2012-02-21

    -10 M HNO{sub 3} with 0.04-0.05 M KF at 112 to 116 C (boiling). The testing also showed that solutions containing 8-10 M HNO{sub 3}, 0.1-0.2 M KF, and 1-2 g/L B achieved acceptable dissolution rates in the same temperature range. To confirm that conditions identified by the dissolution rate measurements for solutions containing Gd or B can be used to dissolve Pu metal up to 6.75 g/L in the presence of Fe, demonstration experiments were performed using concentrations in the optimal ranges. In two of the demonstration experiments using Gd and in one experiment using B, the offgas generation during the dissolution was measured and samples were analyzed for H{sub 2}. The experimental methods used to perform the dissolution rate measurements and flowsheet demonstrations and a discussion of the results are presented.

  12. Plutonium dissolution process

    DOEpatents

    Vest, M.A.; Fink, S.D.; Karraker, D.G.; Moore, E.N.; Holcomb, H.P.

    1994-01-01

    A two-step process for dissolving Pu metal is disclosed in which two steps can be carried out sequentially or simultaneously. Pu metal is exposed to a first mixture of 1.0-1.67 M sulfamic acid and 0.0025-0.1 M fluoride, the mixture having been heated to 45-70 C. The mixture will dissolve a first portion of the Pu metal but leave a portion of the Pu in an oxide residue. Then, a mineral acid and additional fluoride are added to dissolve the residue. Alternatively, nitric acid between 0.05 and 0.067 M is added to the first mixture to dissolve the residue as it is produced. Hydrogen released during the dissolution is diluted with nitrogen.

  13. Plutonium dissolution process

    DOEpatents

    Vest, Michael A.; Fink, Samuel D.; Karraker, David G.; Moore, Edwin N.; Holcomb, H. Perry

    1996-01-01

    A two-step process for dissolving plutonium metal, which two steps can be carried out sequentially or simultaneously. Plutonium metal is exposed to a first mixture containing approximately 1.0M-1.67M sulfamic acid and 0.0025M-0.1M fluoride, the mixture having been heated to a temperature between 45.degree. C. and 70.degree. C. The mixture will dissolve a first portion of the plutonium metal but leave a portion of the plutonium in an oxide residue. Then, a mineral acid and additional fluoride are added to dissolve the residue. Alteratively, nitric acid in a concentration between approximately 0.05M and 0.067M is added to the first mixture to dissolve the residue as it is produced. Hydrogen released during the dissolution process is diluted with nitrogen.

  14. Dissolution on Titan and on Earth: Towards the age of Titan's karstic landscapes

    NASA Astrophysics Data System (ADS)

    Cornet, T.; Cordier, D.; Le Bahers, T.; Bourgeois, O.; Fleurant, C.; Le Mouélic, S.; Altobelli, N.

    2015-10-01

    The morphology of Titan's lacustrine depressions led to comparisons with terrestrial depressions developed by karstic dissolution. We tested this hypothesis by computing dissolution rates of Titan's solids in liquid methane. We inferred from these rates the timescales needed to create dissolution landforms of a given depth. Dissolution would be a very efficient geological process to shape Titan's surface, on timescales generally shorter than 100 Myrs, consistent with the youth of Titan's surface (<1 Gyr).

  15. Successful topical dissolution of cholesterol gallbladder stones using ethyl propionate.

    PubMed

    Hofmann, A F; Amelsberg, A; Esch, O; Schteingart, C D; Lyche, K; Jinich, H; Vansonnenberg, E; D'Agostino, H B

    1997-06-01

    Topical dissolution of cholesterol gallbladder stones using methyl tert-butyl ether (MTBE) is useful in symptomatic patients judged too ill for surgery. Previous studies showed that ethyl propionate (EP), a C5 ester, dissolves cholesterol gallstones rapidly in vitro, but differs from MTBE in being eliminated so rapidly by the liver that blood levels remain undetectable. Our aim was to test EP as a topical dissolution agent for cholesterol gallbladder stones. Five high-risk patients underwent topical dissolution of gallbladder stones by EP. In three patients, the solvent was instilled via a cholecystostomy tube placed previously to treat acute cholecystitis; in two patients, a percutaneous transhepatic catheter was placed in the gallbladder electively. Gallstone dissolution was assessed by chromatography, by gravimetry, and by catheter cholecystography. Total dissolution of gallstones was obtained in four patients after 6-10 hr of lavage; in the fifth patient, partial gallstone dissolution facilitated basketing of the stones. In two patients, cholesterol dissolution was measured and averaged 30 mg/min. Side effects were limited to one episode of transient hypotension and pain at the infusion site; no patient developed somnolence or nausea. Gallstone elimination was associated with relief of symptoms. EP is an acceptable alternative to MTBE for topical dissolution of cholesterol gallbladder stones in high-risk patients. The lower volatility and rapid hepatic extraction of EP suggest that it may be preferable to MTBE in this investigational procedure.

  16. Dissolution Profile of Nimesulide from Pharmaceutical Preparations for Oral Use.

    PubMed

    Tubić, Biljana; Uzunović, Alija; Pilipović, Saša; Gagić, Žarko

    2016-01-01

    Nimesulide belongs to the group of semi-selective COX-2 inhibitors, widely used in solid oral formulations. In the present work the influence of surfactants among other drug excipients, as well as particle size of the active substance and the effects of medium pH on the dissolution rate of nimesulide from solid pharmaceutical forms. For that purpose, four different preparations containing 100 mg nimesulide per tablet and available in the market of Bosnia and Herzegovina (labeled here as A, B, C and D) were studied. The test for the assessment of dissolution profiles of the formulations was performed in surfactant-free dissolution medium pH 7.5. The dissolution profiles were compared by calculating difference (f1), and similarity (f2) factors. The increasing dissolution medium pH value from 7.5 to 7.75 resulted in a significant increase of nimesulide dissolution rate from the examined formulations. Also, the results showed that particle size affects to a great extent the dissolution rate and the best results were achieved with micronized nimesulide. The presence of the surfactants among the other excipients expressed a negligible effect on the dissolution profile.

  17. 49 CFR 383.133 - Testing methods.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... such a way as to determine if the applicant possesses the required knowledge and skills contained in... scoring the knowledge and skills tests. (d) Passing scores must meet those standards contained in § 383.135. (e) Knowledge and skills tests shall be based solely on the information contained in the...

  18. 40 CFR 63.365 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR part 60, appendix A, Test Methods 2, 2A, 2C, or 2D, as appropriate. (Method 2D (using orifice....) Record the flow rate at 1-minute intervals throughout the test cycle, taking the first reading within 15...) Test Method 18 or 25A, 40 CFR part 60, appendix A (hereafter referred to as Method 18 or...

  19. Fatigue crack growth automated testing method

    SciTech Connect

    Hatch, P.W.; VanDenAvyle, J.A.; Laing, J.

    1989-06-01

    A computer controlled servo-hydraulic mechanical test system has been configured to conduct automated fatigue crack growth testing. This provides two major benefits: it allows continuous cycling of specimens without operator attention over evenings and weekends; and complex load histories, including random loading and spectrum loading, can be applied to the specimens to simulate cyclic loading of engineering structures. The software is written in MTS Multi-User Basic to control test machine output and acquire data at predetermined intervals. Compact tension specimens are cycled according to ASTM specification E647-86. Fatigue crack growth is measured via specimen compliance during the test using a compliance/crack length calibration determined earlier by visual crack length measurements. This setup was used to measure crack growth rates in 6063 aluminum alloy for a variety of cyclic loadings, including spectrum loads. Data collected compared well with tests run manually. 13 figs.

  20. Efavirenz Dissolution Enhancement I: Co-Micronization

    PubMed Central

    da Costa, Maíra Assis; Seiceira, Rafael Cardoso; Rodrigues, Carlos Rangel; Hoffmeister, Cristiane Rodrigues Drago; Cabral, Lucio Mendes; Rocha, Helvécio Vinícius Antunes

    2012-01-01

    AIDS constitutes one of the most serious infectious diseases, representing a major public health priority. Efavirenz (EFV), one of the most widely used drugs for this pathology, belongs to the Class II of the Biopharmaceutics Classification System for drugs with very poor water solubility. To improve EFV’s dissolution profile, changes can be made to the physical properties of the drug that do not lead to any accompanying molecular modifications. Therefore, the study objective was to develop and characterize systems with efavirenz able to improve its dissolution, which were co-processed with sodium lauryl sulfate (SLS) and polyvinylpyrrolidone (PVP). The technique used was co-micronization. Three different drug:excipient ratios were tested for each of the two carriers. The drug dispersion dissolution results showed significant improvement for all the co-processed samples in comparison to non-processed material and corresponding physical mixtures. The dissolution profiles obtained for dispersion with co-micronized SLS samples proved superior to those of co-micronized PVP, with the proportion (1:0.25) proving the optimal mixture. The improvements may be explained by the hypothesis that formation of a hydrophilic layer on the surface of the micronized drug increases the wettability of the system formed, corroborated by characterization results indicating no loss of crystallinity and an absence of interaction at the molecular level. PMID:24300394

  1. Evaluation of the test method activated sludge, respiration inhibition test proposed by the OECD

    SciTech Connect

    Yoshioka, Y.; Nagase, H.; Ose, Y.; Sato, T.

    1986-12-01

    The test method of activated sludge, respiration inhibition test proposed by the OECD was critically carried out and compared with other test methods. Investigation of test conditions showed that the moderate deviation from the test conditions defined by the OECD Test Guidelines did not have much effect on the result, and some modifications were proposed to improve the method. This method had a poor detection limit compared with the LC50 test with Oryzias latipes and EC50 of the growth inhibition test with Tetrahymena pyriformis. The susceptivity of the method was particularly poor for the chemicals which were highly toxic in the other two tests.

  2. Analysis of Formation and Interfacial WC Dissolution Behavior of WC-Co/Invar Laser-TIG Welded Joints

    NASA Astrophysics Data System (ADS)

    Xu, P. Q.; Ren, J. W.; Zhang, P. L.; Gong, H. Y.; Yang, S. L.

    2013-02-01

    During the valve fabrication, hard metal is welded to stainless steel or invar alloy for sealing purposes because of its good heat resistance operating at 500 °C. However, WC (tungsten carbide) dissolution in weld pool softens the hard metal and decreases mechanical properties near the hard metal/weld interface. In order to analyze the WC dissolution in welded joint, joining of hard metal and invar alloy was carried out using laser-tungsten inert gas hybrid welding method. Microstructures of the weld region, chemical composition were investigated using optical microscope, scanning electron microscopy, and EDAX, respectively. Mechanical properties such as microhardness and four-point bend strength test were performed. Larger and smaller WC dissolution and WC dissolution through transition layer based on thermo-dynamics were discussed. The results thus indicate that WC dissolution led to cellular microstructure, columnar crystal, and transition layer under the effect of laser beam and tungsten arc. WC dissolution was affected by metal ions Fe+, Ni+, Co+ exchange in W-M-C system, and WC grain growth was driven by forces caused by laser beam and tungsten arc in larger WC, smaller WC, and liquid Fe, Ni systems.

  3. Ego-Dissolution and Psychedelics: Validation of the Ego-Dissolution Inventory (EDI)

    PubMed Central

    Nour, Matthew M.; Evans, Lisa; Nutt, David; Carhart-Harris, Robin L.

    2016-01-01

    Aims: The experience of a compromised sense of “self”, termed ego-dissolution, is a key feature of the psychedelic experience. This study aimed to validate the Ego-Dissolution Inventory (EDI), a new 8-item self-report scale designed to measure ego-dissolution. Additionally, we aimed to investigate the specificity of the relationship between psychedelics and ego-dissolution. Method: Sixteen items relating to altered ego-consciousness were included in an internet questionnaire; eight relating to the experience of ego-dissolution (comprising the EDI), and eight relating to the antithetical experience of increased self-assuredness, termed ego-inflation. Items were rated using a visual analog scale. Participants answered the questionnaire for experiences with classical psychedelic drugs, cocaine and/or alcohol. They also answered the seven questions from the Mystical Experiences Questionnaire (MEQ) relating to the experience of unity with one’s surroundings. Results: Six hundred and ninety-one participants completed the questionnaire, providing data for 1828 drug experiences (1043 psychedelics, 377 cocaine, 408 alcohol). Exploratory factor analysis demonstrated that the eight EDI items loaded exclusively onto a single common factor, which was orthogonal to a second factor comprised of the items relating to ego-inflation (rho = −0.110), demonstrating discriminant validity. The EDI correlated strongly with the MEQ-derived measure of unitive experience (rho = 0.735), demonstrating convergent validity. EDI internal consistency was excellent (Cronbach’s alpha 0.93). Three analyses confirmed the specificity of ego-dissolution for experiences occasioned by psychedelic drugs. Firstly, EDI score correlated with drug-dose for psychedelic drugs (rho = 0.371), but not for cocaine (rho = 0.115) or alcohol (rho = −0.055). Secondly, the linear regression line relating the subjective intensity of the experience to ego-dissolution was significantly steeper for psychedelics

  4. An eco-friendly strategy, using on-line monitoring and dilution coupled to a second-order chemometric method, for the construction of dissolution curves of combined pharmaceutical associations.

    PubMed

    Calvo, Natalia L; Maggio, Rubén M; Kaufman, Teodoro S

    2014-02-01

    A simple, precise, economic and minimally operator-dependent method was developed under green analytical chemistry principles, for the simultaneous construction of the dissolution curves of a pharmaceutical association in short time and without employing organic solvents, allowing important savings of labor and resources. The carvedilol (CAR) and hydrochlorothiazide (HCT) combined formulation was employed as a model. The method (OD/UV-MCR) involves on-line sample dilution (OD) and UV detection of the analytes, coupled to multivariate curve resolution with alternating least squares (MCR-ALS). OD/UV-MCR proved to be robust and was successfully validated in accordance to ICH guidelines, fulfilling acceptance criteria for specificity (r(2) of spectral correlation>0.950), linearity [r>0.999 (N=25) in the ranges 1.00-31.1mg l(-1) and 0.51-15.2mg l(-1) for CAR and HCT, respectively] and precision (RSD<2%). Accuracy was assessed by point-to-point comparison between the dissolution profiles furnished by the proposed method with those provided by HPLC analysis, evidencing the usefulness of this monitoring system. In addition, OD/UV-MCR was successfully employed for the comparative analysis of three lots of commercial formulations of the CAR-HCT pharmaceutical association, belonging to a couple of different brands, employing Moore and Flanner's f2 similarity indicator. PMID:24291800

  5. An eco-friendly strategy, using on-line monitoring and dilution coupled to a second-order chemometric method, for the construction of dissolution curves of combined pharmaceutical associations.

    PubMed

    Calvo, Natalia L; Maggio, Rubén M; Kaufman, Teodoro S

    2014-02-01

    A simple, precise, economic and minimally operator-dependent method was developed under green analytical chemistry principles, for the simultaneous construction of the dissolution curves of a pharmaceutical association in short time and without employing organic solvents, allowing important savings of labor and resources. The carvedilol (CAR) and hydrochlorothiazide (HCT) combined formulation was employed as a model. The method (OD/UV-MCR) involves on-line sample dilution (OD) and UV detection of the analytes, coupled to multivariate curve resolution with alternating least squares (MCR-ALS). OD/UV-MCR proved to be robust and was successfully validated in accordance to ICH guidelines, fulfilling acceptance criteria for specificity (r(2) of spectral correlation>0.950), linearity [r>0.999 (N=25) in the ranges 1.00-31.1mg l(-1) and 0.51-15.2mg l(-1) for CAR and HCT, respectively] and precision (RSD<2%). Accuracy was assessed by point-to-point comparison between the dissolution profiles furnished by the proposed method with those provided by HPLC analysis, evidencing the usefulness of this monitoring system. In addition, OD/UV-MCR was successfully employed for the comparative analysis of three lots of commercial formulations of the CAR-HCT pharmaceutical association, belonging to a couple of different brands, employing Moore and Flanner's f2 similarity indicator.

  6. 40 CFR 63.547 - Test methods.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... gas. (5) EPA Method 23 at 40 CFR part 60, appendix A-7 to determine the dioxins and furans... at 40 CFR part 60, appendix A-1 to select the sampling port location and the number of traverse points. (2) EPA Method 2 at 40 CFR part 60, appendix A-1 or EPA Method 5D at 40 CFR part 60, appendix...

  7. 40 CFR 63.547 - Test methods.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... gas. (5) EPA Method 23 at 40 CFR part 60, appendix A-7 to determine the dioxins and furans... at 40 CFR part 60, appendix A-1 to select the sampling port location and the number of traverse points. (2) EPA Method 2 at 40 CFR part 60, appendix A-1 or EPA Method 5D at 40 CFR part 60, appendix...

  8. Experimental characterization of composites. [load test methods

    NASA Technical Reports Server (NTRS)

    Bert, C. W.

    1975-01-01

    The experimental characterization for composite materials is generally more complicated than for ordinary homogeneous, isotropic materials because composites behave in a much more complex fashion, due to macroscopic anisotropic effects and lamination effects. Problems concerning the static uniaxial tension test for composite materials are considered along with approaches for conducting static uniaxial compression tests and static uniaxial bending tests. Studies of static shear properties are discussed, taking into account in-plane shear, twisting shear, and thickness shear. Attention is given to static multiaxial loading, systematized experimental programs for the complete characterization of static properties, and dynamic properties.

  9. Subscale Test Methods for Combustion Devices

    NASA Technical Reports Server (NTRS)

    Anderson, W. E.; Sisco, J. C.; Long, M. R.; Sung, I.-K.

    2005-01-01

    Stated goals for long-life LRE s have been between 100 and 500 cycles: 1) Inherent technical difficulty of accurately defining the transient and steady state thermochemical environments and structural response (strain); 2) Limited statistical basis on failure mechanisms and effects of design and operational variability; and 3) Very high test costs and budget-driven need to protect test hardware (aversion to test-to-failure). Ambitious goals will require development of new databases: a) Advanced materials, e.g., tailored composites with virtually unlimited property variations; b) Innovative functional designs to exploit full capabilities of advanced materials; and c) Different cycles/operations. Subscale testing is one way to address technical and budget challenges: 1) Prototype subscale combustors exposed to controlled simulated conditions; 2) Complementary to conventional laboratory specimen database development; 3) Instrumented with sensors to measure thermostructural response; and 4) Coupled with analysis

  10. Economical test methods for developmental neurobehavioral toxicity.

    PubMed

    Bignami, G

    1996-04-01

    The assessment of behavioral changes produced by prenatal or early postnatal exposure to potentially noxious agents requires both the designing of ad hoc tests and the adaptation of tests for adult animals to the characteristics of successive developmental stages. The experience in designing tests is still more limited than in the adaptation of tests, but several tests have already proven their usefulness; some examples are the suckling test, the homing test, and evaluations of dam-pup and pup-pup interactions. Functional observational batteries can exploit the development at specified postnatal ages of several reflexes and responses that are absent at birth in altricial rodent species with a short pregnancy such as the rat and the mouse. In neonates, the assessment of early treatment effects can rely not only on deviations from normal responding but also on changes in the time of appearance of otherwise normal response patterns. The same applies to other end points such as responses to pain and various types of spontaneous motor/exploratory activities, including reactivity to a variety of drug challenges that can provide information on the regulatory systems whose development may be affected by early treatments. In particular, the analysis of ontogenetic dissociations (i.e., differential early treatment effects depending jointly on developmental stage at the time of exposure, age of testing, and response end point) can be of considerable value in the study of treatments' mechanisms of action. Overall, it appears that behavioral teratological assessments can be effectively used both proactively, i.e., in risk assessment prior to any human exposure, and reactively. In the latter case, these assessments could have special value in the face of agents suspected to produce borderline changes in developing humans, whose innocuousness or noxiousness can be difficult to establish in the absence of hard evidence of teratogenicity.

  11. Saltcake Dissolution FY 2000 Status Report

    SciTech Connect

    HERTING, D.L.

    2000-09-27

    Laboratory tests were completed on the dissolution characteristics of Hanford saltcake waste from single-shell waste tanks 241-TX- 113, 241-BY-102, 241-BY-106, 241-A-101, and 241-S-102 (henceforth referred to as TX-113, BY-102, BY-106, A-101, and S-102, respectively). This work was funded by the Tanks Focus Area (EM-50) under Technical Task Plan Number RL0-8-WT-41, ''PHMC Pretreatment--Saltcake Dissolution''. The tests performed on saltcake from tank TX-113 were similar in scope to those completed in previous years on waste from tanks BY-102, BY-106, B-106, A-101, and S-102 (Herting 1998, 1999). In addition to the ''standard'' dissolution tests, new types of tests were performed this year related to feed stability and radionuclide distribution. The River Protection Project (RPP) is tasked with retrieving waste from double-shell and single-shell tanks to provide feed for vitrification. The RPP organization needs chemical and physical data to evaluate technologies for retrieving the waste. Little significant laboratory testing has been done to evaluate in-tank dissolution parameters for the various types of saltcake wastes that exist in single-shell tanks. A computer modeling program known as the Environmental Simulation Program (ESP), produced by OLI Systems, Inc of Morris Plains, New Jersey, is being used by the RPP organization to predict solubilities during dilution and retrieval of all tank waste types. Data from this task are provided to ESP users to support evaluation, refinement, and validation of the ESP model.

  12. Influence of rapeseed phospholipids on ibuprofen dissolution from solid dispersions.

    PubMed

    Sosada, M; Gorecki, M; Pasker, B

    2006-08-01

    The dissolution profiles of ibuprofen (IB) from solid dispersions prepared by the solvent evaporation method, containing the rapeseed lecithin ethanol soluble fraction (LESF) or rapeseed phosphatidylcholine (RPC) have been determined. The effect of incorporation of PEG 4,000 or PEG 8,000 in the solid dispersions on the controlled-release of IB was also investigated. Dissolution studies conducted in double-distilled water using the paddle dissolution apparatus showed that the initial dissolution rate (IDR) within the first 5 min and the maximum percent of dissolved IB of IB/LESF were double of those of IB/RPC (both in ratio 4:1 w/w). The low amounts of LESF markedly increased dissolution of IB. Increasing of LESF concentration from 0 to 10 and 20% in solid dispersions produced 60 and 100% improvement of IB maximum dissolution level respectively, to compare with that of IB alone. PEG 4,000 caused the slightly decreasing in IB dissolution rate, while PEG 8,000 markedly improved the dissolution of IB in examined conditions.

  13. Dissolution enhancement of chlorzoxazone using cogrinding technique

    PubMed Central

    Raval, Mihir K.; Patel, Jaydeep M.; Parikh, Rajesh K.; Sheth, Navin R.

    2015-01-01

    Purpose: The aim of the present work was to improve rate of dissolution and processing parameters of BCS class II drug, chlorzoxazone using cogrinding technique in the presence of different excipients as a carrier. Materials and Methods: The drug was coground with various carriers like polyethylene glycol (PEG 4000), hydroxypropyl methylcellulose (HPMC) E50LV, polyvinylpyrrolidone (PVP)K30, Kaolin and Neusilin US2 using ball mill, where only PEG 4000 improved dissolution rate of drug by bringing amorphization in 1:3 ratio. The coground mixture after 3 and 6 h was evaluated for various analytical, physicochemical and mechanical parameters. Results: The analysis showed conversion of Chlorzoxazone from its crystalline to amorphization form upon grinding with PEG 4000. Coground mixture as well as its directly compressed tablet showed 2.5-fold increment in the dissolution rate compared with pure drug. Directly compressible tablets prepared from pure drug required a large quantity of microcrystalline cellulose (MCC) during compression. The coground mixture and formulation was found stable in nature even after storage (40°C/75% relative humidity). Conclusions: Cogrinding can be successfully utilized to improve the rate of dissolution of poorly water soluble drugs and hence bioavailability. PMID:26682195

  14. 40 CFR Appendix A to Part 63 - Test Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ....2.1A clearly written test method, preferably in the format of 40 CFR part 60, appendix A Test... reference from other methods in appendix A to 40 CFR part 60. Therefore, to obtain reliable results,...

  15. Apparatus and method for testing fuel injectors

    SciTech Connect

    Bunch, R.L.; Dillard, H.G.

    1991-03-19

    This patent describes a system for testing the efficacy of a fuel injector having a fuel injection valve and a nozzle with at least one orifice for injecting fuel therethrough. It includes a fluid manifold having fluid passages therein, and having mounting means for receiving a fuel injector to be tested and for holding the fuel injector in fluid communication with the fluid passages and with the nozzle depending from the manifold; means for supplying a testing fluid under pressure to the manifold fluid passages; a support disposed below the nozzle and having a drain port therein; means selectively mountable on the support in a first test phase and extending upwardly therefrom circumjacent the nozzle for providing visual inspection of the nozzle, the means having an opening at the bottom thereof for communication with the drain port; a measuring means selectively mountable on the support and extending upwardly therefrom circumjacent the nozzle in lieu of the visual inspection means in another test phase, the measuring means being closed at the bottom thereof; quick change means.

  16. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A...

  17. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 14 2011-07-01 2011-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60....

  18. 40 CFR Table 3 of Subpart Bbbbbbb... - Test Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Test Methods 3 Table 3 of Subpart... 3 Table 3 of Subpart BBBBBBB of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A in appendix A to part 60....

  19. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 15 2012-07-01 2012-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A...

  20. 40 CFR Table 3 of Subpart Aaaaaaa... - Test Methods

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 14 2010-07-01 2010-07-01 false Test Methods 3 Table 3 of Subpart..., Subpt. AAAAAAA, Table 3 Table 3 of Subpart AAAAAAA of Part 63—Test Methods For * * * You must use * * * 1. Selecting the sampling locations a and the number of traverse points EPA test method 1 or 1A...

  1. Evaluation of SSME test data reduction methods

    NASA Technical Reports Server (NTRS)

    Santi, L. Michael

    1994-01-01

    Accurate prediction of hardware and flow characteristics within the Space Shuttle Main Engine (SSME) during transient and main-stage operation requires a significant integration of ground test data, flight experience, and computational models. The process of integrating SSME test measurements with physical model predictions is commonly referred to as data reduction. Uncertainties within both test measurements and simplified models of the SSME flow environment compound the data integration problem. The first objective of this effort was to establish an acceptability criterion for data reduction solutions. The second objective of this effort was to investigate the data reduction potential of the ROCETS (Rocket Engine Transient Simulation) simulation platform. A simplified ROCETS model of the SSME was obtained from the MSFC Performance Analysis Branch . This model was examined and tested for physical consistency. Two modules were constructed and added to the ROCETS library to independently check the mass and energy balances of selected engine subsystems including the low pressure fuel turbopump, the high pressure fuel turbopump, the low pressure oxidizer turbopump, the high pressure oxidizer turbopump, the fuel preburner, the oxidizer preburner, the main combustion chamber coolant circuit, and the nozzle coolant circuit. A sensitivity study was then conducted to determine the individual influences of forty-two hardware characteristics on fourteen high pressure region prediction variables as returned by the SSME ROCETS model.

  2. Tracer Test Interpretation Methods for Reservior Properties

    SciTech Connect

    Shook, George Michael

    2001-08-01

    The purpose of this project is to develop tools that can be used to interpret tracer tests and obtain estimates of reservoir and operational parameters. These tools (mostly in the form of spreadsheet applications) can be used to optimize geothermal resource management.

  3. 40 CFR 63.547 - Test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... at 40 CFR part 60, appendix A-1 to select the sampling port location and the number of traverse points. (2) EPA Method 2 at 40 CFR part 60, appendix A-1 or EPA Method 5D at 40 CFR part 60, appendix A-3..., or 3B at 40 CFR part 60, appendix A-2 to determine the dry molecular weight of the stack gas. (4)...

  4. In vivo dissolution measurement with indium-111 summation peak ratios

    SciTech Connect

    Jay, M.; Woodward, M.A.; Brouwer, K.R.

    1985-10-01

    Dissolution of (/sup 111/In)labeled tablets was measured in vivo in a totally noninvasive manner by using a modification of the perturbed angular correlation technique known as the summation peak ratio method. This method, which requires the incorporation of only 10-12 microCi into the dosage form, provided reliable dissolution data after oral administration of (/sup 111/In)lactose tablets. These results were supported by in vitro experiments which demonstrated that the dissolution rate as measured by the summation peak ratio method was in close agreement with the dissolution rate of salicylic acid in a (/sup 111/In)salicylic acid tablet. The method has the advantages of using only one detector, thereby avoiding the need for complex coincidence counting systems, requiring less radioactivity, and being potentially applicable to a gamma camera imaging system.

  5. Handbook of test methods for evaluating chemical deicers

    SciTech Connect

    Chappelow, C.C.; McElroy, A.D.; Blackburn, R.R.; Darwin, D.; de Noyelles, F.G.

    1992-11-01

    The handbook contains a structured selection of specific test methods for complete characterization of deicing chemicals. Sixty-two specific test methods are defined for the evaluation of chemical deicers in eight principal property performance areas: (1) physicochemical characteristics; (2) deicing performance; (3) compatibility with bare and coated metals; (4) compatibility with metals in concrete; (5) compatibility with concrete and nonmetals; (6) engineering parameters; (7) ecological effects; and (8) health and safety aspects. The 62 specific chemical deicer test methods are composed of 12 primary and 50 supplementary test methods. The primary test methods, which were developed for conducting the more important evaluations, are identified in the report.

  6. A Novel Approach to Experimental Studies of Mineral Dissolution Kinetics

    SciTech Connect

    Chen Zhu; William E. Seyfried

    2005-01-01

    Currently, DOE is conducting pilot CO{sub 2} injection tests to evaluate the concept of geological sequestration. One strategy that potentially enhances CO{sub 2} solubility and reduces the risk of CO{sub 2} leak back to the surface is dissolution of indigenous minerals in the geological formation and precipitation of secondary carbonate phases, which increases the brine pH and immobilizes CO{sub 2}. Clearly, the rates at which these dissolution and precipitation reactions occur directly determine the efficiency of this strategy. However, one of the fundamental problems in modern geochemistry is the persistent two to five orders of magnitude discrepancy between laboratory-measured and field derived feldspar dissolution rates. To date, there is no real guidance as to how to predict silicate reaction rates for use in quantitative models. Current models for assessment of geological carbon sequestration have generally opted to use laboratory rates, in spite of the dearth of such data for compositionally complex systems, and the persistent disconnect between lab and field applications. Therefore, a firm scientific basis for predicting silicate reaction kinetics in CO{sub 2} injected geological formations is urgently needed to assure the reliability of the geochemical models used for the assessments of carbon sequestration strategies. The funded experimental and theoretical study attempts to resolve this outstanding scientific issue by novel experimental design and theoretical interpretation to measure silicate dissolution rates and iron carbonate precipitation rates at conditions pertinent to geological carbon sequestration. In the first year of the project, we have successfully developed a sample preparation method and completed three batch feldspar dissolution experiments at 200 C and 300 bars. The changes of solution chemistry as dissolution experiments progressed were monitored with on-line sampling of the aqueous phase at the constant temperature and pressure

  7. Drug susceptibility testing by dilution methods.

    PubMed

    Jeannot, Katy; Plésiat, Patrick

    2014-01-01

    Serial twofold dilution methods are widely used to assess the bacteriostatic activities of antibiotics. This can be achieved by dilution of considered drugs in agar medium or in culture broth, and inoculation by calibrated inoculums. Although seemingly simple, these methods are greatly influenced by the experimental conditions used and may lead to discrepant results, in particular with untrained investigators. The present step-by-step protocol has been validated for Pseudomonas species, including P. aeruginosa. Introduction of appropriate control strains is crucial to ascertain minimal inhibitory concentration values and compare the results of independent experiments.

  8. Phase II of a Six sigma Initiative to Study DWPF SME Analytical Turnaround Times: SRNL's Evaluation of Carbonate-Based Dissolution Methods

    SciTech Connect

    Edwards, Thomas

    2005-09-01

    The Analytical Development Section (ADS) and the Statistical Consulting Section (SCS) of the Savannah River National Laboratory (SRNL) are participating in a Six Sigma initiative to improve the Defense Waste Processing Facility (DWPF) Laboratory. The Six Sigma initiative has focused on reducing the analytical turnaround time of samples from the Slurry Mix Evaporator (SME) by developing streamlined sampling and analytical methods [1]. The objective of Phase I was to evaluate the sub-sampling of a larger sample bottle and the performance of a cesium carbonate (Cs{sub 2}CO{sub 3}) digestion method. Successful implementation of the Cs{sub 2}CO{sub 3} fusion method in the DWPF would have important time savings and convenience benefits because this single digestion would replace the dual digestion scheme now used. A single digestion scheme would result in more efficient operations in both the DWPF shielded cells and the inductively coupled plasma--atomic emission spectroscopy (ICP-AES) laboratory. By taking a small aliquot of SME slurry from a large sample bottle and dissolving the vitrified SME sample with carbonate fusion methods, an analytical turnaround time reduction from 27 hours to 9 hours could be realized in the DWPF. This analytical scheme has the potential for not only dramatically reducing turnaround times, but also streamlining operations to minimize wear and tear on critical shielded cell components that are prone to fail, including the Hydragard{trademark} sampling valves and manipulators. Favorable results from the Phase I tests [2] led to the recommendation for a Phase II effort as outlined in the DWPF Technical Task Request (TTR) [3]. There were three major tasks outlined in the TTR, and SRNL issued a Task Technical and QA Plan [4] with a corresponding set of three major task activities: (1) Compare weight percent (wt%) total solids measurements of large volume samples versus peanut vial samples. (2) Evaluate Cs{sub 2}CO{sub 3} and K{sub 2}CO{sub 3

  9. A method to assess the ranking importance of uncertainties of residual and dissolution trapping of CO2 on a large-scale storage site

    NASA Astrophysics Data System (ADS)

    Audigane, P.; Rohmer, J.; Manceau, J. C.

    2014-12-01

    The long term fate of mobile CO2 remaining after the injection period is a crucial issue for regulators and operators. There are needs to evaluate properly the amount of gas free to migrate and to estimate the fluid movements at long time scales. Often the difficulty is to manage the computational time to assess the large time and dimension scale of the problem. The second limitation is the large level of uncertainty associated to the computation prediction. A variance-based global sensitivity analysis is proposed to assess the importance ranking of uncertainty sources, with regards to the behavior of the mobile CO2 during the post-injection period. We consider three output parameters which characterize the location and the quantity of mobile CO2, considering residual and dissolution trapping. To circumvent both (i) the large number of computationally intensive reservoir-scale flow simulations and (ii) the different nature of uncertainties whether linked to parameters (continuous variables) or to modeling assumptions (scenario-like variables) we propose to use advanced meta-modeling techniques of ACOSSO-type. The feasibility of the approach is demonstrated using a potential site for CO2 storage in the Paris basin (France), for which the amount, nature and quality of the data available at disposal and the associated uncertainties can be seen as representative to those of a storage project at the post-screening stage. A special attention has been paid to confront the results of the sensitivity analysis with the physical interpretation of the processes.

  10. 40 CFR 60.534 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Wood Heaters § 60.534 Test methods and procedures. Test methods and procedures in appendix A of this...) Method 5H, if a stack location is used. (c) Method 28A shall be used to determine that a wood combustion unit qualifies under the definition of wood heater in § 60.531(a). If such a determination is...

  11. 40 CFR 60.534 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Wood Heaters § 60.534 Test methods and procedures. Test methods and procedures in appendix A of this...) Method 5H, if a stack location is used. (c) Method 28A shall be used to determine that a wood combustion unit qualifies under the definition of wood heater in § 60.531(a). If such a determination is...

  12. 40 CFR 60.534 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Wood Heaters § 60.534 Test methods and procedures. Test methods and procedures in appendix A of this...) Method 5H, if a stack location is used. (c) Method 28A shall be used to determine that a wood combustion unit qualifies under the definition of wood heater in § 60.531(a). If such a determination is...

  13. 40 CFR 61.164 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... results of three 60-minute test runs. (ii) Use the following methods in appendix A to 40 CFR part 60: (A... glass melting furnace. (ii) Use the following methods in appendix A to 40 CFR part 60: (A) Method 1 for... Arsenic Emissions From Glass Manufacturing Plants § 61.164 Test methods and procedures. (a) To...

  14. 40 CFR 61.164 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... results of three 60-minute test runs. (ii) Use the following methods in appendix A to 40 CFR part 60: (A... glass melting furnace. (ii) Use the following methods in appendix A to 40 CFR part 60: (A) Method 1 for... Arsenic Emissions From Glass Manufacturing Plants § 61.164 Test methods and procedures. (a) To...

  15. 40 CFR 61.164 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... results of three 60-minute test runs. (ii) Use the following methods in appendix A to 40 CFR part 60: (A... glass melting furnace. (ii) Use the following methods in appendix A to 40 CFR part 60: (A) Method 1 for... Arsenic Emissions From Glass Manufacturing Plants § 61.164 Test methods and procedures. (a) To...

  16. 40 CFR 61.164 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... results of three 60-minute test runs. (ii) Use the following methods in appendix A to 40 CFR part 60: (A... glass melting furnace. (ii) Use the following methods in appendix A to 40 CFR part 60: (A) Method 1 for... Arsenic Emissions From Glass Manufacturing Plants § 61.164 Test methods and procedures. (a) To...

  17. 40 CFR 60.534 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Wood Heaters § 60.534 Test methods and procedures. Test methods and procedures in appendix A of this...) Method 5H, if a stack location is used. (c) Method 28A shall be used to determine that a wood combustion unit qualifies under the definition of wood heater in § 60.531(a). If such a determination is...

  18. 40 CFR 60.534 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Wood Heaters § 60.534 Test methods and procedures. Test methods and procedures in appendix A of this...) Method 5H, if a stack location is used. (c) Method 28A shall be used to determine that a wood combustion unit qualifies under the definition of wood heater in § 60.531(a). If such a determination is...

  19. 40 CFR 766.16 - Developing the analytical test method.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... analytical test method. Because of the matrix differences of the chemicals listed for testing, no one method... to separate the HDDs/HDFs from the sample matrix. Methods are reviewed in the Guidelines under § 766... meet the requirements of the chemical matrix. (d) Analysis. The method of choice is High Resolution...

  20. 40 CFR 63.365 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... be determined by either: (A) Weighing the ethylene oxide gas cylinder(s) used to charge the... CFR part 60, appendix A, Test Methods 2, 2A, 2C, or 2D, as appropriate. (Method 2D (using orifice...) Test Method 18 or 25A, 40 CFR part 60, appendix A (hereafter referred to as Method 18 or...

  1. 40 CFR 63.365 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... be determined by either: (A) Weighing the ethylene oxide gas cylinder(s) used to charge the... CFR part 60, appendix A, Test Methods 2, 2A, 2C, or 2D, as appropriate. (Method 2D (using orifice...) Test Method 18 or 25A, 40 CFR part 60, appendix A (hereafter referred to as Method 18 or...

  2. Low-cycle fatigue testing methods

    NASA Technical Reports Server (NTRS)

    Lieurade, H. P.

    1978-01-01

    The good design of highly stressed mechanical components requires accurate knowledge of the service behavior of materials. The main methods for solving the problems of designers are: determination of the mechanical properties of the material after cyclic stabilization; plotting of resistance to plastic deformation curves; effect of temperature on the life on low cycle fatigue; and simulation of notched parts behavior.

  3. Experimental Tests of Subjective Bayesian Methods

    ERIC Educational Resources Information Center

    Li,Yuelin; Krantz, David H.

    2005-01-01

    We evaluated Samaniego and Reneau's 1994 novel weight method for eliciting subjective probability estimates. Experiment 1 replicated their experiment (subjects weighed their prior estimate against 10 new observations), with an additional weight judgment against 50 observations. In Experiment 2, subjects gave prior estimates to questions in a…

  4. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 28 2012-07-01 2012-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  5. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 27 2014-07-01 2014-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  6. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 27 2011-07-01 2011-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  7. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of.... 268, App. IX Appendix IX to Part 268—Extraction Procedure (EP) Toxicity Test Method and...

  8. Method and apparatus for container leakage testing

    SciTech Connect

    Kronberg, J.W.

    1995-02-14

    An apparatus is described for use in one-hundred percent leak testing of food containers used in conjunction with a tracer gas. The apparatus includes a shell with entrance and exit air locks to create a controlled atmosphere through which a series of containers is conveyed by a conveyor belt. The pressure in the shell is kept lower than the pressure in the containers and the atmosphere is made to flow with the containers so that a tracer gas placed in the packages before sealing them will leak more readily, but the leaked tracer gas will remain associated with the leaking package as it moves through the shell. The leaks are detected with a sniffer probe in fluid communication with a gas chromatograph. The gas chromatograph issues a signal when it detects a leak to an ejector that will eject the leaking container from the conveyor. The system is timed so that the series of containers can move continuously into and out of the shell, past the probe and the ejector, without stopping, yet each package is tested for leaks and removed if leaking. 3 figs.

  9. Field testing method for photovaltaic modules

    NASA Astrophysics Data System (ADS)

    Ramos, Gerber N.

    For remote areas, where solar photovoltaic modules are the only source of power, it is essential to perform preventive maintenance to insure that the PV system works properly; unfortunately, prices for PV testers range from 1,700 to 8,000. To address this issue, a portable inexpensive tester and analysis methodology have been developed. Assembling a simple tester, which costs $530 and weighs about 5 pounds, and using the Four-Parameters PV Model, we characterized the current-voltage (I-V) curve at environmental testing conditions; and then employing radiation, temperature, and age degradation sensitivity equations, we extrapolated the I-V curve to standard testing conditions. After applying the methodology to three kinds of silicon modules (mono-crystalline, multi-crystalline, and thin-film), we obtained maximum power points up to 97% of the manufacturer's specifications. Therefore, based on these results, it is reasonably accurate and affordable to verify the performance of solar modules in the field.

  10. Method and apparatus for container leakage testing

    DOEpatents

    Kronberg, James W.

    1995-01-01

    An apparatus for use in one-hundred percent leak testing of food containers used in conjunction with a tracer gas. The apparatus includes a shell with entrance and exit air locks to create a controlled atmosphere through which a series of containers is conveyed by a conveyor belt. The pressure in the shell is kept lower than the pressure in the containers and the atmosphere is made to flow with the containers so that a tracer gas placed in the packages before sealing them will leak more readily, but the leaked tracer gas will remain associated with the leaking package as it moves through the shell. The leaks are detected with a sniffer probe in fluid communication with a gas chromatograph. The gas chromatograph issues a signal when it detects a leak to an ejector that will eject the leaking container from the conveyor. The system is timed so that the series of containers can move continuously into and out of the shell, past the probe and the ejector, without stopping, yet each package is tested for leaks and removed if leaking.

  11. Reservoir Exploration/Testing by Elastomechanical Methods

    SciTech Connect

    Bodvarsson, Gunnar

    1980-12-18

    The purpose of this brief note is to present a preliminary evaluation of the potential of the elastomechanical methods in practical reservoir engineering and related areas. Assuming simple relevant situations, the strength of the field signals will be estimated and compared to other ground surface data such as gravity and D.C. electrical signals that are also of interest in reservoir monitoring. Because of greater difficulty in observing surface strain, we will limit our discussion to vertical ground displacement and tilt signals.

  12. Alunite dissolution rates: Dissolution mechanisms and implications for Mars

    NASA Astrophysics Data System (ADS)

    Miller, J. L.; Elwood Madden, A. S.; Phillips-Lander, C. M.; Pritchett, B. N.; Elwood Madden, M. E.

    2016-01-01

    Alunite (KAl3(SO4)2(OH)6) is a hydrated aluminous sulfate mineral associated with acidic, oxidizing aqueous environments on Earth. Additionally, orbiting spacecraft and rovers on Mars have reported spectral data that indicate a range of mono- and polyhydrated sulfate phases and hydroxysulfate phases, suggesting such conditions also existed on Mars in the past. This study examines alunite dissolution rates in aqueous systems with varying pH, temperature, and solution chemistry conditions. Alunite dissolution rates in dilute solutions are 2-3 orders of magnitude slower than jarosite dissolution rates measured under analogous conditions. Similar to jarosite, alunite dissolution rates vary as a function of activity of H+ and OH- following the rate law log r (mol m-2 s-1) = -0.133(±0.02)pH - 10.65(±0.07) at pH < 5 and log r = 0.194(±0.04)pH - 12.53(±0.26) at pH > 5. However, minimum alunite dissolution rates are shifted to higher pH (5-5.5), likely due to differences in Fe and Al speciation. Alunite and jarosite rates converge in saturated NaCl and CaCl2 brines as the activity of water decreases, suggesting that differences in water exchange rates with Fe3+ and Al3+ control dissolution rates in dilute solutions, while metal-Cl- complexation occurs at similar rates within the brines. Particle lifetimes based on measured dissolution rates in dilute solutions show that alunite particles are expected to be preserved two orders of magnitude longer than jarosite particles over a range of pH and temperature conditions. In particular, alunite is more likely to be preserved in neutral to moderately alkaline systems compared to jarosite, which is expected to be preserved in more acidic conditions. Alunite dissolution produced amorphous Al-rich alteration products at moderate to high pH. Unlike jarosite, alunite dissolution does not show a clear trend as a function of temperature; alunite dissolution rates do not increase with increasing temperature, likely due to lower

  13. Toward Biopredictive Dissolution for Enteric Coated Dosage Forms.

    PubMed

    Al-Gousous, J; Amidon, G L; Langguth, P

    2016-06-01

    The aim of this work was to develop a phosphate buffer based dissolution method for enteric-coated formulations with improved biopredictivity for fasted conditions. Two commercially available enteric-coated aspirin products were used as model formulations (Aspirin Protect 300 mg, and Walgreens Aspirin 325 mg). The disintegration performance of these products in a physiological 8 mM pH 6.5 bicarbonate buffer (representing the conditions in the proximal small intestine) was used as a standard to optimize the employed phosphate buffer molarity. To account for the fact that a pH and buffer molarity gradient exists along the small intestine, the introduction of such a gradient was proposed for products with prolonged lag times (when it leads to a release lower than 75% in the first hour post acid stage) in the proposed buffer. This would allow the method also to predict the performance of later-disintegrating products. Dissolution performance using the accordingly developed method was compared to that observed when using two well-established dissolution methods: the United States Pharmacopeia (USP) method and blank fasted state simulated intestinal fluid (FaSSIF). The resulting dissolution profiles were convoluted using GastroPlus software to obtain predicted pharmacokinetic profiles. A pharmacokinetic study on healthy human volunteers was performed to evaluate the predictions made by the different dissolution setups. The novel method provided the best prediction, by a relatively wide margin, for the difference between the lag times of the two tested formulations, indicating its being able to predict the post gastric emptying onset of drug release with reasonable accuracy. Both the new and the blank FaSSIF methods showed potential for establishing in vitro-in vivo correlation (IVIVC) concerning the prediction of Cmax and AUC0-24 (prediction errors not more than 20%). However, these predictions are strongly affected by the highly variable first pass metabolism

  14. Non-destructive testing method and apparatus

    DOEpatents

    Akers, Douglas W.

    2011-10-04

    Non-destructive testing apparatus may comprise a photon source and a source material that emits positrons in response to bombardment of the source material with photons. The source material is positionable adjacent the photon source and a specimen so that when the source material is positioned adjacent the photon source it is exposed to photons produced thereby. When the source material is positioned adjacent the specimen, the specimen is exposed to at least some of the positrons emitted by the source material. A detector system positioned adjacent the specimen detects annihilation gamma rays emitted by the specimen. Another embodiment comprises a neutron source and a source material that emits positrons in response to neutron bombardment.

  15. 40 CFR 61.164 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... following methods in appendix A to 40 CFR part 60: (A) Method 1 for sample and velocity traverse. (B) Method... furnace. (ii) Use the following methods in appendix A to 40 CFR part 60: (A) Method 1 for sample and... Arsenic Emissions From Glass Manufacturing Plants § 61.164 Test methods and procedures. (a) To...

  16. Eddy Current Method for Fatigue Testing

    NASA Technical Reports Server (NTRS)

    Simpson, John W. (Inventor); Fulton, James P. (Inventor); Wincheski, Russell A. (Inventor); Todhunter, Ronald G. (Inventor); Namkung, Min (Inventor); Nath, Shridhar C. (Inventor)

    1997-01-01

    Flux-focusing electromagnetic sensor using a ferromagnetic flux-focusing lens simplifies inspections and increases detectability of fatigue cracks and material loss in high conductivity material. A ferrous shield isolates a high-turn pick-up coil from an excitation coil. Use of the magnetic shield produces a null voltage output across the receiving coil in presence of an unflawed sample. Redistribution of the current flow in the sample caused by the presence of flaws. eliminates the shielding condition and a large output voltage is produced, yielding a clear unambiguous flaw signal. Maximum sensor output is obtained when positioned symmetrically above the crack. By obtaining position of maximum sensor output, it is possible to track the fault and locate the area surrounding its tip. Accuracy of tip location is enhanced by two unique features of the sensor; a very high signal-to-noise ratio of the probe's output resulting in an extremely smooth signal peak across the fault, and a rapidly decaying sensor output outside a small area surrounding the crack tip enabling the search region to be clearly defined. Under low frequency operation, material thinning due to corrosion causes incomplete shielding of the pick-up coil. Low frequency output voltage of the probe is therefore a direct indicator of thickness of the test sample. Fatigue testing a conductive material is accomplished by applying load to the material, applying current to the sensor, scanning the material with the sensor, monitoring the sensor output signal, adjusting material load based on the sensor output signal of the sensor, and adjusting position of the sensor based on its output signal.

  17. In situ dissolution analysis using coherent anti-Stokes Raman scattering (CARS) and hyperspectral CARS microscopy.

    PubMed

    Fussell, Andrew; Garbacik, Erik; Offerhaus, Herman; Kleinebudde, Peter; Strachan, Clare

    2013-11-01

    The solid-state form of an active pharmaceutical ingredient (API) in an oral dosage form plays an important role in determining the dissolution rate of the API. As the solid-state form can change during dissolution, there is a need to monitor the oral dosage form during dissolution testing. Coherent anti-Stokes Raman scattering (CARS) microscopy provides rapid, spectrally selective imaging to monitor the oral dosage form during dissolution. In this study, in situ CARS microscopy was combined with inline UV absorption spectroscopy to monitor the solid-state change in oral dosage forms containing theophylline anhydrate undergoing dissolution and to correlate the solid-state change with a change in dissolution rate. The results from in situ CARS microscopy showed that theophylline anhydrate converted to theophylline monohydrate during dissolution resulting in a reduction in the dissolution rate. The addition of methyl cellulose to the dissolution medium was found to delay the theophylline monohydrate growth and changed the morphology of the monohydrate. The net effect was an increased dissolution rate for theophylline anhydrate. Our results show that in situ CARS microscopy combined with inline UV absorption spectroscopy is capable of monitoring oral dosage forms undergoing dissolution and correlating changes in solid-state form with changes in dissolution rate. PMID:23994672

  18. Uranium-Molybdenum Dissolution Flowsheet Studies

    SciTech Connect

    Pierce, R. A.

    2007-03-01

    The Super Kukla (SK) Prompt Burst Reactor operated at the Nevada Test Site from 1964 to 1978. The SK material is a uranium-molybdenum (U-Mo) alloy material of 90% U/10% Mo by weight at approximately 20% 235U enrichment. H-Canyon Engineering (HCE) requested that the Savannah River National Lab (SRNL) define a flowsheet for safely and efficiently dissolving the SK material. The objective is to dissolve the material in nitric acid (HNO3) in the H-Canyon dissolvers to a U concentration of 15-20 g/L (3-4 g/L 235U) without the formation of precipitates or the generation of a flammable gas mixture. Testing with SK material validated the applicability of dissolution and solubility data reported in the literature for various U and U-Mo metals. Based on the data, the SK material can be dissolved in boiling 3.0-6.0 M HNO3 to a U concentration of 15-20 g/L and a corresponding Mo concentration of 1.7-2.2 g/L. The optimum flowsheet will use 4.0-5.0 M HNO3 for the starting acid. Any nickel (Ni) cladding associated with the material will dissolve readily. After dissolution is complete, traditional solvent extraction flowsheets can be used to recover and purify the U. Dissolution rates for the SK material are consistent with those reported in the literature and are adequate for H-Canyon processing. When the SK material dissolved at 70-100 o C in 1-6 M HNO3, the reaction bubbled vigorously and released nitrogen oxide (NO) and nitrogen dioxide (NO2) gas. Gas generation tests in 1 M and 2 M HNO3 at 100 o C generated less than 0.1 volume percent hydrogen (H2) gas. It is known that higher HNO3 concentrations are less favorable for H2 production. All tests at 70-100 o C produced sufficient gas to mix the solutions without external agitation. At room temperature in 5 M HNO3, the U-Mo dissolved slowly and the U-laden solution sank to the bottom of the dissolution vessel because of its greater density. The effect of the density difference insures that the SK material cannot dissolve and

  19. DISSOLUTION OF ZIRCONIUM AND ALLOYS THEREFOR

    DOEpatents

    Swanson, J.L.

    1961-07-11

    The dissolution of zirconium cladding in a water solution of ammonium fluoride and ammonium nitrate is described. The method finds particular utility in processing spent fuel elements for nuclear reactors. The zirconium cladding is first dissolved in a water solution of ammonium fluoride and ammonium nitrate; insoluble uranium and plutonium fiuorides formed by attack of the solvent on the fuel materiai of the fuel element are then separated from the solution, and the fuel materiai is dissolved in another solution.

  20. Enhanced test methods to characterise automotive battery cells

    NASA Astrophysics Data System (ADS)

    Mulder, Grietus; Omar, Noshin; Pauwels, Stijn; Leemans, Filip; Verbrugge, Bavo; De Nijs, Wouter; Van den Bossche, Peter; Six, Daan; Van Mierlo, Joeri

    This article evaluates the methods to characterise the behaviour of lithium ion cells of several chemistries and a nickel metal hydride cell for automotive applications like (plug-in) hybrid vehicles and battery electric vehicles. Although existing characterisation test methods are used, it was also indicated to combine test methods in order to speed up the test time and to create an improved comparability of the test results. Also, the existing capacity tests ignore that cells can be charged at several current rates. However, this is of interest for, e.g. fast charging and regenerative braking. Tests for high power and high energy application have been integrated in the enhanced method. The article explains the rationale to ameliorate the test methods. The test plan should make it possible to make an initial division in a group of cells purchased from several suppliers.

  1. Comparison of modal test methods on the Voyager payload

    NASA Technical Reports Server (NTRS)

    Hanks, B. R.; Miserentino, R.; Ibrahim, S. R.; Lee, S. H.; Wada, B. K.

    1978-01-01

    A comparison of the performance of modern modal data analysis methods on test data from the Voyager Jupiter/Saturn payload is presented. Four different test/data-analysis combinations are compared - multiple-point sine excitation tests, single-point random-excitation tests using two different techniques of manipulating Fourier transform data, and a time-domain method for analyzing random data. Results indicate that all four methods can give comparable results. Of the four, the time-domain approach detects more modes in the test data and, at the same time, shows the greatest promise for reducing the time and cost of modal testing.

  2. 40 CFR 60.123 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 7 2012-07-01 2012-07-01 false Test methods and procedures. 60.123 Section 60.123 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Smelters § 60.123 Test methods and procedures. (a) In conducting the performance tests required in §...

  3. 40 CFR 60.123 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Test methods and procedures. 60.123 Section 60.123 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Smelters § 60.123 Test methods and procedures. (a) In conducting the performance tests required in §...

  4. 40 CFR 60.123 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Test methods and procedures. 60.123 Section 60.123 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Smelters § 60.123 Test methods and procedures. (a) In conducting the performance tests required in §...

  5. A new test method for young age strength of shotcrete

    SciTech Connect

    Teramoto, Shozo

    1995-12-31

    As a method for testing the young-age strength of shotcrete used as tunnel supports, use of the Parotester, which is designed to measure the hardness of paper rolls at printing factories, has been considered. This paper reports the results of laboratory tests conducted to establish this method as a means of strength testing.

  6. Visual relevance of display image quality testing by photometric methods

    NASA Astrophysics Data System (ADS)

    Andren, Boerje; Breidne, Magnus; Hansson, L. A.; Persson, Bo

    1993-09-01

    The two major international test methods for evaluation of the image quality of video display terminals are the ISO 9241-3 international standard and the MPR test. In this paper we make an attempt to compare the visual relevance of these two test methods.

  7. A Residual Mass Ballistic Testing Method to Compare Armor Materials or Components (Residual Mass Ballistic Testing Method)

    SciTech Connect

    Benjamin Langhorst; Thomas M Lillo; Henry S Chu

    2014-05-01

    A statistics based ballistic test method is presented for use when comparing multiple groups of test articles of unknown relative ballistic perforation resistance. The method is intended to be more efficient than many traditional methods for research and development testing. To establish the validity of the method, it is employed in this study to compare test groups of known relative ballistic performance. Multiple groups of test articles were perforated using consistent projectiles and impact conditions. Test groups were made of rolled homogeneous armor (RHA) plates and differed in thickness. After perforation, each residual projectile was captured behind the target and its mass was measured. The residual masses measured for each test group were analyzed to provide ballistic performance rankings with associated confidence levels. When compared to traditional V50 methods, the residual mass (RM) method was found to require fewer test events and be more tolerant of variations in impact conditions.

  8. Integrated Data Collection Analysis (IDCA) Program - SSST Testing Methods

    SciTech Connect

    Sandstrom, Mary M.; Brown, Geoffrey W.; Preston, Daniel N.; Pollard, Colin J.; Warner, Kirstin F.; Remmers, Daniel L.; Sorensen, Daniel N.; Whinnery, LeRoy L.; Phillips, Jason J.; Shelley, Timothy J.; Reyes, Jose A.; Hsu, Peter C.; Reynolds, John G.

    2013-03-25

    The Integrated Data Collection Analysis (IDCA) program is conducting a proficiency study for Small- Scale Safety and Thermal (SSST) testing of homemade explosives (HMEs). Described here are the methods used for impact, friction, electrostatic discharge, and differential scanning calorimetry analysis during the IDCA program. These methods changed throughout the Proficiency Test and the reasons for these changes are documented in this report. The most significant modifications in standard testing methods are: 1) including one specified sandpaper in impact testing among all the participants, 2) diversifying liquid test methods for selected participants, and 3) including sealed sample holders for thermal testing by at least one participant. This effort, funded by the Department of Homeland Security (DHS), is putting the issues of safe handling of these materials in perspective with standard military explosives. The study is adding SSST testing results for a broad suite of different HMEs to the literature. Ultimately the study will suggest new guidelines and methods and possibly establish the SSST testing accuracies needed to develop safe handling practices for HMEs. Each participating testing laboratory uses identical test materials and preparation methods wherever possible. The testing performers involved are Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Indian Head Division, Naval Surface Warfare Center, (NSWC IHD), Sandia National Laboratories (SNL), and Air Force Research Laboratory (AFRL/RXQL). These tests are conducted as a proficiency study in order to establish some consistency in test protocols, procedures, and experiments and to compare results when these testing variables cannot be made consistent.

  9. The Influence of Pressure on the Intrinsic Dissolution Rate of Amorphous Indomethacin

    PubMed Central

    Löbmann, Korbinian; Flouda, Konstantina; Qiu, Danwen; Tsolakou, Theodosia; Wang, Wenbo; Rades, Thomas

    2014-01-01

    New drug candidates increasingly tend to be poorly water soluble. One approach to increase their solubility is to convert the crystalline form of a drug into the amorphous form. Intrinsic dissolution testing is an efficient standard method to determine the intrinsic dissolution rate (IDR) of a drug and to test the potential dissolution advantage of the amorphous form. However, neither the United States Pharmacopeia (USP) nor the European Pharmacopeia (Ph.Eur) state specific limitations for the compression pressure in order to obtain compacts for the IDR determination. In this study, the influence of different compression pressures on the IDR was determined from powder compacts of amorphous (ball-milling) indomethacin (IND), a glass solution of IND and poly(vinylpyrrolidone) (PVP) and crystalline IND. Solid state properties were analyzed with X-ray powder diffraction (XRPD) and the final compacts were visually observed to study the effects of compaction pressure on their surface properties. It was found that there is no significant correlation between IDR and compression pressure for crystalline IND and IND–PVP. This was in line with the observation of similar surface properties of the compacts. However, compression pressure had an impact on the IDR of pure amorphous IND compacts. Above a critical compression pressure, amorphous particles sintered to form a single compact with dissolution properties similar to quench-cooled disc and crystalline IND compacts. In such a case, the apparent dissolution advantage of the amorphous form might be underestimated. It is thus suggested that for a reasonable interpretation of the IDR, surface properties of the different analyzed samples should be investigated and for amorphous samples the IDR should be measured also as a function of the compression pressure used to prepare the solid sample for IDR testing. PMID:25140536

  10. Standard test method for size of anthracite

    SciTech Connect

    Not Available

    1980-01-01

    This method covering screen analysis of anthracite is used to determine the percentage of undersize or oversize in ny given commercial size. The values stated in inch-pound units are to be regarded as the standard. Procedure, in case th coal is wet, air-dryit before screening. Determine the undersize first. For broken, egg, and stove sizes, up-end each piece by hand on the screen, to determine whether in any position it passes through the screen. For nut, pea, buckwheat, and rice sizes, shake the screens gently with a reciprocating horizontal motion, so as to avoid breakage ofthe coal, until practically no more coal will pass through the openings. Screen the coal in such increments as will allow the pieces to be in direct contact with the screen openings after the completion of the shaking of each increment.

  11. Methods of testing parameterizations: Vertical ocean mixing

    NASA Technical Reports Server (NTRS)

    Tziperman, Eli

    1992-01-01

    The ocean's velocity field is characterized by an exceptional variety of scales. While the small-scale oceanic turbulence responsible for the vertical mixing in the ocean is of scales a few centimeters and smaller, the oceanic general circulation is characterized by horizontal scales of thousands of kilometers. In oceanic general circulation models that are typically run today, the vertical structure of the ocean is represented by a few tens of discrete grid points. Such models cannot explicitly model the small-scale mixing processes, and must, therefore, find ways to parameterize them in terms of the larger-scale fields. Finding a parameterization that is both reliable and plausible to use in ocean models is not a simple task. Vertical mixing in the ocean is the combined result of many complex processes, and, in fact, mixing is one of the less known and less understood aspects of the oceanic circulation. In present models of the oceanic circulation, the many complex processes responsible for vertical mixing are often parameterized in an oversimplified manner. Yet, finding an adequate parameterization of vertical ocean mixing is crucial to the successful application of ocean models to climate studies. The results of general circulation models for quantities that are of particular interest to climate studies, such as the meridional heat flux carried by the ocean, are quite sensitive to the strength of the vertical mixing. We try to examine the difficulties in choosing an appropriate vertical mixing parameterization, and the methods that are available for validating different parameterizations by comparing model results to oceanographic data. First, some of the physical processes responsible for vertically mixing the ocean are briefly mentioned, and some possible approaches to the parameterization of these processes in oceanographic general circulation models are described in the following section. We then discuss the role of the vertical mixing in the physics of the

  12. Methods for the Joint Meta-Analysis of Multiple Tests

    ERIC Educational Resources Information Center

    Trikalinos, Thomas A.; Hoaglin, David C.; Small, Kevin M.; Terrin, Norma; Schmid, Christopher H.

    2014-01-01

    Existing methods for meta-analysis of diagnostic test accuracy focus primarily on a single index test. We propose models for the joint meta-analysis of studies comparing multiple index tests on the same participants in paired designs. These models respect the grouping of data by studies, account for the within-study correlation between the tests'…

  13. 7 CFR 58.930 - Official test methods.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Procedures § 58.930 Official test methods. (a) Chemical. Chemical analysis, except where otherwise prescribed... of Analysis of the AOAC or by the latest edition of Standard Methods for the Examination of Dairy... 7 Agriculture 3 2011-01-01 2011-01-01 false Official test methods. 58.930 Section...

  14. 7 CFR 58.930 - Official test methods.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Procedures § 58.930 Official test methods. (a) Chemical. Chemical analysis, except where otherwise prescribed... of Analysis of the AOAC or by the latest edition of Standard Methods for the Examination of Dairy... 7 Agriculture 3 2010-01-01 2010-01-01 false Official test methods. 58.930 Section...

  15. 40 CFR 60.386 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Processing Plants § 60.386 Test methods and procedures. (a) In conducting the performance tests required in... holder of Method 5 may be operated without heaters if the gas stream being sampled is at ambient temperature. For gas streams above ambient temperature, the Method 5 sampling train shall be operated with...

  16. A New Method for Incremental Testing of Finite State Machines

    NASA Technical Reports Server (NTRS)

    Pedrosa, Lehilton Lelis Chaves; Moura, Arnaldo Vieira

    2010-01-01

    The automatic generation of test cases is an important issue for conformance testing of several critical systems. We present a new method for the derivation of test suites when the specification is modeled as a combined Finite State Machine (FSM). A combined FSM is obtained conjoining previously tested submachines with newly added states. This new concept is used to describe a fault model suitable for incremental testing of new systems, or for retesting modified implementations. For this fault model, only the newly added or modified states need to be tested, thereby considerably reducing the size of the test suites. The new method is a generalization of the well-known W-method and the G-method, but is scalable, and so it can be used to test FSMs with an arbitrarily large number of states.

  17. ASTM test methods for composite characterization and evaluation

    NASA Technical Reports Server (NTRS)

    Masters, John E.

    1994-01-01

    A discussion of the American Society for Testing and Materials is given. Under the topic of composite materials characterization and evaluation, general industry practice and test methods for textile composites are presented.

  18. 40 CFR 60.344 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Manufacturing Plants § 60.344 Test methods and procedures. (a) In conducting the performance tests required in... the average pressure loss of the gas stream through the scrubber and the average scrubbing...

  19. Overview of Non-Volatile Testing and Screening Methods

    NASA Technical Reports Server (NTRS)

    Irom, Farokh

    2001-01-01

    Testing methods for memories and non-volatile memories have become increasingly sophisticated as they become denser and more complex. High frequency and faster rewrite times as well as smaller feature sizes have led to many testing challenges. This paper outlines several testing issues posed by novel memories and approaches to testing for radiation and reliability effects. We discuss methods for measurements of Total Ionizing Dose (TID).

  20. On the effects of subsurface parameters on evaporite dissolution (Switzerland)

    NASA Astrophysics Data System (ADS)

    Zidane, Ali; Zechner, Eric; Huggenberger, Peter; Younes, Anis

    2014-05-01

    Uncontrolled subsurface evaporite dissolution could lead to hazards such as land subsidence. Observed subsidences in a study area of Northwestern Switzerland were mainly due to subsurface dissolution (subrosion) of evaporites such as halite and gypsum. A set of 2D density driven flow simulations were evaluated along 1000 m long and 150 m deep 2D cross sections within the study area that is characterized by tectonic horst and graben structures. The simulations were conducted to study the effect of the different subsurface parameters that could affect the dissolution process. The heterogeneity of normal faults and its impact on the dissolution of evaporites is studied by considering several permeable faults that include non-permeable areas. The mixed finite element method (MFE) is used to solve the flow equation, coupled with the multipoint flux approximation (MPFA) and the discontinuous Galerkin method (DG) to solve the diffusion and the advection parts of the transport equation.

  1. Comparison of HEPA filter test methods in corrosive environments

    SciTech Connect

    Murphy, L.P.; Fernandez, S.J.; Motes, B.G.

    1980-07-01

    An evaluation of the three HEPA filter test methods in corrosive environments was conducted: the dioctyl phthalate (DOP) method (US Standard Method ANSI N-101.1-1972), the sodium chloride method (British Standard 3928:1969), and the soda-fluorescein or uranine method (French Standard AFNOR STD NFX 44-011). The effects of humidity, temperature and oxides of nitrogen (NO/sub x/) on each method was examined. The experimental design used in the evaluation measured and separated both the effect of each variable and any interaction between variables on the test method. Recommendations for changes in the standard methods to reduce erratic online results are presented.

  2. Effects of Surface Composition on the Aerosolisation and Dissolution of Inhaled Antibiotic Combination Powders Consisting of Colistin and Rifampicin.

    PubMed

    Wang, Wenbo; Zhou, Qi Tony; Sun, Si-Ping; Denman, John A; Gengenbach, Thomas R; Barraud, Nicolas; Rice, Scott A; Li, Jian; Yang, Mingshi; Chan, Hak-Kim

    2016-03-01

    Colistin is often the only effective antibiotic against the respiratory infections caused by multidrug-resistant Gram-negative bacteria. However, colistin-resistant multidrug-resistant isolates have been increasingly reported and combination therapy is preferred to combat resistance. In this study, five combination formulations containing colistin (COL) and rifampicin (RIF) were prepared by spray drying. The lowest minimum inhibitory concentration (MIC) value against Pseudomonas aeruginosa PAO1 was measured for the formulation of COL/RIF = 4:1 with relatively high emitted doses (over 80%) and satisfactory fine particle fractions (over 60%). Data from X-ray photoelectron spectroscopy (XPS) and nano-time-of-flight secondary ion mass spectrometry (ToF-SIMS) showed the surfaces of particles were mainly covered by rifampicin even for the formulation with a mass ratio of COL/RIF = 4:1. Because colistin is hygroscopic and rifampicin is hydrophobic, moisture absorption of combination formulations was significantly lower than the pure colistin formulation in the dynamic vapour sorption results. To investigate the dissolution characteristics, four dissolution test methods (diffusion Franz cell, modified Franz cell, flow-through and beaker methods) were employed and compared. The modified Franz cell method was selected to test the dissolution behaviour of aerosolised powder formulations to eliminate the effect of membrane on dissolution. The results showed that surface enrichment of hydrophobic rifampicin neither affected aerosolisation nor retarded dissolution rate of colistin in the combination formulations. For the first time, advanced surface characterisation techniques of XPS and ToF-SIMS have shown their capability to understand the effect of surface composition on the aerosolisation and dissolution of combination powders.

  3. A Method of Partly Automated Testing of Software

    NASA Technical Reports Server (NTRS)

    Lowry, Mike; Visser, Willem; Washington, Rich; Artho, Cyrille; Goldberg, Allen; Haveland, Klaus; Pasareanu, Corina; Khurshid, Sarfraz; Roflu, Grigore

    2007-01-01

    A method of automated testing of software has been developed that provides an alternative to the conventional mostly manual approach for software testing. The method combines (1) automated generation of test cases on the basis of systematic exploration of the input domain of the software to be tested with (2) run-time analysis in which execution traces are monitored, verified against temporal-logic specifications, and analyzed by concurrency-error-detection algorithms. In this new method, the user only needs to provide the temporal logic specifications against which the software will be tested and the abstract description of the input domain.

  4. Status and applications of echinoid (phylum echinodermata) toxicity test methods

    SciTech Connect

    Bay, S.; Burgess, R.; Nacci, D.

    1993-01-01

    The use of echinoderms for toxicity testing has focused primarily on sea urchins and sand dollars (Strongylocentrotus purpuratus, Arbacia punctulata, Lytechinus pictus, and Dendraster excentricus, for example). The status and relative sensitivity of various test methods are described. The most frequently used test methods consist of short-term exposures of sea urchin sperm or embryos; these tests can be easily conducted at all times of the year by using species with complementary spawning cycles or laboratory conditioned populations of a single species. Data from reference toxicant and effluent toxicity tests are summarized. Information on the precision and sensitivity of echinoid test methods are limited and preclude rigorous comparisons with other test methods. The available data indicate that the sensitivity and precision of these methods are comparable to short-term chronic methods for other marine invertebrates and fish. Recent application of the sperm test in toxicity identification evaluations (TIEs) and studies of effluent toxicity decay and sediment toxicity illustrate the versatility of this rapid (10 to 60 min exposure) test method. Embryo tests typically use a 48 to 96 h exposure period and measure the occurrence of embryo malformations. Most recent applications of the embryo test have been for the assessment of sediment elutriate toxicity. Adult echinoderms are not frequently used to assess effluent or receiving water toxicity. Recent studies have had success in using the adult life stage of urchins and sand dollars to assess the effects of contaminated sediment on growth, behavior, and bioaccumulation.

  5. Ergodicity test of the eddy correlation method

    NASA Astrophysics Data System (ADS)

    Chen, J.; Hu, Y.; Yu, Y.; Lü, S.

    2014-07-01

    for the ensemble average, a large rate of error would occur with use of the eddy correction method due to losing the low frequency component information of the larger vortex. When the multi-station observation was compared with the single-station observation, the wide sense of stationary random process originating from the multi-station observation expanded from a vortex which was about 1000 m smaller than a boundary layer scale to the turbulent vortex, which was larger than the boundary layer scale of 2000 m. Therefore, the calculation of the turbulence average or variance and turbulent flux could effectively meet the ergodic assumption, and the results would be approximate to the actual values. Regardless of vertical velocity and temperature, if the ergodic stationary random processes could be met, then the variance of the vortexes in the different temporal scales could follow M-O similarity theory; in the case of the non-ergodic random process, its vortex variance deviated from the M-O similarity relations. The exploration of ergodicity in the atmospheric turbulence measurements is doubtlessly helpful to understanding the issues in atmospheric turbulent flux observation, and provides a theoretical basis for overcoming related difficulties.

  6. Evaluation of new aquatic toxicity test methods for oil dispersants

    SciTech Connect

    Pace, C.B.; Clark, J.R.; Bragin, G.E.

    1994-12-31

    Current aquatic toxicity test methods used for dispersant registration do not address real world exposure scenarios. Current test methods require 48 or 96 hour constant exposure conditions. In contrast, environmentally realistic exposures can be described as a pulse in which the initial concentration declines over time. Recent research using a specially designed testing apparatus (the California system) has demonstrated that exposure to Corexit 9527{reg_sign} under pulsed exposure conditions may be 3 to 22 times less toxic compared to continuous exposure scenarios. The objectives of this study were to compare results of toxicity tests using the California test system to results from standardized tests, evaluate sensitivity of regional (Holmesimysis cast and Atherinops affinis) vs. standard test species (Mysidopsis bahia and Menidia beryllina) and determine if tests using the California test system and method are reproducible. All tests were conducted using Corexit 9527{reg_sign} as the test material. Standard toxicity tests conducted with M. bahia and H. cast resulted in LC50s similar to those from tests using the California apparatus. LC50s from tests conducted in the authors` laboratory with the California system and standard test species were within a factor of 2 to 6 of data previously reported for west coast species. Results of tests conducted with H. cast in the laboratory compared favorably to data reported by Singer et al. 1991.

  7. Saltcake Dissolution FY 2002 Status Report

    SciTech Connect

    HERTING, D.L.

    2002-09-26

    Laboratory tests were completed on the dissolution characteristics of Hanford saltcake waste from single-shell waste tanks 241-B-109 and 241-SX-101 (henceforth referred to as B-109 and SX-101). The River Protection Project (RPP) is tasked with retrieving waste from double-shell and single-shell tanks to provide feed for vitrification. The RPP organization needs chemical and physical data to evaluate technologies for retrieving the waste. Little relevant laboratory testing has been done to evaluate in-tank dissolution parameters for the various types of saltcake wastes that exist in single-shell tanks. A computer modeling program known as the Environmental Simulation Program (ESP), produced by OLI Systems, Inc. of Morris Plains, New Jersey, is being used by the RPP organization to predict solubilities during dilution and retrieval of all tank waste types. Data from this task are provided to ESP users to support evaluation, refinement, and validation of the ESP model. Cascade (or ''stepwise'') dissolution tests were performed on composite saltcake samples from both tanks. The purpose of these tests is to evaluate the solid/liquid phase distribution of chemicals and radionuclides during tank waste retrieval operations. Solid phase identification tests were also performed on saltcake from both tanks. Weight percent (wt%) dilution is defined in this report as 100 times the weight of diluent (water or 2 M NaOH solution) divided by the weight of undiluted saltcake composite sample. A 50% dilution, for example, would be 50 g of H{sub 2}O (or 50 g of 2 M NaOH) added to 100 g of undiluted composite sample. Volume percent (Vol%) dilution is defined as 100 times the volume of diluent divided by the calculated volume of undiluted sample. Weight percent dilutions are measured directly by weighing the undiluted sample and diluent. Volume percent dilutions are estimated from the known volume of diluent and calculated volume of undiluted sample.

  8. Test methods and design allowables for fibrous composites. Volume 2

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C. (Editor)

    1989-01-01

    Topics discussed include extreme/hostile environment testing, establishing design allowables, and property/behavior specific testing. Papers are presented on environmental effects on the high strain rate properties of graphite/epoxy composite, the low-temperature performance of short-fiber reinforced thermoplastics, the abrasive wear behavior of unidirectional and woven graphite fiber/PEEK, test methods for determining design allowables for fiber reinforced composites, and statistical methods for calculating material allowables for MIL-HDBK-17. Attention is also given to a test method to measure the response of composite materials under reversed cyclic loads, a through-the-thickness strength specimen for composites, the use of torsion tubes to measure in-plane shear properties of filament-wound composites, the influlence of test fixture design on the Iosipescu shear test for fiber composite materials, and a method for monitoring in-plane shear modulus in fatigue testing of composites.

  9. Biorelevant dissolution media as a predictive tool for glyburide a class II drug.

    PubMed

    Wei, Hai; Löbenberg, Raimar

    2006-09-01

    The purpose of this study was to predict the oral absorption of glyburide. Biorelevant dissolution methods, combined with permeability measurements and computational simulations, were used to predict the oral absorption of glyburide. The objective was to establish in vitro/in vivo correlations (IVIVCs) based on the biopharmaceutics drug classification system. The solubility of the glyburide powder was measured in different media. The dissolution behavior of two commercial tablet formulations was tested in different media. Two chemical grades of sodium taurocholate: low quality (LQ)=crude and high quality (HQ)=97% purity, and egg-lecithin: LQ=60% and HQ=99.1% purity were used to prepare fasted state small intestinal fluid (FaSSIF). Simulated intestinal fluid (SIF) and blank FaSSIF without lecithin and taurocholate (BL-FaSSIF) were used as controls. The dissolution tests were performed under constant pH and dynamic pH conditions. The dynamic pH range from 5.0 to 7.5 simulated the biological pH range of gastrointestinal (GI) tract in the fasted state. The drug permeability was studied using Caco-2 cell line. The predictions of the fraction dose absorbed were performed using GastroPlustrade mark. The results of the simulations were compared with actual clinical data taken from a bioequivalence study. The solubility of glyburide was highest in LQ-FaSSIF. The two tablet formulations had significantly different dissolution behaviors in LQ-FaSSIF. The in vitro data was used as the input function into a simulation software. The dynamic LQ-FaSSIF dissolution data achieved the best prediction of the average AUC and C(max) of the clinically observed data. The present study shows that BCS based parameters combined with software simulations can be used to establish an IVIVC for glyburide. In vitro/in silico tools can potentially be used as surrogate for bioequivalence studies.

  10. Evaluation criteria and test methods for electrochromic windows

    SciTech Connect

    Czanderna, A.W. ); Lampert, C.M. )

    1990-07-01

    Report summarizes the test methods used for evaluating electrochromic (EC) windows, and summarizes what is known about degradation of their performance, and recommends methods and procedures for advancing EC windows for buildings applications. 77 refs., 13 figs., 6 tabs.

  11. Outlier Measures and Norming Methods for Computerized Adaptive Tests.

    ERIC Educational Resources Information Center

    Bradlow, Eric T.; Weiss, Robert E.

    2001-01-01

    Compares four methods that map outlier statistics to a familiarity probability scale (a "P" value). Explored these methods in the context of computerized adaptive test data from a 1995 nationally administered computerized examination for professionals in the medical industry. (SLD)

  12. 40 CFR 60.446 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Sensitive Tape and Label Surface Coating Operations § 60.446 Test methods and procedures. (a) The VOC... the web substrate. (b) Method 25 shall be used to determine the VOC concentration, in parts...

  13. 40 CFR 60.446 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Sensitive Tape and Label Surface Coating Operations § 60.446 Test methods and procedures. (a) The VOC... the web substrate. (b) Method 25 shall be used to determine the VOC concentration, in parts...

  14. 40 CFR 60.446 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Sensitive Tape and Label Surface Coating Operations § 60.446 Test methods and procedures. (a) The VOC... the web substrate. (b) Method 25 shall be used to determine the VOC concentration, in parts...

  15. Recommendations for Developing Alternative Test Methods for Developmental Neurotoxicity

    EPA Science Inventory

    There is great interest in developing alternative methods for developmental neurotoxicity testing (DNT) that are cost-efficient, use fewer animals and are based on current scientific knowledge of the developing nervous system. Alternative methods will require demonstration of the...

  16. Susceptibility testing of anaerobic bacteria: myth, magic, or method?

    PubMed Central

    Wexler, H M

    1991-01-01

    The demand for susceptibility testing of anaerobes has increased, yet consensus as to procedure and interpretation in this area has not been achieved. While routine testing of anaerobic isolates is not needed, certain isolates in specific clinical settings should be tested. Also, laboratories may monitor their local antibiograms by doing periodic surveillance batch testing. The National Committee for Clinical Laboratory Standards has published a protocol of methods approved for susceptibility testing of anaerobic bacteria. Both agar and broth microdilution are included; however, the broth disk elution method is no longer approved by the National Committee for Clinical Laboratory Standards because of method-related interpretive errors. A number of newer methods are undergoing evaluation and seem promising. Clinicians and microbiologists reviewing susceptibility reports should be aware of sources of variability in the test results. Variables in susceptibility testing of anaerobes include the media and methods used, organisms chosen for testing, breakpoints chosen for interpretation, antibiotic, and determination of endpoint. Clustering of MICs around the breakpoint may lead to significant variability in test results. Adherence of testing laboratories to approved methods and careful descriptions of the method and the breakpoints used for interpretation would facilitate interlaboratory comparisons and allow problems of emerging resistance to be noted. A variety of resistance mechanisms occurs in anaerobic bacteria, including the production of beta-lactamase and other drug-inactivating enzymes, alteration of target proteins, and inability of the drug to penetrate the bacterial wall. Antimicrobial resistance patterns in the United States and abroad are described. PMID:1747863

  17. Harmonization of standard toxicity test methods used in North America

    SciTech Connect

    Ingersoll, C.G.; Dwyer, F.J.; Ankley, G.T.

    1995-12-31

    Over the past two years, Environment Canada (EC) and the US Environmental Protection Agency (EPA) have developed standard methods for conducting toxicity and bioaccumulation tests with freshwater, estuarine, and marine sediments. Existing ASTM methods were used as a basis to harmonize these methods for conducting testing with either field-collected or laboratory-spiked sediments. For freshwater toxicity tests, methods are described by EC and EPA for the amphipod Hyalella azteca and the midges Chironomus tentans and C. riparius. Endpoints include 10- to 14-d survival of growth. Methods are also described by EPA for conducting 28-d bioaccumulation tests with the oligochaete Lumbriculus variegatus. For estuarine and marine toxicity tests, methods are described for several amphipods (i.e., Rhepoxynius abronius, Ampelisca abdita, Eohaustorius estuarius, Leptocheirus plumulosus). Endpoints include 10-d survival and reburial. EC is also developing methods for conducting toxicity tests with Atlantic, Pacific, and Arctic Canadian species of polychaetes. Methods are described by EPA for conducting 28-d bioaccumulation tests with a variety of mollusks (i.e., Macoma spp.) and polychaetes (i.e., Nereis spp.). Slight inconsistencies in methods between freshwater and estuarine/marine testing or between EC and EPA testing include: (1) static vs. flow-through conditions, (2) sieving of sediment, (3) types and quantity of food, (4) age of test organisms, or (4) duration of the test and required endpoints. Additional research is in progress to: (1) develop chronic toxicity tests with amphipods and midges measuring survival, growth, or reproduction, (2) develop whole-sediment toxicity identification evaluation (TIE) procedures, (3) refine sediment spiking procedures, and (4) field-validate laboratory tests.

  18. Electric vehicle chassis dynamometer test methods at JPL and their correlation to track tests

    NASA Technical Reports Server (NTRS)

    Marte, J.; Bryant, J.

    1983-01-01

    Early in its electric vehicle (EV) test program, JPL recognized that EV test procedures were too vague and too loosely defined to permit much meaningful data to be obtained from the testing. Therefore, JPL adopted more stringent test procedures and chose the chassis dynamometer rather than the track as its principal test technique. Through the years, test procedures continued to evolve towards a methodology based on chassis dynamometers which would exhibit good correlation with track testing. Based on comparative dynamometer and track test results on the ETV-1 vehicle, the test methods discussed in this report demonstrate a means by which excellent track-to-dynamometer correlation can be obtained.

  19. 40 CFR 63.786 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CFR part 60, appendix A, is the definitive method for determining the VOC content of coatings, as... source may use batch formulation data as a test method in lieu of Method 24 of appendix A to 40 CFR part..., in the event of conflicting results, Method 24 of appendix A of 40 CFR part 60 shall take...

  20. 40 CFR 63.786 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CFR part 60, appendix A, is the definitive method for determining the VOC content of coatings, as... source may use batch formulation data as a test method in lieu of Method 24 of appendix A to 40 CFR part..., in the event of conflicting results, Method 24 of appendix A of 40 CFR part 60 shall take...

  1. 40 CFR 63.786 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR part 60, appendix A, is the definitive method for determining the VOC content of coatings, as... source may use batch formulation data as a test method in lieu of Method 24 of appendix A to 40 CFR part..., in the event of conflicting results, Method 24 of appendix A of 40 CFR part 60 shall take...

  2. 40 CFR 63.786 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CFR part 60, appendix A, is the definitive method for determining the VOC content of coatings, as... source may use batch formulation data as a test method in lieu of Method 24 of appendix A to 40 CFR part..., in the event of conflicting results, Method 24 of appendix A of 40 CFR part 60 shall take...

  3. 40 CFR 63.786 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CFR part 60, appendix A, is the definitive method for determining the VOC content of coatings, as... source may use batch formulation data as a test method in lieu of Method 24 of appendix A to 40 CFR part..., in the event of conflicting results, Method 24 of appendix A of 40 CFR part 60 shall take...

  4. Investigating Item Exposure Control Methods in Computerized Adaptive Testing

    ERIC Educational Resources Information Center

    Ozturk, Nagihan Boztunc; Dogan, Nuri

    2015-01-01

    This study aims to investigate the effects of item exposure control methods on measurement precision and on test security under various item selection methods and item pool characteristics. In this study, the Randomesque (with item group sizes of 5 and 10), Sympson-Hetter, and Fade-Away methods were used as item exposure control methods. Moreover,…

  5. Unravelling the relationship between degree of disorder and the dissolution behavior of milled glibenclamide.

    PubMed

    Mah, Pei T; Laaksonen, Timo; Rades, Thomas; Aaltonen, Jaakko; Peltonen, Leena; Strachan, Clare J

    2014-01-01

    Milling is an attractive method to prepare amorphous formulations as it does not require the use of solvents and is suitable for thermolabile drugs. One of the key critical quality attributes of milled amorphous formulations is their dissolution behavior. However, there are limited studies that have investigated the relationship between degree of disorder induced by milling and dissolution behavior. The main aim of this study was to identify the analytical technique used to characterize degree of disorder that correlates best with the recrystallization behavior during dissolution of milled glibenclamide samples. Solid state and surface changes during dissolution of milled glibenclamide samples were monitored in order to elucidate the processes that influence the dissolution behavior of milled glibenclamide samples. Glibenclamide was ball milled for different durations and analyzed using X-ray powder diffractometry (XRPD), Raman spectroscopy and differential scanning calorimetry (DSC). Recrystallization during dissolution of the milled amorphous materials was investigated using an in situ Raman setup. SEM was used to monitor the surfaces of the compacts during dissolution. XRPD, Raman spectroscopy and DSC indicated that glibenclamide was fully amorphous after milling for 30, 60, and 120 min, respectively. 'DSC amorphous' (i.e. fully amorphous according to the onset of crystallization obtained from DSC) glibenclamide samples experienced negligible recrystallization which had no effect on the dissolution profiles. Samples that were not 'DSC amorphous' experienced recrystallization which resulted in a decrease in dissolution rate. Unexpected elevated dissolution rate was observed initially during dissolution for samples milled for 15 to 45 min, and this was related to particle loss from surfaces of the disks during dissolution. In conclusion, the onset of crystallization obtained from DSC best predicts the recrystallization of glibenclamide during dissolution

  6. Coamorphous repaglinide-saccharin with enhanced dissolution.

    PubMed

    Gao, Yuan; Liao, Jiao; Qi, Xuan; Zhang, Jianjun

    2013-06-25

    Recently, coamorphous systems composed of two drugs or a drug and a small molecule excipient, gained interests due to their ability in overcoming limitations associated with solid dispersions. In this study, coamorphous form of repaglinide (REP), a BCS class II anti-diabetic drug with low aqueous solubility and high permeability was achieved with saccharin (SAC) by solution crystallization and characterized. An accurate and precise HPLC method was established for the simultaneous determination of REP and SAC. Coamorphous REP-SAC with 1:1 stoichiometry had unique thermal behavior, obvious FTIR shifts and the absence of sharp diffraction peak, suggesting the formation of a coamorphous material and interaction of REP with SAC through hydrogen bonds formed between REP's secondary amine and SAC's carbonyl group. Coamorphous REP-SAC showed great improvement in solubility and dissolution under sink conditions in various media. In addition, it was conformed in supersaturated dissolution of coamorphous REP-SAC in distilled water that the coamorphous material had remarkably longer time length for REP to be remained at a supersaturated concentration and had better metastable solubility. This coamorphous system provides a feasible way to process drugs with low solubility into substances with enhanced dissolution and stabilized amorphous state that could be conducive to greater bioavailability than the crystalline drug.

  7. Novel methods to study the effect of protein content and dissolution temperature on the solubility of milk protein concentrate: Focused beam reflectance and ultrasonic flaw detector-based methods.

    PubMed

    Hauser, M; Amamcharla, J K

    2016-05-01

    Processing, storage, dissolution conditions, and the composition of milk protein concentrates (MPC) affect the solubility of high-protein dairy powders. Increasing the storage temperature and time decrease the solubility of MPC and milk protein isolates (MPI). The MPC and MPI are popular ingredients in high-protein food products and have a variety of protein contents. In addition, the dissolution temperature has been shown to affect the solubility of the powders. This study focused on determining how protein content and dissolution temperature affect the solubility of MPC and MPI. For this study, 11 powders were obtained from a commercial manufacturer. The powders were classified as A, B, C, and D, and they had a mean protein content of 85, 87, 88, and 90%, respectively. A 5% (wt/wt) concentration of powder was dissolved in water at 40 and 48°C. The solubility of the MPC and MPI samples were characterized using an ultrasonic flaw detector (UFD) and focused beam reflectance measurement (FBRM). The UFD and FBRM data were collected every 15 and 10 s, respectively, for 1,800 s. At both dissolution temperatures, the UFD and FBRM data showed that the solubility decreased as the protein content increased. Powders A and B were found to be more soluble because they had a lower relative velocity standard deviation, high area under the attenuation curve, high peak height, and low peak time. With the FBRM, the fine and medium particle count decreased and large particle count increased as the protein content increased. Powders dissolved at 48°C typically had a lower relative velocity standard deviation, higher area under the attenuation curve, higher peak height, and lower peak time than the powders dissolved at 40°C. The FBRM showed that powders dissolved at 48°C reached a stable counts before the powders dissolved at 40°C. Overall, the study showed that increasing the protein content led to a reduction in solubility and increasing the dissolution temperature improved the

  8. Novel methods to study the effect of protein content and dissolution temperature on the solubility of milk protein concentrate: Focused beam reflectance and ultrasonic flaw detector-based methods.

    PubMed

    Hauser, M; Amamcharla, J K

    2016-05-01

    Processing, storage, dissolution conditions, and the composition of milk protein concentrates (MPC) affect the solubility of high-protein dairy powders. Increasing the storage temperature and time decrease the solubility of MPC and milk protein isolates (MPI). The MPC and MPI are popular ingredients in high-protein food products and have a variety of protein contents. In addition, the dissolution temperature has been shown to affect the solubility of the powders. This study focused on determining how protein content and dissolution temperature affect the solubility of MPC and MPI. For this study, 11 powders were obtained from a commercial manufacturer. The powders were classified as A, B, C, and D, and they had a mean protein content of 85, 87, 88, and 90%, respectively. A 5% (wt/wt) concentration of powder was dissolved in water at 40 and 48°C. The solubility of the MPC and MPI samples were characterized using an ultrasonic flaw detector (UFD) and focused beam reflectance measurement (FBRM). The UFD and FBRM data were collected every 15 and 10 s, respectively, for 1,800 s. At both dissolution temperatures, the UFD and FBRM data showed that the solubility decreased as the protein content increased. Powders A and B were found to be more soluble because they had a lower relative velocity standard deviation, high area under the attenuation curve, high peak height, and low peak time. With the FBRM, the fine and medium particle count decreased and large particle count increased as the protein content increased. Powders dissolved at 48°C typically had a lower relative velocity standard deviation, higher area under the attenuation curve, higher peak height, and lower peak time than the powders dissolved at 40°C. The FBRM showed that powders dissolved at 48°C reached a stable counts before the powders dissolved at 40°C. Overall, the study showed that increasing the protein content led to a reduction in solubility and increasing the dissolution temperature improved the

  9. Dissolution kinetics and etch pit studies of potassium aluminium sulphate

    NASA Astrophysics Data System (ADS)

    van der Hoek, B.; Van Enckevort, W. J. P.; Van Der Linden, W. H.

    1983-03-01

    The dissolution process of the {111} faces of potash alum is studied, both by microtopographic examinations of the etch pit patterns and by measurement of the dissolution kinetics in a rotating disc crystallizer. Both methods showed that the Cabrera-Levine dissolution theory holds for the two most common dislocation types ending on the {111} faces of potash alum. On the basis of the rotating disc experiments, the interfacial supersaturation of the etch pit experiments was roughly estimated. Using this, it was found that at interfacial supersaturations below -0.6% (dislocations with <110> Burgers vector) or below -0.85% (dislocations with <100> Burgers vector) numerous etch pits related to those dislocation types appeared. Below those undersaturations the dissolution process is mainly determined by volume diffusion. From the critical undersaturation, determined in the rotating disc crystallizer, the value of the edge free energy of a step was found to be approximately 0.01 J/m 2.

  10. 49 CFR 230.45 - Method of testing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.45 Method of testing. Steam gauges shall be compared with an accurate test gauge or dead weight tester. While under test load at the MAWP of the boiler to which the gauge will be...

  11. 49 CFR 230.45 - Method of testing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.45 Method of testing. Steam gauges shall be compared with an accurate test gauge or dead weight tester. While under test load at the MAWP of the boiler to which the gauge will be...

  12. 49 CFR 230.45 - Method of testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.45 Method of testing. Steam gauges shall be compared with an accurate test gauge or dead weight tester. While under test load at the MAWP of the boiler to which the gauge will be...

  13. 49 CFR 230.45 - Method of testing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.45 Method of testing. Steam gauges shall be compared with an accurate test gauge or dead weight tester. While under test load at the MAWP of the boiler to which the gauge will be...

  14. 49 CFR 230.45 - Method of testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Steam Gauges § 230.45 Method of testing. Steam gauges shall be compared with an accurate test gauge or dead weight tester. While under test load at the MAWP of the boiler to which the gauge will be...

  15. 16 CFR 1610.3 - Summary of test method.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... FOR THE FLAMMABILITY OF CLOTHING TEXTILES The Standard § 1610.3 Summary of test method. The Standard provides methods of testing the flammability of textiles from or intended to be used for apparel; establishes three classes of flammability; sets forth the requirements for classifying textiles; and...

  16. 40 CFR 63.365 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... exhaust continuously during the first evacuation using the procedure found in 40 CFR part 60, appendix A... outlined in the test methods listed in paragraph (b) of this section. (B) Test Method 18 or 25A, 40 CFR... concentration required in § 63.364(e), follow the procedures in PS 8 or PS 9 in 40 CFR part 60, appendix...

  17. 40 CFR 60.34c - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 6 2011-07-01 2011-07-01 false Test methods and procedures. 60.34c Section 60.34c Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Municipal Solid Waste Landfills § 60.34c Test methods and procedures. For approval, a State plan...

  18. 40 CFR 63.323 - Test methods and monitoring.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 10 2013-07-01 2013-07-01 false Test methods and monitoring. 63.323... Perchloroethylene Air Emission Standards for Dry Cleaning Facilities § 63.323 Test methods and monitoring. (a) When... exhaust of the carbon adsorber weekly with a colorimetric detector tube or PCE gas analyzer....

  19. 40 CFR 76.15 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 17 2014-07-01 2014-07-01 false Test methods and procedures. 76.15 Section 76.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.15 Test methods and procedures. (a)...

  20. 40 CFR 76.15 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 16 2011-07-01 2011-07-01 false Test methods and procedures. 76.15 Section 76.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.15 Test methods and procedures. (a)...

  1. 40 CFR 76.15 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 17 2012-07-01 2012-07-01 false Test methods and procedures. 76.15 Section 76.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.15 Test methods and procedures. (a)...

  2. 40 CFR 76.15 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Test methods and procedures. 76.15 Section 76.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.15 Test methods and procedures. (a)...

  3. 40 CFR 76.15 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 17 2013-07-01 2013-07-01 false Test methods and procedures. 76.15 Section 76.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) ACID RAIN NITROGEN OXIDES EMISSION REDUCTION PROGRAM § 76.15 Test methods and procedures. (a)...

  4. 16 CFR 1509.6 - Component-spacing test method.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Component-spacing test method. 1509.6 Section 1509.6 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR NON-FULL-SIZE BABY CRIBS § 1509.6 Component-spacing test method. The apex of...

  5. 16 CFR 1509.6 - Component-spacing test method.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Component-spacing test method. 1509.6 Section 1509.6 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION FEDERAL HAZARDOUS SUBSTANCES ACT REGULATIONS REQUIREMENTS FOR NON-FULL-SIZE BABY CRIBS § 1509.6 Component-spacing test method. The apex of...

  6. 40 CFR 61.304 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... performance test according to Method 22 of appendix A of 40 CFR part 60 shall be performed to determine... (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Transfer Operations § 61.304 Test methods and procedures. (a) The procedures...

  7. 40 CFR 61.304 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... performance test according to Method 22 of appendix A of 40 CFR part 60 shall be performed to determine... (CONTINUED) NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Benzene Emissions From Benzene Transfer Operations § 61.304 Test methods and procedures. (a) The procedures...

  8. A Cluster-Based Method for Test Construction.

    ERIC Educational Resources Information Center

    Boekkooi-Timminga, Ellen

    1990-01-01

    A new test construction model based on the Rasch model is proposed. This model, the cluster-based method, considers groups of interchangeable items rather than individual items and uses integer programing. Results for six test construction problems indicate that the method produces accurate results in small amounts of time. (SLD)

  9. Testing and Validation of the Dynamic Interia Measurement Method

    NASA Technical Reports Server (NTRS)

    Chin, Alexander; Herrera, Claudia; Spivey, Natalie; Fladung, William; Cloutier, David

    2015-01-01

    This presentation describes the DIM method and how it measures the inertia properties of an object by analyzing the frequency response functions measured during a ground vibration test (GVT). The DIM method has been in development at the University of Cincinnati and has shown success on a variety of small scale test articles. The NASA AFRC version was modified for larger applications.

  10. 40 CFR 60.74 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 7 2014-07-01 2014-07-01 false Test methods and procedures. 60.74 Section 60.74 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Nitric Acid Plants § 60.74 Test methods and procedures. (a)...

  11. Improved method of HIPOT testing of advanced ignition system product

    SciTech Connect

    Baker, P.C.

    1992-04-01

    A new method of high potential (HIPOT) testing of advanced ignition system (AIS) product was developed. The new incorporated using a silver-filled RTV silicone as the electrodes of the HIPOT tester instead of the preformed, semi-rigid aluminum electrodes of the current tester. Initial results indicate that the developed method was more sensitive to the testing requirements of the HIPOT test. A patent for the combination of the material used and the method of testing developed was attempted but was withdrawn following a patent search by the US Patent Office.

  12. Method and apparatus for globally-accessible automated testing

    DOEpatents

    Layne, Scott P.; Beugelsdijk, Tony J.

    1998-01-01

    A method and apparatus for sharing integrated testing services with a plurality of autonomous remote clients is disclosed. In the disclosed method, in response to an access request message, a process controller transmits an access enabling message to the remote client. The access enabling message includes instructions performable by a remote client to generate test equipment commands. A process controller interprets and transforms these commands into automated test instrument suite commands, which are provided to laboratory modules to perform the indicated tests. Test data results are then obtained and transmitted to the remote client.

  13. Nondestructive testing methods for 55-gallon, waste storage drums

    SciTech Connect

    Ferris, R.H.; Hildebrand, B.P.; Hockey, R.L.; Riechers, D.M.; Spanner, J.C.; Duncan, D.R.

    1993-06-01

    The Westinghouse Hanford Company (WHC) authorized Pacific Northwest Laboratory (PNL) to conduct a feasibility study to identify promising nondestructive testing (NDT) methods for detecting general and localized (both pitting and pinhole) corrosion in the 55-gal drums that are used to store solid waste materials at the Hanford Site. This document presents results obtained during a literature survey, identifies the relevant reference materials that were reviewed, provides a technical description of the methods that were evaluated, describes the laboratory tests that were conducted and their results, identifies the most promising candidate methods along with the rationale for these selections, and includes a work plan for recommended follow-on activities. This report contains a brief overview and technical description for each of the following NDT methods: magnetic testing techniques; eddy current testing; shearography; ultrasonic testing; radiographic computed tomography; thermography; and leak testing with acoustic detection.

  14. Boehmite Dissolution Studies Supporting High Level Waste Pretreatment - 9383

    SciTech Connect

    Peterson, Reid A.; Russell, Renee L.; Snow, Lanee A.

    2009-03-01

    Boehmite is present in significant quantities in several of the Hanford waste tanks. It has been proposed that the boehmite will be dissolved through caustic leaching in the Hanford Waste Treatment Plant currently under construction. Therefore, it is important to fully understand the nature of this dissolution so that the process can be deployed. This research determined the impact of primary control parameters on the boehmite dissolution rate. The impact of aluminate ion on the dissolution kinetics was determined. In addition, other parameters that impact boehmite dissolution, such as free hydroxide concentration and reaction temperature, were also assessed and used to develop a semi-empirical model of the boehmite dissolution process. The understanding derived from this work will be used as the basis to evaluate and improve the planned performance of the Hanford Waste Treatment plant. This work is the first in a series of programs aimed at demonstrating the Waste Treatment Plant dissolution process. This work will be used to develop a simulant of the boehmite-containing Hanford waste. That simulant will then be used in laboratory- and pilot-scale testing to demonstrate the Waste Treatment Plant pretreatment process in an integrated fashion.

  15. Enhanced CO2 Dissolution in Heterogeneous Porous Media

    NASA Astrophysics Data System (ADS)

    Daniels, K.; Neufeld, J. A.; Bickle, M. J.; Hallworth, M. A.

    2014-12-01

    Long-term and secure geological storage of CO2 through technologies such as Carbon Capture and Storage (CCS) within reservoirs is seen as a technological means to reduce anthropogenic CO2 emissions. The long-term viability of this technology is reliant on the structural and secondary trapping of supercritical CO2 within heterogeneous reservoirs. Secondary trapping, primarily through the dissolution of CO2 into ambient reservoir brine to produce a denser fluid, is capable of retaining CO2 in the subsurface and thus reducing the risks of storage. To model secondary trapping we need to understand how the flow of CO2 through heterogeneous reservoir rocks enhances dissolution of supercritical CO2 in reservoir brines. Here we experimentally investigate the dissolution of CO2 in reservoir brines in layered, heterogeneous geological formations. Using analogue experiments, designed to approximate an enhanced oil recovery (EOR) setting, the processes of mixing, dispersion and dissolution are examined. These are compared against test results from non-layered, homogeneous porous media experiments. We find that heterogeneities significantly enhance mixing, particularly between adjacent porous layers. During fluid propagation, pore-scale viscous fingers grow and retreat, thereby providing an increased surface area between the flow and the ambient reservoir fluid. This enhanced mixing is predicted to substantially increase the dissolution of CO2 in reservoir brines. Both permeability and viscosity differences are found to have a significant effect on the interface between the two fluids, and therefore the likely amount of dissolution of CO2.

  16. The Iosipescu shear test method as used for testing polymers and composite materials

    NASA Technical Reports Server (NTRS)

    Adams, Donald F.

    1990-01-01

    This paper describes a shear test method for polymers and composite materials, based on the Iosipescu (1967) shear test which was originally developed for use with homogeneous isotropic metals. Special attention is given to the loading fixture for the test, the standard specimen design and shear stress measurements. The range of the test applications is indicated. The method is in the final stages of being accepted as an ASTM standard.

  17. Simulation of in vitro dissolution behavior using DDDPlus™.

    PubMed

    Almukainzi, May; Okumu, Arthur; Wei, Hai; Löbenberg, Raimar

    2015-02-01

    Dissolution testing is a performance test for many dosage forms including tablets and capsules. The objective of this study was to evaluate if computer simulations can predict the in vitro dissolution of two model drugs for which different dissolution data were available. Published montelukast sodium and glyburide dissolution data was used for the simulations. Different pharmacopeial and biorelevant buffers, volumes, and rotations speeds were evaluated. Additionally, a pH change protocol was evaluated using these buffers. DDDPlus™ 3, Beta version (Simulation Plus, Inc.), was used to simulate the in vitro dissolution data. The simulated data were compared with the in vitro data. A regression coefficient between predicted and observed data was used to assess the simulations. The statistical analysis of Montelukast sodium showed that there was a significant correlation between the in vitro release data and the predicted data for all cases except for one buffer. For glyburide, there was also a significant correlation between the experimental data and the predicted data using single pH conditions. Using the dynamic pH protocol, a correlation was significant for one biorelevant media. The simulations showed that both in vitro drug releases were sensitive to solubility effects which confirmed their BCS class II category. Computer simulations of the in vitro release using DDDPlus™ have the potential to estimate the in vivo dissolution at an early stage in the drug development process. This might be used to choose the most appropriate dissolution condition to establish IVIVC and to develop biorelevant in vitro performance tests to capture critical product attributes for quality control procedures in quality by design environments. PMID:25409918

  18. Dissolution rates of coals and graphite in Fe-C-S melts in direct ironmaking: Dependence of carbon dissolution rate on carbon structure

    SciTech Connect

    Wu, C.; Sahajwalla, V.

    2000-02-01

    It is commonly recognized that the rates of carbon dissolution from graphite as compared to that from glassy carbon are very different, although they are similar in composition and density. Previous studies have established that the liquid-side mass-transfer rate limitation mechanism could not account for the carbon dissolution from nongraphite carbon sources. It has been assumed that the carbon structure affects its dissolution rate in molten iron. In many in-bath direct smelting processes such as HISMELT, predicting the carbon dissolution rate of coals prior to their use in a smelting bath is crucial. In order to verify the relationship between the carbon dissolution rate and the structure of coals, carbon dissolution experiments were conducted in an induction to furnace using the carburizer cover method.

  19. 40 CFR Appendix Ix to Part 268 - Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B)

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 28 2013-07-01 2013-07-01 false Extraction Procedure (EP) Toxicity Test Method and Structural Integrity Test (Method 1310B) IX Appendix IX to Part 268 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) SOLID WASTES (CONTINUED) LAND DISPOSAL RESTRICTIONS...

  20. Marital dissolution: an economic analysis.

    PubMed

    Hunter, K A

    1984-01-01

    A longitudinal analysis of factors affecting marital dissolution in the United States is presented using data from the Coleman-Rossi Retrospective Life History. Factors considered include labor force participation of both spouses, wage growth, size of family unit, age at marriage, and educational status. The study is based on the economic analysis approach developed by Gary S. Becker and others.

  1. Formulations for iron oxides dissolution

    DOEpatents

    Horwitz, Earl P.; Chiarizia, Renato

    1992-01-01

    A mixture of a di- or polyphosphonic acid and a reductant wherein each is present in a sufficient amount to provide a synergistic effect with respect to the dissolution of metal oxides and optionally containing corrosion inhibitors and pH adjusting agents.

  2. 40 CFR 63.945 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) The test shall be conducted in accordance with the procedures specified in Method 21 of 40 CFR part 60... criteria of Method 21 of 40 CFR part 60, appendix A, except the instrument response factor criteria in... shall be calibrated before use on each day of its use by the procedures specified in Method 21 of 40...

  3. 40 CFR 60.725 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Surface Coating: Surface Coating of Plastic Parts for Business Machines § 60.725 Test methods and... of each coating as received. (2) For Method 24, the sample must be at least a 1-liter sample in a 1-liter container. (b) Other methods may be used to determine the VOC content of each coating if...

  4. 40 CFR 60.725 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Surface Coating: Surface Coating of Plastic Parts for Business Machines § 60.725 Test methods and... of each coating as received. (2) For Method 24, the sample must be at least a 1-liter sample in a 1-liter container. (b) Other methods may be used to determine the VOC content of each coating if...

  5. 40 CFR 75.22 - Reference test methods.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... volumetric flow. (3) Methods 3, 3A, or 3B are the reference methods for the determination of the dry... are produced in accordance with method 205 in Appendix M of 40 CFR Part 51; (ii) The sampling point... emissions from stationary gas turbines for testing under appendix E to this part. (7) ASTM...

  6. 40 CFR 60.547 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... sampling times or smaller volumes, when necessitated by process variables or other factors, may be approved... of any test by Method 25. For Method 25, the sampling time for each of three runs shall be at least 1 hour. Method 1 shall be used to select the sampling site, and the sampling point shall be the...

  7. 40 CFR 60.547 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sampling times or smaller volumes, when necessitated by process variables or other factors, may be approved... of any test by Method 25. For Method 25, the sampling time for each of three runs shall be at least 1 hour. Method 1 shall be used to select the sampling site, and the sampling point shall be the...

  8. 40 CFR 63.945 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...) The test shall be conducted in accordance with the procedures specified in Method 21 of 40 CFR part 60... criteria of Method 21 of 40 CFR part 60, appendix A, except the instrument response factor criteria in section 3.1.2(a) of Method 21 shall be for the average composition of the organic constituents in...

  9. 40 CFR 63.945 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) The test shall be conducted in accordance with the procedures specified in Method 21 of 40 CFR part 60... criteria of Method 21 of 40 CFR part 60, appendix A, except the instrument response factor criteria in section 3.1.2(a) of Method 21 shall be for the average composition of the organic constituents in...

  10. 40 CFR 63.1046 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) National Emission Standards for Oil-Water Separators and Organic-Water Separators § 63.1046 Test methods... Method 21 of 40 CFR part 60, appendix A. Each potential leak interface (i.e., a location where organic... instrument shall meet the performance criteria of Method 21 of 40 CFR part 60, appendix A, except...

  11. 40 CFR 63.1046 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) National Emission Standards for Oil-Water Separators and Organic-Water Separators § 63.1046 Test methods... Method 21 of 40 CFR part 60, appendix A. Each potential leak interface (i.e., a location where organic... instrument shall meet the performance criteria of Method 21 of 40 CFR part 60, appendix A, except...

  12. Test method to measure resistance towards fragmentation by studded tires

    NASA Astrophysics Data System (ADS)

    Viman, L.

    1995-01-01

    In the Nordic countries most cars are equipped with studded tires during the winter. The studs increase the wear on the road surfaces and a special test method has been developed to measure the aggregates' resistance towards fragmentation by studded tires. The method has proven to correlate very well with the actual wear on the road surfaces. The Nordic countries Sweden, Norway and Finland have agreed to propose this method as a European Standard test method. One reason is to be able to set requirements on aggregates to be used in countries where studded tires are allowed. A cross-testing project regarding this Nordic abrasion test for studded tires was set up in order to determine the repeatability and the reproducibility of the methods to become European Standard.

  13. Accelerated Test Method for Corrosion Protective Coatings Project

    NASA Technical Reports Server (NTRS)

    Falker, John; Zeitlin, Nancy; Calle, Luz

    2015-01-01

    This project seeks to develop a new accelerated corrosion test method that predicts the long-term corrosion protection performance of spaceport structure coatings as accurately and reliably as current long-term atmospheric exposure tests. This new accelerated test method will shorten the time needed to evaluate the corrosion protection performance of coatings for NASA's critical ground support structures. Lifetime prediction for spaceport structure coatings has a 5-year qualification cycle using atmospheric exposure. Current accelerated corrosion tests often provide false positives and negatives for coating performance, do not correlate to atmospheric corrosion exposure results, and do not correlate with atmospheric exposure timescales for lifetime prediction.

  14. Fire test method for graphite fiber reinforced plastics

    NASA Technical Reports Server (NTRS)

    Bowles, K. J.

    1980-01-01

    A potential problem in the use of graphite fiber reinforced resin matrix composites is the dispersal of graphite fibers during accidental fires. Airborne, electrically conductive fibers originating from the burning composites could enter and cause shorting in electrical equipment located in surrounding areas. A test method for assessing the burning characteristics of graphite fiber reinforced composites and the effectiveness of the composites in retaining the graphite fibers has been developed. The method utilizes a modified Ohio State University Rate of Heat Release apparatus. The equipment and the testing procedure are described. The application of the test method to the assessment of composite materials is illustrated for two resin matrix/graphite composite systems.

  15. Residual flexibility test method for verification of constrained structural models

    NASA Technical Reports Server (NTRS)

    Admire, John R.; Tinker, Michael L.; Ivey, Edward W.

    1992-01-01

    A method is presented for deriving constrained modes and frequencies from a model correlated to a set of free-free test modes and a set of measured residual flexibilities. The method involves a simple modification of the MacNeal and Rubin component mode representation to allow verification of a constrained structural model. Results for two spaceflight structures show quick convergence of constrained modes using an easily measurable set of free-free modes plus the residual flexibility matrix or its boundary partition. This paper further validates the residual flexibility approach as an alternative test/analysis method when fixed-base testing proves impractical.

  16. BSAC standardized disc susceptibility testing method (version 11).

    PubMed

    Howe, R A; Andrews, J M

    2012-12-01

    This article highlights key amendments incorporated into version 11 of the BSAC standardized disc susceptibility testing method, available as Supplementary data at JAC Online (http://jac.oxfordjournals.org/) and on the BSAC web site (http://bsac.org.uk/susceptibility/guidelines-standardized-disc-susceptibility-testing-method/). The basic disc susceptibility testing method remains unchanged, but there have been a number of alterations to the interpretive criteria for certain organism/drug combinations due to continuing harmonization with the EUCAST MIC breakpoints and constant efforts to improve the reliability and clinical applicability of the guidance.

  17. Fire test method for graphite fiber reinforced plastics

    NASA Technical Reports Server (NTRS)

    Bowles, K. J.

    1980-01-01

    A potential problem in the use of graphite fiber reinforced resin matrix composites is the dispersal of graphite fibers during accidential fires. Airborne, electrically conductive fibers originating from the burning composites could enter and cause shorting in electrical equipment located in surrounding areas. A test method for assessing the burning characteristics of graphite fiber reinforced composites and the effectiveness of the composites in retaining the graphite fibers has been developed. The method utilizes a modified rate of heat release apparatus. The equipment and the testing procedure are described. The application of the test method to the assessment of composite materials is illustrated for two resin matrix/graphite composite systems.

  18. Dissolution curve comparisons through the F(2) parameter, a Bayesian extension of the f(2) statistic.

    PubMed

    Novick, Steven; Shen, Yan; Yang, Harry; Peterson, John; LeBlond, Dave; Altan, Stan

    2015-01-01

    Dissolution (or in vitro release) studies constitute an important aspect of pharmaceutical drug development. One important use of such studies is for justifying a biowaiver for post-approval changes which requires establishing equivalence between the new and old product. We propose a statistically rigorous modeling approach for this purpose based on the estimation of what we refer to as the F2 parameter, an extension of the commonly used f2 statistic. A Bayesian test procedure is proposed in relation to a set of composite hypotheses that capture the similarity requirement on the absolute mean differences between test and reference dissolution profiles. Several examples are provided to illustrate the application. Results of our simulation study comparing the performance of f2 and the proposed method show that our Bayesian approach is comparable to or in many cases superior to the f2 statistic as a decision rule. Further useful extensions of the method, such as the use of continuous-time dissolution modeling, are considered.

  19. Template occluded SBA-15: An effective dissolution enhancer for poorly water-soluble drug

    NASA Astrophysics Data System (ADS)

    Tingming, Fu; Liwei, Guo; Kang, Le; Tianyao, Wang; Jin, Lu

    2010-09-01

    The aim of the present work was to improve the dissolution rate of piroxicam by inclusion into template occluded SBA-15. Our strategy involves directly introducing piroxicam into as-prepared SBA-15 occluded with P123 (EO 20PO 70EO 20) by self assembling method in acetonitrile/methylene chloride mixture solution. Ultraviolet spectrometry experiment and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) profiles show that the piroxicam and P123 contents in the inclusion compound are 12 wt% and 28 wt%, respectively. X-ray powder diffraction and DSC analysis reveal that the included piroxicam is arranged in amorphous form. N 2 adsorption-desorption experiment indicates that the piroxicam has been introduced to the mesopores instead of precipitating at the outside of the silica material. The inclusion compound was submitted to in vitro dissolution tests, the results show that the piroxicam dissolve from template occluded inclusion compound more rapidly, than these from the piroxicam crystalline and template removed samples in all tested conditions. Thus a facile method to improve the dissolution rate of poorly water-soluble drug was established, and this discovery opens a new avenue for the utilization of templates used for the synthesis of mesoporous materials.

  20. Stoichiometry of smectite dissolution reaction

    NASA Astrophysics Data System (ADS)

    Metz, Volker; Amram, Keren; Ganor, Jiwchar

    2005-04-01

    The dissolution stoichiometry of smectite-rich bentonites SAz-1, STx-1 and SWy-1 was studied at 50°C and pH 2 and 3 using flow-through reactors. In addition to smectite, these samples contain considerable amounts of silica phases (quartz, cristobalite and/or amorphous silica). As a result, the molar Al/Si ratios of the bulk samples are significantly lower than those of the pure smectite. Smectite dissolution was highly incongruent during the first few hundred to few thousand hours of the experiments. Release rates of Si, Mg, Ca and Na underwent a distinct transition from an initial period of rapid release to significantly lower release rate at steady state. A reversed trend was observed for release of Al, which gradually increased from very low starting release rate to higher release rate at steady state. At steady state the ratio of released Al to released Si was found to be constant and independent of the experimental conditions. We suggest that this ratio represents the Al/Si ratio of the smectite itself, and it is not influenced by the presence of accessory phases in the sample. The rapid release of calcium, sodium and magnesium from the interlayer sites is explained by ion-exchange reactions, whereas the fast release of silicon is explained by dissolution of amorphous silica. We interpret the initial slow release of Al as the result of inhibition of smectite dissolution due to coating or cementation of the smectite aggregates by amorphous silica. As the silica is dissolved, the aggregates fall apart and more smectite surfaces are exposed, resulting in an increase in the smectite dissolution rate. Thereafter, the system approaches steady state, in which the major tetrahedral and octahedral cations of smectite are released congruently.

  1. Systematic review of forsterite dissolution rate data

    NASA Astrophysics Data System (ADS)

    Rimstidt, J. Donald; Brantley, Susan L.; Olsen, Amanda A.

    2012-12-01

    This paper demonstrates a method for systematic analysis of published mineral dissolution rate data using forsterite dissolution as an example. The steps of the method are: (1) identify the data sources, (2) select the data, (3) tabulate the data, (4) analyze the data to produce a model, and (5) report the results. This method allows for a combination of critical selection of data, based on expert knowledge of theoretical expectations and experimental pitfalls, and meta-analysis of the data using statistical methods. Application of this method to all currently available forsterite dissolution rates (0 < pH < 14, and 0 < T < 150 °C) normalized to geometric surface area produced the following rate equations: For pH < 5.6 and 0° < T < 150 °C, based on 519 data logr=6.05(0.22)-0.46(0.02)pH-3683.0(63.6)1/T(R2=0.88) For pH > 5.6 and 0° < T < 150 °C, based on 125 data logr=4.07(0.38)-0.256(0.023)pH-3465(139)1/T(R2=0.92) The R2 values show that ˜10% of the variance in r is not explained by variation in 1/T and pH. Although the experimental error for rate measurements should be ± ˜30%, the observed error associated with the log r values is ˜0.5 log units (±300% relative error). The unexplained variance and the large error associated with the reported rates likely arises from the assumption that the rates are directly proportional to the mineral surface area (geometric or BET) when the rate is actually controlled by the concentration and relative reactivity of surface sites, which may be a function of duration of reaction. Related to these surface area terms are other likely sources of error that include composition and preparation of mineral starting material. Similar rate equations were produced from BET surface area normalized rates. Comparison of rate models based on geometric and BET normalized rates offers no support for choosing one normalization method over the other. However, practical considerations support the use of geometric surface area normalization

  2. An Alternative Method Of Specifying Shock Test Criteria

    NASA Technical Reports Server (NTRS)

    Ferebee, R. C.; Clayton, J.; Alldredge, D.; Irvine, T.

    2008-01-01

    Shock testing of aerospace vehicle hardware has presented many challenges over the years due to the high magnitude and short duration of the specifications. Recently, component structural failures have occurred during testing that have not manifested themselves on over 200 Space Shuttle solid rocket booster (SRB) flights (two boosters per flight). It is suspected that the method of specifying shock test criteria may be leaving important information out of the test process. The traditional test criteria specification, the shock response spectrum, can be duplicated by any number of waveforms that may not resemble the actual flight test recorded time history. One method of overcoming this limitation is described herein, which may prove useful for qualifying hardware for the upcoming Constellation Program.

  3. 16 CFR 1610.3 - Summary of test method.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... provides methods of testing the flammability of textiles from or intended to be used for apparel... surface, and held in a special apparatus at an angle of 45°. A standardized flame shall be applied to...

  4. 16 CFR 1610.3 - Summary of test method.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... provides methods of testing the flammability of textiles from or intended to be used for apparel... surface, and held in a special apparatus at an angle of 45°. A standardized flame shall be applied to...

  5. 16 CFR 1610.3 - Summary of test method.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... provides methods of testing the flammability of textiles from or intended to be used for apparel... surface, and held in a special apparatus at an angle of 45°. A standardized flame shall be applied to...

  6. 16 CFR 1610.3 - Summary of test method.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... provides methods of testing the flammability of textiles from or intended to be used for apparel... surface, and held in a special apparatus at an angle of 45°. A standardized flame shall be applied to...

  7. 40 CFR 61.137 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Emissions from Coke By-Product Recovery Plants § 61.137 Test methods and procedures. (a) Each owner or operator subject to the provisions of this subpart shall comply with the requirements in § 61.245 of 40...

  8. 40 CFR 61.137 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Emissions from Coke By-Product Recovery Plants § 61.137 Test methods and procedures. (a) Each owner or operator subject to the provisions of this subpart shall comply with the requirements in § 61.245 of 40...

  9. 40 CFR 61.137 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Emissions from Coke By-Product Recovery Plants § 61.137 Test methods and procedures. (a) Each owner or operator subject to the provisions of this subpart shall comply with the requirements in § 61.245 of 40...

  10. 40 CFR 61.137 - Test methods and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Emissions from Coke By-Product Recovery Plants § 61.137 Test methods and procedures. (a) Each owner or operator subject to the provisions of this subpart shall comply with the requirements in § 61.245 of 40...

  11. 40 CFR 61.137 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Emissions from Coke By-Product Recovery Plants § 61.137 Test methods and procedures. (a) Each owner or operator subject to the provisions of this subpart shall comply with the requirements in § 61.245 of 40...

  12. Youden test application in robustness assays during method validation.

    PubMed

    Karageorgou, Eftichia; Samanidou, Victoria

    2014-08-01

    Analytical method validation is a vital step following method development for ensuring reliable and accurate method performance. Among examined figures of merit, robustness/ruggedness study allows us to test performance characteristics of the analytical process when operating conditions are altered either deliberately or not. This study yields useful information, being a fundamental part of method validation. Since many experiments are required, this step is high demanding in time and consumables. In order to avoid the difficult task of performing too many experiments the Youden test which makes use of fractional factorial designs and has been proved to be a very effective approach. The main advantage of Youden test is the fact that it keeps the required time and effort to a minimum, since only a limited number of determinations have to be made, using combinations of the chosen investigated factors. Typical applications of this robustness test found in literature covering a wide variety of sample matrices are briefly discussed in this review.

  13. Comparison of bulk sediment and sediment elutriate toxicity testing methods

    EPA Science Inventory

    Elutriate bioassays are among numerous methods that exist for assessing the potential toxicity of sediments in aquatic systems. In this study, interlaboratory results were compared from 96-hour Ceriodaphnia dubia and Pimephales promelas static-renewal acute toxicity tests conduct...

  14. 8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW OF RADIOGRAPHY EQUIPMENT, TEST METHODS INCLUDED RADIOGRAPHY AND BETA BACKSCATTERING. (7/13/56) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  15. Sulfate scale dissolution

    SciTech Connect

    Morris, R.L.; Paul, J.M.

    1992-01-28

    This patent describes a method for removing barium sulfate scale. It comprises contacting the scale with an aqueous solution having a pH of about 8 to about 14 and consisting essentially of a chelating agent comprising a polyaminopolycarboxylic acid or salt of such an acid in a concentration of 0.1 to 1.0 M, and anions of a monocarboxylic acid selected form mercaptoacetic acid, hydroxyacetic acid, aminoacetic acid, or salicyclic acid in a concentration of 0.1 to 1.0 M and which is soluble in the solution under the selected pH conditions, to dissolve the scale.

  16. Comparison of HEPA filter test methods in corrosive environments

    SciTech Connect

    Murphy, L.P.; Fernandez, S.J.; Motes, B.G.

    1980-01-01

    The in-plant testing of process off-gas high efficiency particular air (HEPA) filters is an important quality control activity of the ALARA (As Low As Reasonably Achievable) policy at nuclear facilities. Imprecise and irreproducible data were recorded during DOP testing at the Atmospheric Protection System (APS) of the Idaho Chemical Processing Plant (ICPP). The tests at the APS are performed in an environment that has high humidity, high temperatures and has NO/sub x/ present. An evaluation of three HEPA filter test methods in corrosive environments was conducted: the dioctyl phthalate (DOP) method (US Standard Method ANSI N-101.1-1979) the sodium chloride method (British Standard 3928:1969), and the soda-fluorescein or uranine method (French Standard AFNOR STD NFX 44-011). The effects of high humidity, temperature, and oxides of nitrogen (NO/sub x/) on each method was examined. The effects of each variable and any interaction between variables on the test methods were examined. Recommendations for changes in the standard methods to reduce erratic on-line results are presented.

  17. 40 CFR 63.344 - Performance test requirements and test methods.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... testing may be used to demonstrate compliance with this subpart if: (i) The test methods and procedures... electroplating tanks and chromium anodizing tanks if the following conditions are met: (i) If a colorimetric... method (i.e., 1.0 microgram per liter of sample for AAGF and 0.5 microgram per liter of sample for...

  18. Overview of multi-input frequency domain modal testing methods with an emphasis on sine testing

    NASA Technical Reports Server (NTRS)

    Rost, Robert W.; Brown, David L.

    1988-01-01

    An overview of the current state of the art multiple-input, multiple-output modal testing technology is discussed. A very brief review of the current time domain methods is given. A detailed review of frequency and spatial domain methods is presented with an emphasis on sine testing.

  19. A study of short test and charge retention test methods for nickel-cadmium spacecraft cells

    NASA Technical Reports Server (NTRS)

    Scott, W. R.

    1975-01-01

    Methods for testing nickel-cadmium cells for internal shorts and charge retention were studied. Included were (a) open circuit voltage decay after a brief charge, (b) open circuit voltage recovery after shorting, and (c) open circuit voltage decay and capacity loss after a full charge. The investigation included consideration of the effects of prior history, of conditioning cells prior to testing, and of various test method variables on the results of the tests. Sensitivity of the tests was calibrated in terms of equivalent external resistance. The results were correlated. It was shown that a large number of variables may affect the results of these tests. It is concluded that the voltage decay after a brief charge and the voltage recovery methods are more sensitive than the charged stand method, and can detect an internal short equivalent to a resistance of about (10,000/C)ohms where "C' is the numerical value of the capacity of the cell in ampere hours.

  20. Nondestructive spot test method for magnesium and magnesium alloys

    NASA Technical Reports Server (NTRS)

    Wilson, M. L. (Inventor)

    1973-01-01

    A method for spot test identification of magnesium and various magnesium alloys commonly used in aerospace applications is described. The spot test identification involves color codes obtained when several drops of 3 M hydrochloric acid are placed on the surface to be tested. After approximately thirty seconds, two drops of this reacted acid is transferred to each of two depressions in a spot plate for additions of other chemicals with subsequent color changes indicating magnesium or its alloy.

  1. Impetus of composite mechanics on test methods for fiber composites

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.

    1978-01-01

    The impetus of composite mechanics on composite test methods and/or on interpreting test results is described by using examples from composite micromechanics, composite macromechanics and laminate theory. The specific examples included contributions such as criteria for selecting resin matrices for improved composite strength, the 10 deg off-axis tensile test, criteria for configuring hybrids and superhybrids for improved impact resistance and the reduced bending rigidities concept for buckling and vibration analyses.

  2. Propagation and Dissolution of CO2 bubbles in Algae Photo-bioreactors

    NASA Astrophysics Data System (ADS)

    Kosaraju, Srinivas

    2015-11-01

    Research grade photo-bioreactors are used to study and cultivate different algal species for biofuel production. In an attempt to study the growth properties of a local algal species in rain water, a custom made bioreactor is designed and being tested. Bio-algae consumes dissolved CO2 in water and during its growth cycle, the consumed CO2 must be replenished. Conventional methods use supply of air or CO2 bubbles in the growth medium. The propagation and dissolution of the bubbles, however, are strongly dependent on the design parameters of the photo-bioreactor. In this paper, we discuss the numerical modeling of the air and CO2 bubble propagation and dissolution in the photo-bioreactor. Using the results the bioreactor design will be modified for maximum productivity.

  3. Primer Stepper Motor Nomenclature, Definition, Performance and Recommended Test Methods

    NASA Technical Reports Server (NTRS)

    Starin, Scott; Shea, Cutter

    2014-01-01

    There has been an unfortunate lack of standardization of the terms and components of stepper motor performance, requirements definition, application of torque margin and implementation of test methods. This paper will address these inconsistencies and discuss in detail the implications of performance parameters, affects of load inertia, control electronics, operational resonances and recommended test methods. Additionally, this paper will recommend parameters for defining and specifying stepper motor actuators. A useful description of terms as well as consolidated equations and recommended requirements is included.

  4. 40 CFR 60.547 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Manufacturing Industry § 60.547 Test methods and procedures. (a) The test methods in appendix A to this part... of the duct or at a point no closer to the walls than 1.0 meter (3.3 feet). The minimum sample volume shall be 0.003 dry standard cubic meter (dscm) (0.11 dry standard cubic feet (dscf)) except that...

  5. A Conditional Exposure Control Method for Multidimensional Adaptive Testing

    ERIC Educational Resources Information Center

    Finkelman, Matthew; Nering, Michael L.; Roussos, Louis A.

    2009-01-01

    In computerized adaptive testing (CAT), ensuring the security of test items is a crucial practical consideration. A common approach to reducing item theft is to define maximum item exposure rates, i.e., to limit the proportion of examinees to whom a given item can be administered. Numerous methods for controlling exposure rates have been proposed…

  6. 40 CFR 61.304 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... performance test according to Method 22 of appendix A of 40 CFR part 60 shall be performed to determine... conducted during at least three complete loading cycles with a separate test run for each loading cycle. The observation period for detecting visible emissions shall encompass each loading cycle. Integrated sampling...

  7. 40 CFR 61.304 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... performance test according to Method 22 of appendix A of 40 CFR part 60 shall be performed to determine... conducted during at least three complete loading cycles with a separate test run for each loading cycle. The observation period for detecting visible emissions shall encompass each loading cycle. Integrated sampling...

  8. 40 CFR 60.685 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... § 60.8(b). (b) The owner or operator shall conduct performance tests while the product with the highest... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standard of Performance for Wool Fiberglass Insulation Manufacturing Plants § 60.685 Test methods and procedures. (a) In conducting the performance...

  9. 40 CFR 60.374 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Battery Manufacturing Plants § 60.374 Test methods and procedures. (a) In conducting the performance tests..., if applicable, the volumetric flow rate (Qsda) of the effluent gas. The sampling time and sample...”, mg/dscm (gr/dscf). Qsda=volumetric flow rate of effluent gas from facility “a”, dscm/hr (dscf/hr)....

  10. 40 CFR 60.374 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Battery Manufacturing Plants § 60.374 Test methods and procedures. (a) In conducting the performance tests..., if applicable, the volumetric flow rate (Qsda) of the effluent gas. The sampling time and sample...”, mg/dscm (gr/dscf). Qsda=volumetric flow rate of effluent gas from facility “a”, dscm/hr (dscf/hr)....

  11. 40 CFR 60.374 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Battery Manufacturing Plants § 60.374 Test methods and procedures. (a) In conducting the performance tests... concentration (CPb) and, if applicable, the volumetric flow rate (Qsda) of the effluent gas. The sampling time... from facility “a”, mg/dscm (gr/dscf). Qsda = volumetric flow rate of effluent gas from facility...

  12. 40 CFR 60.374 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Battery Manufacturing Plants § 60.374 Test methods and procedures. (a) In conducting the performance tests..., if applicable, the volumetric flow rate (Qsda) of the effluent gas. The sampling time and sample...”, mg/dscm (gr/dscf). Qsda=volumetric flow rate of effluent gas from facility “a”, dscm/hr (dscf/hr)....

  13. 40 CFR 60.74 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Nitric Acid Plants § 60.74 Test methods and procedures. (a) In conducting the performance tests required in § 60.8...=emission rate of NOX as NO2, kg/metric ton (lb/ton) of 100 percent nitric acid. Cs=concentration of NOX...

  14. Dissolution of quartz in aqueous basic solution, 106-236 C - Surface kinetics of 'perfect' crystallographic faces

    NASA Technical Reports Server (NTRS)

    Gratz, Andrew J.; Bird, Peter; Quiro, Glenn B.

    1990-01-01

    A highly accurate method, called the negative crystal method, for determining the rate of dissolution on specific crystallographic faces of crystals was developed, in which the dissolution rates of nominally perfect crystal faces are obtained by measuring the size of individual negative crystals during a sequence of dissolution steps. The method was applied to determine the apparent activation energy and rate constants for the dissolution of quartz in 0.01 M KOH solutions at temperatures from 106 to 236 C. Also investigated were the effects of hydroxyl activity and ionic strength. The apparent activation energies for the dissolution of the prism and of the rhomb were determined.

  15. Tissue dissolution and modifications in dentin composition by different sodium hypochlorite concentrations

    PubMed Central

    TARTARI, Talita; BACHMANN, Luciano; MALIZA, Amanda Garcia Alves; ANDRADE, Flaviana Bombarda; DUARTE, Marco Antonio Hungaro; BRAMANTE, Clovis Monteiro

    2016-01-01

    ABSTRACT Sodium hypochlorite (NaOCl) remains the most used irrigation solution during root canal preparation because of characteristics such as wide-spectrum antimicrobial activity and organic tissue dissolution capacity. However, these solutions can alter dentin composition and there is no consensus on the optimal concentration of NaOCl to be used. Objectives To determine the organic matter dissolution and changes in dentin chemical composition promoted by different concentrations of NaOCl over time. Material and Methods: Fragments of bovine muscle tissue were weighed before and after 5, 10, and 15 min of immersion in the groups (n=10): G1- 0.9% saline solution; G2- 1% NaOCl; G3- 2.5% NaOCl; and G4- 5% NaOCl. Bovine dentin fragments were subjected to the same irrigants and absorption spectra were collected by Attenuated Total Reflectance of Fourier Transform Infrared Spectroscopy (ATR-FTIR) before and after 0,5, 1, 2, 3, 5, 8, and 10 min of immersion in the solutions. The ratios of the amide III/phosphate and carbonate/phosphate absorption bands were determined. The tissue dissolution and carbonate/phosphate ratios were submitted to the two-way analysis of variance (ANOVA) with Tukey’s multiple-comparison test (α<0.05) and to the one-way analysis of variance with Tukey’s (α<0.05). The amide III/phosphate ratio was analyzed by Friedman test (α<0.05) and the Kruskal-Wallis test with Dunn’s post-hoc (α<0.05). Results The increase in NaOCl concentration and contact time intensified the dissolution of organic matter and dentin collagen with reduction in the amide III/phosphate ratio. Significant differences between all groups (p<0.05) were observed in the dissolution of organic matter at 10 min and in the amide III/phosphate ratio between the saline solution and 5% NaOCl at 5 min. The carbonate/phosphate ratio decreased significantly in G2, G3, and G4 after 0,5 min of immersion (p<0.05), but more alterations did not occur in the subsequent periods (p>0

  16. Multiphase Dissolution Model

    1999-06-08

    This program simulates the leaching behavior of glass-ceramic monoliths or particles immersed in liquids. The monoliths or particles may be composed of up to 10 separate compounds, each with different densities and forward leach rate constants. Each compound in turn can be composed of up to 10 species (elements, oxides, etc.). A data file is used to store the physical information about the compounds, i.e., density, forward rate constant and the percentages of each speciesmore » making up each compound. Once the program has input the data file and the user has setup the experimental parameters, the program begins a calculation loop for each time interval, :{Delta}t [days]. The time interval is calculated by dividing the duration of the experiment by the number of data points desired by the user. The program can simulate static conditions as would be the case for a standard leach test or under flowing water conditions which might be found in nature. It can also account for precipitation out of solution for various compounds, if the precipitation coefficients are known. An output data file is created showing the amount of each species in solution as a function of time. An accompanying program, LDATA, is used to create and manage data files for input into the MDM program. The files contain physical data about the compounds, and species making up the material.« less

  17. High Level Waste System Impacts from Acid Dissolution of Sludge

    SciTech Connect

    KETUSKY, EDWARD

    2006-04-20

    This research evaluates the ability of OLI{copyright} equilibrium based software to forecast Savannah River Site High Level Waste system impacts from oxalic acid dissolution of Tank 1-15 sludge heels. Without further laboratory and field testing, only the use of oxalic acid can be considered plausible to support sludge heel dissolution on multiple tanks. Using OLI{copyright} and available test results, a dissolution model is constructed and validated. Material and energy balances, coupled with the model, identify potential safety concerns. Overpressurization and overheating are shown to be unlikely. Corrosion induced hydrogen could, however, overwhelm the tank ventilation. While pH adjustment can restore the minimal hydrogen generation, resultant precipitates will notably increase the sludge volume. OLI{copyright} is used to develop a flowsheet such that additional sludge vitrification canisters and other negative system impacts are minimized. Sensitivity analyses are used to assess the processability impacts from variations in the sludge/quantities of acids.

  18. 40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... that the subpart in 40 CFR part 63 requires. If you want to expand the applicable range of the method... operator of an affected source subject to requirements under 40 CFR part 63 can use to validate an alternative test method to a test method required in 40 CFR part 63 or to validate a stand-alone...

  19. 40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... that the subpart in 40 CFR part 63 requires. If you want to expand the applicable range of the method... operator of an affected source subject to requirements under 40 CFR part 63 can use to validate an alternative test method to a test method required in 40 CFR part 63 or to validate a stand-alone...

  20. 40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... that the subpart in 40 CFR part 63 requires. If you want to expand the applicable range of the method... operator of an affected source subject to requirements under 40 CFR part 63 can use to validate an alternative test method to a test method required in 40 CFR part 63 or to validate a stand-alone...

  1. 40 CFR Appendix A to Part 63 - Test Methods Pollutant Measurement Methods From Various Waste Media

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... that the subpart in 40 CFR part 63 requires. If you want to expand the applicable range of the method... operator of an affected source subject to requirements under 40 CFR part 63 can use to validate an alternative test method to a test method required in 40 CFR part 63 or to validate a stand-alone...

  2. Method for Smoke Spread Testing of Large Premises

    NASA Astrophysics Data System (ADS)

    Walmerdahl, P.; Werling, P.

    2001-11-01

    A method for performing non-destructive smoke spread tests has been developed, tested and applied to several existing buildings. Burning methanol in different size steel trays cooled by water generates the heat source. Several tray sizes are available to cover fire sources up to nearly 1MW. The smoke is supplied by means of a suitable number of smoke generators that produce a smoke, which can be described as a non-toxic aerosol. The advantage of the method is that it provides a means for performing non-destructive tests in already existing buildings and other installations for the purpose of evaluating the functionality and design of the active fire protection measures such as smoke extraction systems, etc. In the report, the method is described in detail and experimental data from the try-out of the method are also presented in addition to a discussion on applicability and flexibility of the method.

  3. An evaluation of the whole effluent toxicity test method

    SciTech Connect

    Osteen, D.V.

    1999-12-17

    Whole effluent toxicity (WET) testing has become increasingly more important to the Environmental Protection Agency (EPA) and the States in the permitting of wastewater discharges from industry and municipalities. The primary purpose of the WET test is to protect aquatic life by predicting the effect of an effluent on the receiving stream. However, there are both scientific and regulatory concerns that using WET tests to regulate industrial effluents may result in either false positives and/or false negatives. In order to realistically predict the effect of an effluent on the receiving stream, the test should be as representative as possible of the conditions in the receiving stream. Studies (Rand and Petrocelli 1985) suggested several criteria for an ideal aquatic toxicity test organism, one of which is that the organism be indigenous to, or representative of, the ecosystem receiving the effluent. The other component needed in the development of a predictive test is the use of the receiving stream water or similar synthetic water as the control and dilution water in the test method. Use of an indigenous species and receiving water in the test should help reduce the variability in the method and allow the test to predict the effect of the effluent on the receiving stream. The experience with toxicity testing at the Savannah River Site (SRS) has yielded inconclusive data because of the inconsistency and unreliability of the results. The SRS contention is that the WET method in its present form does not adequately mimic actual biological/chemical conditions of the receiving streams and is neither reasonable nor accurate. This paper discusses the rationale for such a position by SRS on toxicity testing in terms of historical permitting requirements, outfall effluent test results, standard test method evaluation, scientific review of alternate test species, and concerns over the test method expressed by other organizations. This paper presents the Savannah River Site

  4. The Evaluation of Flammability Properties Regarding Testing Methods

    NASA Astrophysics Data System (ADS)

    Osvaldová, Linda Makovická; Gašpercová, Stanislava

    2015-12-01

    In this paper, we address the historical comparison methods with current methods for the assessment of flammability characteristics for materials an especially for wood, wood components and wooden buildings. Nowadays in European Union brings harmonization in evaluated of standards into each European country and try to make one concept of evaluated the flammability properties. In each European country to the one standard level which will be used by evaluation of materials regarding flammability. In our article we focused mainly on improving the evaluation methods in terms of flammability characteristics of using materials at building industry. In the article we present examples of different assessment methods at their own test methods in terms of fire prevention. On the base of old compared of materials by STN, BS and DIN methods for testing materials on fire and new methods of evaluating the flammability properties regarding EU standards before and after starting the flash over.

  5. Electrochemical polishing of thread fastener test specimens of nickel-chromium iron alloys

    DOEpatents

    Kephart, Alan R.

    1991-01-01

    An electrochemical polishing device and method for selective anodic dissolution of the surface of test specimens comprised, for example, of nickel-chromium-iron alloys, which provides for uniform dissolution at the localized sites to remove metal through the use of a coiled wire electrode (cathode) placed in the immediate proximity of the working, surface resulting in a polished and uniform grain boundary.

  6. Testing methods and techniques: Testing electrical and electronic devices: A compilation

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The methods, techniques, and devices used in testing various electrical and electronic apparatus are presented. The items described range from semiconductor package leak detectors to automatic circuit analyzer and antenna simulators for system checkout. In many cases the approaches can result in considerable cost savings and improved quality control. The testing of various electronic components, assemblies, and systems; the testing of various electrical devices; and the testing of cables and connectors are explained.

  7. WASHING AND DEMONSTRATION OF THE DWPF FLOWSHEET IN THE SRNL SHIELDED CELLS USING POST ALUMINUM DISSOLUTION TANK 51 SLUDGE SLURRY

    SciTech Connect

    Pareizs, J; Cj Bannochie, C; Damon Click, D; Erich Hansen, E; Dan Lambert, D; Michael Stone, M

    2008-04-28

    The remaining contents of Tank 51 from Sludge Batch 4 will be blended with Purex sludge from Tank 7 to constitute Sludge Batch 5 (SB5). The Savannah River Site (SRS) Liquid Waste Organization (LWO) has completed caustic addition to Tank 51 to perform low temperature Al dissolution on the H-Modified (HM) sludge material to reduce the total mass of sludge solids and Al being fed to the Defense Waste Processing Facility (DWPF). The Savannah River National Lab (SRNL) has also completed aluminum dissolution tests using a 3-L sample of Tank 51 sludge slurry through funding by DOE EM-21. This report documents assessment of downstream impacts of the aluminum dissolved sludge, which were investigated so technical issues could be identified before the start of SB5 processing. This assessment included washing the aluminum dissolved sludge to a Tank Farm projected sodium concentration and weight percent insoluble solids content and DWPF Chemical Process Cell (CPC) processing using the washed sludge. Based on the limited testing, the impact of aluminum dissolution on sludge settling is not clear. Settling was not predictable for the 3-L sample. Compared to the post aluminum dissolution sample, settling after the first wash was slower, but settling after the second wash was faster. For example, post aluminum dissolution sludge took six days to settle to 60% of the original sludge slurry height, while Wash 1 took nearly eight days, and Wash 2 only took two days. Aluminum dissolution did impact sludge rheology. A comparison between the as-received, post aluminum dissolution and washed samples indicate that the downstream materials were more viscous and the concentration of insoluble solids less than that of the starting material. This increase in viscosity may impact Tank 51 transfers to Tank 40. The impact of aluminum dissolution on DWPF CPC processing cannot be determined because acid addition for the Sludge Receipt and Adjustment Tank (SRAT) cycle was under-calculated and thus

  8. Method and apparatus for tensile testing of metal foil

    NASA Technical Reports Server (NTRS)

    Wade, O. W. (Inventor)

    1976-01-01

    A method for obtaining accurate and reproducible results in the tensile testing of metal foils in tensile testing machines is described. Before the test specimen are placed in the machine, foil side edges are worked until they are parallel and flaw free. The specimen are also aligned between and secured to grip end members. An aligning apparatus employed in the method is comprised of an alignment box with a longitudinal bottom wall and two upright side walls, first and second removable grip end members at each end of the box, and a means for securing the grip end members within the box.

  9. The Rocketdyne Multifunction Tester. Part 1: Test Method

    NASA Technical Reports Server (NTRS)

    Murphy, Brian T.; Scharrer, Joseph K.; Sutton, Robert F.

    1991-01-01

    The Rocketdyne Multifunction Tester is a general purpose test apparatus which utilizes axial and radial magnetic bearings as shaft excitation devices. The tester is modular in design so that different seal and bearing packages can be tested on the same test stand. The tester will be used for rotordynamic coefficient extraction, as well as life and fluid/material compatibility evaluations. Use of a magnetic bearing as a shaft excitation device opens up many possibilities for shaft excitation and rotordynamic coefficient extraction. In addition to describing the basic apparatus, some of the excitation and extraction methods are described. Some of the excitation methods to be discussed include random, aperiodic, harmonic, impulse and chirp.

  10. How good is cola for dissolution of gastric phytobezoars?

    PubMed Central

    Lee, Beom Jae; Park, Jong-Jae; Chun, Hoon Jai; Kim, Ji Hoon; Yeon, Jong Eun; Jeen, Yoon Tae; Kim, Jae Seon; Byun, Kwan Soo; Lee, Sang Woo; Choi, Jae Hyun; Kim, Chang Duck; Ryu, Ho Sang; Bak, Young-Tae

    2009-01-01

    AIM: To evaluate the efficacy of cola treatment for gastric phytobezoars, including diospyrobezoars. METHODS: A total of 17 patients (range: 48 to 78 years) with symptomatic gastric phytobezoars treated with cola and adjuvant endoscopic therapy were reviewed. Three liters of cola lavage (10 cases) or drink (7 cases) were initially used, and then endoscopic fragmentation was done for the remnant bezoars by using a lithotripsy basket or a polypectomy snare. The overall success of dissolving a gastric phytobezoars with using three liters of cola and the clinical and endoscopic findings were compared retrospectively between four cases of complete dissolution by using only cola and 13 cases of partial dissolution with cola. RESULTS: After 3 L of cola lavage or drinking, a complete dissolution of bezoars was achieved in four patients (23.5%), while 13 cases (76.5%) were only partially dissolved. Phytobezoars (4 of 6 cases) were observed more frequently than diospyrobezoars (0 of 11) in the group that underwent complete dissolution (P = 0.006). Gender, symptom duration, size of bezoar and method of cola administration were not significantly different between the two groups. Twelve of 13 patients with residual bezoars were completely treated with a combination of cola and endoscopic fragmentation. CONCLUSION: The rate of complete dissolution with three liters of cola was 23.5%, but no case of diospyrobezoar was completely dissolved using this method. However, pretreatment with cola may be helpful and facilitate endoscopic fragmentation of gastric phytobezoars. PMID:19437568

  11. Testing and Validation of the Dynamic Inertia Measurement Method

    NASA Technical Reports Server (NTRS)

    Chin, Alexander W.; Herrera, Claudia Y.; Spivey, Natalie D.; Fladung, William A.; Cloutier, David

    2015-01-01

    The Dynamic Inertia Measurement (DIM) method uses a ground vibration test setup to determine the mass properties of an object using information from frequency response functions. Most conventional mass properties testing involves using spin tables or pendulum-based swing tests, which for large aerospace vehicles becomes increasingly difficult and time-consuming, and therefore expensive, to perform. The DIM method has been validated on small test articles but has not been successfully proven on large aerospace vehicles. In response, the National Aeronautics and Space Administration Armstrong Flight Research Center (Edwards, California) conducted mass properties testing on an "iron bird" test article that is comparable in mass and scale to a fighter-type aircraft. The simple two-I-beam design of the "iron bird" was selected to ensure accurate analytical mass properties. Traditional swing testing was also performed to compare the level of effort, amount of resources, and quality of data with the DIM method. The DIM test showed favorable results for the center of gravity and moments of inertia; however, the products of inertia showed disagreement with analytical predictions.

  12. 40 CFR 265.1034 - Test methods and procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Process Vents § 265.1034 Test methods and procedures. (a... following requirements: (1) Monitoring shall comply with Reference Method 21 in 40 CFR part 60. (2)...

  13. 40 CFR 265.1034 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Process Vents § 265.1034 Test methods and procedures. (a... following requirements: (1) Monitoring shall comply with Reference Method 21 in 40 CFR part 60. (2)...

  14. 40 CFR 264.1063 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Equipment Leaks § 264.1063 Test methods and procedures. (a) Each owner or... CFR part 60. (2) The detection instrument shall meet the performance criteria of Reference Method...

  15. 40 CFR 264.1034 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Process Vents § 264.1034 Test methods and procedures. (a) Each owner or... requirements: (1) Monitoring shall comply with Reference Method 21 in 40 CFR part 60. (2) The...

  16. 40 CFR 264.1034 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Process Vents § 264.1034 Test methods and procedures. (a) Each owner or... requirements: (1) Monitoring shall comply with Reference Method 21 in 40 CFR part 60. (2) The...

  17. 40 CFR 264.1063 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Equipment Leaks § 264.1063 Test methods and procedures. (a) Each owner or... CFR part 60. (2) The detection instrument shall meet the performance criteria of Reference Method...

  18. 40 CFR 265.1063 - Test methods and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Equipment Leaks § 265.1063 Test methods and procedures. (a... Method 21 in 40 CFR part 60. (2) The detection instrument shall meet the performance criteria...

  19. 40 CFR 265.1063 - Test methods and procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Equipment Leaks § 265.1063 Test methods and procedures. (a... Method 21 in 40 CFR part 60. (2) The detection instrument shall meet the performance criteria...

  20. 40 CFR 265.1063 - Test methods and procedures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) INTERIM STATUS STANDARDS FOR OWNERS AND OPERATORS OF HAZARDOUS WASTE TREATMENT, STORAGE, AND DISPOSAL FACILITIES Air Emission Standards for Equipment Leaks § 265.1063 Test methods and procedures. (a... Method 21 in 40 CFR part 60. (2) The detection instrument shall meet the performance criteria...