Science.gov

Sample records for accidental drop scenarios

  1. IMPACT ANALYSIS OF SPENT FUEL DRY CASKS UNDER ACCIDENTAL DROP SCENARIOS.

    SciTech Connect

    BRAVERMAN,J.I.; MORANTE,R.J.; XU,J.; HOFMAYER,C.H.; SHAUKAT,S.K.

    2003-08-17

    A series of analyses were performed to assess the structural response of spent nuclear fuel dry casks subjected to various handling and on-site transfer events. The results of these analyses are being used by the Nuclear Regulatory Commission (NRC) to perform a probabilistic risk assessment (PRA). Although the PRA study is being performed for a specific nuclear plant, the PRA study is also intended to provide a framework for a general methodology that could also be applied to other dry cask systems at other nuclear plants. The dry cask system consists of a transfer cask, used for handling and moving the multi-purpose canister OLIIpC that contains the fuel, and a storage cask, used to store the MPC and fuel on a concrete pad at the site. This paper describes the analyses of the casks for two loading events. The first loading consists of dropping the transfer cask while it is lowered by a crane to a concrete floor at ground elevation. The second loading consists of dropping the storage cask while it is being transferred to the concrete storage pad outdoors. Three dimensional finite element models of the transfer cask and storage cask, containing the MPC and fuel, were utilized to perform the drop analyses. These models were combined with finite element models of the target structures being impacted. The transfer cask drop analyses considered various drop heights for the cask impacting the reinforced concrete floor at ground level. The finite element model of the target included a section of the concrete floor and concrete wall supporting the floor. The storage cask drop analyses evaluated a 30.5 cm (12 in.) drop of the cask impacting three different surfaces: reinforced concrete, asphalt, and gravel.

  2. IMPACT ANALYSIS OF SPENT FUEL DRY CASKS UNDER ACCIDENTAL DROP SCENARIOS.

    SciTech Connect

    BRAVERMAN,J.I.; MORANTE,R.J.; XU,J.; HOFMAYER,C.H.; SHAUKAT,S.K.

    2003-03-17

    A series of analyses were performed to assess the structural response of spent nuclear fuel dry casks subjected to various handling and on-site transfer events. The results of these analyses are being used by the Nuclear Regulatory Commission (NRC) to perform a probabilistic risk assessment (PRA). Although the PRA study is being performed for a specific nuclear plant, the PRA study is also intended to provide a framework for a general methodology that could also be applied to other dry cask systems at other nuclear plants. The dry cask system consists of a transfer cask, used for handling and moving the multi-purpose canister (MPC) that contains the fuel, and a storage cask, used to store the MPC and fuel on a concrete pad at the site. This paper describes the analyses of the casks for two loading events. The first loading consists of dropping the transfer cask while it is lowered by a crane to a concrete floor at ground elevation. The second loading consists of dropping the storage cask while it is being transferred to the concrete storage pad outdoors. Three dimensional finite element models of the transfer cask and storage cask, containing the MPC and fuel, were utilized to perform the drop analyses. These models were combined with finite element models of the target structures being impacted. The transfer cask drop analyses considered various drop heights for the cask impacting the reinforced concrete floor at ground level. The finite element model of the target included a section of the concrete floor and concrete wall supporting the floor. The storage cask drop analyses evaluated a 30.5 cm (12 in.) drop of the cask impacting three different surfaces: reinforced concrete, asphalt, and gravel.

  3. Numerical and Experimental Investigations of Polyurethane Foam for Use as Cask Impact Limiter in Accidental Drop Scenarios - 12099

    SciTech Connect

    Kasparek, Eva M.; Voelzke, Holger; Scheidemann, Robert; Zencker, Uwe

    2012-07-01

    Rigid, closed-cell polyurethane foams are frequently used as cask impact limiters in nuclear materials and hazardous waste transport due to their high energy-absorption potential. When assessing the cask integrity in accidental scenarios based on numerical simulations, a description of the foam damping properties is required for different strain rates and for a wide temperature range with respect to waste heat generation in conjunction with critical operating and environmental conditions. Implementation and adaption of a respective finite element material model strongly relies on an appropriate experimental data base. Even though extensive impact experiments were conducted e.g. in Sandia National Laboratories, Savannah River National Laboratory and by Rolls Royce plc, not all relevant factors were taken into account. Hence, BAM who is in charge of the mechanical evaluation of such packages within the approval procedure in Germany, incorporated systematic test series into a comprehensive research project aimed to develop numerical methods for a couple of damping materials. In a first step, displacement driven compression tests have been performed on confined, cubic specimens at five loading rates ranging from 0.02 mm/s to 3 m/s at temperatures between +90 deg. C and -40 deg. C. Materials include two different polyurethane foam types called FR3718 and FR3730 having densities of 280 kg/m{sup 3} and 488 kg/m{sup 3} from the product line-up of General Plastics Manufacturing Company. Their data was used to adapt an advanced plasticity model allowing for reliably simulating cellular materials under multi-axial compression states. Therefore, an automated parameter identification procedure had been established by combining an artificial neural network with local optimization techniques. Currently, the selected numerical material input values are validated and optimized by means of more complex loading configurations with the prospect of establishing methods applicable to impact limiters under severe accidental conditions. The reference data base is provided by experiments, where weights between 212 kg and 1200 kg have been dropped from heights between 1.25 m and 7 m on confined 10 cm cubic foam specimens. By presenting the deviations between experimental values and the corresponding output of finite element simulations, the potentials and restrictions of the resulting models are highlighted. Systematic compression tests on polyurethane foams had been performed at BAM test site within the framework of a research project on impact limiters for handling casks for radioactive waste. The experimental results had been used to adapt numerical models for simulating the behaviour of different foam types at different temperatures. The loading speed, however, turned out to have a major influence on their flow curves that can not be captured by simple strain-rate dependent multipliers. Especially for guided drop tests that come close to real accidental scenarios there is a significant gap between experimental and numerical results even when applying such advanced material models. Hence, the extensive data base is currently deployed for expanding the standard algorithms to include adequate dynamic hardening factors. (authors)

  4. An experimental study on the uptake factor of tungsten oxide particles resulting from an accidentally dropped storage container.

    PubMed

    Gao, Zhi; Zhang, J S; Byington, Jerry G A

    2013-01-01

    A test procedure was developed and verified to measure the airborne concentrations of particles of different sizes (0.5-20 μm) within the vicinity of a dropped container when a significant portion of the tungsten oxide powder (simulating uranium oxide) is ejected from the container. Tests were carried out in a full-scale stainless steel environmental chamber with an interior volume of 24.1 m(3). Thirty-two drop tests were performed, covering variations in dropping height, room air movement, landing scenario, and lid condition. Assuming a breathing rate of 1.2 m(3)/hr, the uptake factor during the first 10 min was calculated to be between 1.13 × 10(-9) and 1.03 × 10(-7) in reference to the amount loaded; or between 6.44 × 10(-8) and 3.55 × 10(-4) in reference to the amount spilled. Results provide previously unavailable data for estimating the exposure and associated risk to building occupants in the case of an accidental dropping of heavy powder containers. The test data show that for spills larger than 0.004 g, the power-law correlation between the spill uptake factor and the spilled mass (i.e., SUF = 2.5 × 10(-5) × Spill_Mass(-0.667)) established from the test data is smaller and a more accurate estimate than the constant value of 10(-3) assumed in the Department of Energy Nuclear Material Packaging Manual. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplementary resource: an online supplementary table of all cumulative uptake amounts at 10 min for all test data.]. PMID:23679340

  5. Failure Criteria for Evaluating Accidental Drops of Fuel Containers at INTEC

    SciTech Connect

    Miller, G. K.

    1998-10-01

    This report presents a failure criterion that has been developed for use in evaluating fuel containers at the Idaho Nuclear Technology and Engineering Center (INTEC) for accidental drop events. The criterion would typically be used in dynamic finite element analyses using the ABA-QUS/Explicit program. The failure criterion used in the past is generally considered to substantially underestimate the strength and ductility of the materials involved. The new criterion is intended to be more realistic, allowing for more accurate impact analyses. The criterion is based on the distortion energy theory, which is considered to be appropriate for the ductile materials typically used in fuel containers. Also addressed in development of the criterion were the effects of strain rate and hydrostatic stress. The importance of these factors, however, is highly dependent on the material used. Three materials specifically addressed in this study were stainless steel, aluminum, and lead. The criterion is presented in the form of guidelines and recommendations that are based on material data obtained from the literature. The most significant difference between these and the previous criterion is that ductile materials are allowed to strain to much higher levels before they are considered to fail.

  6. Accidental Drop of a Carbon Steel/Lead Shipping Cask (HFEF 14) at Low Temperatures

    SciTech Connect

    Brian D. Hawkes; Michael E. Nitzel

    2007-08-01

    A shielded cask is used to transport radioactive materials between facilities at the Idaho National Laboratory. The cask was fabricated with an outer and inner shell of A36 carbon steel with lead poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to low-temperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask at subzero temperatures. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 1.83m (6 ft.) Finite element models of the cask and its contents were solved and post processed using the ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and door structure. The cask payload outer waste can remains in the cask but will experience some permanent plastic deformation in each drop. It will not be deformed to the point where it will rupture, thus maintaining confinement of the can contents.

  7. ACCIDENTAL DROP OF A CARBON STEEL/LEAD SHIPPING CASK AT LOW TEMPERATURES

    SciTech Connect

    B. D. Hawkes; K. R. Durstine

    2007-07-01

    A shielded cask is used to transport radioactive materials between facilities. The cask was fabricated with an outer and inner shell of hot rolled low carbon steel. Lead was poured in the annular space between the shells to provide radiation shielding. Carbon steel is known to be susceptible to lowtemperature brittle fracture under impact loading. This paper will present the analysis results representing postulated transportation accidents during on-site transfers of the cask. The accident scenarios were based on a series of cask drops onto a rigid surface from a height of 6 ft assuming brittle failure of the cask shell at subzero temperatures. Finite element models of the cask and its contents were solved and post processed using ABAQUS software. Each model was examined for failure to contain radioactive materials and/or significant loss of radiation shielding. Results of these analyses show that the body of the cask exhibits considerable ruggedness and will remain largely intact after the impact. There will be deformation of the main cask body with localized brittle failure of the cask outer shell and components and but no complete penetration of the cask shielding. The cask payload outer waste can will experience some permanent plastic deformation in each drop, but will not be deformed to the point where it will rupture, thus maintaining confinement of the can contents.

  8. NAPL migration and ecotoxicity of conventional and renewable fuels in accidental spill scenarios.

    PubMed

    Malk, Vuokko; Barreto Tejera, Eduardo; Simpanen, Suvi; Dahl, Mari; Mäkelä, Riikka; Häkkinen, Jani; Kiiski, Anna; Penttinen, Olli-Pekka

    2014-01-01

    Fuels derived from non-petroleum renewable resources have raised interest due to their potential in replacing petroleum-based fuels, but information on their fate and effects in the terrestrial and aquatic environments in accidental spill scenario is limited. In this study, migration of four fuels (conventional diesel, conventional gasoline, renewable diesel NExBTL, and ethanol-blended gasoline RE85 containing maximum 85% ethanol) as non-aqueous phase liquids (NAPL) in soil was demonstrated in a laboratory-scale experiment. Ecotoxicity data was produced for the same fuels. There was no significant difference in migration of conventional and renewable diesel, but gasoline migrated 1.5 times deeper and 7-9 times faster in sand than diesel. RE85 spread horizontally wider but not as deep (p < 0.05) as conventional gasoline. Conventional gasoline was the most toxic (lethal concentration [LC50] 20 mg/kg total hydrocarbon content [THC]) among the studied fuels in soil toxicity test with earthworm Eisenia fetida followed by ethanol-blended gasoline (LC50 1,643 mg/kg THC) and conventional diesel (LC50 2,432 mg/kg THC), although gasoline evaporated fast from soil. For comparison, the toxicity of the water-accommodated fractions (WAF) of the fuels was tested with water flea Daphnia magna and Vibrio fischeri, also demonstrating groundwater toxicity. The WAF of conventional gasoline and RE85 showed almost similar toxicity to both the aquatic test species. EC50 values of 1:10 (by volume) WAF were 9.9 %WAF (gasoline) and 9.3 %WAF (RE85) to D. magna and 9.3 %WAF (gasoline) and 12.3 %WAF (RE85) to V. fischeri. Low solubility decreased toxicity potential of conventional diesel in aquatic environment, but direct physical effects of oil phase pose a threat to organisms in nature. Renewable diesel NExBTL did not show clear toxicity to any test species. PMID:24764004

  9. A simulation study of dispersion of air borne radionuclides from a nuclear power plant under a hypothetical accidental scenario at a tropical coastal site

    NASA Astrophysics Data System (ADS)

    Srinivas, C. V.; Venkatesan, R.

    Meteorological condition in coastal regions is diurnally variable and spatially heterogeneous due to complex topography, land-sea interface, etc. A wide range of dispersion conditions is possible on a given day in the coastal regions. In case of inadvertent accidental situations, though unlikely, it would be necessary to examine the potentially severe case among different dynamically occurring local atmospheric conditions for dispersion and its range of impact around a nuclear power plant for safety analysis. In this context, dispersion of air borne radioactive effluents during a hypothetical accidental scenario from a proposed prototype fast breeder reactor (PFBR) at an Indian coastal site, Kalpakkam, is simulated using a 3-D meso-scale atmospheric model MM5 and a random walk particle dispersion model FLEXPART. A simulation carried out for a typical summer day predicted the development of land-sea breeze circulation and thermal internal boundary layer (TIBL) formation, which have been confirmed by meteorological observations. Analysis of dose distribution shows that the maximum dose for releases from a 100 m stack occurs at two places within 4 km distance during sea breeze/TIBL fumigation hours. Maximum dose also occurred during nighttime stable conditions. Results indicate that, on the day of present study, the highest concentrations occurred during periods of TIBL fumigation rather than during stable atmospheric conditions. Further, the area of impact (plume width at the surface) spreads up to a down wind distance of 4 km during fumigation condition. Simulation over a range of 25 km has shown turning of plume at the incidence of sea breeze circulation and two different dispersion patterns across the sea breeze front. These results are significant in comparison to the expected pattern shown by Gaussian plume model used for routine analysis.

  10. A combined coalescence gene-dropping tool for evaluating genomic selection in complex scenarios (ms2gs).

    PubMed

    Pérez-Enciso, M; Legarra, A

    2016-04-01

    We present ms2gs, a combined coalescence - gene dropping (i.e. backward-forward) simulator for complex traits. It therefore aims at combining the advantages of both approaches. It is primarily conceived for very short term, recent scenarios such as those that are of interest in animal and plant breeding. It is very flexible in terms of defining QTL architecture and SNP ascertainment bias, and it allows for easy modelling of alternative markers such as RADs. It can use real sequence or chip data or generate molecular polymorphisms via the coalescence. It can generate QTL conditional on extant molecular information, such as low-density genotyping. It models (simplistically) sequence, imputation or genotyping errors. It requires as input both genotypic data in plink or ms formats, and a pedigree that is used to perform the gene dropping. By default, it compares accuracy for BLUP, SNP ascertained data, sequence, and causal SNPs. It employs VanRaden's linear (GBLUP) and nonlinear method for incorporating molecular information. To illustrate the program, we present a small application in a half-sib population and a multiparental (MAGIC) cross. The program, manual and examples are available at https://github.com/mperezenciso/ms2gs. PMID:26995218

  11. Accidental explosions

    SciTech Connect

    Medard, L.A.

    1989-01-01

    This book presents a survey of accidental explosions, their nature and their causes. It covers the physical and chemical conditions governing accidental explosions, whether in the gas phase, or in the liquid or solid state. The theoretical background of the kinetics and thermochemistry of explosions is outlined, followed by a detailed study of the explosion and detonation properties of both gas and condensed explosives. The author surveys a wide variety of substances in daily use in industry which can give rise to accidental explosions. Their properties and hazards are spelt out in detail, the discussion drawing on a long history of sometimes catastrophic accidents. Includes case studies, tables of physical and chemical data.

  12. Elastic/Plastic Drop Analysis Using Finite Element Techniques

    SciTech Connect

    R. E. Spears

    1999-08-01

    A Spent Nuclear Fuel (SNF) can, which is called the High Integrity Can (HIC), is being designed at the Idaho National Engineering and Environmental Laboratory (INEEL). Its intended use is to contain SNF sent to the Idaho Nuclear Technology and Engineering Center (INTEC). INTEC will then do the final work with the HIC to send it to the repository at Yucca Mountain, Nevada, for long-term storage. One portion of the analysis, which was required for the HIC, was accidental drop scenarios. This consisted of 19 simulated drops from a height of 30-feet with impact on a flat rigid surface. Elastic/plastic analyses were performed for the simulated drops. Additionally, two elastic/plastic analyses were performed for drops from a height of 17-feet with impact on a rigid surface having a narrow raised portion across its center. The purpose of the analyses was to determine if any breach occurred which opened a crack wider than 0.05-inches from these drop scenarios. Also some plastic deformations were needed from certain drop scenarios to support the Criticality Safety documentation. The analytical results for the simulated drop scenarios showed that, though the seal in the lid may be broken, no 0.05-inch breach occurred. Also, the deformations for Criticality Safety documentation were calculated and show on the applicable output plots.

  13. Foot Drop

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Foot Drop Information Page Table of Contents (click to ... research is being done? Clinical Trials What is Foot Drop? Foot drop describes the inability to raise ...

  14. Accidental inflation in the landscape

    SciTech Connect

    Blanco-Pillado, Jose J.; Metallinos, Konstantinos; Gomez-Reino, Marta E-mail: marta.gomez-reino.perez@cern.ch

    2013-02-01

    We study some aspects of fine tuning in inflationary scenarios within string theory flux compactifications and, in particular, in models of accidental inflation. We investigate the possibility that the apparent fine-tuning of the low energy parameters of the theory needed to have inflation can be generically obtained by scanning the values of the fluxes over the landscape. Furthermore, we find that the existence of a landscape of eternal inflation in this model provides us with a natural theory of initial conditions for the inflationary period in our vacuum. We demonstrate how these two effects work in a small corner of the landscape associated with the complex structure of the Calabi-Yau manifold P{sup 4}{sub [1,1,1,6,9]} by numerically investigating the flux vacua of a reduced moduli space. This allows us to obtain the distribution of observable parameters for inflation in this mini-landscape directly from the fluxes.

  15. Severe Accidental Hypothermia Center.

    PubMed

    Darocha, Tomasz; Kosiński, Sylweriusz; Jarosz, Anna; Gałązkowski, Robert; Sadowski, Jerzy; Drwiła, Rafał

    2015-08-01

    Hypothermic patients may be rewarmed using passive or active techniques. In case of severe accidental hypothermia (temperature<28°C) and stage III/IV according to the Swiss Staging System, standard methods might not be effective and aggressive treatment is needed. Extracorporeal membrane oxygenation (ECMO) has proved to be both effective and safe in such cases. The Department of Anesthesiology and Intensive Care, John Paul II Hospital, Cracow, Poland, established the Severe Accidental Hypothermia Center, which provides 24 h on-call to consult and accept patients who need ECMO implantation for profound hypothermia rewarming. Our center is so far the only one in Poland and can accept patients from south-east Poland. Most importantly, it collaborates with all prehospital medical services, namely, with 115 Ambulances, Polish Medical Air Rescue, Mountain Rescue Services, and all 28 Emergency Departments in the area. Severe Accidental Hypothermia Center is a solution for advanced treatment of patients with accidental hypothermia requiring ECMO implantation. PMID:25304125

  16. Severe accidental dapsone overdose.

    PubMed

    McGoldrick, M D; Bailie, G R

    1995-07-01

    Acute poisoning from excessive dapsone (4,4-diaminodiphenylsulfone) intake in uncommon in the United States; no cases were reported during 1992. However, with the increasing use of dapsone for diseases other than leprosy and dermatitis herpetiformis, such as acne vulgaris, psoriasis, and Pneumocystis carinii pneumonia infection in acquired immunodeficiency syndrome, clinicians should be aware of potential toxicities. This report describes a case of accidental dapsone intoxication resulting in severe cyanosis with a modest elevation in methemoglobin concentration. PMID:7605525

  17. Drop dynamics

    NASA Technical Reports Server (NTRS)

    Elleman, D. D.

    1981-01-01

    The drop dynamics module is a Spacelab-compatible acoustic positioning and control system for conducting drop dynamics experiments in space. It consists basically of a chamber, a drop injector system, an acoustic positioning system, and a data collection system. The principal means of collecting data is by a cinegraphic camera. The drop is positioned in the center of the chamber by forces created by standing acoustic waves generated in the nearly cubical chamber (about 12 cm on a side). The drop can be spun or oscillated up to fission by varying the phse and amplitude of the acoustic waves. The system is designed to perform its experiments unattended, except for start-up and shutdown events and other unique events that require the attention of the Spacelab payload specialist.

  18. Accidental Khler moduli inflation

    NASA Astrophysics Data System (ADS)

    Maharana, Anshuman; Rummel, Markus; Sumitomo, Yoske

    2015-09-01

    We study a model of accidental inflation in type IIB string theory where inflation occurs near the inflection point of a small Khler modulus. A racetrack structure helps to alleviate the known concern that string-loop corrections may spoil Khler Moduli Inflation unless having a significant suppression via the string coupling or a special brane setup. Also, the hierarchy of gauge group ranks required for the separation between moduli stabilization and inflationary dynamics is relaxed. The relaxation becomes more significant when we use the recently proposed D-term generated racetrack model.

  19. Epidemiology of accidental radiation exposures.

    PubMed Central

    Cardis, E

    1996-01-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental radiation exposures, and discuss information that could be obtained from studies of accidental exposures and the types of studies that are needed. PMID:8781398

  20. The accidental (acoustical) tourist

    NASA Astrophysics Data System (ADS)

    Van Kirk, Wayne

    2002-11-01

    The acoustical phenomenon observed at an ancient temple in the Great Ball Court at Chichen Itza was described as ''little short of amazing--an ancient whispering gallery'' by Silvanus G. Morley, leader of the Carnegie Institute's archaeological team that excavated and restored these structures in the 1920s. Since then, many others have experienced the extraordinary acoustics at Chichen Itza and other Maya sites. Despite these reports, archaeologists and acousticians have until recently shown little interest in understanding these phenomena. After experiencing Chichen Itza's remarkable acoustics as a tourist in 1994, the author commenced collecting and disseminating information about acoustical phenomena there and at other Mayan sites, hoping to stimulate interest among archaeologists and acousticians. Were these designs accidental or intentional? If intentional, how was the knowledge obtained? How were acoustical features used? This paper highlights the author's collection of anecdotal reports of mysterious Mayan acoustics (http://http://www.ianlawton.com/pa1.htm), recommended reading for scientists and engineers who wish to pursue this fascinating study. Also recounted are some of the reactions of archaeologists-ranging from curious, helpful, and insightful to humorous and appalling--to outsiders' efforts to bring serious scientific attention to the new field of acoustical archaeology.

  1. Drop Testing Representative Multi-Canister Overpacks

    SciTech Connect

    Snow, Spencer D.; Morton, Dana K.

    2015-06-01

    The objective of the work reported herein was to determine the ability of the Multi- Canister Overpack (MCO) canister design to maintain its containment boundary after an accidental drop event. Two test MCO canisters were assembled at Hanford, prepared for testing at the Idaho National Engineering and Environmental Laboratory (INEEL), drop tested at Sandia National Laboratories, and evaluated back at the INEEL. In addition to the actual testing efforts, finite element plastic analysis techniques were used to make both pre-test and post-test predictions of the test MCOs structural deformations. The completed effort has demonstrated that the canister design is capable of maintaining a 50 psig pressure boundary after drop testing. Based on helium leak testing methods, one test MCO was determined to have a leakage rate not greater than 1x10-5 std cc/sec (prior internal helium presence prevented a more rigorous test) and the remaining test MCO had a measured leakage rate less than 1x10-7 std cc/sec (i.e., a leaktight containment) after the drop test. The effort has also demonstrated the capability of finite element methods using plastic analysis techniques to accurately predict the structural deformations of canisters subjected to an accidental drop event.

  2. Epidemiology of accidental radiation exposures

    SciTech Connect

    Cardis, E.

    1996-05-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental exposures and the types of studies that are needed. 64 refs., 3 tabs.

  3. Accidental death in autoerotic maneuvers.

    PubMed

    Focardi, Martina; Gualco, Barbara; Norelli, GianAristide

    2008-03-01

    The authors from the Florence Forensic Department present a case that demonstrates the paradigms attached to accidental deaths while performing autoerotic maneuvers. The incidents of such practices are underestimated and are only the tip of the iceberg since they do not represent the cases that are never reported due to successful practice. After analyzing the statistic data, the authors describe the case and discuss about the element that prove the accidental nature of the death and the importance of the correct application of forensic methodology at the scene and in the mortuary. PMID:19749620

  4. Dilating Eye Drops

    MedlinePlus

    ... Frequently Asked Questions Español Condiciones Chinese Conditions Dilating Eye Drops En Español Read in Chinese What are dilating eye drops? Dilating eye drops contain medication to enlarge ( ...

  5. Why Chalk Breaks into Three Pieces When Dropped

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    It has been the author's experience over many years, no doubt shared by others, that a stick of chalk usually breaks into three pieces when accidentally dropped onto the floor. I rarely gave it any thought, apart from noting that the fundamental mode of vibration of a freely supported, rigid rod has two nodes at an equal distance from each

  6. Why Chalk Breaks into Three Pieces When Dropped

    ERIC Educational Resources Information Center

    Cross, Rod

    2015-01-01

    It has been the author's experience over many years, no doubt shared by others, that a stick of chalk usually breaks into three pieces when accidentally dropped onto the floor. I rarely gave it any thought, apart from noting that the fundamental mode of vibration of a freely supported, rigid rod has two nodes at an equal distance from each…

  7. A Different Cone: Bursting Drops in Solids

    NASA Astrophysics Data System (ADS)

    Zhao, Xuanhe

    2013-03-01

    Drops in fluids tend to be spheres--a shape that minimizes surface energy. In thunderstorm clouds, drops can become unstable and emit thin jets when charged beyond certain limits. The instability of electrified drops in gases and liquids has been widely studied and used in applications including ink-jet printing, electrospinning nano-fibers, microfluidics and electrospray ionization. Here we report a different scenario: drops in solids become unstable and burst under sufficiently high electric fields. We find the instability of drops in solids morphologically resembles that in liquids, but the critical electric field for the instability follows a different scaling due to elasticity of solids. Our observations and theoretical models not only advance the fundamental understanding of electrified drops but also suggest a new failure mechanism of high-energy-density dielectric polymers, which have diverse applications ranging from capacitors for power grids and electric vehicles to muscle-like transducers for soft robots and energy harvesting.

  8. Momentumless coalescence of drops

    NASA Technical Reports Server (NTRS)

    Anilkumar, A. V.; Lee, C. P.; Wang, Taylor G.

    1992-01-01

    The dynamics of mixing and satellite drop formation following the coalescence of initially stationary low-viscosity drops of the same liquid has been investigated using immiscible systems. The main parameters of interest are the drop sizes, the drop viscosity and the host viscosity. For drops of equal sizes there is no mixing following coalescence, which is consistent with that first demonstrated on the Skylab. However, for drops of unequal sizes there is considerable mixing with the smaller drop penetrating the larger drop as a vortex. In the extreme case of coalescence of a small drop with the bulk of the same liquid at a flat interface, the measured penetration depth is found to be proportional to the 5/4 th power of the drop diameter and inversely proportional to the square root of drop viscosity. When the drop and host viscosities are comparable, drop penetration is prematurely terminated by the formation of a satellite drop. However, when the drop diameter ratio (large to small) is below a critical number, satellite drop formation is inhibited and coalescence goes to completion. The influence of drop-host viscosity ratio on this critical diameter ratio has been examined.

  9. Investigation of Thermal Equilibrium around an Accidental Event and Impact on Possibly Enclosed Surrounding Environment

    NASA Astrophysics Data System (ADS)

    Sarkar, Biswanath; Shah, Nitin; Choukekar, Ketan; Kapoor, Himanshu; Kumar, Uday; Das, Jotirmoy; Bhattacharaya, Ritendra; Vaghela, Hitensinh; Muralidhara, Srinivasa

    Complex and large cryogenic distribution systems are integral part of a fusion machine having superconducting magnets, cryopumps, etc. The various equipment of the cryogenic distribution system are interconnected via Cryogenic Transfer Lines (CTLs) to distribute cold helium to end users. During nominal operation of the fusion machine, helium inventory in CTLs could be in order of several tons. The cold helium present in CTLs could be released in surrounding volume due to accidental scenario. The present analysis, aims to estimate lowest temperature in the surrounding volume due to accidental scenario. The paper will describe simulation results and the test plan in a simulated condition.

  10. Science Scenarios.

    ERIC Educational Resources Information Center

    Cronin-Jones, Linda

    2000-01-01

    Focuses on using science-related issues in classrooms. Explains how to select these issues and create a scenario, and presents a sample scenario for a role-playing activity. Provides several format structures for role-plays. (YDS)

  11. Alternate drop pulse polarography

    USGS Publications Warehouse

    Christie, J.H.; Jackson, L.L.; Osteryoung, R.A.

    1976-01-01

    The new technique of alternate drop pulse polarography is presented. An experimental evaluation of alternate drop pulse polarography shows complete compensation of the capacitative background due to drop expansion. The capillary response phenomenon was studied in the absence of faradaic reaction and the capillary response current was found to depend on the pulse width to the -0.72 power. Increased signal-to-noise ratios were obtained using alternate drop pulse polarography at shorter drop times.

  12. Dark scenarios

    NASA Astrophysics Data System (ADS)

    Ahonen, Pasi; Alahuhta, Petteri; Daskala, Barbara; Delaitre, Sabine; Hert, Paul De; Lindner, Ralf; Maghiros, Ioannis; Moscibroda, Anna; Schreurs, Wim; Verlinden, Michiel

    In this chapter, we present four "dark scenarios" that highlight the key socio-economic, legal, technological and ethical risks to privacy, identity, trust, security and inclusiveness posed by new AmI technologies. We call them dark scenarios, because they show things that could go wrong in an AmI world, because they present visions of the future that we do not want to become reality. The scenarios expose threats and vulnerabilities as a way to inform policy-makers and planners about issues they need to take into account in developing new policies or updating existing legislation. Before presenting the four scenarios and our analysis of each, we describe the process of how we created the scenarios as well as the elements in our methodology for analysing the scenarios.

  13. Ternary drop collisions

    NASA Astrophysics Data System (ADS)

    Hinterbichler, Hannes; Planchette, Carole; Brenn, Günter

    2015-10-01

    It has been recently proposed to use drop collisions for producing advanced particles or well-defined capsules, or to perform chemical reactions where the merged drops constitute a micro-reactor. For all these promising applications, it is essential to determine whether the merged drops remain stable after the collision, forming a single entity, or if they break up. This topic, widely investigated for binary drop collisions of miscible and immiscible liquid, is quite unexplored for ternary drop collisions. The current study aims to close this gap by experimentally investigating collisions between three equal-sized drops of the same liquid arranged centri-symmetrically. Three drop generators are simultaneously operated to obtain controlled ternary drop collisions. The collision outcomes are observed via photographs and compared to those of binary collisions. Similar to binary collisions, a regime map is built, showing coalescence and bouncing as well as reflexive and stretching separation. Significant differences are observed in the transitions between these regimes.

  14. Eye Drop Tips

    MedlinePlus

    ... Involved News About Us Donate In This Section Eye Drop Tips en Español email Send this article ... the reach of children. Steps For Putting In Eye Drops: Start by tilting your head backward while ...

  15. Accidental decapitation: a case report.

    PubMed

    Demirci, Serafettin; Dogan, Kamil Hakan; Erkol, Zerrin; Gunaydin, Gursel

    2009-09-01

    We report a case of an accidental decapitation of an agriculture worker in a field. The scene investigation revealed that the worker had loosely tied a scarf tied over his face in an attempt to diminish his exposure to barley dust, to which he was allergic, while distributing the barley loads with a shovel upon a trailer. The trailer was simultaneously being loaded by a helix elevator machine and its rotating shaft suddenly caught the victim's scarf and pulled it down to the victim's neck. The rotating motion immediately tightened the scarf around the neck resulting in hanging/strangulation noose that, by continued tightening, caused decapitation of the victim. The victim's body was found on the ground by the trailer and the victim's head was discovered in the barley load in the trailer. Examination revealed that the neck was severed at the level of the second and third cervical vertebrae. PMID:19696584

  16. Non-accidental salt poisoning.

    PubMed Central

    Meadow, R

    1993-01-01

    The clinical features of 12 children who incurred non-accidental salt poisoning are reported. The children usually presented to hospital in the first six months of life with unexplained hypernatraemia and associated illness. Most of the children suffered repetitive poisoning before detection. The perpetrator was believed to the mother for 10 children, the father for one, and either parent for one. Four children had serum sodium concentrations above 200 mmol/l. Seven children had incurred other fabricated illness, drug ingestion, physical abuse, or failure to thrive/neglect. Two children died; the other 10 remained healthy in alternative care. Features are described that should lead to earlier detection of salt poisoning; the importance of checking urine sodium excretion, whenever hypernatraemia occurs, is stressed. PMID:8503665

  17. Is the tribimaximal mixing accidental?

    SciTech Connect

    Abbas, Mohammed; Smirnov, A. Yu.

    2010-07-01

    The tribimaximal (TBM) mixing is not accidental if structures of the corresponding leptonic mass matrices follow immediately from certain (residual or broken) flavor symmetry. We develop a simple formalism which allows one to analyze effects of deviations of the lepton mixing from TBM on the structure of the neutrino mass matrix and on the underlying flavor symmetry. We show that possible deviations from the TBM mixing can lead to strong modifications of the mass matrix and strong violation of the TBM-mass relations. As a result, the mass matrix may have an 'anarchical' structure with random values of elements or it may have some symmetry that differs from the TBM symmetry. Interesting examples include matrices with texture zeros, matrices with certain 'flavor alignment' as well as hierarchical matrices with a two-component structure, where the dominant and subdominant contributions have different symmetries. This opens up new approaches to understanding the lepton mixing.

  18. Graphical Drop Caps Indexing

    NASA Astrophysics Data System (ADS)

    Chouaib, Hassan; Cloppet, Florence; Vincent, Nicole

    This paper presents a method for graphical drop caps indexing. Drop caps are extracted from old books. Finding a method classifying them according to styles defined by the historian is of considerable interest. The developed method is a statistical approach, where all possible patterns included in a pixel mask are processed in order to extract indexes that characterize the image. Then these indexes are used to classify a query drop cap by searching its most similar drop caps in the indexed base.

  19. Drop coalescence studies

    NASA Technical Reports Server (NTRS)

    Anikumar, A. V.; Wang, T. G.

    1990-01-01

    The objective of this experimental study is to understand the detailed mechanics of the coalescence of liquid drops. The experiments are being conducted in an immiscible acoustic levitator with degassed water as the host medium. Typically, a quasineutrally buoyant drop of silicon oil mixed with bromobenzene is levitated close to the velocity node of the levitator. A second drop of the same liquid is introduced, and as it slowly seeks levitation position, the drops coalesce. Coalescence is delayed until the host film between drops is completely drained. Following coalescence, the excess surface energy in the coalesced drop is dissipated through shape oscillations. The final events of film rupture followed by drop coalescence are rapid and are photographically studied with high-speed video (1000 fps). The laser-induced fluorescence technique is used to visualize the dynamics of host film drainage. The details of the coalescence mechanics are presented.

  20. Modeling downwind hazards after an accidental release of chlorine trifluoride

    SciTech Connect

    Lombardi, D.A.; Cheng, Meng-Dawn

    1996-05-01

    A module simulating ClF{sub 3} chemical reactions with water vapor and thermodynamic processes in the atmosphere after an accidental release has been developed. This module was liked to the HGSYSTEM. Initial model runs simulate the rapid formation of HF and ClO{sub 2} after an atmospheric release of ClF{sub 3}. At distances beyond the first several meters from the release point, HF and ClO{sub 2} concentrations pose a greater threat to human health than do ClF{sub 3} concentrations. For most of the simulations, ClF{sub 3} concentrations rapidly fall below the IDLH. Fro releases occurring in ambient conditions with low relative humidity and/or ambient temperature, ClF{sub 3} concentrations exceed the IDLH up to almost 500 m. The performance of this model needs to be determined for potential release scenarios that will be considered. These release scenarios are currently being developed.

  1. The characterization and evaluation of accidental explosions

    NASA Technical Reports Server (NTRS)

    Strehlow, R. A.; Baker, W. E.

    1975-01-01

    Accidental explosions are discussed from a number of viewpoints. First, all accidental explosions, intentional explosions and natural explosions are characterized by type. Second, the nature of the blast wave produced by an ideal (point source or HE) explosion is discussed to form a basis for describing how other explosion processes yield deviations from ideal blast wave behavior. The current status blast damage mechanism evaluation is also discussed. Third, the current status of our understanding of each different category of accidental explosions is discussed in some detail.

  2. Accidental death involving professional fireworks.

    PubMed

    Romolo, Francesco Saverio; Aromatario, Mariarosaria; Bottoni, Edoardo; Cappelletti, Simone; Fiore, Paola Antonella; Ciallella, Costantino

    2014-01-01

    An interesting case of accidental death involving the explosion of professional fireworks in an apartment is described. The examination of the scene permitted to study several effects of the explosion on walls, ceiling, furniture and especially on a balcony where the victim was found. The external examination of the victim showed extensive thermal injuries, degloving injuries and extensive shrapnel wounds. The autopsy examination showed subarachnoid haemorrhage localized to the cerebellum, haemorrhage in the soft tissues of the neck and chest and fracture of one clavicle. Almost the entire surface of lungs showed blunt injuries and the liver showed tearing of parenchyma and multiple cavities. Histological analysis were carried out showing thickening of alveolar septae, enlargement of alveolar spaces and alveolar ruptures in lung sections while numerous, round, empty spaces were detected in the parenchyma of the liver. The examination of the scene and of the fragments found showed that at least eight pyrotechnical charges exploded on the balcony, in close proximity of the threshold with the living room of the apartment. According to the chemical findings, the charges were typical for professional use and were filled with a mixture of potassium perchlorate and aluminium. A conservative calculation results in more than 1.5 kg total mass of pyrotechnic composition exploding very close to the victim. PMID:24279979

  3. Simulations of accidental coal immersion.

    PubMed

    Jaffrennou, Cathy; Giamarchi, Philippe; Cabon, Jean-Yves; Stephan, Ludovic; Burel-Deschamps, Laure; Bautin, François; Thomas, Annabelle; Dumont, Julien; Le Floch, Stéphane

    2007-12-01

    Coal is currently becoming an increasingly interesting fossil energy resource and that is the reason why its maritime transport, and hence the risk of collier accidents, increase. In this work, the environmental impact of an accidental coal immersion at sea is studied: the physicochemical effects are estimated using innovative experimental setups--a laboratory seawater canal called "polludrome" is used to evaluate the behaviour of coal particles submitted to a seawater flow, and a specifically designed tub is used to study the physicochemical consequences induced when coal is introduced into continuously renewed seawater. When coal is introduced into seawater, the most easily visible consequences are physical: fine coal particles reduce the daylight penetration up to 100% and move along with the flow, and coal chunks accumulate on the floor. Chemical effects are also measured: humic matters are dissolved from coal into seawater (up to 2 mg L(-1)), but no release of polycyclic aromatic hydrocarbons is evidenced. Some inorganic compounds are dissolved, among which manganese, whose concentrations can reach 1 microg L(-1). Fortunately, the results show that the environmental impact of this type of accident would remain limited. PMID:17964611

  4. Drag on Sessile Drops

    NASA Astrophysics Data System (ADS)

    Milne, Andrew J. B.; Fleck, Brian; Nobes, David; Sen, Debjyoti; Amirfazli, Alidad; University of Alberta Mechanical Engineering Collaboration

    2013-11-01

    We present the first ever direct measurements of the coefficient of drag on sessile drops at Reynolds numbers from the creeping flow regime up to the point of incipient motion, made using a newly developed floating element differential drag sensor. Surfaces of different wettabilities (PMMA, Teflon, and a superhydrophobic surface (SHS)), wet by water, hexadecane, and various silicone oils, are used to study the effects of drop shape, and fluid properties on drag. The relation between drag coefficient and Reynolds number (scaled by drop height) varies slightly with liquid-solid system and drop volume with results suggesting the drop experiences increased drag compared to similar shaped solid bodies due to drop oscillation influencing the otherwise laminar flow. Drops adopting more spherical shapes are seen to experience the greatest force at any given airspeed. This indicates that the relative exposed areas of drops is an important consideration in terms of force, with implications for the shedding of drops in applications such as airfoil icing and fuel cell flooding. The measurement technique used in this work can be adapted to measure drag force on other deformable, lightly adhered objects such as dust, sand, snow, vesicles, foams, and biofilms. The authours acknowledge NSERC, Alberta Innovates Technology Futures, and the Killam Trusts.

  5. An accidental poisoning with mitragynine.

    PubMed

    Karinen, Ritva; Fosen, Jan Toralf; Rogde, Sidsel; Vindenes, Vigdis

    2014-10-24

    An increasing number of drugs of abuse are sold word wide over the internet. Names like "legal highs", "herbal highs" etc. give the impression that these are safe products, although the risk of fatal reactions might be substantial. Leaves from the plant Mitragyna speciosa, contain active compounds like mitragynine and 7-hydroxymitragynine. It has been reported that the potency of 7-hydroxymitragynine at the μ-opioid receptor is 30 times higher than that of mitragynine and 17 times higher than that of morphine. Case reports regarding poisoning with Kratom are reported, but the toxic or lethal ranges for the concentrations of the active substances have not been established, and concentrations of 7-hydroxymitragynine have not been reported previously. We present a case report where a middle aged man was found dead at home. The deceased had a history of drug abuse and mental illness for several years. At autopsy, there were no significant pathological findings. Post-mortem analysis of peripheral blood revealed: zopiclone 0.043mg/L, citalopram 0.36mg/L and lamotrigine 5.4mg/L, i.e. concentrations regularly seen after therapeutic ingestion of these drugs. Additionally mitragynine 1.06mg/L and 7-hydroxymitragynine 0.15mg/L were detected in blood and both also in urine. The high concentrations of mitragynine and 7-hydroxymitragynine indicate that the cause of death is intoxication by these substances; and the circumstances point toward the manner of death being accidental. We recommend that both mitragynine and 7-hydroxymitragynine are analyzed for in cases with suspected Kratom intoxication. PMID:25453780

  6. Axisymmetric Liquid Hanging Drops

    ERIC Educational Resources Information Center

    Meister, Erich C.; Latychevskaia, Tatiana Yu

    2006-01-01

    The geometry of drops hanging on a circular capillary can be determined by numerically solving a dimensionless differential equation that is independent on any material properties, which enables one to follow the change of the height, surface area, and contact angle of drops hanging on a particular capillary. The results show that the application…

  7. Drop Tower Physics

    ERIC Educational Resources Information Center

    Dittrich, William A.

    2014-01-01

    The drop towers of yesteryear were used to make lead shot for muskets, as described in "The Physics Teacher" in April 2012. However, modern drop towers are essentially elevators designed so that the cable can "break" on demand, creating an environment with microgravity for a short period of time, currently up to nine seconds at…

  8. Youth Crime Drop. Report.

    ERIC Educational Resources Information Center

    Butts, Jeffrey A.

    This report examines the recent drop in violent crime in the United States, discussing how much of the decrease seen between 1995-99 is attributable to juveniles (under age 18 years) and older youth (18-24 years). Analysis of current FBI arrest data indicates that not only did America's violent crime drop continue through 1999, but falling youth…

  9. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  10. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  11. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  12. 5 CFR 870.206 - Accidental death and dismemberment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Accidental death and dismemberment. 870....206 Accidental death and dismemberment. (a)(1) Accidental death and dismemberment coverage is an automatic part of Basic and Option A insurance for employees. (2) There is no accidental death...

  13. Drop Tower Physics

    NASA Astrophysics Data System (ADS)

    Dittrich, William A. Toby

    2014-10-01

    The drop towers of yesteryear were used to make lead shot for muskets, as described in The Physics Teacher1 in April 2012. However, modern drop towers are essentially elevators designed so that the cable can "break" on demand, creating an environment with microgravity for a short period of time, currently up to nine seconds at the drop tower in Bremen, Germany. Using these drop towers, one can briefly investigate various physical systems operating in this near zero-g environment. The resulting "Drop Tower Physics" is a new and exciting way to challenge students with a physical example that requires solid knowledge of many basic physics principles, and it forces them to practice the scientific method. The question is, "How would a simple toy, like a pendulum, behave when it is suddenly exposed to a zero-g environment?" The student must then postulate a particular behavior, test the hypothesis against physical principles, and if the hypothesis conforms to these chosen physical laws, the student can formulate a final conclusion. At that point having access to a drop tower is very convenient, in that the student can then experimentally test his or her conclusion. The purpose of this discussion is to explain the response of these physical systems ("toys") when the transition is made to a zero-g environment and to provide video demonstrations of this behavior to support in-class discussions of Drop Tower Physics.

  14. Drop impact of suspensions

    NASA Astrophysics Data System (ADS)

    Thoraval, M.-J.; Boyer, F.; Sandoval Nava, E.; Dijksman, J. F.; Lohse, D.; Snoeijer, J. H.

    2014-11-01

    Drop impact studies have a wide range of applications, many of which involve complex fluids. We study here the liquid drop impact of a silver nano-particles dispersion on a solid glass surface. This dispersion is used for inkjet printing of functional electronic materials. When the impact velocity increases, the drop classically splashes into smaller droplets. However, it surprisingly stops splashing above a critical impact velocity. We combine high-speed imaging experiments with different characterizations of the dispersion to understand this transition to non-splashing.

  15. Inverse Leidenfrost Effect: Levitating Drops on Liquid Nitrogen.

    PubMed

    Adda-Bedia, M; Kumar, S; Lechenault, F; Moulinet, S; Schillaci, M; Vella, D

    2016-05-01

    We explore the interaction between a liquid drop (initially at room temperature) and a bath of liquid nitrogen. In this scenario, heat transfer occurs through film-boiling: a nitrogen vapor layer develops that may cause the drop to levitate at the bath surface. We report the phenomenology of this inverse Leidenfrost effect, investigating the effect of the drop size and density by using an aqueous solution of a tungsten salt to vary the drop density. We find that (depending on its size and density) a drop either levitates or instantaneously sinks into the bulk nitrogen. We begin by measuring the duration of the levitation as a function of the radius R and density ρd of the liquid drop. We find that the levitation time increases roughly linearly with drop radius but depends weakly on the drop density. However, for sufficiently large drops, R ≥ Rc(ρd), the drop sinks instantaneously; levitation does not occur. This sinking of a (relatively) hot droplet induces film-boiling, releasing a stream of vapor bubbles for a well-defined length of time. We study the duration of this immersed-drop bubbling finding similar scalings (but with different prefactors) to the levitating drop case. With these observations, we study the physical factors limiting the levitation and immersed-film-boiling times, proposing a simple model that explains the scalings observed for the duration of these phenomena, as well as the boundary of (R,ρd) parameter space that separates them. PMID:27054550

  16. Drop Tower Workshop

    NASA Technical Reports Server (NTRS)

    Urban, David

    2013-01-01

    Ground based microgravity facilities are an important proving ground for space experiments, ground-based research and space hardware risk mitigation. An overview of existing platforms will be discussed with an emphasis on drop tower capabilities. The potential for extension to partial gravity conditions will be discussed. Input will be solicited from attendees for their potential to use drop towers in the future and the need for enhanced capabilities (e.g. partial gravity)

  17. Evolution Towards Critical Fluctuations in a System of Accidental Pathogens

    NASA Astrophysics Data System (ADS)

    Ghaffari, Peyman; Jansen, Vincent; Stollenwerk, Nico

    2011-09-01

    Some time ago a model for accidental pathogens was developed to describe large fluctuations in the epidemiology of some diseases where the pathogen mostly lives with its host as a commensal and only rarely causes disease, leading to a disadvantage of the mutants which cause disease more often. By now the simplest version of this scenario is known as Stollenwerk-Jansen (SJ) model, showing that the critical exponents of the large fluctuations are of the type of the voter model (which by itself has an evolutionary biologists predecessor) but no further attempt was made there to investigate in more detail the mechanism leading the system to evolve towards small pathogenicity. We investigate an extended version of the SJ model, the SJ model version II in which we find the system to evolve to low pathogenicity causing large critical fluctuations without tuning the control parameter, a self-organization of criticality.

  18. Two accidental hanging cases of children.

    PubMed

    Gok, Ertugrul; Cetin, Selcuk; Baduroglu, Erol; Fedakar, Recep; Akan, Okan; Saka, Naile Esra

    2015-07-01

    The cases emphasise the implementation of safety measurements which may prevent the occurrence of accidental hanging in children. Two accidental hanging cases were autopsied at The Council of Forensic Medicine, Bursa Group Chairmanship, Morgue Department. The inquest papers written by police were examined and the scenes and autopsy findings are presented. The first case was a four year old girl and the second case was a five year old boy. Their manners of death were determined as an accident. The first accident occurred out of home, but the second accidental hanging occurred at home. It was seen that childhood deaths due to hanging are preventable. Detailed medico-legal investigation in order to elucidate the manner of death is required in similar cases. PMID:26160094

  19. Deep accidental hypothermia during the Queensland summer.

    PubMed

    Udy, Andrew A; Ziegenfuss, Marc D; Fraser, John F

    2007-12-01

    A 52-year-old woman presented with severe accidental hypothermia associated with out-of-hospital cardiac arrest after a polypharmacy overdose. Deep hypothermia developed while she lay unconscious, with a split-system air-conditioning unit rapidly cooling the confined area of her bedroom. Despite the need for lengthy resuscitative efforts at the scene and in hospital, she went on to a full neurological recovery. The neuroprotective role of accidental hypothermia is reviewed, as are the guidelines for resuscitation in this setting. We conclude that hypothermia must be considered even in unlikely circumstances, such as the Queensland summer, when ambient temperatures are high. PMID:18052898

  20. Rain Drop Charge Sensor

    NASA Astrophysics Data System (ADS)

    S, Sreekanth T.

    begin{center} Large Large Rain Drop Charge Sensor Sreekanth T S*, Suby Symon*, G. Mohan Kumar (1) , S. Murali Das (2) *Atmospheric Sciences Division, Centre for Earth Science Studies, Thiruvananthapuram 695011 (1) D-330, Swathi Nagar, West Fort, Thiruvananthapuram 695023 (2) Kavyam, Manacaud, Thiruvananthapuram 695009 begin{center} ABSTRACT To study the inter-relations with precipitation electricity and precipitation microphysical parameters a rain drop charge sensor was designed and developed at CESS Electronics & Instrumentation Laboratory. Simultaneous measurement of electric charge and fall speed of rain drops could be done using this charge sensor. A cylindrical metal tube (sensor tube) of 30 cm length is placed inside another thick metal cover opened at top and bottom for electromagnetic shielding. Mouth of the sensor tube is exposed and bottom part is covered with metal net in the shielding cover. The instrument is designed in such a way that rain drops can pass only through unhindered inside the sensor tube. When electrically charged rain drops pass through the sensor tube, it is charged to the same magnitude of drop charge but with opposite polarity. The sensor tube is electrically connected the inverted input of a current to voltage converter operational amplifier using op-amp AD549. Since the sensor is electrically connected to the virtual ground of the op-amp, the charge flows to the ground and the generated current is converted to amplified voltage. This output voltage is recorded using a high frequency (1kHz) voltage recorder. From the recorded pulse, charge magnitude, polarity and fall speed of rain drop are calculated. From the fall speed drop diameter also can be calculated. The prototype is now under test running at CESS campus. As the magnitude of charge in rain drops is an indication of accumulated charge in clouds in lightning, this instrument has potential application in the field of risk and disaster management. By knowing the charge magnitude of initial drops from a precipitation event, gross cloud charge can be estimated and necessary precautions can be taken during convective cloud events. Being a site of high lightning incidence in tropics, Kerala state is affected in India and calls for much attention in lightning hazards mitigation. Installing this charge sensor and atmospheric electric field mill, an attempt to a better warning system can be attempted.

  1. Liquid metal drop ejection

    NASA Technical Reports Server (NTRS)

    Khuri-Yakub, B. T.

    1993-01-01

    The aim of this project was to demonstrate the possibility of ejecting liquid metals using drop on demand printing technology. The plan was to make transducers for operation in the 100 MHz frequency range and to use these transducers to demonstrate the ability to eject drops of liquid metals such as gallium. Two transducers were made by indium bonding piezoelectric lithium niobate to quartz buffer rods. The lithium niobate plates were thinned by mechanical polishing to a thickness of 37 microns for operation at 100 MHz. Hemispherical lenses were polished in the opposite ends of the buffer rods. The lenses, which focus the sound waves in the liquid metal, had an F-number equals 1. A mechanical housing was made to hold the transducers and to allow precise control over the liquid level above the lens. We started by demonstrating the ability to eject drops of water on demand. The drops of water had a diameter of 15 microns which corresponds to the wavelength of the sound wave in the water. A videotape of this ejection was made. We then used a mixture of Gallium and Indium (used to lower the melting temperature of the Gallium) to demonstrate the ejection of liquid metal drops. This proved to be difficult because of the oxide skin which forms on the surface of the liquid. In some instances, we were able to eject metal drops, however, this was not consistent and reproducible. An experiment was set up at NASA-Lewis to stabilize the process of drop on demand liquid metal ejection. The object was to place the transducer and liquid metal in a vacuum station so that no oxide would form on the surface. We were successful in demonstrating that liquid metals could be ejected on demand and that this technology could be used for making sheet metal in space.

  2. Drying drops of blood

    NASA Astrophysics Data System (ADS)

    Brutin, David; Sobac, Benjamin; Loquet, Boris; Sampol, José.

    2010-11-01

    The drying of a drop of human blood is fascinating by the complexity of the physical mechanisms that occur as well as the beauty of the phenomenon which has never been previously evidenced in the literature. The final stage of full blood evaporation reveals for a healthy person the same regular pattern with a good reproducibility. Other tests on anemia and hyperlipidemic persons were performed and presented different patterns. By means of digital camera, the influence of the motion of red blood cells (RBCs) which represent about 50% of the blood volume, is revealed as well as its consequences on the final stages of drying. The mechanisms which lead to the final pattern of dried blood drops are presented and explained on the basis of fluid and solid mechanics in conjunction with the principles of hematology. Our group is the first to evidence that the specific regular patterns characteristic of a healthy individual do not appear in a dried drop of blood from a person with blood disease. Blood is a complex colloidal suspension for which the flow motion is clearly non-Newtonian. When drops of blood evaporate, all the colloids are carried by the flow motion inside the drop and interact.

  3. Bursting drops in solid dielectrics caused by high voltages

    NASA Astrophysics Data System (ADS)

    Wang, Qiming; Suo, Zhigang; Zhao, Xuanhe

    2012-10-01

    Fluid drops tend to be spheres—a shape that minimizes surface energy. In thunderstorm clouds, drops can become unstable and emit thin jets when charged beyond certain limits. The instability of electrified drops in gases and liquids has been widely studied and used in applications including ink-jet printing, electrospinning nanofibers, microfluidics and electrospray ionization. Here we report a different scenario: drops in solids become unstable and burst under sufficiently high electric fields. We find the instability of drops in solids morphologically resembles that in liquids, but the critical electric field for the instability follows a different scaling due to elasticity of solids. Our observations and theoretical models not only advance the fundamental understanding of electrified drops, but also suggest a new failure mechanism of high energy density dielectric polymers, which have diverse applications ranging from capacitors for power grids and electric vehicles to muscle-like transducers for soft robots and energy harvesting.

  4. Bursting drops in solid dielectrics caused by high voltages.

    PubMed

    Wang, Qiming; Suo, Zhigang; Zhao, Xuanhe

    2012-01-01

    Fluid drops tend to be spheres--a shape that minimizes surface energy. In thunderstorm clouds, drops can become unstable and emit thin jets when charged beyond certain limits. The instability of electrified drops in gases and liquids has been widely studied and used in applications including ink-jet printing, electrospinning nanofibers, microfluidics and electrospray ionization. Here we report a different scenario: drops in solids become unstable and burst under sufficiently high electric fields. We find the instability of drops in solids morphologically resembles that in liquids, but the critical electric field for the instability follows a different scaling due to elasticity of solids. Our observations and theoretical models not only advance the fundamental understanding of electrified drops, but also suggest a new failure mechanism of high energy density dielectric polymers, which have diverse applications ranging from capacitors for power grids and electric vehicles to muscle-like transducers for soft robots and energy harvesting. PMID:23093194

  5. Bursting Drops in Solid Dielectrics Caused by High Voltages

    PubMed Central

    Wang, Qiming; Suo, Zhigang

    2013-01-01

    Drops in fluids tend to be spheres—a shape that minimizes surface energy. In thunderstorm clouds, drops can become unstable and emit thin jets when charged beyond certain limits. The instability of electrified drops in gases and liquids has been widely studied and used in applications including ink-jet printing, electrospinning nano-fibers, microfluidics and electrospray ionization. Here we report a different scenario: drops in solids become unstable and burst under sufficiently high electric fields. We find the instability of drops in solids morphologically resembles that in liquids, but the critical electric field for the instability follows a different scaling due to elasticity of solids. Our observations and theoretical models not only advance the fundamental understanding of electrified drops but also suggest a new failure mechanism of high-energy-density dielectric polymers, which have diverse applications ranging from capacitors for power grids and electric vehicles to muscle-like transducers for soft robots and energy harvesting. PMID:23093194

  6. How do drops evaporate?

    NASA Astrophysics Data System (ADS)

    Murisic, Nebojsa; Kondic, Lou

    2007-11-01

    The problem of evaporating drops with non-pinned contact line, although seemingly trivial, so far lacks satisfactory theoretical description. In particular, there has been much discussion regarding appropriate evaporative mass flux model. We make an attempt to resolve this issue by comparing our experimental data with the results of several mathematical models for evaporating drops. After describing experimental procedure, we propose several models for mass flux and develop a governing equation for evolution of drop's thickness. Two-dimensional numerical results are then compared to the experimental results, and the most appropriate mass flux model is identified. Finally, we propose the governing equation for the full 3D system and present some new numerical results related to curious phenomena, where so-called ``octopus-shaped'' instabilities appear ahead of the contact line of volatile dropsootnotetextY. Gotkis, I. Ivanov, N. Murisic, L. Kondic, Phys. Rev. Lett. 97, 186101 (2006)..

  7. Impact of granular drops.

    PubMed

    Marston, J O; Mansoor, M M; Thoroddsen, S T

    2013-07-01

    We investigate the spreading and splashing of granular drops during impact with a solid target. The granular drops are formed from roughly spherical balls of sand mixed with water, which is used as a binder to hold the ball together during free-fall. We measure the instantaneous spread diameter for different impact speeds and find that the normalized spread diameter d/D grows as (tV/D)(1/2). The speeds of the grains ejected during the "splash" are measured and they rarely exceed twice that of the impact speed. PMID:23944390

  8. Do-It-Yourself device for recovery of cryopreserved samples accidentally dropped into cryogenic storage tanks.

    PubMed

    Mehta, Rohini; Baranova, Ancha; Birerdinc, Aybike

    2012-01-01

    Liquid nitrogen is colorless, odorless, extremely cold (-196 °C) liquid kept under pressure. It is commonly used as a cryogenic fluid for long term storage of biological materials such as blood, cells and tissues (1,2). The cryogenic nature of liquid nitrogen, while ideal for sample preservation, can cause rapid freezing of live tissues on contact - known as 'cryogenic burn' (2), which may lead to severe frostbite in persons closely involved in storage and retrieval of samples from Dewars. Additionally, as liquid nitrogen evaporates it reduces the oxygen concentration in the air and might cause asphyxia, especially in confined spaces (2). In laboratories, biological samples are often stored in cryovials or cryoboxes stacked in stainless steel racks within the Dewar tanks (1). These storage racks are provided with a long shaft to prevent boxes from slipping out from the racks and into the bottom of Dewars during routine handling. All too often, however, boxes or vials with precious samples slip out and sink to the bottom of liquid nitrogen filled tank. In such cases, samples could be tediously retrieved after transferring the liquid nitrogen into a spare container or discarding it. The boxes and vials can then be relatively safely recovered from emptied Dewar. However, the cryogenic nature of liquid nitrogen and its expansion rate makes sunken sample retrieval hazardous. It is commonly recommended by Safety Offices that sample retrieval be never carried out by a single person. Another alternative is to use commercially available cool grabbers or tongs to pull out the vials (3). However, limited visibility within the dark liquid filled Dewars poses a major limitation in their use. In this article, we describe the construction of a Cryotolerant DIY retrieval device, which makes sample retrieval from Dewar containing cryogenic fluids both safe and easy. PMID:22617806

  9. Blueberry Fruit Drop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Blueberry fruit drop is the name given to a new disease of blueberry that has been observed during the past few years in several blueberry fields in Oregon, Washington and British Columbia, Canada and recently in New York state. The plants flower normally, though the young leaves and flowers have ...

  10. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  11. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  12. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental Radiation Occurrences § 1002.20 Reporting of accidental radiation occurrences. (a) Manufacturers of electronic...

  13. Modelling of accidental released toxic gases for emergency responders in Austria, Kosovo and Bulgaria.

    NASA Astrophysics Data System (ADS)

    Stenzel, Sirma; Baumann-Stanzer, Kathrin; Gashi, Salih; Thaci, Bashkim; Batchvarova, Ekaterina; Spassova, Tatiana

    2010-05-01

    In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. A number of models for the prediction and simulation of hazard areas affected by accidental releases of toxic gases are available worldwide. Modelling accidental releases may be required for a variety of reasons: for analyzing different accidental toxic release scenarios ("worst-case scenarios"), for preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management (e.g. in the frame of the SEVESO directive). Depending on the demand and the particular purposes, the choice of the appropriate model is up to the authorities. The one year project was funded by the Austrian Science and research liaison Office (ASO, www.aso.zsi.at) as a part of the program: Research Cooperation and Networking between Austria, the public higher education institutions in Kosovo and South Eastern Europe. The project was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG, http://www.zamg.ac.at) in cooperation with the University of Prishtina (Kosovo, www.uni-pr.edu and the National Institute of meteorology and Hydrology (NIHM Bulgaria, www.meteo.bg). One of the main purposes of the project was to provide the both partners with basic knowledge in modelling with accidental release of toxic gases, based on the practical experience of the meteorologists from the ZAMG in the area. This knowledge can be used as scientific response to society driven current or upcoming problems especially in Kosovo. The activities involved know-how transfer on European standards and practice among the project partners, as well as joint efforts to adapt and disseminate the scientific methods and results in Kosovo. Within the project, the partners from Kosovo and Bulgaria were introduced to the atmospheric dispersion model (ALOHA - Areal Location of Hazardous atmosphere) and proceeded several model runs based on reference scenarios for chemicals of concern. ALOHA is one of the tools developed by EPA's Office of Emergency Management (OEM) and the National Oceanic and Atmospheric Administration Office of Response and Restoration (NOAA), to assist front-line chemical emergency planners and responders. In the frame of the project the partners in Kosovo and Bulgaria also undertook first steps in establishing cooperation connections with decision makers for emergency response planning, fire brigades and chemical plants. This presentation focuses on basic issues and problems in handling with accidental release of toxic gases, as well as on communication difficulties among the emergency responders, modellers and authorities in the three countries.

  14. Assessment of hazard of chemical accidental releases triggered by floods

    NASA Astrophysics Data System (ADS)

    Simonova, M.; Danihelka, P.

    2009-04-01

    Recently, the number of accidents happened, when floods trigger the releases of hazardous materials and following environment contamination. Baia Mare (Romania), Spolana Neratovice (Czech Republic) and hurricane Katrina (USA) are well known examples. The importance of this kind of phenomenon as a type of so called NATECH events is expressed among others in the Water Framework Directive 2000/60/EC, which reorganises water conservation in Europe. It requires programmes of protection measures to be drawn up not later than 2009, and in sub-article 11 (3) l b) to prevent and/or reduce the impact of accidental pollution incidents, for example as a result of floods. Effective measures demand the assessment of hazard and risk of accidental release triggered by floods and there is a need for the method which can be used for these purposes. Such a method is still missing and this is why the basic method for hazard assessment has been developed. Simple indexes-based method is composed of three segments (natural risks, technological risks and combined risk) and it has flexible, modular structure. First segment estimates the probability of flooding of installation, the second, based on the reference scenarios estimates the possibility of release of chemicals and the third classify consequences. The work on refining of parameters and method continues. Method can be used in prevention of major accidents in the framework of the Council Directive 96/82/EC on the control of major-accident hazards involving dangerous substances (Seveso II directive) and can help to complete the safety studies in classified establishments.

  15. Accidental head trauma and retinal hemorrhage.

    PubMed

    Johnson, D L; Braun, D; Friendly, D

    1993-08-01

    Retinal hemorrhage and intracranial hemorrhage in a child with little external evidence of trauma and with a poorly documented history are considered pathognomonic child abuse. The mechanism and magnitude of force required to produce the injuries are seldom witnessed or known. This study was designed to determine the incidence of retinal hemorrhage in pediatric head injuries under known accidental circumstances, in association with forces sufficient to cause skull fracture and/or intracranial hemorrhage. Of 525 consecutive hospital admissions for head injuries, 200 children filled these criteria. Thirty children were excluded because of suspected child abuse or gunshot wounds. Of the remaining 170, 140 were evaluated by an ophthalmologist for retinal hemorrhage. Two children, who were both involved in side-impact car accidents, had retinal hemorrhages in associated with severe head injury. Retinal hemorrhage occurs rarely in accidental head injury and is associated with extraordinary force. PMID:8367044

  16. A probabilistic model for accidental cargo oil outflow from product tankers in a ship-ship collision.

    PubMed

    Goerlandt, Floris; Montewka, Jakub

    2014-02-15

    In risk assessment of maritime transportation, estimation of accidental oil outflow from tankers is important for assessing environmental impacts. However, there typically is limited data concerning the specific structural design and tank arrangement of ships operating in a given area. Moreover, there is uncertainty about the accident scenarios potentially emerging from ship encounters. This paper proposes a Bayesian network (BN) model for reasoning under uncertainty for the assessment of accidental cargo oil outflow in a ship-ship collision where a product tanker is struck. The BN combines a model linking impact scenarios to damage extent with a model for estimating the tank layouts based on limited information regarding the ship. The methodology for constructing the model is presented and output for two accident scenarios is shown. The discussion elaborates on the issue of model validation, both in terms of the BN and in light of the adopted uncertainty/bias-based risk perspective. PMID:24462237

  17. Computer code to assess accidental pollutant releases

    SciTech Connect

    Pendergast, M.M.; Huang, J.C.

    1980-07-01

    A computer code was developed to calculate the cumulative frequency distributions of relative concentrations of an air pollutant following an accidental release from a stack or from a building penetration such as a vent. The calculations of relative concentration are based on the Gaussian plume equations. The meteorological data used for the calculation are in the form of joint frequency distributions of wind and atmospheric stability.

  18. Macular pucker following accidental laser burn

    SciTech Connect

    Glovinsky, Y.; Regenbogen, L.; Bartov, E.; Blumenthal, M.; Moisseieve, Y.

    1982-01-01

    A case of an accidental exposure to a high intensity Q-switched infrared laser beam is described. A paramacular burn, splinter hemorrhages on the disc margin, and vitreous hemorrhage were the initial findings. Later, a paramacular pucker developed, causing reduction in visual acuity to 6/12. Microvascular accident on the disc margin is assumed to be the cause of a paracentral scotoma located fairly far from the image area.

  19. Numerical Simulations of Drop Collisions

    NASA Technical Reports Server (NTRS)

    Nobari, M. R. H.; Tryggvason, G.

    1994-01-01

    Three-dimensional simulations of the off-axis collisions of two drops are presented. The full Navier-Stokes equations are solved by a Front-Tracking/Finite-Difference method that allows a fully deformable fluid interface and the inclusion of surface tension. The drops are accelerated towards each other by a body force that is turned off before the drops collide. Depending on whether the interface between the drops is ruptured or not, the drops either bounce or coalesce. For drops that coalesce, the impact parameter, which measures how far the drops are off the symmetry line, determines the eventual outcome of the collision. For low impact parameters, the drops coalesce permanently, but for higher impact parameters, a grazing collision, where the drops coalesce and then stretch apart again is observed. The results are in agreement with experimental observations.

  20. Bleeding disorders and non-accidental injury.

    PubMed Central

    O'Hare, A E; Eden, O B

    1984-01-01

    Fifty children with suspected non-accidental injury, most of whom had bruising, were investigated to exclude a bleeding disorder. The following investigations were undertaken in each child: full blood count; platelet count, size, and shape; prothrombin time; partial thromboplastin time including mix with normal plasma; fibrinogen; and a bleeding time. The results of these initial investigations were abnormal in eight children (16%). One child had a severe coagulopathy secondary to spontaneously acquired inhibitory activity to coagulation factors which led to spontaneous bruising and noticeable signs of injury after a minor accident. The remaining children had several features supporting a diagnosis of non-accidental injury. Two had associated bleeding disorders in the form of von Willebrand's disease and a platelet aggregation abnormality and a baby had an acquired platelet disorder secondary to salicylates, provoking severe haemorrhage from a minor injury. The remaining four children initially had an abnormal laboratory finding--a prolonged partial thromboplastin time--which resulted in lengthy discussions during subsequent legal proceedings. Evidence of a bleeding disorder is not uncommon in non-accidental injury and the two conditions are not mutually exclusive. PMID:6486863

  1. Drop tube technical tasks

    NASA Technical Reports Server (NTRS)

    Workman, G. L.

    1986-01-01

    Criteria, using fundamental thermochemical dynamics, were developed to assist a scientist using the Drop Tube Facility in designing a good experiment. The types of parameters involved in designing the experiments include the type of furnace, the type of atmosphere, and in general which materials are better behaved than others as determined by past experience in the facility. One of the major advantages of the facility lies in its ability to provide large undercoolings in the cooling curve during the drops. A beginning was to consider the effect of oxygen and other gases upon the amount of undercooling observed. The starting point of the thermochemistry was given by Ellingham and later transformed into what is known as the Richardson Chart. The effect of surface oxidations upon the nucleation phenomena can be observed in each specimen.

  2. Exploding Water Drops

    NASA Astrophysics Data System (ADS)

    Reich, Gary

    2016-01-01

    Water has the unusual property that it expands on freezing, so that ice has a specific gravity of 0.92 compared to 1.0 for liquid water. The most familiar demonstration of this property is ice cubes floating in a glass of water. A more dramatic demonstration is the ice bomb shown in Fig. 1. Here a cast iron flask is filled with water and tightly stoppered. The flask is then cooled, either by leaving it outdoors in winter or by immersing it in a cryogenic fluid, until the water freezes. As the water freezes and expands, the pressure inside the flask increases dramatically, eventually becoming sufficient to fracture the metal walls of the enclosure. A related, but much less familiar, phenomenon is the explosive fracturing of small water drops upon freezing. That water drops can fracture in this way has been known for many years, and the phenomenon has been described in detail in the atmospheric sciences literature, where it is seen as relevant to the freezing of raindrops as they fall through cold air. Carefully controlled experiments have been done documenting how the character and frequency of fracture is affected by such variables as drop size, rate of cooling, chemistry of dissolved gases, etc. Here I describe instead a simple demonstration of fracture suitable for video analysis and appropriate for study at the introductory physics level. Readers may also be interested in other characteristics of freezing and fragmenting water drops, for example, charge separation upon fracture and the appearance of spikes and bulges on the surface.

  3. MATHEMATICAL-Universe-Hypothesis(MUH) BECOME SCENARIO(MUS)!!! (NOT YET A THEORY) VIA 10-DIGITS[ 0 --> 9] SEPHIROT CREATION AUTOMATICALLY from DIGITS AVERAGED-PROBABILITY Newcomb-Benford LOG-Law; UTTER-SIMPLICITY!!!: It's a Jack-in-the-Box Universe: Accidental?/Purposeful?; EMET/TRUTH!!!

    NASA Astrophysics Data System (ADS)

    Siegel, Edward Carl-Ludwig

    2015-04-01

    Siegel(2012) 10-DIGITS[0 --> 9] AVERAGE PROBABILITY LOG-Law SCALE-INVARIANCE UTTER-SIMPLICITY: Kabbala SEPHIROT SCENARIO AUTOMATICALLY CREATES a UNIVERSE: (1) a big-bang[bosons(BEQS) created from Newcomb[Am.J.Math.4(1),39(1881;THE discovery of the QUANTUM!!!)-Poincare[Calcul des Probabilites,313(12)]-Weyl[Goett.Nach.(14);Math.Ann.77,313(16)] DIGITS AVERAGE STATISTICS LOG-Law[ = log(1 +1/d) = log([d +1]/d)] algebraic-inversion, (2)[initial (at first space-time point created) c = ∞ elongating to timelike-pencil spreading into finite-c light-cone] hidden-dark-energy (HDE)[forming at every-spacetime-point], (3) inflation[logarithm algebraic-inversion-to exponential], (4) hidden[in Siegel(87) ``COMPLEX quantum-statistics in (Nottale-Linde)FRACTAL-dimensions'' expansion around unit-circle/roots-of-unity]-dark-matter(HDM), (4)null massless bosons(E) --> Mellin-(light-speed squared)-transform/Englert-Higgs ``mechanism'' -->(timelike) massive fermions(m), (5) cosmic-microwave-background (CMB)[power-spectrum] Zipf-law HYPERBOLICITY, (6) supersymmetry(SUSY) [projective-geometry conic-sections/conics merging in R/ C projective-plane point at ∞]. UTTER-SIMPLICITY!!!

  4. Leidenfrost Drop on a Step

    NASA Astrophysics Data System (ADS)

    Lagubeau, Guillaume; Le Merrer, Marie; Clanet, Christophe; Quere, David

    2008-11-01

    When deposited on a hot plate, a water droplet evaporates quickly. However, a vapor film appears under the drop above a critical temperature, called Leidenfrost temperature, which insulates the drop from its substrate. Linke & al (2006) reported a spontaneous movement of such a drop, when deposited on a ratchet. We study here the case of a flat substrate decorated with a single micrometric step. The drop is deposited on the lower part of the plate and pushed towards the step at small constant velocity. If the kinetic energy of the drop is sufficient, it can climb up the step. In that case, depending on the substrate temperature, the drop can either be decelerated or accelerated by the step. We try to understand the dynamics of these drops, especially the regime where they accelerate. Taking advantage of this phenomenon, we could then build a multiple-step setup, making it possible for a Leidenfrost drop to climb stairs.

  5. Drop foot corrective device

    NASA Technical Reports Server (NTRS)

    Deis, B. C. (Inventor)

    1986-01-01

    A light weight, economical device to alleviate a plurality of difficulties encountered in walking by a victim suffering from a drop foot condition is discussed. A legband girdles the leg below the knee and above the calf providing an anchor point for the upper end of a ligament having its lower end attached to a toe of a shoe or a toe on the foot. The ligament is of such length that the foot is supported thereby and retained in a normal position during walking.

  6. Anaphylaxis after accidental ingestion of kiwi fruit

    PubMed Central

    Różalska, Anna; Ukleja-Sokołowska, Natalia; Żbikowska-Gotz, Magdalena; Bartuzi, Zbigniew

    2013-01-01

    Numerous cases of anaphylaxis after ingestion of kiwi fruit, after the skin tests and during oral immunotherapy were described. The article describes the case of severe anaphylactic reaction that occurred in a 55-year-old patient after accidental ingestion of kiwi. Allergy to kiwi fruit was confirmed by a native test with fresh kiwi fruit. After the test, the patient experienced generalized organ response in the form of headache, general weakness and rashes on the neck and breast, and dyspnea. The patient had significantly elevated levels of total IgE and IgE specific to kiwi fruit. PMID:24278073

  7. Accidental electrocution during autoeroticism: a shocking case.

    PubMed

    Schott, Jennifer C; Davis, Gregory J; Hunsaker, John C

    2003-03-01

    A case of atypical autoerotic death is described. An 18-year-old white man clad in two brassieres was found dead in his bedroom by his brother. Two wet green terry cloths were under the brassiere cups, connected to the house current via two metal washers and a bifid electrical cord. Literature depicting nude women was found near the victim. Autopsy revealed second-degree and third-degree burns of the mammary regions. Death was attributed to accidental self-electrocution. The authors will discuss typical and atypical forms of autoerotic death. PMID:12605007

  8. Accidental fatal inhalation of sulfuric acid fumes.

    PubMed

    Benomran, F A; Hassan, A I; Masood, S S

    2008-01-01

    A man found dead with circumstantial evidence indicating exposure to sulfuric acid vapor. He had been applying a solution of concentrated sulfuric acid to a drain pipe in an attempt to clear a blockage. External examination showed moderate corrosive damage around his mouth and nose, on his forearms and tips of fingers of his left hand. Autopsy revealed congestion of the respiratory passages, as well as severe pulmonary edema. Traces of acid and sulfate compounds were chemically detected in his upper respiratory passages. Death was attributed to accidental inhalation of fumes of strong sulfuric acid during application to blocked drainpipes. PMID:17239648

  9. Accidental Kähler moduli inflation

    SciTech Connect

    Maharana, Anshuman; Rummel, Markus; Sumitomo, Yoske

    2015-09-14

    We study a model of accidental inflation in type IIB string theory where inflation occurs near the inflection point of a small Kähler modulus. A racetrack structure helps to alleviate the known concern that string-loop corrections may spoil Kähler Moduli Inflation unless having a significant suppression via the string coupling or a special brane setup. Also, the hierarchy of gauge group ranks required for the separation between moduli stabilization and inflationary dynamics is relaxed. The relaxation becomes more significant when we use the recently proposed D-term generated racetrack model.

  10. Accidental ingestion of 35% hydrogen peroxide

    PubMed Central

    Pritchett, Sean; Green, Daniel; Rossos, Peter

    2007-01-01

    Hydrogen peroxide is a commonly used oxidizing agent with a variety of uses depending on its concentration. Ingestion of hydrogen peroxide is not an uncommon source of poisoning, and results in morbidity through three main mechanisms: direct caustic injury, oxygen gas formation and lipid peroxidation. A case of a 39-year-old man who inadvertently ingested 250 mL of unlabelled 35% hydrogen peroxide intended for natural health use is presented. Hydrogen peroxide has purported benefits ranging from HIV treatment to cancer treatment. Its use in the natural health industry represents an emerging source for accidental poisonings. PMID:17948137

  11. Controlling charge on levitating drops.

    PubMed

    Hilger, Ryan T; Westphall, Michael S; Smith, Lloyd M

    2007-08-01

    Levitation technologies are used in containerless processing of materials, as microscale manipulators and reactors, and in the study of single drops and particles. Presented here is a method for controlling the amount and polarity of charge on a levitating drop. The method uses single-axis acoustic levitation to trap and levitate a single, initially neutral drop with a diameter between 400 microm and 2 mm. This drop is then charged in a controllable manner using discrete packets of charge in the form of charged drops produced by a piezoelectric drop-on-demand dispenser equipped with a charging electrode. The magnitude of the charge on the dispensed drops can be adjusted by varying the voltage applied to the charging electrode. The polarity of the charge on the added drops can be changed allowing removal of charge from the trapped drop (by neutralization) and polarity reversal. The maximum amount of added charge is limited by repulsion of like charges between the drops in the trap. This charging scheme can aid in micromanipulation and the study of charged drops and particles using levitation. PMID:17580951

  12. Chloracne from the accidental production of tetrachlorodibenzodioxin

    PubMed Central

    May, George

    1973-01-01

    May, G. (1973).British Journal of Industrial Medicine,30, 276-283. Chloracne from the accidental production of tetrachlorodibenzodioxin. Following the accidental production of 2,3,7,8-tetrachlorodibenzodioxin (dioxin) as the result of an exothermic reaction at a chemical plant in Derbyshire, 79 cases of chloracne were recorded, many of them severe. Contrary to the usual experience they have responded very favourably to treatment and there were no cases of contact chloracne among relatives or domestic animals in the initial outbreak. However, two cases of contact chloracne were recorded three years later. Similar incidents are known to have occured in both Europe and the United States of America, almost invariably accompanied by widespread severe illness and with fatalities. Apart from one death due to an explosion which followed the exothermic reaction the more serious sequelae, which may range from depression and loss of weight to liver, kidney, and cardiac failure as well as malignant disease, have not occurred. A quick and reliable method of biological assay for the presence of dioxin in produced trichlorophenol was developed based on oral dosage to rabbits with assessment of liver function at fixed time intervals thereafter. This test has already been superseded by instantaneous gas-liquid chromatography. An entirely new plant with suitable modifications and multiple safety features has now been in satisfactory operation for three years. Images PMID:4269256

  13. Accidental ecstasy poisoning in a toddler.

    PubMed

    Melian, Abian Montesdeoca; Burillo-Putze, Guillermo; Campo, Candelaria Gonzalez; Padron, Agustin Gonzalez; Ramos, Carlos Ormazabal

    2004-08-01

    A child of 14 months accidentally swallowed a portion of an Ecstasy pill. Forty minutes after ingestion, he started a generalized convulsion. He also presented hyperthermia (38 degrees C), hypertension, tachycardia (130 bpm), ventricular extrasystoles, tachypnea (50 rpm), and mydriasis. At the hospital 5 hours later, the urine levels of amphetamine/metamphetamine were >16 mg/L. He was treated with general support measures and benzodiazepines intravenously and admitted to the pediatric intensive care unit. During the first 12 hours, he continued with hypertension, tachycardia, and long periods of trigeminy, without hemodynamic repercussion. He was discharged fully recovered. Gas chromatography/mass spectrometry analysis (8 hours after ingestion) showed a serum level of 3,4 methylenedioximethylamphetamine (MDMA) of 0.591 mg/L. The 3 cases described in the literature have shown a good evolution of Ecstasy poisoning in toddlers and infants, despite an initial critical situation. Regarding adults, the toddler intoxication seems to present symptoms sooner (20 to 30 minutes), having as an initial manifestation convulsions. However, great care must be taken on accidental ingestion of these attractive design pills. PMID:15295251

  14. Looking Under a Leidenfrost Drop

    NASA Astrophysics Data System (ADS)

    Burton, Justin; Sharpe, Aaron; van der Veen, Roeland; Franco, Andres; Nagel, Sidney

    2011-11-01

    The Leidenfrost effect can be observed when small water drops move around effortlessly without sticking on a hot pan. The transition to a levitated state, where the drops rest on an insulating layer of vapor, occurs at the Leidenfrost temperature. Experiment and theory have examined the lifetime and maximum size of Leidenfrost drops. However, the liquid-vapor interface beneath the drop has not been fully charcterized. We report experiments using laser-light interference to measure the geometry of the liquid-vapor interface. By imaging the interference fringes produced between the bottom surface of the liquid and the hot substrate, we can measure the curvature of the vapor pocket beneath the drop as well as the azimuthal undulations along the neck that sits closest to the surface. From these measurements, we can extrapolate the shape of the bottom of the drop, which fluctuates in time with a period of a few milliseconds for millimeter-sized water drops. Our measurements of the azimuthal neck radius agree with predictions: the difference between the drop and neck radii, (Rd -Rn) ~0.53 λ in the limit of large drops where λ is the capillary length of the fluid. For small drops we recover the result found in that Rn ~Rd2 / λ .

  15. Accidental Turbulent Discharge Rate Estimation from Videos

    NASA Astrophysics Data System (ADS)

    Ibarra, Eric; Shaffer, Franklin; Savaş, Ömer

    2015-11-01

    A technique to estimate the volumetric discharge rate in accidental oil releases using high speed video streams is described. The essence of the method is similar to PIV processing, however the cross correlation is carried out on the visible features of the efflux, which are usually turbulent, opaque and immiscible. The key step in the process is to perform a pixelwise time filtering on the video stream, in which the parameters are commensurate with the scales of the large eddies. The velocity field extracted from the shell of visible features is then used to construct an approximate velocity profile within the discharge. The technique has been tested on laboratory experiments using both water and oil jets at Re ~105 . The technique is accurate to 20%, which is sufficient for initial responders to deploy adequate resources for containment. The software package requires minimal user input and is intended for deployment on an ROV in the field. Supported by DOI via NETL.

  16. Accidental infant death and stroller-prams.

    PubMed

    Byard, R W; Beal, S M; Simpson, A; Carter, R F; Khong, T Y

    1996-08-01

    A three-month-old boy and an eight-month-old boy died from accidental positional asphyxia and hanging, respectively, after being placed to sleep unsupervised in stroller-prams. Both infants had moved down towards the fronts of the stroller-prams. The younger infant fell out when the footplate collapsed and he was found hanging from a metal bar on the side. The older infant had partly slipped through the front and was suspended with his head and arms within the stroller-pram and with his face pushed firmly into the mattress by a horizontal metal bar. Stroller-prams are a potentially dangerous sleeping environment unless infants are closely supervised, gaps in the front of stroller-prams closed and upright footplates stabilised. PMID:8709876

  17. Accidental Deaths Among British Columbia Indians

    PubMed Central

    Schmitt, N.; Hole, L. W.; Barclay, W. S.

    1966-01-01

    A statistical and epidemiological review of British Columbia native Indian and non-Indian mortality revealed that accidents were the leading cause of death among Indians but ranked only fourth among non-Indians. Comparison of accidental death rates by age and sex showed that, without exception, the rates among Indians were considerably higher than the corressponding rates for non-Indians. While the Indians represented some 2% of the total population of British Columbia, they accounted for over 10% of the total accident fatalities, 29% of drownings, and 21% of fatal burns. Socioeconomic, environmental and psychosocial factors and excessive drinking are considered the chief causes responsible for this rather unusual epidemiological phenomenon. This study revealed certain hazardous conditions which are specific to the Indian's present way of life. In the authors' opinion the recognition of these specific hazards is imperative for the planning of effective preventive campaigns. PMID:5902238

  18. Accidental overdose of mitoxantrone in three patients.

    PubMed

    Siegert, W; Hiddemann, W; Koppensteiner, R; Büchner, T; Essink, M; Huhn, D; Jung, M; Marosi, L; Martin, T; Minar, E

    1989-01-01

    Mitoxantrone is a new effective antineoplastic agent with activity against a wide range of tumors. Compared with the anthracycline drugs doxo- and daunorubicin, it exhibits a clearly lower toxicity and, most importantly, a reduced cardiotoxicity. The analysis of the side-effects recorded after accidental overdosage of the drug gives additional insight into its tolerability. Here we describe our observations in three patients who inadvertently received 100 mg m-2 (two pts) and 183 mg m-2 (one pt) as single slow bolus injections. The main side-effects were moderate nausea and vomiting, shaking chills, and profound but reversible neutro- and thrombocytopenia. There was no immediate cardiac toxicity. One patient with extensive previous daunomycin exposure developed congestive heart failure after 4 months. Two patients were not evaluable for late cardiac complications because of early death due to tumor progression. PMID:2559263

  19. Accidental etizolam ingestion in a child.

    PubMed

    Kato, Zenichiro; Nakamura, Mitsuhiro; Funato, Michinori; Kuwabara, Hideaki; Kondo, Naomi

    2007-07-01

    Etizolam (ETZ) is an antidepressive thienodiazepine drug that is used worldwide. The most frequent adverse effects in adults are drowsiness and muscle weakness, and this can rarely cause paradoxical excitation; however, no information exists on intoxication in children. Furthermore, evidence bearing on its safety in children is not available. We present a case of a child who accidentally took a single dose of ETZ, approximately the same as a therapeutic dose for adults, and who showed paradoxical excitation and muscle weakness. The case presented here suggests that pediatricians and emergency physicians should be aware of the possible adverse effects in children and therapeutic approaches in intoxication of ETZ and the necessity of further investigations on a specific therapeutic guideline for overdose management especially in children. PMID:17666930

  20. Rickettsial infection caused by accidental conjunctival inoculation.

    PubMed

    Brissos, Joao; de Sousa, Rita; Santos, Ana Sofia; Gouveia, Catarina

    2015-01-01

    The most common transmission route of tick-borne Rickettsia is through tick bite; nevertheless, other transmission routes should also be considered. We report a case of rickettsial infection in a 15-year-old boy caused by accidental contamination of the conjunctiva through the infected fluid of a crushed engorged tick removed from a dog. Right eye pain, conjunctival hyperaemia with mucopurulent exudate, chemosis and eyelid oedema were the first signs and symptoms. Two days later, the boy developed fever, myalgia, headache, abdominal pain and was vomiting; physical examination showed multiple cervical adenopathies but no rash. He was treated with doxycycline (200 mg/day) for 7 days with progressive resolution of clinical signs. Rickettsial infection was confirmed by immunofluorescence assay with serological seroconversion in two consecutive samples. Rickettsia conorii or Rickettsia massiliae were the possible causal agents since they are the Rickettsia spp found in the Rhipicephalus sanguineus dog tick in Portugal. PMID:25568272

  1. Radiological consequences of a postulated drop of a maximally Lloaded FFTF fuel cask

    SciTech Connect

    Scott, P.A.

    1995-09-22

    Onsite and site boundary radiological consequences were estimated for a postulated accidental drop of an Interim Storage Cask (ISC) loaded 7 assemblies at the maximum available burnup. The postulated cask drop was assumed to occur from the maximum physically attainable height during crane movement of the cask. The resulting onsite and site boundary doses of 45 mSv and 0.04 mSv are far below the corresponding 1 Sv and 250 mSv risk guidelines for highly unlikely accidents

  2. Apfel's superheated drop detector

    NASA Astrophysics Data System (ADS)

    D'Errico, Francesco

    2001-05-01

    The introduction of new approaches for radiation dosimetry is rare. A similar breakthrough occurred in 1979, when Robert Apfel invented the superheated drop detector, a miniature relative of the bubble chamber. A fundamental in high-energy particle physics, the bubble chamber utilizes a liquid briefly brought to a transient, radiation-sensitive superheated state by reducing its pressure. Mass boiling of the liquid is prevented by cyclic pressurization, drastically limiting the detection efficiency. In Apfel's detector, the liquid is kept in a steady superheated state by fractionating it into droplets and dispersing them in an immiscible host fluid, a perfectly smooth and clean container. The approach extends the lifetime of the metastable droplets to the point that practical application in radiation dosimetry is possible. Bubble formation is measured from the volume of vapor or by detecting individual vaporizations acoustically. Various halocarbons are employed and this permits a wide range of applications. Moderately superheated halocarbons are used for neutron measurements, since they are only nucleated by energetic neutron recoil particles. Highly superheated halocarbons nucleate with much smaller energy deposition and are used to detect photons and electrons. This paper reviews the radiation physics of superheated emulsions and their manifold applications.

  3. The dropped big toe.

    PubMed

    Satku, K; Wee, J T; Kumar, V P; Ong, B; Pho, R W

    1992-03-01

    Surgical procedures for exposure of the upper third of the fibula have been known to cause weakness of the long extensor of the big toe post-operatively. The authors present three representative cases of surgically induced dropped big toe. From cadaveric dissection, an anatomic basis was found for this phenomenon. The tibialis anterior and extensor digitorum longus muscles have their origin at the proximal end of the leg and receive their first motor innervation from a branch that arises from the common peroneal or deep peroneal nerve at about the level of the neck of the fibula. However, the extensor hallucis longus muscle originates in the middle one-third of the leg and the nerves innervating this muscle run a long course in close proximity to the fibula for up to ten centimeters from a level below the neck of the fibula before entering the muscle. Surgical intervention in the proximal one-third of the fibula just distal to the origin of the first motor branch to the tibialis anterior and extensor digitorum longus muscles carries a risk of injury to the nerves innervating the extensor hallucis longus. PMID:1519891

  4. Experiences of Causing an Accidental Death: An Interpretative Phenomenological Analysis

    ERIC Educational Resources Information Center

    Rassool, Sara B.; Nel, Pieter W.

    2012-01-01

    Accidentally killing or feeling responsible for another person's death constitutes an event that is different from many typical traumatic stressors in that the responsibility for causing the trauma is located in the person themselves, rather than another person or persons. Research exploring the perspective of those who have accidentally caused a

  5. Course Management Systems for Learning: Beyond Accidental Pedagogy

    ERIC Educational Resources Information Center

    McGee, Patricia; Carmean, Colleen; Jafari, Ali

    2005-01-01

    "Course Management Systems for Learning: Beyond Accidental Pedagogy" is a comprehensive overview of standards, practices and possibilities of course management systems in higher education. "Course Management Systems for Learning: Beyond Accidental Pedagogy" focuses on what the current knowledge is (in best practices, research, standards and…

  6. 49 CFR 192.195 - Protection against accidental overpressuring.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Protection against accidental overpressuring. 192.195 Section 192.195 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE... Pipeline Components § 192.195 Protection against accidental overpressuring. (a) General...

  7. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... radiation occurrence occurred; (3) The manufacturer, type, and model number of the electronic product or... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental...

  8. 21 CFR 1002.20 - Reporting of accidental radiation occurrences.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... radiation occurrence occurred; (3) The manufacturer, type, and model number of the electronic product or... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Reporting of accidental radiation occurrences... SERVICES (CONTINUED) RADIOLOGICAL HEALTH RECORDS AND REPORTS Manufacturers' Reports on Accidental...

  9. Experiences of Causing an Accidental Death: An Interpretative Phenomenological Analysis

    ERIC Educational Resources Information Center

    Rassool, Sara B.; Nel, Pieter W.

    2012-01-01

    Accidentally killing or feeling responsible for another person's death constitutes an event that is different from many typical traumatic stressors in that the responsibility for causing the trauma is located in the person themselves, rather than another person or persons. Research exploring the perspective of those who have accidentally caused a…

  10. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  11. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  12. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  13. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Maintenance § 192.751 Prevention of accidental ignition. Each operator shall take steps to minimize the danger of accidental ignition of gas in any structure or area where the presence of gas constitutes a hazard of fire or explosion,...

  14. Gas Pressure-Drop Experiment

    ERIC Educational Resources Information Center

    Luyben, William L.; Tuzla, Kemal

    2010-01-01

    Most chemical engineering undergraduate laboratories have fluid mechanics experiments in which pressure drops through pipes are measured over a range of Reynolds numbers. The standard fluid is liquid water, which is essentially incompressible. Since density is constant, pressure drop does not depend on the pressure in the pipe. In addition, flow

  15. Gas Pressure-Drop Experiment

    ERIC Educational Resources Information Center

    Luyben, William L.; Tuzla, Kemal

    2010-01-01

    Most chemical engineering undergraduate laboratories have fluid mechanics experiments in which pressure drops through pipes are measured over a range of Reynolds numbers. The standard fluid is liquid water, which is essentially incompressible. Since density is constant, pressure drop does not depend on the pressure in the pipe. In addition, flow…

  16. Hanging drop crystal growth apparatus

    NASA Technical Reports Server (NTRS)

    Naumann, Robert J. (Inventor); Witherow, William K. (Inventor); Carter, Daniel C. (Inventor); Bugg, Charles E. (Inventor); Suddath, Fred L. (Inventor)

    1990-01-01

    This invention relates generally to control systems for controlling crystal growth, and more particularly to such a system which uses a beam of light refracted by the fluid in which crystals are growing to detect concentration of solutes in the liquid. In a hanging drop apparatus, a laser beam is directed onto drop which refracts the laser light into primary and secondary bows, respectively, which in turn fall upon linear diode detector arrays. As concentration of solutes in drop increases due to solvent removal, these bows move farther apart on the arrays, with the relative separation being detected by arrays and used by a computer to adjust solvent vapor transport from the drop. A forward scattering detector is used to detect crystal nucleation in drop, and a humidity detector is used, in one embodiment, to detect relative humidity in the enclosure wherein drop is suspended. The novelty of this invention lies in utilizing angular variance of light refracted from drop to infer, by a computer algorithm, concentration of solutes therein. Additional novelty is believed to lie in using a forward scattering detector to detect nucleating crystallites in drop.

  17. Binary drop coalescence in liquids

    NASA Astrophysics Data System (ADS)

    Kim, Jungyong

    Experiments on binary drop collisions within an index-matched liquid were conducted for Weber numbers (We) of 1-50 and collision angles of 15-80° below the horizontal. Drop pairs of water/glycerin mixture were injected into silicone oil and, due to gravitational effects, traveled on downward trajectories before colliding. A dual-field high-speed PIV measurement system was employed to quantify drop trajectories and overall collision conditions while simultaneously examining detailed velocity fields near the collision interface. In the We range examined, for equal size drops, both rebounding and coalescing behavior occurred. The drops coalesced for We > 10 and rebounded for We < 10, and this boundary was found to be insensitive to collision angle. Coalescence was found to result from a combination of vortical flow within drops and strong drop deformation characteristic of higher We. Flow through the centers of opposing ring vortices, strengthened by drop deformation, enhanced drainage of the thin film in the impact region, leading to film rupture and coalescence. The collision angle affected the eventual location of film rupture, with the rupture location moving higher in the thin film region as the collision angle increased. The film rupture location correlated closely with the location of maximum downward velocity in the thin film. The time between collision and rupture increases with We until We = 30. For We > 30, the time decreases as We increases. Unequal size drop collisions with drop size ratios (Ds/D L) of 0.7 and 0.5 were also examined. Coalescence occurs above We* = 11 similar to equal size drops. As drop size ratio decreases, the intervening film deforms more. If the velocity ratio uL/u s < 1, the deformed interface becomes flat before coalescence. The rupture location varies due to the asymmetry of the drops. As collision offset increases (B > 0), the film rupture time is shortened and mixing of the fluid from both drops is enhanced after coalescence. The presence of tracer particles in the intervening film does not affect the minimum Weber number for coalescence, but the film ruptures earlier compared with cases lacking tracer particles.

  18. Pool impacts of Leidenfrost drop

    NASA Astrophysics Data System (ADS)

    Darbois Texier, Baptiste; Maquet, Laurent; Dorbolo, Stephane; Dehandschoewercker, Eline; Pan, Zhao; Truscott, Tadd

    2015-11-01

    This work concerns the impact of a droplet made of a volatile liquid (typically HFE) on a pool of an other liquid (typically silicone oil) which temperature is above the boiling point of the drop. Depending on the properties of the two liquids and the impacting conditions, four different regimes are observed. For low impacting speeds, the droplet bounces on the surface of the bath and finally levitates above it in a Leidenfrost state. Such a regime occurs as soon as the pool temperature exceeds the boiling point of the drop. This observation means that there is no threshold in temperature for a Leidenfrost effect on a liquid surface contrary to the case of a solid substrate. For intermediate impacting velocities, the pinch-off of the surface of the pool entraps the drop in the liquid bulk. The entrapped drop is separated from the pool by a layer of its own vapour in a similar way of antibulles. For increasing impacting speeds, the vapour layer between the drop and the pool does not hold during the pinch-off event. The contact of the drop with the hot liquid provokes a sudden and intense evaporation. At very large impacting speeds, the drop rapidely contacts the pool, spreads and finally induces a hemi-spherical cavity. In the end, these four different regimes are summarized in a Froud-Weber diagram which boundaries are discussed.

  19. Electrokinetics of isolated electrified drops.

    PubMed

    Pillai, Rohit; Berry, Joseph D; Harvie, Dalton J E; Davidson, Malcolm R

    2016-04-14

    Using a recently developed multiphase electrokinetic model, we simulate the transient electrohydrodynamic response of a liquid drop containing ions, to both small and large values of electric field. The temporal evolution is found to be governed primarily by two dimensionless groups: (i) Ohnesorge number (Oh), a ratio of viscous to inertio-capillary effects, and (ii) inverse dimensionless Debye length (κ), a measure of the diffuse regions of charge that develop in the drop. The effects of dielectric polarization dominate at low Oh, while effects of separated charge gain importance with increase in Oh. For small values of electric field, the deformation behaviour of a drop is shown to be accurately described by a simple analytical expression. At large electric fields, the drops are unstable and eject progeny drops. Depending on Oh and κ this occurs via dripping or jetting; the regime transitions are shown by a Oh-κ phase map. In contrast to previous studies, we find universal scaling relations to predict size and charge of progeny drops. Our simulations suggest charge transport plays a significant role in drop dynamics for 0.1 ≤ Oh ≤ 10, a parameter range of interest in microscale flows. PMID:26954299

  20. Extension of drop experiments with the MIKROBA balloon drop facility

    NASA Astrophysics Data System (ADS)

    Sommer, K.; Kretzschmar, K.; Dorn, C.

    1992-12-01

    The German balloon drop facility MIKROBA extends the worldwide available drop experiment opportunities to the presently highest usable experimentation time span of 55 s at microgravity conditions better than 0.001 g. The microgravity period is started with the typical quasi-deal step function from 1 to 0 g. MIKROBA allows flexible experiment design, short access time, and easy hands-on payload integration. The transport to the operational height is realized by soft energies and technologies compatible with the earth's environment. Balloon campaigns are not restricted to a certain test range, i.e., several suitable sites are available all over the world. MIKROBA combines negligible mechanical loads at the mission start, typical of all drop facilities, with extremely low drop deceleration loads (less than g), due to the implemented three-stage parachute and airbag recovery subsystem.

  1. Quick management of accidental tritium exposure cases.

    PubMed

    Singh, Vishwanath P; Badiger, N M; Managanvi, S S; Bhat, H R

    2012-07-01

    Removal half-life (RHL) of tritium is one of the best means for optimising medical treatment, reduction of committed effective dose (CED) and quick/easy handling of a large group of workers for medical treatment reference. The removal of tritium from the body depends on age, temperature, relative humidity and daily rainfall; so tritium removal rate, its follow-up and proper data analysis and recording are the best techniques for management of accidental acute tritium exposed cases. The decision of referring for medical treatment or medical intervention (MI) would be based on workers' tritium RHL history taken from their bodies at the facilities. The workers with tritium intake up to 1 ALI shall not be considered for medical treatment as it is a derived limit of annual total effective dose. The short-term MI may be considered for tritium intake of 1-10 ALI; however, if the results show intake ≥100 ALI, extended strong medical/therapeutic intervention may be recommended based on the severity of exposure for maximum CED reduction requirements and annual total effective dose limit. The methodology is very useful for pressurized heavy water reactors (PHWRs) which are mainly operated by Canada and India and future fusion reactor technologies. Proper management will optimise the cases for medical treatment and enhance public acceptance of nuclear fission and fusion reactor technologies. PMID:22349318

  2. Accidental awareness during anesthesia in children.

    PubMed

    Sury, Michael R J

    2016-05-01

    This educational review explores the current understanding of accidental awareness during general anesthesia (AAGA) in children. Estimates of incidence in children vary between 1 in 135 (determined by direct questioning) and 1 in 51 500 (determined from spontaneous reporting). The lessons from the 5th National Audit Project of the Royal College of Anaesthetists and the Association of Anaesthetists of Great Britain and Ireland show that the characteristics of spontaneous reports of AAGA are extremely variable and relate to the type of procedure and anesthetic technique rather than age group: approximately 50% of experiences were distressing; most lasted less than 5 min; neuromuscular blockade (NMB) combined with pain caused the most distress; most cases (approximately 70%) occur at induction or emergence. The value of depth of anesthesia monitoring in preventing AAGA is uncertain but is probably useful in patients having total intravenous anesthesia and NMB. Reports of AAGA by children should be received sympathetically and a generic protocol for managing distressed patients is presented. PMID:27059416

  3. [Accidental bilateral asymmetric ruby laser maculopathy].

    PubMed

    Lang, G K; Lang, G; Naumann, G O

    1985-05-01

    A 19-year-old man sustained a bilateral coagulation of the macula caused accidentally by a ruby laser rangefinder mounted on a tank. Five days later vision was OD 0.7, OS 0.05; there was a distinct disk of coagulation of the retinal pigment epithelium with clumping of melanin granula, more in the left eye than in the right, and subretinal hemorrhage on the left. Visual improvement corresponded to the asymmetric morphologic findings: Within two months visual acuity in the right eye recovered to 1.0. In the left eye there was a temporary increase to 0.3, then permanent deterioration of vision to 0.05 OS. The macula of the left eye showed massive lipofuscein aggregation in the subretinal space. Fluorescein angiography after two months showed some hyperfluorescence, more in the left than in the right eye, but no fluorescein extravasation. The vision in the left eye is still 0.05 one year after the accident. PMID:4021426

  4. [Psychological aspects of accidental poisoning in children].

    PubMed

    Trabach-Valadier, C; Floret, D

    1987-01-01

    The following points stand out from a semi-open questionnaire which was sent to the parents of 28 children hospitalized for accidental intoxication. Intoxications often occur in children who are hyperactive, curious, rebellious and have strong affective needs. Parents find it very difficult to set bans and limitations to their children, whose behaviour seems to be actively calling out for such restrictions. These children frequently put themselves in a situation of self-aggression, which shows the parents' inability to teach them to develop a vital self protective attitude from life's daily experience. Most often, the child is aware of transgressing a ban and in a few cases, intoxication seems to be a deliberate act on his part. It generally occurs when stress has been building up in the family, thus threatening the balance of the family. If it happens in a family where relationships are already deeply disturbed, it must be considered as a signal of alarm. It is then necessary to suggest that the family should undergo a psychotherapeutic course to help them to put an end to the deadly process in which they are involved. PMID:3448592

  5. Drop propulsion in tapered tubes

    NASA Astrophysics Data System (ADS)

    Renvoisé, P.; Bush, J. W. M.; Prakash, M.; Quéré, D.

    2009-06-01

    We present the results of a combined experimental and theoretical investigation of the motion of wetting droplets in tapered capillary tubes. We demonstrate that drops may move spontaneously towards the tapered end owing to the Laplace pressure gradient established along their length. The influence of gravity on this spontaneous motion is examined by studying drop motion along a tilted tube with its tapered end pointing upwards. Provided the tube taper varies, an equilibrium height may be achieved in which the capillary force is balanced by the drop's weight. We deduce the family of tube shapes that support a stable equilibrium.

  6. Dispersion modeling of accidental releases of toxic gases - Sensitivity study and optimization of the meteorological input

    NASA Astrophysics Data System (ADS)

    Baumann-Stanzer, K.; Stenzel, S.

    2009-04-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. Uncertainties in the meteorological input together with incorrect estimates of the source play a critical role for the model results. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program at the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. This presentation gives a short introduction to the project and presents the results of task 1 (meteorological input). The results of task 2 are presented by Stenzel and Baumann-Stanzer in this session. For the aim of this project, the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) was used. INCA (Integrated Nowcasting through Comprehensive Analysis) data were calculated with 1 km horizontal resolution and based on the weather forecast model ALADIN. The meteorological field's analysis with INCA include: Temperature, Humidity, Wind, Precipitation and Cloudiness. In the frame of the project INCA data were compared with measurements conducted at traffic-near sites. INCA analysis and very short term forecast fields (up to 6 hours) are found to be an advanced possibility to provide on-line meteorological input for the model package used by the fire brigade. Nevertheless a high degree of caution in the interpretation of the model results is required - especially in the case of very slow wind speeds, very stable atmospheric condition, and flow deflection by buildings in the urban area or by complex topography.

  7. Evidence-Based Management Of Accidental Hypothermia In The Emergency Department.

    PubMed

    Rischall, Megan L; Rowland-Fisher, Andrea

    2016-01-01

    Accidental hypothermia is defined as an unintentional drop in core body temperature below 35C. It can present in any climate and in any season, as it is not always a result of environmental exposure; underlying illnesses or coexisting pathology can play important roles. Although there is some variability in clinical presentation, hypothermia produces a predictable pattern of physiologic responses and clinical manifestations, and effective treatment has yielded many impressive survival case reports. Treatment strategies focus on prevention of further heat loss, volume resuscitation, implementation of appropriate rewarming techniques, and management of cardiac dysrhythmia. Rewarming may be passive or active and/or internal or external, depending on severity and available resources. This issue focuses on methods of effective rewarming and prevention of further morbidity and mortality. PMID:26655247

  8. Accidental transection of flexometallic endotracheal tube during partial maxillectomy

    PubMed Central

    Ladi, Sushma D; Aphale, Shubhada

    2011-01-01

    We report a rare case of an 18-year-old female patient in whom accidental sectioning of flexometallic endotracheal tube occurred during partial maxillectomy for mass lesion under general anaesthesia. She was managed successfully by tracheostomy. PMID:21808404

  9. [Retinal haemorrhages in non-accidental head injury in childhood].

    PubMed

    Oberacher-Velten, I M; Helbig, H

    2014-09-01

    Retinal haemorrhages are one of the three cardinal manifestations of the "shaken baby syndrome" or "non-accidental head injury" in childhood. The role of an ophthalmologist in suspected non-accidental head injury has not only medical but also legal aspects and has been discussed controversially in the literature. The differential diagnosis and the specificity of retinal haemorrhages in childhood for an abusive head trauma will be pointed out in this paper. PMID:25181505

  10. Infrasonic signals from an accidental chemical explosion

    SciTech Connect

    Mutschlecner, J.P.; Whitaker, R.W.

    1996-12-31

    A series of large accidental explosions occurred at a chemical plant in Henderson, Nevada on May 4, 1988. The explosions were produced by the ignition of stores of ammonium perchlorate produced for solid rocket fuel at the Pacific Engineering and Production Co. This material, prior to the incident, had been believed to be non- explosive. The blasts destroyed the plant and caused one death. There was a series of explosions over a period of time with two major explosions which we will identify as A at 18:53:34 (all times herein will be given in C.U.T.) and B at 18:57:35. Signals from events A and B as well as smaller events were detected by the infrasound arrays operated by the Los Alamos National Laboratory at St. George, Utah (distance 159 km) and at Los Alamos, N.M. (distance 774 km). The Henderson explosions present an interesting and challenging set of infrasound observations. The case may be unique in providing two very large sources separated in time by only four minutes. To fully understand the propagation details will require further analysis and probably a modeling effort. The understanding of the St. George signals in the context of Lamb waves would be valuable for a better understanding of this mode of propagation. The improved understanding of long range infrasonic propagation is now especially important in the context of the Comprehensive Test Ban Treaty (CTBT). A portion of the plan for CTBT monitoring includes a global distribution of sixty infrasound arrays to provide for the monitoring of signals in as uniform a way as possible. It is expected that under this global network many signals and interpretation questions of the type described here will be encountered. Investigations of propagation over the ranges of hundreds to thousands of kilometers will be highly desired.

  11. Electrostatic Liquid-Drop-Levitation System

    NASA Technical Reports Server (NTRS)

    Rhim, Won Kyu; Chung, San Kun; Hyson, Michael T.; Elleman, Daniel D.

    1988-01-01

    Electrostatic levitator has levitated drops of liquid up to 4 mm in diameter while maintaining spherical drop shapes. Stable levitation of spherical drops valuable in experiments involving super-cooling, solidification, and crystal growth.

  12. Effect of Temperature Dropping During Reheat Treatments on GTD-111 Microstructure

    NASA Astrophysics Data System (ADS)

    Wongnawapreechachai, Piyapat; Hormkrajai, Weerasak; Lothongkum, Gobboon; Wangyao, Panyawat

    2012-04-01

    The general standard reheat treatment condition to refurbishment long-term serviced turbine blades, which are made of cast nickel based superalloy, GTD-111, is usually following by solution treatment at 1438 K, 1458 K and 1478 K for 10.8 to 14.4 ks, combination with primary aging at 1328 K for 3.6 ks, and secondary aging at 1118 K for 86.4 ks. However, in practical reheat treatment process, the change of temperature during any heat treating could occur accidentally any time. To simulate this effect, the droppings of temperatures during solution treatment were chosen and carried out to temperature level of 1118 K then heating again to the solution temperature levels. The temperature droppings (according to various programs) were performed during solution treatment. From the results, it was found that effect of temperature dropping during solution treatment greatly influenced the final rejuvenated microstructures.

  13. Drops that pull themselves up

    NASA Astrophysics Data System (ADS)

    Tadmor, Rafael

    2014-10-01

    We relate different existing literature experimental findings of drop retraction in evaporating or in coffee ring systems as a unique physical phenomenon that is not related to evaporation, but rather to the presence of surfactant molecules in the drops. The retraction is induced by fluctuations of the drop's triple line that result in a net leakage of the surfactant molecules onto the solid-air interface right across the triple line. This net leakage can be induced by either nucleation and growth of a surface defect at the triple line or random triple line fluctuations analogous to spinodal process. Using this understanding, we can set a lower limit to the value of the, otherwise un-measurable, solid-vapor interfacial energy.

  14. Drop fragmentation by laser-induced cavitation bubbles

    NASA Astrophysics Data System (ADS)

    Gonzalez-A, S. Roberto; Kerssens, Pjotr; Ohl, Claus-Dieter

    2015-11-01

    The fragmentation of water droplets by a short laser pulse has received significant attention since the 70's. The fundamental understanding of droplet vaporization/fragmentation is of interest in laser beam propagation in the atmosphere, in situ analysis of combustion products -a great concern due to its ecological implications- and more recently driven by a better understanding of the drop shaping by a laser pulse which is of interest in the development of extreme ultraviolet (EUV) machines. In this presentation we discuss about the incipient events that lead to the fragmentation of a drop produced by a cavitation bubble. When the bubble expands, it stretches the drop into a thin liquid film; this liquid film is eventually ruptured and a shockwave and small droplets are ejected as fast as 4 times the speed of sound in air. Interestingly, we also observe bubbles on the surface of the stretched film. Numerical simulations of a shock wave propagating inside a droplet show that cavitation bubbles appear when counter propagating shock waves that rebound from the walls of the drop meet. We also show different fragmentation scenarios recorded with high-speed video, one of them being a jelly fish like liquid film that eventually fragments into smaller drops.

  15. Cost of accidental carbon monoxide poisoning: A preventable expense

    PubMed Central

    Hampson, Neil B.

    2015-01-01

    Carbon monoxide (CO) poisoning is common in the United States, accounting for hundreds of deaths and thousands of emergency department visits annually. It is believed that most accidental CO poisoning is preventable through public education, warning labels on consumer products, and uniform use of residential CO alarms. However, cost effectiveness of these prevention strategies has not been demonstrated in the United States to date. It was the objective of this study to estimate societal cost of accidental CO poisoning and evaluate the cost-effectiveness of universal installation of residential CO alarms. Published studies and data from the English language literature were used in to estimate direct hospital costs and lost earnings resulting from accidental CO poisoning. The study was performed in the US in 2015. Approximately 6600 individuals are estimated to sustain long-term cognitive sequela annually, with total loss in earnings of approximately $925 million, 334 individuals die from accidental, non-fire related CO poisoning with an average loss of 26 years of productivity accounting for $355 million, and 2800 are hospitalized with acute medical care costs of $33 million. Available data indicate that accidental CO poisoning in the US conservatively costs society over $1.3 billion, resulting from direct hospital costs and lost earnings. Further, it demonstrates a positive cost-benefit ratio for the uniform use of residential CO alarms. PMID:26844181

  16. Cost of accidental carbon monoxide poisoning: A preventable expense.

    PubMed

    Hampson, Neil B

    2016-06-01

    Carbon monoxide (CO) poisoning is common in the United States, accounting for hundreds of deaths and thousands of emergency department visits annually. It is believed that most accidental CO poisoning is preventable through public education, warning labels on consumer products, and uniform use of residential CO alarms. However, cost effectiveness of these prevention strategies has not been demonstrated in the United States to date. It was the objective of this study to estimate societal cost of accidental CO poisoning and evaluate the cost-effectiveness of universal installation of residential CO alarms. Published studies and data from the English language literature were used in to estimate direct hospital costs and lost earnings resulting from accidental CO poisoning. The study was performed in the US in 2015. Approximately 6600 individuals are estimated to sustain long-term cognitive sequela annually, with total loss in earnings of approximately $925 million, 334 individuals die from accidental, non-fire related CO poisoning with an average loss of 26 years of productivity accounting for $355 million, and 2800 are hospitalized with acute medical care costs of $33 million. Available data indicate that accidental CO poisoning in the US conservatively costs society over $1.3 billion, resulting from direct hospital costs and lost earnings. Further, it demonstrates a positive cost-benefit ratio for the uniform use of residential CO alarms. PMID:26844181

  17. Reducing the loss of vaccines from accidental freezing in the cold chain: The experience of continuous temperature monitoring in Tunisia

    PubMed Central

    Lloyd, John; Lydon, Patrick; Ouhichi, Ramzi; Zaffran, Michel

    2015-01-01

    Accidental freezing of vaccines is a growing threat and a real risk for national immunization programs when the potency of many vaccines can be compromised if these are exposed to sub-zero temperatures in the cold chain. In Tunisia, this issue is compounded by using sub-standard domestic cold chain equipment instead of equipping the program with medical refrigerators designed specifically for storing vaccines and temperature sensitive pharmaceuticals. Against this backdrop, this paper presents the findings of a demonstration project conducted in Tunisia in 2012 that tested the impact of introducing several freeze prevention solutions to mitigate the risk of accidental freezing of vaccines. The main finding is that, despite the continued use of underperforming domestic refrigerators, continuous temperature monitoring using new technologies combined with other technological interventions significantly reduced the prevalence of accidental exposure to freezing temperatures. These improvements were noticed for cold chain storage at regional, district and health center levels, and during the transport legs that were part of the demonstration conducted in the regions of Kasserine in the South-Eastern part of Tunisia. Subsequent to introducing these freeze prevention solutions, the incidence of freeze alarms was reduced and the percent of time the temperatures dropped below the 2C recommended threshold. The incidence of freeze alarms at health center level was reduced by 40%. Lastly, the solutions implemented reduced risk of freezing during transport from 13.8% to 1.7%. Although the solution implemented is not optimal in the longer term because domestic refrigerators are used extensively in district stores and health centers, the risk of accidental freezing is significantly reduced by introducing the practice of continuous temperature monitoring as a standard. The management of the cold chain equipment was strengthened as a result which helps protect the potency of vaccines to the areas of most difficult access. PMID:25444810

  18. Analysis for Eccentric Multi Canister Overpack (MCO) Drops at the Canister Storage Building (CSB) (CSB-S-0073)

    SciTech Connect

    TU, K.C.

    1999-10-08

    Multi-Canister Overpacks (MCOs) containing spent nuclear fuel (SNF) will be routinely handled at the Canister Storage Building (CSB) during fuel movement operations in the SNF Project. This analysis was performed to investigate the potential for damage from an eccentric accidental drop onto the standard storage tube, overpack tube, service station, or sample/weld station. Appendix D was added to the FDNW document to include the peer Review Comment Record & transmittal record.

  19. 49 CFR 178.1045 - Drop test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Drop test. 178.1045 Section 178.1045... Containers § 178.1045 Drop test. (a) General. The drop test must be conducted for the qualification of all... subpart. (b) Special preparation for the drop test. Flexible Bulk Containers must be filled to...

  20. 49 CFR 178.810 - Drop test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Drop test. 178.810 Section 178.810 Transportation... Drop test. (a) General. The drop test must be conducted for the qualification of all IBC design types... the drop test. (1) Metal, rigid plastic, and composite IBCs intended to contain solids must be...

  1. 49 CFR 178.603 - Drop test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Drop test. 178.603 Section 178.603 Transportation... Packagings and Packages § 178.603 Drop test. (a) General. The drop test must be conducted for the... than flat drops, the center of gravity of the test packaging must be vertically over the point...

  2. Drops spreading on flexible fibers

    NASA Astrophysics Data System (ADS)

    Somszor, Katarzyna; Boulogne, François; Sauret, Alban; Dressaire, Emilie; Stone, Howard

    2015-11-01

    Fibrous media are encountered in many engineered systems such as textile, paper and insulating materials. In most of these materials, fibers are randomly oriented and form a complex network in which drops of wetting liquid tend to accumulate at the nodes of the network. Here we investigate the role of the fiber flexibility on the spreading of a small volume of liquid on a pair of crossed flexible fibers. A drop of silicone oil is dispensed at the point of contact of the fibers and we characterize the liquid morphologies as we vary the volume of liquid, the angle between the fibers, and the length and bending modulus of the fibers. Drop morphologies previously reported for rigid fibers, i.e. a drop, a column and a mixed morphology, are also observed on flexible fibers with modified domains of existence. Moreover, at small inclination angles of the fibers, a new behavior is observed: the fibers bend and collapse. Depending on the volume, the liquid can adopt a column or a mixed morphology on the collapsed fibers. We rationalize our observations with a model based on energetic considerations. Our study suggests that the fiber flexibility adds a rich variety of behaviors that can be crucial for industrial applications.

  3. Getting the Drop on Sediment

    ERIC Educational Resources Information Center

    Galindez, Peter

    1977-01-01

    In this exercise, students examine Aristotle's weight hypothesis by testing variously shaped marble chips. These chips are weighed and dropped down a water tube. Average fall times and weights are recorded and graphed. Students are asked to apply this information to rock and soil deposition by streams. (MA)

  4. Grade Dropping: An Empirical Analysis

    ERIC Educational Resources Information Center

    Sewell, Ellen

    2004-01-01

    It is a popular practice among college professors to drop the lowest component grade in computing the course grade. A benefit of this practice is the elimination of the need to evaluate excuses or administer make-up exams. The author uses data from a controlled experiment to examine the impact of such a policy on student behavior and course…

  5. How to Use Nose Drops

    MedlinePlus

    ... not chipped or cracked. Avoid touching the dropper tip against your nose or anything else--the dropper must be kept clean. Tilt your head as far back as possible, or lie down on your back on a flat surface (such as a bed) and hang your head over the edge. Place the correct number of drops into your ...

  6. Evaporation of multicomponent drop arrays

    SciTech Connect

    Annamalai, K.; Ryan, W.; Chandra, S. )

    1993-08-01

    The present paper deals with the evaporation of multicomponent fuel droplets in an array using the recently developed point source method (PSM). First, the quasisteady (QS) evaporation of an isolated, multicomponent droplet is briefly analyzed. The resultant governing equations, along with Raoult's law and the Cox-Antoine relation, constitute the set of equations needed to arrive at the solutions for: (1) the droplet surface temperature, (2) the evaporation rate of each species, and (3) the vapor mass fraction of each species at the droplet surface. The PSM, which treats the droplet as a point mass source and heat sink, is then adopted to obtain an analytic expression for the evaporation rate of a multicomponent droplet in an array of liquid droplets. Defining the correction factor ([eta]) as a ratio of the evaporation of a drop in an array to the evaporation rate of a similar isolated multicomponent drop, an expression for the correction factor is obtained. The results of the point source method (PSM) are then compared with those obtained elsewhere for a three-drop array that uses the method of images (MOI). Excellent agreement is obtained. The treatment is then extended to a binary drop array to study the effect of interdrop spacing on vaporization. 20 refs., 11 figs., 4 tabs.

  7. Impact of a viscous drop

    NASA Astrophysics Data System (ADS)

    Zhang, Wendy W.; Schroll, Robert D.; Josserand, Christophe; Zaleski, Stephane

    2009-03-01

    Recent experiments [1] reveal that reducing the ambient air pressure entirely suppresses the splash generated by the impact of an oil drop at several m/s onto a dry smooth wall. Motivated by these observations, we simulate two types of drop impact: impact onto a smooth, dry solid wall and head-on collision of two identical liquid drops. In both cases we make the additional simplification that impact simply arrests the downward fall and redirects the liquid radially outwards in a thin, expanding sheet. It does not break the drop surface. Since experiments suggest that splash is created by airflow deforming the thin sheet, we focus on the time-evolution of the thin liquid sheet but restrict ourselves to the simpler situation of negligible airflow effects. In this regime, we find that the ejected sheet is always characterized by two different lengthscales. Surface tension controls the rim size. The thickness over the rest of the sheet is controlled by a different mechanism. Impact onto a solid surface creates a pancake whose thickness is controlled by viscous dissipation. Head-on collision creates a sheet that thins continuously with distance from the collision center. Its thickness is controlled by the kinematics of impact.[0pt][1] Stevens, Keim, Zhang & Nagel, FC03 APS DFD meeting (2007)

  8. Egg Drop: An Invention Workshop

    ERIC Educational Resources Information Center

    McCormack, Alan J.

    1973-01-01

    Describes an activity designed to stimulate elementary and junior high students to become actively engaged in thinking creatively rather than only analytically, convergently, or repetitively. The activity requires students to devise means of dropping an egg from a height without it breaking. (JR)

  9. Dynamic evaluation of environmental impact due to tritium accidental release from the fusion reactor.

    PubMed

    Nie, Baojie; Ni, Muyi; Jiang, Jieqiong; Wu, Yican

    2015-10-01

    As one of the key safety issues of fusion reactors, tritium environmental impact of fusion accidents has attracted great attention. In this work, the dynamic tritium concentrations in the air and human body were evaluated on the time scale based on accidental release scenarios under the extreme environmental conditions. The radiation dose through various exposure pathways was assessed to find out the potential relationships among them. Based on this work, the limits of HT and HTO release amount for arbitrary accidents were proposed for the fusion reactor according to dose limit of ITER. The dynamic results aim to give practical guidance for establishment of fusion emergency standard and design of fusion tritium system. PMID:26164282

  10. Game theory of pre-emptive vaccination before bioterrorism or accidental release of smallpox.

    PubMed

    Molina, Chai; Earn, David J D

    2015-06-01

    Smallpox was eradicated in the 1970s, but new outbreaks could be seeded by bioterrorism or accidental release. Substantial vaccine-induced morbidity and mortality make pre-emptive mass vaccination controversial, and if vaccination is voluntary, then there is a conflict between self- and group interests. This conflict can be framed as a tragedy of the commons, in which herd immunity plays the role of the commons, and free-riding (i.e. not vaccinating pre-emptively) is analogous to exploiting the commons. This game has been analysed previously for a particular post-outbreak vaccination scenario. We consider several post-outbreak vaccination scenarios and compare the expected increase in mortality that results from voluntary versus imposed vaccination. Below a threshold level of post-outbreak vaccination effort, expected mortality is independent of the level of response effort. A lag between an outbreak starting and a response being initiated increases the post-outbreak vaccination effort necessary to reduce mortality. For some post-outbreak vaccination scenarios, even modest response lags make it impractical to reduce mortality by increasing post-outbreak vaccination effort. In such situations, if decreasing the response lag is impossible, the only practical way to reduce mortality is to make the vaccine safer (greater post-outbreak vaccination effort leads only to fewer people vaccinating pre-emptively). PMID:25926701

  11. A screening tool to prioritize public health risk associated with accidental or deliberate release of chemicals into the atmosphere

    PubMed Central

    2013-01-01

    The Chemical Events Working Group of the Global Health Security Initiative has developed a flexible screening tool for chemicals that present a risk when accidentally or deliberately released into the atmosphere. The tool is generic, semi-quantitative, independent of site, situation and scenario, encompasses all chemical hazards (toxicity, flammability and reactivity), and can be easily and quickly implemented by non-subject matter experts using freely available, authoritative information. Public health practitioners and planners can use the screening tool to assist them in directing their activities in each of the five stages of the disaster management cycle. PMID:23517410

  12. A screening tool to prioritize public health risk associated with accidental or deliberate release of chemicals into the atmosphere.

    PubMed

    Blakey, David H; Lafontaine, Marc; Lavigne, Jocelyn; Sokolowski, Danny; Philippe, Jean-Marc; Sapori, Jean-Marc; Biederbick, Walter; Horre, Regine; Marzi, Willi B; Kondo, Hisayoshi; Kuroki, Yumiko; Namera, Akira; Okumura, Tetsu; Yamamoto, Miyako; Yashiki, Mikio; Blain, Peter G; Russell, David R; Cibulsky, Susan M; Jett, David A

    2013-01-01

    The Chemical Events Working Group of the Global Health Security Initiative has developed a flexible screening tool for chemicals that present a risk when accidentally or deliberately released into the atmosphere. The tool is generic, semi-quantitative, independent of site, situation and scenario, encompasses all chemical hazards (toxicity, flammability and reactivity), and can be easily and quickly implemented by non-subject matter experts using freely available, authoritative information. Public health practitioners and planners can use the screening tool to assist them in directing their activities in each of the five stages of the disaster management cycle. PMID:23517410

  13. Analytical Evaluation of Preliminary Drop Tests Performed to Develop a Robust Design for the Standardized DOE Spent Nuclear Fuel Canister

    SciTech Connect

    A.G. Ware; D.K. Morton; N.L. Smith; S.D. Snow; T.E. Rahl

    1999-08-01

    The Department of Energy (DOE) has developed a design concept for a set of standard canisters for the handling, interim storage, transportation, and disposal in the national repository, of DOE spent nuclear fuel (SNF). The standardized DOE SNF canister has to be capable of handling virtually all of the DOE SNF in a variety of potential storage and transportation systems. It must also be acceptable to the repository, based on current and anticipated future requirements. This expected usage mandates a robust design. The canister design has four unique geometries, with lengths of approximately 10 feet or 15 feet, and an outside nominal diameter of 18 inches or 24 inches. The canister has been developed to withstand a drop from 30 feet onto a rigid (flat) surface, sustaining only minor damage - but no rupture - to the pressure (containment) boundary. The majority of the end drop-induced damage is confined to the skirt and lifting/stiffening ring components, which can be removed if de sired after an accidental drop. A canister, with its skirt and stiffening ring removed after an accidental drop, can continue to be used in service with appropriate operational steps being taken. Features of the design concept have been proven through drop testing and finite element analyses of smaller test specimens. Finite element analyses also validated the canister design for drops onto a rigid (flat) surface for a variety of canister orientations at impact, from vertical to 45 degrees off vertical. Actual 30-foot drop testing has also been performed to verify the final design, though limited to just two full-scale test canister drops. In each case, the analytical models accurately predicted the canister response.

  14. Scaling and gender behavior of road accidental dynamics

    NASA Astrophysics Data System (ADS)

    Qiu, Tian; Zou, Xiang-Xiang; Chen, Guang; Jiang, Xiong-Fei; Zhong, Li-Xin

    2014-12-01

    The probability distribution of the time intervals between two consecutive accidents is investigated, based on the road accidental records of the Great Britain. A universal description is obtained for different roads, by rescaling the probability distribution and time intervals. The scaling curve is found to deviate from the Gaussian distribution, but it is well fitted by a stretched exponential function. Long-range time correlation is revealed for the interevent series. Moreover, gender similarity is found for the small accidental intervals, while for the large intervals, the female drivers are observed to present a higher probability than the male drivers.

  15. Accidental inflation from Kähler uplifting

    SciTech Connect

    Ben-Dayan, Ido; Westphal, Alexander; Wieck, Clemens; Jing, Shenglin E-mail: shenglin.jing@utoronto.ca E-mail: clemens.wieck@desy.de

    2014-03-01

    We analyze the possibility of realizing inflation with a subsequent dS vacuum in the Käahler uplifting scenario. The inclusion of several quantum corrections to the 4d effective action evades previous no-go theorems and allows for construction of simple and successful models of string inflation. The predictions of several benchmark models are in accord with current observations, i.e., a red spectral index, negligible non-gaussianity, and spectral distortions similar to the simplest models of inflation. A particularly interesting subclass of models are ''left-rolling'' ones, where the overall volume of the compactified dimensions shrinks during inflation. We call this phenomenon ''inflation by deflation'' (IBD), where deflation refers to the internal manifold. This subclass has the appealing features of being insensitive to initial conditions, avoiding the overshooting problem, and allowing for observable running α ∼ 0.012 and enhanced tensor-to-scalar ratio r ∼ 10{sup −5}. The latter results differ significantly from many string inflation models.

  16. Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-04-01

    Dispersion modeling of accidental releases of toxic gases - Comparison of the models and their utility for the fire brigades. Sirma Stenzel, Kathrin Baumann-Stanzer In the case of accidental release of hazardous gases in the atmosphere, the emergency responders need a reliable and fast tool to assess the possible consequences and apply the optimal countermeasures. For hazard prediction and simulation of the hazard zones a number of air dispersion models are available. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for display the results, they are easy to use and can operate fast and effective during stress situations. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios"), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. There are also possibilities for model direct coupling to automatic meteorological stations, in order to avoid uncertainties in the model output due to insufficient or incorrect meteorological data. Another key problem in coping with accidental toxic release is the relative width spectrum of regulations and values, like IDLH, ERPG, AEGL, MAK etc. and the different criteria for their application. Since the particulate emergency responders and organizations require for their purposes unequal regulations and values, it is quite difficult to predict the individual hazard areas. There are a quite number of research studies and investigations coping with the problem, anyway the end decision is up to the authorities. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Vienna fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program at the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). One of the main tasks of this project was 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. This presentation introduces the project models used and presents the results of task 2. The results of task 1 are presented by Baumann-Stanzer and Stenzel in this session. For the purpose of this study the following models were tested and compared: ALOHA (Areal Location of Hazardous atmosphere, EPA), MEMPLEX (Keudel av-Technik GmbH), Breeze (Trinity Consulting), SAFER System, SAM (Engineering office Lohmeyer), COMPAS. A set of reference scenarios for Chlorine, Ammoniac, Butane and Petrol were proceed in order to reliably predict and estimate the human exposure during the event. The models simulated the accidental release from the mentioned above gases and estimates the potential toxic areas. Since the inputs requirement differ from model to model, and the outputs are based on different criteria for toxic areas and exposure, a high degree of caution in the interpretation of the model results is needed.

  17. Mars base buildup scenarios

    SciTech Connect

    Blacic, J.D.

    1985-01-01

    Two surface base build-up scenarios are presented in order to help visualize the mission and to serve as a basis for trade studies. In the first scenario, direct manned landings on the Martian surface occur early in the missions and scientific investigation is the main driver and rationale. In the second scenario, early development of an infrastructure to exploite the volatile resources of the Martian moons for economic purposes is emphasized. Scientific exploration of the surface is delayed at first, but once begun develops rapidly aided by the presence of a permanently manned orbital station.

  18. The Stability of Two Connected Pendant Drops

    NASA Technical Reports Server (NTRS)

    Slobozhanin, Lev A.; Alexander, J. Iwan

    2004-01-01

    The stability of an equilibrium system of two drops suspended from circular holes is examined. The drop surfaces are disconnected surfaces of a connected liquid body. For holes of equal radii and identical pendant drops axisymmetric perturbations are always the most dangerous. The stability region for two identical drops differs considerably from that for a single drop. Loss of stability leads to a transition from a critical system of identical drops to a stable system of axisymmetric non-identical. This system of non-identical drops reaches its own stability limit (to isochoric or non-isochoric paturbations). For non-identical drops, loss of stability results in dripping or streaming from the holes. Critical volumes for non-identical drops have been calculated as functions of the Bond number, B. For unequal hole radii, stability regions have been constructed for a set of hole radius, K. The dependence of critical volumes on K and B is analyzed.

  19. Drop impact on a fiber

    NASA Astrophysics Data System (ADS)

    Kim, Sung-Gil; Kim, Wonjung

    2016-04-01

    We present the results of a combined experimental and theoretical investigation of drop impact on a thin fiber. Using high-speed videography, we analyze the dynamics of droplet collision with a fiber. Based on the systematic experiments, we identify three outcomes of collision: capturing, single drop falling, and splitting. The outcomes are presented in a regime map, where the regime boundaries are explained through a scale analysis of forces. We also measure the liquid retention on the fiber after the droplet impact. By considering a liquid film on the fiber, we develop a mechanical model that predicts the residual water mass. Our model reveals that the residual mass depends critically on the fiber thickness and less on the impact speed. Our study can be extended to predicting the remaining droplet, critical problems in air filtration, water collection, and fiber coating.

  20. Posterior tibial nerve as a tendon transfer for drop foot reconstruction: a devastating complication.

    PubMed

    Armangil, Mehmet; Basat, H Çağdaş; Bilgin, S Sinan

    2015-01-01

    Iatrogenic peripheral nerve injuries can result from numerous medical procedures, particularly transection, stretching, compression, injections, heat, radiation, and the use of anticoagulant agents. Late diagnosis may lead to atrophy of the motor endplate and result in poor outcomes. We report a case in which the posterior tibial nerve was accidentally sectioned as the posterior tibial tendon for transfer to the anterior tibial tendon in the reconstruction of drop foot. This iatrogenic complication ultimately required foot amputation. Physicians must be aware of the anatomy of the posterior tibial nerve in order to avoid such complications. PMID:25803264

  1. GLOBAL ALTERNATIVE FUTURE SCENARIOS

    EPA Science Inventory

    One way to examine possible future outcomes for environmental protection is through the development and analysis of alternative future scenarios. This type of assessment postulates two or more different paths that social and environmental development might take, using correspond...

  2. Dynamic nozzles for drop generators.

    PubMed

    Castrejón-Pita, J R; Willis, S J; Castrejón-Pita, A A

    2015-11-01

    In this paper, a novel mechanism allowing greater control over the formation of droplets is presented. This is achieved via the use of a dynamic nozzle of adjustable diameter. It is demonstrated that, by using such a nozzle, it is possible to greatly modify the formation and breakup of the ligament behind the main drop, leading to an overall reduction in the number of satellite droplets. Furthermore, by adjusting the delay between the beginning of the forming of the drop and the start of the nozzle constriction, a greater control over both the number of satellites and the size of the main drop can be achieved. It is also shown that only a minimal reduction of the nozzle's effective diameter is required in order to exploit the positive effects of the technique presented here. This opens the possibility of incorporating the technique into current droplet generator systems, e.g., via the use of piezoelectric driven nozzles or other micro-mechanical actuation technology. PMID:26628166

  3. Thermocapillary motion of deformable drops

    NASA Astrophysics Data System (ADS)

    Haj-Hariri, Hossein; Shi, Qingping; Borhan, Ali

    1994-08-01

    The thermocapillary motion of initially spherical drops/bubbles driven by a constant temperature gradient in an unbounded liquid medium is simulated numerically. Effects of convection of momentum and energy, as well as shape deformations, are addressed. The method used is based on interface tracking on a base cartesian grid, and uses a smeared color or indicator function for the determination of the surface topology. Quad-tree adaptive refinement of the cartesian grid is implemented to enhance the fidelity of the surface tracking. It is shown that convection of energy results in a slowing of the drop, as the isotherms get wrapped around the front of the drop. Shape deformation resulting from inertial effects affect the migration velocity. The physical results obtained are in agreement with the existing literature. Furthermore, remarks are made on the sensitivity of the calculated solutions to the smearing of the fluid properties. Analysis and simulations show that the migration velocity depends very strongly on the smearing of the interfacial force whereas it is rather insensitive to the smearing of other properties, hence the adaptive grid.

  4. How to freeze drop oscillations with powders

    NASA Astrophysics Data System (ADS)

    Marston, Jeremy; Zhu, Ying; Vakarelski, Ivan; Thoroddsen, Sigurdur

    2012-11-01

    We present experiments that show when a water drop impacts onto a bed of fine, hydrophobic powder, the final form of the drop can be very different from the spherical form with which it impacts. For all drop impact speeds, the drop rebounds due to the hydrophobic nature of the powder. However, we observe that above a critical impact speed, the drop undergoes a permanent deformation to a highly non-spherical shape with a complete coverage of powder, thus creating a deformed liquid marble. This powder coating acts to freeze the drop oscillations during rebound.

  5. The Accidental Transgressor: Morally-Relevant Theory of Mind

    ERIC Educational Resources Information Center

    Killen, Melanie; Mulvey, Kelly Lynn; Richardson, Cameron; Jampol, Noah; Woodward, Amanda

    2011-01-01

    To test young children's false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N=162) at 3.5, 5.5, and 7.5 years of age were administered three tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an "accidental transgressor" task, which measured a…

  6. Are diabetic foot lesions precipitated by accidental trauma?

    PubMed

    Doshi, H K; Moissinac, K; Harwant, S

    2001-12-01

    Diabetic foot lesions may arise from frictional trauma due to tight or inappropriate footwear, repetitive stresses on parts of the foot, overlying bony prominence generated by walking and accidental trauma to the neuropathic foot. Many diabetics have been found to be unaware of their foot lesion, or know what the precipitating cause was. Based on the assumption that accidental trauma would affect the foot in a random fashion and result in lesions distributed evenly throughout the foot, a study was performed to determine whether foot lesions were distributed evenly or concentrated to certain areas of predilection. It was found that foot lesions were not evenly distributed but concentrated to certain areas of predilection. Even though relatively high proportion of the study population walked about in open slippers and barefeet, the study showed that accidental trauma was not a predominant precipitant of diabetic foot lesions. Diabetic foot lesions tend to occur as a result of cumulative, repetitive trauma to areas of prediliection rather than accidental trauma. PMID:14569763

  7. Accidental entrapment of cats in front-loading washing machines

    PubMed Central

    Stewart, Sarah A.; Gaunt, Matthew C.; Taylor, Susan M.; Snead, Elizabeth C.R.

    2010-01-01

    Two clinical cases of accidental entrapment of cats in front-loading washing machines are described. One cat died the day after presentation as a result of aspiration pneumonia and head trauma, despite supportive care. The second cat survived with supportive treatment, but developed dermatologic complications 10 d later. PMID:21119868

  8. Key-locked guard prevents accidental switch actuation

    NASA Technical Reports Server (NTRS)

    Hawthorne, K. C.

    1966-01-01

    Switch guard, which locks in place on a panel, protects individual switches from accidental activation. The guard consists of a cup to cover the switch lever, a standard screw lock tumbler, and a stud that mates with a threaded adapter in the panel.

  9. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Casualty, Loss, or Theft While in Customs Custody § 158.27 Accidental fire or other casualty. In the case... submitted: (a) A declaration of the master of the vessel, the conductor or driver of the vehicle, the... merchandise was on board the vessel or vehicle, in the warehouse, or otherwise in his charge, as the case...

  10. Distinguishing accidental from inflicted head trauma at autopsy.

    PubMed

    Case, Mary E

    2014-12-01

    This article will discuss accidental and inflicted head injuries in infants and young children and how forensic pathologists distinguish between these types of injuries. The article begins with a consideration of the special and unique features of the anatomy and development of the child's head and neck and then relates these features to the mechanisms of traumatic brain injury and how these unique features influence the mechanisms of injury. The article very specifically notes that accidental head injuries in young children that occur in and around the home are focal head injuries in distinction to inflicted head injuries, which are diffuse brain injuries. The article discusses the mechanisms by which traumatic brain injury causes loss of consciousness and relates those mechanisms to the differences in the clinical features that occur in both accidental and inflicted head injury. The article discusses and illustrates the pathological findings in accidental head injuries consisting of the crushing head injuries and the head injuries sustained in short falls including epidural hemorrhage and focal subdural hemorrhage. The article discusses and illustrates the pathological findings that occur in inflicted head trauma, including subdural and subarachnoid hemorrhages and retinal and optic nerve sheath hemorrhages. PMID:25501735

  11. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Accidental fire or other casualty. 158.27 Section 158.27 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) RELIEF FROM DUTIES ON MERCHANDISE LOST, DAMAGED, ABANDONED, OR EXPORTED Casualty, Loss, or Theft While in...

  12. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Accidental fire or other casualty. 158.27 Section 158.27 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) RELIEF FROM DUTIES ON MERCHANDISE LOST, DAMAGED, ABANDONED, OR EXPORTED Casualty, Loss, or Theft While in...

  13. 19 CFR 158.27 - Accidental fire or other casualty.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Accidental fire or other casualty. 158.27 Section 158.27 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) RELIEF FROM DUTIES ON MERCHANDISE LOST, DAMAGED, ABANDONED, OR EXPORTED Casualty, Loss, or Theft While in...

  14. 49 CFR 192.751 - Prevention of accidental ignition.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Prevention of accidental ignition. 192.751 Section 192.751 Transportation Other Regulations Relating to Transportation (Continued) PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY...

  15. The accidental transgressor: morally-relevant theory of mind.

    PubMed

    Killen, Melanie; Lynn Mulvey, Kelly; Richardson, Cameron; Jampol, Noah; Woodward, Amanda

    2011-05-01

    To test young children's false belief theory of mind in a morally relevant context, two experiments were conducted. In Experiment 1, children (N = 162) at 3.5, 5.5, and 7.5 years of age were administered three tasks: prototypic moral transgression task, false belief theory of mind task (ToM), and an "accidental transgressor" task, which measured a morally-relevant false belief theory of mind (MoToM). Children who did not pass false belief ToM were more likely to attribute negative intentions to an accidental transgressor than children who passed false belief ToM, and to use moral reasons when blaming the accidental transgressor. In Experiment 2, children (N = 46) who did not pass false belief ToM viewed it as more acceptable to punish the accidental transgressor than did participants who passed false belief ToM. Findings are discussed in light of research on the emergence of moral judgment and theory of mind. PMID:21377148

  16. 60,000 U.S. Kids Treated for Accidental Medicine Poisoning a Year

    MedlinePlus

    ... html 60,000 U.S. Kids Treated for Accidental Medicine Poisoning a Year Toddlers account for 7 out ... in the United States are accidentally poisoned by medicines each year, a new report says. That's the ...

  17. Dropping the Bomb in CEDA.

    ERIC Educational Resources Information Center

    Hubbard, Bryan K.

    Given a choice of one argument, most Cross Examination Debate Association (CEDA) competitors would choose the nuclear war scenario, which attempts to capitalize on apocalyptism. A three-stage methodology can be applied to apocalyptic appeals. First is an application of the concept of universal audience, composed of all reasonable and competent…

  18. Attracting Water Drops - Duration: 88 seconds.

    NASA Video Gallery

    Astronauts Cady Coleman and Ron Garan perform the Attracting Water Drops experiment from Chabad Hebrew Academy in San Diego, Calif. This research determines if a free-floating water drop can be att...

  19. BCube Ocean Scenario

    NASA Astrophysics Data System (ADS)

    Santoro, Mattia; Schofield, Oscar; Pearlman, Jay; Nativi, Stefano

    2015-04-01

    To address complex Earth system issues such as climate change and water resources, geoscientists must work across disciplinary boundaries; this requires them to access data outside of their fields. Scientists are being called upon to find, access, and use diverse and voluminous data types that are described with semantics. Within the framework of the NSF EarthCube programme, the BCube project (A Broker Framework for Next Generation Geoscience) is addressing the need for effective and efficient multi-disciplinary collaboration and interoperability through the advancement of brokering technologies. BCube develops science scenarios as key elements in providing an environment for demonstrating capabilities, benefits, and challenges of the developed e-infrastructure. The initial focus is on hydrology, oceans, polar and weather, with the intent to make the technology applicable and available to all the geosciences. This presentation focuses on the BCube ocean scenario. The purpose of this scenario is to increase the understanding of the ocean dynamics through incorporation of a wide range of in-situ and satellite data into ocean models using net primary productivity as the initial variable. The science scenario aims to identify spatial and temporal domains in ocean models, and key ecological variables. Field data sets and remote observations data sets from distributed and heterogeneous systems are accessed through the broker and will be incorporated into the models. In this work we will present the achievements in the development of the BCube ocean scenario.

  20. Scenarios for gluino coannihilation

    NASA Astrophysics Data System (ADS)

    Ellis, John; Evans, Jason L.; Luo, Feng; Olive, Keith A.

    2016-02-01

    We study supersymmetric scenarios in which the gluino is the next-to-lightest supersymmetric particle (NLSP), with a mass sufficiently close to that of the lightest supersymmetric particle (LSP) that gluino coannihilation becomes important. One of these scenarios is the MSSM with soft supersymmetry-breaking squark and slepton masses that are universal at an input GUT renormalization scale, but with non-universal gaugino masses. The other scenario is an extension of the MSSM to include vector-like supermultiplets. In both scenarios, we identify the regions of parameter space where gluino coannihilation is important, and discuss their relations to other regions of parameter space where other mechanisms bring the dark matter density into the range allowed by cosmology. In the case of the non-universal MSSM scenario, we find that the allowed range of parameter space is constrained by the requirement of electroweak symmetry breaking, the avoidance of a charged LSP and the measured mass of the Higgs boson, in particular, as well as the appearance of other dark matter (co)annihilation processes. Nevertheless, LSP masses m χ ≲ 8 TeV with the correct dark matter density are quite possible. In the case of pure gravity mediation with additional vector-like supermultiplets, changes to the anomaly- mediated gluino mass and the threshold effects associated with these states can make the gluino almost degenerate with the LSP, and we find a similar upper bound.

  1. Drag and drop display & builder

    SciTech Connect

    Bolshakov, Timofei B.; Petrov, Andrey D.; /Fermilab

    2007-12-01

    The Drag and Drop (DnD) Display & Builder is a component-oriented system that allows users to create visual representations of data received from data acquisition systems. It is an upgrade of a Synoptic Display mechanism used at Fermilab since 2002. Components can be graphically arranged and logically interconnected in the web-startable Project Builder. Projects can be either lightweight AJAX- and SVG-based web pages, or they can be started as Java applications. The new version was initiated as a response to discussions between the LHC Controls Group and Fermilab.

  2. Drop Tower and Aircraft Capabilities

    NASA Technical Reports Server (NTRS)

    Urban, David L.

    2015-01-01

    This presentation is a brief introduction to existing capabilities in drop towers and low-gravity aircraft that will be presented as part of a Symposium: Microgravity Platforms Other Than the ISS, From Users to Suppliers which will be a half day program to bring together the international community of gravity-dependent scientists, program officials and technologists with the suppliers of low gravity platforms (current and future) to focus on the future requirements and use of platforms other than the International Space Station (ISS).

  3. Nor Any Drop To Drink

    NASA Astrophysics Data System (ADS)

    Lehr, Jay H.

    In Nor Any Drop To Drink author William Ashworth displays an exceptional grasp of the hydrologic cycle for one trained as a writer rather than as an earth scientist. Especially remarkable for a popular book is the no-nonsense manner in which he handles popular misconceptions about underground water. Authors of similar books generally mollify readers who hold fallacious, mysterious beliefs concerning groundwater flow. Ashworth gets their attention with the proverbial two-by-four between the eyes by declaring such fallacies to be 100% hogwash. He describes the groundwater system in an exceptionally accurate manner using precise analogies which benefit from his literary skill.

  4. Electrohydrodynamics of a particle-covered drop

    NASA Astrophysics Data System (ADS)

    Ouriemi, Malika; Vlahovska, Petia

    2014-11-01

    We study the dynamics of a drop nearly-completely covered with a particle monolayer in a uniform DC electric field. The weakly conducting fluid system consists of a silicon oil drop suspended in castor oil. A broad range of particle sizes, conductivities, and shapes is explored. In weak electric fields, the presence of particles increases drop deformation compared to a particle-free drop and suppresses the electrohydrodynamic flow. Very good agreement is observed between the measured drop deformation and the small deformation theory derived for surfactant-laden drops (Nganguia et al., 2013). In stronger electric fields, where drops are expected to undergo Quincke rotation (Salipante and Vlahovska, 2010), the presence of the particles greatly decreases the threshold for rotation and the stationary tilted drop configuration observed for clean drop is replaced by a spinning drop with either a wobbling inclination or a very low inclination. These behaviors resemble the predicted response of rigid ellipsoids in uniform electric fields. At even stronger electric fields, the particles can form dynamic wings or the drop implodes. The similar behavior of particle-covered and surfactant-laden drops provides new insights into understanding stability of Pickering emulsions. Supported by NSF-CBET 1437545.

  5. 49 CFR 178.603 - Drop test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS SPECIFICATIONS FOR PACKAGINGS Testing of Non... each drop) First drop (using three samples): The package must strike the target diagonally on the chime... three samples): The package must strike the target on the weakest part not tested by the first drop,...

  6. 49 CFR 572.102 - Drop test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 7 2011-10-01 2011-10-01 false Drop test. 572.102 Section 572.102 Transportation..., DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Free Motion Headform § 572.102 Drop test. (a) When the headform is dropped from a height of 14.8 inches in accordance with paragraph (b)...

  7. 49 CFR 572.102 - Drop test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 7 2013-10-01 2013-10-01 false Drop test. 572.102 Section 572.102 Transportation..., DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Free Motion Headform § 572.102 Drop test. (a) When the headform is dropped from a height of 14.8 inches in accordance with paragraph (b)...

  8. 49 CFR 178.603 - Drop test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... used for the hydrostatic pressure or stacking test. Exceptions for the number of steel and aluminum... 49 Transportation 3 2011-10-01 2011-10-01 false Drop test. 178.603 Section 178.603 Transportation... Packagings and Packages § 178.603 Drop test. (a) General. The drop test must be conducted for...

  9. Accidental Nuclear War: The Growing Peril. Part I [and] Part II.

    ERIC Educational Resources Information Center

    Newcombe, Alan, Ed.

    1984-01-01

    Two volumes designed to increase awareness of accidental nuclear war dangers are presented. The first of 5 sections in volume I proposes that although accidental war is preventable, the current arms race and secrecy about accidents and false alarms increase the possibility of an accidental war. Section 2 posits that decreased decision-making time…

  10. Dispersion modeling of accidental releases of toxic gases - utility for the fire brigades.

    NASA Astrophysics Data System (ADS)

    Stenzel, S.; Baumann-Stanzer, K.

    2009-09-01

    Several air dispersion models are available for prediction and simulation of the hazard areas associated with accidental releases of toxic gases. The most model packages (commercial or free of charge) include a chemical database, an intuitive graphical user interface (GUI) and automated graphical output for effective presentation of results. The models are designed especially for analyzing different accidental toxic release scenarios ("worst-case scenarios”), preparing emergency response plans and optimal countermeasures as well as for real-time risk assessment and management. The research project RETOMOD (reference scenarios calculations for toxic gas releases - model systems and their utility for the fire brigade) was conducted by the Central Institute for Meteorology and Geodynamics (ZAMG) in cooperation with the Viennese fire brigade, OMV Refining & Marketing GmbH and Synex Ries & Greßlehner GmbH. RETOMOD was funded by the KIRAS safety research program of the Austrian Ministry of Transport, Innovation and Technology (www.kiras.at). The main tasks of this project were 1. Sensitivity study and optimization of the meteorological input for modeling of the hazard areas (human exposure) during the accidental toxic releases. 2. Comparison of several model packages (based on reference scenarios) in order to estimate the utility for the fire brigades. For the purpose of our study the following models were tested and compared: ALOHA (Areal Location of Hazardous atmosphere, EPA), MEMPLEX (Keudel av-Technik GmbH), Trace (Safer System), Breeze (Trinity Consulting), SAM (Engineering office Lohmeyer). A set of reference scenarios for Chlorine, Ammoniac, Butane and Petrol were proceed, with the models above, in order to predict and estimate the human exposure during the event. Furthermore, the application of the observation-based analysis and forecasting system INCA, developed in the Central Institute for Meteorology and Geodynamics (ZAMG) in case of toxic release was investigated. INCA (Integrated Nowcasting through Comprehensive Analysis) data are calculated operationally with 1 km horizontal resolution and based on the weather forecast model ALADIN. The meteorological field's analysis with INCA include: Temperature, Humidity, Wind, Precipitation, Cloudiness and Global Radiation. In the frame of the project INCA data were compared with measurements from the meteorological observational network, conducted at traffic-near sites in Vienna. INCA analysis and very short term forecast fields (up to 6 hours) are found to be an advanced possibility to provide on-line meteorological input for the model package used by the fire brigade. Since the input requirements differ from model to model, and the outputs are based on unequal criteria for toxic area and exposure, a high degree of caution in the interpretation of the model results is required - especially in the case of slow wind speeds, stable atmospheric condition, and flow deflection by buildings in the urban area or by complex topography.

  11. Small drops from large nozzles

    NASA Astrophysics Data System (ADS)

    Castrejon-Pita, Alfonso Arturo; Said Mohamed, Ahmed; Castrejon-Pita, Jose Rafael; Herrada, Miguel Angel

    2015-11-01

    We report experimental and numerical results of the generation of drops which are significantly smaller than the nozzle from which they are generated. The system consists of a cylindrical reservoir and two endplates. One plate is a thin metal sheet with a small orifice in its centre which acts as the nozzle. The other end consists of a piston which moves by the action of an elecromechanical actuator which in turn is driven by sine-shape pull-mode pulses. The meniscus (formed at the nozzle) is thus first overturned, forming a cavity. This cavity collapses and a thin and fast jet emerges from its centre. Under appropriate conditions the tip of this jet breaks up and produces a single diminutive drop. A good agreement between the experimental and numerical results was found. Also, a series of experiments were performed in order to study the effects that the pulse amplitude and width, together with variations in the liquid properties, have over the final size of the droplet. Based on these experiments, a predictive law for the droplet size has been derived. This work was funded by the Royal Society (University Research Fellowship and Research Grant), the John Fell Fund (Oxford University Press), the Ministry of Science and Education (DPI2013-46485 Spain), and the Junta de Andalucia (P08-TEP-31704128 Spain).

  12. Capillary Thinning of Particle-laden Drops

    NASA Astrophysics Data System (ADS)

    Wagoner, Brayden; Thete, Sumeet; Jahns, Matt; Doshi, Pankaj; Basaran, Osman

    2015-11-01

    Drop formation is central in many applications such as ink-jet printing, microfluidic devices, and atomization. During drop formation, a thinning filament is created between the about-to-form drop and the fluid hanging from the nozzle. Therefore, the physics of capillary thinning of filaments is key to understanding drop formation and has been thoroughly studied for pure Newtonian fluids. The thinning dynamics is, however, altered completely when the fluid contains particles, the physics of which is not well understood. In this work, we explore the impact of solid particles on filament thinning and drop formation by using a combination of experiments and numerical simulations.

  13. The SAFRR Tsunami Scenario

    USGS Publications Warehouse

    Porter, K.; Jones, Lucile M.; Ross, Stephanie L.; Borrero, J.; Bwarie, J.; Dykstra, D.; Geist, Eric L.; Johnson, L.; Kirby, Stephen H.; Long, K.; Lynett, P.; Miller, K.; Mortensen, Carl E.; Perry, S.; Plumlee, G.; Real, C.; Ritchie, L.; Scawthorn, C.; Thio, H.K.; Wein, Anne; Whitmore, P.; Wilson, R.; Wood, Nathan J.

    2013-01-01

    The U.S. Geological Survey and several partners operate a program called Science Application for Risk Reduction (SAFRR) that produces (among other things) emergency planning scenarios for natural disasters. The scenarios show how science can be used to enhance community resiliency. The SAFRR Tsunami Scenario describes potential impacts of a hypothetical, but realistic, tsunami affecting California (as well as the west coast of the United States, Alaska, and Hawaii) for the purpose of informing planning and mitigation decisions by a variety of stakeholders. The scenario begins with an Mw 9.1 earthquake off the Alaska Peninsula. With Pacific basin-wide modeling, we estimate up to 5m waves and 10 m/sec currents would strike California 5 hours later. In marinas and harbors, 13,000 small boats are damaged or sunk (1 in 3) at a cost of $350 million, causing navigation and environmental problems. Damage in the Ports of Los Angeles and Long Beach amount to $110 million, half of it water damage to vehicles and containerized cargo. Flooding of coastal communities affects 1800 city blocks, resulting in $640 million in damage. The tsunami damages 12 bridge abutments and 16 lane-miles of coastal roadway, costing $85 million to repair. Fire and business interruption losses will substantially add to direct losses. Flooding affects 170,000 residents and workers. A wide range of environmental impacts could occur. An extensive public education and outreach program is underway, as well as an evaluation of the overall effort.

  14. Biomass Scenario Model

    SciTech Connect

    2015-09-01

    The Biomass Scenario Model (BSM) is a unique, carefully validated, state-of-the-art dynamic model of the domestic biofuels supply chain which explicitly focuses on policy issues, their feasibility, and potential side effects. It integrates resource availability, physical/technological/economic constraints, behavior, and policy. The model uses a system dynamics simulation (not optimization) to model dynamic interactions across the supply chain.

  15. Characterization of maritime scenarios

    NASA Astrophysics Data System (ADS)

    Low, Tom B.; Hudak, D. R.

    1992-09-01

    Meteorological modules were developed to describe characteristic maritime scenarios in various oceanic areas for DREV complimentarity studies of shipboard defense. The best means of depicting the maritime atmospheric environment was found to be on the basis of air mass analysis. A methodology was developed whereby, through a mixture of man-machine objective analysis of upper air radiosonde measurements at the 850, 700, and 500 mb levels, typical airmasses could be identified. Characteristic scenarios were then defined based on physical considerations of air mass theory. Utilizing an extensive 10-year set of worldwide radiosonde, ozondesonde, and surface observations collected from a combination of land-based stations, oceanographic buoys, and weather ships, frequency and correlation statistics of various global and derived meteorological and oceanographic parameters were established for the CANLANT, NORLANT, WESTLANT, EASTLANT, IBERLANT, MARPAC regions, the ARCTIC OCEAN to 85 degree(s)N, the BALTIC SEA, MEDITERRANEAN SEA, PERSIAN GULF, RED SEA, GULF OF OMAN, and the INDIAN OCEAN. These descriptions included atmospheric profiles of pressure, temperature, dewpoint and relative humidity, wind speeds and direction, refractivity index, and ozone concentration from the surface to approximately 20 km., as well as associated surface visibility, clouds and weather, sea state, and duct height conditions. Many of the derived parameters were found to be a strong function of the defining airmass scenarios. The spatial distribution of these scenarios was also determined.

  16. IPCC SCENARIO DATA

    EPA Science Inventory

    This Intergovernmental Panel on Climate Change (IPCC) has made available a consistent set of up-to-date scenarios of changes in climate and related environmental and socio-economic factors for use in climate impacts assessments. This is a link to this data through the Data Distr...

  17. Drop short control of electrode gap

    DOEpatents

    Fisher, Robert W.; Maroone, James P.; Tipping, Donald W.; Zanner, Frank J.

    1986-01-01

    During vacuum consumable arc remelting the electrode gap between a consumable electrode and a pool of molten metal is difficult to control. The present invention monitors drop shorts by detecting a decrease in the voltage between the consumable electrode and molten pool. The drop shorts and their associated voltage reductions occur as repetitive pulses which are closely correlated to the electrode gap. Thus, the method and apparatus of the present invention controls electrode gap based upon drop shorts detected from the monitored anode-cathode voltage. The number of drop shorts are accumulated, and each time the number of drop shorts reach a predetermined number, the average period between drop shorts is calculated from this predetermined number and the time in which this number is accumulated. This average drop short period is used in a drop short period electrode gap model which determines the actual electrode gap from the drop short. The actual electrode gap is then compared with a desired electrode gap which is selected to produce optimum operating conditions and the velocity of the consumable error is varied based upon the gap error. The consumable electrode is driven according to any prior art system at this velocity. In the preferred embodiment, a microprocessor system is utilized to perform the necessary calculations and further to monitor the duration of each drop short. If any drop short exceeds a preset duration period, the consumable electrode is rapidly retracted a predetermined distance to prevent bonding of the consumable electrode to the molten remelt.

  18. Large charged drop levitation against gravity

    NASA Technical Reports Server (NTRS)

    Rhim, Won-Kyu; Chung, Sang Kun; Hyson, Michael T.; Trinh, Eugene H.; Elleman, Daniel D.

    1987-01-01

    A hybrid electrostatic-acoustic levitator that can levitate and manipulate a large liquid drop in one gravity is presented. To the authors' knowledge, this is the first time such large drops (up to 4 mm in diameter in the case of water) have been levitated against 1-gravity. This makes possible, for the first time, many new experiments both in space and in ground-based laboratories, such as 1)supercooling and superheating, 2) containerless crystal growth from various salt solutions or melts, 3) drop dynamics of oscillating or rotating liquid drops, 4) drop evaporation and Rayleigh bursting, and 5) containerless material processing in space. The digital control system, liquid drop launch process, principles of electrode design, and design of a multipurpose room temperature levitation chamber are described. Preliminary results that demonstrate drop oscillation and rotation, and crystal growth from supersaturated salt solutions are presented.

  19. Accidental Thawing of Embryos, Cryopreserved for Transfer. Two Italian cases, Milan and Rome.

    PubMed

    Busardò, Francesco P; Vergallo, Gianluca Montanari; Turillazzi, Emanuela; Bolino, Giorgio; Vullo, Annamaria; Frati, Paola

    2016-01-01

    The bioethical and juridical debate on the status of frozen embryos sometimes adds new issues arising from new scientific evidence or by accidental occurrences that bring to the attention of the scientific community the need for new practical solutions. Within this scenario, there have been, in recent years, episodes concerning the accidental thawing of embryos, which have been cryopreserved for transfer. Two Italian cases (the Milan and the Rome cases) are here reported: the Milan case involves a couple undergoing artificial insemination. Three eggs were collected for insemination and two of them had been fertilized. During the night of 8/9 May 2007 a short circuit occurred, resulting in an electricity blackout, which caused the loss of the embryos in culture, which should have been transferred to the woman's uterus on 9 May. The couple applied for damage compensation from the hospital following the loss of the embryos. The case went to Court and the result was a judgment issued by the Milan civil court, which recognized that the centre was to blame for irreparable damage to the embryos. The Rome case, involves two couples (A and B) affected by sterility who applied to an authorized public centre to undergo an ART program. Following the medical procedures, two of the embryos produced were transferred to the woman in couple A and five were frozen, whereas three embryos produced by couple B were transferred to the uterus of the woman and six eggs were cryopreserved in the centre. Two years after the procedure there was an electricity blackout, and the backup electricity generator failed to function, causing the loss of the gametes and the embryos cryopreserved in the centre. Legal proceedings begun by the couples to obtain compensation for damages are still underway. The above reported cases have significantly intensified the bioethical debate on the lawfulness of such practices and on the fate of the cryopreserved embryos, at the same time opening new frontiers in defining the type of damage caused by the accidental destruction of cryopreserved embryos destined for transfer. PMID:26718920

  20. Accidental intraoral injection of formalin during extraction: case report.

    PubMed

    Swami, Pushp Chander; Raval, Rushik; Kaur, Mandeep; Kaur, Jasleen

    2016-04-01

    Transparent, clear solutions such as hydrogen peroxide, alcohol, sodium hypochlorite, formaldehyde, and local anaesthetics are widely used in dentistry, so the tissues are liable to accidental injury. Formalin, a 37%-40% solution of formaldehyde, is extensively used in 10% solution as a tissue preservative, but it has toxic effects on systems such as the gastrointestinal tract, respiratory tract, skin, and mucosa. However, we know of few reports of cases of inadvertent injection of alcohol and formalin directly into the human body. In this case report we describe the early and delayed clinical effects of accidental intraoral injection of formalin, the subsequent symptoms and management, and some prudent points that should be learnt to avoid such incidents in the future. PMID:26794082

  1. Accidental degeneracy of double Dirac cones in a phononic crystal

    PubMed Central

    Chen, Ze-Guo; Ni, Xu; Wu, Ying; He, Cheng; Sun, Xiao-Chen; Zheng, Li-Yang; Lu, Ming-Hui; Chen, Yan-Feng

    2014-01-01

    Artificial honeycomb lattices with Dirac cone dispersion provide a macroscopic platform to study the massless Dirac quasiparticles and their novel geometric phases. In this paper, a quadruple-degenerate state is achieved at the center of the Brillouin zone in a two-dimensional honeycomb lattice phononic crystal, which is a result of accidental degeneracy of two double-degenerate states. In the vicinity of the quadruple-degenerate state, the dispersion relation is linear. Such quadruple degeneracy is analyzed by rigorous representation theory of groups. Using method, a reduced Hamiltonian is obtained to describe the linear Dirac dispersion relations of this quadruple-degenerate state, which is well consistent with the simulation results. Near such accidental degeneracy, we observe some unique properties in wave propagating, such as defect-insensitive propagating character and the Talbot effect. PMID:24714512

  2. Analysis for Eccentric Multi Canister Overpack (MCO) Drops at the Canister Storage Building (CSB) (CSB-S-0073)

    SciTech Connect

    HOLLENBECK, R.G.

    2000-06-07

    The purpose of this report is to investigate the potential for damage to the multi-canister overpack (MCO) during impact from an eccentric accidental drop onto the standard storage tube, overpack storage tube, service station or sampling/weld station. Damage to the storage tube and sample/weld station is beyond the scope of this report. The results of this analysis are required to show the following: (1) If a breach resulting in unacceptable release of contamination could occur in the MCO. (2) If the dropped MCO could become stuck in the storage tube after the drop. (3) Maximum deceleration of the spent nuclear fuel baskets. The model appropriate for the standard storage tubes with the smaller gap is the basis for the analysis and results reported herein in this SNF-5204, revision 2 report. Revision 1 of this report is based on a model that includes the larger gap appropriate for the overpack tubes.

  3. Approaches for preventing and mitigating accidental gaseous chemical releases

    SciTech Connect

    Fthenakis, V.M.

    1996-12-31

    This paper presents a review of approaches to prevent and mitigate accidental releases of toxic and flammable gases. The prevention options are related to: choosing safer processes and materials, preventing initiating events, preventing or minimizing releases, and preventing human exposures. the mitigation options include: secondary confinement, de-inventory, vapor barriers, and water sprays/monitors. Guidelines for the design and operation of effective post-release mitigation systems are also presented.

  4. A case of accidental ingestion of ant bait containing fipronil.

    PubMed

    Fung, Hin Tat; Chan, Kar Ki; Ching, Wei Ming; Kam, Chak Wah

    2003-01-01

    A 77-year-old woman accidentally ingested a commercial ant bait containing fipronil without development of obvious toxicity, supporting the safety of this new insecticide as demonstrated in animal studies. However, concentrated agricultural products may be more toxic, and the potential for seizures should not be overlooked. The pharmacological action, mechanism of selective insect toxicity, and clinical effects of fipronil are discussed. PMID:12807306

  5. Methadone poisoning due to accidental contamination of prescribed medication.

    PubMed Central

    Roland, E H; Lockitch, G; Dunn, H G; Peacock, D; Pirie, G E

    1984-01-01

    Two infants presented with fever and signs of brainstem dysfunction, including impaired consciousness, miosis, absence of oculocephalic responses, respiratory depression and a very peculiar tremor of the tongue and floor of the mouth. They were found to have methadone poisoning caused by accidental contamination of prescribed antibiotics in the same pharmacy, which was a dispensing centre for a methadone maintenance program. They recovered with supportive treatment only. PMID:6498687

  6. Paediatric femur fractures at the emergency department: accidental or not?

    PubMed

    Hoytema van Konijnenburg, Eva Mm; Vrolijk-Bosschaart, Thekla F; Bakx, Roel; Van Rijn, Rick R

    2016-05-01

    Only a small proportion of all paediatric fractures is caused by child abuse or neglect, especially in highly prevalent long bone fractures. It can be difficult to differentiate abusive fractures from non-abusive fractures. This article focuses on femoral fractures in young children. Based on three cases, this article presents a forensic evidence-based approach to differentiate between accidental and non-accidental causes of femoral fractures. We describe three cases of young children who were presented to the emergency department because of a suspected femur fracture. Although in all cases, the fracture had a similar location and appearance, the clinical history and developmental stage of the child led to three different conclusions. In the first two cases, an accidental mechanism was a plausible conclusion, although in the second case, neglect of parental supervision was the cause for concern. In the third case, a non-accidental injury was diagnosed and appropriate legal prosecution followed. Any doctor treating children should always be aware of the possibility of child abuse and neglect in children with injuries, especially in young and non-mobile children presenting with an unknown trauma mechanism. If a suspicion of child abuse or neglect arises, a thorough diagnostic work-up should be performed, including a full skeletal survey according to the guidelines of the Royal College of Radiologists and the Royal College of Paediatrics and Child Health. In order to make a good assessment, the radiologist reviewing the skeletal survey needs access to all relevant clinical and social information. PMID:26642309

  7. Prevention of accidental exposure in radiotherapy: the risk matrix approach.

    PubMed

    Vilaragut, J J; Duménigo, C; Delgado, J M; Morales, J; McDonnell, J D; Ferro, R; Ortiz López, P; Ramírez, M L; Pérez Mulas, A; Papadopulos, S; Gonçalves, M; López Morones, R; Sánchez Cayuela, C; Cascajo Castresana, A; Somoano, F; Álvarez, C; Guillén, A; Rodríguez, M; Pereira, P P; Nader, A

    2013-02-01

    Knowledge and lessons from past accidental exposures in radiotherapy are very helpful in finding safety provisions to prevent recurrence. Disseminating lessons is necessary but not sufficient. There may be additional latent risks for other accidental exposures, which have not been reported or have not occurred, but are possible and may occur in the future if not identified, analyzed, and prevented by safety provisions. Proactive methods are available for anticipating and quantifying risk from potential event sequences. In this work, proactive methods, successfully used in industry, have been adapted and used in radiotherapy. Risk matrix is a tool that can be used in individual hospitals to classify event sequences in levels of risk. As with any anticipative method, the risk matrix involves a systematic search for potential risks; that is, any situation that can cause an accidental exposure. The method contributes new insights: The application of the risk matrix approach has identified that another group of less catastrophic but still severe single-patient events may have a higher probability, resulting in higher risk. The use of the risk matrix approach for safety assessment in individual hospitals would provide an opportunity for self-evaluation and managing the safety measures that are most suitable to the hospital's own conditions. PMID:23274816

  8. An alternative approach for computing seismic response with accidental eccentricity

    NASA Astrophysics Data System (ADS)

    Fan, Xuanhua; Yin, Jiacong; Sun, Shuli; Chen, Pu

    2014-09-01

    Accidental eccentricity is a non-standard assumption for seismic design of tall buildings. Taking it into consideration requires reanalysis of seismic resistance, which requires either time consuming computation of natural vibration of eccentric structures or finding a static displacement solution by applying an approximated equivalent torsional moment for each eccentric case. This study proposes an alternative modal response spectrum analysis (MRSA) approach to calculate seismic responses with accidental eccentricity. The proposed approach, called the Rayleigh Ritz Projection-MRSA (RRP-MRSA), is developed based on MRSA and two strategies: (a) a RRP method to obtain a fast calculation of approximate modes of eccentric structures; and (b) an approach to assemble mass matrices of eccentric structures. The efficiency of RRP-MRSA is tested via engineering examples and compared with the standard MRSA (ST-MRSA) and one approximate method, i.e., the equivalent torsional moment hybrid MRSA (ETM-MRSA). Numerical results show that RRP-MRSA not only achieves almost the same precision as ST-MRSA, and is much better than ETM-MRSA, but is also more economical. Thus, RRP-MRSA can be in place of current accidental eccentricity computations in seismic design.

  9. Population trajectories for accidental versus planned colonisation of islands.

    PubMed

    Ruxton, Graeme D; Wilkinson, David M

    2012-09-01

    We modify an existing model of the population trajectory on an island after the first arrival of a group of hominins to compare the potential success rates of accidental arrival (e.g., on vegetation rafts following major floods or a tsunami) against planned colonisation by watercraft. Our model predicts that colonisation through the accidental arrival of a group of individuals on an island should be around half as likely to be successful as colonisation through the arrival of a planned voyaging party of the same size, but that this difference could be entirely counteracted by the infrequent arrival of small numbers of individuals by similar accidental circumstances in the centuries after the initial colonisation. We argue that our model investigations strengthen the plausibility that especially early island colonisation (such as Homo erectus on Flores) may have occurred as a result of highly anomalous natural events (such as a tsunami), and thus hominin colonisation of islands outside swimming range of continents should not be seen as necessarily indicating the existences of seafaring technologies and skills. PMID:22748511

  10. Dynamics of Aqueous Foam Drops

    NASA Technical Reports Server (NTRS)

    Akhatov, Iskander; McDaniel, J. Gregory; Holt, R. Glynn

    2001-01-01

    We develop a model for the nonlinear oscillations of spherical drops composed of aqueous foam. Beginning with a simple mixture law, and utilizing a mass-conserving bubble-in-cell scheme, we obtain a Rayleigh-Plesset-like equation for the dynamics of bubbles in a foam mixture. The dispersion relation for sound waves in a bubbly liquid is then coupled with a normal modes expansion to derive expressions for the frequencies of eigenmodal oscillations. These eigenmodal (breathing plus higher-order shape modes) frequencies are elicited as a function of the void fraction of the foam. A Mathieu-like equation is obtained for the dynamics of the higher-order shape modes and their parametric coupling to the breathing mode. The proposed model is used to explain recently obtained experimental data.

  11. Rosace patterns in drop impact

    NASA Astrophysics Data System (ADS)

    Lagubeau, Guillaume; Fontelos, Marco; Josserand, Christophe; Maurel, Agns; Pagneux, Vincent; Petitjeans, Philippe

    2010-11-01

    We report an experimental study of the instability of the corolla for drop impacts on liquid surface for moderate Weber numbers (We) and millimetric liquid layers (of thickness h), where no splash is observed. Thanks to a Fourier Transform Profilometry technique (FTP), we exhibit and analyze for the first time the formation of a rosace-like pattern originated from an hydrodynamic instability. Using the shallow water approximation, we explain the main mechanisms leading to these patterns: it consists in the linear instability of the self-similar axisymmetric radial solution of the equations. We found that the number of folds scales like We/h at the power 2/7 as observed in our experiments.

  12. Magnetically focused liquid drop radiator

    DOEpatents

    Botts, Thomas E.; Powell, James R.; Lenard, Roger

    1986-01-01

    A magnetically focused liquid drop radiator for application in rejecting rgy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  13. Magnetically focused liquid drop radiator

    DOEpatents

    Botts, T.E.; Powell, J.R.; Lenard, R.

    1984-12-10

    A magnetically focused liquid drop radiator for application in rejecting energy from a spacecraft, characterized by a magnetizable liquid or slurry disposed in operative relationship within the liquid droplet generator and its fluid delivery system, in combination with magnetic means disposed in operative relationship around a liquid droplet collector of the LDR. The magnetic means are effective to focus streams of droplets directed from the generator toward the collector, thereby to assure that essentially all of the droplets are directed into the collector, even though some of the streams may be misdirected as they leave the generator. The magnetic focusing means is also effective to suppress splashing of liquid when the droplets impinge on the collector.

  14. Micro-explosion of compound drops

    NASA Astrophysics Data System (ADS)

    Chen, Chun-Kuei; Lin, Ta-Hui

    2014-08-01

    Introducing water into spray combustion systems, by either water-in-oil emulsification or supplementary water injection, is one of the major techniques for combustion improvement and NOx reduction. Plentiful researches are available on combustion of water-in-oil emulsion fuel drops. The emulsified liquid is a heterogeneous mixture of immiscible liquids. One component forms the continuous phase and the other component forms the discrete phase. The discrete phase consists of globules of the one fluid that are suspended in the continuous phase fluid. Water-in-oil emulsions are commonly considered for combustion applications because emulsions can result in micro-explosion, thereby reducing the average drop diameter to enhance liquid vaporization, and suppressing the formation of soot and NOx. However, the water addition generally does not exceed about 20% for smooth engine operations[!, 21. The combustion characteristics and micro-explosion of emulsion drop were studied by many researchers. The micro-explosion of water in fuel emulsion drops was caused by very fast growth of superheated water vapor bubbles, its superheat limits must be lower than the boiling point temperature of the fuel. These bubbles were primarily governed by the pressure difference between the superheated vapor and the liquid, and by the inertia imparted to the liquid by the motion of the bubble surface[3 6 In this study, we used a coaxial nozzle to generation the multi-component drop. The different type of water-in-oil fuel drops called the compound drops. Unlike an emulsion drop, a compound drop consists of a water core and a fuel shell, which can originate from the phase separation of emulsion[7, 81 or a water drop colliding with a fuel drop[9, 101 Burning and micro-explosion of compound drops have been found to be distinct from those of emulsion drops[9-111 Wang et al.[9 , 101 studied the combustion characteristics of collision merged alkane-water drops. The merged drops appeared in adhesive and inserted manners. The drop ignition delay time increased with increasing water content. The average burning rate of alkane-water drops decreased with increasing water content. In the burning process, hexadecane-water drops exhibited flash vaporization or flame extinction. Heterogeneous explosion was occasionally observed in drops with trapped air bubbles. The air bubbles were assumed to be the nucleation points of the heterogeneous explosions. Chen and Lin[11 studied the characteristics of water-in-dodecane compound drop with different water content, diameter of drop and environmental oxygen concentration. The vaporization rate increased with increasing environmental oxygen concentration. The compound drops micro-exploded during the burning process in a random way. The number of micro-explosions was majorly influenced by drop diameter, followed by environmental oxygen concentration. Water content had a weaker effect on micro-explosion. As available literature and research results of compound drop burning are scarce, their combustion and micro-explosion behaviors are still poorly understood. In this regard, we changed the drop nature as compound drops to study their combustion characteristics and micro-explosion phenomena.

  15. Non-coalescence of oppositely charged drops.

    PubMed

    Ristenpart, W D; Bird, J C; Belmonte, A; Dollar, F; Stone, H A

    2009-09-17

    Electric fields induce motion in many fluid systems, including polymer melts, surfactant micelles and colloidal suspensions. Likewise, electric fields can be used to move liquid drops. Electrically induced droplet motion manifests itself in processes as diverse as storm cloud formation, commercial ink-jet printing, petroleum and vegetable oil dehydration, electrospray ionization for use in mass spectrometry, electrowetting and lab-on-a-chip manipulations. An important issue in practical applications is the tendency for adjacent drops to coalesce, and oppositely charged drops have long been assumed to experience an attractive force that favours their coalescence. Here we report the existence of a critical field strength above which oppositely charged drops do not coalesce. We observe that appropriately positioned and oppositely charged drops migrate towards one another in an applied electric field; but whereas the drops coalesce as expected at low field strengths, they are repelled from one another after contact at higher field strengths. Qualitatively, the drops appear to 'bounce' off one another. We directly image the transient formation of a meniscus bridge between the bouncing drops, and propose that this temporary bridge is unstable with respect to capillary pressure when it forms in an electric field exceeding a critical strength. The observation of oppositely charged drops bouncing rather than coalescing in strong electric fields should affect our understanding of any process involving charged liquid drops, including de-emulsification, electrospray ionization and atmospheric conduction. PMID:19759616

  16. Why Chalk Breaks into Three Pieces When Dropped

    NASA Astrophysics Data System (ADS)

    Cross, Rod

    2015-01-01

    It has been the author's experience over many years, no doubt shared by others, that a stick of chalk usually breaks into three pieces when accidentally dropped onto the floor. I rarely gave it any thought, apart from noting that the fundamental mode of vibration of a freely supported, rigid rod has two nodes at an equal distance from each end. For example, a baseball bat has a node in the barrel (the sweet spot) about 15 cm from the end and another node in the handle. However, chalk is not expected to break at the node points, since maximum stress arises at the antinode in the middle of the chalk where bending is a maximum. Richard Feynman described a similar problem with long sticks of spaghetti.1 He found that they always break into three or more pieces when bent slowly beyond their breaking point, rather than simply breaking in half. He was unable to figure out why, although the problem was solved many years later2 and is nicely illustrated by Vollmer and Mollmann.3

  17. Ultrasonic tracking of ply drops in composite laminates

    NASA Astrophysics Data System (ADS)

    Smith, Robert A.; Nelson, Luke J.; Mienczakowski, Martin J.; Wilcox, Paul D.

    2016-02-01

    As the shapes of composite components become more adventurous, tracking internal locations of ply drops and detecting any tape gaps or overlaps will be crucial to assure conformance to design. The true potential of ultrasound has yet to be exploited for this objective due to the apparent complexity of the ultrasonic response and the assumption that interference between signals from plies is random, confusing and of little use. As a result, most ultrasonic inspection of composites targets defects that either attenuate or reflect ultrasound, regarding ply reflections as undesirable `noise'. The work presented here extends the ply-orientation mapping of the last two decades by introducing a systematic approach to optimizing the ultrasonic response from the plies, minimizing interference between plies and demonstrating that accurate maps of plies through ply-drop regions can be produced. The key to this method is understanding the ultrasonic analytic signal and how it interacts with plies and the resin-rich layers between them. In certain circumstances of frequency and bandwidth, the instantaneous phase locks onto the resin-rich layers and the instantaneous amplitude indicates the validity of this condition. Analytical modelling is used to explain the interaction between ultrasound and composite plies in various ply-drop scenarios, with reference to experimental results. Optimization of ultrasonic data acquisition is also discussed and demonstrated experimentally.

  18. Bubbles and drops on curved surfaces.

    PubMed

    Soleimani, Majid; Hill, Reghan J; van de Ven, Theo G M

    2013-11-19

    Surface curvature affects the shape, stability, and apparent contact angle of sessile and pendant drops. Here, we develop an approximate analytical solution for non-axisymmetric perturbations to small spherical drops on a flat substrate, assuming a fixed contact angle and fixed drop volume. The analytical model is validated using numerical solutions of the Laplace equation from the Surface Evolver software. We investigate the effects of surface curvature on drop shape, pressure, and surface energy, ascertaining the energy-gradient force that drives lateral drop migration. By balancing this force with the viscous resistance/drag force, in the lubrication approximation, we predict velocities of the order of 0.1 mm s(-1) for 1 mm diameter drops of water with a 30° contact angle on a substrate with a curvature gradient of 0.01 mm(-2), achieved, for example, on a harmonic surface with a wavelength of 4 cm and an amplitude of 4 mm. PMID:24093829

  19. Generation of inkjet drop of particulate gel

    NASA Astrophysics Data System (ADS)

    Yoo, Hansol; Kim, Chongyoup

    2015-08-01

    The generation of inkjet drops of colloidal gels is studied experimentally. Particle suspensions are prepared by dispersing spherical polystyrene particles of 620 nm in the 1:1 mixture of deionized water and ethylene glycol. The gels are prepared by adding polyethylene oxide to the suspensions by inducing the depletion interaction between particles. It is demonstrated that inkjet drops can be generated by using the colloidal gels. It is found that the ligament extended from the inkjet nozzle is stabilized so that the drop can be generated without satellite droplets behind the main drop and the velocity of the gel drop is faster than that of the polymer solution at the same concentration. The gel drop generation characteristics are found to be sensitive to input voltage.

  20. Coalescence dynamics of viscous conical drops

    NASA Astrophysics Data System (ADS)

    Lu, Jiakai; Fang, Shengyang; Corvalan, Carlos M.

    2016-02-01

    When two oppositely charged drops come into light contact, a liquid meniscus bridge with double-cone geometry forms between the drops. Recent experiments have demonstrated the existence of a critical cone angle above which the meniscus bridge pinches off and the drops do not coalesce. This striking behavior—which has implications for processes ranging from the coarsening of emulsions to electrospray ionization in mass spectrometry—has been studied theoretically and experimentally for inertial liquid drops. Little is known, however, about the influence of the liquid viscosity on the critical cone angle. Here, we use high-fidelity numerical simulations to gain insight into the coalescence dynamics of conical drops at intermediate Reynolds numbers. The simulations, which account for viscous, inertial, and surface tension effects, predict that the critical cone angle increases as the viscosity of the drops decreases. When approaching the inertial regime, however, the predicted critical angle quickly stabilizes at approximately 27∘, as observed in experiments.

  1. Drop Shaping by Laser-Pulse Impact

    NASA Astrophysics Data System (ADS)

    Klein, Alexander L.; Bouwhuis, Wilco; Visser, Claas Willem; Lhuissier, Henri; Sun, Chao; Snoeijer, Jacco H.; Villermaux, Emmanuel; Lohse, Detlef; Gelderblom, Hanneke

    2015-04-01

    We show how the deposition of laser energy induces propulsion and strong deformation of an absorbing liquid body. Combining high speed with stroboscopic imaging, we observe that a millimeter-sized dyed water drop hit by a millijoule nanosecond laser pulse propels forward at several meters per second and deforms until it eventually fragments. The drop motion results from the recoil momentum imparted at the drop surface by water vaporization. We measure the propulsion speed and the time-deformation law of the drop, complemented by boundary-integral simulations. The drop propulsion and shaping are explained in terms of the laser-pulse energy, the drop size, and the liquid properties. These findings are, for instance, crucial for the generation of extreme ultraviolet light in nanolithography machines.

  2. Surface-Controlled Drop Oscillations in Space

    NASA Technical Reports Server (NTRS)

    Holt, R. Glynn; Tian, Yuren; Janovsky, Joseph; Apfel, Robert E.

    1996-01-01

    Large liquid drops were deformed by an acoustic standing wave in a resonant air chanber called the Drop Physics Module, which was carried on Space Shuttle Columbia as part of the second United States Microgravity Laboratory mission. When this deforming force was suddenly reduced, the drops executed free oscillations about a perfect sherical equilibrium. Results are presented for pure water and aqueous solutions of soluble surfactants. [PACS: 43.25.U, 47.55Dz, 68.10.Cr, 83.10.-y].

  3. Drop Tower Experiments concerning Fluid Management under Microgravity

    NASA Astrophysics Data System (ADS)

    Gaulke, Diana; Dreyer, Michael

    2012-07-01

    Transport and positioning of liquid under microgravity is done utilizing capillary forces. Therefore, capillary transport processes have to be understood for a wide variety of space applications, ranging from propellant management in tanks of space transportation systems to eating and drinking devices for astronauts. There are two types of liquid transportation in microgravity using capillary forces. First, the driven liquid flow in open channels where the capillary forces at free surfaces ensure a gas and vapor free flow. Here it is important to know the limiting flow rate through such an open channel before the free surface collapses and gas is sucked into the channel. A number of different experiments at the drop tower Bremen, on sounding rockets and at the ISS have been conducted to analyse this phenomenon within different geometries. As result a geometry dependent theory for calculating the maximum flow rate has been found. On the other hand liquid positioning and transportation requires the capillary pressure of curved surfaces to achieve a liquid flow to a desired area. Especially for space applications the weight of structure has to be taken into account for development. For example liquid positioning in tanks can be achieved via a complicated set of structure filling the whole tank resulting in heavy devices not reasonable in space applications. Astrium developed in cooperation with ZARM a propellant management device much smaller than the tank volume and ensuring a gas and vapour free supply of propellant to the propulsion system. In the drop tower Bremen a model of this device was tested concerning different microgravity scenarios. To further decrease weight and ensure functionality within different scenarios structure elements are designed as perforated geometries. Capillary transport between perforated plates has been analyzed concerning the influence of geometrical pattern of perforations. The conducted experiments at the drop tower Bremen show the remarkable influence of perforations on the capillary transport capability.

  4. Drop motion induced by vertical vibrations

    NASA Astrophysics Data System (ADS)

    Sartori, Paolo; Quagliati, Damiano; Varagnolo, Silvia; Pierno, Matteo; Mistura, Giampaolo; Magaletti, Francesco; Massimo Casciola, Carlo

    2015-11-01

    We have studied the motion of liquid drops on an inclined plate subject to vertical vibrations. The liquids comprised distilled water and different aqueous solutions of glycerol, ethanol and isopropanol spanning the range 1-39 mm2 s-1 in kinematic viscosities and 40-72 mN m-1 in surface tension. At sufficiently low oscillating amplitudes, the drops are always pinned to the surface. Vibrating the plate above a certain amplitude yields sliding of the drop. Further increasing the oscillating amplitude drives the drop upward against gravity. In the case of the most hydrophilic aqueous solutions, this motion is not observed and the drop only slides downward. Images taken with a fast camera show that the drop profile evolves in a different way during sliding and climbing. In particular, the climbing drop experiences a much bigger variation in its profile during an oscillating period. Complementary numerical simulations of 2D drops based on a diffuse interface approach confirm the experimental findings. The overall qualitative behavior is reproduced suggesting that the contact line pinning due to contact angle hysteresis is not necessary to explain the drop climbing.

  5. Videographic Assessment of Glaucoma Drop Instillation

    PubMed Central

    Castillejos, Armando; Kahook, Malik; Jimenez-Roman, Jesus; Gonzalez-Salinas, Roberto

    2015-01-01

    ABSTRACT Purpose: To assess the effect of patient education on videotaped topical instillation of artificial tear drops on subsequent topical instillation. Materials and methods: Forty-five patients, who had been using glaucoma drops for at least 6 months and with a best-corrected visual acuity of 20/100 or better, were studied. The patients were asked to instill an artificial tear drop using their accustomed technique while being video recorded. The patients viewed the recordings, and the errors in their drop instillation method were pointed out. This was followed by an educational session on proper drop instillation technique. After 30 minutes, patients were videotaped instilling drops to ascertain the effect of the educational session. The variables compared were: number of drops instilled, number of drops reaching the ocular surface, and the number of times the tip of the medication bottle touched the eye or ocular adnexa. Results: Before the instruction session, patients squeezed an average of 1.5 ± 0.9 drops from the bottle, and the average number of drops reaching the conjunctival fornix was 0.9 ± 0.7. The tip of the bottle touched the ocular adnexa in 29/45 (64.4%) patients. After the education session, the patients squeezed an average of 1.2 ± 0.5 drops and an average of 1.2 ± 0.4 drops reached the conjunctival fornix. The tip of the bottle touched the ocular adnexa in 13/45 (28.9%) patients. With proper instructions, the percentage of patients that instilled just one drop on the eye increased from 66 to 82%. Conclusion: A single educational session on the proper use of topical drops improves the successful instillation of eye drops. However, it was not determined whether the patients will retain the improved instillation technique for long-term or if the intervention results in only a short-term improvement. How to cite this article: Lazcano-Gomez G, Castillejos A, Kahook M, Jimenez-Roman J, Gonzalez-Salinas R. Video-graphic Assessment of Glaucoma Drop Instillation. J Curr Glaucoma Pract 2015;9(2):47-50.

  6. Rapid Drop Dynamics During Superhydrophobic Condensation

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaodong; Boreyko, Jonathan; Chen, Chuan-Hua

    2008-11-01

    Rapid drop motion is observed on superhydrophobic surfaces during condensation; condensate drops with diameter of order 10 μm can move at above 100G and 0.1 m/s. When water vapor condenses on a horizontal superhydrophobic surface, condensate drops move in a seemingly random direction. The observed motion is attributed to the energy released through coalescence of neighboring condensate drops. A scaling analysis captured the initial acceleration and terminal velocity. Our work is a step forward in understanding the dynamics of superhydrophobic condensation occurring in both natural water-repellant plants and engineered dropwise condensers.

  7. Impact force of a falling drop

    NASA Astrophysics Data System (ADS)

    Soto, Dan; Clanet, Cristophe; Quere, David; Xavier Boutillon Collaboration

    2012-11-01

    Controlling droplet deposition is crucial in many industrial processes such as spraying pesticides on crops, inkjet printing or spray coating. Therefore, the dynamics of drop impacts have been extensively studied for more than one century. However, few literature describe the impacting force of a drop on a solid flat surface, although it might be a way to measure the size distribution of a collection of falling drops. We investigated experimentally how the instantaneous force at impact depends on impact velocity and drop radius. We also propose a new model to understand our observations. Physique et Mecanique des Milieux Heterogenes, CNRS, ESPCI, Paris France & Ladhyx, CNRS, Ecole Polytechnique, Palaiseau, France.

  8. Technology of eye drops containing metronidazole.

    PubMed

    Kodym, Anna; Kaczyńska-Dyba, Ewelina; Kubiak, Bartłomiej; Kukuła, Helena

    2011-01-01

    The aim of the studies was to determine the stability of metronidazole using UV spectrophotometric method in 0.5% w/w eye drops which were prepared under aseptic conditions and thermally sterilized. 0.9% solution of NaCl, 5% glucose and phosphate buffers of pH 6.97 and 6.81 were used as the solvents of metronidazole in the drops. Thiomersal and phenylmercuric borate were used to preserve the drops. The viscosity of the eye drops was increased using the solution of polyvinyl alcohol. The drops were stored in tightly closed glass infusion bottles, protected from light. For the stability of analysis a long-term assay was used under controlled conditions following the requirements of ICH, i.e., the time of storage was 24 months at the constant temperature of 25 +/- 2 degrees C and constant humidity of 60% +/- 2% RH. The eye drops containing metronidazole were significantly physically and chemically stable: after 24 months of storage the metronidazole concentration in the drops was close to 100% of the initial concentration. The drops were colorless and transparent. Physical and chemical properties such as pH, osmotic pressure and viscosity underwent insignificant changes during the storage. The preservation test showed that the degree of reduction of the pharmacopeal strains of micro-organisms in freshly prepared drops and in those stored for 24 months at the temperature of 25 +/- 20 degrees C was in agreement with the requirements of Ph. Eur. 6. PMID:21485708

  9. Liquid drop model and heavy ion collisions

    SciTech Connect

    El-Nadi, M.; Hashem, A.

    1981-06-01

    A macroscopic liquid drop model is considered in order to demonstrate the deep inelastic processes that take place in heavy ion collisions. The colliding nuclei, treated as two liquid drops, are assumed to form a single rotating and vibrating compound drop. This drop will either separate again into the parent nuclei, in addition to some smaller particles (satellites), or will form an equilibrium compound nucleus which decays either by particle evaporation or through fission. The maximum and minimum values of the critical angular momentum between which complete fusion occurs are calculated according to this model for several heavy ion reactions and good agreement with the experimental values is observed.

  10. Non-coalescence of oppositely charged drops

    NASA Astrophysics Data System (ADS)

    Ristenpart, W. D.; Bird, J. C.; Belmonte, A.; Dollar, F.; Stone, H. A.

    2009-11-01

    Electrically induced droplet motion manifests itself in processes as diverse as storm cloud formation, commercial ink-jet printing, petroleum and vegetable oil dehydration, electrospray ionization in mass spectrometry, electrowetting and lab-on-a-chip manipulations. An important issue in practical applications is the tendency for adjacent drops to coalesce, and oppositely charged drops have long been assumed to experience an attractive force that favors their coalescence. Here we report the existence of a critical field strength above which oppositely charged drops do not coalesce. We observe that appropriately positioned and oppositely charged drops migrate towards one another in an applied electric field; but whereas the drops coalesce as expected at low field strengths, they are repelled from one another after contact at higher field strengths. Qualitatively, the drops appear to ``bounce'' off one another. We directly image the transient formation of a meniscus bridge between the bouncing drops, and propose that this temporary bridge is unstable with respect to capillary pressure when it forms in an electric field exceeding a critical strength. The observation of oppositely charged drops bouncing in strong electric fields should affect our understanding of any process involving charged liquid drops, including de-emulsification, electrospray ionization and atmospheric conduction.

  11. Raschig ring HDS catalysts reduce pressure drop

    SciTech Connect

    Moyse, B.

    1984-12-31

    Many hydroprocessing units have a limit on their run length imposed by bed plugging. As opposed to catalyst deactivation, bed plugging can cause pressure drop over the reactor or first reactor in the train to develop rapidly. For this reason many reactor designs call for the use of scale baskets together with grading of topping material and/or catalyst in the top bed of the lead reactor. Nevertheless, many plants have a history of unfavorable pressure drop development. Some refiners must regularly practice catalyst skimming operations. In such pressure drop limiting cases the use of Raschig ring catalysts as part of the reactor fill can markedly improve the pressure drop situation.

  12. Saving every drop of water

    NASA Astrophysics Data System (ADS)

    Jinyu, J.

    2012-04-01

    Since the beginning of 2011 there has been extremely low rainfall, which has resulted in drought conditions that have affected several provinces in China. The situation of the acute water shortage requires people to make many changes in the little things they do in their daily life. Saving every drop of water and forming good habits of using water is of the utmost importance. Based on this need, our students, organized by our teachers, reached out into to the communities. By visiting, observing and issuing questionnaires, the students identified unreasonable water usage in the communities. The results of the research showed that the ratio of secondary treatment of domestic waste is very low, especially the ratio of collecting wastewater from washing, greywater, to flush the toilet. In order to solve this problem, students themselves designed a set of water saving facilities by collecting greywater to flush the toilet. They successfully installed these facilities in residential houses in the XiYinLi community, which achieved satisfactory results regarding saving water.

  13. Accidental Chlorine Gas Intoxication: Evaluation of 39 Patients

    PubMed Central

    Sever, Mustafa; Mordeniz, Cengiz; Sever, Fidan; Dokur, Mehmet

    2009-01-01

    Background Chlorine is a known pulmonary irritant gas that may cause acute damage in the respiratory system. In this paper, the socio-demographic and clinical characteristics of 39 accidentally exposed patients to chlorine gas are reported and different emergency treatment modalities are also discussed. Methods Two emergency departments applications were retrospectively analyzed for evaluation of accidental chlorine gas exposure for year 2007. Patients were classified into 3 groups according to severity of clinical and laboratory findings based on the literature and duration of land of stay in the emergency department. The first group was slightly exposed (discharged within 6 hours), second group moderately exposed (treated and observed for 24 hours), and third group was severely exposed (hospitalized). Most of the patients were initially treated with a combination of humidified oxygen, corticosteroids, and bronchodilators. Results The average age was 17.03 ± 16.01 years (95% CI). Seven (17.9%) of them were female and 29 (74.4%) were children. Twenty-four patients (61.5%) were included in the first, nine (23.1%) were in second and six (15.4%) were in the third group. The presenting symptoms were cough, nausea, and vomiting and conjunctiva hyperemia for the first group, first groups symptoms plus dyspnea for the second group. Second groups symptoms plus palpitation, weakness and chest tightness were for the third group. Cough and dyspnea were seen in 64.1% and 30.8% of the patients respectively. No patients died. Conclusions The authors recommend that non symptomatic or slightly exposed patients do not need any specific treatment or symptomatic treatment is sufficient. Keywords Accidental; Chlorine exposure; Chlorine gas; Chlorine intoxication; Emergency department PMID:22481989

  14. Numerical simulation of industrial and accidental release formation and transport

    SciTech Connect

    Piskunov, V.N.; Aloyan, A.A.; Gerasimov, V.M.; Pinaev, V.S.; Golubev, A.I.; Yanilkin, Yu.V.; Ivanov, N.V.; Nikonov, S.N.; Kharchenko, A.I.

    1995-05-01

    Statement of work for contract 006 {open_quotes}Mathematical simulation of industrial and accidental release formation and transport{close_quotes} implies that the final result of the activity within this task will be VNIIEF developed techniques which will provide for the prediction of the post-accidental environment. Report [1] presents the description of physical models and calculation techniques which were chosen by VNIIEF to accomplish this task. These techniques were analysed for their capabilities, the areas of their application were defined, modifications within contract 006 were described, the results of test and methodical calculations were presented. Moreover, the experimental data were analysed over the source parameters and contamination measurements which can be used in the comparison with the calculation results. Based an these data this report compares the calculation results obtained with VNIIEF calculation techniques with the LANL-presented experimental results. The calculations which statements and results are given in section 1, included the following processes: explosion cloud ascent dynamics and jet release origin; aerosols kinetics in the release source including composite particle origin in the explosion cloud caused by radioactive substance sorption an the soil particles; contaminant transport in atmosphere and their in-site fallout due to the accidental explosions and fires; atmospheric flow dynamics and industrial contamination transfer over the complicated terrain. The calculated results were compared with the experimental data. Section 2 presents the parameters for a typical source in the explosion accidents based an the experimental results and calculated data from Section 1, as well as contamination patterns were calculated with basic technique {open_quotes}Prognosis{close_quotes}.

  15. Evolving practices in environmental scenarios: a new scenario typology

    NASA Astrophysics Data System (ADS)

    Wilkinson, Angela; Eidinow, Esther

    2008-10-01

    A new approach to scenarios focused on environmental concerns, changes and challenges, i.e. so-called 'environmental scenarios', is necessary if global environmental changes are to be more effectively appreciated and addressed through sustained and collaborative action. On the basis of a comparison of previous approaches to global environmental scenarios and a review of existing scenario typologies, we propose a new scenario typology to help guide scenario-based interventions. This typology makes explicit the types of and/or the approaches to knowledge ('the epistemologies') which underpin a scenario approach. Drawing on previous environmental scenario projects, we distinguish and describe two main types in this new typology: 'problem-focused' and 'actor-centric'. This leads in turn to our suggestion for a third type, which we call 'RIMA'—'reflexive interventionist or multi-agent based'. This approach to scenarios emphasizes the importance of the involvement of different epistemologies in a scenario-based process of action learning in the public interest. We suggest that, by combining the epistemologies apparent in the previous two types, this approach can create a more effective bridge between longer-term thinking and more immediate actions. Our description is aimed at scenario practitioners in general, as well as those who work with (environmental) scenarios that address global challenges.

  16. An accidental decapitation resulting from head protruding out of bus.

    PubMed

    Parchake, Manoj Bhausaheb; Tumram, Nilesh K; Umbare, Rahul; Kachare, R V; Dode, C R

    2016-06-01

    Decapitation is the separation of the head from the neck. Accidental decapitation is rare, and very few cases are cited in the literature. In this case, the victim was asleep during an overnight trip with her head sticking out of the window, and she was decapitated by a truck travelling in the opposite direction. Lack of security grilles on windows, high-speed driving, narrow roads and night travel were contributing factors. This case is presented for its rarity and pattern of injuries during the fatal mishap and to consider possible preventive measures. PMID:26857073

  17. Clinical perspectives on osteogenesis imperfecta versus non-accidental injury.

    PubMed

    Pereira, Elaine Maria

    2015-12-01

    Although non-accidental injuries (NAI) are more common in cases of unexplained fractures than rare disorders such as osteogenesis imperfecta (OI), ruling out OI and other medical causes of fracture is always indicated. The majority of OI patients can be diagnosed with the help of family history, physical examination, and radiographic findings. In particular, there are a few radiological findings which are seen more commonly in NAI than in OI which may help guide clinician considerations regarding the probability of either of these diagnoses. At the same time, molecular testing still merits careful consideration in cases with unexplained fractures without obvious additional signs of abuse. 2015 Wiley Periodicals, Inc. PMID:26492946

  18. Method and apparatus for controlling accidental releases of tritium

    DOEpatents

    Galloway, T.R.

    1980-04-01

    An improvement is described in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release. 1 fig.

  19. Method and apparatus for controlling accidental releases of tritium

    DOEpatents

    Galloway, Terry R. [Berkeley, CA

    1980-04-01

    An improvement in a tritium control system based on a catalytic oxidation reactor wherein accidental releases of tritium into room air are controlled by flooding the catalytic oxidation reactor with hydrogen when the tritium concentration in the room air exceeds a specified limit. The sudden flooding with hydrogen heats the catalyst to a high temperature within seconds, thereby greatly increasing the catalytic oxidation rate of tritium to tritiated water vapor. Thus, the catalyst is heated only when needed. In addition to the heating effect, the hydrogen flow also swamps the tritium and further reduces the tritium release.

  20. Self-Administered Ethanol Enema Causing Accidental Death

    PubMed Central

    Peterson, Thomas; Rentmeester, Landen; Judge, Bryan S.; Cohle, Stephen D.; Jones, Jeffrey S.

    2014-01-01

    Excessive ethanol consumption is a leading preventable cause of death in the United States. Much of the harm from ethanol comes from those who engage in excessive or hazardous drinking. Rectal absorption of ethanol bypasses the first pass metabolic effect, allowing for a higher concentration of blood ethanol to occur for a given volume of solution and, consequently, greater potential for central nervous system depression. However, accidental death is extremely rare with rectal administration. This case report describes an individual with klismaphilia whose death resulted from acute ethanol intoxication by rectal absorption of a wine enema. PMID:25436159

  1. The degenerate gravitino scenario

    SciTech Connect

    Boubekeur, Lotfi; Vives, Oscar; Choi, Ki Young; Austri, Roberto Ruiz de E-mail: kiyoung.choi@uam.es E-mail: oscar.vives@uv.es

    2010-04-01

    In this work, we explore the ''degenerate gravitino'' scenario where the mass difference between the gravitino and the lightest MSSM particle is much smaller than the gravitino mass itself. In this case, the energy released in the decay of the next to lightest sypersymmetric particle (NLSP) is reduced. Consequently the cosmological and astrophysical constraints on the gravitino abundance, and hence on the reheating temperature, become softer than in the usual case. On the other hand, such small mass splittings generically imply a much longer lifetime for the NLSP. We find that, in the constrained MSSM (CMSSM), for neutralino LSP or NLSP, reheating temperatures compatible with thermal leptogenesis are reached for small splittings of order 10{sup −2} GeV. While for stau NLSP, temperatures of T{sub RH} ≅ 4 × 10{sup 9}GeV can be obtained even for splittings of order of tens of GeVs. This ''degenerate gravitino'' scenario offers a possible way out to the gravitino problem for thermal leptogenesis in supersymmetric theories.

  2. EXAMPLE EXPOSURE SCENARIOS ASSESSMENT TOOL

    EPA Science Inventory

    Exposure scenarios are a tool to help the assessor develop estimates of exposure, dose, and risk. An exposure scenario generally includes facts, data, assumptions, inferences, and sometimes professional judgment about how the exposure takes place. The human physiological and beh...

  3. Why Do Students Drop Advanced Mathematics?

    ERIC Educational Resources Information Center

    Horn, Ilana

    2004-01-01

    Students, especially black, Latino and Native American youth and students of low socio-economic status drop out of advanced mathematics. Teachers must coordinate their expectations, their knowledge of students and their teaching practices in order to stop struggling students from dropping out of advanced math classes.

  4. 49 CFR 572.102 - Drop test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 7 2012-10-01 2012-10-01 false Drop test. 572.102 Section 572.102 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Free Motion Headform § 572.102 Drop test. (a) When the headform is...

  5. University Drop-Out: An Italian Experience

    ERIC Educational Resources Information Center

    Belloc, Filippo; Maruotti, Antonello; Petrella, Lea

    2010-01-01

    University students' drop-out is a crucial issue for the universities' efficiency evaluation and funding. In this paper, we analyze the drop-out rate of the Economics and Business faculty of Sapienza University of Rome. We use administrative data on 9,725 undergraduates students enrolled in three-years bachelor programs from 2001 to 2007 and…

  6. Drop tower with no aerodynamic drag

    NASA Technical Reports Server (NTRS)

    Kendall, J. M., Jr.

    1981-01-01

    Cooling air accelerated to match velocity of falling object eliminates drag. 3 meter drop tower with suction fan and specific geometry causes air to accelerate downward at 1 g. Although cooling of molten material released from top is slow because surrounding air moves with it, drop remains nearly spherical.

  7. Drop test facility available to private industry

    SciTech Connect

    Shappert, L.B.; Box, W.D.

    1983-01-01

    In 1978, a virtually unyielding drop test impact pad was constructed at Oak Ridge National Laboratory's (ORNL's) Tower Shielding Facility (TSF) for the testing of heavy shipping containers designed for transporting radioactive materials. Because of the facility's unique capability for drop-testing large, massive shipping packages, it has been identified as a facility which can be made available for non-DOE users.

  8. 49 CFR 178.965 - Drop test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Large Packaging design types and performed periodically as specified in § 178.955(e) of this subpart. (b... of 0.45 cubic meters (15.9 cubic feet) or less must be subject to an additional drop test. (e) Drop... must be those specified in paragraph (e)(1) of this section for each Large Packaging design type;...

  9. 49 CFR 178.810 - Drop test.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of all IBC design types must be dropped onto a rigid, non-resilient, smooth, flat and horizontal... design types and performed periodically as specified in § 178.801(e) of this subpart. (b) Special.... Following the drop, the IBC must be restored to the upright position for observation. (2) IBC design...

  10. Experimental validation of a numerical model for predicting the trajectory of blood drops in typical crime scene conditions, including droplet deformation and breakup, with a study of the effect of indoor air currents and wind on typical spatter drop trajectories.

    PubMed

    Kabaliuk, N; Jermy, M C; Williams, E; Laber, T L; Taylor, M C

    2014-10-18

    Bloodstain Pattern Analysis (BPA) provides information about events during an assault, e.g. location of participants, weapon type and number of blows. To extract the maximum information from spatter stains, the size, velocity and direction of the drop that produces each stain, and forces acting during flight, must be known. A numerical scheme for accurate modeling of blood drop flight, in typical crime scene conditions, including droplet oscillation, deformation and in-flight disintegration, was developed and validated against analytical and experimental data including passive blood drop oscillations, deformation at terminal velocity, cast-off and impact drop deformation and breakup features. 4th order Runge-Kutta timestepping was used with the Taylor Analogy Breakup (TAB) model and Pilch and Erdman's (1987) expression for breakup time. Experimental data for terminal velocities, oscillations, and deformation was obtained via digital high-speed imaging. A single model was found to describe drop behavior accurately in passive, cast off and impact scenarios. Terminal velocities of typical passive drops falling up to 8m, distances and times required to reach them were predicted within 5%. Initial oscillations of passive blood drops with diameters of 1mmdrop aspect ratio were within 1.6% of experiment. Under typical crime scene conditions, the velocity of the drop within the first 1.5m of fall is affected little by drag, oscillation or deformation. Blood drops with diameter 0.4-4mm and velocity 1-15m/s cast-off from a rotating disk showed low deformation levels (Weber number<3). Drops formed by blunt impact 0.1-2mm in diameter at velocities of 14-25m/s were highly deformed (aspect ratios down to 0.4) and the larger impact blood drops (∼1-1.5mm in diameter) broke up at critical Weber numbers of 12-14. Most break-ups occurred within 10-20cm of the impact point. The model predicted deformation levels of cast-off and impact blood drops within 5% of experiment. Under typical crime scene conditions, few cast-off drops will break up in flight. However some impact-generated drops were seen to break up, some by the vibration, others by bag breakup. The validated model can be used to gain deep understanding of the processes leading to spatter stains, and can be used to answer questions about proposed scenarios, e.g. how far blood drops may travel, or how stain patterns are affected by winds and draughts. PMID:25447183

  11. Planar microfluidic drop splitting and merging.

    PubMed

    Collignon, Sean; Friend, James; Yeo, Leslie

    2015-04-21

    Open droplet microfluidic platforms offer attractive alternatives to closed microchannel devices, including lower fabrication cost and complexity, significantly smaller sample and reagent volumes, reduced surface contact and adsorption, as well as drop scalability, reconfigurability, and individual addressability. For these platforms to be effective, however, they require efficient schemes for planar drop transport and manipulation. While there are many methods that have been reported for drop transport, it is far more difficult to carry out other drop operations such as dispensing, merging and splitting. In this work, we introduce a novel alternative to merge and, more crucially, split drops using laterally-offset modulated surface acoustic waves (SAWs). The energy delivery into the drop is divided into two components: a small modulation amplitude excitation to initiate weak rotational flow within the drop followed by a short burst in energy to induce it to stretch. Upon removal of the SAW energy, capillary forces at the center of the elongated drop cause the liquid in this capillary bridge region to drain towards both ends of the drop, resulting in its collapse and therefore the splitting of the drop. This however occurs only below a critical Ohnesorge number, which is a balance between the viscous forces that retard the drainage and the sufficiently large capillary forces that cause the liquid bridge to pinch. We show the possibility of reliably splitting drops into two equal sized droplets with an average deviation in their volumes of only around 4% and no greater than 10%, which is comparable to the 7% and below splitting deviation obtained with electrowetting drop splitting techniques. In addition, we also show that it is possible to split the drop asymmetrically to controllably and reliably produce droplets of different volumes. Such potential as well as the flexibility in tuning the device to operate on drops of different sizes without requiring electrode reconfiguration, i.e., the use of different devices, as is required in electrowetting-therefore makes the present method an attractive alternative to electrowetting schemes. PMID:25738425

  12. CPAS Preflight Drop Test Analysis Process

    NASA Technical Reports Server (NTRS)

    Englert, Megan E.; Bledsoe, Kristin J.; Romero, Leah M.

    2015-01-01

    Throughout the Capsule Parachute Assembly System (CPAS) drop test program, the CPAS Analysis Team has developed a simulation and analysis process to support drop test planning and execution. This process includes multiple phases focused on developing test simulations and communicating results to all groups involved in the drop test. CPAS Engineering Development Unit (EDU) series drop test planning begins with the development of a basic operational concept for each test. Trajectory simulation tools include the Flight Analysis and Simulation Tool (FAST) for single bodies, and the Automatic Dynamic Analysis of Mechanical Systems (ADAMS) simulation for the mated vehicle. Results are communicated to the team at the Test Configuration Review (TCR) and Test Readiness Review (TRR), as well as at Analysis Integrated Product Team (IPT) meetings in earlier and intermediate phases of the pre-test planning. The ability to plan and communicate efficiently with rapidly changing objectives and tight schedule constraints is a necessity for safe and successful drop tests.

  13. Biomass Scenario Model Scenario Library: Definitions, Construction, and Description

    SciTech Connect

    Inman, D.; Vimmerstedt, L.; Bush, B.; Peterson, S.

    2014-04-01

    Understanding the development of the biofuels industry in the United States is important to policymakers and industry. The Biomass Scenario Model (BSM) is a system dynamics model of the biomass-to-biofuels system that can be used to explore policy effects on biofuels development. Because of the complexity of the model, as well as the wide range of possible future conditions that affect biofuels industry development, we have not developed a single reference case but instead developed a set of specific scenarios that provide various contexts for our analyses. The purpose of this report is to describe the scenarios that comprise the BSM scenario library. At present, we have the following policy-focused scenarios in our library: minimal policies, ethanol-focused policies, equal access to policies, output-focused policies, technological diversity focused, and the point-of-production- focused. This report describes each scenario, its policy settings, and general insights gained through use of the scenarios in analytic studies.

  14. Intercomparison of oil spill prediction models for accidental blowout scenarios with and without subsea chemical dispersant injection.

    PubMed

    Socolofsky, Scott A; Adams, E Eric; Boufadel, Michel C; Aman, Zachary M; Johansen, Øistein; Konkel, Wolfgang J; Lindo, David; Madsen, Mads N; North, Elizabeth W; Paris, Claire B; Rasmussen, Dorte; Reed, Mark; Rønningen, Petter; Sim, Lawrence H; Uhrenholdt, Thomas; Anderson, Karl G; Cooper, Cortis; Nedwed, Tim J

    2015-07-15

    We compare oil spill model predictions for a prototype subsea blowout with and without subsea injection of chemical dispersants in deep and shallow water, for high and low gas-oil ratio, and in weak to strong crossflows. Model results are compared for initial oil droplet size distribution, the nearfield plume, and the farfield Lagrangian particle tracking stage of hydrocarbon transport. For the conditions tested (a blowout with oil flow rate of 20,000 bbl/d, about 1/3 of the Deepwater Horizon), the models predict the volume median droplet diameter at the source to range from 0.3 to 6mm without dispersant and 0.01 to 0.8 mm with dispersant. This reduced droplet size owing to reduced interfacial tension results in a one to two order of magnitude increase in the downstream displacement of the initial oil surfacing zone and may lead to a significant fraction of the spilled oil not reaching the sea surface. PMID:26021288

  15. Atmospheric entry of Mars-return nuclear-powered vehicles due to accidental termination of operations

    NASA Technical Reports Server (NTRS)

    Menees, Gene P.; Park, Chul

    1993-01-01

    The entry of nuclear reactors into Earth's atmosphere resulting from an accidental or inadvertent abort of a space vehicle powered by nuclear-thermal rockets is investigated. The study is made for a typical piloted Mars mission vehicle incapacitated by an accident or malfunction during the Earth-arrival phase of the Mars-return journey due to simultaneous, multiple failures of its component systems. A single accident/abort scenario resulting in three entry possibilities is considered for a nominal hyperbolic in-bound approach velocity of 8 km/sec. The most severe case involving a direct entry is then analyzed over a broad range of approach velocities extending to 12 km/sec to include sprint-type missions. The results indicate that the severe surface heating, stagnation pressures, and g-loads are greater than 150 kW/sq cm, 300 atm, and 800-g, respectively. The wall heat transfer rate exceeds the value that can be accommodated by a carbon heatshield through radiation equilibrium prior to sublimation at 5500 K. These conditions are beyond our previous experience in crew safety, structural design, and thermal protection.

  16. Atmospheric entry of Mars-return nuclear-powered vehicles due to accidental termination of operations

    NASA Astrophysics Data System (ADS)

    Menees, Gene P.; Park, Chul

    1993-06-01

    The entry of nuclear reactors into Earth's atmosphere resulting from an accidental or inadvertent abort of a space vehicle powered by nuclear-thermal rockets is investigated. The study is made for a typical piloted Mars mission vehicle incapacitated by an accident or malfunction during the Earth-arrival phase of the Mars-return journey due to simultaneous, multiple failures of its component systems. A single accident/abort scenario resulting in three entry possibilities is considered for a nominal hyperbolic in-bound approach velocity of 8 km/sec. The most severe case involving a direct entry is then analyzed over a broad range of approach velocities extending to 12 km/sec to include sprint-type missions. The results indicate that the severe surface heating, stagnation pressures, and g-loads are greater than 150 kW/sq cm, 300 atm, and 800-g, respectively. The wall heat transfer rate exceeds the value that can be accommodated by a carbon heatshield through radiation equilibrium prior to sublimation at 5500 K. These conditions are beyond our previous experience in crew safety, structural design, and thermal protection.

  17. Supercooled water drops impacting superhydrophobic textures.

    PubMed

    Maitra, Tanmoy; Antonini, Carlo; Tiwari, Manish K; Mularczyk, Adrian; Imeri, Zulkufli; Schoch, Philippe; Poulikakos, Dimos

    2014-09-16

    Understanding the interaction of supercooled metastable water with superhydrophobic surface textures is of fundamental significance for unraveling the mechanisms of icing as well as of practical importance for the rational development of surface treatment strategies to prevent icing. We investigate the problem of supercooled water drops impacting superhydrophobic textures for drop supercooling down to -17 °C and find that increased viscous effects significantly influence all stages of impact dynamics, in particular, the impact and meniscus impalement behavior, with severe implications to water retention by the textures (sticky versus rebounding drop) and possible icing. Viscous effects in water supercooling conditions cause a reduction of drop maximum spreading (∼25% at an impact speed of 3 m/s for a millimetric drop) and can significantly decrease the drop recoil speed when the meniscus partially penetrates into the texture, leading to an increase of the contact time up to a factor of 2 in supercooling conditions compared to room temperature. We also show that meniscus penetration upon drop impact occurs with full penetration at the center, instead of ring shape, common to room temperature drop impact. To this end, we describe an unobserved mechanism for superhydrophobicity breakdown: unlike for room temperature drops, where transition from bouncing to sticky (impaled) behavior occurs sharply at the condition of full texture penetration, with a bubble captured at the point of impact, under supercooled conditions, the full penetration velocity threshold is increased markedly (increasing by ∼25%, from 2.8 to 3.5 m/s) and no bubble is entrapped. However, even though only partial texture penetration takes place, failure to completely dewet because of viscous effects can still prohibit complete supercooled drop rebound. PMID:25157476

  18. On the Stability of Rotating Drops.

    PubMed

    Nurse, A K; Coriell, S R; McFadden, G B

    2015-01-01

    We consider the equilibrium and stability of rotating axisymmetric fluid drops by appealing to a variational principle that characterizes the equilibria as stationary states of a functional containing surface energy and rotational energy contributions, augmented by a volume constraint. The linear stability of a drop is determined by solving the eigenvalue problem associated with the second variation of the energy functional. We compute equilibria corresponding to both oblate and prolate shapes, as well as toroidal shapes, and track their evolution with rotation rate. The stability results are obtained for two cases: (i) a prescribed rotational rate of the system ("driven drops"), or (ii) a prescribed angular momentum ("isolated drops"). For families of axisymmetric drops instabilities may occur for either axisymmetric or non-axisymmetric perturbations; the latter correspond to bifurcation points where non-axisymmetric shapes are possible. We employ an angle-arc length formulation of the problem which allows the computation of equilibrium shapes that are not single-valued in spherical coordinates. We are able to illustrate the transition from spheroidal drops with a strong indentation on the rotation axis to toroidal drops that do not extend to the rotation axis. Toroidal drops with a large aspect ratio (major radius to minor radius) are subject to azimuthal instabilities with higher mode numbers that are analogous to the Rayleigh instability of a cylindrical interface. Prolate spheroidal shapes occur if a drop of lower density rotates within a denser medium; these drops appear to be linearly stable. This work is motivated by recent investigations of toroidal tissue clusters that are observed to climb conical obstacles after self-assembly [Nurse et al., Journal of Applied Mechanics 79 (2012) 051013]. PMID:26958440

  19. Preventing Accidental Ignition of Upper-Stage Rocket Motors

    NASA Technical Reports Server (NTRS)

    Hickman, John; Morgan, Herbert; Cooper, Michael; Murbach, Marcus

    2005-01-01

    A report presents a proposal to reduce the risk of accidental ignition of certain upper-stage rocket motors or other high energy hazardous systems. At present, mechanically in-line initiators are used for initiation of many rocket motors and/or other high-energy hazardous systems. Electrical shorts and/or mechanical barriers, which are the basic safety devices in such systems, are typically removed as part of final arming or pad preparations while personnel are present. At this time, static discharge, test equipment malfunction, or incorrect arming techniques can cause premature firing. The proposal calls for a modular out-of-line ignition system incorporating detonating-cord elements, identified as the donor and the acceptor, separated by an air gap. In the safe configuration, the gap would be sealed with two shields, which would prevent an accidental firing of the donor from igniting the system. The shields would be removed to enable normal firing, in which shrapnel generated by the donor would reliably ignite the acceptor to continue the ordnance train. The acceptor would then ignite a through bulkhead initiator (or other similar device), which would ignite the motor or high-energy system. One shield would be remotely operated and would be moved to the armed position when a launch was imminent or conversely returned to the safe position if the launch were postponed. In the event of failure of the remotely operated shield, the other shield could be inserted manually to safe the system.

  20. Accidental childhood death and the role of the pathologist.

    PubMed

    Byard, R W

    2000-01-01

    The following study provides an overview of accidental childhood death. This study is based on a review of 369 cases of fatal childhood accidents taken from the records of the Department of Histopathology, Women's and Children's Hospital, Adelaide, Australia, over a 34-year period from 1963 to 1996. Data provide information on deaths due to motor vehicle accidents, drownings, accidental asphyxia, burns, poisonings, electrocution, and miscellaneous trauma. In addition, certain categories have undergone further examination, including asphyxial deaths due to unsafe sleeping environments and unsafe eating practices, drowning deaths, and deaths on farms, following identification of significant child safety problems in these areas as part of the "Keeping Your Baby and Child Safe" program. Previously unrecognized dangers to children detected through this program include mesh-sided cots, V-shaped pillows, and certain types of stroller-prams. The production of information pamphlets and packages for parents and the recall of certain dangerous products following recommendations made by pathologists demonstrate that pediatric and forensic pathologists have an important role to play in preventive medicine issues and in formulating public health strategies. PMID:10890925

  1. [Accidental extubation in a pediatric intensive care unit].

    PubMed

    Piva, J P; Amantéa, S; Luchese, S; Giugno, K; Maia, T R; Einloft, L

    1995-01-01

    It is an on-going practice in the pediatric ICUs to obtain and to maintain a working artificial airway. Nevertheless this procedure bears not infrequent risks of accidental extubation (AE) which ranges in several services from 0.9 to 3.3 for each 100 days of intubation. The risk factors that are involved in AE are related to: sedation level, age-group, intubation path, and others. The purpose of the authors in this article was to observe the incidence of AE in their service and to compare the relative risk in the rate of AE among orotracheal and nasotracheal intubation population. A prospective study was taken during six months, in which every patients with artificial airway admitted at the PICU of the Santo Antonio Hospital in Porto Alegre (Brazil) was included except those with tracheostomy. The total number of cases were 673 patients-day with artificial airway, with an average of 3.7 patients with tracheal tube per day. In the period there were 18 AE, with a rate of 2.7 AE/ 100 days. The incidence rate of AE in the orotracheal group was 3.1% and 1.6% in the nasotracheal group with no statistically significant difference (p=0.6). The authors concluded that the pathway of intubation in their study does not carry any additional risk in the incidence of accidental extubation. PMID:14689021

  2. Forensic aspects of 40 accidental autoerotic deaths in Northern Germany.

    PubMed

    Janssen, W; Koops, E; Anders, S; Kuhn, S; Pschel, K

    2005-01-17

    Between 1983 and 2003, 40 accidental autoerotic fatalities have been investigated. in the Institute of Legal Medicine in Hamburg. Only 50% (n=20) were autopsied (13 legal autopsies, 6 for scientific purposes and 1 for an insurance company). All the victims were males, aged between 13 and 79 years (among them five children and adolescents, the deceased mainly between 20 and 40 years). The paraphiliacs utilized a great range of devices and props as fetishism, sexual aids or pain-stimulating agents, like intimate feminine garments, ropes, chains, bondages, locks, pornographic magazines, condoms, rubber items, and chemical anaesthetics. The cause of death was strangulation in 20 cases (17 x hanging, 3 x ligature strangulation), 11 x suffocation (8 x under plastic bags, 3 x with face-masks, 2 x thoracic compression, 1 x positional asphyxia, and 1 x cocaine intoxication). Five cases without autopsy remained unclear because of missing morphological and toxicological findings; it could not be differentiated between asphyxiation/intoxication/natural disease, although the scene characteristics seemed to be typical for autoerotic deaths. It is emphasized that the findings at the scene, the morphological and toxicological examination of the dead body (full autopsy as prerequisite) by experienced investigators and the personal history of the deceased have to be evaluated very carefully and intensely to reconstruct the accidental fatal autoerotic course accurately and undoubtedly (to exclude the possibility of sexual homicide, neglected killing, or suicide). PMID:15694733

  3. Fatal accidental asphyxia in a jack-knife position.

    PubMed

    Benomran, F A

    2010-10-01

    Accidental death from postural or positional asphyxia takes place when the abnormal position of the victim's body compromises the process of respiration. Diagnosis is largely made by circumstantial evidence supported by absence of any other significant pathology or trauma explaining death. This case report is about a 50-year-old male who had been drinking the previous night and was found dead in the morning inside a tire repair shop. His jack-knifed body had been encompassed, buttocks-down, within the hollow core made by 3 big tires stacked on top of each other. The author was called to the scene of death and had hands-on encounter with the body in-situ where scene photographs were taken. Apart from a blood alcohol of 290 mg/100 ml, marked congestion of the face, petechial hemorrhages on the conjunctivae and lung edema and congestion, autopsy findings were unremarkable. Abrasions on shoulders, lateral aspects of arms and posterior aspects of lower legs indicated friction with internal rims of tires while slipping down. There were no other injuries or pathology to account for his death. Death was determined to be due to accidental postural asphyxia secondary to intoxication by alcohol. PMID:20851361

  4. Multidisciplinary approach to "accidental" falls in the elderly: a case report.

    PubMed

    Galizia, Gianluigi; Testa, Gianluca; Mazzella, Francesca; Cacciatore, Francesco; Ungar, Andrea; Masotti, Giulio; Rengo, Franco; Abete, Pasquale

    2008-06-01

    Falls in the elderly are commonly and often wrongly identified as "accidental". We report a case of an elderly woman admitted to first aid for a trauma due to an accidental fall. Geriatric multidisciplinary evaluation revealed mild cognitive impairment associated with depressive symptoms; both findings made the anamnesis uncertain. Syncope algorithm was applied and "tachy-brady form of sick sinus syndrome" was diagnosed. Differential diagnosis between "accidental" and "apparently accidental" falls in elderly patients is very difficult but a multidisciplinary geriatric evaluation can clarify the correct diagnosis. PMID:18713166

  5. Pattern formation in evaporating drops

    NASA Astrophysics Data System (ADS)

    Li, Fang-I.

    The redistribution of organic solutes during drop evaporation is a nanoscale self assembly process with relevance to technologies ranging from inkjet printing of organic displays to synthesis of bio-smart interfaces for sensing and screening. Atomic force microscopy studies comparing the behavior of different generation dendrimers with different surface chemistry in two solvent alcohols on mica substrates confirm that the detailed morphologies of condensed dendrimer ring structures resulting from micro-droplet evaporation sensitively depend on the surface chemistry, the solute evaporation rate and the dendrimer generation. For the dilute concentration studied here the presence of periodically 'scalloped' molecular rings is ubiquitous. The instability wavelength of the scalloped rings is found to be proportional to the width of the ring, similar to observations of the rim instability in dewetting holes. The effect of the surface chemistry of the dendrimer molecules is obvious in the detailed structure of the self assembled rings. Varying the chain length of solvent alcohol leads to modification of ring patterns. The influence of dendrimer generation on ring structure primarily reflects the increase in dendrimer density with generation number. The evolution of G2-50%C12 -pentanol rings as a function of dendrimer concentration is also described. High surface mobility and phase transformation phenomena in condensed, micro-scale dendrimer structures are documented, again using atomic force microscopy. Stratified dendrimer rings undergo dramatic temperature, time and dendrimer generation dependent morphological changes associated with large-scale molecular rearrangements and partial melting. These transformations produce ring structures consisting of a highly stable first monolayer of the scalloped structure in equilibrium with spherical cap shaped dendrimer islands that form at the center of each pre-existing scallop (creating a 'pearl necklace' structure). Analysis of the dendrimer island shapes reveals a dependence of island contact angle on contact line curvature (island size) that varies systematically with dendrimer generation. The morphological transformations in this system indicate the potential for creating complex, dendrimer-based multilevel structures and macroscopic scale arrays using, for example, droplet-on-demand or dip pen nanolithography techniques, coupled with appropriate annealing and stabilizing treatments.

  6. Scenario planning and nanotechnological futures

    NASA Astrophysics Data System (ADS)

    Farber, Darryl; Lakhtakia, Akhlesh

    2009-07-01

    Scenario planning may assist us in harnessing the benefits of nanotechnology and managing the associated risks for the good of the society. Scenario planning is a way to describe the present state of the world and develop several hypotheses about the future of the world, thereby enabling discussions about how the world ought to be. Scenario planning thus is not only a tool for learning and foresight, but also for leadership. Informed decision making by experts and political leaders becomes possible, while simultaneously allaying the public's perception of the risks of new and emerging technologies such as nanotechnology. Two scenarios of the societal impact of nanotechnology are the mixed-signals scenario and the confluence scenario. Technoscientists have major roles to play in both scenarios.

  7. The Drop Tower Bremen -An Overview

    NASA Astrophysics Data System (ADS)

    von Kampen, Peter; Könemann, Thorben; Rath, Hans J.

    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University of Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of ZARM`s drop tower began. Since its inau-guration in September 1990, the eye-catching Drop Tower Bremen with a height of 146m and its characteristic glass roof has become twice a landmark on the campus of the University of Bremen and the emblem of the technology park Bremen. As such an outstanding symbol of space science in Bremen the drop tower provides an european unique facility for experiments under conditions of high-quality weightlessness with residual gravitational accelerations in the microgravity regime. The period of maximum 4.74s of each freely falling experiment at the Drop Tower Bremen is only limited by the height of the drop tower vacuum tube, which was fully manufactured of steal and enclosed by an outer concrete shell. Thus, the pure free fall height of each microgravity drop experiment is approximately 110m. By using the later in-stalled catapult system established in 2004 ZARM`s short-term microgravity laboratory is able to nearly double the time of free fall. This world-wide inimitable capsule catapult system meets scientists` demand of extending the period of weightlessness. During the catapult operation the experiment capsule performs a vertical parabolic flight within the drop tower vacuum tube. In this way the time of microgravity can be extended to slightly over 9s. Either in the drop or in the catapult operation routine the repetition rates of microgravity experiments at ZARM`s drop tower facility are the same, generally up to 3 times per day. In comparison to orbital platforms the ground-based laboratory Drop Tower Bremen represents an economic alternative with a permanent access to weightlessness on earth. Moreover, the exceptional high quality of weightlessness in order of 1e-6 g (in the frequency range below 100Hz) demonstrates a perfect experimental environment for unperturbed investigations of scientific phenomena. Motivated by these prospects many national and international groups have initialized research programs taking advantage of this drop tower facility. In respect thereof the spectrum of research fields and technologies in space-related conditions can be continuously enhanced at ZARM. In the first of our two talks we will give you an overview about the inner structure of ZARM, as well as the service and the operation offered by the ZARM Drop Tower Operation and Service Company (ZARM FAB mbH). The ZARM FAB mbH owned by the State Government of Bremen is a public company maintaining the drop tower facility and supporting experimentalists in scientific and technical questions before, during and after their drop or catapult campaigns. In detail, we will present you important technical drop tower informations, our support and the idea, how you can proceed with your microgravity-related experiment including all your requirements to successfully accomplish an entire drop or catapult campaign. In summary, we will illustrate the complete procedure, how to drop or to catapult an experiment capsule at the Drop Tower Bremen.

  8. Drops and emulsions with complex interfaces

    NASA Astrophysics Data System (ADS)

    Erni, Philipp; Windhab, Erich J.; Fischer, Peter

    2007-11-01

    We study the behavior of emulsion drops in external flow fields, focusing on recent experimental work involving liquid interfaces covered with surface-active species, in particular adsorbed proteins and particles. Three different length scales are considered: (i) the rheology of complex interfaces is discussed for adsorbed polyelectrolyte surfactants with different molecular structure (compact and globular vs. random coil); (ii) the flow of single drops with macromolecular adsorption layers is studied in optical flow cells; (iii) dilute emulsions of drops are investigated using rheo-small angle light scattering (rheo-SALS). We discuss the results in the context of emulsion and drop models accounting for interfacial viscoelasticity, as well as with capsule suspension models for the case of rigid interfacial layers. Drops stabilized by adsorbed particles or globular proteins can be understood as capsules surrounded by a soft shell; their behavior on the single drop level is in many ways reminiscent of phenomena observed with red blood cells or vesicles, including non-linear drop shape fluctuations under creeping flow conditions. References: [1] Fischer P, Erni P. Curr Opin Colloid Interface Sci (2007, accepted) [2] Erni P et al., Appl Phys Lett 87, 244104 (2007)

  9. Microjetting from wave focusing on oscillating drops

    NASA Astrophysics Data System (ADS)

    Thoroddsen, S. T.; Etoh, T. G.; Takehara, K.

    2007-05-01

    We present experimental observations of microjetting from an oscillating drop. The jet is generated by the focusing of axisymmetric capillary waves that overturn and collide at an apex of the drop. These jets are up to two orders of magnitude smaller than the original drops. We present two widely different configurations that produce such microjets. The first occurs on a satellite drop, produced by the pinch-off of a water drop from a vertical nozzle. The large oscillations following the contraction of the satellite bridge focus waves at the bottom, sending out a 30μm jet at 9.9m/s. The second jet arises when a water drop, containing surfactants, falls onto and passes through a hemispherical soap film. The gentle deformation of the drop creates a surface wave that focuses at its top, shooting out a tiny jet and entrapping a small bubble inside the drop. This jet is 16±5μm in diameter and emerges at 6.3m/s. In this configuration, the soap film wraps around the drop and acts as a sensor of the air flow, revealing that the liquid jet is preceded by a localized faster-moving air jet. The jetting in both configurations is quite robust and occurs even for slightly asymmetric conditions. These microjets appear for much lower values of the Reynolds and Weber numbers than previously observed, suggesting that free-surface jetting is not limited to the inviscid capillary-inertial regime, which has been the focus of much of the theoretical work.

  10. Rotation of ultrasonically levitated glycerol drops

    NASA Technical Reports Server (NTRS)

    Biswas, A.; Leung, E. W.; Trinh, E. H.

    1991-01-01

    Ultrasonic levitation is used to suspend single millimeter-size glycerol drops in a rectangular chamber. Audio-frequency laterally standing waves set up in the chamber are used to torque the suspended drops. The shape evolution of the drop under the combined effect of centrifugal forces and the acoustic radiation stress, along with its angular velocity are monitored, using video imaging and light scattering techniques. The results show good qualitative agreement with the theoretically predicted shape evolution as a function of angular velocity.

  11. On the Deepwater Horizon drop size distributions

    NASA Astrophysics Data System (ADS)

    Ryerson, T. B.; Atlas, E. L.; Blake, D. R.; De Gouw, J. A.; Warneke, C.; Peischl, J.; Brock, C. A.; McKeen, S. A.

    2014-12-01

    Model simulations of the fate of gas and oil released following the Deepwater Horizon blowout in 2012 depend critically on the assumed drop size distributions. We use direct observations of surfacing time, surfacing location, and atmospheric chemical composition to infer an average drop size distribution for June 10, 2012, providing robust first-order constraints on parameterizations in models. We compare the inferred drop size distribution to published work on Deepwater Horizon and discuss the ability of this approach to determine the efficacy of subsurface dispersant injection.

  12. Nanofluid Drop Evaporation: Experiment, Theory, and Modeling

    NASA Astrophysics Data System (ADS)

    Gerken, William James

    Nanofluids, stable colloidal suspensions of nanoparticles in a base fluid, have potential applications in the heat transfer, combustion and propulsion, manufacturing, and medical fields. Experiments were conducted to determine the evaporation rate of room temperature, millimeter-sized pendant drops of ethanol laden with varying amounts (0-3% by weight) of 40-60 nm aluminum nanoparticles (nAl). Time-resolved high-resolution drop images were collected for the determination of early-time evaporation rate (D2/D 02 > 0.75), shown to exhibit D-square law behavior, and surface tension. Results show an asymptotic decrease in pendant drop evaporation rate with increasing nAl loading. The evaporation rate decreases by approximately 15% at around 1% to 3% nAl loading relative to the evaporation rate of pure ethanol. Surface tension was observed to be unaffected by nAl loading up to 3% by weight. A model was developed to describe the evaporation of the nanofluid pendant drops based on D-square law analysis for the gas domain and a description of the reduction in liquid fraction available for evaporation due to nanoparticle agglomerate packing near the evaporating drop surface. Model predictions are in relatively good agreement with experiment, within a few percent of measured nanofluid pendant drop evaporation rate. The evaporation of pinned nanofluid sessile drops was also considered via modeling. It was found that the same mechanism for nanofluid evaporation rate reduction used to explain pendant drops could be used for sessile drops. That mechanism is a reduction in evaporation rate due to a reduction in available ethanol for evaporation at the drop surface caused by the packing of nanoparticle agglomerates near the drop surface. Comparisons of the present modeling predictions with sessile drop evaporation rate measurements reported for nAl/ethanol nanofluids by Sefiane and Bennacer [11] are in fairly good agreement. Portions of this abstract previously appeared as: W. J. Gerken, A. V. Thomas, N. Koratkar and M. A. Oehlschlaeger, Int. J. Heat Mass Transfer, vol. 74, no. 1, pp. 263-268, July 2014. W. J. Gerken, M. A. Oehlschlaeger, "Nanofluid Pendant Droplet Evaporation", in Proceedings of the ASME 2013 Summer Heat Transfer Conference, Minneapolis, MN, 2013, pp. V001T03A018.

  13. Condensation-induced jumping water drops

    NASA Astrophysics Data System (ADS)

    Narhe, R. D.; Khandkar, M. D.; Shelke, P. B.; Limaye, A. V.; Beysens, D. A.

    2009-09-01

    Water droplets can jump during vapor condensation on solid benzene near its melting point. This phenomenon, which can be viewed as a kind of micro scale steam engine, is studied experimentally and numerically. The latent heat of condensation transferred at the drop three phase contact line melts the substrate during a time proportional to R (the drop radius). The wetting conditions change and a spontaneous jump of the drop results in random direction over length ˜1.5R , a phenomenon that increases the coalescence events and accelerates the growth. Once properly rescaled by the jump length scale, the growth dynamics is, however, similar to that on a solid surface.

  14. Condensation-induced jumping water drops.

    PubMed

    Narhe, R D; Khandkar, M D; Shelke, P B; Limaye, A V; Beysens, D A

    2009-09-01

    Water droplets can jump during vapor condensation on solid benzene near its melting point. This phenomenon, which can be viewed as a kind of micro scale steam engine, is studied experimentally and numerically. The latent heat of condensation transferred at the drop three phase contact line melts the substrate during a time proportional to R (the drop radius). The wetting conditions change and a spontaneous jump of the drop results in random direction over length approximately 1.5R , a phenomenon that increases the coalescence events and accelerates the growth. Once properly rescaled by the jump length scale, the growth dynamics is, however, similar to that on a solid surface. PMID:19905120

  15. Accidental death of elderly persons under the influence of chlorpheniramine.

    PubMed

    Suzuki, Hideto; Shigeta, Akio; Fukunaga, Tatsushige

    2013-09-01

    Older individuals are susceptible to accident, such as falls, some of which are fatal. In such cases, autopsies and toxicological analysis may be deemed unnecessary, especially if the critical injuries and manner of death can be determined conclusively based on information at the scene and an external investigation. Here, we report the results of two autopsies performed on elderly individuals who died accidentally under the influence of chlorpheniramine. These autopsies revealed valuable additional information. Case 1: A woman in her 70s, who was living alone, was found dead under the stairs in her house. She had no history of a condition that could have led to sudden death. The autopsy revealed a neck fracture, multiple rib fractures, and a coccyx fracture. The histopathological findings showed fat embolisms in numerous small vessels of the interalveolar septum. Toxicological analysis of blood samples revealed the presence of chlorpheniramine (0.41μg/ml). Case 2: A woman in her 70s, who was living alone, was found dead in the bathtub in her house. There was no past medical history other than diabetes mellitus and vertigo. The autopsy revealed hyper-inflated lungs and brown-red fluids in the trachea, but there was no evidence of a pathology or injury that could have induced a loss of consciousness. Toxicological analysis of the fluids in the right thoracic cavity revealed the presence of chlorpheniramine (0.57μg/ml). In both cases, re-examination of the scene after the autopsy revealed the presence of common cold medicine containing chlorpheniramine. The victim may have accidentally overdosed on common cold medicine. This overdose would have been compounded by anti-histamine-induced drowsiness. The present cases suggest that forensic pathologists should always notify physicians/pharmacists of findings pertaining to unexpected drug side effects. Such intervention would prevent many accidental deaths. In addition, each autopsy must be performed in conjunction with a detailed postmortem investigation. Such efforts would also increase the accuracy of the public health record's mortality statistics. PMID:23747192

  16. Mission Scenario Development Workbench

    NASA Technical Reports Server (NTRS)

    Kordon, Mark; Baker, John; Gilbert, John; Hanks, David; Mandutianu, Dan; Hooper, David

    2006-01-01

    The Mission Scenario Development Workbench (MSDW) is a multidisciplinary performance analysis software tool for planning and optimizing space missions. It provides a number of new capabilities that are particularly useful for planning the surface activities on other planets. MSDW enables rapid planning of a space mission and supports flight system and scientific-instrumentation trades. It also provides an estimate of the ability of flight, ground, and science systems to meet high-level mission goals and provides means of evaluating expected mission performance at an early stage of planning in the project life cycle. In MSDW, activity plans and equipment-list spreadsheets are integrated with validated parameterized simulation models of spacecraft systems. In contrast to traditional approaches involving worst-case estimates with large margins, the approach embodied in MSDW affords more flexibility and more credible results early in the lifecycle through the use of validated, variable- fidelity models of spacecraft systems. MSDW is expected to help maximize the scientific return on investment for space missions by understanding early the performance required to have a successful mission while reducing the risk of costly design changes made at late stages in the project life cycle.

  17. Monarch Caterpillar or Larva and Droppings

    An approximately 2 inch long monarch butterfly caterpillar or larva grazes on the leaves of a butterfly weed in a northern Virginia garden. The dark lumps on the leaves around the caterpillar are its droppings or feces....

  18. Shapes of Bubbles and Drops in Motion.

    ERIC Educational Resources Information Center

    O'Connell, James

    2000-01-01

    Explains the shape distortions that take place in fluid packets (bubbles or drops) with steady flow motion by using the laws of Archimedes, Pascal, and Bernoulli rather than advanced vector calculus. (WRM)

  19. Drop impact on chemically structured arrays

    NASA Astrophysics Data System (ADS)

    Mock, Ulrike; Michel, Tobias; Tropea, Cameron; Roisman, Ilia; Rühe, Jürgen

    2005-03-01

    We describe recent investigations on the impact behaviour of liquid drops onto chemically structured surfaces. The surface patterns were prepared via photochemical attachment of polymer molecules with different hydrophilicities using self-assembled monolayers of benzophenone bearing silanes. Immobilization of the polymer monolayers was followed by an ablation process to generate a chemical surface pattern. Impact experiments on systems consisting of very hydrophobic poly(perfluoroalkylethyl)acrylate coatings and hydrophilic areas show that within certain limitations the water drop has a strong tendency to reach the hydrophilic spots, even for inclined substrates. Impact experiments of drops on arrays of hydrophilic spots on the background of a perfluorinated polymer show that the drops spontaneously self-centre on the lithographically generated pattern. The obtained results suggest that the process can be used to circumvent some of the current problems in micro-array fabrication.

  20. Aligner for Elastic Collisions of Dropped Balls.

    ERIC Educational Resources Information Center

    Mellen, Walter Roy

    1995-01-01

    Discusses an aligner that permits dropping a stack of any number of balls of different sizes, elasticities, hardnesses, or types to observe the rebound of the top ball. Experimental results allow a reasonable comparison with theory. (MVL)

  1. Drop impact of shear thickening liquids

    NASA Astrophysics Data System (ADS)

    Boyer, François; Sandoval-Nava, Enrique; Snoeijer, Jacco H.; Dijksman, J. Frits; Lohse, Detlef

    2016-05-01

    The impact of drops of concentrated non-Brownian suspensions (cornstarch and polystyrene spheres) onto a solid surface is investigated experimentally. The spreading dynamics and maximal deformation of the droplet of such shear thickening liquids are found to be markedly different from the impact of Newtonian drops. A particularly striking observation is that the maximal deformation is independent of the drop velocity and that the deformation suddenly stops during the impact phase. Both observations are due to the shear thickening rheology of the suspensions, as is explained theoretically from a balance between the kinetic energy and the viscously dissipated energy, from which we establish a scaling relation between the maximal deformation of the drop and rheological parameters of concentrated suspensions.

  2. Physical Causes of Drop Size Distribution Variability

    NASA Astrophysics Data System (ADS)

    Zawadzki, I.

    Drop size distributions are measured at ground by instruments (disdrometers) that mostly sample one drop at a time or at best, a small number of drops simultaneously. To obtain a representative sample a time window of the observations is required. This introduces a spurious variability due to the differential fall speed of drops coupled with a highly variable field of precipitation in rapid displacement respect to the dis- drometer. A filter has been studied to minimize this spurious variability as well as instrumental uncertainty. The use of filtered data allows to see case to case differences in DSDs that are hidden in the large scatter in the raw data. These differences can be associated to physical processes revealed by a vertically pointing radar such as the de- gree of aggregation, riming, etc. Numerical modeling of particle size evolution using the quasi-stochastic growth equation serves as guide for the understanding of these processes.

  3. Proceedings of the Second International Colloquium on Drops and Bubbles

    NASA Technical Reports Server (NTRS)

    Lecroissette, D. H. (Editor)

    1982-01-01

    Applications of bubble and drop technologies are discussed and include: low gravity manufacturing, containerless melts, microballoon fabrication, ink printers, laser fusion targets, generation of organic glass and metal shells, and space processing. The fluid dynamics of bubbles and drops were examined. Thermomigration, capillary flow, and interfacial tension are discussed. Techniques for drop control are presented and include drop size control and drop shape control.

  4. CT findings of accidental fish bone ingestion and its complications

    PubMed Central

    Venkatesh, Sandeep Halagatti; Karaddi, Nanda Kumar Venkatanarasimha

    2016-01-01

    Fish bone is one of the most common accidentally ingested foreign bodies, and patients commonly present to the emergency department with nonspecific symptoms. Fortunately, most of them are asymptomatic and exit the gastrointestinal tract spontaneously. However, fish bones can get impacted in any part of the aerodigestive tract and cause symptoms. Occasionally, they are asymptomatic initially after ingestion and may present remotely at a later date with serious complications such as gastrointestinal tract perforation, obstruction, and abscess formation. Radiographs are most often negative. High degree of clinical suspicion and familiarity with CT appearance can help to detect fish bone along with any associated complications, and direct further management. We describe and illustrate various CT presentations of ingested fish bone and its complications. PMID:26714057

  5. Accidental blood exposure: risk and prevention in interventional radiology

    PubMed Central

    Vijayananthan, A; Tan, LH; Owen, A; Bhat, R; Edwards, R; Robertson, I; Moss, JG; Nicholls, R

    2006-01-01

    There is a growing concern about the transmission of bloodborne pathogens during medical procedures among health care workers and patients. Over the last three decades, radiological services have undergone many changes with the introduction of new modalities. One of these new disciplines is interventional radiology (IR) which deals with procedures such as arteriography, image-guided biopsies, intravascular catheter insertions, angioplasty and stent placements. Despite these developments, the potential for accidental blood exposure and exposure to other infectious material continues to exist. Therefore, it is important for all radiologists who perform invasive procedures to observe specific recommendations for infection control. In this review, we look at the different policies for protection and universal standards on infection control. PMID:21614335

  6. Accidental intrathecal injection of magnesium sulfate for cesarean section.

    PubMed

    Gilani, Mehryar Taghavi; Zirak, Nahid; Razavi, Majid

    2014-10-01

    Magnesium sulfate is used frequently in the operation room and risks of wrong injection should be considered. A woman with history of pseudocholinesterase enzyme deficiency in the previous surgery was referred for cesarean operation. Magnesium sulfate of 700 mg (3.5 ml of 20% solution) was accidentally administered in the subarachnoid space. First, the patient had warm sensation and cutaneous anesthesia, but due to deep tissue pain, general anesthesia was induced by thiopental and atracurium. After the surgery, muscle relaxation and lethargy remained. At 8-10 h later, muscle strength improved and train of four (TOF) reached over 0.85, and then the endotracheal tube was removed. The patient was evaluated during the hospital stay and on the anesthesia clinic. No neurological symptoms, headache or backache were reported. Due to availability of magnesium sulfate, we should be careful for inadvertent intravenous, spinal and epidural injection; therefore before injection must be double checked. PMID:25422620

  7. Cardiotoxic effect due to accidental ingestion of an organic solvent.

    PubMed

    Cieślik-Guerra, Urszula Izabela; Rechciński, Tomasz; Trzos, Ewa; Wierzbowska-Drabik, Karina; Uznańska-Loch, Barbara; Winnicka, Renata; Krakowiak, Anna; Kasprzak, Jarosław Damian; Fröhlich, Colin; Kurpesa, Małgorzata

    2015-01-01

    Toxic myocardial injury can be misdiagnosed as a myocardial infarction, resulting in the patient undergoing standard treatment for cardiac rehabilitation. However, such inadequate therapeutic strategies can lead to cardiovascular complications including dilated cardiomyopathy. This study presents a case of a 65-year-old man after accidental ingestion of organic solvents (toluene and xylene), whose condition demonstrated all the criteria for diagnosis of myocardial infarction. The qualitative determinations of the above mentioned volatile organic compounds (VOCs) in whole blood were carried out using a headspace sampling by means of gas chromatography. Cardiac catheterization revealed no specific coronary lesions, only a muscular bridge causing a 30-50% stenosis in the middle of the circumflex branch of the left coronary artery. PMID:26159958

  8. Correcting for accidental correlations in saturated avalanche photodiodes

    NASA Astrophysics Data System (ADS)

    Grieve, J. A.; Chandrasekara, R.; Tang, Z.; Cheng, C.; Ling, A.

    2016-02-01

    In this paper we present a general method for estimating rates of accidental coincidence between a pair of single photon detectors operated within their saturation regimes. By folding the effects of recovery time of both detectors and the detection circuit into an "effective duty cycle" we are able to accomodate complex recovery behaviour at high event rates. As an example, we provide a detailed high-level model for the behaviour of passively quenched avalanche photodiodes, and demonstrate effective background subtraction at rates commonly associated with detector saturation. We show that by post-processing using the updated model, we observe an improvement in polarization correlation visibility from 88.7% to 96.9% in our experimental dataset. This technique will be useful in improving the signal-to-noise ratio in applications which depend on coincidence measurements, especially in situations where rapid changes in flux may cause detector saturation.

  9. Dose assessment of an accidental exposure at the IPNS

    SciTech Connect

    Campos Torres, M.M.

    1995-02-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose ranged from 550 mrem/min to 2850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenetic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  10. Detection of accidental oesophageal intubation. Role of the anaesthetic assistant.

    PubMed

    Cameron, A E; Hyde, R A; Sivalingam, P; Asbury, A J

    1997-08-01

    Three situations in which an anaesthetic assistant might be able to detect accidental oesophageal intubation during or immediately after intubation were assessed. These were: firstly, whilst applying cricoid pressure, secondly, whilst applying gentle palpation over the trachea just above the suprasternal notch and, thirdly, after intubation by means of a 'roll test'. During cricoid pressure, tracheal intubation was correctly diagnosed in all of 10 cases. However, deliberate oesophageal intubation was only detected in six out of 10 cases. During suprasternal palpation, three cases out of 10 oesophageal and three cases out of 10 tracheal intubation were misdiagnosed. In the 'roll test', two out of 10 tracheal and five out of 10 oesophageal intubations were misdiagnosed. In conclusion, no method could be relied on entirely and may indeed give false reassurance. Nonetheless, any doubt expressed about the tracheal tube position by the assistant should be taken seriously and a careful check made. PMID:9291756

  11. Accidental low velocity atypical missile injury to the head.

    PubMed

    Chattopadhyay, Saurabh

    2008-12-01

    Missile injuries on the head are mostly due to firearms. Atypical missiles may be encountered in case of shrapnel of bomb explosions but rarely because of stones. The present case is a rare case where a stone propelled by the pressure from the rear wheel of a speeding truck on the highway, struck the head of a 7-year-old girl resulting in fatality. Reconstruction of the incident on the basis of history and postmortem findings throws some light on the mechanism. The case is unique as it is the first reported case of an accidental missile injury to the head resulting in fatality without any direct human involvement for propulsion of the projectile. PMID:19259020

  12. Dose assessment of an accidental exposure at IPNS

    SciTech Connect

    Torres, M.M.C.

    1996-05-01

    Seven different methods were used to estimate the dose rate to a female worker who was accidentally exposed in the neutron PHOENIX beamline at the IPNS. Theoretical and measured entrance dose rates ranged from 550 mrem/min to 2,850 mrem/min. Theoretical estimates were based on a Monte Carlo simulation of a spectrum provided by IPNS (Crawford Spectrum). Dose measurements were made with TLDs on phantoms and with ionization chambers in a water phantom. Estimates of the whole body total effective dose equivalent (TEDE) rate ranged from 5.2 mrem/min to 840 mrem/min. Assumed and measured quality factors ranged from 2.6 to 11.8. Cytogenic analyses of blood samples detected no positive exposure. The recommended TEDE rate was 158 mrem/min. The TEDE was 750 mrem.

  13. CT findings of accidental fish bone ingestion and its complications.

    PubMed

    Venkatesh, Sandeep Halagatti; Venkatanarasimha Karaddi, Nanda Kumar

    2016-01-01

    Fish bone is one of the most common accidentally ingested foreign bodies, and patients commonly present to the emergency department with nonspecific symptoms. Fortunately, most of them are asymptomatic and exit the gastrointestinal tract spontaneously. However, fish bones can get impacted in any part of the aerodigestive tract and cause symptoms. Occasionally, they are asymptomatic initially after ingestion and may present remotely at a later date with serious complications such as gastrointestinal tract perforation, obstruction, and abscess formation. Radiographs are most often negative. High degree of clinical suspicion and familiarity with CT appearance can help to detect fish bone along with any associated complications, and direct further management. We describe and illustrate various CT presentations of ingested fish bone and its complications. PMID:26714057

  14. Clinical Signs and Pathology of Accidental Monensin Poisoning in Sheep

    PubMed Central

    Nation, P. N.; Crowe, S. P.; Harries, W. N.

    1982-01-01

    The clinical signs and postmortem findings in sheep from two flocks accidentally poisoned with monensin are described. Clinical signs began within 24 hours of exposure to monensin. In the acute stages they consisted of lethargy, stiffness, muscular weakness, a stilted gait and recumbency. Feed refusal was seen in one flock but not in the second. Subacute to chronic clinical signs were decreased muscle volume of the rump and thigh. When forced to run, chronically affected sheep had a stilted, stiff legged, rocking horse gait. Gross postmortem changes were not always visible. Where visible, they affected skeletal muscles and consisted of pale streaking, with atrophy in the chronic stages. Lesions were most severe in muscles of the rump and hind limbs. Microscopically myofiber swelling and hyalinization were seen with interstitial mononuclear cell reaction and extensive sarcoplasmic mineralization in some cases. Chronic lesions consisted of fibrosis and myofiber atrophy. In lambs less than one month old, diffuse gastrointestinal hemorrhage was the only finding. PMID:17422198

  15. Correcting for accidental correlations in saturated avalanche photodiodes.

    PubMed

    Grieve, J A; Chandrasekara, R; Tang, Z; Cheng, C; Ling, A

    2016-02-22

    In this paper we present a general method for estimating rates of accidental coincidence between a pair of single photon detectors operated within their saturation regimes. By folding the effects of recovery time of both detectors and the detection circuit into an "effective duty cycle" we are able to accomodate complex recovery behaviour at high event rates. As an example, we provide a detailed high-level model for the behaviour of passively quenched avalanche photodiodes, and demonstrate effective background subtraction at rates commonly associated with detector saturation. We show that by post-processing using the updated model, we observe an improvement in polarization correlation visibility from 88.7% to 96.9% in our experimental dataset. This technique will be useful in improving the signal-to-noise ratio in applications which depend on coincidence measurements, especially in situations where rapid changes in flux may cause detector saturation. PMID:26907016

  16. Successful outcome of accidental ethylene glycol poisoning despite delayed presentation

    PubMed Central

    Mangera, Zaheer; Isse, Said; Winnett, Georgia; Lal, Aroon; Cafferkey, Michele

    2010-01-01

    A 69-year-old man presented to the emergency department after being found unconscious by his son. He had experienced headache the previous day but had been otherwise well. Investigations revealed a severe metabolic acidosis, raised lactate and acute kidney injury. The calculated anion and osmolar gap were both elevated at 37.7 and 39.3, respectively. Due to his reduced Glasgow coma score (GCS) he was intubated and a CT scan performed: only a small, mature pontine infarct was found of uncertain significance. Further questioning of the family revealed accidental ingestion of 150 ml of a ‘blue liquid’ 24 h earlier (later identified as car screenwash). With ethylene glycol (EG) poisoning suspected, he was given intravenous ethanol, fomepizole (a competitive inhibitor of alcohol dehydrogenase) and haemofiltration. Despite the delayed presentation, prompt recognition and treatment of EG poisoning led to a successful discharge in this case. PMID:22767560

  17. Pressure drop in flashing flow through obstructions

    NASA Astrophysics Data System (ADS)

    Weinle, M. E.; Johnston, B. S.

    1985-12-01

    An experiment was designed to investigate the pressure drop for flashing flow across obstructions of different geometries at various flow rates. Tests were run using two different orifices to determine if the two-phase pressure drop could be characterized by the single phase loss coefficient and the general behavior of the two-phase multiplier. For the geometries studied, it was possible to correlate the multiplier in a geometry-independent fashion.

  18. Blood drop patterns: Formation and applications.

    PubMed

    Chen, Ruoyang; Zhang, Liyuan; Zang, Duyang; Shen, Wei

    2016-05-01

    The drying of a drop of blood or plasma on a solid substrate leads to the formation of interesting and complex patterns. Inter- and intra-cellular and macromolecular interactions in the drying plasma or blood drop are responsible for the final morphologies of the dried patterns. Changes in these cellular and macromolecular components in blood caused by diseases have been suspected to cause changes in the dried drop patterns of plasma and whole blood, which could be used as simple diagnostic tools to identify the health of humans and livestock. However, complex physicochemical driving forces involved in the pattern formation are not fully understood. This review focuses on the scientific development in microscopic observations and pattern interpretation of dried plasma and whole blood samples, as well as the diagnostic applications of pattern analysis. Dried drop patterns of plasma consist of intricate visible cracks in the outer region and fine structures in the central region, which are mainly influenced by the presence and concentration of inorganic salts and proteins during drying. The shrinkage of macromolecular gel and its adhesion to the substrate surface have been thought to be responsible for the formation of the cracks. Dried drop patterns of whole blood have three characteristic zones; their formation as functions of drying time has been reported in the literature. Some research works have applied engineering treatment to the evaporation process of whole blood samples. The sensitivities of the resultant patterns to the relative humidity of the environment, the wettability of the substrates, and the size of the drop have been reported. These research works shed light on the mechanisms of spreading, evaporation, gelation, and crack formation of the blood drops on solid substrates, as well as on the potential applications of dried drop patterns of plasma and whole blood in diagnosis. PMID:26988066

  19. On the Stability of Rotating Drops

    PubMed Central

    Nurse, A. K.; Coriell, S. R.; McFadden, G. B.

    2015-01-01

    We consider the equilibrium and stability of rotating axisymmetric fluid drops by appealing to a variational principle that characterizes the equilibria as stationary states of a functional containing surface energy and rotational energy contributions, augmented by a volume constraint. The linear stability of a drop is determined by solving the eigenvalue problem associated with the second variation of the energy functional. We compute equilibria corresponding to both oblate and prolate shapes, as well as toroidal shapes, and track their evolution with rotation rate. The stability results are obtained for two cases: (i) a prescribed rotational rate of the system (“driven drops”), or (ii) a prescribed angular momentum (“isolated drops”). For families of axisymmetric drops instabilities may occur for either axisymmetric or non-axisymmetric perturbations; the latter correspond to bifurcation points where non-axisymmetric shapes are possible. We employ an angle-arc length formulation of the problem which allows the computation of equilibrium shapes that are not single-valued in spherical coordinates. We are able to illustrate the transition from spheroidal drops with a strong indentation on the rotation axis to toroidal drops that do not extend to the rotation axis. Toroidal drops with a large aspect ratio (major radius to minor radius) are subject to azimuthal instabilities with higher mode numbers that are analogous to the Rayleigh instability of a cylindrical interface. Prolate spheroidal shapes occur if a drop of lower density rotates within a denser medium; these drops appear to be linearly stable. This work is motivated by recent investigations of toroidal tissue clusters that are observed to climb conical obstacles after self-assembly [Nurse et al., Journal of Applied Mechanics 79 (2012) 051013]. PMID:26958440

  20. La Gocciolina (The Little Drop of Water).

    ERIC Educational Resources Information Center

    Palandra, Maria

    This primary level reader in Italian intended for use in a bilingual education setting, is about the life cycle of a drop of water. The drop of water is personified and the story tells of its adventures as it travels from the top of the lake to the bottom, its meeting with the inhabitants of the lake, and its trip to the clouds. After deciding not…

  1. Containing the accidental laboratory escape of potential pandemic influenza viruses

    PubMed Central

    2013-01-01

    Background The recent work on the modified H5N1 has stirred an intense debate on the risk associated with the accidental release from biosafety laboratory of potential pandemic pathogens. Here, we assess the risk that the accidental escape of a novel transmissible influenza strain would not be contained in the local community. Methods We develop here a detailed agent-based model that specifically considers laboratory workers and their contacts in microsimulations of the epidemic onset. We consider the following non-pharmaceutical interventions: isolation of the laboratory, laboratory workers’ household quarantine, contact tracing of cases and subsequent household quarantine of identified secondary cases, and school and workplace closure both preventive and reactive. Results Model simulations suggest that there is a non-negligible probability (5% to 15%), strongly dependent on reproduction number and probability of developing clinical symptoms, that the escape event is not detected at all. We find that the containment depends on the timely implementation of non-pharmaceutical interventions and contact tracing and it may be effective (>90% probability per event) only for pathogens with moderate transmissibility (reproductive number no larger than R0 = 1.5). Containment depends on population density and structure as well, with a probability of giving rise to a global event that is three to five times lower in rural areas. Conclusions Results suggest that controllability of escape events is not guaranteed and, given the rapid increase of biosafety laboratories worldwide, this poses a serious threat to human health. Our findings may be relevant to policy makers when designing adequate preparedness plans and may have important implications for determining the location of new biosafety laboratories worldwide. PMID:24283203

  2. Accidental Durotomy in Minimally Invasive Transforaminal Lumbar Interbody Fusion: Frequency, Risk Factors, and Management

    PubMed Central

    Volz, Florian; Krüger, Marie T.; Kogias, Evangelos; Rölz, Roland; Sircar, Ronen; Hubbe, Ulrich

    2015-01-01

    Purpose. To assess the frequency, risk factors, and management of accidental durotomy in minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). Methods. This single-center study retrospectively investigates 372 patients who underwent MIS TLIF and were mobilized within 24 hours after surgery. The frequency of accidental durotomies, intraoperative closure technique, body mass index, and history of previous surgery was recorded. Results. We identified 32 accidental durotomies in 514 MIS TLIF levels (6.2%). Analysis showed a statistically significant relation of accidental durotomies to overweight patients (body mass index ≥25 kg/m2; P = 0.0493). Patient age older than 65 years tended to be a positive predictor for accidental durotomies (P = 0.0657). Mobilizing patients on the first postoperative day, we observed no durotomy-associated complications. Conclusions. The frequency of accidental durotomies in MIS TLIF is low, with overweight being a risk factor for accidental durotomies. The minimally invasive approach seems to minimize durotomy-associated complications (CSF leakage, pseudomeningocele) because of the limited dead space in the soft tissue. Patients with accidental durotomy can usually be mobilized within 24 hours after MIS TLIF without increased risk. The minimally invasive TLIF technique might thus be beneficial in the prevention of postoperative immobilization-associated complications such as venous thromboembolism. This trial is registered with DRKS00006135. PMID:26075294

  3. Involving Parents in Indicated Early Intervention for Childhood PTSD Following Accidental Injury

    ERIC Educational Resources Information Center

    Cobham, Vanessa E.; March, Sonja; De Young, Alexandra; Leeson, Fiona; Nixon, Reginald; McDermott, Brett; Kenardy, Justin

    2012-01-01

    Accidental injuries represent the most common type of traumatic event to which a youth is likely to be exposed. While the majority of youth who experience an accidental injury will recover spontaneously, a significant proportion will go on to develop Post-Traumatic Stress Disorder (PTSD). And yet, there is little published treatment outcome

  4. 21 CFR 369.9 - General warnings re accidental ingestion by children.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false General warnings re accidental ingestion by... SERVICES (CONTINUED) DRUGS FOR HUMAN USE INTERPRETATIVE STATEMENTS RE WARNINGS ON DRUGS AND DEVICES FOR OVER-THE-COUNTER SALE Definitions and Interpretations § 369.9 General warnings re accidental...

  5. 21 CFR 369.9 - General warnings re accidental ingestion by children.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 5 2011-04-01 2011-04-01 false General warnings re accidental ingestion by... SERVICES (CONTINUED) DRUGS FOR HUMAN USE INTERPRETATIVE STATEMENTS RE WARNINGS ON DRUGS AND DEVICES FOR OVER-THE-COUNTER SALE Definitions and Interpretations § 369.9 General warnings re accidental...

  6. Involving Parents in Indicated Early Intervention for Childhood PTSD Following Accidental Injury

    ERIC Educational Resources Information Center

    Cobham, Vanessa E.; March, Sonja; De Young, Alexandra; Leeson, Fiona; Nixon, Reginald; McDermott, Brett; Kenardy, Justin

    2012-01-01

    Accidental injuries represent the most common type of traumatic event to which a youth is likely to be exposed. While the majority of youth who experience an accidental injury will recover spontaneously, a significant proportion will go on to develop Post-Traumatic Stress Disorder (PTSD). And yet, there is little published treatment outcome…

  7. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 10. CONTROL OF ACCIDENTAL RELEASES OF HYDROGEN CYANIDE

    EPA Science Inventory

    The report discusses the control of accidental releases of hydrogen cyanide (HCN) to the atmosphere. HCN has an IDLH (immediately dangerous to life and health) concentration of 50 ppm, making it an acute toxic hazard. Reducing the risk associated with an accidental release of HCN...

  8. Accidentes en plantas nucleares de electricidad y el riesgo de cáncer

    Cancer.gov

    Hoja informativa acerca de los riesgos del cáncer asociados con accidentes en plantas nucleares de electricidad. Incluye información para pacientes con cáncer que viven en una zona que puede haber sido afectada por un accidente en una planta nuclear.

  9. Drops can bounce from perfectly hydrophilic surfaces

    NASA Astrophysics Data System (ADS)

    Kolinski, J. M.; Mahadevan, L.; Rubinstein, S. M.

    2014-10-01

    Drops are well known to rebound from superhydrophobic surfaces and from liquid surfaces. Here, we show that drops can also rebound from a superhydrophilic solid surface such as an atomically smooth mica sheet. However, the coefficient of restitution CR associated with this process is significantly lower than that associated with rebound from superhydrophobic surfaces. A direct imaging method allows us to characterize the dynamics of the deformation of the drop in entering the vicinity of the surface. We find that drop bouncing occurs without the drop ever touching the solid and there is a nanometer-scale film of air that separates the liquid and solid, suggesting that shear in the air film is the dominant source of dissipation during rebound. Furthermore, we see that any discrete nanometer-height defects on an otherwise hydrophilic surface, such as treated glass, completely inhibits the bouncing of the drop, causing the liquid to wet the surface. Our study adds a new facet to the dynamics of droplet impact by emphasizing that the thin film of air can play a role not just in the context of splashing but also bouncing, while highlighting the role of rare surface defects in inhibiting this response.

  10. Toroidal bubble entrapment under an impacting drop

    NASA Astrophysics Data System (ADS)

    Thoraval, Marie-Jean; Thoroddsen, Sigurdur T.; Takehara, Kohsei; Etoh, Takeharu Goji

    2012-11-01

    We use ultra-high-speed imaging and numerical simulations (GERRIS, http://gfs.sf.net) to observe and analyze the formation of up to 14 air tori when a water drop impacts on a thin liquid film of water or other miscible liquids. They form during the early contact between the drop and the pool by the vertical oscillations of the ejecta sheet. They then break in micro-bubble rings by the Rayleigh instability. Their formation is associated with the shedding of an axisymmetric vortex street into the liquid from the free surface. These vorticity structures and their dynamics are made apparent by the dynamics of the micro-bubbles, added seed particles and the difference of refractive index for different liquids in the drop and the pool. More robust entrapments are observed for a thin film of ethanol or methanol. We show that while the non-spherical drop shape is not responsible for the toroidal bubble entrapments, the number of rings is increasing for more oblate drops. Individual bubble entrapments are also observed from azimuthal destabilizations of the neck between the drop and the pool.

  11. Airflows generated by an impacting drop.

    PubMed

    Bischofberger, Irmgard; Ray, Bahni; Morris, Jeffrey F; Lee, Taehun; Nagel, Sidney R

    2016-03-16

    A drop impacting a solid surface with sufficient velocity will splash and emit many small droplets. However, lowering the ambient air pressure suppresses splashing completely. This effect, robustly found for different liquid and substrate properties, raises the fundamental question of how air affects a spreading drop. In a combined experimental and numerical study we characterize the flow of air induced by the drop after it hits the substrate, using a modified Schlieren optics technique combined with high-speed video imaging and Lattice-Boltzmann simulations. Our experiments reveal the emergence of air structures on different length scales. On large scales, the airflow induced in the drop's wake leads to vortex structures due to interaction with the substrate. On smaller scales, we visualize a ring structure above the outer edge of the spreading liquid generated by the spreading of the drop. Our simulations reveal the interaction between the wake vorticity and the flows originating from the rapidly escaping air from below the impacting drop. We show that the vorticity is governed by a balance between inertial and viscous forces in the air, and is unrelated to the splashing threshold. PMID:26809314

  12. Air flows generated by an impacting drop

    NASA Astrophysics Data System (ADS)

    Bischofberger, Irmgard; Ray, Bahni; Lee, Taehun; Morris, Jeff; Nagel, Sidney R.; University of Chicago Collaboration; CCNY Collaboration

    2015-03-01

    A drop impacting a solid surface with sufficient velocity will splash and emit many small droplets. Lowering the ambient air pressure suppresses splashing completely. This effect, robustly found for different liquid and substrate properties, raises the fundamental question of how air affects a spreading drop. We visualize the flow of air induced by the drop after it hits the substrate using a modified Schlieren optics technique combined with high-speed video imaging. Comparison with the air flow created by an impacting solid sphere allows us to decouple the vorticity components of the falling drop from that of the spreading liquid. Our studies reveal the emergence of vorticity on two length scales. On larger scales, the airflow induced in the drop's wake leads to vortex structures due to interaction with the substrate. On smaller scales, the spreading of the drop generates a vortex ring above the outer edge of the spreading liquid. We show that this vorticity generation is governed by a balance between inertial and viscous forces.

  13. A spreading drop of shallow water

    NASA Astrophysics Data System (ADS)

    Jarecka, Dorota; Jaruga, Anna; Smolarkiewicz, Piotr K.

    2015-05-01

    The theoretical solutions and corresponding numerical simulations of Schär and Smolarkiewicz (1996) [3] are revisited. The original abstract problem of a parabolic, slab-symmetric drop of shallow water spreading under gravity is extended to three spatial dimensions, with the initial drop defined over an elliptical compact support. An axisymmetric drop is considered as a special case. The elliptical drop exhibits enticing dynamics, which may appear surprising at the first glance. In contrast, the evolution of the axisymmetric drop is qualitatively akin to the evolution of the slab-symmetric drop and intuitively obvious. Besides being interesting per se, the derived theoretical results provide a simple means for testing numerical schemes concerned with wetting-drying areas in shallow water flows. Reported calculations use the libmpdata++, a recently released free/libre and open-source software library of solvers for generalized transport equations. The numerical results closely match theoretical predictions, demonstrating strengths of the nonoscillatory forward-in-time integrators comprising the libmpdata++.

  14. Leidenfrost drops on liquid baths: theory

    NASA Astrophysics Data System (ADS)

    Sobac, Benjamin; Rednikov, Alexei; Maquet, Laurent; Darbois-Texier, Baptiste; Duchesne, Alexis; Brandenbourger, Martin; Dorbolo, Stéphane; Colinet, Pierre

    2015-11-01

    It is well known that a liquid drop released over a very hot surface generally does not contact the surface nor boils but rather levitates over a thin vapor film generated by its own evaporation (Leidenfrost effect). In particular, the case of a hot (and flat) solid substrate has been extensively studied in recent years. In contrast, we here focus on Leidenfrost drops over a superheated liquid bath, addressing the problem theoretically and comparing our predictions with experimental results, detailed in a separate talk. We predict the geometry of the drop and of the liquid bath, based on the hydrostatic Young-Laplace and lubrication equations. A good agreement is observed with the available experimental data concerning the deformation of the liquid bath. The modeling also yields a rather complete insight into the shape of the drop. As in the case of a solid substrate, the vapor layer generally appears to be composed of a vapor pocket surrounded by a circular neck. The influences of the superheat and of the drop size are parametrically investigated. A number of scaling laws are established. Unlike the case of a solid substrate, no chimney instability was found in the range of drop size studied.

  15. Hanging drop crystal growth apparatus and method

    NASA Technical Reports Server (NTRS)

    Carter, Daniel C. (Inventor); Smith, Robbie E. (Inventor)

    1989-01-01

    An apparatus (10) is constructed having a cylindrical enclosure (16) within which a disc-shaped wicking element (18) is positioned. A well or recess (22) is cut into an upper side (24) of this wicking element, and a glass cover plate or slip (28) having a protein drop disposed thereon is sealably positioned on the wicking element (18), with drop (12) being positioned over well or recess (22). A flow of control fluid is generated by a programmable gradient former (16), with this control fluid having a vapor pressure that is selectively variable. This flow of control fluid is coupled to the wicking element (18) where control fluid vapor diffusing from walls (26) of the recess (22) is exposed to the drop (12), forming a vapor pressure gradient between the drop (12) and the control fluid vapor. Initially, this gradient is adjusted to draw solvent from the drop (12) at a relatively high rate, and as the critical supersaturation point is approached (the point at which crystal nucleation occurs), the gradient is reduced to more slowly draw solvent from the drop (12). This allows discrete protein molecules more time to orient themselves into an ordered crystalline lattice, producing protein crystals which, when processed by X-ray crystallography, possess a high degree of resolution.

  16. Learning from global emissions scenarios

    NASA Astrophysics Data System (ADS)

    O'Neill, Brian C.; Nakicenovic, Nebojsa

    2008-10-01

    Scenarios of global greenhouse gas emissions have played a key role in climate change analysis for over twenty years. Currently, several research communities are organizing to undertake a new round of scenario development in the lead-up to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). To help inform this process, we assess a number of past efforts to develop and learn from sets of global greenhouse gas emissions scenarios. We conclude that while emissions scenario exercises have likely had substantial benefits for participating modeling teams and produced insights from individual models, learning from the exercises taken as a whole has been more limited. Model comparison exercises have typically focused on the production of large numbers of scenarios while investing little in assessing the results or the production process, perhaps on the assumption that later assessment efforts could play this role. However, much of this assessment potential remains untapped. Efforts such as scenario-related chapters of IPCC reports have been most informative when they have gone to extra lengths to carry out more specific comparison exercises, but in general these assessments do not have the remit or resources to carry out the kind of detailed analysis of scenario results necessary for drawing the most useful conclusions. We recommend that scenario comparison exercises build-in time and resources for assessing scenario results in more detail at the time when they are produced, that these exercises focus on more specific questions to improve the prospects for learning, and that additional scenario assessments are carried out separately from production exercises. We also discuss the obstacles to better assessment that might exist, and how they might be overcome. Finally, we recommend that future work include much greater emphasis on understanding how scenarios are actually used, as a guide to improving scenario production.

  17. The changing nutrition scenario

    PubMed Central

    Gopalan, C.

    2013-01-01

    The past seven decades have seen remarkable shifts in the nutritional scenario in India. Even up to the 1950s severe forms of malnutrition such as kwashiorkar and pellagra were endemic. As nutritionists were finding home-grown and common-sense solutions for these widespread problems, the population was burgeoning and food was scarce. The threat of widespread household food insecurity and chronic undernutrition was very real. Then came the Green Revolution. Shortages of food grains disappeared within less than a decade and India became self-sufficient in food grain production. But more insidious problems arising from this revolution were looming, and cropping patterns giving low priority to coarse grains and pulses, and monocropping led to depletion of soil nutrients and Green Revolution fatigue. With improved household food security and better access to health care, clinical manifestations of severe malnutrition virtually disappeared. But the decline in chronic undernutrition and hidden hunger from micronutrient deficiencies was slow. On the cusp of the new century, an added factor appeared on the nutritional scene in India. With steady urban migration, upward mobility out of poverty, and an increasingly sedentary lifestyle because of improvements in technology and transport, obesity rates began to increase, resulting in a dual burden. Measured in terms of its performance in meeting its Millennium Development Goals, India has fallen short. Despite its continuing high levels of poverty and illiteracy, India has a huge demographic potential in the form of a young population. This advantage must be leveraged by investing in nutrition education, household access to nutritious diets, sanitary environment and a health-promoting lifestyle. This requires co-operation from all the stakeholders, including governments, non government organizations, scientists and the people at large. PMID:24135189

  18. The changing nutrition scenario.

    PubMed

    Gopalan, C

    2013-09-01

    The past seven decades have seen remarkable shifts in the nutritional scenario in India. Even up to the 1950s severe forms of malnutrition such as kwashiorkar and pellagra were endemic. As nutritionists were finding home-grown and common-sense solutions for these widespread problems, the population was burgeoning and food was scarce. The threat of widespread household food insecurity and chronic undernutrition was very real. Then came the Green Revolution. Shortages of food grains disappeared within less than a decade and India became self-sufficient in food grain production. But more insidious problems arising from this revolution were looming, and cropping patterns giving low priority to coarse grains and pulses, and monocropping led to depletion of soil nutrients and 'Green Revolution fatigue'. With improved household food security and better access to health care, clinical manifestations of severe malnutrition virtually disappeared. But the decline in chronic undernutrition and "hidden hunger" from micronutrient deficiencies was slow. On the cusp of the new century, an added factor appeared on the nutritional scene in India. With steady urban migration, upward mobility out of poverty, and an increasingly sedentary lifestyle because of improvements in technology and transport, obesity rates began to increase, resulting in a dual burden. Measured in terms of its performance in meeting its Millennium Development Goals, India has fallen short. Despite its continuing high levels of poverty and illiteracy, India has a huge demographic potential in the form of a young population. This advantage must be leveraged by investing in nutrition education, household access to nutritious diets, sanitary environment and a health-promoting lifestyle. This requires co-operation from all the stakeholders, including governments, non government organizations, scientists and the people at large. PMID:24135189

  19. Handling emergency management training scenarios: The MUSTER SCENARIO MANAGER

    SciTech Connect

    Andersen, H.B.; Andersen, V.; Larsen, M.S.

    1995-12-31

    The SCENARIO MANAGER is a module within the MUSTER system: a prototype computer system supporting the multi-user training of emergency managers and their staff in coordinating activities to cope with emergencies. The SCENARIO MANAGER has been designed to meet the requirements of training supervisors, that is, the persons (including aides) who plan, execute and analyze training sessions for emergency management trainees.

  20. Air entrainment in the primary impact of single drops on a free liquid surface

    NASA Astrophysics Data System (ADS)

    Salerno, E.; Levoni, P.; Barozzi, G. S.

    2015-11-01

    Air-bubble entrainment produced by the impact of water drops on a liquid pool is investigated with the use of high-speed imaging. A wide range of drop volumes and impact velocities is considered to determine how the entrainment mechanisms change with varying the impact conditions. Five different entrainment regimes are distinguished on the basis of the observed flow phenomena. Their characteristic features are described in terms of bubble formation, crater evolution, jetting and secondary drop ejection. A regime map is reconstructed in the Froude-Weber space. Results obtained in the present study show good agreement with the phase diagrams reported in the literature and contribute to complete the scenario of the entrainment regimes. Quantitative data about the size and the residence times of the entrained nuclei are also presented.

  1. B-52B/DTV (Drop Test Vehicle) flight test results: Drop test missions

    NASA Technical Reports Server (NTRS)

    Doty, L. J.

    1985-01-01

    The NASA test airplane, B-52B-008, was a carrier for drop tests of the shuttle booster recovery parachute system. The purpose of the test support by Boeing was to monitor the vertical loads on the pylon hooks. The hooks hold the Drop Test Vehicle to the B-52 pylon during drop test missions. The loads were monitored to assure the successful completion of the flight and the safety of the crew.

  2. Impact of a single drop on the same liquid: formation, growth and disintegration of jets

    NASA Astrophysics Data System (ADS)

    Agbaglah, G. Gilou; Deegan, Robert

    2015-11-01

    One of the simplest splashing scenarios results from the impact of a single drop on on the same liquid. The traditional understanding of this process is that the impact generates a jet that later breaks up into secondary droplets. Recently it was shown that even this simplest of scenarios is more complicated than expected because multiple jets can be generated from a single impact event and there are bifurcations in the multiplicity of jets. First, we study the formation, growth and disintegration of jets following the impact of a drop on a thin film of the same liquid using a combination of numerical simulations and linear stability theory. We obtain scaling relations from our simulations and use these as inputs to our stability analysis. We also use experiments and numerical simulations of a single drop impacting on a deep pool to examine the bifurcation from a single jet into two jets. Using high speed X-ray imaging methods we show that vortex separation within the drop leads to the formation of a second jet long after the formation of the ejecta sheet.

  3. Futures Scenario in Science Learning

    ERIC Educational Resources Information Center

    Lloyd, David; Vanderhout, Annastasia; Lloyd, Lisa; Atkins, David

    2010-01-01

    In this article we describe our experiences in developing futures scenarios in two science contexts, space science and atmospheric science/climate change. Futures scenario writing can develop scientific literacy by connecting science learning to students' lifeworlds--past, present and future. They also provide a synthesising mechanism for…

  4. Japanese National Standards: Learning Scenarios.

    ERIC Educational Resources Information Center

    Indiana Univ., Bloomington. Indiana Teachers of Japanese.

    This small manual presents 12 learning scenarios designed to teach the Japanese national learning standards to American learners of Japanese. It is written by teachers for teachers. These scenarios are designed to teach interpersonal, interpretive, and presentational communication; practices and products of culture; cultural comparisons; language

  5. Self-Diffusion of Drops in a Dilute Sheared Emulsion

    NASA Technical Reports Server (NTRS)

    Loewenberg, Michael; Hinch, E. J.

    1996-01-01

    Self-diffusion coefficients that describe cross-flow migration of non-Brownian drops in a dilute sheared emulsion were obtained by trajectory calculations. A boundary integral formulation was used to describe pairwise interactions between deformable drops; interactions between undeformed drops were described with mobility functions for spherical drops. The results indicate that drops have large anisotropic self-diffusivities which depend strongly on the drop viscosity and modestly on the shear-rate. Pairwise interactions between drops in shear-flow do not appreciably promote drop breakup.

  6. Drop impact on inclined superhydrophobic surfaces

    NASA Astrophysics Data System (ADS)

    Choi, Wonjae; Leclear, Sani; Leclear, Johnathon; Abhijeet, .; Park, Kyoo-Chul

    We report an empirical study and dimensional analysis on the impact patterns of water drops on inclined superhydrophobic surfaces. While the classic Weber number determines the spreading and recoiling dynamics of a water drop on a horizontal / smooth surface, for a superhydrophobic surface, the dynamics depends on two distinct Weber numbers, each calculated using the length scale of the drop or of the pores on the surface. Impact on an inclined superhydrophobic surface is even more complicated, as the velocity that determines the Weber number is not necessarily the absolute speed of the drop but the velocity components normal and tangential to the surface. We define six different Weber numbers, using three different velocities (absolute, normal and tangential velocities) and two different length scales (size of the drop and of the texture). We investigate the impact patterns on inclined superhydrophobic surfaces with three different types of surface texture: (i) posts, (ii) ridges aligned with and (iii) ridges perpendicular to the impact direction. Results suggest that all six Weber numbers matter, but affect different parts of the impact dynamics, ranging from the Cassie-Wenzel transition, maximum spreading, to anisotropic deformation. We acknowledge financial support from the Office of Naval Research (ONR) through Contract 3002453812.

  7. Computational Analysis of Dynamics of Drop Formation

    NASA Astrophysics Data System (ADS)

    Wilkes, E. D.; Basaran, O. A.

    1997-11-01

    The dynamics of growth and detachment of a drop from a capillary tube are of importance in applications including measurement of dynamic surface tension, ink-jet printing, and separations. While this problem has previously been studied both experimentally and theoretically either using one-dimensional equations or treating the flow as inviscid, here the full nonlinear, transient Navier-Stokes system is solved in two dimensions to analyze the dynamics at finite Reynolds numbers. A finite element algorithm incorporating a multi-region computational mesh which conforms to the shape of the drop is used to capture the time evolution of the interface shape, including that of a long and thin neck as the drop nears detachment. The dynamics is studied over virtually the entire parameter space of practical importance spanned by Reynolds (Re), capillary (Ca), and gravitational Bond (G) numbers. At low values of Ca and G, the drops grow as sections of spheres for significant extents of time. These results show that when the drop is nearly a hemisphere, the pressure inside it is fairly uniform and virtually equal to the capillary pressure on account of the smallness of the viscous stresses. Such conditions provide an optimal setting for making static as well as dynamic surface tension measurements. When G and/or Ca are both moderate or large, special attention is paid to the neck as it develops and breaks.

  8. Elastic wave effects in viscoelastic drop deformation

    NASA Astrophysics Data System (ADS)

    Sarkar, Kausik

    2002-11-01

    Flow induced drop deformation critically affects the behavior of emulsions. Moreover, single drop dynamics assumes importance in microfluidic applications, liposome based targeted drug delivery, and contrast agents for medical imaging. We have been engaged in a computational study of the deformation history of a single drop in imposed time-periodic viscous flows. Previously, we reported a small Reynolds number simulation using front-tracking and finite difference methods that displayed a resonance phenomenon with varying interfacial tension and frequency. For a viscoelastic drop with a UCM constitutive relation we found that the drop dynamics changed character significantly, in that the deformation varies non-monotonically with relaxation time. Finally, we found that elasticity generates a system of shear waves that affects the deformation. We will present a perturbative analysis of the wave phenomenon. The effect will be explained with the help of a simple demonstrative example of a layer of viscoelatic fluid underlying another layer of viscous fluid. The importance of the phenomenon in different situations will be investigated.

  9. Do Bacterial Symbionts Govern Aphid's Dropping Behavior?

    PubMed

    Lavy, Omer; Sher, Noa; Malik, Assaf; Chiel, Elad

    2015-06-01

    Defensive symbiosis is amongst nature's most important interactions shaping the ecology and evolution of all partners involved. The pea aphid, Acyrthosiphon pisum Harris (Hemiptera: Aphididae), harbors one obligatory bacterial symbiont and up to seven different facultative symbionts, some of which are known to protect the aphid from pathogens, natural enemies, and other mortality factors. Pea aphids typically drop off the plant when a mammalian herbivore approaches it to avoid incidental predation. Here, we examined whether bacterial symbionts govern the pea aphid dropping behavior by comparing the bacterial fauna in dropping and nondropping aphids of two A. pisum populations, using two molecular techniques: high-throughput profiling of community structure using 16 S reads sequenced on the Illumina platform, and diagnostic polymerase chain reaction (PCR). We found that in addition to the obligatory symbiont, Buchnera aphidicola, the tested colonies of A. pisum harbored the facultative symbionts Serratia symbiotica, Regiella insecticola and Rickettsia, with no significant differences in infection proportions between dropping and nondropping aphids. While S. symbiotica was detected by both techniques, R. insecticola and Rickettsia could be detected only by diagnostic PCR. We therefore conclude that A. pisum's dropping behavior is not affected by its bacterial symbionts and is possibly affected by other factors. PMID:26313964

  10. Drops with non-circular footprints

    NASA Astrophysics Data System (ADS)

    Ravazzoli, Pablo D.; González, Alejandro G.; Diez, Javier A.

    2016-04-01

    In this paper we study the morphology of drops formed on partially wetting substrates, whose footprint is not circular. These drops are consequence of the breakup processes occurring in thin films when anisotropic contact line motions take place. The anisotropy is basically due to the hysteresis of the contact angle since there is a wetting process in some parts of the contact line, while a dewetting occurs in other parts. Here, we obtain a characteristic drop shape from the rupture of a long liquid filament sitting on a solid substrate. We analyze its shape and contact angles by means of goniometric and refractive techniques. We also find a non-trivial steady state solution for the drop shape within the long wave approximation (lubrication theory), and we compare most of its features with experimental data. This solution is presented both in Cartesian and polar coordinates, whose constants must be determined by a certain group of measured parameters. Besides, we obtain the dynamics of the drop generation from numerical simulations of the full Navier-Stokes equation, where we emulate the hysteretic effects with an appropriate spatial distribution of the static contact angle over the substrate.

  11. Drop deployment system for crystal growth apparatus

    NASA Technical Reports Server (NTRS)

    Rhodes, Percy H. (Inventor); Snyder, Robert S. (Inventor); Pusey, Marc L. (Inventor)

    1992-01-01

    This invention relates to a crystal growth apparatus (10) generally used for growing protein crystals wherein a vapor diffusion method is used for growing the crystals. In this apparatus, a precipitating solution and a solution containing dissolved crystalline material are stored in separate vials (12, 14), each having a resilient diaphragm (28) across one end and an opening (24) with a puncturable septum (26) thereacross at an opposite end. The vials are placed in receptacles (30) having a manifold (41) with a manifold diaphragm (42) in contact with the vial diaphragm at one end of the receptacle and a hollow needle (36) for puncturing the septum at the other end of the manifold. The needles of each vial communicate with a ball mixer (40) that mixes the precipitate and protein solutions and directs the mixed solution to a drop support (64) disposed in a crystal growth chamber (16), the drop support being a tube with an inner bevelled surface (66) that provides more support for the drop (68) than the tubes of the prior art. A sealable storage region (70) intermediate the drop support and mixer provides storage of the drop (68) and the grown crystals.

  12. 36 CFR 1230.10 - Who is responsible for preventing the unlawful or accidental removal, defacing, alteration, or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... preventing the unlawful or accidental removal, defacing, alteration, or destruction of records? 1230.10... responsible for preventing the unlawful or accidental removal, defacing, alteration, or destruction of records? The heads of Federal agencies must: (a) Prevent the unlawful or accidental removal,...

  13. Monitoring Volcanoes by Use of Air-Dropped Sensor Packages

    NASA Technical Reports Server (NTRS)

    Kedar, Sharon; Rivellini, Tommaso; Webb, Frank; Blaes, Brent; Bracho, Caroline; Lockhart, Andrew; McGee, Ken

    2003-01-01

    Sensor packages that would be dropped from airplanes have been proposed for pre-eruption monitoring of physical conditions on the flanks of awakening volcanoes. The purpose of such monitoring is to gather data that could contribute to understanding and prediction of the evolution of volcanic systems. Each sensor package, denoted a volcano monitoring system (VMS), would include a housing with a parachute attached at its upper end and a crushable foam impact absorber at its lower end (see figure). The housing would contain survivable low-power instrumentation that would include a Global Positioning System (GPS) receiver, an inclinometer, a seismometer, a barometer, a thermometer, and CO2 and SO2 analyzers. The housing would also contain battery power, control, data-logging, and telecommunication subsystems. The proposal for the development of the VMS calls for the use of commercially available sensor, power, and telecommunication equipment, so that efforts could be focused on integrating all of the equipment into a system that could survive impact and operate thereafter for 30 days, transmitting data on the pre-eruptive state of a target volcano to a monitoring center. In a typical scenario, VMSs would be dropped at strategically chosen locations on the flanks of a volcano once the volcano had been identified as posing a hazard from any of a variety of observations that could include eyewitness reports, scientific observations from positions on the ground, synthetic-aperture-radar scans from aircraft, and/or remote sensing from aboard spacecraft. Once dropped, the VMSs would be operated as a network of in situ sensors that would transmit data to a local monitoring center. This network would provide observations as part of an integrated volcano-hazard assessment strategy that would involve both remote sensing and timely observations from the in situ sensors. A similar strategy that involves the use of portable sensors (but not dropping of sensors from aircraft) is already in use in the Volcano Disaster Assistance Program (VDAP), which was developed by the U.S. Geological Survey and the U.S. Office of Foreign Disaster Assistance to respond to volcanic crises around the world. The VMSs would add a greatly needed capability that would enable VDAP response teams to deploy their volcano-monitoring equipment in a more timely manner with less risk to personnel in the field.

  14. Severe Nuclear Accident Program (SNAP) - a real time model for accidental releases

    SciTech Connect

    Saltbones, J.; Foss, A.; Bartnicki, J.

    1996-12-31

    The model: Several Nuclear Accident Program (SNAP) has been developed at the Norwegian Meteorological Institute (DNMI) in Oslo to provide decision makers and Government officials with real-time tool for simulating large accidental releases of radioactivity from nuclear power plants or other sources. SNAP is developed in the Lagrangian framework in which atmospheric transport of radioactive pollutants is simulated by emitting a large number of particles from the source. The main advantage of the Lagrangian approach is a possibility of precise parameterization of advection processes, especially close to the source. SNAP can be used to predict the transport and deposition of a radioactive cloud in e future (up to 48 hours, in the present version) or to analyze the behavior of the cloud in the past. It is also possible to run the model in the mixed mode (partly analysis and partly forecast). In the routine run we assume unit (1 g s{sup -1}) emission in each of three classes. This assumption is very convenient for the main user of the model output in case of emergency: Norwegian Radiation Protection Agency. Due to linearity of the model equations, user can test different emission scenarios as a post processing task by assigning different weights to concentration and deposition fields corresponding to each of three emission classes. SNAP is fully operational and can be run by the meteorologist on duty at any time. The output from SNAP has two forms: First on the maps of Europe, or selected parts of Europe, individual particles are shown during the simulation period. Second, immediately after the simulation, concentration/deposition fields can be shown every three hours of the simulation period as isoline maps for each emission class. In addition, concentration and deposition maps, as well as some meteorological data, are stored on a public accessible disk for further processing by the model users.

  15. Atmospheric dispersion of ammonia accidentally released from the 242-A Evaporator, Hanford Site, Richland, Washington

    SciTech Connect

    Daling, P.M.; Lavender, J.C.

    1997-11-01

    Two errors have been identified in the authorization basis for the 242-A Evaporator at the Hanford Site. These errors, which appear in the 242-A Evaporator/Crystallizer Final Safety Analysis Report analysis of ammonia gas concentrations accidentally released from the 242-A Evaporator, are: (1) the vessel ventilation system flow rate used in the previous calculations is a factor of ten higher than the actual flow rate, and (2) the previous calculations did not account for the ammonia source term reduction that would occur via condensation of ammonia vapors, which will remove a large fraction of the ammonia from the exhaust gas stream. The purpose of this document is to correct these errors and recalculate the maximum ground-level concentrations of ammonia released to the environment as a result of potential errors in blending Evaporator feed. The errors offset each other somewhat, so it is unlikely that the 242-A Evaporator has operated outside its current authorization basis. However, the errors must be corrected and the results incorporated into a revision of the 242-A Evaporator/Crystallizer Safety Analysis Report, WHC-SD-WM-SAR-023. An EPA-approved atmospheric dispersion model, SCREEN3, was used to recalculate the maximum ground-level concentrations of ammonia that would be released from the 242-A Evaporator as a result of a feed-blending error. The results of the re-analysis of the 242-A Evaporator`s ammonia release scenario are as follows. The onsite receptor 100 m away from the release point (242-A vessel vent stack) is projected to be exposed to a maximum ground-level concentration of ammonia of 8.3 ppm. The maximally-exposed offsite receptor, located at the nearest Hanford Site boundary 16 km away from the 242-A vessel vent stack, will be exposed to a maximum ground-level concentration of 0.11 ppm ammonia.

  16. Dropping In a Microgravity Environment (DIME) Contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Meredith Mendenhall of Sycamore High School, Cincinnati, Ohio, flips on a tape recorder in preparation for a drop. This image is from a digital still camera; higher resolution is not available.

  17. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Here, students are briefed by NASA engineer Daniel Dietrich at the top of the drop tower. This image is from a digital still camera; higher resolution is not available.

  18. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Here Jose Carrion, a lab mechanic with AKAC, starts the orange-colored drag shield, and the experiment apparatus inside, on the hoist upward to the control station at the top of the drop tower. This image is from a digital still camera; higher resolution is not available.

  19. Dropping In a Microgravity Environment (DIME) Contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Sandi Thompson of the National Center for Microgravity Research GRC makes a final adjustment to the drop package. This image is from a digital still camera; higher resolution is not available.

  20. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Here students from Sycamore High School in Cincinnati, Ohio, talk with Dr. Dennis Stocker, one of Glenn's lead microgravity scientists, about the uses of the drop tower. This image is from a digital still camera; higher resolution is not available.

  1. Ultrasonic characterization of single drops of liquids

    DOEpatents

    Sinha, Dipen N.

    1998-01-01

    Ultrasonic characterization of single drops of liquids. The present invention includes the use of two closely spaced transducers, or one transducer and a closely spaced reflector plate, to form an interferometer suitable for ultrasonic characterization of droplet-size and smaller samples without the need for a container. The droplet is held between the interferometer elements, whose distance apart may be adjusted, by surface tension. The surfaces of the interferometer elements may be readily cleansed by a stream of solvent followed by purified air when it is desired to change samples. A single drop of liquid is sufficient for high-quality measurement. Examples of samples which may be investigated using the apparatus and method of the present invention include biological specimens (tear drops; blood and other body fluid samples; samples from tumors, tissues, and organs; secretions from tissues and organs; snake and bee venom, etc.) for diagnostic evaluation, samples in forensic investigations, and detection of drugs in small quantities.

  2. Drop impact on a flexible fiber.

    PubMed

    Dressaire, Emilie; Sauret, Alban; Boulogne, Franois; Stone, Howard A

    2015-12-16

    When droplets impact fibrous media, the liquid can be captured by the fibers or contact then break away. Previous studies have shown that the efficiency of drop capture by a rigid fiber depends on the impact velocity and a threshold velocity was defined below which the drop is captured. However, it is necessary to consider the coupling of elastic and capillary effects to achieve an improved understanding of the capture process for soft substrates. Here, we study experimentally the dynamics of a single drop impacting on a thin flexible fiber. Our results demonstrate that the threshold capture velocity depends on the flexibility of fibers in a non-monotonic way. We conclude that tuning the mechanical properties of fibers can optimize the efficiency of droplet capture. PMID:26458218

  3. Nonreciprocal photonic crystal add-drop filter

    SciTech Connect

    Tao, Keyu; Xiao, Jun-Jun; Yin, Xiaobo

    2014-11-24

    We present a versatile add-drop integrated photonic filter (ADF) consisting of nonreciprocal waveguides in which the propagation of light is restricted in one predetermined direction. With the bus and add/drop waveguides symmetrically coupled through a cavity, the four-port device allows each individual port to add and/or drop a signal of the same frequency. The scheme is general and we demonstrate the nonreciprocal ADF with magneto-optical photonic crystals. The filter is immune to waveguide defects, allowing straightforward implementation of multi-channel ADFs by cascading the four-port designs. The results should find applications in wavelength-division multiplexing and related integrated photonic techniques.

  4. Thermocapillary Convection in Bubbles and Drops

    NASA Technical Reports Server (NTRS)

    Balassubramaniam; Subramanian, R. Shankar

    2003-01-01

    When bubbles or drops are present in an immiscible liquid in reduced gravity and the temperature of the liquid is non-uniform, a thermocapillary stress is generated at the interface due to the variation of interfacial tension with temperature. The resulting flow propels the drop freely suspended in the liquid towards warmer regions, so as to minimize the interfacial energy. In this presentation, we will focus on the effect of convective transport of momentum and energy, that are characterized by the Reynolds number and the Marangoni number, respectively. The results of asymptotic analyses for the speed of the drop for low and large values of these parameters will be discussed. These predictions as well as those from numerical simulations will be compared with reduced gravity experimental results obtained from experiments performed aboard the space shuttle.

  5. Computer simulations of nematic drops: Coupling between drop shape and nematic order

    NASA Astrophysics Data System (ADS)

    Rull, L. F.; Romero-Enrique, J. M.; Fernandez-Nieves, A.

    2012-07-01

    We perform Monte Carlo computer simulations of nematic drops in equilibrium with their vapor using a Gay-Berne interaction between the rod-like molecules. To generate the drops, we initially perform NPT simulations close to the nematic-vapor coexistence region, allow the system to equilibrate and subsequently induce a sudden volume expansion, followed with NVT simulations. The resultant drops coexist with their vapor and are generally not spherical but elongated, have the rod-like particles tangentially aligned at the surface and an overall nematic orientation along the main axis of the drop. We find that the drop eccentricity increases with increasing molecular elongation, κ. For small κ the nematic texture in the drop is bipolar with two surface defects, or boojums, maximizing their distance along this same axis. For sufficiently high κ, the shape of the drop becomes singular in the vicinity of the defects, and there is a crossover to an almost homogeneous texture; this reflects a transition from a spheroidal to a spindle-like drop.

  6. Instrumented drop ball tester for percussion primers

    NASA Astrophysics Data System (ADS)

    Woods, C. M.; Robinson, M. A.; Merten, C. W.; Robbins, V. E.; Begeal, D. R.

    The drop ball tester has historically been used for determining the threshold characteristics of percussion primers. Typically, the data obtained from such a tester show a wide variation with significantly large standard deviations. This requires that the acceptance specifications for primers be fairly lax. To determine how much of the data scatter was due to the tester alone, a drop ball tester was instrumented with a force monitoring gage, velocity capabilities, deflection gages, and a pressure time output measuring system. This paper deals with the basic fundamental physics involved with the tester and presents results of improvements to the tester geometry. Threshold test results are presented, correlating all of the variables measured.

  7. Statistical Model of Evaporating Multicomponent Fuel Drops

    NASA Technical Reports Server (NTRS)

    Harstad, Kenneth; LeClercq, Patrick; Bellan, Josette

    2007-01-01

    An improved statistical model has been developed to describe the chemical composition of an evaporating multicomponent- liquid drop and of the mixture of gases surrounding the drop. The model is intended for use in computational simulations of the evaporation and combustion of sprayed liquid fuels, which are typically mixtures of as many as hundreds of different hydrocarbon compounds. The present statistical model is an approximation designed to afford results that are accurate enough to contribute to understanding of the simulated physical and chemical phenomena, without imposing an unduly large computational burden.

  8. A Digital Observer For Impact Drop Compensation

    NASA Astrophysics Data System (ADS)

    Umida, Hidetoshi; Ohara, Masaki

    1987-01-01

    A high performance load torque observer for impact drop compensation of a motor drive system has been realized by using a digital signal processor (DSP). This observer unit realizes high speed response and low noise characteristics by the DSP's software. The software is constructed with three functions; An improved load torque observer for high speed estimation, a moving average filter for eliminating torque pulsation component caused by inequality in firing angles of converter arms, and a variable filter for reducing noise contained in the estimated load torque. Use of this observer unit with a motor drive system offers high stability and impact drop compensation effect.

  9. The new Drop Tower catapult system

    NASA Astrophysics Data System (ADS)

    von Kampen, Peter; Kaczmarczik, Ulrich; Rath, Hans J.

    2006-07-01

    The Center of Applied Space Technology and Microgravity (ZARM) was founded in 1985 as an institute of the University Bremen, which focuses on research on gravitational and space-related phenomena. In 1988, the construction of the "Drop Tower" began. Since then, the eye-catching tower with a height of 146 m and its characteristic glass roof has become the emblem of the technology centre in Bremen. The Drop Tower Bremen provides a facility for experiments under conditions of weightlessness. Items are considered weightless, when they are in "free fall", i.e. moving without propulsion within the gravity field of the earth. The height of the tower limits the simple "free fall" experiment period to max. 4.74 s. With the inauguration of the catapult system in December 2004, the ZARM is entering a new dimension. This world novelty will meet scientists' demands of extending the experiment period up to 9.5 s. Since turning the first sod on May 3rd, 1988, the later installation of the catapult system has been taken into account by building the necessary chamber under the tower. The catapult system is located in a chamber 10 m below the base of the tower. This chamber is almost completely occupied by 12 huge pressure tanks. These tanks are placed around the elongation of the vacuum chamber of the drop tube. In its centre there is the pneumatic piston that accelerates the drop capsule by the pressure difference between the vacuum inside the drop tube and the pressure inside the tanks. The acceleration level is adjusted by means of a servo hydraulic breaking system controlling the piston velocity. After only a quarter of a second the drop capsule achieves its lift-off speed of 175 km/h. With this exact speed, the capsule will rise up to the top of the tower and afterwards fall down again into the deceleration unit which has been moved under the drop tube in the meantime. The scientific advantages of the doubled experiment time are obvious: during almost 10 s of high-quality weightlessness the range of compatible experiments amplifies even more and researchers can observe processes for a longer period of time. Thus, the new earth-bound laboratory of the ZARM offers unique conditions for scientific research. Moreover, it increases the attractiveness of the Drop Tower and contributes an important part to the establishment of the Bremen as an international centre for space technology.

  10. Millikan "oil drop" stabilized by growth.

    PubMed

    Sun, L K; Gertler, A W; Reiss, H

    1979-01-26

    A diffusion cloud chamber has been used to qualitatively study some dynamic properties of liquid drops by suspending them in an electric field at the plane of saturation (p/ps = 1, where p is the actual partial pressure of the vapor at a given elevation and ps is the equilibrium pressure at that temperature characteristic of that elevation). By varying the strength of the electric field, it is possible to change the size of the suspended droplets and even, if desired, to isolate a single drop. PMID:17772443

  11. Water Drops Dancing on Ice: How Sublimation Leads to Drop Rebound

    NASA Astrophysics Data System (ADS)

    Antonini, C.; Bernagozzi, I.; Jung, S.; Poulikakos, D.; Marengo, M.

    2013-07-01

    Drop rebound is a spectacular event that appears after impact on hydrophobic or superhydrophobic surfaces but can also be induced through the so-called Leidenfrost effect. Here we demonstrate that drop rebound can also originate from another physical phenomenon, the solid substrate sublimation. Through drop impact experiments on a superhydrophobic surfaces, a hot plate, and solid carbon dioxide (commonly known as dry ice), we compare drop rebound based on three different physical mechanisms, which apparently share nothing in common (superhydrophobicity, evaporation, and sublimation), but lead to the same rebound phenomenon in an extremely wide temperature range, from 300C down to even below -79C. The formation and unprecedented visualization of an air vortex ring around an impacting drop are also reported.

  12. Effects of subcooling and rod drop speed on the BWR rod drop accident

    SciTech Connect

    Cokinos, D.; Carew, J.; Aronson, A.

    1982-01-01

    The techniques and models used in the analysis of the control rod drop accident (CRDA) in a BWR have ranged from approximate conservative methods with a simple feedback model to detailed representations of the thermal-hydraulic and neutronic mechanisms. In a recent paper Cheng and Diamond presented a detailed evaluation of the CRDA and the effects of varying a number of important accident parameters. Their calculations performed with the BNL-TWIGL core dynamics code, have shown that the effect of inlet subcooling and rod drop speed play an important role in determining the severity of the rod drop accident. The purpose of the work summarized in this paper has been to determine in detail the dependence of the rod drop accident parameters on the (1) inlet subcooling; and (2) rod drop speed.

  13. Extracorporeal Rewarming From Accidental Hypothermia of Patient With Suspected Trauma

    PubMed Central

    Darocha, Tomasz; Kosiński, Sylweriusz; Jarosz, Anna; Drwila, Rafal

    2015-01-01

    Abstract The use of extracorporeal membrane oxygenation is a new approach to rewarming patients with severe hypothermia and hemodynamic instability. There are, however, many questions regarding qualification for this technique in case of suspected or confirmed trauma. A male with confirmed accidental hypothermia (25°C) and after successful cardiopulmonary resuscitation from in-hospital cardiac arrest was subjected to a protocol of extracorporeal rewarming from profound hypothermia. Because of unclear history, a full trauma computed tomography was performed that showed pericerebral hematoma and signs of previously undergone right craniotomy, multiple right-sided rib fractures and the presence of intraperitoneal fluid. Based on repeated imaging and specialist consultation, no life-threatening injuries were identified and rewarming with extracorporeal membrane oxygenation was safely performed. In a year follow-up, the patient was found to be alive, with no neurologic deficits. Although this case highlights the first successful utilization of extracorporeal rewarming in a trauma patient at our center there are several limitations to its widespread use PMID:26166091

  14. High mortality due to accidental salinomycin intoxication in sheep.

    PubMed

    Ashrafihelan, Javad; Eisapour, Hamed; Erfani, Amir Mehdi; Kalantary, Amir Ali; Amoli, Jamileh Salar; Mozafari, Morteza

    2014-09-01

    In February 2012, 100% mortality was reported in a herd with 79 local sheep that were kept around of Abhar, Northwest of Iran. The ration for adult sheep was daily mixed (40 kg straw, 25 kg wheat and 2 kg Vit-C premix) and accidentally 1 500 g of salinomycin (Salinomycin 12% Premix; Aras Bazar Laboratories, Iran) had been added to the ration (22388 mg/kg = 22388 ppm) and overnight was fed to herd. At the morning, 78 sheep were founded dead and one of them showed convulsive seizures. Postmortem examination revealed pulmonary congestion and edema, hemorrhages in abomasum, large pale kidney and white streak lines in myocardium. Main histopathologic lesions were extensive subepicardial and intercardiomyofibers hemorrhages, extensive cardiomyolysis and myocarditis in heart, severe hyperemia and extensive acute tubular necrosis (ATN) in kidneys and focal necrosis and retention of bile cholangitis in the liver. In this study, on the basis of the history, observation of the ionophore remnant in the ration, clinical signs, gross and histopathological findings, acute salinomycin intoxication is definitely diagnosed. PMID:26109896

  15. Inverse Modeling of Accidental Releases of Atmospheric Pollutants: New Developments.

    NASA Astrophysics Data System (ADS)

    Bocquet, M.

    2007-12-01

    An account is given on new data assimilation techniques that have recently been used to identify the source of an accidental release of pollutant into the atmosphere, and forecast (possibly in real time) the subsequent dispersion plume. It could be a chemical cloud from an industrial site or a release of radionuclides from a nuclear power plant (from minor accident to core meltdown). These methods are not necessarily based on Gaussian hypotheses, for instance the source may be given as positive or bounded. In particular, the usual least squares cost function (4D-Var) is replaced with purposely devised functionals that are not necessarily quadratic. These methods have been applied successfully to the reconstruction of the Chernobyl accident, the Algeciras incident or the ETEX experiment, and outperform previous approaches. As far as state assimilation is concerned, the techniques have been applied a posteriori to the reconstruction of the ETEX plume, after all observations are acquired. The method has also been applied to the reconstruction of the dispersion plume, in the context of an emergency situation: the data have been assimilated sequentially as they arrived and a forecast is performed after each analysis. This provides with a picture of what could be achieved (forecast, risk assessment) in case of a real emergency with a Chemistry Transport Model and advanced data assimilation techniques. A second-order sensitivity study that applies to the possibly non- quadratic cost functions has also been carried out in the context of these reconstructions.

  16. Mitigation of Lung Injury after Accidental Exposure to Radiation

    PubMed Central

    Mahmood, J.; Jelveh, S.; Calveley, V.; Zaidi, A.; Doctrow, S. R.; Hill, R. P.

    2011-01-01

    There is a serious need to develop effective mitigators against accidental radiation exposures. In radiation accidents, many people may receive nonuniform whole-body or partial-body irradiation. The lung is one of the more radiosensitive organs, demonstrating pneumonitis and fibrosis that are believed to develop at least partially because of radiation-induced chronic inflammation. Here we addressed the crucial questions of how damage to the lung can be mitigated and whether the response is affected by irradiation to the rest of the body. We examined the widely used dietary supplement genistein given at two dietary levels (750 or 3750 mg/kg) to Fischer rats irradiated with 12 Gy to the lung or 8 Gy to the lung + 4 Gy to the whole body excluding the head and tail (whole torso). We found that genistein had promising mitigating effects on oxidative damage, pneumonitis and fibrosis even at late times (36 weeks) when drug treatment was initiated 1 week after irradiation and stopped at 28 weeks postirradiation. The higher dose of genistein showed no greater beneficial effect. Combined lung and whole-torso irradiation caused more lung-related severe morbidity resulting in euthanasia of the animals than lung irradiation alone. PMID:22013884

  17. High mortality due to accidental salinomycin intoxication in sheep

    PubMed Central

    Eisapour, Hamed; Erfani, Amir Mehdi; Kalantary, Amir Ali; Amoli, Jamileh Salar; Mozafari, Morteza

    2014-01-01

    In February 2012, 100% mortality was reported in a herd with 79 local sheep that were kept around of Abhar, Northwest of Iran. The ration for adult sheep was daily mixed (40 kg straw, 25 kg wheat and 2 kg Vit-C premix) and accidentally 1 500 g of salinomycin (Salinomycin 12% Premix; Aras Bazar Laboratories, Iran) had been added to the ration (22388 mg/kg = 22388 ppm) and overnight was fed to herd. At the morning, 78 sheep were founded dead and one of them showed convulsive seizures. Postmortem examination revealed pulmonary congestion and edema, hemorrhages in abomasum, large pale kidney and white streak lines in myocardium. Main histopathologic lesions were extensive subepicardial and intercardiomyofibers hemorrhages, extensive cardiomyolysis and myocarditis in heart, severe hyperemia and extensive acute tubular necrosis (ATN) in kidneys and focal necrosis and retention of bile cholangitis in the liver. In this study, on the basis of the history, observation of the ionophore remnant in the ration, clinical signs, gross and histopathological findings, acute salinomycin intoxication is definitely diagnosed. PMID:26109896

  18. Comparative toxicology of intentional and accidental heroin overdose.

    PubMed

    Darke, Shane; Duflou, Johan; Torok, Michelle

    2010-07-01

    The demographic and toxicological characteristics of deliberate (SUI, n = 50) and accidental (ACC, n = 927) fatal heroin overdose cases were examined. SUI cases were more likely to be female, had lower body mass indices, were more likely to be enrolled in treatment and less likely to have hepatic pathology. The median blood morphine concentration of SUI cases was significantly higher than that of ACC cases (0.70 vs. 0.40 mg/L, p < 0.001). Blood morphine concentrations of >1 mg/L were seen among 38.0% of SUI cases compared to 13.9% of ACC cases. Being a member of the SUI group remained a significant independent predictor of higher morphine concentrations after controlling for the effects of potential confounders (p < 0.001), other significant predictors being the absence of alcohol (p < 0.001), the presence of methadone (p < 0.05), and the presence of cocaine (p < 0.05). The current data are consistent with the view that suicide forms a small, but distinct, category of heroin overdose cases, rather than overdose being a parasuicidal phenomenon per se. PMID:20384920

  19. Including fathers in preventing non-accidental head injury.

    PubMed

    Coles, Lisa; Collins, Lynne

    2009-04-01

    Health visitors identified fathers as a marginalised, difficult-to-reach group when aiming for universal implementation of a public health programme to prevent non-accidental head injury (NAHI) in babies. Follow-on research with 30 fathers from disadvantaged backgrounds, including some in prison, explored barriers and facilitating factors to preventing NAHI through focus groups and interviews. Fathers expressed both responsibility and helplessness in managing a baby, but many felt excluded from gaining skills and knowledge by healthcare staff. Barriers to implementing a prevention programme included a lack of knowledge about head injuries in babies and poor understanding of prevention as a reduction of risk factors. Fear of blame for a head injury could lead to injury concealment, indicating a taboo subject. Facilitators for fathers to learn about preventing head injuries in babies included concerns of their masculinity being at odds with the frailty of the newborn, recognition of fathers' needs to be valued in their own right, and a need for individualised plans for gaining information and increasing confidence. The modifiable barriers to prevention, from the fathers' perspectives, add to the theoretical and applied evidence base for the prevention of NAHI. PMID:19397079

  20. Non-accidental health impacts of wildfire smoke.

    PubMed

    Youssouf, Hassani; Liousse, Catherine; Roblou, Laurent; Assamoi, Eric-Michel; Salonen, Raimo O; Maesano, Cara; Banerjee, Soutrik; Annesi-Maesano, Isabella

    2014-11-01

    Wildfires take a heavy toll on human health worldwide. Climate change may increase the risk of wildfire frequency. Therefore, in view of adapted preventive actions, there is an urgent need to further understand the health effects and public awareness of wildfires. We conducted a systematic review of non-accidental health impacts of wildfire and incorporated lessons learned from recent experiences. Based on the literature, various studies have established the relationship between one of the major components of wildfire, particulate matter (particles with diameter less than 10 m (PM10) and less than 2.5 m (PM2.5)) and cardiorespiratory symptoms in terms of Emergency Rooms visits and hospital admissions. Associations between wildfire emissions and various subclinical effects have also been established. However, few relationships between wildfire emissions and mortality have been observed. Certain segments of the population may be particularly vulnerable to smoke-related health risks. Among them, people with pre-existing cardiopulmonary conditions, the elderly, smokers and, for professional reasons, firefighters. Potential action mechanisms have been highlighted. Overall, more research is needed to better understand health impact of wildfire exposure. PMID:25405597

  1. Assessment of accidental intakes of uranyl acetylacetonate (UAA)

    SciTech Connect

    Fisher, D.R.; Briant, J.K.

    1993-12-01

    Uranyl acetylacetonate (UAA) is an organic complex of uranium used for military applications as a chemical catalyst in high explosives. It is prepared from depleted uranium metal (in lots of 5 kg to 7 kg) by dissolution in nitric acid, neutralization, and complexation with 2,4-pentanedione; the precipitate is dissolved in benzene and recrystallized, dried, ground, and packaged. About six workers at a small chemical company were exposed over a period of time to UAA powders during routine preparation and packaging of the uranium catalyst. The dissolution characteristics of the inhaled material were unknown and could not be determined from the published scientific literature. A 1.05-g sample of UAA powder was obtained from the responsible regulatory authority for further study to determine its chemical composition, and for dissolution in simulated lung fluid. We found the solubility of UAA to be equivalent to a mixture of 52% ICRP class D and 48% ICRP class W material. The annual limit on intake and the derived air concentration for radiological protection were estimated from this result for airborne exposure to UAA. A recycling biokinetic model was used to estimate both material-specific variations in urinary excretion rates and lung retention with time after accidental intakes. This study provides new information for evaluating future exposures to UAA.

  2. Accidental inhalation of mercury vapour: respiratory and toxicologic consequences.

    PubMed Central

    Lien, D. C.; Todoruk, D. N.; Rajani, H. R.; Cook, D. A.; Herbert, F. A.

    1983-01-01

    Four adults, including a pregnant woman, and three children were admitted to hospital following accidental exposure to mercury vapour produced by heating mercury-gold amalgam. Initial symptoms and signs included a paroxysmal cough, dyspnea, chest pain, tachypnea, nausea, vomiting, fever and leukocytosis. Pulmonary function testing performed on the second day after exposure revealed air-flow obstruction and minor restrictive defects in three patients. The diffusing capacity of the lung for carbon monoxide was reduced in two of these patients. The mean initial blood mercury level (+/- one standard deviation) for the seven patients was 30.8 +/- 1.5 micrograms/dl. A computer analysis showed mercury to behave as a two-compartment system, the compartments having half-lives of 2 and 8 days. The four adults received chelation therapy with D-penicillamine, which did not affect the urinary excretion of mercury. The pregnant woman's infant, born 26 days after exposure, had no detectable clinical abnormalities. The levels of mercury in the blood of the mother and infant at birth and 6 days later were comparable, indicating free transfer of the metal across the placenta. Images FIG. 1 FIG. 2 PMID:6883261

  3. Extracorporeal Rewarming From Accidental Hypothermia of Patient With Suspected Trauma.

    PubMed

    Darocha, Tomasz; Kosiński, Sylweriusz; Jarosz, Anna; Drwila, Rafal

    2015-07-01

    The use of extracorporeal membrane oxygenation is a new approach to rewarming patients with severe hypothermia and hemodynamic instability. There are, however, many questions regarding qualification for this technique in case of suspected or confirmed trauma.A male with confirmed accidental hypothermia (25°C) and after successful cardiopulmonary resuscitation from in-hospital cardiac arrest was subjected to a protocol of extracorporeal rewarming from profound hypothermia. Because of unclear history, a full trauma computed tomography was performed that showed pericerebral hematoma and signs of previously undergone right craniotomy, multiple right-sided rib fractures and the presence of intraperitoneal fluid. Based on repeated imaging and specialist consultation, no life-threatening injuries were identified and rewarming with extracorporeal membrane oxygenation was safely performed. In a year follow-up, the patient was found to be alive, with no neurologic deficits.Although this case highlights the first successful utilization of extracorporeal rewarming in a trauma patient at our center there are several limitations to its widespread use. PMID:26166091

  4. Non-Accidental Health Impacts of Wildfire Smoke

    PubMed Central

    Youssouf, Hassani; Liousse, Catherine; Roblou, Laurent; Assamoi, Eric-Michel; Salonen, Raimo O.; Maesano, Cara; Banerjee, Soutrik; Annesi-Maesano, Isabella

    2014-01-01

    Wildfires take a heavy toll on human health worldwide. Climate change may increase the risk of wildfire frequency. Therefore, in view of adapted preventive actions, there is an urgent need to further understand the health effects and public awareness of wildfires. We conducted a systematic review of non-accidental health impacts of wildfire and incorporated lessons learned from recent experiences. Based on the literature, various studies have established the relationship between one of the major components of wildfire, particulate matter (particles with diameter less than 10 µm (PM10) and less than 2.5 µm (PM2.5)) and cardiorespiratory symptoms in terms of Emergency Rooms visits and hospital admissions. Associations between wildfire emissions and various subclinical effects have also been established. However, few relationships between wildfire emissions and mortality have been observed. Certain segments of the population may be particularly vulnerable to smoke-related health risks. Among them, people with pre-existing cardiopulmonary conditions, the elderly, smokers and, for professional reasons, firefighters. Potential action mechanisms have been highlighted. Overall, more research is needed to better understand health impact of wildfire exposure. PMID:25405597

  5. Prolonged Toxic Encephalopathy following Accidental 4-Aminopyridine Overdose

    PubMed Central

    Ballesta Méndez, Maria; van Pesch, Vincent; Capron, Arnaud; Hantson, Philippe

    2014-01-01

    Background. 4-Aminopyridine (4-AP) is a drug that is used to improve motor fatigue in patients suffering from multiple sclerosis (MS). Medication error can occur, as commercial preparation may not be available in some countries. Case Presentation. A 58-year-old woman with progressive MS presented with status epilepticus. She was receiving 4-AP for more than 3 years. The symptoms started soon after the ingestion of a single pill that was supposed to contain 10 mg 4-AP, but further investigations revealed that each pill had been inadvertently prepared with an 100 mg 4-AP concentration. The patient was admitted to the intensive care unit (ICU) for appropriate management (orotracheal intubation, sedation, and antiepileptic drugs). The first electroencephalogram (EEG) showed abundant irregular spike-waves on the left central regions. Neurological condition gradually improved from day 7, while the EEG did not reveal any more electrical seizures but was still consistent with toxic encephalopathy. The patient stayed in the ICU until day 13. At discharge from the rehabilitation ward (2.5 months later), the patient had not yet recovered her previous cognitive and functional condition. Conclusion. A single 100 mg 4-AP accidental overdose may cause serious immediate complications, with a slow and incomplete neurological recovery. PMID:24822136

  6. Reduction in drop size of ophthalmic topical drop preparations and the impact of treatment.

    PubMed

    Kumar, Shiva; Karki, Roopa; Meena, Marreddy; Prakash, Tigari; Rajeswari, Tanniru; Goli, Divakar

    2011-07-01

    In this work we devised a method to create smaller eye drops of the glaucoma medication timolol maleate by altering the dropper tip design and changing the physical properties of the formulation. Most ocular diseases are treated with topical application of eye drops. After instillation of an eye drop, typically, less than 5% of the applied drug penetrates the cornea and reaches the intraocular tissues; the major fraction of the instilled drug is absorbed and enters the systemic circulation. Ophthalmic solutions are available in multidose or single-dose glass/plastic dropper bottles that deliver drops with a volume that ranges from 25 μL to 70 μL (average 40 μL). Because of the low capacity of the precorneal area, the optimal drop volume is about 20 μL; with larger volumes there is the risk of adverse systemic effects due to absorption of the drug via the nasal mucosa. Thus, both from the biopharmaceutical and economic point of view, drops of only 5-15 mL volume should be instilled into the eye. In this present work we devised a method to reduce the size of the drop by inserting a glass capillary tube into the dropper tip and by changing the physical properties of the formulation (by altering the concentration of Tween 80™, i.e., 0.05% and 0.1% of Tween 80™). We measured the drop sizes of the different timolol eye drop formulations available in the market and estimated the yearly cost of the medications. Our timolol maleate formulation with 0.1% concentration of Tween 80™ delivered through the dropper tip with the inserted glass capillary was shown to be better than the other formulations available in the market in terms of ability to deliver smaller drops, meaning that each bottle would last longer and that the yearly cost of treatment would be lower. PMID:22171317

  7. 14 CFR 23.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Construction Landing Gear § 23.727 Reserve energy absorption drop test. (a) If compliance with the reserve energy absorption requirement in § 23.723(b) is shown by free drop tests, the drop height may not be less... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Reserve energy absorption drop test....

  8. 14 CFR 23.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Construction Landing Gear § 23.727 Reserve energy absorption drop test. (a) If compliance with the reserve energy absorption requirement in § 23.723(b) is shown by free drop tests, the drop height may not be less... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Reserve energy absorption drop test....

  9. 14 CFR 23.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Construction Landing Gear § 23.727 Reserve energy absorption drop test. (a) If compliance with the reserve energy absorption requirement in § 23.723(b) is shown by free drop tests, the drop height may not be less... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Reserve energy absorption drop test....

  10. 14 CFR 23.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Construction Landing Gear § 23.727 Reserve energy absorption drop test. (a) If compliance with the reserve energy absorption requirement in § 23.723(b) is shown by free drop tests, the drop height may not be less... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Reserve energy absorption drop test....

  11. 49 CFR 178.603 - Drop test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... jerricans, plastic boxes other than expanded polystyrene boxes, composite packagings (plastic material), and... drums, Plastic drums and Jerricans, Composite packagings which are in the shape of a drum Six—(three for... aluminum boxes, Composite packagings which are in the shape of a box Five—(one for each drop) First...

  12. 49 CFR 178.810 - Drop test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... the drop test. (1) Metal, rigid plastic, and composite IBCs intended to contain solids must be filled... plugged or rendered inoperative. (2) Fiberboard and wooden IBCs must be filled with a solid material to.... (4) Rigid plastic IBCs and composite IBCs with plastic inner receptacles must be conditioned...

  13. 49 CFR 178.810 - Drop test.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... the drop test. (1) Metal, rigid plastic, and composite IBCs intended to contain solids must be filled... plugged or rendered inoperative. (2) Fiberboard and wooden IBCs must be filled with a solid material to.... (4) Rigid plastic IBCs and composite IBCs with plastic inner receptacles must be conditioned...

  14. 49 CFR 178.810 - Drop test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... the drop test. (1) Metal, rigid plastic, and composite IBCs intended to contain solids must be filled... plugged or rendered inoperative. (2) Fiberboard and wooden IBCs must be filled with a solid material to.... (4) Rigid plastic IBCs and composite IBCs with plastic inner receptacles must be conditioned...

  15. Utah Drop-Out Drug Use Questionnaire.

    ERIC Educational Resources Information Center

    Governor's Citizen Advisory Committee on Drugs, Salt Lake City, UT.

    This questionnaire assesses drug use practices in high school drop-outs. The 79 items (multiple choice or apply/not apply) are concerned with demographic data and use, use history, reasons for use/nonuse, attitudes toward drugs, availability of drugs, and drug information with respect to narcotics, amphetamines, LSD, Marijuana, and barbiturates.

  16. Sessile drop deformations under an impinging jet

    NASA Astrophysics Data System (ADS)

    Feng, James Q.

    2015-08-01

    The problem of steady axisymmetric deformations of a liquid sessile drop on a flat solid surface under an impinging gas jet is of interest for understanding the fundamental behavior of free surface flows as well as for establishing the theoretical basis in process design for the Aerosol direct-write technology. It is studied here numerically using a Galerkin finite-element method, by computing solutions of Navier-Stokes equations. For effective material deposition in Aerosol printing, the desired value of Reynolds number for the laminar gas jet is found to be greater than ~500. The sessile drop can be severely deformed by an impinging gas jet when the capillary number is approaching a critical value beyond which no steady axisymmetric free surface deformation can exist. Solution branches in a parameter space show turning points at the critical values of capillary number, which typically indicate the onset of free surface shape instability. By tracking solution branches around turning points with an arc-length continuation algorithm, critical values of capillary number can be accurately determined. Near turning points, all the free surface profiles in various parameter settings take a common shape with a dimple at the center and bulge near the contact line. An empirical formula for the critical capillary number for sessile drops with contact angle is derived for typical ranges of jet Reynolds number and relative drop sizes especially pertinent to Aerosol printing.

  17. Behavior Of Evaporating Liquid Drops In Clusters

    NASA Technical Reports Server (NTRS)

    Bellan, Josette

    1990-01-01

    Report presents critical analysis of methods, developed for calculating behavior of evaporating liquid drops in dense and dilute clusters. Essential to understanding variety of physical and chemical phenomena occurring in combustion of sprayed fuels and in sprays used in agriculture, food industry, and painting. Presents insights on important aspects of two-phase flow.

  18. 49 CFR 178.965 - Drop test.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    .... Water/anti-freeze solutions with a minimum specific gravity of 0.95 for testing at −18 °C (0 °F) or... having essentially the same physical characteristics. (3) The specific gravity and viscosity of a...: (i) Where the substances to be carried have a specific gravity not exceeding 1.2, the drop...

  19. Allergic Contact Dermatitis to Eye Drops

    PubMed Central

    Bhat, Yasmeen Jabeen; Zeerak, Sumaya; Hassan, Iffat

    2015-01-01

    Allergic contact dermatitis (ACD) occurs due to a milieu of allergens and involves different anatomical sites, including eyelids, and periorbital areas. Topically applied ophthalmic drugs are a potential cause of ACD of the periorbital region. Here we describe the report of a patient who developed ACD to eye drop preparations. PMID:26677304

  20. Student Drops and Failure in Principles Courses

    ERIC Educational Resources Information Center

    Bosshardt, William

    2004-01-01

    Many studies have identified factors that contribute to success in economics principles courses, but few have examined the causes and effects of student drops and failure. The author follows 239 students through their economic principles course and tracks the students in the year after the course. The author constructs a model predicting student…

  1. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. NASA and contractor personnel who conducted the DIME activity with the students. Shown (L-R) are: Eric Baumann (NASA, 2.2-second Drop Tower Facility manager), Daniel Dietrich (NASA) mentor for Sycamore High School team), Carol Hodanbosi (National Center for Microgravity Research; DIME staff), Richard DeLombard (NASA; DIME staff), Jose Carrion (GRC Akima, drop tower technician), Dennis Stocker (NASA; DIME staff), Peter Sunderland (NCMR, mentor for COSI Academy student team), Sandi Thompson (NSMR sabbatical teacher; DIME staff), Dan Woodard (MASA Microgravity Outreach Program Manager), Adam Malcolm (NASA co-op student; DIME staff), Carla Rosenberg (NCMR; DIME staff), and Twila Schneider (Infinity Technology; NASA Microgravity Research program contractor). This image is from a digital still camera; higher resolution is not available.

  2. 49 CFR 178.965 - Drop test.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... Water/anti-freeze solutions with a minimum specific gravity of 0.95 for testing at −18 °C (0 °F) or... having essentially the same physical characteristics. (3) The specific gravity and viscosity of a...: (i) Where the substances to be carried have a specific gravity not exceeding 1.2, the drop...

  3. 49 CFR 178.965 - Drop test.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... Water/anti-freeze solutions with a minimum specific gravity of 0.95 for testing at −18 °C (0 °F) or... having essentially the same physical characteristics. (3) The specific gravity and viscosity of a...: (i) Where the substances to be carried have a specific gravity not exceeding 1.2, the drop...

  4. Predicting Students Drop Out: A Case Study

    ERIC Educational Resources Information Center

    Dekker, Gerben W.; Pechenizkiy, Mykola; Vleeshouwers, Jan M.

    2009-01-01

    The monitoring and support of university freshmen is considered very important at many educational institutions. In this paper we describe the results of the educational data mining case study aimed at predicting the Electrical Engineering (EE) students drop out after the first semester of their studies or even before they enter the study program…

  5. Acoustic forcing of a liquid drop

    NASA Technical Reports Server (NTRS)

    Lyell, M. J.

    1992-01-01

    The development of systems such as acoustic levitation chambers will allow for the positioning and manipulation of material samples (drops) in a microgravity environment. This provides the capability for fundamental studies in droplet dynamics as well as containerless processing work. Such systems use acoustic radiation pressure forces to position or to further manipulate (e.g., oscillate) the sample. The primary objective was to determine the effect of a viscous acoustic field/tangential radiation pressure forcing on drop oscillations. To this end, the viscous acoustic field is determined. Modified (forced) hydrodynamic field equations which result from a consistent perturbation expansion scheme are solved. This is done in the separate cases of an unmodulated and a modulated acoustic field. The effect of the tangential radiation stress on the hydrodynamic field (drop oscillations) is found to manifest as a correction to the velocity field in a sublayer region near the drop/host interface. Moreover, the forcing due to the radiation pressure vector at the interface is modified by inclusion of tangential stresses.

  6. An evaporation model of multicomponent solution drops

    NASA Astrophysics Data System (ADS)

    Sartori, Silvana; Liñán, Amable; Lasheras, Juan C.

    2010-11-01

    Solutions of polymers are widely used in the pharmaceutical industry as tablets coatings. These allow controlling the rate at which the drug is delivered, taste or appearance. The coating is performed by spraying and drying the tablets at moderate temperatures. The wetting of the coating solution on the pill's surface depends on the droplet Webber and Re numbers, angle of impact and on the rheological properties of the droplet. We present a model for the evaporation of multicomponent solutions droplets in a hot air environment with temperatures substantially lower than the boiling temperature of the solvent. As the liquid vaporizes from the surface the fluid in the drop increases in concentration, until reaching its saturation point. After saturation, precipitation occurs uniformly within the drop. As the surface regresses, a compacting front formed by the precipitate at its maximum packing density advances into the drop, while the solute continues precipitating uniformly. This porous shell grows fast due to the double effect of surface regression and precipitation. The evaporation rate is determined by the rates at which heat is transported to the droplet surface and at which liquid vapor diffuses away from it. When the drop is fully compacted, the evaporation is drastically reduced.

  7. Suppressing Viscous Drop Splashing with Surface Roughness

    NASA Astrophysics Data System (ADS)

    Strandburg-Peshkin, Ariana; Driscoll, Michelle; Nagel, Sidney

    2009-11-01

    The splashing of a liquid drop on a smooth, dry surface depends on a host of factors: the speed, surface tension, viscosity and size of the drop, but also, surprisingly, the pressure and molecular weight of the surrounding gas.footnotetext L. Xu, W.W. Zhang, S.R. Nagel, PRL 94, 184505 (2005).^,footnotetext L. Xu, PRE 75, 056316 (2007). In the case of a viscous drop splashing on a smooth surface, a thin sheet of fluid is first ejected from the rim of the expanding drop and then breaks up into droplets to form a splash.footnotetextM. Driscoll et al., BAPS DFD AG.00005 (2008). When the surface is rough, different behavior, known as prompt splashing, may also be observed.^2,footnotetext L. Xu, L. Barcos, and S.R. Nagel, PRE 76 066311 (2007). Here we explore the splashing of a viscous liquid as the surface roughness, Ra, is varied. We find that a small degree of roughness, Ra< 1 μm, can completely suppress the thin-sheet ejection occurring on smooth surfaces. The degree of roughness necessary for this suppression decreases with increasing viscosity. In some cases, the roughness is great enough to suppress the thin sheet, but insufficient to produce a prompt splash, thus suppressing the splash entirely.

  8. Utah Drop-Out Drug Use Questionnaire.

    ERIC Educational Resources Information Center

    Governor's Citizen Advisory Committee on Drugs, Salt Lake City, UT.

    This questionnaire assesses drug use practices in high school drop-outs. The 79 items (multiple choice or apply/not apply) are concerned with demographic data and use, use history, reasons for use/nonuse, attitudes toward drugs, availability of drugs, and drug information with respect to narcotics, amphetamines, LSD, Marijuana, and barbiturates.…

  9. Containerless undercooling and solidification in drop tubes

    NASA Technical Reports Server (NTRS)

    Lacy, L. L.; Robinson, M. B.; Rathz, T. J.

    1981-01-01

    A containerless low-gravity environment, produced within a 32 m drop tube apparatus, has been used to undercool and solidify metals, alloys or glasses by eliminating crucible induced nucleation processes. Niobium droplets with diameters in the range of 2 to 5 mm have been undercooled by 525 K which corresponds to the maximum undercooling reported by Turnbull and others on fine dispersions of low melting point metals. Solidification at large undercooling resulted in single crystalline spheres with the formation of interdendritic shrinkage channels on the sample surface rather than interior shrinkage cavities. The grain refinement as observed for Ni samples undercooled and solidified in fused silica crucibles does not occur in free-falling drops of Nb. A calculated solidification speed of undercooled Nb is compared to Ni. A solidification speed of 320 m/s is found for the Nb drops. This solidification speed is greater than or comparable to the solidification speeds calculated in splat cooled samples. Thus, a drop tube apparatus can be useful in the preparation and study of high temperature metastable compounds or alloys in bulk form.

  10. Viscosity Measurement Using Drop Coalescence in Microgravity

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.; Ethridge, Edwin C.; Maxwell, Daniel; Curreri, Peter A. (Technical Monitor)

    2002-01-01

    We present in here validation studies of a new method for application in microgravity environment which measures the viscosity of highly viscous undercooled liquids using drop coalescence. The method has the advantage of avoiding heterogeneous nucleation at container walls caused by crystallization of undercooled liquids during processing. Homogeneous nucleation can also be avoided due to the rapidity of the measurement using this method. The technique relies on measurements from experiments conducted in near zero gravity environment as well as highly accurate analytical formulation for the coalescence process. The viscosity of the liquid is determined by allowing the computed free surface shape relaxation time to be adjusted in response to the measured free surface velocity for two coalescing drops. Results are presented from two sets of validation experiments for the method which were conducted on board aircraft flying parabolic trajectories. In these tests the viscosity of a highly viscous liquid, namely glycerin, was determined at different temperatures using the drop coalescence method described in here. The experiments measured the free surface velocity of two glycerin drops coalescing under the action of surface tension alone in low gravity environment using high speed photography. The liquid viscosity was determined by adjusting the computed free surface velocity values to the measured experimental data. The results of these experiments were found to agree reasonably well with the known viscosity for the test liquid used.

  11. Alternative scenarios utilizing nonterrestrial resources

    NASA Technical Reports Server (NTRS)

    Eldred, Charles H.; Roberts, Barney B.

    1992-01-01

    A collection of alternative scenarios that are enabled or substantially enhanced by the utilization of nonterrestrial resources is provided. We take a generalized approach to scenario building so that our report will have value in the context of whatever goals are eventually chosen. Some of the topics covered include the following: lunar materials processing; asteroid mining; lunar resources; construction of a large solar power station; solar dynamic power for the space station; reduced gravity; mission characteristics and options; and tourism.

  12. Security message exchange interoperability scenarios

    SciTech Connect

    Tarman, Thomas

    1998-07-01

    This contribution describes three interoperability scenarios for the ATM Security Message Exchange (SME) protocol. These scenarios include network-wide signaling support for the Security Services Information Element, partial signaling support wherethe SSIE is only supported in private or workgroup ATM networks, and the case where the SSIE is nonsupported by any network elements (exceptthosethat implement security services). Explanatory text is proposed for inclusion infection 2.3 of the ATM Security Specification, Version 1.0.

  13. Do not drop: mechanical shock in vials causes cavitation, protein aggregation, and particle formation.

    PubMed

    Randolph, Theodore W; Schiltz, Elise; Sederstrom, Donn; Steinmann, Daniel; Mozziconacci, Olivier; Schöneich, Christian; Freund, Erwin; Ricci, Margaret S; Carpenter, John F; Lengsfeld, Corrine S

    2015-02-01

    Industry experience suggests that g-forces sustained when vials containing protein formulations are accidentally dropped can cause aggregation and particle formation. To study this phenomenon, a shock tower was used to apply controlled g-forces to glass vials containing formulations of two monoclonal antibodies and recombinant human growth hormone (rhGH). High-speed video analysis showed cavitation bubbles forming within 30 μs and subsequently collapsing in the formulations. As a result of echoing shock waves, bubbles collapsed and reappeared periodically over a millisecond time course. Fluid mechanics simulations showed low-pressure regions within the fluid where cavitation would be favored. A hydroxyphenylfluorescein assay determined that cavitation produced hydroxyl radicals. When mechanical shock was applied to vials containing protein formulations, gelatinous particles appeared on the vial walls. Size-exclusion chromatographic analysis of the formulations after shock did not detect changes in monomer or soluble aggregate concentrations. However, subvisible particle counts determined by microflow image analysis increased. The mass of protein attached to the vial walls increased with increasing drop height. Both protein in bulk solution and protein that became attached to the vial walls after shock were analyzed by mass spectrometry. rhGH recovered from the vial walls in some samples revealed oxidation of Met and/or Trp residues. PMID:25418950

  14. DO NOT DROP: MECHANICAL SHOCK IN VIALS CAUSES CAVITATION, PROTEIN AGGREGATION AND PARTICLE FORMATION

    PubMed Central

    Randolph, Theodore W.; Schiltz, Elise; Sederstrom, Donn; Steinmann, Daniel; Mozziconacci, Olivier; Schöneich, Christian; Freund, Erwin; Ricci, Margaret S.; Carpenter, John F.; Lengsfeld, Corrine S.

    2014-01-01

    Industry experience suggests that g-forces sustained when vials containing protein formulations are accidentally dropped can cause aggregation and particle formation. To study this phenomenon, a shock tower was used to apply controlled g-forces to glass vials containing formulations of two monoclonal antibodies and recombinant human growth hormone (rhGH). High-speed video analysis showed cavitation bubbles forming within 30 μs and subsequently collapsing in the formulations. As a result of echoing shock waves, bubbles collapsed and reappeared periodically over a millisecond timecourse. Fluid mechanics simulations showed low-pressure regions within the fluid where cavitation would be favored. A hydroxyphenylfluorescein assay determined that cavitation produced hydroxyl radicals. When mechanical shock was applied to vials containing protein formulations, gelatinous particles appeared on the vial walls. Size exclusion chromatographic analysis of the formulations after shock did not detect changes in monomer or soluble aggregate concentrations. However, subvisible particle counts determined by microflow image analysis increased. The mass of protein attached to the vial walls increased with increasing drop height. Both protein in bulk solution and protein that became attached to the vial walls after shock were analyzed by mass spectrometry. rhGH recovered from the vial walls in some samples revealed oxidation of Met and/or Trp residues. PMID:25418950

  15. Instabilities of volatile films and drops

    NASA Astrophysics Data System (ADS)

    Murisic, Nebojsa

    2008-12-01

    We report on instabilities during spreading of volatile liquids, with emphasis on the novel instability observed when isopropyl alcohol (IPA) is deposited on a monocrystalline silicon (Si) wafer. This instability is characterized by emission of drops ahead of the expanding front, with each drop followed by smaller, satellite droplets, forming the structures which we nickname "octopi" due to their appearance. A less volatile liquid, or a substrate of larger heat conductivity, suppress this instability. In addition, we examine the spreading of drops of water (DIW)-IPA mixtures on both Si wafers and plain glass slides, and describe the variety of contact line instabilities which appear. We find that the decrease of IPA concentration in mixtures leads to transition from "octopi" to mushroom-like instabilities. Through manipulation of our experimental set up, we also find that the mechanism responsible for these instabilities appears to be mostly insensitive to both the external application of convection to the gas phase, and the doping of the gas phase with vapor in order to create the saturated environment. In order to better understand the "octopi" instability, we develop a theoretical model for evaporation of a pure liquid drop on a thermally conductive solid substrate. This model includes all relevant physical effects, including evaporation, thermal conductivity in both liquid and solid, (thermocapillary) Marangoni effect, vapor recoil, disjoining pressure, and gravity. The crucial ingredient in this problem is the evaporation model, since it influences both the motion of the drop contact line, and the temperature profiles along the liquid-solid and liquid-gas interfaces. We consider two evaporation models: the equilibrium "lens" model and the non-equilibrium one-sided (NEOS) model. Along with the assumption of equilibrium at the liquid-gas interface, the "lens" model also assumes that evaporation proceeds in a (vapor) diffusion-limited regime, therefore bringing the focus to the gas phase, where the problem of vapor mass diffusion is to be solved, which invokes analogy with the problem of lens-shaped conductor from electrostatics. On the other hand, NEOS model assumes non-equilibrium at the liquid-gas interface and a reaction-limited regime of evaporation; the liquid and gas phases are decoupled using the one-sided assumption, and hence, the problem is to be solved in the liquid phase only. We use lubrication approximation and derive a single governing equation for the evolution of drop thickness, which includes both models. An experimental procedure is described next, which we use in order to estimate the volatility parameter corresponding to each model. We also describe the numerical code, which we use to solve the governing equation for drop thickness, and show how this equation can be used to predict which evaporation model is more appropriate for a particular physical problem. Next, we perform linear stability analysis (LSA) of perturbed thin film configuration. We find excellent agreement between our numerical results and LSA predictions. Furthermore, these results indicate that the IPA/Si configuration is the most unstable one, in direct agreement with experimental results. We perform numerical simulations in the simplified 2d geometry (cross section of the drop) for both planar and radial symmetry and show that our theoretical model reproduces the main features of the experiment, namely, the formation of "octopus"-like features ahead of the contact line of an evaporating drop. Finally, we perform quasi-3d numerical simulations of evaporating drops, where stability to azimuthal perturbations of the contact line is examined. We recover the "octopi" instability for IPA/Si configuration, similarly as seen in the experiments.

  16. Optimum Drop Height for Maximizing Power Output in Drop Jump: The Effect of Maximal Muscle Strength.

    PubMed

    Matic, Milan S; Pazin, Nemanja R; Mrdakovic, Vladimir D; Jankovic, Nenad N; Ilic, Dusko B; Stefanovic, Djordje L J

    2015-12-01

    The main purpose of this study was to explore the cause-and-effect relation of maximal muscle strength (MSmax) on the optimum drop height (DHopt) that maximizes power output in drop jump. In total, 30 physically active male students participated in this study, whereas the 16 subjects were selected according to their resistance strength training background (i.e., level of MSmax) and allocated into 2 equal subgroups: strong (n = 8) and weak (n = 8). The main testing session consisted of drop jumps performed from 8 different drop heights (i.e., from 0.12 to 0.82 m). The individual DHopt was determined based on the maximal value power output across applied ranges of drop heights. The tested relationships between DHopt and MSmax were moderate (r = 0.39-0.50, p ? 0.05). In addition, the stronger individuals, on average, showed maximal values of power output on the higher drop height compared with the weaker individuals (0.62 vs. 0.32 m). Finally, significant differences in the individual DHopt between groups were detected (p < 0.01). The present findings suggest that drop height should be adjusted based on a subject's neuromuscular capacity to produce MSmax. Hence, from the perspective of strength and conditioning practitioners, MSmax should be considered as an important factor that could affect the DHopt, and therefore should be used for its adjustment in terms of optimizing athlete's testing, training, or rehabilitation intervention. PMID:26020711

  17. PREVENTION REFERENCE MANUAL: CHEMICAL SPECIFIC. VOLUME 8. CONTROL OF ACCIDENTAL RELEASES OF HYDROGEN FLUORIDE

    EPA Science Inventory

    The report is a chemical specific manual for hydrogen fluoride (HF). It summarizes information to aid regulators and industry personnel in identifying and controlling release hazards associated with HF. Reducing the risk associated with accidental release of HF involves identifyi...

  18. Drop impact on inclined superhydrophobic surfaces.

    PubMed

    LeClear, Sani; LeClear, Johnathon; Abhijeet; Park, Kyoo-Chul; Choi, Wonjae

    2016-01-01

    This paper discusses the dynamic behavior of water drops impacting on inclined superhydrophobic surfaces. For a normal impact on a smooth hydrophobic surface, the spreading (or expansion) and retraction dynamics of an impacting drop varies from complete rebound to splashing depending on its Weber number, (We(d)), calculated using the impact speed and diameter d of the drop. For a slanted impact, on the other hand, the impact dynamics depends on two distinct Weber numbers, based on the velocity components normal, (We(nd)), and tangential, (We(td)), to the surface. Impact on superhydrophobic surfaces is even more complicated as the surfaces are covered with micro- to nano-scale texture. Therefore, we develop an expression for an additional set of two Weber numbers, (We(na), We(ta)), which are counterparts to the first set but use the gap distance a between asperities on the textured surface as the characteristic length. We correlate the derived Weber numbers with the impact dynamics on tilted surfaces covered with three different types of texture: (i) posts, (ii) ridges aligned with and (iii) ridges perpendicular to the impact direction. Results suggest that the first two Weber numbers, (We(nd), We(td)), affect the impact dynamics of a drop such as the degree of drop deformation as long as the superhydrophobicity remains intact. On the other hand, the Weber number We(na) determines the transition from the superhydrophobic Cassie-Baxter regime to the fully-wetted Wenzel regime. Accuracy of our model becomes lower at a high tilting angle (75°), due to the change in the transition mechanism. PMID:26397917

  19. Simulations of Evaporating Multicomponent Fuel Drops

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Le Clercq, Patrick

    2005-01-01

    A paper presents additional information on the subject matter of Model of Mixing Layer With Multicomponent Evaporating Drops (NPO-30505), NASA Tech Briefs, Vol. 28, No. 3 (March 2004), page 55. To recapitulate: A mathematical model of a three-dimensional mixing layer laden with evaporating fuel drops composed of many chemical species has been derived. The model is used to perform direct numerical simulations in continuing studies directed toward understanding the behaviors of sprays of liquid petroleum fuels in furnaces, industrial combustors, and engines. The model includes governing equations formulated in an Eulerian and a Lagrangian reference frame for the gas and drops, respectively, and incorporates a concept of continuous thermodynamics, according to which the chemical composition of a fuel is described by use of a distribution function. In this investigation, the distribution function depends solely on the species molar weight. The present paper reiterates the description of the model and discusses further in-depth analysis of the previous results as well as results of additional numerical simulations assessing the effect of the mass loading. The paper reiterates the conclusions reported in the cited previous article, and states some new conclusions. Some new conclusions are: 1. The slower evaporation and the evaporation/ condensation process for multicomponent-fuel drops resulted in a reduced drop-size polydispersity compared to their single-component counterpart. 2. The inhomogeneity in the spatial distribution of the species in the layer increases with the initial mass loading. 3. As evaporation becomes faster, the assumed invariant form of the molecular- weight distribution during evaporation becomes inaccurate.

  20. Accidental infusion leakage at subgalea in infants: report of 6 cases

    PubMed Central

    An, Bo; Ning, Haojie

    2015-01-01

    Infiltration remains the commonest iatrogenic injury within infants care. We report a series of 6 infants affected by accidental infusion leakage occurring in subgalea. They were applied wet-hot compresses by sterile gauze, and topically administrated mucopolysaccharide polysulfate (MPS) cream following hot compress. There was no skin impairment in all cases. Early recognition and appropriate care for topical skin are essential to minimize the extent of accidental infusion leakage. PMID:26550108

  1. Acute health effects of accidental chlorine gas exposure

    PubMed Central

    2014-01-01

    Objectives This study was conducted to report the course of an accidental release of chlorine gas that occurred in a factory in Gumi-si, South Korea, on March 5, 2013. We describe the analysis results of 2 patients hospitalized because of chlorine-induced acute health problems, as well as the clinical features of 209 non-hospitalized patients. Methods We analyzed the medical records of the 2 hospitalized patients admitted to the hospital, as well as the medical records and self-report questionnaires of 209 non-hospitalized patients completed during outpatient treatment. Results Immediately after the exposure, the 2 hospitalized patients developed acute asthma-like symptoms such as cough and dyspnea, and showed restrictive and combined pattern ventilatory defects on the pulmonary function test. The case 1 showed asthma-like symptoms over six months and diurnal variability in peak expiratory flow rate was 56.7%. In case 2, his FEV1 after treatment (93%) increased by 25% compared to initial FEV1 (68%). Both cases were diagnosed as chlorine-induced reactive airways dysfunction syndrome (RADS) on the basis of these clinical features. The most frequent chief complaints of the 209 non-hospitalized patients were headache (22.7%), followed by eye irritation (18.2%), nausea (11.2%), and sore throat (10.8%), with asymptomatic patients accounting for 36.5%. The multiple-response analysis of individual symptom revealed headache (42.4%) to be the most frequent symptom, followed by eye irritation (30.5%), sore throat (30.0%), cough (29.6%), nausea (27.6%), and dizziness (27.3%). Conclusions The 2 patients hospitalized after exposure to chlorine gas at the leakage site showed a clinical course corresponding to RADS. All of the 209 non-hospitalized patients only complained of symptoms of the upper airways and mucous membrane irritation. PMID:25852940

  2. Laboratory-Acquired Parasitic Infections from Accidental Exposures

    PubMed Central

    Herwaldt, Barbara L.

    2001-01-01

    Parasitic diseases are receiving increasing attention in developed countries in part because of their importance in travelers, immigrants, and immunocompromised persons. The main purpose of this review is to educate laboratorians, the primary readership, and health care workers, the secondary readership, about the potential hazards of handling specimens that contain viable parasites and about the diseases that can result. This is accomplished partly through discussion of the occupationally acquired cases of parasitic infections that have been reported, focusing for each case on the type of accident that resulted in infection, the length of the incubation period, the clinical manifestations that developed, and the means by which infection was detected. The article focuses on the cases of infection with the protozoa that cause leishmaniasis, malaria, toxoplasmosis, Chagas' disease (American trypanosomiasis), and African trypanosomiasis. Data about 164 such cases are discussed, as are data about cases caused by intestinal protozoa and by helminths. Of the 105 case-patients infected with blood and tissue protozoa who either recalled an accident or for whom the likely route of transmission could be presumed, 47 (44.8%) had percutaneous exposure via a contaminated needle or other sharp object. Some accidents were directly linked to poor laboratory practices (e.g., recapping a needle or working barehanded). To decrease the likelihood of accidental exposures, persons who could be exposed to pathogenic parasites must be thoroughly instructed in safety precautions before they begin to work and through ongoing training programs. Protocols should be provided for handling specimens that could contain viable organisms, using protective clothing and equipment, dealing with spills of infectious organisms, and responding to accidents. Special care should be exercised when using needles and other sharp objects. PMID:11585780

  3. Persistent Seroconversion after Accidental Eye Exposure to Calcifying Nanoparticles

    NASA Technical Reports Server (NTRS)

    Ciftcioglu, Neva; Aho, Katja M.; McKay, David S.; Kajander, E. Olavi

    2007-01-01

    Biosafety of nanomaterials has attracted much attention recently. We report here a case where accidental human eye exposure to biogenic nanosized calcium phosphate in the form of calcifying nanoparticles (CNP) raised a strong IgG immune response against proteins carried by CNP. The antibody titer has persisted over ten years at the high level. The IgG was detected by ELISA using CNPs propagated in media containing bovine and human serum as antigen. The exposure incident occurred to a woman scientist (WS) at a research laboratory in Finland at 1993. CNP, also termed "nanobacteria", is a unique self-replicating agent that has not been fully characterized and no data on biohazards were available at that time. Before the accident, her serum samples were negative for both CNP antigen and anti-CNP antibody using specific ELISA tests (Nanobac Oy, Kuopio, Finland). The accident occurred while WS was harvesting CNP cultures. Due to a high pressure in pipetting, CNP pellet splashed into her right eye. Both eyes were immediately washed with water and saline. The following days there was irritation and redness in the right eye. These symptoms disappeared within two weeks without any treatment. Three months after the accident, blood and urine samples of WS were tested for CNP cultures (2), CNP-specific ELISA tests, and blood cell counts. Blood cell counts were normal, CNP antigen and culture tests were negative. A high IgG anti-CNP antibody titer was detected (see Figure). The antibodies of this person have been used thereafter as positive control and standard in ELISA manufacturing (Nano-Sero IgG ELISA, Nanobac Oy, Kuopio, Finland).

  4. Targeting of observations for accidental atmospheric release monitoring

    NASA Astrophysics Data System (ADS)

    Abida, Rachid; Bocquet, Marc

    2009-12-01

    In the event of an accidental atmospheric release of radionuclides from a nuclear power plant, accurate real-time forecasting of the activity concentrations of radionuclides is acutely required by the decision makers for the preparation of adequate countermeasures. Yet, the accuracy of the forecasted plume is highly dependent on the source term estimation. Inverse modelling and data assimilation techniques should help in that respect. However the plume can locally be thin and could avoid a significant part of the radiological monitoring network surrounding the plant. Deploying mobile measuring stations following the accident could help to improve the source term estimation. In this paper, a method is proposed for the sequential reconstruction of the plume, by coupling a sequential data assimilation algorithm based on inverse modelling with an observation targeting strategy. The targeting design strategy consists in seeking the optimal locations of the mobile monitors at time t + 1 based on all available observations up to time t. The performance of the sequential assimilation with and without targeting of observations has been assessed in a realistic framework. It focuses on the Bugey nuclear power plant (France) and its surroundings within 50 km from the plant. The existing surveillance network is used and realistic observational errors are assumed. The targeting scheme leads to a better estimation of the source term as well as the activity concentrations in the domain. The mobile stations tend to be deployed along plume contours, where activity concentration gradients are important. It is shown that the information carried by the targeted observations is very significant, as compared to the information content of fixed observations. A simple test on the impact of model error from meteorology shows that the targeting strategy is still very useful in a more uncertain context.

  5. Drop spreading at the impact in the Leidenfrost boiling

    NASA Astrophysics Data System (ADS)

    Castanet, G.; Caballina, O.; Lemoine, F.

    2015-06-01

    Although the Leidenfrost effect has been extensively studied in the past, one challenge for the modeling of this phenomenon remains, namely, how to determine the effect induced by the presence of a vapor film on the frictions exerted on the drop. To address this issue, experiments are carried out on liquids with very different viscosities including water, ethanol, and several mixtures of water and glycerol. The deformation of droplets of a few hundred micrometers, impinging a perfectly smooth solid surface heated above the Leidenfrost temperature, is observed by shadowgraphy using a high-speed camera. Experimental results are compared to a theoretical model which is based on an inviscid asymptotic solution for the flow inside the lamella. This model also considers a lamella thickness which does not depend on the viscosity, the surface tension, and thus on the Reynolds and Weber numbers. This description of the lamella is valid if Weber and Reynolds numbers are high enough. Mass and momentum balances applied to the rim bounding the spreading lamella yield an equation for the rim motion which is then solved numerically. This equation accounts for the momentum transferred to the rim by the liquid coming from the lamella, the capillary forces, and the viscous stress at the separation between the lamella and the rim. The comparison between the model and the experiments suggests that the liquid at the bottom edge of the lamella is dragged by the vapor film given that the vapor velocity in the vapor film is significantly larger than that of the liquid. This process significantly increases the drop spreading for the low viscosity liquids. An analysis of the viscous boundary layer which develops at the bottom edge of the lamella is found to confirm this scenario.

  6. Baseline scenario(s) for muon collider proton driver

    SciTech Connect

    Jansson, Andreas; /Fermilab

    2008-07-01

    This paper gives an overview of the various muon collider scenarios and the requirements they put on the Proton Driver. The required proton power is about 4-6MW in all the scenarios, but the bunch repetition rate varies between 12 and 65Hz. Since none of the muon collider scenarios have been simulated end-to-end, it would be advisable to plan for an upgrade path to around 10MW. Although the proton driver energy is flexible, cost arguments seems to favor a relatively low energy. In particular, at Fermilab 8GeV seems most attractive, partly due to the possibility of reusing the three existing fixed energy storage rings for bunch manipulations.

  7. Medical Scenarios Relevant to Spaceflight

    NASA Technical Reports Server (NTRS)

    Bacal, Kira; Hurs, Victor; Doerr, Harold

    2004-01-01

    The Medical Operational Support Team (MOST) was tasked by the JSC Space Medicine and Life Sciences Directorate (SLSD) to incorporate medical simulation into 1) medical training for astronaut-crew medical officers (CMO) and medical flight control teams and 2) evaluations of procedures and resources required for medical care aboard the International Space Station (ISS). Development of evidence-based medical scenarios that mimic the physiology observed during spaceflight will be needed for the MOST to complete these two tasks. The MOST used a human patient simulator, the ISS-like resources in the Medical Simulation Laboratory (MSL), and evidence from space operations, military operations and medical literature to develop space relevant medical scenarios. These scenarios include conditions concerning airway management, Advanced Cardiac Life Support (ACLS) and mitigating anaphylactic symptoms. The MOST has used these space relevant medical scenarios to develop a preliminary space medical training regimen for NASA flight surgeons, Biomedical Flight Controllers (Biomedical Engineers; BME) and CMO-analogs. This regimen is conducted by the MOST in the MSL. The MOST has the capability to develop evidence-based space-relevant medical scenarios that can help SLSD I) demonstrate the proficiency of medical flight control teams to mitigate space-relevant medical events and 2) validate nextgeneration medical equipment and procedures for space medicine applications.

  8. Head-on collision of drops: A numerical investigation

    NASA Technical Reports Server (NTRS)

    Nobari, M. R.; Jan, Y.-J.; Tryggvason, G.

    1993-01-01

    The head-on collision of equal sized drops is studied by full numerical simulations. The Navier-Stokes equations are solved for fluid motion both inside and outside the drops using a front tracking/finite difference technique. The drops are accelerated toward each other by a body force that is turned off before the drops collide. When the drops collide, the fluid between them is pushed outward leaving a thin later bounded by the drop surface. This layer gets progressively thinner as the drops continue to deform and in several of the calculations this double layer is artificially removed once it is thin enough, thus modeling rupture. If no rupture takes place, the drops always rebound, but if the film is ruptured the drops may coalesce permanently or coalesce temporarily and then split again.

  9. COD measurement based on the integrated liquid drop sensor

    NASA Astrophysics Data System (ADS)

    Qiu, Zurong; Zhang, Guoxiong; Song, Qing; Xu, Jian

    2005-02-01

    A study on Chemical Oxygen Demand (COD) measuring method is reported, in which the COD value is measured by an integrated liquid drop monitor sensor without any reagent and chemical treatment. The integrated drop sensor consists of a liquid head, an integrated fiber sensor and a capacitor sensor. The capacitor sensor is composed of a drop head and a ring electrode. As the part of the drop head, the outline of the drop will be changed during the drop forming, which result in the variation of the capacitance. The fiber sensor is composed of two fibers that are positioned into the liquid drop. The light signal goes into the liquid drop from one fiber and out from the other one. A unique fingerprint of the liquid drop can be got by the data processing. The matching between the COD value of a liquid and the codes of the fingerprints in the database are presented and discussed.

  10. Surface and Bulk Oscillations of Sessile Drops: Clearing Up Confusion and Understanding Wind Sheared Drops

    NASA Astrophysics Data System (ADS)

    Milne, Andrew J. B.; Defez Garcia, Beatriz; Cabrerizo Vilchez, Miguel; Amirfazli, Alidad

    2011-11-01

    Sessile drop oscillations are studied in the presence of a shearing airflow, and varying body force. The various possibilities for analysis, (center of mass or drop surface oscillations) are elucidated through presenting a unifying analysis framework based on wavenumber, frequency, and fluid properties. This work examines a range of fluid properties in a single study for the first time. A dispersion relation is found relating the frequency of centroid oscillation and capillary-gravity wave number, depending on the ratio (surface tension/liquid density)1/2, drop size- 3 / 2 and contact angle. The effects of contact angle are more complex than previously suggested simplifications, or analytic solutions for axisymetric drops and must at present be treated empirically. The growth of sessile drop oscillations is linear at low air velocities and exponential at higher air velocities. This is explained by drawing analogies to drops experiencing a varying body force, and to wind driven capillary-gravity waves on lakes, respectively. Liquid viscosity retards the growth of the waves, and has other important effects.

  11. Cracks formation during blood drop evaporation

    NASA Astrophysics Data System (ADS)

    Sobac, Benjamin; Brutin, David; Université de Provence Team

    2011-03-01

    We firstly presented the pattern formation occurring when drops of whole blood desiccate in a recent publication. The phenomena presented evidence to involve lots of physical field such as surface chemistry, haematolology, fluid mechanics, heat transfer, colloids science... All these mechanisms are acting together and produce an axisymetric and reproducible pattern. Dried cellular components are segregated and deposited by a capillary flow. During the evaporation, the system is slowly drying and cracks when stresses are too important leading to the final pattern observed. In this presentation, we will present the mechanisms involved in the formation of crack patterns. The phenomenon presented here with red blood cells as the main colloids involved is very similar to the drying of drop of nanoparticules. We will explain the common point and the differences encountered.

  12. Dropping In a Microgravity Environment (DIME) Contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Students from Sycamore High School in Cincinnati, Ohio (girls), and the COSI Academy, Columbus, Ohio (boys), participated. This image is from a digital still camera; higher resolution is not available.

  13. Control of Drop Motion by Mechanical Vibrations

    NASA Astrophysics Data System (ADS)

    Bestehorn, Michael

    2014-11-01

    Since the first experimental observations of Michael Faraday in 1831 it is known that a vibrating liquid may show an instability of its flat free surface with respect to oscillating regular surface patterns. We study thin liquid films on a horizontal substrate in the long wave approximation. The films are parametrically excited by mechanical horizontal or inclined oscillations. Inertia effects are taken into account and the standard thin film formulation is extended by a second equation for the vertically averaged mass flux. The films can be additionally unstable by Van der Waals forces on a partially wetting substrate, leading to the formation of drops. These drops can be manipulated by the vibrations to move in a desired direction. Linear results based on a damped complex valued Mathieu equation as well as fully nonlinear results using a reduced model will be presented, for more details see.

  14. DROP: Durable Reconnaissance and Observation Platform

    NASA Technical Reports Server (NTRS)

    Parness, Aaron; McKenzie, Clifford F.

    2012-01-01

    Robots have been a valuable tool for providing a remote presence in areas that are either inaccessible or too dangerous for humans. Having a robot with a high degree of adaptability becomes crucial during such events. The adaptability that comes from high mobility and high durability greatly increases the potential uses of a robot in these situations, and therefore greatly increases its usefulness to humans. DROP is a lightweight robot that addresses these challenges with the capability to survive large impacts, carry a usable payload, and traverse a variety of surfaces, including climbing vertical surfaces like wood, stone, and concrete. The platform is crash-proof, allowing it to be deployed in ways including being dropped from an unmanned aerial vehicle or thrown from a large MSL-class (Mars Science Laboratory) rover.

  15. Surface-controlled drop oscillations in space

    NASA Astrophysics Data System (ADS)

    Holt, R. Glynn

    2001-05-01

    A series of experiments probing the effects of surfactants was performed by Bob Apfel and his research group in the 1990s. Several laboratory experiments were carried out in uni-axial acoustic levitators. Two experiments were carried out in a triple-axis levitator called the Drop Physics Module, which was carried on Space Shuttle Columbia as part of the First and Second United States Microgravity Laboratory missions. Liquid drops containing aqueous solutions of soluble surfactants were acoustically positioned and deformed (and in some cases rotated) in order to excite shape mode oscillations. The results of these experiments allowed the inference of surface rheological properties (Gibb's elasticity, surface viscosity coefficients) as functions of surfactant type and concentration. The highlights of this effort will be presented in a semi-technical fashion. [Work supported by NASA.

  16. Pressure Drops Due to Silica Scaling

    SciTech Connect

    Brown, K.L.; Freeston, D.H.; Dimas, Z.O.; Slatter, A.

    1995-01-01

    Experience with reinjection returns in many geothermal fields has prompted a move towards injecting waste fluids at some distance from the production field. This means that often, reinjection pipelines cover very long distances. If the waste water in the pipelines is supersaturated with respect to amorphous silica, then the deposition of silica in these pipelines is almost certain. Although the deposit may be of negligible thickness, the inner surface characteristics of the pipe will be different to those of clean mild steel. During a silica scaling experiment. geothermal brine was passed through a series of pipes of different sizes and over a period of three weeks, silica scale formed on the inner surface. The pressure drop along a distance of approximately 5m was measured by a water manometer in all test pipe sections. Significant pressure drop was observed during this time and can be correlated with the increase in the friction factor of the pipe walls due to silica scaling.

  17. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Here, students from Sycamore High School in Cincinnati, Ohio, help a NASA technician prepare their experiment. This image is from a digital still camera; higher resolution is not available.

  18. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. This is the interior of the Sycamore High School (Cincinnati, Ohio) students' experiment to observe the flame spreading on a 100 percent cotton T-shirt under low-g. This image is from a digital still camera; higher resolution is not available.

  19. Dropping In a Microgravity Environment (DIME) Contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Pictured are students from COSI Academy, Columbus, Ohio and their teacher. The other team was from Sycamore High School in Cincinnati, Ohio. This image is from a digital still camera; higher resolution is not available.

  20. Dropping In a Microgravity Environment (DIME) contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. Here Carol Hodanbosi of the National Center for Microgravity Research and Jose Carrion, a lab mechanic with AKAC, prepare a student experiment package (inside the silver-colored frame) inside the orange-colored drag shield that encloses all experiment hardware. This image is from a digital still camera; higher resolution is not available.

  1. Instrumented drop ball tester for percussion primers

    SciTech Connect

    Woods, C.M.; Robinson, M.A.; Merten, C.W.; Robbins, V.E. ); Begeal, D.R. )

    1991-01-01

    The drop ball tester has historically been used for determining the threshold characteristics of percussion primers. Typically, the data obtained from such a tester show a wide variation with significantly large standard deviations. This requires that the acceptance specifications for primers be fairly lax. To determine how much of the data scatter was due to the tester alone, a drop ball tester was instrumented with a force monitoring gage, velocity capabilities, deflection gages, and a pressure time output measuring system. This paper deals with the basic fundamental physics involved with the tester and presents results of improvements to the tester geometry. Threshold test results are presented, correlating all of the variables measured. 8 refs., 10 figs.

  2. Drop evaporation and triple line dynamics

    NASA Astrophysics Data System (ADS)

    Sobac, Benjamin; Brutin, David; Gavillet, Jerome; Université de Provence Team; Cea Liten Team

    2011-03-01

    Sessile drop evaporation is a phenomenon commonly came across in nature or in industry with cooling, paintings or DNA mapping. However, the evaporation of a drop deposited on a substrate is not completely understood due to the complexity of the problem. Here we investigate, with several nano-coating of the substrate (PTFE, SiOx, SiOc and CF), the influence of the dynamic of the triple line on the evaporation process. The experiment consists in analyzing simultaneously the motion of the triple line, the kinetics of evaporation, the internal thermal motion and the heat and mass transfer. Measurements of temperature, heat-flux and visualizations with visible and infrared cameras are performed. The dynamics of the evaporative heat flux appears clearly different depending of the motion of the triple line

  3. Intermittent head drops: the differential spectrum.

    PubMed

    Antelmi, Elena; Plazzi, Giuseppe; Erro, Roberto; Tinuper, Paolo; Balint, Bettina; Liguori, Rocco; Bhatia, Kailash P

    2016-04-01

    Intermittent Head Drops are episodic head flexion movements that can occur in a number of conditions. Typically, the term has mainly been related to epileptic episodes, but the spectrum of clinical conditions associated with this feature is wide-ranging even if never discussed in detail. By searching the electronic database, we may find that apart from the epileptic conditions, Intermittent Head Drops have been in fact reported in the setting of movement disorders, sleep disorders and even internal medicine disorders, such as Sandifer syndrome. We render an in-depth description of this characteristic phenomenon in different diseases, describing the clinical clues and neurophysiological patterns that may help the clinician to distinguish between the different settings of occurrence. PMID:26085650

  4. Drop impact into a deep pool: vortex shedding and jet formation

    SciTech Connect

    Agbaglah, G.; Thoraval, M. -J.; Thoroddsen, S. T.; Zhang, L. V.; Fezzaa, K.; Deegan, R. D.

    2015-02-01

    One of the simplest splashing scenarios results from the impact of a single drop on a deep pool. The traditional understanding of this process is that the impact generates an axisymmetric sheet-like jet that later breaks up into secondary droplets. Recently it was shown that even this simplest of scenarios is more complicated than expected because multiple jets can be generated from a single impact event and there are transitions in the multiplicity of jets as the experimental parameters are varied. Here, we use experiments and numerical simulations of a single drop impacting on a deep pool to examine the transition from impacts that produce a single jet to those that produce two jets. Using high-speed X-ray imaging methods we show that vortex separation within the drop leads to the formation of a second jet long after the formation of the ejecta sheet. Using numerical simulations we develop a phase diagram for this transition and show that the capillary number is the most appropriate order parameter for the transition.

  5. Alternative Geothermal Power Production Scenarios

    DOE Data Explorer

    Sullivan, John

    2014-03-14

    The information given in this file pertains to Argonne LCAs of the plant cycle stage for a set of ten new geothermal scenario pairs, each comprised of a reference and improved case. These analyses were conducted to compare environmental performances among the scenarios and cases. The types of plants evaluated are hydrothermal binary and flash and Enhanced Geothermal Systems (EGS) binary and flash plants. Each scenario pair was developed by the LCOE group using GETEM as a way to identify plant operational and resource combinations that could reduce geothermal power plant LCOE values. Based on the specified plant and well field characteristics (plant type, capacity, capacity factor and lifetime, and well numbers and depths) for each case of each pair, Argonne generated a corresponding set of material to power ratios (MPRs) and greenhouse gas and fossil energy ratios.

  6. Modeling Evaporation of Drops of Different Kerosenes

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth

    2007-01-01

    A mathematical model describes the evaporation of drops of a hydrocarbon liquid composed of as many as hundreds of chemical species. The model is intended especially for application to any of several types of kerosenes commonly used as fuels. The concept of continuous thermodynamics, according to which the chemical composition of the evaporating multicomponent liquid is described by use of a probability distribution function (PDF). However, the present model is more generally applicable than is its immediate predecessor.

  7. Probable warfarin interaction with menthol cough drops.

    PubMed

    Coderre, Karen; Faria, Claudio; Dyer, Earl

    2010-01-01

    Warfarin is a widely used and effective oral anticoagulant; however, the agent has an extensive drug and food interaction profile. We describe a 46-year-old African-American man who was receiving warfarin for a venous thromboembolism and experienced a decrease in his international normalized ratio (INR). No corresponding reduction had been made in his warfarin dosage, and no changes had been made in his concomitant drug therapy or diet. The patient's INR fell from a therapeutic value of 2.6 (target range 2-3) to 1.6 while receiving a weekly warfarin dose of 50 mg. His INR remained stable at 1.6 for 3 weeks despite incremental increases in his warfarin dose. The patient reported that he had been taking 8-10 menthol cough drops/day due to dry conditions at his workplace during the time period that the INR decreased. Five days after discontinuing the cough drops, his INR increased from 1.6 to 2.9. Over the subsequent 5 weeks, his INR was stabilized at a much lower weekly warfarin dose of 40 mg. Use of the Naranjo adverse drug reaction probability scale indicated that the decreased INR was probably related to the concomitant use of menthol cough drops during warfarin therapy. The mechanism for this interaction may be related to the potential for menthol to affect the cytochrome P450 system as an inducer and inhibitor of certain isoenzymes that would potentially interfere with the metabolism of warfarin. To our knowledge, this is the second case report of an interaction between warfarin and menthol. Patients receiving warfarin should be closely monitored, as they may choose to take over-the-counter products without considering the potential implications, and counseled about a possible interaction with menthol cough drops. PMID:20030479

  8. Low-Pressure-Drop Shutoff Valve

    NASA Technical Reports Server (NTRS)

    Thornborrow, John

    1994-01-01

    Flapper valve remains open under normal flow conditions but closes upon sudden increases to high rate of flow and remains closed until reset. Valve is fluid/mechanical analog of electrical fuse or circuit breaker. Low-pressure-drop shutoff valve contains flapper machined from cylindrical surface. During normal flow conditions, flapper presents small cross section to flow. (Useful in stopping loss of fluid through leaks in cooling systems.)

  9. Diffusion Of Mass In Evaporating Multicomponent Drops

    NASA Technical Reports Server (NTRS)

    Bellan, Josette; Harstad, Kenneth G.

    1992-01-01

    Report summarizes study of diffusion of mass and related phenomena occurring in evaporation of dense and dilute clusters of drops of multicomponent liquids intended to represent fuels as oil, kerosene, and gasoline. Cluster represented by simplified mathematical model, including global conservation equations for entire cluster and conditions on boundary between cluster and ambient gas. Differential equations of model integrated numerically. One of series of reports by same authors discussing evaporation and combustion of sprayed liquid fuels.

  10. Software for emission rate modeling of accidental toxic releases

    SciTech Connect

    Kumar, A.; Vashisth, S.

    1999-08-01

    This book fulfills the need for Section 112(r) of the Clean Air Act Amendments of 1990. This software is based on the guidelines released by the USEPA. It includes manual and proprietary software on CDROM. Contents include release scenario description (two-phase and single-phase choked/unchoked gas release, two-phase pressurized and refrigerated liquid release, single-phase high and low volatility liquid release); emission rate model development for each release class; software design and software evaluation and application.

  11. Excess equimolar radius of liquid drops.

    PubMed

    Horsch, Martin; Hasse, Hans; Shchekin, Alexander K; Agarwal, Animesh; Eckelsbach, Stefan; Vrabec, Jadran; Müller, Erich A; Jackson, George

    2012-03-01

    The curvature dependence of the surface tension is related to the excess equimolar radius of liquid drops, i.e., the deviation of the equimolar radius from the radius defined by the macroscopic capillarity approximation. Based on the Tolman [J. Chem. Phys. 17, 333 (1949)] approach and its interpretation by Nijmeijer et al. [J. Chem. Phys. 96, 565 (1991)], the surface tension of spherical interfaces is analyzed in terms of the pressure difference due to curvature. In the present study, the excess equimolar radius, which can be obtained directly from the density profile, is used instead of the Tolman length. Liquid drops of the truncated and shifted Lennard-Jones fluid are investigated by molecular dynamics simulation in the canonical ensemble, with equimolar radii ranging from 4 to 33 times the Lennard-Jones size parameter σ. In these simulations, the magnitude of the excess equimolar radius is shown to be smaller than σ/2. This suggests that the surface tension of liquid drops at the nanometer length scale is much closer to that of the planar vapor-liquid interface than reported in studies based on the mechanical route. PMID:22587106

  12. Organization of microbeads in Leidenfrost drops.

    PubMed

    Maquet, Laurent; Colinet, Pierre; Dorbolo, Stéphane

    2014-06-21

    We investigated the organization of micrometric hydrophilic beads (glass or basalt) immersed in Leidenfrost drops. Starting from a large volume of water compared to the volume of the beads, while the liquid evaporates, we observed that the grains are eventually trapped at the interface of the droplet and accumulate. At a moment, the grains entirely cover the droplet. We measured the surface area at this moment as a function of the total mass of particles inserted in the droplet. We concluded that the grains form a monolayer around the droplet assuming (i) that the packing of the beads at the surface is a random close packing and (ii) that the initial surface of the drop is larger than the maximum surface that the beads can cover. Regarding the evaporation dynamics, the beads are found to reduce the evaporation rate of the drop. The slowdown of the evaporation is interpreted as being the consequence of the dewetting of the particles located at the droplet interface which makes the effective surface of evaporation smaller. As a matter of fact, contact angles of the beads with the water deduced from the evaporation rates are consistent with contact angles of beads directly measured at a flat air-water interface of water in a container. PMID:24705688

  13. Dropping In a Microgravity Environment (DIME) Contest

    NASA Technical Reports Server (NTRS)

    2001-01-01

    The first NASA Dropping In a Microgravity Environment (DIME) student competition pilot project came to a conclusion at the Glenn Research Center in April 2001. The competition involved high-school student teams who developed the concept for a microgravity experiment and prepared an experiment proposal. The two student teams - COSI Academy, sponsored by the Columbus Center of Science and Industry, and another team from Cincinnati, Ohio's Sycamore High School, designed a microgravity experiment, fabricated the experimental apparatus, and visited NASA Glenn to operate their experiment in the 2.2 Second Drop Tower. NASA and contractor personnel who conducted the DIME activity with the students. Shown (L-R) are: Daniel Dietrich (NASA) mentor for Sycamore High School team), Carol Hodanbosi (National Center for Microgravity Research; DIME staff), Jose Carrion (GRC Akima, drop tower technician), Dennis Stocker (NASA; DIME staff), Richard DeLombard (NASA; DIME staff), Sandi Thompson (NSMR sabbatical teacher; DIME staff), Peter Sunderland (NCMR, mentor for COSI Academy student team), Adam Malcolm (NASA co-op student; DIME staff). This image is from a digital still camera; higher resolution is not available.

  14. Ultrasonic characterization of single drops of liquids

    DOEpatents

    Sinha, D.N.

    1998-04-14

    Ultrasonic characterization of single drops of liquids is disclosed. The present invention includes the use of two closely spaced transducers, or one transducer and a closely spaced reflector plate, to form an interferometer suitable for ultrasonic characterization of droplet-size and smaller samples without the need for a container. The droplet is held between the interferometer elements, whose distance apart may be adjusted, by surface tension. The surfaces of the interferometer elements may be readily cleansed by a stream of solvent followed by purified air when it is desired to change samples. A single drop of liquid is sufficient for high-quality measurement. Examples of samples which may be investigated using the apparatus and method of the present invention include biological specimens (tear drops; blood and other body fluid samples; samples from tumors, tissues, and organs; secretions from tissues and organs; snake and bee venom, etc.) for diagnostic evaluation, samples in forensic investigations, and detection of drugs in small quantities. 5 figs.

  15. Oxygen transfer at low drop weirs.

    SciTech Connect

    Kim, J.; Walters, R. W.; Environmental Research; Gonzaga Univ.

    2001-07-01

    Oxygen transfer into water at low-drop weirs was studied by using a prototype-scale, recirculating hydraulic flume with a weir width of 0.61 m, and a downstream channel width of 1.22 m. An enhanced-oxygen environment was used to maintain sufficient difference between saturation and upstream dissolved oxygen concentrations to reduce the experimental uncertainty. The variation in the deficit ratio r as a function of tailwater depth H was evaluated by using unit discharges q of 167, 334, and 502 m{sup 3}/hr{center_dot}m and weir heights W of 0.54, 1.04, and 1.36 m. A semitheoretical equation for predicting r as a function of jet Froude number F{sub J}, drop height h, and H was fitted to observed values by nonlinear regression analysis. An assumed value of 0.667 for maximum H/h (found in the literature) proved acceptable. We concluded that tailwater depths are important to predict oxygen transfer at low-drop weirs, but that designing for optimum tailwater depth to maximize oxygen transfer may not be as important as was previously thought, because large optimum ranges for H/h were observed in this study.

  16. Drop floating on a granular raft

    NASA Astrophysics Data System (ADS)

    Jambon-Puillet, Etienne; Josserand, Christophe; Protiere, Suzie

    2015-11-01

    When a droplet comes in contact with a bath of the same liquid, it coalesces to minimize the surface energy. This phenomenon reduces emulsion stability and is usually fought with surfactant molecules. Another way to slow down coalescence is to use colloidal solid particles. In this case the particles spontaneously migrate to the interface to form ``Pickering'' emulsions and act as a barrier between droplets. Here we use dense, large particles (~ 500 μm) which form a monolayer at an oil/water interface that we call a granular raft. When a droplet is placed on top of such a raft, for a given set of particle properties (contact angle/size), the raft prevents coalescence indefinitely. However, in contrast to what happens when a droplet is placed on a hydrophobic surface and never wets the surface, here the droplet is strongly anchored to the raft and deforms it. We will use this specific configuration to probe the mechanical response of the granular raft: by controlling the droplet volume we can impose tensile or compressive stresses. Finally we will show that the drop, spherical at first, slowly takes a more complex shape as it's volume increases. This shape is not reversible as the drop volume is decreased. The drop can become oblate or prolate with wrinkling of the raft.

  17. Viscosity Measurement using Drop Coalescence in Microgravity

    NASA Technical Reports Server (NTRS)

    Antar, Basil N.; Ethridge, Edwin; Maxwell, Daniel

    1999-01-01

    We present in here details of a new method, using drop coalescence, for application in microgravity environment for determining the viscosity of highly viscous undercooled liquids. The method has the advantage of eliminating heterogeneous nucleation at container walls caused by crystallization of undercooled liquids during processing. Also, due to the rapidity of the measurement, homogeneous nucleation would be avoided. The technique relies on both a highly accurate solution to the Navier-Stokes equations as well as on data gathered from experiments conducted in near zero gravity environment. The liquid viscosity is determined by allowing the computed free surface shape relaxation time to be adjusted in response to the measured free surface velocity of two coalescing drops. Results are presented from two validation experiments of the method which were conducted recently on board the NASA KC-135 aircraft. In these tests the viscosity of a highly viscous liquid, such as glycerine at different temperatures, was determined to reasonable accuracy using the liquid coalescence method. The experiments measured the free surface velocity of two glycerine drops coalescing under the action of surface tension alone in low gravity environment using high speed photography. The free surface velocity was then compared with the computed values obtained from different viscosity values. The results of these experiments were found to agree reasonably well with the calculated values.

  18. Surfactant and nonlinear drop dynamics in microgravity

    NASA Astrophysics Data System (ADS)

    Jankovsky, Joseph Charles

    2000-11-01

    Large amplitude drop dynamics in microgravity were conducted during the second United States Microgravity Laboratory mission carried onboard the Space Shuttle Columbia (20 October-5 November 1995). Centimeter- sized drops were statically deformed by acoustic radiation pressure and released to oscillate freely about a spherical equilibrium. Initial aspect ratios of up to 2.0 were achieved. Experiments using pure water and varying aqueous concentrations of Triton-X 100 and bovine serum albumin (BSA) were performed. The axisymmetric drop shape oscillations were fit using the degenerate spherical shape modes. The frequency and decay values of the fundamental quadrupole and fourth order shape mode were analyzed. Several large amplitude nonlinear oscillation dynamics were observed. Shape entrainment of the higher modes by the fundamental quadrupole mode occurred. Amplitude- dependent effects were observed. The nonlinear frequency shift, where the oscillation frequency is found to decrease with larger amplitudes, was largely unaffected by the presence of surfactants. The percentage of time spent in the prolate shape over one oscillation cycle was found to increase with oscillation amplitude. This prolate shape bias was also unaffected by the addition of surfactants. These amplitude-dependent effects indicate that the nonlinearities are a function of the bulk properties and not the surface properties. BSA was found to greatly enhance the surface viscoelastic properties by increasing the total damping of the oscillation, while Triton had only a small influence on damping. The surface concentration of BSA was found to be diffusion-controlled over the time of the experiments, while the Triton diffusion rate was very rapid. Using the experimental frequency and decay values, the suface viscoelastic properties of surface dilatational viscosity ( ks ) and surface shear viscosity ( ms ) were found for varying surfactant concentrations using the transcendental equation of Lu & Apfel (1991) and Tian et al. (1997). Values for Triton for concentrations of 0.017 to 2 CMC range from 0.01 to 0.05 surface poise (sp) for ks . For BSA, the fitting of the experimental data was highly sensitive to ms over a wide range of ks . Setting ks = 1 sp for 1 CMC drops ms , was found to increase from 0.07 to 0.28 sp linearly with the square root of time, indicating that surface shear viscosity is proportional to the surface concentration in the diffusion-controlled regime. The same time dependence was found for 2 CMC drops. However, the fitted shear viscosity was nearly half that of the 1 CMC concentration over the same time frame.

  19. Laplacian drop shapes and effect of random perturbations on accuracy of surface tension measurement for different drop constellations.

    PubMed

    Saad, Sameh M I; Neumann, A Wilhelm

    2015-08-01

    Theoretical drop shapes are calculated for three drop constellations: pendant drops, constrained sessile drops, and unconstrained sessile drops. Based on total Gaussian curvature, shape parameter and critical shape parameter are discussed as a function of different drop sizes and surface tensions. The shape parameter is linked to physical parameters for every drop constellation. The as yet unavailable detailed dimensional analysis for the unconstrained sessile drop is presented. Results show that the unconstrained sessile drop shape depends on a dimensionless volume term and the contact angle. Random perturbations are introduced and the accuracy of surface tension measurement is assessed for precise and perturbed profiles of the three drop constellations. It is concluded that pendant drops are the best method for accurate surface tension measurement, followed by constrained sessile drops. The unconstrained sessile drops come last because they tend to be more spherical at low and moderate contact angles. Of course, unconstrained sessile drops are the only option if contact angles are to be measured. PMID:25466689

  20. Future Scenarios and Environmental Education

    ERIC Educational Resources Information Center

    Kopnina, Helen

    2014-01-01

    This article explores a number of questions about visions of the future and their implications for environmental education (EE). If the future were known, what kind of actions would be needed to maintain the positive aspects and reverse the negative ones? How could these actions be translated into the aims of EE? Three future scenarios are

  1. Future Scenarios and Environmental Education

    ERIC Educational Resources Information Center

    Kopnina, Helen

    2014-01-01

    This article explores a number of questions about visions of the future and their implications for environmental education (EE). If the future were known, what kind of actions would be needed to maintain the positive aspects and reverse the negative ones? How could these actions be translated into the aims of EE? Three future scenarios are…

  2. Transportation scenarios for risk analysis.

    SciTech Connect

    Weiner, Ruth F.

    2010-09-01

    Transportation risk, like any risk, is defined by the risk triplet: what can happen (the scenario), how likely it is (the probability), and the resulting consequences. This paper evaluates the development of transportation scenarios, the associated probabilities, and the consequences. The most likely radioactive materials transportation scenario is routine, incident-free transportation, which has a probability indistinguishable from unity. Accident scenarios in radioactive materials transportation are of three different types: accidents in which there is no impact on the radioactive cargo, accidents in which some gamma shielding may be lost but there is no release of radioactive material, and accident in which radioactive material may potentially be released. Accident frequencies, obtainable from recorded data validated by the U.S. Department of Transportation, are considered equivalent to accident probabilities in this study. Probabilities of different types of accidents are conditional probabilities, conditional on an accident occurring, and are developed from event trees. Development of all of these probabilities and the associated highway and rail accident event trees are discussed in this paper.

  3. Ultra-Perfect Sorting Scenarios

    NASA Astrophysics Data System (ADS)

    Ouangraoua, Aïda; Bergeron, Anne; Swenson, Krister M.

    Perfection has been used as a criteria to select rearrangement scenarios since 2004. However, there is a fundamental bias towards extant species in the original definition: ancestral species are not bound to perfection. Here we develop a new theory of perfection that takes an egalitarian view of species, and apply it to the complex evolution of mammal chromosome X.

  4. Space resources. Volume 1: Scenarios

    NASA Technical Reports Server (NTRS)

    Mckay, Mary Fae (Editor); Mckay, David S. (Editor); Duke, Michael B. (Editor)

    1992-01-01

    A number of possible future paths for space exploration and development are presented. The topics covered include the following: (1) the baseline program; (2) alternative scenarios utilizing nonterrestrial resources; (3) impacts of sociopolitical conditions; (4) common technologies; and issues for further study.

  5. Detecting spatiotemporal clusters of accidental poisoning mortality among Texas counties, U.S., 1980 2001

    PubMed Central

    Nkhoma, Ella T; Ed Hsu, Chiehwen; Hunt, Victoria I; Harris, Ann Marie

    2004-01-01

    Background Accidental poisoning is one of the leading causes of injury in the United States, second only to motor vehicle accidents. According to the Centers for Disease Control and Prevention, the rates of accidental poisoning mortality have been increasing in the past fourteen years nationally. In Texas, mortality rates from accidental poisoning have mirrored national trends, increasing linearly from 1981 to 2001. The purpose of this study was to determine if there are spatiotemporal clusters of accidental poisoning mortality among Texas counties, and if so, whether there are variations in clustering and risk according to gender and race/ethnicity. The Spatial Scan Statistic in combination with GIS software was used to identify potential clusters between 1980 and 2001 among Texas counties, and Poisson regression was used to evaluate risk differences. Results Several significant (p < 0.05) accidental poisoning mortality clusters were identified in different regions of Texas. The geographic and temporal persistence of clusters was found to vary by racial group, gender, and race/gender combinations, and most of the clusters persisted into the present decade. Poisson regression revealed significant differences in risk according to race and gender. The Black population was found to be at greatest risk of accidental poisoning mortality relative to other race/ethnic groups (Relative Risk (RR) = 1.25, 95% Confidence Interval (CI) = 1.24 1.27), and the male population was found to be at elevated risk (RR = 2.47, 95% CI = 2.45 2.50) when the female population was used as a reference. Conclusion The findings of the present study provide evidence for the existence of accidental poisoning mortality clusters in Texas, demonstrate the persistence of these clusters into the present decade, and show the spatiotemporal variations in risk and clustering of accidental poisoning deaths by gender and race/ethnicity. By quantifying disparities in accidental poisoning mortality by place, time and person, this study demonstrates the utility of the spatial scan statistic combined with GIS and regression methods in identifying priority areas for public health planning and resource allocation. PMID:15509301

  6. Modeling of drop breakup in the bag breakup regime

    NASA Astrophysics Data System (ADS)

    Wang, C.; Chang, S.; Wu, H.; Xu, J.

    2014-04-01

    Several analytic models for predicting the drop deformation and breakup have been developed over the last three decades, but modeling drop breakup in the bag-type regime is less reported. In this Letter, a breakup model has been proposed to predict the drop deformation length and breakup time in the bag-type breakup regime in a more accurate manner. In the present model, the drop deformation which is approximately as the displacement of the centre of mass (c. m.) along the axis located at the centre of the drop, and the movement of c. m. is obtained by solving the pressure balance equation. The effects of the drop deformation on the drop external aerodynamic force are considered in this model. Drop breakup occurs when the deformation length reaches the maximum value and the maximum deformation length is a function of Weber number. The performance and applicability of the proposed breakup model are tested against the published experimental data.

  7. Flow visualization and characterization of evaporating liquid drops

    NASA Technical Reports Server (NTRS)

    Chao, David F. (Inventor); Zhang, Nengli (Inventor)

    2004-01-01

    An optical system, consisting of drop-reflection image, reflection-refracted shadowgraphy and top-view photography, is used to measure the spreading and instant dynamic contact angle of a volatile-liquid drop on a non-transparent substrate. The drop-reflection image and the shadowgraphy is shown by projecting the images of a collimated laser beam partially reflected by the drop and partially passing through the drop onto a screen while the top view photograph is separately viewed by use of a camera video recorder and monitor. For a transparent liquid on a reflective solid surface, thermocapillary convection in the drop, induced by evaporation, can be viewed nonintrusively, and the drop real-time profile data are synchronously recorded by video recording systems. Experimental results obtained from this technique clearly reveal that evaporation and thermocapillary convection greatly affect the spreading process and the characteristics of dynamic contact angle of the drop.

  8. Tandem wheel drop-legs for standard truck trailer

    NASA Technical Reports Server (NTRS)

    Cantwell, W.; Selstad, R.

    1970-01-01

    Tandem wheel drop-leg device provides a semitrailer with fore and aft mobility that allows it to be moved without a prime mover. The modified drop-legs have trunnion dual wheels and an adjustable brace.

  9. Drop-by-drop chemical reaction and sample introduction for capillary electrophoresis.

    PubMed

    Chen, Fengming; Rang, Ying; Weng, Ying; Lin, Luyao; Zeng, Hulie; Nakajim, Hizuru; Lin, Jin-Ming; Uchiyama, Katsumi

    2015-06-21

    In this paper, we report a novel sample introduction and chemical reaction strategy by drop-by-drop inkjet injection for an electrophoretically mediated microanalysis (EMMA). This method makes it possible to achieve an on-line introduction of reactant solutions by alternately ejecting small plugs, with an overlapping region of the plugs for mixing the reactants by electrophoresis, supporting chemical reactions, followed by electrophoretic separation of the final compounds. As a proof-of-concept of the method, the EMMA of an inkjetted mixture of 4-fluoro-7-nitrobenzofurazan (NBD-F) and amino acids was carried out as a model chemical reaction. The product NBD-amino acids were quantified by detection with laser induced fluorescence. The optimal conditions for the procedure were: inkjet driving voltage: +40-44 V; pulse width: 20-24 μs; drop-by-drop injection of reactant solutions: alternately 2 drops × 25 times for the amino acid solution and the NBD-F solution; zone overlapping voltage and time: 3 kV and 2 s; incubation time after overlapping: 5 min; separation voltage: 18 kV. Under the optimized conditions, a significant enhancement in sensitivity and a sensitive quantitative analysis were realized. The results obtained were comparable with those using the off-line labeling method. This method is rapid, cost-effective, and readily automated for EMMA. PMID:25728632

  10. Fate of accidental symmetries of the relativistic hydrogen atom in a spherical cavity

    NASA Astrophysics Data System (ADS)

    Al-Hashimi, M. H.; Shalaby, A. M.; Wiese, U.-J.

    2015-11-01

    The non-relativistic hydrogen atom enjoys an accidental SO(4) symmetry, that enlarges the rotational SO(3) symmetry, by extending the angular momentum algebra with the Runge-Lenz vector. In the relativistic hydrogen atom the accidental symmetry is partially lifted. Due to the Johnson-Lippmann operator, which commutes with the Dirac Hamiltonian, some degeneracy remains. When the non-relativistic hydrogen atom is put in a spherical cavity of radius R with perfectly reflecting Robin boundary conditions, characterized by a self-adjoint extension parameter γ, in general the accidental SO(4) symmetry is lifted. However, for R =(l + 1) (l + 2) a (where a is the Bohr radius and l is the orbital angular momentum) some degeneracy remains when γ = ∞ or γ =2/R. In the relativistic case, we consider the most general spherically and parity invariant boundary condition, which is characterized by a self-adjoint extension parameter. In this case, the remnant accidental symmetry is always lifted in a finite volume. We also investigate the accidental symmetry in the context of the Pauli equation, which sheds light on the proper non-relativistic treatment including spin. In that case, again some degeneracy remains for specific values of R and γ.

  11. Patterns and Trends in Accidental Poisoning Deaths: Pennsylvania’s Experience 1979-2014

    PubMed Central

    Balmert, Lauren C.; Buchanich, Jeanine M.; Pringle, Janice L.; Williams, Karl E.; Burke, Donald S.; Marsh, Gary M.

    2016-01-01

    Introduction The purpose of this study was to examine county and state-level accidental poisoning mortality trends in Pennsylvania from 1979 to 2014. Methods Crude and age-adjusted death rates were formed for age group, race, sex, and county for accidental poisonings (ICD 10 codes X40-X49) from 1979 to 2014 for ages 15+ using the Mortality and Population Data System housed at the University of Pittsburgh. Rate ratios were calculated comparing rates from 1979 to 2014, overall and by sex, age group, and race. Joinpoint regression was used to detect statistically significant changes in trends of age-adjusted mortality rates. Results Rate ratios for accidental poisoning mortality in Pennsylvania increased more than 14-fold from 1979 to 2014. The largest rate ratios were among 35–44 year olds, females, and White adults. The highest accidental poisoning mortality rates were found in the counties of Southwestern Pennsylvania, those surrounding Philadelphia, and those in Northeast Pennsylvania near Scranton. Conclusions The patterns and locations of accidental poisoning mortality by race, sex, and age group provide direction for interventions and policy makers. In particular, this study found the highest rate ratios in PA among females, whites, and the age group 35–44. PMID:26963396

  12. Accidental Release of Chlorine from a Storage Facility and an On-Site Emergency Mock Drill: A Case Study

    PubMed Central

    Soman, Ambalathumpara Raman; Sundararaj, Gopalswamy

    2015-01-01

    In the current industrial scenario there is a serious need for formulating strategies to handle hazardous substances in the safest way. Manufacture, storage, and use of hazardous substances pose a serious risk to industry, people, and the environment. Accidental release of toxic chemicals can lead to emergencies. An emergency response plan (ERP) is inevitable to minimize the adverse effects of such releases. The on-site emergency plan is an integral component of any process safety and risk management system. This paper deals with an on-site emergency response plan for a chlorine manufacturing industry. It was developed on the basis of a previous study on chlorine release and a full scale mock drill has been conducted for testing the plan. Results indicated that properly trained personnel can effectively handle each level of incidents occurring in the process plant. As an extensive guideline to the district level government authorities for off-site emergency planning, risk zone has also been estimated with reference to a chlorine exposure threshold of 3 ppm. PMID:26171416

  13. Impact dynamics of oxidized liquid metal drops

    NASA Astrophysics Data System (ADS)

    Xu, Qin; Brown, Eric; Jaeger, Heinrich M.

    2013-04-01

    With exposure to air, many liquid metals spontaneously generate an oxide layer on their surface. In oscillatory rheological tests, this skin is found to introduce a yield stress that typically dominates the elastic response but can be tuned by exposing the metal to hydrochloric acid solutions of different concentration. We systematically studied the normal impact of eutectic gallium-indium (eGaIn) drops under different oxidation conditions and show how this leads to two different dynamical regimes. At low impact velocity (or low Weber number), eGaIn droplets display strong recoil and rebound from the impacted surface when the oxide layer is removed. In addition, the degree of drop deformation or spreading during impact is controlled by the oxide skin. We show that the scaling law known from ordinary liquids for the maximum spreading radius as a function of impact velocity can still be applied to the case of oxidized eGaIn if an effective Weber number We is employed that uses an effective surface tension factoring in the yield stress. In contrast, no influence on spreading from different oxidations conditions is observed for high impact velocity. This suggests that the initial kinetic energy is mostly damped by bulk viscous dissipation. Results from both regimes can be collapsed in an impact phase diagram controlled by two variables, the maximum spreading factor Pm=R0/Rm, given by the ratio of initial to maximum drop radius, and the impact number K=We/Re4/5, which scales with the effective Weber number We as well as the Reynolds number Re. The data exhibit a transition from capillary to viscous behavior at a critical impact number Kc≈0.1.

  14. Pressure Drop in Radiator Air Tubes

    NASA Technical Reports Server (NTRS)

    Parsons, S R

    1921-01-01

    This report describes a method for measuring the drop in static pressure of air flowing through a radiator and shows (1) a reason for the discrepancy noted by various observers between head resistance and drop in pressure; (2) a difference in degree of contraction of the jet in entering a circular cell and a square cell; (3) the ratio of internal frictional resistance to total head resistance for two representative types; (4) the effect of smoothness of surface on pressure gradient; and (5) the effects of supplying heat to the radiator on pressure gradient. The fact that the pressure gradients are found to be approximately proportional to the square of the rate of flow of air appears to indicate turbulent flow, even in the short tubes of the radiator. It was found that the drop in the static pressure in the air stream through a cellular radiator and the pressure gradient in the air tubes are practically proportional to the square of the air flow in a given air density; that the difference between the head resistance per unit area and the fall of static pressure through the air tubes in radiators is apparent rather than real; and that radiators of different types differ widely in the amount of contraction of the jet at entrance. The frictional resistance was found to vary considerably, and in one case to be two-thirds of the head resistance in the type using circular cells and one-half of the head resistance of the radiator type using square cells of approximately the same dimensions.

  15. Improved Refractometer for Measuring Temperatures of Drops

    NASA Technical Reports Server (NTRS)

    Naqwi, Amir A.

    2004-01-01

    The Dual Rainbow refractometer is an enhanced version of the Rainbow refractometer, which is added to, and extends the capabilities of, a phase Doppler particle analyzer (PDPA). A PDPA utilizes pairs of laser beams to measure individual components of velocity and sizes of drops in a spray. The Rainbow-refractometer addition measures the temperatures of individual drops. The designs of prior versions of the Rainbow refractometer have required substantial modifications of PDPA transmitting optics, plus dedicated lasers as sources of illumination separate from, and in addition to, those needed for PDPA measurements. The enhancement embodied in the Dual Rainbow refractometer eliminates the need for a dedicated laser and confers other advantages as described below. A dedicated laser is no longer needed because the Dual Rainbow refractometer utilizes one of the pairs of laser beams already present in a PDPA. Hence, the design of the Dual Rainbow refractometer simplifies the task of upgrading PDPA hardware to enable measurement of temperature. Furthermore, in a PDPA/Dual Rainbow refractometer system, a single argon-ion laser with three main wavelengths can be used to measure the temperatures, sizes, and all three components of velocity (in contradistinction to only two components of velocity in a prior PDPA/Rainbow refractometer system). In order to enable the Dual Rainbow refractometer to utilize a pair of PDPA laser beams, it was necessary to (1) find a location for the refractometer receiver, such that the combined rainbow patterns of two laser beams amount to a pattern identical to that of a single beam, (2) adjust the polarization of the two beams to obtain the strongest rainbow pattern, and (3) find a location for the PDPA receiver to obtain a linear relationship between the measured phase shift and drop size.

  16. Protocol of Blood Serum Eye Drops.

    PubMed

    Katsakoulas, Ioannis; Lougovoi, Claudia; Paraskevopoulou, Penelope; Vougioukas, Nikolaos

    2015-01-01

    Keratoconjunctivitis sicca is one of the most frequent diagnoses for seeking eye care. Accumulated evidence over the past three decades has revealed a significant contribution of several molecules contained in tears at the homeostasis of the epithelium of the ocular surface. Therefore, autologous blood serum in the form of eye drops can provide substantial help in the management of keratoconjunctivitis sicca. Also making this a favorable treatment for keratoconjunctivitis sicca is the fact that this approach has become an insurance-covered benefit in some countries. This report demonstrates a formulation of blood serum eye drops with the purpose of providing an alternative to the marked absence of a universally established protocol. Exclusion criteria, equipment, preservation, dosage, duration, and guidelines for patients are described. Also included are details on the treatment of one representative embodiment. All (pre-/post-)analytical considerations and the total cost are addressed. Outcome measures such as Schirmer' s test, break up time, and Ocular Surface Disease Index score are recorded before treatment, at 1 and 2 months, ideally as monotherapy with 100% serum q.i.d. Blood serum isolated under aseptic conditions maintained throughout is delivered as a ready-to-use formulation to the patient. Serum eye drops should be included in the modern armamentarium against keratoconjunctivitis sicca, and, hopefully, their eventual widespread application will result in coverage by most if not all insurance funds. The implementation described contributes to the hopeful establishment of a standardized protocol and provides a potentially benefit of a low-cost, applicable treatment of the ocular epithelium without side effects. PMID:26714366

  17. Exploring NASA Human Spaceflight and Pioneering Scenarios

    NASA Technical Reports Server (NTRS)

    Zapata, Edgar; Wilhite, Alan

    2015-01-01

    The life cycle cost analysis of space exploration scenarios is explored via a merger of (1) scenario planning, separating context and (2) modeling and analysis of specific content. Numerous scenarios are presented, leading to cross-cutting recommendations addressing life cycle costs, productivity, and approaches applicable to any scenarios. Approaches address technical and non-technical factors.

  18. ``Water Drops'' Essays Available for Public Radio

    NASA Astrophysics Data System (ADS)

    Black, Peter E.

    2007-11-01

    ``Water Drops'' are 90-second essays on water science, hydrology, culture, history, organizations, law, and policy that have aired weekly on radio station WRVO-FM in Oswego, N.Y., since January 2006. Created for the lay public with a basic understanding of Earth science, the 133 essays now are available on Public Radio Exchange (http://www.prx.org) for free use by public radio stations, according to terms set forth at the Exchange Web site that include citing appropriate credits. If aired weekly, there are enough essays for 2.5 years of radio programming.

  19. Predicting Pressure Drop In Porous Materials

    NASA Technical Reports Server (NTRS)

    Lawing, Pierce L.

    1990-01-01

    Theory developed to predict drop in pressure based on drag of individual fibers. Simple correlation method for data also developed. Helps in predicting flow characteristics of many strain-isolation pad (SIP) glow geometries in Shuttle Orbiter tile system. Also helps in predicting venting characteristics of tile assemblies during ascent and leakage of hot gas under tiles during descent. Useful in study of mechanics of flows through fibrous and porous media, and procedures applicable to purged fiberglass insulation, dialysis filters, and other fibrous and porous media.

  20. Naval Waste Package Drop With Emplacement Pallet

    SciTech Connect

    D.G. McLenzie

    2005-08-04

    The objective of this calculation was to determine the structural responses of the Emplacement Pallet and Naval Long Waste Package (WP) to drops from their highest possible lift heights. The scope of this document was limited to reporting the calculation results in terms of maximum stress intensities. The Naval Long WP is classified as Quality Level 1 (Ref 12, page 7, Table 1). The Emplacement Pallet is classified as Quality Level 2 (Ref. 19, page 7, Table 1). Therefore, this calculation is subject to the requirements of the Quality Assurance Requirements and Description (Ref. 11). AP-3.12Q, Calculations, was used to perform the calculation and develop the document (Ref. 3).

  1. Drop Testing of DOE Spent Nuclear Fuel Canisters

    SciTech Connect

    S. D. Snow; D. K. Morton; T. E. Rahl; R. K. Blandford; T. J. Hill

    2005-07-01

    The National Spent Nuclear Fuel Program (NSNFP) at the Idaho National Engineering and Environmental Laboratory INEEL) prepared four representative Department of Energy DOE) spent nuclear fuel (SNF) canisters for the purpose of drop testing. The first two canisters represented a modified 24- inch diameter standardized DOE SNF canister and the second two canisters represented the Hanford Multi-Canister Overpack MCO). The modified canisters and internals were constructed and assembled at the INEEL. The MCO internal weights were fabricated at the INEEL and assembled into two MCOs at Hanford and later shipped to the INEEL for drop test preparation. Drop testing of these four canisters was completed in August 2004 at Sandia National Laboratories. The modified canisters were dropped from 30 feet onto a flat, essentially unyielding surface, with the canisters oriented at 45 degrees and 70 degrees off-vertical at impact. One representative MCO was dropped from 23 feet onto the same flat surface, oriented vertically at impact. The second representative MCO was dropped onto the flat surface from 2 feet oriented at 60 degrees off-vertical. These drop heights and orientations were chosen to meet or exceed the Yucca Mountain repository drop criteria. This paper discusses the comparison of deformations between the actual dropped canisters and those predicted by pre-drop and limited post-drop finite element evaluations performed using ABAQUS/Explicit. Post-drop containment of all four canisters, demonstrated by way of helium leak testing, is also discussed.

  2. Pendant-Drop Surface-Tension Measurement On Molten Metal

    NASA Technical Reports Server (NTRS)

    Man, Kin Fung; Thiessen, David

    1996-01-01

    Method of measuring surface tension of molten metal based on pendant-drop method implemented in quasi-containerless manner and augmented with digital processing of image data. Electrons bombard lower end of sample rod in vacuum, generating hanging drop of molten metal. Surface tension of drop computed from its shape. Technique minimizes effects of contamination.

  3. Thermocapillary Migration and Interactions of Bubbles and Drops

    NASA Technical Reports Server (NTRS)

    Balasubramaniam, R.; Lacy, Claud E.; Wozniak, Guenter; Subramanian, R. Shankar

    1996-01-01

    When a drop or bubble is placed in another fluid and subjected to the action of a temperature gradient, the drop will move. Such motion is a direct consequence of the variation of interfacial tension with temperature, and is termed thermocapillary migration. This paper discusses results from experiments conducted in reduced gravity on the thermocapillary motion of bubbles and drops.

  4. Delayed Frost Growth on Jumping-Drop Superhydrophobic Surfaces

    SciTech Connect

    Boreyko, Jonathan B; Collier, Pat

    2013-01-01

    Self-propelled jumping drops are continuously removed from a condensing superhydrophobic surface to enable a micrometric steady-state drop size. Here, we report that subcooled condensate on a chilled superhydrophobic surface are able to repeatedly jump off the surface before heterogeneous ice nucleation occurs. Frost still forms on the superhydrophobic surface due to ice nucleation at neighboring edge defects, which eventually spreads over the entire surface via an inter-drop frost wave. The growth of this inter-drop frost front is shown to be up to three times slower on the superhydrophobic surface compared to a control hydrophobic surface, due to the jumping-drop effect dynamically minimizing the average drop size and surface coverage of the condensate. A simple scaling model is developed to relate the success and speed of inter-drop ice bridging to the drop size distribution. While other reports of condensation frosting on superhydrophobic surfaces have focused exclusively on liquid-solid ice nucleation for isolated drops, these findings reveal that the growth of frost is an inter-drop phenomenon that is strongly coupled to the wettability and drop size distribution of the surface. A jumping-drop superhydrophobic condenser was found to be superior to a conventional dropwise condenser in two respects: preventing heterogeneous ice nucleation by continuously removing subcooled condensate, and delaying frost growth by minimizing the success of interdrop ice bridge formation.

  5. Coalescence, evaporation and particle deposition of consecutively printed colloidal drops

    NASA Astrophysics Data System (ADS)

    Chhasatia, Viral; Yang, Xin; Shah, Jaymeen; Sun, Ying

    2012-11-01

    In applications such as inkjet printing and spray deposition, colloid drops are often used as building blocks for line and pattern printing where their interactions play important roles in determining the deposition morphology and properties. In this study, the particle deposition dynamics of two consecutively printed evaporating colloidal drops is examined using a fluorescence microscope and a synchronized side-view camera. The results show that the relaxation time of the water-air interface of the merged drop is shorter than that of a single drop impacting on a dry surface. It is also found that both morphology and particle distribution uniformity of the deposit change significantly with varying jetting delay and spatial spacing between two drops. As the drop spacing increases while keeping jetting delay constant, the circularity of the coalesced drop reduces. For the regime where the time scale for drop evaporation is comparable with the relaxation time scale for two drops to completely coalesce, the capillary flow induced by the local curvature variation of the air-water interface redistributes particles inside a merged drop, causing suppression of the coffee-ring effect for the case of a high jetting frequency while resulting in a region of particle accumulation in the middle of the merged drop at a low jetting frequency. By tuning the interplay of wetting, evaporation, capillary relaxation, and particle assembly, the deposition morphology of consecutively printed colloidal drops can be controlled.

  6. 14 CFR 29.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Reserve energy absorption drop test. 29.727 Section 29.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....727 Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted...

  7. 14 CFR 27.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Reserve energy absorption drop test. 27.727 Section 27.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted as...

  8. 14 CFR 29.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Reserve energy absorption drop test. 29.727 Section 29.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....727 Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted...

  9. 14 CFR 29.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Reserve energy absorption drop test. 29.727 Section 29.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....727 Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted...

  10. 14 CFR 27.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Reserve energy absorption drop test. 27.727 Section 27.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted as...

  11. 14 CFR 29.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Reserve energy absorption drop test. 29.727 Section 29.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....727 Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted...

  12. 14 CFR 29.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Reserve energy absorption drop test. 29.727 Section 29.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION....727 Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted...

  13. 14 CFR 27.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Reserve energy absorption drop test. 27.727 Section 27.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted as...

  14. 14 CFR 27.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Reserve energy absorption drop test. 27.727 Section 27.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted as...

  15. 14 CFR 27.727 - Reserve energy absorption drop test.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Reserve energy absorption drop test. 27.727 Section 27.727 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... Reserve energy absorption drop test. The reserve energy absorption drop test must be conducted as...

  16. 14 CFR 27.725 - Limit drop test.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Limit drop test. 27.725 Section 27.725 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION AIRCRAFT AIRWORTHINESS STANDARDS: NORMAL CATEGORY ROTORCRAFT Design and Construction Landing Gear § 27.725 Limit drop test. The limit drop test must be conducted...

  17. The Illustrated Topology of Liquid Drops during Formation

    ERIC Educational Resources Information Center

    Libii, Josue Njock

    2004-01-01

    High-speed photography can show that the shape often used for a newly forming drop is wrong. Knowledge of drop behaviour is important for inkjet printers, and a close look at the formation of drops as given here can enhance critical observation, thinking and analysis.

  18. PROGRAM DROP: A computer program for prediction of evaporation from freely falling multicomponent drops

    SciTech Connect

    Gavin, P.M.

    1996-12-01

    PROGRAM DROP consists of a series of FORTRAN routine which together are used to model the evaporation of a freely falling, multicomponent drop composed of an arbitrary number of volatile species and a single nonvolatile, inert component. The physics underlying the model are clearly identified, and the model`s relationship to previous work in the literature is described. Test cases are used to illustrate the viability of the model and to highlight its potential usefulness in the accurate prediction of multicomponent droplet vaporization in a variety of applications.

  19. Innocent intentions: a correlation between forgiveness for accidental harm and neural activity.

    PubMed

    Young, Liane; Saxe, Rebecca

    2009-08-01

    Contemporary moral psychology often emphasizes the universality of moral judgments. Across age, gender, religion and ethnicity, people's judgments on classic dilemmas are sensitive to the same moral principles. In many cases, moral judgments depend not only on the outcome of the action, but on the agent's beliefs and intentions at the time of action. For example, we blame agents who attempt but fail to harm others, while generally forgiving agents who harm others accidentally and unknowingly. Nevertheless, as we report here, there are individual differences in the extent to which observers exculpate agents for accidental harms. Furthermore, we find that the extent to which innocent intentions are taken to mitigate blame for accidental harms is correlated with activation in a specific brain region during moral judgment. This brain region, the right temporo-parietal junction, has been previously implicated in reasoning about other people's thoughts, beliefs, and intentions in moral and non-moral contexts. PMID:19467357

  20. Evolution of epileptic encephalopathy in an infant with non-accidental head injury.

    PubMed

    Koul, Roshan; Poothrikovil, Rajesh; Al-Azri, Faisal; Al-Sadoon, Muna

    2013-07-01

    A 5-month-old child, previously healthy, was hospitalized with frequent episodes of tonic seizures. The seizures were controlled with antiepileptic medication. However, the parents did not continue medications after discharge from the hospital. The child was admitted several times with breakthrough seizures. Over time the seizures became refractory to treatment. Neurometabolic work up and imaging studies for uncontrolled seizures revealed non-accidental head injury (shaken baby syndrome) as the underlying cause. His first EEG was normal and changed from normal to an epileptic encephalopathy pattern during his several admissions for uncontrolled seizures. From a normal child at the first admission, the child was severely regressed at the last admission. The present paper highlights the evolution of EEG changes in a child with non-accidental head injuries. This report also highlights considering non-accidental head injury as the underlying cause in younger children presenting with unexplained epileptic encephalopathy. PMID:23887218

  1. A Native American exposure scenario.

    PubMed

    Harris, S G; Harper, B L

    1997-12-01

    EPA's Risk Assessment Guidance for Superfund (RAGS) and later documents provide guidance for estimating exposures received from suburban and agricultural activity patterns and lifestyles. However, these methods are not suitable for typical tribal communities whose members pursue, at least in part, traditional lifestyles. These lifestyles are derived from a long association with all of the resources in a particular region. We interviewed 35 members of a Columbia River Basin tribe to develop a lifestyle-based subsistence exposure scenario that represents a midrange exposure that a traditional tribal member would receive. This scenario provides a way to partially satisfy Executive Order 12,898 on environmental justice, which requires a specific evaluation of impacts from federal actions to peoples with subsistence diets. Because a subsistence diet is only a portion of what is important to a traditional lifestyle, we also used information obtained from the interviews to identify parameters for evaluating impacts to environmental and sociocultural quality of life. PMID:9463932

  2. Advanced scenarios for ITER operation

    NASA Astrophysics Data System (ADS)

    Sips, A. C. C.; Steady State Operationthe Transport Physics topical Groups of International Tokamak Physics Activity

    2005-05-01

    In thermonuclear fusion research using magnetic confinement, the tokamak is the leading candidate for achieving the conditions required for a reactor. An international experiment, ITER, is proposed as the next essential and critical step on the path to demonstrating the scientific and technological feasibility of fusion energy. ITER is to produce and study plasmas dominated by self-heating. This would give unique opportunities to explore, in reactor relevant conditions, the physics of ?-particle heating, plasma turbulence and turbulent transport, stability limits to the plasma pressure and exhaust of power and particles. Important new results obtained in experiments, theory and modelling, enable an improved understanding of the physical processes occurring in tokamak plasmas and give enhanced confidence that ITER will achieve its goals. In particular, progress has been made in research to raise the performance of tokamaks, aimed to extend the discharge pulse length towards steady-state operation (advanced scenarios). Standard tokamak discharges have a current density increasing monotonically towards the centre of the plasma. Advanced scenarios, on the other hand, use a modified current density profile. Different advanced scenarios range from (i) plasmas that sustain a central region with a flat current density profile (zero magnetic shear), capable of operating stationary at high plasma pressure, to (ii) discharges with an off-axis maximum of the current density profile (reversed magnetic shear in the core), able to form internal transport barriers, to increase the confinement of the plasma. The physics of advanced tokamak discharges is described, together with an overview of recent results from different tokamak experiments. International collaboration between experiments aims to provide a better understanding, control and optimization of these plasmas. The ability to explore advanced scenarios in ITER is very desirable, in order to verify the results obtained in experiments today and to demonstrate the potential to significantly increase the economic attractiveness of the tokamak.

  3. Electrically induced drop detachment and ejection

    NASA Astrophysics Data System (ADS)

    Cavalli, Andrea; Preston, Daniel J.; Tio, Evelyn; Martin, David W.; Miljkovic, Nenad; Wang, Evelyn N.; Blanchette, Francois; Bush, John W. M.

    2016-02-01

    A deformed droplet may leap from a solid substrate, impelled to detach through the conversion of surface energy into kinetic energy that arises as it relaxes to a sphere. Electrowetting provides a means of preparing a droplet on a substrate for lift-off. When a voltage is applied between a water droplet and a dielectric-coated electrode, the wettability of the substrate increases in a controlled way, leading to the spreading of the droplet. Once the voltage is released, the droplet recoils, due to a sudden excess in surface energy, and droplet detachment may follow. The process of drop detachment and lift-off, prevalent in both biology and micro-engineering, has to date been considered primarily in terms of qualitative scaling arguments for idealized superhydrophobic substrates. We here consider the eletrically-induced ejection of droplets from substrates of finite wettability and analyze the process quantitatively. We compare experiments to numerical simulations and analyze how the energy conversion efficiency is affected by the applied voltage and the intrinsic contact angle of the droplet on the substrate. Our results indicate that the finite wettability of the substrate significantly affects the detachment dynamics, and so provide new rationale for the previously reported large critical radius for drop ejection from micro-textured substrates.

  4. Photoinduced Capillary Motion of Drops and Bubbles

    NASA Astrophysics Data System (ADS)

    Bezuglyi, B. A.; Ivanova, N. A.

    2002-11-01

    Bubbles and drops are inhering in many liquid processes on Earth (microfluidics, MEMS technology, flows through porous media etc.) and in space laboratory under microgram conditions (preparation composite materials, degassing of liquefied matter, recycling of waste material). They could have affected these processes significantly. Therefore the study of behavior these capillary objects is necessary in order to develop the efficient methods of manipulation of them in situ. The best solution of such problem is the use of surface forces, which are aroused when the surface tension locally is departed from its equilibrium value as a result of thermal, concentration or electrical perturbations at interface. Among the known methods of control of surface tension the most promising is the thermal one. However, the generation of motion of capillary objects by the thermal gradients imposed in liquid bulk (or along solid substrate) by conduction is a passive method, which requires large amount of energy. In this paper the new method of generation of motion of bubbles and drops in microchannels or Hele-Show cells are reported. This method based on photoinduced solutocapillary convection discovered by Bezuglyi.

  5. Electrohydrodynamically Driven Chaotic Advection in Drops

    NASA Astrophysics Data System (ADS)

    Ward, Thomas; Homsy, G. M.

    2002-11-01

    When a liquid drop of given dielectric constant, resistivity and viscosity is translating in a liquid of different dielectric constant, resistivity and viscosity under Stokes flow conditions in the presence of an electric field, the resulting internal circulation is a superposition of the Hadamard-Rybcynski circulation and the circulation first described theoretically by G. I. Taylor. For sufficiently strong electric field strengths, the quadrapole structure of the Taylor circulation can cause an internal stagnation disk to occur. Our interest is in the situation where a modulation of the electric field causes the stagnation disk to modulate its position, potentially leading to chaotic flows within the drop. The dimensionless electric field strength is characterized by W = 4V(1+lambda)/U where V is the maximum interfacial velocity of the Taylor circulation, U the translational velocity, and lambda the viscosity ratio. The streamfunction for the flow is: 1) psi = (r4-r2) sin2)(theta + W(t) (r3 - r5) sin2 (theta) cos(theta) 2) W(t) = W1 + W2 cos ((epsilon)t) where epsilon is the dimensionless frequency, and W1, W2 are the amplitudes of the DC and AC components, respectively. We have found it useful to replace these parameters by a secondary set, epsilon, Wmax and delta = (1 / W1 - 1 / W2) - (1 / W1 + 1 / W2). As shown in Figure 1a, delta is the dimensionless distance the stagnation disk moves over one period of modulation. The advection equations corresponding to the flow were integrated by standard techniques, and it was found that the trajectories were chaotic over a wide range of parameters. Experiments were conducted to test the predictions of rapid mixing on convective time scales. Drops of silicon oil were suspended in a small 60 mm x 120 mm x 120 mm test cell filled with castor oil, and subject to time-modulated axial electric fields with a wave form corresponding to eq(2). The drops were typically 5 mm in diameter and settled with typical speeds of O(10-1 mm/s). Once formed, the drops were innoculated with small scattering particles and illuminated in an,equatorial plane by an Argon-ion laser. Fields of O(10-1 kV/mm) and frequencies of O(10-2 Hz) resulted in typical values of Wmax = 20, epsilon = 8, delta = 0.4. The resulting advection of the particles was imaged by a CCD camera, which collected images over a number of modulation periods. In order to make comparisons between these images and the corresponding theory, the trajectories of a large number of particles (typically O( 104)) were simulated, with initial positions approximately the same as in the experiments.

  6. Vertical vibration and shape oscillation of acoustically levitated water drops

    SciTech Connect

    Geng, D. L.; Xie, W. J.; Yan, N.; Wei, B.

    2014-09-08

    We present the vertical harmonic vibration of levitated water drops within ultrasound field. The restoring force to maintain such a vibration mode is provided by the resultant force of acoustic radiation force and drop gravity. Experiments reveal that the vibration frequency increases with the aspect ratio for drops with the same volume, which agrees with the theoretical prediction for those cases of nearly equiaxed drops. During the vertical vibration, the floating drops undergo the second order shape oscillation. The shape oscillation frequency is determined to be twice the vibration frequency.

  7. Electrohydrodynamic Interaction of a Pair of Spherical Drops

    NASA Technical Reports Server (NTRS)

    Erker, J. A.; Baygents, J. C.

    1996-01-01

    The axisymmetric electrohydrodynamic interaction between two spherical emulsion drops has been examined, using the leaky dielectric model to represent the constitutive behavior of the liquid phases. The results follow from the general solutions in bispherical coordinates to the Laplace equation for the electric potential and the Stokes equations for the velocity field. For drops of similar composition, the electrical interactions induced between the drops by the imposition of the electric field are always attractive, meaning they favor coalescence of the drop pair. The hydrodynamic interactions, however, are not always favorable and, indeed, are shown in certain circumstances to drive the drops apart.

  8. A case against the term consider the IR drop

    SciTech Connect

    Riordan, M.A. )

    1990-04-01

    The term IR drop is a part of everyday vocabulary of cathodic protection personnel. The term consider the IR drop has been a source of controversy concerning the inclusion or exclusion of the IR drop component of pipe to soil potential measurements in the determination of effective cathodic protection. Throughout the controversy, the concept of IR drop has been assumed to be valid and this has been the assumption during past years. However, the case presented in this paper indicates that a technically valid Ohmic IR drop can exist only in the metallic portion of the cathodic protection system.

  9. Surfactant-laden drops rising in a stratified ambient

    NASA Astrophysics Data System (ADS)

    Blanchette, Francois; Martin, David

    2015-11-01

    We present results of a numerical study of the dynamics of rising drops in the presence of both surfactants and stratification. Our simulations model oil drops rising in the oceans, where naturally occurring or man-made surfactants are present. We study surfactant covered drops in uniform and density-stratified ambients, as well as clean drops entering a dissolved surfactant layer. We quantify the effects of entrainment for various Reynolds and Marangoni numbers. We also report a brief acceleration followed by a significant deceleration as a clean drop enters a surfactant layer, and describe how the adsorption rate affects those dynamics.

  10. A tunnel shape defect on maxillary bone after accidental injection of formocresol instead of anesthetic solution.

    PubMed

    Ege, Bilal; Demirkol, Mehmet; Mustafa, Rawand; Aras, Mutan Hamdi

    2014-09-01

    Accidental injection or leakages of various chemical disinfectants used during root canal preparation into adjacent tissues have been shown to have deleterious effects on surrounding tissue. Formocresol (FC) is an effective intracanal disinfectant used in endodontic procedures. However, it is known to have harmful effects into adjacent tissues. The aim of this article is to present an unusual case in which a 28-year-old male patient developed gingival and bone necrosis after the accidental injection of FC instead of local anesthetic solution for tooth extraction and to review cases in the literature where complications have occurred due to the use of FC. PMID:25148635

  11. A case of delayed respiratory depression caused by accidental subcutaneous opioid infusion.

    PubMed

    Okada, Takuya; Egi, Moritoki; Sato, Hitoaki; Nomura, Yuki; Okada, Masako; Izuta, Shinichiro; Mizobuchi, Satoshi

    2016-06-01

    We report a case of delayed respiratory depression due to accidental subcutaneous opioid infusion. A healthy 33-year-old woman underwent orthopedic surgery under general anesthesia. Before the end of the operation, it was noticed that a part of the opioid infusion had been administered subcutaneously. About 15 min after tracheal extubation, the patient developed respiratory depression and loss of consciousness. The patient recovered with the use of jaw lift together with bag-valve-mask ventilation. We believe that accidental subcutaneous opioid accumulation may have caused the respiratory depression. PMID:26762999

  12. Accidental ingestion of plastic from takeaway containers--food for thought.

    PubMed

    Guirgis, Marianne; Nguyen, Robert; Pokorny, Christopher

    2011-03-01

    Foreign body oesophageal obstruction is a medical emergency. It may be accidental, particularly in children, or deliberate, for example with suicide attempts. We present two cases illustrating accidental oesophageal foreign body impaction occurring after consumption of food that had been heated in a plastic container in a microwave oven, then cut and eaten directly from the softened container. To date, we are not aware of any similar reports. In view of potential complications, care needs to be taken when food is eaten directly from plastic takeaway containers. PMID:21381997

  13. Designing Asteroid Impact Scenario Trajectories

    NASA Astrophysics Data System (ADS)

    Chodas, Paul

    2016-05-01

    In order to study some of the technical and geopolitical issues of dealing with an asteroid on impact trajectory, a number of hypothetical impact scenarios have been presented over the last ten years or so. These have been used, for example, at several of the Planetary Defense Conferences (PDCs), as well as in tabletop exercises with the Federal Emergency Management Agency (FEMA), along with other government agencies. The exercise at the 2015 PDC involved most of the attendees, consisted of seven distinct steps (“injects”), and with all the presentations and discussions, took up nearly 10 hours of conference time. The trajectory for the PDC15 scenario was entirely realistic, and was posted ahead of the meeting. It was made available in the NEO Program’s Horizons ephemeris service so that users could , for example, design their own deflection missions. The simulated asteroid and trajectory had to meet numerous very exacting requirements: becoming observable on the very first day of the conference, yet remaining very difficult to observe for the following 7 years, and far enough away from Earth that it was out of reach of radar until just before impact. It had to be undetectable in the past, and yet provide multiple perihelion opportunities for deflection in the future. It had to impact in a very specific region of the Earth, a specific number of years after discovery. When observations of the asteroid are simulated to generate an uncertainty region, that entire region must impact the Earth along an axis that cuts across specific regions of the Earth, the “risk corridor”. This is important because asteroid deflections generally move an asteroid impact point along this corridor. One scenario had a requirement that the asteroid pass through a keyhole several years before impact. The PDC15 scenario had an additional constraint that multiple simulated kinetic impactor missions altered the trajectory at a deflection point midway between discovery and impact. This talk will describe a few recent impact scenarios and outline techniques for finding trajectories that satisfy the complex constraints.

  14. Scenario Planning for Coastal Adaptation

    NASA Astrophysics Data System (ADS)

    Parris, A.; Obeysekera, J.; Knuuti, K.; Moss, R. H.; Horton, R. M.; Weiss, J. L.

    2012-12-01

    Sea level rise (SLR) is a persistent environmental change observed globally for more than a century, and its expected continuation poses significant challenges to the United States (US). We summarize a process associated with the United States National Climate Assessment for identifying four scenarios of global mean sea level rise (SLR). The main finding is that global mean sea level is expected to rise no less than 0.2 meters and no more than 2.0 meters by the end of the century. Recent publications suggest that a 4 C world would result in global mean SLR towards the upper end of that range. Aside from this process, there is currently no coordinated, interagency effort in the US to identify agreed upon global mean sea level rise projections for the purpose of coastal planning, policy, and management. This is an important gap because identifying global mean SLR estimates is a critical step in assessing coastal impacts and vulnerabilities. At present, coastal managers are left to identify global SLR estimates through their own interpretation of the scientific literature or the advice of experts on an ad-hoc basis. Yet, relative SLR at over one hundred tide gages (~80%) along the US coast reflect the global trend (1.7 - 3.2 mm/yr). No widely accepted method is currently available for producing probabilistic projections of SLR at actionable scales (i.e., regional to local). The desire to have a most probable or likely outcome can lead to paralysis or inaction for coastal decision-making. Given the range of uncertainty in future global SLR, scenario planning offers an opportunity to overcome decision-making paralysis and initiate actions now that may reduce future impacts and vulnerabilities. Scenarios do not predict future changes, but describe future potential conditions in a manner that supports decision-making under uncertainty. Using multiple scenarios, none more likely than the other, encourages experts and decision makers to rehearse multiple, plausible futures and to develop multiple response options. Coastal management actions can take anywhere from a few years for alterations to an existing levee to a decade or longer for large-scale, multi-use projects. Given the observed accelerated rate of global SLR in recent decades, it is now critical for the scientific community to help decision makers use scenario planning approaches for coastal adaptation in order to avoid future impacts of sea level rise and its effect on the frequency and magnitude of coastal flooding.

  15. Transport and Storage Cask Safety Assessment - Drop Tests and Numerical Calculations -

    SciTech Connect

    Voelzke, H.; Wille, F.; Wieser, G.; Quercetti, Th.

    2006-07-01

    BAM (the German Federal Institute for Materials Research and Testing) has been performing cask design testing for more than 30 years with a large number of prototype casks of original dimensions and of 1:2 or 1:3 scales. In 2004 a brand new drop test facility was built at the new BAM test facility at Horstwalde about 80 km to the south of Berlin. In September 2004 first demonstration tests with 2 different cask designs were performed in connection with the PATRAM 2004 conference held in Berlin. The dropped prototype casks had gross masses of 141 and 181 metric tons. Since that time BAM has been performing a lot of more drop tests with new cask designs developed by different international cask manufacturers for getting German Type B(U) transport licenses. Current safety assessments especially for mechanical accident scenarios require a combination of experimental and analytical/numerical proofs commonly, because both methods offer specific options and advantages with respect to more and more detailed structural analyses. That again is a consequence of the permanent cask design optimisation for commercial reasons leading to higher stress levels in general. For that reason BAM also improves its numerical analyses capacities including the operation of different software codes. A general BAM guideline describing basic requirements for numerical safety assessment reports gives a good orientation for both applicants and inspectors. But different details of any cask design and safety assessment have to be taken into account and lead to specific questions, investigations and experiences. This paper gives an overview about the new BAM drop test facility and the ongoing drop testing there and it presents current experiences and results of numerical cask analyses and the specific methods developed and used by BAM. In this context special attention is turned to the correlation between experimental and numerical results and an outlook to future developments is given. (authors)

  16. Thermocapillary Migration and Interactions of Bubbles and Drops

    NASA Technical Reports Server (NTRS)

    Subramaniam, R. Shankar; Balasubramaniam, R.; Wozniak, G.; Hadland, P. H.

    1999-01-01

    Experiments were performed aboard the LMS mission of the Space Shuttle in summer 1996 in the BDPU on isolated air bubbles and Fluorinert FC-75 drops as well as on interacting bubbles/drops migrating in a temperature gradient in a Dow-Corning DC-200 series silicone oil of nominal viscosity 10 centistokes. The data, recorded in the form of videotape images as well as cine images in selected runs, have been analyzed. The behavior of the isolated objects is consistent with earlier observations made aboard the IML-2 mission while the range of Reynolds and Marangoni numbers has been extended substantially over that in the IML-2 experiments. Large bubbles were found to be slightly deformed to an oblate shape while no deformation could be detected in the case of similarly large drops. Results on interacting drops and bubbles display interesting and unanticipated features. In some experiments, drops are found to follow a three-dimensional trajectory. In others, trailing drops and bubbles are found to move off the axis of the cell when migrating behind a leading drop or bubble which moves along the axis. In this type of run, if the trailing drop is sufficiently large, it is found to pass the leading drop. Finally, behavior similar to that observed in IML-2, namely that a small leading drop slows the movement of a larger trailing drop moving along the cell axis, was observed as well.

  17. An experimental study of dynamics of drop formation

    SciTech Connect

    Zhang, X.; Basaran, O.A.

    1995-06-01

    A liquid being ejected from a nozzle emanates from it as discrete, uniformly sized drops when the flow rate is sufficiently low. In this paper, an experimental study is presented of the dynamics of a viscous liquid drop that is being formed directly at the tip of a vertical tube into ambient air. The evolution in time of the drop shape and volume is monitored with a time resolution of 1/12 to 1 ms. Following the detachment of the previous drop, the profile of the new growing drop at first changes from spherical to pear-shaped. As time advances, the throat of the pear-shaped drop takes on the appearance of a liquid thread that connects the bottom portion of the drop that is about to detach to the rest of the liquid that is pendant from the tube. The focus here is on probing the effects of physical and geometric parameters on the universal features of drop formation, paying special attention to the development, extension, and breakup of the liquid thread and the satellite drops that are formed subsequent to its breakup. The role of surfactants in modifying the dynamics of drop formation is also studied. The effects of finite inertial, capillary, viscous, and gravitational forces are all accounted for to classify drastically different formation dynamics and to elucidate the fate of satellite drops following thread rupture.

  18. Drop shaping and fragmentation by laser-pulse impact

    NASA Astrophysics Data System (ADS)

    Klein, Alexander L.; Bouwhuis, Wilco; Visser, Claas Willem; Lhuissier, Henri; Snoeijer, Jacco H.; Villermaux, Emmanuel; Lohse, Detlef; Gelderblom, Hanneke

    2015-11-01

    We show how the deposition of laser energy in a superficial layer of an unconfined liquid drop can lead to propulsion, strong deformation and eventually fragmentation of the drop. Combining high-speed with stroboscopic imaging, we reveal that the laser-induced vaporization at the drop surface is the driving mechanism for the hydrodynamic response of the drop. We provide scaling arguments for the linear relations between the absorbed laser energy and both the propulsion speed and the lateral expansion of the drop prior to its fragmentation. The resulting drop shape is well reproduced by Boundary Integral simulations. Last, we show by high speed imaging in a front and side-view configuration how instabilities develop on the deforming liquid sheet, which eventually results in the drop breaking-up in smaller fragments. We characterize this fragmentation process and its dependence on the laser pulse properties.

  19. Destabilising Pickering emulsions by drop flocculation and adhesion.

    PubMed

    Whitby, Catherine P; Khairul Anwar, Hunainah; Hughes, James

    2016-03-01

    We have investigated how emulsions of water drops coated by organoclay particles destabilise in organic solvents. The drops destabilise and the emulsions undergo a fluid-solid transition if the particles are poorly wetted by the solvent. We show that the drops adhere together and form three-dimensional networks as the fraction of the poor-quality solvent in the mixture increases. Microscopic observations revealed that the drops coalesce into buckled, non-spherical shapes in mixtures rich in poor-quality solvent. A key finding is that destabilisation is favoured under conditions where the energy of adhesion between the particle layers coating drops is comparable to the energy required to detach the particles from the drops. Rupture of the interfacial layer produces particle flocs and uncoated, unstable water drops that settle out of the emulsion. PMID:26674231

  20. Metal particle compaction during drop-substrate impact for inkjet printing and drop-casting processes

    NASA Astrophysics Data System (ADS)

    Clancy, I.; Amarandei, G.; Nash, C.; Glowacki, B. A.

    2016-02-01

    Direct coating methods using metal particles from aqueous solutions or solvent-based inks become central in the roll-to-roll fabrication processes as these methods can lead to continuous or pre-defined conductive layers on a large variety of substrates. For good electrical conductivity, the metal particles have to be brought into contact, and traditionally, additional sintering treatments are required. Such treatments can degrade the sensitive substrates as paper or polymer films. In this study, the possibility of obtaining conductive layers at room temperature is investigated for direct coating methods with an emphasis on drop-casting and inkjet printing. Thus, it is shown that electrical conductive layers can be achieved if the metal particles can compact during the drop-substrate impact interaction. It is theoretically shown that the compaction process is directly related to the particle and ink drop size, the initial fractional particle loading of the ink, solvent viscosity, and drop velocity. The theoretical predictions on compaction are experimentally validated, and the particle compaction's influence on changes in the electrical conductivity of the resulting layers is demonstrated.